Sampling Probability Essay Example for Free

Sampling Probability Essay Probability And Non Probability Sampling Cultural Studies Essay A probability sampling method is any method of sampling that utilizes some form of random selection. In order to have a random selection method, you must set up some process or procedure that assures that the different units in your population have equal probabilities of being chosen. Humans have long practiced various forms of random selection, such as picking a name out of a hat, or choosing the short straw. These days, we tend to use computers as the mechanism for generating random numbers as the basis for random selection. Probability sampling methods are those in which every item in the universe has a known chance, or probability of being chosen for sample. This implies that the selection of the sample items is independent of the person making the study that is the sampling operation is controlled so objectively that the items will be chosen strictly at random. Types of probability sampling Simple Random Sampling: The simplest form of random sampling is called simple random sampling. Neither of these mechanical procedures is very feasible and, with the development of inexpensive computers there is a much easier way. Simple random sampling is simple to accomplish and is easy to explain to others. Because simple random sampling is a fair way to select a sample, it is reasonable to generalize the results from the sample back to the population. Simple random sampling is not the most statistically efficient method of sampling and you may, just because of the luck of the draw, not get good representation of subgroups in a population. To deal with these issues, we have to turn to other sampling methods. Systematic Sampling: Stratified Random Sampling, also sometimes called proportional or quota random sampling, involves dividing your population into homogeneous subgroups and then taking a simple random sample in each subgroup. There are several major reasons why you might pref er stratified sampling over simple random sampling. First, it assures that you will be able to represent not only the overall population, but also key subgroups of the population, especially small minority groups. If you want to be able to talk about subgroups, this may be the only way to effectively assure youll be able to. If the subgroup is extremely small, you can use different sampling fractions within the different strata to randomly over-sample the small group. When we  use the same sampling fraction within strata we are conducting proportionate stratified random sampling. When we use different sampling fractions in the strata, we call this disproportionate stratified random sampling. Second, stratified random sampling will generally have more statistical precision than simple random sampling. This will only be true if the strata or groups are homogeneous. If they are, we expect that the variability within-groups are lower than the variability for the population as a whole. Stratified sampling capitalizes on that fact. Strati fied Sampling: For this to work it is essential that the units in the population are randomly ordered, at least with respect to the characteristics you are measuring. For one thing, it is fairly easy to do. You only have to select a single random number to start things off. It may also be more precise than simple random sampling. Finally, in some situations there is simply no easier way to do random sampling. For instance, I once had to do a study that involved sampling from all the books in a library. Once selected, I would have to go to the shelf, locate the book, and record when it last circulated. I knew that I had a fairly good sampling frame in the form of the shelf list (which is a card catalogue where the entries are arranged in the order they occur on the shelf). To do a simple random sample, I could have estimated the total number of books and generated random numbers to draw the sample. Cluster Sampling: The problem with random sampling methods when we have to sample a population thats disbursed across a wide geographic region is that you will have to cover a lot of ground geographically in order to get to each of the units you sampled. Imagine taking a simple random sample of all the residents of New York State in order to conduct personal interviews. By the luck of the draw you will wind up with respondents who come from all over the state. Your interviewers are going to have a lot of travelling to do. It is for precisely this problem that cluster or area random sampling was invented. In cluster sampling, we follow these steps: divide population into clusters (usually along geographic boundaries), randomly sample clusters, and measure all units within sampled clusters. Multi Stage Sampling: The four methods weve covered so far simple, stratified, and systematic and cluster are the simplest random sampling strategies. In most real applied social research, we would use sampling methods that are considerably more complex than these simple variations. The most important principle here is  that we can combine the simple methods described earlier in a variety of useful ways that help us address our sampling needs in the most efficient and effective manner possible. When we combine sampling methods, we call this multi-stage sampling. Non probability Sampling Non probability sampling methods are those, which do not provide every item in the universe with a known chance of being included in the sample. The selection process is to some extent The difference between non probability and probability sampling is that non probability sampling does not involve random selection and probability sampling does. Does that mean that non probability samples arent representative of the population? Not necessarily. But it does mean that non probability samples cannot depend upon the rationale of probability theory. At least with a probabilistic sample, we know the odds or probability that we have represented the population well. We are able to estimate confidence intervals for the statistic. With non probability samples, we may or may not represent the population well, and it will often be hard for us to know how well weve done so. In general, researchers prefer probabilistic or random sampling methods over non probabilistic ones, and consider them to be more accurate and rigorous. However, in applied social research there may be circumstances where it is not feasible, practical or theoretically sensible to do random sampling. Here, we consider a wide range of non probabilistic alternatives. We can divide non probability sampling methods into two broad types: accidental or purposive. Most sampling methods are purposive in nature because we usually approach the sampling problem with a specific plan in mind. The most important distinctions among these types of sampling methods are the ones between the different types of purposive sampling approaches. Types of non probability sampling Accidental, Haphazard or Convenience Sampling: One of the most common methods of sampling goes under the various titles listed here. I would include in this category the traditional man on the street (of course, now its probably the person on the street) interviews conducted frequently by television news programs to get a quick (although non representative) reading of public opinion. I would also argue that the typical use of  college students in much psychological research is primarily a matter of convenience. In clinical practice, we might use clients who are available to us as our sample. In many research contexts, we sample simply by asking for volunteers. Clearly, the problem with all of these types of samples is that we have no evidence that they are representative of the populations were interested in generalizing to and in many cases we would clearly suspect that they are not. Purposive Sampling: In purposive sampling, we sample with a purpose in mind. We usually would have one or more specific predefined groups we are seeking. They size up the people passing by and anyone who looks to be in that category they stop to ask if they will participate. One of the first things theyre likely to do is verify that the respondent does in fact meet the criteria for being in the sample. Purposive sampling can be very useful for situations where you need to reach a targeted sample quickly and where sampling for proportionality is not the primary concern. With a purposive sample, you are likely to get the opinions of your target population, but you are also likely to overweight subgroups in your population that are more readily accessible. For each type of sampling give the advantages and disadvantages. Advantages and Disadvantages of Probability sampling Simple Random Sampling: Advantages: It is easy to implement It requires a listing of population element. Since selection of its items in the sample depends on change there is no possibility of personal bias affecting the result. As compared to judgment sampling a random sample represents the universe in a better way. As the size of the sample increases, it becomes increasingly representative of the population. The analyst can easily assess the accuracy of the estimates because sampling errors follows the principle of chance. The theory of random sampling is further developed than that of any type of sampling, which enables the researcher to provide the most reliable information at least cost. Disadvantages The use of simple random sampling necessitates a completely catalogued  universe from which to draw the sample. That is it uses large sample size. The size of the sample requires ensuring the statistical reliability is usually under random sampling rather than stratified. From the point of view of field survey it has been claimed that the cases selected by random sampling tend to be too widely dispersed geographically and that the time and the cost of collecting data becomes very large. It produces large errors. Random sampling may produce the most non random looking results. Systematic Sampling Advantages It is simple to design and convenient to adopt. It is easier to use than simple random sampling It is easy to determine sampling distribution Less expensive than random sampling. The time and work involved in sampling by this method are relatively less. The result obtained are found to be generally satisfactory provided care is taken to see that there are no periodic features associated with the sampling intervals. If the population are sufficiently large, systematic sampling can often be expected to yield results similar to those obtained by proportional stratified sampling. Disadvantages Using intervals may squeeze the sample and the result. If the population list has a monotonic trend a bias estimate will result from the starting point. The main issue is that it becomes fewer representatives if the analyst is dealing with populations having hidden periodic that is not all the elements are known. Stratified Sampling Advantages The researcher control the sample size in each group Increase efficiency It is more representative as population is first divided into various strata and then sample is drawn from each stratum. Thus there is little chance that any essential group of the population is being completely excluded. There is greater accuracy as each stratum will consist of uniform or homogenous items. Disadvantages Provide data to represent and analyse sub groups. Increase error in reason if sub group are selected at different rate. It is expensive because it is widely distributed geographically and the sample costs per observation are high. If the sample is not homogeneous the result may not be reliable. It requires assistance of skilled sampling supervisors. Cluster Sampling Advantages It provides a unilateral estimate of population. It is more efficient It is easy to do without population unit. It enables each sub division of the population to be used at various stages and permits the fieldwork to be more concentrated. It is valuable in surveys of underdeveloped areas. Can be cheaper than other methods e.g. fewer travel expenses, administration costs Disadvantages It is more error prone. Higher sampling error, which can be expressed in the so-called design effect, the ratio between the number of subjects in the cluster study and the number of subjects in an equally reliable, randomly sampled unclustered study. Multi Stage Sampling Advantages The main purpose of the creation and present-day use of multi-stage sampling is ti avoid the problems of randomly sampling from a population that is larger than the researchers resources can handle. Multi-stage sampling gives researchers with limited funds and time a method to sample from such populations. This sampling procedure in essence is a way to reduce the population by cutting it up into smaller groups, which then can be the subject of random sampling. As long as the groups have low between-group variance, this form of sampling is a legitimate way to simplify the population. The multi-stage form of sampling is flexible in many senses. First, it allows researchers to employ random sampling or cluster sampling after the determination of groups. Second, researchers can employ  multi-stage sampling indefinitely to break down groups and subgroups into smaller groups until the researcher reaches the desired type or size of groups. Last, there are no restrictions on how researcher s divide the population into groups/ This allows a large number of possibilities for methods of convenience, the maximization or minimization of variance or interpretability. Disadvantages The flexibility of multi-stage sampling is a double-edged sword. Because of the lack of restrictions on the decision processes involved in choosing groups, multi-stage sampling has a level of subjectivity. Thus, there will always be questions as to whether the chosen groups were optimal. Researchers must find a way to justify their choices when presenting the studys findings. Due to the fact that multi-stage sampling cuts out portions of the population from the study, the studys findings can never be 100% representative of the population. Even though the theory of multi-stage sampling is to focus on the within-group variance and de-emphasize the between-group variance (which should be minimized), there is no way to know if the demographics cut from the study could have provided any useful information to the researchers. (http://www.ehow.com/info_8544049_advantages-disadvantages-multistage-sampling.html#ixzz27Sqmq8C8) Advantages and Disadvantages of Non probability sampling (Non Rando m Sampling) Convenience Sampling Advantages Convenience samples are cheap. Convenience samples can be used to intervene to satisfy dissatisfied customers. A key, often forgotten aspect of probability sampling is its dependence on external selection: inviting and then repeatedly reminding people to take a survey, which helps ensure representativeness. Putting a survey postcard with every bill presented at a restaurant is a convenience sample, since there is no follow-up and encouragement to take the survey: no true external selection. And in such cases dissatisfied customers are often more likely to complete such surveys – the survey does provide an opportunity to hear from such customers and ask them for contact information in order to take action to improve their satisfaction. Convenience samples  can provide rich qualitative information. When illustrative quotes are important, surveys to convenience samples can be a great source of rich verbatim comments on specific topics. The survey can also provide detailed demographic profiles to shed further light on the comments. Convenience samples may provide accurate correlations. Some argue that correlation research is accurate enough with convenience samples, since the study is not of proportions of the target audience but of the relationship between variables. Disadvantages Convenience samples do not produce representative results. If you need to extrapolate to the target population, convenience samples aren’t going to get you there. The natural tendency is to extrapolate from convenience samples. The tendency when using convenience samples is to treat the results as representative, even though they are not. Many people do not understand the theoretical underpinnings of probability sampling and treat any survey results as accurate representations of the target audience. While mainstream media outlets often will not publicize the results of surveys that used convenience samples, small media organizations often will, without describing the methodology as a convenience sample. The results of convenience samples are hard to replicate. If you analyze the results of a convenience survey by list source, you will often find dramatic differences in the answers from the different lists, often in ways that confound easy explanation Quota Sampling Quota sampling is particularly useful when you are unable to obtain a probability sample, but you are still trying to create a sample that is as representative as possible of the population being studied. In this respect, it is the non-probability based equivalent of the stratified random sample. Unlike probability sampling techniques, especially stratified random sampling, quota sampling is much quicker and easier to carry out because it does not require a sampling frame and the strict use of random sampling techniques (i.e. probability sampling techniques). This makes quota sampling popular in undergraduate and master’s level dissertations where there is a need to divide the population being studied into strata (groups). The quota sample improves the representation of particular strata (groups) within the  population, as well as ensuring that these strata are not over-represented. For example, it would ensure that we have sufficient male students taking part in the research (60% of our sample size of 100; hence, 60 male students). It would also make sure we did not have more than 60 male students, which would result in an over-representation of male students in our research. The use of a quota sample, which leads to the stratification of a sample (e.g. male and female students), allows us to more easily compare these groups (strata). Disadvantages of quota sampling In quota sampling, the sample has not been chosen using random selection, which makes it impossible to determine the possible sampling error. Indeed, it is possible that the selection of units to be included in the sample will be based on ease of access and cost considerations, resulting in sampling bias. It also means that it is not possible to make generalisations (i.e. statistical inferences) from the sample to the population. This can lead to problems of external validity. Also, with quota sampling it must be possible to clearly divide the population into strata; that is, each unit from the population must only belong to one stratum. In our example, this would be fairly simple, since our strata are male and female students. Clearly, a student could only be classified as either male or female. No student could fit into both categories (ignoring transgender issues). Furthermore, imagine extending the sampling requirements such that we were also interested in how career goals changed depending on whether a student was an undergraduate or postgraduate. Since the strata must be mutually exclusive, this means that we would need to sample four strata from the population: undergraduate males, undergraduate females, postgraduate males, and postgraduate females. This will increase overall sample size required for the research, which can increase costs and time to carry out the research Purposive or Judgemental Sampling The advantages of Judgment sampling are: Lower cost of sampling Lesser time involved in the process A select number of people who are known to be related to the topic are part of the study which means that there are lesser chances of having people who  will distort the data Good method for pretesting instruments like questionnaires. Some disadvantages are: It can be subject to experimenter’s bias and stereotypes that may distort the results. The group selected may not represent all the population It might not be possible to accurately identify the sample using this method in case the population is very large.

Balancing Productivity and Quality Patient Care

Balancing Productivity and Quality Patient Care Balancing Productivity and Quality Patient Care Abstract The purpose of this examination is to identify challenges balancing productivity and quality patient care as it stands from a supervisory position. Today’s supervisors must not only focus on their staff and patients, but also on the organizational business aspects such as increasing productivity and quality patient care. Supervisors are getting sandwiched between balancing productivity and quality care. In this somewhat daunting quandary the supervisors must strive to find ways to accomplish both missions. As I will propose this will require communication changes in organizational health care systems and a paradigm shift in current ideologies in the health care industry. Let’s start off in my own backyard so to speak, my organization is a Nursing and Rehabilitation hospital. The Mission statement is, â€Å"Come Here, Get Well, and Go Home†. This is a 213 bed facility. There are approximately 135 employees throughout the organization working on any given day. The organization specializes in sub-acute care, long-term care and has a rehabilitation unit. Also the organization has physical therapy, occupational therapy and speech therapy components to support patient’s recovery. All of these people in organization eventually may have some contact with a new patient at different times in the recovery process. It is obvious from a macro-perspective it would be difficult to realize any improvements in productivity or patient care without solid supervisory skills and knowledge. Nursing is my focus and professional occupation in which I will narrow the field to nursing for this examination. As a nursing supervisor one has to continually be knowledgeable to accomplish both goals of productivity and quality patient care. Their responsibilities include planning, organizing and overseeing staff. Nurse supervisors provided leadership two staffs under their charge. The nurse supervisor implements and interprets organizational policies and procedures maintaining nursing standards and regulations. They also continually evaluate patient care and ensuring their satisfaction. A nursing supervisor skills also include budgeting, prioritizing duties and delegating responsibilities. Some of the obstacles that impede the ability of nursing supervisors out of their control is rising healthcare expenditures have motivated spending reforms such as Medicares payment system. While such initiatives aim to limit wasteful healthcare expenses, they may inadvertently result in lower-quality care: providers may face an incentive to reduce the quality of their treatments to minimize costs and increase patient loads. (McDevitt, 2013) Unfortunately this is not the only pressure in which health care organizations have to do more with less. Supplies, operating costs, state and national legislation has placed a huge strain on the healthcare system at large. In the past nursing productivity has been the defined as the ratio of patient care per hour, per patient to salary and benefit costs paid out to staff by the organization. (Kohr, 2012) In the current economy this does not take into consideration the level of expertise in which nurses must process information to accomplish the goals of increased productivity and patient care. After all of that is said: Nursing productivity models of any kind should take into account patients’ needs, nursing competencies, the availability of material resources, and services provided. Nursing workload is a direct reflection of these variables and affects the delivery of patient care, patient safety, as well as satisfaction of nurses and of patients and their family members. Many investigators have linked nursing staff indicators and nurse staffing with patients’ outcomes (Kohr, 2012) The problems of balancing productivity with quality patients care are reducing costs and employee hours for the sake of protecting the bottom line is that really â€Å"protecting the patient?.† Yet that statement has clearly infiltrated and grayed the area between professional ethical, moral boundaries. In attempts at optimizing for efficiency are we as supervisors ultimately must manage both dichotomies. Managing these dichotomies is seemingly overwhelming at first glance. This is what I mean by the proverbial sandwich effect, the danger here is being so overwhelmed that you are paralyzed into doing nothing. I contend that productivity and quality patient care are not at odds with one another: they are both vital to the success of any healthcare organization. The essence of productivity vs. quality patient care dilemma is this: Productivity is visible, continuous, readily-understood and directly measured: a daily metric. On the other hand, quality patient care is invisible, boring, discontinuous, indirect, and its success is measured by the absence of negative outcomes. (Appel, 2012) Now that’s somewhat of a quandary. Almost in the same breath organizations are willing to state quality patient care is our core principle. The problem, however, is turning that vision into action: it is in the daily operations (Appel, 2012) and responsibility functions of the nurse supervisor, this is where the rubber meets the road. Nurse supervisors are critical to the surveillance and coordination that reduce such adverse outcomes. Much work remains to be done in evaluating the impact of nursing care on positive quality care indicators, such as appropriate self-care and other measures of improved health status. (Mitchell, 2008) Nurse supervisors must instill in the people that they manage to continually gather information that can be correlated into data to finding that balance between productivity and quality patient care. Whether it be quantitative or qualitative data all must be brought together to facilitate to make informed decision for possible change. Harnessing this information could unlock knowledge that may elicit innovations striking that balance between productivity and quality patient care. Leave no stone unturned, is the mantra of nurse supervisors in today’s tough economic and social times. How do we start? Communication, communication, communication is essential to establish any opportunity to balance a seemingly diametrically opposed processes. They can be integrated (productivity and quality patient care) to provide success for the organization and the patient. Tighter reins of communication and functions must be streamlined for optimal performance. Nurse supervisors can trigger a needs analysis of the situation informing the employees and organization that there is a performance gap between productivity and quality patient care. This brings in the team concept of the organization as a whole (everyone’s job) needs to be the spearhead, focal point for systematic change and concern with both issues of productivity and quality patient care. A decision-making structures is needed, a paradigm shift. What is a paradigm shift? Stephen Covey suggests that a paradigm shift is what we might call the AHA ! experience when someone finally sees the composite picture in another way or finally sees the light. (Covey, 2004) The health care industry has been moving â€Å"paradigm shift toward placing more value on quality and outcomes. This affect has changed in the way health care organizations do business. Higher quality can be the solution, said Dr. Michael Ogden, chief clinical integration officer with Cornerstone Health Care during the discussion at High Point University. In health care specifically, higher quality could actually lead to lower costs. (Covington, 2014) As a nurse supervisor myself this sounds good but how do we get there? Some employers and health plans are pushing for greater price transparency. They argue that if consumers realized that they could receive high-quality services from lower-cost providers, they would seek them out. This, in turn, could encourage competition among providers based on the value of care not just on reputation and market share. (Unknown, 2012) Another aspect would be to empower the patients to be active participants making decisions about their own care. Empowerment of the patient also means to include them as a part of the health care team which may stimulate opportunities and innovation. As a nurse supervisors some of these ideas are not new, I however assert that nurse supervisors must educate themselves to perform their managerial duties at high levels, not only will the organization benefit, but so too will the patients. Nurse supervisors will need considerable intestinal fortitude to sustain balancing productivity and quality patient care. A nurse supervisor of the future will have to be multi-dimensional with traits like leadership and persuasion skills. Nurse supervisors must show empathy, creating trust with coworkers and patients. They must also have analysis skills, to be able to make fact-based decisions. Last but not least, a nurse supervisor must have performance management and coaching skills to follow through on goals and objectives. Finally, I concludes this examination by making a statement that balancing productivity and quality patient care will always be challenging. References Appel, M. (2012, April 20). KevinMD. Retrieved from The problem of mixing productivity with patient safety: http://www.kevinmd.com/blog/2012/04/problem-mixing-productivity-patient-safety.html Covey, S. R. (2004). The 7 Habits of Highly Effective People: Powerful Lessons in Personal Change. New York : Free Press a division of Simon and Schuster. Covington, O. (2014, March 21st). Health care providers tout paradigm shift as path to reining in costs. Triad Business Journal. Kohr, L. M. (2012, November Volume 21, No 6). American Journal of Critical Care. Retrieved from Building a Nurse and Productivity Measure Based on this Energy Model: http://www.aacn.org/wd/Cetests/media/A1221063.pdf McDevitt, P. L. (2013, February). Productivity and Quality in Health Care:Evidence from the Dialysis Industry. Retrieved from http://www.econ.psu.edu/~plg15/gm_dialysis_Feb2013.pdf. Mitchell, P. H. (2008). Patient Safety and Quality: An Evidence-Based Handbook for Nurses. Rockville, Md: Agency for Health Care Research and Quality. Unknown. (2012, April/May). The Commonwealth fund. Retrieved from Quality Matters: http://www.commonwealthfund.org/Newsletters/Quality-Matters/2012/April-May/In-Focus.aspx

Developmental Profile :: Teaching Education

Developmental Profile Developmental Profile for Adolescents Physical Characteristics 1. Concerning boys in this period, in general the penis and scrotum get much larger, hair appears in the axillae and in the pubic area, the voice begins to deepen, and the spurt of height and weight begins. This period, for girls, is a time of rounding out and completing major changes in the secondary sex characteristics. For example, most have begun menstruation and the weight and height gains have slowed down (Babcock, 1967). 2. Puberty is set into action by the increase of the hormone testosterone in males and estrogen in females (Rathus, et al., 1986). 3. The primary sex characteristics enlarge and mature: in males--the testes, prostate gland, penis and seminal vesicles, in females--the ovaries, uterus and vagina (Papalia, et al., 1998). 4. Acne develops in some adolescents, due to the change in hormones, and can last well into adulthood (Edelman, et al., 1994). 5. Toward the end of puberty, menarche in girls and ejaculation in boys signals reproductive potential. Puberty that is early or late can be stressful, although the specifics depend on gender, personality, and culture (Berger, 1998). Intellectual Characteristics 1. According to Piaget, adolescents enter the highest level of cognitive development--formal operations--when they develop the capacity for abstract thought (Papalia, et al., 1998). 2. An adolescent may be adult in his ability to reason and vote, but he's more childish in his attitude toward sex and marriage (Babcock, 1967). 3. Adolescent egocentrism, along with feelings of uniqueness and invincibility, can cloud judgment, as well as make them extraordinarily self-absorbed (Berger, 1998). 4. The specific intellectual advancement of each teenager depends greatly on education. Each culture and each school emphasizes different subjects, values, and modes of thinking, a variation which makes some adolescents much more sophisticated in their thoughts and behavior than others (Berger, 1998). 5. Erickson's Theory of identity vs. identity confusion emerges. This is involves the adolescent determining his/her own sense of self or experience confusion about roles (Edelman, et al., 1994). Socio-Emotional (Behavioral) 1. Some young adolescent girls, more so than boys, are dealing with eating disorders such as Bulimia and Anorexia (Papalia, et al., 1998). 2. Sexual activity rises for a variety of reasons, such as, seeking affection, peer pressure, as a symbol of maturity, spontaneous experimentation, to feel close, and because it feels good (Edelman, et al., 1994). 3. Given the restrictions placed on adolescents, their yearning for independence, and a sex drive heightened by high levels of sex hormones, it is not surprising that many adolescents report frequent conflict with their families (Rathus, et al.

The Causitive Agent of Rocky Mountain Spotted Fever Essay -- Biology M

The Causitive Agent of Rocky Mountain Spotted Fever The Bacteria Rickettsia rickettsii is the small, aerobic gram-negative bacterium that is the cause Rocky Mountain spotted fever in humans (and other vertebrates). They are obligate, intracellular bacteria that range in size form 0.2x0.5  µm to 0.3x2.0 µm. Rickettsia belong to the phylum alpha-protobacteria, which are capable of growing in low levels of nutrients, and have a long generation time relative to other gram negative bacteria such as Escherichia coli. In humans rickettsiae preferentially reside in the nucleus or cytoplasm of cells lining small to medium size blood vessels. Rickettsia enter host cell by inducing phagocytosis, then immediately escape the phagosome to grow and reproduce within the cytoplasm (or nucleus)of the host cell. The host cell will normally lyse eventually, causing the release of new organisms. The host cell is also harmed by the toxic effect of the cell wall. (CDC) Van Kirk et al have done studies showing that actin-based motility (ABM) is a mechanism for intercellular spread. R. rickettsii is the only Rickettsia species that utilizes ABM. Findings suggest that ABM is a major factor in causing infection; after a host cell becomes infected the polymerization of the actin of the host cell forms a filamentous actin comet tail. The actin tail aids the pathogen in moving through the cytosol and into membrane protrusions of the host cell, where it can be engulfed by neighboring cells and can initiate a new infectious cycle. The Vector Rocky Mountain spotted fever (RMSF) is classified as a zoonosis (diseases of animals that can be transmitted to humans), and requires a vector for transmission. The vectors (and reservoirs) for RMSF are tic... ...G. Marshall, Anita M Kelsey, MD. â€Å"What’s Your Diagnosis?† Consultant August 1996:1729-1735 Niebylski, Mark L., Mort G. Peacock, and Tom G. Schwan. â€Å"Lethal Effect of Rickettsia rickettsii on Its Tick Vector (Dermacentor andersoni)† Applied and Environmental Microbiology Feb 1999: p 773-338. Rahman, M. Sayeedur, Jason A. Simser, Kein R. Macaluso, and Abdu F. Azad. â€Å"Molecular and Funcional Analysis of the lepB Gene, Encoding a Type I Signal Peptidase from Rickettsia rickettsii and Rickettsia typhi.† Journal of Bacteriology August 2003 (2003 American Society for Microbiology):4578-4584. Van kirk, Levi S., Stanley F. Hayes, and Robert A. Heinzen. â€Å"Ultrastructure of Rickettsia rickettsii Actin Tails and Localization of Cytoskeletal Proteins.† Infection and Immunity (August 2000). Abstract. 16 September 2004. .

Nelson Mandela Essay -- Nelson Mandela Essays

Activist, lawyer, father, prisoner, survivor, president, the face of equality. Nelson Mandela has an inspiring story of fighting Apartheid forces and surviving a long prison sentence all in the name of freedom and equal rights. Through Nelson Mandela’s constant fight for freedom of the African people from white apartheid forces, he was dominated by the corrupt government. After uprising numerous riots against apartheid forces, Mandela was sent to jail for twenty-seven years revealing the cruelty that humans can possess. With the strong will power and complete support of the African people, Mandela survived his prison sentence and became the first democratically elected president of South Africa exposing the strength in human nature by showing that humans can persevere through tough times. Mandela left a profound impact on the African people by saving them from corrupt Apartheid rule and bringing a democratic government. Thus teaching the world that in an event where a body of people is suppressed, they will inevitably rebel by any means necessary to gain their freedom. Nelson Mandela’s life can be seen as a double climax: where he survived events directly related to the Apartheid’s cruel/unjust actions along with enduring medical ailments later on in his life. In a four year span, from 1960 to 1964, Mandela had to find strength and will power to persevere through a rollercoaster of events. Mandela’s affiliation in the African National Congress allowed him to organize supporters and protest against the inequality of whites and blacks in Africa, and bring attention to the abuse blacks have been forced to endure for far too long. The constant back and forth commotion between the apartheid and the freedom protestors caused a snowba... ...t a Middle East country? Would similar things/punishments occur? Works Cited de Zayas, Alfred. "Nelson Mandela." Encyclopedia of Genocide and Crimes Against Humanity. Ed. Dinah L. Shelton. Detroit: Macmillan Reference USA, 2005. Gale Biography In Context. Web. 11 Mar. 2012. Humanitarians and Reformers. New York: Macmillan Library Reference USA, 1999. Print. Keller, Bill. Tree Shaker: The Story of Nelson Mandela. Boston: Kingfisher, 2008. Print. Mandela, Nelson, and Nelson Mandela. Mandela: An Illustrated Autobiography. Boston: Little, Brown, 1996. Print. McKenna, Amy. The 100 Most Influential World Leaders of All Time. New York, NY: Britannica Educational Pub. in Association with Rosen Educational Services, 2010. Print. "Nelson Rolihlahla Mandela." Encyclopedia of World Biography. Detroit: Gale, 1998. Gale Biography In Context. Web. 11 Mar. 2012.

Gaming Addiction study Essay

According to Daria J Kuss in the 2000s, online games became popular, while studies of Internet gaming addiction emerged, outlining the negative consequences of excessive gaming, its prevalence, and associated risk factors. Internet gaming is a booming market. In 2012, more than one billion individuals played computer games, which fuelled the 8% growth of the computer gaming industry in the same year. A recent report by the market research company Niko Partners has estimated the People’s Republic of China’s online gaming market at $12 billion in 2013. In her research she stated that Internet gaming addiction has increased both in quantity as well as in quality. Research on gaming addiction dates back to 1983, when the first report emerged suggesting that video gaming addiction is a problem for students. Shortly thereafter, the first empirical study on gaming addiction was published by Shotton, based on self-reports of young male players who claimed they were â€Å"hooke d† on their games. The early studies suffered from a lack of standardized psychometric instruments used for assessing gaming addiction. Massively Multiplayer Online Role-Playing Games (MMORPGs), on the other hand, appear of particular interest to players because they offer a variety of incentives for play relative to other game genres. Of all online gamers, 46% play MMORPGs,3 confirming their position as the most popular online games. MMORPGs are game universes inhabited by thousands of players at the same time (massively multiplayer) with no spatial or temporal boundaries because they are played online, and they allow players to adopt various virtual personas in their avatars (role playing). In South-East Asian countries, the negative impacts of Internet gaming  addiction have led governments and health care providers to take the problem seriously and to develop a series of initiatives to curb and alleviate the problem. In South Korea, Internet gaming addiction is viewed as a significant concern for public health, and up to 24% of children who have been diagnosed with Internet addiction are hospitalized. In Japan, the government has recognized the problem following a study by the Ministry of Education, which has led to the development of â€Å"fasting camps† where individuals suffering from Internet and gaming addiction are helped by being cut off from technology completely. It has been stated that the higher the Internet penetration and social acceptance of gaming, the higher the prevalence of gaming problems, partially explaining the higher prevalence rates reported in South-East Asian countries. In addition to this, there is good reason to think that the lower acceptance of excessive gaming in a culture, the more distress (not less) gamers experience in engaging in the activity, potentially fuelling problem perception. Therefore, a lack of acceptance of excessive gaming and thus stigmatization of the behavior might contribute to higher rates of addiction and problematic play in some way. Following growing concern, specialized treatment centers and programs have been established in Europe (including the outpatient clinic for behavioral addictions in Mainz, Germany, and the Capio Nightingale Hospital in London, UK) and the US (including the inpatient centers RESTART Internet Addiction Recovery Program in Seattle and the recently opened digital detoxification and recovery center in Pennsylvania), reflecting the growing need for professional help. Internet gaming addiction is a behavioral problem that has been classified and explained in numerous ways. According to Griffiths,13 biopsychosocial processes lead to the development of addictions, such as Internet gaming addiction, which include the following components. First, the behavior is salient (the individual is preoccupied with gaming). Second, the individual uses the behavior in order to modify their mood (ie, gaming is used to escape reality or create the feeling of euphoria). Third, tolerance develops (the individual needs increasingly more time to feel the same effect). Fourth, withdrawal symptoms occur upon discontinuation of the behavior (the individual feels anxious, depressed, and irritable if they are prevented  from playing). Fifth, interpersonal and intra-personal conflict develops as a consequence of the behavior (the individual has problems with their relationship, job, and hobbies, and lack of success in abstinence). Finally, upon discontinuation of the beha vior, the individual experiences relapse (they reinitiate gaming). Although the core criteria appear to be established, the etiology of Internet gaming addiction has yet to be studied in detail. Research15 indicates that a number of risk factors are associated with Internet gaming addiction. These risk factors include certain personality traits, gaming motivations, and structural game characteristics. The personality traits most commonly associated with Internet addiction include neuroticism,37,50 aggression and hostility,43,50–52 and sensation-seeking.43,50 Factors that appear to protect frequent online gamers from developing problems with their gaming were found to be conscientiousness and extraversion,53 suggesting that for different individuals the same behavior can have different psychological repercussions. In addition to this, the following gaming motivations were found to be most commonly associated with gaming addiction: coping with daily stressors and escapism, online relationships, and mastery, control, recognition, completion, excitement, and challenge. This indicates that the reasons for game play may be an important indicator of potential risk for Internet gaming addiction. Specifically, in comparison with non-MMORPG players, MMORPG players preferred their online friends over their real-life friends. Similarly, significantly more dependent gamers were found to prefer spending time with their online friends than their offline friends relative to nondependent gamers and felt their social needs were met better online than offline. Moreover, while online games provide nonaddicted players with satisfaction, addicted players play to avoid dissatisfaction, which can be an indication of withdrawal symptoms they want to overcome by engaging in gaming compulsively. The motivational differences to play games between dependent and nondependent as well as MMORPG and other gamers appear to be useful clinical information because these motivations can be specifically targeted in treatment sessions. For instance, elements of exposure therapy  may be used for the socially fearful in order to decrease discomfort and reintroduce clients to real-life social environments. Also, alternative pastime activities that are perceived as satisfying can be encouraged specifically in group therapy sessions. Encouraging engagement in group sports might satisfy both the need to engage in competitive and satisfying activities and the need to interact with peers in real life. Moreover, a number of structural game characteristics have been found to increase the risk for developing Internet gaming addiction, namely online relative to offline gaming,61 positive reinforcement,62 the enjoyment of particular game features, such as adult content, finding rare in-game items, and watching game cut scenes,63 and viewing one’s virtual persona as better than oneself.64 These characteristics indicate that particular games can be more addictive than others,15 which appears important for game developers and public prevention campaigns that focus on decreasing risk and raising awareness of potential problems. Prevention campaigns could target school-aged children, teachers, and parents in education settings. They could be based on the principles of providing information and a discussion platform concerning Internet and gaming use and possible negative consequences via psychoeducation, with the ultimate goal of encouraging healthy media use. Success could be determ ined over the long term using triangulation of data and reports obtained from the targeted populations.

Perry’s Dialogue

In Perry’s Dialogue, he introduces three fictional characters to explore the concept of personal identity. This topic arises as the character, Gretchen Weirob, lays on her deathbed seeking consolation from her friend, Sam Miller, and former student, Dave Cohen, to discuss the possibility of her survival after death. Weirob’s view is that people are identified by their bodies and that their continued existence relies on the existence of their living bodies (Perry, 319).In this paper, I will argue on behalf of her viewpoint approaching personal identity through Locke’s memory theory using the distinction that real memory can only be associated with the body experiencing it. Personal identity has proven to be a very controversial topic in this dialogue. By the second night, it was argued to be defined neither by the bodily existence nor the existence of an immaterial soul (320). Instead, identity is approached by the concept of person-stages (322).This idea implies that a person lives in consecutive stretches of consciousness connected in a logical manner. In this case, each stretch of consciousness indicates the all thoughts and emotions experienced by a person at a given moment in time (322). This leads to the Memory Theory of personal identity, which Miller suggested according to his readings on Locke. It basically states that all the past events occurring within this stream of consciousness forms memory and our personal identity consists of the accumulation of memory that can be traced linearly through it (322).Weirob was not able to find any flaws in this theory. However, many flaws would surface without the examination of what constitutes as memory? Weirob brings up the comparison of real and apparent memory due to the possibility of deception where a person may â€Å"seems to remember† (323) something entirely inaccurate. Real memory is then defined as an experience remembered by the person who was present at the time of that exp erience(324).Apparent memory is when someone â€Å"seems to remember† but was not actually present at the experience in question (324). In the end, the real remember is the one whose memories were caused â€Å"in the right kind of way† (324) which led Weirob to conclude that â€Å"a person is certain sort of causal process. † (324) This continued to support her belief that personal identity is coexistent with bodily continuity as all her memories were formed by the actions and brain activity of her body. With a stroke of ngenuity, Miller was able to dispute her belief that personal identity lies solely within the confines of bodily identify by stating that one can identify his/herself without examination of his or her physical body (320). He says that a person is able to wake up and realize that they are the person they were the day before, prior to opening his/her eyes. He further proves this using Kafka’s Metamorphosis, which involves the instance of so meone waking up in the body of a cockroach (320). This person still maintains the sameness of person despite the difference of body.Earlier on, Weirob had brought up the case of anticipation. She had concluded that in order for her to accept the possibly of life after death, she must believe that she can exist in another form in which she would be able to anticipate the experiences of her future self and remember the experiences of her past (323). As Miller was able to dispute her belief that personal identity is only bodily identity, he then tempts her to imagine that there will be someone in the future who will remember the conversation they are having and all her past experiences.However, this fails to comforts Weirob as she argues that this merely suggests the possibility of a deluded imposter harboring her memories (323). Once again the issue of real versus apparent memory detains Miller in his efforts. This led to the introduction of an additional restriction to Miller’ s suggestion. To provide the distinction between real and apparent memory, the heavenly person must now be the person who actually performed the actions that he/she remembers (323). So if Weirob can imagine such a person being she, then the possibility of her survival is ensured.Nevertheless, this proves to be too ambiguous for Weirob to accept. She argues that There is no assurance that the heavenly being will be identical to her as opposed to exactly similar(325). She says that if God were able to create one such being on heaven, what is to prevent him from creating two or even three? Since God is all-powerful and not limited in his abilities, he should be able to create an infinite number of Gretchen Weirobs, all of whom would hold her memories (325). These Gretchen Weirobs cannot all be her, so the possibility of her survival is once again irrational.Cohen then points out that Miller was asked only to provide the possibility of survival, so if Weriob were to imagine that God, be ing benevolent, choose to create only one heavenly Gretchen Weirob, then she cannot deny the possibility of her survival (325). To this Weirob replies that she cannot base her survival on such insubstantial conditions; she cannot tolerate that her survival depends on the right relationship between her memory to the memory of the heavenly being as well as the lack of competition of other heavenly beings(325).She says that if there is a possibility if two heavenly Gretchen Weirobs, she would be neither of them as one cannot be identical to two; then memory alone cannot provide the basis for identity. Therefore, even if there were to be only one heavenly being containing her memory, she cannot confirm that it will be identical to her (326). I agree with Weirob’s belief that she will cease to exist upon the expiration of her body. From a biological point of view, there is no earthly evidence that suggest the continuation of a person after the end of his/her brain function.Like We irob suggested, it is her brain that involves the storage of information including the accumulation of her memories(321). If her brain were to stop functioning, all her memories would logically be lost. Meanwhile, there is the case where the body can continue to function without support from the brain. This is commonly known as a coma, a state in which a person is without brain activity and within this state of mind that person can be pronounced legally dead by a qualified physician. Now on the topic of survival after death, the existence of a God must be involved.In this instance, the identity of a person can be suggested to continue if God were to create a heavenly being containing all of the deceased past memories. The possibility of survival through this case is disrupted as Weriob proved that these beings would be nothing more than exactly similar to her(323). She maintains that memory alone cannot ensure the essence of her personal identity, as God can create many heavenly bei ngs containing her memories out of which one of them would be her (323).Her idea of bodily continuity is proven to be the only rational method to interpret her existence as her steam of consciousness containing all the memories that comprises her personal identify ends with her death. However, Weirob’s belief seems to exclude those who are distorted or incapable in their ability to store memory. For example, in the case of the hypnosis mentioned in the second night, the rememberer induced to remember Weirob’s memories is disrupted in his/her stream of consciousness. 323) Yet, after the removal of the trance, he/she will continue to exist as him/herself. Weirob also mentioned people who â€Å"seem to remember† being Napoleon losing the battle of waterloo 323). Although these poeple are visibly not Napoleon, they are also not considered to be nonexistent despite lack of personal identity. Other cases include patients of Alzheimer’s disease who will graduall y lose all their memories or those living with mental illness who are under delusions of who they really are.These people are obviously experiencing inaccurate representations for their personal identity. Nevertheless, this does not prevent these individuals from existing. While it is correct that these individuals exist, I can argue that there is a distinction between seeming to exist and actually existing. Individuals suffering from delusions exist within their own mind, without relation to the their actual environment. They seem to exist, either as Napoleon or as Gretchen Weirob, in that stretch of consciousness.The mind is inarguably still a part of the body so while they may be not physically experiencing these events, their body, or more specifically their brain, is still needed for the creation of these memories. Therefore, they will follow the same laws of existence as any normal person. On the other hand, those who are suffering from Alzheimer’s, or any form of head trauma that forces them to lose their memories are simultaneously losing their identity. As stretches of their streams of consciousness fade away, their personal identity diminishes until there is nothing left to distinguish them from an empty shell, which is their body.