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1.
Sci Rep ; 14(1): 10570, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719931

RESUMO

The coexistence of sympatric species with similar ecological niches has been a central issue in ecology. Clarifying the daily activity patterns of sympatric wild ungulates can help understand their temporal niche differentiation and the mechanisms of coexistence, providing information for their conservation. The Baotianman National Nature Reserve in northern China is rich in wild ungulates, but little is known about the daily activity patterns of wild ungulates in the area, making it difficult to develop effective conservation strategies. We studied five representative wild ungulates (i.e. forest musk deer, Chinese goral, Reeve's muntjac, Siberian roe deer, and wild boar) of the region using camera-trapping data, focusing on the seasonal daily activity patterns and effects of seasonal grazing of domestic sheep, to reveal their coexistence based on temporal ecological niche differentiation. Comparative analyses of the seasonal daily activity showed that forest musk deer exhibited a single-peak activity in the warm season. Other ungulates exhibited multipeak activity. All five ungulates differed significantly in daily activity patterns. Notably, wild boar and Reeve's muntjac showed high overlap coefficients between the cold and warm seasons. In both cold and warm seasons, the five wild ungulates and domestic sheep displayed low overlap in their daily activity rhythms potentially indicating temporal ecological niche differentiation. The results suggest that temporal isolation might be a strategy for wild ungulates to avoid domestic sheep and reduce interspecific competition, and that temporal ecological niche differentiation potentially promoted the coexistence among the studied sympatric ungulates. This understanding may provide new insights for the development of targeted conservation strategies.


Assuntos
Animais Selvagens , Cervos , Ecossistema , Estações do Ano , Simpatria , Animais , Cervos/fisiologia , Animais Selvagens/fisiologia , China , Ovinos/fisiologia
2.
Soft Matter ; 14(38): 7850-7858, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30209474

RESUMO

Rectification of interacting active particles is numerically investigated in a two-dimensional time-oscillating potential. It is found that the oscillation of the potential and the self-propulsion of active particles are two different types of nonequilibrium driving, which can induce net currents with opposite directions. For a given asymmetry of the potential, the direction of the transport is determined by the competition of the self-propulsion and the oscillation of the potential. There exists an optimal oscillating angular frequency (or self-propulsion speed) at which the average velocity takes its maximal positive or negative value. Remarkably, when the oscillation of the potential competes with the self-propulsion, the average velocity can change direction several times due to the change in the oscillating frequency. Especially, particles with different self-propulsion velocities will move in opposite directions and can be separated. Our results provide a novel and convenient method for controlling and manipulating the transport (or separation) of active particles.

3.
Zhong Xi Yi Jie He Xue Bao ; 4(6): 601-5, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17090376

RESUMO

OBJECTIVE: To investigate the effects of Tongluo Recipe (TLR), a compound Chinese herbal medicine, on experimental diabetic peripheral neuropathy in rats. METHODS: Diabetes was induced by streptozocin in rats. Eight weeks later, the diabetic rats were assigned to 3 groups according to different body weights: untreated group, low-dose TLR-treated group and high-dose TLR-treated group. Eight normal rats were assigned to normal control group. Systemic and sciatic nerve intrinsic antioxidant enzyme activities, lipid peroxide levels, hemorheology and sciatic nerve conduction velocity and ultrastructure changes were evaluated. RESULTS: Glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities were lower, and lipid peroxide levels were higher in plasma and sciatic nerve of the untreated group than those in the normal control group (P<0.05). Blood glucose and viscosity in the untreated group were higher than those in the normal control group. Sciatic nerve showed demyelination changes and decrease of conduction velocity. Vasa nervorum expanded and erythrocyte deposited in the capillary in the untreated group. TLR obviously improved sciatic nerve conduction velocity and ameliorated morphology changes, decreased blood viscosity, improved SOD and GSH-Px activities. CONCLUSION: TLR can obviously improve sciatic nerve function and ameliorate morphology changes in rats with diabetic peripheral neuropathy, probably through depleting free radical production, improving endothelial cell function and ameliorating hemorheology changes.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Neuropatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Animais , Diabetes Mellitus Experimental/complicações , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/etiologia , Hemorreologia/efeitos dos fármacos , Masculino , Microscopia Eletrônica , Condução Nervosa/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/fisiopatologia , Nervo Isquiático/ultraestrutura
4.
Yi Chuan ; 27(6): 1013-9, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16378955

RESUMO

The granule-bound starch synthase(GBSS) is encoded by the rice Wx gene, which is the major gene for control of amylase synthesis of. This paper briefly introduced the progress in regulation of rice Wx gene expression at transcriptional level and post-transcriptional level. At the same time the influence of transgene, genetic background and temperature condition on Wx gene expression in rice was discussed. Finally some urgent questions were suggested for the further study on regulation of rice Wx gene expression.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/genética , Sintase do Amido/genética , Amilose/metabolismo , Inativação Gênica , Oryza/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Temperatura , Transcrição Gênica
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