光系统Ⅱ的非均匀性

以去垢剂Triton X—100 增溶莴苣、大豆和菠莱叶绿体，得到具有较高放氧活性的光系统Ⅱ（PSⅡ）颗粒。放氧活性在200~250u mol 02 ∕mgchl∙ hr,而光系统I活性很低。 对此颗粒进行了光诱导荧光动力学分析，表明在这三种植物的PSⅡ颗粒中仍存在着两个动力学相，即快速的、非指数型上升α相，和慢速的、指数型上升β相。并和其来源的叶绿体作了比较。 将ATP在光照和镁离子存在下与PSⅡ颗粒共同进行保温后，PSⅡ颗粒的荧光动力学参数发生了变化，α相含量降低，但去磷酸化可部分恢复。77K荧光发射光谱表明，保温后F685/F695比值降低了，去磷酸化也可部分恢复。 本文结合这些现象作了讨论。认为两类中心理论中关于α、β中心在膜上分区的假设是值得商榷的;动力学两相的存在无需以蛋白质分布横向非均匀性为前提条件，两类中心的模型在上述现象解释中不是令人满意的。

Towards a complete dense geometric and photometric reconstruction under varying pose and illumination

This paper proposes a novel framework to construct a geometric and photometric model of a viewed object that can be used for visualisation in arbitrary pose and illumination. The method is solely based on images and does not require any specialised equipment. We assume that the object has a piece-wise smooth surface and that its reflectance can be modelled using a parametric bidirectional reflectance distribution function. Without assuming any prior knowledge on the object, geometry and reflectance have to be estimated simultaneously and occlusion and shadows have to be treated consistently. We exploit the geometric and photometric consistency using the fact that surface orientation and reflectance are local invariants. In a first implementation, we demonstrate the method using a Lambertian object placed on a turn-table and illuminated by a number of unknown point light-sources. A discrete voxel model is initialised to the visual hull and voxels identified as inconsistent with the invariants are removed iteratively. The resulting model is used to render images in novel pose and illumination. © 2004 Elsevier B.V. All rights reserved.

超微量汞元素气相热色谱分离装置

本实用新型主要涉及超微量元素的分离装置，尤其涉及超微量汞元素气相热色谱分离装置。一种超微量元素气相热色谱分离装置，包括有外壳，真空泵，其主要特点是还包括有靶炉，其内设有放置铅靶片的石墨盒、测量热电偶；靶炉与长传输管相通，其上设有测量热电偶；长传输管上设有测量热电偶，其末端设有收集器及制冷装置。本实用新型对超微量汞元素（即被分离的元素原子数与可融化的金属块载体原子数的比在１∶１０↑［１６］至１∶１０↑［１２］之间）的高灵敏度、高效气相热色谱分离。特别适合于放射性汞的分离和收集，具有快速、高灵敏、高效的特点。

Seasonal fluctuation in primary production in relation to the physicochemical parameters of two weed-infested ponds of Kalyani, West Bengal

Kalyani lake (P sub(1)), a weed infested recreational water body and a weed chocked derelict water body (P sub(2)) in the heart of Kalyani city of West Bengal were studied for a period of one year for their primary productivity and other physicochemical parameters. Very low primary productivity (GPP=360-1237mg C m super(-2) d super(-1); NPP=157-787 mg C m super(-2) d super(-1)) was recorded in P sub(2) in spite of having a high concentration of nutrients (PO sub(4)–P=0.052-0.260mg l super(- 1); NO sub(3)-N=0.110-0.412mg l super(-1)). On the other hand, moderate primary productivity (GPP=1687-3195mg C m super(-2) d super(-1); NPP=900-2700mg C m super(-2) d super(-1)) was found in P sub(1) with comparatively low range of nutrients (P0 sub(4)-P =0.010-0.058mg l super(-1); NO sub(3)-N=0.032-0.118mg l super(-1)). After studying the other physicochemical parameters (temperature, transparency, dissolved oxygen, free carbon dioxide, pH, alkalinity and macrophytic biomass), it was found that the overall hydro-biological conditions of the weed-chocked derelict water body (P sub(2)) is not congenial for biological production as compared to Kalyani Lake (P sub(1)). Kalyani Lake may be used for fish culture with proper management practices.

FY is an RNA 3' end-processing factor that interacts with FCA to control the Arabidopsis floral transition

The nuclear RNA binding protein, FCA, promotes Arabidopsis reproductive development. FCA contains a WW protein interaction domain that is essential for FCA function. We have identified FY as a protein partner for this domain. FY belongs to a highly conserved group of eukaryotic proteins represented in Saccharomyces cerevisiae by the RNA 3' end-processing factor, Pfs2p. FY regulates RNA 3' end processing in Arabidopsis as evidenced through its role in FCA regulation. FCA expression is autoregulated through the use of different polyadenylation sites within the FCA pre-mRNA, and the FCA/FY interaction is required for efficient selection of the promoter-proximal polyadenylation site. The FCA/FY interaction is also required for the downregulation of the floral repressor FLC. We propose that FCA controls 3' end formation of specific transcripts and that in higher eukaryotes, proteins homologous to FY may have evolved as sites of association for regulators of RNA 3' end processing.

Fish farm technology. 1 - Brackishwater fish culture based on "aquafeed"

A method has been evolved to enhance the production of natural feed in brackish water fish farms by providing substrates for bio-growth ('aquafeed' production) which is a biomass complex consisting of sedentary and associated organisms of plant and animal species. The seasonal fluctuations of the aquafeed production over different substrates ranged as: 787-1830g/coconut leaf (6m²)/45 days, 16.0-072.9g/glass panel (2x10x10cm²)/30 days, 52-230g/nylon mat (2x25x25cm²)/30 days and 18.6-123.1g/wooden block (6x10x10cm²)/30 days. The average dry weight composition of the major components of aquafeed obtained in the present study was sand-silt-clay 40%, protein 22%, carbohydrate (water soluble) 1.8% and fat 3.35% (water content 85%). Mugil cephalus of 1.85 cm reared in a 0.01ha pond and fed on aquafeed attained a size of 23 cm length and 146.73g weight during one year. Survival rate was 54% at a density of 1000/ha. Salinity and temperature of the pond during the culture period ranged between 1.4 and 32.8‰ and 28.1 and 36.5°C respectively.

Neural representations of courtship song in the Drosophila brain.

Acoustic communication in drosophilid flies is based on the production and perception of courtship songs, which facilitate mating. Despite decades of research on courtship songs and behavior in Drosophila, central auditory responses have remained uncharacterized. In this study, we report on intracellular recordings from central neurons that innervate the Drosophila antennal mechanosensory and motor center (AMMC), the first relay for auditory information in the fly brain. These neurons produce graded-potential (nonspiking) responses to sound; we compare recordings from AMMC neurons to extracellular recordings of the receptor neuron population [Johnston's organ neurons (JONs)]. We discover that, while steady-state response profiles for tonal and broadband stimuli are significantly transformed between the JON population in the antenna and AMMC neurons in the brain, transient responses to pulses present in natural stimuli (courtship song) are not. For pulse stimuli in particular, AMMC neurons simply low-pass filter the receptor population response, thus preserving low-frequency temporal features (such as the spacing of song pulses) for analysis by postsynaptic neurons. We also compare responses in two closely related Drosophila species, Drosophila melanogaster and Drosophila simulans, and find that pulse song responses are largely similar, despite differences in the spectral content of their songs. Our recordings inform how downstream circuits may read out behaviorally relevant information from central neurons in the AMMC.

中国胭脂鱼线粒体控制区遗传多样性分析

利用PCR技术扩增了采自长江宜昌江段和清江的 8尾中国胭脂鱼线粒体DNA控制区全序列。研究发现该种具有脊椎动物线粒体控制区的一般结构 .在获得的 95 8bp的碱基序列中 ,共检测出 32个多态性核苷酸变异位点 ,多态位点比例为 0 .0 33。核苷酸的变异位点除一个为缺失外 ,其余全部为碱基转换 .变异位点主要集中在 5 5～36 5bp高变异区 ,而其他区域突变稀少。个体的变异在 0～ 1.36 %之间 ,表现出较大的个体多态性差异。中国胭脂鱼的线粒体控制区的变异远大于美国胭脂鱼 (Moxostoma

Endocrine disrupting effects on Chinese rare minnow (Gobiocypris rarus) fed with field collected Limnodrilus sp.

The potential endocrine disrupting effects and other toxicity effects on aquatic biota resulted from food uptake was simulated by feeding the laboratory cultured rare minnow(Gobiocypris rarus) with field collected Limnodrilus sp. The results indicated that the food chain processes affected significantly the growth, slightly reduced gonadosomatic indices, and elevated hepatosomatic indices. There was an obvious vitellogenin(VTG) induction, which generally only occurred in mature female, in the serum of juvenile rare minnow and mature male when fed with Limnodrilus sp. In addition, the rare minnow feeding on Limnodrilus sp. had significantly high renal indices, it meant obvious renal hyperplasia. The present work suggested that. Limnodrilus sp. from field water may contain toxic pollutants and could lead to endocrine disruption effects to the predators. It was concluded that endocrine disruptors may not only be assimilated through water, but also be bioconcentrated through food web. The results also suggested the importance of food selection in conducting the study of endocrine disruption effects using sensitive species.