1.8: Summary
Infection control and prevention practices are a critical component of patient safety in the health care environment. In order to protect the public and cut health care costs, all health care professionals must take part in preventing infections before they occur. The use of routine practices, effective hand hygiene techniques, additional precautions, and sterile procedures contribute to enhancing patient safety and eliminating significant health care risks such as health care-associated infections. If effectively applied, infection control and prevention practices will prevent and minimize transmission of infections in health care settings.
Key Takeaways
- Hand hygiene is the single most important part of infection prevention and control practices in the health care setting.
- Plan your care: each health care worker is responsible to perform a risk assessment before every contact with a patient and/or patient’s environment to ensure the proper control measures are in place to prevent transmission of infections.
- The most common sites for HAIs are the urinary tract and the respiratory tract. It is vital to implement preventive measures at all times during patient care or during procedures related to these areas.
- Be aware of potential risk factors of patients that make them more susceptible to infections. Susceptible patients include very young children; patients who are elderly, nutritionally deficient, or chronically ill; patients undergoing medical treatments such as chemotherapy or taking medications such as high doses of steroids; and individuals who are already ill or have open wounds (Perry et al., 2014).
- Be aware how the chain of infection works and implement ways to break the chain of infection in practice.
- Practise strict adherence to the principles of sterile technique to prevent and minimize infections during sterile and invasive procedures.
Suggested Online Resources
1. BC Centre for Disease Control: Blood and body fluid exposure management. This resource outlines risk assessment and guidelines for potential exposures of percutaneous, permucosal, and non-intact skin to HIV, hepatitis B, and hepatitis C.
2. British Columbia: Home and community care – Policy manual. This manual offers guidelines for working in the community and residential care.
3. Centers for Disease Control and Prevention: Antibiotic/antimicrobial resistance . This resource covers common viruses/bacteria found in the health care setting, such as:
- Clostridium difficile infection (CDI)
- Carbapenemase-producing organisms (CPO)
- Multi-drug-resistant organisms (MDRO) or antibiotic-resistant organisms (ARO): MRSA/VRE
- Severe acute respiratory syndrome (SARS)
- Middle East respiratory syndrome (MERS)
- Ebola virus disease (EVD)
4. Centers for Disease Control and Prevention: Guidelines for disinfection and sterilization in healthcare facilities . The goal of this document is to reduce the rates of health care associated infections. Each recommendation listed is categorized according to scientific evidence, theoretical rationale, and applicability.
5. Infection and Prevention Control Canada. (IPAC): Evidence-based guidelines. This website offers the latest reports, guidelines, standards, and policies related to infection control issues. U.S. and international resources are also provided. These documents may be used to support your own documentation practice and best practices.
6. Ontario Agency for Health Protection and Promotion: Routine practices and additional precautions. This excellent resource provides routine practice and additional precautions in all health care settings. These were developed by the Ontario Provincial Infectious Disease Advisory Committee (PIDAC) on Infection Prevention and Control (IPC).
7. Provincial Infection Control Network of British Columbia (PICNet): BC infection control and hand hygiene module. This course teaches the basic principles of infection control in the health care system, sharps management, hand hygiene, blood and body fluid exposure and cleanup, the proper use of personal protective equipment, and isolation precautions.
8. Provincial Infection Control Network of British Columbia (PICNet): Infection control guidelines.Providing health care to the client living in the community.
PICNet Educational Links.This document is intended to provide guidance in the writing of policies pertaining to infection prevention and control within community health care, and home care programs and settings.
9. Public Health Agency of Canada: Hand hygiene practices in healthcare settings . This excellent Canadian resource covers infectious disease prevention and control policies.
10. World Health Organization: Clean care is safer care. This website provides links to the five moments in hand hygiene, diagrams on hand washing and hand rubs, and leaflets for teaching.
References
Accreditation Canada. (2013). Infection prevention and control. Mentum Quarterly , 5(4). Retrieved on Feb 28, 2015, from: www.accreditation.ca/sites/de...pring-2013.pdf
American Academy of Allergy, Asthma and Immunology. (2015). Latex allergies: Tips to remember. Retrieved on Feb 28, 2015, from: www.aaaai.org/conditions-and-...x-Allergy.aspx
ATI. (2015a). Traditional hand scrub method. Retrieved from ATI Nursing Education. Surgical Asepsis. Retrieved on Oct 10, 2015, from atitesting.com/ati_next_gen/s...tradscrub.html
ATI. (2015b). Open-gloving technique. Retrieved from ATI Nursing Education. Surgical Asepsis. Retrieved on Oct 10, 2015, from atitesting.com/ati_next_gen/s...love-open.html
ATI. (2015c). Setting up a sterile field. Retrieved from ATI Nursing Education. Surgical Asepsis. Retrieved on Oct 10, 2015, from atitesting.com/ati_next_gen/s...ent/field.html
Barratt, R. L., Shaban, R., & Moyle, W. (2011). Patient experience from source isolation: Lessons from clinical practice. Contemporary Nurse , 39(2), 180-193. doi: 10.5172/conu.2011.180
Bartlett, G. E., Pollard, T. C., Bowker, K. E., & Bannister, G. C. (2002). Effect of jewellery on surface bacterial counts of operating theatres. The Journal of Hospital Infection , 52(1), 68-70.
BC Centre for Disease Control (BCCDC). (2014). Hand hygiene. Retrieved on Feb 21, 2015, from: www.bccdc.ca/prevention/HandH...ne/default.htm
BC Centre for Disease Control (BCCDC). (2015). Communicable Disease Control. Blood and body fluid exposure management. Retrieved on Nov 6, 2015 from
www.bccdc.ca/NR/rdonlyres/E6A...t_20150715.pdf
Berman, A., & Snyder S. J. (2016). Skills in clinical nursing (8th ed.). Upper Saddle River, New Jersey: Pearson.
Bissett, L. (2007). Skin care: An essential component of hand hygiene and infection control. British Journal of Nursing , 16(16), 976-981.
Braswell, M. L., & Spruce, L. (2012). Implementing AORN recommended practices for surgical attire. AORN Journal , 95(1), 122-140. doi: 10.1016/j.aorn.2011.10.017
Centers for Disease Control and Prevention (CDC). (2007). Part III: Precautions to prevent the transmission of infectious agents. Retrieved on Oct 10, 2015, from http://www.cdc.gov/hicpac/2007IP/2007ip_part3.html
Centers for Disease Control (CDC). (2012). Frequently asked questions about Clostridium difficile for healthcare providers. Retrieved on Feb 27, 2015, from http://www.cdc.gov/HAI/organisms/cdiff/Cdiff_faqs_HCP.html
Centers for Disease Control (CDC). (2014). Types of healthcare-associated infections. Retrieved on Feb 27, 2015, from http://www.cdc.gov/HAI/infectionTypes.html
Infection Control Today. (2000). Asepsis and aseptic practices in the operating room. Retrieved on Oct 10, 2015, from www.infectioncontroltoday.com/articles/2000/07/asepsis-and-aseptic-practices-in-the-operating-ro.aspx
Kampf, G., & Loffler, H. (2003). Dermatological aspects of a successful introduction and continuation of alcohol based hand rubs for hygienic hand disinfection. The Journal of Hospital Infection , 55(1), 1-7.
Kennedy, L. (2013). Implementing AORN recommended practices for sterile technique. AORN Journal , 98(1), 14-26.
Longtin, Y., Sax, H., Allegranzi, B., Schneider, F., & Pittet, D. (2011). Hand hygiene. New England Journal of Medicine , 34(13) 24-28. Retreived on Feb 27, 2015, from http://www.nejm.org/doi/pdf/10.1056/NEJMvcm0903599
Operating Room Nurses Association of Canada (ORNAC). (2011). Standards, guidelines and position statements for perioperative registered nursing practice. Retrieved on Oct 10, 2015, from flex5114.weebly.com/uploads/1..._standards.pdf
Patrick, M., & Van Wicklin, S. A. (2012). AORN recommended practice for hand hygiene. AORN Journal , 9(4), 492-507. doi; 10.1016/j.aorn.2012.01.019 492
Perry, A. G., Potter, P. A., & Ostendorf, W. R. (2014). Clinical skills and nursing techniques (8th ed.). St Louis, MO: Elsevier-Mosby.
Provincial Infectious Diseases Advisory Committee (PIDAC) (Ontario Agency for Health Provincial Infectious Disease Advisory Committee). (2012). Routine practices and additional precautions in all health care settings (3rd ed.). Toronto, ON: Queen’s Printer for Ontario. Retrieved on Feb 20, 2015, from http://www.publichealthontario.ca/en/eRepository/RPAP_All_HealthCare_Settings_Eng2012.pdf
Poutanen, S. M., Vearncombe, M., McGeer, A. J., Gardam, M., Large, G., & Simor, A. E. (2005). Nonsocomial acquisition of methicillin-resistant Staphylococcus aureus during an outbreak of severe acute respiratory syndrome. Infection Control Hospital Epidemiology , 26(2) 134-137.
Public Health Agency of Canada (PHAC). (2012a). Hand hygiene practices in healthcare settings. Retrieved on Feb 26, 2015, from http://publications.gc.ca/site/eng/430135/publication.html
Public Health Agency of Canada (PHAC). (2012b). Routine practices and additional precautions for preventing the transmission of infection in healthcare settings. Retrieved on Feb 26, 2015, from www.phac-aspc.gc.ca/nois-sinp/guide/ summary-sommaire/tihs-tims-eng.php
Public Health Agency of Canada (PHAC). (2013). The Chief Public Health Officer’s report on the state of public health in Canada: Infectious disease, the never ending threat. Retrieved on Feb 26, 2105, from http://www.phac-aspc.gc.ca/cphorsphc-respcacsp/2013/infections-eng.php#a8
Rothrock, J. C. (2014). Care of the patient in surgery . St. Louis, MO: Mosby Elsevier.
Siegel, J. D., Rhinehart, E., Jackson, M., & the Healthcare Infection Control Practices Advisory Committee (HICPAC). (2007). Guidelines for isolation precautions: Preventing transmission of infectious agents in healthcare settings. Centers for Disease Control. Retrieved on Feb 17, 2015, from: http://www.cdc.gov/hicpac/pdf/isolation/Isolation2007.pdf
World Health Organization (WHO). (2009a). WHO guidelines for hand hygiene in health care: First global patient safety challenge. Retrieved on Feb 6, 2015, from http://whqlibdoc.who.int/publication...6_eng.pdf?ua=1
World Health Organization (WHO). (2009b). Five moments for hand hygiene. Retrieved on March 1, 2015, from: http://www.who.int/gpsc/tools/Five_moments/en/


11.12: Assignment- Test of Independence Using Technology
The purpose of this activity is to gain experience conducting a chi-square test of independence using technology.
Recall the report On the Front Line: The Work of First Responders in a Post-9/11 World . We will use data from this report to investigate the question: Are alcohol-related problems among New York firefighters associated with participation in the 9/11 rescue?
Here again are our observed data:
Question 1:
State the appropriate hypotheses for the chi-square test for independence in this case.
Now you will check whether the conditions for the chi-square test are met. In order to do this, you’ll need to first launch the actual research report and read the last paragraph on page iii of the introduction (starting with the “The study was fully funded…”)
Instructions
Click on the link corresponding to your statistical package to see instructions for completing the activity, and then answer the questions below.
R | StatCrunch | Minitab | Excel | TI Calculator
Question 2:
Does the data meet the conditions for the chi-square test?
Instructions
Click on the link corresponding to your statistical package to see instructions for completing the activity, and then answer the questions below.
R | StatCrunch | Minitab | Excel | TI Calculator
Question 3:
State your conclusion in context. Also explain what the P-value means as a conditional probability based on the null hypothesis.
Contributors and Attributions
- Concepts in Statistics. Provided by : Open Learning Initiative. Located at : http://oli.cmu.edu . License : CC BY: Attribution


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11.6: Chapter Review - Key Terms
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Key Terms
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bar chart
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horizontal column chart
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benchmarking
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tool that checks the validity of your data with similar datasets or a set standard
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Calculated Field
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tool that allows addition of columns of calculations to a PivotTable
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categorical data
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data that is grouped into categories based on attributes or characteristics
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clustered column chart
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column chart that includes multiple variables to show the comparison between the groups
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combination chart
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chart that combines two different chart types in one visual
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continuous data
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information that is measured and can take on an infinite set of values
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Correlation
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used to analyze the relationship between two variables
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data validation
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process of ensuring that data values fall within a predetermined range
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data verification
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process used to ensure that your data is accurate and reliable
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discrete data
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information that can only take on a specific set of values
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histogram
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chart that displays the number of occurrences of data within a defined range
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line chart
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chart used to show changes over time
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numerical data
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data that is quantitative and represents measures of the variables
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qualitative data
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categorical information that does not include numbers; if it does include numbers, they do not have a true mathematical meaning
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quantitative data
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data that involves numerical evaluations
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scatter chart
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chart used to show the relationship between two variables
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slicer
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visual, interactive way to filter data in a PivotTable
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sparkline
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small charts inserted into cells next to data that show changes over time


9.3: Adding New Assignments
Add New Assignment
Assignments in Adapt normally consist of one or more assessments (questions). You can learn how to add assessments here (coming soon). To create a new assignment:
- Log in to your instructors account and select the course that you want to add a new assignment to.
- Click “New Assignment”
- In the opened overlay window fill out assignment properties. Click “Submit” to save the assignment.
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Name - The name of the assignment that will be displayed for instructors and students
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Assignment group - You can choose an existing group or create a new group for this assignment.
Note: you can assign Group score weights in Course Properties → Assignment Group Weights
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Source
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Select “Internal” if you are using LibreTexts database or Query Library.
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Select “External” if you are planning on adding/importing scores from another source manually.
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Scoring Type
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Performance - students get credit for correct answers. Partial credit is possible with delayed grading.
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Completion - with Real Time Grading, students get full credit for completing the assessment regardless of whether the answer they provided is correct. Open-ended questions are graded manually. If the assignment has both types of questions (open-ended and auto-graded) students will get full credit for auto-graded assessments and the open-ended questions will require manual grading.
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Default Points/Question will be applied to all questions by default, but can be changed for each question manually later on.
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Assessment type
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Real Time - works best for auto-graded questions, students are provided with the feedback immediately after submitting their answer. Scores are also released at the time of submission.
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Delayed Graded Assessments: this type will require manual grading. Students won’t get their scores and feedback until the scores are released.
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Learning Tree Assessments: this type is only appropriate for learning trees.
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Clicker Assessments: this type is only appropriate for clicker questions.
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Default Open-ended Submission Type:
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Rich Text has additional formatting options compare to plain text
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Plain Text has no additional formatting options available
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File - lets students upload submissions as PDF, TXT, PNG, JPEG, JPG
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Audio - this type of submission allows students to record audio as their answer and submit it. Note: Audio feedback from graders is also available (see tutorial for grading).
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None - students won’t have any additional field for submission. Works well for auto-graded questions (H5P, WeBWorK, etc.)
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Late Policy
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Do not accept late - once the deadline has passed students cannot submit their answers.
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Accept but mark late - in this case the assignment will be marked late, but no points will automatically be deducted. You will need to set the final submission deadline before saving the settings.
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Accept late with a deduction - The most flexible way to apply credit deduction. You can set deduction percent and choose whether you want it deducted once or periodically (i.e. every 10 minutes, 2 hours, 1 day).
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Include in Final Score
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Include the assignment in computing a final weighted score - the score will be included in the final score calculation
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Do not include the assignment in computing a final weighted score - the score will not be included in the final score
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Instructions (Optional) - these instructions will be shown to students before they see the first question of the assignment.
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Randomization
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No - show all questions added to the assignment to students
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Yes - only show a specific number of questions out of all questions you’ve added to this assignment. You will need to indicate the number of randomized assessments. The bigger the pool of questions, the greater the chance that all students will get a different set of randomized questions.
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Notifications - if students opted-in to receive notifications they will be notified if you select “Yes”
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Assign to - select one or several students, specific section or all students enrolled in this course
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Available on - date when the assignment will be first available to students
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Due Date - Deadline for the assignment
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Final submission Deadline - If you select “Accept but mark late” or “Accept late with a deduction” you will be asked to provide this deadline after which the submissions will not be accepted anymore.
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Add Assign to - use this option to assign special deadlines for a specific student/section
Import assignments
- Log in to your instructors account and select the course that you want to add a new assignment to.
- Click "Import Assignment".
- You can choose to import Just the properties from another of your assignment (see the list above) and add different questions to it or import Properties and questions from one of your assignments.
- Click "Yes, Import Assignment" to complete the import.


7.6: Transactional and Transformational Leadership
Huberts, Kaptein, and Lasthuizen (2007) found that effective role modelling is especially significant in demonstrating moral behaviour, while strictness is especially effective in limiting fraud, corruption, and the misuse of resources. As an extension of strictness, the ethics of law enforcement agencies are likely to be greater when there are rules, regulations, and systems of oversight that carefully manage law enforcement behaviour. In the case of law enforcement agencies, the behaviour usually occurs on the street, where street police officers are interacting with civilians without supervision. Because the police are out of view and not supervised for much of their working day, leadership must evolve away from strictness as a way to promote ethical conduct.
There are two distinct models of leadership that operate within large organizations: transformational and transactional. Historically, due to the paramilitary nature of law enforcement, leadership has largely been transactional. Transactional leadership in law enforcement is a style of management used by those who are more oriented toward bureaucracy and maintaining the status quo. Transactional leaders tend to take the decision-making powers away from those they supervise and to make decisions on their own, not yielding power to those beneath them in the hierarchy. This leadership style often runs contrary to what is practised in law enforcement: the requirement to exercise discretion throughout the ranks (Bass, 1990).
Bowie (2000) asserts that leadership is not effective unless managers empower subordinates to make decisions; however, the empowerment of subordinates is at odds with the military hierarchical system. What is required is a system that allows subordinates to make operational decisions and leadership that is willing to risk the mistakes that result from these decisions. Mastrofski (2004) suggests the way to achieve these goals is through transformational leadership , which guides officers to make the right decisions by following the moral lead of their managers who possess the moral standards that are shared by the organization. Failure to promote these values will lead subordinates to mirror the unethical practices of their leader, resulting in poor decisions. There are risks associated in allowing subordinates to use discretion, such as forgetting, missing, or just not adhering to the morals of their leader; risk is unavoidable when subordinates are given increased discretion.
The risk of poor decisions at the operational level requires strong leadership in which managers not only understand the risk but also are willing and able to bear the weight of this risk (Villiers, 2003). Such a style of leadership is difficult within a culture that is so deeply entrenched in a military type of structure, where following policy and rules are expected throughout the hierarchy. Villiers (2003, p. 28) describes this as “mechanistic bureaucratization” in which the policing service operates in an autocratic style, which is contrary to the autonomy police officers have in exercising their discretion. Villiers (2003) further argues that a more democratic style of leadership is required in order to effectively lead the officer who exercises more discretion than his or her manager.
Transformational leadership is conducive to discretionary policing and, in its purest form, empowers subordinates to make moral decisions that are reflective of the organization (Bass, 1990). The transformational leader requires followers to transcend their own interests to uphold the interests of the organization by focusing on future and long-term goals instead of short-term satisfaction (Bass, 1990). A transformational leader is required to exert his or her organizational morals on subordinates who will in turn make decisions that reflect the leader’s values and therefore the organization’s values. The result of such effective leadership is a subordinate who, when confronted with operational decisions, will be able to make the same decisions that his or her leader would make. In this way, a transformational leader is a “developer of people and a builder of teams who inspire their followers to act and make decisions” (Bass, 1990, p.54). Bass (1990) further describes those that possess such qualities as being naturally gifted and suggests that one is either born with the trait or not, which renders them a valuable commodity.
The notion that transformational leaders are born, not made, presents a problem for law enforcement agencies that need sergeants and other managers to possess both operational knowledge and transformational qualities. The possibility that managers cannot be taught transformational qualities potentially eliminates those who hold only operational knowledge as an attribute. Tourish, Craig, and Amernic (2010, p.41) describe such leaders as “exceptional people” who are also powerful and have the ability to understand organizational values as well as the personalities of their followers. Police managers, having risen through the ranks, may or may not be capable of developing such attributes and as result, require training. In their qualitative study of managers, Hay and Hodgkinson (2006) found managers who felt that training in these qualities is a difficult prospect and something that cannot be learned in courses. This makes it difficult for those police managers who are not born with these qualities to learn and apply them on a regular basis. Courses in leadership are used to train officers of all ranks; however, there have been few studies that have determined whether this training leads to transformational leadership or not. The question remains: can competent operational officers learn the skills to be transformational leaders?
The notion of transformational leadership in policing is sometimes at odds with police culture for the following reasons:
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Officers are unlikely to embrace the transformational leader due to their inculcation in the blame culture where blame is assessed when discretion has failed and a mistake is made (Villiers, 2003). The blame culture is a double-edged sword:
- First, operational officers mistrust their superiors, believing that if they make a mistake, they will be held accountable.
- Second, managers have difficultly extricating themselves from the blame culture when assessing the poor discretionary decision of a subordinate.
- Police culture is generally characterized by cynicism toward leadership, and this is especially true toward leaders who are charismatic and are purveyors of transformational leadership values (Villiers, 2003).
- Transformational leaders must fight the blame culture and be willing to accept the inevitable risk associated with decisions made at the operational level. As discretion increases, so too does the risk of more mistakes. The manager who assumes the role of transformational leader must accept this risk as a part of officers’ development rather than as an opportunity to blame.
- In acknowledging the inevitability of discretion, Mastrofski (2004) maps out transformational leadership as the best way to ensure proper and effective control of discretion among operational police officers. Transformational leadership convinces officers to make the right discretionary choices by persuading them to achieve the right goals without the need to directly supervise them. Officers functioning beyond the view of their superiors will need to use discretion, and if they have adopted the values of their leader (and therefore their organization), they will likely make decisions that are based on these shared values (Bass, 1990).


7.8: Ending Your Practicum
It is to be expected that the end of your practicum may bring a variety of feelings swirling toward you. You may be relieved that it is over, or you may be excited to be graduating and DONE! 😊 There are some practical items to consider at this time. These include saying goodbye to clients, your site supervisor, and your colleagues at the agency. Additionally, you will have a final evaluation by your supervisor at the agency and your experience will be graded. Some students will have a job offer on the table, and may not be leaving, but instead, entering into a new role as a paid employee.
Taking time to write a thank you note to your supervisor is always a good idea. It is certainly a small world and you are likely to run into that person again. Plus, it is simply good to thank a person who helped you in your formation as a human service professional. All of these considerations are also happening at a time when you are stressed at the end of the semester. Take a moment to reflect on your learning. Take stock of what areas you did well in, and those for which you may need to refine your skills. Finally, give yourself credit for all the hard work you did over the practicum experience. You did it!


1: The Digital World- Building on What You Already Know to Respond Critically
Your past experiences with computers, cell phones, and other electronic devices represent your conscious choice to connect with a global community. For example, you may post on social media sites where you receive instant feedback from around the world in the form of reposts or likes. Through these interactions, you are empowered to influence people more than at any other point in history. In fact, you may be on the road to becoming the next big social media influencer—a person with established credentials in a certain field with access to a large audience and who, because of popularity, can influence others’ actions. With applications that instantly translate into many languages, even language has become less of a barrier to your potential audience and thus to your potential influence. However, even though the world may be more connected now than ever before and communication may be faster, easier, more powerful, and more widely accessible, the basics of communication have not changed.
Figure \(1.1\) Whether these students realize it or not, they are engaging in rhetoric by consuming and posting information on social media. (credit: "Together and Alone" by Garry Knight/flickr, CC-BY)
The essential element of all communication, past and present, including your social media posts and related comments, is the rhetorical situation : the conditions , or circumstances, of the communication and the agents , or people involved, in that communication. Notice that the term comes from the word rhetoric . Originally, rhetoric referred to the art of persuasive speaking or writing. Now it is used more inclusively to mean the “techniques and theories of communication.” And notice, too, that like the people in Figure \(1.1\), you are already using rhetoric every day as you find yourself in different rhetorical situations on social media. In this chapter, you will learn more about the use of rhetoric within rhetorical situations as you begin the journey of constructing bridges among the communication taking place on social media, in the world of academia, and in the world at large.


27.4B: The Cambrian Explosion of Animal Life
- Compare the theories that attempt to explain the Cambrian Explosion
The Cambrian Explosion of Animal Life
The Cambrian period, occurring between approximately 542–488 million years ago, marks the most rapid evolution of new animal phyla and animal diversity in earth’s history. It is believed that most of the animal phyla in existence today had their origins during this time, often referred to as the Cambrian explosion. Echinoderms, mollusks, worms, arthropods, and chordates arose during this period. One of the most dominant species during the Cambrian period was the trilobite, an arthropod that was among the first animals to exhibit a sense of vision.
The causes of the Cambrian explosion are still debated. There are many theories that attempt to answer this question. Environmental changes may have created a more suitable environment for animal life. Examples of these changes include rising atmospheric oxygen levels and large increases in oceanic calcium concentrations that preceded the Cambrian period. Some scientists believe that an expansive, continental shelf with numerous shallow lagoons or pools provided the necessary living space for larger numbers of different types of animals to co-exist. There is also support for theories that argue that ecological relationships between species, such as changes in the food web, competition for food and space, and predator-prey relationships, were primed to promote a sudden, massive coevolution of species. Yet other theories claim genetic and developmental reasons for the Cambrian explosion. The morphological flexibility and complexity of animal development afforded by the evolution of Hox control genes may have provided the necessary opportunities for increases in possible animal morphologies at the time of the Cambrian period. Theories that attempt to explain why the Cambrian explosion happened must be able to provide valid reasons for the massive animal diversification, as well as explain why it happened when it did. There is evidence that both supports and refutes each of the theories described above. The answer may very well be a combination of these and other theories.
Unresolved questions about the animal diversification that took place during the Cambrian period remain. For example, we do not understand how the evolution of so many species occurred in such a short period of time. Was there really an “explosion” of life at this particular time? Some scientists question the validity of this idea because there is increasing evidence to suggest that more animal life existed prior to the Cambrian period and that other similar species’ so-called explosions (or radiations) occurred later in history as well. Furthermore, the vast diversification of animal species that appears to have begun during the Cambrian period continued well into the following Ordovician period. Despite some of these arguments, most scientists agree that the Cambrian period marked a time of impressively-rapid animal evolution and diversification that is unmatched elsewhere during history.
Key Points
- Echinoderms, mollusks, worms, chordates, and arthropods (including arthropods called trilobites which were the one of the first species to exhibit a sense of vision) developed during the Cambrian period.
- Environmental changes such as rising levels of atmospheric oxygen and an increase in oceanic calcium concentrations may have caused The Cambrian Explosion.
- A continental shelf with numerous shallow pools that provided the necessary living space for larger numbers of different types of animals to co-exist may have caused the Cambrian Explosion.
- The Cambrian Explosion may have been a result of ecological relationships between species, such as changes in the food web, competition for food and space, and predator-prey relationships.
- The evolution of Hox control genes resulting in animal complexity and flexibility may have provided the necessary opportunities for increases in possible animal morphologies.
Key Terms
- Ordovician period : covers the time between 485-443 million years ago; followed the Cambrian period
- Cambrian explosion : the relatively rapid appearance (over a period of many millions of years), around 530 million years ago, of most major animal phyla as demonstrated in the fossil record


1.4: Nutrient Cycling
Nutrient cycling is yet another critical service provided by biodiversity -- particularly by microorganisms. Fungi and other microorganisms in soil help break down dead plants and animals, eventually converting this organic matter into nutrients that enrich the soil (Pimentel et al. 1995).
Nitrogen is essential for plant growth, and an insufficient quantity of it limits plant production in both natural and agricultural ecosystems. While nitrogen is abundant in the atmosphere, only a few organisms (commonly known as nitrogen-fixing bacteria) can use it in this form. Nitrogen-fixing bacteria extract nitrogen from the air, and transform it into ammonia, then other bacteria further break down this ammonia into nitrogenous compounds that can be absorbed and used by most plants. In addition to their role in decomposition and hence nutrient cycling, microorganisms also help detoxify waste, changing waste products into forms less harmful to humans.


1.17: Cosmological Data Analysis
We focus in this chapter on the analysis of cosmological data. Most of what I present in this chapter applies much more broadly; in fact, nothing in this text book is of broader utility. However, the presentation here is entirely focused on application to cosmology. We wish to learn from measurements of the cosmos. These measurements are never 100% precise, and thus we need a means of dealing with uncertainty. We necessarily deal in probabilities.
This is especially true for the practitioner interested in discovering something new. Almost always, the data are not overwhelmingly and obviously convincing of the new truth that they potentially reveal. Data analysis in cosmology is an exciting process of sorting out whether one is on the cusp of an exciting discovery, or on the cusp of embarrassing oneself by claiming something that turns out not to be true. It calls for rigor of process and high integrity. Engaging in it, in the right way, will raise one's standards of what it means to know something. One needs to search not only for the evidence that supports one's hunch of what's going on, but also, very importantly, one needs to search for evidence that supports alternative explanations. We are after the truth.
There are two distinct aspects of data analysis: model comparison and parameter estimation. In model comparison we try to determine which model is better than another. In parameter estimation, we have one assumed model and we are estimating the parameters of that model. We focus here on parameter estimation.
Modeling data: a simple example
Let's start by considering a simple measurement of length, to have a specific example in mind. The signal would be the true length, \(\ell\), and our model of the data might be
\[d = \ell + n\]
where \(d\) is the measurement (our data) and \(n\) is the error in the measurement, the difference between the data and the true length, \(\ell\). We are fundamentally interested in the probability distribution of the length, given this data. The length is the one parameter of our model. (More generally, we are interested in the joint probability distribution, given the data, of all the parameters of our model.)
A measurement, if it is to mean anything at all, has to come along with an estimate of the uncertainty in the measurement. How to estimate the uncertainty is a subject we won't explore here. We are going to assume the measurement has been done and the uncertainty in it has been accurately determined. We will further assume here for simplicity that the uncertainty can be described with a normal distribution. In our one-dimensional example this means that
\[P(n) = \frac{1}{\sqrt{2\pi} \sigma} \exp(-\frac{n^2}{2\sigma^2}) \]
is the probability density for the error, \(n\). What is a probability density you ask? This one tells us the amount of probability that there is between \(n\) and \(n + dn\): it's equal to \(P(n) dn\). The pre-factor out in front of the exponential is there to keep \(P(n)\) properly normalized so that
\[ \int_{-\infty}^\infty dn P(n) = 1. \]
It should integrate to 1 because \(n\) takes on one and only one value (even if we don't know what that value is).
A fundamentally important quantity is the probability of some data, \(d\), given the signal \(s\) (or, in our example, \(\ell\) ). Since \(n = d-\ell\) we can write
\[P(d | \ell) = P(n) = \frac{1}{\sqrt{2\pi} \sigma} \exp\left(-\frac{(d-\ell)^2}{2\sigma^2}\right) \]
as the probability density of \(d\) given that the length is \( \ell \). That is, if we knew the true length was \(\ell\) then how probable is it to have \(d\) in the range \([d, d+dd]\)? Answer: \( P(d|\ell) dd\). (What we mean here by \(dd\) is an infinitesimal increment to \(d\)).
Bayes' Theorem
Although we have an expression that tells us the probability of the data given the true value of the underlying parameter, we are actually in a position of wanting the exact opposite! We know what the data is and we desire to know what the true length is -- or, more preciesly, since we can't have perfect knowledge of the length, our goal is to know the probability that the length takes on any particular value: we want \(P(\ell | d)\). Bayes' theorem helps us get from one to the other. It follows from fundamental axioms of probability theory. For simplicity, for the purposes of deriving Bayes' theorem, we are going to start considering discrete outcomes, like we get with the flip of a coin, or the roll of dice. Let's introduce the joint probability \(P(A,B\) where \(A\) might be a particular outcome for a six-sided die and \(B\) might be the sum of that outcome with that of another die. I've purposely constructed this example so that \(A\) and \(B\) are not independent. By the joint distribution, we mean that \(P(A,B)\) tells us the probability that the first quantity is \(A\) and the second quantity is \(B\).
I'll give you the calculation of \(P(A=3 , B= 8)\). There's only one way for this to happen.  With a roll of two die this is one of 36 possible and equivalent outcomes, so the probability is 1/36. Of course, the probability that \(B < A\) is zero.
Exercise: Calculate these probabilities given the above definition of \(A\) and \(B\): \(P(A=5 , B= 6)\), \(P(A=5 , B= 3)\),\(P(A=3 , B=7 )\).
It is a fundamental rule of probability that \(P(A,B) = P(A|B)P(B)\). The joint distribution is symmetric so it is also true that \(P(A,B) = P(B|A)P(A)\).
Exercise: From the preceding two equations derive \(P(A|B) = P(B|A)P(A)/P(B)\).
In our special case of interest, if we call our model parameters \( \theta\) this becomes Bayes' theorem:
\[P(\theta | d) = \frac{P(d | \theta) P(\theta)}{P(d)}.\]
Bayes' theorem describes learning from data. When we learn something, we're usually not starting from complete ignorance. The factor \(P(\theta)\) is called the prior probability distribution, or simply, 'the prior.' It represents what we know about the model parameters prior to examining the data. The probability density \(P(d|\theta)\) (at least when thought of as a function of \theta) is called the likelhood. The denominator, \(P(d)\), I find difficult to understand conceptually. It's the probability of the data, but we know the data. That's confusing. But there is an easier way to think about it for purposes of parameter estimation: it is just a normalizing constant. The reason we can do this is that, by assumption, the model is correct and so \(\theta\) must take on one value; i.e., if we integrate the posterior over all possible values of \(\theta\) then it must be equal to 1. Forcing this to be true will determine the value of \(P(d)\) if one knows the likelihood and the prior. One can do the integral without knowing \(P(d)\) because \(P(d)\) does not depend on \(\theta\).
The term on the left-hand side of the above equation is called the 'posterior probability distribution', or sometimes simply 'the posterior.' Getting back to thinking of Bayes' theorem as a description of learning from data, we can now see that the likelihood serves to update our prior beliefs, incorporating what we've learned from data, and what we know already, into the posterior probability distribution for \(\theta\); i.e., what we know about \(\theta\) after we have studied the data. Usually we don't care about the normalization -- we just want to know how probable one value of \(\theta\) is compared to another.
Modeling measurements of supernova apparent magnitude
Let's now turn to the case of modeling our supernova data. Let's take the model parameters to be \(\theta = \{M, \Omega_\Lambda, \Omega_m, H_0\}\). The data we take to be the supernova apparent magnitudes. The likelihood we take to be normally distributed (as we are assuming the errors in the magnitudes are normally distributed). Therefore we have
\[ L(\theta) = P(d|\theta) \propto \exp(-\chi^2/2) \ \ ; \ \ \chi^2 = \Sigma_i (m_i^d -m_i^m)^2/\sigma_i^2 \]
where
\[m_i^m = M + 5 \log_{10}\left(\frac{D_L(H_0,\Omega_\Lambda,\Omega_m; z_i)}{\rm Mpc}\right) + 25.\]
We take a prior that is uniform in \( \Omega_\Lambda, \Omega_m\) and \(H_0\) and normally distributed in \(M\) so that
\[ P(\theta) \propto \exp(-\chi^2_M/2)\ \ ; \ \ \chi^2_M = (M-(-19.26))^2/\sigma_M^2 \]
with \(\sigma_M = 0.05\). This mean and \(\sigma\) for \(M\) is consistent with the Riess et al. (2018) determination of the Hubble constant with a standard error of 2.2%, assuming that uncertainty is entirely due to uncertainty in supernova absolute magnitude calibration. We can now take the above prior and the above likelihood and multiply them together to form the posterior (up to an unknown normalization constant that we don't care about).
Marginalization
It is often the case that we do not care about all the parameters of our model. Maybe we only care about \(\Omega_m\) and \(\Omega_\Lambda\). In that case we might want to calculate \( P(\Omega_m,\Omega_\Lambda|d)\). This probability density should include the probability associated with all values of the other parameters. It is related to the full joint distribution by integration over the other parameters via:
\[P(\Omega_m,\Omega_\Lambda|d) = \int dH_0 dM P(H_0,\Omega_\Lambda,\Omega_\Lambda, M|d). \]
This process of integrating over parameters is called marginalization.
Contour plots
A common way of presenting a two-dimensional probability distribution is a contour plot. The axes of the contour plot are the two parameters, and the contours indicate curves of constant probability density. Often there will be two different curves plotted: one that encloses 68% of the probability and another that encloses 95% of the probability. The enclosed regions are the 68\% confidence region and the 95% confidence region, respectively.
An example contour plot is shown in the figure at the beginning of this chapter. The contours labeled "R98" discovery sample give the 68% and 95% confidence regions given the Riess et al. (1998) data that were used for the discovery of cosmic acceleration. The red and dark red shaded regions are the 68% and 95% confidence regions, respectively, given the Scolnic et al. (2018) supernova data, but only taking into account some of the sources of error. The authors distinguish some of their errors as systematic, as opposed to statistical. Including the systematic errors as well leads to the grey contours. The shrinkage from the R98 contours to the gray contours indicates the progress that has occurred in supernova cosmology over the 20 years from 1998 to 2018.
If the probability density is Gaussian then the contours are such that \( 2\ln(P_{peak}/P_{68}) = 2.3 \) and \( 2\ln(P_{peak}/P_{95}) = 6.17 \), where \(P_{peak}\) is the probability density evaluated at its maximum and \( P_{68} \) ( \(P_{95}\) ) is the probability density whose contour contains 68.3% (95.4%) of the data. (You might wonder where these extra significant figures come from to make this 68.3 and 95.4. They come from one-dimensional normal probability distributions. For a normal one-dimensional distribution, 68.3% of the probability is to be found in between one standard deviation (\( \sigma ) \) less than the mean, and one standard deviation more than the mean while 95.4\% of the probability is to be found in between two standard deviations less than the mean, and two standard deviations more than the mean.)
Homework:
18.1: Estimate \(H_0\). To reduce dimensionality, in order to make things simpler, set \( \Omega_\Lambda = 1-\Omega_m = 0.7\). Take \(M\) to be governed by the above prior. Use the Scolnic et al. (2018) data (available in 'supernova_data.txt') to make a contour plot in the \(H_0, M\) plane.
18.2: Starting from the above \(P(H_0, M|d)\), approximate the integral \(P(H_0|d) = \int_{-\infty}^\infty dM P(H_0, M |d) \) with a discrete sum and produce a plot of \(H_0\) vs. \(P(H_0|d)\). Don't worry about the normalization of the probability density you plot.
18.3: Produce your own \(\Omega_m,\Omega_\Lambda\) 68\% and 95\% confidence contours using the Scolnic et al. (2018) data and, for simplicity, fixing M=-19.26 and \(H_0 = 72.9\) km/sec/Mpc. Ideally you would marginalize over these other variables, instead of fixing them, but that would be significantly more challenging. You can approximate the distributions as Gaussian (normal) for purposes of choosing the contour levels.


29.13.1: Review Questions
Review Questions
What are the basic observations about the universe that any theory of cosmology must explain?
2.
Describe some possible futures for the universe that scientists have come up with. What property of the universe determines which of these possibilities is the correct one?
3.
What does the term Hubble time mean in cosmology, and what is the current best calculation for the Hubble time?
4.
Which formed first: hydrogen nuclei or hydrogen atoms? Explain the sequence of events that led to each.
5.
Describe at least two characteristics of the universe that are explained by the standard Big Bang model.
6.
Describe two properties of the universe that are not explained by the standard Big Bang model (without inflation). How does inflation explain these two properties?
7.
Why do astronomers believe there must be dark matter that is not in the form of atoms with protons and neutrons?
8.
What is dark energy and what evidence do astronomers have that it is an important component of the universe?
9.
Thinking about the ideas of space and time in Einstein’s general theory of relativity, how do we explain the fact that all galaxies outside our Local Group show a redshift?
10.
Astronomers have found that there is more helium in the universe than stars could have made in the 13.8 billion years that the universe has been in existence. How does the Big Bang scenario solve this problem?
11.
Describe the anthropic principle. What are some properties of the universe that make it “ready” to have life forms like you in it?
12.
Describe the evidence that the expansion of the universe is accelerating.


10.2: Exercises
Lab 10 Exercise \(\PageIndex{1}\)
Identify the pats of a "neuron"
Lab 10 Exercise \(\PageIndex{2}\)
Label the following:
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Lab 10 Exercise \(\PageIndex{3}\)
Match these items or actions to their locations on a neuron: graded potentials, action
| 1 | graded potentials | 7 | EPSPs |
| 2 | action action | 8 | IPSPs |
| 3 | neurotransmitter-filled vesicles | 9 | pre-synaptic membrane |
| 4 | neurotransmitter receptors | 10 | post-synaptic membrane |
| 5 | voltage-gated sodium channels | 11 | Genes (that encode receptor proteins) |
| 6 | ligand-gated ion channels |
Lab 10 Exercise \(\PageIndex{4}\)
Label the following glia & related items:
| 1 | Astrocyte | 6 | Cerebrospinal fluid (CSF) |
| 2 | Perivascular feet | 7 | Extracellular fluid (ECF) |
| 3 | Oligodendrocyte | 8 | Neuron |
| 4 | Microglia | 9 | Capillary |
| 5 | Ependymal cell |
Lab 10 Exercise \(\PageIndex{5}\)
Label the histological sections
Lab 10 Exercise \(\PageIndex{6}\)
Obtain slides of each of the following tissues, observe them, draw and label the significant features. SLIDES: Spinal cord, cerebral cortex, cerebellum, dorsal root ganglion, peripheral nerve, neuromuscular junction:
1. Obtain a slide of nervous tissue from the slide box. Use any nervous tissue except peripheral nerve, there are no nerve cell bodies in a peripheral nerve section.
2. View the slide on the second-highest objective. Search carefully until you find a clear, representative neuron in your field of view.
3. In the circle below, draw the neuron you found. Only draw the single neuron. Do not draw any of the other material. Draw your structures proportionately to their size in your microscope’s field of view.
4. Label any neural parts you can clearly recognize.
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Total Magnification: _________________ Source of tissue: ____________________
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29.7: Review Questions
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- Last updated
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1.
What is the most appropriate intervention for the school nurse to implement to promote a healthy school environment?
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Advocate for nutritious school lunch programs
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Provide care for children with asthma
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Develop individualized health plans
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Educate students and families about screening for scoliosis
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Which action should the school nurse perform to address dental health at the community level?
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Educate caregivers of children with dental caries about oral health
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Advocate for fluoridation of drinking water
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Assist caregivers with finding dental resources for children without dental insurance
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Teach children in school how to floss properly
3.
Which function would the public health nurse perform while working at a local health department?
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Teaching a client how to self-inject insulin
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Implementing Medicaid regulations
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Educating a community about influenza vaccinations
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Regulating the Children’s Health Insurance Programs (CHIPs)
4.
What principle of correctional health care did the 1976 ruling in
Estelle v. Gamble
establish?
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Accreditation for correctional health care facilities
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Health information privacy for individuals in custody
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Autonomy over health care decisions for incarcerated people
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The provision of health care for incarcerated people
5.
Which concept should the nurse use when providing care for individuals who are incarcerated?
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Education levels of the incarcerated population are the same as the general population.
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There is a lack of privacy when caring for incarcerated people.
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Therapeutic nurse-client relationships are not utilized in correctional nursing.
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Most incarcerated people are middle-age or older adults.
6.
Which intervention can the nurse implement to reduce the spread of infectious disease in a correctional facility?
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Encouraging daily handwashing
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Asking about HIV status at intake to a correctional setting
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Questioning people about sexual practices
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Advocating for vaccination for hepatitis A and hepatitis B
7.
A school nurse is preparing a presentation to the school board on the scope of practice of the school nurse. Which information will the nurse present?
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The school district’s job description for the school nurse overrides the Nurse Practice Act.
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The Nurse Practice Act is a state law that determines the scope of practice for the school nurse.
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The scope of nursing practice for the school nurse is the same in every state.
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The state medical board decides the scope of practice for the school nurse in each state.
8.
Which action by the occupational health nurse is a secondary prevention activity?
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Screening for hearing loss
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Conducting safety inspections of work areas and facilities
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Educating employees to wear eye protection
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Completing a physical assessment after an injury
9.
Which workplace condition will the occupational health nurse include when teaching factory employees about ergonomic hazards?
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Repetitive motions
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Infectious agents
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Noise levels
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Cleaning solutions
10.
Which activity would the correctional nurse implement to address tertiary health promotion in individuals with long-term disease who are incarcerated?
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Teach rescue inhaler use for people with asthma
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Administer medication for the treatment of hepatitis C
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Advocate for low-sodium dietary options for people with hypertension
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Recommend physical therapy for people with arthritis


10.2: Polyethylene - From the Battle of Britain to Bread Bags
- List the different types of polyethylene.
- Differentiate between thermolastic and thermosetting polymers.
Polyethylene was first synthesized by the German chemist Hans von Pechmann, who prepared it by accident in 1898. Industrial production of low-density polyethylene (LDPE) began in 1939 in England. Because polyethylene was found to have very low-loss properties at very high frequency radio waves, commercial distribution in Britain was suspended on the outbreak of World War II in order to produce insulation for UHF (ultra high frequency) and SHF (super high frequency) cables of radar sets.
Polyethylene or polythene is the most common plastic. As of 2017, over 100 million tonnes of polyethylene resins are produced annually, accounting for 34% of the total plastics market. Its primary use is in packaging (plastic bags, plastic films, geomembranes, containers including bottles, etc.). Many kinds of polyethylene are known, with most having the chemical formula (C 2 H 4 ) n . PE is usually a mixture of similar polymers of ethylene with various values of n .
Polymers based on skeletons with only carbon are all synthetic. Let's begin by looking at polyethylene Figure \(\PageIndex{1}\) . It is the simplest polymer, consisting of random-length (but generally very long) chains made up of two-carbon units.
You will notice some "fuzziness" in the way that the polyethylene structures are represented above. The squiggly lines at the ends of the long structure indicate that the same pattern extends indefinitely. The more compact notation on the right shows the minimal repeating unit enclosed in brackets overprinted with a dash; this means the same thing and is the preferred way of depicting polymer structures.
Types of Polyethylene
Most of synthetic polymers are formed from ethylene. The relative lengths of the chains and any branches control the properties of polyethylene. The most important polymer grades with regard to volume are High density polyethylene (HDPE) Low density polyethylene (LDPE), and Linear low density polyethylene (LLDPE).
HDPE (High density polyethylene) is defined by a density of greater or equal to 0.941 g/cm 3 . HDPE has a low degree of branching. The mostly linear molecules pack together well, so intermolecular forces are stronger than in highly branched polymers. HDPE has high tensile strength. It is used in products and packaging such as milk jugs, detergent bottles, butter tubs, garbage containers, and water pipes. One-third of all toys are manufactured from HDPE. In 2007, the global HDPE consumption reached a volume of more than 30 million tons.
LDPE (Low density polyethylene) is defined by a density range of 0.910–0.940 g/cm 3 . LDPE has a high degree of short- and long-chain branching, which means that the chains do not pack into the crystal structure as well. It has, therefore, less strong intermolecular forces as the instantaneous-dipole induced-dipole attraction is less. This results in a lower tensile strength and increased ductility. The high degree of branching with long chains gives molten LDPE unique and desirable flow properties. LDPE is used for both rigid containers and plastic film applications such as plastic bags and film wrap. In 2013, the global LDPE market had a volume of almost US$33 billion.
LLDPE (Linear low density polyethylene) is defined by a density range of 0.915–0.925 g/cm 3 . LLDPE is a substantially linear polymer with significant numbers of short branches. LLDPE has higher tensile strength than LDPE, and it exhibits higher impact and puncture resistance than LDPE. Lower thickness (gauge) films can be blown, compared with LDPE, with better environmental stress-cracking resistance, but is not as easy to process. LLDPE is used in packaging, particularly film for bags and sheets. Lower thickness may be used compared to LDPE. It is used for cable coverings, toys, lids, buckets, containers, and pipe. While other applications are available, LLDPE is used predominantly in film applications due to its toughness, flexibility, and relative transparency. Product examples range from agricultural films, Saran wrap, and bubble wrap, to multilayer and composite films. In 2013, the world LLDPE market reached a volume of US$40 billion.
Video \(\PageIndex{1}\) The c ommercial production of Polyethylene (polyethene). from the Royal Society of Chemistry
Thermoplastic and Thermosetting Polymers
Polymers can be classified by their physical response to heating. Polyethylene is a thermoplastic; however, it can become a thermoset plastic when modified (such as cross-linked polyethylene). Thermoplastics are plastics that soften when heated and become firm again when cooled. This is the more popular type of plastic because the heating and cooling may be repeated and the thermoplastic may be reformed.
Thermosets are plastics that soften when heated and can be molded, but harden permanently. They will decompose when reheated. An example is Bakelite, which is used in toasters, handles for pots and pans, dishes, electrical outlets and billiard balls.
Summary
Polyethylene is the long chain polymer formed from ethylene (ethene) monomers.
Polyethylene can be classified as HDPE, LDPE, and LLDPE based on how close the polymer chains pack together affecting its density.
Polymers can be classified as thermoplastics (can be reformed after repeated heating) or thermosets (harden permanently) based on their physical response to heating.
Contributors and Attributions
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Stephen Lower, Professor Emeritus ( Simon Fraser U. ) Chem1 Virtual Textbook
- Charles Ophardt, Professor Emeritus, Elmhurst College; Virtual Chembook
- Wikipedia


1.24.2: Windows Store
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You can purchase and install applications from the Microsoft Windows Store, which is an application that is pre-installed in Windows 10. You can find applications to download in the Windows store by viewing applications by category or searching for the application of your choice. You may need to create/use a Microsoft Account and link your credit card information to your Microsoft Account to download applications. In the Windows Store, there are a variety of free and paid applications to download. Purchased applications can be downloaded on up to 10 other computers if the user is signed in with the same user account. Users can automatically update applications that have updates available in the Windows store.


2.1.9: The Oceans
It's obvious why Earth is called the "Blue Planet" as 71 percent of the surface is covered by water, 97% of which is in oceans. Oceans appeared on Earth between 3 and 4 billion years ago from which sprang life. Ancient algal formations found in the water near Australia called stromatolites are thought to have been the early source for oxygen in the atmosphere.
Oceans & Seas
Five principal oceans the Pacific, Atlantic, Indian, Southern and Arctic comprise the "world ocean" that surround the Earth's continental land masses. The Pacific Ocean is the largest covering 166 million square kilometers (64 million square miles) of the surface with an average depth of 4200 meters (14,000 ft). At nearly half the size, the Atlantic Ocean occupies 83 million square kilometers (32 million square miles) with an average depth of 3900 meters (13,000 ft). With a similar average depth, the Indian Ocean is slightly smaller at approximately 73 million square kilometers (28 million square miles). The Southern Ocean surrounds Antarctica and was recognized in 2000 as an ocean by the International Hydrographic Organization. It encompasses roughly 20.3 million square kilometers (7.8 million square miles) with a typical depth between 4,000 and 5,000 meters (13,000 to 16,000 feet). The Arctic Ocean is the smallest covering 13 million square kilometers (5 million square miles) with an average depth of 930 meters (3250 ft). Some view the Arctic Ocean as a sea rather than ocean because of its small size.
Seas are salt-water bodies smaller than oceans and partially enclosed by land. Major seas include the Mediterranean, Baltic, Bering, Black, Caribbean, Coral, North, Red, and Yellow. Unlike inland lakes that can be salt or fresh water, there is a constant exchange of water between ocean and sea. Several inland salt lakes like the Aral, Caspian, and Dead are erroneously named "seas".
The Nature of Ocean Water
Sea water makes up the largest store of water in the hydrologic cycle. It is comprised of nearly 60 chemical substances with common salt being the most abundant, 78% of the dissolved solids. Ocean salinity varies from 32 - 37 parts per thousand. Salinity is lower near land and in the polar regions (30 ppt).
A number of factors determine ocean salinity. Salinity is lower where freshwater rivers enter the ocean. In the North Pacific precipitation exceeds evaporation thus diluting ocean water. Water is more saline in subtropical oceans where evaporation exceeds precipitation. The Atlantic ocean is the most salty while the Arctic ocean is the least.
The oceans exhibit three vertical temperature zones, 1) a surface layer of water, 2) a transition zone of decreasing temperatures with depth, and 3) the cold waters of the deep ocean. The zone of transition, known as the thermocline, is most noticeable where surface water is warmest. Polar water may have no thermocline as the surface temperature are very cold.
Learn more about the impact of human activities on ocean water by Digging Deeper: Ocean Acidification, or continue to the next topic.
Oceans play an important role in the natural cycling of carbon dioxide through the Earth System (See: The Carbon Cycle). But the chemistry of the Earth's oceans is changing as a result of the absorption of anthropogenic carbon dioxide emissions. The ocean's absorb about 25% of the carbon dioxide released from human activities each year. The result is a decrease in pH and acidification of ocean water leading to severe consequences for ocean ecosystems.
How ocean acidification happens
When carbon dioxide (CO 2 ) combines with ocean (H 2 O) it forms H 2 CO 3 , carbonic acid. Most of this acid dissociates into hydrogen ions (H+) and bicarbonate ions (HCO 3 -1). The increase in H+ ions reduces pH and raising the acidity of ocean water. Since the dawn of the industrial revolution, which was fueled by fossil fuel burning, the pH of Earth's oceans has decreased from 8.2 to 8.1. This doesn't sound like much, but realize that pH is measured on a logarithmic scale. The .1 change represents a 30% increase in acidity. This increase is 100 times faster than any change in acidity for at least the last 20 million years. Under current emission rates, pH will fall by 0.4 between now and 2100, a 3-fold increase in acidity.
Impacts of ocean acidification
The impact of acid acidification is wide ranging and potentially disastrous for the earth system. Ocean acidification causes or is linked to various impacts on the ocean and its ecosystems. Some of these are:
- Decreasing uptake of atmospheric carbon dioxide as saturation level is approached. Like other elements dissolved in a solution, water has a saturation point beyond which its "sink function" ceases to be effective at absorbing carbon dioxide. As a result, more CO2 is left in the atmosphere to fuel global warming.
- Damage to coral reef ecosystems. Coral reefs are found in two types of ocean habitat, warm water and cold water. Warm water coral reef are typically found at shallow depths and in tropical waters. Cold-water corals are found at much deeper depths and in subtropical to high latitude oceans. Ocean acidification has been shown to hinder the calcification of deep-sea, or cold-water, corals. It is estimated that by 2100, 70% of cold-water corals will be exposed to acidified ocean water. Though excessively warm water is often the cause, acidified ocean water has been linked to coral bleaching. The whitening caused by bleaching occurs when corals lose microscopic algae within their tissues that give corals their wonderful colors.
- Slower growth rates for marine organisms with calcareous skeletons. As carbonic acid forms from the uptake of atmospheric CO2, the hydrogen ion concentration increases limiting access to carbonate ions needed to form shells.
- Disruption of marine food webs . Impacts on phytoplankton and other sensitive species may disrupt marine food webs and in turn affect fisheries. Phytoplankton are organisms that float on or near the surface of water. Most are single-celled, like diatoms and dinoflagellates,and in the ocean serve as the foundation of the marine food web. Phytoplankton are the primary producers of the ocean, accounting for 95% of the ocean's primary productivity. They serve as food for zooplankton that include copepods, some species of shrimp, and larval forms of jellyfish, barnacles, mollusks, and fish. Small predators like shrimp, krill, sardines, etc feed on the zooplankton, and are in turn eaten by large predators which include birds, large fish, and marine mammals. Loss of the species at the foundation reverberates through the entire food web. Soon, fisheries important to many national economies founder resulting in a degraded marine ecosystem.
Future ocean acidification
Ocean acidification is projected to increase this century as atmospheric carbon dioxide continues to increase. The amount of acidification depends largely on future emissions as shown by the Intergovernmental Panel on Climate Change projections for various emission scenarios. The worse case scenario for ocean acidification is one in which the world continues to use carbon-based energy resources to fuel its economic, industrial, and transportation needs.
Audio Program: Acid in the Oceans: A Growing Threat to Sea Life (Courtesy NPR - All Things Considered )
The Ocean Floor
The deep-ocean floor has an average depth of 4000 meters (12,000 feet) with a significant variation in the depth. The ocean basins are cut by deep trenches and large mountains rise from the floor. The midocean ridge is the longest continuous chain of mountains on Earth winding its way along the sea floor through all the oceans. Its width average 1600 kilometers (1000 mi) with ridges rising an average of 1500 - 3000 meters ( 5,000 - 10,000 feet) above the floor. Along its spine, new sea floor is created and spreads apart by lava pouring out of rifts along the ocean ridge. Along the rugged volcanic topography of the ridge one finds dramatic undersea volcanoes called " black smokers ".
Long narrow arc-shaped trenches cut across the deepest parts of the ocean floor. Trenches are found near active plate margins where earthquakes and volcanoes are common. Converging plates in subduction zones recycle rock along the ocean trenches. Ocean-flooring drilling along trenches and the midocean ridge indicates that rock is recycled over a period of 2 to 3 million years. The deepest trenches are found along the Pacific "Ring of Fire". Trenches are common along curved island arcs like the Aleutian Islands.
The vast submarine plains of the "ocean deep" are the abyssal plains. The abyssal plains cover 40% of the ocean floor with depths of 3000 - 6000 meters (10,000 - 20,000 ft). Wind deposition and volcanic eruptions have covered most in layers of brown and red clays. Some are covered with the remains of microscopic marine organisms known as ooze. The celebrated White Cliffs of Dover are uplifted ooze deposits.
Rising from the ocean floor one finds seamounts, mountains that do not reach the water's surface and typically formed from extinct volcanoes. Guyouts are flat-topped seamounts.
Continental Margins
The continental margins are comprised of three topographic features. The ocean floor slopes gradually upward toward the continents forming the continental rise . Approaching the edge of the continent the slope of the ocean floor steepens into the continental slope . At the top of the slope lies the continental shelf , a gently sloping platform of varying width. Along passive margins like the east coast of the United States, the continental shelf is wide. The continental shelf is much narrower along active margins bordered by mountains like that found along the west coast of the United States.


2.23: Comparing Genres
- Analyze characteristics from different genres of text
Below you’ll read excerpts from different types of sources. Before knowing much about the pieces, like who wrote them or where they were first published, consider what you learn about them just from these snippets.
Example 1
Example 1
“Electric and Plug-in Hybrids”
Learning Objectives
After reading this module, students should be able to
- outline the traditional dependence of transportation on oil and the internal combustion engine
- understand two alternatives to oil as a transportation fuel: hydrogen and electricity
- understand the dual use of oil and electricity in hybrid vehicles and their impact on energy efficiency and carbon emissions
Introduction
Since the early 20th Century, oil and the internal combustion engine have dominated transportation. The fortunes of oil and vehicles have been intertwined, with oil racing to meet the energy demands of the ever growing power and number of personal vehicles, vehicles driving farther in response to growing interstate highway opportunities for long distance personal travel and freight shipping, and greater personal mobility producing living patterns in far-flung suburbs that require oil and cars to function. In recent and future years, the greatest transportation growth will be in developing countries where the need and the market for transportation is growing rapidly. China has an emerging middle class that is larger than the entire population of the United States, a sign that developing countries will soon direct or strongly influence the emergence of new technologies designed to serve their needs. Beyond deploying new technologies, developing countries have a potentially large second advantage: they need not follow the same development path through outdated intermediate technologies taken by the developed world. Leapfrogging directly to the most advanced technologies avoids legacy infrastructures and long turnover times, allowing innovation and deployment on an accelerated scale.
Question for consideration:
As you read through the passage above, what distinguishing features about the text stand out to you?
[reveal-answer q=”484834″]Show Suggested Answer[/reveal-answer]
[hidden-answer a=”484834″]Features you noted might include:
- separate “Learning Objectives” and “Introduction” section
- use of the word “students” in Learning Objectives
- bulleted list in Learning Objectives
- hyperlink on phrase “internal combustion engine”
- long sentences
- complex and varied sentence structure
- formal tone
[/hidden-answer]
Example 2
Again, read through the excerpt below, which is the opening to a longer text. What do you notice while reading, without knowing much about the source overall?
Example 2
“Will the Tesla Model 3 recharge the U.S. electric vehicle market?”
Few product launches in recent memory have captured as much attention as last week’s unveiling of the Tesla Model 3 electric vehicle (EV), Tesla’s first vehicle pitched at the mass market.
Orders were flooding in even before Tesla CEO Elon Musk revealed the car to a giddy audience last Thursday evening, with prospective buyers queuing at Tesla stores throughout the day to place a deposit on a vehicle they might not even receive for two years or more.
Musk made the case for EVs being “ really important for the future of the world ,” combating rising greenhouse gas emissions and air pollution.
The Model 3 is really important for the future of Tesla and the future of EVs. It promises the sales growth that automotive wunderkind Tesla needs to survive and renews interest in a technology that is yet to have significant real-world impact. Yet even with the introduction of Tesla’s flashy new sedan, more pieces need to be in place before the EV market goes truly mainstream.
Battery prices dropping
When the Chevrolet Volt plug-in hybrid and Nissan Leaf battery-electric vehicle hit U.S. showrooms in December 2010, the price of gasoline was rising, and so were expectations for the future of EVs.
Shortly after, President Obama articulated the goal of having one million EVs on U.S. roads by 2015, and committed billions of investment in EV manufacturing capacity, recharging infrastructure deployment and vehicle purchase incentives.
Question for consideration:
As you read through the passage above, what distinguishing features about the text stand out to you?
[reveal-answer q=”870382″]Show Suggested Answer[/reveal-answer]
[hidden-answer a=”870382″]Features you noted might include:
- title is in the form of a question
- seems to focus on current events
- short paragraphs, often only 1 sentence long
- sentences are fairly long and complex
- two hyperlinked phrases
- section header, “Battery Prices Dropping”
- formal tone
[/hidden-answer]
Example 3
Example 3
“Cannibalism in the Cars”
I visited St. Louis lately, and on my way West, after changing cars at Terre Haute, Indiana, a mild, benevolent-looking gentleman of about forty-five, or maybe fifty, came in at one of the way-stations and sat down beside me. We talked together pleasantly on various subjects for an hour, perhaps, and I found him exceedingly intelligent and entertaining. When he learned that I was from Washington, he immediately began to ask questions about various public men, and about Congressional affairs; and I saw very shortly that I was conversing with a man who was perfectly familiar with the ins and outs of political life at the Capital, even to the ways and manners, and customs of procedure of Senators and Representatives in the Chambers of the national Legislature. Presently two men halted near us for a single moment, and one said to the other:
“Harris, if you’ll do that for me, I’ll never forget you, my boy.”
My new comrade’s eye lighted pleasantly. The words had touched upon a happy memory, I thought. Then his face settled into thoughtfulness—almost into gloom. He turned to me and said,
“Let me tell you a story; let me give you a secret chapter of my life—a chapter that has never been referred to by me since its events transpired. Listen patiently, and promise that you will not interrupt me.”
I said I would not, and he related the following strange adventure, speaking sometimes with animation, sometimes with melancholy, but always with feeling and earnestness.
Question for consideration:
As you read through the passage above, what distinguishing features about the text stand out to you?
[reveal-answer q=”915485″]Show Suggested Answer[/reveal-answer]
[hidden-answer a=”915485″]Features you noted might include:
- has an unusual, interesting title
- uses first-person pronoun (“I”)
- includes dialogue
- uses old-fashioned language
- tells a story
- introduces characters
[/hidden-answer]
Example 4
Example 4
“Hybrid Vehicle”
A hybrid vehicle uses two or more distinct types of power, such as internal combustion engine+electric motor, [1] e.g. in diesel-electric trains using diesel engines and electricity from overhead lines, and submarines that use diesels when surfaced and batteries when submerged. Other means to store energy include pressurized fluid, in hydraulic hybrids .
Heavy vehicles
Hybrid power trains use diesel-electric or turbo-electric to power railway locomotives, buses, heavy goods vehicles, mobile hydraulic machinery, and ships. A diesel/turbine engine drives an electric generator or hydraulic pump, which powers electric/hydraulic motor(s) – strictly an electric/hydraulic transmission (not a hybrid), unless it can accept power from outside. With large vehicles conversion losses decrease, and the advantages in distributing power through wires or pipes rather than mechanical elements become more prominent, especially when powering multiple drives — e.g. driven wheels or propellers. Until recently most heavy vehicles had little secondary energy storage, e.g. batteries/hydraulic accumulators — excepting non-nuclear submarines, one of the oldest production hybrids, running on diesels while surfaced and batteries when submerged. Both series and parallel setups were used in WW2 submarines.
Question for consideration:
As you read through the passage above, what distinguishing features about the text stand out to you?
[reveal-answer q=”785537″]Show Suggested Answer[/reveal-answer]
[hidden-answer a=”785537″]Features you noted might include:
- two alternative suggestions for reading at the top
- several hyperlink text phrases
- use of footnotes
- phrase “hybrid vehicle” in bold
- formal tone
- technical language
- section header, “Heavy vehicles”
- historical and present-day information
[/hidden-answer]
Example 5
One last time, read through the excerpt below. What do you notice while reading, without knowing much about the source overall?
Example 5
“ The Influence of Intersections on Fuel Consumption in Urban Arterial Road Traffic: A Single Vehicle Test in Harbin, China”
Abstract
The calculating method for fuel consumption ( FC ) was put forward and calibrated and the characteristics of the fuel consumption on intersections were analyzed based on 18 groups of vehicular operating data which were acquired from the test experiment of a single vehicle along the urban arterial roads in Harbin, China. The results obtained show that 50.36% of the fuel consumption for the test vehicle was used at the area of intersections compared with 28.9% of the influencing distance and 68.5% of the running time; and 78.4% of them was burnt at the stages of acceleration and idling. Meanwhile, the type (c) of the vehicular operating status was illustrated to be the worst way of reducing fuel consumption, the causes were analyzed and four improvement strategies were put forward.
Introduction
Statistically, one-third of the gasoline was exhausted by autos worldwide each year; and energy supply had become one of huge challenges for human beings. Consequently, 3 main fuel consumption reduction technologies were put forward and implemented from the aspects of vehicles, driving behaviors and traffic management and control respectively. Above all, advanced engine technologies, which were usually improved by auto makers and researchers, were gradually applied including hybrid electric engine, and turbocharger technology. For instance, hybrid electric vehicles (HEVs) or plug-in hybrid electric vehicles (PHEVs) were proved to be successful to reduce the fuel consumption; many relative strategies and methods were proposed to save the HEVs fuel consumption. Hu et al . and Yang et al . addressed the electrochemical energy buffers and robust coordinated control applied for the HEVs separately and the results showed that the proposed strategy could improve the fuel economy [ 1 , 2 ]. Hu et al . and Li et al . discussed the two optimization-based and dynamic programming-based global optimal energy management strategies for the plug-in hybrid electric bus (PHEBs) [ 3 , 4 ]; Sun et al . developed a PHEVs energy management algorithm to achieve enhanced fuel economy under different traffic flow information conditions [ 5 ]. Zheng et al . analyzed the effect of battery temperature on fuel consumption of fuel cell hybrid vehicles (FCHVs) [ 6 ]; Hu et al . discussed the optimal dimensioning or longevity-conscious dimensioning and power management for the fuel cell hybrid buses (FCHBs) with the method of convex programming and the findings showed that they are optimal and efficient [ 7 , 8 ]. Meanwhile, stop-start technology (STT) can save about 5~15% fuel consumption [ 9 ]; and the turbocharger technology can also reduce fuel consumption for the vehicles and be used widely.
Question for consideration:
As you read through the passage above, what distinguishing features about the text stand out to you?
[reveal-answer q=”948704″]Show Suggested Answer[/reveal-answer]
[hidden-answer a=”948704″]Features you noted might include:
- long title, with a colon indicating a subtitle
- has an abstract and introduction section
- technical language, with abbreviations for common terms like (FA)
- includes percentages and statistics
- footnotes and in-text citations
- formal tone
- long, complex sentences and paragraphs
[/hidden-answer]
Contributors and Attributions
- Introduction and Your Observations. Provided by : Lumen Learning. License : CC BY: Attribution
- Electric and Plug-in Hybrids. Authored by : George Crabtree. Provided by : OpenStax CNX. Located at : http://cnx.org/contents/I5_uSFCt@2/Electric-and-Plug-in-Hybrids . License : CC BY: Attribution
- Will the Tesla Model 3 recharge the U.S. electric vehicle market?. Authored by : David Keith. Provided by : The Conversation. Located at : http://theconversation.com/will-the-tesla-model-3-recharge-the-u-s-electric-vehicle-market-57171 . License : CC BY-ND: Attribution-NoDerivatives
- Hybrid Vehicle. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Hybrid_vehicle. License : CC BY-SA: Attribution-ShareAlike
- The Influence of Intersections on Fuel Consumption in Urban Arterial Road Traffic: A Single Vehicle Test in Harbin, China. Authored by : Lina Wu, Yusheng Ci , Jiangwei Chu, and Hongsheng Zhang. Provided by : PLoS One. Located at : http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0137477 . License : CC BY: Attribution
- Image of a parking garage. Authored by : Bilderandi. Provided by : Pixabay. Located at : pixabay.com/photos/autos-technology-vw-214033/. License : Other . License Terms : pixabay.com/service/terms/#license
- Cannibalism in the Cars. Authored by : Mark Twain. Located at : http://www.gutenberg.org/files/3189/3189-h/3189-h.htm#cannibalism . License : Public Domain: No Known Copyright


1.7: Cross-Cultural Comparison and Cultural Relativism
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- Last updated
- Save as PDF
- Jennifer Hasty, David G. Lewis, & Marjorie M. Snipes
- OpenStax
Learning Objectives
By the end of this section, you will be able to:
- Define the concept of relativism and explain why this term is so important to the study of anthropology.
- Distinguish relativism from the “anything goes” approach to culture.
- Describe how relativism can enlighten our approach to social problems.
Recall our earlier discussion of cultural styles of clothing. American clothing style is related to American values. Ghanaian clothing style is related to Ghanaian values. We have seen how different realms of culture are interrelated, fitting together to form distinctive wholes. Anthropologists use the term cultural relativism to describe how every element of culture must be understood within the broader whole of that culture. Relativism highlights how each belief or practice is related to all of the other beliefs and practices in a culture. The anthropological commitment to relativism means that anthropologists do not judge the merits of particular beliefs and practices but rather seek to understand the wider contexts that produce and reinforce those elements of culture. Even when studying controversial topics such as piracy and guerilla warfare, anthropologists set aside their personal convictions in order to explore the complex web of cultural forces that determine why we do the things we do.
Relativism Is Not “Anything Goes”
Critics of the notion of relativism, believing so strongly in their own cultural norms that they cannot set them aside, even temporarily. They argue that relativism is amoral, a refusal to condemn aspects of culture considered to be wrong and harmful. For them, relativism means “anything goes.”
For anthropologists, cultural relativism is a rigorous mode of holistic analysis requiring the temporary suspension of judgment for the purposes of exploration and analysis. Anthropologists do not think that violent or exploitative cultural practices are just fine, but they do think that the reasons for those practices are a lot more complex than we might imagine. And frequently, we find that the judgmental interventions of ethnocentric outsiders can do more harm than good.
Morality, Activism, and Cultural Relativism
A striking example of the application of cultural relativism in anthropology is the controversy surrounding female genital cutting (FGC), sometimes called female genital mutilation. FGC is a cultural practice in which an elder cuts a younger woman’s genitalia, removing all or part of the clitoris and labia. The practice is common in parts of Africa and the Middle East. FGC is not only extremely painful; it can also lead to infection, urination problems, infertility, and complications in childbirth.
The World Health Organization and the United Nations condemn the practice as a form of violence against children, a danger to women’s health, and a violation of basic human rights. These organizations view FGC as a form of discrimination against women, enforcing extreme inequality among the sexes. Efforts to ban FGC have focused on educating parents and children about the medical harms associated with the practice.
Despite decades of campaigning against FGC, however, the practice remains widespread. If condemning FGC has not been effective in reducing it, then what can be done? Anthropologist Bettina Shell-Duncan has taken a more relativist approach, attempting to understand the larger cultural norms and values that make FGC such an enduring practice. Setting aside her personal opinions, Shell-Duncan spent long periods in African communities where FGC is practiced, talking to people about why FGC is important to them. She learned that FGC has different functions in different sociocultural contexts. Among the Rendille people of northern Kenya, many people believe that men’s and women’s bodies are naturally androgynous, a mix of masculine and feminine parts. In order for a girl to become a woman, it is necessary to remove the parts of female genitalia that resemble a man’s penis. Likewise, in order for a boy to become a man, the foreskin must be removed because it resembles the folds of female genitalia.
Other societies value FGC for different reasons. Some Muslim societies consider FGC a form of hygiene, making a girl clean so that she can pray to Allah. Some communities see FGC as a way of limiting premarital sex and discouraging extramarital affairs. In the colonial period, when FGC was banned by the colonial government, some Kenyan girls practiced FGC on themselves as a form of resistance to colonial authority. As FGC is promoted and carried out by senior women in most contexts, the practice becomes a way for senior women to solidify power and exert influence in the community.
People in communities practicing FGC are often aware of the efforts of outside groups to ban the practice. They know about medical complications such as the risk of infection. But the denunciations of outsiders often seem unconvincing to them, as those denunciations tend to ignore the cultural reasons for the endurance of FGC. People who practice FGC do not do it because they despise women or want to harm children. Shell-Duncan argues that parents weigh the risks and benefits of FGC, often deciding that the procedure is in the best interest of their child’s future.
Personally, Shell-Duncan remains critical of FGC and works on a project with the Population Council designed to dramatically reduce the practice. Cultural relativism does not mean permanently abandoning our own value systems. Instead, it asks us to set aside the norms and values of our own culture for a while in order to fully understand controversial practices in other cultures. By suspending judgment, Shell-Duncan was able to learn two important things. First, while campaigns to eradicate FGC frequently target mothers, providing them with educational material about the medical risks involved, Shell-Duncan learned that the decision to go ahead with the procedure is not made by parents alone. A large network of relatives and friends may pressure a girl’s parents to arrange for the cutting in order to ensure the girl’s chastity, marriageability, and fertility. Secondly, Shell-Duncan learned that people who practice FGC do it because they want the best for their girls. They want their girls to be respected and admired, considered clean and beautiful, fit for marriage and childbearing.
Shell-Duncan argues that outside organizations should reconsider their efforts, focusing more on communities than on individual parents. Awareness campaigns will be more effective if they resonate with local norms and values rather than dismissively condemning them as part of the whole culture of FGC. Some researchers urge anti-FGC activists to connect with local feminists and women’s groups in an effort to empower local women and localize the movement against FCG. Some alternative approaches press for more incremental forms of change, such as moving the practice to more sanitary conditions in clinics and hospitals and reducing the severity of the procedure to smaller cuts or more symbolic nicks.
As this example illustrates, cultural relativism is not an amoral “anything goes” approach but rather a strategy for forming cross-cultural relationships and gaining deeper understanding. Once this foundation has been established, anthropologists are often able to revise their activist goals and more effectively work together with people from another culture in pursuit of common interests.