Effect of two green algae species (Chlorella sp. & Scenedesmus obliquus) enriched with B group vitamins on food chain of Rutilus frisii kutum (Kamensky, 1901) fry

The Effect of two freshwater green algae species Chlorella sp. & Scenedesmus obliquus enriched (from the beginning of culture and after 96 hours) with different dosages of B group vitamins (0, 0.5, 1, and 2 ml of enriching solution per each liter of algae medium) on fecundity of Daphnia magna and growth of Rutilus frisii kutum fry were investigated in a research from spring, 2008 to autumn, 2009. First, each of the green algae species were cultured purely and massively in the Zander (Z-8+N) medium and then the nutritional value (the amount of protein, lipid, and carbohydrate) of enriched algae were meausered. In this study, enriching of Chlorella sp. & S. obliquus with a suitable mix of B group vitamins significantly improved their nutritive value. So the highest amount of nutritional value of Chlorella sp. was obtained because of enriching with dosage 0.5 ml.l-1 (366.654Kcal) and for Scenedesmus obliquus with dosage of 1 ml.l-1 (376.95Kcal). The acquired amount from control group showed an increase of respectively 42% and 11%. According to the results, increased dosages of enriching solution caused Daphnia fecundity to increase (at both stages : enrichment from the beginning of culture and after 96 hours). So the highest average of D. magna reproduction rate was obtained through being fed with Chlorella sp. and S. obliquus enriched with dosage of 2 ml enriching solution per liter of algae medium. The average fecundity of D. magna fed with Chlorella sp. enriched with dosage of 2 ml.l-1 enriching solution from the beginning of culture and after 96 hours was obtained respectively 2.128 ± 0.375 and 2.1 ± 0.69 and the average fecundity of D. magna fed with S. obliquus enriched with dosage of 2 ml enriching solution from the beginning of culture and after 96 hours was obtained respectively 2.128 ± 0.375 and 2.1 ± 0.69 which showed respectively an increase of 61 ٪, 91٪, 77 ٪, and 83٪ in proportion to the acquired amount from control group. When enriching solution was added to either algae culture medium from the beginning of culture, showed statistically significant differences (P<0.05) between dosages of 0 and 2 ml.l-1, 1 and 2 ml.l-1, and 0.5 and 2 ml enriching solution per each liter of Chlorella sp. culture medium and between dosages of 0 and 1 ml.l-1, and 0 and 2 ml enriching solution per each liter of S. obliquus culture medium. The highest average of body weight gain percentage and specific growth rate of kutum fry was obtained respectively 21.19%, 26.63%, 1.92, and 2.34 from the beginning of culture and after 96 hours with dosage of 1 ml B group vitamins per each liter of Chlorella sp. culture medium, which showed respectively an increase of 50%, 70%, 46%, and 62% in proportion to the acquired amount from control group. In the cases which Chlorella sp. were grown in the medium containing vitamin, from point of view of the average percentage of weight and specific growth rate of kutum fry significant differences were observed on the basis of the result of One-way ANOVA between dosages of 0 and 1, 1 and 2 , 0.5 and 1 ml B group vitamins per each liter. The highest average of body weight gain percentage and specific growth rate of kutum fry was obtained respectively 32.02%, 29.42%, 2.78, and 2.34 from the beginning of culture and after 96 hours with dosage of 2 ml B group vitamins per each liter of S. obliquus culture medium, which showed respectively an increase of 32%, 19%, 28%, and 17% in proportion to the acquired amount from control group. In the cases which S. obliquus were grown in the medium containing vitamin, from point of view of the average percentage of weight and specific growth rate of kutum fry significant differences were observed on the basis of the result of One-way ANOVA between dosages of 0 and 1, 0 and 2. According to the results of the present research we can say that considerable enhancement in the quality of the food of D. magna can be made by manipulation of the nutritional value of fresh water unicellular green algae with suitable mixture of B group vitamins, so that both the fecundity of D. magna will increase and the nutritional requirements of the kutum fry will be filled in this way.

Report of the Training Workshop on MPA Management Effectiveness Assessment Tool, Dhaka, Bangladesh, 27 and 29 April, 2015

Objectives of the workshop included; introduction to various Marine Protected Area (MPA) tools with a focus on Management Effectiveness Assessment Tool (MEAT); report on selected MPAs in Bangladesh; undertake initial assessments using MEAT; and develop workplans for other MPAs

Report of the MPA exposure visit to Malaysia, 29 March-02 April, 2015

The main objective of the visit was to share the success of Marine Protected Area (MPA) management in Malaysia with Bangladeshi counterparts, representatives of donor organizations, NGOs and researchers.

中国典型地带29种土壤纤毛虫记述(纤毛门:动基片纲)

记述了在中国６个典型地带土壤中鉴定到的隶属于动基片纲的２９种纤毛虫，其中５种为中国土壤原生动物新记录种．这些种类是：陆生拟裸口虫，恼斜板虫，吻瓶口虫，双核管形虫，琴刀口虫，长刀口虫，长尾刀口虫，斜叶苔叶虫，神螺流苏虫，土壤肾形虫，三分肾形虫，背沟肾形虫，无规肾形虫，直立肾形虫，粗糙拟肾形虫，莫氏拟肾形虫，贪食阔庭虫，大撕拉虫，吻吴氏虫，澳洲吴氏虫，大口匙口虫，尖锐密粒虫，卡氏颠毛虫，小拟匙口虫，尖锐篮环虫，丛林拟篮环虫，有肋薄咽虫，弧形微秀体虫和凤冠齿扇虫．

Crustacean zooplankton distribution patterns and their biomass as related to trophic indicators of 29 shallow subtropical lakes

A comparative limnological study was carried out to present a snapshot of crustacean zooplankton communities and their relations to environmental factors to test whether there is a consistent relationship between crustacean biomass and trophic indicators among lake groups with similar trophic conditions. The study lakes showed a wide range of trophic status, with total phosphorus (TP) ranging from 0.008 to 1.448mgL(-1), and chlorophyll a from 0.7 to 146.1 mu g L-1, respectively. About 38 species of Crustacea were found, of which Cladocera were represented by 25 taxa (20 genera), and Copepoda by 13 taxa (I I genera). The most common and dominant species were Bosmina coregoni, Moina micrura, Diaphanosoma brachyurum, Cyclops vicinus, Thermocyclops taihokuensis, Mesocyclops notius and Sinocalanus dorrii. Daphnia was rare in abundance. Canonical correspondence analysis showed that except for four species (D. hyalina, S. dorrii, C. vicinus and M. micrura), almost all the dominant species had the same preference for environmental factors. Temperature, predatory cyclopoids and planktivorous fishes seem to be the key factors determining species distribution. TP was a relatively better trophic indicator than chlorophyll a to predict crustacean biomass. Within the three groups of lakes, however, there was no consistent relationship between crustacean biomass and trophic indicators. The possible reason might be that top-down and bottom-up control on crustaceans vary with lake trophic state. The lack of significant negative correlation between crustacean biomass and chlorophyll a suggests that there was little control of phytoplankton biomass by macrozooplankton in these shallow subtropical lakes. (c) 2007 Elsevier GmbH. All rights reserved.

Metamorphic growth of 1.25-1.29 mu m InGaAs quantum well lasers on GaAs by molecular beam epitaxy

We demonstrate 1.25-1.29 mu m metamorphic laser diodes grown on GaAs by molecular beam epitaxy (MBE) using an alloy-graded buffer layer (GBL). Use of Be in the GBL is effective to reduce surface/interface roughness and improves optical quality. The RMS surface roughness of the optimized metamorphic laser is only two atomic monolayers for 1 x 1 mu m(2). Cross-sectional transmission electron microscopy (TEM) images confirm that most dislocations are blocked in the GBL. Ridge waveguide lasers with 4 mu m wide ridge were fabricated and characterized. The average threshold current under the pulsed excitation is in 170-200 mA for a cavity length of 0.9-1.5 mm. This value can be further reduced to about 100 mA by high-reflectivity coating. Lasers can work in an ambient temperature up to at least 50 degrees C. (c) 2006 Elsevier B.V. All rights reserved.

Smaller Ge Quantum Dots Obtained by ArF Excimer Laser Annealing

Ge self-assembled quantum dots (SAQDs) are grown with a self-assembled UHV/CVD epitaxy system. Then,the as-grown Ge quantum dots are annealed by ArF excimer laser. In the ultra-shot laser pulse duration,～20ns, bulk diffusion is forbidden, and only surface diffusion occurs, resulting in a laser induced quantum dot (LIQD). The diameter of the LIQD is 20～25nm which is much smaller than the as-grown dot and the LIQD has a higher density of about 6 × 10~(10)cm~(-2). The surface morphology evolution is investigated by AFM.

增益钳制半导体光放大器波长转换的研究

数值模拟了增益钳制SOA(GC-SOA)的波长转换过程,分析了GC-SOA实现波长转换的原理.首次发现了GC-SOA波长转换中类似接通延迟的现象,这种现象将限制GC-SOA在高速波长转换中的应用.

Measurement of Cavity Loss and Quasi-Fermi-Level Separation for Fabry-Perot Semiconductor Lasers

A fitting process is used to measure the cavity loss and the quasi-Fermi-level separation for Fabry- Perot semiconductor lasers. From the amplified spontaneous emission (ASE) spectrum, the gain spectrum and single-pass ASE obtained by the Cassidy method are applied in the fitting process. For a 1550nm quantum well InGaAsP ridge waveguide laser, the cavity loss of about ～24cm~(-1) is obtained.

BF＋对（29）Si＋注入GaAs层的影响

于2010-11-23批量导入

阔叶红松林碳循环及细根与凋落物生产、分解研究

森林凋落物、细根及红松阔叶林碳循环 摘要: 由于全球变化进程的加快使生态系统碳循环在科学研究中的重要性日益突出。森林生态系统作为陆地生态系统的一个重要组成部分，其碳循环过程和源、汇功能一直是人们研究的热点。本文以森林生态系统物质循环的两个关键过程－凋落物和细根的生产和分解过程为主要研究目标，探讨了两者的时空动态格局和主驱动因子；同时采用传统的森林调查与通量观测相结合的方法，系统的刻画了红松阔叶林生态系统的碳循环过程。 主要结论如下：（1）区域平均温度是决定东北地区不同气候区域森林凋落量发生变化的主要因素，优势树种生物学特性不同导致同一气候区域内森林类型之间凋落量呈现显著差异。（2）红松阔叶林不同凋落组分凋落量对气候因子的年际波动和林分生长的反应不同，红松生长使其落叶量和在凋落总量中所占的比重显著增加，这将导致林地的凋落物组成和物理化学性质发生根本改变。（3）6个不同气候区域内地带性树种凋落物分解率和养分元素释放率随纬度增加而降低，并且与区域年平均温度和降水量呈显著正相关关系，随着分解的进行凋落物分解率与温度和降水的相关性降低。凋落物初始化学指标与其分解率呈显著相关关系。回归模型的预测结果显示温度和降水的增加均可促进凋落物分解，并且其对分解的影响强度大于CO2浓度升高对凋落物分解间接影响。（4）3种原始群落——红松阔叶林，云冷杉林和岳桦林的细根生产量、周转率和养分元素归还量随着海拔的升高而降低，对于同一海拔带上的3种林型而言，红松阔叶林生长量最高而周转率和养分元素释放率最低，白桦纯林细根周转率和养分元素释放率最高，山杨林细根生长量最小，细根周转率和养分元素释放率介于前两者之间。（5）红松阔叶林生态系统碳储量为25962.17±2002.1 C g m-2，其中植物（乔、灌木和草本）、土壤和林地（凋落物和倒木）内的碳储量占总体的79%, 15% 和6%。生态系统碳的净交换(NEE)为366.8±110.6 C g m-2year-1, 林地和土壤的碳输入量为504.9±28.9 C g m-2year-1，输出量为405.9±28.7 C g m-2year-1。植物净固碳量为287±34.5 C g m-2year-1，乔木和灌木净固碳量分别占植物净固碳总量的98.6％和1.4％。 关键词：森林凋落物，凋落物分解，细根，碳储量，碳循环

~(29)S双质子的同时发射

<正>近年来,双质子发射的现象被广泛研究。~(29)S核最外层两个质子处于2s1/2轨道,可能存在这种奇特的行为。先前的实验表明,~(29)S+~(28)Si的总反应截面有着异常大的值。这意味着~(29)S中最后2