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991.
Plant and Soil - Root residues are an important factor influencing soil phosphorus (P) availability for crop uptake, but how the residues from different species combinations in sole cropping or...  相似文献   
992.
Chuck-will's-widow (Antrostomus carolinensis) and eastern whip-poor-will (Antrostomus vociferus) are nightjars in eastern North America that have declined 69% and 67%, respectively, in abundance since 1966, resulting in conservation concerns for these species. We investigated relationships between nightjar abundance and landscape composition, forest structure, and application of tree thinning and prescribed fire because of regional interest in woodland restoration and nightjar conservation. We conducted nocturnal nightjar surveys at 385 points in southern Missouri, USA, in 2014 and 2015 and related counts to pine (Pinus spp.) and hardwood basal area, canopy closure, percent forest cover, and percent of area thinned or burned within 500 m of survey points. We modeled abundance of chuck-will's-widow and eastern whip-poor-will using time-removal models that included a detection process and an abundance process within a hierarchical Bayesian framework. We detected 534 eastern whip-poor-will and 186 chuck-will's-widow during surveys. Our data supported global models that included all 6 vegetation and management variables for both species. Chuck-will's-widow abundance was negatively related to hardwood basal area and peaked at intermediate values of percent area burned and percent forest cover. Eastern whip-poor-will abundance was negatively related to hardwood basal area and canopy cover, positively related to percent forest cover and percent of area burned, and peaked at low to moderate levels of percent of area thinned. Relationships to forest structure and management activities generally supported the conclusion that woodland restoration benefits nightjars and that chuck-will's-widow select landscapes with less forest cover than eastern whip-poor-will.  相似文献   
993.
Microbiology - The strain of facultative chemolithotrophic bacteria isolated from soil within the aphotic zone of the Kinderlinskaya Cave (Southern Urals, Russia) was identified as member of the...  相似文献   
994.
Evolutionary Ecology - Understanding how environmental drivers induce changes in plant composition and diversity across evolutionary time can provide important insights into community assembly...  相似文献   
995.
Human Physiology - The effect of 20-minute transcutaneous electrical spinal cord stimulation (tESCS) on the severity of nonreciprocal and recurrent inhibition of spinal α-motoneurons in humans...  相似文献   
996.
Environmental Biology of Fishes - Mating systems in fishes are extremely diverse, ranging from monogamy to multiple polygamous forms, some of which include alternative male mating tactics within...  相似文献   
997.
Cellular and Molecular Neurobiology - Organelles juxtaposition has been detected for decades, although only recently gained importance due to a pivotal role in the regulation of cellular processes...  相似文献   
998.
Shariati  S.  Ebenau-Jehle  C.  Pourbabaee  A. A.  Alikhani  H. A.  Rodriguez-Franco  M.  Agne  M.  Jacoby  M.  Geiger  R.  Shariati  F.  Boll  M. 《Biodegradation》2022,33(1):59-70
Biodegradation - Phthalic acid esters are predominantly used as plasticizers and are industrially produced on the million ton scale per year. They exhibit endocrine-disrupting, carcinogenic,...  相似文献   
999.
Calbindin-D28k is a calcium binding protein that is highly expressed in the mammalian central nervous system. It has been reported that calbindin-D28k binds to and increases the activity of inositol Monophosphatase (IMPase). This is an enzyme that is involved in the homeostasis of the Inositol trisphosphate signalling cascade by catalysing the final dephosphorylation of inositol and has been implicated in the therapeutic mechanism of lithium treatment of bipolar disorder. Previously studies have shown that calbindin-D28k can increase IMPase activity by up to 250 hundred-fold. A preliminary in silico model was proposed for the interaction.Here, we aimed at exploring the shape and properties of the calbindin-IMPase complex to gain new insights on this biologically important interaction. We created several fusion constructs of calbindin-D28k and IMPase, connected by flexible amino acid linkers of different lengths and orientations to fuse the termini of the two proteins together. The resulting fusion proteins have activities 200%–400% higher the isolated wild-type IMPase. The constructs were characterized by small angle X-ray scattering to gain information on the overall shape of the complexes and validate the previous model. The fusion proteins form a V-shaped, elongated and less compact complex as compared to the model. Our results shed new light into this protein-protein interaction.  相似文献   
1000.
He  Fang  Liu  Yuan  Li  Pan  Wu  Xiaoyan  Xia  Yaoyao  Zhang  Dong  Li  Nengzhang  Peng  Yuanyi  Zhu  Guoqiang  Hardeland  Rüdiger  Reiter  Russel J.  Ren  Wenkai 《中国科学:生命科学英文版》2022,65(7):1430-1444

Bacterial infections caused by Gram-negative pathogens represent a growing burden for public health worldwide. Despite the urgent need for new antibiotics that effectively fight against pathogenic bacteria, very few compounds are currently under development or approved in the clinical setting. Repurposing compounds for other uses offers a productive strategy for the development of new antibiotics. Here we report that the multifaceted melatonin effectively improves survival rates of mice and decreases bacterial loads in the lung during infection. Mechanistically, melatonin specifically inhibits the activity of citrate synthase of Gram-negative pathogens through directly binding to the R300, D363, and H265 sites, particularly for the notorious Pasteurella multocida. These findings highlight that usage of melatonin is a feasible and alternative therapy to tackle the increasing threat of Gram-negative pathogen infections via disrupting metabolic flux of bacteria.

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