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1.
梳理了高校实验室环境-安全-健康准入制度包含的管理内容,从人员管理、设备管理、试剂管理、实验环境管理角度进行了分析。根据现有实验室安全信息化系统运行情况,探讨了将实验室安全信息化系统与实验室信息化系统、设备管理信息化系统进行数据融合和功能优化的要点,重点分析了设备采购及管理系统、实验室安全教育与考试系统、实验室安全检查系统、试剂管理平台、实验室门禁管理系统在功能上的内在关联,从而通过试剂管理平台、实验室门禁控制系统、设备采购系统实现实验室环境-安全-健康准入制度的强制执行。研究发现,高校与环境监测实验室、院系实验室安全管理部门联合促进实验室安全信息化系统、实验室信息化系统、设备管理信息化系统的数据共享与功能升级,可以丰富实验室安全准入制度的内涵和管理手段,加强实验室安全准入制度的强制执行力,提高实验室安全管理效率。  相似文献   
2.
采用过硫酸钠(PDS)直接氧化和催化活化氧化脱色罗丹明B(RhB),分别考察了PDS剂量、pH、催化剂、Cl-浓度对RhB脱色的影响.结果表明,PDS在无外加催化剂下能够有效脱色RhB,pH越低,脱色率越高;当pH 2.4,PDS用量为3.5 g·L-1,在120 min内RhB的脱色率可达92%;自由基淬灭实验表明,酸性条件下主要为PDS直接氧化脱色RhB,并存在小部分硫酸根自由基(SO44·-)作用.在pH 5.6、pH 8.0条件下,外加活性炭纤维(ACF)、四氧化三铁(Fe3O44)、Fe3O44负载型催化剂(ACF/Fe3O44)可促进PDS对RhB脱色;在pH 2.4条件下,外加ACF对RhB脱色的促进作用较小,Fe3O44、ACF/Fe3O44对RhB脱色有一定抑制作用.不同pH和催化剂处理下,低浓度Cl-(0.01、0.04 mO4l·L-1)对RhB脱色速率都呈现抑制作用,高浓度Cl-(0.08 mO4l·L-1)相对于低浓度Cl-处理都呈促进作用.不同浓度Cl-处理在反应前60 min RhB脱色速率差异较大,而反应120 min后脱色率差异较小.提出Cl-通过调控SO44·-脱色RhB途径来影响RhB脱色速率的机理,Cl-竞争消耗SO44·-降低RhB脱色速率,但经一系列反应生成的Cl2·-能与RhB快速反应而提高RhB脱色速率;Cl-对RhB的脱色反应速率的影响存在抑制-促进双重机制,且与Cl-浓度相关.研究结果为基于PDS直接氧化和催化氧化处理含盐染料废水的研究和应用提供了一定的理论依据.  相似文献   
3.
The lack of high-resolution distribution maps for freshwater species across large extents fundamentally challenges biodiversity conservation worldwide. We devised a simple framework to delineate the distributions of freshwater fishes in a high-resolution drainage map based on stacked species distribution models and expert information. We applied this framework to the entire Chinese freshwater fish fauna (>1600 species) to examine high-resolution biodiversity patterns and reveal potential conflicts between freshwater biodiversity and anthropogenic disturbances. The correlations between spatial patterns of biodiversity facets (species richness, endemicity, and phylogenetic diversity) were all significant (r = 0.43–0.98, p < 0.001). Areas with high values of different biodiversity facets overlapped with anthropogenic disturbances. Existing protected areas (PAs), covering 22% of China's territory, protected 25–29% of fish habitats, 16–23% of species, and 30–31% of priority conservation areas. Moreover, 6–21% of the species were completely unprotected. These results suggest the need for extending the network of PAs to ensure the conservation of China's freshwater fishes and the goods and services they provide. Specifically, middle to low reaches of large rivers and their associated lakes from northeast to southwest China hosted the most diverse species assemblages and thus should be the target of future expansions of the network of PAs. More generally, our framework, which can be used to draw high-resolution freshwater biodiversity maps combining species occurrence data and expert knowledge on species distribution, provides an efficient way to design PAs regardless of the ecosystem, taxonomic group, or region considered.  相似文献   
4.
Reductions in global bee populations are threatening the pollination benefits to both the planet and people. Whilst the contribution of bee pollination in promoting sustainable development goals through food security and biodiversity is widely acknowledged, a range of other benefits provided by bees has yet to be fully recognised. We explore the contributions of bees towards achieving the United Nation’s Sustainable Development Goals (SDGs). Our insights suggest that bees potentially contribute towards 15 of the 17 SDGs and a minimum of 30 SDG targets. We identify common themes in which bees play an essential role, and suggest that improved understanding of bee contributions to sustainable development is crucial for ensuring viable bee systems.  相似文献   
5.
Scientists in higher education institutions around the globe recognize the importance of engaging with public stakeholders to share their enthusiasm, explain their science, and encourage primary and secondary students to enter the sciences. However, without direct consideration of students’ and teachers’ perspectives and interests, scientists may design activities around their own goals, limiting the impact on school stakeholders (i.e., students, teachers, paraprofessional staff, students’ parents, and other caregivers). We drew from natural and social science research to describe how expanding the conception of place beyond the biophysical can help engage school stakeholders in meaningful ways. We describe the multidimensional PLACE framework that we developed to integrate perspectives, knowledge, and values of all stakeholders in engagement programming. The framework is organized around topics that stakeholders should discuss early on to ensure successful partnerships. We recommend that scientists identify and use pedagogy that is inclusive; language framed around dialogic communication methods; aims and motivations centered on engagement; cultural funds of knowledge of place (i.e., disciplinary, personal, or experiential knowledge); and evaluation of engagement based on meaningful metrics. Two case studies are presented to illustrate how the PLACE framework components, when addressed, can lead to robust, successful partnerships between scientists and schools.  相似文献   
6.
● B[a]P, nicotine and phenanthrene molecules altered the secondary structure of Aβ42. ● β-content of the peptide was significantly enhanced in the presence of the PAHs. ● Nicotine made stable cluster with Aβ42 peptide via hydrogen bonds. ● Phenanthrene due to its small size, interfered with the Aβ42 monomer more strongly. Recent studies have correlated the chronic impact of ambient environmental pollutants like polycyclic aromatic hydrocarbons (PAHs) with the progression of neurodegenerative disorders, either by using statistical data from various cities, or via tracking biomarkers during in-vivo experiments. Among different neurodegenerative disorders, PAHs are known to cause increased risk for Alzheimer’s disease, related to the development of amyloid beta (Aβ) peptide oligomers. However, the complex molecular interactions between peptide monomers and organic pollutants remains obscured. In this work, we performed an atomistic molecular dynamics study via GROMACS to investigate the structure of Aβ42 peptide monomer in the presence of benzo[a]pyrene, nicotine, and phenanthrene. Interestingly the results revealed strong hydrophobic, and hydrogen-bond based interactions between Aβ peptides and these environmental pollutants that resulted in the formation of stable intermolecular clusters. The strong interactions affected the secondary structure of the Aβ42 peptide in the presence of the organic pollutants, with almost 50 % decrease in the α-helix and 2 %–10 % increase in the β-sheets of the peptide. Overall, the undergoing changes in the secondary structure of the peptide monomer in the presence of the pollutants under the study indicates an enhanced formation of Aβ peptide oligomers, and consequent progression of Alzheimer’s disease.  相似文献   
7.
Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
8.
Heavy metal pollution in soil and wastewater is a worldwide environmental issue in which microorganisms play a significant role for its removal. In the present study, biosorption of Cr(VI) by the live and dead cells of Kocuria sp. ASB107, a radio-resistant bacterium, was investigated. The effect of contact time, solution pH, initial hexavalent chromium concentration and adsorbent dose on biosorption efficiency was studied. Also, live cells were further immobilised on various matrices by different techniques and then were examined for tolerance to chromium biosorption. Experimental results indicated that the removal efficiency of chromium increased with decrease in pH, initial Cr(VI) concentration, and also increase in adsorbent dose and the contact time. The maximum removal efficiency of live and dead cells at acidic pH of 4–4.5, contact time of 24 hours, adsorbent dose 1.6?g/100?mL and initial chromium concentration 25?mg/L were 82.4% and 69.2%, respectively. The adsorption data was described well by Langmuir isotherm model. Among all immobilisation techniques tested, cross-linking showed the highest biosorption of Cr(VI). Results indicated that live cells of Kocuria sp. ASB107 were better than dead ones.  相似文献   
9.
Background: Alcohol use is pervasive among motorists on the road in Ghana; however, we do not know the extent to which this behavior is implicated in road accidents in this country.

Objectives: The main objective of this research was to establish the prevalence of alcohol in the blood of nonfatally injured casualties in the emergency departments (EDs) in northern Ghana.

Method: Participants were injured road traffic crash victims, namely, pedestrians, cyclists, motorcyclists, and drivers seeking treatment at an ED. The study sites were 2 level III trauma centers located in Wa and Bolgatanga. Participants were screened for alcohol followed by breath tests for positive participants using breathalyzers.

Results: Two hundred and sixty-two accident victims visited EDs, 58% of whom were in Wa. Among the victims, 41% were hospitalized and 57% experienced slight injuries. The vast majority (76%) of the casualties were motorcyclists, 13% were pedestrians, 8% were cyclists, and 2% were drivers. Casualties who had detectable alcohol in their blood were predominantly vulnerable road users. In all, 34% of participants had detectable blood alcohol concentrations (BACs) and the mean BAC for all casualties who tested positive and could give definitive BACs was 0.2265 (226 mg/dl). The prevalence of alcohol use was 53% among cyclists, 34% among motorcyclists, 21% among pedestrians, and 17% among drivers. Male casualties were more likely to test positive for alcohol than females. In addition, the prevalence of alcohol was significantly higher among injured casualties in Bolgatanga compared to Wa.

Conclusion: There was a high prevalence of alcohol use among nonfatally injured casualties in northern Ghana and injury severity increased with BAC. AUDIT screening in the hospital, alcohol consumption guideline, road safety education with an emphasis on minimizing or eliminating alcohol consumption, and enhanced enforcement of the BAC limit among motorists are recommended.  相似文献   

10.
佳乐麝香对萝卜种子发芽及DNA损伤的生态毒理影响   总被引:1,自引:0,他引:1  
由于佳乐麝香(HHCB)被广泛应用于日用化工产品中,被持续不断地释放到环境中,所产生的生态风险已引起越来越多的重视。为探究HHCB的生态毒性效应,在水培条件下考察了不同浓度HHCB对萝卜的表观生长指标(发芽率、根伸长抑制率、芽伸长抑制率)和基于随机引物扩增多态性(RAPD)图谱的根尖DNA损伤状况。研究结果显示:低剂量(≤25 mg·L~(-1))胁迫对萝卜发芽无显著影响(P0.05);高剂量(≥50 mg·L~(-1))胁迫可以显著抑制萝卜发芽率(P0.05)。萝卜的根长和芽长抑制率随HHCB浓度增加而呈上升趋势,且根伸长对HHCB胁迫较芽伸长更敏感,更适宜指示HHCB对植物的生态毒性效应。萝卜根尖基因组DNA的RAPD分析结果表明:大于或等于5 mg·L~(-1)的HHCB即可明显导致萝卜根尖基因组DNA损伤,且随着HHCB浓度的升高,根尖基因组DNA含量呈线性降低,DNA多态率增加,基因组模板稳定性(GTS)减小,遗传相似性变远。这表明较低剂量的HHCB胁迫就能够导致萝卜根尖基因组DNA损伤,且随浓度升高而损伤严重。因此,利用RAPD技术获得的萝卜DNA多态性变化可作为检测HHCB遗传毒性效应的敏感生物标记物,为化学品污染生态毒理早期诊断提供科学依据。  相似文献   
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