Monitoring pollution in Tunisian coasts using a scale of classification based on biochemical markers in worms Nereis (Hediste) diversicolor

This paper aims to assess the marine environment quality along the Tunisian coasts using a statistical approach based on biomarkers response in the polychaete worms Nereis (Hediste) diversicolor. Worms were collected from six sites: Bizerta Lagoon, Gargour, Nakta, Mahres, Skhira and from Teboulba considered as a reference site. The biomarkers selected in this work were (1) the activities of cytochrome P450-dependent NADPH cytochrome c reductase (NADPH red) as phase I enzyme, (2) glutathione S-transferase as phase II enzyme and (3) the acetylcholinesterase activity as neurotoxicity marker. Oxidative stress was evaluated using catalase activity and malondialdehyde accumulation. For each biomarker, a discriminatory factor was calculated and a response index was allocated. For each site, a multi-marker pollution index was calculated as the sum of the response index of each of the five more discriminating biomarkers. The results show differences between sites compared with the reference samples. The multi-marker approach confirms that worms from Bizerta and Mahress have been submitted to highly polluted environment. Mahress shows the highest multi-marker pollution index, indicating a highly contamination status.     

Building Local Community Commitment to Wetlands Restoration: A Case Study of the Cache River Wetlands in Southern Illinois, USA

Natural resource professionals are increasingly faced with the challenges of cultivating community-based support for wetland ecosystem restoration. While extensive research efforts have been directed toward understanding the biophysical dimensions of wetland conservation, the literature provides less guidance on how to successfully integrate community stakeholders into restoration planning. Therefore, this study explores the social construction of wetlands locally, and community members’ perceptions of the wetland restoration project in the Cache River Watershed of southern Illinois, where public and private agencies have partnered together to implement a large-scale wetlands restoration project. Findings illustrate that the wetlands hold diverse and significant meanings to community members and that community members’ criteria for project success may vary from those identified by project managers. The case study provides managers with strategies for building community commitment such as engaging local citizens in project planning, minimizing local burdens, maximizing local benefits, and reducing uncertainty.     

兰州市西固区土壤中PAHs污染特征及来源解析

为了解石油工业区土壤中PAHs(多环芳烃)的污染特征、来源及潜在危害,选择兰州市西固区为研究区域,系统采集表层土壤样品及部分剖面样品,采用GC-MS检测方法,分析了土壤中PAHs的污染水平与分布、来源及潜在致癌风险. 结果表明:研究区表层(0~20 cm)土壤中w(∑PAHs)(22种PAHs的总质量分数)在535～32 300 μg/kg之间;PAHs在土壤剖面的纵向分布上主要集中在5～10 cm,在0～25 cm范围内变化不明显;表层土壤中PAHs主要以2～3环为主. 相关性分析显示,土壤中w(∑PAHs)与w(TOC)无显著的相关性,表明TOC并非影响土壤中PAHs持留的重要因素. 研究区土壤中PAHs主要来源于石油、生物质和煤炭的燃烧,∑TEQ_BaP (22种PAHs的毒性当量浓度,以苯并芘等效浓度计)平均值为190 μg/kg,表明土壤中PAHs的潜在致癌性较低.      

Climatic design of vernacular housing in different provinces of China

For 2000 years, the inter-connexion between the specific structure of the Chinese eastern climates and the cultural background have produced remarkable vernacular housing types, both well adapted to the local conditions, and reflecting consistent values and knowledge. Stemming from a similar archetypal form, each house plan is translated through the specificity of the climate and resources of its site. One can think that the value and the diversity of this housing stock is due to the combination of the specific structure of the Chinese eastern climates, which creates the contrast of cold-dry winters and hot-humid summers, with the structure of the Ming t'ang, which contains the opposition of the yin and the yang. These two strong factors imprint a substantial cultural and conceptual unity upon all these housing types. Moreover, on the one hand, the geographical variations and, on the other hand, the local building materials generate a large diversity of housing types, of building techniques and of climatic devices which can be observed all around the country. These lessons could be valuable design guidelines from the past for the future.     

Biotic homogenization and differentiation of plant communities in tropical and subtropical forests

Anthropogenic impacts on biodiversity can lead to biotic homogenization (BH) and biotic differentiation (BD). BH is a process of increasing similarity in community composition (including taxonomic, functional, and phylogenetic components), whereas BD is a process of decreasing similarity over space and time. Here, we conducted a systematic review of BH and BD in plant communities in tropical and subtropical forests to identify trends and knowledge gaps. Our bibliometric search in the Web of Science returned 1989 papers, of which 151 matched our criteria and were included in the analysis. The Neotropical region had the largest number of articles, and Brazil was the most represented country with 92 studies. Regarding the type of change, homogenization was more frequent than differentiation (noted in 69.6% of publications). The taxonomic diversity component was measured more often than functional and phylogenetic diversity components. Most studies (75.6%) assessed homogenization and differentiation based on a single observation in time; as opposed to few studies that monitored plant community over multiple years. Forest fragmentation was cited as the main determinant of homogenization and differentiation processes (57.2% of articles). Our results highlight the importance of evaluating community composition over time and more than taxonomic components (i.e., functional and phylogenetic) to advance understanding of homogenization and differentiation. Both processes were scale dependent and not mutually exclusive. As such, future research should consider differentiation as a potential transition phase to homogenization and that potential differences in both processes may depend on the spatial and temporal scale adopted. Understanding the complexity and causes of homogenization and differentiation is essential for biodiversity conservation in a world increasingly affected by anthropogenic disturbances.     

A preliminary validation of a new measure of occupational health and safety

INTRODUCTION: This article describes the validation of an instrument designed to conduct an Occupational Health and Safety (OHS) self-diagnosis using workers observations of tangible facts and actions in the workplace. The instrument puts the emphasis on observable factors that make it possible to act proactively before accidents actually occur. METHOD: Three companies were recruited from the printing sector in Québec based on their OHS performance (low, medium, and high), their interest in the project, and their availability. The master sample was composed of 269 people. Partial least squares (PLS) and vanishing tetrad analyses were used to study the behavior of the formative scales developed. RESULTS: The results indicate that partial revision of the instrument will be necessary to reach a fully satisfying level of validity. With regards to the statistical approach adopted, the use of a macro called CTA-SAS 2.0 developed by Bollen and Ting [Bollen, K.A., & Ting, K.-F. (1993). Confirmatory tetrad analysis. In P.V. Marsden (Ed.), Social methodology.Vol.23 (pp.147-176). Cambridge, MA: Blackwell, 23] has proven to be effective in providing a suitable statistical treatment of the latent formative variables on which our instrument's development is based. CONCLUSION: The results suggest that the instrument appears to be relatively robust and appropriate to diagnose OHS leading measures. IMPACT ON INDUSTRY: In the long run, this instrument will make it possible for companies to draw a more refined picture of OHS evolution, even in the absence of occupational injuries.     

Contamination of Clams with Human Norovirus and a Novel Hepatitis A Virus in Cameroon

Food and Environmental Virology - Shellfish constitute an important protein source but may be contaminated by viruses from various origins. A study performed on clams collected in Cameroon showed a...     

Adolescent driving: Characteristics associated with single-vehicle and injury crashes

The high motor-vehicle crash rate of young drivers may be attributed to both driving inexperience and a greater tendency to engage in risk-taking behavior. This study examines risk-taking behavior, as indicated by single-vehicle crashes and injury crashes, and factors associated with these behaviors, based on measures of demographic, psychosocial, and substance use obtained from high school senior questionnaires. Because previous work indicated different predictors for young men and young women, separate logistic regression analyses were conducted. For young women, propensity toward cigarette use was associated with higher rates of single-vehicle crashes; while race, alcohol misuse, and friends' involvement with alcohol and marijuana were associated with injury crashes. For young men, availability of substances, driving frequency, alcohol misuse, and propensity toward marijuana use were associated with higher rates of single-vehicle crashes. Young men's living situation, availability of substances, and marijuana use were related to injury crashes.