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431.
Understanding the nature of the interactions between humans and wildlife is of vital importance for conflict mitigation. We equipped five leopards with GPS-collars in Maharashtra (4) and Himachal Pradesh (1), India, to study movement patterns in human-dominated landscapes outside protected areas. An adult male and an adult female were both translocated 52 km, and exhibited extensive, and directional, post release movements (straight line movements: male = 89 km in 37 days, female = 45 km in 5 months), until they settled in home ranges of 42 km2 (male) and 65 km2 (female). The three other leopards, two adult females and a young male were released close to their capture sites and used small home ranges of 8 km2 (male), 11 km2 and 15 km2 (females). Movement patterns were markedly nocturnal, with hourly step lengths averaging 339±9.5 m (SE) during night and 60±4.1 m during day, and night locations were significantly closer to human settlements than day locations. However, more nocturnal movements were observed among those three living in the areas with high human population densities. These visited houses regularly at nighttime (20% of locations <25 m from houses), but rarely during day (<1%). One leopard living in a sparsely populated area avoided human settlements both day and night. The small home ranges of the leopards indicate that anthropogenic food resources may be plentiful although wild prey is absent. The study provides clear insights into the ability of leopards to live and move in landscapes that are extremely modified by human activity. 相似文献
432.
Vidya Nand Ravi Das Ravindra Nath Pandey Krishna Pandey Varsha Singh Vijay Kumar Greg Matlashewski Pradeep Das 《PLoS neglected tropical diseases》2014,8(5)
Background
One of the major challenges for management of visceral leishmaniasis (VL) is early diagnosis of cases to improve treatment outcome and reduce transmission. We have therefore investigated active case detection of VL with the help of accredited social health activists (ASHA). ASHAs are women who live in the community and receive performance-based incentives for overseeing maternal and other health-related issues in their village.Methods and Principal Finding
Through conducting interviews with 400 randomly selected ASHAs from four primary health care centers (PHCs), it was observed that their level of knowledge about visceral leishmaniasis (VL) regarding transmission, diagnosis, and treatment was limited. The baseline data indicated that less than 10% of VL cases seeking treatment at the PHCs were referred by ASHAs. To increase the knowledge and the referral rate of VL cases by ASHAs, training sessions were carried out during the monthly ASHA meetings at their respective PHCs. Following a single training session, the referral rate increased from less than 10% to over 27% and the overall knowledge about VL substantially improved. It was not possible, however, to demonstrate that ASHA training reduced the time that individuals had fever before treatment at the PHC.Conclusions
Training ASHAs to identify VL cases in villages for early diagnosis and treatment at the local PHC is feasible and should be undertaken routinely to improve knowledge about VL. 相似文献433.
Marc U. Baumann Henning Schneider Antoine Malek Vidya Palta Daniel V. Surbek Ruth Sager Stacy Zamudio Nicholas P. Illsley 《PloS one》2014,9(8)
Glucose transport to the fetus across the placenta takes place via glucose transporters in the opposing faces of the barrier layer, the microvillous and basal membranes of the syncytiotrophoblast. While basal membrane content of the GLUT1 glucose transporter appears to be the rate-limiting step in transplacental transport, the factors regulating transporter expression and activity are largely unknown. In view of the many studies showing an association between IGF-I and fetal growth, we investigated the effects of IGF-I on placental glucose transport and GLUT1 transporter expression. Treatment of BeWo choriocarcinoma cells with IGF-I increased cellular GLUT1 protein. There was increased basolateral (but not microvillous) uptake of glucose and increased transepithelial transport of glucose across the BeWo monolayer. Primary syncytial cells treated with IGF-I also demonstrated an increase in GLUT1 protein. Term placental explants treated with IGF-I showed an increase in syncytial basal membrane GLUT1 but microvillous membrane GLUT1 was not affected. The placental dual perfusion model was used to assess the effects of fetally perfused IGF-I on transplacental glucose transport and syncytial GLUT1 content. In control perfusions there was a decrease in transplacental glucose transport over the course of the perfusion, whereas in tissues perfused with IGF-I through the fetal circulation there was no change. Syncytial basal membranes from IGF-I perfused tissues showed an increase in GLUT1 content. These results demonstrate that IGF-I, whether acting via microvillous or basal membrane receptors, increases the basal membrane content of GLUT1 and up-regulates basal membrane transport of glucose, leading to increased transepithelial glucose transport. These observations provide a partial explanation for the mechanism by which IGF-I controls nutrient supply in the regulation of fetal growth. 相似文献
434.
435.
Genetic variation, haplotype relationships, and potential regions of diversity in Symplocos laurina Wall. (Symplocaceae), a montane tree species from India, have been tested using molecular and biogeographical data to infer
phylogeographic patterns. The polymerase chain reaction-restriction fragment length polymorphism technique was used to determine
the chloroplast (cp) and mitochondrial (mt) DNA haplotypes of 218 individuals from 12 populations, collected from Northeast
India (NEI), which is a part of Indo-Burma biodiversity hotspot, and South India, which includes the Western Ghats (WG), another
biodiversity hotspot from India and Eastern Ghats (EG). Nine cpDNA (chlorotypes) and 24 mtDNA haplotypes (mitotypes) were
identified; the WG region was identified as the most diverse for chlorotypes and the NEI region for mitotypes. Although a
strong population differentiation was observed, phylogeographic structure was found to be absent for both the genomes. The
haplotype network revealed the presence of two main lineages: NEI-WG lineage and EG lineage, largely without overlapping distributions.
The study tests two hypotheses, namely vicariance and dispersal, to understand the distribution of plants in India. The population
structure of S. laurina strongly suggests the persistence of the species in putative refugial areas preglaciation and further establishment of other
populations of S. laurina from these refugial populations. 相似文献
436.
Primary protein-digestion in Lepidopteran larvae relies on serine proteases like trypsin and chymotrypsin. Efforts toward
the classification and characterization of digestive proteases have unraveled a considerable diversity in the specificity
and mechanistic classes of gut proteases. Though the evolutionary significance of mutations that lead to structural diversity
in serine proteases has been well characterized, detailing the resultant functional diversity has continually posed a challenge
to researchers. Functional diversity can be correlated to the adaptation of insects to various host-plants as well as to exposure
of insects to naturally occurring antagonistic biomolecules such as plant-derived protease inhibitors (PIs) and lectins. Current
research is focused on deciphering the changes in protease specificities and activities arising from altered amino acids at
the active site, specificity-determining pockets and other regions, which influence activity. Some insight has been gained
through in silico modeling and simulation experiments, aided by the limited availability of characterized proteases. We examine the structurally
and functionally diverse Lepidopteran serine proteases, and assess their influence on larval digestive processes and on overall
insect physiology.
Invited paper 相似文献
437.
Rueda L Vidyadharan V 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2006,3(1):72-83
Image and statistical analysis are two important stages of cDNA microarrays. Of these, gridding is necessary to accurately identify the location of each spot while extracting spot intensities from the microarray images and automating this procedure permits high-throughput analysis. Due to the deficiencies of the equipment used to print the arrays, rotations, misalignments, high contamination with noise and artifacts, and the enormous amount of data generated, solving the gridding problem by means of an automatic system is not trivial. Existing techniques to solve the automatic grid segmentation problem cover only limited aspects of this challenging problem and require the user to specify the size of the spots, the number of rows and columns in the grid, and boundary conditions. In this paper, a hill-climbing automatic gridding and spot quantification technique is proposed which takes a microarray image (or a subgrid) as input and makes no assumptions about the size of the spots, rows, and columns in the grid. The proposed method is based on a hill-climbing approach that utilizes different objective functions. The method has been found to effectively detect the grids on microarray images drawn from databases from GEO and the Stanford genomic laboratories. 相似文献
438.
Jayasankar V Jasmani S Tsutsui N Aida K Wilder MN 《Journal of experimental zoology. Part A, Comparative experimental biology》2006,305(5):440-448
The dynamics of vitellogenin (Vg) mRNA expression and patterns of Vg and vitellin distribution in the hepatopancreas and ovary of juvenile Macrobrachium rosenbergii were examined using real-time RT-PCR and immunohistochemical methods. Eyestalk ablation was seen to induce rapid development of the gonads and Vg synthesis in females. In the female hepatopancreas, Vg mRNA expression was observed several days following ablation, after which levels increased gradually with increasing gonadosomatic index (GSI). Vitellin accumulation in the oocytes also increased with increasing Vg mRNA synthesis; expression was however negligible in the ovary. Hemolymph Vg levels in females ranged from 0.04 to 2.2 mg/ml. SDS PAGE/Western blotting analysis of hemolymph samples revealed that juvenile Vg was composed of 199 and 90 kDa subunits; the 102 kDa subunit present in adult female Vg (Okuno et al., 2002. J Exp Zool 292:417-429) could not be detected at any stage of vitellogenesis in juveniles. Vg was not detectable in non-ablated juveniles. The results of this study confirmed that the mode of involvement of eyestalk factors in regulating vitellogenesis is intrinsic to both juveniles and adults, and that a basic pattern of Vg synthesis and processing is conserved. However, the fact that juveniles are not able to produce the same Vg levels observed in adult females, and do not reach high GSI levels culminating in spawning suggests that other factors and physiological conditions specific to adult females are necessary to demonstrate full reproductive ability. 相似文献
439.
Extraction of Y2O3:Cr3+ nanophosphor by eco‐friendly approach and its suitability for white light‐emitting diode applications
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J. B. Prasanna Kumar G. Ramgopal D. V. Sunitha B. Daruka Prasad H. Nagabhushana Y. S. Vidya K. S. Anantharaju S. C. Prashantha S. C. Sharma K. R. Prabhakara 《Luminescence》2017,32(3):414-424
Cr3+‐doped Y2O3 (0.5–9 mol%) was synthesized by a simple solution combustion method using Aloe vera gel as a fuel/surfactant. The final obtained product was calcined at 750°C for 3 h, which is the lowest temperature reported so far for the synthesis of this compound. The calcined product was confirmed for its crystallinity and purity by powder X‐ray diffraction (PXRD) studies which showed a single‐phase nano cubic phosphor. The particles size estimated by Scherrer formula was in the range of 6–19 nm. The UV–vis spectra showed absorption bands at 198, 272 and 372 nm having band gap energy in the range 4.00–4.26 eV. In order to investigate the possibility of its use in white light emitting display applications, the photoluminescence properties of Cr3+‐doped Y2O3 nanophosphors were studied at an excitation wavelength in the near ultraviolet (UV) light region (361 nm). The emission spectra consisted of emission peaks in the blue (4F9/2 → 6H15/2), orange (4F9/2 → 6H13/2) and red (4F9/2 → 6H11/2) regions. The CIE coordinates (0.33, 0.33) lie in the white light region. Hence Y2O3:Cr3+ can be used for white light‐emitting diode (LED) applications. 相似文献
440.