Sample records for factors affecting metal

  1. Factors affecting fixation of heavy metals in solidified/stabilized matrix: a review.

    PubMed

    Malviya, Rachana; Chaudhary, Rubina

    2010-07-01

    In this paper, an effort has been made to understand the factors, which affect fixation of heavy metals in solidified/stabilized matrix. Various aspects related to the solidification/stabilization of different heavy metals (Ar, Ba, Cu, Cr, Pb, Zn, Hg) are reviewed. A comparative study of different binders for the fixation of each metal has also been carried out to suggest the most suitable binder, pretreatment required for the metal. Valence, speciation, pH and other factors are also considered while reviewing metal retention capacity of different matrix.

  2. Biologics formulation factors affecting metal leachables from stainless steel.

    PubMed

    Zhou, Shuxia; Schöneich, Christian; Singh, Satish K

    2011-03-01

    An area of increasing concern and scientific scrutiny is the potential contamination of drug products by leachables entering the product during manufacturing and storage. These contaminants may either have a direct safety impact on the patients or act indirectly through the alteration of the physicochemical properties of the product. In the case of biotherapeutics, trace amounts of metal contaminants can arise from various sources, but mainly from contact with stainless steel (ss). The effect of the various factors, buffer species, solution fill volume per unit contact surface area, metal chelators, and pH, on metal leachables from contact with ss over time were investigated individually. Three major metal leachables, iron, chromium, and nickel, were monitored by inductively coupled plasma-mass spectrometry because they are the major components of 316L ss. Iron was primarily used to evaluate the effect of each factor since it is the most abundant. It was observed that each studied factor exhibited its own effect on metal leachables from contact with ss. The effect of buffer species and pH exhibited temperature dependence over the studied temperature range. The metal leachables decreased with the increased fill volume (mL) per unit contact ss surface area (cm(2)) but a plateau was achieved at approximately 3 mL/cm(2). Metal chelators produced the strongest effect in facilitating metal leaching. In order to minimize the metal leachables and optimize biological product stability, each formulation factor must be evaluated for its impact, to balance its risk and benefit in achieving the target drug product shelf life. © 2011 American Association of Pharmaceutical Scientists

  3. Factors Affecting the Levels of Heavy Metals in Juices Processed with Filter Aids.

    PubMed

    Wang, Zhengfang; Jackson, Lauren S; Jablonski, Joseph E

    2017-06-01

    This study investigated factors that may contribute to the presence of arsenic and other heavy metals in apple and grape juices processed with filter aids. Different types and grades of filter aids were analyzed for arsenic, lead, and cadmium with inductively coupled plasma-tandem mass spectrometry. Potential factors affecting the transfer of heavy metals to juices during filtration treatments were evaluated. Effects of washing treatments on removal of heavy metals from filter aids were also determined. Results showed that diatomaceous earth (DE) generally contained a higher level of arsenic than perlite, whereas perlite had a higher lead content than DE. Cellulose contained the lowest level of arsenic among the surveyed filter aids. All samples of food-grade filter aids contained arsenic and lead levels that were below the U.S. Pharmacopeia and National Formulary limits of 10 ppm of total leachable arsenic and lead for food-grade DE filter aids. Two samples of arsenic-rich (>3 ppm) food-grade filter aids raised the level of arsenic in apple and grape juices during laboratory-scale filtration treatments, whereas three samples of low-arsenic (<1 ppm) food-grade filter aids did not affect arsenic levels in filtered juices. Filtration tests with simulated juices (pH 2.9 to 4.1, Brix [°Bx] 8.2 to 18.1, total suspended solids [TSS] 0.1 to 0.5%) showed that pH or sugar content had no effect on arsenic levels of filtered juices, whereas arsenic content of filtered juice was elevated when higher amounts of filter aid were used for filtration. Authentic unfiltered apple juice (pH 3.6, °Bx 12.9, TSS 0.4%) and grape juice (pH 3.3, °Bx 16.2, TSS 0.05%) were used to verify results obtained with simulated juices. However, body feed ratio did not affect the arsenic content of filtered authentic juices. Washing treatments were effective at reducing arsenic, but not cadmium or lead, concentrations in a DE filter aid. This study identified ways to reduce the amount of arsenic

  4. Biotherapeutic formulation factors affecting metal leachables from stainless steel studied by design of experiments.

    PubMed

    Zhou, Shuxia; Evans, Brad; Schöneich, Christian; Singh, Satish K

    2012-03-01

    Trace amounts of metals are inevitably present in biotherapeutic products. They can arise from various sources. The impact of common formulation factors such as protein concentration, antioxidant, metal chelator concentration and type, surfactant, pH, and contact time with stainless steel on metal leachables was investigated by a design of experiments approach. Three major metal leachables, iron, chromium, and nickel were monitored by inductively coupled plasma-mass spectrometry. It was observed that among all the tested factors, contact time, metal chelator concentration, and protein concentration were statistically significant factors with higher temperature resulting in higher levels of leached metals. Within a pH range of 5.5-6.5, solution pH played a minor role for chromium leaching at 25°C. No statistically significant difference was observed due to type of chelator, presence of antioxidant, or surfactant. In order to optimize a biotherapeutic formulation to achieve a target drug product shelf life with acceptable quality, each formulation component must be evaluated for its impact.

  5. Factors affecting the strength of multipass low-alloy steel weld metal

    NASA Technical Reports Server (NTRS)

    Krantz, B. M.

    1972-01-01

    The mechanical properties of multipass high-strength steel weld metals depend upon several factors, among the most important being: (1) The interaction between the alloy composition and weld metal cooling rate which determines the as-deposited microstructure; and (2) the thermal effects of subsequent passes on each underlying pass which alter the original microstructure. The bulk properties of a multipass weld are therefore governed by both the initial microstructure of each weld pass and its subsequent thermal history. Data obtained for a high strength low alloy steel weld metal confirmed that a simple correlation exists between mechanical properties and welding conditions if the latter are in turn correlated as weld cooling rate.

  6. Heavy Metal Concentrations in Soils and Factors Affecting Metal Uptake by Plants in the Vicinity of a Korean Cu-W Mine.

    PubMed

    Jung, Myung Chae

    2008-04-04

    Heavy metal concentrations were measured in soils and plants in and around a copper-tungsten mine in southeast Korea to investigate the influence of past base metal mining on the surface environment. The results of chemical analysis indicate that the heavy metals in soils decreased with distance from the source, controlled mainly by water movement and topography. The metal concentrations measured in plant species generally decreased in the order; spring onions > soybean leaves > perilla leaves » red pepper > corn grains » jujube grains, although this pattern varied moderately between different elements. The results agree with other reports that metal concentrations in leaves are usually much higher than those in grain. Factors influencing the bioavailability of metals and their occurrences in crops were found as soil pH, cation exchange capacity, organic matter content, soil texture, and interaction among the target elements. It is concluded that total metal concentrations in soils are the main controls on their contents in plants. Soil pH was also an important factor. A stepwise linear multiple regression analysis was also conducted to identify the dominant factors influencing metal uptake by plants. Metal concentrations in plants were also estimated by computer-aided statistical methods.

  7. Factors affecting the shear bond strength of metal and ceramic brackets bonded to different ceramic surfaces.

    PubMed

    Abu Alhaija, Elham S J; Abu AlReesh, Issam A; AlWahadni, Ahed M S

    2010-06-01

    The aims of this study were to evaluate the shear bond strength (SBS) of metal and ceramic brackets bonded to two different all-ceramic crowns, IPS Empress 2 and In-Ceram Alumina, to compare the SBS between hydrofluoric acid (HFA), phosphoric acid etched, and sandblasted, non-etched all-ceramic surfaces. Ninety-six all-ceramic crowns were fabricated resembling a maxillary left first premolar. The crowns were divided into eight groups: (1) metal brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (2) metal brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (3) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched IPS Empress 2 crowns; (4) ceramic brackets bonded to sandblasted 9.6 per cent HFA-etched In-Ceram crowns; (5) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched IPS Empress 2 crowns; (6) metal brackets bonded to sandblasted 37 per cent phosphoric acid-etched In-Ceram crowns; (7) metal brackets bonded to sandblasted, non-etched IPS Empress 2 crowns; and (8) metal brackets bonded to sandblasted, non-etched In-Ceram crowns. Metal and ceramic orthodontic brackets were bonded using a conventional light polymerizing adhesive resin. An Instron universal testing machine was used to determine the SBS at a crosshead speed of 0.1 mm/minute. Comparison between groups was performed using a univariate general linear model and chi-squared tests. The highest mean SBS was found in group 3 (120.15 +/- 45.05 N) and the lowest in group 8 (57.86 +/- 26.20 N). Of all the variables studied, surface treatment was the only factor that significantly affected SBS (P < 0.001). Acid etch application to sandblasted surfaces significantly increased the SBS in groups 1, 2, 5, and 6. The SBS of metal brackets debonded from groups 1, 3, and 5 were not significantly different from those of groups 2, 4, and 6. All debonded metal brackets revealed a similar pattern of bond failure at the adhesive-restorative interface

  8. Heavy metals accumulation affects bone microarchitecture in osteoporotic patients.

    PubMed

    Scimeca, Manuel; Feola, Maurizio; Romano, Lorenzo; Rao, Cecilia; Gasbarra, Elena; Bonanno, Elena; Brandi, Maria Luisa; Tarantino, Umberto

    2017-04-01

    Bone metabolism is affected by mechanical, genetic, and environmental factors and plays a major role in osteoporosis. Nevertheless, the influence of environmental pollution on the occurrence of osteoporosis is still unclear and controversial. In this context, heavy metals are the most important pollutants capable to affect bone mass. The aim of this study was to investigate whether heavy metals accumulation in bone tissues could be related to the altered bone metabolism and architecture of osteoporotic patients. To this end, we analyzed 25 bone head biopsies osteoporotic patients and 25 bone head biopsies of osteoarthritic patients. Moreover we enrolled 15 patients underwent hip arthroplasty for high-energy hip fracture or osteonecrosis of the femoral head as a control group. Bone head biopsies were studied by BioQuant-osteo software, scanning electron microscopy and Energy Dispersive X-ray microanalysis. We found a prevalence of lead, cadmium and chromium accumulation in osteoporotic patients. Noteworthy, high levels of sclerostin, detected by immunohistochemistry, correlate with the accumulation of heavy metal found in the bone of osteoporotic patients, suggesting a molecular link between heavy metal accumulation and bone metabolism impairment. In conclusion, the presence of heavy metals into bone shed new light on the comprehension of the pathogenesis of osteoporosis since these elements could play a non redundant role in the development of osteoporosis at cellular/molecular and epigenetic level. Nevertheless, in vivo and in vitro studies need to better elucidate the molecular mechanism in which heavy metals can participate to osteoporosis. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1333-1342, 2017. © 2016 Wiley Periodicals, Inc.

  9. Mixtures of herbicides and metals affect the redox system of honey bees.

    PubMed

    Jumarie, Catherine; Aras, Philippe; Boily, Monique

    2017-02-01

    The increasing loss of bee colonies in many countries has prompted a surge of studies on the factors affecting bee health. In North America, main crops such as maize and soybean are cultivated with extensive use of pesticides that may affect non-target organisms such as bees. Also, biosolids, used as a soil amendment, represent additional sources of metals in agroecosystems; however, there is no information about how these metals could affect the bees. In previous studies we investigated the effects of environmentally relevant doses of herbicides and metals, each individually, on caged honey bees. The present study aimed at investigating the effects of mixtures of herbicides (glyphosate and atrazine) and metals (cadmium and iron), as these mixtures represent more realistic exposure conditions. Levels of metal, vitamin E, carotenoids, retinaldehyde, at-retinol, retinoic acid isomers (9-cis RA, 13-cis RA, at-RA) and the metabolites 13-cis-4-oxo-RA and at-4-oxo-RA were measured in bees fed for 10 days with contaminated syrup. Mixtures of herbicides and cadmium that did not affect bee viability, lowered bee α- and β-carotenoid contents and increased 9-cis-RA as well as 13-cis-4-oxo-RA without modifying the levels of at-retinol. Bee treatment with either glyphosate, a combination of atrazine and cadmium, or mixtures of herbicides promoted lipid peroxidation. Iron was bioconcentrated in bees and led to high levels of lipid peroxidation. Metals also decreased zeaxanthin bee contents. These results show that mixtures of atrazine, glyphosate, cadmium and iron may affect different reactions occurring in the metabolic pathway of vitamin A in the honey bee. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Factors Affecting the Inclusion Potency for Acicular Ferrite Nucleation in High-Strength Steel Welds

    NASA Astrophysics Data System (ADS)

    Kang, Yongjoon; Jeong, Seonghoon; Kang, Joo-Hee; Lee, Changhee

    2016-06-01

    Factors affecting the inclusion potency for acicular ferrite nucleation in high-strength weld metals were investigated and the contribution of each factor was qualitatively evaluated. Two kinds of weld metals with different hardenabilities were prepared, in both, MnTi2O4-rich spinel formed as the predominant inclusion phase. To evaluate the factors determining the inclusion potency, the inclusion characteristics of size, phase distribution in the multiphase inclusion, orientation relationship with ferrite, and Mn distribution near the inclusion were analyzed. Three factors affecting the ferrite nucleation potency of inclusions were evaluated: the Baker-Nutting (B-N) orientation relationship between ferrite and the inclusion; the formation of an Mn-depleted zone (MDZ) near the inclusion; and the strain energy around the inclusion. Among these, the first two factors were found to be the most important. In addition, it was concluded that the increased chemical driving force brought about by the formation of an MDZ contributed more to the formation of acicular ferrite in higher-strength weld metals, because the B-N orientation relationship between ferrite and the inclusion was less likely to form as the transformation temperature decreased.

  11. Short-term acute hypercapnia affects cellular responses to trace metals in the hard clams Mercenaria mercenaria.

    PubMed

    Ivanina, Anna V; Beniash, Elia; Etzkorn, Markus; Meyers, Tiffany B; Ringwood, Amy H; Sokolova, Inna M

    2013-09-15

    Estuarine and coastal habitats experience large fluctuations of environmental factors such as temperature, salinity, partial pressure of CO2 ( [Formula: see text] ) and pH; they also serve as the natural sinks for trace metals. Benthic filter-feeding organisms such as bivalves are exposed to the elevated concentrations of metals in estuarine water and sediments that can strongly affect their physiology. The effects of metals on estuarine organisms may be exacerbated by other environmental factors. Thus, a decrease in pH caused by high [Formula: see text] (hypercapnia) can modulate the effects of trace metals by affecting metal bioavailability, accumulation or binding. To better understand the cellular mechanisms of interactions between [Formula: see text] and trace metals in marine bivalves, we exposed isolated mantle cells of the hard clams (Mercenaria mercenaria) to different levels of [Formula: see text] (0.05, 1.52 and 3.01 kPa) and two major trace metal pollutants - cadmium (Cd) and copper (Cu). Elevated [Formula: see text] resulted in a decrease in intracellular pH (pHi) of the isolated mantle cells from 7.8 to 7.4. Elevated [Formula: see text] significantly but differently affected the trace metal accumulation by the cells. Cd uptake was suppressed at elevated [Formula: see text] levels while Cu accumulation has greatly accelerated under hypercapnic conditions. Interestingly, at higher extracellular Cd levels, labile intracellular Cd(2+) concentration remained the same, while intracellular levels of free Zn(2+) increased suggesting that Cd(2+) substitutes bound Zn(2+) in these cells. In contrast, Cu exposure did not affect intracellular Zn(2+) but led to a profound increase in the intracellular levels of labile Cu(2+) and Fe(2+). An increase in the extracellular concentrations of Cd and Cu led to the elevated production of reactive oxygen species under the normocapnic conditions (0.05 kPa [Formula: see text] ); surprisingly, this effect was mitigated in

  12. Factors affecting hazardous waste solidification/stabilization: a review.

    PubMed

    Malviya, Rachana; Chaudhary, Rubina

    2006-09-01

    Solidification/stabilization is accepted as a well-established disposal technique for hazardous waste. As a result many different types of hazardous wastes are treated with different binders. The S/S products have different property from waste and binders individually. The effectiveness of S/S process is studied by physical, chemical and microstructural methods. This paper summarizes the effect of different waste stream such as heavy metals bearing sludge, filter cake, fly ash, and slag on the properties of cement and other binders. The factors affecting strength development is studied using mix designs, including metal bearing waste alters the hydration and setting time of binders. Pore structure depends on relative quantity of the constituents, cement hydration products and their reaction products with admixtures. Carbonation and additives can lead to strength improvement in waste-binder matrix.

  13. Preparation and properties of chitosan-metal complex: Some factors influencing the adsorption capacity for dyes in aqueous solution.

    PubMed

    Rashid, Sadia; Shen, Chensi; Yang, Jing; Liu, Jianshe; Li, Jing

    2018-04-01

    Chitosan-metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan-metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan-Fe(III) complex prepared by sulfate salts exhibited the best adsorption efficiency (100%) for various dyes in very short time duration (10min), and its maximum adsorption capacity achieved 349.22mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan-metal complex. SO 4 2- ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis process. Additionally, the pH sensitivity and the sensitivity of ionic environment for chitosan-metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan-metal complex can help not only in optimizing its use but also in designing new chitosan-metal based complexes. Copyright © 2017. Published by Elsevier B.V.

  14. Mechanisms of Divalent Metal Toxicity in Affective Disorders

    PubMed Central

    Menon, Archita Venugopal; Chang, JuOae; Kim, Jonghan

    2016-01-01

    Metals are required for proper brain development and play an important role in a number of neurobiological functions. The Divalent Metal Transporter 1 (DMT1) is a major metal transporter involved in the absorption and metabolism of several essential metals like iron and manganese. However, non-essential divalent metals are also transported through this transporter. Therefore, altered expression of DMT1 can modify the absorption of toxic metals and metal-induced toxicity. An accumulating body of evidence has suggested that increased metal stores in the brain are associated with elevated oxidative stress mediated by the ability of metals to catalyze redox reactions, resulting in abnormal neurobehavioral function and the progression of neurodegenerative diseases. Metal overload has also been implicated in impaired emotional behavior, although the underlying mechanisms are not well understood with limited information. The current review focuses on psychiatric dysfunction associated with imbalanced metabolism of metals that are transported by DMT1. The investigations with respect to the toxic effects of metal overload on behavior and their underlying mechanisms of toxicity could provide several new therapeutic targets to treat metal-associated affective disorders. PMID:26551072

  15. Factors affecting the toxicity of trace metals to fertilization success in broadcast spawning marine invertebrates: A review.

    PubMed

    Hudspith, M; Reichelt-Brushett, Amanda; Harrison, Peter L

    2017-03-01

    Significant amounts of trace metals have been released into both nearshore and deep sea environments in recent years, resulting in increased concentrations that can be toxic to marine organisms. Trace metals can negatively affect external fertilization processes in marine broadcast spawners and may cause a reduction in fertilization success at elevated concentrations. Due to its sensitivity and ecological importance, fertilization success has been widely used as a toxicity endpoint in ecotoxicological testing, which is an important method of evaluating the toxicity of contaminants for management planning. Ecotoxicological data regarding fertilization success are available across the major marine phyla, but there remain uncertainties that impair our ability to confidently interpret and analyse these data. At present, the cellular and biochemical events underlying trace metal toxicity in external fertilization are not known. Metal behavior and speciation play an important role in bioavailability and toxicity but are often overlooked, and disparities in experimental designs between studies limit the degree to which results can be synthesised and compared to those of other relevant species. We reviewed all available literature covering cellular toxicity mechanisms, metal toxicities and speciation, and differences in methodologies between studies. We conclude that the concept of metal toxicity should be approached in a more holistic manner that involves elucidating toxicity mechanisms, improving the understanding of metal behavior and speciation on bioavailability and toxicity, and standardizing the fertilization assay methods among different groups of organisms. We identify opportunities to improve the fertilization assay that will allow robust critical and comparative analysis between species and their sensitivities to trace metals during external fertilization, and enable data to be more readily extrapolated to field conditions. Copyright © 2017 Elsevier B.V. All

  16. Characteristics of trace metals in traffic-derived particles in Hsuehshan Tunnel, Taiwan: size distribution, fingerprinting metal ratio, and emission factor

    NASA Astrophysics Data System (ADS)

    Lin, Y.-C.; Tsai, C.-J.; Wu, Y.-C.; Zhang, R.; Chi, K.-H.; Huang, Y.-T.; Lin, S.-H.; Hsu, S.-C.

    2014-05-01

    Traffic emissions are a significant source of airborne particulate matter (PM) in ambient environments. These emissions contain high abundance of toxic metals and thus pose adverse effects on human health. Size-fractionated aerosol samples were collected from May to September 2013 by using micro-orifice uniform deposited impactor (MOUDI). Sample collection was conducted simultaneously at the inlet and outlet sites of Hsuehshan Tunnel in northern Taiwan, which is the second longest freeway tunnel (12.9 km) in Asia. Such endeavor aims to characterize the chemical constituents, size distributions, and fingerprinting ratios, as well as the emission factors of particulate metals emitted by vehicle fleets. A total of 36 metals in size-resolved aerosols were determined through inductively coupled plasma mass spectrometry. Three major groups, namely, tailpipe emissions (Zn, Pb, and V), wear debris (Cu, Cd, Fe, Ga, Mn, Mo, Sb, and Sn), and resuspended dust (Ca, Mg, K, and Rb), of airborne PM metals were categorized on the basis of the results of enrichment factor, correlation matrix, and principal component analysis. Size distributions of wear-originated metals resembled the pattern of crustal elements, which were predominated by super-micron particulates (PM1-10). By contrast, tailpipe exhaust elements such as Zn, Pb, and V were distributed mainly in submicron particles. By employing Cu as a tracer of wear abrasion, several inter-metal ratios, including Fe/Cu (14), Ba/Cu (1.05), Sb/Cu (0.16), Sn/Cu (0.10), and Ga/Cu (0.03), served as fingerprints for wear debris. Emission factor of PM10 mass was estimated to be 7.7 mg vkm-1. The metal emissions were mostly predominated in super-micron particles (PM1-10). Finally, factors that possibly affect particulate metal emissions inside Hsuehshan Tunnel are discussed.

  17. Factors affecting tumor ablation during high intensity focused ultrasound treatment.

    PubMed

    Hassanuddin, Aizan; Choi, Jun-Ho; Seo, Dong-Wan; Ryu, Choong Heon; Kim, Su-Hui; Park, Do Hyun; Lee, Sang Soo; Lee, Sung Koo; Kim, Myung-Hwan

    2014-07-01

    High intensity focused ultrasound (HIFU) utilizes a targeted extracorporeal focused ultrasound beam to ablate neoplastic pancreatic tissue. We used an in vitro model to examine the effects of bone, metallic stents, plastic stents, metal plates, and cyst-like lesions on HIFU treatment. HIFU was delivered to the phantom models implanted with foreign bodies, and the location, shape, and size of the ablated zones were evaluated. Bone and metallic plates reflected the ultrasound beam, shifting the ablation zone from the focal zone to the prefocal area. In the phantoms containing metal stent, plastic stent, and cyst, most of the ablative energy was reflected to the prefocal area by the surface, with the remainder penetrating through the phantom. The area of the ablated margins was significantly larger in size and volume than the intended focal ablation zone. During HIFU therapy, artificial or anatomical barriers could affect the direction of the ultrasound beams, shifting the ablation zone from the focal area to a prefocal site with a larger than expected ablation zone. These factors should be considered prior to HIFU treatment for pancreatic tumors because they could limit ablation success, in addition to causing complications.

  18. Environmental Factors Determining the Accumulation of Metals: Cu, Zn, Mn and Fe in Tissues of Taraxacum sp. sect. Taraxacum.

    PubMed

    Królak, Elżbieta; Marciniuk, Jolanta; Popijantus, Katarzyna; Wasilczuk, Paulina; Kasprzykowski, Zbigniew

    2018-05-19

    The genus Taraxacum is used in the assessment of soil contamination with heavy metals. There are relatively few studies using sections or species representing this genus. The presented research was conducted in Poland on two habitats, varied in terms of nutrients and metals content. The content of selected metals in leaves and roots of Taraxacum sect. Taraxacum was determined. It was found that in the conditions of increased content of metals in the soil, the analysed species representing sect. Taraxacum accumulate higher amounts of metals in their leaves and roots. Factors of translocation of selected metals from roots to leaves of Taraxacum species, representing the Taraxacum section, are affected by i.a. soil reaction and the content of Corg, Ntot. in the soil. No influence of soil properties on metal biological concentration factor was observed.

  19. Factors affecting sign retroreflectivity

    DOT National Transportation Integrated Search

    2001-01-01

    This study was undertaken to better understand the factors that may affect road sign retroreflectivity, specifically age and physical orientation. A better understanding of these factors could provide guidance to ODOT in managing its inventory of roa...

  20. Heavy metal pollution of coal mine-affected agricultural soils in the northern part of Bangladesh.

    PubMed

    Bhuiyan, Mohammad A H; Parvez, Lutfar; Islam, M A; Dampare, Samuel B; Suzuki, Shigeyuki

    2010-01-15

    Total concentrations of heavy metals in the soils of mine drainage and surrounding agricultural fields in the northern part of Bangladesh were determined to evaluate the level of contamination. The average concentrations of Ti, Mn, Zn, Pb, As, Fe, Rb, Sr, Nb and Zr exceeded the world normal averages and, in some cases, Mn, Zn, As and Pb exceeded the toxic limit of the respective metals. Soil pollution assessment was carried out using enrichment factor (EF), geoaccumulation index (I(geo)) and pollution load index (PLI). The soils show significant enrichment with Ti, Mn, Zn, Pb, As, Fe, Sr and Nb, indicating inputs from mining activities. The I(geo) values have revealed that Mn (1.24+/-0.38), Zn (1.49+/-0.58) and Pb (1.63+/-0.38) are significantly accumulated in the study area. The PLIs derived from contamination factors indicate that the distal part of the coal mine-affected area is the most polluted (PLI of 4.02). Multivariate statistical analyses, principal component and cluster analyses, suggest that Mn, Zn, Pb and Ti are derived from anthropogenic sources, particularly coal mining activities, and the extreme proximal and distal parts are heavily contaminated with maximum heavy metals.

  1. Experimental investigation on V isotope equilibrium fractionation factor between metal and silicate melt

    NASA Astrophysics Data System (ADS)

    Zhang, S.; Zhang, H.; Huang, F.

    2017-12-01

    Equilibrium fractionation factors of stable isotopes between metal and silicate melt are of vital importance for understanding the isotope variations within meteorites and planetary bodies. The V isotope composition (reported as δ51V = 1000 × [(51V/50Vsample/51V/50VAA)-1] ) of the bulk silicate Earth (BSE) has been estimated as δ51V = -0.7 ± 0.2‰ (2sd) [1], which is significantly heavier than most meteorites by 1‰ [2]. Such isotopic offset may provide insights for the core formation and core-mantle segregation. Therefore, it is important to understand V isotope equilibrium fractionation factor between silicate melt and metal. Nielsen et al. (2014) [2] had performed 3 experiments using starting materials of pure Fe metal and An50Di28Fo22 composition, revealing no resolvable V isotope fractionation. However, it is not clear whether chemical compositions in the melts can affect V isotope fractionations. Therefore, we experimentally calibrated equilibrium V isotope fractionation between Fe metallic and basaltic melt, with particular focus on the effect of Ni and other light elements. Experiments were performed at 1 GPa and 1600 oC using a 3/4″ end-loaded piston cylinder. The starting materials consisted of 1:1 mixture of pure Fe metal and basaltic composition [3]. The isotope equilibrium was assessed using time series experiments combined with the reverse reaction method. Carbon saturation and C-free experiments were achieved by using graphite and silica capsules, respectively. The Ni series experiments were doped with 6 wt% Ni into the starting Fe metal. The metal and silicate phases of samples were mechanically separated, V was purified using a chromatographic technique, and V isotope ratios were measured using MC-ICP-MS [4]. Carbon saturation, C-free experiments and Ni series experiment all show non-resolvable V isotope fractionation between metal and basaltic melt, which indicates that the presence of C and Ni could not affect V isotope fractionation

  2. Factors affecting cadmium absorbed by pistachio kernel in calcareous soils, southeast of Iran.

    PubMed

    Shirani, H; Hosseinifard, S J; Hashemipour, H

    2018-03-01

    Cadmium (Cd) which does not have a biological role is one of the most toxic heavy metals for organisms. This metal enters environment through industrial processes and fertilizers. The main objective of this study was to determine the relationships between absorbed Cd by pistachio kernel and some of soil physical and chemical characteristics using modeling by stepwise regression and Artificial Neural Network (ANN), in calcareous soils in Rafsanjan region, southeast of Iran. For these purposes, 220 pistachio orchards were selected, and soil samples were taken from two depths of 0-40 and 40-80cm. Besides, fruit and leaf samples from branches with and without fruit were taken in each sampling point. The results showed that affecting factors on absorbed Cd by pistachio kernel which were obtained by regression method (pH and clay percent) were not interpretable, and considering unsuitable vales of determinant coefficient (R 2 ) and Root Mean Squares Error (RMSE), the model did not have sufficient validity. However, ANN modeling was highly accurate and reliable. Based on its results, soil available P and Zn and soil salinity were the most important factors affecting the concentration of Cd in pistachio kernel in pistachio growing areas of Rafsanjan. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Factors affecting construction performance: exploratory factor analysis

    NASA Astrophysics Data System (ADS)

    Soewin, E.; Chinda, T.

    2018-04-01

    The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

  4. Accurate Determination of Coulombic Efficiency for Lithium Metal Anodes and Lithium Metal Batteries

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adams, Brian D.; Zheng, Jianming; Ren, Xiaodi

    Lithium (Li) metal is an ideal anode material for high energy density batteries. However, its low Coulombic efficiency (CE) and formation of dendrites during the plating and stripping processes has hindered its applications in rechargeable Li metal batteries. The accurate measurement of Li CE is a critical factor to predict the cycle life of Li metal batteries, but the measurement of Li CE is affected by various factors that often leads to conflicting values reported in the literature. Here, we investigate various factors that affect the measurement of Li CE and propose a more accurate method of determining Li CE.more » It was also found that the capacity used for cycling greatly affects the stabilization cycles and the average CE. A higher cycling capacity leads to a shorter number of stabilization cycles and higher average CE. With a proper high-concentration ether-based electrolyte, Li metal can be cycled with a high average CE of 99.5 % for over 100 cycles at a high capacity of 6 mAh cm-2 suitable for practical applications.« less

  5. Factors Affecting Medical Service Quality.

    PubMed

    Mosadeghrad, Ali Mohammad

    2014-02-01

    A better understanding of factors influencing quality of medical service can pinpoint better strategies for quality assurance in medical services. This study aimed to identify factors affecting the quality of medical services provided by Iranian physicians. Exploratory in-depth individual interviews were conducted with sixty-four physicians working in various medical institutions in Iran. Individual, organizational and environmental factors enhance or inhibit the quality of medical services. Quality of medical services depends on the personal factors of the physician and patient, and factors pertaining to the healthcare setting and the broader environment. Differences in internal and external factors such as availability of resources, patient cooperation and collaboration among providers affect the quality of medical services and patient outcomes. Supportive leadership, proper planning, education and training and effective management of resources and processes improve the quality of medical services. This article contributes to healthcare theory and practice by developing a conceptual framework for understanding factors that influence medical services quality.

  6. Metal Oxide Gas Sensors: Sensitivity and Influencing Factors

    PubMed Central

    Wang, Chengxiang; Yin, Longwei; Zhang, Luyuan; Xiang, Dong; Gao, Rui

    2010-01-01

    Conductometric semiconducting metal oxide gas sensors have been widely used and investigated in the detection of gases. Investigations have indicated that the gas sensing process is strongly related to surface reactions, so one of the important parameters of gas sensors, the sensitivity of the metal oxide based materials, will change with the factors influencing the surface reactions, such as chemical components, surface-modification and microstructures of sensing layers, temperature and humidity. In this brief review, attention will be focused on changes of sensitivity of conductometric semiconducting metal oxide gas sensors due to the five factors mentioned above. PMID:22294916

  7. [Heavy metal concentration in Nanjing urban soils and their affecting factors].

    PubMed

    Lu, Ying; Gong, Zitong; Zhang, Ganlin; Zhang, Bo

    2004-01-01

    The concentration and source of heavy metals in Nanjing urban soils and their relationships with soil properties were studied. The results indicated that the soils in Nanjing urban were not obviously polluted by Fe, Ni, Co and V, but polluted by Mn, Cr, Cu, Zn, and Pb to a certain extent. The heavy metals were irregularly distributed in soil profiles. Fe, Ni, Co, and V were originated from soil materials, but Cu, Zn, Pb, and Cr were anthropogenic input. Probably, Mn had different origins in different soils. There were positive correlations among Fe, Cr, Ni, Co, and V concentration, and among Cu, Zn, Pb, and Cr concentration. The Fe, Co, V, and Ni concentration were positively correlated with soil clay content and CEC, and the Cu, Zn and Pb concentration were negatively correlated with clay content. There were positive correlations between Cu, Zn, Pb and Cr concentration and organic C content, and between Pb concentration and soil pH.

  8. Development of an all-metal thick film cost affective metallization system for solar cells

    NASA Technical Reports Server (NTRS)

    Ross, B.

    1981-01-01

    An economical thick film solar cell contact for high volume production of low cost silicon solar array modules was investigated. All metal screenable pastes using base metals were studied. Solar cells with junction depths varying by a factor of 3.3, with and without a deposited oxide coating were used. Cells were screened and fired by a two step firing process. Adhesion and metallurgical results are unsatisfactory. No electrical information is obtained due to inadequate contact adhesion.

  9. Factors affecting the protease activity of venom from jellyfish Rhopilema esculentum Kishinouye.

    PubMed

    Li, Cuiping; Yu, Huahua; Liu, Song; Xing, Ronge; Guo, Zhanyong; Li, Pengcheng

    2005-12-15

    In this paper, the effects of some chemical and physical factors such as temperature, pH values, glycerol, and divalent metal cations on the protease activity of venom from jellyfish, Rhopilema esculentum Kishinouye, were assayed. Protease activity was dependent on temperature and pH values. Zn(2+), Mg(2+), and Mn(2+) in sodium phosphate buffer (0.02M, pH 8.0) could increase protease activity. Mn(2+) had the best effects among the three metal cations and the effect was about 20 times of that of Zn(2+) or Mg(2+) and its maximal protease activity was 2.3x10(5)U/mL. EDTA could increase protease activity. PMSF had hardly affected protease activity. O-Phenanthroline and glycerol played an important part in inhibiting protease activity and their maximal inhibiting rates were 87.5% and 82.1%, respectively.

  10. Factors influencing the contents of metals and as in soils around the watershed of Guanting Reservoir, China.

    PubMed

    Xu, Li; Wang, Tieyu; Luo, Wei; Ni, Kun; Liu, Shijie; Wang, Lin; Li, Qiushuang; Lu, Yonglong

    2013-03-01

    Topsoil samples from 61 sites around the Guanting Reservoir, China, were measured for Cu, Zn, Cr, Ni, Cd, Pb and As concentrations. The mean concentrations of Cu, Zn, Cr, Ni, Cd, Pb and As were 16.8, 59.4, 37.8, 18.3, 0.32, 20.1 and 8.67 mg/kg dry weight, respectively. Factors that influence the dynamics of these metals in soils around the watersheds of Beijing reservoirs were examined. The influence of atmospheric deposition, land use, soil texture, soil type and soil chemical parameters on metal contents in soils was investigated. Atmospheric deposition, land use and soil texture were the important factors affecting heavy metal residues. Soil type and soil chemical parameters were also involved in heavy metal retention in soils. The data provided in this study are considered crucial for reservoir remediation, especially since the Guanting Reservoir will serve as one of the main drinking water sources for Beijing in the foreseeable future.

  11. Road traffic emission factors for heavy metals

    NASA Astrophysics Data System (ADS)

    Johansson, Christer; Norman, Michael; Burman, Lars

    Quantifying the emissions and concentrations of heavy metals in urban air is a prerequisite for assessing their health effects. In this paper a combination of measurements and modelling is used to assess the contribution from road traffic emissions. Concentrations of particulate heavy metals in air were measured simultaneously during 1 year at a densely trafficked street and at an urban background site in Stockholm, Sweden. Annual mean concentrations of cadmium were 50 times lower than the EU directive and for nickel and arsenic concentrations were 10 and six times lower, respectively. More than a factor of two higher concentrations was in general observed at the street in comparison to roof levels indicating the strong influence from local road traffic emissions. The only compound with a significantly decreasing trend in the urban background was Pb with 9.1 ng m -3 in 1995/96 compared to 3.4 ng m -3 2003/04. This is likely due to decreased emissions from wear of brake linings and reduced emissions due to oil and coal combustion in central Europe. Total road traffic emission factors for heavy metals were estimated using parallel measurements of NOx concentrations and knowledge of NOx emission factors. In general, the emission factors for the street were higher than reported in road tunnel measurements. This could partly be due to different driving conditions, since especially for metals which are mainly emitted from brake wear, more stop and go driving in the street compared to in road tunnels is likely to increase emissions. Total emissions were compared with exhaust emissions, obtained from the COPERT model and brake wear emissions based on an earlier study in Stockholm. For Cu, Ni and Zn the sum of brake wear and exhaust emissions agreed very well with estimated total emission factors in this study. More than 90% of the road traffic emissions of Cu were due to brake wear. For Ni more than 80% is estimated to be due to exhaust emissions and for Zn around 40% of

  12. Factors Affecting the Capture Efficiency of a Fume Extraction Torch for Gas Metal Arc Welding.

    PubMed

    Bonthoux, Francis

    2016-07-01

    Welding fumes are classified as Group 2B 'possibly carcinogenic' and this prompts to the implementation of local exhaust ventilation (LEV). The fume extraction torch with LEV integrated into the tool is the most attractive solution but its capture efficiency is often disappointing in practice. This study assesses the main parameters affecting fume capture efficiency namely the extraction flow rate, the positioning of the suction openings on the torch, the angle of inclination of the torch to the workpiece during welding, the metal transfer modes, and the welding deposition rate. The theoretical velocity induced by suction, estimated from the extraction flow rate and the position of the suction openings, is the main parameter affecting effectiveness of the device. This is the design parameter and its value should never be <0.25 m s(-1) The angle of the torch relative to the workpiece also has a great deal of influence. To improve efficiency, work station layouts need to favour positions where the torch is held with angles closer to perpendicular (<15°). Welding with high deposition rates (>1.1g s(-1)) and spray transfer leads to low capture efficiency if induced velocities are <0.5 m s(-1) The results of the study can be used in the design of integrated on-torch extraction systems and provide information for fixing system objectives. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  13. Xenopus laevis oocyte maturation is affected by metal chlorides.

    PubMed

    Marin, Matthieu; Slaby, Sylvain; Marchand, Guillaume; Demuynck, Sylvain; Friscourt, Noémie; Gelaude, Armance; Lemière, Sébastien; Bodart, Jean-François

    2015-08-01

    Few studies have been conducted using Xenopus laevis germ cells as oocytes, though these cells offer many advantages allowing both electrophysiological studies and morphological examination. Our aim was to investigate the effects of metal (cadmium, lead, cobalt and zinc) exposures using cell biology approaches. First, cell survival was evaluated with both phenotypical and electrophysiological approaches. Secondly, the effect of metals on oocyte maturation was assessed with morphological observations and electrophysiological recordings. From survival experiments, our results showed that metal chlorides did not affect cell morphology but strongly depolarized X. laevis oocyte resting potential. In addition, cadmium chloride was able to inhibit progesterone-induced oocyte maturation. By contrast, zinc, but also to a lesser extent cadmium, cobalt and lead, were able to enhance spontaneous oocyte maturation in the absence of progesterone stimulation. Finally, electrophysiological recordings revealed that some metal chlorides (lead, cadmium) exposures could disturb calcium signaling in X. laevis oocyte by modifying calcium-activated chloride currents. Our results demonstrated the high sensitivity of X. laevis oocytes toward exogenous metals such as lead and cadmium. In addition, the cellular events recorded might have a predictive value of effects occurring later on the ability of oocytes to be fertilized. Together, these results suggest a potential use of this cellular lab model as a tool for ecotoxicological assessment of contaminated fresh waters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Flood-related contamination in catchments affected by historical metal mining: an unexpected and emerging hazard of climate change.

    PubMed

    Foulds, S A; Brewer, P A; Macklin, M G; Haresign, W; Betson, R E; Rassner, S M E

    2014-04-01

    Floods in catchments affected by historical metal mining result in the remobilisation of large quantities of contaminated sediment from floodplain soils and old mine workings. This poses a significant threat to agricultural production and is preventing many European river catchments achieving a 'good chemical and ecological status', as demanded by the Water Framework Directive. Analysis of overbank sediment following widespread flooding in west Wales in June 2012 showed that flood sediments were contaminated above guideline pollution thresholds, in some samples by a factor of 82. Most significantly, silage produced from flood affected fields was found to contain up to 1900 mg kg(-1) of sediment associated Pb, which caused cattle poisoning and mortality. As a consequence of climate related increases in flooding this problem is likely to continue and intensify. Management of contaminated catchments requires a geomorphological approach to understand the spatial and temporal cycling of metals through the fluvial system. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Factors Affecting Tocopherol Concentrations in Soybean Seeds.

    PubMed

    Carrera, Constanza S; Seguin, Philippe

    2016-12-21

    Soybean seeds contain several health-beneficial compounds, including tocopherols, which are used by the nutraceutical and functional food industries. Soybean tocopherol concentrations are, however, highly variable. Large differences observed in tocopherol concentrations among soybean genotypes together with the relatively simple biosynthetic pathway involving few genes support the feasibility of selecting for high-tocopherol soybean. Tocopherol concentrations are also highly influenced by environmental factors and field management. Temperature during seed filling and soil moisture appear to be the main factors affecting tocopherol concentrations; other factors such as soil fertility and solar radiation also affect concentrations and composition. Field management decisions including seeding date, row spacing, irrigation, and fertilization also affect tocopherols. Knowledge of factors affecting soybean tocopherols is essential to develop management strategies that will lead to the production of seeds with consistent target concentrations that will meet the needs of the nutraceutical and functional food industries.

  16. Web-based Factors Affecting Online Purchasing Behaviour

    NASA Astrophysics Data System (ADS)

    Ariff, Mohd Shoki Md; Sze Yan, Ng; Zakuan, Norhayati; Zaidi Bahari, Ahamad; Jusoh, Ahmad

    2013-06-01

    The growing use of internet and online purchasing among young consumers in Malaysia provides a huge prospect in e-commerce market, specifically for B2C segment. In this market, if E-marketers know the web-based factors affecting online buyers' behaviour, and the effect of these factors on behaviour of online consumers, then they can develop their marketing strategies to convert potential customers into active one, while retaining existing online customers. Review of previous studies related to the online purchasing behaviour in B2C market has point out that the conceptualization and empirical validation of the online purchasing behaviour of Information and Communication Technology (ICT) literate users, or ICT professional, in Malaysia has not been clearly addressed. This paper focuses on (i) web-based factors which online buyers (ICT professional) keep in mind while shopping online; and (ii) the effect of web-based factors on online purchasing behaviour. Based on the extensive literature review, a conceptual framework of 24 items of five factors was constructed to determine web-based factors affecting online purchasing behaviour of ICT professional. Analysis of data was performed based on the 310 questionnaires, which were collected using a stratified random sampling method, from ICT undergraduate students in a public university in Malaysia. The Exploratory factor analysis performed showed that five factors affecting online purchase behaviour are Information Quality, Fulfilment/Reliability/Customer Service, Website Design, Quick and Details, and Privacy/Security. The result of Multiple Regression Analysis indicated that Information Quality, Quick and Details, and Privacy/Security affect positively online purchase behaviour. The results provide a usable model for measuring web-based factors affecting buyers' online purchase behaviour in B2C market, as well as for online shopping companies to focus on the factors that will increase customers' online purchase.

  17. Accumulation of Heavy Metals in Roadside Soil in Urban Area and the Related Impacting Factors.

    PubMed

    Wang, Meie; Zhang, Haizhen

    2018-05-24

    Heavy metal contamination in roadside soil due to traffic emission has been recognized for a long time. However, seldom has been reported regarding identification of critical factors influencing the accumulation of heavy metals in urban roadside soils due to the frequent disturbances such as the repair of damaged roads and green belt maintanance. Heavy metals in the roadside soils of 45 roads in Xihu district, Hangzhou city were investigated. Results suggested the accumulation of Cu, Pb, Cd, Cr, and Zn in roadside soil was affected by human activity. However, only two sites had Pb and Zn excessing the standards for residential areas, respectively, according to Chinese Environmental Quality Standards for soils. The concentrations of Cu, Pb, Cd, and Zn were significantly and positively correlated to soil pH and organic matter. An insignificant correlation between the age of the roads or vegetation cover types and the concentration of heavy metals was found although they were reported closely relating to the accumulation of heavy metals in roadside soils of highways. The highest Pb, Cd, and Cr taking place in sites with heavy traffic and significant differences in the concentrations of Cu, Pb, Cd, and Zn among the different categories of roads suggested the contribution of traffic intensity. However, it was difficult to establish a quantitative relationship between traffic intensity and the concentrations of heavy metals in the roadside soil. It could be concluded that impaction of traffic emission on the accumulation of heavy metals in roadside soils in urban area was slight and soil properties such as pH and organic matters were critical factors influencing the retention of heavy metals in soils.

  18. Factors Affecting Wound Healing

    PubMed Central

    Guo, S.; DiPietro, L.A.

    2010-01-01

    Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutaneous wound healing and the potential cellular and/or molecular mechanisms involved. The factors discussed include oxygenation, infection, age and sex hormones, stress, diabetes, obesity, medications, alcoholism, smoking, and nutrition. A better understanding of the influence of these factors on repair may lead to therapeutics that improve wound healing and resolve impaired wounds. PMID:20139336

  19. Factors affecting wound healing.

    PubMed

    Guo, S; Dipietro, L A

    2010-03-01

    Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. For a wound to heal successfully, all four phases must occur in the proper sequence and time frame. Many factors can interfere with one or more phases of this process, thus causing improper or impaired wound healing. This article reviews the recent literature on the most significant factors that affect cutaneous wound healing and the potential cellular and/or molecular mechanisms involved. The factors discussed include oxygenation, infection, age and sex hormones, stress, diabetes, obesity, medications, alcoholism, smoking, and nutrition. A better understanding of the influence of these factors on repair may lead to therapeutics that improve wound healing and resolve impaired wounds.

  20. Calculation of Stress Intensity Factors for Interfacial Cracks in Fiber Metal Laminates

    NASA Technical Reports Server (NTRS)

    Wang, John T.

    2009-01-01

    Stress intensity factors for interfacial cracks in Fiber Metal Laminates (FML) are computed by using the displacement ratio method recently developed by Sun and Qian (1997, Int. J. Solids. Struct. 34, 2595-2609). Various FML configurations with single and multiple delaminations subjected to different loading conditions are investigated. The displacement ratio method requires the total energy release rate, bimaterial parameters, and relative crack surface displacements as input. Details of generating the energy release rates, defining bimaterial parameters with anisotropic elasticity, and selecting proper crack surface locations for obtaining relative crack surface displacements are discussed in the paper. Even though the individual energy release rates are nonconvergent, mesh-size-independent stress intensity factors can be obtained. This study also finds that the selection of reference length can affect the magnitudes and the mode mixity angles of the stress intensity factors; thus, it is important to report the reference length used with the calculated stress intensity factors.

  1. Factors Affecting Sign Retroreflectivity : final report.

    DOT National Transportation Integrated Search

    2001-01-01

    This study was undertaken to better understand the factors that may affect road sign retroreflectivity, specifically age and physical orientation. A better understanding of these factors could provide guidance to ODOT in managing its inventory of roa...

  2. Rhizosphere Microbial Community Composition Affects Cadmium and Zinc Uptake by the Metal-Hyperaccumulating Plant Arabidopsis halleri

    PubMed Central

    Muehe, E. Marie; Weigold, Pascal; Adaktylou, Irini J.; Planer-Friedrich, Britta; Kraemer, Ute; Kappler, Andreas

    2015-01-01

    The remediation of metal-contaminated soils by phytoextraction depends on plant growth and plant metal accessibility. Soil microorganisms can affect the accumulation of metals by plants either by directly or indirectly stimulating plant growth and activity or by (im)mobilizing and/or complexing metals. Understanding the intricate interplay of metal-accumulating plants with their rhizosphere microbiome is an important step toward the application and optimization of phytoremediation. We compared the effects of a “native” and a strongly disturbed (gamma-irradiated) soil microbial communities on cadmium and zinc accumulation by the plant Arabidopsis halleri in soil microcosm experiments. A. halleri accumulated 100% more cadmium and 15% more zinc when grown on the untreated than on the gamma-irradiated soil. Gamma irradiation affected neither plant growth nor the 1 M HCl-extractable metal content of the soil. However, it strongly altered the soil microbial community composition and overall cell numbers. Pyrosequencing of 16S rRNA gene amplicons of DNA extracted from rhizosphere samples of A. halleri identified microbial taxa (Lysobacter, Streptomyces, Agromyces, Nitrospira, “Candidatus Chloracidobacterium”) of higher relative sequence abundance in the rhizospheres of A. halleri plants grown on untreated than on gamma-irradiated soil, leading to hypotheses on their potential effect on plant metal uptake. However, further experimental evidence is required, and wherefore we discuss different mechanisms of interaction of A. halleri with its rhizosphere microbiome that might have directly or indirectly affected plant metal accumulation. Deciphering the complex interactions between A. halleri and individual microbial taxa will help to further develop soil metal phytoextraction as an efficient and sustainable remediation strategy. PMID:25595759

  3. Age Learning Factors Affecting Pilot Education.

    ERIC Educational Resources Information Center

    Torbert, Brison

    This document, intended for pilot education and flight safety specialists, consists chiefly of a review of the literature on physiological factors that affect pilot education and an examination of environmental factors that should be scrutinized in order to improve the effectiveness of aviation learning facilities. The physiological factors…

  4. Serpentine soils affect heavy metal tolerance but not genetic diversity in a common Mediterranean ant.

    PubMed

    Frizzi, Filippo; Masoni, Alberto; Çelikkol, Mine; Palchetti, Enrico; Ciofi, Claudio; Chelazzi, Guido; Santini, Giacomo

    2017-08-01

    Natural habitats with serpentine soils are rich in heavy metal ions, which may significantly affect ecological communities. Exposure to metal pollutants results, for instance, in a reduction of population genetic diversity and a diffused higher tolerance towards heavy metals. In this study, we investigated whether chronic exposure to metals in serpentine soils affect accumulation patterns, tolerance towards metal pollutants, and genetic diversity in ants. In particular, we studied colonies of the common Mediterranean ant, Crematogaster scutellaris, along a contamination gradient consisting of two differently contaminated forests and a reference soil with no geogenic contamination. We first evaluated the metal content in both soil and ants' body. Then, we tested for tolerance towards metal pollutants by evaluating the mortality of ants fed with nickel (Ni) solutions of increasing concentrations. Finally, differences in genetic diversity among ants from different areas were assessed using eight microsatellite loci. Interestingly, a higher tolerance to nickel solutions was found in ants sampled in sites with intermediate levels of heavy metals. This may occur, because ants inhabiting strongly contaminated areas tend to accumulate higher amounts of contaminants. Additional ingestion of toxicants beyond the saturation threshold would lead to death. There was no difference in the genetic diversity among ant colonies sampled in different sites. This was probably the result of queen mediated gene flow during nuptial flights across uncontaminated and contaminated areas of limited geographical extent. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Interrelationships of metal transfer factor under wastewater reuse and soil pollution.

    PubMed

    Papaioannou, D; Kalavrouziotis, I K; Koukoulakis, P H; Papadopoulos, F; Psoma, P

    2018-06-15

    The transfer of heavy metals under soil pollution wastewater reuse was studied in a Greenhouse experiment using a randomized block design, including 6 treatments of heavy metals mixtures composed of Zn, Mn, Cd, Co, Cu, Cr, Ni, and Pb, where each metal was taking part in the mixture with 0, 10, 20, 30, 40, 50 mg/kg respectively, in four replications. The Beta vulgaris L (beet) was used as a test plant. It was found that the metal transfer factors were statistically significantly related to the: (i) DTPA extractable soil metals, (ii) the soil pollution level as assessed by the pollution indices, (iii) the soil pH, (iv) the beet dry matter yield and (v) the interactions between the heavy metals in the soil. It was concluded that the Transfer Factor is subjected to multifactor effects and its real nature is complex, and there is a strong need for further study for the understanding of its role in metal-plant relationships. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Environmental Factors Affecting Preschoolers' Motor Development

    ERIC Educational Resources Information Center

    Venetsanou, Fotini; Kambas, Antonis

    2010-01-01

    The process of development occurs according to the pattern established by the genetic potential and also by the influence of environmental factors. The aim of the present study was to focus on the main environmental factors affecting motor development. The review of the literature revealed that family features, such as socioeconomic status,…

  7. Factors affecting the mobilization of DOC and metals in a peat soil under a warmer scenario

    NASA Astrophysics Data System (ADS)

    Carrera, Noela; Barreal, María. Esther; Briones, María. Jesús I.

    2010-05-01

    Most climate change models predict an increase of temperature of 3-5°C in Southern Europe by the end of this century (IPCC 2007). However, changes in summer precipitations are more uncertain, and although a decrease in rainfall inputs is forecasted by most models, the magnitude of this effect has not been assessed properly (Rowell & Jones 2006). Peatland areas are very sensitive to climate change. In Galicia they survive in upland areas where cold temperatures and continuous moisture supply allow their presence. Besides abiotic factors, alterations in soil fauna activities can also affect peat turnover. Among them, enchytraeids are usually the most numerous invertebrate group in these systems and both temperature and moisture content regulate their abundances and vertical distribution. Previous studies have demonstrated that changes in their populations associated to increasing temperatures can significantly affect metal mobilization, namely iron and aluminium, together with an important decline in the acidity of the soil solution, which possibly eliminates one of the critical mechanisms restricting DOC release (Carrera et al., 2009). In this study we investigated whether changes in water content of the peat soil and soil invertebrate activities associated to increasing temperatures could alter the mobilization rates of Fe and Al and in turn, DOC. 72 undisturbed soil cores (6 cm diameter x 10 cm deep) with their associated vegetation were taken from a blanket bog in Galicia (NW Spain). Back at the laboratory they were sliced horizontally into two layers, (0-5cm and 5-10cm) which were defaunated by means of a wet extraction. Thereafter, the two soil layers derived from the same core were introduced in each microcosm by placing them in their original position but separated by a 1 mm nylon mesh to allow the vertical movements of the organisms. Half of the experimental units were adjusted to the used moisture values observed in the field (80% SWC, H1), whereas in the

  8. Nutritional Factors Affecting Adult Neurogenesis and Cognitive Function.

    PubMed

    Poulose, Shibu M; Miller, Marshall G; Scott, Tammy; Shukitt-Hale, Barbara

    2017-11-01

    Adult neurogenesis, a complex process by which stem cells in the hippocampal brain region differentiate and proliferate into new neurons and other resident brain cells, is known to be affected by many intrinsic and extrinsic factors, including diet. Neurogenesis plays a critical role in neural plasticity, brain homeostasis, and maintenance in the central nervous system and is a crucial factor in preserving the cognitive function and repair of damaged brain cells affected by aging and brain disorders. Intrinsic factors such as aging, neuroinflammation, oxidative stress, and brain injury, as well as lifestyle factors such as high-fat and high-sugar diets and alcohol and opioid addiction, negatively affect adult neurogenesis. Conversely, many dietary components such as curcumin, resveratrol, blueberry polyphenols, sulforaphane, salvionic acid, polyunsaturated fatty acids (PUFAs), and diets enriched with polyphenols and PUFAs, as well as caloric restriction, physical exercise, and learning, have been shown to induce neurogenesis in adult brains. Although many of the underlying mechanisms by which nutrients and dietary factors affect adult neurogenesis have yet to be determined, nutritional approaches provide promising prospects to stimulate adult neurogenesis and combat neurodegenerative diseases and cognitive decline. In this review, we summarize the evidence supporting the role of nutritional factors in modifying adult neurogenesis and their potential to preserve cognitive function during aging. © 2017 American Society for Nutrition.

  9. Plant water relations as affected by heavy metal stress: A review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barcelo, J.; Poschenrieder, C.

    1990-01-01

    Metal toxicity causes multiple direct and indirect effects in plants which concern practically all physiological functions. In this review the effects of excess heavy metals and aluminum on those functions which will alter plant water relations are considered. After a brief comment on the metal effects in cell walls and plasma-lemma, and their consequences for cell expansion growth, the influences of high meal availability on the factors which regulate water entry and water exit in plants are considered. Emphasis is placed on the importance of distinguishing between low water availability in mine and serpentine soils and toxicity effects in plantsmore » which may impair the ability of a plant to regulate water uptake. Examples on water relations of both plants grown on metalliferous soil and hydroponics are presented, and the effects of metal toxicity on root growth, water transport and transpiration are considered. It is concluded that future research has to focus on the mechanisms of metal-induced inhibition of both root elongation and morphogenetic processes within roots. In order to understand the relation between metal tolerance and drought resistance better, further studies into metal tolerance mechanisms at the cell wall, membrane and vacuolar level, as well as into the mechanisms of drought resistance of plants adapted to metalliferous soils are required. 135 refs., 7 figs., 6 tabs.« less

  10. Causal inference between bioavailability of heavy metals and environmental factors in a large-scale region.

    PubMed

    Liu, Yuqiong; Du, Qingyun; Wang, Qi; Yu, Huanyun; Liu, Jianfeng; Tian, Yu; Chang, Chunying; Lei, Jing

    2017-07-01

    The causation between bioavailability of heavy metals and environmental factors are generally obtained from field experiments at local scales at present, and lack sufficient evidence from large scales. However, inferring causation between bioavailability of heavy metals and environmental factors across large-scale regions is challenging. Because the conventional correlation-based approaches used for causation assessments across large-scale regions, at the expense of actual causation, can result in spurious insights. In this study, a general approach framework, Intervention calculus when the directed acyclic graph (DAG) is absent (IDA) combined with the backdoor criterion (BC), was introduced to identify causation between the bioavailability of heavy metals and the potential environmental factors across large-scale regions. We take the Pearl River Delta (PRD) in China as a case study. The causal structures and effects were identified based on the concentrations of heavy metals (Zn, As, Cu, Hg, Pb, Cr, Ni and Cd) in soil (0-20 cm depth) and vegetable (lettuce) and 40 environmental factors (soil properties, extractable heavy metals and weathering indices) in 94 samples across the PRD. Results show that the bioavailability of heavy metals (Cd, Zn, Cr, Ni and As) was causally influenced by soil properties and soil weathering factors, whereas no causal factor impacted the bioavailability of Cu, Hg and Pb. No latent factor was found between the bioavailability of heavy metals and environmental factors. The causation between the bioavailability of heavy metals and environmental factors at field experiments is consistent with that on a large scale. The IDA combined with the BC provides a powerful tool to identify causation between the bioavailability of heavy metals and environmental factors across large-scale regions. Causal inference in a large system with the dynamic changes has great implications for system-based risk management. Copyright © 2017 Elsevier Ltd. All

  11. Metal toxicity differently affects the Iris pseudacorus-arbuscular mycorrhiza fungi symbiosis in terrestrial and semi-aquatic habitats.

    PubMed

    Wężowicz, K; Turnau, K; Anielska, T; Zhebrak, I; Gołuszka, K; Błaszkowski, J; Rozpądek, P

    2015-12-01

    Phytoremediation offers an environmental friendly alternative to conventional cleanup techniques. In this study, mycorrhizal fungi isolated from the roots of Mentha longifolia grown in the basin of the Centuria River (S Poland) were used. Iris pseudacorus was grown in substratum from an industrial waste, enriched in Pb, Fe, Zn, and Cd in a terrestrial and water-logged habitat. Plant yield and photosynthetic performance was the highest in the aquatic environment; however, the presence of toxic metals (TM) negatively affected photosystem II (PSII) photochemistry as shown by the JIP test. Fungi colonization and Cd accumulation within plant tissues was decreased. In the terrestrial habitat, neither arbuscular mycorrhizal fungi (AMF) nor metal toxicity affected plant growth, although metal uptake, Cd in particular, as well as photosynthesis were affected. Inoculated plants accumulated significantly more Cd, and photosynthesis was downregulated. The results presented in this study clearly indicate that the I. pseudacorus-AMF symbiosis adapts itself to the presence of toxic metals in the environment, optimizing resource supply, energy fluxes, and possibly stress tolerance mechanisms. Plant/AMF consortia grown in terrestrial and water-logged habitats utilize different strategies to cope with metal toxicity. The use of AMF in improving the phytoremediation potential of I. pseudacorus needs, however, further research.

  12. Factors affecting dignity of patients with multiple sclerosis.

    PubMed

    Sharifi, Simin; Borhani, Fariba; Abbaszadeh, Abbas

    2016-12-01

    MS is one of the most common chronic diseases of the nervous system. Apart from disease progression, other complications such as unemployment, separation and divorce could potentially threat patients' dignity. Most of the previous studies have been done of maintaining patients' dignity in interaction with healthcare team, but studies on affecting factors of dignity in chronic patients in the society and in interaction with usual people are scarce. We aimed to investigate factors affecting dignity of Iranian patients with MS in daily living and in interaction of them with the society. In this qualitative study, 13 patients with multiple sclerosis were chosen by purposive sampling and semi-structured interviews were conducted until data saturation. The study was done in Tehran, the capital city of Iran. Factors affecting dignity were classified as 'personal factors' and 'social factors'. Personal factors consist of the following subcategories: patients' communication with self, patients' knowledge, patients' values and beliefs and patients' resources. Social factors include others' communication with patients, social knowledge, social values and beliefs and social resources. Multiple personal and social factors interfere in perceived patient dignity. In fact, interaction between personal and social factors can be influential in final perceived dignity. By focusing on whole aspects of the patients' lives, we can identify dignity-promoting or dignity-threatening factors and help patients maintain their dignity by taking appropriate measures for moderating threatening factors and improving dignity enhancing ones. © 2016 Nordic College of Caring Science.

  13. Evaluation of the factors governing metal biosorption and metal toxicity in acidic soil isolates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pradhan, A.A.

    1992-06-09

    This research project was designed to determine the feasibility of microbial biosorption processes for removing metal ions from aqueous systems. A culture of acidic soil actinomycetes, grown in an aerobic environment in a completely mixed, semibatch culture reactor, was used for the study. The experiments were based on removal of copper and lead from test solutions. The anionic systems tested were nitrate, sulfate, and chloride. To determine the factors influencing biosorption and to characterize metal uptake by cellular and extracellular components of the microbial system, a dialysis testing procedure was developed. The effectiveness of biosorption was influenced by pH, initialmore » concentration of metals, type of anionic system, and organic content of the system. respirometric runs were carried out to identify potential inhibitory effects of metal accumulation on microbial activities. In general, metal accumulation resulted in a decrease in the microbial oxygen uptake rate. Also, a lag phase was observed before the onset of the respiratory activity particularly at concentrations of copper and lead greater than 100 ppM.« less

  14. To what extent do structural changes in catalytic metal sites affect enzyme function?

    PubMed

    Valasatava, Yana; Rosato, Antonio; Furnham, Nicholas; Thornton, Janet M; Andreini, Claudia

    2018-02-01

    About half of known enzymatic reactions involve metals. Enzymes belonging to the same superfamily often evolve to catalyze different reactions on the same structural scaffold. The work presented here investigates how functional differentiation, within superfamilies that contain metalloenzymes, relates to structural changes at the catalytic metal site. In general, when the catalytic metal site is unchanged across the enzymes of a superfamily, the functional differentiation within the superfamily tends to be low and the mechanism conserved. Conversely, all types of structural changes in the metal binding site are observed for superfamilies with high functional differentiation. Overall, the catalytic role of the metal ions appears to be one of the most conserved features of the enzyme mechanism within metalloenzyme superfamilies. In particular, when the catalytic role of the metal ion does not involve a redox reaction (i.e. there is no exchange of electrons with the substrate), this role is almost always maintained even when the site undergoes significant structural changes. In these enzymes, functional diversification is most often associated with modifications in the surrounding protein matrix, which has changed so much that the enzyme chemistry is significantly altered. On the other hand, in more than 50% of the examples where the metal has a redox role in catalysis, changes at the metal site modify its catalytic role. Further, we find that there are no examples in our dataset where metal sites with a redox role are lost during evolution. In this paper we investigate how functional diversity within superfamilies of metalloenzymes relates to structural changes at the catalytic metal site. Evolution tends to strictly conserve the metal site. When changes occur, they do not modify the catalytic role of non-redox metals whereas they affect the role of redox-active metals. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Gender is a significant factor for failure of metal-on-metal total hip arthroplasty.

    PubMed

    Latteier, Michael J; Berend, Keith R; Lombardi, Adolph V; Ajluni, Andrew F; Seng, Brian E; Adams, Joanne B

    2011-09-01

    Metal-on-metal (MoM) articulations offers low wear, larger head size, and increased stability. Reports of early failure are troubling and include failure of ingrowth and metal articulation problems such as metallosis, hypersensitivity, pseudotumor, and unexplained pain. This study investigates the survivorship of modern MoM articulations by gender. We reviewed 1589 primary MoM THA in 1363 patients, with minimum 2-year follow-up for 1212 hips. Follow-up averaged 60 months. There were 643 female patients and 719 male patients. The incidence of cup revision was significantly higher in women than in men (8.2% vs 2.7%; P = .0000), as was incidence of aseptic loosening (4.3% vs 1.1%; P = .0006), and failure for metal-bearing complications (2.2% vs 0.6%; P = .0126). There appear to be gender factors influencing the success of MoM THA, which may include hormonal, anatomic, or functional differences. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Factors affecting nucleolytic efficiency of some ternary metal complexes with DNA binding and recognition domains. Crystal and molecular structure of Zn(phen)(edda).

    PubMed

    Seng, Hoi-Ling; Ong, Han-Kiat Alan; Rahman, Raja Noor Zaliha Raja Abd; Yamin, Bohari M; Tiekink, Edward R T; Tan, Kong Wai; Maah, Mohd Jamil; Caracelli, Ignez; Ng, Chew Hee

    2008-11-01

    The binding selectivity of the M(phen)(edda) (M=Cu, Co, Ni, Zn; phen=1,10-phenanthroline, edda=ethylenediaminediacetic acid) complexes towards ds(CG)(6), ds(AT)(6) and ds(CGCGAATTCGCG) B-form oligonucleotide duplexes were studied by CD spectroscopy and molecular modeling. The binding mode is intercalation and there is selectivity towards AT-sequence and stacking preference for A/A parallel or diagonal adjacent base steps in their intercalation. The nucleolytic properties of these complexes were investigated and the factors affecting the extent of cleavage were determined to be: concentration of complex, the nature of metal(II) ion, type of buffer, pH of buffer, incubation time, incubation temperature, and the presence of hydrogen peroxide or ascorbic acid as exogenous reagents. The fluorescence property of these complexes and its origin were also investigated. The crystal structure of the Zn(phen)(edda) complex is reported in which the zinc atom displays a distorted trans-N(4)O(2) octahedral geometry; the crystal packing features double layers of complex molecules held together by extensive hydrogen bonding that inter-digitate with adjacent double layers via pi...pi interactions between 1,10-phenanthroline residues. The structure is compared with that of the recently described copper(II) analogue and, with the latter, included in molecular modeling.

  17. Strain intensity factor approach for predicting the strength of continuously reinforced metal matrix composites

    NASA Technical Reports Server (NTRS)

    Poe, C. C., Jr.

    1988-01-01

    A method was previously developed to predict the fracture toughness (stress intensity factor at failure) of composites in terms of the elastic constants and the tensile failing strain of the fibers. The method was applied to boron/aluminum composites made with various proportions of 0 to + or - 45 deg plies. Predicted values of fracture toughness were in gross error because widespread yielding of the aluminum matrix made the compliance very nonlinear. An alternate method was developed to predict the strain intensity factor at failure rather than the stress intensity factor because the singular strain field was not affected by yielding as much as the stress field. Strengths of specimens containing crack-like slits were calculated from predicted failing strains using uniaxial stress-strain curves. Predicted strengths were in good agreement with experimental values, even for the very nonlinear laminates that contained only + or - 45 deg plies. This approach should be valid for other metal matrix composites that have continuous fibers.

  18. Economic and Cultural Factors Affecting University Excellence

    ERIC Educational Resources Information Center

    Jabnoun, Naceur

    2009-01-01

    Purpose: The ranking of top universities in the world has generated increased interest in the factors that enhance university performance. The purpose of this paper is to identify economic and cultural factors that affect the number of top ranking universities in each country. Design/methodology/approach: This paper first identifies the number of…

  19. ENVIRONMENTAL FACTORS AFFECTING BREAST CANCER SUSCEPTIBILITY

    EPA Science Inventory

    Environmental Factors Affecting Breast Cancer Susceptibility
    Suzanne. E. Fenton
    US EPA, ORD, MD-67 NHEERL, Reproductive Toxicology Division, Research Triangle Park, NC 27711.

    Breast cancer is still the most common malignancy afflicting women in the Western world. Alt...

  20. Factors Affecting Radon Concentration in Houses

    NASA Astrophysics Data System (ADS)

    Al-Sharif, Abdel-Latif; Abdelrahman, Y. S.

    2001-03-01

    The dangers to the human health upon exposure to radon and its daughter products is the main motivation behind the vast number of studies performed to find the concentration of radon in our living environment, including our houses. The presence of radon and its daughter products in houses are due to various sources including building materials and the soil under the houses. Many factors affect radon concentration in our houses, the elevation above ground level,ventilation, building materials and room usage being among these factors. In our paper, we discuss the effect of elevation above ground level, room usage and ventilation on the Radon concentration in houses. The faculty residences of the Mu'tah University (Jordan) were chosen in our study. Our results showed that the concentration of radon decreases with elevation. Ventilation rate was also found to affect radon concentration, where low concentrations observed for areas with good ventilation.

  1. Factors affecting caregivers' ability to make environmental modifications.

    PubMed

    Messecar, D C

    2000-12-01

    This study explored factors that family caregivers described as affecting their ability to use environmental modifications. Intensive interviews and participant observation were used to collect detailed data from 24 primary family caregivers. Several factors that affect the caregivers' ability to implement modification strategies were identified in the analysis. These factors included attributes of the elderly individual, attributes of the modification, quality of the caregiver-elderly relationship, caregivers' skills, personal resources of the caregiver, and the informal and formal supports available. Of these factors, the most important were the salient skills that caregivers need to implement environmental modifications. These findings point to the importance of caregivers receiving skills training in this important dimension of caregiving. Intervention should be based on a collaborative approach that ensures the caregiver and care receiver's needs and preferences are respected.

  2. Strain intensity factor approach for predicting the strength of continuously reinforced metal matrix composites

    NASA Technical Reports Server (NTRS)

    Poe, Clarence C., Jr.

    1989-01-01

    A method was previously developed to predict the fracture toughness (stress intensity factor at failure) of composites in terms of the elastic constants and the tensile failing strain of the fibers. The method was applied to boron/aluminum composites made with various proportions of 0 deg and +/- 45 deg plies. Predicted values of fracture toughness were in gross error because widespread yielding of the aluminum matrix made the compliance very nonlinear. An alternate method was develolped to predict the strain intensity factor at failure rather than the stress intensity factor because the singular strain field was not affected by yielding as much as the stress field. Far-field strains at failure were calculated from the strain intensity factor, and then strengths were calculated from the far-field strains using uniaxial stress-strain curves. The predicted strengths were in good agreement with experimental values, even for the very nonlinear laminates that contained only +/- 45 deg plies. This approach should be valid for other metal matrix composites that have continuous fibers.

  3. Evaluation of the Possible Sources and Controlling Factors of Toxic Metals/Metalloids in the Florida Everglades and Their Potential Risk of Exposure.

    PubMed

    Li, Yanbin; Duan, Zhiwei; Liu, Guangliang; Kalla, Peter; Scheidt, Daniel; Cai, Yong

    2015-08-18

    The Florida Everglades is an environmentally sensitive wetland ecosystem with a number of threatened and endangered fauna species susceptible to the deterioration of water quality. Several potential toxic metal sources exist in the Everglades, including farming, atmospheric deposition, and human activities in urban areas, causing concerns of potential metal exposure risks. However, little is known about the pollution status of toxic metals/metalloids of potential concern, except for Hg. In this study, eight toxic metals/metalloids (Cd, Cr, Pb, Ni, Cu, Zn, As, and Hg) in Everglades soils were investigated in both dry and wet seasons. Pb, Cr, As, Cu, Cd, and Ni were identified to be above Florida SQGs (sediment quality guidelines) at a number of sampling sites, particularly Pb, which had a level of potential risk to organisms similar to that of Hg. In addition, a method was developed for quantitative source identification and controlling factor elucidation of toxic metals/metalloids by introducing an index, enrichment factor (EF), in the conventional multiple regression analysis. EFs represent the effects of anthropogenic sources on metals/metalloids in soils. Multiple regression analysis showed that Cr and Ni were mainly controlled by anthropogenic loading, whereas soil characteristics, in particular natural organic matter (NOM), played a more important role for Hg, As, Cd, and Zn. NOM may control the distribution of these toxic metals/metalloids by affecting their mobility in soils. For Cu and Pb, the effects of EFs and environmental factors are comparable, suggesting combined effects of loading and soil characteristics. This study is the first comprehensive research with a vast amount of sampling sites on the distribution and potential risks of toxic metals/metalloids in the Everglades. The finding suggests that in addition to Hg other metals/metalloids could also potentially be an environmental problem in this wetland ecosystem.

  4. Distributions and contamination assessment of heavy metals in the surface sediments of western Laizhou Bay: Implications for the sources and influencing factors.

    PubMed

    Zhang, Pan; Hu, Rijun; Zhu, Longhai; Wang, Peng; Yin, Dongxiao; Zhang, Lianjie

    2017-06-15

    Heavy metals (Cu, Pb, Cr, Cd and As) contents in surface sediments from western Laizhou Bay were analysed to evaluate the spatial distribution pattern and their contamination level. As was mainly concentrated in the coastal area near the estuaries and the other metals were mainly concentrated in the central part of the study area. The heavy metals were present at unpolluted levels overall evaluated by the sediment quality guidelines and geoaccumulation index. Principal component analysis suggest that Cu, Pb and Cd were mainly sourced from natural processes and As was mainly derived from anthropogenic inputs. Meanwhile, Cr originated from both natural processes and anthropogenic contributions. Tidal currents, sediments and human activities were important factors affecting the distribution of heavy metals. The heavy metal environment was divided into four subareas to provide a reference for understanding the distribution and pollution of heavy metals in the estuary-bay system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Nutrients affecting gastric barrier.

    PubMed

    Gasbarrini, Antonio; D'Aversa, Francesca; Di Rienzo, Teresa; Franceschi, Francesco

    2014-01-01

    The gastric barrier could be considered an active tissue involved in many synthetic and metabolic functions, as the immunological defense, by activating mucosal immune system. Barrier integrity results from a balance between protective and aggressive endogenous factors and from their interaction with exogenous factors (steroidal or nonsteroidal anti-inflammatory drugs, dietary nitrates, nitrites and/or NaCl, stress, Helicobacter pylori infection, food allergens and contaminants, metals, chemicals, radiation, smoking and alcohol intake). Nutrients represent the most important exogenous factors affecting gastric barrier because of the impact on people's everyday life. We report evidence from the literature about nutrients affecting gastric barrier and we investigate the possible effect that nutrients can play to determining or maintaining a gastric barrier dysfunction. © 2014 S. Karger AG, Basel.

  6. Which factors affect software projects maintenance cost more?

    PubMed

    Dehaghani, Sayed Mehdi Hejazi; Hajrahimi, Nafiseh

    2013-03-01

    The software industry has had significant progress in recent years. The entire life of software includes two phases: production and maintenance. Software maintenance cost is increasingly growing and estimates showed that about 90% of software life cost is related to its maintenance phase. Extraction and considering the factors affecting the software maintenance cost help to estimate the cost and reduce it by controlling the factors. In this study, the factors affecting software maintenance cost were determined then were ranked based on their priority and after that effective ways to reduce the maintenance costs were presented. This paper is a research study. 15 software related to health care centers information systems in Isfahan University of Medical Sciences and hospitals function were studied in the years 2010 to 2011. Among Medical software maintenance team members, 40 were selected as sample. After interviews with experts in this field, factors affecting maintenance cost were determined. In order to prioritize the factors derived by AHP, at first, measurement criteria (factors found) were appointed by members of the maintenance team and eventually were prioritized with the help of EC software. Based on the results of this study, 32 factors were obtained which were classified in six groups. "Project" was ranked the most effective feature in maintenance cost with the highest priority. By taking into account some major elements like careful feasibility of IT projects, full documentation and accompany the designers in the maintenance phase good results can be achieved to reduce maintenance costs and increase longevity of the software.

  7. Proposed industrial recovered materials utilization targets for the metals and metal products industry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1979-05-01

    Set targets for increased utilization of energy-saving recovered materials in the metals and metal products industries (ferrous, aluminium, copper, zinc, and lead) are discussed. Data preparation and methodology development and analysis of the technological and economic factors in order to prepare draft targets for the use of recovered materials are covered. Chapter 2 provides an introductory discussion of the factors that affect the recovery and reuse of secondary materials and the competition between the primary and secondary metals industries. Chapter 3 presents general profiles for the major industrial segments comprising SIC 33, including industry structure, process technology, materials and recyclingmore » flow, and future trends for the 5 industries: ferrous, aluminium, copper, zinc, and lead. Chapter 4 presents the evaluation of recycling targets for those industries. (MCW)« less

  8. Ecological risk assessment of boreal sediments affected by metal mining: Metal geochemistry, seasonality, and comparison of several risk assessment methods.

    PubMed

    Väänänen, Kristiina; Kauppila, Tommi; Mäkinen, Jari; Leppänen, Matti T; Lyytikäinen, Merja; Akkanen, Jarkko

    2016-10-01

    The mining industry is a common source of environmental metal emissions, which cause long-lasting effects in aquatic ecosystems. Metal risk assessment is challenging due to variations in metal distribution, speciation, and bioavailability. Therefore, seasonal effects must be better understood, especially in boreal regions in which seasonal changes are large. We sampled 4 Finnish lakes and sediments affected by mining for metals and geochemical characteristics in autumn and late winter, to evaluate seasonal changes in metal behavior, the importance of seasonality in risk assessment, and the sensitivity and suitability of different risk assessment methods. We compared metal concentrations in sediment, overlying water, and porewater against environmental quality guidelines (EQGs). We also evaluated the toxicity of metal mixtures using simultaneously extracted metals and an acid volatile sulfides (SEM-AVS) approach together with water quality criteria (US Environmental Protection Agency equilibrium partitioning benchmarks). Finally, site-specific risks for 3 metals (Cu, Ni, Zn) were assessed using 2 biotic ligand models (BLMs). The metal concentrations in the impacted lakes were elevated. During winter stratification, the hypolimnetic O2 saturation levels were low (<6%) and the pH was acidic (3.5-6.5); however, abundant O2 (>89%) and neutral pH (6.1-7.5) were found after the autumnal water overturn. Guidelines were the most conservative benchmark for showing an increased risk of toxicity in the all of the lakes. The situation remained stable between seasons. On the other hand, SEM-AVS, equilibrium partition sediment benchmarks (ESBs), and BLMs provided a clearer distinction between lakes and revealed a seasonal variation in risk among some of the lakes, which evidenced a higher risk during late winter. If a sediment risk assessment is based on the situation in the autumn, the overall risk may be underestimated. It is advisable to carry out sampling and risk assessment

  9. Influence of the soil sealing on the geoaccumulation index of heavy metals and various pollution factors.

    PubMed

    Charzyński, Przemysław; Plak, Andrzej; Hanaka, Agnieszka

    2017-02-01

    Soil sealing belongs to the most destructive and damaging processes to the soil environment. Soil sealing interrupts or greatly restricts the exchange of matter and energy between the biosphere, hydrosphere, and atmosphere and the soil environment. The aim of this study was to compare the content of heavy metals (Cd, Cr, Cu, Hg, Fe, Ni, Pb, Zn) of Ekranic Technosols by applying indicators such as geoaccumulation index (I geo ), enrichment factor (EF), and pollution load index (PLI), which allowed to determine quantitatively the impact of the soil sealing degree on the content of heavy metals and to distinguish natural from anthropogenic sources of origin of heavy metals. In general, 42 soils from different parts of the city of Toruń (NW Poland) were sampled and divided into three groups according to the degree of soil sealing: completely sealed with asphalt or concrete (A), semi-permeable (partially sealed with cobblestones and concrete paving slabs (B)), and reference (non-sealed) (C). The results indicate that the artificial sealing in urban areas slightly affects the content of heavy metals in soils. However, based on PLI, I geo , and EF, it was found that the sealing has influence on soil properties and unsealed soil is the most exposed to the accumulation of pollutants.

  10. Preslaughter factors affecting poultry meat quality chapter 2.

    USDA-ARS?s Scientific Manuscript database

    Poultry meat quality is affected by numerous antemortem factors, in particular those occurring during the last 24 hours that the bird is alive. These short term factors influence carcass yield (live shrink), carcass defects (bruising, broken/dislocated bones), carcass microbiological contamination, ...

  11. Approaches for enhanced phytoextraction of heavy metals.

    PubMed

    Bhargava, Atul; Carmona, Francisco F; Bhargava, Meenakshi; Srivastava, Shilpi

    2012-08-30

    The contamination of the environment with toxic metals has become a worldwide problem. Metal toxicity affects crop yields, soil biomass and fertility. Soils polluted with heavy metals pose a serious health hazard to humans as well as plants and animals, and often requires soil remediation practices. Phytoextraction refers to the uptake of contaminants from soil or water by plant roots and their translocation to any harvestable plant part. Phytoextraction has the potential to remove contaminants and promote long-term cleanup of soil or wastewater. The success of phytoextraction as a potential environmental cleanup technology depends on factors like metal availability for uptake, as well as plants ability to absorb and accumulate metals in aerial parts. Efforts are ongoing to understand the genetics and biochemistry of metal uptake, transport and storage in hyperaccumulator plants so as to be able to develop transgenic plants with improved phytoremediation capability. Many plant species are being investigated to determine their usefulness for phytoextraction, especially high biomass crops. The present review aims to give an updated version of information available with respect to metal tolerance and accumulation mechanisms in plants, as well as on the environmental and genetic factors affecting heavy metal uptake. The genetic tools of classical breeding and genetic engineering have opened the door to creation of 'remediation' cultivars. An overview is presented on the possible strategies for developing novel genotypes with increased metal accumulation and tolerance to toxicity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Metals and lipid oxidation. Contemporary issues.

    PubMed

    Schaich, K M

    1992-03-01

    Lipid oxidation is now recognized to be a critically important reaction in physiological and toxicological processes as well as in food products. This provides compelling reasons to understand what causes lipid oxidation in order to be able to prevent or control the reactions. Redox-active metals are major factors catalyzing lipid oxidation in biological systems. Classical mechanisms of direct electron transfer to double bonds by higher valence metals and of reduction of hydroperoxides by lower valence metals do not always account for patterns of metal catalysis of lipid oxidation in multiphasic or compartmentalized biological systems. To explain why oxidation kinetics, mechanisms, and products in molecular environments which are both chemically and physically complex often do not follow classical patterns predicted by model system studies, increased consideration must be given to five contemporary issues regarding metal catalysis of lipid oxidation: hypervalent non-heme iron or iron-oxygen complexes, heme catalysis mechanism(s), compartmentalization of reactions and lipid phase reactions of metals, effects of metals on product mixes, and factors affecting the mode of metal catalytic action.

  13. FACTORS ADVERSELY AFFECTING AMPHIBIAN POPULATIONS IN THE US

    EPA Science Inventory

    Factors known or suspected to be adversely affecting native amphibian populations in the US were identified using information from species accounts written in a standardized format by multiple authors in a forthcoming book. Specific adverse factors were identified for 53 (58%) of...

  14. Factors affecting radiographers' organizational commitment.

    PubMed

    Akroyd, Duane; Jackowski, Melissa B; Legg, Jeffrey S

    2007-01-01

    A variety of factors influence employees' attitudes toward their workplace and commitment to the organization that employs them. However, these factors have not been well documented among radiologic technologists. To determine the predictive ability of selected organizational, leadership, work-role and demographic variables on organizational commitment for a national sample of radiographers. Three thousand radiographers registered by the American Registry of Radiologic Technologists working full time in clinical settings were surveyed by mail regarding their commitment to their employers, leadership within the organization that employs them, employer support and demographic information. Overall, radiographers were found to have only a moderate level of commitment to their employers. Among the factors that significantly affected commitment were the radiographer's educational level, perceived level of organizational support, role clarity and organizational leadership. The results of this study could provide managers and supervisors with insights on how to empower and challenge radiographers and offer opportunities that will enhance radiographers' commitment to the organization, thus reducing costly turnover and improving employee performance.

  15. Factors Affecting Faculty Web Portal Usability

    ERIC Educational Resources Information Center

    Bringula, Rex P.; Basa, Roselle S.

    2011-01-01

    The study investigated the factors that might significantly affect web portal usability. Results of the study were intended to serve as inputs for faculty web portal development of the University of the East-Manila. Descriptive statistics utilized questionnaire data from 82 faculty members. The data showed that most of the respondents were…

  16. Quantification of Stereochemical Communication in Metal-Organic Assemblies.

    PubMed

    Castilla, Ana M; Miller, Mark A; Nitschke, Jonathan R; Smulders, Maarten M J

    2016-08-26

    The derivation and application of a statistical mechanical model to quantify stereochemical communication in metal-organic assemblies is reported. The factors affecting the stereochemical communication within and between the metal stereocenters of the assemblies were experimentally studied by optical spectroscopy and analyzed in terms of a free energy penalty per "incorrect" amine enantiomer incorporated, and a free energy of coupling between stereocenters. These intra- and inter-vertex coupling constants are used to track the degree of stereochemical communication across a range of metal-organic assemblies (employing different ligands, peripheral amines, and metals); temperature-dependent equilibria between diastereomeric cages are also quantified. The model thus provides a unified understanding of the factors that shape the chirotopic void spaces enclosed by metal-organic container molecules.

  17. Low Calorie Diet Affects Aging-Related Factors

    MedlinePlus

    ... Research News From NIH Low Calorie Diet Affects Aging-Related Factors Past Issues / Summer 2006 Table of ... project sponsored by the NIH's National Institute on Aging (NIA) to learn more about the effects of ...

  18. ASRDI oxygen technology survey, Volume 7: Characteristics of metals that influence system safety

    NASA Technical Reports Server (NTRS)

    Pelouch, J. J., Jr.

    1974-01-01

    A literature survey and analysis of the material and process factors affecting the safety of metals in oxygen systems is presented. In addition, the practices of those who specify, build, or use oxygen systems relative to the previous is summarized. Alloys based on iron, copper, nickel, and aluminum were investigated representing the bulk of metals found in oxygen systems. Safety-related characteristics of other miscellaneous metals are summarized. It was found that factors affecting the safety of metals in oxygen systems exit in all phases of the evolutionary process, from smelting and mill techniques through end-production fabrication. The safety of a given metal in an oxygen system was determined to be influenced by the particular service requirement. The metal characteristics should favorably influence fulfillment of these requirements. Thus, no singular metal or alloy could be classified as safest for all types of oxygen service.

  19. What Factors Affect Response to Ads? A Perspective.

    ERIC Educational Resources Information Center

    Rotzoll, Kim B.

    The concept of "frame of reference" offers a perspective from which to examine the many factors which affect advertising response. The advertiser is interested in affecting two types of overt behavior. First, the individual is induced to select a particular stimulus (the advertisement) from competing stimuli (such as other people, noise,…

  20. Study of the factors influencing the metals solubilisation from a mixture of waste batteries by response surface methodology.

    PubMed

    Tanong, Kulchaya; Coudert, Lucie; Chartier, Myriam; Mercier, Guy; Blais, Jean-François

    2017-12-01

    This paper presents an innovative process for the recovery of valuable metals from a mixture of spent batteries. Different types of batteries, including alkaline, zinc-carbon (Zn-C), nickel cadmium (Ni-Cd), nickel metal hydride (Ni-MH), lithium ion (Li-ion) and lithium metallic (Li-M) batteries, were mixed according to the proportion of the Canadian sales of batteries. A Box-Behnken design was applied to find the optimum leaching conditions allowing a maximum of valuable metal removals from a mixture of spent batteries in the presence of an inorganic acid and a reducing agent. The results highlighted the positive effect of sodium metabisulfite on the performance of metals removal, especially for Mn. The solid/liquid ratio and the concentration of H 2 SO 4 were the main factors affecting the leaching behavior of valuable metals (Zn, Mn, Cd, Ni) present in spent batteries. Finally, the optimum leaching conditions were found as follows: one leaching step, solid/liquid ratio = 10.9%, [H 2 SO 4 ] = 1.34 M, sodium metabisulfite (Na 2 S 2 O 5 ) = 0.45 g/g of battery powder and retention time = 45 min. Under such conditions, the removal yields achieved were 94% for Mn, 81% for Cd, 99% for Zn, 96% for Co and 68% for Ni.

  1. Mechanisms of Metal Resistance and Homeostasis in Haloarchaea

    PubMed Central

    Srivastava, Pallavee; Kowshik, Meenal

    2013-01-01

    Haloarchaea are the predominant microflora of hypersaline econiches such as solar salterns, soda lakes, and estuaries where the salinity ranges from 35 to 400 ppt. Econiches like estuaries and solar crystallizer ponds may contain high concentrations of metals since they serve as ecological sinks for metal pollution and also as effective traps for river borne metals. The availability of metals in these econiches is determined by the type of metal complexes formed and the solubility of the metal species at such high salinity. Haloarchaea have developed specialized mechanisms for the uptake of metals required for various key physiological processes and are not readily available at high salinity, beside evolving resistance mechanisms for metals with high solubility. The present paper seeks to give an overview of the main molecular mechanisms involved in metal tolerance in haloarchaea and focuses on factors such as salinity and metal speciation that affect the bioavailability of metals to haloarchaea. Global transcriptomic analysis during metal stress in these organisms will help in determining the various factors differentially regulated and essential for metal physiology. PMID:23533331

  2. Municipal sludge metal contamination of old-field ecosystems: Do liming and tilling affect remediation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Benninger-Truax, M.; Taylor, D.H.

    1993-10-01

    Mechanisms of ecosystem recovery following 11 years of sewage sludge disposal were addressed by examining the effects of tilling and/or liming on soil chemistry and the heavy metal (Cd, Cu, Pb, and Zn) concentrations in soil, earthworms, vegetation, spiders, and crickets. In 1989 and 1990, subplots in each of three former 0.1-ha, long-term treatments (sludge, fertilizer, and control) were either unmanipulated or manipulated via tilling and/or liming. Liming significantly increased the pH of soil from the long-term sludge and fertilizer plots, and the combination of tilling and liming affected the heavy metal concentrations in earthworms, as lower concentrations of Cd,more » Cu, Pb, and Zn were found in earthworms collected from subplots that had been both tilled and limed. However, most observed significant differences in heavy metal concentrations reflected the long-term treatments, as heavy metal concentrations tended to be greater in the soil and biota collected from sludge-treated plots. Thus, heavy metals remained in the soil in forms available to the biota, regardless of the cessation of sludge application or subplot manipulations (liming and/or tilling) for two years following cessation of sludge application.« less

  3. Affective and Social Factors in a Project-Based Writing Course

    ERIC Educational Resources Information Center

    Kathpalia, Sujata Surinder; Heah, Carmel

    2011-01-01

    Much of the work in academic writing has focused on the cognitive rather than the affective and social aspects involved in project-based writing. Emphasis in past research has been on skills and processes of writing rather than on affective factors such as motivation, attitudes, feelings or social factors involving intrapersonal and interpersonal…

  4. Substrate-Related Factors Affecting Enzymatic Saccharification of Lignocelluloses: Our Recent Understanding

    Treesearch

    Shao-Yuan Leu; J.Y. Zhu

    2013-01-01

    Enzymatic saccharification of cellulose is a key step in conversion of plant biomass to advanced biofuel and chemicals. Many substrate-related factors affect saccharification. Rather than examining the role of each individual factor on overall saccharification efficiency, this study examined how each factor affects the three basic processes of a heterogeneous...

  5. EFFECT OF SOIL MODIFYING FACTORS ON THE BIOAVAILABILITY AND TOXICITY OF METAL CONTAMINATED SOILS

    EPA Science Inventory

    Heavy metal and organic chemical contamination of soils is a worldwide problem posing a risk to humans and more directly, soil organisms. Metal toxicity is often not directly related to the total concentration of metals present due to a number of modifying factors that depend,...

  6. Microbiologic factors affecting Clostridium difficile recurrence.

    PubMed

    Chilton, C H; Pickering, D S; Freeman, J

    2018-05-01

    Recurrent Clostridium difficile infection (rCDI) places a huge economic and practical burden on healthcare facilities. Furthermore, rCDI may affect quality of life, leaving patients in an rCDI cycle and dependant on antibiotic therapy. To discuss the importance of microbiologic factors in the development of rCDI. Literature was drawn from a search of PubMed from 2000 onwards with the search term 'recurrent Clostridium difficile infection' and further references cited within these articles. Meta-analyses and systematic reviews have shown that CDI and rCDI risk factors are similar. Development of rCDI is attendant on many factors, including immune status or function, comorbidities and concomitant treatments. Studies suggest that poor bacterial diversity is correlated with clinical rCDI. Narrow-spectrum gut microflora-sparing antimicrobials (e.g. surotomycin, cadazolid, ridinilazole) are in development for CDI treatment, while microbiota therapeutics (faecal microbiota transplantation, nontoxigenic C. difficile, stool substitutes) are increasingly being explored. rCDI can only occur when viable C. difficile spores are present, either within the gut lumen after infection or when reacquired from the environment. C. difficile spore germination can be influenced by gut environmental factors resulting from dysbiosis, and spore outgrowth may be affected stage by some antimicrobials (e.g. fidaxomicin, ramoplanin, oritavancin). rCDI is a significant challenge for healthcare professionals, requiring a multifaceted approach; optimized infection control to minimize reinfection; C. difficile-targeted antibiotics to minimize dysbiosis; and gut microflora restoration to promote colonization resistance. These elements should be informed by our understanding of the microbiologic factors involved in both C. difficile itself and the gut microbiome. Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  7. Ion implantation enhanced metal-Si-metal photodetectors

    NASA Astrophysics Data System (ADS)

    Sharma, A. K.; Scott, K. A. M.; Brueck, S. R. J.; Zolper, J. C.; Myers, D. R.

    1994-05-01

    The quantum efficiency and frequency response of simple Ni-Si-Ni metal-semiconductor-metal (MSM) photodetectors at long wavelengths are significantly enhanced with a simple, ion-implantation step to create a highly absorbing region approx. 1 micron below the Si surface. The internal quantum efficiency is improved by a factor of approx. 3 at 860 nm (to 64%) and a full factor of ten at 1.06 microns (to 23%) as compared with otherwise identical unimplanted devices. Dark currents are only slightly affected by the implantation process and are as low as 630 pA for a 4.5-micron gap device at 10-V bias. Dramatic improvement in the impulse response is observed, 100 ps vs. 600 ps, also at 10-V bias and 4.5-micron gap, due to the elimination of carrier diffusion tails in the implanted devices. Due to its planar structure, this device is fully VLSI compatible. Potential applications include optical interconnections for local area networks and multi-chip modules.

  8. Heavy metal fractions and ecological risk assessment in sediments from urban, rural and reclamation-affected rivers of the Pearl River Estuary, China.

    PubMed

    Zhang, Guangliang; Bai, Junhong; Xiao, Rong; Zhao, Qingqing; Jia, Jia; Cui, Baoshan; Liu, Xinhui

    2017-10-01

    Rapid urbanization and reclamation processes in coastal areas have resulted in serious pollution to the aquatic environment. Less is known on the geochemical fractions and ecological risks in river sediment under various human activities pressures, which is essential for addressing the connections between heavy metal pollution and anthropogenic influences. River sediments were collected from different landscapes (i.e., urban, rural and reclamation areas) to investigate the impacts of urbanization and reclamation on the metallic pollution levels and ecological risks in the Pear River Estuary of China. Results showed that Cd, Zn and Cu with high total contents and geoaccumulation index (I geo ) were the primary metals in the Peal River sediments. Generally, urban river sediments, especially the surface sediment layer (0-10 cm), exhibited higher metallic pollution levels. As for geochemical fractions, reducible and residual fractions were the dominant forms for six determined metals. And the percentage of heavy metals bound to Fe-Mn oxides decreased with increasing soil depth but the reverse tendency was observed for residual fractions. Compared with rural river sediments, heavy metals were highly associated with the exchangeable and carbonate fractions in both urban and reclamation-affected river sediments, suggesting that anthropogenic activities mainly increased the active forms of metals. Approximately 80% of Cd existed in the non-residual fraction and posed medium to high ecological risk according to the risk assessment code (RAC) values. The redundancy analysis (RDA) revealed that both urbanization and reclamation processes would cause similar metallic characteristics, and sediment organic matter (SOC) might be the prominent influencing factor. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Factors affecting strategic plan implementation using interpretive structural modeling (ISM).

    PubMed

    Bahadori, Mohammadkarim; Teymourzadeh, Ehsan; Tajik, Hamidreza; Ravangard, Ramin; Raadabadi, Mehdi; Hosseini, Seyed Mojtaba

    2018-06-11

    Purpose Strategic planning is the best tool for managers seeking an informed presence and participation in the market without surrendering to changes. Strategic planning enables managers to achieve their organizational goals and objectives. Hospital goals, such as improving service quality and increasing patient satisfaction cannot be achieved if agreed strategies are not implemented. The purpose of this paper is to investigate the factors affecting strategic plan implementation in one teaching hospital using interpretive structural modeling (ISM). Design/methodology/approach The authors used a descriptive study involving experts and senior managers; 16 were selected as the study sample using a purposive sampling method. Data were collected using a questionnaire designed and prepared based on previous studies. Data were analyzed using ISM. Findings Five main factors affected strategic plan implementation. Although all five variables and factors are top level, "senior manager awareness and participation in the strategic planning process" and "creating and maintaining team participation in the strategic planning process" had maximum drive power. "Organizational structure effects on the strategic planning process" and "Organizational culture effects on the strategic planning process" had maximum dependence power. Practical implications Identifying factors affecting strategic plan implementation is a basis for healthcare quality improvement by analyzing the relationship among factors and overcoming the barriers. Originality/value The authors used ISM to analyze the relationship between factors affecting strategic plan implementation.

  10. [Levels of awareness of occupational and general cardiovascular risk factors among metal industry employees].

    PubMed

    Gürdoğan, Muhammet; Paslı Gürdoğan, Eylem; Arı, Hasan; Ertürk, Mehmet; Genç, Ahmet; Uçar, Mehmet Fatih

    2015-06-01

    Long-term exposure to physical, chemical, ergonomic and psychosocial environmental factors may lead to occupational cardiovascular disease in metal industry employees. This study aimed to determine levels of knowledge levels regarding occupational and cardiovascular risk factors among metal industry employees. The study was conducted between 2nd and 6th June 2014 with the participation of 82 employees. All were working in a medium-sized workplace in the metal industry. Data were collected by means of a questionnaire, which included socio-demographic characteristics and occupational cardiovascular risk factors, and a scale developed by Arıkan et al. to measure awareness levels of risk factors for cardiovascular diseases (CARRF-KL). The mean age of employees was 39.97±8.44. Of the participants, 58.5% stated that they had knowledge on cardiac disease risk factors. The mean CARRF-KL score was found to be 18.65±4.04. The percentage of employees stating that they had no knowledge on the occupational risks for such diseases was 79.3%, while 19.5% stated that job stress caused cardiac diseases. One individual (1.2%) stated that one of the chemical solvents used in the working environment was a risk factor. Although awareness among metal industry employees of cardiovascular risk factors was above average, it was determined that they do not have adequate information on occupational risk factors. Prolonged and unprotected levels exposure to environmental factors constitute a risk for cardiovascular disease. This information is important for the development of preventive cardiology.

  11. Exploring paraprofessional and classroom factors affecting teacher supervision.

    PubMed

    Irvin, Dwight W; Ingram, Paul; Huffman, Jonathan; Mason, Rose; Wills, Howard

    2018-02-01

    Paraprofessionals serve a primary role in supporting students with disabilities in the classroom, which necessitates teachers' supervision as a means to improve their practice. Yet, little is known regarding what factors affect teacher supervision. We sought to identify how paraprofessional competence and classroom type affected the levels of teacher direction. We administered an adapted version of the Paraprofessional Needs, Knowledge & Tasks Survey and the Survey for Teachers Supervising Paraprofessionals to teachers supervising paraprofessionals in elementary schools. Structural Equation Modeling was used to examine the link between paraprofessional competence and classroom factors affecting the level of teacher supervision. Our results indicated that when teachers perceived paraprofessionals as being more skilled, they provided more supervision, and when more supervision was provided the less they thought paraprofessionals should be doing their assigned tasks. Additionally, paraprofessionals working in classrooms with more students with mild disabilities received less supervision than paraprofessionals working in classrooms with more students with moderate-to-severe disabilities. Those paraprofessionals in classrooms serving mostly children with mild disabilities were also perceived as having lower levels of skill competence than those serving in classrooms with students with more moderate-to-severe disabilities. By understanding the factors that affect teacher supervision, policy and professional development opportunities can be refined/developed to better support both supervising teachers and paraprofessionals and, in turn, improve the outcomes of children with disabilities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Ranking factors affecting emissions of GHG from incubated agricultural soils.

    PubMed

    García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

    2014-07-01

    Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO 3 - ) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L 16 design, comprising 16 experimental units. Within this L 16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO 3 - addition were the main factors affecting N 2 O fluxes, whilst glucose, NO 3 - and soil temperature were the main factors affecting CO 2 and CH 4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time.

  13. Ranking factors affecting emissions of GHG from incubated agricultural soils

    PubMed Central

    García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

    2014-01-01

    Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO3−) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L16 design, comprising 16 experimental units. Within this L16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO3− addition were the main factors affecting N2O fluxes, whilst glucose, NO3− and soil temperature were the main factors affecting CO2 and CH4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time. PMID:25177207

  14. Clinical usefulness of blood metal measurements to assess the failure of metal-on-metal hip implants

    PubMed Central

    Sampson, Barry; Hart, Alister

    2012-01-01

    In April 2010, a Medicines and Healthcare Products Regulatory Agency safety alert concerning all metal-on-metal (MOM) hip replacements recommended measuring chromium and cobalt concentrations when managing patients with painful prostheses. The need for this review is illustrated by the recent surge in requests for these blood tests from orthopaedic surgeons following this alert. The aim is to provide guidance to laboratories in assessing these requests and advising clinicians on interpretation. First, we summarize the basic terminology regarding the types of hip replacements, with emphasis on the MOM type. Second, we describe the clinical concerns over implant-derived wear debris in the local tissues and distant sites. Analytical aspects of the measurement of the relevant metal ions and what factors affect the levels measured are discussed. The application of inductively coupled plasma mass spectrometry techniques to the measurement of these metals is considered in detail. The biological effects of metal wear products are summarized with local toxicity and systemic biological effects considered, including carcinogenicity, genotoxicity and systemic toxicity. Clinical cases are used to illustrate pertinent points. PMID:22155921

  15. Influence of market factors on the pricing of exchange traded metals in the medium term

    NASA Astrophysics Data System (ADS)

    Bogdanov, S. V.; Shevelev, I. M.; Chernyi, S. A.

    2017-06-01

    On the basis of comparison of the influence of the stock exchange factors on the pricing of nonferrous metals for medium term with similar results for short term, it has been established that the main attention should be paid to the changes in the pricing environment on the metal market as a function of the prices of exchange traded metals. The situation on the market of energy carriers (hydrocarbons) and the European, American, and Asian stock exchanges can be based on parity and even significantly influence the variation of the metal prices. In the medium term, constructive development of metal trade should be reasonably promoted by changing the elasticity of supply with regard to prices for exchange traded metals and by applying the stock exchange factors that positively influence the pricing on commodity and stock markets.

  16. Climate change driven plant-metal-microbe interactions.

    PubMed

    Rajkumar, Mani; Prasad, Majeti Narasimha Vara; Swaminathan, Sandhya; Freitas, Helena

    2013-03-01

    Various biotic and abiotic stress factors affect the growth and productivity of crop plants. Particularly, the climatic and/or heavy metal stress influence various processes including growth, physiology, biochemistry, and yield of crops. Climatic changes particularly the elevated atmospheric CO₂ enhance the biomass production and metal accumulation in plants and help plants to support greater microbial populations and/or protect the microorganisms against the impacts of heavy metals. Besides, the indirect effects of climatic change (e.g., changes in the function and structure of plant roots and diversity and activity of rhizosphere microbes) would lead to altered metal bioavailability in soils and concomitantly affect plant growth. However, the effects of warming, drought or combined climatic stress on plant growth and metal accumulation vary substantially across physico-chemico-biological properties of the environment (e.g., soil pH, heavy metal type and its bio-available concentrations, microbial diversity, and interactive effects of climatic factors) and plant used. Overall, direct and/or indirect effects of climate change on heavy metal mobility in soils may further hinder the ability of plants to adapt and make them more susceptible to stress. Here, we review and discuss how the climatic parameters including atmospheric CO₂, temperature and drought influence the plant-metal interaction in polluted soils. Other aspects including the effects of climate change and heavy metals on plant-microbe interaction, heavy metal phytoremediation and safety of food and feed are also discussed. This review shows that predicting how plant-metal interaction responds to altering climatic change is critical to select suitable crop plants that would be able to produce more yields and tolerate multi-stress conditions without accumulating toxic heavy metals for future food security. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Reviews on factors affecting fatigue behavior of high-Mn steels

    NASA Astrophysics Data System (ADS)

    Kim, Sangshik; Jeong, Daeho; Sung, Hyokyung

    2018-01-01

    A variety of factors affect the fatigue behavior of high-Mn steels, which include both extrinsic (i.e., loading type, R ratio, specimen type, surface condition, temperature, and environment) and intrinsic (i.e., chemical composition, grain size, microstructure, stacking fault energy) factors. Very often, the influence of extrinsic factors on the fatigue behavior is even greater than that of intrinsic factors, misleading the interpretation of fatigue data. The metallurgical factors influence the initiation and propagation behaviors of fatigue by altering the characteristics of slip that is prerequisite for fatigue damage accumulation. It is however not easy to separate the effect of each factor since they affect the fatigue behavior of high-Mn steels in complex and synergistic way. In this review, the fatigue data of high-Mn steels are summarized and the factors complicating the interpretation are discussed.

  18. Review: Factors affecting fouling in conventional pens for slaughter pigs.

    PubMed

    Larsen, M L V; Bertelsen, M; Pedersen, L J

    2018-02-01

    This review assesses factors affecting fouling in conventional pens for slaughter pigs. Fouling of the pen happens when pigs change their excretory behaviour from occurring in the designated dunging area to the lying area. This can result in a lower hygiene, bad air quality, extra work for the farmer, disturbance of the pigs' resting behaviour and an increase in agonistic interactions. A systematic search was conducted and results narrowed down to 21 articles. Four factors were found to affect fouling directly: insufficient space allowance, the flooring design of the pen, the thermal climate and pigs' earlier experience. Further, these primary factors are affected by secondary factors such as the shape of the pen, the weight of the pigs and especially the heat balance of the pigs, which is affected by several tertiary factors including, for example, temperature, humidity and draught. Results indicate that the most important factor to control when trying to prevent fouling of a pen is the pen climate. An appropriate climate may be accomplished through floor cooling in the designated lying area, sprinklers above the designated dunging area and by ensuring a more optimal ambient temperature curve that also fits the weight of the pigs in different stages of the production. All in all, fouling of the pen in conventional slaughter pigs is a multifactorial problem, but it is important to focus on increasing the comfortability, and especially the climate, of the designated lying area.

  19. Debye-Waller Factor in Neutron Scattering by Ferromagnetic Metals

    NASA Astrophysics Data System (ADS)

    Paradezhenko, G. V.; Melnikov, N. B.; Reser, B. I.

    2018-04-01

    We obtain an expression for the neutron scattering cross section in the case of an arbitrary interaction of the neutron with the crystal. We give a concise, simple derivation of the Debye-Waller factor as a function of the scattering vector and the temperature. For ferromagnetic metals above the Curie temperature, we estimate the Debye-Waller factor in the range of scattering vectors characteristic of polarized magnetic neutron scattering experiments. In the example of iron, we compare the results of harmonic and anharmonic approximations.

  20. Quantification of Stereochemical Communication in Metal-Organic Assemblies.

    PubMed

    Castilla, Ana M; Miller, Mark A; Nitschke, Jonathan R; Smulders, Maarten M J

    2016-08-26

    The derivation and application of a statistical mechanical model to quantify stereochemical communication in metal-organic assemblies is reported. The factors affecting the stereochemical communication within and between the metal stereocenters of the assemblies were experimentally studied by optical spectroscopy and analyzed in terms of a free energy penalty per "incorrect" amine enantiomer incorporated, and a free energy of coupling between stereocenters. These intra- and inter-vertex coupling constants are used to track the degree of stereochemical communication across a range of metal-organic assemblies (employing different ligands, peripheral amines, and metals); temperature-dependent equilibria between diastereomeric cages are also quantified. The model thus provides a unified understanding of the factors that shape the chirotopic void spaces enclosed by metal-organic container molecules. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  1. Factors affecting the quality of life in childhood epilepsy in China.

    PubMed

    Yong, L; Chengye, J; Jiong, Q

    2006-03-01

    To explore the level of, and factors affecting the quality of life (QOL) in childhood epilepsy in China. At the Peking University First Hospital, we consecutively identified 418 parents whose children were with known epilepsy to complete a questionnaire, which included children's demographic characteristics, clinical message of epilepsy, QOL, familial message, parental symptoms of anxiety/depression. Significant (p<0.05) affecting factors of children's quality of life included current educational degree, mental development, age at diagnosis, age at onset, seizure frequency, duration, AED number; parental significant (p<0.05) affecting factors included anxiety, depression and health. On regression analysis, parental anxiety was the most important factor in explaining lower QOL in childhood epilepsy. AEDs, familial economic state, paternal career, seizure frequency were also significant factors. Parental anxiety outweighed the physical factors in determining QOL in childhood epilepsy. Recognition of this will be helpful for professionals to treat disease and improve the QOL of childhood epilepsy.

  2. Soil and plant factors influencing the accumulation of heavy metals by plants.

    PubMed Central

    Cataldo, D A; Wildung, R E

    1978-01-01

    The use of plants to monitor heavy metal pollution in the terrestrial environment must be based on a cognizance of the complicated, integrated effects of pollutant source and soil-plant variables. To be detectable in plants, pollutant sources must significantly increase the plant available metal concentration in soil. The major factor governing metal availability to plants in soils is the solubility of the metal associated with the solid phase, since in order for root uptake to occur, a soluble species must exist adjacent to the root membrane for some finite period. The rate of release and form of this soluble species will have a strong influence on the rate and extent of uptake and, perhaps, mobility and toxicity in the plant and consuming animals. The factors influencing solubility and form of available metal species in soil vary widely geographically and include the concentration and chemical form of the element entering soil, soil properties (endogenous metal concentration, mineralogy, particle size distribution), and soil processes (e.g., mineral weathering, microbial activity), as these influence the kinetics of sorption reactions, metal concentration in solution and the form of soluble and insoluble chemical species. The plant root represents the first barrier to the selective accumulation of ions present in soil solution. Uptake and kinetic data for nutrient ions and chemically related nonnutrient analogs suggest that metabolic processes associated with root absorption of nutrients regulate both the affinity and rate of absorption of specific nonnutrient ions. Detailed kinetic studies of Ni, Cd, and Tl uptake by intact plants demonstrate multiphasic root absorption processes over a broad concentration range, and the use of transport mechanisms in place for the nutrient ions Cu, Zn, and K. Advantages and limitations of higher plants as indicators of increased levels of metal pollution are discussed in terms of these soil and plant phenomena. PMID:367766

  3. Factors affecting academic leadership in dermatology.

    PubMed

    Martires, Kathryn J; Aquino, Lisa L; Wu, Jashin J

    2015-02-01

    Although prior studies have examined methods by which to recruit and retain academic dermatologists, few have examined factors that are important for developing academic leaders in dermatology. This study sought to examine characteristics of dermatology residency programs that affect the odds of producing department or division chairs/chiefs and program directors (PDs). Data regarding program size, faculty, grants, alumni residency program attended, lectures, and publications for all accredited US dermatology residency programs were collected. Of the 103 programs examined, 46% had graduated at least 1 chair/chief, and 53% had graduated at least 1 PD. Results emphasize that faculty guidance and research may represent modifiable factors by which a dermatology residency program can increase its graduation of academic leaders.

  4. In depth analysis of the mechanism of action of metal-dependent sigma factors: characterization of CorE2 from Myxococcus xanthus

    PubMed Central

    Marcos-Torres, Francisco Javier; Pérez, Juana; Gómez-Santos, Nuria; Moraleda-Muñoz, Aurelio; Muñoz-Dorado, José

    2016-01-01

    Extracytoplasmic function sigma factors represent the third pillar of signal-transduction mechanisms in bacteria. The variety of stimuli they recognize and mechanisms of action they use have allowed their classification into more than 50 groups. We have characterized CorE2 from Myxococcus xanthus, which belongs to group ECF44 and upregulates the expression of two genes when it is activated by cadmium and zinc. Sigma factors of this group contain a Cys-rich domain (CRD) at the C terminus which is essential for detecting metals. Point mutations at the six Cys residues of the CRD have revealed the contribution of each residue to CorE2 activity. Some of them are essential, while others are either dispensable or their mutations only slightly affect the activity of the protein. However, importantly, mutation of Cys174 completely shifts the specificity of CorE2 from cadmium to copper, indicating that the Cys arrangement of the CRD determines the metal specificity. Moreover, the conserved CxC motif located between the σ2 domain and the σ4.2 region has also been found to be essential for activity. The results presented here contribute to our understanding of the mechanism of action of metal-dependent sigma factors and help to define new common features of the members of this group of regulators. PMID:26951374

  5. 78 FR 46418 - Proposed Information Collection (Obligation To Report Factors Affecting Entitlement) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... (Obligation To Report Factors Affecting Entitlement) Activity; Comment Request AGENCY: Veterans Benefits... use of other forms of information technology. Title: Obligation to Report Factors Affecting... entitlement factors. Individual factors such as income, marital status, and the beneficiary's number of...

  6. 75 FR 62634 - Proposed Information Collection (Obligation to Report Factors Affecting Entitlement) Activity...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... (Obligation to Report Factors Affecting Entitlement) Activity: Comment Request AGENCY: Veterans Benefits... use of other forms of information technology. Title: Obligation to Report Factors Affecting... entitlement factors. Individual factors such as income, marital status, and the beneficiary's number of...

  7. Analysis of factors affecting employee satisfaction: A case study from Pakistan.

    PubMed

    Rukh, Lala; Choudhary, Muhammad Abbas; Abbasi, Saddam Akber

    2015-01-01

    Employee job satisfaction has been a research focal point throughout the world. It is a key factor when measuring the performance of an organization and individuals. A leading engineering goods manufacturing enterprise in Pakistan, has been used in this case study. In Pakistan, very limited research has been done with respect to factors affecting job satisfaction. Some research has been done in medical institutions, banks, universities and the information technology sector but large public sector organizations in Pakistan have not been studied. A theoretical foundation for researching factors affecting job satisfaction in large organizations is outlined. The objective of this research is to analyze various demographic, financial and non-financial factors affecting the satisfaction level of employees and to study the effects across different employee groups. This study is based on quantitative data analysis. The employees of the organization under study have been divided into 10 homogeneous groups based on their departments. Information on job related factors (affecting the satisfaction level) have been collected from subsamples of each group using a self-administered questionnaire. An overall sample of 250 (out of total 1100) employees has been selected. Before conducting the survey, reliability of the questionnaire was measured using Cronbach's alpha. The normality of data was also examined using the Kolmogorov Smirnov test. Hypotheses devised to address the research questions were tested by using non-parametric Spearman correlation and Kruskal-Wallis tests. The response rate was 73.2%. Research findings indicated the significant factors that affect the satisfaction level of employees. Median group differences existed between responses based on age, work experience, salary and designation (i.e. job position/rank) of employees. Job satisfaction was also positively and significantly associated with job related factors such as pay, promotion, relation with employees

  8. Factors Affecting Successful Implementation of Hospital Information Systems.

    PubMed

    Farzandipur, Mehrdad; Jeddi, Fatemeh Rangraz; Azimi, Esmaeil

    2016-02-01

    Today, the use of information systems in health environments, like any other fields, is necessary and organizational managers are convinced to use these systems. However, managers' satisfaction is not the only factor in successfully implementing these systems and failed information technology projects (IT) are reported despite the consent of the directors. Therefore, this study aims to determine the factors affecting the successful implementation of a hospital information system. The study was carried out as a descriptive method in 20 clinical hospitals that the hospital information system (HIS) was conducted in them. The clinical and paraclinical users of mentioned hospitals are the study group. 400 people were chosen as samples in scientific method and the data was collected using a questionnaire consisted of three main human, managerial and organizational, and technological factors, by questionnaire and interview. Then the data was scored in Likert scale (score of 1 to 5) and were analyzed using the SPSS software. About 75 percent of the population were female, with average work experience of 10 years and the mean age was 30 years. The human factors affecting the success of hospital information system implementation achieved the mean score of 3.5, both organizational and managerial factors 2.9 and technological factors the mean of 3. Human factors including computer skills, perceiving usefulness and perceiving the ease of a hospital information system use are more effective on the acceptance and successful implementation of hospital information systems; then the technological factors play a greater role. It is recommended that for the successful implementation of hospital information systems, most of these factors to be considered.

  9. Factors Affecting Open-Set Word Recognition in Adults with Cochlear Implants

    PubMed Central

    Holden, Laura K.; Finley, Charles C.; Firszt, Jill B.; Holden, Timothy A.; Brenner, Christine; Potts, Lisa G.; Gotter, Brenda D.; Vanderhoof, Sallie S.; Mispagel, Karen; Heydebrand, Gitry; Skinner, Margaret W.

    2012-01-01

    A monosyllabic word test was administered to 114 postlingually-deaf adult cochlear implant (CI) recipients at numerous intervals from two weeks to two years post-initial CI activation. Biographic/audiologic information, electrode position, and cognitive ability were examined to determine factors affecting CI outcomes. Results revealed that Duration of Severe-to-Profound Hearing Loss, Age at Implantation, CI Sound-field Threshold Levels, Percentage of Electrodes in Scala Vestibuli, Medio-lateral Electrode Position, Insertion Depth, and Cognition were among the factors that affected performance. Knowledge of how factors affect performance can influence counseling, device fitting, and rehabilitation for patients and may contribute to improved device design. PMID:23348845

  10. Factors affecting self-regulated learning in medical students: a qualitative study

    PubMed Central

    Jouhari, Zahra; Haghani, Fariba; Changiz, Tahereh

    2015-01-01

    Introduction Clinical courses are required of all medical students and means that they must develop the key skill of self-regulation during learning. The ability to self-regulate learning strategies is affected by different factors. This study determined the views of medical students on the factors affecting self-regulated learning (SRL). Method This study uses a qualitative approach and the content analysis method. Nineteen medical students in their fourth, fifth, and sixth years of study at Isfahan University of Medical Science participated in semi-structured, in-depth interviews. The students were selected using purposive sampling based on their overall grade point average (GPA). Results Five main themes were found to affect SRL. These themes included family with the two subthemes of family supervisory and supportive roles; peers with the two subthemes of facilitating and inhibiting roles; instructors with the two subthemes of personal and educational instructor's characteristics; educational environment with the two subthemes of facilitator and inhibitor roles; and student with the two subthemes of facilitating and inhibiting personal factors. Conclusion The outcomes of student understanding of the factors affecting self-regulation indicate that facilitating factors should be used on an individual basis to reduce the effect of inhibiting factors to improve self-regulation in students. PMID:26549046

  11. Factors affecting self-regulated learning in medical students: a qualitative study.

    PubMed

    Jouhari, Zahra; Haghani, Fariba; Changiz, Tahereh

    2015-01-01

    Introduction Clinical courses are required of all medical students and means that they must develop the key skill of self-regulation during learning. The ability to self-regulate learning strategies is affected by different factors. This study determined the views of medical students on the factors affecting self-regulated learning (SRL). Method This study uses a qualitative approach and the content analysis method. Nineteen medical students in their fourth, fifth, and sixth years of study at Isfahan University of Medical Science participated in semi-structured, in-depth interviews. The students were selected using purposive sampling based on their overall grade point average (GPA). Results Five main themes were found to affect SRL. These themes included family with the two subthemes of family supervisory and supportive roles; peers with the two subthemes of facilitating and inhibiting roles; instructors with the two subthemes of personal and educational instructor's characteristics; educational environment with the two subthemes of facilitator and inhibitor roles; and student with the two subthemes of facilitating and inhibiting personal factors. Conclusion The outcomes of student understanding of the factors affecting self-regulation indicate that facilitating factors should be used on an individual basis to reduce the effect of inhibiting factors to improve self-regulation in students.

  12. Factors affecting self-regulated learning in medical students: a qualitative study.

    PubMed

    Jouhari, Zahra; Haghani, Fariba; Changiz, Tahereh

    2015-01-01

    Clinical courses are required of all medical students and means that they must develop the key skill of self-regulation during learning. The ability to self-regulate learning strategies is affected by different factors. This study determined the views of medical students on the factors affecting self-regulated learning (SRL). This study uses a qualitative approach and the content analysis method. Nineteen medical students in their fourth, fifth, and sixth years of study at Isfahan University of Medical Science participated in semi-structured, in-depth interviews. The students were selected using purposive sampling based on their overall grade point average (GPA). Five main themes were found to affect SRL. These themes included family with the two subthemes of family supervisory and supportive roles; peers with the two subthemes of facilitating and inhibiting roles; instructors with the two subthemes of personal and educational instructor's characteristics; educational environment with the two subthemes of facilitator and inhibitor roles; and student with the two subthemes of facilitating and inhibiting personal factors. The outcomes of student understanding of the factors affecting self-regulation indicate that facilitating factors should be used on an individual basis to reduce the effect of inhibiting factors to improve self-regulation in students.

  13. Heavy metal leaching from mine tailings as affected by plants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhu, D.; Schwab, A.P.; Banks, M.K.

    A column experiment was conducted to determine the impact of soil cover and plants on heavy metal leaching from mine tailings and heavy metal contaminated soil. Columns made of PVC were constructed with 30 cm subsoil covered by 30 cm of mine tailings followed by 0, 30, or 60 cm subsoil covered by 30 cm of mine tailings followed by 0, 30, or 60 cm of clean topsoil. Two grasses, tall fescue (Festuca arundinacea Schreb.) and big bluestem (Andropogon gerardii), were grown in the columns. The columns were leached at a slow rate for 1 yr with a 0.001 Mmore » CaCl{sub 2} solution under unsaturated conditions. The presence of both tall fescue and big bluestem increased Zn and Cd concentrations in the leachate. Lead concentrations in leachates were not affected by the presence of plants. Although plants generally reduced the total amount of water leached, total mass of Zn and Cd leached generally was not impacted by plants. Total mass of Pb leached was positively correlated with total leachate collected from each column. Covering the mine tailings with 60 cm of topsoil increased the mass of Zn and Cd leached relative to no topsoil. When the subsoil was absent, Zn and Cd leaching increased by as much as 20-fold, verifying the ability of soil to act as a sink for metals. Mine tailing remediation by establishing vegetation can reduce Pb movement but may enhance short-term Cd and Zn leaching. However, the changes were relatively small and do not outweigh the benefits of using vegetation in mine tailings reclamation.« less

  14. 14 CFR Appendix B to Part 1215 - Factors Affecting Standard Charges

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Factors Affecting Standard Charges B Appendix B to Part 1215 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION TRACKING AND DATA RELAY SATELLITE SYSTEM (TDRSS) Pt. 1215, App. B Appendix B to Part 1215—Factors Affecting Standard...

  15. Metal matrix composites: History, status, factors and future

    NASA Astrophysics Data System (ADS)

    Cyriac, Ajith James

    The history, status, and future of metal matrix composites are presented by evaluating the progression of available literature through time. The trends that existed and issues that still prevail are discussed and a prediction of the future for MMCs is presented. The factors that govern the performance of metal matrix composites are also discussed. In many developed countries and in several developing countries there exists continued interest in MMCs. Researchers tried numerous combinations of matrices and reinforcements since work strictly on MMCs began in the 1950s. This led to developments for aerospace and defense applications, but resultant commercial applications were limited. The introduction of ceramic whiskers as reinforcement and the development of 'in-situ' eutectics in the 1960s aided high temperature applications in aircraft engines. In the late 1970s the automobile industries started to take MMCs seriously. In the last 20 years, MMCs evolved from laboratories to a class of materials with numerous applications and commercial markets. After the collapse of the Berlin Wall, prevailing order in the world changed drastically. This effect was evident in the progression of metal matrix composites. The internet connected the world like never before and tremendous information was available for researchers around the world. Globalization and the internet resulted in the transformation of the world to a more level playing field, and this effect is evident in the nature and source of research on metal matrix composites happening around the world.

  16. Methods of Combinatorial Optimization to Reveal Factors Affecting Gene Length

    PubMed Central

    Bolshoy, Alexander; Tatarinova, Tatiana

    2012-01-01

    In this paper we present a novel method for genome ranking according to gene lengths. The main outcomes described in this paper are the following: the formulation of the genome ranking problem, presentation of relevant approaches to solve it, and the demonstration of preliminary results from prokaryotic genomes ordering. Using a subset of prokaryotic genomes, we attempted to uncover factors affecting gene length. We have demonstrated that hyperthermophilic species have shorter genes as compared with mesophilic organisms, which probably means that environmental factors affect gene length. Moreover, these preliminary results show that environmental factors group together in ranking evolutionary distant species. PMID:23300345

  17. Directional Emission from Metal-Dielectric-Metal Structures: Effect of Mixed Metal Layers, Dye Location and Dielectric Thickness.

    PubMed

    Choudhury, Sharmistha Dutta; Badugu, Ramachandram; Ray, Krishanu; Lakowicz, Joseph R

    2015-02-12

    Metal-dielectric-metal (MDM) structures provide directional emission close to the surface normal, which offers opportunities for new design formats in fluorescence based applications. The directional emission arises due to near-field coupling of fluorophores with the optical modes present in the MDM substrate. Reflectivity simulations and dispersion diagrams provide a basic understanding of the mode profiles and the factors that affect the coupling efficiency and the spatial distribution of the coupled emission. This work reveals that the composition of the metal layers, the location of the dye in the MDM substrate and the dielectric thickness are important parameters that can be chosen to tune the color of the emission wavelength, the angle of observation, the angular divergence of the emission and the polarization of the emitted light. These features are valuable for displays and optical signage.

  18. Directional Emission from Metal-Dielectric-Metal Structures: Effect of Mixed Metal Layers, Dye Location and Dielectric Thickness

    PubMed Central

    Choudhury, Sharmistha Dutta; Badugu, Ramachandram; Ray, Krishanu; Lakowicz, Joseph R.

    2015-01-01

    Metal-dielectric-metal (MDM) structures provide directional emission close to the surface normal, which offers opportunities for new design formats in fluorescence based applications. The directional emission arises due to near-field coupling of fluorophores with the optical modes present in the MDM substrate. Reflectivity simulations and dispersion diagrams provide a basic understanding of the mode profiles and the factors that affect the coupling efficiency and the spatial distribution of the coupled emission. This work reveals that the composition of the metal layers, the location of the dye in the MDM substrate and the dielectric thickness are important parameters that can be chosen to tune the color of the emission wavelength, the angle of observation, the angular divergence of the emission and the polarization of the emitted light. These features are valuable for displays and optical signage. PMID:25844110

  19. Phytoremediation of Metal-Contaminated Soils

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shtangeeva, I.; Laiho, J.V-P.; Kahelin, H.

    2004-03-31

    Recent concerns regarding environmental contamination have necessitated the development of appropriate technologies to assess the presence and mobility of metals in soil and estimate possible ways to decrease the level of soil metal contamination. Phytoremediation is an emerging technology that may be used to cleanup contaminated soils. Successful application of phytoremediation, however, depends upon various factors that must be carefully investigated and properly considered for specific site conditions. To efficiently affect the metal removal from contaminated soils we used the ability of plants to accumulate different metals and agricultural practices to improve soil quality and enhance plant biomass. Pot experimentsmore » were conducted to study metal transport through bulk soil to the rhizosphere and stimulate transfer of the metals to be more available for plants' form. The aim of the experimental study was also to find fertilizers that could enhance uptake of metals and their removal from contaminated soil.« less

  20. Factors Affecting Smoking Tendency and Smoking Intensity

    ERIC Educational Resources Information Center

    David, Nissim Ben; Zion, Uri Ben

    2009-01-01

    Purpose: The purpose of this paper is to measure the relative effect of relevant explanatory variable on smoking tendency and smoking intensity. Design/methodology/approach: Using survey data collected by the Israeli Bureau of Statistics in 2003-2004, a probit procedure is estimated for analyzing factors that affect the probability of being a…

  1. Identification of Factors That Affect Software Complexity.

    ERIC Educational Resources Information Center

    Kaiser, Javaid

    A survey of computer scientists was conducted to identify factors that affect software complexity. A total of 160 items were selected from the literature to include in a questionnaire sent to 425 individuals who were employees of computer-related businesses in Lawrence and Kansas City. The items were grouped into nine categories called system…

  2. INTERNATIONAL DIFFERENCES IN FACTORS AFFECTING LABOUR MOBILITY.

    ERIC Educational Resources Information Center

    SELLIER, F.; ZARKA, C.

    THE GEOGRAPHICAL, OCCUPATIONAL, AND INTERFIRM MOBILITY, AND THE FACTORS AFFECTING THESE MOVEMENTS FOR WORKERS IN FRANCE, ITALY, GERMANY, AND SWEDEN IN THE PERIOD SINCE THE SECOND WORLD WAR ARE STUDIED. DATA OBTAINED FROM INDUSTRIAL SURVEYS AND GENERAL CENSUSES WERE USED TO COMPARE THE FOUR COUNTRIES WITH EACH OTHER AND WITH THE UNITED STATES.…

  3. A primer on trace metal-sediment chemistry

    USGS Publications Warehouse

    Horowitz, Arthur J.

    1985-01-01

    In most aquatic systems, concentrations of trace metals in suspended sediment and the top few centimeters of bottom sediment are far greater than concentrations of trace metals dissolved in the water column. Consequently, the distribution, transport, and availability of these constituents can not be intelligently evaluated, nor can their environmental impact be determined or predicted solely through the sampling and analysis of dissolved phases. This Primer is designed to acquaint the reader with the basic principles that govern the concentration and distribution of trace metals associated with bottom and suspended sediments. The sampling and analysis of suspended and bottom sediments are very important for monitoring studies, not only because trace metal concentrations associated with them are orders of magnitude higher than in the dissolved phase, but also because of several other factors. Riverine transport of trace metals is dominated by sediment. In addition, bottom sediments serve as a source for suspended sediment and can provide a historical record of chemical conditions. This record will help establish area baseline metal levels against which existing conditions can be compared. Many physical and chemical factors affect a sediment's capacity to collect and concentrate trace metals. The physical factors include grain size, surface area, surface charge, cation exchange capacity, composition, and so forth. Increases in metal concentrations are strongly correlated with decreasing grain size and increasing surface area, surface charge, cation exchange capacity, and increasing concentrations of iron and manganese oxides, organic matter, and clay minerals. Chemical factors are equally important, especially for differentiating between samples having similar bulk chemistries and for inferring or predicting environmental availability. Chemical factors entail phase associations (with such sedimentary components as interstitial water, sulfides, carbonates, and organic

  4. [Accumulation Characteristics and Evaluation of Heavy Metals in Soil-Crop System Affected by Wastewater Irrigation Around a Chemical Factory in Shenmu County].

    PubMed

    Qi, Yan-bing; Chu, Wan-lin; Pu, Jie; Liu, Meng-yun; Chang, Qing-rui

    2015-04-01

    Soil heavy metals Cu, Pb, Zn, and Cd, are regarded as "chemical time bombs" because of their propensity for accumulation in the soil and uptake by crops. This ultimately causes human toxicity in both the short and long-term, making farmland ecosystems dangerous to health. In this paper, accumulation and spatial variability of Cu, Zn, Pb and Cd in soil-crop system affected by wastewater irrigation around a chemical factor in northern Shaanxi province were analyzed. Results showed that wastewater irrigation around the chemical factory induced significant accumulation in soils compared with control areas. The average concentrations of available Cu and total Cu were 4.32 mg x kg(-1) and 38.4 mg x kg(-1), which were twice and 1.35 times higher than those of the control area, respectively. Soil Zn and Pb were slightly accumulated. Whereas soil Cd was significantly accumulated and was higher than the critical level of soil environmental quality (II), the available and total Cd concentrations were 0.248 mg x kg(-1) and 1.21 mg x kg(-1), which were 10 and 6.1 times higher than those of the control areas. No significant correlations were found between available and total heavy metals except between available Cd and total Cd. All the heavy metals were mainly accumulated in the top layer (0-10 cm). Spatially, soils and plants high in heavy metal concentration were distributed within the radius of about 100 m from the waste water outlet for Cu, Zn and Cd and about 200 m for Pb, and decreased exponentially with the distance from the factory. Affected by wastewater irrigation, contents of Cu, Pb and Cd in maize were 4.74, 0.129 and 0.036 mg x kg(-1) which were slightly higher than those in the control area. The content of Zn was similar to that in the control area. Affected by the vehicle exhaust, the over standard rate of Pb was 5.7% in maize. All the heavy metals did not show significant correlation between soil and crop, except Cd. The square correlation coefficients were 0

  5. Which Factors Determine Metal Accumulation in Agricultural Soils in the Severely Human-Coupled Ecosystem?

    PubMed Central

    Xu, Li; Cao, Shanshan; Wang, Jihua; Lu, Anxiang

    2016-01-01

    Agricultural soil is typically an important component of urban ecosystems, contributing directly or indirectly to the general quality of human life. To understand which factors influence metal accumulation in agricultural soils in urban ecosystems is becoming increasingly important. Land use, soil type and urbanization indicators all account for considerable differences in metal accumulation in agricultural soils, and the interactions between these factors on metal concentrations were also examined. Results showed that Zn, Cu, and Cd concentrations varied significantly among different land use types. Concentrations of all metals, except for Cd, were higher in calcareous cinnamon soil than in fluvo-aquic soil. Expansion distance and road density were adopted as urbanization indicators, and distance from the urban center was significantly negatively correlated with concentrations of Hg, and negatively correlated with concentrations of Zn, and road density was positively correlated with Cd concentrations. Multivariate analysis of variance indicated that Hg concentration was significantly influenced by the four-way interaction among all factors. The results in this study provide basic data to support the management of agricultural soils and to help policy makers to plan ahead in Beijing. PMID:27196922

  6. Which Factors Determine Metal Accumulation in Agricultural Soils in the Severely Human-Coupled Ecosystem?

    PubMed

    Xu, Li; Cao, Shanshan; Wang, Jihua; Lu, Anxiang

    2016-05-17

    Agricultural soil is typically an important component of urban ecosystems, contributing directly or indirectly to the general quality of human life. To understand which factors influence metal accumulation in agricultural soils in urban ecosystems is becoming increasingly important. Land use, soil type and urbanization indicators all account for considerable differences in metal accumulation in agricultural soils, and the interactions between these factors on metal concentrations were also examined. Results showed that Zn, Cu, and Cd concentrations varied significantly among different land use types. Concentrations of all metals, except for Cd, were higher in calcareous cinnamon soil than in fluvo-aquic soil. Expansion distance and road density were adopted as urbanization indicators, and distance from the urban center was significantly negatively correlated with concentrations of Hg, and negatively correlated with concentrations of Zn, and road density was positively correlated with Cd concentrations. Multivariate analysis of variance indicated that Hg concentration was significantly influenced by the four-way interaction among all factors. The results in this study provide basic data to support the management of agricultural soils and to help policy makers to plan ahead in Beijing.

  7. A Metasynthesis of Factors Affecting Self-Management of Chronic Illness

    PubMed Central

    SCHULMAN-GREEN, Dena; JASER, Sarah S.; PARK, Chorong; WHITTEMORE, Robin

    2015-01-01

    Aim To identify factors that may serve as facilitators and barriers to self-management described by adults living with chronic illness by conducting a qualitative metasynthesis. Background Self-management is an individuals’ active management of a chronic illness in collaboration with their family members and clinicians. Design Qualitative metasynthesis. Data Sources We analyzed studies (N=53) published between January 2000–May 2013 that described factors affecting self-management in chronic illness as reported by adults aged over 18 years with chronic illness. Review Methods Sandelowsi and Barroso approach to qualitative metasynthesis: literature search; quality appraisal; analysis; and synthesis of findings. Results Collectively, article authors reported on sixteen chronic illnesses, most commonly diabetes (N=28) and cardiovascular disease (N=20). Participants included men and women (mean age=57, range 18–94) from twenty countries representing diverse races and ethnicities. We identified five categories of factors affecting self-management: Personal/Lifestyle Characteristics; Health Status; Resources; Environmental Characteristics; and Health Care System. Factors may interact to affect self-management and may exist on a continuum of positive (facilitator) to negative (barrier). Conclusion Understanding factors that influence self-management may improve assessment of self-management among adults with chronic illness and may inform interventions tailored to meet individuals’ needs and improve health outcomes. PMID:26781649

  8. Factors affecting post-pubertal penile size in patients with hypospadias.

    PubMed

    Moriya, Kimihiko; Nakamura, Michiko; Nishimura, Yoko; Kitta, Takeya; Kanno, Yukiko; Chiba, Hiroki; Kon, Masafumi; Shinohara, Nobuo

    2016-09-01

    To evaluate actual post-pubertal penile size and factors affecting it in hypospadias patients, we retrospectively reviewed medical charts. Hypospadias patients whose external genitalia were categorized into Tanner stage 5, and whose stretched penile length was evaluated at 15 years old or older from April 2008 to April 2015, were enrolled in the present study. Stretched penile length was measured by a single examiner. Actual post-pubertal stretched penile length and factors affecting the post-pubertal stretched penile length were estimated. Statistical analysis was performed using Mann-Whitney U test and univariate and multivariate linear regression models for the determination of independent factors. Thirty patients met the inclusion criteria. Median age at evaluation was 17.2 years. Thirteen and 17 had mild and severe hypospadias, respectively. Endocrinological abnormality was identified in 5. Multivariate analysis showed that the severity of hypospadias and endocrinological abnormality were significant factors affecting stretched penile length. Stretched penile length in 25 patients without endocrinological abnormality was significantly longer than that in those with endocrinological abnormality (p = 0.036). Among patients without endocrinological abnormality, stretched penile length in 13 with severe hypospadias was significantly shorter than that in 12 with mild hypospadias (p = 0.004). While the severity of hypospadias and endocrinological abnormality at post-pubertal evaluation were factors affecting post-pubertal penile size, stretched penile length in patients with severe hypospadias was shorter even in cases without endocrinological abnormality. These results suggest that severe hypospadias is not only a disorder of urethral development, but also a disorder of penile development.

  9. Urinary heavy metal levels and relevant factors among people exposed to e-waste dismantling.

    PubMed

    Wang, Hongmei; Han, Mei; Yang, Suwen; Chen, Yanqing; Liu, Qian; Ke, Shen

    2011-01-01

    Primitive electronic waste (e-waste) recycling has become a growing environmental concern, and toxic heavy metals released from e-waste activities may continue to threaten the health of local people. To study the impact of heavy metals in people around e-waste sites, 349 people from e-waste recycling sites (exposure group) and 118 people from a green plantation (control group) were surveyed, and their urinary levels of lead (UPb), cadmium (UCd), manganese (UMn), copper (UCu), and Zinc (UZn) were assayed. Questionnaire surveys for risk factors were also performed and analyzed by using the Pearson correlation analysis. Results indicated that the levels of urinary Cd in both occupational dismantling people {GM(GSD) 0.72(0.71) ug/L} and non-occupational dismantling people {GM(GSD) 0.50(0.79) ug/L} were higher than the control group {GM(GSD) 0.27(0.85) ug/L}. Further analyses of correlations between urinary heavy metal levels and exposure factors in the exposed group revealed positive relationship between the duration of dismantling and the level of UPb (p < 0.05). Meanwhile, rice sources from local village have a positive correlation with the level of UPb and UCd (p < 0.01). Other factors, however, may also have influences on heavy metal burden, and not all urinary heavy metal levels can be contributed to e-waste dismantling exposure levels. Primitive e-waste recycling activities may contribute to the changes of urinary heavy metal levels and increase the health risk for those chronically working on e-waste dismantling. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops*

    PubMed Central

    Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar

    2007-01-01

    Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary

  11. Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops.

    PubMed

    Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar

    2007-01-01

    Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary

  12. Fluconazole affects the alkali-metal-cation homeostasis and susceptibility to cationic toxic compounds of Candida glabrata.

    PubMed

    Elicharova, Hana; Sychrova, Hana

    2014-08-01

    Candida glabrata is a salt-tolerant and fluconazole (FLC)-resistant yeast species. Here, we analyse the contribution of plasma-membrane alkali-metal-cation exporters, a cation/proton antiporter and a cation ATPase to cation homeostasis and the maintenance of membrane potential (ΔΨ). Using a series of single and double mutants lacking CNH1 and/or ENA1 genes we show that the inability to export potassium and toxic alkali-metal cations leads to a slight hyperpolarization of the plasma membrane of C. glabrata cells; this hyperpolarization drives more cations into the cells and affects cation homeostasis. Surprisingly, a much higher hyperpolarization of C. glabrata plasma membrane was produced by incubating cells with subinhibitory concentrations of FLC. FLC treatment resulted in a substantially increased sensitivity of cells to various cationic drugs and toxic cations that are driven into the cell by negative-inside plasma-membrane potential. The effect of the combination of FLC plus cationic drug treatment was enhanced by the malfunction of alkali-metal-cation transporters that contribute to the regulation of membrane potential and cation homeostasis. In summary, we show that the combination of subinhibitory concentrations of FLC and cationic drugs strongly affects the growth of C. glabrata cells. © 2014 The Authors.

  13. Factors affecting rotator cuff healing.

    PubMed

    Mall, Nathan A; Tanaka, Miho J; Choi, Luke S; Paletta, George A

    2014-05-07

    Several studies have noted that increasing age is a significant factor for diminished rotator cuff healing, while biomechanical studies have suggested the reason for this may be an inferior healing environment in older patients. Larger tears and fatty infiltration or atrophy negatively affect rotator cuff healing. Arthroscopic rotator cuff repair, double-row repairs, performing a concomitant acromioplasty, and the use of platelet-rich plasma (PRP) do not demonstrate an improvement in structural healing over mini-open rotator cuff repairs, single-row repairs, not performing an acromioplasty, or not using PRP. There is conflicting evidence to support postoperative rehabilitation protocols using early motion over immobilization following rotator cuff repair.

  14. Factors affecting corticosteroid concentrations in yellow-bellied marmots.

    PubMed

    Armitage, K B

    1991-01-01

    1. Bound and total corticosteroid concentrations of yellow-bellied marmots (Marmota flaviventris) were lowest in May after emergence from hibernation and peaked in August prior to immergence. 2. Total corticosteroids were affected by age but not by sex or reproductive status. 3. There was no consistent relationship between measures of population density and concentrations of corticosteroids; when a significant relationship occurred, only 22-34% of the variation was explained. 4. Social status and social behavior were the major factors affecting corticosteroid concentrations.

  15. Factors affecting Iran`s future. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sinai, J.

    1993-05-28

    This study examines the factors affecting Iran`s future by focusing on the demographic, economic, and military trends in Iran and their impact on the country`s national security objectives in the next decade. The paper also assesses the implications of an economic embargo on Iran and potential Iranian threats to regional and United States national interests.

  16. Are Affective Factors a Good Predictor of Science Achievement? Examining the Role of Affective Factors Based on PISA 2006

    ERIC Educational Resources Information Center

    Ozel, Murat; Caglak, Serdar; Erdogan, Mehmet

    2013-01-01

    This study investigated how affective factors like attitude and motivation contribute to science achievement in PISA 2006 using linear structural modeling. The data set of PISA 2006 collected from 4942 fifteen-year-old Turkish students (2290 females, 2652 males) was used for the statistical analyses. A total of 42 selected items on a four point…

  17. Insufficient acetabular version increases blood metal ion levels after metal-on-metal hip resurfacing.

    PubMed

    Hart, Alister J; Skinner, John A; Henckel, Johann; Sampson, Barry; Gordon, Fabiana

    2011-09-01

    Many factors affect the blood metal ion levels after metal-on-metal (MOM) hip arthroplasty. The main surgically adjustable variable is the amount of coverage of the head provided by the cup which is a function of the inclination and version angles. However, most studies have used plain radiographs which have questionable precision and accuracy, particularly for version and large diameter metal heads; further, these studies do not simultaneously assess version and inclination. Thus the relationship between version and blood metal ions levels has not been resolved. We determined whether cup inclination and version influence blood metal ion levels while adjusting for age at assessment, gender, body mass index, horizontal femoral offset, head size, manufacturer hip type, and Oxford hip score. We prospectively followed 100 individuals (51 females, 49 males) with unilateral MOM hip resurfacing who underwent clinical assessment, CT scanning, and blood metal ion measurement. Multiple regression analysis was used to determine which variables were predictors of blood metal ion levels and to model the effect of these variables. Only cup inclination, version angles, and gender influenced blood cobalt or chromium levels. Cobalt and chromium levels positively correlated with inclination angle and negatively correlated with version angle. The effect of changes in version angle was less than for inclination angle. Based on our observations, we developed a formula to predict the effect of these parameters on metal ion levels. Our data suggest insufficient cup version can cause high blood metal ions after MOM hip arthroplasty. We were unable to show that excessive version caused high levels. Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

  18. Multiple factors impact the contents of heavy metals in vegetables in high natural background area of China.

    PubMed

    Gan, Yandong; Wang, Lihong; Yang, Guiqiang; Dai, Jiulan; Wang, Renqing; Wang, Wenxing

    2017-10-01

    A field survey was conducted to investigate the concentrations of chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb) in vegetables, corresponding cultivated soils and irrigation waters from 36 open sites in high natural background area of Wuzhou, South China. Redundancy analysis, Spearman's rho correlation analysis and multiple regression analysis were adopted to evaluate the contributions of impacting factors on metal contents in the edible parts of vegetables. This study concluded that leafy and root vegetables had relatively higher metal concentrations and adjusted transfer factor values compared to fruiting vegetables according to nonparametric tests. Plant species, total soil metal content and soil pH value were affirmed as three critical factors with the highest contribution rate among all the influencing factors. The bivariate curve equation models for heavy metals in the edible vegetable tissues were well fitted to predict the metal concentrations in vegetables. The results from this case study also suggested that it could be one of efficient strategies for clean agricultural production and food safety in high natural background area to breed vegetable varieties with low heavy metal accumulation and to enlarge planting scale of these varieties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Factors affecting cardiac rehabilitation referral by physician specialty.

    PubMed

    Grace, Sherry L; Grewal, Keerat; Stewart, Donna E

    2008-01-01

    Cardiac rehabilitation (CR) is widely underutilized because of multiple factors including physician referral practices. Previous research has shown CR referral varies by type of provider, with cardiologists more likely to refer than primary care physicians. The objective of this study was to compare factors affecting CR referral in primary care physicians versus cardiac specialists. A cross-sectional survey of a stratified random sample of 510 primary care physicians and cardiac specialists (cardiologists or cardiovascular surgeons) in Ontario identified through the Canadian Medical Directory Online was administered. One hundred four primary care physicians and 81 cardiac specialists responded to the 26-item investigator-generated survey examining medical, demographic, attitudinal, and health system factors affecting CR referral. Primary care physicians were more likely to endorse lack of familiarity with CR site locations (P < .001), lack of standardized referral forms (P < .001), inconvenience (P = .04), program quality (P = .004), and lack of discharge communication from CR (P = .001) as factors negatively impacting CR referral practices than cardiac specialists. Cardiac specialists were significantly more likely to perceive that their colleagues and department would regularly refer patients to CR than primary care physicians (P < .001). Where differences emerged, primary care physicians were more likely to perceive factors that would impede CR referral, some of which are modifiable. Marketing CR site locations, provision of standardized referral forms, and ensuring discharge summaries are communicated to primary care physicians may improve their willingness to refer to CR.

  20. Size versus electronic factors in transition metal carbide and TCP phase stability

    NASA Astrophysics Data System (ADS)

    Pettifor, D. G.; Seiser, B.; Margine, E. R.; Kolmogorov, A. N.; Drautz, R.

    2013-09-01

    The contributions of atomic size and electronic factors to the structural stability of transition metal carbides and topologically close-packed (TCP) phases are investigated. The hard-sphere model that has been used by Cottrell to rationalize the occurrence of the octahedral and trigonal local coordination polyhedra within the transition metal carbides is shown to have limitations in TiC since density functional theory (DFT) predicts that the second most metastable phase closest to the B1 (NaCl) ground state takes the B? (BN) structure type with 5-atom local coordination polyhedra with very short Ti-C bond lengths. The importance of electronic factors in the TCP phases is demonstrated by DFT predictions that the A15, ? and ? phases are stabilized between groups VI and VII of the elemental transition metals, whereas the ? and Laves phases are destabilized. The origin of this difference is related to the bimodal shape parameter of the electronic density of states by using the bond-order potential expansion of the structural energy within a canonical tight-binding model. The importance of the size factor in the TCP phases is illustrated by the DFT heats of formation for the binary systems Mo-Re, Mo-Ru, Nb-Re and Nb-Ru which show that the ? and Laves phases become more and more stable compared to A15, ? and ? as the size factor increases from Mo-Re through to Nb-Ru.

  1. Metals other than uranium affected microbial community composition in a historical uranium-mining site.

    PubMed

    Sitte, Jana; Löffler, Sylvia; Burkhardt, Eva-Maria; Goldfarb, Katherine C; Büchel, Georg; Hazen, Terry C; Küsel, Kirsten

    2015-12-01

    To understand the links between the long-term impact of uranium and other metals on microbial community composition, ground- and surface water-influenced soils varying greatly in uranium and metal concentrations were investigated at the former uranium-mining district in Ronneburg, Germany. A soil-based 16S PhyloChip approach revealed 2358 bacterial and 35 archaeal operational taxonomic units (OTU) within diverse phylogenetic groups with higher OTU numbers than at other uranium-contaminated sites, e.g., at Oak Ridge. Iron- and sulfate-reducing bacteria (FeRB and SRB), which have the potential to attenuate uranium and other metals by the enzymatic and/or abiotic reduction of metal ions, were found at all sites. Although soil concentrations of solid-phase uranium were high, ranging from 5 to 1569 μg·g (dry weight) soil(-1), redundancy analysis (RDA) and forward selection indicated that neither total nor bio-available uranium concentrations contributed significantly to the observed OTU distribution. Instead, microbial community composition appeared to be influenced more by redox potential. Bacterial communities were also influenced by bio-available manganese and total cobalt and cadmium concentrations. Bio-available cadmium impacted FeRB distribution while bio-available manganese and copper as well as solid-phase zinc concentrations in the soil affected SRB composition. Archaeal communities were influenced by the bio-available lead as well as total zinc and cobalt concentrations. These results suggest that (i) microbial richness was not impacted by heavy metals and radionuclides and that (ii) redox potential and secondary metal contaminants had the strongest effect on microbial community composition, as opposed to uranium, the primary source of contamination.

  2. Metal-resistant rhizobacteria isolates improve Mucuna deeringiana phytoextraction capacity in multi-metal contaminated soils from a gold mining area.

    PubMed

    Boechat, Cácio Luiz; Giovanella, Patricia; Amorim, Magno Batista; de Sá, Enilson Luiz Saccol; de Oliveira Camargo, Flávio Anastácio

    2017-01-01

    Phytoremediation consists of biological techniques for heavy metal remediation, which include exploring the genetic package of vegetable species to remove heavy metals from the environment. The goals of this study were to investigate heavy metal and bioaugmentation effects on growth and nutrient uptake by Mucuna deeringiana; to determine the metal translocation factor and bioconcentration factor and provide insight for using native bacteria to enhance heavy metal accumulation. The experiment was conducted under greenhouse conditions using a 2 × 4 factorial scheme with highly and slightly contaminated soil samples and inoculating M. deeringiana with three highly lead (Pb +2 )-resistant bacteria Kluyvera intermedia (Ki), Klebsiella oxytoca (Ko), and Citrobacter murliniae (Cm) isolated from the rhizosphere of native plants identified as Senecio brasiliensis (Spreng.) Less., Senecio leptolobus DC., and Baccharis trimera (Less) DC., respectively. The increased heavy metal concentrations in soil samples do not decrease the root dry mass of M. deeringiana, concerning the number and dry weight of nodules. The shoot dry mass is reduced by the increasing concentration of heavy metals in soil associated with Kluyvera intermedia and Klebsiella oxytoca bacteria. The number of nodules is affected by heavy metals associated with Citrobacter murliniae bacteria. The bacteria K. intermedia, C. murliniae, and K. oxytoca increase the lead and cadmium available in the soil and enhanced metal uptake by Mucuna deeringiana. The M. deeringiana specie has characteristics that make it hyperaccumulate copper and zinc. The translocation and bioconcentration factors for M. deeringiana characterize it as a promising candidate to phytostabilize multi-metal contaminated soils.

  3. Factors Affecting Radiologist's PACS Usage.

    PubMed

    Forsberg, Daniel; Rosipko, Beverly; Sunshine, Jeffrey L

    2016-12-01

    The purpose of this study was to determine if any of the factors radiologist, examination category, time of week, and week effect PACS usage, with PACS usage defined as the sequential order of computer commands issued by a radiologist in a PACS during interpretation and dictation. We initially hypothesized that only radiologist and examination category would have significant effects on PACS usage. Command logs covering 8 weeks of PACS usage were analyzed. For each command trace (describing performed activities of an attending radiologist interpreting a single examination), the PACS usage variables number of commands, number of command classes, bigram repetitiveness, and time to read were extracted. Generalized linear models were used to determine the significance of the factors on the PACS usage variables. The statistical results confirmed the initial hypothesis that radiologist and examination category affect PACS usage and that the factors week and time of week to a large extent have no significant effect. As such, this work provides direction for continued efforts to analyze system data to better understand PACS utilization, which in turn can provide input to enable optimal utilization and configuration of corresponding systems. These continued efforts were, in this work, exemplified by a more detailed analysis using PACS usage profiles, which revealed insights directly applicable to improve PACS utilization through modified system configuration.

  4. Cognitive Factors Affecting Freeze-like Behavior in Humans.

    PubMed

    Alban, Michael W; Pocknell, Victoria

    2017-01-01

    Contemporary research on survival-related defensive behaviors has identified physiological markers of freeze/flight/fight. Our research focused on cognitive factors associated with freeze-like behavior in humans. Study 1 tested if an explicit decision to freeze is associated with the psychophysiological state of freezing. Heart rate deceleration occurred when participants chose to freeze. Study 2 varied the efficacy of freezing relative to other defense options and found "freeze" was responsive to variations in the perceived effectiveness of alternative actions. Study 3 tested if individual differences in motivational orientation affect preference for a "freeze" option when the efficacy of options is held constant. A trend in the predicted direction suggested that naturally occurring cognitions led loss-avoiders to select "freeze" more often than reward-seekers. In combination, our attention to the cognitive factors affecting freeze-like behavior in humans represents a preliminary step in addressing an important but neglected research area.

  5. Factors affecting the use of hardwood flooring in urban rehabilitation

    Treesearch

    Robert L. Jr. Nevel; Robert L. Jr. Nevel

    1973-01-01

    The continued use of hardwood flooring in urban rehabilitation is being threatened. A study of the influences that determine the choice of flooring indicates that economic, physical, or technological factors dominate. Most factors affecting the use of hardwood flooring are related to cost, availability, and compatibility. Of these factors, time and cost of installation...

  6. Environmental factors affecting soil metals near outlet roads in Poznań, Poland: impact of grain size, soil depth, and wind dispersal.

    PubMed

    Ciazela, Jakub; Siepak, Marcin

    2016-06-01

    We determined the Cd, Cr, Cu, Ni, Pb, and Zn concentrations in soil samples collected along the eight main outlet roads of Poznań. Samples were collected at distances of 1, 5, and 10 m from the roadway edges at depth intervals of 0-20 and 40-60 cm. The metal content was determined in seven grain size fractions. The highest metal concentrations were observed in the smallest fraction (<0.063 mm), which were up to four times higher than those in sand fractions. Soil Pb, Cu, and Zn (and to a lesser extent Ni, Cr, and Cd) all increased in relation to the geochemical background. At most sampling sites, metal concentrations decreased with increasing distance from roadway edges and increasing depth. In some locations, the accumulation of metals in soils appears to be strongly influenced by wind direction. Our survey findings should contribute in predicting the behavior of metals along outlet road, which is important by assessing sources for further migration of heavy metals into the groundwater, plants, and humans.

  7. Factors Affecting Sleep Quality of Patients in Intensive Care Unit

    PubMed Central

    Bihari, Shailesh; Doug McEvoy, R.; Matheson, Elisha; Kim, Susan; Woodman, Richard J.; Bersten, Andrew D.

    2012-01-01

    Introduction: Sleep disturbance is a frequently overlooked complication of intensive care unit (ICU) stay. Aim: To evaluate sleep quality among patients admitted to ICU and investigate environmental and non-environmental factors that affect sleep quality in ICU. Methods: Over a 22-month period, we consecutively recruited patients who spent ≥ 2 nights post-endotracheal extubation in ICU and who were orientated to time, place, and person on the day of discharge. Self-reported sleep quality, according to a modified Freedman questionnaire, which provided data on self-reported ICU sleep quality in ICU and environmental factors affecting sleep quality in the ICU, were collected. We also investigated non-environmental factors, such as severity of illness, ICU interventions, and medications that can affect sleep quality. Results: Fifty males and 50 females were recruited with a mean (± SD) age of 65.1 ± 15.2 years. APACHE II score at admission to ICU was 18.1 ± 7.5 with duration of stay 6.7 ± 6.5days. Self-reported sleep quality score at home (1 = worst; 10 = best) was 7.0 ± 2.2; this decreased to 4.0 ± 1.7 during their stay in ICU (p < 0.001). In multivariate analysis with APACHE III as severity of illness (R2 = 0.25), factors [exp(b)(95% CI), p value] which significantly affected sleep in ICU were sex [0.37(0.19-0.72), p < 0.01], age and sex interaction [1.02(1.01-1.03), p < 0.01], bedside phone [0.92(0.87-0.97), p < 0.01], prior quality of sleep at home [1.30(1.05-1.62), p = 0.02], and use of steroids [0.82(0.69-0.98), p = 0.03] during the stay in ICU. Conclusion: Reduced sleep quality is a common problem in ICU with a multifactorial etiology. Citation: Bihari S; McEvoy RD; Kim S; Woodman RJ; Bersten AD. Factors affecting sleep quality of patients in intensive care unit. J Clin Sleep Med 2012;8(3):301-307. PMID:22701388

  8. An Analysis of Factors That Affect the Educational Performance of Agricultural Students

    ERIC Educational Resources Information Center

    Greenway, Gina

    2012-01-01

    Many factors contribute to student achievement. This study focuses on three areas: how students learn, how student personality type affects performance, and how course format affects performance outcomes. The analysis sought to improve understanding of the direction and magnitude with which each of these factors impacts student success. Improved…

  9. Assessment of Factor Affecting Institutional Performance: The Case of Wolaita Sodo University

    ERIC Educational Resources Information Center

    Shibru, Sintayehu; Bibiso, Mesfin; Ousman, Kedir

    2017-01-01

    The purpose of this study is to explore factors that affect institutional performance of Wolaita Sodo University. The study has identified middle level manager's perceptions toward institutional performance to indicate the key factors that seem to affect the performance of the university. Data were collected using structured questionnaires and…

  10. Trace metal accumulation in soil and their phytoavailability as affected by greenhouse types in north China.

    PubMed

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Hickethier, Martina; Hu, Wenyou

    2015-05-01

    Long-term heavy organic fertilizer application has linked greenhouse vegetable production (GVP) with trace metal contamination in north China. Given that trace metals release from fertilizers and their availability may be affected by discrepant environmental conditions, especially temperature under different greenhouses, this study investigated Cd, Cu, Pb, and Zn accumulation and contamination extent in soil as well as their phytoavailability under two major greenhouses in Tongshan, north China, namely solar greenhouse (SG) and round-arched plastic greenhouse (RAPG), to evaluate their presumed difference. The results showed significant Cd, Cu, Pb, and Zn accumulation in GVP soil by comparing with those in open-field soil, but their accumulation extent and rates were generally greater in SG than those in RAPG. This may be related to more release of trace metals to soil due to the acceleration of decomposition and humification process of organic fertilizers under higher soil temperature in SG relative to that in RAPG. Overall, soil in both greenhouses was generally less polluted or moderately polluted by the study metals. Similarly, decreased soil pH and elevated soil available metals in SG caused higher trace metals in leaf vegetables in SG than those in RAPG, although there was no obvious risk via vegetable consumption under both greenhouses. Lower soil pH may be predominantly ascribed to more intensive farming practices in SG while elevated soil available metals may be attributed to more release of dissolved organic matter-metal complexes from soil under higher temperature in SG. The data provided in this study may assist in developing reasonable and sustainable fertilization strategies to abate trace metal contamination in both greenhouses.

  11. How do low doses of desferrioxamine B and EDTA affect the phytoextraction of metals in sunflower?

    PubMed

    Cornu, J Y; Dépernet, C; Garnier, C; Lenoble, V; Braud, A; Lebeau, T

    2017-08-15

    The aim of this study was to compare the efficiency of siderophore desferrioxamine B (DFOB) and EDTA in increasing the phytoextraction of metals in sunflower. A 28-day pot experiment was conducted in a metal-contaminated soil supplied with 200μmolkg -1 of DFOB or EDTA. Pore water was collected and pseudo-polarographic analyses were conducted to assess the impact of the two chelators on the mobility and speciation of metals in the liquid phase. Our results showed that DFOB is not an efficient mobilizing agent of divalent metals in soil. Adding DFOB selectively increased the mobility of trivalent metals while the supply of EDTA simultaneously increased the mobility of both trivalent and divalent metals. EDTA significantly reduced the labile fractions of Cd, Cu, (Pb) and Zn measured in the porewater. The labile concentration of Cd and Zn measured in presence of EDTA was even less than that measured in the control. As expected from the pore water analysis, the addition of DFOB did not affect the phytoextraction of any divalent metals. In contrast, the addition of EDTA enhanced Cu and Ni phytoextraction in sunflower 2.0 to 2.8 fold for Cu and 1.3 to 2.3 fold for Ni, depending on the cultivar. This result supports different hypotheses regarding the forms and the related pathways in which metals are taken up in presence of EDTA. Based on the results obtained for Ni, whose uptake is rate limited by its internalization across the cell membrane, the direct uptake of metal-EDTA complexes via the non-selective apoplastic pathway is hypothesized to contribute the most to the overall uptake of metals in presence of EDTA, even added at "low" concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Factors affecting onset of puberty in Denizli province in Turkey.

    PubMed

    Semiz, Serap; Kurt, Funda; Kurt, Devrim Tanil; Zencir, Mehmet; Sevinç, Ozgür

    2009-01-01

    The relationship between the possible factors affecting pubertal onset and pubertal timing was investigated in the Denizli province in Turkey. A total number of 3311 subjects (1562 girls, 1749 boys) aged 6-16.5 years participated in this study. Body mass index (BMI) was calculated. Pubertal stages were assessed according to methods of Marshall and Tanner. Testicular volume was determined using Prader orchidometer. Menarcheal age was recorded. All parents and students completed different questionnaires on demographic variables affecting pubertal timing such as socioeconomic conditions, psychosocial factors, exercise, nutritional status, chronic diseases, migration and birth weight. Using distribution percentiles of pubertal stages according to age, the relation between pubertal timing and factors affecting puberty was investigated. There was no significant association between exercise, birth weight, migration, chronic disease, and socioeconomic status and age of puberty onset. Menarcheal age of overweight and obese girls was significantly lower than that of girls with normal weight. In-family stress was the cause of early puberty in girls and of delayed puberty in boys.

  13. Accumulation of trace metals in sediments in a Mediterranean Lagoon: Usefulness of metal sediment fractionation and elutriate toxicity assessment.

    PubMed

    Zaaboub, Noureddine; Martins, Maria Virgínia Alves; Dhib, Amel; Béjaoui, Béchir; Galgani, François; El Bour, Monia; Aleya, Lotfi

    2015-12-01

    The authors investigated sediment quality in Bizerte Lagoon (Tunisia) focusing on geochemical characteristics, metal sediment fractionation and elutriate toxicity assessment. Nickel, Cu, Zn, Pb, Cr and Cd partitioning in sediments was studied; accumulation and bioavailability were elucidated using enrichment factors, sequential extractions, redox potential, acid volatile sulfide and biotest procedures in toxicity evaluation. Results revealed an accumulation for Pb and Zn, reaching 99 and 460 mg kg(-1) respectively. In addition, the acid volatile sulfide values were high in both eastern and western lagoon areas, thus affecting metal availability. Mean enrichment factor values for Pb and Zn were 4.8 and 4.9, respectively, with these elements as the main contributors to the lagoon's moderate enrichment level. Toxicity levels were influenced by accumulation of Zn in different surface sediment areas. Core sediments were investigated in areas with the highest metal concentrations; metal fractionation and biotest confirmed that Zn contributes to sediment toxicity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Thermal and Compositional Variation of Glassy Metal Structure Factors.

    NASA Astrophysics Data System (ADS)

    From, Milton

    The x-ray total structure factor of the glassy -metal alloys Mg_{70}Zn_ {30}, Ca_{70}Mg_{30 } and Mg_{85.5}Cu _{14.5} has been measured at three temperatures: 9K, 150K, and 300K. The data have a statistical precision of about.8% and an absolute accuracy of roughly 3%. Percus-Yevick hard sphere structure factors may be fitted quite accurately to the data in the region of the first peak. In addition, the variation of the experimental structure factor with composition is found to be consistent with the Percus-Yevick theory. At low k values, Percus -Yevick and other theoretical model structure factors are in poor agreement with the data. Within experimental error, the temperature dependence of the structure factors is in agreement with the Debye plane wave phonon model of atomic vibrations. The measured structure factors are used to calculate the electrical resistivity from the Faber-Ziman equation. In most cases, the calculations yield both the correct magnitude of resistivity and sign of the temperature coefficient of resistivity.

  15. Factors affecting the periapical healing process of endodontically treated teeth.

    PubMed

    Holland, Roberto; Gomes, João Eduardo; Cintra, Luciano Tavares Angelo; Queiroz, Índia Olinta de Azevedo; Estrela, Carlos

    2017-01-01

    Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction.

  16. Nurse aide decision making in nursing homes: factors affecting empowerment.

    PubMed

    Chaudhuri, Tanni; Yeatts, Dale E; Cready, Cynthia M

    2013-09-01

    To evaluate factors affecting structural empowerment among nurse aides in nursing homes. Structural empowerment can be defined as the actual rather than perceived ability to make autonomous decisions within an organisation. Given the paucity of research on the subject, this study helps to close the gap by identifying factors that affect nurse aide empowerment, that is, decision-making among nurse aides. The data for the study come from self-administered questionnaires distributed to direct-care workers (nurse aides) in 11 nursing homes in a southern state in the USA. Ordinary least square regression models were estimated to analyse the effects of demographic predictors, personal factors (competency, emotional exhaustion and positive attitude) and structural characteristics (coworker and supervisor support, information availability and shared governance) on nurse aide decision-making. Findings suggest race among demographic predictors, emotional exhaustion among personal characteristics, and supervisor support, and shared governance among structural factors, significantly affect nurse aide decision-making. It is important to explore race as one of the central determinants of structural empowerment among nurse aides. In addition, the nature and type of emotional exhaustion that propels decision-making needs to be further examined. The study shows the importance of shared governance and supervisor support for fostering nurse aide empowerment. © 2013 Blackwell Publishing Ltd.

  17. Nutritional Factors Affecting Adult Neurogenesis and Cognitive Function

    USDA-ARS?s Scientific Manuscript database

    Adult neurogenesis, a complex process by which stem cells in the hippocampal brain region differentiate and proliferate into new neurons and other resident brain cells, is known to be affected by many intrinsic and extrinsic factors, including diet. Neurogenesis plays a critical role in neural plas...

  18. Temporal-spatial variation and partitioning of dissolved and particulate heavy metal(loid)s in a river affected by mining activities in Southern China.

    PubMed

    Wang, Juan; Liu, Guannan; Wu, Hao; Zhang, Tao; Liu, Xinhui; Li, Wuqing

    2018-04-01

    The physicochemical properties and heavy metal(loid) concentrations of the river water both fluctuate greatly along the river affected by mining activities, and the transportation of heavy metal(loid)s is therefore more complicated than unpolluted river. Dissolved and particulate heavy metal(loid)s in a river polluted by mining activities were measured to study their temporal-spatial variation and partitioning. The concentrations of dissolved arsenic (As), cadmium (Cd), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were considerably high at the sites near the mine area. Notably, dissolved As at most sites were higher than the Chinese quality criterion of class II for surface water indicating high environmental risk. Mn and Pb at most sites and Ni at a part of the sites mainly existed in the particulate phase. For other heavy metal(loid)s, i.e., As, Cd, chromium (Cr), and Zn, the particulate phase was extremely high at the sites near the mine area and responsible for heavy metal(loid) transport. Significant correlations between particulate heavy metal(loid)s and temperature and electrical conductivity (EC) were found. However, the partitioning of heavy metal(loid)s did not significantly relate to the river water properties, due to most heavy metal(loid)s in suspended particulate matter (SPM) are stable and affected less by water properties. Except for Cr and Ni, other heavy metal(loid)s showed high concentrations in sediments, and considerable Cd, Mn, and Zn existed in exchangeable and carbonate fraction indicating high environmental risk. The environmental assessment of SPM showed that Cd, Zn, and As, as the main pollutants in SPM, all reached extremely polluted level at the sites near the mine area, and the environmental risk of heavy metal(loid)s in SPM was higher during dry season than that during wet season. The results can contribute to understanding the partitioning and transportation of heavy metal(loid)s in the river affected by mining activities.

  19. The key factors affecting students' individual interest in school science lessons

    NASA Astrophysics Data System (ADS)

    Cheung, Derek

    2018-01-01

    Individual interest in school science lessons can be defined as a relatively stable and enduring personal emotion comprising affective and behavioural reactions to events in the regular science lessons at school. Little research has compared the importance of different factors affecting students' individual interest in school science lessons. The present study aimed to address this gap, using a mixed methods design. Qualitative interview data were collected from 60 Hong Kong junior secondary school students, who were asked to describe the nature of their interest in science lessons and the factors to which they attribute this. Teacher interviews, parent interviews, and classroom observations were conducted to triangulate student interview data. Five factors affecting students' individual interest in school science lessons were identified: situational influences in science lessons, individual interest in science, science self-concept, grade level, and gender. Quantitative data were then collected from 591 students using a questionnaire. Structural equation modelling was applied to test a hypothesised model, which provided an acceptable fit to the student data. The strongest factor affecting students' individual interest in school science lessons was science self-concept, followed by individual interest in science and situational influences in science lessons. Grade level and gender were found to be nonsignificant factors. These findings suggest that teachers should pay special attention to the association between academic self-concept and interest if they want to motivate students to learn science at school.

  20. Metabolic Factors Affecting Enhanced Phosphorus Uptake by Activated Sludge

    PubMed Central

    Boughton, William H.; Gottfried, Richard J.; Sinclair, Norval A.; Yall, Irving

    1971-01-01

    Activated sludges obtained from the Rilling Road plant located at San Antonio, Tex., and from the Hyperion treatment plant located at Los Angeles, Calif., have the ability to remove all of the orthophosphate normally present in Tucson sewage within 3 hr after being added to the waste water. Phosphorus removal was independent of externally supplied sources of energy and ions, since orthophosphate and 32P radioactivity were readily removed from tap water, glass-distilled water, and deionized water. Phosphorus uptake by Rilling sludge in the laboratory appears to be wholly biological, as it has an optimum pH range (7.7 to 9.7) and an optimum temperature range (24 to 37 C). It was inhibited by HgCl2, iodoacetic acid, p-chloromercuribenzoic acid, NaN3, and 2, 4-dinitrophenol (compounds that affect bacterial membrane permeability, sulfhydryl enzymes, and adenosine triphosphate synthesis). Uptake was inhibited by 1% NaCl but was not affected by 10−3m ethylenediaminetetraacetic acid disodium salt (a chelating agent for many metallic ions). PMID:5002140

  1. Anomalous shear band characteristics and extra-deep shock-affected zone in Zr-based bulk metallic glass treated with nanosecond laser peening.

    PubMed

    Wei, Yanpeng; Xu, Guangyue; Zhang, Kun; Yang, Zhe; Guo, Yacong; Huang, Chenguang; Wei, Bingchen

    2017-03-07

    The effects of nanosecond laser peening on Zr 41 Ti 14 Cu 12.5 Ni 10 Be 22.5 metallic glass were investigated in this study. The peening treatment produced an extra-deep shock-affected zone compared to crystal metal. As opposed to the conventional shear bands, numerous arc shear bands appeared and aggregated in the vertical direction of the laser beam, forming basic units for accommodating plastic deformation. The arc shear bands exhibited short and discrete features near the surface of the material, then grew longer and fewer at deeper peened layer depths, which was closely related to the laser shock wave attenuation. An energy dissipation model was established based on Hugoniot Elastic Limit and shear band characteristics to represent the formation of an extra-deep shock-affected zone. The results presented here suggest that the bulk modification of metallic glass with a considerable affected depth is feasible. Further, they reveal that nanosecond laser peening is promising as an effective approach to tuning shear bands for improved MGs ductility.

  2. 75 FR 80114 - Agency Information Collection (Obligation To Report Factors Affecting Entitlement) Activity Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-21

    ... (Obligation To Report Factors Affecting Entitlement) Activity Under OMB Review AGENCY: Veterans Benefits... Report Factors Affecting Entitlement (38 CFR 3.204(a)(1), 38 CFR 3.256(a) and 38 CFR 3.277(b)). OMB... benefits must report changes in their entitlement factors. Individual factors such as income, marital...

  3. Factors Affecting Students' Grades in Principles of Economics

    ERIC Educational Resources Information Center

    Kara, Orhan; Bagheri, Fathollah; Tolin, Thomas

    2009-01-01

    Factors affecting students' grades in principles of microeconomics and macroeconomics students are analyzed from the data collected in two public universities. Results indicate that gender, number of hours worked, SAT scores, number of missed classes, recommending the course to a friend, instructors, being a junior, number of economics courses…

  4. Partitioning and bioaccumulation of metals from oil sands process affected water in indigenous Parachlorella kessleri.

    PubMed

    Mahdavi, Hamed; Liu, Yang; Ulrich, Ania C

    2013-02-01

    This paper studies the partitioning and bioaccumulation of ten target metals ((53)Cr, Mn, Co, (60)Ni, (65)Cu, (66)Zn, As, (88)Sr, (95)Mo and Ba) from oil sands tailings pond water (TPW) by indigenous Parachlorella kessleri. To determine the role of extracellular and intracellular bioaccumulation in metal removal by P. kessleri, TPW samples taken from two oil sands operators (Syncrude Canada Ltd. and Albian Sands Energy Inc.) were enriched with nutrient supplements. Results indicate that intracellular bioaccumulation played the main role in metal removal from TPW; whereas extracellular bioaccumulation was only observed to some extent for Mn, Co, (60)Ni, (65)Cu, (88)Sr, (95)Mo and Ba. The FTIR scan and titration of functional groups on the cell surface indicated low metal binding capacity by indigenous P. kessleri. However, it is believed that the dissolved cations and organic ligand content in TPW (such as naphthenic acids) may interfere with metal binding on the cell surface and lower extracellular bioaccumulation. In addition, the total bioaccumulation and bioconcentration factor (BCF) varied during the cultivation period in different growth regimes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Systematic review of factors affecting pharmaceutical expenditures.

    PubMed

    Mousnad, Mohamed Awad; Shafie, Asrul Akmal; Ibrahim, Mohamed Izham

    2014-06-01

    To systematically identify the main factors contributing to the increase in pharmaceutical expenditures. A systematic search of published studies was conducted utilising major widely used electronic databases using the search terms 'factors,' 'financing,' 'pharmaceutical,' and 'expenditures.' To be included, the studies needed to: (1) measure at least one of the following outcomes: total growth in pharmaceutical expenditures, price growth or quantity growth; (2) mention a clear method for analysing the impact of factors affecting the increases in drug expenditures; (3) be written in English. Nonprimary articles that were published only as an abstract, a review, a commentary or a letter were excluded. From a total of 2039 studies, only 25 were included in the full review. The main determinant categories that were identified in the review were factors related to price, utilisation, therapeutic choice, demand and health care system. The major cost drivers were found to be changes in drug quantities and therapies as well as new drugs. It is important for policymakers to understand pharmaceutical spending trends and the factors that influence them in order to formulate effective cost containment strategies and design optimum drug policy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Effect of the edaphic factors and metal content in soil on the diversity of Trichoderma spp.

    PubMed

    Racić, Gordana; Körmöczi, Péter; Kredics, László; Raičević, Vera; Mutavdžić, Beba; Vrvić, Miroslav M; Panković, Dejana

    2017-02-01

    Influence of edaphic factors and metal content on diversity of Trichoderma species at 14 different soil sampling locations, on two depths, was examined. Forty-one Trichoderma isolates from 14 sampling sites were determined as nine species based on their internal transcribed spacer (ITS) sequences. Our results indicate that weakly alkaline soils are rich sources of Trichoderma strains. Also, higher contents of available K and P are connected with higher Trichoderma diversity. Increased metal content in soil was not inhibiting factor for Trichoderma species occurrence. Relationship between these factors was confirmed by locally weighted sequential smoothing (LOESS) nonparametric smoothing analysis. Trichoderma strain (Szeged Microbiology Collection (SZMC) 22669) from soil with concentrations of Cr and Ni above remediation values should be tested for its potential for bioremediation of these metals in polluted soils.

  7. Key factors affecting dying children and their families.

    PubMed

    Hinds, Pamela S; Schum, Lisa; Baker, Justin N; Wolfe, Joanne

    2005-01-01

    The death of a child alters the life and health of others immediately and for the rest of their lives. How a child dies influences parents' abilities to continue their role functions as well as siblings' abilities to make and maintain friendships, and may be the basis for health care providers' decisions to exit direct care roles. Thus, facilitating a "good death"-an obvious care priority for all involved with the dying child-ought also to be a priority for the health of bereaved families and affected health care providers. Making this a care priority is complicated by a serious lack of data, as details of the last hours or weeks of a dying child or adolescent's life are largely unknown. The purpose of this paper is to identify key factors that affect the course of dying children and adolescents and that of their bereaved survivors, and to link those key factors to needed research that could produce clinically relevant findings to improve the care of these patients. Key factors described here include suffering (physical, psychological, and spiritual), communication, decision making, prognostic ambiguities, ability of the seriously ill child to give assent to research participation, and educational preparation of health care providers to give competent end-of-life care.

  8. Effects of natural factors on the spatial distribution of heavy metals in soils surrounding mining regions.

    PubMed

    Ding, Qian; Cheng, Gong; Wang, Yong; Zhuang, Dafang

    2017-02-01

    Various studies have shown that soils surrounding mining areas are seriously polluted with heavy metals. Determining the effects of natural factors on spatial distribution of heavy metals is important for determining the distribution characteristics of heavy metals in soils. In this study, an 8km buffer zone surrounding a typical non-ferrous metal mine in Suxian District of Hunan Province, China, was selected as the study area, and statistical, spatial autocorrelation and spatial interpolation analyses were used to obtain descriptive statistics and spatial autocorrelation characteristics of As, Pb, Cu, and Zn in soil. Additionally, the distributions of soil heavy metals under the influences of natural factors, including terrain (elevation and slope), wind direction and distance from a river, were determined. Layout of sampling sites, spatial changes of heavy metal contents at high elevations and concentration differences between upwind and downwind directions were then evaluated. The following results were obtained: (1) At low elevations, heavy metal concentrations decreased slightly, then increased considerably with increasing elevation. At high elevations, heavy metal concentrations first decreased, then increased, then decreased with increasing elevation. As the slope increased, heavy metal contents increased then decreased. (2) Heavy metal contents changed consistently in the upwind and downwind directions. Heavy metal contents were highest in 1km buffer zone and decreased with increasing distance from the mining area. The largest decrease in heavy metal concentrations was in 2km buffer zone. Perennial wind promotes the transport of heavy metals in downwind direction. (3) The spatial extent of the influence of the river on Pb, Zn and Cu in the soil was 800m. (4) The influence of the terrain on the heavy metal concentrations was greater than that of the wind. These results provide a scientific basis for preventing and mitigating heavy metal soil pollution in

  9. Genetic factors affecting dental caries risk.

    PubMed

    Opal, S; Garg, S; Jain, J; Walia, I

    2015-03-01

    This article reviews the literature on genetic aspects of dental caries and provides a framework for the rapidly changing disease model of caries. The scope is genetic aspects of various dental factors affecting dental caries. The PubMed database was searched for articles with keywords 'caries', 'genetics', 'taste', 'diet' and 'twins'. This was followed by extensive handsearching using reference lists from relevant articles. The post-genomic era will present many opportunities for improvement in oral health care but will also present a multitude of challenges. We can conclude from the literature that genes have a role to play in dental caries; however, both environmental and genetic factors have been implicated in the aetiology of caries. Additional studies will have to be conducted to replicate the findings in a different population. Identification of genetic risk factors will help screen and identify susceptible patients to better understand the contribution of genes in caries aetiopathogenesis. Information derived from these diverse studies will provide new tools to target individuals and/or populations for a more efficient and effective implementation of newer preventive measures and diagnostic and novel therapeutic approaches in the management of this disease. © 2015 Australian Dental Association.

  10. Factors affecting sustainability of rural water schemes in Swaziland

    NASA Astrophysics Data System (ADS)

    Peter, Graciana; Nkambule, Sizwe E.

    The Millennium Development Goal (MDG) target to reduce the proportion of people without sustainable access to safe drinking water by the year 2015 has been met as of 2010, but huge disparities exist. Some regions, particularly Sub-Saharan Africa are lagging behind it is also in this region where up to 30% of the rural schemes are not functional at any given time. There is need for more studies on factors affecting sustainability and necessary measures which when implemented will improve the sustainability of rural water schemes. The main objective of this study was to assess the main factors affecting the sustainability of rural water schemes in Swaziland using a Multi-Criteria Analysis Approach. The main factors considered were: financial, social, technical, environmental and institutional. The study was done in Lubombo region. Fifteen functional water schemes in 11 communities were studied. Data was collected using questionnaires, checklist and focused group discussion guide. A total of 174 heads of households were interviewed. Statistical Package for Social Sciences (SPSS) was used to analyse the data and to calculate sustainability scores for water schemes. SPSS was also used to classify sustainability scores according to sustainability categories: sustainable, partially sustainable and non-sustainable. The averages of the ratings for the different sub-factors studied and the results on the sustainability scores for the sustainable, partially sustainable and non-sustainable schemes were then computed and compared to establish the main factors influencing sustainability of the water schemes. The results indicated technical and social factors as most critical while financial and institutional, although important, played a lesser role. Factors which contributed to the sustainability of water schemes were: functionality; design flow; water fetching time; ability to meet additional demand; use by population; equity; participation in decision making on operation and

  11. Factors Affecting Online Groupwork Interest: A Multilevel Analysis

    ERIC Educational Resources Information Center

    Du, Jianxia; Xu, Jianzhong; Fan, Xitao

    2013-01-01

    The purpose of the present study is to examine the personal and contextual factors that may affect students' online groupwork interest. Using the data obtained from graduate students in an online course, both student- and group-level predictors for online groupwork interest were analyzed within the framework of hierarchical linear modeling…

  12. Factors Affecting the Technology Readiness of Health Professionals

    ERIC Educational Resources Information Center

    Myers, Stephanie E.

    2010-01-01

    Federal government policies are promoting diffusion of technologies into the healthcare system. If health professionals reject the new technologies planned for the healthcare system, it could result in costly failures, delays, and workforce problems. There is a lack of knowledge about factors that affect technology readiness (TR), defined as the…

  13. Factors affecting receipt of chemotherapy in women with breast cancer

    PubMed Central

    Morimoto, Libby; Coalson, Jenna; Mowat, Fionna; O’Malley, Cynthia

    2010-01-01

    Aims: To review literature describing factors associated with receipt of chemotherapy for breast cancer, to better understand what factors are most relevant to women’s health and whether health disparities are apparent, and to assess how these factors might affect observational studies and outcomes research. Patterns of care for metastatic breast cancer, for which no standard-of-care exists, were of particular interest. Methods: Relevant studies written in English, Italian, French, or Spanish, published in 2000 or later, were identified through MEDLINE and reviewed. Review articles and clinical trials were excluded; all observational studies and surveys were considered. Articles were reviewed for any discussion of patient characteristics, hospital/physician/insurance characteristics, psychosocial characteristics, and clinical characteristics affecting receipt of chemotherapy by breast cancer patients. Results: In general, factors associated with increased likelihood of receiving chemotherapy included younger age, being Caucasian, having good general health and few co-morbidities, having more severe clinical disease, having responded well to previous treatment, and having breast cancer that is estrogen- or progesterone-receptor-negative. Many of the clinical factors found to increase the likelihood of receiving chemotherapy were consistent with current oncology guidelines. Of the relevant 19 studies identified, only six (32%) reported data specific to metastatic cancer; most studies aggregated women with stage I–IV for purposes of analysis. Conclusion: Studies of patterns of care in breast cancer treatment can help identify challenges in health care provided to particular subgroups of women and can aid researchers in designing studies that account for such factors in clinical and outcomes research. Although scarce, studies evaluating only women with metastatic breast cancer indicate that factors affecting decisions related to receipt of chemotherapy are similar

  14. Battlefield Acquired Immunogenicity to Metals Affects Orthopaedic Implant Outcome

    DTIC Science & Technology

    2014-10-01

    consumer products: a role in allergic contact dermatitis ? Contact Dermatitis 1993;28:15-25. (13) Cramers M, Lucht U. Metal sensitivity in patients... dermatitis presumably due to metallic foreign bodies containing nickel or cobalt. Current Contact News 1977;19:285-95. (15) Benson MK, Goodwin PG...Sipilainen-Malm T, Estlander T, Zitting A, Jolanki R, Tarvainen K. Nickel release from metals, and a case of allergic contact dermatitis from

  15. Factors affecting the periapical healing process of endodontically treated teeth

    PubMed Central

    Holland, Roberto; Gomes, João Eduardo; Cintra, Luciano Tavares Angelo; Queiroz, Índia Olinta de Azevedo; Estrela, Carlos

    2017-01-01

    Abstract Tissue repair is an essential process that reestablishes tissue integrity and regular function. Nevertheless, different therapeutic factors and clinical conditions may interfere in this process of periapical healing. This review aims to discuss the important therapeutic factors associated with the clinical protocol used during root canal treatment and to highlight the systemic conditions associated with the periapical healing process of endodontically treated teeth. The antibacterial strategies indicated in the conventional treatment of an inflamed and infected pulp and the modulation of the host's immune response may assist in tissue repair, if wound healing has been hindered by infection. Systemic conditions, such as diabetes mellitus and hypertension, can also inhibit wound healing. The success of root canal treatment is affected by the correct choice of clinical protocol. These factors are dependent on the sanitization process (instrumentation, irrigant solution, irrigating strategies, and intracanal dressing), the apical limit of the root canal preparation and obturation, and the quality of the sealer. The challenges affecting the healing process of endodontically treated teeth include control of the inflammation of pulp or infectious processes and simultaneous neutralization of unpredictable provocations to the periapical tissue. Along with these factors, one must understand the local and general clinical conditions (systemic health of the patient) that affect the outcome of root canal treatment prediction. PMID:29069143

  16. Changes in metallothionein concentrations in response to variation in natural factors (salinity, sex, weight) and metal contamination in crabs from a metal-rich estuary.

    PubMed

    Legras; Mouneyrac; Amiard; Amiard-Triquet; Rainbow

    2000-04-05

    Intermoult male and female crabs Pachygrapsus marmoratus and Carcinus maenas were sampled from three sites between the mouth and 25 km upstream in the Gironde, the most Cd-contaminated estuary in France, in order to study the relative importance of natural factors (salinity, sex, weight) and accumulated metal concentrations on metallothionein (MT) concentrations. In the two species studied, higher metal, total protein and MT concentrations were observed in the hepatopancreas than in the gills. In P. marmoratus, MT concentrations were mainly related to changes in the natural factors even if MT and Zn concentrations were positively correlated in the hepatopancreas whereas in C. maenas, the main relationships were with accumulated metal levels. In the case of the natural factors, the most important ones were weight in gills of both crab species, and salinity changes in both hepatopancreas and gills of P. marmoratus. Cd and Cu concentrations in both organs of the two species were inversely related to salinity. The same observation was found for Zn concentrations in C. maenas but not in P. marmoratus. In the hepatopancreas of both species, the highest total protein concentrations were found in crabs from the site with the highest salinity, whereas there were no such differences in the gills. It seems that changes in MT concentrations are linked more to changes in general protein metabolism than to changes in metal accumulation. Thus it was important to examine the storage of metals in other tissue compartments, particularly the insoluble fraction which includes mineral granules which is known to also contribute to trace metal detoxification in invertebrates. In the gills of the crabs, Zn was present mainly in the insoluble fraction, whereas Cd was nearly equally distributed between soluble and insoluble fractions. In contrast, Cu in the gills and all three metals in the hepatopancreas of both species were mainly cytosolic, but this does not necessarily imply a

  17. Metal uptake of tomato and alfalfa plants as affected by water source, salinity, and Cd and Zn levels under greenhouse conditions.

    PubMed

    Gharaibeh, Mamoun A; Marschner, Bernd; Heinze, Stefanie

    2015-12-01

    Irrigation with wastewater is a promising option to improve crop yields and to reduce pressure on freshwater sources. However, heavy metal concentrations in wastewater may cause health concerns. A greenhouse pot experiment was conducted in order to determine cadmium (Cd) and zinc (Zn) concentrations in sandy soil and plant tissues of tomato (Lycopersicon esculentum L.) and alfalfa (Medicago sativa L.). A 2 × 2 × 4 × 2 factorial treatment arrangement was utilized. Two water sources, fresh (FW) or treated wastewater (TWW), at two salinity levels (1 and 3 dS m(-1)) containing different levels of Cd and Zn were used. Samples were collected after a 90-day growth period. It was observed that the growth of both plants was depressed at the highest metal level (L3). Metal accumulation in plant parts increased with the increase of metal concentration and salinity in irrigation water. At low salinity, water source was the main factor which controlled metal accumulation, whereas, at high salinity, chloride appeared to be the principal factor controlling metal uptake regardless of water source. Metal translocation from roots to shoots increased in TWW-irrigated plants, even in the controls. Tomatoes accumulated Cd up to and above critical levels safe for human consumption, even though Cd concentration in irrigation water did not exceed the current recommended values. Therefore, food production in sandy soils may well pose a health hazard when irrigated with TWW containing heavy metals. Complexation with dissolved organic compounds (DOC) in TWW may be to be the principal factor responsible for increased metal uptake and transfer at low salinity, thereby increasing the risk of heavy metal contamination of food and forage crops.

  18. Factors affecting outcome in ocular myasthenia gravis.

    PubMed

    Mazzoli, Marco; Ariatti, Alessandra; Valzania, Franco; Kaleci, Shaniko; Tondelli, Manuela; Nichelli, Paolo F; Galassi, Giuliana

    2018-01-01

    50%-60% of patients with ocular myasthenia gravis (OMG) progress to generalized myasthenia gravis (GMG) within two years. The aim of our study was to explore factors affecting prognosis of OMG and to test the predictive role of several independent clinical variables. We reviewed a cohort of 168 Caucasian patients followed from September 2000 to January 2016. Several independent variables were considered as prognostic factors: gender, age of onset, results on electrophysiological tests, presence and level of antibodies against acetylcholine receptors (AChR Abs), treatments, thymic abnormalities. The primary outcome was the progression to GMG and/or the presence of bulbar symptoms. Secondary outcomes were either achievement of sustained minimal manifestation status or worsening in ocular quantitative MG subscore (O-QMGS) or worsening in total QMG score (T-QMGS), assessed by Myasthenia Gravis Foundation of America (MGFA) quantitative scores. Changes in mental and physical subscores of health-related quality of life (HRQoL) were assessed with SF-36 questionnaire. Variance analysis was used to interpret the differences between AChR Ab titers at different times of follow up among the generalized and non-generalized patients. Conversion to GMG occurred in 18.4% of patients; it was significantly associated with sex, later onset of disease and anti-AChR Ab positivity. Antibody titer above the mean value of 25.8 pmol/mL showed no significant effect on generalization. Sex and late onset of disease significantly affected T-QMGS worsening. None of the other independent variables significantly affected O-QMGS and HRQoL. Sex, later onset and anti-AChR Ab positivity were significantly associated with clinical worsening.

  19. Factors affecting sexual function in menopause: A review article.

    PubMed

    Nazarpour, Soheila; Simbar, Masoumeh; Tehrani, Fahimeh Ramezani

    2016-08-01

    This study aimed to systematically review the articles on factors affecting sexual function during menopause. Searching articles indexed in Pubmed, Science Direct, Iranmedex, EMBASE, Scopus, and Scientific Information Database databases, a total number of 42 studies published between 2003 and 2013 were selected. Age, estrogen deficiency, type of menopause, chronic medical problems, partner's sex problems, severity of menopause symptoms, dystocia history, and health status were the physical factors influencing sexual function of menopausal women. There were conflicting results regarding the amount of androgens, hormonal therapy, exercise/physical activity, and obstetric history. In the mental-emotional area, all studies confirmed the impact of depression and anxiety. Social factors, including smoking, alcohol consumption, the quality of relationship with husband, partner's loyalty, sexual knowledge, access to health care, a history of divorce or the death of a husband, living apart from a spouse, and a negative understanding of women's health were found to affect sexual function; however, there were conflicting results regarding the effects of education, occupation, socioeconomic status, marital duration, and frequency of sexual intercourse. Copyright © 2016. Published by Elsevier B.V.

  20. From the Soil to the Seed. Metal Transport in Arabidopsis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guerinot, Mary Lou

    2015-02-27

    Deficiencies of micronutrients such as Fe, Mn, and Zn commonly limit plant growth and crop yields. The long-term goals of our program are to understand how plants acquire metal micronutrients from the soil and distribute them while protecting themselves from the potential redox damage metals can cause to living tissues. Metals serve as important co-factors for photosynthesis and respiration, yet we still know very little about metal transport. Our approach combines experimental and computational tools from the physical sciences with biochemistry and molecular biology. Specifically, we combine mutant analysis with synchrotron X-ray fluorescence (SXRF) spectroscopy, a technique that allows usmore » to image the elemental composition of living plant material in 3-D. By analyzing the phenotypes of lines carrying mutations in various metal transporters, we have identified the genes responsible for uptake of zinc from the soil as well as genes involved in loading the seeds with metal micronutrients. Several of these transporters affect the localization of metals in the seed without affecting the overall metal content. Understanding how seeds obtain and store nutrients is key to developing crops with higher agronomic and nutritional value.« less

  1. Assessments of chromium (and other metals) in vegetables and potential bio-accumulations in humans living in areas affected by tannery wastes.

    PubMed

    Chen, Hualin; Arocena, Joselito M; Li, Jianbing; Thring, Ronald W; Zhou, Jiangmin

    2014-10-01

    Chromium (Cr) commonly enters the food chain through uptake by vegetables. However, accurate prediction of plant uptake of Cr (and other metals) still remains a challenge. In this study, we evaluated 5 indices of availability for Cr (and other metals) to identify reliable predictors of metal transfer from soils to garlic, onion, bokchoy, radish and celery grown in soils impacted by tannery wastes. The potential bio-accumulation of Cr in humans was calculated from the Cr content of vegetable predicted by the best bio-availability index, amounts of vegetable consumed and recommended daily doses for Cr. Our results show that soil total Cr is the best predictor of Cr transfer from soils to onion (Cr in onion=8.51+0.005 Total Cr) while Cr extractable by Synthetic Precipitation Leaching Procedure at pH 5 correlates very well with Cr uptake by bokchoy (Cr bokchoy=5.86+7.32 SPLP-5 Cr) and garlic (Cr garlic=7.63+2.36 SPLP-5 Cr). The uptake of Cr by radish and celery could not be reliably estimated by any of the 5 indices of availability tested in this study. Potential bio-accumulation of Cr in humans (BA-Cr) increases from soils with low Cr (BA-Cr=11.5) to soil with high total Cr (BA-Cr=31.3). Due to numerous soil factors affecting the behavior of Cr in soils and the physiological differences among vegetables, we suggest that the prediction of the transfer of Cr (and other metals) from soils to plants should be specific to site, metal and vegetable. Potential bio-accumulation of Cr in humans can be derived from a transfer function of Cr from soils to plants and the human consumption of vegetables. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Analysis on factors affecting consumers decision on purchasing simple-type houses

    NASA Astrophysics Data System (ADS)

    Rumintang, A.; Sholichin, I.

    2018-01-01

    In line with the increase of the population and the need of comfortable houses, as affected by modernization era, the house demand is getting higher. Hence, conducting a research on consumers need and want in buying a house should be seriously attempted to succeed marketing activity. Using an analysis consumers’ behavior, the researcher will know few affecting factors related to consumers’ satisfaction in buying a house. Among other, the factors in question include: house price, house condition, facilities, location and accessability. The sample of this research was drawn from the residents of Graha Asri Housing, Taman Bulang Permai, and Sukodono Permai. Based on the analysis and discussion, some conclusions are made as follow: the factors and variables affecting the consumers’ decision on each choice of house is different and also the same variables on three sources of data include housing atmosphere, cleaning service, ease of access to shopping center, health clinics or hospitals, tourism spot, schools, and the bus station.

  3. Understanding the factors influencing the removal of heavy metals in urban stormwater runoff.

    PubMed

    Maniquiz-Redillas, Marla C; Kim, Lee-Hyung

    2016-01-01

    In this research, an infiltration trench equipped with an extensive pretreatment and filter bed consisting of woodchip, sand and gravel was utilized as a low impact development technique to manage stormwater runoff from a highly impervious road with particular emphasis on heavy metal removal. Findings revealed that the major factors influencing the removal of heavy metals were the concentration of the particulate matters and heavy metals in runoff, runoff volume and flow rates. The reduction of heavy metals was enhanced by sedimentation of particulates through pretreatment. Fine particles (<2 mm) had the most significant amount of heavy metals, thus, enhanced adsorption and filtration using various filter media were important design considerations. Sediment was most highly attached on the surface area of woodchip than to other filter media like sand, gravel and geotextile. It is suggested that maintenance must be performed after the end of the winter season wherein high sediment rate was observed to maintain the efficiency of the treatment system.

  4. 14 CFR Appendix B to Part 1215 - Factors Affecting Standard Charges

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... DATA RELAY SATELLITE SYSTEM (TDRSS) Pt. 1215, App. B Appendix B to Part 1215—Factors Affecting Standard Charges Charges for services shall be determined by multiplying the factors below by the base rates for...

  5. Other Factors That Affect Heart Disease: Birth Control Pills

    MedlinePlus

    ... Heart Handbook for Women Other Factors That Affect Heart Disease Birth Control Pills Studies show that women who ... t had any more complications because of my heart disease." — Diane Pay attention to diabetes. Levels of glucose, ...

  6. Reappraising factors affecting mourning dove perch coos

    USGS Publications Warehouse

    Sayre, M.W.; Atkinson, R.D.; Baskett, T.S.; Haas, G.H.

    1978-01-01

    Results confirmed pairing as the primary factor influencing perch-cooing rates of wild mourning doves (Zenaida macroura). Marked unmated males cooed at substantially higher rates (6.2x) than mated males, had greater probability of cooing (2.3x) during 3-minute periods, and continued cooing longer each morning than mated males. Population density was not a major factor affecting cooing. Unmated males cooed more frequently in the presence of other cooing doves (P < 0.05) than when alone, but the number of additional doves above 1 was unimportant. Cooing rates of both mated and unmated males on areas with dissimilar dove densities were not significantly different. Within limits of standard call-count procedure, weather exerted no detectable influence on cooing.

  7. A Study on Factors Affecting the Degradation of Magnesium and a Magnesium-Yttrium Alloy for Biomedical Applications

    PubMed Central

    Johnson, Ian; Liu, Huinan

    2013-01-01

    Controlling degradation of magnesium or its alloys in physiological saline solutions is essential for their potential applications in clinically viable implants. Rapid degradation of magnesium-based materials reduces the mechanical properties of implants prematurely and severely increases alkalinity of the local environment. Therefore, the objective of this study is to investigate the effects of three interactive factors on magnesium degradation, specifically, the addition of yttrium to form a magnesium-yttrium alloy versus pure magnesium, the metallic versus oxide surfaces, and the presence versus absence of physiological salt ions in the immersion solution. In the immersion solution of phosphate buffered saline (PBS), the magnesium-yttrium alloy with metallic surface degraded the slowest, followed by pure magnesium with metallic or oxide surfaces, and the magnesium-yttrium alloy with oxide surface degraded the fastest. However, in deionized (DI) water, the degradation rate showed a different trend. Specifically, pure magnesium with metallic or oxide surfaces degraded the slowest, followed by the magnesium-yttrium alloy with oxide surface, and the magnesium-yttrium alloy with metallic surface degraded the fastest. Interestingly, only magnesium-yttrium alloy with metallic surface degraded slower in PBS than in DI water, while all the other samples degraded faster in PBS than in DI water. Clearly, the results showed that the alloy composition, presence or absence of surface oxide layer, and presence or absence of physiological salt ions in the immersion solution all influenced the degradation rate and mode. Moreover, these three factors showed statistically significant interactions. This study revealed the complex interrelationships among these factors and their respective contributions to degradation for the first time. The results of this study not only improved our understanding of magnesium degradation in physiological environment, but also presented the key

  8. Organisational Factors Affecting Policy and Programme Decision Making in a Public Health Policy Environment

    ERIC Educational Resources Information Center

    Zardo, Pauline; Collie, Alex; Livingstone, Charles

    2015-01-01

    Organisational factors can affect the success of interventions aimed at increasing research use. Research is needed to identify organisational factors affecting research use in specific public health policy contexts. Qualitative interviews with decision makers from a specific public health context identified a range of organisational factors that…

  9. Factors affecting dental service quality.

    PubMed

    Bahadori, Mohammadkarim; Raadabadi, Mehdi; Ravangard, Ramin; Baldacchino, Donia

    2015-01-01

    Measuring dental clinic service quality is the first and most important factor in improving care. The quality provided plays an important role in patient satisfaction. The purpose of this paper is to identify factors affecting dental service quality from the patients' viewpoint. This cross-sectional, descriptive-analytical study was conducted in a dental clinic in Tehran between January and June 2014. A sample of 385 patients was selected from two work shifts using stratified sampling proportional to size and simple random sampling methods. The data were collected, a self-administered questionnaire designed for the purpose of the study, based on the Parasuraman and Zeithaml's model of service quality which consisted of two parts: the patients' demographic characteristics and a 30-item questionnaire to measure the five dimensions of the service quality. The collected data were analysed using SPSS 21.0 and Amos 18.0 through some descriptive statistics such as mean, standard deviation, as well as analytical methods, including confirmatory factor. Results showed that the correlation coefficients for all dimensions were higher than 0.5. In this model, assurance (regression weight=0.99) and tangibility (regression weight=0.86) had, respectively, the highest and lowest effects on dental service quality. The Parasuraman and Zeithaml's model is suitable to measure quality in dental services. The variables related to dental services quality have been made according to the model. This is a pioneering study that uses Parasuraman and Zeithaml's model and CFA in a dental setting. This study provides useful insights and guidance for dental service quality assurance.

  10. Exploring Factors that Affect Purchase Intention of Athletic Team Merchandise

    ERIC Educational Resources Information Center

    Lee, Donghun; Trail, Galen T.; Lee, Cindy; Schoenstedt, Linda J.

    2013-01-01

    The purpose of this study was to test a structural model to determine which psychosocial constructs affected the purchase intention of athletic team merchandise (ATM). Results from the analyses indicated that the twelve-factor ATM model fit the data from collegiate athletic events well, explaining the various impact factors that lead to purchase…

  11. The remediation of heavy metals contaminated sediment.

    PubMed

    Peng, Jian-Feng; Song, Yong-Hui; Yuan, Peng; Cui, Xiao-Yu; Qiu, Guang-Lei

    2009-01-30

    Heavy metal contamination has become a worldwide problem through disturbing the normal functions of rivers and lakes. Sediment, as the largest storage and resources of heavy metal, plays a rather important role in metal transformations. This paper provides a review on the geochemical forms, affecting factors and remediation technologies of heavy metal in sediment. The in situ remediation of sediment aims at increasing the stabilization of some metals such as the mobile and the exchangeable fractions; whereas, the ex situ remediation mainly aims at removing those potentially mobile metals, such as the Mn-oxides and the organic matter (OM) fraction. The pH and OM can directly change metals distribution in sediment; however oxidation-reduction potential (ORP), mainly through changing the pH values, indirectly alters metals distribution. Mainly ascribed to their simple operation mode, low costs and fast remediation effects, in situ remediation technologies, especially being fit for slight pollution sediment, are applied widely. However, for avoiding metal secondary pollution from sediment release, ex situ remediation should be the hot point in future research.

  12. 29 CFR 784.118 - The exemption is intended for work affected by natural factors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false The exemption is intended for work affected by natural...(a)(5) Exemption § 784.118 The exemption is intended for work affected by natural factors. As... that are controlled or materially affected by natural factors or elements, such as the vicissitudes of...

  13. 29 CFR 784.118 - The exemption is intended for work affected by natural factors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false The exemption is intended for work affected by natural...(a)(5) Exemption § 784.118 The exemption is intended for work affected by natural factors. As... that are controlled or materially affected by natural factors or elements, such as the vicissitudes of...

  14. Formal Classroom Observations: Factors That Affect Their Success

    ERIC Educational Resources Information Center

    Zaidi, Zeba

    2017-01-01

    Formal class room observation is a very delicate topic in any educational institution. It involves a series of emotions and sentiments that come with the package. In this paper, the researcher will attempt to analyze the factors that affect the process in a relatively significant manner and thereby contribute greatly to the success or failure of…

  15. Factors affecting patient compliance with compressive brace therapy for pectus carinatum.

    PubMed

    Kang, Du-Young; Jung, Junho; Chung, Sangho; Cho, Jinkyung; Lee, Sungsoo

    2014-12-01

    The aim of this study was to identify factors affecting patient compliance with brace therapy for pectus carinatum. Eighty-six pectus carinatum patients who started brace therapy from August 2008 to November 2011 were included in this study. Patients were divided into two groups: patients who wore the brace for ≥6 months (compliance group) or patients who wore the brace for <6 months (non-compliance group). Factors affecting patient compliance were assessed at the last day of follow-up with a multiple-choice questionnaire. The questionnaire comprised seven items: pain at compression site, skin problems on compression area, confidence in brace treatment, shame, discomfort, initial result of bracing treatment and total number of factors affecting patient compliance. Eighty-six patients completed the survey, including seven (8.1%) female patients and 79 (91.9%) male patients, with a mean age of 12.0 years at the time of treatment (range, 3-20 years). The initial result of the compression period (P <0.001) and total number of factors affecting patient compliance (P <0.05) were significant predictors of patient compliance. An initial successful result of the compression period may increase patient compliance during treatment for pectus carinatum. Additional efforts to decrease pain, skin problems, shame and discomfort, and to give confidence may be beneficial in increasing compliance with bracing treatment. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  16. Factors affecting scholastic performances of adolescents.

    PubMed

    Shashidhar, Saraswati; Rao, Chandrika; Hegde, Radhakrishna

    2009-05-01

    The present study aims at recognizing the social influence, study habits and health factors affecting scholastic performances of adolescents and to compare these factors among the adolescents between two categories of school. A total of 1230 adolescents (13-18 yrs) were screened. Data was collected by personal interview, using the teenage screening questionnaire, Trivandrum, between May 2004 and November 2005. A total 615 students from corporation and private schools were studied. 39.76% (489) were high achievers, 13.5% (166) were low achievers with p < 0.001. In the low achievers, 12.03% were from the corporation schools and 1.46% from private schools. The incidence of poor study habits and social factors were increased in low achievers of corporation schools. On multivariate analysis, the predictor variables for poor scholastic performance were adolescent having refractory error, not having help for study at home, not doing home work regularly, not solving question bank papers and reading only before examinations. It is feasible and worthwhile to identify the determinants of scholastic performance and plan intervention strategies at each school. The results of this study highlight the importance of implementing newer strategies, focusing on strict study patterns and creating the conducive school and home environment for study, so as to achieve better scholastic performances.

  17. Factors affecting maintenance overlay ride quality : 1996 rideability status.

    DOT National Transportation Integrated Search

    1997-01-01

    In early 1996, the Virginia Transportation Research Council initiated a formal analysis of the factors affecting overlay ride quality. As part of that effort, a statewide, multi-year survey of the ride quality for both new overlays and pavement await...

  18. Temperature and metal exposure affect membrane fatty acid composition and transcription of desaturases and elongases in fathead minnow muscle and brain.

    PubMed

    Fadhlaoui, Mariem; Pierron, Fabien; Couture, Patrice

    2018-02-01

    In this study, we tested the hypothesis that metal exposure affected the normal thermal response of cell membrane FA composition and of elongase and desaturase gene transcription levels. To this end, muscle and brain membrane FA composition and FA desaturase (fads2, degs2 and scd2) and elongase (elovl2, elovl5 and elovl6) gene transcription levels were analyzed in fathead minnows (Pimephales promelas) acclimated for eight weeks to 15, 25 or 30°C exposed or not to cadmium (Cd, 6μg/l) or nickel (Ni, 450 6μg/l). The response of membrane FA composition to temperature variations or metal exposure differed between muscle and brain. In muscle, an increase of temperature induced a decrease of polyunsaturated FA (PUFA) and an increase of saturated FA (SFA) in agreement with the current paradigm. Although a similar response was observed in brain between 15 and 25°C, at 30°C, brain membrane unsaturation was higher than predicted. In both tissues, metal exposure affected the normal thermal response of membrane FA composition. The transcription of desaturases and elongases was higher in the brain and varied with acclimation temperature and metal exposure but these variations did not generally reflect changes in membrane FA composition. The mismatch between gene transcription and membrane composition highlights that several levels of control other than gene transcription are involved in adjusting membrane FA composition, including post-transcriptional regulation of elongases and desaturases and de novo phospholipid biosynthesis. Our study also reveals that metal exposure affects the mechanisms involved in adjusting cell membrane FA composition in ectotherms. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. External factors affecting data acquisition during corneal topography examination.

    PubMed

    González-Méijome, José Manuel; Queirós, Antonio; Jorge, Jorge; Fernandes, Paulo; Cerviño, Alejandro; de Almeida, José Borges

    2007-03-01

    To analyze the factors affecting data acquisition during corneal topography examination with the Medmont E-300 videokeratoscope and to provide strategies to minimize their effects. Sixty eyes from thirty young adults were examined. A second observer registered incidences with the potential to affect data acquisition. Those factors were correlated with the difficulty of measurements as judged subjectively by the practitioner who performed the examination. Measurements of axial curvature were analyzed to evaluate the variability expressed as intrasession and intersession coefficient of variation and the standard error of the mean (SEM). The level of difficulty rated by the practitioner was in general low, with 70% of the eyes being easy or very easy to measure. For the remaining 30% of the eyes, corneal topography measurements were considered to be difficult (27%) or very difficult (3%). Of the external parameters investigated, only fixation instability (P<0.001, chi2) and the need for head repositioning (P=0.024, chi2) were associated significantly with a higher level of difficulty, as rated subjectively by the practitioner. Further analysis showed that some external factors, including those previously mentioned and others related to tear instability, affect the variability of measurements at certain corneal locations, particularly in the vertical meridian when related to tear instability and in the horizontal meridian when related to the need for head repositioning on the chin rest owing to physiognomy interferences with the keratoscope cone. Intersession SEM improved when three readings from each session were considered. The level of subjective difficulty found during videokeratoscopy examination is correlated strongly with fixation instability and the need for head reorientation in the chin rest, whereas tear-related events seem to be less relevant in the practitioner perception of test ease or difficulty. Those factors have relevance in measurement variability.

  20. Factors affecting 30-month survival in lung cancer patients.

    PubMed

    Mahesh, P A; Archana, S; Jayaraj, B S; Patil, Shekar; Chaya, S K; Shashidhar, H P; Sunitha, B S; Prabhakar, A K

    2012-10-01

    Age adjusted incidence rate of lung cancer in India ranges from 7.4 to 13.1 per 100,000 among males and 3.9 to 5.8 per 100,000 among females. The factors affecting survival in lung cancer patients in India are not fully understood. The current study was undertaken to evaluate the factors affecting survival in patients diagnosed with lung cancer attending a tertiary care cancer institute in Bangalore, Karnataka, India. Consecutive patients with primary lung cancer attending Bangalore Institute of Oncology, a tertiary care centre at Bangalore, between 2006 and 2009 were included. Demographic, clinical, radiological data were collected retrospectively from the medical records. A total of 170 consecutive subjects (128 males, 42 females) diagnosed to have lung cancer; 151 non-small cell lung cancer (NSCLC) and 19 small cell lung cancer (SCLC) were included. A higher proportion of never-smokers (54.1%) were observed, mostly presenting below the age of 60 yr. Most subjects were in stage IV and III at the time of diagnosis. More than 50 per cent of patients presented with late stage lung cancer even though the duration of symptoms is less than 2 months. The 30-month overall survival rates for smokers and never-smokers were 32 and 49 per cent, respectively. No significant differences were observed in 30 month survival based on age at presentation, gender and type of lung cancer. Cox proportional hazards model identified never-smokers and duration of symptoms less than 1 month as factors adversely affecting survival. Our results showed that lung cancer in Indians involved younger subjects and associated with poorer survival as compared to other ethnic population. Studies on large sample need to be done to evaluate risk factors in lung cancer patients.

  1. Factors affecting 30-month survival in lung cancer patients

    PubMed Central

    Mahesh, P.A.; Archana, S.; Jayaraj, B.S.; Patil, Shekar; Chaya, S.K.; Shashidhar, H.P.; Sunitha, B.S.; Prabhakar, A.K.

    2012-01-01

    Background & objectives: Age adjusted incidence rate of lung cancer in India ranges from 7.4 to 13.1 per 100,000 among males and 3.9 to 5.8 per 100,000 among females. The factors affecting survival in lung cancer patients in India are not fully understood. The current study was undertaken to evaluate the factors affecting survival in patients diagnosed with lung cancer attending a tertiary care cancer institute in Bangalore, Karnataka, India. Methods: Consecutive patients with primary lung cancer attending Bangalore Institute of Oncology, a tertiary care centre at Bangalore, between 2006 and 2009 were included. Demographic, clinical, radiological data were collected retrospectively from the medical records. Results: A total of 170 consecutive subjects (128 males, 42 females) diagnosed to have lung cancer; 151 non-small cell lung cancer (NSCLC) and 19 small cell lung cancer (SCLC) were included. A higher proportion of never-smokers (54.1%) were observed, mostly presenting below the age of 60 yr. Most subjects were in stage IV and III at the time of diagnosis. More than 50 per cent of patients presented with late stage lung cancer even though the duration of symptoms is less than 2 months. The 30-month overall survival rates for smokers and never-smokers were 32 and 49 per cent, respectively. No significant differences were observed in 30 month survival based on age at presentation, gender and type of lung cancer. Cox proportional hazards model identified never-smokers and duration of symptoms less than 1 month as factors adversely affecting survival. Interpretation & conclusions: Our results showed that lung cancer in Indians involved younger subjects and associated with poorer survival as compared to other ethnic population. Studies on large sample need to be done to evaluate risk factors in lung cancer patients. PMID:23168702

  2. Factors affecting medication-order processing time.

    PubMed

    Beaman, M A; Kotzan, J A

    1982-11-01

    The factors affecting medication-order processing time at one hospital were studied. The order processing time was determined by directly observing the time to process randomly selected new drug orders on all three work shifts during two one-week periods. An order could list more than one drug for an individual patient. The observer recorded the nature, location, and cost of the drugs ordered, as well as the time to process the order. The time and type of interruptions also were noted. The time to process a drug order was classified as six dependent variables: (1) total time, (2) work time, (3) check time, (4) waiting time I--time from arrival on the dumbwaiter until work was initiated, (5) waiting time II--time between completion of the work and initiation of checking, and (6) waiting time III--time after the check was completed until the order left on the dumbwaiter. The significant predictors of each of the six dependent variables were determined using stepwise multiple regression. The total time to process a prescription order was 58.33 +/- 48.72 minutes; the urgency status of the order was the only significant determinant of total time. Urgency status also significantly predicted the three waiting-time variables. Interruptions and the number of drugs on the order were significant determinants of work time and check time. Each telephone interruption increased the work time by 1.72 minutes. While the results of this study cannot be generalized to other institutions, pharmacy managers can use the method of determining factors that affect medication-order processing time to identify problem areas in their institutions.

  3. Heavy metal phytoextraction by Sedum alfredii is affected by continual clipping and phosphorus fertilization amendment.

    PubMed

    Huang, Huagang; Li, Tingqiang; Gupta, D K; He, Zhenli; Yang, Xiao-E; Ni, Bingnan; Li, Mao

    2012-01-01

    Improving the efficacy of phytoextraction is critical for its successful application in metal contaminated soils. Mineral nutrition affects plant growth and metal absorption and subsequently the accumulation of heavy metal through hyper-accumulator plants. This study assessed the effects of di-hydrogen phosphates (KH2PO4, Ca(H2PO4)2, NaH2PO4 and NH4H2PO4) application at three levels (22, 88 and 352 mg P/kg soil) on Sedum alfredii growth and metal uptake by three consecutive harvests on aged and Zn/Cd combined contaminated paddy soil. The addition of phosphates (P) significantly increased the amount of Zn taken up by S. alfredii due to increased shoot Zn concentration and dry matter yield (DMY) (P < 0.05). The highest phytoextraction of Zn and Cd was observed in KH2PO4 and NH4H2PO4 treatment at 352 mg P/kg soil. The amount of Zn removed by phytoextraction increased in the order of 1st clipping < 2nd clipping < 3rd clipping, and for Cd extraction the order was 2nd clipping < 1st clipping < 3rd clipping. These results indicate that the application of P fertilizers coupled with multiple cuttings can enhance the removal of Zn and Cd from contaminated soils by S. alfredii, thus shortening the time needed for accomplishing remediation goals.

  4. The parkin Mutant Phenotype in the Fly Is Largely Rescued by Metal-Responsive Transcription Factor (MTF-1) ▿ †

    PubMed Central

    Saini, Nidhi; Georgiev, Oleg; Schaffner, Walter

    2011-01-01

    The gene for Parkin, an E3 ubiquitin ligase, is mutated in some familial forms of Parkinson's disease, a severe neurodegenerative disorder. A homozygous mutant of the Drosophila ortholog of human parkin is viable but results in severe motoric impairment including an inability to fly, female and male sterility, and a decreased life span. We show here that a double mutant of the genes for Parkin and the metal-responsive transcription factor 1 (MTF-1) is not viable. MTF-1, which is conserved from insects to mammals, is a key regulator of heavy metal homeostasis and detoxification and plays additional roles in other stress conditions, notably oxidative stress. In contrast to the synthetic lethality of the double mutant, elevated expression of MTF-1 dramatically ameliorates the parkin mutant phenotype, as evidenced by a prolonged life span, motoric improvement including short flight episodes, and female fertility. At the cellular level, muscle and mitochondrial structures are substantially improved. A beneficial effect is also seen with a transgene encoding human MTF-1. We propose that Parkin and MTF-1 provide complementary functions in metal homeostasis, oxidative stress and other cellular stress responses. Our findings also raise the possibility that MTF-1 gene polymorphisms in humans could affect the severity of Parkinson's disease. PMID:21383066

  5. Merging black hole binaries: the effects of progenitor's metallicity, mass-loss rate and Eddington factor

    NASA Astrophysics Data System (ADS)

    Giacobbo, Nicola; Mapelli, Michela; Spera, Mario

    2018-03-01

    The first four gravitational wave events detected by LIGO were all interpreted as merging black hole binaries (BHBs), opening a new perspective on the study of such systems. Here we use our new population-synthesis code MOBSE, an upgraded version of BSE, to investigate the demography of merging BHBs. MOBSE includes metallicity-dependent prescriptions for mass-loss of massive hot stars. It also accounts for the impact of the electron-scattering Eddington factor on mass-loss. We perform >108 simulations of isolated massive binaries, with 12 different metallicities, to study the impact of mass-loss, core-collapse supernovae and common envelope on merging BHBs. Accounting for the dependence of stellar winds on the Eddington factor leads to the formation of black holes (BHs) with mass up to 65 M⊙ at metallicity Z ˜ 0.0002. However, most BHs in merging BHBs have masses ≲ 40 M⊙. We find merging BHBs with mass ratios in the 0.1-1.0 range, even if mass ratios >0.6 are more likely. We predict that systems like GW150914, GW170814 and GW170104 can form only from progenitors with metallicity Z ≤ 0.006, Z ≤ 0.008 and Z ≤ 0.012, respectively. Most merging BHBs have gone through a common envelope phase, but up to ˜17 per cent merging BHBs at low metallicity did not undergo any common envelope phase. We find a much higher number of mergers from metal-poor progenitors than from metal-rich ones: the number of BHB mergers per unit mass is ˜10-4 M_{⊙}^{-1} at low metallicity (Z = 0.0002-0.002) and drops to ˜10-7 M_{⊙}^{-1} at high metallicity (Z ˜ 0.02).

  6. Critical review of heavy metal pollution of traffic area runoff: Occurrence, influencing factors, and partitioning.

    PubMed

    Huber, Maximilian; Welker, Antje; Helmreich, Brigitte

    2016-01-15

    A dataset of 294 monitored sites from six continents (Africa, Asia, Australia, Europe, North and South America) was compiled and evaluated to characterize the occurrence and fate of heavy metals in eight traffic area categories (parking lots, bridges, and three types each of both roads and highways). In addition, site-specific (fixed and climatic) and method-specific (related to sample collection, preparation, and analysis) factors that influence the results of the studies are summarized. These factors should be considered in site descriptions, conducting monitoring programs, and implementing a database for further research. Historical trends for Pb show a sharp decrease during recent decades, and the median total Pb concentrations of the 21st century for North America and Europe are approximately 15 μg/L. No historical trend is detected for Zn. Zn concentrations are very variable in traffic area runoff compared with other heavy metals because of its presence in galvanized structures and crumbs of car tire rubber. Heavy metal runoff concentrations of parking lots differ widely according to their use (e.g., employee, supermarket, rest areas for trucks). Bridge deck runoff can contain high Zn concentrations from safety fences and galvanizing elements. Roads with more than 5000 vehicles per day are often more polluted than highways because of other site-specific factors such as traffic signals. Four relevant heavy metals (Zn, Cu, Ni, and Cd) can occur in the dissolved phase. Knowledge of metal partitioning is important to optimize stormwater treatment strategies and prevent toxic effects to organisms in receiving waters. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Teaching the Factors Affecting Resistance Using Pencil Leads

    ERIC Educational Resources Information Center

    Küçüközer, Asuman

    2015-01-01

    The aim of this paper is to provide a way of teaching the factors that affect resistance using mechanical pencil leads and the brightness of the light given out by a light bulb connected to an electrical circuit. The resistance of a conductor is directly proportional to its length (L) and inversely proportional to its cross-sectional area (A).…

  8. Elucidation of Proton-Assisted Fluxionality in Transition-Metal Oxide Clusters

    NASA Astrophysics Data System (ADS)

    Ramabhadran, Raghunath O.; Mayhall, Nicholas J.; Becher, Edwin L. Becher, Iii; Chowdhury, Arefin; Raghavachari, Krishnan

    2012-06-01

    The phenomenon of fluxionality in the reactions of transition-metal oxide clusters provides many opportunities in various industrial and catalytic processes. We present an electronic structure investigation of the fluxionality pathways when anionic W3O6- and Mo3O6- clusters react with three small molecules - water, ammonia and hydrogen sulfide. The presentation features a detailed understanding of (a) how the fluxionality pathway occurs and (b) the various factors that affect the fluxionality pathway - such as the metal, different spin-states and the nature of the non-metal in the reacting small molecule.

  9. Culture and affect: the factor structure of the affective style questionnaire and its relation with depression and anxiety among Japanese.

    PubMed

    Ito, Masaya; Hofmann, Stefan G

    2014-09-02

    Affective styles are assumed to be one of the underlying processes of depression and anxiety maintenance. However, little is known about the effect of depression and anxiety and the cultural influence of the factor structure. Here, we examined the cross-cultural validity of the Affective Style Questionnaire and its incremental validity for the influence on depression and anxiety. Affective Style Questionnaire was translated into Japanese using standard back-translation procedure. Japanese university students (N = 1,041) served as participants. Emotion Regulation Questionnaire, Acceptance and Action Questionnaire-II, Toronto Alexithymia Scale, Rumination and Reflection Questionnaire, Brief COPE, Self-Construal Scale, and Hospital Anxiety and Depression Scale were administered. Exploratory and confirmatory factor analyses showed that the Affective Style Questionnaire comprised four factors: Concealing, Adjusting, Holding and Tolerating (CFI = .92, TLI = .90, RMSEA = .07). The measure's convergent and discriminant validity was substantiated by its association with various emotion regulation measures. Regression analyses showed that negative influence of Adjusting, Holding, Reappraisal (β = -.17, -.19, -.30) and positive influence of Suppression (β = .23) were observed on depression. For anxiety, Adjusting and Reappraisal was negatively influenced (β = -.29, and -.18). Reliability and validity of the Affective Style Questionnaire was partly confirmed. Further study is needed to clarify the culturally dependent aspects of affective styles.

  10. Factors That Affect the Academic Success of Foreign Students at Cardinal Stritch University

    ERIC Educational Resources Information Center

    Annor, Peter

    2010-01-01

    There are limited studies in the literature on the factors that affect the academic success of foreign students in the United States. This ex post facto mixed method study investigated the factors that affect the academic success of foreign students at Cardinal Stitch University (CSU), a medium size, private university located in the Midwestern…

  11. Looking under the Bonnet: Factors Affecting Student Adoption of E-Learning Systems in Jordan

    ERIC Educational Resources Information Center

    Abbad, Muneer Mahmood; Morris, David; de Nahlik, Carmel

    2009-01-01

    The primary questions addressed in this paper are the following: what are the factors that affect students' adoption of an e-learning system and what are the relationships among these factors? This paper investigates and identifies some of the major factors affecting students' adoption of an e-learning system in a university in Jordan. E-learning…

  12. Institutional and Managerial Factors Affecting International Student Recruitment Management

    ERIC Educational Resources Information Center

    Ross, Mitchell; Heaney, Joo-Gim; Cooper, Maxine

    2007-01-01

    Purpose: The purpose of this paper is to investigate international student recruitment from an institutional perspective and to consider institutional factors that may affect recruitment. Design/methodology/approach: A qualitative study is undertaken in which education marketing practitioners are interviewed regarding aspects of international…

  13. Application of Sargassum biomass to remove heavy metal ions from synthetic multi-metal solutions and urban storm water runoff.

    PubMed

    Vijayaraghavan, K; Teo, Ting Ting; Balasubramanian, R; Joshi, Umid Man

    2009-05-30

    The ability of Sargassum sp. to biosorb four metal ions, namely lead, copper, zinc, and manganese from a synthetic multi-solute system and real storm water runoff has been investigated for the first time. Experiments on synthetic multi-solute systems revealed that Sargassum performed well in the biosorption of all four metal ions, with preference towards Pb, followed by Cu, Zn, and Mn. The solution pH strongly affected the metal biosorption, with pH 6 being identified as the optimal condition for achieving maximum biosorption. Experiments at different biosorbent dosages revealed that good biosorption capacity as well as high metal removal efficiency was observed at 3g/L. The biosorption kinetics was found to be fast with equilibrium being attained within 50 min. According to the Langmuir isotherm model, Sargassum exhibited maximum uptakes of 214, 67.5, 24.2 and 20.2mg/g for lead, copper, zinc, and manganese, respectively in single-solute systems. In multi-metal systems, strong competition between four metal ions in terms of occupancy binding sites was observed, and Sargassum showed preference in the order of Pb>Cu>Zn>Mn. The application of Sargassum to remove four heavy metal ions in real storm water runoff revealed that the biomass was capable of removing the heavy metal ions. However, the biosorption performance was slightly lower compared to that of synthetic metal solutions. Several factors were responsible for this difference, and the most important factor is the presence of other contaminants such as anions, organics, and other trace metals in the runoff.

  14. Peroxotitanates for Biodelivery of Metals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hobbs, David; Elvington, M.

    2009-02-11

    Metal-based drugs are largely undeveloped in pharmacology. One limiting factor is the systemic toxicity of metal-based compounds. A solid-phase, sequestratable delivery agent for local delivery of metals could reduce systemic toxicity, facilitating new drug development in this nascent area. Amorphous peroxotitanates (APT) are ion exchange materials with high affinity for several heavy metal ions, and have been proposed to deliver or sequester metal ions in biological contexts. In the current study, we tested a hypothesis that APT are able to deliver metals or metal compounds to cells. We exposed fibroblasts (L929) or monocytes (THP1) to metal-APT materials for 72 hmore » in vitro, then measured cellular mitochondrial activity (SDH-MTT method) to assess the biological impact of the metal-APT materials vs. metals or APT alone. APT alone did not significantly affect cellular mitochondrial activity, but all metal-APT materials suppressed the mitochondrial activity of fibroblasts (by 30-65% of controls). The concentration of metal-APT materials required to suppress cellular mitochondrial activity was below that required for metals alone, suggesting that simple extracellular release of the metals from the metal-APT materials was not the primary mechanism of mitochondrial suppression. In contrast to fibroblasts, no metal-APT material had a measurable effect on THP1 monocyte mitochondrial activity, despite potent suppression by metals alone. This latter result suggested that 'biodelivery' by metal-APT materials may be cell type-specific. Therefore, it appears that APT are plausible solid phase delivery agents of metals or metal compounds to some types of cells for potential therapeutic effect.« less

  15. Psychological factors affecting medical condition: a new proposal for DSM-V.

    PubMed

    Fava, Giovanni A; Fabbri, Stefania; Sirri, Laura; Wise, Thomas N

    2007-01-01

    The DSM category of "psychological factors affecting medical condition" had virtually no impact on clinical practice. However, several clinically relevant psychosomatic syndromes have been described in the literature: disease phobia, persistent somatization, conversion symptoms, illness denial, demoralization, and irritable mood. These syndromes, in addition to the DSM definition of hypochondriasis, can yield clinical specification in the category of "psychological factors affecting medical condition" and eliminate the need for the highly criticized DSM classification of somatoform disorders. This new classification is supported by a growing body of research evidence and is in line with psychosomatic medicine as a recognized subspecialty.

  16. Higher trophic level affects nutrient, silicon, metal(loid), and radionuclide mobilization from freshwater sediments

    NASA Astrophysics Data System (ADS)

    Schaller, Jörg; Planer-Friedrich, Britta

    2017-04-01

    Organic sediments in aquatic ecosystems are well known sinks for nutrients, silicon, and metal(loid)s. Organic matter-decomposing organisms like invertebrate shredders, grazers, bioturbators, and filter feeder are key-species for the carbon and energy turnover within the decomposer community. We could show that invertebrate shredders and grazer affect element fixation or remobilization by changing binding properties of organic sediments and the attached biofilm. Bioturbators affect element fixation or remobilization by changing redox conditions within the uppermost sediment layer. Last but not least filter feeders, like the zebra mussel Dreissena polymorpha, an invasive organism in North American and European freshwater ecosystems significantly contributed to element mobilization of silicon, iron, phosphorus, arsenic, and copper and to immobilization of uranium (p<0.001), probably driven by redox conditions, microbial activity within the gut system, or active control of element homeostasis. Except of the filter feeder D. polymorpha, the invertebrates are able to minimize the accumulation of non-nutrient elements due to specific strategies, which is an important strategy for species living in systems tending to element accumulation. However, D. polymorpha revealed a significant uptake and accumulation of arsenic, copper, iron, and especially uranium both into the soft body tissues and the seashell. This accumulation by D. polymorpha is in line with previous observations of metal(loid) accumulation from biomonitoring studies. In summary, higher trophic level strongly contributes to element fixation or remobilization in aquatic systems.

  17. Demographic and obstetric factors affecting women's sexual functioning during pregnancy.

    PubMed

    Abouzari-Gazafroodi, Kobra; Najafi, Fatemeh; Kazemnejad, Ehsan; Rahnama, Parvin; Montazeri, Ali

    2015-08-19

    Sexual desire and frequency of sexual relationships during pregnancy remains challenging. This study aimed to assess factors that affect women's sexual functioning during pregnancy. This was a cross sectional study carried out at prenatal care clinics of public health services in Iran. An author-designed structured questionnaire including items on socio-demographic characteristics, obstetric history, the current pregnancy, and women's sexual functioning during pregnancy was used to collect data. The generalized linear model was performed in order to find out factors that affect women's sexual functioning during pregnancy. In all, 518 pregnant women participated in the study. The mean age of participants was 26.4 years (SD = 4.7). Overall 309 women (59.7%) scored less than mean on sexual functioning. The results obtained from generalized linear model demonstrated that that lower education, unwanted pregnancy, earlier stage of pregnancy, older age, and longer duration of marriage were the most important factors contributing to disturbed sexual functioning among couples. The findings suggest that sexual function during pregnancy might be disturbed due to several factors. Indeed issues on sexual relationship should be included as part of prenatal care and reproductive health programs for every woman.

  18. Affect and Health Behavior Co-Occurrence: The Emerging Roles of Transdiagnostic Factors and Sociocultural Factors.

    PubMed

    Zvolensky, Michael J; Leventhal, Adam M

    2016-01-01

    The majority of scientific work addressing relations among affective states and health correlates has focused primarily on their co-occurrence and a limited range of health conditions. We have developed a Special Issue to highlight recent advances in this emerging field of work that addresses the nature and interplay between affective states and disorders, in terms of their impact and consequences from health status and behavior. This Special Issue is organized into three parts classified as (a) co-occurrence and interplay between (b) transdiagnostic factors and (c) sociocultural factors. It is hoped that this issue will (a) alert readers to the significance of this work at different levels of analysis, (b) illustrate the many domains currently being explored via innovative approaches, and (c) identify fecund areas for future systematic study. © The Author(s) 2016.

  19. Prevalence, pathophysiological mechanisms and factors affecting urolithiasis.

    PubMed

    Khan, Aslam

    2018-05-01

    The formation of urinary stone, urolithiasis, is one the oldest known disease affecting human throughout different civilizations and times. The exact pathophysiological mechanism of urolithiasis is not yet clear, as these calculi are of various types and too complex for simple understanding. A single theory cannot explain its formation; therefore, different theories are presented in various times for its explanation like free particle, fixed particle, Randall's plaque theory. In addition, various factors and components are identified that play an important role in the formation of these urinary calculi. In this review, composition of kidney stones, its prevalence/incidence, explanation of pathophysiological mechanisms and role of various factors; urinary pH, uric acid, parathyroid hormone, citrate, oxalate, calcium and macromolecules; osteopontin, matrix Gla protein, kidney injury molecules, urinary prothrombin fragment-1, Tamm-Horsfall protein, inter-α-inhibitors, have been discussed in detail.

  20. The Metallicity Dependence of the CO → H2 Conversion Factor in z >= 1 Star-forming Galaxies

    NASA Astrophysics Data System (ADS)

    Genzel, R.; Tacconi, L. J.; Combes, F.; Bolatto, A.; Neri, R.; Sternberg, A.; Cooper, M. C.; Bouché, N.; Bournaud, F.; Burkert, A.; Comerford, J.; Cox, P.; Davis, M.; Förster Schreiber, N. M.; Garcia-Burillo, S.; Gracia-Carpio, J.; Lutz, D.; Naab, T.; Newman, S.; Saintonge, A.; Shapiro, K.; Shapley, A.; Weiner, B.

    2012-02-01

    We use the first systematic samples of CO millimeter emission in z >= 1 ''main-sequence'' star-forming galaxies to study the metallicity dependence of the conversion factor αCO, from CO line luminosity to molecular gas mass. The molecular gas depletion rate inferred from the ratio of the star formation rate (SFR) to CO luminosity, is ~1 Gyr-1 for near-solar metallicity galaxies with stellar masses above M S ~ 1011 M ⊙. In this regime, the depletion rate does not vary more than a factor of two to three as a function of molecular gas surface density or redshift between z ~ 0 and 2. Below M S the depletion rate increases rapidly with decreasing metallicity. We argue that this trend is not caused by starburst events, by changes in the physical parameters of the molecular clouds, or by the impact of the fundamental-metallicity-SFR-stellar mass relation. A more probable explanation is that the conversion factor is metallicity dependent and that star formation can occur in ''CO-dark'' gas. The trend is also expected theoretically from the effect of enhanced photodissociation of CO by ultraviolet radiation at low metallicity. From the available z ~ 0 and z ~ 1-3 samples we constrain the slope of the log(αCO)-log (metallicity) relation to range between -1 and -2, fairly insensitive to the assumed slope of the gas-SFR relation. Because of the lower metallicities near the peak of the galaxy formation activity at z ~ 1-2 compared to z ~ 0, we suggest that molecular gas masses estimated from CO luminosities have to be substantially corrected upward for galaxies below M S. Based on observations with the Plateau de Bure millimetre interferometer, operated by the Institute for Radio Astronomy in the Millimetre Range (IRAM), which is funded by a partnership of INSU/CNRS (France), MPG (Germany), and IGN (Spain).

  1. Factors that affect the development of nurses' competencies: a systematic review.

    PubMed

    Rizany, Ichsan; Hariyati, Rr Tutik Sri; Handayani, Hanny

    2018-02-01

    To investigate factors affecting the development of nursing competency based on a review of the literature. A systematic review was utilized. The articles were taken from the databases of Pro-Quest, ScienceDirect, SpringerLink, and Scopus. They were retrieved using the following keywords: nursing competence, nurse competencies and clinical competence. Twenty-one papers were selected. Competence development is a continuous process of improving knowledge, attitudes and skills, and is influenced by a myriad of factors. Six factors were identified that affected the development of nursing competence in our systematic review: (1) work experience, (2) type of nursing environment, (3) educational level achieved, (4) adherence to professionalism, (5) critical thinking, and (6) personal factors. Work experience and education were shown to significantly influence the development of competency of nurses. Nurse managers need to support staffing competence through ongoing education, mentoring-preceptorship training, and case-reflection-discussion teaching programs. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

  2. Li Metal Anodes and Rechargeable Lithium Metal Batteries. Springer Series in Materials Science

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Jiguang; Xu, Wu; Henderson, Wesley A.

    Lithium (Li) metal is an ideal anode material for rechargeable batteries. With the urgent need for the “next generation” rechargeable batteries, such as Li-S, Li-air batteries as well as rechargeable Li metal batteries using Li intercalation compounds as the cathode, the use of Li metal anode has attracted significant interests in recent years. Unfortunately, rechargeable batteries based on Li metal anode have not yet been commercialized mainly due to two barriers: one is the growth of Li dendrites and associated safety hazard, and another is the low Coulombic efficiency (CE) of Li cycling and associated early battery failure due tomore » Li powdering and increasing cell impedance. To have a high CE, minimum side reactions between freshly/native deposited Li and electrolyte has to be minimized. These reactions are proportional to the chemical and electrochemical activity of native Li when they are in direct contact with surrounding electrolyte. They are also proportional to the surface area of deposited Li. This means that high CE of Li deposition/stripping always related to a low surface area Li deposition and suppressed Li dendrite growth. Therefore, the enhancement of CE is a more fundamental factors controlling long term, stable cycling of Li metal anode. In this book, we will first review the general models of the dendrite growth mechanism. The effect of SEI layer on the modeling of Li dendrite growth will also be discussed. Then we will discuss various instruments/tools that are critical for the investigation of Li dendrite growth. In the Chapter 3, various factors which affect CE of Li cycling and dendrite growth will be discussed together with an emphasize on enhancement of CE. Chapter 4 of the book will discuss the specific application of Li metal anode in several key rechargeable Li metal batteries, including Li-air batteries, Li-S batteries and Li metal batteries using intercalation compounds as cathode. At last, the perspective on the future

  3. Effects of urbanization on heavy metal accumulation in surface soils, Beijing.

    PubMed

    Wang, Meie; Liu, Rui; Chen, Weiping; Peng, Chi; Markert, Bernd

    2018-02-01

    Urbanization processes affect the accumulation of heavy metals in urban soils. Effects of urbanization on heavy metal accumulation in soils were studied using Beijing as an example. It has been suggested that the ecological function of vegetation covers shifting from natural to agricultural settings and then to urban greenbelts could increase the zinc (Zn) concentrations of soils successively. The Zn concentration of urban soils was significantly correlated to the percentage of the impervious land surface at the 500m×500m spatial scale. For urban parks, the age or years since the development accounted for 80% of the variances of cadmium (Cd) and Zn in soils. The population density, however, did not affect the heavy metal distributions in urban soils. To conclude, the urban age turned out to be a notable factor in quantifying heavy metal accumulation in urban soils. Copyright © 2017. Published by Elsevier B.V.

  4. Mining-caused changes to habitat structure affect amphibian and reptile population ecology more than metal pollution.

    PubMed

    Sasaki, Kiyoshi; Lesbarrères, David; Watson, Glen; Litzgus, Jacqueline

    2015-12-01

    Emissions from smelting not only contaminate water and soil with metals, but also induce extensive forest dieback and changes in resource availability and microclimate. The relative effects of such co-occurring stressors are often unknown, but this information is imperative in developing targeted restoration strategies. We assessed the role and relative effects of structural alterations of terrestrial habitat and metal pollution caused by century-long smelting operations on amphibian and reptile communities by collecting environmental and time- and area-standardized multivariate abundance data along three spatially replicated impact gradients. Overall, species richness, diversity, and abundance declined progressively with increasing levels of metals (As, Cu, and Ni) and soil temperature (T(s)) and decreasing canopy cover, amount of coarse woody debris (CWD), and relative humidity (RH). The composite habitat variable (which included canopy cover, CWD, T(s), and RH) was more strongly associated with most response metrics than the composite metal variable (As, Cu, and Ni), and canopy cover alone explained 19-74% of the variance. Moreover, species that use terrestrial habitat for specific behaviors (e.g., hibernation, dispersal), especially forest-dependent species, were more severely affected than largely aquatic species. These results suggest that structural alterations of terrestrial habitat and concomitant changes in the resource availability and microclimate have stronger effects than metal pollution per se. Furthermore, much of the variation in response metrics was explained by the joint action of several environmental variables, implying synergistic effects (e.g., exacerbation of metal toxicity by elevated temperatures in sites with reduced canopy cover). We thus argue that the restoration of terrestrial habitat conditions is a key to successful recovery of herpetofauna communities in smelting-altered landscapes.

  5. Factors Affecting Recruitment into Child and Adolescent Psychiatry Training

    ERIC Educational Resources Information Center

    Shaw, Jon A.; Lewis, John E.; Katyal, Shalini

    2010-01-01

    Objective: The authors studied the factors affecting the recruitment into child and adolescent psychiatry training in the United States. Methods: Medical students (n = 154) and general and child and adolescent psychiatry residents (n = 111) completed a questionnaire to evaluate career choice in child psychiatry (n = 265). Results: Compared with…

  6. Factorial Kriging analysis and sources of heavy metals in soils of different land-use types in the Yangtze River Delta of Eastern China.

    PubMed

    Zhou, Jie; Feng, Ke; Li, Yinju; Zhou, Yang

    2016-08-01

    The objectives of this study are to analyse the pollution status and spatial correlation of soil heavy metals and identify natural and anthropogenic sources of these heavy metals at different spatial scales. Two hundred and twenty-four soil samples (0-20 cm) were collected and analysed for eight heavy metals (Cd, Hg, As, Cu, Pb, Cr, Zn and Ni) in soils of different land-use types in the Yangtze River Delta of Eastern China. The multivariate methods and factorial Kriging analysis were used to achieve the research objectives. The results indicated that the human and natural effects of different land-use types on the contents of soil heavy metals were different. The Cd, Hg, Cu, Pb and Zn in soils of industrial area were affected by human activities, and the pollution level of these heavy metals in this area was moderate. The Pb in soils of traffic area was affected by human activities, and eight heavy metals in soils of residential area and farmland area were affected by natural factor. The ecological risk status of eight heavy metals in soils of the whole study area was light. The heavy metals in soils showed three spatial scales (nugget effect, short range and long range). At the nugget effect and short range scales, the Cd, Hg, Cu, Pb and Zn in soils were affected by human and natural factors. At three spatial scales, the As, Cr and Ni in soils were affected by soil parent materials.

  7. Resource Efficient Metal and Material Recycling

    NASA Astrophysics Data System (ADS)

    Reuter, Markus A.; van Schaik, Antoinette

    Metals enable sustainability through their use and their recyclability. However, various factors can affect the Resource Efficiency of Metal Processing and Recycling. Some typical factors that enable Resource Efficiency include and arranged under the drivers of sustainability: Environment (Maximize Resource Efficiency — Energy, Recyclates, Materials, Water, Sludges, Emissions, Land); Economic Feasibility (BAT & Recycling Systems Simulation / Digitalization, Product vis-à-vis Material Centric Recycling); and Social — Licence to Operate (Legislation, consumer, policy, theft, manual labour.). In order to realize this primary production has to be linked systemically with typical actors in the recycling chain such as Original Equipment Manufacturers (OEMs), Recyclers & Collection, Physical separation specialists as well as process metallurgical operations that produce high value metals, compounds and products that recycle back to products. This is best done with deep knowledge of multi-physics, technology, product & system design, process control, market, life cycle management, policy, to name a few. The combination of these will be discussed as Design for Sustainability (DfS) and Design for Recycling (DfR) applications.

  8. Does Choice of Head Size and Neck Geometry Affect Stem Migration in Modular Large-Diameter Metal-on-Metal Total Hip Arthroplasty? A Preliminary Analysis

    PubMed Central

    Georgiou, CS; Evangelou, KG; Theodorou, EG; Provatidis, CG; Megas, PD

    2012-01-01

    Due to their theoretical advantages, hip systems combining modular necks and large diameter femoral heads have gradually gained popularity. However, among others, concerns regarding changes in the load transfer patterns were raised. Recent stress analyses have indeed shown that the use of modular necks and big femoral heads causes significant changes in the strain distribution along the femur. Our original hypothesis was that these changes may affect early distal migration of a modular stem. We examined the effect of head diameter and neck geometry on migration at two years of follow-up in a case series of 116 patients (125 hips), who have undergone primary Metal-on-Metal total hip arthroplasty with the modular grit-blasted Profemur®E stem combined with large-diameter heads (>36 mm). We found that choice of neck geometry and head diameter has no effect on stem migration. A multivariate regression analysis including the potential confounding variables of the body mass index, bone quality, canal fill and stem positioning revealed only a negative correlation between subsidence and canal fill in midstem area. Statistical analysis, despite its limitations, did not confirm our hypothesis that choice of neck geometry and/or head diameter affects early distal migration of a modular stem. However, the importance of correct stem sizing was revealed. PMID:23284597

  9. Does Choice of Head Size and Neck Geometry Affect Stem Migration in Modular Large-Diameter Metal-on-Metal Total Hip Arthroplasty? A Preliminary Analysis.

    PubMed

    Georgiou, Cs; Evangelou, Kg; Theodorou, Eg; Provatidis, Cg; Megas, Pd

    2012-01-01

    Due to their theoretical advantages, hip systems combining modular necks and large diameter femoral heads have gradually gained popularity. However, among others, concerns regarding changes in the load transfer patterns were raised. Recent stress analyses have indeed shown that the use of modular necks and big femoral heads causes significant changes in the strain distribution along the femur. Our original hypothesis was that these changes may affect early distal migration of a modular stem. We examined the effect of head diameter and neck geometry on migration at two years of follow-up in a case series of 116 patients (125 hips), who have undergone primary Metal-on-Metal total hip arthroplasty with the modular grit-blasted Profemur®E stem combined with large-diameter heads (>36 mm). We found that choice of neck geometry and head diameter has no effect on stem migration. A multivariate regression analysis including the potential confounding variables of the body mass index, bone quality, canal fill and stem positioning revealed only a negative correlation between subsidence and canal fill in midstem area. Statistical analysis, despite its limitations, did not confirm our hypothesis that choice of neck geometry and/or head diameter affects early distal migration of a modular stem. However, the importance of correct stem sizing was revealed.

  10. A review of affecting factors on sexual satisfaction in women.

    PubMed

    Shahhosseini, Zohreh; Gardeshi, Zeinab Hamzeh; Pourasghar, Mehdi; Salehi, Fariba

    2014-12-01

    Sex is a complex, important and sensitive issue in human being and interwoven with the whole of human existence. Given the serious changes in attitude, function and behavior in sex, the need to address sexual function, especially sexual satisfaction, is felt completely. Sexual satisfaction has a very important role in creating marital satisfaction and any defect in sexual satisfaction is significantly associated with risky sexual behaviors, serious mental illness, social crimes and ultimately divorce. The aim of this study was to explore affecting factors on sexual satisfaction in women based on an overview in scientific database. In this narrative review the researchers searched MEDLINE database, Google Scholar and Science Direct as well as Persian database like Scientific Information Database with search terms of sexual satisfaction and sexual function, restricted to English/ Persian language, during the 20 years ago. Then those articles written by renowned experts were selected. In this regard, 57 articles have been reviewed, which 30 articles related to this research have been extracted. The findings were divided in to four categories including: Demographic factors, Pathophysiological factors, Psychological factors and Sociocultural factors. Sexuality, especially sexual intimacy is sophisticated and yet elegant affair that the other persons has different definitions and different functions. Discrepancies in the results of the studies show that analysis of factors affecting sexual satisfaction regardless of the women's' sociocultural context, religious beliefs, and personal attitudes is undoubtedly inefficient, unscientific and irrational.

  11. Factors affecting yearly and monthly visits to Taipei Zoo

    NASA Astrophysics Data System (ADS)

    Su, Ai-Tsen; Lin, Yann-Jou

    2018-02-01

    This study investigated factors affecting yearly and monthly numbers of visits to Taipei Zoo. Both linear and nonlinear regression models were used to estimate yearly visits. The results of both models showed that the "opening effect" and "animal star effect" had a significantly positive effect on yearly visits, while a SARS outbreak had a negative effect. The number of years had a significant influence on yearly visits. Results showed that the nonlinear model had better explanatory power and fitted the variations of visits better. Results of monthly model showed that monthly visits were significantly influenced by time fluctuations, weather conditions, and the animal star effect. Chinese New Year, summer vacation, numbers of holidays, and animal star exhibitions increased the number of monthly visits, while the number of days with temperatures at or below 15 °C, the number of days with temperatures at or above 30 °C, and the number of rainy days had significantly negative effects. Furthermore, the model of monthly visits showed that the animal star effect could last for over two quarters. The results of this study clarify the factors affecting visits to an outdoor recreation site and confirm the importance of meteorological factors to recreation use.

  12. A Qualitative Study of Factors Affecting Morale in Psychiatry Residency Training.

    PubMed

    Caravella, Rachel A; Robinson, Lee A; Wilets, Ilene; Weinberg, Michael; Cabaniss, Deborah L; Cutler, Janis L; Kymissis, Carisa; Arbuckle, Melissa R

    2016-10-01

    Resident morale is an important yet poorly understood aspect of the residency training experience. Despite implications for program quality, resident satisfaction, patient care, and recruitment, little is known about the variables influencing this complex phenomenon. This study sought to identify important factors affecting morale in psychiatry residency training. The authors conducted four semi-structured focus groups at a moderately sized, urban, psychiatry residency program during the 2013-2014 academic year. They used qualitative data analysis techniques, including grounded theory and content analysis, to identify key themes affecting resident morale across training levels. Twenty-seven residents participated in the focus groups with equal distribution across post-graduate years (PGY) 1-4. Five major conceptual categories affecting resident morale emerged: Sense of Community, Individual Motivators, Clinical Work, Feeling Cared For, and Trust in the Administration. Morale is an important topic in residency education. The qualitative results suggest that factors related to a Sense of Community and Individual Motivators generally enhanced resident morale whereas factors related to a lack of Feeling Cared For and Trust in the Administration tended to contribute to lower morale. The authors describe the possible interventions to promote stronger program morale suggested by these findings.

  13. Recent advances in nanoscale-metal assisted biochar derived from waste biomass used for heavy metals removal.

    PubMed

    Ho, Shih-Hsin; Zhu, Shishu; Chang, Jo-Shu

    2017-12-01

    Pollution of heavy metals (HMs) is a detrimental treat to human health and need to be cleaned up in a proper way. Biochar (BC), a low-cost and "green" adsorbent, has attracted significant attention due to its considerable HMs removal capacity. In particular, nano-metals have recently been used to assist BC in improving its reactivity, surface texture and magnetism. Synthesis methods and metal precursors greatly influence the properties and structures of the nanocomposites, thereby affecting their HMs removal performance. This review presents advances in synthesis methods, formation mechanisms and surface characteristics of BC nanocomposites, along with the discussions on HMs removal mechanisms and the effects of environmental factors on HMs removal efficiency. Performance of using BC nanocomposites to remediate real HMs-containing wastewater and issues associated with its process scale-up are also discussed. This review aims to provide useful information to facilitate the development of HMs removal by nanoscale-metal assisted BC. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Factors affecting the overcrowding in outpatient healthcare

    PubMed Central

    Bahadori, Mohammadkarim; Teymourzadeh, Ehsan; Ravangard, Ramin; Raadabadi, Mehdi

    2017-01-01

    Background: The expansion of outpatient services and the desire to provide more outpatient care than inpatient care create some problems such as the overcrowding in the outpatient clinics. Given the importance of overcrowding in the outpatient clinics, this qualitative study aimed to determine the factors influencing the overcrowding in the specialty and subspecialty clinic of a teaching hospital. Materials and Methods: This was a qualitative study conducted in the specialty and subspecialty clinic of a hospital using content analysis method in the period of January to March 2014. The study population was all managers and heads of the outpatient wards. The studied sample consisted of 22 managers of the clinic wards who were selected using the purposive sampling method. The required data was collected using semi-structured interviews. The collected data was analyzed using conventional content analysis and the MAXQDA 10.0 software. Results: Three themes were identified as the main factors affecting the overcrowding including the internal positive factors, internal negative factors, and external factors. Conclusions: Despite the efforts made to eliminate overcrowding, and reduce waiting times and increase access to the services for patients, the problem of overcrowding still has remained unresolved. In addition, the use of some strategies such as clarifying the working processes of the clinic for staff and patients and the relationships between the clinic and other wards especially emergency department, as well as using a simple triage system on the patients’ arrival at the clinic are recommended. PMID:28546986

  15. Recruitment and retention: factors that affect pericyte migration

    PubMed Central

    Aguilera, Kristina Y.

    2013-01-01

    Pericytes are critical for vascular morphogenesis and contribute to several pathologies, including cancer development and progression. The mechanisms governing pericyte migration and differentiation are complex and have not been fully established. Current literature suggests that platelet-derived growth factor/platelet-derived growth factor receptor-β, sphingosine 1-phosphate/endothelial differentiation gene-1, angiopoietin-1/tyrosine kinase with immunoglobulin-like and EGF-like domains 2, angiopoietin-2/tyros-ine kinase with immunoglobulin-like and EGF-like domains 2, transforming growth factor β/activin receptor-like kinase 1, transforming growth factor β/activin receptor-like kinase 5, Semaphorin-3A/Neuropilin, and matrix metalloproteinase activity regulate the recruitment of pericytes to nascent vessels. Interestingly, many of these pathways are directly affected by secreted protein acidic and rich in cysteine (SPARC). Here, we summarize the function of these factors in pericyte migration and discuss if and how SPARC might infuence these activities and thus provide an additional layer of control for the recruitment of vascular support cells. Additionally, the consequences of targeted inhibition of pericytes in tumors and the current understanding of pericyte recruitment in pathological environments are discussed. PMID:23912898

  16. Factors Affecting Role Stress and Burnout among School Counselors

    ERIC Educational Resources Information Center

    Willingham, Wendy Elizabeth

    2009-01-01

    The purpose of this study is to determine factors affecting role stress and burnout among practicing school counselors as measured by the Maslach Burnout Inventory-Educators Survey (MBI-ES) and the Role Conflict and Ambiguity Scale. The MBI-ES utilizes three subscales to measure burnout: emotional exhaustion, depersonalization, and personal…

  17. Factors affecting species distribution predictions: A simulation modeling experiment

    Treesearch

    Gordon C. Reese; Kenneth R. Wilson; Jennifer A. Hoeting; Curtis H. Flather

    2005-01-01

    Geospatial species sample data (e.g., records with location information from natural history museums or annual surveys) are rarely collected optimally, yet are increasingly used for decisions concerning our biological heritage. Using computer simulations, we examined factors that could affect the performance of autologistic regression (ALR) models that predict species...

  18. Motivational Factors Affecting Online Learning by Japanese MBA Students

    ERIC Educational Resources Information Center

    Kikuchi, Hisayo

    2006-01-01

    In Japan, Internet based learning is still at an early stage. However, adult learners in Japanese society expect the development of flexible e-learning programs. This case study examines motivational factors affecting online learning in a Japanese and Australian MBA program, using observations, interviews and a questionnaire survey. The data were…

  19. Proposed industrial recovered materials utilization targets for the metals and metal-products industry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    1979-05-01

    The introductory chapter provides a discussion of the factors that affect the recovery and reuse of secondary materials and the competition between the primary and secondary metals industries. It discusses these industries in terms of resource characteristics, industry technology, pollution control requirements, market structure, the economics of recycling, and the issues involved in econometrically estimating scrap supply response behavior. It further presents the methodology established by DOE for the metals, textiles, rubber, and pulp and paper industries. The areas in which government policies might have a significant impact on the utilization of primary and secondary metals and on any recyclingmore » targets between now and 1987 are noted. Chapter 3 presents general profiles for the major industrial segments comprising SIC 33. The profiles include such topics as industry structure, process technology, materials and recycling flow, and future trends. Chapter 4 specifically covers the evaluation of recycling targets for the ferrous, aluminum, copper, zinc, and lead industries. (MCW)« less

  20. Analysis of extrinsic and intrinsic factors affecting event related desynchronization production.

    PubMed

    Takata, Yohei; Kondo, Toshiyuki; Saeki, Midori; Izawa, Jun; Takeda, Kotaro; Otaka, Yohei; It, Koji

    2012-01-01

    Recently there has been an increase in the number of stroke patients with motor paralysis. Appropriate re-afferent sensory feedback synchronized with a voluntary motor intention would be effective for promoting neural plasticity in the stroke rehabilitation. Therefore, BCI technology is considered to be a promising approach in the neuro-rehabilitation. To estimate human motor intention, an event-related desynchronization (ERD), a feature of electroencephalogram (EEG) evoked by motor execution or motor imagery is usually used. However, there exists various factors that affect ERD production, and its neural mechanism is still an open question. As a preliminary stage, we evaluate mutual effects of intrinsic (voluntary motor imagery) and extrinsic (visual and somatosensory stimuli) factors on the ERD production. Experimental results indicate that these three factors are not always additively interacting with each other and affecting the ERD production.

  1. New strategies in the assessment of psychological factors affecting medical conditions.

    PubMed

    Sirri, Laura; Fabbri, Stefania; Fava, Giovanni A; Sonino, Nicoletta

    2007-12-01

    In this article, we examine research that may lead to a better assessment of psychological factors affecting medical conditions. We performed a review of the psychosomatic literature using both Medline and manual searches. We selected papers that were judged to be relevant to new strategies of assessment, with particular reference to the use of the Diagnostic Criteria for Psychosomatic Research. We assessed 8 areas concerned with the assessment of psychological factors in the setting of medical disease: hypochondriasis, disease phobia, persistent somatization, conversion symptoms, illness denial, demoralization, irritable mood, and Type A behavior. A new subclassification of the Diagnostic and Statistical Manual of Mental Disorders (5th ed. [DSM-V]; not yet published) category of psychological factors affecting physical conditions appears to be feasible and may provide the clinician with better tools for identifying psychological distress.

  2. Multifactorial analysis of factors affecting recurrence of stroke in Japan.

    PubMed

    Omori, Toyonori; Kawagoe, Masahiro; Moriyama, Michiko; Yasuda, Takeshi; Ito, Yasuhiro; Hyakuta, Takeshi; Nagatsuka, Kazuyuki; Matsumoto, Masayasu

    2015-03-01

    Data on factors affecting stroke recurrence are relatively limited. The authors examined potential factors affecting stroke recurrence, retrospectively. The study participants were 1087 patients who were admitted to stroke centers suffering from first-ever ischemic stroke and returned questionnaires with usable information after discharge. The authors analyzed the association between clinical parameters of the patients and their prognosis. Recurrence rate of during an average of 2 years after discharge was 21.3%, and there were differences among stroke subtypes. It was found that the disability level of the patients after discharge correlated well with the level at discharge (r s = 0.66). Multivariate logistic regression analysis of the data shows that modified Rankin Scale score, National Institute of Health Stroke Scale score, gender, age, and family history had statistically significant impacts on stroke recurrence, and the impact was different depending on subtypes. These findings suggest that aggressive and persistent health education for poststroke patients and management of risk factors are essential to reduce stroke recurrence. © 2012 APJPH.

  3. Microstructures and Mechanical Properties of Weld Metal and Heat-Affected Zone of Electron Beam-Welded Joints of HG785D Steel

    NASA Astrophysics Data System (ADS)

    Zhang, Qiang; Han, Jianmin; Tan, Caiwang; Yang, Zhiyong; Wang, Junqiang

    2016-12-01

    Vacuum electron beam welding (EBW) process was employed to butt weld 10-mm-thick HG785D high-strength steels. The penetration into the steel was adjusted by beam current. Microstructures at weld metal and heat-affected zone (HAZ) regions were comparatively observed. Mechanical properties of the EBWed joints including Vickers hardness, tensile and Charpy impact tests were evaluated. The results indicated that microstructures at the weld metal consisted of coarse lath martensite and a small amount of acicular martensite, while that in the HAZ was tempered sorbite and martensite. The grain size in the weld metal was found to be larger than that in the HAZ, and its proportion in weld metal was higher. The hardness in the weld metal was higher than the HAZ and base metal. The tensile strength and impact toughness in the HAZ was higher than that in the weld metal. All the behaviors were related to microstructure evolution caused by higher cooling rates and state of base metal. The fracture surfaces of tensile and impact tests on the optimized joint were characterized by uniform and ductile dimples. The results differed significantly from that obtained using arc welding process.

  4. Mathematics Performance and the Role Played by Affective and Background Factors

    ERIC Educational Resources Information Center

    Grootenboer, Peter; Hemmings, Brian

    2007-01-01

    In this article, we report on a study examining those factors which contribute to the mathematics performance of a sample of children aged between 8 and 13 years. The study was designed specifically to consider the potency of a number of mathematical affective factors, as well as background characteristics (viz., gender, ethnicity, and…

  5. Factors Affecting Career Decision Making of Mexican and Mexican-American Students.

    ERIC Educational Resources Information Center

    Newlon, Betty J.; Borboa, Roman

    The purpose of this research was to identify the self-reported factors affecting the career decision making of Mexican and Mexican-American students. It was hypothesized that the factor clusters would differ between the two sample populations, Mexican and Mexican-American. It was also hypothesized that these clusters would differ from six clusters…

  6. Industry Training: The Factors that Affect Demand. Discussion Paper.

    ERIC Educational Resources Information Center

    Smith, A.; Roberts, P.; Noble, C.; Hayton, G.; Thorne, E.

    A study was conducted in Australia, to determine the factors that affect demand for job training. The study consisted of 30 detailed industry case studies, an industry analysis, and a literature review. Each case study examined current training practices, training decision making in the business, and the determinants of training for the…

  7. An Analysis of Factors Affecting Community College Students' Expectations on E-Learning

    ERIC Educational Resources Information Center

    Kilic-Cakmak, Ebru; Karatas, Sercin; Ocak, Mehmet Akif

    2009-01-01

    There are many factors that affect the e-learning process. Instructor, assessment and evaluation, communication, and technical support are among the leading factors. It is obvious that these factors influence the effectiveness of e-learning and may be related to different expectations of e-learners. Therefore, this study focuses on examining the…

  8. Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors

    PubMed Central

    Tatarinova, Tatiana; Dien Bard, Jennifer; Cohen, Irit

    2015-01-01

    Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content. PMID:26114113

  9. Lengths of Orthologous Prokaryotic Proteins Are Affected by Evolutionary Factors.

    PubMed

    Tatarinova, Tatiana; Salih, Bilal; Dien Bard, Jennifer; Cohen, Irit; Bolshoy, Alexander

    2015-01-01

    Proteins of the same functional family (for example, kinases) may have significantly different lengths. It is an open question whether such variation in length is random or it appears as a response to some unknown evolutionary driving factors. The main purpose of this paper is to demonstrate existence of factors affecting prokaryotic gene lengths. We believe that the ranking of genomes according to lengths of their genes, followed by the calculation of coefficients of association between genome rank and genome property, is a reasonable approach in revealing such evolutionary driving factors. As we demonstrated earlier, our chosen approach, Bubble-sort, combines stability, accuracy, and computational efficiency as compared to other ranking methods. Application of Bubble Sort to the set of 1390 prokaryotic genomes confirmed that genes of Archaeal species are generally shorter than Bacterial ones. We observed that gene lengths are affected by various factors: within each domain, different phyla have preferences for short or long genes; thermophiles tend to have shorter genes than the soil-dwellers; halophiles tend to have longer genes. We also found that species with overrepresentation of cytosines and guanines in the third position of the codon (GC3 content) tend to have longer genes than species with low GC3 content.

  10. A Study of the Technological, Instructional, and Motivational Factors Affecting PHR Certification Exam Outcomes

    ERIC Educational Resources Information Center

    Bonner, David M.

    2012-01-01

    Although previous studies have considered the factors affecting other certification exam outcomes, they have not examined those that are related to performance on the Professional in Human Resources (PHR) exam. In response to that need, this study specifically investigates technology and training factors that affect self-efficacy and self-set…

  11. Metal contamination of soils and crops affected by the Chenzhou lead/zinc mine spill (Hunan, China).

    PubMed

    Liu, Hongyu; Probst, Anne; Liao, Bohan

    2005-03-01

    , and rice and capsicum had high Cd concentration in the edible parts. However, the toxic element concentrations in maize, sorghum, Adzuki bean, soybean and mung bean remained lower than the threshold levels. The bio-accumulation factors (BAFs) of crops were in the order: Cd>Zn>Cu>Pb>As. BAF was typically lower in the edible seeds or fruits than in stems and leaves. The accumulation effect strongly depends on the crop's physiological properties, the mobility, of the metals, and the availability of metals in soils but not entirely on the total element concentrations in the soils. Even so, the estimated daily intake amount of Cu, Zn, Cd, and Pb from the crops grown in the affected three sites and arsenic at SZY and GYB exceeded the RDA (Recommended dietary allowance) levels. Subsequently, the crops grown in Chenzhou Pb/Zn mine waste affected area might have a hazardous effect on the consumer's health. This area still needs effective measures to cure the As, Cd, Pb, Zn and Cu contamination.

  12. Heavy metals in surface sediments of the Jialu River, China: their relations to environmental factors.

    PubMed

    Fu, Jie; Zhao, Changpo; Luo, Yupeng; Liu, Chunsheng; Kyzas, George Z; Luo, Yin; Zhao, Dongye; An, Shuqing; Zhu, Hailiang

    2014-04-15

    This work investigated heavy metal pollution in surface sediments of the Jialu River, China. Sediment samples were collected at 19 sites along the river in connection with field surveys and the total concentrations were determined using atomic fluorescence spectrometer and inductively coupled plasma optical emission spectrometer. Sediment samples with higher metal concentrations were collected from the upper reach of the river, while sediments in the middle and lower reaches had relatively lower metal concentrations. Multivariate techniques including Pearson correlation, hierarchical cluster and principal components analysis were used to evaluate the metal sources. The ecological risk associated with the heavy metals in sediments was rated as moderate based on the assessments using methods of consensus-based Sediment Quality Guidelines, Potential Ecological Risk Index and Geo-accumulation Index. The relations between heavy metals and various environmental factors (i.e., chemical properties of sediments, water quality indices and aquatic organism indices) were also studied. Nitrate nitrogen, total nitrogen, and total polycyclic aromatic hydrocarbons concentrations in sediments showed a co-release behavior with heavy metals. Ammonia nitrogen, total nitrogen, orthophosphate, total phosphate and permanganate index in water were found to be related to metal sedimentation. Heavy metals in sediments posed a potential impact on the benthos community. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. [Factors affecting residual stones after percutaneous nephrolithotomy in patients with renal calculus].

    PubMed

    Qiao, Mingzhou; Zhang, Haifang; Zhou, Chenlong

    2015-11-24

    To explore the factors affecting the residual stones after percutaneous nephrolithotomy (PCNL) in patients with renal calculus. A retrospective analysis was performed for 1 200 patients who were affected by renal calculus and treated with PCNL between Jan 2008 and May 2014 in People's Hospital of Anyang City. Among those patients, 16 were diagnosed as bilateral renal stone and had two successive operations. The size, location and number of stones, previous history of surgery, the degree of hydronephrosis, urinary infection were included in the univariate analysis. Significant factors in univariate analysis were included in the multivariate analysis to determine factors affecting stone residual. A total of 385 cases developed stone residual after surgery. The overall residual rate was 31.7%. In univariate analysis, renal pelvis combined with caliceal calculus (P=0.006), stone size larger than 4 cm (P=0.005), stone number more than 4 (P=0.002), the amount of bleeding more than 200 ml (P=0.025), operation time longer than 120 minutes (P=0.028) were associated with an increased rate of stone residual. When subjected to the Cox multivariate analysis, the independent risk factors for residual stones were renal pelvis combined with caliceal calculus (P=0.049), stone size larger than 4 cm (P=0.038) and stone number more than 4 (P=0.018). Factors affecting the incidence of residual stones after PCNL are the size, location and number of stones. Larger size stone and the presence of renal pelvis combined with caliceal calculus are significantly associated with residual stones. Nevertheless, stone number less than 4 indicates an increased stone clearance rate.

  14. Factors affecting decision-making of patients choosing acupuncture in a public hospital.

    PubMed

    Sayampanathan, Andrew Arjun; Koh, Thean Howe Bryan; Kong, Keng He; Low, Yin Peng

    2015-11-01

    With increasing evidence to support its practice, acupuncture has been integrated within many hospitals around the world. The purpose of this study is to understand the factors affecting decision making of patients as they select acupuncture treatment for their medical conditions and symptoms within a public hospital. A qualitative study consisting of in depth interviews with 14 patients was conducted. All patients attended an acupuncture clinic within a public hospital. Data collected was analysed via thematic analysis. Four main factor groups affecting decision making of patients were identified- factors affecting the level and value of patient-centric care, the confidence and trust patients place within the acupuncture service, the presence of collaborative efforts between acupuncturists and Western medicine practitioners, and the knowledge, culture and belief society has regarding the role of acupuncture and Western medicine. All participants interviewed had more than one factor group present as enablers toward their eventual selection of acupuncture for ailment management. It was also noted that although the majority of participants had sufficient knowledge regarding acupuncture, there were a select few who had misperceptions or no knowledge regarding certain aspects of acupuncture. There may be certain patterns in the way patients choose to utilise acupuncture services in public hospitals. Further studies should also be carried out in other public hospitals to analyse the factor groups identified further.

  15. Factors that Affect Poverty Areas in North Sumatera Using Discriminant Analysis

    NASA Astrophysics Data System (ADS)

    Nasution, D. H.; Bangun, P.; Sitepu, H. R.

    2018-04-01

    In Indonesia, especially North Sumatera, the problem of poverty is one of the fundamental problems that become the focus of government both central and local government. Although the poverty rate decreased but the fact is there are many people who are poor. Poverty happens covers several aspects such as education, health, demographics, and also structural and cultural. This research will discuss about several factors such as population density, Unemployment Rate, GDP per capita ADHK, ADHB GDP per capita, economic growth and life expectancy that affect poverty in Indonesia. To determine the factors that most influence and differentiate the level of poverty of the Regency/City North Sumatra used discriminant analysis method. Discriminant analysis is one multivariate analysis technique are used to classify the data into a group based on the dependent variable and independent variable. Using discriminant analysis, it is evident that the factor affecting poverty is Unemployment Rate.

  16. Factors Other than GFR Affecting Serum Cystatin C Levels

    PubMed Central

    Stevens, Lesley A; Schmid, Christopher H.; Greene, Tom; Li, Liang; Beck, Gerald J; Joffe, Marshall; Froissart, Marc; Kusek, John; Zhang, Yaping (Lucy); Coresh, Josef; Levey, Andrew S

    2015-01-01

    Cystatin C is gaining acceptance as an endogenous filtration marker. Factors other than glomerular filtration rate (GFR) that affect the serum level have not been carefully studied. In a cross-sectional analysis of a pooled dataset of participants from clinical trials and a clinical population with chronic kidney disease (N=3418), we related serum levels of cystatin C and creatinine to clinical and biochemical variables after adjustment for GFR using errors-in-variables models to account for GFR measurement error. GFR was measured as urinary clearance of 125I-iothalamate and 15Cr-EDTA. Cystatin C was assayed at a single laboratory and creatinine was standardized to reference methods. Mean (SD) creatinine and cystatin C were 2.1 (1.1) mg/dL and 1.8 (0.8) mg/L, respectively. After adjustment for GFR, cystatin C was 4.3% lower for every 20 years of age, 9.2% lower for female sex but only 1.9% lower in blacks. Diabetes was associated with 8.5% higher levels of cystatin C and 3.9% lower levels of creatinine. Higher C-reactive protein and white blood cell count and lower serum albumin were associated with higher levels of cystatin C and lower levels of creatinine. Adjustment for age, sex and race had a greater effect on association of factors with creatinine than cystatin C. In conclusion, cystatin C is affected by factors other than GFR. Clinicians should consider these factors when interpreting the serum levels or GFR estimates from cystatin C. PMID:19119287

  17. Does the Type of Metal Instrumentation Affect the Risk of Surgical Site Infection in Pediatric Scoliosis Surgery?

    PubMed

    Wright, Margaret L; Skaggs, David L; Matsumoto, Hiroko; Woon, Regina P; Trocle, Ashley; Flynn, John M; Vitale, Michael G

    2016-05-01

    Retrospective cohort study. To determine the association of implant metal composition with the risk of surgical site infection (SSI) following pediatric spine surgery. SSI is a well-described complication following pediatric spine surgery. Many risk factors have been identified in the literature, but controversy remains regarding metal composition as a risk factor. This was a retrospective study of patients who underwent posterior spinal instrumentation procedures between January 1, 2006, and December 31, 2008, at three large children's hospitals for any etiology of scoliosis and had at least 1 year of postoperative follow-up. Procedures included posterior spinal fusion, growth-friendly instrumentation, and revision of spinal instrumentation. The Centers for Disease Control and Prevention definition of SSI was used. A chi-squared test was performed to determine the relationship between type of metal instrumentation and development of an SSI. The study included 874 patients who underwent 1,156 total procedures. Overall, 752 (65%) procedures used stainless steel instrumentation, 238 (21%) procedures used titanium instrumentation, and the remaining 166 (14%) procedures used cobalt chrome and titanium hybrid instrumentation. The overall risk of infection was 6.1% (70/1,156) per procedure, with 5.9% (44/752) for stainless steel, 6.7% (12/238) for titanium, and 6.0% (10/166) for cobalt chrome. The multiple regression analysis found no significant differences in the metal type used between patients with and without infection (p = .886) adjusting for etiology, instrumentation to pelvis, and type of procedures. When stratified based on etiology, the multiple regression analyses also found no significant difference in SSI between two metal type groups. This study found no difference in risk of infection with stainless steel, titanium, or cobalt chrome/titanium instrumentation and is adequately powered to detect a true difference in risk of SSI. Level II, prognostic

  18. Validating YouTube Factors Affecting Learning Performance

    NASA Astrophysics Data System (ADS)

    Pratama, Yoga; Hartanto, Rudy; Suning Kusumawardani, Sri

    2018-03-01

    YouTube is often used as a companion medium or a learning supplement. One of the educational places that often uses is Jogja Audio School (JAS) which focuses on music production education. Music production is a difficult material to learn, especially at the audio mastering. With tutorial contents from YouTube, students find it easier to learn and understand audio mastering and improved their learning performance. This study aims to validate the role of YouTube as a medium of learning in improving student’s learning performance by looking at the factors that affect student learning performance. The sample involves 100 respondents from JAS at audio mastering level. The results showed that student learning performance increases seen from factors that have a significant influence of motivation, instructional content, and YouTube usefulness. Overall findings suggest that YouTube has a important role to student learning performance in music production education and as an innovative and efficient learning medium.

  19. Beyond Negative Pain-Related Psychological Factors: Resilience Is Related to Lower Pain Affect in Healthy Adults.

    PubMed

    Hemington, Kasey S; Cheng, Joshua C; Bosma, Rachael L; Rogachov, Anton; Kim, Junseok A; Davis, Karen D

    2017-09-01

    Resilience, a characteristic that enhances adaptation in response to stressful events, is a positive psychological factor that can predict and modulate health outcomes. However, resilience is rarely considered in pain research. Conversely, negative psychological factors (eg, anxiety, depression) are known to be related to the affective dimension of pain. It is critical to understand all potential psychological drivers of pain affect, a prominent component of chronic pain. We tested the hypothesis that higher resilience is associated with lower pain affect, above and beyond the predictive value of negative psychological factors. Healthy adults underwent psychophysical testing to acquire ratings of heat pain intensity and unpleasantness and completed the Resilience Scale, the State-Trait Anxiety Inventory (trait form), Beck Depression Inventory, Pain Catastrophizing Scale, and the Pain Vigilance and Attention Questionnaire. Multiple regression modeling (n = 68) showed resilience to be a negatively associated with pain affect (unpleasantness). Furthermore, in individuals with higher anxiety scores, resilience was protective against higher pain affect. This highlights the importance of resilience, a positive psychological factor, in the affective dimension of pain. This study is the first to assess a positive psychological factor and experimental pain affect, and has the potential to improve prediction of and treatment strategies for clinical pain. We report that resilience, a positive psychological factor, interacts with anxiety and is associated with heat pain affect (unpleasantness) in healthy individuals. Resilience may provide predictive value of chronic pain affect and treatment outcomes, and could be a target for behavioral therapy. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.

  20. A study of the factors affecting the range of airplanes

    NASA Technical Reports Server (NTRS)

    Biermann, David

    1937-01-01

    A study was made of the most important factors affecting the range of airplanes. Numerical examples are given showing the effects of different variables on the range of a two-engine airplane. The takeoff problems of long-range airplanes are analyzed.

  1. An Empirically Derived Taxonomy of Factors Affecting Physicians' Willingness to Disclose Medical Errors

    PubMed Central

    Kaldjian, Lauris C; Jones, Elizabeth W; Rosenthal, Gary E; Tripp-Reimer, Toni; Hillis, Stephen L

    2006-01-01

    BACKGROUND Physician disclosure of medical errors to institutions, patients, and colleagues is important for patient safety, patient care, and professional education. However, the variables that may facilitate or impede disclosure are diverse and lack conceptual organization. OBJECTIVE To develop an empirically derived, comprehensive taxonomy of factors that affects voluntary disclosure of errors by physicians. DESIGN A mixed-methods study using qualitative data collection (structured literature search and exploratory focus groups), quantitative data transformation (sorting and hierarchical cluster analysis), and validation procedures (confirmatory focus groups and expert review). RESULTS Full-text review of 316 articles identified 91 impeding or facilitating factors affecting physicians' willingness to disclose errors. Exploratory focus groups identified an additional 27 factors. Sorting and hierarchical cluster analysis organized factors into 8 domains. Confirmatory focus groups and expert review relocated 6 factors, removed 2 factors, and modified 4 domain names. The final taxonomy contained 4 domains of facilitating factors (responsibility to patient, responsibility to self, responsibility to profession, responsibility to community), and 4 domains of impeding factors (attitudinal barriers, uncertainties, helplessness, fears and anxieties). CONCLUSIONS A taxonomy of facilitating and impeding factors provides a conceptual framework for a complex field of variables that affects physicians' willingness to disclose errors to institutions, patients, and colleagues. This taxonomy can be used to guide the design of studies to measure the impact of different factors on disclosure, to assist in the design of error-reporting systems, and to inform educational interventions to promote the disclosure of errors to patients. PMID:16918739

  2. Factors Affecting Teen Involvement in Pennsylvania 4-H Programming

    ERIC Educational Resources Information Center

    Gill, Bart E.; Ewing, John C.; Bruce, Jacklyn A.

    2010-01-01

    The study reported here determined the factors that affect teen involvement in 4-H programming. The design of the study was descriptive and correlational in nature. Using a purposive sampling procedure, a survey questionnaire was distributed to all (N=214) 4-H members attending the 4-H State Leadership Conference. The major findings of the study…

  3. [Factors affecting the quality of cardiopulmonary resuscitation in inpatient units: perception of nurses].

    PubMed

    Citolino, Clairton Marcos Filho; Santos, Eduesley Santana; Silva, Rita de Cassia Gengo E; Nogueira, Lilia de Souza

    2015-12-01

    To identify, in the perception of nurses, the factors that affect the quality of cardiopulmonary resuscitation (CPR) in adult inpatient units, and investigate the influence of both work shifts and professional experience length of time in the perception of these factors. A descriptive, exploratory study conducted at a hospital specialized in cardiology and pneumology with the application of a questionnaire to 49 nurses working in inpatient units. The majority of nurses reported that the high number of professionals in the scenario (75.5%), the lack of harmony (77.6%) or stress of any member of staff (67.3%), lack of material and/or equipment failure (57.1%), lack of familiarity with the emergency trolleys (98.0%) and presence of family members at the beginning of the cardiopulmonary arrest assistance (57.1%) are factors that adversely affect the quality of care provided during CPR. Professional experience length of time and the shift of nurses did not influence the perception of these factors. The identification of factors that affect the quality of CPR in the perception of nurses serves as parameter to implement improvements and training of the staff working in inpatient units.

  4. Heavy metals in drinking water: Occurrences, implications, and future needs in developing countries.

    PubMed

    Chowdhury, Shakhawat; Mazumder, M A Jafar; Al-Attas, Omar; Husain, Tahir

    2016-11-01

    Heavy metals in drinking water pose a threat to human health. Populations are exposed to heavy metals primarily through water consumption, but few heavy metals can bioaccumulate in the human body (e.g., in lipids and the gastrointestinal system) and may induce cancer and other risks. To date, few thousand publications have reported various aspects of heavy metals in drinking water, including the types and quantities of metals in drinking water, their sources, factors affecting their concentrations at exposure points, human exposure, potential risks, and their removal from drinking water. Many developing countries are faced with the challenge of reducing human exposure to heavy metals, mainly due to their limited economic capacities to use advanced technologies for heavy metal removal. This paper aims to review the state of research on heavy metals in drinking water in developing countries; understand their types and variability, sources, exposure, possible health effects, and removal; and analyze the factors contributing to heavy metals in drinking water. This study identifies the current challenges in developing countries, and future research needs to reduce the levels of heavy metals in drinking water. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  6. Psychological Factor Affecting English Speaking Performance for the English Learners in Indonesia

    ERIC Educational Resources Information Center

    Haidara, Youssouf

    2016-01-01

    In every learning situation or environment, human psychology plays a significant role. English speaking is a language skill that is highly affected by human psychology. This research aimed at describing the psychological factor that affects negatively the English speaking performance for the English learners in Indonesia. A descriptive qualitative…

  7. The Key Factors Affecting Students' Individual Interest in School Science Lessons

    ERIC Educational Resources Information Center

    Cheung, Derek

    2018-01-01

    Individual interest in school science lessons can be defined as a relatively stable and enduring personal emotion comprising affective and behavioural reactions to events in the regular science lessons at school. Little research has compared the importance of different factors affecting students' individual interest in school science lessons. The…

  8. Affective changes during the postpartum period: Influences of genetic and experiential factors.

    PubMed

    Agrati, Daniella; Lonstein, Joseph S

    2016-01-01

    This article is part of a Special Issue "Parental Care". The postpartum period involves some truly transformational changes in females' socioemotional behaviors. For most female laboratory rodents and women, these changes include an improvement in their affective state, which has positive consequences for their ability to sensitively care for their offspring. There is heterogeneity among females in the likelihood of this positive affective change, though, and some women experience elevated anxiety or depression (or in rodents anxiety- or depression-related behaviors) after giving birth. We aim to contribute to the understanding of this heterogeneity in maternal affectivity by reviewing selected components of the scientific literatures on laboratory rodents and humans examining how mothers' physical contact with her infants, genetics, history of anxiety and depression and early-life and recent-life experiences contribute to individual differences in postpartum affective states. These studies together indicate that multiple biological and environmental factors beyond female maternal state shape affective responses during the postpartum period, and probably do so in an interactive manner. Furthermore, the similar capacity of some of these factors to modulate anxiety and depression in human and rodent mothers suggests cross-species conservation of mechanisms regulating postpartum affectivity. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. [Bioaccumulation and Biomagnification of Heavy Metals in Three Gorges Reservoir and Effect of Biological Factors].

    PubMed

    Wei, Li-li; Zhou, Qiong; Xie, Cong-xin; Wang, Jun; Li, Jun

    2016-01-15

    Three Gorges Reservoir (TGR) reached the maximum water level (175 m) of impoundment in Oct. 2010. In order to reveal the potential influence of the greatest water-level impoundment on the heavy metal pollution in the typical waters of TGR, the content level of trace metals ( Hg, Cd and Pb) in biota and potential biomagnification along the aquatic food chain were investigated in the main stem of TGR from July 2011 to August 2012, as well as the relationship between the trace metal concentrations of aquatic consumers (fish and aquatic invertebrate) and biological factors. Our study showed that no individual data of the three trace metals in biota exceeded the edible safety criteria of aquatic products in China and FAO. In contrast with those before the impoundment of TGR, Hg showed a little higher, while Cd and Pb exhibited a little lower level after the impoundment. Trace metals in TGR exhibited relatively lower concentrations compared with those in reservoirs in other countries. Significant correlations were found between the Cd concentration and body size (body length and body weight) of Cyprinus carpio, as well as the Hg concentration and body size (body length and body weight) of Erythroculter ilishaeformis. As for feeding habits, there was statistically significant difference between trace metal concentrations in herbivorous, planktonic, omnivorous and carnivorous fish. However, no significant difference was found between the metal concentrations in fish with different habitats (pelagic, mesopelagic and benthic). Even so, the overall trend was that fish living in benthic layer had higher heavy metal concentrations than those in pelagic and mesopelagic zones. The regression slopes of log-Hg concentration versus delta(15)N, served as an indicator of trophic magnification factor (TMF). Significant correlations (P < 0.05) were observed for Hg in the food web of TGR. TMF of Hg in TGR indicated lower level (0.046-0.066) in contrast with those in the reservoirs of

  10. Battlefield Acquired Immunogenicity to Metals Affects Orthopedic Implant Outcome

    DTIC Science & Technology

    2013-10-01

    WJ. Nickel, cobalt and chromium in consumer products: a role in allergic contact dermatitis ? Contact Dermatitis 1993;28:15-25. (13) Cramers M...of 14 (14) Fisher AA. Allergic dermatitis presumably due to metallic foreign bodies containing nickel or cobalt. Current Contact News 1977;19...metals, and a case of allergic contact dermatitis from stainless steel. Contact Dermatitis 1994;31:299-303. (29) Haudrechy P, Foussereau J, Mantout B

  11. Factors Affecting Soil Microbial Community Structure in Tomato Cropping Systems

    USDA-ARS?s Scientific Manuscript database

    Soil and rhizosphere microbial communities in agroecosystems may be affected by soil, climate, plant species, and management. We identified some of the most important factors controlling microbial biomass and community structure in an agroecosystem utilizing tomato plants with the following nine tre...

  12. Effect of cooling after welding on microstructure and mechanical properties of 12 Pct Cr steel weld metals

    NASA Astrophysics Data System (ADS)

    Cai, Guang-Jun; Andrén, Hans-Olof; Svensson, Lars-Erik

    1997-07-01

    The microstructure of three 12 pct cr steel weld metals with different nickel and nitrogen contents was studied in as-welded condition and after postweld heat treatment with and without intercooling. Tensile strength and impact toughness of the weld metals were investigated in different postweld heat treatment conditions. In weld metals heat treated without intercooling, austenite decomposed by a eutectoid reaction that resulted in M23C6 aggregates around retained δ-ferrite. Two morphologies of M2N and MN precipitates were found in a low-dislocation α-ferrite. It was concluded that these phases were also transformed from austenite. In weld metals heat treated with intercooling, M23C6 precipitates were smaller and more homogeneously distributed. Different MN precipitates were found in the tempered martensite. The fracture mode of the weld metals at room temperature was mainly transgranular cleavage with some fibrous fracture. Intercooling treatment improved Charpy impact toughness of the 12 pct Cr steel weld metals substantially. It was found that the important microstructural factors affecting the impact toughness of the weld metals which were heat treated without intercooling were the sizes of the α-ferrite grains, nonmetallic inclusions, and M23C6 aggregates. For the weld metals heat treated with intercooling, the factors which affect the toughness of the weld metals were the sizes of martensite packets and nonmetallic inclusions.

  13. Factors affecting the reproductive success of dominant male meerkats.

    PubMed

    Spong, Göran F; Hodge, Sarah J; Young, Andrew J; Clutton-Brock, Tim H

    2008-05-01

    Identifying traits that affect the reproductive success of individuals is fundamental for our understanding of evolutionary processes. In cooperative breeders, a dominant male typically restricts mating access to the dominant female for extended periods, resulting in pronounced variation in reproductive success among males. This may result in strong selection for traits that increase the likelihood of dominance acquisition, dominance retention and reproductive rates while dominant. However, despite considerable research on reproductive skew, few studies have explored the factors that influence these three processes among males in cooperative species. Here we use genetic, behavioural and demographic data to investigate the factors affecting reproductive success in dominant male meerkats (Suricata suricatta). Our data show that dominant males sire the majority of all offspring surviving to 1 year. A male's likelihood of becoming dominant is strongly influenced by age, but not by weight. Tenure length and reproductive rate, both important components of dominant male reproductive success, are largely affected by group size and composition, rather than individual traits. Dominant males in large groups have longer tenures, but after this effect is controlled, male tenure length also correlates negatively to the number of adult females in the group. Male reproductive rate also declines as the number of intra- and extra-group competitors increases. As the time spent in the dominant position and reproductive rate while dominant explain > 80% of the total variance in reproductive success, group composition thus has major implications for male reproductive success.

  14. Factors affecting the employability in people with epilepsy.

    PubMed

    Wo, Monica Chen Mun; Lim, Kheng Seang; Choo, Wan Yuen; Tan, Chong Tin

    2016-12-01

    People with epilepsy (PWE) are negatively prejudiced in their ability to work. This study aimed to examine demographic, clinical and psychological factors associated with employability in PWE. This study recruited epilepsy patients from a neurology clinic in Malaysia. Employability was measured using employment ratio, with a ratio ≥90% (ER90) classified as high employability. Basic demographic data such as age, gender, marital status, religion, education level and household income was collected. Clinical measures consisted of age of seizure onset, seizure frequency, type of epilepsy, aura, polytherapy, nocturnal seizures and seizure control. Psychological measures included Work Self-Determination Index (WSDI), Rosenberg Self-Esteem Scale (SES), and Multidimensional Scale of Perceived Social Support (MSPSS). Of 146 PWE, 64.4% had high employability. The participants were predominantly female (52%), Chinese (50.7%), single (50%), having tertiary education (55.5%) and focal epilepsy (72.6%). Clinically, only type of epilepsy was significantly correlated to employability of PWE. Employability of PWE was associated with ability to work (indicated by education level, work performance affected by seizures, ability to travel independently and ability to cope with stress at work) and family overprotection. The high employability group was found to have lower self-perceived stigma (ESS), higher self-determined motivation (WSDI), self-esteem (SES) and perceived social support (MSPSS), than the low employability group. Logistic regression analysis showed that tertiary education level (AOR 3.42, CI: 1.46-8.00), higher self-determination (WSDI, AOR 1.09, CI: 1.012-1.17), lower family overprotection (AOR 0.76, CI: 0.61-0.95), and generalised epilepsy (AOR 4.17, CI: 1.37-12.70) were significant predictors for higher employability in PWE. Ability to work (education level), clinical factor (type of epilepsy) and psychological factor (self-determined motivation and family

  15. Wetting and spreading behavior of molten brazing filler metallic alloys on metallic substrate

    NASA Astrophysics Data System (ADS)

    Kogi, Satoshi; Kajiura, Tetsurou; Hanada, Yukiakira; Miyazawa, Yasuyuki

    2014-08-01

    Wetting and spreading of molten brazing filler material are important factors that influence the brazing ability of a joint to be brazed. Several investigations into the wetting ability of a brazing filler alloy and its surface tension in molten state, in addition to effects of brazing time and temperature on the contact angle, have been carried out. In general, dissimilar-metals brazing technology and high-performance brazed joint are necessities for the manufacturing field in the near future. Therefore, to address this requirement, more such studies on wetting and spreading of filler material are required for a deeper understanding. Generally, surface roughness and surface conditions affect spreading of molten brazing filler material during brazing. Wetting by and interfacial reactions of the molten brazing filler material with the metallic substrate, especially, affect strongly the spreading of the filler material. In this study, the effects of surface roughness and surface conditions on the spreading of molten brazing filler metallic alloys were investigated. Ag-(40-x)Cu-xIn and Ag- (40-x)Cu-xSn (x=5, 10, 15, 20, 25) alloys were used as brazing filler materials. A mild-steel square plate (S45C (JIS); side: 30 mm; thickness: 3mm) was employed as the substrate. A few surfaces with varying roughness were prepared using emery paper. Brazing filler material and metallic base plate were first washed with acetone, and then a flux was applied to them. The filler, 50 mg, was placed on the center of the metallic base with the flux. A spreading test was performed under Ar gas using an electrically heated furnace, after which, the original spreading area, defined as the sessile drop area, and the apparent spreading area, produced by the capillary grooves, were both evaluated. It was observed that the spreading area decreased with increasing In and Sn content.

  16. Biomachining - A new approach for micromachining of metals

    NASA Astrophysics Data System (ADS)

    Vigneshwaran, S. C. Sakthi; Ramakrishnan, R.; Arun Prakash, C.; Sashank, C.

    2018-04-01

    Machining is the process of removal of material from workpiece. Machining can be done by physical, chemical or biological methods. Though physical and chemical methods have been widely used in machining process, they have their own disadvantages such as development of heat affected zone and usage of hazardous chemicals. Biomachining is the machining process in which bacteria is used to remove material from the metal parts. Chemolithotrophic bacteria such as Acidothiobacillus ferroxidans has been used in biomachining of metals like copper, iron etc. These bacteria are used because of their property of catalyzing the oxidation of inorganic substances. Biomachining is a suitable process for micromachining of metals. This paper reviews the biomachining process and various mechanisms involved in biomachining. This paper also briefs about various parameters/factors to be considered in biomachining and also the effect of those parameters on metal removal rate.

  17. Personal Factors that Affect the Satisfaction of Female Patients Undergoing Esthetic Suture after Typical Thyroidectomy.

    PubMed

    Kim, Hyo Young; Kim, Jung Won; Park, Jin Hyung; Kim, Jung Hun; Han, Yea Sik

    2013-07-01

    In esthetic surgery, understanding the factors that influence patient satisfaction is important for successful practice. We hypothesize that the factors that influence patient satisfaction include not only aesthetic and functional outcomes, but also personal factors such as the level of familiarity with factors affecting wound healing and expectations regarding aesthetic outcome. One hundred patients who underwent esthetic closure after thyroidectomy were included in this study. In order to evaluate the individual characteristics of the patients, a preoperative survey was administered to the patients. We estimated the patient satisfaction six months postoperatively and assessed the aesthetic and functional outcomes using the Patient and Observer Scar Assessment Scale. According to the results of correlation analysis, level of familiarity with wound healing factors had a positive correlation with satisfaction. High expectations, pain, itching, and high observer scale score had negative correlations with satisfaction. The factors that were correlated with satisfaction were included in the multiple regression analysis. Level of familiarity with wound healing factors was found to have a positive relationship with satisfaction, while itching and observer scale were found to have a negative relationship with satisfaction. After excluding 10 patients who had hypertrophic scars, only level of familiarity with wound healing factors and expectations affected satisfaction. The level of familiarity with factors affecting wound healing and expectations were found to independently affect satisfaction. Improving patients' level of familiarity with wound healing factors and reducing their expectations by providing suitable preoperative education has the potential to improve patient satisfaction.

  18. Arsenic in Drinking Water in Bangladesh: Factors Affecting Child Health

    PubMed Central

    Aziz, Sonia N.; Aziz, Khwaja M. S.; Boyle, Kevin J.

    2014-01-01

    The focus of this paper is to present an empirical model of factors affecting child health by observing actions households take to avoid exposure to arsenic in drinking water. Millions of Bangladeshis face multiple health hazards from high levels of arsenic in drinking water. Safe water sources are either expensive or difficult to access, affecting people’s individuals’ time available for work and ultimately affecting the health of household members. Since children are particularly susceptible and live with parents who are primary decision makers for sustenance, parental actions linking child health outcomes is used in the empirical model. Empirical results suggest that child health is significantly affected by the age and gender of the household water procurer. Adults with a high degree of concern for children’s health risk from arsenic contamination, and who actively mitigate their arsenic contaminated water have a positive effect on child health. PMID:24982854

  19. Adsorption of acid-extractable organics from oil sands process-affected water onto biomass-based biochar: Metal content matters.

    PubMed

    Bhuiyan, Tazul I; Tak, Jin K; Sessarego, Sebastian; Harfield, Don; Hill, Josephine M

    2017-02-01

    The impact of biochar properties on acid-extractable organics (AEO) adsorption from oil sands process-affected water (OSPW) was studied. Biochar from wheat straw with the highest ash content (14%) had the highest adsorption capacity (0.59 mg/g) followed by biochar from pulp mill sludge, switchgrass, mountain pine, hemp shives, and aspen wood. The adsorption capacity had no obvious trend with surface area, total pore volume, bulk polarity and aromaticity. The large impact of metal content was consistent with the carboxylates (i.e., naphthenate species) in the OSPW binding to the metals (mainly Al and Fe) on the carbon substrate. Although the capacity of biochar is still approximately two orders of magnitude lower than that of a commercial activated carbon, confirming the property (i.e., metal content) that most influenced AEO adsorption, may allow biochar to become competitive with activated carbon after normalizing for cost, especially if this cost includes environmental impacts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Battlefield-Acquired Immunogenicity to Metals Affects Orthopaedic Implant Outcome

    DTIC Science & Technology

    2015-10-01

    dermat itis? Contact Dermatit is 1993;28:15-25. (13) Cramers M, Lucht U. Metal sensitivity in patients treated for tibial fractures with plates of...Zitting A, Jolanki R, Tarvainen K. Nickel release from metals, and a case of allergic contact dermatitis from stainless steel. Contact Dermatit is... Dermat itis 1994;31:249-55. (30) Gawkrodger DJ. Nickel sensitivity and the implantation of orthopaedic prostheses. Contact Dermatit is 1993;28:257 -9

  1. Factors affecting physical therapists’ job satisfaction: questionnaire survey targeting first-year physical therapists

    PubMed Central

    Kota, Munetsugu; Kudo, Hiroyuki; Okita, Kazuhiko

    2018-01-01

    [Purpose] The survey aimed to clarify the factors that affect physiotherapists’ job satisfaction. [Subjects and Methods] To examine factors affecting physical therapists’ job satisfaction using a cross-sectional study with a questionnaire survey. Subjects were 193 first-year physical therapists who participated in a newcomer orientation at Hiroshima Prefectural Physical Therapy Association. The questionnaire comprised items concerning physical therapists’ satisfaction with their work, motives for becoming physical therapists, education in school, internships, the workplace, and comfort in the workplace. [Results] Subjects were divided into two groups according to their satisfaction with their occupation. The “high satisfaction” group included 157 subjects, and the group “low satisfaction” group included 36 subjects. Using logistic regression analysis, items concerning comfort in the workplace, motives for becoming physical therapists, and learning in school were analysed. [Conclusion] Factors affecting physical therapists’ job satisfaction were primarily influenced by previous experience and working conditions. PMID:29706706

  2. Factors affecting physical therapists' job satisfaction: questionnaire survey targeting first-year physical therapists.

    PubMed

    Kota, Munetsugu; Kudo, Hiroyuki; Okita, Kazuhiko

    2018-04-01

    [Purpose] The survey aimed to clarify the factors that affect physiotherapists' job satisfaction. [Subjects and Methods] To examine factors affecting physical therapists' job satisfaction using a cross-sectional study with a questionnaire survey. Subjects were 193 first-year physical therapists who participated in a newcomer orientation at Hiroshima Prefectural Physical Therapy Association. The questionnaire comprised items concerning physical therapists' satisfaction with their work, motives for becoming physical therapists, education in school, internships, the workplace, and comfort in the workplace. [Results] Subjects were divided into two groups according to their satisfaction with their occupation. The "high satisfaction" group included 157 subjects, and the group "low satisfaction" group included 36 subjects. Using logistic regression analysis, items concerning comfort in the workplace, motives for becoming physical therapists, and learning in school were analysed. [Conclusion] Factors affecting physical therapists' job satisfaction were primarily influenced by previous experience and working conditions.

  3. Factors affecting wood energy consumption by U.S. households

    Treesearch

    Nianfu Song; Francisco X. Aguilar; Stephen R. Shifley; Michael E. Goerndt

    2012-01-01

    About 23% of energy derived from woody sources in the U.S. was consumed by households, of which 70% was used by households in rural areas in 2005. We investigated factors affecting household-level wood energy consumption in the four continental U.S. regions using data from the U.S. Residential Energy Consumption Survey. To account for a large number of zero...

  4. Age affects not only metabolome but also metal toxicity in Scenedesmus quadricauda cultures.

    PubMed

    Kováčik, Jozef; Klejdus, Bořivoj; Babula, Petr; Hedbavny, Josef

    2016-04-05

    Responses of Scenedesmus quadricauda grown in vitro and differing in age (old culture-13 months, young culture-1 month) to short-term cadmium (Cd) or nickel (Ni) excess (24h) were compared. Higher age of the culture led to lower amount of chlorophylls, ascorbic acid and glutathione but higher signal of ROS. Surprisingly, sucrose was detected using DART-Orbitrap MS in both old and young culture and subsequent quantification confirmed its higher amount (ca. 3-times) in the old culture. Cd affected viability and ROS amount more negatively than Ni that could arise from excessive Cd uptake which was also higher in all treatments than in respective Ni counterparts. Surprisingly, nitric oxide was not extensively different in response to age or metals. Strong induction of phytochelatin 2 is certainly Cd-specific response while Ni also elevated ascorbate content. Krebs cycle acids were more accumulated in the young culture but they were rather elevated in the old culture (citric acid under Ni excess). We conclude that organic solid 'Milieu Bristol' medium we tested is suitable for long-term storage of unicellular green algae (also successfully tested for Coccomyxa sp. and Parachlorella sp.) and the impact of age on metal uptake may be useful for bioremediation purposes. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Factors Affecting Oxidation of Thiosalts by Thiobacilli

    PubMed Central

    Silver, M.; Dinardo, O.

    1981-01-01

    The effects of temperature, initial pH, and the concentrations of ammonium, phosphate, and heavy metals on the oxidation of thiosalts by an authentic strain of Thiobacillus thiooxidans (ATCC 8085) and by a mixed culture isolated from a base metal-processing mill effluent pond were studied. The optimum temperature was 30°C and the optimum initial pH was 3.75 for both cultures using thiosulfate and for the mixed culture using tetrathionate. T. thiooxidans ATCC 8085 did not oxidize tetrathionate. For a thiosalt concentration of 2,000 ppm (2,000 mg/liter), maximal rates of destruction occurred at concentrations of ammonium ion above 2 mg/liter and in the presence of 1 mg of phosphate per liter. Under optimal conditions, the rate of thiosulfate oxidation by the pure culture was 55 ± 3 mg/liter per h; the mixed culture oxidized thiosulfate at the rate of 40 ± 1 mg/liter per h and tetrathionate at the rate of 50 ± 2 mg/liter per h. Metal ions caused normal inhibition kinetics in the oxidation of thiosulfate by T. thiooxidans ATCC 8085. Ki values were calculated for cadmium (16 mg/liter), copper (0.46 mg/liter), lead (2 mg/liter), silver (3.1 mg/liter), and zinc (33 mg/liter). Only a slight additive effect was apparent in the presence of all of these metal ions. The mixed culture of thiosalt-oxidizing bacteria was less sensitive to heavy metal inhibition; the order of inhibition of thiosulfate oxidation was Cd < Zn < Pb < Ag < Cu, and that of tetrathionate oxidation was Zn < Cd < Pb < Ag < Cu. PMID:16345785

  6. Field reconnaissance and estimation of petroleum hydrocarbon and heavy metal contents of soils affected by the Ebocha-8 oil spillage in Niger Delta, Nigeria.

    PubMed

    Osuji, Leo C; Onojake, Chukunedum M

    2006-04-01

    Field reconnaissance of the Ebocha-8 oil spill-affected site at Obiobi/Obrikom in the Niger Delta region of Nigeria was carried out to assess the extent of damage to the terrestrial ecosystem and delimit the epicenter of oil spillage. Following three successive reconnaissance surveys, the area to be sampled was delimited (200 x 200 m2), and soil samples were collected using the grid method from three replicate quadrats at two depths, surface (0-15 cm) and subsurface (15-30 cm). A geographically similar area located 50 m adjacent to the oil-polluted area was used as a reference (control) site. Total hydrocarbon content (THC) and heavy metal concentrations were later determined in the laboratory by extraction and spetrophotemetric techniques. Generally, the THC of soils at surface and subsurface depths of the oil-polluted plots was 2.06 x 10(4) +/- 4.97 x 10(3) mg/kg and 1.67 x 10(3) +/- 3.61 x 10(2) mg/kg soil, respectively, (no overlap in standard errors at 95% confidence limit) while concentrations of heavy metals(Pb, Cd, V, Cu and Ni) were enhanced, especially at the surface. The high levels of THC and heavy metals may predispose the site, which hitherto served as arable agricultural land, to impaired fertility and possible conflagration. When concentrations of heavy metals reach the levels obtained in this study, they may become toxic to plants or possibly bio-accumulate, thus leading to toxic reactions along the food chain. While the spilled-oil may have contributed to the enhanced levels of the metals in the affected soils, physico-chemical properties of the soils, mobility of metals, and the intense rainfall and flooding that preceded the period of study may have also contributed in part to their enhanced concentrations. The presence of high hydrocarbon content may cause oxygen deprivation, which may result in the death of soil fauna by asphyxiation. There is, therefore, an urgent need to clear the affected site of these excess hydrocarbon deposits so as to

  7. The main factor affecting the competitiveness of Contractor Company

    NASA Astrophysics Data System (ADS)

    Nurisra; Malahayati, Nurul; Mahmuddin

    2018-05-01

    Contractor companies must have the competitive advantage to compete in maintaining the survival of the company. Problems arise because quite a lot of advantages can be used and these advantages must be used appropriately to produce competitiveness for the company to continue to compete and to win the competition. This study aims to determine the main factors affecting the competitiveness of medium-class contractors in Banda Aceh. Data collection was obtained through questionnaires distributed to 31 middle-class contractors in Banda Aceh. Data processing and analysis is done by using descriptive analysis. Based on the result of descriptive analysis, it can be concluded that the most important competitiveness factor with a mean score value 4.52 is the relationship, and the factor that has the highest mean score value is the relationship with the government of 4.97, while the result of the ranking analysis is obtained 25 factor that is critical to the competitiveness of medium-class contractors in Banda Aceh.

  8. Impacts of geochemical and environmental factors on seasonal variation of heavy metals in a coastal lagoon Yucatan, Mexico.

    PubMed

    Arcega-Cabrera, F; Garza-Pérez, R; Noreña-Barroso, E; Oceguera-Vargas, I

    2015-01-01

    This study investigated the influence of geochemical and environmental factors on seasonal variation in metals in Yucatan's Chelem lagoon. Anthropogenic activities discharge non-treated wastewater directly into it with detrimental environmental consequences. Accordingly, this study established the spatial and temporal patterns of fine grain sediments and concentrations of heavy metals. Multivariate analyses showed fine grain facies deposition, transition sites dominated by fine grain transport, and fine grain erosion sites. Spatial and temporal variations of heavy metals concentration were significant for Cd, Cu, Cr, and Pb. As, Cd, and Sn were as much as 12 times higher than SQuiRTs standards (Buchman 2008). The results indicate that aquifer water is bringing metals from relatively far inland and releasing them into the lagoon. Thus, it appears that the contamination of this lagoon is highly complex and must take into account systemic connections with inland anthropogenic activates and pollution, as well as local factors.

  9. Heavy metals (Pb, Cd, As and MeHg) as risk factors for cognitive dysfunction: A general review of metal mixture mechanism in brain.

    PubMed

    Karri, Venkatanaidu; Schuhmacher, Marta; Kumar, Vikas

    2016-12-01

    Human exposure to toxic heavy metals is a global challenge. Concurrent exposure of heavy metals, such as lead (Pb), cadmium (Cd), arsenic (As) and methylmercury (MeHg) are particularly important due to their long lasting effects on the brain. The exact toxicological mechanisms invoked by exposure to mixtures of the metals Pb, Cd, As and MeHg are still unclear, however they share many common pathways for causing cognitive dysfunction. The combination of metals may produce additive/synergetic effects due to their common binding affinity with NMDA receptor (Pb, As, MeHg), Na + - K + ATP-ase pump (Cd, MeHg), biological Ca +2 (Pb, Cd, MeHg), Glu neurotransmitter (Pb, MeHg), which can lead to imbalance between the pro-oxidant elements (ROS) and the antioxidants (reducing elements). In this process, ROS dominates the antioxidants factors such as GPx, GS, GSH, MT-III, Catalase, SOD, BDNF, and CERB, and finally leads to cognitive dysfunction. The present review illustrates an account of the current knowledge about the individual metal induced cognitive dysfunction mechanisms and analyse common Mode of Actions (MOAs) of quaternary metal mixture (Pb, Cd, As, MeHg). This review aims to help advancement in mixture toxicology and development of next generation predictive model (such as PBPK/PD) combining both kinetic and dynamic interactions of metals. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Factors Affecting the Formation of Food Preferences in Preschool Children.

    ERIC Educational Resources Information Center

    Alles-White, Monica L.; Welch, Patricia

    1985-01-01

    Identifies and discusses factors that affect the development of food preferences in preschool children, including familiarity, age, parents, peers, teachers, and programs designed to influence food habits. Makes recommendations to preschool and day care programs for creating an atmosphere conducive to trying new foods. (Author/DST)

  11. Risk factors for injuries in landslide- and flood-affected populations in Uganda.

    PubMed

    Agrawal, Shreya; Gopalakrishnan, Tisha; Gorokhovich, Yuri; Doocy, Shannon

    2013-08-01

    The frequency of occurrence of natural disasters has increased over the past several decades, which necessitates a better understanding of human vulnerability, particularly in low-resource settings. This paper assesses risk factors for injury in the March 2010 floods and landslides in Eastern Uganda, and compares the effects of location, injury type, and severity. A stratified cluster survey of the disaster-affected populations was conducted five months after onset of the disasters. Probability proportional to size sampling was used to sample 800 households, including 400 affected by floods in Butaleja District and 400 affected by landslides in Bududa District. Flood- and landslide-affected populations were surveyed in July 2010 using a stratified cluster design. The odds of injury were 65% higher in the flood-affected groups than the landslide-affected groups in a logistic regression (OR = 0.35; 95% CI, 0.24-0.52; P < .001). The injury rate was greater in individuals under 42 years of age, and location of injury was a contributing factor. More people were injured in the flood-affected population as compared with the landslide-affected population, and injuries were more severe. This study illustrates differences between populations injured by flood and landslide disasters that occurred simultaneously in Eastern Uganda in 2010. In areas where landslides are prone to occur due to massive rainfalls or floods, preventative measures, such as early warning systems and evacuation, are more likely to increase the likelihood of people surviving, while for areas with massive floods, immediate and effective medical attention can save lives and improve injury outcomes.

  12. Factors affecting smoking in schizophrenia.

    PubMed

    Beratis, S; Katrivanou, A; Gourzis, P

    2001-01-01

    There is an increased frequency of smoking among patients with schizophrenia. However, it is unknown whether the smoking behavior of the patients is similar in all schizophrenia subtypes, as well as which is the relationship between smoking initiation and disease onset. Four hundred six patients with DSM-IV schizophrenia were interviewed to determine the smoking status in relationship to gender and schizophrenic subtype, and to other factors that could affect or be affected by smoking. The frequency of smoking among patients (58%) was significantly greater than in subjects from the general population (42%) (P =.000005). Male patients smoked significantly more frequently (70%) than the corresponding control subjects (50%) (P =.000006), whereas the difference failed to reach significance between female patients (41%) and control subjects (32%). Among male patients, the number of smokers was significantly greater than in the controls in the paranoid (77%), undifferentiated (72%), and residual (78%) subtypes, whereas there was no significant difference in the disorganized (44%) and catatonic (22%) subtypes. The findings show that the frequency of smoking in schizophrenia patients increases with increasing positive symptoms and decreases with increasing negative symptoms. Male and female smoking patients consumed approximately 10 cigarettes per day more than the corresponding control subjects (P <.000001). In 86% of the patients, smoking initiation occurred before the disease onset. Among patients who smoked, smoking initiation and disease onset occurred at age 18.7 +/- 4.4 and 24.1 +/- 6.1 years, respectively (P <.000001). It appears that smoking in schizophrenia is influenced by gender and subtype. However, the nature of this association remains uncertain because in the vast majority of the patients smoking initiation occurs earlier than the disease onset. Copyright 2001 by W.B. Saunders Company

  13. Companion of choice at birth: factors affecting implementation.

    PubMed

    Kabakian-Khasholian, Tamar; Portela, Anayda

    2017-08-31

    Two recent recommendations made by the World Health Organization confirm the benefits of companion of choice at birth on labour outcomes; however institutional practices and policies do not always support its implementation in different settings around the world. We conducted a review to determine factors that affect implementation of this intervention considering the perspectives and experiences of different stakeholders and other institutional, systemic barriers and facilitators. Forty one published studies were included in this review. Thirty one publications were identified from a 2013 Cochrane review on the effectiveness of companion of choice at birth. We also reviewed 10 qualitative studies conducted alongside the trials or other interventions on labour and birth companionship identified through electronic searches. The SURE (Supporting the Use of Research Evidence) framework was used to guide the thematic analysis of implementation factors. Women and their families expressed appreciation for the continuous presence of a person to provide support during childbirth. Health care providers were concerned about the role of the companion and possible interference with activities in the labour ward. Allocation of resources, organization of care, facility-related constraints and cultural inclinations were identified as implementation barriers. Prior to introducing companion of choice at birth, understanding providers' attitudes and sensitizing them to the evidence is necessary. The commitment of the management of health care facilities is also required to change policies, including allocation of appropriate physical space that respects women's privacy. Implementation research to develop models for different contexts which could be scaled up would be useful, including documentation of factors that affected implementation and how they were addressed. Future research should also focus on documenting the costs related to implementation, and on measuring the impact of

  14. Prediction of transmittance spectra for transparent composite electrodes with ultra-thin metal layers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Zhao; Alford, T. L., E-mail: TA@asu.edu; Khorasani, Arash Elhami

    2015-11-28

    Recent interest in indium-free transparent composite-electrodes (TCEs) has motivated theoretical and experimental efforts to better understand and enhance their electrical and optical properties. Various tools have been developed to calculate the optical transmittance of multilayer thin-film structures based on the transfer-matrix method. However, the factors that affect the accuracy of these calculations have not been investigated very much. In this study, two sets of TCEs, TiO{sub 2}/Au/TiO{sub 2} and TiO{sub 2}/Ag/TiO{sub 2}, were fabricated to study the factors that affect the accuracy of transmittance predictions. We found that the predicted transmittance can deviate significantly from measured transmittance for TCEs thatmore » have ultra-thin plasmonic metal layers. The ultrathin metal layer in the TCE is typically discontinuous. When light interacts with the metallic islands in this discontinuous layer, localized surface plasmons are generated. This causes extra light absorption, which then leads to the actual transmittance being lower than the predicted transmittance.« less

  15. Biotic ligand modeling approach: Synthesis of the effect of major cations on the toxicity of metals to soil and aquatic organisms.

    PubMed

    Ardestani, Masoud M; van Straalen, Nico M; van Gestel, Cornelis A M

    2015-10-01

    The biotic ligand model (BLM) approach is used to assess metal toxicity, taking into account the competition of other cations with the free metal ions for binding to the biotic ligand sites of aquatic and soil organisms. The bioavailable fraction of metals, represented by the free metal ion, is a better measure than the total concentration for assessing their potential risk to the environment. Because BLMs are relating toxicity to the fraction of biotic ligands occupied by the metal, they can be useful for investigating factors affecting metal bioaccumulation and toxicity. In the present review, the effects of major cations on the toxicity of metals to soil and aquatic organisms were comprehensively studied by performing a meta-analysis of BLM literature data. Interactions at the binding sites were shown to be species- and metal-specific. The main factors affecting the relationships between toxicity and conditional binding constants for metal binding at the biotic ligand appeared to be Ca(2+) , Mg(2+) , and protons. Other important characteristics of the exposure medium, such as levels of dissolved organic carbon and concentrations of other cations, should also be considered to obtain a proper assessment of metal toxicity to soil and aquatic organisms. © 2015 SETAC.

  16. The Synergistic Effect of Affective Factors on Student Learning Outcomes

    ERIC Educational Resources Information Center

    Jack, Brady Michael; Lin, Huann-shyang; Yore, Larry D.

    2014-01-01

    This study investigates how affective and self-related factors impact participation in science learning and environmental awareness and responsibility. Using PISA 2006 datasets from Taiwan and Canada having similar level of science competency, the model for this study verifies and expands an earlier model by examining the relationships among…

  17. Factors Affecting Educational Innovation with in Class Electronic Response Systems

    ERIC Educational Resources Information Center

    Freeman, Mark; Bell, Amani; Comerton-Forde, Carole; Pickering, Joanne; Blayney, Paul

    2007-01-01

    This paper reports the use of Rogers' diffusion of innovation perspective to understand the factors affecting educational innovation decisions, specifically in regard to in class electronic response systems. Despite decreasing costs and four decades of research showing strong student support, academic adoption is limited. Using data collected from…

  18. Scrutinizing the Factors Affecting Fluency of English among Arab Learners

    ERIC Educational Resources Information Center

    Al Ghazali, Fawzi

    2017-01-01

    This research study investigates the cognitive, psychological and personal factors affecting the accuracy and fluency of English language usage among Arab learners. Early research led by Chomsky (1965) and Krashen (1981) suggested that an individual's Language Acquisition Device once triggered at the appropriate time and supported with adequate…

  19. Factors Affecting the Acceptability of Microforms as a Reading Medium.

    ERIC Educational Resources Information Center

    Spencer, Herbert; Reynolds, Linda

    Based on visits to representative microform users and an extensive survey of relevant literature, a study was undertaken to assess the relative importance of factors affecting the acceptability of microforms as reading mediums. The following variables were considered: (1) microform characteristics; (2) equipment design; (3) work station design;…

  20. Environmental factors affecting understory diversity in second-growth deciduous forests

    Treesearch

    Cynthia D. Huebner; J.C. Randolph; G.R. Parker

    1995-01-01

    The purpose of this study was to determine the most important nonanthropogenic factors affecting understory (herbs, shrubs and low-growing vines) diversity in forested landscapes of southern Indiana. Fourteen environmental variables were measured for 46 sites. Multiple regression analysis showed significant positive correlation between understory diversity and tree...

  1. Factors Affecting School Choice: What Do Malaysian Chinese Parents Want?

    ERIC Educational Resources Information Center

    Siah, Poh Chua; Christina Ong, Sook Beng; Tan, Swee Mee; Sim, Chzia Poaw; Xian Thoo, Raphael Yi

    2018-01-01

    Aiming to explore factors affecting Malaysian Chinese parents in sending their children to either national secondary schools or Chinese independent schools, 494 parents were surveyed using a questionnaire. Results showed that parents who sent their children to Chinese independent schools have different priorities compared to those who sent theirs…

  2. Risk factors affecting human traumatic tympanic membrane perforation regeneration therapy using fibroblast growth factor-2.

    PubMed

    Lou, Zhengcai; Yang, Jian; Tang, Yongmei; Xiao, Jian

    2015-01-01

    The use of growth factors to achieve closure of human traumatic tympanic membrane perforations (TMPs) has recently been demonstrated. However, pretreatment factors affecting healing outcomes have seldom been discussed. The objective of this study was to evaluate pretreatment factors contributing to the success or failure of healing of TMPs using fibroblast growth factor-2 (FGF-2). A retrospective cohort study of 99 patients (43 males, 56 females) with traumatic TMPs who were observed for at least 6 months after FGF-2 treatment between March 2011 and December 2012. Eleven factors considered likely to affect the outcome of perforation closure were evaluated statistically using univariate and multivariate logistic regression analysis. Each traumatic TMP was treated by direct application of FGF-2. Complete closure versus failure to close. In total, 99 patients were analyzed. The total closure rate was 92/99 (92.9%) at 6 months; the mean closure time was 10.59 ±  6.81 days. The closure rate did not significantly differ between perforations with or without inverted edges (100.0% vs. 91.4%, p = 0.087), among different size groups (p = 0.768), or among different periods of exposure to injury (p = 0.051). However, the closure rate was significantly different between the high- and low-dose FGF-2 groups (85.0% vs. 98.3%, p = 0.010) and between perforations where the umbo or malleus was or was not involved in perforation (85.4% vs. 98.3%, p = 0.012). Additionally, univariate logistic regression analysis tests showed that it was difficult to achieve healing of these perforations with a history of chronic otitis media or residual TM calcification (p = 0.006), the umbo or malleus was involved in perforation (p = 0.038), and with a high dose of FGF-2 (p = 0.035) compared with control groups. Multivariate logistic regression analysis showed that only a history of chronic otitis media and residual TM calcification and perforation close to the

  3. Factors affecting alkali jarosite precipitation

    NASA Astrophysics Data System (ADS)

    Dutrizac, J. E.

    1983-12-01

    Several factors affecting the precipitation of the alkali jarosites (sodium jarosite, potassium jarosite, rubidium jarosite, and ammonium jarosite) have been studied systematically using sodium jarosite as the model. The pH of the reacting solution exercises a major influence on the amount of jarosite formed, but has little effect on the composition of the washed product. Higher temperatures significantly increase the yield and slightly raise the alkali content of the jarosites. The yield and alkali content both increase greatly with the alkali concentration to about twice the stoichiometric requirement but, thereafter, remain nearly constant. At 97 °C, the amount of product increases with longer retention times to about 15 hours, but more prolonged reaction times are without significant effect on the amount or composition of the jarosite. Factors such as the presence of seed or ionic strength have little effect on the yield or jarosite composition. The amount of precipitate augments directly as the iron concentration of the solution increases, but the product composition is nearly independent of this variable. A significant degree of agitation is necessary to suspend the product and to prevent the jarosite from coating the apparatus with correspondingly small yields. Once the product is adequately suspended, however, further agitation is without significant effect. The partitioning of alkali ions during jarosite precipitation was ascertained for K:Na, Na:NH4, K:NH4, and K:Rb. Potassium jarosite is the most stable of the alkali jarosites and the stability falls systematically for lighter or heavier congeners; ammonium jarosite is slightly more stable than the sodium analogue. Complete solid solubility among the various alkali jarosite-type compounds was established.

  4. Partial structure factors reveal atomic dynamics in metallic alloy melts

    NASA Astrophysics Data System (ADS)

    Nowak, B.; Holland-Moritz, D.; Yang, F.; Voigtmann, Th.; Kordel, T.; Hansen, T. C.; Meyer, A.

    2017-07-01

    We investigate the dynamical decoupling of the diffusion coefficients of the different components in a metallic alloy melt, using a combination of neutron diffraction, isotopic substitution, and electrostatic levitation in Zr-Ni melts. We show that excess Ni atoms can diffuse more freely in a background of saturated chemical interaction, causing their dynamics to become much faster and thus decoupled than anticipated from the interparticle interactions. Based on the mode-coupling theory of the glass transition, the averaged structure as given by the partial static structure factors is able to explain the observed dynamical behavior.

  5. [Phosphorus availability in cropland soils of China and related affecting factors].

    PubMed

    Wang, Yong-Zhuang; Chen, Xin; Shi, Yi

    2013-01-01

    Soil phosphorus (P) availability directly determines cropland productivity. Based on the long-term fertilization experiments in different climatic zones of China, this paper summarized the P content, its availability, and the factors affecting the P transformation in China cropland soils. The total and available P contents in different types of China cropland soils were 0.31-1.72 g x kg(-1) and 0.1-228.8 mg x kg(-1), respectively. Soil parent material, soil physical and chemical prosperities, and fertilization practices were the main factors affecting the soil P availability. It was suggested that more attentions should be paid on the mixed application of organic manure and chemical fertilizers to improve the P availability of cropland soils and on the potential environmental impacts of this fertilization.

  6. Factors affecting workplace bullying and lateral violence among clinical nurses in Korea: descriptive study.

    PubMed

    Oh, Hyunjin; Uhm, Dong Choon; Yoon, Young Joo

    2016-04-01

    Workplace bullying and lateral violence are serious issues affecting the work life of hospital nurses. The purpose of this study was to identify the selected individual and institutional characteristics for workplace bullying and lateral violence using a conceptual framework. A descriptive survey design was used. A convenience sample of 255 nurses in tertiary hospitals, who had a minimum of 6 months clinical experience, completed the survey. Regression analysis was used to determine factors significantly associated with workplace bullying and lateral violence. The Negative Acts Questionnaire-Revised and the Lateral Violence scale were used to measure workplace bullying and lateral violence. A negative affect, individualism and working in hospital specialty units predicted workplace bullying. Individualism, a negative affect, affiliated hospital and working hours predicted verbal abuse whereas the place of employment was significantly associated with lateral violence. The results of this study identified factors that are associated with bullying and violence but did not fully support the conceptual framework. The individual characteristic negative affect was significantly associated with most types of workplace bullying and lateral violence bully whereas the place of employment was an important factor in lateral violence. Nurse managers need to be aware that both individual and institutional factors may impact levels of workplace bullying and lateral violence in their hospitals and need to prepare specific strategies to address these multiple factors. © 2015 John Wiley & Sons Ltd.

  7. Factors affecting length of stay in teaching hospitals of a middle-income country

    PubMed Central

    Khosravizadeh, Omid; Vatankhah, Soudabeh; Bastani, Peivand; Kalhor, Rohollah; Alirezaei, Samira; Doosty, Farzane

    2016-01-01

    Introduction The length of stay (LOS) in hospitals is a widely used and important criteria for evaluating hospital performance. The aim of this study was to determine factors affecting LOS in teaching hospitals of Qazvin Providence. Methods In this cross-sectional study, patients’ health records were randomly selected from archives in teaching hospitals of Qazvin in 2013. Data were collected through a data entry form and were analyzed using Kolmogorov–Smirnov, Kruskal–Wallis, and Mann–Whitney U tests at the significant level of 0.05. Results The mean of hospital LOS was 5.45 ± 6.14 days. Age, employment, marital status, history of previous admission, patient condition at discharge, method of payment, and type of treatment had an impact on LOS (p<0.05). Other factors, including gender, place of residence, and type of admission, did not affect LOS. Conclusion Because hospitals consume a perceptible part of resources in a health system, controlled and optimized use of its resources help to save a lot. Therefore, this study showed many clinical and nonclinical factors affect LOS in evaluating these factors, which may reduce inappropriate hospital stays and decrease costs. PMID:27957301

  8. Analysis of usability factors affecting purchase intention in online e-commerce sites

    NASA Astrophysics Data System (ADS)

    Perdana, R. A.; Suzianti, A.

    2017-03-01

    The growing number of internet users plays a significant role in the emergence of a variety of online e-commerce sites to meet the needs of Indonesians. However, there are still some problems faced by the users in using e-commerce sites. Therefore, a research related to user experience on their purchase intention to foster e-commerce sites is required. This study is conducted to find out the relationship between usability factors on e-commerce users’ purchase intention using a case study by using SEM to analyse the usability of the website. The result of this study shows that credibility, readability and telepresence are usability factors that directly affect purchase intention, while simplicity, consistency and interactivity are usability factors that indirectly affect purchase intention. Therefore, we can conclude that Indonesian consumers are on the Early Majority phase in adopting Company A.

  9. The Internal Structure of Positive and Negative Affect: A Confirmatory Factor Analysis of the PANAS

    ERIC Educational Resources Information Center

    Tuccitto, Daniel E.; Giacobbi, Peter R., Jr.; Leite, Walter L.

    2010-01-01

    This study tested five confirmatory factor analytic (CFA) models of the Positive Affect Negative Affect Schedule (PANAS) to provide validity evidence based on its internal structure. A sample of 223 club sport athletes indicated their emotions during the past week. Results revealed that an orthogonal two-factor CFA model, specifying error…

  10. Metal-on-Metal Hip Retrieval Analysis: A Case Report

    PubMed Central

    Pace, Thomas B.; Rusaw, Kara A.; Minette, Lawrence J.; Shirley, Brayton R.; Snider, Rebecca G.; DesJardins, John D.

    2013-01-01

    This is a case report involving a single case with severe bone and soft tissue destruction in a young male patient with a 10-year-metal on-metal total hip arthroplasty. Following complete aseptic erosion of the affected hip greater trochanter and abductor muscles, the hip was revised for recurrent instability. Histological examination of the patient's periprosthetic tissues, serological studies, and review of recent medical reports of similar cases were used to support an explanation of the destructive process and better contribute to our understanding of human reaction to metal debris in some patients following metal-on-metal hip arthroplasty. PMID:23840999

  11. Factors affecting midwives' confidence in intrapartum care: a phenomenological study.

    PubMed

    Bedwell, Carol; McGowan, Linda; Lavender, Tina

    2015-01-01

    midwives are frequently the lead providers of care for women throughout labour and birth. In order to perform their role effectively and provide women with the choices they require midwives need to be confident in their practice. This study explores factors which may affect midwives' confidence in their practice. hermeneutic phenomenology formed the theoretical basis for the study. Prospective longitudinal data collection was completed using diaries and semi-structured interviews. Twelve midwives providing intrapartum care in a variety of settings were recruited to ensure a variety of experiences in different contexts were captured. the principal factor affecting workplace confidence, both positively and negatively, was the influence of colleagues. Perceived autonomy and a sense of familiarity could also enhance confidence. However, conflict in the workplace was a critical factor in reducing midwives' confidence. Confidence was an important, but fragile, phenomenon to midwives and they used a variety of coping strategies, emotional intelligence and presentation management to maintain it. this is the first study to highlight both the factors influencing midwives' workplace confidence and the strategies midwives employed to maintain their confidence. Confidence is important in maintaining well-being and workplace culture may play a role in explaining the current low morale within the midwifery workforce. This may have implications for women's choices and care. Support, effective leadership and education may help midwives develop and sustain a positive sense of confidence. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Specifying the non-specific factors underlying opioid analgesia: Expectancy, attention, and affect

    PubMed Central

    Atlas, Lauren Y.; Wielgosz, Joseph; Whittington, Robert A.; Wager, Tor D.

    2013-01-01

    Rationale Psychological processes such as expectancy, attention, and affect directly influence clinical outcomes. These factors are grouped together as “nonspecific” factors, or placebo effects, in the medical literature, and their individual contributions are rarely considered. The pain-reducing effects of analgesic treatments may reflect changes in these psychological factors, rather than pure drug effects on pain. Furthermore, drug effects may not be isolated by drug vs. placebo comparisons if drugs interact with relevant psychological processes. Objectives To determine whether the analgesic effects of opioid and placebo treatment are mediated by changes in attention, expectancy, or affect. Methods We crossed intravenous administration of a potent opioid analgesic, remifentanil, with information about drug delivery (treatment expectancy, or placebo) using a balanced placebo design. We measured drug and treatment expectancy effects on pain, attention, and responses to emotional images. We also examined interactions with cue-based expectations about noxious stimulation, or stimulus expectancy. Results Pain was additively influenced by treatment expectancy, stimulus expectancy, and drug concentration. Attention performance showed a small but significant interaction between drug and treatment expectancy. Finally, remifentanil enhanced responses to both positive and negative emotional images. Conclusions The pain-relieving effects of opioid drugs are unlikely to be mediated by changes in threat or affective processing. Standard open-label opioid administration influences multiple clinically relevant cognitive and emotional processes. Psychological factors can combine with drug effects to influence multiple outcomes in distinct ways. The influence of specific psychological factors should be considered when developing and testing pharmacological treatments. PMID:24096537

  13. Variations in Heavy Metals Across Urban Streams

    NASA Astrophysics Data System (ADS)

    Kaushal, S. S.; Belt, K. T.; Stack, W. P.; Pouyat, R. V.; Groffman, P. M.; F, S. E.

    2006-05-01

    Urbanization has led to increased concentrations of metals such as lead (Pb), zinc (Zn), and copper (Cu) in streams due to industrial sources, domestic activities, vehicle use, and runoff from roadways. These metals can be dangerous to aquatic organisms and humans at high concentrations. We investigated variations in concentrations of heavy metals in streams across Baltimore, Maryland and within the context of convergent increases in salinity and organic carbon (two important variables that are known to affect metal transport in surface waters) due to urbanization. Despite past reductions of lead in gasoline and paints, mean concentrations of lead in some Baltimore streams were still approximately 75 micrograms/L and exceeded the U.S. EPA recommended criteria by 50 times. Mean concentrations of zinc and copper across Baltimore streams were also elevated and ranged between 15 to 140 micrograms/L and 2 to 40 micrograms/L, and mean concentrations of these metals were considerably higher than national means reported by the National Storm Water Quality database (NSWQ), which spans 3,770 storm events across the U.S. There were substantial increases in concentrations of heavy metals in streams during storms with greater than 80 percent, 70 percent, and 20 percent of storm samples exceeding recommended U.S. EPA metals criteria for Cu, Pb, and Zn respectively. Relationships between metal concentrations and stream discharge followed different patterns than nitrate and total phosphorus, other regulated pollutants in the Chesapeake Bay watershed, suggesting differences in sources and transport mechanisms within watersheds. Environmental factors such as increasing salinity from deicer use (with chloride concentrations in streams now ranging up to 5 g/L) may contribute to elevated transport of metals through ion exchange and mobilization of metals in soils and sediments. Environmental factors such as increasing organic carbon in urban streams, with ranges of 2 - 16 times greater

  14. Assessment of acid leachable trace metals in sediment cores from River Uppanar, Cuddalore, Southeast coast of India.

    PubMed

    Ayyamperumal, T; Jonathan, M P; Srinivasalu, S; Armstrong-Altrin, J S; Ram-Mohan, V

    2006-09-01

    An acid leachable technique is employed in core samples (C1, C2 and C3) to develop a baseline data on the sediment quality for trace metals of River Uppanar, Cuddalore, southeast coast of India. Acid leachable metals (Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn and Cd) indicate peak values at the sulphidic phase and enrichment of metals in the surface layers are due to the anthropogenic activities. Association of trace metals with Fe, Mn indicates their adsorption onto Fe-Mn oxyhydroxides and their correlation with S indicate that they are precipitated as metal sulphides. Factor analysis identified three possible types of geochemical associations and the supremacy of trace metals along with Fe, Mn, S and mud supports their geochemical associations. Factor analysis also signifies that anthropogenic activities have affected both the estuarine and fresh water regions of River Uppanar.

  15. Study on the factors affecting the quality of public bus transportation service in Bali Province using factor analysis

    NASA Astrophysics Data System (ADS)

    Susilawati, M.; Nilakusmawati, D. P. E.

    2017-06-01

    The volume of mobility flows are increasing day by day and the condition of the number of people using private transport modes contribute to traffic congestion. With the limited capacity of the road, one of the alternatives solution to reduce congestion is to optimize the use of public transport. The purposes of this study are to determine the factors that influence user’s satisfaction on the quality of public bus transportation service and determine variables that became identifier on the dominant factor affecting user’s satisfaction. The study was conducted for the public bus transportation between districts in the province of Bali, which is among the eight regencies and one municipality, using a questionnaire as a data collection instrument. Service variables determinant of user’s satisfaction in this study, described in 25 questions, which were analyzed using factor analysis. The results showed there were six factors that explain the satisfaction of users of public transport in Bali, with a total diversity of data that can be parsed by 61.436%. These factors are: Safety and comfort, Responsiveness, Capacity, Tangible, Safety, Reliability. The dominant factor affecting public transport user satisfaction is the safety and comfort, with the most influential variable is feeling concerned about the personal safety of users when on the bus.

  16. A study of factors affecting the adoption of server virtualization technology

    NASA Astrophysics Data System (ADS)

    Lu, Hsin-Ke; Lin, Peng-Chun; Chiang, Chang-Heng; Cho, Chien-An

    2018-04-01

    It has become a trend that worldwide enterprises and organizations apply new technologies to improve their operations; besides, it has higher cost and less flexibility to construct and manage traditional servers, therefore the current mainstream is to use server virtualization technology. However, from these new technology organizations will not necessarily get the expected benefits because each one has its own level of organizational complexity and abilities to accept changes. The researcher investigated key factors affecting the adoption of virtualization technology through two phases. In phase I, the researcher reviewed literature and then applied the dimensions of "Information Systems Success Model" (ISSM) to generalize the factors affecting the adoption of virtualization technology to be the preliminary theoretical framework and develop a questionnaire; in phase II, a three-round Delphi Method was used to integrate the opinions of experts from related fields which were then gradually converged in order to obtain a stable and objective questionnaire of key factors so that these results were expected to provide references for organizations' adoption of server virtualization technology and future studies.

  17. Factors Affecting Environmental Knowledge and Attitudes among Lebanese College Students

    ERIC Educational Resources Information Center

    Oweini, Ahmad; Houri, Ahmad

    2006-01-01

    This exploratory study aimed at assessing the variables that would positively affect the knowledge and attitude of a group of Lebanese college students regarding the environment, namely such factors as gender, age, previous hiking experience and living abroad. A purposeful sample of students attending the Lebanese American University, was asked to…

  18. Factors Affecting Performance of Undergraduate Students in Construction Related Disciplines

    ERIC Educational Resources Information Center

    Olatunji, Samuel Olusola; Aghimien, Douglas Omoregie; Oke, Ayodeji Emmanuel; Olushola, Emmanuel

    2016-01-01

    Academic performance of students in Nigerian institutions has been of much concern to all and sundry hence the need to assess the factors affecting performance of undergraduate students in construction related discipline in Nigeria. A survey design was employed with questionnaires administered on students in the department of Quantity Surveying,…

  19. Diurnal and seasonal trends and source apportionment of redox-active metals in Los Angeles using a novel online metal monitor and Positive Matrix Factorization (PMF)

    NASA Astrophysics Data System (ADS)

    Mousavi, Amirhosein; Sowlat, Mohammad H.; Sioutas, Constantinos

    2018-02-01

    In the present study, we identified the sources of four redox-active metals, including Iron (Fe), Chromium (Cr), Cupper (Cu), and Manganese (Mn) and quantified the contribution of these sources to PM2.5 concentrations in central Los Angeles, California, by employing time-resolved measurements (i.e., a time resolution of 2 h) with a recently developed online metal monitor and Positive Matrix Factorization (PMF). Size distribution of ambient PM (14 nm-10 μm) was measured using the Scanning Mobility Particle Sizer (SMPS) and Optical Particle Sizer (OPS). Auxiliary variables were also collected, including elemental (EC) and organic carbon (OC), gaseous pollutants (NO2 and O3), meteorological parameters (including relative humidity (RH) and temperature), and traffic data (for heavy- (HDVs) and light-duty vehicles (LDVs)). A 4-factor solution was found to be optimum for the chemically-speciated dataset, whereas a 5-factor solution appeared to be most plausible for the size distribution data. The factors included fresh traffic, soil/road dust, urban background aerosol, secondary aerosol, and nucleation (only resolved for the size distribution data). Fresh traffic was the major contributor to Fe and Cu concentrations, whereas Cr was mostly found in the urban background aerosol (reflecting a mixture of small local sources as well as aged traffic emissions), and Mn mostly came from both soil/road dust and was to a lesser degree found in urban background aerosol. Secondary aerosol did not contribute to the concentrations of any of these metals, but was associated with very high loading of OC, as expected. Even though the urban background aerosol and secondary aerosol appeared to be characterized by "aged" particles and have a rather homogeneous spatial distribution, the reactions and processes involved in their formation are entirely different. Our results provide insights into the sources of redox-active metals in central Los Angeles. They also underscore the benefits of

  20. Noneconomic factors influencing scrap metal disposition decisions at DOE and NRC-licensed nuclear facilities

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ewen, M.D.; Robinson, L.A.

    1997-02-01

    The U.S. Environmental Protection Agency (EPA) is currently developing radiation protection standards for scrap metal, which will establish criteria for the unconditional clearance of scrap from nuclear facilities. In support of this effort, Industrial Economics, Incorporated is assessing the costs and benefits attributable to the rulemaking. The first step in this analysis is to develop an in-depth understanding of the factors influencing scrap disposition decisions, so that one can predict current and future practices under existing requirements and compare them to the potential effects of EPA`s rulemaking. These baseline practices are difficult to predict due to a variety of factors.more » First, because decommissioning activities are just beginning at many sites, current practices do not necessarily provide an accurate indicator of how these practices may evolve as site managers gain experience with related decisions. Second, a number of different regulations and policies apply to these decisions, and the interactive effects of these requirements can be difficult to predict. Third, factors other than regulatory constraints and costs may have a significant effect on related decisions, such as concerns about public perceptions. In general, research suggests that these factors tend to discourage the unconditional clearance of scrap metal.« less

  1. Factors affecting the implementation of childhood vaccination communication strategies in Nigeria: a qualitative study.

    PubMed

    Oku, Afiong; Oyo-Ita, Angela; Glenton, Claire; Fretheim, Atle; Eteng, Glory; Ames, Heather; Muloliwa, Artur; Kaufman, Jessica; Hill, Sophie; Cliff, Julie; Cartier, Yuri; Bosch-Capblanch, Xavier; Rada, Gabriel; Lewin, Simon

    2017-02-15

    The role of health communication in vaccination programmes cannot be overemphasized: it has contributed significantly to creating and sustaining demand for vaccination services and improving vaccination coverage. In Nigeria, numerous communication approaches have been deployed but these interventions are not without challenges. We therefore aimed to explore factors affecting the delivery of vaccination communication in Nigeria. We used a qualitative approach and conducted the study in two states: Bauchi and Cross River States in northern and southern Nigeria respectively. We identified factors affecting the implementation of communication interventions through interviews with relevant stakeholders involved in vaccination communication in the health services. We also reviewed relevant documents. Data generated were transcribed verbatim and analysed using thematic analysis. We used the SURE framework to organise the identified factors (barriers and facilitators) affecting vaccination communication delivery. We then grouped these into health systems and community level factors. Some of the commonly reported health system barriers amongst stakeholders interviewed included: funding constraints, human resource factors (health worker shortages, training deficiencies, poor attitude of health workers and vaccination teams), inadequate infrastructure and equipment and weak political will. Community level factors included the attitudes of community stakeholders and of parents and caregivers. We also identified factors that appeared to facilitate communication activities. These included political support, engagement of traditional and religious institutions and the use of organised communication committees. Communication activities are a crucial element of immunization programmes. It is therefore important for policy makers and programme managers to understand the barriers and facilitators affecting the delivery of vaccination communication so as to be able to implement

  2. Factors affecting early and long-term outcomes after completion pneumonectomy.

    PubMed

    Chataigner, Olivier; Fadel, Elie; Yildizeli, Bedrettin; Achir, Abdallah; Mussot, Sacha; Fabre, Dominique; Mercier, Olaf; Dartevelle, Philippe G

    2008-05-01

    To identify factors that affect operative mortality and morbidity and long-term survival after completion pneumonectomy. We retrospectively reviewed the charts of consecutive patients who underwent completion pneumonectomy at our cardiothoracic surgery department from January 1996 to December 2005. We identified 69 patients, who accounted for 17.8% of all pneumonectomies during the study period; 22 had benign disease and 47 malignant disease (second primary lung cancer, n=19; local recurrence, n=17; or metastasis, n=11). There were 50 males and 19 females with a mean age of 60 years (range, 29-80 years). Postoperative mortality was 12% and postoperative morbidity 41%. Factors associated with postoperative mortality included obesity (p=0.005), coronary artery disease (p=0.03), removal of the right lung (p=0.02), advanced age (p=0.02), and renal failure (p<0.0001). Preoperative renal failure was the only significant risk factor for mortality by multivariate analysis (p=0.036). Bronchopleural fistula developed in seven patients (10%), with risk factors being removal of the right lung (p=0.04) and mechanical stump closure (p=0.03). Overall survival was 65% after 3 years and 46% after 5 years. Long-term survival was not affected by the reason for completion pneumonectomy. Although long-term survival was acceptable, postoperative mortality and morbidity rates remained high, confirming the reputation of completion pneumonectomy as a challenging procedure. Significant comorbidities and removal of the right lung were the main risk factors for postoperative mortality. Improved patient selection and better management of preoperative renal failure may improve the postoperative outcomes of this procedure, which offers a chance for prolonged survival.

  3. Bioaccumulation of Heavy Metals in Some Tissues of Fish in Lake Geriyo, Adamawa State, Nigeria.

    PubMed

    Bawuro, A A; Voegborlo, R B; Adimado, A A

    2018-01-01

    Bioaccumulation of heavy metals (Zn, Pb, Cd, and Cu) was determined in the liver, gills, and flesh from benthic and pelagic fish species collected from Lake Geriyo covering two seasons. The levels of the heavy metals varied significantly among fish species and organs. Flesh possessed the lowest concentration of all the metals. Liver was the target organ for Zn, Cu, and Pb accumulations. Cd however exhibited higher concentration in the gills. Fish species showed interspecific variation of metals. These differences were discussed for the contribution of potential factors that affected metals uptake like age, geographical distribution, and species-specific factors. The concentration of metals in fish flesh was accepted by the international legislation limits for Cu, Zn, and Cd; however, Pb transcend in Clarias and Tilapia during wet season and Heterotis in both seasons, hence unsafe for human consumption and a threat to public health. These levels might be due to anthropogenic inputs as there is no industrial activity around the lake.

  4. Decomposition Mechanism and Decomposition Promoting Factors of Waste Hard Metal for Zinc Decomposition Process (ZDP)

    NASA Astrophysics Data System (ADS)

    Pee, J. H.; Kim, Y. J.; Kim, J. Y.; Seong, N. E.; Cho, W. S.; Kim, K. J.

    2011-10-01

    Decomposition promoting factors and decomposition mechanism in the zinc decomposition process of waste hard metals which are composed mostly of tungsten carbide and cobalt were evaluated. Zinc volatility amount was suppressed and zinc steam pressure was produced in the reaction graphite crucible inside an electric furnace for ZDP. Reaction was done for 2 hrs at 650 °C, which 100 % decomposed the waste hard metals that were over 30 mm thick. As for the separation-decomposition of waste hard metals, zinc melted alloy formed a liquid composed of a mixture of γ-β1 phase from the cobalt binder layer (reaction interface). The volume of reacted zone was expanded and the waste hard metal layer was decomposed-separated horizontally from the hard metal. Zinc used in the ZDP process was almost completely removed-collected by decantation and volatilization-collection process at 1000 °C. The small amount of zinc remaining in the tungsten carbide-cobalt powder which was completely decomposed was fully removed by using phosphate solution which had a slow cobalt dissolution speed.

  5. Factors Affecting 25-Hydroxyvitamin D Concentration in Response to Vitamin D Supplementation

    PubMed Central

    Mazahery, Hajar; von Hurst, Pamela R.

    2015-01-01

    Sun exposure is the main source of vitamin D. Due to many lifestyle risk factors vitamin D deficiency/insufficiency is becoming a worldwide health problem. Low 25(OH)D concentration is associated with adverse musculoskeletal and non-musculoskeletal health outcomes. Vitamin D supplementation is currently the best approach to treat deficiency and to maintain adequacy. In response to a given dose of vitamin D, the effect on 25(OH)D concentration differs between individuals, and it is imperative that factors affecting this response be identified. For this review, a comprehensive literature search was conducted to identify those factors and to explore their significance in relation to circulating 25(OH)D response to vitamin D supplementation. The effect of several demographic/biological factors such as baseline 25(OH)D, aging, body mass index(BMI)/body fat percentage, ethnicity, calcium intake, genetics, oestrogen use, dietary fat content and composition, and some diseases and medications has been addressed. Furthermore, strategies employed by researchers or health care providers (type, dose and duration of vitamin D supplementation) and environment (season) are other contributing factors. With the exception of baseline 25(OH)D, BMI/body fat percentage, dose and type of vitamin D, the relative importance of other factors and the mechanisms by which these factors may affect the response remains to be determined. PMID:26121531

  6. Factors Affecting Aerosol Radiative Forcing

    NASA Astrophysics Data System (ADS)

    Wang, Jingxu; Lin, Jintai; Ni, Ruijing

    2016-04-01

    Rapid industrial and economic growth has meant a large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RF of aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissions per unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size. South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions, its aerosol RF is alleviated by its lowest chemical efficiency. The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is lowered by a small per capita GDP. Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The

  7. Factors Affecting Aerosol Radiative Forcing

    NASA Astrophysics Data System (ADS)

    Wang, J.; Lin, J.; Ni, R.

    2016-12-01

    Rapid industrial and economic growth has meant large amount of aerosols in the atmosphere with strong radiative forcing (RF) upon the climate system. Over parts of the globe, the negative forcing of aerosols has overcompensated for the positive forcing of greenhouse gases. Aerosol RF is determined by emissions and various chemical-transport-radiative processes in the atmosphere, a multi-factor problem whose individual contributors have not been well quantified. In this study, we analyze the major factors affecting RF of secondary inorganic aerosols (SIOAs, including sulfate, nitrate and ammonium), primary organic aerosol (POA), and black carbon (BC). We analyze the RFof aerosols produced by 11 major regions across the globe, including but not limited to East Asia, Southeast Asia, South Asia, North America, and Western Europe. Factors analyzed include population size, per capita gross domestic production (GDP), emission intensity (i.e., emissionsper unit GDP), chemical efficiency (i.e., mass per unit emissions) and radiative efficiency (i.e., RF per unit mass). We find that among the 11 regions, East Asia produces the largest emissions and aerosol RF, due to relatively high emission intensity and a tremendous population size.South Asia produce the second largest RF of SIOA and BC and the highest RF of POA, in part due to its highest chemical efficiency among all regions. Although Southeast Asia also has large emissions,its aerosol RF is alleviated by its lowest chemical efficiency.The chemical efficiency and radiative efficiency of BC produced by the Middle East-North Africa are the highest across the regions, whereas its RF is loweredbyasmall per capita GDP.Both North America and Western Europe have low emission intensity, compensating for the effects on RF of large population sizes and per capita GDP. There has been a momentum to transfer industries to Southeast Asia and South Asia, and such transition is expected to continue in the coming years. The resulting

  8. Mothers recovering from cocaine addiction: factors affecting parenting skills.

    PubMed

    Coyer, S M

    2001-01-01

    To identify factors that may influence parenting by mothers who are recovering from cocaine addiction. Exploratory descriptive, with in-depth unstructured interviews. Interviews were conducted in the woman's home or in a treatment center. A convenience sample of 11 women recovering from cocaine addiction who were mothers of children 3 years of age and younger. A content analysis was used to analyze the interview data. Two themes, personal/psychologic factors and environmental/contextual factors, and four subthemes emerged. They identify issues that may affect parenting by mothers being treated for cocaine addiction. Subthemes included low self-esteem, difficulty developing a maternal identity, isolation from friends and family, and chronic life stress. This study provides a better understanding of the sources contributing to vulnerability in the parenting role for mothers recovering from cocaine addiction and will assist nurses in providing care for these mothers and their children.

  9. Assessment of heavy metal pollution risks in Yonki Reservoir environmental matrices affected by gold mining activity.

    PubMed

    Kapia, Samuel; Rao, B K Rajashekhar; Sakulas, Harry

    2016-10-01

    This study reports the heavy metal (Hg, Cd, Cr, Cu, and Pb) contamination risks to and safety of two species of fresh water fish (tilapia, Oreochromis mossambicus and carp, Cyprinus carpio) that are farmed in the Yonki Reservoir in the Eastern Highlands of Papua New Guinea (PNG). The upper reaches of the reservoir are affected by alluvial and large-scale gold mining activities. We also assessed heavy metal levels in the surface waters and sediments and in selected aquatic plant species from the reservoir and streams that intersect the gold mining areas. The water quality was acceptable, except for the Cr concentration, which exceeded the World Health Organization (WHO) standard for water contamination. The sediments were contaminated with Cd and Cu in most of the sampling stations along the upstream waters and the reservoir. The Cd concentration in the sediments exceeded the US Environmental Protection Agency's Sediment Quality Guideline (SQG) values, and the geoaccumulation index (Igeo) values indicated heavy to extreme pollution. In addition, the Cd, Cu, and Pb concentrations in aquatic plants exceeded the WHO guidelines for these contaminants. Between the fish species, tilapia accumulated significantly higher (P < 0.05) Cu in their organ tissues than carp, confirming the bioaccumulation of some metals in the aquatic fauna. The edible muscles of the fish specimens had metal concentrations below the maximum permissible levels established by statutory guidelines. In addition, a human health risk assessment, performed using the estimated weekly intake (EWI) values, indicated that farmed fish from the Yonki Reservoir are safe for human consumption.

  10. Factors Affecting the Interest of Israeli Social Work Students in Working with Different Client Groups

    ERIC Educational Resources Information Center

    Krumer-Nevo, Michal; Weiss, Idit

    2006-01-01

    Employing a large-scale sample of 521 BSW students from 4 Israeli schools of social work, this research examines the factors affecting social work students' interest in working with a wide range of client groups. The results suggest that student interest in working with specific client groups is affected by factors related to desire for…

  11. Understanding processes affecting mineral deposits in humid environments

    USGS Publications Warehouse

    Seal, Robert R.; Ayuso, Robert A.

    2011-01-01

    Recent interdisciplinary studies by the U.S. Geological Survey have resulted in substantial progress toward understanding the influence that climate and hydrology have on the geochemical signatures of mineral deposits and the resulting mine wastes in the eastern United States. Specific areas of focus include the release, transport, and fate of acid, metals, and associated elements from inactive mines in temperate coastal areas and of metals from unmined mineral deposits in tropical to subtropical areas; the influence of climate, geology, and hydrology on remediation options for abandoned mines; and the application of radiogenic isotopes to uniquely apportion source contributions that distinguish natural from mining sources and extent of metal transport. The environmental effects of abandoned mines and unmined mineral deposits result from a complex interaction of a variety of chemical and physical factors. These include the geology of the mineral deposit, the hydrologic setting of the mineral deposit and associated mine wastes, the chemistry of waters interacting with the deposit and associated waste material, the engineering of a mine as it relates to the reactivity of mine wastes, and climate, which affects such factors as temperature and the amounts of precipitation and evapotranspiration; these factors, in turn, influence the environmental behavior of mineral deposits. The role of climate is becoming increasingly important in environmental investigations of mineral deposits because of the growing concerns about climate change.

  12. Factors Affecting English Language Teaching and Learning in Higher Education

    ERIC Educational Resources Information Center

    Nguyen, Hong Thi; Warren, Wendy; Fehring, Heather

    2014-01-01

    This paper reports part of a study that aims to explore factors affecting the efficacy of non-major English teaching and learning in Vietnamese higher education through an investigation of classroom practices. Eight non-participant class observations were conducted at HUTECH University, Ho Chi Minh City, Vietnam. The study's findings show that…

  13. The Impact of CLIL on Affective Factors and Vocabulary Learning

    ERIC Educational Resources Information Center

    Heras, Arantxa; Lasagabaster, David

    2015-01-01

    The aim of this article is twofold: to assess the effectiveness of a CLIL (content and language integrated learning) module on affective factors (motivation and self-esteem), and to test the purported blurring effect of CLIL on gender differences in foreign language learning. Forty-six students in their fourth year of compulsory secondary…

  14. The Perspective of Gozitan Teachers on Factors Affecting Students' Achievement

    ERIC Educational Resources Information Center

    Xuereb, Lorna; De Giovanni, Katya Sarah

    2016-01-01

    This study aims at exploring the impact of factors at pupil, teacher and school levels on students? academic achievement. Moreover, the main purpose was that of investigating which one of the three levels is most likely to affect students? educational accomplishment. A questionnaire was administered to 100 Gozitan teachers. Results were analysed…

  15. Smoking status and occupational exposure affects oxidative DNA injury in boilermakers exposed to metal fume and residual oil fly ash.

    PubMed

    Mukherjee, Sutapa; Palmer, Lyle J; Kim, Jee Young; Aeschliman, David B; Houk, Robert S; Woodin, Mark A; Christiani, David C

    2004-03-01

    Epidemiologic studies demonstrate increased cancer incidence among workers exposed to polycyclic aromatic hydrocarbons (PAH) and metals, probably through cumulative oxidative DNA damage in response to carcinogens. Boilermakers are exposed to particulates of residual oil fly ash (ROFA) and metal fume that contain carcinogenic PAH and metals. We conducted a repeated-measures cohort study in boilermakers during the overhaul of an oil-fired boiler to determine a possible association between the level of 8-hydroxy-2'-deoxyguanosine (8-OH-dG; an oxidative injury biomarker) and biomarkers of PAH (1-hydroxypyrene; 1-OHP) and metal exposure. Preshift and postshift urine samples were analyzed for 8-OH-dG, cotinine, 1-OHP, and metals. Generalized estimating equations were used to model the multivariate relationship of 8-OH-dG to the explanatory variables of interest. Biomarker levels were determined for 181 urine samples from 20 male subjects (mean age 45 years, 50% smokers). Metal and 1-OHP levels increased cross-week and were affected by smoking status. Levels of 8-OH-dG were higher in nonsmokers at the start of the workweek yet declined after occupational exposure to similar levels as in smokers. Multivariate analysis indicated that metal x cotinine interaction terms for nickel, vanadium, chromium, and copper were significantly associated with the 8-OH-dG level, but there were differential effects depending on the metal. This study suggests that oxidative DNA damage in boilermakers is influenced by the interaction between occupational exposures and smoking status. In addition, boilermakers may have reduced ability to repair damaged DNA after ROFA and metal fume exposure. This finding has clinical relevance because these exposures may increase the cancer susceptibility of boilermakers.

  16. 77 FR 18862 - Brazil: Competitive Factors Affecting U.S. and Brazilian Agricultural Sales in Selected Third...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 332-524] Brazil: Competitive Factors Affecting U.S. and Brazilian Agricultural Sales in Selected Third Country Markets AGENCY: United States... Committee in investigation No. 332-524, Brazil: Competitive Factors In Brazil Affecting U.S. and Brazilian...

  17. TRANSCRIPTION FACTOR ACTIVATION FOLLOWING EXPOSURE OF AN INTACT LUNG PREPARATION TO METALLIC PARTICULATE MATTER

    EPA Science Inventory

    TRANSCRIPTION FACTOR ACTIVATION FOLLOWING EXPOSURE OF AN INTACT LUNG PREPARATION TO METALLIC PARTICULATE MATTER

    James M. Samet1,2, Robert Silbajoris1, Tony Huang1 and Ilona Jaspers3

    1Human Studies Division, National Health and Environmental Effects Research Laborato...

  18. Factors affecting the stability of reverse shoulder arthroplasty: a biomechanical study.

    PubMed

    Clouthier, Allison L; Hetzler, Markus A; Fedorak, Graham; Bryant, J Tim; Deluzio, Kevin J; Bicknell, Ryan T

    2013-04-01

    Despite the success of reverse shoulder arthroplasty (RSA) in treating patients with painful pseudoparalytic shoulders, instability is a common complication and currently the factors affecting stability are not well understood. The objective of this study was to investigate a number of factors as well as the interactions between factors to determine how they affect the stability of the prosthesis. These factors included: active arm posture (abduction and abduction plane angles), loading direction, glenosphere diameter and eccentricity, and humeral socket constraint. Force required to dislocate the joint, determined using a biomechanical shoulder simulator, was used as a measure of stability. A factorial design experiment was implemented to examine the factors and interactions. Actively increasing the abduction angle by 15° leads to a 30% increase in stability and use of an inferior-offset rather than a centered glenosphere improved stability by 17%. Use of a more constrained humeral socket also increased stability; but the effect was dependent on loading direction, with a 88% improvement for superior loading, 66% for posterior, 36% for anterior, and no change for inferior loading. Abduction plane angle and glenosphere diameter had no effect on stability. Increased glenohumeral abduction and the use of an inferior-offset glenosphere were found to increase the stability of RSA. Additionally, use of a more constrained humeral socket increased stability for anterior, posterior, and superior loading. These identified factor effects have the potential to decrease the risk of dislocation following RSA. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

  19. Factors affecting the palpability of breast lesion by self-examination.

    PubMed

    Lam, W W M; Chan, C P; Chan, C F; Mak, C C C; Chan, C F; Chong, K W H; Leung, M H J; Tang, M H

    2008-03-01

    This study aims to assess the accuracy of detection of breast lesion by breast self-examination and to assess different factors affecting the accuracy. All consecutive Chinese female patients, who attended our breast imaging unit in 2001, completed our questionnaire, had retrievable hard copy films, and had more than three years clinical follow-up, were recruited for this study. Different factors, such as age, menopausal status, previous experience of breastfeeding, family history of breast cancer, previous history of mastectomy or lumpectomy, hormonal therapy, oral contraceptive pills and previous history of mammography, were correlated with accuracy in self-detection of breast lesions retrospectively. The nature, size and location of the lesion, and breast size based on imaging, were also correlated with the accuracy in self-detection of breast lesions. A total of 163 questionnaires were analysed. 111 patients detected a breast lesion themselves and 24 of these lesions were false-positives. A total of 173 lesions (27 cancerous, 146 benign lesions) were documented by either ultrasonography and/or mammography, and confirmed by either histology or three-year clinical follow-up. The overall sensitivity in detecting both benign and malignant breast lesions was 71% when number of breast lesions was used as the denominator, and up to 78% sensitivity was achieved when number of patients was used as the denominator. History of mastectomy, and size and nature of the lesions were found to affect the accuracy of self-detection of breast lesions. Overall, breast self-examinations were effective in the detection of breast lesions and factors such as size of lesion, nature of the lesion and history of mastectomy affect the accuracy of the detections. Breast self-examination should be promoted for early detection of breast cancer.

  20. Factors Affecting the Effectiveness and Use of Moodle: Students' Perception

    ERIC Educational Resources Information Center

    Damnjanovic, Vesna; Jednak, Sandra; Mijatovic, Ivana

    2015-01-01

    The purpose of this research paper is to identify the factors affecting the effectiveness of Moodle from the students' perspective. The research hypotheses derived from the suggested extended Seddon model have been empirically validated using the responses to a survey on e-learning usage among 255 users. We tested the model across higher education…

  1. New Perspectives on Oxidized Genome Damage and Repair Inhibition by Pro-Oxidant Metals in Neurological Diseases

    PubMed Central

    Mitra, Joy; Guerrero, Erika N.; Hegde, Pavana M.; Wang, Haibo; Boldogh, Istvan; Rao, Kosagi Sharaf; Mitra, Sankar; Hegde, Muralidhar L.

    2014-01-01

    The primary cause(s) of neuronal death in most cases of neurodegenerative diseases, including Alzheimer’s and Parkinson’s disease, are still unknown. However, the association of certain etiological factors, e.g., oxidative stress, protein misfolding/aggregation, redox metal accumulation and various types of damage to the genome, to pathological changes in the affected brain region(s) have been consistently observed. While redox metal toxicity received major attention in the last decade, its potential as a therapeutic target is still at a cross-roads, mostly because of the lack of mechanistic understanding of metal dyshomeostasis in affected neurons. Furthermore, previous studies have established the role of metals in causing genome damage, both directly and via the generation of reactive oxygen species (ROS), but little was known about their impact on genome repair. Our recent studies demonstrated that excess levels of iron and copper observed in neurodegenerative disease-affected brain neurons could not only induce genome damage in neurons, but also affect their repair by oxidatively inhibiting NEIL DNA glycosylases, which initiate the repair of oxidized DNA bases. The inhibitory effect was reversed by a combination of metal chelators and reducing agents, which underscore the need for elucidating the molecular basis for the neuronal toxicity of metals in order to develop effective therapeutic approaches. In this review, we have focused on the oxidative genome damage repair pathway as a potential target for reducing pro-oxidant metal toxicity in neurological diseases. PMID:25036887

  2. Factors Affecting Conservation Practice Behavior of CRP Participants in Alabama

    Treesearch

    Okwudili Onianwa; Gerald Wheelock; Shannon Hendrix

    1999-01-01

    This study examines the factors that affect conservation practice choices of CRP farmers in Alabama. From over 9,000 contracts enrolled in the state between 1986 and 1995, 594 were randomly selected for the study. A multiple-regression analysis was employed to analyze the data. Results indicate that education, ratio ofcropland in CRP, farm size, gender, prior crop...

  3. Factors Affecting the Retention Decisions of Female Surface Warfare Officers

    DTIC Science & Technology

    2003-03-01

    NAVAL POSTGRADUATE SCHOOL Monterey, California THESIS Approved for public release; distribution is unlimited. FACTORS AFFECTING THE RETENTION...Warfare Officers 6. AUTHOR(S) Clifton, Elizabeth A. 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School ...for the degree of MASTER OF SCIENCE IN LEADERSHIP AND HUMAN RESOURCE DEVELOPMENT from the NAVAL POSTGRADUATE SCHOOL March 2003

  4. Do weirs affect the physical and geochemical mobility of toxic metals in mining-impacted floodplain sediments?

    NASA Astrophysics Data System (ADS)

    Bulcock, Amelia; Coleman, Alexandra; Whitfield, Elizabeth; Andres Lopez-Tarazon, Jose; Byrne, Patrick; Whitfield, Greg

    2015-04-01

    Weirs are common river structures designed to modify river channel hydraulics and hydrology for purposes of navigation, flood defence, irrigation and hydrometry. By design, weirs constrain natural flow processes and affect sediment flux and river channel forms leading to homogenous river habitats and reduced biodiversity. The recent movement towards catchment-wide river restoration, driven by the EU Water Framework Directive, has recognised weirs as a barrier to good ecological status. However, the removal of weirs to achieve more 'natural' river channels and flow processes is inevitably followed by a period of adjustment to the new flow regime and sediment flux. This period of adjustment can have knock-on effects that may increase flood risk, sedimentation and erosion until the river reaches a state of geomorphological equilibrium. Many catchments in the UK contain a legacy of toxic metals in floodplain sediments due to historic metal mining activities. The consequences of weir removal in these catchments may be to introduce 'stored' mine wastes into the river system with severe implications for water quality and biodiversity. The purpose of this study is to investigate the potential impact of a weir on the physical and geochemical mobilisation of mine wastes in the formerly mined River Twymyn catchment, Wales. Our initial investigations have shown floodplain and riverbed sediments to be grossly contaminated (up to 15,500 mg/kg Pb) compared to soil from a pre-mining Holocene terrace (180 mg/kg Pb). Geomorphological investigations also suggest that weir removal will re-establish more dynamic river channel processes resulting in lateral migration of the channel and erosion of contaminated floodplain sediments. These data will be used as a baseline for more detailed investigations of the potential impact of weirs on the physical and geochemical mobilisation of contaminated sediments. We have two specific objectives. (1) Geomorphological assessments will use unmanned

  5. Feasibility analysis of EDXRF method to detect heavy metal pollution in ecological environment

    NASA Astrophysics Data System (ADS)

    Hao, Zhixu; Qin, Xulei

    2018-02-01

    The change of heavy metal content in water environment, soil and plant can reflect the change of heavy metal pollution in ecological environment, and it is important to monitor the trend of heavy metal pollution in eco-environment by using water environment, soil and heavy metal content in plant. However, the content of heavy metals in nature is very low, the background elements of water environment, soil and plant samples are complex, and there are many interfering factors in the EDXRF system that will affect the spectral analysis results and reduce the detection accuracy. Through the contrastive analysis of several heavy metal elements detection methods, it is concluded that the EDXRF method is superior to other chemical methods in testing accuracy and method feasibility when the heavy metal pollution in soil is tested in ecological environment.

  6. Factors Affecting Lactoferrin Concentration in Human Milk: How Much Do We Know?

    PubMed Central

    Villavicencio, Aasith; Rueda, Maria S.; Turin, Christie G.; Ochoa, Theresa J.

    2017-01-01

    Lactoferrin (LF) is a breast milk glycoprotein with antimicrobial and anti-inflammatory effects. Its beneficial properties in infants, especially in those born preterm, are currently being studied in clinical trials. However, the maternal and nursing infant factors that may affect the concentration of LF in breast milk are still not clear. We conducted a systematic review to investigate the factors that may affect LF concentration. We used a 2-step approach to identify the eligible studies according to inclusion/exclusion criteria and to determine which studies would be considered. We included 70 qualified articles from 29 countries with publication dates ranging from 1976 to 2015. We described the correlation between LF concentration in breast milk and lactation stage; 10 maternal factors, such as race, parity, among others; and 2 infant factors, infections and prematurity. Colostrum has the highest LF levels, but they decrease with days postpartum. No other factor has been consistently associated with LF concentration. A major limitation of the majority of the published studies is the small sample size and the different methods used to measure LF concentration. Therefore, there is a need for large, multicenter studies with standardized study design, sample collection, and LF measurement methods to identify clinically significant factors associated with LF expression in breast milk, which will help promote exclusive breastfeeding in preterm infants. PMID:28075610

  7. Current status of trace metal pollution in soils affected by industrial activities.

    PubMed

    Kabir, Ehsanul; Ray, Sharmila; Kim, Ki-Hyun; Yoon, Hye-On; Jeon, Eui-Chan; Kim, Yoon Shin; Cho, Yong-Sung; Yun, Seong-Taek; Brown, Richard J C

    2012-01-01

    There is a growing public concern over the potential accumulation of heavy metals in soil, owing to rapid industrial development. In an effort to describe the status of the pollutions of soil by industrial activities, relevant data sets reported by many studies were surveyed and reviewed. The results of our analysis indicate that soils were polluted most significantly by metals such as lead, zinc, copper, and cadmium. If the dominant species are evaluated by the highest mean concentration observed for different industry types, the results were grouped into Pb, Zn, Ni, Cu, Fe, and As in smelting and metal production industries, Mn and Cd in the textile industry, and Cr in the leather industry. In most cases, metal levels in the studied areas were found to exceed the common regulation guideline levels enforced by many countries. The geoaccumulation index (I(geo)), calculated to estimate the enrichment of metal concentrations in soil, showed that the level of metal pollution in most surveyed areas is significant, especially for Pb and Cd. It is thus important to keep systematic and continuous monitoring of heavy metals and their derivatives to manage and suppress such pollution.

  8. Current Status of Trace Metal Pollution in Soils Affected by Industrial Activities

    PubMed Central

    Kabir, Ehsanul; Ray, Sharmila; Kim, Ki-Hyun; Yoon, Hye-On; Jeon, Eui-Chan; Kim, Yoon Shin; Cho, Yong-Sung; Yun, Seong-Taek; Brown, Richard J. C.

    2012-01-01

    There is a growing public concern over the potential accumulation of heavy metals in soil, owing to rapid industrial development. In an effort to describe the status of the pollutions of soil by industrial activities, relevant data sets reported by many studies were surveyed and reviewed. The results of our analysis indicate that soils were polluted most significantly by metals such as lead, zinc, copper, and cadmium. If the dominant species are evaluated by the highest mean concentration observed for different industry types, the results were grouped into Pb, Zn, Ni, Cu, Fe, and As in smelting and metal production industries, Mn and Cd in the textile industry, and Cr in the leather industry. In most cases, metal levels in the studied areas were found to exceed the common regulation guideline levels enforced by many countries. The geoaccumulation index (I geo), calculated to estimate the enrichment of metal concentrations in soil, showed that the level of metal pollution in most surveyed areas is significant, especially for Pb and Cd. It is thus important to keep systematic and continuous monitoring of heavy metals and their derivatives to manage and suppress such pollution. PMID:22645468

  9. Factors affecting assertiveness among student nurses.

    PubMed

    Ibrahim, Sanaa Abd El Azim

    2011-05-01

    This study aimed to investigate the factors affecting assertiveness among student nurses. The study was carried out at Faculty of Nursing, Port-Said University, on 207 student nurses from four different grades. Rathus Assertiveness Schedule, consisted of 30 items, was used to measure the students' assertiveness level and a 12-item scale developed by Spreitzer was used to measure students' psychological empowerment. The study results showed that 60.4% of the students were assertive, while about half of the students were empowered. A positive relation between student assertiveness and psychological empowerment was detected. Moreover, positive relations regarding family income and students' assertiveness and psychological empowerment were determined. The study recommended introduction of specific courses aiming at enhancing the acquisition of assertiveness skills, in addition, nurse educators must motivate their students to express their opinion and personal rights and also they must pay attention for students' empowerment and enhance students' autonomy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Factors Affecting Regional Per-Capita Carbon Emissions in China Based on an LMDI Factor Decomposition Model

    PubMed Central

    Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

    2013-01-01

    China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model–panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity. PMID:24353753

  11. Factors affecting regional per-capita carbon emissions in China based on an LMDI factor decomposition model.

    PubMed

    Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

    2013-01-01

    China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model-panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity.

  12. Friction, Wear, and Surface Damage of Metals as Affected by Solid Surface Films

    NASA Technical Reports Server (NTRS)

    Bisson, Edmond E; Johnson, Robert L; Swikert, Max A; Godfrey, Douglas

    1956-01-01

    As predicted by friction theory, experiments showed that friction and surface damage of metals can be reduced by solid surface films. The ability of materials to form surface films that prevent welding was a very important factor in wear of dry and boundary lubricated surfaces. Films of graphitic carbon on cast irons, nio on nickel alloys, and feo and fe sub 3 o sub 4 on ferrous materials were found to be beneficial. Abrasive films such as fe sub 2 o sub 3 or moo sub 3 were definitely detrimental. It appears that the importance of oxide films to friction and wear processes has not been fully appreciated.

  13. [Factors affecting infant mortality (author's transl)].

    PubMed

    Chackiel, J

    1982-04-01

    The purpose of this paper is to analyze the differentials and detect factors affecting infant mortality on the basis of data obtained from the fertility surveys from those countries participating in the World Fertility Survey. In particular, this includes the surveys carried out in Colombia, Peru, Costa Rica, Panama, and the Dominican Republic. 3 types of explanatory variables may be considered from the information available: 1) context variables related to the mother's environment; 2) socioeconomic variables based on the educational and economic characteristics of the mother and her last husband; and 3) biological factors (from each woman's pregnancy history) such as mother's age at birth of the child, order of birth, interbirth interval, etc. The countries, whether high or low mortality, present great differences in child mortality in most of the variables considered. In Panama and Costa Rica there are population sectors with infant mortality rates of around 100/1000 live births, whereas in Peru these are over 150/1000 (children from mothers without education, low agricultural strata, etc.). Besides presenting the differentials, a methodological test is made through the application to Costa Rica and Peru of the Proportional Hazards Model which permits analysis of the effects of variables when acting simultaneously upon mortality in early childhood. The variables which show the highest disparity in mortality level are: natural region among the context variables, education of mother among the socioeconomic variables, and interbirth interval and maternal age at birth of their children among the biological ones.

  14. Laboratory studies on the tribology of hard bearing hip prostheses: ceramic on ceramic and metal on metal.

    PubMed

    Vassiliou, K; Scholes, S C; Unsworth, A

    2007-01-01

    Total hip replacements offer relief to a great many patients every year around the world. With an expected service life of around 25 years on most devices, and with younger and younger patients undergoing this surgery, it is of great importance to understand the mechanisms of their function. Tribological testing of both conventional and hard bearing joint combinations have been conducted in many centres throughout the world, and, after being initially abandoned owing to premature failures, hard bearing combinations have been revisited as viable options for joint replacements. Improved design, manufacturing procedures, and material compositions have led to improved performance over first-generation designs in both metal-on-metal and ceramic-on-ceramic hip prostheses. This paper offers a review of the work conducted in an attempt to highlight the most important factors affecting joint performance and tribology of hard bearing combinations. The tribological performance of these joints is superior to that of conventional metal- or ceramic-on-polymer designs.

  15. Risk of antibiotic resistance from metal contaminated soils

    NASA Astrophysics Data System (ADS)

    Knapp, Charles

    2013-04-01

    It is known that contaminated soils can lead to increased incidence of illness and disease, but it may also prevent our ability to fight disease. Many antibiotic resistant genes (ARG) acquired by bacteria originate from the environment. It is important to understand factors that influence levels of ARG in the environment, which could affect us clinically and agriculturally. The presence of elevated metal content in soils often promotes antibiotic resistance in exposed microorganisms. Using qPCR, the abundances of ARG to compare levels with geochemical conditions in randomly selected soils from several countries. Many ARG positively correlated with soil metal content, especially copper, chromium, nickel, lead, and iron. Results suggest that geochemical metal conditions influence the potential for antibiotic resistance in soil, which might be used to estimate baseline gene presence on various landscape scales and may translate to epidemiological risk of antibiotic-resistance transmission from the environment. This suggests that we may have to reconsider tolerances of metal pollution in the environment.

  16. Factors affecting rotator cuff healing after arthroscopic repair: osteoporosis as one of the independent risk factors.

    PubMed

    Chung, Seok Won; Oh, Joo Han; Gong, Hyun Sik; Kim, Joon Yub; Kim, Sae Hoon

    2011-10-01

    The prognostic factors associated with structural outcome after arthroscopic rotator cuff repair have not yet been fully determined. The hypothesis of this study was that bone mineral density (BMD) is an important prognostic factor affecting rotator cuff healing after arthroscopic cuff repair. Cohort study; Level of evidence, 3. Among 408 patients who underwent arthroscopic repair for full-thickness rotator cuff tear between January 2004 and July 2008, 272 patients were included whose postoperative cuff integrity was verified by computed tomography arthrography (CTA) or ultrasonography (USG) and simultaneously who were evaluated by various functional outcome instruments. The mean age at the time of operation was 59.5 ± 7.9 years. Postoperative CTA or USG was performed at a mean 13.0 ± 5.1 months after surgery, and the mean follow-up period was 37.2 ± 10.0 months (range, 24-65 months). The clinical, structural, and surgery-related factors affecting cuff integrity including BMD were analyzed using both univariate and multivariate analysis. Evaluation of postoperative cuff integrity was performed by musculoskeletal radiologists who were unaware of the present study. The failure rate of rotator cuff healing was 22.8% (62 of 272). The failure rate was significantly higher in patients with lower BMD (P < .001); older age (P < .001); female gender (P = .03); larger tear size (P < .001); higher grade of fatty infiltration (FI) of the supraspinatus, infraspinatus, and subscapularis (all P < .001); diabetes mellitus (P = .02); shorter acromiohumeral distance (P < .001); and associated biceps procedure (P < .001). However, in the multivariate analysis, only BMD (P = .001), FI of the infraspinatus (P = .01), and the amount of retraction (P = .03) showed a significant relationship with cuff healing failure following arthroscopic rotator cuff repair. Bone mineral density, as well as FI of the infraspinatus and amount of retraction, was an independent determining factor

  17. Factors that affect the onset of action of non-depolarizing neuromuscular blocking agents

    PubMed Central

    Kim, Yong Byum; Sung, Tae-Yun

    2017-01-01

    Neuromuscular blockade plays an important role in the safe management of patient airways, surgical field improvement, and respiratory care. Rapid-sequence induction of anesthesia is indispensable to emergency surgery and obstetric anesthesia, and its purpose is to obtain a stable airway, adequate depth of anesthesia, and appropriate respiration within a short period of time without causing irritation or damage to the patient. There has been a continued search for new neuromuscular blocking drugs (NMBDs) with a rapid onset of action. Factors that affect the onset time include the potency of the NMBDs, the rate of NMBDs reaching the effect site, the onset time by dose control, metabolism and elimination of NMBDs, buffered diffusion to the effect site, nicotinic acetylcholine receptor subunit affinity, drugs that affect acetylcholine (ACh) production and release at the neuromuscular junction, drugs that inhibit plasma cholinesterase, presynaptic receptors responsible for ACh release at the neuromuscular junction, anesthetics or drugs that affect muscle contractility, site and methods for monitoring neuromuscular function, individual variability, and coexisting disease. NMBDs with rapid onset without major adverse events are expected in the next few years, and the development of lower potency NMBDs will continue. Anesthesiologists should be aware of the use of NMBDs in the management of anesthesia. The choice of NMBD and determination of the appropriate dosage to modulate neuromuscular blockade characteristics such as onset time and duration of neuromuscular blockade should be considered along with factors that affect the effects of the NMBDs. In this review, we discuss the factors that affect the onset time of NMBDs. PMID:29046769

  18. Bio-psycho-social factors affecting sexual self-concept: A systematic review

    PubMed Central

    Potki, Robabeh; Ziaei, Tayebe; Faramarzi, Mahbobeh; Moosazadeh, Mahmood; Shahhosseini, Zohreh

    2017-01-01

    Background Nowadays, it is believed that mental and emotional aspects of sexual well-being are the important aspects of sexual health. Sexual self-concept is a major component of sexual health and the core of sexuality. It is defined as the cognitive perspective concerning the sexual aspects of ‘self’ and refers to the individual’s self-perception as a sexual creature. Objective The aim of this study was to assess the different factors affecting sexual self-concept. Methods English electronic databases including PubMed, Scopus, Web of Science and Google Scholar as well as two Iranian databases including Scientific Information Database and Iranmedex were searched for English and Persian-language articles published between 1996 and 2016. Of 281 retrieved articles, 37 articles were finally included for writing this review article. Results Factors affecting sexual self-concept were categorized to biological, psychological and social factors. In the category of biological factors, age gender, marital status, race, disability and sexual transmitted infections are described. In the psychological category, the impact of body image, sexual abuse in childhood and mental health history are present. Lastly, in the social category, the roles of parents, peers and the media are discussed. Conclusion As the development of sexual self-concept is influenced by multiple events in individuals’ lives, to promotion of sexual self-concept, an integrated implementation of health policies is recommended. PMID:29038693

  19. Bio-psycho-social factors affecting sexual self-concept: A systematic review.

    PubMed

    Potki, Robabeh; Ziaei, Tayebe; Faramarzi, Mahbobeh; Moosazadeh, Mahmood; Shahhosseini, Zohreh

    2017-09-01

    Nowadays, it is believed that mental and emotional aspects of sexual well-being are the important aspects of sexual health. Sexual self-concept is a major component of sexual health and the core of sexuality. It is defined as the cognitive perspective concerning the sexual aspects of 'self' and refers to the individual's self-perception as a sexual creature. The aim of this study was to assess the different factors affecting sexual self-concept. English electronic databases including PubMed, Scopus, Web of Science and Google Scholar as well as two Iranian databases including Scientific Information Database and Iranmedex were searched for English and Persian-language articles published between 1996 and 2016. Of 281 retrieved articles, 37 articles were finally included for writing this review article. Factors affecting sexual self-concept were categorized to biological, psychological and social factors. In the category of biological factors, age gender, marital status, race, disability and sexual transmitted infections are described. In the psychological category, the impact of body image, sexual abuse in childhood and mental health history are present. Lastly, in the social category, the roles of parents, peers and the media are discussed. As the development of sexual self-concept is influenced by multiple events in individuals' lives, to promotion of sexual self-concept, an integrated implementation of health policies is recommended.

  20. Clinical trials involving cats: what factors affect owner participation?

    PubMed

    Gruen, Margaret E; Jiamachello, Katrina N; Thomson, Andrea; Lascelles, B Duncan X

    2014-09-01

    Clinical trials are frequently hindered by difficulties in recruiting eligible participants, increasing the timeline and limiting generalizability of results. In veterinary medicine, where proxy enrollment is required, no studies have detailed what factors influence owner participation in clinical trials involving cats. We aimed to investigate these factors through a survey of owners at first opinion practices. The survey was designed using feedback from a pilot study and input from clinical researchers. Owners were asked demographic questions and whether they would, would not, or were unsure about participating in a clinical trial with their cat. They then ranked the importance and influence of various factors on participation using a five-point Likert-type scale, and incentives from most to least encouraging. A total of 413 surveys were distributed to cat owners at four hospitals, two feline-only and two multi-species; 88.6% were completed. Data for importance and influence factors as well as incentive rankings were analyzed overall, and by hospital type, location and whether owners would consider participating. The most influential factors were trust in the organization, benefit to the cat and veterinarian recommendation. Importance and influence factors varied by willingness to participate. Ranked incentives were not significantly different across groups, with 'Free Services' ranked highest. This study provides a first look at what factors influence participation in clinical trials with cats. Given the importance placed in the recommendation of veterinarians, continued work is needed to determine veterinarian-related factors affecting clinical trial participation. The results provide guidance towards improved clinical trial design, promotion and education. © ISFM and AAFP 2014.

  1. Preoperative Risk Factors Associated With Poor Outcomes of Revision Surgery for "Pseudotumors" in Patients With Metal-on-Metal Hip Arthroplasty.

    PubMed

    Liow, Ming Han Lincoln; Dimitriou, Dimitris; Tsai, Tsung-Yuan; Kwon, Young-Min

    2016-12-01

    Revision surgery of failed metal-on-metal (MoM) total hip arthroplasty (THA) for adverse tissue reaction (pseudotumor) can be challenging as a consequence of soft tissue and muscle necrosis. The aims of this study were to (1) report the revision outcomes of patients who underwent revision surgery for failed MoM hip arthroplasty due to symptomatic pseudotumor and (2) identify preoperative risk factors associated with revision outcomes. Between January 2011 and January 2013, a total of 102 consecutive large head MoM hip arthroplasties in 97 patients (male: 62, female: 35), who underwent revision surgery were identified from the database of a multidisciplinary referral center. At minimum follow-up of 2 years (range: 26-52 months), at least one complication had occurred in 14 of 102 revisions (14%). Prerevision radiographic loosening (P = .01), magnetic resonance imaging (MRI) findings of solid lesions with abductor deficiency on MRI (P < .001), and intraoperative grading of adverse tissue reactions (P = .05) were correlated with post-revision complications. The reoperation rate of revised MoM THA was 7% (7 of 102 hips). Implant survivorship was 88% at 3 years. Metal ion levels declined in most patients after removal of MoM articulation. Revision outcomes of revision surgery for failed MoM THA due to symptomatic pseudotumor demonstrated 14% complication rate and 7% re-revision rate at 30-month follow-up. Our study identified prerevision radiographic loosening, solid lesions/abductor deficiency on MRI, and high grade intraoperative tissue damage as risk factors associated with poorer revision outcomes. This provides clinically useful information for preoperative planning and perioperative counseling of MoM THA patients undergoing revision surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Factors affecting smartphone adoption for accessing information in medical settings.

    PubMed

    Tahamtan, Iman; Pajouhanfar, Sara; Sedghi, Shahram; Azad, Mohsen; Roudbari, Masoud

    2017-06-01

    This study aimed to acquire knowledge about the factors affecting smartphone adoption for accessing information in medical settings in Iranian Hospitals. A qualitative and quantitative approach was used to conduct this study. Semi-structured interviews were conducted with 21 medical residents and interns in 2013 to identify determinant factors for smartphone adoption. Afterwards, nine relationships were hypothesised. We developed a questionnaire to test these hypotheses and to evaluate the importance of each factor. Structural equation modelling was used to analyse the causal relations between model parameters and to accurately identify determinant factors. Eight factors were identified in the qualitative phase of the study, including perceived usefulness, perceived ease of use, training, internal environment, personal experience, social impacts, observability and job related characteristics. Among the studied factors, perceived usefulness, personal experience and job related characteristics were significantly associated with attitude to use a smartphone which accounted for 64% of the variance in attitude. Perceived usefulness had the strongest impact on attitude to use a smartphone. The factors that emerged from interviews were consistent with the Technology Acceptance Model (TAM) and some previous studies. TAM is a reliable model for understanding the factors of smartphone acceptance in medical settings. © 2017 Health Libraries Group.

  3. Factors affecting mortality in elderly patients who underwent surgery for gastric cancer.

    PubMed

    Kayılıoglu, Selami Ilgaz; Göktug, Ufuk Utku; Dinc, Tolga; Sozen, Isa; Yavuz, Zeynep; Coskun, Faruk

    2018-03-05

    The aim of this study was to determine factors affecting overall mortality in patients over 60 years of age who underwent surgery for gastric cancer in our clinic. Data on histopathological diagnosis (tumor size, lymph node status, and number), pathological stage, serum albumin level, tumor markers, complete blood count, and demographic information of 109 patients over 60 years of age who had surgery for gastric cancer between January 2011 and July 2016 were obtained retrospectively from the patient files. In addition, the survival status of all patients were examined and recorded. Metastatic lymph node ratio (MLR), red cell distribution width platelet ratio (RPR), neutrophil-lymphocyte ratio (NLR), plateletlymphocyte ratio (PLR), and prognostic nutritional index (PNI) were calculated. On univariate analysis of independent parameters, pathological LN number (p = 0.001), MLR (p <0.001), T3 (p = 0.001) or T4 (p = 0,006) tumor stage according to TNM system, the presence of metastasis (p = 0.063), and male gender (p = 0.066) were found to affect overall mortality (OM). On multivariable Cox regression analysis of these results, MLR (p = 0.005) and T stage (p = 0.006) was determined to be a statistically significant and independent prognostic value. In patients over 60 years of age who underwent surgery for gastric cancer, the factors affecting mortality were determined to be the presence of metastases, number of pathological lymph nodes, and male gender. Metastatic lymph node ratio and T1&T2 stage were determined to be independent prognostic factors. Elderly, Gastric cancer, Mortality, Prognostic factor.

  4. Control of exogenous factors affecting plasma homovanillic acid concentration.

    PubMed

    Davidson, M; Giordani, A B; Mohs, R C; Mykytyn, V V; Platt, S; Aryan, Z S; Davis, K L

    1987-04-01

    Measurements of plasma homovanillic acid (pHVA) concentrations appear to be a valid research strategy in psychiatric disorders in which a central dopamine (DA) abnormality has been implicated. This study provides guidance about the control of some of the exogenous factors affecting pHVA concentrations. Fasting for 14 hours eliminates the dietary effects on pHVA in healthy human subjects. Changing position, walking for 30 minutes, or smoking two cigarettes has no effect on pHVA concentrations.

  5. Factors Affecting Differential Equation Problem Solving Ability of Students at Pre-University Level: A Conceptual Model

    ERIC Educational Resources Information Center

    Aisha, Bibi; Zamri, Sharifa NorulAkmar Syed; Abdallah, Nabeel; Abedalaziz, Mohammad; Ahmad, Mushtaq; Satti, Umbreen

    2017-01-01

    In this study, different factors affecting students' differential equations (DEs) solving abilities were explored at pre university level. To explore main factors affecting students' differential equations problem solving ability, articles for a 19-year period, from 1996 to 2015, were critically reviewed and analyzed. It was revealed that…

  6. Merriam's turkey nest survival and factors affecting nest predation by mammals

    Treesearch

    Chad P. Lehman; Mark A. Rumble; Lester D. Flake; Daniel J. Thompson

    2008-01-01

    Nest success is an important parameter affecting population fluctuations of wild turkeys (Meleagris gallopavo). Factors influencing mammalian predation on turkey nests are complicated and not well understood. Therefore, we assessed nest hazard risk by testing competing hypotheses of Merriam's turkey (M. g. merriami) nest...

  7. Factors that affect coseismic folds in an overburden layer

    NASA Astrophysics Data System (ADS)

    Zeng, Shaogang; Cai, Yongen

    2018-03-01

    Coseismic folds induced by blind thrust faults have been observed in many earthquake zones, and they have received widespread attention from geologists and geophysicists. Numerous studies have been conducted regarding fold kinematics; however, few have studied fold dynamics quantitatively. In this paper, we establish a conceptual model with a thrust fault zone and tectonic stress load to study the factors that affect coseismic folds and their formation mechanisms using the finite element method. The numerical results show that the fault dip angle is a key factor that controls folding. The greater the dip angle is, the steeper the fold slope. The second most important factor is the overburden thickness. The thicker the overburden is, the more gradual the fold. In this case, folds are difficult to identify in field surveys. Therefore, if a fold can be easily identified with the naked eye, the overburden is likely shallow. The least important factors are the mechanical parameters of the overburden. The larger the Young's modulus of the overburden is, the smaller the displacement of the fold and the fold slope. Strong horizontal compression and vertical extension in the overburden near the fault zone are the main mechanisms that form coseismic folds.

  8. Impurity effects in transition metal silicides

    NASA Technical Reports Server (NTRS)

    Lien, C.-D.; Nicolet, M.-A.

    1984-01-01

    Impurities can affect the properties of silicides directly by virtue of their presence. Impurities can also influence the processes by which silicides are formed. The effect of impurities on the reaction of transition metal films with a silicon substrate induced by thermal annealing are well documented. The interpretation of these results is discussed. It is shown that impurity redistribution is a major factor in determining how significant the effect of an impurity is. Redistribution observed for dopant impurities is also discussed.

  9. Multi-Level Family Factors and Affective and Behavioral Symptoms of Oppositional Defiant Disorder in Chinese Children

    PubMed Central

    Tang, Yixin; Lin, Xiuyun; Chi, Peilian; Zhou, Qing; Hou, Xiangning

    2017-01-01

    Given the important role of family environment in children's psychological development, the objective of this study was to examine the linkages between family factors at the whole, dyadic, and individual levels and two dimensions (affective and behavioral) of Oppositional Defiant Disorder (ODD) symptoms in Chinese children. Participants comprised of 80 father-child dyads and 169 mother-child dyads from families with ODD children. The results indicated that multilevel family factors were differently associated with children's affective and behavioral ODD symptoms. All the family factors at the dyadic and individual levels were significantly associated with child affective ODD symptoms. However, only the most proximal factors (parent-child relationship and child emotion regulation, which were directly related to child) were significantly related to child behavioral ODD symptoms. The present study extends the current knowledge regarding the relationships between family factors and two dimensions of child ODD symptoms by testing the comprehensive multilevel family factors model. This study also recommends that future interventions for ODD children should consider the multi-level family factors to enhance intervention efficacy. PMID:28713321

  10. Soluble organic carbon and pH of organic amendments affect metal mobility and chemical speciation in mine soils.

    PubMed

    Pérez-Esteban, Javier; Escolástico, Consuelo; Masaguer, Alberto; Vargas, Carmen; Moliner, Ana

    2014-05-01

    We evaluated the effects of pH and soluble organic carbon affected by organic amendments on metal mobility to find out the optimal conditions for their application in the stabilization of metals in mine soils. Soil samples (pH 5.5-6.2) were mixed with 0, 30 and 60 th a(-1) of sheep-horse manure (pH 9.4) and pine bark compost (pH 5.7). A single-step extraction procedure was performed using 0.005 M CaCl2 adjusted to pH 4.0-7.0 and metal speciation in soil solution was simulated using NICA-Donnan model. Sheep-horse manure reduced exchangeable metal concentrations (up to 71% Cu, 75% Zn) due to its high pH and degree of maturity, whereas pine bark increased them (32% Cu, 33% Zn). However, at increasing dose and hence pH, sheep-horse manure increased soluble Cu because of higher soluble organic carbon, whereas soluble Cu and organic carbon increased at increasing dose and correspondingly decreasing pH in pine bark and non-amended treatments. Near the native pH of these soils (at pH 5.8-6.3), with small doses of amendments, there was minimum soluble Cu and organic carbon. Pine bark also increased Zn solubility, whereas sheep-horse manure reduced it as soluble Zn always decreased with increasing pH. Sheep-horse manure also reduced the proportion of free metals in soil solution (from 41% to 4% Cu, from 97% to 94% Zn), which are considered to be more bioavailable than organic species. Sheep-horse manure amendment could be efficiently used for the stabilization of metals with low risk of leaching to groundwater at low doses and at relatively low pH, such as the native pH of mine soils. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Oxidative damage of workers in secondary metal recovery plants affected by smoking status and joining the smelting work.

    PubMed

    Chia, Taipau; Hsu, Ching Yi; Chen, Hsiu Ling

    2008-04-01

    In Taiwan, secondary copper smelters and zinc recovery plants primarily utilize recovering metal from scrap and dross, and handles mostly fly ash and slag with high temperature to produce ZnO from the iron and steel industry. The materials may contain organic impurities, such as plastic and organic chloride chemicals, and amounts of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are produced during the smelting process. Therefore, secondary metal recovery industries are major emission sources of PCDD/Fs, which may have been demonstrated to elicit oxidative stress and to involve the production of plasma malondialdehyde (MDA). Many studies have also indicated that the intake of antioxidants, smoking, age and exposure to environmental pollutants may be implicated to DNA damage or lipid peroxidation. This study therefore aims to elucidate the roles of occupational exposure like joining the smelting work, age, smoking and alcohol status, and antioxidant intake on oxidative damage in secondary metal recovery workers in Taiwan. 73 workers were recruited from 2 secondary metal recovery plants. The analysis of 8-hydroxydeoxyguanosine (8-OH-dG) in urine, DNA strand breakage (comet assay) and lipid peroxidation (MDA) in blood samples were completed for all of the workers. The results showed that the older subjects exhibited significantly lower levels of 8-OH-dG and MDA than younger subjects. Our investigation also showed that working departments were in related to plasma MDA and DNA strand breakage levels of nonsmokers, however, the observation become negligible in smokers. And it is implicated that cigarette type might affect 8-OH-dG levels in secondary metal recovery workers. Since, adding to results above, the MDA level in production workers was significantly higher than those in managerial departments, it is important for the employers to make efforts on improving occupational environments or serving protective equipments to protect workers

  12. Factors affecting compliance with measles vaccination in Lao PDR.

    PubMed

    Phimmasane, Maniphet; Douangmala, Somthana; Koffi, Paulin; Reinharz, Daniel; Buisson, Yves

    2010-09-24

    In line with WHO objectives, the Lao Government is committed to eliminate measles by 2012. Yet from 1992 to 2007, the annual incidence of measles remained high while the vaccination coverage showed a wide diversity across provinces. A descriptive study was performed to determine factors affecting compliance with vaccination against measles, which included qualitative and quantitative components. The qualitative study used a convenience sample of 13 persons in charge of the vaccination program, consisting of officials from different levels of the health care structure and members of vaccination teams. The quantitative study performed on the target population consisted of a matched, case-control survey conducted on a stratified random sample of parents of children aged 9-23 months. Overall, 584 individuals (292 cases and 292 controls) were interviewed in the three provinces selected because of low vaccination coverage. On the provision of services side (supply), the main problems identified were a lack of vaccine supply and diluent, a difficulty in maintaining the cold chain, a lack of availability and competence among health workers, a lack of coordination and a limited capacity to assess needs and make coherent decisions. In the side of the consumer (demand), major obstacles identified were poor knowledge about measles immunization and difficulties in accessing vaccination centers because of distance and cost. In multivariate analysis, a low education level of the father was a factor of non-immunization while the factors of good compliance were high incomes, spacing of pregnancies, a feeling that children must be vaccinated, knowledge about immunization age, presenting oneself to the hospital rather than expecting the mobile vaccination teams and last, immunization of other family members or friends' children. The main factors affecting the compliance with vaccination against measles in Laos involve both the supply side and the demand side. Obtaining an effective

  13. Transfer of heavy metals through terrestrial food webs: a review.

    PubMed

    Gall, Jillian E; Boyd, Robert S; Rajakaruna, Nishanta

    2015-04-01

    Heavy metals are released into the environment by both anthropogenic and natural sources. Highly reactive and often toxic at low concentrations, they may enter soils and groundwater, bioaccumulate in food webs, and adversely affect biota. Heavy metals also may remain in the environment for years, posing long-term risks to life well after point sources of heavy metal pollution have been removed. In this review, we compile studies of the community-level effects of heavy metal pollution, including heavy metal transfer from soils to plants, microbes, invertebrates, and to both small and large mammals (including humans). Many factors contribute to heavy metal accumulation in animals including behavior, physiology, and diet. Biotic effects of heavy metals are often quite different for essential and non-essential heavy metals, and vary depending on the specific metal involved. They also differ for adapted organisms, including metallophyte plants and heavy metal-tolerant insects, which occur in naturally high-metal habitats (such as serpentine soils) and have adaptations that allow them to tolerate exposure to relatively high concentrations of some heavy metals. Some metallophyte plants are hyperaccumulators of certain heavy metals and new technologies using them to clean metal-contaminated soil (phytoextraction) may offer economically attractive solutions to some metal pollution challenges. These new technologies provide incentive to catalog and protect the unique biodiversity of habitats that have naturally high levels of heavy metals.

  14. Factors affecting sexual life during pregnancy in eastern Turkey.

    PubMed

    Eryilmaz, Gülşen; Ege, Emel; Zincir, Handan

    2004-01-01

    This is a descriptive and cross-sectional study aiming to determine the factors affecting sexual life in pregnant women. The study was carried out in 238 women in Malatya, Turkey. It was found that 61.4% regarded coitus as a risk during pregnancy, 31.9% did not have any knowledge about this matter. In 81.5% sexual life was affected during pregnancy. The mean frequency of intercourse was 2.02 +/- 0.7/week before pregnancy and decreased to 1.51 +/- 0.6/week during pregnancy. The reasons for this decline are: exhaustion and fatigue (64.3%); waning of sexual desire (55.9%); harmful to the fetus (49.2%); causing abortions in early pregnancy (45%), and inducing preterm labor (34%). There was a significant relationship between changes in sexual life during pregnancy and the duration of marriage (chi2=10.8, p<0.05), education level (chi2=18.1, p<0.05), parity (chi2=11.1, p<0.05), and gravidity (chi2=6.8, p<0.05). The variables such as age, employment status, and number of abortions did not affect sexual life during pregnancy. Copyright 2004 S. Karger AG, Basel

  15. Factors Affecting Husband Participation in Antenatal Care Attendance and Delivery

    NASA Astrophysics Data System (ADS)

    Rumaseuw, R.; Berliana, S. M.; Nursalam, N.; Efendi, F.; Pradanie, R.; Rachmawati, P. D.; Aurizki, G. E.

    2018-02-01

    The government has implemented several programs to prevent and reduce a mother’s mortality rate by enhancing active role of the family. The most responsible family member on maintaining the pregnancy and delivery process is the husband. The husband must be active to take care of his wife. Active participation of the husband in accompanying his wife during pregnancy and the delivery process is one of the substantial factors, which helps the husband to take decisions related to the health of his wife. This study aimed to identify variables and its trends, which significantly affect a husband’s participation in accompanying his wife during pregnancy and the delivery process. The data used in this study was from an Indonesian Demographic Health Survey 2012. The study used binary logistic regression as the analysis method. The result showed as many as 8,237 husbands accompanied their wife in antenatal care and the delivery process. The significant variables affecting the husband participation are the age of the wife, the education of wife, the education of the husband, the occupational status of the wife and the husband, the number of children, pregnancy status, and residency region. The possibility for a husband to accompany his wife is larger in several factors, such as the wife being between the ages of 21 - 35 years old, a husband who minimally graduated from junior high school, a working husband, as well as a wife, and the number of children less than and equal to two and the expected pregnancy. The government should consider those factors to create policy related women’s health and integrate the factors into various sectors.

  16. Milking performance evaluation and factors affecting milking claw vacuum levels with flow simulator.

    PubMed

    Enokidani, Masafumi; Kawai, Kazuhiro; Shinozuka, Yasunori; Watanabe, Aiko

    2017-08-01

    Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high-producing cows. This study used a simulated milking device to examine the milking performance of the milking system of 73 dairy farms and to analyze the factors affecting claw vacuum. Mean claw vacuum and range of fluctuation of claw vacuum (claw vacuum range) were measured at three different flow rates: 5.7, 7.6 and 8.7 kg/min. At the highest flow rate, only 16 farms (21.9%) met both standards of mean claw vacuum ≥35 kPa and claw vacuum range ≤ 7 kPa, showing that milking systems currently have poor milking performance. The factors affecting mean claw vacuum were claw type, milk-meter and vacuum shut-off device; the factor affecting claw vacuum range was claw type. Examination of the milking performance of the milking system using a simulated milking device allows an examination of the performance that can cope with high producing cows, indicating the possibility of reducing the risk of mastitis caused by inappropriate claw vacuum. © 2016 Japanese Society of Animal Science.

  17. Factors that Affect Emergent Literacy Development When Engaging with Electronic Books

    ERIC Educational Resources Information Center

    Salmon, Lynda G.

    2014-01-01

    This article reviews extant literature with the purpose of identifying factors that affect the potential efficacy of electronic books to support literacy development during early childhood. Selection criteria include experimental, quasi-experimental, and observational studies from peer-reviewed journals from 2000 to 2013 with a target population…

  18. How Metal Substitution Affects the Enzymatic Activity of Catechol-O-Methyltransferase

    PubMed Central

    Sparta, Manuel; Alexandrova, Anastassia N.

    2012-01-01

    Catechol-O-methyltransferase (COMT) degrades catecholamines, such as dopamine and epinephrine, by methylating them in the presence of a divalent metal cation (usually Mg(II)), and S-adenosyl-L-methionine. The enzymatic activity of COMT is known to be vitally dependent on the nature of the bound metal: replacement of Mg(II) with Ca(II) leads to a complete deactivation of COMT; Fe(II) is slightly less than potent Mg(II), and Fe(III) is again an inhibitor. Considering the fairly modest role that the metal plays in the catalyzed reaction, this dependence is puzzling, and to date remains an enigma. Using a quantum mechanical / molecular mechanical dynamics method for extensive sampling of protein structure, and first principle quantum mechanical calculations for the subsequent mechanistic study, we explicate the effect of metal substitution on the rate determining step in the catalytic cycle of COMT, the methyl transfer. In full accord with experimental data, Mg(II) bound to COMT is the most potent of the studied cations and it is closely followed by Fe(II), whereas Fe(III) is unable to promote catalysis. In the case of Ca(II), a repacking of the protein binding site is observed, leading to a significant increase in the activation barrier and higher energy of reaction. Importantly, the origin of the effect of metal substitution is different for different metals: for Fe(III) it is the electronic effect, whereas in the case of Ca(II) it is instead the effect of suboptimal protein structure. PMID:23056605

  19. Motivating Factors that Affect Enrolment and Student Performance in an ODL Engineering Program

    ERIC Educational Resources Information Center

    Dadigamuwa, P. R.; Senanayake, Samans

    2012-01-01

    The present study was carried out to determine the motivating factors for enrolling in an engineering study programme in open and distance learning (ODL) and the factors that affect the students' performance. The study was conducted with two convenient samples of students following distance learning courses in engineering technology, conducted by…

  20. Does fish reproduction and metabolic activity influence metal levels in fish intestinal parasites, acanthocephalans, during fish spawning and post-spawning period?

    PubMed

    Filipović Marijić, Vlatka; Vardić Smrzlić, Irena; Raspor, Biserka

    2014-10-01

    Application of fish intestinal parasites, acanthocephalans, as bioindicators in metal exposure assessment usually involves estimation of their metal levels and bioconcentration factors. Metal levels in parasite final host, fishes, are influenced by fish physiology but there is no data for acanthocephalan metal levels. Gastrointestinal Zn, Fe, Mn, Cd, Ag levels in European chub (Squalius cephalus L.) from the Sava River were significantly higher during chub spawning (April/May) compared to the post-spawning period (September). In acanthocephalans (Pomphorhynchus laevis and Acanthocephalus anguillae) significantly higher metal levels during chub spawning were observed only for Zn in P. laevis. Bioconcentration factors were twice as high for Fe, Mn, Ag, Pb in the post-spawning period, probably as a consequence of lower gastrointestinal metal levels in fish rather than metal exposure. Therefore, bioconcentration factors should be interpreted with caution, due to their possible variability in relation to fish physiology. In addition, gastrointestinal Cu, Cd and Pb levels were lower in infected than uninfected chub, indicating that metal variability in fishes might be affected by the presence of acanthocephalans. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. A review of genetic, biological, pharmacological, and clinical factors that affect carbohydrate-deficient transferrin levels.

    PubMed

    Fleming, Michael F; Anton, Raymond F; Spies, Claudia D

    2004-09-01

    Carbohydrate-deficient transferrin (CDT) is an alcohol biomarker recently approved by the U.S. Food and Drug Administration. This test is increasingly being used to detect and monitor alcohol use in a variety of health care, legal, and industrial settings. The goal of this study is to review the genetic, biological, pharmacological, and clinical factors that may affect CDT levels. A review of the literature identified 95 research articles that met the authors' criteria and reported potential interactions of a variety of factors on percent and total CDT levels. The review established 12 categories of variables that may affect CDT levels. These categories include (1) alcohol use, (2) genetic factors, (3) race, (4) gender, (5) age, (6) liver disease, (7) iron levels, (8) tobacco use, (9) medication such as estrogen and anticonvulsants, (10) metabolic factors such as body mass index and total body water, (11) chronic medical conditions such as rheumatoid arthritis, and (12) surgical patients. There is evidence that %CDT levels are affected by alcohol use, end-stage liver disease, and genetic variants. In addition to these three factors, total CDT levels (CDTect) are also affected by factors that raise transferrin levels such as iron deficiency, chronic illnesses, and menopausal status. Other potential factors such as tobacco and age appear to be confounded by alcohol use. The roles of female gender, low body mass index, chronic inflammatory diseases, and medication on CDT levels require further study. False negatives are associated with female gender, episodic lower level alcohol use, and acute trauma with blood loss. This review suggests that a number of factors are associated with false-positive CDTect and %CDT levels. CDT offers great promise to assist physicians in the care of patients to detect and monitor heavy alcohol use.

  2. Comparison of SP-LIBS and DP-LIBS on metal and non-metal testing based on LIBS

    NASA Astrophysics Data System (ADS)

    Lin, Xiaomei; Sun, Haoran; Lin, Jingjun

    2017-10-01

    Laser-induced breakdown spectroscopy (LIBS) technology for metal and nonmetallic detection accuracy is the key technology to be solved in LIBS measurement, Due to metal elements and non-metallic elements in the lively, atomic structure and the degree of excitation of the laser are totally different, so the laser induced plasma evolution and spectral intensity are absolutely different. Among the many factors that affect measurement accuracy, the single and double pulse of the laser has a great influence on the measurement accuracy of metal and non-metal, they both have their own advantages, but also have their own shortcomings. In order to compare the effect of SP-LIBS and DP-LIBS on the measurement results of different elements, in this experiment, we put the metal element aluminum and non-metallic element carbon as the sample, the laser energy as a variable, using the high-speed camera shooting SP- LIBS and DP- LIBS plasma images. Using the spectral analyzer to record the spectral intensity of the elements, by calculating the relative RSD of the signal intensity and comparing the spectral intensity and the signal stability for different elements, develop an optimized experimental program. The experimental results show that under the same energy condition, the metal aluminum ion image under the DP- LIBS and the non-metallic carbon ion image under the SP- LIBS are the most suitable images. By considering the stability of the line intensity and the signal stability, we find that the sensitivity and stability of the signal strength of the metal elements under the double pulse are better than that of the single pulse, and for the non-metallic element, the single pulse laser is better than the double pulse.

  3. Factors Affecting Teachers' Adoption of Educational Computer Games: A Case Study

    ERIC Educational Resources Information Center

    Kebritchi, Mansureh

    2010-01-01

    Even though computer games hold considerable potential for engaging and facilitating learning among today's children, the adoption of modern educational computer games is still meeting significant resistance in K-12 education. The purpose of this paper is to inform educators and instructional designers on factors affecting teachers' adoption of…

  4. Factors Affecting Participation of Displaced Workers in Retraining: A Literature Review.

    ERIC Educational Resources Information Center

    Dean, Gary J.

    This document offers a selected review of literature relevant to retraining displaced workers. A description of the economic conditions leading to the displacement of workers, the nature and scope of the displaced worker problem, and factors potentially affecting displaced workers' participation in adult education and training programs is…

  5. Factors Affecting Student Retention in Online Courses: Overcoming This Critical Problem

    ERIC Educational Resources Information Center

    Gaytan, Jorge

    2013-01-01

    The purpose of this study was to determine what a panel of 15 experts would identify as critical factors affecting student retention in online courses that will serve as implications for educational leaders to guide their student retention strategies, online organizational structures, institutional policies, and online instructional activities. A…

  6. Factors Affecting Bachelor's Degree Completion among Black Males with Prior Attrition

    ERIC Educational Resources Information Center

    Matthews-Whetstone, Rayna; Scott, Joyce A.

    2015-01-01

    Black males lag behind their female counterparts in bachelor's degree completion. This study examined why Black males leave higher education, eventually return, and complete their degrees. Researchers are aware of some of the challenges that Black males encounter in higher education, but there is little information factors affecting successful…

  7. Factors Affecting Career Choice among Speech-Language Pathology and Audiology Students

    ERIC Educational Resources Information Center

    Stone, Larissa; Pellowski, Mark W.

    2016-01-01

    This investigation assessed the factors affecting career choice among 474 current undergraduate and graduate speech-language pathology and audiology students (from four universities). A 14-item questionnaire was developed that included questions related to general influence of career choice and whether or not the participants had previously been,…

  8. Factors affecting the decision to pursue glaucoma fellowship training.

    PubMed

    Gedde, Steven J; Budenz, Donald L; Haft, Payman; Lee, Yunhee; Quigley, Harry A

    2007-01-01

    To identify factors associated with the choice to pursue glaucoma fellowship training by graduating ophthalmology residents. An anonymous survey was sent to each graduating ophthalmology resident in the United States in February 2003. Demographic data and information relating to residency training, career goals, and factors influencing career choices were collected from the surveys. Surveys were completed by 215 (49.2%) residents, including 135 (62.8%) who were pursuing fellowships. Among residents undertaking fellowship training, 17 (12.6%) selected glaucoma and 118 (87.4%) chose other subspecialties. Residents entering glaucoma fellowships performed more glaucoma filtering procedures (P=0.006), and they were less likely to publish a paper (P=0.05) and have time allocated for research (P=0.04) than residents seeking fellowships in other subspecialties. Factors that were rated as less important to those choosing glaucoma fellowships included interest in challenging diagnostic problems (P=0.009), types of patient problems (P=0.015), an academic career (P=0.03), and working with new technology (P=0.04). The decision to pursue fellowship training was made later by residents entering glaucoma compared with those choosing other subspecialties (P=0.001). A variety of factors affect the decision to pursue fellowship training. There are differences in how these factors are weighed among residents seeking fellowships in glaucoma and other subspecialties.

  9. An Analysis of Multiple Factors Affecting Retention in Web-Based Community College Courses

    ERIC Educational Resources Information Center

    Doherty, William

    2006-01-01

    The current study examined four factors affecting retention in Web-based community college courses. Analyses were conducted on student demographics, student learning styles, course communication and external factors. The results suggest that Web-based courses are more attractive to busy students who are also more likely to fail or drop the course.…

  10. Some factors affecting skin and wound healing.

    PubMed

    Winter, G D

    2006-05-01

    The domestic pig is the preferred animal for studying the effects of environmental factors on skin and wound because its integument is more like that of man than any other. The three factors that most drastically affect the pattern, speed and quality of healing are dehydration of exposed tissues, the status of the blood supply bringing oxygen and nutrients to the area and sepsis. Wounds exposed to the air lose water vapour, the upper dermis dries and healing takes place beneath a dry scab. Covering a wound with an occlusive dressing prevents scab formation and radically alters the pattern of epidermal wound healing. Blowing on wounds creates a scab within three hours instead of the normal 24 hours but more tissue is sacrificed in the process. This may only be justified if it can be shown that rapid artificial scab formation significantly cuts down the incidence of severe infections, i.e. in large burns. Less serious wounds heal faster when covered with a suitable occlusive dressing. Indolent wounds are characterised by a rim of infected, necrotic tissue in which leucocytes and macrophages are unable to function effectively through lack of oxygen. A suitable dressing changed frequently can bring about mild debridement and re-establish the conditions for healing.

  11. A Study on Factors Affecting Navy Officers’ Decisions to Pursue Funded Graduate Education: A Qualitative Approach

    DTIC Science & Technology

    2017-06-01

    Distribution is unlimited. A STUDY ON FACTORS AFFECTING NAVY OFFICERS’ DECISIONS TO PURSUE FUNDED GRADUATE EDUCATION: A QUALITATIVE APPROACH ...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release. Distribution is unlimited. A STUDY ON FACTORS...REPORT DATE June 2017 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE A STUDY ON FACTORS AFFECTING NAVY OFFICERS

  12. Recovery of high-purity metallic Pd from Pd(II)-sorbed biosorbents by incineration.

    PubMed

    Won, Sung Wook; Lim, Areum; Yun, Yeoung-Sang

    2013-06-01

    This work reports a direct way to recover metallic palladium with high purity from Pd(II)-sorbed polyethylenimine-modified Corynebacterium glutamicum biosorbent using a combined method of biosorption and incineration. This study is focused on the incineration part which affects the purity of recovered Pd. The incineration temperature and the amount of Pd loaded on the biosorbent were considered as major factors in the incineration process, and their effects were examined. The results showed that both factors significantly affected the enhancement of the recovery efficiency and purity of the recovered Pd. SEM-EDX and XRD analyses were used to confirm that Pd phase existed in the ash. As a result, the recovered Pd was changed from PdO to zero-valent Pd as the incineration temperature was increased from 600 to 900°C. Almost 100% pure metallic Pd was recovered with recovery efficiency above 99.0% under the conditions of 900°C and 136.9 mg/g. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Analysis of various factors affecting pupil size in patients with glaucoma.

    PubMed

    Park, Ji Woong; Kang, Bong Hui; Kwon, Ji Won; Cho, Kyong Jin

    2017-09-16

    Pupil size is an important factor in predicting post-operative satisfaction. We assessed the correlation between pupil size, measured by Humphrey static perimetry, and various affecting factors in patients with glaucoma. In total, 825 eyes of 415 patients were evaluated retrospectively. Pupil size was measured with Humphrey static perimetry. Comparisons of pupil size according to the presence of glaucoma were evaluated, as were correlations between pupil size and various factors, including age, logMAR best corrected visual acuity (BCVA), retinal nerve fiber layer (RNFL) thickness, spherical equivalent, intraocular pressure, axial length, central corneal thickness, white-to-white, and the kappa angle. Pupil size was significantly smaller in glaucoma patients than in glaucoma suspects (p < 0.001) or the normal group (p < 0.001). Pupil size decreased significantly as age (p < 0.001) and central cornea thickness (p = 0.007) increased, and increased significantly as logMAR BCVA (p = 0.02) became worse and spherical equivalent (p = 0.007) and RNFL thickness (p = 0.042) increased. In patients older than 50 years, pupil size was significantly larger in eyes with a history of cataract surgery. Humphrey static perimetry can be useful in measuring pupil size. Pupil size was significantly smaller in eyes with glaucoma. Other factors affecting pupil size can be used in a preoperative evaluation when considering cataract surgery or laser refractive surgery.

  14. FACTORS AFFECTING SENSITIVITY OF CHEMICAL AND ECOLOGICAL RESPONSES OF MARINE EMBAYMEMTS TO NITROGEN LOADING

    EPA Science Inventory

    This paper summarizes an ongoing examination of the primary factors that affect sensitivity of marine embayment responses to nitrogen loading. Included is a discussion of two methods for using these factors: classification of embayments into discrete sensitivity classes and norma...

  15. Evaluation of factors that affect hip moment impulse during gait: A systematic review.

    PubMed

    Inai, Takuma; Takabayashi, Tomoya; Edama, Mutsuaki; Kubo, Masayoshi

    2018-03-01

    Decreasing the daily cumulative hip moments in the frontal and sagittal planes may lower the risk of hip osteoarthritis. Therefore, it may be important to evaluate factors that affect hip moment impulse during gait. It is unclear what factors affect hip moment impulse during gait. This systematic review aimed to evaluate different factors that affect hip moment impulse during gait in healthy adults and patients with hip osteoarthritis. Four databases (Scopus, ScienceDirect, PubMed, and PEDro) were searched up to August 2017 to identify studies that examined hip moment impulse during gait. Data extracted for analysis included the sample size, age, height, body mass, type of intervention, and main findings. After screening, 10 of the 975 studies identified were included in our analysis. Several factors, including a rocker bottom shoe, FitFlop™ sandals, ankle push-off, posture, stride length, body-weight unloading, a rollator, walking poles, and a knee brace, were reviewed. The main findings were as follows: increasing ankle push-off decreased both the hip flexion and extension moment impulses; body-weight unloading decreased both the hip extension and adduction moment impulses; the FitFlop™ sandal increased the sum of the hip flexion and extension moment impulses; long strides increased the hip extension moment impulse; and the use of a knee brace increased hip flexion moment impulse. Of note, none of the eligible studies included patients with hip osteoarthritis. The hip moment impulses can be modified by person-specific factors (ankle push-off and long strides) and external factors (body-weight unloading and use of the FitFlop™ sandals and a knee brace). Effects on the progression of hip osteoarthritis remain to be evaluated. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Factors Affecting University Students' Intention to Use Cloud Computing in Jordan

    ERIC Educational Resources Information Center

    Rababah, Khalid Ali; Khasawneh, Mohammad; Nassar, Bilal

    2017-01-01

    The aim of this study is to examine the factors affecting students' intention to use cloud computing in the Jordanian universities. To achieve this purpose, a quantitative research approach which is a survey-based was deployed. Around 400 questionnaires were distributed randomly to Information Technology (IT) students at four universities in…

  17. Factors Affecting Early Services for Children Who Are Hard of Hearing

    ERIC Educational Resources Information Center

    Harrison, Melody; Page, Thomas A.; Oleson, Jacob; Spratford, Meredith; Berry, Lauren Unflat; Peterson, Barbara; Welhaven, Anne; Arenas, Richard M.; Moeller, Mary Pat

    2016-01-01

    Purpose: To describe factors affecting early intervention (EI) for children who are hard of hearing, we analyzed (a) service setting(s) and the relationship of setting to families' frequency of participation, and (b) provider preparation, caseload composition, and experience in relation to comfort with skills that support spoken language for…

  18. Factors Affecting Training Transfer: Participants' Motivation to Transfer Training, Literature Review

    ERIC Educational Resources Information Center

    Alawneh, Muhammad K.

    2008-01-01

    This article investigates factors that motivate participants in learning and training activities to transfer skills, knowledge and attitude from the learning setting to the workplace. Based on training transfer theories hypothesized by Holton (1996), one of the major theories that affect an organization's learning is motivation to transfer theory.…

  19. Long-term adequacy of metal resources

    USGS Publications Warehouse

    Singer, D.A.

    1977-01-01

    Although the earth's crust contains vast quantities of metals, extraction technologies and associated costs are inextricably bound to three fundamental geological factors - the amount of metal available in the earth's crust in each range of grades, the mineralogical form and chemical state of the metal, and the spatial distribution of the metal. The energy required to recover a given amount of metal increases substantially as grade declines. Most metal is produced from sulphide or oxide minerals, whereas most metal in the crust may be locked in the structures of the more refractory silicates. Recovery from silicate minerals could require orders of magnitude more energy than that used at present as also could exploitation of small, widely scattered or thin, deeply buried deposits. Although specific information on the fundamental factors is not available, each factor must in turn tend to further restrict exploitation. Independence of average grade and tonnage for many deposit types further reduces the availability of rock as a source of metal. In the long term, effects of these factors will be large increases in price for many metals. ?? 1977.

  20. The Factors that Affect Science Teachers' Participation in Professional Development

    NASA Astrophysics Data System (ADS)

    Roux, Judi Ann

    Scientific literacy for our students and the possibilities for careers available in Science, Technology, Engineering, and Mathematics (STEM) areas are important topics for economic growth as well as global competitiveness. The achievement of students in science learning is dependent upon the science teachers' effectiveness and experienced science teachers depend upon relevant professional development experiences to support their learning. In order to understand how to improve student learning in science, the learning of science teachers must also be understood. Previous research studies on teacher professional development have been conducted in other states, but Minnesota science teachers comprised a new and different population from those previously studied. The purpose of this two-phase mixed methods study was to identify the current types of professional development in which experienced, Minnesota secondary science teachers participated and the factors that affect their participation in professional development activities. The mixed-methods approach s utilized an initial online survey followed by qualitative interviews with five survey respondents. The results of the quantitative survey and the qualitative interviews indicated the quality of professional development experiences and the factors which affected the science teachers' participation in professional development activities. The supporting and inhibiting factors involved the availability of resources such as time and money, external relationships with school administrators, teacher colleagues, and family members, and personal intrinsic attributes such as desires to learn and help students. This study also describes implications for science teachers, school administrators, policymakers, and professional development providers. Recommendations for future research include the following areas: relationships between and among intrinsic and extrinsic factors, science-related professional development activities

  1. Anaerobes into heavy metal: Dissimilatory metal reduction in anoxic environments

    USGS Publications Warehouse

    Lovley, D.R.

    1993-01-01

    Within the last decade, a novel form of microbial metabolism of major environmental significance has been elucidated. In this process, known as dissimilatory metal reduction, specialized microorganisms, living in anoxic aquatic sediments and ground water, oxidize organic compounds to carbon dioxide with metals serving as the oxidant. Recent studies have demonstrated that this metabolism explains a number of important geochemical phenomena in ancient and modern sedimentary environments, affecting not only the cycling of metals but also the fate of organic matter. Furthermore, this metabolism may have practical application in remediation of environments contaminated with toxic metals and/or organics.

  2. Factors affecting the adoption of home-heating energy-conservation measures: a behavioral approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Macey, S.M.

    1982-01-01

    The basic aim of this research is to better understand homeowners' adoption of home-heating energy-conservation measures by analyzing a number of factors that are thought to be underlying determinants of adoption behavior. The basic approach is behavioral drawing on the knowledge built up in behavioral geography through studies on natural hazards and innovation diffusion, and borrowing from psychological theories of attitude formation and decision making. In particular, six factors (information, environmental personality, socio-economic and demographic factors, dwelling unit characteristics, psychological variables, and past experience) are shown to directly and indirectly affect adoption behavior. By this means, differences between adopters andmore » nonadopters in the underlying cognitive structures and in the situational factors that affect their decisions are identified. The study focuses on the adoption of three measures: reducing winter night-time thermostat settings, changing or cleaning furnace filters, and installing an automatic setback thermostat. Personal interviews with a random sample of 159 homeowners in Decatur, Illinois serve as the main data base. Results indicate that adoption behavior is determined more by past experience, than by intention. Beliefs, attitudes, and social influences affect behavior indirectly through intention. These psychological variables also act as mediators between information, knowledge, environmental personality, situational variables and behavior. In particular, respondent's age, previous home ownership, and length of residence act indirectly on adoption behavior. Each of these reflects the amount of past experience the respondent is likely to have.« less

  3. Impact of heavy metals on the female reproductive system.

    PubMed

    Rzymski, Piotr; Tomczyk, Katarzyna; Rzymski, Pawel; Poniedziałek, Barbara; Opala, Tomasz; Wilczak, Maciej

    2015-01-01

    It has been recognized that environmental pollution can affect the quality of health of the human population. Heavy metals are among the group of highly emitted contaminants and their adverse effect of living organisms has been widely studied in recent decades. Lifestyle and quality of the ambient environment are among these factors which can mainly contribute to the heavy metals exposure in humans. A review of literature linking heavy metals and the female reproductive system and description of the possible associations with emission and exposure of heavy metals and impairments of female reproductive system according to current knowledge. The potential health disorders caused by chronic or acute heavy metals toxicity include immunodeficiency, osteoporosis, neurodegeneration and organ failures. Potential linkages of heavy metals concentration found in different human organs and blood with oestrogen-dependent diseases such as breast cancer, endometrial cancer, endometriosis and spontaneous abortions, as well as pre-term deliveries, stillbirths and hypotrophy, have also been reported. Environmental deterioration can lead to the elevated risk of human exposure to heavy metals, and consequently, health implications including disturbances in reproduction. It is therefore important to continue the investigations on metal-induced mechanisms of fertility impairment on the genetic, epigenetic and biochemical level.

  4. Dietary factors affecting susceptibility to urinary tract infection.

    PubMed

    Kontiokari, Tero; Nuutinen, Matti; Uhari, Matti

    2004-04-01

    Urinary tract infection (UTI) is usually an ascending infection caused by bacteria derived from stools. Since the bacterial composition of stools is dependent on the diet, it is likely that the risk of UTI will change with changes in the diet. Most data describing diet as a risk factor for UTI come from epidemiological and interventional trials. It has been shown in a case-control setting that frequent consumption of fresh berry or fruit juices and fermented milk products containing probiotic bacteria decreases the risk for UTI recurrence in women. Several interventional trials have found Vaccinium berry products to provide protection from UTI recurrence. Probiotics have not been able to prevent UTI in interventional trials. However, the lack of an effect may be related to too low a dose or to the use of non-optimal products in these trials. Limited data are available on the effects of nutrition on UTI in children. However, there is no reason to expect that children would be different from adults in this respect. In this review, we discuss the dietary factors affecting the susceptibility to UTI.

  5. Toxic metal interactions affect the bioaccumulation and dietary intake of macro- and micro-nutrients.

    PubMed

    Khan, Anwarzeb; Khan, Sardar; Alam, Mehboob; Khan, Muhammad Amjad; Aamir, Muhammad; Qamar, Zahir; Ur Rehman, Zahir; Perveen, Sajida

    2016-03-01

    The present study was conducted to evaluate the effects of heavy metals (cadmium (Cd), lead (Pb) and Cd-Pb mix) on bioaccumulation of different nutrients. Three plant species including potato, tomato and lettuce were grown in pots containing soil contaminated with Cd, Pb and Cd-Pb mix at four different levels. The edible portions of each plant were analysed for Cd, Pb and different macro- and micro-nutrients including protein, vitamin C, nitrogen (N), phosphorous (P), potassium (K), iron (Fe), manganese (Mn), calcium (Ca) and magnesium (Mg). Results indicated significant variations in selected elemental concentrations in all the three plants grown in different treatments. The projected daily dietary intake values of selected metals were significant (P < 0.001) for Fe, Mn, Ca and Mg but not significant for protein, vitamin C, N and P. The elemental contribution to Recommended Dietary Allowance (RDA) was significant for Mn. Similarly, Fe and Mg also showed substantial contribution to RDA, while Ca, N, P, K, protein and vitamin C showed the minimal contribution for different age groups. This study suggests that vegetables cultivated on Cd and Pb contaminated soil may significantly affect their quality, and the consumption of such vegetables may result in substantial negative effects on nutritional composition of the consumer body. Long term and continuous use of contaminated vegetables may result in malnutrition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Factors affecting participation decision and amount of physical activity among urban dwellers in Malaysia.

    PubMed

    Cheah, Y K; Azahadi, M; Phang, S N; Hazilah, N

    2017-05-01

    The rapid rise in the prevalence of physical inactivity-related diseases has become a serious public health issue worldwide. The objective of the present study is to examine the factors affecting participation in physical activity among urban dwellers in Malaysia. This cross-sectional study measures physical activity using a rigorous regression model. Data are obtained from the National Health and Morbidity Survey 2011 (NHMS 2011). A lognormal hurdle model is used to analyse the participation decision and the amount decision of physical activity. The results show that income, gender, ethnicity, marital status and employment status are significantly associated with participation decision and amount decision. However, age, insurance and self-rated health only affect participation decision, whereas family size, education and smoking only affect amount decision. It can, thus, be concluded that sociodemographic, insurance, lifestyle and health factors play an important role in determining physical activity behaviour among urban dwellers. When formulating policies, special attention must be paid to these factors. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  7. Factors affecting songbird nest survival in riparian forests in a Midwestern agricultural landscape

    Treesearch

    Rebecca G. Peak; Frank R. Thompson; Terry L. Shaffer

    2004-01-01

    We investigated factors affecting nest success of songbirds in riparian forest and buffers in northeastern Missouri. We used an information-theoretic approach to determine support for hypotheses concerning effects of nest-site, habitat-patch, edge, and temporal factors on nest success of songbirds in three narrow (55-95 m) and three wide (400-530 m) riparian forests...

  8. Temporal variations and spatial distributions of heavy metals in a wastewater-irrigated soil-eggplant system and associated influencing factors.

    PubMed

    Ai, Shiwei; Liu, Bailin; Yang, Ying; Ding, Jian; Yang, Wenzhi; Bai, Xiaojuan; Naeem, Sajid; Zhang, Yingmei

    2018-05-30

    Heavy metal pollution in farmlands is highly concerned as crops' easy-uptake of heavy metal can ultimately affect consumers. In order to offer suggestions on cultivating safe quality vegetable, specifically eggplant which is widely consumed for its nutritional value and antioxidant activity, a field study was undertaken to investigate the temporal variations and spatial distributions of heavy metals in a wastewater-irrigated soil-eggplant system. In the present study, eggplants were planted in the farmlands of Weichuan village (WC) (relatively unpolluted field), Liangzhuang village (LZ) (moderately polluted field) and Minqin village (MQ) (seriously polluted field) to elucidate their temporal uptake processes of heavy metals described by the sigmoid model. Eggplant tissues from severely polluted farmlands were found with higher heavy metal concentrations and lower yields compared with other two groups. What is more, 25 farmlands along the Dongdagou stream (heavy metals polluted stream) were chosen to analyze the spatial distribution of heavy metals in soils and eggplants. Heavy metal concentrations in eggplants decreased with the decline of heavy metal concentrations in soil from upstream (pollution source) to downstream. Moreover, several methods were employed to assess bioavailability of heavy metals in soils. All the bioavailable heavy metals were found in linear positive correlations with heavy metal concentrations. Meanwhile, linear correlations were found between heavy metals in soils and eggplants. At last, redundancy analysis was used to investigate the effects of soil properties (pH, organic matter and texture of soils) and heavy metals on eggplants' uptake. The results indicated that soil heavy metals had a dominant impact on their accumulations in eggplant fruit, with a variance contribution of 78.0%, while soil properties had a regulatory effect, with a variance contribution of 5.2%. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Multilevel metallization method for fabricating a metal oxide semiconductor device

    NASA Technical Reports Server (NTRS)

    Hollis, B. R., Jr.; Feltner, W. R.; Bouldin, D. L.; Routh, D. E. (Inventor)

    1978-01-01

    An improved method is described of constructing a metal oxide semiconductor device having multiple layers of metal deposited by dc magnetron sputtering at low dc voltages and low substrate temperatures. The method provides multilevel interconnections and cross over between individual circuit elements in integrated circuits without significantly reducing the reliability or seriously affecting the yield.

  10. Atmospheric Deposition of Heavy Metals in Soil Affected by Different Soil Uses of Southern Spain

    NASA Astrophysics Data System (ADS)

    Acosta, J. A.; Faz, A.; Martínez-Martínez, S.; Bech, J.

    2009-04-01

    Heavy metals are a natural constituent of rocks, sediments and soils. However, the heavy metal content of top soils is also dependent on other sources than weathering of the indigenous minerals; input from atmospheric deposition seems to be an important pathway. Atmospheric deposition is defined as the process by which atmospheric pollutants are transferred to terrestrial and aquatic surfaces and is commonly classified as either dry or wet. The interest in atmospheric deposition has increased over the past decade due to concerns about the effects of deposited materials on the environment. Dry deposition provides a significant mechanism for the removal of particles from the atmosphere and is an important pathway for the loading of heavy metals into the soil ecosystem. Within the last decade, an intensive effort has been made to determine the atmospheric heavy metal deposition in both urban and rural areas. The main objective of this study was to identification of atmospheric heavy metals deposition in soil affected by different soil uses. Study area is located in Murcia Province (southeast of Spain), in the surroundings of Murcia City. The climate is typically semiarid Mediterranean with an annual average temperature of 18°C and precipitation of 350 mm. In order to determine heavy metals atmospheric deposition a sampling at different depths (0-1 cm, 1-5 cm, 5-15 cm and 15-30 cm) was carried out in 7 sites including agricultural soils, two industrial areas and natural sites. The samples were taken to the laboratory where, dried, passed through a 2 mm sieve, and grinded. For the determination of the moisture the samples were weighed and oven dried at 105 °C for 24 h. The total amounts of metals (Pb, Cu, Pb, Zn, Cd, Mn, Ni and Cr) were determined by digesting the samples with nitric/perchoric acids and measuring with ICP-MS. Results showed that zinc contamination in some samples of industrial areas was detected, even this contamination reaches 30 cm depth; thus it is

  11. Factors Affecting the Adoption of Information and Communication Technologies in Teaching

    ERIC Educational Resources Information Center

    Salinas, Álvaro; Nussbaum, Miguel; Herrera, Oriel; Solarte, Mario; Aldunate, Roberto

    2017-01-01

    This study describes the level of adoption of information and communication technologies in teaching in three Latin American countries. It also analyzes factors that affect the process by which teachers incorporate these technologies into their classrooms. In order to do so, an online survey was conducted with 89 teachers. The results show that…

  12. Factors affecting the healing of pressure ulcers in a Korean acute care hospital.

    PubMed

    Sung, Young Hee; Park, Kyung Hee

    2011-01-01

    We sought to determine the factors affecting pressure ulcer (PU) healing in an acute care facility in Korea. Data were collected between October 1, 2006, and September 30, 2007, regarding PU status and factors hypothesized to influence wound healing. We developed a form that queried factors thought to affect PU healing based on literature review. We also administered the Pressure Ulcer Scale for Healing (PUSH) tool to assess healing of PUs and calculated change in PUSH scale as the outcome variable reflecting the magnitude of the healing of PU. One hundred fifty eight patients with a total of 326 PUs in an acute care hospital located in Seoul, Korea, comprised the sample. The variables found to significantly affect PU healing included mean arterial pressure (MAP), serum albumin level, urinary incontinence, consultation with nutritionist, Braden Scale scale, wound size, and exudate amount. Pressure ulcer healing was improved when the MAP was higher (B = 0.034) and the serum albumin level was more than 2.8 g/dL (20.8 grams/liter) (B = 1.107). When managing patients in an acute care setting, PU healing may be improved by maintaining MAP and providing protein supplements to keep serum albumin level greater than 2.8 g/dL (20.8 grams/liter).

  13. Factors affecting aging cognitive function among community-dwelling older adults.

    PubMed

    Kim, Chun-Ja; Park, JeeWon; Kang, Se-Won; Schlenk, Elizabeth A

    2017-08-01

    The study purpose was to determine factors affecting aging cognitive function of 3,645 community-dwelling older adults in Korea. The Hasegawa Dementia Scale assessed aging cognitive function, blood analyses and anthropometrics assessed cardio-metabolic risk factors, and the Geriatric Depression Scale Short Form Korean Version assessed depressive symptoms. Participants with poor aging cognitive function were more likely to be in the late age group (≥75 y) and currently smoking and have a medical history of stroke, high body mass index, and high level of depressive symptoms; they were also less likely to engage in regular meals and physical activities. Regular meals and physical activities may be primary factors for clinical assessment to identify older adults at risk for aging cognitive function. With aging, depressive symptoms and other unhealthy lifestyle behaviours should be managed to prevent cognitive function disorders. © 2017 John Wiley & Sons Australia, Ltd.

  14. The effect of technogenic emissions on the heavy metals accumulation by herbaceous plants.

    PubMed

    Chaplygin, Victor; Minkina, Tatiana; Mandzhieva, Saglara; Burachevskaya, Marina; Sushkova, Svetlana; Poluektov, Evgeniy; Antonenko, Elena; Kumacheva, Valentina

    2018-02-07

    The effect of technogenic emissions on the input of Pb, Zn, Cd, Cu, Mn, Cr, and Ni into plants from the Poaceae and Asteraceae families has been studied. Soil and plant contamination by anthropogenic emissions from industrial enterprises leads the decreasing of crop quality; therefore, the monitoring investigation of plants and soils acquires special importance. The herbaceous plants may be used as bioindicators for main environmental changes. It was found that the high level of anthropogenic load related to atmospheric emissions from the power plant favors the heavy metal (HM) accumulation in herbaceous plants. Contamination with Pb, Cd, Cr, and Ni was revealed in plants growing near the power plant. Heavy metals arrive to plants from the soil in the form of mobile compounds. Plant family is one of the main factors affecting the HM distribution in the above- and underground parts of plants. Plants from the Poaceae family accumulate less chemical elements in their aboveground parts than the Asteraceae plants. Ambrosia artemisiifolia and Artemisia austriaca are HM accumulators. For assessing the stability of plants under contamination with HMs, metal accumulation by plants from soil (the bioconcentration factor) and metal phytoavailability from plants above- and underground parts (the acropetal coefficient) were calculated. According to the bioconcentration factor and translocation factor values, Poaceae species are most resistant to technogenic contamination with HMs. The translocation factor highest values were found for Tanacetum vulgare; the lowest bioconcentration factor values were typical for Poa pratensis.

  15. Methodical principles of recognition different source types in an acoustic-emission testing of metal objects

    NASA Astrophysics Data System (ADS)

    Bobrov, A. L.

    2017-08-01

    This paper presents issues of identification of various AE sources in order to increase the information value of AE method. This task is especially relevant for complex objects, when factors that affect an acoustic path on an object of testing significantly affect parameters of signals recorded by sensor. Correlation criteria, sensitive to type of AE source in metal objects is determined in the article.

  16. Identifying the factors affecting bike-sharing usage and degree of satisfaction in Ningbo, China

    PubMed Central

    Guo, Yanyong; Zhou, Jibiao; Wu, Yao; Li, Zhibin

    2017-01-01

    The boom in bike-sharing is receiving growing attention as societies become more aware of the importance of active non-motorized traffic modes. However, the low usage of this transport mode in China raises concerns. The primary objective of this study is to explore factors affecting bike-sharing usage and satisfaction degree of bike-sharing among the bike-sharing user population in China. Data were collected by a questionnaire survey in Ningbo. A bivariate ordered probit (BOP) model was developed to examine simultaneously those factors associated with both bike-sharing usage and satisfaction degree of bike-sharing among users. Marginal effects for contributory factors were calculated to quantify their impacts on the outcomes. The results showed that the BOP model can account for commonly shared unobserved characteristics within usage and satisfaction of bike-sharing. The BOP model results showed that the usage of bike-sharing was affected by gender, household bicycle/e-bike ownership, trip model, travel time, bike-sharing stations location, and users’ perception of bike-sharing. The satisfaction degree of bike-sharing was affected by household income, bike-sharing stations location, and users’ perception of bike-sharing. It is also found that bike-sharing usage and satisfaction degree are strongly correlated and positive in direction. The results can enhance our comprehension of the factors that affect usage and satisfaction degree of bike-sharing. Based on the results, some suggestions regarding planning, engineering, and public advocacy were discussed to increase the usage of bike-sharing in Ningbo, China. PMID:28934321

  17. Calcium-independent metal-ion catalytic mechanism of anthrax edema factor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Yuequan; Zhukovskaya, Natalia L.; Guo, Qing

    2009-11-18

    Edema factor (EF), a key anthrax exotoxin, has an anthrax protective antigen-binding domain (PABD) and a calmodulin (CaM)-activated adenylyl cyclase domain. Here, we report the crystal structures of CaM-bound EF, revealing the architecture of EF PABD. CaM has N- and C-terminal domains and each domain can bind two calcium ions. Calcium binding induces the conformational change of CaM from closed to open. Structures of the EF-CaM complex show how EF locks the N-terminal domain of CaM into a closed conformation regardless of its calcium-loading state. This represents a mechanism of how CaM effector alters the calcium affinity of CaM andmore » uncouples the conformational change of CaM from calcium loading. Furthermore, structures of EF-CaM complexed with nucleotides show that EF uses two-metal-ion catalysis, a prevalent mechanism in DNA and RNA polymerases. A histidine (H351) further facilitates the catalysis of EF by activating a water to deprotonate 3'OH of ATP. Mammalian adenylyl cyclases share no structural similarity with EF and they also use two-metal-ion catalysis, suggesting the catalytic mechanism-driven convergent evolution of two structurally diverse adenylyl cyclases.« less

  18. Identification of Risk Factors Affecting Impaired Fasting Glucose and Diabetes in Adult Patients from Northeast China

    PubMed Central

    Yin, Yutian; Han, Weiqing; Wang, Yuhan; Zhang, Yue; Wu, Shili; Zhang, Huiping; Jiang, Lingling; Wang, Rui; Zhang, Peng; Yu, Yaqin; Li, Bo

    2015-01-01

    Background: Besides genetic factors, the occurrence of diabetes is influenced by lifestyles and environmental factors as well as trace elements in diet materials. Subjects with impaired fasting glucose (IFG) have an increased risk of developing diabetes mellitus (DM). This study aimed to explore risk factors affecting IFG and diabetes in patients from Northeast China. Methods: A population-based, cross-sectional survey of chronic diseases and related risk factors was conducted in Jilin Province of Northeast China. All adult residents, aged 18–79, were invited to participate in this survey using the method of multistage stratified random cluster sampling. One hundred thirty-four patients with IFG or DM and 391 healthy control subjects were recruited. We compared demographic factors, body size measurements, healthy-related behaviors, and hair metallic element contents between IFG/diabetes patients and healthy individuals. Results: IFG/diabetes patients had a greater weight, waist, hip, and body mass index (BMI) than control subjects. Significant differences in the content of zinc (Zn), potassium (K), copper (Ca), and sodium (Na) as well as Cu/Zn ratios between IFG or DM patients and control subjects (p < 0.05) were also observed. Hair Cu, selenium (Se), and Na contents were positively correlated with blood glucose levels (Cu: rs = 0.135, p = 0.002; Se: rs = 0.110, p = 0.012; Na: rs = 0.091, p = 0.038). Polytomous logistic regression adjusting for age, sex, family history of diabetes and BMI, showed that subjects with high BMI were more likely to develop IFG and DM (IFG: OR = 1.15, OR 95% CI = 1.02–1.29; DM: OR = 1.15, OR 95% CI = 1.01–1.33). Moreover, rarely or never eating fruits was a risk factor for DM (OR = 5.46, OR 95% CI = 1.87–15.98) but not for IFG (OR = 1.70, OR 95% CI = 0.72–4.02). Subjects with abdominal obesity or DM history were more susceptible to DM (abdominal obesity: OR = 2.99, OR 95% CI = 1.07–8.37; DM history: OR = 2.69, OR 95% CI = 1

  19. Binding intensity and metal partitioning in soils affected by mining and smelting activities in Minas Gerais, Brazil.

    PubMed

    Lopes, G; Costa, E T S; Penido, E S; Sparks, D L; Guilherme, L R G

    2015-09-01

    Mining and smelting activities are potential sources of heavy metal contamination, which pose a threat to human health and ecological systems. This study investigated single and sequential extractions of Zn, Pb, and Cd in Brazilian soils affected by mining and smelting activities. Soils from a Zn mining area (soils A, B, C, D, E, and the control soil) and a tailing from a smelting area were collected in Minas Gerais state, Brazil. The samples were subjected to single (using Mehlich I solution) and sequential extractions. The risk assessment code (RAC), the redistribution index (U ts ), and the reduced partition index (I R ) have been applied to the sequential extraction data. Zinc and Cd, in soil samples from the mining area, were found mainly associated with carbonate forms. This same pattern did not occur for Pb. Moreover, the Fe-Mn oxides and residual fractions had important contributions for Zn and Pb in those soils. For the tailing, more than 70 % of Zn and Cd were released in the exchangeable fraction, showing a much higher mobility and availability of these metals at this site, which was also supported by results of RAC and I R . These differences in terms of mobility might be due to different chemical forms of the metals in the two sites, which are attributable to natural occurrence as well as ore processing.

  20. [Factors affecting the vegetation restoration after fires in cold temperate wetlands: A review].

    PubMed

    Zhao, Feng-Jun; Wang, Li-Zhong; Shu, Li-Fu; Chen, Peng-Yu; Chen, Li-guang

    2013-03-01

    Cold temperate wetland plays an important role in maintaining regional ecological balance. Fire is an important disturbance factor in wetland ecosystem. Severe burning can induce the marked degradation of the ecological functions of wetland ecosystem. The vegetation restoration, especially the early vegetation restoration, after fires, is the premise and basis for the recovery of the ecological functions of the ecosystem. This paper reviewed the research progress on the factors affecting the vegetation restoration after fires in wetlands. The vegetation restoration after fires in cold temperate wetlands was controlled by the fire intensity, fire size, vegetation types before fires, regeneration characteristics of plant species, and site conditions. It was considered that the long-term monitoring on the post-fire vegetation restoration in cold temperate wetland, the key factors affecting the vegetation restoration, the roles of frozen soil layer on the post-fire vegetation restoration, and the theories and technologies on the vegetation restoration would be the main research directions in the future.

  1. Factors affecting the sustainability of solid waste management system-the case of Palestine.

    PubMed

    Al-Khateeb, Ammar J; Al-Sari, Majed I; Al-Khatib, Issam A; Anayah, Fathi

    2017-02-01

    Understanding the predictors of sustainability in solid waste management (SWM) systems can significantly contribute to eliminate many waste management problems. In this paper, the sustainability elements of SWM systems of interest are (1) attitudes toward separation at the source, (2) behaviour regarding reuse and/or recycling and (3) willingness to pay for an improved service of SWM. The predictors affecting these three elements were studied in two Palestinian cities: Ramallah and Jericho. The data were collected via structured questionnaires and direct interviews with the respondents, and the analysis utilized a logistic regression model. The results showed that the place of residence and dwelling premises are the significant factors influencing attitudes toward separation at the source; the place of residence and age are the significant factors explaining behaviour regarding reuse and/or recycling; while the dwelling premises, gender, level of education and being received education on waste management are the significant factors affecting willingness to pay for an improved service of SWM.

  2. Factors that affect the flow of patients through triage.

    PubMed

    Lyons, Melinda; Brown, Ruth; Wears, Robert

    2007-02-01

    To use observational methods to objectively evaluate the organisation of triage and what issues may affect the effectiveness of the process. A two-phase study comprising observation of 16 h of triage in a London hospital emergency department and interviews with the triage staff to build a qualitative task analysis and study protocol for phase 2; observation and timing in triage for 1870 min including 257 patients and for 16 different members of the triage staff. No significant difference was found between grades of staff for the average triage time or the fraction of time absent from triage. In all, 67% of the time spent absent from triage was due to escorting patients into the department. The average time a patient waited in the reception before triage was 13 min 34 s; the average length of time to triage for a patient was 4 min 17 s. A significant increase in triage time was found when patients were triaged to a specialty, expected by a specialty, or were actively "seen and treated" in triage. Protocols to prioritise patients with potentially serious conditions to the front of the queue had a significantly positive effect on their waiting time. Supplementary tasks and distractions had varying effects on the timely assessment and triage of patients. The human factors method is applicable to the triage process and can identify key factors that affect the throughput at triage. Referring a patient to a specialty at triage affects significantly the triage workload; hence, alternative methods or management should be suggested. The decision to offer active treatment at triage increases the time taken, and should be based on clinical criteria and the workload determined by staffing levels. The proportion of time absent from triage could be markedly improved by support from porters or other non-qualified staff, as well as by proceduralised handovers from triage to the main clinical area. Triage productivity could be improved by all staff by becoming aware of the effect of

  3. Internal and external environmental factors affecting the performance of hospital-based home nursing care.

    PubMed

    Noh, J-W; Kwon, Y-D; Yoon, S-J; Hwang, J-I

    2011-06-01

    Numerous studies on HNC services have been carried out by signifying their needs, efficiency and effectiveness. However, no study has ever been performed to determine the critical factors associated with HNC's positive results despite the deluge of positive studies on the service. This study included all of the 89 training hospitals that were practising HNC service in Korea as of November 2006. The input factors affecting the performance were classified as either internal or external environmental factors. This analysis was conducted to understand the impact that the corresponding factors had on performance. Data were analysed by using multiple linear regressions. The internal and external environment variables affected the performance of HNC based on univariate analysis. The meaningful variables were internal environmental factors. Specifically, managerial resource (the number of operating beds and the outpatient/inpatient ratio) were meaningful when the multiple linear regression analysis was performed. Indeed, the importance of organizational culture (the passion of HNC nurses) was significant. This study, considering the limited market size of Korea, illustrates that the critical factor for the development of hospital-led HNC lies with internal environmental factors rather than external ones. Among the internal environmental factors, the hospitals' managerial resource-related factors (specifically, the passion of nurses) were the most important contributing element. © 2011 The Authors. International Nursing Review © 2011 International Council of Nurses.

  4. An Investigation of Relationships between Internal and External Factors Affecting Technology Integration in Classrooms

    ERIC Educational Resources Information Center

    Hur, Jung Won; Shannon, David; Wolf, Sara

    2016-01-01

    Various factors affecting technology integration have been identified, but little research has examined the relationships between factors, especially internal and external ones, and whether they directly or indirectly influenced each other. To fill this research gap, this study examined the significance and relationships of five factors…

  5. Do soft drinks affect metal ions release from orthodontic appliances?

    PubMed

    Mikulewicz, Marcin; Wołowiec, Paulina; Loster, Bartłomiej W; Chojnacka, Katarzyna

    2015-01-01

    The effect of orange juice and Coca Cola(®) on the release of metal ions from fixed orthodontic appliances. A continuous flow system designed for in vitro testing of orthodontic appliances was used. Orange juice/Coca Cola(®) was flowing through the system alternately with artificial saliva for 5.5 and 18.5h, respectively. The collected samples underwent a multielemental ICP-OES analysis in order to determine the metal ions release pattern in time. The total mass of ions released from the appliance into orange juice and Coca Cola(®) (respectively) during the experiment was calculated (μg): Ni (15.33; 37.75), Cr (3.604; 1.052), Fe (48.42; ≥ 156.1), Cu (57.87, 32.91), Mn (9.164; 41.16), Mo (9.999; 30.12), and Cd (0.5967; 2.173). It was found that orange juice did not intensify the release of metal ions from orthodontic appliances, whereas Coca Cola(®) caused increased release of Ni ions. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. FACTORS AFFECTING SUSCEPTIBILITY OF THE CORAL MONTASTRAEA FAVEOLATE TO BLACK-BAND DISEASE

    EPA Science Inventory

    Black-band disease affects many species of tropical reef-building corals, but it is unclear what factors contribute to the disease-susceptibility of individual corals or how the disease is transmitted between colonies. Studies have suggested that the ability of black-band disease...

  7. Commentary on factors affecting transverse vibration using an idealized theoretical equation

    Treesearch

    Joseph F. Murphy

    2000-01-01

    An idealized theoretical equation to calculate flexural stiffness using transverse vibration of a simply end-supported beam is being considered by the American Society of Testing and Materials (ASTM) Wood Committee D07 to determine lumber modulus of elasticity. This commentary provides the user a quantitative view of six factors that affect the accuracy of using the...

  8. Factors Affecting the Identification of Research Problems in Educational Administration Studies

    ERIC Educational Resources Information Center

    Yalçin, Mikail; Bektas, Fatih; Öztekin, Özge; Karadag, Engin

    2016-01-01

    The purpose of this study is to reveal the factors that affect the identification of research problems in educational administration studies. The study was designed using the case study method. Criterion sampling was used to determine the work group; the criterion used to select the participants was that of having a study in the field of…

  9. System-Level Evaluation: Language and Other Background Factors Affecting Mathematics Achievement

    ERIC Educational Resources Information Center

    Howie, Sarah

    2005-01-01

    The aim of this study is to describe and to explore the main factors affecting the performance of South African pupils in the mathematics test of the Third International Mathematics and Science Study-Repeat (TIMSS-R). The first objective was to describe the performance of the pupils in the mathematics test, the pupils' proficiency in English, as…

  10. Factors affecting physicians' responses to patients' requests for antidepressants: focus group study.

    PubMed

    Tentler, Aleksey; Silberman, Jordan; Paterniti, Debora A; Kravitz, Richard L; Epstein, Ronald M

    2008-01-01

    The ways in which patients' requests for antidepressants affect physicians' prescribing behavior are poorly understood. To describe physicians' affective and cognitive responses to standardized patients' (SPs) requests for antidepressants, as well as the attitudinal and contextual factors influencing prescribing behavior. Focus group interviews and brief demographic questionnaires. Twenty-two primary care physicians in 6 focus groups; all had participated in a prior RCT of the influence of patients' requests on physicians' prescribing. Iterative review of interview transcripts, involving qualitative coding and thematic analysis. Physicians participating in the focus groups were frequently unaware of and denied the degree to which their thinking was biased by patient requests, but were able to recognize such biases after facilitated reflection. Common affective responses included annoyance and empathy. Common cognitive reactions resulted in further diagnostic inquiry or in acquiescing to the patient's demands to save time or build the patient-clinician relationship. Patients' requests for medication prompted the participants to err on the side of overtreating versus careful review of clinical indications. Lack of time and participants' attitudes--toward the role of the patient and the pharmaceutical ads--also influenced their responses, prompting them to interpret patient requests as diagnostic clues or opportunities for efficiency. This study provides a taxonomy of affective and cognitive responses to patients' requests for medications and the underlying attitudes and contextual factors influencing them. Improved capacity for moment-to-moment self-awareness during clinical reasoning processes may increase the appropriateness of prescribing.

  11. Patient and disease factors affecting the choice and adherence to active surveillance.

    PubMed

    Dall'Era, Marc A

    2015-05-01

    Treatment decisions for low-risk prostate cancer are arguably some of the most challenging in oncology. Active surveillance has emerged as an important option for many men with tumors estimated to have a low metastatic potential. Multiple complex patient and physician factors affect the recommendation, selection, and adherence to active surveillance. While baseline clinical criteria are used to identify candidates for this approach, it is important to identify and understand other forces that may influence the management of prostate cancer with active surveillance. Patient perceptions and acceptance of active surveillance have improved over time. Treatment decisions for prostate cancer are strongly associated with physician recommendations, and a high-quality relationship between the patient and his healthcare system is critical to successful active surveillance. Patient understanding of prostate cancer and consistency of information received from separate physicians can affect a decision to pursue active surveillance. Psychological symptoms, most notably regarding anxiety and distress, can affect adherence to active surveillance over time. In general, anxiety for men on active surveillance is low, and lifestyle interventions and self-management strategies may be helpful for increasing quality of life and limiting abandonment of active surveillance in the absence of disease progression. Multiple factors may affect the decision for and adherence to active surveillance for prostate cancer. It is important for both physicians and patients to be aware of these issues and work towards individualized approaches and interventions as needed to increase adoption of active surveillance in the future.

  12. Turkish nurses' assessments of their power and the factors that affect it.

    PubMed

    Basaran, Seher; Duygulu, Sergul

    2015-11-01

    To explore nurses' self-assessments of power and their opinions regarding factors affecting power in Turkey using a cross-sectional, descriptive study. In order to safely and cost-effectively care for patients, nurses must perceive themselves as powerful and have the use and control of power resources. The study sample consisted of 297 nurses in six hospitals: two government hospitals, two university hospitals and two private hospitals. Data were collected using the Demographic Data Form and Power Question Form. Nurses regarded themselves as 'quite powerful' regarding persuasion (53.2%) and referent power (43.4%). Many nurses also regarded themselves as having positional power and 'quite powerful' regarding, reward (44.1%) and legitimate power (34.7%). Nurses saw themselves as least powerful in resource power (48.1%). Individual, educational and organisational factors were the main factors affecting personal and positional power sources. Turkish nurses regarded themselves as above average on being powerful in both the personal and positional power base but not in resource power. We recommend that nurses, educators and managers develop strategies to support nurses' power as a way to enhance the patient care outcomes. © 2014 John Wiley & Sons Ltd.

  13. Factors affecting economies of scale in combined sewer systems.

    PubMed

    Maurer, Max; Wolfram, Martin; Anja, Herlyn

    2010-01-01

    A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.

  14. Metal sulfide initiators for metal oxide sorbent regeneration

    DOEpatents

    Turk, Brian S.; Gupta, Raghubir P.

    2001-01-01

    A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing gas. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream.

  15. Metal sulfide initiators for metal oxide sorbent regeneration

    DOEpatents

    Turk, Brian S.; Gupta, Raghubir P.

    1999-01-01

    A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream.

  16. Metal sulfide initiators for metal oxide sorbent regeneration

    DOEpatents

    Turk, B.S.; Gupta, R.P.

    1999-06-22

    A process of regenerating a sulfided sorbent is provided. According to the process of the invention, a substantial portion of the energy necessary to initiate the regeneration reaction is provided by the combustion of a particulate metal sulfide additive. In using the particulate metal sulfide additive, the oxygen-containing gas used to regenerate the sulfided sorbent can be fed to the regeneration zone without heating or at a lower temperature than used in conventional processes wherein the regeneration reaction is initiated only by heating the oxygen-containing gas. The particulate metal sulfide additive is preferably an inexpensive mineral ore such as iron pyrite which does not adversely affect the regeneration or corresponding desulfurization reactions. The invention further includes a sorbent composition comprising the particulate metal sulfide additive in admixture with an active metal oxide sorbent capable of removing one or more sulfur compounds from a sulfur-containing gas stream. 1 fig.

  17. Albumin as marker for susceptibility to metal ions in metal-on-metal hip prosthesis patients.

    PubMed

    Facchin, F; Catalani, S; Bianconi, E; Pasquale, D De; Stea, S; Toni, A; Canaider, S; Beraudi, A

    2017-04-01

    Metal-on-metal (MoM) hip prostheses are known to release chromium and cobalt (Co), which negatively affect the health status, leading to prosthesis explant. Albumin (ALB) is the main serum protein-binding divalent transition metals. Its binding capacity can be affected by gene mutations or modification of the protein N-terminal region, giving the ischaemia-modified albumin (IMA). This study evaluated ALB, at gene and protein level, as marker of individual susceptibility to Co in MoM patients, to understand whether it could be responsible for the different management of this ion. Co was measured in whole blood, serum and urine of 40 MoM patients. A mutational screening of ALB was performed to detect links between mutations and metal binding. Finally, serum concentration of total ALB and IMA were measured. Serum total ALB concentration was in the normal range for all patients. None of the subjects presented mutations in the investigated gene. Whole blood, serum and urine Co did not correlate with serum total ALB or IMA, although IMA was above the normal limit in most subjects. The individual susceptibility is very important for patients' health status. Despite the limited results of this study, we provide indications on possible future investigations on the toxicological response to Co.

  18. The role of ions, heavy metals, fluoride, and agrochemicals: critical evaluation of potential aetiological factors of chronic kidney disease of multifactorial origin (CKDmfo/CKDu) and recommendations for its eradication.

    PubMed

    Wimalawansa, Sunil J

    2016-06-01

    The pollution of water and food through human waste and anthropogenic activities, including industrial waste and agricultural runoff, is a mounting problem worldwide. Water pollution from microbes causes identifiable diarrhoeal illnesses. The consumption of water contaminated with heavy metals, fluoride, and other toxins causes insidious illnesses that lead to protracted, non-communicable diseases and death. Chronic kidney disease of unusual/uncertain/unknown aetiology is one such example, began to manifest in the mid-1960s in several dry-zonal agricultural societies in developing economies that are located around the equator. In Sri Lanka, such a disease is affecting the North Central Province, the rice bowl of the country that first appeared in the mid-1990s. Several potential causes have been postulated, including heavy metals, fluoride, cyanobacterial and algae toxins, agrochemicals, and high salinity and ionicity in water, but no specific source or causative factor has been identified for CKD of multifactorial origin (CKDmfo). Three large studies conducted in the recent past failed to find any of the postulated components (heavy metals, cyanobacterial toxins, fluoride, salinity, or agrochemicals) at levels higher than those deemed safe by the World Health Organization and the US Environmental Protection Agency. At the reported low levels in water and with the heterogeneous geographical distribution, it is unrealistic to expect any of these components individually could cause this disease. However, the additive or synergistic effects of a combination of factors and components, even at lower exposure levels, together with malnutrition and harmful behaviours, and/or a yet-unidentified (or not investigated) toxin, can cause this epidemic. Because the cause is unknown, scientists need to work on broader hypotheses, so that key causative elements are not missed. Taken together the plausibility of multiple factors in the genesis of this disease, the appropriate

  19. Bioconcentration factors and potential human health risks of heavy metals in cultivated Lentinus edodes in Chengdu, People's Republic of China.

    PubMed

    Pei, Donghui; Xie, Han; Song, Haihai; Xu, Heng; Wu, Yumeng

    2015-02-01

    Lentinus edodes is one of the most popular edible mushrooms in the market. However, it contains heavy metals that are poisonous to humans even at trace concentrations. The concentrations and bioconcentration factors of five heavy metals in cultivated L. edodes in Chengdu were studied, and the potential health risks to local residents associated with the cultivated L. edodes consumption were evaluated. Total concentrations of cadmium (Cd), lead (Pb), chromium (Cr), arsenic (As), and mercury were determined in the fruiting bodies and the substrate from three agricultural areas. Fruiting bodies samples were collected at different growing times (2, 4, 6, and 8 days). The bioconcentration factors of heavy metals from the substrate to the fruiting bodies were estimated, and the potential health risks of local L. edodes were assessed. Because antioxidant enzymes can resist the creation of reactive oxygen species and defend against heavy metals, the activities of three antioxidant enzymes (superoxide dismutase, catalase, and peroxidase) in the fruiting bodies were also determined. A gradual change in heavy metal concentrations occurred across the growing time of the fruiting bodies. Cd transferred from the substrate to the fruiting bodies in larger concentrations than did Pb, Cr, and As. However, Chengdu residents were not exposed to significant health risks associated with consumption of local L. edodes. Nevertheless, more attention should be focused on children because of their higher sensitivity to metal pollutants.

  20. Maternal and Neonatal Birth Factors Affecting the Age of ASD Diagnosis.

    PubMed

    Darcy-Mahoney, Ashley; Minter, Bonnie; Higgins, Melinda; Guo, Ying; Zauche, Lauren Head; Hirst, Jessica

    2016-12-01

    Early diagnosis of autism spectrum disorders (ASD) enables early intervention that improves long term functioning of children with ASD but is often delayed until age of school entry. Few studies have identified factors that affect timely diagnosis. This study addressed how maternal education, race, age, marital status as well as neonatal birth factors affect the age at which a child is diagnosed with ASD. This study involved a retrospective analysis of 664 records of children treated at one of the largest autism treatment centers in the United States from March 1, 2009 to December 30, 2010. Logistic regression and Cox proportional hazards regression were used to identify maternal and neonatal factors associated with age of diagnosis. Infant gender, maternal race, marital status, and maternal age were identified as significant factors for predicting the age of ASD diagnosis. In the Cox proportional hazards regression model, only maternal race and marital status were included. Median survival age till diagnosis of children born to married mothers was 53.4 months compared to 57.8 months and 63.7 months of children born to single and divorced or widowed mothers respectively. Median survival age till diagnosis for children of African American mothers was 53.8 months compared to 57.2 months for children of Caucasian mothers. No statistically significant difference of timing of ASD diagnosis was found for children of varying gestational age. Children born to older or married mothers and mothers of minority races were more likely to have an earlier ASD diagnosis. No statistically significant differences in timing of ASD diagnosis were found for children born at varying gestational ages. Identification of these factors has the potential to inform public health outreach aimed at promoting timely ASD diagnosis. This work could enhance clinical practice for timelier diagnoses of ASD by supporting parents and clinicians around the world in identifying risk factors beyond gender

  1. Factors affecting injury severity of vehicle occupants following road traffic collisions.

    PubMed

    Abu-Zidan, Fikri M; Eid, Hani O

    2015-01-01

    We aimed to define factors affecting injury severity of vehicle occupants following road traffic collisions (RTC). 422 vehicle occupants (343 males, 81.3%) with RTC-related injuries were prospectively studied over 18 months. General linear model was used to test the effect of age, gender, alcohol and drug use, time of injury, mechanism of injury, size and speed of the vehicle, position in the vehicle, seatbelt usage, and air bag deployment on the Injury Severity Score (ISS) of the vehicle occupants. The mean (range) age of patients was 28.2 (1-78) years and the mean (range) ISS was 7.9 (1-50). Front impact was the most common mechanism of injury (32.9%) followed by rollover (25.6%) and side impact (22.3%). 18.2% used seatbelts. The general linear model was highly significant and showed that mechanism of injury (p<0.0001), speed of the vehicle (p=0.02), and age of the vehicle occupant (p=0.03) significantly affected the Injury Severity Score. The mechanism of the RTC, the vehicle speed, and age of the vehicle occupant are the most important factors affecting the severity of road traffic collision injuries. A detailed history of the mechanism of injury is important for alerting clinicians to severity of injury, the need for admission, and workup of the patients. Furthermore, strict speed limit enforcement is an injury prevention priority in our community. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Factors affecting frequency and orbit utilization by high power transmission satellite systems.

    NASA Technical Reports Server (NTRS)

    Kuhns, P. W.; Miller, E. F.; O'Malley, T. A.

    1972-01-01

    The factors affecting the sharing of the geostationary orbit by high power (primarily television) satellite systems having the same or adjacent coverage areas and by satellites occupying the same orbit segment are examined and examples using the results of computer computations are given. The factors considered include: required protection ratio, receiver antenna patterns, relative transmitter power, transmitter antenna patterns, satellite grouping, and coverage pattern overlap. The results presented indicate the limits of system characteristics and orbit deployment which can result from mixing systems.

  3. Factors affecting frequency and orbit utilization by high power transmission satellite systems

    NASA Technical Reports Server (NTRS)

    Kuhns, P. W.; Miller, E. F.; Malley, T. A.

    1972-01-01

    The factors affecting the sharing of the geostationary orbit by high power (primarily television) satellite systems having the same or adjacent coverage areas and by satellites occupying the same orbit segment are examined and examples using the results of computer computations are given. The factors considered include: required protection ratio, receiver antenna patterns, relative transmitter power, transmitter antenna patterns, satellite grouping, and coverage pattern overlap. The results presented indicated the limits of system characteristics and orbit deployment which can result from mixing systems.

  4. Analysis of Factors that Affect the Teacher Certification Exam Results in a University System in Puerto Rico

    ERIC Educational Resources Information Center

    Garofalo, Jorge H.

    2009-01-01

    The purpose of this study was to analyze the factors that affect a teacher preparation exam results within a University System in Puerto Rico. Using Bertalanffy's System Theory as theoretical framework, this mixed methods study examined factors in the university system that could have affected student's preparation for a teacher exam (PCMAS by its…

  5. Does heavy metal exposure affect the condition of Whitethroat (Sylvia communis) nestlings?

    PubMed

    Turzańska-Pietras, Katarzyna; Chachulska, Justyna; Polechońska, Ludmiła; Borowiec, Marta

    2018-03-01

    Anthropogenic pollution results in high concentrations of heavy metals in the environment. Due to their persistence and a high potential for bioaccumulation, metals are a real threat for birds breeding in industrial areas. The aim of the present study has been to explore the contents of heavy metals (arsenic As, cadmium Cd, chromium Cr, copper Cu, iron Fe, nickel Ni, lead Pb and zinc Zn) in the excreta of Whitethroat (Sylvia communis) nestlings living in polluted environment and to investigate the relationship between these contents and the nestlings' condition. Excrement samples contained all the studied elements. The contents of arsenic, cadmium, copper and zinc in the excreta of nestlings from nests located close to a slag dump were several times higher than in the soil near the dump, which suggested accumulation in food consumed by the birds. Condition parameters (body mass and haemoglobin concentration) were not related to heavy metal concentrations in the nestlings' excreta, except of Zn. It is possible that Whitethroats are able to detoxicate heavy metals to a certain extent. Detailed, multi-element analysis of the environment, food and bird tissues or excreta should be performed to explore relations between different chemicals and bird condition.

  6. Molecular gas in low-metallicity starburst galaxies:. Scaling relations and the CO-to-H2 conversion factor

    NASA Astrophysics Data System (ADS)

    Amorín, R.; Muñoz-Tuñón, C.; Aguerri, J. A. L.; Planesas, P.

    2016-04-01

    Context. Tracing the molecular gas-phase in low-mass star-forming galaxies becomes extremely challenging due to significant UV photo-dissociation of CO molecules in their low-dust, low-metallicity ISM environments. Aims: We aim to study the molecular content and the star-formation efficiency of a representative sample of 21 blue compact dwarf galaxies (BCDs), previously characterized on the basis of their spectrophotometric properties. Methods: We present CO (1-0) and (2-1) observations conducted at the IRAM-30m telescope. These data are further supplemented with additional CO measurements and multiwavelength ancillary data from the literature. We explore correlations between the derived CO luminosities and several galaxy-averaged properties. Results: We detect CO emission in seven out of ten BCDs observed. For two galaxies these are the first CO detections reported so far. We find the molecular content traced by CO to be correlated with the stellar and Hi masses, star formation rate (SFR) tracers, the projected size of the starburst, and its gas-phase metallicity. BCDs appear to be systematically offset from the Schmidt-Kennicutt (SK) law, showing lower average gas surface densities for a given ΣSFR, and therefore showing extremely low (≲0.1 Gyr) H2 and H2 +Hi depletion timescales. The departure from the SK law is smaller when considering H2 +Hi rather than H2 only, and is larger for BCDs with lower metallicity and higher specific SFR. Thus, the molecular fraction (ΣH2/ ΣHI) and CO depletion timescale (ΣH2/ ΣSFR) of BCDs is found to be strongly correlated with metallicity. Using this, and assuming that the empirical correlation found between the specific SFR and galaxy-averaged H2 depletion timescale of more metal-rich galaxies extends to lower masses, we derive a metallicity-dependent CO-to-H2 conversion factor αCO,Z ∝ (Z/Z⊙)- y, with y = 1.5(±0.3)in qualitative agreement with previous determinations, dust-based measurements, and recent model

  7. Factors Affecting the Full Use of Library and Information Management Systems by Library Personnel

    ERIC Educational Resources Information Center

    Skretas, Georgios

    2005-01-01

    Purpose: To provide a general list of factors that affects and determines the full use of library information management systems (LIMS) by library staff. Design/methodology/approach: The factors, which were identified mainly during participation in the implementation of automation projects in Greece, are listed and briefly analysed in categories…

  8. Resolution V fractional factorial design for screening of factors affecting weakly basic drugs liposomal systems.

    PubMed

    Nageeb El-Helaly, Sara; Habib, Basant A; Abd El-Rahman, Mohamed K

    2018-07-01

    This study aims to investigate factors affecting weakly basic drugs liposomal systems. Resolution V fractional factorial design (2 V 5-1 ) is used as an example of screening designs that would better be used as a wise step before proceeding with detailed factors effects or optimization studies. Five factors probable to affect liposomal systems of weakly basic drugs were investigated using Amisulpride as a model drug. Factors studied were; A: Preparation technique B: Phosphatidyl choline (PhC) amount (mg) C: Cholesterol: PhC molar ratio, D: Hydration volume (ml) and E: Sonication type. Levels investigated were; Ammonium sulphate-pH gradient technique or Transmembrane zinc chelation-pH gradient technique, 200 or 400 mg, 0 or 0.5, 10 or 20 ml and bath or probe sonication for A, B, C, D and E respectively. Responses measured were Particle size (PS) (nm), Zeta potential (ZP) (mV) and Entrapment efficiency percent (EE%). Ion selective electrode was used as a novel method for measuring unentrapped drug concentration and calculating entrapment efficiency without the need for liposomal separation. Factors mainly affecting the studied responses were Cholesterol: PhC ratio and hydration volume for PS, preparation technique for ZP and preparation technique and hydration volume for EE%. The applied 2 V 5-1 design enabled the use of only 16 trial combinations for screening the influence of five factors on weakly basic drugs liposomal systems. This clarifies the value of the use of screening experiments before extensive investigation of certain factors in detailed optimization studies. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Study of factors affecting the appearance of colors under microscopes

    NASA Astrophysics Data System (ADS)

    Zakizadeh, Roshanak; Martinez-Garcia, Juan; Raja, Kiran B.; Siakidis, Christos

    2013-11-01

    The variation of colors in microscopy systems can be quite critical for some users. To address this problem, a study is conducted to analyze how different factors such as size of the sample, intensity of the microscope's light source and the characteristics of the material like chroma and saturation can affect the color appearance through the eyepiece of the microscope. To study the changes in colors considering these factors, the spectral reflectance of 24 colors of GretagMacbeth Classic ColorChecker® and Mini ColorChecker® which are placed under a Nikon ECLIPSE MA200 microscope®2 using dark filed and bright field illuminations which result in different intensity levels, is measured using a spectroradiometer®3 which was placed in front of the eyepiece of the microscope. The results are compared with the original data from N. Ohta1. The evaluation is done by observing the shift in colors in the CIE 1931 Chromaticity Diagram and the CIELAB space, also by applying a wide set of color-difference formulas, namely: CIELAB, CMC, BFD, CIE94, CIEDE2000, DIN99d and DIN99b. Furthermore, to emphasize on the color regions in which the highest difference is observed, the authors have obtained the results from another microscope; Olympus SZX10®4, which in this case the measurement is done by mounting the spectroradiometer to the camera port of the microscope. The experiment leads to some interesting results, among which is the consistency in the highest difference observed considering different factors or how the change in saturation of the samples of the same hue can affect the results.

  10. Comparative assessment of metallurgical recovery of metals from electronic waste with special emphasis on bioleaching.

    PubMed

    Priya, Anshu; Hait, Subrata

    2017-03-01

    Waste electrical and electronic equipment (WEEE) or electronic waste (e-waste) is one of the fastest growing waste streams in the urban environment worldwide. The core component of printed circuit board (PCB) in e-waste contains a complex array of metals in rich quantity, some of which are toxic to the environment and all of which are valuable resources. Therefore, the recycling of e-waste is an important aspect not only from the point of waste treatment but also from the recovery of metals for economic growth. Conventional approaches for recovery of metals from e-waste, viz. pyrometallurgical and hydrometallurgical techniques, are rapid and efficient, but cause secondary pollution and economically unviable. Limitations of the conventional techniques have led to a shift towards biometallurgical technique involving microbiological leaching of metals from e-waste in eco-friendly manner. However, optimization of certain biotic and abiotic factors such as microbial species, pH, temperature, nutrients, and aeration rate affect the bioleaching process and can lead to profitable recovery of metals from e-waste. The present review provides a comprehensive assessment on the metallurgical techniques for recovery of metals from e-waste with special emphasis on bioleaching process and the associated factors.

  11. A holistic approach to factors affecting depression in haemodialysis patients.

    PubMed

    Gerogianni, Georgia; Kouzoupis, Anastasios; Grapsa, Eirini

    2018-05-19

    Depression in dialysis populations is affected by co-morbid diseases, such as cardiovascular disease, diabetes, and immune dysfunction, and it also includes high suicide risk and frequent hospitalizations. Depressive disorders have a close association with malnutrition and chronic inflammation, as well as with cognitive impairment. Impaired cognitive function may be manifested as low adherence to dialysis treatment, leading to malnutrition. Additionally, chronic pain and low quality of sleep lead to high rates of depressive symptoms in haemodialysis patients, while an untreated depression can cause sleep disturbances and increased mortality risk. Depression can also lead to sexual dysfunction and non-adherence, while unemployment can cause depressive disorders, due to patients' feelings of being a financial burden on their family. The present review provides a holistic approach to the factors affecting depression in haemodialysis, offering significant knowledge to renal professionals.

  12. Evaluating Heavy Metal Stress Levels in Rice Based on Remote Sensing Phenology.

    PubMed

    Liu, Tianjiao; Liu, Xiangnan; Liu, Meiling; Wu, Ling

    2018-03-14

    Heavy metal pollution of croplands is a major environmental problem worldwide. Methods for accurately and quickly monitoring heavy metal stress have important practical significance. Many studies have explored heavy metal stress in rice in relation to physiological function or physiological factors, but few studies have considered phenology, which can be sensitive to heavy metal stress. In this study, we used an integrated Normalized Difference Vegetation Index (NDVI) time-series image set to extract remote sensing phenology. A phenological indicator relatively sensitive to heavy metal stress was chosen from the obtained phenological periods and phenological parameters. The Dry Weight of Roots (WRT), which directly affected by heavy metal stress, was simulated by the World Food Study (WOFOST) model; then, a feature space based on the phenological indicator and WRT was established for monitoring heavy metal stress. The results indicated that the feature space can distinguish the heavy metal stress levels in rice, with accuracy greater than 95% for distinguishing the severe stress level. This finding provides scientific evidence for combining rice phenology and physiological characteristics in time and space, and the method is useful to monitor heavy metal stress in rice.

  13. Factors Affecting Accent Acquisition: The Case of Russian Immigrants in Israel

    ERIC Educational Resources Information Center

    Abu-Rabia, Salim; Iliyan, Salman

    2011-01-01

    A debate centers on whether the native accent is acquired early in life or whether it can be acquired at any time. This study investigated factors that may affect native accent acquisition in a second language. Participants in this study were 50 Russians who immigrated to Israel, 17 males and 33 females. Their age on arrival was 5 to 25 years.…

  14. Influence of Mode of Metal Transfer on Microstructure and Mechanical Properties of Gas Metal Arc-Welded Modified Ferritic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Mukherjee, Manidipto; Pal, Tapan Kumar

    2012-06-01

    This article describes in detail the effect of the modes of metal transfer on the microstructure and mechanical properties of gas metal arc-welded modified ferritic stainless steel (SSP 409M) sheets (as received) of 4 mm thickness. The welded joints were prepared under three modes of metal transfer, i.e., short-circuit (SC), spray (S), transfer, and mix (M) mode transfer using two different austenitic filler wires (308L and 316L) and shielding gas composition of Ar + 5 pct CO2. The welded joints were evaluated by means of microstructural, hardness, notched tensile strength, Charpy impact toughness, and high cycle fatigue. The dependence of weld metal microstructure on modes of metal transfer and filler wires has been determined by dilution calculation, WRC-1992 diagram, Creq/Nieq ratio, stacking fault energy (SFE), optical microscopy (OM), and transmission electron microscopy (TEM). It was observed that the microstructure as well as the tensile, Charpy impact, and high cycle fatigue of weld metal is significantly affected by the mode of metal transfer and filler wire used. However, the heat-affected zone (HAZ) is affected only by the modes of metal transfer. The results have been correlated with the microstructures of weld and HAZ developed under different modes of metal transfer.

  15. Factors Affecting the Identification of Hispanic English Language Learners in Special Education

    ERIC Educational Resources Information Center

    Becker, Gail I.

    2012-01-01

    This qualitative phenomenological study revealed factors affecting the overrepresentation of Hispanic English language learners (ELLs) in special education. An analysis of the lived experiences of school professionals indicate multiple causes that determine students to be disabled often in violation of state and federal guidelines. Child study…

  16. Environmental factors affecting benthic macrofauna along a gradient of intermediate sandy beaches in northern Spain

    NASA Astrophysics Data System (ADS)

    Rodil, I. F.; Lastra, M.

    2004-09-01

    Ten sandy beaches along the north coast of Spain were studied during September 1999 to analyse the number of species, abundance and biomass of macroinfauna along a gradient of intermediate beach types and exposure range. Faunal samples were collected with metallic cylinders (25 cm diameter, 15 cm depth) at 10 equally spaced shore levels along six replicated transects separated randomly and extending from above the drift line to the low tide swash zone. Exposure rate, Dean's parameter ( Ω), beach state index (BSI) and relative tidal range (RTR) were estimated at each beach. Length and width of the beach, intertidal slope, sorting and median grain size and also swash amplitude and wave characteristics were measured. The number of species was between 10 and 29. Macrofaunal abundances ranged between 4962 and 71,228 ind. linear m -1 and between 31 and 329 ind. m -2, while biomass (ash free dry weight) ranged between 0.027 and 0.278 g m -2 and between 3 and 61 g linear m -1. The results show some significant trends: the number of species is the biotic variable most affected by physical and morphodynamic factors, increasing linearly with relative tidal range and decreasing with increasing average grain size. The same trend was observed from exposed to very exposed beaches and the biomass decreased exponentially with increasing average grain size. These trends agree with previous studies in different coasts in the world where coarse sands limit the benthic macrofauna. The morphodynamic parameters as Dean's parameter or Beach State Index did not show a predictive value. The results suggest that different characteristics of benthic macrofauna communities in intermediate beaches can be affected in different ways by the physical processes involved in beach morphodynamics.

  17. Factors affecting recovery from work-related, low back disorders in autoworkers.

    PubMed

    Oleske, Denise M; Neelakantan, Janani; Andersson, Gunnar B; Hinrichs, Bradley G; Lavender, Steven A; Morrissey, Mary J; Zold-Kilbourn, Phyllis; Taylor, Emily

    2004-08-01

    To simultaneously evaluate personal, medical, and job factors that could affect recovery from work-related, low back disorders, specifically focusing on an active working sample. Observational, longitudinal study. Two US automotive plants. Employees (N=352; 289 men, 63 women; mean age +/- standard deviation, 45.1+/-7.5 y) who were active hourly autoworkers, diagnosed with work-related, low back disorder by the plant's medical department. Not applicable. Oswestry Disability Questionnaire for back pain was used to evaluate recovery. Factors associated with better recovery were lower stress levels (P<.001) and exercise or physical activity outside work (P<.001); factors associated with higher disability levels over time were current cigarette smoking (P<.01) and bedrest (P<.001). Personal modifiable factors are major influences in the recovery from work-related, low back disorders, even in active working populations. Interventions aimed at increasing exercise and decreasing stress should also be considered as a part of rehabilitation in employed persons with low levels of disability.

  18. Factors affecting access to healthcare services by intermarried Filipino women in rural Tasmania: a qualitative study.

    PubMed

    Hannah, Chona T; Lê, Quynh

    2012-10-01

    Access to health care services is vital for every migrant's health and wellbeing. However, migrants' cultural health beliefs and views can hinder their ability to access available services. This study examined factors affecting access to healthcare services for intermarried Filipino women in rural Tasmania, Australia. A qualitative approach using semi-structured interviews was employed to investigate the factors affecting access to healthcare services for 30 intermarried Filipino women in rural Tasmania. The study used grounded theory and thematic analysis for its data analysis. Nvivo v8 (www.qsrinternational.com) was also used to assist the data coding process and analysis. Five influencing factors were identified: (1) language or communication barriers; (2) area of origin in the Philippines; (3) cultural barriers; (4) length of stay in Tasmania; and (5) expectations of healthcare services before and after migration. Factors affecting intermarried Filipino women in accessing healthcare services are shaped by their socio-demographic and cultural background. The insights gained from this study are useful to health policy-makers, healthcare professionals and to intermarried female migrants. The factors identified can serve as a guide to improve healthcare access for Filipino women and other migrants.

  19. Multiple Weather Factors Affect Apparent Survival of European Passerine Birds

    PubMed Central

    Salewski, Volker; Hochachka, Wesley M.; Fiedler, Wolfgang

    2013-01-01

    Weather affects the demography of animals and thus climate change will cause local changes in demographic rates. In birds numerous studies have correlated demographic factors with weather but few of those examined variation in the impacts of weather in different seasons and, in the case of migrants, in different regions. Using capture-recapture models we correlated weather with apparent survival of seven passerine bird species with different migration strategies to assess the importance of selected facets of weather throughout the year on apparent survival. Contrary to our expectations weather experienced during the breeding season did not affect apparent survival of the target species. However, measures for winter severity were associated with apparent survival of a resident species, two short-distance/partial migrants and a long-distance migrant. Apparent survival of two short distance migrants as well as two long-distance migrants was further correlated with conditions experienced during the non-breeding season in Spain. Conditions in Africa had statistically significant but relatively minor effects on the apparent survival of the two long-distance migrants but also of a presumably short-distance migrant and a short-distance/partial migrant. In general several weather effects independently explained similar amounts of variation in apparent survival for the majority of species and single factors explained only relatively low amounts of temporal variation of apparent survival. Although the directions of the effects on apparent survival mostly met our expectations and there are clear predictions for effects of future climate we caution against simple extrapolations of present conditions to predict future population dynamics. Not only did weather explains limited amounts of variation in apparent survival, but future demographics will likely be affected by changing interspecific interactions, opposing effects of weather in different seasons, and the potential for

  20. Association Between Pseudotumor Formation and Patient Factors in Metal-on-Metal Total Hip Arthroplasty Population.

    PubMed

    Kleeman, Lindsay T; Goltz, Daniel; Seyler, Thorsten M; Mammarappallil, Joseph G; Attarian, David E; Wellman, Samuel S; Bolognesi, Michael P

    2018-07-01

    Pseudotumor formation from metal-on-metal (MoM) hip implants is associated with implant revision. The relationship between pseudotumor type and patient outcomes is unknown. We retrospectively reviewed patients with a MoM total hip arthroplasty and metal artifact reduction sequence magnetic resonance imaging. Pseudotumors were graded using a validated classification system by a fellowship-trained radiologist. Patient demographics, metal ion levels, and implant survival were analyzed. Pseudotumors were present in 49 hips (53%). Thirty-two (65%) pseudotumors were cystic thin walled, 8 (16%) were cystic thick walled, and 9 (18%) were solid masses. Patients with pseudotumors had high offset stems (P = .030) but not higher metal ion levels. Patients with thick-walled cystic or solid masses were more likely to be symptomatic (P = .025) and were at increased risk for revision (P = .004) compared to patients with cystic lesions. Pseudotumor formation is present in 53% of patients with a MoM total hip arthroplasty, of which 40% were asymptomatic. Patients with thick-walled cystic and solid lesions were more likely to be symptomatic and undergo revision. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Factors affecting coastal wetland loss and restoration

    USGS Publications Warehouse

    Cahoon, D.R.; Phillips, S.W.

    2007-01-01

    Opening paragraph: Tidal and nontidal wetlands in the Chesapeake Bay watershed provide vital hydrologic, water-quality, and ecological functions. Situated at the interface of land and water, these valuable habitats are vulnerable to alteration and loss by human activities including direct conversion to non-wetland habitat by dredge-and-fill activities from land development, and to the effects of excessive nutrients, altered hydrology and runoff, contaminants, prescribed fire management, and invasive species. Processes such as sea-level rise and climate change also impact wetlands. Although local, State, and Federal regulations provide for protection of wetland resources, the conversion and loss of wetland habitats continue in the Bay watershed. Given the critical values of wetlands, the Chesapeake 2000 Agreement has a goal to achieve a net gain in wetlands by restoring 25,000 acres of tidal and nontidal wetlands by 2010. The USGS has synthesized findings on three topics: (1) sea-level rise and wetland loss, (2) wetland restoration, and (3) factors affecting wetland diversity.

  2. Assessing Cognitive and Affective Empathy Through the Interpersonal Reactivity Index: An Argument Against a Two-Factor Model.

    PubMed

    Chrysikou, Evangelia G; Thompson, W Jake

    2016-12-01

    One aspect of higher order social cognition is empathy, a psychological construct comprising a cognitive (recognizing emotions) and an affective (responding to emotions) component. The complex nature of empathy complicates the accurate measurement of these components. The most widely used measure of empathy is the Interpersonal Reactivity Index (IRI). However, the factor structure of the IRI as it is predominantly used in the psychological literature differs from Davis's original four-factor model in that it arbitrarily combines the subscales to form two factors: cognitive and affective empathy. This two-factor model of the IRI, although popular, has yet to be examined for psychometric support. In the current study, we examine, for the first time, the validity of this alternative model. A confirmatory factor analysis showed poor model fit for this two-factor structure. Additional analyses offered support for the original four-factor model, as well as a hierarchical model for the scale. In line with previous findings, females scored higher on the IRI than males. Our findings indicate that the IRI, as it is currently used in the literature, does not accurately measure cognitive and affective empathy and highlight the advantages of using the original four-factor structure of the scale for empathy assessments. © The Author(s) 2015.

  3. Factors Affecting Physicians’ Responses to Patients’ Requests for Antidepressants: Focus Group Study

    PubMed Central

    Silberman, Jordan; Paterniti, Debora A.; Kravitz, Richard L.; Epstein, Ronald M.

    2007-01-01

    Background The ways in which patients’ requests for antidepressants affect physicians’ prescribing behavior are poorly understood. Objective To describe physicians’ affective and cognitive responses to standardized patients’ (SPs) requests for antidepressants, as well as the attitudinal and contextual factors influencing prescribing behavior. Design Focus group interviews and brief demographic questionnaires. Participants Twenty-two primary care physicians in 6 focus groups; all had participated in a prior RCT of the influence of patients’ requests on physicians’ prescribing. Measurements Iterative review of interview transcripts, involving qualitative coding and thematic analysis. Results Physicians participating in the focus groups were frequently unaware of and denied the degree to which their thinking was biased by patient requests, but were able to recognize such biases after facilitated reflection. Common affective responses included annoyance and empathy. Common cognitive reactions resulted in further diagnostic inquiry or in acquiescing to the patient’s demands to save time or build the patient–clinician relationship. Patients’ requests for medication prompted the participants to err on the side of overtreating versus careful review of clinical indications. Lack of time and participants’ attitudes—toward the role of the patient and the pharmaceutical ads—also influenced their responses, prompting them to interpret patient requests as diagnostic clues or opportunities for efficiency. Conclusions This study provides a taxonomy of affective and cognitive responses to patients’ requests for medications and the underlying attitudes and contextual factors influencing them. Improved capacity for moment-to-moment self-awareness during clinical reasoning processes may increase the appropriateness of prescribing. PMID:17987348

  4. Method to determine the position-dependant metal correction factor for dose-rate equivalent laser testing of semiconductor devices

    DOEpatents

    Horn, Kevin M.

    2013-07-09

    A method reconstructs the charge collection from regions beneath opaque metallization of a semiconductor device, as determined from focused laser charge collection response images, and thereby derives a dose-rate dependent correction factor for subsequent broad-area, dose-rate equivalent, laser measurements. The position- and dose-rate dependencies of the charge-collection magnitude of the device are determined empirically and can be combined with a digital reconstruction methodology to derive an accurate metal-correction factor that permits subsequent absolute dose-rate response measurements to be derived from laser measurements alone. Broad-area laser dose-rate testing can thereby be used to accurately determine the peak transient current, dose-rate response of semiconductor devices to penetrating electron, gamma- and x-ray irradiation.

  5. Factors Affecting Christian Parents' School Choice Decision Processes: A Grounded Theory Study

    ERIC Educational Resources Information Center

    Prichard, Tami G.; Swezey, James A.

    2016-01-01

    This study identifies factors affecting the decision processes for school choice by Christian parents. Grounded theory design incorporated interview transcripts, field notes, and a reflective journal to analyze themes. Comparative analysis, including open, axial, and selective coding, was used to reduce the coded statements to five code families:…

  6. The Relationships among Adult Affective Factors, Engagement in Science, and Scientific Competencies

    ERIC Educational Resources Information Center

    Tsai, Chun-Yen; Li, Yuh-Yuh; Cheng, Ying-Yao

    2017-01-01

    This study investigated the relationship among adult affective factors, engagement in science, and scientific competencies. Probability proportional to size sampling was used to select 504 participants between the ages of 18 and 70 years. Data were collected through individual face-to-face interviews. The results of hierarchical regression…

  7. Factors Affecting the Happiness of Urban Elementary School Students: An Exploratory Study

    ERIC Educational Resources Information Center

    Tenney, Jodiann K.

    2011-01-01

    The purpose of this transformative mixed methods study was to examine the school happiness of upper elementary students in three Connecticut urban demonstration schools. The study examined the differences in students' happiness based on ethnicity, gender, and their interaction. It also investigated the factors that affect students' happiness in…

  8. Factors Affecting Literacy Achievement of Eighth Grade Middle School Instrumental Music Students

    ERIC Educational Resources Information Center

    Kurt, Johnny T.

    2010-01-01

    The purpose of this pretest-posttest comparative efficacy study was to analyze factors affecting literacy achievement of eighth grade middle school instrumental music students (n = 38) including (a) socioeconomic status (SES), (b) gender, (c) grade point average (GPA), (d) music motivation, (e) music involvement, and (f) instrument section. The…

  9. Trace metal pyritization variability in response to mangrove soil aerobic and anaerobic oxidation processes.

    PubMed

    Machado, W; Borrelli, N L; Ferreira, T O; Marques, A G B; Osterrieth, M; Guizan, C

    2014-02-15

    The degree of iron pyritization (DOP) and degree of trace metal pyritization (DTMP) were evaluated in mangrove soil profiles from an estuarine area located in Rio de Janeiro (SE Brazil). The soil pH was negatively correlated with redox potential (Eh) and positively correlated with DOP and DTMP of some elements (Mn, Cu and Pb), suggesting that pyrite oxidation generated acidity and can affect the importance of pyrite as a trace metal-binding phase, mainly in response to spatial variability in tidal flooding. Besides these aerobic oxidation effects, results from a sequential extraction analyses of reactive phases evidenced that Mn oxidized phase consumption in reaction with pyrite can be also important to determine the pyritization of trace elements. Cumulative effects of these aerobic and anaerobic oxidation processes were evidenced as factors affecting the capacity of mangrove soils to act as a sink for trace metals through pyritization processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Multivariate statistical analysis of heavy metal concentration in soils of Yelagiri Hills, Tamilnadu, India--spectroscopical approach.

    PubMed

    Chandrasekaran, A; Ravisankar, R; Harikrishnan, N; Satapathy, K K; Prasad, M V R; Kanagasabapathy, K V

    2015-02-25

    Anthropogenic activities increase the accumulation of heavy metals in the soil environment. Soil pollution significantly reduces environmental quality and affects the human health. In the present study soil samples were collected at different locations of Yelagiri Hills, Tamilnadu, India for heavy metal analysis. The samples were analyzed for twelve selected heavy metals (Mg, Al, K, Ca, Ti, Fe, V, Cr, Mn, Co, Ni and Zn) using energy dispersive X-ray fluorescence (EDXRF) spectroscopy. Heavy metals concentration in soil were investigated using enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF) and pollution load index (PLI) to determine metal accumulation, distribution and its pollution status. Heavy metal toxicity risk was assessed using soil quality guidelines (SQGs) given by target and intervention values of Dutch soil standards. The concentration of Ni, Co, Zn, Cr, Mn, Fe, Ti, K, Al, Mg were mainly controlled by natural sources. Multivariate statistical methods such as correlation matrix, principal component analysis and cluster analysis were applied for the identification of heavy metal sources (anthropogenic/natural origin). Geo-statistical methods such as kirging identified hot spots of metal contamination in road areas influenced mainly by presence of natural rocks. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Concentrations of metals in tissues of lowbush blueberry (Vaccinium angustifolium) near a copper-nickel smelter at Sudbury, Ontario, Canada: A factor analytic approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bagatto, G.; Shorthouse, J.D.; Crowder, A.A.

    1993-10-01

    Ecosystems damaged by emissions from the copper-nickel smelters of Inco and Falconbridge Ltd. near Sudbury, Ontario, Canada have provided a unique opportunity to study the effects of metal particulates and sulphur dioxide fumigations on plant and animal communities. The most infamous terrain in the Sudbury region is nearest the smelters (two active and one closed), where nearly all vegetation has been destroyed and soils eroded and contaminated. However, over all the past twenty years, some species of plants have developed a tolerance to polluted soils and some denuded lands have been naturally and artificially revegetated. Furthermore, a series of uniquemore » anthropogenic forests have developed away from the smelters. Several studies on the accumulation of metals in plant tissues indicate the levels of metals are usually highest closest to the smelters. Consequently, several studies have reported high correlations between plant concentrations of certain metals with distance from the source of pollution. However, tissue metal burdens are not always correlated with distance from the emission source, suggesting that other biological and physico-chemical factors may influence tissue metal burdens in the Sudbury habitat. The present study provides information on the metal burdens in another plant, lowbush blueberry, growing both near and away from the smelters. This study assesses the apparent influence of the Sudbury smelting operations on plant tissue burdens of five additional elements, along with copper and nickel, by using a factor analytic approach. This approach will allow determination of underlying factors which govern tissue metal burdens in a polluted environment and helps to refine the future direction of research in the Sudbury ecosystem. 12 refs., 2 tabs.« less

  12. Factor affecting happiness among nursing students in South Korea.

    PubMed

    Jun, W H; Jo, M J

    2016-08-01

    WHAT IS KNOWN ON THE SUBJECT?: Despite the increased interest in nursing students' happiness in South Korea, few studies have attempted to identify factors influencing their happiness. Therefore, nursing educators should consistently investigate the factors influencing happiness and develop strategies to improve happiness among Korean nursing students. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: This study confirmed that there were positive correlations between grateful disposition, social support and happiness. In addition, grateful disposition and support from intimate people were identified as predictors of happiness in Korean nursing students. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Development of intervention programmes to help nursing students increase grateful disposition and support from intimate people may be helpful for improving happiness. These programmes can include activity, such as writing a gratitude journal, and extracurricular programmes, such as mentoring programmes between seniors and juniors and/or professor and student. Introduction Happiness is very important in the training and development of nursing students as future nurses. However, nursing students experience a high level of stress and low level of happiness in South Korea. Aim This study aimed to investigate factors that affect happiness among nursing students in South Korea. Method Data were collected from a total of 241 nursing enrolled in two 4-year baccalaureate nursing programmes in South Korea, using a self-administrated questionnaire. To identify predictors of happiness, stepwise regression analysis was conducted. Results The results indicated that grateful disposition and support from intimate people significantly predict happiness among Korean nursing students. These two factors accounted for 38.0% of the variance in happiness. Discussion This study indicated grateful disposition and support from intimate people as factors promoting happiness in nursing students. The findings

  13. Elevated CO2 levels affects the concentrations of copper and cadmium in crops grown in soil contaminated with heavy metals under fully open-air field conditions.

    PubMed

    Guo, Hongyan; Zhu, Jianguo; Zhou, Hui; Sun, Yuanyuan; Yin, Ying; Pei, Daping; Ji, Rong; Wu, Jichun; Wang, Xiaorong

    2011-08-15

    Elevated CO(2) levels and the increase in heavy metals in soils through pollution are serious problems worldwide. Whether elevated CO(2) levels will affect plants grown in heavy-metal-polluted soil and thereby influence food quality and safety is not clear. Using a free-air CO(2) enrichment (FACE) system, we investigated the impacts of elevated atmospheric CO(2) on the concentrations of copper (Cu) or cadmium (Cd) in rice and wheat grown in soil with different concentrations of the metals in the soil. In the two-year study, elevated CO(2) levels led to lower Cu concentrations and higher Cd concentrations in shoots and grain of both rice and wheat grown in the respective contaminated soil. Elevated CO(2) levels slightly but significantly lowered the pH of the soil and led to changes in Cu and Cd fractionation in the soil. Our study indicates that elevated CO(2) alters the distribution of contaminant elements in soil and plants, thereby probably affecting food quality and safety.

  14. How social factors and behavioural strategies affect feeding and social interaction patterns in pigs.

    PubMed

    Boumans, Iris J M M; de Boer, Imke J M; Hofstede, Gert Jan; Bokkers, Eddie A M

    2018-04-26

    Animals living in groups compete for food resources and face food conflicts. These conflicts are affected by social factors (e.g. competition level) and behavioural strategies (e.g. avoidance). This study aimed to deepen our understanding of the complex interactions between social factors and behavioural strategies affecting feeding and social interaction patterns in animals. We focused on group-housed growing pigs, Sus scrofa, which typically face conflicts around the feeder, and of which patterns in various competitive environments (i.e. pig:feeder ratio) have been documented soundly. An agent-based model was developed to explore how interactions among social factors and behavioural strategies can affect various feeding and social interaction patterns differently under competitive situations. Model results show that pig and diet characteristics interact with group size and affect daily feeding patterns (e.g. feed intake and feeding time) and conflicts around the feeder. The level of competition can cause a turning point in feeding and social interaction patterns. Beyond a certain point of competition, meal-based (e.g. meal frequency) and social interaction patterns (e.g. displacements) are determined mainly by behavioural strategies. The average daily feeding time can be used to predict the group size at which this turning point occurs. Under the model's assumptions, social facilitation was relatively unimportant in the causation of behavioural patterns in pigs. To validate our model, simulated patterns were compared with empirical patterns in conventionally housed pigs. Similarities between empirical and model patterns support the model results. Our model can be used as a tool in further research for studying the effects of social factors and group dynamics on individual variation in feeding and social interaction patterns in pigs, as well as in other animal species. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Metal elution from Ni- and Fe-based alloy reactors under hydrothermal conditions.

    PubMed

    Faisal, Muhammad; Quitain, Armando T; Urano, Shin-Ya; Daimon, Hiroyuki; Fujie, Koichi

    2004-05-20

    Elution of metals from Ni- and Fe-based alloy (i.e. Inconel 625 and SUS 316) under hydrothermal conditions was investigated. Results showed that metals could be eluted even in a short contact time. At subcritical conditions, a significant amount of Cr was extracted from SUS 316, while only traces of Ni, Fe, Mo, and Mn were eluted. In contrast, Ni was removed in significant amounts compared to Cr when Inconel 625 was tested. Several factors including temperature and contact time were found to affect elution behavior. The presence of air in the fluid even promoted elution under subcritical conditions.

  16. Factors affecting aggression in South Korean middle school students.

    PubMed

    Park, MiJeong; Choi, Jihea; Lim, Seung-Joo

    2014-12-01

    The study was undertaken to assess levels of aggression, and to determine factors affecting aggression among South Korean middle school students. A descriptive study was conducted using self-report questionnaires. The participants were 340 girls and boys from two middle schools and 302 questionnaires were used for the final data analysis. Aggression, academic stress, depression, self esteem, decision-making competency, and happiness were measured. Data were analyzed using descriptive statistics including t tests, one-way analysis of variance, Pearson's correlation coefficients and multiple regressions. Aggression had significant correlations with academic stress (r = .21, p < .001), depression (r = .43, p < .001), self esteem (r = -.25, p < .001), decision-making competency (r = -.25, p < .001), and happiness (r = -.21, p < .001). Mean score for aggression was 2.49 out of 5. Significant explanatory variables for aggression were grade (t = 4.39, p < .001), academic stress (t = 2.78, p = .006), and depression (t = 5.03, p < .001). The explanatory power of these factors was 26.9%, and this was statistically significant (F = 16.06, p < .001). Findings indicate that depression, academic stress, and grade (second grade) influence aggression. To decrease aggressive behavior, it is necessary to provide systematic and political programs in schools and local communities that can ameliorate negative emotional factors like depression and academic stress. Additionally, development of positive factors such as self esteem, decision-making skills, and happiness in middle school students is important to reduce aggression. Copyright © 2014. Published by Elsevier B.V.

  17. Migration and speciation of heavy metal in salinized mine tailings affected by iron mining.

    PubMed

    Zhang, Xu; Yang, Huanhuan; Cui, Zhaojie

    2017-10-01

    The negative effects of heavy metals have aroused much attention due to their high toxicity to human beings. Migration and transformation trend of heavy metals have a close relationship with soil safety. Researching on migration and transformation of heavy metals in tailings can provide a reliable basis for pollution management and ecosystem restoration. Heavy metal speciation plays an important role in risk assessment. We chose Anshan tailings for our study, including field investigations and laboratory research. Four typical heavy metal elements of mine tailings {Fe (373.89 g/kg), Mn (2,303.80 mg/kg), Pb (40.99 mg/kg) and Cr (199.92 mg/kg)} were studied via Tessier test in vertical and horizontal direction. The main speciation of heavy metals in Anshan tailings was the residual. However, heavy metals have a strong ability for migration and transformation in vertical and horizontal directions. Its tendency to change from stable to unstable speciation results in increasing bioavailability and potential bioavailability. Fe, Mn, Pb and Cr showed different ability in the migration and transformation process (Mn > Pb > Fe > Cr) depending on the characteristics of heavy metals and physicochemical properties of the environment.

  18. Metal Mixture Modeling Evaluation project: 2. Comparison of four modeling approaches

    USGS Publications Warehouse

    Farley, Kevin J.; Meyer, Joe; Balistrieri, Laurie S.; DeSchamphelaere, Karl; Iwasaki, Yuichi; Janssen, Colin; Kamo, Masashi; Lofts, Steve; Mebane, Christopher A.; Naito, Wataru; Ryan, Adam C.; Santore, Robert C.; Tipping, Edward

    2015-01-01

    As part of the Metal Mixture Modeling Evaluation (MMME) project, models were developed by the National Institute of Advanced Industrial Science and Technology (Japan), the U.S. Geological Survey (USA), HDR⎪HydroQual, Inc. (USA), and the Centre for Ecology and Hydrology (UK) to address the effects of metal mixtures on biological responses of aquatic organisms. A comparison of the 4 models, as they were presented at the MMME Workshop in Brussels, Belgium (May 2012), is provided herein. Overall, the models were found to be similar in structure (free ion activities computed by WHAM; specific or non-specific binding of metals/cations in or on the organism; specification of metal potency factors and/or toxicity response functions to relate metal accumulation to biological response). Major differences in modeling approaches are attributed to various modeling assumptions (e.g., single versus multiple types of binding site on the organism) and specific calibration strategies that affected the selection of model parameters. The models provided a reasonable description of additive (or nearly additive) toxicity for a number of individual toxicity test results. Less-than-additive toxicity was more difficult to describe with the available models. Because of limitations in the available datasets and the strong inter-relationships among the model parameters (log KM values, potency factors, toxicity response parameters), further evaluation of specific model assumptions and calibration strategies is needed.

  19. A Multivariate Evaluation of Factors Affecting the Quality of Freshly Frozen Tissue Specimens.

    PubMed

    Wang, Tong-Hong; Chen, Chin-Chuan; Liang, Kung-Hao; Chen, Chi-Yuan; Chuang, Wen-Yu; Ueng, Shir-Hwa; Chu, Pao-Hsien; Huang, Chung-Guei; Chen, Tse-Ching; Hsueh, Chuen

    2017-08-01

    Well-prepared and preserved freshly frozen specimens are indispensable materials for clinical studies. To manage specimen quality and to understand the factors potentially affecting specimen quality during preservation processes, we analyzed the quality of RNA and genomic DNA of various tissues collected between 2002 and 2011 in Linkou Chang Gung Memorial Hospital, Taiwan. During this period, a total of 1059 freshly frozen specimens from eight major cancer categories were examined. It was found that preservation duration, organ origin, and tissue type could all influence the quality of RNA samples. The increased preservation period correlated with decreased RNA quality; the brain, breast, and stomach RNA specimens displayed faster degradation rates than those of other organs, and RNA specimens isolated from tumor tissues were apparently more stable than those of other tissues. These factors could all be used as quality predictors of RNA quality. In contrast, almost all analyses revealed that the genomic DNA samples had good quality, which was not influenced by the aforementioned factors. The results assisted us in determining preservation factors that affect specimen quality, which could provide evidence for improving processes of sample collection and preservation. Furthermore, the results are also useful for researchers to adopt as the evaluation criteria for choosing specimen collection and preservation strategies.

  20. [Factors affecting maternal physical activities: an analysis based on the structural equation modeling].

    PubMed

    Liu, Yi; Luo, Bi-Ru

    2016-11-20

    To analyze the factors affecting maternal physical activities at different stages among pregnant women. Self-designed questionnaires were used to investigate the physical activities of women in different stages, including 650 in the first, 650 in the second, and 750 in the third trimester of pregnancy. The factors affecting maternal physical activities were analyzed using the structural equation model that comprised 4 latent variables (attitude, norm, behavioral attention and behavior) with observed variables that matched the latent variables. The participants ranged from 18 to 35 years of age. The women and their husbands, but not their mothers or mothers-in-law, were all well educated. The caregiver during pregnancy was mostly the mother followed by the husband. For traveling, the women in the first, second and third trimesters preferred walking, bus, and personal escort, respectively; the main physical activity was walking in all trimesters, and the women in different trimester were mostly sedentary, a greater intensity of exercise was associated with less exercise time. Structural equation modeling (SEM) analysis showed that the physical activities of pregnant women was affected by behavioral intention (with standardized regression coefficient of 0.372); attitude and subjective norms affected physical activity by indirectly influencing the behavior intention (standardized regression coefficients of 0.140 and 0.669). The pregnant women in different stages have inappropriate physical activities with insufficient exercise time and intensity. The subjective norms affects the physical activities of the pregnant women by influencing their attitudes and behavior intention indirectly, suggesting the need of health education of the caregivers during pregnancy.

  1. Basic Factors that Affect General Academic Motivation Levels of Candidate Preschool Teachers

    ERIC Educational Resources Information Center

    Celikoz, Nadir

    2010-01-01

    The purpose of this study is to investigate some personal and familial factors that affect overall academic motivation levels of candidate preschool teachers. The study group of this research consists of 285 students attending the child development and preschool education department at Selcuk University Faculty of Vocational Education in the…

  2. Soil fertility and plant diversity enhance microbial performance in metal-polluted soils.

    PubMed

    Stefanowicz, Anna M; Kapusta, Paweł; Szarek-Łukaszewska, Grażyna; Grodzińska, Krystyna; Niklińska, Maria; Vogt, Rolf D

    2012-11-15

    This study examined the effects of soil physicochemical properties (including heavy metal pollution) and vegetation parameters on soil basal respiration, microbial biomass, and the activity and functional richness of culturable soil bacteria and fungi. In a zinc and lead mining area (S Poland), 49 sites were selected to represent all common plant communities and comprise the area's diverse soil types. Numerous variables describing habitat properties were reduced by PCA to 7 independent factors, mainly representing subsoil type (metal-rich mining waste vs. sand), soil fertility (exchangeable Ca, Mg and K, total C and N, organic C), plant species richness, phosphorus content, water-soluble heavy metals (Zn, Cd and Pb), clay content and plant functional diversity (based on graminoids, legumes and non-leguminous forbs). Multiple regression analysis including these factors explained much of the variation in most microbial parameters; in the case of microbial respiration and biomass, it was 86% and 71%, respectively. The activity of soil microbes was positively affected mainly by soil fertility and, apparently, by the presence of mining waste in the subsoil. The mining waste contained vast amounts of trace metals (total Zn, Cd and Pb), but it promoted microbial performance due to its inherently high content of macronutrients (total Ca, Mg, K and C). Plant species richness had a relatively strong positive effect on all microbial parameters, except for the fungal component. In contrast, plant functional diversity was practically negligible in its effect on microbes. Other explanatory variables had only a minor positive effect (clay content) or no significant influence (phosphorus content) on microbial communities. The main conclusion from this study is that high nutrient availability and plant species richness positively affected the soil microbes and that this apparently counteracted the toxic effects of metal contamination. Copyright © 2012 Elsevier B.V. All rights

  3. Factors affecting trip generation of motorcyclist for the purpose of non-mandatory activities

    NASA Astrophysics Data System (ADS)

    Anggraini, Renni; Sugiarto, Sugiarto; Pramanda, Heru

    2017-11-01

    The inadequate facilities and limited access to public transport reflect many people using private vehicles, in particular, motorcycle. The motorcycle is most widely used in Indonesia, recently, including Aceh Province. As a result, the number of motorcycle ownership is increasing significantly. The increasing number of motorcycles leads to complex traffic problems. Several factors tend to affect the trip generation of the motorcyclist, i.e., the social demographics of individuals and families, accessibility, etc. This study aims to analyze the characteristics of motorcyclists for non-mandatory activities, i.e. activities other than to work and school. It also aims to determine the dominant factors that affect their trips through trip generation models. The required data consist of primary data and secondary data. Primary data consists of a home interview survey that collects individual's daily trips. It is conducted by distributing the questionnaires to 400 families residing in Lhokseumawe City. Modeling the trip generation of the motorcyclist is done by multiple linear regression analysis. Parameters calibration uses OLS (Ordinary Least Square) method. The results showed that the dominant variables that affect the trip generation of motorcyclist for non-mandatory activities are license ownership, housewife, school-age children, middle-income household, and lower education level. It can be concluded that some factors affecting trip generation to non-work activities were female motorcyclists from the middle-income household with lower education level. As their status is mostly as the housewife, escorting children to non-school activities seems to the mother's task, instead of the father. It is clear that, most female ride motorcycle for doing household tasks. However, it should be noted that the use of the motorcycle in long-term does not suit for sustainable transportation.

  4. Eating habits and factors affecting food choice of adolescents living in rural areas.

    PubMed

    Bargiota, Alexandra; Pelekanou, Maria; Tsitouras, Andreas; Koukoulis, Georgios N

    2013-01-01

    To establish factors that affect food choices among adolescents living in rural areas and to identify their food choices. A random sample of adolescents living in a Greek rural area (n=382) aged 12-18 years were individually interviewed. Food consumption was assessed by a semi-quantitative food-frequency questionnaire and adherence to the Mediterranean diet was evaluated using the KIDMED questionnaire. Information was collected regarding self-perceived body size, dieting, dietary knowledge, parental control, meal and snack frequency, eating out of home, eating takeaways and precooked meals, eating from the school canteen. Body image concerns, dieting, education about food, parental control, maternal education level and eating with family and peers are factors that were found to affect food choices in this group of Greek adolescents. The adherence to the Mediterranean diet was low (KIDMED index was 4.5±2.7). Regular family meals at home were frequent in this group and 99% of the adolescents ate lunch daily at home. Eating out with peers and eating from the school canteen was related with higher consumption of 'junk type of food'. Girls and younger adolescents and those whose mothers had a higher education level seem to make healthier choices. Factors such as personal issues, family and peer pressure significantly affect food choices among adolescents living in a Greek rural area and highlight the importance of implementing multilevel strategies to promote healthy eating among adolescents.

  5. Analyzing the Factors Affecting the Success in University Entrance Examination through the use of Artificial Neural Networks

    ERIC Educational Resources Information Center

    Agdelen, Zafer; Haydar, Ali; Kanani, Andisheh

    2007-01-01

    There are many factors that affect the success of students in university entrance examination. These factors can be mainly categorized as follows; social factors, environmental factors, economical factors etc. The main aim of this study is to find whether there is a relation between these factors and the success in the university entrance…

  6. Trace metal dynamics in floodplain soils of the river Elbe: a review.

    PubMed

    Schulz-Zunkel, Christiane; Krueger, Frank

    2009-01-01

    This paper reviews trace metal dynamics in floodplain soils using the Elbe floodplains in Germany as an example of extraordinary importance because of the pollution level of its sediments and soils. Trace metal dynamics are determined by processes of retention and release, which are influenced by a number of soil properties including pH value, redox potential, organic matter, type and amount of clay minerals, iron-, manganese- and aluminum-oxides. Today floodplains act as important sinks for contaminants but under changing hydraulic and geochemical conditions they may also act as sources for pollutants. In floodplains such changes may be extremes in flooding or dry periods that particularly lead to altered redox potentials and that in turn influence the pH value, the mineralization of organic matter as well as the charge of the pedogenic oxides. Such reactions may affect the bioavailability of trace metals in soils and it can be clearly seen that the bioavailability of metals is an important factor for estimating trace metal remobilization in floodplain soils. However as bioavailability is not a constant factor, there is still a lack of quantification of metal mobilization particularly on the basis of changing geochemical conditions. Moreover, mobile amounts of metals in the soil solution do not indicate to which extent remobilized metals will be transported to water bodies or plants and therefore potentially have toxicological effects. Consequently, floodplain areas still need to be taken into consideration when studying the role and behavior of sediments and soils for transporting pollutants within river systems, particularly concerning the Water Framework Directive.

  7. Experimental determination of the Mo isotope fractionation factor between metal and silicate liquids

    NASA Astrophysics Data System (ADS)

    Hin, R. C.; Burkhardt, C.; Schmidt, M. W.; Bourdon, B.

    2011-12-01

    before chemical purification. Initial results provide an equilibrium 98Mo/95Mo isotope fractionation factor between metal and silicate liquids of -0.18±0.10% (2σ) at 1400°C and 1 GPa. Although the relative mass difference of these Mo isotopes is smaller than for Fe isotopes, this result implies that metal-silicate segregation may have led to mass-dependent stable Mo isotope fractionation, as opposed to Fe isotopes. A possible explanation is that the bonding environment of Mo may counterbalance its relatively small mass separation. At reducing conditions, Mo occurs in 4+ valence state in silicates [4] and thus its bond strength difference between metal and silicate may be more similar to that of Si than Fe. Stable Mo isotopes may thus become an important tool for constraining the conditions of core formation in asteroids and terrestrial planets. [1] Rubie et al. (2011) EPSL 301, 31-42. [2] Shahar et al. (2009) EPSL 288, 228-234. [3] Poitrasson et al. (2009) EPSL 278, 376-385. [4] Farges et al. (2006) Can. Min. 44, 731-753.

  8. Toxicity of heavy metals and metal-containing nanoparticles on plants.

    PubMed

    Mustafa, Ghazala; Komatsu, Setsuko

    2016-08-01

    Plants are under the continual threat of changing climatic conditions that are associated with various types of abiotic stresses. In particular, heavy metal contamination is a major environmental concern that restricts plant growth. Plants absorb heavy metals along with essential elements from the soil and have evolved different strategies to cope with the accumulation of heavy metals. The use of proteomic techniques is an effective approach to investigate and identify the biological mechanisms and pathways affected by heavy metals and metal-containing nanoparticles. The present review focuses on recent advances and summarizes the results from proteomic studies aimed at understanding the response mechanisms of plants under heavy metal and metal-containing nanoparticle stress. Transport of heavy metal ions is regulated through the cell wall and plasma membrane and then sequestered in the vacuole. In addition, the role of different metal chelators involved in the detoxification and sequestration of heavy metals is critically reviewed, and changes in protein profiles of plants exposed to metal-containing nanoparticles are discussed in detail. Finally, strategies for gaining new insights into plant tolerance mechanisms to heavy metal and metal-containing nanoparticle stress are presented. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Bioremediation mechanisms of combined pollution of PAHs and heavy metals by bacteria and fungi: A mini review.

    PubMed

    Liu, Shao-Heng; Zeng, Guang-Ming; Niu, Qiu-Ya; Liu, Yang; Zhou, Lu; Jiang, Lu-Hua; Tan, Xiao-Fei; Xu, Piao; Zhang, Chen; Cheng, Min

    2017-01-01

    In recent years, knowledge in regard to bioremediation of combined pollution of polycyclic aromatic hydrocarbons (PAHs) and heavy metals by bacteria and fungi has been widely developed. This paper reviews the species of bacteria and fungi which can tackle with various types of PAHs and heavy metals entering into environment simultaneously or successively. Microbial activity, pollutants bioavailability and environmental factors (e.g. pH, temperature, low molecular weight organic acids and humic acids) can all affect the bioremediation of PAHs and heavy metals. Moreover, this paper summarizes the remediation mechanisms of PAHs and heavy metals by microbes via elucidating the interaction mechanisms of heavy metals with heavy metals, PAHs/PAHs metabolites with PAHs and PAHs with heavy metals. Based on the above reviews, this paper also discusses the potential research needs for this field. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Factors affecting birth weight in sheep: maternal environment

    PubMed Central

    Gardner, D S; Buttery, P J; Daniel, Z; Symonds, M E

    2007-01-01

    Knowledge of factors affecting variation in birth weight is especially important given the relationship of birth weight to neonatal and adult health. The present study utilises two large contemporary datasets in sheep of differing breeds to explore factors that influence weight at term. For dataset one (Study 1; n = 154 Blue-faced Leicester×Swaledale (Mule) and 87 Welsh Mountain ewes, 315 separate cases of birth weight), lamb birth weight as the outcome measure was related to maternal characteristics and individual energy intake of the ewe during specified periods of gestation, i.e. early (1-30 days; term ∼147 days gestation), mid (31-80 days) or late (110-147 days) pregnancy. For dataset two (Study 2; n = 856 Mule ewes and 5821 cases of birth weight), we investigated using multilevel modelling the influence of ewe weight, parity, barrenness, lamb sex, litter size, lamb mortality and year of birth on lamb birth weight. For a subset of these ewes (n = 283), the effect of the ewes’ own birth weight was also examined. Interactions between combinations of variables were selectively investigated. Litter size, as expected, had the single greatest influence on birth weight with other significant effects being year of birth, maternal birth weight, maternal nutrition, sex of the lamb, ewe barrenness and maternal body composition at mating. The results of the present study have practical implications not only for sheep husbandry but also for the increased knowledge of factors that significantly influence variation in birth weight; as birth weight itself has become a significant predictor of later health outcomes. PMID:17244755

  11. Durability of metals from archaeological objects, metal meteorites, and native metals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, A.B. Jr.; Francis, B.

    1980-01-01

    Metal durability is an important consideration in the multi-barrier nuclear waste storage concept. This study summarizes the ancient metals, the environments, and factors which appear to have contributed to metal longevity. Archaeological and radiochemical dating suggest that human use of metals began in the period 6000 to 7000 BC. Gold is clearly the most durable, but many objects fashioned from silver, copper, bronze, iron, lead, and tin have survived for several thousand years. Dry environments, such as tombs, appear to be optimum for metal preservation, but some metals have survived in shipwrecks for over a thousand years. The metal meteoritesmore » are Fe-base alloys with 5 to 60 wt% Ni and minor amounts of Co, I, and S. Some meteoritic masses with ages estimated to be 5,000 to 20,000 years have weathered very little, while other masses from the same meteorites are in advanced stages of weathering. Native metals are natural metallic ores. Approximately five million tonnes were mined from native copper deposits in Michigan. Copper masses from the Michigan deposits were transported by the Pleistocene glaciers. Areas on the copper surfaces which appear to represent glacial abrasion show minimal corrosion. Dry cooling tower technology has demonstrated that in pollution-free moist environments, metals fare better at temperatures above than below the dewpoint. Thus, in moderate temperature regimes, elevated temperatures may be useful rather than detrimental for exposures of metal to air. In liquid environments, relatively complex radiolysis reactions can occur, particularly where multiple species are present. A dry environment largely obviates radiolysis effects.« less

  12. Metal transport and remobilisation in a basin affected by acid mine drainage: the role of ochreous amorphous precipitates.

    PubMed

    Consani, Sirio; Carbone, Cristina; Dinelli, Enrico; Balić-Žunić, Tonci; Cutroneo, Laura; Capello, Marco; Salviulo, Gabriella; Lucchetti, Gabriella

    2017-06-01

    Metal-polluted mine waters represent a major threat to the quality of waters and sediments in a downstream basin. At the confluence between acidic mine waters and the unpolluted waters of the Gromolo Torrent (Liguria, North-West Italy), the massive formation of an ochreous amorphous precipitate takes place. This precipitate forms a soft blanket that covers the torrent bed and can be observed down to its mouth in the sea. The aim of this work is to evaluate the dispersion of metals in the Gromolo Torrent basin from the abandoned Cu-Fe sulphide mine of Libiola to the Ligurian Sea and to assess the metal remobilisation from the amorphous precipitates. The mineralogy of the superficial sediments collected in the torrent bed and the concentrations of different elements of environmental concern (Cu, Zn, Cd, Co, Cr, Mn, Ni, Pb, As, and Sb) were therefore analysed. The results showed that the precipitates contain high concentration of Fe, Al, Cu, and Zn, significantly modifying the bulk chemistry of the Gromolo Torrent sediments. In order to evaluate the possible remobilisation of ecotoxic elements from the amorphous precipitates, bulk leaching tests were performed with both deionised and seawater. Bulk leaching tests with deionised water mobilised primarily high Pb amounts, but also relatively high concentrations of Fe, Al, Cu, and Zn are released in the leachate. In seawater tests, Fe, Al, Cu, and Zn were released in smaller amounts, while other elements like Mn, Cd, Co, and Ni increased in the released fraction. Pb was still strongly released as in deionised water experiments. The results show that the interaction of precipitates and seawater can remobilise high concentrations of metals, thus affecting the surrounding environment.

  13. Strategies to predict metal mobility in surficial mining environments

    USGS Publications Warehouse

    Smith, Kathleen S.

    2007-01-01

    This report presents some strategies to predict metal mobility at mining sites. These strategies are based on chemical, physical, and geochemical information about metals and their interactions with the environment. An overview of conceptual models, metal sources, and relative mobility of metals under different geochemical conditions is presented, followed by a discussion of some important physical and chemical properties of metals that affect their mobility, bioavailability, and toxicity. The physical and chemical properties lead into a discussion of the importance of the chemical speciation of metals. Finally, environmental and geochemical processes and geochemical barriers that affect metal speciation are discussed. Some additional concepts and applications are briefly presented at the end of this report.

  14. Metal-on-Metal Hip Resurfacing Arthroplasty

    PubMed Central

    Sehatzadeh, S; Kaulback, K; Levin, L

    2012-01-01

    Background Metal-on-metal (MOM) hip resurfacing arthroplasty (HRA) is in clinical use as an appropriate alternative to total hip arthroplasty in young patients. In this technique, a metal cap is placed on the femoral head to cover the damaged surface of the bone and a metal cup is placed in the acetabulum. Objectives The primary objective of this analysis was to compare the revision rates of MOM HRA using different implants with the benchmark set by the National Institute of Clinical Excellence (NICE). The secondary objective of this analysis was to review the literature regarding adverse biological effects associated with implant material. Review Methods A literature search was performed on February 13, 2012, to identify studies published from January 1, 2009, to February 13, 2012. Results The revision rates for MOM HRA using 6 different implants were reviewed. The revision rates for MOM HRA with 3 implants met the NICE criteria, i.e., a revision rate of 10% or less at 10 years. Two implants had short-term follow-ups and MOM HRA with one of the implants failed to meet the NICE criteria. Adverse tissue reactions resulting in failure of the implants have been reported by several studies. With a better understanding of the factors that influence the wear rate of the implants, adverse tissue reactions and subsequent implant failure can be minimized. Many authors have suggested that patient selection and surgical technique affect the wear rate and the risk of tissue reactions. The biological effects of high metal ion levels in the blood and urine of patients with MOM HRA implants are not known. Studies have shown an increase in chromosomal aberrations in patients with MOM articulations, but the clinical implications and long-term consequences of this increase are still unknown. Epidemiological studies have shown that patients with MOM HRA implants did not have an overall increase in mortality or risk of cancer. There is insufficient clinical data to confirm the

  15. Individual and School Factors Affecting Students' Participation and Success in Higher Education

    ERIC Educational Resources Information Center

    Shulruf, Boaz; Hattie, John; Tumen, Sarah

    2008-01-01

    The purpose of this study is to identify school factors that affect students' achievements at the secondary and tertiary levels of education. The analysis included data of 9,894 students who studied in Auckland regional secondary schools in 2004. The results indicate that, although student demographic characteristics are associated with students'…

  16. Critical Factors Affecting Students' Satisfaction with Higher Education in Sri Lanka

    ERIC Educational Resources Information Center

    Weerasinghe, I. M. S.; Fernando, R. L. S.

    2018-01-01

    Purpose: The purpose of this study is to explain critical factors affecting student satisfaction levels in selected state universities in Sri Lanka. Design/methodology/approach: The study has applied an quantitative survey design guided by six hypotheses. A conceptual framework has been developed to address the research questions on the basis of a…

  17. Factors That Affect Students' Capacity to Fulfill the Role of Online Learner

    ERIC Educational Resources Information Center

    Comer, Debra R.; Lenaghan, Janet A.; Sengupta, Kaushik

    2015-01-01

    Because most undergraduate students are digital natives, it is widely believed that they will succeed in online courses. But factors other than technology also affect students' ability to fulfill the role of online learner. Self-reported data from a sample of more than 200 undergraduates across multiple online courses indicate that students…

  18. A Study of Students' Attitude toward Teachers' Affective Factors in EFL Classrooms

    ERIC Educational Resources Information Center

    Ranjbar, Nahid Amini; Narafshan, Mehry Haddad

    2016-01-01

    In any teaching-learning situation, teacher plays a significant role in the classroom. This study aimed at investigating the students' attitude toward teachers' affective factors in EFL classrooms. In this study, the students' population was 300 pre-intermediate (based on the institutes' placement test) female EFL students (10 to 25 years old) in…

  19. Exploring the factors affecting motorway accident severity in England using the generalised ordered logistic regression model.

    PubMed

    Michalaki, Paraskevi; Quddus, Mohammed A; Pitfield, David; Huetson, Andrew

    2015-12-01

    The severity of motorway accidents that occurred on the hard shoulder (HS) is higher than for the main carriageway (MC). This paper compares and contrasts the most important factors affecting the severity of HS and MC accidents on motorways in England. Using police reported accident data, the accidents that occurred on motorways in England are grouped into two categories (i.e., HS and MC) according to the location. A generalized ordered logistic regression model is then applied to identify the factors affecting the severity of HS and MC accidents on motorways. The factors examined include accident and vehicle characteristics, traffic and environment conditions, as well as other behavioral factors. Results suggest that the factors positively affecting the severity include: number of vehicles involved in the accident, peak-hour traffic time, and low visibility. Differences between HS and MC accidents are identified, with the most important being the involvement of heavy goods vehicles (HGVs) and driver fatigue, which are found to be more crucial in increasing the severity of HS accidents. Measures to increase awareness of HGV drivers regarding the risk of fatigue when driving on motorways, and especially the nearside lane, should be taken by the stakeholders. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Variation of NEE and its affecting factors in a vineyard of arid region of northwest China

    NASA Astrophysics Data System (ADS)

    Guo, W. H.; Kang, S. Z.; Li, F. S.; Li, S. E.

    2014-02-01

    To understand the variation of net ecosystem CO2 exchange (NEE) in orchard ecosystem and it's affecting factors, carbon flux was measured using eddy covariance system in a wine vineyard in arid northwest China during 2008-2010. Results show that vineyard NEE was positive value at the early growth stage, higher negative value at the mid-growth stage, and lower negative value at the later growth stage. Diurnal variation of NEE was "W" shaped curve in sunny day, but "U" shaped curve in cloudy day. Irrigation and pruning did not affect diurnal variation shape of NEE, however, irrigation reduced the difference between maximal and minimal value of NEE and pruning reduced the carbon sink capacity. The main factors affecting hourly NEE were canopy conductance (gc) and net radiation (Rn). The hourly NEE increased with the increase of gc or Rn when gc was less than 0.02 m·s-1 or Rn was between 0 and 200 W·m-2. The main factors affecting both daily and seasonal NEE were gc, air temperature (Ta), atmospheric CO2 density, vapour pressure deficit (VPD) and soil moisture content.