3.2: Health Effects of Drug Abuse
In addition to the effects various drugs of abuse may have on specific organs of the body, many drugs produce global body changes such as dramatic changes in appetite and increases in body temperature, which may impact a variety of health conditions. Withdrawal from drug use also may lead to numerous adverse health effects, including restlessness, mood swings, fatigue, changes in appetite, muscle and bone pain, insomnia, cold flashes, diarrhea, and vomiting.
Marijuana
Marijuana is made from the hemp plant, Cannabis sativa . The main psychoactive (mind-altering) chemical in marijuana is delta-9-tetrahydrocannabinol, or THC.
| Possible Health Effects | |
|---|---|
| Short-term | Enhanced sensory perception and euphoria followed by drowsiness/relaxation; slowed reaction time; problems with balance and coordination; increased heart rate and appetite; problems with learning and memory; hallucinations; anxiety; panic attacks; psychosis. |
| Long-term | Mental health problems, chronic cough, frequent respiratory infections. |
| Other Health-related Issues |
Youth: possible loss of IQ points when repeated use begins in adolescence. Pregnancy: babies born with problems involving attention, memory, and problem solving. |
Cocaine
A powerfully addictive stimulant drug made from the leaves of the coca plant native to South America.
| Possible Health Effects | |
|---|---|
| Short-term | Narrowed blood vessels; enlarged pupils; increased body temperature, heart rate, and blood pressure; headache; abdominal pain and nausea; euphoria; increased energy, alertness; insomnia, restlessness; anxiety; erratic and violent behavior, panic attacks, paranoia, psychosis; heart rhythm problems, heart attack; stroke, seizure, coma. |
| Long-term | Loss of sense of smell, nosebleeds, nasal damage and trouble swallowing from snorting; infection and death of bowel tissue from decreased blood flow; poor nutrition and weight loss from decreased appetite. |
| Other Health-related Issues |
Pregnancy: premature delivery, low birth weight, smaller head circumference. Risk of HIV, hepatitis, and other infectious diseases from shared needles. |
Methamphetamine
An extremely addictive stimulant amphetamine drug.
| Possible Health Effects | |
|---|---|
| Short-term | Increased wakefulness and physical activity; decreased appetite; increased breathing, heart rate, blood pressure, temperature; irregular heartbeat. |
| Long-term | Anxiety, confusion, insomnia, mood problems, violent behavior, paranoia, hallucinations, delusions, weight loss, severe dental problems (“meth mouth”), intense itching leading to skin sores from scratching. |
| Other Health-related Issues |
Pregnancy: premature delivery; separation of the placenta from the uterus; low birth weight; lethargy; heart and brain problems. Risk of HIV, hepatitis, and other infectious diseases from shared needles. |
CNS Depressants
CNS depressants slow down brain activity and can cause sleepiness and loss of coordination. Continued use can lead to physical dependence and withdrawal symptoms if use is stopped.
| Possible Health Effects | ||||
|---|---|---|---|---|
| Short-term | Drowsiness, slurred speech, poor concentration, confusion, dizziness, problems with movement and memory, lowered blood pressure, slowed breathing. | |||
| Long-term | Physical dependence, withdrawal, possibility of seizures from rebound effect. | |||
| Other Health-related Issues |
Sleep medications are sometimes used as date rape drugs (e.g. Rohypnol). Risk of HIV, hepatitis, and other infectious diseases from shared needles. |
|||
| In Combination with Alcohol | Further slows heart rate and breathing, which can lead to death. |
Prescription Opioids
Pain relievers with an origin similar to that of heroin. Opioids can cause euphoria and are often used nonmedically, leading to overdose deaths.
| Possible Health Effects | |
|---|---|
| Short-term | Pain relief, drowsiness, nausea, constipation, euphoria, confusion, slowed breathing, death. |
| Long-term | Physical dependence, possible brain damage. |
| Other Health-related Issues |
Pregnancy: Miscarriage, low birth weight, neonatal abstinence syndrome. Older adults: higher risk of accidental misuse or abuse because many older adults have multiple prescriptions, increasing the risk of drug-drug interactions, and breakdown of drugs slows with age; also, many older adults are treated with prescription medications for pain. Risk of HIV, hepatitis, and other infectious diseases from shared needles. |
| In Combination with Alcohol | Dangerous slowing of heart rate and breathing leading to coma or death. |
Heroin
| Possible Health Effects | |
|---|---|
| Short-term | Euphoria; warm flushing of skin; dry mouth; heavy feeling in the hands and feet; clouded thinking; alternate wakeful and drowsy states; itching; nausea; vomiting; slowed breathing and heart rate. |
| Long-term | Collapsed veins; abscesses (swollen tissue with pus); infection of the lining and valves in the heart; constipation and stomach cramps; liver or kidney disease; pneumonia. |
| Other Health-related Issues |
Pregnancy: miscarriage, low birth weight, neonatal abstinence syndrome. Risk of HIV, hepatitis, and other infectious diseases from shared needles. |
| In Combination with Alcohol | Dangerous slowdown of heart rate and breathing, coma, death. |
Click here to learn more about heroin and opioid abuse.
- Commonly Abused Drugs. Authored by : National Institute on Drug Abuse. Provided by : National Institutes of Health. Located at : https://www.drugabuse.gov/drugs-abuse/commonly-abused-drugs-charts#marijuana . License : Public Domain: No Known Copyright
- Drug Facts. Authored by : National Institute on Drug Abuse. Provided by : National Institutes of Health. Located at : https://www.drugabuse.gov/publications/finder/t/160/DrugFacts . License : Public Domain: No Known Copyright


4.7: Cross-Cultural Communication
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LEARNING OUTCOMES
- Practice cross-cultural communication through communication competence.
- Understand how to learn about cultures.
- Discuss international cultures co-existing within communities.
- Analyze problems within cross-cultural communication.
- Understand cultural issues and perception within multiple types of relationships.
- Understand the effect of age, generation, race, gender, and disability in cultural communication.
CROSS-CULTURAL COMMUNICATION
Communicating across cultures
When people from different cultures communicate, this is cross-cultural communication. This can be people from different families, different occupations, different races, ages, and genders. It can also be cross-cultural communication when two people are from different countries.
What is needed in cross-cultural communication is competence, and this comes partially from having an open mind. Critical thinking is necessary to ascertain what these differences are, and how to get the point across in a different way, or at least be able to explain the why. Chung notes the rapidly changing demographics in the United States, saying, “what was once a homogeneous community, we may now find more diversity and cultural values in flux” and that we learn more from people who are different than people who are similar (2019, p. 376). There’s value in diversity.
An example of cross-cultural communication is when a couple comes together and they are from different cultures, i.e. a person from Houston, Texas, gets together with another person from near Houston, Texas, but who is originally from Lima, Peru, by way of Brazil. There may be a nuanced language barrier, or a difference in food expectations, and a difference in expected dinner times. These partners may have the same religion, and so there is that in common.
But, families communicate differently, so they must negotiate their norms nonverbally and verbally. For instance, the Peruvian hugs and has more communication through touch. There may be differences in expectations for how to raise children, household chores, and who works and who doesn’t. There may also be questions if there is a lack of competence of one or both of the people involved. The initial attraction may be physical, but there would be a lot of interpretation going on in actions.
Competence and cultural learning
How we learn about other cultures may improve our competence level. Many people will simply begin to ask questions, or may do research on the particular culture of the person. Knowing that the research is about a group of people should be telling, as all people from within a culture will not be the same. However, reaching out shows outreach.
Food is a great way to find out about a culture, and the treatment of food. Many families in the United States rarely have dinner together, and instead fend for themselves, while other families insist upon a family dinner at one table with no electronics every night. Some people will want everyone to eat all the food, where some people will want some food to be left on the plate. This is something that must be learned.
Within communities, there may be many people from different countries, and there is a need to learn the norms. Consider a real estate agent who is a white woman from Texas and who is invited to a client’s baby shower. The client is from Nigeria, and the real estate agent budgeted only 45 minutes of time for the shower. The real estate agent showed up at the designated time, was there for almost two hours. The client showed up right as she was leaving. The real estate agent was confused, but hadn’t researched the culture. Time is viewed differently within the Nigerian culture, but the agent didn’t realize that would apply in the United States. However, with many Nigerian people at the party, the time standard was not typical U.S. time orientation.
Knowing our audience is important, so we become more competent. The best intercultural communicators are people who are genuinely interested in other cultures.
Problems in cross-cultural communication
Biases
Problems in cross-cultural communication can be stereotyping, ethnocentrism, prejudice, discrimination, and racism. Stereotyping , according to Hall, is “attributions that cover up individual differences and ascribe certain characteristics to an entire group of people” (2005, p. 192). An example might be that Asians are good at math. While this may be a positive stereotype, it’s still not correct to use, whether it’s positive or negative.
Ethnocentrism is “assuming that one’s group is the center of the world” and feelings of superiority (Hall, 2005, p. 198). Though ethnocentrism may not be meant to be negative, it shows a lack of critical thinking, and thinking outside the culture. The real estate agent from our earlier example who attended her Nigerian friend’s baby shower could have made the mistake of telling her friend that it’s better to have an exact start time for an event, but instead, the agent went along with the uncertainty even if it made the agent feel a bit out of her comfort zone.
Prejudice is “a rigid attitude that’s (1) based on group membership and (2) predisposes an individual to feel, think, or act in a negative way toward another person or group of persons.” (Hall, 2005, p. 202). Prejudice is always negative. Discrimination is acting negatively based on prejudice, while racism is discrimination or prejudice directed at someone of a different race because of the notion that one’s own race is superior. These get progressively more negative and harmful.
Rockson (2019) writes a primer on how to connect with others through cross-cultural communication, and suggests that people need to be aware of their own values and biases, as that helps prevent missteps and bad relationships. Rockson’s (2019) book suggests the solution is to educate, don’t perpetuate, and instead, communicate.
Relationships
On the positive side, cross-cultural relationships often develop. Relationships have many variations: strangers, acquaintances, friends, romantic partners, and family. The way all these relationships are valued varies between cultures. For instance, the elderly population of some cultures is treated differently than in other cultures, like Japan versus the United States. In Japan, 58% of elderly people are likely to live with one of their children, while in the United States, 15% of elderly people live with someone else, and Japanese elders are seen to have more wisdom and are listened to with reverence and seen as relevant (Karasawa, 2011).
Family relationships tend to be nuclear in the United States, though the saying “blood is thicker than water” has been heard in the country. This saying means that family relationships are more valued than other relationships. Within families, relationships within collectivist countries like Japan tend toward family members sticking with extended family members, even to the point of living in the same households.
When people immigrate to the United States, the tradition of extended family living together often carries over. For instance, Indian families often have multiple generations living together, as do Hispanic families from collectivist cultures. As economies change, these things may tend to change as well.
Within the United States, the culture of friendliness with strangers varies. In Southern states, there tends to be an air of friendliness, and strangers will help each other out, and go out of their way to do nice things, whereas in northern states, or larger cities, like New York City, people are not as conversational, and may not consider others as much. Neither is good or bad, they just are.
Acquaintances within cross-cultural relationships often co-exist, like one street in Houston, where there was a large Catholic family with five children, next door to a lesbian couple with two children, a black family with children, a couple with no children, an Indian family, and an Asian family. This particular community touted itself as the most international community in the world, and everyone coexisted, but no one seemed to truly involve themselves in each other’s lives.
With cross-cultural friends, more of an effort is made to reach out and maintain. With cross-cultural relationships, there may be a more difficult time understanding each other’s world views, but the variations in ethnicities, race, religion, and more can make things more interesting. An example would be a friendship in which one friend is an atheist, whereas the other is an evangelical Christian, or a friendship where one person is Catholic and the other person is Hindu. Even with that religious difference, it can be a learning opportunity.
Romantic partners may have the hardest time of all of these within cross-cultural relationships. Romantic partners of different backgrounds may need the goodwill or acceptance of their extended families, and sometimes may not receive it. For instance, an Indian-American Hindu woman marrying a Bangladeshi-born American Muslim man might encounter resistance from their families, but might persist. Or, the families could intervene and question them.
The video Working with Cross-Cultural Couples (2018) includes an example of an African American woman who married a West African Muslim man, and found that she had more in common with a white man from Colorado than she did with her own husband, though she and her husband both had similar skin tone. She experienced being called a “black white wife” by her husband’s family, as she is American. The video noted that the couple stayed married despite these issues.
The earlier Peruvian-American who married the several-generation Texan didn’t encounter reservations from family, but both encountered some need to be mindful about their respective families and expectations. For instance, the Peruvian mother-in-law moved to the house on the next street over, but maintained some distance instead of moving right into the couple’s house. The white Texan man learned to be more physically affectionate with the Peruvian in-laws, as is the norm.
Affection may be experienced differently within cross-cultural couples, and decisions need to be made about language and children, religion, and naming, and all of these things that may be negotiated along the way.
Improving cross-cultural relationships
When it comes to improving cross-cultural relationships, think about differences and similarities, and how those may cause both people within a relationship to react. Age and generational differences show up in family relationships, as an example, teenage children and their parents or grandparents may have differences of opinion.
They may place importance on different notions as well. Note, the “OK, Boomer” phenomenon from 2019. This phrase is used whenever younger people want to ignore or dismiss something a person of an older generation says. In current U.S. culture, there are several generations, starting with Generation Z, people who are currently very young up to about age 19 or so. These are people who have grown up with technology, unless their parents forbade it. Millennials, or Generation Y, are currently the young adults, on up to the late 30s. While they didn’t start out with technology, they’ve used it most of their lives, and it’s permeated their view of the world.
Generation X, or what was known as they were coming of age as the ‘Slacker Generation,’ is the generation in their 40s to early 50s currently. They are at the peak of their careers, and have learned to integrate technology into their lives. The Boomer generation is currently in their later 50s to early 70s, and they are retiring or continuing to work. The generation known as the Greatest Generation is aging, and definitely did not grow up with technology, but they are living longer than the generations before them. Age can be a factor in relating to people interpersonally, so think about topics of conversation and examples that are used, as those will vary greatly between generations.
People who are older will have different wording for dating, such as calling someone a beau or boyfriend, or will say, “are you going with someone?” or they may use the word “courting.” Teens will say, “I’m dating someone” or if it’s not “official” then “talking to someone.”
Racial differences also play a part of communication. What is important to think about with race relations is that race is still a big factor in many people’s minds, and it’s been in the news a lot lately. Sometimes people don’t communicate with people of different races because they haven’t experienced such friendships before, and so there is uncertainty.
Talk with people from different backgrounds, and ask about experiences. With people who are of different backgrounds, listen and then believe their experience, and understand privilege. Even things as simple as the emoji for a thumbs up tends to be first in a white skin tone, but brown skin tone emojis exist as well.
When you are within a culture, sometimes you may not notice these things, but take a look around. Seek out experience, and learn. Know that bias can creep into conversations, but understand that, apologize for it, and make a commitment to change behaviors.
Gender roles in different cultures may be unknown, and may be more pronounced, as discussed earlier in the masculine and feminine culture section. Think critically about the gender roles, and what you may see in others. Just because a woman takes on more traditionally feminine roles in a relationship doesn’t mean it’s bad, unless she doesn’t want to do those roles. An example is a new heterosexual couple watching a romantic movie for the first time together, and the male cries and the female doesn’t. Is this outside of what is seen as the norm? Perhaps, but is it wrong? Nope. Self-expression can come in different modes for people.
Disability as a factor in relationships can affect interpersonal communication. People with disabilities should be addressed as you would address anyone else. If someone has cerebral palsy, and uses a wheelchair and has an attendant with them to help facilitate communication, when you converse with the person, make eye contact with the person with the disability, not the attendant.
When someone with Down syndrome is ordering food at a restaurant, ask them what they want, not the other people they are with. Expect people with a disability to be able to function independently, until they ask for help. One time, a 10-year-old boy with Down syndrome surprised his parents by climbing out a window to go sit on the roof. They realized what he’d done, and knew to mitigate for that in the future, but learned that he could figure out how to do things they never imagined.
When someone who is blind is walking down the hall, don’t grab their arm to guide them. Rather, if it appears they could need help, ask if they need help. With a deaf person, make lots of eye contact, and feel free to write something down on paper if other ways of communicating aren’t working. Sign language interpreters often help in larger-group situations. If you know the person, try to learn American Sign Language (if that is what the person uses).
There are many different types of disabilities, including physical, developmental, intellectual, and learning disabilities. Sometimes people have a combination of these disabilities. People appreciate effort to communicate with them, and relationships with people with disabilities can be extremely rewarding for all involved. Chances are, all people have encountered someone with a disability in their educational journey.
LEARNING ACTIVITIES
Activity 1: Ethnocentrism and Mobility
Read the article “The Inevitability of Ethnocentrism Revisited: Ethnocentrism Diminishes As Mobility Increases,” located at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4672305/ . What does the article say about in-group and out-groups? How does mobility reduce out-group hostility? Does traveling help reduce ethnocentrism?
Activity 2: American Dream Quiz
A recent quiz was created about privilege to determine how many roadblocks people have encountered on their search for the American Dream. Do the quiz, located at https://movingupusa.com/calc/ . What was your score, and were you surprised? How many of the things that you consider roadblocks have been within your control?
REFERENCES
Chung, L. (2019). Crossing boundaries: Cross-cultural communication. In K. D. Keith (Ed.), Cross-cultural psychology: Contemporary themes and perspectives (pp. 400-420). Wiley.
Hall, E. T. (1976). Beyond Culture. Garden City, NY: Anchor Books/Doubleday.
Karasawa, M., Curhan, K. B., Markus, H. R., Kitayama, S. S., Love, G. D., Radler, B. T. & Ruff, C. D. (2011). Cultural perspectives on aging and well-being: A comparison of Japan and the U.S. Int J Aging Hum Dev . 73(1): Pp. 73–98.
Rockson, T. (2019). Use your difference to make a difference: How to connect and communicate in a cross-cultural world . Wiley.
Working with cross-cultural couples: Unexplored issues in therapy [Video file]. (2018). Retrieved February 8, 2020, from https://fod.infobase.com/PortalPlayl...55&xtid=183978
GLOSSARY
Discrimination: Treating someone differently because of characteristics such as race, age, or sex
Ethnocentrism: Thinking one’s own way of thinking or being is superior, without considering that it is negative, because of the difficulty of getting out of one’s own culture
Prejudice: Being negatively biased against someone because of characteristics such as race, age, or sex
Racism: Prejudice based on the belief that a person’s own race is superior
Stereotyping: Attributing generalized characteristics to an entire group of people
MEDIA
Multimedia 1: An intercultural couple discusses how they negotiate cultural differences. Particularly, a Japanese man and a white U.S. American woman discuss their differences.
What we argue about | Japanese/American marriage https://www.youtube.com/watch?v=V0reQCDL968
Multimedia 2: Comedian and news anchor Trevor Noah discusses trying a taco for the first time. More importantly, look at the misunderstanding that happens in the use of language in the clip. Think about whether you may have had misunderstandings like these with friends from other cultures.
Trevor Noah: That’s Racist - Tacos: https://www.youtube.com/watch?v=QDk5ajNDgZc&list=TLPQMTEwMTIwMjBTkibtm_xuXQ&index=2
Multimedia 3: Biracial actresses from Sister, Sister discuss their marriages. One of the twins is married to an African American man, and the other is married to a white man. Think about your own experience with interracial couples, or even your own experience being part of an interracial couple. How do you react when you hear such things? https://www.youtube.com/watch?v=ngwvHYqYGS0
Multimedia 4: Observe the following clip to see how different cultures view cultural appropriation. How will you react differently, if at all, to costumes in the future?
My Culture is NOT a Costume: Cultural Appropriation https://www.youtube.com/watch?v=d6Y5cARFJw8


6.2: Temperature
Generally ocean temperatures range from about -2 o to 30 o C (28-86 o F). The warmest water tends to be surface water in low latitude regions, while the surface water at the poles is obviously much colder (Figure \(\PageIndex{1}\)). Note that at equivalent latitudes, water on the eastern side of the ocean basins is colder than the water on the western side. This has to do with the pattern of surface currents, as described in section 9.1. Even though surface water can be quite warm, most of the water in the oceans is deeper, colder water, so that the average temperature of the entire ocean is about 4 o C, which is roughly the temperature inside your refrigerator.
A typical temperature profile for open ocean, mid-latitude water is shown in Figure \(\PageIndex{2}\). Water is warmest at the surface, as it is warmed by the sun, and the sun’s rays can only penetrate depths less than 1000 m (section 6.5). Since the surface water is warmer it is also less dense than the deep water (section 6.3), so it remains at the surface where it can be warmed even more. Temperature is fairly constant in the upper 100-200 m in what is called the mixed layer . The mixed layer results from surface winds, waves, and currents that mix the upper water and distribute the heat throughout this layer. Below the mixed layer there is a rapid decline in temperature over a fairly narrow increase in depth. This is called the thermocline . Below the thermocline the deep ocean temperature is fairly constant at about 2 o C, continuing down to the bottom. There is little temperature change in the deep ocean, as it is far removed from significant heat sources, making it one of the most thermally stable regions on earth. Temperature may fluctuate by less than half a degree per year in the deep ocean (Figure \(\PageIndex{3}\)).
Temperature profiles vary at different latitudes, as the surface water is warmer near the equator and colder at the poles. In low latitude tropical regions the sea surface is much warmer, leading to a highly pronounced thermocline (Figure \(\PageIndex{4}\)). Additionally, there is not much seasonal change in surface temperature in tropical regions, so there is little seasonal change in the profiles. In high latitude (polar) regions, there is little difference between the surface temperature and the deep water temperature, and temperature is fairly constant (and cold) at all depths. Polar waters therefore lack a strong thermocline, and as with tropical water, there is little seasonal change in temperatures. Mid-latitude temperate regions show greater seasonal fluctuations in surface temperature than the poles or the tropics; an 8-15 o C difference from summer to winter in temperate zones, compared to only ~2 o C in polar and tropical areas. In temperate regions, the surface water is much warmer in the summer and the thermocline is more pronounced compared to the winter months. But in the winter the thermocline is deeper at mid-latitudes than it is in the summer. This is because winter storms churn up the surface water more than occurs in the summer, creating a deeper mixed layer and thus a deeper thermocline (Figure \(\PageIndex{5}\)).
Due to the high heat capacity of water, daily fluctuations in ocean temperature are fairly insignificant.


7.1.8: Mitigating and Managing Risks
Learning Objectives
By the end of this section, you will be able to:
- Explain Enterprise Risk Management and how a company uses it
- Describe litigation and financial risks
- Describe common insurance needs
Risk management is key to operating any business in a profitable fashion. There are many risks facing an entrepreneur when starting and operating a new business venture. The trick is to eliminate risks that will hurt the venture, while taking on risks that will provide for long-term profitability. The risks facing the entrepreneur need to be initially identified as part of developing a business plan and revisited regularly in ongoing operations. Preparation for adverse events affecting a new business venture is necessary, but being too pessimistic or allowing fear of adverse events to stop an entrepreneur from taking any risk will keep a business venture from achieving its greatest potential and profit.
It is important that an entrepreneur develop an understanding of the risks of the business environment. The risks include liability risks stemming from contracts and torts, sometimes referred to as operating risks, regulatory compliance risks, financial risks, and strategic risks, including taxation. Understanding how the business structure is used to operate the business venture allows the entrepreneur to develop a plan to manage business growth and understand business risk.
Enterprise Risk Management
Profitable ventures develop a strong enterprise risk management program, which is an integrated, cross-disciplinary approach to monitoring risk. An organization needs to look at both long-term and short-term risks at all levels of the organization, and these risks need to be evaluated from all stakeholders’ perspectives and developed into an entity-wide program.
Enterprise risk management attempts to address the specific risks discussed in the preceding section by implementing a risk program that enables a business to identify and manage risk. Specifically, a business will go through a process that involves a multistage process of risk identification, risk assessment, and risk abatement. Examples of risks that businesses face include those from natural causes, economic causes, and human causes.
Natural causes of risk include disasters such as hurricanes and flooding, as well as earthquakes or other catastrophes that result in loss of life and property, as well as business interruption. For example, a business in New Orleans could be flooded by a hurricane. This results in damage to facilities and products, and threatens the lives of workers. In order to counter such causes, businesses need to plan ahead for business continuity, take out comprehensive insurance coverage, and have an evacuation/shut-down plan in place.
Economic causes of risk include global events leading to rising prices of raw materials, currency fluctuation, high interest rates, and, of course, competition from other companies in the same industry. An example of this would be unpredictable trade wars with China, leading to tariffs.
Human causes of risk refer to actions by employees, contractors, and those persons over which a company has control. These events can include torts stemming from negligence at work, labor strikes, shortages of qualified trained workers, and corporate mismanagement. An example of this type of risk would include embezzlement of money by an internal financial executive.
The use of a comprehensive approach allows a business entity to review and combine all risks into a functional perspective that allows the entrepreneur to evaluate risks and integrate new risks as different opportunities become more important to the business venture. Businesses sometimes use a risk matrix to assess or characterize the probability and impact of risk. The use of such a tool can help a business quantify risk and decide whether to undertake an activity based on its level of risk.
Risk appetite is important for a business venture to consider, both when creating its business structure and during ongoing operations. Table <IP_ADDRESS> shows an overview of the considerations a business venture should entertain in both its creation and operation.
| Risk Item | Consideration |
|---|---|
| Existing risk profile | Current level and distribution of risks across the business and across risk categories |
| Risk capacity | Amount of risk the business can support while pursuing its objectives |
| Risk tolerance | Amount of variation the business can tolerate while pursuing its objectives |
| Risk attitude | Management’s attitudes toward growth, risk, and return |
COSO’s Enterprise Risk Management, Understanding and Communicating Risk Appetite outlines these considerations for assessing a business’s appetite for risk.
This is the basic approach to evaluating a new venture’s appetite for risk. Determining and understanding the risks facing a new venture should start during the preparation of the business venture’s written business plan and should continue through the operations of the venture.
LINK TO LEARNING
The Committee of Sponsoring Organizations of the Treadway Commission, also known as COSO, deals with risk management. The mission statement of the COSO is “to provide thought leadership through the development of comprehensive frameworks and guidance on enterprise risk management, internal control and fraud deterrence designed to improve organizational performance and governance and to reduce the extent of fraud in organizations.”
Legal Risk and Protection
Business operations of any sort need to follow business regulations and laws. The failure to follow business regulations may lead to fines, lawsuits, or even criminal penalties. Legal risk stems primarily from a breach of contract and/or the commission of a tort. Common examples of this type of risk includes product liability lawsuits. These lawsuits are frequently very expensive class action lawsuits or regulatory investigations of dangerous products. There are many famous case examples including automobiles, asbestos, pharmaceutical drugs, breast implants, and airplanes.
Other lawsuits stem from contracts, including borrowing money from a bank. The business has an obligation to pay it back, or it breaches a covenant within a contract. Other common types of contracts are those used in selling services and products, leasing real estate, and other similar contractual obligations.
Due to liability risks, business owners and investors are always looking for ways to limit their personal liability. Incorporation is a standard risk protection strategy for this potential problem, as are the use of other types of limited liability structures such as LLCs. This is one of the main advantages of properly operated corporations and LLCs, which allow for limited personal liability of owners and investors. Partners in GPs and sole proprietors are personally liable for all of the debts of the business, even beyond their own investment in the business.
However, a particular challenge for small business entrepreneurs is that even when they form a corporation or LLC, many lenders, landlords, and other entities providing credit to a small business circumvent the limited liability protection by requiring owners and investors to personally guarantee the debts of the business operations. This means that the owner who personally guarantees the credit will have to pay back the obligation if the business cannot. An owner can obtain insurance or borrow money for such guarantees. LLCs and corporations do protect their owners, shareholders, and members from a number of different tort claims, such as personal injury lawsuits and claims made directly against the organization.
Financial Risk and Protection
An entrepreneur needs money to launch a business, whether that comes in the form of loans from family, their own savings, or investors. The founder will be expected to put their own money at risk, whether in the form of a loan to their own business or equity in their own business. If they do not have any “skin in the game,” then others will not be interested in loaning them money. This means that if the business fails, it will have repercussions for the owner, even if they operate as a corporation or LLC. This is the essence of financial risk : starting a new business with insufficient funds to sustain operations over an extended period of time.
Any new business owner needs to have a sound financial strategy as a part of the overall business plan. This should show income projections, the liquid assets that will be required to break even, and the expected return on investment for all investors in the first five-to-ten-year timeframe. Failure to accurately plan could mean that the entrepreneur risks business closure and bankruptcy, and investors get nothing.
Insurance Protection
Risk management and protection are enhanced with the purchase of different types of insurance , which involves spreading risk over a large number of people (policyholders). If a company is a corporation, it may need directors’ and officers’ liability insurance to indemnify the directors and officers if they get sued. Another insurance policy many companies get is called errors and omissions insurance, and this insurance coverage protects employees in negligence claims and cases if employee theft. Other types of insurance policies that most businesses carry include automobile insurance, health insurance, property insurance, and cyber/data breach insurance. Insurance coverage for a business venture needs to be specific to the business structure and its operations. Keep in mind that not all risks can be insured against—for example, a bad economy that leads to a loss of business or a bad decision by the owner to enter a market that does not work out.
Information Technology/Cybersecurity for Small Businesses
According to the SBA, the risk of hacking, ransomware, and customer privacy are equally as significant for most small businesses as for larger ones. The SBA has set guidelines related to cybersecurity for entrepreneurs. The SBA recommends the ten-step action plan shown in Table <IP_ADDRESS>.
| Step | Action |
|---|---|
| 1 | Protect against viruses, spyware, and other malicious code |
| 2 | Secure your networks |
| 3 | Establish security practices and policies to protect sensitive information |
| 4 | Educate employees about cyber threats and hold them accountable |
| 5 | Require employees to use strong passwords and change them often |
| 6 | Employ best practices on payment cards |
| 7 | Make backup copies of important business data and information |
| 8 | Control physical access to computers and network components |
| 9 | Create a mobile device action plan |
| 10 | Protect all pages on your public-facing websites and apps, not just the checkout and sign-up pages |
The Federal Communications Commission joins the SBA in the preceding recommendations. For more information, see the following website: https://www.fcc.gov/general/cybersec...small-business .

Managing Payment Data
If you operate a small business, are you prepared to deal with hackers who break into your website and steal credit card data from consumers who bought your products online? Small businesses running an e-commerce site must comply with the Payment Card Industry Data Security Standard ( https://www.pcisecuritystandards.org/ ). This is a regulation that could cause severe legal risk for entrepreneurs if your system is compromised, and credit card data are stolen. Consumers rightfully expect and demand a safe online experience when they visit your site. Have you paid an expert to evaluate your system and install the best security system? It may be costly, but perhaps not as expensive as the damages you could be ordered to pay by a court if credit card data are hacked.


15.1: The Genetic Code
Skills to Develop
- Explain the “central dogma” of protein synthesis
- Describe the genetic code and how the nucleotide sequence prescribes the amino acid and the protein sequence
The cellular process of transcription generates messenger RNA (mRNA), a mobile molecular copy of one or more genes with an alphabet of A, C, G, and uracil (U). Translation of the mRNA template converts nucleotide-based genetic information into a protein product. Protein sequences consist of 20 commonly occurring amino acids; therefore, it can be said that the protein alphabet consists of 20 letters (Figure \(\PageIndex{1}\)). Each amino acid is defined by a three-nucleotide sequence called the triplet codon. Different amino acids have different chemistries (such as acidic versus basic, or polar and nonpolar) and different structural constraints. Variation in amino acid sequence gives rise to enormous variation in protein structure and function.
The Central Dogma: DNA Encodes RNA; RNA Encodes Protein
The flow of genetic information in cells from DNA to mRNA to protein is described by the Central Dogma (Figure \(\PageIndex{2}\)), which states that genes specify the sequence of mRNAs, which in turn specify the sequence of proteins. The decoding of one molecule to another is performed by specific proteins and RNAs. Because the information stored in DNA is so central to cellular function, it makes intuitive sense that the cell would make mRNA copies of this information for protein synthesis, while keeping the DNA itself intact and protected. The copying of DNA to RNA is relatively straightforward, with one nucleotide being added to the mRNA strand for every nucleotide read in the DNA strand. The translation to protein is a bit more complex because three mRNA nucleotides correspond to one amino acid in the polypeptide sequence. However, the translation to protein is still systematic and colinear , such that nucleotides 1 to 3 correspond to amino acid 1, nucleotides 4 to 6 correspond to amino acid 2, and so on.
The Genetic Code Is Degenerate and Universal
Given the different numbers of “letters” in the mRNA and protein “alphabets,” scientists theorized that combinations of nucleotides corresponded to single amino acids. Nucleotide doublets would not be sufficient to specify every amino acid because there are only 16 possible two-nucleotide combinations (4 2 ). In contrast, there are 64 possible nucleotide triplets (4 3 ), which is far more than the number of amino acids. Scientists theorized that amino acids were encoded by nucleotide triplets and that the genetic code was degenerate . In other words, a given amino acid could be encoded by more than one nucleotide triplet. This was later confirmed experimentally; Francis Crick and Sydney Brenner used the chemical mutagen proflavin to insert one, two, or three nucleotides into the gene of a virus. When one or two nucleotides were inserted, protein synthesis was completely abolished. When three nucleotides were inserted, the protein was synthesized and functional. This demonstrated that three nucleotides specify each amino acid. These nucleotide triplets are called codons . The insertion of one or two nucleotides completely changed the triplet reading frame , thereby altering the message for every subsequent amino acid (Figure \(\PageIndex{4}\)). Though insertion of three nucleotides caused an extra amino acid to be inserted during translation, the integrity of the rest of the protein was maintained.
Scientists painstakingly solved the genetic code by translating synthetic mRNAs in vitro and sequencing the proteins they specified (Figure \(\PageIndex{3}\)).
In addition to instructing the addition of a specific amino acid to a polypeptide chain, three of the 64 codons terminate protein synthesis and release the polypeptide from the translation machinery. These triplets are called nonsense codons , or stop codons. Another codon, AUG, also has a special function. In addition to specifying the amino acid methionine, it also serves as the start codon to initiate translation. The reading frame for translation is set by the AUG start codon near the 5' end of the mRNA.
The genetic code is universal. With a few exceptions, virtually all species use the same genetic code for protein synthesis. Conservation of codons means that a purified mRNA encoding the globin protein in horses could be transferred to a tulip cell, and the tulip would synthesize horse globin. That there is only one genetic code is powerful evidence that all of life on Earth shares a common origin, especially considering that there are about 10 84 possible combinations of 20 amino acids and 64 triplet codons.
Link to Learning
Transcribe a gene and translate it to protein using complementary pairing and the genetic code at this site .
Degeneracy is believed to be a cellular mechanism to reduce the negative impact of random mutations. Codons that specify the same amino acid typically only differ by one nucleotide. In addition, amino acids with chemically similar side chains are encoded by similar codons. This nuance of the genetic code ensures that a single-nucleotide substitution mutation might either specify the same amino acid but have no effect or specify a similar amino acid, preventing the protein from being rendered completely nonfunctional.
Scientific Method Connection: Which Has More DNA: A Kiwi or a Strawberry?
Question: Would a kiwifruit and strawberry that are approximately the same size (Figure \(\PageIndex{5}\)) also have approximately the same amount of DNA?
Background: Genes are carried on chromosomes and are made of DNA. All mammals are diploid, meaning they have two copies of each chromosome. However, not all plants are diploid. The common strawberry is octoploid (8 n ) and the cultivated kiwi is hexaploid (6 n ). Research the total number of chromosomes in the cells of each of these fruits and think about how this might correspond to the amount of DNA in these fruits’ cell nuclei. Read about the technique of DNA isolation to understand how each step in the isolation protocol helps liberate and precipitate DNA.
Hypothesis: Hypothesize whether you would be able to detect a difference in DNA quantity from similarly sized strawberries and kiwis. Which fruit do you think would yield more DNA?
Test your hypothesis: Isolate the DNA from a strawberry and a kiwi that are similarly sized. Perform the experiment in at least triplicate for each fruit.
- Prepare a bottle of DNA extraction buffer from 900 mL water, 50 mL dish detergent, and two teaspoons of table salt. Mix by inversion (cap it and turn it upside down a few times).
- Grind a strawberry and a kiwifruit by hand in a plastic bag, or using a mortar and pestle, or with a metal bowl and the end of a blunt instrument. Grind for at least two minutes per fruit.
- Add 10 mL of the DNA extraction buffer to each fruit, and mix well for at least one minute.
- Remove cellular debris by filtering each fruit mixture through cheesecloth or porous cloth and into a funnel placed in a test tube or an appropriate container.
- Pour ice-cold ethanol or isopropanol (rubbing alcohol) into the test tube. You should observe white, precipitated DNA.
- Gather the DNA from each fruit by winding it around separate glass rods.
Record your observations: Because you are not quantitatively measuring DNA volume, you can record for each trial whether the two fruits produced the same or different amounts of DNA as observed by eye. If one or the other fruit produced noticeably more DNA, record this as well. Determine whether your observations are consistent with several pieces of each fruit.
Analyze your data: Did you notice an obvious difference in the amount of DNA produced by each fruit? Were your results reproducible?
Draw a conclusion: Given what you know about the number of chromosomes in each fruit, can you conclude that chromosome number necessarily correlates to DNA amount? Can you identify any drawbacks to this procedure? If you had access to a laboratory, how could you standardize your comparison and make it more quantitative?
Summary
The genetic code refers to the DNA alphabet (A, T, C, G), the RNA alphabet (A, U, C, G), and the polypeptide alphabet (20 amino acids). The Central Dogma describes the flow of genetic information in the cell from genes to mRNA to proteins. Genes are used to make mRNA by the process of transcription; mRNA is used to synthesize proteins by the process of translation. The genetic code is degenerate because 64 triplet codons in mRNA specify only 20 amino acids and three nonsense codons. Almost every species on the planet uses the same genetic code.
Glossary
- Central Dogma
- states that genes specify the sequence of mRNAs, which in turn specify the sequence of proteins
- codon
- three consecutive nucleotides in mRNA that specify the insertion of an amino acid or the release of a polypeptide chain during translation
- colinear
- in terms of RNA and protein, three “units” of RNA (nucleotides) specify one “unit” of protein (amino acid) in a consecutive fashion
- degeneracy
- (of the genetic code) describes that a given amino acid can be encoded by more than one nucleotide triplet; the code is degenerate, but not ambiguous
- nonsense codon
- one of the three mRNA codons that specifies termination of translation
- reading frame
- sequence of triplet codons in mRNA that specify a particular protein; a ribosome shift of one or two nucleotides in either direction completely abolishes synthesis of that protein


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Review of Key Points
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The Abrahamic religions include over 3.5 billion people around the world. Thus, they are an essential cultural consideration when examining the factors that influence personality.
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Judaism offers a simple set of guidelines for living one’s life, known as the Ten Commandments.
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Kabbalah is the mystical form of Judaism, which emphasizes blending one’s daily, worldly life with one’s spiritual life.
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Kabbalists encourage a way of incorporating the Ten Commandments into one’s life, in a manner reminiscent of Buddhist mindfulness. The meaningless alternative is to simply view the commandments as a static set of rules to be obeyed.
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Kabbalah, as an approach to the problems of daily life, compares favorably with cognitive psychotherapy.
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Past-life therapy relies on accepting the Kabbalistic belief in reincarnation, and using that knowledge to help people reconnect with their past lives.
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Christianity is the largest religion in the world, with over 2.2 billion followers.
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Jesus simplified the Ten Commandments to just two: love God, and love your neighbor as yourself.
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The early Christian mystics were desert hermits, who helped to establish both Christian mysticism and the monastic life.
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In Christian mysticism there have been many influential women saints, including some who challenged the patriarchal attitudes of men and one who became a great military leader (St. Joan of Arc).
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Fr. John Main, and his student Fr. Laurence Freeman, have actively worked to help bring simple Christian meditation techniques to people all around the world.
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Islam is the world’s second largest religion, with over 1.5 billion followers.
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Muslims follow a set of guidelines known as the Five Pillars of Islam.
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Sufism arose amongst those Muslims who did not wish to be drawn into the political and social battles that continue today between the sunni and shi’ah. Instead, Sufis seek to be drawn into Allah.
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Sufism has developed some most interesting practices, including sheikhs who became renowned poets and the whirling dervishes.
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In contrast to the conflicts between organized religions, and their supposed followers, there is extraordinary peace and both spiritual and intellectual interaction between mystics of many paths (Hindu, Taoist, Jewish, Christian, Muslim, etc.).
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Mystics recognize the difficulty that often arises in the form of confusion regarding their ways. Accordingly, they routinely emphasize the need for a teacher (guru, rabbi, sheikh, master, etc.) for those who wish to pursue a mystic path.
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Jihad is neither a holy war nor a requirement of Muslims. It is an urging to strive for faith, especially in the presence of those who are unfaithful. Christianity shares the same element, and it is known as ascesis.


13.17: The Distribution of Galaxies in Space
Learning Objectives
By the end of this section, you will be able to:
- Explain the cosmological principle and summarize the evidence that it applies on the largest scales of the known universe
- Describe the contents of the Local Group of galaxies
- Distinguish among groups, clusters, and superclusters of galaxies
- Describe the largest structures seen in the universe, including voids
In the preceding section, we emphasized the role of mergers in shaping the evolution of galaxies. In order to collide, galaxies must be fairly close together. To estimate how often collisions occur and how they affect galaxy evolution, astronomers need to know how galaxies are distributed in space and over cosmic time. Are most of them isolated from one another or do they congregate in groups? If they congregate, how large are the groups and how and when did they form? And how, in general, are galaxies and their groups arranged in the cosmos? Are there as many in one direction of the sky as in any other, for example? How did galaxies get to be arranged the way we find them today?
Edwin Hubble found answers to some of these questions only a few years after he first showed that the spiral nebulae were galaxies and not part of our Milky Way. As he examined galaxies all over the sky, Hubble made two discoveries that turned out to be crucial for studies of the evolution of the universe.
The Cosmological Principle
Hubble made his observations with what were then the world’s largest telescopes—the 100-inch and 60-inch reflectors on Mount Wilson. These telescopes have small fields of view: they can see only a small part of the heavens at a time. To photograph the entire sky with the 100-inch telescope, for example, would have taken longer than a human lifetime. So instead, Hubble sampled the sky in many regions, much as Herschel did with his star gauging (see The Architecture of the Galaxy). In the 1930s, Hubble photographed 1283 sample areas, and on each print, he carefully counted the numbers of galaxy images (Figure \(\PageIndex{1}\)).
The first discovery Hubble made from his survey was that the number of galaxies visible in each area of the sky is about the same. (Strictly speaking, this is true only if the light from distant galaxies is not absorbed by dust in our own Galaxy, but Hubble made corrections for this absorption.) He also found that the numbers of galaxies increase with faintness, as we would expect if the density of galaxies is about the same at all distances from us.
To understand what we mean, imagine you are taking snapshots in a crowded stadium during a sold-out concert. The people sitting near you look big, so only a few of them will fit into a photo. But if you focus on the people sitting in seats way on the other side of the stadium, they look so small that many more will fit into your picture. If all parts of the stadium have the same seat arrangements, then as you look farther and farther away, your photo will get more and more crowded with people. In the same way, as Hubble looked at fainter and fainter galaxies, he saw more and more of them.
Hubble’s findings are enormously important, for they indicate that the universe is both isotropic and homogeneous —it looks the same in all directions, and a large volume of space at any given redshift or distance is much like any other volume at that redshift. If that is so, it does not matter what section of the universe we observe (as long as it’s a sizable portion): any section will look the same as any other.
Hubble’s results—and many more that have followed in the nearly 100 years since then—imply not only that the universe is about the same everywhere (apart from changes with time) but also that aside from small-scale local differences, the part we can see around us is representative of the whole. The idea that the universe is the same everywhere is called the cosmological principle and is the starting assumption for nearly all theories that describe the entire universe (see The Big Bang).
Without the cosmological principle, we could make no progress at all in studying the universe. Suppose our own local neighborhood were unusual in some way. Then we could no more understand what the universe is like than if we were marooned on a warm south-sea island without outside communication and were trying to understand the geography of Earth. From our limited island vantage point, we could not know that some parts of the planet are covered with snow and ice, or that large continents exist with a much greater variety of terrain than that found on our island.
Hubble merely counted the numbers of galaxies in various directions without knowing how far away most of them were. With modern instruments, astronomers have measured the velocities and distances of hundreds of thousands of galaxies, and so built up a meaningful picture of the large-scale structure of the universe. In the rest of this section, we describe what we know about the distribution of galaxies, beginning with those that are nearby.
The Local Group
The region of the universe for which we have the most detailed information is, as you would expect, our own local neighborhood. It turns out that the Milky Way Galaxy is a member of a small group of galaxies called, not too imaginatively, the Local Group . It is spread over about 3 million light-years and contains more than 54 members. There are three large spiral galaxies (our own, the Andromeda galaxy, and M33), two intermediate ellipticals, and many dwarf ellipticals and irregular galaxies.
New members of the Local Group are still being discovered. We mentioned in The Milky Way Galaxy a dwarf galaxy only about 80,000 light-years from Earth and about 50,000 light-years from the center of the galaxy that was discovered in 1994 in the constellation of Sagittarius. (This dwarf is actually venturing too close to the much larger Milky Way and will eventually be consumed by it.)
Many of the recent discoveries have been made possible by the new generation of automated, sensitive, wide-field surveys, such as the Sloan Digital Sky Survey, that map the positions of millions of stars across most of the visible sky. By digging into the data with sophisticated computer programs, astronomers have turned up numerous tiny, faint dwarf galaxies that are all but invisible to the eye even in those deep telescopic images. These new findings may help solve a long-standing problem: the prevailing theories of how galaxies form predicted that there should be more dwarf galaxies around big galaxies like the Milky Way than had been observed—and only now do we have the tools to find these faint and tiny galaxies and begin to compare the numbers of them with theoretical predictions.
You can read more about the Sloan survey and its dramatic results. And check out this brief animation of a flight through the arrangement of the galaxies as revealed by the survey.
Several new dwarf galaxies have also been found near the Andromeda galaxy. Such dwarf galaxies are difficult to find because they typically contain relatively few stars, and it is hard to distinguish them from the foreground stars in our own Milky Way.
Figure \(\PageIndex{2}\) is a rough sketch showing where the brighter members of the Local Group are located. The average of the motions of all the galaxies in the Local Group indicates that its total mass is about \(4 × 10^{12}\) \(M_{\text{Sun}}\), and at least half of this mass is contained in the two giant spirals—the Andromeda galaxy and the Milky Way Galaxy. And bear in mind that a substantial amount of the mass in the Local Group is in the form of dark matter.
Neighboring Groups and Clusters
Small galaxy groups like ours are hard to notice at larger distances. However, there are much more substantial groups called galaxy clusters that are easier to spot even many millions of light-years away. Such clusters are described as poor or rich depending on how many galaxies they contain. Rich clusters have thousands or even tens of thousands of galaxies, although many of the galaxies are quite faint and hard to detect.
The nearest moderately rich galaxy cluster is called the Virgo Cluster, after the constellation in which it is seen. It is about 50 million light-years away and contains thousands of members, of which a few are shown in Figure \(\PageIndex{3}\). The giant elliptical (and very active) galaxy M87, which you came to know and love in the chapter on Active Galaxies, Quasars, and Supermassive Black Holes, belongs to the Virgo Cluster.
A good example of a cluster that is much larger than the Virgo complex is the Coma cluster, with a diameter of at least 10 million light-years (Figure \(\PageIndex{4}\)). Some 250 to 300 million light-years distant, this cluster is centered on two giant ellipticals whose luminosities equal about 400 billion Suns each. Thousands of galaxies have been observed in Coma, but the galaxies we see are almost certainly only part of what is really there. Dwarf galaxies are too faint to be seen at the distance of Coma, but we expect they are part of this cluster just as they are part of nearer ones. If so, then Coma likely contains tens of thousands of galaxies. The total mass of this cluster is about \(4 × 10^{15}\) \(M_{\text{Sun}}\) (enough mass to make 4 million billion stars like the Sun).
Let’s pause here for a moment of perspective. We are now discussing numbers by which even astronomers sometimes feel overwhelmed. The Coma cluster may have 10, 20, or 30 thousand galaxies, and each galaxy has billions and billions of stars. If you were traveling at the speed of light, it would still take you more than 10 million years (longer than the history of the human species) to cross this giant swarm of galaxies. And if you lived on a planet on the outskirts of one of these galaxies, many other members of the cluster would be close enough to be noteworthy sights in your nighttime sky.
Really rich clusters such as Coma usually have a high concentration of galaxies near the center. We can see giant elliptical galaxies in these central regions but few, if any, spiral galaxies. The spirals that do exist generally occur on the outskirts of clusters.
We might say that ellipticals are highly “social”: they are often found in groups and very much enjoy “hanging out” with other ellipticals in crowded situations. It is precisely in such crowds that collisions are most likely and, as we discussed earlier, we think that most large ellipticals are built through mergers of smaller galaxies.
Spirals, on the other hand, are more “shy”: they are more likely to be found in poor clusters or on the edges of rich clusters where collisions are less likely to disrupt the spiral arms or strip out the gas needed for continued star formation.
GRAVITATIONAL LENSING
As we saw in Black Holes and Curved Spacetime, spacetime is more strongly curved in regions where the gravitational field is strong. Light passing very near a concentration of matter appears to follow a curved path. In the case of starlight passing close to the Sun, we measure the position of the distant star to be slightly different from its true position.
Now let’s consider the case of light from a distant galaxy or quasar that passes near a concentration of matter such as a cluster of galaxies on its journey to our telescopes. According to general relativity, the light path may be bent in a variety of ways; as a result we can observe distorted and even multiple images (Figure \(\PageIndex{5}\)).
Gravitational lenses can produce not only double images, as shown in Figure \(\PageIndex{5}\), but also multiple images, arcs, or rings. The first gravitational lens discovered, in 1979, showed two images of the same distant object. Eventually, astronomers used the Hubble Space Telescope to capture remarkable images of the effects of gravitational lenses. One example is shown in Figure \(\PageIndex{6}\).
General relativity predicts that the light from a distant object may also be amplified by the lensing effect, thereby making otherwise invisible objects bright enough to detect. This is particularly useful for probing the earliest stages of galaxy formation, when the universe was young. Figure \(\PageIndex{7}\) shows an example of a very distant faint galaxy that we can study in detail only because its light path passes through a large concentration of massive galaxies and we now see a brighter image of it.
We should note that the visible mass in a galaxy is not the only possible gravitational lens. Dark matter can also reveal itself by producing this effect. Astronomers are using lensed images from all over the sky to learn more about where dark matter is located and how much of it exists.
Superclusters and Voids
After astronomers discovered clusters of galaxies, they naturally wondered whether there were still larger structures in the universe. Do clusters of galaxies gather together? To answer this question, we must be able to map large parts of the universe in three dimensions. We must know not only the position of each galaxy on the sky (that’s two dimensions) but also its distance from us (the third dimension).
This means we must be able to measure the redshift of each galaxy in our map. Taking a spectrum of each individual galaxy to do this is a much more time-consuming task than simply counting galaxies seen in different directions on the sky, as Hubble did. Today, astronomers have found ways to get the spectra of many galaxies in the same field of view (sometimes hundreds or even thousands at a time) to cut down the time it takes to finish their three-dimensional maps. Larger telescopes are also able to measure the redshifts—and therefore the distances—of much more distant galaxies and (again) to do so much more quickly than previously possible.
Another challenge astronomers faced in deciding how to go about constructing a map of the universe is similar to that confronted by the first team of explorers in a huge, uncharted territory on Earth. Since there is only one band of explorers and an enormous amount of land, they have to make choices about where to go first. One strategy might be to strike out in a straight line in order to get a sense of the terrain. They might, for example, cross some mostly empty prairies and then hit a dense forest. As they make their way through the forest, they learn how thick it is in the direction they are traveling, but not its width to their left or right. Then a river crosses their path; as they wade across, they can measure its width but learn nothing about its length. Still, as they go on in their straight line, they begin to get some sense of what the landscape is like and can make at least part of a map. Other explorers, striking out in other directions, will someday help fill in the remaining parts of that map.
Astronomers have traditionally had to make the same sort of choices. We cannot explore the universe in every direction to infinite “depth” or sensitivity: there are far too many galaxies and far too few telescopes to do the job. But we can pick a single direction or a small slice of the sky and start mapping the galaxies. Margaret Geller, the late John Huchra, and their students at the Harvard-Smithsonian Center for Astrophysics pioneered this technique, and several other groups have extended their work to cover larger volumes of space.
MARGARET GELLER: COSMIC SURVEYOR
Born in 1947, Margaret Geller is the daughter of a chemist who encouraged her interest in science and helped her visualize the three-dimensional structure of molecules as a child. (It was a skill that would later come in very handy for visualizing the three-dimensional structure of the universe.) She remembers being bored in elementary school, but she was encouraged to read on her own by her parents. Her recollections also include subtle messages from teachers that mathematics (her strong early interest) was not a field for girls, but she did not allow herself to be deterred.
Geller obtained a BA in physics from the University of California at Berkeley and became the second woman to receive a PhD in physics from Princeton. There, while working with James Peebles, one of the world’s leading cosmologists, she became interested in problems relating to the large-scale structure of the universe. In 1980, she accepted a research position at the Harvard-Smithsonian Center for Astrophysics, one of the nation’s most dynamic institutions for astronomy research. She saw that to make progress in understanding how galaxies and clusters are organized, a far more intensive series of surveys was required. Although it would not bear fruit for many years, Geller and her collaborators began the long, arduous task of mapping the galaxies (Figure \(\PageIndex{8}\)).
Her team was fortunate to be given access to a telescope that could be dedicated to their project, the 60-inch reflector on Mount Hopkins, near Tucson, Arizona, where they and their assistants took spectra to determine galaxy distances. To get a slice of the universe, they pointed their telescope at a predetermined position in the sky and then let the rotation of Earth bring new galaxies into their field of view. In this way, they measured the positions and redshifts of over 18,000 galaxies and made a wide range of interesting maps to display their data. Their surveys now include “slices” in both the Northern and Southern Hemispheres.
As news of her important work spread beyond the community of astronomers, Geller received a MacArthur Foundation Fellowship in 1990. These fellowships, popularly called “genius awards,” are designed to recognize truly creative work in a wide range of fields. Geller continues to have a strong interest in visualization and has (with filmmaker Boyd Estus) made several award-winning videos explaining her work to nonscientists (one is titled So Many Galaxies . . . So Little Time ). She has appeared on a variety of national news and documentary programs, including the MacNeil / Lehrer NewsHour , The Astronomers , and The Infinite Voyage . Energetic and outspoken, she has given talks on her work to many audiences around the country, and works hard to find ways to explain the significance of her pioneering surveys to the public.
“It’s exciting to discover something that nobody’s seen before. [To be] one of the first three people to ever see that slice of the universe [was] sort of being like Columbus. . . . Nobody expected such a striking pattern!” —Margaret Geller
Find out more about Geller and Huchra’s work (including interviews with Geller) in this 4-minute NOVA video. You can also learn more about their conclusions and additional research it led to.
The largest universe mapping project to date is the Sloan Digital Sky Survey (see the Making Connections feature box Astronomy and Technology: The Sloan Digital Sky Survey at the end of this section). A plot of the distribution of galaxies mapped by the Sloan survey is shown in Figure \(\PageIndex{8}\). To the surprise of astronomers, maps like the one in the figure showed that clusters of galaxies are not arranged uniformly throughout the universe, but are found in huge filamentary superclusters that look like great arcs of inkblots splattered across a page. The superclusters resemble an irregularly torn sheet of paper or a pancake in shape—they can extend for hundreds of millions of light-years in two dimensions, but are only 10 to 20 million light-years thick in the third dimension. Detailed study of some of these structures shows that their masses are a few times \(10^{16}\) \(M_{\text{Sun}}\), which is 10,000 times more massive than the Milky Way Galaxy.
Check out this animated visualization of large-scale structure from the Sloan survey.
Separating the filaments and sheets in a supercluster are voids , which look like huge empty bubbles walled in by the great arcs of galaxies. They have typical diameters of 150 million light-years, with the clusters of galaxies concentrated along their walls. The whole arrangement of filaments and voids reminds us of a sponge, the inside of a honeycomb, or a hunk of Swiss cheese with very large holes. If you take a good slice or cross-section through any of these, you will see something that looks roughly like Figure \(\PageIndex{8}\).
Before these voids were discovered, most astronomers would probably have predicted that the regions between giant clusters of galaxies were filled with many small groups of galaxies, or even with isolated individual galaxies. Careful searches within these voids have found few galaxies of any kind. Apparently, 90 percent of the galaxies occupy less than 10 percent of the volume of space.
Example \(\PageIndex{1}\): Galaxy distribution
To determine the distribution of galaxies in three-dimensional space, astronomers have to measure their positions and their redshifts. The larger the volume of space surveyed, the more likely the measurement is a fair sample of the universe as a whole. However, the work involved increases very rapidly as you increase the volume covered by the survey.
Let’s do a quick calculation to see why this is so.
Suppose that you have completed a survey of all the galaxies within 30 million light-years and you now want to survey to 60 million light-years. What volume of space is covered by your second survey? How much larger is this volume than the volume of your first survey? Remember that the volume of a sphere, V , is given by the formula
\[V = \dfrac{4}{3}\pi R^3 \nonumber\]
where \(R\) is the radius of the sphere.
- Answer
-
Since the volume of a sphere depends on \(R^3\) and the second survey reaches twice as far in distance, it will cover a volume that is \(2^3 = 8\) times larger. The total volume covered by the second survey will be
\[(4/3) \pi \times (60 \text{ million light-years})^3 = 9 \times 10^{23} \text{ light-years}^3. \nonumber\]
Exercise \(\PageIndex{1}\)
Suppose you now want to expand your survey to 90 million light-years. What volume of space is covered, and how much larger is it than the volume of the second survey?
- Answer
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The total volume covered is \[(4/3) \pi \times (90 \text{ million light-years})^3 = 3.05 \times 10^{24} \text{ light-years}^3. \nonumber\] The survey reaches 3 times as far in distance, so it will cover a volume that is \(3^3 = 27\) times larger.
Even larger, more sensitive telescopes and surveys are currently being designed and built to peer farther and farther out in space and back in time. The new 50-meter Large Millimeter Telescope in Mexico and the Atacama Large Millimeter Array in Chile can detect far-infrared and millimeter-wave radiation from massive starbursting galaxies at redshifts and thus distances more than 90% of the way back to the Big Bang. These cannot be observed with visible light because their star formation regions are wrapped in clouds of thick dust. And in 2021, the 6.5-meter-diameter James Webb Space Telescope is scheduled to launch. It will be the first new major visible light and near-infrared telescope in space since Hubble was launched more than 25 years earlier. One of the major goals of this telescope is to observe directly the light of the first galaxies and even the first stars to shine, less than half a billion years after the Big Bang.
At this point, if you have been thinking about our discussions of the expanding universe in Galaxies, you may be wondering what exactly in Figure \(\PageIndex{8}\) is expanding. We know that the galaxies and clusters of galaxies are held together by their gravity and do not expand as the universe does. However, the voids do grow larger and the filaments move farther apart as space stretches (see The Big Bang).
ASTRONOMY AND TECHNOLOGY: THE SLOAN DIGITAL SKY SURVEY
In Edwin Hubble’s day, spectra of galaxies had to be taken one at a time. The faint light of a distant galaxy gathered by a large telescope was put through a slit, and then a spectrometer (also called a spectrograph) was used to separate the colors and record the spectrum. This was a laborious process, ill suited to the demands of making large-scale maps that require the redshifts of many thousands of galaxies.
But new technology has come to the rescue of astronomers who seek three-dimensional maps of the universe of galaxies. One ambitious survey of the sky was produced using a special telescope, camera, and spectrograph atop the Sacramento Mountains of New Mexico. Called the Sloan Digital Sky Survey (SDSS), after the foundation that provided a large part of the funding, the program used a 2.5-meter telescope (about the same aperture as the Hubble) as a wide-angle astronomical camera. During a mapping program lasting more than ten years, astronomers used the SDSS’s 30 charge-coupled devices (CCDs)—sensitive electronic light detectors similar to those used in many digital cameras and cell phones—to take images of over 500 million objects and spectra of over 3 million, covering more than one-quarter of the celestial sphere. Like many large projects in modern science, the Sloan Survey involved scientists and engineers from many different institutions, ranging from universities to national laboratories.
Every clear night for more than a decade, astronomers used the instrument to make images recording the position and brightness of celestial objects in long strips of the sky. The information in each strip was digitally recorded and preserved for future generations. When the seeing (recall this term from Astronomical Instruments) was only adequate, the telescope was used for taking spectra of galaxies and quasars—but it did so for up to 640 objects at a time .
The key to the success of the project was a series of optical fibers , thin tubes of flexible glass that can transmit light from a source to the CCD that then records the spectrum. After taking images of a part of the sky and identifying which objects are galaxies, project scientists drilled an aluminum plate with holes for attaching fibers at the location of each galaxy. The telescope was then pointed at the right section of the sky, and the fibers led the light of each galaxy to the spectrometer for individual recording (Figure \(\PageIndex{9}\)).
About an hour was sufficient for each set of spectra, and the pre-drilled aluminum plates could be switched quickly. Thus, it was possible to take as many as 5000 spectra in one night (provided the weather was good enough).
The galaxy survey led to a more comprehensive map of the sky than has ever before been possible, allowing astronomers to test their ideas about large-scale structure and the evolution of galaxies against an impressive array of real data.
The information recorded by the Sloan Survey staggers the imagination. The data came in at 8 megabytes per second (this means 8 million individual numbers or characters every second). Over the course of the project, scientists recorded over 15 terabytes, or 15 thousand billion bytes, which they estimate is comparable to the information contained in the Library of Congress. Organizing and sorting this volume of data and extracting the useful scientific results it contains is a formidable challenge, even in our information age. Like many other fields, astronomy has now entered an era of “Big Data,” requiring supercomputers and advanced computer algorithms to sift through all those terabytes of data efficiently.
One very successful solution to the challenge of dealing with such large datasets is to turn to “citizen science,” or crowd-sourcing, an approach the SDSS helped pioneer. The human eye is very good at recognizing subtle differences among shapes, such as between two different spiral galaxies, while computers often fail at such tasks. When Sloan project astronomers wanted to catalog the shapes of some of the millions of galaxies in their new images, they launched the “Galaxy Zoo” project: volunteers around the world were given a short training course online, then were provided with a few dozen galaxy images to classify by eye. The project was wildly successful, resulting in over 40 million galaxy classifications by more than 100,000 volunteers and the discovery of whole new types of galaxies.
Learn more about how you can be part of the project of classifying galaxies in this citizen science effort. This program is part of a whole series of “citizen science” projects that enable people in all walks of life to be part of the research that professional astronomers (and scholars in a growing number of fields) need help with.
Key Concepts and Summary
Counts of galaxies in various directions establish that the universe on the large scale is homogeneous and isotropic (the same everywhere and the same in all directions, apart from evolutionary changes with time). The sameness of the universe everywhere is referred to as the cosmological principle. Galaxies are grouped together in clusters. The Milky Way Galaxy is a member of the Local Group, which contains at least 54 member galaxies. Rich clusters (such as Virgo and Coma) contain thousands or tens of thousands of galaxies. Galaxy clusters often group together with other clusters to form large-scale structures called superclusters, which can extend over distances of several hundred million light-years. Clusters and superclusters are found in filamentary structures that are huge but fill only a small fraction of space. Most of space consists of large voids between superclusters, with nearly all galaxies confined to less than 10% of the total volume.
Glossary
- cosmological principle
- the assumption that, on the large scale, the universe at any given time is the same everywhere—isotropic and homogeneous
- homogeneous
- having a consistent and even distribution of matter that is the same everywhere
- isotropic
- the same in all directions
- Local Group
- a small cluster of galaxies to which our Galaxy belongs
- supercluster
- a large region of space (more than 100 million light-years across) where groups and clusters of galaxies are more concentrated; a cluster of clusters of galaxies
- void
- a region between clusters and superclusters of galaxies that appears relatively empty of galaxies
Contributors and Attributions
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Andrew Fraknoi (Foothill College), David Morrison (NASA Ames Research Center), Sidney C. Wolff (National Optical Astronomy Observatory) with many contributing authors. Textbook content produced by OpenStax College is licensed under a Creative Commons Attribution License 4.0 license. Download for free at https://openstax.org/details/books/astronomy ).


7.7: Revising for Style
- Revise for style and wordiness
Revising for Style
During the revision process, you also want to be scan for appropriate word choice, sentence fluency, and voice.
Have you ever ordered a dish in a restaurant and been not happy with its taste, even though it contained most of your favorite ingredients? Just as a meal might lack the finishing touches needed to spice it up, so too might a paragraph contain all the basic components but still lack the stylistic finesse required to engage a reader. Sometimes writers have a tendency to reuse the same sentence pattern throughout their writing.
Like any repetitive task, reading text that contains too many sentences with the same length and structure can become monotonous and boring. Experienced writers mix it up by using an assortment of sentence patterns, rhythms, and lengths. Using a mixture of different sentence structures reduces repetition and adds emphasis to important points in the text.
In this extract from an election campaign, the writer uses short, simple sentences of a similar length and style. Notice that five of the seven sentences begin with the same word! This style that emphasizes repetition could be useful in the rhetorical context of a speech, but for a written text, the result is a choppy, unsophisticated paragraph that does not grab the audience’s attention.
During my time in office, I have achieved several goals. I have helped increase funding for local schools. I have reduced crime rates in the neighborhood. I have encouraged young people to get involved in their community. My competitor argues that she is the better choice in the upcoming election. I argue that it is ridiculous to fix something that isn’t broken. I promise to continue to serve this community if you reelect me this year.
https://h5p.cwr.olemiss.edu/h5p/embed/94
Not just right and wrong
Style is not a matter of right and wrong but of what is appropriate for each rhetorical context—that is, each particular communication task, setting, and audience.
When you first draft an essay, the sentences may sound informal or similar to the way that you speak. This is perfectly acceptable for the drafting process and for certain kinds of informal writing and rhetorical contexts. It is important, however, to be sure that the style of your writing matches the rhetorical situation.
Consider these differences between conversational, spoken language, and more formal, academic language:
| Spoken Language | Written Language |
| Shorter sentences | More complex sentences with varying structures |
| Vague words (e.g., stuff, some) | Precise, careful word choices |
|
Contractions, interjections, and slang
(e.g., can’t even, wow!, keep it 100) |
Non-colloquial, standard word choice |
Academic Style
Formal academic writing is concise and precise; the writer weeds out unnecessary words and chooses the exact word to convey meaning. Precise words—active verbs, concrete nouns, specific adjectives—help the reader visualize the sentence. In academic writing, we use adjectives sparingly and adverbs rarely, letting nouns and verbs do the work.
 Avoid slang. Find alternatives to lit, salty, lowkey, or any other contemporary terminology. Write about “men and women” rather than “girls and guys” unless you are trying to create a specific effect. A formal tone calls for formal language.
- Avoid clichés. Overused expressions such as outside the box, back in the day, feeling blue, and similar expressions are empty of meaning and may not appeal to your audience.
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Be judicious when you use phrases such as “in terms of,” “with a mind to,” “on the subject of,” “as to whether or not,” “more or less,” “as far as…is concerned,” and similar expressions. You can usually find a more straightforward way to state your point.
Wordy Revised As a world leader in the field of green technology, the company plans to focus its efforts in the area of geothermal energy. A report as to whether or not to use geysers as an energy source is in the process of preparation. As a world leader in green technology, the company plans to focus on geothermal energy. A report about using geysers as an energy source is in preparation.
Choosing words that are sensitive to your audience
As you revise for style, look closely at the language you have used in your drafts. Often, we write words that are fairly common but might be offensive to some readers or make them feel like they are excluded from being valuable members of your audience. Revision is a chance to think carefully about your language choices and to make sure you are considering all potential readers.
Below are some examples of language choices that can help you be more inclusive in your writing:
Gender terms
Use gender-neutral pronouns when appropriate. For example, don’t use the word “he” unless you are referring to just a male. Use terms like “he or she” when singular or “their” when plural. In fact, one easy way to make language more inclusive is to pluralize when possible. For example, a sentence such as, “Any student wishing to go on the trip must turn in his money to the teacher by Friday,” could easily be changed to, “Students wishing to go on the trip must turn in their money to the teacher by Friday.” Unless you were writing about an all-boys school, the second sentence is a much better choice.
Here are some other examples:
- police officer rather than policeman
- mail carrier rather than mailman
- humankind rather than mankind
Racial or ethnic terms
Use terms that are likely to not be offensive to readers. Despite common usage, some terms like “Indian” are not the preferred label for many members of that group. Additionally, it can be confusing because people from the country India can be called “Indian.” Use “Native American” or even “American Indian” instead.
Here are some other examples:
- Latino/a or Latinx (or the appropriate specific ethnicity), rather than Mexican
- African-American or Black rather than colored or other terms
- Inuit or Native Alaskan rather than Eskimo
Writing about disabilities
Terms referring to disabilities are often insensitive and sometimes even inaccurate. For example, the term “blind” has negative connotations. Think about how we also use it in negative ways: “Jill is blind to the fact that her old friends don’t want to hang out with her anymore.” Further, some people may be called blind when they actually have partial vision. The term “visually impaired” is a better choice for multiple reasons, even when someone has complete loss of sight.
 Authored by : Guy Krueger. Provided by : University of Mississippi. License : CC BY: Attribution
- Revising for Style: Wordiness. Authored by : Alison Hitch. Provided by : University of Mississippi. License : CC BY: Attribution
- Style, Oral versus Written Language. Provided by : Lumen Learning/SUNY OER Services. Located at : https://courses.lumenlearning.com/suny-fmcc-standupspeakout1/chapter/oral-versus-written-language/ . Project : Speak Up, Speak Out. License : CC BY-SA: Attribution-ShareAlike
- Image of scrabble tiles. Authored by : Wokandapix. Provided by : Pixabay. Located at : pixabay.com/photos/keywords-letters-scrabble-word-2041816/. License : Other . License Terms : pixabay.com/service/terms/#license
- Academic Voice. Authored by : Excelsior OWL. Located at : https://owl.excelsior.edu/writing-process/finding-your-voice/finding-your-voice-tips-on-academic-voice/ . License : Public Domain: No Known Copyright
- Image of senior couple. Authored by : pasja1000. Located at : pixabay.com/photos/senior-elderly-people-couple-3336451/. License : Other . License Terms : pixabay.com/service/terms/#license


20.12: Checklist for Wound Cleansing, Irrigation, and Packing
Cleansing is an important step when changing dressings in wounds healing by secondary intention to remove surface debris and to provide optimal visualization for the wound assessment. See Figure \(\PageIndex{1}\) [1] for removal of dressing and wound assessment.
Follow agency policy and provider orders regarding cleansing solution and method. Many wounds can be cleansed with normal saline. See Figure \(\PageIndex{2}\) [2] for an example of wound irrigation.
Cleansing solution should be applied with sufficient pressure to cleanse the wound without damaging tissue or driving bacteria into the wound. [3] Following cleansing, the wound may be packed to allow for granulation of new tissue. See Figure \(\PageIndex{3}\) [4] for an example of wound packing.
Checklist for Wound Cleansing, Irrigation, and Packing
Use the checklist below to review the steps for completion of “Wound Cleansing, Irrigation, and Packing.”
Steps
Disclaimer: Always review and follow agency policy regarding this specific skill.
- Gather supplies: syringe, cannula with needleless adaptor, irrigation fluid, basin, waterproof pad, dressing tray with sterile forceps, scissors, skin barrier/protectant, cotton tip applicators, measuring guide, outer sterile dressing, and packing gauze or packing as per physician’s orders.
-
Perform safety steps:
- Perform hand hygiene.
- Check the room for transmission-based precautions.
- Introduce yourself, your role, the purpose of your visit, and an estimate of the time it will take.
- Confirm patient ID using two patient identifiers (e.g., name and date of birth).
- Explain the process to the patient and ask if they have any questions.
- Be organized and systematic.
- Use appropriate listening and questioning skills.
- Listen and attend to patient cues.
- Ensure the patient’s privacy and dignity.
- Assess ABCs.
- Confirm the provider order and verify appropriateness of order according to wound assessment.
- Prepare the environment, position the patient, adjust the height of the bed, and turn on the lights. Ensure proper lighting to allow for good visibility to assess the wound. Ensure proper body mechanics for yourself and create a comfortable position for the patient. Position the patient so the wound is vertical to the collection basin, if possible, to allow the solution to flow off the patient.
- Place a waterproof pad under the patient to protect the patient’s clothing and bedding from irrigation fluid.
- Perform hand hygiene and apply clean gloves.
-
Remove outer dressing:
- Using sterile forceps, remove the inner dressing (packing) from the wound.
- If the packing sticks, gently soak the packing with normal saline or sterile water and gently lift off the packing. Removing packing that adheres to the wound bed without soaking can cause trauma to the wound bed tissue. If packing material cannot be removed, contact the provider. If packing adheres to the wound, reassess the amount of wound exudate and consider a different packing material. All packing must be removed with each dressing change.
- Confirm the quantity and type of packing are the same as recorded on previous dressing change.
-
Assess the wound:
- Note the location and type of wound.
- Measure the wound’s length, width, and depth.
- If undermining or tunneling are present, note the location and measure the depth.
- Determine if the level of tissue damage indicates wound healing or worsening.
- Assess appearance of wound bed, noting color.
- Note presence of odor after cleansing.
- Assess appearance of periwound skin.
- Wound assessment helps identify if the wound care is effective. Always compare the current wound assessment with the previous assessment to determine if the wound is healing, delayed, worsening, or showing signs of infection.
- Apply nonsterile gloves, gown, and goggles or face shield according to agency policy.
- If irrigation is indicated, fill a 35-mL syringe with sterile saline and attach a needleless cannula to the end of the syringe.
-
Hold the syringe about 1 inch above the wound and flush gently with continuous pressure until returned fluid is clear:
- Irrigation should be drained into the basin because it is a medium for bacterial growth and subsequent infection.
- Irrigation should not increase patient discomfort.
- Dry wound edges with sterile gauze using sterile forceps to prevent maceration of surrounding tissue from excess moisture.
- Remove goggles or face shield and gloves.
- Perform hand hygiene and apply sterile gloves (if not using sterile forceps) or nonsterile gloves if using sterile forceps.
- Apply a skin barrier/protectant on the periwound skin as needed to prevent saturated packing materials and/or wound exudate from macerating or irritating the periwound skin.
-
While maintaining sterility, moisten the gauze with sterile normal saline and wring it out so it is damp but not wet:
- The wound must be moist, not wet, for optimal healing. Gauze packing that is too wet can cause tissue maceration and reduces the absorbency of the gauze.
- Normal saline gauze packing needs to be changed at least once daily.
- Ensure the wound is not overpacked or underpacked as either may diminish the healing process.
-
Open the gauze and gently pack it into the wound using sterile forceps or the tip of a sterile, cotton-tipped swab:
- Continue until all wound surfaces are in contact with gauze.
- Do not pack too tightly.
- Do not overlap wound edges with wet packing.
-
Apply an appropriate outer dry dressing, depending on the frequency of the dressing changes and the amount of exudate from the wound:
- The dressing on the wound must remain dry on the outside to avoid cross-contamination of the wound. If it becomes saturated before the next dressing change, it must be replaced.
- Discard the supplies.
- Remove gloves and perform hand hygiene.
- Assist the patient to a comfortable position, ask if they have any questions, and thank them for their time.
-
Ensure safety measures when leaving the room:
- CALL LIGHT: Within reach
- BED: Low and locked (in lowest position and brakes on)
- SIDE RAILS: Secured
- TABLE: Within reach
- ROOM: Risk-free for falls (scan room and clear any obstacles)
- Document procedure, wound assessment, irrigation solution, and patient response to the irrigation and dressing change. Report any concerns according to agency policy.
- “DSC_1724.jpg,” "SC_1727.jpg,” and “DSC_1730.jpg” by British Columbia Institute of Technology are licensed under CC BY 4.0. Access for free at https://ecampusontario.pressbooks.pub/clinicalskills/chapter/4-5-complex-dressing-change/ ↵
- “DSC_1732.jpg” by British Columbia Institute of Technology is licensed under CC BY 4.0. Access for free at https://ecampusontario.pressbooks.pub/clinicalskills/chapter/4-5-complex-dressing-change/ ↵
- National Pressure Ulcer Advisory Panel, European Pressure Ulcer Advisory Panel and Pan Pacific Pressure Injury Alliance. (2014). Prevention and treatment of pressure ulcers: Quick reference guide. Emily Haesler (Ed.). https://www.epuap.org/wp-content/uploads/2010/10/Quick-Reference-Guide-DIGITAL-NPUAP-EPUAP-PPPIA-16Oct2014.pdf ↵
- “DSC_1742.jpg” by British Columbia Institute of Technology is licensed under CC BY 4.0. Access for free at https://ecampusontario.pressbooks.pub/clinicalskills/chapter/4-5-complex-dressing-change/ ↵