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291.
Laura Braida Sergio Crovella Michele Boniotto Ariella Luchesi Umberto de Vonderweid Bruno Casetta Antonio Amoroso 《黑龙江环境通报》2001,21(7):543-546
We describe a quantitative, rapid, sensitive and reproducible tandem mass spectrometry (MSMS) method for the one-step detection of aminoacid (AAs) and acylcarnitine (ACs) concentrations in amniotic fluid. This technology is quicker and more sensitive than other methods used to date since it is possible to determine very low AA and AC concentrations in samples simultaneously in a single run. The high degree of automation allows a large number of pregnancies to be screened for metabolic defects in a very short time. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
292.
Alain?DejeanEmail author James?M.?Carpenter Bruno?Corbara Pamela?Wright Olivier?Roux Louis?M.?LaPierre 《Die Naturwissenschaften》2012,99(4):265-273
Here we show that trying to rob prey (cleptobiosis) from a highly specialized predatory ant species is risky. To capture prey,
Allomerus decemarticulatus workers build gallery-shaped traps on the stems of their associated myrmecophyte, Hirtella physophora. We wondered whether the frequent presence of immobilized prey on the trap attracted flying cleptoparasites. Nine social
wasp species nest in the H. physophora foliage; of the six species studied, only Angiopolybia pallens rob prey from Allomerus colonies. For those H. physophora not sheltering wasps, we noted cleptobiosis by stingless bees (Trigona), social wasps (A. pallens and five Agelaia species), assassin bugs (Reduviidae), and flies. A relationship between the size of the robbers and their rate of capture
by ambushing Allomerus workers was established for social wasps; small wasps were easily captured, while the largest never were. Reduviids, which
are slow to extract their rostrum from prey, were always captured, while Trigona and flies often escaped. The balance sheet for the ants was positive vis-à-vis the reduviids and four out of the six social
wasp species. For the latter, wasps began by cutting up parts of the prey’s abdomen and were captured (or abandoned the prey)
before the entire abdomen was retrieved so that the total weight of the captured wasps exceeded that of the prey abdomens.
For A. pallens, we show that the number of individuals captured during attempts at cleptobiosis increases with the size of the Allomerus’ prey. 相似文献
293.
采用模型模拟水稻热害过程及其可能的产量损失是水稻耐高温研究的重要一环,但较精确地测定水稻冠层的微气象条件还存在诸多困难。采用最新研制的水稻冠层微气象测定仪Mincer实地测定法研究了水稻花期热害受害下的冠层微气象特征,并将相关数据与邻近国家基本气象观测站的数据比较,从而形成了水稻冠层、水稻田田面上部(距田面2倍株高,约1.9m)和空旷地(距地面1.5m)等的对比。结果表明,供试品种受到花期热害后,结实率降低4.0%,达到显著受害水平。在此条件下,日平均气温值由水稻田冠层、水稻田上部与空旷地相比依次升高,水稻冠层与水稻田上部的温度值一般分别比空旷地低2.05、0.92℃,且在连续高温的部分时段出现冠层温度的异常升高;相对湿度值反之,由冠层内部、水稻田上部与空旷地依次降低,水稻冠层与水稻田上部的相对湿度值分别比空旷地低高14.55%、5.97%(绝对值)。此外,高温天气下开花前后水稻田上部与冠层温湿度差的变化幅度都小于常温天气,且出现的时间段早于常温。这些结果,对设定水稻高温受害鉴定条件、模拟水稻高温受害过程均具有重要指导意义。 相似文献
294.
295.
Bruno Takahashi Guy Edwards J. Timmons Roberts Ran Duan 《Environmental Communication: A Journal of Nature and Culture》2015,9(2):228-247
The engagement of environmental non-governmental groups in collaborative communication efforts and decision-making about climate change remains a significant challenge. In Latin America, the website Intercambio Climático was set up to attempt to play a breakthrough role in the region's discussion of climate change. This case study focuses on the development, accomplishments, and challenges of this unique online communication initiative among non-governmental organizations working in climate change issues in Latin America with a US-based partner, as a vehicle to achieve their goals. We used secondary data and in-depth interviews to examine this platform's role in disseminating information and influencing decision-making. The results suggest that generally the participants perceive the website positively, but there are also problematic aspects of the collaboration that are not fully recognized by the members, which prevents a more functional and effective communication strategy. 相似文献
296.
297.
298.
Sustainable mangrove management needs to consider trade-offs between multiple benefits provided by mangrove ecosystems and to balance the conflicting objectives of various stakeholders. The aim of the present study is to assess the sustainability of mangrove management based on the life cycle approach. We examine two mangrove management systems in Thailand, namely, the strict preservation and charcoal production systems. The results show that the strict preservation system has an advantage over the charcoal production system from the environmental perspective (the net amount of CO2 absorbed by mangroves) while the charcoal production is a more favorable system than strict preservation from the social perspective (the amount of employment created in local communities). On the other hand, it is difficult to say that both systems are sustainable from an economic aspect. The charcoal production system needs to develop improved management regimes for commercial charcoal production and requires financial assistance in the period when its net cash flows are negative. As solutions for these problems, the introduction of community forest management and the utilization of a fund for REDD (Reducing Emissions from Deforestation and Degradation in Developing Countries) can be proposed. 相似文献
299.
This paper presents an economic evaluation of three typical recycling processes for the five main types of waste electronic home appliances (EHA) (TV set, refrigerator, washing machine, air conditioner and personal computer) in Beijing, the capital of China. The main purpose is to identify the formal management framework with economic feasibility for the waste EHA generated in large municipalities of China. It is found that the advanced technologies, which have mechanical processing units, should be introduced to recover more valuable materials from the waste appliances. Net revenues with a range of 90–240 RMB (Chinese currency unit, 1.0 USD ≈ 8.0 RMB) per unit, depend on the type of appliance, could be expected in case of using the most complicated procedures which can separate both metals and plastics from the shredded mixtures. However, the recycling of waste refrigerator and waste washing machine will, respectively, spend about 100 and 6 RMB per unit if solely by simple manual dismantling. Revenues from recycling of the other three types of appliances are positive but quite low in this case. Although positive revenues could be achieved from the isolated evaluation of recycling, the entire management system, which also covers the phases of collection and transportation, is economically infeasible if the waste appliances are bought from the households still at current prices. Based on a survey of the householder's attitude to the cost for waste EHA management, which was conducted earlier, the practical way to construct a formal management system for waste EHA in Beijing is to reduce the citizen's traditional expectation to the values of waste appliances and encourage their transfer to the formal collection system at lower prices. 相似文献