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91.
本文介绍了如何适应新形势下的国际国内环境,转变原有的发展模式,提高工业企业产品质量水平,增强竞争力。  相似文献   
92.
This paper asks how the livability of socially disadvantaged urban neighborhoods can be improved with the help of publicly funded area-based urban regeneration. It builds on the history of area-based regeneration policies in Germany aiming at upgrading and resolving urban problems at the neighborhood level. Its main argument is as follows. First, the fate of conventional physical upgrading policies focusing on the livability of deprived urban areas depends on the development environment. While successful upgrading sometimes makes inner-city neighborhoods so attractive that they run into a trend towards gentrification and displacement of the urban poor, the stabilization of less privileged areas cannot always be guaranteed. Second, alternative approaches are needed, linking limited physical upgrading with socially oriented policies, building on strategies like neighborhood management and empowerment. Third, they can make a substantial contribution to stabilizing deprived neighborhoods, thereby improving the general living conditions and the opportunities of the urban poor. However, they require at least some permanent intervention. Thus, they transcend the logic of area-based regeneration normally limited to restoring faith into the private real estate market and thereby directing inward investment into them that improves the quality of the physical environment. Fourth, they are hardly able to overcome significant negative stigmatization in cities that are severely hit by economic downturn and population decline. This is especially true when they act as arrival areas for consecutive waves of migrants, making it necessary to redefine the role of those areas in cities and accepting their high concentration of urban problems as a starting point for different area-based policies dealing with them. The key empirical background of the paper is the German system of urban development grants and an evaluation of the so-called program of “socially integrative city”.  相似文献   
93.
Glial cells are crucial for maintaining central nervous system (CNS) homeostasis. They actively participate in immune responses, as well as form functional barriers, such as blood-brain barrier (BBB), which restrict the entry of pathogens and inflammatory mediators into the CNS. In general, viral infections during the gestational period can alter the embryonic and fetal environment, and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life, as highlighted by our group for Zika virus infection. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) induces a cytokine storm and, during pregnancy, may be related to a more severe form of the coronavirus disease-19 (COVID-19) and also to higher preterm birth rates. SARS-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells, which can compromise neuronal plasticity and synaptic function. However, the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS, including brain development during childhood and adulthood, remains undetermined. Our group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders, which are strongly related to the inflammatory response. Thus, based on these relationships, we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life, focusing on the potential role of glial cells. Thus, it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy.  相似文献   
94.
JONG HWAN SUNG 《Biocell》2022,46(5):1177-1180
Organ-on-a-chip technology aims to reproduce the key physiological features of human organs and tissues, even complex actions of multi-organ interaction. While organ-on-a-chips at single-organ level has made notable achievement during the last decade, multi-organ-on-a-chips, which manifests unique advantages, has started gathering attention only recently. In this viewpoint, we discuss the current status of organ-on-a-chip technology, with a specific emphasis on multi-organ-on-a-chip. Key technological advances contributing to the maturation of the field, and challenges that need to be addressed before wider adoption in relevant fields are discussed. We will share our perspectives on how the multi-organ-on-a-chip can improve the drug development process.  相似文献   
95.
The biology and physiology of Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), also known as the ham, cheese or mold mite, is reviewed along with methods that have been evaluated for managing and controlling this pest. This review was conducted because the ham mite is an important target pest of the dry cured ham industry. Methyl bromide has been historically used to control mite infestations, but is now banned or being phased out of use in most countries because it is an ozone-depleting substance. Only commercially available stockpiles and quarantine and pre-shipment methyl bromide are available for use in countries that require such action. This review compares the effectiveness and feasibility of recently investigated methods to control mite infestations on dry cured ham and to discuss integrated pest management plans for ham mites. The review also proposes methods for conducting a prevention and monitoring-based integrated pest management program that relies on definitive mitigation such as fumigation only when mite numbers exceed a critical action threshold.  相似文献   
96.
改革开放40年来,我国经济飞速发展的同时也产生了一系列的生态环境问题,土壤重金属污染问题尤为严重。上世纪80年代,江西贵溪地区数家大中型冶炼、化工类企业在九牛岗区域逐渐集中,由于长期对资源的粗放型开发,高耗能、高污染、高排放加之低效率生产对贵溪J区域农田造成了严重污染,土壤重金属含量严重超标,生态环境遭到破坏。污染治理过程中,各相关主体从“各自为政”到“共同发力”,从长期得不到有效解决到多主体相互协作综合治理取得成效,走出了一条政府主导,企业主体,村民参与,社会支持的土壤重金属污染治理新路。本文着重就自然资源、环境保护与社会经济如何协调发展,探索运用多中心治理理论对土壤污染治理进行实践,推动经济发展与生态环境和谐共进。  相似文献   
97.
As cities grow, both the productivity of their inhabitants and the income distribution among them is expected to change. While the empirical literature has widely shown how productivity (and income) changes with city size, the empirical evidence on the effects on income inequality remains very limited. The few papers that study the relationship between city size and city-level inequality focus on a single country and do not provide international comparative evidence. In this paper, we study the relationship between city size and income inequality at city level for a sample of 153 functional urban areas (FUAs) across 11 OECD countries.  相似文献   
98.
Abstract

Once celebrated as a tourist destination, and now filled with derelict hotels, Varosha is a contested landscape at once embodying contradicting political and economic aspirations and featuring vividly in negotiations for political reconciliation in Cyprus. This paper provides a history of the antagonisms that surround this area by interrogating the creation of hotels and landscapes of leisure in 1960s Varosha and by exposing how these aspired to transform the cultural identity of the entire island. Casting the spotlight on the Golden Sands hotel, the paper demonstrates that, along with advancing iconographies of global modernity, hotel design was insidiously shaped by ethnic disputes as well as socio-economic and environmental contestations. Seen in the context of other conflict-torn cities, this history of the contested landscape of Varosha provides crucial insights into the imbrications of architectural history and design practices in the management of contested instances of modern, twentieth-century heritage.  相似文献   
99.
王琪 《陕西煤炭》2020,39(1):96-98,141
煤炭在促进经济的同时也给生态环境带来了严重的影响,采取有效措施减少煤炭产业对环境的污染,具有很重要的现实意义。为改善环境污染问题,分析了煤炭产业的环境保护问题并提出相应的解决措施。分析认为,需在国家、地方政府、企业层面强化生态环境保护;从提升资源配置、促进煤炭产业转型升级、加强创新驱动等方面促进资源合理开发;需通过制度保障提升科研协作的成效,促进煤炭绿色开采及清洁利用。在注重环保的同时,落实环境一体化产业政策,向环境依存度较低、知识密集型方向发展,可促进行业可持续发展。  相似文献   
100.
In this article, we study shale gas pad development under natural gas price uncertainty. We optimize the sequence of operations, gas curtailment, and storage on a single pad to maximize the net present value. The optimization problem is formulated as an mixed-integer linear programming model, which is similar to the one proposed by Ondeck et al. We investigate how natural gas price uncertainty affects the operation strategy in the pad development. Both two-stage and multistage stochastic programming are used as the mathematical framework to hedge against uncertainty. Our case study shows that there is value of using stochastic programming when the price variance is high. However, when the variance of the price is low, solving the stochastic programming problems does not create additional value compared with solving the deterministic problem.  相似文献   
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