By U. Georg. Hult International Business School. 2019.

The statistical methods that scientists use to test their research hypotheses are based on probability estimates protonix 20mg gastritis triggers. You will see statements in research reports indicating that the results were “statistically significant‖ or “not statistically significant order 40mg protonix with amex gastritis diet . These statements describe the statistical significance of the data that have been collected discount 40mg protonix with mastercard gastritis diet zx. Statistical significance refers to the confidence with which a scientist can conclude that data are not due to chance or random error order 20 mg protonix mastercard gastritis diet . When a researcher concludes that a result is statistically significant, he or she has determined that the observed data was very unlikely to have been caused by chance factors alone. Hence, there is likely a real relationship between or among the variables in the research design. Otherwise, the researcher concludes that the results were not statistically significant. Statistical conclusion validity refers to the extent to which we can be certain that the researcher has drawn accurate conclusions about the statistical significance of the research. Research will be invalid if the conclusions made about the research hypothesis are incorrect because statistical inferences about the collected data are in error. These errors can occur either because the scientist inappropriately infers that the data do support the research hypothesis when in fact they are due to chance, or when the researcher mistakenly fails to find support for the research hypothesis. Normally, we can assume that the researchers have done their best to ensure the statistical conclusion validity of a research design, but we must always keep in mind that Attributed to Charles Stangor Saylor. Internal validity refers to the extent to which we can trust the conclusions that have been drawn about the causal relationship between the independent and dependent variables (Campbell & [3] Stanley, 1963). Internal validity applies primarily to experimental research designs, in which the researcher hopes to conclude that the independent variable has caused the dependent variable. Internal validity is maximized when the research is free from the presence of confounding variables—variables other than the independent variable on which the participants in one experimental condition differ systematically from those in other conditions. Consider an experiment in which a researcher tested the hypothesis that drinking alcohol makes members of the opposite sex look more attractive. Participants older than 21 years of age were randomly assigned either to drink orange juice mixed with vodka or to drink orange juice alone. To eliminate the need for deception, the participants were told whether or not their drinks contained vodka. After enough time had passed for the alcohol to take effect, the participants were asked to rate the attractiveness of pictures of members of the opposite sex. The results of the experiment showed that, as predicted, the participants who drank the vodka rated the photos as significantly more attractive. If you think about this experiment for a minute, it may occur to you that although the researcher wanted to draw the conclusion that the alcohol caused the differences in perceived attractiveness, the expectation of having consumed alcohol is confounded with the presence of alcohol. That is, the people who drank alcohol also knew they drank alcohol, and those who did not drink alcohol knew they did not. It is possible that simply knowing that they were drinking alcohol, rather than the effect of the alcohol itself, may have caused the differences (see Figure 2. One solution to the problem of potential expectancy effects is to tell both groups that they are drinking orange juice and vodka but really give alcohol to only half of the participants (it is possible to do this because vodka has very little smell or taste). In the bottom panel alcohol consumed and alcohol expectancy are confounded, but in the top panel they are separate (independent). Confounding makes it impossible to be sure that the independent variable (rather than the confounding variable) caused the dependent variable. Another threat to internal validity can occur when the experimenter knows the research hypothesis and also knows which experimental condition the participants are in. The outcome is the potential for experimenter bias, a situation in which the experimenter subtly treats the research participants in the various experimental conditions differently, resulting in an invalid confirmation of the research hypothesis. In one study demonstrating experimenter bias, [4] Rosenthal and Fode (1963) sent twelve students to test a research hypothesis concerning maze learning in rats. Although it was not initially revealed to the students, they were actually the participants in an experiment. Six of the students were randomly told that the rats they would be testing had been bred to be highly intelligent, whereas the other six students were led to believe that the rats had been bred to be unintelligent. In reality there were no differences among the rats given to the two groups of students. The rats run by students who expected them to be intelligent showed significantly better maze learning than the rats run by students who expected them to be unintelligent. They evidently did something different when they tested the rats, perhaps subtly changing how they timed the maze running or how they treated the rats. To avoid experimenter bias, researchers frequently run experiments in which the researchers are blind to condition. This means that although the experimenters know the research hypotheses, they do not know which conditions the participants are assigned to. In a double-blind experiment, both the researcher and the research participants are blind to condition. For instance, in a double-blind trial of a drug, the researcher does not know whether the drug being given is the real drug or the Attributed to Charles Stangor Saylor. Double-blind experiments eliminate the potential for experimenter effects and at the same time eliminate participant expectancy effects. While internal validity refers to conclusions drawn about events that occurred within the experiment, external validity refers to the extent to which the results of a research design can be generalized beyond the specific way the original experiment was conducted. Generalization refers to the extent to which relationships among conceptual variables can be demonstrated in a wide variety of people and a wide variety of manipulated or measured variables. Psychologists who use college students as participants in their research may be concerned about generalization, wondering if their research will generalize to people who are not college students. And researchers who study the behaviors of employees in one company may wonder whether the same findings would translate to other companies.

As with mixed venous saturation cheap 20mg protonix overnight delivery gastritis diet , jugular bulb saturation (SjO2) indicates global cerebral oxygen delivery 20 mg protonix with visa gastritis diet , but cannot detect regional ischaemia Intensive care nursing 222 (Feldman & Robertson 1997) generic protonix 20 mg on-line gastritis diet wiki. Cerebral oxygen consumption is normally 35–40 per cent of available oxygen so that normal SjO2 is 60–65 per cent (March 1994); changes in SjO2 reflect changes in cerebral metabolic rate and cerebral blood flow generic 20 mg protonix with amex gastritis diet of augsburg. High SjO2 indicates ■ increased cerebral blood flow ■ reduced oxygen extraction ■ hyperventilation (respiratory alkalosis; leftward shunt of oxygen dissociation curve increasing affinity of haemoglobin for oxygen (Sikes & Segal 1994)) Levels below 54 per cent suggest cerebral hypoperfusion; below 40 per cent indicate global cerebral ischaemia (Dearden 1991). Approximately one-half of desaturation episodes are artificial, often due to low light intensity (Sikes & Segal 1994). The choice of catheters therefore depends on: ■ level of accuracy required ■ likely duration of monitoring ■ infection risk ■ equipment available. Intraventricular catheters with ventriculostomy (burr hole) provide the gold standard for intracranial pressure monitoring (Menon 1997). Bolts usually measure subdural pressure (Sutcliffe 1997) and, by not penetrating the ventricle, the risk of meningitis is reduced (Hickman et al. Advancing catheters into the non-dominant hemisphere reduces potential damage (Hanley 1997). Infection risks with intraventricular catheters remain low for 72 hours, then rise significantly (Sutcliffe 1997) but variably (0. Since infection means meningitis, the risk-benefit analysis should guide the choice and duration of intraventricular measurement. Infection risk is highest with fluid-filled systems (Price 1998) and so, as with other invasive equipment, maintaining closed circuits reduces infection (Hickman et al. Although both systolic and diastolic pressures are measured, normally mean pressure is the value recorded; all figures above refer to mean pressures. Fibre-optic catheters produce a pulse and trend waveform (Hall 1997); initially more reliable than bolts (Bruder et al. Neurological monitoring and intracranial hypertension 223 Fibre-optic systems do not introduce fluid, and so infection rates are low (Chitnavis & Polkey 1998). Glass fibres are fragile and break easily (Chitnavis & Polkey 1998)—sheaths can protect patients from harm. Fibre optics normally include a drainage channel, to relieve raised intracranial pressure. Once positioned, marking their location with permanent ink will help to identify any catheter migration (Hall 1997). Broadly similar to arterial waveforms, but with lower amplitude (Hall 1997), the waveform has three peaks (Hickey 1997a) (see Figure 22. Nursing intracranial pressure considerations Nursing responsibilities combine the technical roles of monitoring and regulating treatments with the holistic, person-centred care fundamental to nursing. Care of patients with raised intracranial pressure includes awareness of factors that might aggravate intracranial hypertension. While some common aspects are identified below, responses of different patients are individual so that nurses should always observe their patients to assess responses to each intervention (Odell 1996). Chudley (1994) recommends spacing each intervention by at least ten minutes, although this may need to be balanced against enabling adequate rest periods (see Chapter 3). The primary aim of care is to prevent aggravating intracranial hypertension; therefore, numbers and extent of interventions should normally be minimised. Rising (1993) found that only suctioning, turning and bed bathing caused transient increases in pressure; other interventions had no significant effects. Intrathoracic pressure Obstruction to venous drainage causes vascular engorgement, provoking oedema formation and intracranial hypertension. Historically, intracranial hypertension was treated by hyperventilation, hypocapnia causing vasoconstriction, so reducing intracranial hypertension. Hyperventilation may provoke secondary injury, and so should only be used where it will prove beneficial and can be closely monitored (Gerraci & Gerraci 1996). Respiratory alkalosis may compensate for metabolic acidosis, but it ■ reduces oxygen dissociation from haemoglobin (see Chapter 18); ■ causes vasoconstriction, reducing cerebral blood flow and perfusion pressure; ■ increases hydrostatic pressure, so causing oedema formation (Hinds & Watson 1996); ■ causes anaerobic metabolism (=metabolic acidosis); ■ lowers the seizure threshold (Winkelman 1995). Patients with intracranial hypertension are often sedated and ventilated for 5–7 days following injury (Odell 1996). If paralysing agents are used to prevent stimulation, nurses should ensure patients are adequately sedated beneath paralysis, both for humanitarian reasons and because stress from being paralysed but not sedated will aggravate hypertension (see Chapter 6). Weaning commences once intracranial pressure is stable and below 20 mmHg (Odell 1996). Suction Endotracheal suction, necessary to remove excessive secretions, will provoke intracranial transient hypertension (Brucia & Rudy 1996; Rising 1993). Bolus analgesia and sedation before suction can prevent dangerous hypertension (Hall 1997). As cerebral hypoxia is already likely to be present, patients with raised intracranial pressure should always be preoxygenated (100% oxygen) before suction. Dangers progressively increase with the number of passes, and so Chudley (1994) recommends at least ten seconds rest between each pass, with at least two minutes rest after suctioning. Although rarely used in practice, Chudley (1994) recommends giving intratracheal lignocaine beforehand. However, pressure area care interventions should be planned against risks from stimulation. Any positions impeding jugular venous drainage, such as head rotation (Hudak et al. Slight head elevation encourages venous drainage, so reducing intracranial hypertension.

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Bryce Wylde discount 20mg protonix mastercard gastritis diet brat, a colleague and well-known ho- meopathic doctor who discusses the principles of homeopathy and the top 25 conditions that can be helped with homeopathic medicine generic 40mg protonix free shipping gastritis diet . Conventional medical approaches are discussed and then I offer a natural prescription order protonix 20 mg mastercard gastritis diet butter, which in- cludes dietary strategies discount protonix 40 mg fast delivery gastritis diet 2012, lifestyle recommendations, and supplements. If you are coping with a health condition listed in this book, it is not my intention that you follow every recommendation I make. Instead, implement as many of the lifestyle and dietary strategies as possible and discuss my supplement recommendations with your health care provider. Under my “Top Recommended Supplements” section I list those that are supported by scientific research to offer benefits for the particular con- dition. Next, I list “Complementary Supplements”—those that offer some benefits or play a supportive role; these would be secondary considerations. Since many supplements have similar effects on the body, and there are potential interactions between drugs and supplements, it is recommended that you consult with your health care provider before taking a new product. Unlike many drugs, 4 | Introduction supplements may take weeks to months before the full effect is achieved, so patience is required. In addition to your primary care provider, you may want to look for addition- al health care providers that offer different perspectives, such as a naturopathic or homeopathic doctor, registered dietitian, massage therapist, acupuncturist, or chi- ropractor. When looking for alternative health care providers, make sure they are properly trained and always check references. You may also want to find a pharmacist in your area who, like myself, has a broad range of knowledge in natural medicine. Pharmacists are always available, without an appointment, to answer questions and discuss your concerns, especially about medications. Section Four contains the appendices—the supplementry charts, tables, and re- sources that are referred to throughout this book. That discovery set a course for my future that has taken me around the world from phar- macies and medical clinics, to lecture halls and conferences, through the writing of several health books, and finally to the publication of this reference guide. This latest book reflects many years of work and hundreds of hours of research, as well as my sincere desire to help Canadians achieve better health. Learn about the power of nutrition, exercise, supplements, stress management, and other lifestyle factors in the prevention of disease and take the necessary steps today. If you are currently struggling with a health problem, realize that there are options, and that a plan that incorporates a variety of healing modalities will most likely provide you with the best possible outcome. I hope I’ve provided you with a useful resource to achieve optimum health for you and your family. I wish you all the best as you create your own prescription for successful and healthy living! They are called “macro” because we need these nutrients in large quantities compared to the micro- nutrients (vitamins and minerals), which are needed in smaller quantities. In this section I will explain the various macronutrients, recommended intakes, and the best food sources. Macronutrients provide us with calories as follows: Carbohydrate: 4 calories per gram Protein: 4 calories per gram Fat: 9 calories per gram For example: If a food product contains 10 g of carbohydrate, 2 g of protein, and 1 g of fat per serv- ing, it would provide 10 × 4 = 40 calories from carbohydrate, 2 × 4 = 8 calories from protein, and 1 × 9 = 9 calories from fat for a total calorie count of 57 calories per serving. Food Sources Protein is found in animal products, nuts, legumes, and, to a lesser extent, in fruits and vegetables. When we eat protein the body breaks it down into amino acids, some of which are called essential because they must be provided by the food we eat. Choose free- range and organic wherever possible to reduce ingesting harmful hormones and chemicals. Plant proteins do not contain all the essential amino acids and are considered incomplete proteins. It is possible, though, to combine various plant proteins to get all the essential amino acids. For example, eating oats, lentils, and sunflower seeds either together or separately throughout the day provides all the essential amino acids. You could also combine whole-wheat pasta with white kidney beans or tofu with brown rice to get all the necessary amino acids. There are certain advantages of eating plant over animal proteins—they pro- vide fibre and phytochemicals (antioxidants), do not contain saturated fat, and may play a role in disease prevention. Soy protein, for example, has been shown to significantly lower cholesterol and triglyceride levels, and protect against bone loss. A number of studies have found lower risk of chronic disease in those who eat a plant-based diet. The Institute of Medicine recommends ranges for macronutrient intake that are associated with a reduced risk of chronic disease while providing adequate intake of essential nutrients. They suggest that adults get 45–65 percent of calories from carbohydrates, 20–35 percent from fat, and 10–35 percent from protein. Ranges for children are similar, except that infants and younger children need a slightly higher proportion of fat (25–40 percent). They also provide valuable nutrients (vitamins, minerals, and es- sential fatty acids) and fibre, which is important for intestinal health. Simple carbohydrates include naturally occurring sugars in milk and fruit, and refined sugars (granulated sugar). There is a major difference among these simple carbohydrates: fruits offer a range of nutrients and fibre, while refined sugars provide empty calories and lack Macronutrients | 9 nutritional value. The World Health Organization recommends reducing sugar intake to below 10 percent of total calories. Aside from candy and baked goods, sugar is also found in pop, condiments (ketchup, barbecue sauces), juices, ice cream, and other sweets. Today many of our starches are refined and processed, which strips the food of its fibre and nutrients. For example, white bread, pasta, and rice are much less nutritious, so choose the brown or whole-grain products.

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With more water outside the cell than inside buy protonix 20mg line gastritis zittern, the membrane would allow osmosis to continue past the breaking point purchase 20mg protonix with amex gastritis diet in pregnancy. It’s not just a coincidence that the nucleolus sits at the heart of the genetic powerhouse discount protonix 40 mg with visa chronic gastritis message boards. None of the other options are involved in cellular respiration or energy production l The most abundant protein in human cells is a order protonix 40 mg line gastritis and diarrhea. It makes sense that the protein making up much of the cytoskeleton is the most abundant because the cytoskeleton accounts for up to 50 percent of the cell’s volume. Part I: Building Blocks of the Body 36 When you think of a big protein-laden meal, you think of ribs. The correct answer can’t be the lysosome because that’s already a vesicle, and it can’t be the ribosome because you already know that handles proteins. In addi- tion, molecular concentration and agitation also can change cytoplasmic consistency. Fluid-like interior of the cell that may become a semisolid, or colloid L Lysosomes: c. Membranous sacs containing digestive enzymes M – Protein synthesis begins in the cell’s 38. Chapter 3 Divide and Conquer: Cellular Mitosis In This Chapter Following the steps of cell division Understanding the results of errors in mitosis ver had so many places to be that you wished you could just divide yourself in two? Cell division is how one “mother” cell becomes two identical twin “daughter” cells. Cell division takes place for several reasons: G r owth: Multicellular organisms, humans included, each start out as a single cell — the fertilized egg. That one cell divides (and divides and divides), eventually becoming an entire complex being. Injury repair: Uninjured cells in the areas surrounding damaged tissue divide to replace those that have been destroyed. Cell division occurs over the course of two processes: mitosis, which is when the chromo- somes within the cell’s nucleus duplicate to form two daughter nuclei; and cytokinesis, which takes place when the cell’s cytoplasm divides to surround the two newly formed nuclei. Although cell division breaks down into several stages, there are no pauses from one step to another. Cell division as a whole is called mitosis because most of the changes occur during that process. In this chapter, we review the cell cycle (as mitosis also is known), and you get plenty of practice figuring out what happens when and why. The Mitotic Process It may look like cells are living out their useful lives simply doing whatever specialized jobs they do best, but in truth mitosis is a continuous process. When the cell isn’t actively split- ting itself in two, it’s actively preparing to do so. Mitosis may look like a waiting game, but there’s plenty going on behind the scenes. Part I: Building Blocks of the Body 38 Waiting for action: Interphase Interphase is the period when the cell isn’t dividing. It begins when the new cells are done forming and ends when the cell prepares to divide. Although it’s also called a “resting stage,” there’s constant activity in the cell during interphase. Interphase is divided into subphases, each of which lasts anywhere from a few hours for those cells that divide frequently to days or years for those cells that divide less frequently (nerve cells, for example, can spend decades in interphase). Sorting out the parts: Prophase As the first active phase of mitosis, prophase is when structures in the cell’s nucleus begin to disappear, including the nuclear membrane (or envelope), nucleoplasm, and nucleoli. The two centrioles that have formed from the centrosome push apart to opposite ends of the nucleus. Using protein filaments, they form poles and a mitotic spindle between them as well as asters (or astral rays) which radiate from the poles into the cytoplasm. At the same time, the chromatin threads (or chromonemata) shorten and coil, forming visible chromosomes. The chromosomes divide into chro- matids that remain attached at an area called the centromere, which produces micro- tubules called kinetochore fibers. These interact with the spindle to assure that each daughter cell ultimately has a full set of chromosomes. The chromatids start to migrate toward the equatorial plane, an imaginary line between the poles. Dividing at the equator: Metaphase After the chromosomes are lined up and attached along the cell’s newly formed equa- tor, metaphase officially debuts. The chromatids line up exactly along the center line of the cell (or the equatorial plane), attaching to the mitotic spindle by the centromere. Packing up to move out: Anaphase In anaphase, the centromeres split, separating the duplicate chromatids and forming two chromosomes. The spindles attached to the divided centromeres shorten, pulling the chromosomes toward the opposite poles. In late anaphase, as the chromosomes approach the poles, a slight furrow develops in the cytoplasm, showing where cytokinesis will eventually take place. Chapter 3: Divide and Conquer: Cellular Mitosis 39 Pinching off: Telophase Telophase occurs as the cell nears the end of division.

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