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Sample records for factors influencing perch

  1. Reappraising factors affecting mourning dove perch coos

    Science.gov (United States)

    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.

  2. Dynamics and Control of Three-Dimensional Perching Maneuver under Dynamic Stall Influence

    Science.gov (United States)

    Feroskhan, Mir Alikhan Bin Mohammad

    Perching is a type of aggressive maneuver performed by the class 'Aves' species to attain precision point landing with a generally short landing distance. Perching capability is desirable on unmanned aerial vehicles (UAVs) due to its efficient deceleration process that potentially expands the functionality and flight envelope of the aircraft. This dissertation extends the previous works on perching, which is mostly limited to two-dimensional (2D) cases, to its state-of-the-art threedimensional (3D) variety. This dissertation presents the aerodynamic modeling and optimization framework adopted to generate unprecedented variants of the 3D perching maneuver that include the sideslip perching trajectory, which ameliorates the existing 2D perching concept by eliminating the undesirable undershoot and reliance on gravity. The sideslip perching technique methodically utilizes the lateral and longitudinal drag mechanisms through consecutive phases of yawing and pitching-up motion. Since perching maneuver involves high rates of change in the angles of attack and large turn rates, introduction of three internal variables thus becomes necessary for addressing the influence of dynamic stall delay on the UAV's transient post-stall behavior. These variables are then integrated into a static nonlinear aerodynamic model, developed using empirical and analytical methods, and into an optimization framework that generates a trajectory of sideslip perching maneuver, acquiring over 70% velocity reduction. An impact study of the dynamic stall influence on the optimal perching trajectories suggests that consideration of dynamic stall delay is essential due to the significant discrepancies in the corresponding control inputs required. A comparative study between 2D and 3D perching is also conducted to examine the different drag mechanisms employed by 2D and 3D perching respectively. 3D perching is presented as a more efficient deceleration technique with respect to spatial costs and

  3. The use of artificial spawning substrates in order to understand the factors influencing the spawning site selection, depth of egg strands deposition and hatching time of perch (Perca fluviatilis L.

    Directory of Open Access Journals (Sweden)

    Jan Kubečka

    2012-01-01

    Full Text Available The distribution of egg strands of perch Perca fluviatilis and factors affecting this distribution, in terms of spawning sites and spawning depths used, was studied in spring 2010 in Chabařovice Lake, Czech Republic, using areas with an artificial spawning substrate (A.S.S. and control areas outside the A.S.S. Perch significantly preferred a calm shore instead of a windward shore for spawning. The depths at which perch egg strands were found increased significantly during the spawning period in both A.S.S. areas and in areas outside the A.S.S. (on average from 4.9 m at the beginning to 12.3 m at the end of the spawning period. With increasing depth of deposition the size of the egg strands decreased significantly. The mean depth of egg strands on individual dates corresponded to the position of 10-12°C water layers. From the third week onward, however, egg strands were deposited in much deeper and colder water. A strong relationship was found between the depth at which egg strands were deposited and the duration of the daylight period, indicating that, at the end of the spawning season, perch do not react to the actual temperature of the water column but that they follow their inner clock, assuming that "normally" the shallower depth layers are too warm for successful embryo development. Factors influencing the depth distribution of egg strands were identified as waves, temperature and duration of the daylight period. Factors influencing the selection of spawning sites were identified as wind inducing current, internal seiches and temperature instability of the water column. The first perch larvae were present in the open water of Chabařovice Lake before mid-May, and the latest larvae not earlier than the beginning of July, since warming of the water in deeper layers was very slow. It appears that with prolonged spawning and hatching periods and with spawning occurring at various depths and temperatures, perch have evolved a powerful

  4. Perch availability and ground cover: factors that may constitute ...

    African Journals Online (AJOL)

    In Succulent Karoe, pale chanting goshawks occupied areas where perch density (16 natural and 122 artificial/25 hal was significantly higher than in unoccupied areas (8 natural and 12 artificial/25 hal. The high proportion of cover formed by natural perches (trees and shrubs; 36%) and the low proportion of open ground ...

  5. Enzymatic correlates of energy status in wild yellow perch inhabiting clean and contaminated environments.

    Science.gov (United States)

    Gauthier, Charles; Campbell, Peter G C; Couture, Patrice

    2011-09-01

    Enzymes representing a variety of metabolic pathways were examined in yellow perch (Perca flavescens) collected from a metal-contaminated region (Rouyn-Noranda, Québec, Canada) to determine which were most closely related to fish condition factor, pyloric caeca weight, and visceral lipid accumulation, as well to seek a better understanding of the influence of metal contamination on the physiology and biometrics of perch. Compared to laboratory fish, wild perch were under important energy restrictions. The condition factor of wild fish was correlated with indicators of aerobic metabolism (citrate synthase, cytochrome C oxidase), protein anabolism (nucleoside diphosphokinase), and indicators of lipid accumulation (glucose-6-phosphate dehydrogenase, visceral lipid index). Pyloric caeca weights were well correlated with indicators of protein anabolism, but only when both seasons were examined together, possibly indicating a lag in the response of enzymes to changes in diet. The addition of contaminant stress to existing energy restrictions led to changes in the relationships between enzymes and biometrics, reducing the predictive power of the models for perch in contaminated lakes. The present study broadens our knowledge of the impact of metal contamination on energy accumulation and tissue metabolic capacities in wild perch. Copyright © 2011 SETAC.

  6. Comparative analysis of the shape of the perch from Techa river and Miass river

    Energy Technology Data Exchange (ETDEWEB)

    Osipov, D.; Pryakhin, E. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation); Rudolfsen, G. [Norwegian Radiation Protection Authority (NRPA) and University of Tromsoe (Norway); Yegoreichenkov, E. [Urals Research Center for Radiation Medicine (Russian Federation)

    2014-07-01

    The adaptation to environmental conditions can be accompanied by morphological changes. Description of morphological differences in animal populations could reveal differences habitat, both abiotic and biotic factors. In our study we examined if fish habituating river with different activity concentration of radionuclides differ in geometric morphometry. Geometric morphometry makes it possible to identify morphological differences between objects on the basis of the form, without influence of the 'size factor'. The approach is based on a multivariate analysis of the coordinates of marks, placed on the surface of the morphological object in accordance with certain rules. We used perch (Perca fluviatilis Linnaeus, 1758) as a study species as it is a common, and widespread species of freshwater fish in moderate and subarctic latitudes of Eurasia and North America. Perch is characterized by high flexibility of morphology in relation to environmental differences. We investigated body shape and its changes with the growth in perch that live in Techa River under chronic radiation exposure and perch in the control river Miass. The alignment of digital image tags that characterize the shape of the fish's body, was implemented in the program TPSdig. Further analysis was performed using the package geomorph for R statistical software. The study showed statistically significant (F{sub 1,95}=12.69, p=0.01) differences in body shape of perch from Techa river and Miass river. Perch living in the Techa River are relatively shorter and higher. Further, perch in Techa is characterized by a smaller size of the eyes. For both populations the contribution of allometric component to shape change was observed: smaller animals have a shape similar to the Miass river perch population. With increase of body size, shape of the perch becomes similar to that of the Techa's perch population. Significant differences were observed only for young animals from the two rivers

  7. Perch availability and ground cover: factors that may constitute ...

    African Journals Online (AJOL)

    1996-02-21

    Feb 21, 1996 ... pale chanting goshawks occupied areas where perch density (16 natural and 122 artificial/25 hal was signifi- ... sal and cooperative breeding in pale chanting goshawk families. ...... fortunes in the white-fronted bee-eater.

  8. Effects of predation stress and food ration on perch gut microbiota.

    Science.gov (United States)

    Zha, Yinghua; Eiler, Alexander; Johansson, Frank; Svanbäck, Richard

    2018-02-06

    Gut microbiota provide functions of importance to influence hosts' food digestion, metabolism, and protection against pathogens. Factors that affect the composition and functions of gut microbial communities are well studied in humans and other animals; however, we have limited knowledge of how natural food web factors such as stress from predators and food resource rations could affect hosts' gut microbiota and how it interacts with host sex. In this study, we designed a two-factorial experiment exposing perch (Perca fluviatilis) to a predator (pike, Esox lucius), and different food ratios, to examine the compositional and functional changes of perch gut microbiota based on 16S rRNA amplicon sequencing. We also investigated if those changes are host sex dependent. We showed that overall gut microbiota composition among individual perch significantly responded to food ration and predator presence. We found that species richness decreased with predator presence, and we identified 23 taxa from a diverse set of phyla that were over-represented when a predator was present. For example, Fusobacteria increased both at the lowest food ration and at predation stress conditions, suggesting that Fusobacteria are favored by stressful situations for the host. In concordance, both food ration and predation stress seemed to influence the metabolic repertoire of the gut microbiota, such as biosynthesis of other secondary metabolites, metabolism of cofactors, and vitamins. In addition, the identified interaction between food ration and sex emphasizes sex-specific responses to diet quantity in gut microbiota. Collectively, our findings emphasize an alternative state in gut microbiota with responses to changes in natural food webs depending on host sex. The obtained knowledge from this study provided us with an important perspective on gut microbiota in a food web context.

  9. Perch population assessment in lakes reclaimed using oil-sands derived material

    International Nuclear Information System (INIS)

    Heuvel, M.R. van den; Dixon, D.G.; Power, M.; Boerger, H.; MacKinnon, M.D.; Meer, T. van

    1995-01-01

    The mining and extraction of petroleum products from oil-sands involves large areas of land and produces enormous volumes of tailings. One possible land reclamation option is to incorporate fine-tailings material into the bottoms of constructed lakes capped with natural surface water. The wet landscape method represents potential risk to aquatic biota-naphthenic acids and PAHs elute from pore water contained in the fine-tailings substrate. In spring 1995 yellow perch were stocked into a large-scale (5ha) experimental pond that consisted of fine-tailings capped with natural water as well as into two other reclaimed ponds that were constructed with oil-sands overburden material. Prior to stocking of perch, ponds had colonized with cyprinids, macrophytes and benthic invertebrates over a two year period. Perch were sampled in fall 1995 for age, condition factor, liver size, gonad size, fecundity, stomach contents, liver mixed-function oxygenase activity (MFO), bile PAH metabolites and plasma steroid hormones. When compared to the source lake, perch in the DP did not show reduced reproductive potential. Perch in all of the reclaimed ponds demonstrated exposure to organic compounds as indicated by marginally induced MFO activity and increased liver size. Exposure to naphthenates and PAHs in water as well as ecological environmental factors will be discussed

  10. Distribution of Nile perch Lates niloticus in southern Lake Victoria is ...

    African Journals Online (AJOL)

    Although Nile perch Lates niloticus is assumed to be sensitive to low oxygen concentrations, it was found in deep water in Lake Victoria, where oxygen depletion is common during the rainy season. Since factors determining Nile perch distribution are not well understood its spatial distribution in the Mwanza Gulf of Lake ...

  11. Bioaccumulation of decamethylcyclopentasiloxane in perch in Swedish lakes.

    Science.gov (United States)

    Kierkegaard, Amelie; Bignert, Anders; McLachlan, Michael S

    2013-10-01

    Decamethylcyclopentasiloxane (D5), a high production volume chemical used in personal care products, enters the environment both via air and sewage treatment plant (STP) recipients. It has been found in fish, and there is concern that it may be a bioaccumulative substance. In this work D5 was analyzed in perch from six Swedish lakes that did not receive STP effluent, and in perch and sediment from six lakes that received STP effluent. In the lakes receiving the STP effluent, the D5 concentrations in sediment varied over three orders of magnitude and were correlated with the number of persons connected to the STP normalized to the surface area of the receiving body. In the lakes not receiving effluent, the D5 levels in perch were all below the LOQ, while D5 was above the LOQ in almost all perch from lakes that received effluent. The D5 concentrations in perch and sediment from the lakes receiving STP effluent were correlated. This shows that STP effluent is a much more important source of D5 to aquatic ecosystems than atmospheric deposition, and that the risk of adverse effects of D5 on aquatic life will be greatest in small recipients receiving large amounts of STP effluent. The bioaccumulation of D5 was compared to that of PCB 180 on the basis of multimedia bioaccumulation factors (mmBAFs), which describe the fraction of the contaminant present in the whole aquatic environment (i.e. water and surface sediment) that is transferred to the fish. In four of the six lakes the mmBAF of D5 was >0.3 of the mmBAF of PCB 180. Given that PCB 180 is a known highly bioaccumulative chemical, this indicates that the bioaccumulation of D5 in perch is considerable. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Effect of perches on liver health of hens.

    Science.gov (United States)

    Jiang, S; Hester, P Y; Hu, J Y; Yan, F F; Dennis, R L; Cheng, H W

    2014-07-01

    Fatty liver is a common energy metabolic disorder in caged laying hens. Considering that the egg industry is shifting from conventional cages to alternative housing systems such as enriched cages, the objective of this study was to determine the effects of perches on fat deposition and liver health in laying hens. Three hundred twenty-four 17-wk-old White Leghorn hens were housed in 1 of 4 treatments with 9 hens per cage. Treatment 1 hens never had access to perches during their life cycle. Treatment 2 hens had access to perches during the pullet phase only. Treatment 3 hens had access to perches during the laying phase only. Treatment 4 hens always had access to perches. Liver weight, abdominal fat pad weight, BW, liver fat, and circulating alanine transaminase, aspartate transaminase, and adiponectin were determined. Provision of perches during either the rearing or laying phase did not affect liver health in 71-wk-old hens. However, perch access compared with no perch access during the egg laying phase reduced relative fat pad weight. These results suggest that providing perches as a means of stimulating activity reduced abdominal fat deposition in caged hens during the laying period. However, perch access in caged hens was ineffective in reducing fat deposition in the liver and altering enzyme activities related to improved liver function. © 2014 Poultry Science Association Inc.

  13. Effects of the filamentous cyanobacterium Nodularia on fitness and feeding behavior of young-of-the-year (YOY) Eurasian perch (Perca fluviatilis).

    Science.gov (United States)

    Persson, Karl-Johan; Stenroth, Patrik; Legrand, Catherine

    2011-06-01

    This study reveals that both cyanobacterial toxicity and turbidity have the potential to reduce the growth and energy storage of young-of-the-year (YOY) perch and thereby influence survival rates. During the 1990's a reduction in recruitment of YOY perch (Perca fluviatilis) occurred along the Swedish East coast. Concurrently, large blooms of filamentous cyanobacteria have increased in the Baltic Proper and in coastal waters. This study examined whether extended exposure to toxic and non-toxic filamentous cyanobacterium Nodularia affect YOY perch growth and feeding behavior under simulated bloom conditions (30 days at 50 μg Chl a L(-1)). Specific growth rate (SGR), the somatic condition index (SCI) and the lipid content of YOY perch (10-12 weeks old) were significantly lower in perch exposed to Nodularia compared to fed controls (no Nodularia). YOY perch exposed to non-toxic Nodularia displayed a higher attack rate than perch living in Nodularia free controls in 2 out of 3 trials. Reductions in growth and energy storage, mediated by cyanobacteria, increase the risk of starvation and predation and could locally influence recruitment of YOY perch. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Oviposition site selection and embryo mortality in perch

    Czech Academy of Sciences Publication Activity Database

    Smith, C.; Douglas, A.; Jurajda, Pavel

    2001-01-01

    Roč. 58, č. 3 (2001), s. 880-882 ISSN 0022-1112 Institutional research plan: CEZ:AV0Z6093917 Keywords : spawning * reproduction * Eurasian perch Subject RIV: EG - Zoology Impact factor: 1.249, year: 2001

  15. Monitoring and sampling perched ground water in a basaltic terrain

    International Nuclear Information System (INIS)

    Hubbell, J.M.

    1990-01-01

    Perched ground water zones can provide significant information on water and contaminant movement. This paper presents information about perched ground water obtained from drilling and monitoring at a hazardous and radioactive waste disposal site at the Idaho National Engineering Laboratory. Six of forty-five wells drilled at the Radioactive Waste Management Complex have detected perched water in basalts above sedimentary interbeds. This paper describes the distribution and characteristics of perched ground water. It discusses perched water below the surficial sediments in wells at the RWMC, the characteristics of chemical constituents found in perched water, the implications for contaminant transport in the unsaturated zone of water, and the lateral extent of perched water. Recommendations are made to increase the probability of detecting and sampling low yield perched water zones. 6 refs., 6 figs., 2 tabs

  16. Development of a bio-inspired UAV perching system

    Science.gov (United States)

    Xie, Pu

    Although technologies of unmanned aerial vehicles (UAVs) including micro air vehicles (MAVs) have been greatly advanced in the recent years, it is still very difficult for a UAV to perform some very challenging tasks such as perching to any desired spot reliably and agilely like a bird. Unlike the UAVs, the biological control mechanism of birds has been optimized through millions of year evolution and hence, they can perform many extremely maneuverability tasks, such as perching or grasping accurately and robustly. Therefore, we have good reason to learn from the nature in order to significantly improve the capabilities of UAVs. The development of a UAV perching system is becoming feasible, especially after a lot of research contributions in ornithology which involve the analysis of the bird's functionalities. Meanwhile, as technology advances in many engineering fields, such as airframes, propulsion, sensors, batteries, micro-electromechanical-system (MEMS), and UAV technology is also advancing rapidly. All of these research efforts in ornithology and the fast growing development technologies in UAV applications are motivating further interests and development in the area of UAV perching and grasping research. During the last decade, the research contributions about UAV perching and grasping were mainly based on fixed-wing, flapping-wing, and rotorcraft UAVs. However, most of the current researches in UAV systems with perching and grasping capability are focusing on either active (powered) grasping and perching or passive (unpowered) perching. Although birds do have both active and passive perching capabilities depending on their needs, there is no UAV perching system with both capabilities. In this project, we focused on filling this gap. Inspired by the anatomy analysis of bird legs and feet, a novel perching system has been developed to implement the bionics action for both active grasping and passive perching. In addition, for developing a robust and

  17. Application of fractional factorial design to improve hot smoked Nile Perch (Lates niloticus quality

    Directory of Open Access Journals (Sweden)

    Sokamté, T.A.

    2017-06-01

    Full Text Available The aim of this research was to study the parameters influencing moisture, salt and total phenol content of hot smoked Nile Perch and to compare the influence of processing conditions on its proximate composition and sensory quality. The effect on moisture, salt and total phenol content was investigated using fractional factorial design with seven factors and two levels: X1 for brine concentration, X2 for brining time, X3 for preliminary smoking-drying time, X4 for smoking time, X5 for hot smoking time, X6 for smoking temperature and X7 for hot smoking temperature. A Multiple Linear Regression Analysis was performed to fit the mathematical model to the collected data and the model tested using analysis of variance (ANOVA. Results of ANOVA indicated the good accuracy and highest significance of the mathematical model. The range of total protein and lipid content was 17.96 to 34.34% and 0.87 to 4.43%, respectively. The range of general acceptability of smoked Nile Perch was 4.6 to 8.2 based on 9-point hedonic scale. Based on the results obtained, including the overall acceptability, proximate composition and smoking criteria of finished product, samples produced with the following conditions: brining at 4% for 270min, drying at 30°C for 30min and the smoked time/temperature cycles following: 30°C/120min; 50°C/240min and 80°C/240min was the best and most accepted. The results derived from this study indicate that the fractional factorial design is a useful screening tool for improving industrial smoking process of Nile Perch.

  18. Perched-Water Evaluation for the Deep Vadose Zone Beneath the B, BX, and BY Tank Farms Area of the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Oostrom, Martinus; Carroll, KC; Chronister, Glen B.

    2013-06-28

    Perched-water conditions have been observed in the vadose zone above a fine-grained zone that is located a few meters above the water table within the B, BX, and BY Tank Farms area. The perched water contains elevated concentrations of uranium and technetium-99. This perched-water zone is important to consider in evaluating the future flux of contaminated water into the groundwater. The study described in this report was conducted to examine the perched-water conditions and quantitatively evaluate 1) factors that control perching behavior, 2) contaminant flux toward groundwater, and 3) associated groundwater impact.

  19. The Effects of Zebra Mussels (Dreissena polymorpha) on the Foraging Success of Eurasian Perch (Perca fluviatilis) and Ruffe (Gymnocephalus cernuus)

    Science.gov (United States)

    Dieterich, Axel; Mörtl, Martin; Eckmann, Reiner

    2004-07-01

    Complex habitat structures can influence the foraging success of fish. Competition for food between fish species can therefore depend on the competitors' abilities to cope with structural complexity. In laboratory experiments, we comparatively assessed effects of zebra mussels (Dreissena polymorpha Pall.) on the foraging success of Eurasian perch (Perca fluviatilis L.) and ruffe (Gymnocephalus cernuus (L.)). In single-species and mixed-species experiments, the fish were fed caddisfly larvae (Tinodes waeneri (L.)) over complex (mussel-covered stones) and less-complex (bare stones) substrates. With intraspecific competition, food consumption by perch and ruffe decreased significantly when the complex substrate was used. With interspecific competition, food consumption by perch and ruffe did not change with substrate complexity, but perch clearly out-competed ruffe on both substrates. Zebra mussel beds provide a refuge for macrozoobenthos against predation by ruffe and probably also by perch. (

  20. Food habits of stunted and non-stunted white perch (Morone americana)

    Science.gov (United States)

    Gosch, N.J.C.; Stittie, J.R.; Pope, K.L.

    2010-01-01

    We studied food habits of white perch (Morone americana) from two populations with different stable states (stunted [Branched Oak Lake, Nebraska] and nonstunted [Pawnee Lake, Nebraska]) to determine if change in food habits of white perch is likely to occur in situations where a stunted white perch population is altered to a nonstunted state and vice versa. Three approaches were used to quantitatively describe seasonal (spring = March-May, summer = June-August, autumn = September-November) diets of white perch - 1) frequency of occurrence, 2) percentage of composition by volume, and 3) mean stomach fullness. White perch diets were dominated by cladocerans and dipterans in both reservoirs during all seasons. Fish egg predation was similar between reservoirs, and white perch rarely consumed fishes in either the stunted or the non-stunted population. Shifting a white perch population between stunted and non-stunted states will likely cause little or no change in food habits; fish in both states will primarily consume invertebrates.

  1. The Effect of Cooled Perches on Immunological Parameters of Caged White Leghorn Hens during the Hot Summer Months.

    Directory of Open Access Journals (Sweden)

    Rebecca A Strong

    Full Text Available The objective of this study was to determine if thermally cooled perches improve hen immunity during hot summer. White Leghorn pullets at 16 week of age were randomly assigned to 18 cages of 3 banks at 9 hens per cage. Each bank was assigned to 1 of the 3 treatments up to 32 week of age: 1 thermally cooled perches, 2 perches with ambient air, and 3 cages without perches. Hens were exposed to natural ambient temperatures from June through September 2013 in Indiana with a 4 h acute heat episode at 27.6 week of age. The packed cell volume, heterophil to lymphocyte (H/L ratio, plasma concentrations of total IgG, and cytokines of interleukin-1β and interleukin-6, plus lipopolysaccharide-induced tumor necrosis factorfactor were measured at both 27.6 and 32 week of age. The mRNA expressions of these cytokines, toll-like receptor-4, and inducible nitric oxide synthase were also examined in the spleen of 32 week-old hens. Except for H/L ratio, thermally cooled perches did not significantly improve currently measured immunological indicators. These results indicated that the ambient temperature of 2013 summer in Indiana (24°C, 17.1 to 33.1°C was not high enough and the 4 h heat episode at 33.3°C (32 to 34.6°C was insufficient in length to evoke severe heat stress in hens. However, cooled perch hens had a lower H/L ratio than both air perch hens and control hens at 27.6 week of age and it was still lower compared to control hens (P < 0.05, respectively at 32 week of age. The lowered H/L ratio of cooled perch hens may suggest that they were able to cope with acute heat stress more effectively than control hens. Further studies are needed to evaluate the effectiveness of thermally cooled perches on hen health under higher ambient temperatures.

  2. Population morphological variation of the Nile perch (Lates niloticus ...

    African Journals Online (AJOL)

    use

    The analysis clustered the Nile perch into two groups, which were found to be as characterised by earlier morphological description of this species and most probably are representatives of two distinct ... species of Lates niloticus as the specimens from Lakes ... (K), which is one factor that is considered when determining the ...

  3. Comparative perch selection in Southern Fiscal Lanius collaris and ...

    African Journals Online (AJOL)

    Here we tested for evidence of competition for perch space. ... is a product of different perch preferences, territoriality and the local plant community. Keywords: competition, interspecific territorial aggression, niche partitioning, sympatry ...

  4. Feeding under predation risk: potential sex-specific response of perch (Perca fluviatilis).

    Czech Academy of Sciences Publication Activity Database

    Estlander, Satu; Nurminen, L.

    2014-01-01

    Roč. 23, č. 3 (2014), s. 478-480 ISSN 0906-6691 Institutional support: RVO:60077344 Keywords : foraging * sexual size dimorphism * predation * perch * pike Subject RIV: EH - Ecology, Behaviour Impact factor: 1.701, year: 2014

  5. Fish protein fingerprint in whole muscle samples of yellow perch ...

    African Journals Online (AJOL)

    Many studies have shown the impact of environmental and/or genetic factors on the growth and development of various fish species. However, the role of genes supporting the cellular and molecular mechanisms responsible for fish was to compare whole muscle proteomic profiles of large versus small growth yellow perch ...

  6. The first isolation of a rhabdovirus from perch (Perca fluviatilis) in Norway

    DEFF Research Database (Denmark)

    Dannevig, B.H.; Olesen, Niels Jørgen; Jentoft, S.

    2001-01-01

    was stained in IF with rabbit antisera against perch rhabdovirus, pike rhabdovirus and lake trout rhabdovirus and neutralised by anti perch rhabdovirus indicating. that the Norwegian perch virus is closely related to these viruses belonging to the Vesiculovirus genus of the family Rhabdoviridae...

  7. The first isolation of a rhabdovirus from perch (Perca fluviatilis) in Norway

    DEFF Research Database (Denmark)

    Dannevig, B.H.; Olesen, Niels Jørgen; Jentoft, S.

    2001-01-01

    was stained in IF with rabbit antisera against perch rhabdovirus, pike rhabdovirus and lake trout rhabdovirus and neutralised by anti perch rhabdovirus indicating that the Norwegian perch virus is closely related to these viruses belonging to the Vesiculovirus genus of the family Rhabdoviridae...

  8. Sex-dependent responses of perch to changes in water clarity and temperature

    Czech Academy of Sciences Publication Activity Database

    Estlander, Satu; Nurminen, L.; Mrkvička, Tomáš; Olin, M.; Rask, M.; Lehtonen, H.

    2015-01-01

    Roč. 24, č. 4 (2015), s. 544-552 ISSN 0906-6691 Institutional support: RVO:60077344 Keywords : increasing water colour * climate change * European perch * feeding efficiency * sexual size dimorphism Subject RIV: EH - Ecology, Behaviour Impact factor: 2.052, year: 2015

  9. Domestication drive the changes of immune and digestive system of Eurasian perch (Perca fluviatilis).

    Science.gov (United States)

    Chen, Xiaowen; Wang, Jun; Qian, Long; Gaughan, Sarah; Xiang, Wei; Ai, Tao; Fan, Zhenming; Wang, Chenghui

    2017-01-01

    Domestication has altered a variety of traits within the Eurasian perch (Perca fluviatilis), including phenotypic, physiological and behavioral traits of Eurasian perch (Perca fluviatilis). Little is known, however, about the genetic changes between domesticated and wild Eurasian perch. In this study, we assembled a high-quality de novo reference transcriptome and identified differentially expressed genes between wild and domesticated Eurasian perch. A total of 113,709 transcripts were assembled, and 58,380 transcripts were annotated. Transcriptomic comparison revealed 630 differentially expressed genes between domesticated and wild Eurasian perch. Within domesticated Eurasian perch there were 412 genes that were up-regulated including MHCI, MHCII, chia, ighm within immune system development. There were 218 genes including try1, ctrl, ctrb, cela3b, cpa1 and cpb1, which were down-regulated that were associated with digestive processes. Our results indicated domestication drives the changes of immune and digestive system of Eurasian perch. Our study not only provide valuable genetic resources for further studies in Eurasian perch, but also provide novel insights into the genetic basis of physiological changes in Eurasian perch during domestication process.

  10. Impact of different colours of artificial light at night on melatonin rhythm and gene expression of gonadotropins in European perch.

    Science.gov (United States)

    Brüning, Anika; Hölker, Franz; Franke, Steffen; Kleiner, Wibke; Kloas, Werner

    2016-02-01

    The distribution and intensity of artificial light at night, commonly referred to as light pollution, is consequently rising and progressively also ecological implications come to light. Low intensity light is known to suppress nocturnal melatonin production in several fish species. This study aims to examine the least suppressive light colour for melatonin excreted into the holding water and the influence of different light qualities and quantities in the night on gene expression of gonadotropins in fish. European perch (Perca fluviatilis) were exposed to light of different wavelengths during the night (blue, green, and red). Melatonin concentrations were measured from water samples every 3h during a 24h period. Gene expression of gonadotropins was measured in perch exposed to different light colours and was additionally examined for perch subjected to different intensities of white light (0 lx, 1 lx, 10 lx, 100 lx) during the night. All different light colours caused a significant drop of melatonin concentration; however, blue light was least suppressive. Gene expression of gonadotropins was not influenced by nocturnal light of different light colours, but in female perch gonadotropin expression was significantly reduced by white light already at the lowest level (1 lx). We conclude that artificial light with shorter wavelengths at night is less effective in disturbing biological rhythms of perch than longer wavelengths, coinciding with the light situation in freshwater habitats inhabited by perch. Different light colours in the night showed no significant effect on gonadotropin expression, but white light in the night can disturb reproductive traits already at very low light intensities. These findings indicate that light pollution has not only the potential to disturb the melatonin cycle but also the reproductive rhythm and may therefore have implications on whole species communities. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Impact of impingement on the Hudson River white perch population. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barnthouse, L.W.; Van Winkle, W.; Kirk, B.L.; Vaughan, D.S.

    1982-02-01

    This report summarizes a series of analyses of the magnitude and biological significance of the impingement of white perch at the Indian Point Nuclear Generating Station and other Hudson River power plants. Included in these analyses were evaluations of: (1) two independent lines of evidence relating to the magnitude of impingement impacts on the Hudson River white perch population; (2) the additional impact caused by entrainment of white perch; (3) data relating to density-dependent growth among young-of-the-year white perch; (4) the feasibility of performing population-level analyses of impingement impacts on the white perch populations of Chesapeake Bay and the Delaware River; and (5) the feasibility of using simple food chain and food web models to evaluate community-level effects of impingement and entrainment. Estimated reductions in the abundances of the 1974 and 1975 white perch year classes, caused by impingement and entrainment, were high enough that the possibility of adverse long-term effects cannot be excluded.

  12. Effects of perch on feed consumption and behaviour of caged laying hens

    OpenAIRE

    E. VALKONEN; R. RINNE; J. VALAJA

    2008-01-01

    This experiment studied the effects of perches in furnished cages on behaviour and feed consumption of laying hens. The study used 352 Lohmann Selected Leghorn (LSL) hens. The hens were housed at 16 weeks of age in furnished cages in groups of 8 birds. The experiment lasted for 205 days. The treatments were: perches present from 16 weeks of age (P16), perches present from 19 weeks of age (P19), and no perches present (NP). Feed consumption and egg production were measured over the pre-laying ...

  13. Precision of four otolith techniques for estimating age of white perch from a thermally altered reservoir

    Science.gov (United States)

    Snow, Richard A.; Porta, Michael J.; Long, James M.

    2018-01-01

    The White Perch Morone americana is an invasive species in many Midwestern states and is widely distributed in reservoir systems, yet little is known about the species' age structure and population dynamics. White Perch were first observed in Sooner Reservoir, a thermally altered cooling reservoir in Oklahoma, by the Oklahoma Department of Wildlife Conservation in 2006. It is unknown how thermally altered systems like Sooner Reservoir may affect the precision of White Perch age estimates. Previous studies have found that age structures from Largemouth Bass Micropterus salmoides and Bluegills Lepomis macrochirus from thermally altered reservoirs had false annuli, which increased error when estimating ages. Our objective was to quantify the precision of White Perch age estimates using four sagittal otolith preparation techniques (whole, broken, browned, and stained). Because Sooner Reservoir is thermally altered, we also wanted to identify the best month to collect a White Perch age sample based on aging precision. Ages of 569 White Perch (20–308 mm TL) were estimated using the four techniques. Age estimates from broken, stained, and browned otoliths ranged from 0 to 8 years; whole‐view otolith age estimates ranged from 0 to 7 years. The lowest mean coefficient of variation (CV) was obtained using broken otoliths, whereas the highest CV was observed using browned otoliths. July was the most precise month (lowest mean CV) for estimating age of White Perch, whereas April was the least precise month (highest mean CV). These results underscore the importance of knowing the best method to prepare otoliths for achieving the most precise age estimates and the best time of year to obtain those samples, as these factors may affect other estimates of population dynamics.

  14. Cooled perch effects on performance and well-being traits in caged White Leghorn hens.

    Science.gov (United States)

    Hu, J Y; Hester, P Y; Makagon, M M; Vezzoli, G; Gates, R S; Xiong, Y J; Cheng, H W

    2016-12-01

    We assessed the effects of chilled water cooling perches on hen performance and physiological and behavioral parameters under "natural" high temperatures during the 2013 summer with a 4-hour acute heating episode. White Leghorns at 16 wk of age (N = 162) were randomly assigned to 18 cages (n = 9) arranged into 3 units. Each unit was assigned to one of the 3 treatments through 32 wk of age: 1) cooled perches, 2) air perches, and 3) no perches. Chilled water (10°C) was circulated through the cooled perches when cage ambient temperature exceeded 25°C. At the age of 27.6 wk, hens were subjected to a 4-hour acute heating episode of 33.3°C and plasma corticosterone was determined within 2 hours. Egg production was recorded daily. Feed intake and egg and shell quality were measured at 5-week intervals. Feather condition, foot health, adrenal and liver weights, plasma corticosterone, and heat shock protein 70 mRNA were determined at the end of the study at 32 wk of age. The proportion of hens per cage perching, feeding, drinking, panting, and wing spreading was evaluated over one d every 5 wks and on the d of acute heat stress. There were no treatment effects on the measured physiological and production traits except for nail length. Nails were shorter for cooled perch hens than control (P = 0.002) but not air perch hens. Panting and wing spread were observed only on the day of acute heat stress. The onset of both behaviors was delayed for cooled perch hens, and they perched more than air perch hens following acute heat stress (P = 0.001) and at the age 21.4 wk (P = 0.023). Cooled perch hens drank less than control (P = 0.019) but not air perch hens at the age 21.4 wk. These results indicate that thermally cooled perches reduced thermoregulatory behaviors during acute heat stress, but did not affect their performance and physiological parameters under the ambient temperature imposed during this study. Published by Oxford University Press on behalf of

  15. The acute toxicity of the metaldehyde on the climbing perch

    Science.gov (United States)

    Wahida Mohamad Ismail, Syamimi; Aini Dahalan, Farrah; Zakaria, Ammar; Mad Shakaff, Ali Yeon; Aqlima Ahmad, Siti; Shukor, Mohd Yunus Abd; Khalizan Sabullah, Mohd; Khalil, Khalilah Abdul; Jalil, Mohd Faizal Ab

    2018-03-01

    In Asia, Climbing perch (Anabas testudineus) is commonly found in paddy fields and irrigation systems. Due to its habitat, Climbing perch is exposed to toxic pesticides used in paddy fields such as metaldehyde which is one of the most widely used molluscicide. This study aims to determine the acute toxicity Lethal Concentration50 (LC50) of metaldehyde and its effect on the behaviour and physical changes of the Climbing perch. The fish mortality responses to six different metaldehyde concentrations ranging from 180 to 330 mg/L were investigated. The 96-h LC50 values were determined and analysed using three different analysis methods which is arithmetic, logarithmic and probit graphic. The LC50 values obtained in this study were 239, 234 and 232 mg/L, respectively. After 96-h of exposure to metaldehyde, the fish showed a series of abnormal behavioural response in all cases: imbalance position, and restlessness of movement. The LC50 values show that metaldehyde is moderately toxic to the Climbing perch indicating that metaldehyde is not destructive to Climbing perch. However, long term exposure of aquatic organisms to the metaldehyde means a continuous health risk for the fish population as they are more vulnerable and it is on high risk for human to consume this toxicated fishes.

  16. Food selectivity of perch (Perca fluviatilis L. ) in acidified lakes on the west coast of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, B

    1972-01-01

    The objective of the present paper was to examine presumed changes in the food composition of perch in lakes subjected to recent acidification, which emanates from sulfuric acid in the precipitation. The material analyzed (825 preserved specimens from 49 different lakes) was collected by the Fishery Board. These lakes represent a great variability in terms of pH. The perch were divided into four size groups and the stomach contents of each specimen was analyzed qualitatively and quantitatively. The results indicate that fish, which make up the bulk of food for adult perch, are replaced by various invertebrates at a decreasing pH. With a moderate decrease the water hog-louse (Asellus aquaticus) appears of major importance, whereas its place is taken by Corixa bugs in the most acidified lakes. These latter invertebrates are normally absent in the food of adult perch. Also, plankton accounts for a substantial share of the stomach contents. The reasons for these changes are manifold, but two factors are primarily discussed in this paper, viz. the effect of the acidification on the prey populations and the elimination of certain species by selective predation in a normal lake.

  17. Design of nest access grids and perches in front of the nests: Influence on the behavior of laying hens.

    Science.gov (United States)

    Stämpfli, K; Buchwalder, T; Fröhlich, E K F; Roth, B A

    2013-04-01

    In aviary systems for laying hens, it is important to provide suitable nest access platforms in front of the nests, allowing hens to reach and explore each of the nests easily. This access platform is needed to achieve good nest acceptance by the hens and thereby prevent mislaid eggs. In the present experiment, the behavior of hens using 2 different nest access platforms, a plastic grid and 2 wooden perches, was examined. Furthermore, the nests were placed on both sides of the aviary rack (corridor side and outdoor side), either integrated into the aviary rack itself (integrated nest; IN) or placed on the walls of the pens (wall nest; WN), resulting in a 2 × 2 factorial design Four thousand five hundred white laying hens were housed in 20 test pens. The eggs in the nests and mislaid eggs were collected daily, and the behavior of hens on the nest accesses was filmed during wk 25 and 26, using focal observation and scan sampling methods. More balancing, body contact, and agonistic interactions were expected for nests with perches, whereas more walking and nest inspections were expected for nests with grids. There were more mislaid eggs and balancing found in pens equipped with nests with wooden perches. More agonistic interactions and balancing, less standing, and a longer duration of nest inspection were found with the WN compared with the IN. Interactions between platform design and position of the nests were found for duration of nest visits, body contact, and walking, with the highest amount for WN equipped with plastic grids. Nests on the corridor side were favored by the hens. Nest-related behaviors, such as nest inspection, standing, and walking, decreased over time as did the number of hens on the nest accesses, whereas sitting increased. These results indicate that the hens had more difficulties in gripping the perches as designed. The lower number of hens on the nest access platforms in front of IN may be due to a better distribution around nests and tier

  18. Genetic diversity of perch rhabdoviruses isolates based on the nucleoprotein and glycoprotein genes.

    Science.gov (United States)

    Talbi, Chiraz; Cabon, Joelle; Baud, Marine; Bourjaily, Maya; de Boisséson, Claire; Castric, Jeannette; Bigarré, Laurent

    2011-12-01

    Despite the increasing impact of rhabdoviruses in European percid farming, the diversity of the viral populations is still poorly investigated. To address this issue, we sequenced the partial nucleoprotein (N) and complete glycoprotein (G) genes of nine rhabdoviruses isolated from perch (Perca fluviatilis) between 1999 and 2010, mostly from France, and analyzed six of them by immunofluorescence antibody test (IFAT). Using two rabbit antisera raised against either the reference perch rhabdovirus (PRhV) isolated in 1980 or the perch isolate R6146, two serogroups were distinguished. Meanwhile, based on partial N and complete G gene analysis, perch rhabdoviruses were divided into four genogroups, A-B-D and E, with a maximum of 32.9% divergence (G gene) between isolates. A comparison of the G amino acid sequences of isolates from the two identified serogroups revealed several variable regions that might account for antigenic differences. Comparative analysis of perch isolates with other rhabdoviruses isolated from black bass, pike-perch and pike showed some strong phylogenetic relationships, suggesting cross-host transmission. Similarly, striking genetic similarities were shown between perch rhabdoviruses and isolates from other European countries and various ecological niches, most likely reflecting the circulation of viruses through fish trade as well as putative transfers from marine to freshwater fish. Phylogenetic relationships of the newly characterized viruses were also determined within the family Rhabdoviridae. The analysis revealed a genetic cluster containing only fish viruses, including all rhabdoviruses from perch, as well as siniperca chuatsi rhabdovirus (SCRV) and eel virus X (EVEX). This cluster was distinct from the one represented by spring viraemia of carp vesiculovirus (SVCV), pike fry rhabdovirus (PFRV) and mammalian vesiculoviruses. The new genetic data provided in the present study shed light on the diversity of rhabdoviruses infecting perch in

  19. Demonstrations of bio-inspired perching landing gear for UAVs

    Science.gov (United States)

    Tieu, Mindy; Michael, Duncan M.; Pflueger, Jeffery B.; Sethi, Manik S.; Shimazu, Kelli N.; Anthony, Tatiana M.; Lee, Christopher L.

    2016-04-01

    Results are presented which demonstrate the feasibility and performance of two concepts of biologically-inspired landing-gear systems that enable bird-sized, unmanned aerial vehicles (UAV's) to land, perch, and take-off from branchlike structures and/or ledges. The first concept follows the anatomy of birds that can grasp ahold of a branch and perch as tendons in their legs are tensioned. This design involves a gravity-activated, cable-driven, underactuated, graspingfoot mechanism. As the UAV lands, its weight collapses a four-bar linkage pulling a cable which curls two opposing, multi-segmented feet to grasp the landing target. Each foot is a single, compliant mechanism fabricated by simultaneouly 3D-printing a flexible thermo-plastic and a stiffer ABS plastic. The design is optimized to grasp structures over a range of shapes and sizes. Quasi-static and flight tests of this landing gear affixed to RC rotorcraft (24 cm to 550 cm in diameter) demonstrate that the aircraft can land, perch, and take-off from a tree branch, rectangular wood board, PVC pipe, metal hand rail, chair armrest, and in addition, a stone wall ledge. Stability tests show that perching is maintained under base and wind disturbances. The second design concept, inspired by roosting bats, is a two-material, 3D-printed hooking mechanism that enables the UAV to stably suspend itself from a wire or small-diameter branch. The design balances structural stiffness for support and flexibility for the perching process. A flight-test demonstrates the attaching and dis-engaging of a small, RC quadcopter from a suspended line.

  20. Nutritional composition and shelflife of the lake victoria nile perch ...

    African Journals Online (AJOL)

    Nile perch, the most important commercial fish species from the Lake Victoria fishery, contributes about 67% of Kenya's total annual fish export earnings. Despite the Nile perch being an important foreign exchange earner, little information is available on its nutritional composition and shelf life on ice, information that is ...

  1. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Blazer, Vicki S., E-mail: Vblazer@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Pinkney, Alfred E., E-mail: Fred_Pinkeny@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Jenkins, Jill A., E-mail: jenkinsj@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Iwanowicz, Luke R., E-mail: Liwanowicz@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Minkkinen, Steven, E-mail: steve_minkkinen@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Draugelis-Dale, Rassa O., E-mail: daler@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Uphoff, James H., E-mail: juphoff@dnr.state.md.us [Maryland Department of Natural Resources, Fisheries Service, Cooperative Oxford Laboratory, 904 South Morris Street, Oxford, MD 21654 (United States)

    2013-03-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. - Highlights: ► Reduced recruitment of yellow perch has occurred in urban tributaries of Chesapeake Bay. ► We compared reproductive health biomarkers in perch from two urban, one developing, two less developed

  2. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

    International Nuclear Information System (INIS)

    Blazer, Vicki S.; Pinkney, Alfred E.; Jenkins, Jill A.; Iwanowicz, Luke R.; Minkkinen, Steven; Draugelis-Dale, Rassa O.; Uphoff, James H.

    2013-01-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. - Highlights: ► Reduced recruitment of yellow perch has occurred in urban tributaries of Chesapeake Bay. ► We compared reproductive health biomarkers in perch from two urban, one developing, two less developed watersheds.

  3. Perched aquifers - their potential impact on contaminant transport in the southern High Plains, Texas

    International Nuclear Information System (INIS)

    Mullican, W.F. III; Fryar, A.E.; Johns, N.D.

    1993-01-01

    Understanding the hydrogeology and hydrochemistry of perched aquifers at potential and known contaminated waste sites has become increasingly important because of the impact these aquifers may have on contaminant transport independent of regional aquifer processes. Investigations of a perched aquifer above the Ogallala aquifer are being conducted in the region of the U.S. Department of Energy's Pantex Plant, a proposed Superfund site, located approximately 20 mi northeast of Amarillo, Texas. Since the early 1950s, a small playa basin located on the Pantex Plant has been used as a waste-water discharge pond with daily discharge rates ranging from 400,000 to 1 million gal. The focus of this investigation is an unconfined, perched aquifer that overlies a thick silty clay sequence within the upper, mostly unsaturated part of the Ogallala Formation (Neogene). In the area of the Pantex Plant, measured depths to the perched aquifer range from 200 to 300 ft below land surface, whereas depth to the regional Ogallala aquifer ranges from 375 to 500 ft. The potentiometric surface of the perched aquifer typically represents groundwater mounds proximal to the playas and thins into trough in the interplaya areas. Hydrologic gradients of the primary mound under investigation are relatively high, ranging from 28 to 45 ft/mi. Calculated transmissivities have a geometric mean of 54 ft 2 /day, with saturated thicknesses ranging from 4 to 1000 ft. Modeling of the perched aquifer was designed to determine how much, if any, discharge to the small playa basin has enhanced recharge to the perched aquifers and increased the vertical and lateral extent of the perched aquifer. Preliminary results indicate that measurements of vertical conductance through the perching silty-clay sequence and recharge rates through playas are critical for calibrating the model. Accurate delineation of rates and flow directions in the perched aquifer is critical to any successful remediation effort

  4. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

    Science.gov (United States)

    Blazer, Vicki; Pinkney, Alfred E.; Jenkins, Jill A.; Iwanowicz, Luke R.; Minkkinen, Steven; Draugelis-Dale, Rassa O.; Uphoff, James H.

    2013-01-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed.

  5. Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay.

    Science.gov (United States)

    Blazer, Vicki S; Pinkney, Alfred E; Jenkins, Jill A; Iwanowicz, Luke R; Minkkinen, Steven; Draugelis-Dale, Rassa O; Uphoff, James H

    2013-03-01

    Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007-2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. Published by Elsevier B.V.

  6. Woody structure facilitates invasion of woody plants by providing perches for birds.

    Science.gov (United States)

    Prather, Chelse M; Huynh, Andrew; Pennings, Steven C

    2017-10-01

    Woody encroachment threatens prairie ecosystems globally, and thus understanding the mechanisms that facilitate woody encroachment is of critical importance. Coastal tallgrass prairies along the Gulf Coast of the US are currently threatened by the spread of several species of woody plants. We studied a coastal tallgrass prairie in Texas, USA, to determine if existing woody structure increased the supply of seeds from woody plants via dispersal by birds. Specifically, we determined if (i) more seedlings of an invasive tree ( Tridacia sebifera ) are present surrounding a native woody plant ( Myrica cerifera ); (ii) wooden perches increase the quantity of seeds dispersed to a grassland; and (iii) perches alter the composition of the seed rain seasonally in prairie habitats with differing amounts of native and invasive woody vegetation, both underneath and away from artificial wooden perches. More T. sebifera seedlings were found within M. cerifera patches than in graminoid-dominated areas. Although perches did not affect the total number of seeds, perches changed the composition of seed rain to be less dominated by grasses and forbs. Specifically, 20-30 times as many seeds of two invasive species of woody plants were found underneath perches independent of background vegetation, especially during months when seed rain was highest. These results suggest that existing woody structure in a grassland can promote further woody encroachment by enhancing seed dispersal by birds. This finding argues for management to reduce woody plant abundance before exotic plants set seeds and argues against the use of artificial perches as a restoration technique in grasslands threatened by woody species.

  7. First isolation of a rhabdovirus from perch Perca fluviatilis in Switzerland.

    Science.gov (United States)

    Wahli, Thomas; Bellec, Laure; von Siebenthal, Beat; Cabon, Joëlle; Schmidt-Posthaus, Heike; Morin, Thierry

    2015-10-16

    Perca fluviatilis is a fish species of increasing interest to the Swiss fish farming industry. In recent years, recirculation systems have been specifically set up to increase production. In one of these farms, abnormal spiral swimming associated with elevated mortalities occurred in repeated batches of imported perch shortly after stocking on several occasions. No bacterial or parasitic etiology was detected, but a virus grown in bluegill fry (BF-2) cells was identified as perch rhabdovirus. Subsequent investigations of other samples suggested a viral tropism for the central nervous system (CNS). Phylogenetic analysis of the partial N and entire G gene sequences positioned this isolate in genogroup C of the species Perch rhabdovirus, with high nucleotide and amino acid (aa) sequence identities with the DK5533 strain isolated in Denmark in 1989. Comparative studies using other closely related isolates allowed the distinction of 2 serological patterns among perch rhabdoviruses and the identification of a proline substitution by a serine in position 147 of the glycoprotein potentially involved in antigenic differentiation. Even if perch imported onto the farm tested negative by virus isolation prior to transport, they may have been the origin of this outbreak since CNS tissue was not included in the samples that were analyzed. Another possibility might be a sub-clinical infection with a viral load in resident fish too low to be detected. This study reports the first isolation of a perch rhabdovirus in Switzerland, and emphasizes the necessity of optimizing diagnostic tools that facilitate better control of the risks associated with fish translocation.

  8. Water transparency drives intra-population divergence in Eurasian Perch (Perca fluviatilis).

    Science.gov (United States)

    Bartels, Pia; Hirsch, Philipp E; Svanbäck, Richard; Eklöv, Peter

    2012-01-01

    Trait combinations that lead to a higher efficiency in resource utilization are important drivers of divergent natural selection and adaptive radiation. However, variation in environmental features might constrain foraging in complex ways and therefore impede the exploitation of critical resources. We tested the effect of water transparency on intra-population divergence in morphology of Eurasian perch (Perca fluviatilis) across seven lakes in central Sweden. Morphological divergence between near-shore littoral and open-water pelagic perch substantially increased with increasing water transparency. Reliance on littoral resources increased strongly with increasing water transparency in littoral populations, whereas littoral reliance was not affected by water transparency in pelagic populations. Despite the similar reliance on pelagic resources in pelagic populations along the water transparency gradient, the utilization of particular pelagic prey items differed with variation in water transparency in pelagic populations. Pelagic perch utilized cladocerans in lakes with high water transparency and copepods in lakes with low water transparency. We suggest that under impaired visual conditions low utilization of littoral resources by littoral perch and utilization of evasive copepods by pelagic perch may lead to changes in morphology. Our findings indicate that visual conditions can affect population divergence in predator populations through their effects on resource utilization.

  9. Monitoring and sampling perched ground water in a basaltic terrain

    International Nuclear Information System (INIS)

    Hubbell, J.M.

    1990-01-01

    Perched ground water zones are often overlooked in monitoring plans, but they can provide significant information on water and contaminant movement. This paper presents information about perched ground water obtained from drilling and monitoring at a hazardous and radioactive waste disposal site at the Idaho National Engineering Laboratory. Six of forty-five wells drilled at the Radioactive Waste Management Complex have detected perched water in basalts above sedimentary interbeds. Perched water has been detected at depths of 90 and 210 ft below land surface, approximately 370 ft above the regional water table. Eighteen years of water level measurements from one well at a depth of 210 ft indicate a consistent source of water. Water level data indicate a seasonal fluctuation. The maximum water level in this well varies within a 0.5 ft interval, suggesting the water level reaches equilibrium with the inflow to the well at this height. Volatile organic constituents have been detected in concentrations from 1.2 to 1.4 mg/L of carbon tetrachloride. Eight other volatile organics have been detected. The concentrations of organics are consistent with the prevailing theory of movement by diffusion in the gaseous phase. Results of tritium analyses indicate water has moved to a depth of 86 ft in 17 yr. Results of well sampling analyses indicate monitoring and sampling of perched water can be a valuable resource for understanding the hydrogeologic environment of the vadose zone at disposal sites

  10. Letter Report: Stable Hydrogen and Oxygen Isotope Analysis of B-Complex Perched Water Samples

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Brady D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moran, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nims, Megan K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Saunders, Danielle L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-04-13

    Fine-grained sediments associated with the Cold Creek Unit at Hanford have caused the formation of a perched water aquifer in the deep vadose zone at the B Complex area, which includes waste sites in the 200-DV-1 Operable Unit and the single-shell tank farms in Waste Management Area B-BX-BY. High levels of contaminants, such as uranium, technetium-99, and nitrate, make this aquifer a continuing source of contamination for the groundwater located a few meters below the perched zone. Analysis of deuterium (2H) and 18-oxygen (18O) of nine perched water samples from three different wells was performed. Samples represent time points from hydraulic tests performed on the perched aquifer using the three wells. The isotope analyses showed that the perched water had δ2H and δ18O ratios consistent with the regional meteoric water line, indicating that local precipitation events at the Hanford site likely account for recharge of the perched water aquifer. Data from the isotope analysis can be used along with pumping and recovery data to help understand the perched water dynamics related to aquifer size and hydraulic control of the aquifer in the future.

  11. Susceptibility of Koi and Yellow Perch to infectious hematopoietic necrosis virus by experimental exposure

    Science.gov (United States)

    Palmer, Alexander D.; Emmenegger, Eveline J.

    2014-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a novirhabdoviral pathogen that originated in western North America among anadromous Pacific salmonids. Severe disease epidemics in the late 1970s resulting from IHNV's invasion into farmed Rainbow Trout Oncorhynchus mykiss in North America, Asia, and Europe emphasized IHNV's ability to adapt to new hosts under varying rearing conditions. Yellow Perch Perca flavescens and Koi Carp Cyprinus carpio (hereafter, “Koi”) are aquaculture-reared fish that are highly valued in sport fisheries and the ornamental fish trade, respectively, but it is unknown whether these fish species are vulnerable to IHNV infection. In this study, we exposed Yellow Perch, Koi, and steelhead (anadromous Rainbow Trout) to IHNV by intraperitoneal injection (106 PFU/fish) and by immersion (5.7×105 PFU/mL) for 7 h, and monitored fish for 28 d. The extended immersion exposure and high virus concentrations used in the challenges were to determine if the tested fish had any level of susceptibility. After experimental exposure, Yellow Perch and Koi experienced low mortality (35%). Virus was found in dead fish of all species tested and in surviving Yellow Perch by plaque assay and quantitative reverse transcription polymerase chain reaction (qPCR), with a higher prevalence in Yellow Perch than Koi. Infectious virus was also detected in Yellow Perch out to 5 d after bath challenge. These findings indicate that Yellow Perch and Koi are highly resistant to IHNV disease under the conditions tested, but Yellow Perch are susceptible to infection and may serve as possible virus carriers.

  12. Degradation of male and female rufous-and-white wren songs in a tropical forest: effects of sex, perch height, and habitat

    DEFF Research Database (Denmark)

    Barker, Nicole K.S.; Dabelsteen, Torben; Mennill, Daniel J.

    2009-01-01

    We performed a song transmission experiment to investigate the effects of distance, song post height, receiver perch height, signaller sex, and microhabitat on song degradation in rufous-and-white wrens (Thryothorus rufalbus), a neotropical duetting songbird. We quantified the effects of these fa......We performed a song transmission experiment to investigate the effects of distance, song post height, receiver perch height, signaller sex, and microhabitat on song degradation in rufous-and-white wrens (Thryothorus rufalbus), a neotropical duetting songbird. We quantified the effects...... of these factors on excess attenuation, signal-to-noise ratio, tail-to-signal ratio, and blur ratio of male and female songs. As expected, song degradation increased with distance between signaller and receiver. Songs transmitted best when emitted from moderate heights (5-7 m), although this pattern varied....... Rufous-and-white wren songs appeared more attenuated in open field than forest habitats, but microhabitat conditions within the forests exerted a strong influence on song degradation. These findings match previous studies showing an effect of distance, song post height, and habitat, but contrast...

  13. Physiological and ecological factors influencing the radiocaesium contamination of fish species from Kiev reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Koulikov, A.O. [A.N. Severtzov Institute of Evolutionary Morphology and Ecology of Animals, Russian Academy of Sciences, Moscow (Russian Federation)

    1995-11-23

    The monitoring of {sup 137}Cs contamination of fish from the northern part of the Kiev reservoir between 1987 and 1992 indicated systematic differences in the long-term average contamination levels of different species, which are closely related to their trophic levels. The average contamination of the predatory species: perch (Perca fluviatilis) and pike (Esox lucius) were roughly factors of 6.3 and 4.4 respectively, higher than those of the nonpredatory species: bream (Abramis brama), silver bream (Blicca bjoerkna) and rudd (Scardinius erythrophothalmus). For tench (Tinca tinca) and goldfish (Carassius sp.), this factor is 2. The solution of the caesium balance equation in fish obtained for equilibrium conditions, which is applicable to the long-term contamination, provides some explanations for these accumulation differences between the species with respect to influences by different ecological and physiological factors.

  14. Intraspecific variation in gill morphology of juvenile Nile perch, Lates niloticus, in Lake Nabugabo, Uganda

    Science.gov (United States)

    Paterson, Jaclyn A.; Chapman, Lauren J.; Schofield, Pamela J.

    2010-01-01

    Several studies have demonstrated intraspecific variation in fish gill size that relates to variation in dissolved oxygen (DO) availability across habitats. In Lake Nabugabo, East Africa, ecological change over the past 12 years has coincided with a shift in the distribution of introduced Nile perch such that a larger proportion of the population now inhabits waters in or near wetland ecotones where DO is lower than in open waters of the lake. In this study, we compared gill size of juvenile Nile perch between wetland and exposed (open-water) habitats of Lake Nabugabo in 2007, as well as between Nile perch collected in 1996 and 2007. For Nile perch of Lake Nabugabo [<20 cm total length (TL)], there was a significant habitat effect on some gill traits. In general, fish from wetland habitats were characterized by a longer total gill filament length and average gill filament length than conspecifics from exposed habitats. Nile perch collected from wetland areas in 2007 had significantly larger gills (total gill filament length) than Nile perch collected in 1996, but there was no difference detected between Nile perch collected from exposed sites in 2007 and conspecifics collected in 1996.

  15. Susceptibility of pike-perch Sander lucioperca to a panel of ranavirus isolates

    DEFF Research Database (Denmark)

    Jensen, Britt Bang; Holopainen, Riikka; Tapiovaara, Hannele

    2011-01-01

    The host range of ranaviruses was investigated by challenging pike-perch (Sander lucioperca) with the following ranavirus isolates: epizootic haematopoietic necrosis virus (EHNV), European sheatfish virus (ESV), European catfish virus (ECV), pike-perch iridovirus (PPIV), short-finned eel virus...

  16. INVESTIGATIONS ON TECHNOLOGICAL PARAMETERS IN INTENSIVE REARING OF PIKE-PERCH (STIZOSTEDION LUCIOPERCA

    Directory of Open Access Journals (Sweden)

    Tamás Molnár

    2000-06-01

    Full Text Available Market demands and competition force the production of high quality freshwater fish in European aquaculture. In Hungary pike-perch is the most „noble” and perhaps the most sensitive fish species. One of the constraints of the increasing its production in natural waters, reservoirs and ponds is the shortage in adequate sized alevins. The possible solution of this problem can be the elaboration of intensive rearing technics of pond prereared fry. The aims of the present work were to test the growing capacity, feed conversion and survival of pike-perch in intensive circumstances. Fish were kept in 130 l aquaria working in recirculation system at an average water temperature of 220.5 C. Two stocking densities were applied (18 and 36 fish/aquarium. Minced fish (test and live prey (control were offered twice a day till satiation in two replications. The experiment lasted 4 weeks. According to our results minced fish is suitable feed in the intensive rearing of pike-perch alevins. Daily food intake was only influenced significantly by different feeds (2.01g vs.4.53 g, test and control, respectively. Feeding and stocking density had significant effect (P=0.001 and 0.017 on the average weight gain (0.52 g and 1.40 g for minced fish and live feed, respectively, 1.02 g in lower and 0.90 g in higher density. Owning to the high variances treatment effect on feed conversion proved to be not significant. Average survival of the minced fish fed group was 62.2 % vs. 78.8 % of the live fish fed alevins. This difference was significant (P<0.01 in the first two weeks when almost all of the losses happened due to cannibalism and other unknown reasons. Based on our results a period of 10–14 days is needed for pre-reared pike-perch to change gradually their feeding from zooplankton to minced fish diet.

  17. Landscape features influence postrelease predation on endangered black-footed ferrets

    Science.gov (United States)

    Poessel, S.A.; Breck, S.W.; Biggins, D.E.; Livieri, T.M.; Crooks, K.R.; Angeloni, L.

    2011-01-01

    Predation can be a critical factor influencing recovery of endangered species. In most recovery efforts lethal and nonlethal influences of predators are not sufficiently understood to allow prediction of predation risk, despite its importance. We investigated whether landscape features could be used to model predation risk from coyotes (Canis latrans) and great horned owls (Bubo virginianus) on the endangered black-footed ferret (Mustela nigripes). We used location data of reintroduced ferrets from 3 sites in South Dakota to determine whether exposure to landscape features typically associated with predators affected survival of ferrets, and whether ferrets considered predation risk when choosing habitat near perches potentially used by owls or near linear features predicted to be used by coyotes. Exposure to areas near likely owl perches reduced ferret survival, but landscape features potentially associated with coyote movements had no appreciable effect on survival. Ferrets were located within 90 m of perches more than expected in 2 study sites that also had higher ferret mortality due to owl predation. Densities of potential coyote travel routes near ferret locations were no different than expected in all 3 sites. Repatriated ferrets might have selected resources based on factors other than predator avoidance. Considering an easily quantified landscape feature (i.e., owl perches) can enhance success of reintroduction efforts for ferrets. Nonetheless, development of predictive models of predation risk and management strategies to mitigate that risk is not necessarily straightforward for more generalist predators such as coyotes. ?? 2011 American Society of Mammalogists.

  18. 62 years of population dynamics of European perch (Perca fluviatilis) in a mesotrophic lake tracked using angler diaries: The role of commercial fishing, predation and temperature

    DEFF Research Database (Denmark)

    Skov, Christian; Jansen, Teunis; Arlinghaus, Robert

    2017-01-01

    (abundance, mean size and record size) of European perch (Perca fluviatilis L.) in relation to the impact of three commercial fishers with different fishing strategies, pike (Esox lucius L.) predation and temperature. We found that anglers’ harvest rates of perch varied by a factor of 10 over time......, but it also underlines the need for supplementary data on biotic and abiotic factors to reach the full potential of angler diary data...

  19. Sampling of deep benthic perch fry: insight into the diel vertical migrations.

    Czech Academy of Sciences Publication Activity Database

    Čech, Martin; Frouzová, Jaroslava; Peterka, Jiří; Jůza, Tomáš; Draštík, Vladislav; Vašek, Mojmír; Kubečka, Jan

    2017-01-01

    Roč. 784, č. 1 (2017), s. 1-8 ISSN 0018-8158 R&D Projects: GA ČR GA206/06/1371; GA ČR GP206/09/P266; GA MŠk(CZ) EE2.3.20.0204; GA MŠk(CZ) 7F14316 Institutional support: RVO:60077344 Keywords : bathypelagic perch fry * Breder trap * Fulton's condition factor * Perca fluviatilis * Římov Reservoir * SCUBA diving Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.056, year: 2016

  20. Combined effects of temperature changes and metal contamination at different levels of biological organization in yellow perch

    International Nuclear Information System (INIS)

    Grasset, Julie; Ollivier, Élodie; Bougas, Bérénice; Yannic, Glenn; Campbell, Peter G.C.; Bernatchez, Louis; Couture, Patrice

    2016-01-01

    Highlights: • Yellow perch were exposed to a combination of heat and metal (Cd or Ni) stress. • Kidney metal accumulation was greatly enhanced at higher temperatures. • Elevated temperatures negatively affected several indicators of condition and metabolic capacities. • Exposure to Ni stimulated gonad development. • Metal stress modified the normal response of antioxidant capacities and apoptosis to heat stress. - Abstract: In this study, we measured the effects of temperature (9 °C, 20 °C, and 28 °C), metal contamination (cadmium and nickel) and their interaction on yellow perch (Perca flavescens) using liver enzymatic and transcriptomic endpoints and biometric indices. Kidney metal concentrations increased with a rise of temperature. The biometric indices analysed (Fulton condition factor, pyloric cæca, hepatosomatic and gonadosomatic indices) generally decreased with an increase of temperature but not with metal contamination. At the enzymatic level, the activity of superoxide dismutase (SOD), involved in antioxidant response, was affected by both temperature and metal contamination, whereas the activity of glucose-6-phosphate dehydrogenase (G6PDH), involved in energy accumulation but also in antioxidant response, was only affected by metal exposure. The response of perch to the stressors at the transcriptional level differed from the metabolic response. In particular, the transcription level of the cco and g6pdh genes sharply decreased with increasing temperature, while the activities of the corresponding enzymes remained stable. The normal response of the transcription level of the apoptotic gene (diablo) to heat stress was also altered in metal-contaminated fish. The combination of metal and temperature stresses also modified the response of antioxidant metabolism induced by these stressors individually. This study contributes to a better understanding of the influences of natural stressors like temperature on biomarkers commonly used in

  1. Combined effects of temperature changes and metal contamination at different levels of biological organization in yellow perch

    Energy Technology Data Exchange (ETDEWEB)

    Grasset, Julie [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Ollivier, Élodie [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bougas, Bérénice [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Yannic, Glenn [Laboratoire d’Écologie Alpine, UMR CNRS 5553, Université de Savoie Mont Blanc, 73376 Le Bourget-du-lac (France); Campbell, Peter G.C. [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Bernatchez, Louis [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut National de la Recherche Scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada)

    2016-08-15

    Highlights: • Yellow perch were exposed to a combination of heat and metal (Cd or Ni) stress. • Kidney metal accumulation was greatly enhanced at higher temperatures. • Elevated temperatures negatively affected several indicators of condition and metabolic capacities. • Exposure to Ni stimulated gonad development. • Metal stress modified the normal response of antioxidant capacities and apoptosis to heat stress. - Abstract: In this study, we measured the effects of temperature (9 °C, 20 °C, and 28 °C), metal contamination (cadmium and nickel) and their interaction on yellow perch (Perca flavescens) using liver enzymatic and transcriptomic endpoints and biometric indices. Kidney metal concentrations increased with a rise of temperature. The biometric indices analysed (Fulton condition factor, pyloric cæca, hepatosomatic and gonadosomatic indices) generally decreased with an increase of temperature but not with metal contamination. At the enzymatic level, the activity of superoxide dismutase (SOD), involved in antioxidant response, was affected by both temperature and metal contamination, whereas the activity of glucose-6-phosphate dehydrogenase (G6PDH), involved in energy accumulation but also in antioxidant response, was only affected by metal exposure. The response of perch to the stressors at the transcriptional level differed from the metabolic response. In particular, the transcription level of the cco and g6pdh genes sharply decreased with increasing temperature, while the activities of the corresponding enzymes remained stable. The normal response of the transcription level of the apoptotic gene (diablo) to heat stress was also altered in metal-contaminated fish. The combination of metal and temperature stresses also modified the response of antioxidant metabolism induced by these stressors individually. This study contributes to a better understanding of the influences of natural stressors like temperature on biomarkers commonly used in

  2. The biology of perch and related fish

    National Research Council Canada - National Science Library

    Craig, John F; Craig, John

    1987-01-01

    This book presents a definitive volume on perch and related fish. In the introduction an outline is given on the characteristics of the order Perciformes, the suborder Percoidea and the family Percidae...

  3. Marine spawning sites of perch Perca fluviatilis revealed by oviduct-inserted acoustic transmitters

    DEFF Research Database (Denmark)

    Skovrind, Mikkel; Christensen, Emil A.F.; Carl, Henrik

    2013-01-01

    In the 1970s, a flood-protection system dramatically changed a large part of the coastal environment of Køge Bugt, a bay in the western Baltic Sea, from open coast to a brackish lagoon habitat. An anadromous stock of European perch Perca fluviatilis seems to have benefitted from this change...... a strong proof of concept of oviduct-inserted acoustic transmitters in brackish and marine fish spawning studies. The transmitter expulsions were validated using an egg map, which was based on visual observations of perch egg-strands, and 11 of the 12 expulsed transmitters (92%) were located in areas...... with eggs. Many fish spawned in the brackish water with salinities up to 9.6 PSU. These salinities are higher than those previously observed for European perch spawning in the wild, and call for further investigations of salinity tolerance in perch eggs...

  4. Evidence for discrete subpopulations of sea perch (Helicolenus ercoides) across four fjords in Fiordland, New Zealand

    International Nuclear Information System (INIS)

    Lawton, R.J.; Wing, S.R.; Lewis, A.M.

    2010-01-01

    In coastal populations of invertebrates and fishes, the distribution of discrete subpopulations is influenced by adult and larval dispersal, as well as by the effects of habitat heterogeneity on site fidelity or connectivity. Here, we examine evidence for spatial structure of sea perch, Helicolenus percoides, populations among four fjords in the Fiordland region of southwestern New Zealand. We examine patterns in adult morphology, length-at-age, δ 13 C and δ 15 N of muscle tissue, and trace elemental composition of whole otoliths as proxies for population isolation among the four inner fjord regions. A multivariate analysis of morphometrics reveals significant differences among populations from each of the four sites, suggesting existence of four distinct subpopulations. These patterns are consistent with observed differences in δ 13 C and δ 15 N, and length-at-age estimates among the four subpopulations. Differences in whole otolith concentrations of Sr, Ba, Mg and Li, and high classification scores based on the whole otolith elemental fingerprint are also consistent with significant subdivision among areas. Patterns across all four markers are consistent with discrete subpopulation structure of adult sea perch among the four study sites. These data indicate that the newly implemented network of marine protected areas in Fiordland is likely to contain discrete populations of sea perch. (author).

  5. Interactions among zebra mussel shells, invertebrate prey, and Eurasian ruffe or yellow perch

    Science.gov (United States)

    Kolar, C.S.; Fullerton, A.H.; Martin, K.M.; Lamberti, G.A.

    2002-01-01

    The exotic zebra mussel, Dreissena polymorpha, is established in all of the Laurentian Great Lakes and may affect benthivorous fishes by increasing the complexity of benthic substrates and changing energy flow patterns within the food web. Native yellow perch, Perca flavescens, and the nonindigenous Eurasian ruffe, Gymnocephalus cernuus, are benthivores that may compete for limited food resources. As ruffe spread to areas with more dense zebra mussel populations, the zone of interaction among zebra mussels, yellow perch, and ruffe will increase and intensify. In the laboratory, the effect of zebra mussel shells on the ability of these fishes to forage on amphipods (Gammarus pseudolimnaeus) and chironomids (Chironomus plumosus) was examined in light and darkness. In 12 h, ruffe consumed more amphipods than did similar-sized yellow perch, particularly in darkness on bare cobble, and in light within zebra mussels. Amphipods decreased activity more in the presence of ruffe than yellow perch. More amphipods were found in zebra mussel shells than in bare cobble, whether or not fish were present. In darkness, when ruffe consumed more amphipods on bare cobble, amphipods became more associated with zebra mussel shells. Although ruffe consumed more amphipods than yellow perch, perch consumed more chironomids than ruffe on bare cobble. The presence of zebra mussel shells altered the relative consumption of invertebrates in some substrate-light combinations. Experiments such as these help to improve understanding of the direct and indirect effects of predation between and among native and nonindigenous species that may exert structuring forces on the nearshore communities of the Great Lakes currently or in the future.

  6. Behavioural strategy of large perch Perca fluviatilis varies between a mesotrophic and a hypereutrophic lake

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Berg, Søren; Baktoft, Henrik

    2015-01-01

    Behaviour of large perch Perca fluviatilis was studied in two lakes differing in environmental state i.e. mesotrophic v. hypereutrophic. A total of 20 adult perch P. fluviatilis (29–42 cm total length) in each lake were tagged with radio-transmitters, tracked and located eight times a day during...... six 24 h tracking periods over a year, enabling detection of differences in diel activity patterns and habitat use during summer and winter under two different environmental regimes. During summer, P. fluviatilis in the mesotrophic lake showed a distinct crepuscular activity pattern and a change from...... factor of large P. fluviatilis did not differ between the two lakes. Thus, it is suggested that P. fluviatilis in the hypereutrophic turbid lake adopted an alternative behaviour for successful foraging, being uniformly active throughout the diel cycle...

  7. Performance of free-range chickens reared in production modules enriched with shade net and perches

    Directory of Open Access Journals (Sweden)

    MJB Santos

    2014-03-01

    Full Text Available An experiment was carried out to evaluate the effect of environmental enrichment in a free-range chicken production system on live performance as a function of microclimate, physiological parameters, and performance parameters. Four production modules were divided into four pens with 10 birds each, totaling 60 birds. The following treatments were applied: access to a paddock (TEST, access to a paddock with perches (PER, access to a paddock with artificial shade (SHA, and access to the paddock with perches and artificial shade (PESH. The PESH production module presented the best globe temperature (Tbg,ºC and enthalpy (h, kJ/kg, and thereby, the best thermal environmental conditions, which ensured the longest permanence time of the birds in the paddock. The SHA and PESH modules promoted the lowest respiratory rate and shank and comb temperatures. Live performance was influenced by the presence of environmental enrichment (modules SHA and PESH, with the highest live weight (LW and weight gain (WG and the lowest feed conversion ratio (FCR and metabolizable energy intake (MEI. Parts yield, such as giblets, were not influenced by production modules, except for PESH, which promoted higher offal weight. In general, chickens reared in enriched production modules presented greatest performance and comfort results and were considered close to optimal rearing conditions.

  8. Use of perches and seed dispersal by birds in an abandoned pasture in the Porto Ferreira state park, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    S. Athiê

    Full Text Available Abstract We investigated the efficiency of different kinds of perches in attracting seed disperser-birds and increasing the seed rain in a degraded area located in the northeast region of São Paulo State. We installed seed traps under natural perches (NPs, living trees; simple artificial perches (SAPs of 3m tall and a crossbar; elaborate artificial perches (EAPs of 7m tall and three crossbars, and in a control area. Results showed the number of bird-dispersed seeds deposited was proportional to the number of structures for perching. The NPs also have provided other resources for birds such as food and shelter. Comparing visitation between artificial perches, there was greater use of EAPs also for having more perching structures and for being taller, providing better airspace visibility for predatory birds and tyrant-flycatchers, important seed dispersers. Thus, natural and artificial perches with similar characteristics to the EAPs are the most recommended as a base or complementary method for the restoration of degraded areas near to propagules source, also contributing to the maintenance of local fauna.

  9. A bacterial disease of yellow perch (Peres flavescens)

    Science.gov (United States)

    Ross, A.J.; Nordstrom, P.R.; Bailey, J.E.; Heaton, J.H.

    1960-01-01

    On May 26, 1959, two of the authors' investigated a fish kill at Dailey Lake, Park County, Montana. They observed about a half-dozen live, weakly swimming yellow perch (Perca flavescens), in addition to thousand of dead perch along the shoreline. It was learned from local residents that mortalities had begun to appear some 2 weeks earlier. At that time the time the authorities had diagnosed the condition as a winterkill, since ice had only recently disappeared from the lake. Although a number of other species inhabit Dailey Lake, including rainbow trout (Salmo gairdneri), brown trout (S. trutta), kokanee (Oncorhynchus nerka), black crappie (Pomoxis nigromaculatus), largemouth bass (Micropterus salmoides), longnose suckers (Catostomus catostomus), rainbow x cutthroat hybrids, only one other species was represented in the kill. This consisted of one black crappie.

  10. Challenge studies of European stocks of redfin perch, Perca fluviatilis L., and rainbow trout, Oncorhynchus mykiss (Walbaum), with epizootic haematopoietic necrosis virus

    DEFF Research Database (Denmark)

    Ariel, Ellen; Jensen, Ann Britt Bang

    2009-01-01

    indicate that EHNV does not pose a high risk for wild perch and trout populations in Europe by natural exposure. Mortality appears to be primarily a function of environmental factors, with temperature playing an important role, and not just the presence of the virus in the fish.......A challenge model for comparison of the virulence of epizootic haematopoietic necrosis virus (EHNV) to European stock of redfin perch, Perca fluviatilis L., and rainbow trout, Oncorhynchus mykiss (Walbaum), was tested. The model investigated intraperitoneal (IP), bath and cohabitation routes at 10...

  11. Fins coloration of perch in relation to external activity concentration of radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Yegoreichenkov, E.; Pryakhin, E. [Urals Research Center for Radiation Medicine (Russian Federation); Rudolfsen, G. [Norwegian Radiation Protection Authority and University of Tromsoe (Norway)

    2014-07-01

    The Techa River is significantly polluted by radionuclides. This time the content of {sup 90}Sr varies from 5 Bq/l in water of lower Techa to 40 Bq/l in higher Techa, and the concentration of {sup 137}Cs fluctuates from background content to 0,5 Bq/l, and tritium from 100 Bq/l to 450 Bq/l. Miass River are not polluted in the same extent. The perch in these rivers are suitable for examine the potential effect of environmental perturbation on carotenoid based coloration. As vertebrates could not produce carotenoids themselves, and would use more carotenoids due to oxidative stress when exposed radiation, we hypothesized that fish caught in upper part of Techa River will be more pale than fish from lower part and the control river Miass. We used a cost effective method to estimate coloration by photographing the fins in standardized setting. The measuring of fish fins as performed under standardized condition by Adobe Photoshop software in color spaces CIE 1976 L*a*b* and sRGB IEC61966-2.1 was used. In sRGB color space the values of Red, Green, Blue channels were measured and an average wave length was calculated as a function of three elementary light streams of different intensity, appeared as reflection from a fin. In L*a*b color space the values of *a and *b channels shows the position of a color in a color space. To evaluate the red color of a perch fin the most usable channel is the *a channel which shows the position of the color on the red-green axis. Due to low sample size we pooled males and females in our analysis. We used three different station in the Techa: RT-1 in the higher Techa, RT-2 in the middle Techa, and RT-3 in lower Techa. As a control group was taken the fish from Miass river (RM station). Our results shows that perch from RT-3 (570.7 nm) significantly differ in coloration from the perch from RT-2 and RT-1 (p=0.00001 and p=0.0014 respectively, hereinafter used Kruskal-Wallis rank sum test with Nemenyi-Damico-Wolfe-Dunn test as post

  12. Methods to assess impacts on Hudson River white perch: report for the period October 1, 1978 to September 30, 1979

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Kirk, B.L.; Kumar, K.D.; Van Winkle, W.; Vaughan, D.S.

    1980-06-01

    This report is a brief description of the work done on the NRC project entitled 'Methods to Assess Impacts on Hudson River White Perch' October 1, 1978 to September 30, 1979. Accounts of special studies of white perch entrainment at Hudson River power plants, of density-dependent growth in the Hudson River white perch population, and of data on the white perch populations of the Delaware and Chesapeake systems were performed. Complete accounts of these special studies are included in this report. During this period, a final draft topical report entitled 'Evaluation of Impingement Losses of White Perch at the Indian Point Nuclear Station and Other Hudson River Power Plants' (NUREG/CR-1100) was completed

  13. Bone-remodeling transcript levels are independent of perching in end-of-lay white leghorn chickens.

    Science.gov (United States)

    Dale, Maurice D; Mortimer, Erin M; Kolli, Santharam; Achramowicz, Erik; Borchert, Glenn; Juliano, Steven A; Halkyard, Scott; Sietz, Nick; Gatto, Craig; Hester, Patricia Y; Rubin, David A

    2015-01-23

    Osteoporosis is a bone disease that commonly results in a 30% incidence of fracture in hens used to produce eggs for human consumption. One of the causes of osteoporosis is the lack of mechanical strain placed on weight-bearing bones. In conventionally-caged hens, there is inadequate space for chickens to exercise and induce mechanical strain on their bones. One approach is to encourage mechanical stress on bones by the addition of perches to conventional cages. Our study focuses on the molecular mechanism of bone remodeling in end-of-lay hens (71 weeks) with access to perches. We examined bone-specific transcripts that are actively involved during development and remodeling. Using real-time quantitative PCR, we examined seven transcripts (COL2A1 (collagen, type II, alpha 1), RANKL (receptor activator of nuclear factor kappa-B ligand), OPG (osteoprotegerin), PTHLH (PTH-like hormone), PTH1R (PTH/PTHLH type-1 receptor), PTH3R (PTH/PTHLH type-3 receptor), and SOX9 (Sry-related high mobility group box)) in phalange, tibia and femur. Our results indicate that the only significant effect was a difference among bones for COL2A1 (femur > phalange). Therefore, we conclude that access to a perch did not alter transcript expression. Furthermore, because hens have been used as a model for human bone metabolism and osteoporosis, the results indicate that bone remodeling due to mechanical loading in chickens may be a product of different pathways than those involved in the mammalian model.

  14. Effects of fasting, temperature, and photoperiod on preproghrelin mRNA expression in Chinese perch.

    Science.gov (United States)

    Song, Yi; Zhao, Cheng; Liang, Xu-Fang; He, Shan; Tian, Changxu; Cheng, Xiaoyan; Yuan, Xiaochen; Lv, Liyuan; Guo, Wenjie; Xue, Min; Tao, Ya-Xiong

    2017-06-01

    Preproghrelin, a gut/brain peptide, plays an important role in the regulation of food intake and energy homeostasis in teleost and mammals. In the present study, we obtained the full-length preproghrelin cDNA in Chinese perch. The preproghrelin messenger RNA (mRNA) tissue expression showed that level was much higher in stomach and pituitary than in other tissues. The fasting study showed, after gastric emptying (3-6 h), short-term fasting (6-12 h) increased preproghrelin expression in the stomach. While in the pituitary, fasting reduced preproghrelin expression at 1, 3, 12, and 48 h, presenting state fluctuation of self-adjustment. The temperature study showed that the mRNA expression of preproghrelin was the highest in the brain at 26 °C and highest in the stomach at 32 °C, respectively, with different optimum temperature in these two tissues, reflecting spatiotemporal differences of regulation by central nervous system and peripheral organs. The photoperiod study showed that normal light (11 h of lightness and 13 h of darkness) led to highest preproghrelin expression, both in the brain and in the stomach, than continuous light or continuous dark, proving food intake is adapted to natural photoperiod or normal light in this study. These results all indicated that tissue-specific preproghrelin expression of Chinese perch could be significantly affected by environmental factors. Short-term fasting of 6 h after gastric emptying, 26 °C, and normal light led to higher preproghrelin expression, which indicated potential appetite increase in Chinese perch.

  15. Ecological carryover effects associated with partial migration in white perch (Morone americana) within the Hudson River Estuary

    Science.gov (United States)

    Gallagher, Brian K.; Piccoli, Philip M.; Secor, David H.

    2018-01-01

    Partial migration in complex life cycles allows environmental conditions experienced during one life-stage to interact with genetic thresholds and produce divergent spatial behaviors in the next stage. We evaluated partial migration over the entire life cycle of white perch, (Morone americana) within the Hudson River Estuary, combining otolith microchemistry, population demographics and environmental data analysis. Ecological carryover effects were used as a framework to test how environmental variation during the larval period influenced migration behaviors and growth characteristics in subsequent life-stages. Two annual cohorts of juveniles were classified based on whether they persisted in natal habitats (freshwater resident contingent) or dispersed into non-natal habitats (brackish water migratory contingent) as juveniles. The migratory contingent tended to hatch earlier and experience cooler temperatures as larvae, while the availability of zooplankton prey during the larval period appeared to influence growth dynamics before and after metamorphosis. Juvenile migration behaviors were reversible but usually persisted into adulthood. As juveniles, the consequences of partial migration on growth appeared to be modified by river flow, as demonstrated by the influence of a large storm event on feeding conditions in one of the study years. Migratory adults grew faster and attained larger maximum sizes, but may also experience higher rates of mortality. The interplay uncovered between life-stage transitions, conditional migration behaviors and habitat productivity throughout the life cycle shapes white perch population dynamics and will likely play an important role in responses to long-term environmental change.

  16. Perch Selection by Three Cooccurring Species of Celithemis (Odonata: Libellulidae: Testing for a Competitive Hierarchy among Similar Species

    Directory of Open Access Journals (Sweden)

    Wade B. Worthen

    2016-01-01

    Full Text Available In many communities of perching dragonflies (Odonata: Libellulidae, a size-dependent competitive hierarchy creates a positive relationship between male body size and perch height. We tested for this pattern among three similar-sized species: Celithemis elisa, C. fasciata, and C. ornata. Males were caught and photographed from May to July 2015 at Ashmore Heritage Preserve, Greenville County, SC, USA, and perch heights and perch distance to open water were measured. Five indices of body size were measured with ImageJ software: abdomen length, forewing length, hindwing length, area of forewing, and area of hindwing. Celithemis fasciata was significantly larger than the other two species for all five anatomical characters and used perches that were significantly taller and closer to open water than the other species, though these differences changed over the summer. Aggressive interactions between and within species were tallied and compared to expected distributions based on mean relative abundances derived from hourly abundance counts. Patterns of interspecific aggression were also consistent with a size-dependent hierarchy: the large C. fasciata was attacked less frequently, and the small C. ornata more frequently, than predicted by their relative abundances. We conclude that even small differences in body size may contribute to niche partitioning in perch selection.

  17. Nourishment of perched sand dunes and the issue of erosion control in the Great Lakes

    Science.gov (United States)

    Marsh, William M.

    1990-09-01

    Although limited in coverage, perched sand dunes situated on high coastal bluffs are considered the most prized of Great Lakes dunes. Grand Sable Dunes on Lake Superior and Sleeping Bear Dunes on Lake Michigan are featured attractions of national lakeshores under National Park Service management. The source of sand for perched dunes is the high bluff along their lakeward edge. As onshore wind crosses the bluff, flow is accelerated upslope, resulting in greatly elevated levels of wind stress over the slope brow. On barren, sandy bluffs, wind erosion is concentrated in the brow zone, and for the Grand Sable Bluff, it averaged 1 m3/yr per linear meter along the highest sections for the period 1973 1983. This mechanism accounts for about 6,500 m3 of sand nourishment to the dunefield annually and clearly has been the predominant mechanism for the long-term development of the dunefield. However, wind erosion and dune nourishment are possible only where the bluff is denuded of plant cover by mass movements and related processes induced by wave erosion. In the Great Lakes, wave erosion and bluff retreat vary with lake levels; the nourishment of perched dunes is favored by high levels. Lake levels have been relatively high for the past 50 years, and shore erosion has become a major environmental issue leading property owners and politicians to support lake-level regulation. Trimming high water levels could reduce geomorphic activity on high bluffs and affect dune nourishment rates. Locally, nourishment also may be influenced by sediment accumulation associated with harbor protection facilities and by planting programs aimed at stabilizing dunes.

  18. Rapid area change in pitch-up manoeuvres of small perching birds.

    Science.gov (United States)

    Polet, D T; Rival, D E

    2015-10-26

    Rapid pitch-up has been highlighted as a mechanism to generate large lift and drag during landing manoeuvres. However, pitching rates had not been measured previously in perching birds, and so the direct applicability of computations and experiments to observed behaviour was not known. We measure pitch rates in a small, wild bird (the black-capped chickadee; Poecile atricapillus), and show that these rates are within the parameter range used in experiments. Pitching rates were characterized by the shape change number, a metric comparing the rate of frontal area increase to acceleration. Black-capped chickadees increase the shape change number during perching in direct proportion to their total kinetic and potential energy at the start of the manoeuvre. The linear relationship between dissipated energy and shape change number is in accordance with a simple analytical model developed for two-dimensional pitching and decelerating airfoils. Black-capped chickadees use a wing pitch-up manoeuvre during perching to dissipate energy quickly while maintaining lift and drag through rapid area change. It is suggested that similar pitch-and-decelerate manoeuvres could be used to aid in the controlled, precise landings of small manoeuvrable air vehicles.

  19. Robust post-stall perching with a simple fixed-wing glider using LQR-Trees

    International Nuclear Information System (INIS)

    Moore, Joseph; Cory, Rick; Tedrake, Russ

    2014-01-01

    Birds routinely execute post-stall maneuvers with a speed and precision far beyond the capabilities of our best aircraft control systems. One remarkable example is a bird exploiting post-stall pressure drag in order to rapidly decelerate to land on a perch. Stall is typically associated with a loss of control authority, and it is tempting to attribute this agility of birds to the intricate morphology of the wings and tail, to their precision sensing apparatus, or their ability to perform thrust vectoring. Here we ask whether an extremely simple fixed-wing glider (no propeller) with only a single actuator in the tail is capable of landing precisely on a perch from a large range of initial conditions. To answer this question, we focus on the design of the flight control system; building upon previous work which used linear feedback control design based on quadratic regulators (LQR), we develop nonlinear feedback control based on nonlinear model-predictive control and ‘LQR-Trees’. Through simulation using a flat-plate model of the glider, we find that both nonlinear methods are capable of achieving an accurate bird-like perching maneuver from a large range of initial conditions; the ‘LQR-Trees’ algorithm is particularly useful due to its low computational burden at runtime and its inherent performance guarantees. With this in mind, we then implement the ‘LQR-Trees’ algorithm on real hardware and demonstrate a 95 percent perching success rate over 147 flights for a wide range of initial speeds. These results suggest that, at least in the absence of significant disturbances like wind gusts, complex wing morphology and sensing are not strictly required to achieve accurate and robust perching even in the post-stall flow regime. (papers)

  20. Who is who: An anomalous predator-prey role exchange between cyprinids and perch.

    Czech Academy of Sciences Publication Activity Database

    Vejřík, Lukáš; Matějíčková, Ivana; Seďa, Jaromír; Blabolil, Petr; Jůza, Tomáš; Vašek, Mojmír; Ricard, Daniel; Matěna, Josef; Frouzová, Jaroslava; Kubečka, Jan; Říha, Milan; Čech, Martin

    2016-01-01

    Roč. 11, č. 6 (2016), č. článku e0156430. E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) EE2.3.20.0204; GA MŠk(CZ) 7F14316; GA ČR GP206/09/P266; GA ČR GA15-24309S; GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Abramis brama * Cyprinus carpio * piscivory * YOY perch * zooplankton Subject RIV: DA - Hydrology ; Limnology Impact factor: 2.806, year: 2016

  1. Are high perches in the blackcap Sylvia atricapilla song or listening posts? A sound transmission study

    DEFF Research Database (Denmark)

    Mathevon, Nicolas; Dabelsteen, Torben; Blumenrath, Sandra Helene

    2005-01-01

    Birds often sing from high perches referred to as song posts. However, birds also listen and keep a lookout from these perches. We used a sound transmission experiment to investigate the changes for receiving and sending conditions that a territorial songbird may experience by moving upwards...

  2. The effect of turbidity and prey fish density on consumption rates of piscivorous Eurasian perch Perca fluviatilis

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Berg, Søren; Baktoft, Henrik

    2014-01-01

    piscivorous Eurasian perch Perca fluviatilis L. This was done in outdoor mesocosm (16 m2) experiments with clear water and two levels of turbidity (25 and 105 NTU) and two prey fish densities [3.1 and 12.5 roach Rutilus rutilus (L.) individuals m–2]. Perch consumption rates were affected by visibility less...... than expected, while they were highly affected by increased prey fish density. Perch responded to high prey density in all visibility conditions, indicating that prey density is more crucial for consumption than visibility in turbid lakes...

  3. Branchial cadmium and copper binding and intestinal cadmium uptake in wild yellow perch (Perca flavescens) from clean and metal-contaminated lakes

    International Nuclear Information System (INIS)

    Klinck, J.S.; Green, W.W.; Mirza, R.S.; Nadella, S.R.; Chowdhury, M.J.; Wood, C.M.; Pyle, G.G.

    2007-01-01

    Branchial binding kinetics and gastro-intestinal uptake of copper and cadmium where examined in yellow perch (Perca flavescens) from a metal-contaminated lake (Hannah Lake, Sudbury, Ontario, Canada) and an uncontaminated lake (James Lake, North Bay, Ontario, Canada). An in vivo approach was taken for gill binding comparisons while an in vitro gut binding assay was employed for gastro-intestinal tract (GIT) uptake analysis. By investigating metal uptake at the gill and the gut we cover the two main routes of metal entry into fish. Comparisons of water and sediment chemistries, metal burdens in benthic invertebrate, and metal burdens in the livers of perch from the two study lakes clearly show that yellow perch from Hannah L. are chronically exposed to a highly metal-contaminated environment compared to a reference lake. We found that metal-contaminated yellow perch showed no significant difference in gill Cd binding compared to reference fish, but they did show significant decreases in new Cd binding and absorption in their GITs. The results show that gill Cd binding may involve low-capacity, high-affinity binding sites, while gastro-intestinal Cd uptake involves binding sites that are high-capacity, low-affinity. From this we infer that Cd may be more critically controlled at the gut rather than gills. Significant differences in branchial Cu binding (increased binding) were observed in metal-contaminated yellow perch. We suggest that chronic waterborne exposure to Cu (and/or other metals) may be the dominant influence in gill Cu binding rather than chronic exposure to high Cu diets. We give supporting evidence that Cd is taken up in the GIT, at least in part, by a similar pathway as Ca 2+ , principally that elevated dietary Ca 2+ reduces Cd binding and uptake. Overall our study reveals that metal pre-exposure via water and diet can alter uptake kinetics of Cu and Cd at the gill and/or the gut

  4. Branchial cadmium and copper binding and intestinal cadmium uptake in wild yellow perch (Perca flavescens) from clean and metal-contaminated lakes

    Energy Technology Data Exchange (ETDEWEB)

    Klinck, J.S. [Department of Biology, McMaster University, Hamilton, Ont. L8S 4K1 (Canada)], E-mail: klinckjs@mcmaster.ca; Green, W.W.; Mirza, R.S. [Department of Biology, McMaster University, Hamilton, Ont. L8S 4K1 (Canada); Department of Biology, Nipissing University, North Bay, Ont. P1B 8L7 (Canada); Nadella, S.R.; Chowdhury, M.J.; Wood, C.M. [Department of Biology, McMaster University, Hamilton, Ont. L8S 4K1 (Canada); Pyle, G.G. [Department of Biology, Nipissing University, North Bay, Ont. P1B 8L7 (Canada)

    2007-08-30

    Branchial binding kinetics and gastro-intestinal uptake of copper and cadmium where examined in yellow perch (Perca flavescens) from a metal-contaminated lake (Hannah Lake, Sudbury, Ontario, Canada) and an uncontaminated lake (James Lake, North Bay, Ontario, Canada). An in vivo approach was taken for gill binding comparisons while an in vitro gut binding assay was employed for gastro-intestinal tract (GIT) uptake analysis. By investigating metal uptake at the gill and the gut we cover the two main routes of metal entry into fish. Comparisons of water and sediment chemistries, metal burdens in benthic invertebrate, and metal burdens in the livers of perch from the two study lakes clearly show that yellow perch from Hannah L. are chronically exposed to a highly metal-contaminated environment compared to a reference lake. We found that metal-contaminated yellow perch showed no significant difference in gill Cd binding compared to reference fish, but they did show significant decreases in new Cd binding and absorption in their GITs. The results show that gill Cd binding may involve low-capacity, high-affinity binding sites, while gastro-intestinal Cd uptake involves binding sites that are high-capacity, low-affinity. From this we infer that Cd may be more critically controlled at the gut rather than gills. Significant differences in branchial Cu binding (increased binding) were observed in metal-contaminated yellow perch. We suggest that chronic waterborne exposure to Cu (and/or other metals) may be the dominant influence in gill Cu binding rather than chronic exposure to high Cu diets. We give supporting evidence that Cd is taken up in the GIT, at least in part, by a similar pathway as Ca{sup 2+}, principally that elevated dietary Ca{sup 2+} reduces Cd binding and uptake. Overall our study reveals that metal pre-exposure via water and diet can alter uptake kinetics of Cu and Cd at the gill and/or the gut.

  5. Bone-Remodeling Transcript Levels Are Independent of Perching in End-of-Lay White Leghorn Chickens

    Directory of Open Access Journals (Sweden)

    Maurice D. Dale

    2015-01-01

    Full Text Available Osteoporosis is a bone disease that commonly results in a 30% incidence of fracture in hens used to produce eggs for human consumption. One of the causes of osteoporosis is the lack of mechanical strain placed on weight-bearing bones. In conventionally-caged hens, there is inadequate space for chickens to exercise and induce mechanical strain on their bones. One approach is to encourage mechanical stress on bones by the addition of perches to conventional cages. Our study focuses on the molecular mechanism of bone remodeling in end-of-lay hens (71 weeks with access to perches. We examined bone-specific transcripts that are actively involved during development and remodeling. Using real-time quantitative PCR, we examined seven transcripts (COL2A1 (collagen, type II, alpha 1, RANKL (receptor activator of nuclear factor kappa-B ligand, OPG (osteoprotegerin, PTHLH (PTH-like hormone, PTH1R (PTH/PTHLH type-1 receptor, PTH3R (PTH/PTHLH type-3 receptor, and SOX9 (Sry-related high mobility group box in phalange, tibia and femur. Our results indicate that the only significant effect was a difference among bones for COL2A1 (femur > phalange. Therefore, we conclude that access to a perch did not alter transcript expression. Furthermore, because hens have been used as a model for human bone metabolism and osteoporosis, the results indicate that bone remodeling due to mechanical loading in chickens may be a product of different pathways than those involved in the mammalian model.

  6. The diet of reservoir perch before, during and after establishment of non-native tubenose goby

    Directory of Open Access Journals (Sweden)

    Všetičková Lucie

    2018-01-01

    Full Text Available In recent decades, gobiid species have increased their distribution throughout Europe and now often represent the dominant genus along many rivers and canals. In this study, we assessed the role of tubenose goby (Proterorhinus semilunaris as a prey species of native perch (Perca fluviatilis in a lowland reservoir soon after their initial introduction in 1994 (sampling started 1998 and 17 years after establishment (2011–2012. We compare these data with perch diet composition from before introduction (1981–1982. Our data indicate that tubenose gobies quickly became the dominant species along the reservoir bankside, making them an attractive prey for ≥1 + perch. There was a clear increasing trend in the numbers of larger perch caught along the rip-rap, with the largest fish clearly specialising on gobies. As such, introduction of tubenose gobies has had a pronounced effect on food web and population dynamics along the littoral zone. While goby numbers appear to have dropped significantly in recent years, apparently due to predation pressure, further studies are needed to assess whether such changes have had any general impact on population and food web dynamics within the reservoir.

  7. The energy requirements of Eurasian perch (Perca fluviatilis L.) in intensive culture

    DEFF Research Database (Denmark)

    Strand, A.; Overton, Julia Lynne; Alanara, A.

    2011-01-01

    requirements of this species. The aim of this study was to develop an energy requirement model for intensive culture of Eurasian perch reared at rational temperatures. Data on growth (the thermal unit growth coefficient, TGC, 3√g ‧ (℃ ‧ days)-1) and digestible energy need (DEN, kJ DE ‧ g -1) of Eurasian perch...... at a size range of 20–180 g and at temperatures of 17–23 ℃ were used. Regression analysis revealed that both TGC and DEN were affected significantly by fish size (P 0.05). Two models including body size of the fish were developed: (i) an inverse TGC model for evaluation...

  8. Using consumption rate to assess potential predators for biological control of white perch

    Directory of Open Access Journals (Sweden)

    Gosch N.J.C.

    2011-08-01

    Full Text Available Control of undesirable fishes is important in aquatic systems, and using predation as a tool for biological control is an attractive option to fishery biologists. However, determining the appropriate predators for biological control is critical for success. The objective of this study was to evaluate the utility of consumption rate as an index to determine the most effective predators for biological control of an invasive fish. Consumption rate values were calculated for nine potential predators that prey on white perch Morone americana in Branched Oak and Pawnee reservoirs, Nebraska. The consumption rate index provided a unique and insightful means of determining the potential effectiveness of each predator species in controlling white perch. Cumulative frequency distributions facilitated interpretation by providing a graphical presentation of consumption rates by all individuals within each predator species. Largemouth bass Micropterus salmoides, walleye Sander vitreus and sauger S. canadensis were the most efficient white perch predators in both reservoirs; however, previous attempts to increase biomass of these predators have failed suggesting that successful biological control is unlikely using existing predator species in these Nebraska reservoirs.

  9. Study of pike-perch (Sander lucioperca fishery from Razim Lake, Danube delta Romania

    Directory of Open Access Journals (Sweden)

    CERNIȘENCU Irina

    2018-05-01

    Full Text Available The Razim Lake is a great part of the Danube Delta Biosphere Reserve (DDBR, with a surface of 54,000 ha. Fish fauna from Razim lake include pike-perch (Sander lucioperca as one of the main top predators of fish community, however ecological significance indicates accessory species, recedent as dominance, sometimes been subrecedent species like in 2011 and 2012 sampling, but constant species regarding frequency in sampling. Otherwise, pike-perch is an important value DDBR fishery species with an average of 5% in total catch, range 2-10%, from what Razim lake contributes with average 71%, range 41-95% in the 1960-2015 period. Razim Lake has been in average 13%, range 1-40% from total Razim lake catch, in the same period of time. Since in RBDD has been fishing up to 2000 fisherman, in Razim lake activated up to 500 fishermen, however nowadays number of fishermen was regulated at lower range. Catch data series shows a continuous stock decline trend, considered to be a consequences of habitat degradation and over-exploitation. Fish stock estimation in last 15 years (2001-2016 support the hypothesis of over-exploitation. Based on length frequency structure of landings, the growth and exploitation parameters have been estimated as well as the average biomass and the maximum sustainable yields for the Razim lake pike-perch stock. Recommendation concerning fisheries management towards sustainable fishing of pike-perch stock, as increasing of cod-end seine mesh size and decreasing of fishing effort regulation are outlined.

  10. Effects of perched water on thermally driven moisture flow at the proposed Yucca Mountain repository for high-level waste

    International Nuclear Information System (INIS)

    Ofoegbu, G.I.; Bagtzoglou, A.C.; Green, R.T.; Muller, M.A.

    1999-01-01

    Numerical modeling was conducted to identify potential perched-water sites and examine the effects of perched water on thermally driven moisture flow at the proposed Yucca Mountain repository for high-level nuclear waste. It is demonstrated that perched-water zones may occur at two horizons on the up-dip side of faults such as the Ghost Dance Fault (GDF): in nonwelded volcanic strata [such as the Paintbrush Tuff nonwelded (PTn) stratigraphic unit], where juxtaposition of welded strata against nonwelded may constitute a barrier to lateral flow within the nonwelded strata; and in fractured horizons of underlying welded units [such as the Topopah Spring welded (TSw) unit] because of focused infiltration fed by overlying perched zones. The potential perched zones (PPZs) may contain perched water (which would flow freely into a well or opening) if infiltration rates are high enough. At lower infiltration rates, the PPZs contain only capillary-held water at relatively high saturations. Areas of the proposed repository that lie below PPZs are likely to experience relatively high percolation flux even if the PPZ contains only capillary-held water at high saturation. As a result, PPZs that contain only capillary-held water may be as important to repository performance as those that contain perched water. Thermal loading from emplaced waste in the repository is not likely to have an effect on PPZs located on adequate distance above the repository (such as in the PTn). As a result, such PPZs may be considered as permanent features of the environment. On the other hand, PPZs close to the repository depth (such as those that may occur in the TSw rock unit) would experience an initial period of spatial growth and increased saturation following waste emplacement. Thereafter, drying would begin at the repository horizon with perched-zone growth simultaneously above and below the repository. As a result, after the initial period of expansion, PPZs close to the repository horizon

  11. Impact of impingement on the Hudson River white perch population

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Van Winkle, W.

    1980-01-01

    The impact of power plant impingement on the 1974 and 1975 year classes of the Hudson River white perch population is assessed using a simple model derived from Ricker's theory of fisheries dynamics. The impact of impingement is expressed in the model as the conditional mortality rate, rather than as the more commonly used exploitation rate. Since the calculated impact is sensitive to errors in the estimation of population size and total mortality, ranges of probable values of these quantities are used to compute upper and lower bounds on the fractional reduction in abundance of each year class. Best estimates of abundance and mortality are used to compute the conditional impingement mortality rate separately for each plant and month. The results are used to assess the relative impacts of white perch impingement at six Hudson River power plants and to identify the seasons during which the impact is highest

  12. Salmonella and Vibrio cholerae in Nile perch ( Lates niloticus ...

    African Journals Online (AJOL)

    The Nile perch (Lates niloticus) industry in East Africa has suffered severe economic losses in the last few years due to failure to comply with the microbiological standards of European Union (E.U). Fresh and frozen products have been suspected to be contaminated with Salmonella and Vibrio cholerae. This has led to a ...

  13. Whole body and egg amino acid composition of Nile perch, Lates ...

    African Journals Online (AJOL)

    Windows User

    Nile perch (Lates niloticus) is a freshwater carnivorous fish and a couple of authors have ... relationship to the amino acid (AA) profile in fish because ... American catfish Rhamdia quelen (Meyer and Fracalossi,. 2005). ...... North Beach Western.

  14. Bird Perches Increase Forest Seeds on Puerto Rican Landslides.

    Science.gov (United States)

    Aaron B. Shiels; Lawrence R. Walker

    2003-01-01

    Landslides result in the loss of vertical vegetative structure, soil nutrients, and the soil seed bank. These losses impede timely recovery of tropical forest communities. In this study we added bird perches to six Puerto Rican landslides with three types of surfaces (bare, climbing fern, grass) in an effort to facilitate inputs of forest seeds through bird dispersal...

  15. Influence of artificially induced light pollution on the hormone system of two common fish species, perch and roach, in a rural habitat.

    Science.gov (United States)

    Brüning, Anika; Kloas, Werner; Preuer, Torsten; Hölker, Franz

    2018-01-01

    Almost all life on earth has adapted to natural cycles of light and dark by evolving circadian and circannual rhythms to synchronize behavioural and physiological processes with the environment. Artificial light at night (ALAN) is suspected to interfere with these rhythms. In this study we examined the influence of ALAN on nocturnal melatonin and sex steroid blood concentrations and mRNA expression of gonadotropins in the pituitary of European perch ( Perca fluviatilis ) and roach ( Rutilus rutilus ). In a rural experimental setting, fish were held in net cages in drainage channels experiencing either additional ALAN of ~15 lx at the water surface or natural light conditions at half-moon. No differences in melatonin concentrations between ALAN and natural conditions were detected. However, blood concentration of sex steroids (17β-estradiol; 11-ketotestosterone) as well as mRNA expression of gonadotropins (luteinizing hormone, follicle stimulating hormone) was reduced in both fish species. We conclude that ALAN can disturb biological rhythms in fish in urban waters. However, impacts on melatonin rhythm might have been blurred by individual differences, sampling methods and moonlight. The effect of ALAN on biomarkers of reproduction suggests a photo-labile period around the onset of gonadogenesis, including the experimental period (August). Light pollution therefore has a great potential to influence crucial life history traits with unpredictable outcome for fish population dynamics.

  16. Genetic characterization and relatedness of wild and farmed Eurasian perch (Perca fluviatilis: Possible implications for aquaculture practices

    Directory of Open Access Journals (Sweden)

    Sana Ben Khadher

    2016-05-01

    Full Text Available Aquaculture of the Eurasian perch, Perca fluviatilis, in recirculating systems has emerged over the past decades to become a significant way of diversification for inland areas in Europe. The development of such a production relies partly on the improvement of growth performance (i.e., reducing production costs, which requires suitable genetic management of broodstocks and the development of selective breeding programs. In this context, the present study was undertaken assessing for the first time the genetic diversity of farmed stocks of perch. Twelve microsatellite loci were used to investigate the genetic diversity of nine farmed stocks (547 individuals from two perch farms located in France and their supposedly wild founder population from Lake Geneva (394 individuals. First, the wild population displayed the lowest genetic diversity and differed genetically from all farmed populations except one, XB2. Second, genetic diversity did not decrease between farmed breeders and their potential offspring. However, in the three groups of broodstock-offspring the number of alleles decreased by 10%, 21%, and 15%, respectively. In addition, effective population size decreased in all offspring groups. A family structuring was also observed among broodstocks and their offspring, with an unequal family contribution being suspected. In the absence of parental information, these results attest to the utility of genetic tools to evaluate genetic diversity and the necessity of a monitoring program to maintain genetic variability among farmed perch. Genetic variability among farmed stocks appears to be sufficient for perch production to be sustainable and selective breeding programs to be developed. Keywords: Perca fluviatilis, Genetic diversity, Domestication, Microsatellites

  17. Minimum size limits for yellow perch (Perca flavescens) in western Lake Erie

    Science.gov (United States)

    Hartman, Wilbur L.; Nepszy, Stephen J.; Scholl, Russell L.

    1980-01-01

    During the 1960's yellow perch (Perca flavescens) of Lake Erie supported a commercial fishery that produced an average annual catch of 23 million pounds, as well as a modest sport fishery. Since 1969, the resource has seriously deteriorated. Commercial landings amounted to only 6 million pounds in 1976, and included proportionally more immature perch than in the 1960's. Moreover, no strong year classes were produced between 1965 and 1975. An interagency technical committee was appointed in 1975 by the Lake Erie Committee of the Great Lakes Fishery Commission to develop an interim management strategy that would provide for greater protection of perch in western Lake Erie, where declines have been the most severe. The committee first determined the age structure, growth and mortality rates, maturation schedule, and length-fecundity relationship for the population, and then applied Ricker-type equilibrium yield models to determine the effects of various minimum length limits on yield, production, average stock weight, potential egg deposition, and the Abrosov spawning frequency indicator (average number of spawning opportunities per female). The committee recommended increasing the minimum length limit of 5.0 inches to at least 8.5 inches. Theoretically, this change would increase the average stock weight by 36% and potential egg deposition by 44%, without significantly decreasing yield. Abrosov's spawning frequency indicator would rise from the existing 0.6 to about 1.2.

  18. Effects of habitat type on short- and long-term growth parameters of the European perch (Perca fluviatilis L.)

    Czech Academy of Sciences Publication Activity Database

    Petrtýl, M.; Kalous, L.; Frouzová, Jaroslava; Čech, Martin

    2015-01-01

    Roč. 100, č. 1 (2015), s. 13-20 ISSN 1434-2944 R&D Projects: GA ČR(CZ) GA206/06/1371; GA ČR(CZ) GP206/09/P266; GA MŠk(CZ) EE2.3.20.0204 Institutional support: RVO:60077344 Keywords : diel vertical migrations * RNA/DNA ratio * bathypelagic perch fry * growth rate * fish larvae * Římov Reservoir Subject RIV: GL - Fishing Impact factor: 1.459, year: 2015

  19. 36Cl in shallow, perched aquifers from central Indiana

    Science.gov (United States)

    Vogt, S.; Elmore, D.; Fritz, S. J.

    1994-06-01

    36Cl/Cl ratios and chloride concentrations were measured in several shallow, perched aquifers situated within glacial till in west-central Indiana (USA). Most of these aquifers show 36Cl/Cl ratios which have to be attributed to admixed 36Cl from nuclear weapons tests in the 1950s and 1960s. Two wells from Purdue's Horticultural Farm tap perched aquifers uninfluenced by anthropogenic sources of chloride, and their 36Cl/Cl ratios are comparable with ratios measured in modern, local precipitation. As such, the chloride contents of these wells (1 to 3 ppm) reflect evaporative concentration of the precipitation's chloride contents (averaging 0.17 ppm) in the vadose zone. Since one of these two wells (HA-2a) does not contain any detectable tritium, we conclude that recent pre-bomb 36Cl/Cl ratios and 36Cl deposition in precipitation are quite similar to those in modern precipitation. We attribute the slight 36Cl excess of about 20% in both of these wells largely to 36Cl deposition associated with dry fall-out. As much as 2 × 10 4 at. 36Cl/cm 2 might reach the surface via dry fall-out annually.

  20. Hydrological connectivity of perched aquifers and regional aquifers in semi-arid environments: a case study from Namibia

    Science.gov (United States)

    Hamutoko, J. T.; Wanke, H.

    2017-12-01

    Integrated isotopic and hydrological tracers along with standard hydrological data are used to understand complex dry land hydrological processes on different spatial and temporal scales. The objective of this study is to analyse the relationship between the perched aquifers and the regional aquifer using hydrochemical data and isotopic composition in the Cuvelai-Etosha Basin in Namibia. This relation between the aquifers will aid in understanding groundwater recharge processes and flow dynamics. Perched aquifers are discontinuous shallow aquifers with water level ranging from 0 to 30 meters below ground level. The regional aquifer occurs in semi-consolidated sandstone at depths between about 60 and 160 meters below ground level. Water samples were collected from both aquifers in 10 villages and were analysed for major ions and stable isotopes. The results show overlapping hydrochemistry and isotopic compositions of both aquifers in 8 villages which suggest the possibility of perched aquifer water infiltrating into the regional aquifer. In two villages the hydrochemistry and isotopic composition of the aquifers are totally different and this suggests that there is no interaction between this aquifers. Areas where perched aquifers are connected to regional aquifers maybe recharge zones. These finding have important implications for groundwater resource management.

  1. COMPARISON OF AGE ESTIMATES FROM VARIOUS HARD PARTS FOR REDFIN PERCH, Percafluviatilis, IN TASMANIA

    Directory of Open Access Journals (Sweden)

    Irwan Jatmiko

    2013-06-01

    Full Text Available Whole otoliths, sectioned otoliths, scales and vertebrae were used to select the most suitable for age determination of redfin perch, Percafluviatilis. Redfin perch were sampled from Trevallyn Lake and Brushy Lagoon using fyke nets, gillnets, electrofishing and rod and line angling. Age estimates were assessed for comparison between readings and among structures. One-wayANOVA of readability scores highlighted that sectioned otolith was the most obvious compare to other hard parts. Sectioned otoliths also showed the highest (93.9% agreement between readings, followed by vertebrae (68.7, scales (38.8 and whole otoliths (29.9. Furthermore, there were no significantly different (p>0.05 between first and second readings from sectioned otolith and vertebrae but significantly different (p <0.05 to those from scales and whole otoliths. When sectioned otoliths’ ages were compared with other structures, vertebrae showed the highest (47.6% agreement to those followed by scales (25.2% and whole otoliths (20.4%. Age estimates from sectioned otoliths were significantly different (p<0.05 to the values obtained from vertebrae, scales and whole otoliths.This finding demonstrated that sectioned otoliths are the best hard part for age determination for redfin perch in Tasmania.

  2. Intestinal parasite Acanthocephalus lucii (Acanthocephala) from European perch (Perca fluviatilis) as a bioindicator for lead pollution in the stream "Jevanský potok" near Prague, Czech Republic.

    Science.gov (United States)

    Jankovská, Ivana; Miholová, Daniela; Petrtýl, Miloslav; Romočuský, Stěpán; Kalous, Lukáš; Vadlejch, Jaroslav; Cadková, Zuzana; Langrová, Iva

    2011-03-01

    Lead concentrations in the tissues of perch and its parasites were determined as mg/kg dw. Lead was found at higher concentrations in the acanthocephalans (11.56) than in different tissues (liver, gonads and muscle with skin and bone) of perch. With respect to fish tissues, the highest concentrations of lead were present in the liver (1.24), followed by the gonads (0.57) whereas the lowest concentrations were in the muscle with skin and bone (0.21). The bioconcentration factors for lead indicated that parasites accumulate metals to a higher degree than fish tissues--lead concentrations in acanthocephalans were 9.32, 19.27 and 55.05 higher than in liver, gonads and muscles of host, respectively.

  3. Radiographic evaluation of perching-joint angles in cockatiels (Nymphicus hollandicus), Hispaniolan Amazon parrots (Amazona ventralis), and barred owls (Strix varia).

    Science.gov (United States)

    Bonin, Glen; Lauer, Susanne K; Guzman, David Sanchez-Migallon; Nevarez, Javier; Tully, Thomas N; Hosgood, Giselle; Gaschen, Lorrie

    2009-06-01

    Information on perching-joint angles in birds is limited. Joint immobilization in a physiologic perching angle has the potential to result more often in complete restoration of limb function. We evaluated perching-joint angles in 10 healthy cockatiels (Nymphicus hollandicus), 10 Hispaniolan Amazons (Amazona ventralis), and 9 barred owls (Strix varia) and determined intra- and interobserver variability for goniometric measurements in 2 different radiographic projections. Intra- and interobserver variation was less than 7% for all stifle and intertarsal joint measurements but frequently exceeded 10% for the hip-joint measurements. Hip, stifle, and intertarsal perching angles differed significantly among cockatiels, Hispaniolan Amazon parrots, and barred owls. The accuracy of measurements performed on straight lateral radiographic projections with superimposed limbs was not consistently superior to measurements on oblique projections with a slightly rotated pelvis. Stifle and intertarsal joint angles can be measured on radiographs by different observers with acceptable variability, but intra- and interobserver variability for hip-joint-angle measurements is higher.

  4. A comparative assessment of the adrenotoxic effects of cadmium in two teleost species, rainbow trout, Oncorhynchus mykiss, and yellow perch, Perca flavescens

    International Nuclear Information System (INIS)

    Lacroix, Alexandra; Hontela, Alice

    2004-01-01

    Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (trout O.mykiss =175.6>LC50/EC50 P.flavescens =37.7). Adrenocortical cells of trout were more sensitive than those of perch and Cd had a higher endocrine-disrupting potential and specificity in trout than in perch. However, in both species, Cd had the same effect on ACTH, dbcAMP and pregnenolone-stimulated cortisol secretion, with pregnenolone maintaining cortisol secretion until cell viability was impaired. These results confirm that for both species, Cd interferes in the signalling pathway of cortisol synthesis in a step prior to the pregnenolone formation. Data provided by the present study revealed important differences in vulnerability of adrenal steroidogenesis between rainbow trout and yellow perch

  5. Salinity tolerance of cultured Eurasian perch, Perca fluviatilis L.: Effects on growth and on survival as a function of temperature

    DEFF Research Database (Denmark)

    Overton, Julia Lynne; Bayley, M.; Paulsen, Helge

    2008-01-01

    Eurasian perch is generally only considered to be a candidate for freshwater aquaculture even though wild populations are found in estuarine and brackish water habitats. Little knowledge exists on two issues a) the effect of temperature on the salinity tolerance of perch and b) the long-term effe...

  6. An update of the distribution of selected radiochemical and chemical constituents in perched ground water, Idaho National Laboratory, Idaho, Emphasis 1999-2001

    Science.gov (United States)

    Davis, Linda C.

    2006-01-01

    Radiochemical and chemical wastes generated at facilities at the Idaho National Laboratory (INL) were discharged since 1952 to infiltration ponds at the Reactor Technology Complex (RTC) (known as the Test Reactor Area [TRA] until 2005), and the Idaho Nuclear Technology and Engineering Center (INTEC) and buried at the Radioactive Waste Management Complex (RWMC). Disposal of wastewater to infiltration ponds and infiltration of surface water at waste burial sites resulted in formation of perched ground water in basalts and in sedimentary interbeds above the Snake River Plain aquifer. Perched ground water is an integral part of the pathway for waste-constituent migration to the aquifer. The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, maintains ground-water monitoring networks at the INL to determine hydrologic trends, and to monitor the movement of radiochemical and chemical constituents in wastewater discharged from facilities to both perched ground water and the aquifer. This report presents an analysis of water-quality and water-level data collected from wells completed in perched ground water at the INL during 1999-2001, and summarizes historical disposal data and water-level-and water-quality trends. At the RTC, tritium, strontium-90, cesium-137, dissolved chromium, chloride, sodium, and sulfate were monitored in shallow and deep perched ground water. In shallow perched ground water, no tritium was detected above the reporting level. In deep perched ground water, tritium concentrations generally decreased or varied randomly during 1999-2001. During October 2001, tritium concentrations ranged from less than the reporting level to 39.4?1.4 picocuries per milliliter (pCi/mL). Reportable concentrations of tritium during July-October 2001 were smaller than the reported concentrations measured during July-December 1998. Tritium concentrations in water from wells at the RTC were likely affected by: well's distance from the

  7. Yellow perch embryo-larval survival and growth in surface waters associated with oil-sands mining

    International Nuclear Information System (INIS)

    Peters, L.E.; Heuvel, M.R. van den; Dixon, D.G.; Power, M.; Boerger, H.; MacKinnon, M.D.; Meer, T. Van

    1995-01-01

    As part of their land reclamation strategy, Syncrude Canada Ltd. is currently developing environmentally acceptable tailings disposal methods. Fine tailings, a suspension of clay and residual bitumen, is the waste product from oil sands extraction. Fine-tailings contain naphthenic acids, a group of saturated aliphatic and alicyclic carboxylic acids, which occur naturally in petroleum and are partly responsible for the toxicity of process water. The wet landscape method involves covering fine tails with a layer of water such that a self-sustaining ecosystem can be established. A 5 ha demonstration pond with a bottom of fine-tailings was constructed and stocked with yellow perch for experimental purposes. Two other reclaimed ponds formed with oil-sands overburden material were also stocked with perch. Adult perch sampled in the fall of 1995 from the experimental and reclaimed ponds exhibited a 2-fold induction of MFO activity compared to the source lake; indicating organic compound exposure. Perch from one of the reclaimed ponds showed significantly reduced circulating reproductive hormone levels, gonad size and smaller ovarian follicles. Reproductive parameters were not different between the source lake and the remaining ponds. Paired lab and field experiments were conducted to determine if contaminants present would be detrimental to egg viability and development of larvae either through direct exposure of spawned eggs or indirectly by effecting oogenesis. An early life stage toxicity test was also performed using commercially available naphthenic acid standard. Endpoints measured were percent fertilization, percent hatch, mortality, deformities, timing of developmental periods and larval growth

  8. Nile perch fish processing waste along Lake Victoria in East Africa ...

    African Journals Online (AJOL)

    Nile perch fish processing waste along Lake Victoria in East Africa: Auditing and characterization. ... African Journal of Environmental Science and Technology ... If you would like more information about how to print, save, and work with PDFs, Highwire Press provides a helpful Frequently Asked Questions about PDFs.

  9. A COMPARATIVE STUDY ON THE FEEDING COMPETITION OF THE EUROPEAN PERCH PERCA FLUVIATILIS L. AND THE RUFFE GYMNOCEPHALUS CERNUUS (L. IN LAKE PIEDILUCO (UMBRIA, ITALY.

    Directory of Open Access Journals (Sweden)

    LORENZONI M.

    2007-10-01

    Full Text Available The abundance of European perch in Lake Piediluco has significantly dwindled in the last few years. The present study on diet overlap between perch and ruffe was prompted by the rapid expansion of the ruffe stock in the lake. This species was first found in the lake in 1996 and has since become one of the most abundant. The degree of diet overlap between the two species was analyzed by using data on the stomach contents of 275 European perch and 328 ruffe. Results are expressed as abundance (%N, occurrence (%S, weight percentage (%W and index of predominance (Ip. The diet overlap index (α was calculated by means of Schoener’s formula using the %W of each food item. As an estimate of the diet width of both species, we used Levins’ indexes of niche breadth (B and standardized measurement of niche breadth (BA. Both species are strictly carnivorous, feeding mainly on invertebrates: the most important diet components were dipterans and crustaceans, but the European perch also feeds on fish. In the perch, the Levins index was greater (B=4.332 than that calculated for the ruffe (B=2.262. During the ontogenesis of the European perch, there is a rather pronounced diet shift: dipterans form the largest portion of the diet at all ages, though in older perch fish-eating becomes increasingly evident. Benthic crustaceans tend to be consumed in greater quantities by the 3+ age-class, though they are also found in the stomachs of specimens of all ages. Ruffe, by contrast, do not display a pronounced ontogenetic diet shift. The index of diet overlap between the two species was rather high, the maximum α value being 0.853; values indicate a high degree of diet overlap in the younger ageclasses (1+, 2+ and 3+, with a greater differentiation between the diets of the two species emerging as the age of the perch increased. Our research also clarified some of the biological characteristics of the European perch in Lake Piediluco, namely, theoretical growth in

  10. A comparative assessment of the adrenotoxic effects of cadmium in two teleost species, rainbow trout, Oncorhynchus mykiss, and yellow perch, Perca flavescens

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, Alexandra; Hontela, Alice

    2004-03-30

    Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (troutperch). Metals and particularly Cd impair cortisol secretion by adrenocortical cells in both species. The purpose of the present study was to assess in vitro the effect of Cd on cortisol secretion by adrenocortical cells of trout and perch, to compare the sensitivity of adrenal steroidogenesis in these two teleosts. Adrenocortical cells were exposed to Cd for 60 min, then stimulated with ACTH, dbcAMP or with pregnenolone, a cortisol precursor. Cd inhibited ACTH-stimulated cortisol secretion in a dose-dependent manner in both fish species, however, the EC50s (concentration resulting in 50% inhibition of cortisol secretion) was significantly lower in trout (EC50=0.09 mM) than perch (EC50=0.26 mM). To test the specificity of Cd to act as an endocrine disrupter, the LC50 (concentration that kills 50% of the cells) was also evaluated to determine the LC50/EC50 ratio (LC50/EC50{sub O.mykiss}=175.6>LC50/EC50{sub P.flavescens}=37.7). Adrenocortical cells of trout were more sensitive than those of perch and Cd had a higher endocrine-disrupting potential and specificity in trout than in perch. However, in both species, Cd had the same effect on ACTH, dbcAMP and pregnenolone-stimulated cortisol secretion, with pregnenolone maintaining cortisol secretion until cell viability was impaired. These results confirm that for both species, Cd interferes in the signalling pathway of cortisol synthesis in a step prior to the pregnenolone formation. Data provided by the present study revealed important differences in vulnerability of adrenal steroidogenesis between rainbow trout and yellow perch.

  11. Nile perch fish processing waste along Lake Victoria in East Africa ...

    African Journals Online (AJOL)

    In East Africa, Nile perch fish processing into chilled fish fillet for export along Lake Victoria generate large proportions of both solid and liquid wastes. However, no thorough auditing and characterization of the waste has been done that would guide potential value addition through bioconversions and waste management.

  12. Fatty acid composition of muscle and heart tissue of Nile perch ...

    African Journals Online (AJOL)

    The fatty acid composition in the heart tissue and muscle tissue of the Nile perch, Lates niloticus, and Nile tilapia, Oreochromis niloticus populations from Lakes Kioga and Victoria was determined by methanolysis and gas chromatography of the resulting fatty acid methyl esters. The analytical data were treated by ...

  13. Eutrophication, Nile perch and food-web interactions in south-east Lake Victoria

    NARCIS (Netherlands)

    Cornelissen, I.J.M.

    2015-01-01

    The increasing eutrophication, the introduction of Nile perch (Lates niloticus) and the increasing fishing pressure has changed Lake Victoria tremendously the last century. Since the 1960s, eutrophication increased primary production, enabling an increase in fish production. However,

  14. Interspecies differences in the accumulation of tributyltin and its metabolites under dietary exposure in sea perch, Lateolabrax japonicus, and red sea bream, Pagrus major.

    Science.gov (United States)

    Uno, Seiichi; Murakami, Masayo; Kokushi, Emiko; Koyama, Jiro

    2011-02-01

    Interspecies differences in the accumulation of dietary tributyltin (TBT) between sea perch, Lateolabrax japonicus, and red sea bream, Pagrus major, were studied. Although TBTs in both species reached steady-state condition in low-concentration group (L-group, 200 ng/g nominal concentration) by 1 week, it increased up to the end of exposure in high-concentration group (H-group, 3000 ng/g nominal concentration). In H-group, the accumulation rate of TBT in sea perch from 1 to 2 weeks was much higher than in red sea bream, which were 2.4-fold for sea perch and 1.7-fold for red sea bream, although TBT concentrations were similar between sea perch and red sea bream in L-group. Furthermore, in the H-group, the concentrations of TBT at 1 and 2 weeks were about 1.3- and 1.9-fold, respectively, higher in the sea perch than in the red sea bream. On the other hand, DBT residue in red sea bream was about 1.4-fold higher in sea perch for the L-group but concentrations were similar in both fishes for the H-group. These results suggest that red sea bream could metabolize faster the TBT to DBT than sea perch. This study also reveals that fish probably could absorb TBT through the food chain. The uptake of TBT by fish should be regarded in the real environment, because TBT concentration in seawater has been decreasing and now already at significantly low level. Copyright © 2009 Wiley Periodicals, Inc.

  15. Of paleo-genes and Perch: what if an "alien" is actually a native?

    Science.gov (United States)

    Stager, J Curt; Sporn, Lee Ann; Johnson, Melanie; Regalado, Sean

    2015-01-01

    Documenting whether a biotic taxon is native or alien to an ecosystem has theoretical value for ecological and evolutionary studies, and has practical value because it can potentially identify a taxon as a desirable component of an ecosystem or target it for removal. In some cases, however, such background information is inadequate or unavailable. Here we use paleo-DNA to re-evaluate the historical status of yellow perch in the 6 million acre Adirondack State Park of northern New York. Yellow perch DNA in a 2200-year sediment record reveals a long-term native status for these supposedly alien fish and challenges assumptions that they necessarily exclude native trout from upland lakes. Similar approaches could be applied to other species with uncertain historical distributions and could help to identify unrecognized pockets of biodiversity.

  16. Biology, History, Status and Conservation of Sacramento Perch, Archoplites interruptus

    Directory of Open Access Journals (Sweden)

    Patrick K Crain

    2011-04-01

    Full Text Available This paper is a review of the biology of Sacramento perch (Archoplites interruptus based mainly on recent studies of their distribution, ecology, physiology, and genetics. The Sacramento perch is the only member of the family Centrarchidae that is endemic to California. It is most closely related to the rock basses (Ambloplites spp. and is thought to have split from its eastern cousins during the Middle Miocene Period (15.5 to 5.2 million years ago, MYA. Their native range includes the Central Valley, Pajaro and Salinas rivers, tributaries to the San Francisco Estuary (e.g., Alameda Creek, and Clear Lake (Lake County. Today, they are most likely extirpated from all of their native range. They are known to persist in 28 waters outside their native range: 17 in California, nine in Nevada, and one each in Utah and Colorado. Disappearance from their native range coincided with massive changes to aquatic habitats in the Central Valley and with the introduction of alien species, including other centrarchids. Unfortunately, many populations established outside their native range have also disappeared and are continuing to do so.

  17. Of paleo-genes and Perch: what if an "alien" is actually a native?

    Directory of Open Access Journals (Sweden)

    J Curt Stager

    Full Text Available Documenting whether a biotic taxon is native or alien to an ecosystem has theoretical value for ecological and evolutionary studies, and has practical value because it can potentially identify a taxon as a desirable component of an ecosystem or target it for removal. In some cases, however, such background information is inadequate or unavailable. Here we use paleo-DNA to re-evaluate the historical status of yellow perch in the 6 million acre Adirondack State Park of northern New York. Yellow perch DNA in a 2200-year sediment record reveals a long-term native status for these supposedly alien fish and challenges assumptions that they necessarily exclude native trout from upland lakes. Similar approaches could be applied to other species with uncertain historical distributions and could help to identify unrecognized pockets of biodiversity.

  18. Diphyllobothrium latum in Italy: plerocercoids larvae distribution in perch (Perca fluviatilis fillets

    Directory of Open Access Journals (Sweden)

    MariaLetizia Fioravanti

    2013-04-01

    Full Text Available Following the diffusion of new eating habits (consumption of uncooked, undercooked, marinated or cold-smoked fish, some cases of parasitic zoonosis from freshwater fish are recently reappeared in Italy. One of these is tapeworm Diphyllobothrium latum, whose final host could be human. This study aimed to individuate the position of plerocercoid larvae inside perch fillets (Perca fluviatilis caught in 4 different sites on Como lake in 2011. The fish analyzed were 390. The larvae totally isolated from 112 positive fishes were 164: 85 found in the right fillets and 79 in left ones. According to dorso-ventral disposition in fish, 144 larvae were individuated in dorsal muscles and 20 in ventral ones. Data collected confirm that plerocercoid larvae prefer the upper mass of perch muscle. Dietary education and sanitary care on fish supply are necessary to prevent the diffusion of tapeworm zoonosis in high-risk zones. European legislation establishes freezing to sanitize fish to be eaten raw, marinated or cold-smoked.

  19. Live transport of Yellow Perch and Nile Tilapia in AQUI-S 20E (10% Eugenol) at high loading densities

    Science.gov (United States)

    Cupp, Aaron R.; Schreier, Theresa M.; Schleis, Sue M.

    2017-01-01

    Fish transport costs are a substantial portion of the operational expenses for aquaculture facilities in the USA. Safely transporting higher loading densities of fish would benefit haulers by increasing efficiency and reducing costs, but research evaluating transport for individual species is generally lacking. In this study, Yellow Perch Perca flavescens and Nile Tilapia Oreochromis niloticus were transported for 6 h immersed in water containing AQUI-S 20E (10% eugenol) at fish loading densities of 240 g/L (2 lb/gal) for perch and 480 g/L (4 lb/gal) for tilapia. Survival was quantified for fish transported in AQUI-S 20E concentrations of (1) control or 0 mg/L of water, (2) 100 mg/L, or (3) 200 mg/L. Yellow Perch had 98–100% survival, and Nile Tilapia had 100% survival up to through 14 d after transport across all AQUI-S 20E levels, including the control. Eugenol concentrations decreased rapidly in transport tank water, and fish showed no signs of sedation by the end of transport. We conclude that live transport of Yellow Perch and Nile Tilapia at higher loading densities resulted in high survival regardless of the AQUI-S 20E concentrations we tested.

  20. Perches and elevated platforms in commercial broiler farms: use and effect on walking ability, incidence of tibial dyschondroplasia and bone mineral content.

    Science.gov (United States)

    Kaukonen, E; Norring, M; Valros, A

    2017-05-01

    Modern fast-growing broilers spend excessive periods resting and their activity further decreases with age. Inactivity has been suggested to increase impaired gait and the incidence of leg disorders. Tibial dyschondroplasia (TD) is a common leg pathology in broilers. A more complex environment might facilitate more activity and improve leg health. Perches or elevated platforms bring variety to broilers' environment and could motivate more locomotion. This study examined the impact of perches and elevated platforms on walking ability, the occurrence of TD and level of bone ash and mineral contents. The investigation was performed on four commercial broiler farms throughout six consecutive batches with platforms and four to five with perches. On each farm at least two separate houses were included, enabling the comparison of furnished flocks to control flocks during each batch. Plastic slats with ramp access elevated by 30 cm or wooden perches of 10 and 30 cm height were offered in the furnished house. Farmers recorded the platform and perch usage twice a week with a five-point scale. Gait was scored before slaughter on a six-point scale according to the Welfare Quality® assessment protocol for poultry. The severity of TD was determined using a four-point scale on farm from all birds gait scored as 3 and at slaughter from 200 birds/flock. Farmers estimated 50% to 100% of the platforms to be occupied in all flocks throughout the entire growing period. Only single birds were perching, thus perch structures were constantly evaluated to be empty. Due to the low use, the perch-equipped houses were excluded when analysing bone content, walking ability and TD. On average, 30% of the tested birds exhibited gait score ⩾3. Younger scoring age resulted in a lower mean gait score and a lower percentage of scores 3 and 4 to 5. Overall, 2.3% of the birds examined at slaughter and 3.5% of the birds with gait score 3 were affected by TD. Leg health was better in birds with access

  1. Mechanisms of Egg Yolk Formation and Implications on Early Life History of White Perch (Morone americana.

    Directory of Open Access Journals (Sweden)

    Justin Schilling

    Full Text Available The three white perch (Morone americana vitellogenins (VtgAa, VtgAb, VtgC were quantified accurately and precisely in the liver, plasma, and ovary during pre-, early-, mid-, and post-vitellogenic oocyte growth using protein cleavage-isotope dilution mass spectrometry (PC-IDMS. Western blotting generally mirrored the PC-IDMS results. By PC-IDMS, VtgC was quantifiable in pre-vitellogenic ovary tissues and VtgAb was quantifiable in pre-vitellogenic liver tissues however, neither protein was detected by western blotting in these respective tissues at this time point. Immunohistochemistry indicated that VtgC was present within pre-vitellogenic oocytes and localized to lipid droplets within vitellogenic oocytes. Affinity purification coupled to tandem mass spectrometry using highly purified VtgC as a bait protein revealed a single specific interacting protein (Y-box binding protein 2a-like [Ybx2a-like] that eluted with suramin buffer and confirmed that VtgC does not bind the ovary vitellogenin receptors (LR8 and Lrp13. Western blotting for LR8 and Lrp13 showed that both receptors were expressed during vitellogenesis with LR8 and Lrp13 expression highest in early- and mid-vitellogenesis, respectively. The VtgAa within the ovary peaked during post-vitellogenesis, while VtgAb peaked during early-vitellogenesis in both white perch and the closely related striped bass (M. saxatilis. The VtgC was steadily accumulated by oocytes beginning during pre-vitellogenesis and continued until post-vitellogenesis and its composition varies widely between striped bass and white perch. In striped bass, the VtgC accounted for 26% of the vitellogenin-derived egg yolk, however in the white perch it comprised only 4%. Striped bass larvae have an extended developmental window and these larvae have yolk stores that may enable them to survive in the absence of food for twice as long as white perch after hatch. Thus, the VtgC may play an integral role in providing nutrients to

  2. Development of an enzyme-linked immunosorbent assay for detection of chicken osteocalcin and its use in evaluation of perch effects on bone remodeling in caged White Leghorns.

    Science.gov (United States)

    Jiang, S; Cheng, H W; Hester, P Y; Hou, J-F

    2013-08-01

    Osteocalcin (OC) is a sensitive biochemical marker for evaluating bone turnover in mammals. The role of avian OC is less clear because of the need for a chicken assay. Our objectives were to develop an assay using indirect competitive ELISA for detecting chicken serum OC and use the assay to examine the effects of perches on bone remodeling in caged hens. Anti-chicken OC polyclonal antibody was produced by immunization of rabbits with a recombinant OC from Escherichia coli. Chicken OC extracted from bone was used as a coated protein, and purified chicken OC was used for calibration. The limit of detection of the developed OC ELISA was 0.13 ng/mL. The intra- and interassay CV were housed in conventional cages with or without perches. Serum samples were collected from 71-wk-old White Leghorn hens subjected to 4 treatments. Treatment 1 was control chickens that never had access to perches during their life cycle. Treatment 2 chickens had perches during the pullet phase (0 to 16.9 wk of age), whereas treatment 3 chickens had perches only during the egg-laying phase of the life cycle (17 to 71 wk of age). Treatment 4 chickens always had access to perches (0 to 71 wk of age). Correlation between the 2 assays was 0.62 (P < 0.0001). Levels of serum OC using the developed chicken ELISA were higher than that detected using the Rat-Mid ELISA (P < 0.0001). Results from the chicken ELISA assay showed that hens with perch access had higher concentrations of serum OC than hens without perches during egg laying (P = 0.04). Pullet access to perches did not affect serum OC levels in 71-wk-old hens (P = 0.15). In conclusion, a chicken OC ELISA has been validated that is sensitive and accurate with adequate discriminatory power for measuring bone remodeling in chickens.

  3. A Transient Numerical Simulation of Perched Ground-Water Flow at the Test Reactor Area, Idaho National Engineering and Environmental Laboratory, Idaho, 1952-94

    International Nuclear Information System (INIS)

    Orr, B. R.

    1999-01-01

    Studies of flow through the unsaturated zone and perched ground-water zones above the Snake River Plain aquifer are part of the overall assessment of ground-water flow and determination of the fate and transport of contaminants in the subsurface at the Idaho National Engineering and Environmental Laboratory (INEEL). These studies include definition of the hydrologic controls on the formation of perched ground-water zones and description of the transport and fate of wastewater constituents as they moved through the unsaturated zone. The definition of hydrologic controls requires stratigraphic correlation of basalt flows and sedimentary interbeds within the saturated zone, analysis of hydraulic properties of unsaturated-zone rocks, numerical modeling of the formation of perched ground-water zones, and batch and column experiments to determine rock-water geochemical processes. This report describes the development of a transient numerical simulation that was used to evaluate a conceptual model of flow through perched ground-water zones beneath wastewater infiltration ponds at the Test Reactor Area (TRA)

  4. Observations of Eurasian perch (Perca fluviatilis L. post-larvae growth performances reared in an illuminated floating cage in Varese lake (N-W Italy over a two years period

    Directory of Open Access Journals (Sweden)

    Micaela Antonini

    2010-02-01

    Full Text Available Eurasian perch (P. fluviatilis is a very important fish species in Varese lake (N-W Italy. Since the second half of 20th century, perch catches in the lake have steadily decreased and by the end of the ‘80s the species resulted clearly endangered. The purpose of this study was to investigate growth, mortality and feeding conditions of perch postlarvae, reared in illuminated floating cage in Varese lake, to obtain fingerlings for a restocking program. In June 2006 and 2007, groups of 280 and 300 pre-weaned post-larvae (average body weight 0.64±0.09 g and 0.25±0.08 g respectively P<0.01 were held in an illuminated net cage for 90 days. The cage was illuminated inside from 20:30 p.m. to 6:30 a.m. During the trial, the nightly zooplankton accumulation inside the cage was assessed weekly. At night time the zooplankton biomass, which resulted dominated by Cladocera family, was higher inside the cage than in the lake. In 2006, 322±36 zooplankters L–1 were observed, compared to 945±600 observed in 2007 (P<0.05. In the lake, the number of zooplankters per litre was similar in both years, resulting in 63.3±50.30 and 61.10±45 zooplankters L–1, respectively on 2006 and 2007. In order to assess perch growth performances, 25 fishes were sampled from the cage every 15-20 days and length (cm and weight (g were assessed for each sample. At the end of September, specific growth rate (SGR and survival rate were assessed. In 2006 the final mean body weight of the perch fry was 4.65±1.47 g and that results significantly lower (P<0.05 than of 2007 (6.3±1.69 g. The SGR was 2.04% and 3.42%, respectively. The higher growth rate observed in 2007 was influenced by a higher zooplankton accumulation in the cage due to an improved cage management. In order to assess the cage efficiency, in September 2006 and 2007, the weight of young-of-year perch (n=50 captured in the lake were compared to those of reared fish. Wild fry showed a mean body weight significantly

  5. Biochemical and ultrastructural changes in the liver of European perch (Perca fluviatilis L. in response to cyanobacterial bloom in the Gruža reservoir

    Directory of Open Access Journals (Sweden)

    Perendija Branka R.

    2011-01-01

    Full Text Available We investigated the biochemical and ultrastructural changes in the liver of the freshwater fish, European perch (Perca fluviatilis, in response to Aphanizomenon flos-aquae bloom in the Gruža Reservoir, Serbia. The activities of total manganese- and copper zinc-containing superoxide dismutase (Tot SOD, Mn-SOD, Cu/Zn-SOD, catalase (CAT, glutathione peroxidase (GSH-Px, glutathione reductase (GR and biotransformation phase II enzyme glutathione-S-transferase (GST, as well as concentrations of total glutathione (GSH and sulfhydryl (-SH groups were examined before and during the bloom period. Mn-SOD activity was significantly higher, while the activities of Cu/Zn-SOD, CAT and GSH-Px and the concentration of the -SH groups were significantly lower during the bloom. The ultrastructure of the liver revealed necrotic and apoptotic damage to the hepatocytes during the bloom period. Our work represents the first study to report the influences of an Aphanizomenon flos-aquae bloom in the Gruža Reservoir on antioxidant biomarkers and on histopathological alterations in the liver of the freshwater fish European perch (Perca fluviatilis.

  6. Field-Derived Hydraulic Properties for Perched-Water Aquifer Wells 299-E33-350 and 299-E33-351, Hanford Site B-Complex Area

    Energy Technology Data Exchange (ETDEWEB)

    Newcomer, Darrell R.

    2014-07-01

    During February and March 2014, Pacific Northwest National Laboratory conducted hydraulic (slug) tests at 200-DV-1 Operable Unit wells 299-E33-350 (C8914) and 299-E33-351 (C8915) as part of B-Complex Area Perched-Water characterization activities at the Hanford Site 200-East Area. During the construction/completion phase of each well, two overlapping depth intervals were tested within the unconfined perched-water aquifer contained in the silty-sand subunit of the Cold Creek Unit. The purpose of the slug-test characterization was to provide estimates of transmissivity and hydraulic conductivity for the perched-water aquifer at these selected well locations.

  7. Geochemistry and hydrology of perched groundwater springs: assessing elevated uranium concentrations at Pigeon Spring relative to nearby Pigeon Mine, Arizona (USA)

    Science.gov (United States)

    Beisner, Kimberly R.; Paretti, Nicholas; Tillman, Fred; Naftz, David L.; Bills, Donald; Walton-Day, Katie; Gallegos, Tanya J.

    2017-01-01

    The processes that affect water chemistry as the water flows from recharge areas through breccia-pipe uranium deposits in the Grand Canyon region of the southwestern United States are not well understood. Pigeon Spring had elevated uranium in 1982 (44 μg/L), compared to other perched springs (2.7–18 μg/L), prior to mining operations at the nearby Pigeon Mine. Perched groundwater springs in an area around the Pigeon Mine were sampled between 2009 and 2015 and compared with material from the Pigeon Mine to better understand the geochemistry and hydrology of the area. Two general groups of perched groundwater springs were identified from this study; one group is characterized by calcium sulfate type water, low uranium activity ratio 234U/238U (UAR) values, and a mixture of water with some component of modern water, and the other group by calcium-magnesium sulfate type water, higher UAR values, and radiocarbon ages indicating recharge on the order of several thousand years ago. Multivariate statistical principal components analysis of Pigeon Mine and spring samples indicate Cu, Pb, As, Mn, and Cd concentrations distinguished mining-related leachates from perched groundwater springs. The groundwater potentiometric surface indicates that perched groundwater at Pigeon Mine would likely flow toward the northwest away from Pigeon Spring. The geochemical analysis of the water, sediment and rock samples collected from the Snake Gulch area indicate that the elevated uranium at Pigeon Spring is likely related to a natural source of uranium upgradient from the spring and not likely related to the Pigeon Mine.

  8. Enhancing effect of spawning on elimination of a persistent polychlorinated biphenyl from female yellow perch

    International Nuclear Information System (INIS)

    Vodicnik, M.J.; Peterson, R.E.

    1985-01-01

    Distribution and elimination of 2,5,2',5'-tetrachloro[14C]biphenyl (4-CB) were studied for 6 months after exposing sexually mature female yellow perch to the compound in water and transferring them to flowing 4-CB-free water. Perch that were exposed in January spawned in May, and the study was terminated in June. During the first 41/2 months after exposure, the t1/2 for whole-body elimination was 22 weeks, primarily by elimination of 4-CB from the viscera and carcass. During spawning, enhanced elimination (t1/2 less than 0.7 weeks) was due to the voiding of eggs containing 4-CB. After spawning, whole-body elimination returned to a slower rate (t1/2 = 16.3 weeks). Prior to the enhancement in 4-CB elimination rate during spawning, there was a redistribution of 4-CB residues within the body of the perch which was characterized by a transfer of 4-CB residues from primarily the carcass and viscera to eggs. Two weeks after exposure, 30% of the initial 4-CB body burden was distributed to the eggs, whereas just prior to spawning, about 50% was present in this tissue. These findings demonstrate that egg maturation and spawning result in a significant reduction in the body burden of a persistent polychlorinated biphenyl in a lean-fish species

  9. First evidence for postzygotic reproductive isolation between two populations of Eurasian perch (Perca fluviatilis L. within Lake Constance

    Directory of Open Access Journals (Sweden)

    Gerlach Gabriele

    2008-01-01

    Full Text Available Abstract Background The evolution of reproductive traits, such as hybrid incompatibility (postzygotic isolation and species recognition (prezygotic isolation, have shown their key role in speciation. Theoretical modeling has recently predicted that close linkage between genes controlling pre- and postzygotic reproductive isolation could accelerate the conditions for speciation. Postzygotic isolation could develop during the sympatric speciation process contributing to the divergence of populations. Using hybrid fitness as a measure of postzygotic reproductive isolation, we empirically studied population divergence in perch (Perca fluviatilis L. from two genetically divergent populations within a lake. Results During spawning time of perch we artificially created parental offspring and F1 hybrids of the two populations and studied fertilization rate and hatching success under laboratory conditions. The combined fitness measure (product of fertilization rate and hatching success of F1 hybrids was significantly reduced compared to offspring from within population crosses. Conclusion Our results suggest intrinsic genetic incompatibility between the two populations and indicate that population divergence between two populations of perch inhabiting the same lake may indeed be promoted by postzygotic isolation.

  10. Isolation of an iridovirus from pike-perch Stizostedion lucioperca

    DEFF Research Database (Denmark)

    Tapiovaara, H.; Olesen, Niels Jørgen; Linden, J.

    1998-01-01

    We have isolated a large virus from pike-perch Stizostedion lucioperca fingerlings with no signs of disease. The biochemical, structural, and serological properties of this newly isolated virus suggest that it belongs to the family Iridoviridae. The virus multiplied and was cytopathogenic...... fish iridoviruses. It is an enveloped icosahedral DNA virus. The diameter of the nucleocapsid in thin sections was 127 +/- 3 nm; in negatively stained preparates the size of the enveloped virus varied from 147 to 187 nm. In immunofluorescence the virus was stained by rabbit antisera against EHN...

  11. Experimental infection with epizootic haematopoietic necrosis virus (EHNV of rainbow trout (Oncorhynchus mykiss Walbaum and European perch (Perca fluviatilis L.

    Directory of Open Access Journals (Sweden)

    Borzym Ewa

    2015-12-01

    Full Text Available The aim of this study was the determination of the susceptibility of Polish farmed redfin perch (Perca fluviatilis L. and rainbow trout (Oncorhynchus mykiss Walbaum to experimental infection with haematopoietic necrosis virus (EHNV. A bath challenge model was tested at two temperature ranges: 13-15°C and 20-22°C. After 7 d, the first clinical signs and mortality were observed in fish kept at these temperatures. Significantly more mortality cases were reported in the redfin perch population, reaching a maximum of 24% compared with 12% in the rainbow trout group at 20-22°C. EHNV was reisolated from redfin perch and rainbow trout tissue in cell culture and the infection was confirmed by a molecular method and histopathology during the duration of the experiment. This study revealed that fish from Polish farms can be susceptible to EHNV even at lower temperatures.

  12. Yellow perch larval survival in the Zekiah Swamp watershed (Wicomico River, Maryland) relative to the potential effects of a coal ash storage facility

    International Nuclear Information System (INIS)

    Burton, W.H.; Pinkney, A.E.

    1994-01-01

    A coordinated program of in situ and laboratory bioassays supported by water quality analyses was used to evaluate the potential effect of a coal ash storage facility on a yellow perch (Perca flavescens) spawning area. The facility is located in the Zekiah Swamp watershed, a tributary of the Wicomico River, MD. In situ bioassays were conducted in Zekiah Swamp Run and reference locations in 1989 and 1990. Larval mortality was high in non-tidal areas of Zekiah Swamp Run, both at a site upstream and beyond the influence of the facility, and at a site downstream of the facility. Mortality was significantly less at a nearby reference stream and at a station in the tidal area of Zekiah Swamp Run. Analysis of water samples for metals (including inorganic monomeric aluminum), organic contaminants, and pH, as well as measurements of stream flow, did not identify a specific cause for the mortality. The field and laboratory bioassays showed that, although leachate from the ash facility contributed to local contamination of ground water, the facility does not appear to be responsible for the poor survival of larval yellow perch. 16 refs., 4 figs., 6 tabs

  13. Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield

    Science.gov (United States)

    Gabriel, M.C.; Kolka, R.; Wickman, T.; Nater, E.; Woodruff, Laurel G.

    2009-01-01

    The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO3−-N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman ρ = 0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r = 0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r2 = 0.73, with an overall 10 ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem.

  14. Concentrations of 17 elements in the zebra mussel (Dreissena polymorpha), in different tissues of perch (Perca fluviatilis), and in perch intestinal parasites (Acanthocephalus lucii) from the subalpine lake Mondsee, Austria

    Energy Technology Data Exchange (ETDEWEB)

    Sures, B.; Steiner, W.; Rydlo, M.; Taraschewski, H.

    1999-11-01

    Concentrations of the elements Al, Ag, Ba, ca, Cd, Co, Cr, cu, Fe, Ga, Mg, Mn, Ni, Pb, Sr, Tl, and Zn were analyzed by inductively coupled plasma mass spectrometry in the acanthocephalan Acanthocephalus lucii (Mueller); in its host, Perca fluviatilis (L.), and in the soft tissue of the zebra mussel, Dreissena polymorpha (Pallas). All animals were collected from the same sampling site in a subalpine lake, Mondsee, in Austria. Most of the elements were found at significantly higher concentrations in the acanthocephalan than in different tissues (muscle, liver, and intestinal wall) of its perch host. Only Co was concentrated in the liver of perch to a level that was significantly higher than that found in the parasite. Most of the analyzed elements were also present at significantly higher concentrations in A. lucii than in D. polymorpha. Barium and Cr were the only elements recorded at higher concentrations in the mussel compared with the acanthocephalan. Thus, when comparing the accumulation of elements, the acanthocephalans appear to be even more suitable than the zebra mussels in terms of their use in the detection of metal contamination within aquatic biotopes. Spearman correlation analysis revealed that the concentrations of several elements within the parasites decreased with increasing infrapopulation. Furthermore, the levels of some elements in the perch liver were negatively correlated with the weight of A. lucii in the intestine. Thus, it emerged that not only is there competition for elements between acanthocephalans inside the gut but there is also competition for these elements between the host and the parasites. The elevated element concentrations demonstrated here in the parasitic worm A. lucii provide support for further investigations of these common helminthes and of their accumulation properties.

  15. Radiological investigation of roach and perch from some lakes in Lithuania

    International Nuclear Information System (INIS)

    Cepanko, V.; Idzelis, R. L.; Kesminas, V.; Lydagiene, R.

    2006-01-01

    From the point of view of biological toxicity the most toxic radionuclides are man-made 90 Sr and 137 Cs because the behaviour of both of them is similar to stable calcium and potassium in the body. Fish is the last part of the hydro system chain which accumulates pollutants. The aim of this study was to analyse the distribution of these two radionuclides in the muscle and other organs of perch and roach that differ by age and living conditions. Measurements were performed for 137 Cs and 90 Sr activity concentrations in fishes from the lakes of Druksiai, Lukstas and Dusia. Radioecological investigation was carried out for different age groups of roach and perch analysing samples of muscle and spine bones (including the head of fish). Radioecological investigation of fishes from the lakes of Druksiai, Lukstas and Dusia show that the activity concentrations of 137 Cs and 90 Sr are low. Anyway, the accumulated radioactivity by food chain reaches the human body. Nowadays a lot of investigations are related to the lakes in the vicinity of Ignalina NPP. The investigation shows that the activity concentrations of 137 Cs and 90 Sr in fishes from the Druksiai lake are the same as in fishes from other lakes in other locations of Lithuania. (author)

  16. Comparison of nutritional quality in fish maw product of croaker Protonibea diacanthus and perch Lates niloticus

    Science.gov (United States)

    Wen, Jing; Zeng, Ling; Chen, Ziming; Xu, Youhou

    2016-08-01

    Fish maw (the dried swimbladders of fish) is ranked in the list of the four sea treasures in Chinese cuisine. Fish maw is mainly produced from croaker, which is the most highly priced. However, some of the fish maw being sold as croaker maw are in fact not from croaker, but from the Nile perch Lates niloticus. The present work determined and compared the proximate composition, amino acid and fatty acid composition of croaker Protonibea diacanthus maw and perch L. niloticus maw. The results indicated that both maws were high protein sources and low in fat content. The dominant amino acids in both maws were glycine, proline, glutamic acid, alanine and arginine. These amino acids constituted 66.2% and 66.4% of the total amino acids in P. diacanthus and L. niloticus, respectively. The ratio of FAA: TAA (functional amino acids: total amino acids) in both maws were 0.69. This is a good explanation for why fish maws have been widely utilized as a traditional tonic and remedy in Asia. Except valine and histidine, all the essential amino acid contents in P. diacanthus were higher than in L. niloticus. Moreover, croaker P. diacanthus maw contained more AA and DHA than perch L. niloticus maw, showing a higher ratio of n-3 / n-6, which is more desirable.

  17. Factors Influencing of Social Conflict

    Directory of Open Access Journals (Sweden)

    Suwandi Sumartias

    2013-07-01

    Full Text Available Social conflicts that occur in several areas in Indonesia lately, one of them is caused by the weakness of law certainty. This is feared to threaten the integration of the Republic of Indonesia. This study aims to determine the factors that affect social conflict in Manis Lor village in Kuningan district. The method used the explanatory quantitative methods, the statistical test Path Analysis. The study population was a formal and informal community leaders (village chief, clergy, and youth, and the people who involved in a conflict in Manis Lor village Kuningan regency. The result shows a There is no significant influence between social identity factors with social conflict anarchist. b There is significant influence between socio-economic factors with social conflict anarchists. c There is no significant influence between the credibility factor anarchist leaders with social conflict. d There is no significant influence between the motive factor with anarchist social conflict. e There is significant influence between personality factors/beliefs with anarchist social conflict. f There is significant influence of behavioral factors anarchist communication with social conflict.

  18. Approaches to the simulation of unconfined flow and perched groundwater flow in MODFLOW

    Science.gov (United States)

    Bedekar, Vivek; Niswonger, Richard G.; Kipp, Kenneth; Panday, Sorab; Tonkin, Matthew

    2012-01-01

    Various approaches have been proposed to manage the nonlinearities associated with the unconfined flow equation and to simulate perched groundwater conditions using the MODFLOW family of codes. The approaches comprise a variety of numerical techniques to prevent dry cells from becoming inactive and to achieve a stable solution focused on formulations of the unconfined, partially-saturated, groundwater flow equation. Keeping dry cells active avoids a discontinuous head solution which in turn improves the effectiveness of parameter estimation software that relies on continuous derivatives. Most approaches implement an upstream weighting of intercell conductance and Newton-Raphson linearization to obtain robust convergence. In this study, several published approaches were implemented in a stepwise manner into MODFLOW for comparative analysis. First, a comparative analysis of the methods is presented using synthetic examples that create convergence issues or difficulty in handling perched conditions with the more common dry-cell simulation capabilities of MODFLOW. Next, a field-scale three-dimensional simulation is presented to examine the stability and performance of the discussed approaches in larger, practical, simulation settings.

  19. Seasonal variations in hepatic Cd and Cu concentrations and in the sub-cellular distribution of these metals in juvenile yellow perch (Perca flavescens)

    International Nuclear Information System (INIS)

    Kraemer, Lisa D.; Campbell, Peter G.C.; Hare, Landis

    2006-01-01

    Temporal fluctuations in metal (Cd and Cu) concentrations were monitored over four months (May to August) in the liver of juvenile yellow perch (Perca flavescens) sampled from four lakes situated along a metal concentration gradient in northwestern Quebec: Lake Opasatica (reference lake, low metal concentrations), Lake Vaudray (moderate metal concentrations) and lakes Osisko and Dufault (high metal levels). The objectives of this study were to determine if hepatic metal concentrations and metal-handling strategies at the sub-cellular level varied seasonally. Our results showed that Cd and Cu concentrations varied most, in both absolute and relative values, in fish with the highest hepatic metal concentrations, whereas fish sampled from the reference lake did not show any significant variation. To examine the sub-cellular partitioning of these two metals, we used a differential centrifugation technique that allowed the separation of cellular debris, metal detoxified fractions (heat-stable proteins such as metallothionein) and metal sensitive fractions (heat-denaturable proteins (HDP) and organelles). Whereas Cd concentrations in organelle and HDP fractions were maintained at low concentrations in perch from Lakes Opasatica and Vaudray, concentrations in these sensitive fractions were higher and more variable in perch from Lakes Dufault and Osisko, suggesting that there may be some liver dysfunction in these two fish populations. Similarly, Cu concentrations in these sensitive fractions were higher and more variable in perch from the two most Cu-contaminated lakes (Dufault and Osisko) than in perch from the other two lakes, suggesting a breakdown of homeostatic control over this metal. These results suggest not only that metal concentrations vary seasonally, but also that concentrations vary most in fish from contaminated sites. Furthermore, at the sub-cellular level, homeostatic control of metal concentrations in metal-sensitive fractions is difficult to maintain in

  20. Extraction and Production of Omega-3 from UniMAP Puyu (Jade Perch) and Mackarel

    Science.gov (United States)

    Nur Izzati, I.; Zainab, H.; Nornadhiratulhusna, M.; Chee Hann, Y.; Khairunissa Syairah, A. S.; Amira Farzana, S.

    2018-03-01

    Extraction techniques to extract fish oil from various types of fish are numerous but not widely accepted because of the use of chemicals that may be harmful to health. In this study, fish oil is extracted using a technique of Microwave-Assisted Extraction, which uses only water. The optimum conditions required for the production of fish oil for extraction is carried out by examining three parameters such as microwave power (300-700W), extraction time (10-30 min) and amount of water used (70-190ml). Optimum conditions were determined after using design of experiments (DOE). The optimum condition obtained was 300 W for microwave power, 10 minutes extraction time and 190 milliliter amounts of water used. Fourier transform infrared spectroscopy (FTIR) was used to analyze the functional groups of fish oil. Two types of fish such as Jade Perch or UniMAP Puyu and Indian Mackerel were used. A standard omega-3 oil sample (Blackmores) purchased from pharmacy was also determined to confirm the presence of omega-3 oil in these fishes. Similar compounds were present in Jade Perch and Indian Mackerel as compared to the standard. Therefore, there were presence of omega-3 fish oil in the two types of fish. From this study, omega-3 in UniMAP Puyu fish was higher compared to Indian Mackerel fish. However, based on the FTIR analysis, besides the presence of omega-3, the two fishes also contain other functional groups such as alkanes, alkenes, aldehyde, ketones and many others. The yield of fish oil for the Jade Perch was low compared to Indian Mackerel which was 9% while Indian Mackerel was 10 %.

  1. Echolocation intensity and directionality of perching and flying fringe-lipped bats, Trachops cirrhosus (Phyllostomidae)

    DEFF Research Database (Denmark)

    Surlykke, Annemarie; Jakobsen, Lasse; Kalko, Elisabeth K V

    2013-01-01

    The Neotropical frog-eating bat, Trachops cirrhosus, primarily hunts stationary prey, either by gleaning on the wing, or in a sit-and-wait mode hanging from a perch. It listens passively for prey-generated sounds, but uses echolocation in all stages of the hunt. Like other bats in the family...

  2. Cadmium-handling strategies in two chronically exposed indigenous freshwater organisms-the yellow perch (Perca flavescens) and the floater mollusc (Pyganodon grandis)

    International Nuclear Information System (INIS)

    Campbell, Peter G.C.; Giguere, Anik; Bonneris, Emmanuelle; Hare, Landis

    2005-01-01

    Laboratory experiments on a variety of aquatic organisms suggest that metallothionein-like proteins (MT) play an important role in the regulation of essential metals, and in the sequestration and detoxification of non-essential metals (e.g., Cd). However, the importance of metallothionein production relative to alternative strategies of metal detoxification, and its effectiveness in metal detoxification, remain largely unexplored in field situations. In the present study we explored metal-handling strategies in an adult benthic bivalve (Pyganodon grandis) and in juvenile yellow perch (Perca flavescens), exposed to Cd in their natural habitat. The two biomonitor species were collected from lakes located along a Cd concentration gradient. Ambient dissolved Cd concentrations were determined by in situ dialysis as a measure of metal exposure. Sub-cellular Cd partitioning was determined in target tissues (bivalve gills and digestive gland; perch liver) by differential centrifugation, and metallothionein was measured independently by a mercury-saturation assay in the bivalve tissues. Malondialdehyde concentrations were measured as a potential indicator of oxidative stress. Ambient dissolved Cd concentrations ranged from 0.06 to 0.57 nM in the nine lakes from which bivalves were collected, and from max /[Cd] min ratios for the various tissues decreased in the order: bivalve gill Cd (28) > bivalve digestive gland Cd (18) > perch hepatic Cd (14). In the two lakes that were common to both the bivalve and perch studies, i.e. lakes Opasatica and Vaudray, accumulated Cd concentrations were consistently higher in the bivalve than in the perch. Cadmium-handling strategies were similar in the bivalve digestive gland and perch liver, in that Cd was mainly associated with the heat-stable protein (HSP) fraction. Furthermore, in these organs the contributions from the 'mitochondria' and 'lysosomes + microsomes' fractions were consistently higher than in the gill tissue. In the bivalve

  3. Transmission Electron Microscopy of the Gastrointestinal Tract of Nile Perch Lates niloticus

    OpenAIRE

    Namulawa, V. T; Kato, C. D; Nyatia, E; Rutaisire, J; Britz, P. J

    2015-01-01

    The ultrastructure of the gastrointestinal tract of Nile perch was described using Transmission Electron Microscopy standard procedures. Investigations revealed the presence of mucous cells, blood vessels and oil droplets plus several nerve cells and muscle bundles in the oral cavity. Further observations revealed columnar epithelial cells in the oesophagus, with a ragged surface, high electron dense cytoplasm, intercellular spaces, mitochondria and mucus granules. The lamina propria of the o...

  4. Metabolic and thyroidal response in air-breathing perch (Anabus testudineus) to water-borne kerosene

    NARCIS (Netherlands)

    Peter, V.S.; Joshua, E.K.; Wendelaar Bonga, S.E.; Peter, M.C.S.

    2007-01-01

    To address the physiological compensatory adaptations in air-breathing fish to a toxicant, we studied the metabolite pattern, serum and liver enzymes and thyroidal response in a tropical air-breathing perch, Anabas testudineus (kept at 30 _C in a 12-h L:D cycle) after exposing the fish for 48 h to

  5. Molecular identification of a yellow perch viral disease associated with exposure to oil sands process affected waters

    International Nuclear Information System (INIS)

    Hogan, N.; Van den Heuvel, M.; Phalen, L.

    2010-01-01

    Large volumes of tailings and process affected water are generated as a result of oil sand mining processes. This presentation discussed the safe incorporation of these wastes into the terrestrial and aquatic landscape. A study was conducted in which yellow perch were stocked into experimental ponds, namely Demonstration Pond and South Bison Pond, during the periods of 1995-1997 and 2008-2010. Demonstration Pond was comprised of mature fine tailings capped with natural surface water, while South Bison Pond was formed at a site surrounded by overburden or lean oil sands. Disease surveys were conducted at these experimental ponds and also at Mildred, Sucker, and Kimowin Lakes. External white nodular lesions, characteristic of lymphocystis disease were observed on perch at all sites except Kimowin Lake. The identity of the virus was confirmed by DNA extraction and PCR with genotype generic major capsid protein gene primers. The presence of lymphocystis disease virus in perch was confirmed through sequencing of PCR results. The viral genotype appeared to be different from any previously isolated viral genotype. During the course of the study, there was an increasing incidence of the disease at Demonstration Pond and a decreasing incidence at the South Bison Pond. The intensity of the disease was found to be proportional to the incidence, which was positively correlated with changes in naphthenic acid concentration.

  6. Hanging out at the airport: Unusual upside-down perching behavior by Eurasian Jackdaws (Corvus monedula) in a human-dominated environment

    Science.gov (United States)

    Katzner, Todd E.

    2016-01-01

    Animals occupying human-dominated environments show the capacity for behavioral flexibility. Corvids are among the most intelligent synanthropic bird species. During a layover at Schipol Airport in Amsterdam, Netherlands, I photographically documented Eurasian Jackdaws (Corvus monedula) perching upside down from a building cornice. In contrast to other reports of hanging birds, these jackdaws did not forage or play while upside down and appeared to use the perching spot to observe their surroundings. Although Corvids and Psittacines are known to hang upside down, especially in captive situations, such behaviors are rarely documented in the wild, and never before in association with human-built structures.

  7. Use of sleeping perches by the lizard Anolis uniformis (Squamata: Polychrotidae in the fragmented tropical rainforest at Los Tuxtlas, Mexico Uso de perchas para dormir por la lagartija Anolis uniformis (Squamata: Polychrotidae en el bosque tropical fragmentado de Los Tuxtlas, México

    Directory of Open Access Journals (Sweden)

    Elisa Cabrera-Guzmán

    2010-12-01

    Full Text Available The use of nocturnal perches by the lizard Anolis uniformis is described. Bimonthly surveys were made throughout a year in small fragments and continuous tropical rainforest areas at Los Tuxtlas, Mexico. Twenty three juvenile individuals and 7 adults were recorded sleeping during the sampling time (18:00 - 23:00 h.. All individuals were found on leaves of plants of 14 species. Perch height ranged from 41.0 to 140.5 cm (mean: 90.1 cm juveniles; 80.6 cm adults and the most frequent sleeping position observed was with the body oriented along the longitudinal axis of the leaf and the head facing the stem of the plant. This apparently vulnerable position can permit the perception of external stimuli such as proximity of predators; although, eco-physiological factors may also influence selection of sleeping perch sites.Se describe el uso de perchas nocturnas por parte de la lagartija Anolis uniformis. Durante un año se ralizaron muestreos bimensuales en fragmentos pequeños y áreas continuas de bosque tropical perennifolio en Los Tuxtlas, México. Se registraron 23 individuos juveniles y 7 adultos durmiendo durante las horas de muestreo (18:00 a 23:00 hrs. Todos los individuos fueron encontrados en hojas de plantas pertenecientes a 14 especies. La altura de las perchas varió entre 41.0 y 140.5 cm (promedio: 90.1 cm juveniles; 80.6 cm adultos y la posición más frecuente de las lagartijas al dormir fue con el cuerpo extendido a lo largo del eje longitudinal de la hoja y la cabeza dirigida hacia el tallo de la planta. Esta posición, aparentemente vulnerable, puede permitir la percepción de estímulos externos como la aproximación de depredadores; sin embargo, factores eco-fisiológicos pueden también influir en la selección de sitios para dormir.

  8. Prolonged air-breathing and recovery modify the thyroid and interrenal axes in climbing perch (Anabas testudineus)

    NARCIS (Netherlands)

    Peter, M.C.S.; Wendelaar Bonga, S.E.

    2007-01-01

    To examine the response of thyroid and intrenal axes to hydromineral and metabolic responses in air-breathing fish during their territorial migration, we quantified several physiological markers in the tropical obligate air-breathing perch (Anabas testudineus) during air breathing on land and in

  9. Effects of turbidity and prey density on the foraging success of age 0 year yellow perch Perca flavescens.

    Science.gov (United States)

    Wellington, C G; Mayer, C M; Bossenbroek, J M; Stroh, N A

    2010-05-01

    Laboratory experiments were conducted to determine how larval and juvenile yellow perch Perca flavescens respond to changes in prey density when exposed to different levels and types of turbidity (phytoplanktonic or sedimentary). Across prey densities, consumption by P. flavescens tended to be less in phytoplanktonic turbidity compared with sedimentary turbidity. For larvae, this effect was dependent on turbidity level (consumption differed between turbidity types only at high turbidity), while for juveniles the difference with turbidity type was equal across turbidity levels. These results suggest that phytoplankton blooms are detrimental to the ability of late season age 0 year P. flavescens to forage and support the need to control factors leading to excessive phytoplankton growth in lakes.

  10. Application of HEC-RAS for flood forecasting in perched river-A case study of hilly region, China

    Science.gov (United States)

    Sun, Pingping; Wang, Shuqian; Gan, Hong; Liu, Bin; Jia, Ling

    2017-04-01

    Flooding in small and medium rivers are seriously threatening the safety of human beings’ life and property. The simulation forecasting of the river flood and bank risk in hilly region has gradually become a hotspot. At present, there are few studies on the simulation of hilly perched river, especially in the case of lacking section flow data. And the method of how to determine the position of the levee breach along the river bank is not much enough. Based on the characteristics of the sections in hilly perched river, an attempt is applied in this paper which establishes the correlation between the flow profile computed by HEC-RAS model and the river bank. A hilly perched river in Lingshi County, Shanxi Province of China, is taken as the study object, the levee breach positions along the bank are simulated under four different design storm. The results show that the flood control standard of upper reach is high, which can withstand the design storm of 100 years. The current standard of lower reach is low, which is the flooding channel with high frequency. As the standard of current channel between the 2rd and the 11th section is low, levee along that channel of the river bank is considered to be heighten and reinforced. The study results can provide some technical support for flood proofing in hilly region and some reference for the reinforcement of river bank.

  11. Human factors influencing decision making

    OpenAIRE

    Jacobs, Patricia A.

    1998-01-01

    This report supplies references and comments on literature that identifies human factors influencing decision making, particularly military decision making. The literature has been classified as follows (the classes are not mutually exclusive): features of human information processing; decision making models which are not mathematical models but rather are descriptive; non- personality factors influencing decision making; national characteristics influencing decision makin...

  12. Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. II: live weight, health measures and perching.

    Science.gov (United States)

    Steenfeldt, S; Nielsen, B L

    2015-09-01

    Multi-tier aviary systems, where conveyor belts below the tiers remove the manure at regular intervals, are becoming more common in organic egg production. The area on the tiers can be included in the net area available to the hens (also referred to as usable area) when calculating maximum indoor stocking densities in organic systems within the EU. In this article, results on live weight, health measures and perching are reported for organic laying hens housed in a multi-tier system with permanent access to a veranda and kept at stocking densities (D) of 6, 9 and 12 hens/m2 available floor area, with concomitant increases in the number of hens per trough, drinker, perch and nest space. In a fourth treatment, access to the top tier was blocked reducing vertical, trough, and perch access at the lowest stocking density (D6x). In all other aspects than stocking density, the experiment followed the EU regulations on the keeping of organic laying hens. Hen live weight, mortality and foot health were not affected by the stocking densities used in the present study. Other variables (plumage condition, presence of breast redness and blisters, pecked tail feathers, and perch use) were indirectly affected by the increase in stocking density through the simultaneous reduction in access to other resources, mainly perches and troughs. The welfare of the hens was mostly affected by these associated constraints, despite all of them being within the allowed minimum requirements for organic production in the EU. Although the welfare consequences reported here were assessed to be moderate to minor, it is important to take into account concurrent constraints on access to other resources when higher stocking densities are used in organic production.

  13. Before-after, control-impact analysis of evidence for the impacts of water level on Walleye, Northern Pike and Yellow Perch in lakes of the Rainy-Namakan complex (MN, USA and ON, CA.

    Directory of Open Access Journals (Sweden)

    James H Larson

    Full Text Available Water level (WL fluctuations in lakes influence many aspects of ecosystem processes. Concern about the potential impact of WL fluctuations on fisheries was one of the factors that motivated the decision in 2000 to alter the management of WL in the Rainy-Namakan reservoir complex (on the border between the U.S. state of Minnesota and the Canadian province of Ontario. We used a Before-After, Control-Impact (BACI framework to identify potential impacts of the change in WL management to Walleye, Northern Pike and Yellow Perch catch per unit effort (CPUE. The CPUE of these species from 1990-1999 and from 2005-2014 were compared in four impact lakes (Lake Kabetogama, Namakan Lake, Rainy Lake and Sand Point Lake and two control lakes (Lake of the Woods and Lake Vermilion using a simple Bayesian model. Changes in fish CPUE in the impact lakes were often similar to changes that occurred in at least one control lake. The only change that was not similar to changes in control lakes was an increase of Yellow Perch in Lake Kabetogama. The two control lakes often differed substantially from each other, such that if only one had been available our conclusions about the role of WL management on fisheries would be very different. In general, identifying cause-and-effect relationships in observational field data is very difficult, and the BACI analysis used here does not specify a causative mechanism, so co-occurring environmental and management changes may obscure the effect of WL management.

  14. [Natural factors influencing sleep].

    Science.gov (United States)

    Jurkowski, Marek K; Bobek-Billewicz, Barbara

    2007-01-01

    Sleep is a universal phenomenon of human and animal lives, although the importance of sleep for homeo-stasis is still unknown. Sleep disturbances influence many behavioral and physiologic processes, leading to health complications including death. On the other hand, sleep improvement can beneficially influence the course of healing of many disorders and can be a prognostic of health recovery. The factors influencing sleep have different biological and chemical origins. They are classical hormones, hypothalamic releasing and inhibitory hormones, neuropeptides, peptides and others as cytokines, prostaglandins, oleamid, adenosine, nitric oxide. These factors regulate most physiologic processes and are likely elements integrating sleep with physiology and physiology with sleep in health and disorders.

  15. Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield

    Science.gov (United States)

    Mark C. Gabriel; Randy Kolka; Trent Wickman; Ed Nater; Laurel. Woodruff

    2009-01-01

    The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue...

  16. Theoretical difference between impact factor and influence factor

    Directory of Open Access Journals (Sweden)

    Đilda Pečarić

    2010-06-01

    Full Text Available Bibliometric constructions of "knowledge maps" and "cognitive structures of science" do not differentiate between impact and influence factors. The difference can be constructedaccording to different meaning and interpretation of the terms reference and citation. Reference is "acknowledgment which one author gives to another", whereas citation is "acknowledgment which one document receives from another". Development of Information Science according to period and subject area is analyzed on the corpus of citation literature retrieved from doctoral dissertations in Information Science from 1978 to 2007 at Croatian universities. The research aim is to indicate the difference between document impact factor and author's influence factor (i.e. reference ability to produce effects on actions, behavior, and opinions of authors of doctoral theses. The influence factor serves to distinguish the key role of cited authors in time and according to the duration of the influence (the average age for cited papers of dominant authors in different periods is between eight and ten years. The difference between linear and interactive communication seems vital for the interpretation of cited half-life, i.e. the attitude of one science community towards used information resources and cognitive heritage. The analyzed corpus of 22,210 citations can be divided into three communication phases according to influence factor criteria: in the phase of dialogue and interactive communication 25% of bibliographic units are cited in the first four years; in the second phase another 25% of units are cited from the fifth to the ninth year; after ten years, in the dominant linear communication phase, approximately 30% of units are cited.

  17. An update of hydrologic conditions and distribution of selected constituents in water, eastern Snake River Plain aquifer and perched groundwater zones, Idaho National Laboratory, Idaho, emphasis 2012-15

    Science.gov (United States)

    Bartholomay, Roy C.; Maimer, Neil V.; Rattray, Gordon W.; Fisher, Jason C.

    2017-04-10

    Since 1952, wastewater discharged to in ltration ponds (also called percolation ponds) and disposal wells at the Idaho National Laboratory (INL) has affected water quality in the eastern Snake River Plain (ESRP) aquifer and perched groundwater zones underlying the INL. The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, maintains groundwater-monitoring networks at the INL to determine hydrologic trends and to delineate the movement of radiochemical and chemical wastes in the aquifer and in perched groundwater zones. This report presents an analysis of water-level and water-quality data collected from the ESRP aquifer, multilevel monitoring system (MLMS) wells in the ESRP aquifer, and perched groundwater wells in the USGS groundwater monitoring networks during 2012-15.

  18. Conceptual Layout of Wing Structure Using Topology Optimization for Morphing Micro Air Vehicles in a Perching Maneuver

    Science.gov (United States)

    2012-03-22

    back out both to quickly ascend and to collect momentum -reducing drag. A few points along the perching trajectory will be extracted which are...derivation follows classical Kirchhoff plate theory (2D extension of Euler- Bernoulli beam theory). When minimizing a structure’s compli- ance, which is

  19. Demotivating factors influencing rubber production workers

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Iravani

    2012-01-01

    Full Text Available Motivation is one of the most important factors influencing workers' productivity. An increase in workers' motivation could add more value to organizations' structure and influence the profitability, significantly. In this paper, we study different factors on demotivating workers using questionnaire consist of various questions. The questionnaire is distributed among some employees who work for rubber production units located in Esfahan, Iran. The results of this survey indicate that discrimination on annual job compensation, entrusting responsibilities and unpleasant relationship with family partner are some of the most important factors influencing employees' motivation. While financial factors play important role on increasing employees' motivation, non-financial factors are considered more important.

  20. Factors influencing women's decisions to purchase specific ...

    African Journals Online (AJOL)

    aimed at identifying the factors that influence women's decisions to purchase specific .... influence of all the factors influencing their decision to purchase a selected .... one free” promotions seemed to have had the greatest influence on this ...

  1. On the suitability of roach, perch, vendace and whitefish for canning in small scale canning stations

    Directory of Open Access Journals (Sweden)

    Mailis Kuuppo

    1978-07-01

    Full Text Available The suitability of roach (Rutilus rutilus, perch (Perca fluviatilis, vendace (Coregonus albula L., and whitefish (Coregonus sp. for canning in small scale canning stations was tested. Various pretreatment methods and processing conditions were evaluated for different fish species. Processing equipment suitable for small scale canning stations was developed in the course of this study. The keepability of the canned products was followed by physical, organoleptic and microbiological determinations during a period of 18 months. The roach, vendace and whitefish preserves were of the types »canned fish in tomato sauce» and »canned fish in oil and its own juice» and the perch preserves of the type »canned fish in brine». Roach, vendace and whitefish were salted by immersing into 21 % brine for 4—25 minutes depending on the size of the fish and preheated by smoking at 90° C for 60 —120 minutes. Products of good quality were obtained from whitefish which was dried by cooking in oil at 120 °C for 3 minutes instead of smoking. The perch were cooked in 3 % and 4 % brine for 15—20 minutes depending on the size of the fish. The best time and temperature combination for the aimed F value 10 and for a product of good quality was 60 minutes at 115°C when using rotation. In organoleptic evaluation all the canned products were judged to be of good quality and there were no significant changes in appearance, texture, taste or aroma during 18 months' storage at room temperature. No microbial growth or swelling of the cans was detected during storage. Use of frozen raw material in canning whitefish had no detectable effect on the quality of the final product.

  2. Comparison of food habits of white perch (Morone americana) in the heated effluent canal of a steam electric station and in an adjacent river system

    International Nuclear Information System (INIS)

    Moore, C.J.; Fuller, S.L.H.; Burton, D.T.

    1975-01-01

    Analysis of the stomach contents of 97 white perch, Morone americana, taken from the effluent canal of a steam electric station (S.E.S.) and 106 white perch from adjacent Patuxent River waters indicated similar food habits from September 1970 through August 1971. However, 35 percent of all white perch taken from the heated effluent canal contained small pieces of coal and cinders, whereas only 3 percent of the river specimens contained such items in their stomachs. Fly ash and coal dust are present on the bottom of the S.E.S. canal, whereas little such material, if any, can be found on the river bottom in the study area. This suggests the canal fish were actively feeding in the heated effluent and not simply moving into the canal after feeding in the river. No significant difference (P greater than 0.05) was found between the average wet weight stomach contents of the river and canal fish within the same month

  3. Hydrogeological and geochemical studies in the Perch Lake basin

    International Nuclear Information System (INIS)

    Barry, P.J.

    1979-08-01

    The Perch Lake basin is a small drainage system along the Ottawa River about 200 km west of Ottawa on the Canadian Shield. Since 1975, groups of scientists from several Canadian universities and government departments have been studying the hydrological, geological and geochemical properties of the basin. The object of these studies is to develop and test simulation models used to describe the time-dependent mass flow rates of water and dissolved and suspended substances through the basin. To review progress, a symposium/workshop was held at Chalk Rier in 1978 April. This report contains 24 extended summaries of the material presented verbally at the workshop. Subject matters include atmospheric sources and sinks, mass flows through the surface and subsurface regimes in the drainage basins and interactions occurring in the lake. (author)

  4. Timing, frequency and environmental conditions associated with mainstem-tributary movement by a lowland river fish, golden perch (Macquaria ambigua.

    Directory of Open Access Journals (Sweden)

    Wayne M Koster

    Full Text Available Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007-2011. Fish were tagged and released in autumn 2007-2009 in the mid-Murray (n = 42 and lower Goulburn (n = 37 rivers within 3-6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem-tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem-tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers.

  5. Timing, frequency and environmental conditions associated with mainstem-tributary movement by a lowland river fish, golden perch (Macquaria ambigua).

    Science.gov (United States)

    Koster, Wayne M; Dawson, David R; O'Mahony, Damien J; Moloney, Paul D; Crook, David A

    2014-01-01

    Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua) between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007-2011). Fish were tagged and released in autumn 2007-2009 in the mid-Murray (n = 42) and lower Goulburn (n = 37) rivers within 3-6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem-tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem-tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers.

  6. Timing, Frequency and Environmental Conditions Associated with Mainstem–Tributary Movement by a Lowland River Fish, Golden Perch (Macquaria ambigua)

    Science.gov (United States)

    Koster, Wayne M.; Dawson, David R.; O’Mahony, Damien J.; Moloney, Paul D.; Crook, David A.

    2014-01-01

    Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua) between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007–2011). Fish were tagged and released in autumn 2007–2009 in the mid-Murray (n = 42) and lower Goulburn (n = 37) rivers within 3–6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem–tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem–tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers. PMID:24788137

  7. Physical Health Problems and Environmental Challenges Influence Balancing Behaviour in Laying Hens.

    Directory of Open Access Journals (Sweden)

    Stephanie LeBlanc

    Full Text Available With rising public concern for animal welfare, many major food chains and restaurants are changing their policies, strictly buying their eggs from non-cage producers. However, with the additional space in these cage-free systems to perform natural behaviours and movements comes the risk of injury. We evaluated the ability to maintain balance in adult laying hens with health problems (footpad dermatitis, keel damage, poor wing feather cover; n = 15 using a series of environmental challenges and compared such abilities with those of healthy birds (n = 5. Environmental challenges consisted of visual and spatial constraints, created using a head mask, perch obstacles, and static and swaying perch states. We hypothesized that perch movement, environmental challenges, and diminished physical health would negatively impact perching performance demonstrated as balance (as measured by time spent on perch and by number of falls of the perch and would require more exaggerated correctional movements. We measured perching stability whereby each bird underwent eight 30-second trials on a static and swaying perch: with and without disrupted vision (head mask, with and without space limitations (obstacles and combinations thereof. Video recordings (600 Hz and a three-axis accelerometer/gyroscope (100 Hz were used to measure the number of jumps/falls, latencies to leave the perch, as well as magnitude and direction of both linear and rotational balance-correcting movements. Laying hens with and without physical health problems, in both challenged and unchallenged environments, managed to perch and remain off the ground. We attribute this capacity to our training of the birds. Environmental challenges and physical state had an effect on the use of accelerations and rotations to stabilize themselves on a perch. Birds with physical health problems performed a higher frequency of rotational corrections to keep the body centered over the perch, whereas, for both

  8. Physical Health Problems and Environmental Challenges Influence Balancing Behaviour in Laying Hens.

    Science.gov (United States)

    LeBlanc, Stephanie; Tobalske, Bret; Quinton, Margaret; Springthorpe, Dwight; Szkotnicki, Bill; Wuerbel, Hanno; Harlander-Matauschek, Alexandra

    2016-01-01

    With rising public concern for animal welfare, many major food chains and restaurants are changing their policies, strictly buying their eggs from non-cage producers. However, with the additional space in these cage-free systems to perform natural behaviours and movements comes the risk of injury. We evaluated the ability to maintain balance in adult laying hens with health problems (footpad dermatitis, keel damage, poor wing feather cover; n = 15) using a series of environmental challenges and compared such abilities with those of healthy birds (n = 5). Environmental challenges consisted of visual and spatial constraints, created using a head mask, perch obstacles, and static and swaying perch states. We hypothesized that perch movement, environmental challenges, and diminished physical health would negatively impact perching performance demonstrated as balance (as measured by time spent on perch and by number of falls of the perch) and would require more exaggerated correctional movements. We measured perching stability whereby each bird underwent eight 30-second trials on a static and swaying perch: with and without disrupted vision (head mask), with and without space limitations (obstacles) and combinations thereof. Video recordings (600 Hz) and a three-axis accelerometer/gyroscope (100 Hz) were used to measure the number of jumps/falls, latencies to leave the perch, as well as magnitude and direction of both linear and rotational balance-correcting movements. Laying hens with and without physical health problems, in both challenged and unchallenged environments, managed to perch and remain off the ground. We attribute this capacity to our training of the birds. Environmental challenges and physical state had an effect on the use of accelerations and rotations to stabilize themselves on a perch. Birds with physical health problems performed a higher frequency of rotational corrections to keep the body centered over the perch, whereas, for both health categories

  9. Factors Influencing Substance Abuse among Undergraduate ...

    African Journals Online (AJOL)

    The study investigated the factors influencing substance abuse amongundergraduate students in Osun State; Nigeria. A sample of 1, 200undergraduate students were randomly selected from three tertiaryinstitution in Osun State. Factors Influencing Substance Abuse Questionnaire (FISA) was developed by the researcher ...

  10. FACTORS INFLUENCING THE EVOLUTION OF YOUTH TRAVEL

    Directory of Open Access Journals (Sweden)

    Student Claudia MOISĂ

    2010-01-01

    Full Text Available Youth travel is an important part of global tourism, consequently, getting to know the evolution of this form of tourism requires an approach of the aspects regarding the permissive and restrictive factors that influence the youth travel dynamic worldwide. In terms of the factors that influence youth travel, we highlighted these two categories of factors (permissive and restrictive and, within each category, we tried to singularize the influence of every factor over youth travel.

  11. A multi-level biological approach to evaluate impacts of a major municipal effluent in wild St. Lawrence River yellow perch (Perca flavescens)

    Energy Technology Data Exchange (ETDEWEB)

    Houde, Magali, E-mail: magali.houde@ec.gc.ca [Centre Saint-Laurent, Environment Canada, 105 McGill Street, Montreal, QC H2Y 2E7 (Canada); Giraudo, Maeva, E-mail: maeva.giraudo@ec.gc.ca [Centre Saint-Laurent, Environment Canada, 105 McGill Street, Montreal, QC H2Y 2E7 (Canada); Douville, Mélanie, E-mail: melanie.douville@ec.gc.ca [Centre Saint-Laurent, Environment Canada, 105 McGill Street, Montreal, QC H2Y 2E7 (Canada); Bougas, Bérénice, E-mail: berenice.bougas.1@ulaval.ca [Institut de biologie intégrative et des systèmes, Université Laval, 1030, avenue de la Médecine, Québec, QC G1V 0A6 (Canada); Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre Eau Terre Environnement, 490 de la Couronne, Québec, QC G1K 9A9 (Canada); De Silva, Amila O., E-mail: amila.desilva@ec.gc.ca [Canada Centre for Inland Waters, Environment Canada, 867 Lakeshore Road, P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Spencer, Christine, E-mail: christine.spencer@ec.gc.ca [Canada Centre for Inland Waters, Environment Canada, 867 Lakeshore Road, P.O. Box 5050, Burlington, ON L7R 4A6 (Canada); Lair, Stéphane, E-mail: stephane.lair@umontreal.ca [Centre québécois sur la santé des animaux sauvages, Université de Montréal, C.P. 5000, St-Hyacinthe, QC J2S 7C6 (Canada); and others

    2014-11-01

    The development of integrated ecotoxicological approaches is of great interest in the investigation of global concerns such as impacts of municipal wastewater effluents on aquatic ecosystems. The objective of this study was to investigate the effects of a major wastewater municipal effluent on fish using a multi-level biological approach, from gene transcription and enzyme activities to histological changes. Yellow perch (Perca flavescens) were selected based on their wide distribution, their commercial and recreational importance, and the availability of a customized microarray. Yellow perch were sampled upstream of a major municipal wastewater treatment plant (WWTP) and 4 km and 10 km downstream from its point of discharge in the St. Lawrence River (Quebec, Canada). Concentrations of perfluoroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and metals/trace elements in whole body homogenates were comparable to those from other industrialized regions of the world. Genomic results indicated that the transcription level of 177 genes was significantly different (p < 0.024) between exposed and non-exposed fish. Among these genes, 38 were found to be differentially transcribed at both downstream sites. Impacted genes were associated with biological processes and molecular functions such as immunity, detoxification, lipid metabolism/energy homeostasis (e.g., peroxisome proliferation), and retinol metabolism suggesting impact of WWTP on these systems. Moreover, antioxidant enzyme activities were more elevated in perch collected at the 4 km site. Biomarkers of lipid metabolism, biosynthetic activity, and aerobic capacities were significantly lower (p < 0.05) in fish residing near the outfall of the effluent. Histological examination of the liver indicated no differences between sites. Correlations between PFAS, PBDE, and metal/trace element tissue concentrations and markers of peroxisomal proliferation, oxidative stress, and retinoid metabolism were found

  12. DNA barcode for genetic traceability of Nile Perch and Nile Tilapia

    International Nuclear Information System (INIS)

    Avossa, Valeria

    2017-01-01

    For this study, mitochondrial DNA was extracted from 55 fish samples (26 Nile Perch Samples and 29 Nile Tilapia Samples collected from 3 different Ugandan regions of Lake Victoria. In order to optimize the PCR method, we also extracted DNA from two other different fish samples: one from Italy and one from a Viennese market. The COI gene was amplified using universal primers (COI2, COI3, cocktails of 8 and 4 primers respectively). After the amplification step, the amplicons were analysed using gel electrophoresis , in order to establish that the set primers worked well in the samples. The positive results of an agarose gel electrophoresis analysis with the PCR amplicons (amplicons length ~700pb) are shown.

  13. Molecular evidence for association of chlamydiales bacteria with epitheliocystis in leafy seadragon (Phycodurus eques), silver perch (Bidyanus bidyanus), and barramundi (Lates calcarifer).

    NARCIS (Netherlands)

    Meijer, Adam; Roholl, Paul J M; Ossewaarde, Jacobus M; Jones, Brian; Nowak, Barbara F

    2006-01-01

    Epitheliocystis in leafy seadragon (Phycodurus eques), silver perch (Bidyanus bidyanus), and barramundi (Lates calcarifer), previously associated with chlamydial bacterial infection using ultrastructural analysis, was further investigated by using molecular and immunocytochemical methods.

  14. Factors influencing knowledge and practice of exclusive ...

    African Journals Online (AJOL)

    Factors influencing knowledge and practice of exclusive breastfeeding in Nyando ... The overall objective of this study was to determine factors influencing the ... EBF and its benefits), pre lacteal feeds and exclusive breastfeeding consistency.

  15. An update of hydrologic conditions and distribution of selected constituents in water, Snake River Plain aquifer and perched groundwater zones, Idaho National Laboratory, Idaho, emphasis 2006-08

    Science.gov (United States)

    Davis, Linda C.

    2010-01-01

    Since 1952, radiochemical and chemical wastewater discharged to infiltration ponds (also called percolation ponds), evaporation ponds, and disposal wells at the Idaho National Laboratory (INL) has affected water quality in the eastern Snake River Plain aquifer and perched groundwater zones underlying the INL. The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, maintains groundwater monitoring networks at the INL to determine hydrologic trends, and to delineate the movement of radiochemical and chemical wastes in the aquifer and in perched groundwater zones. This report presents an analysis of water-level and water-quality data collected from aquifer and perched groundwater wells in the USGS groundwater monitoring networks during 2006-08. Water in the Snake River Plain aquifer primarily moves through fractures and interflow zones in basalt, generally flows southwestward, and eventually discharges at springs along the Snake River. The aquifer primarily is recharged from infiltration of irrigation water, infiltration of streamflow, groundwater inflow from adjoining mountain drainage basins, and infiltration of precipitation. From March-May 2005 to March-May 2008, water levels in wells generally remained constant or rose slightly in the southwestern corner of the INL. Water levels declined in the central and northern parts of the INL. The declines ranged from about 1 to 3 feet in the central part of the INL, to as much as 9 feet in the northern part of the INL. Water levels in perched groundwater wells around the Advanced Test Reactor Complex (ATRC) also declined. Detectable concentrations of radiochemical constituents in water samples from wells in the Snake River Plain aquifer at the INL generally decreased or remained constant during 2006-08. Decreases in concentrations were attributed to decreased rates of radioactive-waste disposal, radioactive decay, changes in waste-disposal methods, and dilution from recharge and underflow. In April

  16. An Update of Hydrologic Conditions and Distribution of Selected Constituents in Water, Snake River Plain Aquifer and Perched-Water Zones, Idaho National Laboratory, Idaho, Emphasis 2002-05

    Science.gov (United States)

    Davis, Linda C.

    2008-01-01

    Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds, evaporation ponds, and disposal wells at the Idaho National Laboratory (INL) has affected water quality in the Snake River Plain aquifer and perched-water zones underlying the INL. The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, maintains ground-water monitoring networks at the INL to determine hydrologic trends, and to delineate the movement of radiochemical and chemical wastes in the aquifer and in perched-water zones. This report presents an analysis of water-level and water-quality data collected from aquifer and perched-water wells in the USGS ground-water monitoring networks during 2002-05. Water in the Snake River Plain aquifer primarily moves through fractures and interflow zones in basalt, generally flows southwestward, and eventually discharges at springs along the Snake River. The aquifer is recharged primarily from infiltration of irrigation water, infiltration of streamflow, ground-water inflow from adjoining mountain drainage basins, and infiltration of precipitation. From March-May 2001 to March-May 2005, water levels in wells declined throughout the INL area. The declines ranged from about 3 to 8 feet in the southwestern part of the INL, about 10 to 15 feet in the west central part of the INL, and about 6 to 11 feet in the northern part of the INL. Water levels in perched water wells declined also, with the water level dropping below the bottom of the pump in many wells during 2002-05. For radionuclides, concentrations that equal 3s, wheres s is the sample standard deviation, represent a measurement at the minimum detectable concentration, or 'reporting level'. Detectable concentrations of radiochemical constituents in water samples from wells in the Snake River Plain aquifer at the INL generally decreased or remained constant during 2002-05. Decreases in concentrations were attributed to decreased rates of radioactive-waste disposal

  17. Impairment of metabolic capacities in copper and cadmium contaminated wild yellow perch (Perca flavescens)

    International Nuclear Information System (INIS)

    Couture, Patrice; Rajender Kumar, Puja

    2003-01-01

    This study examined variations in resting oxygen consumption rate (ROCR), post-exercise oxygen consumption rate, relative scope for activity (RSA), liver and muscle aerobic and anaerobic capacities (using citrate synthase (CS) and lactate dehydrogenase, respectively, as indicators), and tissue biosynthetic capacities (using nucleoside diphosphate kinase (NDPK) as an indicator), in wild yellow perch from four lakes varying in copper (Cu) and cadmium (Cd) contamination. Liver Cu and Cd concentrations largely reflected environmental contamination and were positively correlated with liver protein concentrations and NDPK activities. Our results suggest that metal contamination leads to an upregulation of liver protein metabolism, presumably at least in part for the purpose of metal detoxification. In contrast, muscle NDPK activities decreased with increasing liver Cd concentrations and NDPK activities. There was a 25% decrease in ROCR for a doubling of liver Cu concentrations and a 42% decrease in RSA for a doubling of liver Cd concentrations in the range studied. Cu contamination was also associated with lower muscle CS activities. Our results support previous findings of impaired aerobic capacities in the muscle of metal-contaminated fish, and demonstrate that this impairment is also reflected in aerobic capacities of whole fish. The evidence presented suggests that mitochondria may be primary targets for inhibition by Cu, and that Cd may reduce gill respiratory capacity. Muscle aerobic and anaerobic capacities were inversely related. This work indicates that metal exposure of wild yellow perch leads to a wide range of disturbances in metabolic capacities

  18. Match or mismatch: the influence of phenology on size-dependent life history and divergence in population structure

    Science.gov (United States)

    Borcherding, Jost; Beeck, Peter; DeAngelis, Donald L.; Scharf, Werner R.

    2010-01-01

    Summary 1. In gape-limited predators, body size asymmetries determine the outcome of predator-prey interactions. Due to ontogenetic changes in body size, the intensity of intra- and interspecific interactions may change rapidly between the match situation of a predator-prey system and the mismatch situation in which competition, including competition with the prey, dominates. 2. Based on a physiologically structured population model using the European perch (Perca fluviatilis), analysis was performed on how prey density (bream, Abramis brama), initial size differences in the young-of-the-year (YOY) age cohort of the predator, and phenology (time-gap in hatching of predator and prey) influence the size structure of the predator cohort. 3. In relation to the seasonality of reproduction, the match situation of the predator-prey system occurred when perch hatched earlier than bream and when no gape-size limitations existed, leading to decreased size divergence in the predator age cohort. Decreased size divergence was also found when bream hatched much earlier than perch, preventing perch predation on bream occurring, which, in turn, increased the competitive interaction of the perch with bream for the common prey, zooplankton; i.e. the mismatch situation in which also the mean size of the age cohort of the predator decreased. 4. In between the total match and the mismatch, however, only the largest individuals of the perch age cohort were able to prey on the bream, while smaller conspecifics got trapped in competition with each other and with bream for zooplankton, leading to enlarged differences in growth that increased size divergence. 5. The modelling results were combined with 7 years of field data in a lake, where large differences in the length-frequency distribution of YOY perch were observed after their first summer. These field data corroborate that phenology and prey density per predator are important mechanisms in determining size differences within the YOY

  19. Factors that influencing veterinary drug’s metabolisation

    Directory of Open Access Journals (Sweden)

    Cristina, Romeo T.

    2007-12-01

    Full Text Available The paper wants to make a recall for the vet practitioners, of the main veterinary drug's metabolism rate influencing factors. Among the most important physiological factors (pharmacokinetics, sanguine flow and urinary ones, plasmatic proteins binding, enzymatic induction and inhibition are essential. Between the animal’s bounded factors more important are: species, individuality, age, sex, pregnancy, alimentation, genetic factors, and health status and from exogenous factors, daily rhythm, influences of chemical compounds and of the stress are presented.

  20. Factors influencing customer satisfaction with reference and ...

    African Journals Online (AJOL)

    This paper examines factors influencing customer satisfaction with reference and information services in an academic environment. The paper identifies types of reference services in libraries, factors influencing customer satisfaction and dissatisfaction with reference and information services and suggested the way forward ...

  1. Factors Influencing Endometrial Thickness in Postmenopausal Women

    African Journals Online (AJOL)

    Background: Cut‑off values for endometrial thickness (ET) in asymptomatic postmenopausal woman have been standardized. However, there are no comprehensive studies to document how various factors can influence the ET after the age of menopause. Aim: To study the various factors influencing the ET in ...

  2. Factors Influencing Livelihood Diversification among Rural Farmers ...

    African Journals Online (AJOL)

    This research study was set out to analyze factors influencing rural farmer's engagement in livelihood diversification in the study area. The specific objectives were; to identify the different levels of farmers' engagement in livelihood diversification, determine the socio-demographic factors or forces that influence farmers' ...

  3. Microbiological performance of Hazard Analysis Critical Control Point (HACCP)-based food safety management systems: A case of Nile perch processing company

    NARCIS (Netherlands)

    Kussaga, J.B.; Luning, P.A.; Tiisekwa, B.P.M.; Jacxsens, L.

    2017-01-01

    This study aimed at giving insight into microbiological safety output of a Hazard Analysis Critical Control Point (HACCP)-based Food Safety Management System (FSMS) of a Nile perch exporting company by using a combined assessment, This study aimed at giving insight into microbiological safety output

  4. Factors influencing choice of oral hygiene products by dental ...

    African Journals Online (AJOL)

    Background: Several factors, such as cost, branding, packaging and family influence, had been implicated as influencing the choice of toothpastes and toothbrushes by individuals. Media advertisement is also considered a very strong factor influencing consumer's choice. Aim: To assess the extent to which some factors ...

  5. ENERGY EFFICIENCY. TRENDS AND INFLUENCE FACTORS

    Directory of Open Access Journals (Sweden)

    Zizi GOSCHIN

    2006-12-01

    Full Text Available Energy efficiency is correlated with many factors of influence: Gross National Income per capita, energy imports (% of energy use, renewable combustible and waste (% of total, energy use per capita, services as % of GDP and others. In this paper we are testing a model of piecewise linear regression with breakpoint in order to measure the influence of these factors on the variation of GDP per unit of energy use in Europe in the year 2003.

  6. Activity and food choice of piscivorous perch ( Perca fluviatilis ) in a eutrophic shallow lake: a radio-telemetry study

    DEFF Research Database (Denmark)

    Jacobsen, Lene; Berg, Søren; Broberg, M.

    2002-01-01

    in midsummer. The general lack of activity at night supports the idea that perch is a visually oriented forager. 4. There was no significant relationship between daytime activity during the year and temperature or day length, but nighttime activity was correlated with temperature. In contrast with previous......+ planktivorous fish in lakes and has potential implications for pelagic food web structure and lake management by biomanipulation...

  7. What factors influence mitigative capacity?

    International Nuclear Information System (INIS)

    Winkler, Harald; Baumert, Kevin; Blanchard, Odile; Burch, Sarah; Robinson, John

    2007-01-01

    This article builds on Yohe's seminal piece on mitigative capacity, which elaborates 'determinants' of mitigative capacity, also reflected in the IPCC's third assessment report. We propose a revised definition, where mitigative capacity is a country's ability to reduce anthropogenic greenhouse gas emissions or enhance natural sinks. By 'ability' we mean skills, competencies, fitness, and proficiencies that a country has attained which can contribute to GHG emissions mitigation. A conceptual framework is proposed, linking mitigative capacity to a country's sustainable development path, and grouping the factors influencing mitigative capacity into three main sets: economic factors, institutional ones, and technology. Both quantitative and qualitative analysis of factors is presented, showing how these factors vary across countries. We suggest that it is the interplay between the three economic factors-income, abatement cost and opportunity cost-that shape mitigative capacity. We find that income is an important economic factor influencing mitigative capacity, while abatement cost is important in turning mitigative capacity into actual mitigation. Technology is a critical mitigative capacity, including the ability to absorb existing climate-friendly technologies or to develop innovative ones. Institutional factors that promote mitigative capacity include the effectiveness of government regulation, clear market rules, a skilled work force and public awareness. We briefly investigate such as high abatement cost or lack of political willingness that prevent mitigative capacity from being translated into mitigation

  8. Evaluation of risk factors for severe pneumonia in children: the Pneumonia Etiology Research for Child Health study

    NARCIS (Netherlands)

    Wonodi, Chizoba B.; Deloria-Knoll, Maria; Feikin, Daniel R.; DeLuca, Andrea N.; Driscoll, Amanda J.; Moïsi, Jennifer C.; Johnson, Hope L.; Murdoch, David R.; O'Brien, Katherine L.; Levine, Orin S.; Scott, J. Anthony G.; Black, Robert E.; Bhutta, Zulfiqar A.; Campbell, Harry; Cherian, Thomas; Crook, Derrick W.; de Jong, Menno D.; Dowell, Scott F.; Graham, Stephen M.; Klugman, Keith P.; Lanata, Claudio F.; Madhi, Shabir A.; Martin, Paul; Nataro, James P.; Piazza, Franco M.; Qazi, Shamim A.; Zar, Heather J.; Baggett, Henry C.; Brooks, W. Abdullah; Chipeta, James; Ebruke, Bernard; Endtz, Hubert P.; Groome, Michelle; Hammitt, Laura L.; Howie, Stephen R. C.; Kotloff, Karen; Maloney, Susan A.; Moore, David; Otieno, Juliet; Seidenberg, Phil; Tapia, Milagritos; Thamthitiwat, Somsak; Thea, Donald M.; Zaman, Khaleque

    2012-01-01

    As a case-control study of etiology, the Pneumonia Etiology Research for Child Health (PERCH) project also provides an opportunity to assess the risk factors for severe pneumonia in hospitalized children at 7 sites. We identified relevant risk factors by literature review and iterative expert

  9. Perch, Perca fluviatilis show a directional preference for, but do not increase attacks toward, prey in response to water-borne cortisol

    Directory of Open Access Journals (Sweden)

    Lindsay J. Henderson

    2017-10-01

    Full Text Available In freshwater environments, chemosensory cues play an important role in predator-prey interactions. Prey use a variety of chemosensory cues to detect and avoid predators. However, whether predators use the chemical cues released by disturbed or stressed prey has received less attention. Here we tested the hypothesis that the disturbance cue cortisol, in conjunction with visual cues of prey, elevates predatory behavior. We presented predators (perch, Perca fluviatilis with three chemosensory choice tests and recorded their location, orientation, and aggressive behavior. We compared the responses of predators when provided with (i visual cues of prey only (two adjacent tanks containing sticklebacks; (ii visual and natural chemical cues of prey vs. visual cues only; and (iii visual cues of prey with cortisol vs. visual cues only. Perch spent a significantly higher proportion of time in proximity to prey, and orientated toward prey more, when presented with a cortisol stimulus plus visual cues, relative to presentations of visual and natural chemical cues of prey, or visual cues of prey only. There was a trend that perch directed a higher proportion of predatory behaviors (number of lunges toward sticklebacks when presented with a cortisol stimulus plus visual cues, relative to the other chemosensory conditions. But they did not show a significant increase in total predatory behavior in response to cortisol. Therefore, it is not clear whether water-borne cortisol, in conjunction with visual cues of prey, affects predatory behavior. Our results provide evidence that cortisol could be a source of public information about prey state and/or disturbance, but further work is required to confirm this.

  10. Temperature effects on aerobic scope and cardiac performance of European perch (Perca fluviatilis).

    Science.gov (United States)

    Jensen, Denise Lyager; Overgaard, Johannes; Wang, Tobias; Gesser, Hans; Malte, Hans

    2017-08-01

    Several recent studies have highlighted how impaired cardiac performance at high temperatures and in hypoxia may compromise the capacity for oxygen transport. Thus, at high temperatures impaired cardiac capacity is proposed to reduce oxygen transport to a degree that lowers aerobic scope and compromises thermal tolerance (the oxygen- and capacity-limited thermal tolerance (OCLTT) hypothesis). To investigate this hypothesis, we measured aerobic and cardiac performance of a eurythermal freshwater teleost, the European perch (Perca fluviatilis). Rates of oxygen consumption were measured during rest and activity at temperatures between 5°C and 27°C, and we evaluated cardiac function by in vivo measurements of heart rate and in vitro studies to determine contractility of myocardial strips. Aerobic scope increased progressively from 5°C to 21°C, after which it levelled off. Heart rate showed a similar response. We found little difference between resting and active heart rate at high temperature suggesting that increased cardiac scope during activity is primarily related to changes in stroke volume. To examine the effects of temperature on cardiac capacity, we measured isometric force development in electrically paced myocardial preparations during different combinations of temperature, pacing frequency, oxygenation and adrenergic stimulation. The force-frequency product increased markedly upon adrenergic stimulation at 21 and 27°C (with higher effects at 21°C) and the cardiac preparations were highly sensitive to hypoxia. These findings suggest that at (critically) high temperatures, cardiac output may diminish due to a decreased effect of adrenergic stimulation and that this effect may be further exacerbated if the heart becomes hypoxic. Hence cardiac limitations may contribute to the inability to increase aerobic scope at high temperatures in the European perch (Perca fluviatilis). Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. The cephalic lateral line system of temperate perches (Perciformes: Percichthyidae from Argentinean Patagonia

    Directory of Open Access Journals (Sweden)

    Rocío M. Vega

    Full Text Available ABSTRACT The species of Percichthys (Percichthyidae are endemic to southern South America. Some authors have pointed out that the genus includes four valid species, based on the morphology of the head, jaws, and fins. A phylogenetic analysis published by other authors suggests that three of them are morphotypes belonging to the same species, Percichthys trucha (Valenciennes, 1833. The aim of this study is to describe for the first time the morphology of the cephalic seismosensory system of Patagonian perches, and how these characters vary in the three morphotypes, in order to provide morphological elements to analyze the taxonomy of these fish species. Comparisons of the cephalic seismosensory system between juveniles and adults were also conducted. Juvenile and adult specimens were collected in the northwestern Argentinean Patagonia. Specimens were bleached in 5% H2O2 and the canal systems of their cephalic lateral line were filled with hematoxylin. Specimens were deposited in the Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Argentina. The cephalic lateral line of the studied specimens is a widened type of canal systems, is not connected to the trunk lateral line, and consists of preopercular-mandibular canal, infraorbital canal, supraorbital canal, temporal canal, supratemporal canal, and a supraorbital commisure. The number of pores increases during the ontogeny, while their diameters decrease. The number, position and size of infraorbital canal pores showed significant differences among morphotypes and juveniles. The interpopulation variation regarding the number, position, and size of pores seems to signal an ongoing process of speciation, which is the result adaptations to different environmental conditions. Our study contributes to the knowledge of the morphology of percichthids and describes for the first time the seismosensory system of temperate perches.

  12. Factors Influencing Colorectal Cancer Screening Participation

    Directory of Open Access Journals (Sweden)

    Antonio Z. Gimeno García

    2012-01-01

    Full Text Available Colorectal cancer (CRC is a major health problem worldwide. Although population-based CRC screening is strongly recommended in average-risk population, compliance rates are still far from the desirable rates. High levels of screening uptake are necessary for the success of any screening program. Therefore, the investigation of factors influencing participation is crucial prior to design and launches a population-based organized screening campaign. Several studies have identified screening behaviour factors related to potential participants, providers, or health care system. These influencing factors can also be classified in non-modifiable (i.e., demographic factors, education, health insurance, or income and modifiable factors (i.e., knowledge about CRC and screening, patient and provider attitudes or structural barriers for screening. Modifiable determinants are of great interest as they are plausible targets for interventions. Interventions at different levels (patient, providers or health care system have been tested across the studies with different results. This paper analyzes factors related to CRC screening behaviour and potential interventions designed to improve screening uptake.

  13. The Influence of Keel Bone Damage on Welfare of Laying Hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Casey-Trott, Teresa M.; Herskin, Mette S.

    2018-01-01

    This article reviews current knowledge about welfare implications of keel bone damage in laying hens. As an initial part, we shortly describe the different conditions and present major risk factors as well as findings on the prevalence of the conditions. Keel bone damage is found in all types...... of commercial production, however with varying prevalence across systems, countries, and age of the hens. In general, the understanding of animal welfare is influenced by value-based ideas about what is important or desirable for animals to have a good life. This review covers different types of welfare...... indicators, including measures of affective states, basic health, and functioning as well as natural living of the birds, thereby including the typical public welfare concerns. Laying hens with keel bone fractures show marked behavioral differences in highly motivated behavior, such as perching, nest use...

  14. Hawk eyes II: diurnal raptors differ in head movement strategies when scanning from perches.

    Science.gov (United States)

    O'Rourke, Colleen T; Pitlik, Todd; Hoover, Melissa; Fernández-Juricic, Esteban

    2010-09-22

    Relatively little is known about the degree of inter-specific variability in visual scanning strategies in species with laterally placed eyes (e.g., birds). This is relevant because many species detect prey while perching; therefore, head movement behavior may be an indicator of prey detection rate, a central parameter in foraging models. We studied head movement strategies in three diurnal raptors belonging to the Accipitridae and Falconidae families. We used behavioral recording of individuals under field and captive conditions to calculate the rate of two types of head movements and the interval between consecutive head movements. Cooper's Hawks had the highest rate of regular head movements, which can facilitate tracking prey items in the visually cluttered environment they inhabit (e.g., forested habitats). On the other hand, Red-tailed Hawks showed long intervals between consecutive head movements, which is consistent with prey searching in less visually obstructed environments (e.g., open habitats) and with detecting prey movement from a distance with their central foveae. Finally, American Kestrels have the highest rates of translational head movements (vertical or frontal displacements of the head keeping the bill in the same direction), which have been associated with depth perception through motion parallax. Higher translational head movement rates may be a strategy to compensate for the reduced degree of eye movement of this species. Cooper's Hawks, Red-tailed Hawks, and American Kestrels use both regular and translational head movements, but to different extents. We conclude that these diurnal raptors have species-specific strategies to gather visual information while perching. These strategies may optimize prey search and detection with different visual systems in habitat types with different degrees of visual obstruction.

  15. Effects of dietary n-3 and n-6 fatty acids levels on egg and larval quality of Eurasian perch

    DEFF Research Database (Denmark)

    Henrotte, E.; Overton, Julia Lynne; Kestemont, P.

    2008-01-01

    Three groups of 40 perch breeders were reared in order to study the effects of 3 different levels of dietary n-3 and n-6 fatty acids on egg quality. Two experimental diets, R1 and R2 (n-3/n-6 = 0.13 and 35.54, respectively), were compared to one commercial food, R3 (n-3/n-6 = 3.48.). Spawning and...

  16. An Investigation into factors influencing the choice of business ...

    African Journals Online (AJOL)

    There was significant difference between male and female career influencing factors. There was no significant difference regarding the influence exercised by parent in the students' choice of Business Education. There is significant difference between male and female in the influence exerted by external factors in their ...

  17. Urban water consumption and its influencing factors in China

    NARCIS (Netherlands)

    Fan, Liangxin; Gai, Lingtong; Tong, Yan; Li, Ruihua

    2017-01-01

    Factors that affect water consumption should be identified to develop effective public policies. However, factors influencing domestic water consumption in cities in China, particularly on a national scale, are unclear. In this study, urban water consumption and its influencing factors in 286

  18. Factors Influencing Pregnancy Desires among HIV Positive Women ...

    African Journals Online (AJOL)

    Factors Influencing Pregnancy Desires among HIV Positive Women in Sibande District in Mpumalanga, South Africa. ... Gender and Behaviour ... The objective of the study is to present findings on factors influencing pregnancy desires amongst HIV positive women that have participated in Prevention of Mother to child ...

  19. Social Factors Influencing Child Health in Ghana.

    Directory of Open Access Journals (Sweden)

    Emmanuel Quansah

    Full Text Available Social factors have profound effects on health. Children are especially vulnerable to social influences, particularly in their early years. Adverse social exposures in childhood can lead to chronic disorders later in life. Here, we sought to identify and evaluate the impact of social factors on child health in Ghana. As Ghana is unlikely to achieve the Millennium Development Goals' target of reducing child mortality by two-thirds between 1990 and 2015, we deemed it necessary to identify social determinants that might have contributed to the non-realisation of this goal.ScienceDirect, PubMed, MEDLINE via EBSCO and Google Scholar were searched for published articles reporting on the influence of social factors on child health in Ghana. After screening the 98 articles identified, 34 of them that met our inclusion criteria were selected for qualitative review.Major social factors influencing child health in the country include maternal education, rural-urban disparities (place of residence, family income (wealth/poverty and high dependency (multiparousity. These factors are associated with child mortality, nutritional status of children, completion of immunisation programmes, health-seeking behaviour and hygiene practices.Several social factors influence child health outcomes in Ghana. Developing more effective responses to these social determinants would require sustainable efforts from all stakeholders including the Government, healthcare providers and families. We recommend the development of interventions that would support families through direct social support initiatives aimed at alleviating poverty and inequality, and indirect approaches targeted at eliminating the dependence of poor health outcomes on social factors. Importantly, the expansion of quality free education interventions to improve would-be-mother's health knowledge is emphasised.

  20. Modeling Factors with Influence on Sustainable University Management

    Directory of Open Access Journals (Sweden)

    Oana Dumitrascu

    2015-01-01

    Full Text Available The main objective of this paper is to present the factors with influence on the sustainable university management and the relationships between them. In the scientific approach we begin from a graphical model, according to which the extracurricular activities together with internal environmental factors influence students’ involvement in such activities, the university attractiveness, their academic performance and their integration into the socially-economic and natural environment (components related with sustainable development. The model emphasizes that individual performances, related to students’ participation in extracurricular activities, have a positive influence on the sustainability of university management. The results of the study have shown that the university sustainability may be influenced by a number of factors, such as students’ performance, students’ involvement in extracurricular activities or university’s attractiveness and can in turn influence implicitly also the sustainability of university management. The originality of the paper consists in the relationships study using the modeling method in general and informatics tools of modeling in particular, as well as through graphical visualization of some influences, on the sustainability university management.

  1. FACTORS INFLUENCING SECOND LANGUAGE ACQUISITION

    Directory of Open Access Journals (Sweden)

    Siti Khasinah

    2014-05-01

    Full Text Available Motivation, attitude, age, intelligence, aptitude, cognitive style, and personality are considered as factors that greatly influence someone in the process of his or her second language acquisition. Experts state that those factors give a more dominant contribution in SLA to learners variedly, depend on who the learners are, their age, how they behave toward the language, their cognitive ability, and also the way they learn.

  2. Influence of organizational factors on safety

    International Nuclear Information System (INIS)

    Haber, S.B.; Metlay, D.S.; Crouch, D.A.

    1990-01-01

    There is a need for a better understanding of exactly how organizational management factors at a nuclear power plant (NPP) affect plant safety performance, either directly or indirectly, and how these factors might be observed, measured, and evaluated. The purpose of this research project is to respond to that need by developing a general methodology for characterizing these organizational and management factors, systematically collecting information on their status and integrating that information into various types of evaluative activities. Research to date has included the development of the Nuclear Organization and Management Analysis Concept (NOMAC) of a NPP, the identification of key organizational and management factors, and the identification of the methods for systematically measuring and analyzing the influence of these factors on performance. Most recently, two field studies, one at a fossil fuel plant and the other at a NPP, were conducted using the developed methodology. Results are presented from both studies highlighting the acceptability, practicality, and usefulness of the methods used to assess the influence of various organizational and management factors including culture, communication, decision-making, standardization, and oversight. 6 refs., 3 figs., 1 tab

  3. INFLUENCE FACTORS FOR LEASING MARKET CONTRACTS

    Directory of Open Access Journals (Sweden)

    Oana BĂRBULESCU

    2016-11-01

    Full Text Available This paper aims to investigate the relationship between leasing contracts and some factors that influence the value of these contracts. In order to do this, we have decided on some quantitative marketing research by appealing to statistics for accomplishing the objectives that we have set: to find a correlation between the turnover percentage assigned to leasing expenses and several influence factors. This study indicated that the more contracts are signed by a firm, the more likely is to assign a bigger fraction of the income to each new leasing contract. The study confirmed that bigger companies are relying more on leasing as a way of financing than small companies. This study also discovered that companies with more employees are using larger contracts in order to sustain their activity. The findings are expected to contribute to adjusting the offers by the leasing companies, taking into consideration these factors and to using these factors in order to better predict the market evolution.

  4. Factors that negatively influence consumption of traditionally ...

    African Journals Online (AJOL)

    Factors that negatively influence consumption of traditionally fermented milk ... in various countries of sub-Saharan Africa and a number of health benefits to human ... influence consumption of Mursik, a traditionally fermented milk product from ...

  5. Formation of perched lava ponds on basaltic volcanoes: Interaction between cooling rate and flow geometry allows estimation of lava effusion rates

    Science.gov (United States)

    Wilson, L.; Parfitt, E. A.

    1993-01-01

    Perched lava ponds are infrequent but distinctive topographic features formed during some basaltic eruptions. Two such ponds, each approximately 150 m in diameter, formed during the 1968 eruption at Napau Crater and the 1974 eruption of Mauna Ulu, both on Kilauea Volcano, Hawaii. Each one formed where a channelized, high volume flux lava flow encountered a sharp reduction of slope: the flow spread out radially and stalled, forming a well-defined terminal levee enclosing a nearly circular lava pond. We describe a model of how cooling limits the motion of lava spreading radially into a pond and compare this with the case of a channelized flow. The difference in geometry has a major effect, such that the size of a pond is a good indicator of the volume flux of the lava forming it. Lateral spreading on distal shallow slopes is a major factor limiting the lengths of lava flows.

  6. Factors Influencing Organization Adoption Decision On Cloud Computing

    OpenAIRE

    Ailar Rahimli

    2013-01-01

    Cloud computing is a developing field, using by organization that require to computing resource to provide the organizational computing needs. The goal of this research is evaluate the factors that influence on organization decision to adopt the cloud computing in Malaysia. Factors that relate to cloud computing adoption that include : need for cloud computing, cost effectiveness, security effectiveness of cloud computing and reliability. This paper evaluated the factors that influence on ado...

  7. PERCH in Perspective: What Can It Teach Us About Pneumonia Etiology in Children?

    Science.gov (United States)

    Klugman, Keith P; Rodgers, Gail L

    2017-06-15

    The pneumonia team at the Bill & Melinda Gates Foundation congratulates the Pneumonia Etiology Research for Child Health (PERCH) study on delivering on their grant to collect high-quality data from thousands of children with World Health Organization-defined severe and very severe pneumonia and from controls in 9 diverse sites in 7 low- and middle-income countries. This supplement sets the foundation to understanding this complex study by providing an in-depth description of the study methodology, including discussion of key aspects such as antibiotic pretreatment, chest radiograph interpretation, utility of induced sputum in children, measurement of pathogen density, and use of C-reactive protein, and how these affect pneumonia etiology. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  8. A Comparison of Factors that Influence the Lyophilization Process

    OpenAIRE

    Mnerie, Dumitru; Anghel, Gabriela Victoria; Mnerie, Alin Vasile; Cheveresan, Constantin

    2007-01-01

    The lyophilization (or freeze drying) process for agro-foods products depends on a series of technological factors that are in an inter-dependence with the process performance. This paper presents an expert method and its application. This method characterizes the influence factors of the lyophilization process, after the importance level of some factors in correlation with other factors, is defined. Only the most important factors were considered; influence considerations were made in relati...

  9. Quantitative analysis of seed rain under natural and artificial perches in the Araucaria Forest Análise quantitativa da chuva de sementes sob poleiros naturais e artificiais em Floresta Ombrófila Mista

    Directory of Open Access Journals (Sweden)

    Sandra Bos Mikich

    2010-06-01

    Full Text Available The objective of this study was to compare the efficiency in terms of number of seeds deposited under natural and artificial bird-perches set in degraded areas of Araucaria Forest. Six experimental units were used, each containing seed traps set under natural perches (NP, artificial perches (AP and under open sky (OS. After 12 months of weekly sampling 26880 zoochoric seeds were collected under AP, 5729 under NP, and only seven under OS. Thus, the presence of perches increases dramatically seed deposition and NP are more or as efficient as AP when the effect of deposition area is taken into account.O objetivo deste estudo foi comparar a eficiência de poleiros naturais e artificiais na deposição de
    sementes em áreas degradadas da Floresta com Araucária. Seis unidades experimentais foram utilizadas, cada qual constituída por coletores de sementes instalados sob poleiros naturais (PN, artificiais (PA e a céu aberto (CA. Após 12 meses de coletas semanais, foram recolhidas 26.880 sementes zoocóricas sob os PA, 5.729 sob os PN e 7 nos CA. Portanto, a presença de poleiros incrementa significativamente a chuva de sementes e os PN são tão ou mais eficientes que os PA quando o efeito da área de deposição é levado em consideração.

  10. Factors influencing e-commerce development in Serbia

    OpenAIRE

    Kalinić, Zoran; Ranković, Vladimir; Kalinić, Ljubina

    2016-01-01

    In this paper, an overview of current state of e-commerce development in Serbia is presented. Also, some important factors influencing e-commerce diffusion are discussed. The factors are divided into four groups: technical factors, which cover e- commerce telecommunication and logistics infrastructure; legal factors, i.e. necessary laws and regulations on e-commerce; economic factors, and psychological factors and local culture. The study showed very strong correlation between broadband inter...

  11. Factors that influence beverage choices at meal times

    DEFF Research Database (Denmark)

    Mueller Loose, Simone; Jaeger, S. R.

    2012-01-01

    Beverages are consumed at almost every meal occasion, but knowledge about the factors that influence beverage choice is less than for food choice. The aim of this research was to characterize and quantify factors that influence beverage choices at meal times. Insights into what beverages are chosen...... consumers. Participants (n=164) described 8356 meal occasions in terms of foods and beverages consumed, and the contextual characteristics of the occasion. Beverage choice was explored with random-parameter logit regressions to reveal influences linked to food items eaten, context factors and person factors....... Thereby this study contributed to the food choice kaleidoscope research approach by expressing the degree of context dependency in form of odds ratios and according significance levels. The exploration of co-occurrence of beverages with food items suggests that beverage-meal item combinations can be meal...

  12. Intrinsic and extrinsic factors influencing large African herbivore movements

    NARCIS (Netherlands)

    Venter, J.A.; Prins, H.H.T.; Mashanova, A.; Boer, de W.F.; Slotow, R.

    2015-01-01

    Understanding environmental as well as anthropogenic factors that influence large herbivore ecological patterns and processes should underpin their conservation and management. We assessed the influence of intrinsic, extrinsic environmental and extrinsic anthropogenic factors on movement behaviour

  13. Variation and accumulation patterns of poly- and perfluoroalkyl substances (PFAS) in European perch (Perca fluviatilis) across a gradient of pristine Swedish lakes.

    Science.gov (United States)

    Åkerblom, Staffan; Negm, Nesrin; Wu, Pianpian; Bishop, Kevin; Ahrens, Lutz

    2017-12-01

    This study assessed variations in the concentrations of poly- and perfluoroalkyl substances (PFAS) in European perch (Perca fluviatilis) in Swedish lakes and the extent to which fish size, age and indicators of fish trophic ecology (δ 15 N and δ 13 C) correlate with the sum of individual PFAS concentrations (ΣPFAS). Fish muscle tissue samples (n=80) were taken from six lakes across Sweden and analysed using solid-liquid extraction followed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). PFAS levels in the lakes were affected by atmospheric deposition in relatively pristine areas with no direct point source of PFAS in the catchment. PFTeDA, PFUnDA, PFTriDA, PFDoDA, PFDA, PFOS and 6:2 FTSA were detected with a frequency between 68% and 99% and were included in the statistical evaluation. ΣPFAS differed between lakes (ANOVA: F=50.6, pPFAS, with a maximum ΣPFAS of 3.4ng g -1 wet weight (ww) (mean±SD: 0.99±0.63ng g -1 ww), while the lowest levels were found in lake Björntjärn (0.31±0.08ng g -1 ww) in northern Sweden (63°54'N, 18°51'E). PFOS was most abundant in perch from south-western Sweden, while other long-chain perfluorocarbons (>10 carbon atoms) were relatively more abundant in lakes in northern Sweden. Pearson correlation coefficients indicated that concentrations of PFAS in perch did not show any relation to fish size or age and were negatively correlated with trophic position of the fish (δ 15 N). It was also found that ΣPFAS were negatively correlated with both latitude and altitude. The PFAS data in this study represent national background concentrations in freshwater fish across Swedish lakes. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Factors influencing workplace health promotion intervention: a qualitative systematic review.

    Science.gov (United States)

    Rojatz, Daniela; Merchant, Almas; Nitsch, Martina

    2017-10-01

    Although workplace health promotion (WHP) has evolved over the last 40 years, systematically collected knowledge on factors influencing the functioning of WHP is scarce. Therefore, a qualitative systematic literature review was carried out to systematically identify and synthesize factors influencing the phases of WHP interventions: needs assessment, planning, implementation and evaluation. Research evidence was identified by searching electronic databases (Scopus, PubMed, Social Sciences Citation Index, ASSIA, ERIC, IBBS and PsycINFO) from 1998 to 2013, as well as by cross-checking reference lists of included peer-reviewed articles. The inclusion criteria were: original empirical research, description of WHP, description of barriers to and/or facilitators of the planning, implementation and/or evaluation of WHP. Finally, 54 full texts were included. From these, influencing factors were extracted and summarized using thematic analysis. The majority of influencing factors referred to the implementation phase, few dealt with planning and/or evaluation and none with needs assessment. The influencing factors were condensed into topics with respect to factors at contextual level (e.g. economic crisis); factors at organizational level (e.g. management support); factors at intervention level (e.g. quality of intervention concept); factors at implementer level (e.g. resources); factors at participant level (e.g. commitment to intervention) and factors referring to methodological and data aspects (e.g. data-collection issues). Factors regarding contextual issues and organizational aspects were identified across three phases. Therefore, future research and practice should consider not only the influencing factors at different levels, but also at different phases of WHP interventions. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Factors influencing bone scan quality

    International Nuclear Information System (INIS)

    Adams, F.G.; Shirley, A.W.

    1983-01-01

    A reliable subjective method of assessing bone scan quality is described. A large number of variables which theoretically could influence scan quality were submitted to regression and factor analysis. Obesity, age, sex and abnormality of scan were found to be significant but weak variables. (orig.)

  16. Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. II: live weight, health measures and perching

    DEFF Research Database (Denmark)

    Steenfeldt, Sanna; Nielsen, Birte L.

    2015-01-01

    regulations on the keeping of organic laying hens. Hen live weight, mortality and foot health were not affected by the stocking densities used in the present study. Other variables (plumage condition, presence of breast redness and blisters, pecked tail feathers, and perch use) were indirectly affected...

  17. Factors influencing consumer behaviour in market vegetables in Yemen

    Directory of Open Access Journals (Sweden)

    Tarish H. Al-Gahaifi

    2011-01-01

    Full Text Available The purpose of the research is to understand factors influencing consumer behaviour when buying vegetables in Republic of Yemen. Data collection was done by structured questionnaire administered through schools, universities, government offices, and markets from 13 provinces in 5 governorates. Random convenience sampling technique was used. Total sample comprised of 463 completed questionnaires which were used for analysis. The respondents were classified into five categories on the base of their monthly income, age, education, gender, and type of settlement. Authors present the factors that can influence significantly this behaviour, e.g. price, quality, the location of seller, habit, personal relationship between consumer and seller, occasions, discount, sorting, word-mouth, time of purchase, the way of products display, and recommendation of friends and families. From the obtained results, it is obvious that there was high influence on the behaviour of Yemeni consumer when buying vegetables for factors price, occasions, discontent, and time of purchase, while factors habit, display, sorting, and the location of seller suggests medium influence, and the influence was low for word-mouth.

  18. What factors influence British medical students' career intentions?

    Science.gov (United States)

    Ibrahim, Michael; Fanshawe, Angela; Patel, Vanash; Goswami, Karan; Chilvers, Geoffrey; Ting, Michelle; Pilavakis, Yiannis; Rao, Christopher; Athanasiou, Thanos

    2014-12-01

    The aim of this study was to identify factors that influence career choice in UK medical students. Students at seven institutions were invited to rate how important various factors were on influencing their career choices and how interested they were in pursuing different specialties. The influence of interpersonal relationship networks on career choice was also evaluated. 641 responses were collected. 44% (283) were male, 16% (105) were graduates and 41% (263) were final-year students. For Dermatology (p = 0.009), Paediatrics (p = 0.000), Radiology (p = 0.000), Emergency Medicine (p = 0.018) and Cardiothoracic Surgery (p = 0.000), there was a clear correlation between completing a clinical attachment and an interest in pursuing the specialty. Perceived characteristics of the speciality, individually and in clusters were considered important by specific subgroups of students, such as those interested in surgery. These students considered prestige (p = 0.0003), role models (p = 0.014), financial rewards after training (p = 0.0196) and technical challenge (p = 0.0011) as important factors. Demographics such as sex and age played a significant role in career choice. Interpersonal relationship networks do not have a significant influence on career intentions. This study shows that the career intentions of British medical students are influenced by their undergraduate experience and by the weight they place on different specialty-related factors.

  19. Factors negatively influencing knowledge sharing in software development

    Directory of Open Access Journals (Sweden)

    Lucas T. Khoza

    2017-07-01

    Objective: This study seeks to identify factors that negatively influence knowledge sharing in software development in the developing country context. Method: Expert sampling as a subcategory of purposive sampling was employed to extract information, views and opinions from experts in the field of information and communication technology, more specifically from those who are involved in software development projects. Four Johannesburg-based software developing organisations listed on the Johannesburg Stock Exchange (JSE, South Africa, participated in this research study. Quantitative data were collected using an online questionnaire with closed-ended questions. Results: Findings of this research reveal that job security, motivation, time constraints, physiological factors, communication, resistance to change and rewards are core factors negatively influencing knowledge sharing in software developing organisations. Conclusions: Improved understanding of factors negatively influencing knowledge sharing is expected to assist software developing organisations in closing the gap for software development projects failing to meet the triple constraint of time, cost and scope.

  20. Artificial perches as a nucleation technique for restoration of a riparian environment: characterization of the seed rain and of natural regeneration

    Directory of Open Access Journals (Sweden)

    Aline Luiza Tomazi

    2010-09-01

    Full Text Available Riparian habitats are important to the maintenance of ecological processes and environmental services. However, a significant portion of the riparian vegetation in the Brazilian Atlantic forest has been removed in response to increasing human pressure. Therefore, the application of restoration techniques in these habitats becomes essential. In this context, a nucleation model with 18 artificial perches was evaluated for the restoration of a degraded riparian area in Gaspar, Santa Catarina, Brazil, by the characterization of the seed rain and natural regeneration. In two years we collected 21,864 seeds of 51 morphospecies, and recorded 42 colonizing species. Zoochoric seeds belonging to 15 plant families comprised 17% of the seed rain and 19.05% of the spontaneously regenerating plant species. Asteraceae and Poaceae were the most represented families. The artificial perches performed the nucleating function through the increase of zoochoric seed rain. However, possibly due to different barriers that were not evaluated in this study, part of these seeds was not recruited. We recommend the application of this technique for the attraction of dispersers in degraded areas similar to the study site.

  1. Artificial perches as a nucleation technique for restoration of a riparian environment: characterization of the seed rain and of natural regeneration.

    Directory of Open Access Journals (Sweden)

    Aline Luiza Tomazi

    2010-01-01

    Full Text Available Riparian habitats are important to the maintenance of ecological processes and environmental services. However, a significant portion of the riparian vegetation in the Brazilian Atlantic forest has been removed in response to increasing human pressure. Therefore, the application of restoration techniques in these habitats becomes essential. In this context, a nucleation model with 18 artificial perches was evaluated for the restoration of a degraded riparian area in Gaspar, Santa Catarina, Brazil, by the characterization of the seed rain and natural regeneration. In two years we collected 21,864 seeds of 51 morphospecies, and recorded 42 colonizing species. Zoochoric seeds belonging to 15 plant families comprised 17% of the seed rain and 19.05% of the spontaneously regenerating plant species. Asteraceae and Poaceae were the most represented families. The artificial perches performed the nucleating function through the increase of zoochoric seed rain. However, possibly due to different barriers that were not evaluated in this study, part of these seeds was not recruited. We recommend the application of this technique for the attraction of dispersers in degraded areas similar to the study site.

  2. Summary of the results and interpretation of tritium and noble gas measurements on groundwater samples from the Perch Lake Basin Area

    International Nuclear Information System (INIS)

    Kotzer, T.G.

    1999-02-01

    Along the west-central margin of the Lower Perch Lake Basin, a limited number of groundwaters have been sampled from piezometers at depths of between 8 and 17 m and distances of between 100 and 900 m downgradient from their recharge location near Area A. Concentrations of tritium in these groundwaters varied between approximately 100 and 2800 TU. Measurements of dissolved gases in these groundwaters indicate concentrations of 4 He and neon approximating those in recently recharged groundwaters; however, the concentrations of 3 He are as much as 100 times higher, indicating the waters have accumulated tritiogenic 3 He. Using the 3 H/ 3 He dating technique, groundwater residence times on the order of 29 ± 8 years and groundwater velocities on the order of 0.1 m/day have been calculated for the flow system in the middle sand unit between Area A recharge and Perch Lake. These results, although based on a very small number of groundwater analyses, are comparable to earlier estimates of groundwater residence times and velocities obtained using Darcy calculations, borehole dilution experiments and tracer-test results from previous hydrogeologic studies in the area. (author)

  3. The Influence of psychological-sociological factors on self-employment

    OpenAIRE

    Remeikienė, Rita; Startienė, Gražina; Vasauskaitė, Jovita

    2011-01-01

    The article deals with the influence of psychological-sociological factors on a self-employed person, which is little explored in business literature. Analysis of scientific literature revealed that the psychological-sociological factors of self-employment can be divided into groups based on certain personal characteristics and individual psychological states, and the influence of psychological-sociological factors of self-employment is threefold: positive, negative, and unclear (both positiv...

  4. A survey on critical factors influencing organizational commitment

    Directory of Open Access Journals (Sweden)

    Hamidreza Kheirkhah

    2014-04-01

    Full Text Available Organizational commitment is an important issue and organization attitude has become an area of study among many researchers in the fields of organizational behavior. In fact, there are many studies on human resource management where the effects of organizational commitment on other issues have been investigated and the purpose of this research is to find critical factors influencing on organizational commitment. Based on an exploration of the literature review and interviews, the proposed study of this paper extracts 24 variables and using factor analysis, we select the most important factors, which are grouped in four categories. The implementation of our factor analysis has revealed Affective commitment, Continuous commitment, Moral commitment and Enduring commitment are the most important factors influencing organizational commitment.

  5. Hierarchical and coupling model of factors influencing vessel traffic flow.

    Science.gov (United States)

    Liu, Zhao; Liu, Jingxian; Li, Huanhuan; Li, Zongzhi; Tan, Zhirong; Liu, Ryan Wen; Liu, Yi

    2017-01-01

    Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system.

  6. [Factors influencing nurses' organizational citizenship behavior].

    Science.gov (United States)

    Park, Junhee; Yun, Eunkyung; Han, Sangsook

    2009-08-01

    This study was conducted to identify the factors that influence nurses' organizational citizenship behavior. A cross-sectional design was used, with a convenience sample of 547 nurses from four university hospitals in Seoul and Gyeonggi province. The data were collected through a questionnaire survey done from September 22 to October 10, 2008. The tools used for this study were scales on organizational citizenship behavior (14 items), self-leadership (14 items), empowerment (10 items), organizational commitment (7 items), job satisfaction (8 items) and transformational.transactional leadership (14 items). Cronbach's alpha and factor analysis were examined to test reliability and construct validity of the scale. The data collected were processed using SPSS Window 15.0 Program for actual numbers and percentages, differences in the dependent variable according to general characteristics, and means, standard deviations, correlation coefficients and multiple regression analysis. The factors influencing nurses' organizational citizenship behavior were identified as self-leadership(beta=.247), empowerment (beta=.233), job satisfaction (beta=.209), organizational commitment (beta=.158), and transactional leadership (beta=.142). Five factors explained 42.0% of nurses' organizational citizenship behavior. The results of this study can be used to develop further management strategies for enhancement of nurses' organizational citizenship behavior.

  7. Factors Influencing Title VII Bilingual Program Institutionalization.

    Science.gov (United States)

    Lewis, Gerald R.; And Others

    1985-01-01

    This study of the primary restraining and driving forces that influence Title VII bilingual education programs found the external environment, the local community, to be the main factor influencing institutionalization and self-renewal. The internal environment--the local school, and the local school's organization or central office, school board,…

  8. A factor analysis to detect factors influencing building national brand

    Directory of Open Access Journals (Sweden)

    Naser Azad

    Full Text Available Developing a national brand is one of the most important issues for development of a brand. In this study, we present factor analysis to detect the most important factors in building a national brand. The proposed study uses factor analysis to extract the most influencing factors and the sample size has been chosen from two major auto makers in Iran called Iran Khodro and Saipa. The questionnaire was designed in Likert scale and distributed among 235 experts. Cronbach alpha is calculated as 84%, which is well above the minimum desirable limit of 0.70. The implementation of factor analysis provides six factors including “cultural image of customers”, “exciting characteristics”, “competitive pricing strategies”, “perception image” and “previous perceptions”.

  9. Factors Influencing Prevention and Control of Malaria among ...

    African Journals Online (AJOL)

    AJRH Managing Editor

    investigate factors that influence malaria prevention and control practices among pregnant ... treatment of clinical cases and the promotion of ... influence their decision regarding malaria ..... have the ability to purchase anti-malaria drugs that.

  10. Factors influencing detail detectability in radiologic imaging

    International Nuclear Information System (INIS)

    Gurvich, A.M.

    1985-01-01

    The detectability of various details is estimated quantitatively from the essential technical parameters of the imaging system and additional influencing factors including viewing of the image. The analysis implies the formation of the input radiation distribution (contrast formation, influence of kVp). Noise, image contrast (gamma), modulation transfer function and contrast threshold of the observer are of different influence on details of different size. Thus further optimization of imaging systems and their adaption to specific imaging tasks are facilitated

  11. Factors influencing choice of paediatrics as a career among medical ...

    African Journals Online (AJOL)

    None of the male students but 12 of the female students (30%) considered gender distribution to be a factor influencing their career choice (p=0.046). Conclusion. This study indicates that paediatrics is popular among female students and that several factors influence choice of this specialty. Understanding these factors may ...

  12. Expression kinetics of key genes in the early innate immune response to Great Lakes viral hemorrhagic septicemia virus IVb infection in yellow perch (Perca flavescens)

    Science.gov (United States)

    Olson, Wendy; Emmenegger, Eveline; Glenn, Jolene; Simchick, Crystal; Winton, Jim; Goetz, Frederick

    2013-01-01

    The recently discovered strain of viral hemorrhagic septicemia virus, VHSV-IVb, represents an example of the introduction of an extremely pathogenic rhabdovirus capable of infecting a wide variety of new fish species in a new host-environment. The goal of the present study was to delineate the expression kinetics of key genes in the innate immune response relative to the very early stages of VHSV-IVb infection using the yellow perch (Perca flavescens) as a model. Administration of VHSV-IVb by IP-injection into juvenile yellow perch resulted in 84% cumulative mortality, indicating their high susceptibility to this disease. In fish sampled in the very early stages of infection, a significant up-regulation of Mx gene expression in the liver, as well as IL-1β and SAA activation in the head kidney, spleen, and liver was directly correlated to viral load. The potential down-regulation of Mx in the hematopoietic tissues, head kidney and spleen, may represent a strategy utilized by the virus to increase replication.

  13. Hierarchical and coupling model of factors influencing vessel traffic flow.

    Directory of Open Access Journals (Sweden)

    Zhao Liu

    Full Text Available Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system.

  14. Factors influencing cassava - pulp fermentation period for gari ...

    African Journals Online (AJOL)

    Factors influencing cassava - pulp fermentation period for gari processing among ... Result of probit model analysis at 5% significance level shows an R value ... Marital status (2.236**) and respondents' cultural influences (1.960**) were ...

  15. Quantitative influence of risk factors on blood glucose level.

    Science.gov (United States)

    Chen, Songjing; Luo, Senlin; Pan, Limin; Zhang, Tiemei; Han, Longfei; Zhao, Haixiu

    2014-01-01

    The aim of this study is to quantitatively analyze the influence of risk factors on the blood glucose level, and to provide theory basis for understanding the characteristics of blood glucose change and confirming the intervention index for type 2 diabetes. The quantitative method is proposed to analyze the influence of risk factors on blood glucose using back propagation (BP) neural network. Ten risk factors are screened first. Then the cohort is divided into nine groups by gender and age. According to the minimum error principle, nine BP models are trained respectively. The quantitative values of the influence of different risk factors on the blood glucose change can be obtained by sensitivity calculation. The experiment results indicate that weight is the leading cause of blood glucose change (0.2449). The second factors are cholesterol, age and triglyceride. The total ratio of these four factors reaches to 77% of the nine screened risk factors. And the sensitivity sequences can provide judgment method for individual intervention. This method can be applied to risk factors quantitative analysis of other diseases and potentially used for clinical practitioners to identify high risk populations for type 2 diabetes as well as other disease.

  16. Factors Influencing Healthcare Service Quality

    Directory of Open Access Journals (Sweden)

    Ali Mohammad Mosadeghrad

    2014-07-01

    Full Text Available Background The main purpose of this study was to identify factors that influence healthcare quality in the Iranian context. Methods Exploratory in-depth individual and focus group interviews were conducted with 222 healthcare stakeholders including healthcare providers, managers, policy-makers, and payers to identify factors affecting the quality of healthcare services provided in Iranian healthcare organisations. Results Quality in healthcare is a production of cooperation between the patient and the healthcare provider in a supportive environment. Personal factors of the provider and the patient, and factors pertaining to the healthcare organisation, healthcare system, and the broader environment affect healthcare service quality. Healthcare quality can be improved by supportive visionary leadership, proper planning, education and training, availability of resources, effective management of resources, employees and processes, and collaboration and cooperation among providers. Conclusion This article contributes to healthcare theory and practice by developing a conceptual framework that provides policy-makers and managers a practical understanding of factors that affect healthcare service quality.

  17. Variance of indoor radon concentration: Major influencing factors

    Energy Technology Data Exchange (ETDEWEB)

    Yarmoshenko, I., E-mail: ivy@ecko.uran.ru [Institute of Industrial Ecology UB RAS, Sophy Kovalevskoy, 20, Ekaterinburg (Russian Federation); Vasilyev, A.; Malinovsky, G. [Institute of Industrial Ecology UB RAS, Sophy Kovalevskoy, 20, Ekaterinburg (Russian Federation); Bossew, P. [German Federal Office for Radiation Protection (BfS), Berlin (Germany); Žunić, Z.S. [Institute of Nuclear Sciences “Vinca”, University of Belgrade (Serbia); Onischenko, A.; Zhukovsky, M. [Institute of Industrial Ecology UB RAS, Sophy Kovalevskoy, 20, Ekaterinburg (Russian Federation)

    2016-01-15

    Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niška Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niška Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed. - Highlights: • Influence of lithosphere and anthroposphere on variance of indoor radon is found. • Level-by-level analysis reduces GSD by a factor of 1.9. • Worldwide GSD is underestimated.

  18. FACTORS INFLUENCING YIELD SPREADS OF THE MALAYSIAN BONDS

    Directory of Open Access Journals (Sweden)

    Norliza Ahmad

    2009-01-01

    Full Text Available Malaysian bond market is developing rapidly but not much is understood in terms of macroeconomic factors that could influence the yield spread of the Ringgit Malaysian denominated bonds. Based on a multifactor model, this paper examines the impact of four macroeconomic factors namely: Kuala Lumpur Composite Index (KLCI, Industry Production Index (IPI, Consumer Price Index (CPI and interest rates (IR on bond yield spread of the Malaysian Government Securities (MGS and Corporate Bonds (CBs for a period from January 2001 to December 2008. The findings support the expected hypotheses that CPI and IR are the major drivers that influence the changes in MGS yield spreads. However IPI and KLCI have weak and no influence on MGS yield spreads respectively Whilst IR, CPI and IPI have significant influence on the yield spreads of CB1, CB2 and CB3, KLCI has significant influence only on the CB1 yield spread but not on CB2 and CB3 yield spreads.

  19. Factors influencing US medical students' decision to pursue surgery.

    Science.gov (United States)

    Schmidt, Lauren E; Cooper, Clairice A; Guo, Weidun Alan

    2016-06-01

    Interest and applications to surgery have steadily decreased over recent years in the United States. The goal of this review is to collect the current literature regarding US medical students' experience in surgery and factors influencing their intention to pursue surgery as a career. We hypothesize that multiple factors influence US medical students' career choice in surgery. Six electronic databases (PubMed, SCOPUS, Web of Science, Education Resources Information Center, Embase, and PsycINFO) were searched. The inclusion criteria were studies published after the new century related to factors influencing surgical career choice among US medical students. Factors influencing US medical student surgical career decision-making were recorded. A quality index score was given to each article selected to minimize risk of bias. We identified 38 relevant articles of more than 1000 nonduplicated titles. The factors influencing medical student decision for a surgical career were categorized into five domains: mentorship and role model (n = 12), experience (clerkship n = 9, stereotype n = 4), timing of exposure (n = 9), personal (lifestyle n = 8, gender n = 6, finance n = 3), and others (n = 2). This comprehensive systemic review identifies mentorship, experience in surgery, stereotypes, timing of exposure, and personal factors to be major determinants in medical students' decisions to pursue surgery. These represent areas that can be improved to attract applicants to general surgery residencies. Surgical faculty and residents can have a positive influence on medical students' decisions to pursue surgery as a career. Early introduction to the field of surgery, as well as recruitment strategies during the preclinical and clinical years of medical school can increase students' interest in a surgical career. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. A survey on critical factors influencing agricultural insurance

    Directory of Open Access Journals (Sweden)

    Ali Valipour

    2013-01-01

    Full Text Available Agricultural business is a very high-risk job and an increase demand for agricultural products from one side and steady increase in production cost and weather changes, on the other side, have motivated many to use insurance for agricultural products. Insurance plays an important role in influencing crop production and insured satisfaction or farmers. The purpose of this research is to find critical components in agricultural insurance. Based on an exploration of the literature review and interviews, the proposed study of this paper extracts 24 variables and using factor analysis, we select the most important factors, which are grouped in seven categories. The implementation of our factor analysis has revealed uncertainty, moderator, market equilibrium, risky environment, empowering factor, education, training, structural hazards and natural ecosystems as the most important factors influencing agricultural industry.

  1. Which factors influence women in the decision to breastfeed?

    Directory of Open Access Journals (Sweden)

    Cândida Canicali Primo

    Full Text Available Objective.Identify the factors that influence women in the decision to breastfeed. Methods. Integrative review. Information was gathered from original articles, case studies, theoretical studies, consensus and systematic reviews published between 2007-2013 in Spanish, Portuguese and English and recovered in the databases MEDLINE and LILACS. The descriptors used in this study were: breastfeeding, maternal behavior, risk factors, lactation and newborn. Results. Were included 30 articles, grouped into five categories. Factors influencing the decision of the breastfeeding woman are a convergence of breastfeeding's advantages, benefits and justifications, family, social and professional support, sociodemographic and clinical characteristics of women, personal experience and family tradition and personal choice. Conclusion. The decision to breastfeed by women is influenced by a convergence of factors. It is essential the role of nursing to encourage women in the decision to initiate and maintain breastfeeding her child.

  2. College factors that influence drinking.

    Science.gov (United States)

    Presley, Cheryl A; Meilman, Philip W; Leichliter, Jami S

    2002-03-01

    The purpose of this article is to examine the aspects of collegiate environments, rather than student characteristics, that influence drinking. Unfortunately, the existing literature is scant on this topic. A literature review of articles primarily published within the last 10 years, along with some earlier "landmark" studies of collegiate drinking in the United States, was conducted to determine institutional factors that influence the consumption of alcohol. In addition, a demonstration analysis of Core Alcohol and Drug Survey research findings was conducted to further elucidate the issues. Several factors have been shown to relate to drinking: (1) organizational property variables of campuses, including affiliations (historically black institutions, women's institutions), presence of a Greek system, athletics and 2- or 4-year designation; (2) physical and behavioral property variables of campuses, including type of residence, institution size, location and quantity of heavy episodic drinking; and (3) campus community property variables, including pricing and availability and outlet density. Studies, however, tend to look at individual variables one at a time rather than in combination (multivariate analyses). Some new analyses, using Core Alcohol and Drug Survey data sets, are presented as examples of promising approaches to future research. Given the complexities of campus environments, it continues to be a challenge to the field to firmly establish the most compelling institutional and environmental factors relating to high-risk collegiate drinking.

  3. Overview of factors influencing the secondary market

    International Nuclear Information System (INIS)

    Bleistine, P.A.

    1982-01-01

    The major factor influencing secondary trading for the last few years has been the large contractural commitments built up by consumers for reactor programs which have proven to be unrealistic. The situation has intensified as a result of utilities needing to generate capital through inventory liquidation or reductions. The flexibilities in most contracts are inadequate to match the types of external and/or internal factors faced by the industry. This situation also suggests the need for secondary markets to help the industry adjust to unforeseen difficulties. They are very active markets at this time, but their influence in relation to the long-term method of doing business should not be exaggerated

  4. Factors influencing job satisfaction of oncology nurses over time.

    Science.gov (United States)

    Cummings, Greta; Olson, Karin; Raymond-Seniuk, Christy; Lo, Eliza; Masaoud, Elmabrok; Bakker, Debra; Fitch, Margaret; Green, Esther; Butler, Lorna; Conlon, Michael

    2013-01-01

    In this study, we tested a structural equation model to examine work environment factors related to changes in job satisfaction of oncology nurses between 2004 and 2006. Relational leadership and good physician/nurse relationships consistently influenced perceptions of enough RNs to provide quality care, and freedom to make patient care decisions, which, in turn, directly influenced nurses' job satisfaction over time. Supervisor support in resolving conflict and the ability to influence patient care outcomes were significant influences on job satisfaction in 2004, whereas, in 2006, a clear philosophy of nursing had a greater significant influence. Several factors that influence job satisfaction of oncology nurses in Canada have changed over time, which may reflect changes in work environments and work life. These findings suggest opportunities to modify work conditions that could improve nurses' job satisfaction and work life.

  5. Factors influencing warfarin control in Australia and Singapore.

    Science.gov (United States)

    Bernaitis, Nijole; Ching, Chi Keong; Teo, Siew Chong; Chen, Liping; Badrick, Tony; Davey, Andrew K; Crilly, Julia; Anoopkumar-Dukie, Shailendra

    2017-09-01

    Warfarin is widely used for patients with non-valvular atrial fibrillation (NVAF). Variations in warfarin control, as measured by time in therapeutic range (TTR), have been reported across different regions and ethnicities, particularly between Western and Asian countries. However, there is limited data on comparative factors influencing warfarin control in Caucasian and Asian patients. Therefore, the aim of this study was to determine warfarin control and potential factors influencing this in patients with NVAF in Australia and Singapore. Retrospective data was collected for patients receiving warfarin for January to June 2014 in Australia and Singapore. TTR was calculated for individuals with mean patient TTR used for analysis. Possible influential factors on TTR were analysed including age, gender, concurrent co-morbidities, and concurrent medication. The mean TTR was significantly higher in Australia (82%) than Singapore (58%). At both sites, chronic kidney disease significantly lowered this TTR. Further factors influencing control were anaemia and ageWarfarin control was significantly higher in Australia compared to Singapore, however chronic kidney disease reduced control at both sites. The different levels of control in these two countries, together with patient factors further reducing control may impact on anticoagulant choice in these countries with better outcomes from warfarin in Australia compared to Singapore. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. An update of hydrologic conditions and distribution of selected constituents in water, eastern Snake River Plain aquifer and perched groundwater zones, Idaho National Laboratory, Idaho, emphasis 2009–11

    Science.gov (United States)

    Davis, Linda C.; Bartholomay, Roy C.; Rattray, Gordon W.

    2013-01-01

    groundwater at the ATR Complex during 2011 ranged from 4 to 54 mg/L. In 2011, sulfate concentrations in water samples from 11 aquifer wells in the south-central part of the INL equaled or exceeded the background concentration of sulfate and ranged from 40 to 167 mg/L. The greater-than-background concentrations in water from these wells probably resulted from sulfate disposal at the ATR Complex infiltration ponds or the old INTEC percolation ponds. In 2011, sulfate concentrations in water samples from two wells near the RWMC were greater than background levels and could have resulted from well construction techniques and (or) waste disposal at the RWMC. The vertical distribution of sulfate concentrations in three wells near the southern boundary of the INL was generally consistent with depth, and ranged between 19 and 25 mg/L. The maximum dissolved sulfate concentration in shallow perched groundwater near the ATR Complex was 400 mg/L in well CWP 1 in April 2011. During 2009–11, the maximum concentration of dissolved sulfate in deep perched groundwater at the ATR Complex was 1,550 mg/L in a well located west of the chemical-waste pond. In 2011, concentrations of nitrate in water from most wells at and near the INTEC exceeded the regional background concentrations of 1 mg/L and ranged from 1.6 to 5.95 mg/L. Concentrations of nitrate in wells south of INTEC and farther away from the influence of disposal areas and the Big Lost River show a general decrease in nitrate concentrations through time. During 2009–11, water samples from 30 wells were collected and analyzed for volatile organic compounds (VOCs). Six VOCs were detected. At least one and up to five VOCs were detected in water samples from 10 wells. The primary VOCs detected include carbon tetrachloride, chloroform, tetrachloroethylene, 1,1,1-trichloroethane, and trichloroethylene. In 2011, concentrations for all VOCs were less than their respective MCL for drinking water, except carbon tetrachloride in water from two

  7. Clinical factors influencing participation in society after successful kidney transplantation

    NARCIS (Netherlands)

    van der Mei, S.F.; Groothoff, J.W.; van Sonderen, E.L.P.; van den Heuvel, W.J.A.; de Jong, P.E.; van Son, W.J.

    2006-01-01

    Background. Little information is available on the degree of actual social functioning after successful kidney transplantation. Moreover, information on factors that influence participation in social activities is scarce. The aim of this study was to examine the influence of clinical factors on

  8. Factors influencing home care nurse intention to remain employed.

    Science.gov (United States)

    Tourangeau, Ann; Patterson, Erin; Rowe, Alissa; Saari, Margaret; Thomson, Heather; MacDonald, Geraldine; Cranley, Lisa; Squires, Mae

    2014-11-01

    To identify factors affecting Canadian home care nurse intention to remain employed (ITR). In developed nations, healthcare continues to shift into community settings. Although considerable research exists on examining nurse ITR in hospitals, similar research related to nurses employed in home care is limited. In the face of a global nursing shortage, it is important to understand the factors influencing nurse ITR across healthcare sectors. A qualitative exploratory descriptive design was used. Focus groups were conducted with home care nurses. Data were analysed using qualitative content analysis. Six categories of influencing factors were identified by home care nurses as affecting ITR: job characteristics; work structures; relationships/communication; work environment; nurse responses to work; and employment conditions. Findings suggest the following factors influence home care nurse ITR: having autonomy; flexible scheduling; reasonable and varied workloads; supportive work relationships; and receiving adequate pay and benefits. Home care nurses did not identify job satisfaction as a single concept influencing ITR. Home care nursing management should support nurse autonomy, allow flexible scheduling, promote reasonable workloads and create opportunities for team building that strengthen supportive relationships among home care nurses and other health team members. © 2013 John Wiley & Sons Ltd.

  9. Environmental factors influencing fluctuation of share prices on ...

    African Journals Online (AJOL)

    Environmental factors influencing fluctuation of share prices on Nigeria stock exchange market. ... What are these environmental variables that affect the fluctuation of share prices in Nigeria? ... The results show inflation, money supply, total deficits index of industrial production, interest rate and GDP influence stock prices.

  10. An investigation on factors influencing on human resources productivity

    Directory of Open Access Journals (Sweden)

    Masoumeh Seifi Divkolaii

    2014-05-01

    Full Text Available Human resources development is one of the most important components of any organization and detecting important factors influencing on human resources management plays essential role on the success of the firms. In this paper, we present an empirical investigation to determine different factors influencing productivity of human resources of Islamic Republic of Iran Broadcasting (IRIB in province of Mazandaran, Iran. The study uses analytical hierarchy process (AHP to rank 17 important factors and determines that personal characteristics were the most important factors followed by management related factors and environmental factors. In terms of personal characteristics, job satisfaction plays essential role on human resources development. In terms of managerial factors, paying attention on continuous job improvement by receiving appropriate training is the most important factor followed by welfare facilities for employees and using a system of reward/punishment in organization. Finally, in terms of environmental factors, occupational safety is number one priority followed by organizational rules and regulations.

  11. THE INFLUENCE OF CORPORATE SPECIFIC FACTORS UPON FINANCING DECISIONS

    Directory of Open Access Journals (Sweden)

    Lacatus Viorel-Dorin

    2013-07-01

    Full Text Available The purpose of this paper is to analyze the existing theories for the capital structure of a corporation and to determine the factors that influence the financing decisions of Romanian corporations. The gearing ratios vary a lot among Romanian corporations pointing out the fact that the internal specific factors are the ones with a greater impact upon their capital structure, and not the external factors. Our empiric research evaluates the determining factors for the debt ratio (total debt/total assets of some Romanian corporations, focusing on its explanatory variables by including them within simple and multiple econometric models. The panel data indicators computed for the companies in the Cluj area listed on the Bucharest Stock Exchange were evaluated with the OLS and FEM techniques.The results have been interpreted, pointing out that company size and asset turnover seem to have a positive influence upon the debt ratio of selected companies, while profitability and liquidity seem to influence the debt ratio of selected companies negatively.

  12. Maturity of hospital information systems: Most important influencing factors.

    Science.gov (United States)

    Vidal Carvalho, João; Rocha, Álvaro; Abreu, António

    2017-07-01

    Maturity models facilitate organizational management, including information systems management, with hospital organizations no exception. This article puts forth a study carried out with a group of experts in the field of hospital information systems management with a view to identifying the main influencing factors to be included in an encompassing maturity model for hospital information systems management. This study is based on the results of a literature review, which identified maturity models in the health field and relevant influencing factors. The development of this model is justified to the extent that the available maturity models for the hospital information systems management field reveal multiple limitations, including lack of detail, absence of tools to determine their maturity and lack of characterization for stages of maturity structured by different influencing factors.

  13. FACTORS INFLUENCING THE PURCHASE DECISION OF ORGANIC TOFU

    Directory of Open Access Journals (Sweden)

    Tantry Nugroho

    2015-09-01

    Full Text Available This study aimed to analyze the factors that influence consumers in making the decision to buy organic tofu. The theory of factors that influence the purchasing behavior developed by Kotler was used as the analytical tool, and these factors include cultural factors, social factors, personal factors, psychological factors and purchasing process. These data were collected through interview techniques and analyzed descriptively using multinomial logistic regression. The characteristics of respondents indicated the consumers who never bought organic tofu are mostly at the age of 26-35 years old and university graduates, do not work, have an expenditure from Rp 1 million to Rp 2.5 million, are highly knowledge, and have the highest scores on the perceptions on sustainable and environmentally friendly organic farming, health benefits, and a more expensive price. There are a number of factors that influence consumers in making purchase decisions of organic tofu including age, education, knowledge and product external factors. The consumers who are potentially interested in purchasing the organic tofu are at the age of 36–50 years old, university graduates, highly knowledgeable in food and organic tofu products, because the higher the education and knowledge, the greater the interest in buying the products, and they approved of the external products such as price, advertising, personal selling and places of selling which are also potentially equal. The managerial implications for the business agents of tofu organic product is that they must be more active in assuring the consumers that these products are good for them by creating a blog, an ad in the local paper, or a pamphlet containing information of the product.Keywords: purchase decision, logistic regression, organic tofu product, purchasing interest

  14. A Review of Factors Influencing Athletes' Food Choices.

    Science.gov (United States)

    Birkenhead, Karen L; Slater, Gary

    2015-11-01

    Athletes make food choices on a daily basis that can affect both health and performance. A well planned nutrition strategy that includes the careful timing and selection of appropriate foods and fluids helps to maximize training adaptations and, thus, should be an integral part of the athlete's training programme. Factors that motivate food selection include taste, convenience, nutrition knowledge and beliefs. Food choice is also influenced by physiological, social, psychological and economic factors and varies both within and between individuals and populations. This review highlights the multidimensional nature of food choice and the depth of previous research investigating eating behaviours. Despite numerous studies with general populations, little exploration has been carried out with athletes, yet the energy demands of sport typically require individuals to make more frequent and/or appropriate food choices. While factors that are important to general populations also apply to athletes, it seems likely, given the competitive demands of sport, that performance would be an important factor influencing food choice. It is unclear if athletes place the same degree of importance on these factors or how food choice is influenced by involvement in sport. There is a clear need for further research exploring the food choice motives of athletes, preferably in conjunction with research investigating dietary intake to establish if intent translates into practice.

  15. The effect of urbanization in an arid region: Formation of a perched water table that causes environmental damages

    Science.gov (United States)

    Karnieli, A.; Issar, A.; Wolf, M.

    1984-03-01

    Construction in a new neighborhood in the israeli town of Dimona, situated in an arid region in the south of the country (150 mm average annual rainfall), resulted in a rise in groundwater levels during the subsequent rainy seasons This caused flooding of shelter basements, soil sliding, and sagging which permanently damaged walls and buildings The neighborhood had been built on continental sands and marls blanketed by loess, on a valley slope near a rocky anticlinal dip-slope Subsurface studies, using piezometer holes and groundwater analyses, revealed the presence of sand lenses alternating with plastic marls, which act as seasonal aquifers with perched water tables Groundwaters obtain high SO{4/-2} and Cl- corrosivity through contact with these nonflushed marls of the Neogene valley fill (Hazeva Formation) The reasons for the rising of groundwater were found to be (a) artificial interference with the natural (pre-construction) drainage system—interception of the hillside runoff by building plots, roads, etc, (b) partial denudation of the loess blanket, increasing the local infiltration and the build-up of local, perched water tables, and (c) corrosion of concrete and steel pipelines, as well as foundations, by prolonged contact with corrosive groundwater, resulting in haphazard but massive leakage Guidelines are proposed for an environmental improvement plan, which would include terracing and planting of the watershed above town to increase evapotranspiration, lowering of the water table by pumping, and diverting the water to suburban parks (groves of saltresistant trees), and replacement of steel and cement pipes by a non-corrodable plastic pipe system

  16. Influence of Macroeconomic Factors on Residential Property ...

    African Journals Online (AJOL)

    Sultan

    exerted by macroeconomic factors on residential property returns in Abuja. The backward .... explanatory power and positive influence of employment and ...... Project. Management In Property Development: the Nigeria experience. Ibadan:.

  17. Factors Influencing Self Employment Media Service Providers ...

    African Journals Online (AJOL)

    Factors Influencing Self Employment Media Service Providers among Tertiary ... role stereotype and common business practices on media self employment in ... Sex, Psycho-social Characteristics, self Employment, Providing Media Services.

  18. Factors influencing societal response of nanotechnology : an expert stakeholder analysis

    OpenAIRE

    Gupta, N.; Fischer, A.R.H.; Lans, van der, I.A.; Frewer, L.J.

    2012-01-01

    Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an important role in how nanotechnology is developed and commercialised. This article aims to identify expert opinion on factors influencing societal response to applications of nanotechnology. Structured i...

  19. Factors influencing societal response of nanotechnology: an expert stakeholder analysis

    OpenAIRE

    Gupta, Nidhi; Fischer, Arnout R. H.; van der Lans, Ivo A.; Frewer, Lynn J.

    2012-01-01

    Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an important role in how nanotechnology is developed and commercialised. This article aims to identify expert opinion on factors influencing societal response to applications of nanotechnology. Structured i...

  20. Factors Influencing Choice of Inguinal Hernia Repair Technique

    African Journals Online (AJOL)

    This study sought to highlight factors that may influence ... Experienced peers play a major role in training on the various repair ... Reasons influencing choice of repair technique include training ... (after appendectomy) accounting for 10 to 15% of all surgical ..... in medical school [as undergraduate students or as residents].

  1. Factors Influencing Information and Communication Technology ...

    African Journals Online (AJOL)

    Information and communication technology (ICT) is a veritable tool for sustainable agricultural development in Nigeria. This paper analyzed the factors that influenced ICT use by women research scientists in the Universities of Agriculture in Nigeria. Simple random sampling technique was used to select 40 respondents per ...

  2. Factors Influencing Part-time Faculty Engagement With Online Nursing Programs.

    Science.gov (United States)

    Reneau, Margaret; Wallace, Cara; Claywell, Lora; Price, Jill; Burdi, Melissa; Trybulski, Joanne

    2018-03-28

    This research investigated factors that influenced the engagement of part-time faculty teaching in online nursing programs with their institutions. Of the 257 part-time faculty surveyed, the most significant factor was being supported in decisions regarding student issues, followed by institutional commitment to quality online education. Compensation was moderately influential; a negative factor was requiring too frequent meetings. Understanding factors that influence the engagement of part-time faculty teaching in online nursing programs can help leaders of online programs attract and retain experienced, highly skilled faculty.

  3. FACTORS INFLUENCING BRAND EQUITY OF BALI AS A TOURISM DESTINATION

    Directory of Open Access Journals (Sweden)

    I Ketut Surya Diarta

    2016-03-01

    Full Text Available Globally, competition among tourism destinations is more stringent in getting foreign tourists, including Bali. One effort to win the competition is increasing destination brand equity through maintaining its influencing factors and gaining tourist positive behavior toward destination. This effort, in long run, will increase and stabilize destination revenue and sustainability. This research aims to analyze factors influencing brand equity of Bali as a tourism destination. This research was conducted in Bali’s five major tourism objects. The 240 foreign tourists were chosen as respondents through convenience sampling technique. Data were analyzed using factor analysis. The results showed that factors that significantly influenced Bali brand equity were: symbolic and experiential benefit factor, direct and indirect destinations attributes, destination reliability and tangibility, assurance and empathy, brand destinations recognition and recall, destinations common psychological attributes, destination common functional attributes, unique functional attributes, behavioral loyalty, destination awareness, and attitudinal loyalty. Given the fluctuative nature of brand equity, Bali needs a consistent effort to maintain or to enhance brand equity of Bali as a tourism destination. Maintaining the dominant factors that influence the strength of brand equity can be used as a basis to develop destination branding strategy to expand market segment,  choose the right target market, and anchoring destination position in world market competition.

  4. Factors That Influence the Practice of Elective Induction of Labor

    Science.gov (United States)

    Moore, Jennifer; Low, Lisa Kane

    2012-01-01

    Elective induction of labor has been linked to increased rates of prematurity and rising rates of cesarean birth. The purpose of this investigation was to evaluate current trends in induction of labor scholarship focusing on evidence-based factors that influence the practice of elective induction. A key word search was conducted to identify studies on the practice of elective induction of labor. Analysis of the findings included clustering and identification of recurrent themes among the articles with 3 categories being identified. Under each category, the words/phrases were further clustered until a construct could be named. A total of 49 articles met inclusion criteria: 7 patient, 6 maternity care provider, and 4 organization factors emerged. Only 4 of the articles identified were evidence based. Patient factors were divided into preferences/convenience, communication, fear, pressure/influence, trust, external influences, and technology. Provider factors were then divided into practice preferences/convenience, lack of information, financial incentives, fear, patient desire/demand, and technology. Organization factors were divided into lack of enforcement/accountability, hospital culture, scheduling of staff, and market share issues. Currently, there is limited data-based information focused on factors that influence elective induction of labor. Despite patient and provider convenience/preferences being cited in the literature, the evidence does not support this practice. PMID:22843006

  5. Factors Influencing Tacit Knowledge in Construction

    Directory of Open Access Journals (Sweden)

    Jawahar Nesan

    2012-11-01

    Full Text Available Increased complexity of the construction business and consequentuse of new management concepts and technologies ledconstruction organisations to focus more on the transfer of explicitknowledge. However, it is the tacit knowledge that determinesthe construction companies’ competitiveness in a business thatis driven by turbulent market conditions and customers’ everincreasingdemands. This paper highlights the importance of tacitknowledge sharing in construction, explores the challenges andopportunities to efficiently share tacit knowledge, and based on theliterature review identifies some critical factors that influence tacitknowledge in construction. It is argued that employees’ knowledgesharing (learning behaviours are influenced by work practices thatare borne by respective organisational behaviours. Organisational,cultural, and project characteristics that facilitate knowledgesharing among construction employees are explored and thepractices that influence the construction employee behaviour insharing tacit knowledge are highlighted.

  6. Multilevel factors influencing preterm birth in an urban setting

    Directory of Open Access Journals (Sweden)

    Saba W. Masho

    2014-01-01

    Full Text Available Racial disparity in preterm is a major problem in the US. Although significant strides have been made in identifying some of the risk factors, the complexities between community and individual factors are not understood. This study examines the influence of individual and community level factors affecting preterm birth among Black and White women in an urban setting. A 10-year live birth registry dataset from a mid-sized, racially diverse city was analyzed (N = 30,591. Data were geocoded and merged with block group level Census data. Five hierarchical models were examined using PROC GLIMMIX. Education, illicit drug use, pregnancy complications, previous preterm birth, paternal presence, inadequate and adequate plus prenatal care, and poverty were associated with preterm births in both Blacks and Whites. In Black women, increasing maternal age, maternal smoking, and a previous infant death were significant predictors of preterm births, which was not the case for White women. Residing in medium or high poverty neighborhoods resulted in 19% and 28% higher odds, respectively, of preterm birth for Black women. In addition to individual level factors, neighborhood poverty is an important risk factor influencing preterm birth. It is essential to engage multisectoral agencies in addressing factors influencing preterm birth.

  7. Factors influencing purchase intention towards consumer-to-consumer e-commerce

    OpenAIRE

    Muhammad Dachyar; Liska Banjarnahor

    2017-01-01

    Purpose: This study explores factors that influence consumer’s purchase intention at three consumer-to-consumer (C2C) e-commerce companies in Indonesia. Design/methodology: 5 Expert opinions are used to determine the indicators of each factor and the Structural Equation Modelling (SEM) method is used to analyze the empirical data of 400 respondents for each company. Findings: It is found different significant factors that influence customer’s purchase intention in each compa...

  8. Socio-Economic Factors Influencing Entrepreneurship Among ...

    African Journals Online (AJOL)

    Socio-Economic Factors Influencing Entrepreneurship Among Women In Fishing Communities In Ondo State, Nigeria. ... The study found that overall entrepreneurial rating of the study group is low, essential input can not be easily gotten in the area, the respondents has large household size thereby had a large dependents ...

  9. Factors Influencing Donor Partnership Effectiveness | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-11-03

    Nov 3, 2010 ... A two-dimensional tool probing eight factors that influence partnership performance was developed, and used in conjunction with a Partnering Process Model, to guide the preparation of the case studies. The incorporation of the temporality dimension is quite novel and adds to the understanding and ...

  10. How does exposure to nickel and cadmium affect the transcriptome of yellow perch (Perca flavescens) – Results from a 1000 candidate-gene microarray

    International Nuclear Information System (INIS)

    Bougas, Bérénice; Normandeau, Eric; Pierron, Fabien; Campbell, Peter G.C.; Bernatchez, Louis; Couture, Patrice

    2013-01-01

    Highlights: •The transcriptional responses of Perca flavescens to both metal and non metal stressors were measured with a 1000 candidate-gene microarray. •475, 287 and 176 genes were differentially transcribed depending on temperature, Ni and Cd concentrations, respectively. •Genes involved in iron metabolism, transcriptional and translational processes, vitamin metabolism, blood coagulation, and calcium transport were impacted by metals. •The developed microarray contributes to a better characterization of the impact of different stressors on the transcriptome. -- Abstract: The molecular mechanisms underlying nickel (Ni) and cadmium (Cd) toxicity and their specific effects on fish are poorly understood. Documenting gene transcription profiles offers a powerful approach toward identifying the molecular mechanisms affected by these metals and to discover biomarkers of their toxicity. However, confounding environmental factors can complicate the interpretation of the results and the detection of biomarkers for fish captured in their natural environment. In the present study, a 1000 candidate-gene microarray, developed from a previous RNA-seq study on a subset of individual fish from contrasting level of metal contamination, was used to investigate the transcriptional response to metal (Ni and Cd) and non metal (temperature, oxygen, and diet) stressors in yellow perch (Perca flavescens). Specifically, we aimed at (1) identifying transcriptional signatures specific to Ni and Cd exposure, (2) investigating the mechanisms of their toxicity, and (3) developing a predictive tool to identify the sublethal effects of Ni and Cd contaminants in fish sampled from natural environments. A total of 475 genes displayed significantly different transcription levels when temperature varied while 287 and 176 genes were differentially transcribed at different concentrations of Ni and Cd, respectively. These metals were found to mainly affect the transcription level of genes

  11. How does exposure to nickel and cadmium affect the transcriptome of yellow perch (Perca flavescens) – Results from a 1000 candidate-gene microarray

    Energy Technology Data Exchange (ETDEWEB)

    Bougas, Bérénice, E-mail: Berenice.Bougas@ete.inrs.ca [Institut National de la Recherche Scientifique, Centre INRS Eau Terre et Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada); Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Normandeau, Eric [Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Pierron, Fabien [Université de Bordeaux, EPOC, UMR 5805, F-33400 Talence (France); CNRS, EPOC, UMR 5805, F-33400 Talence (France); Campbell, Peter G.C. [Institut National de la Recherche Scientifique, Centre INRS Eau Terre et Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada); Bernatchez, Louis [Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Couture, Patrice [Institut National de la Recherche Scientifique, Centre INRS Eau Terre et Environnement, 490, rue de la Couronne, Québec, Québec G1K 9A9 (Canada)

    2013-10-15

    Highlights: •The transcriptional responses of Perca flavescens to both metal and non metal stressors were measured with a 1000 candidate-gene microarray. •475, 287 and 176 genes were differentially transcribed depending on temperature, Ni and Cd concentrations, respectively. •Genes involved in iron metabolism, transcriptional and translational processes, vitamin metabolism, blood coagulation, and calcium transport were impacted by metals. •The developed microarray contributes to a better characterization of the impact of different stressors on the transcriptome. -- Abstract: The molecular mechanisms underlying nickel (Ni) and cadmium (Cd) toxicity and their specific effects on fish are poorly understood. Documenting gene transcription profiles offers a powerful approach toward identifying the molecular mechanisms affected by these metals and to discover biomarkers of their toxicity. However, confounding environmental factors can complicate the interpretation of the results and the detection of biomarkers for fish captured in their natural environment. In the present study, a 1000 candidate-gene microarray, developed from a previous RNA-seq study on a subset of individual fish from contrasting level of metal contamination, was used to investigate the transcriptional response to metal (Ni and Cd) and non metal (temperature, oxygen, and diet) stressors in yellow perch (Perca flavescens). Specifically, we aimed at (1) identifying transcriptional signatures specific to Ni and Cd exposure, (2) investigating the mechanisms of their toxicity, and (3) developing a predictive tool to identify the sublethal effects of Ni and Cd contaminants in fish sampled from natural environments. A total of 475 genes displayed significantly different transcription levels when temperature varied while 287 and 176 genes were differentially transcribed at different concentrations of Ni and Cd, respectively. These metals were found to mainly affect the transcription level of genes

  12. Community Factors Influencing Birth Spacing among Married ...

    African Journals Online (AJOL)

    AJRH Managing Editor

    level factors on birth spacing behaviour in Uganda and Zimbabwe, to ... environments as potential influences on birth spacing ..... health: multivariable cross-country analysis, MACRO ... Equity monitoring for social marketing: Use of wealth.

  13. Factors Influencing Adoption of Cocoa Technologies Disseminated ...

    African Journals Online (AJOL)

    Factors Influencing Adoption of Cocoa Technologies Disseminated by Olam Organisation in ... Journal of Agricultural Research and Development ... level, household size, no of farm family assisting on the farm, management system adopted, ...

  14. Habitat factors influencing the distribution of Cymbopogon validus in ...

    African Journals Online (AJOL)

    Habitat factors influencing the distribution of Cymbopogon validus in Mkambati Game Reserve, Transkei. ... disturbance; game reserve; grassland; grasslands; habitat conditions; habitat factors; mkambati game ... AJOL African Journals Online.

  15. Factors that influence household and individual clothing expenditure ...

    African Journals Online (AJOL)

    S Blignaut

    Contributing factors are the growth of low-priced apparel ... determine which factors influence household and individual ... explicitly deals with this concept. .... The income elasticity for clothing for the two-parent ..... Nelson (1989) found that mothers with less than a .... fashion consciousness and style preferences should.

  16. Factors influencing internal color of cooked meats.

    Science.gov (United States)

    Suman, Surendranath P; Nair, Mahesh N; Joseph, Poulson; Hunt, Melvin C

    2016-10-01

    This manuscript overviews the pertinent research on internal color of uncured cooked meats, biochemical processes involved in meat cookery, and fundamental mechanisms governing myoglobin thermal stability. Heat-induced denaturation of myoglobin, responsible for the characteristic dull-brown color of cooked meats, is influenced by a multitude of endogenous (i.e., pH, muscle source, species, redox state) and exogenous (i.e., packaging, ingredients, storage) factors. The interactions between these factors critically influence the internal cooked color and can confuse the consumers, who often perceive cooked color to be a reliable indicator for doneness and safety. While certain phenomena in cooked meat color are cosmetic in nature, others can mislead consumers and result in foodborne illnesses. Research in meat color suggests that processing technologies and cooking practices in industry as well as households influence the internal cooked color. Additionally, the guidelines of many international public health and regulatory authorities recommend using meat thermometers to determine safe cooking endpoint temperature and to ensure product safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Factors influencing selection of office furniture by corporations and universities

    Science.gov (United States)

    R. Bruce Anderson

    1976-01-01

    Evaluation of the factors that influence the selection of office furniture by large corporations and universities shows that quality, appearance, and purchase price have the most important influence on the purchase decision. The intended use of the furniture and the appearance of the furniture were the key factors in the purchase of wooden furniture.

  18. Cerebrospinal Fluid Pressure: Revisiting Factors Influencing Optic Nerve Head Biomechanics

    Science.gov (United States)

    Hua, Yi; Voorhees, Andrew P.; Sigal, Ian A.

    2018-01-01

    Purpose To model the sensitivity of the optic nerve head (ONH) biomechanical environment to acute variations in IOP, cerebrospinal fluid pressure (CSFP), and central retinal artery blood pressure (BP). Methods We extended a previously published numerical model of the ONH to include 24 factors representing tissue anatomy and mechanical properties, all three pressures, and constraints on the optic nerve (CON). A total of 8340 models were studied to predict factor influences on 98 responses in a two-step process: a fractional factorial screening analysis to identify the 16 most influential factors, followed by a response surface methodology to predict factor effects in detail. Results The six most influential factors were, in order: IOP, CON, moduli of the sclera, lamina cribrosa (LC) and dura, and CSFP. IOP and CSFP affected different aspects of ONH biomechanics. The strongest influence of CSFP, more than twice that of IOP, was on the rotation of the peripapillary sclera. CSFP had similar influence on LC stretch and compression to moduli of sclera and LC. On some ONHs, CSFP caused large retrolamina deformations and subarachnoid expansion. CON had a strong influence on LC displacement. BP overall influence was 633 times smaller than that of IOP. Conclusions Models predict that IOP and CSFP are the top and sixth most influential factors on ONH biomechanics. Different IOP and CSFP effects suggest that translaminar pressure difference may not be a good parameter to predict biomechanics-related glaucomatous neuropathy. CON may drastically affect the responses relating to gross ONH geometry and should be determined experimentally. PMID:29332130

  19. Factors That Influence Technology Integration in the Classroom

    Science.gov (United States)

    Montgomery, Maureen C.

    2017-01-01

    Education is one area where the use of technology has had great impact on student learning. The integration of technology in teaching and learning can significantly influence the outcome of education in the classroom. However, there are a myriad of factors that influence technology integration in the classroom. The purpose of this study was to…

  20. Factors influencing the, selection of state office furniture

    Science.gov (United States)

    R. Bruce Anderson; R. Bruce Anderson

    1973-01-01

    Evaluation of the factors influencing the selection of office furniture by nine state governments shows that quality and purchase price have the most important influence on the purchase decision. The intended use of the furniture and the purchasing regulations of the states were key f8CbrS in the use of wood furniture.

  1. Relative importance of natural and anthropogenic factors influencing karst rocky desertification

    Science.gov (United States)

    Xu, Erqi; Zhang, Hongqi

    2017-04-01

    As the most severe ecological issue in southwest China, karst rocky desertification (KRD) has both threatened and constrained regional sustainable development. Comprehensively understanding the relationship between the evolution of KRD and relevant driving data would provide more information to combat KRD in such complex karst environments. Past studies have been limited in quantifying the relative importance of driving factors influencing fine-scale KRD evolution, and have also lacked insight into their interactive impacts. To address these issues, we have used geographical information system techniques and a geographical detector model to explore the spatial consistency of driving factors and their interactions in relation to the evolution of KRD. Changshun County in China was selected as a representative area for the study. Nine relevant driving factors, including both natural and anthropogenic factors, were studied in regard to their relationships with KRD transformation between 2000 and 2010. Our results demonstrate the relative importance of driving data in influencing the improvement and deterioration of KRD. Lithology, soil type and road influence are identified as the leading factors. Interestingly, to our study at least, there is no significant difference between the impacts of natural and anthropogenic factors influencing KRD improvement, and even natural factors have a higher impact on KRD deterioration. Factors were found to enhance the influence of each other for KRD transformation. In particular, the results show a non-linearly enhanced effect between driving factors, which significantly aggravates KRD. New information found in our study helps to effectively control and restore areas afflicted by KRD.

  2. Assessment of Factors Influencing Beneficiary Participation in ...

    African Journals Online (AJOL)

    ISSN 0794-5698. Assessment of Factors Influencing Beneficiary Participation in Fadama II Project ... project implementation (80%) in the stages of project development. Women .... the project as they appeared to have more family burden to ...

  3. Psychosocial factors for influencing healthy aging in adults in Korea.

    Science.gov (United States)

    Han, KyungHun; Lee, YunJung; Gu, JaSung; Oh, Hee; Han, JongHee; Kim, KwuyBun

    2015-03-07

    Healthy aging includes physical, psychological, social, and spiritual well-being in later years. The purpose of this study is to identify the psychosocial factors influencing healthy aging and examining their socio-demographic characteristics. Perceived health status, depression, self-esteem, self-achievement, ego-integrity, participation in leisure activities, and loneliness were identified as influential factors in healthy aging. 171 Korean adults aged between 45 and 77 years-old participated in the study. Self-reporting questionnaires were used, followed by descriptive statistics and multiple regressions as inferential statistical analyses. There were significant differences between participants' general characteristics: age, education, religion, housing, hobby, and economic status. The factors related to healthy aging had positive correlation with perceived health status, self-esteem, self-achievements, and leisure activities, and negative correlation with depression and loneliness. The factors influencing healthy aging were depression, leisure activities, perceived health status, ego integrity, and self-achievements. These factors were able to explain 51.9%. According to the results, depression is the factor with the greatest influence on healthy aging. Perceived health status, ego integrity, self-achievement, self-esteem, participation of leisure activities were also influential on healthy aging as beneficial factors.

  4. A brief review of salient factors influencing adult eating behaviour.

    Science.gov (United States)

    Emilien, Christine; Hollis, James H

    2017-12-01

    A better understanding of the factors that influence eating behaviour is of importance as our food choices are associated with the risk of developing chronic diseases such as obesity, CVD, type 2 diabetes or some forms of cancer. In addition, accumulating evidence suggests that the industrial food production system is a major contributor to greenhouse gas emission and may be unsustainable. Therefore, our food choices may also contribute to climate change. By identifying the factors that influence eating behaviour new interventions may be developed, at the individual or population level, to modify eating behaviour and contribute to society's health and environmental goals. Research indicates that eating behaviour is dictated by a complex interaction between physiology, environment, psychology, culture, socio-economics and genetics that is not fully understood. While a growing body of research has identified how several single factors influence eating behaviour, a better understanding of how these factors interact is required to facilitate the developing new models of eating behaviour. Due to the diversity of influences on eating behaviour this would probably necessitate a greater focus on multi-disciplinary research. In the present review, the influence of several salient physiological and environmental factors (largely related to food characteristics) on meal initiation, satiation (meal size) and satiety (inter-meal interval) are briefly discussed. Due to the large literature this review is not exhaustive but illustrates the complexity of eating behaviour. The present review will also highlight several limitations that apply to eating behaviour research.

  5. Alternative Administrative Certification: Socializing Factors Influencing Program Choice

    Science.gov (United States)

    Bickmore, Dana L.; Bickmore, Steven T.; Raines, Sarah

    2013-01-01

    This study used an organizational socialization lens to examine factors influencing participants' decision to pursue the principalship and choice to engage in an alternate administration certification program. Through an analysis of participant focus groups and interviews, factors emerged from the codes that were compared with dimensions of…

  6. Influence Factors of the Economic Development Level Across European Countries

    OpenAIRE

    Diana Ioana POPA

    2016-01-01

    The economic development level of a country refers to the measure of the progress in an economy that could be measured, especially through GDP or GDP per capita. The level of these indicators can be influenced by many factors as a large scale, from social and economical to environmental and government policies factors. The paper aims to investigate some of these influence factors of the economic development level, represented in this case by GDP per capita, across European countries in the...

  7. LITERATURE REVIEW ON FACTORS INFLUENCING MILK PURCHASE BEHAVIOUR

    Directory of Open Access Journals (Sweden)

    Klaudia Kurajdova

    2015-01-01

    Full Text Available In today’s highly informed, competitive and saturated market, a key to success of any business depends on knowing consumer and his consumption patterns and recognizing and understanding factors influencing his decision-making for the purpose of developing an attractive offer of products, supporting services, communication means and other marketing tools that would fit like a glue to customer’s needs. Study of consumer behaviour belongs to a group of very wide and strong subjects of marketing attention and its examination requires ongoing approach. Milk, as one category of dairy products, belongs to the group of basic daily-consumed products characterized by relatively high purchase frequency. On the other hand, its production and consumption is experiencing certain negative trend in Slovakia what inevitably calls for a scientific attention and examination in order to reverse this unfavourable development having a negative impact on the milk companies in Slovakia. Therefore, we focus our attention on studying various factors influencing consumers when purchasing this specific product. Our research in this stage resulted in the compilation of literature review on factors influencing consumers when purchasing milk and determination of boundaries and guidelines for our future research activity

  8. How modifiable factors influence parental decision-making about organ donation.

    Science.gov (United States)

    Luberda, Kamila; Cleaver, Karen

    2017-11-07

    A global shortage of organs from children and adults available for transplantation is compounded by the failure of next of kin to consent for organs to be donated after death. Non-modifiable and modifiable factors influence decision-making in this area. Modifiable factors are of interest when examining families' decision-making about the donation of organs from their deceased child. A scoping review was undertaken to determine how modifiable factors influence parental decision-making about organ donation. Thematic analysis identified two themes: interactions with healthcare professionals and pre-disposition to organ donation. Satisfaction with experiences of hospital care, the information provided and the way it was communicated, as well as interactions pertaining to emotional support were all found to be modifiable factors that influenced decision making. Likewise, a predisposition to organ donation and knowing the deceased's wishes were associated with the consent decision. Nurses working in critical care environments need to be able to support parents during this difficult time. This article aims to raise awareness of modifiable factors that influence parental decision-making, highlighting their relevance for children's nursing practice. ©2017 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

  9. Emergency department crowding: factors influencing flow.

    Science.gov (United States)

    Arkun, Alp; Briggs, William M; Patel, Sweha; Datillo, Paris A; Bove, Joseph; Birkhahn, Robert H

    2010-02-01

    THE OBJECTIVE OF THIS STUDY WAS TO EVALUATE THOSE FACTORS, BOTH INTRINSIC AND EXTRINSIC TO THE EMERGENCY DEPARTMENT (ED) THAT INFLUENCE TWO SPECIFIC COMPONENTS OF THROUGHPUT: "door-to-doctor" time and dwell time. We used a prospective observational study design to determine the variables that played a significant role in determining ED flow. All adult patients seen or waiting to be seen in the ED were observed at 8pm (Monday-Friday) during a three-month period. Variables measured included daily ED volume, patient acuity, staffing, ED occupancy, daily admissions, ED boarder volume, hospital volume, and intensive care unit volume. Both log-rank tests and time-to-wait (survival) proportional-hazard regression models were fitted to determine which variables were most significant in predicting "door-to-doctor" and dwell times, with full account of the censoring for some patients. We captured 1,543 patients during our study period, representing 27% of total daily volume. The ED operated at an average of 85% capacity (61-102%) with an average of 27% boarding. Median "door-to-doctor" time was 1.8 hours, with the biggest influence being triage category, day of the week, and ED occupancy. Median dwell time was 5.5 hours with similar variable influences. The largest contributors to decreased patient flow through the ED at our institution were triage category, ED occupancy, and day of the week. Although the statistically significant factors influencing patient throughput at our institution involve problems with inflow, an increase in ED occupancy could be due to substantial outflow obstruction and may indicate the necessity for increased capacity both within the ED and hospital.

  10. Waterborne cadmium and nickel impact oxidative stress responses and retinoid metabolism in yellow perch

    International Nuclear Information System (INIS)

    Defo, Michel A.; Bernatchez, Louis; Campbell, Peter G.C.; Couture, Patrice

    2014-01-01

    Highlights: • Cd and Ni affected indicators of retinoid metabolism and oxidative stress in fish. • Liver rdh-2 transcription levels increase in fish exposed to waterborne Cd. • Liver REH and LdRAT activities increase with increasing kidney Cd concentration. • Changes at molecular levels do not always mean changes at the functional levels. • Multi-level biological approaches are needed when assessing fish metal toxicology. - Abstract: In this experiment, we studied the transcriptional and functional (enzymatic) responses of yellow perch (Perca flavescens) to metal stress, with a focus on oxidative stress and vitamin A metabolism. Juvenile yellow perch were exposed to two environmentally relevant concentrations of waterborne cadmium (Cd) and nickel (Ni) for a period of 6 weeks. Kidney Cd and Ni bioaccumulation significantly increased with increasing metal exposure. The major retinoid metabolites analyzed in liver and muscle decreased with metal exposure except at high Cd exposure where no variation was reported in liver. A decrease in free plasma dehydroretinol was also observed with metal exposure. In the liver of Cd-exposed fish, both epidermal retinol dehydrogenase 2 transcription level and corresponding enzyme activities retinyl ester hydrolase and lecithin dehydroretinyl acyl transferase increased. In contrast, muscle epidermal retinol dehydrogenase 2 transcription level decreased with Cd exposure. Among antioxidant defences, liver transcription levels of catalase, microsomal glutathione-S-transferase-3 and glucose-6-phosphate dehydrogenase were generally enhanced in Cd-exposed fish and this up-regulation was accompanied by an increase in the activities of corresponding enzymes, except for microsomal glutathione-S-transferase. No consistent pattern in antioxidant defence responses was observed between molecular and biochemical response when fish were exposed to Ni, suggesting a non-synchronous response of antioxidant defence in fish exposed to

  11. Waterborne cadmium and nickel impact oxidative stress responses and retinoid metabolism in yellow perch

    Energy Technology Data Exchange (ETDEWEB)

    Defo, Michel A. [Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9 (Canada); Bernatchez, Louis [Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec G1V 0A6 (Canada); Campbell, Peter G.C. [Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9 (Canada); Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca [Institut national de la recherche scientifique (INRS), Centre Eau Terre Environnement, 490 de la Couronne, Québec, Québec G1K 9A9 (Canada)

    2014-09-15

    Highlights: • Cd and Ni affected indicators of retinoid metabolism and oxidative stress in fish. • Liver rdh-2 transcription levels increase in fish exposed to waterborne Cd. • Liver REH and LdRAT activities increase with increasing kidney Cd concentration. • Changes at molecular levels do not always mean changes at the functional levels. • Multi-level biological approaches are needed when assessing fish metal toxicology. - Abstract: In this experiment, we studied the transcriptional and functional (enzymatic) responses of yellow perch (Perca flavescens) to metal stress, with a focus on oxidative stress and vitamin A metabolism. Juvenile yellow perch were exposed to two environmentally relevant concentrations of waterborne cadmium (Cd) and nickel (Ni) for a period of 6 weeks. Kidney Cd and Ni bioaccumulation significantly increased with increasing metal exposure. The major retinoid metabolites analyzed in liver and muscle decreased with metal exposure except at high Cd exposure where no variation was reported in liver. A decrease in free plasma dehydroretinol was also observed with metal exposure. In the liver of Cd-exposed fish, both epidermal retinol dehydrogenase 2 transcription level and corresponding enzyme activities retinyl ester hydrolase and lecithin dehydroretinyl acyl transferase increased. In contrast, muscle epidermal retinol dehydrogenase 2 transcription level decreased with Cd exposure. Among antioxidant defences, liver transcription levels of catalase, microsomal glutathione-S-transferase-3 and glucose-6-phosphate dehydrogenase were generally enhanced in Cd-exposed fish and this up-regulation was accompanied by an increase in the activities of corresponding enzymes, except for microsomal glutathione-S-transferase. No consistent pattern in antioxidant defence responses was observed between molecular and biochemical response when fish were exposed to Ni, suggesting a non-synchronous response of antioxidant defence in fish exposed to

  12. Factors influencing thermal tolerances of individual organisms

    International Nuclear Information System (INIS)

    Hutchison, V.H.

    1976-01-01

    The diversity of experimental methods and terminology employed by investigators to measure the effects of high temperatures on individual organisms, plus the often overlooked complexities of the holocoenotic environment, has often led to disconcerting conclusions. A plea is made for standardization of testing methods and for a wider appreciation of factors that may alter thermal tolerances. The influence of elevated temperature is grouped into three categories, lethal effects, controlling effects, and directive effects, all of which should be considered in assessing the impact of thermal effluent on organisms. In addition, the terminology (acclimation, acclimatization, adaptation, habituation, lethal temperature, critical thermal maximum, etc.) needs standardized definitions. The important factors influencing thermal effects on organisms include photoperiod, seasonal and daily cycles, geographic variation, diet, sex, breeding condition, age, life-cycle stage, salinity, chemicals, body water content and partitioning, oxygen supply, pH, innate and learned behavior, history of thermal exposure, sublethal exposure to limiting factors, and experimental methods. Examples of most of these are given to illustrate the role of temperature in the holocoenotic environmental complex of individual organisms

  13. Factors influencing the pattern of malnutrition among acutely ill ...

    African Journals Online (AJOL)

    Factors influencing the pattern of malnutrition among acutely ill children presenting in ... height/length) measurements and z-scores calculated for the individual nutritional ... The factors associated with malnutrition included early introduction of ...

  14. Factors Influencing the Adoption of Minimally Invasive Surgery ...

    African Journals Online (AJOL)

    Background: Cost is a major concern for delivery of minimally invasive surgical technologies due to the nature of resources required. It is unclear whether factors extrinsic to technology availability impact on this uptake. Objectives: To establish the influence of institutional, patient and surgeon-related factors in the adoption of ...

  15. Factors Influencing Indonesian Internet Users Intention on Buying Books Online

    Directory of Open Access Journals (Sweden)

    Beatrik Messah

    2003-09-01

    Full Text Available The purpose of this research is to discover and analyse factors influencing Indonesian internet users intention on buying books online. Certain factors will be investigated are demographic, features, convenience, web design, and security. This research used questionaires to obtain data from the respondents. After the data collected, SPSS software is used to process the data with using Chi-Square test. The result found that features, convenience, and security factors of online bookstores and level of education, income, and occupation of the Indonesian Internet Users influence the people intention on buying books online. In the other hand, web design of the online bookstores and the age of the Indonesian internet users have no influence on their intention on buying books online.

  16. Factors influencing eating attitudes in secondary-school girls in ...

    African Journals Online (AJOL)

    Family, especially maternal, factors play a role in determining eating attitudes. Peer and media (television) factors are not significantly influential. The findings provide preliminary data on factors that influence eating attrtudes in a group at risk for the development of eating disorders. The findings have implications for the ...

  17. Iranian nurses self-perception -- factors influencing nursing image.

    Science.gov (United States)

    Varaei, Shokoh; Vaismoradi, Mojtaba; Jasper, Melanie; Faghihzadeh, Soghrat

    2012-05-01

    The purpose of this study was to describe the perspectives of Iranian nurses regarding factors influencing nursing image. Nursing image is closely tied to the nurse's role and identity, influencing clinical performance, job satisfaction and quality of care. Images of nursing and nurses are closely linked to the cultural context in which nursing is practised, hence, this study explores how Iranian nurses perceive the factors that influence their own image. A descriptive study using a survey design was conducted with 220 baccalaureate qualified nurses working in four teaching hospitals in an urban area of Iran. A Nursing Image Questionnaire was used and analysed using descriptive and inferential statistics. In the domains of 'characteristics required for entry to work', 'social role characteristics of nursing' and 'prestige, economic and social status, and self image' the nurses had negative images. 'Reward' and 'opportunity for creativity and originality' were factors that least influenced choosing nursing as a career. The presence of a nurse in the family and working in the hospital had the greatest impact on the establishment of nurses' nursing image. Improving the nursing profession's prestige and social position as well as providing the opportunity for creativity and originality in nursing practice will change the self-image of Iranian nurses, facilitating effective and lasting changes in nursing's image. Nurse managers are well-placed to influence nurses' perceptions of nursing's image. Given the finding that thinking about leaving a job positively correlates with holding a negative nursing image, nurse managers need to consider how they can work effectively with their staff to enhance morale and nurses' experience of their job. © 2012 Blackwell Publishing Ltd.

  18. E-commerce factors influencing consumers‘ online shopping decision

    OpenAIRE

    Baubonienė, Živilė; Gulevičiūtė, Gintarė

    2015-01-01

    Purpose – The purpose of this paper is to look at the factors driving online shopping and to develop an understanding of the factors influencing the online shopping by the consumers. This is done by exploring the factors that encourage consumers to shop online through analysis of such advantages as security, fast delivery, comparable price, convenience, cheaper prices and a wider choice. At the same time, the research project reveals the factors that are discouraging for consumers and the ben...

  19. Factors influencing job satisfaction and organizational commitment.

    Science.gov (United States)

    Watson, Liana M

    2008-01-01

    To assess the relationship between intrinsic and extrinsic motivational factors influencing job satisfaction and the perspective of frontline medical imaging staff in acute care health care facilities in the United States. The sample consisted of 359 registered radiologic technologists who were working as staff technologists in acute care health care facilities in the United States. The results of the study suggest that satisfaction with intrinsic and extrinsic motivators influences overall satisfaction with the work environment and job and commitment to the employer.

  20. What Factors Influence Knowledge Sharing in Organizations?

    DEFF Research Database (Denmark)

    Razmerita, Liana; Kirchner, Kathrin; Nielsen, Pia

    2016-01-01

    factors drive employees’ participation and what factors hamper their participation in enterprise social media. Design/methodology/approach: Based on a literature review, a unified research model is derived integrating demographic, individual, organizational and technological factors that influence......Purpose: Enterprise social media platforms provide new ways of sharing knowledge and communicating within organizations to benefit from the social capital and valuable knowledge that employees have. Drawing on social dilemma and self-determination theory, the aim of the study is to understand what...... knowledge sharing framework helps to understand what factors impact engagement on social media. Furthermore the article suggests different types of interventions to overcome the social dilemma of knowledge sharing. Originality/value: The study contributes to an understanding of factors leading...

  1. Factors influencing laser cutting of wood

    Science.gov (United States)

    V.G. Barnekov; C.W. McMillin; H.A. Huber

    1986-01-01

    Factors influencing the ability of lasers to cut wood may be generally classified into these three areas: 1) characteristics of the laser beam; 2) equipment and processing variables; and 3) properties of the workpiece. Effects of beam power, mode, polarization, and stability are discussed as are aspects of optics, location of focal point, feed speed, gas-jet assist...

  2. Review on Factors Influencing Physician Guideline Adherence in Cardiology.

    Science.gov (United States)

    Hoorn, C J G M; Crijns, H J G M; Dierick-van Daele, A T M; Dekker, L R C

    2018-04-09

    Cardiovascular disease is the most common cause of death in Western countries. Physician adherence to guidelines is often suboptimal, resulting in impaired patient outcome and prognosis. Multiple studies have been conducted to evaluate patterns and the influencing factors of patient adherence, but little is known about factors influencing physician guideline adherence. This review aims to identify factors influencing physician guideline adherence relevant to cardiology and to provide insights and suggestions for future improvement. Physician adherence was measured as adherence to standard local medical practice and applicable guidelines. Female gender and older age had a negative effect on physician guideline adherence. In addition, independent of the type of heart disease, physicians without cardiologic specialization were linked to physician noncompliance. Also, guideline adherence in primary care centers was at a lower level compared to secondary or tertiary care centers. The importance of guideline adherence increases as patients age, and complex diseases and comorbidity arise. Appropriate resources and interventions, taking important factors for nonadherence in account, are necessary to improve guideline adoption and adherence in every level of the chain. This in turn should improve patient outcome.

  3. Factors influencing women\\'s decisions to purchase specific children ...

    African Journals Online (AJOL)

    Factors influencing women\\'s decisions to purchase specific children\\'s ... they had selected a children's multi-nutrient supplement with the intention of buying it. ... Price, performance and brand loyalty, affect and normative factors were most ...

  4. Librarians' Perspectives on the Factors Influencing Research Data Management Programs

    Science.gov (United States)

    Faniel, Ixchel M.; Connaway, Lynn Silipigni

    2018-01-01

    This qualitative research study examines librarians' research data management (RDM) experiences, specifically the factors that influence their ability to support researchers' needs. Findings from interviews with 36 academic library professionals in the United States identify 5 factors of influence: (1) technical resources; (2) human resources; (3)…

  5. Factors influencing societal response of nanotechnology: an expert stakeholder analysis

    International Nuclear Information System (INIS)

    Gupta, Nidhi; Fischer, Arnout R. H.; Lans, Ivo A. van der; Frewer, Lynn J.

    2012-01-01

    Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an important role in how nanotechnology is developed and commercialised. This article aims to identify expert opinion on factors influencing societal response to applications of nanotechnology. Structured interviews with experts on nanotechnology from North West Europe were conducted using repertory grid methodology in conjunction with generalized Procrustes analysis to examine the psychological constructs underlying societal uptake of 15 key applications of nanotechnology drawn from different areas (e.g. medicine, agriculture and environment, chemical, food, military, sports, and cosmetics). Based on expert judgement, the main factors influencing societal response to different applications of nanotechnology will be the extent to which applications are perceived to be beneficial, useful, and necessary, and how 'real' and physically close to the end-user these applications are perceived to be by the public.

  6. Factors influencing societal response of nanotechnology: an expert stakeholder analysis

    Science.gov (United States)

    Gupta, Nidhi; Fischer, Arnout R. H.; van der Lans, Ivo A.; Frewer, Lynn J.

    2012-05-01

    Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an important role in how nanotechnology is developed and commercialised. This article aims to identify expert opinion on factors influencing societal response to applications of nanotechnology. Structured interviews with experts on nanotechnology from North West Europe were conducted using repertory grid methodology in conjunction with generalized Procrustes analysis to examine the psychological constructs underlying societal uptake of 15 key applications of nanotechnology drawn from different areas (e.g. medicine, agriculture and environment, chemical, food, military, sports, and cosmetics). Based on expert judgement, the main factors influencing societal response to different applications of nanotechnology will be the extent to which applications are perceived to be beneficial, useful, and necessary, and how 'real' and physically close to the end-user these applications are perceived to be by the public.

  7. Emergency Department Crowding: Factors Influencing Flow

    Directory of Open Access Journals (Sweden)

    Arkun, Alp

    2010-02-01

    Full Text Available Background: The objective of this study was to evaluate those factors, both intrinsic and extrinsic to the emergency department (ED that influence two specific components of throughput: “door-to-doctor” time and dwell time.Methods: We used a prospective observational study design to determine the variables that played a significant role in determining ED flow. All adult patients seen or waiting to be seen in the ED were observed at 8pm (Monday-Friday during a three-month period. Variables measured included daily ED volume, patient acuity, staffing, ED occupancy, daily admissions, ED boarder volume, hospital volume, and intensive care unit volume. Both log-rank tests and time-to-wait (survival proportional-hazard regression models were fitted to determine which variables were most significant in predicting “door-to-doctor” and dwell times, with full account of the censoring for some patients.Results: We captured 1,543 patients during our study period, representing 27% of total daily volume. The ED operated at an average of 85% capacity (61-102% with an average of 27% boarding. Median “door-to-doctor” time was 1.8 hours, with the biggest influence being triage category, day of the week, and ED occupancy. Median dwell time was 5.5 hours with similar variable influences.Conclusion: The largest contributors to decreased patient flow through the ED at our institution were triage category, ED occupancy, and day of the week. Although the statistically significant factors influencing patient throughput at our institution involve problems with inflow, an increase in ED occupancy could be due to substantial outflow obstruction and may indicate the necessity for increased capacity both within the ED and hospital. [West J Emerg Med. 2010; 11(1:10-15

  8. Diagnostics of the Factors Influencing the Export Activity of an Enterprise

    Directory of Open Access Journals (Sweden)

    Skrynkovskyy Ruslan M.

    2017-09-01

    Full Text Available The modern practice of doing business proves that a successful entrance of any enterprise to external (international markets depends on the level of its readiness for carrying out foreign economic activity. Under such circumstances, the process of targeted analysis and assessment of factors influencing the export activity of the enterprise is relevant, expedient and important. The aim of the article is the formation and development of theoretical and methodological bases for diagnosing factors influencing the export activity of an enterprise on the basis of theory and practice in the field of management and administration. It is found that the diagnostics should be understood as the process of identification, analysis and evaluation of influence (functional, dysfunctional of the factors (circumstances, conditions, etc. on the export activity of an enterprise in order to identify and solve problems (current, possible ones in the sphere of supply and implementation of specific actions (steps related to its entrance to external (international markets. It is determined that the key business indicators of the system for diagnosing the factors influencing the export activity of an enterprise are indicators reflecting the influence of the main factors on its export activity: level of fulfillment of obligations in terms of cost; level of conclusion of “expensive contracts”; share of renewed business contracts in the total number of contracts; level of satisfaction of claims; level of delivery variability. The prospect for further research in this scientific direction is developing a system of partial diagnostic goals of the integrated system of goals for conducting economic diagnostics of enterprises taking into account the diagnostics of factors influencing the export activity of an enterprise as a partial diagnostic goal.

  9. Factors Influencing Medical Students' Choice of Specialty

    OpenAIRE

    Chang, Pei-Yeh; Hung, Chih-Young; Wang, Kuei-lng; Huang, Yuan-Huei; Chang, King-Jen

    2006-01-01

    Medical school graduates are the source of a country's physicians. Determining how the graduates of these schools select their areas of specialization is the key to achieving a balanced distribution of doctors among all specialties. The purposes of this study were to determine the factors that influence medical students' choice of medical specialty, and to derive the relative weight of each factor. Methods: We constructed a two-tiered analytic hierarchy process (AHP) model which was repres...

  10. Computer Self-Efficacy and Factors Influencing E-Learning Effectiveness

    Science.gov (United States)

    Chien, Tien-Chen

    2012-01-01

    Purpose: The purpose of this study is to investigate the influences of system and instructor factors on e-learning effectiveness under the interactions of computer self-efficacy. In this study, the factors of the e-learning system are functionality, interaction, and response. The factors of the e-learning instructor are attitude, technical skills,…

  11. Factors influencing woodlands of southwestern North Dakota

    Science.gov (United States)

    Michele M. Girard; Harold Goetz; Ardell J. Bjugstad

    1987-01-01

    Literature pertaining to woodlands of southwestern North Dakota is reviewed. Woodland species composition and distribution, and factors influencing woodland ecosystems such as climate, logging, fire, and grazing are described. Potential management and improvement techniques using vegetation and livestock manipulation have been suggested.

  12. Factors that influence advertising design ideation | Usman ...

    African Journals Online (AJOL)

    Factors that influence advertising design ideation. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... inevitably, more than ever before, on advertisement to take products to the doorsteps of potential consumers. Consequently, local and global corporations employ all manner of advertising media to achieve their end.

  13. ICT Interventions for Girls: Factors Influencing ICT Career Intentions

    Directory of Open Access Journals (Sweden)

    Elena Gorbacheva

    2014-11-01

    Full Text Available Intervention programs aimed at promoting study and work opportunities in the Information and Communications Technology (ICT field to schoolgirls have been encouraged to combat a decline in the interest among girls to study ICT at school. The goal of our study is to investigate the influence of such interventions on schoolgirls’ intentions to choose a career in the ICT field by analysing comprehensive survey data (n = 3577, collected during four interventions in Australia, using the Partial Least Squares method. Our study is also aimed at identifying other factors influencing ICT career intentions. We found that the attitude towards interventions has an indirect influence on ICT career intentions by affecting interest in ICT. Our results also challenge several existing theoretical studies by showing that factors that had previously been suggested as influencers were found to have little or no impact in this study, these being same-sex education and computer usage.

  14. Factors influencing the intention to watch online video advertising.

    Science.gov (United States)

    Lee, Joonghwa; Lee, Mira

    2011-10-01

    This study examines the factors influencing consumer intention to watch online video ads, by applying the theory of reasoned action. The attitude toward watching online video ads, the subjective norm, and prior frequency of watching online video ads positively influence the intention to watch online video ads. Further, beliefs held about entertainment and information outcomes from watching online video ads and subjective norm influence attitude toward watching these ads.

  15. Factors Influencing Professional Help-Seeking for Suicidality.

    Science.gov (United States)

    Han, Jin; Batterham, Philip J; Calear, Alison L; Randall, Rebecca

    2018-05-01

    Evidence suggests that the majority of people with suicidality do not seek help. Little systematic evaluation of factors influencing professional help-seeking has been done. To systematically evaluate the factors that influence professional help-seeking for suicidality. Published quantitative and qualitative studies in Medline and PsycInfo databases were reviewed following PRISMA. In all, 55 relevant studies were identified. Of these, 15 studies examined professional help-seeking intentions for perceived suicidal ideation, among people with or without suicidality; 21 studies examined professional help-seeking behavior among people with suicidality; and 19 studies examined suicidal decedents' health services use. Several potential important barriers were identified including high self-reliance, lack of perceived need for treatment, and stigmatizing attitudes toward suicide, toward mental health issues, and toward seeking professional treatment. The presence of suicidality and mental health issues was found to generally decrease help-seeking intentions for perceived suicidal ideation while facilitating actual service use. Social support and informal support from family and friends also played an important role in professional help-seeking. Although the majority of the included studies were of sound quality, some of the factors identified in the review were assessed in relatively few studies, and most of the included studies were conducted in industrialized countries. Further quantitative and qualitative studies examining the potential important factors in broader community samples, especially in developing countries, are needed.

  16. Factors influencing condom use among Nigerian undergraduates: A ...

    African Journals Online (AJOL)

    Factors influencing condom use among Nigerian undergraduates: A mixed method study. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... group discussions) and quantitative (cross-sectional survey) methods were utilised for this study.

  17. Factors influencing insulin secretion from encapsulated islets

    NARCIS (Netherlands)

    de Haan, BJ; Faas, MM; de Vos, P

    2003-01-01

    Adequate regulation of glucose levels by a microencapsulated pancreatic islet graft requires a minute-to-minute regulation of blood glucose. To design such a transplant, it is mandatory to have sufficient insight in factors influencing the kinetics of insulin secretion by encapsulated islets. The

  18. A real-time assessment of factors influencing medication events.

    Science.gov (United States)

    Dollarhide, Adrian W; Rutledge, Thomas; Weinger, Matthew B; Fisher, Erin Stucky; Jain, Sonia; Wolfson, Tanya; Dresselhaus, Timothy R

    2014-01-01

    Reducing medical error is critical to improving the safety and quality of healthcare. Physician stress, fatigue, and excessive workload are performance-shaping factors (PSFs) that may influence medical events (actual administration errors and near misses), but direct relationships between these factors and patient safety have not been clearly defined. This study assessed the real-time influence of emotional stress, workload, and sleep deprivation on self-reported medication events by physicians in academic hospitals. During an 18-month study period, 185 physician participants working at four university-affiliated teaching hospitals reported medication events using a confidential reporting application on handheld computers. Emotional stress scores, perceived workload, patient case volume, clinical experience, total sleep, and demographic variables were also captured via the handheld computers. Medication event reports (n = 11) were then correlated with these demographic and PSFs. Medication events were associated with 36.1% higher perceived workload (p sleep (p = .10). These results confirm the effect of factors influencing medication events, and support attention to both provider and hospital environmental characteristics for improving patient safety. © 2013 National Association for Healthcare Quality.

  19. Factors influencing the vulnerability of women to the risk of HIV ...

    African Journals Online (AJOL)

    Factors influencing the vulnerability of women to the risk of HIV-infection in rural villages in North West Province, South Africa. ... Gender and Behaviour ... This particular study found that there are a number of personal, proximal and distal factors that influence the vulnerability of women to HIV-infection in rural villages in ...

  20. Factors Influencing the Yemeni Customers’ Intention to Adopt Takaful Products

    Directory of Open Access Journals (Sweden)

    Abdelghani Echchabi

    2015-01-01

    Full Text Available The purpose of this study is to examine the Yemeni customers’ intention to adopt Takaful products, and to explore the potential factors that influence their decision. This study applies SEM and one sample t-test to analyse the collected data. The results indicate that among the factors included in this study, only compatibility positively and significantly affects the adoption intention. This is the first study that addresses the adoption of Takaful products in Yemen and the factors that influence it. Furthermore, this study extends the Innovations Diffusion Theory (IDT by applying it to a different setting.

  1. An empirical survey on factors influencing on packaging dairy products

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2013-07-01

    Full Text Available Packaging plays an essential role on supplying different materials such as dairy products. The first thing people may look into when they purchase dairy products such as milk, cheese, etc. is associated with the packaging characteristics. This paper attempts to find important factors influencing on packaging dairy products. The study uses factor analysis to detect important factors based on a questionnaire consists of 28 questions in Likert scale, which is distributed among 200 regular employees of Pegah dairy producer. Cronbach alpha, Kaiser-Meyer-Olkin Measure of Sampling adequacy and Bartlett's test of Sphericity approximation Chi-Square are 0.81, 0.679 and 844.475, respectively and they are within acceptable limit. The study has determined five factors including infrastructure, awareness, design and communication as important factors influencing consumers.

  2. Pakistani medical students' specialty preference and the influencing factors.

    Science.gov (United States)

    Rehman, Anis; Rehman, Tariq; Shaikh, Muhammad Ateeb; Yasmin, Haleema; Asif, Ammara; Kafil, Hina

    2011-07-01

    To elucidate the specialty preferences of Pakistani medical students and the factors which influence medical students to make the decision regarding which specialty to pursue. Both basic sciences and clinical students from four medical colleges of Pakistan, i.e., Dow Medical College, Sindh Medical College, Liaquat National Medical College and Muhammad Medical College, were included in the cross-sectional survey during the period of July 2008 to Jan' 2009. After ethical acceptance, data was collected using convenient sampling technique. The questionnaire covered the following demographic details: 13 common specialties and 15 influencing factors. Questionnaires included in the analysis were 771. Most students gave preference to surgery and its associated sub-specialties (50.3%) followed by internal medicine (26.8%), paediatrics (23.2%), dermatology (16.7%), gynaecology and obstetrics (16.7%), psychiatry (13.1%), radiology (10.8%), ENT (8.8%), anaesthesiology (8.7%), administrative medicine (8.6%), orthopaedics (8.2%), ophthalmology (7.5%), and laboratory medicine (6.1%). The highly considered factors (regarding specialties) chosen by 70% of the medical students were: applicable to respective personalities of the individuals, prestige and respect, international opportunities, and time commitment. Surgical-skills, job availability, financial rating, academic performance, and a role model were moderately influencing factors. Hospital environment, parents, general practice, peer-pressure and personal health were the least influential. This trend suggests competition in surgery and its sub-specialties along with internal medicine, paediatrics, dermatology, gynaecology and obstetrics. Specialty suited to personality, time commitment, prestige/respect and international opportunity, influenced more than 70% of the students.

  3. An artificial perch to help Snail Kites handle an exotic Apple Snail

    Science.gov (United States)

    Pias, Kyle E.; Welch, Zach C.; Kitchens, Wiley M.

    2012-01-01

    In the United States, the Snail Kite (Rostrhamus sociabilis plumbeus) is a federally endangered species and restricted to the wetlands of south-central Florida where the current population numbers less than 1,500. The Snail Kite is an extreme dietary specialist, previously feeding almost exclusively on one species of snail, the Florida Apple Snail (Pomacea paludosa). Within the past decade, an exotic species of apple snail, the Island Apple Snail (Pomacea insularum), has become established on lakes in central Florida. Island Apple Snails are larger than the native Florida Apple Snails, and Snail Kites handle the exotic snails less efficiently. Juvenile Snail Kites, in particular, have lower daily energy balances while feeding on Island Apple Snails. An inexpensive, easy-to-construct platform was developed that would provide Snail Kites with a flat, stable surface on which to extract snails. The platform has the potential to reduce the difficulties Snail Kites experience when handling exotic snails, and may benefit the Snail Kite population as a whole. Initial observations indicate that Snail Kites use the platforms frequently, and snails extracted at the platforms are larger than snails extracted at other perches.

  4. Factors influencing training transfer in nursing profession: a qualitative study.

    Science.gov (United States)

    Ma, Fang; Bai, Yangjing; Bai, Yangjuan; Ma, Weiguang; Yang, Xiangyu; Li, Jiping

    2018-03-20

    There is a growing recognition that training is not translated into performance and the 'transfer problem' exists in organization training today. Although factors contributing to training transfer have been identified in business and industry, the factors influencing training transfer in nursing profession remain less clear. A qualitative descriptive study was undertaken in two tertiary referral hospitals in China from February 2013 to September 2013. Purposeful sampling of 24 nursing staffs were interviewed about the factors influencing training transfer. Seven themes evolved from the analysis, categorized in 4 main domains, which described the factors influencing training transfer in nursing profession in trainee characteristics, training design, work environment and profession domain. The trainee characteristics domain included attitude and ability. The training design domain included training content and instruction method. The work environment domain included supports as facilitators and opposition as hindrance. The theme pertaining to the profession domain was professional development. Health care managers need to understand the factors influencing training transfer for maximizing the benefits of training. The right beliefs and values about training, the rigorous employee selection for training, the relevance of training content, training instructions facilitating learning and transfer, supports from peer, supervisors and the organization, organizational culture such as change, sharing, learning and support, and professional development are key to successful training transfer. Furthermore, managers should be aware of the opposition from co-workers and find ways to prevent it.

  5. Factors influencing antibiotic prescribing in long-term care facilities: a qualitative in-depth study.

    Science.gov (United States)

    van Buul, Laura W; van der Steen, Jenny T; Doncker, Sarah M M M; Achterberg, Wilco P; Schellevis, François G; Veenhuizen, Ruth B; Hertogh, Cees M P M

    2014-12-16

    Insight into factors that influence antibiotic prescribing is crucial when developing interventions aimed at a more rational use of antibiotics. We examined factors that influence antibiotic prescribing in long-term care facilities, and present a conceptual model that integrates these factors. Semi-structured qualitative interviews were conducted with physicians (n = 13) and nursing staff (n = 13) in five nursing homes and two residential care homes in the central-west region of the Netherlands. An iterative analysis was applied to interviews with physicians to identify and categorize factors that influence antibiotic prescribing, and to integrate these into a conceptual model. This conceptual model was triangulated with the perspectives of nursing staff. The analysis resulted in the identification of six categories of factors that can influence the antibiotic prescribing decision: the clinical situation, advance care plans, utilization of diagnostic resources, physicians' perceived risks, influence of others, and influence of the environment. Each category comprises several factors that may influence the decision to prescribe or not prescribe antibiotics directly (e.g. pressure of patients' family leading to antibiotic prescribing) or indirectly via influence on other factors (e.g. unfamiliarity with patients resulting in a higher physician perceived risk of non-treatment, in turn resulting in a higher tendency to prescribe antibiotics). Our interview study shows that several non-rational factors may affect antibiotic prescribing decision making in long-term care facilities, suggesting opportunities to reduce inappropriate antibiotic use. We developed a conceptual model that integrates the identified categories of influencing factors and shows the relationships between those categories. This model may be used as a practical tool in long-term care facilities to identify local factors potentially leading to inappropriate prescribing, and to subsequently

  6. Factors influencing the adoption of mobile financial services in the ...

    African Journals Online (AJOL)

    Factors influencing the adoption of mobile financial services in the unbanked population. ... Inkanyiso: Journal of Humanities and Social Sciences ... the influences of the adoption behaviour at different level of market maturity and points of time.

  7. Genetic and environmental factors influencing the Placental Growth Factor (PGF variation in two populations.

    Directory of Open Access Journals (Sweden)

    Rossella Sorice

    Full Text Available Placental Growth Factor (PGF is a key molecule in angiogenesis. Several studies have revealed an important role of PGF primarily in pathological conditions (e.g.: ischaemia, tumour formation, cardiovascular diseases and inflammatory processes suggesting its use as a potential therapeutic agent. However, to date, no information is available regarding the genetics of PGF variability. Furthermore, even though the effect of environmental factors (e.g.: cigarette smoking on angiogenesis has been explored, no data on the influence of these factors on PGF levels have been reported so far. Here we have first investigated PGF variability in two cohorts focusing on non-genetic risk factors: a study sample from two isolated villages in the Cilento region, South Italy (N=871 and a replication sample from the general Danish population (N=1,812. A significant difference in PGF mean levels was found between the two cohorts. However, in both samples, we observed a strong correlation of PGF levels with ageing and sex, men displaying PGF levels significantly higher than women. Interestingly, smoking was also found to influence the trait in the two populations, although differently. We have then focused on genetic risk factors. The association between five single nucleotide polymorphisms (SNPs located in the PGF gene and the plasma levels of the protein was investigated. Two polymorphisms (rs11850328 and rs2268614 were associated with the PGF plasma levels in the Cilento sample and these associations were strongly replicated in the Danish sample. These results, for the first time, support the hypothesis of the presence of genetic and environmental factors influencing PGF plasma variability.

  8. Impact of two telemetry transmitter implantation incision suturing methods on the physiological state and condition of perch (Perca fluviatilis

    Directory of Open Access Journals (Sweden)

    Rożyński Maciej

    2017-06-01

    Full Text Available The aim of this work was to determine the impact on European perch, Perca fluviatilis L. (mean body weight – 78.33 g of the intraperitoneal implantation of telemetry transmitters using different suturing methods. In the first experiment silk sutures were used (experiment I – group ST, while in the second tissue adhesive was used (experiment II – group GT. Following the procedure, the fish were kept for 42 days in a recirculating system. Differences in growth and condition parameters were only noted in the first week of the experiment. Specimens from group GT had lower values for DGR (daily growth rate and SGR (specific growth rate, but a higher value for FCR (feed conversion ratio values. For the hematological parameters, lower values of MCV (mean corpuscular volume and PLT (blood platelets were noted in group GT, while for the biochemical parameters, lowered ALP (alkaline phosphatase activity and Mg (magnesium concentrations were noted in group ST. In group ST, 33.3% of the specimens loss their tags, while in group GT 77.8% did so. Differences in incision healing were only noted in the second week, when specimens in group ST were observed to have fully closed incisions, while in group GT 50% of the incisions were open. Despite the high percentage of implantation incision healing in both groups, because of the high values of tag loss rate, neither method can be recommended for perch. It might be more effective to use tag with external antennae in this species. The method use for closing implantation incisions also must be improved to eliminate tag shedding.

  9. 471 socio-economic factors influencing agricultural radio

    African Journals Online (AJOL)

    Osondu

    The study examined socio economic factors influencing agricultural radio programme FILIN. MAINOMA in ... statistics such as, Pearson Product Moment Correlation Coefficient (PPMC) and Chi-Square analysis. (χ. 2). .... of fish farmers association while one third. (22.22%) ... problems of language barrier and 6.00% of the.

  10. Consequences of Hatch Phenology on Stages of Fish Recruitment.

    Directory of Open Access Journals (Sweden)

    David M Bogner

    Full Text Available Little is known about how hatch phenology (e.g., the start, peak, and duration of hatching could influence subsequent recruitment of freshwater fishes into a population. We used two commonly sympatric fish species that exhibit different hatching phenologies to examine recruitment across multiple life stages. Nine yellow perch (Perca flavescens and bluegill (Lepomis macrochirus annual cohorts were sampled from 2004 through 2013 across larval, age-0, age-1, and age-2 life stages in a Nebraska (U.S.A. Sandhill lake. Yellow perch hatched earlier in the season and displayed a more truncated hatch duration compared to bluegill. The timing of hatch influenced recruitment dynamics for both species but important hatching metrics were not similar between species across life stages. A longer hatch duration resulted in greater larval yellow perch abundance but greater age-1 bluegill abundance. In contrast, bluegill larval and age-0 abundances were greater during years when hatching duration was shorter and commenced earlier, whereas age-0 yellow perch abundance was greater when hatching occurred earlier. As a result of hatch phenology, yellow perch recruitment variability was minimized sooner (age-0 life stage than bluegill (age-1 life stage. Collectively, hatch phenology influenced recruitment dynamics across multiple life stages but was unique for each species. Understanding the complexities of when progeny enter an environment and how this influences eventual recruitment into a population will be critical in the face of ongoing climate change.

  11. Investigating different factors influencing on brand equity

    Directory of Open Access Journals (Sweden)

    Afsane Zamanimoghadam

    2014-07-01

    Full Text Available The purpose of this paper is to determine and prioritize factors influencing on brand equity in consumer’s point of view for a case study of Samsung appliance consumers in city of Tehran, Iran. The study investigates the effects of four factors in terms of the customer's perspective, price, advertisement, family and brand image, by dimensions of brand equity, perceived quality, brand awareness, brand association, brand loyalty, on brand equity. The research method is based on a descriptive-survey research. The questionnaire includes Samsung consumers in city of Tehran, Iran. To test the hypotheses, SPSS and LISREL software packages are used. For data analysis, descriptive statistics and inferential statistical tests including structural equation modeling and path analysis are used. The results of the survey have indicated that family and brand image influence positively on brand equity but the effects of advertisement and price on brand equity were not confirmed.

  12. Factors that influence women's dispositions toward science

    Science.gov (United States)

    Atria, Catherine Graczyk

    Females have been underrepresented in the study of science and science careers for decades although advancements have been made in closing this gender gap, the gap persists particularly in the physical sciences. Variables which influence a woman's desire to pursue and maintain a science course of study and career must be discovered. The United States lags behind other industrialized countries in the fields of science, math, and engineering. Females comprise an estimated half of the population; their potential contributions cannot be ignored or overlooked. This retrospective research study explores the personal experiences of ten women enrolled in science majors, with science related career plans. The goal of this study is to describe the factors that influence the participants' interest in science. The findings, the effect of science coursework, science teachers' personality and manner, other influential educational personnel, role models and mentors, external influences exclusive of school, parental influence, locus of control and positive attitudes toward science confirm what other researchers have found.

  13. Analysis on influencing factors of clinical teachers’ job satisfaction by structural equation model

    Directory of Open Access Journals (Sweden)

    Haiyi Jia

    2017-02-01

    Full Text Available [Research objective] Analyze the influencing factors of clinical teachers’ job satisfaction. [Research method] The ERG theory was used as the framework to design the questionnaires. Data were analyzed by structural equation model for investigating the influencing factors. [Research result] The modified model shows that factors of existence needs and growth needs have direct influence on the job satisfaction of clinical teachers, the influence coefficients are 0.540 and 0.380. The three influencing factors have positive effects on each other, and the correlation coefficients are 0.620, 0.400 and 0.330 respectively. [Research conclusion] Relevant departments should take active measures to improve job satisfaction of clinical teachers from two aspects: existence needs and growth needs, and to improve their work enthusiasm and teaching quality.

  14. Factors influencing societal response of nanotechnology: an expert stakeholder analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Nidhi, E-mail: nidhi.gupta@wur.nl; Fischer, Arnout R. H., E-mail: arnout.fischer@wur.nl; Lans, Ivo A. van der, E-mail: Ivo.vanderLans@wur.nl [Wageningen University, Marketing and Consumer Behaviour Group (Netherlands); Frewer, Lynn J., E-mail: lynn.frewer@newcastle.ac.uk [Newcastle University, School of Agriculture, Food and Rural Development (United Kingdom)

    2012-05-15

    Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an important role in how nanotechnology is developed and commercialised. This article aims to identify expert opinion on factors influencing societal response to applications of nanotechnology. Structured interviews with experts on nanotechnology from North West Europe were conducted using repertory grid methodology in conjunction with generalized Procrustes analysis to examine the psychological constructs underlying societal uptake of 15 key applications of nanotechnology drawn from different areas (e.g. medicine, agriculture and environment, chemical, food, military, sports, and cosmetics). Based on expert judgement, the main factors influencing societal response to different applications of nanotechnology will be the extent to which applications are perceived to be beneficial, useful, and necessary, and how 'real' and physically close to the end-user these applications are perceived to be by the public.

  15. Factors influencing post-traumatic stress in Korean forensic science investigators.

    Science.gov (United States)

    Yoo, Yang-Sook; Cho, Ok-Hee; Cha, Kyeong-Sook; Boo, Yun-Jeong

    2013-09-01

    The aim of this study was to understand factors that influence post-traumatic stress (PTS) in Korean forensic science investigators. A total of 111 forensic science investigators were recruited in Korea. PTS was measured using the tool modified by Choi (2001) from the original developed by Foa, Riggs, Dancu, and Rothbaum (1993) based on DSM-IV. Factors influencing PTS included demographic and job-related characteristics, emotional intelligence, and death anxiety. PTS scores were positively correlated with personality type, fatigue from work, and death anxiety. PTS scores were negatively correlated with length of career as a forensic science investigator and emotional intelligence. The factors that had the greatest influence on PTS were death anxiety, years spent as a forensic science investigator, personality type, emotional intelligence, fatigue, and homicide experience. The explanatory power of these six factors was 44.0%. Therefore, it is necessary to regularly evaluate the mental health of those who are vulnerable to PTS. Based on these results, various interventions could be implemented for promoting overall health of the forensic science investigators. Copyright © 2013. Published by Elsevier B.V.

  16. The influence of the trawl mouth opening size and net colour on catch efficiency during sampling of early fish stages

    Czech Academy of Sciences Publication Activity Database

    Jůza, T.; Čech, Martin; Kubečka, Jan; Vašek, Mojmír; Peterka, Jiří; Matěna, Josef

    2010-01-01

    Roč. 105, č. 3 (2010), s. 125-133 ISSN 0165-7836 R&D Projects: GA ČR(CZ) GP206/09/P266; GA AV ČR(CZ) 1QS600170504 Institutional research plan: CEZ:AV0Z60170517 Keywords : trawl efficiency * fry density * perch Subject RIV: EH - Ecology, Behaviour Impact factor: 1.656, year: 2010

  17. Factors Potentially Influencing Student Acceptance of Biological Evolution

    Science.gov (United States)

    Wiles, Jason R.

    This investigation explored scientific, religious, and otherwise nonscientific factors that may influence student acceptance of biological evolution and related concepts, how students perceived these factors to have influenced their levels of acceptance of evolution and changes therein, and what patterns arose among students' articulations of how their levels of acceptance of evolution may have changed. This exploration also measured the extent to which students' levels of acceptance changed following a treatment designed to address factors identified as potentially affecting student acceptance of evolution. Acceptance of evolution was measured using the MATE instrument (Rutledge and Warden, 1999; Rutledge and Sadler, 2007) among participants enrolled in a secondary-level academic program during the summer prior to their final year of high school and as they transitioned to the post-secondary level. Student acceptance of evolution was measured to be significantly higher than pre-treatment levels both immediately following and slightly over one year after treatment. Qualitative data from informal questionnaires, from formal course evaluations, and from semi-structured interviews of students engaged in secondary level education and former students at various stages of post-secondary education confirmed that the suspected factors were perceived by participants to have influenced their levels of acceptance of evolution. Furthermore, participant reports provided insight regarding the relative effects they perceived these factors to have had on their evolution acceptance levels. Additionally, many participants reported that their science teachers in public schools had avoided, omitted, or denigrated evolution during instruction, and several of these students expressed frustration regarding what they perceived to have been a lack of education of an important scientific principle. Finally, no students expressed feelings of being offended by having been taught about

  18. Why neurology? Factors which influence career choice in neurology.

    Science.gov (United States)

    Albert, Dara V; Hoyle, Chad; Yin, Han; McCoyd, Matthew; Lukas, Rimas V

    2016-01-01

    To evaluate the factors which influence the decision to pursue a career in neurology. An anonymous survey was developed using a Likert scale to rate responses. The survey was sent to adult and child neurology faculty, residents and fellows, as well as medical students applying for neurology. Descriptive statistics were used to analyse the factors of influence. Respondents were subsequently categorized into pre-neurology trainees, neurology trainees, child neurologists and adult neurologists, and differences between the groups were analysed using Pearson's chi-square test. One hundred and thirty-three anonymous responses were received. The respondents were neurologists across all levels of training and practice. Across all respondents, the most common factor of high importance was intellectual content of specialty, challenging diagnostic problems, type of patient encountered and interest in helping people. Responses were similar across the groups; however, the earliest trainees cited interest in helping people as most important, while those in neurology training and beyond cite intellectual content of the specialty as most important. As trainees transition from their earliest levels of clinical experience into working as residents and faculty, there is a shift in the cited important factors. Lifestyle and financial factors seem to be the least motivating across all groups. Encouragement from peers, mentors, faculty and practicing physicians is considered high influences in a smaller number of neurologists. This may present an opportunity for practicing neurologists to make connections with medical students early in their education in an effort to encourage and mentor candidates.

  19. Social Cultural Factors Influencing Women's Participation in Sports ...

    African Journals Online (AJOL)

    Social Cultural Factors Influencing Women's Participation in Sports as Perceived by Female Students of the University of Ilorin. ... sports competition while mass media should organize enlightenment programmes that will mitigate the ...

  20. Factors influencing the usage of different types of malaria prevention ...

    African Journals Online (AJOL)

    Objective: To examine factors which influence the use of different types of malaria prevention ... risk areas, religion, education and income influenced ITN usage, whereas only age, malaria .... the uptake of IPTp given that the person would not.

  1. Consumer's Online Shopping Influence Factors and Decision-Making Model

    Science.gov (United States)

    Yan, Xiangbin; Dai, Shiliang

    Previous research on online consumer behavior has mostly been confined to the perceived risk which is used to explain those barriers for purchasing online. However, perceived benefit is another important factor which influences consumers’ decision when shopping online. As a result, an integrated consumer online shopping decision-making model is developed which contains three elements—Consumer, Product, and Web Site. This model proposed relative factors which influence the consumers’ intention during the online shopping progress, and divided them into two different dimensions—mentally level and material level. We tested those factors with surveys, from both online volunteers and offline paper surveys with more than 200 samples. With the help of SEM, the experimental results show that the proposed model and method can be used to analyze consumer’s online shopping decision-making process effectively.

  2. [Analysis of influencing factors of snow hyperspectral polarized reflections].

    Science.gov (United States)

    Sun, Zhong-Qiu; Zhao, Yun-Sheng; Yan, Guo-Qian; Ning, Yan-Ling; Zhong, Gui-Xin

    2010-02-01

    Due to the need of snow monitoring and the impact of the global change on the snow, on the basis of the traditional research on snow, starting from the perspective of multi-angle polarized reflectance, we analyzed the influencing factors of snow from the incidence zenith angles, the detection zenith angles, the detection azimuth angles, polarized angles, the density of snow, the degree of pollution, and the background of the undersurface. It was found that these factors affected the spectral reflectance values of the snow, and the effect of some factors on the polarization hyperspectral reflectance observation is more evident than in the vertical observation. Among these influencing factors, the pollution of snow leads to an obvious change in the snow reflectance spectrum curve, while other factors have little effect on the shape of the snow reflectance spectrum curve and mainly impact the reflection ratio of the snow. Snow reflectance polarization information has not only important theoretical significance, but also wide application prospect, and provides new ideas and methods for the quantitative research on snow using the remote sensing technology.

  3. Factors influencing the flavour of game meat: A review.

    Science.gov (United States)

    Neethling, J; Hoffman, L C; Muller, M

    2016-03-01

    Flavour is a very important attribute contributing to the sensory quality of meat and meat products. Although the sensory quality of meat includes orthonasal and retronasal aroma, taste, as well as appearance, juiciness and other textural attributes, the focus of this review is primarily on flavour. The influence of species, age, gender, muscle anatomical location, diet, harvesting conditions, ageing of meat, packaging and storage, as well as cooking method on the flavour of game meat are discussed. Very little research is available on the factors influencing the flavour of the meat derived from wild and free-living game species. The aim of this literature review is thus to discuss the key ante- and post-mortem factors that influence the flavour of game meat, with specific focus on wild and free-living South African game species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Factors Influencing Renewable Energy Production & Supply - A Global Analysis

    Science.gov (United States)

    Ali, Anika; Saqlawi, Juman Al

    2016-04-01

    Renewable energy is one of the key technologies through which the energy needs of the future can be met in a sustainable and carbon-neutral manner. Increasing the share of renewable energy in the total energy mix of each country is therefore a critical need. While different countries have approached this in different ways, there are some common aspects which influence the pace and effectiveness of renewable energy incorporation. This presentation looks at data and information from 34 selected countries, analyses the patterns, compares the different parameters and identifies the common factors which positively influence renewable energy incorporation. The most successful countries are analysed for their renewable energy performance against their GDP, policy/regulatory initiatives in the field of renewables, landmass, climatic conditions and population to identify the most influencing factors to bring about positive change in renewable energy share.

  5. The Influence Factors and Mechanism of Societal Risk Perception

    Science.gov (United States)

    Zheng, Rui; Shi, Kan; Li, Shu

    Risk perception is one of important subjects in management psychology and cognitive psychology. It is of great value in the theory and practice to investigate the societal hazards that the public cares a lot especially in Socio-economic transition period. A survey including 30 hazards and 6 risk attributes was designed and distributed to about 2, 485 residents of 8 districts, Beijing. The major findings are listed as following: Firstly, a scale of societal risk perception was designed and 2 factors were identified (Dread Risk & Unknown Risk). Secondly, structural equation model was used to analyze the influence factors and mechanism of societal risk perception. Risk preference, government support and social justice could influence societal risk perception directly. Government support fully moderated the relationship between government trust and societal risk perception. Societal risk perception influenced life satisfaction, public policy preferences and social development belief.

  6. Factors influencing HIV seroprevalence rate among pregnant ...

    African Journals Online (AJOL)

    Human immune deficiency virus (HIV) seroprevalence among pregnant women in Calabar was studied. The aims were to establish HIV seroprevalence rate and to identify factors which influence this rate in our pregnant women. HIV seroprevalence rate of 2.7% among antenatal women in Calabar was recorded with a ...

  7. Factors Influencing Examination Malpractice in Secondary Schools ...

    African Journals Online (AJOL)

    The main purpose of this study was to investigate factors influencing examination malpractice in some selected secondary schools in Cross River State, Nigeria. A sample of one thousand two hundred (1200) students were selected across the three educational zones of Ogoja, Ikom and Calabar using stratified, random ...

  8. Factors Influencing Smallholder Farmers Participation in IFAD ...

    African Journals Online (AJOL)

    USER

    2015-02-02

    Feb 2, 2015 ... This study assessed Factors Influencing smallholder farmers' ... percent of the population engaged in agricultural activities as a career and ... that the major source of income of the poor is agriculture and ... shown that farmers have different reasons for participation in agricultural ... 30 Dan gamau 534. 30.

  9. Exploring Factors That Influence Quality Literature Circles

    Science.gov (United States)

    Young, Chase; Mohr, Kathleen A. J.

    2018-01-01

    Research indicates that literature circles are an authentic means for literacy development that students typically enjoy. To better understand the potential value and to add to the research base regarding literature circles, this study, involving 17 fourth graders, explores factors that may influence the quality of literature discussions,…

  10. Socio-economic factors influencing cassava production in Kuje and ...

    African Journals Online (AJOL)

    This study examined socio-economic factors influencing output level of cassava production in Kuje and Abaji Area Councils of Federal Capital Territory, Abuja. The specific objectives were to:identify the socio-economic characteristics of sampled cassava farmers in the study area; determine the socio-economic factors ...

  11. Physico-chemical and biotic factors influencing microalgal seed ...

    African Journals Online (AJOL)

    Physico-chemical and biotic factors influencing microalgal seed culture propagation for inoculation of a ... African Journal of Biotechnology ... used to inoculate an open raceway pond for large scale biomass production for biodiesel production.

  12. Factors influencing global antiretroviral procurement prices.

    Science.gov (United States)

    Wirtz, Veronika J; Forsythe, Steven; Valencia-Mendoza, Atanacio; Bautista-Arredondo, Sergio

    2009-11-18

    Antiretroviral medicines (ARVs) are one of the most costly parts of HIV/AIDS treatment. Many countries are struggling to provide universal access to ARVs for all people living with HIV and AIDS. Although substantial price reductions of ARVs have occurred, especially between 2002 and 2008, achieving sustainable access for the next several decades remains a major challenge for most low- and middle-income countries. The objectives of the present study were twofold: first, to analyze global ARV prices between 2005 and 2008 and associated factors, particularly procurement methods and key donor policies on ARV procurement efficiency; second, to discuss the options of procurement processes and policies that should be considered when implementing or reforming access to ARV programs. An ARV-medicines price-analysis was carried out using the Global Price Reporting Mechanism from the World Health Organization. For a selection of 12 ARVs, global median prices and price variation were calculated. Linear regression models for each ARV were used to identify factors that were associated with lower procurement prices. Logistic regression models were used to identify the characteristics of those countries which procure below the highest and lowest direct manufactured costs. Three key factors appear to have an influence on a country's ARV prices: (a) whether the product is generic or not; (b) the socioeconomic status of the country; (c) whether the country is a member of the Clinton HIV/AIDS Initiative. Factors which did not influence procurement below the highest direct manufactured costs were HIV prevalence, procurement volume, whether the country belongs to the least developed countries or a focus country of the United States President's Emergency Plan For AIDS Relief. One of the principal mechanisms that can help to lower prices for ARV over the next several decades is increasing procurement efficiency. Benchmarking prices could be one useful tool to achieve this.

  13. Influencing factors on the visibility of surface distresses

    Science.gov (United States)

    Smęt, Wojciech; Skakuj, Marek

    2018-05-01

    A systematic and future-oriented maintenance management requires quality-assured data regarding the condition of the roadway. An important characteristic for assessing the condition of the road surface are cracks [1]. Experience has proven that the road surface temperature and residual humidity can influence the visibility of cracks. To investigate and quantify these influencing factors in more detail, the Federal Ministry of Transport and Digital Infrastructure has implemented a comprehensive research project [2], during which several measurement campaigns were carried out at different seasons and at different temperatures and humidity degrees of the road surface. The visibility of the cracks was assessed using the German approach ZTV ZEB-StB [3]. After evaluating the cracks, the data was synchronized and the network allocation of the geo-referenced raw data was realized. The relevant condition performance indicators were calculated subsequently. For each evaluation section of 100 meters length, the mean road surface temperature was calculated and, if available, the type and year of construction of the surface course was determined. The evaluated data was visualized to establish correlations between the data and the influencing factors. For the statistical analysis of the results, a total of six comparative scenarios were defined in which the influencing factors of road surface temperature and residual humidity were assessed. This paper documents the results of the research project. In order to obtain a uniform and comparable picture of the condition of the road surface over the years and thus to be able to observe the aging process of the road surface, the measurement campaigns are to be carried out under defined conditions. The research project included proposals for defining and further specifying the measurement conditions.

  14. Influence of atmospheric factors on the rheumatic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Latman, N S

    1987-01-01

    This paper reviews the influence of atmospheric factors on rheumatic diseases - rheumatoid arthritis, unspecified arthritis, gout, and systemic lupus erythematosis (SLE). The authors state that there appears to be ample evidence to conclude that various atmospheric factors do exert a significant impact on some people with various rheumatic diseases. The data are, however, crude relative to the authors general understanding. They recommend as a logical progression of research the determination of the effects of the meteorological/atmospheric factors of concern on the specific intrinsic mediators of inflammation.

  15. Attitudes, norms and controls influencing lifestyle risk factor management in general practice

    Directory of Open Access Journals (Sweden)

    McKenzie Suzanne H

    2009-08-01

    Full Text Available Abstract Background With increasing rates of chronic disease associated with lifestyle behavioural risk factors, there is urgent need for intervention strategies in primary health care. Currently there is a gap in the knowledge of factors that influence the delivery of preventive strategies by General Practitioners (GPs around interventions for smoking, nutrition, alcohol consumption and physical activity (SNAP. This qualitative study explores the delivery of lifestyle behavioural risk factor screening and management by GPs within a 45–49 year old health check consultation. The aims of this research are to identify the influences affecting GPs' choosing to screen and choosing to manage SNAP lifestyle risk factors, as well as identify influences on screening and management when multiple SNAP factors exist. Methods A total of 29 audio-taped interviews were conducted with 15 GPs and one practice nurse over two stages. Transcripts from the interviews were thematically analysed, and a model of influencing factors on preventive care behaviour was developed using the Theory of Planned Behaviour as a structural framework. Results GPs felt that assessing smoking status was straightforward, however some found assessing alcohol intake only possible during a formal health check. Diet and physical activity were often inferred from appearance, only being assessed if the patient was overweight. The frequency and thoroughness of assessment were influenced by the GPs' personal interests and perceived congruence with their role, the level of risk to the patient, the capacity of the practice and availability of time. All GPs considered advising and educating patients part of their professional responsibility. However their attempts to motivate patients were influenced by perceptions of their own effectiveness, with smoking causing the most frustration. Active follow-up and referral of patients appeared to depend on the GPs' orientation to preventive care, the

  16. Attitudes, norms and controls influencing lifestyle risk factor management in general practice.

    Science.gov (United States)

    Ampt, Amanda J; Amoroso, Cheryl; Harris, Mark F; McKenzie, Suzanne H; Rose, Vanessa K; Taggart, Jane R

    2009-08-26

    With increasing rates of chronic disease associated with lifestyle behavioural risk factors, there is urgent need for intervention strategies in primary health care. Currently there is a gap in the knowledge of factors that influence the delivery of preventive strategies by General Practitioners (GPs) around interventions for smoking, nutrition, alcohol consumption and physical activity (SNAP). This qualitative study explores the delivery of lifestyle behavioural risk factor screening and management by GPs within a 45-49 year old health check consultation. The aims of this research are to identify the influences affecting GPs' choosing to screen and choosing to manage SNAP lifestyle risk factors, as well as identify influences on screening and management when multiple SNAP factors exist. A total of 29 audio-taped interviews were conducted with 15 GPs and one practice nurse over two stages. Transcripts from the interviews were thematically analysed, and a model of influencing factors on preventive care behaviour was developed using the Theory of Planned Behaviour as a structural framework. GPs felt that assessing smoking status was straightforward, however some found assessing alcohol intake only possible during a formal health check. Diet and physical activity were often inferred from appearance, only being assessed if the patient was overweight. The frequency and thoroughness of assessment were influenced by the GPs' personal interests and perceived congruence with their role, the level of risk to the patient, the capacity of the practice and availability of time. All GPs considered advising and educating patients part of their professional responsibility. However their attempts to motivate patients were influenced by perceptions of their own effectiveness, with smoking causing the most frustration. Active follow-up and referral of patients appeared to depend on the GPs' orientation to preventive care, the patient's motivation, and cost and accessibility of

  17. Motivational factors influencing nurses to undertake postgraduate hospital-based education.

    Science.gov (United States)

    Kinsella, Danny; Fry, Margaret; Zecchin, Alison

    2018-05-01

    Specialist postgraduate education improves patient health outcomes, and assists in meeting the emerging specialisation of nursing practice. The aim of this study was to investigate the motivational factors that influence nurses' engagement with hospital-based postgraduate education. The research design was descriptive and exploratory, using a survey method. The survey consisted of demographic details, the Participation Reasons Scale (PRS) and open-ended questions. Thirty-four participants (100%) completed the survey. Of the PRS extrinsic and intrinsic factors, Professional Improvement and Development (Factor 1) and Professional Service (Factor 2), both intrinsic factors, ranked the highest. Therefore, this study identified that intrinsic motivation factors influenced engagement with postgraduate specialty programs for early career nurses. These results highlight the importance of intrinsic motivation factors for a nursing workforce and how this can potentially drive behaviour and decision making. A better understanding of motivation factors across a nurse's career could lead to educational strategies that optimise postgraduate program engagement to better support healthcare delivery and a culture of lifelong learning. Copyright © 2018. Published by Elsevier Ltd.

  18. Impact of Salinity on the Incubation Rate and the Performance during the Nursery Phase of Square Head Climbing Perch (Anabas testudineus Bloch, 1792

    Directory of Open Access Journals (Sweden)

    Le, DV.

    2016-01-01

    Full Text Available Square head climbing perch (Anabas testudineus Bloch, 1792 is a high quality fish without small bones. It grows in a wide range of temperatures (10-42 oC, pH (3.5-9.5 and salinity (up to 16%. As regards climate change, this species may become important for aquaculture in the Tam Giang-Cau Hai lagoon near Hue city. To optimise the quality of fingerlings, we analyzed the effect of salinity levels on hatching and nursing in three subsequent experiments. Fertilization, hatching, survival and growth rates for 30 days were determined at salinity levels 0%, 5%, 7%, 13% and 15%. Water temperature and pH varied between 22-29.5 oC and 7.3-7.8, respectively. Between 0-5%, fertilization ratio was 77% to 83% and highest at 5%, but this dropped to 0% when salinity increased; hatching ratio was larger than 90%, but decreased to 0% at 13-15%. Between 0-11%, hatching time of fertilized eggs was not affected by salinity levels. The ratio of deformation gradually increased above 5%. After hatching at either 0 or 5%, survival ratios for square head climbing perch were above 13% up to 5%, but dropped to 0% at 9%. The growth after 30 days of nursing was higher at 5 and 7% compared with that of 0 and 3%.

  19. Factors influencing cancer treatment decision-making by indigenous peoples: a systematic review.

    Science.gov (United States)

    Tranberg, Rona; Alexander, Susan; Hatcher, Deborah; Mackey, Sandra; Shahid, Shaouli; Holden, Lynda; Kwok, Cannas

    2016-02-01

    We aim to systematically review studies that identify factors influencing cancer treatment decision-making among indigenous peoples. Following the outline suggested by the Preferred Reporting Items for Systematic Review and Meta-analysis, a rigorous systematic review and meta-synthesis were conducted of factors that influence cancer treatment decision-making by indigenous peoples. A total of 733 articles were retrieved from eight databases and a manual search. After screening the titles and abstracts, the full text of 26 articles were critically appraised, resulting in five articles that met inclusion criteria for the review. Because the five articles to be reviewed were qualitative studies, the Critical Appraisal Skills Program toolkit was used to evaluate the methodological quality. A thematic synthesis was employed to identify common themes across the studies. Multiple socio-economic and cultural factors were identified that all had the potential to influence cancer treatment decision-making by indigenous people. These factors were distilled into four themes: spiritual beliefs, cultural influences, communication and existing healthcare systems and structures. Although existing research identified multiple factors influencing decision-making, this review identified that quality studies in this domain are scarce. There is scope for further investigation, both into decision-making factors and into the subsequent design of culturally appropriate programmes and services that meet the needs of indigenous peoples. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Factors influencing early stage healthcare-academia partnerships.

    Science.gov (United States)

    Uvhagen, Håkan; von Knorring, Mia; Hasson, Henna; Øvretveit, John; Hansson, Johan

    2018-02-12

    Purpose The purpose of this paper is to explore factors influencing early implementation and intermediate outcomes of a healthcare-academia partnership in a primary healthcare setting. Design/methodology/approach The Academic Primary Healthcare Network (APHN) initiative was launched in 2011 in Stockholm County, Sweden and included 201 primary healthcare centres. Semi-structured interviews were conducted in 2013-2014 with all coordinating managers ( n=8) and coordinators ( n=4). A strategic change model framework was used to collect and analyse data. Findings Several factors were identified to aid early implementation: assignment and guidelines that allowed flexibility; supportive management; dedicated staff; facilities that enabled APHN actions to be integrated into healthcare practice; and positive experiences from research and educational activities. Implementation was hindered by: discrepancies between objectives and resources; underspecified guidelines that trigger passivity; limited research and educational activities; a conflicting non-supportive reimbursement system; limited planning; and organisational fragmentation. Intermediate outcomes revealed that various actions, informed by the APHN assignment, were launched in all APHNs. Practical implications The findings can be rendered applicable by preparing stakeholders in healthcare services to optimise early implementation of healthcare-academia partnerships. Originality/value This study increases understanding of interactions between factors that influence early stage partnerships between healthcare services and academia in primary healthcare settings.

  1. Factors influencing laser cutting of wood

    Energy Technology Data Exchange (ETDEWEB)

    Barnekov, V. G.; McMillin, C. W.; Huber, H. A.

    1986-07-01

    Factors influencing the ability of lasers to cut wood may be generally classified into these three areas: 1) characteristics of the laser beam; 2) equipment and processing variables; and 3) properties of the work piece. Effects of beam power, mode, polarization, and stability are discussed as are aspects of optics, location of focal point, feed speed, gas-jet assist system and work piece thickness, density, and moisture content. (author)

  2. Important factors influencing the return to work after stroke.

    Science.gov (United States)

    Wang, Ying-Chih; Kapellusch, Jay; Garg, Arun

    2014-01-01

    As the field of rehabilitation shifts its focus towards improving functional capacity instead of managing disability, return to work (RTW) and return to the community emerge as key goals in a person's recovery from major disabling illness such as stroke. To compile important factors believed to influence RTW after a stroke. Based on a comprehensive literature review, we clustered similar factors and organized these factors based on the International Classification of Function, Disability and Health (ICF) framework: body functions or structure, activity participation, environmental factors and personal and psychosocial factors. Overall, stroke severity, as assessed by the degree of residual disability such as weakness, neurological deficit or impairments (speech, cognition, apraxia, agnosia), has been shown to be the most consistent negative predictor of RTW. Many factors such as the number of working years remaining until retirement, depression, medical history, and occupation need to be taken into consideration for stroke survivors, as they can influence RTW decision making. Stroke survivors who are flexible and realistic in their vocational goal and emotionally accept their disability appear more likely to return to work. There are many barriers to employment for stroke survivors ranging from physical and cognitive impairments to psychosocial and environmental factors.

  3. Investigating important factors influencing purchasing from chains

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2012-04-01

    Full Text Available In this paper, we survey important factors, influencing customers to buy more from one of well known food market operating in capital city of Iran named Shahrvand. The survey studies the effects of six factors including customer's perception, persuasive factors, brand, customers' expectations, product's characteristics and special features of store on attracting more customers. We have distributed questionnaire among 196 customers who regularly visit stores and analyzed details of the data. The results indicate that customers' perception is the most important item, which includes eight components. Years of experience is the most important item in our survey followed by impact of color and working hours. Diversity of services is another factor, which plays the most important role followed by quality of services. Next, fidelity and brand are other most important factors and the name of store and risk are in lower degree of importance.

  4. Factors that Influence RF Breakdown in Antenna Systems

    Science.gov (United States)

    Caughman, J. B. O.; Baity, F. W.; Rasmussen, D. A.; Aghazarian, M.; Castano Giraldo, C. H.; Ruzic, David

    2007-11-01

    One of the main power-limiting factors in antenna systems is the maximum voltage that the antenna or vacuum transmission line can sustain before breaking down. The factors that influence RF breakdown are being studied in a resonant 1/4-wavelength section of vacuum transmission line terminated with an open circuit electrode structure. Breakdown can be initiated via electron emission by high electric fields and by plasma formation in the structure, depending on the gas pressure. Recent experiments have shown that a 1 kG magnetic field can influence plasma formation at pressures as low as 8x10-5 Torr at moderate voltage levels (LLC, for the U.S. Dept. of Energy under contract DE-AC05-00OR22725. Work supported by USDOE with grant DE-FG02-04ER54765

  5. Influence of breed and environmental factors on litter parameters of ...

    African Journals Online (AJOL)

    Influence of breed and environmental factors on litter parameters of rabbits ... There was a non-significant effect of season on litter site at birth, kits alive at birth and ... to rabbit reproduction as it influenced negatively more litter parameters than ...

  6. Factors influencing e-Procurement adoption in the Nigerian building industry

    Directory of Open Access Journals (Sweden)

    Eziyi Offia Ibem

    2016-12-01

    Full Text Available Against the backdrop of increasing adoption of e-Procurement in supply chain management, there is a need for adequate knowledge of the factors that influence the decision by organizations in the building industry to use e-Procurement. This study aims to fill the knowledge gap through investigating the factors influencing e-Procurement adoption based on the data sourced in a questionnaire survey involving 213 organizations in the building industry. The survey was conducted between June and November 2015 in Nigeria. Descriptive statistics, factor and categorical regression analyses were used to analyze the data. The results show that the three most important factors influencing the adoption of e-Procurement amongst the participants, in order of importance, were: the benefits of e-Procurement in enhancing efficiency in project delivery; eliminating geographic barriers and effective communication among project team members. The 29 factors were investigated in seven different dimensions - the benefits of e-Procurement use; level of awareness on e-Procurement in construction; and the availability and cost of e-Procurement applications emerged as the three most significant predictors of e-Procurement adoption in the survey. The study concludes by identifying strategies that should be engaged in increasing the uptake and maximizing the benefits of e-Procurement in the Nigerian building industry.

  7. Professionalism: the major factor influencing job satisfaction among Korean and Chinese nurses.

    Science.gov (United States)

    Hwang, J-I; Lou, F; Han, S S; Cao, F; Kim, W O; Li, P

    2009-09-01

    The nursing shortage has become an internationally important issue. Nurses' professionalism and job satisfaction have been recognized as strong factors influencing their turnover. As international interchanges in nursing education are growing between Korea and China, understanding the commonalities and differences in factors associated with job satisfaction is critical to improving nurses' job retention. To compare the factors influencing job satisfaction among Korean and Chinese nurses. A cross-sectional survey was conducted. The participants were comprised of 693 nurses at three general hospitals in Jinan, People's Republic of China and 593 nurses at two general hospitals in Seoul, Korea. A questionnaire was designed to measure the nurses' professionalism and job satisfaction. Stepwise multiple regression analysis was performed to identify factors related to job satisfaction. Professionalism was the common factor influencing job satisfaction in Korean and Chinese nurses. Professionalism was positively related to job satisfaction in both groups. Additional factors associated with job satisfaction were demographics and job characteristics such as age, job position and department of work, which were significant only in Korean nurses. Professionalism was the most important factor influencing job satisfaction in both Korean and Chinese nurses. Enhancing nursing professionalism is recommended as a common strategy to improve nurses' job retention across different healthcare systems.

  8. External factors influencing the environmental performance of South African firms

    CSIR Research Space (South Africa)

    Peart, R

    2001-01-01

    Full Text Available This article reviews the external factors that influence environmental performance of companies in South Africa, drawing on international and local literature. After considering factors within the natural, social, economic and institutional...

  9. Infrapopliteal Percutaneous Transluminal Balloon Angioplasty: Clinical Results and Influence Factors

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jang Hyeon; Lee, Seung Jin; Jung, Hye Doo; Lim, Jae Hoon; Chang, Nam Kyu; Yim, Nam Yeol; Kim, Jae Kyu [Dept. of Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of); Lee, Keun Bae [Dept. of Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of)

    2011-09-15

    To assess the efficacy of percutaneous transluminal angioplasty (PTA) in patients with infrapopliteal arterial disease, and to determine the influencing factor for prognosis. A total of 55 patients (60 limbs) with infrapopliteal arterial stenosis or occlusion underwent PTA. Atherosclerotic risk factors, clinical symptoms, TransAtlantic Inter-Society Consensus (TASC) classification, and vascular wall calcification were evaluated before PTA. The number of patent infrapopliteal arteries was estimated, and the outcome was evaluated by symptom relief and limb salvage. Technical success was achieved in 53/60 limbs (88.3%) and 81/93 arteries (87.1%), TASC classification (p = 0.038) and vascular calcification (p = 0.002) influenced on technical failure. During follow-up, 26 of 55 limbs (47%) achieved symptom relief and 42/55 limbs (76%) underwent limb salvage. Non-diabetic patients (9/12, 75%) were superior to diabetic patients (17/43, 40%) in terms of symptom relief (p = 0.024). TASC classification and vascular wall calcification influenced on symptom relief and limb salvage. The number of patent infrapopliteal arteries after PTA influenced symptom relief (p < 0.001) and limb amputation (p = 0.003). PTA in patients with chronic critical limb ischemia is worthwhile as a primary treatment. The influence factors should be considered before PTA, and PTA should be performed in as many involved arteries as possible.

  10. Infrapopliteal Percutaneous Transluminal Balloon Angioplasty: Clinical Results and Influence Factors

    International Nuclear Information System (INIS)

    Song, Jang Hyeon; Lee, Seung Jin; Jung, Hye Doo; Lim, Jae Hoon; Chang, Nam Kyu; Yim, Nam Yeol; Kim, Jae Kyu; Lee, Keun Bae

    2011-01-01

    To assess the efficacy of percutaneous transluminal angioplasty (PTA) in patients with infrapopliteal arterial disease, and to determine the influencing factor for prognosis. A total of 55 patients (60 limbs) with infrapopliteal arterial stenosis or occlusion underwent PTA. Atherosclerotic risk factors, clinical symptoms, TransAtlantic Inter-Society Consensus (TASC) classification, and vascular wall calcification were evaluated before PTA. The number of patent infrapopliteal arteries was estimated, and the outcome was evaluated by symptom relief and limb salvage. Technical success was achieved in 53/60 limbs (88.3%) and 81/93 arteries (87.1%), TASC classification (p = 0.038) and vascular calcification (p = 0.002) influenced on technical failure. During follow-up, 26 of 55 limbs (47%) achieved symptom relief and 42/55 limbs (76%) underwent limb salvage. Non-diabetic patients (9/12, 75%) were superior to diabetic patients (17/43, 40%) in terms of symptom relief (p = 0.024). TASC classification and vascular wall calcification influenced on symptom relief and limb salvage. The number of patent infrapopliteal arteries after PTA influenced symptom relief (p < 0.001) and limb amputation (p = 0.003). PTA in patients with chronic critical limb ischemia is worthwhile as a primary treatment. The influence factors should be considered before PTA, and PTA should be performed in as many involved arteries as possible.

  11. Nursing students' learning dynamics and influencing factors in clinical contexts.

    Science.gov (United States)

    Lee, Jung Jae; Clarke, Charlotte L; Carson, Maggie N

    2018-03-01

    Clinical placements are essential for students to develop clinical skills to qualify as nurses. However, various difficulties encountered by nursing students during their clinical education detract from developing clinical competencies. This constructivist grounded theory study aims to explore nursing students' experiences in clinical nursing education, and to identify the factors that influence the clinical education students receive. Twenty-one individual and six group semi-structured interviews were conducted with sixteen fourth year nursing students and four registered nurses. This research identified six factors that influence nursing students' clinical education: interpersonal, socio-cultural, instructional, environmental, emotional and physical factors. The research has developed a dynamic model of learning in clinical contexts, which offers opportunities to understand how students' learning is influenced multifactorially during clinical placements. The understanding and application of the model can improve nursing instructional design, and subsequently, nursing students' learning in clinical contexts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Factors influencing behavior in the forced swim test

    Science.gov (United States)

    Bogdanova, Olena V.; Kanekar, Shami; D’Anci, Kristen E.; Renshaw, Perry F.

    2017-01-01

    The forced swim test (FST) is a behavioral test in rodents which was developed in 1978 by Porsolt and colleagues as a model for predicting the clinical efficacy of antidepressant drugs. A modified version of the FST added the classification of active behaviors into swimming and climbing, in order to facilitate the differentiation between serotonergic and noradrenergic classes of antidepressant drugs. The FST is now widely used in basic research and the pharmaceutical screening of potential antidepressant treatments. It is also one of the most commonly used tests to assess depressive-like behavior in animal models. Despite the simplicity and sensitivity of the FST procedure, important differences even in baseline immobility rates have been reported between different groups, which complicate the comparison of results across studies. In spite of several methodological papers and reviews published on the FST, the need still exists for clarification of factors which can influence the procedure. While most recent reviews have focused on antidepressant effects observed with the FST, this one considers the methodological aspects of the procedure, aiming to summarize issues beyond antidepressant action in the FST. The previously published literature is analyzed for factors which are known to influence animal behavior in the FST. These include biological factors, such as strain, age, body weight, gender and individual differences between animals; influence of preconditioning before the FST: handling, social isolation or enriched environment, food manipulations, various kinds of stress, endocrine manipulations and surgery; schedule and routes of treatment, dosage and type of the drugs as well as experimental design and laboratory environmental effects. Consideration of these factors in planning experiments may result in more consistent FST results. PMID:23685235

  13. Factors Influencing the Spatial Difference in Household Energy Consumption in China

    Directory of Open Access Journals (Sweden)

    Yongxia Ding

    2016-12-01

    Full Text Available What factors determine the spatial heterogeneity of household energy consumption (HEC in China? Can the impacts of these factors be quantified? What are the trends and characteristics of the spatial differences? To date, these issues are still unclear. Based on the STIRPAT model and panel dataset for 30 provinces in China over the period 1997–2013, this paper investigated influences of the income per capita, urbanization level and annual average temperature on HEC, and revealed the spatial effects of these influencing factors. The results show that the income level is the main influencing factor, followed by the annual average temperature. There exists a diminishing marginal contribution with increasing income. The influence of urbanization level varies according to income level. In addition, from the eastern region to western region of China, variances largely depend upon economic level at the provincial level. From the northern region to southern region, change is mainly caused by temperature. The urbanization level has more significant impact on the structure and efficiency of household energy consumption than on its quantity. These results could provide reference for policy making and energy planning.

  14. [Coagulation factor VII levels in uremic patients and theirs influence factors].

    Science.gov (United States)

    Fang, Jun; Xia, Ling-Hui; Wei, Wen-Ning; Song, Shan-Jun

    2004-12-01

    This study was aimed to investigate coagulation factor VII level in uremic patients with chronic renal failure and to explore theirs influence factors. The plasma levels of coagulation factor VII were detected in 30 uremic patients with chronic renal failure before and after hemodialysis for 1 month, the factor VII activity (FVII:C) was determined by one-stage coagulation method, while activated factor VII (FVIIa) was measured by one-stage coagulation method using recombinant soluble tissue factor, and factor VII antigen was detected by ELISA. The results showed that: (1) The FVIIa, FVII:C and FVIIAg levels in chronic uremic patients before hemodialysis were 4.00 +/- 0.86 microg/L, (148.5 +/- 40.4)% and (99.8 +/- 21.1)% respectively, which were significantly increased, as compared with healthy controls [2.77 +/- 1.02 microg/L, (113.1 +/- 33.0)% and (73.7 +/- 18.3)% respectively, P factor VII was positively correlated with levels of blood uria nitrogen and serum creatinine before hemodialysis but not after hemodialysis. It is concluded that the enhanced levels of coagulation factor VII in chronic uremic patients suggested abnormal activated state, herperactivity and elevated production of factor VII which correlated with renal functional injury. The abnormality of factor VII in uremia may be aggravated by hemodialysis. Coagulation factor (FVII) may be a risk factor for cardiovascular events in uremic patients who especially had been accepted long-term hemodialysis.

  15. Factors influencing tinnitus loudness and annoyance.

    Science.gov (United States)

    Hiller, Wolfgang; Goebel, Gerhard

    2006-12-01

    To evaluate the 2 major components of tinnitus severity, loudness and annoyance, and their degree of dependence on characteristics of tinnitus manifestation, history, and etiology. Cross-sectional survey performed during the first months of 2004. Nonclinical population. A total of 4995 members of the German Tinnitus League. Comprehensive screening questionnaire, including the Klockhoff and Lindblom loudness grading system and the miniversion of the Tinnitus Questionnaire. A moderate correlation of 0.45 was found between tinnitus loudness and annoyance. Both factors were generally higher in men, those older than 50 years, those with binaural and centrally perceived tinnitus, those with increased noise sensitivity, and those who had continuous tinnitus without interruptions. Tinnitus that lasted 12 months or less had a stronger influence on annoyance (odds ratio [OR], 1.96) than on loudness (OR, 0.45), whereas the contrary was found for tinnitus of more than 5 years' duration (ORs, 0.72 and 2.11, respectively). Loudness and annoyance were increased in subjects with coexisting hearing loss, vertigo, and hyperacusis. The impact of hyperacusis on annoyance was clearly stronger than on loudness (ORs, 21.91 vs 9.47). Several clinical factors of tinnitus influence perceived loudness and annoyance. Both are distinguishable components of tinnitus severity.

  16. Assessing the Factors Influencing Women Attainment of Household ...

    African Journals Online (AJOL)

    This study assessed the factors influencing the attainment of household food security in Ikwuano ... Data analysis utilized descriptive statistics such as frequency counts, ... had no access to credits, 71.7% had no contact with extension service.

  17. Evaluation of some genetic factors influencing the phenotypic ...

    African Journals Online (AJOL)

    Evaluation of some genetic factors influencing the phenotypic severity of β thalassemia Egyptian patients. Ibtessam R Hussein, Amina M Medhat, Samir F Zohny, Alice K Abd El-Aleem, Ghada Y El-Kammah, Bardees M Foda ...

  18. Factors influencing the adoption of smartphones by undergraduate ...

    African Journals Online (AJOL)

    Factors influencing the adoption of smartphones by undergraduate students at ... ha ve thus far c oncentrated on the adoption of mobile technologies especially ... who may also want to explore the implementation of mobile learning systems, ...

  19. 38 FACTORS THAT INFLUENCE IRON STATUS OF PREGNANT ...

    African Journals Online (AJOL)

    sys01

    The study investigated the factors that influence iron ... approaches employed for promotion of girl-child education and prevention of adolescent .... purchase food items rich in haem iron such as ... decision making, life style options, and control.

  20. Analysis on influence factors of China's CO2 emissions based on Path-STIRPAT model

    International Nuclear Information System (INIS)

    Li Huanan; Mu Hailin; Zhang Ming; Li Nan

    2011-01-01

    With the intensification of global warming and continued growth in energy consumption, China is facing increasing pressure to cut its CO 2 (carbon dioxide) emissions down. This paper discusses the driving forces influencing China's CO 2 emissions based on Path-STIRPAT model-a method combining Path analysis with STIRPAT (stochastic impacts by regression on population, affluence and technology) model. The analysis shows that GDP per capita (A), industrial structure (IS), population (P), urbanization level (R) and technology level (T) are the main factors influencing China's CO 2 emissions, which exert an influence interactively and collaboratively. The sequence of the size of factors' direct influence on China's CO 2 emission is A>T>P>R>IS, while that of factors' total influence is A>R>P>T>IS. One percent increase in A, IS, P, R and T leads to 0.44, 1.58, 1.31, 1.12 and -1.09 percentage change in CO 2 emission totally, where their direct contribution is 0.45, 0.07, 0.63, 0.08, 0.92, respectively. Improving T is the most important way for CO 2 reduction in China. - Highlights: → We analyze the driving forces influencing China's CO 2 emissions. → Five macro factors like per capita GDP are the main influencing factors. → These factors exert an influence interactively and collaboratively. → Different factors' direct and total influence on China's CO 2 emission is different. → Improving technology level is the most important way for CO 2 reduction in China.

  1. The Factors Influencing Satisfaction with Public City Transport: A Structural Equation Modelling Approach

    Directory of Open Access Journals (Sweden)

    Pawlasova Pavlina

    2015-12-01

    Full Text Available Satisfaction is one of the key factors which influences customer loyalty. We assume that the satisfied customer will be willing to use the ssame service provider again. The overall passengers´ satisfaction with public city transport may be affected by the overall service quality. Frequency, punctuality, cleanliness in the vehicle, proximity, speed, fare, accessibility and safety of transport, information and other factors can influence passengers´ satisfaction. The aim of this paper is to quantify factors and identify the most important factors influencing customer satisfaction with public city transport within conditions of the Czech Republic. Two methods of analysis are applied in order to fulfil the aim. The method of factor analysis and the method Varimax were used in order to categorize variables according to their mutual relations. The method of structural equation modelling was used to evaluate the factors and validate the model. Then, the optimal model was found. The logistic parameters, including service continuity and frequency, and service, including information rate, station proximity and vehicle cleanliness, are the factors influencing passengers´ satisfaction on a large scale.

  2. Factors Influencing Student Nurses' Performance in the Final ...

    African Journals Online (AJOL)

    Factors Influencing Student Nurses' Performance in the Final Practical Examination ... Staff development courses can be held to coordinate the work of the school ... to authentic individual nursing care of patients so that they use the individual ...

  3. Factors influencing breastfeeding practices in Edo state, Nigeria ...

    African Journals Online (AJOL)

    In Nigeria however, young infants may not benefit from such a practice as a ... The purpose of this study was to determine factors influencing breastfeeding practices in Edo State, Nigeria. ... Only 20 per cent practiced exclusive breastfeeding.

  4. Factors of influence and changes in the tourism consumer behaviour

    Directory of Open Access Journals (Sweden)

    Fratu, D.

    2011-01-01

    Full Text Available Consumer behaviour is a very important aspect to be studied in every marketing activity, therefore in tourism marketing as well. Defining and identifying the factors that influence consumers help in understanding individual needs and buying processes in their whole complexity. Consumers have changed their behaviour over the last two years due to the instability of the economic environment. The author describes in this article the factors which influence consumer behaviour and also presents how it has changed over the past two years.

  5. FACTORS INFLUENCING THE MANAGEMENT OF ADHD

    OpenAIRE

    S ARMAN; M SOLTANI

    2003-01-01

    Introduction: Attention deficit hyperactivity disorder (ADHD)is the most common psychiatric disorder among school age children. It consists of hyperactivity, inattention and impulsive behavior. The onset of the disorder is before the age of 7 years and it happens at least in two situations. It causes significant impairment in social and academic functioning. A determination of factors that influences the therapeutic response in ADHD is the aim of this study. Methods: This study is design...

  6. The influence of family factors on delinquent adolescents in ...

    African Journals Online (AJOL)

    This study was carried out with the aim of finding out the influence of family factors on delinquent adolescents in secondary schools in Edo South Senatorial District of Edo State. This study ascertained the extents to which family factors such as parent child rearing style, family type and parent socio economic background ...

  7. Modeling the factors that influence knowledge transfer in mergers and acquisitions

    Institute of Scientific and Technical Information of China (English)

    YU Haiyan; LIANG Zhanping

    2010-01-01

    This paper constructs a model on the factors that influence knowledge transfer in mergers and acquisitions (M&A) and validates it via questionnaire surveys.Using 125 valid collected questionnaires,multiple linear regression analysis and hierarchical regression analysis showed that five out of the ten factors had a positive effect on knowledge transfer effect.The ranking of factor importance,from high to low,was knowledge explicitness,relationship quality,learning intent,advanced transfer activities,and learning capability,which is fairly consistent with positive factors observed in other interorganizational knowledge transfer researches.Our results also showed that one of the control variables (size of acquired firm) had neither a direct or indirect effect on knowledge transfer in M&A.Additionally,our research found that knowledge distance and degree of M&A integration had a positive influence on knowledge transfer effect at the early stage after M&A,but had a negative influence at the late stage.Based on this research,several suggestions for knowledge transfer in M&A are proposed.

  8. Modeling the factors that influence knowledge transfer in mergers and acquisitions

    Institute of Scientific and Technical Information of China (English)

    YU; Haiyan; LIANG; Zhanping

    2010-01-01

    This paper constructs a model on the factors that influence knowledge transfer in mergers and acquisitions(M&A)and validates it via questionnaire surveys.Using 125valid collected questionnaires,multiple linear regression analysis and hierarchical regression analysis showed that five out of the ten factors had a positive effect on knowledge transfer effect.The ranking of factor importance,from high to low,was knowledge explicitness,relationship quality,learning intent,advanced transfer activities,and learning capability,which is fairly consistent with positive factors observed in other interorganizational knowledge transfer researches.Our results also showed that one of the control variables(size of acquired firm)had neither a direct or indirect effect on knowledge transfer in M&A.Additionally,our research found that knowledge distance and degree of M&A integration had a positive influence on knowledge transfer effect at the early stage after M&A,but had a negative influence at the late stage.Based on this research,several suggestions for knowledge transfer in M&A are proposed.

  9. A Study of Factors Influencing International Students' Choice of Higher Education Institutions

    OpenAIRE

    Akadu, Victor Abia

    2013-01-01

    This paper discusses the factors that influence international students’ choice of higher education institutions. The research conducted using the international students in the University of Nottingham (Malaysia Campus) and Monash University (Malaysia Campus) and survey questionnaires were mainly used to gather primary data for the purpose of this study. Findings from this research indicated that product and university based factors, cost factors, promotion, location and social influences all ...

  10. Factors influencing recruitment and retention of professional nurses ...

    African Journals Online (AJOL)

    J. Lyn Haskins

    factors influencing recruitment and retention of three categories of HPs in KwaZulu-Natal and has ...... tion, with good career opportunities which were similar in both urban and rural .... attract nurses to rural areas: A multicountry discrete choice.

  11. Perceived factors influencing the utilization of traditional birth ...

    African Journals Online (AJOL)

    Perceived factors influencing the utilization of traditional birth attendants' services in ... A total of 130 questionnaires were retrieved and analyzed using statistical ... Poverty (p=0.988) and educational level (p =0.133) were not found to be ...

  12. Factors influencing adherence to dietary guidelines: a qualitative ...

    African Journals Online (AJOL)

    2014-01-17

    Jan 17, 2014 ... Original Research: Factors influencing adherence to dietary guidelines. 76. 2014 Volume ..... eat, because they dik (tired) of giving you special food. Then they go .... patients in this study were satisfied with the advice received ...

  13. Factors influencing Nigerian men's decision to undergo prostate ...

    African Journals Online (AJOL)

    Objective: This study explores the factors that influence a group of Nigerian men's decision to go for Prostate Specific ..... older they were in the habit of regularly visiting the hospi- .... friends with prostate cancer was an important stimulus.

  14. Evaluation of the efficacy of factors influencing on marketing SMEs

    Directory of Open Access Journals (Sweden)

    Mona Yaghoubi

    2014-07-01

    Full Text Available This paper presents an empirical investigation to study the effects of different factors influencing on marketing in small and medium enterprises (SMEs in city of Tehran, Iran. The study has been accomplished among 57 SMEs out of 70 active business units who were involved in hand made carpet. The survey uses a questionnaire originally developed by Merrilees et al. (2011 [Merrilees, B., Rundle-Thiele, S., & Lye, A. (2011. Marketing capabilities: Antecedents and implications for B2B SME performance. Industrial Marketing Management, 40(3, 368-375.] to determine the factors influencing on marketing SMEs. Using structural equation modeling, the results of survey indicate that market orientation, management capability, innovation capability and brand capability of SME's marketing performance influence on development of marketing, positively.

  15. Organizational factors influencing successful primary care and public health collaboration.

    Science.gov (United States)

    Valaitis, Ruta; Meagher-Stewart, Donna; Martin-Misener, Ruth; Wong, Sabrina T; MacDonald, Marjorie; O'Mara, Linda

    2018-06-07

    Public health and primary care are distinct sectors within western health care systems. Within each sector, work is carried out in the context of organizations, for example, public health units and primary care clinics. Building on a scoping literature review, our study aimed to identify the influencing factors within these organizations that affect the ability of these health care sectors to collaborate with one another in the Canadian context. Relationships between these factors were also explored. We conducted an interpretive descriptive qualitative study involving in-depth interviews with 74 key informants from three provinces, one each in western, central and eastern Canada, and others representing national organizations, government, or associations. The sample included policy makers, managers, and direct service providers in public health and primary care. Seven major organizational influencing factors on collaboration were identified: 1) Clear Mandates, Vision, and Goals; 2) Strategic Coordination and Communication Mechanisms between Partners; 3) Formal Organizational Leaders as Collaborative Champions; 4) Collaborative Organizational Culture; 5) Optimal Use of Resources; 6) Optimal Use of Human Resources; and 7) Collaborative Approaches to Programs and Services Delivery. While each influencing factor was distinct, the many interactions among these influences are indicative of the complex nature of public health and primary care collaboration. These results can be useful for those working to set up new or maintain existing collaborations with public health and primary care which may or may not include other organizations.

  16. FACTORS INFLUENCING YIELD SPREADS OF THE MALAYSIAN BONDS

    OpenAIRE

    Norliza Ahmad; Joriah Muhammad; Tajul Ariffin Masron

    2009-01-01

    Malaysian bond market is developing rapidly but not much is understood in terms of macroeconomic factors that could influence the yield spread of the Ringgit Malaysian denominated bonds. Based on a multifactor model, this paper examines the impact of four macroeconomic factors namely: Kuala Lumpur Composite Index (KLCI), Industry Production Index (IPI), Consumer Price Index (CPI) and interest rates (IR) on bond yield spread of the Malaysian Government Securities (MGS) and Corporate Bonds (CBs...

  17. FACTORS INFLUENCING BRAND LOYALTY IN PROFESSIONAL SPORTS FANS

    OpenAIRE

    Yun-Tsan Lin; Chen-Hsien Lin

    2008-01-01

    Many researchers have provided comprehensive definitions for the term of brand loyalty and also examined the factors affecting brand loyalty with many empirical studies. But there is little research focusing on the brand loyalty of professional sports fans. The topic area about factors influencing brand loyalty in professional sports fans was identified because these fans bring significant financial benefits every year and stimulate economic growth in the United States. Although different con...

  18. Research on Influencing Factors of Salespeople's Empowerment Readiness in Green Energy Enterprise

    Science.gov (United States)

    Dong, Yuan; Liu, Xiaohui

    As market competition in green energy enterprises continues to intensify, marketing activities are enlarging and customer demand is increasingly growing and diversifying. More and more green energy enterprises have empowered their own salespeople. And managers in green energy enterprises are more concerned with the issues which employees suit to be empowered and which factors will influence employee empowerment readiness. This paper proposes the definition of salespeople's empowerment readiness, analyzes influencing factors of salespeople's empowerment readiness, discusses the effect mechanism of influencing factors of salespeople's empowerment readiness, finally, and puts forward some suggestions to enhance salespeople's empowerment readiness from the perspective of human resource management practice.

  19. Factors influencing the density of aerobic granular sludge.

    NARCIS (Netherlands)

    Winkler, M.K.; Kleerebezem, R.; Strous, M.; Chandran, K.; Loosdrecht, M.C. van

    2013-01-01

    In the present study, the factors influencing density of granular sludge particles were evaluated. Granules consist of microbes, precipitates and of extracellular polymeric substance. The volume fractions of the bacterial layers were experimentally estimated by fluorescent in situ hybridisation

  20. Factors Which Influence The Fish Purchasing Decision: A study on Traditional Market in Riau Mainland

    Science.gov (United States)

    Siswati, Latifa; Putri, Asgami

    2018-05-01

    The purposes of the research are to analyze and assess the factors which influence fish purchasing by the community at Tenayan Raya district Pekanbaru.Research methodology which used is survey method, especially interview and observation technique or direct supervision on the market which located at Tenayan Raya district. Determination technique of sampling location/region is done by purposive sampling. The sampling method is done by accidental sampling. Technique analysis of factors which used using the data that derived from the respondent opinion to various fish variable. The result of this research are the factors which influence fish purchasing decision done in a traditional market which located at Tenayan Raya district are product factor, price factors, social factor and individual factor. Product factor which influences fish purchasing decision as follows: the eyelets condition, the nutrition of fresh fish, the diversity of sold fish. Price factors influence the fish purchasing decision, such as: the price of fresh fish, the convincing price and the suitability price and benefits of the fresh fish. Individual factors which influence a fish purchasing decision, such as education and income levels. Social factors which influence a fish purchasing decision, such as family, colleagues and feeding habits of fish.

  1. Generational Approach to Factors Influencing Career Choice in Accounting

    Directory of Open Access Journals (Sweden)

    Jony Hsiao

    Full Text Available ABSTRACT This research aims to grasp which factors influence the generation Y to choose accounting as its career. A significant decline in the number of candidates willing to pursue a career as accountant has been observed abroad - USA, Australia, and Japan. However, in other countries - Brazil, Singapore, and Hong Kong - the opposite has been observed. Another issue is the decline in educational qualification of those pursuing an accounting career, contributing in a way that many talented students change their career choice. This may be explained by the fact that people tend to believe accounting is an exact science, full of calculations, boring, and not very creative, bringing an unbalance between the traits an individual should have according to the job market and those perceived by society. In order to give a contribution to literature concerning the factors that influence the generation Y in its career choice, a goal of this research was conducting an exploratory study where some hypotheses were formulated to support the discussion. We used Mannheim's Generational Theory and the literature on career choice. Data collection was carried out using a questionnaire, based on Schwartz's Portrait Value Questionnaire and Germeijs and Verschueren's Student Choice Task Inventory, adapted through focus group interview. Data were fully collected online and the sample consisted of 665 subjects. The results showed that people who chose accounting as their career were influenced by factors such as creativity, independence, challenging and dynamic environment, job security, money-making, job availability, and other significant people - friends and teachers. The subjects were not influenced by social factors, such as working with people and making contributions to society and family. They wish for more autonomy, creativity, and flexibility at work, and people still care about job security and money-making.

  2. Factors influencing elderly women's mammography screening decisions: implications for counseling.

    Science.gov (United States)

    Schonberg, Mara A; McCarthy, Ellen P; York, Meghan; Davis, Roger B; Marcantonio, Edward R

    2007-11-16

    Although guidelines recommend that clinicians consider life expectancy before screening older women for breast cancer, many older women with limited life expectancies are screened. We aimed to identify factors important to mammography screening decisions among women aged 80 and older compared to women aged 65-79. Telephone surveys of 107 women aged 80+ and 93 women aged 65-79 randomly selected from one academic primary care practice who were able to communicate in English (60% response rate). The survey addressed the following factors in regards to older women's mammography screening decisions: perceived importance of a history of breast disease, family history of breast cancer, doctor's recommendations, habit, reassurance, previous experience, mailed reminder cards, family/friend's recommendations or experience with breast cancer, age, health, and media. The survey also assessed older women's preferred role in decision making around mammography screening. Of the 200 women, 65.5% were non-Hispanic white and 82.8% were in good to excellent health. Most (81.3%) had undergone mammography in the past 2 years. Regardless of age, older women ranked doctor's recommendations as the most important factor influencing their decision to get screened. Habit and reassurance were the next two highly ranked factors influencing older women to get screened. Among women who did not get screened, women aged 80 and older ranked age and doctor's counseling as the most influential factors and women aged 65-79 ranked a previous negative experience with mammography as the most important factor. There were no significant differences in preferred role in decision-making around mammography screening by age, however, most women in both age groups preferred to make the final decision on their own (46.6% of women aged 80+ and 50.5% of women aged 65-79). While a doctor's recommendation is the most important factor influencing elderly women's mammography screening decisions, habit and reassurance

  3. Risk Factors Influencing Construction Procurement Performance in Nigeria

    Directory of Open Access Journals (Sweden)

    Alhassan Dahiru

    2015-08-01

    Full Text Available One of the challenges facing construction procurement performance is the failure to determine the risk related factors limiting its success. These risk factors can cause a significant increase in the procurement cost leading to an increase in the overall project cost. The purpose of this study is to identify and evaluate the risk factors influencing construction procurement performance with a view to achieve the overall project performance. The objectives are to establish a relative significance index score for the most important risk factors limiting the procurement performance of the projects. A self administered questionnaire was employed to the construction industry professionals for responses. A total of 78 questionnaires were distributed to these professionals (architects, quantity surveyors, engineers, and contractors but 62 were returned and analyzed using influential index and later ranked in order of importance. Results of the analysis indicate a disparity in terms of ranking of the factors influencing construction procurement performance. Corruption related risk, conflict of interest, ineffective project technical feasibility, and lack of commitment to transparency were found to be the most significant factors limiting construction procurement performance. Communication barriers and unconfidential tender evaluation process were found to be the low weighted risk factors. The findings can serve as a supportive mechanism for risks management in public construction procurement management. Therefore, construction procurement personnel at all levels of government may find this study relevant, while improving construction procurement performance in the country. It is recommended that construction procurement system should be focused on risks related to corruption, conflict of interest, and effective technical feasibility for improving the overall project performance.

  4. Domain-General Factors Influencing Numerical and Arithmetic Processing

    Directory of Open Access Journals (Sweden)

    André Knops

    2017-12-01

    Full Text Available This special issue contains 18 articles that address the question how numerical processes interact with domain-general factors. We start the editorial with a discussion of how to define domain-general versus domain-specific factors and then discuss the contributions to this special issue grouped into two core numerical domains that are subject to domain-general influences (see Figure 1. The first group of contributions addresses the question how numbers interact with spatial factors. The second group of contributions is concerned with factors that determine and predict arithmetic understanding, performance and development. This special issue shows that domain-general (Table 1a as well as domain-specific (Table 1b abilities influence numerical and arithmetic performance virtually at all levels and make it clear that for the field of numerical cognition a sole focus on one or several domain-specific factors like the approximate number system or spatial-numerical associations is not sufficient. Vice versa, in most studies that included domain-general and domain-specific variables, domain-specific numerical variables predicted arithmetic performance above and beyond domain-general variables. Therefore, a sole focus on domain-general aspects such as, for example, working memory, to explain, predict and foster arithmetic learning is also not sufficient. Based on the articles in this special issue we conclude that both domain-general and domain-specific factors contribute to numerical cognition. But the how, why and when of their contribution still needs to be better understood. We hope that this special issue may be helpful to readers in constraining future theory and model building about the interplay of domain-specific and domain-general factors.

  5. Factors influencing exacerbation-related self-management in patients with COPD: a qualitative study.

    Science.gov (United States)

    Korpershoek, Yjg; Vervoort, Scjm; Nijssen, Lit; Trappenburg, Jca; Schuurmans, M J

    2016-01-01

    In patients with COPD, self-management skills are important to reduce the impact of exacerbations. However, both detection and adequate response to exacerbations appear to be difficult for some patients. Little is known about the underlying process of exacerbation-related self-management. Therefore, the objective of this study was to identify and explain the underlying process of exacerbation-related self-management behavior. A qualitative study using semi-structured in-depth interviews was performed according to the grounded theory approach, following a cyclic process in which data collection and data analysis alternated. Fifteen patients (male n=8; age range 59-88 years) with mild to very severe COPD were recruited from primary and secondary care settings in the Netherlands, in 2015. Several patterns in exacerbation-related self-management behavior were identified, and a conceptual model describing factors influencing exacerbation-related self-management was developed. Acceptance, knowledge, experiences with exacerbations, perceived severity of symptoms and social support were important factors influencing exacerbation-related self-management. Specific factors influencing recognition of exacerbations were heterogeneity of exacerbations and habituation to symptoms. Feelings of fear, perceived influence on exacerbation course, patient beliefs, ambivalence toward treatment, trust in health care providers and self-empowerment were identified as specific factors influencing self-management actions. This study provided insight into factors influencing exacerbation-related self-management behavior in COPD patients. The conceptual model can be used as a framework for health care professionals providing self-management support. In the development of future self-management interventions, factors influencing the process of exacerbation-related self-management should be taken into account.

  6. Franchised fast food brands: An empirical study of factors influencing growth

    OpenAIRE

    Christopher A. Wingrove; Boris Urban

    2017-01-01

    Orientation: Franchising is a popular and multifaceted business arrangement that captures a sizeable portion of the restaurant industry worldwide. Research purpose: The study empirically investigated the influence of various site location and branding factors on the growth of franchised fast food restaurant brands across the greater Gauteng region. Motivation of the study: Researching which factors influence the growth of franchised fast food restaurant brands is important for an emer...

  7. Factors influencing endometrial thickness in postmenopausal women.

    Science.gov (United States)

    Hebbar, S; Chaya, V; Rai, L; Ramachandran, A

    2014-07-01

    Cut-off values for endometrial thickness (ET) in asymptomatic postmenopausal woman have been standardized. However, there are no comprehensive studies to document how various factors can influence the ET after the age of menopause. To study the various factors influencing the ET in postmenopausal women. This was a prospective observational study. A total of 110 postmenopausal women underwent detailed history taking, clinical examination, and transvaginal scan for uterine volume and ovarian volume. The volumes were calculated by using ellipsoid formula: Width × thickness × height × 0.523. The variation in ET with respect to the influencing factors such as age, duration of menopause, parity, body mass index (BMI), medical illness like diabetes/hypertension, drugs like tamoxifen, presence of myoma, uterine volume, ovarian volume, and serum estradiol (in selected patients) were measured. Descriptive analysis was performed using SPSS software (version 16, Chicago II, USA) to obtain mean, standard deviation (SD), 95% confidence intervals (CIs) and inter quartile ranges. Comparison of means was carried out using analysis of variance. The mean (SD) age of the patients was 55.4 (6.91) years (95% CI, 54.1, 56.7). The mean (SD) age at menopause was 47.95 (3.90) years (95% CI, 47.2, 48.7) and the mean (SD) duration of menopause was 7.27 (6.65) years (95% CI, 6.01, 8.53). The mean (SD) ET was 3.8 (2.3) mm (95% CI, 3.36, 4.23). Medical illness like diabetes and hypertension did not alter the ET. ET increased as BMI increased and it was statistically significant. The presence of myoma increased uterine volume significantly and was associated with thick endometrial stripe. Similarly, whenever the ovaries were visualized and as the ovarian volume increased, there was an increase in ET. When ET was > 4 mm (n = 37), they were offered endocel, of which 16 agreed to undergo the procedure. None were found to have endometrial cancer. This study suggests that parity, BMI, presence of

  8. Factors Influencing Adjustment to Late-Life Divorce.

    Science.gov (United States)

    Wilson, Keren Brown; DeShane, Michael R.

    Although the rate of divorce among older Americans has increased steadily, little attention has been paid to late life divorce. To describe the role of age and other factors which might influence adjustment to divorce in later life, data from a larger pilot study were used: 81 divorced persons over the age of 60 completed in-depth, structured…

  9. Factors Influencing the Willingness to Pay User Fees

    OpenAIRE

    Morse, George W.

    2012-01-01

    In this Note I explore the factors which influence the demand side of program participation, or the willingness to pay (WTP). The WTP estimates can help you determine how many people will participate in an event at each fee level.

  10. Factors that influence on the decisions of battered women

    Directory of Open Access Journals (Sweden)

    Juana Robledo Martín

    2008-01-01

    Full Text Available Violence towards and against women consists in any kind of violation of woman’s personality, her physical integrity or her freedom of movement. Nowadays, gender-based violence is considered a state and public health problem as well as a social concerning subject.Objective: To identify the factors that influence on the decisions that battered women make.Methodology: The study population are battered women who live in Madrid province and who are being attended in the Municipal Points of the Regional Observatory against the Gender Violence.The information was collected by performing focus groups and deep interviews.Results: There are several factors which influence on the decisions that battered women make, like the existence or not of children they have to take care of, the economic dependence and the ignorance of the woman, in some cases, of the existence of this ill-treatment, but over all, we could even say beyond all these, there is one that is the most important, common and we could say it is the main axis that determine their behaviour. This factor is fear.Discussion: When attending these women we may be aware of the psychological situation they are, and we should be able to identify if the woman is asking us for help when she comes to us and try to identify and treat this factor that influences the decisions the woman we attend makes.

  11. Factors Influencing the Effectiveness of Inventory Management in Manufacturing SMEs

    Science.gov (United States)

    Chan, Shiau Wei; Tasmin, R.; Nor Aziati, A. H.; Zuraidah Rasi, Raja; Ismail, Fadillah Binti; Yaw, Li Ping

    2017-08-01

    Effectiveness of inventory management is a vital part in the manufacturing organization to be more competitive. The previous studies have indicated that there are several factors influencing the effectiveness of inventory management in the organization but there is lack of researchers who carried out the research in the manufacturing small medium enterprise in Johor. Therefore, the purpose of this research is to identify the problem of inventory management faced by the manufacturing small medium enterprise and also to determine the factors that will influence the effectiveness of inventory management. In completing this research, 80 employees were selected randomly from the manufacturing small medium enterprise in Batu Pahat, Johor and they were requested to complete questionnaires. The result have shown that the problems of inventory management faced by manufacturing organization were underproduction, overproduction, stock out situation, delays in the delivery of raw materials and discrepancy of records. The factors, documentation/store records, planning, knowledge of employees/staff skill have shown to significantly influence the effectiveness of inventory management while the funds have shown slightly significant influence on the inventory management in manufacturing small medium enterprises. This quantitative study is important to the manufacturing organization in Malaysia because it provides the guidelines to the employers of manufacturing small medium enterprises in Batu Pahat, Johor.

  12. Cheap Talk: “Team Factors and Management Practices Influence on Team Trust”

    OpenAIRE

    Doris Padmini Selvaratnam; Aini Aman; Muhamad Maziz Mahyuddin Bin Kamaludin; Gary Lynn; Richard Reilly

    2016-01-01

    Team trust has been cited as a contributing factor towards team performance. This paper looks at the antecedents of team trust and to what extent they influence team trust. The antecedents of team trust are team factors like team autonomy, team stability and team member experience; and the management practices are top management involvement and management support. The results demonstrated that team factors and management practices influence team trust individually. The key find...

  13. ESTIMATION OF EXTERNAL FACTORS INFLUENCE ON THE ORGANIZATIONAL AND RESOURCE SUPPORT OF ENGINEERING

    Directory of Open Access Journals (Sweden)

    Yu. V. Gusak

    2013-09-01

    Full Text Available Purpose. The engineering industry is characterized by deep specialization and high co-operation, which suggests a high degree of interaction with other industries and the economy, highly sensitive to external factors. Effective regulation of the engineering industry’s organizational-resource support will ensure coherence of all the subsystems of the market economy, the competitive environment, a full course of the investment process and the success of the industry. Therefore there is a need for detailed estimation and analysis of the external factors’ influence on the formation and implementation indexes of the engineering industry’s organizational-resource support. Methodology. To establish the close connection between the set of external factors of formation and implementation indexes of the engineering industry organizational-resource support the correlation analysis was used, to calculate the amount of the formation and implementation indexes of the engineering industry organizational-resource support’s change under the influence of the external factors with malleability coefficient were applied. Findings. The external influence factors on the engineering industry organizational-resource support by the source of origin: industrial, economical, political, informational, and social were separated and grouped. The classification of the external factors influence on the engineering industry organizational-resource support, depending on their influence’s direction on the formation and implementation indexes of the engineering industry’s organizational-resource support was made. The connection closeness and the amount of the formation and implementation indexes of the engineering industry organizational-resource support change (the machinery index of and the sales volume machinery index under the influence of the external factors with malleability coefficient were determined. Originality. The estimation of the external factors

  14. An exploration study on factors influencing green marketing

    Directory of Open Access Journals (Sweden)

    Mojtaba Esmaeeli

    2013-05-01

    Full Text Available These days, there have been tremendous efforts on offering products, which are environment friendly. Green marketing plays an important role for attracting new customer and customer retention. This paper presents an empirical investigation based on the implementation of factor analysis to locate important factors influencing green marketing planning and strategies. building market oriented business units. The study designs a questionnaire including 23 questions and the questionnaire was distributed among 200 people who were visiting organic product exhibition. Cronbach alpha was calculated as 0.845, which is well above the minimum acceptable limit and validates the results. The results of factor analysis reveal four major factors including green labeling, compatibility, product value and marketing component and size.

  15. SEM study of the effects of crude oil on the gills and air breathing organs of climbing perch, Anabas testudineus

    International Nuclear Information System (INIS)

    Prasad, M.S.

    1991-01-01

    Ultrastructural studies on the effects of crude oil on the gills are scanty. Recently, researchers studied the effect of crude oil on the air breathing organs of striped gourami using scanning electron microscope and observed mucous cell hyperplasia coupled with telangiectasis in the epithelia of air breathing organs. The present investigation has been undertaken to study crude oil toxicity by observing the morphological changes occurring in the epithelia of gills and air breathing organs of climbing perch, Anabas testudineus at SEM level. Since the epithelia of gills and air breathing organs function in two different media, a comparative account for their sensitivity to crude oil solutions would be informative

  16. Factors influencing societal response of nanotechnology : an expert stakeholder analysis

    NARCIS (Netherlands)

    Gupta, N.; Fischer, A.R.H.; Lans, van der I.A.; Frewer, L.J.

    2012-01-01

    Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an

  17. Factors Influencing Acceptance Of Contraceptive Methods

    Directory of Open Access Journals (Sweden)

    Anita Gupta

    1997-04-01

    Full Text Available Research Problem: What are the factors influencing acceptance of contraceptive methods. Objective: To study the determinants influencing contra­ceptive acceptance. Study design: Population based cross - sectional study. Setting: Rural area of East Delhi. Participants: Married women in the reproductive age group. Sample:Stratified sampling technique was used to draw the sample. Sample Size: 328 married women of reproductive age group. Study Variables: Socio-economic status, Type of contraceptive, Family size, Male child. Outcome Variables: Acceptance of contraceptives Statistical Analysis: By proportions. Result: Prevalence of use of contraception at the time of data collection was 40.5%. Tubectomy and vasectomy were most commonly used methods. (59.4%, n - 133. Educational status of the women positively influenced the contraceptive acceptance but income did not. Desire for more children was single most important deterrent for accepting contraception. Recommendations: (i             Traditional method of contraception should be given more attention. (ii            Couplesshould be brought in the contraceptive use net at the early stage of marriage.

  18. Influencing Factors of the Initiation Point in the Parachute-Bomb Dynamic Detonation System

    Science.gov (United States)

    Qizhong, Li; Ye, Wang; Zhongqi, Wang; Chunhua, Bai

    2017-12-01

    The parachute system has been widely applied in modern armament design, especially for the fuel-air explosives. Because detonation of fuel-air explosives occurs during flight, it is necessary to investigate the influences of the initiation point to ensure successful dynamic detonation. In fact, the initiating position exist the falling area in the fuels, due to the error of influencing factors. In this paper, the major influencing factors of initiation point were explored with airdrop and the regularity between initiation point area and factors were obtained. Based on the regularity, the volume equation of initiation point area was established to predict the range of initiation point in the fuel. The analysis results showed that the initiation point appeared area, scattered on account of the error of attitude angle, secondary initiation charge velocity, and delay time. The attitude angle was the major influencing factors on a horizontal axis. On the contrary, secondary initiation charge velocity and delay time were the major influencing factors on a horizontal axis. Overall, the geometries of initiation point area were sector coupled with the errors of the attitude angle, secondary initiation charge velocity, and delay time.

  19. Factors Influencing New Entrant Dairy Farmer's Decision-Making Process around Technology Adoption

    Science.gov (United States)

    McDonald, Roberta; Heanue, Kevin; Pierce, Karina; Horan, Brendan

    2016-01-01

    Purpose: The aims of this paper are to (1) evaluate the main factors influencing grazing system technology adoption among new entrant (NE) dairy farmers within Europe and the Irish pasture-based dairy industry, and (2) to determine the extent to which economic factors influence decision-making around technology adoption and use among NEs to the…

  20. Effects of freezing on white perch Morone americana (Gmelin, 1789): Implications for multivariate morphometrics

    Science.gov (United States)

    Kocovsky, Patrick

    2016-01-01

    This study tested the hypothesis that duration of freezing differentially affects whole-body morphometrics of a derived teleost. Whole-body morphometrics are frequently analyzed to test hypotheses of different species, or stocks within a species, of fishes. Specimens used for morphometric analyses are typically fixed or preserved prior to analysis, yet little research has been done on how fixation or preservation methods or duration of preservation of specimens might affect outcomes of multivariate statistical analyses of differences in shape. To determine whether whole-body morphometrics changed as a result of freezing, 23 whole-body morphometrics of age-1 white perch (Morone americana) from western Lake Erie (n = 211) were analyzed immediately after capture, after being held on ice overnight, and after freezing for 100 or 200 days. Discriminant function analysis revealed that all four groups differed significantly from one another (P time to avoid biases related to the length of time they were frozen. Similar experiments should be conducted on other species and also using formalin- and alcohol-preserved specimens.

  1. Factors Influencing Choice of Inguinal Hernia Repair Technique ...

    African Journals Online (AJOL)

    Background: Inguinal hernia repair surgery is one of the most frequently performed surgical procedures worldwide. This study sought to highlight factors that may influence decisions concerning inguinal hernia repair techniques. Methods: This descriptive crosssectional study was carried out in September 2014 among ...

  2. Influence of Sociodemographic Factors on Job Burnout and ...

    African Journals Online (AJOL)

    Influence of Sociodemographic Factors on Job Burnout and Satisfaction among ... (ii) female medical personnel showed significantly greater degree of job satisfaction than ... level of job satisfaction than older employees and, (iv) married employees found significantly more job satisfaction than their unmarried counterparts.

  3. Logistic Regression and Path Analysis Method to Analyze Factors influencing Students’ Achievement

    Science.gov (United States)

    Noeryanti, N.; Suryowati, K.; Setyawan, Y.; Aulia, R. R.

    2018-04-01

    Students' academic achievement cannot be separated from the influence of two factors namely internal and external factors. The first factors of the student (internal factors) consist of intelligence (X1), health (X2), interest (X3), and motivation of students (X4). The external factors consist of family environment (X5), school environment (X6), and society environment (X7). The objects of this research are eighth grade students of the school year 2016/2017 at SMPN 1 Jiwan Madiun sampled by using simple random sampling. Primary data are obtained by distributing questionnaires. The method used in this study is binary logistic regression analysis that aims to identify internal and external factors that affect student’s achievement and how the trends of them. Path Analysis was used to determine the factors that influence directly, indirectly or totally on student’s achievement. Based on the results of binary logistic regression, variables that affect student’s achievement are interest and motivation. And based on the results obtained by path analysis, factors that have a direct impact on student’s achievement are students’ interest (59%) and students’ motivation (27%). While the factors that have indirect influences on students’ achievement, are family environment (97%) and school environment (37).

  4. An empirical investigation on factors influencing on brand loyalty

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2013-07-01

    Full Text Available Building a competitive brand is a key success specially in banking industry. This paper presents a study to investigate important factors influencing brand loyalty among special customers in one of biggest Iranian banks in Iran. The study designs a questionnaire and distributes it among 249 regular customers who are special customers in various banks in city of Tehran, Iran. The study uses structural equation modeling to find important factors and they are ranked using TOPSIS method. In our study, Cronbach alpha has been calculated as 0.815 and there are eight influencing factors including flexibility in offering various services, building good relationship with customers, technology and processes, customers’ experiences, brand identity in continuous advertisement, organization size, customer perception on reputation of brand and customers’ tendency to build better brand loyalty. In our survey, flexibility in offering various services received the highest rank followed by building good relationship with customers.

  5. Emergency Department Crowding: Factors Influencing Flow

    OpenAIRE

    Arkun, Alp; Briggs, William M; Patel, Sweha; Datillo, Paris A; Bove, Joseph; Birkhahn, Robert H

    2010-01-01

    Background: The objective of this study was to evaluate those factors, both intrinsic and extrinsic to the emergency department (ED) that influence two specific components of throughput: “door-to-doctor” time and dwell time. Methods: We used a prospective observational study design to determine the variables that played a significant role in determining ED flow. All adult patients seen or waiting to be seen in the ED were observed at 8pm (Monday-Friday) during a three-month period. V...

  6. Determinant factors influencing efficiency of Fadama Arable crop ...

    African Journals Online (AJOL)

    ... farm income, output, productivity and farm size and determined factors influencing Fadama farmer's efficiency. The multistage sampling technique was employed in the selection of120 Fadama farmers and their location. One hundred and twenty non-Fadama farmers were drawn using the same technique for comparison.

  7. Interrelated factors influence of current stock market on pricing

    Directory of Open Access Journals (Sweden)

    Наталія Петрівна Мацелюх

    2015-03-01

    Full Text Available Impacts on market prices of securities are generalized. It is found that in the process of price determination and its implementation exist a system of interrelated factors of influence, which are divided into objective and subjective; internal and external; traditional and specific. It is proved that the impact of factors associated with risk pricing in financial assets

  8. Automation bias: empirical results assessing influencing factors.

    Science.gov (United States)

    Goddard, Kate; Roudsari, Abdul; Wyatt, Jeremy C

    2014-05-01

    To investigate the rate of automation bias - the propensity of people to over rely on automated advice and the factors associated with it. Tested factors were attitudinal - trust and confidence, non-attitudinal - decision support experience and clinical experience, and environmental - task difficulty. The paradigm of simulated decision support advice within a prescribing context was used. The study employed within participant before-after design, whereby 26 UK NHS General Practitioners were shown 20 hypothetical prescribing scenarios with prevalidated correct and incorrect answers - advice was incorrect in 6 scenarios. They were asked to prescribe for each case, followed by being shown simulated advice. Participants were then asked whether they wished to change their prescription, and the post-advice prescription was recorded. Rate of overall decision switching was captured. Automation bias was measured by negative consultations - correct to incorrect prescription switching. Participants changed prescriptions in 22.5% of scenarios. The pre-advice accuracy rate of the clinicians was 50.38%, which improved to 58.27% post-advice. The CDSS improved the decision accuracy in 13.1% of prescribing cases. The rate of automation bias, as measured by decision switches from correct pre-advice, to incorrect post-advice was 5.2% of all cases - a net improvement of 8%. More immediate factors such as trust in the specific CDSS, decision confidence, and task difficulty influenced rate of decision switching. Lower clinical experience was associated with more decision switching. Age, DSS experience and trust in CDSS generally were not significantly associated with decision switching. This study adds to the literature surrounding automation bias in terms of its potential frequency and influencing factors. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Factors influencing a problem-based learning implementation: A case study of IT courses

    Science.gov (United States)

    Darus, Norida Muhd; Mohd, Haslina; Baharom, Fauziah; Saip, Mohamed Ali; Puteh, Nurnasran; Marzuki @ Matt, Zaharin; Husain, Mohd Zabidin; Yasin, Azman

    2016-08-01

    IT students must be trained to work efficiently as teamwork. One of the techniques that can be used to train them is through Problem-Based Learning (PBL) approach. The PBL implementation can be influenced by various factors depending on the ultimate goal of the study. This study is focusing on the IT students' perception of the PBL implementation. The student's perception is important to ensure the successfulness of the PBL implementation. Therefore, it is important to identify the factors that might influence the implementation of PBL of IT courses. This study aims to identify some catalyst factors that may influence the PBL implementation of IT courses. The study involved three (3) main phases: identifying PBL implementation factors, constructing a PBL model, and PBL model validation using statistical analysis. Four main factors are identified: PBL Characteristics, PBL Course Assessment, PBL Practices, and PBL Perception. Based on these four factors, a PBL model is constructed. Then, based on the proposed PBL model, four hypotheses are formulated and analyzed to validate the model. All hypotheses are significantly acceptable. The result shows that the PBL Characteristics and PBL Course Assessment factors are significantly influenced the PBL Practices and indirectly influenced the Students' Perception of the PBL Implementation for IT courses. This PBL model can assist decision makers in enhancing the PBL teaching and learning strategy for IT courses. It is also can be tested to other courses in the future.

  10. A Survey of the Influencing Factors for International Academic Mobility of Chinese University Students

    Science.gov (United States)

    Cao, Chun; Zhu, Chang; Meng, Qian

    2016-01-01

    This research aims to understand the factors influencing international academic mobility within the Chinese higher education context. The inventory of University Students' Perceptions of Influencing Factors for International Academic Mobility was developed and tested to enquire about Chinese university students' perceptions of factors influencing…

  11. A study of the factors influencing school-going students considering medical careers.

    LENUS (Irish Health Repository)

    McHugh, S M

    2012-02-01

    INTRODUCTION: Obtaining a place in an Irish medical school is extremely competitive, a situation mirrored in many other countries. We aimed to determine the factors influencing school students in deciding to study medicine in university. We further determined what level of interest exists in pursuing a surgical career after completion of medical school. METHODS: The Royal College of Surgeons in Ireland hosts an annual "Introduction to Medicine" programme for senior school children. Attendees were surveyed using a Likert scale to examine the factors influencing the group in choosing to study medicine, and pursue surgery as their ultimate career choice. RESULTS: A total of 128 completed the survey, giving a response rate of 100%. The opportunity to help others was most the most influential factors cited by students (97%). Males were significantly more likely to have an interest in a career in surgery rather than medicine (p = 0.003), and ranked "financial reward" (p = 0.036) as a more significant factors in influencing career choice than did females. CONCLUSIONS: A clear understanding of these factors influencing our students in their career choices and a strategy of recruitment based on these is imperative in order to optimize recruitment of students most suited to working as doctors.

  12. ANALYSIS OF THE EXTERNAL FACTORS OF INFLUENCE ON INNOVATION ACTIVITY OF AN INDUSTRIAL ENTERPRISE

    Directory of Open Access Journals (Sweden)

    I. A. Salikov

    2014-01-01

    Full Text Available Summary. For successful functioning and development of the enterprise is a need to strive as possible deeper and more dynamic influence on parameters and objects OK-environmental management, primarily due to increase their innovation activity. Innovative activity of enterprises influenced by many factors. They can be classified on the factors of direct influence (micro and factors of indirect impacts (macro. Factors of direct impact of the influence on the pace and scale of development of the enterprise, on its effectiveness, because the whole spectrum of these factors acts as a limiter. Macro factors create the General conditions of existence of the enterprise in the external environment. To analyses these factors approach was used to SNW-analysis. As a result of analysis, factors of micro and macro-were classified on: stimulating, it minesweepers and dissuasive. Also studied were the degree of influence of these factors on the innovative activity of the enterprise. Reviewed rating factors hindering the development of innovation activity of industrial enterprise in Russia. In the result of which identified factors that hinder the development of innovative activity, and justified in the direction of overcoming them. It should be noted that the distinction between enabling and constraining factors is rather thin and conditional. So, the factors initially restraining innovation, at a certain point can be transformed into a stimulus for its development. Accounting for these factors, creation of necessary conditions and introduction of innovations in various aspects of the functioning of industrial enterprises will allow them to provide competitor-term benefits and sustainable development in a rapidly changing environment and the external environment.

  13. Genetic and environmental factors influencing the Placental Growth Factor (PGF) variation in two populations

    DEFF Research Database (Denmark)

    Sorice, Rossella; Ruggiero, Daniela; Nutile, Teresa

    2012-01-01

    . However, to date, no information is available regarding the genetics of PGF variability. Furthermore, even though the effect of environmental factors (e.g.: cigarette smoking) on angiogenesis has been explored, no data on the influence of these factors on PGF levels have been reported so far. Here we have......Placental Growth Factor (PGF) is a key molecule in angiogenesis. Several studies have revealed an important role of PGF primarily in pathological conditions (e.g.: ischaemia, tumour formation, cardiovascular diseases and inflammatory processes) suggesting its use as a potential therapeutic agent...

  14. Determinants of factors influencing technical efficiency of cocoa ...

    African Journals Online (AJOL)

    This study examined the factors influencing technical efficiency of cocoa production in Ondo State, Nigeria using a stochastic frontier production function. Using the random sampling technique, well-structured questionnaire were used to elicit information from 120 cocoa farmers in Ondo State, Nigeria. The mean technical ...

  15. Factors Influencing Prescribing Practices of Medical Practitioners in ...

    African Journals Online (AJOL)

    the currently used drugs, influence of pharmaceutical sales representatives and inadequate training and professional development [2,7]. Other factors include poor communication between health professional and patients regarding the basic information about the use of drugs. Most of the studies done in Tanzania on this ...

  16. Factors Influencing Household Solid Waste Management in Urban ...

    African Journals Online (AJOL)

    The main objective of this study was to determine factors that influence household solid waste management practices in urban Nyeri Municipality. Descriptive cross- sectional ... Results from the survey showed that 26.2% of households practiced correct methods of household solid waste management. The percentage of ...

  17. Factors Influencing Utilization of Modern Family Planning Services ...

    African Journals Online (AJOL)

    Factors Influencing Utilization of Modern Family Planning Services among Women of Child Bearing Age (15 - 49 years) in the University of Calabar Teaching Hospital, Calabar. ... Using accidental sampling technique, 150 women of childbearing age were selected to constitute the sample. Data were collected using a ...

  18. Hepatitus B virus infection : factors influencing the outcome

    NARCIS (Netherlands)

    J. van Hattum (Jan)

    1986-01-01

    textabstractThis study was designed to find correlations between the various courses of disease after hepatitis B virus (HBV) infection and factors that could conceivably have influenced the course of disease. The aim of the study was to find correlations between parameters of viral replication and

  19. Factors that influence attitudes and sexual behavior among ...

    African Journals Online (AJOL)

    This survey was carried out to assess attitudes and behaviour among youth within four constituencies in Oshana region, Namibia and to understand to how certain social and cultural factors inform attitudes and influence sexual behaviour among the population of young people surveyed. Using a structured questionnaire, ...

  20. The Influence of Psychological Factors in Meniere's Disease | Orji ...

    African Journals Online (AJOL)

    The Influence of Psychological Factors in Meniere's Disease. ... Annals of Medical and Health Sciences Research ... probably through disorders of the autonomic nervous system occasioned by the increased levels of stress‑related hormones.

  1. Socio-economic factors influencing marketing of non-timber forest ...

    African Journals Online (AJOL)

    Socio-economic factors influencing marketing of non-timber forest products in ... enhance skills for product transformation, build innovative storage facilities, and ... the process of domestication and integration in traditional land-use systems.

  2. Socio-Cultural Factors Influencing Consent For Research In Nigeria ...

    African Journals Online (AJOL)

    Socio-Cultural Factors Influencing Consent For Research In Nigeria: Lessons ... for Health Research Ethics in enforcing researchers' compliance with ethical standards in ... Genuine respect for human dignity requires deeper understanding of ...

  3. Safety of oxytetracycline (Terramycin TM-100F) administered in feed to hybrid striped bass, walleyes, and yellow perch

    Science.gov (United States)

    Gaikowski, M.P.; Wolf, J.C.; Schleis, S.M.; Gingerich, W.H.

    2003-01-01

    Oxytetracycline (Terramycin TM-100F, a medicated premix containing oxytetracycline at 220 g/kg) is approved in the United States to control certain systemic bacterial diseases of salmon and catfish when fed at a rate of 55-82.5 mg per kilogram of bodyweight per day for 10 d. Although oxytetracycline may also control certain systemic bacterial infections in coolwater or scaled warmwater fish, no safety data for such species are available. Our objective was to determine the safety of oxytetracycline administered in feed at nominal doses of 0, 82.5, 248, or 413 mg??kg-1??d-1 to yellow perch Perca flavescens and hybrid striped bass (striped bass Morone saxatilis x white bass M. chrysops) for 10 d and to walleye Sander vitreus (formerly Stizostedion vitreum) for 20 d. Yellow perch and hybrid striped bass consumed 50% to 100% of the diet, whereas walleye feed consumption was occasionally less than 50% of the diet. Feed or fecal material was present in the gastrointestinal tract of all necropsied walleyes except for one control fish. The single growth effect was that hybrid striped bass offered a nominal dose of 413 mg??kg-1??d-1 were significantly smaller than untreated controls. Oxytetracycline-related histopathological findings were limited to walleyes and were of low severity. The histopathological findings included decreased hematopoietic-lymphopoietic (H&L) tissue in the anterior kidneys, diffuse hyperplasia of the gill filament epithelium, and a decreased prevalence of fish with eosinophilic droplets in their renal tubular epithelial cells. Although the incidence of decreased H&L tissue tended to increase in proportion to oxytetracycline dose, this finding was statistically significant only for fish that received a nominal dose of 413 mg??kg-1??d-1. Given the pathogenicity of the types of bacteria that are controlled by oxytetracycline treatment and the long history of its use in major aquaculture species, the relative risk of the minor oxytetracycline

  4. Analysis of Spatial Pattern and Influencing Factors of E-Commerce

    Science.gov (United States)

    Zhang, Y.; Chen, J.; Zhang, S.

    2017-09-01

    This paper aims to study the relationship between e-commerce development and geographical characteristics using data of e-commerce, economy, Internet, express delivery and population from 2011 to 2015. Moran's I model and GWR model are applied to analyze the spatial pattern of E-commerce and its influencing factors. There is a growth trend of e-commerce from west to east, and it is obvious to see that e-commerce development has a space-time clustering, especially around the Yangtze River delta. The comprehensive factors caculated through PCA are described as fundamental social productivity, resident living standard and population sex structure. The first two factors have positive correlation with e-commerce, and the intensity of effect increases yearly. However, the influence of population sex structure on the E-commerce development is not significant. Our results suggest that the clustering of e-commerce has a downward trend and the impact of driving factors on e-commerce is observably distinct from year to year in space.

  5. Influencing factors of embryo rescue in seedless grape

    International Nuclear Information System (INIS)

    Guo, X.; Chen, W.; Liu, Z.; Li, K.

    2015-01-01

    In this study, we investigated the impact of inoculating stage, medium type and concentration of plant growth regulators on embryo rescue effectiveness by L25(5)6 orthogonal design using selfed ovules of Venus Seedless as the testing material. The main results were as follows. The most important factor influencing ovule germination was inoculating stage. Ovule germinating rate gradually increased as inoculating being postponed. The highest germinating rate appeared when inoculation was done 55d after flowering. Other influencing factors were IBA concentration, exogenous amino acid, 6-BA concentration, GA3 concentration and medium type in descending order. The best embryo rescue result was based on Nitsch medium including 1.0 mg/L IBA, 0.1 mg/L GA3, 0.7 mg /L 6-BA and 2.0 mmol/L glutamine using ovules inoculated 55d after flowering. The highest germinating rate reached 41.25%, and a batch of seedlings was also obtained. (author)

  6. Factors influencing physicians' knowledge sharing on web medical forums.

    Science.gov (United States)

    Lin, Tung Cheng; Lai, Ming Cheng; Yang, Shu Wen

    2016-09-01

    Web medical forums are relatively unique as knowledge-sharing platforms because physicians participate exclusively as knowledge contributors and not as knowledge recipients. Using the perspective of social exchange theory and considering both extrinsic and intrinsic motivations, this study aims to elicit the factors that significantly influence the willingness of physicians to share professional knowledge on web medical forums and develops a research model to explore the motivations that underlie physicians' knowledge-sharing attitudes. This model hypothesizes that constructs, including shared vision, reputation, altruism, and self-efficacy, positively influence these attitudes and, by extension, positively impact knowledge-sharing intention. A conventional sampling method and the direct recruitment of physicians at their outpatient clinic gathered valid data from a total of 164 physicians for analysis in the model. The empirical results support the validity of the proposed model and identified shared vision as the most significant factor of influence on knowledge-sharing attitudes, followed in descending order by knowledge-sharing self-efficacy, reputation, and altruism. © The Author(s) 2015.

  7. Extrinsic and Intrinsic Factors Influencing Employee Motivation: Lessons from AMREF Health Africa in Kenya

    Directory of Open Access Journals (Sweden)

    Stephen Morangi Nyambegera

    2016-10-01

    Full Text Available The purpose of the study was to determine the factors that influence employee motivation in Kenyan Organizations. The study was guided by the following research questions: (i what are the extrinsic factors that influence employee motivation in AMREF Health Africa in Kenya? (ii what intrinsic factors influence employee motivation in AMREF Health Africa in Kenya? A descriptive research design was adopted. Stratified random sampling technique was used to draw a sample size of 96 respondents. The data collection instrument was a structured questionnaire developed by the researchers.  A set of descriptive and correlation statistics were adopted for analysis. The study identified several intrinsic factors that influence employee motivation. These included employee achievements, recognition, work itself, responsibility and advancement, salary structure, the level to which the employees feel appreciated, and the employee perception of their jobs among other factors. The study further, established that the intrinsic factors that influence employee motivation include empowerment and autonomy, employees’ view of their work, organization trust, skill variety requirements among others. The study recommends that the organization should acknowledge and make use of a proper mix of extrinsic and intrinsic factors in their human resource management practices to ensure that employees are well motivated to perform their tasks.

  8. Factors influencing elderly women's mammography screening decisions: implications for counseling

    Directory of Open Access Journals (Sweden)

    Davis Roger B

    2007-11-01

    Full Text Available Abstract Background Although guidelines recommend that clinicians consider life expectancy before screening older women for breast cancer, many older women with limited life expectancies are screened. We aimed to identify factors important to mammography screening decisions among women aged 80 and older compared to women aged 65–79. Methods Telephone surveys of 107 women aged 80+ and 93 women aged 65–79 randomly selected from one academic primary care practice who were able to communicate in English (60% response rate. The survey addressed the following factors in regards to older women's mammography screening decisions: perceived importance of a history of breast disease, family history of breast cancer, doctor's recommendations, habit, reassurance, previous experience, mailed reminder cards, family/friend's recommendations or experience with breast cancer, age, health, and media. The survey also assessed older women's preferred role in decision making around mammography screening. Results Of the 200 women, 65.5% were non-Hispanic white and 82.8% were in good to excellent health. Most (81.3% had undergone mammography in the past 2 years. Regardless of age, older women ranked doctor's recommendations as the most important factor influencing their decision to get screened. Habit and reassurance were the next two highly ranked factors influencing older women to get screened. Among women who did not get screened, women aged 80 and older ranked age and doctor's counseling as the most influential factors and women aged 65–79 ranked a previous negative experience with mammography as the most important factor. There were no significant differences in preferred role in decision-making around mammography screening by age, however, most women in both age groups preferred to make the final decision on their own (46.6% of women aged 80+ and 50.5% of women aged 65–79. Conclusion While a doctor's recommendation is the most important factor influencing

  9. [Analysis on influencing factor of the complications of percutaneous dilational tracheotomy].

    Science.gov (United States)

    Zhai, Xiang; Zhang, Jinling; Hang, Wei; Wang, Ming; Shi, Zhan; Mi, Yue; Hu, Yunlei; Liu, Gang

    2015-01-01

    To Analyze the influence factors on the complications of percutaneous dilational tracheotomy. Between August 2008 and February 2014, there were 3 450 patients with the indications of tracheotomy accepted percutaneous dilational tracheostomy, mainly using percutaneous dilational and percutaneous guide wire forceps in these cases. Statistical analysis was performed by SPSS 19.0 software on postoperative complications, the possible influence factors including age, gender, etiology, preoperative hypoxia, obesity, preoperative pulmonary infection, state of consciousness, operation method, operation doctor and whether with tracheal intubation. Among 3 450 patients, there were 164 cases with intraoperative or postoperative complications, including postoperative bleeding in 74 cases (2.14%), subcutaneous emphysema in 54 cases (1.57%), wound infection in 16 cases (0.46%), pneumothorax in 6 cases (0.17%), mediastinal emphysema in 5 cases (0.14%), operation failed and change to conventional incision in 4 cases (0.12%), tracheoesophageal fistula in 2 cases (0.06%), death in 3 cases(0.09%).Obesity, etiology, preoperative hypoxia, preoperative pulmonary infection, state of consciousness and operation method were the main influence factors, with significant statistical difference (χ(2) value was 0.010, 0.000, 0.002, 0.000, 0.000, 0.000, all P Gender, age, operation doctor and whether there was the endotracheal intubation were not the main influence factors. There was no significant statistical difference (P > 0.05). Although percutaneous dilational tracheostomy is safe, but the complications can also happen. In order to reduce the complications, it is need to pay attention to the factors of obesity, etiology, preoperative hypoxia, preoperative pulmonary infection, state of consciousness and operation method.

  10. Influence of gender and other factors on medical student specialty interest.

    Science.gov (United States)

    Boyle, Veronica; Shulruf, Boaz; Poole, Phillippa

    2014-09-12

    Medical schools must select and educate to meet anticipated health needs. Factors influencing career choice include those of the student and their background as well as subsequent experience. Women have comprised over 50% of medical classes for over 20 years. This study describes gender patterns of current specialty interest among medical students at the University of Auckland, and models the predictive effect of gender compared to other career influencing factors. The study analysed career intention survey data from 711 graduating medical students (response rate, 79%) from 2006 to 2011. Interest level was highest for medicine, followed by subspecialty surgery, general practice and paediatrics. There were differences by gender for most specialties, but not for general practice. Women were more likely than men to be interested in Obstetrics and Gynaecology, Paediatrics, Geriatrics, Public Health or General Medicine, and less interested in Surgery, Anaesthesia, Emergency Medicine or post graduate study. Each specialty had a different pattern of influencing factors with the most important factor being the experience on a clinical attachment. Factors in career choice are complex and vary by gender and specialty. General practice levels of interest are too low for workforce needs. Predictive models need to be validated in longer term studies but may help guide selection and curriculum design.

  11. The Influence of Social Factors on Life Satisfaction in Old Age

    Directory of Open Access Journals (Sweden)

    Boris Miha Kaučič

    2016-12-01

    Full Text Available Research question (RQ: What is the connection between social factors and life satisfaction in old age? Purpose: The purpose of this research was to establish the influence of social factors on life satisfaction in old age. Method: The quantitative research method was used, a causal non-experimental method. As sampling data technique we used the technique of a survey questionnaire in ten statistical regions. For the analysis of causal effects and conditional associations we used the advanced statistical propensity score methods (Rubin, 2006. From the statistical set a simple random sample was chosen, we decided on proportionate stratification. For measuring life satisfaction we used Satisfaction with Life Scale (Diener, to which we added questions in order to study social factors. The research included 656 older adults aged 65 years and above, living in the home environment or in social care institutions. Results: Closely connected to life satisfaction in old age is the living conditions index (housing conditions, environment, financial situation, safety, whereas the lifestyle index (physical activity, nutrition, smoking, alcohol consumption is less closely connected. Discussion: Life satisfaction in old age is importantly influenced by social factors – suitable living conditions and less influenced by a healthy lifestyle, both of which allow for a quality life also in old age. Society: The research has an important influence on the society, as too little attention is being devoted to the phenomenon of ageing. By alerting the public we wish to contribute towards the detabuisation of ageing and ageism. For the stable healthcare system it is important that older adults remain healthy, independent and satisfied. Originality: The originality of the research is in the studying of social factor in the holistic model of satisfaction with life in the old age, which also includes physical, psychological and spiritual factors. Limitations

  12. Organizational factors influencing improvements in safety

    International Nuclear Information System (INIS)

    Marcus, A.; Nichols, M.L.; Olson, J.; Osborn, R.; Thurber, J.

    1992-01-01

    Research reported here seeks to identify the key organizational factors that influence safety-related performance indicators in nuclear power plants over time. It builds upon organizational factors identified in NUREG/CR-5437, and begins to develop a theory of safety-related performance and performance improvement based on economic and behavioral theories of the firm. Central to the theory are concepts of past performance, problem recognition, resource availability, resource allocation, and business strategies that focus attention. Variables which reflect those concepts are combined in statistical models and tested for their ability to explain scrams, safety system actuations, significant events, safety system failures, radiation exposure, and critical hours. Results show the performance indicators differ with respect to the sets of variables which serve as the best predictors of future performance, and past performance is the most consistent predictor of future performance

  13. Analysis of factors influencing adoption of okra production ...

    African Journals Online (AJOL)

    Socio-economic factors influencing adoption of okra technology packages in Enugu State, Nigeria was studied and analyzed in 2012. Purposive and multistage random sampling techniques were used in selecting communities, villages and Okra farmers. The sample size was 90 okra farmers (45Awgu and 45 Aninri Okra ...

  14. Factors Influencing Transient Poverty Among Agro-Pastoralists in ...

    African Journals Online (AJOL)

    Factors Influencing Transient Poverty Among Agro-Pastoralists in semi-arid areas of Kenya. ... The number of livelihood sources, education level of the household head, relief food, extension service and distance to the nearest markets were positively related to per capita daily income. A negative relationship was observed ...

  15. Factors Influencing the Outcomes in Extradural Haematoma Patients

    African Journals Online (AJOL)

    neurosurgical emergencies and are one of the most common causes of mortality and disability after traumatic brain injury. This study aimed at evaluating the current management and factors that influence outcome in patients treated for extradural hematoma in an African setting. Methods: A total of 224 consecutive patients ...

  16. Factors Influencing Consumers Intention for Online Grocery Shopping - A Proposed Framework

    Science.gov (United States)

    Pauzi, SFF; Thoo, AC; Tan, LC; Muharam, FM; Talib, NA

    2017-06-01

    Nowadays, Internet is one of the most popular platforms for people to do online shopping including grocery items. Many studies have been conducted to investigate the determinants of customer intentions for online grocery shopping. Till now, there is no consensus on what are the factors that actually influencing people to shop grocery items through Internet. This paper aims to explore the factors such as social influences, facilitating conditions, hedonic motivations, perceived risk and perceived trust that influence the consumer intention to purchase grocery online. Questionnaires will be the main instrument of the study and they will be distributed to target respondents using Internet survey. Respondents of the study will be selected using convenience sampling. After data collection, Statistical Package for the Social Sciences (SPSS) will be employed for data analysis. Overall, the result of the study is important to retailers to identify the important factors in increasing their customers’ intention to purchase grocery online.

  17. Factors that influence the relative use of multiple memory systems.

    Science.gov (United States)

    Packard, Mark G; Goodman, Jarid

    2013-11-01

    Neurobehavioral evidence supports the existence of at least two anatomically distinct "memory systems" in the mammalian brain that mediate dissociable types of learning and memory; a "cognitive" memory system dependent upon the hippocampus and a "stimulus-response/habit" memory system dependent upon the dorsolateral striatum. Several findings indicate that despite their anatomical and functional distinctiveness, hippocampal- and dorsolateral striatal-dependent memory systems may potentially interact and that, depending on the learning situation, this interaction may be cooperative or competitive. One approach to examining the neural mechanisms underlying these interactions is to consider how various factors influence the relative use of multiple memory systems. The present review examines several such factors, including information compatibility, temporal sequence of training, the visual sensory environment, reinforcement parameters, emotional arousal, and memory modulatory systems. Altering these parameters can lead to selective enhancements of either hippocampal-dependent or dorsolateral striatal-dependent memory, and bias animals toward the use of either cognitive or habit memory in dual-solution tasks that may be solved adequately with either memory system. In many learning situations, the influence of such experimental factors on the relative use of memory systems likely reflects a competitive interaction between the systems. Research examining how various factors influence the relative use of multiple memory systems may be a useful method for investigating how these systems interact with one another. Copyright © 2013 Wiley Periodicals, Inc.

  18. Leadership styles of Finnish nurse managers and factors influencing it.

    Science.gov (United States)

    Vesterinen, Soili; Isola, Arja; Paasivaara, Leena

    2009-05-01

    The purpose of the present study was to explore nurse managers' perceptions of their leadership styles and factors influencing it. It is a challenge for nurse managers to retain nurses in hospitals and to ensure a high quality of care in nursing practice. Leadership style is an important part of leadership. Knowledge concerning nurse managers' resonant and non-resonant leadership styles provides nurse managers with tools to reflect on their own leadership style. Open-ended, tape-recorded interviews were conducted with 13 nurse managers from five Finnish hospitals and two long-term care facilities. The data were analysed using qualitative content analysis. Five categories of leadership style were discerned: visionary, coaching, affiliate, democratic, commanding. Factors that influence leadership style were identified: earlier superiors, values, information, cooperation, employees and education. The results of this study show that Finnish nurse managers use both resonant and non-resonant leadership styles. The findings of this study show that nurse managers use a variety of leadership styles. The study demonstrates the importance of knowledge about leadership styles and factors influencing it among nurse managers providing future leadership and management education.

  19. Nuclear medicine - factors influencing the choice and use of radionuclides in diagnosis and therapy

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    This report addresses the many factors which influence the choice of the proper radiopharmaceutical drug product for the diagnosis or treatment of a specific disease or condition in a human subject. The Report examines the historical factors that influence the choice of radionuclides, the factors that influence the localization of radionuclides in tissues, the factors that influence the choice of instruments, and include an evaluation of the nuclear medicine procedures that could be selected and their clinical usefulness. In examining these factors the desirable characteristics of the radiopharmaceutical drug products of the measurement systems are identified. The methods of dose determination and the assumptions used in determination of dose are developed. There is also a section on radiation effects. A chapter on guidelines for procedures in nuclear medicine and some general and specific recommendations for protection of patients conclude the body of the text

  20. Factors influencing the provision of removable partial dentures by dentists in Ireland.

    Science.gov (United States)

    Allen, Finbarr

    2010-01-01

    Factors influencing clinical treatment of partially dentate patients are varied, and there is a need to identify factors influencing success in the provision of removable partial dentures. The aim of this study was to assess the attitudes of general dental practitioners (GDPs) in Ireland towards tooth replacement and use of RPDs, in partially dentate older adults. The sample frame was the Register of Dentists in Ireland; data were also collected from a sample of dentists practising under NHS regulations in Northern Ireland. Validated questionnaires were sent to all dentists on the Register of Dentists in the Republic of Ireland, and dentists working under NHS regulations registered with the Central Services Agency in Northern Ireland. Content of the questionnaire included details of the dentist themselves, their dental practice and the profile of partial denture provision. They were also asked to give their views on factors influencing the success or failure of an RPD, the process of providing RPDs and their attitudes to RPD provision. A total of 1,143 responses were received, a response rate of 45%. A mean number of 61 RPDs per annum were provided, with 75% of dentures provided being acrylic based. Respondents indicate their belief that cobalt-chromium based dentures had a longer prognosis than acrylic dentures, but less than half (46%) claim to design the frameworks themselves. Patients' attitudes are considered influential in the success of RPD provision, and their influence on appearance is considered the most important factor influencing success. The most important factors influencing failure are: the patient not requesting a denture; an RPD restoring unbounded saddles; and, lower RPDs. Although considered important, approximately 60% of the sample do not routinely organise follow-up appointments for patients provided with RPDs. The fee structures in the DTSS and DTBS are considered a barrier to quality in the provision of partial dentures.

  1. Factors influencing the provision of removable partial dentures by dentists in Ireland.

    LENUS (Irish Health Repository)

    Allen, Finbarr

    2011-03-15

    Factors influencing clinical treatment of partially dentate patients are varied, and there is a need to identify factors influencing success in the provision of removable partial dentures. The aim of this study was to assess the attitudes of general dental practitioners (GDPs) in Ireland towards tooth replacement and use of RPDs, in partially dentate older adults. The sample frame was the Register of Dentists in Ireland; data were also collected from a sample of dentists practising under NHS regulations in Northern Ireland. Validated questionnaires were sent to all dentists on the Register of Dentists in the Republic of Ireland, and dentists working under NHS regulations registered with the Central Services Agency in Northern Ireland. Content of the questionnaire included details of the dentist themselves, their dental practice and the profile of partial denture provision. They were also asked to give their views on factors influencing the success or failure of an RPD, the process of providing RPDs and their attitudes to RPD provision. A total of 1,143 responses were received, a response rate of 45%. A mean number of 61 RPDs per annum were provided, with 75% of dentures provided being acrylic based. Respondents indicate their belief that cobalt-chromium based dentures had a longer prognosis than acrylic dentures, but less than half (46%) claim to design the frameworks themselves. Patients\\' attitudes are considered influential in the success of RPD provision, and their influence on appearance is considered the most important factor influencing success. The most important factors influencing failure are: the patient not requesting a denture; an RPD restoring unbounded saddles; and, lower RPDs. Although considered important, approximately 60% of the sample do not routinely organise follow-up appointments for patients provided with RPDs. The fee structures in the DTSS and DTBS are considered a barrier to quality in the provision of partial dentures.

  2. Factors influencing the provision of removable partial dentures by dentists in Ireland.

    LENUS (Irish Health Repository)

    Allen, Finbarr

    2010-10-01

    Factors influencing clinical treatment of partially dentate patients are varied, and there is a need to identify factors influencing success in the provision of removable partial dentures. The aim of this study was to assess the attitudes of general dental practitioners (GDPs) in Ireland towards tooth replacement and use of RPDs, in partially dentate older adults. The sample frame was the Register of Dentists in Ireland; data were also collected from a sample of dentists practising under NHS regulations in Northern Ireland. Validated questionnaires were sent to all dentists on the Register of Dentists in the Republic of Ireland, and dentists working under NHS regulations registered with the Central Services Agency in Northern Ireland. Content of the questionnaire included details of the dentist themselves, their dental practice and the profile of partial denture provision. They were also asked to give their views on factors influencing the success or failure of an RPD, the process of providing RPDs and their attitudes to RPD provision. A total of 1,143 responses were received, a response rate of 45%. A mean number of 61 RPDs per annum were provided, with 75% of dentures provided being acrylic based. Respondents indicate their belief that cobalt-chromium based dentures had a longer prognosis than acrylic dentures, but less than half (46%) claim to design the frameworks themselves. Patients\\' attitudes are considered influential in the success of RPD provision, and their influence on appearance is considered the most important factor influencing success. The most important factors influencing failure are: the patient not requesting a denture; an RPD restoring unbounded saddles; and, lower RPDs. Although considered important, approximately 60% of the sample do not routinely organise follow-up appointments for patients provided with RPDs. The fee structures in the DTSS and DTBS are considered a barrier to quality in the provision of partial dentures.

  3. Studies on influence of environmental factors on concentration on concentration of radionuclides

    International Nuclear Information System (INIS)

    Anon.

    1974-01-01

    Environmental factors which seemed to influence the concentration of radionuclides to marine organisms including illumination, water temperature, coexisting stable elements, salt concentration, suspended matters in sea water and residue were studied. The influence of illumination was examined by algae using 137 Cs, 60 Co, 85 Sr, and 106 Ru as tracers, within 24 hours of illumination. The concentration of 137 Cs and 60 Co revealed remarkable increase of uptake in accordance with increasing illumination intensity, and 24 hours illumination showed 2 times concentration of that by 4 hours'. 85 Sr and 106 Ru showed no effect of illumination, and suggested their concentration was depending on adsorption to the surface. As for water temperature, the concentration factor of 65 Zn, 137 Cs obtained from fishes and shells by 22 0 C breeding was 2 times of that by 12 0 C breeding. Concerning the influence of coexisting stable elements, fishes and shells were examined by 54 Mn, 60 Co, and 65 Zn as tracers. When the stable elements concentration in sea water became 10 times the normal, concentration factor depending on adsorption and metabolism became respective one tenth and one second of the normal value. The influence of salt concentration was examined using 85 Sr, 65 Zn, and 137 Cs, and revealed that 28 to 40 per cent changes of salt level gave slight influence on concentration factor. In order to study the influence of suspended matters and quality of residue, 3 kinds of 106 Ru complex species were added. Concentration factor of Hijiki (Hijikia fusiforme) showed no remarkable difference between breeding in filtrated and non-filtrated sea water. However, clams living in the sand should be taken care of the concentration by the residue in the sea bottom. (Kanao, N.)

  4. Factors influencing acceptance of technology for aging in place: a systematic review.

    NARCIS (Netherlands)

    Peek, S.T.M.; Wouters, E.J.M.; Hoof, J. van; Luijkx, K.G.; Boeije, H.R.; Vrijhoef, H.J.M.

    2014-01-01

    Purpose: To provide an overview of factors influencing the acceptance of electronic technologies that support aging in place by community-dwelling older adults. Since technology acceptance factors fluctuate over time, a distinction was made between factors in the pre-implementation stage and factors

  5. Factors influencing acceptance of technology for aging in place : A systematic review

    NARCIS (Netherlands)

    Peek, S.T.M.; Wouters, E.J.M.; van Hoof, J.; Luijkx, K.G.; Boeije, H.R.; Vrijhoef, H.J.M.

    2014-01-01

    Purpose To provide an overview of factors influencing the acceptance of electronic technologies that support aging in place by community-dwelling older adults. Since technology acceptance factors fluctuate over time, a distinction was made between factors in the pre-implementation stage and factors

  6. An exploration study on factors influencing Iranian food industry

    Directory of Open Access Journals (Sweden)

    Arash Hosseinzadeh

    2013-05-01

    Full Text Available The proposed study of this paper present an empirical investigation to detect important factors impacting on food market using factor analysis. The proposed study designed a questionnaire, distributed among 207 customers who were regular customers of two food chains in city of Tehran, Iran named Shahrvand and Hyperstar. The results of our survey indicate that six major factors including brand loyalty, physical characteristics, pricing effects, performance characteristics, brand relationship and brand position influence food industry, significantly. In terms of the first factor, brand loyalty, “Trust”, “Packaging design characteristics”, “Competitive pricing strategy”, “Stability in quality”, “External relationships” and “Meeting expectations” are important factors in different categories.

  7. Factors influencing the career success of professional and business women in South Africa

    OpenAIRE

    Marianne Doubell; Miemie Struwig

    2014-01-01

    This article reports on an empirical study that investigated factors influencing women’s career success. Statistics relating to the field of women in management indicate that, worldwide, women are underrepresented in executive and decision-making positions. Women face unique challenges in their career pursuit that may prevent them from moving up to executive positions. A framework to investigate the factors influencing career success indicates that factors such as demographics, personality, c...

  8. Factors influencing energy efficiency investments in existing Swedish residential buildings

    International Nuclear Information System (INIS)

    Nair, Gireesh; Gustavsson, Leif; Mahapatra, Krushna

    2010-01-01

    We used the data from a survey conducted in 2008 of 3,000 owners of detached houses to analyse the factors that influence the adoption of investment measures to improve the energy efficiency of their buildings. For the majority of Swedish homeowners, it was important to reduce their household energy use, and most of them undertook no-cost measures as compared to investment measures. Personal attributes such as income, education, age and contextual factors, including age of the house, thermal discomfort, past investment, and perceived energy cost, influence homeowners' preference for a particular type of energy efficiency measure. The implications for promoting the implementation of energy efficiency investment measures are discussed.

  9. Assessment of the factors with significant influence on safety culture

    International Nuclear Information System (INIS)

    Farcasiu, M.; Nitoi, M.

    2013-01-01

    In this paper, a qualitative and a quantitative evaluation of the factors with significant impact on safety culture were performed. These techniques were established and applied in accordance with IAEA standards. In order to show the applicability and opportunity of the methodology a specific case study was prepared: safety culture evaluation for INR Pitesti. The qualitative evaluation was performed using specific developed questionnaires. Through analysis of the completed questionnaires was established the development stage of safety culture at INR. The quantitative evaluation was performed using a guide to rate the influence factors. For each factor was identified the influence (negative or positive) and ranking score was estimated using scoring criteria. The results have emphasized safety culture stages. The paper demonstrates the fact that using both quantitative and qualitative assessment techniques, a practical value of the safety culture concept is given. (authors)

  10. Influence Factor of Tertiary Students’ Employability Awareness Adjust Industry 4.0

    Directory of Open Access Journals (Sweden)

    Chun-Mei Chou

    2017-09-01

    Full Text Available This study aims to analyze the correlation (N=621 among tertiary students’ career planning, erecruiting adoption acceptance, and employability awareness in Taiwan. Tertiary students’ perceived career planning includes four factors, namely, self-appraisal, job expectancy, goal selection, and problem solving. E-recruiting adoption acceptance includes four factors, namely, playfulness, ease of use, effectiveness, and usefulness. Employability awareness includes four factors, namely, personal adaptability, employability ambition, career identity, and labour market. Participants responded to a 5-point Likert-type scale for each factor. Analysis was conducted using the structural equation modeling (SEM, and a good model fit was found for both the measurement and structural models. Research findings demonstrate that tertiary students’ career planning significantly and directly influences employability awareness. Career planning significantly and indirectly influences employability awareness by e-recruiting adoption acceptance. Tertiary students’ career planning and e-recruiting adoption acceptance fit the influence model and empirical data of employability awareness. Implications of this study, including the value of student self-assessment of their skills and utility of the e-recruiting to underpin personal career development planning and inform graduate recruitment processes, are discussed and recommendations made.

  11. What Factors Influence Vietnamese Students' Choice of University?

    Science.gov (United States)

    Dao, Mai Thi Ngoc; Thorpe, Anthony

    2015-01-01

    Purpose: The purpose of this paper is to report the factors that influence Vietnamese students' choice of university in a little researched context where the effects of globalization and education reform are changing higher education. Design/methodology/approach: A quantitative survey was completed by 1,124 current or recently completed university…

  12. Activity limitations and factors influencing functional outcome of ...

    African Journals Online (AJOL)

    EB

    2013-09-03

    Sep 3, 2013 ... life and satisfaction with life1,22. A recent study conducted among community dwelling stroke survivors found functional ability and independence to be the strongest predictor of, and were responsible for the greatest variance on participation22. For determining the factors influencing outcome with the use ...

  13. The Evolution of Early-Stage Entrepreneurial Activity Influencing Factors in Romania

    Directory of Open Access Journals (Sweden)

    Tünde Petra PETRU

    2010-07-01

    Full Text Available The aim of the article is to analyze the main influencing factors of the probability of becoming an early-stage entrepreneur in Romania. The analyzed factors are: gender, age, education, household income, work status, network, opportunity perception, perception regarding the trust in own entrepreneurial skills, perception on the society’s appreciation regarding the principle of equality in life standard, perception on the society’s appreciation regarding the entrepreneurial career, perception on the proper promotion of entrepreneurial successes by mass media. We estimate a logit model for each year of the 2007-2009 period and we study the main influencing perceptional and sociodemographic factors, based on the Global Entrepreneurship Monitor (GEM Adult Population Survey database for Romania.

  14. Polychlorinated biphenyls in adult black bass and yellow perch were not associated with their reproductive success in the upper Hudson River, New York, USA.

    Science.gov (United States)

    Maceina, Michael J; Sammons, Steven M

    2013-07-01

    Although production and use of polychlorinated biphenyls (PCBs) ceased nearly 35 yr ago, questions still remain concerning the potential chronic effects these compounds may have on wild fish, including their reproductive success. In the upper Hudson River, New York, USA, fish were exposed to PCBs primarily from 2 manufacturing plants located approximately 320 km upstream of New York City, New York, from the 1940s to 1977. The authors collected yellow perch (Perca flavescens), smallmouth bass (Micropterus dolomieu), and largemouth bass (M. salmoides) using electrofishing, measured PCBs in these adults, and estimated abundance and size of their offspring at age 1 yr (age-1 fish). Fish were collected annually from 2004 to 2009 from 1 control site upstream of the PCB discharge sites and from 2 sites downstream from where PCBs were released. These sites (pools) are separated by a series of dams, locks, and canals. Muscle tissue wet weight PCB and lipid-based PCB concentrations in adults in the 2 PCB exposure pools averaged approximately 1 to 3 µg/g and 100 to 500 µg/g, respectively. Age-1 abundances were not related to adult PCB concentrations but were inversely related to river flow. Size of age-1 fish was slightly greater at the PCB-exposure sites. Levels of PCBs in yellow perch, largemouth bass, and smallmouth bass in the upper Hudson River did not impair or reduce recruitment or reproductive success. Copyright © 2013 SETAC.

  15. Factors influencing economic performance of the South Moravian Region

    Directory of Open Access Journals (Sweden)

    Iva Živělová

    2011-01-01

    Full Text Available The paper deals with selected factors influencing economic performance of the South Moravian Region in the years 2003–2009. The economic performance of the region is evaluated by means of a contribution to the Gross Domestic Product of the Czech Republic. Considering the fact that the level of economic activity depends on the exploitation rate of production factors in the considered region, both development of soil exploitation rate and development of labour market indicators correlated with working force utilization are analysed, a number of employed adults and registered unemployment are taken into consideration. Attention is paid to the economic activity rate. The formation of the Gross Fixed Capital, which an assumption of favourable economic performance, and development of Gross Added Value are evaluated.All the regions nowadays fumble with the negative impacts of the economic crisis. According to the analysis of the economic performance of the South Moravian Region and the analysis of the factors influencing this performance, it could be stated, that the development of the South Moravian Region could be evaluated quite positively.

  16. Psychological Factors Influencing Life Satisfaction of Undergraduates

    OpenAIRE

    Ajayi, Olubukola; Adewumi, Bukunmi

    2017-01-01

    This study was designed to assess the psychological factors influencing life satisfaction of undergraduates. The instruments used were Perceived Stress Scale (PSS), Wong and Law Emotional Intelligence Scale (WLEIS), Rosenberge Self-esteem Scale (RSS), and Satisfaction with Life Scale (SWLS). A total number of 190 participants were purposively selected across various faculties in Ekiti State University. Four hypotheses were tested using Independent t-test to find the effects of perceived stres...

  17. Factors influencing primary health care professionals' physical activity promotion behaviors: a systematic review.

    Science.gov (United States)

    Huijg, Johanna M; Gebhardt, Winifred A; Verheijden, Marieke W; van der Zouwe, Nicolette; de Vries, Juriena D; Middelkoop, Barend J C; Crone, Mathilde R

    2015-02-01

    Despite the promising findings related to the efficacy of interventions aimed at promoting physical activity (PA) in primary health care (PHC), the translation of these interventions to PHC practice does not always happen as desired. To help understand why efficacious PHC-based PA interventions are not effectively translated to practice, this study systematically reviewed the literature on factors influencing PHC professionals' PA promotion practices. Literature searches were conducted in Web of Science, PubMed, and PsycINFO for peer-reviewed articles published in English from 1990 onwards. Studies were included that met the following criteria: (1) involving PHC-based PA interventions, and (2) reporting factors influencing PHC professionals' PA promotion behaviors. Two researchers independently screened studies and extracted data. A narrative synthesis using thematic analysis was conducted to identify factors. Of the 4,469 identified articles, 59 were included in the review. Factors were identified by qualitative methods, barrier/facilitator ratings, and the examination of the relationship between factors and PA promotion, and the effectiveness of introduction strategies. Many factors related to the development, delivery, and effects of the innovation, the sociopolitical and organizational culture, resources, and support, patient and PHC professional characteristics, and innovation strategies were identified as potential influences on PHC professionals' PA promotion practices. However, the lack of evidence on the relationship between factors and PA promotion indicated insufficient evidence on PA promotion determinants. This extensive overview of potential factors can inform intervention developers and implementers on which factors may play a role when introducing PA interventions in PHC. Future research should further investigate relationships between factors and PA promotion, which should be guided by qualitative in-depth knowledge on influencing factors.

  18. Factors influencing the career success of professional and business women in South Africa

    Directory of Open Access Journals (Sweden)

    Marianne Doubell

    2014-11-01

    Full Text Available This article reports on an empirical study that investigated factors influencing women’s career success. Statistics relating to the field of women in management indicate that, worldwide, women are underrepresented in executive and decision-making positions. Women face unique challenges in their career pursuit that may prevent them from moving up to executive positions. A framework to investigate the factors influencing career success indicates that factors such as demographics, personality, culture, barriers, external and internal support impact on the career success of women. This study surveyed a sample of 301 professional and business women in South Africa. The results of the empirical survey showed that there are statistical significant relationships between groups of women based on their demographics and their perceptions of the factors that influence their career success.

  19. An exploration study on detecting important factors influencing brand loyalty in retail stores

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2014-01-01

    Full Text Available Brand loyalty is one of the most important factors influencing on the success of retail stores. Many retail stores in the field of sport shoes in city of Tehran, Iran are facing tight competition and there seems to be that only stores with loyal customers could survive. In this paper, we present an exploration study to find out important factors influencing retail stores selling one of well-known sport shows such as Adidas, Nike, etc. in city of Tehran, Iran. The proposed study designs a questionnaire in Likert scale and distributes among 265 regular customers of these stores and analyze them using factor analysis. The results indicate that there were four important factors influencing customer loyalty including brand identification, brand promotion, brand loyalty and characterization of stores.

  20. Assessment of the prevalence and factors influencing adherence to ...

    African Journals Online (AJOL)

    admin

    adherence to exclusive breast feeding among HIV positive ... Despite its benefits, the practice of EBF among HIV positive mothers is low in Ethiopia. Objective: This study is intended to assess factors influencing adherence to exclusively breast ...

  1. [Factors influencing self-perception of overweight people].

    Science.gov (United States)

    Makara-Studzińska, Marta; Podstawka, Danuta; Goclon, Karolina

    2013-11-01

    Shaping of self-perception is among others influenced by physical, interpersonal, emotional, and cultural factors. In self-perception of overweight people an important role is played by interpersonal factors, which include the opinions of others and the relationship with the surrounding. The evaluation of the body image is also affect by sociocultural factors including the media, which create an unrealistic and impossible to achieve ideal of beauty. Contemporary ideal of beauty, where a slim figure is dominant, more frequently contributes to the occurrence of discrimination and stigmatization of overweight people. This phenomenon causes negative self-perception leading to the occurrence of such emotional problems as low self-esteem, lack of confidence, depression and anxiety disorders. Overweight children and adolescents are also frequently stigmatized and discriminated because of their body weight, which results in the development of a negative body image that may lead to low self-esteem and symptoms of depression.

  2. Factors Influencing Patronage Of Medical Tourism In Metropolitan Lagos Nigeria

    Directory of Open Access Journals (Sweden)

    Omisore

    2015-08-01

    Full Text Available Since medical tourism attract patient from various origin to seek medical services at different destinations it is paramount to consider the factors that motivate patrons decision on medical tourism. Hence this study assesses the factors influencing patronage of medical tourism in Lagos metropolis Nigeria. Lagos State is situated in the southwestern corner of Nigeria it lies within Latitudes 62N to 64N of the Equator and Longitudes 245E to 420E of the Greenwich meridian. Metropolitan Lagos is a statistical division and not an administrative unit it extends over 16 of the 20 LGAs of Lagos State it contains 88 of the population of Lagos State and includes semi-rural areas. Data were collected from primary source. Primary data collection was carried out through the use of structured questionnaire. Systematic sampling technique was employed to select 15 specialized private hospitals and 14 Public hospitals in the study area resulting to a sample size of 29 hospitals. Ten 10 patrons were contacted in each of the selected hospitals consequently 290 patrons were sampled. The study revealed three factors influencing patronage of medical tourism in the study area to be service related economic and facilities. These were further established by factor analysis result which combine service related economic factor as factor one with 29.5 variance explained and Eigen value of 5.605 Facility factor as factor two with 28.6 variance explained and Eigen value of 5.435 Service related factor as factor three with 14.7 variance explained and Eigen value of 2.788 and Economic factor as factor four with 9.2 variance explained and Eigen value of 1.754. The relevant authority in charge of health facilities in the study area would have to employ adequate manpower in-terms of doctors and other healthcare personnel across the public hospital while also regulating the scale of charges of the registered private hospitals in the study area. There is need to improve upon the

  3. Factors influencing career decisions in internal medicine.

    Science.gov (United States)

    Macdonald, C; Cawood, T

    2012-08-01

    Numerous factors influence career decisions for internal medicine trainees and Fellows. There is a perception that a greater emphasis is placed on work-family balance by younger physicians. To determine the characteristics of the modern internal medicine workforce and ascertain whether job flexibility is important to career decision-making. We hypothesised that factors which reflect flexibility would be highly influential in decision-making, especially for women and those with young children. A questionnaire was mailed to 250 New Zealand internal medicine trainees and Fellows. It focused on factors, including job flexibility, interest and collegial support, and included demographic details which were primarily aimed at ascertaining family responsibilities. Response rate was 54%. The majority of female physicians are the main person responsible for their children (62%), and the majority of their partners work full-time (80%). This contrasts with male physicians, of whom only 4% are the main person responsible for their children. Flexibility was found to be more influential in women, those with young children, trainees and those working in outpatient-based subspecialties. However, contrary to our original hypothesis, flexibility was not reported to be highly influential in any group, with career choice being most influenced by interest and enjoyment, intellectual challenge and variety within the job. It is hoped that results will inform employers and those involved with training to enable them to better cater for the needs of the workforce and also encourage trainees to consider future family commitments when making career decisions. © 2012 The Authors. Internal Medicine Journal © 2012 Royal Australasian College of Physicians.

  4. Factor Analysis on the Factors that Influencing Rural Environmental Pollution in the Hilly Area of Sichuan Province,China

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    By using factor analysis method and establishing analysis indicator system from four aspects including crop production,poultry farming,rural life and township enterprises,the difference,features,and types of factors influencing the rural environmental pollution in the hilly area in Sichuan Province,China.Results prove that the major factor influencing rural environmental pollution in the study area is livestock and poultry breeding,flowed by crop planting,rural life,and township enterprises.Hence future pollution prevention and control should set about from livestock and poultry breeding.Meanwhile,attention should be paid to the prevention and control of rural environmental pollution caused by rural life and township enterprise production.

  5. The influencing factors on place attachment in neighborhood of Kampung Melayu

    Science.gov (United States)

    Lestari, W. M.; Sumabrata, J.

    2018-03-01

    Place attachment on neighborhood differs according to place characteristics and person characteristics. By dividing the research area of Kelurahan Kampung Melayu into flood area and non-flood area, this research aims at analyzing place attachment on neighborhood and analyzing factors influencing the place attachment. This research using quantitative approach using Structural Equation Modeling (SEM). Self-administered questionnaires using likert scale were distributed randomly to 400 residents. Result of the research shows that residents tend to have place attachment to their neighborhood. Factors influencing place attachment on residents born in the neighborhood with length of stay 10 years or longer and having house are family factor for residents living in non-flood area and physical factor as well as social factor for residents in flood area. This research concludes that place attachment on neighborhood is formed because dimension of place is interpreted not merely physically but also socially, namely the existence of family ties and social relationship with people in the neighborhood.

  6. Factors Influencing Learning Environments in an Integrated Experiential Program

    Science.gov (United States)

    Koci, Peter

    The research conducted for this dissertation examined the learning environment of a specific high school program that delivered the explicit curriculum through an integrated experiential manner, which utilized field and outdoor experiences. The program ran over one semester (five months) and it integrated the grade 10 British Columbian curriculum in five subjects. A mixed methods approach was employed to identify the students' perceptions and provide richer descriptions of their experiences related to their unique learning environment. Quantitative instruments were used to assess changes in students' perspectives of their learning environment, as well as other supporting factors including students' mindfulness, and behaviours towards the environment. Qualitative data collection included observations, open-ended questions, and impromptu interviews with the teacher. The qualitative data describe the factors and processes that influenced the learning environment and give a richer, deeper interpretation which complements the quantitative findings. The research results showed positive scores on all the quantitative measures conducted, and the qualitative data provided further insight into descriptions of learning environment constructs that the students perceived as most important. A major finding was that the group cohesion measure was perceived by students as the most important attribute of their preferred learning environment. A flow chart was developed to help the researcher conceptualize how the learning environment, learning process, and outcomes relate to one another in the studied program. This research attempts to explain through the consideration of this case study: how learning environments can influence behavioural change and how an interconnectedness among several factors in the learning process is influenced by the type of learning environment facilitated. Considerably more research is needed in this area to understand fully the complexity learning

  7. Factors influencing perceived sustainability of Dutch community health programs.

    Science.gov (United States)

    Vermeer, A J M; Van Assema, P; Hesdahl, B; Harting, J; De Vries, N K

    2015-09-01

    We assessed the perceived sustainability of community health programs organized by local intersectoral coalitions, as well as the factors that collaborating partners think might influence sustainability. Semi-structured interviews were conducted among 31 collaborating partners of 5 community health programs in deprived neighborhoods in the southern part of the Netherlands. The interview guide was based on a conceptual framework that includes factors related to the context, the leading organization, leadership, the coalition, collaborating partners, interventions and outcomes. Interviews were recorded, transcribed and content analyzed using NVivo 8.0. Participants in each of the programs varied in their perceptions of the sustainability of the program, but those people collaborating in pre-existing neighborhood structures expressed relatively high faith in their continuation. The participating citizens in particular believed that these structures would continue to address the health of the community in the future. We found factors from all categories of the conceptual framework that were perceived to influence sustainability. The program leaders appeared to be crucial to the programs, as they were frequently mentioned in close interaction with other factors. Program leaders should use a motivating and supportive leadership style and should act as 'program champions'. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Determination of the Main Influencing Factors on Road Fatalities Using an Integrated Neuro-Fuzzy Algorithm

    Directory of Open Access Journals (Sweden)

    Amir Masoud Rahimi

    Full Text Available Abstract This paper proposed an integrated algorithm of neuro-fuzzy techniques to examine the complex impact of socio-technical influencing factors on road fatalities. The proposed algorithm could handle complexity, non-linearity and fuzziness in the modeling environment due to its mechanism. The Neuro-fuzzy algorithm for determination of the potential influencing factors on road fatalities consisted of two phases. In the first phase, intelligent techniques are compared for their improved accuracy in predicting fatality rate with respect to some socio-technical influencing factors. Then in the second phase, sensitivity analysis is performed to calculate the pure effect on fatality rate of the potential influencing factors. The applicability and usefulness of the proposed algorithm is illustrated using the data in Iran provincial road transportation systems in the time period 2012-2014. Results show that road design improvement, number of trips, and number of passengers are the most influencing factors on provincial road fatality rate.

  9. Factors influencing medical students in pursuing a career in surgery ...

    African Journals Online (AJOL)

    Background: Many factors play a role in the decision of a medical student to pursue a career in surgery. With a decline in numbers of applications into surgical programmes seen globally, the aim of this study was to determine the factors that influence medical students in pursuing a career in surgery. Methods: A descriptive ...

  10. Factors that Influence Students' Decision to Dropout of Online Courses

    Science.gov (United States)

    Willging, Pedro A.; Johnson, Scott D.

    2009-01-01

    Although there are many reasons why students dropout of college courses, those reasons may be unique for students who are enrolled in an online program. Issues of isolation, disconnectedness, and technological problems may be factors that influence a student to leave a course. To understand these factors, an online survey was developed to collect…

  11. Factors Influencing the Reliability of the Glasgow Coma Scale: A Systematic Review.

    Science.gov (United States)

    Reith, Florence Cm; Synnot, Anneliese; van den Brande, Ruben; Gruen, Russell L; Maas, Andrew Ir

    2017-06-01

    The Glasgow Coma Scale (GCS) characterizes patients with diminished consciousness. In a recent systematic review, we found overall adequate reliability across different clinical settings, but reliability estimates varied considerably between studies, and methodological quality of studies was overall poor. Identifying and understanding factors that can affect its reliability is important, in order to promote high standards for clinical use of the GCS. The aim of this systematic review was to identify factors that influence reliability and to provide an evidence base for promoting consistent and reliable application of the GCS. A comprehensive literature search was undertaken in MEDLINE, EMBASE, and CINAHL from 1974 to July 2016. Studies assessing the reliability of the GCS in adults or describing any factor that influences reliability were included. Two reviewers independently screened citations, selected full texts, and undertook data extraction and critical appraisal. Methodological quality of studies was evaluated with the consensus-based standards for the selection of health measurement instruments checklist. Data were synthesized narratively and presented in tables. Forty-one studies were included for analysis. Factors identified that may influence reliability are education and training, the level of consciousness, and type of stimuli used. Conflicting results were found for experience of the observer, the pathology causing the reduced consciousness, and intubation/sedation. No clear influence was found for the professional background of observers. Reliability of the GCS is influenced by multiple factors and as such is context dependent. This review points to the potential for improvement from training and education and standardization of assessment methods, for which recommendations are presented. Copyright © 2017 by the Congress of Neurological Surgeons.

  12. Succesful Lean Manufacturing Implementation: Internal Key Influencing Factors

    Science.gov (United States)

    Virginia, Iuga; Claudiu, Kifor

    2015-09-01

    Manufacturing sectors and companies all over the world are successfully implementing lean principles within their processes. Nowadays, lean has become an indispensable part of global players. Companies worldwide need to be aware of multiple factors which weigh heavily on the success or failure of lean implementation. This paper focuses on giving a brief and structured overview over the fundamental organizational factors which play a substantial role for the lean manufacturing (LM) implementation process. The study below focuses on internal factors which are indispensable for a successful LM implementation within organizations. It is imperative that these internal factors are known, recognized and taken into consideration during the whole LM implementation process. Ignoring their influence on the process's implementation may lead to endangering the expected results or to making the process more difficult which could result in much higher human resource consumption.

  13. An exploration study to detect important factors influencing insurance firms

    OpenAIRE

    Farzaneh Soleimani; Fattaneh Alizadeh Meshkani; Abdullah Naami

    2013-01-01

    The recent trend on competition among insurance firms has increased motivation to look for important factors influencing this industry. In this paper, we present an empirical investigation to find important factors shaping this industry. The proposed study designs a questionnaire in Likert scale and, using principal component analysis, detects important factors on the success of this industry. Cronbach alpha is calculated as 0.849, and Kaiser-Meyer-Olkin and Bartlett's Test are calculated as ...

  14. ANALYSIS OF SPATIAL PATTERN AND INFLUENCING FACTORS OF E-COMMERCE

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2017-09-01

    Full Text Available This paper aims to study the relationship between e-commerce development and geographical characteristics using data of e-commerce, economy, Internet, express delivery and population from 2011 to 2015. Moran’s I model and GWR model are applied to analyze the spatial pattern of E-commerce and its influencing factors. There is a growth trend of e-commerce from west to east, and it is obvious to see that e-commerce development has a space-time clustering, especially around the Yangtze River delta. The comprehensive factors caculated through PCA are described as fundamental social productivity, resident living standard and population sex structure. The first two factors have positive correlation with e-commerce, and the intensity of effect increases yearly. However, the influence of population sex structure on the E-commerce development is not significant. Our results suggest that the clustering of e-commerce has a downward trend and the impact of driving factors on e-commerce is observably distinct from year to year in space.

  15. Factors that influencing the usage of global distribution system

    Science.gov (United States)

    Budiasa, I. M.; Suparta, I. K.; Nadra, N. M.

    2018-01-01

    The advancement of Tourism is supported by Information and Communication Technology (ICT) innovation and changes. The use of GDS (Global Distribution System) i.e. Amadeus, Galileo, Sabre, and Worldspan in the tourism industry can increase the availability, frequency and speed of communication among the companies in providing services to potential tourists. This research is to investigate the factors that influence the actual use of GDS in the tourism industry especially travel agents, airlines and hotels in Bali. This research employed a mixed method of quantitative and qualitative approaches. Field surveys were conducted and 80 valid questionnaires were received and analyzed by using SPSS 17.0; descriptive, correlation, factor analysis and regression tests were conducted. The variables used are Perceived Ease of Use and Perceived Usefulness (Technology Acceptance Model); Awareness, Perceived Risk and Communication Channels are examined. This research revealed that Perceived Ease of Use, Perceived Usefulness, Awareness, and Communication Channels influence the Behavioural intention to use GDS, whereas Perceived Risk were found not significant influence the use of GDS. These findings enable travel agent, airline and hotel companies to make provision decision with respect to the actual use of GDS.

  16. Factors influencing purchase intention towards consumer-to-consumer e-commerce

    Directory of Open Access Journals (Sweden)

    Muhammad Dachyar

    2017-11-01

    Full Text Available Purpose: This study explores factors that influence consumer’s purchase intention at three consumer-to-consumer (C2C e-commerce companies in Indonesia. Design/methodology/approach: 5 Expert opinions are used to determine the indicators of each factor and the Structural Equation Modelling (SEM method is used to analyze the empirical data of  400 respondents for each company. Findings: It is found different significant factors that influence customer’s purchase intention in each company. Trust and risk are found to be significantly effect purchase intention in Company A. Meanwhile, the other two companies, perceived usefulness proved to be significant in Company B and benefit significantly effect consumer purchase intention in Company C. Originality/value: This study represents purchase intention in the consumer-to-consumer e-commerce by investigating three case study using technology acceptance model as a guiding theory.

  17. Factors Influencing Environmental Management Practices Among Hotels in Malaysia

    OpenAIRE

    Zaiton Samdin; Kasimu Abdu Bakori; Hamimah Hassan

    2012-01-01

    This paper attempts to investigate the factors that influence hotel managers- attitudes towards sustainable tourism practices (STP) in Kuala Lumpur and the state of Selangor in Malaysia. The study distributes 104 questionnaires to hotels ranging from one star to five-star categories including budget hotels. Out of this figure, 60 copies of the questionnaires were returned and analyzed. The finding revealed that of all the seven factors investigated, only the variables measuring incentives and...

  18. Influence of obesity-related risk factors in the aetiology of glioma

    DEFF Research Database (Denmark)

    Disney-Hogg, Linden; Sud, Amit; Law, Philip J

    2018-01-01

    BACKGROUND: Obesity and related factors have been implicated as possible aetiological factors for the development of glioma in epidemiological observation studies. We used genetic markers in a Mendelian randomisation framework to examine whether obesity-related traits influence glioma risk. This ...

  19. Factors influencing perceived sustainability of Dutch community health programs

    NARCIS (Netherlands)

    Vermeer, A. J. M.; van Assema, P.; Hesdahl, B.; Harting, J.; de Vries, N. K.

    2015-01-01

    We assessed the perceived sustainability of community health programs organized by local intersectoral coalitions, as well as the factors that collaborating partners think might influence sustainability. Semi-structured interviews were conducted among 31 collaborating partners of 5 community health

  20. Factors influencing offspring traits in the oviparous multi-clutched ...

    Indian Academy of Sciences (India)

    Unknown

    Calotes versicolor, a multi-clutched oviparous lizard. (Shanbhag and Prasad ... composes correlation between two variables in to: (i) the direct effect of the first ... color breeding time is the prime factor that influences the clutch mass and egg ...