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991.
Ruth H. Striegel-Moore Douglas Thompson Debra L. Franko Bruce Barton Sandra Affenito George B. Schreiber Stephen R. Daniels 《Obesity (Silver Spring, Md.)》2004,12(8):1311-1321
Objective: To describe the prevalence of night eating in a community cohort of black and white girls, using different definitions of night eating as described in the literature. Research Methods and Procedures: Three‐day food diaries collected as part of the National Growth and Health Study were examined to identify episodes of night eating, which was defined in five different ways: eating >25% of daily caloric intake after the last evening meal, eating >25% of daily caloric intake after 7 pm, eating >50% of daily caloric intake after the last evening meal, eating >50% of daily caloric intake after 7 pm, or eating between 11 pm and 4:59 am. Results: Frequency of night eating varied tremendously depending on how the behavior was defined. For the least restrictive definition (>25% of total intake after last meal), 50% to 70% of girls reported one night eating event; for the most restrictive (>50% of total intake after last meal), only 1.5% of 11‐year‐old girls' diaries and 3.5% of 19‐year‐old girls' diaries contained a night eating event. The frequency of night eating decreased dramatically (typically by a factor of 10) if the inclusion criteria required multiple night eating events in a given week. Discussion: A standard definition of night eating behavior is needed to advance the field. An agreed‐on operationalized definition that includes time of day, amount of calories consumed, and a frequency criterion would enable cross‐study comparisons and encourage the examination of developmental and clinical considerations of night eating behavior. 相似文献
992.
Much interest has focused on the conflict between feeding and vigilance. However, because predator attacks are rarely observed, the adaptive value of time spent vigilant (or non-vigilant through feeding) is difficult to ascertain. On the assumption that the tactics used by plovers (lapwings, Vanellus vanellus and golden plover, Pluvialis apricaria) to avoid attack by kleptoparasitic black-headed gulls (Larus ridibundus) and predators are similar, we develop a model predicting the probability of a gull being detected over any distance. The assumptions of the model are that (a) plovers are attacked whilst nonvigilant (crouching and handling prey) and (b) attacks lasting longer than the target plover's non-vigilant period will be detected. Over many distances there was a fairly close match between the observed and expected risk of the gull being detected. The match was better when the model assumed gulls waited 1 s prior to attacking plovers with large profitable worms. The risks of kleptoparasitism and predation are compared and the adaptive value of the close match between observed and expected curves is discussed. 相似文献
993.
Nagaphani B. Aetukuri Shintaro Kitajima Edward Jung Leslie E. Thompson Kumar Virwani Maria‐Louisa Reich Miriam Kunze Meike Schneider Wolfgang Schmidbauer Winfried W. Wilcke Donald S. Bethune J. Campbell Scott Robert D. Miller Ho‐Cheol Kim 《Liver Transplantation》2015,5(14)
The use of metallic lithium anodes enables higher energy density and higher specific capacity Li‐based batteries. However, it is essential to suppress lithium dendrite growth during electrodeposition. Li‐ion‐conducting ceramics (LICC) can mechanically suppress dendritic growth but are too fragile and also have low Li‐ion conductivity. Here, a simple, versatile, and scalable procedure for fabricating flexible Li‐ion‐conducting composite membranes composed of a single layer of LICC particles firmly embedded in a polymer matrix with their top and bottom surfaces exposed to allow for ionic transport is described. The membranes are thin (<100 μm) and possess high Li‐ion conductance at thicknesses where LICC disks are mechanically unstable. It is demonstrated that these membranes suppress Li dendrite growth even when the shear modulus of the matrix is lower than that of lithium. It is anticipated that these membranes enable the use of metallic lithium anodes in conventional and solid‐state Li‐ion batteries as well as in future Li? S and Li? O2 batteries. 相似文献
994.
Lauís?Brisolara-Corrêa Claudia?Elizabeth?Thompson Cláudia?Lemelle?Fernandes Loreta?Brand?o?de?FreitasEmail author 《Molecular genetics and genomics : MGG》2015,290(3):987-1002
The multigenic and multiallelic S-locus in plants is responsible for the gametophytic self-incompatibility system, which is important to prevent the detrimental effects of self-fertilization and inbreeding depression. Several studies have discussed the importance of punctual mutations, recombination, and natural selection in the generation of allelic diversity in the S-locus. However, there has been no wide-ranging study correlating the molecular evolution and structural aspects of the corresponding proteins in Solanum. Therefore, we evaluated the molecular evolution of one gene in this locus and generated a statistically well-supported phylogenetic tree, as well as evidence of positive selection, helping us to understand the diversification of S alleles in Solanum. The three-dimensional structures of some of the proteins corresponding to the major clusters of the phylogenetic tree were constructed and subsequently submitted to molecular dynamics to stabilize the folding and obtain the native structure. The positively selected amino acid residues were predominantly located in the hyper variable regions and on the surface of the protein, which appears to be fundamental for allele specificity. One of the positively selected residues was identified adjacent to a conserved strand that is crucial for enzymatic catalysis. Additionally, we have shown significant differences in the electrostatic potential among the predicted molecular surfaces in S-RNases. The structural results indicate that local changes in the three-dimensional structure are present in some regions of the molecule, although the general structure seems to be conserved. No previous study has described such structural variations in S-RNases. 相似文献
995.
Jonathan C. Hill Elaine Thomas Susan Hill Nadine E. Foster Danielle A. van der Windt 《PloS one》2015,10(4)
Objective
To develop and validate a patient report outcome measure (PROM) for clinical practice that can monitor health status of patients with a range of musculoskeletal (MSK) disorders.Methods
Constructs for inclusion in the MSK-PROM were identified from a consensus process involving patients with musculoskeletal conditions, clinicians, purchasers of healthcare services, and primary care researchers. Psychometric properties of the brief tool, including face and construct validity, repeatability and responsiveness were assessed in a sample of patients with musculoskeletal pain consulting physiotherapy services in the United Kingdom (n=425).Results
The consensus process identified 10 prioritised domains for monitoring musculoskeletal health status: pain intensity, quality of life, physical capacity, interference with social/leisure activities, emotional well-being, severity of most difficult thing, activities and roles, understanding independence, and overall impact. As the EuroQol (EQ-5D-5L) is a widely adopted PROMs tool and covers the first four domains listed, to reduce patient burden to a minimum the MSK-PROM was designed to capture the remaining six prioritised domains which are not measured by the EQ-5D-5L. The tool demonstrated excellent reliability, construct validity, responsiveness and acceptability to patients and clinicians for use in clinical practice.Conclusion
We have validated a brief patient reported outcome measure (MSK-PROM) for use in clinical practice to measure musculoskeletal health status and monitor outcomes over time using domains that are meaningful to patients and sensitive to change. Further work will establish whether the MSK-PROM is useful in other musculoskeletal healthcare settings. 相似文献996.
Leigh G. Torres Philip J. H. Sutton David R. Thompson Karine Delord Henri Weimerskirch Paul M. Sagar Erica Sommer Ben J. Dilley Peter G. Ryan Richard A. Phillips 《PloS one》2015,10(3)
Species distribution models (SDMs) are increasingly applied in conservation management to predict suitable habitat for poorly known populations. High predictive performance of SDMs is evident in validations performed within the model calibration area (interpolation), but few studies have assessed SDM transferability to novel areas (extrapolation), particularly across large spatial scales or pelagic ecosystems. We performed rigorous SDM validation tests on distribution data from three populations of a long-ranging marine predator, the grey petrel Procellaria cinerea, to assess model transferability across the Southern Hemisphere (25-65°S). Oceanographic data were combined with tracks of grey petrels from two remote sub-Antarctic islands (Antipodes and Kerguelen) using boosted regression trees to generate three SDMs: one for each island population, and a combined model. The predictive performance of these models was assessed using withheld tracking data from within the model calibration areas (interpolation), and from a third population, Marion Island (extrapolation). Predictive performance was assessed using k-fold cross validation and point biserial correlation. The two population-specific SDMs included the same predictor variables and suggested birds responded to the same broad-scale oceanographic influences. However, all model validation tests, including of the combined model, determined strong interpolation but weak extrapolation capabilities. These results indicate that habitat use reflects both its availability and bird preferences, such that the realized distribution patterns differ for each population. The spatial predictions by the three SDMs were compared with tracking data and fishing effort to demonstrate the conservation pitfalls of extrapolating SDMs outside calibration regions. This exercise revealed that SDM predictions would have led to an underestimate of overlap with fishing effort and potentially misinformed bycatch mitigation efforts. Although SDMs can elucidate potential distribution patterns relative to large-scale climatic and oceanographic conditions, knowledge of local habitat availability and preferences is necessary to understand and successfully predict region-specific realized distribution patterns. 相似文献
997.
Chase W. Kessinger Jin Won Kim Peter K. Henke Brian Thompson Jason R. McCarthy Tetsuya Hara Martin Sillesen Ronan J. P. Margey Peter Libby Ralph Weissleder Charles P. Lin Farouc A. Jaffer 《PloS one》2015,10(2)
Despite anticoagulation therapy, up to one-half of patients with deep vein thrombosis (DVT) will develop the post-thrombotic syndrome (PTS). Improving the long-term outcome of DVT patients at risk for PTS will therefore require new approaches. Here we investigate the effects of statins—lipid-lowering agents with anti-thrombotic and anti-inflammatory properties—in decreasing thrombus burden and decreasing vein wall injury, mediators of PTS, in established murine stasis and non-stasis chemical-induced venous thrombosis (N = 282 mice). Treatment of mice with daily atorvastatin or rosuvastatin significantly reduced stasis venous thrombus burden by 25% without affecting lipid levels, blood coagulation parameters, or blood cell counts. Statin-driven reductions in VT burden (thrombus mass for stasis thrombi, intravital microscopy thrombus area for non-stasis thrombi) compared similarly to the therapeutic anticoagulant effects of low molecular weight heparin. Blood from statin-treated mice showed significant reductions in platelet aggregation and clot stability. Statins additionally reduced thrombus plasminogen activator inhibitor-1 (PAI-1), tissue factor, neutrophils, myeloperoxidase, neutrophil extracellular traps (NETs), and macrophages, and these effects were most notable in the earlier timepoints after DVT formation. In addition, statins reduced DVT-induced vein wall scarring by 50% durably up to day 21 in stasis VT, as shown by polarized light microscopy of picrosirius red-stained vein wall collagen. The overall results demonstrate that statins improve VT resolution via profibrinolytic, anticoagulant, antiplatelet, and anti-vein wall scarring effects. Statins may therefore offer a new pharmacotherapeutic approach to improve DVT resolution and to reduce the post-thrombotic syndrome, particularly in subjects who are ineligible for anticoagulation therapy. 相似文献
998.
Arsenic-induced skin cancer is a significant global health burden. In areas with arsenic contamination of water sources, such as China, Pakistan, Myanmar, Cambodia and especially Bangladesh and West Bengal, large populations are at risk of arsenic-induced skin cancer. Arsenic acts as a co-carcinogen with ultraviolet (UV) radiation and affects DNA damage and repair. Nicotinamide (vitamin B3) reduces premalignant keratoses in sun-damaged skin, likely by prevention of UV-induced cellular energy depletion and enhancement of DNA repair. We investigated whether nicotinamide modifies DNA repair following exposure to UV radiation and sodium arsenite. HaCaT keratinocytes and ex vivo human skin were exposed to 2μM sodium arsenite and low dose (2J/cm2) solar-simulated UV, with and without nicotinamide supplementation. DNA photolesions in the form of 8-oxo-7,8-dihydro-2′-deoxyguanosine and cyclobutane pyrimidine dimers were detected by immunofluorescence. Arsenic exposure significantly increased levels of 8-oxo-7,8-dihydro-2′-deoxyguanosine in irradiated cells. Nicotinamide reduced both types of photolesions in HaCaT keratinocytes and in ex vivo human skin, likely by enhancing DNA repair. These results demonstrate a reduction of two different photolesions over time in two different models in UV and arsenic exposed cells. Nicotinamide is a nontoxic, inexpensive agent with potential for chemoprevention of arsenic induced skin cancer. 相似文献
999.
BackgroundInnovative physical activity monitoring technology can be used to depict rich visual feedback that encompasses the various aspects of physical activity known to be important for health. However, it is unknown whether patients who are at risk of chronic disease would understand such sophisticated personalised feedback or whether they would find it useful and motivating. The purpose of the present study was to determine whether technology-enabled multidimensional physical activity graphics and visualisations are comprehensible and usable for patients at risk of chronic disease.MethodWe developed several iterations of graphics depicting minute-by-minute activity patterns and integrated physical activity health targets. Subsequently, patients at moderate/high risk of chronic disease (n=29) and healthcare practitioners (n=15) from South West England underwent full 7-days activity monitoring followed by individual semi-structured interviews in which they were asked to comment on their own personalised visual feedback Framework analysis was used to gauge their interpretation and of personalised feedback, graphics and visualisations.ResultsWe identified two main components focussing on (a) the interpretation of feedback designs and data and (b) the impact of personalised visual physical activity feedback on facilitation of health behaviour change. Participants demonstrated a clear ability to understand the sophisticated personal information plus an enhanced physical activity knowledge. They reported that receiving multidimensional feedback was motivating and could be usefully applied to facilitate their efforts in becoming more physically active.ConclusionMultidimensional physical activity feedback can be made comprehensible, informative and motivational by using appropriate graphics and visualisations. There is an opportunity to exploit the full potential created by technological innovation and provide sophisticated personalised physical activity feedback as an adjunct to support behaviour change. 相似文献
1000.
Ole A. Andreassen Rahul S. Desikan Yunpeng Wang Wesley K. Thompson Andrew J. Schork Verena Zuber Nadezhda T. Doncheva Eva Ellinghaus Mario Albrecht Morten Mattingsdal Andre Franke Benedicte A. Lie Ian G. Mills P?l Aukrust Linda K. McEvoy Srdjan Djurovic Tom H. Karlsen Anders M. Dale 《PloS one》2015,10(5)