放牧对典型草原土壤-植物系统中碳、氮、磷库特征的影响

放牧是内蒙古典型草原最主要的利用方式。放牧已对草原生态系统的结构和功能产生了巨大的影响。本论文研究了放牧对内蒙古典型草原土壤-植物系统中碳、氮、磷库特征的影响，结果表明： （1）草地开垦已使土壤C、N贮量显著损失。放牧已使羊草草原土壤C贮量表现出下降的趋势，大针茅草原没有表现出这种变化趋势。 （2）放牧尚没有使土壤全N发生显著变化，但土壤N素一些组分的比例发生了变化。放牧后，土壤NH_3-N下降，酸不溶态N比例有所提高;放牧使Fe-P比例显著降低。 （3）蒙古草原土壤微生物量C、N与土壤有机C、全N、降雨量、温度均表现出了很好的相关性。放牧对微生物量的影响与不同草原类型和放牧率有关。 （4）放牧使土壤养分元素的空间异质性加大。退化草地恢复过程中小叶锦鸡儿灌丛诱导了植物组成、生物量和土壤化学元素含量在空间上的分异，这种生态效应有利于退化草地的恢复。 （5）不同放牧强度对土壤C、N、P库和植物系统中C、N、P含量的影响不同。放牧使植物系统地上部C含量下降，N、P含量提高。高强度的放牧使土壤N、根系中的N素向表层相对聚集，表现出明显的表聚化现象。植物C/N、C/P比在中、重度放牧强度下最低，此时植物残体分解速率最高，极度放牧最终C、N循环速率减小。不考虑放牧率，研究放牧对土壤C、N、P含量的影响可能会得出矛盾的结论。 （6）放牧草地中低等植物地衣、蓝细菌在元素化学循环中的作用提高。地衣Xanthoparmelia camtschadalis （Ach.）的生物量在经度放牧草地中最高，其体内C、N含量与放牧率的关系与维管植物相似。退化草地中蓝细菌可能是最重要的N素来源。

Variability in a radiolarian time series and its relationship to climate

EXTRACT (SEE PDF FOR FULL ABSTRACT): Recently, paleoceanographers have been challenged to produce reliable proxies of climate variables that can be incorporated into climate models. In developing proxies using time series of annual radiolarian species fluxes from Santa Barbara Basin, we identify groups of species associated with years of extreme sea surface temperatures and sea level heights.

重金属离子镉对高等植物叶绿体光系统Ⅱ的影响的研究

本文研究了重金属离子Cd++、Pb++、Cu++、Zn++对高等植物（菠菜）离体叶绿体两个光系统光合电子传递功能的影响，以Cd++为代表重点研究了它对光系统II（PSII）的影响，首重讨论了Cd++在PSII的作用部位及作用方式。 Cd++、Pb++、Cu++、Zn++对高等植物叶绿体光合电子传递具有抑制作用，其中对PSII电子传递的抑制作用更为显著。PSII制剂的放氧活性比叶绿体的放氧活性对Cd++的毒害作用更加敏感。不同浓度的Cd++处理后，叶绿体全电子链的电子传递活性比放氧活性的降低速率快。这暗示着PSII氧化侧不是Cd++唯一的作用部位，在PSII电子传递链上还存在一个对Cd~(++)敏感的部位。 Cd++使叶绿体和PSII制剂的DCIP光还原活性降低;可变光受到抑制。加入PSII人工电子供体DPC仅使被抑制的DCIP光还原活性稍有恢复;而加入NH2OH对被抑制的可变荧光无影响。因此我们认为Ca++除了作用于PSII氧化侧外，还直接作用于PSII反应中心。这与Bazzaz和Govindje等提出的Cd++仅作用于PSII氧化侧的观点不同。我们认为可能是Cd++改变了叶绿体或PSII制剂类囊体膜的构型或内环境，使较多的PSII反应中心不易被光活化或使其钝化的缘故。 低温（-196℃）荧光发射光谱表明，Cd++使叶绿体的F686/F736及 F696/F736比值降低。另外，Cd++还可使叶绿体和PSII制剂的低温（-196℃）荧光激发光谱的F480/F436比值下降，使叶绿体表观吸收光谱变平。 温和的SDS-PAGE分析表明，Cd++处理后，叶绿体类囊体膜与PSII制剂类囊体膜中色素蛋白复合物LHC-II的部分寡聚体解聚成单聚体，叶绿体中LHC-II总量减少。进一步用梯度胶分析叶绿体类囊体膜的多肽组成。发现Cd++使属于LHC-II的多肽减少。表明Cd++引起了LHC-II的重新分配或它本身的解离。通过比较Cd++与Mg++对PSII活性的不同影响，我们认为Cd++使激发能不利于向PSII分配，从而破坏了两个光系统的协调合作。这或许是导致PSII电子传递活性显著降低的因素之一。

Three-dimensional interactions in the rotor of an axial turbine

This article presents a study of the development of the three-dimensional flowfield within the rotor blades of a low-speed, large-scale axial flow turbine. Measurements have been performed in the rotating and stationary frames of reference. Time-mean data have been obtained using miniature five-hole pneumatic probes, whereas the unsteady development of the flow has been determined using three-axis subminiature hot-wire anemometers. Additional information is provided by the results of blade-surface flow-visualization experiments and surface-mounted hot-film anemometers. The development of the stator exit flow, as it passes through the rotor blades, is described. Unsteady data suggest that the presence of the rotor secondary and tip leakage flows restricts the region of unsteady interaction to near midspan when the stator wakes and secondary flows are adjacent to the suction surface. Surface-mounted hot-film data show that this affects the suction-side laminar-turbulent transition process.

A closely integrated digital image capture device for embedded applications

A modular image capture system with close integration to CCD cameras has been developed. The aim is to produce a system capable of integrating CCD sensor, image capture and image processing into a single compact unit. This close integration provides a direct mapping between CCD pixels and digital image pixels. The system has been interfaced to a digital signal processor board for the development and control of image processing tasks. These have included characterization and enhancement of noisy images from an intensified camera and measurement to subpixel resolutions. A highly compact form of the image capture system is in an advanced stage of development. This consists of a single FPGA device and a single VRAM providing a two chip image capturing system capable of being integrated into a CCD camera. A miniature compact PC has been developed using a novel modular interconnection technique, providing a processing unit in a three dimensional format highly suited to integration into a CCD camera unit. Work is under way to interface the compact capture system to the PC using this interconnection technique, combining CCD sensor, image capture and image processing into a single compact unit. ©2005 Copyright SPIE - The International Society for Optical Engineering.

Economics of pond fish culture under BRAC supervision in Mymensingh, Bangladesh

This study examines the relative profitability of pond aquaculture (polyculture and monoculture of silver barb) under BRAC supervision in Trishal Upazila, Mymensingh district in Bangladesh. The results of the study showed that polyculture was economically more rewarding than monoculture, though both the farming activities were profitable. Production function analysis proved that inputs such as fingerlings, fertilizer, feed and manure had positive impact on output. Human labor and insecticides were over used. The coefficients had expected signs and were found to be very significant.

大蹼铃蟾缓激肽及其制备方法和其基因

本发明涉及大蹼铃蟾缓激肽及其制备方法和其基因，属于生物医学领域。其缓激肽为从中国两栖类动物大蹼铃蟾(Bombina maxima)皮肤分泌物中分离得到的由19个氨基酸组成的一种单链多肽，分子量2180，等电点11.7，多肽氨基酸全序列一级结构为：DLPKINRKGPRPPGFSPFR。制备方法是收集大蹼铃蟾皮肤分泌物，离心去除沉淀、冷冻干燥后，经凝胶过滤、高压液相反相柱层析分离纯化后即得到。编码大蹼铃蟾缓激肽基因核苷酸序列由cDNA由829个核苷酸组成，编码成熟大蹼铃蟾缓激肽为第140-196，224-280，308-364，392-448，476-532，560-616位6个核苷酸重复单元片断，从两栖类动物皮肤中得到的缓激肽基因作为基因工程制备缓激肽的应用。

Frog skins keep redox homeostasis by antioxidant peptides with rapid radical scavenging ability

The question of how amphibians can protect themselves from reactive oxygen species when exposed to the sun in an oxygen-rich atmosphere is important and interesting, not only from an evolutionary viewpoint, but also as a primer for researchers interested in mammalian skin biology, in which such peptide systems for antioxidant defense are not well studied. The identification of an antioxidant peptide named antioxidin-RL from frog (Odorrana livida) skin in this report supports the idea that a peptide antioxidant system may be a widespread antioxidant strategy among amphibian skins. Its ability to eliminate most of the 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical tested within 2 s, which is much faster than the commercial antioxidant factor butylated hydroxytoluene, suggests that it has a potentially large impact on redox homeostasis in amphibian skins. Cys10 is proven to be responsible for its rapid radical scavenging function and tyrosines take part in the binding of antioxidin-RL to radicals according to our nuclear magnetic resonance assay. (C) 2010 Elsevier Inc. All rights reserved.

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.

Feasibility of bi-culture of mud crab (Scylla serrata) and shrimp (Penaeus monodon)

A study on the feasibility of bi-culture of mud crab (Scylla serrata) and shrimp (Penaeus monodon) in brackishwater earthen ponds (0.1 ha each) was carried out for a period of five months (March-August). Nursed shrimp juvenile (ABL:· 3.36±0.23 em and ABW: 0.26±0.04 g) and crab juvenile (ACL: 2.61±0.22 cm, ACW: 4.63±0.11 cm and ABW: 43±2.64 g) were stocked following the experimental design of shrimp 2/m2 (Treatment-1), shrimp 2/m2 and mud crab l/m2 (Treatment-2) and shrimp 2/m2 and mud crab 0.5/m2 (Treatment-3). Crabs were fed with chopped trash tilapia @ 10~5%, while shrimp were fed with Saudi-Bangla shrimp feed @ 3~5% of biomass twice daily. Significantly (p<0.05) higher specific growth rate (SGR) of shrimp and mud crab was 1.86% (g/day) in T2 and 0.83% (g/day) in T3, respectively. The survival of shrimp and mud crab also varied significantly (p<0.05) with a higher mean value of74.63% in Tl and 51.04% in T3, respectively. The production of shrimp (424.09 kg/ha) was significantly (p<0.05) higher in Tl and that of mud crab (568.80 kg/ha) in T2. Significantly (p<0.05) highest total production of 871.29 kg!ha was in T2 followed by 708.52 kg/ha in T3 and 424.09 kg/ha in Tl. The results indicate that mud crab can be cultured at a stocking rate of 1/m2 together with shrimp at 2/m2 •

Extraction, PCR amplification, and sequencing of mitochondrial DNA from scent mark and feces in the giant panda

To expand the feasibility of applying simple, efficient, non-invasive DNA preparation methods using samples that can be obtained from giant pandas living in the wild, we investigated the use of scent markings and fecal samples. Giant panda-specific oligonucleotide primers were used to amplify a portion of the mitochondrial DNA control region as well as a portion of the mitochondrial DNA cytochrome b gene and tRNA(Thr) gene region. A 196 base pair (bp) fragment in the control region and a 449 bp fragment in the cytochrome b gene and tRNA(Thr) gene were successfully amplified. Sequencing of polymerase chain reaction (PCR) products demonstrated that the two fragments are giant panda sequences. Furthermore, under simulated field conditions we found that DNA can be extracted from fecal samples aged as long as 3 months. Our results suggest that the scent mark and fecal samples are simple, efficient, and easily prepared DNA sources. (C) 1998 Wiley-Liss, Inc.

Morphometric measurements as an index for estimating yield of meat of shell fishes, 1. Crab (Scylla serrata) Forskal

Sixty one observations on length-breadth and whole weight-meat weight relations of India crab (Scylla serrata) were made. From the length of crab (cm) the whole weight (gm) can be computed by the equation: log W=-0.1708+2.3341 log L. Similarly for any given length (cm) the meat weight (gm) can be found by the relation, log w=-1.5745+3.0148 log L.