梅子垭水库生态因子场的分形特征

水生态系统由于多了一层水的介质以及水生生物较短的生命周期，使得其生态格局描述相对困难，对其进行定量描述的工作也相对较少。作为一个初步探索，分别应用非线性科学中的分形理论，对梅子垭水库的典型理化因子的生态因子场的水平的2维空间格局进行了分析，确定各浓度的稳定程度。

分形理论对水生态系统空间格局研究初探

首先对分形理论在生态学中的应用情况作了简要介绍，然后应用它对梅子垭水库的藻类叶绿素a浓度场水平2维空间格局进行了分析，通过对不同时间各浓度轮廓线的空间占据能力进行比较分析，确定了各浓度的稳定程度。可由此说明浮游植物的变化情况和生长潜力。

三峡科技移民示范区及其毗邻地区水体营养状况的数量分析

对在梅子垭及其毗邻地区若干重要水体所取的10个水样及其pH值、总氮、总磷、PO3-4态磷和P2O5态磷进行了聚类和主成分分析。聚类分析表明10个水样可分为两大类，其中一类又明显分为两类。主成分分析表明磷对第一主成分的贡献最大；氮对第二主成分的贡献最大，其值为负表示存在负相关，排序时将会影响水样在第二主成分上的排列方向。

长江流域若干水体寡毛类区系组成及相似性分析

研究了长江流域十余个水体水栖寡毛类的区系组成及分布。共鉴定水栖寡毛类53种，隶3科27属，其中仙女虫科15属31种(占58.49%)；颤蚓科11属20种(占37.74%)；线蚓科1属2种(占3.77%)。在河流、草型湖泊和藻型湖泊这三类水体中，以草型湖泊的物种数最多，达36种；其次为长江干流，34种；藻型湖泊仅24种。对寡毛类的种间关系及不同生境寡毛类种类组成的相似性进行了聚类分析，结果表明，寡毛类的种类分布具有明显的地域性，据此可将其划分为6类(A—F组)。

三峡大坝截流前后长江中上游江段水化学特性的初步调查

1997—1998年，在三峡大坝截流前后，对长江中上游地区十多个江段及若干个支流进行了多次的水质监测分析。结果表明：长江中上游水资源丰富，但污染较严重。从多项数据指标分析结果和多项资料表明，目前污染源主要为沿江工业和城市生活污水。长江干流污染远高于支流(嘉陵江除外)。而大江截流对长江中上游的水质近期影响较小，可以忽略不计。

长江中下游地区若干湖泊水质的多元分析与比较

1996年11月—1998年11月，对鄱阳湖等长江中下游若干浅水湖泊进行了水化学分析，并进行了主要水质指标(包括透明度、pH值、总氮、总磷、氨氮和硝酸盐等)的季节变动规律，并对这些指标进行了方差分析。结果表明：不同利用方式的水体间除硬度、碱度和T-N在几个湖区间的差异较小外，其它各项指标的差异均较显著；季节间除硬度、碱度、Ca、Mg和T-P外，其余各项指标在季节间的差异均较显著，说明其季节变动均不稳定。

水库网箱中加州鲈鱼生长的研究

在三峡库区一水库内利用诱食剂引诱小型鱼类，为网箱中的加州鲈鱼提供天然饵料，以观测加州鲈鱼的生长情况。通过剪鳍标记方法，把三口网箱中的加州鲈鱼分为六个平行组和一个对照组，平行组的加州鲈鱼掠食被诱食剂引诱进入网箱的小型鱼类，而对照组的则摄食投喂足够数量的小型鱼类。结果表明：(1)平行组和对照组间加州鲈鱼的生长差异不显著；(2)加州鲈鱼的生长是逐渐增大的，生长速率时快时慢，并且呈日趋减缓态势：(3)实验结束时的体重比实验前平均增加了494.1%，平均日增重7.4%；(4)加州鲈鱼的体重与生长时间呈线性关系，生长

The search for the IFN-gamma receptor in fish: Functional and expression analysis of putative binding and signalling chains in rainbow trout Oncorhynchus mykiss

Interferons (IFNs), consisting of three major subfamilies, type I, type II (gamma) and type III (lambda) IFN, activate vertebrate antiviral defences once bound to their receptors. The three IFN subfamilies bind to different receptors, IFNAR1 and IFNAR2 for type I IFNs, IFN gamma R1 and IFN gamma R2 for type II IFN, and IL-28R1 and IL-10R2 for type III IFNs. In fish, although many types I and II IFN genes have been cloned, little is known about their receptors. In this report, two putative IFN-gamma receptor chains were identified and sequenced in rainbow trout (Oncorhynchus mykiss), and found to have many common characteristics with mammalian type II IFN receptor family members. The presented gene synteny analysis, phylogenetic tree analysis and ligand binding analysis all suggest that these molecules are the authentic IFN gamma Rs in fish. They are widely expressed in tissues, with IFN gamma R1 typically more highly expressed than IFN gamma R2. Using the trout RTG-2 cell line it was possible to show that the individual chains could be differentially modulated, with rIFN-gamma and rIL-1 beta down regulating IFN gamma R1 expression but up regulating IFN gamma R2 expression. Overexpression of the two receptor chains in RTG-2 cells revealed that the level of IFN gamma R2 transcript was crucial for responsiveness to rIFN-gamma, in terms of inducing gamma IP expression. Transfection experiments showed that the two putative receptors specifically bound to rIFN-gamma. These findings are discussed in the context of how the IFN gamma R may bind IFN-gamma in fish and the importance of the individual receptor chains to signal transduction. (c) 2009 Elsevier Ltd. All rights reserved.

Clonal diversity and genealogical relationships of gibel carp in four hatcheries

To conserve and utilize the genetic pool of gynogenetic gibel carp (Carassius auratus gibelio), the Fangzheng and Qihe stock hatcheries have been established in China. However, little information is available on the amount of genetic variation within and between these populations. In this study, clonal diversity in 101 fish from these two stock hatcheries and 35 fish from two other hatcheries in Wuhan and Pengze respectively was analysed for variation in serum transferrin. Thirteen clones were found in Fangzheng and Qihe, of which 12 were novel. Six clones were specific to Fangzheng and three specific to Qihe, whereas four were shared among the Fangzheng and Qihe fish. To obtain more knowledge on genetic diversity and genealogical relationships within gibel carp, the complete mitochondrial DNA (mtDNA) control region (similar to 920 bp) was sequenced in 64 individuals representing all 14 clones identified in the four hatcheries. Differences in the mtDNA sequences varied remarkably among hatcheries, with the Fangzheng and Qihe lines demonstrating high diversity and Wuhan and Pengze showing no variation. The Fangzheng and Qihe lines might represent two distinct matrilineal sources. One of the Qihe samples carried the haplotype shared by a most widely cultivated Fangzheng clone, indicating that a Fangzheng clone escaped from cultivated ponds and moved into the Qihe hatchery. Four Fangzheng samples clustered within the lineage formed mainly by Qihe samples, most likely reflecting historical gene flow from Qihe to Fangzheng. It is suggested that clones in Wuhan originated from Fangzheng, consistent with their introduction history, supporting the hypothesis that gibel carp in Pengze were domesticated from individuals in the Fangzheng hatchery.

Genetic structure of Chinese sucker population Myxocyprinus asiaticus in the Yangtze River based on mitochondrial DNA marker

The sequencing analysis of the mitochondrial DNA control region (mtCR DNA) was performed to assess the genetic divergence and population structure of the Chinese sucker Myxocyprinus asiaticus (Cypriniformes Catostomidae) using four sample lots from natural populations of the Yangtze River. The mtCR DNA sequences of approximately 920 base pairs were obtained. A total of 223 nucleotide positions were polymorphic, and these defined 39 haplotypes. Of the 39 haplotypes, 37 (90%) were not shared, and among the populations as a whole there was little sharing of haplotypes. The average haplotype diversity (0.958) and the average nucleotide diversity (0.052) indicated a higher level of genetic diversity of Chinese sucker through the river. Analysis of molecular variation (AMOVA) of data revealed significant partitioning of variance (P<0.001) among populations (60.29%), and within populations (39.71%). The topology according to the neighbor joining and maximum parsimony methods showed mosaic composition of the 39 haplotypes, suggesting that the populations wore not completely divergent. The pairwise F statistic values, however, indicated that the population structuring existed to some extent among the geographic populations. There was a positive relationship between the aquatic distance and the genetic distance (Fst) among the populations (P<0.05). Based on our data, it is suggested that genetic drift, gene flow, and stochastic events are the possible factors influencing the population structure and genetic variation.

Optical modulator based on a Si0.75Ge0.25/Si/Si0.5Ge0.5 asymmetric superlattice structure

An optical modulator is designed and fabricated based on a Si0.75Ge0.25/Si/Si0.5Ge0.5 asymmetrical superlattice structure. The device comprises a p-i-n diode made on the asymmetrical superlattice integrated with a 920-mu m-long Fabry-Perot (F-P) cavity. Parameters of the rib waveguide are designed to satisfy only the fundamental-TE mode transmission. Here, 65 and 40-pm red shifts of the peak resonant were measured under the applied bias of 2.5 and -32.0 V, respectively. The analysis shows that, besides the thermal-optical and plasma dispersion effects, the Pockels effect also contributes to such a peak shift. The corresponding calculated effective Pockels coefficient is about 0.158 pm/V.

Epitaxial Growth of AlInGaN Quaternary Alloys by RF-MBE

AlInGaN quaternary alloys were successfully grown on sapphire substrate by radio-frequency plasma-excited molecular beam epitaxy (RF-MBE). AlInGaN quaternary alloys with different compositions were acquired by changing the Al cell's temperature. The streaky RHEED patterns were observed during AlInGaN quaternary alloys growth. Scanning Electron Microscope (SEM), Rutherford back-scattering spectrometry (RBS), X-Ray diffraction (XRD) and Cathodoluminescence (CL) were used to characterize the structural and optical properties of the AlInGaN alloys. The experimental results show that the AlInGaN quaternary alloys grow on the GaN buffer in the layer-by-layer growth mode. When the Al cell's temperature is 920 degrees C, the Al/In ratio in the AlInGaN quaternary alloys is about 4.7, and the AlInGaN can acquire better crystal and optical quality. The X-ray and CL full-width at half-maximum (FWHM) of the AlInGaN are 5arcmin and 25nm, respectively.

Light extraction of GaN LEDs with 2-D photonic crystal structure

Ultraviolet photo-lithography is employed to introduce two-dimensional (2D) photonic crystal (PC) structure on the top surface of GaN-based light emitting diode (LED). PC patterns are transferred to 460-nm-thick transparent indium tin oxide (ITO) electrode by inductively coupled plasma (ICP) etching. Light intensity of PC-LED can be enhanced by 38% comparing with the one without PC structure. Rigorous coupled wave analysis method is performed to calculate the light transmission spectrum of PC slab. Simulation results indicate that total internal reflect angle which modulated by PC structure has been increased by 7 degrees, which means that the light extraction efficiency is enhanced outstandingly.

10 Gbit s(-1) electroabsorption-modulated laser light-source module using selective area MOVPE

A distributed-feedback (DFB) laser and a high-speed electroabsorption (EA) modulator are integrated, on the basis of the selective area MOVPE growth (SAG) technique and the ridge waveguide structure, for a 10 Gbit s(-1) optical transmission system. The integrated DFB laser/EA modulator device is packaged in a compact module with a 20% optical coupling efficiency to the single-mode fibre. The typical threshold current is 15 mA, and the side-mode suppression ratio is over 40 dB with the single-mode operation at 1550 nm. The module exhibits 1.2 mW fibre output power at a laser gain current of 70 mA and a modulator bias voltage of 0 V. The 3 dB bandwidth is 12 GHz. A dynamic extinction ratio of over 10 dB has been successfully achieved under 10 Gbit s(-1) non-return to zero (NRZ) operation, and a clearly open eye diagram is obtained.

A Novel Architecture of Vision Chip for Fast Traffic Lane Detection and FPGA Implementation

This paper presents a novel architecture of vision chip for fast traffic lane detection (FTLD). The architecture consists of a 32*32 SIMD processing element (PE) array processor and a dual-core RISC processor. The PE array processor performs low-level pixel-parallel image processing at high speed and outputs image features for high-level image processing without I/O bottleneck. The dual-core processor carries out high-level image processing. A parallel fast lane detection algorithm for this architecture is developed. The FPGA system with a CMOS image sensor is used to implement the architecture. Experiment results show that the system can perform the fast traffic lane detection at 50fps rate. It is much faster than previous works and has good robustness that can operate in various intensity of light. The novel architecture of vision chip is able to meet the demand of real-time lane departure warning system.