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排序方式: 共有94条查询结果,搜索用时 15 毫秒
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Four male buffaloes of 3 to years were subjected to heavy loads during hot dry conditions for 3 h continuously. Rectal temperature, respiration rate and heart rate increased significantly. The blood pH, PO2, increased significantly and PCO2 declined. During work, buffaloes were not able to eliminate heat produced and exhibited such distress symptoms as profuse salivation, frothing, lack of leg co-ordination, excitement and tongue protrusion. The muzzle secretion of buffaloes increased greatly. Even 3 h after discontinuation of work, the physiological reactions had not fully disappeared. 相似文献
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Economics,adoption determinants,and impacts of micro-irrigation technologies: empirical results from India 总被引:1,自引:1,他引:0
Micro-irrigation technologies are promoted for various reasons in India. Despite the reported significant economic advantages,
and the concerted support of the government and NGOs, the current micro-irrigation area in India remains an insignificant
proportion of its potential. This paper analyzes: (1) the economics of alternative micro-irrigation technologies, (2) the
determinants of adoption, (3) the poverty outreach of the different micro-irrigation systems, and (4) the sustainability implications
of micro-irrigation adoption. In line with the findings of other studies, this study indicates that micro-irrigation technologies
result in a significant productivity and economic gains. The most important determinants of micro-irrigation adoption include
access to groundwater, cropping pattern, availability of cash, and level of education, the social status and poverty status
of the farmer. Contrary to the expectations, the majority of the current adopters of low-cost micro-irrigation systems are
the better-off farmers. The study indicates that the impact of micro-irrigation systems on the sustainability of groundwater
resources depends upon the magnitude of the overall productivity gain following the shift from traditional irrigation method
to micro-irrigation system, the pattern of use of the saved water, and the type and potential number of adopters.
This study was supported by the Comprehensive Assessment of Water Management in Agriculture (CA) and IWMI-TATA Water Policy
Program.
相似文献
R. E. NamaraEmail: |
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D Priya NL Selokar AK Raja M Saini AA Sahare N Nala P Palta MS Chauhan RS Manik SK Singla 《Reproduction in domestic animals》2014,49(2):343-351
The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT. 相似文献
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Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states. 相似文献
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Conversion of methane to higher hydrocarbons by its low-temperature activation without forming undesirable carbon oxides is of great scientific and practical importance. Methane can be highly activated, yielding high rates of conversion to higher hydrocarbons and aromatics (10 to 45 percent) at low temperatures (400° to 600°C), by its reaction over H-galloaluminosilicate ZSM-5 type (MFI) zeolite in the presence of alkenes or higher alkanes. The methane activation results from its hydrogen-transfer reaction with alkenes. 相似文献
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Upadhyay A Chompoo J Kishimoto W Makise T Tawata S 《Journal of agricultural and food chemistry》2011,59(7):2857-2862
AIDS and influenza are viral pandemics and remain one of the leading causes of human deaths worldwide. The increasing resistance of these diseases to synthetic drugs demands the search for novel compounds from plant-based sources. In this regard, the leaves and rhizomes of Alpinia zerumbet, a traditionally important economic plant in Okinawa, were investigated for activity against HIV-1 integrase (IN) and neuraminidase (NA). The aqueous extracts of leaves and rhizomes had IN inhibitory activity with IC(50) values of 30 and 188 μg/mL, whereas against NA they showed 50% inhibition at concentrations of 43 and 57 μg/mL, respectively. 5,6-Dehydrokawain (DK), dihydro-5,6-dehydrokawain (DDK), and 8(17),12-labdadiene-15,16-dial (labdadiene) were isolated from the rhizomes and were tested for enzyme inhibitions. DK and DDK strongly inhibited IN with IC(50) of 4.4 and 3.6 μg/mL, respectively. Against NA, DK, DDK, and labdadiene exhibited mixed type of inhibition with respective IC(50) values of 25.5, 24.6, and 36.6 μM and K(i) values ranging from 0.3 to 2.8 μM. It was found that DDK is a slow and time-dependent reversible inhibitor of NA, probably with a methoxy group as its functionally active site. These results suggest that alpinia could be used as a source of bioactive compounds against IN and NA and that DK and DDK may have possibilities in the design of drugs against these viral diseases. 相似文献