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51.
John A. Schneider Rakhi Dandona Shravani Pasupneti Vemu Lakshmi Chuanhong Liao Vijay Yeldandi Kenneth H. Mayer 《PloS one》2010,5(7)
Studies of HIV prevention interventions such as pre-exposure prophylaxis (PREP) and circumcision in India are limited. The present study sought to investigate Indian truck-drivers initial commitment to PREP and circumcision utilizing the AIDS Risk Reduction Model. Ninety truck-drivers completed an in-depth qualitative interview and provided a blood sample for HIV and HSV-2 testing. Truck-drivers exhibited low levels of initial commitment towards PREP and even lower for circumcision. However, potential leverage points for increasing commitment were realized in fear of infecting family rather than self, self-perceptions of risk, and for PREP focusing on cultural beliefs towards medication and physicians. Cost was a major barrier to both HIV prevention interventions. Despite these barriers, our findings suggest that the ARRM may be useful in identifying several leverage points that may be used by peers, health care providers and public health field workers to enhance initial commitment to novel HIV prevention interventions in India. 相似文献
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The potential physiological impact of morphological changes in the active dendritic spines, which are believed to be associated
with altered synaptic efficacy, was investigated in a computer simulation study using the NEURON package [1]. A compartmental
model of a simplified neuron was built, which included 30 complex spines (neck, head, and active zone) and accommodating AMPA-type
synaptic inputs with alpha-function conductances. Hodgkin-Huxley type excitable membranes were inserted into the spine heads.
It was shown that arranging spines in dense clusters, as opposed to a uniformly random spine distribution, has a negligible
effect on the synaptic signal transfer (other model conditions, including synaptic input and spine density, remained unchanged).
However, if a proportion (e.g., 3–20%) of the spines partly fuse with their neighbors forming branched spines, this could
increase dramatically the cell response to the unchanged synaptic input. Results of this pilot study provide the basis for
a more detailed investigation of the relationship between the spine arrangement and synaptic function, considering dual-component
synaptic currents and mechanisms controlling ion fluxes in the dendritic compartments. 相似文献
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A recent literature review of commentaries and ‘state of the art’ articles from researchers in psychiatric genetics (PMG)
offers a consensus about progress in the science of genetics, disappointments in the discovery of new and effective treatments,
and a general optimism about the future of the field. I argue that optimism for the field of psychiatric molecular genetics
(PMG) is overwrought, and consider progress in the field in reference to a sample estimate of US National Institute of Mental
Health funding for this paradigm for the years 2008 and 2009. I conclude that the amounts of financial investment in PMG is
questionable from an ethical perspective, given other research and clinical needs in the USA. 相似文献
56.
John M. Miller 《BMJ (Clinical research ed.)》1889,2(1506):1063-1064
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Spencer G. Lucas Bolat U. Bayshashov Lyubov A. Tyutkova Ayzhan K. Zhamangara Bolat Z. Aubekerov 《Pal?ontologische Zeitschrift》1997,71(3-4):305-314
At Aktau Mountain in the Ili depression of eastern Kazakstan, fossil mammals that encompass the Paleogene-Neogene boundary occur at three stratigraphic levels. The lowest level is in the lower Kyzylbulak Formation and produces Brontotheriidae and the hyracodontidArdynia and is tentatively assigned a late Eocene (Ergilian) age. The lower part of the overlying Aktau Formation produces fossils of the giant rhinocerosParaceratherium and is tentatively assigned a late Oligocene (Tabenbulukian) age. The upper part of the Aktau Formation yields a fossil mammal assemblage that includesGomphotherium,Stephanocemas, Brachypotherium andLagomeryx. It is clearly of Miocene age, probably late early Miocene (late Burdigalian), a correlative of European Reference Level MN 5 and the late Shanwangian of China. The Paleogene-Neogene boundary at Aktau Mountain thus is in the Aktau Formation. 相似文献
60.
Predator detection and avoidance by starlings under differing scenarios of predation risk 总被引:3,自引:0,他引:3
Devereux Claire L.; Whittingham Mark J.; Fernandez-Juricic Esteban; Vickery Juliet A.; Krebs John R. 《Behavioral ecology》2006,17(2):303-309
Practically all animals must find food while avoiding predators.An individual's perception of predation risk may depend on manyfactors, such as distance to refuge and group size, but it isunclear whether individuals respond to different factors ina similar manner. We tested whether flocks of foraging starlingsresponded in the same way to an increased perception of predationrisk by assessing three factors: (1) neighbor distances, (2)habitat obstruction, and (3) recent exposure to a predator.We found that in all three scenarios of increased risk, starlingsreduced their interscan intervals (food-searching bouts), whichincreased the frequency of their vigilance periods. We thenexamined how one of these factors, habitat obstruction, affectedescape speed by simulating an attack with a model predator.Starlings were slower to respond in visually obstructed habitats(long grass swards) and slower when they had their head downin obstructed habitats than when they had their head down inopen habitats. In addition, reaction times were quicker whenstarlings could employ their peripheral fields of vision. Ourresults demonstrate that different sources of increased riskcan generate similar behavioral responses within a species.The degree of visibility in the physical and social environmentaffects both the actual and perceived risk of predation. 相似文献