19.14.1: Review Questions
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Review Questions
1 .
What type of dystocia occurs when the fetal head is unable to navigate through the pelvis?
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uterine dystocia
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fetal dystocia
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pelvic dystocia
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contraction dystocia
2 .
What type of dystocia should the nurse prepare for if she palpates prominent ischial spines during the vaginal exam?
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pelvic dystocia
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fetal dystocia
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contraction dystocia
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uterine dystocia
3 .
What pregnant person is at high risk for labor dystocia?
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38-week gestation
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41-year-old
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prenatal anemia
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no prenatal care
4 .
The nurse is caring for a pregnant person who was in a motor vehicle accident when she was younger and broke a bone in her pelvis. For what complication should the nurse be prepared?
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fetal dystocia
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pelvic dystocia
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uterine dystocia
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age dystocia
5 .
What Bishop score describes the most favorable cervix?
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2
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4
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6
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8
6 .
What is a possible complication of uterine tachysystole?
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Category I fetal heart rate tracing
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placenta previa
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fetal hypoxia
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prolapsed cord
7 .
What can amniotomy cause?
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six-hour decrease of labor
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chorioamnionitis
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elevated blood pressure
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second stage labor dystocia
8 .
What medication is used for cervical ripening?
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amniotomy
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Hemabate
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misoprostol
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progesterone
9 .
How often is oxytocin usually increased for induction or augmentation of labor?
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every 10 minutes
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every 30 minutes
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every 60 minutes
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every 90 minutes
10 .
What is a potential complication for the neonate due to precipitous labor?
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respiratory distress
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low birth weight
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prelabor rupture of membranes
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placenta previa
11 .
What nursing intervention is performed during labor for a person with preeclampsia?
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Assess deep tendon reflexes for hyperreflexia.
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Provide frequent IV fluid boluses.
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Educate the laboring person that preeclampsia is only a concern for pregnancy, not labor.
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Discourage pain medication in order to assess for headache.
12 .
What is a condition in which there is an excessive amount of amniotic fluid surrounding the fetus?
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amniotic fluid embolism
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gestational diabetes
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oligohydramnios
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polyhydramnios
13 .
What is a possible complication of oligohydramnios?
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fetal macrosomia
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preterm labor
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placenta previa
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fetal growth restriction
14 .
What medication should the nurse anticipate administering when caring for a person with preeclampsia in labor?
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ampicillin
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magnesium sulfate
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nalbuphine hydrocholoride (Nubain)
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sodium bicarbonate
15 .
What is a potential sign of intrauterine fetal demise?
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increased fetal heart rate
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vaginal bleeding
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decreased or absent fetal movement
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macrosomia
16 .
What is a potential complication when the fetus is footling breech?
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prolapsed cord
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oligohydramnios
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low biophysical profile score
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meconium-stained fluid
17 .
Gestational diabetes increases what complication of labor?
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breech
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macrosomia
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postterm birth
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precipitous birth
18 .
Multiple gestation can lead to what labor complication?
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tachysystole
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postterm birth
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uterine dystocia
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early declarations
19 .
With what is malnutrition during pregnancy associated?
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fetal growth restriction
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fetal macrosomia
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group B strep
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precipitous birth
20 .
What newborn complication does type 1 diabetes mellitus cause?
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hyperglycemia
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umbilical hernia
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hypoglycemia
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cyanosis
21 .
With what has maternal hypertension been associated?
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anorexia
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low birth weight
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macrosomia
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symphysis pubis dysfunction
22 .
What is one potential fetal complication of using obstetric forceps?
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flexion of the head
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abdominal complications
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skull fracture
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femur fracture
23 .
What is one potential fetal complication of using the vacuum extractor?
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cephalohematoma
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face presentation
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fetal growth restriction
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scalp fracture
24 .
What is a common reason for cesarean birth?
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cephalic presentation
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laboring person’s BMI of 23
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labor dystocia
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lack of adequate pain control
25 .
What condition is related to an increased risk for fetal demise?
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diabetes
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migraine headache
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spina bifida
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thyroid disorder
26 .
Why is multiple gestation is a risk factor for cesarean delivery?
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cord prolapse
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increased pain in labor
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inability to push
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twins in cephalic-cephalic presentation
27 .
What is the condition where the umbilical cord vessels cross the cervix?
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placenta previa
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placenta cervix
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velamentous insertion
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vasa previa
28 .
What is the condition in which the umbilical cord vessels branch prior to insertion into the placenta?
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placenta previa
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placenta cervix
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velamentous insertion
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vasa previa
29 .
What is a sign of fetal distress?
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prolonged moderate variability
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accelerations
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repetitive late decelerations
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variable decelerations
30 .
Shoulder dystocia is difficult to predict. What are thought to be predictors for shoulder dystocia? Select all that apply.
- estimated birth weight of 4,000 g
- gestational diabetes
- previous shoulder dystocia
- oligohydramnios
- hypertension
- preterm delivery
31 .
How soon should delivery of the fetus occur when a Category III FHR tracing is diagnosed?
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15 minutes
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30 minutes
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45 minutes
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60 minutes
32 .
What is a complication of uterine rupture?
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DIC
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nuchal cord
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polyhydramnios
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oligohydramnios
33 .
What is the nursing intervention for prolapsed cord?
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Turn the person to the side.
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Give the person oxygen.
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Lift the presenting part off the cord.
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Increase the oxytocin.
34 .
At what point is the second stage considered prolonged for a nulliparous laboring person?
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1 hour
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2 hours
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3 hours
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4 hours
35 .
What is a potential risk associated with prolonged second stage labor?
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decreased risk of instrumental delivery
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decreased risk of cesarean birth
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increased risk of fetal distress
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increased risk of rapid delivery
36 .
What intervention may be used to manage failure to descend during labor?
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administering pain medication
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allowing the patient to rest
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continuing to push for an extended period of time
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using forceps or a vacuum to assist delivery
37 .
The placenta is diagnosed as retained when it is not delivered in what timeframe after the birth of the infant?
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10 minutes
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30 minutes
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1 hour
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2 hours
38 .
In a spontaneous abortion, if bleeding from the retained products of conception cannot be stopped, what is the next course of action?
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surgery for a dilation and curettage
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surgery for a hysterectomy
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administration of magnesium sulfate
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administration of calcium gluconate
39 .
What is the most common cause of placenta accreta?
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malnutrition
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smoking
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previous cesarean birth
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obesity
40 .
How much blood loss must occur to define the loss as a postpartum hemorrhage?
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250 mL
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500 mL
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750 mL
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1,000 mL
41 .
What medication is administered to treat uterine atony?
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ampicillin
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nitroglycerine
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magnesium sulfate
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methylergonovine
42 .
What complication makes uterine inversion an emergency?
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shock
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pain
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retained placenta
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hypertension
43 .
Decreased capillary refill, delay in milk production, and diminished peripheral pulses are signs of what complication?
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alteration in perfusion
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alteration in liver function
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alteration in kidney function
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alteration in uterine function
44 .
The nurse is caring for a postpartum person after a hemorrhage. How does the nurse monitor for decreased perfusion?
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Monitor lochia.
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Measure blood loss.
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Check temperature.
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Monitor 24-hour urine output.
45 .
What condition do restlessness, cyanosis, nasal flaring, orthopnea, and use of accessory muscles indicate?
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liver failure
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alteration in oxygenation
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preeclampsia
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gestational diabetes
46 .
The nurse will monitor for aspiration, thought processes, and improved mobility after which complication?
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neurologic dysfunction
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kidney failure
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gestational diabetes
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postpartum hemorrhage
47 .
What complications can cocaine and methamphetamine use in pregnancy cause?
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seizures
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hypotonic contractions
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prolonged second stage labor
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prolonged first stage labor


4: Sedimentary Structures
Sedimentary structures are important because they tell us about processes that were operating during the deposition of that sediment. Things like flow velocity, depth, and direction can be determined from some sorts of structures. From there, we can start to make some educated guesses about what sorts of depositional environments these processes were taking place in. But, the first step is having the vocabulary to describe what you are seeing.
- Identify common sedimentary structures
- Interpret appropriate sedimentary structures to determine paleoflow direction
- Interpret and describe the processes responsible for and recorded by sedimentary structures
- Use appropriate sedimentary structures to determine way up and top/bottom of beds
Chapter thumbnail shows eolian sand dunes in Death Valley National Park ( Michael C. Rygel via Wikimedia Commons ; CC BY-SA 4.0 ).


3.6: Teratogens
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A look at some teratogens
One of the most commonly used teratogens is alcohol and because half of all pregnancies in the United States are unplanned, it is recommended that women of child-bearing age take great caution against drinking alcohol when not using birth control or when pregnant (Surgeon General’s Advisory on Alcohol Use During Pregnancy, 2005). Alcohol consumption, particularly during the second month of prenatal development but at any point during pregnancy may lead to neurocognitive and behavioral difficulties that can last a lifetime. Binge drinking (5 or more on a single occasion) or 7 or more drinks during a single week place a child at risk. In extreme cases, alcohol consumption can lead to fetal death but more frequently it can result in fetal alcohol spectrum disorders (FASD). FASD is the terminology that is now used when looking at the effects of exposure and replaces the term fetal alcohol syndrome (FAS), although you may see the two terms used interchangeably. FASD is preferred because it recognizes that symptoms occur on a spectrum and that all individuals are not equally impacted. Children with FASD share certain physical features such as flattened noses, small eye holes, and small heads, intellectual developmental delay, and behavioral problems. Those with FASD are more at risk for lifelong problems such as criminal behavior, psychiatric problems, and unemployment (CDC, 2006). The terms alcohol-related neurological disorder (ARND) and alcohol-related birth defects (ARBD) have replaced the term Fetal Alcohol Effects to refer to those with less extreme symptoms of FASD. ARBD include kidney, bone and heart problems.
Tobacco is the second most widely used teratogen and the number of adolescent females who smoke is increasing. In fact, among adolescents, females are just as likely to smoke as are males. Tobacco use during pregnancy has been associated with low birth weight, placenta previa, preterm delivery, fetal growth restriction and sudden infant death syndrome (Center for Disease Control, 2004).
Illicit drugs as well as prescribed medications can have serious teratogenic effects. It is difficult to completely determine the effects of a particular illicit drug on a developing child because most mothers, who use, use more than one substance. However, several problems seem clear. The use of cocaine is connected with low birth weight, stillbirths and spontaneous abortion. Heavy marijuana use is associated with brain damage and ADHD and mothers addicted to heroin often pass that addiction to their child. And many medications do not include adequate information on risks posed if taken during pregnancy (Center for Disease Control, 2004).
Pollutants
Some environmental pollutants of major concern include lead poisoning, which is connected with low birth weight and slowed neurological development. Children who live in older housing in which lead based paints have been used have been known to eat peeling paint chips thus being exposed to lead. The chemicals in certain herbicides are also potentially damaging. Radiation is another environmental hazard.  There is also an increased risk of miscarriage and stillbirth. Mercury leads to physical deformities and intellectual development delay (Dietrich, 1999).
HIV
One of the most potentially devastating teratogens is HIV. It is estimated that between 630,000 to 820,000 children were newly infected with HIV worldwide in 2005. Most of this infection is from mother-to-child through the placenta or birth canal (Newell, 2005). Fortunately, there are measures that can be taken to lower the chance the child will contract the disease (such as the use of antiretroviral drugs from 14 weeks after conception until birth, avoiding breastfeeding, and delivering the child by c-section). Unfortunately, some women do not know they are HIV positive during pregnancy and others cannot afford the costly drugs used for treating AIDS. The transmission rate of HIV from mother to child has been reduced in the United States to between 100-200 infants annually.
Maternal Diseases
German measles (or rubella) have been associated with a number of maladies. If the mother contracts the disease during the first three months of pregnancy, damage can occur in the eyes, ears, heart or brain of the unborn child. Deafness is almost certain if the mother has German measles before the 11th week of prenatal development and can also cause brain damage. Gonorrhea, syphilis, and Chlamydia are sexually transmitted infections that can be passed to the fetus by an infected mother; mothers should be tested as early as possible to minimize the risk of spreading these infections (Center for Disease Control, 2006).
Pregnancy
Complications of Pregnancy
Minor complications: There are a number of common side effects of pregnancy. Not everyone experiences all of these nor to the same degree. And although they are considered “minor” this is not to say that these problems are potentially very uncomfortable. These side effects include nausea (particularly during the first 3-4 months of pregnancy as a result of higher levels of estrogen in the system), heartburn, gas, hemorrhoids, backache, leg cramps, insomnia, constipation, shortness of breath or varicose veins (as a result of carrying a heavy load on the abdomen). What is the cure? Delivery!
Major Complications: The following are some serious complications of pregnancy which can pose health risks to mother and child and that often require hospitalization. Ectopic pregnancy occurs when the zygote becomes attached to the fallopian tube before reaching the uterus. About 1 in 50 pregnancies in the United States are tubal pregnancies and this number has been increasing because of the higher rates of pelvic inflammatory disease and Chlamydia (Carroll, 2007). Abdominal pain, vaginal bleeding, nausea and fainting are symptoms of ectopic pregnancy. Toxemia or blood poisoning due to kidney malfunction is experienced by 6 to 7 percent of women during their last months of pregnancy. If untreated toxemia can lead to preeclampsia or swelling and hypertension or progress to eclampsia which is can involve coma or death.
 Rates are highest in Subsaharan Africa and South Asia although there has been a substantial decrease in these rates. The campaign to make childbirth safe for everyone has led to the development of clinics accessible to those living in more isolated areas and training more midwives to assist in childbirth.
Potential Problems
Low Birth weight
We have been discussing a number of teratogens associated with low birth weight such as cocaine, tobacco, etc. A child is considered low birth weight if he or she weighs less than 5.8 pounds (2500 grams). About 8.2 percent of babies born in the United States are of low birth weight (Center for Disease Control, 2010). A low birth weight baby has difficulty maintaining adequate body temperature because it lacks the fat that would otherwise provide insulation. Such a baby is also at more risk for infection. And 67 percent of these babies are also preterm which can make them more at risk for respiratory infection. Very low birth weight babies (2 pounds or less) have an increased risk of developing cerebral palsy. Many causes of low birth weight are preventable with proper prenatal care, however.
Premature Birth
A child might also have a low birth weight if it is born at less than 37 weeks gestation (which qualifies it as a preterm baby). Early birth can be triggered by anything that disrupts the mother’s system. For instance, vaginal infections or gum disease can actually lead to premature birth because such infection causes the mother to release anti-inflammatory chemicals which, in turn, can trigger contractions. Smoking and the use of other teratogens can lead to preterm birth.
Anoxia
Anoxia is a temporary lack of oxygen to the brain. Difficulty during delivery may lead to anoxia which can result in brain damage or in severe cases, death. Babies who suffer both low birth weight and anoxia are more likely to suffer learning disabilities later in life as well.


Describe human development and its three domains: physical, cognitive, and psychosocial development
Explain key human development issues about the nature of change: continuous/discontinuous, one course/multiple courses, and nature/nurture
Domains in Human Development
Human development refers to the physical, cognitive, and psychosocial development of humans throughout the lifespan. What types of development are involved in each of these three domains, or areas, of life? Physical development involves growth and changes in the body and brain, the senses, motor skills, and health and wellness. Cognitive development involves learning, attention, memory, language, thinking, reasoning, and creativity. Psychosocial development involves emotions, personality, and social relationships.
Physical Domain
Many of us are familiar with the height and weight charts that pediatricians consult to estimate if babies, children, and teens are growing within normative ranges of physical development. We may also be aware of changes in children’s fine and gross motor skills, as well as their increasing coordination, particularly in terms of playing sports. But we may not realize that physical development also involves brain development, which not only enables childhood motor coordination but also greater coordination between emotions and planning in adulthood, as our brains are not done developing in infancy or childhood. Physical development also includes puberty, sexual health, fertility, menopause, changes in our senses, and primary versus secondary aging. Healthy habits with nutrition and exercise are also important at every age and stage across the lifespan.
Cognitive Domain
If we watch and listen to infants and toddlers, we can’t help but wonder how they learn so much so fast, particularly when it comes to language development. Then as we compare young children to those in middle childhood, there appear to be huge differences in their ability to think logically about the concrete world around them. Cognitive development includes mental processes, thinking, learning, and understanding, and it doesn’t stop in childhood. Adolescents develop the ability to think logically about the abstract world (and may like to debate matters with adults as they exercise their new cognitive skills!). Moral reasoning develops further, as does practical intelligence—wisdom may develop with experience over time. Memory abilities and different forms of intelligence tend to change with age. Brain development and the brain’s ability to change and compensate for losses is significant to cognitive functions across the lifespan, too.
Psychosocial Domain
Development in this domain involves what’s going on both psychologically and socially. Early on, the focus is on infants and caregivers, as temperament and attachment are significant. As the social world expands and the child grows psychologically, different types of play and interactions with other children and teachers become important. Psychosocial development involves emotions, personality, self-esteem, and relationships. Peers become more important for adolescents, who are exploring new roles and forming their own identities. Dating, romance, cohabitation, marriage, having children, and finding work or a career are all parts of the transition into adulthood. Psychosocial development continues across adulthood with similar (and some different) developmental issues of family, friends, parenting, romance, divorce, remarriage, blended families, caregiving for elders, becoming grandparents and great grandparents, retirement, new careers, coping with losses, and death and dying.
As you may have already noticed, physical, cognitive, and psychosocial development are often interrelated, as with the example of brain development. We will be examining human development in these three domains in detail throughout the modules in this course, as we learn about infancy/toddlerhood, early childhood, middle childhood, adolescence, young adulthood, middle adulthood, and late adulthood development, as well as death and dying.
Who Studies Human Development and Why?
Many academic disciplines contribute to the study of development and this type of course is offered in some schools as psychology (particularly as developmental psychology); in other schools, it is taught under sociology, human development, or family studies. This multidisciplinary course is made up of contributions from researchers in the areas of health care, anthropology, nutrition, child development, biology, gerontology, psychology, and sociology, among others. Consequently, the stories provided are rich and well-rounded and the theories and findings can be part of a collaborative effort to understand human lives.
The main goals of those involved in studying human development are to describe and explain changes. Throughout this course, we will describe observations during development, then examine how theories provide explanations for why these changes occur. For example, you may observe two-year-old children to be particularly temperamental, and researchers offer theories to explain why that is. We’ll learn a lot more about theories, especially developmental theories, in the next module.
There are many different theoretical approaches regarding human development. As we evaluate them in this course, recall that human development focuses on how people change, and the approaches address the nature of change in different ways:
Is the change smooth or uneven (continuous versus discontinuous)?
Is this pattern of change the same for everyone, or are there different patterns of change (one course of development versus many courses)?
How do genetics and environment interact to influence development (nature versus nurture)?
Is Development Continuous or Discontinuous?
Continuous development
views development as a cumulative process, gradually improving on existing skills (Figure 2). With this type of development, there is a gradual change. Consider, for example, a child’s physical growth: adding inches to their height year by year. In contrast, theorists who view development as
discontinuous
believe that development takes place in unique stages and that it occurs at specific times or ages. With this type of development, the change is more sudden, such as an infant’s ability to demonstrate awareness of object permanence (which is a cognitive skill that develops toward the end of infancy, according to Piaget’s cognitive theory—more on that theory in the next module).
Is There One Course of Development or Many?
Is development essentially the same, or universal, for all children (i.e., there is one course of development) or does development follow a different course for each child, depending on the child’s specific genetics and environment (i.e., there are many courses of development)? Do people across the world share more similarities or more differences in their development? How much do culture and genetics influence a child’s behavior?
Stage theories hold that the sequence of development is universal. For example, in cross-cultural studies of language development, children from around the world reach language milestones in a similar sequence (Gleitman & Newport, 1995). Infants in all cultures coo before they babble. They begin babbling at about the same age and utter their first word around 12 months old. Yet we live in diverse contexts that have a unique effect on each of us. For example, researchers once believed that motor development followed one course for all children regardless of culture. However, childcare practices vary by culture, and different practices have been found to accelerate or inhibit the achievement of developmental milestones such as sitting, crawling, and walking (Karasik, Adolph, Tamis-LeMonda, & Bornstein, 2010).
For instance, let’s look at the Aché society in Paraguay. They spend a significant amount of time foraging in forests. While foraging, Aché mothers carry their young children, rarely putting them down in order to protect them from getting hurt in the forest. Consequently, their children walk much later: They walk around 23–25 months old, in comparison to infants in Western cultures who begin to walk around 12 months old. However, as Aché children become older, they are allowed more freedom to move about, and by about age 9, their motor skills surpass those of U.S. children of the same age: Aché children are able to climb trees up to 25 feet tall and use machetes to chop their way through the forest (Kaplan & Dove, 1987). As you can see, our development is influenced by multiple contexts, so the timing of basic motor functions may vary across cultures. However, the functions are present in all societies.
How Do Nature and Nurture Influence Development?
Are we who we are because of
nature
(biology and genetics), or are we who we are because of
nurture
(our environment and culture)? This longstanding question is known in psychology as the nature versus nurture debate. It seeks to understand how our personalities and traits are the product of our genetic makeup and biological factors, and how they are shaped by our environment, including our parents, peers, and culture. For instance, why do biological children sometimes act like their parents—is it because of genetics or because of early childhood environment and what the child has learned from their parents? What about children who are adopted—are they more like their biological families or more like their adoptive families? And how can siblings from the same family be so different?
We are all born with specific genetic traits inherited from our parents, such as eye color, height, and certain personality traits. Beyond our basic genotype, however, there is a deep interaction between our genes and our environment. Our unique experiences in our environment influence whether and how particular traits are expressed, and at the same time, our genes influence how we interact with our environment (Diamond, 2009; Lobo, 2008). There is a reciprocal interaction between nature and nurture as they both shape who we become, but the debate continues as to the relative contributions of each.
Modification, adaptation, and original content.
Authored by
: Margaret Clark-Plaskie for Lumen Learning.
Provided by
: Lumen Learning.
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CC BY: Attribution


11.5: Clean Air
While air pollution is certainly a contributor to climate change via GHGs, it also harms human health in other ways. Air pollution is generated both by natural (biogenic) and human (anthropogenic) sources. Wildfires and volcanoes can spew particulate matter into the air, while vehicle emissions and industrial pollutants produce smog and other gasses. Some air pollutants also undergo chemical reactions when exposed to sunlight which create harmful ground level ozone. Wind currents and water vapor can carry pollutants miles away from their original source. The WHO asserts that both ambient (outdoor) and indoor air pollution contribute to over 7 million deaths around the world each year (WHO, 2019).
The Clean Air Act of 1970 regulates air pollution by empowering the Environmental Protection Agency (EPA) to set and enforce air quality standards. There are six pollutants for which the EPA sets National Ambient Air Quality Standards (NAAQS) for, which are called criteria pollutants. These include carbon monoxide, sulfur dioxide, nitrogen oxide, particulate matter, ozone, and lead. In 1990 the Clean Air Act was amended to include another category of hazardous air pollutants , such as volatile organic compounds (VOCs), pesticides, herbicides, and radionuclides (Frumkin, 2016). The Agency for Toxic Substances and Disease Registry (ATSDR), an agency of the U.S. Department of Health and Human Services, responds to potential toxic emergencies, assists local public health departments, conducts research, and maintains a registry with toxicological profiles of the health effects of natural and man-made hazardous substances that affect our soil, water, and air (ATSDR, 2024).
Primary air pollution is released straight from its source. For example, carbon monoxide is released from motor vehicle exhaust and the combustion of fossil fuels in power plants. It is also released in smoke from forest fires, and is present in environmental (or “second-hand”) tobacco smoke. When other compounds like nitrogen oxides and sulfur dioxide are exposed to sunlight, they can undergo chemical reactions that create ozone and particulate matter. These subsequent pollutants are called secondary air pollution. Thus, air quality is often worse on warm, sunny, summer days than on colder, winter days (Frumkin, 2016, Seabert et al., 2021).
Ozone is both beneficial and hazardous to human health depending on where it exists. In the stratosphere (upper layer of Earth’s atmosphere), ozone blocks harmful UV rays from the sun and protects humans, plants, and animals below - preventing things like skin cancer and cataracts. Compounds called chlorofluorocarbons (CFCs) were used extensively in the mid-20th century to make aerosol propellants, for refrigerators, and in building materials, but these and other pollutants were found to be depleting the ozone layer. Fortunately, in 1987, the Montreal Protocol was signed and countries began phasing out production of ozone depleting substances. Scientists predict that it will be completely repaired by the middle of the 21st century (EPA, 2023). Ground level ozone (in the troposphere) on the other hand, is quite harmful to humans, plants and animals. It can damage the heart and lungs and lead to a variety of chronic diseases (USGCRP, 2023a). Ozone can also be worse in the summer months as a layer of warm air called an inversion layer will trap pollution closer to ground level instead of letting it disperse upward into the stratosphere (Seabert et al., 2021).
Particulate matter is made up of very fine particles of dust, soot, and other solids or liquids of varying sizes. When breathing through the nose, larger particles are typically caught in the nose and upper respiratory system, trapped in mucus and expelled in coughs and sneezes. However, fine particulate matter, or PM2.5 (particulate matter smaller than 2.5 micrometers) can get inhaled much deeper into the lungs and cause damage to lung tissue, as well as increasing the risks of cardiovascular and neurological issues (USGCRP, 2023a). Particulate matter comes from dust, smoke, industrial pollution, vehicle emissions, pollen, and even sea-spray (Frumkin, 2016). We often see particulate matter in the air as smog or brownish haze, hovering over a city-scape on a sunny day.
Air pollution disparately affects minoritized communities including people of color and those of lower socioeconomic status, both in urban and rural areas. This can often be connected to policies and practices such as redlining, as well as industrial zoning. Exhaust from diesel trucks and industrial facilities can be much higher in urban areas, whereas rural areas may be more exposed to pollution from agricultural practices - such as dust and pesticides from crops, or emissions from concentrated animal feeding operations (aka “factory farms). Power plants also release air pollution as well as GHGs. Air quality is made worse by climate change, particularly during heat waves, which may create more secondary air pollution (USGCRP, 2023a).
While the EPA monitors and regulates ambient air pollution, it does not have the same oversight of indoor air pollution. Indoor air pollution can come from building materials, insulation, environmental tobacco smoke, and burning wood, coal, kerosene and even natural gas for cooking or warmth. Mold, mildew, pet dander and dust can also cause respiratory problems. Household cleaning products can release VOCs, which can be particularly harmful to the respiratory system if certain compounds are mixed and then inhaled. Improperly vented combustion for cooking or heating releases carbon monoxide, nitrogen oxides, and particulate matter into the household air. Radon is a radioactive gas that is released from uranium-rich rocks, and can seep into cracks in a home’s foundation and cause lung cancer. Switching to cleaner fuel sources for cooking (such as electricity), removing sources of pollution (such as environmental tobacco smoke), using appropriate ventilation when using cleaners or solvents, and using central ventilation and air conditioning (HVAC) filters or portable air filters are all ways to reduce indoor air pollutants. Additionally, any home improvement projects done on old houses should first be tested for asbestos and lead - as these were commonly used in building materials in the 20th century (EPA, 2014). According to the WHO, 2.3 billion people around the world still use solid fuel for cooking (such as wood, charcoal, and dung), exposing mostly women and children to high levels of air pollution and increasing the risk of respiratory and cardiovascular diseases, cancers, and some infectious diseases as well. In low and middle-income countries, efforts can be made to move toward cleaner fuel sources, such as natural gas and electricity, which would improve air quality, reduce GHGs, and improve health equity (WHO, 2023).
This home’s interior, though beautiful, houses a potential hazard on many levels, therefore, special care need be taken in order to safely operate this wood-burning stove, for not only does it generate a terrific amount of heat, it does so using flame, rather than electricity, which is much more difficult to control. This woman was about to place what appears to be a piece of treated lumber (which can also release harmful pollutants) into the stove as fuel.


In this unit, Dr. Kanatawakhon-Maracle speaks eloquently about how vital each Indigenous language is to the identity of each First Nation, and about the long-term effects of colonization by the English and the French.
A YouTube element has been excluded from this version of the text. You can view it online here:
https://ecampusontario.pressbooks.pub/essentialsoflinguistics/?p=235
Video Script
Canada is a bilingual country … and I think if Canada learns to extend itself, we’ll start including more and more Aboriginal languages. I think Canada is, would be better to tout itself as a multilingual country. Because I think when doing that, even if they, if their definition of multilingualism is, is the two founding languages and then the Indigenous languages, you’re still looking at you know like fifty-five languages. And then because the difference, I think too, Native people have to be included in all that because we were here when English and French showed up. Okay, English and French showed up and they created the present-day institutions and stuff like that, okay fine. Everybody else who has come to this country basically has read the brochure and understood that English or French are the languages, therefore come to this country understanding that, okay I’m going to have to learn English or French because that’s how the company is organized, country is organized. Or if maybe I’ll go learn an Indigenous language as well. But the Indigenous languages have to be at the table.
[CA: The English and French arrived and didn’t say oh well we’re gonna have to learn the language that people speak — they said we’re here, now you’re gonna speak our language.]
Yeah, but you know initially they did learn our languages to deal with us because they didn’t have much choice. We had what they didn’t have and when we got to a point where we no longer had what they wanted, and of course, they wanted the land which meant pushing us off anyway, so the respect for the languages and stuff, kind of went out the door. Then it became well everybody here speaks English only. … I find that we need we need to have the languages. I think that gives us a greater sense of who we are — the language!
And, and the thing is that for, for Native people in this country we have spent so many years under the colonial thumb and so many years being convinced that our own languages and our traditions and everything that’s about us is inferior or not as good as …  If I focus on speaking Mohawk then in the process of learning my language I’m also learning Mohawk culture and what it is to be a Mohawk person and that’s, I think is something that is very important. We’ve gotten into the habit of being Indians or Natives or Aboriginals or Indigenous. Nowadays the word’s ‘Indigenous’. I think I keep telling my students, I said you know, I said, when I was born I was born an Indian but then I became a Native and then I became Aboriginal and then I became First Nations and now I’m Indigenous, yay! You know, Indigenous is the word of the 21st century and I’m sure they’ll find another one, but the word I would really like them to find and stick to is Mohawk, Oneida, Ojibwe, Chippewa. Know us by our nationalities, know us by our distinct cultures, know us by what makes us unique in the world.


15.0: Transitions from Augustan Literature to the Romantics
The Transition between the Augustan period and the Romantic period was a drastic shift in literary ideals. The Augustans followed the works of former classical writers, such as Horace, Virgil, and Homer. To them this was the proper and only way to write. They followed the views of Aristotle, which led them to an empirical way of teaching.
The beginning of the romantic period was marked by the writers, William Wordsworth and Samuel Coleridge. In 1798, when they published Lyrical Ballads . This started the idea that it was intuition within the writer that made them a good poet. The romantics saw writers to be similar to the common man, but with a higher sense of the natural world. They threw out the manuals and empirical way of teaching that was once set in place by the Augustan writers and found that using imagination and deep thought, one could find the truth in the world.
Some characteristics of Augustan poetry are:
- response against rival authors
- the concept of individualism versus society
- the imitation of the classics
- politics and social issues
- satire and irony
- empiricism
- comedy
Some characteristics of Romantic poetry are:
- prominent role of the poet
- the importance of the imagination nature
- the use of emotion
- ordinary subjects
- interest in the spiritual or supernatural
- Transitions from Augustan Literature to the Romantics. Authored by : Julie Wigley. Provided by : BritLitWiki. Located at : https://britlitwiki.wikispaces.com/Transitions+from+Augustan+Literature+to+the+Romantics . License : CC BY-SA: Attribution-ShareAlike


28.6: Review Questions
A nurse is assessing a client for type 1 diabetes. Which of the following findings should the nurse expect if the client does, in fact, have diabetes?
- Answer
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Glycosylated hemoglobin 6.8%
A nurse is developing an education plan for a client with diabetes in regard to an insulin pump. Which of the following should the nurse include in the education plan?
- Answer
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Teach the client to recognize symptoms of hypoglycemia
A nurse is administering regular insulin to a client with diabetes. After administering the correct dose at 6:30 a.m., the nurse should ensure the client receives breakfast at which of the following times?
- Answer
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7 a.m.
A nurse is caring for a client with type 1 diabetes who is being prescribed a long-acting insulin. The nurse identifies which of the following as a long-acting insulin?
- Answer
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Insulin glargine
A nurse is teaching a client with diabetes about a new prescription for insulin isophane NPH. Which of the following instructions should the nurse include in the teaching?
- Answer
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Eat a snack 7 hours after taking the insulin isophane NPH.
A nurse is caring for a client with diabetes who has a blood glucose of 50 mg/dL and is semiconscious and having difficulty swallowing. Which of the following actions should the nurse take?
- Answer
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Administer glucagon
A nurse is preparing to administer 15 units of regular insulin and 23 units of NPH insulin subcutaneously. What is the total number of units of insulin that the nurse should prepare in the insulin syringe?
- Answer
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38 units
Which of the following insulins can be administered via an insulin pump?
- Answer
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Insulin aspart
A 76-year-old client with diabetes and renal impairment is scheduled for a diagnostic test requiring the use of contrast dye. Which of the following drugs should the nurse instruct the client to stop taking 24 hours prior to the procedure?
- Answer
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Metformin
A nurse received a health care provider’s order to administer 750 mg of metformin twice daily to a client. Metformin is available in 500 mg tablets. How many tablets will the nurse administer per dose?
- Answer
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1.5 tablets


14.2: Forces that Shape the Surface of the Earth
In Chapter 2 you were introduced to sources of energy that drive earth system processes. The lithosphere is constantly being altered by these forces originating from within and outside the Earth system. Great forces from within causes the surface to heave and buckle, sometimes with disastrous consequences to humans. Energy received from the sun drives processes like those that create majestic sand dunes and carve magnificent stream valleys.
Endogenic Processes and the Lithosphere
Recall that endogenic forces or processes are those that are are driven by the Earth's vast heat engine. The movement of tectonic plates is thought to be a product of convection currents in the mantle. Deep within the Earth's core, heat is generated by the radioactive decay of elements like uranium, thorium, and potassium. The heat is transferred upward to warm the mantle causing it to slowly circulate and tug on the plates above. (For more see Some Unanswered Questions , The Dynamic Earth , USGS). As the crustal plates are moved about, they interact by colliding, sliding by, or diverging from one another. The result of such movement produces faults and earthquakes, volcanoes, the creation of mountain systems, or deep valleys and trenches. The great mountain systems of Earth like the Himalayas are a product of the collision of lithospheric plates. Similarly, the huge trenches found on the ocean floor, like the Marianas Trench, are caused by plate interaction.
Exogenic Processes and the Lithosphere
Those processes acting at the surface of the earth and primarily driven by solar energy are called exogenic processes . For instance, wind is created by the variation in pressure over distance (pressure gradient force). Pressure variations are, in part, created by the variation of surface heating due to the unequal distribution of solar energy receipt. As wind blows it exerts an erosive force on the surface to detach and transport soil particles. Wind erosion is therefore an exogenic process. Erosion by rain is likewise driven by the initial evaporation due to absorption of energy and subsequent conversion into precipitation by condensation processes. The geologic work of glaciers is considered an exogenic process. Glaciers form when summer temperatures decrease to the point where the previous winter's snowfall does not melt and accumulates over time eventually compacting and metamorphosing into ice. The accumulating ice spreads out as a great sheet sculpting the surface beneath it.


3.1.1: How Well Can You Measure?
Lesson
Let's see how accurately we can measure.
Exercise \(\PageIndex{1}\): Estimating a Percentage
A student got 16 out of 21 questions correct on a quiz. Use mental estimation to answer these questions.
- Did the student answer less than or more than 80% of the questions correctly?
- Did the student answer less than or more than 75% of the questions correctly?
Exercise \(\PageIndex{2}\): Perimeter of a Square
Your teacher will give you a picture of 9 different squares and will assign your group 3 of these squares to examine more closely.
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For each of your assigned squares, measure the length of the diagonal and the perimeter of the square in centimeters.
Check your measurements with your group. After you come to an agreement, record your measurements in the table.diagonal (cm) perimeter (cm) square A square B square C square D square E square F square G square H square I Table \(\PageIndex{1}\) - Plot the diagonal and perimeter values from the table on the coordinate plane.
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What do you notice about the points on the graph?
Pause here so your teacher can review your work. - Record measurements of the other squares to complete your data.
Exercise \(\PageIndex{3}\): Area of a Square
1. In the table, record the length of the diagonal for each of your assigned squares from the previous activity. Next, calculate the area of each of your squares.
| diagonal (cm) | area (cm 2 ) | |
|---|---|---|
| square A | ||
| square B | ||
| square C | ||
| square D | ||
| square E | ||
| square F | ||
| square G | ||
| square H | ||
| square I |
Pause here so your teacher can review your work. Be prepared to share your values with the class.
2. Examine the class graph of these values. What do you notice?
3. How is the relationship between the diagonal and area of a square the same as the relationship between the diagonal and perimeter of a square from the previous activity? How is it different?
Are you ready for more?
Here is a rough map of a neighborhood.
There are 4 mail routes during the week.
- On Monday, the mail truck follows the route A-B-E-F-G-H-A, which is 14 miles long.
- On Tuesday, the mail truck follows the route B-C-D-E-F-G-B, which is 22 miles long.
- On Wednesday, the truck follows the route A-B-C-D-E-F-G-H-A, which is 24 miles long.
- On Thursday, the mail truck follows the route B-E-F-G-B.
How long is the route on Thursdays?
Summary
When we measure the values for two related quantities, plotting the measurements in the coordinate plane can help us decide if it makes sense to model them with a proportional relationship. If the points are close to a line through \((0,0)\), then a proportional relationship is a good model. For example, here is a graph of the values for the height, measured in millimeters, of different numbers of pennies placed in a stack.
Because the points are close to a line through \((0,0)\), the height of the stack of pennies appears to be proportional to the number of pennies in a stack. This makes sense because we can see that the heights of the pennies only vary a little bit.
An additional way to investigate whether or not a relationship is proportional is by making a table. Here is some data for the weight of different numbers of pennies in grams, along with the corresponding number of grams per penny.
| number of pennies | grams | grams per penny |
|---|---|---|
| \(1\) | \(3.1\) | \(3.1\) |
| \(2\) | \(5.6\) | \(2.8\) |
| \(5\) | \(13.1\) | \(2.6\) |
| \(10\) | \(25.6\) | \(2.6\) |
Though we might expect this relationship to be proportional, the quotients are not very close to one another. In fact, the metal in pennies changed in 1982, and older pennies are heavier. This explains why the weight per penny for different numbers of pennies are so different!
Practice
Exercise \(\PageIndex{4}\)
Estimate the side length of a square that has a 9 cm long diagonal.
Exercise \(\PageIndex{5}\)
Select all quantities that are proportional to the diagonal length of a square.
- Area of the square
- Perimeter of the square
- Side length of the square
Exercise \(\PageIndex{6}\)
Diego made a graph of two quantities that he measured and said, “The points all lie on a line except one, which is a little bit above the line. This means that the quantities can’t be proportional.” Do you agree with Diego? Explain.
Exercise \(\PageIndex{7}\)
The graph shows that while it was being filled, the amount of water in gallons in a swimming pool was approximately proportional to the time that has passed in minutes.
- About how much water was in the pool after 25 minutes?
- Approximately when were there 500 gallons of water in the pool?
- Estimate the constant of proportionality for the gallons of water per minute going into the pool.


4.7: Module Learning Activities
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- Ernstmeyer & Christman (Eds.)
- Chippewa Valley Technical College via OpenRN
Lightbulb Moment
Test your knowledge and application.
Practice applying your knowledge regarding ANS neuroreceptors to the following patient scenarios where a nurse must use clinical judgment for a solution:
1. A patient begins a nicotine patch in an attempt to stop smoking. The patient reports feelings of nausea, weakness, and a rapid heartbeat. What is the likely cause of these symptoms, and what is the nurse’s best response?
2. A patient with benign prostatic hyperplasia (BPH) has a new order for tamsulosin. He asks, “How will tamsulosin help me? I already take so many pills.”
a) What is the nurse’s best response?
b) What does the nurse plan to monitor carefully, especially after administering the first dose of tamsulosin?
3. A patient with asthma is taking albuterol to help when she feels increased shortness of breath.
a) How will albuterol assist in her breathing?
The patient states, “After I take albuterol, it feels like my heart is racing.”
b) What is the likely cause of this symptom?
c) What is the nurse’s best response to the patient’s concern?
4. A patient with high blood pressure is prescribed propranolol.
a) How will propranolol help to lower his blood pressure?
b) What will the nurse assess before administering the propranolol?
The nurse listens to the patient’s lungs a few hours after administering propranolol and notices new wheezing.
c) What could be a potential cause of this new finding?
d) What is the nurse’s next best response?
5. A patient is prescribed metoprolol to help control his atrial fibrillation, an irregular heart rhythm.
a) What will the nurse assess before administering the metoprolol?
b) What findings would cause the nurse to call the provider before administering the metoprolol?
Upon reassessment the next day, the nurse notices a new finding of edema in the patient’s feet and lower legs.
c) What could be a potential cause of this new finding?
d) What is the nurse’s next best response?
6. A patient with an acute episode of heart failure is admitted and is prescribed dobutamine.
a) How will dobutamine improve the patient’s condition?
b) What will the nurse monitor carefully during administration?
Note: Answers to the Light Bulb Moment can be found in the “Answer Key” sections at the end of the book.


6.4: Sound
Sound is a form of energy transmitted through pressure waves; longitudinal or compressional waves similar to the seismic P-waves we discussed in section 3.3. With ocean sounds, the energy is transmitted via water molecules vibrating back and forth parallel to the direction of the sound wave, and passing on the energy to adjacent molecules. Therefore, sound travels faster and more efficiently when the molecules are closer together and are better able to transfer their energy to neighboring particles. In other words, sound travels faster through denser materials. Since water is much denser than air, the speed of sound in water (about 1500 m/s) is approximately five times faster than the speed in air (around 330 m/s). This helps explain why we sometimes have difficulty localizing the source of a sound that we hear underwater. We localize sound sources when our brains detect the tiny differences in the time of arrival of sounds reaching our ears. A sound coming from our left will reach our left ear a fraction of a second before reaching our right ear. Our brains can process that small difference in time of arrival to recognize the direction from which the sound came. In water, the sound is so much faster that the difference in arrival time between our ears becomes too small for us to interpret, and we lose the ability to localize the source.
However, as with sound in air, the speed of sound in the ocean is not constant; it is influenced by a number of variables including temperature, salinity, and pressure, and an increase in any of these factors will lead to an increase in the speed of sound. We have seen that these variables change with depth and location; so to will the speed of sound differ in different regions of the ocean.
To examine the way the speed of sound changes as a function of depth, we need to consider the vertical profiles for temperature and pressure. At the surface, the pressure is low, but the temperature is at its highest point in the water column. The temperature effects dominate at the surface, so the speed of sound is fast in surface waters. As depth increases, the temperature and the speed of sound decline. Near the bottom, the extreme pressure dominates, and even though temperatures are low, the speed of sound increases with depth. At moderate depths (between a few hundred and one thousand meters) there is a zone where both temperature and pressure are relatively low, so the speed of sound is at a minimum. This zone of minimum speed is called the SOFAR channel ( So und F ixing A nd R anging) or the Deep Sound Channel (Figure \(\PageIndex{1}\)).
The SOFAR channel is important because sounds produced in that region can be propagated over very long distances with little attenuation (loss of energy). Sound waves produced in the channel radiate out in all directions. Waves that travel into shallower or deeper water outside of the sound channel are entering a region of faster sound transmission. As we saw with seismic waves, when these sound waves encounter a region of differing transmission speed, the waves tend to be refracted or bent back towards the region of lower speed. As a result, sound waves moving from the SOFAR channel into shallower water will be refracted back towards the channel. As the sound waves go deeper below the channel, they will be refracted upwards, back into the channel and the region of slower speed. In this way, much of the sound does not dissipate out into the water in all directions, but instead is trapped within the channel, and can travel very long distances with little loss of energy (Figure \(\PageIndex{2}\)).
There are several practical applications of the SOFAR channel. Baleen whales are thought to use the SOFAR channel to communicate with each other over long distances of hundreds to thousands of kilometers. Their vocalizations are very loud and are low frequency calls, which travel farther than high frequency sounds in the oceans. The military has been able to track submarines using the SOFAR channel, and during World War II it was used to locate downed pilots or missing ships and planes. A stranded pilot could drop a small device into the water, and once it sank into the SOFAR channel it would explode, creating a sound that could be heard at multiple listening stations. Using the time of arrival of the sound at the various receivers, the location of the source could be determined through triangulation. In the 1990s it was suggested that the SOFAR channel could be used to monitor global ocean temperatures. A project known as ATOC (Acoustic Thermometry of Ocean Climate) was proposed where loud, low frequency sounds produced near Hawaii and California would travel through the SOFAR channel to receiving stations around the Pacific. By monitoring the time it took for the sounds to reach the receivers, scientists could monitor changes in ocean temperatures on a global scale, as sounds would move faster through a warming ocean.
Since sound travels better through water than air, the energy required to transmit a given sound wave is higher in air than in water. The energy, or intensity (loudness) of a sound is measured on the decibel (dB) scale. It turns out that it takes about 61 times more energy to transmit a sound through air than through water. Because of this energy difference, there is a 61 dB difference between sounds transmitted through air and water, such that a sound intensity of 120 dB in water would be equivalent to an intensity of about 60 dB in air. This should be kept in mind when trying to compare sounds in the ocean with sounds in the air. A sound of 130 dB in air is about equivalent to standing 100 m from a jet engine at takeoff. A sound of 130 dB in water is equivalent to about 70 dB in air, which is the intensity of the sound of a vacuum cleaner. It should also be pointed out that on the dB scale, an increase of 10 dB means the sound is 10 times louder. In other words, 20 dB is 10 x louder than 10 dB, while 30 dB is 100 x louder than 10 dB.
- Discovery of Sound in the Sea website: http://www.dosits.org/


10.9: Grit- Getting Things Done!
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Another specific trait that has become somewhat popular recently in higher education has been called grit by Angela Duckworth and her colleagues (see Duckworth et al., 2007). Grit is defined as the perseverance and passion necessary to accomplish long-term goals. In particular, it refers to the ability to continue striving toward those goals despite temporary failure, adversity, and plateaus in one's progress. Although much of the research on grit has focused on academic goals, grit does not correlate well with intelligence. Rather, it correlates highly with the Big-Five trait of conscientiousness.
 However, Anders Ericsson proposed and studied a different theoretical framework. Although an individual may show some early talent in a particular domain, what resulted in their becoming an expert, or a star athlete, was the intensive deliberate practice that followed, often taking many years before the individual truly excelled (Ericsson, 2004; Ericsson et al., 1993). Working together, Duckworth, Ericsson, and a few of their colleagues showed that deliberate practice is the key to success in an academic competition that tends to fascinate many people because of just how difficult it is: the National Spelling Bee (Duckworth et al., 2010).
Whether it's grit, consciousness, or the associated behavior of deliberate practice, those who continue to strive toward their goals tend to succeed not only in school, but also in most aspects of life, including life satisfaction and earning a good income (Duckworth & Carlson, 2013; Duckworth et al., 2012). But what can, perhaps, interfere with one's ability and/or motivation to continue striving toward one's goals? It appears that life stress in early adolescence can significantly impair one's ability to strive toward a positive and fruitful future (Duckworth et al., 2013). It's quite possible that since adolescence is the time of developing one's identity, according to Erik Erikson, and identity associated with negative life events and stress is incompatible with maintaining grit.
As I mentioned above, this is an area only recently becoming well-known (i.e., popular) in the field of higher education. It is likely to become an increasingly significant factor in how we work toward helping students achieve their goals, whether academic or in other aspects of their lives.
Final Note: Moving Toward a New “Big Five”?
In 2006, Dan McAdams and Jennifer Pals argued that personality psychology has failed to provide a comprehensive framework in which we can understand the whole person. Since this was a guiding principle of many of the founders of this field, an effort to combine recent research with early principles would help the field of personality psychology move toward maturity. In a manner similar to Costa and McCrae’s Five-Factor Theory, McAdams and Pals suggest that those who study personality should be guided by five fundamental principles: evolutionary design, dispositional traits, characteristic adaptations, integrative life narrative, and culture. Their examination of these principles led them to the following definition of personality:
Personality is an individual’s unique variation on the general evolutionary design for human nature, expressed as a developing pattern of dispositional traits, characteristic adaptations, and integrative life stories complexly and differentially situated in culture. (pg. 212; McAdams & Pals, 2006)
If personality psychologists use these principles in their ongoing efforts to understand each individual, they should be able to achieve an understanding of an old paradox offered to explain personality: every person is like every other person, like some other persons, and like no other person (see McAdams & Pals, 2006).


2.4: Calculation of Work
In thermodynamics, work (\(W\)) is the ability of a system to transfer energy by exerting a force on its surroundings. Work can be measured simply by evaluating its effects, such as displacing a massive object by some amount of space. The mathematical treatment of work, however, is complicated because work is a path function . In the following sections, we will analyze how work is calculated in some prototypical situations commonly encountered in the thermodynamical treatment of systems.
Let’s consider the situation in Figure \(\PageIndex{1}\), where a special beaker with a piston that is free to move is filled with an ideal gas. The beaker sits on a desk, so the piston is not subject to any external forces other than the external pressure, \(P_{\text{ext}}\), and the internal pressure of the gas, \(P\). 1 The piston is initially compressed to a position that is not in equilibrium \((i)\). After the process, the piston reaches a final equilibrium position \((f)\). How do we calculate the work (\(W\)) performed by the system?
From basic physics, we recall that the infinitesimal amount of work associated with an object moving in space is given by the force acting on the object (\(F\)) multiplied by the infinitesimal amount it gets displaced (\(d h\)):
\[ đ W = - Fdh, \label{2.4.1} \]
where the negative sign comes from the chemistry sign convention, Definition: System-centric , since the work in Figure \(\PageIndex{1}\) is performed by the system (expansion). What kind of force is moving the piston? It is the force due to the pressure of the gas. Relying upon another definition from physics, the pressure is the ratio between the force (\(F\)) and the area (\(A\)) that such force acts upon:
\[ P = F/A. \label{2.4.2} \]
Obtaining \(F\) from Equation \ref{2.4.2} and replacing it in Equation \ref{2.4.1}, we obtain:
\[ đ W - P \underbrace{Adh}_{dV}, \label{2.4.3} \]
and considering that \(Adh\) (area times infinitesimal height) is the definition of an infinitesimal volume \(dV\), we obtain:
\[ đ W = - PdV, \label{2.4.4} \]
If we want to calculate the amount of work performed by a system, \(W\), from Equation \ref{2.4.4}, we need to recall that \(đ W\) is an inexact differential. As such, we cannot integrate it from initial to final as for the (exact) differential of a state function, because:
\[ \int_{i}^{f}đ W \neq W_f - W_i, \label{2.4.5} \]
but rather:
\[ \int_{\text{path}} đ W = W, \label{2.4.6} \]
where the integration is performed along the path . Using Equation \ref{2.4.6}, we can integrate Equation \ref{2.4.4} as:
\[ \int đ W = W = - \int_{i}^{f} PdV, \label{2.4.7} \]
where the integral on the left-hand side is taken along the path, 2 while the integral on the right-hand side can be taken between the initial and final states, since \(dV\) is a state function. How do we solve the integral in Equation \ref{2.4.7}? It turns out that there are many different ways to solve this integral (perhaps not surprisingly, since the left-hand side depends on the path), which we will explore in the next section.
\(| W_{\text{max}} |\) and \(| W_{\text{min}} |\) in processes at constant temperature (isothermal)
At constant temperature, the piston in Figure \(\PageIndex{1}\) moves along the following PV diagram (this curve is obtained from an ideal gas at constant \(T=298\) K):
An expansion of the gas will happen between \(P_i\) and \(P_f\). If the expansion happens in a one-step fast process, for example against external atmospheric pressure, then we can consider such final pressure constant (for example \(P_f=P_{\text{ext}} =1\;\mathrm{bar}\)), and solve the integral as:
\[ W_{\text{1-step}} = - \int_{i}^{f} P_{\text{ext}}dV = -P_{\text{ext}} \int_{i}^{f} dV = -P_{\text{ext}} (V_f-V_i), \label{2.4.8} \]
Notice how the work is negative, since during an expansion the work is performed by the system (recall the chemistry sign convention). The absolute value of the work 3 represents the red area of the PV-diagram:
\[ \left| W_{\text{1-step}} \right| = P_{\text{ext}} (V_f-V_i) \label{2.4.9} \]
If the process happens in two steps by pausing at an intermediate position (1) until equilibrium is reached, then we should calculate the work by dividing it into two separate processes, \(A\) and \(B\), and solve each one as we did in the previous case. The first process is an expansion between \(P_i\) and \(P_1\), with \(P_1\) constant. The absolute value of the work, \(W_A\), is represented by the blue area:
\[ \left| W_A \right| = P_1 (V_1-V_i) \label{2.4.10} \]
The second process is an expansion between \(P_1\) and \(P_f\), with \(P_f=P_{\text{ext}}\) constant. The absolute value of the work for this second process is represented by the green area:
\[ \left| W_B \right| = P_f (V_f-V_1) \label{2.4.11} \]
The total absolute value of the work for the 2-step process is given by the sum of the two areas:
\[ \left| W_{\text{2-step}} \right| = \left| W_A \right| + \left| W_B \right| = P_1 (V_1-V_i)+P_f (V_f-V_1). \label{2.4.12} \]
As can be easily verified by comparing the shaded areas in the plots, \(\left| W_{\text{2-step}} \right| > \left| W_{\text{1-step}} \right|\).
We can easily extend this procedure to consider processes that happens in 3, 4, 5, …, \(n\) steps. What is the limit of this procedure? In other words, what happens when \(n \rightarrow \infty\)? A simple answer is given by the plots in the next Figure, which clearly demonstrates that the maximum value of the area underneath the curve \(\left| W_{\text{max}}\right|\) is achieved in an \(\infty\)-step process, for which the work is calculated as:
\[ \left| W_{\infty \text{-step}} \right| = \left| W_{\text{max}} \right| = \sum_{n}^{\infty} P_n(V_n-V_{n-1}) = \int_{i}^{f} PdV. \label{2.4.13} \]
The integral on the right hand side of Equation \ref{2.4.13} can be solved for an ideal gas by calculating the pressure using the ideal gas law \(P=\dfrac{nRT}{V}\), and solving the integral since \(n\), \(R\), and \(T\) are constant:
\[ \left| W_{\text{max}} \right| = nRT \int_{i}^{f} \dfrac{dV}{V} = nRT \ln \dfrac{V_f}{V_i}. \label{2.4.14} \]
This example demonstrates why work is a path function. If we perform a fast 1-step expansion, the system will perform an amount of work that is much smaller than the amount of work it can perform if the expansion between the same points happens slowly in an \(\infty\)-step process.
The same considerations that we made up to this point for expansion processes hold specularly for compression ones. The only difference is that the work associated with compressions will have a positive sign since it must be performed onto the system. As such, the amount of work for a transformation that happens in a finite amount of steps will be an upper bound to the minimum amount of work required to compress the system. 4 \(\left| W_{\text{min}} \right|\) for compressions is calculated as the area underneath the PV curve, exactly as \(\left| W_{\text{min}} \right|\) for expansions in Equation \ref{2.4.13}.
- For this simple thought experiment, we will ignore any external force that is not significant. In other words, we will not consider the friction of the piston on the beaker walls or any other foreign influence.
- from here on we will replace the notation \(\int_{\text{path}}\) with the more convenient \(\int\) and we will keep in mind that the integral of an inexact differential must be taken along the path.
- we use the absolute value to avoid confusions due to the fact that the expansion work is negative according to Definition: System-centric .
- In contrast to a lower bound for expansion processes.


5.3: Antimicrobial Drugs
In nature, some microbes produce substances that inhibit or kill other microbes that might otherwise compete for the same resources. Humans have successfully exploited these abilities, using microbes to mass-produce substances that can be used as antimicrobial drugs. Since their discovery, antimicrobial drugs have saved countless lives, and they remain an essential tool for treating and controlling infectious disease. But their widespread and often unnecessary use has had an unintended side effect: the rise of multidrug-resistant microbial strains. In this chapter, we will discuss how antimicrobial drugs work, why microbes develop resistance, and what health professionals can do to encourage responsible use of antimicrobials.
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- 5.3.1: Discovering Antimicrobial Drugs
- Antimicrobial drugs produced by purposeful fermentation and/or contained in plants have been used as traditional medicines in many cultures for millennia. The purposeful and systematic search for a chemical “magic bullet” that specifically target infectious microbes was initiated by Paul Ehrlich in the early 20th century. The discovery of the natural antibiotic, penicillin, by Alexander Fleming in 1928 started the modern age of antimicrobial discovery and research.
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- 5.3.2: Antibacterial Drugs
- Antimicrobial drugs can be bacteriostatic or bactericidal, and these characteristics are important considerations when selecting the most appropriate drug. The use of narrow-spectrum antimicrobial drugs is preferred in many cases to avoid superinfection and the development of antimicrobial resistance. Broad-spectrum antimicrobial use is warranted for serious systemic infections when there is no time to determine the causative agent or when narrow-spectrum antimicrobials fail.
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- 5.3.3: Drugs Targeting Other Microorganisms
- Antibacterial compounds exhibit selective toxicity, largely due to differences between prokaryotic and eukaryotic cell structure. Cell wall synthesis inhibitors, including the β-lactams, the glycopeptides, and bacitracin, interfere with peptidoglycan synthesis, making bacterial cells more prone to osmotic lysis. There are a variety of broad-spectrum, bacterial protein synthesis inhibitors that selectively target the prokaryotic 70S ribosome, including those that bind to the 30S and 50S subunits.
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- 5.3.5: Testing the Effectiveness of Antimicrobials
- Antimicrobial resistance is on the rise and is the result of selection of drug-resistant strains in clinical environments, the overuse and misuse of antibacterials, the use of subtherapeutic doses of antibacterial drugs, and poor patient compliance with antibacterial drug therapies. Drug resistance genes are often carried on plasmids or in transposons that can undergo vertical transfer easily and between microbes through horizontal gene transfer.
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- 5.3.6: The Emergence of Drug Resistance
- The Kirby-Bauer disk diffusion test helps determine the susceptibility of a microorganism to various antimicrobial drugs. However, the zones of inhibition measured must be correlated to known standards to determine susceptibility and resistance, and do not provide information on bactericidal versus bacteriostatic activity, or allow for direct comparison of drug potencies. Antibiograms are useful for monitoring local trends in antimicrobial resistance/susceptibility.
Footnotes
- 1 “Treatment of War Wounds: A Historical Review.” Clinical Orthopaedics and Related Research 467 no. 8 (2009):2168–2191.
Thumbnail: Staphylococcus aureus - Antibiotics Test plate. (Public Domain; CDC / Provider: Don Stalons).


1.5: Retribution
Retribution means giving offenders the punishment they deserve. Most adherents to this idea believe that the punishment should fit the offense. This idea is known as the doctrine of proportionality. Such a doctrine was advocated by early Italian criminologist Cesare Beccaria who viewed the harsh punishments of his day as being disproportionate to many of the crimes committed. The term just desert is often used to describe a deserved punishment that is proportionate to the crime committed.
In reality, the doctrine of proportionality is difficult to achieve. There is no way that the various legislatures can go about objectively measuring criminal culpability. The process is one of legislative consensus and is imprecise at best.


The next morning we left Aute,* and traveled all
day before coming to the place I had visited. The
journey was extremely arduous. There were not
horses enough to carry the sick, who went on increas-
ing in numhers day hy day, and we knew of no cure.
It was piteous and painful to witness our perplexity
and distress. "We saw on our arrival how small were
the means for advancing farther. There was not any
where to go ; and if there had been, the people were
unable to move forward, the greater part being ill, and
those were few who could be on duty. I cease here
to relate more of this, because any one may suppose
what would occur in a country so remote and malign,
so destitute of all resource, whereby either to live in
it or go out of it ; but most certain assistance is in Grod,
our Lord, on whom we never failed to place reliance.
One thing occurred, more afflicting to us than all the
rest, which was, that of the persons mounted, the
greater part commenced secretly to plot, hoping to
secure a better fate for themselves by abandoning the
Governor and the sick, who were in a state of weak-
ness and prostration. But, as among them were many
hidalgos and persons of gentle condition, they would
not permit this to go on, without informing the Go-
vernor and the officers of your Majesty; and as we
showed them the deformity of their purpose, and
placed before them the moment when they should
desert their captain, and those who were ill and feeble,
and above all the disobedience to the orders of your
Majesty, they determined to remain, and that whatever
might happen to one should be the lot of all, without
any forsaking the rest.
After the accomplishment of this, the Governor
called them all to him, and of each apart he asked
advice as to what he should do to get out of a country
so miserable, and seek that assistance elsewhere
which could not here be found, a third part of the
people being very sick, and the number increasing
every hour; for we regarded it as certain that we
should all become so, and could pass out of it only
through death, which from its coming in such a place
was to us all the more terrible. These, with many
other embarrassments being considered, and entertain-
ing many plans, we coincided in one great project,
extremely difficult to put in operation, and that was to
build vessels in which we might go away. This ap-
peared impossible to every one : we knew not how to
construct, nor were there tools, nor iron, nor forge,
nor tow, nor resin, nor rigging; finally, no one thing
of so many that are necessary, nor any man who had
a knowledge of their manufacture; and, above all,
there -was nothing to eat, while building, for those who
should labor...
Before we embarked there died more than forty
men of disease and hunger, without enumerating those
destroyed by the Indians. By the twenty-second of
the month of September,* the horses had been con-
sumed, one only remaining ; and on that day we em-
barked in the following order : In the boat of the
Governor went forty-nine men ; in another, which he
gave to the Comptroller and the Commissary, went as
many others ; the third, he gave to Captain Alonzo del
Castillo and Andres Dorantes, with forty-eight men;
and another he gave to two captains, Tellez and Pena^
losa, with forty-seven men. The last was given to the
Assessor and myself, with forty-nine men. After the
provisions and clothes had been taken in, not over a
span of the gunwales remained above water ; and more
than this, the boats were so crowded that we could not
move : so much can necessity do, which drove us to
hazard our hves in this manner, running into a turbu-
lent sea, not a single one who went, having a know-
ledge of navigation.


2.5: Linear Diophantine Equations
In this section, we discuss equations in two variables called diophantine equations. These kinds of equations require integer solutions. The goal of this section is to present the set of points that determine the solution to this kind of equations. Geometrically speaking, the diophantine equation represent the equation of a straight line. We need to find the points whose coordinates are integers and through which the straight line passes.
A linear equation of the form \(ax+by=c\) where \(a,b\) and \(c\) are integers is known as a linear diophantine equation.
Note that a solution to the linear diophantine equation \((x_0,y_0)\) requires \(x_0\) and \(y_0\) to be integers. The following theorem describes the case in which the diophantine equation has a solution and what are the solutions of such equations.
The equation \(ax+by=c\) has integer solutions if and only if \(d\mid c\) where \(d=(a,b)\). If the equation has one solution \(x=x_0\), \(y=y_0\), then there are infinitely many solutions and the solutions are given by \[x=x_0+(b/d)t \ \ \ \ \ y=y_0-(a/d)t\] where \(t\) is an arbitrary integer.
Suppose that the equation \(ax+by=c\) has integer solution \(x\) and \(y\). Thus since \(d\mid a\) and \(d\mid b\), then \[d\mid (ax+by)=c.\] Now we have to prove that if \(d\mid c\), then the equation has integral solution. Assume that \(d\mid c\). By theorem 9, there exist integers \(m\) and \(n\) such that \[d=am+bn.\] And also there exists integer \(k\) such that \[c=dk\] Now since \(c=ax+by\), we have \[c=dk=(ma+nb)k=a(km)+b(nk).\] Hence a solution for the equation \(ax+by=c\) is \[x_0=km \ \ \mbox{and} \ \ y_0=kn.\] What is left to prove is that we have infinitely many solutions.  We have to prove now that \(x\) and \(y\) are solutions for all integers \(t\). Notice that \[ax+by=a(x_0+(b/d)t)+b(y_0-(a/d)t)=ax_0+by_0=c.\] We now show that every solution for the equation \(ax+by=c\) is of the form \[x=x_0+(b/d)t \mbox{and} \ \ y=y_0-(a/d)t.\] Notice that since \(ax_0+by_0=c\), we have \[a(x-x_0)+b(y-y_0)=0.\] Hence \[a(x-x_0)=b(y-y_0).\] Dividing both sides by \(d\), we get \[a/d(x-x_0)=b/d(y-y_0).\] Notice that \((a/d,b/d)=1\) and thus we get by Lemma 4 that \(a/d\mid y-y_0\). As a result, there exists an integer \(t\) such that \(y=y_0-(a/d)t\). Now substituting \(y-y_0\) in the equation \[a(x-x_0)=b(y-y_0).\] We get \[x=x_0+(b/d)t.\]
The equation \(3x+6y=7\) has no integer solution because \((3,6)=3\) does not divide \(7\).
There are infinitely many integer solutions for the equation \(4x+6y=8\) because \((4,6)=2 \mid 8\). We use the Euclidean algorithm to determine \(m\) and \(n\) where \(4m+6n=2\). It turns out that \(4(-1)+6(1)=2\). And also \(8=2.4\). Thus \(x_0=4.(-1)=-4\) and \(y_0=4.1=4\) is a particular solution. The solutions are given by \[x=-4+3t \ \ \ \ \ y=4-2t\] for all integers \(t\).
Exercises
- Either find all solutions or prove that there are no solutions for the diophantine equation \(21x+7y=147.\)
- Either find all solutions or prove that there are no solutions for the diophantine equation \(2x+13y=31.\)
- Either find all solutions or prove that there are no solutions for the diophantine equation \(2x+14y=17.\)
- A grocer orders apples and bananas at a total cost of $8.4. If the apples cost 25 cents each and the bananas 5 cents each, how many of each type of fruit did he order.
Contributors and Attributions
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Dr. Wissam Raji, Ph.D., of the American University in Beirut. His work was selected by the Saylor Foundation’s Open Textbook Challenge for public release under a Creative Commons Attribution ( CC BY ) license.


5.1.6: Some Issues for Modern Africa
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In a fascinating book entitled Education for Self-Reliance , Julius Nyerere (1967) discussed the importance of building the post-colonial educational system in Tanzania. A fundamental premise, according to Nyerere, is that the educational system needed to serve the goals of Tanzania (see also Gichuru, 2005; Khoapa, 1980). Therefore, they had to decide what kind of society they were building. He said their society was based on three principles: equality and respect for human dignity, sharing of resources, and work by everyone and exploitation by none. Interestingly, these principles do not focus on academic content. The successful community life of the village was more important. Social goals, the common good, and cooperation were all emphasized over individual achievement. Nyerere considered it particularly important to avoid intellectual arrogance, so that those who became well educated would not despise those whose skills were non-academic. “Such arrogance has no place in a society of equal citizens” (pg. 8; Nyerere, 1967).
The aim of education in Tanzania became one in which students were to realize they were being educated by the community in order to become intelligent and active members of the community. Since education is provided at the expense of the community, the community is well within its rights to expect those students to become leaders and innovators, to make significantly greater contributions to the community than if they had not received an education (Bennaars, 2005; Sanyal & Kinunda, 1977). To this end, the training of teachers places ideology ahead of content. Student-teachers are taught: 1) the true of meaning of the Tanzanian concept of ujamaa (familyhood and socialism; a basis for planned, self-contained villages), 2) to be dedicated and capable teachers who understand and care for the children in their charge, and 3) to deepen the students’ general education. Since colonial rulers exploited, humiliated, and ignored the people of Africa for so long, it was believed that teachers should be of sound mind and sound body. Thus, admission into a teacher training program requires a good academic background, sound character, physical fitness, and a good all-around background (Mmari, 1979). Thus, teachers were trained to be good role models for the development of Tanzania and her people (see also Bennaars, 2005; Mbalia, 1995).
discussion question \(\PageIndex{1}\)
In post-colonial Africa, some countries trained their teachers to educate children in being good citizens, and to be role models for how children should live their lives. Do you agree that teachers should play such an intentional role in helping to raise children? If not, does it seem that this was necessary for a time, given the history of colonization in Africa?
Although most of the work covered in this section has been done by writers, anthropologists, and sociologists, is there a role for more formalized personality testing in Africa? While this may not be the ideal approach for studying personality in African, it would allow us to compare this work with our Western concepts of personality (which constitutes the large majority of this book). There is preliminary evidence that the Five-Factor Model applies well when measuring the personality traits of Africans in Zimbabwe and South Africa (McCrae, 2002; Piedmont et al., 2002). Tembo (1980) developed an African Personality Scale on which Zambian college freshman did indeed demonstrate pro-African personality views (as opposed to anti-African personality views that would have indicated negative effects as the result of colonization; see, however, Mwikamba, 2005). Thomas Parham (2002) has used two personality tests designed to focus more specifically on the concept of an African personality: the Racial Identity Attitude Scale (RIAS; which Parham helped develop) and the African Self-Consciousness Scale . The RIAS measures the nigrescence construct, whereas the African Self-Consciousness Scale is grounded in Afrocentric theory (closer to the concept of Negritude). However, Parham has come to the conclusion that both of these tests fall short of measuring the core elements of what might be a common African personality, particularly spiritness and the potential biogenetic nature of African people (Parham, 2002). Thus, if this is an appropriate field of study, there certainly needs to be further investigation to determine whether Western concepts of personality assessment apply to the essence of African personality.