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Work Indicating (work + indicating)
Selected AbstractsPoint of View: Could glucose be a proaging factor?JOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2008Eva Kassi Abstract There is an ever-increasing scientific interest for the interplay between cell's environment and the aging process. Although it is known that calorie restriction affects longevity, the exact molecular mechanisms through which nutrients influence various cell signalling/modulators of lifespan remain a largely unresolved issue. Among nutrients, glucose constitutes an evolutionarily stable, precious metabolic fuel, which is catabolized through glycolytic pathway providing energy in the form of ATP and consuming NAD. Accumulating evidence shows that among the important regulators of aging process are autophagy, sirtuin activity and oxidative stress. In light of recent work indicating that glucose availability decreases lifespan whilst impaired glucose metabolism extends life expectancy, the present article deals with the potential role of glucose in the aging process by regulating , directly through its metabolism or indirectly through insulin secretion , autophagy, sirtuins as well as other modulators of aging like oxidative stress and advanced glycation end-products (AGEs). [source] Evidence for top predator control of a grazing ecosystemOIKOS, Issue 11 2008Douglas A. Frank The importance of top predators in controlling ecological processes in large, intact ecosystems is unclear. In grasslands that support abundant ungulates, top,down control by predators may be particularly important, because of the tight biogeochemical linkages of ungulate prey with plants and soil microbes. Here, I examined the effects of the recent reintroduction of the gray wolf Canis lupus on ecosystem processes in Yellowstone National Park, where herds of grazing ungulates previously have been shown to stimulate several processes, including soil net nitrogen (N) mineralization. Rates of ungulate grazing intensity and soil net N mineralization were compared before and after wolf reintroduction in grasslands ranging five-fold in aboveground production. Grazing intensity and grassland net N mineralization declined after wolf reintroduction, a likely partial function of fewer ungulates; wolf predation has been one of several factors implicated in causing the decline in Yellowstone ungulates. In addition, the spatial pattern of grazing and net N mineralization changed after reintroduction. A shift in the spatial patterns of grazer-associated processes is consistent with a growing body of work indicating that wolves have changed habitat use patterns of ungulates in Yellowstone National Park. These findings suggest widespread wolf effects on ungulate prey, plants, and microbial activity that have spatially reorganized grassland energy and nutrient dynamics in Yellowstone Park. [source] The Mallett Fixation Disparity Test: influence of test instructions and relationship with symptomsOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 5 2006Rajula Karania Abstract Fixation disparity is a minute ocular misalignment under conditions of binocular single vision and is typically detected in primary eye care practices in the UK using the Mallett Unit Fixation Disparity Test. This instrument creates natural viewing conditions, when the patient's binocular system is fused using both central and peripheral fusion locks. This allows the examiner to determine the minimum prism power that eliminates the fixation disparity: the associated phoria or aligning prism. The spherical power that eliminates the fixation disparity, the aligning sphere, can also be determined. The near Mallett Unit Fixation Disparity Test has been shown to have good sensitivity and specificity for detecting symptomatic heterophoria. Cases of decompensated heterophoria tend to have a fixation disparity and the aligning prism or aligning sphere is a good indicator of the correction that will render the heterophoria compensated. The purpose of this study was, for the first time, to investigate the effect of test instructions on the results of the Mallett Unit Fixation Disparity Test. In study 1, we surveyed and observed practitioners to determine the instructions that are typically used. In study 2, we compared results obtained with this ,standard' method of questioning with a more ,specific' form of questioning that has been suggested in the literature. The participants for study 2 were 105 patients aged 7,70 years who were randomly selected from those attending a community optometric practice. Significantly different results were obtained with the two sets of instructions. The specific form of questioning revealed more cases of fixation disparity and the results with this method showed a better correlation with symptoms. This only held for near vision: for distance vision, symptoms were not significantly correlated with the presence of fixation disparity. This agrees with previous work with the Mallett unit, which showed a significant relationship with symptoms only at near. We also found that patients with more severe symptoms had greater degrees of aligning prism. Our study supports previous work indicating that the Mallett unit is a useful tool for detecting symptomatic heterophoria at near. However, we found that the testing method is important: patients need to be asked not just whether the nonius strips are aligned but also whether one or both of the strips ever moves. More research is needed to investigate the significance of precise test instructions in other optometric and orthoptic tests. [source] Racial Perceptions and Evaluative Responses to Welfare: Does Education Attenuate Race-of-Target Effects?POLITICAL PSYCHOLOGY, Issue 5 2005Christopher M. Federico A growing body of research indicates that welfare attitudes may be strongly shaped by negative perceptions of Blacks. This raises questions about what might inhibit the racialization of welfare attitudes. In this vein, a long line of work indicating that education leads to increased tolerance suggests that the relationship between negative racial perceptions and welfare attitudes may be weaker among the highly educated. However, recent studies suggest that the role of education may be more complex: While negative racial perceptions may be less prevalent among the highly educated, the relationship between these perceptions and policy attitudes appears to be stronger among highly educated individuals. The present study attempts to extend this finding by examining the hypothesis that the presence of a racial cue would be more (rather than less) likely to strengthen the relationship between negative racial perceptions and evaluative responses to welfare among college-educated Whites. Data from a survey-based experiment included in the 1991 National Race and Politics Study provided a clear pattern of support for this hypothesis. [source] Accountability and the Camera Perspective Bias in Videotaped ConfessionsANALYSES OF SOCIAL ISSUES & PUBLIC POLICY, Issue 1 2001G. Daniel Lassiter Prior research indicates that altering the perspective from which a videotaped confession is recorded influences assessments of the confession's voluntariness. The present study examined whether increasing decision makers' sense of accountability attenuates this biasing effect of camera perspective. Participants in a high-accountability (but not a low-accountability) condition were told that they would have to justify their judgments concerning the voluntary status of a video-taped confession to a trial judge. Although supplementary measures indicated that high-accountability participants processed information contained in the video-taped confession more carefully and thoroughly, the camera perspective bias persisted. This result adds to a growing body of work indicating that the criminal justice system needs to be seriously concerned with how it acquires and utilizes videotaped confession evidence. [source] | ||||||||||