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301.
Iodoacetic acid (IAA) is an unregulated water disinfection byproduct that is an ovarian toxicant. However, the mechanisms of action underlying IAA toxicity in ovarian follicles remain unclear. Thus, we determined whether IAA alters gene expression in ovarian follicles in mice. Adult female mice were dosed with water or IAA (10 or 500 mg/L) in the water for 35-40 days. Antral follicles were collected for RNA-sequencing analysis and sera were collected to measure estradiol. RNA-sequencing analysis identified 1063 differentially expressed genes (DEGs) in the 10 and 500 mg/L IAA groups (false discovery rate FDR < 0.1), respectively, compared to controls. Gene Ontology Enrichment analysis showed that DEGs were involved with RNA processing and regulation of angiogenesis (10 mg/L) and the cell cycle and cell division (500 mg/L). Pathway Enrichment analysis showed that DEGs were involved in the phosphatidylinositol 3-kinase and protein kinase B (PI3K-Akt), gonadotropin-releasing hormone (GnRH), estrogen, and insulin signaling pathways (10 mg/L). Pathway Enrichment analysis showed that DEGs were involved in the oocyte meiosis, GnRH, and oxytocin signaling pathways (500 mg/L). RNA-sequencing analysis identified 809 DEGs when comparing the 500 and 10 mg/L IAA groups (FDR < 0.1). DEGs were related to ribosome, translation, mRNA processing, oxidative phosphorylation, chromosome, cell cycle, cell division, protein folding, and the oxytocin signaling pathway. Moreover, IAA exposure significantly decreased estradiol levels (500 mg/L) compared to control. This study identified key candidate genes and pathways involved in IAA toxicity and can help to further understand the molecular mechanisms of IAA toxicity in ovarian follicles.  相似文献   
302.
This article presents the findings of a survey of farmers' markets customers in the Niagara region of Ontario, Canada. The recent growth of farmers' markets in North America and the association of these markets with local food systems development provoke examination to gain insights into consumer motivations for patronizing these markets, and to then reflect on their potential role within locally oriented and sustainable food production systems. The survey carried out on customers of three Niagara region farmers' markets corroborates previous studies that noted that socioeconomic and cultural factors such as the importance of food freshness, support of local farmers and the local farm economy, and social interaction—embeddedness—are key expressions of people's support and interest in farmers' markets. This work serves to heighten our understanding of consumer attitudes toward direct marketing via farmers' markets, yields useful speculation about these markets and their roles in sustainable local food systems progress, and also raises critical questions about such customer patronage and associated farmers' markets potential in local food system development.  相似文献   
303.
Well-being is a positive physical, mental and social state and has increasingly become an area of interest to researchers and policy-makers internationally. This paper presents results from research that analyses the well-being benefits gained by different sections of society through viewing, engaging with, and accessing woodlands and forests in Britain. We draw on 31 studies undertaken since 2001 and present a meta-analysis of quantitative data and a meta-synthesis of qualitative data to explore the range of benefits and associated activities in woodlands, and their social distribution. We also present a state-of-the-art typology of well-being benefits for woodlands in Britain. The findings illustrate the wide range of well-being benefits gained by different social groups through various forms of engagement with and activities undertaken in woodlands. We illustrate the wide range of meanings and values attached to trees and woodlands across different social groups. The evidence also illustrates how carefully designed and targeted interventions can be particularly effective in enabling and encouraging people to visit woodland sites, to participate or get involved in new activities and, therefore, to realise a range of well-being benefits.  相似文献   
304.
Monitoring was carried out of particulate concentrations whilst simultaneously walking and driving 48 routes in London, UK. Monitoring was undertaken during May and June 2005. Route lengths ranged from 601 to 1351 m, and most routes were travelled in both directions. Individual journey times ranged from 1.5 to 15 min by car (average 3.7 min) and 7.3 to 30 min (average 12.8 min) whilst walking; car trips were therefore repeated up to 5 times for each single walking trip and the results averaged for the route. Car trips were made with windows closed and the ventilation system on a moderate setting. Results show that mean exposures while walking are greatly in excess of those while driving, by a factor 4.7 for the coarse particle mass (PM10-PM2.5), 2.2 for the fine particle mass (PM2.5-PM1), 1.9 for the very fine particle mass (相似文献   
305.
Watercraft collisions account for 25–30% of manatee deaths annually in Florida. Education and outreach interventions for boaters are strategies for reducing manatee mortality. We evaluated the effectiveness of the Manatee Watch program by surveying primary boat users whose boats were approached by Manatee Watch. We compared the attitudes, knowledge, and behavioral intentions of boaters who received Manatee Watch materials with a control group of boaters observed by the Florida Marine Research Institute in Tampa Bay during 1999–2001. Results of the 51-item telephone survey with 499 boaters indicated that the Manatee Watch intervention had little effect on boater’s attitudes, knowledge, and behaviors regarding manatees. However, individual attitude scores were positively correlated with safe boating behaviors in shallow waters including maintaining a slower speed and watching out for manatees. Overall knowledge about manatees was correlated with one manatee-safe boating behavior. To improve efficacy, educators should (a) incorporate evaluation into the planning stages of program development; (b) target messages to influence boaters’ attitudes toward manatees and ecosystem health, and their feelings of ownership and empowerment; (c) facilitate active participation of the boaters; and (d) increase the duration and variety of intervention.  相似文献   
306.
To investigate the effects of moist olive husks (MOH-residues) on soil respiration, microbial biomass, and enzymatic (o-diphenoloxidase, beta-glucosidase, dehydrogenase and alkaline phosphatase) activities, a silty clay soil was incubated with 0 (control), 8 x 10(3) (D), 16 x 10(3) (2D) and 80 x 10(3) (10D) kg ha-1 of MOH-residues on a dry weight basis. Soil respiration and microbial biomass data indicated that the addition of MOH-residues strongly increased microbial activity proportionally to the amounts added. Data of qCO2 suggested that the respiration to biomass ratio of the microbial population was strongly modified by MOH-residues additions during the first 90 days of incubation. The qCO2 data suggested a low efficiency in energy yields from C oxidation during the first 2 months of soil incubation. qFDA seemed to be relatively unaffected for treatments D and 2D as compared to the control, but was significantly lowered by the application of 10D, showing the lowest hydrolytic activity of microbial biomass in this treatment up to 360 days of incubation. o-Diphenoloxidase activity was delayed, and this delay was extended with the addition of larger quantities of MOH-residues. Alkaline phosphatase, beta-glucosidase and dehydrogenase activities were in line with the findings on microbial biomass changes and activities. The biological and biochemical data suggest that the addition of a large quantity of MOH-residues (80 x 10(3) kg ha-1) strongly modifies the soil characteristics affecting the r- and K-strategist populations, and that these changes last for at least the 360 days of incubation. The data also suggest that application rates exceeding 16 x 10(3) kg ha-1 are not recommended until the agro-chemical and -physical functions of the soil are further studied.  相似文献   
307.
Environmental and Ecological Statistics - Within the field of geostatistics, Gaussian processes are a staple for modelling spatial and spatio-temporal data. Statistical literature is rich with...  相似文献   
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