Effect of Pyrethrins and Rosemary on the ATPase Activities of Rat Cerebral Synaptosome

除虫菊酯越来越广泛地被应用于农业和家庭昆虫防治,主要通过作用于膜结合蛋白而对动物起神经毒性.迷迭香因其抗氧化功能而被应用于很多商业化的除虫菊酯产品中.本实验以大鼠大脑突触体ATP酶为研究对象,对除虫菊酯和迷迭香的药理学进行了研究.用Percoll梯度离心法分离突触体,通过检测无机磷的量来测定总ATP酶和Mg2+-ATP酶活性.结果表明,除虫菊酯在浓度为10 μmol/L时总ATP酶和Mg2+-ATP酶分别降低到对照的80.3%和46.9%.迷迭香在浓度为0.3～30 μmol/L时几乎不影响ATP酶活性,当浓度上升到3 000 μmol/L时,总ATP酶活性降低到66.8%,而Mg2+-ATP酶活性降低到54.5%. 10 μmol/L 除虫菊酯和30 μmol/L迷迭香混合物引起总ATP酶和Mg2+-ATP酶分别降低到72.9%和33.4%.结论: 1) 除虫菊酯能抑制大鼠大脑ATP酶活性; 2) 迷迭香只在高浓度下才对ATP酶有抑制作用; 3) 迷迭香能增强除虫菊酯对ATP酶的抑制作用.图3参19

Human activities and interests within and around lakes of the Victoria and Kyoga basin and their consequences to sustainable fish production

Of all the great lakes, Lake Victoria has the highest population concentration on its fringes. This has resulted into serious human impacts on the ecosystem through intense agricultural activities (cultivation, livestock and over fishing), sporadic settlements, urbanization and industrial establishments. The consequences have been loss of animals and plant life, deforestation and general land degradation, pollution, loss of water quality and clean air. Aquatic life has become endangered and less guaranteeing to continued fish production. Awareness workshops and general talks have been done to a few selected communities by the lakes landing sites and in the catchment area to mitigate the deteriorating environmental conditions. Naturally the situation calls for reversal to the increasing stress of the ecosystem. As a result, every water body surveyed put forward some mitigation suggestions

Effect of microbial activities on the mobility of copper in stabilised contaminated soil

Stabilisation, using a wide range of binders including wastes, is most effective for heavy metal soil contamination. Bioremediation techniques, including bioaugmentation to enhance soil microbial population, are most effective for organic contaminants in the soil. For mixed contaminant scenarios a combination of these two techniques is currently being investigated. An essential issue in this combined remediation system is the effect of microbial processes on the leachability of the heavy metals. This paper considers the use of zeolite and compost as binder additives combined with bioaugmentation treatments and their effect on copper leachability in a model contaminated soil. Different leaching test conditions are considered including both NRA and TCLP batch leaching tests as well as flow-through column tests. Two flow rates are applied in the flow-through tests and the two leaching tests are compared. Recommendations are given as to the effectiveness of this combined remediation technique in the immobilisation of copper. © 2005 Taylor & Francis Group.

In vitro activities of small peptides from snake venom against clinical isolates of drug-resistant Mycobacterium tuberculosis

The recent re-emergence of tuberculosis, especially the multidrug-resistant cases, has highlighted the importance of screening effective novel drugs against Mycobacterium tuberculosis. In this study, the in vitro activities of small peptides isolated from snake venom were investigated against multidrug-resistant M. tuberculosis. Minimum inhibitory concentrations (MICs) were determined by the Bactec TB-460 radiometric method. A small peptide with the amino acid sequence ECYRKSDIVTCEPWQKFCYREVTFFPNHPVYLSGCASECTETNSKWCCTTDKCNRARGG (designated as vgf-1) from Naja atra (isolated from Yunnan province of China) venom had in vitro activity against clinically isolated multidrug-resistant strains of M. tuberculosis. The MIC was 8.5 mg/l. The antimycobacterial domain of this 60aa peptide is under investigation. (C) 2003 Elsevier Science B.V. and the International Society of Chemotherapy. All rights reserved.

Rhinopithecus bieti at Tacheng, Yunnan: Diet and daytime activities

We collected data on diet and activity budget in a group of Rhinopithecus bieti at Tacheng (99degrees 18'E, 27degrees 36' N, between 2,700 - 3,700 m asl), Yunnan, from March 1999 to December 2000. We mainly recorded species-parts eaten with feeding scores from scanning state behaviors of one-male units in tree-crowns. We also conducted microscopic analysis of feces collected monthly. The subjects consumed 59 plant species, belonging to 42 genera in 28 families, of which 90 species-parts were distributed as follows: 21 in Winter, 38 in spring, 39 in Summer, 47 in autumn. Conversely, the group annually spent, on average, 35% of daytime feeding, 33% resting, 15% moving, and 13% in social activities. Seasonal changes are apparent in daytime budget and food item-related feeding time in tree-crowns, food remains in feces, and the number of species-parts eaten. Correlations within and between food items and time budget clearly indicate maximization of foraging effectiveness and minimization of energy expenditure. In consideration of reports from northern and southern groups, that which underlay the specific adaptation to the habitat appeared to be similar to those of other colobines. Thus, the ultimate factors for survival of the species are more hopeful than expected.

Purification, characterization and biological activities of the L-amino acid oxidase from Bungarus fasciatus snake venom

L-Amino acid oxidases (LAAOs) are widely distributed in snake venoms, which contribute to the toxicity of venoms. However, LAAO from Bungarus fasciatus (B. fasciatus) snake venom has not been isolated previously. In the present study, LAAO from B. fasciat

Exploring key sustainable development themes through learning activities

The Masters programme in Engineering for Sustainable Development at Cambridge University explores a number of key themes, including dealing with: complexity, uncertainty, change, other disciplines, people, environmental limits, whole life costs, and trade-offs. This paper examines how these concepts are introduced and analyses the range of exercises and assignments which are designed to encourage students to test their own assumptions and abilities to develop competencies in these areas. Student performance against these tasks is discussed and student feedback is also presented, with a focus on how their awareness of the themes are met through a range of activities.

Exploring key sustainable development themes through learning activities

Purpose: The paper examines how a number of key themes are introduced in the Masters programme in Engineering for Sustainable Development at Cambridge University through student centred activities. These themes include dealing with complexity, uncertainty, change, other disciplines, people, environmental limits, whole life costs, and trade-offs. Design/methodology/approach: The range of exercises and assignments designed to encourage students to test their own assumptions and abilities to develop competencies in these areas are analysed by mapping the key themes onto the formal activities which all students undertake throughout the core MPhil programme. The paper reviews the range of these activities that are designed to help support the formal delivery of the taught programme. These include residential field courses, role plays, change challenges, games, systems thinking, multi criteria decision making, awareness of literature from other disciplines and consultancy projects. An axial coding approach to the analysis of routine feedback questionnaires drawn from recent years has been used to identify how student’s own awareness develops. Also results of two surveys are presented which tests the students’ perceptions about whether or not the course is providing learning environments to develop awareness and skills in these areas. Findings: Students generally perform well against these tasks with a significant feature being the mutual support they give to each other in their learning. The paper concludes that for students from an engineering background it is an holistic approach to delivering a new way of thinking through a combination of lectures, class activities, assignments, interactions between class members, and access to material elsewhere in the University that enables participants to develop their skills in each of the key themes. Originality /value: The paper provides a reflection on different pedagogical approaches to exploring key sustainable themes and reports students own perceptions of the value of these kinds of activities. Experiences are shared of running a range of diverse learning activities within a professional practice Masters programme.