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1.
Glob Chang Biol ; 23(3): 1258-1281, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27387228

RESUMO

A potato crop multimodel assessment was conducted to quantify variation among models and evaluate responses to climate change. Nine modeling groups simulated agronomic and climatic responses at low-input (Chinoli, Bolivia and Gisozi, Burundi)- and high-input (Jyndevad, Denmark and Washington, United States) management sites. Two calibration stages were explored, partial (P1), where experimental dry matter data were not provided, and full (P2). The median model ensemble response outperformed any single model in terms of replicating observed yield across all locations. Uncertainty in simulated yield decreased from 38% to 20% between P1 and P2. Model uncertainty increased with interannual variability, and predictions for all agronomic variables were significantly different from one model to another (P < 0.001). Uncertainty averaged 15% higher for low- vs. high-input sites, with larger differences observed for evapotranspiration (ET), nitrogen uptake, and water use efficiency as compared to dry matter. A minimum of five partial, or three full, calibrated models was required for an ensemble approach to keep variability below that of common field variation. Model variation was not influenced by change in carbon dioxide (C), but increased as much as 41% and 23% for yield and ET, respectively, as temperature (T) or rainfall (W) moved away from historical levels. Increases in T accounted for the highest amount of uncertainty, suggesting that methods and parameters for T sensitivity represent a considerable unknown among models. Using median model ensemble values, yield increased on average 6% per 100-ppm C, declined 4.6% per °C, and declined 2% for every 10% decrease in rainfall (for nonirrigated sites). Differences in predictions due to model representation of light utilization were significant (P < 0.01). These are the first reported results quantifying uncertainty for tuber/root crops and suggest modeling assessments of climate change impact on potato may be improved using an ensemble approach.


Assuntos
Mudança Climática , Solanum tuberosum , Biomassa , Bolívia , Dinamarca , Modelos Teóricos , Washington
2.
Arch Phys Med Rehabil ; 98(9): 1732-1743.e7, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28363702

RESUMO

OBJECTIVE: To assess the effect of an intervention designed to enhance physiotherapists' communication skills on patients' adherence to recommendations regarding home-based rehabilitation for chronic low back pain. DESIGN: Cluster randomized controlled trial. SETTING: Publicly funded physiotherapy clinics. PARTICIPANTS: A sample (N=308) of physiotherapists (n=53) and patients with chronic low back pain (n=255; 54% female patients; mean age, 45.3y). INTERVENTIONS: Patients received publicly funded individual physiotherapy care. In the control arm, care was delivered by a physiotherapist who had completed a 1-hour workshop on evidence-based chronic low back pain management. Patients in the experimental arm received care from physiotherapists who had also completed 8 hours of communication skills training. MAIN OUTCOME MEASURES: (1) Patient-reported adherence to their physiotherapists' recommendations regarding home-based rehabilitation measured at 1, 4, 12, and 24 weeks after the initial treatment session. (2) Pain and pain-related function measured at baseline and at 4, 12, and 24 weeks. RESULTS: A linear mixed model analysis revealed that the experimental arm patients' ratings of adherence were higher than those of controls (overall mean difference, .41; 95% confidence interval, .10-.72; d=.28; P=.01). Moderation analyses revealed that men, regardless of the intervention, showed improvements in pain-related function over time. Only women in the experimental arm showed functional improvements; female controls showed little change in function over time. The Communication Style and Exercise Compliance in Physiotherapy intervention did not influence patients' pain, regardless of their sex. CONCLUSIONS: Communication skills training for physiotherapists had short-term positive effects on patient adherence. This training may provide a motivational basis for behavior change and could be a useful component in complex interventions to promote adherence. Communication skills training may also improve some clinical outcomes for women, but not for men.


Assuntos
Comunicação em Saúde/métodos , Dor Lombar/psicologia , Fisioterapeutas/educação , Modalidades de Fisioterapia/psicologia , Autocuidado/psicologia , Adulto , Idoso , Dor Crônica/psicologia , Dor Crônica/reabilitação , Análise por Conglomerados , Feminino , Humanos , Dor Lombar/reabilitação , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Relações Profissional-Paciente , Autocuidado/métodos , Resultado do Tratamento , Adulto Jovem
3.
J Org Chem ; 80(16): 8036-45, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26204427

RESUMO

A range of new biphenylazepinium salt organocatalysts effective for asymmetric epoxidation has been developed incorporating an additional substituted oxazolidine ring, and providing improved enantiocontrol in alkene epoxidation over the parent structure. Starting from enantiomerically pure aminoalcohols, tetracyclic iminium salts were obtained as single diastereoisomers through an atroposelective oxazolidine formation.

4.
Child Dev ; 85(3): 1275-1291, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24138098

RESUMO

Considerable research has been devoted to examining the relations between self-esteem and social support. However, the exact nature and direction of these relations are not well understood. Measures of self-esteem, and social support quantity and quality were administered to 961 adolescents across five yearly time points (M(age) = 13.41 years). Structural equation modeling (SEM) was utilized to test between a self-esteem antecedent model (self-esteem precedes changes in social support), self-esteem consequence model (social support precedes change in self-esteem), and a reciprocal influence model. Self-esteem reliably predicted increasing levels of social support quality and network size across time. In contrast, the consequence model was not supported. The implications of this for helping adolescents to develop higher quality social support structures are discussed.


Assuntos
Desenvolvimento do Adolescente/fisiologia , Autoimagem , Apoio Social , Adolescente , Feminino , Humanos , Estudos Longitudinais , Masculino
5.
J Org Chem ; 77(14): 6128-38, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22708806

RESUMO

Introduction of a pseudoaxial substituent at a stereogenic center adjacent to the nitrogen atom in binaphthyl- and biphenyl-derived azepinium salt organocatalysts affords improved enantioselectivities and yields in the epoxidation of unfunctionalized alkenes. In the biphenyl-derived catalysts, the atropoisomerism at the biphenyl axis is controlled by the interaction of this substituent with the chiral substituent at nitrogen.


Assuntos
Compostos de Epóxi/síntese química , Iminas/química , Termodinâmica , Alcenos/química , Catálise , Cristalografia por Raios X , Compostos de Epóxi/química , Modelos Moleculares , Estrutura Molecular , Sais/química , Estereoisomerismo
6.
Glycoconj J ; 27(1): 89-97, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19936918

RESUMO

Inhibition of bacterial adhesion to intestinal epithelial receptors by the consumption of natural food components is an attractive strategy for the prevention of microbial related gastrointestinal illness. We hypothesised that Muc1, a highly glycosylated mucin present in cows' milk, may be one such food component. Purified bovine Muc1 was tested for its ability to inhibit binding of common enteric bacterial pathogens to Caco-2 cells grown in vitro. Muc1 caused dose-dependent binding inhibition of Escherichia coli, Salmonella enterica serovar Typhimurium (S. Typhimurium), Staphylococcus aureus and Bacillus subtilis. This inhibition was more pronounced for the Gram negative compared with Gram positive bacteria. It was also demonstrated that Muc1, immobilised on a membrane, bound all these bacterial species in a dose-dependent manner, although there was greater interaction with the Gram negative bacteria. A range of monosaccharides, representative of the Muc1 oligosaccharide composition, were tested for their ability to prevent binding of E. coli and S. Typhimurium to Caco-2 cells. Inhibition was structure dependent with sialic acid, L(-) fucose and D(+) mannose significantly inhibiting binding of both Gram negative species. N-acetylglucosamine and N-acetylgalactosamine significantly inhibited binding of E. coli whilst galactose, one of the most abundant Muc1 monosaccharides, showed the strongest inhibition against S. Typhimurium. Treatment with sialidase significantly decreased the inhibitory properties of Muc1, demonstrating the importance of sialic acid in adhesion inhibition. It is concluded that bovine Muc1 prevents binding of bacteria to human intestinal cells and may have a role in preventing the binding of common enteropathogenic bacteria to human intestinal epithelial surfaces.


Assuntos
Enterobacteriaceae/metabolismo , Mucina-1/metabolismo , Animais , Aderência Bacteriana/efeitos dos fármacos , Biotinilação/efeitos dos fármacos , Células CACO-2 , Bovinos , Eletroforese em Gel de Poliacrilamida , Enterobacteriaceae/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Proteínas Imobilizadas/metabolismo , Membranas Artificiais , Monossacarídeos/farmacologia , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase/metabolismo , Polivinil
7.
IEEE Trans Biomed Eng ; 54(4): 694-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17405376

RESUMO

Traditional acoustic speech recognition accuracies have been shown to deteriorate in highly noisy environments. A secondary information source is exploited using surface myoelectric signals (MES) collected from facial articulatory muscles during speech. Words are classified at the phoneme level using a hidden Markov model (HMM) classifier. Acoustic and MES data was collected while the words "zero" through "nine" were spoken. An acoustic expert classified the 18 formative phonemes in low noise levels [signal-to-noise ratio (SNR) of 17.5 dB] with an accuracy of 99%, but deteriorated to approximately 38% under simulations with SNR approaching 0 dB. A fused acoustic-myoelectric multiexpert system, without knowledge of SNR, improved on acoustic classification results at all noise levels. A multiexpert system, incorporating SNR information, obtained accuracies of 99% at low noise levels while maintaining accuracies above 94% during low SNR (0 dB) simulations. Results improve on previous full word MES speech recognition accuracies by almost 10%.


Assuntos
Eletromiografia/métodos , Músculos Faciais/fisiologia , Contração Muscular/fisiologia , Reconhecimento Automatizado de Padrão/métodos , Medida da Produção da Fala/métodos , Interface para o Reconhecimento da Fala , Fala/fisiologia , Algoritmos , Sistemas Inteligentes , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
PLoS One ; 12(8): e0181954, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28763471

RESUMO

In agricultural production, land-use decisions are components of economic planning that result in the strategic allocation of fields. Climate variability represents an uncertainty factor in crop production. Considering yield impact, climatic influence is perceived during and evaluated at the end of crop production cycles. In practice, this information is then incorporated into planning for the upcoming season. This process contributes to attitudes toward climate-induced risk in crop production. In the literature, however, the subjective valuation of risk is modeled as a risk attitude toward variations in (monetary) outcomes. Consequently, climatic influence may be obscured by political and market influences so that risk perceptions during the production process are neglected. We present a utility concept that allows the inclusion of annual risk scores based on mid-season risk perceptions that are incorporated into field-planning decisions. This approach is exemplified and implemented for winter wheat production in the Kraichgau, a region in Southwest Germany, using the integrated bio-economic simulation model FarmActor and empirical data from the region. Survey results indicate that a profitability threshold for this crop, the level of "still-good yield" (sgy), is 69 dt ha-1 (regional mean Kraichgau sample) for a given season. This threshold governs the monitoring process and risk estimators. We tested the modeled estimators against simulation results using ten projected future weather time series for winter wheat production. The mid-season estimators generally proved to be effective. This approach can be used to improve the modeling of planning decisions by providing a more comprehensive evaluation of field-crop response to climatic changes from an economic risk point of view. The methodology further provides economic insight in an agrometeorological context where prices for crops or inputs are lacking, but farmer attitudes toward risk should still be included in the analysis.


Assuntos
Agricultura/métodos , Clima , Produtos Agrícolas/fisiologia , Algoritmos , Mudança Climática , Simulação por Computador , Tomada de Decisões , Alemanha , Modelos Econômicos , Modelos Estatísticos , Risco , Estações do Ano , Tempo (Meteorologia)
9.
Neuron ; 87(5): 999-1007, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26299474

RESUMO

The mammalian neocortex is composed of two major neuronal cell types with distinct origins: excitatory pyramidal neurons and inhibitory interneurons, generated in dorsal and ventral progenitor zones of the embryonic telencephalon, respectively. Thus, inhibitory neurons migrate relatively long distances to reach their destination in the developing forebrain. The role of lineage in the organization and circuitry of interneurons is still not well understood. Utilizing a combination of genetics, retroviral fate mapping, and lineage-specific retroviral barcode labeling, we find that clonally related interneurons can be widely dispersed while unrelated interneurons can be closely clustered. These data suggest that migratory mechanisms related to the clustering of interneurons occur largely independent of their clonal origin.


Assuntos
Movimento Celular/fisiologia , Interneurônios/fisiologia , Rede Nervosa/fisiologia , Inibição Neural , Células-Tronco Neurais/fisiologia , Telencéfalo/citologia , Animais , Linhagem da Célula , Células Cultivadas , Córtex Cerebral/citologia , Embrião de Mamíferos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Técnicas In Vitro , Microdissecção e Captura a Laser , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/classificação , Técnicas de Cultura de Órgãos , Telencéfalo/embriologia , Transdução Genética
10.
Artigo em Inglês | MEDLINE | ID: mdl-23366147

RESUMO

This work studies the simultaneous and proportional myoelectric force and position estimation of multiple degrees of freedom (DOFs) for unilateral transradial amputees. Two experiments were conducted to compare force and position control paradigms. In the first, a force experiment, subjects performed isometric contractions, while the force applied by the limb and EMG were recorded. In the second, a position experiment, dynamic contractions were permitted during which position of the limb and EMG were measured. Artificial neural networks (ANNs) were trained to estimate force/position from EMG of the contralateral limb during mirrored bilateral contractions. This study involved contractions with combined activations of three DOFs including wrist: flexion/extension, radial/ulnar deviation and forearm supination/pronation. For the given data set, while force estimation demonstrated high accuracy (R(2)=0.84±0.02), position estimation performance was relatively poor (R(2)=0.57±0.05). Two healthy subjects participated in this work.


Assuntos
Eletromiografia/instrumentação , Eletromiografia/métodos , Redes Neurais de Computação , Próteses e Implantes , Amputados/reabilitação , Análise de Variância , Eletrodos , Humanos , Fenômenos Mecânicos , Reconhecimento Automatizado de Padrão , Tecnologia Assistiva , Processamento de Sinais Assistido por Computador , Punho/fisiologia
11.
Blood ; 103(6): 2404-6, 2004 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-14615371

RESUMO

The virulence of the malaria parasite, Plasmodium falciparum, is due in large part to the way in which it modifies the membrane of its erythrocyte host. In this work we have used confocal microscopy and fluorescence recovery after photo-bleaching to examine the lateral mobility of host membrane proteins in erythrocytes infected with P falciparum at different stages of parasite growth. The erythrocyte membrane proteins band 3 and glycophorin show a marked decrease in mobility during the trophozoite stage of growth. Erythrocytes infected with a parasite strain that does not express the knob-associated histidine-rich protein show similar effects, indicating that this parasite protein does not contribute to the immobilization of the host proteins. Erythrocytes infected with ring-stage parasites exhibit intermediate mobility indicating that the parasite is able to modify its host prior to its active feeding stage.


Assuntos
Membrana Eritrocítica/parasitologia , Interações Hospedeiro-Parasita , Malária Falciparum/parasitologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/fisiologia , Animais , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Membrana Eritrocítica/metabolismo , Recuperação de Fluorescência Após Fotodegradação , Glicoforinas/metabolismo , Humanos , Malária Falciparum/metabolismo , Fluidez de Membrana/fisiologia
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