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On the potential of documenting decadal-scale avifaunal change from before-and-after comparisons of museum and observational data across North America
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作者 Fernando Machado-Stredel Benedictus Freeman +12 位作者 Daniel Jiménez-Garcia Marlon E.Cobos Claudia Nunez-Penichet Laura Jiménez Ed Komp Utku Perktas Ali Khalighifar Kate Ingenloff Walter Tapondjou Thilina de Silva Sumudu Fernando Luis Osorio-Olvera A.Townsend Peterson 《Avian Research》 SCIE CSCD 2022年第1期1-10,共10页
Studies of biodiversity dynamics have been cast on either long(systematics)or short(ecology)time scales,leaving a gap in coverage for moderate time scales of decades to centuries.Large-scale biodiversity information r... Studies of biodiversity dynamics have been cast on either long(systematics)or short(ecology)time scales,leaving a gap in coverage for moderate time scales of decades to centuries.Large-scale biodiversity information resources now available offer opportunities to fill this gap for many parts of the world via detailed,quantitative comparisons of assemblage composition,particularly for regions without rich time series datasets.We explore the possibility that such changes in avifaunas across the United States and Canada before and after the first three decades of marked global change(i.e.,prior to 1980 versus after 2010)can be reconstructed and characterized from existing primary biodiversity data.As an illustration of the potential of this methodology for sites even in regions not as well sampled as the United States and Canada,we also explored changes at a single site in Mexico(Chichén-Itzá).We analyzed two large-scale datasets:one summarizing bird records in the United States and Canada before 1980,and one for the same region after 2010.We used probabilistic inventory completeness analyses to identify sites that have avifaunas that have likely been inventoried more or less completely.We prepared detailed comparisons between the two time periods to analyze species showing distributional changes over the time period analyzed.We identified 139 sites on a 0.05°grid that were demonstrably well-inventoried before 1980 in the United States and Canada,of which 108 were also well-inventoried after 2010.Comparing presence/absence patterns between the two time periods for 601 bird species,we found significant spatial autocorrelation in overall avifaunal turnover(species gained and lost),but not in numbers of species lost.We noted potential northward retractions of ranges of several species with high-latitude(boreal)distributions,while other species showed dominant patterns of population loss,either rangewide(e.g.,Tympanuchus cupido)or regionally(e.g.,Thryomanes bewickii).We developed linear models to explore a suite of potential drivers of species loss at relatively fine-grained resolutions(<6km),finding significant effects of precipitation increase,particularly on the eastern border of the United States and Canada.Our exploration of biotic change in Chichén-Itzáincluded 265 species and showed intriguing losses from the local avifauna(e.g.,Patagioenas speciosa),as well as vagrant and recent invasive species in the Yucatán Peninsula.The present work documents both the potential for and the problems involved in an approach integrating primary biodiversity data across time periods.This method potentially allows researchers to assess intermediate-time-scale biodiversity dynamics that can reveal patterns of change in biodiversity-rich regions that lack extensive time-series information. 展开更多
关键词 Biodiversity dynamics BIRDS Climate change Inventory completeness Time scale TURNOVER
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Grape Seed Extract (<i>Vitisvinifera</i>) Alleviate Neurotoxicity and Hepatotoxicity Induced by Lead Acetate in Male Albino Rats 被引量:1
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作者 Abeer M. Waggas 《Journal of Behavioral and Brain Science》 2012年第2期176-184,共9页
Grape seed extracts (GSE) are very potent antioxidant and exhibit numerous interesting pharmacologic activities, including an antioxidant property, and has been suggested to be of use in treatment of several diseases.... Grape seed extracts (GSE) are very potent antioxidant and exhibit numerous interesting pharmacologic activities, including an antioxidant property, and has been suggested to be of use in treatment of several diseases. The present study has been undertaken to investigate the protective and therapeutic effect of GSE against lead-induced neuro and hepatotoxicity in rat. Male albino rats were divided into six groups: the 1st group, rats were injected daily with saline vehicle and served as negative control, the 2nd group (positive control group), the rats were injected (i.p.) with subacute dose (100 mg/kg b·w/day) of lead acetate (LA). The 3rd group (protective group), the rats were injected (i.p.) with LA (100 mg/kg b·w/day) for 7 days after treatment with GSE (100 mg/kg b·w/day) for 3 weeks. The 4th, 5th and 6th groups (therapeutics groups), rats were injected (i.p.) with subacut dose (100 mg/kg b·w/day) of lead acetate for 7 days, then treated with GSE (100 mg/kg b·w/day) for one, two and three weeks, respectively. The level of norepinephrine (NE), dopamine (DA), serotonin (5-HT) and 5-hydroxyindol acetic acid (5-HIAA) were evaluated in brain regions (cerebellum, brainstem, striatum, cerebral cortex, hypothalamus and hippocampus). The result indicated that the administration of subacute dose of LA (100 mg/kg/day, i.p.) induce a significant decrease in NE, DA, 5-HT and 5-HIAA content in all tested brain regions. Also the obtained data showed significant increase in liver enzymes: serum glutamate oxaloacetate transaminase (GOT), serum glutamate pyruvate transaminase (GPT) and Lactate dehydrogenase (LDH) level in group 2 (positive control). There is an improvement in neurotransmitters content. Also the obtained data showed significant in- crease in liver enzymes of protective (G3) and therapeutics groups (G4, G5 and G6) which received GSE compared with animal group that received lead acetate (G2). This is may be the presence of proanthocyanidins and procyanidins which have antioxidant and free radical scavenging activities. The result suggests that grape seed extract may prevent lead-induced neurotoxicity and hepatotoxicity. 展开更多
关键词 Grape Seed Extract LEAD LEAD Acetate Antioxidant NOREPINEPHRINE Dopamine Serotonin 5-Hydroxyindol Acetic Acid Brain Liver Rat
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