钒多糖络合物的制备方法及其应用

本发明涉及一种海藻多糖与钒络合形成海藻多糖钒络合物及制备方法。与酸性多糖形成络合物的制备方法：将酸性海藻多糖或其衍生物溶解于去离子水中，加入VOSO4溶液，搅拌反应，反应结束后加入乙醇沉降，过滤，洗涤，干燥，粉碎，得到钒多糖络合物；与中性多糖及其衍生物形成络合物的制备方法：将海藻多糖溶解于去离子水中，调节pH值为碱性，保持反应液pH值为碱性，沉降，过滤，将滤饼干燥，粉碎，即得钒多糖络合物。本发明优点是：一、海藻多糖本身具有多种药理作用；二、充分发挥微量元素和多糖的生理活性，使两者的作用相互协调并增强；三、将无机钒转化为多糖有机钒，可以大大降低钒的毒性，提高钒的生物可利用性。

Degradation of tropical forest in Hainan, China, 1991-2008: Conservation implications for Hainan Gibbon (Nomascus hainanus)

The Hainan gibbon (Nomascus hainanus) is one of the most endangered primates in the world, confined to mature natural forest in Hainan Island, China. We assessed changes in habitat condition on the island between 1991 and 2008, using vegetation maps generated by remote-sensing images. We defined forest suitable for gibbons based on composition, tree size and canopy cover. During the 17-year period, the area of suitable gibbon forest decreased by 540 km(2) (35%) across the whole island, and by 6.3 km(2) (7%) in the locality of the sole remaining gibbon population at Bawangling National Nature Reserve. The forest patches large enough (>1 km(2)) to support a gibbon group decreased from 754 km(2) to 316 km(2) in total area, and from 92 to 64 in number. Suitable natural forest was mainly replaced by plantations below 760 m, or degraded by logging, grazing and planting of pines above 760 m. Meanwhile, forests in former confirmed gibbon areas became more fragmented: mean area of patches decreased by 53%. We mapped the patches of natural forest in good condition which could potentially support gibbons. We recommend a freeze on further expansion of plantations between core patches at Bawangling, Jiaxi-Houmiling and Yinggeling Nature Reserves in accordance with forest protection regulations; establishment of nature reserves in currently unprotected natural forest patches elsewhere in line with the local government's nature reserve expansion policy; and active natural-forest restoration between remaining fragments at Bawangling. (C) 2010 Elsevier Ltd. All rights reserved.

Suitable sites for sustainable aquaculture development in Mymensingh, Bangladesh: A GIS methodological perspective

A GIS study was carried out to find out the sites suitable for aquaculture in Mymensingh region. A number of criteria were selected for GIS modeling followed by the approach of Kapetsky (1994). The criteria were developed from a range of existing data sources such as, surface and underground water level, availability of feed ingredients and animal wastes, sources of fish fry, market facilities, extension support and communication facilities for aquaculture development. The data were located, collected and compiled from different GOs and NGOs located in the region along with primary data from the field survey wherever necessary and then prepared for computer analyses. Using the database, a series of GIS models were developed in order to ascertain and prioritize the most suitable areas for aquaculture development in the region. Out of total 407,528 ha available lands in the region, the study identified 99,415 ha very suitable and 302,754 ha moderately suitable for aquaculture promotion. Result of the study is indicative to the modeling power of GIS for aquaculture application and could be used to refine the models in future, particularly if it is supported with further detail field data. To get a more concrete and complete model, detailed study should be made available on the availability of mustard oil cake, rice bran, wheat bran, and usable animal and urban wastes that could be used as low-cost feed for sustainable aquaculture.

Origination of an X-linked testes chimeric gene by illegitimate recombination in Drosophila

The formation of chimeric gene structures provides important routes by which novel proteins and functions are introduced into genomes. Signatures of these events have been identified in organisms from wide phylogenic distributions. However, the ability to

云南省澜沧江自然保护区鸟类资源调查

2005年3～4月,对云南省临沧地区澜沧江自然保护区的鸟类资源进行了调查.通过观察和网捕调查,共计采集记录105种鸟类.结合中国科学院昆明动物研究所鸟类标本室收藏的临沧地区的207种鸟类标本,以及该地区的有关文献资料记录的84种,保护区内共有396种鸟类,隶属55 科(另4亚科)19 目,占云南省所录鸟类种数848种的47%,全国鸟类种数1331种的30%.其中国家一级保护物种2种,二级保护物种39种.保护区内记录的鸟类有留鸟307种,占所录鸟类的78%.区系成分以东洋界物种为主,有292种,占繁殖鸟类总种数的83%.亚区级区系分析表明保护区内的鸟类以滇南山地亚区和西南山地亚区的种类为主,前者成分稍多于后者,说明该地区处于由滇南山地亚区向西南山地亚区过渡的地带.结合该区鸟类垂直分布的特点,提出应加强对原生及次生阔叶林的保护,尤其是对成熟次生林的保护,因为它们对保存该保护区的大多数物种具有重要的价值.

稳定的RNA 发夹结构在人类88 个mRNA 编码区中的分布

　以UNCG, GNRA , CUU G (N = A , U , C 或G; R = G或A) 为端环能够形成稳定的、保 守的发夹结构. 它们具有特殊的结构特征, 并在体内发挥着重要的生物学功能. 这些稳定的发夹 广泛分布于体内rRNA , 催化RNA 和非编码mRNA 中. 但对人类88 个编码区mRNA 二级结构的 研究当中, 却没有发现C(UUCG) G发夹. 而且, 与rRNA 不同, 这些编码区mRNA 四环序列的 分布没有明显的偏好性.

Stress on the ward: evidence of safety tipping points in hospitals

Do hospitals experience safety tipping points as utilization increases, and if so, what are the implications for hospital operations management? We argue that safety tipping points occur when managerial escalation policies are exhausted and workload variability buffers are depleted. Front-line clinical staff is forced to ration resources and, at the same time, becomes more error prone as a result of elevated stress hormone levels. We confirm the existence of safety tipping points for in-hospital mortality using the discharge records of 82,280 patients across six high-mortality-risk conditions from 256 clinical departments of 83 German hospitals. Focusing on survival during the first seven days following admission, we estimate a mortality tipping point at an occupancy level of 92.5%. Among the 17% of patients in our sample who experienced occupancy above the tipping point during the first seven days of their hospital stay, high occupancy accounted for one in seven deaths. The existence of a safety tipping point has important implications for hospital management. First, flexible capacity expansion is more cost-effective for safety improvement than rigid capacity, because it will only be used when occupancy reaches the tipping point. In the context of our sample, flexible staffing saves more than 40% of the cost of a fully staffed capacity expansion, while achieving the same reduction in mortality. Second, reducing the variability of demand by pooling capacity in hospital clusters can greatly increase safety in a hospital system, because it reduces the likelihood that a patient will experience occupancy levels beyond the tipping point. Pooling the capacity of nearby hospitals in our sample reduces the number of deaths due to high occupancy by 34%.

Shape vs. volume: Invariant shape descriptors for 3D region of interest characterization in MRI

We propose a new approach for quantifying regions of interest (ROIs) in medical image data. Rotationally invariant shape descriptors (ISDs) were applied to 3D brain regions extracted from MRI scans of 5 Parkinson's patients and 10 control subjects. We concentrated on the thalamus and the caudate nucleus since prior studies have suggested they are affected in Parkinson's disease (PD). In the caudate, both the ISD and volumetric analyses found significant differences between control and PD subjects. The ISD analysis however revealed additional differences between the left and right caudate nuclei in both control and PD subjects. In the thalamus, the volumetric analysis showed significant differences between PD and control subjects, while ISD analysis found significant differences between the left and right thalami in control subjects but not in PD patients, implying disease-induced shape changes. These results suggest that employing ISDs for ROI characterization both complements and extends traditional volumetric analyses. © 2006 IEEE.

基于S6K1基因部分序列的鲤科鱼类系统发育关系及内含子1Indel位点分析

鲤科鱼类在东亚分布广泛且数量丰富,在物种演化上具有重要的系统发育地位.本研究基于S6K1基因5′端功能调控序列,通过PCR扩增、克隆和测序,共获得30种鱼类S6K1前端部分DNA序列(外显子1,外显子2及内含子1),对序列变异进行分析,并采用邻接法(NJ)、最大简约法(MP)、最大似然法(ML)和贝叶斯法(Bayesian)重建鲤科鱼类系统发育关系.亚口鱼科的胭脂鱼(Myxocyprinus asiaticus)作为外类群,通过4种方法所得系统发育分支图大致相同,均以较高的节点支持率支持雅罗鱼系和鲃系的划

梁子湖湿地植物多样性现状与评价

根据1999~2001年的野外调查数据,研究了湖北梁子湖湿地浮游藻类和高等植物多样性资源.结果表明,该湿地常见浮游藻类73种,隶属于7门58属(绿藻28种,硅藻19种,蓝藻14种,金藻4种,裸藻3种,甲藻3种,隐藻2种);高等植物282种,隶属于72科183属(苔藓8种,蕨类9种,裸子植物3种,被子植物262种),其中国家重点保护野生植物5种.浮游藻类密度和生物量均值分别为(1163.79913.51)104cell/L和6.1342.737mg/L,叶绿素a含量12.754.98mg/L,浮游藻类表层日

Study on freshwater genus Peridinium (Dinophyta) from China

Peridinium is an important genus of freshwater armoured dinoflagellates with two more intercalary plates (sensu Bourrelly). A few species of Peridinium were known from China heretofore. The plate pattern is one of the important criteria for the taxonomy of Peridinium, and it was difficult to visualize their plate patterns under normal light microscope. For editing of Flora Algarum Sinicarum Aquae Dulcis, 11 species of Peridinium collected from various freshwater habitats of China are described. Among them, 6 species are first reported from China. They are P. gatunense Nygaard, P. gutwinskii Woloszynska, P. lomnickii Woloszynska, P. palatinum Lauterborn, P. striolatum Playfair, and P. zonatum Playfair. Epifluorescence microscopy and scanning electron microscopy, and also light microscopy were employed for their structure and patterns of thecal plates.