13.4: Testing the Effectiveness of Antiseptics and Disinfectants
- Describe why the phenol coefficient is used
- Compare and contrast the disk-diffusion, use-dilution, and in-use methods for testing the effectiveness of antiseptics, disinfectants, and sterilants
The effectiveness of various chemical disinfectants is reflected in the terms used to describe them. Chemical disinfectants are grouped by the power of their activity, with each category reflecting the types of microbes and viruses its component disinfectants are effective against. High-level germicides have the ability to kill vegetative cells, fungi, viruses, and endospores, leading to sterilization, with extended use.
However, several environmental conditions influence the potency of an antimicrobial agent and its effectiveness. For example, length of exposure is particularly important, with longer exposure increasing efficacy. Similarly, the concentration of the chemical agent is also important, with higher concentrations being more effective than lower ones. Temperature, pH, and other factors can also affect the potency of a disinfecting agent.
One method to determine the effectiveness of a chemical agent includes swabbing surfaces before and after use to confirm whether a sterile field was maintained during use. Additional tests are described in the sections that follow. These tests allow for the maintenance of appropriate disinfection protocols in clinical settings, controlling microbial growth to protect patients, health-care workers, and the community.
Phenol Coefficient
The effectiveness of a disinfectant or antiseptic can be determined in a number of ways. Historically, a chemical agent’s effectiveness was often compared with that of phenol, the first chemical agent used by Joseph Lister. In 1903, British chemists Samuel Rideal (1863–1929) and J. T. Ainslie Walker (1868–1930) established a protocol to compare the effectiveness of a variety of chemicals with that of phenol, using as their test organisms Staphylococcus aureus (a gram-positive bacterium) and Salmonella enterica serovar Typhi (a gram-negative bacterium). They exposed the test bacteria to the antimicrobial chemical solutions diluted in water for 7.5 minutes. They then calculated a phenol coefficient for each chemical for each of the two bacteria tested. A phenol coefficient of 1.0 means that the chemical agent has about the same level of effectiveness as phenol. A chemical agent with a phenol coefficient of less than 1.0 is less effective than phenol. An example is formalin, with phenol coefficients of 0.3 ( S. aureus ) and 0.7 ( S. enterica serovar Typhi). A chemical agent with a phenol coefficient greater than 1.0 is more effective than phenol, such as chloramine, with phenol coefficients of 133 and 100, respectively. Although the phenol coefficient was once a useful measure of effectiveness, it is no longer commonly used because the conditions and organisms used were arbitrarily chosen.
What are the differences between the three levels of disinfectant effectiveness?
Disk-Diffusion Method
The disk-diffusion method involves applying different chemicals to separate, sterile filter paper disks (Figure \(\PageIndex{1}\)). The disks are then placed on an agar plate that has been inoculated with the targeted bacterium and the chemicals diffuse out of the disks into the agar where the bacteria have been inoculated. As the “lawn” of bacteria grows, zones of inhibition of microbial growth are observed as clear areas around the disks. Although there are other factors that contribute to the sizes of zones of inhibition (e.g., whether the agent is water soluble and able to diffuse in the agar), larger zones typically correlate to increased inhibition effectiveness of the chemical agent. The diameter across each zone is measured in millimeters.
When comparing the activities of two disinfectants against the same microbe, using the disk-diffusion assay, and assuming both are water soluble and can easily diffuse in the agar, would a more effective disinfectant have a larger zone of inhibition or a smaller one?
Use-Dilution Test
Other methods are also used for measuring the effectiveness of a chemical agent in clinical settings. The use-dilution test is commonly used to determine a chemical’s disinfection effectiveness on an inanimate surface. For this test, a cylinder of stainless steel is dipped in a culture of the targeted microorganism and then dried. The cylinder is then dipped in solutions of disinfectant at various concentrations for a specified amount of time. Finally, the cylinder is transferred to a new test tube containing fresh sterile medium that does not contain disinfectant, and this test tube is incubated. Bacterial survival is demonstrated by the presence of turbidity in the medium, whereas killing of the target organism on the cylinder by the disinfectant will produce no turbidity.
The Association of Official Agricultural Chemists International (AOAC), a nonprofit group that establishes many protocol standards, has determined that a minimum of 59 of 60 replicates must show no growth in such a test to achieve a passing result, and the results must be repeatable from different batches of disinfectant and when performed on different days. Disinfectant manufacturers perform use-dilution tests to validate the efficacy claims for their products, as designated by the EPA.
Is the use-dilution test performed in a clinical setting? Why?
In-Use Test
An in-use test can determine whether an actively used solution of disinfectant in a clinical setting is microbially contaminated (Figure \(\PageIndex{2}\)). A 1-mL sample of the used disinfectant is diluted into 9 mL of sterile broth medium that also contains a compound to inactivate the disinfectant. Ten drops, totaling approximately 0.2 mL of this mixture, are then inoculated onto each of two agar plates. One plate is incubated at 37 °C for 3 days and the other is incubated at room temperature for 7 days. The plates are monitored for growth of microbial colonies. Growth of five or more colonies on either plate suggests that viable microbial cells existed in the disinfectant solution and that it is contaminated. Such in-use tests monitor the effectiveness of disinfectants in the clinical setting.
What does a positive in-use test indicate?
Despite antibiotic treatment, Roberta’s symptoms worsened. She developed pyelonephritis, a severe kidney infection, and was rehospitalized in the intensive care unit (ICU). Her condition continued to deteriorate, and she developed symptoms of septic shock. At this point, her physician ordered a culture from her urine to determine the exact cause of her infection, as well as a drug sensitivity test to determine what antibiotics would be effective against the causative bacterium. The results of this test indicated resistance to a wide range of antibiotics, including the carbapenems, a class of antibiotics that are used as the last resort for many types of bacterial infections. This was an alarming outcome, suggesting that Roberta’s infection was caused by a so-called superbug: a bacterial strain that has developed resistance to the majority of commonly used antibiotics. In this case, the causative agent belonged to the carbapenem-resistant Enterobacteriaceae (CRE), a drug-resistant family of bacteria normally found in the digestive system (Figure \(\PageIndex{3}\)). When CRE is introduced to other body systems, as might occur through improperly cleaned surgical instruments, catheters, or endoscopes, aggressive infections can occur.
CRE infections are notoriously difficult to treat, with a 40%–50% fatality rate. To treat her kidney infection and septic shock, Roberta was treated with dialysis, intravenous fluids, and medications to maintain blood pressure and prevent blood clotting. She was also started on aggressive treatment with intravenous administration of a new drug called tigecycline, which has been successful in treating infections caused by drug-resistant bacteria.
After several weeks in the ICU, Roberta recovered from her CRE infection. However, public health officials soon noticed that Roberta’s case was not isolated. Several patients who underwent similar procedures at the same hospital also developed CRE infections, some dying as a result. Ultimately, the source of the infection was traced to the duodenoscopes used in the procedures. Despite the hospital staff meticulously following manufacturer protocols for disinfection, bacteria, including CRE, remained within the instruments and were introduced to patients during procedures.
Carbapenem-resistant Enterobacteriaceae infections due to contaminated endoscopes have become a high-profile problem in recent years. Several CRE outbreaks have been traced to endoscopes, including a case at Ronald Reagan UCLA Medical Center in early 2015 in which 179 patients may have been exposed to a contaminated endoscope. Seven of the patients developed infections, and two later died. Several lawsuits have been filed against Olympus, the manufacturer of the endoscopes. Some claim that Olympus did not obtain FDA approval for design changes that may have led to contamination, and others claim that the manufacturer knowingly withheld information from hospitals concerning defects in the endoscopes.
Lawsuits like these raise difficult-to-answer questions about liability. Invasive procedures are inherently risky, but negative outcomes can be minimized by strict adherence to established protocols. Who is responsible, however, when negative outcomes occur due to flawed protocols or faulty equipment? Can hospitals or health-care workers be held liable if they have strictly followed a flawed procedure? Should manufacturers be held liable—and perhaps be driven out of business—if their lifesaving equipment fails or is found defective? What is the government’s role in ensuring that use and maintenance of medical equipment and protocols are fail-safe?
Protocols for cleaning or sterilizing medical equipment are often developed by government agencies like the FDA, and other groups, like the AOAC, a nonprofit scientific organization that establishes many protocols for standard use globally. These procedures and protocols are then adopted by medical device and equipment manufacturers. Ultimately, the end-users (hospitals and their staff) are responsible for following these procedures and can be held liable if a breach occurs and patients become ill from improperly cleaned equipment.
Unfortunately, protocols are not infallible, and sometimes it takes negative outcomes to reveal their flaws. In 2008, the FDA had approved a disinfection protocol for endoscopes, using glutaraldehyde (at a lower concentration when mixed with phenol), o-phthalaldehyde, hydrogen peroxide, peracetic acid, and a mix of hydrogen peroxide with peracetic acid. However, subsequent CRE outbreaks from endoscope use showed that this protocol alone was inadequate.
As a result of CRE outbreaks, hospitals, manufacturers, and the FDA are investigating solutions. Many hospitals are instituting more rigorous cleaning procedures than those mandated by the FDA. Manufacturers are looking for ways to redesign duodenoscopes to minimize hard-to-reach crevices where bacteria can escape disinfectants, and the FDA is updating its protocols. In February 2015, the FDA added new recommendations for careful hand cleaning of the duodenoscope elevator mechanism (the location where microbes are most likely to escape disinfection), and issued more careful documentation about quality control of disinfection protocols (Figure \(\PageIndex{4}\)).
There is no guarantee that new procedures, protocols, or equipment will completely eliminate the risk for infection associated with endoscopes. Yet these devices are used successfully in 500,000–650,000 procedures annually in the United States, many of them lifesaving. At what point do the risks outweigh the benefits of these devices, and who should be held responsible when negative outcomes occur?
Key Concepts and Summary
- Chemical disinfectants are grouped by the types of microbes and infectious agents they are effective against. High-level germicides kill vegetative cells, fungi, viruses, and endospores, and can ultimately lead to sterilization. Intermediate-level germicides cannot kill all viruses and are less effective against endospores. Low-level germicides kill vegetative cells and some enveloped viruses, but are ineffective against endospores.
- The effectiveness of a disinfectant is influenced by several factors, including length of exposure, concentration of disinfectant, temperature, and pH.
- Historically, the effectiveness of a chemical disinfectant was compared with that of phenol at killing Staphylococcus aureus and Salmonella enterica serovar Typhi, and a phenol coefficient was calculated.
- The disk-diffusion method is used to test the effectiveness of a chemical disinfectant against a particular microbe.
- The use-dilution test determines the effectiveness of a disinfectant on a surface. In-use tests can determine whether disinfectant solutions are being used correctly in clinical settings.


5.16: What are Blood Pressure Ranges?
Blood pressure is reported in mm Hg (pronounced millimetres of mercury), in which the systolic is the numerator and diastolic is the denominator. See Table 5.1 for an overview of estimated blood pressure ranges for healthy individuals.
Table 5.1: Estimated Blood Pressure Ranges
| Age | Systolic Range | Diastolic Range |
|---|---|---|
| Newborn to 1 month | 45–80 mm Hg | 30–55 mm Hg |
| One to 12 months | 65–100 mm Hg | 35–65 mm Hg |
| Young child (1–5 years) | 80–115 mm Hg | 55–80 mm Hg |
| Older child (6–13 years) | 80–120 mm Hg | 45–80 mm Hg |
| Adolescent (14–18 years) | 90–120 mm Hg | 50–80 mm Hg |
| Adult (19–40 years) | 95–135 mm Hg | 60–80 mm Hg |
| Adult (41–60 years) | 110–145 mm Hg | 70–90 mm Hg |
| Older adult (61 and older) | 95–145 mm Hg | 70–90 mm Hg |
Points to Consider
The average blood pressure for an adult is sometimes noted as 120/80 mm Hg. However, this is only an average and the healthcare provider needs to consider acceptable ranges for individual clients. For example, in adults, normal blood pressure can range from 95–145/60–90 mm Hg. The healthcare provider considers the client’s baseline blood pressure and the client’s current health state in conjunction with subjective data and other objective data. For example, a blood pressure of 90/50 mm Hg may be normal for a healthy, asymptomatic 20-year-old adult.
Factors that influence blood pressure include age, sex, ethnicity, weight, exercise, emotions/stress, pregnancy, and diurnal rhythm as well as medication use and disease processes.
- The general pattern is that blood pressure rises with age, so normal variations tend to be higher for older adults.
- Blood pressure is similar in childhood for males and females. After puberty, females have lower blood pressure than males, whereas after menopause females have higher blood pressure than males.
- Research has revealed that ethnicity may be a predictor of blood pressure, but this causation is not necessarily biological, but rather sociocultural. When determining risk for high blood pressure, it is important to consider ethnicity as a contributing factor.
- The diurnal cycle influences blood pressure to be lower in the morning and increase throughout the day until early evening. Try it out: take your blood pressure when you wake up in the morning and then again in late afternoon, and note the difference. This is one reason why healthcare providers document the time a client’s blood pressure is taken.
- Blood pressure can be higher in people who are obese because the heart has to work harder to perfuse the body’s tissues.
- The sympathetic nervous system is stimulated by exercise, stress, anxiety, pain, anger, and fear, which increases blood pressure. Blood pressure returns to baseline within five minutes of rest following activity. Try it out. Have a peer take your blood pressure. Then, run on the spot or do some other cardiac activity for five minutes. Have the peer take your blood pressure again, and then lie down and rest for five minutes. Take the blood pressure again. Note the changes.
- Blood pressure varies throughout the duration of pregnancy. It decreases about halfway through the first trimester until mid-pregnancy due to progesterone effects that relax the walls of blood vessels, causing decreased peripheral vascular resistance. It returns to pre-pregnancy values toward the end of pregnancy.
Points to Consider
White coat syndrome refers to elevated blood pressure due to nervousness or anxiety when clients have their blood pressure taken by a healthcare provider. This occurs in approximately 20% of clients. Key message: have the client take their blood pressure at home with an automatic home blood pressure cuff and compare the findings. Alternatively, you can ask the client to sit quietly and leave the room while an automatic cuff takes a client’s blood pressure. The automatic cuff can be programmed to take three measurements and the blood pressure documented is an average of the three readings.


9.7: Blood Agar Plate Media, BAP
- Demonstrate proficiency in aseptic techniques required for the proper inoculation and handling of blood agar plates.
- Differentiate hemolytic patterns (alpha, beta, and gamma) exhibited by microorganisms when grown on blood agar.
- Understand the clinical relevance of blood agar media in microbiology, connecting laboratory findings to real-world applications such as the diagnosis of infectious diseases.
Blood Agar
Blood agar is an enriched medium used for the isolation and cultivation of fastidious bacteria . Fastidious organisms require specific nutrients and don’t grow well on general media like nutrient agar. Blood agar is prepared from a tryptic soy agar base enriched with 5% sheep blood (Fig.1).
Several species of gram-positive cocci produce exotoxins called hemolysins , which are able to destroy red blood cells (RBCs) and hemoglobin. Blood agar can differentiate bacteria based on their hemolytic properties. The three major types of hemolysins are beta hemolysis (β), alpha hemolysis (α), and gamma hemolysis (γ).
Beta hemolysis is the complete lysis of red blood cells. It is defined by a clear zone of hemolysis surrounding the colonies grown on a blood agar plate (Fig.2). The clear zone is a result of the complete denaturation of the hemoglobin protein. β-hemolytic bacteria include group A streptococci like Streptococcus pyogenes . Infections caused by S. pyogenes include strep throat, scarlet fever, bacteremia, pneumonia, necrotizing fasciitis, myonecrosis, and Streptococcal Toxic Shock Syndrome (StrepTSS)
Figure 2: Clearing of blood agar by beta-hemolytic Streptococcus pyogenes .
Alpha hemolysis is the partial destruction of RBCs. Microscopic inspection of alpha-hemolyzed RBCs shows that the cell membrane is intact. During α-hemolysis, hemoglobin is reduced to methemoglobin which produces a greenish discoloration of the agar around the colonies (Fig.3). Some of the α-hemolytic species are a part of the human normal flora (e.g., Escherichia coli ), but some species like Streptococcus pneumonia are pathogenic.
Figure 3: Normal upper respiratory biota demonstrating alpha-hemolytic activity. The greenish discoloration is a result of incomplete red blood cell lysis.
Gamma hemolysis is a lack of hemolytic activity and results in simple growth with no change to the medium present (Fig.4). Enterococcus faecalis , a common human urinary tract pathogen, frequently exhibits gamma hemolytic activity.
Figure 4: This streak plate of Enterococcus faecalis on blood agar illustrates no hemolytic activity.
The Diagnosis of Strep Throat
Streptococcus pyogenes is a potentially pathogenic bacterium known to cause strep throat, scarlet fever, pneumonia, bacteremia, and Streptococcal Toxic Shock Syndrome. An identifiable characteristic of S. pyogenes is beta-hemolysis, or complete destruction of red blood cells. This results in a clear zone around S. pyogenes grown on blood agar. When a patient is showing symptoms of strep throat, a throat swap is taken. The throat swap is then used to inoculate blood agar media. If results a clear zone around the bacterial growth, there is a high probability S. pyogenes is the cause of infection. Therefore, if a culture from a throat swab shows beta hemolysis, there is high likelihood that patient is infected has strep throat.
Figure 5. The image on the left depicts tonsillitis, which is a common symptom of strep throat. The image on the right depicts S. pyogenes colonies on blood agar. The clear zones around the bacterial growth indicate beta hemolysis. Throat swaps from a patient with strep throat will have similar results.
Laboratory Instructions
- On the bottom of your blood agar plate, use a sharpie to divide the plate into three sections.
- Label the plate with your name/group name, date, course section, species initials, and plate type (e.g., blood).
- With a sterile cotton swab, aseptically inoculate each section of the plate with the corresponding bacterial species. Make sure to use a new cotton swab with each bacterial species.
- Seal the plate with parafilm.
- Invert the petri plate and incubate for 24 hours at 37 °C.
- Observe, record, and interpret results.
Resources
- Rebecca Buxton. 2005. Blood agar plates and hemolysis protocols. Web. 1 October 2016 Rebecca Buxton. 2005. Blood agar plates and hemolysis protocols. Web. 1 October 2016 http://www.asmscience.org/content/education/protocol/protocol.2885
- Stevens, D. L., & Bryant, A. E. (2016). Severe group A streptococcal infections. https://www.ncbi.nlm.nih.gov/books/NBK333425/
Attributions
- 22.4: Blood Agar Plates (BAP) is shared under a CC BY license and was authored, remixed, and/or curated by Kelly C. Burke .
Figure 5 Modified from:
- "S. Pyogenes Infection (Sketch).jpg" by Sam-Bullo, Wikimedia Commons is licensed under CC BY 4.0
- "Streptococcus pyogenes agar sangre.jpg" by Micronerdbox , Wikimedia Commons is licensed under CC BY 2.0


Chapter 10: Transition Metal Complexes and Coordination Compounds
Introduction
In this chapter, we explore the concept of coordination chemistry . Coordination complexes and complex ions are fascinating chemical species formed when a central transition metal atom or ion bonds to surrounding molecules or ions called ligands . These ligands act as Lewis Acids who donate electron pairs to the metal, creating a structure with unique geometric and electronic properties. The versatility of coordination complexes stems from their diverse bonding arrangements, variable oxidation states, and the ability of transition metals to accommodate different numbers of ligands.
These compounds are integral to many natural and technological processes. The vivid colors of many transition metal complexes also find use in pigments, dyes, and displays. Additionally, their ability to bind selectively to certain ions or molecules makes them valuable in analytical chemistry, medicine, and environmental remediation.
Figure 10.1: Glazed ceramic Sphinx of Amenhotep III, c. 1390-1352 B.C.E. The beautiful blue color of this glaze technique is due to copper-based coordination compounds that have structural properties allowing for the absorption, reflection, and emission of visible electromagnetic radiation (CC 1.0: Metroplitan Museum of Modern Art via WikiMedia Commons )
In biology, coordination complexes are essential for life; hemoglobin, for instance, uses an iron-centered complex to transport oxygen in the bloodstream. In industry, they are crucial for catalysis, such as in the production of plastics and pharmaceuticals. In modern materials science, coordination compounds are used in catalysts, dyes, and even medical imaging agents like MRI contrast media. Studying coordination complexes reveals the behaviors of the often-ignored transition metals, which opens doors to innovations in materials science, medicine, and technology.
-
- 10.1: Properties of Transition Metals
- The transition metals are elements with partially filled d orbitals, located in the d-block of the periodic table. The reactivity of the transition elements varies widely from very active metals such as scandium and iron to almost inert elements, such as the platinum metals. The type of chemistry used in the isolation of the elements from their ores depends upon the concentration of the element in its ore and the difficulty of reducing ions of the elements to the metals.
-
- 10.3: Ligands and Coordinate Bonds
- Crystal field theory treats interactions between the electrons on the metal and the ligands as a simple electrostatic effect. The presence of the ligands near the metal ion changes the energies of the metal d orbitals relative to their energies in the free ion. Both the color and the magnetic properties of a complex can be attributed to this crystal field splitting. The magnitude of the splitting depends on the nature of the ligands bonded to the metal.
-
- 10.4: Molecular Geometry and Isomerization
- Two compounds that have the same formula and the same connectivity do not always have the same shape. There are two reasons why this may happen. In one case, the molecule may be flexible, so that it can twist into different shapes via rotation around individual sigma bonds. This phenomenon is called conformation, and it is covered in a different chapter. The second case occurs when two molecules appear to be connected the same way on paper, but are connected in two different ways in three dimens
-
- 10.5: Metal Complexes in Living Organisms
- In this section, we describe several systems that illustrate the roles transition metals play in biological systems. Our goal is for you to understand why the chemical properties of these elements make them essential for life. We begin with a discussion of the strategies organisms use to extract transition metals from their environment.


13.4: Spanish Grammar in Context- Passive Voice
Passive Voice
Voice refers to the relationship between the subject and the verb in a sentence. A sentence is said to be in the active voice if the subject is performing the action of the verb. For example, Juan leyó el libro . In this sentence, the subject ( Juan ) performs the action of reading the book. Active subjects are called agents .
The passive voice, on the other hand, refers to a sentence in which the subject receives the action. In other words, the subject is passive, or acted upon by the agent. For example: El libro fue leído por Juan . In this sentence, the book receives the action performed by Juan , the agent.
There are two types of passive voice constructions:
- ser + past participle of verb (+ por + agent)
- se + 3rd person of verb
Formation
Passives with ser
Conjugated form of
ser
+
past participle of main verb
(+
por
+
agent
)
Note that the past participle always agrees in number and gender with the subject. In the example below
obras
is feminine and plural so the participle appears in the feminine plural form
realizadas
.
Estas obras fueron realizadas por un artista mexicano. These works were made by a Mexican artist.
The agent, when mentioned, is usually preceded by por . However, the agent is not necessarily always expressed.
Se refieren a una persona que a la mejor de origen hispano o mexicano, que ya fue, fue criada en Estados Unidos. They refer to a person that maybe is of Hispanic or Mexican origins, that was, was raised in the United States.Passives with se
se + 3rd person verb (singular or plural depending on the subject)
The verb is conjugated either in 3rd person singular or plural depending on the subject.
Uses
The passive voice places the focus on the object of the verb rather than the subject. Compare the two examples below. In the first sentence, Luis doesn’t want to focus on or even mention who raised him (the agent) so he uses a passive construction. In the second sentence, his parents play an active role in the narrative.
Creo que fui criado para adaptarme a cualquier circunstancia. I think I was raised to adapt to any circumstance.Creo que mis padres me criaron para adaptarme a cualquier circunstancia. I think my parents raised me to adapt to any circumstance.
The passive voice draws attention to an event without necessarily mentioning who is responsible for it. In the sentence below, Stephen doesn’t mention who sent him to Brazil; we only know that he was sent there.
Yo fui a Brasil, fui asignado a ir a una parte al sur de Brasil. I went to Brazil, I was assigned to go to a region in the South of Brazil.


9.17: Performance Objectives and Measurements
- Compare various performance objectives and measurements
A performance metric measures an organization’s behavior, activities, and performance. It should support a range of stakeholder needs from customers to shareholders to employees. While traditionally many metrics are finance based, inwardly focusing on the performance of the organization, metrics may also focus on the performance against customer requirements and value. In project management, performance metrics are used to assess the health of the project and consist of the measuring of seven criteria: safety, time, cost, resources, scope, quality, and actions.
A criticism of performance metrics is that when the value of information is computed using mathematical methods, it shows that even performance metrics professionals choose measures that have little value. This is referred to as the “measurement inversion”. For example, metrics seem to emphasize what organizations find immediately measurable—even if those are low value—and tend to ignore high value measurements simply because they seem harder to measure (whether they are or not).
To correct for the measurement inversion other methods, like applied information economics, introduce the “value of information analysis” step in the process so that metrics focus on high-value measures. Organizations where this has been applied find that they define completely different metrics than they otherwise would have and, often, fewer metrics. For projects, the effort to collect a metric has to be weighed against its value as projects are temporary endeavors performed with finite resources.
There are a variety of ways in which organizations may react to results. This may be to trigger specific activity relating to performance, such as an improvement plan, or to use the data merely for statistical information. Often closely tied in with outputs, performance metrics should usually encourage improvement, effectiveness, and appropriate levels of control.
Contributors and Attributions
- Performance metric. Provided by : Wikipedia. Located at : https://en.wikipedia.org/wiki/Performance_metric . License : CC BY-SA: Attribution-ShareAlike


27.2D: Implantation
Implantation is the very early stage of pregnancy at which the embryo adheres to the wall of the uterus and begins to form the placenta.
- Outline the process of implantation in pregnancy
Key Points
- At this stage of prenatal development the embryo is a blastocyst. In humans, implantation of a fertilized ovum occurs between 6 to 12 days after ovulation.
- In preparation for implantation, the blastocyst sheds its outside layer, the zona pellucida, and is replaced by a layer of underlying cells called the trophoblast. The trophoblast will give rise to the placenta after implantation.
- During implantation, the trophoblast differentiates into two distinct layers: the inner cytotrophoblast, and the outer syncytiotrophoblast. The syncytiotrophoblast then implants the blastocyst into the endometrium by forming finger-like projections into the uterine wall called chorionic villi.
Key Terms
- endometrium : The mucous membrane that lines the uterus in mammals and in which fertilized eggs are implanted.
- trophoblast : The membrane of cells that forms the wall of a blastocyst during early pregnancy and provides nutrients to the embryo and later develops into part of the placenta.
- human chorionic gonadotropin (hCG) : In molecular biology, human chorionic gonadotropin (hCG) is a hormone produced during pregnancy that is made by the developing placenta after conception, and later by the placental component.
- implantation : The embedding of the blastocyst to the uterine wall.
Implantation is the very early stage of pregnancy during which the embryo embeds into the wall of the uterus. At this stage of prenatal development, the embryo is a blastocyst.
It is by this adhesion that the fetus receives oxygen and nutrients from the mother to be able to grow. In humans, implantation of a blastocyst occurs between 6 to 12 days after ovulation.
In preparation for implantation, the blastocyst sheds its outside layer, the zona pellucida, which binds sperm during fertilization. The zona pellucida degenerates and decomposes, and is replaced by a layer of underlying cells called the trophoblast.
The trophoblast will give rise to the placenta after implantation. During implantation, the trophoblast differentiates into two distinct layers: the inner cytotrophoblast, and the outer syncytiotrophoblast.
Chorionic villi : During implantation, extensions of the trophoblast, the syncytiotrophoblasts, embed within the endometrium and form chorionic villi.
The syncytiotrophoblast then implants the blastocyst into the endometrium of the uterus by forming finger-like projections into the uterine wall called chorionic villi. The chorionic villi grow outwards until they come into contact with the maternal blood supply.
The chorionic villi will be the border between maternal and fetal blood during the pregnancy, and the location of gas and nutrient exchange between the fetus and the mother. The creation of chorionic villi is assisted by hydrolytic enzymes that erode the uterine epithelium.
The syncytiotrophoblast also produces human chorionic gonadotropin (hCG), a hormone that notifies the mother’s body that she is pregnant and prevents menstruation by sustaining the function of the progesterone-producing corpus luteum within the ovary.
Human chorionic gonadotropin is the hormone that is detected by pregnancy tests, as it is found in the maternal bloodstream and urine.
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- embryonic disk. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/embryonic%20disk . License : CC BY-SA: Attribution-ShareAlike
- blastocyst. Provided by : Wiktionary. Located at : en.wiktionary.org/wiki/blastocyst . License : CC BY-SA: Attribution-ShareAlike
- gastrulation. Provided by : Wiktionary. Located at : en.wiktionary.org/wiki/gastrulation . License : CC BY-SA: Attribution-ShareAlike
- Human Fertilization. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/File:Human_Fertilization.png . License : CC BY-SA: Attribution-ShareAlike
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- Blastocyst English. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/File:Blastocyst_English.svg . License : CC BY-SA: Attribution-ShareAlike
- Human embryogenesis. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Human_e...23Implantation . License : CC BY-SA: Attribution-ShareAlike
- Implantation (human embryo). Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Implantation_(human_embryo) . License : CC BY-SA: Attribution-ShareAlike
- endometrium. Provided by : Wiktionary. Located at : en.wiktionary.org/wiki/endometrium . License : CC BY-SA: Attribution-ShareAlike
- implantation. Provided by : Wiktionary. Located at : en.wiktionary.org/wiki/implantation . License : CC BY-SA: Attribution-ShareAlike
- human chorionic gonadotropin (hCG). Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/human%2...tropin%20(hCG) . License : CC BY-SA: Attribution-ShareAlike
- trophoblast. Provided by : Wiktionary. Located at : en.wiktionary.org/wiki/trophoblast . License : CC BY-SA: Attribution-ShareAlike
- Human Fertilization. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/File:Human_Fertilization.png . License : CC BY-SA: Attribution-ShareAlike
- Gray9. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/File:Gray9.png . License : Public Domain: No Known Copyright
- Blastocyst English. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/File:Blastocyst_English.svg . License : CC BY-SA: Attribution-ShareAlike
- Gray36. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/File:Gray36.png . License : Public Domain: No Known Copyright


15.3: Exam 3 Information (Final Exam)
Exam 3:
Final Exam
Overview
The questions in this exam are “deep-thinking” questions designed to cultivate critical thinking based on what you have learned in the course up to this point. Each question will be worth 25 points (25 points x 3 questions = 75 points total).
You will be asked to write a response to 3 of the 6 possible questions below. The specific three questions you will address will be chosen randomly based on the first letter of your last name. This will be announced on the course home page on the day the exam is due, so it is best to have outlines and/or full responses prepared in advance for all the questions.
Feel free to prepare your answers in advance to save you time on Exam day.
- As you review these questions, you are permitted to draft your answers ahead of time, as well as use reputable, high-quality resources outside of the textbook. Please cite any additional sources you used in your research.
Instructions
See the Schedule of Work for date of availability and due date.
You will be asked to write a response to 3 of the 6 possible questions below. The specific three questions you will address will be chosen randomly based on the first letter of your last name. This will be announced on the course home page on the day the exam is due, so it is best to have outlines and/or full responses prepared in advance for all the questions.
- Responses should be 3 – 4 paragraphs in length (where each paragraph consists of at least 5 – 6 sentences).
- Your response must directly answer the question posed. You will not be permitted to use tactics such as answering the question with more questions.
- All of your work should be in your own words, with no direct quotes from other sources.
- Do not include the original question in your document, because the plagiarism checker will detect this. Please aim for < 25% similarity to other sources in the plagiarism checker when you submit your document.
- Complete sentences with correct spelling and grammar will be expected.
Exam Questions
- You are applying for a summer internship at the Nevada Geology Survey. At the interview, your future employer asks you to take a look at this simple cross section of Death Valley. What information can be derived from this cross section with regard to the formation of Death Valley? Include some discussion of the type of faulting present and any evidence you used to determine this. In addition, please address the larger “big-picture” tectonic setting that was at work in the formation of this valley, based on what you can conclude from the cross section, as well as what you have learned about plate tectonics and structural geology.
- You are hired as a consultant for the Center for Biological Diversity, which is concerned about a new, large housing development that will be situated adjacent to a nearby river and riparian area. The proposed development will draw water from its own drilled groundwater wells (approximately 10), rather than the public water supply. The cross section below shows the current water table in the river, the unconfined aquifer, and in a rancher’s nearby private well that he uses to provide water for his stock tank (the water table is represented by the dotted black line). Describe the predicted effects the proposed development and well field may have on the height of the water table, the rancher’s private well, and water level in the river. Use colored pencils to draw your predicted outcome with regard to changes to the water table in the figure below, including any cone(s) of depression that may result from groundwater withdrawal in new or existing wells. Include in your response some discussion as to why maintaining the current (pre-development) level of the water table is critical to the ecosystem.
- Recent and devastating forest fires in a national forest have removed a significant amount of vegetation across several hundred square kilometers around the perimeter of a steep canyon and popular recreation area in the Southwest. The climate models for the coming summer monsoon are predicting above-average monsoon precipitation. As a land manager for the Forest Service, you quickly realize that the canyon and nearby recreation area may become vulnerable to several geological and hydrological hazards. What specific hazards might the canyon experience during the coming summer, if the climate models are correct? Explain why you think the canyon is vulnerable to these specific hazards. What steps can you take to keep the public safe and avoid fatalities during the summer tourist season?
- You have been hired as a tour guide for the American Museum of Natural History in New York City. The museum has recently acquired a piece of the Acasta Gneiss, dated at over 4 billion years old, and found in the Northwest Territories, Canada. The people in your tour are always asking the same questions: How can scientists figure out how old this rock is? What is “gneiss?” Why is this type of rock rare on Earth’s surface? Why is this continental rock so old compared to oceanic rocks? Being the professional that you are, you are able to answer each of their questions with confidence and clarity.What do you tell them?
- You are serving on the Intergovernmental Panel on Climate Change and are preparing an updated publication that will inform all levels of government and the public on the state of the global climate. As a key committee member, how would you summarize for the public the main drivers (causes) of climate warming? What scientific measurements have been made (either directly or by proxy) that have led to the conclusion that Earth is indeed warming? What recommendations would you make for changing habits or policy, on either a governmental or personal level (or both)? Include some discussion on the biggest concerns with regard to the effects of global warming on Earth’s systems.
- You are taking relatives to see the Grand Canyon for the very first time. Knowing that you have recently completed a rigorous course in geology, naturally they have lots of questions. At the Visitor Center, they spot the following display of all the rock formations in the canyon (see the key in the image caption). Your relatives ask you specific questions: What type of rocks are predominant in the canyon (igneous, metamorphic, sedimentary)? Which rock layer is the oldest and which is the youngest (and how do you know)? Relatively speaking, when did the Colorado River start carving out the canyon (after the deposition of which layer)? What caused the canyon to form? You feel compelled to brag a little about your new knowledge. Tell them everything you know
Grading Rubric
Answers are worth 25 points each (3 answers x 25 points each = 75 points total). Points will be deducted for spelling errors, grammatical errors, or insufficient length. Points will be awarded for each answer according to the following rubric:
25 points : Answer addressed the question and illustrated your efforts at providing an accurate, in-depth, and thoughtful response. Answer was at least 3 – 4 paragraphs and contained few to no spelling or grammar errors.
20 points : Answer addressed the question and was an appropriate length, but may be lacking sufficient detail or contains a few inaccuracies. Significant effort was shown in the crafting of your response, despite the inaccuracies. Answer may contain a minor amount of spelling or grammar errors.
15 points : Answer was the appropriate length, but contained quite a few inaccuracies. Response seemed hurried or lacked depth or detail.
10 points : Answer did not adequately address the question. Response was hurried and showed lack of detail and knowledge on the subject. Length was insufficient.
5 points : Answer was insufficient in length (less than 1 – 2 paragraphs) and did not address the question with any effort or detail. Knowledge on the subject was not demonstrated. 0 points: Response was not provided.


7.2.24: Flashcards (Usable with Workarounds)
Query \(\PageIndex{1}\)
Overall Usability
Usable with Workarounds:
- The activity requires significant adjustments by content authors.
Important Reminders
Some users may find the automatic sliding to the next flashcard distracting or disruptive and may require an alternative version of the activity. Provide instructions for users describing that after answering a question the activity automatically moves to the next flashcard.
Use best practices for content authoring, including:
- Add alt-text descriptions up to 150 characters for meaningful images
- use good color contrast for meaningful visual information in images.
Users who require good color contrast may need to be provided with an alternative activity.
Users who require magnification up to 400% may need to be provided with an alternative activity.
Visible Indication of Focus
The activity buttons and form fields have a visible indication of focus.
Color Contrast
The visible indication of focus does not have good contrast. Users who require a visible indication of focus with more contrast may use assistive technology. Most of the activity text, buttons, and form fields do not have good color contrast.
Keyboard Usability
The activity is usable with the keyboard. H5P does not provide an option to stop the flashcards from automatically advancing after a user answers a question. Users should be informed that Tip buttons come after the Check answer buttons in the page reading order.
No Keyboard Traps
There are no keyboard traps.
Magnification
Content magnifies up to 200% using browser settings without loss of content or functionality. The Correct and Incorrect text overlaps longer answer text when magnified up to 400%. The Check answer button text is not visible at 400% and the tooltip for the button does not magnify.
An alternative version of the content should be included that supports magnification up to 400% without requiring horizontal scrolling to view content and interact with content.
Usability with Screen Reading Software
The activity is usable with screen reading software. In Results, H5P does not include accessible labels for the icons that identify correct and incorrect answers. Instructions should be provided to users that incorrect answers are labeled with the text "A:" and include the correct answer, while correct answers are only labeled with the text "A:".


4.1: Function Definition
A function is a rule that assigns to each element in the set of input values (the domain), one and only one element in the set of output values (the range).
Determine if each of the following equations are functions:
- \(y = x^2 + 1\)
- \(y^2 = x + 1\)
Solution
- To see the result of this equation, let x = 3.
\(\begin{aligned} y &= x^2 + 1 \\ y &= 3^2 + 1 \\ y &= 9 + 1 \\ y &= 10\end{aligned}\)
Any value entered for \(x\) yields exactly one value for \(y\).
There is only one solution for \(y\), \(y = 10\).
\(y = x^2 + 1\) is a function!
- To see the result of this equation, once again let \(x = 3\).
\(\begin{aligned} y^2 &= x + 1 \\ y^ 2 &= 3 + 1 = 4 \\ y &= \sqrt{4 } \\ y &= 2 \text{ or } y = −2\end{aligned}\)
Any value entered for \(x\) will not yield exactly one value for \(y\). There are two solutions for \(y\), \(y = 2\) and \(y = −2\).
\(y^2 = x + 1\) is NOT a function!


1.1: What is Communication?
When reading George Bernard Shaw’s words above, most people can easily identify with this sentiment. Undoubtedly, many individuals have experienced the pains and frustration inherent with instances of miscommunication, which is likely the reason people so easily recognize the humor inherent in his statement.
In fact, it may prove easier to identify and define elements of miscommunication than to identify and define the process of communication. Communicators can face many challenges, like using the wrong word for the wrong audience, failing to use the appropriate tone for the intended message, or leaving out pertinent information. Sadly, individuals may find it easier to mis communicate than to simply get their message across to their intended audience correctly and efficiently the first time.


14.6: Mutual Inductance
A device specifically designed to produce the effect of mutual inductance between two or more coils is called a transformer .
The device shown in the above photograph is a kind of transformer, with two concentric wire coils. It is actually intended as a precision standard unit for mutual inductance, but for the purposes of illustrating what the essence of a transformer is, it will suffice. The two wire coils can be distinguished from each other by color: the bulk of the tube’s length is wrapped in green-insulated wire (the first coil) while the second coil (wire with bronze-colored insulation) stands in the middle of the tube’s length. The wire ends run down to connection terminals at the bottom of the unit. Most transformer units are not built with their wire coils exposed like this.
Because magnetically-induced voltage only happens when the magnetic field flux is changing in strength relative to the wire, mutual inductance between two coils can only happen with alternating (changing—AC) voltage, and not with direct (steady—DC) voltage. The only applications for mutual inductance in a DC system is where some means is available to switch power on and off to the coil (thus creating a pulsing DC voltage), the induced voltage peaking at every pulse.
A very useful property of transformers is the ability to transform voltage and current levels according to a simple ratio, determined by the ratio of input and output coil turns. If the energized coil of a transformer is energized by an AC voltage, the amount of AC voltage induced in the unpowered coil will be equal to the input voltage multiplied by the ratio of output to input wire turns in the coils. Conversely, the current through the windings of the output coil compared to the input coil will follow the opposite ratio: if the voltage is increased from input coil to output coil, the current will be decreased by the same proportion. This action of the transformer is analogous to that of mechanical gear, belt sheave, or chain sprocket ratios:
A transformer designed to output more voltage than it takes in across the input coil is called a “step-up” transformer, while one designed to do the opposite is called a “step-down,” in reference to the transformation of voltage that takes place. The current through each respective coil, of course, follows the exact opposite proportion.
Review
- Mutual inductance is where the magnetic field generated by a coil of wire induces voltage in an adjacent coil of wire.
- A transformer is a device constructed of two or more coils in close proximity to each other, with the express purpose of creating a condition of mutual inductance between the coils.
- Transformers only work with changing voltages, not steady voltages. Thus, they may be classified as an AC device and not a DC device.


2.4: Population Is Dynamic
Although the world’s population is still growing, the overall growth has slowed and the growth has become very uneven. Some places are still growing very rapidly. Others are growing much more slowly and some are shrinking in terms of population. We can compare differences between places using a series of different rates. Rates are ratios that divide the occurrence of a phenomenon with the population hosting the phenomenon. For example, crude birth rate is calculated as the number of births per 1000 people in a particular place in a particular year. The crude death rate is similar. It is calculated as deaths per 1000 people in a particular place in a particular year. These numbers can be used to compare places, but they have great limitations.
 Just because the average woman in a country has 2.3 children tells you nothing about a particular woman. The ecological fallacy is the idea that aggregated data tell you anything about individuals. It does not because it cannot. Once the data are lumped together, they lose their individual characteristics.
The rates do not necessarily relate to one another, either. The crude birth rate doesn’t tell you anything about the average number of children born per woman, at what stage in their lives women tend to have children, etc. The crude death rates don’t separate deaths of elderly people from deaths of infants. High rates of death are often found in developed societies; in many ways it’s a sign of development, since developed countries tend to have older populations. A high rate of infant mortality (children under 1 year of age) is a near-universal sign of underdevelopment. The countries with the highest crude birth rates tend to be low income ( Figure 2.8 ).
The crude death rate is more nuanced ( Figure 2.9 ). Some countries on the map, for example, Chad, have a high crude death rate due to a high rate of infant and child mortality. Russia, on the other hand, has a rapidly aging population and a partially collapsed social security network.
The replacement level of a population refers to the number of births that are necessary to offset deaths. This is often referred to in terms of average fertility of women. In modern societies, on average, women need to produce 2.1 children in a lifetime to keep a place demographically stable. This number is derived by counting a mother and her partner, and accounts for those who never reproduce.
Places with a fertility rate below 2.1 will shrink over time. Those places above that will grow, and those well above that will grow quickly ( Figure 2.10 ). The preceding graphic demonstrates that in the same way that many places are growing very rapidly, many places are at or below replacement. The United States is below replacement. It is demographically buoyed by immigration.
What kinds of places are growing fastest? These are places that are poor or economically or politically unstable. This may seem counterintuitive. Why would people have children in places that are already so poor? Remember that individual families have children. Children can seem like a mechanism for surviving bad situations. What kinds of places are declining? This is more complicated, but in general the more educated and empowered the female population is, the lower the birth rate. This isn’t a perfect, linear relationship, but it’s useful as a start. Why is there so much variability? Because places matter. Uganda has a government advocating population growth, while Afghanistan and Somalia have little governance at all. Russia and Australia have similar fertility rates, and few other similarities.
General measurements of population are useful, but often if is useful to know the age and gender structure of a population. This is shown using a population pyramid. A population pyramid breaks the population into groups sorted by age ranges, called cohorts , as well as by sex. The resulting shape tells you a great deal about the population dynamic of the country. If the shape is actually a pyramid, then the country has a high birth rate and a high death rate. Countries with stable populations look like a column. Some countries even have their greatest population in the older cohorts with comparably few young people. Figure 2.11 shows some examples of current populations. Some examples of estimated future populations are shown in Figure 2.12 .
First, it is important that you understand that all these numbers are estimates. Current population numbers are good enough for general comparison. As you can see, the differences between places becomes more pronounced as we look toward the future. The world population increases by over two billion people, but what is interesting are the shifting dynamics between countries. China shrinks by more than 30 million, the US grows by 64 million, and Nigera poor Saharan countrygrows by 52 million, more than double its current size! One of the most useful measures of population is doubling time , which is how much time it would take at current levels of population growth for a population to double. According to Figure 2.2 , most of human history saw very slow growth with doubling times measured in centuries. During the 19 th and 20 th centuries, doubling time at the global level fell to as short as 35 years.
This has numerous implications. At the global level, those extra billions will need food and water, houses and clothing. That is to say that they will require resources. They will also have desires that require even more materials and energy expenditure. In places like Niger, this will be very difficult, if not impossible, to meet.
In places like China, a completely different problem presents itself. These populations are both shrinking and aging. Life expectancy , the average lifespan in a country, has been increasing for decades in developed and some developing countries. At the same time, birth rates have fallen for a variety of reasons. This means that as time passes, the elderly portion of the population has grown. Many countries will see their populations age until large percentages will be unable to work. Societies for the past several centuries have prepared themselves for population growth, and much of modern society is predicated on it. Population growth is what has paid for social security for the elderly. Few places have prepared themselves for fewer workers in the future (although robotics may address this problem). This change will not happen at once, but the effects will be tremendous.
Another characteristic that must be acknowledged is population momentum . When much of your population is older than 45, it isn’t reasonable to expect that population will continue to grow quickly. Countries with young populations should expect that their populations will grow when the large pool of young people have children of their own.
This map shows the tremendous differences in life expectancy from one country to another ( Figure 2.13 ). In some places, people tend to live into their ninth decade. In others, they are unlikely to make it into their sixth.
The dependency ratio is simply the number of people within a society who do not work compared to the number who do work. There are two main components of the dependency ratiochildren under 15 years old and the elderly over 65 years old, although the degree to which either group is dependent is variable ( Figures 2.14 and 2.15 ). Children need care and schooling, but generally produce little of economic value. Elderly populations can be too infirm to work and are the part of the population with the highest medical costs. Where does the wealth come from to take care of these two groups? It comes from the people working and producing wealth. If the dependency ratio is high, then each worker can be responsible for a large number of dependents and less wealth will be left for the workers.
Although the dependency ratio is used to compare places, this particular ratio can be somewhat misleading. In many less developed places, children are not dependent. They are not in school and they are employed. They are not consuming a family’s resources, but are instead contributing to them. In other places, the elderly may still be in the workplace. The dependency ratio informs decisions regarding the future. Will a country need more schools or assisted living centers. What does this mean for retirement or pensions? Perhaps more importantly, will the supply of workers increase or decrease? Comparing China, Niger, and the U.S. shows you that different places have different options and challenges.


8: Second-Order ODEs, Constant Coefficients
Reference: Boyce and DiPrima, Chapter 3
The general linear second-order differential equation with independent variable \(t\) and dependent variable \(x=x(t)\) is given by
\[\ddot{x}+p(t) \dot{x}+q(t) x=g(t), \nonumber \]
where we have used the standard physics notation \(\dot{x}=d x / d t\) and \(\ddot{x}=d^{2} x / d t^{2}\) . Herein, we assume that \(p(t)\) and \(q(t)\) are continuous functions on the time interval for which we solve Equation \ref{8.1}. A unique solution of Equation \ref{8.1} requires initial values \(x\left(t_{0}\right)=x_{0}\) and \(\dot{x}\left(t_{0}\right)=u_{0}\) . The equation with constant coefficients-on which we will devote considerable effort-assumes that \(p(t)\) and \(q(t)\) are constants, independent of time. The linear second-order ode is said to be homogeneous if \(g(t)=0\) .


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1.2.1: Paleolithic
1.2: Introduction
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2.11: Career Counseling
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- Susan Rahman, Prateek Sunder, and Dahmitra Jackson
- CC ECHO
Career Counseling is a process that helps an individual know and understand themselves, and the world of work in order to make career, educational, and life decisions. Oftentimes, this type of work is done in the college setting for students who are trying to decide on both their college and career pathways so career counselors in an academic setting have great influence on students. They are usually part of an institution's student servicesdepartment.Career Centers/Career Services support students (and sometimes alumni) in their career development process. The career development process includes self-exploration/reflection, career & major decision making, and support with everything needed to obtain post-graduation goals: resume/cover letter/interview support, internship and job search strategies, and support.
The field of career services/career counseling in higher education is deeply entrenched in white supremacy and patriarchy. The field as a whole is only beginning to consider the ways in which those in it perpetuate systemic & individualized oppression. One example of how students are counseled centers around student’s presentation of self. Many college career centers state their aim is to support their students in becoming what is often termed“professional.” Research into the use of the focus on professionalism has demonstrated that the idea of professionalism itself is a white, western, patriarchal ideal, which when employed perpetuates unequal access to opportunity for students of color (Gray, 2019).
Additionally, beyond the goals and aims of a career center, they are one of the departments on campus that has access to employers who hire students.Because of their access to employers, counselors have the opportunity to help level the playing field in a mindful and positive way.This unique role creates a huge opportunity for true student advocacy focused on dismantling systemic issues. At present, there are clear and identified hiring practices that are harmful and/or discriminatory to people of color, specifically Black individuals(Rios, 2015).
Many career centers and career counselors state that they believe in and prioritize diversity, inclusion, and equity,however, the focus is mainly on creating resources and best practices for working with diverse students. This positions these students in relation to whiteness which in and of itself keeps structures in place (Gerdman, 2017). These types of policies or advocacy statements do little to actually advocate/educate employers on how their hiring practices may be racist or discriminatory. Many in the field of career counseling, have started getting requests for access to “diverse students” (Anderson, 2020). The purpose of this may be an attempt at equity, but it also begs the question of how universities and career centers are protecting their students and ensuring those workplaces are actually inclusive, as opposed to doing further harm by sending them into environments that are at best, tokenizing,and at worst, racist and discriminatory (Dali, 2018). Decentering whiteness as the norm for gauging professionalism in students can be done intentionally by career center staff and faculty without tokenizing, if staff commits to self-reflectivity and ongoing anti-bias work (Anderson,2020).


5.8: Rhetorical Theories Paradigm
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Rhetoric is the oldest tradition of the Communication field. A good definition of rhetoric is, “any kind of human symbol use that functions in any realm—public, private, and anything in between” (Foss, Foss & Trapp, 7). Remember that one of our definitions for theory is, “a way of framing an experience or event—an effort to understand and account for something and the way it functions in the world” (Foss, Foss, & Griffin, 8). Combining these definitions allows us to understand the Rhetorical Theories Paradigm as, “a way to understand and account for the way any kind of human symbol use functions in any realm.” Scholars have historically used rhetorical theories as a way to produce and evaluate messages.
Theories of Message Production
If you have taken a public speaking course, you were likely exposed to rhetorical theories of message production. In public speaking classes students are taught methods for organizing presentations, building credibility with the audience, and making messages more entertaining, informative, and/or persuasive. You probably intuitively understand that there are effective ways for putting together messages. But, how do you know what is truly effective or ineffective? Whether you are preparing a public presentation, an advertising campaign, or trying to persuade a friend, rhetorical theories guide the ways you produce messages. Companies devote millions of dollars to produce the advertisements we see. You can bet that significant research has gone into what messages will work the best so they do not waste their money on ineffective advertising. Audience analysis, context, goals, etc., are all considered before producing and delivering these messages.
Over the centuries, Communication scholars have devoted entire careers studying what it takes to produce effective messages. Aristotle gave us his ideas of ethos (credibility), logos (logic), and pathos (emotions) as fundamental components for constructing persuasive messages. Cicero gave us the five canons of rhetoric, or the five necessary steps for putting together an effective message. In the modern era, Stephen Toulmin developed the Toulmin model as a means for constructing persuasive arguments . Toulmin’s model of message production includes a claim, grounds, warrant, backing, modal qualifier, and rebuttal. The claim is the conclusion or argument being made . The grounds are the data and facts offered to support the claim . To logically connect the grounds to the claim , a warrant is given. The backing is used to support the warrant and the qualifiers make a statement about the strength of the claim . Words such as “possible,” “certainly,” and “definitely” are examples of qualifiers. Any exception to the claim is the rebuttal. Even if you are unfamiliar with rhetorical theories of message production above, you likely have a good idea of what makes an effective message. For Toulmin, effectiveness was based on issues of practicality — to find a claim that is of interest to people and the ability to justify it. The greater understanding you have of rhetorical theories of message production, the greater potential you have for producing effective messages in a variety of contexts.
Theories of Message Evaluation
Super Bowl Sunday is a day that many people gather together to watch a big football game on television. It is also a day that many people give special attention to watching commercials. It has become a popular pastime for people to evaluate the quality of commercials shown during the Super Bowl. In fact, all of the commercials from the Super Bowl are put on the internet for people to watch and evaluate.
Many people spend a considerable amount of time discussing the effectiveness of commercials. Those who engage in these conversations are, at a basic level, engaging in message evaluation. If you make a comment about these commercials such as, “that was funny” or “that was stupid” you are using some kind of criteria to come to those conclusions. A person approaching these messages using rhetorical theories would ask “why was that funny or stupid?” In other words, what works, or doesn’t work, about certain messages?
There are many ways we can use rhetorical theories to evaluate messages. We might choose to use a feminist, an ideological, or a narrative approach to evaluate message effectiveness. For example, Kenneth Burke argues that we can evaluate messages by understanding them as a dramatic play. He contends that all messages contain acts, scenes, agents, purposes, and agencies. If you were to evaluate your relationships with your friends from this perspective, who are the agents, what is the scene, and what act of the play are you in? Jean Baudrillard states that we can evaluate messages from the perspective that messages are commodities that we exchange. Whereas, Michel Foucault asserts that we can evaluate messages by looking at how power is enacted in them. Rhetorical theories give us different “lenses” for us to understand messages. No interpretation is right or wrong. Instead, each interpretation allows us to have a more comprehensive understanding of communication.
As with message production, we are constantly in the process of evaluating messages that are sent and received by us. The greater understanding you have of rhetorical theories for both putting together and evaluating messages, the greater potential you have to be an effective communicator in a variety of contexts. For rhetorical theorists, the message is the primary focus of inquiry when approaching the study of communication.
Strengths
The primary strength of the Rhetorical Theories Paradigm is its ability to help us produce and evaluate effective messages. Rhetorical theories provide a way for us to take context into consideration when we examine messages. Unlike empirical laws theories, rhetorical theories highlight the importance of considering context as essential for understanding messages. Finally, rhetorical theories provide a way for us to foster multiple perspectives in the evaluation and construction of messages.
Weaknesses
A primary weakness of rhetorical theories comes from one of its strengths. With such an intense focus on messages, it is possible to overlook alternative interpretations of messages. Also, some theories of message evaluation are not critical enough to reveal power dynamics at work in message exchanges. Finally, rhetorical theories are often not generalizable across a variety of communication contexts. While some rhetorical theories can be generalized, rhetorical theories are most often highly contextualized.
Contributions and Affiliations
- Survey of Communication Study. Authored by : Scott T Paynton and Linda K Hahn. Provided by : Humboldt State University. Located at : en.wikibooks.org/wiki/Survey_of_Communication_Study/Preface. License : CC BY-SA: Attribution-ShareAlike


5.6: Nucleophilic Addition of Hydride - Alcohol Formation
After completing this section, you should be able to
- write the general mechanism of nucleophilic addition of the “hydride ion” in the reduction of a carbonyl group.
Reduction of Carbonyls to Alcohols Using Metal Hydrides
We saw in Alcohol's Chapter that the most common method for preparing alcohols, both in the laboratory and in living organisms, is by the reduction of carbonyl compounds. Like carbon, hydrogen can be used as a nucleophile if it is bonded to a metal in such a way that the electron density balance favors the hydrogen side. A hydrogen atom that carries a net negative charge and bears a pair of unshared electrons is called a hydride ion. How much negative charge density resides on hydrogen depends on the difference in electronegativity between hydrogen and the metal it’s bonded to.
The most common sources of the hydride anion ( - :H) are lithium aluminum hydride (LiAlH 4 ) and sodium borohydride (NaBH 4 ) . Note! The hydride anion is not present during this reaction; rather, these reagents serve as a source of hydride due to the presence of a polar metal-hydrogen bond. Also, each are capable of delivering up to 4 hydride equivalents. The reaction equation of hydride reductions are not typically balanced ( i.e. it does not specify the stoichiometry of the reagent). Because aluminum is less electronegative than boron, the Al-H bond in LiAlH 4 is more polar, thereby, making LiAlH 4 a stronger reducing agent.
Aldehydes are reduced with sodium borohydride (NaBH 4 ) to give primary alcohols, and ketones are reduced similarly to give secondary alcohols.
Carbonyl reduction occurs by a typical nucleophilic addition mechanism under basic conditions. Although the details of carbonyl-group reductions are complex, LiAlH 4 and NaBH 4 act as if they were donors of hydride ion nucleophile, : H – , and the initially formed alkoxide ion intermediate is then protonated by addition of aqueous acid. The lithium, sodium, boron and aluminum end up as soluble inorganic salts at the end of either reaction.
The reaction is effectively irreversible because the reverse process would require the expulsion of a very poor leaving group.
Mechanism for the Reduction of Carbonyls using LiAlH 4
Both NaBH 4 and LiAlH 4 act as if they were a source of hydride. The hydride anion undergoes nucleophilic addition to the carbonyl carbon to form a C-H single bond and forming a tetrahedral alkoxide ion intermediate. The alkoxide ion is subsequently converted to an alcohol by reaction with a proton source (such as water). In the LiAlH 4 reduction, the resulting alkoxide salts are insoluble and need to be hydrolyzed (with care) before the alcohol product can be isolated. In the borohydride reduction the hydroxylic solvent system achieves this hydrolysis automatically. The lithium, sodium, boron and aluminum end up as soluble inorganic salts.
Note! The reaction and the corresponding mechanism of hydride reductions of carbonyls is fairly complicated. The following mechanism has been simplified for easier understanding.
Step 1: Nucleophilic attack to form a tetrahedral alkoxide intermediate
Step 2: Protonation to form an alcohol
Properties of Hydride Sources
Two practical sources of hydride-like reactivity are the complex metal hydrides lithium aluminum hydride (LiAlH4) and sodium borohydride (NaBH4). These are both white (or near white) solids, which are prepared from lithium or sodium hydrides by reaction with aluminum or boron halides and esters. Lithium aluminum hydride is by far the most reactive of the two compounds, reacting violently with water, alcohols and other acidic groups with the evolution of hydrogen gas. The following table summarizes some important characteristics of these useful reagents.
|
Reagent |
Preferred Solvents |
Functions Reduced |
Reaction Work-up |
|---|---|---|---|
|
Sodium Borohydride
|
ethanol; aqueous ethanol
|
aldehydes to 1º-alcohols
inert to most other functional groups |
1)
simple neutralization
|
|
Lithium Aluminum Hydride
|
ether; THF
|
aldehydes to 1º-alcohols
most functional groups react |
1)
careful addition of water
|
Limitations of Hydride Reductions
A hydride addition to an asymmetric ketone has the possibility of forming a chiral carbon that is not stereospecific. Attack by the hydride can occur from either the re or the si face of an asymmetrical carbonyl, leading to a mixture of the ( S ) and ( R ) alcohols. These reactions can be made to have stereochemical control by using several different methods including stereospecific reagents, sterics, and by the affect of an enzyme during a biological reduction.
Example
As previously mentioned, a hydride reduction using LiAlH 4 or NaBH 4 has the possibility of forming R or S stereoisomers of a chiral carbon in the product. An important area of organic synthesis is developing stereoselective methods that yield only one of the possible R and S stereocenters. Stereoselective hydride reductions can be accomplished by using the reagent Diisopinocampheylchloroborane (Ipc 2 BCl). The two versions of this reagent, (+)-Ipc 2 BCl & (−)-Ipc 2 BCl, allow for either an R or S stereocenter to be created during the hydride reduction. Ipc 2 BCl was first reported in 1961 by Zweifel and Brown and is considered a pioneering work in stereoselective synthesis using boranes. Herbert Charles Brown (1912-2004) was an American chemist who received the Nobel Prize in Chemistry in 1979 for his work with organoboranes.
Ipc 2 BCl allows for stereoselectivity by changing the mechanism of the hydride reduction and introducing sterics to the reaction. Asymmertric carbonyls which have a sterically large substituent (R L ) and a sterically small substituent (R S ) will have a preferred orientation during this reaction causing a particular stereoisomer to be formed.
Stereochemical control during a synthesis is important because a particular stereoisomer is usually the target molecular. This is particularly true in the synthesis of pharmaceuticals, where one stereoisomer often has different biological properties and another. An example of this is the drug Fluoxetine (Prozac), which was shown to have superior biological properties when the R isomer of its single chiral carbon was tested. Fluoxetine is an antidepressant given FDA approval in 1987. in 2010, over 24.4 million prescriptions for fluoxetine were filled in the United States alone. Currently, there are many different synthesis pathways to Fluoxetine. A fragment of one pathway is shown below which uses the two Ipc 2 BCl versions to synthesis both the R and S enantiomers of Fluoxetine.
Please draw the products of the reaction of the following substrates with LAH:
a- 2-butanone b-butanal
- Answer
-
Draw the structure of the molecule which must be reacted to produce the product.
- Answer
-
Deuterium oxide (D 2 O) is a form of water where the hydrogens have been replaced by deuteriums. For the following LiAlH 4 reduction the water typically used has been replaced by deuterium oxide. Please draw the product of the reaction and place the deuterium in the proper location. Hint! Look at the mechanism of the reaction.
- Answer
-


17.7.0: Review Questions
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- Last updated
- Save as PDF
Review Questions
1 .
A nurse is teaching a patient with a nutritional deficit about nutrient-dense foods. What nutrient provides the most energy per gram of nutrient?
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carbohydrates
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fats
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protein
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fiber
2 .
A nurse is caring for an older adult patient who is dehydrated. The nurse understands that the majority of water in the human body is found where?
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inside the body cells
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in the vascular system
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in interstitial fluids
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in the urinary tract
3 .
A nurse is reviewing a patient’s medication list and notes the patient takes vitamin D tablets once a day. What does the nurse know is true about vitamin D?
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found naturally in many foods
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found only in animal products
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absorbed through direct sunlight
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a trace mineral
4 .
A nurse in long-term care is reviewing charts for weight loss trends. Which patient is most at risk for developing malnutrition?
| Patient | BMI | Weight Change |
| Patient A | 25 | Gained 5 pounds in twelve months |
| Patient B | 20 | Lost 6 pounds in twelve months |
| Patient C | 18.5 | Lost 10 pounds in six months |
| Patient D | 16 | Gained 2 pounds in six months |
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Patient A
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Patient B
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Patient C
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Patient D
5 .
A nurse is working with patients in a public health clinic and is assessing for food insecurity in a local immigrant population. What observation would be most concerning for food insecurity?
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an immigrant woman applying for SNAP and WIC benefits
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an immigrant man who is unable to find foods specific to the culture
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an immigrant couple without personal transportation
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an immigrant child who does not live near a grocery store
6 .
A nurse is working with a patient on implementing healthy dietary patterns. The patient decides to develop a healthy weekly menu. What response by the patient indicates understanding of the nutrition guidelines?
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“RDA values tell me the daily intake for nutrients to guide meal planning.”
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“Proteins are the most important nutrient group.”
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“I should eat the same number of calories at every meal.”
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“I should avoid all simple carbohydrates.”
7 .
A nurse is teaching about nutrition during pregnancy and lactation. What foods would be the healthiest option to meet nutritional goals during this time?
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whole milk and red meat
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rice and beans
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eggs and low-fat dairy
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fresh fruits and fruit juices
8 .
A home health nurse is visiting a patient with multiple chronic diseases. The patient is experiencing unintentional weight loss. The nurse considers the role of nutrition in chronic illness. What conditions will not lead to unintentional weight loss in patients with chronic illness?
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conditions that interfere with nutrient absorption
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conditions that interfere with ingestion of nutrients
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conditions that alter the daily allowance of nutrients needed
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conditions that decrease metabolic rate
9 .
A nurse is developing a program to promote healthy eating for a local community center. What nutrient should make up the largest daily percentage of intake in a healthy diet?
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carbohydrates
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proteins
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fats
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simple sugars
10 .
A patient is learning to read food labels to help with healthy meal planning. How can the patient identify high nutrient values?
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These nutrients will be listed first.
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The percent daily value per serving will be at least 20 percent.
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The per serving percentage will be at least 50 percent.
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These nutrients will be identified as “added.”
11 .
A patient with a history of chronic constipation is placed on a high-fiber diet. What food or drink should the nurse recommend?
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vegetable juice
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eggs
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peanut butter
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black beans
12 .
Why does PN require administration through a central venous catheter?
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All liquid nutrients are delivered via central line.
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PN must be delivered quickly.
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PN has a high osmolality and causes vein irritation.
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A central line provides direct access to the gastrointestinal tract.
13 .
A patient has been newly diagnosed with anemia. The goal of treatment is to maintain stable hemoglobin levels. What supplement can help increase hemoglobin levels?
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vitamin C
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folate
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magnesium
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calcium
14 .
A nurse is taking a health history. The patient reports that they have a chronic cough, smoke one pack per week, have food allergies, and have a history of dieting. Which has the most impact on nutritional status?
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has a chronic cough
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smokes one pack per week
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has food allergies
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has a history of dieting
15 .
A nurse is discussing the relationship between metabolic syndrome and chronic disease. What activity would help reverse metabolic syndrome?
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increase physical activity
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increase lipid levels
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maintain a high-protein diet
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drink 2 L of water daily


1.14: Getting to the point- importance of immunizations for public health
At the end of this case, students will be able to:
- Define herd immunity and how unvaccinated individuals are protected
- Describe presumptive evidence of immunity
- Explain the timeline of an antibody response
- Describe counseling points to increase adult immunizations
- Discuss when and how to notify public health officials of suspected infectious disease cases
Introduction
Immunizations have led to the eradication of some of the world’s most deadly diseases (such as smallpox) and to significant decreases in incidence of diseases such as rubella and measles. Total eradication is achieved when there is no circulating disease and no further measures to stop the disease are required. Despite significant gains toward the eradication of several infectious diseases, outbreaks may still occur, typically the result of an under-vaccinated population. In these populations, herd immunity (also known as “community immunity”), in which a sufficient proportion of the population is protected from a disease such that transmission among members is unlikely, is insufficient to protect unvaccinated members. 1,2,3 The Office of Disease Prevention and Health Promotion’s (ODPHP) has set several goals of reducing the number of vaccine-preventable diseases in the US. Pharmacists can play a large role in reaching such public health goals by understanding how immunizations confer protection, how diseases circulate in communities and counseling all patients to receive necessary immunizations as appropriate. 4
In 2000, measles was declared eliminated in the US, although it was and still is endemic in other countries. However, since this time, the US has seen resurgence of this vaccine-preventable disease. Resurgence and resulting outbreaks are largely caused by introduction of the virus into a community from unvaccinated, overseas travelers, followed by disease transmission between unvaccinated individuals and those with an unknown vaccine history. 5,6 Acceptable or presumptive evidence of immunity includes written documentation of vaccination, laboratory evidence of immunity, laboratory confirmation of disease or in some cases, the age of an individual. 7 As an example, in April 2017, a measles outbreak was identified in a group of US-born children of Somali descent. 8 An investigation into the outbreak later revealed that this population had been subject to misinformation about vaccines and as a result had developed significant fears about autism. Amidst the outbreak, susceptible, unvaccinated persons believed to have been exposed to the virus were treated with post-exposure prophylaxis with a measles vaccine or immune globulin as per the Advisory Committee on Immunization Practices (ACIP) guidelines. 8 However, the development of an adequate immune response to a vaccine requires several weeks.
From a scientific perspective, effective vaccination involves the development of a strong antibody response. The primary exposure to an antigen of interest (or vaccine) requires B-cells to recognize the antigen, become activated and begin to produce antibodies specific to this antigen as well as memory B-cells. This process can take between one to two weeks. Hence, if an unvaccinated individual is exposed to a pathogen, it is likely that pathology may occur during this development period. Although a certain amount of protection is afforded after initial vaccination, booster vaccinations are often required to further develop memory B-cells. Such memory B-cells can then produce antibodies to the antigen of interest within one to three days with no notable pathology.
The CDC has developed standards for adult immunization practices which may be found on the CDC website. 9 It is well known that many individuals, including adults, are hesitant to receive immunizations. The reasons for adult vaccine hesitancy may be due to a variety of factors, such as complacency (not recognizing the risk of disease), lack of convenience or lack of confidence due to concerns regarding vaccine safety. 10 However, several studies have suggested that a key factor in adult immunization is a strong recommendation from their provider. 11 It is important to understand that a key factor in adults becoming immunized is a strong recommendation from healthcare providers. For example, instead of asking a patient “Are you interested in being vaccinated for pneumococcal disease today?” say “I see it is time you are vaccinated for pneumococcal disease, which can help prevent pneumonia. If you give me a moment, I can prepare the vaccine for you and do it right now.” Pharmacists may also use the acronym SHARE to help them remember key counseling points:
- S : Share why the vaccine is recommended for that particular patient
- H : highlight positive benefits of the vaccine
- A : address patient questions in lay terms
- R : remind that vaccines not only protect the patient, but their loved ones around them
- E : explain the potential costs of disease.

CC: “I’m worried the flu shot will hurt my unborn baby.”
Patient: TF is a 24-year-old female (62”, 58kg), 12 weeks pregnant with her second child.
HPI: TF is at the pharmacy to pick up her prescription for prenatal vitamins. She tells you that her physician recommended that she receive an influenza vaccine. She is hesitant as her first son is on the autism spectrum, and she has heard conflicting stories about vaccines and autism. She would like more information on how vaccines work before agreeing to receive the vaccine.
PMH:
- First pregnancy resulted in live vaginal birth with no complications
- Mild heartburn symptoms during both pregnancies
FH:
- Both parents alive but with unknown health status
- No siblings
- One 4 year old son with ASD, otherwise healthy
SH:
- No alcohol, tobacco, or illicit drug consumption
- Lives with fiancée and son
Medications:
- Prenatal vitamin PO daily
- Calcium carbonate antacid PO as needed for heartburn
Allergies: none
Vitals:
- BP 120/70 mmHg
- HR 65 bpm
Case Questions
- Why is vaccination after exposure to infection not as effective as prior vaccination?
- Why is it important for pharmacists to be aware of diseases circulating within their community of practice?
- How would you respond to a patient that states they do not need to vaccinate because they are healthy and can fight off most vaccine preventable diseases, such as influenza?
- In talking with the patient, she states she stopped vaccinating after her son’s ASD diagnosis. How would you discuss this with her?
- Describe how you could use the acronym SHARE to address this patient’s concerns for her unborn baby and today’s recommendation for an influenza vaccine.
- What other vaccination(s) will the patient need to receive during her pregnancy?
Author Commentary
Immunizations are the best way to protect the general public from the spread of communicable disease. Some diseases such as influenza have several unique strains and hence yearly influenza vaccines are needed. Other vaccines prevent diseases caused by pathogens that do not change significantly over time. Without herd immunity, a population has enough potential disease vectors for a pathogen to circulate easily and infect not only the unvaccinated, but also those too young to receive vaccination or people that may be immune compromised.
Because many people are vaccine hesitant and do not vaccinate themselves or their children there has been a resurgence in some diseases, such as measles. According to the CDC, only 91.1% of children between ages 19-35 months old have received a measles vaccines, short of the 95% desired, and only 47% of children between six months and 17 years receive an influenza vaccine, leaving a significant portion of the population vulnerable to this disease. Vaccine hesitancy continues despite changes in vaccine formulations removing the preservative thimerosal, which was once blamed for adverse effects (although this has been shown to be untrue.) Vaccines are now available in prefilled syringes so preservatives are not included. Vaccines also contain significantly few antigens than in previous years, as vaccinologists have discovered the primary antigens necessary in a vaccine formulation to confer appropriate protection from disease. The use of fewer antigens has been complemented by improved vaccine adjuvants that promote reliable cell mediated and humoral responses to vaccines.
Patient Approaches and Opportunities
Pharmacists are well respected and easily accessible, particularly those involved in community pharmacy. Hence, they often function as a first resource for many people and parents to gain information regarding healthcare. Thus, it is critical that pharmacists are aware of how immunizations can protect a population, especially those that are unable to receive immunizations. Pharmacists should be aware of a patient’s concerns and potential hesitancy regarding vaccination and use the SHARE technique to help talk with patients. Such conversations between the pharmacist and patient may result in patients receiving appropriate referrals and care to further prevent spread of vaccine-preventable diseases.
Related chapters of interest:
- Deciphering immunization codes: making evidence-based recommendations
- Interprofessional collaboration: transforming public health through team work
- An ounce of prevention: pharmacy applications of the USPSTF guidelines
- Immunizing during a pandemic: considerations for COVID-19 vaccinations
- Staying on track: reducing missed immunization opportunities in the pediatric population
External resources:
- Centers for Disease Control and Prevention. Immunization Schedules. https://www.cdc.gov/vaccines/schedules/index.html
- Immunization Action Coalition. http://www.immunize.org
- Centers for Disease Control and Prevention. Manual for the Surveillance of Vaccine-Preventable Diseases. https://www.cdc.gov/vaccines/pubs/surv-manual/index.html
- Centers for Disease Control and Prevention. Community immunity definition. https://www.cdc.gov/vaccines/terms/glossary.html#commimmunity
- Centers for Disease Control and Prevention. Making the Vaccine Decision. https://www.cdc.gov/vaccines/parents/vaccine-decision/index.html
References
- Immunization Action Coalition. http://www.immunize.org/ . Updated August 23, 2018.
- Vaccine Glossary of Terms. Centers for Disease Control and Prevention. https://www.cdc.gov/vaccines/terms/glossary.html#commimmunity . Updated August 17, 2015.
- The History of Vaccines. The College of Physicians of Philadelphia. https://www.historyofvaccines.org/ . Accessed October 2018.
- Healthy People 2020. https://www.healthypeople.gov/2020/topics-objectives/topic/immunization-and-infectious-diseases . Updated February 8, 2019. Accessed February 8, 2019.
- Phadeke VK, Bednarczyk RA, Salmon DA, Omer SB. Association between vaccine refusal and vaccine-preventable diseases in the United States: a review of measles and pertussis. JAMA . 2016;315(11):1149-58.
- Measles Cases and Outbreaks. Centers for Disease Control and Prevention. https://www.cdc.gov/measles/cases-outbreaks.html . Updated February 1, 2019. Accessed February 5, 2019.
- Centers for Disease Control and Prevention. Manual for the surveillance of vaccine-preventable diseases. Centers for Disease Control and Prevention, Atlanta, GA, 2008.
- Hall V, Banerjee E, Kenyon C, et al. Measles outbreak — Minnesota April — May 2017. MMWR Morb Mortal Wkly Rep . 2017;66:713–717.
- Standards for Adult Immunization Practice. Centers for Disease Control and Prevention. https://www.cdc.gov/vaccines/hcp/adults/for-practice/standards/index.html . Updated March 13, 2018. Accessed February 5, 2019.
- Smith T. Vaccine rejection and hesitancy: a review and call to action. Open Forum Infect Dis . 2017;4(3).
- Paterson P, Meurice F, Stanberry LR, Glismann S, Rosenthal SL, Larson HJ. Vaccine hesitancy and healthcare providers. Vaccine . 2016;34(52):6700-6.