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The aim of the present study was to examine whether cumulus and fibroblast cell nuclear-transferred oocytes, which have high and low potential to develop into normal calves, respectively, are different in terms of in their patterns of timing of first cleavage and in their relationships between timing of first cleavage and in vitro developmental potential. The timing of first cleavage was similar in both types of nuclear-transferred and in vitro fertilized oocytes. More than 86% of the oocytes cleaved within 24 h after activation or in vitro fertilization; these oocytes contributed to more than 98% of the total number of blastocysts in all three groups. The potential of oocytes that cleaved at different intervals to develop into blastocysts differed among the groups. The developmental potential of the cumulus cell nuclear-transferred oocytes and in vitro fertilized oocytes decreased with the increase in time required for cleavage. Fibroblast cell nuclear-transferred oocytes that cleaved at 20 h, an intermediate cleaving time, had higher potential to develop into blastocysts. The results of the present study suggest that the type of donor nucleus used for nuclear transfer affects the timing of first cleavage. 相似文献
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Identification of genic SSRs in jute (Corchorus capsularis,Malvaceae) and development of markers for phenylpropanoid biosynthesis genes and regulatory genes 
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Kwasi Bannor Richard Amarnath Krishna Kumar Gupta Oppong-Kyeremeh Helena Abawiera Wongnaa Camillus 《水稻科学》2020,27(1):56-66
The factors affecting the adoption of modern varieties(MVs) of rice and impact on poverty in Odisha, India were discussed. A total of 363 households from Cuttack and Sambalpur districts of Odisha via multistage sampling technique participated in the survey. The Cragg's Double hurdle model was used to model the determinants of adoption and intensity of adoption of MVs of rice, and the propensity score matching was used to analyze the impact of adoption on poverty. The results showed that age, education, risk aversion, land size, yield, perception of MVs as high yielding, resistant to diseases and availability of MVs positively influenced the decision to adopt. However, variables such as household size, experience of a farmer, off-farm job participation, amount of credit received, cost of seeds, insecticides and fertilizers negatively influenced the adoption of MVs. Intensity of adoption of MVs was negatively influenced by experience of a farmer, cost of fertilizer and marketability of MVs, and positively affected by household size, risk aversion, land size, cost of insecticides, perception of MVs as high yielding and availability of MV seeds. Poverty incidence, gap and severity were high among non-adopters to adopters of MVs. After matching adopters and non-adopters of MV groups using four different algorithms of nearest neighbour matching, stratification matching, radius matching and kernel matching, the impact of MV adoption resulted in higher per capita monthly household expenditure by about US$ 52.82 to US$ 63.17. 相似文献
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Ether and methanol extracts of Ixora coccinea dry leaves were tested for their antimicrobial activity. Ether fraction was found to be more active than the methanol fraction. 相似文献
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Singha A Gibertini M Karmakar B Yuan S Polini M Vignale G Katsnelson MI Pinczuk A Pfeiffer LN West KW Pellegrini V 《Science (New York, N.Y.)》2011,332(6034):1176-1179
Artificial crystal lattices can be used to tune repulsive Coulomb interactions between electrons. We trapped electrons, confined as a two-dimensional gas in a gallium arsenide quantum well, in a nanofabricated lattice with honeycomb geometry. We probed the excitation spectrum in a magnetic field, identifying collective modes that emerged from the Coulomb interaction in the artificial lattice, as predicted by the Mott-Hubbard model. These observations allow us to determine the Hubbard gap and suggest the existence of a Coulomb-driven ground state. 相似文献
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We report the effects of shifting cultivation on water quality in 16 creeks investigated once in 2007 and twice in 2008 in 16 apparently similar small neighboring watersheds,each of 3 to 5 ha,at four locations around Barkal sub-district under Rangamati District of Chittagong Hill Tracts in Bangladesh.Concentrations of SO 4 2and K +,and pH in creek water were lower,and NO 3-N and Na + concentrations were higher in shifting-cultivation land compared to land with either plantation or natural forest or a combination of these cover types.Shifting cultivation effects on some water quality parameters were not significant due to change in land cover of the watershed between two sampling periods either through introduction of planted tree species or naturally regenerated vegetation.Conductivity and concentrations of HCO 3,PO 4 3,Ca 2+ and Mg 2+ in creek water showed no definite trend between shifting cultivation and the other land cover types.At one area near the Forest Range Office of Barkal,creek water pH was 5.8 under land cover with a combination of shifting cultivation and plantation.At this area Na + concentration in shifting-cultivation land ranged from 32.33 to 33.00 mg L-1 and in vegetated area from 25.00 to 30.50 mg L-1 in 2007.At another area,Chaliatali Chara,SO 4 2concentration in a shifting-cultivation watershed ranged from 4.46 to 10.51 mg L-1,lower than in a vegetated watershed that ranged from 11.69 to 19.98 mg L-1 in 2007.SO 4 2concentration in this shifting-cultivation area ranged from 1.28 to 1.37 mg L-1 and in the vegetated area from 1.37 to 3.50 mg L-1 in 2008. 相似文献
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Gograj Singh Jat Anilabh Das Munshi Tusar Kanti Behera Harshwardhan Choudhary Prasanta Dash Amarnath Ravindran 《The Journal of Horticultural Science and Biotechnology》2019,94(1):24-32
Gynoecious is an important economic trait of cucumber for determinant of earliness and yield, yet genetic mechanism is not well understood for this trait. The experiment was conducted using F2 mapping population by crossing of PPC-2, a gynoecious and parthenocarpic line with Pusa Uday (monoecious and non-parthenocarpic cultivar). Out of 179 SSR markers screened, 39 markers differentiated the gynoecious and monoecious parents. However, only 17 markers were segregating with F2 mapping population, those were used for genotyping and linkage map analysis and these markers were placed along with F locus on chromosome 6 covering a total distance of 100.4cM. The SSR markers, SSR13251 and UW020605 were found to be closely linked to gynoecious (F) locus at 1.0 and 4.5 cM, respectively. The segregation of F2 population of PPC-2 × Pusa Uday and GPC-1 × Punjab Naveen and test crosses for sex type herein suggested that single dominant gene controlled the gynoecious sex expression in cucumber particularly in gynoecious genotypes PPC-2 and GPC-1. Therefore, the monogenic dominant nature of gynoecious sex identified in the present experiment and SSR markers closely linked to the F locus will be useful in marker-assisted backcross breeding for transfering gynoecious trait into horticulturally desirable varieties. 相似文献