1.2: Pseudoscience
A pseudoscience is a belief or process which masquerades as science in an attempt to claim a legitimacy which it would not otherwise be able to achieve on its own terms; it is often known as fringe- or alternative science. The most important of its defects is usually the lack of the carefully controlled and thoughtfully interpreted experiments which provide the foundation of the natural sciences and which contribute to their advancement.
Of course, the pursuit of scientific knowledge usually involves elements of intuition and guesswork; experiments do not always test a theory adequately, and experimental results can be incorrectly interpreted or even wrong. In legitimate science, however, these problems tend to be self-correcting, if not by the original researchers themselves, then through the critical scrutiny of the greater scientific community. Critical thinking is an essential element of science.
Other Types of Defective Science
There have been several well-documented instances in which the correction process referred to above was delayed until after the initial incorrect interpretation became widely publicized, resulting in what has been called pathological science . The best known of these incidents are the "discoveries" of N-rays, of polywaters, and of cold fusion. All of these could have been averted if the researchers had not been so enthused with their results that they publicized them before they had received proper review by others. Human nature being what it is, there is always some danger of this happening; to discourage it, most of the prestigious scientific journals will refuse to accept reports of noteworthy work that has already been made public.
Another term, junk science , is often used to describe scientific theories or data which, while perhaps legitimate in themselves, are believed to be mistakenly used to support an opposing position. There is usually an element of political or ideological bias in the use of the term. Thus the arguments in favor of limiting the use of fossil fuels in order to reduce global warming are often characterized as junk science by those who do not wish to see such restrictions imposed, and who claim that other factors may well be the cause of global warming. A wide variety of commercial advertising (ranging from hype to outright fraud) would also fall into this category; at its most egregious it might better be described as deceptive science .
"99 44 100 % Pure: It Floats"
This description of Ivory Soap is a classic example of junk science from the 19th century. Not only is the term "pure" meaningless when applied to an undefined mixture such as bath soap, but the implication that its ability to float is evidence of this purity is deceptive. The low density is achieved by beating air bubbles into it, actually reducing the "purity" of the product and in a sense cheating the consumer.
Hoax science is another category that describes deliberately contrived sensationalist writings that have received wide publicity (and earned substantial royalties for their authors.) Immanual Velikovsky's Worlds in Collision (1950) is now probably the best known of these, followed by Erich von Däniken's Chariots of the Gods? (1968). Perhaps the most recent contender in this field is David Talbott, who with Wallace Thornhill wrote The Electric Universe and Thunderbolts of the Gods .
Fraudulent science and Scientific Misconduct refer to work that is intentionally fabricated or misrepresented for personal (recognition or career-advancement) or commercial (marketing or regulatory) reasons. Suppression of science for political reasons often occurred during the second Bush administration. The tobacco and pharmaceutical industries have been notoriously implicated in the latter category. The tobacco industry even published a phoney "scientific" journal containing articles written by hack authors that disputed warnings about smoking-induced cancer.
Charges of minor fudging go back to the days of Ptolemy, Gailileo, and Isaac Newton, but revelations of more contemporary frauds and their contamination of the scientific literature makes these far more problematic. Since about 1980, scientists at several major U.S. universities have been compelled to withdraw articles from prestigious journals. One of the most widely-publicized cases was that of the eminent Korean researcher who reported bogus stem cell results. Some rather troubling recent cases involve at least seventy articles describing bogus chemical structures reported by a group of scientists in China, and about an equal number of papers that had been forged or falsified by one or more scientists at a university in India.
Finally, there is just plain bad science , which would logically encompass all of the evils being discussed here, but is commonly used to describe well-intentioned but incorrect, obsolete, incomplete, or over-simplified expositions of scientific ideas. An example would be the statement that electrons revolve in orbits around the atomic nucleus, a picture that was discredited in the 1920's, but is so much more vivid and easily grasped than the one that supplanted it that it shows no sign of dying out.
Note: "It's only a theory"
In ordinary conversation, the word "theory" connotes an opinion, a conjecture, or a supposition. But in science, the term has a much more limited meaning. A scientific theory is an attempt to explain some aspect of the natural world in terms of empirical evidence and observation. It commonly draws upon established principles and knowledge with the aim of extending them in a logical and consistent way that enables one to make useful predictions. All scientific theories are tentative and subject to being tested and modified. As theories become more mature, they grow into more organized bodies of knowledge that enable us to understand and predict a wider range of phenomena. Examples of such theories are quantum theory, Einstein's theories of relativity, and evolution.
Scientific theories fall into two categories:
- Theories that have been shown to be incorrect, usually because they are not consistent with new observations;
- All other theories
Hence, theories cannot be proven to be correct; there is always the possibility that further observations will disprove the theory. Furthremore, a theory that cannot be refuted or falsified is not a scientific theory.
For example, the theories that underlie astrology (the doctrine that the positions of the stars can influence one's life) are not falsifiable because they, and the predictions that follow from them, are so vaguely stated that the failure of these predictions can always be "explained away" by assuming that various other influences were not taken into account. It is similarly impossible to falsify so-called "creation science" or "intelligent design" because one can simply evoke the "then a miracle occurs" at any desired stage.
Recognizing Pseudoscience?
There is no single test that unambiguously distinguishes between science and pseudoscience, but as the two diverge more and more from one another, certain differences become apparent, and these tend to be remarkably consistent across all fields of interest. In examining the following table, it might be helpful to consider examples of astronomy vs. astrology, or of chemistry vs. alchemy, which at one time were single fields that gradually diverged into sciences and pseudosciences.
Many scientists' ordinary response to pseudoscientific claims is simply to laugh at them. But mythology has always been an important part of human culture, often by giving people the illusion of having some direct control over their lives. This can lead to their becoming advocates for various kinds of health quackery, to commercial scams, and to cult-like organizations such as scientology. Worst of all, they can pressure political and educational circles to adopt their ideologies.
Does the "Establishment" Actively Suppress new Ideas?
Anyone who has been around for long enough has encountered statements like these:
- An inventor's design for a device that uses water as a fuel has been bought up and suppressed by the oil companies.
- "Alternative health" techniques (homeopathy, chiropractic, chelation therapy— you name it!) are actively suppressed by the medical profession or the pharmaceutical industry in a desperate attempt to serve their selfish interests.
- Reports of unidentified flying objects (UFO's) are suppressed by the U.S. Government in an attempt to prevent panic and/or to maintain control over citizens.
- Editors of scientific journals and the reviewers they call on to assess the worth of submitted papers reject out-of-hand anything that comes from persons who are not members of the scientific "establishment" or which report results not consistent with presently-accepted science.
Claims of these kinds are frequently made and widely believed, especially by those who are inclined to see conspiracies around every corner. There is little if any evidence for any of these claims. The real reason that new devices or new theories get thrown aside is that the arguments or evidence adduced to support them is inadequate or not credible. The individuals who believe themselves to be unfairly thwarted by the scientific community are very often so isolated from it that they are unable to appreciate its norms of clarity, rigor, and consistency with existing science.
A common refrain is that " they laughed at Galileo, at Thompson, and at Wegner," whose theores were eventually supported. Well, with Galileo, they did not exactly laugh; it was more a case of challenge to religious doctrine that forced him to recant his assertion that the Sun, and not the Earth, is at the center of the solar system. There have been innumerable cases in which the world was simply not ready to accept a new idea. This was especially common before the scientific method had been developed, and before the technology needed to apply it had become available.
When J.J. Thomson discovered evidence that the atom is not the ultimate fundamental particle and could be broken up into smaller units, even Thomson himself was reluctant to accept it, and he became a laughingstock for several years until more definitive evidence became available.
Alfred Wegener's theory of continental drift was bitterly attacked when it was first published in 1915, and it did not become generally accepted until about 50 years later. Others had made similar proposals based on the way the continents of Africa and South America could be fitted together, but Wegener was the first to make a careful study of fossil and geological similarities between the two continents. Nevertheless, the idea that continents could float around was too hard to accept at a time when nothing was known about the interior structure of the Earth, and the evidence he presented was rejected as inadequate.
On the other hand, the even-more-revolutionary concepts of special- and general relativity, and of quantum theory (which developed in several stages), achieved rapid acceptance when they were first presented, as did Louis Pasteur's germ theory of disease. In all of these cases the new theories provided credible explanations for what was previously unexplainable, and the tools for confirming them existed at the time, or in the case of general relativity, would soon become available.


12.3: Rigid-Body General Planar Motion
In general planar motion , bodies are both rotating and translating at the same time. As a result, we will need to relate the forces to the acceleration of the center of mass of the body as well as relating the moments to the angular accelerations.
To analyze a body undergoing general planar motion, we will start by drawing a free body diagram of the body in motion. Be sure to identify the center of mass, as well as identifying all known and unknown forces, and known and unknown moments acting on the body. It is also sometimes helpful to label any key dimensions as well as using dashed lines to identify any known accelerations or angular accelerations.
Next, we move on to identifying the equations of motion. At its core, this means going back to Newton's Second Law. Since this is a rigid body system, we include both the translational and rotational versions.
\[ \sum \vec{F} = m * \vec{a} \]
\[ \sum \vec{M} = I * \vec{\alpha} \]
As we did with the previous translational systems, we will break the force equation into components, turning the one vector equation into two scalar equations. Additionally, it's important to always use the center of mass for the accelerations in our force equations and take the moments and moment of inertia about the center of mass for our moment equation.
\[ \sum F_x = m * a_x \]
\[ \sum F_y = m * a_y \]
\[ \sum M_{COM} = I * \alpha \]
Plugging the known forces, moments, and accelerations into the above equations, we can solve for up to three unknowns. If more than three unknowns exist in the equations, we will sometimes have to go back to kinematics to relate quantities such as acceleration and angular acceleration.
Example \(\PageIndex{1}\)
A cylinder with a radius of 0.15 m and a mass of 10 kg is placed on a ramp at a 20-degree angle. If the cylinder is released from rest and rolls without slipping, what is the initial angular acceleration of the cylinder and the time required for the cylinder to roll 5 meters?
- Solution
Example \(\PageIndex{2}\)
The cable spool shown below has a weight of 50 lbs and has a moment of inertia of 0.28 slug-ft 2 . Assume the spool rolls without slipping when we apply a 50-lb tension in the cable.
- What is the friction force between the spool and the ground?
- What is the acceleration of the center of mass of the spool?
- Solution
Example \(\PageIndex{3}\)
You are designing a Frisbee launcher to launch a 40-cm-diameter, 0.6 kg Frisbee that can be modeled as flat circular disc. If you want the Frisbee to have a linear acceleration of 20 m/s 2 and an angular acceleration of 50 rad/s 2 as shown below, what should \(F_1\) and \(F_2\) be?
- Solution
Example \(\PageIndex{4}\)
A pickup truck is carrying a 30-kg, 6-meter-long ladder at a 35-degree angle as shown below. The ladder is wedged against the tailgate at A and makes contact with the roof of the truck at B. The distance from A to B is 2 meters. At what rate of acceleration would we expect the ladder to start to rotate upwards?
- Solution


5.41: The Logarithmic Series Distribution
The logarithmic series distribution , as the name suggests, is based on the standard power series expansion of the natural logarithm function. It is also sometimes known more simply as the logarithmic distribution .
Basic Theory
Distribution Functions
The logarithmic series distribution with shape parameter \( p \in (0, 1) \) is a discrete distribution on \( \N_+ \) with probability density function \( f \) given by \[ f(n) = \frac{1}{-\ln(1 - p)} \frac{p^n}{n}, \quad n \in \N_+ \]
- \( f \) is decreasing with mode \( n = 1 \).
- When smoothed, \( f \) is concave upward.
Proof
Recall that the standard power series for \( -\ln(1 - p) \), obtained by integrating the geometric series \( \sum_{n=0}^\infty p^n = 1 \big/ (1 - p) \), is \[ -\ln(1 - p) = \sum_{n=1}^\infty \frac{p^n}{n}, \quad p \in (0, 1) \] For the properties, consider the function \( x \mapsto p^x \big/ x \) on \( [1, \infty) \). The first derivative is \[ \frac{p^x [x \ln(p) - 1]}{x^2} \] which is negative, and the second derivative is \[ \frac{p^x \left[x^2 \ln^2(p) - 2 x \ln(p) + 2\right]}{x^3} \] which is positive
Open the Special Distribution Simulator and select the logarithmic series distribution. Vary the parameter and note the shape of the probability density function. For selected values of the parameter, run the simulation 1000 times and compare the empirical density function to the probability density function.
The distribution function and the quantile function do not have simple, closed forms in terms of the standard elementary functions.
Open the special distribution calculator and select the logarithmic series distribution. Vary the parameter and note the shape of the distribution and probability density functions. For selected values of the parameters, compute the median and the first and third quartiles.
Moments
Suppose again that random variable \( N \) has the logarithmic series distribution with shape parameter \( p \in (0, 1) \). Recall that the permutation formula is \( n^{(k)} = n (n - 1) \cdots (n - k + 1) \) for \( n \in \R \) and \( k \in \N \). The factorial moments of \( N \) are \( \E\left(N^{(k)}\right) \) for \( k \in \N \).
The factorial moments of \( N \) are given by \[ \E\left(N^{(k)}\right) = \frac{(k - 1)!}{-\ln(1 - p)} \left(\frac{p}{1 - p}\right)^k, \quad k \in \N_+\]
Proof
Recall that a power series can be differentialed term by term within the open interval of convergence. Hence \begin{align} \E\left(N^{(k)}\right) & = \sum_{n=1}^\infty n^{(k)} \frac{1}{-\ln(1 - p)} \frac{p^n}{n} = \frac{p^k}{-\ln(1 - p)} \sum_{n=k}^\infty n^{(k)} \frac{p^{n-k}}{n} \\ & = \frac{p^k}{-\ln(1 - p)} \sum_{n=k}^\infty \frac{d^k}{dp^k} \frac{p^n}{n} = \frac{p^k}{-\ln(1 - p)} \frac{d^k}{dp^k} \sum_{n=1}^\infty \frac{p^n}{n} \\ = & \frac{p^k}{-\ln(1 - p)} \frac{d^k}{dp^k} [-\ln(1 - p)] = \frac{p^k}{-\ln(1 - p)} (k - 1)! (1 - p)^{-k} \end{align}
The mean and variance of \( N \) are
- \[ \E(N) = \frac{1}{-\ln(1 - p)} \frac{p}{1 - p} \]
- \[ \var(N) = \frac{1}{-\ln(1 - p)} \frac{p}{(1 - p)^2} \left[1 - \frac{p}{-\ln(1 - p)} \right] \]
Proof
These results follow easily from the factorial moments . For part (b), note first that \[ \E\left(N^2\right) = \E[N(N - 1)] + \E(N) = \frac{1}{-\ln(1 - p)} \frac{p}{(1 - p)^2} \] The result then then follows from the usual computational formula \( \var(N) = \E\left(N^2\right) - [\E(N)]^2 \).
Open the special distribution simulator and select the logarithmic series distribution. Vary the parameter and note the shape of the mean \( \pm \) standard deviation bar. For selected values of the parameter, run the simulation 1000 times and compare the empirical mean and standard deviation to the distribution mean and standard deviation.
The probability generating function \( P \) of \( N \) is given by \[ P(t) = \E\left(t^N\right) = \frac{\ln(1 - p t)}{\ln(1 - p)}, \quad \left|t\right| \lt \frac{1}{p} \]
Proof
\[ P(t) = \sum_{n=1}^\infty t^n \frac{1}{-\ln(1 - p)} \frac{p^n}{n} = \frac{1}{-\ln(1 - p)} \sum_{n=1}^\infty \frac{(p t)^n}{n} = \frac{-\ln(1 - p t)}{-\ln(1 - p)} \]The factorial moments above can also be obtained from the probability generating function, since \( P^{(k)}(1) = \E\left(N^{(k)}\right) \) for \( k \in \N_+ \).
Related Distributions
Naturally, the limits of the logarithmic series distribution with respect to the parameter \( p \) are of interest.
The logarithmic series distribution with shape parameter \( p \in (0, 1) \) converges to point mass at 1 as \( p \downarrow 0 \).
Proof
An application of L'Hospitals rule to the PGF \( P \) above shows that \( \lim_{p \downarrow 0} P(t) = t \), which is the PGF of point mass at 1.
The logarithmic series distribution is a power series distribution associated with the function \( g(p) = -\ln(1 - p) \) for \( p \in [0, 1) \).
Proof
This follows from the definition of a power series distribution, since as noted in the PDF proof , \[ \sum_{n=1}^\infty \frac{p^n}{n} = - \ln(1 - p), \quad p \in [0, 1) \]
The moment results above actually follow from general results for power series distributions. The compound Poisson distribution based on the logarithmic series distribution gives a negative binomial distribution.
Suppose that \( \bs{X} = (X_1, X_2, \ldots) \) is a sequence of independent random variables each with the logarithmic series distribution with parameter \( p \in (0, 1) \). Suppose also that \( N \) is independent of \( \bs{X} \) and has the Poisson distribution with rate parameter \( r \in (0, \infty) \). Then \( Y = \sum_{i = 1}^N X_i \) has the negative binomial distribution on \( \N \) with parameters \( 1 - p \) and \( -r \big/\ln(1 - p) \)
Proof
The PGF of \( Y \) is \( Q \circ P \), where \( P \) is the PGF of the logarithmic series distribution, and where \( Q \) is the PGF of the Poisson distribution so that \( Q(s) = e^{r(s - 1)} \) for \( s \in \R \). Thus we have \[ (Q \circ P)(t) = \exp \left(r \left[\frac{\ln(1 - p t)}{\ln(1 - p)} - 1\right]\right), \quad \left|t\right| \lt \frac{1}{p} \] With a little algebra, this can be written in the form \[ (Q \circ P)(t) = \left(\frac{1 - p}{1 - p t}\right)^{-r / \ln(1 - p)}, \quad \left|t\right| \lt \frac{1}{p} \] which is the PGF of the negative binomial distribution with parameters \( 1 - p \) and \( -r \big/ \ln(1 - p) \).


5.8: Oral Suctioning
The purpose of oral suctioning is to maintain a patent airway and improve oxygenation by removing mucous secretions and foreign material (vomit or gastric secretions) from the mouth and throat (oropharynx). Oral suction is the use of a rigid plastic suction catheter, known as a yankauer (see Figure 5.3), to remove pharyngeal secretions through the mouth (Perry et al., 2014). The suction catheter has a large hole for the thumb to cover to initiate suction, along with smaller holes along the end, which mucous enters when suction is applied. The oral suctioning catheter is not used for tracheotomies due to its large size. Oral suctioning is useful to clear secretions from the mouth in the event a patient is unable to remove secretions or foreign matter by effective coughing. Patients who benefit the most include those with CVAs, drooling, impaired cough reflex related to age or condition, or impaired swallowing (Perry et al., 2014). The procedure for oral suctioning can be found in Checklist 42.
Checklist 42: Oral SuctioningDisclaimer: Always review and follow your hospital policy regarding this specific skill. |
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Safety considerations:
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Steps |
Additional Information |
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| 1. Assess patient need for suctioning (respiratory assessment for signs of hypoxia), risk for aspiration, and inability to protect own airway or clear secretions adequately, which may lead to upper airway obstruction. |
Baseline respiratory assessment, including an O
2
saturation level, can alert the health care provider to worsening condition.
Signs and symptoms include obvious excessive secretions; weak, ineffective cough; drooling; gastric secretions or vomit in the mouth; or gurgling sounds with inspiration and expiration. Pooling of secretions may lead to obstruction of airway. Suctioning is required with alterations in oxygen levels and with increased secretions. |
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| 2. Explain to patient how the procedure will help clear out secretions and will only last a few seconds. If appropriate, encourage patient to cough. |
This allows patient time to ask questions and increase compliance with the procedure. Minimizes fear and anxiety.
Encourage the patient to cough to bring secretions from the lower airways to the upper airways. |
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| 3. Position patient in semi-Fowler’s position with head turned to the side. | This facilitates ease of suctioning. Unconscious patients should be in the lateral position. | ||
| 4. Perform hand hygiene, gather supplies, and apply non-sterile gloves. Apply mask if a body fluid splash is likely to occur. |
This prevents the transmission of microorganisms. Supplies include a suction machine or suction connection, connection tubing, non-sterile gloves, yankauer, water and a sterile basin, mask, and clean towel. Suctioning may cause splashing of body fluids. |
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| 5. Fill basin with water. | Water is used to clear connection tubing in between suctions. Fill basin with enough water to clear the connection tubing at least three times. | ||
| 6. Attach one end of connection tubing to the suction machine and the other end to the yankauer. | This prepares equipment to function effectively. | ||
| 7. Turn on suction to the required level. Test function by covering hole on the yankaeur with your thumb and suctioning up a small amount of water. | Suction levels for adults are 100-150 mmHg on wall suction and 10-15 mmHg on portable suction units. Always refer to hospital policy for suction levels. | ||
| 8. Remove patient’s oxygen mask if present. Nasal prongs may be left in place. Place towel on patient’s chest. |
Always be prepared to replace the oxygen if patient becomes short of breath or has decreased O
2
saturation levels.
The towel prevents patient from coming in contact with secretions. |
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9. Insert yankauer catheter and apply suction by covering the thumb hole. Run catheter along gum line to the pharynx in a circular motion, keeping yankauer moving.
Encourage patient to cough. |
Movement prevents the catheter from suctioning to the oral mucosa and causing trauma to the tissues.
Coughing helps move secretions from the lower airways to the upper airways. Apply suction for a maximum of 10 to 15 seconds. Allow patient to rest in between suction for 30 seconds to 1 minute. |
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| 10. If required, replace oxygen on patient and clear out suction catheter by placing yankauer in the basin of water. |
Replace oxygen to prevent or minimize hypoxia.
Clearing out the catheter prevents the connection tubing from plugging. |
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| 11. Reassess and repeat oral suctioning if required. | Compare pre- and post-suction assessments to determine if intervention was effective. | ||
| 12. Reassess respiratory status and O 2 saturation for improvements. Call for help if any abnormal signs and symptoms appear. | This identifies positive response to suctioning procedure and provides objective measure of effectiveness. | ||
| 13. Ensure patient is in a comfortable position and call bell is within reach. Provide oral hygiene if required. | This promotes patient comfort. | ||
| 14. Clean up supplies, remove gloves, and wash hands. Document procedure according to hospital policy. | Cleanup prevents the transmission of microorganisms. Documentation provides accurate details of response to suctioning and clear communication among the health care team. | ||
| Data source: Perry et al., 2014; Potter et al., 2010 |
Critical Thinking Exercises
- What is the purpose of oral suctioning? Name three types of patients at risk for airway obstruction or ineffective cough.
- What is the rationale for encouraging the patient to cough before suctioning?


5.7: What issues do lesbian, gay, bisexual, and transgender students face in the classroom?
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By Jocelyn Carter
Learning Objectives
Students should be able to:
a) Identify Homophobia in Class.
b) Identify the Importance of incorporating GLBT curriculum in the classroom.
c) Describe strategies for creating a safe classroom for GLBT Students.
Introduction
Human diversity is a normal, natural thing. We teach our kids that it is alright to be different, but we don’t tell them how different it is okay to be. Today, the most common place to study differences of the world is in the classroom. If children are to grow up prepared to live in a complex, multicultural society, more issues of diversity need to be discussed in the classroom (Banks 1993). The issue of sexual orientation has become of great importance to today’s children. Researchers and Social scientist suggest that 1 to 3 of every 10 students is either gay or lesbian, or has an immediate family member who is (Wood p. 16). This article will focus on homosexuality and homophobia, GLBT students in the classroom, social bias, and what can be done to provide a safe classroom for GLBT students.
Why is “Homophobia” present in the Schools?
Most people would agree that the topic of homophobia carries very negative undertones; I guess that is unless you are homophobic. Homophobia is the fear, dislike, and hatred of same-sex relationships or those who love and are sexually attracted to those of the same sex. It occurs in schools on personal, institutional, and societal levels (Woods p 14). Homophobia is often based on ignorance, because an individual is so closed-minded that they are not willing to educate themselves on something they know nothing about. When Eric Marcus, a homosexual man and author, addressed the question, “What do students learn about homosexuality in elementary school and high school?” his answer was simply stated. “Students learn plenty about homosexuality in school, almost all of it informally, and nearly all of it bad. The first lesson occurs when one child calls another a fag in elementary school cafeteria, and the lesson continue right on through high school, when a group of students decides to torment a theater teacher they think is gay” (Marcus, 1999 p 173)
We are taught when young that being “gay” is bad.  Everyone is afraid of what they don’t know. When you are introduced to something new, it is a natural reaction to be skeptical about it. You hesitate to try it, or you state from the beginning; I know that I am not going to like it. How do we teach students about GLBT related topics? How do we protect our GLBT students in the school?
Why is it important to include GLBT related issues into the curriculum?
Imagine this, Lindsey is sitting in her 4th grade class on the first day of school, and everyone is sharing stories about their families. When it’s Lindsey’s turn she tells the class that she has two moms because they are lesbians. The class is confused and Megan asks “What is a Lesbian?” What do you do as a teacher? DO you answer the question or ignore it and change the subject? How do you answer this without overstepping your ethical boundaries? When discussing the inclusion of GLBT it is important to understand the diversity in a classroom. There may be students in your class that are already struggling with understanding their own sexual orientation. One report indicated that lesbian, gay, and bisexual students first come to realization of their sexual orientation at age 10( D’Augelli & Hershbeger, 1993) When you put that age into perspective, that child is in the 3rd or 4th grade. People fear the unknown. They fear what they are unfamiliar with. On the issue of homophobia, Kevin Jennings, executive director of the Gay, Lesbian, and Straight Education Network states, “ If you really want a long-term solution to homophobia, you’d better start when kids are young, and start teaching very early” (Quinlan, 1999).
Note
“Many of us, particularly in the dark days before the Stonewall riots, remember going into libraries to check for references that would give some validity to the vague stirrings inside us we knew marked us out as different” – Curry
Opposition
There are different reasons why incorporating GLBT issues in the classroom may come result in negative results rather than positive. It may not be the best to bring these issues up with children that are 8 or 9, even though some may already be experiencing a feeling of attraction towards the same sex, and not understand why they feel that way. Teachers could feel great discomfort in speaking about this subject in the classroom. Many parents feel that incorporating GLBT curriculum into the classroom, may cause their child to choose a gay lifestyle. When a teacher raises gay and lesbian issues in the classroom, some students respond with intellectual curiosity, but often the consequences are less positive. Some students: become embarrassed and uncomfortable, become hostile, or even question the teacher's sexuality. A lot of times students tend to make homophobic accusations against other students in the class or against other students and staff within the school (Lipkin 1999). Negative results could come about when GLBT issues are raised in the classroom.
Creating a Safe learning environment for GLBT Students
Everyone is entitled to a safe learning environment, no matter what your sexual orientation is. I think it is important to let the GLBT students know that we care, and that they are not alone. It is the duty of a teacher to keep order and command respect for everyone in their classroom, and I am sure many people sincerely would like to create a safer environment for GLBT students. There are ten suggestions that were compiled by Youth Pride, Inc. that would help with reducing homophobia in your environment:
1. Make no assumption about sexuality.
2. Having something gay-related visible in your office or classroom.
3. Support, normalize and validate student’s feelings about their sexuality.
4. Do not advise youth to come out to parents, family and friends as they need to come out at their own safe place.
5. Guarantee confidentiality with students.
6. Challenge homophobia.
7. Combat heterosexism in your classroom.
8. Learn about and refer to community organizations
9.  Provide role models.
It is important to incorporate this suggestion into the school. GLBT students need to be protected and I think the best way to start that is by educating their classmates and peers on what it means to be GLBT. “Opening these conversations with young children gives us an opportunity to prevent prejudice, discrimination, and violence and to support the lives of all children just as they are” (Chasnoff and Cohen, 1997, p 10)
Conclusion
An estimated 6 to 11 percent of school children have gay or lesbian parents, and another 5 to 9 percent will at some point realize that they are homosexual (Chasnoff and Cohen, 1997). Even with these statistics, schools are still hesitant to include gay or lesbian curriculum into the school. The fact remains that in the present 21st century, gay and lesbians no longer represent a taboo. Students are choosing to come out while still in school, and they are expecting to be accepted.  Whether or not it is the teacher’s or school’s responsibility to educate students on GLBT issues, is still to be decided. But in the meantime it is of upmost importance that these students are treated with respect and equality.
References
Banks, J. A. (1993). The canon debate, knowledge construction, and multicultural education. Educational Researcher, 22, 4-14.
Bass, E., & Kaufman, K. (1996). Free your mind. New York: HarperPerennial.
Bullough, V. L. (1979). Homosexuality: A history. New York: New American Library.
Chasnoff, D., & Cohen, H. (Producers). (1997). It’s Elementary: Talking about gay issues in school [Film]. (Available from Women’s Educational Media, San Francisco, CA) Children’s right to a loving family. (1999). Retrieved September 3, 2008 from the World Wide Web: http://www.pflag.org/press/current/tips_tactics/tips_apr99.htm
Clay, J. W. (1990).  Young Children, 45, 31-35.
D’ Augelli, A. R., & Hershberger, S. L. (1993). Lesbian, gay, and bisexual youth in community settings: Personal challenges and mental health problems. American Journal of Community Psychology, 21, 56-63.
Lipkin, Arthur (1999). Raising Gay/Lesbian Issues in the Classroom Retrieved October 1, 2008 from the World Wide Web: www.glsen.org/cgi-bin/iowa/all/news/record/193.html


23.6: Providing Culturally and Linguistically Responsive Care
By the end of this section, you should be able to:
- Identify strategies to use when communicating through an interpreter.
- Apply principles of culturally responsive care to clients and populations from diverse cultures.
- Evaluate translated materials for accuracy and effectiveness.
Nurses use a number of strategies to provide clients with culturally and linguistically competent care. These include evaluating translated materials, using communication strategies, and developing culturally tailored interventions . This section provides an overview of the skills necessary to deliver culturally responsive care and improve the health outcomes of clients from diverse cultures.
Working with Translated Materials and Interpreters
Translation and interpretation are two different processes used to exchange information from one language to another. For both, a thorough knowledge of cultural and linguistic differences is necessary to effectively communicate meaning. Translation involves written communication, in which written text in one language is converted into written text in another language. Interpretation , on the other hand, involves oral communication, in which the words spoken in one language are rendered into another language in real time. Because of the difficulties presented by the live setting, interpretation can be more challenging than translation, such as when the speakers use the wrong words, correct themselves, or use local dialects. Furthermore, unlike the translation process, interpreters lack the ability to review the text or go back and listen again. These disadvantages can make it more difficult for interpreters to accurately convey the meaning of the message.
In any clinical setting, it is critical to use certified medical interpreters, professionals trained in the use of medical terminology, cultural awareness , and ethical conduct. The interpreter should be treated as a respected professional, and extra time should be allotted for messages to be conveyed and understood (Figure 23.4). The environment should be free of distractions, and the interpreter should be provided with a summary of the client’s background, goals, and needs for the session. The name of the interpreter should be clearly documented.
When working with a client who needs an interpreter, the nurse should speak directly to the client rather than addressing the interpreter, even if the client makes eye contact with the interpreter. The nurse should observe and monitor nonverbal communication . Sentence-by-sentence interpretation and clear, simple language without medical jargon will ensure that the nurse and interpreter convey all important information to the client. The interpreter may ask open-ended questions to establish rapport or clarify client statements; during these times, the nurse should avoid interrupting the interpreter. Finally, near the end of a visit, the nurse should use the “ teach-back ” method to confirm that the client understands the directions and recommendations.
As a student or professional nurse, you may find yourself in a situation where a certified medical interpreter is not present. In these situations, it is critical to follow organizational policy and consult with leadership to locate or access remote interpretation services. Family members or friends should never be used as interpreters under any circumstances. The reasons for this are many, including a potential lack of accuracy, violation of privacy, potential conflicts of interest, and ethical and legal concerns. Think back to Cory’s interaction with Faiza. How should he have responded when the man accompanying Faiza offered to translate for her? What if the man accompanying Faiza is not actually her husband but a trafficker who has been forcing Faiza into providing commercial sex?
Developing Culturally Tailored Materials
Nurse scientists have made significant contributions to the development and implementation of culturally tailored materials and interventions to address the specific needs of different cultural groups and to improve their engagement and outcomes. According to nurse researcher Miyong Kim , adapting materials and interventions to respond to a client’s or population’s cultural needs should consider eight domains: 1) audience, 2) language, 3) contents, 4) context, 5) concepts, 6) metaphors, 7) methods, and 8) goals (Kim et al., 2022). For example, culturally tailored materials use language, content, and ideas that reflect the values and traditions of the targeted cultural group ; align with belief systems ; and frame outcomes within the customs and traditions of the targeted group.
When a professional nurse designs a culturally tailored intervention, they first identify the cultural group on which the intervention will focus. This may be a specific ethnic or racial group, a religious group, a linguistic group, or any group that has unique customs, experiences, or perspectives. So that the intervention is appropriate, acceptable, and effective, research is needed to understand the beliefs, values, and practices related to the issue being addressed (Im & Chee, 2021). This research may involve adapting an existing intervention or creating new ones, using culturally appropriate materials such as visuals, activities, and language that are respectful of the culture. Members of the targeted cultural group are often involved to ensure that the intervention is tailored to their needs (Kim et al., 2022). Involving multiple community members in the review process can help create buy-in and awareness.
The U.S. Department of Health and Human Services has developed a strategy to create culturally tailored interventions using the mnemonic CAPABLE , in which each letter represents a consideration related to the best ways to meet a community’s needs when developing educational materials (Kelly et al., 2007):
- Colors: Do the colors used have special significance for the target population?
- Art: Are the images appropriate for and reflective of the target population?
- Paper: If the materials are printed, is the paper easy to handle and read, and is its size appropriate for the target population?
- Access: Will the materials be placed in physically accessible locations? Should the information be provided electronically?
- Buy-in: Were members of the target population involved in developing or reviewing the materials? If so, do they endorse them?
- Language: Are the words in a type size most people will be able to read? Is the content easy to comprehend, appropriate for the community being served, and written at a level most readers will understand?
- Evaluation: What changes are needed to meet the needs of the target population?
After the intervention, the nurse should survey community members for feedback or observe health behaviors and outcomes to evaluate the impact of any changes made as a result of the materials. The findings would then be used to inform any revisions or additions to the materials.
This video from the CDC (2020) discusses best practices for making materials more culturally relevant for clients.
Watch the video, and then respond to the following questions.
- Why is it necessary to develop culturally adapted materials and make them available for clients?
- What are some potential barriers or challenges nurses and other health care professionals may face when developing culturally adapted materials for clients? How can these be overcome?
- In what ways can culturally adapted materials enhance client engagement, health literacy, and adherence to treatment plans?


9.2: What Is Lifespan Development?
Learning Objectives
- Define and distinguish between the three domains of development: physical, cognitive and psychosocial
- Discuss the normative approach to development
- Understand the three major issues in development: continuity and discontinuity, one common course of development or many unique courses of development, and nature versus nurture
My heart leaps up when I behold
A rainbow in the sky:
So is it now I am a man;
So be it when I shall grow old,
Or let me die!
The Child is father of the Man;
I could wish my days to be
Bound each to each by natural piety. (Wordsworth, 1802)
In this poem, William Wordsworth writes, “the child is father of the man.” What does this seemingly incongruous statement mean, and what does it have to do with lifespan development? Wordsworth might be suggesting that the person he is as an adult depends largely on the experiences he had in childhood. Consider the following questions: To what extent is the adult you are today influenced by the child you once were? To what extent is a child fundamentally different from the adult he grows up to be?
These are the types of questions developmental psychologists try to answer, by studying how humans change and grow from conception through childhood, adolescence, adulthood, and death. They view development as a lifelong process that can be studied scientifically across three developmental domains—physical, cognitive, and psychosocial development. Physical development involves growth and changes in the body and brain, the senses, motor skills, and health and wellness. Cognitive development involves learning, attention, memory, language, thinking, reasoning, and creativity. Psychosocial development involves emotions, personality, and social relationships. We refer to these domains throughout the chapter.
CONNECT THE CONCEPTS: Research Methods in Developmental Psychology
You’ve learned about a variety of research methods used by psychologists. Developmental psychologists use many of these approaches in order to better understand how individuals change mentally and physically over time. These methods include naturalistic observations, case studies, surveys, and experiments, among others.
Naturalistic observations involve observing behavior in its natural context. A developmental psychologist might observe how children behave on a playground, at a daycare center, or in the child’s own home. While this research approach provides a glimpse into how children behave in their natural settings, researchers have very little control over the types and/or frequencies of displayed behavior.
In a case study, developmental psychologists collect a great deal of information from one individual in order to better understand physical and psychological changes over the lifespan. This particular approach is an excellent way to better understand individuals, who are exceptional in some way, but it is especially prone to researcher bias in interpretation, and it is difficult to generalize conclusions to the larger population.
In one classic example of this research method being applied to a study of lifespan development Sigmund Freud analyzed the development of a child known as “Little Hans” (Freud, 1909/1949). Freud’s findings helped inform his theories of psychosexual development in children, which you will learn about later in this chapter. Little Genie, the subject of a case study discussed in the chapter on thinking and intelligence, provides another example of how psychologists examine developmental milestones through detailed research on a single individual. In Genie’s case, her neglectful and abusive upbringing led to her being unable to speak until, at age \(13\), she was removed from that harmful environment. As she learned to use language, psychologists were able to compare how her language acquisition abilities differed when occurring in her late-stage development compared to the typical acquisition of those skills during the ages of infancy through early childhood (Fromkin, Krashen, Curtiss, Rigler, & Rigler, 1974; Curtiss, 1981).
The survey method asks individuals to self-report important information about their thoughts, experiences, and beliefs. This particular method can provide large amounts of information in relatively short amounts of time; however, validity of data collected in this way relies on honest self-reporting, and the data is relatively shallow when compared to the depth of information collected in a case study.
Experiments involve significant control over extraneous variables and manipulation of the independent variable. As such, experimental research allows developmental psychologists to make causal statements about certain variables that are important for the developmental process. Because experimental research must occur in a controlled environment, researchers must be cautious about whether behaviors observed in the laboratory translate to an individual’s natural environment.
Later in this chapter, you will learn about several experiments in which toddlers and young children observe scenes or actions so that researchers can determine at what age specific cognitive abilities develop. For example, children may observe a quantity of liquid poured from a short, fat glass into a tall, skinny glass. As the experimenters question the children about what occurred, the subjects’ answers help psychologists understand at what age a child begins to comprehend that the volume of liquid remained the same although the shapes of the containers differs.
Across these three domains—physical, cognitive, and psychosocial—the normative approach to development is also discussed. This approach asks, “What is normal development?” In the early decades of the \(20^{th}\) century, normative psychologists studied large numbers of children at various ages to determine norms (i.e., average ages) of when most children reach specific developmental milestones in each of the three domains (Gesell, 1933, 1939, 1940; Gesell & Ilg, 1946; Hall, 1904). Although children develop at slightly different rates, we can use these age-related averages as general guidelines to compare children with same-age peers to determine the approximate ages they should reach specific normative events called developmental milestones (e.g., crawling, walking, writing, dressing, naming colors, speaking in sentences, and starting puberty).
Not all normative events are universal, meaning they are not experienced by all individuals across all cultures. Biological milestones, such as puberty, tend to be universal, but social milestones, such as the age when children begin formal schooling, are not necessarily universal; instead, they affect most individuals in a particular culture (Gesell & Ilg, 1946). For example, in developed countries children begin school around 5 or 6 years old, but in developing countries, like Nigeria, children often enter school at an advanced age, if at all (Huebler, 2005; United Nations Educational, Scientific, and Cultural Organization [UNESCO], 2013).
To better understand the normative approach, imagine two new mothers, Louisa and Kimberly, who are close friends and have children around the same age. Louisa’s daughter is \(14\) months old, and Kimberly’s son is \(12\) months old. According to the normative approach, the average age a child starts to walk is \(12\) months. However, at \(14\) months Louisa’s daughter still isn’t walking. She tells Kimberly she is worried that something might be wrong with her baby. Kimberly is surprised because her son started walking when he was only \(10\) months old. Should Louisa be worried? Should she be concerned if her daughter is not walking by \(15\) months or \(18\) months?
Issues in Developmental Psychology
There are many different theoretical approaches regarding human development. As we evaluate them in this chapter, recall that developmental psychology focuses on how people change, and keep in mind that all the approaches that we present in this chapter address questions of change: Is the change smooth or uneven (continuous versus discontinuous)? Is this pattern of change the same for everyone, or are there many different patterns of change (one course of development versus many courses)? How do genetics and environment interact to influence development (nature versus nurture)?
Is Development Continuous or Discontinuous?
Continuous development views development as a cumulative process, gradually improving on existing skills (See figure \(\PageIndex{1}\)). With this type of development, there is gradual change. Consider, for example, a child’s physical growth: adding inches to her height year by year. In contrast, theorists who view development as discontinuous believe that development takes place in unique stages: It occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to conceive object permanence.
Is There One Course of Development or Many?
Is development essentially the same, or universal, for all children (i.e., there is one course of development) or does development follow a different course for each child, depending on the child’s specific genetics and environment (i.e., there are many courses of development)? Do people across the world share more similarities or more differences in their development? How much do culture and genetics influence a child’s behavior?
Stage theories hold that the sequence of development is universal. For example, in cross-cultural studies of language development, children from around the world reach language milestones in a similar sequence (Gleitman & Newport, 1995). Infants in all cultures coo before they babble. They begin babbling at about the same age and utter their first word around 12 months old. Yet we live in diverse contexts that have a unique effect on each of us. For example, researchers once believed that motor development follows one course for all children regardless of culture. However, child care practices vary by culture, and different practices have been found to accelerate or inhibit achievement of developmental milestones such as sitting, crawling, and walking (Karasik, Adolph, Tamis-LeMonda, & Bornstein, 2010).
For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around \(23-25\0 months old, in comparison to infants in Western cultures who begin to walk around \(12\) months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age \(9\), their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to \(25\) feet tall and use machetes to chop their way through the forest (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions themselves are present in all societies (See figure below).
How Do Nature and Nurture Influence Development?
Are we who we are because of nature (biology and genetics), or are we who we are because of nurture (our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our parents, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from the parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?
We are all born with specific genetic traits inherited from our parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment: Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). This chapter will show that there is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.
DIG DEEPER: The Achievement Gap - How Does Socioeconomic Status Affect Development?
The achievement gap refers to the persistent difference in grades, test scores, and graduation rates that exist among students of different ethnicities, races, and—in certain subjects—sexes (Winerman, 2011). Research suggests that these achievement gaps are strongly influenced by differences in socioeconomic factors that exist among the families of these children. While the researchers acknowledge that programs aimed at reducing such socioeconomic discrepancies would likely aid in equalizing the aptitude and performance of children from different backgrounds, they recognize that such large-scale interventions would be difficult to achieve. Therefore, it is recommended that programs aimed at fostering aptitude and achievement among disadvantaged children may be the best option for dealing with issues related to academic achievement gaps (Duncan & Magnuson, 2005).
Low-income children perform significantly more poorly than their middle- and high-income peers on a number of educational variables: They have significantly lower standardized test scores, graduation rates, and college entrance rates, and they have much higher school dropout rates. There have been attempts to correct the achievement gap through state and federal legislation, but what if the problems start before the children even enter school?
Psychologists Betty Hart and Todd Risley (2006) spent their careers looking at early language ability and progression of children in various income levels. In one longitudinal study, they found that although all the parents in the study engaged and interacted with their children, middle- and high-income parents interacted with their children differently than low-income parents. After analyzing \(1,300\) hours of parent-child interactions, the researchers found that middle- and high-income parents talk to their children significantly more, starting when the children are infants. By \(3\) years old, high-income children knew almost double the number of words known by their low-income counterparts, and they had heard an estimated total of \(30\) million more words than the low-income counterparts (Hart & Risley, 2003). And the gaps only become more pronounced. Before entering kindergarten, high-income children score \(60\%\) higher on achievement tests than their low-income peers (Lee & Burkam, 2002).
There are solutions to this problem. At the University of Chicago, experts are working with low-income families, visiting them at their homes, and encouraging them to speak more to their children on a daily and hourly basis. Other experts are designing preschools in which students from diverse economic backgrounds are placed in the same classroom. In this research, low-income children made significant gains in their language development, likely as a result of attending the specialized preschool (Schechter & Byeb, 2007). What other methods or interventions could be used to decrease the achievement gap? What types of activities could be implemented to help the children of your community or a neighboring community?
Summary
Lifespan development explores how we change and grow from conception to death. This field of psychology is studied by developmental psychologists. They view development as a lifelong process that can be studied scientifically across three developmental domains: physical, cognitive development, and psychosocial. There are several theories of development that focus on the following issues: whether development is continuous or discontinuous, whether development follows one course or many, and the relative influence of nature versus nurture on development.
Glossary
- cognitive development
- domain of lifespan development that examines learning, attention, memory, language, thinking, reasoning, and creativity
- continuous development
- view that development is a cumulative process: gradually improving on existing skills
- developmental milestone
- approximate ages at which children reach specific normative events
- discontinuous development
- view that development takes place in unique stages, which happen at specific times or ages
- nature
- genes and biology
- normative approach
- study of development using norms, or average ages, when most children reach specific developmental milestones
- nurture
- environment and culture
- physical development
- domain of lifespan development that examines growth and changes in the body and brain, the senses, motor skills, and health and wellness
- psychosocial development
- domain of lifespan development that examines emotions, personality, and social relationships
Contributors
-
Rose M. Spielman with many significant contributors. The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the creative commons license and may not be reproduced without the prior and express written consent of Rice University. For questions regarding this license, please contact<EMAIL_ADDRESS>.Textbook content produced by OpenStax College is licensed under a Creative Commons Attribution License 4.0 license. Download for free at<EMAIL_ADDRESS>.


1.1: Alfred Lothar Wegener
Moving continents
Perhaps Alfred Wegener's greatest contribution to the scientific world was his ability to weave seemingly dissimilar, unrelated facts into a theory, which was remarkably visionary for the time. Wegener was one of the first to realize that an understanding of how the Earth works required input and knowledge from all the earth sciences.
Wegener's scientific vision sharpened in 1914 as he was recuperating in a military hospital from an injury suffered as a German soldier during World War I. While bed-ridden, he had ample time to develop an idea that had intrigued him for years. Like others before him, Wegener had been struck by the remarkable fit of the coastlines of South America and Africa. But, unlike the others, to support his theory Wegener sought out many other lines of geologic and paleontologic evidence that these two continents were once joined. During his long convalescence, Wegener was able to fully develop his ideas into the Theory of Continental Drift, detailed in a book titled Die Entstehung der Kontinente und Ozeane (in German, The Origin of Continents and Oceans) published in 1915.
Alfred Lothar Wegener (1880-1930), the originator of the theory of continental drift. (Photograph courtesy of the Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.)
Wegener obtained his doctorate in planetary astronomy in 1905 but soon became interested in meteorology; during his lifetime, he participated in several meteorologic expeditions to Greenland. Tenacious by nature, Wegener spent much of his adult life vigorously defending his theory of continental drift, which was severely attacked from the start and never gained acceptance in his lifetime. Despite overwhelming criticism from most leading geologists, who regarded him as a mere meteorologist and outsider meddling in their field, Wegener did not back down but worked even harder to strengthen his theory.
A couple of years before his death, Wegener finally achieved one of his lifetime goals: an academic position. After a long but unsuccessful search for a university position in his native Germany, he accepted a professorship at the University of Graz in Austria. Wegener's frustration and long delay in gaining a university post perhaps stemmed from his broad scientific interests. As noted by Johannes Georgi, Wegener's longtime friend and colleague, "One heard time and again that he had been turned down for a certain chair because he was interested also, and perhaps to a greater degree, in matters that lay outside its terms of reference -- as if such a man would not have been worthy of any chair in the wide realm of world science."
Ironically, shortly after achieving his academic goal, Wegener died on a meteorologic expedition to Greenland. Georgi had asked Wegener to coordinate an expedition to establish a winter weather station to study the jet stream (storm track) in the upper atmosphere. Wegener reluctantly agreed. After many delays due to severe weather, Wegener and 14 others set out for the winter station in September of 1930 with 15 sledges and 4,000 pounds of supplies. The extreme cold turned back all but one of the 13 Greenlanders, but Wegener was determined to push on to the station, where he knew the supplies were desperately needed by Georgi and the other researchers. Travelling under frigid conditions, with temperatures as low as minus 54 °C, Wegener reached the station five weeks later. Wanting to return home as soon as possible, he insisted upon starting back to the base camp the very next morning. But he never made it; his body was found the next summer.
Alfred Wegener (left) and an Innuit guide on 1 November 1930 during his final meteorological expedition in Greenland. This is one of the last photographs of Wegener, who died later during the expedition (see text). (Photograph courtesy of the Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.)
Wegener was still an energetic, brilliant researcher when he died at the age of 50. A year before his untimely death, the fourth revised edition (1929) of his classic book was published; in this edition, he had already made the significant observation that shallower oceans were geologically younger. Had he not died in 1930, Wegener doubtless would have pounced upon the new Atlantic bathymetric data just acquired by the German research vessel Meteor in the late 1920s. These data showed the existence of a central valley along much of the crest of the Mid-Atlantic Ridge. Given his fertile mind, Wegener just possibly might have recognized the shallow Mid-Atlantic Ridge as a geologically young feature resulting from thermal expansion, and the central valley as a rift valley resulting from stretching of the oceanic crust. From stretched, young crust in the middle of the ocean to seafloor spreading and plate tectonics would have been short mental leaps for a big thinker like Wegener. This conjectural scenario by Dr. Peter R. Vogt (U.S. Naval Research Laboratory, Washington, D.C.), an acknowledged expert on plate tectonics, implies that "Wegener probably would have been part of the plate-tectonics revolution, if not the actual instigator, had he lived longer." In any case, many of Wegener's ideas clearly served as the catalyst and framework for the development of the theory of plate tectonics three decades later.
Contributors and Attributions
W. Jacquelyne Kious and Robert Tilling (" The Dynamic Earth " via the U.S. Geological Survey )


11.1.4B: Discrimination Against Individuals
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Discrimination is the prejudicial treatment of an individual based on his or her membership (or perceived membership) in a certain group.
Learning Objectives
- Give an example of discrimination and reverse discrimination using examples of religious, gender, or racial prejudice
Key Points
- A common type of discrimination is the exclusion or restriction of members of one group from opportunities that are available to another group.
- Racial, religious, and gender discrimination are common types of this phenomenon.
- Controversial attempts have been made to mitigate and rectify the negative effects of discrimination. These attempts in turn, however, have sometimes been called reverse discrimination.
- Reverse discrimination is a term referring to discrimination against members of a dominant or majority group, including the city or state, or in favor of members of a minority or historically disadvantaged group.
Key Terms
- reverse discrimination : Discrimination against members of a dominant or majority group, including the city or state, or in favor of members of a minority or historically disadvantaged group.
- discrimination : The prejudicial treatment of an individual based on his or her membership, or perceived membership, in a certain group or category.
Discrimination is the prejudicial treatment of an individual based on his/her membership (or perceived membership) in a certain group or category, and involves actual actions taken towards that individual. A common example of discrimination is the exclusion or restriction of members of one group from opportunities that are available to another group, such as access to public facilities like bathrooms and water fountains.
Controversial attempts have been made to redress negative effects of discrimination. One example is the implementation of racial quotas, that is, establishing numerical requirements for hiring, promoting, admitting and/or graduating members of a particular racial group. These attempts in turn, however, have sometimes been called reverse discrimination (see below).
Racial and Ethnic Discrimination
Racial discrimination results in unequal treatment between individuals on the basis of real and perceived racial differences. It may manifest on every level of social life, from minor disregard or intense hostility in interpersonal interactions to much larger instantiations in public institutions (also called structural or institutional discrimination), such as the segregatory practices prominent in the Jim Crow era of the Unites States (1870s-1960s).
Sex, Gender and Gender Identity Discrimination
Though what constitutes sex discrimination varies between countries, it essentially refers to an adverse action taken against a person based on their perceived sex, gender, and/or gender identity. Historically, sexual differences have been used to justify different social roles for men and women. Unfair discrimination usually follows the gender stereotypes held by a society.
Religious Discrimination
Religious discrimination is prejudicial treatment of a person or group differently based on their spiritual or religious beliefs (or lack thereof).
In a 1979 consultation on the issue, the United States commission on civil rights defined religious discrimination in relation to the civil rights guaranteed by the Fourteenth Amendment to the United States Constitution, which deals with due process and equal fairness of all citizens under the law. According to the commission, religious discrimination occurs when someone is denied ” the equal protection of the laws, equality of status under the law, equal treatment in the administration of justice, and equality of opportunity and access to employment, education, housing, public services and facilities, and public accommodation because of their exercise of their right to religious freedom. ”
Reverse Discrimination
Reverse discrimination is a term referring to discrimination against members of a dominant or majority group, including the city or state, or in favor of members of a minority or historically disadvantaged group. Groups may be defined in terms of race, gender, ethnicity, or other factors. This discrimination may seek to redress social inequalities where minority groups have been denied access to the same privileges of the majority group. In such cases it is intended to remove discrimination that minority groups may already face.
Reverse discrimination may also be used to highlight the discrimination inherent in affirmative action programs.
Legislation in some nations, such as the UK, assert that identical treatment may sometimes act to preserve inequality rather than eliminate it, and therefore this so-called reverse discrimination is justified.


14.8: Andromeda Galaxy
In 1917, Heber Curtis (1872-1942) was observing a nova in the Andromeda “nebula. ” Researching previous novae, including those in the Milky Way Galaxy, Curtis was convinced that Andromeda was indeed a galaxy much like the Milky Way Galaxy, and that the dust lanes seen in Andromeda were similar to those in the Milky Way Galaxy. Edwin Hubble (1889-1953) settled that question a couple of years later when his research and observations determined “nebula” like Andromeda were indeed actually galaxies.
One of the questions at the time was the location of our Solar System within the Milky Way Galaxy. Harlow Shapley (1885-1972) used globular clusters to show where we “live” in our galaxy. Shapley was also able to estimate the size of the Milky Way Galaxy. Yet not all of Shapley’s observations or hypotheses were correct; perhaps the biggest error was his continued argument that spiral ‘nebulae’ were actually galaxies outside the Milky Way Galaxy. Shapley actually referred to Hubble’s work and findings as “junk science. ”
Also visible in this image are two companion galaxies of the Andromeda Galaxy. Note the dark lanes within the broad band of stars; these are the dust lanes within the Milky Way Galaxy.
Most modern Milky Way Galaxy research has covered such questions as the type and size of the galaxy, the existence of a supermassive black hole at the Milky Way Galaxy’s center, and satellite galaxies associated with the Milky Way Galaxy.
Recall, Sagittarius A * , SGR A * , the Milky Way Galaxy’s supermassive black hole, was discovered in 1974. Its characteristics were speculative for a number of years. Continued observations of stars near Sagittarius A* indicate that the object is indeed a supermassive galactic black hole.
The Virgo Stellar Stream was discovered in 2006. This is a collection of stars which rises close to perpendicular to the plane of the spiral arms of the galaxy; most likely this structure is a dwarf galaxy.


24.10: Spectroscopy of Amines
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- Steven Farmer & Dietmar Kennepohl
- University of Illinois Springfield
Objectives
After completing this section, you should be able to
- identify the region of the infrared spectrum that shows absorptions resulting from the \(\ce{N-H}\) bonds of primary and secondary amines.
- describe a characteristic change that occurs in the infrared spectrum of an amine when a small amount of mineral acid is added to the sample.
- use 1 H NMR spectra in determining the structure of an unknown amine.
- use the “nitrogen rule” of mass spectrometry to determine whether a compound has an odd or even number of nitrogen atoms in its structure.
- predict the prominent peaks in the mass spectrum of a given amine.
- use the mass spectrum of an unknown amine in determining its structure.
Key Terms
Make certain that you can define, and use in context, the key term below.
- nitrogen rule
Study Notes
You should note the spectroscopic similarities between amines and alcohols: both have infrared absorptions in the 3300–3360 cm −1 region, and in both cases, the proton that is attached to the heteroatom gives rise to an often indistinct signal in the 1 H NMR spectrum.
1 H NMR of Amines
The hydrogens attached to an amine show up ~ 0.5-5.0 ppm. The location is dependent on the amount of hydrogen bonding and the sample's concentration. The hydrogens on carbons directly bonded to an amine typically appear ~2.3-3.0 ppm. These hydrogens are deshielded by the electron-withdrawing effects of nitrogen and appear downfield in an NMR spectra compared to alkane hydrogens.
Addition of D 2 O will normally cause all hydrogens on non-carbon atoms to exchange with deuterium, thus making these resonances "disappear." Addition of a few drops of D 2 O causing a signal to vanish can help confirm the presence of -NH.
13 C NMR of Amines
Carbons directly attached to the nitrogen appear in 10-65 ppm region of a 13 C NMR spectra. They are shifted slightly downfield compared to alkane carbons due to the electron-withdrawing effect of nitrogen again causing deshielding.
IR of Amines
The infrared spectra of several amines are shown beneath the following table. Some of the characteristic absorptions for C-H stretching and aromatic ring substitution are also marked, but not colored.
| Amine Class | Stretching Vibrations | Bending Vibrations | |
|---|---|---|---|
| Primary (1°) |
The N-H stretching absorption is less sensitive to hydrogen bonding than are O-H absorptions. In the gas phase and in dilute CCl
4
solution free N-H absorption is observed in the 3400 to 3500 cm
-1
region. Primary aliphatic amines display two well-defined peaks due to asymmetric (higher frequency) and symmetric N-H stretching, separated by 80 to 100 cm
-1
. In aromatic amines these absorptions are usually 40 to 70 cm
-1
higher in frequency. A smaller absorption near 3200 cm
-1
(shaded orange in the spectra) is considered to be the result of interaction between an overtone of the 1600 cm
-1
band with the symmetric N-H stretching band.
|
Strong in-plane NH 2 scissoring absorptions at 1550 to 1650 cm -1 , and out-of-plane wagging at 650 to 900 cm -1 (usually broad) are characteristic of 1°-amines. | |
| Secondary (2°) |
Secondary amines exhibit only one absorption near 3420 cm
-1
. Hydrogen bonding in concentrated liquids shifts these absorptions to lower frequencies by about 100 cm
-1
. Again, this absorption appears at slightly higher frequency when the nitrogen atom is bonded to an aromatic ring.
|
A weak N-H bending absorption is sometimes visible at 1500 to 1600 cm -1 . A broad wagging absorption at 650 to 900 cm -1 may be discerned in liquid film samples. | |
| Tertiary (3°) | No N-H absorptions. The C-N absorptions are found in the same range, 1200 to 1350 cm -1 (aromatic) and 1000 to 1250 cm -1 (aliphatic) as for 1°-amines. | Aside from the C-N stretch noted on the left, these compounds have spectra characteristic of their alkyl and aryl substituents. |
UV/Vis Spectra of Amines
Alky Amines absorb in the region around 200 nm which make them of little value. In arylamines, the lone pair electron on the nitrogen interacts with pi electron system of the aromatic ring shifting the ring 's absorption to longer wavelengths. An example is benzene's lambda max of 256 nm while aniline's lambda max of 280 nm.
Mass Spectra of Amines
Nitrogen Rule
The nitrogen rule states that a molecule that has no or even number of nitrogen atoms has an even nominal mass, whereas a molecule that has an odd number of nitrogen atoms has an odd nominal mass.
Example
Fragmentation Patterns
The molecular ion peak is an odd number any time there is an odd number of nitrogen atoms in a molecule.. The mass spectra of amines is dominated by alpha-cleavage which produces an alkyl radical on a resonance stabilized nitrogen containing cation. Secondary and tertiary amines have the possibility of multiple alpha-cleavages.
N-Butylamine (C 4 H 11 N) with MW = 73.13
Another example is a secondary amine shown below. Again, the molecular ion peak is an odd number. The base peak (m/z = 44) is from the C-C cleavage adjacent to the C-N bond. Other important peaks come from the cleavage of the N-H bond (m/z = 120) and cleavage at the benzylic position (m/z = 91).
N-Methylbenzylamine (C 8 H 11 N) with MW = 121.18


3.1: Algebra Tips and Tricks Part V (Exponents)
Exponents
When simplifying exponents, remember the exponentiation is just repeated multiplications. So if you have something like
\(x^3 x^7\)
This is three \(x\)s multiplied by seven \(x\)s, so that’s ten \(x\)s all multiplied together.
\(x^3 x^7 = x^{10}\)
Similarly, all these other rules don’t even have to be memorized if you just think about how repeated multiplication would work. But here they are anyway.
\[\begin{align*} A^x A^y & = A^{x + y} \\ \frac{A^x}{A^y} & = A^{x - y} \\ \left( A^x \right)^y & = A^{xy} \\ A^{-x} & = \frac{1}{A^x} \\ A^0 & = 1 \end{align*}\]
Some examples:
-
\(\frac{e^{11}}{e^5 e^4}\).
Here we have eleven \(e\)s, and we are taking away via division five of them then four of them. Hence we have two \(e\)s left over: \(\frac{e^{11}}{e^5 e^4} = \boxed{e^2}\). Note that \(e\) is a fundamental constant in mathematics, like \(\pi\), equal to \(2.718281828459045\ldots\) approximately, but we just use \(e\) for the exact value.
-
\(\frac{(A^4 B)^3}{(A B^4)^2}\).
We see \((A^4 B)^3 = A^{12} B^3\). On bottom, we have \((A B^4)^2 = A^2 B^8\). This give \(\frac{A^{12} B^3}{A^2 B^8}\). Once we get cancel two of the As and three of the Bs, we have \(\boxed{\frac{A^{10}}{B^5}}\).
-
\(\left(\frac{\sqrt{2} + \sqrt{3} + \sqrt{5} + \sqrt{7}}{\sqrt[4]{104942}} \right)^{x - x}\).
This looks ugly, but \(x - x = 0\), and anything to the zeroth power is \(1\). Hence the answer is \(\boxed{1}\).
-
\(a^{-5}a^2\).
This combines as \(a^{-5 + 2} = a^{-3}\), which we can also write as \(\boxed{\frac{1}{a^3}}\).
Fractional Exponents
One more rule before you go: . In other words, a fraction in the exponent is the same thing as taking a square root, cube root, 4th root, etc, depending on what the denominator is. Some examples:
-
.
We see this is the same thing as \(\sqrt{25}\), which is \(\boxed{5}\).
-
.
This is the same thing as \(\left( \sqrt[3]{8}\right)^2\). We see that \(\sqrt[3]{8} = 2\), and hence we do \(2^2 = 4\). So .


3.3: Putting It Together- People Analytics and Human Capital Trends
As a society and as organizations, we are inundated with data and information. However, in an organizational context, that data has no value until it can be applied to solve business problems. As one people analytics leader put it: “I am not in the curiosity business. We need to know the relevance to the business before we spend time and energy to work on a problem.” [1] People analytics expert Josh Bersin captures the essence of the practice with his observation that “We used to think the secret to productivity at work was ‘skills.’ Now, through the use of [scientific methods], we can understand that the secret is also ‘behaviors,’ ‘habits,” and ‘patterns’ that highly successful people adopt.” [2] The amount of available data and processing capacity also allows us to solve questions of greater complexity, quantifying issues so management can evaluate the significance and respond accordingly.
For example, here are some of the questions people analytics consultant Patrick Coolen has used analytics to address: [3]
- What HR factors (e.g. engagement, leadership, individual and team characteristics, competencies and skills) are impacting client satisfaction, sales, net growth and the quality of our offerings?
- What factors are driving employee engagement worldwide?
- How is diversity within teams positively influencing our business goals (financial and customer satisfaction) and to what extent?
- Can we predict successful hires based on our selection data, resulting in hires that are more likely to perform and stay with our organization?
- What leadership characteristics have a positive impact on business goals including engagement?
- How is the notion of a shared purpose between employee and our organization contributing to engagement and business performance?
People analytics is still, relatively speaking, in its infancy, with practitioners reporting case data with a mixture of wonder and excitement. Hype and adoption challenges aside, the potential is real. We’ll close this module with a case that is the modern counterpoint to the Hawthorne studies referenced in Module 2: Human Resource Strategy and Planning.
In 2012, Google launched an initiative to discover the secrets of effective teams. Channelling Aristotle’s “the whole is greater than the sum of its parts” idea, the initiative was named Project Aristotle. The project goal: answer the question “What makes a team effective at Google?”
Researchers started by reviewing the academic literature on teamwork and then began analyzing the composition of Google’s teams, including social habits, hobbies and educational backgrounds. However, regardless of how they parsed the data, the researchers were unable to find patterns or evidence that the composition of a team made a difference. As The New York Times reports, “most confounding of all, two teams might have nearly identical makeups, with overlapping memberships, but radically different levels of effectiveness.” In their attempts to understand the dynamics, the team honed in on an idea that kept coming up in their research: the concept of “group norms,” or the “unspoken and often unwritten set of informal rules that govern individual behaviors in a group.” [4] The influence of norms can be profound, since they typically override individual behavior preferences. Ultimately, the team determined that performance wasn’t a function of who was on the team per se but how the team worked together, resulting in the five key characteristics of effective teams: [5]
- Psychological Safety. Team members feel safe with one another and are willing to take risks and be vulnerable
- Dependability. Team members get things done on time
- Structure & Clarity. Team members have clear roles, plans, and goals
- Meaning. Work is important and meaningful to individual team members
- Impact. Team members believe their work creates a meaningful change
Project Aristotle taught Googlers that “no one wants to put on a ‘work face’ when they get to the office. No one wants to leave part of their personality and inner life at home.” Perhaps more importantly, the project taught them about being human. As one Googler stated: “We can’t be focused just on efficiency. We want to know that work is more than just labor.” Times senior editor Charles Duhigg notes: the ‘‘employee performance optimization’’ movement [people analytics] has given us the tools to quickly teach lessons that once took managers decades to absorb. In conclusion, Rozovsky observes: ‘‘just having data that proves to people that these things are worth paying attention to sometimes is the most important step in getting them to actually pay attention.’’
Watch Google Project Aristotle team leaders Abeer Dubey and Julia Rozobsky’s summary:
You can also download a transcript for the video “Google’s five keys to a successful team.”
For additional perspective on team effectiveness, read The New York Times article “What Google Learned From It’s Quest to Build the Perfect Team,” which also includes findings from a related study into team effectiveness and intelligence.
-
Bersin, Josh. "
People Analytics: Here With A Vengeance
." Forbes. December 16, 2017. Accessed August 06, 2019. ↵
-
Ibid. ↵
-
Coolen, Patrick. "
The 10 Golden Rules of HR Analytics (crowd Version)
." LinkedIn. September 16, 2016. Accessed August 06, 2019. ↵
-
"Group Norms." BusinessDictionary. Accessed October 28, 2019. ↵
-
Green, David. "40 People Analytics Case Studies – Part 3." LinkedIn. December 7, 2016. Accessed August 06, 2019. ↵


9.9: Introduction to Rhetorical Appeals
What you’ll learn to do: describe and apply the rhetorical appeals of logos, pathos, and ethos
When writing or analyzing arguments, we begin by examining how the argument appeals to the reader. There are three types of appeals utilized in arguments: logos or logical, pathos or emotional, and ethos or ethical appeals. Aristotle identified these rhetorical appeals as fundamental elements in the art of persuasion. In this section, you will learn how to recognize and utilize these appeals in your own speaking and writing.
Contributors and Attributions
CC licensed content, Original
- Why It Matters: Rhetorical Appeals. Provided by : University of Mississippi. License : CC BY: Attribution
- Modification, adaptation, and original content. Provided by : Lumen Learning. License : CC BY: Attribution
CC licensed content, Shared previously
- Ostia, Baths of the Seven Sages (II). Authored by : Institute for the Study of the Ancient World. Located at : https://www.flickr.com/photos/isawnyu/4687819515/ . License : CC BY: Attribution
- Elements of Argument from Horse of a Different Color: Composition and English Rhetoric. Authored by : Marianne Botos, Lynn McClelland, Stephanie Polliard, Pamela Osback . Located at : https://pvccenglish.files.wordpress.com/2010/09/eng-101-inside-pages-proof2-no-pro.pdf . License : CC BY: Attribution


7.6: Metabolism without Oxygen
- Discuss the fundamental difference between anaerobic cellular respiration and fermentation
- Describe the type of fermentation that readily occurs in animal cells and the conditions that initiate that fermentation
In aerobic respiration, the final electron acceptor is an oxygen molecule, O 2 . If aerobic respiration occurs, then ATP will be produced using the energy of high-energy electrons carried by NADH or FADH 2 to the electron transport chain. If aerobic respiration does not occur, NADH must be reoxidized to NAD + for reuse as an electron carrier for the glycolytic pathway to continue. How is this done? Some living systems use an organic molecule as the final electron acceptor. Processes that use an organic molecule to regenerate NAD + from NADH are collectively referred to as fermentation . In contrast, some living systems use an inorganic molecule as a final electron acceptor. Both methods are called anaerobic cellular respiration in which organisms convert energy for their use in the absence of oxygen.
Anaerobic Cellular Respiration
Certain prokaryotes, including some species of bacteria and Archaea, use anaerobic respiration. For example, the group of Archaea called methanogens reduces carbon dioxide to methane to oxidize NADH. These microorganisms are found in soil and in the digestive tracts of ruminants, such as cows and sheep. Similarly, sulfate-reducing bacteria and Archaea, most of which are anaerobic (Figure \(\PageIndex{1}\)), reduce sulfate to hydrogen sulfide to regenerate NAD + from NADH.
Lactic Acid Fermentation
The fermentation method used by animals and certain bacteria, like those in yogurt, is lactic acid fermentation (Figure \(\PageIndex{2}\)). This type of fermentation is used routinely in mammalian red blood cells and in skeletal muscle that has an insufficient oxygen supply to allow aerobic respiration to continue (that is, in muscles used to the point of fatigue). In muscles, lactic acid accumulation must be removed by the blood circulation and the lactate brought to the liver for further metabolism. The chemical reactions of lactic acid fermentation are the following:
\[\text{Pyruvic} \enspace \text{acid} + \text{NADH} \leftrightarrow \text{lactic} \enspace \text{acid} + \text{NAD}^+ \nonumber\]
The enzyme used in this reaction is lactate dehydrogenase (LDH). The reaction can proceed in either direction, but the reaction from left to right is inhibited by acidic conditions. Such lactic acid accumulation was once believed to cause muscle stiffness, fatigue, and soreness, although more recent research disputes this hypothesis. Once the lactic acid has been removed from the muscle and circulated to the liver, it can be reconverted into pyruvic acid and further catabolized for energy.
Tremetol, a metabolic poison found in the white snake root plant, prevents the metabolism of lactate. When cows eat this plant, it is concentrated in the milk they produce. Humans who consume the milk become ill. Symptoms of this disease, which include vomiting, abdominal pain, and tremors, become worse after exercise. Why do you think this is the case?
- Answer
-
The illness is caused by lactate accumulation. Lactate levels rise after exercise, making the symptoms worse. Milk sickness is rare today, but was common in the Midwestern United States in the early 1800s.
Alcohol Fermentation
Another familiar fermentation process is alcohol fermentation (Figure \(\PageIndex{3}\)) that produces ethanol, an alcohol. The first chemical reaction of alcohol fermentation is the following (CO 2 does not participate in the second reaction):
\[\text{Pyruvic} \enspace \text{acid} \rightarrow \ce{CO_2} + \text{acetaldehyde} + \text{NADH} \rightarrow \text{ethanol} + \text{NAD}^+ \nonumber\]
The first reaction is catalyzed by pyruvate decarboxylase, a cytoplasmic enzyme, with a coenzyme of thiamine pyrophosphate (TPP, derived from vitamin B 1 and also called thiamine). A carboxyl group is removed from pyruvic acid, releasing carbon dioxide as a gas. The loss of carbon dioxide reduces the size of the molecule by one carbon, making acetaldehyde. The second reaction is catalyzed by alcohol dehydrogenase to oxidize NADH to NAD + and reduce acetaldehyde to ethanol. The fermentation of pyruvic acid by yeast produces the ethanol found in alcoholic beverages. Ethanol tolerance of yeast is variable, ranging from about 5 percent to 21 percent, depending on the yeast strain and environmental conditions.
Other Types of Fermentation
Other fermentation methods occur in bacteria. Many prokaryotes are facultatively anaerobic. This means that they can switch between aerobic respiration and fermentation, depending on the availability of oxygen. Certain prokaryotes, like Clostridia , are obligate anaerobes. Obligate anaerobes live and grow in the absence of molecular oxygen. Oxygen is a poison to these microorganisms and kills them on exposure. It should be noted that all forms of fermentation, except lactic acid fermentation, produce gas. The production of particular types of gas is used as an indicator of the fermentation of specific carbohydrates, which plays a role in the laboratory identification of the bacteria. Various methods of fermentation are used by assorted organisms to ensure an adequate supply of NAD + for the sixth step in glycolysis. Without these pathways, that step would not occur and no ATP would be harvested from the breakdown of glucose.
Summary
If NADH cannot be oxidized through aerobic respiration, another electron acceptor is used. Most organisms will use some form of fermentation to accomplish the regeneration of NAD + , ensuring the continuation of glycolysis. The regeneration of NAD + in fermentation is not accompanied by ATP production; therefore, the potential of NADH to produce ATP using an electron transport chain is not utilized.
Review Questions
Which of the following fermentation methods can occur in animal skeletal muscles?
- lactic acid fermentation
- alcohol fermentation
- mixed acid fermentation
- propionic fermentation
- Answer
-
Answer: A
Free Response
What is the primary difference between fermentation and anaerobic respiration?
- Answer
-
Answer: Fermentation uses glycolysis only. Anaerobic respiration uses all three parts of cellular respiration, including the parts in the mitochondria like the citric acid cycle and electron transport; it also uses a different final electron acceptor instead of oxygen gas.
Glossary
- anaerobic cellular respiration
- process in which organisms convert energy for their use in the absence of oxygen
- fermentation
- process of regenerating NAD + with either an inorganic or organic compound serving as the final electron acceptor, occurs in the absence; occurs in the absence of oxygen
Contributors and Attributions
-
Connie Rye (East Mississippi Community College), Robert Wise (University of Wisconsin, Oshkosh), Vladimir Jurukovski (Suffolk County Community College), Jean DeSaix (University of North Carolina at Chapel Hill), Jung Choi (Georgia Institute of Technology), Yael Avissar (Rhode Island College) among other contributing authors. Original content by OpenStax (CC BY 4.0; Download for free at<EMAIL_ADDRESS>).


9.6: Distribution of Differences in Sample Proportions (3 of 5)
Learning Objectives
- Draw conclusions about a difference in population proportions from a simulation.
Now we continue with more examples of using a simulation to make inferences about differences in population proportions.
Example
Abecedarian Early Intervention Project
Recall the Abecedarian Early Intervention Project. In this experiment, researchers selected high-risk infants on the basis of the mothers’ education, family income, and other factors. They randomly assigned some infants to receive 5 years of high-quality preschool. The remaining infants were a control group. All children received nutritional supplements, social services, and health care to control the effects of these confounding factors on the outcomes of the experiment. By age 21, a much larger percentage of the treatment group than the control group had enrolled in college.
Assumption about parameters:
For this example, we assume that 45% of infants with a treatment similar to the Abecedarian project will enroll in college compared to 20% in the control group. We assume that a high-quality preschool experience will produce a 25% increase in college enrollment. We call this the treatment effect .
Let’s suppose that childcare institutions across the United States want to replicate the Abecedarian project. How much variation in results can we expect from fluctuation in random assignment to treatment groups? We know from our previous work that our answer depends on the number of infants we assign to each group.
Actual sample results:
Let’s suppose a daycare center replicates the Abecedarian project with 70 infants in the treatment group and 100 in the control group. After 21 years, the daycare center finds a 15% increase in college enrollment for the treatment group. This is still an impressive difference, but it is 10% less than the effect they had hoped to see. What can the daycare center conclude about the assumption that the Abecedarian treatment produces a 25% increase?
Here we use the simulation from the WalkThrough to do a simulation.
Analysis:
- We assume that the treatment effect is a 25% increase in college enrollment. So we see that the mean of the differences in sample proportions is 0.25. In other words, the differences in sample proportions average out to the difference between the population proportions.
- Typical differences from random assignment appear to fall between about 0.10 and 0.40. This is 2 standard errors from the mean.
- The daycare center achieved a 15% increase. This difference in sample proportions of 0.15 is less than 2 standard errors from the mean, so this result is not surprising if the treatment effect is really 25%.
Conclusion:
Chance variation that comes from random assignment explains the results from this daycare center. The results are not statistically significant. We can view this study as weak evidence that the treatment effect is less than 25%. So this study does not give us evidence strong enough to reject the claim that the Abecedarian treatment produces a 25% treatment effect.
Example
HPV Vaccine
During a debate between Republican presidential candidates in 2011, Michele Bachmann criticized an executive order made by her opponent, Texas Governor Rick Perry. The executive order required that all sixth-grade girls receive an HPV vaccine. HPV (human papillomavirus) infections are widespread. Some forms of HPV cause cancer. In 2007, the New England Journal of Medicine published the results of two large, randomized, placebo-controlled trials of a vaccine for HPV-related cancer. For the group of girls and women who received the vaccine, the HPV-related cancer rate was much lower than for those who received a placebo.
After the debate, a Congressional Connection Poll asked 1,000 people the following question: “As you may have heard, a few years ago the state of Texas required girls entering sixth grade to receive vaccinations against a virus that can cause cervical cancer in women. These injections were required for all girls unless their parent or legal guardian requested that they not receive them. Do you think Texas was right or wrong to require the vaccinations?” Fifty-seven percent of those polled answered that the state was wrong.
Let’s suppose 55% of all U.S. adults oppose mandatory vaccination against HPV. Let’s also suppose there is no difference between men and women on this issue. So we assume that 55% of all U.S. men and 55% of all U.S. women oppose mandatory vaccination against HPV.
Suppose we ask this same question to a random sample of 100 U.S. men and 150 U.S. women. How much of a difference in poll results will convince us that there are gender differences with this issue?
Use the simulation to do a simulation to answer this question. Enter your answer in the Try It activity that follows.
Click here to open this simulation in its own window.
Contributors and Attributions
- Concepts in Statistics. Provided by : Open Learning Initiative. Located at : http://oli.cmu.edu . License : CC BY: Attribution