7.10: Western Europe - The Rise of the Franks
At the west end of the Mediterranean and in northern Europe, the kingdom of the Franks would become the dominant power of the Christian kingdoms. Justinian’s armies had destroyed the Ostrogothic kingdom in Italy in the sixth-century Gothic War. A century and a half later, in 711, Arab Muslim invaders from North Africa conquered the Visigoth kingdom in Spain and established Muslim rule. From that time on, we refer to Muslim-ruled Spain of the early Middle Ages as al-Andalus. The destruction of these two kingdoms left the Franks as the dominant power of Western Europe. They were already the premier power in northern Gaul, but as the seventh century went on, they established themselves in southern Gaul as well, gradually subordinating other Germanic peoples to their rule.
The first dynasty of Frankish kings was known as the Merovingians , so named for Merovech, a possibly legendary ancestor of Clovis, the first Christian king of the Franks. The Franks’ power grew in Western Europe for several reasons. In the first place, the Frankish monarchy had fewer civil wars than did that of the Visigoths. The Frankish kingdom did face the weakness that it was sometimes divided among a king’s sons at his death (since Germanic peoples often looked at a kingdom as the king’s personal property), with warfare resulting within the divided kingdom. Nevertheless, although the kingdom might be split by inheritance and later reunited, there existed in general a strong sense of legitimate dynastic succession. In addition, the Catholic Church provided the Frankish monarchs with a sense of legitimacy as it had since the days of Clovis.
But as the Frankish kingdom expanded, many elements of what had characterized the Roman state continued to wither. One reason for this decline was that the nature of warfare had changed in Western Europe. Soldiers were no longer paid out of a government treasury; instead, they were rewarded with lands whose surplus they would use to outfit themselves with military equipment. The soldiers thus served as a warrior aristocracy. Even those families who had been Roman elites took up a military lifestyle in order to prosper in the new order. In addition, the Frankish kings increasingly made use of a pillage and gift system. In a pillage and gift system, a king or other war leader rewards his loyal soldiers by granting them gifts that came from the plunder of defeated enemies. With armies financed either by pillage and gift or by the wealth of an individual aristocrat’s lands, the Frankish kingdom had little reason for maintaining taxation. Moreover, the kingdom’s great landowners who supported the monarchy had a strong interest in seeing that they were not taxed efficiently; by the 580s, the Frankish government had simply ceased to update the old Roman tax registers.
One particular role that would gain prominence among the Frankish monarchy was that of the Major Domo , or Mayor of the Palace . The Mayor of the Palace was a noble who would grant out lands and gifts on behalf of the king and who would, in many cases, command the army. Gradually, one family of these Mayors of the Palace would rise to prominence above all other noble families in the Frankish kingdom: the Carolingians .
This dominant family’s more prominent members were named Charles, which in Latin is Carolus, hence the name Carolingians. By the mid-seventh century, the Carolingians had come to hold the position of Mayor of the Palace as a hereditary one. Over the early eighth century, the Carolingian Mayors of the Palace had become the actual rulers of the Frankish realm, while the Merovingian kings had little or no actual power. The earliest significant Carolingian major domo to dominate the Carolingian court was C harles Martel (r. 715 – 741). He was an able and effective military commander who—even though he rewarded his troops with lands taken from the Church—was able to show himself a defender of the Christian religion by defeating a Muslim attack on Gaul from al-Andalus in 732 at the Battle of Tours and by defeating the Saxons, who were at this point still largely pagans living in the forests to the northeast of the Frankish kingdom, in 738. These victories over both pagan and Muslim allowed for Martel to present his family as defenders of the Church and of the Christian religion in general.
Martel’s successor, Pepin the Short (r. 741 – 68), would take the final step towards wresting power away from the Merovingians and making his family the kings of the Franks. He followed in Martel’s footsteps in using the Church to shore up his legitimacy. He wrote to Pope Zachary I (r. 741 – 752), asking whether one who exercised the power of a king should have that power, or if instead the person with the name of king should have that power. Pope Zachary answered that kingship should rest with the person exercising its power—because a king ruled the earth on behalf of God, so a king who was not properly ruling was not doing his God-given duty. Thus the last Merovingian king was deposed by the combined powers of the Carolingian Mayors of the Palace and the popes. This close cooperation between Church and crown would go on to be a defining feature of the Frankish monarchy.
The relationship between the papacy and the Carolingians not only involved the popes legitimating Pepin’s coup d’état, but also included the Carolingian monarchs providing military assistance to the popes. Shortly after Zachary’s letter allowing Pepin to seize power, Pepin marched south to Italy to give the pope military assistance against the Lombards. He took control of several cities and their surrounding hinterlands and gave these cities as a gift to the papacy. The popes would thus rule a set of territories in central Italy known as the Papal States from Pepin’s day until the mid-nineteenth century.
The greatest of the Carolingians was the figure we refer to as Charlemagne , whose name means Charles the Great. As king of the Franks, he spent nearly the entirety of his reign leading his army in battle. To the southeast, he destroyed the khanate of the Avars, the nomadic people who had lived by raiding the Byzantine Empire. To the northeast of his realm, he subjugated the Saxons of Central Europe and had them converted to Christianity—a sometimes brutal process. When the Saxons rebelled in 782, he had 4,000 men executed in one day for having returned to their old religion. To the south in Italy, Charlemagne militarily conquered the Lombard kingdom and made himself its king. The only area in which he was less successful was in his invasion of al-Andalus. Although his forces seized control of several cities and fortresses in northeastern Spain (to include places like Barcelona), he was, on the whole, less successful against Spain’s Umayyad emirs. One reason for this lack of success was that, compared to Charlemagne’s other foes, al-Andalus was organized into a sophisticated state, and so better able to resist him.
By the end of the eighth century, Charlemagne ruled nearly all of Western Europe. Indeed, he ruled more of Western Europe than anyone since the Roman emperors of four centuries before. In the winter of 800, a mob expelled Pope Leo III from Rome. Charlemagne took his troops south of the Alps and restored the pope to his position in the Lateran palace, the palace complex to the northeast of Rome where the popes both lived and conducted most of their business.
On Christmas Day in 800, Charlemagne was attending worship at St. Peter’s Church. During that ceremony, the pope placed a crown upon Charlemagne’s head and declared him to be Roman emperor. Historians are not sure whether Charlemagne had planned this coronation or had simply gone up to the pope for a blessing and was surprised by this crown. The question of who had planned this coronation is controversial because the pope’s crowning the emperor could have been interpreted to mean that the crown was the pope’s to confer.
Indeed, it was around this time that a document known as the Donation of Constantine appeared in Western Europe. This document was a forgery—to this day, scholars do not know who forged it—that claimed to have been written by the Roman emperor Constantine (see Chapter Six). According to this forged document, the emperor Constantine had been cured of leprosy by Pope Sylvester I and, in thanks, had given the popes authority over all of the Western Empire. Although false, this document would go on to provide the popes with a claim to rule not just central Italy, but Western Europe as a whole.
Charlemagne’s coronation by the pope marked the culmination of the creation of a new society built on the wreck of the Western Roman Empire. This new society would be Christian and based on close cooperation of Church and State—although each would regard the others’ sphere of influence as separate.


8.13: Chapter 8 Summary
Speakers can memorably connect their message to an audience through careful planning, practice, and strategy regarding how they will deliver that message. Practice and preparation must be undertaken early and often. Start with a minimum of three separate practice sessions. The first session tests the amount of time the speech will take to deliver. The second session transfers the information from the outline to note cards. The third session familiarizes the speaker with his or her notes while working on delivery style. Any and all sessions of practice after that help to refine the delivery and potentially add many of the advanced tips offered in this chapter.
Public speaking and communication in general are learned skills that require dedication and commitment to refine and perfect.


7.7: Looking Ahead
In this chapter we became familiar with the processes that determine the humidity of the air, the process of formation and reasons for the geographical pattern of precipitation. The presence of moisture in the atmosphere and the geography of precipitation are dependent on the earth's energy balance, temperature, atmospheric pressure, and air circulation. This dependency reflects the interaction between the various spheres that comprise the earth system.
Chapters 4 through 7 deal with elements of weather and climate. They set the stage for chapter 8 "Weather Systems". In "Weather Systems" we'll focus on how the day-to-day changes in the atmosphere. Chapter 8 integrates the weather elements to explain the daily changes in atmospheric conditions. It will also examine the processes that create, and geographical patterns of, powerful storm systems like tornadoes and hurricanes.
Weather and climate are elements of physical geography that impact all of our lives. That's why an understanding of the potential effects of climate change is important to all of us. If we stay on our present course, geoscientists predict that storm systems in some parts of the world will become more severe. The patterns of both weather systems, and climates could radically shift, causing significant changes in natural habitats, agricultural systems, population distribution, and the economic stability. Geographers will be at the forefront of understanding how these changes will take place, where they will happen, and how we might address them.
Before proceeding to the Chapter 8, take some time to review chapter 7. You may wish to review chapter 5 "Air Temperature", and Chapter 6, as the contents of these chapters along with Chapter 7 comprise the components of weather systems.


10.2: Gaining Experience Inside and Outside the Classroom
An important part of your educational experience at HACC is to gain as much experience as you can, both inside the classroom as well as outside the classroom. You will gain valuable knowledge in the classroom through your required coursework. Gaining "hands-on" experience outside the classroom in the career field you are pursuing also is necessary to ensure you’re on the best path for your values, preferences and strengths. This hands-on experience can be done through work experience, community-based learning, volunteer work and/or internships.
If you have worked, whether part-time or full time, you have gained valuable work experience that contributes to building your resume and proving to employers you have transferable skills (refer to the Strengths chapter of this text). Most employers want to see some work experience in your background for evidence of these transferable skills. If you are planning to work while attending college, consider trying to get a job related to your career interest. Oftentimes taking an introductory course in college can help you get your foot in the door for an entry-level position. Connect with HACC’s Career Services for assistance with searching for a part-time or full-time job.
Some college courses at HACC integrate experiences, such as service-learning, observations, field work, and clinicals. If these experiences are extensive and provide you with transferable skills, list these experiences on your resume. You also can discuss these experiences in job interviews to show employers your skills.
Volunteer work is another great way for you to gain experience and network. Take a minute and view the following YouTube video titled "Volunteering May Help You Find Your Next Job." Video Volunteering May Help You Find Your Next Job [youtu.be]
The Value of Internships
Another way to gain valuable experience outside the classroom is through internships. Internships are short-term opportunities that allow students to gain valuable work experience in a particular career. In this course, you are asked to research different career possibilities using online research sources and informational interviews. Now is the time to consider doing a “test drive.” Deciding upon a career is difficult without trying out the work. Internships allow you to “test drive” your career of choice. The more you know and the more you experience, the more confident you will be with your career choice.
There are many benefits to participating in an internship:
- Internships allow you to gain valuable hands-on experience to help build your resume.
- An internship is a great way to confirm if the career you have selected is a good fit for you (or not).
- Internships provide you with opportunities to network and meet professionals in the industry you wish to join.
- Some employers hire their interns upon graduation.
Some internships are paid while others are unpaid. Regardless, the experience you gain is priceless. Oftentimes employers are looking to hire individuals with specific work experience. Having this work experience can be difficult for a recent college graduate, but internships provide necessary experience to build your resume and show employers you do have hands-on, industry-specific experience.
For information about finding an internship, please see HACC’s Career Services website: Career Services (hacc.edu)


10.2: The Simplicity of the Alternating Groups
Of special interest are groups with no nontrivial normal subgroups. Such groups are called simple groups . Of course, we already have a whole class of examples of simple groups, \({\mathbb Z}_p\text{,}\) where \(p\) is prime. These groups are trivially simple since they have no proper subgroups other than the subgroup consisting solely of the identity. Other examples of simple groups are not so easily found. We can, however, show that the alternating group, \(A_n\text{,}\) is simple for \(n \geq 5\text{.}\) The proof of this result requires several lemmas.
The alternating group \(A_n\) is generated by \(3\) -cycles for \(n \geq 3\text{.}\)
- Proof
-
To show that the \(3\)-cycles generate \(A_n\text{,}\) we need only show that any pair of transpositions can be written as the product of \(3\)-cycles. Since \((a, b) = (b, a)\text{,}\) every pair of transpositions must be one of the following:
\begin{align*} (a,b)(a,b) & = \identity\\ (a,b)(c,d) & = (a,c,b)(a,c,d)\\ (a,b)(a,c) & = (a,c,b)\text{.} \end{align*}
Let \(N\) be a normal subgroup of \(A_n\text{,}\) where \(n \geq 3\text{.}\) If \(N\) contains a \(3\) -cycle, then \(N = A_n\text{.}\)
- Proof
-
We will first show that \(A_n\) is generated by \(3\)-cycles of the specific form \((i,j,k)\text{,}\) where \(i\) and \(j\) are fixed in \(\{ 1, 2, \ldots, n \}\) and we let \(k\) vary. Every \(3\)-cycle is the product of \(3\)-cycles of this form, since
\begin{align*} (i, a, j) & = (i, j, a)^2\\ (i, a, b) & = (i, j, b) (i, j, a)^2\\ (j, a, b) & = (i, j, b)^2 (i, j, a)\\ (a, b, c) & = (i, j, a)^2 (i, j, c) (i, j, b)^2 (i, j, a)\text{.} \end{align*}Now suppose that \(N\) is a nontrivial normal subgroup of \(A_n\) for \(n \geq 3\) such that \(N\) contains a \(3\)-cycle of the form \((i, j, a)\text{.}\) Using the normality of \(N\text{,}\) we see that
\[ [(i, j)(a, k)](i, j, a)^2 [(i, j)(a, k)]^{-1} = (i, j, k) \nonumber \]is in \(N\text{.}\) Hence, \(N\) must contain all of the \(3\)-cycles \((i, j, k)\) for \(1 \leq k \leq n\text{.}\) By Lemma \(10.8\), these \(3\)-cycles generate \(A_n\text{;}\) hence, \(N = A_n\text{.}\)
For \(n \geq 5\text{,}\) every nontrivial normal subgroup \(N\) of \(A_n\) contains a \(3\) -cycle.
- Proof
-
Let \(\sigma\) be an arbitrary element in a normal subgroup \(N\text{.}\) There are several possible cycle structures for \(\sigma\text{.}\)
\(\sigma\) is a \(3\)-cycle. \(\sigma\) is the product of disjoint cycles, \(\sigma = \tau(a_1, a_2, \ldots, a_r) \in N\text{,}\) where \(r \gt 3\text{.}\) \(\sigma\) is the product of disjoint cycles, \(\sigma = \tau(a_1, a_2, a_3)(a_4, a_5, a_6)\text{.}\) \(\sigma = \tau(a_1, a_2, a_3)\text{,}\) where \(\tau\) is the product of disjoint 2-cycles. \(\sigma = \tau (a_1, a_2) (a_3, a_4)\text{,}\) where \(\tau\) is the product of an even number of disjoint 2-cycles.\[ \mu^{-1} (a_1, a_3)(a_2, a_4) \mu (a_1, a_3)(a_2, a_4) \in N \nonumber \]and
\begin{align*} \mu^{-1} (a_1, a_3)(a_2, a_4) \mu (a_1, a_3)(a_2, a_4) & = (a_1, b a_3)(a_1, a_3)(a_2, a_4) (a_1, a_3, b)(a_1, a_3)(a_2, a_4)\\ & = (a_1 a_3 b )\text{.} \end{align*}Therefore, \(N\) contains a \(3\)-cycle. This completes the proof of the lemma.
If \(\sigma\) is a \(3\)-cycle, then we are done. If \(N\) contains a product of disjoint cycles, \(\sigma\text{,}\) and at least one of these cycles has length greater than 3, say \(\sigma = \tau(a_1, a_2, \ldots, a_r)\text{,}\) then
\[ (a_1, a_2, a_3)\sigma(a_1, a_2, a_3)^{-1} \nonumber \]is in \(N\) since \(N\) is normal; hence,
\[ \sigma^{-1}(a_1, a_2, a_3)\sigma(a_1, a_2, a_3)^{-1} \nonumber \]is also in \(N\text{.}\) Since
\begin{align*} \sigma^{-1}(a_1, a_2, a_3)\sigma(a_1, a_2, a_3)^{-1} & = \sigma^{-1}(a_1, a_2, a_3)\sigma(a_1, a_3, a_2)\\ & = (a_1, a_2, \ldots, a_r)^{-1}\tau^{-1}(a_1, a_2, a_3) \tau(a_1, a_2, \ldots, a_r)(a_1, a_3, a_2)\\ & = (a_1, a_r, a_{r-1}, \ldots, a_2 )(a_1, a_2, a_3) (a_1, a_2, \ldots, a_r)(a_1, a_3, a_2)\\ & = (a_1, a_3, a_r)\text{,} \end{align*}\(N\) must contain a \(3\)-cycle; hence, \(N = A_n\text{.}\)
Now suppose that \(N\) contains a disjoint product of the form
\[ \sigma = \tau(a_1, a_2, a_3)(a_4, a_5, a_6)\text{.} \nonumber \]Then
\[ \sigma^{-1}(a_1, a_2, a_4)\sigma(a_1, a_2, a_4)^{-1} \in N \nonumber \]since
\[ (a_1, a_2, a_4)\sigma(a_1, a_2, a_4)^{-1} \in N\text{.} \nonumber \]So
\begin{align*} \sigma^{-1}(a_1, a_2, a_4) \sigma(a_1, a_2, a_4)^{-1} & = [ \tau (a_1, a_2, a_3) (a_4, a_5, a_6) ]^{-1} (a_1, a_2, a_4) \tau (a_1, a_2, a_3) (a_4, a_5, a_6) (a_1, a_2, a_4)^{-1}\\ & = (a_4, a_6, a_5) (a_1, a_3, a_2) \tau^{-1}(a_1, a_2, a_4) \tau (a_1, a_2, a_3) (a_4, a_5, a_6) (a_1, a_4, a_2)\\ & = (a_4, a_6, a_5)(a_1, a_3, a_2) (a_1, a_2, a_4) (a_1, a_2, a_3) (a_4, a_5, a_6)(a_1, a_4, a_2)\\ & = (a_1, a_4, a_2, a_6, a_3)\text{.} \end{align*}So \(N\) contains a disjoint cycle of length greater than 3, and we can apply the previous case.
Suppose \(N\) contains a disjoint product of the form \(\sigma = \tau(a_1, a_2, a_3)\text{,}\) where \(\tau\) is the product of disjoint 2-cycles. Since \(\sigma \in N\text{,}\) \(\sigma^2 \in N\text{,}\) and
\begin{align*} \sigma^2 & = \tau(a_1, a_2, a_3)\tau(a_1, a_2, a_3)\\ & =(a_1, a_3, a_2)\text{.} \end{align*}So \(N\) contains a \(3\)-cycle.
The only remaining possible case is a disjoint product of the form
\[ \sigma = \tau (a_1, a_2) (a_3, a_4)\text{,} \nonumber \]where \(\tau\) is the product of an even number of disjoint \(2\)-cycles. But
\[ \sigma^{-1}(a_1, a_2, a_3)\sigma(a_1, a_2, a_3)^{-1} \nonumber \]is in \(N\) since \((a_1, a_2, a_3)\sigma(a_1, a_2, a_3)^{-1}\) is in \(N\text{;}\) and so
\begin{align*} \sigma^{-1}(a_1, a_2, a_3)\sigma(a_1, a_2, a_3)^{-1} & = \tau^{-1} (a_1, a_2) (a_3, a_4) (a_1, a_2, a_3) \tau (a_1, a_2)(a_3, a_4)(a_1, a_2, a_3)^{-1}\\ & = (a_1, a_3)(a_2, a_4)\text{.} \end{align*}Since \(n \geq 5\text{,}\) we can find \(b \in \{1, 2, \ldots, n \}\) such that \(b \neq a_1, a_2, a_3, a_4\text{.}\) Let \(\mu = (a_1, a_3, b)\text{.}\) Then
The alternating group, \(A_n\text{,}\) is simple for \(n \geq 5\text{.}\)
- Proof
-
Let \(N\) be a normal subgroup of \(A_n\text{.}\) By Lemma \(10.10\), \(N\) contains a \(3\)-cycle. By Lemma \(10.9\), \(N = A_n\text{;}\) therefore, \(A_n\) contains no proper nontrivial normal subgroups for \(n \geq 5\text{.}\)
Historical Note
One of the foremost problems of group theory has been to classify all simple finite groups. This problem is over a century old and has been solved only in the last few decades of the twentieth century. In a sense, finite simple groups are the building blocks of all finite groups. The first nonabelian simple groups to be discovered were the alternating groups. Galois was the first to prove that \(A_5\) was simple. Later, mathematicians such as C. Jordan and L. E. Dickson found several infinite families of matrix groups that were simple. Other families of simple groups were discovered in the 1950s. At the turn of the century, William Burnside conjectured that all nonabelian simple groups must have even order. In 1963, W. Feit and J. Thompson proved Burnside's conjecture and published their results in the paper “Solvability of Groups of Odd Order,” which appeared in the Pacific Journal of Mathematics . Their proof, running over 250 pages, gave impetus to a program in the 1960s and 1970s to classify all finite simple groups. Daniel Gorenstein was the organizer of this remarkable effort. One of the last simple groups was the “Monster,” discovered by R. Greiss. The Monster, a \(196{,}833 \times 196{,}833\) matrix group, is one of the 26 sporadic, or special, simple groups. These sporadic simple groups are groups that fit into no infinite family of simple groups. Some of the sporadic groups play an important role in physics.


2.4: Toulmin’s Schema
Stephen Edelston Toulmin (born March 25, 1922) is a British philosopher, author, and educator. Influenced by the Austrian philosopher Ludwig Wittgenstein, Toulmin devoted his works to the analysis of moral reasoning. Throughout his writings, he seeks to develop practical arguments which can be used effectively in evaluating the ethics behind moral issues. The Toulmin Model of Argumentation, a diagram containing six interrelated components used for analyzing arguments, was considered his most influential work, particularly in the field of rhetoric and communication, and in computer science.
Stephen Toulmin is a British philosopher and educator who devoted to analyzing moral reasoning. Throughout his writings, he seeks to develop practical arguments which can be used effectively in evaluating the ethics behind moral issues. His most famous work was his Model of Argumentation(sometimes called “Toulmin’s Schema,” which is a method of analyzing an argument by breaking it down into six parts. Once an argument is broken down and examined, weaknesses in the argument can be found and addressed.
Toulmin’s Schema:
- Claim: conclusions whose merit must be established. For example, if a person tries to convince a listener that he is a British citizen, the claim would be “I am a British citizen.”
- Data: the facts appealed to as a foundation for the claim. For example, the person introduced in 1 can support his claim with the supporting data “I was born in Bermuda.”
- Warrant: the statement authorizing the movement from the data to the claim. In order to move from the data established in 2, “I was born in Bermuda,” to the claim in 1, “I am a British citizen,” the person must supply a warrant to bridge the gap between 1 & 2 with the statement “A man born in Bermuda will legally be a British Citizen.” Toulmin stated that an argument is only as strong as its weakest warrant and if a warrant isn’t valid, then the whole argument collapses. Therefore, it is important to have strong, valid warrants.
- Backing: facts that give credibility to the statement expressed in the warrant; backing must be introduced when the warrant itself is not convincing enough to the readers or the listeners. For example, if the listener does not deem the warrant as credible, the speaker would supply legal documents as backing statement to show that it is true that “A man born in Bermuda will legally be a British Citizen.”
- Rebuttal: statements recognizing the restrictions to which the claim may legitimately be applied. The rebuttal is exemplified as follows, “A man born in Bermuda will legally be a British citizen, unless he has betrayed Britain and become a spy of another country.”
- Qualifier: words or phrases expressing how certain the author/speaker is concerning the claim. Such words or phrases include “possible,” “probably,” “impossible,” “certainly,” “presumably,” “as far as the evidence goes,” or “necessarily.” The claim “I am definitely a British citizen” has a greater degree of force than the claim “I am a British citizen, presumably.”
- The first three elements “claim,” “data,” and “warrant” are considered as the essential components of practical arguments, while the 4-6 “Qualifier,” “Backing,” and “Rebuttal” may not be needed in some arguments. When first proposed, this layout of argumentation is based on legal arguments and intended to be used to analyze arguments typically found in the courtroom; in fact, Toulmin did not realize that this layout would be applicable to the field of rhetoric and communication until later. 1
Here are a few more examples of Toulmin’s Schema:
Suppose you see a one of those commercials for a product that promises to give you whiter teeth. Here are the basic parts of the argument behind the commercial:
- Claim: You should buy our tooth-whitening product.
- Data: Studies show that teeth are 50% whiter after using the product for a specified time.
- Warrant: People want whiter teeth.
- Backing: Celebrities want whiter teeth.
- Rebuttal: Commercial says “unless you don’t want to attract guys.”
- Qualifier: Fine print says “product must be used six weeks for results.”
Notice that those commercials don’t usually bother trying to convince you that you want whiter teeth; instead, they assume that you have bought into the value our culture places on whiter teeth. When an assumption–a warrant in Toulmin’s terms–is unstated, it’s called an implicit warrant. Sometimes, however, the warrant may need to be stated because it is a powerful part of the argument. When the warrant is stated, it’s called an explicit warrant. 2
Another example:
- Claim: People should probably own a gun.
- Data: Studies show that people who own a gun are less likely to be mugged.
- Warrant: People want to be safe.
- Backing: May not be necessary. In this case, it is common sense that peoplewant to be safe.
- Rebuttal: Not everyone should own a gun. Children and those will mentaldisorders/problems should not own a gun.
- Qualifier: The word “probably” in the claim.
- Claim: Flag burning should be unconstitutional in most cases.
- Data: A national poll says that 60% of Americans want flag burningunconstitutional
- Warrant: People want to respect the flag.
- Backing: Official government procedures for the disposal of flags.
- Rebuttal: Not everyone in the U.S. respects the flag.
- Qualifier: The phrase “in most cases”
Toulmin says that the weakest part of any argument is its weakest warrant. Remember that the warrant is the link between the data and the claim. If the warrant isn’t valid, the argument collapses. 2
Contributors and Attributions
- Toulmin's Schema. Provided by : Utah State University OpenCourseWare. Located at : ocw.usu.edu/english/intermediate-writing/english-2010/-2010/toulmins-schema.html. License : CC BY-NC-SA: Attribution-NonCommercial-ShareAlike
- Image of flowchart. Authored by : Chiswick Chap. Located at : http://commons.wikimedia.org/wiki/File:Toulmin_Argumentation_Example.gif . License : CC BY-SA: Attribution-ShareAlike
- Image of woman with white teeth. Authored by : Harsha K R. Located at : https://flic.kr/p/5s24kK . License : CC BY-SA: Attribution-ShareAlike


6.2: The Upper Limbs
Information
For anatomists, the upper limb consists of the arm (the upper arm), the forearm (the lower arm), and the hand. The arm consists of a single bone, the humerus. The forearm consists of two bones, the ulna and radius. And the hand consists of 27 bones, which are grouped into the phalanges, metacarpals, and carpals.
The major processes and markings of the humerus, ulna , and radius bones are shown in Figures \(\PageIndex{2}\), \(\PageIndex{3}\), and \(\PageIndex{4}\), respectively.
The bones of the hands are divided into three groups. The carpals articulate with the ulna and radius bones of the forearm and are named after the carpus, or wrist. There are 8 carpal bones and each has its own name. In Figure \(\PageIndex{5}\) they are numbered so that 1-trapezium, 2-trapezoid, 3-capitate, 4-hamate, 5-pisiform, 6-triquetrum, 7-lunate, 8- scaphoid.
The metacarpals are five individual bones that are wrapped in muscle and collective tissue to create a single solid mass that serves as the palm of the hand. They are numbered I – V, starting with the metacarpal under the thumb and moving sequentially to the little finger.
Metacarpals are individually named according to the hand they come from and their number. So the metacarpal under the little finger in Figure 6.9 is named left metacarpal V.
There are 14 bones that make up the fingers. All are called phalange s (singular is phalanx ).  Each thumb only has two phalanges, labelled proximal and distal. The phalanges are numbered I through V, like the metacarpals. Each phalanx then is named according to which hand it comes from, which number it is, and whether it is proximal, middle, or distal. So the second phalanx on the pointing finger in Figure is the left medial phalanx II.
LAB 6 EXERCISE \(\PageIndex{1}\):
- Using one of the full skeletons in the room, fill out the table below with three or four steps to determine whether an individual bone comes from the anatomical left or anatomical right. You must use any features that are already filled in.
- You can describe any features on that bone and which direction it has to face to allow you to determine whether that particular bone came from anatomical left or anatomical right.
- Sample instructions for the clavicle are provided as an example for all subsequent exercises. Use proper anatomical terminology. Use terms which will make sense to anyone schooled in anatomy if they read it. Use as many steps as you need, not necessarily four.
Humerus – Anatomical left from anatomical right.
1. Olecranon fossa -
2.
3.
4.
Ulna – Anatomical left from anatomical right.
1. Radial notch -
2.
3.
4.
Radius – Anatomical left from anatomical right.
1. Styloid process -
2.
3.
4.
LICENSES AND ATTRIBUTIONS
CC LICENSED CONTENT, ORIGINAL
A&P Labs. Authored by : Ross Whitwam. Provided by : Mississippi University for Women. Located at : http://www.muw.edu . License : CC BY-SA: Attribution-ShareAlike
Fig \(\PageIndex{1}\):. The bones of the left upper limb.. Authored by : Images in Figure 7-8 were made out of, or made from, content published in a BodyParts3D/Anatomography web site. The content of their website is published under the Creative Commons Attribution 2.1 Japan license. The author and licenser of the contents is http://lifesciencedb.jp/bp3d/?lng=en. Located at : http://lifesciencedb.jp/bp3d/?lng=en . License: CC BY-SA: Attribution-ShareAlike
Figure \(\PageIndex{2}\):. The left humerus and its various processes and markings.. Authored by : Images in Figure 7-9 were made out of, or made from, content published in a BodyParts3D/Anatomography web site. The content of their website is published under the Creative Commons Attribution 2.1 Japan license. The author and licenser of the contents is http://lifesciencedb.jp/bp3d/?lng=en. Located at : http://lifesciencedb.jp/bp3d/?lng=en . License: CC BY-SA: Attribution-ShareAlike
Figure \(\PageIndex{3}\):. The left ulna (in brown) and its major markings and processes.. Authored by : Images in Figure 7-10 were made out of, or made from, content published in a BodyParts3D/Anatomography web site. The content of their website is published under the Creative Commons Attribution 2.1 Japan license. The author and licenser of the contents is http://lifesciencedb.jp/bp3d/?lng=en . Located at : http://lifesciencedb.jp/bp3d/?lng=en . License : CC BY-SA: Attribution- ShareAlike
Figure \(\PageIndex{4}\):. The left radius (in brown) and its major markings and processes.. Authored by : Images in Figure 7-11 were made out of, or made from, content published in a BodyParts3D/Anatomography web site. The content of their website is published under the Creative Commons Attribution 2.1 Japan license. The author and licenser of the contents is http://lifesciencedb.jp/bp3d/?lng=en . Located at : http://lifesciencedb.jp/bp3d/?lng=en . License : CC BY-SA: Attribution- ShareAlike
Figure \(\PageIndex{5}\):. The bones of the left hand.. Authored by : Images in Figure 7-12 were made out of, or made from, content published in a BodyParts3D/Anatomography web site. The content of their website is published under the Creative Commons Attribution 2.1 Japan license. The author and licenser of the contents is http://lifesciencedb.jp/bp3d/?lng=en. Located at : http://lifesciencedb.jp/bp3d/?lng=en . License: CC BY-SA: Attribution-ShareAlike


1.10: Week 10 - Visual Arguments, Media and Advertising
In the modern era, not all arguments come to us in the form of words: written or spoken. Increasingly, images play an important role in the development and understanding of arguments. This unit explores how visual arguments are constructed and employed to sustain and bolster other forms of argument. This week, we will be exploring the use of visuals (images, charts, graphs, etc.) in the presentation of arguments. Like any other piece of support, images and other visuals are compelling when used correctly. They also can be used in ways that contribute to all of the flaws, fallacies and faulty reasoning we have been exploring all term.
The Venn diagram above is a great example of how an image can be used effectively to communicate a complicated idea rather quickly and efficiently. Here, we can see that “sustainability” is defined as the intersection of environmental, economic and social concerns, for instance. Proper use of visuals can help us connect with an audience’s emotions and values, build credibility and share data and logical information in memorable and engaging ways.
- View the film: The Codes of Gender
- View the film: Generation Like https://www.youtube.com/watch?v=JqamKb7gTWY
- View the video: Visual Arguments Essay https://www.youtube.com/watch?v=4rudEk92goc
- Use the outside link: Visual Arguments https://www.youtube.com/watch?v=xCYf3J88EzA
- Review the handout: Ideographs


12.6: References
Astrella, J. A. (2017). Return on investment. JONA: The Journal of Nursing Administration , 47 (7/8), 379–383. https://doi.org/10.1097/nna.0000000000000499
Baicker, K., Cutler, D., & Song, Z. (2010). Workplace wellness programs can generate savings. Health Affairs , 29 (2), 304–311. https://doi.org/10.1377/hlthaff.2009.0626
BLS. (2020, April). Workplace violence in healthcare, 2018 : U.S. Bureau of Labor Statistics . Bureau of Labor Statistics. https://www.bls.gov/iif/factsheets/w...hcare-2018.htm
BLS. (2023a). IIF home . U.S. Bureau of Labor Statistics. https://www.bls.gov/iif/home.htm
BLS. (2023b). National census of fatal occupational injuries in 2022 . Bureau of Labor Statistics, U.S. Department of Labor. https://www.bls.gov/news.release/pdf/cfoi.pdf
BLS. (2024, July 5). Table A-1. Employment status of the civilian population by sex and age - 2024 Q02 Results . Bureau of Labor Statistics. https://www.bls.gov/news.release/empsit.t01.htm
CDC. (2021, May 12). Workplace health model . CDC. https://www.cdc.gov/workplacehealthp...del/index.html
CDC. (2024, May 30). About workplace violence . Violence. https://www.cdc.gov/niosh/violence/about/
CDC/NIOSH. (2022, August 11). Fast facts- traumatic occupational injuries . CDC. https://www.cdc.gov/niosh/injury/fastfacts.html
Duffy, E. Y., Hiremath, P. G., Martinez-Amezcua, P., Safeer, R., Schrack, J. A., Blaha, M. J., Michos, E. D., Blumenthal, R. S., Martin, S. S., & Cainzos-Achirica, M. (2021). Opportunities to improve cardiovascular health in the new American workplace. American Journal of Preventive Cardiology , 5 , 100136. https://doi.org/10.1016/j.ajpc.2020.100136
Grand View Research. (2022). Corporate wellness market size & share report, 2023-2030 . Grand View Research. https://www.grandviewresearch.com/in...ellness-market
Guyton, G. P. (1999). A Brief History of Worker’s Compensation. Iowa Orthopedic Journal , 19 , 106–110. PubMed Central.
Horn, D., Randle, N. W., & McNeil, S. R. (2020///Winter). A Cross-Disciplinary Framework to Measure Workplace Wellness Program Success: Quarterly Journal. S.A.M.Advanced Management Journal, 85(1), 4-12. https://libwin2k.glendale.edu/login?url=https://www.proquest.com/scholarly-journals/cross-disciplinary-framework-measure-workplace/docview/2708789994/se-2
ILO. (2024a). Up-to-date conventions and recommendations . International Labour Organization, a United Nations Agency; NORMLEX Information System on International Labour Standards. https://normlex.ilo.org/dyn/normlex/en/f?p=1000:12020 ::::::
ILO. (2024b, January 28). Child labour . International Labour Organization. https://www.ilo.org/topics/child-labour#factoids
Lerner, D., Rodday, A. M., Cohen, J. T., & Rogers, W. H. (2013). A systematic review of the evidence concerning the economic impact of employee-focused health promotion and wellness programs. Journal of Occupational & Environmental Medicine , 55 (2), 209–222. https://doi.org/10.1097/jom.0b013e3182728d3c
Manzo IV, F., Jekot, M., & Bruno, R., PhD. (2021). The Impact of Unions on Construction Worksite Health and Safety. Illinois Economic Policy Institute .
Marin-Farrona, M., Wipfli, B., Thosar, S. S., Colino, E., Garcia-Unanue, J., Gallardo, L., Felipe, J. L., & López-Fernández, J. (2023). Effectiveness of worksite wellness programs based on physical activity to improve workers’ health and productivity: A systematic review. Systematic Reviews , 12 (1). https://doi.org/10.1186/s13643-023-02258-6
Maryville University. (2023, February 28). What is the gig economy, and who are its workers? Maryville University Online. https://online.maryville.edu/blog/wh...e-gig-economy/
Mattke, S., Liu, H., Caloyeras, J. P., Huang, C. Y., Van Busum, K. R., Khodyakov, D., & Shier, V. (2013). Workplace Wellness Programs Study Final Report . RAND Health. https://www.dol.gov/sites/dolgov/fil...-full-text.pdf
Mikolajczyk, S. (2022, July 28). Workers’ compensation for agricultural workers . National Agricultural Law Center. https://nationalaglawcenter.org/work...tural-workers/
National Safety Council. (2024a). Work injury costs . Injury Facts; National Safety Council. https://injuryfacts.nsc.org/work/cos...-injury-costs/
National Safety Council. (2024b). Workplace violence . National Safety Council. https://www.nsc.org/workplace/safety...place-violence
OSHA. (n.d.-a). Commonly used statistics . Occupational Safety and Health Administration. Retrieved July 15, 2024, from https://www.osha.gov/data/commonstats
OSHA. (n.d.-b). OSHA at 50 . Occupational Safety and Health Administration. Retrieved July 9, 2024, from https://www.osha.gov/osha50/
OSHA. (n.d.-c). Young workers - Real stories . Occupational Safety and Health Administration. Retrieved July 10, 2024, from https://www.osha.gov/young-workers/real-stories
Peñalvo, J. L., Sagastume, D., Mertens, E., Uzhova, I., Smith, J., Wu, J. H. Y., Bishop, E., Onopa, J., Shi, P., Micha, R., & Mozaffarian, D. (2021). Effectiveness of workplace wellness programmes for dietary habits, overweight, and cardiometabolic health: A systematic review and meta-analysis. The Lancet Public Health , 6 (9), e648–e660. https://doi.org/10.1016/s2468-2667(21)00140-7
Riley, K., Wilhalme, H., Delp, L., & Eisenman, D. (2018). Mortality and morbidity during extreme heat events and prevalence of outdoor work: An analysis of community-level data from Los Angeles County, California. International Journal of Environmental Research and Public Health , 15 (4), 580. https://doi.org/10.3390/ijerph15040580
Schuman, M. (2017a, January). History of child labor in the United States—part 1: Little children working : Monthly Labor Review: U.S. Bureau of Labor Statistics . Bureau of Labor Statistics; Monthly Labor Review. https://www.bls.gov/opub/mlr/2017/ar...tes-part-1.htm
Schuman, M. (2017b, January). History of child labor in the United States—part 2: The reform movement : Monthly Labor Review: U.S. Bureau of Labor Statistics . Bureau of Labor Statistics. https://www.bls.gov/opub/mlr/2017/ar...m-movement.htm
Seabert, D., McKenzie, J. F., & Pinger, R. R. (2021). McKenzie’s an introduction to community & public health . Jones & Bartlett Learning.
Sherer, J., & Mast, N. (2023, December 21). Child labor laws are under attack in states across the country: Amid increasing child labor violations, lawmakers must act to strengthen standards . Economic Policy Institute. https://www.epi.org/publication/chil...-under-attack/
Shi, & Singh, D. A. (2017). Delivering health care in america . Jones & Bartlett Learning.
Tiesman, H. M., Hendricks, S. A., Wiegand, D. M., Lopes-Cardozo, B., Rao, C. Y., Horter, L., Rose, C. E., & Byrkit, R. (2023). Workplace violence and the mental health of public health workers during COVID-19. American Journal of Preventive Medicine , 64 (3), 315–325. https://doi.org/10.1016/j.amepre.2022.10.004
U.N. Department of Economic and Social Affairs. (2023). Goal 8 . United Nations Department of Economic and Social Affairs. https://sdgs.un.org/goals/goal8
Vankar, P. (2022, November 16). Companies offering health/wellness programs by firm size 2021 . Statista. https://www.statista.com/statistics/...taining-costs/


50.6: Antibodies in Medical Treatment and Diagnosis
Many laboratory tests are designed to confirm a presumptive diagnosis by detecting antibodies specific to a suspected pathogen. Unfortunately, many such tests are time-consuming and expensive. That is now changing, however, with the development of new, miniaturized technologies that are fast and inexpensive. For example, researchers at Columbia University are developing a “lab-on-a-chip” technology that will test a single drop of blood for 15 different infectious diseases, including HIV and syphilis, in a matter of minutes. 1 The blood is pulled through tiny capillaries into reaction chambers where the patient’s antibodies mix with reagents. A chip reader that attaches to a cell phone analyzes the results and sends them to the patient’s healthcare provider. Currently the device is being field tested in Rwanda to check pregnant women for chronic diseases. Researchers estimate that the chip readers will sell for about $100 and individual chips for $1. 2
-
- 50.6.1: Practical Applications of Monoclonal and Polyclonal Antibodies
- In addition to being crucial for our normal immune response, antibodies provide powerful tools for research and diagnostic purposes. The high specificity of antibodies makes them an excellent tool for detecting and quantifying a broad array of targets, from drugs to serum proteins to microorganisms. With in vitro assays, antibodies can be used to precipitate soluble antigens, agglutinate cells, and neutralize drugs, toxins, and viruses.
-
- 50.6.2: Detecting Antigen-Antibody Complexes in vitro
- Laboratory tests to detect antibodies and antigens outside of the body (e.g., in a test tube) are called in vitro assays. When both antibodies and their corresponding antigens are present in a solution, we can often observe a precipitation reaction in which large complexes (lattices) form and settle out of solution. In the next several sections, we will discuss several common in vitro assays.
-
- 50.6.3: Agglutination Assays
- In addition to causing precipitation of soluble molecules and flocculation of molecules in suspension, antibodies can also clump together cells or particles (e.g., antigen-coated latex beads) in a process called agglutination. Agglutination can be used as an indicator of the presence of antibodies against bacteria or red blood cells. Agglutination assays are usually quick and easy to perform on a glass slide or microtiter plate.
-
- 50.6.4: Fluorescent Auto-Antibody Techniques
- Rapid visualization of bacteria from a clinical sample such as a throat swab or sputum can be achieved through fluorescent antibody (FA) techniques that attach a fluorescent marker (fluorogen) to the constant region of an antibody, resulting in a reporter molecule that is quick to use, easy to see or measure, and able to bind to target markers with high specificity. We can also label cells, allowing us to precisely quantify particular subsets of cells or even purify them for further research.
Footnotes
- 1 Chin, Curtis D. et al., “Mobile Device for Disease Diagnosis and Data Tracking in Resource-Limited Settings,” Clinical Chemistry 59, no. 4 (2013): 629-40.
- 2 Evarts, H., “Fast, Low-Cost Device Uses the Cloud to Speed Up Testing for HIV and More,” January 24, 2013. Accessed July 14, 2016. http://engineering.columbia.edu/fast...g-hiv-and-more .
Thumbnail: Enzyme-linked antibodies against CD8 were used to stain the CD8 cells in this preparation of bone marrow using a chromogen. (credit: modification of work by Yamashita M, Fujii Y, Ozaki K, Urano Y, Iwasa M, Nakamura S, Fujii S, Abe M, Sato Y, Yoshino T).


5.9: Introduction to Managerial Accounting Perspectives
What you’ll learn to do: Examine the various managerial accounting perspectives throughout an organization
Within all organizations, various people will need different information from the management accounting systems. Since managerial accounting does not need to follow GAAP and the information prepared is only for internal use, the same information can be manipulated in a variety of ways to help managers to save money, manage costs, price products and make a company more profitable.
Various strategies can be implemented by different companies as well. Not all companies are looking at making the cheapest product at the lowest cost! Some are looking at ways to make a premium product with a very targeted market. The strategies used by these companies will be different.
However a company culture is developed and how strategies are planned, they all start at the top of a company. Leadership style trickles down through the organization and can be seen at all levels.


30.7: Summary
30.1 The Cosmic Context for Life
Life on Earth is based on the presence of a key unit known as an organic molecule, a molecule that contains carbon, especially complex hydrocarbons. Our solar system formed about 5 billion years ago from a cloud of gas and dust enriched by several generations of heavier element production in stars. Life is made up of chemical combinations of these elements made by stars. The Copernican principle, which suggests that there is nothing special about our place in the universe, implies that if life could develop on Earth, it should be able to develop in other places as well. The Fermi paradox asks why, if life is common, more advanced life-forms have not contacted us.
30.2 Astrobiology
The study of life in the universe, including its origin on Earth, is called astrobiology. Life as we know it requires water, certain elemental raw materials (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur), energy, and an environment in which the complex chemistry of life is stable. Carbon-based (or organic) molecules are abundant in space and may also have been produced by processes on Earth. Life appears to have spread around our planet within 400 million years after the end of heavy bombardment, if not sooner. The actual origin of life—the processes leading from chemistry to biology—is not completely understood. Once life took hold, it evolved to use many energy sources, including first a range of different chemistries and later light, and diversified across a range of environmental conditions that humans consider “extreme.” This proliferation of life into so many environmental niches, so relatively soon after our planet became habitable, has served to make many scientists optimistic about the chances that life could exist elsewhere.
30.3 Searching for Life beyond Earth
The search for life beyond Earth offers several intriguing targets. Mars appears to have been more similar to Earth during its early history than it is now, with evidence for liquid water on its ancient surface and perhaps even now below ground. The accessibility of the martian surface to our spacecraft offers the exciting potential to directly examine ancient and modern samples for evidence of life. In the outer solar system, the moons Europa and Enceladus likely host vast sub-ice oceans that may directly contact the underlying rocks—a good start in providing habitable conditions—while Titan offers a fascinating laboratory for understanding the sorts of organic chemistry that might ultimately provide materials for life. And the last decade of research on exoplanets leads us to believe that there may be billions of habitable planets in the Milky Way Galaxy. Study of these worlds offers the potential to find biomarkers indicating the presence of life.
30.4 The Search for Extraterrestrial Intelligence
Some astronomers are engaged in the search for extraterrestrial intelligent life (SETI). Because other planetary systems are so far away, traveling to the stars is either very slow or extremely expensive (in terms of energy required). Despite many UFO reports and tremendous media publicity, there is no evidence that any of these are related to extraterrestrial visits. Scientists have determined that the best way to communicate with any intelligent civilizations out there is by using electromagnetic waves, and radio waves seem best suited to the task. So far, they have only begun to comb the many different possible stars, frequencies, signal types, and other factors that make up what we call the cosmic haystack problem. Some astronomers are also undertaking searches for brief, bright pulses of visible light and infrared signatures of huge construction projects by advanced civilizations. If we do find a signal someday, deciding whether to answer and what to answer may be two of the greatest challenges humanity will face.


29.2: The Age of the Universe
By the end of this section, you will be able to:
- Describe how we estimate the age of the universe
- Explain how changes in the rate of expansion over time affect estimates of the age of the universe
- Describe the evidence that dark energy exists and that the rate of expansion is currently accelerating
- Describe some independent evidence for the age of the universe that is consistent with the age estimate based on the rate of expansion
To explore the history of the universe, we will follow the same path that astronomers followed historically—beginning with studies of the nearby universe and then probing ever-more-distant objects and looking further back in time.
The realization that the universe changes with time came in the 1920s and 1930s when measurements of the redshifts of a large sample of galaxies became available. With hindsight, it is surprising that scientists were so shocked to discover that the universe is expanding. In fact, our theories of gravity demand that the universe must be either expanding or contracting. To show what we mean, let’s begin with a universe of finite size—say a giant ball of a thousand galaxies. All these galaxies attract each other because of their gravity. If they were initially stationary, they would inevitably begin to move closer together and eventually collide. They could avoid this collapse only if for some reason they happened to be moving away from each other at high speeds. In just the same way, only if a rocket is launched at high enough speed can it avoid falling back to Earth.
The problem of what happens in an infinite universe is harder to solve, but Einstein (and others) used his theory of general relativity (which we described in Black Holes and Curved Spacetime) to show that even infinite universes cannot be static. Since astronomers at that time did not yet know the universe was expanding (and Einstein himself was philosophically unwilling to accept a universe in motion), he changed his equations by introducing an arbitrary new term (we might call it a fudge factor) called the cosmological constant . This constant represented a hypothetical force of repulsion that could balance gravitational attraction on the largest scales and permit galaxies to remain at fixed distances from one another. That way, the universe could remain still.
About a decade later, Hubble, and his coworkers reported that the universe is expanding, so that no mysterious balancing force is needed. (We discussed this in the chapter on Galaxies.) Einstein is reported to have said that the introduction of the cosmological constant was “the biggest blunder of my life.” As we shall see later in this chapter, however, relatively recent observations indicate that the expansion is accelerating . Observations are now being carried out to determine whether this acceleration is consistent with a cosmological constant. In a way, it may turn out that Einstein was right after all.
View this web exhibit on the history of our thinking about cosmology, with images and biographies, from the American Institute of Physics Center for the History of Physics.
The Hubble Time
If we had a movie of the expanding universe and ran the film backward , what would we see? The galaxies, instead of moving apart, would move together in our movie—getting closer and closer all the time. Eventually, we would find that all the matter we can see today was once concentrated in an infinitesimally small volume. Astronomers identify this time with the beginning of the universe . The explosion of that concentrated universe at the beginning of time is called the Big Bang (not a bad term, since you can’t have a bigger bang than one that creates the entire universe). But when did this bang occur?
We can make a reasonable estimate of the time since the universal expansion began. To see how astronomers do this, let’s begin with an analogy. Suppose your astronomy class decides to have a party (a kind of “Big Bang”) at someone’s home to celebrate the end of the semester. Unfortunately, everyone is celebrating with so much enthusiasm that the neighbors call the police, who arrive and send everyone away at the same moment. You get home at 2 a.m., still somewhat upset about the way the party ended, and realize you forgot to look at your watch to see what time the police got there. But you use a map to measure that the distance between the party and your house is 40 kilometers. And you also remember that you drove the whole trip at a steady speed of 80 kilometers/hour (since you were worried about the police cars following you). Therefore, the trip must have taken:
So the party must have broken up at 1:30 a.m.
No humans were around to look at their watches when the universe began, but we can use the same technique to estimate when the galaxies began moving away from each other. (Remember that, in reality, it is space that is expanding, not the galaxies that are moving through static space.) If we can measure how far apart the galaxies are now, and how fast they are moving, we can figure out how long a trip it’s been.
Let’s call the age of the universe measured in this way T 0 . Let’s first do a simple case by assuming that the expansion has been at a constant rate ever since the expansion of the universe began. In this case, the time it has taken a galaxy to move a distance, d , away from the Milky Way (remember that at the beginning the galaxies were all together in a very tiny volume) is (as in our example)
where v is the velocity of the galaxy. If we can measure the speed with which galaxies are moving away, and also the distances between them, we can establish how long ago the expansion began.
Making such measurements should sound very familiar. This is just what Hubble and many astronomers after him needed to do in order to establish the Hubble law and the Hubble constant . We learned in Galaxies that a galaxy’s distance and its velocity in the expanding universe are related by
where H is the Hubble constant. Combining these two expressions gives us
We see, then, that the work of calculating this time was already done for us when astronomers measured the Hubble constant. The age of the universe estimated in this way turns out to be just the reciprocal of the Hubble constant (that is, 1/ H ). This age estimate is sometimes called the Hubble time . For a Hubble constant of 20 kilometers/second per million light-years, the Hubble time is about 15 billion years. (By the way, the unit used by astronomers for the Hubble constant is kilometers/second per million parsecs. In these units, the Hubble constant is equal to about 70 kilometers/second per million parsecs, again with an uncertainty of about 5%.)
To make numbers easier to remember, we have done some rounding here. Estimates for the Hubble constant are actually closer to 21 or 22 kilometers/second per million light-years, which would make the age closer to 14 billion years. But there is still about a 5% uncertainty in the Hubble constant, which means the age of the universe estimated in this way is also uncertain by about 5%.
To put these uncertainties in perspective, however, you should know that 50 years ago, the uncertainty was a factor of 2. Remarkable progress toward pinning down the Hubble constant has been made in the last couple of decades.
The Role of Deceleration
The Hubble time is the right age for the universe only if the expansion rate has been constant throughout the time since the expansion of the universe began. Continuing with our end-of-the-semester-party analogy, this is equivalent to assuming that you traveled home from the party at a constant rate, when in fact this may not have been the case. At first, mad about having to leave, you may have driven fast, but then as you calmed down—and thought about police cars on the highway—you may have begun to slow down until you were driving at a more socially acceptable speed (such as 80 kilometers/hour). In this case, given that you were driving faster at the beginning, the trip home would have taken less than a half-hour.
In the same way, in calculating the Hubble time, we have assumed that the expansion rate has been constant throughout all of time. It turns out that this is not a good assumption. Earlier in their thinking about this, astronomers expected that the rate of expansion should be slowing down. We know that matter creates gravity, whereby all objects pull on all other objects. The mutual attraction between galaxies was expected to slow the expansion as time passed. This means that, if gravity were the only force acting (a big if , as we shall see in the next section), then the rate of expansion must have been faster in the past than it is today. In this case, we would say the universe has been decelerating since the beginning.
How much it has decelerated depends on the importance of gravity in slowing the expansion. If the universe were nearly empty, the role of gravity would be minor. Then the deceleration would be close to zero, and the universe would have been expanding at a constant rate. But in a universe with any significant density of matter, the pull of gravity means that the rate of expansion should be slower now than it used to be. If we use the current rate of expansion to estimate how long it took the galaxies to reach their current separations, we will overestimate the age of the universe—just as we may have overestimated the time it took for you to get home from the party.
A Universal Acceleration
Astronomers spent several decades looking for evidence that the expansion was decelerating, but they were not successful. What they needed were 1) larger telescopes so that they could measure the redshifts of more distant galaxies and 2) a very luminous standard bulb (or standard candle), that is, some astronomical object with known luminosity that produces an enormous amount of energy and can be observed at distances of a billion light-years or more.
Recall that we discussed standard bulb s in the chapter on Galaxies. If we compare how luminous a standard bulb is supposed to be and how dim it actually looks in our telescopes, the difference allows us to calculate its distance. The redshift of the galaxy such a bulb is in can tell us how fast it is moving in the universe. So we can measure its distance and motion independently.
These two requirements were finally met in the 1990s. Astronomers showed that supernovae of type Ia (see The Death of Stars), with some corrections based on the shapes of their light curves, are standard bulbs. This type of supernova occurs when a white dwarf accretes enough material from a companion star to exceed the Chandrasekhar limit and then collapses and explodes. At the time of maximum brightness, these dramatic supernovae can briefly outshine the galaxies that host them, and hence, they can be observed at very large distances. Large 8- to 10-meter telescopes can be used to obtain the spectra needed to measure the redshifts of the host galaxies (Figure 29.3).
The result of painstaking, careful study of these supernovae in a range of galaxies, carried out by two groups of researchers, was published in 1998. It was shocking—and so revolutionary that their discovery received the 2011 Nobel Prize in Physics. What the researchers found was that these type Ia supernovae in distant galaxies were fainter than expected from Hubble’s law, given the measured redshifts of their host galaxies. In other words, distances estimated from the supernovae used as standard bulbs disagreed with the distances measured from the redshifts.
If the universe were decelerating, we would expect the far-away supernovae to be brighter than expected. The slowing down would have kept them closer to us. Instead, they were fainter , which at first seemed to make no sense.
Before accepting this shocking development, astronomers first explored the possibility that the supernovae might not really be as useful as standard bulbs as they thought. Perhaps the supernovae appeared too faint because dust along our line of sight to them absorbed some of their light. Or perhaps the supernovae at large distances were for some reason intrinsically less luminous than nearby supernovae of type Ia.
A host of more detailed observations ruled out these possibilities. Scientists then had to consider the alternative that the distance estimated from the redshift was incorrect. Distances derived from redshifts assume that the Hubble constant has been truly constant for all time. We saw that one way it might not be constant is that the expansion is slowing down. But suppose neither assumption is right (steady speed or slowing down.)
Suppose, instead, that the universe is accelerating . If the universe is expanding faster now than it was billions of years ago, our motion away from the distant supernovae has sped up since the explosion occurred, sweeping us farther away from them. The light of the explosion has to travel a greater distance to reach us than if the expansion rate were constant. The farther the light travels, the fainter it appears. This conclusion would explain the supernova observations in a natural way, and this has now been substantiated by many additional observations over the last couple of decades. It really seems that the expansion of the universe is accelerating , a notion so unexpected that astronomers at first resisted considering it.
How can the expansion of the universe be speeding up? If you want to accelerate your car, you must supply energy by stepping on the gas. Similarly, energy must be supplied to accelerate the expansion of the universe. The discovery of the acceleration was shocking because scientists still have no idea what the source of the energy is. Scientists call whatever it is dark energy , which is a clear sign of how little we understand it.
Note that this new component of the universe is not the dark matter we talked about in earlier chapters. Dark energy is something else that we have also not yet detected in our laboratories on Earth.
What is dark energy? One possibility is that it is the cosmological constant, which is an energy associated with the vacuum of “empty” space itself. Quantum mechanics (the intriguing theory of how things behave at the atomic and subatomic levels) tells us that the source of this vacuum energy might be tiny elementary particles that flicker in and out of existence everywhere throughout the universe. Various attempts have been made to calculate how big the effects of this vacuum energy should be, but so far these attempts have been unsuccessful. In fact, the order of magnitude of theoretical estimates of the vacuum energy based on the quantum mechanics of matter and the value required to account for the acceleration of the expansion of the universe differ by an incredible factor of at least 10 120 (that is a 1 followed by 120 zeros)! Various other theories have been suggested, but the bottom line is that, although there is compelling evidence that dark energy exists, we do not yet know the source of that energy.
Whatever the dark energy turns out to be, we should note that the discovery that the rate of expansion has not been constant since the beginning of the universe complicates the calculation of the age of the universe. Interestingly, the acceleration seems not to have started with the Big Bang. During the first several billion years after the Big Bang, when galaxies were close together, gravity was strong enough to slow the expansion. As galaxies moved farther apart, the effect of gravity weakened. Several billion years after the Big Bang, dark energy took over, and the expansion began to accelerate (Figure 29.4).
Deceleration works to make the age of the universe estimated by the simple relation seem older than it really is, whereas acceleration works to make it seem younger. By happy coincidence, our best estimates of how much deceleration and acceleration occurred lead to an answer for the age very close to . The best current estimate is that the universe is 13.8 billion years old with an uncertainty of only about 100 million years.
Throughout this chapter, we have referred to the Hubble constant . We now know that the Hubble constant does change with time. It is, however, constant everywhere in the universe at any given time. When we say the Hubble constant is about 70 kilometers/second/million parsecs, we mean that this is the value of the Hubble constant at the current time.
Comparing Ages
We now have one estimate for the age of the universe from its expansion. Is this estimate consistent with other observations? For example, are the oldest stars or other astronomical objects younger than 13.8 billion years? After all, the universe has to be at least as old as the oldest objects in it.
In our Galaxy and others, the oldest stars are found in the globular clusters (Figure 29.5), which can be dated using the models of stellar evolution described in the chapter Stars from Adolescence to Old Age.
The accuracy of the age estimates of the globular clusters has improved markedly in recent years for two reasons. First, models of interiors of globular cluster stars have been improved, mainly through better information about how atoms absorb radiation as they make their way from the center of a star out into space. Second, observations from satellites have improved the accuracy of our measurements of the distances to these clusters. The conclusion is that the oldest stars formed about 12–13 billion years ago.
This age estimate has recently been confirmed by the study of the spectrum of uranium in the stars. The isotope uranium-238 is radioactive and decays (changes into another element) over time. (Uranium-238 gets its designation because it has 92 protons and 146 neutrons.) We know (from how stars and supernovae make elements) how much uranium-238 is generally made compared to other elements. Suppose we measure the amount of uranium relative to nonradioactive elements in a very old star and in our own Sun, and compare the abundances. With those pieces of information, we can estimate how much longer the uranium has been decaying in the very old star because we know from our own Sun how much uranium decays in 4.5 billion years.
The line of uranium is very weak and hard to make out even in the Sun, but it has now been measured in one extremely old star using the European Very Large Telescope (Figure 29.6). Comparing the abundance with that in the solar system, whose age we know, astronomers estimate the star is 12.5 billion years old, with an uncertainty of about 3 billion years. While the uncertainty is large, this work is important confirmation of the ages estimated by studies of the globular cluster stars. Note that the uranium age estimate is completely independent; it does not depend on either the measurement of distances or on models of the interiors of stars.
As we shall see later in this chapter, the globular cluster stars probably did not form until the expansion of the universe had been underway for at least a few hundred million years. Accordingly, their ages are consistent with the 13.8 billion-year age estimated from the expansion rate.


10.3: The Continuity Correction
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Okay, time for a little bit of a digression.  There’s a tiny change that you need to make to your calculations whenever you only have 1 degree of freedom. It’s called the “continuity correction”, or sometimes the Yates correction . Remember what I pointed out earlier: the χ2 test is based on an approximation, specifically on the assumption that binomial distribution starts to look like a normal distribution for large N. One problem with this is that it often doesn’t quite work, especially when you’ve only got 1 degree of freedom (e.g., when you’re doing a test of independence on a 2×2 contingency table). The main reason for this is that the true sampling distribution for the X 2 statistic is actually discrete (because you’re dealing with categorical data!) but the χ2 distribution is continuous. This can introduce systematic problems.  Yates (1934) suggested a simple fix, in which you redefine the goodness of fit statistic as:
\(X^{2}=\sum_{i} \dfrac{\left(\left|E_{i}-O_{i}\right|-0.5\right)^{2}}{E_{i}}\)
Basically, he just subtracts off 0.5 everywhere. As far as I can tell from reading Yates’ paper, the correction is basically a hack. It’s not derived from any principled theory: rather, it’s based on an examination of the behaviour of the test, and observing that the corrected version seems to work better. I feel obliged to explain this because you will sometimes see R (or any other software for that matter) introduce this correction, so it’s kind of useful to know what they’re about. You’ll know when it happens, because the R output will explicitly say that it has used a “continuity correction” or “Yates’ correction”.


15.9C: Viral Gastroenteritis
- Recognize the viruses that cause gastroenteritis and their mode of transmission
Gastroenteritis is a medical condition characterized by inflammation (“-itis”) of the gastrointestinal tract that involves both the stomach (“gastro”-) and the small intestine (“entero”-), resulting in some combination of diarrhea, vomiting, abdominal pain and cramping. Gastroenteritis has also been referred to as gastro, stomach bug, and stomach virus. Although unrelated to influenza, it has also been called stomach flu and gastric flu.
Viruses that are known to cause gastroenteritis include rotavirus, norovirus, adenovirus, and astrovirus. Globally, Rotavirus is the most common cause of gastroenteritis in children, and produces similar incidence rates in both the developed and developing world. In adults, norovirus and Campylobacter are more common causes.
Viruses cause about 70% of episodes of infectious diarrhea in the pediatric age group. Rotavirus is a genus of double-stranded RNA virus in the family Reoviridae. Reoviruses are non-enveloped and have an icosahedral capsid composed of an outer and inner protein shell. The genomes of viruses in Reoviridae contains 10-12 segments which are grouped into three categories corresponding to their size: L (large), M (medium) and S (small). Segments range from ~ 3.9 kbp – 1kbp and each segment encodes 1-3 proteins. Since these viruses have dsRNA genomes, replication occurs exclusively in the cytoplasm and the virus encodes several proteins which are needed for replication.
The virus can enter the host cell via a receptor on the cell surface. The receptor is not known. After binding to the receptor the outer shell is partially digested to allow cell entry. The inner shell particle then enters the cytoplasm by a yet unknown process to start replication. Viral particles begin to assemble in the cytoplasm 6–7 hours after infection.
Rotavirus is a less common cause in adults due to their acquired immunity. Norovirus is the leading cause of gastroenteritis among adults in America, causing greater than 90% of outbreaks. Noroviruses contain an RNA genome of approximately 7.5 kbp, encoding a major structural protein (VP1) and a minor capsid protein (VP2). The virus particles demonstrate an amorphous surface structure when visualized using electron microscopy and are between 27-38 nm in size.
The most variable region between different viruses of the same type is a portion of the viral capsid. Specifically a region which contains antigen-presenting sites and carbohydrate-receptor binding regions, which is probably the region of the virus that binds to target cells. The estimated mutation rate (1.21 x 10 -2 to 1.41 x 10 -2 substitutions per site per year) in this virus is high, even compared with other RNA viruses. Norovirus epidemics typically occur when groups of people spend time in close physical proximity to each other, such as on cruise ships, in hospitals, or in restaurants. People may remain infectious even after their diarrhea has ended. Norovirus is the cause of about 10% of cases in children.
The foundation of management of gastroenteritis, viral-caused or otherwise, is adequate hydration. For mild or moderate cases, this can be typically achieved via oral rehydration solution. For more severe cases, intravenous fluids may be needed. Gastroenteritis primarily affects children and those in the developing world.
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Key Points
- Rotaviruses typically causes gastroenteritis in children. These are double-stranded viruses, which have two coats or capsids.
- Noroviruses, which cause most adult cases of gastroenteritis, are fast mutating viruses.
- The key to the treatment of gastroenteritis is rehydration, either orally or, in severe cases, intravenously.
Key Terms
- replication : Process by which an object, person, place or idea may be copied mimicked or reproduced.
- kbp : kilobase pair
- substitutions per site per year : A DNA mutation where one DNA base pair is replaced with another; often used synonymous with the term mutation rate.


5.1: Introduction
Oxygen is essential for sustaining life. The cardiovascular and the respiratory systems are responsible for supplying the body’s oxygen demands. Blood is oxygenated through the mechanisms of ventilation, perfusion, and the transport of respiratory gases (Potter, Perry, Ross-Kerr, & Wood, 2010).
Respiration is optimal when sufficient oxygenation occurs at the cellular level and when cellular waste and carbon dioxide are adequately removed via the bloodstream and lungs. If this system is interrupted — for example by lung tissue damage, inflammation or excess mucus in the airways, or impairment of ventilation — intervention is required to support the client and prevent the condition from worsening or, potentially, to prevent death from occurring (Perry, Potter, & Ostendorf, 2014).
Oxygen is the most frequently used medication in emergency medicine, and when used appropriately in the treatment of hypoxemia (an inadequate supply of oxygen in the arterial blood), it potentially saves lives (Kane, Decalmer, & O’Driscoll, 2013). This chapter describes the principles of oxygen therapy, the causes and management of hypoxia (the reduction of oxygen supply at the tissue level), and the optimal use of oxygen therapy and treatment modalities.
Learning Objectives
- Describe the principles of oxygenation
- Understand the functions and limitations of pulse oximetry
- Describe the causes of hypoxia
- Identify when oxygen therapy is needed
- Describe the management of hypoxia
- List hazards, precautions, and complications of oxygen therapy
- Describe how to perform oral suctioning


2.1: Introduction to the Cellular Level of Organization
Chapter Learning Objectives
After studying this chapter, you will be able to:
- Describe the structure and function of the cell membrane, including its regulation of materials into and out of the cell
- Describe the functions of the various cytoplasmic organelles
- Explain the structure and contents of the nucleus
- List the stages of the cell cycle in order, including the steps of cell division in somatic cells
- Discuss how a cell differentiates and becomes more specialized
You developed from a single fertilized egg cell into the complex organism containing trillions of cells that you see when you look in a mirror. During this developmental process, early, undifferentiated cells differentiate and become specialized in their structure and function. These different cell types form specialized tissues that work in concert to perform all of the functions necessary for the living organism. Cellular and developmental biologists study how the continued division of a single cell leads to such complexity and diversity in form and function.
Consider the difference between a structural cell in the skin and a nerve cell. A structural skin cell may be shaped like a flat plate (squamous) and live only for a short time before it is shed and replaced. Packed tightly into rows and sheets, the squamous skin cells provide a protective barrier for the cells and tissues that lie beneath. A nerve cell, on the other hand, may be shaped something like a star, sending out long processes up to a meter in length and may live for the entire lifetime of the organism. With their long winding appendages, nerve cells can communicate with one another and with other types of body cells and send rapid signals that inform the organism about its environment and allow it to interact with that environment. These differences illustrate one very important theme that is consistent at all organizational levels of biology: the form of a structure is optimally suited to perform particular functions assigned to that structure. Keep this theme in mind as you tour the inside of a cell and are introduced to the various types of cells in the body.
In spite of their diversity, a primary responsibility of every cell is to contribute to homeostasis. Homeostasis is a term used in biology that refers to a dynamic state of balance within parameters that are compatible with life. For example, living cells require a water-based environment to survive in, and there are various physical (anatomical) and physiological mechanisms that keep all of the trillions of living cells in the human body moist. This is one aspect of homeostasis. When a particular parameter, such as blood pressure or blood oxygen content, moves far enough out of homeostasis (generally becoming too high or too low), illness or disease—and sometimes death—inevitably results.
Contributors and Attributions
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OpenStax Anatomy & Physiology (CC BY 4.0). Access for free at https://openstax.org/books/anatomy-and-physiology


14.7: Coping with the Dangers of Rampant Transposition
Most organisms do not have the high transposon load that we have. For those like us, and given a general tendency of transposons to insert at random into new DNA loci, how come we exist at all? Isn’t the danger of transposition into essential gene sequences magnified by the possibility of multiple simultaneous transpositions of elements generated by cut-and-paste and especially replicative mechanisms? Indeed, transposons have been found in genes that are inactive as a result.
An obvious explanation for our survival of transposon activity is that most transposition is into the >90% percent of the genome that does not code for proteins. Another is that eukaryotic organisms have two copies of every gene, so that if one is inactive, the other may sustain us. Beyond this, several mechanisms exist to silence a transposon after transposition has occurred, mitigating the dangers of rampant transposition. As long as a transposition is not lethal (e.g., because its integration disrupts an activity essential to life), the cell and organisms can survive the event. In time, mutations at the ends of CMB3e 344 transposons or in genes responsible for transposition would render them inactive. Finally, there may be a more direct curb on transposition. The s mall interfering RNAs ( siRNAs ) we encountered earlier could complement and target viral RNAs for destruction (see the Transcription chapter for more information on siRNAs ). There is some evidence that siRNAs similarly target transposon transcripts.
Summing up, transposon activity is moderated by mutational loss of function and/or by more direct mechanisms that limit transposition and thus genetic damage. If an accumulation of transposons to a high load, as occurs in many species, were deleterious, they would be limited or eliminated from genomes. Instead, persistent transposons and acts of transposition are largely neutral, increasing options for diversity in the selection of new genotypes and phenotypic characteristics. We also know now that transposons can function in genetic regulation. Thus, transposons are neither selfish nor junk DNA. Check out these links for more: Not junk after all? and Eulogy for Junk DNA .


12.23: Reading- The Role of Intermediaries
Introduction
While the retail channel is most familiar to students, wholesalers play an important role as intermediaries. Intermediaries act as a link in the distribution process, but the roles they fill are broader than simply connecting the different channel partners. Wholesalers, often called “merchant wholesalers,” help move goods between producers and retailers.
For example, McLane Company Inc. is among the largest wholesalers in the United States. The breadth of its operations is described on the company Web site:
McLane Foodservice and wholly owned subsidiary, Meadowbrook Meat Company, Inc., operates 80 distribution centers across the U.S. and one of the nation’s largest private fleets. The company buys, sells, and delivers more than 50,000 different consumer products to nearly 90,000 locations across the U.S. In addition, McLane provides alcoholic beverage distribution through its wholly owned subsidiary, Empire Distributors, Inc. McLane is a wholly owned unit of Berkshire Hathaway Inc. and employs more than 20,000 teammates. [1]
Let’s look at each of the functions that a merchant wholesaler fulfills.
Purchasing
Wholesalers purchase very large quantities of goods directly from producers or from other wholesalers. By purchasing large quantities or volumes, wholesalers are able to secure significantly lower prices.
Imagine a situation in which a farmer grows a very large crop of potatoes. If he sells all of the potatoes to a single wholesaler, he will negotiate one price and make one sale. Because this is an efficient process that allows him to focus on farming (rather than searching for additional buyers), he will likely be willing to negotiate a lower price. Even more important, because the wholesaler has such strong buying power, the wholesaler is able to force a lower price on every farmer who is selling potatoes.
The same is true for almost all mass-produced goods. When a producer creates a large quantity of goods, it is most efficient to sell all of them to one wholesaler, rather than negotiating prices and making sales with many retailers or an even larger number of consumers. Also, the bigger the wholesaler is, the more likely it will have significant power to set attractive prices.
Warehousing and Transportation
Once the wholesaler has purchased a mass quantity of goods, it needs to get them to a place where they can be purchased by consumers. This is a complex and expensive process. McLane Company operates eighty distribution centers around the country. Its distribution center in Northfield, Missouri, is 560,000 square feet big and is outfitted with a state-of-the art inventory tracking system that allows it to manage the diverse products that move through the center. [2] It relies on its own vast trucking fleet to handle the transportation.
Grading and Packaging
Wholesalers buy a very large quantity of goods and then break that quantity down into smaller lots. The process of breaking large quantities into smaller lots that will be resold is called bulk breaking. Often this includes physically sorting, grading, and assembling the goods. Returning to our potato example, the wholesaler would determine which potatoes are of a size and quality to sell individually and which are to be packaged for sale in five-pound bags. [3]
Risk Bearing
Wholesalers either take title to the goods they purchase, or they own the goods they purchase. There are two primary consequences of this, both of which are both very important to the distribution channel. First, it means that the wholesaler finances the purchase of the goods and carries the cost of the goods in inventory until they are sold. Because this is a tremendous expense, it drives wholesalers to be accurate and efficient in their purchasing, warehousing, and transportation processes.
Second, wholesalers also bear the risk for the products until they are delivered. If goods are damaged in transport and cannot be sold, then the wholesaler is left with the goods and the cost. If there is a significant change in the value of the products between the time of the purchase from the producer and the sale to the retailer, the wholesaler will absorb that profit or loss.
Marketing
Often, the wholesaler will fill a role in the promotion of the products that it distributes. This might include creating displays for the wholesaler’s products and providing the display to retailers to increase sales. The wholesaler may advertise its products that are carried by many retailers.
Wholesalers also influence which products the retailer offers. For example, McLane Company was a winner of the 2016 Convenience Store News Category Captains, in recognition for its innovations in providing the right products to its customers. McLane created unique packaging and products featuring movie themes, college football themes, and other special occasion branding that were designed to appeal to impulse buyers. They also shifted the transportation and delivery strategy to get the right products in front of consumers at the time they were most likely to buy. Its convenience store customers are seeing sales growth, as is the wholesaler. [4]
Distribution
As distribution channels have evolved, some retailers, such as Walmart and Target, have grown so large that they have taken over aspects of the wholesale function. Still, it is unlikely that wholesalers will ever go away. Most retailers rely on wholesalers to fulfill the functions that we have discussed, and they simply do not have the capability or expertise to manage the full distribution process. Plus, many of the functions that wholesalers fill are performed most efficiently at scale. Wholesalers are able to focus on creating efficiencies for their retail channel partners that are very difficult to replicate on a small scale.
- www.mclaneco.com/content/mclane/en/about-us.html ↵
- www.mclaneco.com/content/mclane/en/solutions/grocery-supply-chain-solutions/locations/mclane-minnesota.html ↵
- unstats.un.org/unsd/cr/registry/regcs.asp?Cl=9&Lg=1&Co=6 ↵
- http://www.csnews.com/industry-news-and-trends/special-features/why-mclane-2016s-general-merchandise-category-captain?nopaging=1 ↵
Contributors and Attributions
- Provided by : Lumen Learning. License : CC BY: Attribution
- Potatoes. Authored by : Olivier Bacquet. Located at : https://www.flickr.com/photos/olibac/10508674534/ . License : CC BY: Attribution