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81.
82.
Project‐based construction workers in the Australian construction industry work long and irregular hours and experience higher levels of work‐to‐family conflict and burnout than office‐based workers, giving rise to an interest in alternative work schedules as a means of supporting work–life balance. Alternative work schedules were implemented in four case study construction projects in Australia. Interventions differed between projects, with two implementing a compressed work week, and the others introducing reduced hours schedules (one of which was optional). Data were collected from each case study project, using various combinations of focus groups, surveys, interviews and daily diary collection methods. The results were mixed. The compressed work week appears to have been favourably received where it was introduced. However, waged workers still expressed concerns about the impact on their weekly ‘take‐home’ pay. Attempts to reduce work hours by changing from a six‐ to a five‐day schedule (without extending the length of the working day between Monday and Friday) were less favourably received. Waged workers, in particular, did not favour reduced hours schedules. The results confirm the existence of two distinct labour markets operating in the Australian construction industry and markedly different responses to alternative work schedules, based upon whether workers are waged or salaried. The results clearly show that attempts to improve work–life balance must take the structural characteristics of the industry's labour markets into consideration in the design of interventions. The impact of alternative work schedules is likely to be moderated by institutional working time regimes within the construction industry.  相似文献   
83.
Natural ventilation is a proven strategy for maintaining thermal comfort in non-domestic buildings in the UK. The energy consumption and thus the carbon dioxide emissions that contribute to global warming are lower than in conventional air-conditioned buildings. However, the ambient temperatures in the UK have risen over the last decade and new climatic data for use in the design of naturally ventilated buildings has been published. Using these data and dynamic thermal modelling, it is shown that passive stack ventilation alone was unlikely to maintain summertime comfort in a proposed University College London building within an urban heat island. The stack ventilation strategy was evolved by the introduction of passive downdraught cooling. This low-energy technique enables cooled air to be distributed throughout the building without mechanical assistance. The underlying principles of the technique were explored using physical models and the anticipated performance predicted using thermal modelling. The architectural integration is illustrated and the control strategy described. The resulting building is believed to be the first large-scale application of the passive downdraught cooling technique; construction began in late 2003.  相似文献   
84.
《Urban Water Journal》2013,10(5):392-404
Today's modern cities' ‘big-pipes in, big-pipes out’ potable water supply approach does not offer society the resilience for adaptation to future climate challenges. One approach towards building resilience would involve cities adopting diverse, alternative water supplies; such as recycled wastewater, greywater and stormwater, within a fit-for-purpose philosophy, incorporating a mix of centralised and decentralised technologies. Globally, modern cities have limited on-ground experience with such complex approaches, despite ad-hoc policy rhetoric to the contrary and multiple technological options. Through considering the implicit and technocratic hydrosocial contract underpinning the current ‘big pipes’ approach, it appears the judgement and advice of ‘water experts’ is a significant determinant regarding opportunities for realising more resilient water supplies. Contrasting primary and secondary survey data from water experts and communities across Australian cities in relation to their receptivity to alternative water supplies; it is evident that community members are far more receptive than water experts expect. Thus, this difference in perception is potentially a significant barrier to realising a resilient approach. Path-dependant decision-making and practice is pervasive throughout the urban water field, and while the physical artefact of the traditional water supply system remains largely invisible and disconnected from communities, it is the implicit hydrosocial contract that keeps water experts disconnected from communities. Based on evidence presented in this paper, shifting the current hydrosocial contract to a more resilient approach is vulnerable to business as usual. Recommendations are offered for fundamentally reshaping this contract through deliberative processes that work towards enabling co-governance, co-design and co-management of this alternative and complex water supply approach into the future.  相似文献   
85.
为了优化替代眼刺激动物试验的牛角膜浑浊和渗透性(BCOP)实验的方法,提高其适用范围和预测性,选取新鲜牛眼角膜,直接暴露液体化学受试物作用10 min,后孵育2 h并用荧光素钠处理90 min,采用浊度仪检测角膜浑浊度,用酶标仪检测荧光素钠渗透性,同时将角膜常规固定和制备组织学切片,观察组织学病理变化并评分,基于上述3个指标建立预测模型。结果显示,将角膜浑浊度和渗透性2个定量指标,与角膜上皮组织、基质组织和内皮细胞的组织学变化评分进行组合,可对轻微刺激到中等刺激的范围进行准确细分。研究表明,结合组织学观察的优化BCOP方法可提高其预测性,适用于眼刺激机制研究和化妆品评估。  相似文献   
86.
综述了在21世纪毒性测试愿景与策略倡议下,以及现代科技发展和法规监管体系变革的背景下,有害结局通路(AOP)的提出和发展。重点介绍了AOP的概念和指南,AOP的基本组成、构建条件和信息共享,AOP的网络和评估;讨论了AOP在皮肤致敏和鱼类早期发育2个毒性终点的开发和应用情况,及其作为自上而下和从中间开始的2种AOP开发策略的实例;最后提出了AOP以现代科技发展为动力、毒性预测现代化为基础、推动法规监管模式变革为目标的发展策略。AOP指南也为替代动物测试方法的开发和检测技术创新提供了难得的机遇。  相似文献   
87.
Clinically significant antibiotic resistance is one of the greatest challenges of the twenty‐first century. However, new antibacterial agents are currently being developed at a much slower pace than our growing need for such drugs. Given their diverse biological activities and clinical applications, many bioactive heterocyclic compounds containing a benzimidazole nucleus have been the focus of interest for many researchers. The benzimidazole nucleus is a structural isostere of naturally occurring nucleotides. This advantage allows benzimidazoles to readily interact with the various biopolymers found in living systems. In view of this situation, much attention has been given to the exploration of benzimidazole‐based antibacterial agents, leading to the discovery of many new chemical entities with intriguing profiles. In this minireview we summarize novel benzimidazole derivatives active against various bacterial strains. In particular, we outline the relationship between the structures of variously modified benzimidazoles and their antibacterial activity.  相似文献   
88.
Capuramycins are one of several known classes of natural products that contain an l ‐Lys‐derived l ‐α‐amino‐?‐caprolactam (l ‐ACL) unit. The α‐amino group of l ‐ACL in a capuramycin is linked to an unsaturated hexuronic acid component through an amide bond that was previously shown to originate by an ATP‐independent enzymatic route. With the aid of a combined in vivo and in vitro approach, a predicted tridomain nonribosomal peptide synthetase CapU is functionally characterized here as the ATP‐dependent amide‐bond‐forming catalyst responsible for the biosynthesis of the remaining amide bond present in l ‐ACL. The results are consistent with the adenylation domain of CapU as the essential catalytic component for l ‐Lys activation and thioesterification of the adjacent thiolation domain. However, in contrast to expectations, lactamization does not require any additional domains or proteins and is likely a nonenzymatic event. The results set the stage for examining whether a similar NRPS‐mediated mechanism is employed in the biosynthesis of other l ‐ACL‐containing natural products and, just as intriguingly, how spontaneous lactamization is avoided in the numerous NRPS‐derived peptides that contain an unmodified l ‐Lys residue.  相似文献   
89.
In this present study, the compression ignition engine was designed to run on CIME (Calophyllum inophyllum methyl ester) biodiesel with nanoparticles. The TiO2 nanoparticle is added to the biodiesel in the form of nanofluid at concentration levels of 100?ppm whereas ethanox is added at levels of 100, 200 and 500?ppm. The nanoparticle and the ethanox are dispersed by the ultrasonication process. The addition of nanofluid reduces the particulate emission like nitrogen oxide (NOx) at 100% load. The efficiency is better and emission is reduced owing to the influence of explosion of water molecules present in the biodiesel. We found ethanox to be a superlative nanofluid to reduce the emission of toxic gas at appreciable levels. We have witnessed a 20% reduction in emission of NOx and 10% reduction of other particulate emission. In addition, the exit geometry of exhaust is modified from a circular shape to an elliptical one and the consequence of the geometry is calculated.  相似文献   
90.
噪音污染业已成为除“三废”之外的第四类污染。噪音如同其他的污染一样,对人类的生产、生活有巨大的危害性。本文指出了我国噪音污染的现状,分析了我国噪音污染防治立法存在的一些问题,并在借鉴国外立法经验的基础上,提出了完善我国噪音污染防治立法的建议。  相似文献   
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