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121.
S. Mahapatra Sk. Kabita D. Bhattacharya S. Sarkar S. K. Juin S. Maitra P. Nath 《Fish physiology and biochemistry》2017,43(2):477-491
Two forms of vitellogenin (Vg: Vg1 and Vg2) were purified from the plasma of estradiol-17β (E2)-treated Indian walking catfish, Clarias batrachus, by gel filtration and adsorption chromatography. Native Vg1 and Vg2 had apparent molecular masses of 375 and 450 kDa, respectively, and both Vgs resolved into two similar major bands (95 and 67 kDa) in SDS-PAGE under reducing condition. Polyclonal antisera raised against each form of Vg were absorbed with a combination of hypophysectomized male catfish serum proteins and alternate Vg to ensure specificity. Immunological analyses verified the presence of Vg1 and Vg2 in the plasma of female catfish. Homologous ELISAs were developed for Vg1 and Vg2 using their respective harvested antisera, which exhibited the detection limit of 100 ng ml?1 for Vg1 and 40 ng ml?1 for Vg2, and low level of cross-reactivity (not parallel to the standard) was found with alternate Vg in each assay. Treatment of male catfish with E2 induced both Vgs showing a proportionate ratio of Vg1 to Vg2 at 5.6:1. Plasma concentrations of both Vgs measured by ELISAs at different reproductive phases of field collected female catfish increased in accordance with the ovarian development, keeping the proportionate ratio of Vg1 to Vg2 at about 2:1 in fish undergoing vitellogenesis during prespawning period and 1:20 during spawning period, suggesting that Vg1 may be the major Vg to contribute in yolk formation, whereas Vg2, besides its role in yolk formation, may facilitate other physiological functions. The present study, thus, demonstrates the occurrence of two unequally synthesized Vgs in the catfish. 相似文献
122.
Lei Wang Binoy Sarkar Christian Sonne Yong Sik Ok Daniel C. W. Tsang 《Soil Use and Management》2020,36(3):355-357
Rapid and far-reaching transitions are required to combat climate change and its impacts. Carbon capture and storage within mineral deposits is a promising solution to remove CO2 from the atmosphere. In-situ geological storage and ex-situ mineral sequestration are practically sufficient for sequestering all the anthropogenic CO2. Recent research reports that more than 95% of injected CO2 was mineralized into carbonates in two years by using in-situ geological approach, and mining wastes and secondary minerals were recycled as resources for ex-situ CO2 sequestration. However, geological activity is the major risk of in-situ storage, while high energy consumption and associated cost may limit the application of ex-situ carbonation. Significant technical breakthroughs of mineral and geological CO2 sequestration are therefore of vital importance to realize a “net-zero CO2 emissions” and even “carbon-negative” society. 相似文献
123.
Arsenic pollution in ground water in India and Bangladesh is considered to be the largest contamination problem in the world. About 15?–?18% of the area of West Bengal, India comes under the threat of arsenic (As) contamination and around 5.36 million people are exposed to this hazard. A detailed isoline map corresponding to variations in arsenic concentration and their spatial distribution was prepared for the study area, which comprised two villages Ghentugachi and Gotera in Nadia district, West Bengal and the total area covered was 808 hectares. The pattern of arsenic contamination was highly irregular and diverse. About 11.2% of the study area was affected most (?>?0.50?mg As l?1) with sample As values reaching 0.71 and 0.80?mg?l?1. About 22.5% of the area had As content between 0.20 and 0.50?mg?l?1 and 33.9% of study area had As content below the WHO guideline of 0.01?mg As/l. Thus the local population living around these areas is vulnerable and exposed to arsenic contamination. None of the water samples exceeded the allowable limit (1.0?mg As l?1) of As for water used in irrigation purposes. The spatial distribution map helped to determine zones with different As concentrations, making it possible to identify high-risk zones. 相似文献
124.
S. Sarkar S. K. Singh A. P. Singh S. R. Singh 《Archives of Agronomy and Soil Science》2013,59(6):417-428
A field trial was carried out during 1993–94 and 1994–95 winter seasons on Udic Ustochrept to evaluate the performance of dryland barley under varying profile moisture status and nitrogen levels. Three levels of initial moisture status of the root zone profile were: wet (100% field capacity), moderately wet (50% field capacity) and dry (rainfed) as the main treatment. The sub treatments were 0, 40, 60 and 80 kg N ha?1. During 15 to 60 days after sowing (DAS) availability of soil nitrogen and its uptake by the crop attained the highest values under wet regime. However, at 105 and 130 DAS dry moisture regime resulted in maximum values of both available soil nitrogen and plant nitrogen contents. In the same tune biomass production attained the higher values under wet regime as compared to the dry regime during 15 to 60 DAS and the trend was reverse at 105 DAS. Grain yield attained the highest value under dry regime followed by wet and moderately wet regimes. Irrespective of the profile moisture status both productivity and nitrogen use efficiency enhanced with the increase in nitrogen doses from 0 to 80 kg ha?1. Role of nitrogen was more pronounced under wet regime. 相似文献
125.
This study reports an experimental investigation on the effect of softeners, crosslinking conditions, and laundering on the comfort related and low stress mechanical properties of cotton fabrics with different weave constructions. Softeners with different chemical natures, in conjunction with the crosslinking agent and catalyst, were padded onto the cotton fabrics of three types of weave constructions, viz. plain, twill, and a newly developed plant-structured weave design. Two crosslinking conditions, namely dry and moist curing conditions, were compared. Scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectroscope were used to visualize and quantify the morphological and chemical changes on fabrics. The experimental results showed that the dry-crosslinking condition is preferable to achieve better comfort and easy-care properties, while moist-crosslinking condition is a better choice when strength-related properties are the main requirement. The study further showed that silicone elastomer softener can be applied to improve fabric strength whereas micro-emulsion of functional amino-polysiloxane plus emulsion containing polyalkylene is beneficial for comfort characteristic. The plant-structured cotton fabric finished in the dry-crosslinking condition with softener in nano-emulsion form can result in superb water absorption, excellent air permeability, good handle, acceptable strength, and improved easycare property. 相似文献
126.
Abhijit?MajumdarEmail author Bijan?Sarkar Prabal?Kumar?Majumdar 《Fibers and Polymers》2004,5(4):297-302
In many engineering applications, the final decision is based on the evaluation of a number of alternatives in terms of a
number of criteria. This problem may become very intricate when the selection criteria are expressed in terms of different
units or the pertinent data are difficult to be quantified. The Analytic Hierarchy Process (AHP) is an effective way in dealing
with such kind of complicated problems. Cotton fiber is selected or graded, in the spinning industries, based on several quality
criteria. However, the existing selection or grading method based on Fiber quality Index (FqI) is rather crude and ambiguous.
This paper presents a novel approach of cotton fiber selection using the AHP methodology of Multi Criteria Decision Making. 相似文献
127.
Sarkar M Schilffarth S Schams D Meyer H Berisha B 《Reproduction in domestic animals》2011,46(5):757-762
Thrombopoietin (TPO) is known to be involved in megakaryocytopoiesis, but its role in the control of ovarian function is unknown in cattle. The aims of this study were to demonstrate the expression of TPO and its receptor (c-MPL) in detail in bovine corpus luteum (CL) obtained from different stages of the oestrous cycle and during pregnancy--and to demonstrate that TPO/c-MPL system is expressed clearly in bovine follicles. Real-time RT-PCR (qPCR) and ELISA were applied to investigate mRNA expression of examined factors and TPO protein, respectively. In this investigation, increases in the concentrations of TPO protein and the mRNA expression of TPO and c-MPL were noticed during both early luteal stage and late luteal stage of the oestrous cycle. Furthermore, the expression of TPO/c-MPL system does not show any significant regulation in the CL throughout pregnancy. Highest co-expression of TPO/c-MPL system in both theca interna (TI) and granulosa cells (GC) in small follicles (<10 mm in diameter) was observed in this study that may suggest the possible role of TPO/c-MPL system in proliferation of TI and GC cells. To conclude, the results demonstrate the possible involvement of locally produced TPO/c-MPL system as a 'physiological filter' in bovine ovary where they may promote cell selection by inducing proliferation of viable cells and scavenging non-viable cells and thereby may play an important role in modulation of ovarian function. 相似文献
128.
Bhakat M Mohanty TK Raina VS Gupta AK Khan HM Mahapatra RK Sarkar M 《Tropical animal health and production》2011,43(6):1161-1168
The objective of the study was to determine the effect of season, period, age, bull, and ejaculate on semen quality in Sahiwal
bulls. Semen production records from 1996 to 2006 of 5,483 ejaculates from 46 Sahiwal bulls maintained at Artificial Breeding
Complex, NDRI, Karnal, India were analyzed using least square analysis of variance by LSML software package. The overall least
squares means of ejaculate volume (VOL), total volume per day (VOLD), mass activity (MA), initial motility (IM), sperm concentration
per ml (SPC), and sperm concentration per ejaculate (SPCE) were 3.79 ± 0.02 ml, 5.81 ± 0.06 ml, 2.32 ± 0.01, 55.47 ± 0.001%,
766.69 ± 5.50 × 106/ml and 3023.25 ± 30.15 × 106, respectively. All semen traits (VOL, VOLD, MA, IM and SPCE) were significantly (P < 0.01) affected by age groups, season and period, whereas season had significant effect on VOL at 5% level. During hot-humid
season, highest value of VOL, VOLD, MA, IM, SPC, and SPCE were observed followed by summer and cold season. Highest value
of VOL, VOLD, IM, and SPCE were observed during period-3 (2004–2006), whereas highest value of MA and SPC were observed during
period-1 (1996–1999). However, lowest magnitude of MA, IM, SPC, and SPCE during period-2 (2000–2003) was observed. Ejaculate
characteristics like VOL, VOLD, and SPCE increased with the increasing age of bull up to 5 years and then decreased. Significant
(P < 0.01) bull to bull variation was found in VOL, VOLD, MA, IM, SPC, and SPCE traits. First ejaculate had significantly (P < 0.01) higher MA, IM, SPC, and SPCE. Hence, it could be concluded that during rainy season and period-1 and period-3 the
quality of semen is quantitatively and qualitatively good. Better quality semen was obtained up to 5 years of age in Sahiwal
bulls. 相似文献
129.
Genomic amplification with transcript sequencing 总被引:48,自引:0,他引:48
130.
Uttam Kumar Sarkar Prashant Kumar Deepak Raje Singh Negi T Ahmad Qureshi & Wazir Singh Lakra 《Aquaculture Research》2007,38(13):1404-1410
In the present study, the growth and survival of early life stages (ELS) of Chitala chitala were studied in nylon hapa for 28 days, followed by rearing in fibreglass reinforcement plastic (FRP) tanks for a period of 30 days. Ten‐day‐old ELS of C. chitala reared in hapa were fed with three different diets namely Indian Major Carp (IMC) spawn (<8 mm), live tubifex and fresh fish eggs. In the second phase, 28‐day‐old ELS were stocked in 200‐lit FRP tank and supplied four different live diets namely live tubifex worm, chironomous larvae, zooplanktons and mosquito larvae. Fish accepted all types of diets in the experimental rearing period in both the systems. The experiments conducted in hapa showed a higher specific growth rate (SGR), weight gain per cent and survival rate in larvae fed with live tubifex (SGR=1.76±0.02) than fish eggs (0.77±0.31) and IMC spawn (0.46±0.12). The study carried out in FRP tanks revealed that SGR was higher in ELS fed on chironomous larvae (4.44±0.61), followed by mosquito larvae (3.29±0.40) and live tubifex (3.28±0.36), whereas minimum SGR was recorded with zooplanktons (2.84±0.66). A significant difference (P<0.05) in SGR, final mean weight and weight gain (%) was also recorded. The highest mean survival rate (100%) of ELS in an FRP tank was observed in chironomous larvae and zooplanktons, whereas with live tubifex and mosquito larvae the same survival rate (80%) was recorded. The rate of survival of the ELS reared in hapa varied from 65% to 85%. The experiments showed that ELS of C. chitala could be reared successfully in hapas and fibreglass reinforcement tanks for attaining better survivability and growth. 相似文献