杜鹃花属(Rhododendron)种间亲缘关系及小枝异速生长分析

杜鹃花属(Rhododendron)植物种间有着丰富的遗传变异，表型变异并不能完全或真实地反映遗传变异，需要利用信息大分子(DNA)的变化来评价其亲缘关系及系统发育。当年生小枝作为一个独立的构件单元，是植物体上最有活力的部分之一，具有重要的生态学意义。本文以杜鹃为材料，首先全面分析了杜鹃花属种间亲缘关系和小枝功能性状间的关系(异速生长)，然后对小枝水平功能属性间的关系进行系统独立比较分析研究，同时验证小枝异速生长关系。 选取23种杜鹃花属植物为材料，利用ISSR分子标记手段对其种间的亲缘关系进行研究和评价，结果发现：1) ISSR位点变异丰富。通过10条ISSR随机引物对供试的混合DNA样品进行分析，共检测到207个标记，其中多态性标记为197个，多态百分率为95.17%，种间表现出丰富的遗传多样性;2) 对ISSR产物进行统计分析的聚类分析结果同传统分类的结果基本一致。说明，ISSR分子标记技术在构建系统发育树方面具有较高的成熟性和可靠性。 本研究还对42种杜鹃花属植物小枝的功能属性进行了异速生长分析，结果发现：1)小枝大小对叶片生物量分配比率的影响不显著，SMA斜率为1.040 (95%的置信区间(CI)=0.998～1.085);但是，小枝越大，叶柄生物量分配比例越高(SMA斜率为1.245，显著大于1.0，呈显著的异速生长关系);2)小枝越小，单叶面积越小(支持Corner法则)，单位质量小枝所支持的叶面积越大，即具有较小枝条和较小叶片的物种可能具有较高的叶面积支持效率。结果有助于更好地理解亲缘关系十分接近的杜鹃花属植物，在不同生境条件下叶片大小的差异，以及在胁迫生境条件下小叶物种更为常见的原因。 此外，本文利用系统独立比较方法结合传统种间比较方法对23种杜鹃植物小枝进行异速生长分析，其中这23种杜鹃是前两方面研究的共有材料。系统独立比较分析分别依据ISSR得出的系统关系和中国植物志提供的系统关系构建两种系统树。结果表明：1)系统独立比较与种间比较分析得出的相关性结果一致;2)两种系统树所得的独立比较分析结果基本一致，相关性均达到极显著水平，即这两种方法作为构建系统树的依据是一致的。

Effect of supplementary feed on the growth of shinghi (Heteropneustes fossilis Bloch)

Effect of two supplementary feed (food A and food B) on the growth of shinghi, Heteropneustes fossilis was observed for 3 months period during winter and summer. Food B containing rice bran 2 g, wheat bran 2 g and blood 10 ml, showed better growth. The net gain in length was 70.04 mm and in weight was 13.82 g. Total net production was observed as 254.00 g/m² with feed A and 345.50 g/m² with feed B.

Socio-economic conditions of the pond owners of Demra, Dhaka

On the basis of fish culture status 96 ponds of the study area were classified into 4 categories like wild stock (27%), extensive culture (24%), improved extensive culture (33%) and semi-intensive culture (16%). Percentage of small, medium and large ponds were 38, 44, and 18 respectively whereas education levels below SSC, below Bachelor and above were 43, 38 and 19 respectively and single owners belonged to 54% of the ponds. Per hectare yields of extensive, improved extensive and semi-intensive categories of culture were 1.3, 2.12 and 4.0 metric tons respectively and their net return were 46, 63 and 92 thousand taka respectively. Considering the problems of fish culture, multiple ownership was found to be the most important one.

Some observations on the performance of 10.5 m mid-water trawl operated off Veraval

The communication presents the results of fishing trials conducted off Veraval with a 10.5 m four-seam unequal paneled mid-water trawl with vertically curved otter boards. The design and structural details of net and otter boards are described in detail. Particulars such as the fish caught during experimentation, horizontal spread of the net as well as towing resistance offered in action are also incorporated.

Identification of support conditions of buried pipes using a vibrating pig

This paper describes a method for monitoring the variation in support condition of pipelines using a vibration technique. The method is useful for detecting poor support of buried pipelines and for detecting spanning and depth of cover in sub-sea lines. Variation in the pipe support condition leads to increased likelihood of pipe damage. Under roadways, poorly supported pipe may be damaged by vehicle loading. At sea, spanned sections of pipe are vulnerable to ocean current loading and also to snagging by stray anchors in shallow waters. A vibrating `pig' has been developed and tested on buried pipelines. Certain features of pipe support, such as voids and hard spots, display characteristic responses to vibration, and these are measured by the vibrating pig. Post-processing of the measured vibration data is used to produce a graphical representation of the pipeline support and certain `feature characteristics' are identified. In field tests on a pipeline with deliberately constructed support faults, features detected by the vibrating pig are in good agreement with the known construction.

Modelling of waterfront cantilever sheet pile walls subjected to earthquake loading

The seismic performance of waterfront cantilever sheet pile retaining walls is of continuing interest to geotechnical engineers as these structures suffer severe damage and even complete failure during earthquakes. This is often precipitated by liquefaction of the surrounding soil, either in the backfill or in front of the wall. This paper presents results from a series of small-scale plane strain models that were tested on a 1-g shaking table and recorded using a high-speed, high-resolution digital camera. The technique of Particle Image Velocimetry (PIV) was applied in order to allow the failure mechanisms to be visualised. It is shown that using PIV analyses it is possible to obtain failure mechanisms for a cantilever wall in liquefiable soil. These failure mechanisms are compared with those obtained for a cantilever wall in dry soil, previously carried out at a similar scale. It was observed that seismic liquefaction causes significant displacement in much larger zones of soil near the retaining wall compared to an equivalent dry case. The failure mechanism for a cantilever wall with liquefiable backfill, but with a remediated zone designed not to liquefy, is also presented and compared to the unremediated case.

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.

Modular Organization in a Cell: Concepts and Applications

Network biology is conceptualized as an interdisciplinary field, lying at the intersection among graph theory, statistical mechanics and biology. Great efforts have been made to promote the concept of network biology and its various applications in life s