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181.
Environmental Science and Pollution Research - The human coronavirus disease (COVID-19) pandemic is caused by a novel coronavirus; the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2)....  相似文献   
182.
There is an established evidence that exposure to high levels of road traffic noise is associated with elevated risk of coronary heart disease (CHD). The results however have been heterogeneous and mostly inconclusive. The present investigation aimed to examine this association in adult subjects, with a secondary aim of identifying potentially vulnerable sub-populations. Similar studies have never been reported from Indian population. For exposure assessment, the time-weighted road traffic noise indicator, L den, was used as a continuous and categorical predictor. A cross-sectional study was designed, and sociodemographic and lifestyle- and health-related characteristics were recorded for 909 (533 females and 376 males) subjects aged 18–80 years. The respondents living in areas with L den?<?60 dB(A) were designated as the reference group. Odds for self-reported CHD in relation to traffic noise exposure were estimated by univariate and multifactorial logistic regression with adjustments for potential confounders and effect modifiers. The adjusted odds ratio (OR) for self-reported CHD was 1.72 (95 % CI 1.36–2.19) per 5 dB(A) increase of L den (range 55–80 dB(A)). A gender-related risk difference was observed among male (OR 1.47 (1.07–2.02)) and female (OR 1.83 (1.27–2.65)) respondents. A stronger effect for subjects in the age group 55–64 years old was found, with age, residence period, body mass index, and self-reported stress being significant confounders. This study suggests epidemiological evidence that exposure to road traffic noise of L den?>?65 dB(A) may be associated with occurrence of CHD in adult subjects. A trend was observed indicating increasing risk with higher exposure levels. The study results are also suggestive of higher risk of outcome among those with other chronic ailments (diabetes, pulmonary, or renal issues) and residing in the same location in excess of 15 years. Orientation of bedroom windows was identified as a significant effect modifier.  相似文献   
183.
A state-wise assessment of methane (CH(4)) budget for Indian paddies, based on a decadal measurement data across India is presented for the calendar year (CY) 1994, the base year for India's Initial National Communication (NATCOM) to the United Nations Framework Convention on Climate Change (UNFCCC), along with national trend from CY 1979 to 2006. The NATCOM CH(4) emission factors (EFs) for Indian paddy cultivation areas, generally having less than 0.7% of soil organic carbon (SOC), have been estimated as 17.48+/-4 g m(-2) for irrigated continuously flooded (IR-CF), 6.95+/-1.86 g m(-2) for rain-fed drought prone (RF-DP), 19+/-6 g m(-2) for rain-fed flood prone (RF-FP) and deep-water (DW), 6.62+/-1.89 g m(-2) for irrigated intermittently flooded single aeration (IR-IF-SA) and 2.01+/-1.49 g m(-2) for IR-IF multiple aeration (MA) paddy water regimes. The state-wise study for 1994 has indicated national CH(4) budget estimate of 4.09+/-1.19 Tg y(-1) and the trend from 1979 to 2006 was in the range of 3.62+/-1 to 4.09+/-1.19 Tg y(-1). Four higher emitting or "hot spot" states (West Bengal, Bihar, Madhya Pradesh and Uttar Pradesh) have accounted for 53.9% of total CH(4) emission with RF-FP paddy water regime as the major contributor. CH(4) emissions were enhanced by factors such as SOC ( approximately 1.5 times due to increase in SOC by approximately 1.8 times), paddy cultivars (approximately 1.5 times), age of seedlings (approximately 1.4 times), and seasons (approximately 1.8 times in Kharif or monsoon than in Rabi or winter season).  相似文献   
184.
Stable carbon and nitrogen isotopes (delta13C and delta15N) and trace metals (Cd, Zn, Cu, Fe, Se, and Hg) were analysed in the tissues of 46 harbour porpoises (Phocoena phocoena relicta) caught in fishing nets along the Ukrainian coasts between 1997 and 1998. Mean delta13C values differed significantly between male and female harbour porpoises suggesting a trophic segregation between sexes with a more coastal distribution for females at least during their gestation and nursing periods. Hepatic Hg was correlated to delta13C measurements, reflecting a different exposure linked to coastal vs offshore feeding habitats. A geographical comparison with existing data from other regions showed general low levels of Hg, Cd, Cu and Zn in the tissues of harbour porpoises from the Black Sea compared to other Atlantic and North Sea areas.  相似文献   
185.
On percolating water equivalent to 1,156 mm of rainfall, spiromesifen formulation did not leach out of 25-cm long columns, and 62.7 % of this was recovered in 5–10-cm soil depth. In columns treated with the analytical grade, 52.40 % of the recovered spiromesifen was confined to 0–5-cm soil depth, with 0.04 % in leachate fraction, suggesting high adsorption in soil. Results revealed that percolating 400 mL of water, residues of enol metabolite of spiromesifen was detected up to 20–25-cm soil layer, with 23.50 % residues of spiromesifen in this layer and 1.73 % in the leachate fraction indicating that metabolite is more mobile as compared to the parent compound. Results suggested a significant reduction in leaching losses of enol metabolite in amended soil columns with 5 % nano clay, farmyard manure (FYM), and vermicompost. No enol spiromesifen was recovered in the leachate in columns amended with nano clay, vermicompost, and FYM; however, 85.30, 70.5, and 65.40 %, respectively, was recovered from 0–5 cm-soil depth of column after percolating water equivalent to 1,156 mm of rainfall. Spiromesifen formulation is less mobile in sandy loam soil than analytical grade spiromesifen. The metabolite, enol spiromesifen, is relatively more mobile than the parent compound and may leach into groundwater. The study suggested that amendments were very effective in reducing the downward mobility of enol metabolite in soil column. Further, it resulted in greater retention of enol metabolite in the amendment application zone.  相似文献   
186.
Journal of Material Cycles and Waste Management - Earlier studies indicated that the reactive MgO reduces shrinkage crack and porosity, and accelerates the hydration and strength development....  相似文献   
187.
An experiment was conducted to optimise rooting in stem cuttings of the mangrove tree species Bruguiera parviflora, Cynometra iripa, Excoecaria agallocha, Heritiera fomes and Thespesia populnea. Cuttings were girdled or non-girdled and treated with the auxins indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and naphthalene-acetic acid (NAA) and amylase, IAA-oxidase, peroxidase and polyphenol oxidase activities were measured. The best rooting performance (in terms of root number) was in stem cuttings of E. agallocha followed by C. iripa and H. fomes when treated with IBA + NAA. IAA and IBA combinations were more effective in T. populnea and B. parvifolia. Variations in rooting response were markedly reflected in amylase, IAA-oxidase, peroxidase and polyphenol oxidase activities. Sharp increases in amylase and polyphenol-oxidase activities were associated with enhanced rooting in E. agallocha, C. iripa and H. fomes. On the contrary, lowered IAA-oxidase and peroxidase activities favoured rooting in T. populnea and B. parviflora. A higher number of roots occurred in pre-girdled cuttings in comparison to non-girdled cuttings. Received: 30 March 1999 / Accepted: 6 October 1999  相似文献   
188.
This research paper aims at establishing baseline PM10 and PM2.5 concentration levels, which could be effectively used to develop and upgrade the standards in air pollution in developing countries. The relative contribution of fine fractions (PM2.5) and coarser fractions (PM10-2.5) to PM10 fractions were investigates in a megacity which is overcrowded and congested due to lack of road network and deteriorated air quality because of vehicular pollution. The present study was carried out during the winter of 2002. The average 24h PM10 concentration was 304 μg/m3, which is 3 times more than the Indian National Ambient Air Quality Standards (NAAQS) and higher PM10 concentration was due to fine fraction (PM2.5) released by vehicular exhaust. The 24h average PM2.5 concentration was found 179 μg/m3, which is exceeded USEPA and EU standards of 65 and 50 μg/m3 respectively for the winter. India does not have any PM2.5 standards. The 24 h average PM10-2.5 concentrations were found 126 μg/m3. The PM2.5 constituted more than 59% of PM10 and whereas PM10-PM2.5 fractions constituted 41% of PM10. The correlation between PM10 and PM2.5 was found higher as PM2.5 comprised major proportion of PM10 fractions contributed by vehicular emissions.  相似文献   
189.
Journal of Polymers and the Environment - Nowadays when control of environmental toxicity is a matter of concern, the focus of the researchers is to find an eco-friendly process. Considering the...  相似文献   
190.
Objective: Crash reports contain precoded structured data fields and a crash narrative that can be a source of rich information not included in the structured data. The narrative can be useful for identifying vulnerable roadway users, such as agricultural workers. However, using the narratives often requires manual reviews that are time consuming and costly. The objective of this research was to develop a simple and relatively inexpensive, semi-automated tool for screening crash narratives and expediting the process of identifying crashes with specific characteristics, such as agricultural crashes.

Methods: Crash records for Louisiana from 2010 to 2015 were obtained from the Louisiana Department of Transportation (LaDOTD). Records with narratives were extracted and stratified by vehicle type. The majority of analyses focused on a vehicle type of farm equipment (Type T). Two keyword lists, an inclusion list and an exclusion list, were created based on the published literature, subject-matter experts, and findings from a pilot project. Next, a semi-automated tool was developed in Microsoft Excel to identify agricultural crashes. Lastly, the tool’s performance was assessed using a gold standard set of agricultural narratives identified through manual review.

Results: The tool reduced the search space (e.g., number of narratives that need manual review) for narratives requiring manual review from 6.7 to 59.4% depending on the research question. Sensitivity was high, with 96.1% of agricultural crash narratives being correctly classified. Of the gold standard agricultural narratives, 58.3% included an equipment keyword and 72.8% included a farm equipment brand.

Conclusion: This article provides information on how crash narratives can supplement structured crash data. It also provides an easy-to-implement method to facilitate incorporating narratives into safety research along with keyword lists for identifying agricultural crashes.  相似文献   

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