A new species of Allocreadium (Trematoda : Allocreadiidae) from freshwater fishes in the Danjiangkou Reservoir in China

A new species of Allocreadium, Allocreadium danjiangensis n. sp., is described from the intestine of several species of freshwater fish, including Abbottina rivularis (Basilewsky, 1855), Sarcocheilichthys nigripinnis nigripinns (Gunther, 1873), Gnathopogon argentatus (Sauvage et Dabry 1874), Opsariichthys uncirostris bidens (Gunther, 1873), and Erythroculter mongolicus mongolicus (Basilewsky, 1855) (Cyprinidae) from the Danjiangkou Reservoir in central China. The main morphological characters of the new species are as follows: vitelline follicles numerous, extending from the level of acetabulum to posterior extremity, distributed over both sides around the ceca; cirrus sac relatively large, developed, lying obliquely anterior to the acetabulum, extending from the level of the intestinal bifurcation to the central level of acetabulum, and overlapping left or right cecal; and ovary much smaller than testes, generally close to or even overlapping the anterior border of anterior testis. Observation by scanning electron microscopy shows only 2 kinds of tegumental formations, i.e., papillae and tubercles, instead of 3 types of tegumental formations, i.e., papillae, bosses, and minute sensor receptors observed on other species of the Allocreadiidae. The tegumental striations of the present species vary on the different parts of the body. In addition, a new structure, identified as the "groove" with a tonguelike tubercle, was observed on the inner wall of acetabulum.

Identification and characterization of a MBP isoform specific to hypothalamus in orange-spotted grouper (Epinephelus coioides)

Myelin basic protein (MBP), as a major component of the myelin sheath, has been revealed to play an important role informing and maintaining myelin structure in vertebrate nervous system. In teleost, hypothalamus is an instinctive brain center and plays significant roles in many physiological functions, such as energy metabolism, growth, reproduction, and stress response. In comparison with other MBP identified in vertebrates, a smallest MBP is cloned and identified from the orange-spotted grouper hypothalamic cDNA plasmid library in this study. RT-PCR analysis and Western blot detection indicate that the EcMBP is specific to hypothalamus, and expresses mainly in the tuberal hypothalamus in adult grouper. Immunofluorescence localization suggests that EcMBP should be expressed by oligodendrocytes, and the expressing cells should be concentrated in hypothalamus and the area surrounding hypothalamus, such as NPOpc, VC, DP, NLTm, and NDLI The studies on EcMBP expression pattern and developmental behaviour in the brains of grouper embryos and larvae reveal that the EcMBP-expressing cells are only limited in a defined set of cells on the border of hypothalamus, and suggest that the EcMBP-expressing cells might be a subpopulation of oliaodendrocyte progenitor cells. This study not only identifies a smallest MBP isoform specific to hypothalamus that can be used as a molecular marker of oligodendrocytes in fish, but also provides new insights for MBP evolution and cellular distribution. (C) 2007 Elsevier B.V.. All rights reserved.

Excision of Sleeping Beauty transposons: parameters and applications to gene therapy

A major problem in gene therapy is the determination of the rates at which gene transfer has occurred. Our work has focused on applications of the Sleeping Beauty (SB) transposon system as a non-viral vector for gene therapy. Excision of a transposon from a donor molecule and its integration into a cellular chromosome are catalyzed by SB transposase. In this study, we used a plasmid-based excision assay to study the excision step of transposition. We used the excision assay to evaluate the importance of various sequences that border the sites of excision inside and outside the transposon in order to determine the most active sequences for transposition from a donor plasmid. These findings together with our previous results in transposase binding to the terminal repeats suggest that the sequences in the transposon-junction of SB are involved in steps subsequent to DNA binding but before excision, and that they may have a role in transposase-transposon interaction. We found that SB transposons leave characteristically different footprints at excision sites in different cell types, suggesting that alternative repair machineries operate in concert with transposition. Most importantly, we found that the rates of excision correlate with the rates of transposition. We used this finding to assess transposition in livers of mice that were injected with the SB transposon and transposase. The excision assay appears to be a relatively quick and easy method to optimize protocols for delivery of genes in SB transposons to mammalian chromosomes in living animals. Copyright (C) 2004 John Wiley Sons, Ltd.

Proposal of an Ultracompact Triplexer Using Photonic Crystal Waveguide with an Air Holes Array

We propose an ultracompact triplexer based on a shift of the cutoff frequency of the fundamental mode in a planar photonic crystal waveguide (PCW) with a triangular lattice of air holes. The shift is realized by modifying the radii of the border holes adjacent to the PCW core. Some defect holes are introduced to control the beam propagation. The numerical results obtained by the finite-difference time-domain method show that the presented triplexer can separate three specific wavelengths, i.e. 1310, 1490 and 1550 nm with the extinction ratios higher than - 18 dB. The designed device with a size as compact as 12 mu m x 6.5 mu m is feasible for the practical application, and can be utilized in the system of fiber to the home.

Dose rate dependence of electrical characteristics of lead zirconate titanate capacitors

The influence of gamma-radiation dose rate on the electrical properties of lead zirconate titanate capacitors was investigated. More severe degradations in dielectric constant, coercive field, remanent polarization and capacitance-voltage (C-V) curves occurred with increasing radiation dose at lower dose rates. The electrical properties exhibited distinct radiation dose rate dependence and the worst-case degradation occurred at the lowest dose rate. The radiation-induced degradation of parameters such as the coercive field drift and distortion of the C-V curve can be recovered partly through post-irradiation annealing.

夏玉米低定额畦灌田间试验研究

为了合理利用水资源,探索实现低定额均匀灌溉的适宜方法和技术路线,设计作物高效用水的有限灌溉制度,在陕西省杨凌区中壤土玉米地开展了不同畦田规格和灌水定额对土壤水分及玉米产量影响的田间试验。结果表明:对于田面坡度一定的试验田块,入畦单宽流量在3～6lm/s范围内,畦田宽度在4m以内时,各处理小区的土壤平均含水量无显著性差异,但畦田内土壤水分分布却有不同差异,当畦宽2～3m,畦长50m时可达到较高灌水效率(Ea>80%)和灌水均匀度(DU>80%);玉米拔节-抽雄期的灌水定额处理对玉米的生长存在明显影响;不同灌水定额对作物产量、水分利用效率影响显著。

低定额畦灌技术参数研究

基于有限水资源的农田补充灌溉,以寻求不产生深层渗漏的节水型地面畦灌灌水定额为目标,在陕西省杨陵区中壤土玉米地,开展了畦田规格和灌水技术要素对灌水效率和灌水均匀度影响的田间试验。通过水流推进、消退过程、土壤水分变化的测定,利用地面灌溉水流运动曲线拟合对畦灌条件下的最佳灌水技术要素组合进行了分析。结果表明:畦田规格和灌水技术要素对灌水效率和灌水均匀度具有明显影响,对于试验田块,田面坡度为1.5‰时,入畦单宽流量控制在3～6L/(m.s)范围内,畦宽2～3m,畦长50m左右,可达到较高灌水效率(Ea>80%)和灌水均匀度(DU>80%),并能将灌水定额控制在设计范围之内,实现畦田的小定额灌溉。

计算流体力学教程

本书属于“中科院研究生院教材”系列。本书主要介绍计算流体力学中的有限差分算法和有限体积算法及它们的应用。全书共分上、下两篇：上篇共有8章，主要介绍差分算法理论基础；下篇共有6章，主要介绍差分算法应用研究和网格生成技术。为便于读者学习和应用，配书光盘包含配合各种算法的若干算例和用Fortran77和C语言编写的计算程序。本书强调基础、突出应用、关注最新进展。通过学习本书，读者能对计算流体力学有一个系统和深入的理解，并掌握扎实的理论基础和具备较强的解决实际问题的能力。 本书可作为力学、机械、航空航天、热能等专业及相关专业的研究生教学用书，以及高年级的本科生学习计算流体力学的教材，也可作为从事数值模拟的科研人员和工程技术人员的参考书。

可压缩湍流直接数值模拟

本书是以作者及其研究小组多年来的研究工作为基础撰写的，主要是可压缩湍流的直接数值模拟。全书共分两部分。第一部分为数值模拟方法：针对可压缩湍流的多尺度非定常非稳定流动特征，所构造的高精度差分格式（高于三阶精度），分析了各种高精度差分格式的数值行为特征和模拟小尺度物理结构、分辨非定常间断面的能力，重点分析了正确模拟多尺度物理结构及其非线性干扰对数值方法的要求。第二部分是物理问题的直接数值模拟：根据可压缩湍流的流动物理特征，所建立的求解可压缩Navier-Stokes方程的高精度数值模拟方法，详细描述了不稳定流和可压缩湍流的直接数值模拟，以及在此基础上所发现的一些新的物理现象。直接数值模拟主要针对典型可压缩湍流，包括均匀各向同性湍流、槽道湍流、平面混合流、射流、平板边界层湍流和钝楔、钝锥边界层湍流等，重点是可压缩湍流从层流转捩到湍流的直接数值模拟及其流动机理的研究。书中还介绍了我课组所研制的高精度、高效并行算法的软件。

Investigations of the characteristics and mode of action of an algalytic bacterium isolated from Tai Lake

An algalytic bacterium provisionally designated as TL1 was isolated from Tai Lake, a large freshwater lake in the Yangtze Delta plain on the border of the Jiangsu and Zhejiang provinces and close to Wuxi city in the People's Republic of China. Strain TL1 was identified as Achromobacter sp. based on its biophysical and biochemical properties and the analysis of its 16S rRNA sequence. Microcystis aeruginosa, which is the most common toxic cyanobacterium in eutrophic freshwater, could be decomposed by strain TL1. The results showed that after inoculation with the algalytic bacterium, the content of chlorophyll-a, maximum PSII quantum yield, and maximum electron transport rates of the alga decreased sharply. At first, the algal cells enhanced the activities of some antioxidative enzymes, but subsequently, the activities of antioxidative enzymes fell sharply once damage of the algal cells was achieved. The filtrate from strain TL1 culture suspension, after autoclaving and treatments with proteinase K, strongly inhibited algal growth, indicating that the lytic metabolites were extracellular and thermostable, not a protein.

Fucoidan inhibits the development of proteinuria in active Heymann nephritis

Fucoidan, the sulphated polysaccharide extracted from brown seaweed, has various biological activities. The effect of fucoidan on the formation of proteinuria and renal functions in active Heymann nephritis was investigated in this study. Active Heymann nephritis was induced by administering brush border protein of rat proximal uriniferous tubules (FX1A). Fucoidan was administered by oral intubation to Heymann nephritis rats at three doses (50, 100 and 200 mg/kg) once daily for 4 weeks. The elevated urinary protein excretion and plasma creatinine due to the induction of Heymann nephritis were significantly reduced by fucoidan at doses of 100 and 200 mg/kg. The results indicated that fucoidan has a renoprotective effect on active Heymann nephritis and is a promising therapeutic agent for nephritis. Copyright (c) 2005 John Wiley F Sons, Ltd.

The boundary of palaearctic and oriental realms in western China

In the world-wide zoogeographic division, there has been no consentaneous understanding about the delimitation between palaearctic and oriental realms in western China. In this study, we will discuss the division based on amphibian distribution in Shaanxi, Gansu, Sichuan, Yunnan, and Tibet according to species coefficient similarity between each zoogeographic province. The results show that the northern border lies from Qinling Mountains-Feng Xian (Shaanxi)-Debu (Gansu)-Aba (Sichuan)-Batang-Bomi (Tibet), to Linzhi districts, and the southern border is from Taibai-Feng Xian in Shaanxi-Wen Xian (Gansu)-Songpan-Kangding-Daocheng (Sichuan), to Zhongdian-Gongshan in Yunnan, and westward to Motuo and Bomi district in Tibet. (c) 2008 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.

An inventory of forest relicts in the pastures of Southern Tibet (Xizang AR, China)

An inventory of isolated tree stands surrounded by desert pastures in Southern Tibet (A.R. Xizang, China) revealed more than 50 sites with vigorous trees of Juniperus convallium Rehder & E.H. Wilson and Juniperus tibetica Kom and additional more than 10 records where juniper trees had been destroyed between 1959-1976. The tree stands are not restricted to any specific habitat, and occur within an area stretching 650 km westwards from the current forest border of Southern Tibet. The trees are religious landmarks of the Tibetan Buddhists. The highest trees were found at an elevation of 4,860 m. Vegetation records, rainfall correlations and temperature data collected by local climate stations and successful reforestation trials since 1999 indicate that forest relicts fragmented through human interference could regenerate if current cattle grazing and deforestation practices are halted. The drought line of Juniperus forests in Southern Tibet is approximately 200-250 mm/a. A first pollen diagram from Lhasa shows forest decline associated with the presence of humans since at least 4,600 yr BP. The currently degraded commons developed in the last 600 yr. To date, no findings of remains of ancient forests in the Central Tibetan Highlands of the Changtang have been reported.

一种新型并联机器人工作空间分析

对一种新型并联机器人的工作空间问题作了讨论,基于运动学逆解,通过极限边界数值搜索算法求取了并联机器人工作空间,并通过MATLAB仿真得到了该并联机器人工作空间的实体模型。

大港油田复杂断块油气藏评价技术研究与应用

In this paper, in view of characteristics and appraisal difficulty of complicate fault block reservoir, based on the theory of reservoir geology, tectonic geology, sequence stratigraphy, logging geology and sedimentology, according to related multidisciplinary data, such as geological, geophysical, logging and testing, taking 3D seismic acquisition processing, delicate structure interpretation, fine reservoir prediction, reservoir engineering and logging evaluation as research methods, on the basis of comprehensive geologic research, innovative appraisal thinking of complicate fault block reservoir is probed into, reservoir evaluation technology series of different reservoirs were created, and appraisal circuit of complicate fault block reservoir was proposed. According to the research on main controlling factors of hydrocarbon and concentration and concealing laws of Dagang exploration area, family assemble patterns of complicate fault block reservoir were proposed firstly, such as twinning, juxtaposed, overlying, concurrent, connected in series and so on, so theory basement was provided to reservoir evaluation. Taking into account of difficulties of low signal to noise ratio and border identification of lithologic trap of complicate fault block reservoir, in the middle of seismic data acquisition, double focusing layout and optimization technology were adopted, geophysical model was set up, and best observation system was ascertained. During object processing, matching processing technology of removing time difference, phase difference, energy difference and frequency spectrum difference generated by different blazing and receiving elements was studied. Imagery, low amplitude structure and identification of subtle lithologic reservoir was interpreted reasonably. On the basis of characteristics and technical description analysis of structural, structural--lithologic and lithologic reservoirs, innovative appraisal thinking of these reservoirs was formatted, appraisal circuit of complicate fault block reservoir was proposed, and this method could be used in other similar oilfields