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Physicochemical parameters of 31 fish pond water samples of Tripura were studied to ascertain the nutrient profile of acidic soil zone and the impact of water acidity towards aquaculture productivity. The pH was acidic (mean 6.63±0.44) with high Fe (mean1.04±0.40 mglˉ¹) and AI (mean 2.67±2.41 mglˉ¹) contents. These were mostly responsible for pond water acidity and poor productivity with low nitrogen, phosphate and total alkalinity. The study also showed strong negative relationship between water pH and redox potential (R²=0.5251). However, pH was positively significant with electrical conductivity. The roles of redox potential and electrical conductivity in water acidity were found highly important. Available calcium content was also found low (mean 2.91±2.96 mglˉ¹). Elevating level of pH of pond water could be the possible management practices in acidic water so that such unproductive water might be productive enough with higher phosphate and nitrogen levels for better biological production.

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Objective: To investigate the association of complement C4 null genes (C4QO, including C4AQO and C4BQO) and C2 gene with systemic lupus erythematosus (SLE) in southwest Han Chinese; 136 patients with SLE and 174 matched controls were genotyped. Methods: C4 null genes were determined by a polymerase chain reaction (PCR) procedure with sequence specific primers (PCR-SSP). The 2 bp insertion in exon 29, which was previously identified in non-Chinese populations and caused defective C4A genes, was directly typed by sequencing the whole exon 29 using exon specific primers. The exon 6 of complement C2 was also sequenced in both the patients and controls. Results: The frequency of homozygous C4AQO allele was 12.5% (17/136) in patients with SLE compared with 1.1% (2/174) in controls (p<0.001, odds ratio (OR)=12.286, 95% confidence interval (95% CI) 2.786 to 54.170). There was no significant difference for homozygous C4BQO allele between patients with SLE and controls (p=0.699). Patients with the C4AQO gene had an increased risk of acquiring renal disorder, serositis, and anti-dsDNA antibodies compared with those without C4AQO (for renal disorder, p=0.018, OR=8.951, 95% Cl 1.132 to 70.804; for serositis, p=0.011, OR 4.891, 95% CI 1.574 to 15.198; for anti-dsDNA, p=0.004, OR 7.630, 95%Cl 1.636 to 35.584). None of the patients or controls had the 2 bp insertion in exon 29 of the C4 gene. The type I C2 deficiency was not detected in the 3 10 samples. Conclusion: It is suggested that deficiency of C4A (not due to a 2 bp insertion in exon 29), but not C4B or C2, may be a risk factor for acquiring SLE in south west Han Chinese; this results in increased risk of renal disorder, serositis, and anti-dsDNA antibodies in patients with SLE. Racial differences seem to be relevant in susceptibility to SLE.

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通过对人免疫缺陷病毒复制过程的抑制作用研究,探索光动力疗法(PDT)在艾滋病防治中的潜在价值。使 用不同稀释浓度的光敏剂血卟啉单甲醚(HMME)和亚甲蓝(MB)分别与人免疫缺陷病毒HIV一1Ⅲs或宿主细胞 MT4,C8166或H9/HIV-IⅢB孵育2 h。以波长630 nm能量密度0.3 J/cm2的半导体激光进行照射。继续孵育若干 小时后,用噻唑蓝(MTT)比色法检测细胞存活率或合胞体计数,同时收集培养上清液用ELISA法检测HIV-I p24 抗原。结果表明,光动力疗法能显著抑制人免疫缺陷病毒诱导的细胞一细胞融合(HMME-PDT抑制率64.68%, MB-PDT抑制率61.56%)和病毒一细胞融合(HMME—PDT抑制率85%,Mt}PDT抑制率73.64%),并对游离病毒 有很强的杀伤作用,最高可达到100%。光动力疗法不能抑制慢性感染期和急性感染2 h后病毒的复制过程。可 见光动力疗法对游离病毒和病毒感染诱导的膜融合有显著抑制作用,有可能为艾滋病的防治提供一种新的方法。

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We exfoliate graphite in both aqueous and non-aqueous environments through mild sonication followed by centrifugation. The dispersions are enriched with monolayers. We mix them with polymers, followed by slow evaporation to produce optical quality composites. Nonlinear optical measurements show similar to 5% saturable absorption. The composites are then integrated into fiber laser cavities to generate 630 fs pulses at 1.56 mu m. This shows the viability of solution phase processing for graphene based photonic devices. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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In this research reared white western shrimp (Litopenaeus vannamei ,Boone, 1931) with five diet with five different protein level contain 20%, 25%, 30%, 35% and 40% and three salinity level contain 15-17 ppt, 27-30 ppt,and 40-45 ppt researched protein percent effect and water salinity on growth, survival, feed conversion ratio, hemolymph osmolatity, hemolymph protein and corpse protein contain. In this research was 15 sorrow with 3 repeat and used from 45 tanks with 300 liters capacity. Shrimps first weight average was about 2 grams and after 60 days culture cropped down results: Shrimps biomass growth in 15-17 ppt salinity was higher than anther salinities who had meaning different with growth in 40-45 ppt salinity ( p< 0.05). But hadn’t meaning different with growth 27-30 ppt salinity. survival rate in 15-17 ppt salinity was 97.03 who was lower than another salinities. survival percent in 24-30 ppt salinity and 40-45 ppt salinity was 99.33% Highest biomass growth in different diets was in diet number 5 with 40 percent protein that it had meaning different with another diets (p<0.05) . although with informed to product expense in different diets. One kilogram shrimp product expense in different diets hadn’t meaning different (P<0.05) Survival rate in different diets hadn’t meaning different lowest feed conversion ratio was 1.67 in 15-14 salinity that hadn’t meaning different with another salinities also corpse protein quantity in different salinities and different diets hadn’t meaning different. Hemolymph Osmolality in 15-17 ppt salinity was 573.88 mOsm/kg had meaning different with hemolymph osmolality in 27-30 ppt salinity that was 650. 380 mOsm/kg and in 40-45 ppt salinity was 630.38 mOsm/kg. Hemolymph protein in 15-17 ppt salinity was 124.72 mg/ml had meaning different with hemlymph protein in 27-30 ppt salinity that was 136.52 mg/ml but hadn’t meaning different with hemolymph protein in 40-45 ppt salinity that was 128.84 mg/ml. Hemolymph protein in different diets hadn’t meaning different (p<0.05). Keywords: shrimp, Litopenaeus vannamei, protein , salinity, growth, survival rate, FCR, hemolymph osmolality, hemolymph protein.

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本实验采用EP管反复冻融和研磨的破壁方式,利用溶菌酶法、CTAB法、改良CTAB法、尿素法、十二烷基硫酸钠(SDS)法等5种方法,分别对5种鱼类致病性水霉菌(寄生水霉、多子水霉、异株水霉及两未定种)的基因组DNA进行提取,并采用紫外分光光度计和ITS区基因(包括5.8SrDNA)PCR扩增对DNA进行了评价。紫外分光光度计检测结果表明,5种方法均可提取到水霉菌DNA,其中改良CTAB法提取的5种水霉菌的DNA产量和质量最高,A260/A280在1.79—1.82之间,浓度为45μg/mL;PCR检测结果表

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中国科学院留学回国人员择优基金; 中国科学院“百人计划”项目

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根据地史和东亚地区鱼类区系演化史 ,推测了金线属鱼类的起源时代及其与当时古地质和古气候事件的关系 ,认为该类群的原始祖先可能在第三纪晚期已经存在于云贵高原一带 ;较系统地研究了金线属鱼类的洞穴适应演化趋势 ,表明该类群在穴居适应过程中既表现出穴居鱼类的共同演化趋势 ,也表现出其独特的穴居适应方式。

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In order to guarantee a sustainable supply of future energy demand without compromising the environment, some actions for a substantial reduction of CO 2 emissions are nowadays deeply analysed. One of them is the improvement of the nuclear energy use. In this framework, innovative gas-cooled reactors (both thermal and fast) seem to be very attractive from the electricity production point of view and for the potential industrial use along the high temperature processes (e.g., H 2 production by steam reforming or I-S process). This work focuses on a preliminary (and conservative) evaluation of possible advantages that a symbiotic cycle (EPR-PBMR-GCFR) could entail, with special regard to the reduction of the HLW inventory and the optimization of the exploitation of the fuel resources. The comparison between the symbiotic cycle chosen and the reference one (once-through scenario, i.e., EPR-SNF directly disposed) shows a reduction of the time needed to reach a fixed reference level from ∼170000 years to ∼1550 years (comparable with typical human times and for this reason more acceptable by the public opinion). In addition, this cycle enables to have a more efficient use of resources involved: the total electric energy produced becomes equal to ∼630 TWh/year (instead of only ∼530 TWh/year using only EPR) without consuming additional raw materials. © 2009 Barbara Vezzoni et al.

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This experiment was designed to investigate the effect of dietary supplemental ascorbic acid (AA) on the feed intake, growth, serum lysozyme, hepatic superoxide dismutase (SOD) and handling stress response in Chinese longsnout catfish (Leiocassis longirostris Gunther) exposed to three levels of unionized ammonia nitrogen (UIA-N). Juvenile Chinese longsnout catfish were reared in 54 fibreglass tanks with a 3 x 3 factorial design treatment consisting of three supplemental AA levels in ascorbyl 2-monophosphate (38, 364 and 630 mg AA equivalent kg(-1) diet) and three UIA-N concentrations [0.004 (the control), 0.037 and 0.292 mg L-1]. The fish were sampled on the 11th, 32nd and 60th day. On the 62nd day, the remaining fish were subjected to an acute stress by being held in a dipnet out of water for 60 s, and sampled at 30 min post handling. The results showed that the specific growth rate (SGR) in 32 days significantly decreased with increased water UIA-N (P=0.0476) but was not affected by dietary supplemental AA (P > 0.05). After 60 days, SGR, feeding rate (FR) and feed conversion efficiency (FCE) significantly increased with increased dietary supplemental AA (P < 0.001) while remaining unaffected by water UIA-N (P > 0.05). There was no significant interaction between dietary AA and UIA-N for growth responses (P > 0.05). The serum lysozyme activity on the 11th day and the hepatic SOD activity on the 32nd day were significantly affected at high (0.292 mg L-1) water UIA-N. On the 62nd day, the increase in cortisol resulting from acute stress significantly decreased by higher UIA-N (P=0.038). It is suggested that Chinese longsnout catfish displayed an adaptive response after long-term UIA-N exposure, and AA had beneficial effects on the growth and feed intake of catfish and alleviated the negative effects of chronic ammonia stress. A chronically higher ammonia level shows a tendency to inhibit the cortisol response to another acute stressor.

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We report the growth of well-ordered InAs QD chains by molecular beam epitaxy system. In order to analyze and extend the results of our experiment, a detailed kinetic Monte Carlo simulation is developed to investigate the effects of different growth conditions to the selective growth of InAs quantum dots (QDs). We find that growth temperature plays a more important role than growth rate in the spatial ordering of the QDs. We also investigate the effect of periodic stress on the shape of QDs in simulation. The simulation results are in good qualitative agreement with our experiment. (c) 2006 Elsevier Ltd. All rights reserved.

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In this work we report the optical and microscopic properties of self-organized InAs/GaAs quantum dots grown by molecular beam epitaxy on (1 0 0) oriented GaAs substrates. A distinctive double-peak feature of the PL spectra from quantum dots has been observed, and a bimodal distribution of dot sizes has also been confirmed by scanning tunneling microscopy (STM) image for uncapped sample. The power-dependent photoluminescence (PL) study demonstrates that the distinctive PL emission peaks are associated with the ground-state emission of islands in different size branches. The temperature-dependent PL study shows that the PL quenching temperature for different dot families is different. It is shown that the coupling between quantum dots plays a key role in unusual temperature dependence of QD photoluminescence. In addition, we have tuned the emission wavelength of InAs QDs to 1.3 mu m at room temperature. (C) 2000 Elsevier Science B.V. All rights reserved.