Physical systems in Canada and US Essay Example | Topics and Well Written Essays - 750 words

Physical systems in Canada and US - Essay Example The land area of these countries runs from the Arctic Ocean to the Gulf of Mexico. The Pacific Ocean parallels the coastal region of Canada and the U.S. Furthermore, tectonic forces formed the mountainous ranges of these countries millions of years ago. They include the Cascade Range, Coast Range, Alaska range, and Sierra Nevada (National Geographic, 2013). It is believed that from 500 million year of old rocks present at permission gap to contemporary windblown sand dunes at Canyon, geologic formation or configuration of the big bend illustrate interestingly the diverse depositional styles over an enormous interval of time. For majority of the individuals, it measured by passing generations, years and days. The issue of geologic time is not easily comprehended because events that happened 20 million or as many as 100 million years are at best, hard to comprehend. During the end of the Paleozoic period, a deep ocean basin or trough expanded from modern day Oklahoma and Arkansas into the big bend place of the West Texas. Sands and sediments from the highlands to the north formed and accumulated in that basin or trough to create layers or sheets of sand, clay, and gravel. With time, these sheets melted into shale beds and sandstones. Canada and the U.S are experiencing strain on environmental resources because of increased population. The environment determines the use of resources meets human requirement while preserving and maintaining the environment in order to ensure that that human needs can be met in present and in the future. Distribution of human population affects environmental resources, regions that people live, and consumption patterns. It is rational to state that more people needs more environmental resources and produce more waste which pose a greater challenge to the environment (National Geographic, 2013). The rapidly growing population is experiencing a scenario whereby many people

Dog whistle Essay Example for Free

Dog whistle Essay The win for republicans relied on two factors. They played in the areas they were the weakest and they targeted voters and groups of voters. This was known as the â€Å"dog whistle† implying that Bush’s speech was only heard by those targeted groups. They kept away for the conventional political indicators such as economy, jobs and health. â€Å"The Bush strategists found a new way to identify and communicate with potential supporters† (Morgan, 2005). By doing this it changed the established ideas of what elections are about and why individuals vote the way they do. John Kerry’s lead was only in indicators that usually determined winner or loser in western democracies. â€Å"Majorities, sometimes large majorities, favored abolishing offshore tax havens, reforming healthcare writing labor and environmental protections into trade accords, and protecting benefits levels and spending on education and health, while 45 per cent opposed Bush’s tax cuts for the rich† ( Morgan, 2005). All of the tax policies were supported in the Democratic Party. Republicans strategy was to play on the conservative voters hoping to draw them to the polls by appealing to their most basic values, fears and prejudices. They also plagued Kerry’s campaign with hints about his trustworthiness. â€Å"Research by the University of Wisconsin indicates the Republicans ran 101,000 advertisements attacking Kerry’s character, while up to 95 percent of Kerry’s ads were based on issues† ( Morgan, 2005). When looking at the reasons why 35 percent said it was because they didn’t trust him. Another 23 percent didn’t because of his stance on gay marriage and 18 percent because of the issue of abortion. The Republicans also relied on TargetPoint a republican firm that relied on every database that the republicans could get then; they cross referenced this to the buying power of the citizens. This would enable direct mail marketers, telephone volunteer and door to door campaigning. This type of marketing is effective and was seen all across America. I can’t count how many people I came across during that elections that would have some type of comment on how much they got in the mail or how many phone calls they received during this time. I don’t really want to call his issue â€Å"feel good† but rather conservative rationale mixed with fear that gave the vote towards the Republican side of the yard. Reference: Magleby, D. B. , O’Brien, D. , Light, P. , Peltason, J. W. , Cronin, T. E. (2006). Government by the People: National, State, and Local 21st. Ed. New Jersey: Prentice Hall. Morgan, S. ( March 18, 2005). It worked for Bush. New Statesman. 134(4736).

Effects of Prevalence Expectation on Visual Search Behaviour

Effects of Prevalence Expectation on Visual Search Behaviour Page | 1 Introduction The objective of this research is to investigate the effects of prevalence expectation on visual search behaviour and cognitive function in radio-diagnosis of the adult chest radiograph and its impact upon medical expert witness testimony in malpractice litigation. Research into radiological error has consistently demonstrated disparity in radiological performance. Most studies of radiology error report significant rates of intra and inter observer variability. The pertinent question is why do radiologists make mistakes? â€Å"Conventionally, radiologists produce diagnoses on the basis of a combination of their training, experience, and individual judgment. Radiologists perceive and recognise image patterns and associate or infer a diagnosis consistent with those patterns.† [1] Accurate results depend upon the radiologist’s ability to recognise a lesion, ignore irrelevant details, and retrieve pertinent memories in order to accurately interpret an image. The radiologists primary task is to accurately identify a range of anatomical structures and pathological findings on medical images. The diagnostic process in radiology is not well understood. Basically, radiologists perceive and recognise image patterns and then associate or infer a diagnosis consistent with such patterns. Appearances on a radiograph are silhouettes of normal and abnormal anatomy. Each shadow represents a projection of layers of detail on a two dimensional surface from a three-dimensional object. The successful detect ion of the target and the time required to seek it out depends upon a number of external factors Much information needs to be processed by the radiologist during the interpretation of such shadows. The disease pattern, The clinical and demographic information relating to the patient The differential diagnoses pertaining to such a pattern. The experience of the radiologist A general aspect of everyday life is looking for a particular target amongst an assortment of other (distracting) items. Visual Search is one task that is performed routinely from radiological diagnosis to finding a definitive research text in a library. Visual search is an essential element in the cognitive process and is the interaction between the visual system, its target and the reader’s subsequent decision. Each experiment was conducted in a controlled laboratory environment, but were designed to simulate, as near as possible, the clinical arena. Expectation is explored by manipulating the information given to radiologists between general clinical information and very specific clinical information, thereby encouraging each radiologist to formulate an individual expectation of abnormal prevalence in the images presented to them. We then measured any subsequent change in behaviour as the subjects’ biases shifted. It was hypothesised thata radiologist would vary their decisions at the cost of more or less false alarms. This is termed criterion shift. The amount by which a radiologist considers false alarms to achieve a higher rate of detection is termed the bias. Bias represents an approach to lessen the consequences of a missed target. What is visual search? In a visual search task, subjects look for a target item among a number of distracting items. [1] After breaking down an image into its distinct components, the visual system directs attention to unusual areas for further analysis. This act of looking for and selecting an anomalous feature on a radiographic image is termed visual search, and is the task performed by radiologists daily. At a very basic level, there are generally considered two types of visual search termed pre-attentive and attentive. A great deal of research has been conducted regarding the differences between these two types of visual search and the factors that affect performance during each [2, 3]. Pre-attentive search has been given a number of labels including efficient search, parallel search, easy or effortless search [1] and automatic detection [4]. In this type of search, the targets are anticipated to contain features which are processed pre-attentively [5], basically drawing attention to themselves. In this type of search, the target appears immediately to the observer, requiring little search effort. For example when searching for the letter X on a page of letter Os or for a red target in a mass of blue targets. Attentive search also referred to as inefficient search [1] serial search [4] and controlled search [2] refers to a complicated search in which attention must be given to targets much less obvious. These components are influenced respectively by the characteristics of the environment (e.g., saliency of targets and distracters) and learned search strategies. The distinction between these two types of search is consistent with the view that search is driven by both bottom up and top down processes [6] wherein bottom up processes drive attention due to salient features in an environment or target features and top down processes drive attention through the function of search strategies such as the direction of attention to locations of high priority. Experienced radiologists develop a mental global impression of a standard radiograph [7, 8] sometimes called a target template [9] and in some instances use pre-attentive search as the abnormality is almost instantaneously visible. Conversel y they may use the second approach in more difficult cases. Recognising how these factors influence target detection helps to understand real-world search tasks and cognitive psychology. Together, the results can help to show how different influences affect visual search in the performance of real-life search tasks as in medical radiology, and airport baggage security. Fiore et al [10]) define threat detection in an airport screening task as the ability to rapidly recognise targets in the environment and interpret the meaning and importance of these cues. Nodine et al [11] break the radiological interpretation task down into three elements, describing the task as consisting of a search for, the recognition of an abnormality and the decision made regarding the abnormality. Many occupations depend on the speedy and effective execution of a visual search. Surf life savers in Australia are trained to search the ocean for rips, sharks and for swimmers in difficulty. Diamond cutters need to be able to evaluate the cutting potential of a rough diamond and need to be able to look at a diamond crystal and determine whether it will yield a large enough gemstone to make a profit.The quality and price will vary greatly based on the cut quality [12]. Airport baggage security screeners are trained using Threat Image Projection (TIP) technology to detect potential threat items within an X-ray image that may contain harmless clutter. There are various features which might hamper a successful visual search, including item superimposition, different viewpoints, rotation of the item and general image complexity. A number of other demands may also influence search, including psychosocial pressure (a busy airport might provoke a too rapid search), expectation (a threat it em is a rare occurrence), boredom and the number of different targets added to the list of dangerous or suspicious items. Errors in these areas are potentially life-threatening, expensive or both. In the medical arena, diagnosis in cytology and radiology are two areas that are dependent upon visual search. Clinical understanding and proficiency in visual pattern recognition serve as the basis for diagnosis by radiologists and pathologists [13]. Error in Radiology Imaging departments must offer a top quality radiological service with as little risk to the patient as is possible. It is therefore incumbent upon radiology department to address any problematic areas and try to reduce the causes of error. The accuracy of the radiological report is one element of the patient’s care. In radio-diagnosis, errors are either of perception or cognition [14]. Perceptual errors occur when targets (tumours, infection) are not visualised. A cognitive error occurs when an abnormality is seen but the radiologist draws the wrong conclusions due to unsound diagnostic reasoning. Diagnostic errors are classified as either false positive (FP) or false negative (FN). A false positive decision is due to the interpretation of a presumed target as pathological when it is in fact normal. A false-negative is an abnormality that is present but is not perceived. FN errors errors are five times more likely than FP errors [15], whilst perceptual errors are four times more frequent than decision making errors [14]. Radio-diagnosis not an exact science. Approximately 4% of Radiological interpretations contain errors, fortunately, most of these errors are clinically insignificant, or if serious errors are found, they are promptly corrected causing no harm to patients [16]. Identifying and locating items can be challenging especially when one is uncertain of where, or even what, to look for. Difficulties are more likely to occur when observers must locate the target’s position rather than simply detect the target’s presence [17]. Numerous studies have been conducted to understand error in radio-diagnosis. This issue has been recognised for a number of years. In the 1940s, Garland [18] found that 10-20% of chest radiographs of patients with suspected tuberculosis (TB) were read differently by different observers and a study by Quekel et al [19] observed that 19% of lung cancers presenting as a nodule on chest radiographs were missed. Another study [20] identified major diagnostic variation between three experienced radiologists interpreting medical images of patients in an emergency department. In this study the level of diagnostic agreement between the radiologists varied according to the anatomical area examined. Levels of agreement were abdomen (51%), chest (61%) and musculoskeletal (74%). There are a number of influences that affect the perception and diagnosis of chest lesions. Of these influences, prevalence expectation has had very little study. Target prevalence and prevalence expectation Prevalence expectation or bias occurs when expectations about an outcome influences a subject’s behaviour. In radiology this can be a factor during diagnosis. For statistical reasons, laboratory studies of visual search in typically include targets on 50% of all trials and participants often recognise that any given trial has an equal chance of having a target or not. However, real-life searches are seldom so balanced. In airport security, baggage screeners view numerous x-ray images of suitcases, but the incidence of a dangerous item happens infrequently. Consequently, one issue in visual search is exploring how a difference in target prevalence modifies searcher expectation and subsequent detection performance. This issue has been raised in multiple domains, including vigilance studies, radio-diagnostic perception, and cognitive psychology. In routine radiological examinations, the occurrence of abnormalities is generally low. This frequency fluctuates depending on the demographics of the population and the anatomical area being examined. However, in all cases, a mis-diagnosis might result in serious consequences. Research within radiology has therefore attempted to show whether low target prevalence is responsible for diagnostic error. Whilst a number of studies, within the medical and non-medical domains, have investigated whether the number of targets present (prevalence) can affect performance. [21, 22, 23, 24], there has been almost no research undertaken regarding the effect of prevalence expectation.

Nanotechnology: Immortality Or Total Annihilation? :: essays research papers

Technology has evolved from ideals once seen as unbelievable to common everyday instruments. Computers that used to occupy an entire room are now the size of notebooks. The human race has always pushed for technological advances working at the most efficient level, perhaps, the molecular level. The developments and progress in artificial intelligence and molecular technology have spawned a new form of technology; Nanotechnology. Nanotechnology could give the human race eternal life, or it could cause total annihilation. The idea of nanotech was conceived by a man named K. Eric Drexler (Stix 94), which he defines as "Technology based on the manipulation of individual atoms and molecules to build structures to complex atomic specifications (Drexler, "Engines" 288)." The technology which Drexler speaks of will be undoubtedly small, in fact, nano- structures will only measure 100 nanometers, or a billionth of a meter (Stix 94). Being as small as they are, nanostructures require fine particles that can only be seen with the STM, or Scanning Tunneling Microscope (Dowie 4). Moreover the STM allows the scientists to not only see things at the molecular level, but it can pick up and move atoms as well (Port 128). Unfortunately the one device that is giving nanoscientists something to work with is also one of the many obstacles restricting the development of nanotech. The STM has been regarded as too big to ever produce nanotech structures (Port 128). Other scientists have stated that the manipulation of atoms, which nanotech relies on, ignores atomic reality. Atoms simply don't fit together in ways which nanotech intends to use them (Garfinkel 105). The problems plaguing the progress of nanotech has raised many questions among the scientific community concerning it's validity. The moving of atoms, the gathering of information, the restrictions of the STM, all restrict nanotech progress. And until these questions are answered, nanotech is regarded as silly (Stix 98). But the nanotech optimists are still out there. They contend that the progress made by a team at IBM who was able to write letters and draw pictures atom by atom actually began the birth of nanotech (Darling 49). These same people answer the scientific questions by replying that a breakthrough is not needed, rather the science gained must be applied (DuCharme 33). In fact, Drexler argues that the machines exist, trends are simply working on building better ones ("Unbounding" 24). Drexler continues by stating that the machines he spoke about in "Engines of Creation" published in 1986 should be

The Long-term Safety and Effectiveness of Low-Carbohydrate Diets :: Health Nutrition Diet Exercise Essays

  Ã‚  Ã‚  Ã‚  Ã‚  As the obsession with "losing weight" continues, many people are turning to low-carbohydrate diets such as the Atkins diet. With total book sales over 45 million, many doctors are starting to ask questions about the safety of a high fat, high protein diet. There have been many short-term studies reporting that a low-carbohydrate diet can be effective for weight loss. Unfortunately, most studies have been based on data collected for 90 days or less. Dieters and Doctors alike could benefit from long-term studies reporting on safety and weight loss after a year or more. In 2003, there were three trials reporting on the long-term effectiveness and side effects of the Atkins diet. These studies followed obese dieters who were following the Atkins low-carbohydrate diet. The results were then compared to the standard low-fat diet, which has been recommended by doctors for years. From the results of these studies we must decide if weight loss equals health and what should be considered acceptable risk?   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Weight loss was the primary focus of most of the studies done on the Atkins diet. Dieters are looking for results and a decrease in weight, not necessarily fat, is the ultimate goal. All three studies showed greater weight loss after six months of a low-carbohydrate diet than the same time spent on a low-fat diet. On average low-carbohydrate dieters lost about 4kgs, or roughly 9lbs, more than the low-fat dieters. This is one reason why the Atkins diet has become so popular; dieters see results more quickly. Many people are only on the diet for a few months and then go back to eating normally. For those that stick with it, it was found that after twelve months there was no longer a significant difference in weight loss between the low-fat and the low-carbohydrate groups. Although result happened quickly, in the long run the Atkins diet didn’t prove to be any more effective at weight loss than the low-fat diet. Studies of more than a year are nearly non-existent and the studies referred to here contain flaws. More research needs to be done before we can reach a definitive answer. At the moment, it seems that for the first 3-6 months the Atkins diet may be more effective than a low-fat diet. In the long term however there is no indication that a low-carbohydrate diet is better. For both diets, participants had trouble following the guidelines and many

To work or not to work? :: Journalism Journalistic Papers

To work or not to work? Why the educated homemaker is opting out of the workplace and why other women are not It’s 5 a.m. and Laura Williams squints at her computer’s bright light. She presses the letters on her keyboard and replies to as many emails as she can before another busy day at her full-time job begins. After she makes breakfast for her family, her husband Ryan gets their daughters, Emma, 4, and Anna, 18 months, ready. Then the Williams family sets out to drop Emma at pre-school, and then mom and Anna drop dad at work. Sounds like your typical family morning: the family gets ready, the kids go off to school, and mom and dad go off to work, right? Well, sort-of. Seven years ago, 29-year-old Laura Williams was living the professional life she always imagined. Armed with a degree in social work from Cornell, Williams had an impressive resume that could practically name her job of choice. But today, she’s living the life she never imagined she would have: she’s a stay-at-home mom. Williams is a part of a growing national trend where educated women earning good salaries temporarily ‘opt out’ of the workplace to take care of their children. With professional experience ranging from public relations at XEROX to handling media affairs for 1997 U.S. Poet Laureate Robert Pinsky at Boston University, Williams had employers from Rochester, N.Y. and Cambridge, Mass. offering her higher paying and higher power jobs. But the newly married, successful professional was also thinking about starting a family. So Williams turned down these career advancing offers and continued at the Boston University Public Relations Office. â€Å"I knew early on that I did not want an 80-hour per week job,† said Williams. â€Å"Getting a graduate degree, working part-time, and starting a family are three things that did not mesh.† Williams, 36, who described herself as a go-getter, said she always felt ambitious while growing up. â€Å"I knew I wanted to work professionally,† she said. â€Å"I always thought I would work part-time and have children.† But after working at BU through her first pregnancy and simultaneously taking graduate classes at the university, Williams became anxious; yet she wasn’t ready to walk away. â€Å"This was definitely the most stressful time in my life,† said Williams, whose own mom was a stay-at-home mom. â€Å"At the time you think you can do it all, but finally I approached my boss and convinced him to let me work from home.

Changing Self Essay Essay

How do composers use texts to explore concepts of Changing Self? Discuss ideas and techniques. In Gwen Harwood’s poems Prize-Giving and The Glass Jar, the prescribed text Sky-High, and the novel White Teeth by Zadie Smith, the composer have used many varying ideas and techniques to investigate and illustrate concepts of Changing Self effectively. The ideas looked at in Gwen Harwood’s poetry include imagery, retrospect, metaphor, and inversion of the connotation of adjectives. Ideas conveyed in Sky-High include imagery, retrospect, and comparison. The techniques and ideas in White Teeth, to name the most important, are long and erratic chronology, removing characters for a period and the exposing of the least important change are evident in the texts that are compared. In Gwen Harwood’s poem Prize-Giving, the composer has adeptly used imagery to examine and represent the Changing Self evident in this poem. This striking imagery at first portrays an egotistical middle aged man, such as his inurbane behaviour when he â€Å"scowled with violent distaste†. This works in revealing the major change of Eisenbart, in comparing the self-righteous man at the start of the poem, to the awkward and confused man at the end. The imagery used to describe the titian haired girl is also evocative, especially when comparing her supposed insignificance in contrast to Eisenbart, and the affect she has on him. She seems to be nothing but a cheeky, though attractive, schoolgirl: â€Å"one girl sat grinning.† This thought of her insignificance is reinforced when she â€Å"winked at nearby friends†, possibly reinforcing to Eisenbart her immaturity that was earlier established through her audacious behaviour during the opening prayer. However, Eisenbart was flung from his â€Å"calm age and power† merely by a touch of this ‘immature schoolgirl’, indicating a change. This change in the girl’s attitude is reinforced when she changed â€Å"her casual schoolgirl’s for a master’s air†, indicating the power that she has that Eisenbart has not detected thus far. In the text Sky-High by Hannah Robert, the concept of Changing Self is analysed and emphasized through retrospect, apt imagery, and change of language. â€Å"The best climbing tree† indicates the experiences of a child and their joy in everything no matter how small. However, the responsibility in the statement â€Å"it is unlikely the washing line could support me† divulges that the persona is now more responsible, and, it is discovered, also older, revealing a physical change of self. The comparisons in the final stanza show the insight that the persona now has; as seen in â€Å"I was once the curious onlooker, I now write my own semaphore secrets in colourful t-shirts†. It also shows, however, that no matter how much a person changes, that he or she is still the same person, and that they still retain what they were before. The metaphors used in The Glass Jar, and the way in which they are developed and often exaggerated, shows and typifies the change of self that is experienced by the persona, so that greater audiences may understand the experiences of a small child. Only a small child could imagine an ordinary glass jar as a â€Å"monstrance† in which the sun could be caught for the night. This vision of the â€Å"holy commonplace of field and flower† coming to save the boy is lost when he awakes from his nightmares. The religious metaphor is now lost except for the mocking image of the â€Å"resurrected sun† in the final stanza. The inversion of the usual use of adjectives shows the confusion associated with the change of self for the persona, such as the â€Å"malignant ballet†. The novel White Teeth, by Zadie Smith, develops the concept of Changing Self with a long and somewhat inconsistent chronology. All the characters in this novel, which reaches from World War Two to the end of the century, obviously change physically due to this long chronology. However, the retrospect as to how much the characters have changed in other ways is far more potent because of the extensive chronology. The comparison, for example, Josh Chalfen turning away from his family and becoming less of a nerd: he was the kind of guy â€Å"who could measure an eighth with his eyes closed (so fuck you, Millat)†. The original focus of the book on Archie Jones beguiles the reader into thinking that he is the main focus for the book. However, Archie serves  merely as a connection between all the original characters. From these characters the Jones, Iqbal, Chalfen and Bowden families and their stories emerge, and all the adults, in the end, only accentuate the changes that the children (Irie, Millat, Magid, and Josh) undergo, that is, comparing where the children have ended up to what their parents expected of them. The later and extended focus of the novel on Millat Iqbal, who changes in the most radical way out of all the characters, hides the slow and, in the sense that Millat changes, insignificant changes of Irie Jones, but her changes are more symbolic and emotional. The removal of Magid from the story means that his change of self seems sudden, because the persona is taken away at the age of nine years and only returned at the age of seventeen. In the texts Prize-Giving and The Glass Jar by Gwen Harwood, Sky-High by Hannah Robert, and White Teeth by Zadie Smith, ideas and techniques are flaunted in terms of how they are used to display the change of self in the personas. The numerous ideas used in each of the texts, often overlapping to be used in more than one text show the skill of the composers and their flexibility in applying various techniques.