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Sample records for factors influencing perch

  1. Reappraising factors affecting mourning dove perch coos

    USGS Publications Warehouse

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

    1978-01-01

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

  2. Influence of perched groundwater on base flow

    USGS Publications Warehouse

    Niswonger, R.G.; Fogg, G.E.

    2008-01-01

    Analysis with a three-dimensional variably saturated groundwater flow model provides a basic understanding of the interplay between streams and perched groundwater. A simplified, layered model of heterogeneity was used to explore these relationships. Base flow contribution from perched groundwater was evaluated with regard to varying hydrogeologic conditions, including the size and location of the fine-sediment unit and the hydraulic conductivity of the fine-sediment unit and surrounding coarser sediment. Simulated base flow was sustained by perched groundwater with a maximum monthly discharge in excess of 15 L/s (0.6 feet3/s) over the length of the 2000-m stream reach. Generally, the rate of perched-groundwater discharge to the stream was proportional to the hydraulic conductivity of sediment surrounding the stream, whereas the duration of discharge was proportional to the hydraulic conductivity of the fine-sediment unit. Other aspects of the perched aquifer affected base flow, such as the depth of stream penetration and the size of the fine-sediment unit. Greater stream penetration decreased the maximum base flow contribution but increased the duration of contribution. Perched groundwater provided water for riparian vegetation at the demand rate but reduced the duration of perched-groundwater discharge nearly 75%. Copyright 2008 by the American Geophysical Union.

  3. The interactions of abiotic and biotic factors influencing perch Perca fluviatilis and roach Rutilus rutilus populations in small acidified boreal lakes.

    PubMed

    Linløkken, A N; Hesthagen, T

    2011-08-01

    Four small, acidified boreal lakes, all sustaining populations of perch Perca fluviatilis, roach Rutilus rutilus and pike Esox lucius, were studied in four successive years. Three lakes were moderately acidified (mean pH of 5·61-5·83), while the fourth was more acidic (mean pH of 5·16) and had a sparse population of R. rutilus. Perca fluviatilis density was higher in this lake (1004 ha(-1)) than in the other three (355-717 ha(-1)), where R. rutilus dominated in terms of numbers (981-2185 ha(-1)). Large, potentially predatory, P. fluviatilis were most abundant in the lake with clearest water, and these seemed to have a negative effect on P. fluviatilis density. Perca fluviatilis mean mass was negatively correlated with R. rutilus biomass and was highest in the most acidic lake with the sparse R. rutilus and the highest P. fluviatilis density. Perca fluviatilis mass correlated positively with pH in two lakes (with the highest fish biomass), suggesting that low pH affected P. fluviatilis mass negatively. Perca fluviatilis growth correlated positively with summer (July to August) air temperature in the lake with sparse R. rutilus, thus differing from P. fluviatilis and R. rutilus growth in the other three lakes. The mean age of P. fluviatilis was generally lower than that of R. rutilus and was lowest in the two lakes with the highest fish biomass, indicating that adult mortality was affected by density-induced factors.

  4. Perched water tables on hillsides in western Oregon: I. Some factors affecting their development and longevity.

    USGS Publications Warehouse

    Hammermeister, D.P.; Kling, G.F.; Vomocil, J.A.

    1982-01-01

    Perched water tables on hillsides located on the western border of the Willamette Valley in Oregon in some cases have the potential to transport pollutants from either domestic or agricultural sources downslope to streams, ponds, or reservoirs, resulting in the deterioration of the quality of these waters. Some factors responsible for the development and longevity of these potentially problem-causing perched water tables on three hillsides were examined. -from Authors

  5. Influence of environmental enrichment on injurious pecking and perching behaviour in young turkeys.

    PubMed

    Martrenchar, A; Huonnig, D; Cotte, J P

    2001-05-01

    1. In order to reduce injurious pecking, the influence of environmental enrichment on pecking and perching behaviour was studied in young male and female turkeys. 2. Two different types of enrichment and a control treatment (TO) were tested: T1, metal objects and straw; T2, similar to T1 + wood perches. Birds were housed in 36 m2 pens at a light intensity of 5 lux with 4 replicates per treatment in a 2x3 factorial design. 3. Pecking at objects and perching behaviour were observed weekly. Behaviour was video recorded at weeks 5 and 10. Birds were examined daily for the occurrence of injuries. At the end of the rearing period, an ACTH challenge was performed and H/L ratio was measured. 4. Objects were regularly pecked at. Perching was more common in females, peaked at week 5 (10% to 13% of birds perched) and declined to 0% by week 10. Aggressive pecking was more frequently observed in males in T0 than in T1 or T2 at week 10. Wing (in males and females), tail and head (in males) injuries were more common in T0 than in T1 or T2. T1 and T2 were similar Response to ACTH challenge and H/L ratio were not consistently influenced by treatments. 5. It is concluded that metal objects and straw reduced injurious pecking in young female and male turkeys by redirecting, pecking activity.

  6. Ultraviolet Radiation Influences Perch Selection by a Neotropical Poison-Dart Frog

    PubMed Central

    Kats, Lee B.; Bucciarelli, Gary M.; Schlais, David E.; Blaustein, Andrew R.; Han, Barbara A.

    2012-01-01

    Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy. PMID:23251505

  7. Ultraviolet radiation influences perch selection by a neotropical poison-dart frog.

    PubMed

    Kats, Lee B; Bucciarelli, Gary M; Schlais, David E; Blaustein, Andrew R; Han, Barbara A

    2012-01-01

    Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy. PMID:23251505

  8. Ultraviolet radiation influences perch selection by a neotropical poison-dart frog.

    PubMed

    Kats, Lee B; Bucciarelli, Gary M; Schlais, David E; Blaustein, Andrew R; Han, Barbara A

    2012-01-01

    Ambient ultraviolet-B radiation can harm amphibian eggs, larvae and adults. However, some amphibians avoid UV-B radiation when given the opportunity. The strawberry poison dart frog, Oophaga pumilio, is diurnal and males vocalize throughout the day in light gaps under forest canopies that expose them to solar radiation. Previous studies have demonstrated that males calling from high perches are more successful at mating than those at lower perches. We investigated whether frogs at higher perches receive more ultraviolet-B than those calling from lower perches. We also investigated whether frogs on perches receiving relatively low ultraviolet-B levels maintained their positions for longer compared to individuals calling from perches receiving higher levels of ultraviolet-B. Finally, since it has been hypothesized that some animals utilize levels of UV-A as a visual cue to avoid UV-B damage, we artificially elevated ultraviolet-A levels to examine whether males exposed to artificially elevated ultraviolet-A abandoned their perches sooner compared to males exposed to visible light. We found that frogs called from perches receiving low ultraviolet-B regardless of perch height, and that frogs maintain their positions longer on perches receiving low ultraviolet-B compared to perches receiving even slightly higher ultraviolet-B levels. Exposing the frogs to artificially elevated levels of ultraviolet-A radiation caused males to move off of their perches faster than when they were exposed to a control light source. These experiments suggest that ultraviolet radiation plays an important role in frog behavior related to perch selection, even in rainforests where much of the solar radiation is shielded by the forest canopy.

  9. The influence of providing perches and string on activity levels, fearfulness and leg health in commercial broiler chickens.

    PubMed

    Bailie, C L; O'Connell, N E

    2015-04-01

    string, and therefore that these stimuli have the potential to improve welfare. In addition, provision of string as a pecking device appeared to positively influence walking ability. However, this effect was numerically small, was only shown in certain weeks and was not reflected in the other leg health measure (latency to lie). The results also showed an apparent negative effect of string and perches on the activity levels of birds (recorded away from the immediate vicinity of these enrichments) towards the end of the production cycle. These results emphasise the need for further research into optimum design and layout of enrichment stimuli for modern broilers in windowed houses to ensure that their provision leads to clear welfare benefits. PMID:25440236

  10. The influence of providing perches and string on activity levels, fearfulness and leg health in commercial broiler chickens.

    PubMed

    Bailie, C L; O'Connell, N E

    2015-04-01

    string, and therefore that these stimuli have the potential to improve welfare. In addition, provision of string as a pecking device appeared to positively influence walking ability. However, this effect was numerically small, was only shown in certain weeks and was not reflected in the other leg health measure (latency to lie). The results also showed an apparent negative effect of string and perches on the activity levels of birds (recorded away from the immediate vicinity of these enrichments) towards the end of the production cycle. These results emphasise the need for further research into optimum design and layout of enrichment stimuli for modern broilers in windowed houses to ensure that their provision leads to clear welfare benefits.

  11. The influence of sex and environmental temperature on the acute stress response of juvenile yellow perch Perca flavescens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow perch are an ecologically and economically important fish in North America. At its peak, the Great Lakes yellow perch fishery constituted the largest inland capture fishery in North America. Even though wild populations have declined, consumer demand for yellow perch remains high, which has...

  12. Influence of domestication process on immune response to repeated emersion stressors in Eurasian perch (Perca fluviatilis, L.).

    PubMed

    Douxfils, J; Lambert, S; Mathieu, C; Milla, S; Mandiki, S N M; Henrotte, E; Wang, N; Dieu, M; Raes, M; Rougeot, C; Kestemont, P

    2014-03-25

    Domestication might be a possible way to reduce the physiological response to long-term stressors and deleterious effects on immunity. The present study aimed to evaluate the chronic immune response induced by repeated emersions and the possible impact of domestication by comparing farmed Eurasian perch with short (F1) and long (F4) captive-life history. In the first experiment, fish were exposed to a single emersion and physiological stress response was measured in the short term to characterize fish sensitivity to the tested stressor. Serum cortisol and glucose elevated within 6h post-stress and splenosomatic index (SSI) decreased within 48h, indicating that the species was affected by emersion stressor. In the second experiment, F1 and F4 generations were submitted to repeated water emersions (3 times/week during 44days). On day 9, 18 and 44, samplings were performed 48h post-stressor to highlight any sustained disruption of immune system. Serum cortisol, glucose, SSI and lysozyme activity were evaluated and serum proteome was analyzed using 2D-DIGE. Any of the tested variables were affected by repeated emersions and proteomic analysis only revealed that alpha-2 macroglobulins (a2Ms) were up-regulated in the serum of stressed individuals. Domestication also resulted in the up-regulation of five a2M isoforms and down-regulation of complement C3 and Ig light chain proteins, independently of any stressor exposure. In conclusion, the results suggested that repeated emersions are not severe stressors for Eurasian perch, probably explaining why domestication had no influence on fish responses. Changes associated with domestication are highly complex and certainly need further investigations.

  13. Numerical modeling of perched water under Yucca Mountain, Nevada

    USGS Publications Warehouse

    Hinds, J.J.; Ge, S.; Fridrich, C.J.

    1999-01-01

    The presence of perched water near the potential high-level nuclear waste repository area at Yucca Mountain, Nevada, has important implications for waste isolation. Perched water occurs because of sharp contrasts in rock properties, in particular between the strongly fractured repository host rock (the Topopah Spring welded tuff) and the immediately underlying vitrophyric (glassy) subunit, in which fractures are sealed by clays that were formed by alteration of the volcanic glass. The vitrophyre acts as a vertical barrier to unsaturated flow throughout much of the potential repository area. Geochemical analyses (Yang et al. 1996) indicate that perched water is relatively young, perhaps younger than 10,000 years. Given the low permeability of the rock matrix, fractures and perhaps fault zones must play a crucial role in unsaturated flow. The geologic setting of the major perched water bodies under Yucca Mountain suggests that faults commonly form barriers to lateral flow at the level of the repository horizon, but may also form important pathways for vertical infiltration from the repository horizon down to the water table. Using the numerical code UNSAT2, two factors believed to influence the perched water system at Yucca Mountain, climate and fault-zone permeability, are explored. The two-dimensional model predicts that the volume of water held within the perched water system may greatly increase under wetter climatic conditions, and that perched water bodies may drain to the water table along fault zones. Modeling results also show fault flow to be significantly attenuated in the Paintbrush Tuff non-welded hydrogeologic unit.

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

    PubMed

    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

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

    PubMed

    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.

  16. Recruitment synchrony of yellow perch (Perca flavescens, Percidae) in the Great Lakes region, 1966–2008

    USGS Publications Warehouse

    Honsey, Andrew E.; Bunnell, David; Troy, Cary D.; Fielder, David G.; Thomas, Michael V.; Knight, Carey T.; Chong, Stephen; Hook, Tomas O.

    2016-01-01

    Population-level reproductive success (recruitment) of many fish populations is characterized by high inter-annual variation and related to annual variation in key environmental factors (e.g., climate). When such environmental factors are annually correlated across broad spatial scales, spatially separated populations may display recruitment synchrony (i.e., the Moran effect). We investigated inter-annual (1966–2008) variation in yellow perch (Perca flavescens, Percidae) recruitment using 16 datasets describing populations located in four of the five Laurentian Great Lakes (Erie, Huron, Michigan, and Ontario) and Lake St. Clair. We indexed relative year class strength using catch-curve residuals for each year-class across 2–4 years and compared relative year-class strength among sampling locations. Results indicate that perch recruitment is positively synchronized across the region. In addition, the spatial scale of this synchrony appears to be broader than previous estimates for both yellow perch and freshwater fish in general. To investigate potential factors influencing relative year-class strength, we related year-class strength to regional indices of annual climatic conditions (spring-summer air temperature, winter air temperature, and spring precipitation) using data from 14 weather stations across the Great Lakes region. We found that mean spring-summer temperature is significantly positively related to recruitment success among Great Lakes yellow perch populations.

  17. Escape tactics and effects of perch height and habituation on flight initiation distance in two Jamaican anoles (Squamata: polychrotidae).

    PubMed

    Cooper, William E

    2010-12-01

    Escape by Anolis lizards is influenced by microhabitats and fight initiation distance increases with predation risk. Differences in microhabitat use among ecomorphs affect escape behavior, but only two studies have reported ecomorphological differences in flight initiation distance among Greater Antillean species. I studied effects of predation risk and microhabitats on escape behavior by conducting field experiments using two species of anoles, Anolis lineatopus and A. grahami, on the campus of the University of the West Indies at Mona, Jamaica. Because ecomorphological variation of anoles has evolved independently within each island of the Greater Antilles, but relationships between ecomorphs and escape behaviors are poorly known, I characterized microhabitat use and escape tactics, and determined relationships between flight initiation distance and two risk factors, habituation to human presence and perch height, in Anolis lineatopus, a trunk-ground anole and A. grahami, a trunk-crown anole. Sample sizes for A. lineatopus and A. grahami were 214 and 93, for microhabitat use and escape destinations, 74 and 34 for human presence and 125 and 34 for perch height. The two species occurred in similar microhabitats and exhibited similar escape tactics, but exhibited key differences expected for their ecomorphs. Both species were sighted frequently on the ground and on trees, but A. lineatopus were more frequently on ground and were perched lower than A. grahami. Both species escaped from ground to trees and when on trees hid on far sides and escaped without changing climbing direction with equal frequency. The frequency of fleeing upward was greater for A. grahami than A. lineatopus. Both species exhibited habituation by having shorter flight initiation distances in areas with more frequent exposure to people. In both species flight initiation distance increased as perch height decreased because, lizards had to climb farther to be out of reach when perched lower. The

  18. Perch width preferences of laying hens.

    PubMed

    Struelens, E; Tuyttens, F A M; Ampe, B; Odberg, F; Sonck, B; Duchateau, L

    2009-07-01

    1. In order to investigate the effect of perch width on perching behaviour of laying hens, two experiments in which hens could choose between 7 different perch widths (1.5, 3.0, 4.5, 6.0, 7.5, 9.0 and 10.5 cm) were conducted. In one experiment (EXP-2P) test cages contained two long perches gradually broadening and narrowing stepwise, in the other experiment (EXP-7P) 7 separate short perches differing in width were placed in the test cages. In each experiment 12 groups of 4 hens were filmed during day and night. The behaviour and location of the hens were recorded and whether the nest box affected hen distribution over the perches was investigated. 2. During daytime, in EXP-2P, there was an increase in perch use with increasing perch width. Hens spent less time on perches of 1.5 cm wide compared to perches of 9.0 and 10.5 cm wide. In EXP-7P, the 1.5-cm wide perch was also used the least (but only the difference with 4.5-cm wide perches was statistically significant) but perch use did not increase linearly with perch width. During the night, there were no significant perch width preferences in either experiment. 3. The percentage of active behaviours (preening, walking, drinking, pecking at hen) versus passive behaviours (standing, sitting, sleeping) did not differ significantly according to perch width. 4. In EXP-7P, there was a trend for perch use to decrease with greater distances to the nest box in the morning. 5. A perch width of 1.5 cm is not recommended for laying hens. For wider perch widths, results were equivocal: they tend to support rather than challenge the widespread use of 4.5-cm wide perches in commercial units.

  19. Host-parasite relationships as determinants of heavy metal concentrations in perch (Perca fluviatilis) and its intestinal parasite infection.

    PubMed

    Brázová, Tímea; Hanzelová, Vladimíra; Miklisová, Dana; Šalamún, Peter; Vidal-Martínez, Víctor M

    2015-12-01

    The concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn and their bioconcentration factors (BCFs) were determined in two intestinal parasites, an acanthocephalan, Acanthocephalus lucii, a tapeworm, Proteocephalus percae, present in the same host, the European perch (Perca fluviatilis, L.), in the heavily polluted Ružín reservoir in eastern Slovakia. The bioaccumulation of heavy metals in the fish organs and parasites was studied for acanthocephalan and tapeworm monoinfections or mixed infections by the two parasites and for the size of their parasitic infrapopulations. Bioconcentration factors (c[parasite]/c[muscle tissue]) showed that the concentrations of As, Ni, Pb and Zn were higher in mixed infections than in monoinfections. Negative correlations between heavy metal concentrations in perch organs and the parasites were found. For example, higher concentrations of Ni and Zn in both parasite species corresponded with lower metal concentrations in perch and hard roe. Likewise, significant negative relationships between metal concentrations in fish organs and number of parasites were noticed with lower levels of Pb in fish harbouring higher numbers of tapeworms. Similarly, in both parasite species the concentrations of some essential elements (Cr, Mn) were lower at high infection intensities compared to low intensities. Our study revealed that the differential concentration of heavy metals in perch organs was affected by the type of infection (mono- or mixed-infection), and needs to be considered in field ecotoxicological and parasitological studies as a potentially important factor influencing the pollutant concentrations in fish.

  20. Host-parasite relationships as determinants of heavy metal concentrations in perch (Perca fluviatilis) and its intestinal parasite infection.

    PubMed

    Brázová, Tímea; Hanzelová, Vladimíra; Miklisová, Dana; Šalamún, Peter; Vidal-Martínez, Víctor M

    2015-12-01

    The concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn and their bioconcentration factors (BCFs) were determined in two intestinal parasites, an acanthocephalan, Acanthocephalus lucii, a tapeworm, Proteocephalus percae, present in the same host, the European perch (Perca fluviatilis, L.), in the heavily polluted Ružín reservoir in eastern Slovakia. The bioaccumulation of heavy metals in the fish organs and parasites was studied for acanthocephalan and tapeworm monoinfections or mixed infections by the two parasites and for the size of their parasitic infrapopulations. Bioconcentration factors (c[parasite]/c[muscle tissue]) showed that the concentrations of As, Ni, Pb and Zn were higher in mixed infections than in monoinfections. Negative correlations between heavy metal concentrations in perch organs and the parasites were found. For example, higher concentrations of Ni and Zn in both parasite species corresponded with lower metal concentrations in perch and hard roe. Likewise, significant negative relationships between metal concentrations in fish organs and number of parasites were noticed with lower levels of Pb in fish harbouring higher numbers of tapeworms. Similarly, in both parasite species the concentrations of some essential elements (Cr, Mn) were lower at high infection intensities compared to low intensities. Our study revealed that the differential concentration of heavy metals in perch organs was affected by the type of infection (mono- or mixed-infection), and needs to be considered in field ecotoxicological and parasitological studies as a potentially important factor influencing the pollutant concentrations in fish. PMID:26432028

  1. Efficacy of exogenous hormone (GnRHa) for induced breeding of climbing perch Anabas testudineus (Bloch, 1792) and influence of operational sex ratio on spawning success.

    PubMed

    Mandal, Babita; Kumar, Rajesh; Jayasankar, P

    2016-08-01

    The climbing perch, Anabas testudineus, is an air-breathing fish having great consumer preference as a food fish and is considered a prime candidate species for aquaculture. Spawning success is an important issue while using hormones for captive induced breeding. In the first experiment, a trial was conducted to assess the efficacy of a synthetic Gonadotropin Releasing Hormone analog (sGnRHa) on the spawning success of climbing perch. Female fish were administered six different doses each with a single intramuscular injection of sGnRHa hormone at 0.002 (TOD1), 0.005 (TOD2), 0.01 (TOD3), 0.015 (TOD4), 0.02 (TOD5), 0.03 (TOD6) μg/g body weight. Similarly, males were administered half of the hormone dose of females in all the respective treatment groups. The greatest (P<0.05) relative fecundity (715.13±15.0 eggs/g female body weight) and fertilization percentage rates (93.1±8.0%) occurred when female fish were treated at the 0.015μg/g body weight dose. There was a reduction in relative fecundity and hatching rate in female fish injected with the largest dose (1.5μL/g body weight) of sGnRHa. A second experiment was conducted to assess the effect of a different male-female ratio on optimum spawning success in climbing perch. For this study a different female to male ratio (1:1, 1:2, 1:3 and 1:4) and male to female ratio (1:1, 1:2 and 1:3) were used. There were a greater (P<0.05) relative fecundity (886.62±17.9 eggs/g female body weight), fertilization (98±6.7%) and hatching (99±5.4%) rates with the female to male ratio of 1:2. This indicated that the hormone dose of 0.015μg/g body weight and a female-male ratio of 1:2 are optimal for enhanced spawning success in the climbing perch. PMID:27346586

  2. Efficacy of exogenous hormone (GnRHa) for induced breeding of climbing perch Anabas testudineus (Bloch, 1792) and influence of operational sex ratio on spawning success.

    PubMed

    Mandal, Babita; Kumar, Rajesh; Jayasankar, P

    2016-08-01

    The climbing perch, Anabas testudineus, is an air-breathing fish having great consumer preference as a food fish and is considered a prime candidate species for aquaculture. Spawning success is an important issue while using hormones for captive induced breeding. In the first experiment, a trial was conducted to assess the efficacy of a synthetic Gonadotropin Releasing Hormone analog (sGnRHa) on the spawning success of climbing perch. Female fish were administered six different doses each with a single intramuscular injection of sGnRHa hormone at 0.002 (TOD1), 0.005 (TOD2), 0.01 (TOD3), 0.015 (TOD4), 0.02 (TOD5), 0.03 (TOD6) μg/g body weight. Similarly, males were administered half of the hormone dose of females in all the respective treatment groups. The greatest (P<0.05) relative fecundity (715.13±15.0 eggs/g female body weight) and fertilization percentage rates (93.1±8.0%) occurred when female fish were treated at the 0.015μg/g body weight dose. There was a reduction in relative fecundity and hatching rate in female fish injected with the largest dose (1.5μL/g body weight) of sGnRHa. A second experiment was conducted to assess the effect of a different male-female ratio on optimum spawning success in climbing perch. For this study a different female to male ratio (1:1, 1:2, 1:3 and 1:4) and male to female ratio (1:1, 1:2 and 1:3) were used. There were a greater (P<0.05) relative fecundity (886.62±17.9 eggs/g female body weight), fertilization (98±6.7%) and hatching (99±5.4%) rates with the female to male ratio of 1:2. This indicated that the hormone dose of 0.015μg/g body weight and a female-male ratio of 1:2 are optimal for enhanced spawning success in the climbing perch.

  3. Phonological Awareness: Factors of Influence

    ERIC Educational Resources Information Center

    Frohlich, Linda Paulina; Petermann, Franz; Metz, Dorothee

    2013-01-01

    Early child development is influenced by various genetic and environmental factors. This study aims to identify factors that affect the phonological awareness of preschool and first grade children. Based on a sample of 330 German-speaking children (mean age = 6.2 years) the following domains were evaluated: Parent factors, birth and pregnancy,…

  4. Perch compliance and experience affect destination choice of brown tree snakes (Boiga irregularis).

    PubMed

    Mauro, A Alexander; Jayne, C Bruce

    2016-04-01

    Arboreal animals often encounter branches with variable diameters that are highly correlated with stiffness, but how surface compliance affects the perch choice of animals is poorly understood. We used artificial branches to test the effects of different diameters and compliance on the choice between two destinations for twenty brown tree snakes as they bridged gaps. When both destinations were rigid, the diameters of the surfaces did not affect perch choice. However, with increased experience snakes developed a preference for a rigid, large-diameter perch compared to a compliant, small-diameter perch that collapsed under loads that were a small fraction of the weight of the snake. In hundreds of trials, with only one exception, the snakes proceeded to crawl entirely onto all rigid perches after first touching them, whereas the snakes commonly withdrew from the compliant perch even after touching it so lightly that it did not collapse. Hence, both tactile and visual cues appear to influence how these animals select a destination while crossing a gap. The preference for the rigid, large-diameter perch compared to the compliant, small-diameter perch developed mainly from short-term learning during three successive trials per testing session per individual. Furthermore, a preference for large diameters did not persist in the final treatment which used a rigid, large-diameter perch and a rigid, small-diameter perch. Hence, brown tree snakes appeared to be able to form short-term associations between the perch appearance and stiffness, the latter of which may have been determined via tactile sensory input.

  5. Perch compliance and experience affect destination choice of brown tree snakes (Boiga irregularis).

    PubMed

    Mauro, A Alexander; Jayne, C Bruce

    2016-04-01

    Arboreal animals often encounter branches with variable diameters that are highly correlated with stiffness, but how surface compliance affects the perch choice of animals is poorly understood. We used artificial branches to test the effects of different diameters and compliance on the choice between two destinations for twenty brown tree snakes as they bridged gaps. When both destinations were rigid, the diameters of the surfaces did not affect perch choice. However, with increased experience snakes developed a preference for a rigid, large-diameter perch compared to a compliant, small-diameter perch that collapsed under loads that were a small fraction of the weight of the snake. In hundreds of trials, with only one exception, the snakes proceeded to crawl entirely onto all rigid perches after first touching them, whereas the snakes commonly withdrew from the compliant perch even after touching it so lightly that it did not collapse. Hence, both tactile and visual cues appear to influence how these animals select a destination while crossing a gap. The preference for the rigid, large-diameter perch compared to the compliant, small-diameter perch developed mainly from short-term learning during three successive trials per testing session per individual. Furthermore, a preference for large diameters did not persist in the final treatment which used a rigid, large-diameter perch and a rigid, small-diameter perch. Hence, brown tree snakes appeared to be able to form short-term associations between the perch appearance and stiffness, the latter of which may have been determined via tactile sensory input. PMID:26723759

  6. Factors That Influence Teacher Attrition.

    ERIC Educational Resources Information Center

    Gonzalez, Patricia

    1995-01-01

    External, employment, and personal factors which influence teacher decisions to stay, leave, or transfer from teaching assignments are discussed, with emphasis on special education teachers. Factors attributed to teacher attrition in urban and rural environments also are briefly reviewed, along with attrition of related services professionals.…

  7. Food of white perch, rock bass and yellow perch in eastern Lake Ontario

    USGS Publications Warehouse

    Elrod, Joseph H.; Busch, Wolf-Dieter N.; Griswold, Bernard L.; Schneider, Clifford P.; Wolfert, David R.

    1981-01-01

    The contents of stomachs from 1,485 white perch, 218 rock bass and 1,399 yellow perch collected in eastern Lake Ontario from May to October in 1972 and in May 1973 were examined. All three species fed primarily on amphipods, but they also ate chironomids and trichopterans regularly. Rock bass ate more trichopterans than chironomids, whereas white perch and yellow perch ate more chironomids. Snails and crayfish were significant items in the diet of rock bass, but occurred infrequently in stomachs of white perch and yellow perch. White perch and yellow perch frequently ate fish eggs during early summer, but rock bass seldom ate fish eggs. Fish were important in the diets of white perch longer than 300 millimeters and rock bass and yellow perch longer than 200 millimeters. Similarities in the diets of fish 1 year old or older suggest that the potential for competition between white perch and yellow perch is greater than that between rock bass and either white perch or yellow perch.

  8. Growth and potential yield of perch (Perca spp.) in selected areas of Lake Baikal and the Laurentian Great Lakes

    USGS Publications Warehouse

    O'Gorman, Robert; Bronte, Charles R.; Hatcher, Charles O.; Pronin, Nikolai M.; Sokolnikov, Yury

    1998-01-01

    We compared growth, mortality, and potential yield of Eurasian perch (Perca fluviatilis) from Chivirkui Bay in Lake Baikal with that of yellow perch (P. flavescens) from three areas of the Laurentian Great Lakes --Chequamegon Bay in Lake Superior, northeastern Lake Ontario, and southwestern Lake Erie. Graded mesh gill nets were fished in August to sample perch in lakes Baikal (1993), Ontario (1985-93), and Erie (1994). Bottom trawls were fished in July-August to sample perch in Lake Superior (1973-93). Adult yellow perch from the Laurentian Great Lakes were heavier at most lengths than adult Eurasian perch from Lake Baikal. The increase in body weight per unit increase in length was greatest in Lake Erie. Total annual mortality of perch was low in Lake Baikal (0.31), intermediate in lakes Superior (0.41) and Ontario (0.54), and high in Lake Erie (0.66). Annual fishing mortality (u) for perch in Lake Baikal was 60%-70% lower than that for perch in the Great Lakes. At ages 1-3, perch in Lake Erie were longer than those in lakes Baikal, Superior, and Ontario but at ages 4-9 perch in Lake Baikal were longer than those in the other lakes. Although Eurasian perch in Lake Baikal were longer at age 4 and older, growth in length, as measured by the Brody growth coefficient, K, was lower there than in the other lakes and was similar to that in Lake Superior; yellow perch in Lake Erie grew the fastest. Yield-per-recruit was lowest in Lake Erie and highest in Lake Superior. Potential yield was influenced by growth rates and fishing mortality.

  9. Factors Influencing College Science Success

    ERIC Educational Resources Information Center

    Tai, Robert H.; Sadler, Philip M.; Mintzes, Joel J.

    2006-01-01

    In this paper, the authors report some of the salient findings of a large-scale, four-year national study, conducted at the Harvard-Smithsonian Center for Astrophysics, entitled "Factors Influencing College Science Success" (FICSS), which surveyed college students who enrolled in first-year biology, chemistry, and physics courses throughout the…

  10. Soft Factors Influence College Enrollment

    ERIC Educational Resources Information Center

    Fogg, Neeta P.; Harrington, Paul E.

    2010-01-01

    Evidence about the role that "soft factors" like student engagement and school environment play in influencing whether high school students go on to enroll in college is hard to come by. Over the past two years, the Center for Labor Market Studies (CLMS) of Northeastern University, with support from the Nellie Mae Education Foundation and the…

  11. Thermal acclimation in the perch (Perca fluviatilis L.) immunity.

    PubMed

    Marnila, Pertti; Lilius, Esa-Matti

    2015-12-01

    Fish immune systems must be able to cope with pathogens over a wide temperature range. Earlier research suggest that fish are more dependent on innate immune responses based on pattern recognition than acquired functions with specific recognition. If this applies to phagocytes, then opsonins (serum factors that augment phagocytosis e.g. immunoglobulins and complement proteins) attached on zymosan (Z) particles should be recognized better at higher temperatures than Z only. Z is recognized by glucan receptor representing pattern recognition. In this study perch were acclimated to 5 °C or 16 °C for 3-5 weeks. The recognition and activation of respiratory burst reaction of peripheral blood phagocytes was examined at seven different measurement temperatures (5, 10, 16, 20, 24 27, and 30 °C) when the cells were stimulated with Z and serum opsonized zymosan (OZ). Respiratory burst was measured as luminol chemiluminescence (CL) from diluted whole blood. OZ-induced CL per volume of blood was on average approximately 4.6 times higher in 16 °C acclimated fish than 5 °C acclimated perch (P<0.0001). Z-induced CL was approximately 3 times higher at lower temperatures in 16 °C acclimated perch than 5 °C acclimated fish and 6-9 times higher at 27 °C and 30 °C (P<0.001), respectively. CL reaction kinetics were faster in perch acclimated to 5 °C than 16 °C -acclimated fish, especially at low temperatures (P<0.001). Thermal acclimation caused a 3-4 °C shift in temperature response curves of CL towards the acclimation temperature (P<0.0001 and P<0.053 in Z and OZ-induced CL, respectively). Serum opsonins activated perch phagocytes substantially better at higher temperatures in both acclimation groups, which is consistent with an earlier study in rainbow trout (O. mykiss). However, opsonin recognition was significantly better in 16 °C acclimated perch than 5 °C acclimated fish, which was seen as higher CLs for OZ compared to Z, especially at higher temperatures. This is

  12. A modeling study of perched water phenomena in the vadose zone

    SciTech Connect

    Wu, Y.-S.; Ritchey, A. C.; Bodvarsson, G. S.

    1997-12-16

    vicinity of investigating the perched water zones indicates that: (1) no large-scale connected fractures intersect the underlying low-permeability units, and (2) both vertical and horizontal permeabilities within the perched water zone must be small when compared with measurements outside these zones. This modeling study indicates that the key factors necessary to create a perched-water zone using a numerical model are: (1) a water perching geologic structure with low permeability zones or a capillary barrier underlain and surrounding, (2) weak capillary forces under high saturation condition within and near perched-water zones, and (3) sufficient water infiltration rates.

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

    SciTech Connect

    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.

  14. Waterscape genetics of the yellow perch (Perca flavescens): patterns across large connected ecosystems and isolated relict populations.

    PubMed

    Sepulveda-Villet, Osvaldo J; Stepien, Carol A

    2012-12-01

    Comparisons of a species' genetic diversity and divergence patterns across large connected populations vs. isolated relict areas provide important data for understanding potential response to global warming, habitat alterations and other perturbations. Aquatic taxa offer ideal case studies for interpreting these patterns, because their dispersal and gene flow often are constrained through narrow connectivity channels that have changed over geological time and/or from contemporary anthropogenic perturbations. Our research objective is to better understand the interplay between historic influences and modern-day factors (fishery exploitation, stocking supplementation and habitat loss) in shaping population genetic patterns of the yellow perch Perca flavescens (Percidae: Teleostei) across its native North American range. We employ a modified landscape genetics approach, analysing sequences from the entire mitochondrial DNA control region and 15 nuclear DNA microsatellite loci of 664 spawning adults from 24 populations. Results support that perch from primary glacial refugium areas (Missourian, Mississippian and Atlantic) founded contemporary northern populations. Genetic diversity today is highest in southern (never glaciated) populations and also is appreciable in northern areas that were founded from multiple refugia. Divergence is greater among isolated populations, both north and south; the southern Gulf Coast relict populations are the most divergent, reflecting their long history of isolation. Understanding the influence of past and current waterway connections on the genetic structure of yellow perch populations may help us to assess the roles of ongoing climate change and habitat disruptions towards conserving aquatic biodiversity.

  15. Factors influencing pacing in triathlon

    PubMed Central

    Wu, Sam SX; Peiffer, Jeremiah J; Brisswalter, Jeanick; Nosaka, Kazunori; Abbiss, Chris R

    2014-01-01

    Triathlon is a multisport event consisting of sequential swim, cycle, and run disciplines performed over a variety of distances. This complex and unique sport requires athletes to appropriately distribute their speed or energy expenditure (ie, pacing) within each discipline as well as over the entire event. As with most physical activity, the regulation of pacing in triathlon may be influenced by a multitude of intrinsic and extrinsic factors. The majority of current research focuses mainly on the Olympic distance, whilst much less literature is available on other triathlon distances such as the sprint, half-Ironman, and Ironman distances. Furthermore, little is understood regarding the specific physiological, environmental, and interdisciplinary effects on pacing. Therefore, this article discusses the pacing strategies observed in triathlon across different distances, and elucidates the possible factors influencing pacing within the three specific disciplines of a triathlon. PMID:25258562

  16. Factors influencing pacing in triathlon.

    PubMed

    Wu, Sam Sx; Peiffer, Jeremiah J; Brisswalter, Jeanick; Nosaka, Kazunori; Abbiss, Chris R

    2014-01-01

    Triathlon is a multisport event consisting of sequential swim, cycle, and run disciplines performed over a variety of distances. This complex and unique sport requires athletes to appropriately distribute their speed or energy expenditure (ie, pacing) within each discipline as well as over the entire event. As with most physical activity, the regulation of pacing in triathlon may be influenced by a multitude of intrinsic and extrinsic factors. The majority of current research focuses mainly on the Olympic distance, whilst much less literature is available on other triathlon distances such as the sprint, half-Ironman, and Ironman distances. Furthermore, little is understood regarding the specific physiological, environmental, and interdisciplinary effects on pacing. Therefore, this article discusses the pacing strategies observed in triathlon across different distances, and elucidates the possible factors influencing pacing within the three specific disciplines of a triathlon.

  17. Relationship between mercury accumulation in young-of-the-year yellow perch and water-level fluctuations

    USGS Publications Warehouse

    Sorensen, J.A.; Kallemeyn, L.W.; Sydor, M.

    2005-01-01

    A three-year (2001 -2003) monitoring effort of 14 northeastern Minnesota lakes was conducted to document relationships between water-level fluctuations and mercury bioaccumulation in young-of-the-year (YOY) yellow perch (Perca flavescens) collected in the fall of each year at fixed locations. Six of those lakes are located within or adjacent to Voyageurs National Park and are influenced by dams on the outlets of Rainy and Namakan lakes. One site on Sand Point Lake coincides with a location that has nine years of previous monitoring suitable for addressing the same issue over a longer time frame. Mean mercury concentrations in YOY yellow perch at each sampling location varied significantly from year to year. For the 12-year monitoring site on Sand Point Lake, values ranged from 38 ng gww-1 in 1998 to 200 ng gww -1 in 2001. For the 14-lake study, annual mean concentrations ranged by nearly a factor of 2, on average, for each lake over the three years of record. One likely factor responsible for these wide variations is that annual water-level fluctuations are strongly correlated with mercury levels in YOY perch for both data sets. ?? 2005 American Chemical Society.

  18. Factors influencing healthcare service quality

    PubMed Central

    Mosadeghrad, Ali Mohammad

    2014-01-01

    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. PMID:25114946

  19. Factors Influencing Return to Work

    PubMed Central

    Brewerton, D. A.; Daniel, J. W.

    1971-01-01

    Seventy-seven patients with severe brachial plexus injuries were interviewed two or more years later to determine their success in returning to work and the factors that had led to good or bad resettlement. For most of them these were crucial issues potentially influencing the rest of their lives. When interviewed virtually all had regular jobs in open industry, but many had endured long delays and most were working entirely one-handed. Failure of communication was regrettably common. Too often advice by doctors had been lacking, and there was evidence that the services for vocational resettlement could be improved. PMID:5123911

  20. Perched-Water Analysis Related to Deep Vadose Zone Contaminant Transport and Impact to Groundwater

    SciTech Connect

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

    2013-11-15

    Perched-water conditions have been observed in the vadose zone above a fine-grained zone that is located just a few meters above the water table beneath the B-complex at the Hanford Site. The perched water, containing elevated concentrations of uranium and technetium-99, is important to consider in evaluating the future flux of contaminated water into the groundwater. A study 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. Based on the current vertical transport pathways and large areal extent of the perched system, the evaluation was conducted using a one-dimensional (1-D) analysis. Steady-state scoping calculations showed that the perching-layer hydraulic conductivity is likely to be up to two orders of magnitude less than the base case value obtained from Hanford site literature. Numerical flow and transport simulations provided both steady-state and transient system estimates of water and contaminant behavior and were used to further refine the range of conditions consistent with current observations of perched water height and to provide estimates of future water and contaminant flux to groundwater. With a recharge rate of 6 cm/yr, representative of current disturbed surface conditions, contaminant flux from the perched water occurs over a time interval of tens of years. However, if the recharge rate is 0.35 cm/yr, representative of returning recharge to pre-Hanford Site levels, the contaminant flux into the groundwater is spread over hundreds of years. It was also demonstrated that removal of perched water by pumping would reduce the flux of water (and associated contaminants) to the groundwater, thereby impacting the long-term rate of contaminant movement to the groundwater.

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

    NASA Astrophysics Data System (ADS)

    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. (

  2. Warming alters the body shape of European perch Perca fluviatilis.

    PubMed

    Rowiński, P K; Mateos-Gonzalez, F; Sandblom, E; Jutfelt, F; Ekström, A; Sundström, L F

    2015-11-01

    The consequences of elevated temperature on body shape were investigated by comparing European perch Perca fluviatilis from the Forsmark area of the Baltic Sea to P. fluviatilis from a nearby Biotest enclosure. The Biotest is a man-made enclosure within the Baltic Sea that has received warm water from a nuclear power plant since 1980, resulting in temperatures that are elevated 5-10 °C relative to the surrounding Baltic Sea. Sampled fish ranged from young-of-the-year to 14 years. Geometric morphometrics and multivariate statistical analysis revealed significant morphological differences between individuals of P. fluviatilis from these two habitats. Most importantly, relative shape changed with size, with small individuals of P. fluviatilis from Biotest being characterized by a deeper body shape and a larger caudal peduncle than the smaller Baltic individuals. In large specimens, smaller differences were found with Biotest individuals being more slender than Baltic individuals. These results show that, in order to have a full understanding of the biological effects of elevated temperatures, studies that cover the entire size range of organisms will be important. Apart from the direct influence of temperature on growth rate and body shape, other ecological factors affected by temperature are discussed as possible contributors to the observed differences between the two populations. PMID:26440307

  3. General behaviors and perching behaviors of laying hens in cages with different colored perches.

    PubMed

    Chen, D H; Bao, J

    2012-05-01

    Color is one of the perch properties. This study was conducted to investigate the general behaviors and perching behaviors in laying hens under different group size (stocking density), and to understand the perch color (black, white or brown) preference of hens during the night. A total of 390 Hyline Brown laying hens was used, and randomly allocated to three treatments: individual group (G1), group of four hens (G4), and group of eight hens (G8), respectively. There were 30 replicates in each group. The hens in G1, G4 and G8 groups were put into the test cages in which three colored perches were simultaneously provided and allowed for four days of habituation in the new cages. Hens behaviors were recorded using cameras with infrared light sources for the following periods: 8:00 to 10:00; 14:00 to 16:00; 19:00 to 21:00; 23:30 to 0:30 on the fifth day after transferring the birds into the test cages. The behaviors of hens in every time period were collected and analyzed, and hens positions on the test perches during mid-night were recorded. The results showed that, group size (stocking density) had significant effect on most of the general behaviors of laying hens except exploring behavior. There were great differences in most of the general behaviors during different time periods. In the preference test of perch color during night, the hens showed no clear preference for white, black or brown perches. For perching behaviors, perching time and frequency of transferring from one perch to another was higher on black perches than on white or brown perches in individual groups. In G4 groups, the hens spent more time on white perches during daytime and more frequent transferring during night compared with black or brown perches. The frequency of jumping upon and down from white perches was higher in G8 groups. It can be concluded that although the group sizes in the cage significantly affected most of the general behaviors, we found that no preference of perch color was

  4. Factors influencing boar sperm cryosurvival.

    PubMed

    Roca, J; Hernández, M; Carvajal, G; Vázquez, J M; Martínez, E A

    2006-10-01

    Optimal sperm cryopreservation is a prerequisite for the sustainable commercial application of frozen-thawed boar semen for AI. Three experiments were performed to identify factors influencing variability of postthaw sperm survival among 464 boar ejaculates. Sperm-rich ejaculate fractions were cryopre-served using a standard freezing-thawing procedure for 0.5-mL plastic straws and computer-controlled freezing equipment. Postthaw sperm motility (assessed with a computer-assisted semen analysis system) and viability (simultaneously probed by flow cytometry analysis after triple-fluorescent stain), evaluated 30 and 150 min postthaw, were used to estimate the success of cryopreservation. In the first experiment, 168 unselected ejaculates (1 ejaculate/boar), from boars of 6 breeds with a wide age range (8 to 48 mo), were cryopreserved over a 12-mo period to evaluate the predictive value of boar (breed and age), semen collection, transport variables (season of ejaculate collection, interval between collections, and ejaculate temperature exposure), initial semen traits, and sperm quality before freezing on sperm survival after freezing-thawing. In Exp. 2, 4 ejaculates from each of 29 boars, preselected according to their initial semen traits and sperm quality before freezing, were collected and frozen over a 6-mo period to evaluate the influence of interboar and intraboar ejaculate variability in the survival of sperm after cryopreservation. In Exp. 3, 12 ejaculates preselected as for Exp. 2, from each of 15 boars with known good sperm cryosurvival, were collected and frozen over a 12-mo period to estimate the sustainability of sperm cryosurvival between ejaculates over time. Boar and semen collection and transport variables were not predictive of sperm cryosurvival among ejaculates. Initial semen traits and sperm quality variables observed before freezing explained 23.2 and 10.9%, respectively, of the variation in postthaw sperm motility and viability. However, more that

  5. Susceptibility of Australian Redfin Perch Perca fluviatilis Experimentally Challenged with Epizootic Hematopoietic Necrosis Virus (EHNV).

    PubMed

    Becker, Joy A; Tweedie, Alison; Gilligan, Dean; Asmus, Martin; Whittington, Richard J

    2016-06-01

    The ranavirus epizootic hematopoietic necrosis virus (EHNV) is endemic to Australia and is listed by the Office International des Epizooties. Clinical outbreaks have only been observed in wild populations of Redfin Perch Perca fluviatilis (also known as Eurasian Perch) and farmed populations of Rainbow Trout Oncorhynchus mykiss. The initial outbreaks of EHNV describe all age-classes of Redfin Perch as being susceptible and can lead to epidemic fish kills. Subsequently, experimental challenge studies using either cohabitation with the virus or injection exposures resulted in mixed susceptibilities across various age-groupings of Redfin Perch. We used an experimental bath challenge model to investigate the susceptibility of Redfin Perch collected from areas with and without a history of EHNV outbreaks. The median survival time for fish from Blowering Dam in New South Wales, a zone with a history of EHNV outbreaks, was 35 d, compared with fish from other areas, which had a median survival between 12 and 28 d postexposure. Redfin Perch from Blowering Dam demonstrated an increased mortality associated with epizootic hematopoietic necrosis up to approximately day 14 after exposure, and then there was a significantly reduced risk of mortality until the end of the trial compared with all other fish. Redfin Perch from Blowering Dam had markedly decreased susceptibility to EHNV, and less than 40% became infected following a bath challenge. In contrast, Redfin Perch from neighboring (e.g., Bethungra Dam and Tarcutta Creek) and distant water bodies (e.g., in Western Australia) with no previous history of EHNVdisplayed moderate to high susceptibility when given a bath challenge. Potential factors for the observed changes in the host-pathogen relationship include intense positive selection pressure for resistant fish following epizootic hematopoietic necrosis outbreaks and subsequent attenuation of the virulence of the virus in resistant fish. Received August 22, 2015; accepted

  6. Factors Influencing College Curriculum Choice

    ERIC Educational Resources Information Center

    Reynolds, Carl L.

    1977-01-01

    A recent study conducted at the University of Illinois on what influences college students to consider the agricultural education curriculum showed that the curriculum choice process is somewhat different for agricultural education majors than for students in the non-agricultural education group. Important influences include vocational agriculture…

  7. Assessing controls on perched saturated zones beneath the Idaho Nuclear Technology and Engineering Center, Idaho

    USGS Publications Warehouse

    Mirus, Benjamin B.; Perkins, Kim S.; Nimmo, John R.

    2011-01-01

    Waste byproducts associated with operations at the Idaho Nuclear Technology and Engineering Center (INTEC) have the potential to contaminate the eastern Snake River Plain (ESRP) aquifer. Recharge to the ESRP aquifer is controlled largely by the alternating stratigraphy of fractured volcanic rocks and sedimentary interbeds within the overlying vadose zone and by the availability of water at the surface. Beneath the INTEC facilities, localized zones of saturation perched on the sedimentary interbeds are of particular concern because they may facilitate accelerated transport of contaminants. The sources and timing of natural and anthropogenic recharge to the perched zones are poorly understood. Simple approaches for quantitative characterization of this complex, variably saturated flow system are needed to assess potential scenarios for contaminant transport under alternative remediation strategies. During 2009-2011, the U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, employed data analysis and numerical simulations with a recently developed model of preferential flow to evaluate the sources and quantity of recharge to the perched zones. Piezometer, tensiometer, temperature, precipitation, and stream-discharge data were analyzed, with particular focus on the possibility of contributions to the perched zones from snowmelt and flow in the neighboring Big Lost River (BLR). Analysis of the timing and magnitude of subsurface dynamics indicate that streamflow provides local recharge to the shallow, intermediate, and deep perched saturated zones within 150 m of the BLR; at greater distances from the BLR the influence of streamflow on recharge is unclear. Perched water-level dynamics in most wells analyzed are consistent with findings from previous geochemical analyses, which suggest that a combination of annual snowmelt and anthropogenic sources (for example, leaky pipes and drainage ditches) contribute to recharge of shallow and

  8. Factors that Influence Participation in Online Learning

    ERIC Educational Resources Information Center

    Vonderwell, Selma; Zachariah, Sajit

    2005-01-01

    This study explored what factors influenced learner participation in two sections of a graduate online course at a Midwestern university. Findings indicated that online learner participation and patterns of participation are influenced by the following factors: technology and interface characteristics, content area experience, student roles and…

  9. Estimation of Hydraulic Properties Influencing Recharge and Contaminant Transport through Complex Vadose Zones by Analyzing Perched Water Data from the 1994 Large-Scale Infiltration Test at the Idaho National Laboratory

    NASA Astrophysics Data System (ADS)

    Creasey, K. M.; Nimmo, J. R.

    2014-12-01

    Layers of strong geologic contrast within the vadose zone can control recharge and contaminant transport to underlying aquifers. Above the eastern Snake River Plain Aquifer, multiple sedimentary interbeds are interspersed between fractured basalt. These interbeds have a variety of thicknesses and hydraulic properties, and can impede water flow, which allows perched water to collect on the interbeds. The Large-Scale Infiltration Test (LSIT) of 1994 at the Idaho National Laboratory (INL) maintained a circular pond, 200 meters in diameter, at a constant head for 20 days. Monitoring wells were arranged in circles of different radii around and within the pond, and perched water levels on a major sedimentary interbed, 55 meters below ground surface, were measured over time. Data showed that water formed a mound on the interbed before seeping through the interbed. Such behavior is consistent with a hypothesis of rapid flow through the fractured basalt being impeded by the sedimentary interbed. In 2014, the USGS, in cooperation with the U.S. Department of Energy, used a modified version of a Hantush (1967) equation to model the time-dependent perched water table heights from the LSIT as a function of radial distance from the pond center. The modeled volume change between time-steps and the known inflows to the pond were used in a mass balance to estimate the time-varying volume of water seeping through the interbed. This volume of water, the height of perched water, and the interbed thickness were used in Darcy's Law to estimate the effective saturated hydraulic conductivity of the impeding interbed. Results indicate a slightly higher effective conductivity than laboratory measurements of small core samples taken from the interbed, reflecting the presence of fractures or other heterogeneities that facilitate field-scale flow through the interbed. Applied to other locations, this method can improve estimates of recharge and contaminant transport to underlying aquifers.

  10. The effect of predation on stunted and nonstunted white perch

    USGS Publications Warehouse

    Gosch, N.J.C.; Pierce, L.L.; Pope, K.L.

    2010-01-01

    Predation is widely regarded as a means to prevent or minimise the establishment of a stunted (high density of slow growing individuals) population. We investigated the effect of predation on two different white perch Morone americana populations (stunted and nonstunted) by examining the stomach contents of piscivorous fishes. White perch and gizzard shad dominated piscivore diets in Branched Oak Lake, whereas white perch dominated piscivore diets in Pawnee Lake. White perch consumed in the stunted population (Branched Oak Lake) were larger and older than white perch consumed in the nonstunted population (Pawnee Lake). Many of the consumed white perch in the stunted population were sexually mature and had the opportunity to spawn at least once. In contrast, all of the consumed white perch in the nonstunted population were sexually immature. Predation may have reinforced the stunting of white perch in Branched Oak Lake through removal of the largest, oldest individuals. ?? 2010 John Wiley & Sons A/S.

  11. Factors influencing dust suppressant effectiveness

    SciTech Connect

    Copeland, C.R.; Eisele, T.C.; Chesney, D.J.; Kawatra, S.K.

    2008-11-15

    Water sprays are a common method used to reduce particulate matter (PM) emissions. Various factors such as wettability, surface area coverage, fine particle engulfment rates, interparticle adhesion forces, suppressant penetration and suppressant longevity have all been suggested as critical factors in achieving effective PM control. However, it has not been established which of these factors are the most important. Experimental work indicated that suppressant penetration is the most critical of these factors. The length of time after application that suppressants were effective was also improved by using hygroscopic reagents that retained moisture to prevent evaporation. Maximizing suppressant penetration and improving suppressant longevity led to an average 86% reduction in PM10 concentrations in laboratory dust tower tests.

  12. Genetic factors influencing alcohol dependence

    PubMed Central

    Mayfield, R D; Harris, R A; Schuckit, M A

    2008-01-01

    Plentiful data from both animal and human studies support the importance of genetic influences in substance abuse and dependence (Bierut et al., 1998; Tsuang et al., 1998; Kendler et al., 2003). This review summarizes the evidence supporting such genetic influences, places them into perspective regarding animal and human studies, discusses the importance of both genes and environment, and highlights some specific genes of interest regarding the vulnerabilities for problems associated with alcohol use disorders. A long history of repetitive heavy use of alcohol exists across generations as well as the high prevalence of alcohol-related problems in Western societies. Moreover, the information offered here addresses the importance of more general issues regarding genetics and gene expression related to alcohol abuse and dependence. PMID:18362899

  13. Evaluating the low back biomechanics of three different office workstations: Seated, standing, and perching.

    PubMed

    Le, Peter; Marras, William S

    2016-09-01

    The objective of this study was to evaluate how different workstations may influence physical behavior in office work through motion and how that may affect spinal loads and discomfort. Twenty subjects performed a typing task in three different workstations (seated, standing, and perching) for one hour each. Measures of postural transitions, spinal loads, discomfort, and task performance were assessed in order to understand the effects of workstation interaction over time. Results indicated that standing had the most amount of motion (6-8 shifts/min), followed by perching (3-7 shifts/min), and then seating (<1 shift/min). Standing had the highest reports of discomfort and seating the least. However, spinal loads were highest in A/P shear during standing (190N posterior shear, 407N anterior shear) compared to perching (65N posterior shear, 288N anterior shear) and seating (106N posterior shear, 287 anterior shear). These loads are below the risk threshold for shear, but may still elicit a cumulative response. Perching may induce motion through supported mobility in the perching stool, whereas standing motion may be due to postural discomfort. Office workstation designs incorporating supported movement may represent a reasonable trade-off in the costs-benefits between seating and standing. PMID:27184325

  14. The Environmental Factors Influencing Attrition.

    ERIC Educational Resources Information Center

    Villella, Edward F.

    1986-01-01

    Offers an economics/business-management perspective on student attrition, focusing on the external macro-environment (including such factors as government funding of education, changing enrollment patterns, and the increased number of postsecondary institutions) and the internal micro-environment (exhibiting characteristics of intangibility,…

  15. Factors that Influence Adolescents to Smoke.

    ERIC Educational Resources Information Center

    Smith, Karen H.; Stutts, Mary Ann

    1999-01-01

    A survey of the factors that influence adolescents (n=246) to smoke found that family smoking behavior, peer pressure, and prior beliefs were more important in predicting smoking level than were advertising and antismoking information. (Author/JOW)

  16. Modeling turbidity type and intensity effects on the growth and starvation mortality of age-0 yellow perch

    USGS Publications Warehouse

    Manning, Nathan M; Bossenbroek, Jonathan M.; Mayer, Christine M.; Bunnell, David B.; Tyson, Jeff T.; Rudstam, Lars G.; Jackson, James R.

    2014-01-01

    We sought to quantify the possible population-level influence of sediment plumes and algal blooms on yellow perch (Perca flavescens), a visual predator found in systems with dynamic water clarity. We used an individual-based model (IBM), which allowed us to include variance in water clarity and the distribution of individual sizes. Our IBM was built with laboratory data showing that larval yellow perch feeding rates increased slightly as sediment turbidity level increased, but that both larval and juvenile yellow perch feeding rates decreased as phytoplankton level increased. Our IBM explained a majority of the variance in yellow perch length in data from the western and central basins of Lake Erie and Oneida Lake, with R2 values ranging from 0.611 to 0.742. Starvation mortality was size dependent, as the greatest daily mortality rates in each simulation occurred within days of each other. Our model showed that turbidity-dependent consumption rates and temperature are key components in determining growth and starvation mortality of age-0 yellow perch, linking fish production to land-based processes that influence water clarity. These results suggest the timing and persistence of sediment plumes and algal blooms can drastically alter the growth potential and starvation mortality of a yellow perch cohort.

  17. Factors influencing alginate gel biocompatibility.

    PubMed

    Tam, Susan K; Dusseault, Julie; Bilodeau, Stéphanie; Langlois, Geneviève; Hallé, Jean-Pierre; Yahia, L'Hocine

    2011-07-01

    Alginate remains the most popular polymer used for cell encapsulation, yet its biocompatibility is inconsistent. Two commercially available alginates were compared, one with 71% guluronate (HiG), and the other with 44% (IntG). Both alginates were purified, and their purities were verified. After 2 days in the peritoneal cavity of C57BL/6J mice, barium (Ba)-gel and calcium (Ca)-gel beads of IntG alginate were clean, while host cells were adhered to beads of HiG alginate. IntG gel beads, however, showed fragmentation in vivo while HiG gel beads stayed firm. The physicochemical properties of the sodium alginates and their gels were thoroughly characterized. The intrinsic viscosity of IntG alginate was 2.5-fold higher than that of HiG alginate, suggesting a greater molecular mass. X-ray photoelectron spectroscopy indicated that both alginates were similar in elemental composition, including low levels of counterions in all gels. The wettabilities of the alginates and gels were also identical, as measured by contact angles of water on dry films. Ba-gel beads of HiG alginate resisted swelling and degradation when immersed in water, much more than the other gel beads. These results suggest that the main factors contributing to the biocompatibility of gels of purified alginate are the mannuronate/guluronate content and/or intrinsic viscosity.

  18. Parent Involvement: Influencing Factors and Implications.

    ERIC Educational Resources Information Center

    Pena, Delores C.

    2000-01-01

    Investigated the involvement of Mexican American parents in their children's elementary schools. Interviews with teachers, parents, and administrators and observations of parent activities indicated that parent involvement was influenced by factors like language, parent cliques, parent education, school staff attitudes, cultural factors, and…

  19. What Factors Influence Wind Perceptions

    NASA Astrophysics Data System (ADS)

    Stein, Tatiana

    Over the last decade, wind power has emerged as a possible source of energy and has attracted the attention of homeowners and policy makers worldwide. Many technological hurdles have been overcome in the last few years that make this technology feasible and economical. The United States has added more wind power than any other type of electric generation in 2012. Depending on the location, wind resources have shown to have the potential to offer 20% of the nation's electricity; a single, large wind turbine has the capacity to produce enough electricity to power 350 homes. Throughout the development of wind turbines, however, energy companies have seen significant public opposition towards the tall white structures. The purpose of this research was to measure peoples' perceptions on wind turbine development throughout their growth, from proposal to existing phase. Three hypotheses were developed based on the participant's political affiliation, proximity and knowledge of wind turbines. To validate these hypotheses, participants were asked an array of questions regarding their perception on economic, environmental, and social impacts of wind turbines with an online service called Amazon Mechanical Turk. The responses were from residents living in the United States and required them to provide their zip code for subsequent analysis. The analysis from the data obtained suggests that participants are favorable towards wind turbine development and would be supportive of using the technology in their community. Political affiliation and proximity to the nearest wind turbine in any phase of development (proposal, construction, existing) were also analyzed to determine if they had an effect on a person's overall perception on wind turbines and their technology. From the analysis, political affiliation was seen to be an indirect factor to understanding favorability towards wind turbines; the more liberal you are, the more supportive you will be towards renewable energy use

  20. Modeling power-plant impacts on multipopulation systems: application of loop analysis to the Hudson River white perch population

    SciTech Connect

    Barnthouse, L.W.

    1981-12-01

    The white perch population of the Hudson River suffers unusually high mortality due to impingement and entrainment at power plants. The long-term consequences of this mortality for the Hudson River ecosystem depend in part on interactions between the white perch population and its prey, competitors, and predators, many of which are themselves subject to mortality at power plants. Size multipopulation models were analyzed, using a technique known as loop analysis, to determine how patterns of interaction affect population responses to stress and to identify the parameters that have the greatest influence on those responses. These theoretical results, together with information on life history and vulnerability to power plants for Hudson River fish and macroinvertebrate populations, were used to assess the likely effects of power plant mortality on the white perch population and its prey, competitors, and predators. The results suggest that effects of interactions with other populations are insufficient to offset the effects of entrainment and impingement on the Hudson River white perch population. The results also suggest that if mortality imposed by power plants does cause a substantial decline in the white perch population, then piscivore populations in the Hudson River should not be noticeably affected, a complementary increase in the abundance of competitors that are relatively invulnerable to power plants should occur, and a shift in the distribution of biomass within the white perch population toward the older age classes should occur.

  1. Remedies for a high incidence of broken eggs in furnished cages: effectiveness of increasing nest attractiveness and lowering perch height.

    PubMed

    Tuyttens, F A M; Struelens, E; Ampe, B

    2013-01-01

    Two remedial treatments to reduce the high incidence of broken eggs in the furnished cages of our experimental layer farm were investigated: lining the nest floor with artificial turf (to increase nest acceptance) and lowering perch height (to reduce the chance of egg breakage of outside-nest eggs). A 2 × 2 factorial design was used with low (7 cm) or high (24 cm) perches, and with nest floors lined with artificial turf or plastic mesh. Eight cages, each housing 8 hens initially (aged 40 to 56 wk), were used per treatment. Egg location and percentage of broken eggs were recorded. Hen position (cage floor, nest, or perch) was recorded by direct scan-sampling observations. In addition, 8 cages (4 high + 4 low) each containing 8 hens (aged 54 to 56 wk) were videorecorded to determine perch use and behavior during the light period. Data were mainly analyzed using logistic regression and mixed models with cage as the experimental unit. Nest floor material did not influence the percentage of eggs broken or laid outside the nest. The proportion of outside-nest eggs (2.6 vs. 10.6%, P = 0.004), and consequently also of total eggs (2 vs. 4.6%, P = 0.016) broken, was lower for low than high cages. Perch use increased during the observation period, more so for the high cages during the light period and the low cages during the dark period. Perch bout duration (P < 0.001), the likelihood of ending a perching bout voluntarily (P = 0.013), and time spent sitting during perching (P = 0.007) were lower in low vs. high cages. In this study, replacing plastic mesh nest floor lining with artificial turf was not an effective remedy for the already-high rate of broken eggs, but the prevalence of broken outside-nest eggs was lower in cages with low versus high perches. However, perching behavior during the light period was more disturbed in cages with low perches. PMID:23243226

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

    PubMed

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

    2016-08-01

    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 ecotoxicological studies and will facilitate their interpretation in the context of multiple stressors characteristic of field situations. PMID:27351718

  3. Cormorant predation and the population dynamics of walleye and yellow perch in Oneida Lake

    USGS Publications Warehouse

    Rudstam, L. G.; VanDeValk, A.J.; Adams, C.M.; Coleman, J.T.H.; Forney, J.L.; Richmond, M.E.

    2004-01-01

    Double-crested Cormorants (Phalacrocorax auritus) increased dramatically in North America during the 1990s, providing the opportunity to study the effects of an increase of a top predator on an existing predator-prey system. In Oneida Lake, New York, USA, Double-crested Cormorants were first observed nesting in 1984 and had increased to over 360 nesting pairs by 2000. Concomitant with this increase in piscivorous birds was a decrease in the adult walleye (Stizostedion vitreum) and yellow perch (Perca flavescens) populations. Analysis of a 40-yr data series shows higher mortality of subadults (age 1-2 yr perch and age 1-3 yr walleye) for both species in the 1990s compared to the previous three decades. Cormorant diet was investigated from 1995 to 2000 using a combination of cast pellets, regurgitants, and stomach analysis. Walleye and yellow perch were a major portion of the cormorant diet during these years (40-82% by number). The number of subadult walleye and yellow perch consumed by cormorants suggests that the increase in subadult mortality can be explained by predation from cormorants. Mean mortality rates of adult percids attributed to cormorant predation were 1.1% per year for walleye and 7.7% per year for yellow perch. Our analysis suggests that predation by cormorants on subadult percids is a major factor contributing to the decline in both the walleye and the yellow perch populations in Oneida Lake. Other ecosystem changes (zebra mussels, lower nutrient loading, decrease in alternate prey) are not likely explanations because the potential mechanisms involved are not consistent with auxiliary data from the lake and would not affect subadult mortality. The likely impact of bird predation on percid populations in Oneida Lake occurs because cormorants feed on larger fish that are beyond the size range where compensatory mechanisms are important.

  4. Effect of perches on liver health of hens.

    PubMed

    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. PMID:24812236

  5. Effect of perches on liver health of hens.

    PubMed

    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.

  6. Factors influencing recall of childhood sexual abuse.

    PubMed

    Rogers, M L

    1995-10-01

    Selective literatures providing perspective on recall of childhood sexual abuse memories are reviewed. These include known patterns of autobiographical memories in adulthood, metacognitive mechanisms, interpersonal influences, and automatic cognitive processing which can influence judgments and reports of memory recall in children and adults. Some factors in adult experience such as mood state, presence of emotional disorders, past and current relationships, and participation in psychotherapy which can influence autobiographical memory and recall of childhood events are delineated. Available studies directly exploring recovered memories of childhood abuse are considered in light of these studies. Finally, some applications to clinical work and suggestions for future research are outlined.

  7. Factors Influencing the Fatigue Strength of Materials

    NASA Technical Reports Server (NTRS)

    Bollenrath, F

    1941-01-01

    A number of factors are considered which influence the static and fatigue strength of materials under practical operating conditions as contrasted with the relations obtaining under conditions of the usual testing procedure. Such factors are interruptions in operation, periodically fluctuating stress limits and mean stresses with periodic succession of several groups and stress states, statistical changes and succession of stress limits and mean stresses, frictional corrosion at junctures, and notch effects.

  8. Factors Influencing Learning at a Community College.

    ERIC Educational Resources Information Center

    Johnson, Marvin L.

    The Walberg Educational Productivity Model theorizes that learning in its affective, behavioral, and cognitive aspects is causally influenced by factors in the areas of individual aptitude (i.e., prior achievement, age or stage of maturation, and motivation), instructional treatment (i.e., quantity of time spent in learning situations and…

  9. Factors Influencing Employee Learning in Small Businesses

    ERIC Educational Resources Information Center

    Coetzer, Alan; Perry, Martin

    2008-01-01

    Purpose: The purpose of this research is to identify key factors influencing employee learning from the perspective of owners/managers. Design/methodology/research: Data were gathered from owners/managers in a total of 27 small manufacturing and services firms through interviews and analysed using content analytic procedures. Findings: The…

  10. Technology Education Graduate Education: Factors Influencing Participation.

    ERIC Educational Resources Information Center

    Cardon, Phillip L.; Rogers, George E.

    A modified Delphi technique was used to identify the factors that positively influence technology education teachers' decision to enroll in graduate education programs and the barriers to their enrollment in advanced degree programs. Two pairs of Delphi panels were established. The doctoral panels consisted of 15 recent doctoral graduates and 30…

  11. Factors Influencing School Connectedness: Chinese Adolescents' Perspectives

    ERIC Educational Resources Information Center

    Yuen, Mantak; Lau, Patrick S. Y.; Lee, Queenie A. Y.; Gysbers, Norman C.; Chan, Raymond M. C.; Fong, Ricci W.; Chung, Y. B.; Shea, Peter M. K.

    2012-01-01

    This study explored the concept of school connectedness and the factors that may influence its development with a sample of Chinese adolescents. Six focus groups involving 52 high school students were conducted using a set of predetermined discussion topics. Results indicated that the students fully understood the notion of school connectedness…

  12. Social Factors Influencing Child Health in Ghana

    PubMed Central

    Quansah, Emmanuel; Ohene, Lilian Akorfa; Norman, Linda; Mireku, Michael Osei; Karikari, Thomas K.

    2016-01-01

    Objectives 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. Methods 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. Results 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. Conclusions 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. PMID:26745277

  13. Perch use by laying hens in a commercial aviary.

    PubMed

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-08-01

    Non-cage housing systems, such as the aviary, are being implemented by the laying hen industry, including in North America, in an attempt to improve the welfare of hens. Perches are a resource that is consistently included in aviaries. Hens are strongly motivated to perch, and perching can improve leg bone strength. However, hens may prefer elevated perches, particularly at night, and thus simply providing perches is not enough to improve welfare; they must be provided in a way that allows all hens to access them. Observations of laying hens using perches and ledges (flat, solid metal shelves to assist hens' movement between tiers) in a commercial aviary revealed variation in where hens roosted within the tiered aviary enclosure across the flock cycle (peak, mid and end of lay; P < 0.001 for all age points). Hens most often preferred roosting in the highest enclosure levels, leading to crowding on upper perches and ledges while perch space remained available on lower levels. Restricted access to preferable perches may cause frustration in hens, leading to welfare issues. Hens roosted more on perches at peak lay than mid and end lay (P < 0.001) but roosted less on ledges at peak lay than mid and end lay (P < 0.001). Additionally, more hens roosted on both perches and ledges in the 'dark' observation period compared with the number of hens roosting during the 'light' observation period (P < 0.001). Further research should look at all structural elements within the system that are used by hens for roosting, such as edges of tiers and upper wire floors, to evaluate how changes in perching preferences across the lay cycle may correlate with system design and bird-based parameters. PMID:26994206

  14. Perch use by laying hens in a commercial aviary1

    PubMed Central

    Campbell, D. L. M.; Makagon, M. M.; Swanson, J. C.; Siegford, J. M.

    2016-01-01

    Non-cage housing systems, such as the aviary, are being implemented by the laying hen industry, including in North America, in an attempt to improve the welfare of hens. Perches are a resource that is consistently included in aviaries. Hens are strongly motivated to perch, and perching can improve leg bone strength. However, hens may prefer elevated perches, particularly at night, and thus simply providing perches is not enough to improve welfare; they must be provided in a way that allows all hens to access them. Observations of laying hens using perches and ledges (flat, solid metal shelves to assist hens’ movement between tiers) in a commercial aviary revealed variation in where hens roosted within the tiered aviary enclosure across the flock cycle (peak, mid and end of lay; P < 0.001 for all age points). Hens most often preferred roosting in the highest enclosure levels, leading to crowding on upper perches and ledges while perch space remained available on lower levels. Restricted access to preferable perches may cause frustration in hens, leading to welfare issues. Hens roosted more on perches at peak lay than mid and end lay (P < 0.001) but roosted less on ledges at peak lay than mid and end lay (P < 0.001). Additionally, more hens roosted on both perches and ledges in the ‘dark’ observation period compared with the number of hens roosting during the ‘light’ observation period (P < 0.001). Further research should look at all structural elements within the system that are used by hens for roosting, such as edges of tiers and upper wire floors, to evaluate how changes in perching preferences across the lay cycle may correlate with system design and bird-based parameters. PMID:26994206

  15. Factors that influence women's dispositions toward science

    NASA Astrophysics Data System (ADS)

    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.

  16. Factors influencing the inhibition of protein kinases.

    PubMed

    Brockhoff, Marielle; Hau, Jean-Christophe; Fontana, Patrizia; Zimmermann, Catherine; Pover, Alain De; Erdmann, Dirk; Chène, Patrick

    2012-04-01

    The protein kinase field is a very active research area in the pharmaceutical industry and many activities are ongoing to identify inhibitors of these proteins. The design of new chemical entities with improved pharmacological properties requires a deeper understanding of the factors that modulate inhibitor-kinase interactions. In this report, we studied the effect of two of these factors--the magnesium ion cofactor and the protein substrate--on inhibitors of the type I insulin-like growth factor receptor. Our results show that the concentration of magnesium ion influences the potency of adenosine triphosphate (ATP) competitive inhibitors, suggesting an explanation for the observation that such compounds retain their nanomolar potency in cells despite the presence of millimolar levels of ATP. We also showed that the peptidic substrate affects the potency of these inhibitors in a different manner, suggesting that the influence of this substrate on compound potency should be taken into consideration during drug discovery.

  17. The role of vision in perching and grasping for MAVs

    NASA Astrophysics Data System (ADS)

    Thomas, Justin; Loianno, Giuseppe; Daniilidis, Kostas; Kumar, Vijay

    2016-05-01

    In this work, we provide an overview of vision-based control for perching and grasping for Micro Aerial Vehicles. We investigate perching on at, inclined, or vertical surfaces as well as visual servoing techniques for quadrotors to enable autonomous perching by hanging from cylindrical structures using only a monocular camera and an appropriate gripper. The challenges of visual servoing are discussed, and we focus on the problems of relative pose estimation, control, and trajectory planning for maneuvering a robot with respect to an object of interest. Finally, we discuss future challenges to achieve fully autonomous perching and grasping in more realistic scenarios.

  18. Field Verification of Stable Perched Groundwater in Layered Bedrock Uplands

    USGS Publications Warehouse

    Carter, J.T.; Gotkowitz, M.B.; Anderson, M.P.

    2011-01-01

    Data substantiating perched conditions in layered bedrock uplands are rare and have not been widely reported. Field observations in layered sedimentary bedrock in southwestern Wisconsin, USA, provide evidence of a stable, laterally extensive perched aquifer. Data from a densely instrumented field site show a perched aquifer in shallow dolomite, underlain by a shale-and-dolomite aquitard approximately 25 m thick, which is in turn underlain by sandstone containing a 30-m-thick unsaturated zone above a regional aquifer. Heads in water supply wells indicate that perched conditions extend at least several kilometers into hillsides, which is consistent with published modeling studies. Observations of unsaturated conditions in the sandstone over a 4-year period, historical development of the perched aquifer, and perennial flow from upland springs emanating from the shallow dolomite suggest that perched groundwater is a stable hydrogeologic feature under current climate conditions. Water-table hydrographs exhibit apparent differences in the amount and timing of recharge to the perched and regional flow systems; steep hydraulic gradients and tritium and chloride concentrations suggest there is limited hydraulic connection between the two. Recognition and characterization of perched flow systems have practical importance because their groundwater flow and transport pathways may differ significantly from those in underlying flow systems. Construction of multi-aquifer wells and groundwater withdrawal in perched systems can further alter such pathways. ?? 2010 The Author(s). Journal compilation ?? 2010 National Ground Water Association.

  19. Influence of organizational factors on safety

    SciTech Connect

    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.

  20. Factors influencing patients' dignity: A qualitative study.

    PubMed

    Manookian, Arpi; Cheraghi, Mohammad A; Nasrabadi, Alireza N

    2014-05-01

    Dignity represents the essence of nursing care; hence, nurses are professionally responsible for promoting understanding about the promotion, provision, and preservation of every patient's dignity, while considering contextual differences. The aim of this study was to explore the factors that influence, promote, or compromise patient dignity. A purposeful sample of 14 participants with hospitalization experience was chosen, and individual in-depth semi-structured interviews were conducted for data collection. Using inductive content analysis, the themes and subthemes related to factors influencing patients' dignity were explored: "persona" ("personal beliefs" and "personal characteristics"), "communication behaviors" ("verbal interaction," "body language," "compassionate behavior," and "devoting enough time"), and "staff conduct" ("professional commitment," "adequate human resources," and "staff's proficiency and competency"). The findings revealed that it is essential to expand nurses' insights and knowledge about preserving patients' dignity and the factors that influence these. Recognizing and focusing on these factors will help nurses to establish practical measures for preserving and promoting patients' dignity and providing more dignified care at the bedside.

  1. Political and economic factors influencing contraceptive uptake.

    PubMed

    Sai, F T

    1993-01-01

    International, national and local level politics influence the uptake of contraception through consensuses, laws, financial and moral support or the creation of an enabling atmosphere. Opposition to contraception generally comes from some churches and groups opposed to particular technologies. Socio-economic factors, particularly education, the health care system and the perceived or actual cost of fertility regulation as compared to benefits expected from children also powerfully influence contraceptive use. For many poor women in developing countries their powerlessness in relation to their male partners is an important obstacle.

  2. New technology turns wastes into revenue at Indiana perch farm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bell Aquaculture is vertically integrated and has closed the perch lifecycle within environmentally friendly land-based closed-containment systems. This means that Bell Aquaculture controls the broodstock, spawning, fry culture, grow-out, and 52 week per year harvest of the perch, plus the fish proc...

  3. Factors influencing public participation in biobanking.

    PubMed

    Ahram, Mamoun; Othman, Areej; Shahrouri, Manal; Mustafa, Ebtihal

    2014-04-01

    A diversity of public participation in biobanking is a highlight for the success of biobanks. It was previously reported that only two-thirds of Jordanians expressed interest in biobanking. To promote public involvement in a biobank, it is imperative to determine the aspects that influence the decision-making to participate. On the basis of a national survey involving 3196 respondents, the influence of 13 biobanking factors was assessed, including returning research results, privacy, freedom of choice, uncertainties about research, monetary and health considerations, and personal belief. Perception toward each factor was also correlated with willingness to participate in a biobank. A considerable number of respondents indicated returning research results as influential in their decision to become biobank donors. Interestingly, whereas the positive perception of availability of general results (39%) correlated with willingness to donate for biobanking, the negative view of unavailability of individualized results (47%) did not correlate with unwillingness. Religious permission of sample donation for research had the strongest positive influence (61%) and the highest correlation to participate among positively perceived factors. Unspecified research was highly indicated as a negative factor (45%), but did not correlate with unwillingness to become a biobank donor, whereas allowed withdrawal had a positive effect (31%) and correlation to contribute to biobanking. The negative perception of accessing medical information (9.5%) and re-contact (8.5%) had the strongest correlation with unwillingness to donate to a biobank. These results may provide an insight into how to formulate strategies to promote public participation in biomedical research and biobanking. PMID:23921537

  4. Factors influencing internal color of cooked meats.

    PubMed

    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. PMID:27131513

  5. Factors influencing internal color of cooked meats.

    PubMed

    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.

  6. Dermal melanin concentration of yellow perch Perca flavescens in relation to water transparency.

    PubMed

    Rheault, G; Langevin, M; Cabana, G; Glémet, H

    2015-11-01

    A positive relationship was observed between Secchi disc depth and dermal melanin concentration in yellow perch Perca flavescens sampled from 11 humic lakes located on the Canadian Shield in southern Quebec (Canada). Secchi disc depth explained 23% of the variations of dermal melanin concentration. Secchi disc depth and thus water transparency appear to have a positive influence on melanin production in the dermis of P. flavescens. PMID:26399476

  7. Dermal melanin concentration of yellow perch Perca flavescens in relation to water transparency.

    PubMed

    Rheault, G; Langevin, M; Cabana, G; Glémet, H

    2015-11-01

    A positive relationship was observed between Secchi disc depth and dermal melanin concentration in yellow perch Perca flavescens sampled from 11 humic lakes located on the Canadian Shield in southern Quebec (Canada). Secchi disc depth explained 23% of the variations of dermal melanin concentration. Secchi disc depth and thus water transparency appear to have a positive influence on melanin production in the dermis of P. flavescens.

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

    PubMed Central

    Strong, Rebecca A.; Hester, Patricia Y.; Eicher, Susan D.; Hu, Jiaying; Cheng, Heng-Wei

    2015-01-01

    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. PMID:26495988

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

    PubMed

    Strong, Rebecca A; Hester, Patricia Y; Eicher, Susan D; Hu, Jiaying; Cheng, Heng-Wei

    2015-01-01

    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. PMID:26495988

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

    PubMed

    Strong, Rebecca A; Hester, Patricia Y; Eicher, Susan D; Hu, Jiaying; Cheng, Heng-Wei

    2015-01-01

    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.

  11. Neonatal thyroid function: influence of perinatal factors.

    PubMed Central

    Franklin, R C; Carpenter, L M; O'Grady, C M

    1985-01-01

    Indices of thyroid function were measured in 229 healthy term neonates at birth and at 5, 10, and 15 days of age. Results were analysed to assess whether maternal diabetes mellitus, toxaemia of pregnancy, intrapartum fetal distress, duration of labour, method of delivery, asphyxia at birth, race, sex, birthweight, birth length, head circumference, or method of feeding influenced any index. Thyroxine, the free thyroxine index, and free thyroxine concentrations at birth correlated with birthweight. Method of delivery influenced mean thyroxine and free thyroxine index values at birth and at age 5 days. Mean values of triiodothyronine, reverse triiodothyronine, thyroxine binding globulin, and thyroid stimulating hormone were not affected by any of the perinatal factors studied. Birthweight and perhaps method of delivery should be taken into account when interpreting neonatal thyroxine parameters but determination of thyroid stimulating hormone as a screen for congenital hypothyroidism in healthy term neonates circumvents these considerations. PMID:3977386

  12. Factors influencing participation in breast cancer screening.

    PubMed

    Edgar, Lynne; Glackin, Marie; Hughes, Caroline; Rogers, Katherine Mary Ann

    Despite the efficacy of mammography and the widespread promotion of screening programmes, a significant number of eligible women still do not attend for regular breast screening. An integrative review methodology was considered the most appropriate means to critically analyse the available literature pertaining to factors which influence participation in breast cancer screening. From the extensive literature search, 12 selected core research papers met the inclusion criteria and were incorporated in the literature review. Four themes emerged from the literature which impact on participation in mammography screening: psychological and practical issues, ethnicity issues, influence of socioeconomic status and issues related to screening programmes. The recent Independent Review Panel on Breast Cancer Screening endorsed the importance of access to information which clearly communicates the harms and benefits of breast screening to enable women to make informed decisions about their health. The recommendations from the panel and others have been included in this review. PMID:24067312

  13. Factors influencing aircraft ground handling performance

    NASA Technical Reports Server (NTRS)

    Yager, T. J.

    1983-01-01

    Problems associated with aircraft ground handling operations on wet runways are discussed and major factors which influence tire/runway braking and cornering traction capability are identified including runway characteristics, tire hydroplaning, brake system anomalies, and pilot inputs. Research results from tests with instrumented ground vehicles and aircraft, and aircraft wet runway accident investigation are summarized to indicate the effects of different aircraft, tire, and runway parameters. Several promising means are described for improving tire/runway water drainage capability, brake system efficiency, and pilot training to help optimize aircraft traction performance on wet runways.

  14. [Influence of weather factors on suicidal hangings].

    PubMed

    Trepińska, Janina; Piotrowicz, Katarzyna; Bakowski, Rafał; Bolechała, Filip; Trela, Franciszek

    2005-01-01

    The paper presents a certain biometeorological problem. The evaluation of influence of weather factors on frequency of suicidal cases by hanging in the area of Cracow City during 1991-2002 was examined. Rapid changes of air pressure, air temperature, hot, sweltering and sultry days, very frosty days, days with strong or foehn wind, days with thunderstorms, fog and haze were selected as unfavourable weather factors. They give an occasion for strong psychical stress. The results of detailed investigations are next: more frequency of cases of suicide during the advance of cold fronts, rapid decreases of air pressure during hot, sweltering and sultry days, days with thunderstorms and foehn winds in the Tatra Mountains. PMID:16521499

  15. Factors influencing global antiretroviral procurement prices

    PubMed Central

    2009-01-01

    Background 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. Methods 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. Results 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. Conclusion 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

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

    PubMed

    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.

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

    PubMed

    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. PMID:26584071

  18. Factors that influence engagement in collaborative practice

    PubMed Central

    Herbert, Carol P.; Bainbridge, Lesley; Bickford, Julia; Baptiste, Susan; Brajtman, Susan; Dryden, Trish; Hall, Pippa; Risdon, Cathy; Solomon, Patricia

    2007-01-01

    OBJECTIVE To generate hypotheses regarding factors that might influence engagement in collaborative practice. DESIGN Qualitative study using in-depth interviews. SETTING Participants interviewed each other in dyads. The pairing was based upon geographical location and proximity to each other. PARTICIPANTS Eight professionals from the disciplines of medicine, nursing, occupational therapy, physical therapy, and massage therapy. METHOD Semistructured interviews, lasting 30 to 45 minutes each, were recorded and transcribed verbatim. The transcripts were read by all research team members using independent content analysis for common words, phrases, statements, or units of text for key themes. At a subsequent face-to-face meeting, the team used an iterative process of comparing and contrasting key themes until consensus was reached. The transcripts were then analyzed further for subthemes using NVivo software. MAIN FINDINGS Initial findings suggest that some common characteristics grounded in family history, school experiences, social interactions, and professional training might influence collaborative practice choices. The narrative form of the interview broke down interpersonal and interprofessional barriers, creating a new level of trust and respect that could improve professional collaboration. CONCLUSION This study suggests that life experiences from childhood into later adulthood can and do influence professional choices. PMID:17872847

  19. A kingfisher perches on a branch

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A belted kingfisher perches on a twig in the Merritt Island National Wildlife Refuge, which shares a boundary with the Kennedy Space Center. The pigeon-sized, blue-gray male is identified by the blue-gray breast band; females show a chestnut belly band. The belted kingfisher ranges throughout the United States and Canada, wintering south to Panama and the West Indies. They dive into the water for fish and may also take crabs, crayfish, salamanders, lizards, mice and insects. The 92,000-acre refuge is a habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. The marshes and open water of the refuge also provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds.

  20. Factors influencing decisions on seclusion and restraint.

    PubMed

    Larue, C; Dumais, A; Ahern, E; Bernheim, E; Mailhot, M-P

    2009-06-01

    Seclusion with or without restraint is a measure for managing aggressive or agitated clients and promoting site security, particularly in an emergency psychiatric setting. The decision to control a potentially dangerous person's behaviour by removal or seclusion seems ethically justifiable in such a setting. However, although the decisions on these restrictive measures are based on rational needs, they are also influenced by the healthcare team's perceptions of the client and by the characteristics of the team and the environment. The purpose of this paper is to set out and categorize the factors in play in aggression- and agitation-management situations as perceived by the healthcare teams, particularly the nurses. The first part of the paper deals briefly with the settings in which control measures are applied in a province in eastern Canada and the effect of such measures on patients and healthcare teams. The second part identifies the factors involved in the management of agitation and aggression behaviour. The final part discusses the current spin-offs from this knowledge as well as promising paths for further research on the factors involved. The ultimate objective is to reduce recourse to coercive measures and enhance professional practices.

  1. Factors influencing decisions on seclusion and restraint.

    PubMed

    Larue, C; Dumais, A; Ahern, E; Bernheim, E; Mailhot, M-P

    2009-06-01

    Seclusion with or without restraint is a measure for managing aggressive or agitated clients and promoting site security, particularly in an emergency psychiatric setting. The decision to control a potentially dangerous person's behaviour by removal or seclusion seems ethically justifiable in such a setting. However, although the decisions on these restrictive measures are based on rational needs, they are also influenced by the healthcare team's perceptions of the client and by the characteristics of the team and the environment. The purpose of this paper is to set out and categorize the factors in play in aggression- and agitation-management situations as perceived by the healthcare teams, particularly the nurses. The first part of the paper deals briefly with the settings in which control measures are applied in a province in eastern Canada and the effect of such measures on patients and healthcare teams. The second part identifies the factors involved in the management of agitation and aggression behaviour. The final part discusses the current spin-offs from this knowledge as well as promising paths for further research on the factors involved. The ultimate objective is to reduce recourse to coercive measures and enhance professional practices. PMID:19538600

  2. Factors influencing BMI classifications of Korean adults.

    PubMed

    Chang, Ae Kyung; Choi, Jin Yi

    2015-05-01

    [Purpose] This study aimed to identify factors influencing the BMI classifications of 3,583 Korean adults using data from the fifth Korean National Health and Nutrition Examination Survey. [Subjects and Methods] Measures included lifestyle factors, physiologic factors, perceived health state, stress, subjective body recognition, health-related quality of life, and weight control behavior. [Results] Body perception scores were lower with underweight and higher with overweight and obesity than with a healthy weight. There was a lower proportion of underweight men and a higher proportion of overweight or obese men than women. Instances of Alcohol Use Identification Scores (AUDIT) ≥ 9 were proportionately lower with underweight and more with overweight or obesity relative to an AUDIT score < 9 with healthy weight. Hemoglobin A1c and systolic blood pressure were higher with obesity than with healthy weight. The total cholesterol level was greater with overweight and obesity than with healthy weight. [Conclusion] These results suggest that obesity intervention for adults should be based on age and sex and should include drinking habits and physical activity.

  3. Experimental analysis of perching in the European starling (Sturnus vulgaris: Passeriformes; Passeres), and the automatic perching mechanism of birds.

    PubMed

    Galton, Peter M; Shepherd, Jeffrey D

    2012-04-01

    The avian automatic perching mechanism (APM) involves the automatic digital flexor mechanism (ADFM) and the digital tendon-locking mechanism (DTLM). When birds squat on a perch to sleep, the increased tendon travel distance due to flexion of the knee and ankle supposedly causes the toes to grip the perch (ADFM) and engage the DTLM so perching while sleeping involves no muscular effort. However, the knees and ankles of sleeping European starlings (Sturnus vulgaris) are only slightly flexed and, except for occasional balancing adjustments, the distal two-thirds of the toes are not flexed to grip a 6-mm-diameter perch. The cranial ankle angle (CAA) is ∼120° and the foot forms an inverted "U" that, with the mostly unflexed toes, provides a saddle-like structure so the bird balances its weight over the central pad of the foot (during day weight further back and digits actively grasp perch). In the region of the pad, the tendon sheath of many birds is unribbed, or only very slightly so, and it is always separated from the tendon of the M. flexor digitorum longus by tendons of the other toe flexor muscles. Passive leg flexion produces no toe flexion in anesthetized Starlings and only after 15-20 min, at the onset of rigor mortis, in freshly sacrificed Starlings. Anesthetized Starlings could not remain perched upon becoming unconscious (ADFM, DTLM intact). Birds whose digital flexor tendons were severed or the locking mechanism eliminated surgically (no ADFM or DTLM), so without ability to flex their toes, slept on the perch in a manner similar to unoperated Starlings (except CAA ∼90°-110°). Consequently, there is no APM or ADFM and the DTLM, although involved in lots of other activities, only acts in perching with active contraction of the digital flexor muscles. PMID:22539208

  4. Factors that can influence mentorship relationships.

    PubMed

    Hodges, Beverly

    2009-07-01

    Mentorship is an integral part of the qualified nurse role that supports learning and development. The quality of the relationship between mentor and mentee can affect learning, particularly any disparity in their expectations. A fictitious scenario is used in this article to highlight the effect of different perceptions of the mentorship relationship, with a particular focus on the nursing student and qualified nurse. Factors that can have a negative influence on mentoring include poor communication, differing expectations between mentor and mentee, lack of trust and lack of appreciation of everyday life circumstances that affects each person. The use of learning contracts, formulation of ground rules, use of information in student handbooks and discussion of the expectations of the mentor and mentee can help prevent or counteract problems in the relationship. PMID:19623801

  5. Factors influencing acrylamide formation in gingerbread.

    PubMed

    Amrein, Thomas M; Schönbächler, Barbara; Escher, Felix; Amadò, Renato

    2005-01-01

    The influence of ingredients, additives, and process conditions on the acrylamide formation in gingerbread was investigated. The sources for reducing sugars and free asparagine were identified and the effect of different baking agents on the acrylamide formation was evaluated. Ammonium hydrogencarbonate strongly enhanced the acrylamide formation, but its N-atom was not incorporated into acrylamide, nor did acrylic acid form acrylamide in gingerbread. Acrylamide concentration and browning intensity increased both with baking time and correlated with each other. The use of sodium hydrogencarbonate as baking agent reduced the acrylamide concentration by more than 60%. Free asparagine was a limiting factor for acrylamide formation, but the acrylamide content could also be lowered by replacing reducing sugars with sucrose or by adding moderate amounts of organic acids. A significant reduction of the acrylamide content in gingerbread can be achieved by using sodium hydrogencarbonate as baking agent, minimizing free asparagine, and avoiding prolonged baking.

  6. Factors influencing presence in virtual worlds.

    PubMed

    Chow, Meyrick C M

    2012-01-01

    Virtual worlds are showing potential as an effective platform for a variety of activities, including learning. The concept of presence (the sensation of "being there" in a mediated environment) has received substantial attention from the virtual reality community, and the effectiveness of virtual worlds has often been linked to the feelings of presence reported by their users. The present study examined the effects of attitude and perceived ease of use on sense of presence in Second Life, which is one of the most known and used virtual worlds. Based on data from a survey of 206 nursing students, hypotheses are empirically tested. Findings suggest that users' attitude toward using Second Life and their perceived ease of use of it have a positive effect on their sense of presence in the virtual environment. This study advances our understanding of factors influencing presence in virtual worlds.

  7. Factors influencing presence in virtual worlds

    PubMed Central

    Chow, Meyrick C.M.

    2012-01-01

    Virtual worlds are showing potential as an effective platform for a variety of activities, including learning. The concept of presence (the sensation of “being there” in a mediated environment) has received substantial attention from the virtual reality community, and the effectiveness of virtual worlds has often been linked to the feelings of presence reported by their users. The present study examined the effects of attitude and perceived ease of use on sense of presence in Second Life, which is one of the most known and used virtual worlds. Based on data from a survey of 206 nursing students, hypotheses are empirically tested. Findings suggest that users’ attitude toward using Second Life and their perceived ease of use of it have a positive effect on their sense of presence in the virtual environment. This study advances our understanding of factors influencing presence in virtual worlds. PMID:24199058

  8. Perching of Tengmalm's owl (Aegolius funereus) nestlings at the nest box entrance: effect of time of the day, age, wing length and body weight.

    PubMed

    Kouba, Marek; Bartoš, Luděk; Zárybnická, Markéta

    2014-01-01

    The behaviour of the nestlings of nocturnal cavity-nesting species has relatively rarely been studied in detail because of problems connected with use of the technical devices required to provide long-term monitoring of individuals. However, long-term observation of nestling behaviour is crucial in order to identify different types of behaviour which may be caused by sibling competition at the end of nesting period. We studied behaviour of 43 Tengmalm's owl (Aegolius funereus) nestlings at 14 nests using a camera and a chip system. The nestlings perched at the nest box entrance from an average age of 28 days from hatching (range 24-34 days) until fledging, spending around 2 hours per day here in total, in periods ranging from a few seconds to 147 min (7.6±10.9 min, mean ± SD). We found that individual duration of perching at the nest box entrance was significantly influenced by nestlings' age and wing length and that the duration of perching at the nest box entrance significantly decreased with time of night. However, during daylight hours, time of day had no effect on either probability or duration of nestlings' perching. We suggest daylight perching at the nest box entrance results from nestlings' preparation for fledging, while individuals perching here during the night may gain an advantageous position for obtaining food from the parents; another possibility at all times of day is that nestlings can reaffirm their social dominance status by monopolizing the nest box entrance.

  9. Perching of Tengmalm's Owl (Aegolius funereus) Nestlings at the Nest Box Entrance: Effect of Time of the Day, Age, Wing Length and Body Weight

    PubMed Central

    Kouba, Marek; Bartoš, Luděk; Zárybnická, Markéta

    2014-01-01

    The behaviour of the nestlings of nocturnal cavity-nesting species has relatively rarely been studied in detail because of problems connected with use of the technical devices required to provide long-term monitoring of individuals. However, long-term observation of nestling behaviour is crucial in order to identify different types of behaviour which may be caused by sibling competition at the end of nesting period. We studied behaviour of 43 Tengmalm's owl (Aegolius funereus) nestlings at 14 nests using a camera and a chip system. The nestlings perched at the nest box entrance from an average age of 28 days from hatching (range 24–34 days) until fledging, spending around 2 hours per day here in total, in periods ranging from a few seconds to 147 min (7.6±10.9 min, mean ± SD). We found that individual duration of perching at the nest box entrance was significantly influenced by nestlings' age and wing length and that the duration of perching at the nest box entrance significantly decreased with time of night. However, during daylight hours, time of day had no effect on either probability or duration of nestlings' perching. We suggest daylight perching at the nest box entrance results from nestlings' preparation for fledging, while individuals perching here during the night may gain an advantageous position for obtaining food from the parents; another possibility at all times of day is that nestlings can reaffirm their social dominance status by monopolizing the nest box entrance. PMID:24828567

  10. Influencing Factors of Thermogenic Adipose Tissue Activity

    PubMed Central

    Zhang, Guoqing; Sun, Qinghua; Liu, Cuiqing

    2016-01-01

    Obesity is an escalating public health challenge and contributes tremendously to the disease burden globally. New therapeutic strategies are required to alleviate the health impact of obesity-related metabolic dysfunction. Brown adipose tissue (BAT) is specialized for dissipating chemical energy for thermogenesis as a defense against cold environment. Intriguingly, the brown-fat like adipocytes that dispersed throughout white adipose tissue (WAT) in rodents and humans, called “brite” or “beige” adipocytes, share similar thermogenic characteristics to brown adipocytes. Recently, researchers have focused on cognition of these thermogenic adipose tissues. Some factors have been identified to regulate the development and function of thermogenic adipose tissues. Cold exposure, pharmacological conditions, and lifestyle can enhance non-shivering thermogenesis and metabolism via some mechanisms. However, environmental pollutants, such as ambient fine particulates and ozone, may impair the function of these thermogenic adipose tissues and thereby induce metabolic dysfunction. In this review, the origin, function and influencing factors of thermogenic adipose tissues were summarized and it will provide insights into identifying new therapeutic strategies for the treatment of obesity and obesity-related diseases. PMID:26903879

  11. Influencing Factors of Thermogenic Adipose Tissue Activity.

    PubMed

    Zhang, Guoqing; Sun, Qinghua; Liu, Cuiqing

    2016-01-01

    Obesity is an escalating public health challenge and contributes tremendously to the disease burden globally. New therapeutic strategies are required to alleviate the health impact of obesity-related metabolic dysfunction. Brown adipose tissue (BAT) is specialized for dissipating chemical energy for thermogenesis as a defense against cold environment. Intriguingly, the brown-fat like adipocytes that dispersed throughout white adipose tissue (WAT) in rodents and humans, called "brite" or "beige" adipocytes, share similar thermogenic characteristics to brown adipocytes. Recently, researchers have focused on cognition of these thermogenic adipose tissues. Some factors have been identified to regulate the development and function of thermogenic adipose tissues. Cold exposure, pharmacological conditions, and lifestyle can enhance non-shivering thermogenesis and metabolism via some mechanisms. However, environmental pollutants, such as ambient fine particulates and ozone, may impair the function of these thermogenic adipose tissues and thereby induce metabolic dysfunction. In this review, the origin, function and influencing factors of thermogenic adipose tissues were summarized and it will provide insights into identifying new therapeutic strategies for the treatment of obesity and obesity-related diseases. PMID:26903879

  12. Factors influencing warfarin response in hospitalized patients

    PubMed Central

    Abdel-Aziz, Mahmoud I.; Ali, Mostafa A. Sayed; Hassan, Ayman K.M.; Elfaham, Tahani H.

    2015-01-01

    The objective of this study was to investigate the influence of simultaneous factors that potentially keep patients far from achieving target INR range at discharge in hospitalized patients. Prospective cross-sectional observational study conducted at the Cardiology Department and Intensive Care Unit (ICU) of the Assiut University Hospitals. One-hundred and twenty patients were enrolled in the study from July 2013 to January 2014. Outcome measures were discharge INRs, bleeding and thromboembolic episodes. Bivariate analysis and multinomial logistic regression were conducted to determine independent risk factors that can keep patients outside target INR range. Patients who were newly initiated warfarin on hospital admission were given low initiation dose (2.8 mg ± 0.9). They were more likely to have INR values below 1.5 during hospital stay, 13 (27.7%) patients compared with 9 (12.3%) previously treated patients, respectively (p = .034). We found that the best predictors of achieving below target INR range relative to within target INR range were; shorter hospital stay periods (OR, 0.82 for every day increase [95% CI, 0.72–0.94]), being a male patient (OR, 2.86 [95% CI, 1.05–7.69]), concurrent infection (OR, 0.21 [95% CI, 0.07–0.59]) and new initiation of warfarin therapy on hospital admission (OR, 3.73 [95% CI, 1.28–10.9]). Gender, new initiation of warfarin therapy on hospital admission, shorter hospital stay periods and concurrent infection can have a significant effect on discharge INRs. Initiation of warfarin without giving loading doses increases the risk of having INRs below 1.5 during hospital stay and increases the likelihood of a patient to be discharged with INR below target range. Following warfarin dosing nomograms and careful monitoring of the effect of various factors on warfarin response should be greatly considered. PMID:26702259

  13. Factors Influencing Efficacy of Bilayered Cell Therapy

    PubMed Central

    Allam, Reynald C.; Van Driessche, Freya; Zhu, Yiliang

    2014-01-01

    Objective: Diabetic foot ulcers (DFUs) that fail to heal with standard care should be treated with advanced wound care products. Efficacy of advanced therapies is dependent on many factors. A secondary analysis of pivotal trial data for a bilayered cellular construct used in the treatment of DFU was undertaken to determine if glycemic control and other factors had an effect on time to healing. Approach: We analyzed the effect of age, gender, diabetes type, insulin usage, body mass index, smoking, initial and ending glycohemoglobin (HgbA1c), Charcot deformity, and wound area, duration, and location on likelihood of healing for wounds treated with bilayered cellular construct (BLCC). Results: In those treated with BLCC, initial wound area (cm2), age, and history of Charcot deformity were found to significantly affect healing. Neither initial HgbA1c nor change in HgbA1c was associated with healing. The bilayered product was found to be equally effective regardless of initial or change in HgbA1c levels (p-values 0.94 and 0.44, respectively). In the control group, initial HgbA1c, insulin usage, female gender, and wound location at the toes significantly influenced healing. Innovation: BLCC subgroup analysis to elucidate selection criteria allowing for targeted use of advanced products on those more likely to respond as well as direct further research into prognostic indicators for BLCC-treated patients. Conclusion: The bilayered cellular construct product remains equally effective regardless of initial or change in HgbA1c levels. Further specific research into the effect of glucose control and other factors on the effectiveness of different advanced DFU treatment products is recommended. PMID:24940555

  14. Development and evaluation of a SUAS perching system

    NASA Astrophysics Data System (ADS)

    Reynolds, Ryan

    Perching has been proposed as a possible landing technique for Small Unmanned Aircraft Systems (SUAS). The current research study develops an onboard open loop perching system for a fixed-wing SUAS and examines the impact of initial flight speed and sensor placement on the perching dynamics. A catapult launcher and modified COTS aircraft were used for the experiments, while an ultrasonic sensor on the aircraft was used to detect the perching target. Thirty tests were conducted varying the initial launch speed and ultrasonic sensor placement to see if they affected the time the aircraft reaches its maximum pitch angle, since the maximum pitch angle is the optimum perching point for the aircraft. High-speed video was analyzed to obtain flight data, along with data from an onboard inertial measuring unit. The data were analyzed using a model 1, two-way ANOVA to determine if launch speed and sensor placement affect the optimum perching point where the aircraft reaches its maximum pitch angle during the maneuver. The results show the launch speed does affect the time at which the maximum pitch angle occurs, but sensor placement does not. This means a closed loop system will need to adjust its perching distance based on its initial velocity. The sensor placement not having any noticeable effect means the ultrasonic sensor can be placed on the nose or the wing of the aircraft as needed for the design. There was also no noticeable interaction between the two variables. Aerodynamic parameters such as lift, drag, and moment coefficients were derived from the dynamic equations of motion for use in numerical simulations and dynamic perching models.

  15. "Push-Pull" Factors Influencing International Student Destination Choice.

    ERIC Educational Resources Information Center

    Mazzarol, Tim; Soutar, Geoffrey N.

    2002-01-01

    Examined factors motivating international student choice of host country. Found that economic and social factors within the home country serve to "push" students abroad, while a variety of "pull" factors influence selection of a host country. (EV)

  16. Factors Driving Biofuel Crops' Influence on Climate

    NASA Astrophysics Data System (ADS)

    Jones, A.; Torn, M. S.; Riley, W. J.; Collins, W.

    2010-12-01

    grass parameters in CLM in order to identify a smaller set of parameters that exerts the most control on climatically relevant terms such as energy and carbon fluxes. By revealing those parameters that are most and least influential in terms of climate forcing, systematic sensitivity analysis helps to prioritize the search for observational data, constrains the process of tuning parameters to limited data, and leads the way to characterizing the uncertainty in biofuel crops’ influence on climate. Furthermore, due to similarities across managed ecosystems, these results offer general insight into those plant physiological properties and management factors that must be well-characterized in order to model changes in energy and carbon fluxes resulting from human land use.

  17. Dynamics of a yellow perch population in western Lake Superior

    USGS Publications Warehouse

    Bronte, Charles R.; Selgeby, James H.; Swedberg, Donald V.

    1993-01-01

    Yellow perch Perca flavescens were sampled annually in 1973–1988 with bottom trawls in Chequamegon Bay, Lake Superior. Biomass averaged l.6 kg/hectare. Fish l–3 years old made up 64% of the biomass, whereas fish of harvestable size (≥4 years old) made up only 31% of the biomass. Year-class strength was variable among years, but a Ricker recruitment function described the relation between year-class strength and parental stock size, Age-specific mortality increased substantially as fish became sexually mature at age 4, perhaps as a result of energy depletion associated with high reproductive and maintenance costs in a suboptimal thermal environment. Yield-per-recruit analysis indicated that most of the age-specific annual mortality was due to natural causes. Natural mortality, rather than limited recruitment or fishing mortality, was the major factor controlling harvestable stock size, Regardless of the size of a year-class produced, natural mortality greatly reduced its abundance prior to maturity and recruitment to the fishable stock. This high mortality, combined with very slow growth, limits the biomass potential of the harvestable stock, and sustainable yields from this population are therefore low.

  18. Food of alewives, yellow perch, spottail shiners, trout-perch, and slimy and fourhorn sculpins in southeastern Lake Michigan

    USGS Publications Warehouse

    Wells, LaRue

    1980-01-01

    Stomachs of 1,064 alewives (Alosa pseudoharengus), 1,103 yellow perch (Perca flavescens), 246 spottail shiners (Notropis hudsonius), 288 trout-perch (Percopsis omiscomaycus), 454 slimy sculpins (Cottus cognatus), and 562 fourhorn sculpins (Myoxocephalus quadricornis) from Lake Michigan were examined for food contents. Fish were sampled primarily from March to November and nearly all were caught at the bottom in the southeastern part of the lake near Saugatuck, Michigan. Depths of capture (m) were: alewives, 5 to 110; yellow perch, 5 to 26; spottail shiners, 5 to 31; trout-perch, 9 to 46; slimy sculpins, 31 to 91; and fourhorn sculpins, 73 to 110. Alewives, particularly those less than 140 mm long, fed chiefly on zooplankton; Pontoporeia usually constituted most of the rest of the food, although Mysis and immature midges were occasionally eaten in considerable quantity. Yellow perch ate primarily Pontoporeia, fish eggs, Mysis, and crayfish; Pontoporeia was consumed most heavily by perch less than 250 mm long and those in relatively deep water, fish (mainly slimy sculpins) by those 200 mm long or longer, Mysis by those in deep water, and crayfish by those on rocky bottom. Spottail shiners fed most commonly on immature midges, Pontoporeia, zooplankton, fingernail clams, and (in July only) fish eggs; immature midges were eaten mainly by shiners in shallow water; and Pontoporeia by those in deeper areas. The diet of trout-perch was strongly dominated by Pontoporeia and immature midges. Slimy sculpins ate Pontoporeia almost exclusively. Fourhorn sculpins fed almost entirely on Mysis and Pontoporeia; Pontoporeia was particularly important in the diet of the larger fish.

  19. Food of alewives, yellow perch, spottail shiners, trout-perch, and slimy and fourhorn sculpins in southeastern Lake Michigan

    USGS Publications Warehouse

    Wells, LaRue

    1980-01-01

    Stomachs of 1, 064 alewives (Alosa pseudoharengus), 1, 103 yellow perch (Perca flavescens), 246 spottail shiners (Notropis hudsonius), 288 trout-perch (Percopsis omiscomaycus), 454 slimy sculpins (Cottus cognatus), and 562 fourhorn sculpins (Myoxocephalus quadricornis) from Lake Michigan were examined for food contents. Fish were sampled primarily from March to November and nearly all were caught at the bottom in the southeastern part of the lake near Saugatuck, Michigan. Depths of capture (m) were: alewives, 5 to 110; yellow perch, 5 to 26; spottail shiners, 5 to 31; trout-perch, 9 to 46; slimy sculpins, 31 to 91; and fourhorn sculpins, 73 to 110. Alewives, particularly those less than 140 mm long, fed chiefly on zooplankton; Pontoporeia usually constituted most of the rest of the food, although Mysis and immature midges were occasionally eaten in considerable quantity. Yellow perch ate primarily Pontoporeia, fish eggs, Mysis, and crayfish; Pontoporeiawas consumed most heavily by perch less than 250 mm long and those in relatively deep water, fish (mainly slimy sculpins) by those 200 mm long or longer, Mysis by those in deep water, and crayfish by those on rocky bottom. Spottail shiners fed most commonly on immature midges, Pontoporeia, zooplankton, fingernail clams, and (in July only) fish eggs; immature midges were eaten mainly by shiners in shallow water; and Pontoporeia by those in deeper areas. The diet of trout-perch was strongly dominated by Pontoporeia and immature midges. Slimy sculpins ate Pontoporeia almost exclusively. Fourhorn sculpins fed almost entirely on Mysis and Pontoporeia Pontoporeia was particularly important in the diet of the larger fish.

  20. Development of a bio-inspired UAV perching system

    NASA Astrophysics Data System (ADS)

    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

  1. Effect of gear selectivity on recommended allowable harvest with application to the Lake Erie yellow perch fishery

    USGS Publications Warehouse

    Madenjian, Charles P.; Ryan, Philip A.

    1995-01-01

    Because the 57-mm-mesh gill net is the predominant gear in the Lake Eric fishery for yellow perch Perca flavescens, gear selectivity is an important factor operating in that fishery. The selectivity curve for age-groups 2–6 is roughly symmetrical with peak vulnerability at age 4; younger and older perch are substantially less susceptible to the gear. The Beverton-Holt yield-per-recruit and Ricker equilibrium yield models were applied to the west-central Lake Erie yellow perch fishery to examine the effect of gear selectivity on yield-per-recruit analysis. All fish older than a specified recruitment age are assumed to he equally vulnerable in the Beverton-Holt yield-per-recruit analysis, but the Ricker equilibrium yield model can explicitly accommodate gear selectivity. Optimal fishing rate was estimated with both models, and then recommended allowable harvests were generated based on yellow perch population size estimates. Inclusion of gear selectivity in the yield-per-recruit analysis resulted in a 12% decrease in recommended allowable harvest. When skewed gear selectivity curves were investigated, gear selectivity had a still more pronounced effect on recommended allowable harvest.

  2. Factors influencing triage decisions in mental health services.

    PubMed

    Grigg, Margaret; Herrman, Helen; Harvey, Carol; Endacott, Ruth

    2007-05-01

    The aim of the study was to identify the factors influencing the timing of an assessment after contact with a triage program in a community-based area mental health service in Australia. Triage decisions apparently were influenced by several groups of factors: patient characteristics; the source and mode of the contact with triage; and to a large extent by mental health service factors including the training, supervision and support of triage workers and the perceived availability of an assessment. While demand factors such as patient characteristics influenced the triage decision, supply factors also played an important role.

  3. Factors influencing wetland use by Canada geese

    USGS Publications Warehouse

    Naugle, D.E.; Gleason, J.S.; Jenks, J.A.; Higgins, K.F.; Mammenga, P.W.; Nusser, S.M.

    1997-01-01

    Seasonal and semi-permanent wetlands in eastern South Dakota were surveyed in 1995 and 1996 to identify habitat characteristics influencing wetland use by Canada geese (Branta canadensis maxima). Position of a wetland within the landscape and its area were important landscape-scale features influencing wetland use by geese. Our delineation of potential Canada goose habitat using a wetland geographic information system indicated that distribution and area of semi-permanent wetlands likely limit Canada goose occurrence in regions outside the Prairie Coteau. Periodicity in hydrologic cycles within landscapes also may influence goose use of wetlands in eastern South Dakota.

  4. REPRODUCTIVE PHYSIOLOGY OF YELLOW PERCH (PERCA FLAVESCENS): ENVIRONMENTAL AND ENDOCRINOLOGICAL CUES

    EPA Science Inventory

    An understanding of the mechanisms involved in the regulation of reproductive processes in yellow perch is fundamental for intensive culture of this commercially important, freshwater, perciform fish. This paper describes the annual reproductive cycle of female and male perch. It...

  5. Factors Influencing Career Choice among Police Recruits

    ERIC Educational Resources Information Center

    Cole, Bryan

    2012-01-01

    This quantitative, non-experimental study examined the career choice factors of 154 (n = 154) police recruits to determine a correlation of age group generation to the five career choice factors presented in the Sibson Reward of Work Model. Law enforcement agencies faced a shortage of viable candidates to fill vacant positions. While extensive…

  6. Is Subjective Status Influenced by Psychosocial Factors?

    ERIC Educational Resources Information Center

    Lundberg, Johanna; Kristenson, Margareta

    2008-01-01

    Objective: Associations between subjective status and health are still relatively unexplored. This study aimed at testing whether subjective status is uniquely confounded by psychosocial factors compared to objective status, and what factors that may predict subjective status. Design: A cross-sectional analysis of a population-based, random sample…

  7. Botany: specialized bird perch aids cross-pollination.

    PubMed

    Anderson, Bruce; Cole, William W; Barrett, Spencer C H

    2005-05-01

    Birds may hover over or perch on flowers when feeding on nectar, and this assists cross-pollination if they then visit other plants. Here we investigate the curious sterile inflorescence axis of the South African Cape endemic 'rat's tail' plant (Babiana ringens, Iridaceae), whose function--unlike in other bird-pollinated plants--is exclusively to provide a perch for foraging birds. We find that this structure promotes the plant's mating success by causing the malachite sunbird (Nectarinia famosa), its main pollinator, to adopt a position ideal for the cross-pollination of its unusual ground-level flowers.

  8. Factors Influencing Curricular Reform; An Irish Perspective

    ERIC Educational Resources Information Center

    Ferris, Helena; Joyce, Pauline

    2015-01-01

    There are various influences and obstacles when planning an educational curriculum. The imprint of globalisation on the landscape of Irish medicine highlights the importance of delivering a diverse curriculum with international dimensions so that knowledge and skills can transfer across borders. It is also clear that medical emigration has a…

  9. 75 FR 53873 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-02

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Vessels Participating in the Rockfish Entry Level Fishery...: NMFS is prohibiting directed fishing for Pacific ocean perch for vessels participating in the rockfish... to prevent exceeding the 2010 total allowable catch (TAC) of Pacific ocean perch allocated to...

  10. Factors influencing host susceptibility to meningococcal disease.

    PubMed

    Winstanley, F P; Blackwell, C C; Weir, D M

    1985-01-01

    Host-parasite interactions influencing the development of the protective humoral immune response to Neisseria meningitidis are briefly reviewed. Possible consequences of the observed decreased titres of bactericidal activity specific for meningococcal serogroups A, B and C among patients with gonorrhoea are discussed with reference to: the epidemiology of the two diseases, the protective role of "natural" antibodies to the Neisseria species and the carriage rate of serogroupable strains of N. meningitidis among patients with gonorrhoea and a control population.

  11. Effect of bioconcentration and trophic transfer on realized exposure to oxazepam in 2 predators, the dragonfly larvae (Aeshna grandis) and the Eurasian perch (Perca fluviatilis).

    PubMed

    Heynen, Martina; Fick, Jerker; Jonsson, Micael; Klaminder, Jonatan; Brodin, Tomas

    2016-04-01

    Psychoactive substances are used worldwide and constitute one of the most common groups of pharmaceutical contaminants in surface waters. Although these pharmaceuticals are designed to be efficiently eliminated from the human body, very little is known about their trophic-transfer potential in aquatic wildlife. Therefore, the goal of the present study was to quantify and compare uptake of an anxiolytic (oxazepam) from water (bioconcentration) and via the consumption of contaminated diet (trophic transfer) in 2 common freshwater predators: Eurasian perch (Perca fluviatilis) and the dragonfly larvae Aeshna grandis. Bioconcentration and trophic transfer of oxazepam were found in both predator species. However, higher bioconcentrations were observed for perch (bioconcentration factor [BCF], 3.7) than for dragonfly larvae (BCF, 0.5). Perch also retained more oxazepam from consumed prey (41%) than dragonfly larvae (10%), whereas the relative contribution via prey consumption was 14% and 42% for perch and dragonflies, respectively. In addition, bioconcentration was negatively correlated with perch weight, indicating that exposure levels in natural contaminated environments differ between individuals of different size or between different developmental stages. Hence, trophic transfer of pharmaceuticals may indeed occur, and estimates of environmental exposures that do not consider intake via food or size-dependent bioconcentration may therefore lead to wrongful estimations of realized exposure levels in natural contaminated ecosystems. PMID:26762222

  12. Relative importance of perch and facilitative effects on nucleation in tropical woodland in Malawi

    NASA Astrophysics Data System (ADS)

    Fujita, Tomohiro

    2016-01-01

    Individual trees in open vegetation such as woodlands can act as "nuclei" for the colonization of forest tree species, which consequently lead to the formation of forest patches. This phenomenon is known as nucleation. The mechanism of nucleation is generally attributed to two factors: trees provide perches for frugivores that increase seed deposition (perch effect), and tree crowns ameliorate environmental conditions, which improves seedling establishment (facilitative effect). Few studies have attempted to distinguish the relative importance of these two factors. In this study, I separated these two effects in a woodland in northern Malawi. I chose Ficus natalensis as a potential nuclei tree because large individuals of this species are commonly located at the center of forest patches within open woodland at the study site. I monitored several environmental variables, seedling survival, seedling composition, and seed rain at three microsites: under F. natalensis, under Brachystegia floribunda (a dominant woodland species), and in open sites. Both tree species provided similar favorable conditions for the establishment of forest species compared to open sites. Thus, the survival of forest tree seedlings under F. natalensis and B. floribunda was similar, and substantially higher than seedling survival in open sites. However, communities of naturally occurring seedlings differed significantly between F. natalensis and B. floribunda. These results indicate that the facilitative effect alone cannot explain the nucleation pattern. I attribute this result to the perch effect of F. natalensis because the forest seedling species recorded under F. natalensis reportedly have small, brightly colored diaspores, which are indicative of dispersal by birds. Seed deposition of forest species under F. natalensis was significantly higher than that under B. floribunda or in open sites. My findings reinforce the idea that trees will lead to nucleation when they enhance seed

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

    USGS Publications Warehouse

    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.

  14. Environmental factors influencing growth and pubertal development.

    PubMed Central

    Delemarre-van de Waal, H A

    1993-01-01

    Postnatal growth is based on hereditary signals and environmental factors in a complex regulatory network. Each factor must be in an optimal state for normal growth of the child. Fetal conditions may also have consequences on postnatal height. Intrauterine growth retardation can be recovered postnatally, although postnatal growth remains depressed in about one-third of cases. After birth, the environment may exert either a positive or negative effect on growth. In underdeveloped countries, malnutrition plays a major role in inhibiting the growth process. Children from families of higher socioeconomic classes are taller than their coevals in the lower socioeconomic groups. Urbanization also has a positive effect on growth. Better child care is supported by sufficient food supply, appropriate health and sanitation services, and a higher level of education. Over the last century, these factors have induced a taller stature and a more rapid maturity in Europe, North America, and Australia; a phenomenon which has been referred to as "the secular trend" in growth. Recently, a secular trend has also been reported in some developing countries. Although urbanization in general appears to be associated with better conditions of living, this is not the case in the slums of South America or in Africa where rural children are better off than children living in the poor cities. This paper describes in more detail the different hereditary and environmental factors that act during the fetal period and postnatally, and which play a role in human growth and pubertal development. PMID:8243404

  15. Factors Influencing uUniversity Research Performance

    ERIC Educational Resources Information Center

    Edgar, Fiona; Geare, Alan

    2013-01-01

    This research extends our understanding of research productivity by examining features of managerial practice and culture within university departments. Adopting a robust comparative research design, capturing both interview and survey data sourced from multiple stakeholders from New Zealand universities, we seek to identify factors associated…

  16. The Influence of Noneconomic Factors on Negotiators

    ERIC Educational Resources Information Center

    Tracy, Lane

    1974-01-01

    Certain noneconomic factors in collective bargaining are directly related to the negotiator's personal inclination to settle for the new contract. In this study, the pattern of relationships between the parties, the nature of the work itself, favorable recognition, team policy, and interpersonal relationships proved to be significantly related to…

  17. Factors Influencing Recruitment in Educational Psychology

    ERIC Educational Resources Information Center

    Frederickson, Norah

    2003-01-01

    This paper reports an investigation of the factors that educational psychologists in training (EPiTs) look for when applying for jobs in educational psychology services. Relevant literature on "job attraction" is reviewed and a three-stage research process employed. This involved a focus group approach to questionnaire generation followed by…

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

    USGS Publications Warehouse

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

    1960-01-01

    Examination of the freshly dead perch revealed the presence of multiple petechiae, which were visible externally as well as in the dorsal musculature. The peritoneal cavity showed evidence of inflammation and contained a bloody ascitic fluid. A number of the dead fish were placed on ice and shipped to the Western Fish Disease Laboratory in Seattle for bacteriological studies.

  19. Mycobacterium paratuberculosis. Factors that influence mycobactin dependence.

    PubMed

    Lambrecht, R S; Collins, M T

    1992-01-01

    Mycobacterium paratuberculosis does not produce any detectable mycobactin, an iron-binding compound that is synthesized by most Mycobacterium spp. and necessary for the growth of all mycobacteria. This study examined the influence of various culture conditions on mycobactin dependence in M. paratuberculosis. Using a radiometric growth assay, we found the minimal concentration of mycobactin J necessary for growth of M. paratuberculosis to be 0.006 microM, whereas 1.2 microM (1 microgram/ml) was required for optimal growth. In media without mycobactin at iron concentrations less than or equal to 100 microM, growth of M. paratuberculosis occurred at pH 5.0, but not pH 6.8. Iron concentrations greater than 100 microM did not significantly increase growth at pH 5.0, but at pH 6.8 the growth rate increased with increasing amounts of iron reaching a rate equal to control cultures containing mycobactin. Mycobacterium paratuberculosis appeared to lose mycobactin dependence when subcultured; however, this was subsequently shown to be a result of mycobactin carried over from primary medium. Removal of this contaminating cell-wall-associated mycobactin reestablished mycobactin dependence. We conclude that mycobactin dependence must be carefully determined because it is a key test used in identification of M. paratuberculosis and may be easily influenced by media pH, iron concentration, and mycobactin carryover from primary media. PMID:1582168

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

    NASA Astrophysics Data System (ADS)

    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.

  1. Influence of hereditary factors in psychogenic disorders.

    PubMed

    Muhs, A; Schepank, H

    1995-01-01

    As part of a research project, a sample of 50 pairs of twins (21 pairs of identical twins, 16 pairs of nonidentical twins of the same sex, and 13 pairs of male-female twins, n = 100 test persons) was examined between 1963 and 1969 and recently, 20 years later, followed up. The index twins were drawn from among the patients making use of the services of an outpatient clinic; they had been diagnosed as having psychoneurotic, character-neurotic of psychosomatic disorders. The question again looked into was that of nature versus nurture: identical twins displayed significantly higher similarity with regard to both severity of their neuroses and manifestation of neurotic symptoms than did nonidentical twins. The hereditary factor proved to be of greater import for the continuing childhood neuroses than for the subsiding childhood neuroses. Yet a certain hereditary factor effect was observed for the neuroses which first manifest themselves in adulthood. Our findings indicate that the hereditary factor is not more pronounced in childhood than in adulthood; it is equally effective in adults. PMID:7480573

  2. Surface factors influencing burnout on flat heaters

    SciTech Connect

    Ramilison, J.M.; Sadasivan, P.; Lienhard, J.H. )

    1992-02-01

    Ever since Kutateladze (1951) and Zuber (1958) proposed hydrodynamic descriptions of the burnout heat flux, q{sub max}, confusion has marked the scope of their agreed-upon equation. The problem stems from Kutateladze's original correlation. The mischief in all of this is that Zuber's sketches and other aspects of his derivation suggested that he was deriving an expression applicable to a flat heater. In fact, Zuber operated under the premise - later disproved by many investigators - that the geometry did not affect burnout. His comparison of his prediction with Kutateladze's correlation did not reflect a lack of care. It reflected the conviction that geometry did not matter. As one looks more closely, surface conditions become more important than once thought. The objective of this paper is to take into account the influence of the condition of the heater surface in recreating a correlation of q{sub max} for horizontal heaters.

  3. Factors influencing the algebra ``reversal error''

    NASA Astrophysics Data System (ADS)

    Cohen, Elaine; Kanim, Stephen E.

    2005-11-01

    Given a written problem statement about a proportional relationship between two quantities, many students will place the constant of proportionality on the wrong side of the equals sign. Introductory physics is one of the first courses in which students encounter multiple-step problems that require algebraic (rather than numeric) solutions, and this "reversal error" is relatively common in student solutions to these types of problems. We describe an investigation into three possible influences on students who make this reversal error: variable symbol choice, sentence structure, and context familiarity. Our results, from a calculus-based physics course and an intermediate algebra course, show that sentence structure is the most significant of these three possibilities. However, sentence structure alone does not provide a complete explanation for the reversal error.

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

    NASA Astrophysics Data System (ADS)

    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.

  5. The effect of perch availability during pullet rearing and egg laying on the behavior of caged White Leghorn hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enriched cages, compared to conventional cages, allow egg laying strains of chickens to meet some behavioral needs, including the high motivation to perch. The objective of this study was to determine if perch availability during rearing affected perch use as adults and if perch presence affected ea...

  6. Treatment Factors That Influence Mortality in Acromegaly.

    PubMed

    McCabe, John; Ayuk, John; Sherlock, Mark

    2016-01-01

    Acromegaly is a rare condition characterized by excessive secretion of growth hormone (GH), which is almost always due to a pituitary adenoma. Acromegaly is associated with significant morbidity such as hypertension, type 2 diabetes, cardiomyopathy, obstructive sleep apnoea, malignancy and musculoskeletal abnormalities. Acromegaly has also been associated with increased mortality in several retrospective studies. This review will focus on the epidemiological data relating to mortality rates in acromegaly, the relationship between acromegaly and malignancy, the role of GH and insulin-like growth factor-I in assessing the risk of future mortality, and the impact of radiotherapy and hypopituitarism on mortality.

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

    PubMed

    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.

  8. Factors influencing the spinal motoneurons in development

    PubMed Central

    Wiese, Stefan

    2015-01-01

    The development of the spinal cord needs a concerted interaction of transcription factors activating diverse genes and signals from outside acting on the specification of the different cells. Signals have to act on the segments of the embryo as well as on the cranial-caudal axis and the dorso-ventral axis. Additionally the axons of the motoneurons have to cross the central nervous system barrier to connect to the periphery. Intensive anatomical studies have been followed by molecular characterization of the different subsets of transcription factors that are expressed by cells of the developing spinal cord. Here, intensive studies for the most important appearing cells, the motoneurons, have resulted in a good knowledge on the expression patterns of these proteins. Nonetheless motoneurons are by far not the only important cells and the concert activity of all cells besides them is necessary for the correct function and integrity of motoneurons within the spinal cord. This article will briefly summarize the different aspects on spinal cord development and focuses on the differentiation as well as the functionalization of motoneurons. PMID:26807112

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

    PubMed

    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.

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

    PubMed

    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. PMID:21476837

  11. The Influence of Societal Factors on Female Body Image.

    ERIC Educational Resources Information Center

    Monteath, Sheryl A.; McCabe, Marita P.

    1997-01-01

    Investigates the influence of societal factors on Western women's perceptions of their bodies. Finds that women typically underestimate their body size and want smaller bodies; two-fifths of women expressed negative feelings about their bodies; and that body satisfaction is best explained by societal influences, self-esteem and body mass index.…

  12. Factors Influencing the Disabled's Employment in the Competitive Labour Market.

    ERIC Educational Resources Information Center

    Mannila, Simo

    1995-01-01

    Factors influencing the job search outcomes of 1,353 Finnish individuals with disabilities were studied, focusing on age, gender, domicile, basic education, vocational training, and type of disability. Results showed that age, education, and domicile influenced outcomes, and labor market status was to some extent gender specific. (JDD)

  13. Factors influencing whether children walk to school.

    PubMed

    Su, Jason G; Jerrett, Michael; McConnell, Rob; Berhane, Kiros; Dunton, Genevieve; Shankardass, Ketan; Reynolds, Kim; Chang, Roger; Wolch, Jennifer

    2013-07-01

    Few studies have simultaneously evaluated multiple levels of influence on whether children walk to school. A large cohort of 4338 subjects from 10 communities was used to identify the determinants of walking through (1) a one-level logistic regression model for individual-level variables and (2) a two-level mixed regression model for individual and school-level variables. Walking rates were positively associated with home-to-school proximity, greater age, and living in neighborhoods characterized by lower traffic density. Greater land use mix around the home was, however, associated with lower rates of walking. Rates of walking to school were also higher amongst recipients of the Free and Reduced Price Meals Program and attendees of schools with higher percentage of English language learners. Designing schools in the same neighborhood as residential districts should be an essential urban planning strategy to reduce walking distance to school. Policy interventions are needed to encourage children from higher socioeconomic status families to participate in active travel to school and to develop walking infrastructures and other measures that protect disadvantaged children. PMID:23707968

  14. Factors Influencing Whether Children Walk to School

    PubMed Central

    Su, Jason G.; Jerrett, Michael; Mcconnell, Rob; Berhane, Kiros; Dunton, Genevieve; Shankardass, Ketan; Reynolds, Kim; Chang, Roger; Wolch, Jennifer

    2015-01-01

    Few studies have evaluated multiple levels of influence simultaneously on whether children walk to school. A large cohort of 4,338 subjects from ten communities was used to identify the determinants of walking through (1) a one-level logistic regression model for individual-level variables and (2) a two-level mixed regression model for individual and school-level variables. Walking rates were positively associated with home-to-school proximity, greater age, and living in neighborhoods characterized by lower traffic density. Greater land use mix around the home was, however, associated with lower rates of walking. Rates of walking to school were also higher amongst recipients of the Free and Reduced Price Meals Program and attendees of schools with higher percentage of English language learners. Designing schools in the same neighborhood as residential districts should be an essential urban planning strategy to reduce walking distance to school. Policy interventions are needed to encourage children from higher socioeconomic status families to participate in active travel to school and to develop walking infrastructures and other measures that protect disadvantaged children. PMID:23707968

  15. Physical factors influence for biologic systems

    NASA Astrophysics Data System (ADS)

    Piruzyan, L. A.

    2005-08-01

    Physical methods are widely spread in diagnostics and therapy of different pathologies, especially in oncology. The application of lasers occurred to be the perspective approach for combined methods application in medicine. Our work is devoted to investigation of thermal effect of focused laser beam in the model of Garding-Passi melanoma and also to the study of free radicals activity after the radiation with non-focused laser beam. The histologic alterations correlated with theoretical calculations of temperature distribution in irradiated tissue for energies 30-60 J attracted our interest. The values of maximal temperatures in depths of tissue for energies 30-60 J were carried out. In the model of permanent magnetic field (PMF) effect for mice ascites sarcoma 37 we have showed the linear dependence of tumor growth inhibition from the period of PMF treatment. Simultaneously we investigated PMF influence for free radical"s (FR) concentrations in mice organs and tissues and potentially appearing questions of PMF effect for biopotential in connection with FR formation. We have also studied the alterations of K, Na and Ca ions concentrations in ascetic fluids after animal"s PMF treatment. We revealed some reasons of biopotential generation and concluded that biopotential is not the result of specific ions gradient only but its generation can be followed by free radicals states appearance and occurrence of semi-conductivity in biostructures.

  16. Assessing accumulation and biliary excretion of naphthenic acids in yellow perch exposed to oil sands-affected waters.

    PubMed

    van den Heuvel, Michael R; Hogan, Natacha S; MacDonald, Gillian Z; Berrue, Fabrice; Young, Rozlyn F; Arens, Collin J; Kerr, Russell G; Fedorak, Phillip M

    2014-01-01

    Naphthenic acids are known to be the most prevalent group of organic compounds in oil sands tailings-associated waters. Yellow perch (Perca flavescens) were exposed for four months to oil sands-influenced waters in two experimental systems located on an oil sands lease 30 km north of Fort McMurray Alberta: the Demonstration Pond, containing oil sands tailings capped with natural surface water, and the South Bison Pond, integrating lean oil sands. Yellow perch were also sampled from three lakes: Mildred Lake that receives water from the Athabasca River, Sucker Lake, at the edge of oil sands extraction activity, and Kimowin Lake, a distant reference site. Naphthenic acids were measured in perch muscle tissue using gas chromatography-mass spectrometry (GC-MS). Bile metabolites were measured by GC-MS techniques and by high performance liquid chromatography (HPLC) with fluorescence detection at phenanthrene wavelengths. A method was developed using liquid chromatography-high resolution mass spectrometry (LC-HRMS) to evaluate naphthenic acids in bile. Tissue analysis did not show a pattern of naphthenic acids accumulation in muscle tissue consistent with known concentrations in exposed waters. Bile fluorescence and LC-HRMS methods were capable of statistically distinguishing samples originating from oil sands-influenced waters versus reference lakes. Although the GC-MS and HPLC fluorescence methods were correlated, there were no significant correlations of these methods and the LC-HRMS method. In yellow perch, naphthenic acids from oil sands sources do not concentrate in tissue at a measurable amount and are excreted through a biliary route. LC-HRMS was shown to be a highly sensitive, selective and promising technique as an indicator of exposure of biota to oil sands-derived naphthenic acids.

  17. Assessing accumulation and biliary excretion of naphthenic acids in yellow perch exposed to oil sands-affected waters.

    PubMed

    van den Heuvel, Michael R; Hogan, Natacha S; MacDonald, Gillian Z; Berrue, Fabrice; Young, Rozlyn F; Arens, Collin J; Kerr, Russell G; Fedorak, Phillip M

    2014-01-01

    Naphthenic acids are known to be the most prevalent group of organic compounds in oil sands tailings-associated waters. Yellow perch (Perca flavescens) were exposed for four months to oil sands-influenced waters in two experimental systems located on an oil sands lease 30 km north of Fort McMurray Alberta: the Demonstration Pond, containing oil sands tailings capped with natural surface water, and the South Bison Pond, integrating lean oil sands. Yellow perch were also sampled from three lakes: Mildred Lake that receives water from the Athabasca River, Sucker Lake, at the edge of oil sands extraction activity, and Kimowin Lake, a distant reference site. Naphthenic acids were measured in perch muscle tissue using gas chromatography-mass spectrometry (GC-MS). Bile metabolites were measured by GC-MS techniques and by high performance liquid chromatography (HPLC) with fluorescence detection at phenanthrene wavelengths. A method was developed using liquid chromatography-high resolution mass spectrometry (LC-HRMS) to evaluate naphthenic acids in bile. Tissue analysis did not show a pattern of naphthenic acids accumulation in muscle tissue consistent with known concentrations in exposed waters. Bile fluorescence and LC-HRMS methods were capable of statistically distinguishing samples originating from oil sands-influenced waters versus reference lakes. Although the GC-MS and HPLC fluorescence methods were correlated, there were no significant correlations of these methods and the LC-HRMS method. In yellow perch, naphthenic acids from oil sands sources do not concentrate in tissue at a measurable amount and are excreted through a biliary route. LC-HRMS was shown to be a highly sensitive, selective and promising technique as an indicator of exposure of biota to oil sands-derived naphthenic acids. PMID:24182406

  18. Factors influencing bacterial adhesion to contact lenses

    PubMed Central

    Dutta, Debarun; Willcox, Mark

    2012-01-01

    The process of any contact lens related keratitis generally starts with the adhesion of opportunistic pathogens to contact lens surface. This article focuses on identifying the factors which have been reported to affect bacterial adhesion to contact lenses. Adhesion to lenses differs between various genera/species/strains of bacteria. Pseudomonas aeruginosa, which is the predominant causative organism, adheres in the highest numbers to both hydrogel and silicone hydrogel lenses in vitro. The adhesion of this strain reaches maximum numbers within 1h in most in vitro studies and a biofilm has generally formed within 24 h of cells adhering to the lens surface. Physical and chemical properties of contact lens material affect bacterial adhesion. The water content of hydroxyethylmethacrylate (HEMA)-based lenses and their iconicity affect the ability of bacteria to adhere. The higher hydrophobicity of silicone hydrogel lenses compared to HEMA-based lenses has been implicated in the higher numbers of bacteria that can adhere to their surfaces. Lens wear has different effects on bacterial adhesion, partly due to differences between wearers, responses of bacterial strains and the ability of certain tear film proteins when bound to a lens surface to kill certain types of bacteria. PMID:22259220

  19. Factors influencing riverine fish assemblages in Massachusetts

    USGS Publications Warehouse

    Armstrong, David S.; Richards, Todd A.; Levin, Sara B.

    2011-01-01

    The U.S. Geological Survey, in cooperation with the Massachusetts Department of Conservation and Recreation, Massachusetts Department of Environmental Protection, and the Massachusetts Department of Fish and Game, conducted an investigation of fish assemblages in small- to medium-sized Massachusetts streams. The objective of this study was to determine relations between fish-assemblage characteristics and anthropogenic factors, including impervious cover and estimated flow alteration, relative to the effects of environmental factors, including physical-basin characteristics and land use. The results of this investigation supersede those of a preliminary analysis published in 2010. Fish data were obtained for 669 fish-sampling sites from the Massachusetts Division of Fisheries and Wildlife fish-community database. A review of the literature was used to select fish metrics - species richness, abundance of individual species, and abundances of species grouped on life history traits - responsive to flow alteration. The contributing areas to the fish-sampling sites were delineated and used with a geographic information system to determine a set of environmental and anthropogenic factors that were tested for use as explanatory variables in regression models. Reported and estimated withdrawals and return flows were used together with simulated unaltered streamflows to estimate altered streamflows and indicators of flow alteration for each fish-sampling site. Altered streamflows and indicators of flow alteration were calculated on the basis of methods developed in a previous U.S. Geological Survey study in which unaltered daily streamflows were simulated for a 44-year period (water years 1961-2004), and streamflow alterations were estimated by use of water-withdrawal and wastewater-return data previously reported to the State for the 2000-04 period and estimated domestic-well withdrawals and septic-system discharges. A variable selection process, conducted using principal

  20. Factors influencing phototaxis in nocturnal migrating birds.

    PubMed

    Zhao, Xuebing; Chen, Mingyan; Wu, Zhaolu; Wang, Zijiang

    2014-12-01

    Many migratory bird species fly during the night (nocturnal migrants) and have been shown to display some phototaxis to artificial light. During 2006 to 2009, we investigated phototaxis in nocturnal migrants at Jinshan Yakou in Xinping County (N23°56', E101°30'; 2400 m above sea-level), and at the Niaowang Mountain in Funing County (N23°30', E105°35'; 1400 m above sea-level), both in the Yunnan Province of Southwest China. A total of 5069 birds, representing 129 species, were captured by mist-netting and artificial light. The extent of phototaxis effect on bird migration was examined during all four seasons, three phases of the moon, and under two weather conditions (mist and wind). Data were statistically analyzed to determine the extent to which these factors may impact phototaxis of nocturnal migrants. The results point to phototaxis in birds migrating in the spring and autumn, especially in the autumn. Furthermore, migrating birds were more readily attracted to artificial lights during nights with little moonlight, mist, and a headwind. Regardless of the initial orientation in which birds flew, either following the wind or against the wind, birds would always fly against the wind when flying towards the light. This study broadens our understanding of the nocturnal bird migration, potentially resulting in improved bird ringing practices, increased awareness, and better policies regarding bird protection.

  1. Factors influencing visits to school nurses by pregnant adolescents.

    PubMed

    Chen, S P; Telleen, S; Mitchell, D R; Chen, E H

    1992-01-01

    The influence of five factors on the first visit to school nurses by pregnant adolescents and adequacy of prenatal care was analyzed. Only one factor, age of baby's father, was found to be associated with adequacy of prenatal care. PMID:1518672

  2. Factors Influencing Psychological Help Seeking in Adults: A Qualitative Study

    ERIC Educational Resources Information Center

    Topkaya, Nursel

    2015-01-01

    The aim of the current research is to identify which factors, and in what direction these factors influence adults' decisions to seek psychological help for their personal problems. The research was designed as a phenomenology model; the data was gathered through the semi-structured interview technique, which is mostly used in qualitative research…

  3. Factors Influencing Technology Planning in Developing Countries: A Literature Review

    ERIC Educational Resources Information Center

    Keengwe, Jared; Malapile, Sandy

    2014-01-01

    This article is a literature review concerning the factors that play an important role in the development of educational technology plans in the educational system of developing countries (DCs). Largely, the technology plans are influenced by factors that emanates from within the country (internal) and those outside of their borders (external).…

  4. Factors Influencing Pursuit of Higher Education: Validating a Questionnaire.

    ERIC Educational Resources Information Center

    Harris, Sandra M.

    This paper explains the process used to validate the construct validity of the Factors Influencing Pursuit of Higher Education Questionnaire. This questionnaire is a literature-based, researcher-developed instrument which gathers information on the factors thought to affect a person's decision to pursue higher education. The questionnaire includes…

  5. Psychosocial Factors Influencing Competency of Children's Statements on Sexual Trauma

    ERIC Educational Resources Information Center

    Kim, Tae Kyung; Choi, Soul; Shin, Yee Jin

    2011-01-01

    Objectives: The objectives of this study are to assess children's competence to state their traumatic experience and to determine psychosocial factors influencing the competency of children's statements, such as emotional factors of children and parents and trauma-related variables, in Korean child sex abuse victims. Methods: We enrolled 214…

  6. A Survey of Factors Influencing High School Start Times

    ERIC Educational Resources Information Center

    Wolfson, Amy R.; Carskadon, Mary A.

    2005-01-01

    The present study surveyed high school personnel regarding high school start times, factors influencing school start times, and decision making around school schedules. Surveys were analyzed from 345 secondary schools selected at random from the National Center for Educational Statistics database. Factors affecting reported start times included…

  7. Factors influencing lopinavir and atazanavir plasma concentration

    PubMed Central

    Stöhr, Wolfgang; Back, David; Dunn, David; Sabin, Caroline; Winston, Alan; Gilson, Richard; Pillay, Deenan; Hill, Teresa; Ainsworth, Jonathan; Gazzard, Brian; Leen, Clifford; Bansi, Loveleen; Fisher, Martin; Orkin, Chloe; Anderson, Jane; Johnson, Margaret; Easterbrook, Philippa; Gibbons, Sara; Khoo, Saye

    2010-01-01

    Background The protease inhibitors lopinavir and atazanavir are both recommended for treatment of HIV-infected patients. Considerable inter-individual variability in plasma concentration has been observed for both drugs. The aim of this study was to evaluate which demographic factors and concomitant drugs are associated with lopinavir and atazanavir plasma concentration. Methods Data from the Liverpool TDM (therapeutic drug monitoring) Registry were linked with the UK Collaborative HIV Cohort (CHIC) study. For each patient, the first measurement of lopinavir (twice daily) or atazanavir [once daily, ritonavir boosted (/r) or unboosted] plasma concentration was included. Linear regression was used to evaluate the association of dose, gender, age, weight, ethnicity and concomitant antiretroviral drugs or rifabutin with log-transformed drug concentration, adjusted for time since last intake. Results Data from 439 patients on lopinavir (69% 400 mg/r, 31% 533 mg/r; 3% concomitant rifabutin) and 313 on atazanavir (60% 300 mg/r, 32% 400 mg/r, 8% 400 mg) were included. Multivariable models revealed the following predictors for lopinavir concentration: weight (11% decrease per additional 10 kg; P = 0.001); dose (25% increase for 533 mg/r; P = 0.024); and rifabutin (116% increase; P < 0.001). For atazanavir the predictors were dose (compared with 300 mg/r: 40% increase for 400 mg/r, 67% decrease for 400 mg; overall P < 0.001) and efavirenz (32% decrease; P = 0.016) but not tenofovir (P = 0.54). Conclusions This analysis confirms that efavirenz decreases atazanavir concentrations, and there was a negative association of weight and lopinavir concentrations. The strong impact of rifabutin on lopinavir concentration should be studied further. PMID:19897506

  8. The role of the perch effect on the nucleation process in Mediterranean semi-arid oldfields

    NASA Astrophysics Data System (ADS)

    Pausas, Juli G.; Bonet, Andreu; Maestre, Fernando T.; Climent, Anna

    2006-05-01

    Oldfield succession in Mediterranean ecosystems has been studied extensively in mesic conditions. However, this phenomenon is still poorly understood in semi-arid Mediterranean areas, where reduced plant cover, the importance of facilitation processes and the role of abiotic factors make these environments distinct. We first test whether the carob tree ( Ceratonia siliqua) generates nucleation patterns in semi-arid oldfields, and to what extent such patterns change with abandonment age. Then we test to what extent nucleation can be explained by the perch effect. And finally, we test whether the nucleated pattern around carob trees is a source of diversity in the oldfields studied. To answer these questions we located oldfields abandoned 25 and 50 years ago (20 in each case) in the Alacant Province (SE Spain, Iberian Peninsula) on the basis of aerial photographs and personal interviews with local landowners and managers. In each oldfield woody plant density and richness were sampled on two microsites: under the carob tree and in the open field. Analysis was performed on all woody plants and by separating the species in two functional groups: fleshy-fruited (with fleshy mesocarp) and non-fleshy-fruited species. The results suggest that woody vegetation colonising abandoned C. siliqua fields in SE Spain is not randomly distributed but follows a nucleation pattern with higher plant density under the trees. However, the nucleation pattern is only significant for fleshy-fruited species, suggesting that facilitative interactions alone cannot explain the nucleation pattern and that the perch effect plays an important role. The results also show that the nucleation pattern (total plant density and density of non-fleshy-fruited plants) did not increase with abandonment age, while the perch effect (density of fleshy-fruited plants) did increase significantly. Furthermore, the results also show that the nucleation pattern is not only a loci of high plant density but also a

  9. Factors influencing nursing career choices and choice of study program.

    PubMed

    Haron, Yafa; Reicher, Sima; Riba, Shoshana

    2014-01-01

    In advance of a recruitment campaign, Israeli first-year nursing students of all ethnicities were surveyed to elucidate what factors had influenced them to make nursing their career and what sort of training track they preferred. The responses made it clear that different factors influence different groups differently. There were noticeable differences by gender, age, and ethnicity. Overall, training institutions were chosen for their closeness to the student's home but other factors also operated among particular groups, such as institutional prestige and flexible entry criteria. There was a blatant preference for academic, particularly university-sited, programs over diploma programs.

  10. Factors influencing nursing career choices and choice of study program.

    PubMed

    Haron, Yafa; Reicher, Sima; Riba, Shoshana

    2014-01-01

    In advance of a recruitment campaign, Israeli first-year nursing students of all ethnicities were surveyed to elucidate what factors had influenced them to make nursing their career and what sort of training track they preferred. The responses made it clear that different factors influence different groups differently. There were noticeable differences by gender, age, and ethnicity. Overall, training institutions were chosen for their closeness to the student's home but other factors also operated among particular groups, such as institutional prestige and flexible entry criteria. There was a blatant preference for academic, particularly university-sited, programs over diploma programs. PMID:24878405

  11. Methylmercury content of eggs in yellow perch related to maternal exposure in four Wisconsin lakes

    USGS Publications Warehouse

    Hammerschmidt, Chad R.; Wiener, James G.; Frazier, Brdaley E.; Rada, Ronald G.

    1999-01-01

    We examined the influence of maternal mercury and selected lacustrine variables on the mercury content of eggs from yellow perch (Perca flavescens). Total mercury, methylmercury, and inorganic mercury were determined in eggs and carcasses (less eggs) from three seepage lakes with a pH range of 6.1a??7.0 and a fourth lake in which pH was experimentally increased from 5.5 to 6.8 by addition of alkaline groundwater. The concentration of total mercury in eggs was strongly correlated with that in the maternal carcass. Concentrations and burdens of mercury in eggs and carcasses were inversely correlated with lake water pH, acid-neutralizing capacity, calcium, and dissolved organic carbon. In eggs containing more than 30 ng/g dry weight (4.5 ng/g wet weight) of total mercury, methylmercury averaged 91% of total mercury and ranged from 85% to 96%. Mean burdens of total mercury in individual eggs varied greatly among lakes (range, 2.3a??63 pg), and the egg mass averaged 1.9% of the whole-body burden. We conclude that exposure of the developing yellow perch embryo to methylmercury is strongly affected by maternal bioaccumulation, which can vary substantially among and within lakes; however, the toxicological significance of the observed exposure of embryos to methylmercury is unclear.

  12. Methylmercury content of eggs in yellow perch related to maternal exposure in four Wisconsin lakes

    SciTech Connect

    Hammerschmidt, C.R.; Frazier, B.E.; Rada, R.G.; Wiener, J.G.

    1999-04-01

    The authors examined the influence of maternal mercury and selected lacustrine variables on the mercury content of eggs from yellow perch (Perca flavescens). Total mercury, methylmercury, and inorganic mercury were determined in eggs and carcasses (less eggs) from three seepage lakes with a pH range of 6.1--7.0 and a fourth lake in which pH was experimentally increased from 5.5 to 6.8 by addition of alkaline groundwater. The concentration of total mercury in eggs was strongly correlated with that in the material carcass. Concentrations and burdens of mercury in eggs and carcasses were inversely correlated with lake water pH, acid-neutralizing capacity, calcium, and dissolved organic carbon. In eggs containing more than 30 ng/g dry weight of total mercury, methylmercury averaged 91% of total mercury and ranged from 85% to 96%. Mean burdens of total mercury in individual eggs varied greatly among lakes and the egg mass averaged 1.9% of the whole-body burden. The authors conclude that exposure of the developing yellow perch embryo to methylmercury is strongly affected by maternal bioaccumulation, which can vary substantially among and within lakes; however, the toxicological significance of the observed exposure of embryos to methylmercury is unclear.

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

    SciTech Connect

    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.

  14. Yellow perch larval survival studies and the potential effects of an ash storage facility in the Zekiah Swamp watershed, Wicomico River, Maryland

    SciTech Connect

    Buron, W.H.; Pinkney, A.E.; Gurley, J.

    1990-10-01

    Bioassay studies were conducted to determine if leachate from a coal ash depository was a potential factor in reducing abundance of yellow perch spawning stocks in Zekiah Swamp Run, a tributary of the Wicomico River, Maryland. In situ bioassays conducted in Zekiah Swamp Run in 1989 and 1990 using yellow perch yolk-sac larvae resulted in higher mortality upstream and downstream of the ash storage facility relative to reference stations in both years. Similar high mortality was observed at the upstream unaffected site and the downstream potentially affected site, suggesting that poor larval survival in these locations is a system-wide phenomenon. Analysis of water samples for metals, inorganic monomeric-aluminum, volatile organics, pH and measurements of physical parameters did not identify a specific cause for the high mortality observed. Surveys of the abundance and distribution of yellow perch egg strands during spring 1990 revealed that over 1,500 females spawned in a relatively restricted area in the vicinity of the fall line. In contrast to poor larval survival observed at upstream locations above the fall line, good survival was observed in bioassays conducted at a location below the fall line. Results to date are insufficient to establish the specific factors causing high mortality of larval yellow perch above the fall line. However, the ash storage site does not appear to be a contributing factor at the present time.

  15. Critical factors and paths influencing construction workers' safety risk tolerances.

    PubMed

    Wang, Jiayuan; Zou, Patrick X W; Li, Penny P

    2016-08-01

    While workers' safety risk tolerances have been regarded as a main reason for their unsafe behaviors, little is known about why different people have different risk tolerances even when confronting the same situation. The aim of this research is to identify the critical factors and paths that influence workers' safety risk tolerance and to explore how they contribute to accident causal model from a system thinking perceptive. A number of methods were carried out to analyze the data collected through interviews and questionnaire surveys. In the first and second steps of the research, factor identification, factor ranking and factor analysis were carried out, and the results show that workers' safety risk tolerance can be influenced by four groups of factors, namely: (1) personal subjective perception; (2) work knowledge and experiences; (3) work characteristics; and (4) safety management. In the third step of the research, hypothetical influencing path model was developed and tested by using structural equation modeling (SEM). It is found that the effects of external factors (safety management and work characteristics) on risk tolerance are larger than that of internal factors (personal subjective perception and work knowledge & experiences). Specifically, safety management contributes the most to workers' safety risk tolerance through its direct effect and indirect effect; while personal subjective perception comes the second and can act as an intermedia for work characteristics. This research provides an in-depth insight of workers' unsafe behaviors by depicting the contributing factors as shown in the accident causal model developed in this research. PMID:26775077

  16. Critical factors and paths influencing construction workers' safety risk tolerances.

    PubMed

    Wang, Jiayuan; Zou, Patrick X W; Li, Penny P

    2016-08-01

    While workers' safety risk tolerances have been regarded as a main reason for their unsafe behaviors, little is known about why different people have different risk tolerances even when confronting the same situation. The aim of this research is to identify the critical factors and paths that influence workers' safety risk tolerance and to explore how they contribute to accident causal model from a system thinking perceptive. A number of methods were carried out to analyze the data collected through interviews and questionnaire surveys. In the first and second steps of the research, factor identification, factor ranking and factor analysis were carried out, and the results show that workers' safety risk tolerance can be influenced by four groups of factors, namely: (1) personal subjective perception; (2) work knowledge and experiences; (3) work characteristics; and (4) safety management. In the third step of the research, hypothetical influencing path model was developed and tested by using structural equation modeling (SEM). It is found that the effects of external factors (safety management and work characteristics) on risk tolerance are larger than that of internal factors (personal subjective perception and work knowledge & experiences). Specifically, safety management contributes the most to workers' safety risk tolerance through its direct effect and indirect effect; while personal subjective perception comes the second and can act as an intermedia for work characteristics. This research provides an in-depth insight of workers' unsafe behaviors by depicting the contributing factors as shown in the accident causal model developed in this research.

  17. Habitat change in a perched dune system along Lake Superior

    USGS Publications Warehouse

    Loope, Walter L.; McEachern, A. Kathryn; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    Episodes of habitat change, driven by changes in levels of the Great Lakes, must be considered when assessing human effects upon coastal vegetation and rare species. Paleoecological studies, baseline inventories, and long-term monitoring programs within the Grand Sable Dunes, a perched-dune system along Lake Superior, provide a window on vegetation change at different spatial and temporal scales and also provide an illustrative case study.

  18. Estimating ground water recharge using flow models of perched karstic aquifers.

    PubMed

    Weiss, Menachem; Gvirtzman, Haim

    2007-01-01

    The fraction of rain that is annually recharged to ground water is a function of the transient quantities of precipitation (wet vs. dry years) as well as other meteorological and geologic factors, and thus it is very difficult to estimate. In this study, we have used long records (20 to 30 years) of precipitation and spring discharge to reconstruct the transient character of yearly recharge. These data sets were used to calibrate numerical ground water flow models on the less than 3 km(2) scale for four separate perched karstic aquifers in the Judean and Samarian Mountains of Israel. The stratification and karstic character of the local carbonate rock aquifers cause ground water to flow through discrete dissolution channels and to discharge at isolated springs. An innovative, dual-porosity approach was used where a finite-difference solution simulates flow in the rock matrix, while the karstic channels are simulated using computationally simple drains. Perched conditions are also simulated innovatively using MODFLOW by treating the bottom unsaturated layer as if it is saturated, but by assuming zero pressure head throughout the "unsaturated" layer. Best fitting between measured and computed spring hydrograph data has allowed us to develop a set of empirical functions relating measured precipitation to recharge to the aquifer. The generic methodology presented gives insight into the suspected changes in aquifer recharge rates between particularly wet or dry years.

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

    PubMed

    Jacobsen, L; Berg, S; Baktoft, H; Skov, C

    2015-03-01

    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 pelagic residency during daytime towards the littoral zone at night. In contrast, P. fluviatilis in the hypereutrophic lake were active during the entire diel cycle and were spread throughout the lake also during dark. During winter, crepuscular patterns of activity were seen in both lakes. Condition 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.

  20. Characterization of perch rhabdovirus (PRV) in farmed grayling Thymallus thymallus.

    PubMed

    Gadd, Tuija; Viljamaa-Dirks, Satu; Holopainen, Riikka; Koski, Perttu; Jakava-Viljanen, Miia

    2013-10-11

    Two Finnish fish farms experienced elevated mortality rates in farmed grayling Thymallus thymallus fry during the summer months, most typically in July. The mortalities occurred during several years and were connected with a few neurological disorders and peritonitis. Virological investigation detected an infection with an unknown rhabdovirus. Based on the entire glycoprotein (G) and partial RNA polymerase (L) gene sequences, the virus was classified as a perch rhabdovirus (PRV). Pairwise comparisons of the G and L gene regions of grayling isolates revealed that all isolates were very closely related, with 99 to 100% nucleotide identity, which suggests the same origin of infection. Phylogenetic analysis demonstrated that they were closely related to the strain isolated from perch Perca fluviatilis and sea trout Salmo trutta trutta caught from the Baltic Sea. The entire G gene sequences revealed that all Finnish grayling isolates, and both the perch and sea trout isolates, were most closely related to a PRV isolated in France in 2004. According to the partial L gene sequences, all of the Finnish grayling isolates were most closely related to the Danish isolate DK5533 from pike. The genetic analysis of entire G gene and partial L gene sequences showed that the Finnish brown trout isolate ka907_87 shared only approximately 67 and 78% identity, respectively, with our grayling isolates. The grayling isolates were also analysed by an immunofluorescence antibody test. This is the first report of a PRV causing disease in grayling in Finland.

  1. Field test of two energetic models for yellow perch

    USGS Publications Warehouse

    Schaeffer, J.S.; Haas, R.C.; Diana, J.S.; Breck, J.E.

    1999-01-01

    Field data from a population of yellow perch Perca flavescens in Saginaw Bay, Lake Huron, were used to evaluate the ability of two energetic models to predict consumption by yellow perch. Field estimates of daily ration for age-l-4 fish during May through October 1987 and 1988 were compared with independent predictions made by the Wisconsin energetic model and an energetic model developed by Karas and Thoresson. Predictions of daily ration using the Wisconsin model were lower than daily rations estimated from field data for all ages, primarily due to poor model-field agreement at temperatures above 22??C. This caused estimates of cumulative consumption from the Wisconsin model to be 25-50% lower than field estimates. Predictions of daily ration by the Karas-Thoresson model agreed with field estimates over a temperature range of 1026??C for age-1-3 yellow perch but not for older fish. Despite improvement, model predictions of cumulative consumption were 2-35% lower than field estimates. Although these tests of predicted and estimated rations may provide insight into which model produced more accurate results, it must be emphasized that field measures of daily ration are also estimates and may be in error, particularly at temperatures above 22??C where gastric evacuation rates were estimated. The Karas-Thoresson modification of the Wisconsin energetic model produced better fits to field ration data and is recommended for model applications.

  2. Factors Influencing the Intended Likelihood of Exposing Sexual Infidelity.

    PubMed

    Kruger, Daniel J; Fisher, Maryanne L; Fitzgerald, Carey J

    2015-08-01

    There is a considerable body of literature on infidelity within romantic relationships. However, there is a gap in the scientific literature on factors influencing the likelihood of uninvolved individuals exposing sexual infidelity. Therefore, we devised an exploratory study examining a wide range of potentially relevant factors. Based in part on evolutionary theory, we anticipated nine potential domains or types of influences on the likelihoods of exposing or protecting cheaters, including kinship, strong social alliances, financial support, previous relationship behaviors (including infidelity and abuse), potential relationship transitions, stronger sexual and emotional aspects of the extra-pair relationship, and disease risk. The pattern of results supported these predictions (N = 159 men, 328 women). In addition, there appeared to be a small positive bias for participants to report infidelity when provided with any additional information about the situation. Overall, this study contributes a broad initial description of factors influencing the predicted likelihood of exposing sexual infidelity and encourages further studies in this area.

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

    USGS Publications Warehouse

    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.

  4. Competition between nonindigenous ruffe and native yellow perch in laboratory studies

    USGS Publications Warehouse

    Savino, Jacqueline F.; Kolar, Cynthia S.

    1996-01-01

    The ruffe Gymnocephalus cernuus is a European percid that was accidently introduced in Duluth Harbor, Lake Superior. This nonindigenous species is closely related to yellow perch Perca flavescens, and because the two species have similar diets and habitat requirements, they are potential competitors. Laboratory studies in aquaria and pools were conducted to determine whether ruffe can compete with yellow perch for food. Ruffe had capture rates similar to those of yellow perch when food was unlimited. Ruffe spent more time than yellow perch over a feeding container before leaving it and searching again, and they also required less time to ingest (or handle) prey. However, the presence of yellow perch shortened the time ruffe spent over foraging areas when food was more limited. In addition, yellow perch were more active than ruffe, as indicated by their more frequent visits to a feeding container. Hence, the outcome of exploitative competition was not conclusive; ruffe appear to have the advantage in some behaviors, yellow perch in others. Ruffe were much more aggressive than yellow perch, and interference competition may be important in the interactions between these species. Our results indicate that ruffe might compete with native yellow perch.

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

    PubMed

    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.

  6. Ecology and population status of trout-perch (Percopsis omiscomaycus) in western Lake Erie

    USGS Publications Warehouse

    Kocovsky, Patrick; Stoneman, Andrea T.; Kraus, Richard T.

    2014-01-01

    Trout-perch Percopsis omiscomaycus is among the most abundant benthic species in Lake Erie, but comparatively little is known about its ecology. Although others have conducted extensive studies on trout-perch ecology, those efforts predated invasions of white perch Morone americana, Dreissena spp., Bythotrephes longimanus and round goby Neogobius melanostomus, suggesting the need to revisit past work. Trout-perch were sampled with bottom trawls at 56 sites during June and September 2010. We examined diets, fecundity, average annual mortality, sex ratio, and long-term population trends at sites sampled since 1961. Trout-perch abundance fluctuated periodically, with distinct shorter- (4-year) and longer-term (over period of 50 years) fluctuations. Males had higher average annual mortality than females. Both sexes were equally abundant at age 0, but females outnumbered males 4:1 by age 2. Diets of trout-perch were dominated by macroinvertebrates, particularly chironomids and Hexagenia sp. Size distributions of trout-perch eggs varied widely and exhibited multiple modes indicative of protracted batch spawning. A review of the few other studies of trout-perch revealed periodic fluctuations in sex ratio of adults, which in light of our evidence of periodicity in abundance suggests the potential for sex-ratio-mediated intrinsic population regulation. Despite the introduction of numerous invasive species in Lake Erie, trout-perch remain one of the most abundant benthic invertivores and the population is relatively stable.

  7. External and Internal Factors Influencing Happiness in Elite Collegiate Athletes

    ERIC Educational Resources Information Center

    Denny, Katherine G.; Steiner, Hans

    2009-01-01

    When under conditions of high demand and allostatic load, are happiness and satisfaction in four domains (family, friends, academics, recreation) influenced more by external or internal factors? Do student-athletes who lead exceedingly complicated lives report happiness as a function of athletic achievement or internal disposition? Stanford…

  8. Computer Visualizations: Factors that Influence Spatial Anatomy Comprehension

    ERIC Educational Resources Information Center

    Nguyen, Ngan; Nelson, Andrew J.; Wilson, Timothy D.

    2012-01-01

    Computer visualizations are increasingly common in education across a range of subject disciplines, including anatomy. Despite optimism about their educational potential, students sometime have difficulty learning from these visualizations. The purpose of this study was to explore a range of factors that influence spatial anatomy comprehension…

  9. Factors Influencing Faculty Engagement--Then, Now, and Future

    ERIC Educational Resources Information Center

    Holland, Barbara A.

    2016-01-01

    In this commentary, author Barbara Holland reflects on her 1999 "Journal of Public Service & Outreach" article, "Factors and Strategies That Influence Faculty Involvement in Public Service" (EJ589785) reprinted in this 20th anniversary issue of "Journal of Higher Education Outreach and Engagement." In the late…

  10. Factors Influencing Consent to Having Videotaped Mental Health Sessions

    ERIC Educational Resources Information Center

    Ko, Kenton; Goebert, Deborah

    2011-01-01

    Objective: The authors critically reviewed the literature regarding factors influencing consent to having videotaped mental health sessions. Methods: The authors searched the literature in PubMed, PsycINFO, Google Scholar, and Web of Science from the mid-1950s through February 2009. Results: The authors identified 27 studies, of which 19 (73%)…

  11. Factors Influencing Exemplary Science Teachers' Levels of Computer Use

    ERIC Educational Resources Information Center

    Hakverdi, Meral; Dana, Thomas M.; Swain, Colleen

    2011-01-01

    The purpose of this study was to examine exemplary science teachers' use of technology in science instruction, factors influencing their level of computer use, their level of knowledge/skills in using specific computer applications for science instruction, their use of computer-related applications/tools during their instruction, and their…

  12. Information Booklets about Cancer: Factors Influencing Patient Satisfaction and Utilisation.

    ERIC Educational Resources Information Center

    Butow, Phyllis; Brindle, Elizabeth; McConnell, David; Boakes, Robert; Tattersall, Martin

    1998-01-01

    Explored factors influencing patient satisfaction with and utilization of information booklets. Patients (N=36) rated five booklets, and strongly preferred one with a grade-eight reading level. The relationship of preference and recall was investigated. No difference between those who seek or avoid information was found. Additional findings are…

  13. Investigating Factors that Influence Item Performance on ACS Exams

    ERIC Educational Resources Information Center

    Schroeder, Jacob; Murphy, Kristen L.; Holme, Thomas A.

    2012-01-01

    General chemistry tests from the Examinations Institute of the Division of Chemical Education of the American Chemical Society have been analyzed to identify factors that may influence how individual test items perform. In this paper, issues of item order (position within a set of items that comprise a test) and answer order (position of correct…

  14. Factors Influencing Teachers' Engagement in Informal Learning Activities

    ERIC Educational Resources Information Center

    Lohman, Margaret C.

    2006-01-01

    Purpose: The purpose of this study is to examine factors influencing the engagement of public school teachers in informal learning activities. Design/methodology/approach: This study used a survey research design. Findings: Analysis of the data found that teachers rely to a greater degree on interactive than on independent informal learning…

  15. Environmental Volunteers: Factors Influencing Their Involvement in Environmental Action

    ERIC Educational Resources Information Center

    Liarakou, Georgia; Kostelou, Eleni; Gavrilakis, Costas

    2011-01-01

    The aim of the present study was to investigate the factors that influence volunteers to become involved in environmental action. The research focused on volunteers undertaking action in summer camps organised by an environmental non-governmental organisation (NGO) in Greece. The results suggest that the environmental issues addressed in volunteer…

  16. Factors that Influence Women's Technical Skill Development in Outdoor Adventure

    ERIC Educational Resources Information Center

    Warren, Karen; Loeffler, TA

    2006-01-01

    This article provides a theoretical foundation for understanding women's technical skill development (TSD) in outdoor adventure. An examination of societal and biological factors influencing women's TSD focuses on gender role socialization, sense of competence, technical conditioning, sexism, spatial ability, and risk-taking. The article suggests…

  17. Factors Influencing Student Participation in College Study Abroad Programs

    ERIC Educational Resources Information Center

    Bandyopadhyay, Soumava; Bandyopadhyay, Kakoli

    2015-01-01

    This paper proposes a theoretical framework to investigate the factors that influence student participation in college study abroad programs. The authors posit that students' general perceptions regarding the study abroad experience and their expectations of intercultural awareness from study abroad programs will impact their perceptions of…

  18. Analysis on Influence Factors of Adaptive Filter Acting on ANC

    NASA Astrophysics Data System (ADS)

    Zhang, Xiuqun; Zou, Liang; Ni, Guangkui; Wang, Xiaojun; Han, Tao; Zhao, Quanfu

    The noise problem has become more and more serious in recent years. The adaptive filter theory which is applied in ANC [1] (active noise control) has also attracted more and more attention. In this article, the basic principle and algorithm of adaptive theory are both researched. And then the influence factor that affects its covergence rate and noise reduction is also simulated.

  19. Factors that Influence Informal Learning in the Workplace

    ERIC Educational Resources Information Center

    Berg, Shelley A.; Chyung, Seung Youn

    2008-01-01

    Purpose: The purpose of this research is to investigate factors that influence informal learning in the workplace and the types of informal learning activities people engage in at work. More specifically, the research examined: the relationship between informal learning engagement and the presence of learning organization characteristics; and…

  20. Factors Influencing Federal Employee Worker Satisfaction: A Baseline Study.

    ERIC Educational Resources Information Center

    Schmidt, Wallace V.; And Others

    Utilizing data from the Federal Employee Attitude Survey, 1979, a survey was distributed to a stratified random sample of 20,000 employees to identify and analyze the factors influencing federal employee worker satisfaction. Questions on the survey ranged from demographics to personal evaluations of the work environment as recorded on a…

  1. Factors Influencing Stress, Burnout, and Retention of Secondary Teachers

    ERIC Educational Resources Information Center

    Fisher, Molly H.

    2011-01-01

    This study examines the stress, burnout, satisfaction, and preventive coping skills of nearly 400 secondary teachers to determine variables contributing to these major factors influencing teachers. Analysis of Variance (ANOVA) statistics were conducted that found the burnout levels between new and experienced teachers are significantly different,…

  2. Factors Influencing Career Choice of Management Students in India

    ERIC Educational Resources Information Center

    Agarwala, Tanuja

    2008-01-01

    Purpose: This paper aims to explore the influence of a range of factors on the career choice of management students in India. The importance of different individuals in the family and at work in making career choices among these students is also to be explored. In addition, the study seeks to address the relationship of the cultural values of…

  3. Factors that Influence Elementary Teachers Use of Computers

    ERIC Educational Resources Information Center

    Franklin, Cheryl

    2007-01-01

    The purpose of this quantitative study was to examine the ways elementary teachers use computer technology for instructional purposes and the factors that influence their use of computers. The population consisted of recent graduates from the elementary teacher preparation program at a mid-Atlantic university. Data were gathered using a survey…

  4. Social and Environmental Factors Influencing In-Prison Drug Use

    ERIC Educational Resources Information Center

    Woodall, James

    2012-01-01

    Purpose: There is a strong political imperative to regard the prison as a key social setting for health promotion, but evidence indicates that drug misuse continues to be a significant issue for many prisoners. This paper aims to examine the social and environmental factors within the setting that influence individuals' drug taking.…

  5. Factors Influencing Practical Training Quality in Iranian Agricultural Higher Education

    ERIC Educational Resources Information Center

    Mojarradi, Gholamreza; Karamidehkordi, Esmail

    2016-01-01

    This paper presents an analysis of the factors influencing the practical training quality of agricultural higher education programmes from the senior students' perspective. The study was conducted in two public universities located in the north-west of Iran using a cross-sectional survey and structured interviews with a randomised sample of 254…

  6. Consumers with Major Depressive Disorder: Factors Influencing Job Placement

    ERIC Educational Resources Information Center

    Hergenrather, Kenneth C.; Haase, Eileen; Zeglin, Robert J.; Rhodes, Scott D.

    2013-01-01

    The theory of planned behavior (TPB) was applied to study the factors that influence the intention of public rehabilitation placement professionals to place consumers with major depressive disorder (MDD) in jobs. A sample of 108 public rehabilitation placement professionals in the Mid-Atlantic region of the United States completed the MDD…

  7. Against Conventional Wisdom: Factors Influencing Hispanic Students' Reading Achievement

    ERIC Educational Resources Information Center

    Percell, Jay C.; Kaufman, Kristina

    2013-01-01

    The researchers performed a variable analysis of the 2002 Educational Longitudinal Study data investigating factors that influence students' reading scores on standardized tests. Hispanic and non-Hispanic Scores were analyzed and controlling variables were compared to determine the effect of each on both populations. Certain variables commonly…

  8. Factors Influencing Latino Participation in Community-Based Diabetes Education

    ERIC Educational Resources Information Center

    Francis, Sarah L.; Noterman, Amber; Litchfield, Ruth

    2014-01-01

    An Extension diabetes program (DP) was revised for Latinos; however, participation was limited. Factors influencing low participation rates were examined. Five Latinos interested in the DP participated in a focus group discussion. Transcripts were analyzed for themes. Preferred education programs were multi-session, local, group classes led by an…

  9. Factors Influencing Adjustment to Late-Life Divorce.

    ERIC Educational Resources Information Center

    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…

  10. Factors Influencing BI Data Collection Strategies: An Empirical Investigation

    ERIC Educational Resources Information Center

    Ramakrishnan, Thiagarajan

    2010-01-01

    The purpose of this dissertation is to examine the external factors that influence an organizations' business intelligence (BI) data collection strategy when mediated by BI attributes. In this dissertation, data warehousing strategies are used as the basis on which to frame the exploration of BI data collection strategies. The attributes include…

  11. Factors that Influence Information Systems Undergraduates to Pursue IT Certification

    ERIC Educational Resources Information Center

    Hunsinger, D. Scott; Smith, Michael A.

    2008-01-01

    We identify factors that influence the intent of undergraduate information systems majors to pursue IT certification. Previous research has revealed that IT/IS hiring managers may use certification as a job requirement or to differentiate between job candidates with similar levels of education and experience. As well, salary surveys have shown…

  12. Factors Influencing School Choice in a School District in Delaware

    ERIC Educational Resources Information Center

    Kennedy, John J., Jr.

    2012-01-01

    The purpose of this descriptive study is to examine the factors that influenced parents in a school district in Delaware when they selected a high school for their child. This study also sought to examine the sources of information that parents used. Also examined was the impact of socio-economic status in the high school selection process. A…

  13. Factors Influencing Role Behaviors by Professional Exemplars in Hospitals

    ERIC Educational Resources Information Center

    Bolding, Deborah J.

    2013-01-01

    This basic qualitative study explored factors that influenced the development of professional role behaviors of nurses, occupational and physical therapists who were characterized as exemplars in the acute hospital setting. The participants, four occupational therapists, four nurses, and four physical therapists were interviewed using a…

  14. Social Factors Influencing Participation in Sport for the Deaf.

    ERIC Educational Resources Information Center

    Stewart, David A.

    1987-01-01

    The article looks at social factors influencing participation in sport by the deaf including communication mode and value orientations of community, family, school, and peers of both the hearing and deaf world. A model for integration of the deaf into sports is offered. (DB)

  15. Multilevel Factors Influencing Maternal Stress during the First Three Years.

    ERIC Educational Resources Information Center

    Mulsow, Miriam; Caldera, Yvonne M.; Pursley, Marta; Reifman, Alan; Huston, Aletha C.

    2002-01-01

    Study applies family stress theory to the influence of personal, child, and familial factors on a mother's parenting stress during the first 3 years of her infant's life. Mother's personality was most predictive of parenting stress. Counterintuitively, mothers who were more satisfied with work or school choices were more likely to be chronically…

  16. Factors That Influence Faculty Adoption of Learning-Centered Approaches

    ERIC Educational Resources Information Center

    Blumberg, Phyllis

    2016-01-01

    This article proposes a recommended course of action for faculty development based upon Rogers' theory of Diffusion of Innovations and data collected in a study looking at the prevalence of use of learning-centered teaching practices. Specific faculty development strategies are aligned with Rogers' factors influencing decisions to adopt…

  17. Abuse of Working Children and Influencing Factors, Turkey

    ERIC Educational Resources Information Center

    Oncu, Emine; Kurt, Ahmet Oner; Esenay, Figen Isik; Ozer, Fatma

    2013-01-01

    Objective: The study was planned as the research of the kind/kinds of abuse and the factors influencing the abuse that the children under 18 who are working full-time at a workplace and enrolled in a vocational training center subjected to. Method: Questionnaires were administered to 595 apprentices who were attending a vocational training center.…

  18. Factors Influencing Secondary School Teachers' Adoption of Teaching Blogs

    ERIC Educational Resources Information Center

    Lai, Hui-Min; Chen, Chin-Pin

    2011-01-01

    Recently, there has been a significant proliferation in the number of teaching blogs; however, little has been explored about what motivates teachers to adopt teaching blogs. The purpose of this study is to find out which factors can significantly influence teacher decisions regarding their teaching blog adoption and the relative importance of…

  19. Factors Influencing the Dielectric Properties of Agricultural and Food Materials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dielectric properties of materials are defined, and the major factors that influence these properties of agricultural and food materials, namely, frequency of the applied radio-frequency or microwave electric fields, and water content, temperature, and density of the materials, are discussed on the ...

  20. What Factors Influence Vietnamese Students' Choice of University?

    ERIC Educational Resources Information Center

    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…

  1. Factors Influencing Residents' Satisfaction in Residential Aged Care

    ERIC Educational Resources Information Center

    Chou, Shu-Chiung; Boldy, Duncan P.; Lee, Andy H.

    2003-01-01

    Purpose: The aim of this study was to identify the important factors influencing residents' satisfaction in residential aged care and to provide a better understanding of their interrelationships. Design and Methods: A cross-sectional survey design was used to collect the required information, including resident satisfaction, resident dependency…

  2. Factors Influencing Knowledge Creation and Innovation in an Organisation

    ERIC Educational Resources Information Center

    Merx-Chermin, Mireille; Nijhof, Wim, J.

    2005-01-01

    Purpose: The purpose of this study is to gain a better understanding of the factors that influence the innovative power of organisations. The concept of innovation and innovative power was examined by analysing the relationship between the construct of the learning organisation, knowledge organisation and innovative organisation, and has resulted…

  3. The Influence Factors and Mechanism of Societal Risk Perception

    NASA Astrophysics Data System (ADS)

    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.

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

    NASA Astrophysics Data System (ADS)

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

    PubMed

    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.

  6. Caesium-137 in Perch in Swedish Lakes after Chernobyl-present situation, relationships and trends.

    PubMed

    Håkanson, L; Andersson, T; Nilsson, A

    1989-01-01

    The Chernobyl accident, and the general acidification of Swedish water systems, form the base for this project. The aims of the work have been to present results on the linkage between the concentration of Cs-137 in fish, lake load of Cs and lake characteristics, to give a preliminary prognosis on the recovery, and to put the results within a wider framework of environmental hazard analysis. A broad set of data on limnology, morphometry and drainage area conditions from 41 lakes were collected during 1986 and 1987. Cs-137 was determined in 1 + perch (Cs-pe, 1-year-old perch), water, material collected by sediment traps and from surficial sediments. The main results are as follows. The average value of Cs-pe for all lakes has dropped from 9800 Bq kg(-1) (wet) to 5040 between the 2 years. Generally, the decrease is between 5 and 90%. We have tested if any factor(s) could be specifically linked to this decrease-no such factors have been found. The concentrations of Cs in sediment traps have, on average, decreased by 80%. Very high correlations exist between Cs-pe and the caesium load as determined from the sediment traps. Between 1 and 10% (mean 3.9%) of the initial fall-out deposition to the drainage area was transported from land to water during June to August 1986. The variation in initial fall-out deposition explains 65-69% of the variability in Cs-pe; the degree of explanation (= coefficient of determination, r2) increases to about 85% if one also takes into account the lake water hardness and totP. A map showing with lakes likely to have 1 + perch with higher mean Cs-concentrations than 1500 Bq kg(-1) wet is presented. Between 4000 and 7000 lakes in Sweden appear to have Cs-pe higher than 1500 Bq kg(-1) wet, figures which emphasize the serious impact of the Chernobyl accident on the environmental conditions in Sweden.

  7. Factors influencing first childbearing timing decisions among men: Path analysis

    PubMed Central

    Kariman, Nourossadat; Amerian, Maliheh; Jannati, Padideh; Salmani, Fatemeh

    2016-01-01

    Background: Factors that influence men’s childbearing intentions have been relatively unexplored in the literature. Objective: This study aimed to determine the influencing factors about the first childbearing timing decisions of men. Materials and Methods: In this cross-sectional study, 300 men who were referred to private and governmental healthcare centers in Shahrood, Iran were randomly recruited from April to September 2014. Data were collected using a demographic questionnaire, the Quality of Life Questionnaire; ENRICH Marital Satisfaction Questionnaire, Synder’s Hope Scale, and the Multidimensional Scale of Perceived Social Support. Results: After removing the statistically insignificant paths, men’s age at marriage had the highest direct effect (β=0.86) on their first childbearing decision. Marital satisfaction (β=-0.09), social support (β=0.06), economic status (β=0.06), and quality of life (β=-0.08) were other effective factors on men’s first childbearing decisions. Moreover, marital satisfaction and social support had significant indirect effects on men’s childbearing decisions (β=-0.04 and -0.01, respectively). Conclusion: Many factors, including personal factors (age at marriage and quality of life), family factors (marital satisfaction), and social factors (social support), can affect men’s decision to have a child. Policymakers are hence required to develop strategies to promote the socioeconomic and family conditions of the couples and to encourage them to have as many children as they desire at an appropriate time. PMID:27738661

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

    PubMed

    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. PMID:26243016

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

    PubMed

    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.

  10. Factors influencing adherence to an emergency department national protocol.

    PubMed

    Ebben, Remco H A; Vloet, Lilian C M; de Groot, Joke Mintjes; van Achterberg, Theo

    2012-02-01

    The objective of this study was to identify factors that influence emergency nurses' adherence to an emergency department national protocol (EDNP). A survey of emergency nurses (n=200) and physicians with medical end responsibility on an emergency department (n=103) was carried out. Emergency nurses' self-reported adherence to the EDNP was 38%, 55% of the nurses and 44% of the physicians were aware of the protocol. Interference with professional autonomy, insufficient organizational support and the EDNP's applicability were indicated as barriers for adherence. The main influencing factor seems awareness. Other factors related to the individual, the organization and to protocol characteristics. Solely disseminating the EDNP is not enough to get the protocol used in clinical practice. PMID:21552130

  11. Cross-species cloning: influence of cytoplasmic factors on development.

    PubMed

    Sun, Yong-Hua; Zhu, Zuo-Yan

    2014-06-01

    It is widely accepted that the crosstalk between naive nucleus and maternal factors deposited in the egg cytoplasm before zygotic genome activation is crucial for early development. This crosstalk may also exert some influence on later development. It is interesting to clarify the relative roles of the zygotic genome and the cytoplasmic factors in development. Cross-species nuclear transfer (NT) between two distantly related species provides a unique system to study the relative role and crosstalk between egg cytoplasm and zygotic nucleus in development. In this review, we will summarize the recent progress of cross-species NT, with emphasis on the cross-species NT in fish and the influence of cytoplasmic factors on development. Finally, we conclude that the developmental process and its evolution should be interpreted in a systemic way, rather than in a way that solely focuses on the role of the nuclear genome.

  12. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    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. PMID:26409145

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    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.

  15. FACTORS INFLUENCING THE DESIGN OF BIOACCUMULATION FACTOR AND BIOTA-SEDIMENT ACCUMULATION FACTOR FIELD STUDIES

    EPA Science Inventory

    A series of modeling simulations were performed to develop an understanding of the underlying factors and principles involved in developing field sampling designs for measuring bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs. These simulations reveal...

  16. FACTORS INFLUENCING THE DESIGN OF BIOACCUMULATION FACTOR AND BIOTA-SEDIMENT ACCUMULATION FACTOR FIELD STUDIES

    EPA Science Inventory

    General guidance for designing field studies to measure bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs) is not available. To develop such guidance, a series of modeling simulations were performed to evaluate the underlying factors and principles th...

  17. Buzzcut or Fossil? Exploring the Origin of Perched Low-Relief Landscapes in the Tropics

    NASA Astrophysics Data System (ADS)

    Cunningham, M.; Stark, C. P.; Kaplan, M. R.; Schaefer, J. M.

    2014-12-01

    Throughout the tropics, high mountain regions have a "buzzcut" appearance, with low-relief spines perched high (>2500m) above deeply incised ridge-and-valley topography. Many of these mountain ranges intersect the local LGM ELA, but few studies have speculated on the role glacial erosion may have played in shaping their perched, low-relief landforms. Instead, multiple studies have invoked an abrupt increase tectonic uplift that switched the orogen from a low-relief, low erosion rate regime to a high-relief, high erosion rate mode. In this model context, perched landscapes are fossil remnants of the low-erosion rate regime, and the presence of glacial/paraglacial landforms is coincidental. However, an alternative interpretation is possible: rather than a tectonically-forced switch in erosion rate regime, low-relief spines were cut by alpine glacial erosion. To assess the influence of glacial/paraglacial processes on the formation of low-relief topography in a tropical mountain range, we conducted fieldwork at Mount Chirripó (3819m), Costa Rica. At Mount Chirripó, the estimated LGM ELA is ~3500m. River profile analysis shows a conspicuous cluster of knickpoints at ~2500m, which has been used to infer a rapid increase in regional tectonic uplift between 1-2 Ma that produced high-relief landscapes fringing ancient, low-relief landscapes. As an alternative, we hypothesize that glacial/postglacial processes acting throughout the Pleistocene played a dominant role in the formation and preservation of Mount Chirripó's low-relief spine. At Mount Chirripó, we identified glacial erosion features between 3400-3800m, including moraines, striated bedrock, glacial till, glaciofluvial outwash and post-glacial landslides. Additionally, we observed a low-sloping valley floored by angular debris at ~3100m that we interpret to be of glacial origin. We collected samples for surface exposure age dating from erratics, striated bedrock, and landslide debris boulders. Mapping of

  18. Uptake and elimination of {sup 137}Cs by climbing perch (Anabus testudineus)

    SciTech Connect

    Malek, M.A.

    1999-12-01

    This work describes the uptake and retention/biological elimination of {sup 137}Cs by climbing perch (Anabus testudineus) under laboratory conditions. The accumulated {sup 137}Cs concentration in the whole body of the fish was measured at certain intervals up to 38 d. A significant accumulation of {sub 137}Cs was not achieved by the end of the experiment. The bioaccumulation factors and the distribution of the radionuclide in edible parts of the fish were determined. The effective half-life of {sup 137}Cs in the fish species was found to be {approximately}147 d (average) for elderly and adult fishes and {approximately}300 d for younger fishes. Accumulation of {sup 137}Cs in the edible parts of the fish was found to be {approximately}77% of whole body accumulation.

  19. The Influence of Contextual and Psychosocial Factors on Handwashing.

    PubMed

    Seimetz, Elisabeth; Boyayo, Anne-Marie; Mosler, Hans-Joachim

    2016-06-01

    Even though washing hands with soap is among the most effective measures to reduce the risk of infection, handwashing rates in infrastructure-restricted settings remain seriously low. Little is known about how context alone and in interaction with psychosocial factors influence hand hygiene behavior. The aim of this article was to explore how both contextual and psychosocial factors affect handwashing practices. A cross-sectional survey was conducted with 660 caregivers of primary school children in rural Burundi. Hierarchical regression analyses revealed that household wealth, the amount of water per person, and having a designated place for washing hands were contextual factors significantly predicting handwashing frequency, whereas the contextual factors, time spent collecting water and amount of money spent on soap, were not significant predictors. The contextual factors explained about 13% of the variance of reported handwashing frequency. The addition of the psychosocial factors to the regression model resulted in a significant 41% increase of explained variation in handwashing frequency. In this final model, the amount of water was the only contextual factor that remained a significant predictor. The most important predictors were a belief of self-efficacy, planning how, when, and where to wash hands, and always remembering to do so. The findings suggest that contextual constraints might be perceived rather than actual barriers and highlight the role of psychosocial factors in understanding hygiene behaviors. PMID:27139449

  20. Succesful Lean Manufacturing Implementation: Internal Key Influencing Factors

    NASA Astrophysics Data System (ADS)

    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.

  1. [Seasonal variation and related influencing factors for tuberculosis].

    PubMed

    Zhang, Z B; Lu, Z Q; Xie, H; Duan, Q H

    2016-08-10

    Tuberculosis is recognized as a chronic respiratory infectious disease and still one of the important public health issues in the world. Douglas reported an unique seasonal pattern (summer peak) of tuberculosis, when compared with most other respiratory diseases in 1996. Since then, there had been many other researchers notified various patterns of seasonality on TB. This paper reviewed all the studies published in the last five years and analyzed the current findings on seasonal variability and influencing factors, in order to explore the risk factors to provide evidence for prevention and control strategies on tuberculosis. PMID:27539356

  2. Children's disaster reactions: the influence of family and social factors.

    PubMed

    Pfefferbaum, Betty; Jacobs, Anne K; Houston, J Brian; Griffin, Natalie

    2015-07-01

    This review examines family (demographics, parent reactions and interactions, and parenting style) and social (remote effects, disaster media coverage, exposure to secondary adversities, and social support) factors that influence children's disaster reactions. Lower family socioeconomic status, high parental stress, poor parental coping, contact with media coverage, and exposure to secondary adversities have been associated with adverse outcomes. Social support may provide protection to children in the post-disaster environment though more research is needed to clarify the effects of certain forms of social support. The interaction of the factors described in this review with culture needs further exploration.

  3. The Influence of Various Factors on the Methane Fermentation Process

    NASA Astrophysics Data System (ADS)

    Kurbanova, M. G.; Egushova, E. A.; Pozdnjakova, OG

    2015-09-01

    The article describes the stages of the methane fermentation process. The phases of methane formation are characterized. The results of the experimental data based on the study of various factors influencing the rate of biogas production and its yield are presented. Such factors as the size of the substrate particles and temperature conditions in the reactor are considered. It is revealed on the basis of experimental data which of the farm animals and poultry excrements are exposed to the most complete fermentation without special preparation. The relationship between fermentation regime, particle size of the feedstock and biogas yield is graphically presented.

  4. Metal Oxide Gas Sensors: Sensitivity and Influencing Factors

    PubMed Central

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

    2010-01-01

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

  5. Factors influencing the dielectric properties of agricultural and food products.

    PubMed

    Nelson, Stuart O; Trabelsi, Samir

    2012-01-01

    Dielectric properties of materials are defined, and the major factors that influence these properties of agricultural and food materials, namely, frequency of the applied radiofrequency or microwave electric fields, and water content, temperature, and density of the materials, are discussed on the basis of fundamental concepts. The dependence of measured dielectric properties on these factors is illustrated graphically and discussed for a number of agricultural and food products, including examples of grain, peanuts, fruit, eggs, fresh chicken meat, whey protein gel, and a macaroni and cheese preparation. General observations are provided on the nature of the variation of the dielectric properties with the major variables.

  6. Children's disaster reactions: the influence of family and social factors.

    PubMed

    Pfefferbaum, Betty; Jacobs, Anne K; Houston, J Brian; Griffin, Natalie

    2015-07-01

    This review examines family (demographics, parent reactions and interactions, and parenting style) and social (remote effects, disaster media coverage, exposure to secondary adversities, and social support) factors that influence children's disaster reactions. Lower family socioeconomic status, high parental stress, poor parental coping, contact with media coverage, and exposure to secondary adversities have been associated with adverse outcomes. Social support may provide protection to children in the post-disaster environment though more research is needed to clarify the effects of certain forms of social support. The interaction of the factors described in this review with culture needs further exploration. PMID:25980512

  7. An Integrative Review of Factors Influencing Breastfeeding in Adolescent Mothers

    PubMed Central

    Kanhadilok, Supannee; McGrath, Jacqueline M.

    2015-01-01

    ABSTRACT The purpose of this integrative review was to describe factors that influence breastfeeding behaviors in adolescent mothers. Twenty-two articles met inclusion criteria. Findings showed that most adolescent mothers intended to breastfeed during pregnancy. Yet, breastfeeding initiation ranged from 39% to 69%. Almost half of adolescent mothers stopped within 1 month. Less than 25% continued to breastfeeding behaviors to 6 months. Factors that influenced breastfeeding decisions in adolescent mothers included social and cultural norms. Personal beliefs about being a good mother were important to intention and initiation of breastfeeding. Promoting maternal competence was found to be essential to breastfeeding initiation and continuation for adolescent mothers. Support from partners and professionals also led to positive attitudes toward breastfeeding initiation and continuation. PMID:26957895

  8. Anadromous alewives, Alosa pseudoharengus, as prey for white perch, Morone americana

    USGS Publications Warehouse

    Moring, J.R.; Mink, L.H.

    2002-01-01

    The reintroduction of anadromous alewives, Alosa pseudoharengus, to their historic habitats in the inland waters of the United States and Canada, has prompted concerns about possible interactions with a popular sport fish, white perch, Morone americana. Both species are now widely distributed in northeastern North America. Diets of white perch in Lake George, Maine, U.S.A., where alewives were absent, were monitored and compared with those of white perch populations that were sympatric with anadromous alewives in two coastal Maine lakes, Biscay Pond and North Pond. In the presence of introduced alewives, the diet of adult white perch became almost exclusively juvenile alewives by late summer in ponds where both species were present. White perch that were sympatric with alewives were more piscivorus than were Lake George white perch, which primarily consumed Cladocera. Not only were alewives the principal prey item in the diet of white perch in Biscay and North ponds, but adult alewives were largely cannibalistic by August. Thus, success of reintroducing anadromous alewives in waters containing white perch may be negatively impacted by predation as well as cannibalism.

  9. Complete Genome Sequence of a Giant Sea Perch Iridovirus in Kaohsiung, Taiwan.

    PubMed

    Wen, Chiu-Ming; Hong, Jiann-Ruey

    2016-01-01

    We report here the complete genome sequence of a megalocytivirus strain, GSIV-K1, isolated from a farmed giant sea perch (Lates calcarifer) in Kaohsiung, Taiwan. GSIV-K1 causes mortality in farmed marine fish, including giant sea perch and groupers. The genome sequence is nearly identical to the genome of the orange-spotted grouper iridovirus. PMID:27125488

  10. Complete Genome Sequence of a Giant Sea Perch Iridovirus in Kaohsiung, Taiwan

    PubMed Central

    Hong, Jiann-Ruey

    2016-01-01

    We report here the complete genome sequence of a megalocytivirus strain, GSIV-K1, isolated from a farmed giant sea perch (Lates calcarifer) in Kaohsiung, Taiwan. GSIV-K1 causes mortality in farmed marine fish, including giant sea perch and groupers. The genome sequence is nearly identical to the genome of the orange-spotted grouper iridovirus. PMID:27125488

  11. Scaling the sublethal effects of methylmercury to yellow perchs population dynamics using adverse outcome pathway framework

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study sought to evaluate the effects of environmentally relevant dietary MeHg exposures on adult female yellow perch (Perca flavescens) and zebrafish (Danio rerio) reproduction. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lakes basin, a...

  12. Comparative effects of constant versus fluctuating thermal regimens on yellow perch growth, feed conversion and survival

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of fluctuating or constant thermal regimens on growth, mortality, and feed conversion were determined for juvenile yellow perch (Perca flavescens). Yellow perch averaging 156mm total length and 43g body weight were held in replicate 288L circular tanks for 129 days under: 1) a diel therm...

  13. Identification of gender in yellow perch Perca flavescens using external morphology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A non-lethal and rapid method for reliable identification of gender in yellow perch has been developed. On average, yellow perch females grow faster than males and undergo sexual maturity at an earlier age. Such size discrepancies in mixed culture situations pose difficulties with aquaculture produc...

  14. [Influencing factors in measuring absorption coefficient of suspended particulate matters].

    PubMed

    Yu, Xiao-long; Shen, Fang; Zhang, Jin-fang

    2013-05-01

    Absorption coefficient of suspended particulate matters in natural water is one of the key parameters in ocean color remote sensing. In order to study the influencing factors that affect the measurement, a series of experiments were designed to measure samples using transmittance method (T method), transmittance-reflectance method (T-R method) and absorptance method (A method). The results shows that absorption coefficient measured by the A method has a much lower error compared to the T method and T-R method due to influencing factors,such as filter-to-filter variations, water content of the filter, and homogeneity of filter load and so on. Another factor influence absorption coefficient is path-length amplification induced by multiple scattering inside the filter. To determine the path-length amplification, the true absorption was measured by AC-s (WetLabs). The linear fitting result shows that the mean path-length amplification is much higher for the A method than that of the T-R method and the T method (4.01 versus 2.20 and 2.32), and the corresponding correlation coefficient are 0.90, 0.87 and 0.80. For the A method and the T-R method, higher correlation coefficients are calculated when using polynomial fitting, and the value are 0.95 and 0.94. Analysis of the mean relative error caused by different influencing factors indicates that path-length amplification is the largest error source in measuring the absorption coefficient.

  15. The effect of perch availability during pullet rearing and egg laying on the behavior of caged White Leghorn hens.

    PubMed

    Hester, P Y; Garner, J P; Enneking, S A; Cheng, H W; Einstein, M E

    2014-10-01

    Enriched cages, compared with conventional cages, allow egg laying strains of chickens to meet some behavioral needs, including a high motivation to perch. The objective of this study was to determine if perch availability during rearing affected perch use as adults and if perch presence affected eating and drinking in caged White Leghorn hens. Chickens were assigned to 14 cages each with and without 2 round metal perches from hatch to 16.9 wk of age. At 17 wk of age, pullets were assigned to laying cages consisting of 1 of 4 treatments. Treatment 1 chickens never had access to perches (controls). Treatment 2 chickens only had access to 2 round metal perches during the laying phase (17 to 71 wk of age). Treatment 3 chickens only had access to 2 round perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had access to the perches during both the pullet and laying phase. Each treatment during the adult phase consisted of 9 cages with 9 birds/cage for a total of 36 cages. Automatic infrared cameras were used to monitor behavior of hens in each cage for a 24-h period at 19, 24, 29, 34, 39, 44, 49, 54, 59, 64, and 69 wk of age. Behavior was also recorded twice weekly by an observer in the room where the hens were housed during photophase from 25 to 68 wk of age. Behavioral data were analyzed using ANOVA with repeated measures and the MIXED model procedure. A greater proportion of hens without perches as pullets used the rear perch more during both photophase and scotophase than hens with prior pullet perching experience. Eating and drinking activities of caged adult Leghorns were not impaired by their prior experience to perches as pullets or by the presence of perches in laying cages. It is concluded that providing perches in cages to White Leghorns during pullet rearing did not facilitate use of perches as adults. PMID:25125558

  16. The effect of perch availability during pullet rearing and egg laying on the behavior of caged White Leghorn hens.

    PubMed

    Hester, P Y; Garner, J P; Enneking, S A; Cheng, H W; Einstein, M E

    2014-10-01

    Enriched cages, compared with conventional cages, allow egg laying strains of chickens to meet some behavioral needs, including a high motivation to perch. The objective of this study was to determine if perch availability during rearing affected perch use as adults and if perch presence affected eating and drinking in caged White Leghorn hens. Chickens were assigned to 14 cages each with and without 2 round metal perches from hatch to 16.9 wk of age. At 17 wk of age, pullets were assigned to laying cages consisting of 1 of 4 treatments. Treatment 1 chickens never had access to perches (controls). Treatment 2 chickens only had access to 2 round metal perches during the laying phase (17 to 71 wk of age). Treatment 3 chickens only had access to 2 round perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had access to the perches during both the pullet and laying phase. Each treatment during the adult phase consisted of 9 cages with 9 birds/cage for a total of 36 cages. Automatic infrared cameras were used to monitor behavior of hens in each cage for a 24-h period at 19, 24, 29, 34, 39, 44, 49, 54, 59, 64, and 69 wk of age. Behavior was also recorded twice weekly by an observer in the room where the hens were housed during photophase from 25 to 68 wk of age. Behavioral data were analyzed using ANOVA with repeated measures and the MIXED model procedure. A greater proportion of hens without perches as pullets used the rear perch more during both photophase and scotophase than hens with prior pullet perching experience. Eating and drinking activities of caged adult Leghorns were not impaired by their prior experience to perches as pullets or by the presence of perches in laying cages. It is concluded that providing perches in cages to White Leghorns during pullet rearing did not facilitate use of perches as adults.

  17. Research on Factors Influencing Individual's Behavior of Energy Management

    NASA Astrophysics Data System (ADS)

    Fan, Yanfeng

    With the rapid rise of distributed generation, Internet of Things, and mobile Internet, both U.S. and European smart home manufacturers have developed energy management solutions for individual usage. These applications help people manage their energy consumption more efficiently. Domestic manufacturers have also launched similar products. This paper focuses on the factors influencing Energy Management Behaviour (EMB) at the individual level. By reviewing academic literature, conducting surveys in Beijing, Shanghai and Guangzhou, the author builds an integrated behavioural energy management model of the Chinese energy consumers. This paper takes the vague term of EMB and redefines it as a function of two separate behavioural concepts: Energy Management Intention (EMI), and the traditional Energy Saving Intention (ESI). Secondly, the author conducts statistical analyses on these two behavioural concepts. EMI is the main driver behind an individual's EMB. EMI is affected by Behavioural Attitudes, Subjective Norms, and Perceived Behavioural Control (PBC). Among these three key factors, PBC exerts the strongest influence. This implies that the promotion of the energy management concept is mainly driven by good application user experience (UX). The traditional ESI also demonstrates positive influence on EMB, but its impact is weaker than the impacts arising under EMI's three factors. In other words, the government and manufacturers may not be able to change an individual's energy management behaviour if they rely solely on their traditional promotion strategies. In addition, the study finds that the government may achieve better promotional results by launching subsidies to the manufacturers of these kinds of applications and smart appliances.

  18. Factors influencing the publishing efforts of graduate students in nursing.

    PubMed

    Whitley, G G; Oddi, L F; Terrell, D

    1998-04-01

    The purposes of this study were to identify factors influencing publication efforts of graduate students in nursing and determine the extent to which graduate students' scholarly activities contribute to the creation and dissemination of knowledge in nursing, as evidenced by publication in a professional journal. Authors of articles in Nursing Research were surveyed to assess their status as graduate students during the conceptualization, development, and publication of nursing research studies. The sample consisted of 633 authors of manuscripts published in Nursing Research from 1987 to 1991. The study design was descriptive. A survey questionnaire elicited data on graduate student status and factors that influenced the initiation and completion of the project. The data were analyzed using descriptive statistical techniques. The results of the study suggest that graduate students in nursing make important contributions to the advancement and dissemination of nursing knowledge. Factors that influence graduate students to engage in the process include academic requirements (e.g., thesis, dissertation, coursework), faculty involvement and support, and the ability to self-select the research topic.

  19. 75 FR 69599 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch by Vessels in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Economic Zone Off Alaska; Pacific Ocean Perch by Vessels in the Amendment 80 Limited Access Fishery in the...: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by vessels... ocean perch total allowable catch specified for vessels participating in the Amendment 80 limited...

  20. 77 FR 41332 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-13

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Regulatory Area of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting retention of Pacific ocean perch in the... allowable catch (TAC) of Pacific ocean perch in the Western Regulatory Area of the GOA has been...

  1. 75 FR 69599 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch by Vessels in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Economic Zone Off Alaska; Pacific Ocean Perch by Vessels in the Amendment 80 Limited Access Fishery in the...: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by vessels.... The 2010 Pacific ocean perch TAC specified for vessels participating in the Amendment 80...

  2. 76 FR 54716 - Fisheries of the Exclusive Economic Zone off Alaska; Northern Rockfish, Pacific Ocean Perch, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Economic Zone off Alaska; Northern Rockfish, Pacific Ocean Perch, and Pelagic Shelf Rockfish for Vessels... prohibiting directed fishing for northern rockfish, Pacific ocean perch, and pelagic shelf rockfish for... northern rockfish, Pacific ocean perch, and pelagic shelf rockfish allocated to vessels participating...

  3. 75 FR 42338 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Regulatory Area of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting retention of Pacific ocean perch in the... allowable catch (TAC) of Pacific ocean perch in the Western Regulatory Area of the GOA has been...

  4. 76 FR 43933 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Aleutian District of the Bering Sea and... directed fishing for Pacific ocean perch in the Western Aleutian District of the Bering Sea and Aleutian... action is necessary to prevent exceeding the 2011 allocation of Pacific ocean perch in this...

  5. 77 FR 39649 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-05

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Regulatory Area of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch in... the 2012 total allowable catch (TAC) of Pacific ocean perch in the Western Regulatory Area of the...

  6. 76 FR 40838 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-12

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels Participating in the Rockfish Entry Level...; modification of a closure. SUMMARY: NMFS is opening directed fishing for Pacific ocean perch by trawl catcher... Pacific ocean perch for trawl catcher vessels participating in the rockfish entry level fishery in...

  7. 78 FR 44465 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-24

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat District of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch in... the 2013 total allowable catch (TAC) of Pacific ocean perch in the West Yakutat District of the...

  8. 76 FR 39791 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Regulatory Area of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch in... the 2011 total allowable catch (TAC) of Pacific ocean perch in the Western Regulatory Area of the...

  9. 75 FR 69601 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Aleutian District of the Bering Sea and... directed fishing for Pacific ocean perch in the Western Aleutian District of the Bering Sea and Aleutian... action is necessary to prevent exceeding the 2010 allocation of Pacific ocean perch in this...

  10. 76 FR 45709 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-01

    ... Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat District of the... for Pacific ocean perch in the West Yakutat District of the Gulf of Alaska (GOA). This action is necessary to prevent exceeding the 2011 total allowable catch (TAC) of Pacific ocean perch in the...

  11. 76 FR 46207 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-02

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels Participating in the Rockfish Entry Level...; modification of a closure. SUMMARY: NMFS is opening directed fishing for Pacific ocean perch by trawl catcher... Pacific ocean perch for trawl catcher vessels participating in the rockfish entry level fishery in...

  12. 75 FR 69598 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch by Vessels in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Economic Zone Off Alaska; Pacific Ocean Perch by Vessels in the Amendment 80 Limited Access Fishery in the...: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by vessels.... The 2010 Pacific ocean perch TAC specified for vessels participating in the Amendment 80...

  13. 75 FR 39183 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-08

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Regulatory Area of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch in... the 2010 total allowable catch (TAC) of Pacific ocean perch in the Western Regulatory Area of the...

  14. 75 FR 69601 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Central Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Central Aleutian District of the Bering Sea and... directed fishing for Pacific ocean perch in the Central Aleutian District of the Bering Sea and Aleutian... action is necessary to prevent exceeding the 2010 allocation of Pacific ocean perch in this...

  15. 76 FR 39792 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch, Northern Rockfish, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... Economic Zone Off Alaska; Pacific Ocean Perch, Northern Rockfish, and Pelagic Shelf Rockfish in the Western...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch, northern rockfish, and... exceeding the ] 2011 sideboard limits of Pacific ocean perch, northern rockfish, and pelagic shelf...

  16. 75 FR 43090 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Western Yakutat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Western Yakutat District of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by... appear at subpart H of 50 CFR part 600 and 50 CFR part 679. The 2010 Pacific ocean perch sideboard...

  17. 76 FR 68658 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea Subarea of the Bering Sea and Aleutian... is opening directed fishing for Pacific ocean perch in the Bering Sea subarea of the Bering Sea and... Pacific ocean perch specified for the Bering Sea subarea of the Bering Sea and Aleutian Islands...

  18. 77 FR 42439 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-19

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat District of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch in... the 2012 total allowable catch (TAC) of Pacific ocean perch in the West Yakutat District of the...

  19. 75 FR 53608 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the West Yakutat District of the Gulf of Alaska AGENCY.... ACTION: Temporary rule; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch in... the 2010 total allowable catch (TAC) of Pacific ocean perch in the West Yakutat District of the...

  20. 75 FR 69600 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Eastern Aleutian...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-15

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Eastern Aleutian District of the Bering Sea and... directed fishing for Pacific ocean perch in the Eastern Aleutian District of the Bering Sea and Aleutian... action is necessary to prevent exceeding the 2010 allocation of Pacific ocean perch in this...

  1. Genetic Factors Influence Serological Measures of Common Infections

    PubMed Central

    Rubicz, Rohina; Leach, Charles T.; Kraig, Ellen; Dhurandhar, Nikhil V.; Duggirala, Ravindranath; Blangero, John; Yolken, Robert; Göring, Harald H.H.

    2011-01-01

    Background/Aims Antibodies against infectious pathogens provide information on past or present exposure to infectious agents. While host genetic factors are known to affect the immune response, the influence of genetic factors on antibody levels to common infectious agents is largely unknown. Here we test whether antibody levels for 13 common infections are significantly heritable. Methods IgG antibodies to Chlamydophila pneumoniae, Helicobacter pylori, Toxoplasma gondii, adenovirus 36 (Ad36), hepatitis A virus, influenza A and B, cytomegalovirus, Epstein-Barr virus, herpes simplex virus (HSV)-1 and −2, human herpesvirus-6, and varicella zoster virus were determined for 1,227 Mexican Americans. Both quantitative and dichotomous (seropositive/seronegative) traits were analyzed. Influences of genetic and shared environmental factors were estimated using variance components pedigree analysis, and sharing of underlying genetic factors among traits was investigated using bivariate analyses. Results Serological phenotypes were significantly heritable for most pathogens (h2 = 0.17–0.39), except for Ad36 and HSV-2. Shared environment was significant for several pathogens (c2 = 0.10–0.32). The underlying genetic etiology appears to be largely different for most pathogens. Conclusions Our results demonstrate, for the first time for many of these pathogens, that individual genetic differences of the human host contribute substantially to antibody levels to many common infectious agents, providing impetus for the identification of underlying genetic variants, which may be of clinical importance. PMID:21996708

  2. Factors influencing perceived sustainability of Dutch community health programs.

    PubMed

    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'.

  3. Factors influencing Malaysian public attitudes to agro-biotechnology.

    PubMed

    Amin, Latifah; Ahmad, Jamil; Jahi, Jamaluddin Md; Nor, Abd Rahim Md; Osman, Mohamad; Mahadi, Nor Muhammad

    2011-09-01

    Despite considerable research in advanced countries on public perceptions of and attitudes to modern biotechnology, limited effort has been geared towards developing a structural model of public attitudes to modern biotechnology. The purpose of this paper is to identify the relevant factors influencing public attitudes towards genetically modified (GM) soybean, and to analyze the relationship between all the attitudinal factors. A survey was carried out on 1,017 respondents from various stakeholder groups in the Klang Valley region. Results of the survey have confirmed that attitudes towards complex issues such as biotechnology should be seen as a multifaceted process. The most important factors predicting support for GM soybean are the specific application-linked perceptions about the benefits, acceptance of risk and moral concern while risk and familiarity are significant predictors of benefit and risk acceptance. Attitudes towards GM soybean are also predicted by several general classes of attitude. PMID:22164706

  4. [Factors influencing self-perception of overweight people].

    PubMed

    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. PMID:24575656

  5. Pharmacokinetic, Pharmacogenetic, and Other Factors Influencing CNS Penetration of Antiretrovirals

    PubMed Central

    Babalola, Chinedum Peace; Morse, Gene D.; Taiwo, Babafemi

    2016-01-01

    Neurological complications associated with the human immunodeficiency virus (HIV) are a matter of great concern. While antiretroviral (ARV) drugs are the cornerstone of HIV treatment and typically produce neurological benefit, some ARV drugs have limited CNS penetration while others have been associated with neurotoxicity. CNS penetration is a function of several factors including sieving role of blood-brain and blood-CSF barriers and activity of innate drug transporters. Other factors are related to pharmacokinetics and pharmacogenetics of the specific ARV agent or mediated by drug interactions, local inflammation, and blood flow. In this review, we provide an overview of the various factors influencing CNS penetration of ARV drugs with an emphasis on those commonly used in sub-Saharan Africa. We also summarize some key associations between ARV drug penetration, CNS efficacy, and neurotoxicity. PMID:27777797

  6. Adolescent risk behaviours and protective factors against peer influence.

    PubMed

    Cattelino, Elena; Glowacz, Fabienne; Born, Michel; Testa, Silvia; Bina, Manuela; Calandri, Emanuela

    2014-12-01

    This study examined the relationships between protective factors and involvement in risk behaviour of Italian adolescents with friends involved in risk. Protective factors were drawn from models of peers and from individual skills (perceived regulatory self-efficacy, intolerant attitudes about deviance) and orientation (to health, school, religion). The data are from two waves, 1 year apart, of a questionnaire survey of adolescents in northwestern Italy. Participants were 908 adolescents (42% boys) ages 14-16 years. Results of a hierarchical regression revealed that religiosity is a protective factor and that friends' models for conventional behaviours and positive attitude about health can mitigate the influence of deviant friends on adolescent risk behaviour 1 year later, even after controlling for prior levels of risk behaviour. Possible implications of this study suggest the importance of implementing preventive interventions by involving the peer group, especially at about 16 years, and working with heterogeneous (deviant and nondeviant) groups. PMID:25448830

  7. Factors influencing Malaysian public attitudes to agro-biotechnology.

    PubMed

    Amin, Latifah; Ahmad, Jamil; Jahi, Jamaluddin Md; Nor, Abd Rahim Md; Osman, Mohamad; Mahadi, Nor Muhammad

    2011-09-01

    Despite considerable research in advanced countries on public perceptions of and attitudes to modern biotechnology, limited effort has been geared towards developing a structural model of public attitudes to modern biotechnology. The purpose of this paper is to identify the relevant factors influencing public attitudes towards genetically modified (GM) soybean, and to analyze the relationship between all the attitudinal factors. A survey was carried out on 1,017 respondents from various stakeholder groups in the Klang Valley region. Results of the survey have confirmed that attitudes towards complex issues such as biotechnology should be seen as a multifaceted process. The most important factors predicting support for GM soybean are the specific application-linked perceptions about the benefits, acceptance of risk and moral concern while risk and familiarity are significant predictors of benefit and risk acceptance. Attitudes towards GM soybean are also predicted by several general classes of attitude.

  8. Influence factors affecting career choice of preclinical medical technology students.

    PubMed

    Gleich, C

    1978-06-01

    Over a seven-year period, data were gathered on 249 declared medical technology majors enrolled in an Introduction to Medical Technology course at the University of Iowa. The Kendall Tau C test for significance (p = less than .05) was utilized in determining the influence of several variables or factors in the students' choice of medical technology as a career. Such factors as the type of work, demand for medical technologists, and desire to help people were found to be highly motivating factors in choice. It appeared the motivation was primarily internalized with assistance sought from various sources. The decision of medical technology as a career was predominantly made in the junior/senior year in high school or freshman/sophomore year in college. PMID:686027

  9. Factors Influencing Learning Environments in an Integrated Experiential Program

    NASA Astrophysics Data System (ADS)

    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

  10. Factors influencing scores on the Social Responsiveness Scale

    PubMed Central

    Hus, Vanessa; Bishop, Somer; Gotham, Katherine; Huerta, Marisela; Lord, Catherine

    2012-01-01

    Background The Social Responsiveness Scale (SRS) is a parent-completed screening questionnaire often used to measure ASD severity. Although child characteristics are known to influence scores from other ASD-symptom measures, as well as parent-questionnaires more broadly, there has been limited consideration of how non-ASD-specific factors may affect interpretation of SRS scores. Previous studies have explored effects of behavior problems on SRS specificity, but have not addressed influences on the use of the SRS as a quantitative measure of ASD-symptoms. Method Raw scores (SRS-Raw) from parent-completed SRS were analyzed for 2,368 probands with ASD and 1,913 unaffected siblings. Regression analyses were used to assess associations between SRS scores and demographic, language, cognitive, and behavior measures. Results For probands, higher SRS-Raw were associated with greater non-ASD behavior problems, higher age, and more impaired language and cognitive skills, as well as scores from other parent report measures of social development and ASD-symptoms. For unaffected siblings, having more behavior problems predicted higher SRS-Raw; male gender, younger age and poorer adaptive social and expressive communication skills also showed small, but significant effects. Conclusions When using the SRS as a quantitative phenotype measure, the influence of behavior problems, age, and expressive language or cognitive level on scores must be considered. If effects of non-ASD-specific factors are not addressed, SRS scores are more appropriately interpreted as indicating general levels of impairment, than as severity of ASD-specific symptoms or social impairment. Further research is needed to consider how these factors influence the SRS’ sensitivity and specificity in large, clinical samples including individuals with disorders other than ASD. PMID:22823182

  11. Factors influencing smokeless tobacco use in rural Ohio Appalachia.

    PubMed

    Nemeth, Julianna M; Liu, Sherry T; Klein, Elizabeth G; Ferketich, Amy K; Kwan, Mei-Po; Wewers, Mary Ellen

    2012-12-01

    The burden of smokeless tobacco (ST) use disproportionally impacts males in rural Ohio Appalachia. The purpose of this study was to describe the cultural factors contributing to this disparity and to articulate the way in which culture, through interpersonal factors (i.e. social norms and social networks) and community factors (i.e. marketing and availability), impacts ST initiation and use of ST among boys and men in Ohio Appalachia. Fifteen focus groups and 23 individual qualitative interviews were conducted with adult (n = 63) and adolescent (n = 53) residents in Ohio Appalachian counties to ascertain factors associated with ST use and the impact of ST marketing. Transcriptions were independently coded according to questions and themes. ST use appears to be a rite of passage in the development of masculine identity in Ohio Appalachian culture. Interpersonal factors had the greatest influence on initiation and continued use of ST. Ohio Appalachian boys either emulated current ST users or were actively encouraged to use ST through male family and peer networks. Users perceived their acceptance into the male social network as predicated on ST use. Community factors, including ST advertisement and access to ST, reinforced and normalized underlying cultural values. In addition to policy aimed at reducing tobacco marketing and access, interventions designed to reduce ST use in Ohio Appalachia should incorporate efforts to (1) shift the perception of cultural norms regarding ST use and (2) address male social networks as vehicles in ST initiation.

  12. Factors Influencing Smokeless Tobacco Use in Rural Ohio Appalachia

    PubMed Central

    Nemeth, Julianna M.; Liu, Sherry T.; Klein, Elizabeth G.; Ferketich, Amy K.; Kwan, Mei-Po; Wewers, Mary Ellen

    2015-01-01

    Background The burden of smokeless tobacco (ST) use disproportionally impacts males in rural Ohio Appalachia. The purpose of this study was to describe the cultural factors contributing to this disparity and to articulate the way in which culture, through interpersonal factors (i.e. social norms and social networks) and community factors (i.e. marketing and availability), impacts ST initiation and use of ST among boys and men in Ohio Appalachia. Methods Fifteen focus groups and twenty-three individual qualitative interviews were conducted with adult (n=63) and adolescent (n=53) residents in Ohio Appalachian counties to ascertain factors associated with ST use and the impact of ST marketing. Transcriptions were independently coded according to questions and themes. Results ST use appears to be a rite of passage in the development of masculine identity in Ohio Appalachian culture. Interpersonal factors had the greatest influence on initiation and continued use of ST. Ohio Appalachian boys either emulated current ST users or were actively encouraged to use ST through male family and peer networks. Users perceived their acceptance into the male social network as predicated on ST use. Community factors, including ST advertisement and access to ST, reinforced and normalized underlying cultural values. Conclusions In addition to policy aimed at reducing tobacco marketing and access, interventions designed to reduce ST use in Ohio Appalachia should incorporate efforts to 1) shift the perception of cultural norms regarding ST use and 2) address male social networks as vehicles in ST initiation. PMID:22427033

  13. Factors influencing smokeless tobacco use in rural Ohio Appalachia.

    PubMed

    Nemeth, Julianna M; Liu, Sherry T; Klein, Elizabeth G; Ferketich, Amy K; Kwan, Mei-Po; Wewers, Mary Ellen

    2012-12-01

    The burden of smokeless tobacco (ST) use disproportionally impacts males in rural Ohio Appalachia. The purpose of this study was to describe the cultural factors contributing to this disparity and to articulate the way in which culture, through interpersonal factors (i.e. social norms and social networks) and community factors (i.e. marketing and availability), impacts ST initiation and use of ST among boys and men in Ohio Appalachia. Fifteen focus groups and 23 individual qualitative interviews were conducted with adult (n = 63) and adolescent (n = 53) residents in Ohio Appalachian counties to ascertain factors associated with ST use and the impact of ST marketing. Transcriptions were independently coded according to questions and themes. ST use appears to be a rite of passage in the development of masculine identity in Ohio Appalachian culture. Interpersonal factors had the greatest influence on initiation and continued use of ST. Ohio Appalachian boys either emulated current ST users or were actively encouraged to use ST through male family and peer networks. Users perceived their acceptance into the male social network as predicated on ST use. Community factors, including ST advertisement and access to ST, reinforced and normalized underlying cultural values. In addition to policy aimed at reducing tobacco marketing and access, interventions designed to reduce ST use in Ohio Appalachia should incorporate efforts to (1) shift the perception of cultural norms regarding ST use and (2) address male social networks as vehicles in ST initiation. PMID:22427033

  14. Monitoring athletes through self-report: factors influencing implementation.

    PubMed

    Saw, Anna E; Main, Luana C; Gastin, Paul B

    2015-03-01

    Monitoring athletic preparation facilitates the evaluation and adjustment of practices to optimize performance outcomes. Self-report measures such as questionnaires and diaries are suggested to be a simple and cost-effective approach to monitoring an athlete's response to training, however their efficacy is dependent on how they are implemented and used. This study sought to identify the perceived factors influencing the implementation of athlete self-report measures (ASRM) in elite sport settings. Semi-structured interviews were conducted with athletes, coaches and sports science and medicine staff at a national sporting institute (n = 30). Interviewees represented 20 different sports programs and had varying experience with ASRM. Purported factors influencing the implementation of ASRM related to the measure itself (e.g., accessibility, timing of completion), and the social environment (e.g., buy-in, reinforcement). Social environmental factors included individual, inter-personal and organizational levels which is consistent with a social ecological framework. An adaptation of this framework was combined with the factors associated with the measure to illustrate the inter-relations and influence upon compliance, data accuracy and athletic outcomes. To improve implementation of ASRM and ultimately athletic outcomes, a multi-factorial and multi-level approach is needed. Key pointsEffective implementation of a self-report measure for monitoring athletes requires a multi-factorial and multi-level approach which addresses the particular measure used and the surrounding social environment.A well-designed self-report measure should obtain quality data with minimal burden on athletes and staff.A supportive social environment involves buy-in and coordination of all parties, at both an individual and organization level.

  15. Monitoring Athletes Through Self-Report: Factors Influencing Implementation

    PubMed Central

    Saw, Anna E.; Main, Luana C.; Gastin, Paul B.

    2015-01-01

    Monitoring athletic preparation facilitates the evaluation and adjustment of practices to optimize performance outcomes. Self-report measures such as questionnaires and diaries are suggested to be a simple and cost-effective approach to monitoring an athlete’s response to training, however their efficacy is dependent on how they are implemented and used. This study sought to identify the perceived factors influencing the implementation of athlete self-report measures (ASRM) in elite sport settings. Semi-structured interviews were conducted with athletes, coaches and sports science and medicine staff at a national sporting institute (n = 30). Interviewees represented 20 different sports programs and had varying experience with ASRM. Purported factors influencing the implementation of ASRM related to the measure itself (e.g., accessibility, timing of completion), and the social environment (e.g., buy-in, reinforcement). Social environmental factors included individual, inter-personal and organizational levels which is consistent with a social ecological framework. An adaptation of this framework was combined with the factors associated with the measure to illustrate the inter-relations and influence upon compliance, data accuracy and athletic outcomes. To improve implementation of ASRM and ultimately athletic outcomes, a multi-factorial and multi-level approach is needed. Key points Effective implementation of a self-report measure for monitoring athletes requires a multi-factorial and multi-level approach which addresses the particular measure used and the surrounding social environment. A well-designed self-report measure should obtain quality data with minimal burden on athletes and staff. A supportive social environment involves buy-in and coordination of all parties, at both an individual and organization level. PMID:25729301

  16. Factors influencing behavior in the forced swim test.

    PubMed

    Bogdanova, Olena V; Kanekar, Shami; D'Anci, Kristen E; Renshaw, Perry F

    2013-06-13

    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.

  17. Factors influencing physicians' knowledge sharing on web medical forums.

    PubMed

    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. PMID:25888432

  18. [Factors influencing psychotherapeutic treatment outcome of various syndromes].

    PubMed

    Hartmann, Sebastian; Zepf, Siegfried

    2004-12-01

    The authors investigated specific and unspecific factors influencing the psychotherapeutic treatment of various syndromes using a questionnaire which systematically replicated the Consumer Reports Study performed in the USA in 1994. The authors were particularly concerned with the degree to which certain psychotherapeutic methods - psychoanalysis, depth psychology-based psychotherapy and behavioral therapy - produced differing results following treatment of syndromes. Using cluster-analysis, two groups of syndromes could be distinguished: Patients with depressive symptoms, stress-related disorders and/or relationship problems (depression-group) and patients with anxiety disorders and/or eating-related disorders (anxiety-group). With the help of cart-analysis (Classification and Regression Trees) it was possible to identify factors influencing the improvement of symptoms. The method of treatment had not a specific effect on the improvement of symptoms. In both groups the most important predictor was the length of treatment. Furthermore in the depression group the sex of the patients and a possible restriction of the treatment by the health insurance companies influenced the treatment results and in the anxiety group the frequency of treatment and the age of the patients. PMID:15551189

  19. High Enrollment Course Success Factors in Virtual School: Factors Influencing Student Academic Achievement

    ERIC Educational Resources Information Center

    Liu, Feng; Cavanaugh, Cathy

    2011-01-01

    This paper describes a study of success factors in high enrollment courses in a K-12 virtual school learning environment. The influence of variables: time student spent in the learning management system (LMS), number of times logged into the LMS, teacher comment, participation in free or reduced lunch programs, student status in the virtual school…

  20. Influencing factors of transient elastography in detecting liver stiffness

    PubMed Central

    Shan, Rong; Yin, Hong; Yang, Wenjuan; Li, Jianzhi; Zhang, Meifang; Zhao, Min; Shao, Jiang; Wang, Aiguang

    2016-01-01

    Liver stiffness, which correlates well with liver fibrosis stage, can be measured noninvasively by transient elastography, also known as Fibroscan. The present study aimed to determine the independent factors influencing Fibroscan detection by multiple regression analysis. A total of 181 patients who required liver biopsy were enrolled. Liver stiffness measurement (LSM) was detected by Fibroscan on the day of liver biopsy, while clinical information and routine biochemical examination results were also collected. Correlation was analyzed by Spearman's correlation, and multiple regression analysis was performed to analyze the independent influencing factors. The results demonstrated that platelet (PLT) levels, serum albumin (ALB), prothrombin activity (PTA) and body mass index (BMI) were independent predictors of liver stiffness. The contribution of these four predictors to the regression equation was in the following descending order: PLT (negative correlation) > ALB (negative correlation) > PTA (negative correlation) > BMI (positive correlation). In conclusion, the parameters of PLT, ALB, PTA and BMI are independent predicting factors affecting Fibroscan detection. Therefore, the diagnosis and evaluation of liver fibrosis should comprehensively consider the results of Fibroscan, and clinical and laboratory examinations.

  1. A Broad Set of Chromatin Factors Influences Splicing

    PubMed Central

    Allemand, Eric; Myers, Michael P.; Garcia-Bernardo, Jose; Harel-Bellan, Annick; Krainer, Adrian R.; Muchardt, Christian

    2016-01-01

    Several studies propose an influence of chromatin on pre-mRNA splicing, but it is still unclear how widespread and how direct this phenomenon is. We find here that when assembled in vivo, the U2 snRNP co-purifies with a subset of chromatin-proteins, including histones and remodeling complexes like SWI/SNF. Yet, an unbiased RNAi screen revealed that the outcome of splicing is influenced by a much larger variety of chromatin factors not all associating with the spliceosome. The availability of this broad range of chromatin factors impacting splicing further unveiled their very context specific effect, resulting in either inclusion or skipping, depending on the exon under scrutiny. Finally, a direct assessment of the impact of chromatin on splicing using an in vitro co-transcriptional splicing assay with pre-mRNAs transcribed from a nucleosomal template, demonstrated that chromatin impacts nascent pre-mRNP in their competence for splicing. Altogether, our data show that numerous chromatin factors associated or not with the spliceosome can affect the outcome of splicing, possibly as a function of the local chromatin environment that by default interferes with the efficiency of splicing. PMID:27662573

  2. Influencing factors of mental health of medical students in China.

    PubMed

    Yang, Fan; Meng, Heng; Chen, Hui; Xu, Xin-hao; Liu, Zhuo; Luo, Ai; Feng, Zhan-chun

    2014-06-01

    This study investigated the mental health status of medical students in China, and analyzed the influencing factors in order to provide evidence for mental health education for medical students. A stratified cluster sampling method was used to recruit medical students from Huazhong University of Science and Technology, China. The questionnaire survey on general information and Symptom Checklist 90 (SCL-90) were used for investigation and analysis. The results showed among the 1137 valid questionnaires, 278 (24.45%) participants had SCL-90 score ≥ 160. The top three mental problems of medical students were obsessive-compulsive disorder, interpersonal sensitivity and depression in terms of the factor score ≥ 2.5 and the number of participants who reflected on the diseases. The third-year medical students had the worst mental health status, and fifth-year medical students had the best mental health status. Students from rural area had more psychological problems than those from urban area; furthermore, students with high professional satisfaction, those who were the single child of the family, non-poor students, and those whose parents had high education level had better mental health status. It was concluded that the mental health of medical students is not optimistic in China. Medical students have some mental health problems of different degrees. Factors that influence the mental health of medical students include academic pressure, professional satisfaction level and family environment.

  3. Expecting success: Factors influencing ninth graders' science self-efficacy

    NASA Astrophysics Data System (ADS)

    Donahue, Elizabeth

    What factors influence ninth grade students' expectations for success in science? Using social cognitive theory and bioecological systems theory as theoretical frameworks, this dissertation employs data from the High School Longitudinal Study of 2009 (HSLS:09) to examine the relative impact of teacher practices and their perceived attitudes on students' science self-efficacy. Further, as they relate to this broader issue, the relative impact of student subjective task value and teacher characteristics is also investigated. It has been well documented that U.S. students are not achieving at satisfactory levels in science. Education policy has focused on improving science teacher quality as one way to address this problem. Teacher effectiveness has been primarily measured by student achievement on standardized tests. However, not enough attention has been given to the social cognitive factors that can lead to increased achievement and persistence in science as well as how teachers may influence these factors. This study interrogates the relationship between student and teacher variables and the social cognitive construct of self-efficacy, which has proven to have a significant impact on student achievement and persistence in science. Findings add to the current literature surrounding ways that educators may increase student performance in science by employing policies and practices that benefit the development of student science self-efficacy.

  4. Factors influencing quality of bowel preparation for colonoscopy.

    PubMed

    Romero, Ronald V; Mahadeva, Sanjiv

    2013-02-16

    Recent technological advances in colonoscopy have led to improvements in both image enhancement and procedural performance. However, the utility of these technological advancements remain dependent on the quality of bowel preparation during colonoscopy. Poor bowel preparation has been shown to be associated with lower quality indicators of colonoscopy performance, such as reduced cecal intubation rates, increased patient discomfort and lower adenoma detection. The most popular bowel preparation regimes currently used are based on either Polyethylene glycol-electrolyte, a non-absorbable solution, or aqueous sodium phosphate, a low-volume hyperosmotic solution. Statements from various international societies and several reviews have suggested that the efficacy of bowel preparation regimes based on both purgatives are similar, although patients' compliance with these regimes may differ somewhat. Many studies have now shown that factors other than the type of bowel preparation regime used, can influence the quality of bowel preparation among adult patients undergoing colonoscopy. These factors can be broadly categorized as either patient-related or procedure-related. Studies from both Asia and the West have identified patient-related factors such as an increased age, male gender, presence of co-morbidity and socio-economic status of patients to be associated with poor bowel preparation among adults undergoing routine out-patient colonoscopy. Additionally, procedure-related factors such as adherence to bowel preparation instructions, timing of bowel purgative administration and appointment waiting times for colonoscopy are recognized to influence the quality of colon cleansing. Knowledge of these factors should aid clinicians in modifying bowel preparation regimes accordingly, such that the quality of colonoscopy performance and delivery of service to patients can be optimised.

  5. Factors Influencing the Management of Unruptured Intracranial Aneurysms.

    PubMed

    Gillani, Rebecca L; Podraza, Katherine M; Luthra, Nijee; Origitano, Thomas C; Schneck, Michael J

    2016-01-01

    Background Deciding how to manage an unruptured intracranial aneurysm can be difficult for patients and physicians due to controversies about management. The decision as to when and how to intervene may be variable depending on physicians' interpretation of available data regarding natural history and morbidity and mortality of interventions. Another significant factor in the decision process is the patients' conception of the risks of rupture and interventions and the psychological burden of harboring an unruptured intracranial aneurysm. Objective  To describe which factors are being considered when patients and their physicians decide how to manage unruptured intracranial aneurysms.  Materials & methods  In a retrospective chart review study, we identified patients seen for evaluation of an unruptured intracranial aneurysm. Data was collected regarding patient and aneurysm characteristics. The physician note pertaining to the management decision was reviewed for documented reasons for intervention. Results  Of 88 patients included, 36 (41%) decided to undergo open or endovascular surgery for at least one unruptured intracranial aneurysm. Multiple aneurysms were present in 14 (16%) patients. Younger patients and current smokers were more likely to undergo surgery, but gender and race did not affect management. Aneurysm size and location strongly influenced management. The most common documented reasons underlying the decision of whether to intervene were the risk of rupture, aneurysm size, and risks of the procedure. For 23 aneurysms (21%), there were no factors documented for the management decision.  Conclusion  The risk of rupture of unruptured intracranial aneurysms may be underestimated by currently available natural history data. Major factors weighed by physicians in management decisions include aneurysm size and location, the patient's age, and medical comorbidities along with the risk of procedural complications. Additional data is needed to define

  6. Training community health workers: factors that influence mammography use.

    PubMed

    Kratzke, Cynthia; Garzon, Laurel; Lombard, John; Karlowicz, Karen

    2010-12-01

    The purpose of this study was to assess factors that influence mammography use among volunteer community health workers (CHWs). Data trends indicate lower mammography rates among minority and low-income women. Although CHW interventions have been shown to promote mammography use among this population, training strategies and the use of a comprehensive needs assessment are lacking. Using a cross-sectional study design, data were collected via a mailed survey. The dependent variable was mammography use within the past 2 years. The independent variables were categorized according to the factors in the PRECEDE-PROCEED model. Predisposing factors included susceptibility, barriers, benefits, health motivation, self-efficacy, education, and age. Enabling factors included income, health insurance, and regular source of care. Reinforcing factors included physician recommendation to get a mammogram, social norms, and family history of breast cancer. Self-reported data from a mailed survey were obtained from a convenience sample of urban CHWS (N = 109) ages 40-73 with a mean age of 55 (SD = 9.43). The sample included 90% African American and 8% White women. Logistic regression results showed barriers to be predictive of mammography use among CHWs controlling for age, self-efficacy, health motivation, and social norms. The findings suggest CHW training focus on how to identify and address barriers to increase the likelihood of mammography use among CHWs. Future research is needed to identify cultural differences in barriers for minority CHWs.

  7. Factors influencing reductions in smoking among Australian adolescents.

    PubMed

    Dessaix, Anita; Maag, Audrey; McKenzie, Jeanie; Currow, David C

    2016-01-01

    A continued increase in the proportion of adolescents who never smoke, as well as an understanding of factors that influence reductions in smoking among this susceptible population, is crucial. The World Health Organization Framework Convention on Tobacco Control provides an appropriate structure to briefly examine Australian and New South Wales policies and programs that are influencing reductions in smoking among adolescents in Australia. This paper provides an overview of price and recent tax measures to reduce the demand for tobacco, the evolution of smoke-free environment policies, changes to tobacco labelling and packaging, public education campaigns, and restrictions to curb tobacco advertising. It also discusses supplyreduction measures that limit adolescents' access to tobacco products. Consideration is given to emerging priorities to achieve continued declines in smoking by Australian adolescents. PMID:26863168

  8. Factors influencing stakeholders attitudes toward genetically modified aedes mosquito.

    PubMed

    Amin, Latifah; Hashim, Hasrizul

    2015-06-01

    Dengue fever is a debilitating and infectious disease that could be life-threatening. It is caused by the dengue virus which affects millions of people in the tropical area. Currently, there is no cure for the disease as there is no vaccine available. Thus, prevention of the vector population using conventional methods is by far the main strategy but has been found ineffective. A genetically modified (GM) mosquito is among the favoured alternatives to curb dengue fever in Malaysia. Past studies have shown that development and diffusion of gene technology products depends heavily upon public acceptance. The purpose of this study is to identify the relevant factors influencing stakeholders' attitudes toward the GM Aedes mosquito and to analyse the relationships between all the factors using the structural equation model. A survey was carried out on 509 respondents from various stakeholder groups in the Klang Valley region of Malaysia. Results of the survey have confirmed that public perception towards complex issues such as gene technology should be seen as a multi-faceted process. The perceived benefit-perceived risk balance is very important in determining the most predominant predictor of attitudes toward a GM mosquito. In this study the stakeholders perceived the benefit of the GM mosquito as outweighing its risk, translating perceived benefit as the most important direct predictor of attitudes toward the GM mosquito. Trust in key players has a direct influence on attitudes toward the GM mosquito while moral concern exhibited an indirect influence through perceived benefits. Other factors such as attitudes toward technology and nature were also indirect predictors of attitudes toward the GM mosquito while religiosity and engagement did not exhibited any significant roles. The research findings serve as a useful database to understand public acceptance and the social construct of public attitudes towards the GM mosquito to combat dengue. PMID:24906652

  9. Factors influencing outcome of pregnancy in heavy-drinking women.

    PubMed

    Qazi, Q H; Chua, A; Milman, D; Solish, G

    1982-01-01

    18 pregnant women identified as heavy drinkers by the criteria of Cahalan et al., gave birth to 6 normal infants, 5 infants with fetal alcohol syndrome (FAS) and 7 with partial FAS. Average daily alcohol consumption of mothers of normal infants was less than that of mothers of FAS and partial FAS infants. Lower socioeconomic class, higher parity and increased use of tobacco and other drugs were non-alcohol-related maternal factors which appeared to influence the outcome of pregnancy in heavy-drinking women.

  10. Manual flying skills under the influence of performance shaping factors.

    PubMed

    Haslbeck, Andreas; Schubert, Ekkehart; Onnasch, Linda; Hüttig, Gerhard; Bubb, Heiner; Bengler, Klaus

    2012-01-01

    This paper describes an experimental study investigating pilots' manual flying skills. In today's line oriented flight training, basic flying skills are neglected frequently. So, the study examines the manual flying skills of commercial airline pilots under the influence of several performance shaping factors like training, practice or fatigue in a landing scenario. The landing phase shows a disproportionate high percentage of aircraft accidents and it is typically flown by hand. The study is to be undertaken with randomly selected pilots in a full motion flight simulator to ensure a high validity of the results. PMID:22316719

  11. Factors influencing trace element composition in human teeth

    SciTech Connect

    Tandon, L.; Iyengar, G.V.

    1997-12-01

    The authors recently compiled and reviewed the literature published in or after 1978 for 45 major, minor, and trace elements in human teeth as a part of an International Atomic Energy Agency (IAEA) study. The purpose of this paper is to discuss the various factors that influence the concentration levels of certain trace elements in human teeth. The sampling practices and analytical techniques that are applicable for trace element analysis are also discussed. It is also our intention to identify reference range of values, where data permit such conclusions. The scrutiny was designed to identify only the healthy permanent teeth, and values from teeth with fillings, caries, or periodontal diseases were eliminated.

  12. Changes in yellow perch (Perca flavescens) populations of Lake Michigan, 1954-75

    USGS Publications Warehouse

    Wells, LaRue

    1977-01-01

    In the early and mid-1960s the abundance of yellow perch (Perca flavescens) in Lake Michigan declined abruptly. The decline began in the northern part of the lake and spread progressively southward. Circumstantial evidence suggests that the nonnative alewife (Alosa pseudoharengus), by interfering with perch reproduction, was the primary cause of the decline. The alewife was first reported in northeastern Lake Michigan in 1949, and had become extremely abundant throughout the lake before an enormous die-off in 1967 reduced its numbers by an estimated 70%. An intensive fishery hastened the decline of perch. In most areas the decline was immediately preceded by a period of conspicuously high commercial production. This high production appears to have been related in part to increased growth rates of perch resulting from much lower density of younger fish. A sport fishery for perch in shallow water collapsed a few years before the species declined in abundance. The most logical explanation is that heavy concentrations of alewives physically displaced the perch from nearshore areas. Although perch populations increased in some areas in the 1970s, a full recovery is unlikely unless alewife numbers are further reduced.

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

    USGS Publications Warehouse

    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.

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

    USGS Publications Warehouse

    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. Factors Influencing Dating Experiences Among African American Emerging Adults

    PubMed Central

    Hall, Naomi M.; Lee, Anna K.; Witherspoon, Daphne D.

    2014-01-01

    This study examined sociocultural factors that impact dating and sexual experiences of heterosexual African American undergraduate college students attending a historically Black institution in the Southeastern United States. Specifically, mate availability and relationship involvement were analyzed to document students’ experiences, and how these influences may be associated with sexual decision making and behavior. Data from nine focus groups (N = 57) were aggregated and four subthemes were identified: competition among women, acceptability of mates, high prevalence of casual relationships, and lowered expectations for commitment. Power dynamics emerged as a contributing factor to the types of relationship involvement, sexual decision-making, and behavior among participants. The importance of prevention programs focusing on situational and cultural variables is highlighted. Additionally, implications for professionals working with emerging adults to consider the impact of the gender ratio imbalance, and perceived power distributions on perceptions of dating relationships, and sexual decision making and behavior are addressed. PMID:25530924

  16. The effect of perch access during pullet rearing and egg laying on physiological measurements of stress in 71-week-old White Leghorns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Egg laying strains of chickens have a strong motivation to perch. Providing caged chickens with perches allows them to perform their natural perching instinct and also improves their musculoskeletal health due to exercise. Little is known about the effect of perch access by hens on physiological mea...

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

    PubMed

    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

  18. Lake phosphorus loading form septic systems by seasonally perched groundwater

    USGS Publications Warehouse

    Gilliom, R.J.; Patmont, C.R.

    1983-01-01

    The movement of effluent phosphorus (P) from old septic systems by seasonally perched groundwater was investigated. A previous study indicated a correlation between P loadings and the presence of old homes. Water samples were taken from shallow wells installed 10 to 50 m downgradient from seven septic systems 20 to 40 years old. The equivalent volumetric fraction of each sample consisting of undiluted effluent was estimated from chloride concentration. A Monte Carlo analysis was used to account for the various sources of uncertainty. Movement of diluted septic effluent to the lake was common, but transport of more than 1% of effluent P through the soil was probable for only 4 of 26 samples. The greatest apparent P movement was associated with persistently saturated conditions.

  19. A robin perches on a branch at KSC

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A robin perches on a branch in the Merritt Island National Wildlife Refuge, which shares a boundary with the space center. Robins range throughout North America, from Alaska to Florida. Although considered a harbinger of spring, they do winter in northern states, frequenting cedar bogs and swamps. They also winter in Florida, where they often can be seen in flocks of hundreds near KSC and the wildlife refuge, which comprises 92,000 acres, ranging from hardwood hammocks and pine flatwoods to fresh-water impoundments, salt-water estuaries and brackish marshes. The diverse landscape provides habitat for more than 310 species of birds, 25 mammals, 117 fishes, and 65 amphibians and reptiles, including such endangered species as Southern bald eagles, wood storks, Florida scrub jays, Atlantic loggerhead and leatherback turtles, osprey, and nearly 5,000 alligators.

  20. A mockingbird perches on a limb at KSC

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A mockingbird perches on a limb in the Merritt Island National Wildlife Refuge at Kennedy Space Center. The birds range from southern Canada south to the Caribbean and winter in the southern part of the range. Mockingbirds are very vocal, often imitating the sounds of other birds. Besides providing a winter home for the mockingbird, the refuge provides wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds. The 92,000- acre refuge is also habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles.

  1. Factors That Influence the Extensional Rheological Property of Saliva.

    PubMed

    Vijay, Amrita; Inui, Taichi; Dodds, Michael; Proctor, Gordon; Carpenter, Guy

    2015-01-01

    The spinnbarkeit of saliva reflects the ability of saliva to adhere to surfaces within the mouth, thereby serving as a protective role and aiding in lubrication. Therefore, alterations in the extensional rheology of saliva may result in the loss in adhesiveness or the ability to bind onto surfaces. Mucin glycoproteins and their structures are known to be important factors for the extensional rheological properties of saliva. The conformation of mucin depends on factors such as pH and ionic strength. Chewing is one of the main stimuli for salivary secretion but creates significant sheer stress on the salivary film which could influence mouthfeel perceptions. The current study investigates the possible factors which affect the extensional rheological properties of saliva by comparing submandibular/sublingual saliva with different oral stimuli within the same group of subjects. Unstimulated and stimulated saliva (chew, smell and taste) salivas were collected primarily from submandibular/sublingual glands. The saliva samples were measured for Spinnbarkeit followed by the measuring mucin, total protein, total calcium and bicarbonate concentrations. The results indicated correlations between rheological properties and mucin/ion concentrations. However, chewing stimulated submandibular/sublingual saliva is shown to have significantly lower Spinnbarkeit, but factors such as mucin, protein and calcium concentrations did not account for this variation. Analysis of the concentration of bicarbonate and pH appears to suggest that it has a prominent effect on extensional rheology of saliva. PMID:26305698

  2. Factors That Influence the Extensional Rheological Property of Saliva

    PubMed Central

    Vijay, Amrita; Inui, Taichi; Dodds, Michael; Proctor, Gordon; Carpenter, Guy

    2015-01-01

    The spinnbarkeit of saliva reflects the ability of saliva to adhere to surfaces within the mouth, thereby serving as a protective role and aiding in lubrication. Therefore, alterations in the extensional rheology of saliva may result in the loss in adhesiveness or the ability to bind onto surfaces. Mucin glycoproteins and their structures are known to be important factors for the extensional rheological properties of saliva. The conformation of mucin depends on factors such as pH and ionic strength. Chewing is one of the main stimuli for salivary secretion but creates significant sheer stress on the salivary film which could influence mouthfeel perceptions. The current study investigates the possible factors which affect the extensional rheological properties of saliva by comparing submandibular/sublingual saliva with different oral stimuli within the same group of subjects. Unstimulated and stimulated saliva (chew, smell and taste) salivas were collected primarily from submandibular/sublingual glands. The saliva samples were measured for Spinnbarkeit followed by the measuring mucin, total protein, total calcium and bicarbonate concentrations. The results indicated correlations between rheological properties and mucin/ion concentrations. However, chewing stimulated submandibular/sublingual saliva is shown to have significantly lower Spinnbarkeit, but factors such as mucin, protein and calcium concentrations did not account for this variation. Analysis of the concentration of bicarbonate and pH appears to suggest that it has a prominent effect on extensional rheology of saliva. PMID:26305698

  3. Factors That Influence the Extensional Rheological Property of Saliva.

    PubMed

    Vijay, Amrita; Inui, Taichi; Dodds, Michael; Proctor, Gordon; Carpenter, Guy

    2015-01-01

    The spinnbarkeit of saliva reflects the ability of saliva to adhere to surfaces within the mouth, thereby serving as a protective role and aiding in lubrication. Therefore, alterations in the extensional rheology of saliva may result in the loss in adhesiveness or the ability to bind onto surfaces. Mucin glycoproteins and their structures are known to be important factors for the extensional rheological properties of saliva. The conformation of mucin depends on factors such as pH and ionic strength. Chewing is one of the main stimuli for salivary secretion but creates significant sheer stress on the salivary film which could influence mouthfeel perceptions. The current study investigates the possible factors which affect the extensional rheological properties of saliva by comparing submandibular/sublingual saliva with different oral stimuli within the same group of subjects. Unstimulated and stimulated saliva (chew, smell and taste) salivas were collected primarily from submandibular/sublingual glands. The saliva samples were measured for Spinnbarkeit followed by the measuring mucin, total protein, total calcium and bicarbonate concentrations. The results indicated correlations between rheological properties and mucin/ion concentrations. However, chewing stimulated submandibular/sublingual saliva is shown to have significantly lower Spinnbarkeit, but factors such as mucin, protein and calcium concentrations did not account for this variation. Analysis of the concentration of bicarbonate and pH appears to suggest that it has a prominent effect on extensional rheology of saliva.

  4. Influencing factors of hydrogen bonding intensity in beer.

    PubMed

    Liu, Chunfeng; Dong, Jianjun; Yin, Xiangsheng; Li, Qi; Gu, Guoxian

    2014-11-01

    The hydrogen bonding was prone to be formed by many components in beer. Different sorts of flavor substances can affect the Chemical Shift due to their different concentrations in beer. Several key factors including 4 alcohols, 2 esters, 6 ions, 9 acids, 7 polyphenols, and 2 gravity indexes (OG and RG) were determined in this research. They could be used to investigate the relationship between hydrogen bonding intensity and the flavor components in bottled larger beers through the Correlation Analysis, Principal Component Analysis and Multiple Regression Analysis. Results showed that ethanol content was the primary influencing factor, and its correlation coefficient was 0.629 for Correlation Analysis. Some factors had a positive correlation with hydrogen bonding intensity, including the content of original gravity, ethanol, isobutanol, Cl(-), K(+), pyruvic acid, lactic acid, gallic acid, vanillic acid, and Catechin in beer. A mathematic model of hydrogen bonding Chemical Shift and the content of ethanol, pyruvic acid, K(+), and gallic acid was obtained through the Principal Component Analysis and Multiple Regression Analysis , with the adjusted R(2) being 0.779 (P = 0.001). Ethanol content was proved to be the most important factor which could impact on hydrogen bonding association in beer by Principal Component Analysis. And then, a multiple non-linearity model could be obtained as follows: [Formula: see text]. The average error was 1.23 % in the validated experiment. PMID:26396290

  5. Factors influencing inclusion of patients with malignancies in clinical trials.

    PubMed

    Tournoux, Caroline; Katsahian, Sandrine; Chevret, Sylvie; Levy, Vincent

    2006-01-15

    Participation in clinical trials remains low and is a central issue in oncology. The authors identified, through a systematic review, 75 papers published up to August 2004 that report barriers to recruitment of patients in clinical trials. These barriers range from patient preference and concern about information/consent to clinical problems with protocols. Strategies to overcome barriers on the part of patients and clinicians are needed and should be carefully evaluated. Thirty-three (44%) papers reported factors related to patients as influencing the inclusion of patients, 28 (37%) reported clinician's related factors, and 37 (49%) other factors from either specific groups of patients (30 papers, 40%) and/or other scopes (13 papers, 17%). No differences in prevalence were found between papers dedicated to hematologic malignancies and solid tumors. Factors related to clinicians as influential were more frequently reported before 1995 (70%) than thereafter (25%; P = 0.0009). Reporting specific groups of patients as influential was more frequent in North American articles (50%) than in others (14%, P = 0.008). Patients' barriers included mostly patient preference (12 papers), concern about information and/or consent (11 papers), worry about uncertainty (7 papers), and/or relationship with medical team (7 papers). Concerning clinicians, incompatibility of protocol with normal practice (nine papers), problems in complying with the protocol (eight papers), and/or consent procedure (eight papers) were the most reported factors. The remaining factors mostly relied on specific groups of patients (30 papers), notably age of patients (18 papers) and/or minority population (11 papers, all from the USA). Strategies to overcome these barriers are needed and should be carefully evaluated. PMID:16397866

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

    PubMed

    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

    2015-01-01

    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. PMID:25625518

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

    PubMed Central

    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.

    2015-01-01

    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. PMID:25625518

  8. Biology, Genetics, and Environment: Underlying Factors Influencing Alcohol Metabolism.

    PubMed

    Wall, Tamara L; Luczak, Susan E; Hiller-Sturmhöfel, Susanne

    2016-01-01

    Gene variants encoding several of the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), are among the largest genetic associations with risk for alcohol dependence. Certain genetic variants (i.e., alleles)--particularly the ADH1B*2, ADH1B*3, ADH1C*1, and ALDH2*2 alleles--have been associated with lower rates of alcohol dependence. These alleles may lead to an accumulation of acetaldehyde during alcohol metabolism, which can result in heightened subjective and objective effects. The prevalence of these alleles differs among ethnic groups; ADH1B*2 is found frequently in northeast Asians and occasionally Caucasians, ADH1B*3 is found predominantly in people of African ancestry, ADH1C*1 varies substantially across populations, and ALDH2*2 is found almost exclusively in northeast Asians. Differences in the prevalence of these alleles may account at least in part for ethnic differences in alcohol consumption and alcohol use disorder (AUD). However, these alleles do not act in isolation to influence the risk of AUD. For example, the gene effects of ALDH2*2 and ADH1B*2 seem to interact. Moreover, other factors have been found to influence the extent to which these alleles affect a person's alcohol involvement, including developmental stage, individual characteristics (e.g., ethnicity, antisocial behavior, and behavioral undercontrol), and environmental factors (e.g., culture, religion, family environment, and childhood adversity).

  9. Factors Influencing the Dysmenorrhea among Korean Adolescents in Middle School.

    PubMed

    Jeon, Ga Eul; Cha, Nam Hyun; Sok, Sohyune R

    2014-09-01

    [Purpose] This study aimed to examine the factors influencing dysmenorrhea among Korean middle school adolescents. [Subjects] The subjects included 572 female students in three different middle schools located in Seoul, South Korea. [Methods] A cross-sectional design was adopted. The measurement tools used included a demographic form and revised Menstrual distress Questionnaire (MDQ). [Results] The analyses showed that the prediction model was significant. The value of the adjusted R(2) was 0.282, which corresponds to an explanatory power of 28.2%. The factor found to have the most influence on dysmenorrhea among Korean middle school adolescents was stress, followed by health status, onset of dysmenorrhea, consecutive days of menstruation, and dietary habits. [Conclusion] Nursing intervention programs for alleviating dysmenorrhea in Korean middle school adolescents are essential in order to reduce their level of stress, improve their perceived health status, and help them to maintain regular dietary habits. Reflecting on the recent trend of female students menstruating at a younger age, public health education courses and counseling programs should offer customized methods for alleviating dysmenorrhea.

  10. A holistic model of advocacy: factors that influence its use.

    PubMed

    Kubsch, Sylvia M; Sternard, Marsha J; Hovarter, Rebecca; Matzke, Vicki

    2004-02-01

    Although advocacy is embraced by nursing as an essential component of holistic philosophy, its scope is often limited in practice. In this article, a research study that examined the use of an expanded definition of advocacy is described. A link to the role of advocacy as a complementary therapy and in relation to facilitating the use of complementary therapies by patients is provided. Fifty-two registered nurses completed a researcher developed advocacy research instrument that assessed the use of moral-ethical, legal, political, spiritual, and substitutive advocacy along with various factors thought to influence the use of advocacy including moral development, perceived assertiveness, and perceived job security. An additional 40 RN-BSN students generated case studies of advocacy enacted in practice that were used as examples of the five categories of advocacy and to support the findings of the survey. Results indicated that moral-ethical advocacy was used more often than the other four categories. Moral stage development had a significant effect on substitutive advocacy but assertiveness and job security were not significant factors influencing any category of advocacy. PMID:14744505

  11. Equilibrium and kinetic factors influencing bile sequestrant efficacy.

    PubMed

    Luner, P E; Amidon, G L

    1992-05-01

    In vitro bile salt binding equilibria and kinetic studies were performed with cholestyramine to determine how these factors influence bile sequestrant efficacy in vivo. Chloride ion at physiologic concentrations caused more than a twofold reduction in glycocholate (GCH) binding, compared to binding in the absence of salt, over a range of GCH concentrations and was also observed to displace bound GCH. In addition, chloride ion displaced from cholestyramine as a result of bile salt binding was measured using a chloride selective electrode, and the results show that bile salt binding is due to ion exchange. Comparison of the results of the equilibrium binding experiments to human data shows that the effect of anion binding competition alone cannot account for the lack of efficacy of cholestyramine. Consideration of other effects, such as additional binding competition or poor availability for binding, based on data from the literature, shows that adequate bile salt binding potential exists and that these interferences are not major factors influencing resin efficacy. In kinetic studies, both binding uptake of GCH and displacement of GCH from cholestyramine by chloride ion were relatively rapid, indicating that cholestyramine should equilibrate rapidly with bile salts in the GI tract. Based on these findings, it is suggested that the low efficacy of cholestyramine is a result mainly of its relatively poor ability to prevent bile salt reabsorption in the ileum.

  12. In-hospital resuscitation: opioids and other factors influencing survival

    PubMed Central

    Fecho, Karamarie; Jackson, Freeman; Smith, Frances; Overdyk, Frank J

    2009-01-01

    Purpose: “Code Blue” is a standard term used to alertt hospital staff that a patient requires resuscitation. This study determined rates of survival from Code Blue events and the role of opioids and other factors on survival. Methods: Data derived from medical records and the Code Blue and Pharmacy databases were analyzed for factors affecting survival. Results: During 2006, rates of survival from the code only and to discharge were 25.9% and 26.4%, respectively, for Code Blue events involving cardiopulmonary resuscitation (CPR; N = 216). Survival rates for events not ultimately requiring CPR (N = 77) were higher, with 32.5% surviving the code only and 62.3% surviving to discharge. For CPR events, rates of survival to discharge correlated inversely with time to chest compressions and defibrillation, precipitating event, need for airway management, location and age. Time of week, witnessing, postoperative status, gender and opioid use did not influence survival rates. For non-CPR events, opioid use was associated with decreased survival. Survival rates were lowest for patients receiving continuous infusions (P < 0.01) or iv boluses of opioids (P < 0.05). Conclusions: One-quarter of patients survive to discharge after a CPR Code Blue event and two-thirds survive to discharge after a non-CPR event. Opioids may influence survival from non-CPR events. PMID:20057895

  13. Identification of the influencing factors on groundwater drought in Bangladesh

    NASA Astrophysics Data System (ADS)

    Touhidul Mustafa, Syed Md.; Huysmans, Marijke

    2015-04-01

    Groundwater drought is a specific type of drought that concerns groundwater bodies. It may have a significant adverse effect on the socio-economic, agricultural, and environmental conditions. Investigating the effect of response different climatic and manmade factors on groundwater drought provides essential information for sustainable planning and management of water resources. The aim of this study is to identify the influencing factors on groundwater drought in a drought prone region in Bangladesh to understand the forcing mechanisms. The Standardised Precipitation Index (SPI) and Reconnaissance Drought Index (RDI) have been used to quantify the aggregated deficit between precipitation and the evaporative demand of the atmosphere. The influence of land use patterns on the groundwater drought has been identified by calculating spatially distributed groundwater recharge as a function of land use. The result shows that drought intensity is more severe during the dry season (November to April) compared to the rainy season (May to October). The evapotranspiration and rainfall deficit has a significant effect on meteorological drought which has a direct relation with groundwater drought. Urbanization results in a decrease of groundwater recharge which increases groundwater drought severity. Overexploitation of groundwater for irrigation and recurrent meteorological droughts are the main causes of groundwater drought in the study area. Efficient irrigation management is essential to reduce the growing pressure on groundwater resources and ensure sustainable water management. More detailed studies on climate change and land use change effects on groundwater drought are recommended. Keywords: Groundwater drought, SPI & RDI, Spatially distributed groundwater recharge, Irrigation, Bangladesh

  14. A holistic model of advocacy: factors that influence its use.

    PubMed

    Kubsch, Sylvia M; Sternard, Marsha J; Hovarter, Rebecca; Matzke, Vicki

    2004-02-01

    Although advocacy is embraced by nursing as an essential component of holistic philosophy, its scope is often limited in practice. In this article, a research study that examined the use of an expanded definition of advocacy is described. A link to the role of advocacy as a complementary therapy and in relation to facilitating the use of complementary therapies by patients is provided. Fifty-two registered nurses completed a researcher developed advocacy research instrument that assessed the use of moral-ethical, legal, political, spiritual, and substitutive advocacy along with various factors thought to influence the use of advocacy including moral development, perceived assertiveness, and perceived job security. An additional 40 RN-BSN students generated case studies of advocacy enacted in practice that were used as examples of the five categories of advocacy and to support the findings of the survey. Results indicated that moral-ethical advocacy was used more often than the other four categories. Moral stage development had a significant effect on substitutive advocacy but assertiveness and job security were not significant factors influencing any category of advocacy.

  15. Biology, Genetics, and Environment: Underlying Factors Influencing Alcohol Metabolism.

    PubMed

    Wall, Tamara L; Luczak, Susan E; Hiller-Sturmhöfel, Susanne

    2016-01-01

    Gene variants encoding several of the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), are among the largest genetic associations with risk for alcohol dependence. Certain genetic variants (i.e., alleles)--particularly the ADH1B*2, ADH1B*3, ADH1C*1, and ALDH2*2 alleles--have been associated with lower rates of alcohol dependence. These alleles may lead to an accumulation of acetaldehyde during alcohol metabolism, which can result in heightened subjective and objective effects. The prevalence of these alleles differs among ethnic groups; ADH1B*2 is found frequently in northeast Asians and occasionally Caucasians, ADH1B*3 is found predominantly in people of African ancestry, ADH1C*1 varies substantially across populations, and ALDH2*2 is found almost exclusively in northeast Asians. Differences in the prevalence of these alleles may account at least in part for ethnic differences in alcohol consumption and alcohol use disorder (AUD). However, these alleles do not act in isolation to influence the risk of AUD. For example, the gene effects of ALDH2*2 and ADH1B*2 seem to interact. Moreover, other factors have been found to influence the extent to which these alleles affect a person's alcohol involvement, including developmental stage, individual characteristics (e.g., ethnicity, antisocial behavior, and behavioral undercontrol), and environmental factors (e.g., culture, religion, family environment, and childhood adversity). PMID:27163368

  16. Reproductive health of yellow perch, Perca flavescens, in Chesapeake Bay Tributaries

    USGS Publications Warehouse

    Blazer, Vicki; Pinkney, A.E.; Uphoff, James H.

    2013-01-01

    Yellow perch live in creeks, rivers, ponds, lakes, and estuaries across the central and eastern United States and Canada. In Chesapeake Bay, they tolerate salinities up to one-third that of seawater. The adults reside in the brackish waters of the bay’s tributaries and migrate upstream to spawn. Yellow perch are eagerly sought by recreational fishermen for their excellent taste and, because their late winter spawning runs are the earliest of the year, they are regarded as a harbinger of spring. Yellow perch also support a small but valuable, tightly regulated commercial fishery in the part of Chesapeake Bay that lies in Maryland.

  17. Environmental Factors Influencing Arctic Halogen Chemistry During Late Spring

    NASA Astrophysics Data System (ADS)

    Burd, J.; Nghiem, S. V.; Simpson, W. R.

    2015-12-01

    Reactive halogen radicals (e.g. Br, Cl atoms and their oxides, BrO, ClO) are important oxidizers in the troposphere that decrease atmospheric pollutants and deplete tropospheric ozone, affecting the abundance of other oxidizers such as the hydroxyl radical. During Arctic springtime, the heterogeneous chemical cycles (often called the "bromine explosion") produce high levels of bromine monoxide (BrO), through reactions on saline snow, ice, and/or aerosol surfaces. Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) measured BrO at Barrow, AK, from 2008-2009 and 2012-2015, as well at various locations above the frozen Arctic Ocean with O-Buoys in 2008 and 2011-2015. Observed BrO levels drop suddenly during late spring (May-June) and generally do not recover, which indicates the bromine explosion cycle can no longer produce significant amounts of BrO. We have established, through an objective algorithm, the local day of year of this drop in BrO as the "seasonal end." Additionally, in about half of the years, "recurrence" events were observed where BrO levels recover for at least a day. This study investigates the environmental factors influencing seasonal end and recurrence events including: temperature, relative humidity, precipitation and snowmelt. Analysis of BrO and air temperature revealed the temperature reaches 0°C within five days of the seasonal end event; however, temperatures drop below freezing during a recurrence event. In addition, there are periods where the temperature remains below freezing, but no recurrence event is observed. This BrO and temperature analysis indicates above-freezing air temperature prevents reactive bromine release; however, it is not the only environmental factor influencing this heterogeneous recycling. Further analysis of additional environmental influences on the bromine explosion cycle could help to better understand and model bromine chemistry in the Arctic.

  18. Some factors that influence semen characteristics in rabbits.

    PubMed

    Theau-Clément, M; Bolet, G; Sanchez, A; Saleil, G; Brun, J M

    2015-06-01

    The aim of this study, based on a five-year-long experiment, was to analyse some of the factors that influence rabbit sperm production. A total of 174 bucks between 23 and 44 weeks of age from five successive groups were used for semen collection one day per week, two times, at a 15 min interval (ejaculates of rank 1 and 2), over a period of 21 weeks. Immediately after collection, pH, mass motility, volume and concentration were measured using classical methods, and a set of motility parameters were recorded by a computer-assisted semen analysis system. Between groups, the number of motile sperm per ejaculate, considered as a synthetic criterion combining both qualitative and quantitative aspects of semen characteristics, varied from simple to double (from 150 to 326×10(6)), reflecting the strong influence of uncontrolled environmental factors. Adult (37-43 weeks old) expressed a higher number of motile sperm/ejaculate than younger bucks (300 vs. 205×10(6)). In autumn the number of motile sperm/ejaculate was higher than in summer (287 vs. 188×10(6)). Sperm production was higher on average for the first ejaculate compared to the second one (270 vs. 167×10(6)). For several semen characteristics, the effect of the collector was significant but without any repercussion on sperm production. Bucks born to nulliparous or primiparous does had higher performances. This study highlights the high variability of rabbit semen characteristics and the multitude of factors involved, either controlled or uncontrolled. PMID:25862381

  19. Influencing factors for dietary behaviors of patients with diabetic nephropathy.

    PubMed

    Sumiyoshi, Kazuko; Kawata, Chieko; Shikata, Kenichi; Makino, Hirofumi

    2010-02-01

    The aim of this study was to clarify the factors influencing the dietary behavior of patients with diabetic nephropathy. One hundred twenty-two patients with type 2 diabetes were recruited from the outpatients of Okayama University Hospital in Okayama, Japan. We performed a cross-sectional study using a questionnaire including 206 items among 18 categories as follows: background factors, coping behavior (coping scale), degree of uncertainty in illness (uncertainty scale), and dietary behavior. The data were analyzed by correlation analysis, t-test, one-way analysis of variance, Pearson correlation analysis, and multiple regression analysis. We found that those patients with microalbuminuria alone tended to recognize more mild about their kidney status than those with macroalbuminuria and chronic renal failure. We also found that common factors influencing the dietary behavior of diabetic patients with and without nephropathy are as follows: 1. coping with the problem (beta = 0.342, p < 0.01); 2. anxiety about prognosis (beta = -0.344, p < 0.01); 3. sex (beta = -0.234, p < 0.05); 4. uncertainty regarding treatment (beta = 0.377, p < 0.01); 5. negative coping (beta = -0.354, p< 0.01); and 6. employment status (beta = 0.367, p < 0.01). Coping and uncertainty in illness had a significant relation to positive support and lack of support. To maintain appropriate dietary behavior in diabetic patients, medical staff need to determine what the social supports are important for the patient, and also to ensure good communication among healthcare personnel as well as positive support for patients and families.

  20. Risk Factors Influencing Smoking Behavior: A Turkish Twin Study

    PubMed Central

    Öncel, Sevgi Yurt; Dick, Danielle M.; Maes, Hermine H.; Alıev, Fazil

    2015-01-01

    Aim In this study, we introduce the first twin study in Turkey, focusing on smoking behavior, and laying the foundation to register all twins born in Turkey for research purposes. Using Turkish twins will contribute to our understanding of health problems in the context of cultural differences. Materials and methods We assessed 309 twin pairs (339 males and 279 females) aged between 15 and 45 years living in the Kırıkkale and Ankara regions of Turkey, and administered a health and lifestyle interview that included questions about smoking status and smoking history. We analyzed the data using descriptive statistics, t-tests, chi-square tests, and bivariate and multivariate clustered logistic regression. In addition, we fit bivariate Structural Equation Models (SEM) to determine contributions of latent genetic and environmental factors to smoking outcomes in this sample. Results One hundred seventy-eight participants (28.8%) were identified as smokers, smoking every day for a month or longer, of whom 79.2% were males and 20.8% were females. Mean values for number of cigarettes per day and the Fagerstrom Test of Nicotine Dependence (FTND; Fagerstrom, 1978) score were higher in males than in females, and age of onset was earlier in males. There was a significant positive correlation between the FTND score and number of cigarettes smoked per day, and a significant negative correlation between both variables and age at onset of smoking. Our study showed that gender, presence of a smoking twin in the family, age, alcohol use, marital status, daily sports activities, and feeling moody all played a significant role in smoking behavior among twins. The twin analysis suggested that 79.5% of the liability to FTND was influenced by genetic factors and 20.5% by unique environment, while familial resemblance for smoking initiation was best explained by common environmental factors. Conclusions Marked differences in the prevalence of smoking behavior in men versus women were

  1. Local and regional factors influencing bacterial community assembly.

    PubMed

    Lindström, Eva S; Langenheder, Silke

    2012-02-01

    The classical view states that microbial biogeography is not affected by dispersal barriers or historical events, but only influenced by the local contemporary habitat conditions (species sorting). This has been challenged during recent years by studies suggesting that also regional factors such as mass effect, dispersal limitation and neutral assembly are important for the composition of local bacterial communities. Here we summarize results from biogeography studies in different environments, i.e. in marine, freshwater and soil as well in human hosts. Species sorting appears to be the most important mechanism. However, this result might be biased since this is the mechanism that is easiest to measure, detect and interpret. Hence, the importance of regional factors may have been underestimated. Moreover, our survey indicates that different assembly mechanisms might be important for different parts of the total community, differing, for example, between generalists and specialists, and between taxa of different dispersal ability and motility. We conclude that there is a clear need for experimental studies, first, to clearly separate regional and local factors in order to study their relative importance, and second, to test whether there are differences in assembly mechanisms depending on different taxonomic or functional groups.

  2. Abiotic environmental factors influencing blowfly colonisation patterns in the field.

    PubMed

    George, Kelly A; Archer, Melanie S; Toop, Tes

    2013-06-10

    The accuracy of minimum post-mortem interval (mPMI) estimates usually hinges upon the ability of forensic entomologists to predict the conditions under which calliphorids will colonise bodies. However, there can be delays between death and colonisation due to poorly understood abiotic and biotic factors, hence the need for a mPMI. To quantify the importance of various meteorological and light-level factors, beef liver baits were placed in the field (Victoria, Australia) on 88 randomly selected days over 3 years in all seasons and observed every 60-90 min for evidence of colonisation. Baits were exposed during daylight, and the following parameters were measured: barometric pressure, light intensity, wind speed, ambient temperature, relative humidity and rainfall. Collected data were analysed using backward LR logistic regression to produce an equation of colonisation probability. This type of analysis removes factors with the least influence on colonisation in successive steps until all remaining variables significantly increase the accuracy of predicting colonisation presence or absence. Ambient temperature was a positive predictor variable (an increase in temperature increased the probability of calliphorid colonisation). Relative humidity was a negative predictor variable (an increase in humidity decreased the probability of calliphorid colonisation). Barometric pressure, light intensity, wind speed and rainfall did not enhance the accuracy of the probability model; however, analysis of species activity patterns suggests that heavy rainfall and strong wind speeds inhibit calliphorid colonisation.

  3. Factors that Influence Weekday Sleep Duration in European Children

    PubMed Central

    Hense, Sabrina; Barba, Gianvincenzo; Pohlabeln, Hermann; De Henauw, Stefaan; Marild, Staffan; Molnar, Dénes; Moreno, Luis A.; Hadjigeorgiou, Charalampos; Veidebaum, Toomas; Ahrens, Wolfgang

    2011-01-01

    Study Objectives: To compare nocturnal sleep duration in children from 8 European countries and identify its determinants. Design: Cross-sectional. Setting: Primary schools and preschools participating in the IDEFICS study. Participants: 8,542 children aged 2 to 9 years from 8 European countries with complete information on nocturnal sleep duration. Interventions: Not applicable. Measurements: Nocturnal sleep duration was assessed by means of a computer based parental 24-h recall. Data on personal, social, environmental, and behavioral factors were collected by means of standardized parental questionnaire. Physical activity was surveyed with accelerometers. Results: Nocturnal sleep duration in the participating countries ranged from 9.5 h (SD 0.8) in Estonia to 11.2 h (SD 0.7) in Belgium and differed significantly between countries (P < 0.001) in univariate as well as in multivariate analyses, with children from northern countries sleeping the longest. Sleep duration decreased by about 6 min with each year of age over all countries. No effect of season, daylight duration, overweight, parental education level, or lifestyle factors could be seen. Conclusion: Sleep duration differs significantly between countries. Our findings allow for the conclusion that regional affiliation, including culture and environmental characteristics, seems to overlay individual determinants of sleep duration. Citation: Hense S; Barba G; Pohlabeln H; De Henauw S; Marild S; Molnar D; Moreno LA; Hadjigeorgiou C; Veidebaum T; Ahrens W. Factors that influence weekday sleep duration in European children. SLEEP 2011;34(5):633-639. PMID:21532957

  4. Social and ecological factors influencing offspring survival in wild macaques

    PubMed Central

    Kerhoas, Daphne; Perwitasari-Farajallah, Dyah; Agil, Muhammad; Widdig, Anja

    2014-01-01

    Premature loss of offspring decreases direct fitness of parents. In gregarious mammals, both ecological and social variables impact offspring survival and may interact with each other in this regard. Although a number of studies have investigated factors influencing offspring loss in mammals, we still know very little on how different factors interact with one another. We therefore investigated fetal and infant mortality in 3 large groups of wild crested macaques (Macaca nigra) over a period of up to 5 years by including potential social causes such as maternal dominance rank, male immigration, between group encounters, and ecological conditions such as rainfall in a multivariate survival analysis using Cox proportional hazards model. Infant but not fetal survival was most impaired after a recent takeover of the alpha-male position by an immigrant male. Furthermore, infant survival probability increased when there was an increase in number of group adult females and rainfall. Fetal survival probability also increased with an increase of these 2 factors, but more in high-ranking than low-ranking females. Fetal survival, unlike that of infants, was also improved by an increase of intergroup encounter rates. Our study thus stresses the importance of survival analyses using a multivariate approach and encompassing more than a single offspring stage to investigate the determinants of female direct fitness. We further provide evidence for fitness costs and benefits of group living, possibly deriving from high pressures of both within- and between-group competition, in a wild primate population. PMID:25214754

  5. Factors influencing the stream-aquifer flow exchange coefficient.

    PubMed

    Morel-Seytoux, Hubert J; Mehl, Steffen; Morgado, Kyle

    2014-01-01

    Knowledge of river gain from or loss to a hydraulically connected water table aquifer is crucial in issues of water rights and also when attempting to optimize conjunctive use of surface and ground waters. Typically in groundwater models this exchange flow is related to a difference in head between the river and some point in the aquifer, through a "coefficient." This coefficient has been defined differently as well as the location for the head in the aquifer. This paper proposes a new coefficient, analytically derived, and a specific location for the point where the aquifer head is used in the difference. The dimensionless part of the coefficient is referred to as the SAFE (stream-aquifer flow exchange) dimensionless conductance. The paper investigates the factors that influence the value of this new conductance. Among these factors are (1) the wetted perimeter of the cross-section, (2) the degree of penetration of the cross-section, and (3) the shape of the cross-section. The study shows that these factors just listed are indeed ordered in their respective level of importance. In addition the study verifies that the analytical correct value of the coefficient is matched by finite difference simulation only if the grid system is sufficiently fine. Thus the use of the analytical value of the coefficient is an accurate and efficient alternative to ad hoc estimates for the coefficient typically used in finite difference and finite element methods.

  6. Perceptual factors that influence use of computer enhanced visual displays

    NASA Technical Reports Server (NTRS)

    Littman, David; Boehm-Davis, Debbie

    1993-01-01

    This document is the final report for the NASA/Langley contract entitled 'Perceptual Factors that Influence Use of Computer Enhanced Visual Displays.' The document consists of two parts. The first part contains a discussion of the problem to which the grant was addressed, a brief discussion of work performed under the grant, and several issues suggested for follow-on work. The second part, presented as Appendix I, contains the annual report produced by Dr. Ann Fulop, the Postdoctoral Research Associate who worked on-site in this project. The main focus of this project was to investigate perceptual factors that might affect a pilot's ability to use computer generated information that is projected into the same visual space that contains information about real world objects. For example, computer generated visual information can identify the type of an attacking aircraft, or its likely trajectory. Such computer generated information must not be so bright that it adversely affects a pilot's ability to perceive other potential threats in the same volume of space. Or, perceptual attributes of computer generated and real display components should not contradict each other in ways that lead to problems of accommodation and, thus, distance judgments. The purpose of the research carried out under this contract was to begin to explore the perceptual factors that contribute to effective use of these displays.

  7. Patient risk factors' influence on survival of posterior composites.

    PubMed

    van de Sande, F H; Opdam, N J; Rodolpho, P A Da Rosa; Correa, M B; Demarco, F F; Cenci, M S

    2013-07-01

    This practice-based retrospective study evaluated the survival of resin composite restorations in posterior teeth, focusing on the influence of potential patient risk factors. In total, 306 posterior composite restorations placed in 44 adult patients were investigated after 10 to 18 yrs. The history of each restoration was extracted from the dental records, and a clinical evaluation was performed with those still in situ. The patient risk status was assessed for caries and "occlusal-stress" (bruxism-related). Statistical analysis was performed by the Kaplan-Meier method and Cox-regression multivariate analysis. In total, 30% of the restorations failed, of which 82% were found in patients with 1 or 2 risk factors. Secondary caries was the main reason of failure within caries-risk patients, whereas fracture was the main reason in "occlusal-stress-risk" patients. The patient variables gender and age did not significantly affect survival, but risk did (p < .001). Tooth type (p < .001), arch (p = .013), and pulpal vitality (p = .003) significantly affected restoration survival. Within the limits of this retrospective evaluation, the survival of restorations is affected by patient risk factors, which should be included in survival analyses of restorations.

  8. Factors influencing the stream-aquifer flow exchange coefficient.

    PubMed

    Morel-Seytoux, Hubert J; Mehl, Steffen; Morgado, Kyle

    2014-01-01

    Knowledge of river gain from or loss to a hydraulically connected water table aquifer is crucial in issues of water rights and also when attempting to optimize conjunctive use of surface and ground waters. Typically in groundwater models this exchange flow is related to a difference in head between the river and some point in the aquifer, through a "coefficient." This coefficient has been defined differently as well as the location for the head in the aquifer. This paper proposes a new coefficient, analytically derived, and a specific location for the point where the aquifer head is used in the difference. The dimensionless part of the coefficient is referred to as the SAFE (stream-aquifer flow exchange) dimensionless conductance. The paper investigates the factors that influence the value of this new conductance. Among these factors are (1) the wetted perimeter of the cross-section, (2) the degree of penetration of the cross-section, and (3) the shape of the cross-section. The study shows that these factors just listed are indeed ordered in their respective level of importance. In addition the study verifies that the analytical correct value of the coefficient is matched by finite difference simulation only if the grid system is sufficiently fine. Thus the use of the analytical value of the coefficient is an accurate and efficient alternative to ad hoc estimates for the coefficient typically used in finite difference and finite element methods. PMID:24010703

  9. Factors That Influence Line Managers' Perceptions of Hospital Performance Data

    PubMed Central

    Ginsburg, Liane Soberman

    2003-01-01

    Objective To design and test a model of the factors that influence frontline and midlevel managers' perceptions of usefulness of comparative reports of hospital performance. Study Setting A total of 344 frontline and midlevel managers with responsibility for stroke and medical cardiac patients in 89 acute care hospitals in the Canadian province of Ontario. Study Design Fifty-nine percent of managers responded to a mail survey regarding managers' familiarity with a comparative report of hospital performance, ratings of the report's data quality, relevance and complexity, improvement culture of the organization, and perceptions of usefulness of the report. Extraction Methods Exploratory factor analysis was performed to assess the dimensionality of performance data characteristics and improvement culture. Antecedents of perceived usefulness and the role of improvement culture as a moderator were tested using hierarchical regression analyses. Principal Findings Both data characteristics variables including data quality, relevance, and report complexity, as well as organizational factors including dissemination intensity and improvement culture, explain significant amounts of variance in perceptions of usefulness of comparative reports of hospital performance. The total R2 for the full hierarchical regression model=.691. Improvement culture moderates the relationship between data relevance and perceived usefulness. Conclusions Organizations and those who fund and design performance reports need to recognize that both report characteristics and organizational context play an important role in determining line managers' response to and ability to use these types of data. PMID:12650391

  10. Modifiable factors influencing relapses and disability in multiple sclerosis.

    PubMed

    D'hooghe, M B; Nagels, G; Bissay, V; De Keyser, J

    2010-07-01

    A growing body of literature indicates that the natural course of multiple sclerosis can be influenced by a number of factors. Strong evidence suggests that relapses can be triggered by infections, the postpartum period and stressful life events. Vaccinations against influenza, hepatitis B and tetanus appear to be safe. Surgery, general and epidural anaesthesia, and physical trauma are not associated with an increased risk of relapses. Factors that have been associated with a reduced relapse rate are pregnancy, exclusive breastfeeding, sunlight exposure and higher vitamin D levels. A number of medications, including hormonal fertility treatment, seem to be able to trigger relapses. Factors that may worsen progression of disability include stressful life events, radiotherapy to the head, low levels of physical activity and low vitamin D levels. Strong evidence suggests that smoking promotes disease progression, both clinically and on brain magnetic resonance imaging. There is no evidence for an increased progression of disability following childbirth in women with multiple sclerosis. Moderate alcohol intake and exercise might have a neuroprotective effect, but this needs to be confirmed. PMID:20483884

  11. Proximate and landscape factors influence grassland bird distributions

    USGS Publications Warehouse

    Cunningham, M.A.; Johnson, D.H.

    2006-01-01

    Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conservation concern, in the Sheyenne National Grassland in North Dakota, USA. The Grassland contains a diverse array of grassland and woodland habitats. We surveyed breeding birds on 2015 100 m long transect segments during 2002 and 2003. We modeled the occurrence of 19 species in relation to habitat features (percentages of grassland, woodland, shrubland, and wetland) within each 100-m segment and to tree cover within 200-1600 m of the segment. We used information-theoretic statistical methods to compare models and variables. At the proximate scales, tree cover was the most important variable, having negative influences on 13 species and positive influences on two species. In a comparison of multiple scales, models with only proximate variables were adequate for some species, but models combining proximate with landscape information were best for 17 of 19 species. Landscape-only models were rarely competitive. Combined models at the largest scales (800-1600 m) were best for 12 of 19 species. Seven species had best models including 1600-m landscapes plus proximate factors in at least one year. These were Wilson's Phalarope (Phalaropus tricolor), Sedge Wren (Cistothorus platensis), Field Sparrow (Spizella pusilla), Grasshopper Sparrow (Ammodramus savannarum), Bobolink (Dolychonix oryzivorus), Red-winged Blackbird (Agelaius phoeniceus), and Brown-headed Cowbird (Molothrus ater). These seven are small-bodied species; thus larger-bodied species do not necessarily respond most to the largest landscapes. Our findings suggest that birds respond to habitat features at a variety of

  12. Proximate and landscape factors influence grassland bird distributions.

    PubMed

    Cunningham, Mary Ann; Johnson, Douglas H

    2006-06-01

    Ecologists increasingly recognize that birds can respond to features well beyond their normal areas of activity, but little is known about the relative importance of landscapes and proximate factors or about the scales of landscapes that influence bird distributions. We examined the influences of tree cover at both proximate and landscape scales on grassland birds, a group of birds of high conservation concern, in the Sheyenne National Grassland in North Dakota, USA. The Grassland contains a diverse array of grassland and woodland habitats. We surveyed breeding birds on 2015 100 m long transect segments during 2002 and 2003. We modeled the occurrence of 19 species in relation to habitat features (percentages of grassland, woodland, shrubland, and wetland) within each 100-m segment and to tree cover within 200-1600 m of the segment. We used information-theoretic statistical methods to compare models and variables. At the proximate scales, tree cover was the most important variable, having negative influences on 13 species and positive influences on two species. In a comparison of multiple scales, models with only proximate variables were adequate for some species, but models combining proximate with landscape information were best for 17 of 19 species. Landscape-only models were rarely competitive. Combined models at the largest scales (800-1600 m) were best for 12 of 19 species. Seven species had best models including 1600-m landscapes plus proximate factors in at least one year. These were Wilson's Phalarope (Phalaropus tricolor), Sedge Wren (Cistothorus platensis), Field Sparrow (Spizella pusilla), Grasshopper Sparrow (Ammodramus savannarum), Bobolink (Dolychonix oryzivorus), Red-winged Blackbird (Agelaius phoeniceus), and Brown-headed Cowbird (Molothrus ater). These seven are small-bodied species; thus larger-bodied species do not necessarily respond most to the largest landscapes. Our findings suggest that birds respond to habitat features at a variety of

  13. 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.

    PubMed

    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.

  14. Perch-hunting in insectivorous Rhinolophus bats is related to the high energy costs of manoeuvring in flight.

    PubMed

    Voigt, Christian C; Schuller, B-Markus; Greif, Stefan; Siemers, Björn M

    2010-10-01

    Foraging behaviour of bats is supposedly largely influenced by the high costs of flapping flight. Yet our understanding of flight energetics focuses mostly on continuous horizontal forward flight at intermediate speeds. Many bats, however, perform manoeuvring flights at suboptimal speeds when foraging. For example, members of the genus Rhinolophus hunt insects during short sallying flights from a perch. Such flights include many descents and ascents below minimum power speed and are therefore considered energetically more expensive than flying at intermediate speed. To test this idea, we quantified the energy costs of short manoeuvring flights (<2 min) using the Na-bicarbonate technique in two Rhinolophus species that differ in body mass but have similar wing shapes. First, we hypothesized that, similar to birds, energy costs of short flights should be higher than predicted by an equation derived for bats at intermediate speeds. Second, we predicted that R. mehelyi encounters higher flight costs than R. euryale, because of its higher wing loading. Although wing loading of R. mehelyi was only 20% larger than that of R. euryale, its flight costs (2.61 ± 0.75 W; mean ± 1 SD) exceeded that of R. euryale (1.71 ± 0.37 W) by 50%. Measured flight costs were higher than predicted for R. mehelyi, but not for R. euryale. We conclude that R. mehelyi face elevated energy costs during short manoeuvring flights due to high wing loading and thus may optimize foraging efficiency by energy-conserving perch-hunting.

  15. Familial Influences on Conduct Disorder Reflect 2 Genetic Factors and 1 Shared Environmental Factor

    PubMed Central

    Kendler, Kenneth S.; Aggen, Steven H.; Patrick, Christopher J.

    2013-01-01

    Context Prior studies suggest that antisocial behavior in childhood and adolescence reflects multiple symptomatic dimensions. However, to our knowledge, no prior study has evaluated the underlying nature of the etiologic influences contributing to conduct disorder (CD) symptoms as defined in the DSM. Objective To determine the structure of genetic and environmental risk factors for CD. Design Population-based twin registry. Setting Virginia. Participants Two thousand seven hundred sixty-nine members of male-male twin pairs from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders. Main Outcome Measure Retrospective self-reported symptoms of CD. Results The best-fitting multivariate twin model included 2 genetic factors, 1 shared environmental common factor, and 1 nonshared environmental common factor, along with criterion-specific genetic and nonshared environmental effects. The CD criteria with the strongest loadings on the 2 genetic factors were, respectively, those reflecting rule breaking (eg, playing hooky) and overt aggressive acts (eg, hurting people). The shared environ mental common factor had salient loadings on a distinct set of criteria reflecting covert delinquent acts (eg, stealing and hurting animals). Loadings on the single non-shared environmental common factor were more uniform and less selective. Scores on the 3 familial CD factors were differentially associated with a range of personality, psychopathology, and demographic factors. Conclusions From a genetic perspective, the DSM criteria for CD do not reflect a single dimension of liability. The familial risk to CD is composed of 2 discrete dimensions of genetic risk, reflecting rule breaking and overt aggression, and 1 dimension of shared environmental risk, reflecting covert delinquency. These 3 familial factors differ meaningfully in their association with a range of relevant validators. PMID:23117573

  16. Mercury accumulation in yellow perch in Wisconsin seepage lakes: Relation to lake characteristics

    USGS Publications Warehouse

    Cope, W.G.; Wiener, J.G.; Rada, R.G.

    1990-01-01

    We studied relations between lacustrine characteristics and the total mercury (Hg) content of calendar age- 2 yellow perch (Perca flavescens ) in 10 seepage lakes in north-central Wisconsin. Mean concentrations and burdens (masses) of Hg in whole perch varied widely among lakes, were negatively correlated with lake pH and were positively correlated with total Hg concentration in surficial profundal sediment. Approximately 80 to 90% of the variation in Hg concentration and burden in whole perch was explained with multiple regressions containing two independent variables: either lake pH or alkalinity, and Hg concentration in surficial sediment. The mean concentration of Hg in axial muscle tissue of age-5 walleyes (Stizostedion vitreum vitreum ) from five of the study lakes was highly correlated with the mean concentration in whole age-2 perch in the same lakes.

  17. Perching and takeoff of a robotic insect on overhangs using switchable electrostatic adhesion.

    PubMed

    Graule, M A; Chirarattananon, P; Fuller, S B; Jafferis, N T; Ma, K Y; Spenko, M; Kornbluh, R; Wood, R J

    2016-05-20

    For aerial robots, maintaining a high vantage point for an extended time is crucial in many applications. However, available on-board power and mechanical fatigue constrain their flight time, especially for smaller, battery-powered aircraft. Perching on elevated structures is a biologically inspired approach to overcome these limitations. Previous perching robots have required specific material properties for the landing sites, such as surface asperities for spines, or ferromagnetism. We describe a switchable electroadhesive that enables controlled perching and detachment on nearly any material while requiring approximately three orders of magnitude less power than required to sustain flight. These electroadhesives are designed, characterized, and used to demonstrate a flying robotic insect able to robustly perch on a wide range of materials, including glass, wood, and a natural leaf. PMID:27199427

  18. Characterization and Extraction of Uranium Contamination Perched within the Deep Vadose Zone at the Hanford Site, Washington State

    NASA Astrophysics Data System (ADS)

    Williams, B. A.; Rohay, V. J.; Benecke, M. W.; Chronister, G. B.; Doornbos, M. H.; Morse, J.

    2012-12-01

    A highly contaminated perched water zone has been discovered in the deep vadose zone above the unconfined aquifer during drilling of wells to characterize groundwater contamination within the 200 East Area of the U.S. Department of Energy's Hanford Site in southeast Washington. The perched water, which contains nitrate, uranium, and technetium-99 at concentrations that have exceeded 100,000 μg/L, 70,000 μg/L, and 45,000 pCi/L respectively, is providing contamination to the underlying unconfined aquifer. A perched zone extraction well has been installed and is successfully recovering the contaminated perched water as an early remedial measure to reduce impacts to the unconfined aquifer. The integration and interpretation of various borehole hydrogeologic, geochemical, and geophysical data sets obtained during drilling facilitated the delineation of the perching horizon and determination of the nature and extent of the perched contamination. Integration of the borehole geologic and geophysical logs defined the structural elevation and thickness of the perching low permeability silt interval. Borehole geophysical moisture logs, gamma logs, and sample data allowed detailed determination of the elevation and thickness of the oversaturated zone above the perching horizon, and the extent and magnitude of the radiological uranium contamination within the perching interval. Together, these data sets resolved the nature of the perching horizon and the location and extent of the contaminated perched water within the perching zone, allowing an estimation of remaining contaminant extent. The resulting conceptual model indicates that the contaminated perched water is contained within a localized sand lens deposited in a structural low on top of a semi-regional low-permeability silt layer. The top of the sand lens is approximately 72 m (235 ft) below ground surface; the maximum thickness of the sand lens is approximately 3 m (10 ft). The lateral and vertical extent of the

  19. Factors influencing career choices in radiology trainees in Queensland, Australia.

    PubMed

    Ip, S W; Ko, H S; Applegate, K E

    2010-04-01

    The aim of this study was to investigate factors influencing career choices in radiology trainees. We distributed a 27-question written survey to all radiology registrars in Queensland. The questions investigated whether radiology was their first specialty choice, career satisfaction, ideal working conditions and attitudes regarding having children during the time of training. Forty-four of 51 surveys were returned (86% participation rate, 73% men, P = 0.048055) with 100% reporting a high job satisfaction; 28% of male registrars compared to 8% of female registrars did extra work outside of training to earn extra money (P = 0.000003), and 17% of female registrars took a leave of absence during their training, while no male registrar did (P = 0.087923). Only one female trainee worked part-time (P = 0.272727). In addition, 58% of female registrars planned a pregnancy (P = 0.731789) before completion of training; 83% of women versus 75% of men had no children (P = 0.329263). Only 5% of trainees agreed that it was easy to arrange part-time training, only 14% stated that it was easy to negotiate flexible work schedules and 7% agreed that it was easy to return to work after a period of absence. 'Time spent with immediate family' was rated the most important lifestyle factor, followed by 'work hours' and 'on-call duty'. The least important factors were 'being away from extended family', 'availability of part-time work' and whether 'work was in a rural location'. Overall job satisfaction is high among radiology trainees. Nevertheless, lifestyle factors, particularly those related to work time, are becoming more important for career decisions. This should be taken into account when designing and structuring radiology training to ensure that it is considered an attractive career choice. PMID:20518870

  20. Factors influencing the frequency of children's consumption of soft drinks.

    PubMed

    Pettigrew, Simone; Jongenelis, Michelle; Chapman, Kathy; Miller, Caroline

    2015-08-01

    Among other focus areas, interventions designed to improve children's diets need to address key factors contributing to children's consumption of sugar-sweetened beverages. The present study employed structural equation modelling to investigate the relationship between a broad range of predictor variables and the frequency with which Australian children consume soft drinks. In total, 1302 parents of children aged 8 to 14 years responded to an online survey about their children's food consumption behaviours. Soft drink consumption frequency was primarily influenced by parents' attitudes to soft drinks, children's pestering behaviours, and perceived social norms relating to children's consumption of these products. Importantly, pestering and social norms had significant direct effects on consumption frequency in addition to indirect effects via their impact on parents' attitudes to soft drink. PMID:25953597

  1. Factors influencing groundwater quality: towards an integrated management approach.

    PubMed

    De Giglio, O; Quaranta, A; Barbuti, G; Napoli, C; Caggiano, G; Montagna, M T

    2015-01-01

    The safety of groundwater resources is a serious issue, particularly when these resources are the main source of water for drinking, irrigation and industrial use in coastal areas. In Italy, 85% of the water used by the public is of underground origin. The aim of this report is to analyze the main factors that make groundwater vulnerable. Soil characteristics and filtration capacity can promote or hinder the diffusion of environmental contaminants. Global climate change influences the prevalence and degree of groundwater contamination. Anthropic pressure causes considerable exploitation of water resources, leading to reduced water availability and the progressive deterioration of water quality. Management of water quality will require a multidisciplinary, dynamic and practical approach focused on identifying the measures necessary to reduce contamination and mitigate the risks associated with the use of contaminated water resources.

  2. Climatic factors influencing triatomine occurrence in Central-West Brazil

    PubMed Central

    Pereira, Joyce Mendes; de Almeida, Paulo Silva; de Sousa, Adair Vieira; de Paula, Aécio Moraes; Machado, Ricardo Bomfim; Gurgel-Gonçalves, Rodrigo

    2013-01-01

    We estimated the geographic distributions of triatomine species in Central-West Region of Brazil (CW) and analysed the climatic factors influencing their occurrence. A total of 3,396 records of 27 triatomine species were analysed. Using the maximum entropy method, ecological niche models were produced for eight species occurring in at least 20 municipalities based on 13 climatic variables and elevation. Triatoma sordida and Rhodnius neglectus were the species with the broadest geographic distributions in CW Brazil. The Cerrado areas in the state of Goiás were found to be more suitable for the occurrence of synanthropic triatomines than the Amazon forest areas in the northern part of the state of Mato Grosso. The variable that best explains the evaluated models is temperature seasonality. The results indicate that almost the entire region presents climatic conditions that are appropriate for at least one triatomine species. Therefore, it is recommended that entomological surveillance be reinforced in CW Brazil. PMID:23778666

  3. [Greenhouse gas emission from reservoir and its influence factors].

    PubMed

    Zhao, Xiao-jie; Zhao, Tong-qian; Zheng, Hua; Duan, Xiao-nan; Chen, Fa-lin; Ouyang, Zhi-yun; Wang, Xiao-ke

    2008-08-01

    Reservoirs are significant sources of emissions of the greenhouse gases. Discussing greenhouse gas emission from the reservoirs and its influence factors are propitious to evaluate emission of the greenhouse gas accurately, reduce gas emission under hydraulic engineering and hydropower development. This paper expatiates the mechanism of the greenhouse gas production, sums three approaches of the greenhouse gas emission, which are emissions from nature emission of the reservoirs, turbines and spillways and downstream of the dam, respectively. Effects of greenhouse gas emission were discussed from character of the reservoirs, climate, pH of the water, vegetation growing in the reservoirs and so on. Finally, it has analyzed the heterogeneity of the greenhouse gas emission as well as the root of the uncertainty and carried on the forecast with emphasis to the next research.

  4. Factors Influencing Black Churches' Readiness to Address HIV.

    PubMed

    Pichon, Latrice C; Powell, Terrinieka Williams; Ogg, Siri A; Williams, Andrea L; Becton-Odum, Nicole

    2016-06-01

    This study employed a community-based participatory research approach to understand factors that influence church readiness to engage in HIV prevention and treatment activities. A convenience sample of twenty-six Black faith leaders participated in four focus groups. Data analysis was done through qualitative content analysis. Three themes emerged. First, the pastor's blessing and authority as the church's decision-maker determines readiness to engage in HIV prevention. Second, the church's purview of sexual health as part of a holistic ministry facilitates faith leader's readiness. Lastly, securing financial and human resources makes it feasible for faith leaders to implement activities. Findings suggest HIV-related stigma alone does not explain readiness to address HIV. Participants also discussed activities their churches are equipped to handle, including HIV testing events and health fairs.

  5. Factors influencing adoption of manure separation technology in The Netherlands.

    PubMed

    Gebrezgabher, Solomie A; Meuwissen, Miranda P M; Kruseman, Gideon; Lakner, Dora; Oude Lansink, Alfons G J M

    2015-03-01

    Manure separation technologies are essential for sustainable livestock operations in areas with high livestock density as these technologies result in better utilization of manure and reduced environmental impact. Technologies for manure separation have been well researched and are ready for use. Their use, however, has been limited to the Netherlands. This paper investigates the role of farm and farmer characteristics and farmers' attitudes toward technology-specific attributes in influencing the likelihood of the adoption of mechanical manure separation technology. The analysis used survey data collected from 111 Dutch dairy farmers in 2009. The results showed that the age and education level of the farmer and farm size are important variables explaining the likelihood of adoption. In addition to farm and farmer characteristics, farmers' attitudes toward the different attributes of manure separation technology significantly affect the likelihood of adoption. The study generates useful information for policy makers, technology developers and distributors in identifying the factors that impact decision-making behaviors of farmers.

  6. Factors influencing the declining trend of vasectomy in Sichuan, China.

    PubMed

    Nian, Cui; Xiaozhang, Liu; Xiaofang, Pan; Qing, Yang; Minxiang, Li

    2010-07-01

    Vasectomy was once the most common birth control method in both Sichuan Province, China and the world. However, since the 1990s the prevalence of vasectomy in Sichuan, has declined significantly compared to female sterilization in Sichuan and national prevalence of male/female sterilization during the same period. To explore possible reasons for this decline, 27 focus group discussions (FGDs) and 8 in-depth interviews (IDIs) were conducted in four strata of Sichuan. Procedures for qualitative data analysis were used. The findings reveal the decline in vasectomy in Sichuan Province is influenced by multiple factors, including shifts in demographics, changes in family planning working approach and people's perceptions of reproduction, lack of information and misunderstandings about vasectomy, the stereotype of male dominance, bias and preference of program and provider, and the impact of a market economy. Several implications arise from the study for future program development.

  7. Factors influencing the detection of beach plastic debris.

    PubMed

    Lavers, Jennifer L; Oppel, Steffen; Bond, Alexander L

    2016-08-01

    Marine plastic pollution is a global problem with considerable ecological and economic consequences. Quantifying the amount of plastic in the ocean has been facilitated by surveys of accumulated plastic on beaches, but existing monitoring programmes assume the proportion of plastic detected during beach surveys is constant across time and space. Here we use a multi-observer experiment to assess what proportion of small plastic fragments is missed routinely by observers, and what factors influence the detection probability of different types of plastic. Detection probability across the various types of plastic ranged from 60 to 100%, and varied considerably by observer, observer experience, and biological material present on the beach that could be confused with plastic. Blue fragments had the highest detection probability, while white fragments had the lowest. We recommend long-term monitoring programmes adopt survey designs accounting for imperfect detection or at least assess the proportion of fragments missed by observers. PMID:27363010

  8. Talking about Relations: Factors Influencing the Production of Relational Descriptions

    PubMed Central

    Baltaretu, Adriana; Krahmer, Emiel J.; van Wijk, Carel; Maes, Alfons

    2016-01-01

    In a production experiment (Experiment 1) and an acceptability rating one (Experiment 2), we assessed two factors, spatial position and salience, which may influence the production of relational descriptions (such as “the ball between the man and the drawer”). In Experiment 1, speakers were asked to refer unambiguously to a target object (a ball). In Experiment 1a, we addressed the role of spatial position, more specifically if speakers mention the entity positioned leftmost in the scene as (first) relatum. The results showed a small preference to start with the left entity, which leaves room for other factors that could influence spatial reference. Thus, in the following studies, we varied salience systematically, by making one of the relatum candidates animate (Experiment 1b), and by adding attention capture cues, first subliminally by priming one relatum candidate with a flash (Experiment 1c), then explicitly by using salient colors for objects (Experiment 1d). Results indicate that spatial position played a dominant role. Entities on the left were mentioned more often as (first) relatum than those on the right (Experiments 1a–d). Animacy affected reference production in one out of three studies (in Experiment 1d). When salience was manipulated by priming visual attention or by using salient colors, there were no significant effects (Experiments 1c, d). In the acceptability rating study (Experiment 2), participants expressed their preference for specific relata, by ranking descriptions on the basis of how good they thought the descriptions fitted the scene. Results show that participants preferred most the description that had an animate entity as the first mentioned relatum. The relevance of these results for models of reference production is discussed. PMID:26903911

  9. Factors influencing alternative splice site utilization in vivo.

    PubMed Central

    Fu, X Y; Manley, J L

    1987-01-01

    To study factors that influence the choice of alternative pre-mRNA splicing pathways, we introduced plasmids expressing either wild-type or mutated simian virus 40 (SV40) early regions into tissue culture cells and then measured the quantities of small-t and large-T RNAs produced. One important element controlling splice site selection was found to be the size of the intron removed in the production of small-t mRNA; expansion of this intron (from 66 to 77 or more nucleotides) resulted in a substantial increase in the amount of small-t mRNA produced relative to large-T mRNA. This suggests that in the normal course of SV40 early pre-mRNA processing, large-T splicing is at a competitive advantage relative to small-t splicing because of the small size of the latter intron. Several additional features of the pre-mRNA that can influence splice site selection were also identified by analyzing the effects of mutations containing splice site duplications. These include the strengths of competing 5' splice sites and the relative positions of splice sites in the pre-mRNA. Finally, we showed that the ratio of small-t to large-T mRNA was 10 to 15-fold greater in human 293 cells than in HeLa cells or other mammalian cell types. These results suggest the existence of cell-specific trans-acting factors that can dramatically alter the pattern of splice site selection in a pre-mRNA. Images PMID:3029566

  10. Information booklets about cancer: factors influencing patient satisfaction and utilization.

    PubMed

    Butow, P; Brindle, E; McConnell, D; Boakes, R; Tattersall, M

    1998-02-01

    Providing patients with adequate information is an important component of care. This exploratory study investigated factors influencing patient satisfaction with and utilization of information booklets. The research was conducted in two stages. In stage 1, five commonly used cancer information booklets were reviewed by 36 Australian patients who were either receiving chemotherapy or had just completed treatment. Data were collected on patient satisfaction with, preference for and utilization of information booklets. In addition data were collected on variables identified in the literature as potentially influencing patient satisfaction, including patient characteristics, presentation and readability of booklets, and the timing of provision. A high level of satisfaction was found for all five information booklets, although a clear preference for one particular booklet emerged. The most notable feature of this booklet was its readability level (grade 8); in contrast the other booklets were written at levels equivalent to grades 11-12. Stage 2 focused on the side effects of patient information preference style on their satisfaction and recall of information presented in two booklets in the course of their treatment. No differences were found between patients who seek information and those who avoid it. The findings of this study suggest that patients' information needs may be better met if information booklets are written in plain English, and presented to patients prior to treatment. Future studies incorporating a larger sample of patients and greater selection and variety of information booklets are required to further determine if patient characteristics and features of booklet presentation influence patient satisfaction and preference. PMID:9732653

  11. Factors influencing organic carbon preservation in marine sediments

    NASA Technical Reports Server (NTRS)

    Canfield, D. E.

    1994-01-01

    The organic matter that escapes decomposition is buried and preserved in marine sediments, with much debate as to whether the amount depends on bottom-water O2 concentration. One group argues that decomposition is more efficient with O2, and hence, organic carbon will be preferentially oxidized in its presence, and preserved in its absence. Another group argues that the kinetics of organic matter decomposition are similar in the presence and absence of O2, and there should be no influence of O2 on preservation. A compilation of carbon preservation shows that both groups are right, depending on the circumstances of deposition. At high rates of deposition, such as near continental margins, little difference in preservation is found with varying bottom-water O2. It is important that most carbon in these sediments decomposes by anaerobic pathways regardless of bottom-water O2. Hence, little influence of bottom-water O2 on preservation would, in fact, be expected. As sedimentation rate drops, sediments deposited under oxygenated bottom water become progressively more aerobic, while euxinic sediments remain anaerobic. Under these circumstances, the relative efficiencies of aerobic and anaerobic decomposition could affect preservation. Indeed, enhanced preservation is observed in low-O2 and euxinic environments. To explore in detail the factors contributing to this enhanced carbon preservation, aspects of the biochemistries of the aerobic and anaerobic process are reviewed. Other potential influences on preservation are also explored. Finally, a new model for organic carbon decomposition, the "pseudo-G" model, is developed. This model couples the degradation of refractory organic matter to the overall metabolic activity of the sediment, and has consequences for carbon preservation due to the mixing together of labile and refractory organic matter by bioturbation.

  12. Factors influencing dietary protein sources in the PREMIER trial population.

    PubMed

    Lin, Pao-Hwa; Miwa, Saki; Li, Yi-Ju; Wang, Yanfang; Levy, Erma; Lastor, Katherine; Champagne, Catherine

    2010-02-01

    Previous research suggests that protein intake, particularly plant protein, may benefit blood pressure control. However, very little has been published regarding protein sources in diets of US adults and factors influencing these choices. The purpose of this report is to describe specific sources of animal and plant proteins in diets of PREMIER clinical trial participants at baseline and how the PREMIER intervention, along with participant demographics, affected protein sources. Adult participants (n=809) who completed the 18-month PREMIER lifestyle intervention trial and had at least one diet recall at each of three study visits were included. Participants were recruited from four clinical centers in the Eastern, Southern, and Northeastern regions of United States. The PREMIER trial, conducted from 1999 to 2002, compared the impact on blood pressure of two structured behavioral interventions focusing on the traditional lifestyle modifications for blood pressure control with or without the Dietary Approaches to Stop Hypertension dietary pattern. Protein sources were assessed by two unannounced 24-hour recalls at each of three study visits. Differences in protein sources were mainly related to participant demographics, with relatively moderate impact of the intervention. The top four protein sources for all the study participants were poultry, dairy, refined grains and beef, each contributing approximately 10% to 17% in descending order to the total protein intake at baseline. Animal and plant protein each comprised approximately 66% and 34%, respectively, to the total daily protein intake at baseline, and such overall contribution pattern remained relatively constant over time. However, sex, race, age, and body weight status all influenced contribution patterns from different food groups significantly. These influences significantly impact choice and are essential elements to consider when designing intervention programs to alter protein contributions from animal

  13. Factors influencing success of dietitians employed in business and industry.

    PubMed

    Boudreaux, L J; Shanklin, C W; Johnson, J T

    1991-10-01

    Career opportunities in business and industry have been identified as one area of growth for the dietetics profession. The purposes of this study were to identify the skills, attributes, and knowledge areas dietitians need to succeed in business and industry; ascertain methods used to acquire these; assess factors that influenced career change; and determine the degree of perceived adequacy of academic preparation by practitioners employed in business and industry. A questionnaire, developed on the basis of a Delphi study involving 21 dietitians employed in business and industry, was administered to a national sample of 387 members of the Dietitians in Business and Industry (DIBI) dietetic practice group who were employed in business and industry. The overall response rate was 299 (77%); respondents were from 39 states. Skills, attributes, and knowledge areas were identified for specific employment classifications in business and industry. Self-motivation and work experience in business were identified as the most important methods for acquiring skills for this area of practice. Challenge of a new position and diversity of job responsibilities had the most influence on career change of respondents. Undergraduate and graduate education were rated somewhat inadequate and adequate, respectively, by the majority of respondents. The findings indicate that positions in business and industry require specific skills, attributes, and knowledge that may not necessarily be attained through traditional approaches. Self-assessment and appropriate self-development activities are essential for success.

  14. Factors that influence the acrylamide content of heated foods.

    PubMed

    Rydberg, Per; Eriksson, Sune; Tareke, Eden; Karlsson, Patrik; Ehrenberg, Lar; Törnqvist, Margareta

    2005-01-01

    Our finding that acrylamide is formed during heating of food initiated a range of studies on the formation of acrylamide. The present paper summarizes our follow-up studies on the characterization of parameters that influence the formation and degradation of acrylamide in heated foods. The system designed and used for studies of the influence of added factors was primarily homogenized potato heated in an oven. The net content of acrylamide after heating was examined with regard to the following parameters: heating temperature, duration of heating, pH and concentrations of various components. Higher temperature (200 degrees C) combined with prolonged heating led to reduced levels of acrylamide, due to elimination/degradation processes. At certain concentrations, the presence of asparagine or monosaccharides (in particular fructose, glucose and glyceraldehyde) was found to increase the net content of acrylamide. Addition of other free amino acids or a protein-rich food component strongly reduced the acrylamide content, probably by promoting competing reactions and/or covalently binding of formed acrylamide. The pH-dependence of acrylamide formation exhibited a maximum around pH 8; lower pH enhanced elimination and decelerated formation of acrylamide. In contrast, the effects of additions of antioxidants or peroxides on acrylamide content were not significant. The acrylamide content of heated foods is the net result of complex reactions leading to both the formation and elimination/degradation of this molecule.

  15. Factors influencing teacher decisions on school, classroom, and curriculum

    NASA Astrophysics Data System (ADS)

    Crocker, Robert K.; Banfield, Helen

    This article describes a study designed to explore sources of influence on the judgments made by science teachers on school characteristics, classroom features, and properties of a science curriculum. The study had its theoretical basis in the concept that members of a social organization operate under certain functional paradigms, which govern their approach to events within the organization, and particularly to the implementation of innovations. Empirically, the study formed part of the Canadian contribution to the Second International Science Study, and was based on a survey of some 2000 Canadian teachers. The survey used an adaptation of policy capturing methodology, in which teachers were presented with variations in a hypothetical scenario designed to simulate a decision-making situation. Results suggest that teachers' judgments center around a number of factors, the primary ones being concern for student ability and interest, teaching methods, and school spirit and morale. On the other hand, variations in the scientific basis of a curriculum appear to exert little influence. The results are interpreted as indicators of the major elements of teacher functional paradigms.

  16. Investigation of groundwater recirculation for the removal of RDX from the Pantex Plant perched aquifer

    SciTech Connect

    Woods, A.L.; Barnes, D.L.; Boles, K.M.; Charbeneau, R.J.; Black, S.; Rainwater, K.

    1998-07-01

    The Pantex Plant near Amarillo, Texas, is a US Department of Energy (DOE) facility that has been in operation since 1942. Past and present operations at Pantex include the creation of chemical high explosives components for nuclear weapons and assembly and disassembly of nuclear weapons. The Pantex Plant is underlain by the Ogallala aquifer, which in this area, consists of the main water-bearing unit and a perched water zone. These are separated by a fine-grained zone of low permeability. Multiple contaminant plumes containing high explosive (HE) compounds have been detected in the perched aquifer beneath the plant. The occurrence of these contaminants is the result of past waste disposal practices at the facility. RDX is an HE compound, which has been detected in the groundwater of the perched aquifer at significant concentrations. A pilot-scale, dual-phase extraction treatment system has been installed at one location at the plant, east of Zone 12, to test the effectiveness of such a system on the removal of these contaminants from the subsurface. A tracer test using a conservative tracer, bromide (Br), was conducted at the treatment site in 1996. In addition to the bromide, RDX and water elevations in the aquifer were monitored. Using data from the tracer test and other relevant data from the investigations at Pantex, flow and contaminant transport in the perched aquifer were simulated with groundwater models. The flow was modeled using MODFLOW and the transport of contaminants in the aqueous phase was modeled using MT3D. Modeling the perched aquifer had been conducted to characterize the flow in the perched aquifer; estimate RDX retardation in the perched aquifer; and evaluate the use of groundwater re-circulation to enhance the extraction of RDX from the perched aquifer.

  17. Nitrate-nitrogen concentrations in the perched ground water under seepage-irrigated potato cropping systems.

    PubMed

    Munoz-Arboleda, F; Mylavarapu, R; Hutchinson, C; Portier, K

    2008-01-01

    Excessive nitrogen rates for potato production in northeast Florida have been declared as a potential source of nitrate pollution in the St. Johns River watershed. This 3-yr study examined the effect of N rates (0, 168, and 280 kg ha(-1)) split between planting and 40 d after planting on the NO(3)-N concentration in the perched ground water under potato (Solanum tuberosum cv. Atlantic) in rotation with sorghum sudan grass hybrid (Sorghum vulgare x Sorghum vulgare var. sudanese, cv. SX17), cowpea (Vigna unguiculata cv. Iron Clay), and greenbean (Phaseolus vulgare cv. Espada). Soil solution from the root zone and water from the perched ground water under potato were sampled periodically using lysimeters and wells, respectively. Fertilization at planting increased the NO(3)-N concentration in the perched ground water, but no effect of the legumes in rotation with potatoes on nitrate leaching was detected. Fertilization of green bean increased NO(3)-N concentration in the perched ground water under potato planted in the following season. The NO(3)-N concentration in the soil solution within the potato root zone followed a similar pattern to that of the perched ground water but with higher initial values. The NO(3)-N concentration in the perched ground water was proportional to the rainfall magnitude after potato planting. A significant increase in NO(3)-N concentration in the perched ground water under cowpea planted in summer after potato was detected for the side-dressing of 168 kg ha(-1) N applied to potato 40 d after planting but not at the 56 kg ha(-1) N side-dress. Elevation in NO(3)-N concentration in the perched ground water under sorghum was not significant, supporting its use as an effective N catch crop.

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

    USGS Publications Warehouse

    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.

  19. Soft Perches in an Aviary System Reduce Incidence of Keel Bone Damage in Laying Hens

    PubMed Central

    Stratmann, Ariane; Fröhlich, Ernst K. F.; Harlander-Matauschek, Alexandra; Schrader, Lars; Toscano, Michael J.; Würbel, Hanno; Gebhardt-Henrich, Sabine G.

    2015-01-01

    Keel bone fractures and deviations are one of the major welfare and health issues in commercial laying hens. In non-cage housing systems like aviaries, falls and collisions with perches and other parts of the housing system are assumed to be one of the main causes for the high incidence of keel bone damage. The objectives of this study were to investigate the effectiveness of a soft perch material to reduce keel bone fractures and deviations in white (Dekalb White) and brown laying hens (ISA Brown) kept in an aviary system under commercial conditions. In half of 20 pens, all hard, metal perches were covered with a soft polyurethane material. Palpation of 20 hens per pen was conducted at 18, 21, 23, 30, 38, 44 and 64 weeks of age. Production data including egg laying rate, floor eggs, mortality and feed consumption were collected over the whole laying period. Feather condition and body mass was assessed twice per laying period. The results revealed that pens with soft perches had a reduced number of keel bone fractures and deviations. Also, an interaction between hybrid and age indicated that the ISA hybrid had more fractured keel bones and fewer non-damaged keel bones compared with the DW hybrid at 18 weeks of age, a response that was reversed at the end of the experiment. This is the first study providing evidence for the effectiveness of a soft perch material within a commercial setting. Due to its compressible material soft perches are likely to absorb kinetic energy occurring during collisions and increase the spread of pressure on the keel bone during perching, providing a mechanism to reduce keel bone fractures and deviations, respectively. In combination with genetic selection for more resilient bones and new housing design, perch material is a promising tool to reduce keel bone damage in commercial systems. PMID:25811980

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

    PubMed

    Palmer, Alexander D; Emmenegger, Eveline J

    2014-06-01

    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 (10(6) PFU/fish) and by immersion (5.7×10(5) 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 (<6%) compared with steelhead (>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.

  1. The effect of perch availability during pullet rearing and egg laying on musculoskeletal health of caged White Leghorn hens.

    PubMed

    Hester, P Y; Enneking, S A; Haley, B K; Cheng, H W; Einstein, M E; Rubin, D A

    2013-08-01

    A major skeletal problem of conventionally caged hens is increased susceptibility to osteoporosis mainly due to lack of exercise. Osteoporosis is characterized by a progressive decrease in mineralized structural bone. Whereas considerable attention has been given to enriching laying cages, little research has been conducted on providing caged pullets with furnishments, in particular perches. The objective of the current study was to determine if metal perches during all or part of the life cycle of White Leghorns affected hen musculoskeletal health, especially at end of lay. Treatments during the pullet phase (hatch to 16.9 wk) entailed cages with and without perches. Four treatments were used during the laying phase (17 to 71 wk of age). Treatment 1 chickens never had access to perches at any point during their life cycle, typical of egg industry practices in the United States for conventional cages. Treatment 2 chickens had access to perches only during the egg-laying phase, which was from 17 to 71 wk of age. Treatment 3 chickens had access to perches only during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had perch access throughout their entire life cycle (0 to 71 wk of age). Musculoskeletal health was assessed by measuring muscle weights, bone mineralization, bone fracture incidence, and keel bone deviations. Muscle deposition of 71-wk-old hens increased when given access to perches as pullets. Bone mineralization of 71-wk-old hens also increased if given perch access as adults. However, the disadvantage of the adult perch was the higher incidence of keel deviations and keel fractures at end of lay. The increase in bone mineralization of the keel bone as a result of perch access during the pullet and laying phases was not great enough to prevent a higher incidence of keel bone fractures at end of lay. Perch redesign and placement of perches within the cage to minimize keel fractures and deviations are possible solutions. PMID:23873543

  2. Fish community dynamics in northeastern Lake Ontario with emphasis on the growth and reproductive success of yellow perch (Perca flavescens) and white perch (Morone americana), 1978 to1997

    USGS Publications Warehouse

    O'Gorman, Robert; Burnett, John A.D.

    2001-01-01

    Fishes were assessed in Guffin, Chaumount, and Black River bays in northeastern Lake Ontario with a 7.9-m (headrope) bottom trawl during late September and early October, 1978 to 1997. Fish density declined in the early 1990s with sharp declines in abundance of spottail shiner (Notropis hudsonius), trout-perch (Percopsis omiscomaycus), and johnny darter (Etheostoma nigrum) occurring in 1993 to 1995. Rising numbers of piscivores, walleye (Stizostedion vitreum) and double-crested cormorant (Phalacrocorax auritus), increased predation pressure, presumably acting in concert with oligotrophication to lower fish density, particularly after 1991 when large numbers of adult alewife (Alosa pseudoharengus) no longer migrated to the northeast basin in spring. Annual mortality of yellow perch (Perca flavescens) from age 2 to 5 rose from 33% in 1980–83 to 65% in 1992–95 and was positively related to piscivore numbers (P = 0.01, r = 0.96, n = 5). Annual mortality of yellow perch from age 0 to 2 also peaked in 1992–95. Abundance of yellow perch YOY in fall varied 40 fold and was not related to water warming in spring (P = 0.45, r = −0.19, n = 18) but was negatively related to the abundance of adult alewives in spring (P = 0.04, r = −0.49, n = 18). Although yellow perch produced moderate to strong year classes each year during 1991–95, stock size failed to increase because of rapidly accelerating mortality. Fully 85% of the variation in mean length of yellow perch YOY was explained by a multiple regression model which included YOY abundance, mean total phosphorus, and cumulative degree days > 13.5°C (P < 0.01, n = 15). Abundance of white perch (Morone americana) YOY varied nearly 200 fold and was not related to water warming or spring alewife abundance (P > 0.15). Variation in mean length of white perch YOY was related to cumulative degree days > 15°C (P < 0.01, r = 0.69).

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

    SciTech Connect

    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.

  4. Extrinsic Factors Influencing Fetal Deformations and Intrauterine Growth Restriction

    PubMed Central

    Moh, Wendy; Graham, John M.; Wadhawan, Isha; Sanchez-Lara, Pedro A.

    2012-01-01

    The causes of intrauterine growth restriction (IUGR) are multifactorial with both intrinsic and extrinsic influences. While many studies focus on the intrinsic pathological causes, the possible long-term consequences resulting from extrinsic intrauterine physiological constraints merit additional consideration and further investigation. Infants with IUGR can exhibit early symmetric or late asymmetric growth abnormality patterns depending on the fetal stage of development, of which the latter is most common occurring in 70–80% of growth-restricted infants. Deformation is the consequence of extrinsic biomechanical factors interfering with normal growth, functioning, or positioning of the fetus in utero, typically arising during late gestation. Biomechanical forces play a critical role in the normal morphogenesis of most tissues. The magnitude and direction of force impact the form of the developing fetus, with a specific tissue response depending on its pliability and stage of development. Major uterine constraining factors include primigravida, small maternal size, uterine malformation, uterine fibromata, early pelvic engagement of the fetal head, aberrant fetal position, oligohydramnios, and multifetal gestation. Corrective mechanical forces similar to those that gave rise to the deformation to reshape the deformed structures are often used and should take advantage of the rapid postnatal growth to correct form. PMID:22888434

  5. Genetic and epigenetic factors influencing chronic kidney disease.

    PubMed

    Smyth, L J; Duffy, S; Maxwell, A P; McKnight, A J

    2014-10-01

    Chronic kidney disease (CKD) has become a serious public health problem because of its associated morbidity, premature mortality, and attendant healthcare costs. The rising number of persons with CKD is linked with the aging population structure and an increased prevalence of diabetes, hypertension, and obesity. There is an inherited risk associated with developing CKD, as evidenced by familial clustering and differing prevalence rates across ethnic groups. Previous studies to determine the inherited risk factors for CKD rarely identified genetic variants that were robustly replicated. However, improvements in genotyping technologies and analytic methods are now helping to identify promising genetic loci aided by international collaboration and multiconsortia efforts. More recently, epigenetic modifications have been proposed to play a role in both the inherited susceptibility to CKD and, importantly, to explain how the environment dynamically interacts with the genome to alter an individual's disease risk. Genome-wide, epigenome-wide, and whole transcriptome studies have been performed, and optimal approaches for integrative analysis are being developed. This review summarizes recent research and the current status of genetic and epigenetic risk factors influencing CKD using population-based information.

  6. Factors influencing STI transmission in middle-aged heterosexual individuals.

    PubMed

    Monsell, Ellen; McLuskey, John

    2016-06-23

    Research has shown that individuals aged 45-64, or the 'middle-aged' population, are at an increasing risk of contracting a sexually transmitted infection (STI). An exploration of the factors that may influence STIs in this age group was carried out to ascertain how to reduce the risk. A critical review identified 14 research papers that considered STIs in middle-aged people. The available evidence base highlighted an under-representation of women, the absence of a consistent definition of 'middle age', and a paucity of specific information on the sexual health needs of this group. Low condom use was found to be a possible contributor to increasing STI rates; men were shown to report particularly low use. Behaviours such as contact with sex workers and sexual encounters abroad were found to be additional risk factors in men, requiring further consideration. The breakdown and formation of relationships during middle age was also identified as a possible area to investigate, as were the behavioural traits of women and associated STI risk. Further research into these areas could facilitate the development of attitudes, knowledge, policy and practice that could help provide better support for individuals affected. PMID:27345071

  7. Toilet training age and influencing factors: a multicenter study.

    PubMed

    Tarhan, Hüseyin; Çakmak, Özgür; Akarken, İlker; Ekin, Rahmi Gökhan; Ün, Sıtkı; Uzelli, Derya; Helvacı, Mehmet; Aksu, Nejat; Yavaşcan, Önder; Mutlubaş Özsan, Fatma; Cun, Selma; Koç, Feyza; Özkarakaş, Özlem; İlbey, Yusuf Özlem; Zorlu, Ferruh

    2015-01-01

    To determine toilet training age and the factors influencing this in our country, 1500 children who had completed toilet training were evaluated in a multicenter study. The mean age of toilet training was 22.32 ± 6.57 months. The duration it took to complete toilet training was 6.60 ± 2.20 months on the average. In univariant analysis, toilet training age increased as the parental education level, specifically that of the mother, increased. The training age of children whose mothers had over 12 years of education differed significantly from that of children of mothers with less education. There was no significant difference in toilet training age with regard to the education level of the father, or the employment status of the mother. We also found significant differences with respect to family income level, toilet type and training method. In multivariant analysis, family income >5000 TL and use of a potty chair were determined to be factors affecting toilet training age. In conclusion, toilet training age in Turkey, a developing country, was found to be lower than that in developed countries.

  8. Influence of abiotic factors on the antimicrobial activity of chitosan.

    PubMed

    Tavaria, Freni K; Costa, Eduardo M; Gens, Eduardo J; Malcata, Francisco Xavier; Pintado, Manuela E

    2013-12-01

    In an effort to bypass the adverse secondary effects attributed to the traditional therapeutic approaches used to treat skin disorders (such as atopic dermatitis), alternative antimicrobials have recently been suggested. One such antimicrobial is chitosan, owing to the already proved biological properties associated with its use. However, the influence of abiotic factors on such activities warrants evaluation. This research effort assessed the antimicrobial activity of chitosan upon skin microorganisms (Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli) in vitro when subject to a combination of different abiotic factors such as pH, ionic strength, organic acids and free fatty acids. Free fatty acids, ionic strength and pH significantly affected chitosan's capability of reducing the viable numbers of S. aureus. This antimicrobial action was potentiated in the presence of palmitic acid and a lower ionic strength (0.2% NaCl), while a higher ionic strength (0.4% NaCl) favored chitosan's action upon the reduction of viable numbers of S. epidermidis and E. coli. Although further studies are needed, these preliminary results advocate that chitosan can in the future be potentially considered as an antimicrobial of choice when handling symptoms associated with atopic dermatitis.

  9. Physical Activity in Adolescents following Treatment for Cancer: Influencing Factors.

    PubMed

    Wright, Marilyn; Bryans, Angie; Gray, Kaylin; Skinner, Leah; Verhoeve, Amanda

    2013-01-01

    The purpose of this study was to examine physical activity levels and influencing individual and environmental factors in a group of adolescent survivors of cancer and a comparison group. Methods. The study was conducted using a "mixed methods" design. Quantitative data was collected from 48 adolescent survivors of cancer and 48 comparison adolescents using the Godin Leisure-Time Exercise Questionnaire, the Fatigue Scale-Adolescents, and the Amherst Health and Activity Study-Student Survey. Qualitative data was collected in individual semistructured interviews. Results. Reported leisure-time physical activity total scores were not significantly different between groups. Physical activity levels were positively correlated with adult social support factors in the group of adolescent survivors of cancer, but not in the comparison group. Time was the primary barrier to physical activity in both groups. Fatigue scores were higher for the comparison but were not associated with physical activity levels in either group. The qualitative data further supported these findings. Conclusions. Barriers to physical activity were common between adolescent survivors of cancer and a comparative group. Increased knowledge of the motivators and barriers to physical activity may help health care providers and families provide more effective health promotion strategies to adolescent survivors of pediatric cancer.

  10. The hazard of sharp force injuries: Factors influencing outcome.

    PubMed

    Kristoffersen, Stine; Normann, Stig-André; Morild, Inge; Lilleng, Peer Kåre; Heltne, Jon-Kenneth

    2016-01-01

    The risk of dying from sharp force injury is difficult to ascertain. To the best of our knowledge, no study has been performed in Norway regarding mortality due to sharp force injury or factors that impact survival. Thus, the objective of the present study was to investigate and assess mortality in subjects with sharp force injury. This retrospective study comprises data on 136 subjects (34 female, 102 male) with suspected severe sharp force injury (self-inflicted or inflicted by others) admitted to Haukeland University Hospital between 2001 and 2010. The majority of subjects were intoxicated, and the injury was most often inflicted by a knife. The incidence of sharp force injury in Western Norway is similar to the incidence in other European countries. Almost half of the subjects with self-inflicted injury died. In cases with injury inflicted by another individual, one in five died. Mortality rates were higher in those with penetrating chest injuries than those with penetrating abdominal injuries and higher in cases with cardiac injury compared to pleural or lung injury. Sharp force injury can be fatal, but the overall mortality rate in this study was 29%. Factors influencing mortality rate were the number of injuries, the topographic regions of the body injured, the anatomical organs/structures inflicted, and emergency measures performed.

  11. Identifying influencing factors on paved roads silt loading.

    PubMed

    Teng, Hualiang; Kwigizile, Valerian; James, David E; Merle, Russell

    2007-07-01

    The factors that influence the increase or decrease of silt loadings on paved roadways have not been fully quantitatively investigated. They were identified in this study based on the quarterly silt loading sampling data collected from 20 sites by the Clark County Department of Air Quality and Environmental Management in Southern Nevada for the period from 2000 to 2003. The silt loading and associated data collected over these years at one sampling site may inherently possess site-specific characteristics that can be better incorporated by using panel data models. The factors that are identified as significant are the presence of curbs and gutters, shoulder type, pavement conditions, and the presence of construction activities in the vicinity of roadways. The presence of curbs and gutters, stabilized shoulders, and good pavement conditions would result in decreased silt loadings. Conversely, the presence of construction activities within the immediate vicinity of sampled areas would result in increases of silt loadings on the roadway surfaces. Based on the analysis of the results, it was recommended that constructing curbs, gutters and stabilized shoulders, preventing or reducing construction track-out from construction activity, and improving pavement conditions be the preferred control measures to reduce silt loading on paved roadways. PMID:17687992

  12. Factors influencing the antibody response to vaccination against rabies.

    PubMed

    Jakel, V; König, M; Cussler, K; Hanschmann, K; Thiel, H-J

    2008-01-01

    Preventive vaccination against rabies virus is a highly effective method for preventing rabies in humans and animals. For travel purposes, vaccination of domestic carnivores is obligatory. In addition, some countries require testing for neutralizing antibodies against rabies. The minimal threshold level accepted by WHO/OIE is 0.5 IU/ml. Despite proper vaccination some animals do not reach the threshold. The objective of this study was to identify specific risk factors in dogs and cats for post-vaccination rabies antibody titres below 0.5 IU/ml by FAVN test. Rabies vaccination protocols and recommendations were reviewed with regard to travel regulations. Comprehensive data was collected on animals tested for rabies antibodies via a questionnaire sent to veterinarians who submitted sera for rabies titration. The questionnaire included data on species, age, sex, breed, vaccine used, date of last vaccination and blood sampling, vaccination history and further medical treatments at time of vaccination. Data on around 1,200 animals was analysed. Most animals older than one year had already received more than one rabies vaccination. The influence of breed and sex on antibody titre seems to be insignificant. Young dogs have a high risk of results below 0.5 IU/ml after their first vaccination. This risk can be minimised by the application of a second vaccination and blood sampling according to the manufacturer's recommendations. An important factor for the test outcome might be the virus strain used in the vaccine.

  13. Factors influencing prognosis in adults with acute myelogenous leukaemia.

    PubMed Central

    Crowther, D.; Beard, M. E.; Bateman, C. J.; Sewell, R. L.

    1975-01-01

    A study of the thymidine labelling index (TLI) of bone marrow blast cells in 58 untreated patients with acute myelogenous leukemia showed no correlation with remission rate but there was a strong correlation between labelling index and remission length in the 21 patients who achieved remission. The median remission length of the patients was 33 weeks. Of the 12 patients with initial labelling indices greater than 10%, only 2 had remissions longer than 33 weeks whereas 8 of the 9 patients with labelling indices less than 10% had remissions longer than 33 weeks. No correlation could be found between the degree of cytological differentiation and remission induction, remission length or survival. No correlation was found between the TLI and the degree of cytological differentiation. Age and initial platelet count were confirmed to be important factors influencing complete remission rate, but these factors did not correlate with remission length. Sixteen patients had their pretreatment sera assayed for mouse marrow colony stimulating activity and inhibitor levels but there was no correlation with subsequent response to treatment, although the number of patients examined was clearly too small for any definite conclusions to be drawn. PMID:1082343

  14. Impaired glucose tolerance: influence by environmental and hereditary factors.

    PubMed

    Cederholm, J; Wibell, L

    1991-01-01

    The influence on impaired glucose tolerance (IGT) by obesity, physical leisure time activity (PLTA), family histories of diabetes mellitus (DM) and other characteristics were evaluated in a health survey of 807 middle-aged females and males, with the rate of IGT 8.4% (WHO-criteria). Independent (adjusted for covariates) odds ratios concerning IGT were estimated. The ratios were 5.3 with the presence of obesity and 2.2. (ns) with low compared to high PLTA. In a subgroup of summarized environmental factors (obesity and low PLTA versus no obesity and high PLTA, n = 339), the independent odds ratio for IGT was 9.6 with obesity and low PLTA. With one 1st degree DM relative the odds ratio for IGT was 3.1. The ratio was increased both with the presence of relatives with non-insulin-dependent diabetes mellitus and with the presence of relatives with insulin-treated diabetes. Diabetic mothers yielded a higher ratio for IGT than diabetic fathers. In conclusion, the independent relative risk for IGT in this Swedish middle-aged urban sample was about two times higher with environmental factors (obesity only/obesity with low PLTA) than with one 1st degree DM relative.

  15. Identifying influencing factors on paved roads silt loading.

    PubMed

    Teng, Hualiang; Kwigizile, Valerian; James, David E; Merle, Russell

    2007-07-01

    The factors that influence the increase or decrease of silt loadings on paved roadways have not been fully quantitatively investigated. They were identified in this study based on the quarterly silt loading sampling data collected from 20 sites by the Clark County Department of Air Quality and Environmental Management in Southern Nevada for the period from 2000 to 2003. The silt loading and associated data collected over these years at one sampling site may inherently possess site-specific characteristics that can be better incorporated by using panel data models. The factors that are identified as significant are the presence of curbs and gutters, shoulder type, pavement conditions, and the presence of construction activities in the vicinity of roadways. The presence of curbs and gutters, stabilized shoulders, and good pavement conditions would result in decreased silt loadings. Conversely, the presence of construction activities within the immediate vicinity of sampled areas would result in increases of silt loadings on the roadway surfaces. Based on the analysis of the results, it was recommended that constructing curbs, gutters and stabilized shoulders, preventing or reducing construction track-out from construction activity, and improving pavement conditions be the preferred control measures to reduce silt loading on paved roadways.

  16. Factors influencing HIV vaccine community engagement in the urban South.

    PubMed

    Frew, Paula M; del Rio, Carlos; Clifton, Sarah; Archibald, Matthew; Hormes, Joseph T; Mulligan, Mark J

    2008-08-01

    The purpose of this exploratory study was to examine personal characteristics, socio-environmental conditions, and motivational factors that potentially influence HIV vaccine research community engagement. Specifically, the study identified predictive aspects that may aid in future community program development on HIV vaccine issues. A cross-sectional survey consisting of evaluative measures, demographics, social interaction, and health information-seeking behaviors was conducted. Participants were a diverse group of 452 adults (>or=18 years) at HIV vaccine awareness-building and community education gatherings in Atlanta. The sample included large numbers of women (n=251) and minorities (n=224). In multivariate analysis, the overall logistic regression model was significant, with a resulting coefficient of determination (Nagelkerke R(2)) of .505. Highly significant factors included an excellent activity/event rating (log odds beta = 4.521, P< .001), White race (beta= -.835, P= .005), greater educational attainment (beta= .725, P= .011), travel distance (beta = 1.186, P= .002), and excellent perception of the study site (beta=2.131, P< .001). Subgroup analyses by gender and race revealed similar findings. These data demonstrate the importance of building a favorable study site image and gaining familiarity in the community to aid in the promotion of HIV vaccine research on an ongoing basis. PMID:18389351

  17. Influence of abiotic factors on the antimicrobial activity of chitosan.

    PubMed

    Tavaria, Freni K; Costa, Eduardo M; Gens, Eduardo J; Malcata, Francisco Xavier; Pintado, Manuela E

    2013-12-01

    In an effort to bypass the adverse secondary effects attributed to the traditional therapeutic approaches used to treat skin disorders (such as atopic dermatitis), alternative antimicrobials have recently been suggested. One such antimicrobial is chitosan, owing to the already proved biological properties associated with its use. However, the influence of abiotic factors on such activities warrants evaluation. This research effort assessed the antimicrobial activity of chitosan upon skin microorganisms (Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli) in vitro when subject to a combination of different abiotic factors such as pH, ionic strength, organic acids and free fatty acids. Free fatty acids, ionic strength and pH significantly affected chitosan's capability of reducing the viable numbers of S. aureus. This antimicrobial action was potentiated in the presence of palmitic acid and a lower ionic strength (0.2% NaCl), while a higher ionic strength (0.4% NaCl) favored chitosan's action upon the reduction of viable numbers of S. epidermidis and E. coli. Although further studies are needed, these preliminary results advocate that chitosan can in the future be potentially considered as an antimicrobial of choice when handling symptoms associated with atopic dermatitis. PMID:24330167

  18. Understanding the factors influencing safe and unsafe motorcycle rider intentions.

    PubMed

    Tunnicliff, Deborah J; Watson, Barry C; White, Katherine M; Hyde, Melissa K; Schonfeld, Cynthia C; Wishart, Darren E

    2012-11-01

    The increasing popularity of motorcycles in Australia is a significant concern as motorcycle riders represent 15% of all road fatalities and an even greater proportion of serious injuries. This study assessed the psychosocial factors influencing motorcycle riders' intentions to perform both safe and risky riding behaviours. Using an extended theory of planned behaviour (TPB), motorcycle riders (n=229) from Queensland, Australia were surveyed to assess their riding attitudes, subjective norm (general and specific), perceived behavioural control (PBC), group norm, self-identity, sensation seeking, and aggression, as well as their intentions, in relation to three safe (e.g., handle my motorcycle skilfully) and three risky (e.g., bend road rules to get through traffic) riding behaviours. Although there was variability in the predictors of intention across the behaviours, results revealed that safer rider intentions were most consistently predicted by PBC, while riskier intentions were predicted by attitudes and sensation seeking. The TPB was able to explain a greater proportion of the variance for intentions to perform risky behaviours. Overall, this study has provided insight into the complexity of factors contributing to rider intentions and suggests that different practical strategies need to be adopted to facilitate safer and reduce risky rider decisions. PMID:23036390

  19. Factors Influencing Deoxynivalenol Accumulation in Small Grain Cereals

    PubMed Central

    Wegulo, Stephen N.

    2012-01-01

    Deoxynivalenol (DON) is a mycotoxin produced by the plant pathogenic fungi Fusarium graminearum and F. culmorum. These and other closely related fungi cause a disease known as Fusarium head blight (FHB) in small grain cereals. Other mycotoxins produced by FHB-causing fungi include nivalenol, T-2 toxin, and zearalenone. Ingestion of mycotoxin-contaminated food and feed can lead to toxicosis in humans and animals, respectively. DON is the predominant and most economically important of these mycotoxins in the majority of small grain-producing regions of the world. This review examines the factors that influence DON accumulation in small grain cereals from an agricultural perspective. The occurrence and economic importance of FHB and DON in small grain cereals, epidemiological factors and cereal production practices that favor FHB development and DON accumulation in grain under field conditions, and regulatory/advisory standards for DON in food and feed are discussed. This information can be used to develop strategies that reduce DON accumulation in grain before harvest and to mitigate the human and animal health risks associated with DON contamination of food and feed. PMID:23202310

  20. Factors influencing adolescents engagement in risky Internet behavior.

    PubMed

    Liau, Albert Kienfie; Khoo, Angeline; Ang, Peng Hwa

    2005-12-01

    The present study used data from the SAFT (Safety, Awareness, Facts and Tools) Singapore survey, a national survey of 1,124 youths aged 12-17, to explore the issue of risk on the Internet. We investigated factors that influence adolescents' engagement in risky Internet behavior, in particular, meeting face-to-face someone they first encountered online. The adolescents ranged from ages 12 to 17, with a mean of 14.32 (SD = 1.37); 49.6% of the adolescents were girls. The study utilized a 93-item survey that was part of the SAFT Project. Results indicated that 16% of adolescent Internet users in Singapore have had a face-to-face meeting with someone first encountered online. The following factors were found to be predictors of adolescents engagement in such face-to-face meetings: age, frequency of Internet use, frequency of chatting and gaming behavior, parental rules, type of personal information given out, amount of inappropriate messages received, whether inappropriate websites have been visited, and type of internet advice heard. Implications of the results are discussed.

  1. Molecular characterization of the myosatin gene and the effect of fasting on its expression in Chinese perch (Siniperca chuatsi).

    PubMed

    Liu, L; Li, Y L; Xu, S D; Wang, K Z; Wu, P; Chu, W Y; Wang, X Q

    2016-01-01

    Myostatin (MSTN) is an important member of the transforming growth factor-β (TGF-β) superfamily and is a muscle growth inhibitor. In the present study, we cloned the Chinese perch MSTN cDNA sequence and analyzed its expression patterns under various conditions. The MSTN full cDNA sequence was 3347 bp long, including an open-reading frame of 1131 bp, which encoded 376 amino acids. Sequence analysis demonstrated that the MSTN shared a highly conserved signal peptide, a TGF-β functional peptide, a hydrolytic site (RARR), and nine conservative cysteine residues with other members of the TGF-β superfamily. Sequence alignment and phylogenetic tree analyses indicated that the MSTN had a close relationship with teleostean fish, but they are far separated from mammals. Real-time polymerase chain reaction analysis revealed that the MSTN was strongly expressed in the skeletal muscle and heart tissues. Temporal expression analysis demonstrated that the MSTN gene was expressed in very low levels, from 20 to 90 dph (post-hatching development), and was at its highest level at 150 dph (P < 0.05). The fasting-re-feeding experiment showed that the expression of the MSTN gene was initially decreased in response to a single meal, after seven days of fasting, and subsequently increased significantly, and finally decreased back to its original level. Together, our results provided valuable knowledge regarding the regulation of MSTN gene expression in Chinese perch. PMID:27173303

  2. Sow and litter factors influencing colostrum yield and nutritional composition.

    PubMed

    Declerck, I; Dewulf, J; Piepers, S; Decaluwé, R; Maes, D

    2015-03-01

    One of the main characteristics of colostrum intake (CI), colostrum yield (CY), and colostrum composition (CC) in pigs is its variability. The present observational study aimed to investigate factors influencing CY and CC in 10 commercial herds. In total, 100 sows of 5 different breeds and their 1,455 live-born piglets were included. Sows' CY was estimated by the CI of their suckling piglets. Colostrum composition was analyzed by LactoScope Fourier transform infrared spectroscopy. Colostrum yield averaged 3,500 ± 110 g and the percentage of colostral fat (CF), protein, and lactose in colostrum averaged 5.39 ± 0.12, 16.49 ± 0.14, and 2.02 ± 0.05 %, respectively. The effect of sow, litter, and parturition factors on CY and CC were evaluated with a linear mixed regression model with herd included as a random factor. Sows with a gestation length (GL) of 113 d had a higher CY (4,178 ± 506 g) than sows with a GL of 114 to 115 d (3,342 ± 107 g; = 0.04). An interaction was found between the litter birth weight of suckling piglets (LW) and GL ( = 0.03). In sows with a GL of 114 to 115 d, CY increased with higher LW ( = 0.009). A shorter interval between birth and first suckling of the litter was related to a higher CY ( < 0.01). The percentage of fat in colostrums was higher in Hypor sows (6.35 ± 0.51) than in PIC (4.98 ± 0.27; = 0.001), Topigs 20 (5.05 ± 0.14; < 0.001), and Danbred (5.34 ± 0.22; < 0.001) sows. The percentage of CF was negatively associated with parity ( = 0.02) and positively associated with the number of live-born piglets ( = 0.03). The percentages of colostral protein and lactose were not significantly associated with any factor in the multivariable model. In conclusion, this study demonstrated that CY and CF are affected by different sow and litter factors. Pig producers may implement these observations in their management to maximize production or reproduction potential by optimizing CI, CY, and CC.

  3. Influences of Environmental Factors on Leaf Morphology of Chinese Jujubes

    PubMed Central

    Li, Xiaopeng; Li, Yupeng; Zhang, Zhong; Li, Xingang

    2015-01-01

    Rainfall and temperature are the primary limiting factors for optimum quality and yield of cultivated jujube (Ziziphus jujuba Mill.). Adaptation to arid and cool environments has been and remains an important goal of many jujube improvement programs. This study summarized the survey results of 116 Chinese jujube varieties grown at 33 sites in China. The objective was to identify the environmental factors that influence leaf morphology, and the implications for breeding and introduction of new jujube varieties. Jujube leaf morphological traits were evaluated for their potential relationships with mean annual temperature (MAT) and mean annual precipitation (MAP). The results showed that many leaf morphological traits had a strong linear relationship with local precipitation and temperature. Longer veins per unit area (VLA) and reduced leaf area and leaf perimeter were typical of arid areas. VLA was inversely related to MAT and MAP at the centers of origin of jujube. There was a positive relationship between leaf shape (perimeter2/area) and both MAT and MAP. These results indicated that leaf vein traits of Chinese jujubes might have resulted from their adaptation to environmental factors in the course of long-term evolution. Principal component analysis allocated the 116 jujube varieties to three different groups, differentiated on the basis of morphological and physiological leaf characteristics. Jujube varieties from the Hebei, Shandong, Henan, southern Shanxi and central Shaanxi provinces were closely related, as were varieties from northwest Shanxi and northeast Shaanxi provinces, and varieties from the Gansu and Ningxia provinces. These close relationships were partially attributed to the frequent exchanges of varieties within each group. Leaf venation characteristics might be used as reference indices for jujube variety introduction between different locations. PMID:26020971

  4. Factors influencing brown trout reproductive success in Ozark tailwater rivers

    USGS Publications Warehouse

    Pender, D.R.; Kwak, T.J.

    2002-01-01

    The reproductive success of brown trout Salmo trutta in White River, Arkansas, tailwater reaches is highly variable, resulting in the need for supplemental stocking. A better understanding of the physical and biotic factors affecting reproduction and survival would enhance the contribution of wild fish. We compared fecundity, reproductive chronology, physical habitat, water quality, trout density, food availability, diet, predation, and competitive interactions among four tailwater reaches to identify factors influencing brown trout reproductive success. The fecundity and condition factor of prespawning brown trout were significantly lower at Beaver Tailwater, a reach known for reproductive failure, than at other sites, among which no differences were found. Brown trout spawning was observed from 11 October to 23 November 1996, and juvenile emergence began on 28 February 1997. Significant among-site differences were detected for spawning and juvenile microhabitat variables, but the variables fell within or near suitable or optimal ranges reported in the literature for this species. Age-0 brown trout density differed significantly among sites, but growth and condition did not. Predation by Ozark sculpin Cottus hypselurus on trout eggs or age-0 trout of any species was not observed among the 418 stomachs examined. Ozark sculpin density and diet overlap with age-0 brown trout were highest and invertebrate food availability and water fertility were lowest at Beaver Tailwater relative to the other reaches. Our findings indicate that differences in trophic conditions occur among tailwater reaches, and a lower system productive capacity was identified at Beaver Tailwater. We suggest that management efforts include refining the multispecies trout stocking regime to improve production efficiency, enhancing flow regulation, and increasing habitat complexity to increase invertebrate and fish productivity. Such efforts may lead to improved natural reproduction and the

  5. Factors Influencing the Quality of Encapsulation in Rock Bolting

    NASA Astrophysics Data System (ADS)

    Aziz, Naj; Craig, Peter; Mirzaghorbanali, Ali; Nemcik, Jan

    2016-08-01

    Bolt installation quality is influenced by various factors, some are well known and others are less recognised. A programme of field and laboratory studies was undertaken to examine various factors of relevance to the load transfer mechanism between the bolt, resin and rock to ensure test methods truly represent field performance. Short encapsulation tests were undertaken as part of the Australian Coal Association Research Program (ACARP) funded project (C21011) with the ultimate aim of developing standard test methods for assessing bolt encapsulation with chemical resin anchor installations. The field study consisted of a series of Short Encapsulation Pull Tests (SEPT) carried out in three mines with different geological conditions to determine the most representative and practical method of SEPT. Additional field work included installation of bolts into threaded steel tubes for subsequent removal and laboratory evaluation. A series of pull tests was carried out by installing bolts in overhead rig mounted sandstone block, cast in concrete with controlled encapsulation length. Factors of importance considered included; borehole diameter, resin annulus thickness, installation time (including bolt spin to the back and "spin at back"), the effect of gloving and hole over drill. It was found that the borehole diameter had a detrimental effect on the encapsulation bonding strength. Bolt installation time of approximately 10 s constituted an acceptable time for effective bolt installation and within the resin manufacturers recommended time of 14 s. Maintaining constant length of encapsulation was paramount for obtaining consistency and repeatability of the test results. Finally, a numerical simulation study was carried out to assess the capabilities of FLAC 2D software in simulating the pull testing of rock bolts.

  6. Influences of environmental factors on leaf morphology of Chinese jujubes.

    PubMed

    Li, Xiaopeng; Li, Yupeng; Zhang, Zhong; Li, Xingang

    2015-01-01

    Rainfall and temperature are the primary limiting factors for optimum quality and yield of cultivated jujube (Ziziphus jujuba Mill.). Adaptation to arid and cool environments has been and remains an important goal of many jujube improvement programs. This study summarized the survey results of 116 Chinese jujube varieties grown at 33 sites in China. The objective was to identify the environmental factors that influence leaf morphology, and the implications for breeding and introduction of new jujube varieties. Jujube leaf morphological traits were evaluated for their potential relationships with mean annual temperature (MAT) and mean annual precipitation (MAP). The results showed that many leaf morphological traits had a strong linear relationship with local precipitation and temperature. Longer veins per unit area (VLA) and reduced leaf area and leaf perimeter were typical of arid areas. VLA was inversely related to MAT and MAP at the centers of origin of jujube. There was a positive relationship between leaf shape (perimeter2/area) and both MAT and MAP. These results indicated that leaf vein traits of Chinese jujubes might have resulted from their adaptation to environmental factors in the course of long-term evolution. Principal component analysis allocated the 116 jujube varieties to three different groups, differentiated on the basis of morphological and physiological leaf characteristics. Jujube varieties from the Hebei, Shandong, Henan, southern Shanxi and central Shaanxi provinces were closely related, as were varieties from northwest Shanxi and northeast Shaanxi provinces, and varieties from the Gansu and Ningxia provinces. These close relationships were partially attributed to the frequent exchanges of varieties within each group. Leaf venation characteristics might be used as reference indices for jujube variety introduction between different locations. PMID:26020971

  7. Factors influencing wood mobilization 1 in Minnesota streams

    USGS Publications Warehouse

    Merten, Eric; Finlay, Jacques; Johnson, Lucinda; Newman, Raymond; Stefan, Heinz; Vondracek, Bruce C.

    2010-01-01

    [1] Natural pieces of wood provide a variety of ecosystem functions in streams including habitat, organic matter retention, increased hyporheic exchange and transient storage, and enhanced hydraulic and geomorphic heterogeneity. Wood mobilization is a critical process in determining the residence time of wood. We documented the characteristics and locations of 865 natural wood pieces (>0.05 m in diameter for a portion >1 m in length) in nine streams along the north shore of Lake Superior in Minnesota. We determined the locations of the pieces again after an overbank stormflow event to determine the factors that influenced mobilization of stationary wood pieces in natural streams. Seven of 11 potential predictor variables were identified with multiple logistic regression as significant to mobilization: burial, effective depth, ratio of piece length to effective stream width (length ratio), bracing, rootwad presence, downstream force ratio, and draft ratio. The final model (P< 0.001, r2 = 0.39) indicated that wood mobilization under natural conditions is a complex function of both mechanical factors (burial, length ratio, bracing, rootwad presence, draft ratio) and hydraulic factors (effective depth, downstream force ratio). If stable pieces are a goal for stream management then features such as partial burial, low effective depth, high length relative to channel width, bracing against other objects (e.g., stream banks, trees, rocks, or larger wood pieces), and rootwads are desirable. Using the model equation from this study, stewards of natural resources can better manage in-stream wood for the benefit of stream ecosystems.

  8. Factors influencing in situ gamma-ray measurements

    NASA Astrophysics Data System (ADS)

    Loonstra, E. H.; van Egmond, F. M.

    2009-04-01

    Introduction In situ passive gamma-ray sensors are very well suitable for mapping physical soil properties. In order to make a qualitative sound soil map, high quality input parameters for calibration are required. This paper will focus on the factors that affect the output of in situ passive gamma-ray sensors, the primary source, soil, not taken into account. Factors The gamma-ray spectrum contains information of naturally occurring nuclides 40K, 238U and 232Th and man-made nuclides like 137Cs, as well as the total count rate. Factors that influence the concentration of these nuclides and the count rate can be classified in 3 categories. These are sensor design, environmental conditions and operational circumstances. Sensor design The main elements of an in situ gamma-ray sensor that influence the outcome and quality of the output are the crystal and the spectrum analysis method. Material and size of the crystal determine the energy resolution. Though widely used, NaI crystals are not the most efficient capturer of gamma radiation. Alternatives are BGO and CsI. BGO has a low peak resolution, which prohibits use in cases where man-made nuclides are subject of interest. The material is expensive and prone to temperature instability. CsI is robust compared to NaI and BGO. The density of CsI is higher than NaI, yielding better efficiency, especially for smaller crystal sizes. More volume results in higher energy efficiency. The reduction of the measured spectral information into concentration of radionuclides is mostly done using the Windows analysis method. In Windows, the activities of the nuclides are found by summing the intensities of the spectrum found in a certain interval surrounding a peak. A major flaw of the Windows method is the limited amount of spectral information that is incorporated into the analysis. Another weakness is the inherent use of ‘stripping factors' to account for contributions of radiation from nuclide A into the peak of nuclide B. This

  9. [Emission factors of polycyclic aromatic hydrocarbons (PAHs) in residential coal combustion and its influence factors].

    PubMed

    Hai, Ting-Ting; Chen, Ying-Jun; Wang, Yan; Tian, Chong-Guo; Lin, Tian

    2013-07-01

    As the emission source of polycyclic aromatic hydrocarbons (PAHs), domestic coal combustion has attracted increasing attention in China. According to the coal maturity, combustion form and stove type associated with domestic coal combustion, a large-size, full-flow dilution tunnel and fractional sampling system was employed to collect the emissions from five coals with various maturities, which were burned in the form of raw-coal-chunk (RCC)/honeycomb-coal-briquettes (HCB) in different residential stoves, and then the emission factors of PAHs (EF(PAHs)) were achieved. The results indicate that the EF(PAHs) of bituminous coal ranged from 1.1 mg x kg(-1) to 3.9 mg x kg(-1) for RCC and 2.5 mg x kg(-1) to 21. 1 mg x kg(-1) for HCB, and the anthracite EF(PAH8) were 0.2 mg x kg(-1) for RCC and 0.6 mg x kg(-1) for HCB, respectively. Among all the influence factors of emission factors of PAHs from domestic coal combustion, the maturity of coal played a major role, the range of variance reaching 1 to 2 orders of magnitude in coals with different maturity. Followed by the form of combustion (RCC/HCB), the EF(PAHs) of HCB was 2-6 times higher than that of RCC for the same geological maturity of the coal. The type of stove had little influence on EF(PAHs).

  10. Stable isotope variability in tissues of the Eurasian perch Perca fluviatilis.

    PubMed

    Vollaire, Yan; Banas, Damien; Thomas, Marielle; Roche, Hélène

    2007-11-01

    Stable isotope analysis is frequently used as a complementary method of dietary analysis, to describe trophic relationships and assess food-web structure. These studies allow a precise determination, based on the calculation of a diet-tissue fractionation factor. The fractionation factor, determined for whole organisms or specific tissues, may vary substantially in natura. In the present study, delta13C and delta15N were assessed in lipid-free tissues (spleen, liver, viscera, scales, gills, spine, white muscle, brain) and in available energy reserves (proteins, glycogen, lipids) of Eurasian perch (Perca fluviatilis) reared under controlled conditions and fed for 4 months with the same artificial diet. Some discrepancies in delta15N and delta13C data were observed among tissues, respectively up to 3.43 per thousand and 2.54 per thousand for delta15N and delta13C. The 15N signature in organs depends on their metabolic activity. Despite a significant delta13C enrichment from feed to tissues, the lipids in spine, liver and viscera exhibit a certain stability.

  11. Analysis of risk factors for the occurrence of feather pecking in laying hen growers.

    PubMed

    Huber-Eicher, B; Audigé, L

    1999-12-01

    1. Potential risk factors for the occurrence of feather pecking in laying hen growers raised under commercial conditions were investigated on Swiss farms with more than 500 rearing places. On-farm interviews were conducted on a sample of 64 flocks which represented 42.6% of all farms concerned. 2. All variables considered were dichotomised and their univariate correlation with the occurrence of feather pecking was tested for significance at P <0.20 using chi2 tests. Logistic regression with backward elimination was then used with the significant variables to identify the potentially most important factors influencing feather pecking. These variables included stocking density, light intensity, intensity of care, access to elevated perches, access to a roofed and littered outdoor area ('bad weather run'), time of access to the feeding facilities of the housing system, stocking density in the restricted area at the beginning of the rearing period, additional open feeding areas in the beginning and air quality. 3. The final model contained stocking density and access to elevated perches as significant factors (P<0.05). Flocks kept in high density (> or = 10 birds per m2) and with no access to elevated perches were 6.4 (95% Confidence interval 1.7 to 24.2) and 4.0 (95% Confidence interval 1.2 to 12.9) times more likely to be affected by feather pecking, respectively. 4. The study identified 2 risk factors for the occurrence of feather pecking in flocks of laying hen growers reared under commercial conditions. It is concluded that in order to reduce feather pecking chicks should be reared at low density and with access to elevated perches.

  12. A Phenomenological Study: The Influence of Noncognitive Factors on Academically Unprepared College Students

    ERIC Educational Resources Information Center

    Thom, Danny Moire

    2012-01-01

    This phenomenological research explored the influence of noncognitive factors in four areas: early educational factors, personal factors, affective factors, and noncognitive skill factors to understand the phenomenon of college students' academic underpreparedness. Findings related to textual categories indicated personal factors such as a…

  13. Anatomical Factors Influencing Pneumatization of the Petrous Apex

    PubMed Central

    Kim, Min-Ju; Lee, Seunghun; Choi, Hana

    2015-01-01

    Objectives Aim of the present study was to define the relationship between petrous apex pneumatization and the nearby major anatomical landmarks using temporal bone computed tomography (CT) images. Methods This retrospective, Institutional Review Board-approved study analyzed CT images of 84 patients that showed normal findings bilaterally. Pneumatization of the petrous apex was classified using two methods. Eight parameters were as follows: angle between the posterior cranial fossa and internal auditory canal, Morimitsu classification of anterior epitympanic space, distance between the carotid canal and jugular bulb, distance between the cochlear modiolus and carotid canal, distance between the tympanic segment and jugular bulb, high jugular bulb, distance between the vertical segment and jugular bulb, and distance between the lateral semicircular canals and middle cranial fossa. Results There was a significant difference in Morimitsu classification of the anterior epitympanic space between the two classification methods. Poorly pneumatic upper petrous apices were distributed uniformly in three types of Morimitsu classification, but more pneumatic upper petrous apices were found more often in anterior type. Lower petrous apex was well pneumatized regardless of the types of anterior epitympanic space, but the largest amount of pneumatization was found more frequently in the anterior type of anterior epitympanic space. Conclusion This study showed that there was no reliable anatomic marker to estimate petrous apex pneumatization and suggests that the pneumatization of the petrous apex may be an independent process from other part of the temporal bone, and may not be influenced by the nearby major anatomical structures in the temporal bone. In this study, the anterior type of anterior epitympanic space was found to be closely related to more well-pneumatized petrous apices, which implies that the anterior saccule of the saccus medius may be the main factor

  14. Influence of external factors on hair cortisol concentrations.

    PubMed

    Salaberger, Theresa; Millard, Marlon; Makarem, Samy El; Möstl, Erich; Grünberger, Viktoria; Krametter-Frötscher, Reinhild; Wittek, Thomas; Palme, Rupert

    2016-07-01

    Measuring hair cortisol has attracted interest as a long term parameter for chronic stress evaluation. However, some studies support the hypothesis that locally produced cortisol, originating from the hair follicle or skin cells, affects concentrations in the hair. In an animal model the influence of different treatments (extensive brushing, administration of a hyperemising fluid that enhances blood circulation or a synthetic glucocorticoid) on the local cortisol production of hair was evaluated. Therefore eight sheep were sheared and the area of the skin surface of the back was quartered, with three quarters being daily subjected to a certain treatment and one quarter remaining untreated. The skin areas were sheared again after three weeks and cortisol concentrations of all wool samples were determined by immunoassay. Systemic cortisol concentrations were additionally monitored with faecal samples, indicating a significant decline in concentrations of glucocorticoid metabolites between week 1 and 2 or 3, respectively. We found no significant difference in hair cortisol concentrations between fields before treatment (p=0.310). Comparing matched fields before and after treatment, we found no significant differences in wool cortisol concentrations for fields treated with hyperemising fluid as well as for the control fields (p=0.329, p=0.097). Hairs exposed to either extensive brushing or dexamethasone fluid had significantly higher immunoreactive cortisol concentrations after three weeks of treatment (p=0.016, p=0.01). We therefore advise cautious interpretation when measuring hair cortisol concentrations as a parameter for chronic stress, because external factors may have a significant influence on the results. PMID:27167500

  15. Factors influencing reproductive performance of northern bobwhite in South Florida

    USGS Publications Warehouse

    Rolland, V.; Hostetler, J.A.; Hines, T.C.; Percival, H.F.; Oli, M.K.

    2011-01-01

    Reproductive success is a critical component of individual fitness, and also an important determinant of growth rates of populations characterized by early maturity and high fecundity. We used radiotelemetry data collected during 2003-2008 to estimate reproductive parameters in a declining northern bobwhite (Colinus virginianus) population in South Florida, and to test hypotheses regarding factors influencing these parameters. The overall clutch size was 12.10 ?? 0.22, but females laid more eggs in their first clutch (12.43 ?? 0.24) than in subsequent clutches (10.19 ?? 0.53) within a nesting season. Daily nest survival was higher for first (0.966 ?? 0.003) than subsequent nests (0.936 ?? 0.011). Hatchability (proportion of laid eggs that hatched conditional upon nest survival to hatching) was 0.853 ?? 0.008, but was higher for nests incubated by females (0.873 ?? 0.009) than those incubated by males (0.798 ?? 0.018). The proportion of individuals attempting a second nest was 0.112 ?? 0.024 and 0.281 ?? 0.040 when the first nest was successful and failed, respectively. Hatchability was lower when the nesting habitat was burned the previous winter. We found no evidence that food strip density (a management practice to provide supplemental food) influenced any of the reproductive parameters. Mean summer temperature affected hatchability, nest survival, and proportion of nests incubated by males. Overall, the reproductive output in our study population was lower than that reported for most other bobwhite populations, indicating that low reproductive performance may have contributed to bobwhite population declines in our study site. These results suggest that current management practices, particularly those related to habitat and harvest management, need careful evaluation. ?? 2010 Springer-Verlag.

  16. A Southern Bald Eagle perches on a pole at KSC.

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A Southern Bald Eagle perches on top of a utility pole at Kennedy Space Center. About a dozen bald eagles live in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The Southern Bald Eagle ranges throughout Florida and along the coasts of California, Texas, Louisiana, and the south Atlantic states. Bald Eagles are listed as endangered in the U.S., except in five states where they are listed as threatened. The number of nesting pairs of the southern race once numbered several thousand; recent estimates are only 350-375. Most of the southern race nest in Florida. Eagles arrive at KSC during late summer and leave for the north in late spring. They move to nest sites in October and November and lay one to three eggs. The young fledge from February to April. The Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  17. A Southern Bald Eagle perches on a pole at KSC.

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A Southern Bald Eagle perched on top of a utility pole searches the area. About a dozen bald eagles live in the Merritt Island National Wildlife Refuge, which shares a boundary with Kennedy Space Center. The Southern Bald Eagle ranges throughout Florida and along the coasts of California, Texas, Louisiana, and the south Atlantic states. Bald Eagles are listed as endangered in the U.S., except in five states where they are listed as threatened. The number of nesting pairs of the southern race once numbered several thousand; recent estimates are only 350-375. Most of the southern race nest in Florida. Eagles arrive at KSC during late summer and leave for the north in late spring. They move to nest sites in October and November and lay one to three eggs. The young fledge from February to April. The Refuge encompasses 92,000 acres that are a habitat for more than 331 species of birds, 31 mammals, 117 fishes, and 65 amphibians and reptiles. The marshes and open water of the refuge provide wintering areas for 23 species of migratory waterfowl, as well as a year-round home for great blue herons, great egrets, wood storks, cormorants, brown pelicans and other species of marsh and shore birds, as well as a variety of insects.

  18. Factors influencing quit attempts among male daily smokers in China✩

    PubMed Central

    Zhao, Luhua; Song, Yang; Xiao, Lin; Palipudi, Krishna; Asma, Samira

    2015-01-01

    Background China has the largest population of smokers in the world, yet the quit rate is low. We used data from the 2010 Global Adult Tobacco Survey China to identify factors influencing quit attempts among male Chinese daily smokers. Methods The study sample included 3303 male daily smokers. To determine the factors that were significantly associated with making a quit attempt, we conducted logistic regression analyses. In addition, mediation anal yses were carried out to investigate how the intermediate association among demographics (age, education, urbanicity) and smoking related variables affected making a quit attempt. Results An estimated 11.0% of male daily smokers tried to quit smoking in the 12 months prior to the survey. Logistic regression analysis indicated that younger age (15–24 years), being advised to quit by a health care provider (HCP) in the past 12 months, lower cigarette cost per pack, monthly or less frequent exposure to smoking at home, and awareness of the harms of tobacco use were significantly associated with making a quit attempt. Additional mediation analyses showed that having knowledge of the harm of tobacco, exposure to smoking at home, and having been advised to quit by an HCP were mediators of making a quit attempt for other independent variables. Conclusion Evidence-based tobacco control measures such as conducting educational campaigns on the harms of tobacco use, establishing smoke-free policies at home, and integrating tobacco cessation advice into primary health care services can increase quit attempts and reduce smoking among male Chinese daily smokers. PMID:26441296

  19. Accumulation of mercury in edible macrofungi: influence of some factors.

    PubMed

    Alonso, J; Salgado, M J; García, M A; Melgar, M J

    2000-02-01

    The levels of mercury in terrestrial ecosystems are generally very low, but the strong accumulation in some species of macrofungi is an exception from this rule. Mercury contents of 41 samples of edible mushrooms fruiting bodies representing eight species (six wild and two cultivated) were determined by an anodic stripping voltammetric technique (ASV) using a gold disc as the working electrode. Wild fungi were collected in unpolluted and polluted areas in the Province of Lugo (NW Spain). Influence of some factors (ecology, species, traffic pollution, and morphological portion) and the importance of mushrooms as a dietary source of mercury have been studied. Wild saprophytic species showed higher levels (ppm DW) than mycorrhizals species, with the exception of Boletus pinicola. There were significant differences according to the species analyzed (p < 0.001), the highest average content of mercury was found in Boletus pinicola (7.37 ppm DW), and the range was 0.35-33.07 ppm DW for hymenophore and 0.18-20.30 ppm DW for the rest of the fruit body. The cultivated species accumulated lower than wild species because the mean life is shorter. The traffic pollution factor did not show significant differences, so mushrooms are not realiable bioindicators of traffic pollution by mercury. Hymenophore was always the morphological portion that contained the highest mercury levels (p < 0.05), and the mean ratio of hymenophore/rest of the fruit body was 2.13. The mercury concentrations were compared to literature data and levels set by legislation, and the contribution of mushrooms to the weekly intake of mercury per person was evaluated. The possible health risk for people is pointed out. PMID:10629276

  20. Reduction in recruitment of white bass in Lake Erie after invasion of white perch

    USGS Publications Warehouse

    Madenjian, Charles P.; Knight, Roger L.; Bur, Michael; Forney, John L.

    2000-01-01

    Recruitment to the adult population of white bass Morone chrysops in Lake Erie sharply declined during the early 1980s. To explain this phenomenon, we formulated the following four hypotheses: (1) the biological characteristics of adult spawners changed during the early 1980s, so that the ability to produce eggs decreased; (2) the decrease in phosphorus loadings to Lake Erie during the 1970s resulted in a lower abundance of crustacean zooplankton and thus in reduced survival of age-0 white bass; (3) the increase in the population of adult walleyes Stizostedion vitreum in Lake Erie during the 1970s and 1980s led to reduced survival of age-0 white bass; and (4) establishment of the white perch Morone americana population in Lake Erie during the early 1980s led to reduced survival of the early life stages of white bass. The growth, maturity, and fecundity of adults during the period 1981-1997 were compared with the same characteristics found by earlier studies. The mean length, weight, and condition factors that we calculated were higher than those reported for Lake Erie in 1927-1929 for all age groups examined, and white bass in Lake Erie matured at an earlier age during 1981-1997 than during 1927-1929. Fecundity estimates ranged from 128,897 to 1,049,207 eggs/female and were similar to estimates from other populations. Therefore, the first hypothesis was rejected. With respect to the second hypothesis, zooplankton surveys conducted during 1970 and 1983-1987 indicated that the abundance of crustacean zooplankton in Lake Erie did not change between the two time periods. However, these results were not conclusive because only a single-year survey was conducted before 1980. Based on walleye diet studies and estimates of walleye population size, walleye predation pressure on age-0 white bass in Lake Erie during 1986-1988 was just slightly higher than that during 1979-1981. Thus, such pressure can explain only a minor portion of the reduction in white bass recruitment. To

  1. Factors influencing university students' explicit and implicit sexual double standards.

    PubMed

    Sakaluk, John K; Milhausen, Robin R

    2012-01-01

    Quantitative research has resulted in inconsistent evidence for the existence of a sexual double standard, leading Crawford and Popp ( 2003 ) to issue a call for methodological innovation. The implicit association test (IAT; Greenwald, McGhee, & Schwartz, 1998 ) is a measure that may provide a means to examine the double standard without the contamination of the demand characteristics and social desirability biases that plague self-report research (Marks & Fraley, 2005 ). The purpose of this study was to examine the factors influencing explicit and implicit double standards, and to examine the relationship between these explicit and implicit double standards, and levels of socially desirable responding. One hundred and three university students completed a sexual double standard IAT, an explicit measure of the double standard, and measures of socially desirable responding. Hierarchical regression analysis indicated that levels of socially desirable responding were not related to implicit or explicit double standards. Men endorsed a stronger explicit traditional double standard than women, whereas for implicit sexual standards, men demonstrated a relatively gender-neutral evaluation and women demonstrated a strong reverse double standard. These results suggest the existence of a complex double standard, and indicate that more research of sexual attitudes should include implicit measures.

  2. Oncologist Factors That Influence Referrals to Subspecialty Palliative Care Clinics

    PubMed Central

    Schenker, Yael; Crowley-Matoka, Megan; Dohan, Daniel; Rabow, Michael W.; Smith, Cardinale B.; White, Douglas B.; Chu, Edward; Tiver, Greer A.; Einhorn, Sara; Arnold, Robert M.

    2014-01-01

    Purpose: Recent research and professional guidelines support expanded use of outpatient subspecialty palliative care in oncology, but provider referral practices vary widely. We sought to explore oncologist factors that influence referrals to outpatient palliative care. Methods: Multisite, qualitative interview study at three academic cancer centers in the United States with well-established palliative care clinics. Seventy-four medical oncologists participated in semistructured interviews between February and October 2012. The interview guide asked about experiences and decision making regarding outpatient palliative care use. A multidisciplinary team analyzed interview transcripts using constant comparative methods to inductively develop and refine themes related to palliative care referral decisions. Results: We identified three main oncologist barriers to subspecialty palliative care referrals at sites with comprehensive palliative care clinics: persistent conceptions of palliative care as an alternative philosophy of care incompatible with cancer therapy, a predominant belief that providing palliative care is an integral part of the oncologist's role, and a lack of knowledge about locally available services. Participants described their views of subspecialty palliative care as evolving in response to increasing availability of services and positive referral experiences, but emphasized that views of palliative care as valuable in addition to standard oncology care were not universally shared by oncologists. Conclusions: Improving provision of palliative care in oncology will likely require efforts beyond increasing service availability. Raising awareness of ways in which subspecialty palliative care complements standard oncology care and developing ways for oncologists and palliative care physicians to collaborate and integrate their respective skills may help. PMID:24301842

  3. Socio-economic factors influencing sustainable water supply in Botswana.

    PubMed

    Lado, C

    1997-01-01

    This study examined water use patterns in Botswana, and socioeconomic and political factors that influence sustainable water supply, and discusses water conservation and high sustainable levels of supply and demand; the market structure and its prices, costs, and subsidies; and sustainable water supplies. Data were obtained from unpublished workshop papers on integrated water resource management from seminars conducted in 1994, at the University of Botswana's Department of Environmental Science. Rainfall varied by location. Evaporation is about 4 times the average annual precipitation, which leads to continual water deficiency. Water supplies are based on ground and surface water in the ratio of 2:1. Groundwater is only partly renewable. Surface water is renewable only under the circumstance of sufficient rain and maintained storage capacity. Conservation of water is affected by the high rates of evaporation, few suitable dam sites, high temporal variability of runoff and large surface water storage capacity, the constraints of semi-arid environments, the normally critical water balance, rapid population growth and concentrations in urban areas, economic conditions, and the general increase in living conditions. The governments need to strengthen control over non-market water use and to provide sufficient incentives for efficient water use. Water prices should increase in order to reflect the total economic value, regardless of the political consequences. There are needs to protect water catchment areas and to clarify ownership of water resources. Control of demand should include prioritizing water consumption.

  4. Factors that Influence the Effectiveness of Sanitation Programs.

    PubMed

    Fernandez-Haddad, Marilu; Ingram, Maia

    2015-01-01

    Local governments in both Mexico and the U.S. spend considerable money on public services, which do not always bring the expected results. For instance, a large part of the public budget is destined to solve social and health problems, such as public sanitation. Government has attacked the problem by providing public sanitation infrastructure (such as garbage and recycling receptacles) and by using social ad campaigns. However, these efforts do not always affect the habits of residents and bring the desired changes in city sanitation. This article presents a case study that used a participatory method to address an innovative city sanitation effort: The Clean City Program in Puebla, Mexico. This program adopted social marketing techniques, a discipline born in the 70s when the principles and practices developed to sell products and services started to be applied to sell ideas, attitudes, or behaviors. Social marketing programs have been adopted by governments to change attitudes and behavior in areas such as public services. The article first describes the context and strategies of the program, which included the use of the promotora model to engage community members. The researchers then make use of qualitative data gathered throughout program planning and implementation to evaluate the impact of the social marketing programs and its effectiveness. The article analyzes social, educational, economic, demographic, and cultural factors that influence the effectiveness of sanitation programs and presents recommendations for strategies to engage community members in community sanitation programs. PMID:26389106

  5. Factors influencing radiation therapy student clinical placement satisfaction

    SciTech Connect

    Bridge, Pete; Carmichael, Mary-Ann

    2014-02-15

    Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning.

  6. Factors influencing the density of aerobic granular sludge.

    PubMed

    Winkler, M-K H; Kleerebezem, R; Strous, M; Chandran, K; van Loosdrecht, M C M

    2013-08-01

    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 staining. The volume fraction occupied by precipitates was determined by computed tomography scanning. PHREEQC was used to estimate potential formation of precipitates to determine a density of the inorganic fraction. Densities of bacteria were investigated by Percoll density centrifugation. The volume fractions were then coupled with the corresponding densities and the total density of a granule was calculated. The sensitivity of the density of the entire granule on the corresponding settling velocity was evaluated by changing the volume fractions of precipitates or bacteria in a settling model. Results from granules originating from a Nereda reactor for simultaneous phosphate COD and nitrogen removal revealed that phosphate-accumulating organisms (PAOs) had a higher density than glycogen-accumulating organisms leading to significantly higher settling velocities for PAO-dominated granules explaining earlier observations of the segregation of the granular sludge bed inside reactors. The model showed that a small increase in the volume fraction of precipitates (1-5 %) strongly increased the granular density and thereby the settling velocity. For nitritation-anammox granular sludge, mainly granular diameter and not density differences are causing a segregation of the biomass in the bed. PMID:23064481

  7. Factors that Influence Body Image Representations of Black Muslim Women

    PubMed Central

    2008-01-01

    Research on the body image perceptions of black women is limited. Although previous body image studies have explored the intersection between race and gender, the influence of religion has been neglected. Guided by a grounded theory framework, the focus of this investigation, conducted in Upstate New York, USA, was to examine the role of race and religion in the body image perceptions of 22 African-American Sunni Muslim women. Analysis of individual interviews revealed that, in contrast to using standard medical guidelines, participants’ views about their bodies were largely based on positive images of an earlier body size/shape, social and family expectations and contexts, cultural norms and values, and spirituality and religious beliefs. Although the body image perceptions of black Muslim women were similar to those expressed in previous body image studies with black women, participants expressed the importance of highlighting the spiritual versus physical self by adhering to religious guidelines regarding proper dress and appearance. These findings suggest that religion, race, and gender are all important factors to be considered when conducting body image studies with black women. PMID:18384923

  8. Factors that Influence the Effectiveness of Sanitation Programs

    PubMed Central

    Fernandez-Haddad, Marilu; Ingram, Maia

    2015-01-01

    Local governments in both Mexico and the U.S. spend considerable money on public services, which do not always bring the expected results. For instance, a large part of the public budget is destined to solve social and health problems, such as public sanitation. Government has attacked the problem by providing public sanitation infrastructure (such as garbage and recycling receptacles) and by using social ad campaigns. However, these efforts do not always affect the habits of residents and bring the desired changes in city sanitation. This article presents a case study that used a participatory method to address an innovative city sanitation effort: The Clean City Program in Puebla, Mexico. This program adopted social marketing techniques, a discipline born in the 70s when the principles and practices developed to sell products and services started to be applied to sell ideas, attitudes, or behaviors. Social marketing programs have been adopted by governments to change attitudes and behavior in areas such as public services. The article first describes the context and strategies of the program, which included the use of the promotora model to engage community members. The researchers then make use of qualitative data gathered throughout program planning and implementation to evaluate the impact of the social marketing programs and its effectiveness. The article analyzes social, educational, economic, demographic, and cultural factors that influence the effectiveness of sanitation programs and presents recommendations for strategies to engage community members in community sanitation programs. PMID:26389106

  9. Determination of specificity influencing residues for key transcription factor families

    PubMed Central

    Patel, Ronak Y.; Garde, Christian; D.Stormo, Gary

    2015-01-01

    Transcription factors (TFs) are major modulators of transcription and subsequent cellular processes. The binding of TFs to specific regulatory elements is governed by their specificity. Considering the gap between known TFs sequence and specificity, specificity prediction frameworks are highly desired. Key inputs to such frameworks are protein residues that modulate the specificity of TF under consideration. Simple measures like mutual information (MI) to delineate specificity influencing residues (SIRs) from alignment fail due to structural constraints imposed by the three-dimensional structure of protein. Structural restraints on the evolution of the amino-acid sequence lead to identification of false SIRs. In this manuscript we extended three methods (Direct Information, PSICOV and adjusted mutual information) that have been used to disentangle spurious indirect protein residue-residue contacts from direct contacts, to identify SIRs from joint alignments of amino-acids and specificity. We predicted SIRs forhomeodomain (HD), helix-loop-helix, LacI and GntR families of TFs using these methods and compared to MI. Using various measures, we show that the performance of these three methods is comparable but better than MI. Implication of these methods in specificity prediction framework is discussed. The methods are implemented as an R package and available along with the alignments at stormo.wustl.edu/SpecPred. PMID:26753103

  10. Environmental factors influencing diatom communities in Antarctic cryoconite holes

    NASA Astrophysics Data System (ADS)

    Stanish, L. F.; Bagshaw, E. A.; McKnight, D. M.; Fountain, A. G.; Tranter, M.

    2013-12-01

    Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of Antarctica, these holes are often capped by an ice lid that prevents the exchange of material and gases with the surrounding atmosphere and aquatic environment. Diatoms have been documented in cryoconite holes, and recent findings suggest that these habitats may harbour a distinctive diatom flora compared to the surrounding aquatic environments. In this study, we examined diatom community composition in cryoconite holes and environmental correlates across three glaciers in Taylor Valley, Antarctica. The diatom communities were dominated by two genera, Muelleria and Diadesmis, both of which had high viability and could have been seeded from the surrounding ephemeral streams. The location of the cryoconite hole within the valley was a key determinant of community composition. A diatom species richness gradient was observed that corresponded to distance inland from the coast and co-varied with species richness in streams within the same lake basin. Cryoconite holes that were adjacent to streams with higher diversity displayed greater species richness. However, physical factors, such as the ability to withstand freeze-thaw conditions and to colonize coarse sediments, acted as additional selective filters and influenced diatom diversity, viability and community composition.

  11. Self-reported factors influencing exercise adherence in overweight women.

    PubMed

    Gillett, P A

    1988-01-01

    The purpose of this study was to determine the effect of intensity-controlled, graded dance exercise and selected components of behavior modification on exercise adherence in overweight middle-aged women. Thirty-eight moderately overweight women, aged 35 to 58, participated in a 16 1/2 week dance exercise program. Participants were randomly assigned to an experimental group (n = 20) that received intensity-controlled, graded exercise and individual and group reinforcement, or to a control group (n = 18) that exercised at a moderate intensity typical of commercial fitness classes and received no special reinforcement. Before exercise training began and at the completion of 16 1/2 weeks, a structured, open-ended interview was conducted. Ninety-four percent of the women in both groups adhered to the program, an exceptionally high adherence rate for this population. Eight participant-identified factors seemed to have influenced exercise adherence: group homogeneity, carpooling and social networks, pleasurable feelings associated with increased energy and fitness, leader with a health-related background, time limitation of exercise program, commitment to an established goal, desire to change body image, and desire to change health status and improve physical health.

  12. Factors Influencing Phosphorous Cycling in Biogeochemical 'Hot Spots'

    NASA Astrophysics Data System (ADS)

    Saia, S. M.; Walter, M. T.; Buda, A. R.; Carrick, H. J.; Regan, J. M.

    2015-12-01

    Anthropogenic alteration of the phosphorus (P) cycle has led to subsequent soil and water quality issues. For example, P build up in soils due to historic fertilizer application may become biologically available and exacerbate eutrophication and anoxia in nearby water bodies. In the humid Northeastern United States, storm runoff transports P and also stimulates biogeochemical processes, these locations are termed biogeochemical 'hot spots'. Many studies have looked at nitrogen and carbon cycling in biogeochemical hot spots but few have focused on P. We hypothesize the periodic wetting and drying of biogeochemical hot spots promotes a combination of abiotic and biotic processes that influence the mobility of P. To test this hypothesis, we took monthly soil samples (5 cm deep) from May to October in forest, pasture, and cropped land near Ithaca, NY. In-situ measurements taken with each sample included volumetric soil moisture and soil temperature. We also analyzed samples for 'runoff generated' phosphate, nitrate, and sulfate (from 0.01 M CaCl2 extraction), Fe(II), percent organic matter, pH, as well as oxalate extractable and total P, Al, and Fe. We used linear mixed effects models to test how runoff generated phosphate concentrations vary with soil moisture and whether other environmental factors strengthen/weaken this relationship. The knowledge gained from this study will improve our understanding of P cycling in biogeochemical hot spots and can be used to improve the effectiveness of agricultural management practices in the Northeastern United States.

  13. Factors influencing bird foraging preferences among conspecific fruit trees

    USGS Publications Warehouse

    Foster, M.S.

    1990-01-01

    The rates at which birds visit fruiting individuals of Allophylus edulis (Sapindaceae) differ substantially among trees. Such avian feeding preferences are well-known, but usually involve fruits and trees of different species. Factors controlling avian preferences for particular trees in a population of conspecifics are generally undocumented. To address this issue, I attempted to correlate rates at which individual birds and species fed in trees of Allophylus with 27 fruit or plant characteristics. Birds that swallow fruits whole were considered separately from those that feed in other ways. Plant characters were selected on the basis of their potential influence on feeding efficiency or predation risk, assuming that birds would select feeding trees so as to maximize the net rate of energy or nutrient intake and to minimize predation. Correlations were found between feeding visits by some groups of birds and percent water in the pulp, milligrams of mineral ash in the pulp, and crop size. No character was correlated with feeding visits by all groups of birds in both years of the study. The correlations with water and mineral ash are unexplained and may be artifacts. The correlation with crop size may represent a tactic to minimize predation.

  14. Factors influencing adoption of manure separation technology in The Netherlands.

    PubMed

    Gebrezgabher, Solomie A; Meuwissen, Miranda P M; Kruseman, Gideon; Lakner, Dora; Oude Lansink, Alfons G J M

    2015-03-01

    Manure separation technologies are essential for sustainable livestock operations in areas with high livestock density as these technologies result in better utilization of manure and reduced environmental impact. Technologies for manure separation have been well researched and are ready for use. Their use, however, has been limited to the Netherlands. This paper investigates the role of farm and farmer characteristics and farmers' attitudes toward technology-specific attributes in influencing the likelihood of the adoption of mechanical manure separation technology. The analysis used survey data collected from 111 Dutch dairy farmers in 2009. The results showed that the age and education level of the farmer and farm size are important variables explaining the likelihood of adoption. In addition to farm and farmer characteristics, farmers' attitudes toward the different attributes of manure separation technology significantly affect the likelihood of adoption. The study generates useful information for policy makers, technology developers and distributors in identifying the factors that impact decision-making behaviors of farmers. PMID:25460418

  15. Influence of Life Style Factors on Barrett's Oesophagus.

    PubMed

    Horna Strand, A; Franzén, T

    2014-01-01

    Background. Since the incidence of adenocarcinoma of the oesophagus is rising, the prognosis is poor, and surveillance programs are expensive and mostly cost ineffective, there is a need to increase the knowledge of risk factors in Barrett's oesophagus and oesophageal cancer in order to be able to give attention to medical prevention and/or surveillance programs. Aim. To study if there is a correlation between the development of Barrett's oesophagus and GOR (gastro oesophageal reflux), family history of GOR, and life style factors, such as alcohol, smoking habits, and mental stress. Methods. Fifty-five consecutively selected patients with Barrett's oesophagus (BO) examined at Linköping University Hospital's Oesophageal Laboratory were matched by sex, age, and duration of reflux symptoms with 55 GOR patients without Barrett's oesophagus at the Oesophageal Laboratory. The medical charts in respective groups were examined for comparison of life style factors, mental stress, medication, duration of gastroesophageal acid reflux at 24 hr-pH-metry, and incidence of antireflux surgery and of adenocarcinoma of the oesophagus (ACO). Also, potential gender differences and diagnosis of ACO were studied. Results. Mean percentage reflux time on 24 hr-pH-metry was higher for the Barrett's oesophagus group, 18% for women and 17% for men compared to 4% for women and 4% for men in the control group (P < 0.05). Family history of GOR was more frequent in Barrett's oesophagus patients (62%) than in the control group (35%) (P < 0.05). Male patients with Barrett's oesophagus had medical therapy for their GOR symptoms to a higher extent (38%) than male controls (65%) (P < 0.05). No difference was found in the number of tobacco users or former tobacco users between Barrett's oesophagus patients and controls. Barrett's oesophagus patients had the same level of alcohol consumption and the same average BMI as the control subjects. Female patients with Barrett's oesophagus rated

  16. Factors influencing recovery and restoration following a chemical incident.

    PubMed

    Peña-Fernández, A; Wyke, S; Brooke, N; Duarte-Davidson, R

    2014-11-01

    Chemicals are an important part of our society. A wide range of chemicals are discharged into the environment every day from residential, commercial and industrial sources. Many of these discharges do not pose a threat to public health or the environment. However, global events have shown that chemical incidents or accidents can have severe consequences on human health, the environment and society. It is important that appropriate tools and technical guidance are available to ensure that a robust and efficient approach to developing a remediation strategy is adopted. The purpose of remediation is to protect human health from future exposure and to return the affected area back to normal as soon as possible. There are a range of recovery options (techniques or methods for remediation) that are applicable to a broad range of chemicals and incidents. Recovery options should be evaluated according to their appropriateness and efficacy for removing contaminants from the environment; however economic drivers and social and political considerations often influence decision makers on which remedial actions are implemented during the recovery phase of a chemical incident. To date, there is limited information in the literature on remediation strategies and recovery options that have been implemented following a chemical incident, or how successful they have been. Additional factors that can affect the approach taken for recovery are not well assessed or understood by decision makers involved in the remediation and restoration of the environment following a chemical incident. The identification of this gap has led to the development of the UK Recovery Handbook for Chemical Incidents to provide a framework for choosing an effective recovery strategy. A compendium of practical evidence-based recovery options (techniques or methods for remediation) for inhabited areas, food production systems and water environments has also been developed and is included in the chemical

  17. Evidence of hypoxic foraging forays by yellow perch (Perca flavescens) and potential consequences for prey consumption

    USGS Publications Warehouse

    Roberts, James J.; Grecay, Paul A.; Ludsin, Stuart A.; Pothoven, Steve A.; Vanderploeg, Henry A.; Höök, Tomas O.

    2012-01-01

    Previous studies in a variety of ecosystems have shown that ecologically and economically important benthic and bentho-pelagic fishes avoid hypoxic (−1) habitats by moving vertically or horizontally to more oxygenated areas. While avoidance of hypoxic conditions generally leads to a complete shift away from preferred benthic prey, some individual fish continue to consume benthic prey items in spite of bottom hypoxia, suggesting complex habitat utilisation and foraging patterns. For example, Lake Erie yellow perch (Perca flavescens) continue to consume benthic prey, despite being displaced vertically and horizontally by hypolimnetic hypoxia. We hypothesised that hypolimnetic hypoxia can negatively affect yellow perch by altering their distribution and inducing energetically expensive foraging behaviour. To test this hypothesis, we used drifting hydroacoustics and trawl sampling to quantify water column distribution, sub-daily vertical movement and foraging behaviour of yellow perch within hypoxic and normoxic habitats of Lake Erie’s central basin during August-September 2007. We also investigated the effects of rapid changes in ambient oxygen conditions on yellow perch consumption potential by exposing yellow perch to various static and fluctuating oxygen conditions in a controlled laboratory experiment. Our results indicate that, while yellow perch in general avoid hypoxic conditions, some individuals undertake foraging forays into hypoxic habitats where they experience greater fluctuations in abiotic conditions (pressure, temperature and oxygen concentration) than at normoxic sites. However, laboratory results suggest short-term exposure to low oxygen conditions did not negatively impact consumption potential of yellow perch. Detailed understanding of sub-daily individual behaviours may be crucial for determining interactive individual- and ecosystem-level effects of stressors such as hypoxia.

  18. Molecular and pharmacological properties of GABA-rho subunits from white perch retina.

    PubMed

    Qian, H; Dowling, J E; Ripps, H

    1998-11-01

    Five gamma-aminobutyric acid (GABA)-rho subunits were cloned from a white perch retinal cDNA library and expressed in Xenopus oocytes. The deduced amino acid sequences indicated that all are highly homologous to the GABA-rho subunits cloned from mammalian retinas; two clones (perch-rho 1A and perch-rho 1B) were in the rho 1 family, two (perch-rho 2A and perch-rho 2B) were in the rho 2 family, and one clone has been tentatively identified as a perch-rho 3 subunit. When expressed in Xenopus oocytes, all but one of the subunits (rho 3) formed functional homooligomeric receptors. However, the receptors expressed by each of the GABA-rho subunits displayed unique response properties that distinguished one from the other. For example, receptors formed by perch-rho 1B subunits were more sensitive to GABA than the receptors formed by other GABA-rho subunits, the dose-response curves for the various receptors revealed different Hill coefficients, and there were differences in the kinetics of the GABA-induced currents. In addition, the GABA-mediated current-voltage curve for rho 2 receptors was approximately linear, whereas the responses from rho 1 receptors showed outward rectification. A further division in the properties of the GABA-rho subunits was revealed in their responses to imidazole-4-acetic acid (I4AA); the drug behaved as an antagonist on A-type rho receptors and a partial agonist on the B-type rho receptors. These results suggest that there is a large diversity of GABAC receptors in the vertebrate retina, probably formed by homooligomeric and heterooligomeric combinations of GABA rho subunits, that exhibit different functional properties. PMID:9805275

  19. Parental Factors that Influence the Career Development of College-Bound African American High School Seniors

    ERIC Educational Resources Information Center

    Bostic, Shenice S.

    2010-01-01

    Parents have been identified as being the most influential factor upon their children career development. There are various factors that influence the career development of individuals from different ethnic backgrounds. The purpose of the study was to identify parental factors that influence the career development of college-bound African American…

  20. A Survey of the Influencing Factors for International Academic Mobility of Chinese University Students

    ERIC Educational Resources Information Center

    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…

  1. 21 CFR 1404.860 - What factors may influence the debarring official's decision?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false What factors may influence the debarring official... GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Debarment § 1404.860 What factors may influence the debarring official's decision? This section lists the mitigating and aggravating factors that the...

  2. 22 CFR 1006.860 - What factors may influence the debarring official's decision?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true What factors may influence the debarring... DEBARMENT AND SUSPENSION (NONPROCUREMENT) Debarment § 1006.860 What factors may influence the debarring official's decision? This section lists the mitigating and aggravating factors that the debarring...

  3. 22 CFR 208.860 - What factors may influence the debarring official's decision?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false What factors may influence the debarring... GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Debarment § 208.860 What factors may influence the debarring official's decision? This section lists the mitigating and aggravating factors that the...

  4. 22 CFR 1508.860 - What factors may influence the debarring official's decision?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true What factors may influence the debarring... GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Debarment § 1508.860 What factors may influence the debarring official's decision? This section lists the mitigating and aggravating factors that the...

  5. Factors influencing particulate lipid production in the East Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Gašparović, B.; Frka, S.; Koch, B. P.; Zhu, Z. Y.; Bracher, A.; Lechtenfeld, O. J.; Neogi, S. B.; Lara, R. J.; Kattner, G.

    2014-07-01

    Extensive analyses of particulate lipids and lipid classes were conducted to gain insight into lipid production and related factors along the biogeochemical provinces of the Eastern Atlantic Ocean. Data are supported by particulate organic carbon (POC), chlorophyll a (Chl a), phaeopigments, Chl a concentrations and carbon content of eukaryotic micro-, nano- and picophytoplankton, including cell abundances for the latter two and for cyanobacteria and prokaryotic heterotrophs. We focused on the productive ocean surface (2 m depth and deep Chl a maximum (DCM). Samples from the deep ocean provided information about the relative reactivity and preservation potential of particular lipid classes. Surface and DCM particulate lipid concentrations (3.5-29.4 μg L-1) were higher than in samples from deep waters (3.2-9.3 μg L-1) where an increased contribution to the POC pool was observed. The highest lipid concentrations were measured in high latitude temperate waters and in the North Atlantic Tropical Gyral Province (13-25°N). Factors responsible for the enhanced lipid synthesis in the eastern Atlantic appeared to be phytoplankton size (micro, nano, pico) and the low nutrient status with microphytoplankton having the most expressed influence in the surface and eukaryotic nano- and picophytoplankton in the DCM layer. Higher lipid to Chl a ratios suggest enhanced lipid biosynthesis in the nutrient poorer regions. The various lipid classes pointed to possible mechanisms of phytoplankton adaptation to the nutritional conditions. Thus, it is likely that adaptation comprises the replacement of membrane phospholipids by non-phosphorus containing glycolipids under low phosphorus conditions. The qualitative and quantitative lipid compositions revealed that phospholipids were the most degradable lipids, and their occurrence decreased with increasing depth. In contrast, wax esters, possibly originating from zooplankton, survived downward transport probably due to the fast sinking

  6. Which factors influence psychiatric diagnosing in substance abuse treatment?

    PubMed Central

    2013-01-01

    Background The importance of diagnosing and treating co-occurring psychiatric disorders among substance abusers in treatment has received much attention. The aim of this study was to investigate to which extent co-occurring psychiatric disorders are diagnosed in a clinical population of substance abusers, and which factors (including the use of MINI-Plus) that influence the diagnosing of co-occurring psychiatric disorders. Methods Patients (N = 275) who received inpatient substance use treatment in five different units in Northern Norway participated in the study. The patients’ clinicians gave information on diagnoses given during the stay in the units, and whether a systematic diagnostic tool was used for the diagnosing (MINI-Plus). Predictors of independent co-occurring psychiatric disorders were examined utilizing hierarchical regression analysis. Results One third of the patients were given an independent psychiatric diagnosis. Less than half of the patients were assessed using a diagnostic tool. The main predictor of diagnosing of independent psychiatric disorders was the use of the diagnostic tool MINI-Plus. Younger patients and patients that used less alcohol, were given independent psychiatric diagnoses more frequently. Conclusions The number of co-occurring independent psychiatric diagnoses was lower compared to other studies using standardized diagnostic tools. The low number of patients assessed by such a tool, and the strong relationship between the use of such a tool and the diagnosing of co-occurring psychiatric disorders, suggest that the implementation of standardized diagnostic tools should be addressed in the units. Generally, patients suffering from substance use disorders should be systematically screened for other psychiatric disorders, in order to improve their treatment and health. PMID:23742628

  7. Factors influencing uptake of familial long QT syndrome genetic testing.

    PubMed

    Burns, Charlotte; McGaughran, Julie; Davis, Andrew; Semsarian, Christopher; Ingles, Jodie

    2016-02-01

    Ongoing challenges of clinical assessment of long QT syndrome (LQTS) highlight the importance of genetic testing in the diagnosis of asymptomatic at-risk family members. Effective access, uptake, and communication of genetic testing are critical for comprehensive cascade family screening and prevention of disease complications such as sudden cardiac death. The aim of this study was to describe factors influencing uptake of LQTS genetic testing, including those relating to access and family communication. We show those who access genetic testing are overrepresented by the socioeconomically advantaged, and that although overall family communication is good, there are some important barriers to be addressed. There were 75 participants (aged 18 years or more, with a clinical and/or genetic diagnosis of LQTS; response rate 71%) who completed a survey including a number of validated scales; demographics; and questions about access, uptake, and communication. Mean age of participants was 46 ± 16 years, 20 (27%) were males and 60 (80%) had genetic testing with a causative gene mutation in 42 (70%). Overall uptake of cascade testing within families was 60% after 4 years from proband genetic diagnosis. All participants reported at least one first-degree relative had been informed of their risk, whereas six (10%) reported at least one first-degree relative had not been informed. Those who were anxious or depressed were more likely to perceive barriers to communicating. Genetic testing is a key aspect of care in LQTS families and intervention strategies that aim to improve equity in access and facilitate effective family communication are needed.

  8. Factors influencing uptake of familial long QT syndrome genetic testing.

    PubMed

    Burns, Charlotte; McGaughran, Julie; Davis, Andrew; Semsarian, Christopher; Ingles, Jodie

    2016-02-01

    Ongoing challenges of clinical assessment of long QT syndrome (LQTS) highlight the importance of genetic testing in the diagnosis of asymptomatic at-risk family members. Effective access, uptake, and communication of genetic testing are critical for comprehensive cascade family screening and prevention of disease complications such as sudden cardiac death. The aim of this study was to describe factors influencing uptake of LQTS genetic testing, including those relating to access and family communication. We show those who access genetic testing are overrepresented by the socioeconomically advantaged, and that although overall family communication is good, there are some important barriers to be addressed. There were 75 participants (aged 18 years or more, with a clinical and/or genetic diagnosis of LQTS; response rate 71%) who completed a survey including a number of validated scales; demographics; and questions about access, uptake, and communication. Mean age of participants was 46 ± 16 years, 20 (27%) were males and 60 (80%) had genetic testing with a causative gene mutation in 42 (70%). Overall uptake of cascade testing within families was 60% after 4 years from proband genetic diagnosis. All participants reported at least one first-degree relative had been informed of their risk, whereas six (10%) reported at least one first-degree relative had not been informed. Those who were anxious or depressed were more likely to perceive barriers to communicating. Genetic testing is a key aspect of care in LQTS families and intervention strategies that aim to improve equity in access and facilitate effective family communication are needed. PMID:26544151

  9. Factors influencing the latency of simple reaction time

    PubMed Central

    Woods, David L.; Wyma, John M.; Yund, E. William; Herron, Timothy J.; Reed, Bruce

    2015-01-01

    Simple reaction time (SRT), the minimal time needed to respond to a stimulus, is a basic measure of processing speed. SRTs were first measured by Francis Galton in the 19th century, who reported visual SRT latencies below 190 ms in young subjects. However, recent large-scale studies have reported substantially increased SRT latencies that differ markedly in different laboratories, in part due to timing delays introduced by the computer hardware and software used for SRT measurement. We developed a calibrated and temporally precise SRT test to analyze the factors that influence SRT latencies in a paradigm where visual stimuli were presented to the left or right hemifield at varying stimulus onset asynchronies (SOAs). Experiment 1 examined a community sample of 1469 subjects ranging in age from 18 to 65. Mean SRT latencies were short (231, 213 ms when corrected for hardware delays) and increased significantly with age (0.55 ms/year), but were unaffected by sex or education. As in previous studies, SRTs were prolonged at shorter SOAs and were slightly faster for stimuli presented in the visual field contralateral to the responding hand. Stimulus detection time (SDT) was estimated by subtracting movement initiation time, measured in a speeded finger tapping test, from SRTs. SDT latencies averaged 131 ms and were unaffected by age. Experiment 2 tested 189 subjects ranging in age from 18 to 82 years in a different laboratory using a larger range of SOAs. Both SRTs and SDTs were slightly prolonged (by 7 ms). SRT latencies increased with age while SDT latencies remained stable. Precise computer-based measurements of SRT latencies show that processing speed is as fast in contemporary populations as in the Victorian era, and that age-related increases in SRT latencies are due primarily to slowed motor output. PMID:25859198

  10. Factors influencing undergraduates' self-evaluation of numerical competence

    NASA Astrophysics Data System (ADS)

    Tariq, Vicki N.; Durrani, Naureen

    2012-04-01

    This empirical study explores factors influencing undergraduates' self-evaluation of their numerical competence, using data from an online survey completed by 566 undergraduates from a diversity of academic disciplines, across all four faculties at a post-1992 UK university. Analysis of the data, which included correlation and multiple regression analyses, revealed that undergraduates exhibiting greater confidence in their mathematical and numeracy skills, as evidenced by their higher self-evaluation scores and their higher scores on the confidence sub-scale contributing to the measurement of attitude, possess more cohesive, rather than fragmented, conceptions of mathematics, and display more positive attitudes towards mathematics/numeracy. They also exhibit lower levels of mathematics anxiety. Students exhibiting greater confidence also tended to be those who were relatively young (i.e. 18-29 years), whose degree programmes provided them with opportunities to practise and further develop their numeracy skills, and who possessed higher pre-university mathematics qualifications. The multiple regression analysis revealed two positive predictors (overall attitude towards mathematics/numeracy and possession of a higher pre-university mathematics qualification) and five negative predictors (mathematics anxiety, lack of opportunity to practise/develop numeracy skills, being a more mature student, being enrolled in Health and Social Care compared with Science and Technology, and possessing no formal mathematics/numeracy qualification compared with a General Certificate of Secondary Education or equivalent qualification) accounted for approximately 64% of the variation in students' perceptions of their numerical competence. Although the results initially suggested that male students were significantly more confident than females, one compounding variable was almost certainly the students' highest pre-university mathematics or numeracy qualification, since a higher

  11. Factors influencing immunologic response to hepatitis B vaccine in adults

    PubMed Central

    Yang, Shigui; Tian, Guo; Cui, Yuanxia; Ding, Cheng; Deng, Min; Yu, Chengbo; Xu, Kaijin; Ren, Jingjing; Yao, Jun; Li, Yiping; Cao, Qing; Chen, Ping; Xie, Tiansheng; Wang, Chencheng; Wang, Bing; Mao, Chen; Ruan, Bing; Jiang, Tian’an; Li, Lanjuan

    2016-01-01

    Hepatitis B was still a worldwide health problem. This study aimed to conducted a systematic review and meta-analysis to assess a more precise estimation of factors that influence the response to hepatitis B vaccine in adults. Our included studies examined seroprotection rates close to the end of vaccination schedules in healthy adult populations. This meta-analysis including 21053 adults in 37 articles showed that a significantly decreased response to hepatitis B vaccine appeared in adults (age ≥ 40) (RR:1.86, 95% CI:1.55–2.23), male adults (RR:1.40, 95% CI:1.22–1.61), BMI ≥ 25 adults (RR:1.56, 95% CI:1.12–2.17), smoker (RR:1.53, 95% CI:1.21–1.93), and adults with concomitant disease (RR:1.39, 95% CI:1.04–1.86). Meanwhile, we further found a decreased response to hepatitis B vaccine appeared in adults (age ≥ 30) (RR:1.77, 95% CI:1.48–2.10), and adults (age ≥ 60) (RR:1.30, 95% CI:1.01–1.68). However, there were no difference in response to hepatitis B vaccine both in alcoholic (RR:0.90, 95% CI:0.64–1.26) and 0-1-12 vs. 0-1-6 vaccination schedule (RR:1.39, 95% CI:0.41–4.67). Pooling of these studies recommended the sooner the better for adult hepatitis B vaccine strategy. More vaccine doses, supplemental/additional strengthening immunity should be emphasized on the susceptible population of increasing aged, male, BMI ≥ 25, smoking and concomitant disease. The conventional 0-1-6 vaccination schedule could be still worth to be recommended. PMID:27324884

  12. Factors influencing methionine toxicity in young bobwhite quail

    USGS Publications Warehouse

    Serafin, J.A.

    1981-01-01

    Young Bobwhite quail (Colinus virginianus) were fed low and adequate protein purified diets with and without excess methionine to evaluate factors affecting methionine toxicity. Growth of quail fed an adequate protein (27%) diet, without supplemental glycine, was depressed by 1.75% and 2.25% excess methionine. Supplemental glycine (.3%) alleviated growth depression caused by 2.25% excess methionine. Quail fed 1.75% and 2.25% excess methionine developed signs of toxicity characterized by weakness, a lowered, outstretched neck when moving, and ataxia. In addition, quail would fall on their sides when disturbed and spin with their heads retracted. These conditions were transient in nature. Growth of quail fed a low protein (18.9%) diet was depressed by 1% and 1.5% excess methionine and DL-homocystine. Quail fed 1% and 1.5% excess methionine in this diet also developed signs of toxicity, the incidence of which was greater and the duration longer than occurred with quail fed adequate protein. Supplementing a low protein (20.15%) diet with .3% or .6% glycine or threonine or a combination of these amino acids did not alleviate growth depression caused by 1.5% excess methionine; however, 2% and 3% supplemental glycine were somewhat effective. Supplements of glycine (2%, 3%) and threonine (1%) completely reversed growth depression from 1% excess methionine but did not influence growth of controls, indicating that both amino acids counteract methionine toxicity. Both glycine and threonine alone improved growth by about the same extent in diets with 1% or 1.5% excess methionine; however, these amino acids alleviated less than 30% of the growth depression resulting from 1.5% excess methionine. The effectiveness of glycine in alleviating methionine toxicity in a low protein diet was decreased, and hemoglobin levels were depressed with 1.5% excess methionine compared to less amounts.

  13. Race influences warfarin dose changes associated with genetic factors.

    PubMed

    Limdi, Nita A; Brown, Todd M; Yan, Qi; Thigpen, Jonathan L; Shendre, Aditi; Liu, Nianjun; Hill, Charles E; Arnett, Donna K; Beasley, T Mark

    2015-07-23

    Warfarin dosing algorithms adjust for race, assigning a fixed effect size to each predictor, thereby attenuating the differential effect by race. Attenuation likely occurs in both race groups but may be more pronounced in the less-represented race group. Therefore, we evaluated whether the effect of clinical (age, body surface area [BSA], chronic kidney disease [CKD], and amiodarone use) and genetic factors (CYP2C9*2, *3, *5, *6, *11, rs12777823, VKORC1, and CYP4F2) on warfarin dose differs by race using regression analyses among 1357 patients enrolled in a prospective cohort study and compared predictive ability of race-combined vs race-stratified models. Differential effect of predictors by race was assessed using predictor-race interactions in race-combined analyses. Warfarin dose was influenced by age, BSA, CKD, amiodarone use, and CYP2C9*3 and VKORC1 variants in both races, by CYP2C9*2 and CYP4F2 variants in European Americans, and by rs12777823 in African Americans. CYP2C9*2 was associated with a lower dose only among European Americans (20.6% vs 3.0%, P < .001) and rs12777823 only among African Americans (12.3% vs 2.3%, P = .006). Although VKORC1 was associated with dose decrease in both races, the proportional decrease was higher among European Americans (28.9% vs 19.9%, P = .003) compared with African Americans. Race-stratified analysis improved dose prediction in both race groups compared with race-combined analysis. We demonstrate that the effect of predictors on warfarin dose differs by race, which may explain divergent findings reported by recent warfarin pharmacogenetic trials. We recommend that warfarin dosing algorithms should be stratified by race rather than adjusted for race.

  14. Factors potentially influencing academic performance among medical students

    PubMed Central

    Al Shawwa, Lana; Abulaban, Ahmad A; Abulaban, Abdulrhman A; Merdad, Anas; Baghlaf, Sara; Algethami, Ahmed; Abu-shanab, Joullanar; Balkhoyor, Abdulrahman

    2015-01-01

    Background Studies are needed to examine predictors of success in medical school. The aim of this work is to explore factors that potentially influence excellence of medical students. Methods The study was conducted in the Medical Faculty of King Abdulaziz University during October 2012. A self-administered questionnaire was used. Medical students with a grade point average (GPA) ≥4.5 (out of 5) were included and compared to randomly selected medical students with a GPA <4.5, who were available at the time of the study. Results A total of 359 undergraduate students participated in the study. 50.4% of the sample was students with a GPA ≥4.5. No statistically significant difference regarding the time spent on outings and social events was found. However, 60.7% of high GPA students spend less than 2 hours on social networking per day as compared to 42.6% of the lower GPA students (P<0.01). In addition, 79% of high GPA students prefer to study alone (P=0.02), 68.0% required silence and no interruptions during studying time (P=0.013), and 47% revise their material at least once before an exam (P=0.02). Conclusion Excellent medical students have many different characteristics. For example, they do not use social networking for prolonged periods of time, and they have strong motivation and study enjoyment. Further studies are needed to examine whether these differences have a real impact on GPA or not. PMID:25674033

  15. A review of factors influencing litter size in Irish sows

    PubMed Central

    2007-01-01

    Many factors influence litter size. These include genetics, gilt management, lactation length, parity distribution, disease, stress and boar fertility. In the past 20 years, litter size in Irish sows has increased by only one pig. Born alive figures now average at 11.2 pigs per litter. In this regard, Ireland is falling behind our European competitors who have made significant advances over this time. Denmark, for example, has an average figure of 12.7 pigs born alive per litter and France an average of 12.5. The single area that could be improved immediately is sow feeding. It is important that sows are fed correctly throughout pregnancy. If over-fed during pregnancy, sows will have depressed appetite during lactation. If underfed in pregnancy, sows will be too thin at farrowing. The correct way to feed a pregnant sow is to match her feed allocation to her requirement for maintenance, body growth and growth of her developing foetuses. During lactation, sows should be given as much feed as they can eat to prevent excessive loss of body condition. Liquid-feed curves should be such that lactating sows are provided with a minimum mean daily feed supply of 6.2 kg. A small proportion of sows will eat more and this could be given as supplementary dry feed. Where dry feeding is practised in the farrowing house, it is difficult to hand-feed sows to match their appetite. Ideally ad libitum wet/dry feeders should be used. From weaning to service, sows should once again be fed ad libitum. If liquid feeding, this means giving at least 60 MJ DE (digestible energy) per day during this period. If dry feeding, at least 4 kg of lactation diet should be fed daily. The effort spent perfecting sow feeding management on units should yield high dividends in the form of increased pigs born alive per litter. PMID:21851695

  16. Who Is Who: An Anomalous Predator-Prey Role Exchange between Cyprinids and Perch.

    PubMed

    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

    Piscivory in cyprinids (Cyprinidae) is extremely rare. Specifically, common bream (Abramis brama) and common carp (Cyprinus carpio) are zooplanktivorous fish in deep lentic waters. Nevertheless, we observed predation by these two cyprinids under natural conditions in the Vír Reservoir, Czech Republic. We conducted diet analysis for cyprinids caught by trawling and gillnets and the large amount of young-of-the-year (YOY) perch (Perca fluviatilis), with sizes of 37-52 mm standard length, were found in their digestive tracts. In 2010, a large amount of YOY perch caused a significant decrease in Daphnia spp. size and abundance in the reservoir. Hence, a food deficit was induced for the cyprinids, apparent also from the poor nutritional condition of common bream which was much worse than the condition of those in similar reservoirs. Common carp and common bream shifted to forced piscivory, and they utilized the YOY perch as an alternative food source. In contrast, smaller species, such as roach (Rutilus rutilus) and bleak (Alburnus alburnus), widely utilized planktonic cyanobacteria. In the following year, YOY perch occurred in significantly lower numbers and conversely, Daphnia spp. size and abundance were significantly higher. The forced piscivory was not observed. Our results indicate a switch to forced piscivory by cyprinids, which was caused by a shortage of their natural food source. Moreover, this phenomenon presents an effective mechanism for reduction in the numbers of YOY perch, ensuring the stability of the ecosystem.

  17. Communication in the third dimension: song perch height of rivals affects singing response in nightingales.

    PubMed

    Sprau, Philipp; Roth, Tobias; Naguib, Marc; Amrhein, Valentin

    2012-01-01

    Many animals use long-range signals to compete over mates and resources. Optimal transmission can be achieved by choosing efficient signals, or by choosing adequate signalling perches and song posts. High signalling perches benefit sound transmission and reception, but may be more risky due to exposure to airborne predators. Perch height could thus reflect male quality, with individuals signalling at higher perches appearing as more threatening to rivals. Using playbacks on nightingales (Luscinia megarhynchos), we simulated rivals singing at the same height as residents, or singing three metres higher. Surprisingly, residents increased song output stronger, and, varying with future pairing success, overlapped more songs of the playback when rivals were singing at the same height than when they were singing higher. Other than expected, rivals singing at the same height may thus be experienced as more threatening than rivals singing at higher perches. Our study provides new evidence that territorial animals integrate information on signalling height and thus on vertical cues in their assessment of rivals. PMID:22448215

  18. Who Is Who: An Anomalous Predator-Prey Role Exchange between Cyprinids and Perch

    PubMed Central

    Blabolil, Petr; Jůza, Tomáš; Vašek, Mojmír; Ricard, Daniel; Matěna, Josef; Frouzová, Jaroslava; Kubečka, Jan; Říha, Milan

    2016-01-01

    Piscivory in cyprinids (Cyprinidae) is extremely rare. Specifically, common bream (Abramis brama) and common carp (Cyprinus carpio) are zooplanktivorous fish in deep lentic waters. Nevertheless, we observed predation by these two cyprinids under natural conditions in the Vír Reservoir, Czech Republic. We conducted diet analysis for cyprinids caught by trawling and gillnets and the large amount of young-of-the-year (YOY) perch (Perca fluviatilis), with sizes of 37–52 mm standard length, were found in their digestive tracts. In 2010, a large amount of YOY perch caused a significant decrease in Daphnia spp. size and abundance in the reservoir. Hence, a food deficit was induced for the cyprinids, apparent also from the poor nutritional condition of common bream which was much worse than the condition of those in similar reservoirs. Common carp and common bream shifted to forced piscivory, and they utilized the YOY perch as an alternative food source. In contrast, smaller species, such as roach (Rutilus rutilus) and bleak (Alburnus alburnus), widely utilized planktonic cyanobacteria. In the following year, YOY perch occurred in significantly lower numbers and conversely, Daphnia spp. size and abundance were significantly higher. The forced piscivory was not observed. Our results indicate a switch to forced piscivory by cyprinids, which was caused by a shortage of their natural food source. Moreover, this phenomenon presents an effective mechanism for reduction in the numbers of YOY perch, ensuring the stability of the ecosystem. PMID:27276078

  19. Who Is Who: An Anomalous Predator-Prey Role Exchange between Cyprinids and Perch.

    PubMed

    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

    Piscivory in cyprinids (Cyprinidae) is extremely rare. Specifically, common bream (Abramis brama) and common carp (Cyprinus carpio) are zooplanktivorous fish in deep lentic waters. Nevertheless, we observed predation by these two cyprinids under natural conditions in the Vír Reservoir, Czech Republic. We conducted diet analysis for cyprinids caught by trawling and gillnets and the large amount of young-of-the-year (YOY) perch (Perca fluviatilis), with sizes of 37-52 mm standard length, were found in their digestive tracts. In 2010, a large amount of YOY perch caused a significant decrease in Daphnia spp. size and abundance in the reservoir. Hence, a food deficit was induced for the cyprinids, apparent also from the poor nutritional condition of common bream which was much worse than the condition of those in similar reservoirs. Common carp and common bream shifted to forced piscivory, and they utilized the YOY perch as an alternative food source. In contrast, smaller species, such as roach (Rutilus rutilus) and bleak (Alburnus alburnus), widely utilized planktonic cyanobacteria. In the following year, YOY perch occurred in significantly lower numbers and conversely, Daphnia spp. size and abundance were significantly higher. The forced piscivory was not observed. Our results indicate a switch to forced piscivory by cyprinids, which was caused by a shortage of their natural food source. Moreover, this phenomenon presents an effective mechanism for reduction in the numbers of YOY perch, ensuring the stability of the ecosystem. PMID:27276078

  20. FACTORS INFLUENCING TOTAL DIETARY EXPOSURE OF YOUNG CHILDREN

    EPA Science Inventory

    A deterministic model was developed to identify critical input parameters to assess dietary intake of young children. The model was used as a framework for understanding important factors in data collection and analysis. Factors incorporated included transfer efficiencies of pest...

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

    PubMed

    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.

  2. Factors influencing exemplary science teachers' levels of computer use

    NASA Astrophysics Data System (ADS)

    Hakverdi, Meral

    This study examines exemplary science teachers' use of technology in science instruction, factors influencing their level of computer use, their level of knowledge/skills in using specific computer applications for science instruction, their use of computer-related applications/tools during their instruction, and their students' use of computer applications/tools in or for their science class. After a relevant review of the literature certain variables were selected for analysis. These variables included personal self-efficacy in teaching with computers, outcome expectancy, pupil-control ideology, level of computer use, age, gender, teaching experience, personal computer use, professional computer use and science teachers' level of knowledge/skills in using specific computer applications for science instruction. The sample for this study includes middle and high school science teachers who received the Presidential Award for Excellence in Science Teaching Award (sponsored by the White House and the National Science Foundation) between the years 1997 and 2003 from all 50 states and U.S. territories. Award-winning science teachers were contacted about the survey via e-mail or letter with an enclosed return envelope. Of the 334 award-winning science teachers, usable responses were received from 92 science teachers, which made a response rate of 27.5%. Analysis of the survey responses indicated that exemplary science teachers have a variety of knowledge/skills in using computer related applications/tools. The most commonly used computer applications/tools are information retrieval via the Internet, presentation tools, online communication, digital cameras, and data collection probes. Results of the study revealed that students' use of technology in their science classroom is highly correlated with the frequency of their science teachers' use of computer applications/tools. The results of the multiple regression analysis revealed that personal self-efficacy related to

  3. Factors That Influence the Size of Tropical Cyclones

    NASA Astrophysics Data System (ADS)

    Wang, Shuai; Toumi, Ralf; Czaja, Arnaud; Van Kan, Adrian

    2015-04-01

    Tropical cyclone (TC) size is an important feature setting the extent of coastal flooding, the size of storm surge and area threatened by landfall. The importance of TC size is demonstrated comparing Hurricanes Sandy in 2012 and Bret in 1999. As a Saffir-Simpson Hurricane Scale category-3 hurricane, the radius of gale-force wind of Hurricane Sandy exceeded 800 km prior to landfall, and the storm caused catastrophic storm surge into the New Jersey and New York coastlines, and damage up to an estimated total of 50 billion. Hurricane Bret, on the other hand, was a more intense category-4 hurricane with a radius of gale-force wind of only 140 km. Although Bret's intensity is considerable, damage was reported to be relatively light, totalling an estimated 60 million. The difference impacts are mainly caused by the difference in size. Despite the fact that a wide range of observed TC sizes has been recognised, the underlying factors that control both individual storm size and the climatological size variation remain mysterious. Here an idealized full-physics numerical cyclone model and a modified hurricane steady-state model (λ model) for TC wind profile are used to investigate the influence of environmental temperature and initial vortex properties on TC size. In the simulation we find that a sea surface temperature increase, a temperature decrease in the upper troposphere, a large or strong initial vortex can lead to the extension of TC size. The numerical model simulations show a Gaussian distribution with width, λ, of the moist entropy in the boundary layer. The width, λ, has good linear relationship with the size changes caused by different factors. With regards to TC size and intensity, we find that, unlike the intensity prediction based on the maximum potential intensity theory, it seems that there is no upper limit for TC size providing there is sufficient latent heat flux. The increase of TC size at the steady stage also causes a slight drop in intensity. In

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

    PubMed

    Athiê, S; Dias, M M

    2016-02-01

    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. PMID:26909627

  5. The effect of perches in cages during pullet rearing and egg laying on hen performance, foot health, and plumage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to determine if perch availability during all or part of the life cycle of caged Hy-Line W-36 chickens affected egg traits, foot health, and feather condition. Using a 2 x 2 factorial arrangement, treatment 1 represented control chickens which never had access to perches during the...

  6. 77 FR 65838 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-31

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea Subarea of the Bering Sea and Aleutian... directed fishing for Pacific ocean perch in the Bering Sea subarea of the Bering Sea and Aleutian Islands management area. This action is necessary to fully use the 2012 total allowable catch of Pacific ocean...

  7. 75 FR 42337 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-21

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors Participating in the Rockfish Limited...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by catcher/processors...). This action is necessary to prevent exceeding the 2010 total allowable catch (TAC) of Pacific...

  8. 75 FR 68726 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea Subarea of the Bering Sea and Aleutian... directed fishing for Pacific ocean perch in the Bering Sea subarea of the Bering Sea and Aleutian Islands management area. This action is necessary to fully use the 2010 total allowable catch of Pacific ocean...

  9. 76 FR 39793 - Fisheries of the Exclusive Economic Zone Off Alaska; Northern Rockfish, Pacific Ocean Perch, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... Economic Zone Off Alaska; Northern Rockfish, Pacific Ocean Perch, and Pelagic Shelf Rockfish for Catcher... northern rockfish, Pacific ocean perch, and pelagic shelf rockfish for catcher vessels participating in the... necessary to prevent exceeding the 2011 total allowable catch (TAC) of northern rockfish, Pacific...

  10. 75 FR 38936 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-07

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels Participating in the Rockfish Entry Level...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by trawl catcher vessels...). This action is necessary to prevent exceeding the 2010 directed fishing allowance of Pacific...

  11. 75 FR 38938 - Fisheries of the Exclusive Economic Zone Off Alaska; Northern Rockfish, Pacific Ocean Perch, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-07

    ... Economic Zone Off Alaska; Northern Rockfish, Pacific Ocean Perch, and Pelagic Shelf Rockfish for Catcher... northern rockfish, Pacific ocean perch, and pelagic shelf rockfish for catcher vessels participating in the... necessary to prevent exceeding the 2010 total allowable catch (TAC) of northern rockfish, Pacific...

  12. 75 FR 41999 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-20

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels Participating in the Rockfish Entry Level...; modification of closure. SUMMARY: NMFS is reopening directed fishing for Pacific ocean perch by trawl catcher... Alaska (GOA). This action is necessary to fully use the 2010 directed fishing allowance of Pacific...

  13. 76 FR 43934 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-22

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher/Processors Participating in the Rockfish Limited...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by catcher/processors...). This action is necessary to prevent exceeding the 2011 total allowable catch (TAC) of Pacific...

  14. 75 FR 69361 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-12

    ... groundfish in the BSAI (75 FR 11778, March 12, 2010). The harvest specification for the 2010 Pacific ocean... Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea Subarea of the Bering Sea and Aleutian... available data and finds that the ITAC for Pacific ocean perch in the Bering Sea subarea needs to...

  15. 76 FR 39790 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... Economic Zone Off Alaska; Pacific Ocean Perch for Catcher Vessels Participating in the Rockfish Entry Level...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific ocean perch by trawl catcher vessels...). This action is necessary ] to prevent exceeding the 2011 directed fishing allowance of Pacific...

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

    USGS Publications Warehouse

    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.

  17. Population biology of yellow perch in southern Lake Michigan, 1971-79

    USGS Publications Warehouse

    Wells, LaRue; Jorgenson, Sherrell C.

    1983-01-01

    This study was based mainly on gill-net collections of yellow perch (Perca flavescens) made during July and August 1971-79, in southern Lake Michigan at Grand Haven, Saugatuck, South Haven, Benton Harbor, and New Buffalo, Michigan; Michigan City and Gary, Indiana; Waukegan, Illinois; and Milwaukee, Wisconsin. Abundance of yellow perch was above the 1971-79 average in 1971 and 1972, below average in 1979, and about average or in doubt in the other years. Abundance during 1976-79 was greatest at Saugatuck and decreased more or less progressively from Saugatuck southward and around the southern end of the lake. The geographical differences in abundance were attributable partly to differences in fishing mortality. Average lengths of fish caught were greatest at Saugatuck, and generally greater in Michigan waters than in other areas; they were greater for females than for males. Fish sampled ranged in age from I to IX, but 88% of the males and 81% of the females were of ages II-V. Older perch were generally more common in State of Michigan waters, particularly at Saugatuck, than elsewhere. Females grew faster than males after the second year of life. Average lengths of males and females at the end of 3 years were 197 and 214 mm, respectively, in Michigan waters and 186 and 195 mm in Indiana-Illinois (few perch were caught in Wisconsin). The relation of weight (W) to length (L) for combined sexes was W = 2.6761(10-6) x L3.2644. Perch in southeastern Lake Michigan spawned mainly from late May to mid June. Virtually all males were mature in their second year, but some females not until their fourth year. Perch 174 to 355 mm long contained 9, 300 to 136, 000 eggs. Approximate mortalities of males and females in Michigan waters were 52% and 48%, respectively; rates were higher in Indiana-Illinois.

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

    PubMed

    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.

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

    PubMed

    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. PMID:26480912

  20. Age, growth, and production of the yellow perch, Perca flavescens (Mitchill), of Saginaw Bay

    USGS Publications Warehouse

    Hile, Ralph; Jobes, Frank W.

    1941-01-01

    Ages were determined and individual growth histories computed from the examination and measurement of scales from 820 yellow perch collected in 1929 and 1930. Calculated lengths greater than 101 millimeters were computed on the assumption (supported by empirical data) that the ratio of body length to scale length is constant. Lengths below 101 millimeters were determined with the aid of an empirical curve of the body-scale relationship of small fish. Yellow perch of age-groups III and IV (in the fourth and fifth years of life) made up the bulk of the collection (78 per cent). Females grew slightly more rapidly than males, but members of both sexes attained the legal length of 8 1/2 inches during the fourth year of life, just as they were entering on the period of most rapid growth in weight. The greatest growth in weight of both sexes occurred in the sixth year of life. In the combined samples of the two years the females exceeded the males in abundance in the ratio, 296:100. The weight of the Saginaw Bay yellow perch was found to increase as the 3.117 power of the length. The relative length of the tail decreased with increase in the length of the fish. The Saginaw Bay yellow perch is now far less abundant than it was in the early years of the fishery. The average annual production of 548,000 pounds over the period, 1917-1938, was only 28 per cent of the earlier (1891-1916) "normal" annual production of 1,961,000 pounds. A detailed analysis of statistical data available for more recent years made possible a description of annual fluctuations in the abundance and production of yellow perch and in the intensity of the yellow perch fishery in Saginaw Bay over the period, 1929-1938.

  1. Factors Influencing Early Lexical Acquisition: Lexical Orientation and Phonological Composition.

    ERIC Educational Resources Information Center

    Leonard, Laurence B.; And Others

    1981-01-01

    Children exhibiting a referential orientation seem more likely to acquire new object names than nonreferentially oriented children. Also, children's selection of words may be influenced by the phonological structure of the words. (Author/RH)

  2. Breastfeeding in America: a history of influencing factors.

    PubMed

    Thulier, Diane

    2009-02-01

    The author explores the history of breastfeeding in America. Popular belief is that medicine, science, and the formula industry have had the most impact on women's decisions to bottle versus breastfeed. What cannot be overlooked are other areas of influence. Cultural practices, including the beliefs of colonial Americans, the increased social value of children in the 20th century, and the emergence of a middle class, have influenced maternal decision making. The first and second waves of feminism affected women's choices. Politics and religion have had multiple and varied influences. It is this author's position that culture, gender, politics, and religion, as well as medicine, science, and industry, have combined to affect feeding choices. All of these influences, as well as others, both unforeseen and unpredictable, will continue to affect the future of breastfeeding in our society.

  3. Breastfeeding in America: a history of influencing factors.

    PubMed

    Thulier, Diane

    2009-02-01

    The author explores the history of breastfeeding in America. Popular belief is that medicine, science, and the formula industry have had the most impact on women's decisions to bottle versus breastfeed. What cannot be overlooked are other areas of influence. Cultural practices, including the beliefs of colonial Americans, the increased social value of children in the 20th century, and the emergence of a middle class, have influenced maternal decision making. The first and second waves of feminism affected women's choices. Politics and religion have had multiple and varied influences. It is this author's position that culture, gender, politics, and religion, as well as medicine, science, and industry, have combined to affect feeding choices. All of these influences, as well as others, both unforeseen and unpredictable, will continue to affect the future of breastfeeding in our society. PMID:19196856

  4. Rearing without early access to perches impairs the spatial skills of laying hens.

    PubMed

    Gunnarsson; Yngvesson; Keeling; Forkman

    2000-04-01

    The effect of rearing with and without perches on the spatial ability of domestic hens (Gallus gallus domesticus) was investigated. No access or late access to perches during rearing has been shown to increase the later prevalence of floor eggs and cloacal cannibalism in loose-housed laying hens. This may be explained by either the birds reared without perches have difficulty using perches due to low muscle strength, lack of motor skills, and inability to keep balance, or they have impaired spatial skills necessary for moving around in three-dimensional space. These alternative explanations are not mutually exclusive.Thirty, day-old chicks were randomly allocated into two equal groups and reared in litter pens, one with access to perches (P+) and one without (P-). At 8 weeks of age, all birds were given access to perches, and by 15 weeks, all birds were using perches for roosting at night. At 16 weeks, 10 birds from each group were tested in pens where food was presented on a wire mesh tier 40 cm above the ground (T40). Three consecutive tests, with increasing difficulty for the bird to reach the food, were then performed. Firstly, the food was presented at 80 cm above the ground but with the tier at 40 cm still present; secondly, food was presented on the tier at 80 cm; and then, finally, with the food on a 160 cm high tier with the tier at 80 cm still present. All birds were food deprived for 15 h before each test and the time from the bird entering the pen until reaching the food was recorded. There was no difference in the time to reach the food between P+ and P- birds in the T40 test. But as the difficulty of the task increased, the difference between the P+ and P- birds became significant, with the P- birds taking a longer time to reach the food or not reaching it at all. Since there was no difference between P+ and P- in the T40 test, it seems reasonable to suppose that the later differences did not depend on differences in physical ability. Therefore, the

  5. 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

    USGS Publications Warehouse

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

    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 ?? = 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. ?? 2009 Elsevier B.V.

  6. Liver transplantation for hepatocellular carcinoma - factors influencing outcome and disease-free survival

    PubMed Central

    Fahrner, René; Dondorf, Felix; Ardelt, Michael; Dittmar, Yves; Settmacher, Utz; Rauchfuß, Falk

    2015-01-01

    Hepatocellular carcinoma is one of the leading causes of cancer-related death worldwide. Liver transplantation can be a curative treatment in selected patients. However, there are several factors that influence disease-free survival after transplantation. This review addresses the pre-, intra- and postoperative factors that influence the risk of tumor recurrence after liver transplantation. PMID:26576092

  7. What Matters Most: Factors Influencing the University Application Choice Decisions of Korean International Students and Parents

    ERIC Educational Resources Information Center

    Parslow, Breanna

    2014-01-01

    The purpose of this study is to determine factors influencing Korean parents' and students' university application choice decisions in three international schools in the Republic of Korea (South). Institutional and individual factors that influenced Korean students' university application choice decisions and their parents' university application…

  8. Factors Influencing New Entrant Dairy Farmer's Decision-Making Process around Technology Adoption

    ERIC Educational Resources Information Center

    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…

  9. Alteration of Influencing Factors of E-Learning Continued Intention for Different Degrees of Online Participation

    ERIC Educational Resources Information Center

    Chang, Chi-Cheng; Liang, Chaoyun; Shu, Kuen-Ming; Chiu, Yi-Chun

    2015-01-01

    The purpose of the present study was to investigate the variation of influencing factors of e-learning continuance intention for different degrees of participation and to examine moderating effects of degrees of participation on influencing factors of e-learning continuance intention. Participants included 670 learners from an adult professional…

  10. 29 CFR 98.860 - What factors may influence the debarring official's decision?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... your present responsibility. In making a debarment decision, the debarring official may consider the... 29 Labor 1 2010-07-01 2010-07-01 true What factors may influence the debarring official's decision... (NONPROCUREMENT) Debarment § 98.860 What factors may influence the debarring official's decision? This...

  11. 41 CFR 105-68.860 - What factors may influence the debarring official's decision?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... responsibility. In making a debarment decision, the debarring official may consider the following factors: (a... influence the debarring official's decision? 105-68.860 Section 105-68.860 Public Contracts and Property...) Debarment § 105-68.860 What factors may influence the debarring official's decision? This section lists...

  12. Overcoming Misconceptions via Analogical Reasoning: Factors Influencing Understanding in a Teaching Experiment.

    ERIC Educational Resources Information Center

    Brown, David E.; Clement, John

    In most research that investigates factors influencing the success of analogies in instruction, an underlying assumption is that students have little or no knowledge of the target situation. It is interesting to ask what factors influence the success of analogies when students believe they understand the target situation. If this understanding is…

  13. Factors Influencing Nontraditional Vocational Education Enrollments: A Literature Review. Research and Development Series No. 150.

    ERIC Educational Resources Information Center

    Vetter, Louise; And Others

    The literature on factors influencing nontraditional enrollment choices may be approached in this order: background information on the labor force and vocational education, factors influencing nontraditional enrollments, and strategies for increasing nontraditional enrollments. Despite an increase of women in nontraditional occupations, research…

  14. 21 CFR 1404.880 - What factors may influence the debarring official during reconsideration?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false What factors may influence the debarring official during reconsideration? 1404.880 Section 1404.880 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Debarment § 1404.880 What factors may influence...

  15. Shaping an Identity: Factors Influencing the Achievement of Newly Married, Gifted Young Women.

    ERIC Educational Resources Information Center

    Neumeister, Kristie L. Speirs

    2002-01-01

    This study examined factors influencing professional achievement of three newly married, gifted women recently graduated from college. Major findings include that participants attributed a significant part of their identities to their status as high achievers. Identify was also influenced by foundational influences, personality characteristics,…

  16. Factors Influencing the Career Planning and Development of University Students in Jordan

    ERIC Educational Resources Information Center

    Khasawneh, Samer

    2010-01-01

    The purpose of this study was to translate and validate an Arabic version of the career influence inventory for use in Jordan. The study also investigated perceptions of university students of the influential factors that have influenced their career planning and development. The validated career influence inventory was administered to 558…

  17. Factors that Influence Policy Decisions in Literacy: Perspectives of Key Policy Informants

    ERIC Educational Resources Information Center

    Mraz, Maryann E.

    2004-01-01

    The purpose of this study was to examine the perspectives of key policy informants on the factors that they believed influence policy decisions in literacy education. Participants were selected because they had significantly influenced, or had attempted to influence, policy decisions in literacy at either the national or state level.…

  18. Effects of long-term changes in the benthic community on yellow perch in Saginaw Bay, Lake Huron

    USGS Publications Warehouse

    Schaeffer, Jeffrey S.; Diana, James S.; Haas, Robert C.

    2000-01-01

    Abundance, mortality, age and growth, food habits, and energetics of a yellow perch Perca flavescens population were investigated in eutrophic Saginaw Bay, Lake Huron during May to October, 1986 to 1988, and compared population characteristics with historical data from times when eutrophic conditions were less severe. During 1986 to 1988, yellow perch were abundant, but grew slowly and experienced high natural mortality. A size threshold was present at 150 to 180 mm beyond which few individuals survived, and sex ratios became biased toward males. An energetic model suggested that yellow perch were food limited; as they increased in size they spent a greater proportion of the growing season near maintenance ration. Low feeding rates were a consequence of subsistence on small chironomid larvae. Piscivory provided little energetic relief. Historical data suggested that availability of large benthic prey such as nymphs of the burrowing mayfly Hexagenia was important to yellow perch. Yellow perch formerly consumed Hexagenia, but mayflies were extirpated from Saginaw Bay during 1953 to 1965, and never recovered. When Hexagenia was present, yellow perch growth was moderate to fast depending on population size, size thresholds were not present, and yellow perch reached large size and older age despite moderate to high fishing mortality. Decreases in yellow perch growth rates during 1952 to 1955 coincided with extirpation of Hexagenia. Fast growth of yellow perch did occur after Hexagenia became extirpated, but only when fishing mortality was high, population size was small, and some large benthic invertebrates remained. Eutrophication of Saginaw Bay appeared to affect yellow perch by changing species composition and reducing size structure of the benthic community.

  19. Factors Influencing Satisfaction for Family Practice Residency Faculty.

    ERIC Educational Resources Information Center

    Kay, Lawrence E.; D'Amico, Frank

    1999-01-01

    A survey of 383 faculty in family medical-residency programs explored perceptions of 60 professional, scheduling, compensation, and regional factors as they related to overall job satisfaction and career plans, and 59 factors related to the initial decision to enter academic family medicine. Results indicate high levels of satisfaction, feeling…

  20. Teacher Professionalization: Motivational Factors and the Influence of Age

    ERIC Educational Resources Information Center

    Hildebrandt, Susan A.; Eom, Minhee

    2011-01-01

    This study examines motivational factors of teachers who have achieved a national standard of professionalization. Data were collected from National Board certified teachers in the United States (N = 453) using a two-part, web-based survey. Exploratory factor analysis found five motivators: improved teaching, financial gain, collaborative…