136 research outputs found

    Discomfort glare evaluation: the influence of anchor bias in luminance adjustments

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    Luminance adjustment is a procedure commonly used to evaluate discomfort glare and the results from adjustment experiments form the basis of some recommendations for limiting its occurrence. There are, however, strong reasons to expect that settings made using adjustment are unintentionally influenced by extraneous variables. This paper discusses bias towards the initial anchor, the setting of the variable stimulus immediately before an adjustment is made. Specifically, the initial luminance is expected to influence the setting that is made by adjustment; for example, a lower initial luminance leads to a lower setting than a high initial luminance. To investigate anchor bias, a Hopkinson-like multiple-criterion adjustment experiment was undertaken, but with three different anchors. The results confirmed significant bias: glare settings were biased towards the luminance of the initial anchor. This demonstrates a need for caution when using adjustment to explore discomfort glare and when interpreting the results of past studies that used discomfort glare models fitted to data obtained with this procedure

    Stimulus range bias leads to different settings when using luminance adjustment to evaluate discomfort due to glare

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    Luminance adjustment is widely used to evaluate discomfort due to glare. This paper reports an experiment conducted to investigate two factors of the luminance adjustment procedure, stimulus range bias and direct vs indirect control. Stimulus range bias describes the influence on subjective evaluations of the range of stimuli available to the test observer, with range being the minimum and maximum available glare source luminance in the current context. For the glare source, an artificial window, there were three ranges, having maximum luminances of 5 106, 7288 and 9469ā€Æcd/m2. The results suggest that luminance range had a significant effect on settings made, sufficient to change settings by an amount equivalent to one step of a Hopkinson-like discomfort sensation scale. The mean luminance associated with just intolerable discomfort with the low range was less than that associated with just uncomfortable with the high range. Past experiments have used direct control, where the observer makes the adjustment directly, and indirect control, where the observer instructs the experimenter to make the adjustment actions. Both methods were used in the current experiment. It was found that range bias was larger when using direct control than with indirect control. These findings contribute to an understanding of why different studies of discomfort glare have reported different results and hence proposed different discomfort models

    Discomfort glare evaluation: the influence of anchor bias in luminance adjustments

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    Luminance adjustment is a procedure commonly used to evaluate discomfort glare and the results from adjustment experiments form the basis of some recommendations for limiting its occurrence. There are, however, strong reasons to expect that settings made using adjustment are unintentionally influenced by extraneous variables. This paper discusses bias towards the initial anchor, the setting of the variable stimulus immediately before an adjustment is made. Specifically, the initial luminance is expected to influence the setting that is made by adjustment; for example, a lower initial luminance leads to a lower setting than a high initial luminance. To investigate anchor bias, a Hopkinson-like multiple-criterion adjustment experiment was undertaken, but with three different anchors. The results confirmed significant bias: glare settings were biased towards the luminance of the initial anchor. This demonstrates a need for caution when using adjustment to explore discomfort glare and when interpreting the results of past studies that used discomfort glare models fitted to data obtained with this procedure

    A Bayesian method of evaluating discomfort due to glare: the effect of order bias from a large glare source

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    Replicating scientific findings is a fundamental aspect of research. However, in studies of discomfort due to glare, it is difficult to make comparisons between the results of different experiments since the statistical tests usually reported do not allow independent findings to be directly compared to each other. Here we present an alternative Bayesian approach that can address this problem. To show how this approach works, we performed a laboratory test with 55 participants to validate the effect of order bias previously detected in a similar study evaluating discomfort due to glare but, this time, under a large luminous source. Using the luminance adjustment procedure, the glare source was varied to meet four sensations of discomfort due to glare. Adjustments were performed under three different order sequences: ascending, descending, and randomised. Test participants provided glare settings using a newly proposed evaluation scale. The effect of order bias detected in the original study was compared to the data obtained with the same methodological procedure in the new experiment using Bayesian inferential tests. The results showed a close replication, highlighting that the order bias effect found in the original study was also present in the new experiment. The wide application of Bayesian methods in the design and analysis of experimental studies may improve the accuracy and validity of glare models

    Desenvolvimento de uma versĆ£o portuguesa do nutritional risk screening NRS 2002

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    O Nutritional Risk Screening (NRS 2002) Ć© um instrumento que foi desenvolvido pela Danish Society for Parenteral and Enteral Nutrition. Trata-se de um sistema vĆ”lido que permite detetar a presenƧa do risco de desnutriĆ§Ć£o ou de desnutriĆ§Ć£o em indivĆ­duos hospitalizados e que Ć© aplicado pelos profissionais de saĆŗde. Procedeu-se ao desenvolvimento de uma versĆ£o para a lĆ­ngua Portuguesa do NRS 2002 com equivalĆŖncia linguĆ­stica e cultural ao original, recorrendo Ć  metodologia proposta pela OrganizaĆ§Ć£o Mundial da SaĆŗde "Processo de traduĆ§Ć£o e de adaptaĆ§Ć£o de instrumentos". Realizou-se uma traduĆ§Ć£o avanƧada e a retrotraduĆ§Ć£o, atravĆ©s das seguintes etapas: traduĆ§Ć£o (1.ĀŖ etapa), retrotraduĆ§Ć£o efetuada por um ou mais especialistas (2.ĀŖ etapa), prĆ©-teste (3.ĀŖ etapa) e preparaĆ§Ć£o da versĆ£o final (4.ĀŖ etapa). Este artigo tem como objetivo divulgar este processo e tambĆ©m a versĆ£o Portuguesa do NRS 2002.The Nutritional Risk Screening (NRS 2002) is a tool that was developed by the Danish Society for Parenteral and Enteral Nutrition. It is a valid system that allows the detection of the risk of undernutrition or of undernutrition in hospitalized individuals and is applied by health professionals. A Portuguese language version of NRS 2002 was developed with linguistic and cultural equivalence to the original using the WHO proposed methodology "Process of translation and adaptation of instruments". Advanced translation and back-translation were carried out through the following steps: translation (1st stage), back-translation performed by one or more specialists (2nd stage), pre test (3rd stage) and preparation of the final version (4th stage). This article aims to describe this process and also the Portuguese version of NRS 2002

    Perceived Financial Barriers to Cervical Cancer Screening and Associated Cost Burden among Low-Income, Under-Screened Women

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    Background: Despite screening's effectiveness in reducing cervical cancer incidence and mortality, disparities in cervical cancer screening uptake remain, with lower rates documented among uninsured and low-income individuals. We examined perceived financial barriers to, and the perceived cost burden of, cervical cancer screening. Materials and Methods: We surveyed 702 low-income, uninsured or publicly insured women ages 25-64 years in North Carolina, U.S., who were not up to date on cervical cancer screening according to national guidelines. Participants were asked about perceived financial barriers to screening and how much they perceived screening would cost. We used multivariable logistic regression to assess the sociodemographic predictors of perceived financial barriers. Results: Seventy-two percent of participants perceived financial barriers to screening. Screening appointment costs (71%) and follow-up/future treatment costs (44%) were most commonly reported, followed by lost pay due to time missed from work (6%) and transportation costs (5%). In multivariable analysis, being uninsured (vs. publicly insured), younger (25-34 vs. 50-64 years), White (vs. Black), and not reporting income data were associated with perceiving screening costs and future treatment costs as barriers to screening. Participants reported wide-ranging estimates of the perceived out-of-pocket cost of screening (0āˆ’0-1300), with a median expected cost of $245. Conclusions: The majority of our sample of low-income women perceived substantial financial barriers to screening, particularly related to screening appointment costs and potential follow-up/future treatment costs. Providing greater cost transparency and access to financial assistance may reduce perceived financial barriers to screening, potentially increasing screening uptake among this underserved population. Clinicaltrials.gov registration number NCT02651883

    Extreme differences in 87Sr/86Sr between Samoan lavas and the magmatic olivines they host: Evidence for highly heterogeneous 87Sr/86Sr in the magmatic plumbing system sourcing a single lava

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    .Investigations of mantle heterogeneity in ocean island basalts (OIB) frequently compare heavy radiogenic isotopes (i.e. 87Sr/86Sr), often measured in whole rock powders, with 3He/4He and Ī“18O, commonly measured in olivines. However, the 87Sr/86Sr in the olivines, which is dominated by Sr in melt inclusions, may not be in equilibrium with the 87Sr/86Sr in the whole rock. Here we present new 87Sr/86Sr measurements made on Samoan magmatic olivines, where multiple olivine crystals are aggregated for a single isotopic measurement. The olivines host abundant melt inclusions, and yielded relatively large quantities of Sr (13.0 to 100.6Ā ng) in 19 to 185Ā mg aliquots of fresh olivine, yielding high Srsample/Srblank ratios (ā‰„Ā 427). These new data on olivines show that samples can exhibit significant 87Sr/86Sr disequilibrium: in one extreme sample, where the basaltic whole rock 87Sr/86Sr (0.708901) is higher than several different aliquots of aggregate magmatic olivines (0.707385 to 0.707773), the whole rock-olivine 87Sr/86Sr disequilibrium is >Ā 1590Ā ppm. The 87Sr/86Sr disequilibrium observed between whole rocks and bulk olivines relates to the isotopic disequilibrium between whole rocks and the average 87Sr/86Sr of the population of melt inclusions hosted in the olivines. Therefore, a population of olivines in a Samoan lava must have crystallized from (and trapped melts of) a different 87Sr/86Sr composition than the final erupted lava hosting the olivines. A primary question is how melts with different 87Sr/86Sr can exist in the same magmatic plumbing system and contribute heterogeneous 87Sr/86Sr to a lava and the magmatic olivines it hosts. We explore potential mechanisms for generating heterogeneous melts in magma chambers. The reliance, in part, of chemical geodynamic models of the relationships between isotopic systems measured in whole rocks (87Sr/86Sr) and systems measured in olivines (3He/4He and Ī“18O) means that whole rock-olivine Sr-isotopic disequilibrium will be important for evaluating relationship among these key isotopic tracer systems. Moving forward, it will be important to evaluate whether whole rock-olivine Sr-isotopic disequilibrium is a pervasive issue in OIB globally

    GEANT4 : a simulation toolkit

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    Abstract Geant4 is a toolkit for simulating the passage of particles through matter. It includes a complete range of functionality including tracking, geometry, physics models and hits. The physics processes offered cover a comprehensive range, including electromagnetic, hadronic and optical processes, a large set of long-lived particles, materials and elements, over a wide energy range starting, in some cases, from 250 eV and extending in others to the TeV energy range. It has been designed and constructed to expose the physics models utilised, to handle complex geometries, and to enable its easy adaptation for optimal use in different sets of applications. The toolkit is the result of a worldwide collaboration of physicists and software engineers. It has been created exploiting software engineering and object-oriented technology and implemented in the C++ programming language. It has been used in applications in particle physics, nuclear physics, accelerator design, space engineering and medical physics. PACS: 07.05.Tp; 13; 2

    Phosphoinositide-binding interface proteins involved in shaping cell membranes

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    The mechanism by which cell and cell membrane shapes are created has long been a subject of great interest. Among the phosphoinositide-binding proteins, a group of proteins that can change the shape of membranes, in addition to the phosphoinositide-binding ability, has been found. These proteins, which contain membrane-deforming domains such as the BAR, EFC/F-BAR, and the IMD/I-BAR domains, led to inward-invaginated tubes or outward protrusions of the membrane, resulting in a variety of membrane shapes. Furthermore, these proteins not only bind to phosphoinositide, but also to the N-WASP/WAVE complex and the actin polymerization machinery, which generates a driving force to shape the membranes
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