91 research outputs found
A Unified Model of Exclusive , and \jpsi Electroproduction
A two-component model is developed for diffractive electroproduction of
, and \jpsi, based on non-perturbative and perturbative
two-gluon exchange. This provides a common kinematical structure for
non-perturbative and perturbative effects, and allows the role of the
vector-meson vertex functions to be explored independently of the production
dynamics. A good global description of the vector-meson data is obtained.Comment: 30 pages, 35 figure
Nanorings and rods interconnected by self-assembly mimicking an artificial network of neurons
[EN] Molecular electronics based on structures ordered as neural networks emerges as the next evolutionary milestone in the construction of nanodevices with unprecedented applications. However, the straightforward formation of geometrically defined and interconnected nanostructures is crucial for the production of electronic circuitry nanoequivalents. Here we report on the molecularly fine-tuned self-assembly of tetrakis-Schiff base compounds into nanosized rings interconnected by unusually large nanorods providing a set of connections that mimic a biological network of neurons. The networks are produced through self-assembly resulting from the molecular conformation and noncovalent intermolecular interactions. These features can be easily generated on flat surfaces and in a polymeric matrix by casting from solution under ambient conditions. The structures can be used to guide the position of electron-transporting agents such as carbon nanotubes on a surface or in a polymer matrix to create electrically conducting networks that can find direct use in constructing nanoelectronic circuits.The research leading to these results has received funding from ICIQ, ICREA, the Spanish Ministerio de Economia y Competitividad (MINECO) through project CTQ2011-27385 and the European Community Seventh Framework Program (FP7-PEOPLE-ITN-2008, CONTACT consortium) under grant agreement number 238363. We acknowledge E. C. Escudero-Adan, M. Martinez-Belmonte and E. Martin from the X-ray department of ICIQ for crystallographic analysis, and M. Moncusi, N. Argany, R. Marimon, M. Stefanova and L. Vojkuvka from the Servei de Recursos Cientifics i Tecnics from Universitat Rovira i Virgili (Tarragona, Spain).Escarcega-Bobadilla, MV.; Zelada-Guillen, GA.; Pyrlin, SV.; Wegrzyn, M.; Ramos, MMD.; GimĂ©nez Torres, E.; Stewart, A.... (2013). 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Validation of a Spanish translation of the Gratitude Questionnaire (GQ-6) with a Chilean sample of adults and high schoolers
InfluĂȘncia de diferentes materiais de cobertura no conforto tĂ©rmico de instalaçÔes para frangos de corte no oeste paulista
Eating disorders in weight-related therapy (EDIT): Protocol for a systematic review with individual participant data meta-analysis of eating disorder risk in behavioural weight management
The Eating Disorders In weight-related Therapy (EDIT) Collaboration brings together data from randomised controlled trials of behavioural weight management interventions to identify individual participant risk factors and intervention strategies that contribute to eating disorder risk. We present a protocol for a systematic review and individual participant data (IPD) meta-analysis which aims to identify participants at risk of developing eating disorders, or related symptoms, during or after weight management interventions conducted in adolescents or adults with overweight or obesity. We systematically searched four databases up to March 2022 and clinical trials registries to May 2022 to identify randomised controlled trials of weight management interventions conducted in adolescents or adults with overweight or obesity that measured eating disorder risk at pre- and post-intervention or follow-up. Authors from eligible trials have been invited to share their deidentified IPD. Two IPD meta-analyses will be conducted. The first IPD meta-analysis aims to examine participant level factors associated with a change in eating disorder scores during and following a weight management intervention. To do this we will examine baseline variables that predict change in eating disorder risk within intervention arms. The second IPD meta-analysis aims to assess whether there are participant level factors that predict whether participation in an intervention is more or less likely than no intervention to lead to a change in eating disorder risk. To do this, we will examine if there are differences in predictors of eating disorder risk between intervention and no-treatment control arms. The primary outcome will be a standardised mean difference in global eating disorder score from baseline to immediately post-intervention and at 6- and 12- months follow-up. Identifying participant level risk factors predicting eating disorder risk will inform screening and monitoring protocols to allow early identification and intervention for those at risk
Eating disorders in weight-related therapy (EDIT): protocol for a systematic review with individual participant data meta-analysis of eating disorder risk in behavioural weight management
The Eating Disorders In weight-related Therapy (EDIT) Collaboration brings together data from randomised controlled trials of behavioural weight management interventions to identify individual participant risk factors and intervention strategies that contribute to eating disorder risk. We present a protocol for a systematic review and individual participant data (IPD) meta-analysis which aims to identify participants at risk of developing eating disorders, or related symptoms, during or after weight management interventions conducted in adolescents or adults with overweight or obesity. We systematically searched four databases up to March 2022 and clinical trials registries to May 2022 to identify randomised controlled trials of weight management interventions conducted in adolescents or adults with overweight or obesity that measured eating disorder risk at pre- and post-intervention or follow-up. Authors from eligible trials have been invited to share their deidentified IPD. Two IPD meta-analyses will be conducted. The first IPD meta-analysis aims to examine participant level factors associated with a change in eating disorder scores during and following a weight management intervention. To do this we will examine baseline variables that predict change in eating disorder risk within intervention arms. The second IPD meta-analysis aims to assess whether there are participant level factors that predict whether participation in an intervention is more or less likely than no intervention to lead to a change in eating disorder risk. To do this, we will examine if there are differences in predictors of eating disorder risk between intervention and no-treatment control arms. The primary outcome will be a standardised mean difference in global eating disorder score from baseline to immediately post-intervention and at 6- and 12- months follow-up. Identifying participant level risk factors predicting eating disorder risk will inform screening and monitoring protocols to allow early identification and intervention for those at risk
Distributions of calcium in A and I bands of skinned vertebrate muscle fibers stretched to beyond filament overlap.
Measurements were made of the distributions of total calcium along the length of A and I bands in skinned frog semitendinosus muscles using electron probe x-ray microanalysis. Since calcium in the water space was kept below the detection limit of the technique, the signal was assumed to reflect the distribution of calcium bound to myofilament proteins. Data from sarcomeres with overlap between thick and thin filaments showed enhancement of calcium in this region, as previously demonstrated in rabbit psoas muscle fibers in rigor (Cantino, M. E., T. S. Allen, and A. M. Gordon. 1993. Subsarcomeric distribution of calcium in demembranated fibers of rabbit psoas muscle. Biophys. J. 64:211-222). Such enhancement could arise from intrinsic non-uniformities in calcium binding to either thick or thin filaments or from enhancement of calcium binding to either filament by rigor cross-bridge attachment. To test for intrinsic variations in calcium binding, calcium distributions were determined in fibers stretched to beyond filament overlap. Calcium binding was found to be relatively uniform along both thick and thin filaments, and therefore cannot account for the increased calcium observed in the overlap region. From these results it can be concluded that the observed enhancement of calcium is due to an increase in calcium binding to myofilaments as a result of rigor attachment of cross-bridges to actin. The source of the enhancement is most likely an increase in calcium binding to troponin, although enhancement of calcium binding to myosin light chains cannot be ruled out
Measuring the Temperature Width of a First-Order Single Crystal to Single Crystal Phase Transition Using Solid-State NMR:Â Application to the Polymorphism of 2-(2,4-Dinitrobenzyl)-3-methylpyridine
Site-Selective Processes:Â The Role of Environment in the Control of Proton Transfer Processes in Crystalline Systems of 2-(2,4-Dinitrobenzyl)-3-methylpyridine
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