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701.
K. K. Vaas H. S. Raina R. K. Langer Shyam Sunder 《International Review of Hydrobiology》1988,73(5):547-558
The energy transfer at different trophic levels in a temperate lake ecosystem locally called Sar (lake) has been investigated. Total phytoplankton production in terms of energy fixation has been estimated at 3.2 × 106 cal m−2 y−1, out of which the fish harvest amounts to 2640 cal m−2 y−1. The conversion efficiency from phytoplankton to fish has been estimated at 0.082 %. Apart from other ecological parameters discussed in the paper, suggestions for the efficient use of other available energy from the system has been highlighted. 相似文献
702.
Anette Stauch Hans-Peter Duerr Albert Picado Bart Ostyn Shyam Sundar Suman Rijal Marleen Boelaert Jean-Claude Dujardin Martin Eichner 《PLoS neglected tropical diseases》2014,8(4)
The elimination of infectious diseases requires reducing transmission below a certain threshold. The Visceral Leishmaniasis (VL) Elimination Initiative in Southeast Asia aims to reduce the annual VL incidence rate below 1 case per 10,000 inhabitants in endemic areas by 2015 via a combination of case management and vector control. Using a previously developed VL transmission model, we investigated transmission thresholds dependent on measures reducing the sand fly density either by killing sand flies (e.g., indoor residual spraying and long-lasting insecticidal nets) or by destroying breeding sites (e.g., environmental management).Model simulations suggest that elimination of VL is possible if the sand fly density can be reduced by 67% through killing sand flies, or if the number of breeding sites can be reduced by more than 79% through measures of environmental management.These results were compared to data from two recent cluster randomised controlled trials conducted in India, Nepal and Bangladesh showing a 72% reduction in sand fly density after indoor residual spraying, a 44% and 25% reduction through the use of long-lasting insecticidal nets and a 42% reduction after environmental management.Based on model predictions, we identified the parameters within the transmission cycle of VL that predominantly determine the prospects of intervention success. We suggest further research to refine model-based predictions into the elimination of VL. 相似文献
703.
We observed a group of capped langurs for 12 mo in the Pakhui Wildlife Sanctuary, Arunachal Pradesh, India. We recorded the
time of feeding on different food plant species, food categories, and the feeding heights of monkeys in trees. Capped langurs
spent 68% of their feeding time on leaves, 16% on flowers, and 16% on fruits. Feeding on leaves was consistently high (p < 0.01) during the year, with the highest feeding in May (85%) and the lowest in January (47%). The seasonal difference in
feeding on leaves is significant (p < 0.05): it was higher in summer and during monsoon. The feeding time on flowers was maximal (35%) in March and that on fruits
and seeds was minimal (38%) in January. Langurs ate 52 plant species throughout the year. The largest number of plants (6)
were species of Moraceae, and langurs spent more feeding time (20%) on them alone. The number of plants eaten per month varied
significantly (p < 0.05). Langurs ate Gmelina arborea, Albizzia lucida, Ficus glomereta, and Makania micrantha throughout the year. They spent 44% of their feeding time in terminal canopies and their average feeding height was 30–35 m.
This is the first study to examine the feeding ecology of capped langurs and provides baseline data for the species. 相似文献
704.
705.
Shyam Kumar Sudhakar Benjamin Torben-Nielsen Erik De Schutter 《PLoS computational biology》2015,11(12)
Neurons of the cerebellar nuclei convey the final output of the cerebellum to their targets in various parts of the brain. Within the cerebellum their direct upstream connections originate from inhibitory Purkinje neurons. Purkinje neurons have a complex firing pattern of regular spikes interrupted by intermittent pauses of variable length. How can the cerebellar nucleus process this complex input pattern? In this modeling study, we investigate different forms of Purkinje neuron simple spike pause synchrony and its influence on candidate coding strategies in the cerebellar nuclei. That is, we investigate how different alignments of synchronous pauses in synthetic Purkinje neuron spike trains affect either time-locking or rate-changes in the downstream nuclei. We find that Purkinje neuron synchrony is mainly represented by changes in the firing rate of cerebellar nuclei neurons. Pause beginning synchronization produced a unique effect on nuclei neuron firing, while the effect of pause ending and pause overlapping synchronization could not be distinguished from each other. Pause beginning synchronization produced better time-locking of nuclear neurons for short length pauses. We also characterize the effect of pause length and spike jitter on the nuclear neuron firing. Additionally, we find that the rate of rebound responses in nuclear neurons after a synchronous pause is controlled by the firing rate of Purkinje neurons preceding it. 相似文献
706.
Shyam Mahabal Vijay Bhaskar Reddy Konala Murali Krishna Mamidi Mohammad Mahboob Kanafi Suniti Mishra Krupa Shankar Rajarshi Pal Ramesh Bhonde 《Cytotechnology》2016,68(4):1009-1018
Human skin has continuous self-renewal potential throughout adult life and serves as first line of defence. Its cellular components such as human epidermal keratinocytes (HEKs) and dermal mesenchymal stromal cells (DMSCs) are valuable resources for wound healing applications and cell based therapies. Here we show a simple, scalable and cost-effective method for sequential isolation and propagation of HEKs and DMSCs under defined culture conditions. Human skin biopsy samples obtained surgically were cut into fine pieces and cultured employing explant technique. Plated skin samples attached and showed outgrowth of HEKs. Gross microscopic examination displayed polygonal cells with a granular cytoplasm and H&E staining revealed archetypal HEK morphology. RT–PCR and immunocytochemistry authenticated the presence of key HEK markers including trans-membrane protein epithelial cadherin (E-cadherin), keratins and cytokeratin. After collection of HEKs by trypsin–EDTA treatment, mother explants were left intact and cultured further. Interestingly, we observed the appearance of another cell type with fibroblastic or stromal morphology which were able to grow up to 15 passages in vitro. Growth pattern, expression of cytoskeletal protein vimentin, surface proteins such as CD44, CD73, CD90, CD166 and mesodermal differentiation potential into osteocytes, adipocytes and chondrocytes confirmed their bonafide mesenchymal stem cell like status. These findings albeit preliminary may open up significant opportunities for novel applications in wound healing. 相似文献
707.
A histochemical analysis of mucous cells in the gills, buccal cavity and epidermis of the nine-spined stickleback, Pungitius pungitius L., using alcian blue and PAS, showed that most cells contained more than one type of glycoprotein. In all regions, the cell content of sialylated glycoproteins increased, and of sulphated glycoproteins decreased during adaptation to sea water. The histochemical properties of the cuticle-secreting cells in the epidermis were less easy to study, but it seems that their content of neutral glycoproteins increased and their content of acid glycoproteins decreased, during adaptation to sea water. Mucous cells were generally less common in seawater-adapted animals, though in the epidermis of fish kept in sea water for 21 days, there were as many as in the freshwater controls. Sulphated glycoproteins may be more effective than others in freshwater osmoregulation for they are highly charged and could attract cations strongly. They may also help to combat bacterial and fungal infections, and perhaps these are less likely when laboratory fish are transferred to sea water. 相似文献
708.
709.
Tejas M. Shah Jaina S. Patel Chandrakant D. Bhong Aakash Doiphode Uday D. Umrikar Shivnandan S. Parmar Dharamshibhai N. Rank Jitendra V. Solanki Chaitanya G. Joshi 《Animal genetics》2013,44(4):442-445
Evaluations of genetic diversity in domestic livestock populations are necessary to implement region‐specific conservation measures. We determined the genetic diversity and evolutionary relationships among eight geographically and phenotypically diverse cattle breeds indigenous to west‐central India by genotyping these animals for 22 microsatellite loci. A total of 326 alleles were detected, and the expected heterozygosity ranged from 0.614 (Kenkatha) to 0.701 (Dangi). The mean number of alleles among the cattle breeds ranged from 7.182 (Khillar) to 9.409 (Gaolao). There were abundant genetic variations displayed within breeds, and the genetic differentiation was also high between the Indian cattle breeds, which displayed 15.9% of the total genetic differentiation among the different breeds. The genetic differentiation (pairwise FST) among the eight Indian breeds varied from 0.0126 for the Kankrej–Malvi pair to 0.2667 for Khillar–Kenkatha pair. The phylogeny, principal components analysis, and structure analysis further supported close grouping of Kankrej, Malvi, Nimari and Gir; Gaolao and Kenkatha, whereas Dangi and Khillar remained at distance from other breeds. 相似文献
710.