618 resultados para Field evidence


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Arachidonic acid metabolism through cyclooxygenase (COX) pathways leads to the generation of biologically active eicosanoids. Eicosanoid expression levels vary during development and progression of gastrointestinal (GI) malignancies. COX-2 is the major COX-isoform responsible for G.I. cancer development/progression. COX-2 expression increases during progression from a normal to cancerous state. Evidence from observational studies has demonstrated that chronic NSAID use reduces the risk of cancer development, while both incidence and risk of death due to G.I. cancers were significantly reduced by daily aspirin intake. A number of randomized controlled trials (APC trial, Prevention of Sporadic Adenomatous Polyps trial, APPROVe trial) have also shown a significant protective effect in patients receiving selective COX-2 inhibitors. However, chronic use of selective COX-2 inhibitors at high doses was associated with increased cardiovascular risk, while NSAIDs have also been associated with increased risk. More recently, downstream effectors of COX-signaling have been investigated in cancer development/progression. PGE 2, which binds to both EP and PPAR receptors, is the major prostanoid implicated in the carcinogenesis of G.I. cancers. The role of TXA 2 in G.I. cancers has also been examined, although further studies are required to uncover its role in carcinogenesis. Other prostanoids investigated include PGD 2 and its metabolite 15d-PGJ2, PGF 1α and PGI 2. Targeting these prostanoids in G.I. cancers has the promise of avoiding cardiovascular toxicity associated with chronic selective COX-2 inhibition, while maintaining anti-tumor reactivity.A progressive sequence from normal to pre-malignant to a malignant state has been identified in G.I. cancers. In this review, we will discuss the role of the COX-derived prostanoids in G.I. cancer development and progression. Targeting these downstream prostanoids for chemoprevention and/or treatment of G.I. cancers will also be discussed. Finally, we will highlight the latest pre-clinical technologies as well as avenues for future investigation in this highly topical research field. © 2011 Elsevier B.V.

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Purpose: In animal models hemi-field deprivation results in localised, graded vitreous chamber elongation and presumably deprivation induced localised changes in retinal processing. The aim of this research was to determine if there are variations in ERG responses across the retina in normal chick eyes and to examine the effect of hemi-field and full-field deprivation on ERG responses across the retina and at earlier times than have previously been examined electrophysiologically. Methods: Chicks were either untreated, wore monocular full-diffusers or half-diffusers (depriving nasal retina) (n = 6-8 each group) from day 8. mfERG responses were measured using the VERIS mfERG system across the central 18.2º× 16.7º (H × V) field. The stimulus consisted of 61 unscaled hexagons with each hexagon modulated between black and white according to a pseudorandom binary m-sequence. The mfERG was measured on day 12 in untreated chicks, following 4 days of hemi-field diffuser wear, and 2, 48 and 96 h after application of full-field diffusers. Results: The ERG response of untreated chick eyes did not vary across the measured field; there was no effect of retinal location on the N1-P1 amplitude (p = 0.108) or on P1 implicit time (p > 0.05). This finding is consistent with retinal ganglion cell density of the chick varying by only a factor of two across the entire retina. Half-diffusers produced a ramped retina and a graded effect of negative lens correction (p < 0.0001); changes in retinal processing were localized. The untreated retina showed increasing complexity of the ERG waveform with development; form-deprivation prevented the increasing complexity of the response at the 2, 48 and 96 h measurement times and produced alterations in response timing. Conclusions: Form-deprivation and its concomitant loss of image contrast and high spatial frequency images prevented development of the ERG responses, consistent with a disruption of development of retinal feedback systems. The characterisation of ERG responses in normal and deprived chick eyes across the retina allows the assessment of concurrent visual and retinal manipulations in this model. (Ophthalmic & Physiological Optics © 2013 The College of Optometrists.)

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The Australian Commission on Safety and Quality in Health Care commissioned this rapid review to identify recent evidence in relation to three key questions: 1. What is the current evidence of quality and safety issues regarding the hospital experience of people with cognitive impairment (dementia/delirium)? 2. What are the existing evidence-based pathways, best practice or guidelines for cognitive impairment in hospitals? 3. What are the key components of an ideal patient journey for a person with dementia and/or delirium? The purpose of this review is to identify best practice in caring for patients with cognitive impairment (CI) in acute hospital settings. CI refers to patients with dementia and delirium but can include other conditions. For the purposes of this report, ‘Hospitals’ is defined as acute care settings and includes care provided by acute care institutions in other settings (e.g. Multipurpose Services and Hospital in the Home). It does not include residential aged care settings nor palliative care services that are not part of a service provided by an acute care institution. Method Both peer-reviewed publications and the grey literature were comprehensively searched for recent (primarily post 2010) publications, reports and guidelines that addressed the three key questions. The literature was evaluated and graded according to the National Health and Medical Research Council (NHMRC) levels of criteria (see Evidence Summary – Appendix B). Results Thirty-one recent publications were retrieved in relation to quality and safety issues faced by people with CI in acute hospitals. The results indicate that CI is a common problem in hospitals (upwards of 30% - the rate increases with increasing patient age), although this is likely to be an underestimate, in part, due to numbers of patients without a formal dementia diagnosis. There is a large body of evidence showing that patients with CI have worse outcomes than patients without CI following hospitalisation including increased mortality, more complications, longer hospital stays, increased system costs as well as functional and cognitive decline. 4 To improve the care of patients with CI in hospital, best practice guidelines have been developed, of which sixteen recent guidelines/position statements/standards were identified in this review (Table 2). Four guidelines described standards or quality indicators for providing optimal care for the older person with CI in hospital, in general, while three focused on delirium diagnosis, prevention and management. The remaining guidelines/statements focused on specific issues in relation to the care of patients with CI in acute hospitals including hydration, nutrition, wandering and care in the Emergency Department (ED). A key message in several of the guidelines was that older patients should be assessed for CI at admission and this is particularly important in the case of delirium, which can indicate an emergency, in order to implement treatment. A second clear mess...

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More evenly spread demand for public transport throughout a day can reduce transit service provider‟s total asset and labour costs. A plausible peak spreading strategy is to increase peak fare and/or to reduce off-peak fare. This paper reviews relevant empirical studies for urban rail systems, as rail transit plays a key role in Australian urban passenger transport and experiences severe peak loading variability. The literature is categorised into four groups: a) passenger opinions on willingness to change time for travel, b) valuations of displacement time using stated preference technique, c) simulations of peak spreading based on trip scheduling models, and: d) real-world cases of peak spreading using differential fare. Policy prescription is advised to take into account impacts of traveller‟s time flexibility and joint effects of mode shifting and peak spreading. Although focusing on urban rail, arguments in this paper are relevant to public transport in general with values to researchers and practitioners.

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We exploit a voting reform in France to estimate the causal effect of exit poll information on turnout and bandwagon voting. Before the change in legislation, individuals in some French overseas territories voted after the election result had already been made public via exit poll information from mainland France. We estimate that knowing the exit poll information decreases voter turnout by about 12 percentage points. Our study is the first clean empirical design outside of the laboratory to demonstrate the effect of such knowledge on voter turnout. Furthermore, we find that exit poll information significantly increases bandwagon voting; that is, voters who choose to turn out are more likely to vote for the expected winner.

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Research on the effects of positional concerns on individuals' attitudes and behavior is sorely lacking. To address this deficiency, we use the International Social Survey Programme 1998 data on 25,000 individuals from 26 countries to investigate the impact of relative income position on three facets of social capital: horizontal and vertical trust as well as norm compliance. Testing relative deprivation theory, we identify a deleterious positional income effect for persons below the reference income, particularly for their social trust and confidence in secular institutions. Also often a social capital-lowering effect of relative income advantage occurs, while a rise in absolute income almost always contributes positively. These results indicate that a rise in income inequality in a society too large is rather detrimental to the formation of social capital. (JEL Z130, I300, D310)

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This paper provides the first evidence showing that ownership concentration and the identity of the largest shareholder matter to the timeliness of corporate earnings, measured by a stock price-based timeliness metric and the reporting lag. Using panel data of 1276 Malaysian firms from 1996 to 2009, we find a non-linear relationship between concentrated ownership, measured by the largest shareholding in a firm, and the reporting lag but not the timeliness of price discovery. Although firms with government as the largest shareholder and political connections have a significantly shorter reporting lag, only the former are timelier in price discovery. Firms with family and foreigners as the largest shareholder however are less timely in price discovery. While the reporting lag is shorter in the period after the integration of the Malaysian Code of Corporate Governance (MCCG) into Bursa listing rules, its impact on the timeliness of price discovery is mostly immaterial.

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Using a sample of publicly listed firm in Korea from 2002 to 2006, this article examines the impact of board monitoring on firm value and productivity. We use outsider's attendance of board meetings as a proxy for board monitoring. Consistent with the commitment hypothesis, we find that outsider's attendance rate increases firm value, suggesting that attending board meeting itself is a strong signal that reflects outsider's intention to monitor insiders. While ownership of controlling shareholders negatively affects firm value, this relationship is not moderated by increased monitoring by outsiders. Our findings provide further evidence that the outside director system is less effective in chaebol-affiliated firms. Results also indicate that the effect of outsider's board monitoring activity on investor's valuation of the firm is greater than on productivity improvement of the firm. Our conclusions are robust for possible endogeneity in the relationship between firm value and board attendance by outside directors.

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Objective Do employees care about their relative (economic) position in comparison to their co-workers in an organization? And if so, does it raise or lower their performance? While the topic is widely discussed in the literature, behavioral evidence on these important questions is relatively rare. Methods This article explores the pay-performance relationship using a sports data set. The strength of analyzing such data is that sports tournaments take place in a very controlled environment that helps to isolate a relative income effect. Results Using two large unique data sets that cover 26 seasons in basketball and eight seasons in soccer (Bundesliga), we find considerable support for the idea that a relative income disadvantage is correlated with a decrease in individual performance. In addition, there does not seem to be any tolerance for income disparity based on the hope that such differences may signal that better times are ahead. Conclusions This suggests the need to consider the impact of the relative income position when designing pay-for-performance mechanisms within firms and teams.

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About 140-year changes in the trace metals in Porites coral samples from two locations in the northern South China Sea were investigated. Results of PCA analyses suggest that near the coast, terrestrial input impacted behavior of trace metals by 28.4%, impact of Sea Surface Temperature (SST) was 19.0%, contribution of war and infrastructure were 14.4% and 15.6% respectively. But for a location in the open sea, contribution of War and SST reached 33.2% and 16.5%, while activities of infrastructure and guano exploration reached 13.2% and 14.7%. While the spatiotemporal change model of Cu, Cd and Pb in seawater of the north area of South China Sea during 1986–1997 were reconstructed. It was found that in the sea area Cu and Cd contaminations were distributed near the coast while areas around Sanya, Hainan had high Pb levels because of the well-developed tourism related activities.

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With the fast development of urban sprawl and renewal in China, many buildings are “non-nature” short-lived, i.e. demolished after only a few years. For this concern, this research explores the influencing factors of short-lived buildings and provides the scientific foundation for sustainable urban management and planning. Cases for this research are 1734 buildings demolished in Jiangbei district, the middle region of Chongqing City. Internal and external factors for the short-lived buildings are identified by applying logistic analysis. The results indicate that nine factors have significant influence on short-lived buildings. This research also find that buildings with low density, utilization and compensation while high land development potential are more likely to become short-lived buildings.

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Lung cancer patients face poor survival and experience co-occurring chronic physical and psychological symptoms. These symptoms can result in significant burden, impaired physical and social function and poor quality of life. This paper provides a review of evidence based interventions that support best practice supportive and palliative care for patients with lung cancer. Specifically, interventions to manage dyspnoea, one of the most common symptoms experienced by this group, are discussed to illustrate the emerging evidence base in the field. The evidence base for the pharmacological management of dyspnoea report systemic opioids have the best available evidence to support their use. In particular, the evidence strongly supports systemic morphine preferably initiated and continued as a once daily sustained release preparation. Evidence supporting the use of a range of other adjunctive non-pharmacological interventions in managing the symptom is also emerging. Interventions to improve breathing efficiency that have been reported to be effective include pursed lip breathing, diaphragmatic breathing, positioning and pacing techniques. Psychosocial interventions seeking to reduce anxiety and distress can also improve the management of breathlessness although further studies are needed. In addition, evidence reviews have concluded that case management approaches and nurse led follow-up programs are effective in reducing breathlessness and psychological distress, providing a useful model for supporting implementation of evidence based symptom management strategies. Optimal outcomes from supportive and palliative care interventions thus require a multilevel approach, involving interventions at the patient, health professional and health service level.

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Located in the Gulf of Mexico in nearly 8,000 feet of water, the Perdido development is the world’s deepest spar and Shell’s first Smart Field in the Western hemisphere. Jointly developed by Shell, BP, and Chevron, the spar and the subsea equipment connected to it will eventually capture approximately an order of magnitude more data than is collected from any other Shell-designed and managed development currently operating in the Gulf of Mexico. This paper will describe Shell’s Smart Fields design philosophy, briefly explain the five design elements that underpin “smartness” in Shell’s North and South American operations—specifically, remote assisted operations, exception-based surveillance, collaborative work environments, hydrocarbon development tools and workflows, and Smart Fields Foundation IT infrastructure—and shed light on the process by which a highly customized Smart Fields development and management plan was put together for Perdido.

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Background: Charcot Neuro-Arthropathy (CN) is one of the more devastating complications of diabetes. To the best of the authors' knowledge, it appears that no clinical tools based on a systematic review of existing literature have been developed to manage acute CN. Thus, the aim of this paper was to systematically review existing literature and develop an evidence-based clinical pathway for the assessment, diagnosis and management of acute CN in patients with diabetes. Methods: Electronic databases (Medline, PubMed, CINAHL, Embase and Cochrane Library), reference lists, and relevant key websites were systematically searched for literature discussing the assessment, diagnosis and/or management of acute CN published between 2002-2012. At least two independent investigators then quality rated and graded the evidence of each included paper. Consistent recommendations emanating from the included papers were then fashioned in a clinical pathway. Results: The systematic search identified 267 manuscripts, of which 117 (44%) met the inclusion criteria for this study. Most manuscripts discussing the assessment, diagnosis and/or management of acute CN constituted level IV (case series) or EO (expert opinion) evidence. The included literature was used to develop an evidence-based clinical pathway for the assessment, investigations, diagnosis and management of acute CN. Conclusions: This research has assisted in developing a comprehensive, evidence-based clinical pathway to promote consistent and optimal practice in the assessment, diagnosis and management of acute CN. The pathway aims to support health professionals in making early diagnosis and providing appropriate immediate management of acute CN, ultimately reducing its associated complications such as amputations and hospitalisations.

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The first International Diabetic Foot Conference in Australia was hosted at Liverpool Hospital in Sydney during May 30-31, 2013. In response to the growing diabetes epidemic globally and more locally to Australia, the conference provided the perfect bridge for interaction between the multidisciplinary team members involved in diabetes care and the opportunity to assimilate the most up-to-date evidence-based medicine from some of the most respected researchers in the field.