Influence of abiotic stress signals on secondary metabolites in plants

PubMed Central

Ramakrishna, Akula; Ravishankar, Gokare Aswathanarayana

2011-01-01

Plant secondary metabolites are unique sources for pharmaceuticals, food additives, flavors, and industrially important biochemicals. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Secondary metabolites play a major role in the adaptation of plants to the environment and in overcoming stress conditions. Environmental factors viz. temperature, humidity, light intensity, the supply of water, minerals, and CO2 influence the growth of a plant and secondary metabolite production. Drought, high salinity, and freezing temperatures are environmental conditions that cause adverse effects on the growth of plants and the productivity of crops. Plant cell culture technologies have been effective tools for both studying and producing plant secondary metabolites under in vitro conditions and for plant improvement. This brief review summarizes the influence of different abiotic factors include salt, drought, light, heavy metals, frost etc. on secondary metabolites in plants. The focus of the present review is the influence of abiotic factors on secondary metabolite production and some of important plant pharmaceuticals. Also, we describe the results of in vitro cultures and production of some important secondary metabolites obtained in our laboratory. PMID:22041989

Abiotic and biotic factors influencing nanoflagellate abundance and distribution in three different seasons in PRE, South China Sea

NASA Astrophysics Data System (ADS)

Zhang, Xia; Shi, Zhen; Huang, Xiaoping; Li, Xiangfu

2017-07-01

Spatial distribution characteristics of two nanoflagellate groups, together with physico-chemical and biological factors, were studied in three seasons in the Pearl River Estuary (PRE), South China Sea. Nanoflagellates were more abundant in warm periods than that in winter. The average abundance in the three observations (spring, summer and winter) was as follow: 1.28 ± 1.17, 0.88 ± 1.02 and 0.28 ± 0.23 × 103 cells ml-1 of heterotrophic nanoflagellate (HNF), and 1.26 ± 0.85, 0.89 ± 0.77 and 0.65 ± 0.52 × 103 cells ml-1 of pigmented nanoflagellate (PNF). In our three studied seasons, NF density was generally higher in the inner estuary and decreasing to the lowest in the outer estuary. Our results suggested that PNF classes were more sensitive than HNF groups to freshwater discharge. The proportion of PNF gradually increased from spring (49.7%) to winter (67.7%), with the river flow was accordingly decreasing. Moreover, spatial distribution pattern in three seasons showed the response of PNF populations to freshwater input was similar to phytoplankton assemblages in the PRE. Total bacterial and live bacterial abundance (measured by LIVE/DEAD kit) were associated with both two NF components, which implied that NF was a potential predator controlling the bulk abundance of bacteria and proportion of active cells. These results revealed the seasonal and spatial variations of NF abundance in diverse conditions in the PRE and how their response to different ecological processes.

Environment Is Life (EIL): a new local structure to study the influence of abiotic factors on agro-systems functional behavior

NASA Astrophysics Data System (ADS)

Longdoz, Bernard; Leemans, Vincent; Heinesch, Bernard; Delaplace, Pierre; Dumont, Benjamin; Jacques, Philippe

2017-04-01

, to simulate the biogeochemical cycles of an outdoor agro-system plots. The objectives of the model runs will be to translate for natural conditions (real agro-system), the impact of the studied perturbation, with possibilities of divergences in terms of intensity and timing compared to the Ecotron situations Finally, the structure is completed with an eddy covariance tower site named Lonzée installed in a traditional European temperate agro-system plot and presently part of the ICOS labeling process. The Lonzee site is a cropland (cultivated for more than 75 years) with a 4-year rotation: sugar beet (Beta vulgaris L.), winter wheat (Triticum aestivum L.), potato (Solanum tuberosum L.), winter wheat. The experimental device collect some data similar to those obtained in the Ecotron chambers and will give the opportunity to (i) quantify the actual and real the influence of abiotic factors on ecosystemic services and (ii) validate the model used for the spatio-temporal extrapolation of the Ecotron results.

The shifting influence of abiotic drivers during landslide succession in Puerto Rico

Treesearch

L. R. Walker; A. B. Shiels; P. J. Bellingham; A. D. Sparrow; N. Fetcher; F. H. Landau; D. J. Lodge

2013-01-01

Summary 1. Abiotic variables are critical drivers of succession in most primary seres, but how their influence on biota changes over time is rarely examined. Landslides provide good model systems for examining abiotic influences because they are spatially and temporally heterogeneous habitats with distinct abiotic and biotic gradients and post-landslide erosion. 2. In...

The Effect of Different Oceanic Abiotic Factors on Prokaryotic Body Sizes

NASA Astrophysics Data System (ADS)

Pidathala, S.; Bellon, M.; Heim, N.; Payne, J.

2016-12-01

We are studying the impact of abiotic factors in the Pacific and Atlantic on prokaryotic body sizes and genome sizes because we are interested in the manner in which abiotic factors influence genome sizes independent of their influence on body sizes. Some research has been done in the past on marine bacterial evolution, including data collection on marine ecology in relation to bacterial body sizes (Straza 2009). We are using the abiotic factors: temperature, salinity, and pH to compare the biovolumes/genome sizes of different phyla by using R. We made 9 scatter plots to model these relationships. Regardless of the phyla or the ocean, we found that there is no relation between pH, temperature, and body size, with several exceptions: Deinococcus. thermus has an indirect relationship with size in respect to temperature; size only correlates to temperature for phyla that are thermophiles. We also found that bacteria like D. thermus and Thermotogae are taxa only found in higher temperatures. Additionally, almost all phyla have genome sizes restricted by certain pH levels:, Proteobacteria only reach genomes with acidity levels greater than 6. In terms of salinity levels, certain bacteria are only found within a small range, and others, like Proteobacteria, can only reach genomes at low salinity levels. Finally, Proteobacteria have large genome sizes between 30 and 40 °, and Crenarchaeota have constant genome sizes in higher temperatures. Conclusively, we discovered that these abiotic factors generally do not affect body size, with the exception of D. thermus' indirect relationship to temperature due to its small biovolume in high temperatures. However, we determined that these abiotic factors have a great impact on genome sizes. This is due to genome size independence from body size. Also, genome size could have served as an adaptive feature for bacteria in marine environments, explaining why different phyla may have diverged to accommodate their lifestyles.

Effects of Abiotic Factors on HIPV-Mediated Interactions between Plants and Parasitoids

PubMed Central

Becker, Christine; Desneux, Nicolas; Monticelli, Lucie; Fernandez, Xavier; Michel, Thomas; Lavoir, Anne-Violette

2015-01-01

In contrast to constitutively emitted plant volatiles (PV), herbivore-induced plant volatiles (HIPV) are specifically emitted by plants when afflicted with herbivores. HIPV can be perceived by parasitoids and predators which parasitize or prey on the respective herbivores, including parasitic hymenoptera. HIPV act as signals and facilitate host/prey detection. They comprise a blend of compounds: main constituents are terpenoids and “green leaf volatiles.” Constitutive emission of PV is well known to be influenced by abiotic factors like temperature, light intensity, water, and nutrient availability. HIPV share biosynthetic pathways with constitutively emitted PV and might therefore likewise be affected by abiotic conditions. However, the effects of abiotic factors on HIPV-mediated biotic interactions have received only limited attention to date. HIPV being influenced by the plant's growing conditions could have major implications for pest management. Quantitative and qualitative changes in HIPV blends may improve or impair biocontrol. Enhanced emission of HIPV may attract a larger number of natural enemies. Reduced emission rates or altered compositions, however, may render blends imperceptible to parasitoides and predators. Predicting the outcome of these changes is highly important for food production and for ecosystems affected by global climate change. PMID:26788501

Changes in abiotic influences on seed plants and ferns during 18 years of primary succession on Puerto Rican landslides

Treesearch

Lawrence R. Walker; Aaron B. Shiels; Peter J. Bellingham; Ashley D. Sparrow; Ned Fetcher; Fred H. Landau; Deborah J. Lodge

2013-01-01

Abiotic variables are critical drivers of succession in most primary seres, but how their influence on biota changes over time is rarely examined. Landslides provide good model systems for examining abiotic influences because they are spatially and temporally heterogeneous habitats with distinct abiotic and biotic gradients and post-landslide erosion. In an 18-year...

Contribution of biotic and abiotic factors in the natural attenuation of sulfamethoxazole: A path analysis approach.

PubMed

Li, Yan; Rashid, Azhar; Wang, Hongjie; Hu, Anyi; Lin, Lifeng; Yu, Chang-Ping; Chen, Meng; Sun, Qian

2018-08-15

Sulfamethoxazole (SMX) is a sulfonamide antibiotic, widely used as curative and preventive drug for human, animal, and aquaculture bacterial infections. Its residues have been ubiquitously detected in the surface waters and sediments. In the present study, SMX dissipation and kinetics was studied in the natural water samples from Jiulong River under simulated complex natural conditions as well as conditions to mimic various biotic and abiotic environmental conditions in isolation. Structural equation modeling (SEM) by employing partial least square technique in path coefficient analysis was used to investigate the direct and indirect contributions of different environmental factors in the natural attenuation of SMX. The model explained 81% of the variability in natural attenuation as a dependent variable under the influence of sole effects of direct photo-degradation, indirect photo-degradation, hydrolysis, microbial degradation and bacterial degradation. The results of SEM suggested that the direct and indirect photo-degradation were the major pathways in the SMX natural attenuation. However, other biotic and abiotic factors also play a mediatory role during the natural attenuation and other processes. Furthermore, the potential transformation products of SMX were identified and their toxicity was evaluated. Copyright © 2018 Elsevier B.V. All rights reserved.

Inter-annual variability of carbon fluxes in temperate forest ecosystems: effects of biotic and abiotic factors

NASA Astrophysics Data System (ADS)

Chen, M.; Keenan, T. F.; Hufkens, K.; Munger, J. W.; Bohrer, G.; Brzostek, E. R.; Richardson, A. D.

2014-12-01

Carbon dynamics in terrestrial ecosystems are influenced by both abiotic and biotic factors. Abiotic factors, such as variation in meteorological conditions, directly drive biophysical and biogeochemical processes; biotic factors, referring to the inherent properties of the ecosystem components, reflect the internal regulating effects including temporal dynamics and memory. The magnitude of the effect of abiotic and biotic factors on forest ecosystem carbon exchange has been suggested to vary at different time scales. In this study, we design and conduct a model-data fusion experiment to investigate the role and relative importance of the biotic and abiotic factors for inter-annual variability of the net ecosystem CO2 exchange (NEE) of temperate deciduous forest ecosystems in the Northeastern US. A process-based model (FöBAAR) is parameterized at four eddy-covariance sites using all available flux and biometric measurements. We conducted a "transplant" modeling experiment, that is, cross- site and parameter simulations with different combinations of site meteorology and parameters. Using wavelet analysis and variance partitioning techniques, analysis of model predictions identifies both spatial variant and spatially invariant parameters. Variability of NEE was primarily modulated by gross primary productivity (GPP), with relative contributions varying from hourly to yearly time scales. The inter-annual variability of GPP and NEE is more regulated by meteorological forcing, but spatial variability in certain model parameters (biotic response) has more substantial effects on the inter-annual variability of ecosystem respiration (Reco) through the effects on carbon pools. Both the biotic and abiotic factors play significant roles in modulating the spatial and temporal variability in terrestrial carbon cycling in the region. Together, our study quantifies the relative importance of both, and calls for better understanding of them to better predict regional CO2

Biotic and abiotic factors predicting the global distribution and population density of an invasive large mammal

PubMed Central

Lewis, Jesse S.; Farnsworth, Matthew L.; Burdett, Chris L.; Theobald, David M.; Gray, Miranda; Miller, Ryan S.

2017-01-01

Biotic and abiotic factors are increasingly acknowledged to synergistically shape broad-scale species distributions. However, the relative importance of biotic and abiotic factors in predicting species distributions is unclear. In particular, biotic factors, such as predation and vegetation, including those resulting from anthropogenic land-use change, are underrepresented in species distribution modeling, but could improve model predictions. Using generalized linear models and model selection techniques, we used 129 estimates of population density of wild pigs (Sus scrofa) from 5 continents to evaluate the relative importance, magnitude, and direction of biotic and abiotic factors in predicting population density of an invasive large mammal with a global distribution. Incorporating diverse biotic factors, including agriculture, vegetation cover, and large carnivore richness, into species distribution modeling substantially improved model fit and predictions. Abiotic factors, including precipitation and potential evapotranspiration, were also important predictors. The predictive map of population density revealed wide-ranging potential for an invasive large mammal to expand its distribution globally. This information can be used to proactively create conservation/management plans to control future invasions. Our study demonstrates that the ongoing paradigm shift, which recognizes that both biotic and abiotic factors shape species distributions across broad scales, can be advanced by incorporating diverse biotic factors. PMID:28276519

Effects of biotic and abiotic factors on the temporal dynamic of bat-fruit interactions

NASA Astrophysics Data System (ADS)

Laurindo, Rafael de Souza; Gregorin, Renato; Tavares, Davi Castro

2017-08-01

Mutualistic interactions between animals and plants vary over time and space based on the abundance of fruits or animals and seasonality. Little is known about this temporal dynamic and the influence of biotic and abiotic factors on the structure of interaction networks. We evaluated changes in the structure of network interactions between bats and fruits in relation to variations in rainfall. Our results suggest that fruit abundance is the main variable responsible for temporal changes in network attributes, such as network size, connectance, and number of interactions. In the same way, temperature positively affected the abundance of fruits and bats. An increase in temperature and alterations in rainfall patterns, due to human induced climate change, can cause changes in phenological patterns and fruit production, with negative consequences to biodiversity maintenance, ecological interactions, and ecosystem functioning.

Relationships between biotic and abiotic factors and regeneration of chestnut oak, white oak, and northern red oak

Treesearch

Songlin Fei; Kim C. Steiner; James C. Finley; Marc E. McDill

2003-01-01

A series of substantial field surveys of 38 mixed-oak stands in central Pennsylvania were carried out during 1996-2000. All the stands were surveyed 1 year prior to harvest, and 16 stands have been surveyed 1 year after harvest. Three abiotic factors at stand scale, four abiotic factors at plot scale, and two biotic factors and one abiotic factor at subplot scale was...

Revisiting the Role of Plant Transcription Factors in the Battle against Abiotic Stress.

PubMed

Khan, Sardar-Ali; Li, Meng-Zhan; Wang, Suo-Min; Yin, Hong-Ju

2018-05-31

Owing to diverse abiotic stresses and global climate deterioration, the agricultural production worldwide is suffering serious losses. Breeding stress-resilient crops with higher quality and yield against multiple environmental stresses via application of transgenic technologies is currently the most promising approach. Deciphering molecular principles and mining stress-associate genes that govern plant responses against abiotic stresses is one of the prerequisites to develop stress-resistant crop varieties. As molecular switches in controlling stress-responsive genes expression, transcription factors (TFs) play crucial roles in regulating various abiotic stress responses. Hence, functional analysis of TFs and their interaction partners during abiotic stresses is crucial to perceive their role in diverse signaling cascades that many researchers have continued to undertake. Here, we review current developments in understanding TFs, with particular emphasis on their functions in orchestrating plant abiotic stress responses. Further, we discuss novel molecular mechanisms of their action under abiotic stress conditions. This will provide valuable information for understanding regulatory mechanisms to engineer stress-tolerant crops.

Mycobacterium ulcerans dynamics in aquatic ecosystems are driven by a complex interplay of abiotic and biotic factors

PubMed Central

Garchitorena, Andrés; Guégan, Jean-François; Léger, Lucas; Eyangoh, Sara; Marsollier, Laurent; Roche, Benjamin

2015-01-01

Host–parasite interactions are often embedded within complex host communities and can be influenced by a variety of environmental factors, such as seasonal variations in climate or abiotic conditions in water and soil, which confounds our understanding of the main drivers of many multi-host pathogens. Here, we take advantage of a combination of large environmental data sets on Mycobacterium ulcerans (MU), an environmentally persistent microorganism associated to freshwater ecosystems and present in a large variety of aquatic hosts, to characterize abiotic and biotic factors driving the dynamics of this pathogen in two regions of Cameroon. We find that MU dynamics are largely driven by seasonal climatic factors and certain physico-chemical conditions in stagnant and slow-flowing ecosystems, with an important role of pH as limiting factor. Furthermore, water conditions can modify the effect of abundance and diversity of aquatic organisms on MU dynamics, which suggests a different contribution of two MU transmission routes for aquatic hosts (trophic vs environmental transmission) depending on local abiotic factors. DOI: http://dx.doi.org/10.7554/eLife.07616.001 PMID:26216042

Abiotic factors shape microbial diversity in Sonoran Desert soils.

PubMed

Andrew, David R; Fitak, Robert R; Munguia-Vega, Adrian; Racolta, Adriana; Martinson, Vincent G; Dontsova, Katerina

2012-11-01

High-throughput, culture-independent surveys of bacterial and archaeal communities in soil have illuminated the importance of both edaphic and biotic influences on microbial diversity, yet few studies compare the relative importance of these factors. Here, we employ multiplexed pyrosequencing of the 16S rRNA gene to examine soil- and cactus-associated rhizosphere microbial communities of the Sonoran Desert and the artificial desert biome of the Biosphere2 research facility. The results of our replicate sampling approach show that microbial communities are shaped primarily by soil characteristics associated with geographic locations, while rhizosphere associations are secondary factors. We found little difference between rhizosphere communities of the ecologically similar saguaro (Carnegiea gigantea) and cardón (Pachycereus pringlei) cacti. Both rhizosphere and soil communities were dominated by the disproportionately abundant Crenarchaeota class Thermoprotei, which comprised 18.7% of 183,320 total pyrosequencing reads from a comparatively small number (1,337 or 3.7%) of the 36,162 total operational taxonomic units (OTUs). OTUs common to both soil and rhizosphere samples comprised the bulk of raw sequence reads, suggesting that the shared community of soil and rhizosphere microbes constitute common and abundant taxa, particularly in the bacterial phyla Proteobacteria, Actinobacteria, Planctomycetes, Firmicutes, Bacteroidetes, Chloroflexi, and Acidobacteria. The vast majority of OTUs, however, were rare and unique to either soil or rhizosphere communities and differed among locations dozens of kilometers apart. Several soil properties, particularly soil pH and carbon content, were significantly correlated with community diversity measurements. Our results highlight the importance of culture-independent approaches in surveying microbial communities of extreme environments.

Abiotic Factors Shape Microbial Diversity in Sonoran Desert Soils

PubMed Central

Fitak, Robert R.; Munguia-Vega, Adrian; Racolta, Adriana; Martinson, Vincent G.; Dontsova, Katerina

2012-01-01

High-throughput, culture-independent surveys of bacterial and archaeal communities in soil have illuminated the importance of both edaphic and biotic influences on microbial diversity, yet few studies compare the relative importance of these factors. Here, we employ multiplexed pyrosequencing of the 16S rRNA gene to examine soil- and cactus-associated rhizosphere microbial communities of the Sonoran Desert and the artificial desert biome of the Biosphere2 research facility. The results of our replicate sampling approach show that microbial communities are shaped primarily by soil characteristics associated with geographic locations, while rhizosphere associations are secondary factors. We found little difference between rhizosphere communities of the ecologically similar saguaro (Carnegiea gigantea) and cardón (Pachycereus pringlei) cacti. Both rhizosphere and soil communities were dominated by the disproportionately abundant Crenarchaeota class Thermoprotei, which comprised 18.7% of 183,320 total pyrosequencing reads from a comparatively small number (1,337 or 3.7%) of the 36,162 total operational taxonomic units (OTUs). OTUs common to both soil and rhizosphere samples comprised the bulk of raw sequence reads, suggesting that the shared community of soil and rhizosphere microbes constitute common and abundant taxa, particularly in the bacterial phyla Proteobacteria, Actinobacteria, Planctomycetes, Firmicutes, Bacteroidetes, Chloroflexi, and Acidobacteria. The vast majority of OTUs, however, were rare and unique to either soil or rhizosphere communities and differed among locations dozens of kilometers apart. Several soil properties, particularly soil pH and carbon content, were significantly correlated with community diversity measurements. Our results highlight the importance of culture-independent approaches in surveying microbial communities of extreme environments. PMID:22885757

Can plant-natural enemy communication withstand disruption by biotic and abiotic factors?

PubMed

Clavijo McCormick, Andrea

2016-12-01

The attraction of natural enemies towards herbivore-induced plant volatiles is a well-documented phenomenon. However, the majority of published studies are carried under optimal water and nutrient regimes and with just one herbivore. But what happens when additional levels of ecological complexity are added? Does the presence of a second herbivore, microorganisms, and abiotic stress interfere with plant-natural enemy communication? or is communication stable enough to withstand disruption by additional biotic and abiotic factors?Investigating the effects of these additional levels of ecological complexity is key to understanding the stability of tritrophic interactions in natural ecosystems and may aid to forecast the impact of environmental disturbances on these, especially in climate change scenarios, which are often associated with modifications in plant and arthropod species distribution and increased levels of abiotic stress.This review explores the literature on natural enemy attraction to herbivore-induced volatiles when, besides herbivory, plants are challenged by additional biotic and abiotic factors.The aim of this review was to establish the impact of different biotic and abiotic factors on plant-natural enemy communication and to highlight critical aspects to guide future research efforts.

Earth, wind, and fire: Abiotic factors and the impacts of global environmental change on forest health

Treesearch

J.E. Lundquist; A.E. Camp; M.L. Tyrell; S.J. Seybold; P. Cannon; D.J. Lodge

2011-01-01

Trees do not just die; there is always a primary cause, and often contributing factors. Trees need adequate quantities of water, heat, light, nutrients, carbon dioxide, oxygen, and other abiotic resources to sustain life, growth, and reproduction. When these factors are deficient or excessive, they cause mortality. According to the concept of baseline mortality (...

Abiotic vs. biotic influences on habitat selection of coexisting species: Climate change impacts?

USGS Publications Warehouse

Martin, T.E.

2001-01-01

Species are commonly segregated along gradients of microclimate and vegetation. I explore the question of whether segregation is the result of microhabitat partitioning (biotic effects) or choice of differing microclimates (abiotic effects). I explored this question for four ground-nesting bird species that are segregated along a microclimate and vegetation gradient in Arizona. Birds shifted position of their nests on the microhabitat and microclimate gradient in response to changing precipitation over nine years. Similarly, annual bird abundance varied with precipitation across 12 yr. Those shifts in abundance and nesting microhabitat with changing precipitation demonstrate the importance of abiotic influences on bird distributions and habitat choice. However, nest-site shifts and microhabitat use also appear to be influenced by interactions among coexisting species. Moreover, shifts in habitat use by all species caused nest predation (i.e., biotic) costs that increased with increasing distance along the microclimate gradient. These results indicate that abiotic and biotic costs can strongly interact to influence microhabitat choice and abundances of coexisting species. Global climate change impacts have been considered largely in terms of simple distributional shifts, but these results indicate that shifts can also increase biotic costs when species move into habitat types for which they are poorly adapted or that create new biotic interactions.

Coupled nutrient removal and biomass production with mixed algal culture: impact of biotic and abiotic factors.

PubMed

Su, Yanyan; Mennerich, Artur; Urban, Brigitte

2012-08-01

The influence of biotic (algal inoculum concentration) and abiotic factors (illumination cycle, mixing velocity and nutrient strength) on the treatment efficiency, biomass generation and settleability were investigated with selected mixed algal culture. Dark condition led to poor nutrient removal efficiency. No significant difference in the N, P removal and biomass settleability between continuous and alternating illumination was observed, but a higher biomass generation capability for the continuous illumination was obtained. Different mixing velocity led to similar phosphorus removal efficiencies (above 98%) with different retention times. The reactor with 300 rpm mixing velocity had the best N removal capability. For the low strength wastewater, the N rates were 5.4±0.2, 9.1±0.3 and 10.8±0.3 mg/l/d and P removal rates were 0.57±0.03, 0.56±0.03 and 0.72±0.05 mg/l/d for reactors with the algal inoculum concentration of 0.2, 0.5 and 0.8 g/l, respectively. Low nutrient removal efficiency and poor biomass settleability were obtained for high strength wastewater. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of biotic and abiotic factors on resistance versus resilience of Douglas fir to drought.

PubMed

Carnwath, Gunnar; Nelson, Cara

2017-01-01

Significant increases in tree mortality due to drought-induced physiological stress have been documented worldwide. This trend is likely to continue with increased frequency and severity of extreme drought events in the future. Therefore, understanding the factors that influence variability in drought responses among trees will be critical to predicting ecosystem responses to climate change and developing effective management actions. In this study, we used hierarchical mixed-effects models to analyze drought responses of Pseudotsuga menziesii in 20 unmanaged forests stands across a broad range of environmental conditions in northeastern Washington, USA. We aimed to 1) identify the biotic and abiotic attributes most closely associated with the responses of individual trees to drought and 2) quantify the variability in drought responses at different spatial scales. We found that growth rates and competition for resources significantly affected resistance to a severe drought event in 2001: slow-growing trees and trees growing in subordinate canopy positions and/or with more neighbors suffered greater declines in radial growth during the drought event. In contrast, the ability of a tree to return to normal growth when climatic conditions improved (resilience) was unaffected by competition or relative growth rates. Drought responses were significantly influenced by tree age: older trees were more resistant but less resilient than younger trees. Finally, we found differences between resistance and resilience in spatial scale: a significant proportion (approximately 50%) of the variability in drought resistance across the study area was at broad spatial scales (i.e. among different forest types), most likely due to differences in the total amount of precipitation received at different elevations; in contrast, variation in resilience was overwhelmingly (82%) at the level of individual trees within stands and there was no difference in drought resilience among forest types

Effects of biotic and abiotic factors on resistance versus resilience of Douglas fir to drought

PubMed Central

Nelson, Cara

2017-01-01

Significant increases in tree mortality due to drought-induced physiological stress have been documented worldwide. This trend is likely to continue with increased frequency and severity of extreme drought events in the future. Therefore, understanding the factors that influence variability in drought responses among trees will be critical to predicting ecosystem responses to climate change and developing effective management actions. In this study, we used hierarchical mixed-effects models to analyze drought responses of Pseudotsuga menziesii in 20 unmanaged forests stands across a broad range of environmental conditions in northeastern Washington, USA. We aimed to 1) identify the biotic and abiotic attributes most closely associated with the responses of individual trees to drought and 2) quantify the variability in drought responses at different spatial scales. We found that growth rates and competition for resources significantly affected resistance to a severe drought event in 2001: slow-growing trees and trees growing in subordinate canopy positions and/or with more neighbors suffered greater declines in radial growth during the drought event. In contrast, the ability of a tree to return to normal growth when climatic conditions improved (resilience) was unaffected by competition or relative growth rates. Drought responses were significantly influenced by tree age: older trees were more resistant but less resilient than younger trees. Finally, we found differences between resistance and resilience in spatial scale: a significant proportion (approximately 50%) of the variability in drought resistance across the study area was at broad spatial scales (i.e. among different forest types), most likely due to differences in the total amount of precipitation received at different elevations; in contrast, variation in resilience was overwhelmingly (82%) at the level of individual trees within stands and there was no difference in drought resilience among forest types

Effects of biotic and abiotic factors on phenotypic partitioning of wing morphology and development in Sclerodermus pupariae (Hymenoptera: Bethylidae).

PubMed

Wang, Xiaoyi; Wei, Ke; Yang, Zhongqi; Jennings, David E; Duan, Jian J

2016-05-19

Wing phenotype polymorphism is commonly observed in insects, yet little is known about the influence of environmental cues on the development or expression of the alternative phenotypes. Here, we report how both biotic and abiotic factors affect the wing morph differentiation of a bethylid parasitoid Sclerodermus pupariae. The percentage of winged female parasitoid progeny increased exponentially with temperature between 20 °C to 30 °C. Low intensity light and short-day photoperiod conditions also significantly induced the development of winged morphs. Interestingly, wingless maternal parasitoids produced more winged progeny. Furthermore, the degree of wing dimorphism was significantly influenced by the interactions between light intensity and maternal wing morphs. The percentage of winged female progeny was not significantly influenced by foundress densities, but increased significantly with parasitoid brood sizes. However, the percentage of male progeny increased significantly with the densities of maternal parasitoids. Our findings highlight the phenotypic partitioning of wing morphology and development in the parasitoid S. pupariae under varied environmental cues, and reveal the most favourable conditions for the production of winged females in this bethylid wasp. It is thus possible to increase winged female parasitoid production for the purposes of biological control by manipulation of biotic and abiotic conditions.

Effect of biotic and abiotic factors on inter- and intra-event variability in stemflow rates in oak and pine stands in a Mediterranean mountain area

NASA Astrophysics Data System (ADS)

Cayuela, C.; Llorens, P.; Sánchez-Costa, E.; Levia, D. F.; Latron, J.

2018-05-01

Stemflow, despite being a small proportion of gross rainfall, is an important and understudied flux of water in forested areas. Recent studies have highlighted its complexity and relative importance for understanding soil and groundwater recharge. Stemflow dynamics offer an insight into how rain water is stored and released from the stems of trees to the soil. Past attempts have been made to understand the variability of stemflow under different types of vegetation, but rather few studies have focused on the combined influence of biotic and abiotic factors on inter and intra-storm stemflow variability, and none in Mediterranean climates. This study presents stemflow data collected at high temporal resolution for two species with contrasting canopies and bark characteristics: Quercus pubescens Willd. (downy oak) and Pinus sylvestris L. (Scots pine) in the Vallcebre research catchments (NE of Spain, 42° 12‧N, 1° 49‧E). The main objective was to understand how the interaction of biotic and abiotic factors affected stemflow dynamics. Mean stemflow production was low for both species (∼1% of incident rainfall) and increased with rainfall amount. However, the magnitude of the response depended on the combination of multiple biotic and abiotic factors. Both species produced similar stemflow volumes and the largest differences were found among trees of the same species. The combined analysis of biotic and abiotic factors showed that funneling ratios and stemflow dynamics were highly influenced by the interaction of rainfall intensity and tree size.

Transcription factors WRKY11 and WRKY17 are involved in abiotic stress responses in Arabidopsis.

PubMed

Ali, Muhammad Amjad; Azeem, Farrukh; Nawaz, Muhammad Amjad; Acet, Tuba; Abbas, Amjad; Imran, Qari Muhammad; Shah, Kausar Hussain; Rehman, Hafiz Mamoon; Chung, Gyuhwa; Yang, Seung Hwan; Bohlmann, Holger

2018-04-17

Plant WRKY transcription factors play a vital role in abiotic stress tolerance and regulation of plant defense responses. This study examined AtWRKY11 and AtWRKY17 expression under ABA, salt, and osmotic stress at different developmental stages in Arabidopsis. We used reverse transcriptase PCR, quantitative real-time PCR, and promoter:GUS lines to analyze expression. Both genes were upregulated in response to abiotic stress. Next, we applied the same stressors to seedlings of T-DNA insertion wrky11 and 17 knock-out mutants (single and double). Under stress, the mutants exhibited slower germination and compromised root growth compared with the wild type. In most cases, double-mutant seedlings were more affected than single mutants. These results suggest that wrky11 and wrky17 are not strictly limited to plant defense responses but are also involved in conferring stress tolerance. Copyright © 2018 Elsevier GmbH. All rights reserved.

Recent Advances in Utilizing Transcription Factors to Improve Plant Abiotic Stress Tolerance by Transgenic Technology

PubMed Central

Wang, Hongyan; Wang, Honglei; Shao, Hongbo; Tang, Xiaoli

2016-01-01

Agricultural production and quality are adversely affected by various abiotic stresses worldwide and this will be exacerbated by the deterioration of global climate. To feed a growing world population, it is very urgent to breed stress-tolerant crops with higher yields and improved qualities against multiple environmental stresses. Since conventional breeding approaches had marginal success due to the complexity of stress tolerance traits, the transgenic approach is now being popularly used to breed stress-tolerant crops. So identifying and characterizing the critical genes involved in plant stress responses is an essential prerequisite for engineering stress-tolerant crops. Far beyond the manipulation of single functional gene, engineering certain regulatory genes has emerged as an effective strategy now for controlling the expression of many stress-responsive genes. Transcription factors (TFs) are good candidates for genetic engineering to breed stress-tolerant crop because of their role as master regulators of many stress-responsive genes. Many TFs belonging to families AP2/EREBP, MYB, WRKY, NAC, bZIP have been found to be involved in various abiotic stresses and some TF genes have also been engineered to improve stress tolerance in model and crop plants. In this review, we take five large families of TFs as examples and review the recent progress of TFs involved in plant abiotic stress responses and their potential utilization to improve multiple stress tolerance of crops in the field conditions. PMID:26904044

Abscisic-acid-dependent basic leucine zipper (bZIP) transcription factors in plant abiotic stress.

PubMed

Banerjee, Aditya; Roychoudhury, Aryadeep

2017-01-01

One of the major causes of significant crop loss throughout the world is the myriad of environmental stresses including drought, salinity, cold, heavy metal toxicity, and ultraviolet-B (UV-B) rays. Plants as sessile organisms have evolved various effective mechanism which enable them to withstand this plethora of stresses. Most of such regulatory mechanisms usually follow the abscisic-acid (ABA)-dependent pathway. In this review, we have primarily focussed on the basic leucine zipper (bZIP) transcription factors (TFs) activated by the ABA-mediated signalosome. Upon perception of ABA by specialized receptors, the signal is transduced via various groups of Ser/Thr kinases, which phosphorylate the bZIP TFs. Following such post-translational modification of TFs, they are activated so that they bind to specific cis-acting sequences called abscisic-acid-responsive elements (ABREs) or GC-rich coupling elements (CE), thereby influencing the expression of their target downstream genes. Several in silico techniques have been adopted so far to predict the structural features, recognize the regulatory modification sites, undergo phylogenetic analyses, and facilitate genome-wide survey of TF under multiple stresses. Current investigations on the epigenetic regulation that controls greater accessibility of the inducible regions of DNA of the target gene to the bZIP TFs exclusively under stress situations, along with the evolved stress memory responses via genomic imprinting mechanism, have been highlighted. The potentiality of overexpression of bZIP TFs, either in a homologous or in a heterologous background, in generating transgenic plants tolerant to various abiotic stressors have also been addressed by various groups. The present review will provide a coherent documentation on the functional characterization and regulation of bZIP TFs under multiple environmental stresses, with the major goal of generating multiple-stress-tolerant plant cultivars in near future.

Spatially dependent biotic and abiotic factors drive survivorship and physical structure of green roof vegetation.

PubMed

Aloisio, Jason M; Palmer, Matthew I; Giampieri, Mario A; Tuininga, Amy R; Lewis, James D

2017-01-01

Plant survivorship depends on biotic and abiotic factors that vary at local and regional scales. This survivorship, in turn, has cascading effects on community composition and the physical structure of vegetation. Survivorship of native plant species is variable among populations planted in environmentally stressful habitats like urban roofs, but the degree to which factors at different spatial scales affect survivorship in urban systems is not well understood. We evaluated the effects of biotic and abiotic factors on survivorship, composition, and physical structure of two native perennial species assemblages, one characterized by a mixture of C 4 grasses and forbs (Hempstead Plains, HP) and one characterized by a mixture of C 3 grasses and forbs (Rocky Summit, RS), that were initially sown at equal ratios of growth forms (5:1:4; grass, N-fixing forb and non-N-fixing forb) in replicate 2-m 2 plots planted on 10 roofs in New York City (New York, USA). Of 24 000 installed plants, 40% survived 23 months after planting. Within-roof factors explained 71% of variation in survivorship, with biotic (species identity and assemblage) factors accounting for 54% of the overall variation, and abiotic (growing medium depth and plot location) factors explaining 17% of the variation. Among-roof factors explained 29% of variation in survivorship and increased solar radiation correlated with decreased survivorship. While growing medium properties (pH, nutrients, metals) differed among roofs there was no correlation with survivorship. Percent cover and sward height increased with increasing survivorship. At low survivorship, cover of the HP assemblage was greater compared to the RS assemblage. Sward height of the HP assemblage was about two times greater compared to the RS assemblage. These results highlight the effects of local biotic and regional abiotic drivers on community composition and physical structure of green roof vegetation. As a result, initial green roof plant

Microbial Hub Taxa Link Host and Abiotic Factors to Plant Microbiome Variation

PubMed Central

Agler, Matthew T.; Ruhe, Jonas; Kroll, Samuel; Morhenn, Constanze; Kim, Sang-Tae; Weigel, Detlef; Kemen, Eric M.

2016-01-01

Plant-associated microorganisms have been shown to critically affect host physiology and performance, suggesting that evolution and ecology of plants and animals can only be understood in a holobiont (host and its associated organisms) context. Host-associated microbial community structures are affected by abiotic and host factors, and increased attention is given to the role of the microbiome in interactions such as pathogen inhibition. However, little is known about how these factors act on the microbial community, and especially what role microbe–microbe interaction dynamics play. We have begun to address this knowledge gap for phyllosphere microbiomes of plants by simultaneously studying three major groups of Arabidopsis thaliana symbionts (bacteria, fungi and oomycetes) using a systems biology approach. We evaluated multiple potential factors of microbial community control: we sampled various wild A. thaliana populations at different times, performed field plantings with different host genotypes, and implemented successive host colonization experiments under lab conditions where abiotic factors, host genotype, and pathogen colonization was manipulated. Our results indicate that both abiotic factors and host genotype interact to affect plant colonization by all three groups of microbes. Considering microbe–microbe interactions, however, uncovered a network of interkingdom interactions with significant contributions to community structure. As in other scale-free networks, a small number of taxa, which we call microbial “hubs,” are strongly interconnected and have a severe effect on communities. By documenting these microbe–microbe interactions, we uncover an important mechanism explaining how abiotic factors and host genotypic signatures control microbial communities. In short, they act directly on “hub” microbes, which, via microbe–microbe interactions, transmit the effects to the microbial community. We analyzed two “hub” microbes (the

Connecting RNA Processing to Abiotic Environmental Response in Arabidopsis: the role of a polyadenylation factor

NASA Astrophysics Data System (ADS)

Li, Q. Q.; Xu, R.; Hunt, A. G.; Falcone, D. L.

Plants are constantly challenged by numerous environmental stresses both biotic and abiotic It is clear that plants have evolved to counter these stresses using all but limited means We recently discovered the potential role of a messenger RNA processing factor namely the Arabidopsis cleavage and polyadenylation specificity factor 30 kDa subunit AtCPSF30 when a mutant deficient in this factor displayed altered responses to an array of abiotic stresses This AtCPSF30 mutant named oxt6 exhibited an elevated tolerance to oxidative stress Microarray experiments of oxt6 and its complemented lines revealed an altered gene expression profile among which were antioxidative defense genes Interestingly the same gene encoding AtCPSF30 can also be transcribed into a large transcript that codes for a potential splicing factor Both protein products have a domain for RNA binding and a calmodulin binding domain activities of which have been confirmed by biochemical assays Surprisingly binding of AtCPSF30 to calmodulin inhibits the RNA-binding activity of the protein Mutational analysis shows that a small part of the protein is responsible for calmodulin binding and point mutations in this region abolished both RNA binding activity and the inhibition of this activity by calmodulin Analyses of the potential splicing factor are on going and the results will be presented The interesting possibilities for both the interplay between splicing and polyadenylation and the regulation of these processes by stimuli that act through

Multiple NUCLEAR FACTOR Y transcription factors respond to abiotic stress in Brassica napus L.

PubMed

Xu, Li; Lin, Zhongyuan; Tao, Qing; Liang, Mingxiang; Zhao, Gengmao; Yin, Xiangzhen; Fu, Ruixin

2014-01-01

Members of the plant NUCLEAR FACTOR Y (NF-Y) family are composed of the NF-YA, NF-YB, and NF-YC subunits. In Brassica napus (canola), each of these subunits forms a multimember subfamily. Plant NF-Ys were reported to be involved in several abiotic stresses. In this study, we demonstrated that multiple members of thirty three BnNF-Ys responded rapidly to salinity, drought, or ABA treatments. Transcripts of five BnNF-YAs, seven BnNF-YBs, and two BnNF-YCs were up-regulated by salinity stress, whereas the expression of thirteen BnNF-YAs, ten BnNF-YBs, and four BnNF-YCs were induced by drought stress. Under NaCl treatments, the expression of one BnNF-YA10 and four NF-YBs (BnNF-YB3, BnNF-YB7, BnNF-YB10, and BnNF-YB14) were greatly increased. Under PEG treatments, the expression levels of four NF-YAs (BnNF-YA9, BnNF-YA10, BnNF-YA11, and BnNF-YA12) and five NF-YBs (BnNF-YB1, BnNF-YB8, BnNF-YB10, BnNF-YB13, and BnNF-YB14) were greatly induced. The expression profiles of 20 of the 27 salinity- or drought-induced BnNF-Ys were also affected by ABA treatment. The expression levels of six NF-YAs (BnNF-YA1, BnNF-YA7, BnNF-YA8, BnNF-YA9, BnNF-YA10, and BnNF-YA12) and seven BnNF-YB members (BnNF-YB2, BnNF-YB3, BnNF-YB7, BnNF-YB10, BnNF-YB11, BnNF-YB13, and BnNF-YB14) and two NF-YC members (BnNF-YC2 and BnNF-YC3) were greatly up-regulated by ABA treatments. Only a few BnNF-Ys were inhibited by the above three treatments. Several NF-Y subfamily members exhibited collinear expression patterns. The promoters of all stress-responsive BnNF-Ys harbored at least two types of stress-related cis-elements, such as ABRE, DRE, MYB, or MYC. The cis-element organization of BnNF-Ys was similar to that of Arabidopsis thaliana, and the promoter regions exhibited higher levels of nucleotide sequence identity with Brassica rapa than with Brassica oleracea. This work represents an entry point for investigating the roles of canola NF-Y proteins during abiotic stress responses and provides insight into

Effects of biotic and abiotic factors on the oxygen content of green sea turtle nests during embryogenesis.

PubMed

Chen, Chiu-Lin; Wang, Chun-Chun; Cheng, I-Jiunn

2010-10-01

Several biotic and abiotic factors can influence nest oxygen content during embryogenesis. Several of these factors were determined during each developmental stage of green sea turtle embryos on Wan-an Island, Penghu Archipelago, Taiwan. We examined oxygen content in 7 nests in 2007 and 11 in 2008. Oxygen in the adjacent sand, total and viable clutch sizes, air, sand and nest temperatures, and sand characters of each nest were also determined. Oxygen content was lower in late stages than in the early and middle stages. It was also lower in the middle layer than in the upper and bottom layers. Nest temperature showed opposite trends, reaching its maximum value in late stages of development. Nest oxygen content was influenced by fraction of viable eggs, total clutch sizes, sand temperatures, maximum nest temperature and maximum change in the nest temperature during incubation. Clutch size during embryogenesis was the most influential factor overall. However, the major influential factors were different for different developmental stages. In the first half of the incubation, the development rate was low, and the change in the nest oxygen content was influenced mainly by the clutch size. During the second half, the rapid embryonic development rate became the dominant factor, and hatchling activities caused even greater oxygen consumption during the last stage of development.

Stressed out symbiotes: hypotheses for the influence of abiotic stress on arbuscular mycorrhizal fungi.

PubMed

Millar, Niall S; Bennett, Alison E

2016-11-01

Abiotic stress is a widespread threat to both plant and soil communities. Arbuscular mycorrhizal (AM) fungi can alleviate effects of abiotic stress by improving host plant stress tolerance, but the direct effects of abiotic stress on AM fungi are less well understood. We propose two hypotheses predicting how AM fungi will respond to abiotic stress. The stress exclusion hypothesis predicts that AM fungal abundance and diversity will decrease with persistent abiotic stress. The mycorrhizal stress adaptation hypothesis predicts that AM fungi will evolve in response to abiotic stress to maintain their fitness. We conclude that abiotic stress can have effects on AM fungi independent of the effects on the host plant. AM fungal communities will change in composition in response to abiotic stress, which may mean the loss of important individual species. This could alter feedbacks to the plant community and beyond. AM fungi will adapt to abiotic stress independent of their host plant. The adaptation of AM fungi to abiotic stress should allow the maintenance of the plant-AM fungal mutualism in the face of changing climates.

Novel NAC Transcription Factor TaNAC67 Confers Enhanced Multi-Abiotic Stress Tolerances in Arabidopsis

PubMed Central

Mao, Xinguo; Chen, Shuangshuang; Li, Ang; Zhai, Chaochao; Jing, Ruilian

2014-01-01

Abiotic stresses are major environmental factors that affect agricultural productivity worldwide. NAC transcription factors play pivotal roles in abiotic stress signaling in plants. As a staple crop, wheat production is severely constrained by abiotic stresses whereas only a few NAC transcription factors have been characterized functionally. To promote the application of NAC genes in wheat improvement by biotechnology, a novel NAC gene designated TaNAC67 was characterized in common wheat. To determine its role, transgenic Arabidopsis overexpressing TaNAC67-GFP controlled by the CaMV-35S promoter was generated and subjected to various abiotic stresses for morphological and physiological assays. Gene expression showed that TaNAC67 was involved in response to drought, salt, cold and ABA treatments. Localization assays revealed that TaNAC67 localized in the nucleus. Morphological analysis indicated the transgenics had enhanced tolerances to drought, salt and freezing stresses, simultaneously supported by enhanced expression of multiple abiotic stress responsive genes and improved physiological traits, including strengthened cell membrane stability, retention of higher chlorophyll contents and Na+ efflux rates, improved photosynthetic potential, and enhanced water retention capability. Overexpression of TaNAC67 resulted in pronounced enhanced tolerances to drought, salt and freezing stresses, therefore it has potential for utilization in transgenic breeding to improve abiotic stress tolerance in crops. PMID:24427285

Stream pH as an abiotic gradient influencing distributions of trout in Pennsylvania streams

USGS Publications Warehouse

Kocovsky, P.M.; Carline, R.F.

2005-01-01

Elevation and stream slope are abiotic gradients that limit upstream distributions of brook trout Salvelinus fontinalis and brown trout Salmo trutta in streams. We sought to determine whether another abiotic gradient, base-flow pH, may also affect distributions of these two species in eastern North America streams. We used historical data from the Pennsylvania Fish and Boat Commission's fisheries management database to explore the effects of reach elevation, slope, and base-flow pH on distributional limits to brook trout and brown trout in Pennsylvania streams in the Appalachian Plateaus and Ridge and Valley physiographic provinces. Discriminant function analysis (DFA) was used to calculate a canonical axis that separated allopatric brook trout populations from allopatric brown trout populations and allowed us to assess which of the three independent variables were important gradients along which communities graded from allopatric brook trout to allopatric brown trout. Canonical structure coefficients from DFA indicated that in both physiographic provinces, stream base-flow pH and slope were important factors in distributional limits; elevation was also an important factor in the Ridge and Valley Province but not the Appalachian Plateaus Province. Graphs of each variable against the proportion of brook trout in a community also identified apparent zones of allopatry for both species on the basis of pH and stream slope. We hypothesize that pH-mediated interspecific competition that favors brook trout in competition with brown trout at lower pH is the most plausible mechanism for segregation of these two species along pH gradients. Our discovery that trout distributions in Pennsylvania are related to stream base-flow pH has important implications for brook trout conservation in acidified regions. Carefully designed laboratory and field studies will be required to test our hypothesis and elucidate the mechanisms responsible for the partitioning of brook trout and

Biotic and abiotic factors affecting stemflow variability in downy oak and Scots pine stands in Mediterranean conditions

NASA Astrophysics Data System (ADS)

Cayuela, Carles; Garcia-Estringana, Pablo; Latron, Jérôme; Llorens, Pilar

2015-04-01

Although stemflow is only a small portion of rainfall, it may represent an important local input of water and nutrients at the plant stem. Previous studies have shown that stemflow has a significant influence on hydrological and biogeochemical processes. Stemflow volume is affected by many biotic factors as species, age, branch or bark characteristics. Moreover, the seasonality of the rainfall regime in Mediterranean areas, which includes both frontal rainfall events and short convective storms, can add complexity to the rainfall-stemflow relationship. This work investigates stemflow dynamics and the influence of biotic and abiotic factors on stemflow rates in two Mediterranean stands during the leafed period - from May to October. The monitored stands are a Downy oak forest (Quercus pubescens) and a Scots pine forest (Pinus sylvestris), both located in the Vallcebre research catchments (NE Spain, 42° 12'N, 1° 49'E). The monitoring design of each plot consists of 7 stemflow rings connected to tipping-buckets, bulk rainfall measured in a nearby clearing and meteorological conditions above the canopies. All data were recorded at 5 min interval. Biometric characteristics of the measured trees were also measured. The analysis of 39 rainfall events (65% smaller than 10 mm) shows that stemflow accounted for less than 1% of the bulk rainfall in both stands. Results also show that, on average, the rainfall amount required for the start of the stemflow and the time delay between the beginning of the precipitation and the start of stemflow are higher in the Downy oak forest. As suggested by stemflow funneling ratios, these differences might be linked to the canopy structure and bark water storage capacity of the trees, indicating that during low magnitude events, oaks have more difficulty to reach storage capacity. The role of other biotic and abiotic parameters on stemflow variability in both stands is still under investigation.

The Effects of Abiotic Factors on Induced Volatile Emissions in Corn Plants1

PubMed Central

Gouinguené, Sandrine P.; Turlings, Ted C.J.

2002-01-01

Many plants respond to herbivory by releasing a specific blend of volatiles that is attractive to natural enemies of the herbivores. In corn (Zea mays), this induced odor blend is mainly composed of terpenoids and indole. The induced signal varies with plant species and genotype, but little is known about the variation due to abiotic factors. Here, we tested the effect of soil humidity, air humidity, temperature, light, and fertilization rate on the emission of induced volatiles in young corn plants. Each factor was tested separately under constant conditions for the other factors. Plants released more when standing in dry soil than in wet soil, whereas for air humidity, the optimal release was found at around 60% relative humidity. Temperatures between 22°C and 27°C led to a higher emission than lower or higher temperatures. Light intensity had a dramatic effect. The emission of volatiles did not occur in the dark and increased steadily with an increase in the light intensity. An experiment with an unnatural light-dark cycle showed that the release was fully photophase dependent. Fertilization also had a strong positive effect; the emission of volatiles was minimal when plants were grown under low nutrition, even when results were corrected for plant biomass. Changes in all abiotic factors caused small but significant changes in the relative ratios among the different compounds (quality) in the induced odor blends, except for air humidity. Hence, climatic conditions and nutrient availability can be important factors in determining the intensity and variability in the release of induced plant volatiles. PMID:12114583

Transcription Factors and Their Roles in Signal Transduction in Plants under Abiotic Stresses

PubMed Central

Hoang, Xuan Lan Thi; Nhi, Du Ngoc Hai; Thu, Nguyen Binh Anh; Thao, Nguyen Phuong; Tran, Lam-Son Phan

2017-01-01

Abstract: In agricultural production, abiotic stresses are known as the main disturbance leading to negative impacts on crop performance. Research on elucidating plant defense mechanisms against the stresses at molecular level has been addressed for years in order to identify the major contributors in boosting the plant tolerance ability. From literature, numerous genes from different species, and from both functional and regulatory gene categories, have been suggested to be on the list of potential candidates for genetic engineering. Noticeably, enhancement of plant stress tolerance by manipulating expression of Transcription Factors (TFs) encoding genes has emerged as a popular approach since most of them are early stress-responsive genes and control the expression of a set of downstream target genes. Consequently, there is a higher chance to generate novel cultivars with better tolerance to either single or multiple stresses. Perhaps, the difficult task when deploying this approach is selecting appropriate gene(s) for manipulation. In this review, on the basis of the current findings from molecular and post-genomic studies, our interest is to highlight the current understanding of the roles of TFs in signal transduction and mediating plant responses towards abiotic stressors. Furthermore, interactions among TFs within the stress-responsive network will be discussed. The last section will be reserved for discussing the potential applications of TFs for stress tolerance improvement in plants. PMID:29204078

Identification and Expression Profiling of the Auxin Response Factors in Dendrobium officinale under Abiotic Stresses

PubMed Central

Chen, Zhehao; Yuan, Ye; Fu, Di; Shen, Chenjia; Yang, Yanjun

2017-01-01

Auxin response factor (ARF) proteins play roles in plant responses to diverse environmental stresses by binding specifically to the auxin response element in the promoters of target genes. Using our latest public Dendrobium transcriptomes, a comprehensive characterization and analysis of 14 DnARF genes were performed. Three selected DnARFs, including DnARF1, DnARF4, and DnARF6, were confirmed to be nuclear proteins according to their transient expression in epidermal cells of Nicotiana benthamiana leaves. Furthermore, the transcription activation abilities of DnARF1, DnARF4, and DnARF6 were tested in a yeast system. Our data showed that DnARF6 is a transcriptional activator in Dendrobium officinale. To uncover the basic information of DnARF gene responses to abiotic stresses, we analyzed their expression patterns under various hormones and abiotic treatments. Based on our data, several hormones and significant stress responsive DnARF genes have been identified. Since auxin and ARF genes have been identified in many plant species, our data is imperative to reveal the function of ARF mediated auxin signaling in the adaptation to the challenging Dendrobium environment. PMID:28471373

Identification and Expression Profiling of the Auxin Response Factors in Dendrobium officinale under Abiotic Stresses.

PubMed

Chen, Zhehao; Yuan, Ye; Fu, Di; Shen, Chenjia; Yang, Yanjun

2017-05-04

Auxin response factor (ARF) proteins play roles in plant responses to diverse environmental stresses by binding specifically to the auxin response element in the promoters of target genes. Using our latest public Dendrobium transcriptomes, a comprehensive characterization and analysis of 14 DnARF genes were performed. Three selected DnARFs , including DnARF1 , DnARF4 , and DnARF6 , were confirmed to be nuclear proteins according to their transient expression in epidermal cells of Nicotiana benthamiana leaves. Furthermore, the transcription activation abilities of DnARF1 , DnARF4 , and DnARF6 were tested in a yeast system. Our data showed that DnARF6 is a transcriptional activator in Dendrobium officinale . To uncover the basic information of DnARF gene responses to abiotic stresses, we analyzed their expression patterns under various hormones and abiotic treatments. Based on our data, several hormones and significant stress responsive DnARF genes have been identified. Since auxin and ARF genes have been identified in many plant species, our data is imperative to reveal the function of ARF mediated auxin signaling in the adaptation to the challenging Dendrobium environment.

Plant distribution and stand characteristics in brackish marshes: Unravelling the roles of abiotic factors and interspecific competition

NASA Astrophysics Data System (ADS)

Carus, Jana; Heuner, Maike; Paul, Maike; Schröder, Boris

2017-09-01

Due to increasing pressure on estuarine marshes from sea level rise and river training, there is a growing need to understand how species-environment relationships influence the zonation and growth of tidal marsh vegetation. In the present study, we investigated the distribution and stand characteristics of the two key brackish marsh species Bolboschoenus maritimus and Phragmites australis in the Elbe estuary together with several abiotic habitat factors. We then tested the effect of these habitat factors on plant growth and zonation with generalised linear models (GLMs). Our study provides detailed information on the importance of single habitat factors and their interactions for controlling the distribution patterns and stand characteristics of two key marsh species. Our results suggest that flow velocity is the main factor influencing species distribution and stand characteristics and together with soil-water salinity even affects the inundation tolerance of the two specie investigated here. Additionally, inundation height and duration as well as interspecific competition helped explain the distribution patterns and stand characteristics. By identifying the drivers of marsh zonation and stand characteristics and quantifying their effects, this study provides useful information for evaluating a future contribution of tidal marsh vegetation to ecosystem-based shore protection.

Tissue specific and abiotic stress regulated transcription of histidine kinases in plants is also influenced by diurnal rhythm

PubMed Central

Singh, Anupama; Kushwaha, Hemant R.; Soni, Praveen; Gupta, Himanshu; Singla-Pareek, Sneh L.; Pareek, Ashwani

2015-01-01

Two-component system (TCS) is one of the key signal sensing machinery which enables species to sense environmental stimuli. It essentially comprises of three major components, sensory histidine kinase proteins (HKs), histidine phosphotransfer proteins (Hpts), and response regulator proteins (RRs). The members of the TCS family have already been identified in Arabidopsis and rice but the knowledge about their functional indulgence during various abiotic stress conditions remains meager. Current study is an attempt to carry out comprehensive analysis of the expression of TCS members in response to various abiotic stress conditions and in various plant tissues in Arabidopsis and rice using MPSS and publicly available microarray data. The analysis suggests that despite having almost similar number of genes, rice expresses higher number of TCS members during various abiotic stress conditions than Arabidopsis. We found that the TCS machinery is regulated by not only various abiotic stresses, but also by the tissue specificity. Analysis of expression of some representative members of TCS gene family showed their regulation by the diurnal cycle in rice seedlings, thus bringing-in another level of their transcriptional control. Thus, we report a highly complex and tight regulatory network of TCS members, as influenced by the tissue, abiotic stress signal, and diurnal rhythm. The insights on the comparative expression analysis presented in this study may provide crucial leads toward dissection of diverse role(s) of the various TCS family members in Arabidopsis and rice. PMID:26442025

Abiotic and biotic factors responsible for antimonite oxidation in Agrobacterium tumefaciens GW4

PubMed Central

Li, Jingxin; Yang, Birong; Shi, Manman; Yuan, Kai; Guo, Wei; Wang, Qian; Wang, Gejiao

2017-01-01

Antimonite [Sb(III)]-oxidizing bacteria can transform the toxic Sb(III) into the less toxic antimonate [Sb(V)]. Recently, the cytoplasmic Sb(III)-oxidase AnoA and the periplasmic arsenite [As(III)] oxidase AioAB were shown to responsible for bacterial Sb(III) oxidation, however, disruption of each gene only partially decreased Sb(III) oxidation efficiency. This study showed that in Agrobacterium tumefaciens GW4, Sb(III) induced cellular H2O2 content and H2O2 degradation gene katA. Gene knock-out/complementation of katA, anoA, aioA and anoA/aioA and Sb(III) oxidation and growth experiments showed that katA, anoA and aioA were essential for Sb(III) oxidation and resistance and katA was also essential for H2O2 resistance. Furthermore, linear correlations were observed between cellular H2O2 and Sb(V) content in vivo and chemical H2O2 and Sb(V) content in vitro (R2 = 0.93 and 0.94, respectively). These results indicate that besides the biotic factors, the cellular H2O2 induced by Sb(III) also catalyzes bacterial Sb(III) oxidation as an abiotic oxidant. The data reveal a novel mechanism that bacterial Sb(III) oxidation is associated with abiotic (cellular H2O2) and biotic (AnoA and AioAB) factors and Sb(III) oxidation process consumes cellular H2O2 which contributes to microbial detoxification of both Sb(III) and cellular H2O2. PMID:28252030

Abiotic and biotic factors responsible for antimonite oxidation in Agrobacterium tumefaciens GW4

NASA Astrophysics Data System (ADS)

Li, Jingxin; Yang, Birong; Shi, Manman; Yuan, Kai; Guo, Wei; Wang, Qian; Wang, Gejiao

2017-03-01

Antimonite [Sb(III)]-oxidizing bacteria can transform the toxic Sb(III) into the less toxic antimonate [Sb(V)]. Recently, the cytoplasmic Sb(III)-oxidase AnoA and the periplasmic arsenite [As(III)] oxidase AioAB were shown to responsible for bacterial Sb(III) oxidation, however, disruption of each gene only partially decreased Sb(III) oxidation efficiency. This study showed that in Agrobacterium tumefaciens GW4, Sb(III) induced cellular H2O2 content and H2O2 degradation gene katA. Gene knock-out/complementation of katA, anoA, aioA and anoA/aioA and Sb(III) oxidation and growth experiments showed that katA, anoA and aioA were essential for Sb(III) oxidation and resistance and katA was also essential for H2O2 resistance. Furthermore, linear correlations were observed between cellular H2O2 and Sb(V) content in vivo and chemical H2O2 and Sb(V) content in vitro (R2 = 0.93 and 0.94, respectively). These results indicate that besides the biotic factors, the cellular H2O2 induced by Sb(III) also catalyzes bacterial Sb(III) oxidation as an abiotic oxidant. The data reveal a novel mechanism that bacterial Sb(III) oxidation is associated with abiotic (cellular H2O2) and biotic (AnoA and AioAB) factors and Sb(III) oxidation process consumes cellular H2O2 which contributes to microbial detoxification of both Sb(III) and cellular H2O2.

Disentangling effects of abiotic factors and biotic interactions on cross-taxon congruence in species turnover patterns of plants, moths and beetles.

PubMed

Duan, Meichun; Liu, Yunhui; Yu, Zhenrong; Baudry, Jacques; Li, Liangtao; Wang, Changliu; Axmacher, Jan C

2016-04-01

High cross-taxon congruence in species diversity patterns is essential for the use of surrogate taxa in biodiversity conservation, but presence and strength of congruence in species turnover patterns, and the relative contributions of abiotic environmental factors and biotic interaction towards this congruence, remain poorly understood. In our study, we used variation partitioning in multiple regressions to quantify cross-taxon congruence in community dissimilarities of vascular plants, geometrid and arciinid moths and carabid beetles, subsequently investigating their respective underpinning by abiotic factors and biotic interactions. Significant cross-taxon congruence observed across all taxon pairs was linked to their similar responses towards elevation change. Changes in the vegetation composition were closely linked to carabid turnover, with vegetation structure and associated microclimatic conditions proposed causes of this link. In contrast, moth assemblages appeared to be dominated by generalist species whose turnover was weakly associated with vegetation changes. Overall, abiotic factors exerted a stronger influence on cross-taxon congruence across our study sites than biotic interactions. The weak congruence in turnover observed particularly between plants and moths highlights the importance of multi-taxon approaches based on groupings of taxa with similar turnovers, rather than the use of single surrogate taxa or environmental proxies, in biodiversity assessments.

Disentangling effects of abiotic factors and biotic interactions on cross-taxon congruence in species turnover patterns of plants, moths and beetles

PubMed Central

Duan, Meichun; Liu, Yunhui; Yu, Zhenrong; Baudry, Jacques; Li, Liangtao; Wang, Changliu; Axmacher, Jan C.

2016-01-01

High cross-taxon congruence in species diversity patterns is essential for the use of surrogate taxa in biodiversity conservation, but presence and strength of congruence in species turnover patterns, and the relative contributions of abiotic environmental factors and biotic interaction towards this congruence, remain poorly understood. In our study, we used variation partitioning in multiple regressions to quantify cross-taxon congruence in community dissimilarities of vascular plants, geometrid and arciinid moths and carabid beetles, subsequently investigating their respective underpinning by abiotic factors and biotic interactions. Significant cross-taxon congruence observed across all taxon pairs was linked to their similar responses towards elevation change. Changes in the vegetation composition were closely linked to carabid turnover, with vegetation structure and associated microclimatic conditions proposed causes of this link. In contrast, moth assemblages appeared to be dominated by generalist species whose turnover was weakly associated with vegetation changes. Overall, abiotic factors exerted a stronger influence on cross-taxon congruence across our study sites than biotic interactions. The weak congruence in turnover observed particularly between plants and moths highlights the importance of multi-taxon approaches based on groupings of taxa with similar turnovers, rather than the use of single surrogate taxa or environmental proxies, in biodiversity assessments. PMID:27032533

Overexpression of SlGRAS40 in Tomato Enhances Tolerance to Abiotic Stresses and Influences Auxin and Gibberellin Signaling

PubMed Central

Liu, Yudong; Huang, Wei; Xian, Zhiqiang; Hu, Nan; Lin, Dongbo; Ren, Hua; Chen, Jingxuan; Su, Deding; Li, Zhengguo

2017-01-01

Abiotic stresses are major environmental factors that inhibit plant growth and development impacting crop productivity. GRAS transcription factors play critical and diverse roles in plant development and abiotic stress. In this study, SlGRAS40, a member of the tomato (Solanum lycopersicum) GRAS family, was functionally characterized. In wild-type (WT) tomato, SlGRAS40 was upregulated by abiotic stress induced by treatment with D-mannitol, NaCl, or H2O2. Transgenic tomato plants overexpressing SlGRAS40 (SlGRAS40-OE) were more tolerant of drought and salt stress than WT. SlGRAS40-OE plants displayed pleiotropic phenotypes reminiscent of those resulting from altered auxin and/or gibberellin signaling. A comparison of WT and SlGRAS40-OE transcriptomes showed that the expression of a large number of genes involved in hormone signaling and stress responses were modified. Our study of SlGRAS40 protein provides evidence of how another GRAS plays roles in resisting abiotic stress and regulating auxin and gibberellin signaling during vegetative and reproductive growth in tomato. PMID:29018467

The wheat transcription factor, TabHLH39, improves tolerance to multiple abiotic stressors in transgenic plants.

PubMed

Zhai, Yiqian; Zhang, Lichao; Xia, Chuan; Fu, Silu; Zhao, Guangyao; Jia, Jizeng; Kong, Xiuying

2016-05-13

Although bHLH transcription factors play important roles regulating plant development and abiotic stress response and tolerance, few functional studies have been performed in wheat. In this study, we isolated and characterized a bHLH gene, TabHLH39, from wheat. The TabHLH39 gene is located on wheat chromosome 5DL, and the protein localized to the nucleus and activated transcription. TabHLH39 showed variable expression in roots, stems, leaves, glumes, pistils and stamens and was induced by polyethylene glycol, salt and cold treatments. Further analysis revealed that TabHLH39 overexpression in Arabidopsis significantly enhanced tolerance to drought, salt and freezing stress during the seedling stage, which was also demonstrated by enhanced abiotic stress-response gene expression and changes to several physiological indices. Therefore, TabHLH39 has potential in transgenic breeding applications to improve abiotic stress tolerance in crops. Copyright © 2016 Elsevier Inc. All rights reserved.

The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish

NASA Astrophysics Data System (ADS)

Wenger, Amelia S.; Whinney, James; Taylor, Brett; Kroon, Frederieke

2016-06-01

Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change.

The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish.

PubMed

Wenger, Amelia S; Whinney, James; Taylor, Brett; Kroon, Frederieke

2016-06-28

Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change.

The impact of individual and combined abiotic factors on daily otolith growth in a coral reef fish

PubMed Central

Wenger, Amelia S.; Whinney, James; Taylor, Brett; Kroon, Frederieke

2016-01-01

Coral reefs are increasingly subjected to both local and global stressors, however, there is limited information on how reef organisms respond to their combined effects under natural conditions. This field study examined the growth response of the damselfish Neopomacentrus bankieri to the individual and combined effects of multiple abiotic factors. Turbidity, temperature, tidal movement, and wave action were recorded every 10 minutes for four months, after which the daily otolith growth of N. bankieri was aligned with corresponding abiotic conditions. Temperature was the only significant driver of daily otolith increment width, with increasing temperatures resulting in decreasing width. Although tidal movement was not a significant driver of increment width by itself, the combined effect of tidal movement and temperature had a greater negative effect on growth than temperature alone. Our results indicate that temperature can drive changes in growth even at very fine scales, and demonstrate that the cumulative impact of abiotic factors can be substantially greater than individual effects. As abiotic factors continue to change in intensity and duration, the combined impacts of them will become increasingly important drivers of physiological and ecological change. PMID:27350589

Relative contribution of biotic and abiotic factors to the population density of the cassava green mite, Mononychellus tanajoa (Acari: Tetranychidae).

PubMed

Rêgo, Adriano S; Teodoro, Adenir V; Maciel, Anilde G S; Sarmento, Renato A

2013-08-01

The cassava green mite, Mononychellus tanajoa, is a key pest of cassava, Manihot esculenta Crantz (Euphorbiaceae), and it may be kept in check by naturally occurring predatory mites of the family Phytoseiidae. In addition to predatory mites, abiotic factors may also contribute to regulate pest mite populations in the field. Here, we evaluated the population densities of both M. tanajoa and the generalist predatory mite Euseius ho DeLeon (Acari: Phytoseiidae) over the cultivation cycle (11 months) of cassava in four study sites located around the city of Miranda do Norte, Maranhão, Brazil. The abiotic variables rainfall, temperature and relative humidity were also recorded throughout the cultivation cycle of cassava. We determined the relative importance of biotic (density of E. ho) and abiotic (rainfall, temperature and relative humidity) factors to the density of M. tanajoa. The density of M. tanajoa increased whereas the density of E. ho remained constant throughout time. A hierarchical partitioning analysis revealed that most of the variance for the density of M. tanajoa was explained by rainfall and relative humidity followed by E. ho density and temperature. We conclude that abiotic factors, especially rainfall, were the main mechanisms driving M. tanajoa densities.

Plant Abiotic Stress Proteomics: The Major Factors Determining Alterations in Cellular Proteome

PubMed Central

Kosová, Klára; Vítámvás, Pavel; Urban, Milan O.; Prášil, Ilja T.; Renaut, Jenny

2018-01-01

HIGHLIGHTS: Major environmental and genetic factors determining stress-related protein abundance are discussed.Major aspects of protein biological function including protein isoforms and PTMs, cellular localization and protein interactions are discussed.Functional diversity of protein isoforms and PTMs is discussed. Abiotic stresses reveal profound impacts on plant proteomes including alterations in protein relative abundance, cellular localization, post-transcriptional and post-translational modifications (PTMs), protein interactions with other protein partners, and, finally, protein biological functions. The main aim of the present review is to discuss the major factors determining stress-related protein accumulation and their final biological functions. A dynamics of stress response including stress acclimation to altered ambient conditions and recovery after the stress treatment is discussed. The results of proteomic studies aimed at a comparison of stress response in plant genotypes differing in stress adaptability reveal constitutively enhanced levels of several stress-related proteins (protective proteins, chaperones, ROS scavenging- and detoxification-related enzymes) in the tolerant genotypes with respect to the susceptible ones. Tolerant genotypes can efficiently adjust energy metabolism to enhanced needs during stress acclimation. Stress tolerance vs. stress susceptibility are relative terms which can reflect different stress-coping strategies depending on the given stress treatment. The role of differential protein isoforms and PTMs with respect to their biological functions in different physiological constraints (cellular compartments and interacting partners) is discussed. The importance of protein functional studies following high-throughput proteome analyses is presented in a broader context of plant biology. In summary, the manuscript tries to provide an overview of the major factors which have to be considered when interpreting data from proteomic

Abiotic factors and trap design modulate the performance of traps used to monitor the plum curculio.

PubMed

Lamothe, Steve; Chouinard, Gérald; Vincent, Charles

2008-12-01

All published studies on effects of abiotic factors on plum curculio, Conotrachelus nenuphar (Hersbt), adults have taken a retrospective approach. Here, we present the results of experiments where factors and their levels were determined and controlled a priori. We compared the effectiveness of miniature pyramidal traps (45 by 20 by 20 cm) constructed of four kind of materials--wood, geotextile, nylon screening, and corrugated plastic--to monitor overwintered and summer adults of univoltine plum curculio. We also studied the effects of photoperiod, temperature, wind, and rain on pyramidal trap effectiveness. The experiments, which were replicated over time, were done in two controlled chambers that were divided into four sections, corresponding to simulated combinations (wind or no wind/rain or no rain). The temperatures tested (15, 20, and 25 degrees C) were randomly assigned in the chambers. During scotophase, geotextile traps captured significantly more overwintered and summer adults than traps made of other materials. The maximum proportion of captures (for overwintered and summer adults) during photophase was obtained at 25 degrees C, and it was significantly different than captures at 15 and 20 degrees C. During scotophase, significantly more overwintered and summer plum curculios were caught at 20 and 25 degrees C than at 15 degrees C. Our experiments demonstrated that geotextile is a good alternative to wooden pyramidal trap. Our results suggest that captures were higher 1) at night, 2) during warmer periods (20 and 25 degrees C), 3) when wind velocity was low and 4) during or shortly after rainfall, and 5) that photoperiod is a factor having an important predictive value for plum curculio captures.

FATE OF PAH COMPOUNDS IN TWO SOIL TYPES: INFLUENCE OF VOLATILIZATION, ABIOTIC LOSS, AND BIOLOGICAL ACTIVITY

EPA Science Inventory

The fate of 14 polycyclic aromatic hydrocarbon (PAH) compounds was evaluated with regard to interphase transfer potential and mechanisms of treatment in soil under unsaturated conditions. Volatilization and abiotic and biotic fate of the PAHs were determined using two soils not p...

Global Expressions Landscape of NAC Transcription Factor Family and Their Responses to Abiotic Stresses in Citrullus lanatus

PubMed Central

Lv, Xiaolong; Lan, Shanrong; Guy, Kateta Malangisha; Yang, Jinghua; Zhang, Mingfang; Hu, Zhongyuan

2016-01-01

Watermelon (Citrullus lanatus) is one xerophyte that has relative higher tolerance to drought and salt stresses as well as more sensitivity to cold stress, compared with most model plants. These characteristics facilitate it a potential model crop for researches on salt, drought or cold tolerance. In this study, a genome-wide comprehensive analysis of the ClNAC transcription factor (TF) family was carried out for the first time, to investigate their transcriptional profiles and potential functions in response to these abiotic stresses. The expression profiling analysis reveals that several NAC TFs are highly responsive to abiotic stresses and development, for instance, subfamily IV NACs may play roles in maintaining water status under drought or salt conditions, as well as water and metabolites conduction and translocation toward fruit. In contrast, rapid and negative responses of most of the ClNACs to low-temperature adversity may be related to the sensitivity to cold stress. Crosstalks among these abiotic stresses and hormone (abscisic acid and jasmonic acid) pathways were also discussed based on the expression of ClNAC genes. Our results will provide useful insights for the functional mining of NAC family in watermelon, as well as into the mechanisms underlying abiotic tolerance in other cash crops. PMID:27491393

Global Expressions Landscape of NAC Transcription Factor Family and Their Responses to Abiotic Stresses in Citrullus lanatus.

PubMed

Lv, Xiaolong; Lan, Shanrong; Guy, Kateta Malangisha; Yang, Jinghua; Zhang, Mingfang; Hu, Zhongyuan

2016-08-05

Watermelon (Citrullus lanatus) is one xerophyte that has relative higher tolerance to drought and salt stresses as well as more sensitivity to cold stress, compared with most model plants. These characteristics facilitate it a potential model crop for researches on salt, drought or cold tolerance. In this study, a genome-wide comprehensive analysis of the ClNAC transcription factor (TF) family was carried out for the first time, to investigate their transcriptional profiles and potential functions in response to these abiotic stresses. The expression profiling analysis reveals that several NAC TFs are highly responsive to abiotic stresses and development, for instance, subfamily IV NACs may play roles in maintaining water status under drought or salt conditions, as well as water and metabolites conduction and translocation toward fruit. In contrast, rapid and negative responses of most of the ClNACs to low-temperature adversity may be related to the sensitivity to cold stress. Crosstalks among these abiotic stresses and hormone (abscisic acid and jasmonic acid) pathways were also discussed based on the expression of ClNAC genes. Our results will provide useful insights for the functional mining of NAC family in watermelon, as well as into the mechanisms underlying abiotic tolerance in other cash crops.

Impact of trap architecture, adjacent habitats, abiotic factors, and host plant phenology on captures of plum curculio (Coleoptera: Curculionidae) adults.

PubMed

Lafleur, Gérald; Chouinard, Gérald; Vincent, Charles; Cormier, Daniel

2007-06-01

Pyramid traps, 2.44 m and 3.66 m in height, were compared with standard-sized pyramid traps, 1.22 m in height, to assess the impact of trap architecture on captures of adult plum curculio, Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), in two apple (Malus spp.) orchards and a blueberry (Vaccinium spp.) planting. The effects of adjacent habitat (organic orchard versus wooded areas), abiotic factors, and phenological stages of apple also were assessed to determine whether these variables influenced trap captures. Standard-sized pyramidal traps captured significantly more adults than larger trap variants. In the apple orchards, most adults (70-80%) were captured before petal fall with the exception of blocks adjacent to the organic orchard (25%). Significantly more adults were captured along the edge of an apple orchard (managed using an integrated pest management strategy) facing an organic apple orchard (76%) than along the edge facing wooded areas (24%). There was a significant positive correlation between daily trap captures and mean daily temperatures before petal fall in apple orchards.

The importance of disturbance by fire and other abiotic and biotic factors in driving cheatgrass invasion varies based on invasion stage

Treesearch

Becky K. Kerns; Michelle A. Day

2017-01-01

Disturbances create fluctuations in resource availability that alter abiotic and biotic constraints. Exotic invader response may be due to multiple factors related to disturbance regimes and complex interactions between other small- and largescale abiotic and biotic processes that may vary across invasion stages. We explore how cheatgrass responds to both frequency and...

Abiotic drivers of Chihuahuan Desert plant communities

Treesearch

Laura Marie Ladwig

2014-01-01

Within grasslands, precipitation, fire, nitrogen (N) addition, and extreme temperatures influence community composition and ecosystem function. The differential influences of these abiotic factors on Chihuahuan Desert grassland communities was examined within the Sevilleta National Wildlife Refuge, located in central New Mexico, U.S.A. Although fire is a natural...

Spatial variation in abiotic and biotic factors in a floodplain determine anuran body size and growth rate at metamorphosis.

PubMed

Indermaur, Lukas; Schmidt, Benedikt R; Tockner, Klement; Schaub, Michael

2010-07-01

Body size at metamorphosis is a critical trait in the life history of amphibians. Despite the wide-spread use of amphibians as experimental model organisms, there is a limited understanding of how multiple abiotic and biotic factors affect the variation in metamorphic traits under natural conditions. The aim of our study was to quantify the effects of abiotic and biotic factors on spatial variation in the body size of tadpoles and size at metamorphosis of the European common toad (Bufo b. spinosus). Our study population was distributed over the riverbed (active tract) and the fringing riparian forest of a natural floodplain. The riverbed had warm ponds with variable hydroperiod and few predators, whereas the forest had ponds with the opposite characteristics. Spatial variation in body size at metamorphosis was governed by the interactive effects of abiotic and biotic factors. The particular form of the interaction between water temperature and intraspecific tadpole density suggests that abiotic factors laid the foundation for biotic factors: intraspecific density decreased growth only at high temperature. Predation and intraspecific density jointly reduced metamorphic size. Interspecific density had a negligible affect on body size at metamorphosis, suggesting weak inter-anuran interactions in the larval stage. Population density at metamorphosis was about one to two orders of magnitudes higher in the riverbed ponds than in the forest ponds, mainly because of lower tadpole mortality. Based on our results, we conclude that ponds in the riverbed appear to play a pivotal role for the population because tadpole growth and survival is best in this habitat.

Effects of abiotic factors on ecosystem health of Taihu Lake, China based on eco-exergy theory

NASA Astrophysics Data System (ADS)

Wang, Ce; Bi, Jun; Fath, Brian D.

2017-02-01

A lake ecosystem is continuously exposed to environmental stressors with non-linear interrelationships between abiotic factors and aquatic organisms. Ecosystem health depicts the capacity of system to respond to external perturbations and still maintain structure and function. In this study, we explored the effects of abiotic factors on ecosystem health of Taihu Lake in 2013, China from a system-level perspective. Spatiotemporal heterogeneities of eco-exergy and specific eco-exergy served as thermodynamic indicators to represent ecosystem health in the lake. The results showed the plankton community appeared more energetic in May, and relatively healthy in Gonghu Bay with both higher eco-exergy and specific eco-exergy; a eutrophic state was likely discovered in Zhushan Bay with higher eco-exergy but lower specific eco-exergy. Gradient Boosting Machine (GBM) approach was used to explain the non-linear relationships between two indicators and abiotic factors. This analysis revealed water temperature, inorganic nutrients, and total suspended solids greatly contributed to the two indicators that increased. However, pH rise driven by inorganic carbon played an important role in undermining ecosystem health, particularly when pH was higher than 8.2. This implies that climate change with rising CO2 concentrations has the potential to aggravate eutrophication in Taihu Lake where high nutrient loads are maintained.

Biotic and abiotic factors associated with altitudinal variation in plant traits and herbivory in a dominant oak species.

PubMed

Abdala-Roberts, Luis; Rasmann, Sergio; Berny-Mier Y Terán, Jorge C; Covelo, Felisa; Glauser, Gaétan; Moreira, Xoaquín

2016-12-01

It is generally thought that herbivore pressure is higher at lower elevations where climate is warmer and less seasonal, and that this has led to higher levels of plant defense investment at low elevations. However, the generality of this expectation has been called into question by recent studies. We tested for altitudinal gradients in insect leaf damage, plant defenses (phenolic compounds), and nutritional traits (phosphorus and nitrogen) in leaves of the long-lived tree Quercus robur, and further investigated the abiotic factors associated with such gradients. We sampled 20 populations of Q. robur distributed along an altitudinal gradient spanning 35-869 m above sea level, which covered most of the altitudinal range of this species and varied substantially in abiotic conditions, plant traits, and herbivory. Univariate regressions showed that leaf herbivory, phenolics, and phosphorus increased toward higher elevations, whereas leaf nitrogen did not vary with altitude. Multiple regression analyses indicated that temperature was the single most important factor associated with herbivory and appears to be strongly associated with altitudinal variation in damage. Leaf phenolics were also correlated with herbivory, but in a manner that suggests these chemical defenses do not underlie altitudinal variation in damage. In addition, we found that variation in leaf traits (phenolics and nutrients) was in turn associated with both climatic and soil variables. Overall, these findings suggest that altitudinal gradients in herbivory and defenses in Q. robur are uncoupled and that elevational variation in herbivory and plant traits responds mainly to abiotic factors. © 2016 Botanical Society of America.

Effects of abiotic factors on ecosystem health of Taihu Lake, China based on eco-exergy theory

PubMed Central

Wang, Ce; Bi, Jun; Fath, Brian D.

2017-01-01

A lake ecosystem is continuously exposed to environmental stressors with non-linear interrelationships between abiotic factors and aquatic organisms. Ecosystem health depicts the capacity of system to respond to external perturbations and still maintain structure and function. In this study, we explored the effects of abiotic factors on ecosystem health of Taihu Lake in 2013, China from a system-level perspective. Spatiotemporal heterogeneities of eco-exergy and specific eco-exergy served as thermodynamic indicators to represent ecosystem health in the lake. The results showed the plankton community appeared more energetic in May, and relatively healthy in Gonghu Bay with both higher eco-exergy and specific eco-exergy; a eutrophic state was likely discovered in Zhushan Bay with higher eco-exergy but lower specific eco-exergy. Gradient Boosting Machine (GBM) approach was used to explain the non-linear relationships between two indicators and abiotic factors. This analysis revealed water temperature, inorganic nutrients, and total suspended solids greatly contributed to the two indicators that increased. However, pH rise driven by inorganic carbon played an important role in undermining ecosystem health, particularly when pH was higher than 8.2. This implies that climate change with rising CO2 concentrations has the potential to aggravate eutrophication in Taihu Lake where high nutrient loads are maintained. PMID:28220835

Effect of abiotic factors on the mercury reduction process by humic acids in aqueous systems

USDA-ARS?s Scientific Manuscript database

Mercury (Hg) in the environment can have serious toxic effects on a variety of living organisms, and is a pollutant of concern worldwide. The reduction of mercury from the toxic Hg2+ form to Hg0 is especially important. One pathway for this reduction to occur is through an abiotic process with humic...

Distribution and Diversity of Soil Microfauna from East Antarctica: Assessing the Link between Biotic and Abiotic Factors

PubMed Central

Velasco-Castrillón, Alejandro; Schultz, Mark B.; Colombo, Federica; Gibson, John A. E.; Davies, Kerrie A.; Austin, Andrew D.; Stevens, Mark I.

2014-01-01

Terrestrial life in Antarctica has been described as some of the simplest on the planet, and mainly confined to soil microfaunal communities. Studies have suggested that the lack of diversity is due to extreme environmental conditions and thought to be driven by abiotic factors. In this study we investigated soil microfauna composition, abundance, and distribution in East Antarctica, and assessed correlations with soil geochemistry and environmental variables. We examined 109 soil samples from a wide range of ice-free habitats, spanning 2000 km from Framnes Mountains to Bailey Peninsula. Microfauna across all samples were patchily distributed, from complete absence of invertebrates to over 1600 specimens/gram of dry weight of soil (gdw), with highest microfauna abundance observed in samples with visible vegetation. Bdelloid rotifers were on average the most widespread found in 87% of sampled sites and the most abundant (44 specimens/gdw). Tardigrades occurred in 57% of the sampled sites with an abundance of 12 specimens/gdw. Nematodes occurred in 71% of samples with a total abundance of 3 specimens/gdw. Ciliates and mites were rarely found in soil samples, with an average abundance of 1.3 and 0.04 specimens/gdw, respectively. We found that microfaunal composition and abundance were mostly correlated with the soil geochemical parameters; phosphorus, NO3 − and salinity, and likely to be the result of soil properties and historic landscape formation and alteration, rather than the geographic region they were sampled from. Studies focusing on Antarctic biodiversity must take into account soil geochemical and environmental factors that influence population and species heterogeneity. PMID:24498126

Comparisons of stemflow and its bio-/abiotic influential factors between two xerophytic shrub species

NASA Astrophysics Data System (ADS)

Yuan, Chuan; Gao, Guangyao; Fu, Bojie

2017-03-01

Stemflow transports nutrient-enriched precipitation to the rhizosphere and functions as an efficient terrestrial flux in water-stressed ecosystems. However, its ecological significance has generally been underestimated because it is relatively limited in amount, and the biotic mechanisms that affect it have not been thoroughly studied at the leaf scale. This study was conducted during the 2014 and 2015 rainy seasons at the northern Loess Plateau of China. We measured the branch stemflow volume (SFb), shrub stemflow equivalent water depth (SFd), stemflow percentage of incident precipitation (SF %), stemflow productivity (SFP), funnelling ratio (FR), the meteorological characteristics and the plant traits of branches and leaves of C. korshinskii and S. psammophila. This study evaluated stemflow efficiency for the first time with the combined results of SFP and FR, and sought to determine the inter- and intra-specific differences of stemflow yield and efficiency between the two species, as well as the specific bio-/abiotic mechanisms that affected stemflow. The results indicated that C. korshinskii had a greater stemflow yield and efficiency at all precipitation levels than that of S. psammophila. The largest inter-specific difference generally occurred at the 5-10 mm branches during rains of ≤ 2 mm. Precipitation amount was the most influential meteorological characteristic that affected stemflow yield and efficiency in these two endemic shrub species. Branch angle was the most influential plant trait on FR. For SFb, stem biomass and leaf biomass were the most influential plant traits for C. korshinskii and S. psammophila, respectively. For SFP of these two shrub species, leaf traits (the individual leaf area) and branch traits (branch size and biomass allocation pattern) had a great influence during lighter rains ≤ 10 mm and heavier rains > 15 mm, respectively. The lower precipitation threshold to start stemflow allowed C. korshinskii (0.9 mm vs. 2

[Natural factors influencing sleep].

PubMed

Jurkowski, Marek K; Bobek-Billewicz, Barbara

2007-01-01

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

Enhanced bacoside production in shoot cultures of Bacopa monnieri under the influence of abiotic elicitors.

PubMed

Sharma, Munish; Ahuja, Ashok; Gupta, Rajinder; Mallubhotla, Sharada

2015-01-01

The effect of different abiotic elicitors [jasmonic acid, copper sulphate (CuSO4) and salicyclic acid] at varying concentrations on the stimulation of biomass and bacoside production in in vitro Bacopa monnieri shoot culture was studied. A systematic study conducted over a period of 35 days indicated that the maximum bacoside production (6.74 mg g(-1) dry weight (DW)) was obtained after a lag of 7 days and thereafter, the content decreased gradually to again increase at 28 days (5.91 mg g(-1) DW). Therefore, elicitation experiments were carried out over a period of 3, 6 and 9 days. The shoot cultures treated with 45 mg L(-1) of CuSO4 exhibited the highest bacoside content of 8.73 mg g(-1) DW (∼1.42-fold higher) than in control cultures (6.14 mg g(-1) DW). This study indicates the effectiveness of abiotic elicitation on bacoside production in in vitro shoot cultures of this medicinally important herb known for its memory-enhancing properties.

Abiotic Stress and Phyllosphere Bacteria Influence the Survival of Human Norovirus and Its Surrogates on Preharvest Leafy Greens

PubMed Central

Esseili, Malak A.; Gao, Xiang; Tegtmeier, Sarah; Saif, Linda J.

2015-01-01

Foodborne outbreaks of human noroviruses (HuNoVs) are frequently associated with leafy greens. Because there is no effective method to eliminate HuNoV from postharvest leafy greens, understanding virus survival under preharvest conditions is crucial. The objective of this study was to evaluate the survival of HuNoV and its surrogate viruses, murine norovirus (MNV), porcine sapovirus (SaV), and Tulane virus (TV), on preharvest lettuce and spinach that were subjected to abiotic stress (physical damage, heat, or flood). We also examined the bacteria culturable from the phyllosphere in response to abiotic stress and in relation to viral persistence. Mature plants were subjected to stressors 2 days prior to inoculation of the viruses on leaves. We quantified the viral RNA, determined the infectivity of the surrogates, and performed bacterial counts on postinoculation days (PIDs) 0, 1, 7, and 14. For both plant types, time exerted significant effects on HuNoV, MNV, SaV, and TV RNA titers, with greater effects being seen for the surrogates. Infectious surrogate viruses were undetectable on PID 14. Only physical damage on PID 14 significantly enhanced HuNoV RNA persistence on lettuce, while the three stressors differentially enhanced the persistence of MNV and TV RNA. Bacterial counts were significantly affected by time and plant type but not by the stressors. However, bacterial counts correlated significantly with HuNoV RNA titers on spinach and with the presence of surrogate viruses on both plant types under various conditions. In conclusion, abiotic stressors and phyllosphere bacterial density may differentially influence the survival of HuNoV and its surrogates on lettuce and spinach, emphasizing the need for the use of preventive measures at the preharvest stage. PMID:26497461

Abiotic association of PAEs with humic substances and its influence on the fate of PAEs in landfill leachate.

PubMed

Xiaoli, Chai; Rong, Ji; Jun, Wu; Huanhuan, Tong; Youcai, Zhao

2010-03-01

An equilibrium dialysis combined with a (14)C-labeling method was used to study the abiotic association of phthalic acid esters (PAEs) with dissolved humic substances (HS) and its influence on the fate of PAEs in landfill leachate. Elemental analysis and FTIR spectral analysis were carried out on the humic acid (HA) and fulvic acid (FA) components of HS to examine the relationship between the structure of HS and the intensity of the association of the PAEs with HS (K(A)). The results show that the association intensity of HS with PAEs depends greatly on both the properties of the PAEs and the source of HS. The HS have a strong association reaction with dibutyl phthalic acid, which might explain the higher concentration of dibutyl phthalic acid detected in landfill leachate. The pH value strongly affects the K(A) of HS, and it decreases radically when the pH increase from 3.0 to 9.0. The non-specific hydrophobic interaction between HS and PAEs plays a more important role in the abiotic association of HS with PAEs. Elemental analysis and FTIR spectra suggest that the high K(A) values are related to the high aromatic content and larger molecular weight of HS. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Factors Influencing Effective Writing.

ERIC Educational Resources Information Center

Muccino, Mary Ann; And Others

Focusing on procedures and strategies suitable for teaching writing to students in grades 4, 6, and 8, this paper examines the factors that have been shown through research to influence effective writing. The paper divides the research examined into the categories of metacognition; socially-based writing strategies; theory-tested approaches to…

Individual Cell Based Traits Obtained by Scanning Flow-Cytometry Show Selection by Biotic and Abiotic Environmental Factors during a Phytoplankton Spring Bloom

PubMed Central

Pomati, Francesco; Kraft, Nathan J. B.; Posch, Thomas; Eugster, Bettina; Jokela, Jukka; Ibelings, Bas W.

2013-01-01

In ecology and evolution, the primary challenge in understanding the processes that shape biodiversity is to assess the relationship between the phenotypic traits of organisms and the environment. Here we tested for selection on physio-morphological traits measured by scanning flow-cytometry at the individual level in phytoplankton communities under a temporally changing biotic and abiotic environment. Our aim was to study how high-frequency temporal changes in the environment influence biodiversity dynamics in a natural community. We focused on a spring bloom in Lake Zurich (Switzerland), characterized by rapid changes in phytoplankton, water conditions, nutrients and grazing (mainly mediated by herbivore ciliates). We described bloom dynamics in terms of taxonomic and trait-based diversity and found that diversity dynamics of trait-based groups were more pronounced than those of identified phytoplankton taxa. We characterized the linkage between measured phytoplankton traits, abiotic environmental factors and abundance of the main grazers and observed weak but significant correlations between changing abiotic and biotic conditions and measured size-related and fluorescence-related traits. We tested for deviations in observed community-wide distributions of focal traits from random patterns and found evidence for both clustering and even spacing of traits, occurring sporadically over the time series. Patterns were consistent with environmental filtering and phenotypic divergence under herbivore pressure, respectively. Size-related traits showed significant even spacing during the peak of herbivore abundance, suggesting that morphology-related traits were under selection from grazing. Pigment distribution within cells and colonies appeared instead to be associated with acclimation to temperature and water chemistry. We found support for trade-offs among grazing resistance and environmental tolerance traits, as well as for substantial periods of dynamics in which

Individual cell based traits obtained by scanning flow-cytometry show selection by biotic and abiotic environmental factors during a phytoplankton spring bloom.

PubMed

Pomati, Francesco; Kraft, Nathan J B; Posch, Thomas; Eugster, Bettina; Jokela, Jukka; Ibelings, Bas W

2013-01-01

In ecology and evolution, the primary challenge in understanding the processes that shape biodiversity is to assess the relationship between the phenotypic traits of organisms and the environment. Here we tested for selection on physio-morphological traits measured by scanning flow-cytometry at the individual level in phytoplankton communities under a temporally changing biotic and abiotic environment. Our aim was to study how high-frequency temporal changes in the environment influence biodiversity dynamics in a natural community. We focused on a spring bloom in Lake Zurich (Switzerland), characterized by rapid changes in phytoplankton, water conditions, nutrients and grazing (mainly mediated by herbivore ciliates). We described bloom dynamics in terms of taxonomic and trait-based diversity and found that diversity dynamics of trait-based groups were more pronounced than those of identified phytoplankton taxa. We characterized the linkage between measured phytoplankton traits, abiotic environmental factors and abundance of the main grazers and observed weak but significant correlations between changing abiotic and biotic conditions and measured size-related and fluorescence-related traits. We tested for deviations in observed community-wide distributions of focal traits from random patterns and found evidence for both clustering and even spacing of traits, occurring sporadically over the time series. Patterns were consistent with environmental filtering and phenotypic divergence under herbivore pressure, respectively. Size-related traits showed significant even spacing during the peak of herbivore abundance, suggesting that morphology-related traits were under selection from grazing. Pigment distribution within cells and colonies appeared instead to be associated with acclimation to temperature and water chemistry. We found support for trade-offs among grazing resistance and environmental tolerance traits, as well as for substantial periods of dynamics in which

Factors controlling the abiotic photo-degradation of monomethylmercury in surface waters

NASA Astrophysics Data System (ADS)

Black, Frank J.; Poulin, Brett A.; Flegal, A. Russell

2012-05-01

Photo-decomposition is among the most important mechanisms responsible for degrading monomethylmercury (MMHg) in aquatic systems, but this process is not fully understood. We investigated the relative importance of different factors in controlling the rate of MMHg photo-decomposition in surface waters in experiments using DOM isolated from natural waters. We found no evidence of net abiotic production of MMHg in any dark or light exposed treatments. The average (mean ± s.d.) MMHg photo-decomposition rate constant for all light exposed samples using DOM concentrated from three coastal wetlands was 0.0099 ± 0.0020 E-1m2 (range of 0.006-0.015 E-1m2) when expressed in photon flux from 330-700 nm. This was roughly 3-fold higher than the average MMHg photo-decomposition rate constant in coastal seawater of 0.0032 ± 0.0010 E-1m2. MMHg photo-degradation was highly wavelength dependent. The ratio of MMHg photo-decomposition rate constants, with respect to photon flux, was 400:37:1 for UVB:UVA:PAR. However, when integrated across the entire water column over which MMHg photo-demethylation occurs, PAR was responsible for photo-degrading more MMHg than UVB and UVA combined in the three wetland sites because of the more rapid attenuation of UV light with depth. MMHg half-lives in the wetlands were calculated for the upper 250 cm where photo-degradation occurred, and ranged from 7.6 to 20 days under typical summer sunlight conditions at 37°N. Rates of MMHg photo-decomposition decreased with increasing salinity, and were 27% higher at a salinity of 5 than those at a salinity of 25. This difference could not be accounted for by changes in the complexation of MMHg by DOM and chloride. Differences in MMHg photo-degradation rate constants of up to 18% were measured between treatments using DOM concentrated from three different wetlands. Surprisingly, increasing DOM concentration from 1.5 to 11.3 mg OC L-1 had only a small (6%) effect on MMHg photo-decomposition, which was much

Biotic and abiotic variables influencing plant litter breakdown in streams: a global study

PubMed Central

Pearson, Richard G.; Hui, Cang; Gessner, Mark O.; Pérez, Javier; Alexandrou, Markos A.; Graça, Manuel A. S.; Cardinale, Bradley J.; Albariño, Ricardo J.; Arunachalam, Muthukumarasamy; Barmuta, Leon A.; Boulton, Andrew J.; Bruder, Andreas; Callisto, Marcos; Chauvet, Eric; Death, Russell G.; Dudgeon, David; Encalada, Andrea C.; Ferreira, Verónica; Figueroa, Ricardo; Flecker, Alexander S.; Gonçalves, José F.; Helson, Julie; Iwata, Tomoya; Jinggut, Tajang; Mathooko, Jude; Mathuriau, Catherine; M'Erimba, Charles; Moretti, Marcelo S.; Pringle, Catherine M.; Ramírez, Alonso; Ratnarajah, Lavenia; Rincon, José; Yule, Catherine M.

2016-01-01

Plant litter breakdown is a key ecological process in terrestrial and freshwater ecosystems. Streams and rivers, in particular, contribute substantially to global carbon fluxes. However, there is little information available on the relative roles of different drivers of plant litter breakdown in fresh waters, particularly at large scales. We present a global-scale study of litter breakdown in streams to compare the roles of biotic, climatic and other environmental factors on breakdown rates. We conducted an experiment in 24 streams encompassing latitudes from 47.8° N to 42.8° S, using litter mixtures of local species differing in quality and phylogenetic diversity (PD), and alder (Alnus glutinosa) to control for variation in litter traits. Our models revealed that breakdown of alder was driven by climate, with some influence of pH, whereas variation in breakdown of litter mixtures was explained mainly by litter quality and PD. Effects of litter quality and PD and stream pH were more positive at higher temperatures, indicating that different mechanisms may operate at different latitudes. These results reflect global variability caused by multiple factors, but unexplained variance points to the need for expanded global-scale comparisons. PMID:27122551

Biotic and abiotic variables influencing plant litter breakdown in streams: a global study.

PubMed

Boyero, Luz; Pearson, Richard G; Hui, Cang; Gessner, Mark O; Pérez, Javier; Alexandrou, Markos A; Graça, Manuel A S; Cardinale, Bradley J; Albariño, Ricardo J; Arunachalam, Muthukumarasamy; Barmuta, Leon A; Boulton, Andrew J; Bruder, Andreas; Callisto, Marcos; Chauvet, Eric; Death, Russell G; Dudgeon, David; Encalada, Andrea C; Ferreira, Verónica; Figueroa, Ricardo; Flecker, Alexander S; Gonçalves, José F; Helson, Julie; Iwata, Tomoya; Jinggut, Tajang; Mathooko, Jude; Mathuriau, Catherine; M'Erimba, Charles; Moretti, Marcelo S; Pringle, Catherine M; Ramírez, Alonso; Ratnarajah, Lavenia; Rincon, José; Yule, Catherine M

2016-04-27

Plant litter breakdown is a key ecological process in terrestrial and freshwater ecosystems. Streams and rivers, in particular, contribute substantially to global carbon fluxes. However, there is little information available on the relative roles of different drivers of plant litter breakdown in fresh waters, particularly at large scales. We present a global-scale study of litter breakdown in streams to compare the roles of biotic, climatic and other environmental factors on breakdown rates. We conducted an experiment in 24 streams encompassing latitudes from 47.8° N to 42.8° S, using litter mixtures of local species differing in quality and phylogenetic diversity (PD), and alder (Alnus glutinosa) to control for variation in litter traits. Our models revealed that breakdown of alder was driven by climate, with some influence of pH, whereas variation in breakdown of litter mixtures was explained mainly by litter quality and PD. Effects of litter quality and PD and stream pH were more positive at higher temperatures, indicating that different mechanisms may operate at different latitudes. These results reflect global variability caused by multiple factors, but unexplained variance points to the need for expanded global-scale comparisons. © 2016 The Author(s).

A wheat salinity-induced WRKY transcription factor TaWRKY93 confers multiple abiotic stress tolerance in Arabidopsis thaliana.

PubMed

Qin, Yuxiang; Tian, Yanchen; Liu, Xiuzhi

2015-08-21

Wheat is an important crop in the world. But most of the cultivars are salt sensitive, and often adversely affected by salt stress. WRKY transcription factors play a major role in plant responses to salt stress, but the effective salinity regulatory WRKYs identified in bread wheat are limited and the mechanism of salt stress tolerance is also not well explored. Here, we identified a salt (NaCl) induced class II WRKY transcription factor TaWRKY93. Its transcript level was strongly induced by salt (NaCl) and exogenous abscisic acid (ABA). Over-expression of TaWRKY93 in Arabidopsis thaliana enhanced salt (NaCl), drought, low temperature and osmotic (mannitol) stress tolerance, mainly demonstrated by transgenic plants forming longer primary roots or more lateral roots on MS plates supplemented with NaCl and mannitol individually, higher survival rate under drought and low temperature stress. Further, transgenic plants maintained a more proline content, higher relative water content and less electrolyte leakage than the wild type plants. The transcript abundance of a series of abiotic stress-related genes was up-regulated in the TaWRKY93 transgenic plants. In summary, TaWRKY93 is a new positive regulator of abiotic stress, it may increase salinity, drought and low temperature stress tolerance through enhancing osmotic adjustment, maintaining membrane stability and increasing transcription of stress related genes, and contribute to the superior agricultural traits of SR3 through promoting root development. It can be used as a candidate gene for wheat transgenic engineering breeding against abiotic stress. Copyright © 2015 Elsevier Inc. All rights reserved.

ABI-like transcription factor gene TaABL1 from wheat improves multiple abiotic stress tolerances in transgenic plants.

PubMed

Xu, Dong-Bei; Gao, Shi-Qing; Ma, You-Zhi; Xu, Zhao-Shi; Zhao, Chang-Ping; Tang, Yi-Miao; Li, Xue-Yin; Li, Lian-Cheng; Chen, Yao-Feng; Chen, Ming

2014-12-01

The phytohormone abscisic acid (ABA) plays crucial roles in adaptive responses of plants to abiotic stresses. ABA-responsive element binding proteins (AREBs) are basic leucine zipper transcription factors that regulate the expression of downstream genes containing ABA-responsive elements (ABREs) in promoter regions. A novel ABI-like (ABA-insensitive) transcription factor gene, named TaABL1, containing a conserved basic leucine zipper (bZIP) domain was cloned from wheat. Southern blotting showed that three copies were present in the wheat genome. Phylogenetic analyses indicated that TaABL1 belonged to the AREB subfamily of the bZIP transcription factor family and was most closely related to ZmABI5 in maize and OsAREB2 in rice. Expression of TaABL1 was highly induced in wheat roots, stems, and leaves by ABA, drought, high salt, and low temperature stresses. TaABL1 was localized inside the nuclei of transformed wheat mesophyll protoplast. Overexpression of TaABL1 enhanced responses of transgenic plants to ABA and hastened stomatal closure under stress, thereby improving tolerance to multiple abiotic stresses. Furthermore, overexpression of TaABL1 upregulated or downregulated the expression of some stress-related genes controlling stomatal closure in transgenic plants under ABA and drought stress conditions, suggesting that TaABL1 might be a valuable genetic resource for transgenic molecular breeding.

Review of Microbial Responses to Abiotic Environmental Factors in the Context of the Proposed Yucca Mountain Repository

SciTech Connect

Meike, A.; Stroes-Gascoyne, S.

2000-08-01

A workshop on Microbial Activities at Yucca Mountain (May 1995, Lafayette, CA) was held with the intention to compile information on all pertinent aspects of microbial activity for application to a potential repository at Yucca Mountain. The findings of this workshop set off a number of efforts intended to eventually incorporate the impacts of microbial behavior into performance assessment models. One effort was to expand an existing modeling approach to include the distinctive characteristics of a repository at Yucca Mountain (e.g., unsaturated conditions and a significant thermal load). At the same time, a number of experimental studies were initiated asmore » well as a compilation of relevant literature to more thoroughly study the physical, chemical and biological parameters that would affect microbial activity under Yucca Mountain-like conditions. This literature search (completed in 1996) is the subject of the present document. The collected literature can be divided into four categories: (1) abiotic factors, (2) community dynamics and in-situ considerations, (3) nutrient considerations and (4) transport of radionuclides. The complete bibliography represents a considerable resource, but is too large to be discussed in one document. Therefore, the present report focuses on the first category, abiotic factors, and a discussion of these factors in order to facilitate the development of a model for Yucca Mountain.« less

Differential effects of abiotic factors and host plant traits on diversity and community composition of root-colonizing arbuscular mycorrhizal fungi in a salt-stressed ecosystem.

PubMed

Guo, Xiaohong; Gong, Jun

2014-02-01

Arbuscular mycorrhizal fungi (AMF) were investigated in roots of 18 host plant species in a salinized south coastal plain of Laizhou Bay, China. From 18 clone libraries of 18S rRNA genes, all of the 22 AMF phylotypes were identified into Glomus, of which 18 and 4 were classified in group A and B in the phylogenetic tree, respectively. The phylotypes related to morphologically defined Glomus species occurred generally in soil with higher salinity. AMF phylotype richness, Shannon index, and evenness were not significantly different between root samples from halophytes vs. non-halophytes, invades vs. natives, or annuals vs. perennials. However, AMF diversity estimates frequently differed along the saline gradient or among locations, but not among pH gradients. Moreover, UniFrac tests showed that both plant traits (salt tolerance, life style or origin) and abiotic factors (salinity, pH, or location) significantly affected the community composition of AMF colonizers. Redundancy and variation partitioning analyses revealed that soil salinity and pH, which respectively explained 6.9 and 4.2 % of the variation, were the most influential abiotic variables in shaping the AMF community structure. The presented data indicate that salt tolerance, life style, and origin traits of host species may not significantly affect the AMF diversity in roots, but do influence the community composition in this salinized ecosystem. The findings also highlight the importance of soil salinity and pH in driving the distribution of AMF in plant and soil systems.

Genome-wide characterization and expression profiling of NAC transcription factor genes under abiotic stresses in radish (Raphanus sativus L.)

PubMed Central

Muleke, Everlyne M’mbone; Jabir, Bashir Mohammed; Xie, Yang; Zhu, Xianwen; Cheng, Wanwan

2017-01-01

NAC (NAM, no apical meristem; ATAF, Arabidopsis transcription activation factor and CUC, cup-shaped cotyledon) proteins are among the largest transcription factor (TF) families playing fundamental biological processes, including cell expansion and differentiation, and hormone signaling in response to biotic and abiotic stresses. In this study, 172 RsNACs comprising 17 membrane-bound members were identified from the whole radish genome. In total, 98 RsNAC genes were non-uniformly distributed across the nine radish chromosomes. In silico analysis revealed that expression patterns of several NAC genes were tissue-specific such as a preferential expression in roots and leaves. In addition, 21 representative NAC genes were selected to investigate their responses to heavy metals (HMs), salt, heat, drought and abscisic acid (ABA) stresses using real-time polymerase chain reaction (RT-qPCR). As a result, differential expressions among these genes were identified where RsNAC023 and RsNAC080 genes responded positively to all stresses except ABA, while RsNAC145 responded more actively to salt, heat and drought stresses compared with other genes. The results provides more valuable information and robust candidate genes for future functional analysis for improving abiotic stress tolerances in radish. PMID:29259849

The WRKY transcription factors in the diploid woodland strawberry Fragaria vesca: Identification and expression analysis under biotic and abiotic stresses.

PubMed

Wei, Wei; Hu, Yang; Han, Yong-Tao; Zhang, Kai; Zhao, Feng-Li; Feng, Jia-Yue

2016-08-01

WRKY proteins comprise a large family of transcription factors that play important roles in response to biotic and abiotic stresses and in plant growth and development. To date, little is known about the WRKY gene family in strawberry. In this study, we identified 62 WRKY genes (FvWRKYs) in the wild diploid woodland strawberry (Fragaria vesca, 2n = 2x = 14) accession Heilongjiang-3. According to the phylogenetic analysis and structural features, these identified strawberry FvWRKY genes were classified into three main groups. In addition, eight FvWRKY-GFP fusion proteins showed distinct subcellular localizations in Arabidopsis mesophyll protoplasts. Furthermore, we examined the expression of the 62 FvWRKY genes in 'Heilongjiang-3' under various conditions, including biotic stress (Podosphaera aphanis), abiotic stresses (drought, salt, cold, and heat), and hormone treatments (abscisic acid, ethephon, methyl jasmonate, and salicylic acid). The expression levels of 33 FvWRKY genes were upregulated, while 12 FvWRKY genes were downregulated during powdery mildew infection. FvWRKY genes responded to drought and salt treatment to a greater extent than to temperature stress. Expression profiles derived from quantitative real-time PCR suggested that 11 FvWRKY genes responded dramatically to various stimuli at the transcriptional level, indicating versatile roles in responses to biotic and abiotic stresses. Interaction networks revealed that the crucial pathways controlled by WRKY proteins may be involved in the differential response to biotic stress. Taken together, the present work may provide the basis for future studies of the genetic modification of WRKY genes for pathogen resistance and stress tolerance in strawberry. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Abiotic and Biotic Factors Regulating Inter-Kingdom Engagement between Insects and Microbe Activity on Vertebrate Remains

PubMed Central

Jordan, Heather R.; Tomberlin, Jeffery K.

2017-01-01

A number of abiotic and biotic factors are known to regulate arthropod attraction, colonization, and utilization of decomposing vertebrate remains. Such information is critical when assessing arthropod evidence associated with said remains in terms of forensic relevance. Interactions are not limited to just between the resource and arthropods. There is another biotic factor that has been historically overlooked; however, with the advent of high-throughput sequencing, and other molecular techniques, the curtain has been pulled back to reveal a microscopic world that is playing a major role with regards to carrion decomposition patterns in association with arthropods. The objective of this publication is to review many of these factors and draw attention to their impact on microbial, specifically bacteria, activity associated with these remains as it is our contention that microbes serve as a primary mechanism regulating associated arthropod behavior. PMID:28538664

Abiotic influences on bicarbonate use in the giant kelp, Macrocystis pyrifera, in the Monterey Bay.

PubMed

Drobnitch, Sarah Tepler; Nickols, Kerry; Edwards, Matthew

2017-02-01

In the Monterey Bay region of central California, the giant kelp Macrocystis pyrifera experiences broad fluctuations in wave forces, temperature, light availability, nutrient availability, and seawater carbonate chemistry, all of which may impact their productivity. In particular, current velocities and light intensity may strongly regulate the supply and demand of inorganic carbon (Ci) as substrates for photosynthesis. Macrocystis pyrifera can acquire and utilize both CO 2 and bicarbonate (HCO 3 - ) as Ci substrates for photosynthesis and growth. Given the variability in carbon delivery (due to current velocities and varying [DIC]) and demand (in the form of saturating irradiance), we hypothesized that the proportion of CO 2 and bicarbonate utilized is not constant for M. pyrifera, but a variable function of their fluctuating environment. We further hypothesized that populations acclimated to different wave exposure and irradiance habitats would display different patterns of bicarbonate uptake. To test these hypotheses, we carried out oxygen evolution trials in the laboratory to measure the proportion of bicarbonate utilized by M. pyrifera via external CA under an orthogonal cross of velocity, irradiance, and acclimation treatments. Our Monterey Bay populations of M. pyrifera exhibited proportionally higher external bicarbonate utilization in high irradiance and high flow velocity conditions than in sub-saturating irradiance or low flow velocity conditions. However, there was no significant difference in proportional bicarbonate use between deep blades and canopy blades, nor between individuals from wave-exposed versus wave-protected sites. This study contributes a new field-oriented perspective on the abiotic controls of carbon utilization physiology in macroalgae. © 2016 Phycological Society of America.

Biotic and Abiotic Soil Properties Influence Survival of Listeria monocytogenes in Soil

PubMed Central

Locatelli, Aude; Spor, Aymé; Jolivet, Claudy; Piveteau, Pascal; Hartmann, Alain

2013-01-01

Listeria monocytogenes is a food-borne pathogen responsible for the potentially fatal disease listeriosis and terrestrial ecosystems have been hypothesized to be its natural reservoir. Therefore, identifying the key edaphic factors that influence its survival in soil is critical. We measured the survival of L. monocytogenes in a set of 100 soil samples belonging to the French Soil Quality Monitoring Network. This soil collection is meant to be representative of the pedology and land use of the whole French territory. The population of L. monocytogenes in inoculated microcosms was enumerated by plate count after 7, 14 and 84 days of incubation. Analysis of survival profiles showed that L. monocytogenes was able to survive up to 84 days in 71% of the soils tested, in the other soils (29%) only a short-term survival (up to 7 to 14 days) was observed. Using variance partitioning techniques, we showed that about 65% of the short-term survival ratio of L. monocytogenes in soils was explained by the soil chemical properties, amongst which the basic cation saturation ratio seems to be the main driver. On the other hand, while explaining a lower amount of survival ratio variance (11%), soil texture and especially clay content was the main driver of long-term survival of L. monocytogenes in soils. In order to assess the effect of the endogenous soils microbiota on L. monocytogenes survival, sterilized versus non-sterilized soils microcosms were compared in a subset of 9 soils. We found that the endogenous soil microbiota could limit L. monocytogenes survival especially when soil pH was greater than 7, whereas in acidic soils, survival ratios in sterilized and unsterilized microcosms were not statistically different. These results point out the critical role played by both the endogenous microbiota and the soil physic-chemical properties in determining the survival of L. monocytogenes in soils. PMID:24116083

Genome-wide characterization and analysis of bZIP transcription factor gene family related to abiotic stress in cassava.

PubMed

Hu, Wei; Yang, Hubiao; Yan, Yan; Wei, Yunxie; Tie, Weiwei; Ding, Zehong; Zuo, Jiao; Peng, Ming; Li, Kaimian

2016-03-07

The basic leucine zipper (bZIP) transcription factor family plays crucial roles in various aspects of biological processes. Currently, no information is available regarding the bZIP family in the important tropical crop cassava. Herein, 77 bZIP genes were identified from cassava. Evolutionary analysis indicated that MebZIPs could be divided into 10 subfamilies, which was further supported by conserved motif and gene structure analyses. Global expression analysis suggested that MebZIPs showed similar or distinct expression patterns in different tissues between cultivated variety and wild subspecies. Transcriptome analysis of three cassava genotypes revealed that many MebZIP genes were activated by drought in the root of W14 subspecies, indicating the involvement of these genes in the strong resistance of cassava to drought. Expression analysis of selected MebZIP genes in response to osmotic, salt, cold, ABA, and H2O2 suggested that they might participate in distinct signaling pathways. Our systematic analysis of MebZIPs reveals constitutive, tissue-specific and abiotic stress-responsive candidate MebZIP genes for further functional characterization in planta, yields new insights into transcriptional regulation of MebZIP genes, and lays a foundation for understanding of bZIP-mediated abiotic stress response.

The Novel Wheat Transcription Factor TaNAC47 Enhances Multiple Abiotic Stress Tolerances in Transgenic Plants

PubMed Central

Zhang, Lina; Zhang, Lichao; Xia, Chuan; Zhao, Guangyao; Jia, Jizeng; Kong, Xiuying

2016-01-01

NAC transcription factors play diverse roles in plant development and responses to abiotic stresses. However, the biological roles of NAC family members in wheat are not well understood. Here, we reported the isolation and functional characterization of a novel wheat TaNAC47 gene. TaNAC47 encoded protein, localizing in the nucleus, is able to bind to the ABRE cis-element and transactivate transcription in yeast, suggesting that it likely functions as a transcriptional activator. We also showed that TaNAC47 is differentially expressed in different tissues, and its expression was induced by the stress treatments of salt, cold, polyethylene glycol and exogenous abscisic acid. Furthermore, overexpression of TaNAC47 in Arabidopsis resulted in ABA hypersensitivity and enhancing tolerance of transgenic plants to drought, salt, and freezing stresses. Strikingly, overexpression of TaNAC47 was found to activate the expression of downstream genes and change several physiological indices that may enable transgenic plants to overcome unfavorable environments. Taken together, these results uncovered an important role of wheat TaNAC47 gene in response to ABA and abiotic stresses. PMID:26834757

The Novel Wheat Transcription Factor TaNAC47 Enhances Multiple Abiotic Stress Tolerances in Transgenic Plants.

PubMed

Zhang, Lina; Zhang, Lichao; Xia, Chuan; Zhao, Guangyao; Jia, Jizeng; Kong, Xiuying

2015-01-01

NAC transcription factors play diverse roles in plant development and responses to abiotic stresses. However, the biological roles of NAC family members in wheat are not well understood. Here, we reported the isolation and functional characterization of a novel wheat TaNAC47 gene. TaNAC47 encoded protein, localizing in the nucleus, is able to bind to the ABRE cis-element and transactivate transcription in yeast, suggesting that it likely functions as a transcriptional activator. We also showed that TaNAC47 is differentially expressed in different tissues, and its expression was induced by the stress treatments of salt, cold, polyethylene glycol and exogenous abscisic acid. Furthermore, overexpression of TaNAC47 in Arabidopsis resulted in ABA hypersensitivity and enhancing tolerance of transgenic plants to drought, salt, and freezing stresses. Strikingly, overexpression of TaNAC47 was found to activate the expression of downstream genes and change several physiological indices that may enable transgenic plants to overcome unfavorable environments. Taken together, these results uncovered an important role of wheat TaNAC47 gene in response to ABA and abiotic stresses.

Quantifying Components of Soil Respiration and Their Response to Abiotic Factors in Two Typical Subtropical Forest Stands, Southwest China

PubMed Central

Yu, Lei; Wang, Yujie; Wang, Yunqi; Sun, Suqi; Liu, Liziyuan

2015-01-01

Separating the components of soil respiration and understanding the roles of abiotic factors at a temporal scale among different forest types are critical issues in forest ecosystem carbon cycling. This study quantified the proportions of autotrophic (R A) and heterotrophic (R H) in total soil (R T) respiration using trenching and litter removal. Field studies were conducted in two typical subtropical forest stands (broadleaf and needle leaf mixed forest; bamboo forest) at Jinyun Mountain, near the Three Georges Reservoir in southwest China, during the growing season (Apr.–Sep.) from 2010 to 2012. The effects of air temperature (AT), soil temperature (ST) and soil moisture (SM) at 6cm depth, solar radiation (SR), pH on components of soil respiration were analyzed. Results show that: 1) SR, AT, and ST exhibited a similar temporal trend. The observed abiotic factors showed slight interannual variability for the two forest stands. 2) The contributions of R H and R A to R T for broadleaf and needle leaf mixed forest were 73.25% and 26.75%, respectively, while those for bamboo forest were 89.02% and 10.98%, respectively; soil respiration peaked from June to July. In both stands, CO2 released from the decomposition of soil organic matter (SOM), the strongest contributor to R T, accounted for over 63% of R H. 3) AT and ST were significantly positively correlated with R T and its components (p<0.05), and were major factors affecting soil respiration. 4) Components of soil respiration were significantly different between two forest stands (p<0.05), indicating that vegetation types played a role in soil respiration and its components. PMID:25680112

[The relationship between abiotic factors and microbial activities of microbial eco-system in contaminated soil with petroleum hydrocarbons].

PubMed

Jia, Jian-li; Li, Guang-he; Zhong, Yi

2004-05-01

By means of the biostimulation and bioaugmentation in the micro-ecological environment of contaminated soil with petrochemical hydrocarbons, the biodegradation rates and mode of the contaminants were significantly improved. Based on the investigations carried out in some oilfields and petrochemical industrial area of Northern China, the relationship between the abiotic factors such as nutrient, pH, contaminants, water content, alkalinity, etc., and microbial activities was interpreted and identified in this paper. The results from the investigations and indoor and in-situ experiments conducted recent years indicated that the soils in the areas, to the extent, have been polluted by the different kinds of organic compounds composed of monoaromatic benzene, PAHs, chlorinated solvent, and alkanes, and the concentrations of the compounds mostly were elevated as compared to the background, with the highest 34,000 mg/kg dry soil. The column chromatography analysis results showed that the alkyl and aromatic compounds were accounted for more than 50% of the total hydrocarbon contents, which was readily degraded by degrading bacteria and improved the degrading microbe activities. The effective nitrogen and phosphorus encountered in the soil was less than 30 mg/kg dry soil and 10 mg/kg dry soil, only about 5% of total contents of them respectively. Based on the stoichiometric calculation and reasonable ratio of carbon to nutrient content regarding the biodegradation of organic compounds, the nutrient levels mainly composed of nitrogen and phosphorus in polluted soil as importantly limiting factors to degrading bacterial growth and activity were insufficient to the biodegradation of petrochemicals, and it is needed to add the nutrient for the bioremediation of contaminated soil. It is undoubted that the optimization of abiotic factors play significant role in increasing the microbial activity and improving the biodegradation rates.

Biotic and abiotic influences on abundance and distribution of nonnative Chinook salmon and native ESA-listed steelhead in the Wind River, Washington

USGS Publications Warehouse

Jezorek, Ian G.; Connolly, Patrick J.

2015-01-01

Biotic and abiotic factors influence fish populations and distributions. Concerns have been raised about the influence of hatchery fish on wild populations. Carson National Fish Hatchery produces spring Chinook salmon Oncorhynchus tshawytscha in the Wind River, Washington, and some spawn in the river. Managers were concerned that Chinook salmon could negatively affect wild steelhead O. mykiss and that a self-sustaining population of Chinook salmon may develop. Our objectives were to assess: 1) the distribution and populations of juvenile spring Chinook salmon and juvenile steelhead in the upper Wind River; 2) the influence of stream flow and of each population on the other; and 3) if Chinook salmon populations were self-sustaining. We snorkeled to determine distribution and abundance. Flow in the fall influenced upstream distribution and abundance of juvenile Chinook salmon. Juvenile Chinook salmon densities were consistently low (range 0.0 to 5.7 fish 100 m-2) and not influenced by number of spawners, winter flow magnitude, or steelhead abundance. Juvenile steelhead were distributed through the study section each year. Age-0 and age-1 steelhead densities (age-0 range: 0.04 to 37.0 fish 100 m-2; age-1 range: 0.02 to 6.21 fish 100 m-2) were consistently higher than for juvenile Chinook salmon. Steelhead spawner abundance positively influenced juvenile steelhead abundance. During this study, Chinook salmon in the Wind River appear to have had little effect on steelhead. Low juvenile Chinook salmon abundance and a lack of a spawner-to-juvenile relationship suggest Chinook salmon are not self-sustaining and potential for such a population is low under current conditions.

Ectopic Expression of Pumpkin NAC Transcription Factor CmNAC1 Improves Multiple Abiotic Stress Tolerance in Arabidopsis

PubMed Central

Cao, Haishun; Wang, Li; Nawaz, Muhammad A.; Niu, Mengliang; Sun, Jingyu; Xie, Junjun; Kong, Qiusheng; Huang, Yuan; Cheng, Fei; Bie, Zhilong

2017-01-01

Drought, cold and salinity are the major environmental stresses that limit agricultural productivity. NAC transcription factors regulate the stress response in plants. Pumpkin (Cucurbita moschata) is an important cucurbit vegetable crop and it has strong resistance to abiotic stress; however, the biological functions of stress-related NAC genes in this crop are largely unknown. This study reports the function of CmNAC1, a stress-responsive pumpkin NAC domain protein. The CmNAC1-GFP fusion protein was transiently expressed in tobacco leaves for subcellular localization analysis, and we found that CmNAC1 is localized in the nucleus. Transactivation assay in yeast cells revealed that CmNAC1 functions as a transcription activator, and its transactivation domain is located in the C-terminus. CmNAC1 was ubiquitously expressed in different organs, and its transcript was induced by salinity, cold, dehydration, H2O2, and abscisic acid (ABA) treatment. Furthermore, the ectopic expression (EE) of CmNAC1 in Arabidopsis led to ABA hypersensitivity and enhanced tolerance to salinity, drought and cold stress. In addition, five ABA-responsive elements were enriched in CmNAC1 promoter. The CmNAC1-EE plants exhibited different root architecture, leaf morphology, and significantly high concentration of ABA compared with WT Arabidopsis under normal conditions. Our results indicated that CmNAC1 is a critical factor in ABA signaling pathways and it can be utilized in transgenic breeding to improve the abiotic stress tolerance of crops. PMID:29234347

Soil moisture and biogeochemical factors influence the distribution of annual Bromus species

Treesearch

Jayne Belnap; John M. Stark; Benjamin M. Rau; Edith B. Allen; Susan Phillips

2016-01-01

Abiotic factors have a strong influence on where annual Bromus species are found. At the large regional scale, temperature and precipitation extremes determine the boundaries of Bromus occurrence. At the more local scale, soil characteristics and climate influence distribution, cover, and performance. In hot, dry, summer-rainfall-dominated deserts (Sonoran, Chihuahuan...

Namib Desert edaphic bacterial, fungal and archaeal communities assemble through deterministic processes but are influenced by different abiotic parameters.

PubMed

Johnson, Riegardt M; Ramond, Jean-Baptiste; Gunnigle, Eoin; Seely, Mary; Cowan, Don A

2017-03-01

The central Namib Desert is hyperarid, where limited plant growth ensures that biogeochemical processes are largely driven by microbial populations. Recent research has shown that niche partitioning is critically involved in the assembly of Namib Desert edaphic communities. However, these studies have mainly focussed on the Domain Bacteria. Using microbial community fingerprinting, we compared the assembly of the bacterial, fungal and archaeal populations of microbial communities across nine soil niches from four Namib Desert soil habitats (riverbed, dune, gravel plain and salt pan). Permutational multivariate analysis of variance indicated that the nine soil niches presented significantly different physicochemistries (R 2  = 0.8306, P ≤ 0.0001) and that bacterial, fungal and archaeal populations were soil niche specific (R 2  ≥ 0.64, P ≤ 0.001). However, the abiotic drivers of community structure were Domain-specific (P < 0.05), with P, clay and sand fraction, and NH 4 influencing bacterial, fungal and archaeal communities, respectively. Soil physicochemistry and soil niche explained over 50% of the variation in community structure, and communities displayed strong non-random patterns of co-occurrence. Taken together, these results demonstrate that in central Namib Desert soil microbial communities, assembly is principally driven by deterministic processes.

Identification and expression of the WRKY transcription factors of Carica papaya in response to abiotic and biotic stresses.

PubMed

Pan, Lin-Jie; Jiang, Ling

2014-03-01

The WRKY transcription factor (TF) plays a very important role in the response of plants to various abiotic and biotic stresses. A local papaya database was built according to the GenBank expressed sequence tag database using the BioEdit software. Fifty-two coding sequences of Carica papaya WRKY TFs were predicted using the tBLASTn tool. The phylogenetic tree of the WRKY proteins was classified. The expression profiles of 13 selected C. papaya WRKY TF genes under stress induction were constructed by quantitative real-time polymerase chain reaction. The expression levels of these WRKY genes in response to 3 abiotic and 2 biotic stresses were evaluated. TF807.3 and TF72.14 are upregulated by low temperature; TF807.3, TF43.76, TF12.199 and TF12.62 are involved in the response to drought stress; TF9.35, TF18.51, TF72.14 and TF12.199 is involved in response to wound; TF12.199, TF807.3, TF21.156 and TF18.51 was induced by PRSV pathogen; TF72.14 and TF43.76 are upregulated by SA. The regulated expression levels of above eight genes normalized against housekeeping gene actin were significant at probability of 0.01 levels. These WRKY TFs could be related to corresponding stress resistance and selected as the candidate genes, especially, the two genes TF807.3 and TF12.199, which were regulated notably by four stresses respectively. This study may provide useful information and candidate genes for the development of transgenic stress tolerant papaya varieties.

How arbuscular mycorrhizal fungi influence the defense system of sunflower during different abiotic stresses.

PubMed

Mayer, Zoltán; Duc, Nguyen Hong; Sasvári, Zita; Posta, Katalin

2017-12-01

The association between terrestrial plants and arbuscular mycorrhizal (AM) fungi is one of the most common and widespread mutualistic plant-fungi interaction. AM fungi are of beneficial effects on the water and nutrient uptake of plants and increase plant defense mechanisms to alleviate different stresses. The aim of this study was to determine the level of polyphenol oxidase (PPO), guaiacol peroxidase (POX) and glutathione S-transferase (GST) enzyme activities and to track the expression of glutathione S-transferase (GST) gene in plant-arbuscular mycorrhizal system under temperature- and mechanical stress conditions. Our results suggest that induced tolerance of mycorrhizal sunflower to high temperature may be attributed to the induction of GST, POX and PPO enzyme activities as well as to the elevated expression of GST. However, the degree of tolerance of the plant is significantly influenced by the age which is probably justified by the energy considerations.

Genome-wide identification and expression profile analysis of the NAC transcription factor family during abiotic and biotic stress in woodland strawberry

PubMed Central

Qi, Yanxiang; Liu, Xiaomei; Pu, Jinji

2018-01-01

The NAC transcription factors involved plant development and response to various stress stimuli. However, little information is available concerning the NAC family in the woodland strawberry. Herein, 37 NAC genes were identified from the woodland strawberry genome and were classified into 13 groups based on phylogenetic analysis. And further analyses of gene structure and conserved motifs showed closer relationship of them in every subgroup. Quantitative real-time PCR evaluation different tissues revealed distinct spatial expression profiles of the FvNAC genes. The comprehensive expression of FvNAC genes revealed under abiotic stress (cold, heat, drought, salt), signal molecule treatments (H2O2, ABA, melatonin, rapamycin), biotic stress (Colletotrichum gloeosporioides and Ralstonia solanacearum). Expression profiles derived from quantitative real-time PCR suggested that 5 FvNAC genes responded dramatically to the various abiotic and biotic stresses, indicating their contribution to abiotic and biotic stresses resistance in woodland strawberry. Interestingly, FvNAC genes showed greater extent responded to the cold treatment than other abiotic stress, and H2O2 exhibited a greater response than ABA, melatonin, and rapamycin. For biotic stresses, 3 FvNAC genes were up-regulated during infection with C. gloeosporioides, while 6 FvNAC genes were down-regulated during infection with R. solanacearum. In conclusion, this study identified candidate FvNAC genes to be used for the genetic improvement of abiotic and biotic stress tolerance in woodland strawberry. PMID:29897926

A Wheat WRKY Transcription Factor TaWRKY10 Confers Tolerance to Multiple Abiotic Stresses in Transgenic Tobacco

PubMed Central

Chen, Liulin; Wang, Xiatian; Ma, Hui; Hu, Wei; Yao, Ningcong; Feng, Ying; Chai, Ruihong; Yang, Guangxiao; He, Guangyuan

2013-01-01

WRKY transcription factors are reported to be involved in defense regulation, stress response and plant growth and development. However, the precise role of WRKY transcription factors in abiotic stress tolerance is not completely understood, especially in crops. In this study, we identified and cloned 10 WRKY genes from genome of wheat (Triticum aestivum L.). TaWRKY10, a gene induced by multiple stresses, was selected for further investigation. TaWRKY10 was upregulated by treatment with polyethylene glycol, NaCl, cold and H2O2. Result of Southern blot indicates that the wheat genome contains three copies of TaWRKY10. The TaWRKY10 protein is localized in the nucleus and functions as a transcriptional activator. Overexpression of TaWRKY10 in tobacco (Nicotiana tabacum L.) resulted in enhanced drought and salt stress tolerance, mainly demonstrated by the transgenic plants exhibiting of increased germination rate, root length, survival rate, and relative water content under these stress conditions. Further investigation showed that transgenic plants also retained higher proline and soluble sugar contents, and lower reactive oxygen species and malonaldehyde contents. Moreover, overexpression of the TaWRKY10 regulated the expression of a series of stress related genes. Taken together, our results indicate that TaWRKY10 functions as a positive factor under drought and salt stresses by regulating the osmotic balance, ROS scavenging and transcription of stress related genes. PMID:23762295

A wheat WRKY transcription factor TaWRKY10 confers tolerance to multiple abiotic stresses in transgenic tobacco.

PubMed

Wang, Chen; Deng, Pengyi; Chen, Liulin; Wang, Xiatian; Ma, Hui; Hu, Wei; Yao, Ningcong; Feng, Ying; Chai, Ruihong; Yang, Guangxiao; He, Guangyuan

2013-01-01

WRKY transcription factors are reported to be involved in defense regulation, stress response and plant growth and development. However, the precise role of WRKY transcription factors in abiotic stress tolerance is not completely understood, especially in crops. In this study, we identified and cloned 10 WRKY genes from genome of wheat (Triticum aestivum L.). TaWRKY10, a gene induced by multiple stresses, was selected for further investigation. TaWRKY10 was upregulated by treatment with polyethylene glycol, NaCl, cold and H2O2. Result of Southern blot indicates that the wheat genome contains three copies of TaWRKY10. The TaWRKY10 protein is localized in the nucleus and functions as a transcriptional activator. Overexpression of TaWRKY10 in tobacco (Nicotiana tabacum L.) resulted in enhanced drought and salt stress tolerance, mainly demonstrated by the transgenic plants exhibiting of increased germination rate, root length, survival rate, and relative water content under these stress conditions. Further investigation showed that transgenic plants also retained higher proline and soluble sugar contents, and lower reactive oxygen species and malonaldehyde contents. Moreover, overexpression of the TaWRKY10 regulated the expression of a series of stress related genes. Taken together, our results indicate that TaWRKY10 functions as a positive factor under drought and salt stresses by regulating the osmotic balance, ROS scavenging and transcription of stress related genes.

Impact of abiotic factors on development of the community of arbuscular mycorrhizal fungi in the soil: a Review

NASA Astrophysics Data System (ADS)

Jamiołkowska, Agnieszka; Księżniak, Andrzej; Gałązka, Anna; Hetman, Beata; Kopacki, Marek; Skwaryło-Bednarz, Barbara

2018-01-01

Arbuscular mycorrhizal fungi inhabiting soil play an important role for vascular plants. Interaction between arbuscular mycorrhizal fungi, plants and soil microorganisms leads to many mutual advantages. However, the effectiveness of mycorrhizal fungi depends not only on biotic, but also abiotic factors such as physico-chemical properties of the soil, availability of water and biogenic elements, agricultural practices, and climatic conditions. First of all, it is important to adapt the arbuscular mycorrhizal fungi species to changing environmental conditions. The compactness of the soil and its structure have a huge impact on its biological activity. Soil pH reaction has a substantial impact on the mobility of ions in soil dilutions and their uptake by plants and soil microflora. Water excess can be a factor negatively affecting arbuscular mycorrhizal fungi because these microorganisms are sensitive to a lower availability of oxygen. Mechanical cultivation of the soil has a marginal impact on the arbuscular mycorrhizal fungi spores. However, soil translocation can cause changes to the population of the arbuscular mycorrhizal fungi abundance in the soil profile. The geographical location and topographic differentiation of cultivated soils, as well as the variability of climatic factors affect the population of the arbuscular mycorrhizal fungi in the soils and their symbiotic activity.

Invasion biology in non-free-living species: interactions between abiotic (climatic) and biotic (host availability) factors in geographical space in crayfish commensals (Ostracoda, Entocytheridae)

PubMed Central

Mestre, Alexandre; Aguilar-Alberola, Josep A; Baldry, David; Balkis, Husamettin; Ellis, Adam; Gil-Delgado, Jose A; Grabow, Karsten; Klobučar, Göran; Kouba, Antonín; Maguire, Ivana; Martens, Andreas; Mülayim, Ayşegül; Rueda, Juan; Scharf, Burkhard; Soes, Menno; S Monrós, Juan; Mesquita-Joanes, Francesc

2013-01-01

In invasion processes, both abiotic and biotic factors are considered essential, but the latter are usually disregarded when modeling the potential spread of exotic species. In the framework of set theory, interactions between biotic (B), abiotic (A), and movement-related (M) factors in the geographical space can be hypothesized with BAM diagrams and tested using ecological niche models (ENMs) to estimate A and B areas. The main aim of our survey was to evaluate the interactions between abiotic (climatic) and biotic (host availability) factors in geographical space for exotic symbionts (i.e., non-free-living species), using ENM techniques combined with a BAM framework and using exotic Entocytheridae (Ostracoda) found in Europe as model organisms. We carried out an extensive survey to evaluate the distribution of entocytherids hosted by crayfish in Europe by checking 94 European localities and 12 crayfish species. Both exotic entocytherid species found, Ankylocythere sinuosa and Uncinocythere occidentalis, were widely distributed in W Europe living on the exotic crayfish species Procambarus clarkii and Pacifastacus leniusculus, respectively. No entocytherids were observed in the remaining crayfish species. The suitable area for A. sinuosa was mainly restricted by its own limitations to minimum temperatures in W and N Europe and precipitation seasonality in circum-Mediterranean areas. Uncinocythere occidentalis was mostly restricted by host availability in circum-Mediterranean regions due to limitations of P. leniusculus to higher precipitation seasonality and maximum temperatures. The combination of ENMs with set theory allows studying the invasive biology of symbionts and provides clues about biogeographic barriers due to abiotic or biotic factors limiting the expansion of the symbiont in different regions of the invasive range. The relative importance of abiotic and biotic factors on geographical space can then be assessed and applied in conservation plans. This

Invasion biology in non-free-living species: interactions between abiotic (climatic) and biotic (host availability) factors in geographical space in crayfish commensals (Ostracoda, Entocytheridae).

PubMed

Mestre, Alexandre; Aguilar-Alberola, Josep A; Baldry, David; Balkis, Husamettin; Ellis, Adam; Gil-Delgado, Jose A; Grabow, Karsten; Klobučar, Göran; Kouba, Antonín; Maguire, Ivana; Martens, Andreas; Mülayim, Ayşegül; Rueda, Juan; Scharf, Burkhard; Soes, Menno; S Monrós, Juan; Mesquita-Joanes, Francesc

2013-12-01

In invasion processes, both abiotic and biotic factors are considered essential, but the latter are usually disregarded when modeling the potential spread of exotic species. In the framework of set theory, interactions between biotic (B), abiotic (A), and movement-related (M) factors in the geographical space can be hypothesized with BAM diagrams and tested using ecological niche models (ENMs) to estimate A and B areas. The main aim of our survey was to evaluate the interactions between abiotic (climatic) and biotic (host availability) factors in geographical space for exotic symbionts (i.e., non-free-living species), using ENM techniques combined with a BAM framework and using exotic Entocytheridae (Ostracoda) found in Europe as model organisms. We carried out an extensive survey to evaluate the distribution of entocytherids hosted by crayfish in Europe by checking 94 European localities and 12 crayfish species. Both exotic entocytherid species found, Ankylocythere sinuosa and Uncinocythere occidentalis, were widely distributed in W Europe living on the exotic crayfish species Procambarus clarkii and Pacifastacus leniusculus, respectively. No entocytherids were observed in the remaining crayfish species. The suitable area for A. sinuosa was mainly restricted by its own limitations to minimum temperatures in W and N Europe and precipitation seasonality in circum-Mediterranean areas. Uncinocythere occidentalis was mostly restricted by host availability in circum-Mediterranean regions due to limitations of P. leniusculus to higher precipitation seasonality and maximum temperatures. The combination of ENMs with set theory allows studying the invasive biology of symbionts and provides clues about biogeographic barriers due to abiotic or biotic factors limiting the expansion of the symbiont in different regions of the invasive range. The relative importance of abiotic and biotic factors on geographical space can then be assessed and applied in conservation plans. This

Abiotic Factors Affecting Benthic Invertebrate Biomass and Community Structure in a Fourth-Order Rocky Mountain Watershed

NASA Astrophysics Data System (ADS)

Chanat, J. G.; Clements, W. H.; MacDonald, L. H.

2005-05-01

The potential ecological impact of excess streambed sediment resulting from forest management activities is a persistent concern for land managers. This study examined the relationship between streambed sediment, along with other site- and reach-scale abiotic factors, and benthic macroinvertebrate community structure in a 272 km2 basin in the Colorado Front Range. Physical habitat parameters and invertebrates were sampled in late summer at 68 sites located in sixteen stream reaches. Invertebrate data were used to formulate twenty indices of community structure. Multiple regression identified site-level substrate particle size as the most important predictor of six indices, including total density (R2 = 0.22), biomass (R2 = 0.17), and taxa richness (R2 = 0.32). All of the remaining fourteen indices were most strongly predicted by reach-level variables, including discharge (percent shredders, R2 = 0.24; Plecoptera density, R2 = 0.29), and elevation (percent collector-filterers, R2 = 0.28; Trichoptera density, R2 = 0.37). Although the sites represented a wide range of substrate composition and embeddedness, no physical variable associated with fine sediment appeared as a strong predictor of any of the twenty indices. Thus, sediment is not among the most important factors associated with site-to-site variability of benthic community structure in this relatively pristine watershed.

[Biotic and abiotic factors that affect the quality of Schinopsis balansae Engl. and Aspidosperma quebracho-blanco Schltdl. seeds].

PubMed

Alzugaray, Claudia; Carnevale, Nélida J; Salinas, Adriana R; Pioli, Rosanna

2007-06-01

Aspidosperma quebracho-blanco (white quebracho) and Schinopsis balansae (red quebracho) are distinctive trees of the South American Park in Argentina. Quebrachos are found in forests that have been exploited very intensively. The object of this work was the identification of biotic and abiotic factors specially fungal pathogen that affect the quality of both species and its relation with germination. Seeds where evaluated through germination test and the percentage of the incidence of fungal agents in two different years of harvest was determined. In S. balansae the germination rate was 77% and of 27% in 2000 and 2001 harvests, respectively. Associations fungi-germination were found in 2001 for Alternaria spp., Curvularia spp., and Fusarium spp., showing an coefficient of correlation = -0.84; -0.85 and -0.73 (p < 0.00004), respectively. A high percentage of vane seeds (55%) was also found in 2001 harvest, due to adverse environmental factors, specifically higher precipitations during flowering. In A. quebracho-blanco seeds, the germination rate was 50% and 90% in 2000 and 2003 respectively, with a 42% of immature seeds in 2000 harvest that was associated to high precipitations and high temperatures during flowering and ripping of fruits. The incidence of pathogens was low and did not have association to germination.

Seasonal biotic and abiotic factors affecting hunting strategy in free-living Saharan sand vipers, Cerastes vipera.

PubMed

Horesh, Sefi J A; Sivan, Jaim; Rosenstrauch, Avi; Tesler, Itay; Degen, A Allan; Kam, Michael

2017-02-01

Sit-and-wait ambushing and active hunting are two strategies used by predators to capture prey. In snakes, hunting strategy is conserved phylogenetically; most species employ only one strategy. Active hunters encounter and capture more prey but invest more energy in hunting and have higher risks of being predated. This trade-off is important to small predators. The small Cerastes vipera employs both modes of hunting, which is unlike most viperids which use only sit-and wait ambushing. This species hibernates in October and emerges in April. Energy intake should be high prior to hibernation to overcome the non-feeding hibernation period and for reproduction on their emergence. We predicted that more individuals would hunt actively towards hibernation and an abiotic factor would trigger this response. Furthermore, since more energy is required for active hunting, we predicted that snakes in good body condition would use active hunting to a greater extent than snakes in poor body condition. To test our predictions, we tracked free-living snakes year round and determined their hunting strategy, estimated their body condition index (BCI), and calculated circannual parameters of day length as environmental cues known to affect animal behaviour. Two novel findings emerged in this study, namely, hunting strategy was affected significantly by 1) the circannual change in day length and 2) by BCI. The proportion of active hunters increased from 5% in April to over 30% in October and BCI of active foragers was higher than that of sit-and-wait foragers and, therefore, our predictions were supported. The entrainment between the proportion of active hunting and the abiotic factor is indicative of an adaptive function for choosing a hunting strategy. A trend was evident among life stages. When all life stages were present (September-October), the proportion of active foragers increased with age: 0.0% among neonates, 18.2% among juveniles and 31.4% among adults. We concluded that

Effects of abiotic factors on the nanostructure of diatom frustules-ranges and variability.

PubMed

Su, Yanyan; Lundholm, Nina; Ellegaard, Marianne

2018-05-26

The intricate patterning of diatom silica frustules at nanometer-to-micrometer scales makes them of interest for a wide range of industrial applications. For some of these applications, a specific size range in nanostructure is required and may be achieved by selecting species with the desired properties. However, as all biological materials, diatom frustules exhibit variability in their morphological parameters and this variability can to some extent be affected and controlled by environmental conditions. In this review, we explore the effects of different environmental factors including salinity, heavy metals, temperature, pH, extracellular Si(OH) 4 or Ge(OH) 4 concentration, light regime, UV irradiance, long-term cultivation, and biotic factors on the nanostructure of diatom frustules. This compilation of studies illustrates that it is possible to affect the nanostructure of diatom frustules in vivo by controlling different environmental factors as well as by direct chemical modification of frustules. We compare these methods and present examples of how these changes affect the range of variability as well as comparing the magnitude of size changes of the most promising methods.

Factors influencing wound dehiscence.

PubMed

Riou, J P; Cohen, J R; Johnson, H

1992-03-01

Thirty-one abdominal fascial wound dehiscences occurred in 2,761 patients undergoing major abdominal surgery during a 5-year period (1%). Twenty-two specific local and systemic risk factors were analyzed and compared with the risk factors of a control group of 38 patients undergoing similar procedures without dehiscence. Through multivariate analysis, each factor was assessed as an independent statistical variable. Significant factors (p less than 0.05) were found to include age over 65, wound infection, pulmonary disease, hemodynamic instability, and ostomies in the incision. Additional systemic risk factors that were found to be significant included hypoproteinemia, systemic infection, obesity, uremia, hyperalimentation, malignancy, ascites, steroid use, and hypertension. Risk factors not found to be important independent variables included sex, type of incision, type of closure, foreign body in the wound, anemia, jaundice, and diabetes. When dehiscence and control groups were combined, 30% of patients with at least five significant risk factors developed dehiscence, and all the patients with more than eight risk factors developed a wound dehiscence. There was an overall mortality of 29%, which was directly related to the number of significant risk factors. The co-existence of 9 risk factors portended death in one third of the patients, and all the patients with more than 10 risk factors died.

Abiotic and biotic factors associated with the presence of Anopheles arabiensis immatures and their abundance in naturally occurring and man-made aquatic habitats

PubMed Central

2012-01-01

Background Anopheles arabiensis (Diptera: Culicidae) is a potential malaria vector commonly present at low altitudes in remote areas in Reunion Island. Little attention has been paid to the environmental conditions driving larval development and abundance patterns in potential habitats. Two field surveys were designed to determine whether factors that discriminate between aquatic habitats with and without An. arabiensis larvae also drive larval abundance, comparatively in man-made and naturally occurring habitats. Methods In an initial preliminary survey, a representative sample of aquatic habitats that would be amenable to an intensive long-term study were selected and divided into positive and negative sites based on the presence or absence of Anopheles arabiensis larvae. Subsequently, a second survey was prompted to gain a better understanding of biotic and abiotic drivers of larval abundance, comparatively in man-made and naturally occurring habitats in the two studied locations. In both surveys, weekly sampling was performed to record mosquito species composition and larval density within individual habitats, as well as in situ biological characteristics and physico-chemical properties. Results Whilst virtually any stagnant water body could be a potential breeding ground for An. arabiensis, habitats occupied by their immatures had different structural and biological characteristics when compared to those where larvae were absent. Larval occurrence seemed to be influenced by flow velocity, macrofauna diversity and predation pressure. Interestingly, the relative abundance of larvae in man-made habitats (average: 0.55 larvae per dip, 95%CI [0.3–0.7]) was significantly lower than that recorded in naturally occurring ones (0.74, 95%CI [0.5–0.8]). Such differences may be accounted for in part by varying pressures that could be linked to a specific habitat. Conclusions If the larval ecology of An. arabiensis is in general very complex and factors affecting

Identification and expression of C2H2 transcription factor genes in Carica papaya under abiotic and biotic stresses.

PubMed

Jiang, Ling; Pan, Lin-jie

2012-06-01

C2H2 proteins belong to a group of transcription factors (TFs) existing as a superfamily that plays important roles in defense responses and various other physiological processes in plants. The present study aimed to screen for and identify C2H2 proteins associated with defense responses to abiotic and biotic stresses in Carica papaya L. Data were collected for 47,483 papaya-expressed sequence tags (ESTs). The full-length cDNA nucleotide sequences of 87 C2H2 proteins were predicated by BioEdit. All 91 C2H2 proteins were aligned, and a phylogenetic tree was constructed using DNAman. The expression levels of 42 C2H2 were analyzed under conditions of salt stress by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Methyl jasmonate treatment rapidly upregulated ZF(23.4) and ZF(30,912.1) by 18.6- and 21.7-fold, respectively. ZF(1.3), ZF(138.44), ZF(94.49), ZF(29.160), and ZF(20.206) were found to be downregulated after low temperature treatment at very significant levels (p < 0.01). ZF(23.4), ZF(161.1), and ZF(30,912.1) were upregulated while ZF1.3, ZF(158.1), ZF(249.5), ZF(138.44), ZF(94.49), ZF(29.160), and ZF(20.206) were significantly downregulated by Spermine treatment. ZF(23.4) was upregulated while ZF(1.3), ZF(249.5), ZF(94.94), ZF(29.160), ZF(138.44), and ZF(20.206) were significantly repressed after SA treatment. ZF(23.4) and ZF(30,912.1) were significantly upregulated after sap inoculation with papaya ringspot virus pathogen. ZF(30,912.1) was subcellularly localized in the nucleus by a transgenic fusion of pBS-ZF(30,912.1)-GFP into the protoplast of papaya. The results of the present study showed that ZF(30,912.1) could be an important TF that mediates responses to abiotic and biotic stresses in papaya.

Combined effects of Corexit EC 9500A with secondary abiotic and biotic factors in the rotifer Brachionus plicatilis.

PubMed

Williams, Michael B; Powell, Mickie L; Watts, Stephen A

2016-10-01

We examined lethality and behavioral effects of Corexit EC 9500A (C-9500A) exposure on the model marine zooplankton Brachionus plicatilis singularly and in combination with abiotic and biotic factors. C-9500A exposure at standard husbandry conditions (17.5ppt, 24°C, 200 rotifer*mL(-1) density) identified the 24h median lethal concentration, by Probit analysis, to be 107ppm for cultured B. plicatilis. Rotifers surviving exposure to higher concentrations (100 and 150ppm) exhibited a decreased swimming velocity and a reduced net to gross movement ratio. Significant interaction between C-9500A exposure and temperature or salinity was observed. Upper thermal range was reduced and maximal salinity stress was seen as ca. 25ppt. Increased or decreased nutritional availability over the exposure period did not significantly alter mortality of B. plicatilis populations at the concentrations tested. Results from this study may be useful for predicting possible outcomes on marine zooplankton following dispersant application under diverse natural conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

Evolution analysis of Dof transcription factor family and their expression in response to multiple abiotic stresses in Malus domestica.

PubMed

Zhang, Zhengrong; Yuan, Li; Liu, Xin; Chen, Xuesen; Wang, Xiaoyun

2018-01-10

As a family of transcription factors, DNA binding with one figure (Dof) proteins play important roles in various biological processes in plants. Here, a total of 60 putative apple (Malus domestica) Dof genes (MdDof) were identified and mapped to different chromosomes. Chromosomal distribution and synteny analysis indicated that the expansion of the MdDof genes came primarily from segmental and duplication events, and from whole genome duplication, which lead to more Dof members in apples than in other plants. All 60 MdDof genes were classified into thirteen groups, according to multiple sequence alignment and the phylogenetic tree constructed of Dof genes from apple, peach (Prunus persica), Arabidopsis and rice. Within each group, the members shared a similar exon/intron and motif compositions, although the sizes of the MdDof genes and encoding proteins were quite different. Several Dof genes from the apple and peach were identified to be homologues based on their close synteny relationship, which suggested that these genes bear similar functions. Half of the MdDof genes were randomly selected to determine their responses to different stresses. The majority of MdDof genes were quite sensitive to PEG, NaCl, cold and exogenous ABA treatment. Our results suggested that MdDof family members may play important roles in plant tolerance to abiotic stress. Copyright © 2017 Elsevier B.V. All rights reserved.

Cork Oak Vulnerability to Fire: The Role of Bark Harvesting, Tree Characteristics and Abiotic Factors

PubMed Central

Catry, Filipe X.; Moreira, Francisco; Pausas, Juli G.; Fernandes, Paulo M.; Rego, Francisco; Cardillo, Enrique; Curt, Thomas

2012-01-01

Forest ecosystems where periodical tree bark harvesting is a major economic activity may be particularly vulnerable to disturbances such as fire, since debarking usually reduces tree vigour and protection against external agents. In this paper we asked how cork oak Quercus suber trees respond after wildfires and, in particular, how bark harvesting affects post-fire tree survival and resprouting. We gathered data from 22 wildfires (4585 trees) that occurred in three southern European countries (Portugal, Spain and France), covering a wide range of conditions characteristic of Q. suber ecosystems. Post-fire tree responses (tree mortality, stem mortality and crown resprouting) were examined in relation to management and ecological factors using generalized linear mixed-effects models. Results showed that bark thickness and bark harvesting are major factors affecting resistance of Q. suber to fire. Fire vulnerability was higher for trees with thin bark (young or recently debarked individuals) and decreased with increasing bark thickness until cork was 3–4 cm thick. This bark thickness corresponds to the moment when exploited trees are debarked again, meaning that exploited trees are vulnerable to fire during a longer period. Exploited trees were also more likely to be top-killed than unexploited trees, even for the same bark thickness. Additionally, vulnerability to fire increased with burn severity and with tree diameter, and was higher in trees burned in early summer or located in drier south-facing aspects. We provided tree response models useful to help estimating the impact of fire and to support management decisions. The results suggested that an appropriate management of surface fuels and changes in the bark harvesting regime (e.g. debarking coexisting trees in different years or increasing the harvesting cycle) would decrease vulnerability to fire and contribute to the conservation of cork oak ecosystems. PMID:22787521

Controls of Evapotranspiration and CO2 Fluxes from Scots Pine by Surface Conductance and Abiotic Factors

PubMed Central

Zha, Tianshan; Li, Chunyi; Kellomäki, Seppo; Peltola, Heli; Wang, Kai-Yun; Zhang, Yuqing

2013-01-01

Evapotranspiration (E) and CO2 flux (Fc) in the growing season of an unusual dry year were measured continuously over a Scots pine forest in eastern Finland, by eddy covariance techniques. The aims were to gain an understanding of their biological and environmental control processes. As a result, there were obvious diurnal and seasonal changes in E, Fc, surface conductance (gc), and decoupling coefficient (Ω), showing similar trends to those in radiation (PAR) and vapour pressure deficit (δ). The maximum mean daily values (24-h average) for E, Fc, gc, and Ω were 1.78 mmol m−2 s−1, −11.18 µmol m−2 s−1, 6.27 mm s−1, and 0.31, respectively, with seasonal averages of 0.71 mmol m−2 s−1, −4.61 µmol m−2 s−1, 3.3 mm s−1, and 0.16. E and Fc were controlled by combined biological and environmental variables. There was curvilinear dependence of E on gc and Fc on gc. Among the environmental variables, PAR was the most important factor having a positive linear relationship to E and curvilinear relationship to Fc, while vapour pressure deficit was the most important environmental factor affecting gc. Water use efficiency was slightly higher in the dry season, with mean monthly values ranging from 6.67 to 7.48 μmol CO2 (mmol H2O)−1 and a seasonal average of 7.06 μmol CO2 (μmol H2O)−1. Low Ω and its close positive relationship with gc indicate that evapotranspiration was sensitive to surface conductance. Mid summer drought reduced surface conductance and decoupling coefficient, suggesting a more biotic control of evapotranspiration and a physiological acclimation to dry air. Surface conductance remained low and constant under dry condition, supporting that a constant value of surface constant can be used for modelling transpiration under drought condition. PMID:23894401

Controls of evapotranspiration and CO2 fluxes from scots pine by surface conductance and abiotic factors.

PubMed

Zha, Tianshan; Li, Chunyi; Kellomäki, Seppo; Peltola, Heli; Wang, Kai-Yun; Zhang, Yuqing

2013-01-01

Evapotranspiration (E) and CO2 flux (Fc ) in the growing season of an unusual dry year were measured continuously over a Scots pine forest in eastern Finland, by eddy covariance techniques. The aims were to gain an understanding of their biological and environmental control processes. As a result, there were obvious diurnal and seasonal changes in E, Fc , surface conductance (gc ), and decoupling coefficient (Ω), showing similar trends to those in radiation (PAR) and vapour pressure deficit (δ). The maximum mean daily values (24-h average) for E, Fc , gc , and Ω were 1.78 mmol m(-2) s(-1), -11.18 µmol m(-2) s(-1), 6.27 mm s(-1), and 0.31, respectively, with seasonal averages of 0.71 mmol m(-2) s(-1), -4.61 µmol m(-2) s(-1), 3.3 mm s(-1), and 0.16. E and Fc were controlled by combined biological and environmental variables. There was curvilinear dependence of E on gc and Fc on gc . Among the environmental variables, PAR was the most important factor having a positive linear relationship to E and curvilinear relationship to Fc , while vapour pressure deficit was the most important environmental factor affecting gc . Water use efficiency was slightly higher in the dry season, with mean monthly values ranging from 6.67 to 7.48 μmol CO2 (mmol H2O)(-1) and a seasonal average of 7.06 μmol CO2 (μmol H2O)(-1). Low Ω and its close positive relationship with gc indicate that evapotranspiration was sensitive to surface conductance. Mid summer drought reduced surface conductance and decoupling coefficient, suggesting a more biotic control of evapotranspiration and a physiological acclimation to dry air. Surface conductance remained low and constant under dry condition, supporting that a constant value of surface constant can be used for modelling transpiration under drought condition.

Factors influencing plant invasiveness

Treesearch

Yvette Ortega; Dean Pearson

2009-01-01

Invasiveness of spotted knapweed and biological control agents. Dean and Yvette are examining the influence of drought on the invasiveness of spotted knapweed (Centaurea maculosa) and its susceptibility to herbivory by biological control agents. In collaboration with the University of Montana and Forest Health Protection, researchers have constructed 150...

Interplay between abiotic factors and species assemblages mediated by the ecosystem engineer Sabellaria alveolata (Annelida: Polychaeta)

NASA Astrophysics Data System (ADS)

Jones, Auriane G.; Dubois, Stanislas F.; Desroy, Nicolas; Fournier, Jérôme

2018-01-01

, associated and control sediment assemblages. These two parameters are under the ecosystem engineer's influence stressing its importance in structuring benthic macrofauna. Furthermore, in late summer but not in late winter, presence/absence and abundance-based beta diversity were positively correlated to our disturbance proxy (mud content) a tendency driven by a species replacement and a rise in the associated fauna density. Our first set of results highlight the importance of S. alveolata reefs as benthic primary production enhancers via their physical structure and their biological activity. The results obtained using beta diversity indices emphasize the importance of recruitment in structuring the reef's macrofauna and - paradoxically - the ecological value of S. alveolata degraded forms as biodiversity and recruitment promoters.

Ostreopsis cf. ovata dynamics in the NW Mediterranean Sea in relation to biotic and abiotic factors.

PubMed

Carnicer, Olga; Guallar, Carles; Andree, Karl B; Diogène, Jorge; Fernández-Tejedor, Margarita

2015-11-01

An expansion of the distribution of Ostreopsis cf. ovata, a dinoflagellate which produces palytoxin-like compounds, has been reported in recent years. Economical and social interests are affected by blooms, as they are responsible for respiratory and skin problems in humans and may cause damage to marine organisms. In order to identify the most influential environmental factors that trigger proliferations of O. cf. ovata in the area of the adjacent shallow rocky coast of the Ebro Delta (NW Mediterranean Sea) a three-year survey was performed on the metaphytic microalgae community growing on the macrophytes Jania rubens and Corallina elongata. Small-size diatoms were more abundant than dinoflagellates; O. cf. ovata was identified as the only species present from the genus. Seawater temperature was the primary driver defining the ecological niche of O. cf. ovata. Freshwater and groundwater fluxes were more pronounced in southern than in northern sites, which may have resulted in a distinct O. cf. ovata spatial distribution, with the highest records of abundance and more frequent blooms in the north. In consequence, negative correlations between the abundance of O. cf. ovata and nitrate concentrations and significant positive correlation with salinity were observed. The temporal pattern of O. cf. ovata dynamics from mid-July to early-November is probably due to the fact that this species is observed only above a certain threshold temperature of seawater. Metaphytic cells of O. cf. ovata were smaller in the northern site than in the south, possibly as a result of an increase in cell division, coinciding with higher abundance, and this could be an indicator of favorable conditions. Toxicity in planktonic cells was negatively correlated with cell abundance in the water column, achieving maximum concentrations of 25pg. PLTX eqcell(-1). Copyright © 2015 Elsevier Inc. All rights reserved.

Ostreopsis cf. ovata dynamics in the NW Mediterranean Sea in relation to biotic and abiotic factors

SciTech Connect

Carnicer, Olga; Guallar, Carles; IFREMER, DYNECO-PELAGOS Centre de Brest, Pointe du Diable BP70, 29280 Plouzane

2015-11-15

An expansion of the distribution of Ostreopsis cf. ovata, a dinoflagellate which produces palytoxin-like compounds, has been reported in recent years. Economical and social interests are affected by blooms, as they are responsible for respiratory and skin problems in humans and may cause damage to marine organisms. In order to identify the most influential environmental factors that trigger proliferations of O. cf. ovata in the area of the adjacent shallow rocky coast of the Ebro Delta (NW Mediterranean Sea) a three-year survey was performed on the metaphytic microalgae community growing on the macrophytes Jania rubens and Corallina elongata. Small-size diatomsmore » were more abundant than dinoflagellates; O. cf. ovata was identified as the only species present from the genus. Seawater temperature was the primary driver defining the ecological niche of O. cf. ovata. Freshwater and groundwater fluxes were more pronounced in southern than in northern sites, which may have resulted in a distinct O. cf. ovata spatial distribution, with the highest records of abundance and more frequent blooms in the north. In consequence, negative correlations between the abundance of O. cf. ovata and nitrate concentrations and significant positive correlation with salinity were observed. The temporal pattern of O. cf. ovata dynamics from mid-July to early-November is probably due to the fact that this species is observed only above a certain threshold temperature of seawater. Metaphytic cells of O. cf. ovata were smaller in the northern site than in the south, possibly as a result of an increase in cell division, coinciding with higher abundance, and this could be an indicator of favorable conditions. Toxicity in planktonic cells was negatively correlated with cell abundance in the water column, achieving maximum concentrations of 25 pg. PLTX eq cell{sup −1}. - Highlights: • Presence of a single Ostreopsis genotype in confirmed through qPCR. • Temperature confirmed as the

Interactive Effects of UV-B Light with Abiotic Factors on Plant Growth and Chemistry, and Their Consequences for Defense against Arthropod Herbivores

PubMed Central

Escobar-Bravo, Rocio; Klinkhamer, Peter G. L.; Leiss, Kirsten A.

2017-01-01

Ultraviolet-B (UV-B) light plays a crucial role in plant–herbivorous arthropods interactions by inducing changes in constitutive and inducible plant defenses. In particular, constitutive defenses can be modulated by UV-B-induced photomorphogenic responses and changes in the plant metabolome. In accordance, the prospective use of UV-B light as a tool to increase plant protection in agricultural practice has gained increasing interest. Changes in the environmental conditions might, however, modulate the UV-B -induced plant responses. While in some cases plant responses to UV-B can increase adaptation to changes in certain abiotic factors, UV-B-induced responses might be also antagonized by the changing environment. The outcome of these interactions might have a great influence on how plants interact with their enemies, e.g., herbivorous arthropods. Here, we provide a review on the interactive effects of UV-B and light quantity and quality, increased temperature and drought stress on plant biochemistry, and we discuss the implications of the outcome of these interactions for plant resistance to arthropod pests. PMID:28303147

Factors influencing donor return.

PubMed

Schlumpf, Karen S; Glynn, Simone A; Schreiber, George B; Wright, David J; Randolph Steele, Whitney; Tu, Yongling; Hermansen, Sigurd; Higgins, Martha J; Garratty, George; Murphy, Edward L

2008-02-01

To predict future blood donation behavior and improve donor retention, it is important to understand the determinants of donor return. A self-administered questionnaire was completed in 2003 by 7905 current donors. With data mining methods, all factors measured by the survey were ranked as possible predictors of actual return within 12 months. Significant factors were analyzed with logistic regression to determine predictors of intention and of actual return. Younger and minority donors were less likely to return in 12 months. Predictors of donor return were higher prior donation frequency, higher intention to return, a convenient place to donate, and having a good donation experience. Most factors associated with actual donor return were also associated with a high intention to return. Although not significant for actual return, feeling a responsibility to help others, higher empathetic concern, and a feeling that being a blood donor means more than just donating blood were related to high intention to return. Prior donation frequency, intention to return, donation experience, and having a convenient location appear to significantly predict donor return. Clearly, donor behavior is dependent on more than one factor alone. Altruistic behavior, empathy, and social responsibility items did not enter our model to predict actual return. A donor's stated intention to give again is positively related to actual return and, while not a perfect measure, might be a useful proxy when donor return cannot be determined.

The abiotic environment of the interstitial of a small Swiss river in the foothills of the Alps and its influence on gravel spawning brown trout (Salmo trutta L.)

NASA Astrophysics Data System (ADS)

Schindler, Yael; Michel, Christian; Holm, Patricia; Alewell, Christine

2010-05-01

The hyporheic zone can be characterized by multiple abiotic parameters (e.g. bulk density, texture, temperature, oxygen, ammonium, nitrate) which are all influenced directly or indirectly by the exchange processes between surface water and groundwater. These processes can vary both in time and space and are mainly driven by river discharge, ground water level and flow patterns. The input of fine sediment particles can change water-riverbed interactions through river bed clogging potentially affecting the embryonal development and survival of gravel spawning fish, such as brown trout (Salmo trutta L.). With our investigations we aim to understand these complex interactions spatially and temporally on a relevant small scale, i.e. within individual artificial brown trout redds. We designed an experimental field setup to directly investigate i) the influence of the abiotic river and redd environment on brown trout embryo development and ii) the hydrological dynamics affecting the abiotic environment in artificial brown trout. Additionally, our setup allows investigating the temporal dynamics of i) fine-sediment infiltration into the artificial redds and ii) embryo survival to two distinct developmental stages (i.e. eyed stage and hatch) The experiment was conducted in three sites of a typical Swiss river (Enziwigger, Canton of Luzern) with a strongly modified morphology. Individual sites represented a high, medium and low fine-sediment load. In each site, six artificial redds (18 in total) were built and data were collected during the entire incubation phase. Redds were located in places where natural spawning of brown trout is present. We adapted multiple established methods to the smaller scale of our river to study the dynamics of the most relevant abiotic parameters potentially affecting embryo development: Oxygen content and temperature was monitored continuously in different depths, fine sediment (bedload, suspended sediment load and its input in the river bed

The effects of biotic and abiotic factors on the spatial heterogeneity of alpine grassland vegetation at a small scale on the Qinghai-Tibet Plateau (QTP), China.

PubMed

Wen, Lu; Dong, Shi Kui; Li, Yuan Yuan; Sherman, Ruth; Shi, Jian Jun; Liu, De Mei; Wang, Yan Long; Ma, Yu Shou; Zhu, Lei

2013-10-01

Understanding the complex effects of biotic and abiotic factors on the composition of vegetation is very important for developing and implementing strategies for promoting sustainable grassland development. The vegetation-disturbance-environment relationship was examined in degraded alpine grasslands in the headwater areas of three rivers on the Qinghai-Tibet Plateau in this study. The investigated hypotheses were that (1) the heterogeneity of the vegetation of the alpine grassland is due to a combination of biotic and abiotic factors and that (2) at a small scale, biotic factors are more important for the distribution of alpine vegetation. On this basis, four transects were set along altitudinal gradients from 3,770 to 3,890 m on a sunny slope, and four parallel transects were set along altitudinal gradients on a shady slope in alpine grasslands in Guoluo Prefecture of Qinghai Province, China. It was found that biological disturbances were the major forces driving the spatial heterogeneity of the alpine grassland vegetation and abiotic factors were of secondary importance. Heavy grazing and intensive rat activity resulted in increases in unpalatable and poisonous weeds and decreased fine forages in the form of sedges, forbs, and grasses in the vegetation composition. Habitat degradation associated with biological disturbances significantly affected the spatial variation of the alpine grassland vegetation, i.e., more pioneer plants of poisonous or unpalatable weed species, such as Ligularia virgaurea and Euphorbia fischeriana, were found in bare patches. Environmental/abiotic factors were less important than biological disturbances in affecting the spatial distribution of the alpine grassland vegetation at a small scale. It was concluded that rat control and light grazing should be applied first in implementing restoration strategies. The primary vegetation in lightly grazed and less rat-damaged sites should be regarded as a reference for devising vegetation

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,…

De novo transcriptome sequence assembly and identification of AP2/ERF transcription factor related to abiotic stress in parsley (Petroselinum crispum).

PubMed

Li, Meng-Yao; Tan, Hua-Wei; Wang, Feng; Jiang, Qian; Xu, Zhi-Sheng; Tian, Chang; Xiong, Ai-Sheng

2014-01-01

Parsley is an important biennial Apiaceae species that is widely cultivated as herb, spice, and vegetable. Previous studies on parsley principally focused on its physiological and biochemical properties, including phenolic compound and volatile oil contents. However, little is known about the molecular and genetic properties of parsley. In this study, 23,686,707 high-quality reads were obtained and assembled into 81,852 transcripts and 50,161 unigenes for the first time. Functional annotation showed that 30,516 unigenes had sequence similarity to known genes. In addition, 3,244 putative simple sequence repeats were detected in curly parsley. Finally, 1,569 of the identified unigenes belonged to 58 transcription factor families. Various abiotic stresses have a strong detrimental effect on the yield and quality of parsley. AP2/ERF transcription factors have important functions in plant development, hormonal regulation, and abiotic response. A total of 88 putative AP2/ERF factors were identified from the transcriptome sequence of parsley. Seven AP2/ERF transcription factors were selected in this study to analyze the expression profiles of parsley under different abiotic stresses. Our data provide a potentially valuable resource that can be used for intensive parsley research.

De Novo Transcriptome Sequence Assembly and Identification of AP2/ERF Transcription Factor Related to Abiotic Stress in Parsley (Petroselinum crispum)

PubMed Central

Wang, Feng; Jiang, Qian; Xu, Zhi-Sheng; Tian, Chang; Xiong, Ai-Sheng

2014-01-01

Parsley is an important biennial Apiaceae species that is widely cultivated as herb, spice, and vegetable. Previous studies on parsley principally focused on its physiological and biochemical properties, including phenolic compound and volatile oil contents. However, little is known about the molecular and genetic properties of parsley. In this study, 23,686,707 high-quality reads were obtained and assembled into 81,852 transcripts and 50,161 unigenes for the first time. Functional annotation showed that 30,516 unigenes had sequence similarity to known genes. In addition, 3,244 putative simple sequence repeats were detected in curly parsley. Finally, 1,569 of the identified unigenes belonged to 58 transcription factor families. Various abiotic stresses have a strong detrimental effect on the yield and quality of parsley. AP2/ERF transcription factors have important functions in plant development, hormonal regulation, and abiotic response. A total of 88 putative AP2/ERF factors were identified from the transcriptome sequence of parsley. Seven AP2/ERF transcription factors were selected in this study to analyze the expression profiles of parsley under different abiotic stresses. Our data provide a potentially valuable resource that can be used for intensive parsley research. PMID:25268141

VpWRKY3, a biotic and abiotic stress-related transcription factor from the Chinese wild Vitis pseudoreticulata.

PubMed

Zhu, Ziguo; Shi, Jiangli; Cao, Jiangling; He, Mingyang; Wang, Yuejin

2012-11-01

Chinese wild grapevine Vitis pseudoreticulata accession 'Baihe-35-1' is identified as the precious resource with multiple resistances to pathogens. A directional cDNA library was constructed from the young leaves inoculated with Erysiphe necator. A total of 3,500 clones were sequenced, yielding 1,727 unigenes. Among them, 762 unigenes were annotated and classified into three classes, respectively, using Gene Ontology, including 22 ESTs related to transcription regulator activity. A novel WRKY transcription factor was isolated from the library, and designated as VpWRKY3 (GenBank Accession No. JF500755). The full-length cDNA is 1,280 bp, encoding a WRKY protein of 320 amino acids. VpWRKY3 is localized to nucleus and functions as a transcriptional activator. QRT-PCR analysis showed that the VpWRKY3 specifically accumulated in response to pathogen, salicylic acid, ethylene and drought stress. Overexpression of VpWRKY3 in tobacco increased the resistance to Ralstonia solanacearum, indicating that VpWRKY3 participates in defense response. Furthermore, VpWRKY3 is also involved in abscisic acid signal pathway and salt stress. This experiment provided an important basis for understanding the defense mechanisms mediated by WRKY genes in China wild grapevine. Generation of the EST collection from the cDNA library provided valuable information for the grapevine breeding. Key message We constructed a cDNA library from Chinese wild grapevine leaves inoculated with powdery mildew. VpWRKY3 was isolated and demonstrated that it was involved in biotic and abiotic stress responses.

Global analysis of WRKY transcription factor superfamily in Setaria identifies potential candidates involved in abiotic stress signaling

PubMed Central

Muthamilarasan, Mehanathan; Bonthala, Venkata S.; Khandelwal, Rohit; Jaishankar, Jananee; Shweta, Shweta; Nawaz, Kashif; Prasad, Manoj

2015-01-01

Transcription factors (TFs) are major players in stress signaling and constitute an integral part of signaling networks. Among the major TFs, WRKY proteins play pivotal roles in regulation of transcriptional reprogramming associated with stress responses. In view of this, genome- and transcriptome-wide identification of WRKY TF family was performed in the C4model plants, Setaria italica (SiWRKY) and S. viridis (SvWRKY), respectively. The study identified 105 SiWRKY and 44 SvWRKY proteins that were computationally analyzed for their physicochemical properties. Sequence alignment and phylogenetic analysis classified these proteins into three major groups, namely I, II, and III with majority of WRKY proteins belonging to group II (53 SiWRKY and 23 SvWRKY), followed by group III (39 SiWRKY and 11 SvWRKY) and group I (10 SiWRKY and 6 SvWRKY). Group II proteins were further classified into 5 subgroups (IIa to IIe) based on their phylogeny. Domain analysis showed the presence of WRKY motif and zinc finger-like structures in these proteins along with additional domains in a few proteins. All SiWRKY genes were physically mapped on the S. italica genome and their duplication analysis revealed that 10 and 8 gene pairs underwent tandem and segmental duplications, respectively. Comparative mapping of SiWRKY and SvWRKY genes in related C4 panicoid genomes demonstrated the orthologous relationships between these genomes. In silico expression analysis of SiWRKY and SvWRKY genes showed their differential expression patterns in different tissues and stress conditions. Expression profiling of candidate SiWRKY genes in response to stress (dehydration and salinity) and hormone treatments (abscisic acid, salicylic acid, and methyl jasmonate) suggested the putative involvement of SiWRKY066 and SiWRKY082 in stress and hormone signaling. These genes could be potential candidates for further characterization to delineate their functional roles in abiotic stress signaling. PMID:26635818

Global analysis of WRKY transcription factor superfamily in Setaria identifies potential candidates involved in abiotic stress signaling.

PubMed

Muthamilarasan, Mehanathan; Bonthala, Venkata S; Khandelwal, Rohit; Jaishankar, Jananee; Shweta, Shweta; Nawaz, Kashif; Prasad, Manoj

2015-01-01

Transcription factors (TFs) are major players in stress signaling and constitute an integral part of signaling networks. Among the major TFs, WRKY proteins play pivotal roles in regulation of transcriptional reprogramming associated with stress responses. In view of this, genome- and transcriptome-wide identification of WRKY TF family was performed in the C4model plants, Setaria italica (SiWRKY) and S. viridis (SvWRKY), respectively. The study identified 105 SiWRKY and 44 SvWRKY proteins that were computationally analyzed for their physicochemical properties. Sequence alignment and phylogenetic analysis classified these proteins into three major groups, namely I, II, and III with majority of WRKY proteins belonging to group II (53 SiWRKY and 23 SvWRKY), followed by group III (39 SiWRKY and 11 SvWRKY) and group I (10 SiWRKY and 6 SvWRKY). Group II proteins were further classified into 5 subgroups (IIa to IIe) based on their phylogeny. Domain analysis showed the presence of WRKY motif and zinc finger-like structures in these proteins along with additional domains in a few proteins. All SiWRKY genes were physically mapped on the S. italica genome and their duplication analysis revealed that 10 and 8 gene pairs underwent tandem and segmental duplications, respectively. Comparative mapping of SiWRKY and SvWRKY genes in related C4 panicoid genomes demonstrated the orthologous relationships between these genomes. In silico expression analysis of SiWRKY and SvWRKY genes showed their differential expression patterns in different tissues and stress conditions. Expression profiling of candidate SiWRKY genes in response to stress (dehydration and salinity) and hormone treatments (abscisic acid, salicylic acid, and methyl jasmonate) suggested the putative involvement of SiWRKY066 and SiWRKY082 in stress and hormone signaling. These genes could be potential candidates for further characterization to delineate their functional roles in abiotic stress signaling.

C2H2 type of zinc finger transcription factors in foxtail millet define response to abiotic stresses.

PubMed

Muthamilarasan, Mehanathan; Bonthala, Venkata Suresh; Mishra, Awdhesh Kumar; Khandelwal, Rohit; Khan, Yusuf; Roy, Riti; Prasad, Manoj

2014-09-01

C2H2 type of zinc finger transcription factors (TFs) play crucial roles in plant stress response and hormone signal transduction. Hence considering its importance, genome-wide investigation and characterization of C2H2 zinc finger proteins were performed in Arabidopsis, rice and poplar but no such study was conducted in foxtail millet which is a C4 Panicoid model crop well known for its abiotic stress tolerance. The present study identified 124 C2H2-type zinc finger TFs in foxtail millet (SiC2H2) and physically mapped them onto the genome. The gene duplication analysis revealed that SiC2H2s primarily expanded in the genome through tandem duplication. The phylogenetic tree classified these TFs into five groups (I-V). Further, miRNAs targeting SiC2H2 transcripts in foxtail millet were identified. Heat map demonstrated differential and tissue-specific expression patterns of these SiC2H2 genes. Comparative physical mapping between foxtail millet SiC2H2 genes and its orthologs of sorghum, maize and rice revealed the evolutionary relationships of C2H2 type of zinc finger TFs. The duplication and divergence data provided novel insight into the evolutionary aspects of these TFs in foxtail millet and related grass species. Expression profiling of candidate SiC2H2 genes in response to salinity, dehydration and cold stress showed differential expression pattern of these genes at different time points of stresses.

Abiotic regulation: a common way for proteins to modulate their functions.

PubMed

Zou, Zhi; Fu, Xinmiao

2015-01-01

Modulation of protein intrinsic activity in cells is generally carried out via a combination of four common ways, i.e., allosteric regulation, covalent modification, proteolytic cleavage and association of other regulatory proteins. Accumulated evidence indicate that changes of certain abiotic factors (e.g., temperature, pH, light and mechanical force) within or outside the cells directly influence protein structure and thus profoundly modulate the functions of a wide range of proteins, termed as abiotic regulatory proteins (e.g., heat shock factor, small heat shock protein, hemoglobin, zymogen, integrin, rhodopsin). Such abiotic regulation apparently differs from the four classic ways in perceiving and response to the signals. Importantly, it enables cells to directly and also immediately response to extracellular stimuli, thus facilitating the ability of organisms to resist against and adapt to the abiotic stress and thereby playing crucial roles in life evolution. Altogether, abiotic regulation may be considered as a common way for proteins to modulate their functions.

Epigenetic regulation of the expression of WRKY75 transcription factor in response to biotic and abiotic stresses in Solanaceae plants.

PubMed

López-Galiano, María José; González-Hernández, Ana I; Crespo-Salvador, Oscar; Rausell, Carolina; Real, M Dolores; Escamilla, Mónica; Camañes, Gemma; García-Agustín, Pilar; González-Bosch, Carmen; García-Robles, Inmaculada

2018-01-01

SlyWRKY75: gene expression was induced in response to biotic stresses, especially in Botrytis cinerea-infected tomato plants, in which Sly-miR1127-3p is a putative SlyWRKY75 regulator and epigenetic marks were detected. WRKY75 transcription factor involved in Pi homeostasis was recently found also induced in defense against necrotrophic pathogens. In this study, we analyzed by RT-qPCR the expression of SlyWRKY75 gene in tomato plants in response to abiotic stresses (drought or heat) and biotic stresses (Colorado potato beetle larvae infestation, Pseudomonas syringae or Botrytis cinerea infection) being only differentially expressed following biotic stresses, especially upon B. cinerea infection (55-fold induction). JA and JA-Ile levels were significantly increased in tomato plants under biotic stresses compared with control plants, indicating that SlyWRKY75 might be a transcriptional regulator of the JA pathway. The contribution of miRNAs and epigenetic molecular mechanisms to the regulation of this gene in B. cinerea-infected tomato plants was explored. We identified a putative Sly-miR1127-3p miRNA predicted to bind the intronic region of the SlyWRKY75 genomic sequence. Sly-miR1127-3p miRNA was repressed in infected plants (0.4-fold) supporting that it might act as an epigenetic regulation factor of SlyWRKY75 gene expression rather than via the post-transcriptional mechanisms of canonical miRNAs. It has been proposed that certain miRNAs can mediate DNA methylation in the plant nucleus broadening miRNA functions with transcriptional gene silencing by targeting intron-containing pre-mRNAs. Histone modifications analysis by chromatin immunoprecipitation (ChIP) demonstrated the presence of the activator histone modification H3K4me3 on SlyWRKY75 transcription start site and gene body. The induction of this gene in response to B. cinerea correlates with the presence of an activator mark. Thus, miRNAs and chromatin modifications might cooperate as epigenetic factors to

Direct and indirect effects of climate on demography and early growth of Pinus sylvestris at the rear edge: changing roles of biotic and abiotic factors.

PubMed

Benavides, Raquel; Rabasa, Sonia G; Granda, Elena; Escudero, Adrián; Hódar, José A; Martínez-Vilalta, Jordi; Rincón, Ana M; Zamora, Regino; Valladares, Fernando

2013-01-01

Global change triggers shifts in forest composition, with warming and aridification being particularly threatening for the populations located at the rear edge of the species distributions. This is the case of Scots pine (Pinus sylvestris) in the Mediterranean Basin where uncertainties in relation to its dynamics under these changing scenarios are still high. We analysed the relative effect of climate on the recruitment patterns of Scots pine and its interactions with local biotic and abiotic variables at different spatial scales. Number of seedlings and saplings was surveyed, and their annual shoot growth measured in 96 plots located across altitudinal gradients in three different regions in the Iberian Peninsula. We found a significant influence of climate on demography and performance of recruits, with a non-linear effect of temperature on the presence of juveniles, and a positive effect of precipitation on their survival. Abundance of juveniles of P. sylvestris that underwent their first summer drought was skewed towards higher altitudes than the altitudinal mean range of the conspecific adults and the optimum elevation for seedlings' emergence. At local level, light availability did not influence juveniles' density, but it enhanced their growth. Biotic interactions were found between juveniles and the herb cover (competition) and between the number of newly emerged seedlings and shrubs (facilitation). Results also highlighted the indirect effect that climate exerts over the local factors, modulating the interactions with the pre-existing vegetation that were more evident at more stressful sites. This multiscale approach improves our understanding of the dynamics of these marginal populations and some management criteria can be inferred to boost their conservation under the current global warming.

Factors influencing twins and zygosity.

PubMed

Hankins, Gary V D; Saade, George R

2005-01-01

Zygosity is influenced by many factors. Monozygotic twins occur spontaneously in approximately 1 in 250 births and are felt to increase twofold with ovulation induction techniques. Monozygotic twinning also increases in proportion to the number of blastocysts transferred during in vitro fertilisation. In contrast, dizygotic twinning appears to be influenced by race, genetic factors, maternal age, fertility enhancing drugs, folic acid supplementation, and maternal nutritional status.

Factors That Influence Language Growth.

ERIC Educational Resources Information Center

McCarthy, Dorothea, Ed.; And Others

This booklet contains four articles that discuss factors influencing language growth. The first, "The Child's Equipment for Language Growth" by Charlotte Wells, examines what the child needs for language learning, how the child uses his equipment for language growth, and what school factors facilitate the child's use of his equipment for language…

Kresoxim-methyl primes Medicago truncatula plants against abiotic stress factors via altered reactive oxygen and nitrogen species signalling leading to downstream transcriptional and metabolic readjustment

PubMed Central

Filippou, Panagiota; Antoniou, Chrystalla; Obata, Toshihiro; Van Der Kelen, Katrien; Harokopos, Vaggelis; Kanetis, Loukas; Aidinis, Vassilis; Van Breusegem, Frank; Fernie, Alisdair R; Fotopoulos, Vasileios

2016-01-01

Biotic and abiotic stresses, such as fungal infection and drought, cause major yield losses in modern agriculture. Kresoxim-methyl (KM) belongs to the strobilurins, one of the most important classes of agricultural fungicides displaying a direct effect on several plant physiological and developmental processes. However, the impact of KM treatment on salt and drought stress tolerance is unknown. In this study we demonstrate that KM pre-treatment of Medicago truncatula plants results in increased protection to drought and salt stress. Foliar application with KM prior to stress imposition resulted in improvement of physiological parameters compared with stressed-only plants. This protective effect was further supported by increased proline biosynthesis, modified reactive oxygen and nitrogen species signalling, and attenuation of cellular damage. In addition, comprehensive transcriptome analysis identified a number of transcripts that are differentially accumulating in drought- and salinity-stressed plants (646 and 57, respectively) after KM pre-treatment compared with stressed plants with no KM pre-treatment. Metabolomic analysis suggests that the priming role of KM in drought- and to a lesser extent in salinity-stressed plants can be attributed to the regulation of key metabolites (including sugars and amino acids) resulting in protection against abiotic stress factors. Overall, the present study highlights the potential use of this commonly used fungicide as a priming agent against key abiotic stress conditions. PMID:26712823

Transcriptional profiling of Medicago truncatula under salt stress identified a novel CBF transcription factor MtCBF4 that plays an important role in abiotic stress responses

PubMed Central

2011-01-01

Background Salt stress hinders the growth of plants and reduces crop production worldwide. However, different plant species might possess different adaptive mechanisms to mitigate salt stress. We conducted a detailed pathway analysis of transcriptional dynamics in the roots of Medicago truncatula seedlings under salt stress and selected a transcription factor gene, MtCBF4, for experimental validation. Results A microarray experiment was conducted using root samples collected 6, 24, and 48 h after application of 180 mM NaCl. Analysis of 11 statistically significant expression profiles revealed different behaviors between primary and secondary metabolism pathways in response to external stress. Secondary metabolism that helps to maintain osmotic balance was induced. One of the highly induced transcription factor genes was successfully cloned, and was named MtCBF4. Phylogenetic analysis revealed that MtCBF4, which belongs to the AP2-EREBP transcription factor family, is a novel member of the CBF transcription factor in M. truncatula. MtCBF4 is shown to be a nuclear-localized protein. Expression of MtCBF4 in M. truncatula was induced by most of the abiotic stresses, including salt, drought, cold, and abscisic acid, suggesting crosstalk between these abiotic stresses. Transgenic Arabidopsis over-expressing MtCBF4 enhanced tolerance to drought and salt stress, and activated expression of downstream genes that contain DRE elements. Over-expression of MtCBF4 in M. truncatula also enhanced salt tolerance and induced expression level of corresponding downstream genes. Conclusion Comprehensive transcriptomic analysis revealed complex mechanisms exist in plants in response to salt stress. The novel transcription factor gene MtCBF4 identified here played an important role in response to abiotic stresses, indicating that it might be a good candidate gene for genetic improvement to produce stress-tolerant plants. PMID:21718548

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…

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…

Genome-wide characterization and expression analysis enables identification of abiotic stress-responsive MYB transcription factors in cassava (Manihot esculenta).

PubMed

Ruan, Meng-Bin; Guo, Xin; Wang, Bin; Yang, Yi-Ling; Li, Wen-Qi; Yu, Xiao-Ling; Zhang, Peng; Peng, Ming

2017-06-15

The myeloblastosis (MYB) transcription factor superfamily is the largest transcription factor family in plants, playing different roles during stress response. However, abiotic stress-responsive MYB transcription factors have not been systematically studied in cassava (Manihot esculenta), an important tropical tuber root crop. In this study, we used a genome-wide transcriptome analysis to predict 299 putative MeMYB genes in the cassava genome. Under drought and cold stresses, many MeMYB genes exhibited different expression patterns in cassava leaves, indicating that these genes might play a role in abiotic stress responses. We found that several stress-responsive MeMYB genes responded to abscisic acid (ABA) in cassava leaves. We characterize four MeMYBs, namely MeMYB1, MeMYB2, MeMYB4, and MeMYB9, as R2R3-MYB transcription factors. Furthermore, RNAi-driven repression of MeMYB2 resulted in drought and cold tolerance in transgenic cassava. Gene expression assays in wild-type and MeMYB2-RNAi cassava plants revealed that MeMYB2 may affect other MeMYBs as well as MeWRKYs under drought and cold stress, suggesting crosstalk between MYB and WRKY family genes under stress conditions in cassava. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Effects of soil abiotic factors on the plant morphology in an intertidal salt marsh, Yellow River Delta, China

NASA Astrophysics Data System (ADS)

Li, Shanze; Cui, Baoshan; Bai, Junhong; Xie, Tian; Yan, Jiaguo; Wang, Qing; Zhang, Shuyan

2018-02-01

Plant morphology plays important role in studying biogeography in many ecosystems. Suadea salsa, as a native plant community of northern China and an important habitat for diversity of waterbirds and macrobenthos, has often been overlooked. Nowadays, S. salsa community is facing great loss due to coastal reclamation activities and natural disturbances. To maintain and restore S. salsa community, it's important to address the plant morphology across marsh zones, as well as its relationships with local soil abiotic conditions. In our studied intertidal salt marsh, we found that less flood disturbance frequency, softer soil conditions, rich soil organic matter, total carbon and total nitrogen, lower water depth and water content, less species competition will benefit S. salsa plant in the morphology of high coverage, above-ground biomass, shoot height and leaf length. Lower soil porewater salinity will benefit the below-ground biomass of S. salsa. Thus, we recommend managers help alleviate soil abiotic stresses in the intertidal salt marshes, making the soil conditions more suitable for S. salsa growth and succession.

Genome-wide identification of WRKY transcription factors in kiwifruit (Actinidia spp.) and analysis of WRKY expression in responses to biotic and abiotic stresses.

PubMed

Jing, Zhaobin; Liu, Zhande

2018-04-01

As one of the largest transcriptional factor families in plants, WRKY transcription factors play important roles in various biotic and abiotic stress responses. To date, WRKY genes in kiwifruit (Actinidia spp.) remain poorly understood. In our study, o total of 97 AcWRKY genes have been identified in the kiwifruit genome. An overview of these AcWRKY genes is analyzed, including the phylogenetic relationships, exon-intron structures, synteny and expression profiles. The 97 AcWRKY genes were divided into three groups based on the conserved WRKY domain. Synteny analysis indicated that segmental duplication events contributed to the expansion of the kiwifruit AcWRKY family. In addition, the synteny analysis between kiwifruit and Arabidopsis suggested that some of the AcWRKY genes were derived from common ancestors before the divergence of these two species. Conserved motifs outside the AcWRKY domain may reflect their functional conservation. Genome-wide segmental and tandem duplication were found, which may contribute to the expansion of AcWRKY genes. Furthermore, the analysis of selected AcWRKY genes showed a variety of expression patterns in five different organs as well as during biotic and abiotic stresses. The genome-wide identification and characterization of kiwifruit WRKY transcription factors provides insight into the evolutionary history and is a useful resource for further functional analyses of kiwifruit.

Functional and DNA-protein binding studies of WRKY transcription factors and their expression analysis in response to biotic and abiotic stress in wheat (Triticum aestivum L.).

PubMed

Satapathy, Lopamudra; Kumar, Dhananjay; Kumar, Manish; Mukhopadhyay, Kunal

2018-01-01

WRKY, a plant-specific transcription factor family, plays vital roles in pathogen defense, abiotic stress, and phytohormone signalling. Little is known about the roles and function of WRKY transcription factors in response to rust diseases in wheat. In the present study, three TaWRKY genes encoding complete protein sequences were cloned. They belonged to class II and III WRKY based on the number of WRKY domains and the pattern of zinc finger structures. Twenty-two DNA-protein binding docking complexes predicted stable interactions of WRKY domain with W-box. Quantitative real-time-PCR using wheat near-isogenic lines with or without Lr28 gene revealed differential up- or down-regulation in response to biotic and abiotic stress treatments which could be responsible for their functional divergence in wheat. TaWRKY62 was found to be induced upon treatment with JA, MJ, and SA and reduced after ABA treatments. Maximum induction of six out of seven genes occurred at 48 h post inoculation due to pathogen inoculation. Hence, TaWRKY (49, 50 , 52 , 55 , 57, and 62 ) can be considered as potential candidate genes for further functional validation as well as for crop improvement programs for stress resistance. The results of the present study will enhance knowledge towards understanding the molecular basis of mode of action of WRKY transcription factor genes in wheat and their role during leaf rust pathogenesis in particular.

Plant community, geographic distance and abiotic factors play different roles in predicting AMF biogeography at the regional scale in northern China.

PubMed

Xu, Tianle; Veresoglou, Stavros D; Chen, Yongliang; Rillig, Matthias C; Xiang, Dan; Ondřej, Daniel; Hao, Zhipeng; Liu, Lei; Deng, Ye; Hu, Yajun; Chen, Weiping; Wang, Juntao; He, Jizheng; Chen, Baodong

2016-12-01

Arbuscular mycorrhizal fungi (AMF) are ubiquitous mutualists of terrestrial plants and play key roles in regulating various ecosystem processes, but little is known about AMF biogeography at regional scale. This study aims at exploring the key predictors of AMF communities across a 5000-km transect in northern China. We determined the soil AMF species richness and community composition at 47 sites representative of four vegetation types (meadow steppe, typical steppe, desert steppe and desert) and related them to plant community characteristics, abiotic factors and geographic distance. The results showed that soil pH was the strongest predictor of AMF richness and phylogenetic diversity. However, abiotic factors only have a low predictive effect on AMF community composition or phylogenetic patterns. By contrast, we found a significant relationship between community composition of AMF and plants, which was a surprising result given the extent of heterogeneity in the plant community across this transect. Moreover, the geographic distance predominantly explained the AMF phylogenetic structure, implying that history evolutionary may play a role in shaping AMF biogeographic patterns. This study highlighted the different roles of main factors in predicting AMF biogeography, and bridge landscape-scale studies to more recent global-scale efforts. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

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

Factors influencing children's food choice.

PubMed

Koivisto Hursti, U K

1999-04-01

Although food habits are not stable and unchanging during a person's lifetime, a base for healthy food habits can be created in early childhood. Children's food habits can be assumed to be influenced by their parents' food habits and choices. The aim of this article is to review factors influencing food choice in children as well as in adults. The results demonstrate that the development of children's food habits is influenced by a multitude of factors. Parents play an important role in the formation of food habits and preferences of young children. They can influence their children's food choice by making specific foods available, by acting as models for their children and by their behaviour in specific situations. Children tend to be afraid of new foods and do not readily accept them. However, experience is known to enhance preference, and earlier experiences of a particular food are the major determinants of the development of children's food acceptance patterns. Thus, parents should be encouraged to make healthy foods easily available to the child and serve these foods in positive mealtime situations in order to help their child to develop healthy food habits.

Factors influencing children's food choice.

PubMed

Hursti, Ulla-Kaisa Koivisto

1999-01-01

Although food habits arc not stable and unchanging during a person's lifetime, a base for healthy food habits can be created in early childhood. Children's food habits can be assumed to be influenced by their parents' food habits and choices. The aim of this article is to review factors influencing food choice in children as well as in adults. The results demonstrate that the development of children's food habits is influenced by a multitude of factors. Parents play an important role in the formation of food habits and preferences of young children. They can influence their children's food choice by making specific foods available, by acting as models for their children and by their behaviour in specific situations. Children tend to be afraid of new foods and do not readily accept them. However, experience is known to enhance preference, and earlier experiences of a particular food are the major determinants of the development of children's food acceptance patterns. Thus, parents should be encouraged to make healthy foods easily available to the child and serve these foods in positive mealtime situations in order to help their child to develop healthy food habits.

Stress inducible expression of the DREB1A transcription factor from xeric, Hordeum spontaneum L. in turf and forage grass (Paspalum notatum Flugge) enhances abiotic stress tolerance.

PubMed

James, Victoria A; Neibaur, Isaac; Altpeter, Fredy

2008-02-01

The dehydration-responsive element binding proteins (DREB1)/C-repeat (CRT) binding factors (CBF) function as transcription activators and bind to the DRE/CRT cis-acting element commonly present in the promoters of abiotic stress-regulated genes. A DREB1A transcription factor ortholog was isolated from a xeric, wild barley (Hordeum spontaneum L.) accession, originating from the Negev desert. Sequence comparison revealed a very high degree of sequence conservation of HsDREB1A to the published barley (Hordeum vulgare L.) DREB1A. Constitutive expression of the HsDREB1A gene was able to trans-activate a reporter gene under transcriptional control of the stress-inducible HVA1s and Dhn8 promoters. HsDREB1A was subcloned under transcriptional control of the stress-inducible barley HVA1s promoter and introduced into the apomictic bahiagrass (Paspalum notatum Flugge) cultivar 'Argentine'. HsDREB1A integration and stress inducible expression was detected in primary transgenic bahiagrass plants and apomictic seed progeny by Southern blot, RT-PCR and northern blot analysis respectively. Transgenic bahiagrass plants with stress-inducible expression of HsDREB1A survived severe salt stress and repeated cycles of severe dehydration stress under controlled environment conditions, in contrast to non-transgenic plants. The observed abiotic stress tolerance is very desirable in turf and forage grasses like bahiagrass, where seasonal droughts and irrigation restrictions affect establishment, persistence or productivity of this perennial crop.

Factors influencing perceived angular velocity.

PubMed

Kaiser, M K; Calderone, J B

1991-11-01

The assumption that humans are able to perceive and process angular kinematics is critical to many structure-from-motion and optical flow models. The current studies investigate this sensitivity, and examine several factors likely to influence angular velocity perception. In particular, three factors are considered: (1) the extent to which perceived angular velocity is determined by edge transitions of surface elements, (2) the extent to which angular velocity estimates are influenced by instantaneous linear velocities of surface elements, and (3) whether element-velocity effects are related to three-dimensional (3-D) tangential velocities or to two-dimensional (2-D) image velocities. Edge-transition rate biased angular velocity estimates only when edges were highly salient. Element velocities influenced perceived angular velocity; this bias was related to 2-D image velocity rather than 3-D tangential velocity. Despite these biases, however, judgments were most strongly determined by the true angular velocity. Sensitivity to this higher order motion parameter was surprisingly good, for rotations both in depth (y-axis) and parallel to the line of sight (z-axis).

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

Genome Wide Analysis of the Apple MYB Transcription Factor Family Allows the Identification of MdoMYB121 Gene Confering Abiotic Stress Tolerance in Plants

PubMed Central

Wang, Rong-Kai; Zhang, Rui-Fen; Hao, Yu-Jin

2013-01-01

The MYB proteins comprise one of the largest families of transcription factors (TFs) in plants. Although several MYB genes have been characterized to play roles in secondary metabolism, the MYB family has not yet been identified in apple. In this study, 229 apple MYB genes were identified through a genome-wide analysis and divided into 45 subgroups. A computational analysis was conducted using the apple genomic database to yield a complete overview of the MYB family, including the intron-exon organizations, the sequence features of the MYB DNA-binding domains, the carboxy-terminal motifs, and the chromosomal locations. Subsequently, the expression of 18 MYB genes, including 12 were chosen from stress-related subgroups, while another 6 ones from other subgroups, in response to various abiotic stresses was examined. It was found that several of these MYB genes, particularly MdoMYB121, were induced by multiple stresses. The MdoMYB121 was then further functionally characterized. Its predicted protein was found to be localized in the nucleus. A transgenic analysis indicated that the overexpression of the MdoMYB121 gene remarkably enhanced the tolerance to high salinity, drought, and cold stresses in transgenic tomato and apple plants. Our results indicate that the MYB genes are highly conserved in plant species and that MdoMYB121 can be used as a target gene in genetic engineering approaches to improve the tolerance of plants to multiple abiotic stresses. PMID:23950843

Seasonal variation in abiotic factors and ferulic acid toxicity in snail-attractant pellets against the intermediate host snail Lymnaea acuminata.

PubMed

Agrahari, P; Singh, D K

2013-11-01

Laboratory evaluation was made to access the seasonal variations in abiotic environmental factors temperature, pH, dissolved oxygen, carbon dioxide, electrical conductivity and ferulic acid toxicity in snail-attractant pellets (SAP) against the intermediate host snail Lymnaea acuminata in each month of the years 2010 and 2011. On the basis of a 24-h toxicity assay, it was noted that lethal concentration values of 4.03, 3.73% and 4.45% in SAP containing starch and 4.16, 4.23% and 4.29% in SAP containing proline during the months of May, June and September, respectively, were most effective in killing the snails, while SAP containing starch/proline + ferulic acid was least effective in the month of January/February (24-h lethal concentration value was 7.67%/7.63% in SAP). There was a significant positive correlation between lethal concentration value of ferulic acid containing SAP and levels of dissolved O2 /pH of water in corresponding months. On the contrary, a negative correlation was observed between lethal concentration value and dissolved CO2 /temperature of test water in the same months. To ascertain that such a relationship between toxicity and abiotic factors is not co-incidental, the nervous tissue of treated (40% and 80% of 24-h lethal concentration value) and control group of snails was assayed for the activity of acetylcholinesterase (AChE) in each of the 12 months of the same year. There was a maximum inhibition of 58.43% of AChE, in snails exposed to 80% of the 24-h lethal concentration value of ferulic acid + starch in the month of May. This work shows conclusively that the best time to control snail population with SAP containing ferulic acid is during the months of May, June and September. © 2012 Blackwell Verlag GmbH.

The auxin response factor gene family in banana: genome-wide identification and expression analyses during development, ripening, and abiotic stress

PubMed Central

Hu, Wei; Zuo, Jiao; Hou, Xiaowan; Yan, Yan; Wei, Yunxie; Liu, Juhua; Li, Meiying; Xu, Biyu; Jin, Zhiqiang

2015-01-01

Auxin signaling regulates various auxin-responsive genes via two types of transcriptional regulators, Auxin Response Factors (ARF) and Aux/IAA. ARF transcription factors act as critical components of auxin signaling that play important roles in modulating various biological processes. However, limited information about this gene family in fruit crops is currently available. Herein, 47 ARF genes were identified in banana based on its genome sequence. Phylogenetic analysis of the ARFs from banana, rice, and Arabidopsis suggested that the ARFs could be divided into four subgroups, among which most ARFs from the banana showed a closer relationship with those from rice than those from Arabidopsis. Conserved motif analysis showed that all identified MaARFs had typical DNA-binding and ARF domains, but 12 members lacked the dimerization domain. Gene structure analysis showed that the number of exons in MaARF genes ranged from 5 to 21, suggesting large variation amongst banana ARF genes. The comprehensive expression profiles of MaARF genes yielded useful information about their involvement in diverse tissues, different stages of fruit development and ripening, and responses to abiotic stresses in different varieties. Interaction networks and co-expression assays indicated the strong transcriptional response of banana ARFs and ARF-mediated networks in early fruit development for different varieties. Our systematic analysis of MaARFs revealed robust tissue-specific, development-dependent, and abiotic stress-responsive candidate MaARF genes for further functional assays in planta. These findings could lead to potential applications in the genetic improvement of banana cultivars, and yield new insights into the complexity of the control of MaARF gene expression at the transcriptional level. Finally, they support the hypothesis that ARFs are a crucial component of the auxin signaling pathway, which regulates a wide range of physiological processes. PMID:26442055

Effects of biotic and abiotic factors on the distribution and abundance of larval two-lined salamanders (Eurycea bislineata) across spatial scales.

PubMed

Barr, Garrett E; Babbitt, Kimberly J

2002-10-01

We sampled eight streams in the White Mountain National Forest, New Hampshire, throughout their elevational reach for larval salamanders and predatory fish to examine the effects of abiotic factors and predation on the distribution and abundance of larval salamanders. Eurycea bislineata (two-lined salamander) and Salvelinus fontinalis (brook trout) abundance varied among and within streams. Eurycea bislineata showed a negative association with S. fontinalis across spatial scales (micro-scale, among quadrats; meso-scale, among pool/riffle pairs; macro-scale, among streams). At the smallest scale, the average density of larval E. bislineata was greatest in microhabitats with relatively high boulder cover and low sand and bare rock cover only in the presence of S. fontinalis; no such relationship was observed in the absence of S. fontinalis. In a mesocosm experiment, larval salamander survival was higher in enclosures containing cobbles than enclosures containing a gravel mix, illustrating the advantage of coarse substrates with interstitial spaces that are inaccessible to predatory fish. At the meso-scale, E. bislineata larvae were less abundant in stream sections with S. fontinalis than those without. Among streams, those with many S. fontinalis had fewer E. bislineata. Of the abiotic parameters measured, water temperature and pH were positively related to E. bislineata presence, and elevation, water temperature, pH, canopy cover, and gradient were positively related to E. bislineata abundance. Larval Plethodontid salamanders can reach high densities and appear to have strong interactions with stream biota, thus their functional role in stream communities deserves further attention.

[Endocrine factors influencing melanoma progression].

PubMed

Dobos, Judit

2009-03-01

According to recent findings that beside cancers traditionally considered as hormone-dependent, several other tumor types show different behavior in the two sexes, indicating the possible role of endocrine factors in the course of these diseases. The possibility that endocrine factors may influence the clinical course of human malignant melanoma is suggested by the higher survival rate in premenopausal vs. postmenopausal women or men of any ages. However, investigations on the sex hormone receptor status of human cutaneous melanomas and experiments attempting to support the epidemiological results yielded conflicting results. In our human melanoma cell lines we failed to detect steroid receptors at protein level, while quantitative PCR demonstrated that their mRNA expression level was orders of magnitude lower compared to the positive control cell lines. Sex hormones did not influence the in vitro features of the human melanoma cells considerably. On the other hand, glucocorticoid receptor was present both at mRNA and protein level, although dexamethasone was effective in vitro only at high doses. Our previous experiments showed that intrasplenic injection of human melanoma cells resulted in a significantly higher number of liver colonies in male than in female SCID mice. We now show that this difference evolves during the first day. After injection into the tail vein we did not observe gender-dependent difference in the efficiency of pulmonary colonization. Examining the pattern of metastasis formation after intracardiac injection, we have found differences between the two sexes in the incidence or number of colonies only in the case of the liver but not in other organs. We concluded that the observed phenomenon is specific to the liver; therefore we investigated the effects of 2-methoxyestradiol, an endogenous metabolite of estradiol produced mainly in the liver, with an estrogen receptor-independent antitumor activity. 2ME2 effectively inhibited melanoma cell

Use of a Generalized Additive Model to Investigate Key Abiotic Factors Affecting Microcystin Cellular Quotas in Heavy Bloom Areas of Lake Taihu

PubMed Central

Tao, Min; Xie, Ping; Chen, Jun; Qin, Boqiang; Zhang, Dawen; Niu, Yuan; Zhang, Meng; Wang, Qing; Wu, Laiyan

2012-01-01

Lake Taihu is the third largest freshwater lake in China and is suffering from serious cyanobacterial blooms with the associated drinking water contamination by microcystin (MC) for millions of citizens. So far, most studies on MCs have been limited to two small bays, while systematic research on the whole lake is lacking. To explain the variations in MC concentrations during cyanobacterial bloom, a large-scale survey at 30 sites across the lake was conducted monthly in 2008. The health risks of MC exposure were high, especially in the northern area. Both Microcystis abundance and MC cellular quotas presented positive correlations with MC concentration in the bloom seasons, suggesting that the toxic risks during Microcystis proliferations were affected by variations in both Microcystis density and MC production per Microcystis cell. Use of a powerful predictive modeling tool named generalized additive model (GAM) helped visualize significant effects of abiotic factors related to carbon fixation and proliferation of Microcystis (conductivity, dissolved inorganic carbon (DIC), water temperature and pH) on MC cellular quotas from recruitment period of Microcystis to the bloom seasons, suggesting the possible use of these factors, in addition to Microcystis abundance, as warning signs to predict toxic events in the future. The interesting relationship between macrophytes and MC cellular quotas of Microcystis (i.e., high MC cellular quotas in the presence of macrophytes) needs further investigation. PMID:22384128

Biotic and abiotic factors affecting the genetic structure and diversity of butternut in the southern Appalachian Mountains, USA

Treesearch

Amanda Parks; Michael Jenkins; Michael Ostry; Peng Zhao; Keith Woeste

2014-01-01

The abundance of butternut (Juglans cinerea L.) trees has severely declined rangewide over the past 50 years. An important factor in the decline is butternut canker, a disease caused by the fungus Ophiognomonia clavigigentijuglandacearum, which has left the remaining butternuts isolated and sparsely distributed. To manage the...

Temporal Dynamics of Abiotic and Biotic Factors on Leaf Litter of Three Plant Species in Relation to Decomposition Rate along a Subalpine Elevation Gradient

PubMed Central

Zhu, Jianxiao; Yang, Wanqin; He, Xinhua

2013-01-01

Relationships between abiotic (soil temperature and number of freeze-thaw cycles) or biotic factors (chemical elements, microbial biomass, extracellular enzymes, and decomposer communities in litter) and litter decomposition rates were investigated over two years in subalpine forests close to the Qinghai-Tibet Plateau in China. Litterbags with senescent birch, fir, and spruce leaves were placed on the forest floor at 2,704 m, 3,023 m, 3,298 m, and 3,582 m elevation. Results showed that the decomposition rate positively correlated with soil mean temperature during the plant growing season, and with the number of soil freeze-thaw cycles during the winter. Concentrations of soluble nitrogen (N), phosphorus (P) and potassium (K) had positive effects but C:N and lignin:N ratios had negative effects on the decomposition rate (k), especially during the winter. Meanwhile, microbial biomass carbon (MBC), N (MBN), and P (MBP) were positively correlated with k values during the first growing season. These biotic factors accounted for 60.0% and 56.4% of the variation in decomposition rate during the winter and the growing season in the first year, respectively. Specifically, litter chemistry (C, N, P, K, lignin, C:N and lignin:N ratio) independently explained 29.6% and 13.3%, and the microbe-related factors (MBC, MBN, MBP, bacterial and fungal biomass, sucrase and ACP activity) explained 22.9% and 34.9% during the first winter and the first growing season, respectively. We conclude that frequent freeze-thaw cycles and litter chemical properties determine the winter decomposition while microbe-related factors play more important roles in determining decomposition in the subsequent growing season. PMID:23620803

Abiotic controls on N2O emissions from soils and wetlands

NASA Astrophysics Data System (ADS)

Horwath, W. R.

2016-12-01

The increase in atmospheric nitrous oxide (N2O) is a critical climate change issue contributing to global warming. Most studies on N2O production attribute microbial processes and their associated enzymatic reactions to be the main driver affecting emissions. The role of redox capable iron, manganese and organic compounds that can react with intermediates in the nitrogen cycle has also been shown to produce N2O abiotically. The importance of the abiotic pathways, however, is highly debated. The abiotic production of N2O is related to biophysiochemical controls and unique isotopic signatures of nitrogen cycle intermediates (hydroxylamine, nitric oxide, and nitrite), redox-active metals (iron and manganese) and organic matter (humic and fulvic acids). In a range of soils, we find that the iron directly associated with organic compounds is the strongest variable relating to N2O emissions. In addition to these factors, management is also assumed to affect abiotic N2O production through its impact on nitrogen cycle intermediates, but the environmental and physiochemical conditions that are changed by management are rarely considered in the abiotic production of N2O. We find that the amount and quality of organic compounds in soils directly determines the fate of soil N2O production (i.e. be emitted or consumed). Water depth in rice paddies and wetlands also plays a significant role in partitioning production and consumption of N2O. What is evident from studies on N2O emission is that abiotic reactions are coupled to biotic processes and they cannot be easily separated. The biotic/abiotic interactions have important ecological outcomes that influence abiotic production mechanisms and should be recognized as important controllers of N2O production and consumption processes in soils and sediments.

Biotic and abiotic factors related to rainbow smelt recruitment in the Wisconsin waters of Lake Superior, 1978-1997

USGS Publications Warehouse

Hoff, Michael H.

2004-01-01

Lake Superior rainbow smelt (Osmerus mordax) recruitment to 12-13 months of age in the Wisconsin waters of Lake Superior varied by a factor of 9.3 during 1978-1997. Management agencies have sought models that accurately predict recruitment, but no satisfactory models had previously been developed. In this study, modeling was conducted to determine which factors best explained recruitment variability. The Ricker stock-recruitment model derived from only the paired stock and recruit data accounted for 63% of the variability in recruitment data. The functional relationship that accounted for the greatest amount of recruitment variation (81%) included rainbow smelt stock size, May rainfall, and bloater (Coregonus hoyi) biomass. Model results were interpreted to mean that recruitment was affected negatively by increased river flows from increased rainfall, and affected positively by the biomass of bloater, and those results were interpreted to mean that bloater mediated the effects of lake trout predation on rainbow smelt recruits. Model results were also interpreted to mean that stock size caused compensatory, density-dependent mortality on rainbow smelt recruits. Correlations observed here may be of value to managers seeking approaches to either enhance or control populations of this species, which is not indigenous to the Great Lakes.

The membrane tethered transcription factor EcbZIP17 from finger millet promotes plant growth and enhances tolerance to abiotic stresses.

PubMed

Ramakrishna, Chopperla; Singh, Sonam; Raghavendrarao, Sangala; Padaria, Jasdeep C; Mohanty, Sasmita; Sharma, Tilak Raj; Solanke, Amolkumar U

2018-02-01

The occurrence of various stresses, as the outcome of global climate change, results in the yield losses of crop plants. Prospecting of genes in stress tolerant plant species may help to protect and improve their agronomic performance. Finger millet (Eleusine coracana L.) is a valuable source of superior genes and alleles for stress tolerance. In this study, we isolated a novel endoplasmic reticulum (ER) membrane tethered bZIP transcription factor from finger millet, EcbZIP17. Transgenic tobacco plants overexpressing this gene showed better vegetative growth and seed yield compared with wild type (WT) plants under optimal growth conditions and confirmed upregulation of brassinosteroid signalling genes. Under various abiotic stresses, such as 250 mM NaCl, 10% PEG6000, 400 mM mannitol, water withdrawal, and heat stress, the transgenic plants showed higher germination rate, biomass, primary and secondary root formation, and recovery rate, compared with WT plants. The transgenic plants exposed to an ER stress inducer resulted in greater leaf diameter and plant height as well as higher expression of the ER stress-responsive genes BiP, PDIL, and CRT1. Overall, our results indicated that EcbZIP17 improves plant growth at optimal conditions through brassinosteroid signalling and provide tolerance to various environmental stresses via ER signalling pathways.

Aquatic macroinvertebrates associated with Eichhornia azurea (Swartz) Kunth and relationships with abiotic factors in marginal lentic ecosystems (São Paulo, Brazil).

PubMed

Silva, C V; Henry, R

2013-02-01

Marginal lakes are characterised by their having high biological diversity due to the presence of aquatic macrophytes in their coastal zones, providing habitats for refuge and food for animal community members. Among the fauna components associated with macrophytes, aquatic macroinvertebrates are important because they are an energy source for predators and fish. In six lakes and two different seasons (March and August 2009), the ecological attributes of aquatic macroinvertebrate community associated with Eichhornia azurea were compared and the controlling environmental factors were identified. Since the attributes of macroinvertebrate community are strictly associated with abiotic variables of each distinct habitat, our hypothesis was that each site associated with the same floating aquatic macrophyte (E. azurea) should have a typical composition and density of organisms. We identified 50 taxa of macroinvertebrates, with greater taxa richness for aquatic insects (37 taxa) divided into eight orders; the order Diptera being the most abundant in the two study periods. On the other hand, higher values of total taxa richness were recorded in August. Dissolved oxygen and pH presented the greatest number of significant positive correlations with the different taxa. The animals most frequently collected in the six lakes in March and August 2009 were Hirudinea, Oligochaeta, Hydrachnidae, Conchostraca, Ostracoda, Noteridae, Ceratopogonidae, Chironomidae, Culicidae, Caenidae, Pleidae, Aeshnidae, Libellulidae, Coenagrionidae and Nematoda. Only densities of Trichoptera, Ostracoda and Conchostraca presented the highest significant differences between lakes in both study periods and considering the composition of macroinvertebrates no significant differences were registered for macroinvertebrate composition.

Biotic and abiotic factors related to lake herring recruitment in the Wisconsin waters of Lake Superior, 1984-1998

USGS Publications Warehouse

Hoff, Michael H.

2004-01-01

Lake Superior lake herring (Coregonus artedi) recruitment to 13-14 months of age in the Wisconsin waters of Lake Superior varied by a factor of 5,233 during 1984-1998. Management agencies have sought models that accurately predict recruitment, but no satisfactory model had previously been developed. Lake herring recruitment was modeled to determine which factors most explained recruitment variability. The Ricker stock-recruitment model derived from only the paired stock and recruit data explained 35% of the variability in the recruitment data. The functional relationship that explained the greatest amount of recruitment variation (93%) included lake herring stock size, lake trout (Salvelinus namaycush) population size, slimy sculpin (Cottus cognatus) biomass, the interaction of mean daily wind speed in April (month of hatch) and lake herring stock size, and mean air temperature in April (when lake herring are 12-months old). Model results were interpreted to mean that lake herring recruitment was affected negatively by: slimy sculpin predation on lake herring ova; predation on age-0 lake herring by lake trout; and adult cannibalism on lake herring larvae, which was reduced by increased wind speed. April temperature was the variable that explained the least amount of variability in recruitment, but lake herring recruitment was positively affected by a warm April, which shortened winter and apparently reduced first-winter mortality. Stock size caused compensatory, density-dependent mortality on lake herring recruits. Management efforts appear best targeted at stock size protection, and empirical data implies that stock size in the Wisconsin waters of the lake should be maintained at 2.1-15.0 adults/ha in spring, bottom-trawl surveys.

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…

Molecular cloning and expression profile of an abiotic stress and hormone responsive MYB transcription factor gene from Panax ginseng.

PubMed

Afrin, Sadia; Zhu, Jie; Cao, Hongzhe; Huang, Jingjia; Xiu, Hao; Luo, Tiao; Luo, Zhiyong

2015-04-01

The v-myb avian myeloblastosis viral oncogene homolog (MYB) family constitutes one of the most abundant groups of transcription factors and plays vital roles in developmental processes and defense responses in plants. A ginseng (Panax ginseng C.A. Meyer) MYB gene was cloned and designated as PgMYB1. The cDNA of PgMYB1 is 762 base pairs long and encodes the R2R3-type protein consisting 238 amino acids. Subcellular localization showed that PgMYB1-mGFP5 fusion protein was specifically localized in the nucleus. To understand the functional roles of PgMYB1, we investigated the expression patterns of PgMYB1 in different tissues and under various conditions. Quantitative real-time polymerase chain reaction and western blot analysis showed that PgMYB1 was expressed at higher level in roots, leaves, and lateral roots than in stems and seeds. The expression of PgMYB1 was up-regulated by abscisic acid, salicylic acid, NaCl, and cold (chilling), and down-regulated by methyl jasmonate. These results suggest that PgMYB1 might be involved in responding to environmental stresses and hormones. © The Author 2015. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

Marine Invasion in the Mediterranean Sea: The Role of Abiotic Factors When There Is No Biological Resistance

PubMed Central

2012-01-01

The tropical red alga Womersleyella setacea (Rhodomelaceae, Rhodophyta) is causing increasing concern in the Mediterranean Sea because of its invasive behavior. After its introduction it has colonized most Mediterranean areas, but the mechanism underlying its acclimatization and invasion process remains unknown. To understand this process, we decided i) to assess in situ the seasonal biomass and phenological patterns of populations inhabiting the Mediterranean Sea in relation to the main environmental factors, and ii) to experimentally determine if the tolerance of W. setacea to different light and temperature conditions can explain its colonization success, as well as its bathymetric distribution range. The bathymetric distribution, biomass, and phenology of W. setacea were studied at two localities, and related to irradiance and temperature values recorded in situ. Laboratory experiments were set up to study survival, growth and reproduction under contrasting light and temperature conditions in the short, mid, and long term.Results showed that, in the studied area, the bathymetric distribution of W. setacea is restricted to a depth belt between 25 and 40 m deep, reaching maximum biomass values (126 g dw m−2) at 30 m depth. In concordance, although in the short term W. setacea survived and grew in a large range of environmental conditions, its life requirements for the mid and long term were dim light levels and low temperatures. Biomass of Womersleyella setacea did not show any clear seasonal pattern, though minimum values were reported in spring. Reproductive structures were always absent. Bearing in mind that no herbivores feed on Womersleyella setacea and that its thermal preferences are more characteristic of temperate than of tropical seaweeds, low light (50 µmol photon m−2 s−1) and low temperature (12°C) levels are critical for W. setacea survival and growth, thus probably determining its spread and bathymetric distribution across the Mediterranean

The Role of Plant Abiotic Factors on the Interactions Between Cnaphalocrocis medinalis (Lepidoptera: Crambidae) and its Host Plant.

PubMed

Tu, Kun-Yu; Tsai, Shin-Fu; Guo, Tzu-Wei; Lin, Hou-Ho; Yang, Zhi-Wei; Liao, Chung-Ta; Chuang, Wen-Po

2018-05-12

Atmospheric temperature increases along with increasing atmospheric CO2 concentration. This is a major concern for agroecosystems. Although the impact of an elevated temperature or increased CO2 has been widely reported, there are few studies investigating the combined effect of these two environmental factors on plant-insect interactions. In this study, plant responses (phenological traits, defensive enzyme activity, secondary compounds, defense-related gene expression and phytohormone) of Cnaphalocrocis medinalis (Guenée) (Lepidoptera: Pyralidae) -susceptible and resistant rice under various conditions (environment, soil type, variety, C. medinalis infestation) were used to examine the rice-C. medinalis interaction. The results showed that leaf chlorophyll content and trichome density in rice were variety-dependent. Plant defensive enzyme activities were affected environment, variety, or C. medinalis infestation. In addition, total phenolic content of rice leaves was decreased by elevated CO2 and temperature and C. medinalis infestation. Defense-related gene expression patterns were affected by environment, soil type, or C. medinalis infestation. Abscisic acid and salicylic acid content were decreased by C. medinalis infestation. However, jasmonic acid content was increased by C. medinalis infestation. Furthermore, under elevated CO2 and temperature, rice plants had higher abscisic acid content than plants under ambient conditions. The adult morphological traits of C. medinalis also were affected by environment. Under elevated CO2 and temperature, C. medinalis adults had greater body length in the second and third generations. Taken together these results indicated that elevated CO2 and temperature not only affects plants but also the specialized insects that feed on them.

Diagnosing Abiotic Degradation

EPA Science Inventory

The abiotic degradation of chlorinated solvents in ground water can be difficult to diagnose. Under current practice, most of the “evidence” is negative; specifically the apparent disappearance of chlorinated solvents with an accumulation of vinyl chloride, ethane, ethylene, or ...

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,…

Human Factors Influencing Decision Making

DTIC Science & Technology

1998-07-01

than General Grant. Van Fleet and Yukl 28 (1986): "A study of World War I veterans suggested that the presence of hunger , thirst, fatigue, ignorance of...Greenwood Press, New York, 1987, pp. 167-184. 27 Fishburne, F.J. " Neuropsychological applications in military settings." In Reuven Gal and A. David...suggested that the presence of hunger , thirst, fatigue, ignorance of plans and idleness increases the danger from fear. The most important factors in

Factors influencing perceived angular velocity

NASA Technical Reports Server (NTRS)

Kaiser, Mary K.; Calderone, Jack B.

1991-01-01

Angular velocity perception is examined for rotations both in depth and in the image plane and the influence of several object properties on this motion parameter is explored. Two major object properties are considered, namely, texture density which determines the rate of edge transitions for rotations in depth, i.e., the number of texture elements that pass an object's boundary per unit of time, and object size which determines the tangential linear velocities and 2D image velocities of texture elements for a given angular velocity. Results of experiments show that edge-transition rate biased angular velocity estimates only when edges were highly salient. Element velocities had an impact on perceived angular velocity; this bias was associated with 2D image velocity rather than 3D tangential velocity. Despite these biases judgements were most strongly determined by the true angular velocity. Sensitivity to this higher order motion parameter appeared to be good for rotations both in depth (y-axis) and parallel to the line of sight (z-axis).

Factors that influence women's health in Tanzania.

PubMed

Lugina, H I

1994-01-01

A descriptive account of factors that influence women's health in Tanzania is given. The social and cultural processes that enhance or undermine women's health are emphasized. Recommendations for changes to improve women's health are made.

Factors Influencing Title VII Bilingual Program Institutionalization.

ERIC Educational Resources Information Center

Lewis, Gerald R.; And Others

1985-01-01

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

Abiotic factors affect the recruitment and biomass of perennial grass and evergreen shrub seedlings in denuded areas of Patagonian Monte rangelands.

PubMed

Bosco, Tomás; Bertiller, Mónica Beatriz; Carrera, Analía Lorena

2018-07-15

recruitment of the small-seeded perennial grasses and A. lampa. Ambient UV had negative effects on seedling biomass of perennial grasses. These complex relationships among abiotic factors and seed and plant traits should be taken into account when planning management actions after disturbances. Copyright © 2018 Elsevier Ltd. All rights reserved.

Abiotic Supramolecular Systems

DTIC Science & Technology

2011-05-02

REPORT Abiotic Supramolecular Systems 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: The goal of this research project was to develop new concepts for the...decision, unless so designated by other documentation. 12. DISTRIBUTION AVAILIBILITY STATEMENT Approved for Public Release; Distribution Unlimited UU...9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 6. AUTHORS 7. PERFORMING ORGANIZATION NAMES AND ADDRESSES U.S. Army Research Office P.O

Biotic and abiotic factors regulating forest floor CO2 flux across a range of forest age classes in the southern Appalachians

Treesearch

James M. Vose; Paul V. Bolstad

2007-01-01

We measured forest floor CO2 flux in three age classes of forest in the southern Appalachians: 20-year-old, 85-year-old, and old-growth. Our objectives were to quantify differences in forest floor CO2 flux among age classes, and determine the relative importance of abiotic and biotic driving variables. Forest floor CO

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

A Dehydration-Induced Eukaryotic Translation Initiation Factor iso4G Identified in a Slow Wilting Soybean Cultivar Enhances Abiotic Stress Tolerance in Arabidopsis.

PubMed

Gallino, Juan P; Ruibal, Cecilia; Casaretto, Esteban; Fleitas, Andrea L; Bonnecarrère, Victoria; Borsani, Omar; Vidal, Sabina

2018-01-01

Water is usually the main limiting factor for soybean productivity worldwide and yet advances in genetic improvement for drought resistance in this crop are still limited. In the present study, we investigated the physiological and molecular responses to drought in two soybean contrasting genotypes, a slow wilting N7001 and a drought sensitive TJS2049 cultivars. Measurements of stomatal conductance, carbon isotope ratios and accumulated dry matter showed that N7001 responds to drought by employing mechanisms resulting in a more efficient water use than TJS2049. To provide an insight into the molecular mechanisms that these cultivars employ to deal with water stress, their early and late transcriptional responses to drought were analyzed by suppression subtractive hybridization. A number of differentially regulated genes from N7001 were identified and their expression pattern was compared between in this genotype and TJS2049. Overall, the data set indicated that N7001 responds to drought earlier than TJ2049 by up-regulating a larger number of genes, most of them encoding proteins with regulatory and signaling functions. The data supports the idea that at least some of the phenotypic differences between slow wilting and drought sensitive plants may rely on the regulation of the level and timing of expression of specific genes. One of the genes that exhibited a marked N7001-specific drought induction profile encoded a eukaryotic translation initiation factor iso4G ( GmeIFiso4G-1a ). GmeIFiso4G-1a is one of four members of this protein family in soybean, all of them sharing high sequence identity with each other. In silico analysis of GmeIFiso4G-1 promoter sequences suggested a possible functional specialization between distinct family members, which can attain differences at the transcriptional level. Conditional overexpression of GmeIFiso4G-1a in Arabidopsis conferred the transgenic plants increased tolerance to osmotic, salt, drought and low temperature stress

A Dehydration-Induced Eukaryotic Translation Initiation Factor iso4G Identified in a Slow Wilting Soybean Cultivar Enhances Abiotic Stress Tolerance in Arabidopsis

PubMed Central

Gallino, Juan P.; Ruibal, Cecilia; Casaretto, Esteban; Fleitas, Andrea L.; Bonnecarrère, Victoria; Borsani, Omar; Vidal, Sabina

2018-01-01

Water is usually the main limiting factor for soybean productivity worldwide and yet advances in genetic improvement for drought resistance in this crop are still limited. In the present study, we investigated the physiological and molecular responses to drought in two soybean contrasting genotypes, a slow wilting N7001 and a drought sensitive TJS2049 cultivars. Measurements of stomatal conductance, carbon isotope ratios and accumulated dry matter showed that N7001 responds to drought by employing mechanisms resulting in a more efficient water use than TJS2049. To provide an insight into the molecular mechanisms that these cultivars employ to deal with water stress, their early and late transcriptional responses to drought were analyzed by suppression subtractive hybridization. A number of differentially regulated genes from N7001 were identified and their expression pattern was compared between in this genotype and TJS2049. Overall, the data set indicated that N7001 responds to drought earlier than TJ2049 by up-regulating a larger number of genes, most of them encoding proteins with regulatory and signaling functions. The data supports the idea that at least some of the phenotypic differences between slow wilting and drought sensitive plants may rely on the regulation of the level and timing of expression of specific genes. One of the genes that exhibited a marked N7001-specific drought induction profile encoded a eukaryotic translation initiation factor iso4G (GmeIFiso4G-1a). GmeIFiso4G-1a is one of four members of this protein family in soybean, all of them sharing high sequence identity with each other. In silico analysis of GmeIFiso4G-1 promoter sequences suggested a possible functional specialization between distinct family members, which can attain differences at the transcriptional level. Conditional overexpression of GmeIFiso4G-1a in Arabidopsis conferred the transgenic plants increased tolerance to osmotic, salt, drought and low temperature stress

Using vegetation model-to-data comparisons to test the role of abiotic factors in the Neogene and Quaternary origins of modern C4 grasslands

NASA Astrophysics Data System (ADS)

Fox, D. L.; Strömberg, C.; Pau, S.; Taylor, L.; Lehmann, C.; Osborne, C.; Beerling, D. J.; Still, C. J.

2014-12-01

) of multiple plant functional types (C3 and C4 grasses, evergreen and deciduous trees). Statistical comparisons of the isotopic and paleobotanical databases with the paleoclimate and vegetation model outputs allows us to assess the possible role of abiotic factors in the evolution of modern C4 grasslands during the late Neogene.

A hierarchy of factors influence discontinuous gas exchange in the grasshopper Paracinema tricolor (Orthoptera: Acrididae).

PubMed

Groenewald, Berlizé; Chown, Steven L; Terblanche, John S

2014-10-01

The evolutionary origin and maintenance of discontinuous gas exchange (DGE) in tracheate arthropods are poorly understood and highly controversial. We investigated prioritization of abiotic factors in the gas exchange control cascade by examining oxygen, water and haemolymph pH regulation in the grasshopper Paracinema tricolor. Using a full-factorial design, grasshoppers were acclimated to hypoxic or hyperoxic (5% O2, 40% O2) gas conditions, or dehydrated or hydrated, whereafter their CO2 release was measured under a range of O2 and relative humidity (RH) conditions (5%, 21%, 40% O2 and 5%, 60%, 90% RH). DGE was significantly less common in grasshoppers acclimated to dehydrating conditions compared with the other acclimations (hypoxia, 98%; hyperoxia, 100%; hydrated, 100%; dehydrated, 67%). Acclimation to dehydrating conditions resulted in a significant decrease in haemolymph pH from 7.0±0.3 to 6.6±0.1 (mean ± s.d., P=0.018) and also significantly increased the open (O)-phase duration under 5% O2 treatment conditions (5% O2, 44.1±29.3 min; 40% O2, 15.8±8.0 min; 5% RH, 17.8±1.3 min; 60% RH, 24.0±9.7 min; 90% RH, 20.6±8.9 min). The observed acidosis could potentially explain the extension of the O-phase under low RH conditions, when it would perhaps seem more useful to reduce the O-phase to lower respiratory water loss. The results confirm that DGE occurrence and modulation are affected by multiple abiotic factors. A hierarchical framework for abiotic factors influencing DGE is proposed in which the following stressors are prioritized in decreasing order of importance: oxygen supply, CO2 excretion and pH modulation, oxidative damage protection and water savings. © 2014. Published by The Company of Biologists Ltd.

Factors potentially influencing aminoglycoside use and expenditure

SciTech Connect

DiPiro, J.T.; Kilsdonk, G.F.; Amerson, A.B.

1982-07-01

Factors that may have influenced aminoglycoside use and expenditure in one hospital were examined. Factors that were evaluated as to their influence on aminoglycoside-use patterns were: (1) formulary status; (2) bacterial susceptibility patterns; (3) identified or perceived differences in toxicity; (4) changes in patient population; (5) price paid by the hospital for aminoglycosides; (6) distribution of newsletters or memoranda; (7) advertising and detailing; and (8) pharmacy policies. For FY 1976-77 to 1979-80, the largest proportion of aminoglycoside expense was for gentamicin. During FY 1980-81, the expenditure for gentamicin decreased and tobramycin accounted for the largest proportion of total expenditure. Monthlymore » gentamicin use decreased 20% during FY 1980-81 from the previous year. Tobramycin use increased from January 1979 to November 1980 and decreased from December 1980 to June 1981. Kanamycin use and amikacin use were fairly constant during the study period. Based on temporal relationships, the following factors appeared to influence aminoglycoside use and expenditure: (1) a study conducted at the institution from June 1977 to June 1979 comparing gentamicin and tobramycin nephrotoxicity; (2) a comparative nephrotoxicity study published in a widely circulated medical journal in May 1980; and (3) an intramural newsletter and memorandum distributed in March 1981 encouraging selective aminoglycoside use. The identification of factors that potentially influenced aminoglycoside use can be used to anticipate the future impact of similar events and to devise strategies to influence antimicrobial use.« less

Monthly Distribution of Phlebotomine Sand Flies, and Biotic and Abiotic Factors Related to Their Abundance, in an Urban Area to Which Visceral Leishmaniasis Is Endemic in Corumbá, Brazil.

PubMed

Falcão de Oliveira, Everton; Casaril, Aline Etelvina; Fernandes, Wagner Souza; Ravanelli, Michelle de Saboya; Medeiros, Márcio José de; Gamarra, Roberto Macedo; Paranhos Filho, Antônio Conceição; Oshiro, Elisa Teruya; Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi

2016-01-01

The monthly distribution and abundance of sand flies are influenced by both biotic and abiotic factors. The present study aimed to evaluate the seasonal distribution of sand flies and the relation between their abundance and environmental parameters, including vegetation and climate. This study was conducted over a 2-year period (April 2012 to March 2014). Monthly distribution was evaluated through the weekly deployment of CDC light traps in the peridomicile area of 5 residences in an urban area of the municipality of Corumbá in the State of Mato Grosso do Sul, Brazil. Meteorological data were obtained from the Mato Grosso do Sul Center for Weather, Climate, and Water Resources. The spectral indices were calculated based on spatial resolution images (GeoEye) and the percentage of vegetal coverage. Differences in the abundance of sand flies among the collection sites were assessed using the Kruskal-Wallis test, and the strength of correlations between environmental variables was determined by calculating Spearman's correlation coefficients. Lutzomyia cruzi, Lu. forattinii, and Evandromyia corumbaensis were the most frequently found species. Although no significant association was found among these sand fly species and the tested environmental variables (vegetation and climate), high population peaks were found during the rainy season, whereas low peaks were observed in the dry season. The monthly distribution of sand flies was primarily determined by Lu. cruzi, which accounted for 93.94% of the specimens collected each month throughout the experimental period. The fact that sand flies were detected year-round indicates a continuous risk of infection to humans, demonstrating the need for targeted management and education programs.

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.

Factors influencing woodlands of southwestern North Dakota

Treesearch

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

1987-01-01

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

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…

Factors influencing laser cutting of wood

Treesearch

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

1986-01-01

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

Factors Influencing Intrinsic Motivation towards Physical Activity.

ERIC Educational Resources Information Center

Rutherford, William J.; And Others

1992-01-01

Study examined factors that influenced intrinsic motivation toward physical activity in 60 adult males who completed questionnaires and physical fitness tests. Results showed that performance information given immediately after task performance increased perceived competence and intrinsic motivation levels toward exercise of individuals with…

Factors Influencing Teaching Choice in Turkey

ERIC Educational Resources Information Center

Kilinc, Ahmet; Watt, Helen M. G.; Richardson, Paul W.

2012-01-01

Why choose to become a teacher in Turkey? The authors examined motivations and perceptions among preservice teachers (N = 1577) encompassing early childhood, primary and secondary education. The Factors Influencing Teaching Choice (FIT-Choice) instrument was translated into Turkish and its construct validity and reliability assessed. Altruistic…

Exploring Factors That Influence Quality Literature Circles

ERIC Educational Resources Information Center

Young, Chase; Mohr, Kathleen A. J.

2018-01-01

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

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

Social Factors Influencing Child Health in Ghana.

PubMed

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

2016-01-01

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

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.

Uncovering Factors Influencing Interpersonal Health Communication

PubMed Central

Donné, Lennie; Jansen, Carel; Hoeks, John

2017-01-01

Talking to friends, family, or peers about health issues might, among other things, increase knowledge of social norms and feelings of self-efficacy in adopting a healthier lifestyle. We often see interpersonal health communication as an important mediating factor in the effects of health campaigns on health behavior. No research has been done so far, however, on factors that influence whether and how people talk about health issues without being exposed to a health campaign first. In this exploratory study, we interviewed 12 participants about their communication behavior concerning six different health themes, like smoking and exercising. The results suggest that at least four types of interpersonal health communication can be distinguished, each influenced by different factors, like conversational partner and objective of the conversation. Future research should take this diversity of interpersonal health communication into account, and focus on designing health campaigns that aim to trigger dialogue within target populations. PMID:28660238

Consideration of Real World Factors Influencing Greenhouse ...

EPA Pesticide Factsheets

Discuss a variety of factors that influence the simulated fuel economy and GHG emissions that are often overlooked and updates made to ALPHA based on actual benchmarking data observed across a range of vehicles and transmissions. ALPHA model calibration is also examined, focusing on developing generic calibrations for driver behavior, transmission gear selection and torque converter lockup. In addition, show the derivation of correction factors needed to estimate cold start emission results. To provide an overview of the ALPHA tool with additional focus on recent updates by presenting the approach for validating and calibrating ALPHA to match particular vehicles in a general sense, then by looking at the individual losses, and calibration factors likely to influence fuel economy.

Influence of organizational factors on safety

SciTech Connect

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

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 ofmore » 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.« less

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.

Factors that influence nurses' customer orientation.

PubMed

Darby, D N; Daniel, K

1999-09-01

Hospital care mostly involves complex processes that are continuously adjusted to match individual client needs. As most patients cannot evaluate the technology used, they focus on personal interactions with care providers when making judgements about the care received. Nurses are the care team members that primarily provide ongoing care. This study aims to further understand factors that influence the way nursing staff relate to their patients. A model is presented of the contextual and self-perceptual factors that influence the level of customer/client orientation of nursing services in an Australian hospital setting along with details of a quantitative study. Nurses completed an anonymous questionnaire, which was then mailed directly to the researchers. Analysis of the data included factor analysis, regression and path analysis. The results show that contextual elements such as management commitment to service quality and self-perceptual factors such as role stress impact on the nurses' client service orientation. However, the variables being studied commonly have both direct and indirect effects with feelings about commitment to the organization having a notable mediating influence. The scales adapted from use in other industries are able to measure the perceptual and outcome variables in a health institutional setting. The managerial implications are that both a comprehensive programme of organizational culture and individual staff member development is needed if an enhanced customer orientation and the consequent improvement in client satisfaction with nursing care is to occur.

Genome-wide identification and characterization of the Populus WRKY transcription factor family and analysis of their expression in response to biotic and abiotic stresses

PubMed Central

Jiang, Yuanzhong; Duan, Yanjiao; Yin, Jia; Ye, Shenglong; Zhu, Jingru; Zhang, Faqi; Lu, Wanxiang; Fan, Di; Luo, Keming

2014-01-01

WRKY proteins are a large family of regulators involved in various developmental and physiological processes, especially in coping with diverse biotic and abiotic stresses. In this study, 100 putative PtrWRKY genes encoded the proteins contained in the complete WRKY domain in Populus. Phylogenetic analysis revealed that the members of this superfamily among poplar, Arabidopsis, and other species were divided into three groups with several subgroups based on the structures of the WRKY protein sequences. Various cis-acting elements related to stress and defence responses were found in the promoter regions of PtrWRKY genes by promoter analysis. High-throughput transcriptomic analyses identified that 61 of the PtrWRKY genes were induced by biotic and abiotic treatments, such as Marssonina brunnea, salicylic acid (SA), methyl jasmonate (MeJA), wounding, cold, and salinity. Among these PtrWRKY genes, transcripts of 46 selected genes were observed in different tissues, including roots, stems, and leaves. Quantitative RT-PCR analysis further confirmed the induced expression of 18 PtrWRKY genes by one or more stress treatments. The overexpression of an SA-inducible gene, PtrWRKY89, accelerated expression of PR protein genes and improved resistance to pathogens in transgenic poplar, suggesting that PtrWRKY89 is a regulator of an SA-dependent defence-signalling pathway in poplar. Taken together, our results provided significant information for improving the resistance and stress tolerance of woody plants. PMID:25249073

[Factors influencing nurses' organizational citizenship behavior].

PubMed

Park, Junhee; Yun, Eunkyung; Han, Sangsook

2009-08-01

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

Abiotic factors influencing embryonic development, egg hatching, and larval orientation in the reindeer warble fly, Hypoderma tarandi.

PubMed

Karter, A J; Folstad, I; Anderson, J R

1992-10-01

Wild-caught, tethered females of the reindeer warble fly, Hypoderma tarandi (L.) (= Oedemagena tarandi (L.)), (Diptera, Oestridae) were stimulated to oviposit on hairs of a reindeer hide. Newly laid eggs incubated at constant temperatures and relative humidities hatched within 3 days to 2 weeks, depending on the experimental conditions. Over a range of 7-40 degrees C, hatching only occurred between 20 and 37 degrees C. Eggs held at 100% relative humidity had lower hatchability and longer time to hatch relative to eggs held at 77% relative humidity. The average number of degree-days for hatching was 50.35. Between 20 and 33 degrees C there was a temperature-dependent linear trend in developmental rate, and the proportion of eggs hatching was highest, and least variable, at the mid-temperature ranges. The temperature range found in the natural host micro-habitat where H. tarandi commonly affix their eggs (close to the skin at the base of a host hair) was consistent with the experimental temperature treatments that produced the highest hatching rate. Newly emerged larvae displayed positive thermotaxis, while showing no phototaxic or geotaxic behaviour. Results indicate that constraints of the host environment, coupled with temperature-dependent hatching success, may impose a selective pressure on oviposition behaviour.

Factors influencing micronutrient bioavailability in biofortified crops.

PubMed

Bechoff, Aurélie; Dhuique-Mayer, Claudie

2017-02-01

Dietary and human factors have been found to be the major factors influencing the bioavailability of micronutrients, such as provitamin A carotenoid (pVAC), iron, and zinc, in biofortified crops. Dietary factors are related to food matrix structure and composition. Processing can improve pVAC bioavailability by disrupting the food matrix but can also result in carotenoid losses. By degrading antinutrients, such as phytate, processing can also enhance mineral bioavailability. In in vivo interventions, biofortified crops have been shown to be overall efficacious in reducing micronutrient deficiency, with bioconversion factors varying between 2.3:1 and 10.4:1 for trans-β-carotene and amounts of iron and zinc absorbed varying between 0.7 and 1.1 mg/day and 1.1 and 2.1 mg/day, respectively. Micronutrient bioavailability was dependent on the crop type and the presence of fat for pVACs and on antinutrients for minerals. In addition to dietary factors, human factors, such as inflammation and disease, can affect micronutrient status. Understanding the interactions between micronutrients is also essential, for example, the synergic effect of iron and pVACs or the competitive effect of iron and zinc. Future efficacy trials should consider human status and genetic polymorphisms linked to interindividual variations. © 2016 New York Academy of Sciences.

Genome-wide identification and characterization of the Populus WRKY transcription factor family and analysis of their expression in response to biotic and abiotic stresses.

PubMed

Jiang, Yuanzhong; Duan, Yanjiao; Yin, Jia; Ye, Shenglong; Zhu, Jingru; Zhang, Faqi; Lu, Wanxiang; Fan, Di; Luo, Keming

2014-12-01

WRKY proteins are a large family of regulators involved in various developmental and physiological processes, especially in coping with diverse biotic and abiotic stresses. In this study, 100 putative PtrWRKY genes encoded the proteins contained in the complete WRKY domain in Populus. Phylogenetic analysis revealed that the members of this superfamily among poplar, Arabidopsis, and other species were divided into three groups with several subgroups based on the structures of the WRKY protein sequences. Various cis-acting elements related to stress and defence responses were found in the promoter regions of PtrWRKY genes by promoter analysis. High-throughput transcriptomic analyses identified that 61 of the PtrWRKY genes were induced by biotic and abiotic treatments, such as Marssonina brunnea, salicylic acid (SA), methyl jasmonate (MeJA), wounding, cold, and salinity. Among these PtrWRKY genes, transcripts of 46 selected genes were observed in different tissues, including roots, stems, and leaves. Quantitative RT-PCR analysis further confirmed the induced expression of 18 PtrWRKY genes by one or more stress treatments. The overexpression of an SA-inducible gene, PtrWRKY89, accelerated expression of PR protein genes and improved resistance to pathogens in transgenic poplar, suggesting that PtrWRKY89 is a regulator of an SA-dependent defence-signalling pathway in poplar. Taken together, our results provided significant information for improving the resistance and stress tolerance of woody plants. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recent Molecular Advances on Downstream Plant Responses to Abiotic Stress

PubMed Central

dos Reis, Sávio Pinho; Lima, Aline Medeiros; de Souza, Cláudia Regina Batista

2012-01-01

Abiotic stresses such as extremes of temperature and pH, high salinity and drought, comprise some of the major factors causing extensive losses to crop production worldwide. Understanding how plants respond and adapt at cellular and molecular levels to continuous environmental changes is a pre-requisite for the generation of resistant or tolerant plants to abiotic stresses. In this review we aimed to present the recent advances on mechanisms of downstream plant responses to abiotic stresses and the use of stress-related genes in the development of genetically engineered crops. PMID:22942725

[New nurse turnover intention and influencing factors].

PubMed

Han, Sang Sook; Sohn, In Soon; Kim, Nam Eun

2009-12-01

The study was done to identify turnover intention in new nurses according to characteristics of the nurses and other factors affecting turnover and to provide data to set up a strategy to reduce the turnover. Data were collected from 1,077 new nurses who had less than 12 months employment experience and worked in one of 188 hospitals. Eight research instruments were used. Data analysis was done using SPSS WIN 15.0 program. Several factors influence new nurse turnover intention. The average score for turnover intention was 2.12. The scores for subscales were self efficacy, 3.76, nursing performance, 3.90, job satisfaction, 2.09, organization commitment, 1.28, stress, 1.32, burnout, 2.82 and nursing organizational culture, 3.29. Turnover intention was related to self efficacy, nursing performance, job satisfaction, organization commitment, stress, burnout, nursing organizational culture, duration of in-class training, duration of on the job training, number of hospital beds, length of employment and duration of employment in current workplace. The predicting factors for turnover intention were burnout, stress, duration of employment in the current workplace, self efficacy and nursing performance. Those factors explained 51.6% of turnover intention. New nurse turnover intention can be reduced by mitigating the factors affecting this intention.

Factors influencing the incidence of maxillofacial fractures.

PubMed

Chrcanovic, Bruno Ramos

2012-03-01

Maxillofacial injuries occur in a significant proportion of trauma patients. Trauma causes considerable economic expense due to procedural costs, the time a patient is off work, and the associated loss of income. For these reasons, it is an important health and economic issue. The aim of this study is to discuss the factors that may influence the incidence of maxillofacial fractures. As it is necessary to determine trends to help guide the development of new methods of injury prevention, preventative measures are also discussed. An electronic search was undertaken in March 2011, including articles published between 1980 and 2011 with the terms "facial fractures" and "maxillofacial fractures" in the title. The texts of epidemiological studies were reviewed in order to identify factors that may influence the incidence of maxillofacial fractures. From the selected articles, ten factors were identified: age, gender, geographic region and cultural aspects, socioeconomic status, temporal and climatic influence, use of alcohol and drugs, compliance with road traffic legislation, domestic violence, osteoporosis, and etiology of the maxillofacial trauma. Care of injured patients should include not only management of the acute phase, but also combine preventive programs and interventional programs aimed at reducing the incidence of maxillofacial fractures. Therefore, there is a need to ensure strict compliance of traffic rules and regulations, implement improvement in automotive safety devices, organize prevention programs to minimize assaults, implement school education in alcohol abuse and handling potentially hostile situations (especially for men), improve protection during sporting activities, and legislate wearing of protective headgear in workers. Preventive strategies remain the cheapest way to reduce direct and indirect costs of the sequelae of trauma. Societal attitudes and behaviors must be modified before a significant reduction in the incidence of maxillofacial

Establishment of non-native plant species after wildfires: Effects of fuel treatments, abiotic and biotic factors, and post-fire grass seeding treatments

USGS Publications Warehouse

Hunter, M.E.; Omi, Philip N.; Martinson, E.J.; Chong, G.W.

2006-01-01

Establishment and spread of non-native species following wildfires can pose threats to long-term native plant recovery. Factors such as disturbance severity, resource availability, and propagule pressure may influence where non-native species establish in burned areas. In addition, pre- and post-fire management activities may influence the likelihood of non-native species establishment. In the present study we examine the establishment of non-native species after wildfires in relation to native species richness, fire severity, dominant native plant cover, resource availability, and pre- and post-fire management actions (fuel treatments and post-fire rehabilitation treatments). We used an information-theoretic approach to compare alternative hypotheses. We analysed post-fire effects at multiple scales at three wildfires in Colorado and New Mexico. For large and small spatial scales at all fires, fire severity was the most consistent predictor of non-native species cover. Non-native species cover was also correlated with high native species richness, low native dominant species cover, and high seeded grass cover. There was a positive, but non-significant, association of non-native species with fuel-treated areas at one wildfire. While there may be some potential for fuels treatments to promote non-native species establishment, wildfire and post-fire seeding treatments seem to have a larger impact on non-native species. ?? IAWF 2006.

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.

Factors influencing variation in dentist service rates.

PubMed

Grembowski, D; Milgrom, P; Fiset, L

1990-01-01

In the previous article, we calculated dentist service rates for 200 general dentists based on a homogeneous, well-educated, upper-middle-class population of patients. Wide variations in the rates were detected. In this analysis, factors influencing variation in the rates were identified. Variation in rates for categories of dental services was explained by practice characteristics, patient exposure to fluoridated water supplies, and non-price competition in the dental market. Rates were greatest in large, busy practices in markets with high fees. Older practices consistently had lower rates across services. As a whole, these variables explained between 5 and 30 percent of the variation in the rates.

Abiotic tooth enamel

NASA Astrophysics Data System (ADS)

Yeom, Bongjun; Sain, Trisha; Lacevic, Naida; Bukharina, Daria; Cha, Sang-Ho; Waas, Anthony M.; Arruda, Ellen M.; Kotov, Nicholas A.

2017-03-01

Tooth enamel comprises parallel microscale and nanoscale ceramic columns or prisms interlaced with a soft protein matrix. This structural motif is unusually consistent across all species from all geological eras. Such invariability—especially when juxtaposed with the diversity of other tissues—suggests the existence of a functional basis. Here we performed ex vivo replication of enamel-inspired columnar nanocomposites by sequential growth of zinc oxide nanowire carpets followed by layer-by-layer deposition of a polymeric matrix around these. We show that the mechanical properties of these nanocomposites, including hardness, are comparable to those of enamel despite the nanocomposites having a smaller hard-phase content. Our abiotic enamels have viscoelastic figures of merit (VFOM) and weight-adjusted VFOM that are similar to, or higher than, those of natural tooth enamels—we achieve values that exceed the traditional materials limits of 0.6 and 0.8, respectively. VFOM values describe resistance to vibrational damage, and our columnar composites demonstrate that light-weight materials of unusually high resistance to structural damage from shocks, environmental vibrations and oscillatory stress can be made using biomimetic design. The previously inaccessible combinations of high stiffness, damping and light weight that we achieve in these layer-by-layer composites are attributed to efficient energy dissipation in the interfacial portion of the organic phase. The in vivo contribution of this interfacial portion to macroscale deformations along the tooth’s normal is maximized when the architecture is columnar, suggesting an evolutionary advantage of the columnar motif in the enamel of living species. We expect our findings to apply to all columnar composites and to lead to the development of high-performance load-bearing materials.

Automation bias: empirical results assessing influencing factors.

PubMed

Goddard, Kate; Roudsari, Abdul; Wyatt, Jeremy C

2014-05-01

To investigate the rate of automation bias - the propensity of people to over rely on automated advice and the factors associated with it. Tested factors were attitudinal - trust and confidence, non-attitudinal - decision support experience and clinical experience, and environmental - task difficulty. The paradigm of simulated decision support advice within a prescribing context was used. The study employed within participant before-after design, whereby 26 UK NHS General Practitioners were shown 20 hypothetical prescribing scenarios with prevalidated correct and incorrect answers - advice was incorrect in 6 scenarios. They were asked to prescribe for each case, followed by being shown simulated advice. Participants were then asked whether they wished to change their prescription, and the post-advice prescription was recorded. Rate of overall decision switching was captured. Automation bias was measured by negative consultations - correct to incorrect prescription switching. Participants changed prescriptions in 22.5% of scenarios. The pre-advice accuracy rate of the clinicians was 50.38%, which improved to 58.27% post-advice. The CDSS improved the decision accuracy in 13.1% of prescribing cases. The rate of automation bias, as measured by decision switches from correct pre-advice, to incorrect post-advice was 5.2% of all cases - a net improvement of 8%. More immediate factors such as trust in the specific CDSS, decision confidence, and task difficulty influenced rate of decision switching. Lower clinical experience was associated with more decision switching. Age, DSS experience and trust in CDSS generally were not significantly associated with decision switching. This study adds to the literature surrounding automation bias in terms of its potential frequency and influencing factors. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Factors influencing global antiretroviral procurement prices.

PubMed

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

2009-11-18

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

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

Factors that influence nurses' job satisfaction.

PubMed

Ma, Chen-Chung; Samuels, Michael E; Alexander, Judith W

2003-05-01

To examine factors affecting the job satisfaction of registered nurses (RNs). A growing recognition of job dissatisfaction among RNs in South Carolina hospitals has contributed to current problems with recruitment and retention. If administrators identify factors influencing RNs' job satisfaction in hospitals and implement strategies to address these factors, RN turnover rates will decrease and recruiting and retention rates will increase. A cross-sectional study of secondary data was designed to identify the individual, work, and geographic factors that impact nursing job satisfaction at the state level. A 27-question self-administered survey was sent to 17,500 RNs in South Carolina with postage-paid envelopes for their responses. Surveys from 3472 nurses were completed anonymously. Univariate statistics were used to describe the study sample. One-way and multivariable Analysis of Variance were used to determine which variables contributed the most to job satisfaction. For about two thirds of the RNs, job satisfaction remained the same or had lessened over the past 2 years. In addition, statistically significant differences were found between job satisfaction and years of service, job position, hospital retirement plan, and geographic area. The findings have implications for nurse managers and hospital administrators for planning and implementing effective health policies that will meet the unique needs of their staffs and organizations. Such research is particularly relevant in this difficult time of nursing shortages throughout the healthcare industry.

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

Audit in general practice: factors influencing participation.

PubMed Central

Baker, R.; Robertson, N.; Farooqi, A.

1995-01-01

OBJECTIVE--To identify the factors influencing participation in a single topic audit initiated by a medical audit advisory group. DESIGN--Interview and questionnaire survey of general practitioners who had been invited to take part in an audit of vitamin B-12. SETTING--All 147 general practices in Leicestershire. MAIN OUTCOME MEASURES--Aspects of structure, attitude, and behaviour that influenced participation or non-participation. RESULTS--75 practices completed the audit, 49 withdrew after initial agreement, and 23 refused to take part at the outset. Participants were more likely than those who refused to view the advisory group as useful or a threat and to have positive thoughts about audit but less likely to have previously undertaken audit entailing implementation of change. Participants were more likely than those who withdrew to have positive thoughts about audit and to have discussed whether to take part within the practice but were less likely to view the advisory group as useful. The most common reason given for withdrawal was lack of time. CONCLUSIONS--Participation was influenced by attitudes towards audit in general and the advisory group in particular and by aspects of behaviour such as communication within the practice. Practical support and resources may help some practices undertake audit, but advisory groups must also deal with attitudes and unsatisfactory communication in practice teams. PMID:7613323

Genome-Wide Analysis of C2H2 Zinc-Finger Family Transcription Factors and Their Responses to Abiotic Stresses in Poplar (Populus trichocarpa)

PubMed Central

Liu, Quangang; Wang, Zhanchao; Xu, Xuemei; Zhang, Haizhen; Li, Chenghao

2015-01-01

Background C2H2 zinc-finger (C2H2-ZF) proteins are a large gene family in plants that participate in various aspects of normal plant growth and development, as well as in biotic and abiotic stress responses. To date, no overall analysis incorporating evolutionary history and expression profiling of the C2H2-ZF gene family in model tree species poplar (Populus trichocarpa) has been reported. Principal Findings Here, we identified 109 full-length C2H2-ZF genes in P. trichocarpa, and classified them into four groups, based on phylogenetic analysis. The 109 C2H2-ZF genes were distributed unequally on 19 P. trichocarpa linkage groups (LGs), with 39 segmental duplication events, indicating that segmental duplication has been important in the expansion of the C2H2-ZF gene family. Promoter cis-element analysis indicated that most of the C2H2-ZF genes contain phytohormone or abiotic stress-related cis-elements. The expression patterns of C2H2-ZF genes, based on heatmap analysis, suggested that C2H2-ZF genes are involved in tissue and organ development, especially root and floral development. Expression analysis based on quantitative real-time reverse transcription polymerase chain reaction indicated that C2H2-ZF genes are significantly involved in drought, heat and salt response, possibly via different mechanisms. Conclusions This study provides a thorough overview of the P. trichocarpa C2H2-ZF gene family and presents a new perspective on the evolution of this gene family. In particular, some C2H2-ZF genes may be involved in environmental stress tolerance regulation. PtrZFP2, 19 and 95 showed high expression levels in leaves and/or roots under environmental stresses. Additionally, this study provided a solid foundation for studying the biological roles of C2H2-ZF genes in Populus growth and development. These results form the basis for further investigation of the roles of these candidate genes and for future genetic engineering and gene functional studies in Populus. PMID

What factors influence cataract waiting list time?

PubMed Central

Churchill, A.; Vize, C.; Stewart, O.; Backhouse, O.

2000-01-01

AIMS—To determine whether there were any specific factors that influenced waiting list time (WLT) for patients undergoing cataract surgery.
METHODS—70 preoperative cataract patients were interviewed by one of the authors using a questionnaire to score visual acuity, coexisting ocular pathology and disabilities, threat to independent living/employment, and perceived visual handicap for detailed, gross, and driving vision. Individuals were analysed separately according to whether it was their first or second cataract operation.
RESULTS—The median WLT for first eye surgery was 9 months (n = 31) and 13 months for second eye surgery (n = 36). The WLT ranged from 2 to 25 months for first eyes and 0.25-18 months for second eyes. Where there was a perceived threat to independent living or employment the WLT was found to be significantly shorter than the median. A high overall score correlated with a shorter WLT. Surgical priority was also given to individuals with anisometropia >3 dioptres.
CONCLUSION—This study has demonstrated that there are specific factors that influence clinicians when prioritising patients for cataract surgery.

 PMID:10729304

Factors influencing tinnitus loudness and annoyance.

PubMed

Hiller, Wolfgang; Goebel, Gerhard

2006-12-01

To evaluate the 2 major components of tinnitus severity, loudness and annoyance, and their degree of dependence on characteristics of tinnitus manifestation, history, and etiology. Cross-sectional survey performed during the first months of 2004. Nonclinical population. A total of 4995 members of the German Tinnitus League. Comprehensive screening questionnaire, including the Klockhoff and Lindblom loudness grading system and the miniversion of the Tinnitus Questionnaire. A moderate correlation of 0.45 was found between tinnitus loudness and annoyance. Both factors were generally higher in men, those older than 50 years, those with binaural and centrally perceived tinnitus, those with increased noise sensitivity, and those who had continuous tinnitus without interruptions. Tinnitus that lasted 12 months or less had a stronger influence on annoyance (odds ratio [OR], 1.96) than on loudness (OR, 0.45), whereas the contrary was found for tinnitus of more than 5 years' duration (ORs, 0.72 and 2.11, respectively). Loudness and annoyance were increased in subjects with coexisting hearing loss, vertigo, and hyperacusis. The impact of hyperacusis on annoyance was clearly stronger than on loudness (ORs, 21.91 vs 9.47). Several clinical factors of tinnitus influence perceived loudness and annoyance. Both are distinguishable components of tinnitus severity.

Factors influencing endometrial thickness in postmenopausal women.

PubMed

Hebbar, S; Chaya, V; Rai, L; Ramachandran, A

2014-07-01

Cut-off values for endometrial thickness (ET) in asymptomatic postmenopausal woman have been standardized. However, there are no comprehensive studies to document how various factors can influence the ET after the age of menopause. To study the various factors influencing the ET in postmenopausal women. This was a prospective observational study. A total of 110 postmenopausal women underwent detailed history taking, clinical examination, and transvaginal scan for uterine volume and ovarian volume. The volumes were calculated by using ellipsoid formula: Width × thickness × height × 0.523. The variation in ET with respect to the influencing factors such as age, duration of menopause, parity, body mass index (BMI), medical illness like diabetes/hypertension, drugs like tamoxifen, presence of myoma, uterine volume, ovarian volume, and serum estradiol (in selected patients) were measured. Descriptive analysis was performed using SPSS software (version 16, Chicago II, USA) to obtain mean, standard deviation (SD), 95% confidence intervals (CIs) and inter quartile ranges. Comparison of means was carried out using analysis of variance. The mean (SD) age of the patients was 55.4 (6.91) years (95% CI, 54.1, 56.7). The mean (SD) age at menopause was 47.95 (3.90) years (95% CI, 47.2, 48.7) and the mean (SD) duration of menopause was 7.27 (6.65) years (95% CI, 6.01, 8.53). The mean (SD) ET was 3.8 (2.3) mm (95% CI, 3.36, 4.23). Medical illness like diabetes and hypertension did not alter the ET. ET increased as BMI increased and it was statistically significant. The presence of myoma increased uterine volume significantly and was associated with thick endometrial stripe. Similarly, whenever the ovaries were visualized and as the ovarian volume increased, there was an increase in ET. When ET was > 4 mm (n = 37), they were offered endocel, of which 16 agreed to undergo the procedure. None were found to have endometrial cancer. This study suggests that parity, BMI, presence of

Factors influencing deprescribing habits among geriatricians.

PubMed

Ní Chróinín, Danielle; Ní Chróinín, Chantelle; Beveridge, Alexander

2015-07-01

deprescribing habits among physicians managing older, frailer, cognitively impaired patients have not been well investigated. an anonymised electronic survey was disseminated to all members of an international geriatric society/local advanced trainee network (N = 930). This comprised a Likert-scale analysis of factors influencing desprescribing, and five case vignettes, detailing a patient with progressive cognitive impairment and dependency, on a background of ischaemic heart disease and hypertension. among 134 respondents (response rate 14.4%), 47.4% were female, 48.9% aged 36-50 years and 84.1% specialists (15.9% trainees). Respondents commonly rated limited life expectancy (96.2%) and cognitive impairment (84.1%) as very/extremely important to deprescribing practices. On multivariable analysis, older respondents less commonly rated functional dependency (odds ratio [OR] 0.22 per change in age category; P < 0.001) and limited life expectancy (OR 0.09, P = 0.04) important when deprescribing, while female participants (OR 3.03, P < 0.001) and trainees (versus specialists OR 14.29, P < 0.001) more often rated adherence to evidence-based guidelines important. As vignettes described increasing dependency and cognitive impairment, physicians were more likely to stop donepezil, aspirin, atorvastatin and antihypertensives (all P < 0.001 for trend). Aspirin (93.6%) and ramipril (94.1%) were most commonly deprescribed. Commonest reasons cited for deprescribing medications were 'dementia severity', followed by pill burden. in this exploratory analysis, geriatricians rated limited life expectancy and cognitive impairment very important in driving deprescribing practices. Geriatricians more often deprescribed multiple medications in the setting of advancing dependency and cognitive impairment, driven by dementia severity and pill burden concerns. Physician characteristics also influence deprescribing practices. Further exploration of factors influencing deprescribing

Factors Influencing Female Registered Nurses' Work Behavior

PubMed Central

Brewer, Carol S; Kovner, Christine T; Wu, Yow-Wu; Greene, William; Liu, Yu; Reimers, Cordelia W

2006-01-01

Objective To analyze factors that are related to whether registered nurses (RNs) work (WK) or do not work (NW) in nursing; and if the RN works, whether she works full- (FT) or part-time (PT). Data Sources Secondary data from National Sample Survey of Registered Nurses 2000 (NSSRN), the InterStudy Competitive Edge Part III Regional Market Analysis (2001), and the Area Resource File (2002). Study Design Using a cross-sectional design we tested the relationship between WK or NW and FT or PT; and demographic, job-related, and metropolitan statistical area (MSA)-level variables. Data Collection/Extraction Methods We combined the data sources noted above to produce the analytic sample of 25,471 female RNs. Principal Findings Working in nursing is not independent of working FT or PT. Age (55 and older), other family income, and prior other work experience in health care are negatively related to working as an RN. The wage is not related to working as an RN, but negatively influences FT work. Age, children, minority status, student status, employment status, other income, and some job settings have a negative impact on working FT. Previous health care work has a positive effect on whether married RNs worked. Married RNs who are more dissatisfied are less likely to work FT. A greater number of market-level factors influence FT/PT than WK/NW behavior. Conclusions An important contribution of this study is demonstrating that MSA-level variables influence RN work behavior. The market environment seems to have little effect on whether a nurse works, but is influential on how much the nurse works, and has differential effects on married versus single nurses. PMID:16704517

Factors influencing career decisions in internal medicine.

PubMed

Macdonald, C; Cawood, T

2012-08-01

Numerous factors influence career decisions for internal medicine trainees and Fellows. There is a perception that a greater emphasis is placed on work-family balance by younger physicians. To determine the characteristics of the modern internal medicine workforce and ascertain whether job flexibility is important to career decision-making. We hypothesised that factors which reflect flexibility would be highly influential in decision-making, especially for women and those with young children. A questionnaire was mailed to 250 New Zealand internal medicine trainees and Fellows. It focused on factors, including job flexibility, interest and collegial support, and included demographic details which were primarily aimed at ascertaining family responsibilities. Response rate was 54%. The majority of female physicians are the main person responsible for their children (62%), and the majority of their partners work full-time (80%). This contrasts with male physicians, of whom only 4% are the main person responsible for their children. Flexibility was found to be more influential in women, those with young children, trainees and those working in outpatient-based subspecialties. However, contrary to our original hypothesis, flexibility was not reported to be highly influential in any group, with career choice being most influenced by interest and enjoyment, intellectual challenge and variety within the job. It is hoped that results will inform employers and those involved with training to enable them to better cater for the needs of the workforce and also encourage trainees to consider future family commitments when making career decisions. © 2012 The Authors. Internal Medicine Journal © 2012 Royal Australasian College of Physicians.

Factors influencing wood mobilization in Minnesota streams

USGS Publications Warehouse

Merten, Eric; Finlay, Jacques; Johnson, Lucinda; Newman, Raymond; Stefan, Heinz; Vondracek, Bruce C.

2010-01-01

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.

Factors influencing alcohol safety action project police officers' DWI arrests

DOT National Transportation Integrated Search

1974-04-29

This report summarizes the results of a study to determine the factors influencing ASAP police officers' DWI arrests and the formulation of approaches to minimize the influence of those factors which might tend to constrain the arrest of persons who ...

Relative Importance of Biotic and Abiotic Forces on the Composition and Dynamics of a Soft-Sediment Intertidal Community

PubMed Central

Barbeau, Myriam A.

2016-01-01

Top-down, bottom-up, middle-out and abiotic factors are usually viewed as main forces structuring biological communities, although assessment of their relative importance, in a single study, is rarely done. We quantified, using multivariate methods, associations between abiotic and biotic (top-down, bottom-up and middle-out) variables and infaunal population/community variation on intertidal mudflats in the Bay of Fundy, Canada, over two years. Our analysis indicated that spatial structural factors like site and plot accounted for most of the community and population variation. Although we observed a significant relationship between the community/populations and the biotic and abiotic variables, most were of minor importance relative to the structural factors. We suggest that community and population structure were relatively uncoupled from the structuring influences of biotic and abiotic factors in this system because of high concentrations of resources that sustain high densities of infauna and limit exploitative competition. Furthermore, we hypothesize that the infaunal community primarily reflects stochastic spatial events, namely a “first come, first served” process. PMID:26790098

Correlation between macrobenthic structure (biotic) and water-sediment characteristics (abiotic) adjacent aquaculture areas at Tembelas Island, indonesia

NASA Astrophysics Data System (ADS)

Sharani, Jeanny; Hidayat, Jafron W.; Putro, Sapto P.

2018-05-01

Macrobenthic community play important role in sedimentary habitats as a part of food chain. Their structure may be influenced by environmental characteristic spatially and temporally. The purpose of this study is to access the correlation between macrobenthic structure (biotic) and water-sediment characteristics (abiotic) adjacent aquaculture areas at Tembelas Island, Indonesia. Water and sediments samples were taken twice, where the first and second sampling time were taken in June and October 2016, respectively. Samples were taken in the area of fish farming at coastal area of policulture/IMTA (as Location I), site of 1 km away from fish farming area as a reference site (as Location II), and monoculture sites (as Location III), with three stations for each location. Data of abiotic parameters included the composition of sediment substrate and DO, pH, salinity, temperature, and. Sediment samples were taken using Ekman grab. The organisms were 1 mm -size sieved and fixed using 10% formalin for further analysis, i.e. sorting, preserving, enumerating, identifying, and grouping. The relationship between biotics (macrobentos) and abiotics (physical-chemical factors) was assessed using a non-parametric multivariate procedure (BIOENV). This study found 61 species consisting of 46 families and 5 classes of macrobenthos. The most common classes were member of Mollusca and Polychaeta. Total nitrogen, silt, and clay were the abiotic factors most influencing macrobenthic structure (BIO-ENV; r = 0.46; R2 = 21.16%).

[Bioavailability and factors influencing its rate].

PubMed

Vraníková, Barbora; Gajdziok, Jan

Bioavailability can be defined as the rate and range of active ingredient absorption, when it becomes available in the systemic circulation or at the desired site of drug action, respectively. Drug bioavailability after oral administration is affected by anumber of different factors, including physicochemical properties of the drug, physiological aspects, the type of dosage form, food intake, biorhythms, and intra- and interindividual variability of the human population. This article is the first from the series dealing with the bioavailability and methods leading to its improvement. The aim of the present paper is to provide an overview of aspects influencing the rate of bioavailability after oral administration of the active ingredient. Subsequentarticles will provide detailed descriptions of methods used for dug bioavailability improvement, which are here only summarized.

Factors influencing the measurement of closing volume.

PubMed

Make, B; Lapp, N L

1975-06-01

The various factors influencing closing volume were studied by performing the single-breath N2 test on 9 healthy nonsmokers. Time of day, day of the week, and preceding volume history had no effect on either closing volume or alveolar plateau. Slow inspiratory flow resulted in larger ratio of closing volume to vital capacity, ratio of closing capacity to total lung capacity, and change in N2 concentration than fast inspiratory flow. Voluntary regulation of the expiratory flow resulted in smaller ratios of closing volume to vital capacity and closing capacity to total lung capacity than when flow was regulated by a resistance. Prolonged breath holding of the inspired O2 led to larger ratio of closing volume to vital capacity and ratio of closing capacity to total lung capacity. To obtain uniform, comparable closing volumes, it is suggested that the subject inspire slowly, control expiratory flow (preferably voluntarily), and not pause between inspiration and expiration.

Factors influencing nurses' perceptions of occupational safety.

PubMed

Samur, Menevse; Intepeler, Seyda Seren

2017-01-02

To determine nurses' perceptions of occupational safety and their work environment and examine the sociodemographic traits and job characteristics that influence their occupational safety, we studied a sample of 278 nurses. According to the nurses, the quality of their work environment is average, and occupational safety is insufficient. In the subdimensions of the work environment scale, it was determined that the nurses think "labor force and other resources" are insufficient. In the occupational safety subdimensions "occupational illnesses and complaints" and "administrative support and approaches," they considered occupational safety to be insufficient. "Doctor-nurse-colleague relationships," "exposure to violence," and "work unit" (eg, internal medicine, surgical, intensive care) are the main factors that affect occupational safety. This study determined that hospital administrations should develop and immediately implement plans to ameliorate communication and clinical precautions and to reduce exposure to violence.

Factors influencing consumer dietary health preventative behaviours.

PubMed

Petrovici, Dan A; Ritson, Christopher

2006-09-01

The deterioration of the health status of the Romanian population during the economic transition from a centrally planned to a free market economy has been linked to lifestyles factors (e.g. diet) regarded as a main determinants of the disparity in life expectancy between Eastern and Western Europe. Reforms in the health care system in this transition economy aim to focus on preventive action. The purpose of this study was to identify the factors that impact on the individual decision to engage in Dietary Health Preventive Behaviour (DHPB) and investigate their influence in the context of an adapted health cognition model. A population-based study recruited 485 adult respondents using random route sampling and face-to-face administered questionnaires. Respondents' health motivation, beliefs that diet can prevent disease, knowledge about nutrition, level of education attainment and age have a positive influence on DHPB. Perceived barriers to healthy eating have a negative impact on alcohol moderation. The information acquisition behaviour (frequency of reading food labels) is negatively predicted by age and positively predicted by health motivation, education, self-reported knowledge about nutrition and household financial status. A significant segment of respondents believe they are not susceptible to the elicited diseases. Health promotion strategies should aim to change the judgments of health risk. The adaptation of the Health Belief Model and the Theory of Health Preventive Behaviour represents a valid framework of predicting DHPB. The negative sign of perceived threat of disease on DHPB may suggest that, under an income constraint, consumers tend to trade off long-term health benefits for short-term benefits. This cautions against the use of negative messages in public health campaigns. Raising the awareness of diet-disease relationships, knowledge about nutrition (particularly sources and risks associated with dietary fat and cholesterol) may induce people to

The copper complexation ability of a synthetic humic-like acid formed by an abiotic humification process and the effect of experimental factors on its copper complexation ability.

PubMed

Yang, Ting; Hodson, Mark E

2018-03-26

Humic acids have an important impact on the distribution, toxicity, and bioavailability of hazardous metals in the environment. In this study, a synthetic humic-like acid (SHLA) was prepared by an abiotic humification process using catechol and glycine as humic precursors and a MnO 2 catalyst. The effect of physico-chemical conditions (ionic strength from 0.01 to 0.5 M NaNO 3 , pH from 4 to 8, temperature from 25 to 45 °C, and humic acid concentration from 5 to 100 mg/L) on the complexation ability of SHLA for Cu 2+ were investigated. A commercial humic acid (CHA, CAS: 1415-93-6) from Sigma-Aldrich was also studied for comparison. The results showed that for pH 4 to 8, the conditional stability constants (log K) of SHLA and CHA were in the range 5.63-8.62 and 4.87-6.23, respectively, and complexation capacities (CC) were 1.34-2.61 and 1.42-2.31 mmol/g, respectively. The Cu complexation ability of SHLA was higher than that of the CHA due to its higher number of acidic functional groups (SHLA 19.19 mmol/g; CHA 3.87 mmol/g), extent of humification and aromaticity (AL/AR: 0.333 (SHLA); 1.554 (CHA)), and O-alkyl functional groups (SHLA 15.56%; CHA 3.45%). The log K and complexation efficiency (fraction of metal bound to SHLA) of SHLA were higher at higher pH, lower ionic strength, higher temperature, and higher SHLA concentration. Overall, SHLA was a good and promising complexation agent for copper in both soil washing of copper contaminated soil and the treatment of copper-containing wastewater.

Preoperative factors influencing success in pterygium surgery.

PubMed

Torres-Gimeno, Ana; Martínez-Costa, Lucía; Ayala, Guillermo

2012-08-08

To identify preoperative, perioperative and postoperative risk factors that influence the success of pterygium surgery. This is a prospective study of thirty-six patients with primary or recurrent pterygia. A detailed anamnesis and an ophthalmological examination were performed looking for the following factors: age, race, latitude and altitude of the main place of residence, hours of exposure to the sun, use of protective measures against UV-radiation, classification of pterygium, width of the pterygium at limbus, surgical technique (conjunctival autograft plus suturing versus tissue glue), graft alterations (misapposition, granuloma, haemorrhage, oedema, retraction or necrosis), and postoperative symptoms (foreign-body sensation, pain). The examinations were performed 2 and 7 days and 2, 6 and 12 months after surgery. In addition, recurrence was defined as any growth of conjunctiva into the cornea. A logistic regression and a survival analysis have been used to perform data analysis. A total number of 36 patients completed a one year follow-up. A total of 13 patients were born and lived in Spain, and 26 came from other countries, mostly Latin America. A total number of 8 males (no women) presented a recurrence, mainly between 2 and 6 months. The hours of sun exposure through their life was independently related to surgical success. Pterygia of less than 5 mm of base width showed a weak positive correlation with recurrence. None of the other factors considered were significantly related to recurrence. Male gender and high sun exposure are strongly and independently related to surgical success after the removal of pterygia.

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

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

Factors Influencing the Decline in Stroke Mortality

PubMed Central

Lackland, Daniel T.; Roccella, Edward J.; Deutsch, Anne; Fornage, Myriam; George, Mary G.; Howard, George; Kissela, Brett; Kittner, Steven J.; Lichtman, Judith H.; Lisabeth, Lynda; Schwamm, Lee H.; Smith, Eric E.; Towfighi, Amytis

2017-01-01

mortality results from reduced stroke incidence and lower case fatality rates. These significant improvements in stroke outcomes are concurrent with cardiovascular risk factor control interventions. While it is difficult to calculate specific attributable risk estimates, the hypertension control efforts initiated in the 1970s appears to have had the most substantial influence on the accelerated stroke mortality decline. Although implemented later in the time period, diabetes and dyslipidemia control and smoking cessation programs, particularly in combination with hypertension treatment, also appear to have contributed to the stroke mortality decline. Telemedicine and stroke systems of care, while showing strong potential effects, have not been in place long enough to show their influence on the decline. Other factors had probable effects, but additional studies are needed to determine their contributions. Conclusion The decline in stroke mortality is real and represents a major public health and clinical medicine success story. The repositioning of stroke from 3rd to 4th leading cause of death is the result of true mortality decline and not an increase of chronic lung disease mortality, which is now the 3rd leading cause of death in the United States. There is strong evidence the decline can be attributed to a combination of interventions and programs based on scientific findings and implemented with the purpose to reduce stroke risks, the most likely being improved hypertension control. Thus, research studies and the application of their findings to develop intervention programs have improved the health of the population. The continued application of aggressive evidence-based public health programs and clinical interventions are expected to result in further declines in stroke mortality. PMID:24309587

Soil moisture and biogeochemical factors influence the distribution of annual Bromus species

USGS Publications Warehouse

Belnap, Jayne; Stark, John Thomas; Rau, Benjamin; Allen, Edith B.; Phillips, Sue

2016-01-01

Abiotic factors have a strong influence on where annual Bromus species are found. At the large regional scale, temperature and precipitation extremes determine the boundaries of Bromusoccurrence. At the more local scale, soil characteristics and climate influence distribution, cover, and performance. In hot, dry, summer-rainfall-dominated deserts (Sonoran, Chihuahuan), little or noBromus is found, likely due to timing or amount of soil moisture relative to Bromus phenology. In hot, winter-rainfall-dominated deserts (parts of the Mojave Desert), Bromus rubens is widespread and correlated with high phosphorus availability. It also responds positively to additions of nitrogen alone or with phosphorus. On the Colorado Plateau, with higher soil moisture availability, factors limiting Bromus tectorum populations vary with life stage: phosphorus and water limit germination, potassium and the potassium/magnesium ratio affect winter performance, and water and potassium/magnesium affect spring performance. Controlling nutrients also change with elevation. In cooler deserts with winter precipitation (Great Basin, Columbia Plateau) and thus even greater soil moisture availability, B. tectorum populations are controlled by nitrogen, phosphorus, or potassium. Experimental nitrogen additions stimulate Bromus performance. The reason for different nutrients limiting in dissimilar climatic regions is not known, but it is likely that site conditions such as soil texture (as it affects water and nutrient availability), organic matter, and/or chemistry interact in a manner that regulates nutrient availability and limitations. Under future drier, hotter conditions,Bromus distribution is likely to change due to changes in the interaction between moisture and nutrient availability.

Maternal, social and abiotic environmental effects on growth vary across life stages in a cooperative mammal.

PubMed

English, Sinead; Bateman, Andrew W; Mares, Rafael; Ozgul, Arpat; Clutton-Brock, Tim H

2014-03-01

Resource availability plays a key role in driving variation in somatic growth and body condition, and the factors determining access to resources vary considerably across life stages. Parents and carers may exert important influences in early life, when individuals are nutritionally dependent, with abiotic environmental effects having stronger influences later in development as individuals forage independently. Most studies have measured specific factors influencing growth across development or have compared relative influences of different factors within specific life stages. Such studies may not capture whether early-life factors continue to have delayed effects at later stages, or whether social factors change when individuals become nutritionally independent and adults become competitors for, rather than providers of, food. Here, we examined variation in the influence of the abiotic, social and maternal environment on growth across life stages in a wild population of cooperatively breeding meerkats. Cooperatively breeding vertebrates are ideal for investigating environmental influences on growth. In addition to experiencing highly variable abiotic conditions, cooperative breeders are typified by heterogeneity both among breeders, with mothers varying in age and social status, and in the number of carers present. Recent rainfall had a consistently marked effect on growth across life stages, yet other seasonal terms only influenced growth during stages when individuals were growing fastest. Group size and maternal dominance status had positive effects on growth during the period of nutritional dependence on carers, but did not influence mass at emergence (at 1 month) or growth at independent stages (>4 months). Pups born to older mothers were lighter at 1 month of age and subsequently grew faster as subadults. Males grew faster than females during the juvenile and subadult stage only. Our findings demonstrate the complex ways in which the external environment

Maternal, social and abiotic environmental effects on growth vary across life stages in a cooperative mammal

PubMed Central

English, Sinead; Bateman, Andrew W; Mares, Rafael; Ozgul, Arpat; Clutton-Brock, Tim H

2014-01-01

Resource availability plays a key role in driving variation in somatic growth and body condition, and the factors determining access to resources vary considerably across life stages. Parents and carers may exert important influences in early life, when individuals are nutritionally dependent, with abiotic environmental effects having stronger influences later in development as individuals forage independently. Most studies have measured specific factors influencing growth across development or have compared relative influences of different factors within specific life stages. Such studies may not capture whether early-life factors continue to have delayed effects at later stages, or whether social factors change when individuals become nutritionally independent and adults become competitors for, rather than providers of, food. Here, we examined variation in the influence of the abiotic, social and maternal environment on growth across life stages in a wild population of cooperatively breeding meerkats. Cooperatively breeding vertebrates are ideal for investigating environmental influences on growth. In addition to experiencing highly variable abiotic conditions, cooperative breeders are typified by heterogeneity both among breeders, with mothers varying in age and social status, and in the number of carers present. Recent rainfall had a consistently marked effect on growth across life stages, yet other seasonal terms only influenced growth during stages when individuals were growing fastest. Group size and maternal dominance status had positive effects on growth during the period of nutritional dependence on carers, but did not influence mass at emergence (at 1 month) or growth at independent stages (>4 months). Pups born to older mothers were lighter at 1 month of age and subsequently grew faster as subadults. Males grew faster than females during the juvenile and subadult stage only. Our findings demonstrate the complex ways in which the external environment

[Agglutination and phagocytosis of foreign abiotic particles by bluebottle Calliphora vicina haemocytes in vivo. II. Influence of the previous septic immune induction on haemocytic activity].

PubMed

Kind, T V

2010-01-01

The rate of Calliphora vicina haemocytic defense reaction to foreign particles injection depends on the larval age and on the previous bacterial immunization. Immunization of crop-empting larvae induces an evident increase in particles phagocytosis by juvenile plasmatocytes in 24 h after injection. Both the hemogram and the pattern of cellular defense reaction change significantly after crop-empting. Immunized larvae start intensive adhesion of foreign particles to plasmatocytes surface and formation of great aggregations of plasmatocytes (morules) no longer than in 34 min after injection. The period of particle-haemocyte adhesion is short-termed and no more than after 30 min cell aggregates dissociate and adhered charcoal particles pass to thrombocydoidal agglutinates. Unimmunized control larvae of the same age have shown no adhesion and morules formation. In immunized wadering and diapausing larvae, formation of capsules consisting of central thrombocydoidal agglutinate filled with alien particles and adherent plasmatocytes I is intensified. In contrast to moru-les, this capsule formation is not accompanied by charcoal particles adhesion to plasmatocytes. Immunization of mature larvae of C. vicina shown no prominent influence on both the rate of phagocytosis and the hyaline cells differentiation. It might be supposed that the receptors system is complex and the immunization both the mechanisms of foreigners recognition (adhesion, morulation and incapsulation) and the far more lately occurring phagocytosis.

Abscisic Acid and abiotic stress signaling.

PubMed

Tuteja, Narendra

2007-05-01

Abiotic stress is severe environmental stress, which impairs crop production on irrigated land worldwide. Overall, the susceptibility or tolerance to the stress in plants is a coordinated action of multiple stress responsive genes, which also cross-talk with other components of stress signal transduction pathways. Plant responses to abiotic stress can be determined by the severity of the stress and by the metabolic status of the plant. Abscisic acid (ABA) is a phytohormone critical for plant growth and development and plays an important role in integrating various stress signals and controlling downstream stress responses. Plants have to adjust ABA levels constantly in responce to changing physiological and environmental conditions. To date, the mechanisms for fine-tuning of ABA levels remain elusive. The mechanisms by which plants respond to stress include both ABA-dependent and ABA-independent processes. Various transcription factors such as DREB2A/2B, AREB1, RD22BP1 and MYC/MYB are known to regulate the ABA-responsive gene expression through interacting with their corrosponding cis-acting elements such as DRE/CRT, ABRE and MYCRS/MYBRS, respectively. Understanding these mechanisms is important to improve stress tolerance in crops plants. This article first describes the general pathway for plant stress response followed by roles of ABA and transcription factors in stress tolerance including the regulation of ABA biosynthesis.

Abscisic Acid and Abiotic Stress Signaling

PubMed Central

2007-01-01

Abiotic stress is severe environmental stress, which impairs crop production on irrigated land worldwide. Overall, the susceptibility or tolerance to the stress in plants is a coordinated action of multiple stress responsive genes, which also cross-talk with other components of stress signal transduction pathways. Plant responses to abiotic stress can be determined by the severity of the stress and by the metabolic status of the plant. Abscisic acid (ABA) is a phytohormone critical for plant growth and development and plays an important role in integrating various stress signals and controlling downstream stress responses. Plants have to adjust ABA levels constantly in responce to changing physiological and environmental conditions. To date, the mechanisms for fine-tuning of ABA levels remain elusive. The mechanisms by which plants respond to stress include both ABA-dependent and ABA-independent processes. Various transcription factors such as DREB2A/2B, AREB1, RD22BP1 and MYC/MYB are known to regulate the ABA-responsive gene expression through interacting with their corrosponding cis-acting elements such as DRE/CRT, ABRE and MYCRS/MYBRS, respectively. Understanding these mechanisms is important to improve stress tolerance in crops plants. This article first describes the general pathway for plant stress response followed by roles of ABA and transcription factors in stress tolerance including the regulation of ABA biosynthesis. PMID:19516981

Factors influencing arrests for alcohol-related traffic violations

DOT National Transportation Integrated Search

1974-09-01

This report describes factors that were found to influence police officers' arrests of persons suspected of alcohol-related (A/R) traffic violations, and presents recommendations for treating these factors so that a higher level of enforcement might ...

Factors influencing organic-horizon carbon pools in mixed-species stands of central Maine, USA

Treesearch

Joshua J. Puhlick; Shawn Fraver; Ivan J. Fernandez; Aaron R. Weiskittel; Laura S. Kenefic; Randy Kolka; Marie-Cecile Gruselle

2016-01-01

The overall goal of this study was to evaluate the correlation of multiple abiotic and biotic factors with organic-horizon (O-horizon) carbon (C) content on the Penobscot Experimental Forest in central Maine, USA. O-horizon samples were collected and their associated depths were recorded from stands managed with a range of silvicultural and harvesting treatments (i.e...

Widespread abiotic methane in chromitites.

PubMed

Etiope, G; Ifandi, E; Nazzari, M; Procesi, M; Tsikouras, B; Ventura, G; Steele, A; Tardini, R; Szatmari, P

2018-06-07

Recurring discoveries of abiotic methane in gas seeps and springs in ophiolites and peridotite massifs worldwide raised the question of where, in which rocks, methane was generated. Answers will impact the theories on life origin related to serpentinization of ultramafic rocks, and the origin of methane on rocky planets. Here we document, through molecular and isotopic analyses of gas liberated by rock crushing, that among the several mafic and ultramafic rocks composing classic ophiolites in Greece, i.e., serpentinite, peridotite, chromitite, gabbro, rodingite and basalt, only chromitites, characterized by high concentrations of chromium and ruthenium, host considerable amounts of 13 C-enriched methane, hydrogen and heavier hydrocarbons with inverse isotopic trend, which is typical of abiotic gas origin. Raman analyses are consistent with methane being occluded in widespread microfractures and porous serpentine- or chlorite-filled veins. Chromium and ruthenium may be key metal catalysts for methane production via Sabatier reaction. Chromitites may represent source rocks of abiotic methane on Earth and, potentially, on Mars.

MICROSCALE METABOLIC, REDOX AND ABIOTIC REACTIONS IN HANFORD 300 AREA SUBSURFACE SEDIMENTS

SciTech Connect

Beyenal, Haluk; McLEan, Jeff; Majors, Paul

2013-11-14

The Hanford 300 Area is a unique site due to periodic hydrologic influence of river water resulting in changes in groundwater elevation and flow direction. This area is also highly subject to uranium remobilization, the source of which is currently believed to be the region at the base of the vadose zone that is subject to period saturation due to the changes in the water levels in the Columbia River. We found that microbial processes and redox and abiotic reactions which operate at the microscale were critical to understanding factors controlling the macroscopic fate and transport of contaminants in themore » subsurface. The combined laboratory and field research showed how microscale conditions control uranium mobility and how biotic, abiotic and redox reactions relate to each other. Our findings extended the current knowledge to examine U(VI) reduction and immobilization using natural 300 Area communities as well as selected model organisms on redox-sensitive and redox-insensitive minerals. Using innovative techniques developed specifically to probe biogeochemical processes at the microscale, our research expanded our current understanding of the roles played by mineral surfaces, bacterial competition, and local biotic, abiotic and redox reaction rates on the reduction and immobilization of uranium.« less

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…

Factors Influencing Career Aspirations of Primary and Secondary Grade Students.

ERIC Educational Resources Information Center

Canale, Joseph R.; Dunlap, Linda L.

Many studies have examined factors influencing the career aspirations of high school students, but little has been done to explore this issue with primary school students. This study investigated factors that might influence the career aspirations of children across a broad age spectrum. Students (N=150) from grades 2, 5, 8, and 12 completed…

Factors influencing selection of office furniture by corporations and universities

Treesearch

R. Bruce Anderson

1976-01-01

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

Marketing Factors Influencing the Overall Satisfaction of Marriage Education Participants.

ERIC Educational Resources Information Center

Morris, Michael Lane; Cooper, Catherine; Gross, Kevin H.

1999-01-01

Seventy-one married couples attending marriage education workshops were surveyed regarding price, product, place, people, and promotional marketing factors influencing their overall satisfaction as workshop participants. Findings suggest both similar and unique marketing factors influenced husbands' and wives' satisfaction. Recommendations for…

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…

Factors Influencing Student Achievement in Reading

ERIC Educational Resources Information Center

Dawkins, Lakeshia Darby

2017-01-01

The purpose of this study was to understand the reasons, as perceived by elementary school teachers at the target Title I school, for low student achievement in reading. The conceptual framework that guided this study was the ecological theory that postulates that students' academic achievement is influenced by several subsystems that affect human…

Auditory fatigue : influence of mental factors.

DOT National Transportation Integrated Search

1965-01-01

Conflicting reports regarding the influence of mental tasks on auditory fatigue have recently appeared in the literature. In the present study, 10 male subjects were exposed to 4000 cps fatigue toe at 40 dB SL for 3 min under conditions of mental ari...

Environmental factors influencing the risk of autism

PubMed Central

Karimi, Padideh; Kamali, Elahe; Mousavi, Seyyed Mohammad; Karahmadi, Mojgan

2017-01-01

Autism is a developmental disability with age of onset in childhood (under 3 years old), which is characterized by definite impairments in social interactions, abnormalities in speech, and stereotyped pattern of behaviors. Due to the progress of autism in recent decades, a wide range of studies have been done to identify the etiological factors of autism. It has been found that genetic and environmental factors are both involved in autism pathogenesis. Hence, in this review article, a set of environmental factors involved in the occurrence of autism has been collected, and finally, some practical recommendations for reduction of the risk of this devastating disease in children are represented. PMID:28413424

Root Systems of Individual Plants, and the Biotic and Abiotic Factors Controlling Their Depth and Distribution: a Synthesis Using a Global Database.

NASA Astrophysics Data System (ADS)

Tumber-Davila, S. J.; Schenk, H. J.; Jackson, R. B.

2017-12-01

This synthesis examines plant rooting distributions globally, by doubling the number of entries in the Root Systems of Individual Plants database (RSIP) created by Schenk and Jackson. Root systems influence many processes, including water and nutrient uptake and soil carbon storage. Root systems also mediate vegetation responses to changing climatic and environmental conditions. Therefore, a collective understanding of the importance of rooting systems to carbon sequestration, soil characteristics, hydrology, and climate, is needed. Current global models are limited by a poor understanding of the mechanisms affecting rooting, carbon stocks, and belowground biomass. This improved database contains an extensive bank of records describing the rooting system of individual plants, as well as detailed information on the climate and environment from which the observations are made. The expanded RSIP database will: 1) increase our understanding of rooting depths, lateral root spreads and above and belowground allometry; 2) improve the representation of plant rooting systems in Earth System Models; 3) enable studies of how climate change will alter and interact with plant species and functional groups in the future. We further focus on how plant rooting behavior responds to variations in climate and the environment, and create a model that can predict rooting behavior given a set of environmental conditions. Preliminary results suggest that high potential evapotranspiration and seasonality of precipitation are indicative of deeper rooting after accounting for plant growth form. When mapping predicted deep rooting by climate, we predict deepest rooting to occur in equatorial South America, Africa, and central India.

Abiotic stress responses in plants: roles of calmodulin-regulated proteins.

PubMed

Virdi, Amardeep S; Singh, Supreet; Singh, Prabhjeet

2015-01-01

Intracellular changes in calcium ions (Ca(2+)) in response to different biotic and abiotic stimuli are detected by various sensor proteins in the plant cell. Calmodulin (CaM) is one of the most extensively studied Ca(2+)-sensing proteins and has been shown to be involved in transduction of Ca(2+) signals. After interacting with Ca(2+), CaM undergoes conformational change and influences the activities of a diverse range of CaM-binding proteins. A number of CaM-binding proteins have also been implicated in stress responses in plants, highlighting the central role played by CaM in adaptation to adverse environmental conditions. Stress adaptation in plants is a highly complex and multigenic response. Identification and characterization of CaM-modulated proteins in relation to different abiotic stresses could, therefore, prove to be essential for a deeper understanding of the molecular mechanisms involved in abiotic stress tolerance in plants. Various studies have revealed involvement of CaM in regulation of metal ions uptake, generation of reactive oxygen species and modulation of transcription factors such as CAMTA3, GTL1, and WRKY39. Activities of several kinases and phosphatases have also been shown to be modulated by CaM, thus providing further versatility to stress-associated signal transduction pathways. The results obtained from contemporary studies are consistent with the proposed role of CaM as an integrator of different stress signaling pathways, which allows plants to maintain homeostasis between different cellular processes. In this review, we have attempted to present the current state of understanding of the role of CaM in modulating different stress-regulated proteins and its implications in augmenting abiotic stress tolerance in plants.

Abiotic stress responses in plants: roles of calmodulin-regulated proteins

PubMed Central

Virdi, Amardeep S.; Singh, Supreet; Singh, Prabhjeet

2015-01-01

Intracellular changes in calcium ions (Ca2+) in response to different biotic and abiotic stimuli are detected by various sensor proteins in the plant cell. Calmodulin (CaM) is one of the most extensively studied Ca2+-sensing proteins and has been shown to be involved in transduction of Ca2+ signals. After interacting with Ca2+, CaM undergoes conformational change and influences the activities of a diverse range of CaM-binding proteins. A number of CaM-binding proteins have also been implicated in stress responses in plants, highlighting the central role played by CaM in adaptation to adverse environmental conditions. Stress adaptation in plants is a highly complex and multigenic response. Identification and characterization of CaM-modulated proteins in relation to different abiotic stresses could, therefore, prove to be essential for a deeper understanding of the molecular mechanisms involved in abiotic stress tolerance in plants. Various studies have revealed involvement of CaM in regulation of metal ions uptake, generation of reactive oxygen species and modulation of transcription factors such as CAMTA3, GTL1, and WRKY39. Activities of several kinases and phosphatases have also been shown to be modulated by CaM, thus providing further versatility to stress-associated signal transduction pathways. The results obtained from contemporary studies are consistent with the proposed role of CaM as an integrator of different stress signaling pathways, which allows plants to maintain homeostasis between different cellular processes. In this review, we have attempted to present the current state of understanding of the role of CaM in modulating different stress-regulated proteins and its implications in augmenting abiotic stress tolerance in plants. PMID:26528296

Influence of Environmental Factors on the Production of Penitrems A-F by Penicillium crustosum.

PubMed

Kalinina, Svetlana A; Jagels, Annika; Cramer, Benedikt; Geisen, Rolf; Humpf, Hans-Ulrich

2017-07-01

Filamentous fungi produce a multitude of secondary metabolites, some of them known as mycotoxins, which are toxic to vertebrates and other animal groups in low concentrations. Among them, penitrems, which belong to the group of indole-diterpene mycotoxins, are synthesized by Penicillium and Aspergillus genera and exhibit potent tremorgenic effects. This is the first complex study of the penitrems A-F production under the influence of different abiotic factors, e.g., media, incubation time, temperature, pH, light, water activity, and carbon and nitrogen source as well as oxidative and salt stress. For this purpose, penitrems A-F were isolated from Penicillium crustosum cultures and used as analytical standards. Among the carbon sources, glucose supplemented to the media at the concentration of 50 g/L, showed the strongest inducing effect on the biosynthesis of penitrems. Among nitrogen sources, glutamate was found to be the most favorable supplement, significantly increasing production of these secondary metabolites. CuSO4-promoted oxidative stress was also shown to remarkably stimulate biosynthesis of all penitrems. In contrast, the salt stress, caused by the elevated concentrations of NaCl, showed an inhibitory effect on the penitrem biosynthesis. Finally, cheese model medium elicited exceptionally high production of all members of the penitrems family. Obtained results give insides into the biosynthesis of toxicologically relevant penitrems A-F under different environmental factors and can be utilized to prevent food contamination.

Factors that influence the beta-diversity of spider communities in northwestern Argentinean Grasslands

PubMed Central

Rodriguez-Artigas, Sandra M.; Ballester, Rodrigo

2016-01-01

Beta-diversity, defined as spatial replacement in species composition, is crucial to the understanding of how local communities assemble. These changes can be driven by environmental or geographic factors (such as geographic distance), or a combination of the two. Spiders have been shown to be good indicators of environmental quality. Accordingly, spiders are used in this work as model taxa to establish whether there is a decrease in community similarity that corresponds to geographic distance in the grasslands of the Campos & Malezales ecoregion (Corrientes). Furthermore, the influence of climactic factors and local vegetation heterogeneity (environmental factors) on assemblage composition was evaluated. Finally, this study evaluated whether the differential dispersal capacity of spider families is a factor that influences their community structure at a regional scale. Spiders were collected with a G-Vac from vegetation in six grassland sites in the Campos & Malezales ecoregion that were separated by a minimum of 13 km. With this data, the impact of alpha-diversity and different environmental variables on the beta-diversity of spider communities was analysed. Likewise, the importance of species replacement and nesting on beta-diversity and their contribution to the regional diversity of spider families with different dispersion capacities was evaluated. The regional and site-specific inventories obtained were complete. The similarity between spider communities declined as the geographic distance between sites increased. Environmental variables also influenced community composition; stochastic events and abiotic forces were the principal intervening factors in assembly structure. The differential dispersal capacity of spider groups also influenced community structure at a regional scale. The regional beta-diversity, as well as species replacement, was greater in high and intermediate vagility spiders; while nesting was greater in spiders with low dispersion

Proteins in phytohormone signaling pathways for abiotic stress in plants

USDA-ARS?s Scientific Manuscript database

Plant hormones and their signaling network systems have an essential role in activating and regulating plant responses to both biotic and abiotic stress factors. This chapter describes proteins that are involved in hormone biosynthesis, long distance and intra-cellular transport, the signaling sensi...

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…

Factors influencing large wildland fire suppression expenditures

Treesearch

Jingjing Liang; Dave E. Calkin; Krista M. Gebert; Tyron J. Venn; Robin P. Silverstein

2008-01-01

There is an urgent and immediate need to address the excessive cost of large fires. Here, we studied large wildland fire suppression expenditures by the US Department of Agriculture Forest Service. Among 16 potential nonmanagerial factors, which represented fire size and shape, private properties, public land attributes, forest and fuel conditions, and geographic...

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…

Factors Influencing Young People's Conceptions of Environment.

ERIC Educational Resources Information Center

Loughland, Tony; Reid, Anna; Walker, Kim; Petocz, Peter

2003-01-01

Explains the importance of environmental education in schools for achieving environmental protection and improvement. Statistically examines factors that incline students to a 'relation' rather than an 'object' conception of the environment. Concludes that development of the former would seem to be an important aim of environmental education and…

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…

Spatial distribution of soil organic carbon and its influencing factors in desert grasslands of the Hexi Corridor, northwest China.

PubMed

Wang, Min; Su, Yongzhong; Yang, Xiao

2014-01-01

Knowledge of the distribution patterns of soil organic carbon (SOC) and factors that influence these patterns is crucial for understanding the carbon cycle. The objectives of this study were to determine the spatial distribution pattern of soil organic carbon density (SOCD) and the controlling factors in arid desert grasslands of northwest China. The above- and belowground biomass and SOCD in 260 soil profiles from 52 sites over 2.7×10(4) km2 were investigated. Combined with a satellite-based dataset of an enhanced vegetation index during 2011-2012 and climatic factors at different sites, the relationships between SOCD and biotic and abiotic factors were identified. The results indicated that the mean SOCD was 1.20 (SD:+/- 0.85), 1.73 (SD:+/- 1.20), and 2.69 (SD:+/- 1.91) kg m(-2) at soil depths of 0-30 cm, 0-50 cm, and 0-100 cm, respectively, which was smaller than other estimates in temperate grassland, steppe, and desert-grassland ecosystems. The spatial distribution of SOCD gradually decreased from the southeast to the northwest, corresponding to the precipitation gradient. SOCD increased significantly with vegetation biomass, annual precipitation, soil moisture, clay and silt content, and decreased with mean annual temperature and sand content. The correlation between BGB and SOCD was closer than the correlation between AGB and SOCD. Variables could together explain about 69.8%, 74.4%, and 78.9% of total variation in SOCD at 0-30 cm, 0-50 cm, and 0-100 cm, respectively. In addition, we found that mean annual temperature is more important than other abiotic factors in determining SOCD in arid desert grasslands in our study area. The information obtained in this study provides a basis for accurately estimating SOC stocks and assessing carbon (C) sequestration potential in the desert grasslands of northwest China.

Factors influencing career success in nursing.

PubMed

Zimmerman, L; Yeaworth, R

1986-06-01

The purpose of this descriptive study was to examine educational preparation, personal characteristics, and significant others in the career success of women in nursing. The sample was a random selection of 194 doctorally prepared female nurses who reported some degree of career success. The factor, personal characteristics, was ranked as the most important in facilitating career success, educational preparations was ranked second, and significant others was ranked third. Among significant others ranked as influential were teachers, peer/colleagues, and supervisors.

Factors influencing specific fuel use in Nebraska

SciTech Connect

Shelton, D.P.; Von Bargen, K.

1981-01-01

Fuel use data relating to agricultural field operations were collected and analyzed during the Nebraska fuel use survey. The farms surveyed had a mean size of 598 ha and a mean total tractor power rating of 221 kW. Mean operating depth, field speed, and tractor power rating were determined for the major field operations. Mean field speeds were generally in agreement with commonly accepted values. Total annual fuel energy use increased with increasing farm size. Over 87 percent of this energy was used from April through October. Even though total fuel energy was increased, specific fuel energy use decreased withmore » increasing farm size. Specific fuel use for field operations was influenced by the size of area worked, operation depth, field speed, and tractor power rating.« less

Mud, Macrofauna and Microbes: An ode to benthic organism-abiotic interactions at varying scales

EPA Science Inventory

Benthic environments are dynamic habitats, subject to variable sources and rates of sediment delivery, reworking from the abiotic and biotic processes, and complex biogeochemistry. These activities do not occur in a vacuum, and interact synergistically to influence food webs, bi...

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

PubMed

Rojatz, Daniela; Merchant, Almas; Nitsch, Martina

2017-10-01

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

Role of Biotic and Abiotic Processes on Soil CO2 Dynamics in the McMurdo Dry Valleys, Antarctica

NASA Astrophysics Data System (ADS)

Risk, D. A.; Macintyre, C. M.; Lee, C.; Cary, C.; Shanhun, F.; Almond, P. C.

2016-12-01

In the harsh conditions of the Antarctic Dry Valleys, microbial activity has been recorded via measurements of soil carbon dioxide (CO2) concentration and surface efflux. However, high temporal resolution studies in the Dry Valleys have also shown that abiotic solubility-driven processes can strongly influence (and perhaps even dominate) the CO2 dynamics in these low flux environments and suggests that biological activity may be lower than previously thought. In this study, we aim to improve our understanding of CO2 dynamics (biotic and abiotic) in Antarctic Dry Valley soils using long-term automated measurements of soil CO2 surface flux and soil profile concentration at several sites, often at sub-diel frequency. We hypothesize that soil CO2 variations are driven primarily by environmental factors affecting CO2 solubility in soil solution, mainly temperature, and that these processes may even overprint biologic production in representative Dry Valley soils. Monitoring of all sites revealed only one likely biotic CO2 production event, lasting three weeks during the Austral summer and reaching fluxes of 0.4 µmol/m2/s. Under more typical low flux conditions (<0.10 µmol/m2/s) we observed a cyclical daily sink/source pattern consistent with CO2 solubility cycling that would not generally have been evident with normal synoptic afternoon sampling campaigns. Subsurface CO2 monitoring and a lab-controlled Antarctic soil simulation experiment confirmed that abiotic processes are capable of dominating soil CO2 variability. Diel temperature cycles crossing the freezing boundary revealed a dual abiotic cycle of solubility cycling and gas exclusion from ice formation observed only by high temporal frequency measurements (30 min). This work demonstrates a need for a numerical model to partition the dynamic abiotic processes underlying any biotic CO2 production in order to understand potential climate-change induced increases in microbial productivity in terrestrial Antarctica.

Factors influencing microinjection molding replication quality

NASA Astrophysics Data System (ADS)

Vera, Julie; Brulez, Anne-Catherine; Contraires, Elise; Larochette, Mathieu; Trannoy-Orban, Nathalie; Pignon, Maxime; Mauclair, Cyril; Valette, Stéphane; Benayoun, Stéphane

2018-01-01

In recent years, there has been increased interest in producing and providing high-precision plastic parts that can be manufactured by microinjection molding: gears, pumps, optical grating elements, and so on. For all of these applications, the replication quality is essential. This study has two goals: (1) fabrication of high-precision parts using the conventional injection molding machine; (2) identification of robust parameters that ensure production quality. Thus, different technological solutions have been used: cavity vacuuming and the use of a mold coated with DLC or CrN deposits. AFM and SEM analyses were carried out to characterize the replication profile. The replication quality was studied in terms of the process parameters, coated and uncoated molds and crystallinity of the polymer. Specific studies were processed to quantify the replicability of injection molded parts (ABS, PC and PP). Analysis of the Taguchi experimental designs permits prioritization of the impact of each parameter on the replication quality. A discussion taking into account these new parameters and the thermal and spreading properties on the coatings is proposed. It appeared that, in general, increasing the mold temperature improves the molten polymer fill in submicron features except for the steel insert (for which the presence of a vacuum is the most important factor). Moreover, the DLC coating was the best coating to increase the quality of the replication. This result could be explained by the lower thermal diffusivity of this coating. We noted that the viscosity of the polymers is not a primordial factor of the replication quality.

Socioeconomic factors influencing cosmetic usage patterns.

PubMed

Park, Gyeong-Hun; Nam, Chanhee; Hong, Seungphil; Park, Byungcheol; Kim, Hakrim; Lee, Taewon; Kim, Kyubong; Lee, Jong Hee; Kim, Myung Hwa

2018-05-01

Despite daily exposure to chemicals in cosmetic products, there are few studies on the exposure levels to cosmetics particularly in Asians. We sought to investigate the usage pattern of cosmetics, including eye makeup products, fragrances, color makeups, and hair and nail care products, in Koreans. An online survey of 1,800 participants (908 males and 892 females, aged 15-59 years) from 5 Metropolitan cities (Seoul, Incheon, Daejeon, Daegu, and Busan) in Korea was conducted. For overall types of cosmetics, the proportion of users was 7.1% (range: 0.0-46.3%) in males and 30.7% (range: 1.0-82.8%) in females. The most prevalently used product was perfume (46.3%) in males and lipstick (82.8%) in females. In addition, the mean number of application for overall types of cosmetics was 22.7 (range: 4.6-49.4) times per month in male users and 24.8 (range: 4.2-62.0) in female users. The usage pattern was significantly altered according to demographic and socioeconomic factors, including age group, occupation, and income. This work estimated the prevalences and frequencies of use of a wide collection of cosmetics from a large number of Koreans and found that the usage pattern was significantly associated with demographic and socioeconomic factors.

Factors influencing consumer satisfaction with health care.

PubMed

Deshpande, Satish P; Deshpande, Samir S

2014-01-01

The purpose of this study was to examine factors that impact consumer satisfaction with health care. This is a secondary analysis of the Center for Studying Health System Change's 2010 Health Tracking Household Survey. Regression analysis was used to examine the impact of treatment issues, financial issues, family-related issues, sources of health care information, location, and demographics-related factors on satisfaction with health care. The study involved 12280 subjects, 56% of whom were very satisfied with their health care, whereas 66% were very satisfied with their primary care physician. Fourteen percent of the subjects had no health insurance; 34% of the subjects got their health care information from the Web. Satisfaction with primary care physician, general health status, promptness of visit to doctor, insurance type, medical cost per family, annual income, persons in family, health care information from friends, and age significantly impacted satisfaction with health care. The regression models accounted for 23% of the variance in health care satisfaction. Satisfaction with primary care physicians, health insurance, and general health status are the 3 most significant indicators of an individual's satisfaction with health care.

Factors that influence current tuberculosis epidemiology.

PubMed

Millet, Juan-Pablo; Moreno, Antonio; Fina, Laia; del Baño, Lucía; Orcau, Angels; de Olalla, Patricia García; Caylà, Joan A

2013-06-01

According to WHO estimates, in 2010 there were 8.8 million new cases of tuberculosis (TB) and 1.5 million deaths. TB has been classically associated with poverty, overcrowding and malnutrition. Low income countries and deprived areas, within big cities in developed countries, present the highest TB incidences and TB mortality rates. These are the settings where immigration, important social inequalities, HIV infection and drug or alcohol abuse may coexist, all factors strongly associated with TB. In spite of the political, economical, research and community efforts, TB remains a major global health problem worldwide. Moreover, in this new century, new challenges such as multidrug-resistance extension, migration to big cities and the new treatments with anti-tumour necrosis alpha factor for inflammatory diseases have emerged and threaten the decreasing trend in the global number of TB cases in the last years. We must also be aware about the impact that smoking and diabetes pandemics may be having on the incidence of TB. The existence of a good TB Prevention and Control Program is essential to fight against TB. The coordination among clinicians, microbiologists, epidemiologists and others, and the link between surveillance, control and research should always be a priority for a TB Program. Each city and country should define their needs according to the epidemiological situation. Local TB control programs will have to adapt to any new challenge that arises in order to respond to the needs of their population.

Factors influencing antibiotics adsorption onto engineered adsorbents.

PubMed

Xia, Mingfang; Li, Aimin; Zhu, Zhaolian; Zhou, Qin; Yang, Weiben

2013-07-01

The study evaluated the adsorption of two antibiotics by four engineered adsorbents (hypercrosslinked resin MN-202, macroporous resin XAD-4, activated carbon F-400, and multi-walled carbon nanotubes (MWCNT)) from aqueous solutions. The dynamic results demonstrated the dominant influence of pore size in adsorption. The adsorption amounts of antibiotics on XAD-4 were attributed to the hydrophobic effect, whereas steric hindrance or micropore-filling played a main role in the adsorption of antibiotics by F-400 because of its high microporosity. Aside from F-400, similar patterns of pH-dependent adsorption were observed, implying the importance of antibiotic molecular forms to the adsorption process for adsorbents. Increasing the ionic concentration with CaC12 produced particular adsorption characteristics on MWCNT at pH 2.0 and F-400 at pH 8.0, which were attributed to the highly available contact surfaces and molecular sieving, respectively. Its hybrid characteristics incorporating a considerable portion of mesopores and micropores made hypercross linked MN-202 a superior antibiotic adsorbent with high adsorption capacity. Furthermore, the adsorption capacity of MWCNT on the basis of surface area was more advantageous than that of the other adsorbents because MWCNT has a much more compact molecular arrangement.

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.

Linguistic Factors Influencing Speech Audiometric Assessment

PubMed Central

Krijger, Stefanie; Meeuws, Matthias; De Ceulaer, Geert

2016-01-01

In speech audiometric testing, hearing performance is typically measured by calculating the number of correct repetitions of a speech stimulus. We investigate to what extent the repetition accuracy of Dutch speech stimuli presented against a background noise is influenced by nonauditory processes. We show that variation in verbal repetition accuracy is partially explained by morpholexical and syntactic features of the target language. Verbs, prepositions, conjunctions, determiners, and pronouns yield significantly lower correct repetitions than nouns, adjectives, or adverbs. The reduced repetition performance for verbs and function words is probably best explained by the similarities in the perceptual nature of verbal morphology and function words in Dutch. For sentences, an overall negative effect of syntactic complexity on speech repetition accuracy was found. The lowest number of correct repetitions was obtained with passive sentences, reflecting the cognitive cost of processing a noncanonical sentence structure. Taken together, these findings may have important implications for the audiological practice. In combination with hearing loss, linguistic complexity may increase the cognitive demands to process sentences in noise, leading to suboptimal functional hearing in day-to-day listening situations. Using test sentences with varying degrees of syntactic complexity may therefore provide useful information to measure functional hearing benefits. PMID:27830152

Alternative Splicing Control of Abiotic Stress Responses.

PubMed

Laloum, Tom; Martín, Guiomar; Duque, Paula

2018-02-01

Alternative splicing, which generates multiple transcripts from the same gene, is an important modulator of gene expression that can increase proteome diversity and regulate mRNA levels. In plants, this post-transcriptional mechanism is markedly induced in response to environmental stress, and recent studies have identified alternative splicing events that allow rapid adjustment of the abundance and function of key stress-response components. In agreement, plant mutants defective in splicing factors are severely impaired in their response to abiotic stress. Notably, mounting evidence indicates that alternative splicing regulates stress responses largely by targeting the abscisic acid (ABA) pathway. We review here current understanding of post-transcriptional control of plant stress tolerance via alternative splicing and discuss research challenges for the near future. Copyright © 2017 Elsevier Ltd. All rights reserved.

Factors influencing message dissemination through social media

NASA Astrophysics Data System (ADS)

Zheng, Zeyu; Yang, Huancheng; Fu, Yang; Fu, Dianzheng; Podobnik, Boris; Stanley, H. Eugene

2018-06-01

Online social networks strongly impact our daily lives. An internet user (a "Netizen") wants messages to be efficiently disseminated. The susceptible-infected-recovered (SIR) dissemination model is the traditional tool for exploring the spreading mechanism of information diffusion. We here test our SIR-based dissemination model on open and real-world data collected from Twitter. We locate and identify phase transitions in the message dissemination process. We find that message content is a stronger factor than the popularity of the sender. We also find that the probability that a message will be forwarded has a threshold that affects its ability to spread, and when the probability is above the threshold the message quickly achieves mass dissemination.

Exploring factors influencing smoking behaviour in Malaysia.

PubMed

Cheah, Yong Kang; Naidu, Balkish Mahadir

2012-01-01

The objective of present study is to investigate the determinants of smoking behaviour among adults in Malaysia. Findings of the Third National Health and Morbidity Survey (NHMS-3) by the Ministry of Health, Malaysia, were used. The sample consisted of 34,539 observations. A logistic regression model was thus applied to estimate the probability to participate in smoking. Age, income, gender, marital status, ethnicity, employment status, residential area, education, lifestyle and health status were statistically significant in affecting the likelihood of smoking. Specifically, youngsters, low income earners, males, unmarried individuals, Malays, employed individuals, rural residents and primary educated individuals were more likely to smoke. In conclusion, socio-demographic, lifestyle and health factors have significant impacts on smoking participation in Malaysia. Based on these empirical findings, several policy implications are suggested.

Influence of processing factors over concrete strength.

NASA Astrophysics Data System (ADS)

Kara, K. A.; Dolzhenko, A. V.; Zharikov, I. S.

2018-03-01

Construction of facilities of cast in-situ reinforced concrete poses additional requirements to quality of material, peculiarities of the construction process may sometimes lead to appearance of lamination planes and inhomogeneity of concrete, which reduce strength of the material and structure as a whole. Technology compliance while working with cast in-situ concrete has a significant impact onto the concrete strength. Such process factors as concrete curing, vibration and compaction of the concrete mixture, temperature treatment, etc., when they are countered or inadequately followed lead to a significant reduction in concrete strength. Here, the authors experimentally quantitatively determine the loss of strength in in-situ cast concrete structures due to inadequate following of process requirements, in comparison with full compliance.

Factors influencing the genesis of neurosurgical technology.

PubMed

Bergman, William C; Schulz, Raymond A; Davis, Deanna S

2009-09-01

For any new technology to gain acceptance, it must not only adequately fill a true need, but must also function optimally within the confines of coexisting technology and concurrently available support systems. As an example, over the first decades of the 20th century, a number of drill designs used to perform cranial bone cuts appeared, fell out of favor, and later reappeared as certain supportive technologies emerged. Ultimately, it was the power source that caused one device to prevail. In contrast, a brilliant imaging device, designed to demonstrate an axial view of the lumbar spine, was never allowed to gain acceptance because it was immediately superseded by another device of no greater innovation, but one that performed optimally with popular support technology. The authors discuss the factors that have bearing on the evolution of neurosurgical technology.

Factors influencing professional life satisfaction among neurologists.

PubMed

Teixeira-Poit, Stephanie M; Halpern, Michael T; Kane, Heather L; Keating, Michael; Olmsted, Murrey

2017-06-19

Predicted shortages in the supply of neurologists may limit patients' access to and quality of care for neurological disorders. Retaining neurologists already in practice provides one opportunity to support the overall supply of practicing neurologists. Understanding factors associated with professional life satisfaction (and dissatisfaction) and implementing policies to enhance satisfaction may encourage neurologists to remain in clinical practice. In this paper, we present results from the first study examining factors associated with professional life satisfaction among a large sample of U.S, neurologists. We collaborated with the AAN to survey a sample of U.S. neurologists about their professional life satisfaction. Analyses examined the association of physician and practice characteristics with aspects of professional life satisfaction, including satisfaction with their career in medicine, medical specialty, current position, relationship with colleagues, relationship with patients, work/life balance, and pay. The study population consisted of 625 neurologists. In multivariate regression analyses, no single group or population stratum indicated high (or low) responses to all aspects of satisfaction. Older neurologists reported higher satisfaction with career, specialty, and relationship with patients than younger neurologists. Female neurologists had significantly lower satisfaction with pay than male neurologists. Neurologists who spent more time in research and teaching had greater satisfaction with specialty, relationship with colleagues, and relationship with patients than those spending no time in research. Neurologists who practiced in small cities/rural areas reported lower satisfaction across multiple dimensions than those practicing in large urban areas. Neurologists in solo practice had greater satisfaction with the relationship with their patients, but lower satisfaction with pay. Satisfaction is a multidimensional construct that is associated with

Factors influencing antioxidant compounds in rice.

PubMed

Goufo, Piebiep; Trindade, Henrique

2017-03-24

Epidemiological and clinical studies suggest that the additive/synergistic effects of several bioactive compounds are responsible for the health benefits of rice. Among the leading contenders are phenolic acids, flavonoids, anthocyanins, proanthocyanidins, tocotrienols, tocopherols, λ-oryzanol, and phytic acid, which all possess strong antioxidant activities in vitro. In this review, data related to health effects of rice antioxidants using cultured cells, rodents and humans models are first summarized. The evidence is strong that consumption of rice tocotrienols translates into improved health outcomes. Current research, however, does not strongly support the health-promoting effects of rice tocopherols and phenolic acids. The crucial limitations in studies using rice flavonoids, anthocyanins, proanthocyanidins, λ-oryzanol and phytic acid appear to be the appropriateness of the substance tested (i.e., purity), and the scarcity of animal and human interventions. In a second part, rice antioxidants are reviewed with an emphasis on their composition and contents. Taking into account the bioavailability of these compounds, it is evident that a number of factors affect the antioxidant composition of rice, making it difficult to estimate dietary intake. Before harvest, factors including soil type, atmospheric CO 2 , chemical inputs, temperature, and degree of ripening are important. After harvest, rice is subjected to processing methods that include drying, parboiling, storage, irradiation, milling, stabilization, soaking, germination, fermentation, boiling, steaming, roasting, baking, and extrusion. Quantitative knowledge about the effects of these processes is summarized in this review. Surprisingly, a high level of agreement was found among study results, which could be useful in manipulating the growing and processing techniques of rice grains to facilitate efficient and safe consumption of antioxidant compounds.

Factors influencing patronage of traditional bone setters.

PubMed

Thanni, L O

2000-01-01

In clinical orthopaedic practice, many patients are seen presenting with complications after being treated by traditional bone setters (TBS). These complications do not seem to deter other patients from patronising the TBS rather than modern orthopaedic service (MOS). Basic beliefs about TBS in particular and traditional healers (TH) in general are likely to be responsible for their continuing popularity. One hundred and eighty adults and adolescents were surveyed by means of interviewer administered questionnaires at a popular motor park, traditional and modern health facilities. While 37% (n = 67) of the respondents believe that TBS are indispensable (cannot do without), 32.8% (n = 65) believe they are desirable (can do without though useful) and 11% (n = 20) thought they are nuisances and fraudsters. Forty three per cent of them felt that TBS are competent or very competent, 24% adjudged their practice satisfactory (good but with some deficiencies) and 23% believe they are either incompetent or very incompetent. Education did not seem to influence these beliefs as the expressed opinion on the indispensability/desirability of TBS by those who had no formal education was similar to that of those who had primary education, p > 0.5, and College/University education, p) 0.1. The services of the TBS were thought to be cheaper (n = 103) than MOS (n = 36) although more (n = 120) believe that doctors explain the causes of injuries and illness rather than TBS (n = 35). The community opinion of TBS, irrespective of educational status, is probably predominantly positive in addition to their services being thought to be cheaper than modern orthopaedic service, hence their continued relevance in the treatment of musculo skeletal injuries and diseases.

Bottom-up factors influencing riparian willow recovery in Yellowstone National Park

USGS Publications Warehouse

Tercek, M.T.; Stottlemyer, R.; Renkin, R.

2010-01-01

After the elimination of wolves (Canis lupis L.) in the 1920s, woody riparian plant communities on the northern range of Yellowstone National Park (YNP) declined an estimated 50%. After the reintroduction of wolves in 19951996, riparian willows (Salix spp.) on YNP's northern range showed significant growth for the first time since the 1920s. However, the pace of willow recovery has not been uniform. Some communities have exceeded 400 cm, while others are still at pre-1995 levels of 250 cm max. height) willow sites where willows had escaped elk (Cervus elaphus L.) browsing with "short" willow sites that could still be browsed. Unlike studies that manipulated willow height with fences and artificial dams, we examined sites that had natural growth differences in height since the reintroduction of wolves. Tall willow sites had greater water availability, more-rapid net soil nitrogen mineralization, greater snow depth, lower soil respiration rates, and cooler summer soil temperatures than nearby short willow sites. Most of these differences were measured both in herbaceous areas adjacent to the willow patches and in the willow patches themselves, suggesting that they were not effects of varying willow height recovery but were instead preexisting site differences that may have contributed to increased plant productivity. Our results agree with earlier studies in experimental plots which suggest that the varying pace of willow recovery has been influenced by abiotic limiting factors that interact with top-down reductions in willow browsing by elk. ?? 2010 Western North American Naturalist.

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.

Factors That Influence Technology Integration in the Classroom

ERIC Educational Resources Information Center

Montgomery, Maureen C.

2017-01-01

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

Factors influencing the, selection of state office furniture

Treesearch

R. Bruce Anderson; R. Bruce Anderson

1973-01-01

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

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

Factors influencing bacterial adhesion to contact lenses.

PubMed

Dutta, Debarun; Cole, Nerida; 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.

FACTORS INFLUENCING HOST-VIRUS INTERACTIONS

PubMed Central

Boring, William D.; Angevine, D. Murray; Walker, Duard L.

1955-01-01

A study was made of the pathogenesis of infection due to the Conn.-5 strain of Coxsackie virus in 4 to 5 day old infant mice, untreated adult mice, and adult mice treated with cortisone. The quantitative distribution of virus and the evolution of lesions in different tissues were followed for the first 7 days of the infection. Virus dissemination was prompt and widespread via the blood in all groups. In 4 to 5 day old infant mice viral multiplication and cellular injury occurred in many organs and tissues, while in untreated adult mice these processes were largely limited to the pancreas, even though infecting virus appeared to be equally available to other tissues from the blood. Treatment of adult mice with a single injection of 2.5 mg. cortisone resulted in viral multiplication and tissue damage in several sites in addition to the pancreas, the most marked occurring in the liver and heart. In a consideration of possible mechanisms involved, it was thought unlikely that the differences in the course of the disease in the three groups could be attributed solely to differences in the specific immune response. It is suggested that developmental changes in cells and tissues, perhaps related to cellular metabolism and alterable by cortisone administration, are the major factors determining the location and extent of viral multiplication and tissue injury in this infection in mice. PMID:13271687

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

Factors Influencing Patient Experience in Pediatric Neurology.

PubMed

Singh, Suprit C; Sheth, Raj D; Burrows, James F; Rosen, Paul

2016-07-01

Hospitals have begun to shift toward patient-centered care because of the pay-for-performance system that was established by the Patient Protection and Affordable Care Act. In pediatrics, the needs of both the caregiver and the pediatric patient have to be taken into account. Pediatric practices have been shifting toward a family-centered approach, although the primary drivers have not been well defined. Identifying the key patient experiences that lead to higher patient satisfaction would enable a more meaningful clinical encounter. To better understand patient experience, we examined waiting time and the elements of the physician-patient interaction in pediatric neurology. We predict that the determining factor in patient satisfaction is the physician-patient interaction. Patient satisfaction surveys were sent to families via mail or e-mail after their ambulatory pediatric neurology visit. The visits took place between January 1, 2012, and December 31, 2014, at one of multiple locations in a children's health system spanning four states. A Likert scale was used for these surveys, and a top-box method (measuring percent of survey questions were rated 5 out of 5) was used to filter data from this database. Statistical analysis using a Pearson correlation was used for data analysis, with likelihood to recommend practice as the dependent variable. The five survey questions that correlated most with overall likelihood to recommend the practice were cheerfulness of practice (r = 0.79); staff working together (r = 0.76); cleanliness of practice (r = 0.70); wait time at clinic, from entering to leaving (r = 0.66); and likelihood of recommending care provider (r = 0.65). Pediatric neurologists striving to enhance overall patient satisfaction in their practices should work toward providing an atmosphere that supports office staff cheerfulness, teamwork, and visit efficiency provided in a clean and friendly environment. Copyright © 2016 Elsevier Inc. All rights

Factors that influence chest injuries in rollovers.

PubMed

Digges, Kennerly; Eigen, Ana; Tahan, Fadi; Grzebieta, Raphael

2014-01-01

The design of countermeasures to reduce serious chest injuries for belted occupants involved in rollover crashes requires an understanding of the cause of these injuries and of the test conditions to assure the effectiveness of the countermeasures. This study defines rollover environments and occupant-to-vehicle interactions that cause chest injuries for belted drivers. The NASS-CDS was examined to determine the frequency and crash severity for belted drivers with serious (Abbreviated Injury Scale [AIS] 3+) chest injuries in rollovers. Case studies of NASS crashes with serious chest injuries sustained by belted front occupants were undertaken and damage patterns were determined. Vehicle rollover tests with dummies were examined to determine occupant motion in crashes with damage similar to that observed in the NASS cases. Computer simulations were performed to further explore factors that could contribute to chest injury. Finite element model (FEM) vehicle models with both the FEM Hybrid III dummy and THUMS human model were used in the simulations. Simulation of rollovers with 6 quarter-turns or less indicated that increases in the vehicle pitch, either positive or negative, increased the severity of dummy chest loadings. This finding was consistent with vehicle damage observations from NASS cases. For the far-side occupant, the maximum chest loadings were caused by belt and side interactions during the third quarter-turn and by the center console loading during the fourth quarter-turn. The results showed that the THUMS dummy produced more realistic kinematics and improved insights into skeletal and chest organ loadings compared to the Hybrid III dummy. These results suggest that a dynamic rollover test to encourage chest injury reduction countermeasures should induce a roll of at least 4 quarter-turns and should also include initial vehicle pitch and/or yaw so that the vehicle's axis of rotation is not aligned with its inertial roll axis during the initial stage

Factors influencing the implementation of evidence in Chinese nursing practice.

PubMed

Cheng, Lei; Broome, Marion E; Feng, Sheng; Hu, Yan

2017-12-01

To explore the influencing factors from staff nurses, nurse managers, nursing directors and a physician involved in nursing evidence implementation in Mainland China. Although the need for evidence-based nursing is well recognised, continuous efforts are needed to strive for closing the gap from evidence to action. Previous studies have explored influencing factors from individual and organisational perspectives in Western countries. However, it remains unclear what the influences (i.e., context and culture) in the developing countries as China. A grounded theory design using in-depth individual interviews was conducted. Interviews with 56 participants from 24 evidence-based nursing implementation projects were conducted in Mainland China. Constant comparative analysis was used to discover the concepts describing the influencing factors during the implementation process. Factors that influenced implementation of evidence-based practice in the Chinese context were identified. These included the leaders of the projects, the nature of the evidence, practising nurses, patients involved in the projects, the system where the projects were implemented, as well as the influence from outside of the system. A variety of factors influencing evidence implementation in Chinese nursing context were identified and further explored from the perspective of different project leaders and culture influence. There is apparently a strong demand for a supportive system, targeted strategies to facilitate various evidence implementations and integrated core elements of evidence-based practice at the point care. The blurred boundaries and complexity of influencing factors call for a systematic and dynamic perspective during implementation. The competitive priorities emphasise the importance of integration between clinical nursing care and evidence-based practice. © 2017 John Wiley & Sons Ltd.

From Hospital to Nursing Facility: Factors Influencing Decisions

ERIC Educational Resources Information Center

Mason, Susan E.; Auerbach, Charles; LaPorte, Heidi Heft

2009-01-01

This study addresses the factors influencing decisions to send medicine-surgical (med-surg) patients home or to nursing facilities (NFs). The sample (n = 7,852) was taken from a large, urban, teaching, med-surg unit where discharges were documented and data collected over a two-and-a-half-year period. Using logistical regression, the factors found…

Exploring Factors Influencing Acceptance and Use of Video Digital Libraries

ERIC Educational Resources Information Center

Ju, Boryung; Albertson, Dan

2018-01-01

Introduction: This study examines the effects of certain key factors on users' intention to ultimately adopt and use video digital libraries for facilitating their information needs. The individual factors identified for this study, based on their given potential to influence use and acceptance of video digital libraries, were categorised for data…

Factors Influencing Dietary Fat Intake among Black Emerging Adults

ERIC Educational Resources Information Center

Horton, Shalonda E. B.; Timmerman, Gayle M.; Brown, Adama

2018-01-01

Objective: To determine what factors influenced dietary fat intake (DFI) among black emerging adults. Participants: Sample included 251 black emerging adults, ages 18-25 years, living in the US. Methods: This was a nonexperimental cross-sectional study based on self-report data. Results: The sample had high DFI. Factors related to DFI were gender…

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).…

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…

Factors that Influence Students' Decision to Dropout of Online Courses

ERIC Educational Resources Information Center

Willging, Pedro A.; Johnson, Scott D.

2009-01-01

Although there are many reasons why students dropout of college courses, those reasons may be unique for students who are enrolled in an online program. Issues of isolation, disconnectedness, and technological problems may be factors that influence a student to leave a course. To understand these factors, an online survey was developed to collect…

Professional Identity Development in Higher Education: Influencing Factors

ERIC Educational Resources Information Center

Barbarà-i-Molinero, Alba; Cascón-Pereira, Rosalía; Hernández-Lara, Ana beatriz

2017-01-01

Purpose: In the last few years, the interest on professional identity development (PID) and the factors that influence PID has become central in higher education (HE) literature. However, the knowledge developed in this domain has focussed on a factor at a time and on a degree or discipline, thus being difficult to have a general picture of all…

Alternative Administrative Certification: Socializing Factors Influencing Program Choice

ERIC Educational Resources Information Center

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

2013-01-01

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

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…

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…

Hierarchical and coupling model of factors influencing vessel traffic flow.

PubMed

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

2017-01-01

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

Factors Influencing Students' Achievement in Form 5 Islamic Studies Subject

ERIC Educational Resources Information Center

bin Che Noh, Mohd Aderi; Omar, Noraini binti; bin Kasan, Hasnan

2013-01-01

This study is aimed at analyzing the factors influencing the achievements of students in the subject of Islamic Studies for Form 5 SPM (KBSM) in schools in the area of Samarahan, Sarawak. The factors analysed is attitude and interest. This is a survey based study and data was compiled from the survey forms which had the topic "Factors…

Hierarchical and coupling model of factors influencing vessel traffic flow

PubMed Central

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

2017-01-01

Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system. PMID:28414747

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…

Analysis of the influencing factors of global energy interconnection development

NASA Astrophysics Data System (ADS)

Zhang, Yi; He, Yongxiu; Ge, Sifan; Liu, Lin

2018-04-01

Under the background of building global energy interconnection and achieving green and low-carbon development, this paper grasps a new round of energy restructuring and the trend of energy technology change, based on the present situation of global and China's global energy interconnection development, established the index system of the impact of global energy interconnection development factors. A subjective and objective weight analysis of the factors affecting the development of the global energy interconnection was conducted separately by network level analysis and entropy method, and the weights are summed up by the method of additive integration, which gives the comprehensive weight of the influencing factors and the ranking of their influence.

Nurturing Sport Expertise: Factors Influencing the Development of Elite Athlete

PubMed Central

Baker, Joseph; Horton, Sean; Robertson-Wilson, Jennifer; Wall, Michael

2003-01-01

The development of expertise in sport is the result of successful interaction of biological, psychological, and sociological constraints. This review examines the training and environmental factors that influence the acquisition of sport expertise. Research examining the quality and quantity of training indicate that these two elements are crucial predictors of attainment. In addition, the possession of resources such as parental support and adequate coaching are essential. Social factors such as cultural influences and the relative age effect are also considered as determinants of sport expertise. Although it is evident that environmental factors are essential to the acquisition of high levels of sport development, further research is clearly required. PMID:24616603

Abiotic stresses affect Trichoderma harzianum T39-induced resistance to downy mildew in grapevine.

PubMed

Roatti, Benedetta; Perazzolli, Michele; Gessler, Cesare; Pertot, Ilaria

2013-12-01

Enhancement of plant defense through the application of resistance inducers seems a promising alternative to chemical fungicides for controlling crop diseases but the efficacy can be affected by abiotic factors in the field. Plants respond to abiotic stresses with hormonal signals that may interfere with the mechanisms of induced systemic resistance (ISR) to pathogens. In this study, we exposed grapevines to heat, drought, or both to investigate the effects of abiotic stresses on grapevine resistance induced by Trichoderma harzianum T39 (T39) to downy mildew. Whereas the efficacy of T39-induced resistance was not affected by exposure to heat or drought, it was significantly reduced by combined abiotic stresses. Decrease of leaf water potential and upregulation of heat-stress markers confirmed that plants reacted to abiotic stresses. Basal expression of defense-related genes and their upregulation during T39-induced resistance were attenuated by abiotic stresses, in agreement with the reduced efficacy of T39. The evidence reported here suggests that exposure of crops to abiotic stress should be carefully considered to optimize the use of resistance inducers, especially in view of future global climate changes. Expression analysis of ISR marker genes could be helpful to identify when plants are responding to abiotic stresses, in order to optimize treatments with resistance inducers in field.

The influence of soil-site factors on sugar maple (Acer saccharum Marsh.) growth response to climatic change in central Ontario

NASA Astrophysics Data System (ADS)

Schutten, K.; Gedalof, Z.

2010-12-01

Over the past several decades, concerns about climatic change and its potential impacts on Canada’s various geographical regions and associated ecological processes have grown steadily, especially among land and resource managers. As these risks transition into tangible outcomes in the field, it will be important for resource managers to understand historical climatic variability and natural ecological trends in order to effectively respond to a changing climate. Sugar maple (Acer saccharum Marsh.) is considered a stable endpoint for mature forests in the northern hardwood community of central Ontario, and it tends to be the dominant species, in a beech-ironwood-yellow birch matrix. In North America, this species is used for both hardwood lumber and for maple sugar (syrup) products; where it dominates, large recreational opportunities also exist. There are many biotic and abiotic factors that play a large role in the growth and productivity of sugar maple stands, such as soil pH, moisture regime, and site slope and aspect. This research undertaking aims to add to the body of literature addressing the following question: how do site factors influence the sensitivity of sugar maple growth to climatic change? The overall objective of the research is to evaluate how biotic and abiotic factors influence the sensitivity of sugar maple annual radial growth to climatic variability. This research will focus on sugar maple growth and productivity in Algonquin Provincial Park, and the impact that climatic variability has had in the past on these stands based on site-specific characteristics. In order to complete this goal, 20 sites were identified in Algonquin Provincial Park based on variability of known soil and site properties. These sites were visited in order to collect biotic and abiotic site data, and to measure annual radial growth increment of trees. Using regional climate records and standard dendrochronological methods, the collected increment growth data will be

Soil respiration in the cold desert environment of the Colorado Plateau (USA): Abiotic regulators and thresholds

USGS Publications Warehouse

Fernandez, D.P.; Neff, J.C.; Belnap, J.; Reynolds, R.L.

2006-01-01

Decomposition is central to understanding ecosystem carbon exchange and nutrient-release processes. Unlike mesic ecosystems, which have been extensively studied, xeric landscapes have received little attention; as a result, abiotic soil-respiration regulatory processes are poorly understood in xeric environments. To provide a more complete and quantitative understanding about how abiotic factors influence soil respiration in xeric ecosystems, we conducted soil- respiration and decomposition-cloth measurements in the cold desert of southeast Utah. Our study evaluated when and to what extent soil texture, moisture, temperature, organic carbon, and nitrogen influence soil respiration and examined whether the inverse-texture hypothesis applies to decomposition. Within our study site, the effect of texture on moisture, as described by the inverse texture hypothesis, was evident, but its effect on decomposition was not. Our results show temperature and moisture to be the dominant abiotic controls of soil respiration. Specifically, temporal offsets in temperature and moisture conditions appear to have a strong control on soil respiration, with the highest fluxes occurring in spring when temperature and moisture were favorable. These temporal offsets resulted in decomposition rates that were controlled by soil moisture and temperature thresholds. The highest fluxes of CO2 occurred when soil temperature was between 10 and 16??C and volumetric soil moisture was greater than 10%. Decomposition-cloth results, which integrate decomposition processes across several months, support the soil-respiration results and further illustrate the seasonal patterns of high respiration rates during spring and low rates during summer and fall. Results from this study suggest that the parameters used to predict soil respiration in mesic ecosystems likely do not apply in cold-desert environments. ?? Springer 2006.

The physicochemical process of bacterial attachment to abiotic surfaces: Challenges for mechanistic studies, predictability and the development of control strategies.

PubMed

Wang, Yi; Lee, Sui Mae; Dykes, Gary

2015-01-01

Bacterial attachment to abiotic surfaces can be explained as a physicochemical process. Mechanisms of the process have been widely studied but are not yet well understood due to their complexity. Physicochemical processes can be influenced by various interactions and factors in attachment systems, including, but not limited to, hydrophobic interactions, electrostatic interactions and substratum surface roughness. Mechanistic models and control strategies for bacterial attachment to abiotic surfaces have been established based on the current understanding of the attachment process and the interactions involved. Due to a lack of process control and standardization in the methodologies used to study the mechanisms of bacterial attachment, however, various challenges are apparent in the development of models and control strategies. In this review, the physicochemical mechanisms, interactions and factors affecting the process of bacterial attachment to abiotic surfaces are described. Mechanistic models established based on these parameters are discussed in terms of their limitations. Currently employed methods to study these parameters and bacterial attachment are critically compared. The roles of these parameters in the development of control strategies for bacterial attachment are reviewed, and the challenges that arise in developing mechanistic models and control strategies are assessed.

Intra-Specific Latitudinal Clines in Leaf Carbon, Nitrogen, and Phosphorus and their Underlying Abiotic Correlates in Ruellia Nudiflora.

PubMed

Abdala-Roberts, Luis; Covelo, Felisa; Parra-Tabla, Víctor; Terán, Jorge C Berny Mier Y; Mooney, Kailen A; Moreira, Xoaquín

2018-01-12

While plant intra-specific variation in the stoichiometry of nutrients and carbon is well documented, clines for such traits have been less studied, despite their potential to reveal the mechanisms underlying such variation. Here we analyze latitudinal variation in the concentration of leaf nitrogen (N), phosphorus (P), carbon (C) and their ratios across 30 populations of the perennial herb Ruellia nudiflora. In addition, we further determined whether climatic and soil variables underlie any such latitudinal clines in leaf traits. The sampled transect spanned 5° latitude (ca. 900 km) and exhibited a four-fold precipitation gradient and 2 °C variation in mean annual temperature. We found that leaf P concentration increased with precipitation towards lower latitudes, whereas N and C did not exhibit latitudinal clines. In addition, N:P and C:P decreased towards lower latitudes and latitudinal variation in the former was weakly associated with soil conditions (clay content and cation exchange capacity); C:N did not exhibit a latitudinal gradient. Overall, these results emphasize the importance of addressing and disentangling the simultaneous effects of abiotic factors associated with intra-specific clines in plant stoichiometric traits, and highlight the previously underappreciated influence of abiotic factors on plant nutrients operating under sharp abiotic gradients over smaller spatial scales.

Review of recent transgenic studies on abiotic stress tolerance and future molecular breeding in potato.

PubMed

Kikuchi, Akira; Huynh, Huu Duc; Endo, Tsukasa; Watanabe, Kazuo

2015-03-01

Global warming has become a major issue within the last decade. Traditional breeding programs for potato have focused on increasing productivity and quality and disease resistance, thus, modern cultivars have limited tolerance of abiotic stresses. The introgression of abiotic stress tolerance into modern cultivars is essential work for the future. Recently, many studies have investigated abiotic stress using transgenic techniques. This manuscript focuses on the study of abiotic stress, in particular drought, salinity and low temperature, during this century. Dividing studies into these three stress categories for this review was difficult. Thus, based on the study title and the transgene property, transgenic studies were classified into five categories in this review; oxidative scavengers, transcriptional factors, and above three abiotic categories. The review focuses on studies that investigate confer of stress tolerance and the identification of responsible factors, including wild relatives. From a practical application perspective, further evaluation of transgenic potato with abiotic stress tolerance is required. Although potato plants, including wild species, have a large potential for abiotic stress tolerance, exploration of the factors responsible for conferring this tolerance is still developing. Molecular breeding, including genetic engineering and conventional breeding using DNA markers, is expected to develop in the future.

A brief review of salient factors influencing adult eating behaviour.

PubMed

Emilien, Christine; Hollis, James H

2017-12-01

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

[Factors influencing research activity of Andalusian nurses and improvement strategies].

PubMed

López Alonso, Sergio R; Gálvez González, María; Amezcua, Manuel

2013-04-01

To identify factors influencing research activity of Andalusian nurses and to find improvement strategies. Qualitative research using SWOT analysis (weaknesses, threats, strengths, opportunities). Nurses were selected deliberately in eight groups according to predetermined criteria. Analysis included categorization and relationship of factors and strategies. 81 participants were included in groups of 7-12 range. 45 categories were identified with 212 factors: 12 weaknesses (50 factors), 10 strengths (44 factors), 12 threats (68 factors) and 11 opportunities (50 factors). In addition, 32 categories were identified with 53 strategies: 14 categories of W-T strategies (42 strategies), 3 categories of S-T strategies (11 strategies), 5 categories of W-O strategies (13 strategies) and 10 categories of S-O strategies (41 strategies). Nurses identified numerous factors, mainly threats. The strategies are focused on W-T but they also suggest many but weak 5-0 strategies due to the low potential of the opportunities and strengths perceived.

Quantitative influence of risk factors on blood glucose level.

PubMed

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

2014-01-01

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

Assessment of Factors Influencing Communication in Clinical Pharmacy.

PubMed

Yao, Dongning; Jiang, Liang; Huang, Yuankai; Chen, Lei; Wang, Yitao; Xi, Xiaoyu

2018-01-01

This study aimed to identify and assess the factors that influence communication quality between clinical pharmacists and patients using a structural equation model based on the predisposing, reinforcing, and enabling constructs in educational/environmental diagnosis and evaluation-policy, regulatory, and organizational constructs in educational and ecological development model to identify the most effective path to increase their communication quality. A survey was conducted at 253 Class-A tertiary hospitals in China from March to December 2016. During on-site observations, verbal communications between clinical pharmacists ( n = 752) and patients were audio recorded, and communication quality was rated by an expert panel on an 8-item Quality of Communication Rating Scale. Clinical pharmacists completed questionnaires that examined the predisposing, enabling, and reinforcing factors that influenced communication quality. Finally, AMOS was employed to examine the relationships between the three factors and communication quality. The results indicated that all three factors positively affected communication quality, with correlation coefficients of .26, .13, and .17, respectively. The most influential predisposing factor was attitude (.77), the most influential enabling factors were self-efficacy (.71) and confidence (.72), and the most influential reinforcing factor was rewards (.74). The findings suggest that pharmacists' attitudes toward, perceived knowledge of, and skill and confidence in communication, and the rewards offered by pharmacy management are the most influential factors that influence communication quality.

Factors That Influence the Practice of Elective Induction of Labor

PubMed Central

Moore, Jennifer; Low, Lisa Kane

2012-01-01

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

Maturity of hospital information systems: Most important influencing factors.

PubMed

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

2017-07-01

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

Factors influencing health information system adoption in American hospitals.

PubMed

Wang, Bill B; Wan, Thomas T H; Burke, Darrell E; Bazzoli, Gloria J; Lin, Blossom Y J

2005-01-01

To study the number of health information systems (HISs), applicable to administrative, clinical, and executive decision support functionalities, adopted by acute care hospitals and to examine how hospital market, organizational, and financial factors influence HIS adoption. A cross-sectional analysis was performed with 1441 hospitals selected from metropolitan statistical areas in the United States. Multiple data sources were merged. Six hypotheses were empirically tested by multiple regression analysis. HIS adoption was influenced by the hospital market, organizational, and financial factors. Larger, system-affiliated, and for-profit hospitals with more preferred provider organization contracts are more likely to adopt managerial information systems than their counterparts. Operating revenue is positively associated with HIS adoption. The study concludes that hospital organizational and financial factors influence on hospitals' strategic adoption of clinical, administrative, and managerial information systems.

Factors influencing soil invertebrate communities in riparian grasslands of the central platte river floodplain

USGS Publications Warehouse

Davis, C.A.; Austin, J.E.; Buhl, D.A.

2006-01-01

In the Platte River Valley of central Nebraska, USA, riparian grasslands (also known as wet meadows) have been severely impacted by a reduction in river flows, causing lower ground-water levels and altered seasonal hydroperiods. The potential impacts of these hydrologic changes, as well as the environmental factors that influence wet meadow soil invertebrate communities, are not well understood. An understanding of the ecological processes that influence these invertebrate communities is crucial for maintaining and restoring wet meadows along the Platte River. Our objectives were to describe the soil invertebrate community of wet meadows throughout the growing season and to examine the relative roles of abiotic factors in determining patterns in invertebrate community structure. We conducted the study in 12 wet meadows along the Platte River during 1999 and 2000. We identified 73 invertebrate taxa; 39 were considered soil inhabitants. Total biomass was primarily composed of earthworms, Scarabaeidae, Isopoda, and Elateridae, with earthworms and Scarabaeidae accounting for >82%. Differences in river flow and precipitation patterns influenced some soil invertebrates. Earthworms and Scarabaeidae declined dramatically from 1999 (wet year) to 2000 (dry year). The topographic gradient created by the ridge-swale complex affected several soil invertebrate taxa; Scarabaeidae, Diplopoda, and Lepidoptera biomasses were greatest on drier ridges, while Tipulidae and Isopoda biomasscs were greatest in wetter sloughs. Responses of earthworm taxa to the topographic gradient were variable, but generally, greater biomasses occurred on ridges and mid-elevations. Water-table depth and soil moisture were the most important variables influencing wet meadow soil invertebrates. Because these communities are linked to the hydrologic processes of the Platte River, future alterations of wet meadow hydrology could shift the distribution patterns of many of these invertebrates and possibly

Factors influencing US medical students' decision to pursue surgery.

PubMed

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

2016-06-01

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

What factors influence British medical students' career intentions?

PubMed

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

2014-12-01

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

Psychosocial factors for influencing healthy aging in adults in Korea.

PubMed

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

2015-03-07

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

Abiotic degradation of plastic films

NASA Astrophysics Data System (ADS)

Ángeles-López, Y. G.; Gutiérrez-Mayen, A. M.; Velasco-Pérez, M.; Beltrán-Villavicencio, M.; Vázquez-Morillas, A.; Cano-Blanco, M.

2017-01-01

Degradable plastics have been promoted as an option to mitigate the environmental impacts of plastic waste. However, there is no certainty about its degradability under different environmental conditions. The effect of accelerated weathering (AW), natural weathering (NW) and thermal oxidation (TO) on different plastics (high density polyethylene, HDPE; oxodegradable high density polyethylene, HDPE-oxo; compostable plastic, Ecovio ® metalized polypropylene, PP; and oxodegradable metalized polypropylene, PP-oxo) was studied. Plastics films were exposed to AW per 110 hours; to NW per 90 days; and to TO per 30 days. Plastic films exposed to AW and NW showed a general loss on mechanical properties. The highest reduction in elongation at break on AW occurred to HDPE-oxo (from 400.4% to 20.9%) and was higher than 90% for HDPE, HDPE-oxo, Ecovio ® and PP-oxo in NW. No substantial evidence of degradation was found on plastics exposed to TO. Oxo-plastics showed higher degradation rates than their conventional counterparts, and the compostable plastic was resistant to degradation in the studied abiotic conditions. This study shows that degradation of plastics in real life conditions will vary depending in both, their composition and the environment.

Factors influencing epibenthic assemblages in the Minho Estuary (NW Iberian Peninsula).

PubMed

Costa-Dias, Sérgia; Freitas, Vânia; Sousa, Ronaldo; Antunes, Carlos

2010-01-01

The epibenthic community of the Minho Estuary was studied during the summer of 2006. Diversity was generally low and a total of 14 fish and five crustacean taxa were identified. Multivariate analysis revealed two site clusters (A and B). Water conductivity and percentage of fine sand were the abiotic variables that most contributed to the spatial distinction between clusters. The species contributing the most to the average similarity within Cluster A were Crangon crangon and Pomatoschistus microps, while in Cluster B was Atyaephyra desmarestii. Possible factors responsible for the low diversity of the epibenthic community in Minho Estuary were the low macrozoobenthic abundance and diversity, and the high abiotic oscillations between tides (mainly salinity) acting on the ecosystem. Copyright 2010 Elsevier Ltd. All rights reserved.

Factors that influence the childbearing intentions of Canadian men.

PubMed

Roberts, E; Metcalfe, A; Jack, M; Tough, S C

2011-05-01

The role of men in the childbearing decision process and the factors that influence men's childbearing intentions have been relatively unexplored in the literature. This study aimed to describe the factors that strongly influence the childbearing intentions of men and to describe differences in these factors according to men's age group. A telephone survey (response rate 84%) was conducted with 495 men between the ages of 20 and 45 living in an urban setting who, at the time of contact, did not have biological children. Men were asked about what factors strongly influence their intention to have children. Univariable and multivariable logistic regressions were conducted to determine if these factors were significantly associated with age. Of those sampled, 86% of men reported that at some point in the future they planned to become a parent. The factors that men considered to be most influential in their childbearing intentions were: the need to be financially secure, their partner's interest/desire to have children, their partner's suitability to be a parent and their personal interest/desire to have children. Men who were 35-45 years old had lower odds of stating that financial security (crude OR: 0.32, 95% CI: 0.18-0.54) and partner's interest in having children (crude OR: 0.57, 95% CI: 0.33-0.99) were very influential, but had higher odds of stating that their biological clock (crude OR: 4.37, 95% CI: 1.78-10.76) was very influential in their childbearing intentions than men in the 20-24 year age group. The factors that influence men's intentions about when to become a parent may change with age. Understanding what influences men to have children, and what they understand about reproductive health is important for education, program and policy development.

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

PubMed

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

2018-03-20

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

Factors influencing return to work after illness in France.

PubMed

Pélissier, C; Fontana, L; Chauvin, F

2014-01-01

Few studies have been published about the factors influencing return to work after sickness absence. To identify medical and occupational factors influencing the type of fitness certificate given by occupational physicians before employees return to work after sickness absence. A cross-sectional study was undertaken over 3 months in several health services in France. Workers undergoing a medical examination before returning to work after a period of sickness absence of at least 3 weeks were included. Medical and occupational factors were collected using a questionnaire. The relationship between different factors and certification of fitness was assessed by univariate and multivariate analyses. Among the 402 workers included, 64% were considered fit to return to work. Being older, strenuous work, prolonged sick leave and fear of returning to work appeared to be negative factors influencing the return to a previous job. In contrast, having an education level higher than secondary school, being satisfied at work, perception of very good health and benefitting from satisfactory professional relationships appeared to favour return to work. We developed a predictive score of not being fit to return to work after illness. Our study highlighted the relationship between medical and occupational factors with problems returning to work. The predictive score may be used by occupational physicians as a screening tool to identify those who are likely to have difficulties returning to work after illness, so that their working conditions can be modified to take this into consideration.

Cerebrospinal Fluid Pressure: Revisiting Factors Influencing Optic Nerve Head Biomechanics

PubMed Central

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

2018-01-01

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

Resistance Responses of Potato to Vesicular-Arbuscular Mycorrhizal Fungi under Varying Abiotic Phosphorus Levels.

PubMed

McArthur, D A; Knowles, N R

1992-09-01

In mycorrhizal symbioses, susceptibility of a host plant to infection by fungi is influenced by environmental factors, especially the availability of soil phosphorus. This study describes morphological and biochemical details of interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants, with a particular focus on the physiological basis for P-induced resistance of roots to infection. Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis. The capacity of excised roots from P-deficient plants to produce ethylene in the presence or absence of exogenous 1-amino cyclopropane-1-carboxylic acid (ACC) was markedly reduced by VAM infection. This apparent inhibition of ACC oxidase (ACC(ox)) activity was localized to areas containing infected roots, as demonstrated in split-root studies. Furthermore, leachate from VAM roots contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC by nonmycorrhizal (NM) roots. The leachate from VAM-infected roots had a higher concentration of phenolics, relative to that from NM roots. Moreover, the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature. The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots. Polyphenol oxidase activity of roots did not differ between NM and VAM roots. These results characterize the low resistance response of P-deficient plants to VAM infection. When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis

Resistance Responses of Potato to Vesicular-Arbuscular Mycorrhizal Fungi under Varying Abiotic Phosphorus Levels 1

PubMed Central

McArthur, David A. J.; Knowles, N. Richard

1992-01-01

In mycorrhizal symbioses, susceptibility of a host plant to infection by fungi is influenced by environmental factors, especially the availability of soil phosphorus. This study describes morphological and biochemical details of interactions between a vesicular-arbuscular mycorrhizal (VAM) fungus and potato (Solanum tuberosum L. cv Russet Burbank) plants, with a particular focus on the physiological basis for P-induced resistance of roots to infection. Root infection by the VAM fungus Glomus fasciculatum ([Thaxt. sensu Gerdemann] Gerdemann and Trappe) was extensive for plants grown with low abiotic P supply, and plant biomass accumulation was enhanced by the symbiosis. The capacity of excised roots from P-deficient plants to produce ethylene in the presence or absence of exogenous 1-amino cyclopropane-1-carboxylic acid (ACC) was markedly reduced by VAM infection. This apparent inhibition of ACC oxidase (ACCox) activity was localized to areas containing infected roots, as demonstrated in split-root studies. Furthermore, leachate from VAM roots contained a potent water-soluble inhibitor of ethylene generation from exogenous ACC by nonmycorrhizal (NM) roots. The leachate from VAM-infected roots had a higher concentration of phenolics, relative to that from NM roots. Moreover, the rates of ethylene formation and phenolic concentration in leachates from VAM roots were inversely correlated, suggesting that this inhibitor may be of a phenolic nature. The specific activity of extracellular peroxidase recovered in root leachates was not stimulated by VAM infection, although activity on a fresh weight basis was significantly enhanced, reflecting the fact that VAM roots had higher protein content than NM roots. Polyphenol oxidase activity of roots did not differ between NM and VAM roots. These results characterize the low resistance response of P-deficient plants to VAM infection. When plants were grown with higher abiotic P supply, the relative benefit of the VAM symbiosis

Factors Influencing Resident Choice of Prosthodontic Residency Program.

PubMed

Wojnarwsky, Pandora Keala Lee; Wang, Yan; Shah, Kumar; Koka, Sreenivas

2017-06-01

The decision by prosthodontic residency program directors to employ the Match process highlights the need to understand applicant priorities that influence their choice of which programs to rank highly. The purpose of this study is to determine the factors that were most important to residents when choosing from among nonmilitary based prosthodontics dental residency programs in the United States. Following completion of a pilot study, all currently enrolled prosthodontic residents at nonmilitary residency programs were invited to participate via the internet. The study consisted of a survey instrument asking residents to rank 26 possible factors that might impact an applicant's choice of residency program. In addition, the instrument collected other possible influencing variables including gender and debt load. Mean rank scores were compared to determine the most and least important factors. Kruskal-Wallis test was used to compare specific factors between the possible influencing variables. Two hundred and thirty residents completed the survey instrument, representing a 54.1% response rate of possible participants. With regard to factors influencing program choice, reputation of the residency program was the factor ranked the highest by participants, followed in descending order by the program director's personality, curriculum content, access to use of the latest digital technology, and opportunities for dental implant placement. Quality of schools for children, community outreach opportunities, and the ability to moonlight were ranked as the least important factors. Male and female residents ranked factors such as tuition/stipend, curriculum content, and community outreach opportunities significantly differently. Depending on debt load, residents ranked the factors tuition/stipend, ability to moonlight, curriculum content, and safety of the area where the program is differently. Current prosthodontic residents valued the reputation of the program as the most

Factors Influencing the College Choice Decisions of Graduate Students.

ERIC Educational Resources Information Center

Kallio, Ruth E.

1995-01-01

A study investigated the relative importance of 31 institutional characteristics in 1,068 graduate students' decisions to enroll or not enroll in the institution. Factors having the greatest influence included residency status, quality and other academic environment characteristics, work-related concerns, spouse considerations, financial aid, and…

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.…

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…

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…

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…

Factors Influencing the Readability of Student-Generated Texts.

ERIC Educational Resources Information Center

Allen, JoBeth

An investigation examined student-generated texts in terms of both traditional and more theoretically valid readability to determine what factors influence comprehension when children read their own, peer, and adult-written texts. Seventy dictated stories created in an earlier study, along with 4 first-grade level stories from the "Reader's…

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…

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…

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…

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…

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…

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)

An Analysis of Selected Factors Influencing Enrollment Patterns.

ERIC Educational Resources Information Center

Heck, James

This report presents an analysis of factors influencing enrollment patterns at Lake City Community College (LCCC; Florida) and recommends ways to increase enrollments at the college. Section I reviews the methods of collecting data for the report, which included interviews with key college personnel, an examination of social indicators such as…

Some Factors Influencing Air Force Simulator Training Effectiveness. Technical Report.

ERIC Educational Resources Information Center

Caro, Paul W.

A study of U.S. Air Force simulator training was conducted to identify factors that influence the effectiveness of such training and to learn how its effectiveness is being determined. The research consisted of a survey of ten representative Air Force simulator training programs and a review of the simulator training research literature. A number…

Factors That Influence Alumni Major Giving at Doctoral Research Universities

ERIC Educational Resources Information Center

Dean, Michael S.

2007-01-01

The purpose of this study was to investigate the perceptions of chief development officers about the influence of socio-demographic, alumni involvement, and student experience factors of alumni on major giving to higher education institutions. This study also involved the investigation of differences between institutions with respect to…

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…

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…

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…

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,…

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.…

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…

Organizational factors influencing successful primary care and public health collaboration.

PubMed

Valaitis, Ruta; Meagher-Stewart, Donna; Martin-Misener, Ruth; Wong, Sabrina T; MacDonald, Marjorie; O'Mara, Linda

2018-06-07

Public health and primary care are distinct sectors within western health care systems. Within each sector, work is carried out in the context of organizations, for example, public health units and primary care clinics. Building on a scoping literature review, our study aimed to identify the influencing factors within these organizations that affect the ability of these health care sectors to collaborate with one another in the Canadian context. Relationships between these factors were also explored. We conducted an interpretive descriptive qualitative study involving in-depth interviews with 74 key informants from three provinces, one each in western, central and eastern Canada, and others representing national organizations, government, or associations. The sample included policy makers, managers, and direct service providers in public health and primary care. Seven major organizational influencing factors on collaboration were identified: 1) Clear Mandates, Vision, and Goals; 2) Strategic Coordination and Communication Mechanisms between Partners; 3) Formal Organizational Leaders as Collaborative Champions; 4) Collaborative Organizational Culture; 5) Optimal Use of Resources; 6) Optimal Use of Human Resources; and 7) Collaborative Approaches to Programs and Services Delivery. While each influencing factor was distinct, the many interactions among these influences are indicative of the complex nature of public health and primary care collaboration. These results can be useful for those working to set up new or maintain existing collaborations with public health and primary care which may or may not include other organizations.

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…

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…

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…

Factors influencing occupancy of nest cavities in recently burned forests

Treesearch

Victoria A. Saab; Jonathan Dudley; William L. Thompson

2004-01-01

Recently burned forests in western North America provide nesting habitat for many species of cavity-nesting birds. However, little is understood about the time frame and the variables affecting occupancy of postfire habitats by these birds. We studied factors influencing the occupancy and reuse of nest cavities from 1–7 years after fire in two burned sites of western...

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…

Key Factors that Influence Recruiting Young Chinese Students

ERIC Educational Resources Information Center

Wang, Zhenmin

2007-01-01

The discussion in this paper is based on the assumption that international education is equated to recruiting and educating international students, even though its true concept goes far beyond this narrow understanding. The purpose of this research is to look at the key factors that influence recruiting young Chinese students, and make sure all…

Factors Influencing Trainee Participation in Computer Software Applications Training.

ERIC Educational Resources Information Center

Alexander, Melody Webler

1993-01-01

Participants (n=130) who had completed training in WordPerfect, Lotus 1-2-3, and dBase III+ completed a questionnaire related to demographic characteristics and factors that influence training participation. Trainees are participating in computer training for personal reasons, seeking convenient time, location, and length. Child care or…

Factors Influencing Students' Decisions about Post-Year 10 Education

ERIC Educational Resources Information Center

Beswick, Kim; Hay, Ian; Watson, Jane; Allen, Jeanne; Cranston, Neil

2012-01-01

This paper reports pilot data from an instrument devised as part of a large ARC funded project that aims, among other things, to investigate factors that influence the decisions of students in rural and/or disadvantaged areas to continue their schooling beyond Year 10. One section of the pilot student questionnaire comprised 42 items designed to…

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.

Profiling contextual factors which influence safety in heavy vehicle industries.

PubMed

Edwards, Jason R D; Davey, Jeremy; Armstrong, Kerry A

2014-12-01

A significant proportion of worker fatalities within Australia result from truck-related incidents. Truck drivers face a number of health and safety concerns. Safety culture, viewed here as the beliefs, attitudes and values shared by an organisation's workers, which interact with their surrounding context to influence behaviour, may provide a valuable lens for exploring safety-related behaviours in heavy vehicle operations. To date no major research has examined safety culture within heavy vehicle industries. As safety culture provides a means to interpret experiences and generate behaviour, safety culture research should be conducted with an awareness of the context surrounding safety. The current research sought to examine previous health and safety research regarding heavy vehicle operations to profile contextual factors which influence health and safety. A review of 104 peer-reviewed papers was conducted. Findings of these papers were then thematically analysed. A number of behaviours and scenarios linked with crashes and non-crash injuries were identified, along with a selection of health outcomes. Contextual factors which were found to influence these outcomes were explored. These factors were found to originate from government departments, transport organisations, customers and the road and work environment. The identified factors may provide points of interaction, whereby culture may influence health and safety outcomes. Copyright © 2014. Published by Elsevier Ltd.

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%)…

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…

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…

Pantomime Production by People with Aphasia: What Are Influencing Factors?

ERIC Educational Resources Information Center

van Nispen, Karin; van de Sandt-Koenderman, Mieke; Mol, Lisette; Krahmer, Emiel

2016-01-01

Purpose: The present article aimed to inform clinical practice on whether people with aphasia (PWA) deploy pantomime techniques similarly to participants without brain damage (PWBD) and if not, what factors influence these differences. Method: We compared 38 PWA to 20 PWBD in their use of 6 representation techniques ("handling,"…

Factors That Influence the Attrition of Mentors in Rural Areas

ERIC Educational Resources Information Center

Givens, Sharon Leenese

2012-01-01

This research is a qualitative case study exploring the factors that influence the attrition of mentors in rural areas. Mentoring initiatives and programs have proliferated throughout schools in an effort to provide students with positive role models, increase graduation rates and improve overall performance Mentoring programs are an increasingly…

Factors Influencing Females' Access to the High School Principalship

ERIC Educational Resources Information Center

Kruse, Rae Ann

2012-01-01

Scope and Method of Study: The purpose of this study was to identify the factors influencing females' access to the Oklahoma secondary school principalship. Although in the United States federal laws and policies are in place to promote equity, research indicates females are underrepresented in secondary school administration. Regardless of equity…

Factors That Influence the Understanding of Good Mathematics Teaching

ERIC Educational Resources Information Center

Leong, Kwan Eu

2013-01-01

This study explored the factors that influenced the understanding of good mathematics teaching. A mixed methodology was used investigate the beliefs of beginning secondary teachers on good mathematics teaching. The two research instruments used in this study were the survey questionnaire and an interview. Beginning teachers selected Immediate…

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…

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…

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…

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…

The Modeling of Factors That Influence Coast Guard Manpower Requirements

DTIC Science & Technology

2014-12-01

applications, and common data warehouses needed to fully develop an effective and efficient manpower requirements engineering and management program. The... manpower requirements determination ensures a ready force, and safe and effective mission execution. Shortage or excess of manpower is the catalyst...FACTORS THAT INFLUENCE COAST GUARD MANPOWER REQUIREMENTS by Kara M. Lavin December 2014 Thesis Advisor: Ronald E. Giachetti Co-Advisor

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.

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.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Prevalence and influence factors of hypertension among mechanic factory workers].

PubMed

Pang, Li-Juan; Chen, Li-Zhang; Fu, Ben-Yan

2005-06-01

To determine the status and influence factors of hypertension on mechanic factory workers and to provide reference for further hypertension prevention and control. A cross-sectional study on 1205 workers (exposed to different noise levels) in Hunan was carried out by using questionaire and measuring the blood pressure of the workers and the noise exposure level in the workplace. The prevalence and the influence factors of hypertension among mechanic factory workers were analysed. The hypertension prevalence was 12.1%. Logistic regression analysis showed the body weight index (BMI), age, and history of hypertension in parents and accumulative noise dose levels influenced the hypertension prevalence. Controlling the body weight, reducing alcohol consumption, decreasing the sound pressure level in workshops and advocating healthy diet may reduce the prevalence rate of hypertension among mechanic factory workers.

Motivating Factors Influencing College Students' Choice of Academic Major

PubMed Central

Brocavich, Joseph M.; Boone, R. Thomas; Pal, Somnath

2010-01-01

Objectives To assess the factors, motivations, and nonacademic influences that affected the choice of major among pharmacy and nonpharmacy undergraduate students. Methods A survey was administered to 618 pharmacy and nonpharmacy majors to assess background and motivational factors that may have influenced their choice of major. The sample consisted of freshman and sophomore students enrolled in a required speech course. Results African-American and Hispanic students were less likely to choose pharmacy as a major than Caucasians, whereas Asian-Americans were more likely to choose pharmacy as a major. Pharmacy students were more likely to be interested in science and math than nonpharmacy students. Conclusion Students' self-reported racial/ethnic backgrounds influence their decision of whether to choose pharmacy as their academic major. Results of this survey provide further insight into developing effective recruiting strategies and enhancing the marketing efforts of academic institutions. PMID:20498739

Influence of Terraced area DEM Resolution on RUSLE LS Factor

NASA Astrophysics Data System (ADS)

Zhang, Hongming; Baartman, Jantiene E. M.; Yang, Xiaomei; Gai, Lingtong; Geissen, Viollette

2017-04-01

Topography has a large impact on the erosion of soil by water. Slope steepness and slope length are combined (the LS factor) in the universal soil-loss equation (USLE) and its revised version (RUSLE) for predicting soil erosion. The LS factor is usually extracted from a digital elevation model (DEM). The grid size of the DEM will thus influence the LS factor and the subsequent calculation of soil loss. Terracing is considered as a support practice factor (P) in the USLE/RUSLE equations, which is multiplied with the other USLE/RUSLE factors. However, as terraces change the slope length and steepness, they also affect the LS factor. The effect of DEM grid size on the LS factor has not been investigated for a terraced area. We obtained a high-resolution DEM by unmanned aerial vehicles (UAVs) photogrammetry, from which the slope steepness, slope length, and LS factor were extracted. The changes in these parameters at various DEM resolutions were then analysed. The DEM produced detailed LS-factor maps, particularly for low LS factors. High (small valleys, gullies, and terrace ridges) and low (flats and terrace fields) spatial frequencies were both sensitive to changes in resolution, so the areas of higher and lower slope steepness both decreased with increasing grid size. Average slope steepness decreased and average slope length increased with grid size. Slope length, however, had a larger effect than slope steepness on the LS factor as the grid size varied. The LS factor increased when the grid size increased from 0.5 to 30-m and increased significantly at grid sizes >5-m. The LS factor was increasingly overestimated as grid size decreased. The LS factor decreased from grid sizes of 30 to 100-m, because the details of the terraced terrain were gradually lost, but the factor was still overestimated.

Factors influencing warfarin control in Australia and Singapore.

PubMed

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

2017-09-01

Warfarin is widely used for patients with non-valvular atrial fibrillation (NVAF). Variations in warfarin control, as measured by time in therapeutic range (TTR), have been reported across different regions and ethnicities, particularly between Western and Asian countries. However, there is limited data on comparative factors influencing warfarin control in Caucasian and Asian patients. Therefore, the aim of this study was to determine warfarin control and potential factors influencing this in patients with NVAF in Australia and Singapore. Retrospective data was collected for patients receiving warfarin for January to June 2014 in Australia and Singapore. TTR was calculated for individuals with mean patient TTR used for analysis. Possible influential factors on TTR were analysed including age, gender, concurrent co-morbidities, and concurrent medication. The mean TTR was significantly higher in Australia (82%) than Singapore (58%). At both sites, chronic kidney disease significantly lowered this TTR. Further factors influencing control were anaemia and age<60years in Australia, and vascular disease, CHA 2 DS 2 -VASc score of 6, and concurrent platelet inhibitor therapy in Singapore. Warfarin control was significantly higher in Australia compared to Singapore, however chronic kidney disease reduced control at both sites. The different levels of control in these two countries, together with patient factors further reducing control may impact on anticoagulant choice in these countries with better outcomes from warfarin in Australia compared to Singapore. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Why neurology? Factors which influence career choice in neurology.

PubMed

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

2016-01-01

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

The Role of Tomato WRKY Genes in Plant Responses to Combined Abiotic and Biotic Stresses

PubMed Central

Bai, Yuling; Sunarti, Sri; Kissoudis, Christos; Visser, Richard G. F.; van der Linden, C. G.

2018-01-01

In the field, plants constantly face a plethora of abiotic and biotic stresses that can impart detrimental effects on plants. In response to multiple stresses, plants can rapidly reprogram their transcriptome through a tightly regulated and highly dynamic regulatory network where WRKY transcription factors can act as activators or repressors. WRKY transcription factors have diverse biological functions in plants, but most notably are key players in plant responses to biotic and abiotic stresses. In tomato there are 83 WRKY genes identified. Here we review recent progress on functions of these tomato WRKY genes and their homologs in other plant species, such as Arabidopsis and rice, with a special focus on their involvement in responses to abiotic and biotic stresses. In particular, we highlight WRKY genes that play a role in plant responses to a combination of abiotic and biotic stresses.

Influence of psychological factors on the acceptance of complete dentures.

PubMed

al Quran, F; Clifford, T; Cooper, C; Lamey, P J

2001-07-01

To assess the influence of psychological factors on the acceptance of complete dentures in a population wearing dentures judged to be clinically satisfactory. Subjects were asked to complete personality profiles and also to rate their dentures using a denture satisfaction questionnaire. The survey was conducted in the prosthetics clinic of a teaching hospital. Patients were selected from those who had new complete dentures constructed in the department within the previous two years. The personality inventory was a self-administered questionnaire comprising 240 items covering the five domains of personality. Denture satisfaction was scored on a nine item scale with four Likert type responses to each. A group of 16% consistently complained about their dentures. Statistical analysis showed that personality factors especially Neuroticism had a significant relationship with denture satisfaction. Psychological factors significantly influence denture satisfaction and profiles may provide useful in predicting potential difficult denture wearers.

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.

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Factors Influencing the Effectiveness of Inventory Management in Manufacturing SMEs

NASA Astrophysics Data System (ADS)

Chan, Shiau Wei; Tasmin, R.; Nor Aziati, A. H.; Zuraidah Rasi, Raja; Ismail, Fadillah Binti; Yaw, Li Ping

2017-08-01

Effectiveness of inventory management is a vital part in the manufacturing organization to be more competitive. The previous studies have indicated that there are several factors influencing the effectiveness of inventory management in the organization but there is lack of researchers who carried out the research in the manufacturing small medium enterprise in Johor. Therefore, the purpose of this research is to identify the problem of inventory management faced by the manufacturing small medium enterprise and also to determine the factors that will influence the effectiveness of inventory management. In completing this research, 80 employees were selected randomly from the manufacturing small medium enterprise in Batu Pahat, Johor and they were requested to complete questionnaires. The result have shown that the problems of inventory management faced by manufacturing organization were underproduction, overproduction, stock out situation, delays in the delivery of raw materials and discrepancy of records. The factors, documentation/store records, planning, knowledge of employees/staff skill have shown to significantly influence the effectiveness of inventory management while the funds have shown slightly significant influence on the inventory management in manufacturing small medium enterprises. This quantitative study is important to the manufacturing organization in Malaysia because it provides the guidelines to the employers of manufacturing small medium enterprises in Batu Pahat, Johor.

Factors influencing women's decisions about timing of motherhood.

PubMed

Benzies, Karen; Tough, Suzanne; Tofflemire, Karen; Frick, Corine; Faber, Alexandra; Newburn-Cook, Christine

2006-01-01

To examine the factors that influence women's decisions about the timing of motherhood from a life span perspective. Qualitative. Large Western Canadian city with a high rate of infants born to women aged 35 years and older. 45 Canadian women aged 20 to 48 years. Independence, a stable relationship, and declining fertility influenced women's decisions about the timing of motherhood. Women integrated child developmental transitions into a projected life plan as they considered the timing of motherhood. Partner readiness and family of origin influences played a lesser role. Delayed childbearing has become more socially acceptable, with subsequent negative connotations associated with younger motherhood. Parental benefits have limited influence on the timing of motherhood. Recognition by nurses of the various and complex factors that influence women's decisions about the timing of motherhood may flag the importance of pregnancy-related counseling for woman across the fertility life span. Policy decision makers must be cognizant of the need for additional high-risk obstetric and neonatal health services when societal norms encourage women to delay childbearing in favor of completing education and establishing a career. (c) 2006, AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses

Hydrologic, abiotic and biotic interactions: plant density, windspeed, leaf size and groundwater all affect oak water use efficiency

Treesearch

Darin J. Law; Deborah M. Finch

2011-01-01

Plant water use in drylands can be complex due to variation in hydrologic, abiotic and biotic factors, particularly near ephemeral or intermittent streams. Plant use of groundwater may be important but is usually uncertain. Disturbances like fire contribute to complex spatiotemporal heterogeneity. Improved understanding of how such hydrologic, abiotic, and biotic...

Soil heterogeneity in Mojave Desert shrublands: Biotic and abiotic processes

NASA Astrophysics Data System (ADS)

Caldwell, Todd G.; Young, Michael H.; McDonald, Eric V.; Zhu, Jianting

2012-09-01

Geological and ecological processes play critical roles in the evolution of desert piedmonts. Feedback between fast cyclic biotic and slow cumulative pedogenic processes on arid alluvial fan systems results in a heterogeneous landscape of interspace and canopy microsites. Defining the spatial extent between these processes will allow a better connection to ecosystem service and climate change. We use a soil chronosequence in the Mojave Desert and high spatial resolution infiltrometer measurements along transects radiating from canopies of perennial shrubs to assess the extent of biotic and abiotic processes and the heterogeneity of soil properties in arid shrublands. Results showed higher saturated conductivity under vegetation regardless of surface age, but it was more conspicuous on older, developed soils. At proximal locations to the shrub, bulk density, soil structure grade, silt, and clay content significantly increased radially from the canopy, while sand and organic material decreased. Soil properties at distal locations 2-5 times the canopy radius had no significant spatial correlation. The extent of the biotic influence of the shrub was 1.34 ± 0.32 times the canopy radius. Hydraulic properties were weakly correlated in space, but 75% of the variance could be attributed to sand content, soil structure grade, mean-particle diameter, and soil organic material, none of which are exclusively biotic or abiotic. The fast cyclic biotic processes occurring under vegetation are clearly overprinted on slow cumulative abiotic processes, resulting in the deterministic variability observed at the plant scale.

Review on Factors Influencing Physician Guideline Adherence in Cardiology.

PubMed

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

2018-04-09

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

Factors influencing societal response of nanotechnology: an expert stakeholder analysis

NASA Astrophysics Data System (ADS)

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

2012-05-01

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

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

PubMed

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

2012-05-01

Nanotechnology can be described as an emerging technology and, as has been the case with other emerging technologies such as genetic modification, different socio-psychological factors will potentially influence societal responses to its development and application. These factors will play an important role in how nanotechnology is developed and commercialised. This article aims to identify expert opinion on factors influencing societal response to applications of nanotechnology. Structured interviews with experts on nanotechnology from North West Europe were conducted using repertory grid methodology in conjunction with generalized Procrustes analysis to examine the psychological constructs underlying societal uptake of 15 key applications of nanotechnology drawn from different areas (e.g. medicine, agriculture and environment, chemical, food, military, sports, and cosmetics). Based on expert judgement, the main factors influencing societal response to different applications of nanotechnology will be the extent to which applications are perceived to be beneficial, useful, and necessary, and how 'real' and physically close to the end-user these applications are perceived to be by the public. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11051-012-0857-x) contains supplementary material, which is available to authorized users.

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...

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...

Anxiety as a factor influencing physiological effects of acupuncture.

PubMed

Vickland, Victor; Rogers, Carole; Craig, Ashley; Tran, Yvonne

2009-08-01

This study investigated the influence of manual acupuncture on heart rate variability and the role which anxiety can play in modifying physiological outcomes. Analysis of heart rate variability (HRV) was used as a sensitive and a reliable indicator of the balance between sympathetic and parasympathetic regulation of the heartbeat. Two groups of healthy female subjects were recruited into the study. The control group (n=30) attended one experimental session where no acupuncture treatment was used. The experimental group (n=30) attended three sessions in which unilateral manual stimulation of acupuncture points LU7 and KD6 was performed. The stimulation of the acupuncture points LU7 and KD6 was not associated with significant changes in HRV. Previous familiarity with acupuncture did not influence the outcomes but level of anxiety had a strong impact on physiological outcomes. Stimulation of LU7 acupuncture point counterbalanced naturally occurring sympathetic increase over time and had relaxing and harmonizing effect on the heart rhythm without influencing subjective perception of increased anxiety. Stimulation of KD6 acupuncture point had sympathetic influence on HRV in subjects with low "trait" anxiety and this influence was nullified by simultaneous stimulation of LU7 acupuncture point. It seems likely that the level of anxiety can modify HRV during acupuncture treatment and up to 40 min after the treatment. Psychological factors such as anxiety level should be considered as having important influence on physiological response to acupuncture.

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.

External and internal factors influencing happiness in elite collegiate athletes.

PubMed

Denny, Katherine G; Steiner, Hans

2009-03-01

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 student-athletes (N=140) were studied with a standardized questionnaire which examined internal factors ((1) locus of control, (2) mindfulness, (3) self-restraint, and (4) self-esteem) to see whether they better account for happiness than external factors (playing time, scholarship). As predicted, internal factors were more powerful correlates of happiness when holding constant demographics. Regression models differed for different aspects of happiness, but the main postulated result of internal versus external was maintained throughout. These findings have implications for how well athletes cope with adversity which, in turn, could shed light on the development of traits that may provide a buffer against adversity and build resilience.

Factor Influencing Creative Industries Development in Kenjeran Surabaya

NASA Astrophysics Data System (ADS)

Siswanto, V. K.; Santoso, E. B.

2017-07-01

Indonesia needs to improve the competitiveness of local products to optimize its contribution to the ASEAN Economic Community (AEC) for the welfare of the population. This can be done by improving the development of creative industries. Kenjeran Sub District is one of the coastal villages in the city of Surabaya, which has a large number of poor people. The potential of the creative industries is still not visible in efforts to increase public welfare. Therefore, it is necessary to investigate the factors that influence the development of creative industries in Kenjeran. This study using in-depth interview were analysed using content analysis and Cartesian diagram to determine the important factors that affect the development of creative industries in Sub district of Kenjeran. By using five respondents from the government shows that the factors that have a high level of importance and advantages are low among other regulatory factors of raw materials, import and export, extortion, and administrative procedures.

From shared care to disease management: key-influencing factors

PubMed Central

Eijkelberg, Irmgard M.J.G.; Spreeuwenberg, Cor; Mur-Veeman, Ingrid M.; Wolffenbuttel, Bruce H.R.

2001-01-01

Abstract Background In order to improve the quality of care of chronically ill patients the traditional boundaries between primary and secondary care are questioned. To demolish these boundaries so-called ‘shared care’ projects have been initiated in which different ways of substitution of care are applied. When these projects end, disease management may offer a solution to expand the achieved co-operation between primary and secondary care. Objective Answering the question: What key factors influence the development and implementation of shared care projects from a management perspective and how are they linked? Theory The theoretical framework is based on the concept of the learning organisation. Design Reference point is a multiple case study that finally becomes a single case study. Data are collected by means of triangulation. The studied cases concern two interrelated Dutch shared care projects for type 2 diabetic patients, that in the end proceed as one disease management project. Results In these cases the predominant key-influencing factors appear to be the project management, commitment and local context, respectively. The factor project management directly links the latter two, albeit managing both appear prerequisites to its success. In practice this implies managing the factors' interdependency by the application of change strategies and tactics in a committed and skilful way. Conclusion Project management, as the most important and active key factor, is advised to cope with the interrelationships of the influencing factors in a gradually more fundamental way by using strategies and tactics that enable learning processes. Then small-scale shared care projects may change into a disease management network at a large scale, which may yield the future blueprint to proceed. PMID:16896415

From shared care to disease management: key-influencing factors.

PubMed

Eijkelberg, I M; Spreeuwenberg, C; Mur-Veeman, I M; Wolffenbuttel, B H

2001-01-01

In order to improve the quality of care of chronically ill patients the traditional boundaries between primary and secondary care are questioned. To demolish these boundaries so-called 'shared care' projects have been initiated in which different ways of substitution of care are applied. When these projects end, disease management may offer a solution to expand the achieved co-operation between primary and secondary care. Answering the question: What key factors influence the development and implementation of shared care projects from a management perspective and how are they linked? The theoretical framework is based on the concept of the learning organisation. Reference point is a multiple case study that finally becomes a single case study. Data are collected by means of triangulation. The studied cases concern two interrelated Dutch shared care projects for type 2 diabetic patients, that in the end proceed as one disease management project. In these cases the predominant key-influencing factors appear to be the project management, commitment and local context, respectively. The factor project management directly links the latter two, albeit managing both appear prerequisites to its success. In practice this implies managing the factors' interdependency by the application of change strategies and tactics in a committed and skillful way. Project management, as the most important and active key factor, is advised to cope with the interrelationships of the influencing factors in a gradually more fundamental way by using strategies and tactics that enable learning processes. Then small-scale shared care projects may change into a disease management network at a large scale, which may yield the future blueprint to proceed.

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. © The American Society of Tropical Medicine and Hygiene.

Gender differences in how retirees perceive factors influencing unretirement.

PubMed

Armstrong-Stassen, Marjorie; Staats, Sara

2012-01-01

Returning to paid employment after retirement is occurring in many developed countries and can be expected to increase in the future. This study compared how women (n = 202) and men (n = 347) who had retired from a managerial or professional career occupation perceived factors associated with unretirement. Retired professional women perceived reasons to unretire, age-friendly human resource practices, and re-entry barriers to have greater influence on retirees' decision to unretire than retired managerial women and retired men. Both groups of retired women perceived training and development opportunities to have more influence than retired men. A major contribution of this study is the identification of pre-retirement career occupation as having an important effect on how female, but not male, retirees perceived the various factors. The findings suggest that researchers and employers need to consider the diversity that exists among retirees, not only gender differences but also differences among retired career women.

Health related quality of life and influencing factors among welders.

PubMed

Qin, Jingxiang; Liu, Wuzhong; Zhu, Jun; Weng, Wei; Xu, Jiaming; Ai, Zisheng

2014-01-01

Occupational exposure to welding fumes is a serious occupational health problem all over the world. Welders are exposed to many occupational hazards; these hazards might cause some occupational diseases. The aim of the study was to assess the health related quality of life (HRQL) of electric welders in Shanghai China and explore influencing factors to HRQL of welders. 301 male welders (without pneumoconiosis) and 305 non-dust male workers in Shanghai were enrolled in this study. Short Form-36 (SF-36) health survey questionnaires were applied in this cross-sectional study. Socio-demographic, working and health factors were also collected. Multiple stepwise regress analysis was used to identify significant factors related to the eight dimension scores. Six dimensions including role-physical (RP), bodily pain (BP), general health (GH), validity (VT), social function (SF), and mental health (MH) were significantly worse in welders compared to non-dust workers. Multiple stepwise regress analysis results show that native place, monthly income, quantity of children, drinking, sleep time, welding type, use of personal protective equipment (PPE), great events in life, and some symptoms including dizziness, discomfort of cervical vertebra, low back pain, cough and insomnia may be influencing factors for HRQL of welders. Among these factors, only sleep time and the use of PPE were salutary. Some dimensions of HRQL of these welders have been affected. Enterprises which employ welders should take measures to protect the health of these people and improve their HRQL.

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

PubMed

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

2010-02-01

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

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.

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

Factors which influence necropsy requests: a psychological approach.

PubMed Central

Start, R. D.; Hector-Taylor, M. J.; Cotton, D. W.; Startup, M.; Parsons, M. A.; Kennedy, A.

1992-01-01

AIMS: To determine which factors influence a clinician's decision to request a necropsy. METHODS: Patient age, confidence in premortem diagnosis, relatives' attitudes, and conditions of necropsy practice were combined factorially (two levels each) in separate medical and surgical questionnaires based on clinical case histories. The interactions between the factors were measured by a repeated measures factorial analysis of variance for each of the two clinical groups. The influence of the clinician's interest in necropsies on these interactions was also examined by a similar method. RESULTS: Necropsies were more likely to be requested on young patients, when diagnostic confidence was low, and when relatives' attitudes were favourable. Conditions of necropsy practice did not affect the likelihood of a request and there was no apparent overall difference in necropsy requests between the two groups of clinicians. The "patient age" and "relatives" factors had less influence on the decision of the surgical group to request necropsy. This was attributed to the opportunity to "see for themselves" at operation and was supported by the finding that surgeons were very likely to request necropsies in the absence of surgical intervention. Clinicians from both groups with a high pre-existing interest in the necropsy were consistently more likely to request necropsies. CONCLUSIONS: The "case history" based questionnaires successfully measured the relative influence of multiple factors in relation to the decision of clinicians to request a necropsy. These findings suggest that any attempt to reverse the decline in necropsy rates should focus on changing the clinician's perception of the value of the modern necropsy. PMID:1556237

Factors influencing preparation of polyaniline doped with hydrochloric acid

NASA Astrophysics Data System (ADS)

Chuanyu, Sun; Yu, Wang

2014-12-01

Factors influencing the reaction of chemical polymerization during aniline doping with hydrochloric acid (HCl) have been studied in this work. The optimal parameters for the preparation of polyaniline were determined as follows: aniline concentration - 4 mass %, molar ratios of oxidant (NH4)2S2O8:aniline - 1.2:1 and 1.3:1, the concentration of dopant - 1 mol/L. Fourier transform infrared spectroscopy (FT-IR) was applied to characterize the structure of polyaniline.

Pakistani medical students' specialty preference and the influencing factors.

PubMed

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

2011-07-01

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

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.

Leadership styles of Finnish nurse managers and factors influencing it.

PubMed

Vesterinen, Soili; Isola, Arja; Paasivaara, Leena

2009-05-01

The purpose of the present study was to explore nurse managers' perceptions of their leadership styles and factors influencing it. It is a challenge for nurse managers to retain nurses in hospitals and to ensure a high quality of care in nursing practice. Leadership style is an important part of leadership. Knowledge concerning nurse managers' resonant and non-resonant leadership styles provides nurse managers with tools to reflect on their own leadership style. Open-ended, tape-recorded interviews were conducted with 13 nurse managers from five Finnish hospitals and two long-term care facilities. The data were analysed using qualitative content analysis. Five categories of leadership style were discerned: visionary, coaching, affiliate, democratic, commanding. Factors that influence leadership style were identified: earlier superiors, values, information, cooperation, employees and education. The results of this study show that Finnish nurse managers use both resonant and non-resonant leadership styles. The findings of this study show that nurse managers use a variety of leadership styles. The study demonstrates the importance of knowledge about leadership styles and factors influencing it among nurse managers providing future leadership and management education.

Factors influencing elderly women's mammography screening decisions: implications for counseling.

PubMed

Schonberg, Mara A; McCarthy, Ellen P; York, Meghan; Davis, Roger B; Marcantonio, Edward R

2007-11-16

Although guidelines recommend that clinicians consider life expectancy before screening older women for breast cancer, many older women with limited life expectancies are screened. We aimed to identify factors important to mammography screening decisions among women aged 80 and older compared to women aged 65-79. Telephone surveys of 107 women aged 80+ and 93 women aged 65-79 randomly selected from one academic primary care practice who were able to communicate in English (60% response rate). The survey addressed the following factors in regards to older women's mammography screening decisions: perceived importance of a history of breast disease, family history of breast cancer, doctor's recommendations, habit, reassurance, previous experience, mailed reminder cards, family/friend's recommendations or experience with breast cancer, age, health, and media. The survey also assessed older women's preferred role in decision making around mammography screening. Of the 200 women, 65.5% were non-Hispanic white and 82.8% were in good to excellent health. Most (81.3%) had undergone mammography in the past 2 years. Regardless of age, older women ranked doctor's recommendations as the most important factor influencing their decision to get screened. Habit and reassurance were the next two highly ranked factors influencing older women to get screened. Among women who did not get screened, women aged 80 and older ranked age and doctor's counseling as the most influential factors and women aged 65-79 ranked a previous negative experience with mammography as the most important factor. There were no significant differences in preferred role in decision-making around mammography screening by age, however, most women in both age groups preferred to make the final decision on their own (46.6% of women aged 80+ and 50.5% of women aged 65-79). While a doctor's recommendation is the most important factor influencing elderly women's mammography screening decisions, habit and reassurance

Factors influencing worker use of personal protective eyewear.

PubMed

Lombardi, David A; Verma, Santosh K; Brennan, Melanye J; Perry, Melissa J

2009-07-01

To identify and describe the array of factors that influence a workers' decision to wear personal protective eyewear (PPE) and the barriers that exist in preventing their use. A series of focus groups enrolled workers and supervisors primarily from manufacturing, construction, or service/retail industries that had potential exposure to eye injury hazards in their job tasks. Focus group sessions were facilitated to collect qualitative and quantitative data in two categories, "sought information" and "emergent themes", related to the factors influencing use of PPE. We conducted a series of 7 groups with 51 participants, 36 (71%) males and 15 (29%) females ranging in age from 19 to 64 years old, from a variety of occupations including construction (24%), production (22%), installation, repair and maintenance (14%), and healthcare (10%). Most were highly experienced in their occupation (>10 years); males (86%) and females (53%), and had received some safety training in the past (82%). The majority of workers in this study were required to wear PPE on their worksite (78%), however only 55% had a dedicated safety officer. A conceptual model that summarizes the "sought information" and "emergent themes" is presented that depicts the decision making process for the factors influencing use of PPE and consists of three primary branches; perceptions of hazards and risks, "barriers" to PPE usage, and enforcement and reinforcement. Lack of comfort/fit, and fogging and scratching of the eyewear were suggested as the most important barriers to PPE usage. Younger age and lack of safety training were other important factors affecting use of PPE. Several potentially modifiable factors identified would lead to an increase in workers' PPE use and encourage supervisors to provide ongoing positive feedback on the continuous use of PPE by workers at risk for an eye injury.

Genetic and pharmacological factors that influence reproductive aging in nematodes.

PubMed

Hughes, Stacie E; Evason, Kimberley; Xiong, Chengjie; Kornfeld, Kerry

2007-02-16

Age-related degenerative changes in the reproductive system are an important aspect of aging, because reproductive success is the major determinant of evolutionary fitness. Caenorhabditis elegans is a prominent organism for studies of somatic aging, since many factors that extend adult lifespan have been identified. However, mechanisms that control reproductive aging in nematodes or other animals are not well characterized. To use C. elegans to measure reproductive aging, we analyzed mated hermaphrodites that do not become sperm depleted and monitored the duration and level of progeny production. Mated hermaphrodites display a decline of progeny production that culminates in reproductive cessation before the end of the lifespan, demonstrating that hermaphrodites undergo reproductive aging. To identify factors that influence reproductive aging, we analyzed genetic, environmental, and pharmacological factors that extend lifespan. Dietary restriction and reduced insulin/insulin-like growth factor signaling delayed reproductive aging, indicating that nutritional status and a signaling pathway that responds to environmental stress influence reproductive aging. Cold temperature delayed reproductive aging. The anticonvulsant medicine ethosuximide, which affects neural activity, delayed reproductive aging, indicating that neural activity can influence reproductive aging. Some of these factors decrease early progeny production, but there is no consistent relationship between early progeny production and reproductive aging in strains with an extended lifespan. To directly examine the effects of early progeny production on reproductive aging, we used sperm availability to modulate the level of early reproduction. Early progeny production neither accelerated nor delayed reproductive aging, indicating that reproductive aging is not controlled by use-dependent mechanisms. The implications of these findings for evolutionary theories of aging are discussed.

Factors Potentially Influencing Student Acceptance of Biological Evolution

NASA Astrophysics Data System (ADS)

Wiles, Jason R.

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

Factors influencing food choice of athletes at international competition events.

PubMed

Pelly, Fiona E; Burkhart, Sarah J; Dunn, Peter

2018-02-01

Although the nutrient requirements and dietary intake of athletes have been thoroughly investigated, little is known about the influences on their food choice, particularly prior to and during competition. This study sought to investigate factors that influence food selection of athletes at two similar international competition events: the Melbourne 2006 and Delhi 2010 Commonwealth Games. A secondary aim was to explore differences in these factors between at each event given the culturally diverse locations. A survey developed for this study was distributed to athletes in the village dining hall at both events. Athletes scored a selection of factors influencing food choice on a scale of 1 (not important) to 5 (very important). A total of 769 individuals completed the questionnaire in total, with 351 (46%) from Delhi and 418 (54%) from Melbourne. Overall, athletes rated nutrient composition (M = 4.22), stage of competition (M = 4.09), time of day (M = 4.02) and familiarity of the food (M = 4.07) higher than sensory properties (smell M = 3.88; visual appearance M = 3.22) when making a food selection. Visual appearance (p = 0.01), stage of competition (p < 0.001) and time of day (p = 0.01) had greater influence in Delhi than Melbourne. Overall, a significantly higher proportion of female athletes rated smell (p < 0.001) and familiar food (p < 0.001) as important compared to males. The stage of competition and nutrition composition was rated as very important by the greatest proportion of athletes from weight category sports (61.9%) and endurance sports (57.9%) respectively. The influence of the coach and team mates was less of an influence than other factors, but more so for athletes from Non-Western regions. Further investigation of the various determinants and motives for food section of athletes from a range of sports and cultures is warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Personal and situational factors influencing coaches' perceptions of stress.

PubMed

Knight, Camilla J; Reade, Ian L; Selzler, Anne-Marie; Rodgers, Wendy M

2013-01-01

Coaching has been recognised as a demanding occupation, associated with a range of stressors. The extent to which coaches perceive stress is likely to be influenced by various personal and situational factors. The purpose of this study was to identify coaches' levels of perceived stress and examine the personal and situational factors that may influence coaches' perceptions of stress. In total, 502 coaches working with university, college, Canada Games, and/or nationally identified athletes completed this study. Coaches completed an online survey, which included questions regarding demographics, work/job-related considerations, and aspects relating to their contract. Coaches also completed the Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1983). Overall coaches indicated slightly below average levels of perceived stress (M = 15.13 out of 40) compared with norm-values (Cohen & Janicki-Deverts, 2012). Demographic factors, job-related characteristics, and certain aspects of their contract were associated with coaches' perceptions of stress. In particular, unclear expectations, long-working hours (>40), lack of agreed evaluation criteria, higher salaries, and a lack of social support were related to higher perceptions of stress. As such, the findings of the current study indicate that a reduction in perceived stress is likely to be achieved through a multifaceted approach that addresses multiple factors associated with coaching.

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'. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

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

Factors influencing palliative care. Qualitative study of family physicians' practices.

PubMed Central

Brown, J. B.; Sangster, M.; Swift, J.

1998-01-01

OBJECTIVE: To examine factors that influence family physicians' decisions to practise palliative care. DESIGN: Qualitative method of in-depth interviews. SETTING: Southwestern Ontario. PARTICIPANTS: Family physicians who practise palliative care on a full-time basis, who practise on a part-time basis, or who have retired from active involvement in palliative care. METHOD: Eleven in-depth interviews were conducted to explore factors that influence family physicians' decisions to practise palliative care and factors that sustain their interest in palliative care. All interviews were audiotaped and transcribed verbatim. The analysis strategy used a phenomenological approach and occurred concurrently rather than sequentially. All interview transcriptions were read independently by the researchers, who then compared and combined their analyses. Final analysis involved examining all interviews collectively, thus permitting relationships between and among central themes to emerge. MAIN OUTCOME FINDINGS: The overriding theme was a common philosophy of palliative care focusing on acceptance of death, whole person care, compassion, communication, and teamwork. Participants' philosophies were shaped by their education and by professional and personal experiences. In addition, participants articulated personal and systemic factors currently affecting their practice of palliative care. CONCLUSIONS: Participants observed that primary care physicians should be responsible for their patients' palliative care within the context of interdisciplinary teams. For medical students to be knowledgeable and sensitive to the needs of dying patients, palliative care should be given higher priority in the curriculum. Finally, participants argued compellingly for transferring the philosophy of palliative care to the overall practice of medicine. PMID:9612588

Factors Influencing Professional Help-Seeking for Suicidality.

PubMed

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

2018-05-01

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

Influencing factors on the visibility of surface distresses

NASA Astrophysics Data System (ADS)

Smęt, Wojciech; Skakuj, Marek

2018-05-01

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

Factors influencing the pathways in response to complaints.

PubMed

Hsieh, Sophie Yahui

2010-01-01

The purpose of this paper is to explore hospital staff response to patient complaints and the factors influencing the response pathway. The paper uses an exploratory study in a large Taiwanese hospital purposefully chosen as a case study site. The critical incident technique (CIT) is implemented, using a questionnaire along with non-participant observations in which the results have been triangulated. A total of 59 cases were collected. The study found when facing "humaneness" complaints, hospital staff attempted to investigate the event and then explain the facts to the complainant or empathise with him/her and then refer the problem to the relevant unit. In response to complaints combining "communication" and "care/treatment and humaneness", staff tended to investigate the event's details and then directly explain them to the complainant. When complaints involved "care/treatment", staff tended to empathise with the complainant, investigate the facts and explain them to the complainant. Additionally, the organisational response to complaints was influenced by who made complaints; its type, severity, complaining method and patient status. The literature revealed that the case study is the most common organisational study method. However, this approach is criticised for not offering findings that can be generalised. Complaint nature is the major factor influencing the response pathway. If healthcare managers intend to reduce complaint rates then they need to carefully classify the complaint's nature. Different complaints have different handling procedures and guidelines to help managers resolve complaints in the first place. There are extensive studies focusing on investigating complaints and their resolution. These studies tend not to demonstrate various means of handling patient complaints. Neither do they describe how different complaints might lead to different outcomes. Therefore, this paper explores hospital staff response to patient complaints and the factors

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

A review on factors influencing bioaccessibility and bioefficacy of carotenoids.

PubMed

Priyadarshani, A M B

2017-05-24

Vitamin A deficiency is one of the most prevalent deficiency disorders in the world. As shown by many studies plant food based approaches have a real potential on prevention of vitamin A deficiency in a sustainable way. Carotenoids are important as precursors of vitamin A as well as for prevention of cancers, coronary heart diseases, age-related macular degeneration, cataract etc. Bioaccessibility and bioefficacy of carotenoids are known to be influenced by numerous factors including dietary factors such as fat, fiber, dosage of carotenoid, location of carotenoid in the plant tissue, heat treatment, particle size of food, carotenoid species, interactions among carotenoids, isomeric form and molecular linkage and subject characteristics. Therefore even when carotenoids are found in high quantities in plant foods their utilization may be unsatisfactory because some factors are known to interfere as negative effectors.

[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.

Factors Influencing Right Hemisphere Engagement During Metaphor Comprehension

PubMed Central

Diaz, Michele T.; Eppes, Anna

2018-01-01

Although the left hemisphere is critical for language, clinical, behavioral, and neuroimaging research suggest that the right hemisphere also contributes to language comprehension. In particular, research has suggested that figurative language may be one type of language that preferentially engages right hemisphere regions. However, there is disagreement about whether these regions within the right hemisphere are sensitive to figurative language per se or to other factors that co-vary with figurativeness. In this article, we will review the neuroimaging literature on figurative language processing, focusing on metaphors, within the context of several theoretical perspectives that have been proposed about hemispheric function in language. Then we will examine three factors that may influence right hemisphere engagement: novelty, task difficulty, and context. We propose that factors that increase integration demands drive right hemisphere involvement in language processing, and that such recruitment is not limited to figurative language. PMID:29643825

Environmental influences: factors influencing a woman's decision to use dietary supplements.

PubMed

Conner, Mark; Kirk, Sara F L; Cade, Janet E; Barrett, Jennifer H

2003-06-01

Use of dietary supplements by women, particularly those over 40 years of age may be widespread in the United Kingdom. However, from surveillance data, there appears to be a disparity between nutrition and health needs and the rationale for and actual use of dietary supplements by women. This apparent paradox forms the basis for an inverse supplement hypothesis (i.e., supplement use in women appears to be most prevalent among those with least need). Little research has been done to examine the factors underlying the decision to use dietary supplements. Reasons for consuming dietary supplements are often complex, combining social, psychological, knowledge and economic factors. The theory of planned behavior is a widely used model for assessing factors influencing behavioral motivation and action that may be useful for assessing specific diet- and nutrition-related practices. It provided the basis for the development of a questionnaire to explore overall dietary supplement use in a cohort of women in the United Kingdom. The analysis of factors related to beliefs underlying dietary supplement use revealed differences between supplement users and nonusers. Differences included a stronger belief by users than nonusers that taking dietary supplements ensures against possible ill health. Both users and nonusers of supplements also perceived the media (books and magazines) to be a powerful influence on a person's decision to use supplements. These findings highlight the potential of the theory of planned behavior in exploring supplement-taking behavior while throwing light on the factors influencing an individual's motivations to use dietary supplements.