33.2: Economic Crises
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Causes and Immediate Impacts of the Crisis
Banks, consumers, and the government all contributed to improper borrowing and lending, which in turn created a downward spiraling economy.
learning objectives
- Summarize the causes that led to the 2007 banking crisis
The recent financial crisis, commonly referred to as the sub-prime mortgage crisis of 2007-2008, was borne of the failure of a series of derivative-based consolidation of mortgage-backed securities that encapsulated extremely high risk loans to homeowners into a falsely ‘safe’ investment. To simplify this, banks pushed mortgages on prospective homeowners who could not afford to repay them. Then they combined and packaged varying mortgage-backed securities based off of these loans and sold them as highly dependable and safe investments, either through a lack of due diligence (negligence) or lack of ethical consideration. This created an economic meltdown, starting with the United States, that spread across the global markets.
The inherent complexity of the causes and dramatic repercussions (most of which are still ongoing) require a great deal of context. It is a fiercely debated and widely discussed issue in the field of economics (and in mainstream media), providing a real-life case study for many of the critical concepts of economic theory.
How Did This Happen?
The inputs to the 2007-2008 economic collapse, briefly touched upon above, are complex and still evolving. That being said, there are a few key talking points from an economic perspective that should be discussed. A useful perspective to take is the various stakeholders and their contributions:
Inputs to the Mortgage Crisis : This graph outlines two of the three parties in the collapse (excludes government), as the banks and the buyers both took on ridiculous amounts of risk.
- Banks: Simply put, the banks made two critical errors. First, they lent money to people who could not pay it back (to buy homes). They pursued what is referred to as ‘predatory lending,’ or lending to individuals they knew could never pay it back. Secondly, banks knowingly grouped these loans into bundles called collateralized debt obligations (CDOs) and sold them as extremely safe derivative investments. They were not safe.
- Consumers: Consumers played their role as well, acting as easy prey for the banks predatory practices. Individuals bought homes they could not afford utilizing loans they could not pay back. This drove them into debt, to the extent at which they had to default. This meant that the capital banks expected to get back did not arrive, it simply was not there.
- Government: The government did not regulate the housing market, as a result of the elimination of two critical legal clauses that required the verification of income and a 20% down payment. In short, the U.S. government used to ensure that prospective home buyers could put down 20% of the their borrowing in addition to verify that their income could cover their mortgage payments. Without such verification, it became easier for people to get mortgages they could not afford.
Combining these factors, the problem largely revolved around irresponsible lending and borrowing which was then turned into derivatives that were labeled safe despite their massive risks. This resulted in an economic realization of loans that could not be repaid, which spread through the banking system and turned into large scale obligations that could not be met.
Economic Impact
What happened next is well captured in the diagram below. In short, the banks eventually failed due to their investments. In order to prevent the entire financial system from collapsing, some of the banks (and other financial institutions) were bailed out.
2008 Crisis Flow Chart : This chart embodies critical checkpoints in the economic decline reactions to poor mortgage management by the banks. Understanding the implications of each point on this diagram will greatly enhance the larger understanding of the short term effects of this economic collapse.
Of course the negative effects did not stop there. The U.S. stock market lost confidence in financial institutions and some of the companies connected to them and subsequently crashed. The NYSE fell by half, drastically reducing the value of the U.S. economy. This was then telegraphed into a loss of consumer confidence and business access to investment. Within a few months, there were job cuts, bankruptcies, and reduced spending, as the crisis spread throughout the economy (both domestically and globally).
Recovery
The objective of economic recovery when in crisis is to stabilize the economy and recapture the value lost using economic stimulus strategies.
learning objectives
- Discuss the characteristics of the recovery from the 2007 crisis
The 2007-2009 economic crisis has had far-reaching and profound effects on both the domestic and global markets, primarily as a result of the sub-prime mortgage disaster originating in the United States. Addressing these economic ramifications to induce recovery has been the focal point of global governments and global agencies such as the International Monetary Fund (IMF). The objective of economic recovery when in crisis is to stabilize the economy, and from there recapture the value lost through economic stimulus strategies while addressing the factors which contributed to the collapse in the first place.
Stimulus Package
One of the key components to the crisis recover in the United States is an act called the American Recovery and Reinvestment Act of 2009 (ARRA), put into place by the Obama administration just as the first days of his term were beginning. This act has seen substantial debate, both positively and negatively, as to the efficacy and overall implementation of the program. Understanding the inputs, and expected outcomes, is critical to understanding the economics behind reacting to economic crises (particularly from a Keynesian perspective).
The stimulus package can be broken down via the attached figure in regards to monetary investment in specific places, totaling $831 billion (USD) between 2009 and 2019. The goal of investing or providing tax relief and subsidies for individuals and companies is to drive up purchasing behavior and offset the positive feedback loop attributed to economic crises. This is largely based on the Keynesian concept of driving spending through enabling spending, in turn driving up demand, creating jobs, and driving spending up further. President Obama’s administration was criticized by classical economists for employing this as well as Keynesian economists (such as Paul Krugman) for not employing it enough. That being said, the efficacy in the attached figure demonstrates that it was likely a strategic reaction to the economic crisis.
ARRA Efficacy Projections : This graph points out the economic opportunity cost of not utilizing the ARRA, which would likely have left the U.S. (and subsequently, the global) economy in significantly worse shape than it is now.
Stimulus Investments (U.S.) of ARRA : This graphic demonstrates the different silos receiving government aid within the domestic economy, as a direct result of the American Recover and Reinvestment Act (ARRA).
Troubled Asset Relief Program (TARP)
Perhaps more debatable still, is the reaction to the inevitable and deserved bankruptcy of the banks and insurers involved in the toxic mortgage-backed securities (i.e. CDO’s) that drove the economy into disaster were bailed out by the government. These companies, such as AIG, Bank of America, Citigroup, and other distributors of toxic investments were handed the required capital by the government to offset their massive losses due to undue risk and poor leveraging. This was in the form of the government utilizing tax money to purchase these securities, removing the toxic assets from the books of the companies involved (who were deemed ‘too big to fail’). This move saved the economic decline and restored consumer confidence through direct government intervention.
TARP was also largely criticized, with a high number of seemingly reasonable objections. The first, and most intuitive, is that these businesses deserved to go under. Bad business practice, poor investment, and grossly unethical behavior deserves bankruptcy. Instead, the government demonstrated that, as long as certain fiscal influence is achieved, these competitive rules are negligible. Secondly, and slightly more complex, is the implementation of the TARP act (which necessitated SIG-TARP, an oversight group ensuring that TARP money went out to those who it was intended for). It was noted on many occasions that TARP money was ill-used.
Outcomes
While the long-term outcomes of these practices cannot yet be predicted, the progress made so far is worth analyzing economically. First and foremost, job numbers have improved, although not as much as had been hoped or expected (see ). While this is positive, it does not capture the large number of people who are underemployed or the individuals who have abandoned the search for employment. GDP growth has inched along to positive numbers, as has the profitability of many businesses and industries. Interestingly enough, as of the end of 2013, the stock market has not only recovered but expanded beyond 2007 levels.
U.S. Job Gains and Losses : This graph demonstrates the negative affect that the collapse had on jobs as well as the pacing of economic recovery in the short-term.
Global Impacts
The 2007-2009 economic collapse was damaging not only to the U.S. but also global markets, driving the global economy into recession.
learning objectives
- Analyze the extent to which the 2007 crisis was global
Modern markets are dependent upon one another across national borders, where global trends in economic growth and well-being will have a dramatic impact on national economic well-being and vice versa. As a result, the 2007-2009 economic collapse had large effects not only at the origin (in the United States), but also on a global scale. The speed in which the market decline spread across the globe underlines just how far globalization and international interdependence has come, with GDP growth numbers in 2009 already demonstrating substantial losses across the map (see ).
2009 Global GDP Growth and Decline) : As this map illustrates, many international markets fell rapidly into decline as a direct result of the U.S. sub-prime mortgage disaster.
Recession: Domestic to Global
In December 2007, the U.S. officially fell into an 18-month long recessionary period of negative GDP growth (over two consecutive quarters). This recessionary period spread rapidly around the map, creating a global recession in Q3 and Q4 in 2008 and Q1 of 2009 (defined as a contraction in global GDP growth during that time) as is represented in this figure. To provide additional context to the global adverse effects of the sub-prime mortgage crisis, of 65 countries that record and report GDP only 11 escaped a recessionary period between 2006 and today.
World GDP Growth : It is quite clear in this graphic, the global GDP growth dropped dramatically following the U.S. crisis, pitching the entire global economy into a recession.
Even countries where double-digit economic growth had been a consistent trend going into 2008, such as China, began to experience growth reductions due to reduced consumer purchasing power on a global scale. China has seen reductions towards the 7%-8% economic GDP growth (year on year), from clear double-digits in previous years.
Political Instability
Another indirect global impact that occurred as a result of the economic collapse is political instability, primarily due to the inability of developed nations to pursue social welfare investments and global poverty reduction processes during recessionary times. Indeed, these instabilities are not only isolated to developing nations. Countries in the EU, such as Greece, Spain and Italy, have seen dramatic GDP decreases and unemployment numbers reaching or exceeding 20% in some cases. This instability has placed a great deal of pressure on government officials to solve these huge economic problems in the short-term. The United States has also seen an incredible reduction in governmental efficacy with the least effective house of representatives for nearly a century alongside dramatic polarization of public opinion towards left-wing and right-wing ideas.
Global Responses
Positively, many global organizations and countries are actively employing policies to minimize the likelihood of a re-occurrence in the future. Reducing interest rates to drive up borrowing and investment, providing tax benefits to the unemployed and underemployed, and subsidizing new business have created positive steps towards meaningful recovery globally.
There have also been a series of banking and financial regulatory changes across the world.These global safety nets and prevention policies are setting the tone for future strategies to avoid economic crises and minimize the prospective damage that occurs as a result of these unethical practices.
Key Points
- The recent financial crisis, commonly referred to as the sub-prime mortgage crisis of 2007-2008, began with the failure of a series of derivative-based consolidation of mortgage-backed securities that encapsulated extremely high risk loans to home-owners into a falsely ‘safe’ investment.
- Banks offered loans to debtors that couldn’t afford them, and then bundles these debt instruments and sold them.
- The banking crisis spread into a broader financial crisis as companies were negatively affected by the crisis in financial institutions to which they were connected.
- The government did not regulate the housing market at all, as a result of the elimination of two critical clauses: verification of income and a 20% down payment.
- The U.S. stock market, realizing the scale of errors of the banks, lost all investment confidence. This cut the NYSE in half, drastically reducing the value of the U.S. economy.
- One of the key components to the crisis recovery in the United States is an act called the American Recovery and Reinvestment Act of 2009 (ARRA). It invests money in the economy to drive spending and recovery.
- ARRA is largely based on the Keynesian macro-environmental concept of driving spending through enabling spending, in turn driving up demand, creating jobs, and driving spending up further.
- The Troubled Asset Relief Program (TARP) was another recovery strategy, buying toxic assets off the banks to prevent them from failing.
- TARP was criticized for protecting banks who behaved unethically and with a lack of strategic intelligence as businesses, essentially implying that they should have failed.
- While the stock market has recovered and the banks are in better shape now than before the collapse, the average American is still less likely to have a job or to be underemployed.
- Modern markets are dependent upon one another across national borders, where global trends in economic growth and well-being will have a dramatic impact on national economic well-being and vice versa.
- In December 2007, the U.S. officially fell into an 18-month long recessionary period of negative GDP growth, which This spread rapidly around the map to create a global recession in Q3 and Q4 in 2008 and Q1 of 2009.
- Another indirect global impact that occurred as a result of the economic collapse was political instability, primarily due to the inability of developed nations to pursue altruistic investments and global poverty reduction processes during recessionary times.
- On the upside, many global organizations and countries are actively employing policies to minimize the likelihood of a re-occurrence in the future.
Key Terms
- CDO : A type of asset-backed security and structured credit product constructed from a portfolio of fixed-income assets.
- Sub-prime : Designating a loan (typically at a greater than usual rate of interest) offered to a borrower who is not qualified for other loans (e.g. because of poor credit history).
- stimulus : Anything that may have an impact or influence on a system. In 2009, it is the monetary investments in the economy to recover from the collapse.
- Economic crises : A period of economic slowdown characterized by declining productivity and devaluing of financial institutions often due to reckless and unsustainable money lending.
- recession : A significant decline in economic activity spread across the economy, lasting more than a few months, normally visible in real GDP, real income, employment, and industrial production.
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12.6: Hydration of Alkynes
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Objectives
After completing this section, you should be able to
- write the equation for the reaction of water with an alkyne in the presence of sulfuric acid and mercury(II) sulfate.
- describe keto-enol tautomerism.
- predict the structure of the ketone formed when a given alkyne reacts with sulfuric acid in the presence of mercury(II) sulfate.
- identify the reagents needed to convert a given alkyne to a given ketone.
- identify the alkyne needed to prepare a given ketone by hydration of the triple bond.
- write an equation for the reaction of an alkyne with borane.
- write the equation for the reaction of a vinylic borane with basic hydrogen peroxide or hot acetic acid.
- identify the reagents, the alkyne, or both, needed to prepare a given ketone or a given cis alkene through a vinylic borane intermediate.
- identify the ketone produced when a given alkyne is reacted with borane followed by basic hydrogen peroxide.
- identify the cis alkene produced when a given alkyne is reacted with borane followed by hot acetic acid.
- explain why it is necessary to use a bulky, sterically hindered borane when preparing vinylic boranes from terminal alkynes.
- predict the product formed when the vinylic borane produced from a terminal alkyne is treated with basic hydrogen peroxide.
- identify the alkyne needed to prepare a given aldehyde by a vinylic borane.
Key Terms
Make certain that you can define, and use in context, the key terms below.
- enol
- keto-enol tautomeric equilibrium
- tautomerism
- tautomers
Study Notes
Rapid interconversion between tautomers is called tautomerism ; however, as the two tautomers are in equilibrium, the term tautomeric equilibrium may be used. This section demonstrates the equilibrium between a ketone and an enol; hence, the term keto - enol tautomeric equilibrium is appropriate. The term “enol” indicates the presence of a carbon-carbon double bond and a hydroxyl (i.e., alcohol) group. Later in the course, you will see the importance of keto-enol tautomerism in discussions of the reactions of ketones, carbohydrates and nucleic acids.
It is important to note that tautomerism is not restricted to keto-enol systems. Other examples include imine-enamine tautomerism
and nitroso-oxime tautomerism
However, at the moment you need only concern yourself with keto-enol tautomerism.
Notice how hydroboration complements hydration in the chemistry of both alkenes and alkynes.
Mercury(II)-Catalyzed Hydration of Alkynes
As with alkenes, hydration (addition of water) of alkynes requires a strong acid, usually sulfuric acid, and is facilitated by the mercuric ion (Hg 2 + ). However, the hydration of alkynes gives ketone products while the hydration of alkenes gives alcohol products. Notice that the addition of oxygen in both reactions follows Markovnikov rule.
During the hydration of an alkyne, the initial product is an enol intermediate (a compound having a hydroxyl substituent attached to a double-bond), which immediately rearranges to the more stable ketone through a process called enol-keto tautomerization .
Tautomers are defined as rapidly inter-converted constitutional isomers, usually distinguished by a different bonding location for a labile hydrogen atom and a differently located double bond. The keto and enol tautomers are in equilibrium with each other and with few exceptions the keto tautomer is more thermodynamically stable and therefor favored by the equilibrium. This mechanism for tautomerization will be discussed in greater detail in Section 22-1 .
General Reaction
For terminal alkynes, the addition of water follows the Markovnikov rule, and the final product is a methyl ketone. For internal alkynes the addition of water is not regioselective. Hydration of symmetrical internal alkynes produces a single ketone product. However, hydration of asymmetrical alkynes, (i.e. if R & R' are not the same ) produces two isomeric ketone products.
Mechanism
The mechanism starts with the electrophilic addition of the mercuric ion (Hg 2 + ) to the alkyne producing a mercury-containing vinylic carbocation intermediate. Nucleophilic attack of water on the vinylic carbocation forms a C-O bond to produce a protonated enol. Deprotonation of the enol by water then produces a organomercury enol. The mercury is substituted with H + to produced a neutral enol and regenerate the Hg 2 + catalyst. The enol is converted to the ketone product through keto-enol tautomerization the mechanism of which is provided in Section 22-1 .
Step 1: Electrophilic addition of Hg 2 +
Step 2: Nucleophilic attack by water
Step 3: Deprotonation
Step 4: Substitution
Step 5: Tautomerization
Hydroboration–Oxidation of Alkynes
The hydroboration-oxidation of alkynes is analagous to the reaction with alkenes. However, where alkenes for alcohol products, alkynes for aldehyde or ketone products. In both cases the addition is anti-Markovnikov and an oxygen is placed on the less alkyl substituted carbon. With the hydroboration of an alkyne the presences of a second pi bond allows the initial product to under tautomerization to become the final aldehyde product.
Alkynes have two pi bonds both of which are capable of reacting with borane (BH 3 ). To limit the reactivity to only one alkyne pi bond, a dialkyl borane reagent (R 2 BH) is used. Replacing two of the hydrogens on the borane with alkyl groups also creates steric hindrance which enhances the anti-Markovnikov regioselective of the reaction. Disiamylborane (Sia 2 BH) and 9-borabicyclo[3.3.1]nonane (9-BBN) are two common reagents for this hydroboration reaction. The oxidation reagents (a basic hydrogen peroxide solution) are the same for both alkenes and alkynes.
General Reaction
The hydroboration of terminal alkynes produces aldehyde products while internal alkynes produce ketone products. The hydroboration of symmetrical alkynes produces one ketone product and asymmetrical alkynes produce a mixture of product ketones.
Mechanism
The mechanism starts with the electrophilic addition of the B-H bond of the borane. The hydrogen atom and the borane all on the same side of the alkyne creating a syn addition configuration in the alkene product. Also, the addition is anti-Markovnikov regioselective which means the borane adds to the less substituted carbon of the alkyne and the hydrogen atom adds to the more substituted. The oxidative work-up replaces the borane with a hydroxy group (-OH) creating an enol intermediate. The enol immediately tautomerizes to the product aldehyde for terminal alkynes and the product ketone for internal alkynes.
Comparison of Mercury(II)-Catalyzed Hydration and Hydroboration–Oxidation of Alkynes
These two reactions are complementary for the reaction of a terminal alkyne because the produce distinctly different products. The mercury(II) catalyzed hydration of a terminal alkyne produces a methyl ketone, while the hydroboration-oxidation produces an aldehyde.
For internal alkynes, the regioslectivity of these reactions are rendered ineffective. The reactions are redundant in that they both produce the same ketone products.
Exercise \(\PageIndex{1}\)
Draw the structure of the product formed when each of the substances below is treated with H 2 O/H 2 SO 4 in the presence of HgSO 4 .
a)
b)
- Answer
-
a)
b)
Exercise \(\PageIndex{2}\)
Draw the structure of the keto form of the compound shown below. Which form would you expect to be the most stable?
- Answer
-
The keto form should be the most stable.
Exercise \(\PageIndex{3}\)
What alkyne would you start with to gain the following products?
- Answer
-
Exercise \(\PageIndex{4}\)
What alkyne would you start with to gain the following product?
- Answer
-
Exercise \(\PageIndex{5}\)
Draw the product(s) of the following reactions:
- Answer
-
For internal alkynes, there is no difference in the reaction products.


3: Segmentation and Targeting Last updated Save as PDF Page ID 47854 Lumen Learning Lumen Learning 3.1: Case Study- eHarmony Targets Women 3.2: Self Check- Segmentation Decisions 3.3: Outcome- Targeting and Marketing Mix 3.4: Reading- Targeting Strategies and the Marketing Mix 3.5: Case Study- Red Bull Wins the “Extreme” Niche 3.6: Simulation- Segmenting the Ice Cream Market 3.7: Self Check- Targeting and Marketing Mix 3.8: Putting It Together- Segmentation and Targeting 3.9: Why It Matters- Segmentation and Targeting 3.10: Outcome- Segmentation and Targeting Rationale 3.11: Reading- The Purpose of Market Segmentation and Targeting 3.12: Self Check- Segmentation and Targeting Rationale 3.13: Outcome- Common Segmentation Approaches 3.14: Reading- Segmentation Criteria and Approaches 3.15: Self Check- Common Segmentation Approaches 3.16: Outcome- Segmentation Decisions 3.17: Reading- Choosing a Segmentation Approach and Target Segments 3.18: Case Study - eHarmony Targets Women


39.3: Breathing
Skills to Develop
- Describe how the structures of the lungs and thoracic cavity control the mechanics of breathing
- Explain the importance of compliance and resistance in the lungs
- Discuss problems that may arise due to a V/Q mismatch
Mammalian lungs are located in the thoracic cavity where they are surrounded and protected by the rib cage, intercostal muscles, and bound by the chest wall. The bottom of the lungs is contained by the diaphragm, a skeletal muscle that facilitates breathing. Breathing requires the coordination of the lungs, the chest wall, and most importantly, the diaphragm.
Types of Breathing
Amphibians have evolved multiple ways of breathing. Young amphibians, like tadpoles, use gills to breathe, and they don’t leave the water. Some amphibians retain gills for life. As the tadpole grows, the gills disappear and lungs grow. These lungs are primitive and not as evolved as mammalian lungs. Adult amphibians are lacking or have a reduced diaphragm, so breathing via lungs is forced. The other means of breathing for amphibians is diffusion across the skin. To aid this diffusion, amphibian skin must remain moist.
Birds face a unique challenge with respect to breathing: They fly. Flying consumes a great amount of energy; therefore, birds require a lot of oxygen to aid their metabolic processes. Birds have evolved a respiratory system that supplies them with the oxygen needed to enable flying. Similar to mammals, birds have lungs, which are organs specialized for gas exchange. Oxygenated air, taken in during inhalation, diffuses across the surface of the lungs into the bloodstream, and carbon dioxide diffuses from the blood into the lungs and expelled during exhalation. The details of breathing between birds and mammals differ substantially.
In addition to lungs, birds have air sacs inside their body. Air flows in one direction from the posterior air sacs to the lungs and out of the anterior air sacs. The flow of air is in the opposite direction from blood flow, and gas exchange takes place much more efficiently. This type of breathing enables birds to obtain the requisite oxygen, even at higher altitudes where the oxygen concentration is low. This directionality of airflow requires two cycles of air intake and exhalation to completely get the air out of the lungs.
Evolution Connection: Avian Respiration
Birds have evolved a respiratory system that enables them to fly. Flying is a high-energy process and requires a lot of oxygen. Furthermore, many birds fly in high altitudes where the concentration of oxygen in low. How did birds evolve a respiratory system that is so unique?
Decades of research by paleontologists have shown that birds evolved from therapods, meat-eating dinosaurs (Figure \(\PageIndex{1}\)). In fact, fossil evidence shows that meat-eating dinosaurs that lived more than 100 million years ago had a similar flow-through respiratory system with lungs and air sacs. Archaeopteryx and Xiaotingia , for example, were flying dinosaurs and are believed to be early precursors of birds.
Most of us consider that dinosaurs are extinct. However, modern birds are descendants of avian dinosaurs. The respiratory system of modern birds has been evolving for hundreds of millions of years.
All mammals have lungs that are the main organs for breathing. Lung capacity has evolved to support the animal’s activities. During inhalation, the lungs expand with air, and oxygen diffuses across the lung’s surface and enters the bloodstream. During exhalation, the lungs expel air and lung volume decreases. In the next few sections, the process of human breathing will be explained.
The Mechanics of Human Breathing
Boyle’s Law is the gas law that states that in a closed space, pressure and volume are inversely related. As volume decreases, pressure increases and vice versa (Figure \(\PageIndex{2}\)). The relationship between gas pressure and volume helps to explain the mechanics of breathing.
There is always a slightly negative pressure within the thoracic cavity, which aids in keeping the airways of the lungs open. During inhalation, volume increases as a result of contraction of the diaphragm, and pressure decreases (according to Boyle’s Law). This decrease of pressure in the thoracic cavity relative to the environment makes the cavity less than the atmosphere (Figure \(\PageIndex{3}\)a). Because of this drop in pressure, air rushes into the respiratory passages. To increase the volume of the lungs, the chest wall expands. This results from the contraction of the intercostal muscles , the muscles that are connected to the rib cage. Lung volume expands because the diaphragm contracts and the intercostals muscles contract, thus expanding the thoracic cavity. This increase in the volume of the thoracic cavity lowers pressure compared to the atmosphere, so air rushes into the lungs, thus increasing its volume. The resulting increase in volume is largely attributed to an increase in alveolar space, because the bronchioles and bronchi are stiff structures that do not change in size.
The chest wall expands out and away from the lungs. The lungs are elastic; therefore, when air fills the lungs, the elastic recoil within the tissues of the lung exerts pressure back toward the interior of the lungs. These outward and inward forces compete to inflate and deflate the lung with every breath. Upon exhalation, the lungs recoil to force the air out of the lungs, and the intercostal muscles relax, returning the chest wall back to its original position (Figure \(\PageIndex{3}\)b). The diaphragm also relaxes and moves higher into the thoracic cavity. This increases the pressure within the thoracic cavity relative to the environment, and air rushes out of the lungs. The movement of air out of the lungs is a passive event. No muscles are contracting to expel the air.
Each lung is surrounded by an invaginated sac. The layer of tissue that covers the lung and dips into spaces is called the visceral pleura . A second layer of parietal pleura lines the interior of the thorax (Figure \(\PageIndex{4}\)). The space between these layers, the intrapleural space , contains a small amount of fluid that protects the tissue and reduces the friction generated from rubbing the tissue layers together as the lungs contract and relax. Pleurisy results when these layers of tissue become inflamed; it is painful because the inflammation increases the pressure within the thoracic cavity and reduces the volume of the lung.
Link to Learning
View how Boyle’s Law is related to breathing and watch this video on Boyle’s Law.
The Work of Breathing
The number of breaths per minute is the respiratory rate . On average, under non-exertion conditions, the human respiratory rate is 12–15 breaths/minute. The respiratory rate contributes to the alveolar ventilation , or how much air moves into and out of the alveoli. Alveolar ventilation prevents carbon dioxide buildup in the alveoli. There are two ways to keep the alveolar ventilation constant: increase the respiratory rate while decreasing the tidal volume of air per breath (shallow breathing), or decrease the respiratory rate while increasing the tidal volume per breath. In either case, the ventilation remains the same, but the work done and type of work needed are quite different. Both tidal volume and respiratory rate are closely regulated when oxygen demand increases.
There are two types of work conducted during respiration, flow-resistive and elastic work. Flow-resistive refers to the work of the alveoli and tissues in the lung, whereas elastic work refers to the work of the intercostal muscles, chest wall, and diaphragm. Increasing the respiration rate increases the flow-resistive work of the airways and decreases the elastic work of the muscles. Decreasing the respiratory rate reverses the type of work required.
Surfactant
The air-tissue/water interface of the alveoli has a high surface tension. This surface tension is similar to the surface tension of water at the liquid-air interface of a water droplet that results in the bonding of the water molecules together. Surfactant is a complex mixture of phospholipids and lipoproteins that works to reduce the surface tension that exists between the alveoli tissue and the air found within the alveoli. By lowering the surface tension of the alveolar fluid, it reduces the tendency of alveoli to collapse.
Surfactant works like a detergent to reduce the surface tension and allows for easier inflation of the airways. When a balloon is first inflated, it takes a large amount of effort to stretch the plastic and start to inflate the balloon. If a little bit of detergent was applied to the interior of the balloon, then the amount of effort or work needed to begin to inflate the balloon would decrease, and it would become much easier to start blowing up the balloon. This same principle applies to the airways. A small amount of surfactant to the airway tissues reduces the effort or work needed to inflate those airways. Babies born prematurely sometimes do not produce enough surfactant. As a result, they suffer from respiratory distress syndrome , because it requires more effort to inflate their lungs. Surfactant is also important for preventing collapse of small alveoli relative to large alveoli.
Lung Resistance and Compliance
Pulmonary diseases reduce the rate of gas exchange into and out of the lungs. Two main causes of decreased gas exchange are compliance (how elastic the lung is) and resistance (how much obstruction exists in the airways). A change in either can dramatically alter breathing and the ability to take in oxygen and release carbon dioxide.
Examples of restrictive diseases are respiratory distress syndrome and pulmonary fibrosis. In both diseases, the airways are less compliant and they are stiff or fibrotic. There is a decrease in compliance because the lung tissue cannot bend and move. In these types of restrictive diseases, the intrapleural pressure is more positive and the airways collapse upon exhalation, which traps air in the lungs. Forced or functional vital capacity (FVC) , which is the amount of air that can be forcibly exhaled after taking the deepest breath possible, is much lower than in normal patients, and the time it takes to exhale most of the air is greatly prolonged (Figure \(\PageIndex{5}\)). A patient suffering from these diseases cannot exhale the normal amount of air.
Obstructive diseases and conditions include emphysema, asthma, and pulmonary edema. In emphysema, which mostly arises from smoking tobacco, the walls of the alveoli are destroyed, decreasing the surface area for gas exchange. The overall compliance of the lungs is increased, because as the alveolar walls are damaged, lung elastic recoil decreases due to a loss of elastic fibers, and more air is trapped in the lungs at the end of exhalation. Asthma is a disease in which inflammation is triggered by environmental factors. Inflammation obstructs the airways. The obstruction may be due to edema (fluid accumulation), smooth muscle spasms in the walls of the bronchioles, increased mucus secretion, damage to the epithelia of the airways, or a combination of these events. Those with asthma or edema experience increased occlusion from increased inflammation of the airways. This tends to block the airways, preventing the proper movement of gases (Figure \(\PageIndex{5}\)). Those with obstructive diseases have large volumes of air trapped after exhalation and breathe at a very high lung volume to compensate for the lack of airway recruitment.
Dead Space: V/Q Mismatch
Pulmonary circulation pressure is very low compared to that of the systemic circulation. It is also independent of cardiac output. This is because of a phenomenon called recruitment , which is the process of opening airways that normally remain closed when cardiac output increases. As cardiac output increases, the number of capillaries and arteries that are perfused (filled with blood) increases. These capillaries and arteries are not always in use but are ready if needed. At times, however, there is a mismatch between the amount of air (ventilation, V) and the amount of blood (perfusion, Q) in the lungs. This is referred to as ventilation/perfusion (V/Q) mismatch .
There are two types of V/Q mismatch. Both produce dead space , regions of broken down or blocked lung tissue. Dead spaces can severely impact breathing, because they reduce the surface area available for gas diffusion. As a result, the amount of oxygen in the blood decreases, whereas the carbon dioxide level increases. Dead space is created when no ventilation and/or perfusion takes place. Anatomical dead space or anatomical shunt, arises from an anatomical failure, while physiological dead space or physiological shunt, arises from a functional impairment of the lung or arteries.
An example of an anatomical shunt is the effect of gravity on the lungs. The lung is particularly susceptible to changes in the magnitude and direction of gravitational forces. When someone is standing or sitting upright, the pleural pressure gradient leads to increased ventilation further down in the lung. As a result, the intrapleural pressure is more negative at the base of the lung than at the top, and more air fills the bottom of the lung than the top. Likewise, it takes less energy to pump blood to the bottom of the lung than to the top when in a prone position. Perfusion of the lung is not uniform while standing or sitting. This is a result of hydrostatic forces combined with the effect of airway pressure. An anatomical shunt develops because the ventilation of the airways does not match the perfusion of the arteries surrounding those airways. As a result, the rate of gas exchange is reduced. Note that this does not occur when lying down, because in this position, gravity does not preferentially pull the bottom of the lung down.
A physiological shunt can develop if there is infection or edema in the lung that obstructs an area. This will decrease ventilation but not affect perfusion; therefore, the V/Q ratio changes and gas exchange is affected.
The lung can compensate for these mismatches in ventilation and perfusion. If ventilation is greater than perfusion, the arterioles dilate and the bronchioles constrict. This increases perfusion and reduces ventilation. Likewise, if ventilation is less than perfusion, the arterioles constrict and the bronchioles dilate to correct the imbalance.
Link to Learning
Visit this site to view the mechanics of breathing.
Summary
The structure of the lungs and thoracic cavity control the mechanics of breathing. Upon inspiration, the diaphragm contracts and lowers. The intercostal muscles contract and expand the chest wall outward. The intrapleural pressure drops, the lungs expand, and air is drawn into the airways. When exhaling, the intercostal muscles and diaphragm relax, returning the intrapleural pressure back to the resting state. The lungs recoil and airways close. The air passively exits the lung. There is high surface tension at the air-airway interface in the lung. Surfactant, a mixture of phospholipids and lipoproteins, acts like a detergent in the airways to reduce surface tension and allow for opening of the alveoli.
Breathing and gas exchange are both altered by changes in the compliance and resistance of the lung. If the compliance of the lung decreases, as occurs in restrictive diseases like fibrosis, the airways stiffen and collapse upon exhalation. Air becomes trapped in the lungs, making breathing more difficult. If resistance increases, as happens with asthma or emphysema, the airways become obstructed, trapping air in the lungs and causing breathing to become difficult. Alterations in the ventilation of the airways or perfusion of the arteries can affect gas exchange. These changes in ventilation and perfusion, called V/Q mismatch, can arise from anatomical or physiological changes.
Glossary
- alveolar ventilation
- how much air is in the alveoli
- anatomical dead space
- (also, anatomical shunt) region of the lung that lacks proper ventilation/perfusion due to an anatomical block
- compliance
- measurement of the elasticity of the lung
- dead space
- area in the lung that lacks proper ventilation or perfusion
- elastic recoil
- property of the lung that drives the lung tissue inward
- elastic work
- work conducted by the intercostal muscles, chest wall, and diaphragm
- flow-resistive
- work of breathing performed by the alveoli and tissues in the lung
- functional vital capacity (FVC)
- amount of air that can be forcibly exhaled after taking the deepest breath possible
- intercostal muscle
- muscle connected to the rib cage that contracts upon inspiration
- intrapleural space
- space between the layers of pleura
- obstructive disease
- disease (such as emphysema and asthma) that arises from obstruction of the airways; compliance increases in these diseases
- physiological dead space
- (also, physiological shunt) region of the lung that lacks proper ventilation/perfusion due to a physiological change in the lung (like inflammation or edema)
- pleura
- tissue layer that surrounds the lungs and lines the interior of the thoracic cavity
- pleurisy
- painful inflammation of the pleural tissue layers
- recruitment
- process of opening airways that normally remain closed when the cardiac output increases
- resistance
- measurement of lung obstruction
- respiratory distress syndrome
- disease that arises from a deficient amount of surfactant
- respiratory rate
- number of breaths per minute
- restrictive disease
- disease that results from a restriction and decreased compliance of the alveoli; respiratory distress syndrome and pulmonary fibrosis are examples
- surfactant
- detergent-like liquid in the airways that lowers the surface tension of the alveoli to allow for expansion
- ventilation/perfusion (V/Q) mismatch
- region of the lung that lacks proper alveolar ventilation (V) and/or arterial perfusion (Q)


13.5: Study Questions
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- Ly-Huong T. Pham, Tejal Desai-Naik, Laurie Hammond, & Wael Abdeljabbar
- ASCCC Open Educational Resources Initiative (OERI)
Summary
Information systems have changed how we work, play, and learn since the internet was introduced to the mass. We may be at a tipping point now with many significant advances of technologies that have been in research for many decades and are converged roughly at the same time as described in the above trends.
The adoption of many technologies has also been accelerated due to the 2020 Covid-19 Pandemic. Organizations will need to determine how they want to move forward to leverage opportunities and manage risks should any of the above trends become a reality.
As the world of information technology moves forward, we will be constantly challenged by new capabilities and innovations that will both amaze and disgust us. As we learned in chapter 12, many times, the new capabilities and powers that come with these new technologies will test us and require a new way of thinking about the world. Businesses and individuals alike need to be aware of these coming changes and prepare for them.
Study Questions
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Which countries are the biggest users of the Internet? Social media? Mobile?
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Which region had the largest Internet growth (in %) as of this year?
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Identify the top three social media networks by active users?
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How many people worldwide still need to be connected?
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Explain what a virtual environment is.
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What are two different applications of wearable technologies?
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What are two different applications of collaborative technologies?
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What capabilities do printable technologies have?
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What makes anything an Internet of Think?
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What is a UAV?
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What is Conditional Automation?
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What is a nanobot?
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What is a humanoid?
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Explain what Artificial intelligence is.
Exercises
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If you were going to start a new technology business, which of the emerging trends do you think would be the biggest opportunity? Do some original research to estimate the market size.
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What could privacy concerns be raised by collaborative technologies such as Zoom?
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Do some research about the first handgun printed using a 3-D printer and report some of the concerns raised.
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Write up an example of how the Internet of Things might provide a business with a competitive advantage.
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How do you think wearable technologies could improve overall healthcare?
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What potential problems do you see with a rise in the number of driverless cars? Do some independent research and write a two-page paper that describes where driverless cars are legal and what problems may occur.
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Seek out the latest presentation by Mary Meeker on “Internet Trends” (if you cannot find it, the video from 2019 is available https://www.youtube.com/watch?v=G_dwZB5h56E at the time of this writing). Write a one-page paper describing what the top three trends are, in your opinion.
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Visit ghsa.org to find what level of support your state has given to autonomous vehicles. Write a summary of the different levels of support for all states.


4.4A: The Cell Wall of Bacteria
- Recall the characteristics of a bacterial cell wall
Bacterial cells lack a membrane bound nucleus. Their genetic material is naked within the cytoplasm. Ribosomes are their only type of organelle. The term “nucleoid” refers to the region of the cytoplasm where chromosomal DNA is located, usually a singular, circular chromosome. Bacteria are usually single-celled, except when they exist in colonies. These ancestral cells reproduce by means of binary fission, duplicating their genetic material and then essentially splitting to form two daughter cells identical to the parent. A wall located outside the cell membrane provides the cell support, and protection against mechanical stress or damage from osmotic rupture and lysis.
The major component of the bacterial cell wall is peptidoglycan or murein. This rigid structure of peptidoglycan, specific only to prokaryotes, gives the cell shape and surrounds the cytoplasmic membrane. Peptidoglycan is a huge polymer of disaccharides (glycan) cross-linked by short chains of identical amino acids (peptides) monomers. The backbone of the peptidoglycan molecule is composed of two derivatives of glucose: N-acetylglucosamine (NAG) and N-acetlymuramic acid (NAM) with a pentapeptide coming off NAM and varying slightly among bacteria. The NAG and NAM strands are synthesized in the cytosol of the bacteria. They are connected by inter-peptide bridges. They are transported across the cytoplasmic membrane by a carrier molecule called bactoprenol. From the peptidoglycan inwards all bacterial cells are very similar. Going further out, the bacterial world divides into two major classes: Gram positive (Gram +) and Gram negative (Gram -). The cell wall provides important ligands for adherence and receptor sites for viruses or antibiotics.
Key Points
- A cell wall is a layer located outside the cell membrane found in plants, fungi, bacteria, algae, and archaea.
- A peptidoglycan cell wall composed of disaccharides and amino acids gives bacteria structural support.
- The bacterial cell wall is often a target for antibiotic treatment.
Key Terms
- binary fission : The process whereby a cell divides asexually to produce two daughter cells.


6.5: The Doppler Shift and Aberration
Learning Objectives
- What is aberration
Doppler Shifts
As an example, we generalize our previous discussion of the Doppler shift of light to \(3 + 1\) dimensions.
For clarity, let’s first show how the \(1+1\)-dimensional case works in our new notation. For a wave traveling to the left, we have \(ω\to = (ω,ω)\) (not \((ω,-ω)\) — see figure 6.6.1 (1). We now want to transform into the frame of an observer moving to the right with velocity \(v\) relative to the original frame. Because \(ω\to \) is a covector, we do this using the inverse Lorentz transformation. An ordinary Lorentz transformation would take a lightlike vector \((ω,ω)\) to \((ω/D,ω/D)\) (see section 3.2). The inverse Lorentz transformation gives \((Dω,Dω)\). The frequency has been shifted upward by the factor \(D\), as established previously.
In \(3 + 1\) dimensions, a spatial plane is determined by the light’s direction of propagation and the relative velocity of the source and observer, so this case reduces without loss of generality to \(2 + 1\) dimensions. The frequency four-vector must be lightlike, so its most general possible form is \((ω,ω cosθ,ω sinθ)\), where \(θ\) is interpreted as the angle between the direction of propagation and the relative velocity. In \(2+1\) dimensions, a Lorentz boost along the \(x\)- axis looks like this:
\[t' = \gamma t - v\gamma x\]
\[x' = - v\gamma t + \gamma x\]
\[y' = y\]
The inverse transformation is found by ﬂipping the sign of \(v\). Putting our frequency vector through an inverse Lorentz boost, we find
\[\omega ' = \gamma \omega (1 + v\cos \theta )\]
For \(θ = 0\) the Doppler factor reduces to
\[γ(1+v) = D\]
which recovers the \(1 + 1\)-dimensional result. For \(\theta = 90^{\circ}\), we have \(ω' = γω\), which is interpreted as a pure time dilation effect when the source’s motion is transverse to the line of sight.
To see the power of the mathematical tools we’ve developed in this chapter, you may wish to look at sections 6 and 7 of Einstein’s 1905 paper on special relativity, where a lengthy derivation is needed in order to arrive at the same result.
Aberration
Imagine that rain is falling vertically while you drive in a convertible with the top down. To you, the raindrops appear to be moving at some nonzero angle relative to vertical. This is referred to as aberration .
Definition: aberration
A world-line’s direction changes depending on one’s frame of reference.
In the street’s frame of reference, the angle between the rain’s three-velocity and the car’s is \(\theta = 90^{\circ}\), but in the car’s frame \(\theta ' \neq 90^{\circ}\). In this example, aberration is a large effect because the car’s speed \(v\) is comparable to the velocity \(u\) of the raindrops. To a snail crawling along the sidewalk at a much lower \(v\), the effect would be small. Using the small-angle approximation \(\tan \epsilon \approx \epsilon\), we find that for small \(v\), the difference \(∆θ = θ' - θ\) would be approximately \(v/u\), in units of radians.
Compared to a ray of light, we’re all like snails. For example, the earth’s orbital speed is about \(v ∼ 10^{-4}\) in units where the speed of light \(u = 1\), so we expect a maximum effect of about \(10^{-4}\) radians, or \(2'' \) of arc, which is small but not negligible for a telescope with a high-quality mount, being used at high magnification.
This estimate of astronomical aberration of light is roughly right, but we don’t expect it to be exact, both because of the small-angle approximation and because we calculated it using a Galilean picture of spacetime. Let’s calculate the exact result. As shown in Example 6.6.1, the direction of propagation of a light wave lies along the vector that is the dual to its frequency covector. Let’s call this direction of propagation \(\to u\). Reusing the expression for \(ω\to \) defined above, and arbitrarily fixing \(\to u\)’s timelike component to be \(1\), we have
\[\to u = (1,-\cos\theta ,-\sin\theta )\]
When this vector undergoes a boost \(v\) along the \(x\)- axis it becomes
\[\to u' = \left ( \gamma (1 + v\cos \theta ), \gamma (-v - v\cos \theta ), -\sin \theta \right )\]
The original angle
\[\theta = \tan^{-1}\frac{u_y}{u_x}\]
has been transformed to
\[\theta ' = \tan^{-1}\frac{u_y'}{u_x'}\]
the result being
\[\tan \theta ' = \frac{\sin \theta }{\gamma (\cos \theta + v)}\]
Example \(\PageIndex{1}\): A test of special relativity
An assumption underlying this treatment of aberration was that the speed of light was \(u = c\), regardless of the velocity of the source. Not all prerelativistic theories had this property, and one would expect that in such a theory, aberration would not be in accord with the relativistic result. In particular, suppose that we believed in Galilean spacetime, so that when a distant galaxy, receding from us at some speed \(w\), emitted a ray of light toward us, the light’s velocity in our frame was \(u = c - w\). That is, we imagine a theory in which emitting a ray of light is like shooting a bullet from a gun. Since aberration effects go approximately like \(v/u\), we would expect that the reduced \(u\) would lead to more aberration compared to the prediction of relativity.
To test theories of this type, Heckmann 1 used a \(24\)-inch reﬂector at Hamburg to take high-magnification photographic plates of a star field in Ursa Major containing \(11\) stars inside the Milky Way and \(5\) distant galaxies. Measurements of Doppler shifts showed that the galaxies were receding from us at velocities of about \(w = 0.05c\), whereas stars within the Milky Way move relative to us at speeds that are negligible in comparison. If, contrary to the relativistic prediction, this led to a \(5\%\) decrease in \(u\), then we would expect about a \(5\%\) increase in aberration for the galaxies compared to the stars.
Over the course of a year, the earth’s orbit carries it toward and away from Ursa Major, so that in the earth’s frame of reference, the stars and galaxies have varying velocities relative to us, and the \(∼20''\) aberration effect oscillates in direction. If the effect was different for the galaxies and the stars, then they ought to shift their apparent positions relative to one another. The shift ought to be on the order of \(5\%\) of \(2000\), or one second of arc. The results from the observations showed that these relative positions did not appear to vary at all over the course of a year, with the average relative shift being \(0.00±0.06''\) of arc. This difference in aberration is consistent with zero, as predicted by special relativity.
Example \(\PageIndex{2}\): The view of an ultrarelativistic observer
Figure \(\PageIndex{1}\) shows a visualization for an observer ﬂying through a cube at \(v = 0.99\). In figure \(\PageIndex{1}\) (1), the cube is shown in its own rest frame, where it has sides of unit length, and the observer, having already passed through, lies one unit to the right of the cube’scenter. The observer is facing to the right, away from the cube. The dashed line is a ray of light that travels from point \(P\) to the observer, and in this frame it appears as though the ray, arriving from \(\theta = 162^{\circ}\), would not make it into the observer’s eye.
But in the observer’s frame, figure \(\PageIndex{1}\) (2), the ray is at \(\theta ' = 47^{\circ}\), so it actually does fall within her field of view. The cube is length-contracted by a factor \(γ ≈ 7\). The ray was emitted earlier, when the cube was out in front of the observer, at the position shown by the dashed outline.
The image seen by the observer is shown in figure \(\PageIndex{1}\) (3). The circular outline defining the field of view represents \(\theta ' = 50^{\circ}\). Note that the relativistic length contraction is not at all what an observer sees optically. The optical observation is inﬂuenced by length contraction, but also by aberration and by the time it takes for light to propagate to the observer. The time of propagation is different for different parts of the cube, so in the observer’s frame, figure \(\PageIndex{1}\) (2), rays from different points had to be emitted when the cube was at different points in its motion, if those rays were to reach the eye.
A group at Australian National University has produced animations of similar scenes, which can be found online by searching for “optical effects of special relativity.”
The video shows photorealistic representations of reduced c scenes. This means that the speed of light has been slowed down from over one billion kilometres per hour to a speed of only one meter per second. The consequences of this fiction have been restricted to optical effects, and allows us to see special-relativistic effects not possible in everyday life.
It’s fun to imagine the view of an observer on board an ultrarelativistic starship. For \(v\) sufficiently close to \(1\), any angle \(\theta < 180^{\circ}\) transforms to a small \(θ'\). Thus, all light coming to this observer from the surrounding stars — even those in extreme backward directions! — is gathered into a small, bright patch of light that appears to come from straight ahead. Some visible light would be shifted into the extreme ultraviolet and infrared, while some infrared and ultraviolet light would become visible.


1.6: Writing Knowledge Transfers Easily
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- Cheryl E. Ball & Drew M. Loewe ed.
- West Virginia University via Digital Publishing Institute and West Virginia University Libraries
Author: Ellen C. Carillo. University of Connecticut Waterbury Campus.
It may not be an exaggeration to say that the very notion of writing instruction is based on a myth. Writing courses, like courses in many—maybe all—fields, are arranged in what we would call a vertical curriculum with students enrolling first in introductory courses like freshman English. This course may be followed by a research-writing or similarly advanced writing course and then, perhaps, by a more intense writing course that often serves as a capstone seminar in the student’s major. Certainly, there are variations of this model, but the structure is largely consistent across American post-secondary institutions in that students are expected to take introductory writing courses before taking more advanced ones. The reason curricula are designed in this way is so that students apply what they learn in those introductory courses to the more advanced courses that follow. This sounds like common sense, no? Yet, it is a myth that students will automatically apply— or transfer (the term most often used in educational psychology and composition studies) what they learn in their lower-level writing courses to their upper-level ones. They simply won’t.
Anecdotally, writing instructors see this all the time: students entering a second-semester writing course as if they had no previous college-level writing course (let alone one linked to that second-semester course), or students struggling with the writing component of their senior seminars despite their taking the required introductory writing courses and writing-intensive course(s) in their majors. Any number of variables might account for the experiences these anecdotes describe, but research corroborates that students don’t automatically transfer what they have learned about writing from one class into the next. The key word here is “automatically.” Transfer is not impossible, but it shouldn’t be taken for granted. It is a bad idea for writing programs and instructors to simply rely on curricula design to do their work for them—students will continue to be unprepared for their next writing course, let alone a course where writing is only one of the components.
Before describing the research that indicates why writing programs and instructors should not assume that knowledge transfer will automatically occur, it is perhaps wise to define the term transfer and offer some of its history. Transfer is a concept that has been studied for years by educational and cognitive psychologists, only recently becoming an interest of those in composition studies who teach and research writing development. Educational psychologists Gavriel Salomon and David Perkins define transfer as “instances in which learning in one context or with one set of materials impacts on performance in another context or with other related materials.” Research on transfer dates to the turn of the 20th century. Educational psychologists Edward Thorndike and Robert Woodworth conducted the earliest experiments in 1901. They found transfer to be rare and only successful when there were identical elements in the situations or contexts. Less than a decade later, educational psychologist Charles Judd challenged these findings and showed that if the learner was capable of understanding the abstract principle informing the problem or idea, she would be able to apply it in a different context even if all the same elements were not present. Judd showed that transfer was, in fact, possible in situations that were not characterized by identical elements and that the learner herself was an important component in the process.
While Judd showed that transfer was possible, he did not prove that it was automatic; it is the automaticity of transfer that is too often assumed in the teaching of writing. There is simply no basis for that assumption. Writing professors Anne Beaufort and Elizabeth Wardle both found in their research that even when students described their first-year writing courses as valuable, they were largely unable to generalize its teachings and thus imagine how that writing connected to other courses. For example, Wardle explains that students “did not appear to make even near connections of those skills, much less transfer those skills to very different contexts... no students suggested they were being asked to write a persuasive paper to be able to write persuasively in other courses.”
Although Judd’s experiments in 1908 indicated that transfer was possible, it would take nearly a century for those who teach and study writing to begin thinking about what to do about this.
36 Bad Ideas
The affirmative answer to this question is the antidote to this bad idea. Curricula must be redesigned with the concept of transfer in mind, and instructors must be trained to teach toward the goal of transfer. No matter how one teaches for transfer, the one consistent recommendation for doing so involves incorporating metacognitive exercises into writing courses. Metacognition literally means thinking about thinking, so metacognitive exercises in the classroom would ask students to think about what they are thinking and learning. These exercises give students opportunities to reflect on what they are learning about writing and—as such— potentially position students to transfer what they are learning. The same applies to everyone who suspects they will want to or need to transfer something they are learning to a future context. It would be useful to reflect on that learning and even anticipate where else it might be useful for people to transfer that knowledge to other situations since it will not automatically transfer.
In fact, it was less than a decade ago that these scholars regularly began asking questions such as: If transfer is possible, are there certain ways we can teach writing to promote transfer?
Most recently, Kathleen Yancey and her colleagues tested the benefits of deliberately teaching for transfer. They found that students in courses with instructors who taught for transfer did transfer their writing skills and knowledge more regularly than students who were in other types of writing courses. My sense is that more studies that corroborate these findings are on their way. If that’s the case, and these studies are taken as seriously as they should be, colleges and universities will see the emergence of new curricula and teaching practices that no longer perpetuate the myth of automatic transfer. The broader implications of studies on teaching for transfer are just as striking. By studying transfer, all of us come to a better understanding about how we and others learn in our everyday lives and what types of learning experiences facilitate transfer not just in academic contexts but across all the contexts we inhabit, including—but certainly not limited to—school, home, and work.
Further Reading
For foundational work on the transfer of learning from the field of education, see David Perkins and Gavriel Salomon’s article “Are Cognitive Skills Context Bound?” and summarizing encyclopedia entry, “Transfer of Learning.” Building upon this work, scholars in
About What Good Writing Is 37
rhetoric and composition have written extensively about how learning transfers from one writing course or writing situation to another. For scholarly books on problems of transfer, see Anne Beaufort’s College Writing and Beyond , my book Securing a Place for Reading in Composition: The Importance of Teaching for Transfer , Kathleen Blake Yancey, Liane Robertson, and Kara Taczak’s Writing Across Contexts , and Rebecca Nowacek’s Agents of Integration: Understanding Transfer as a Rhetorical Act. For journal articles, see Linda Bergmann and Janet Zepernick’s “Disciplinarity and Transference: Students’ Perceptions of Learning to Write,” Christiane Donahue’s “Transfer, Portability, Generalization: (How) Does Composition Expertise ‘Carry’?,” Julie Foertsch’s “Where Cognitive Psychology Applies: How Theories about Memory and Transfer Can Influence Composition Pedagogy,” Dana Lynn Driscoll’s “Connected, Disconnected, or Uncertain: Student Attitudes about Future Writing Contexts and Perceptions of Transfer from First-Year Writing to the Disciplines,” and Gerald Nelms and Rhonda Leathers Dively’s “Perceived Roadblocks to Transferring Knowledge from First-Year Composition to WritingIntensive Major Courses: A Pilot Study.”
Keywords
composition studies, metacognition, transfer of learning, vertical curriculum
Author Bio
Ellen C. Carillo, Ph.D. is an associate professor at the University of Connecticut and the writing program coordinator at its Waterbury Campus. Her administrative work involves directing the Writing Center, supervising the first-year writing program, and supporting faculty who teach writing-intensive courses across the disciplines. She has written a book, as well as articles and chapters about the importance of teaching for transfer. She incorporates this approach to teaching into the literature and writing courses she teaches. Ellen has earned two grants to explore transfer in different settings and has served as an advisor for graduate students who are completing dissertations on transfer.


8.4: Conflict Management
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Ideally, through proper planning and effective communication your group will avoid conflict. Any collaborative project whether in the classroom or the workplace, however, has the potential for conflict. Learning effective conflict management skills can help you in many facets of your life. A key element of effective conflict management is building emotional intelligence . If you remember from earlier in this text, emotional intelligence is the ability to understand and manage one’s own emotions, as well as the emotions of others 28 . Research has shown that students with high emotional intelligence have better interpersonal relationships, and may be more likely to stay in college and have greater academic success. 29
Recognize the emotions of the person you are working with. Pay attention to body language and facial cues. Reflect on which emotions generate that same type of body language from you.
Be empathetic. Try to experience the situation from the other person’s point of view. Really consider for a moment how you would feel if you were in their situation.
Practice active listening. Pay close attention to what the other person is saying. Ask clarifying questions. Summarize what was said to you.
James is upset during a meeting with his group. He takes a moment to reflect on his own emotions. He feels that no one is listening to his ideas and is worried that the deadline for the project is soon. James is able to label his emotions as frustration and anxiety. James becomes aware that he has tensed up his body and was using a harsh tone of voice. He then notices that Mary is sitting with her arms crossed and has stopped participating in the conversation. He realizes that he wasn't giving Mary an opportunity to share her ideas either. James focuses on relaxing his body. Using a calm voice, he apologizes and asks Mary what her idea was.
28 Mayer, J. D., & Salovey, P. (1997). What is emotional intelligence? In P. Salovey & D. J. Sluyter, (Eds.), Emotional development and emotional intelligence: Educational implications. New York: Basic Books.
29 Parker, J.D.A., Summerfeldt, L.J., Hogan, M.J., & Majeski, S. (2004). Emotional intelligence and academic success: Examining the transition from high school to university. Personality and Individual Differences, 36, 163-172.


5.3.2: Definitions and Types of Insurance
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Learning Objectives
- Know the basic types of insurance for individuals.
- Name and describe the various kinds of business insurance.
Certain terms are usefully defined at the outset. Insurance is a contract of reimbursement. For example, it reimburses for losses from specified perils, such as fire, hurricane, and earthquake. An insurer is the company or person who promises to reimburse. The insured (sometimes called the assured) is the one who receives the payment, except in the case of life insurance, where payment goes to the beneficiary named in the life insurance contract. The premium is the consideration paid by the insured—usually annually or semiannually—for the insurer’s promise to reimburse. The contract itself is called the policy . The events insured against are known as risks or perils .
Regulation of insurance is left mainly in the hands of state, rather than federal, authorities. Under the McCarran-Ferguson Act, Congress exempted state-regulated insurance companies from the federal antitrust laws. Every state now has an insurance department that oversees insurance rates, policy standards, reserves, and other aspects of the industry. Over the years, these departments have come under fire in many states for being ineffective and “captives” of the industry. Moreover, large insurers operate in all states, and both they and consumers must contend with fifty different state regulatory schemes that provide very different degrees of protection. From time to time, attempts have been made to bring insurance under federal regulation, but none have been successful.
We begin with an overview of the types of insurance, from both a consumer and a business perspective. Then we examine in greater detail the three most important types of insurance: property, liability, and life.
Public and Private Insurance
Sometimes a distinction is made between public and private insurance. Public (or social) insurance includes Social Security, Medicare, temporary disability insurance, and the like, funded through government plans. Private insurance plans, by contrast, are all types of coverage offered by private corporations or organizations. The focus of this chapter is private insurance.
Types of Insurance for the Individual
Life Insurance
Life insurance provides for your family or some other named beneficiaries on your death. Two general types are available: term insurance provides coverage only during the term of the policy and pays off only on the insured’s death; whole-life insurance provides savings as well as insurance and can let the insured collect before death.
Health Insurance
Health insurance covers the cost of hospitalization, visits to the doctor’s office, and prescription medicines. The most useful policies, provided by many employers, are those that cover 100 percent of the costs of being hospitalized and 80 percent of the charges for medicine and a doctor’s services. Usually, the policy will contain a deductible amount; the insurer will not make payments until after the deductible amount has been reached. Twenty years ago, the deductible might have been the first $100 or $250 of charges; today, it is often much higher.
Disability Insurance
A disability policy pays a certain percentage of an employee’s wages (or a fixed sum) weekly or monthly if the employee becomes unable to work through illness or an accident. Premiums are lower for policies with longer waiting periods before payments must be made: a policy that begins to pay a disabled worker within thirty days might cost twice as much as one that defers payment for six months.
Homeowner’s Insurance
A homeowner’s policy provides insurance for damages or losses due to fire, theft, and other named perils. No policy routinely covers all perils. The homeowner must assess his needs by looking to the likely risks in his area—earthquake, hailstorm, flooding, and so on. Homeowner’s policies provide for reduced coverage if the property is not insured for at least 80 percent of its replacement costs. In inflationary times, this requirement means that the owner must adjust the policy limits upward each year or purchase a rider that automatically adjusts for inflation. Where property values have dropped substantially, the owner of a home (or a commercial building) might find savings in lowering the policy’s insured amount.
Automobile Insurance
Automobile insurance is perhaps the most commonly held type of insurance. Automobile policies are required in at least minimum amounts in all states. The typical automobile policy covers liability for bodily injury and property damage, medical payments, damage to or loss of the car itself, and attorneys’ fees in case of a lawsuit.
Other Liability Insurance
In this litigious society, a person can be sued for just about anything: a slip on the walk, a harsh and untrue word spoken in anger, an accident on the ball field. A personal liability policy covers many types of these risks and can give coverage in excess of that provided by homeowner’s and automobile insurance. Such umbrella coverage is usually fairly inexpensive, perhaps $250 a year for $1 million in liability.
Types of Business Insurance
Workers’ Compensation
Almost every business in every state must insure against injury to workers on the job. Some may do this through self-insurance—that is, by setting aside certain reserves for this contingency. Most smaller businesses purchase workers’ compensation policies, available through commercial insurers, trade associations, or state funds.
Automobile Insurance
Any business that uses motor vehicles should maintain at least a minimum automobile insurance policy on the vehicles, covering personal injury, property damage, and general liability.
Property Insurance
No business should take a chance of leaving unprotected its buildings, permanent fixtures, machinery, inventory, and the like. Various property policies cover damage or loss to a company’s own property or to property of others stored on the premises.
Malpractice Insurance
Professionals such as doctors, lawyers, and accountants will often purchase malpractice insurance to protect against claims made by disgruntled patients or clients. For doctors, the cost of such insurance has been rising over the past thirty years, largely because of larger jury awards against physicians who are negligent in the practice of their profession.
Business Interruption Insurance
Depending on the size of the business and its vulnerability to losses resulting from damage to essential operating equipment or other property, a company may wish to purchase insurance that will cover loss of earnings if the business operations are interrupted in some way—by a strike, loss of power, loss of raw material supply, and so on.
Liability Insurance
Businesses face a host of risks that could result in substantial liabilities. Many types of policies are available, including policies for owners, landlords, and tenants (covering liability incurred on the premises); for manufacturers and contractors (for liability incurred on all premises); for a company’s products and completed operations (for liability that results from warranties on products or injuries caused by products); for owners and contractors (protective liability for damages caused by independent contractors engaged by the insured); and for contractual liability (for failure to abide by performances required by specific contracts).
Some years ago, different types of individual and business coverage had to be purchased separately and often from different companies. Today, most insurance is available on a package basis, through single policies that cover the most important risks. These are often called multiperil policies.
Key Takeaway
Although insurance is a need for every US business, and many businesses operate in all fifty states, regulation of insurance has remained at the state level. There are several forms of public insurance (Social Security, disability, Medicare) and many forms of private insurance. Both individuals and businesses have significant needs for various types of insurance, to provide protection for health care, for their property, and for legal claims made against them by others.
Exercises
- Theresa Conley is joining the accounting firm of Hunter and Patton in Des Moines, Iowa. She is a certified public accountant. What kind of insurance will she (or the firm, on her behalf) need to buy because of her professional activities?
- Nate Johnson has just signed a franchise agreement with Papa Luigi’s Pizza and will be operating his own Papa Luigi’s store in Lubbock, Texas. The franchise agreement requires that he personally contract for “all necessary insurance” for the successful operation of the franchise. He expects to have twelve employees, five full-time and seven part-time (the delivery people), at his location, which will be on a busy boulevard in Lubbock and will offer take-out only. Pizza delivery employees will be using their own automobiles to deliver orders. What kinds of insurance will be “necessary”?


14.5: Introduction to Interviewing
What you’ll learn to do: Discuss effective interview strategies and prepare for common interview questions
Landing a job isn’t as easy as applying for one, plain and simple. In the end, you’ve only got one shot with a prospective employer before they more on to more qualified applicants, so do everything you can to show that you’re the person they need. This module will help you:
- Break down the interview process, and show you how to prepare for the steps within
- Apply helpful tips and prepare answers to practice questions so you are comfortable highlighting your core skills and experience during an interview
Contributors and Attributions
CC licensed content, Shared previously
- 7 Incredible Tips to a Successful Job Interview. Authored by : Melissa Hart. Provided by : HealthGrad. Located at : https://www.healthgrad.com/topics/7-incredible-tips-successful-job-interview/ . License : CC BY: Attribution


5.5: Application I - Translating from Verbal to Mathematical Expressions
Translating from Verbal to Mathematical Expressions
To solve a problem using algebra, we must first express the problem algebraically. To express a problem algebraically, we must scrutinize the wording of the problem to determine the variables and constants that are present and the relationships among them. Then we must translate the verbal phrases and statements to algebraic expressions and equations.
To help us translate verbal expressions to mathematics, we can use the following table as a mathematics dictionary.
| Word or Phrase | Mathematical Operation |
| Sum, sum of, added to, increased by, more than, plus, and | \(+\) |
| Difference, minus, subtracted from, decreased by, less, less than | \(-\) |
| Product, the product of, of, muitiplied by, times | \(\cdot\) |
| Quotient, divided by, ratio | \(\div\) |
| Equals, is equal to, is, the result is, becomes | = |
| A number, an unknown quantity, an unknown, a quantity | \(x\) (or any symbol) |
Sample Set A
Translate the following phrases or sentences into mathematical expressions or equations.
\(\underbrace{\underbrace{\text { six }}_{6} \underbrace{\text { more than }}_{+} \underbrace{\text { a number }}_{x}}_{6+x} \text { . }\)
\(\underbrace{\underbrace{\text { Fifteen }}_{15} \underbrace{\text { minus }}_{15} \underbrace{\text { a number }}_{x}}_{15-x} \text { . }\)
\(\underbrace{\underbrace{\text { A quantity }}_{y} \underbrace{\text { less }}_{-} \underbrace{\text { eight. }}_{8}}_{y-8}\)
\(\underbrace{\underbrace{\text { Twice }}_{2 \cdot} \underbrace{\text { a number }}_{x} \underbrace{\text { is }}_{=} \underbrace{\operatorname{ten} .}_{10}}_{2 x=10}\)
\(\underbrace{\underbrace{\text { One half }}_{\dfrac{1}{2}} \underbrace{\text { of }}_{\cdot} \underbrace{\text { a number }}_{\mathbf{z}} \underbrace{\text { is }}_{=} \underbrace{\text { twenty }}_{20}}_{\dfrac{1}{2} z=20}\)
\(\underbrace{\underbrace{\text{Three}}_{3} \underbrace{\text{times}}_{\cdot} \underbrace{\text{a number}}_{y} \underbrace{\text{is}}_{=} \underbrace{\text{five}}_{5} \underbrace{\text{more than}}_{+} \underbrace{\text{twice}}_{2\cdot} \underbrace{\text{the same number}}_{y}}_{3y=5+2y}\)
Practice Set A
Translate the following phrases or sentences into mathematical expressions or equations.
Eleven more than a number.
- Answer
-
\(11+x\)
Nine minus a number.
- Answer
-
\(9−x\)
A quantity less twenty.
- Answer
-
\(x−20\)
Four times a number is thirty two.
- Answer
-
\(4x=32\)
One third of a number is six.
- Answer
-
\(\dfrac{x}{3} = 6\)
Ten times a number is eight more than five times the same number.
- Answer
-
\(10x=8+5x\)
Sometimes the structure of the sentence indicates the use of grouping symbols.
Sample Set B
Translate the following phrases or sentences into mathematical expressions or equations.
\(\underbrace{\underbrace{\text { A number divided by five, }}_{(\mathrm{x} \div 5)} \underbrace{\text { minus }}_{-} \underbrace{\text { ten, }}_{10} \underbrace{\text { is }}_{=} \underbrace{\text { fifteen. }}_{15}}_{\dfrac{x}{5}-10=15}\)
Commas set off terms
\(\begin{array}{c}
\underbrace{\text { Eight }}_{8} \underbrace{\text { divided by }}_{\div} \underbrace{\text { five more than a number }}_{(5+x)} \underbrace{\text { is }}_{=} \underbrace{\text { ten }}_{10} \\
\text { The wording indicates this is to be considered as a single quantity. } \\
\dfrac{8}{5+x}=10
\end{array}\)
\(\underbrace{\underbrace{\text { A number }}_{x} \underbrace{\text { multiplied by }}_{\text {, }} \underbrace{\text { ten more than itself }}_{(10+x)} \underbrace{\text { is }}_{=} \underbrace{\text { twenty. }}_{20}}_{x(10+x)=20}\)
A number plus one is divided by three times the number minus twelve and the result is four.
\(
\begin{aligned}
(x+1) \div(3 \cdot x-12) &=4 \\
\dfrac{x+1}{3 x-12} &=4
\end{aligned}
\)
Notice that since the phrase "three times the number minus twelve" does not contain a comma, we get the expression $3 x-12$. If the phrase had appeared as "three times the number, minus twelve," the result would have been
\(
\dfrac{x+1}{3 x}-12=4
\)
Some phrases and sentences do not translate directly. We must be careful to read them properly. The word from often appears in such phrases and sentences. The word from means "a point of departure for motion." The following translation will illustrate this use.
The word from indicates the motion (subtraction) is to begin at the point of "some quantity."
Eight less than some quantity. Notice that less than could be replaced with from .
\(x-8\)
Practice Set B
Translate the following phrases and sentences into mathematical expressions or equations.
A number divided by sixteen, plus one, is five.
- Answer
-
\(\dfrac{x}{16}+1 = 5\)
Seven times two more than a number is twenty-one.
- Answer
-
\(7(2+x) = 21\)
A number divided by two more than itself is zero.
- Answer
-
\(\dfrac{x}{2+x} = 0\)
A number minus five is divided by twice the number plus three and the result is seventeen.
- Answer
-
\(\dfrac{x-5}{2x+3} = 17\)
Fifty-two is subtracted from some quantity.
- Answer
-
\(x-52\)
An unknown quantity is subtracted from eleven and the result is five less than the unknown quantity.
- Answer
-
\(11−x=x−5\)
Exercises
For the following problems, translate the following phrases or sentences into mathematical expressions or equations.
A quantity less four.
- Answer
-
\(a−4\)
Eight more than a number.
A number plus seven.
- Answer
-
\(b+7\)
A number minus three.
Negative five plus an unknown quantity.
- Answer
-
\(−5+c\)
Negative sixteen minus some quantity.
Fourteen added to twice a number.
- Answer
-
\(2d+14\)
Ten added to three times some number.
One third minus an unknown quantity.
- Answer
-
\(\dfrac{1}{3}-e\)
Twice a number is eleven.
Four ninths of a number is twenty-one.
- Answer
-
\(\dfrac{4}{9}f = 21\)
One third of a number is two fifths.
Three times a number is nine more than twice the number.
- Answer
-
\(3g=2g+9\)
Five times a number is that number minus two.
Twice a number added to six results in thirty.
- Answer
-
\(2h+6=30\)
Ten times a number less four results in sixty-six.
A number less twenty-five is equal to \(3.019\).
- Answer
-
\(k−25=3.019\)
Seven more than some number is five more than twice the number.
When a number is divided by four, the result is sixty-eight.
- Answer
-
\(\dfrac{m}{4} = 68\)
Eleven fifteenths of two more than a number is eight.
One tenth of a number is that number less one.
- Answer
-
\(\dfrac{n}{10} = n-1\)
Two more than twice a number is one half the number less three.
A number is equal to itself plus four times itself.
- Answer
-
\(x=x+4x\)
Three fifths of a quantity added to the quantity itself is thirty-nine.
A number plus seven is divided by two and the result is twenty-two.
- Answer
-
\(\dfrac{Q+7}{2} = 22\)
Ten times a number minus one is divided by fourteen and the result is one.
A number is added to itself then divided by three. This result is then divided by three. The entire result is fifteen.
- Answer
-
\(\dfrac{\dfrac{r+r}{3}}{3} = 15\)
Ten divided by two more than a number is twenty-one.
Five divided by a number plus six is fourteen.
- Answer
-
\(\dfrac{5}{s+6} = 14\)
Twelve divided by twice a number is fifty-five.
Twenty divided by eight times a number added to one is nine.
- Answer
-
\(\dfrac{20}{8x}+1 = 9\)
A number divided by itself, plus one, results in seven.
A number divided by ten, plus four, results in twenty-four.
- Answer
-
\(\dfrac{v}{10} + 4 = 24\)
A number plus six, divided by two, is seventy-one.
A number plus six, divided by two, plus five, is forty-three.
- Answer
-
\(\dfrac{w+6}{2}+5 = 43\)
A number multiplied by itself added to five is thirty-one.
A quantity multiplied by seven plus twice itself is ninety.
- Answer
-
\(7y+2y=90\)
A number is increased by one and then multiplied by five times itself. The result is eighty-four.
A number is added to six and that result is multiplied by thirteen. This result is then divided by six times the number. The entire result is equal to fifty-nine.
- Answer
-
\(\dfrac{(z+16)13}{6z} = 59\)
A number is subtracted from ten and that result is multiplied by four. This result is then divided by three more than the number. The entire result is equal to six.
An unknown quantity is decreased by eleven. This result is then divided by fifteen. Now, one is subtracted from this result and five is obtained.
- Answer
-
\(\dfrac{x-11}{15}-1 = 5\)
Ten less than some number.
Five less than some unknown number.
- Answer
-
\(n−5\)
Twelve less than a number.
One less than an unknown quantity.
- Answer
-
\(m−1\)
Sixteen less than some number is forty-two.
Eight less than some unknown number is three.
- Answer
-
\(p−8=3\)
Seven is added to ten less than some number. The result is one.
Twenty-three is divided by two less than twice some number and the result is thirty-four.
- Answer
-
\(\dfrac{23}{2n-2} = 34\)
Exercises for Review
Supply the missing word. The point on a line that is associated with a particular number is called the of that number.
- Answer
-
graph
Supply the missing word. An exponent records the number of identical in a multiplication.
Write the algebraic definition of the absolute value of the number \(a\).
- Answer
-
\(|a|=\left\{\begin{array}{l}
a, \text { if } a \geq 0 \\
-a, \text { if } a<0
\end{array}\right.\)
Solve the equation \(4y+5=−3\).
Solve the equation \(2(3x+1)−5x=4(x−6)+17\).
- Answer
-
\(x=3\)
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