High-affinity ouabain receptors: primary membrane sensors for ionizing radiation

Although the high sensitivity of the Na/K pump in cell membrane to ionizing radiation is well known in literature, the individual role of different isoforms of pump in determination of its radio-sensitivity is not clear yet. This is the subject of the present investigation. Using isotope, electro-physiological and enzymological methods, the effect of γ-ionizing radiation on cell membrane voltage-current characteristics, acetylcholine-induced membrane current, ²²Na⁺ and ⁴⁵Ca²⁺ exchange between cells and bathing solution, Na+K⁺-ATPase activity, dose-dependent ouabain binding with cell membrane, intracellular cAMP and membrane phosphorylation in snail neurons were studied. The changes in neurons as a result of 30-min γ-radiation exposure of snails to 5.16 Ci/kg at the end of the first 30 min of post-radiation period were as follows: the increase in membrane ionic conductance reversed the ouabain sensitivity of acetylcholine-induced currents, stimulation of ²²Na⁺ and ⁴⁵Ca²⁺ uptakes, inhibition of Na/K pump, activation Na/Ca exchange in reversed mode, increase in ouabain binding with high-affinity α₃ and decrease with α₂ middle-affinity receptors, decrease in intracellular cAMP content and membrane dephosphorylation. On the basis of the obtained data, it is suggested that both α₃ and α₂ catalytic subunits of Na⁺+K⁺-ATPase serve primary membrane sensors through the activation of which the biological effect of γ-radiation on neurons is realized. The IR has activation effects on α₃-dependent Na⁺/Ca²⁺ exchange in forward and its inactivation on α₂-dependent reverse modes.     

Constitutive expression of a high-affinity sulfate transporter in Indian mustard affects metal tolerance and accumulation

The Stylosanthes hamata SHST1 gene encodes a high-affinity sulfate transporter located in the plasma membrane. In this study the S. hamata SHST1 gene was constitutively expressed in Indian mustard [Brassica juncea (L.) Czern.] to investigate its importance for tolerance and accumulation of various oxyanions that may be transported by SHST1 and for cadmium, which is detoxified by sulfur-rich compounds. The transgenic SHST1 lines SHST1-12C and SHST1-4C were compared with wild-type Indian mustard for tolerance and accumulation of arsenate, chromate, tungstate, vanadate, and cadmium. As seedlings the SHST1 plants accumulated significantly more Cd and W, and somewhat more Cr and V. The SHST1 seedlings were less tolerant to Cd, Mo, and V compared to wild-type plants. Mature SHST1 plants were less tolerant than wild-type plants to Cd and Cr. SHST1 plants accumulated significantly more Cd, Cr, and W in their roots than wild-type plants. In their shoots they accumulated significantly more Cr and somewhat more V and W. Shoot Cd accumulation was significantly lower than in wild-type, and As levels were somewhat reduced. Compared to wild-type plants, sulfur accumulation was enhanced in roots of SHST1 plants but not in shoots. Together these results suggest that SHST1 can facilitate uptake of other oxyanions in addition to sulfate and that SHST1 mediates uptake in roots rather than root-to-shoot translocation. Since SHST1 overexpression led to enhanced accumulation of Cr, Cd, V, and W, this approach shows some potential for phytoremediation, especially if it could be combined with the expression of a gene that confers enhanced metal translocation or tolerance.     

Development of sustainable energy systems in Swedish municipalities: A matter of path dependency and power relations

Case studies of two Swedish municipalities indicate that the general energy area was divided into three independent policy areas: one dealing with supply, one with conservation and one with environmental questions related to the Agenda 21 vision of an ecologically sustainable energy system. However, the dominant energy policy area in the municipalities was supply policy. This article discusses why supply policy is dominant and the consequences of this for energy system development. Analysis of this pattern reveals that powerful actors, such as local energy companies, were able to mobilize support for supply policies, not least because they owned the energy plants and distribution networks. These actors were also represented in many different decision arenas; in contrast, actors representing the other energy policy areas often lacked power and resources, and were represented in only a few decision arenas.     

Development of sustainable energy systems in Swedish municipalities: A matter of path dependency and power relations

Abstract

Case studies of two Swedish municipalities indicate that the general energy area was divided into three independent policy areas: one dealing with supply, one with conservation and one with environmental questions related to the Agenda 21 vision of an ecologically sustainable energy system. However, the dominant energy policy area in the municipalities was supply policy. This article discusses why supply policy is dominant and the consequences of this for energy system development. Analysis of this pattern reveals that powerful actors, such as local energy companies, were able to mobilize support for supply policies, not least because they owned the energy plants and distribution networks. These actors were also represented in many different decision arenas; in contrast, actors representing the other energy policy areas often lacked power and resources, and were represented in only a few decision arenas.     

Using social resilience and resource dependency to increase the effectiveness of marine conservation initiatives in Salum,Egypt

The social and economic ramifications of marine conservation strategies such as marine protected areas (MPAs) are important to consider prior to their implementation to ensure that they do not exceed the resilience of resource-users and that resource protection might be maximised through compliance and low resistance. This paper presents a framework in which the human dimensions can be more easily and usefully integrated into the design and delivery of conservation initiatives. The framework espouses quantifying (1) the level of dependency on the resource; (2) perceptions towards conservation initiatives; and (3) social resilience. The framework is applied in Salum, Egypt, which is the site of a prospective MPA.     

旧房,那些岁月年华

住进新房,因还贷压力,我很无奈地卖掉了原来那套旧房。过完了户,说好明天将钥匙交给对方。下午,想起旧房,我忽然坐卧不宁,心里跟猫抓了似的,有湿湿的东西自眼里划过。抓起外套,我奔向旧房。打开旧房门,双眼随着轻慢的脚步,细细抚摸着家里的每一处角落。包暖气的木板斜了,我弯下腰将它扳直,许是用力过猛,手背碰到一处硬角,瞬间出了血,那一刻,也跟着瑟瑟。     

打造网络时代的重庆旅游营销系统

近年来,互联网以一种不可想象的速度向前发展.网络技术的发展和应用使人们在信息共享和交流方面摆脱了时空的局限.旅游业作为21世纪的高成长性行业,它的发展时刻受到信息革命的冲击.针对旅游产品的综合性、无形性、不可转移性和不可贮存性等特点,论述了网络时代旅游业运用网络营销的必然性以及旅游网络营销的优势,并探讨了重庆旅游网络营销的发展策略.     

Virgil, Vigilance, and Voice: Agrifood Ethics in an Age of Globalization

Some 2000 years ago, Virgil wroteThe Georgics, a political tract on Romanagriculture in the form of a poem. Today, as aresult of rising global trade in food andagricultural products, growing economicconcentration, the merging of food andpharmacy, chronic obesity in the midst ofhunger, and new disease and pest vectors, weare in need of a new Georgics that addressesthe two key issues of our time: vigilance andvoice. On the one hand, vigilance must becentral to a new Georgics. Enforceablestandards for food safety, food quality,environmental protection, worker health andsafety, sanitary and phytosanitaryrequirements, animal welfare, and appellationsmust be addressed. On the other hand, a newGeorgics must increase the range of persons whohave voice in the democratic governance of anew global agrifood system. New organizationsand institutions will be needed to accomplishthis task.     

Thomas Malthus,Ester Boserup,and Agricultural Development Models in the Age of Limits

Two competing models have served as the basis for agricultural development policies. One is based on observations and assumptions of The Reverend Thomas Malthus in late eighteenth century Britain, and the other from the Danish economist Ester Boserup in the mid-twentieth century. However, rational agricultural development decisions can only be made using a model that incorporates assumptions based on a technically appropriate model that takes into account the currently status of global systems. A new development model may incorporate elements of both Neo-Malthusian and Boserupian economic-demographic models, but because the world has changed substantially, it can be neither of them alone, nor a hybrid of the two models without significant expansion and refinement. The principles espoused by Malthus and Boserup can thus be used as the starting points in a dialectic argument to arrive at a new agricultural development paradigm.     

The Ethics of Assisted Colonization in the Age of Anthropogenic Climate Change

This paper examines an issue that is becoming increasingly relevant as the pressures of a warming planet, changing climate and changing ecosystems ramp up. The broad context for the paper is the intragenerational, intergenerational, and interspecies equity implications of changing the climate and the value orientations of adapting to such change. In addition, the need to stabilize the planetary climate by urgent mitigation of change factors is a foundational ethical assumption. In order to avoid further animal and plant extinctions, or at the very least, their increased vulnerability to becoming rare and endangered; the systematic assisted colonization of “at risk” species is being seriously considered by scientists and managers of biodiversity. The more practical aspects of assisted colonization have been covered in the conservation biology literature; however, the ethical implications of such actions have not been extensively examined. Our discussion of the value issues, using a novel case study approach, will rectify the limited ethical analysis of the issue of assisted colonization of species in the face of climate change pressures. Beyond sustainability ethics, both animal and environmental ethical approaches will be used and intrinsic versus instrumental value orientations in the literature shall form the basis of our discussion. After the application of all the ethical approaches to the case studies, we conclude that without mitigation and the prospect of a future stable climate, assisted colonization will be involved in an inherently unethical process and a “move and lose it” outcome. With mitigation, there is wide-ranging ethical support for assisted colonization.     

Comparison of Function of Created Wetlands of Two Age Classes in Central Pennsylvania

Hydrogeomorphic (HGM) functional assessment models were used to assess whether function in created wetlands of two ages (1 year old and >12 years old) was equivalent to that of natural (reference) mainstem floodplain wetlands. Reference wetlands scored higher than both created age classes for providing energy dissipation and short-term surface water storage. Reference wetlands scored higher in maintaining native plant community and structure than 1-year-old sites, and 12-year-old wetlands scored higher than reference sites for providing vertebrate habitat structure. Analysis of individual model variables showed that reference wetlands had greater vegetative biomass and higher soil organic matter content than both created wetland age classes. Created wetlands were farther from natural wetlands and had smaller mean forest patch sizes within a 1-km-radius circle around the site than did the reference sites, indicating less hydrologic connectivity. Created wetlands also had less microtopographic variation than reference wetlands. The 1-year-old created sites were placed in landscape settings with greater land use diversity and road density than reference sites. The 12-year-old sites had a higher gradient and a higher percentage of their surrounding area in urban land use. These results show that the created wetlands were significantly structurally different (if not functionally so) from reference wetlands even after 12 years. The most profound differences were in hydrology and the characteristics of the surrounding landscape. More attention needs to be focused on placing created wetlands in appropriate settings to encourage proper hydrodynamics, eliminate habitat fragmentation, and minimize the effects of stressors to the site.     

建设新时代美丽城市的总体思路与战略任务研究

建设美丽中国是党的二十大提出的社会主义现代化强国的重要目标之一。城市是实施新型城镇化、推动绿色发展、建设美丽中国的重要载体,是美丽中国最具代表性的表现形式与具体呈现。面对党的二十大和全国生态环境保护大会整体部署及美丽城市建设现实需求,本文明确建设新时代美丽城市的工作背景及重大意义,评估我国美丽城市建设的进展、成效,分析识别当前新时代美丽城市建设面临的主要问题及挑战,从重点任务、工作机制、政策支撑、带动示范等层面提出开展新时代美丽城市建设的思路与任务建议,为推动建设新时代美丽城市提供支撑。     

高分子材料在环境中的危害及其对策

本文综述了高分子材料在生产过程、使用过程及其废弃物所带来的危害,以及解决危 害的对策。     

秦皇岛市主要环境问题及控制对策

本文以详实的数据阐明了秦皇岛市气、水、声、生态环境质量方面存在的问题。进一步从生产力空间布局、产业结构、能源结构、城市环境基础设施、可持续发展观念五个方面分析了环境问题的成因。最后提出了调整产业结构、加强环境基础设施建设、加大环境综合整治力度、加强生态保护四项措施来解决存在的环境问题,对秦皇岛市的环境发展有一定的指导意义。     

体验经济时代下诸葛八卦村古村落旅游产品的创新设计

在体验经济时代,旅游及其产品被赋予了更深的内涵和更高的期待,而在现实旅游开发中却存在很大的不足.在旅游与体验的内在关系分析基础上,根据发生学的序曲、发展、高潮和结尾四部曲方法,结合诸葛八卦村的旅游资源特色,创新设计了诸葛八卦村古村落旅游的行程和活动安排,进行了深度体验型的古村落旅游产品的开发.     

畜禽废水处理技术及其应用进展

针对我国养殖业废水污染日益严重的现状,介绍了畜禽废水还田利用、自然处理以及工业化处理的优缺点、国内外应用现状以及研究的重点,并结合我国的实际情况,提出现阶段我国养殖业废水应重点发展还田利用技术与自然处理技术,并及时建立畜禽废水处理设计数据库以及编写设计规范。