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1.
A group of captive chimpanzees, consisting of one adult male and three mother/infant pairs, was systematically observed over a 15-month period. Over 200 hr of data were collected, using both sequential and time sampling techniques, and compared to the available data on wild chimps. Unlike many captive groups, most behavior patterns were remarkably similar, both qualitatively and quantitatively, to that of wild chimpanzees including: play, grooming, infant sexual development, tool use, food sharing, prosocial partner preferences, and aggressive displays. 相似文献
2.
Shreaya Chakroborty Clark Briggs Megan B. Miller Ivan Goussakov Corinne Schneider Joyce Kim Jaime Wicks Jill C. Richardson Vincent Conklin Benjamin G. Cameransi Grace E. Stutzmann 《PloS one》2012,7(12)
Alzheimer’s disease (AD) is a devastating neurodegenerative condition with no known cure. While current therapies target late-stage amyloid formation and cholinergic tone, to date, these strategies have proven ineffective at preventing disease progression. The reasons for this may be varied, and could reflect late intervention, or, that earlier pathogenic mechanisms have been overlooked and permitted to accelerate the disease process. One such example would include synaptic pathology, the disease component strongly associated with cognitive impairment. Dysregulated Ca2+ homeostasis may be one of the critical factors driving synaptic dysfunction. One of the earliest pathophysiological indicators in mutant presenilin (PS) AD mice is increased intracellular Ca2+ signaling, predominantly through the ER-localized inositol triphosphate (IP3) and ryanodine receptors (RyR). In particular, the RyR-mediated Ca2+ upregulation within synaptic compartments is associated with altered synaptic homeostasis and network depression at early (presymptomatic) AD stages. Here, we offer an alternative approach to AD therapeutics by stabilizing early pathogenic mechanisms associated with synaptic abnormalities. We targeted the RyR as a means to prevent disease progression, and sub-chronically treated AD mouse models (4-weeks) with a novel formulation of the RyR inhibitor, dantrolene. Using 2-photon Ca2+ imaging and patch clamp recordings, we demonstrate that dantrolene treatment fully normalizes ER Ca2+ signaling within somatic and dendritic compartments in early and later-stage AD mice in hippocampal slices. Additionally, the elevated RyR2 levels in AD mice are restored to control levels with dantrolene treatment, as are synaptic transmission and synaptic plasticity. Aβ deposition within the cortex and hippocampus is also reduced in dantrolene-treated AD mice. In this study, we highlight the pivotal role of Ca2+ aberrations in AD, and propose a novel strategy to preserve synaptic function, and thereby cognitive function, in early AD patients. 相似文献
3.
Jill S. Marty James P. Higham Elizabeth L. Gadsby Caroline Ross 《International journal of primatology》2009,30(6):807-823
Sexual selection has driven the evolution and elaboration of a wide variety of displays and ornaments in male nonhuman primates,
including capes, cheek flanges, and sexual coloration. Among the most sexually dimorphic of all primates is the drill (Mandrillus leucophaeus), the males of which can be 3 times the mass of females, possess large canines, and exhibit extremely bright sexual skin
coloration. However, the function of male coloration in this species has never been examined. Here, we present data on male
color (measured objectively using digital photography), dominance rank, measures of male-female association, and key sexual
behaviors, of adult male drills (n = 17) living in four semi free-ranging enclosures at the Drill Rehabilitation and Breeding Center in Nigeria. We test the
hypothesis that male coloration is a badge of status, indicating dominance rank, and the hypothesis that male coloration attracts
females. We found that male coloration did indicate rank, and that high ranking, strongly colored males were more likely to
associate with adult females, and more specifically with fully tumescent females. These males also engaged in more sexual
activity. However, measures of male-female association and sexual behaviors were not related to male color once rank had been
taken into consideration; i.e., for males of a given rank, females did not prefer those that were more colorful. We discuss
the results in light of what is known about the wild drill social system, in which unfamiliar individuals may come together
in “supergroups,” and in which quality indicators of competitive ability may be particularly important. 相似文献
4.
Craig R. Allen Ahjond S. Garmestani Jill A. LaBram Amanda E. Peck Luanna B. Prevost 《Biological invasions》2006,8(2):169-176
Woodlots are forest islands embedded within an urban matrix, and often represent the only natural areas remaining in suburban
areas. Woodlots represent critical conservation areas for native plants, and are important habitat for wildlife in urban areas.
Invasion by non-indigenous (NIS) plants can alter ecological structure and function, and may be especially severe in remnant
forests where NIS propagule pressure is high. Woody shrubs in the Family Berberidaceae have been well documented as invaders
of the forest–urban matrix in North America. Mahonia bealei (Berberidaceae) is a clonal shrub native to China, and is a popular ornamental in the Southeastern United States. Mahoni bealei is listed as “present” on some local and state floras, but almost nothing is known regarding its invasion potential in the
United States. We sampled 15 woodlots in Clemson, South Carolina, to assess the invasion of M. bealei and other woody non-indigenous species (NIS). M. bealei invaded 87% of the woodlots surveyed and species richness of NIS on these woodlots varied from 5 to 14. Stepwise-multiple
regression indicated that less canopy cover and older M. bealei predicted greater abundance of M. bealei , and that not all subdivisions were equally invaded (P < 0.0001; r2 = 0.88). The impact of M. bealei on native flora and fauna may be considerable, and it is likely to continue to spread in the Southeastern United States.
M. bealei should be recognized as an aggressive invader in the Southeastern United States, with the potential for negative impacts
on native flora and fauna. 相似文献
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7.
Hurricane risk characteristics are examined across the U. S. Gulf of Mexico coastline using a hexagonal tessellation. Using an extreme value model, parameters are collected representing the rate or λ (frequency), the scale or σ (range), and the shape or ξ (intensity) of the extreme wind distribution. These latent parameters and the 30-year return level are visualized across the grid. The greatest 30-year return levels are located toward the center of the Gulf of Mexico, and for inland locations, along the borders of Louisiana, Mississippi, and Alabama. Using a geographically weighted regression model, the relationship of these parameters to sea surface temperature (SST) is found to assess sensitivity to change. It is shown that as SSTs increase near the coast, the frequency of hurricanes in these grids decrease significantly. This reinforces the importance of SST in areas of likely tropical cyclogenesis in determining the number of hurricanes near the coast, along with SSTs along the lifespan of the storm, rather than simply local SST. The range of hurricane wind speeds experienced near Florida is shown to increase with increasing SSTs (insignificant), suggesting that increased temperatures may allow hurricanes to maintain their strength as they pass over the Florida peninsula. The modifiable areal unit problem is assessed using multiple grid sizes. Moran’s I and the local statistic G are calculated to examine spatial autocorrelation in the parameters. This research opens up future questions regarding rapid intensification and decay close to the coast and the relationship to changing SSTs. 相似文献
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9.
Apolipoprotein E has key functions in lipoprotein metabolism, and polymorphisms in the apolipoprotein E gene are associated with distinct lipoprotein patterns. The possibility of gene-nutrient interactions for apolipoprotein E has been addressed in many studies. Although results have generally been mixed, the indications for such an interaction have been more common in studies employing a metabolic challenge. Studies directly designed to examine apolipoprotein E gene-nutrient interactions are needed. 相似文献
10.
Penicillium citrinum cultures have been germinated on an H2O-based medium, resuspended on a D2O-based medium and treated with [l,2-13C2] acetate. The resulting citrinin (1) has been analysed by2H and13C nuclear magnetic resonance spectroscopy and information about the metabolism of hydrogen in citrinin biosynthesis has been deduced. 相似文献