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41.

Introduction

Construction is among the most dangerous industries in the United States accounting for thousands of fatalities every year. Although there is data available on high risk work types and areas, the project-level detail is not readily available.

Method

This paper uses the accident investigation reports to categorize project types and presents project level analysis of 350 fatal accidents for special trade contractors.

Results

The results showed that Residential and Commercial projects lead the fatalities where Falls are observed as the leading cause. However, when the fatality causes and project categories are analyzed for each work type, the results showed different fatality cause proportions for each project type.

Impact on Industry

Project level analysis approach has a direct impact on identifying high risk work types and areas for special trade contractors by making it possible to focus the prevention and intervention efforts more accurately, while highlighting training and education needs.  相似文献   
42.
Abstact Aboveground biomass, aboveground litterfall, and leaf litter decomposition of five indigenous tree stands (pure stands ofPinus brutia,Pinus nigra,Cedrus libani,Juniperus excelsa, and a mixed stand ofAbies cilicica,P. nigra, andC. libani) were measured in an eastern Mediterranean evergreen needleleaf forest of Turkey. Measurements were converted to regional scale estimates of carbon (C) stocks and fluxes of forest ecosystems, based on general non-site-specific allometric relationships. Mean C stock of the conifer forests was estimated as 97.8± 79 Mg C ha−1consisting of 83.0 ± 67 Mg C ha−1in the aboveground and 14.8 ± 12 Mg C ha−1in the belowground biomass. The forest stands had mean soil organic carbon (SOC) and nitrogen (SON) stocks of 172.0 ± 25.7 Mg C ha−1and 9.2 ± 1.2 Mg N ha−1, respectively. Mean total monthly litterfall was 376.2± 191.3 kg C ha−1, ranging from 641 ± 385 kg C ha−1forPinus brutiato 286 ± 82 kg C ha−1forCedrus libani. Decomposition rate constants (k) for pine needles were 0.0016 forCedrus libani, 0.0009 forPinus nigra, 0.0006 for the mixed stand, and 0.0005 day−1forPinus brutiaand Juniperus excelsa. Estimation of components of the C budgets revealed that the forest ecosystems were net C sinks, with a mean sequestration rate of 2.0 ± 1.1 Mg C ha−1 yr−1ranging from 3.2 ± 2 Mg C ha−1forPinus brutiato 1.6 ± 0.6 Mg C ha−1forCedrus libani. Mean net ecosystem productivity (NEP) resulted in sequestration of 98.4 ± 54.1 Gg CO2 yr−1from the atmosphere when extrapolated for the entire study area of 134.2 km2(Gg = 109 g). The quantitative C data from the study revealed the significance of the conifer Mediterranean forests as C sinks  相似文献   
43.
Organically produced, harvested, and dried fruit samples bought at organic markets in Kayseri, Turkey have been analyzed for their trace element contents. In the determinations, flame atomic absorption spectrometer (FAAS) was used. This pilot study is the first to be performed for organically produced, harvested, and dried fruit samples from Kayseri, Turkey. The copper, iron, manganese, and zinc concentrations were found to be 1.6–15.5, 10.3–144, 23.0–211, and 23.3–91.6 μg/g, respectively. The cobalt, lead, cadmium, chromium, and nickel concentrations in all analyzed organic fruit samples were below the quantification limits of FAAS. SRM 1570A spinach leaves and SRM 1515 apple leaves were used to check the accuracy of the procedure. The results for the dried fruit samples found in this work were compared with the values from some studies from the world. The results found in the presented work may also be useful for future studies about organically produced, harvested, and dried fruit samples.  相似文献   
44.
Pathogenic and/or opportunistic fungal species are major causes of nosocomial infections, especially in controlled environments where immunocompromised patients are hospitalized. Indoor fungal contamination in hospital air is associated with a wide range of adverse health effects. Regular determination of fungal spore counts in controlled hospital environments may help reduce the risk of fungal infections. Because infants have inchoate immune systems, they are given immunocompromised patient status. The aim of the present study was to evaluate culturable airborne fungi in the air of hospital newborn units in the Thrace, Marmara, Aegean, and Central Anatolia regions of Turkey. A total of 108 air samples were collected seasonally from newborn units in July 2012, October 2012, January 2013, and April 2013 by using an air sampler and dichloran 18% glycerol agar (DG18) as isolation media. We obtained 2593 fungal colonies comprising 370 fungal isolates representing 109 species of 28 genera, which were identified through multi-loci gene sequencing. Penicillium, Aspergillus, Cladosporium, Talaromyces, and Alternaria were the most abundant genera identified (35.14, 25.40, 17.57, 2.70, and 6.22% of the total, respectively).  相似文献   
45.
In this study, anaerobic treatability of diluted chicken manure (with an influent feed ratio of 1 kg of fresh chicken manure to 6 L of tap water) was investigated in a lab-scale anaerobic sludge bed (ASB) reactor inoculated with granular seed sludge. The ASB reactor was operated at ambient temperature (17–25°C) in order to avoid the need of external heating up to higher operating temperatures (e.g., up to 35°C for mesophilic digestion). Since heat requirement for raising the temperature of incoming feed for digestion is eliminated, energy recovery from anaerobic treatment of chicken manure could be realized with less operating costs. Average biogas production rates were calculated ca. 210 and 242 L per kg of organic matter removed from the ASB reactor at average hydraulic retention times (HRTs) of 13 and 8.6 days, respectively. Moreover, average chemical oxygen demand (COD) removal of ca. 89% was observed with suspended solids removal more than 97% from the effluent of the ASB reactor. Influent ammonia, on the other hand, did not indicate any free ammonia inhibition due to dilution of the raw manure while pH and alkalinity results showed stability during the study. Microbial quantification results indicated that as the number of bacterial community decreased, the amount of Archaea increased through the effective digestion volume of the ASB reactor. Moreover, the number of methanogens displayed an uptrend like archaeal community and a strong correlation (?0.645) was found between methanogenic community and volatile fatty acid (VFA) concentration especially acetate.  相似文献   
46.
This study investigates the assessment of uncertainty contribution in projected changes of high and low flows from parameterization of a hydrological model and inputs of ensemble regional climate models (RCM). An ensemble of climate projections including 15 global circulation model (GCM)/RCM combinations and two bias corrections (change factor (CF) and bias correction in mean (BC)) was used to generate streamflow series for a reference and future period using the Hydrologiska Byråns Vattenbalansavdelning (HBV) model with the 25 best-fit parameter sets based on four objective functions. The occurrence time of high flows is also assessed through seasonality index calculation. Results indicated that the inputs of hydrological model from ensemble climate models accounts for greater contribution to the uncertainty related to projected changes in high flows comparing to the contribution from hydrological model parameterization. However, the uncertainty contribution is opposite for low flows, particularly for CF method. Both CF and BC increases the total mean variance of high and low flows. The variability in the occurrence time of high flows through RCMs is greater than the variability resulted from hydrological model parameters with and without statistical downscaling. The CF provides more accurate timing than BC and it shows the most pronounced changes in flood seasonality.  相似文献   
47.
Beet soilborne pomovirus (BSBV) is an important soilborne virus disease in growing areas of sugar beet. BSBV was transmitted by Polymyxa betae Keskin. Effects of azadirachtin on BSBV and soil biological properties were studied under a greenhouse. The presence of BSBV was tested in soil samples using bait plant test and triple antibody sandwich-enzyme-linked immunosorbent assay (TAS-ELISA). The concentration of BSBV in sugar beet roots was significantly reduced by the application of azadirachtin to the soils. TAS-ELISA absorption values in 1.52, 3.04, and 7.60 ppm were lower than that 0.38 and 0.76 ppm of azadirachtin. Furthermore, in this study, it was determined the 0.38, 0.76, and 1.52 ppm doses of azadirachtin in soils had high amounts of soil biological properties (Cmic, BSR, DHA), while the 3.04 and 7.60 ppm doses had no statistical significance compared to the control treatments.  相似文献   
48.
In this study, a comparative thermodynamic performance analysis of cascade system (CCS) for cooling and heating applications is presented and compared for different refrigerant couples. The CCS consists of the low-temperature cycle (LTC) and high-temperature cycle (HTC). The CO2 was used as working fluid in LTC, whereas the HFE 7000, R134a, R152a, R32, R1234yf, and R365mfc refrigerants were used in HTC. The heating and cooling coefficients of performance (COPht, COPcl) and exergy efficiency of CCS are investigated parametrically according to various factors such as the evaporator, condenser, and reference temperatures. After thermodynamic analyses are completed, the COPcl of CCS is obtained as 1.802, 1.806, 1.826, 1.769, 1.777, and 1.835 for CO2-HFE7000, CO2-R134a, CO2-R152a, CO2-R32, CO2-R1234yf, and CO2-365mfc refrigerant couples, respectively. Furthermore, the heat exchanger has the highest exergy destruction rate, whereas the expansion valves have the lowest of exergy destruction rate.  相似文献   
49.
Most of the oxalotrophic bacteria are facultative methylotrophs and play important ecological roles in soil fertility and cycling of elements. This study gives a detailed picture of the taxonomy and diversity of these bacteria and provides new information about the taxonomical variability within the genus Methylobacterium. Twelve mesophilic, pink-pigmented, and facultatively methylotrophic oxalate-oxidizing strains were included in this work that had been previously isolated from the soil and some plant tissues by the potassium oxalate enrichment method. The isolates were characterized using biochemical tests, cellular lipid profiles, spectral characteristics of carotenoid pigments, G+C content of the DNA, and 16S rDNA sequencing. The taxonomic similarities among the strains were analyzed using the simple matching (S SM) and Jaccard (S J) coefficients, and the UPGMA clustering algorithm. The phylogenetic position of the strains was inferred by the neighbor-joining method on the basis of the 16S rDNA sequences. All isolates were Gram-negative, facultatively methylotrophic, oxidase and catalase positive, and required no growth factors. Based on the results of numerical taxonomy, the strains formed four closely related clusters sharing ≥85% similarity. Analysis of the 16S rDNA sequences demonstrated that oxalotrophic, pink-pigmented, and facultatively methylotrophic strains could be identified as members of the genus Methylobacterium. Except for M. variabile and M. aquaticum, all of the Methylobacterium type strains tested had the ability of oxalate utilization. Our results indicate that the capability of oxalate utilization seems to be an uncommon trait and could be used as a valuable taxonomic criterion for differentiation of Methylobacterium species.  相似文献   
50.
Selvi M  Gül A  Yilmaz M 《Chemosphere》2003,52(1):259-263
The 96-h LC(50) value of cadmium chloride (CdCl(2).H(2)O), a metal salt widely used in industry, was determined in the water frog (Rana ridibunda Pallas, 1771). The experiments were conducted in two series and a total of 140 frogs were used to determine acute toxicity. In addition, behavioral changes in the water frog were determined for each cadmium chloride concentration. Data obtained from the cadmium chloride investigation were evaluated by using the probit analysis statistical method and the 96 h LC(50) value for water frog was estimated to be 51.2 mg/l.  相似文献   
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