Gamergates in the myrmicine genus <Emphasis Type="Italic">Metapone</Emphasis> (Hymenoptera:Formicidae)

Gamergates (i.e. mated reproductive workers) are mostly known from ant species within the Ponerinae. We report here the discovery of gamergates in two species of the subfamily Myrmicinae. Until now, mated reproductive females in colonies of myrmicine species have been considered morphologically distinct from the worker caste. However, in two species of the myrmicine Metapone (Metapone madagascarica and a newly discovered, not yet described Metapone species) all workers have six ovarioles and a spermatheca; and some of them are mated. There are no morphological differences between mated and non-mated workers. Field observations and laboratory studies indicate that colonies of the Metapone species can reproduce with gamergates only.     

Influence of conservation tillage on winter bird use of arable fields in Hungary

Bird use of conservation tillage-established (CT—seedbed preparation without soil inversion) crops was assessed at two adjacent sites in western Hungary, in comparison with conventionally established (mouldboard ploughed—P) fields. Bird abundance was assessed in a typical rotation of spring-sown maize and winter wheat in three consecutive winters. In the first winter, several species and the guild of seed-eating passerines were significantly more abundant on CT established plots, in both crop types. In the second winter, only starlings were more abundant on CT plots. In the third winter, only skylarks favoured CT over P plots. In combination with agri-environment scheme measures designed to provide resources for biodiversity, conservation tillage could play a role in softening the impact of agriculture on farmland birds in Hungary and elsewhere in Eastern Europe, in addition to its potential for reducing soil erosion and diffuse pollution.     

含硫污水系统耐蚀材料的筛选与应用

针对西北地区一综合炼油厂含硫污水管线的严重腐蚀问题，分析了腐蚀原因，确立了材料筛选方案，通过实验室静态挂片试验绘制了重量损失率变化曲线和现场挂片等试验手段，筛选推荐出了树脂玻璃钢耐蚀材料。工业生产应用结果表明，MFE-2型树脂玻璃钢是适用于该厂含硫污水系统的耐蚀材料，为类似装置的长周期运行提供了借鉴和经验。     

抓源头治理是落实“两控区”2000年初期目标的优先选择

针对我国煤中硫分赋存状况,抓源头治理,分别对高硫煤,中硫煤和低硫煤采取不同对策,切实有效地实现“两控区”２０００年的初期目标。     

Cardiac Contractility: How Calcium Activates the Myofilaments

2+   concentrations tropomyosin is located at the edge of the thin filament, thereby interfering with the formation of strong actin-myosin linkages (blocked state). An increase in Ca²⁺ activity causes an azimuthal shift of tropomyosin around the filament (by about 30°), thereby increasing the probability of low-force crossbridge interaction, a process which by cooperative effects induces further tropomyosin movement (by an additional 10°) which results in the open state of the filament characterized by forceful crossbridge interaction. (This mechanism may be analogous to that in ligand-gated ion channels, where ligand binding increases the open probability of the pore.) The extent of activation then depends on the free Ca²⁺ concentration and on the calcium sensitivity of the thin filament that may be affected by protein phosphorylation, crossbridge attachment, the troponin isoform composition of the filament, and novel calcium-sensitizing drugs that act on the contractile or regulatory proteins and thus increase the force of the heart.     

Carbon Budget Implications of the Transition from Natural to Managed Disturbance Regimes in Forest Landscapes

Land-use change from an unmanaged to a managed forested landscape in northern forests is associated with a reduction of the area annually affected by natural disturbances (wildfires and forest insects) and the introduction of harvesting as a new disturbance. This study examined the impacts of changes in the disturbance regime-the frequency and type of disturbance-on landscape-level carbon (C) content and fluxes. The Carbon Budget Model of the Canadian Forest Sector was used to assess these impacts in six representative landscapes (100,000 ha each) with a range of disturbance regimes that are characteristic of conditions in coastal British Columbia, the interior of British Columbia, and the eastern boreal forest in Canada. The model was used to simulate ecosystem C fluxes during a period of natural disturbances, a 50-year transition period during which harvesting replaced natural disturbances, followed by 150 years of harvesting. The initial landscape-level biomass C content under natural disturbance regimes in the six example landscapes was 22 to 75% of their potential maximum content which is often used as the reference or baseline case. After 200 years of forest management, the C stored in the landscape plus the C retained in forest products manufactured from harvested biomass was between 58 and 101% of the landscape C content prior to the onset of harvesting. Landscape-level ecosystem C content was found to be affected by changes in the disturbance frequency, the age-dependence of the disturbance probabilities, and the disturbance-specific impacts on ecosystem C content. The results indicate that using the potential maximum C content of a landscape as the baseline always overestimates the actual C release due to land use change. A more meaningful procedure would be to assess the actual differences in landscape-level C content between the natural and the managed disturbance regime.     

微电解法处理印染废水的研究

本文对微电解法处理印染废水进行了试验研究．对含有直接、活性和硫化染料的印染废水，ＣＯＤ去除率可达７０％以上，脱色率可达９０％以上．得出了电压、停留时间与处理效率和能耗之间的关系．试验说明，微电解法处理印染废水是一种高效、低耗、经济可行的方法．     

重金属在牡蛎(Crassostrea virginica)中的生物积累及其影响因素的研究

牡蛎软体，贝壳和沉积物中Ｃｄ、Ｃｒ、Ｃｕ、Ｆｅ、Ｍｎ、Ｐｂ和Ｚｎ等重金属元素被同步分析研究，研究结果表明，重金属在牡蛎中的生物积累是牡自身的新陈代谢、重金属元素的地球化学性质和环境诸因素综合影响的结果，其中牡蛎斩生理作用对重金属在软体中的积累产生的影响尤为重要，而贝壳中重金属的积累对来自环境的影响更为敏感。