Acute toxicity of chlorpyrifos, cadusafos and diazinon to three Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala) fingerlings

Fingerlings of three Indian major carps, viz. Catla catla (Hamilton-Buchanon), Labeo rohita (Hamilton-Buchanon) and Cirrhinus mrigala (Hamilton-Buchanon), were exposed to different concentrations of chlorpyrifos (lorsban 10 G), cadusafos (rugby 10 G) and diazinon (basudin 10 G) for a period of 96h with a view to determine the median lethal concentrations (LC sub50) values for each of chemicals. Of the tested concentrations, chlorpyrifos at a dose of 6.65 ppm, cadusafos at 2.0 ppm and diazinon at a dose of 8.40 ppm or above induced 100% mortalities within 96h of exposure. The 96h LC sub50 values of chlorpyrefos, cadusafos and diazinon were 1.66, 0.72 and 2.10 ppm for C. catla, 2.35, 0.72 and 2.97 for L. rohita and 2.35, 0.72 and 2.10 ppm for C. mrigala, respectively. Pesticide induced behavioral abnormalities observed in the present study included erratic movements, rapid operculum activities, jumping of fish out of the test media, violent spasm and convulsion.

Seasonal variation in the distribution and availability of Carangids ("Paraw" and "Parati") in the Wadge Bank

The Wadge Bank has been exploited regularly by Ceylon based trawlers since 1955 (Sivalingam & Medcof 1957). The bank is about 4,000 sq. miles in extent (Malpas 1926) and is located south of Cape Comorin within the Continental Shelf of India (Fig. 1). Carangids are taken in large numbers during the months of the south west monsoon (Sivalingam 1966). The quantity, in which the Carangids are captured as shown by the fishing records, is large enough to influence the total catch from the bank during these months (Fig. 2). Carangids are held in high esteem as excellent quality food fishes and accordingly constitute a commercially important group. This paper records the results of a detailed examination of the past fishing records in respect of this group, based on the analysis of the catch and fishing effort for the years 1957 to 1962. The distribution pattern of this group of fish in the Wadge Bank is discussed.

Theoretical and numerical investigation of SiC JFET and MOSFET at 6.5 kV

This paper presents a preliminary theoretical and numerical investigation of 4H-SiC JFET and MOSFET at 6.5 kV. To improve the on-state/breakdown performance of the JFET, buried layers in conjunction with a highly doped buffer layer have been used. Trench technology has been employed for the MOSFET. The devices were simulated and optimized using MEDICI[I] simulator. From the comparison between the two devices, it turns out that the JFET offers a better on-state/breakdown trade-off, while the trench MOSFET has the advantage of MOS-control.

眼镜蛇科 cathelicidin 基因的分子克隆及活性研究

Cathelicidins 是天然免疫系统中的一种带正电的宿主防御肽段，它们广泛地 分布在哺乳类及其他一些物种如鱼类，鸟类中。它们均包含保守的前肽区和多变 的C-末端成熟抗菌肽区域，该抗菌肽区域无论是在种间还是种内都不保守。 我们首次分别从爬行纲眼镜蛇科的眼镜蛇，金环蛇，眼镜王蛇三种毒蛇的毒 腺cDNA 文库中克隆了3 个cathelicidin 编码序列。所克隆到的序列编码的开放 阅读框架均长576bp，编码191 个氨基酸残基组成的蛋白前体。从cDNA 开放阅 读框推导得到的毒蛇cathelicidin 都含有22 个氨基酸残基组成的信号肽， 135 个 氨基酸残基组成的cathelin 保守区域以及34 个氨基酸残基组成的成熟肽区域。 与哺乳类中的cathelicidin 基因的高度多样性不同，来源于3 种毒蛇的cathelicidin 基因在核酸和蛋白水平都比较保守。结构分析表明，以上3 种毒蛇的cathelicidin 成熟肽由第157 位的Val 被elastase 切割而产生。采用化学合成法合成推导得到 的眼镜王蛇的cathelicidin（OH-CATH）。在1% NaCl 的浓度下，该合成肽对测试 的多种细菌具有很强的抑菌活性，MIC 值为1-20 μg/ml。与此同时，即使当浓度 高达200 μg/ml 时，该合成的肽段对人的红细胞依然没有溶血活性。对脊椎动物 的cathelicidin 遗传进化树分析发现毒蛇类的cathelicidin 聚在一起。从进化上看， 蛇的cathelicidin 与来源于小鼠、大鼠、兔的中性粒细胞颗粒蛋白更接近。毒蛇 的cathelicidin 可能为新药开发提供了一个很好的模板。

Carbon nanotube based photocathodes for high frequency amplifiers

The combination of high frequency, high power, high efficiency capabilities is a feature of vacuum tube technology. For most of applications, large bandwidths are required, and therefore the modulation method should also allow large bandwidth operation. Optically modulated cold cathodes, avoiding the use of resonant cavities, should satisfy this requirement. This is the reason why we have developed carbon nanotube based photocathode.© 2009 IEEE.

Abundance, migration and management of Jatka (juvenile hilsa, Tenualosa ilisha) in the Gajner Beel, Pabna, Bangladesh

Studies on the abundance, migration and management of Jatka (juvenile hilsa, Tenualosa ilisha) were conducted in the Gajner Beel, located at the south-east corner of the Pabna Irrigation and Rural Development Project (PIRDP) in Sujanagar Upazila of Pabna district, Bangladesh. The main Jatka season was found to be extended from mid August to mid October. Veshal/Bandh/Khora Jal (lift net) and Ber Jal (beach seine net) were found as the major gears involved in Jatka fishing. The estimated total amount of Jatka caught from the Beel during the studied season was 46.2 t. The migratory route of Jatka is extended from the Padma and/or Jamuna rivers to the Badai river and then to the Beel through the sluice gate. The possibility of breeding of hilsa in the Beel was nullified. Finally, a community based management plan was suggested for implementation by the Gajner Beel management committee.

Mapping of the Indian fisheries growth rate and fish consumption through GIS

In the present study, Indian fisheries growth rate and fish consumption have been analyzed through GIS mapping. The analyses were based on the state-level fisheries data of India collected from the secondary sources. Accordingly, the paper contains one thematic map containing two layers. To achieve this, all the data have been brought into a tabular form through Microsoft Excel and then joined to Map Info Professional Version 8.0 GIS software with digitized map of India for further analysis to generate thematic maps. In this thematic map, the first Jayer represents the growth-rate of fish production for the period 1990-2004 and the second layer represents fish consumption for the year 2003. The thematic map represented in graphic form presents inland, marine and total growth rates, and also the rural and urban fish consumption at the state levels. This study will be useful to fish traders, planners, researchers and administrators in fisheries policy formulation for sustainable development.

Methylation and gene mutation in eukaryotic DNA

5-methylcytosine (m(5)C) as a rare base exists in eukaryotic genomes, which is a normal constitution in many eukaryotic DNA and the existence of m(5)C is a feature of eukaryotic DNA. Under regular physiological conditions, cytosine of eukaryotic DNA is usually methylated. Up to the present, many people consider that the m(5)C may be mutation hotspots by the deamination leading to gene mutation. Our study indicated that the spontaneous mutation caused by the transition of G.C --> A.T, in eukaryotic DNA, may result from the tautomer changing of base pairs and may also be cause by other factor actions, however it could not be caused by the deamination of m(5)C.

Pharmacokinetics of sifuvirtide, a novel anti-HIV-1 peptide, in monkeys and its inhibitory concentration in vitro

Aim: To study the pharmacokinetics of sifuvirtide, a novel anti-human immunodeficiency virus (HIV) peptide, in monkeys and to compare the inhibitory concentrations of sifuvirtide and enfuvirtide on HIV-1-infected-cell fusion. Methods: Monkeys received 1.2 mg/kg iv or sc of sifuvirtide. An on-line solid-phase extraction procedure combined with liquid chromatography tandem mass spectrometry (SPELC/MS/MS) was established and applied to determine the concentration of sifuvirtide in monkey plasma. A four-I-127 iodinated peptide was used as an internal standard. Fifty percent inhibitory concentration (IC50) of sifuvirtide on cell fusion was determined by co-cultivation assay. Results: The assay was validated with good precision and accuracy. The calibration curve for sifuvirtide in plasma was linear over a range of 4.88-5000 mu g/L, with correlation coefficients above 0.9923. After iv or sc administration, the observed peak concentrations of sifuvirtide were 10626 +/- 2886 mu g/L and 528 +/- 191 mu g/L, and the terminal elimination half-lives (T,12) were 6.3 +/- 0.9 h and 5.5 +/- 1.0 h, respectively. After sc, T-max was 0.25-2 h, and the absolute bioavailability was 49% +/- 13%. Sifuvirtide inhibited the syncytium formation between HIV-1 chronically infected cells and uninfected cells with an IC50 of 0.33 mu g/L. Conclusion: An on-line SPE-LC/MS/MS approach was established for peptide pharmacokinetic studies. Sifuvirtide was rapidly absorbed subcutaneously into the blood circulation. The T-1/2 of sifuvirtide was remarkably longer than that of its analog, enfuvirtide, reported in healthy monkeys and it conferred a long-term plasma concentration level which was higher than its IC50 in vitro.

懒猴能量需求的研究

三组成年懒猴(Nycticebus coucang bengalensis)日均摄入量能值分别为210.19kJ/kG, 177.222kJ/kG和161.608kJ/kG; 日均消化能分别为191.89kJ/kG, 155.131kJ/kG 和146.783kJ/kG。据统计学方差及t测验分析表明:I—Ⅱ组之间和I—Ⅲ之间的日 均摄食量能值及日均消化能均有显著性差异。实验结果表 明: I组所饲喂的配 合饲料的组成优于Ⅱ、Ⅲ组并可做为懒猴 的长期用配方。表4参8

黑长臂猿（Hy lobates concolor）对人类和非人类捕食者的回避行为

捕食和避免捕食在动物生存和进化过程中起着重要作用．本文报道了我们自１９９０年３月至．１９９２年元月观察黑长臂猿（Ｈｙｌｏｂａｔｅｓｃｏｎｃｏｌｏｒ）对人类和非人类捕食者的一系列反映．在遇到人类（观察者）后，据离观察者的远近和受惊程度不同，它们表现出５种回避方式．而在遇到非人类捕食者时，成年雌雄性一起将捕食者引开，以保护其后代个体免遭捕食．文中还对这些不同的行为方式进行了讨论．成年雄性是群体的主要保护者，成年雌性在群体保护中也起到重要的作用，不同个体的邀免捕食行为又有所不同，特别是幼体．