Predicted impact of barriers to migration on the Serengeti wildebeest population.

Directory of Open Access Journals (Sweden)

Ricardo M Holdo

Full Text Available The Serengeti wildebeest migration is a rare and spectacular example of a once-common biological phenomenon. A proposed road project threatens to bisect the Serengeti ecosystem and its integrity. The precautionary principle dictates that we consider the possible consequences of a road completely disrupting the migration. We used an existing spatially-explicit simulation model of wildebeest movement and population dynamics to explore how placing a barrier to migration across the proposed route (thus creating two disjoint but mobile subpopulations might affect the long-term size of the wildebeest population. Our simulation results suggest that a barrier to migration--even without causing habitat loss--could cause the wildebeest population to decline by about a third. The driver of this decline is the effect of habitat fragmentation (even without habitat loss on the ability of wildebeest to effectively track temporal shifts in high-quality forage resources across the landscape. Given the important role of the wildebeest migration for a number of key ecological processes, these findings have potentially important ramifications for ecosystem biodiversity, structure, and function in the Serengeti.

Effects of passage barriers on demographics and stability properties of a virtual trout populations

Science.gov (United States)

Bret Harvey; Steven Railsback

2011-01-01

Habitat fragmentation is widely assumed to have negative effects on populations and communities, but some effects of fragmentation are subtle, difficult to measure and not always negative. For stream fish, barriers to upstream passage, such as waterfalls or culverts with perched outlets, are a common cause of fragmentation. We explored the effects of barriers on a...

Storm impacts on small barrier islands

DEFF Research Database (Denmark)

Kroon, Aart; Fruergaard, Mikkel

The shorelines of the Baltic Sea and the inner coastal waters in Denmark consist of many barrier islands. These sandy barrier islands were mainly formed in the Holocene and are still very dynamic. The present day changes in the morphology are dominantly governed by storm waves and associated high...

Exploring drivers and barriers to sustainability green business practices within small medium sized enterprises: primary findings

Directory of Open Access Journals (Sweden)

Amir Aghelie

2017-03-01

Full Text Available Presently the conducted studies on how SMEs should integrate sustainability align with their core business principle is limited. Most of the discussion on this field is emphasized to address issues for larger organizations and very limited effort on small firms. The drivers and barriers of approaching sustainability practices in SMEs are different from those in large organizations since SMEs lack technical specialist, experience and money required to make such strategy. Since SMEs play a significant role in nation’s economic growth, it is essential to study and find their drivers and barriers toward sustainability business practices constitutes main motivation of this paper. This is a primary finding that aims to understand the SME motivation and barriers that are facing in implementing green sustainable business practices to offer insight look to small firms to find key factors that influence adoption of sustainability business approach within their management practices.

Pathways for Small Molecule Delivery to the Central Nervous System Across the Blood-Brain Barrier

OpenAIRE

Mikitsh, John L; Chacko, Ann-Marie

2014-01-01

The treatment of central nervous system (CNS) disease has long been difficult due to the ineffectiveness of drug delivery across the blood-brain barrier (BBB). This review summarizes important concepts of the BBB in normal versus pathophysiology and how this physical, enzymatic, and efflux barrier provides necessary protection to the CNS during drug delivery, and consequently treatment challenging. Small molecules account for the vast majority of available CNS drugs primarily due to their abi...

Genetic diversity and population differentiation of small giant clam Tridacna maxima in Comoros islands assessed by microsatellite markers.

Science.gov (United States)

Ahmed Mohamed, Nadjim; Yu, Qian; Chanfi, Mohamed Ibrahim; Li, Yangping; Wang, Shi; Huang, Xiaoting; Bao, Zhenmin

2016-01-01

Small giant clam, Tridacna maxima , widely distributed from French Polynesia to East Africa, has faced population declines due to over-exploitation. Comoros islands are an important biogeographic region due to potential richness of marine species, but no relevant information is available. In order to facilitate devising effective conservation management plan for T. maxima , nine microsatellite markers were used to survey genetic diversity and population differentiation of 72 specimens collected from three Comoros islands, Grande Comore, Moheli and Anjouan. A total of 51 alleles were detected ranged from 2 to 8 per locus. Observed and expected heterozygosity varied from 0.260 to 0.790 and from 0.542 to 0.830, respectively. All populations have high genetic diversity, especially the population in Moheli, a protected area, has higher genetic diversity than the others. Significant heterozygote deficiencies were recorded, and null alleles were probably the main factor leading to these deficits. F ST value indicated medium genetic differentiation among the populations. Although significant, AMOVA revealed 48.9 % of genetic variation within individuals and only a small variation of 8.9 % was found between populations. Gene flow was high ( Nm  = 12.40) between Grande Comore and Moheli, while lower ( Nm  = 1.80) between Grande Comore and Anjouan, explaining geographic barriers to genetic exchanges might exist in these two islands. Global gene flow analysis ( Nm  = 5.50) showed that larval dispersal is enough to move between the islands. The high genetic diversity and medium population differentiation revealed in the present study offer useful information on genetic conservation of small giant clams.

Perception of barriers to physical exercise in women population over 60

Directory of Open Access Journals (Sweden)

Jéssica Bianca Aily

2017-06-01

Full Text Available Abstract Aims This study evaluated the possible barriers to the permanence of physical exercise (PE of old women. Methods The study population comprised 61 old women participants for at least one year of a supervised PE program, who underwent anamnesis, and applied the Barriers Questionnaire to Physical Activity Practice in the Elderly (QBPAFI. Exploratory factorial analysis was used to evaluate QBPAFI data. The analysis of principal component was applied to the 22 questions through orthogonal rotation to analyze the correlation between the questions. The Kaiser-Meyer-Olkin test was applied to evaluate the suitability of the sample size, and the Bartlett's test to assess whether the original matrix correlation is an identity matrix. Eigenvalues greater than 1 were considered for analysis. Results The motivational factor was the major determinant of perceived barriers (43.3%, followed by psychosocial (12.29%, facilities and appearance (8.75%, and exercise conditions (8.10% factors. Conclusion Knowing the benefits of physical activity, and the main barriers that prevent the permanence of active old people to physical exercise programs, new strategies must be taken to increase the rate of adherence of this group.

An innovative program to address learning barriers in small schools: Washington State School Nurse Corps.

Science.gov (United States)

Fast, Gail Ann; Gray, Lorali; Miles-Koehler, Mona

2013-01-01

While all schools in Washington State have had to deal with shrinking financial resources, small, rural school districts, with fewer than 2,000 students, face unique circumstances that further challenge their ability to meet rising student health needs. This article will explore how small districts utilize the services of the Washington State School Nurse Corps (SNC), an innovative program that supports student health and safety while reducing barriers to learning. Through direct registered nursing services and regional nurse administrative consultation and technical assistance, the SNC strengthens rural school districts' capacity to provide a safe and healthy learning environment. In addition, we will examine current research that links health and learning to discover how the SNC model is successful in addressing health risks as barriers to learning. Lastly, as resources continue to dwindle, partnerships between schools, the SNC, and state and local health and education organizations will be critical in maintaining health services and learning support to small, rural schools.

Barriers to Physical Activity in a Mass Transit Population: A Qualitative Study.

Science.gov (United States)

Das, Bhibha M; Petruzzello, Steven J

2016-01-01

The physical inactivity epidemic continues be one of the greatest public health challenges in contemporary society in the United States. The transportation industry is at greater risk of physical inactivity, compared with individuals in other sectors of the workforce. The aim of this study was to use the Nominal Group Technique, a focus group technique, to examine mass transit employees' perceptions of the barriers to physical activity at their worksite. Three focus groups (n = 31) were conducted to examine mass transit employees' perceptions of barriers to physical activity at the worksite. Salient barriers included (1) changing work schedules, (2) poor weather conditions, and (3) lack of scheduled and timely breaks. Findings were consistent with previous research demonstrating shift work, poor weather, and lack of breaks can negatively impact mass transit employees' ability to be physically active. Although physical activity barriers for this population have been consistent for the last 20 years, public health practice and policy have not changed to address these barriers. Future studies should include conducing focus groups stratified by job classification (eg, operators, maintenance, and clerical) along with implementing and evaluating worksite-based physical activity interventions and policy changes.

Oculocutaneous albinism: identifying and overcoming barriers to vision care in a Nigerian population.

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Udeh, N N; Eze, B I; Onwubiko, S N; Arinze, O C; Onwasigwe, E N; Umeh, R E

2014-06-01

To assess eye care service utilization, and identify access barriers in a south-eastern Nigerian albino population. The study was a population-based, cross-sectional survey conducted in Enugu state between August, 2011 and January, 2012. Using the data base of the state's Albino Foundation and tailored awareness creation, persons living with albinism were identified and recruited at two study centres. Data on participants' socio-demographics, perception of vision, visual needs, previous eye examination and or low vision assessment, use of glasses or low vision devices were collected. Reasons for non-utilisation of available vision care services were also obtained. Descriptive and comparative statistics were performed. A p low vision assessment and none--0.0% had used low vision device. Of the participants, 82.4% reported previous eye examination, 33.3% had not used spectacles previously, despite the existing need. Ignorance--88.9% and poor access--8.5% were the main barriers to uptake of vision care services. In Enugu, Nigeria, there is poor awareness and low utilization of vision care services among people with albinism. The identified barriers to vision care access are amenable to awareness creation and logistic change in the provision of appropriate vision care services.

Employees' Perceptions of Barriers to Participation in Training and Development in Small Engineering Businesses

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Susomrith, Pattanee; Coetzer, Alan

2015-01-01

Purpose: This paper aims to investigate barriers to employee participation in voluntary formal training and development opportunities from the perspective of employees in small engineering businesses. Design/methodology/approach: An exploratory qualitative methodology involving data collection via site visits and in-depth semi-structured…

Separated by sand, fused by dropping water: habitat barriers and fluctuating water levels steer the evolution of rock-dwelling cichlid populations in Lake Tanganyika.

Science.gov (United States)

Koblmüller, Stephan; Salzburger, Walter; Obermüller, Beate; Eigner, Eva; Sturmbauer, Christian; Sefc, Kristina M

2011-06-01

The conditions of phenotypic and genetic population differentiation allow inferences about the evolution, preservation and loss of biological diversity. In Lake Tanganyika, water level fluctuations are assumed to have had a major impact on the evolution of stenotopic littoral species, though this hypothesis has not been specifically examined so far. The present study investigates whether subtly differentiated colour patterns of adjacent Tropheus moorii populations are maintained in isolation or in the face of continuous gene flow, and whether the presumed influence of water level fluctuations on lacustrine cichlids can be demonstrated in the small-scale population structure of the strictly stenotopic, littoral Tropheus. Distinct population differentiation was found even across short geographic distances and minor habitat barriers. Population splitting chronology and demographic histories comply with our expectation of old and rather stable populations on steeper sloping shore, and more recently established populations in a shallower region. Moreover, population expansions seem to coincide with lake level rises in the wake of Late Pleistocene megadroughts ~100 KYA. The imprint of hydrologic events on current population structure in the absence of ongoing gene flow suggests that phenotypic differentiation among proximate Tropheus populations evolves and persists in genetic isolation. Sporadic gene flow is effected by lake level fluctuations following climate changes and controlled by the persistence of habitat barriers during lake level changes. Since similar demographic patterns were previously reported for Lake Malawi cichlids, our data furthermore strengthen the hypothesis that major climatic events synchronized facets of cichlid evolution across the East African Great Lakes. © 2011 Blackwell Publishing Ltd.

Tocantins river as an effective barrier to gene flow in Saguinus niger populations

Directory of Open Access Journals (Sweden)

Marcelo Vallinoto

2006-01-01

Full Text Available The Saguinus represent the basal genus of the Callitrichinae subfamily. Traditionally this genus is divided into three groups: Hairy, Mottled and Bare-face, however, molecular data failed to validate these groups as monophyletic units, as well as raised some subspecies to the species status. This is the case of the former subspecies Saguinus midas midas and S. midas niger, which are now considered as different species. In the present study, we sequenced a portion of the D-loop mtDNA region in populations from the East bank of the Xingu and from both banks of the Tocantins river, in order to test the effectiveness of large rivers as barriers to the gene flow in Saguinus. According to our results, the populations from the East and West banks of the Tocantins river are more divergent than true species like S. mystax and S. imperator. The Tocantins river may be acting as a barrier to gene flow, and consequently these very divergent populations may represent distinct taxonomic entities (species?.

75 FR 9431 - Small and Medium-Sized Enterprises: U.S. and EU Export Activities, and Barriers and Opportunities...

Science.gov (United States)

2010-03-02

... to the USTR on the first investigation, No. 332-508, Small and Medium-Sized Enterprises: Overview of..., investigation No. 332-509, Small and Medium-Sized Enterprises: U.S. and EU Export Activities, and Barriers and Opportunities Experienced by U.S. Firms, and investigation No. 332- 510, Small and Medium-Sized Enterprises...

Mucosal pathobiology and molecular signature of epithelial barrier dysfunction in the small intestine in irritable bowel syndrome.

Science.gov (United States)

González-Castro, Ana M; Martínez, Cristina; Salvo-Romero, Eloísa; Fortea, Marina; Pardo-Camacho, Cristina; Pérez-Berezo, Teresa; Alonso-Cotoner, Carmen; Santos, Javier; Vicario, María

2017-01-01

Irritable bowel syndrome (IBS) is one of the most prevalent gastrointestinal disorders in developed countries. Its etiology remains unknown; however, a common finding, regardless of IBS subtype, is the presence of altered intestinal barrier. In fact, signaling and location of cell-to-cell adhesion proteins, in connection with increased immune activity, seem abnormal in the intestinal epithelium of IBS patients. Despite that most research is performed on distal segments of the intestine, altered permeability has been reported in both, the small and the large bowel of all IBS subtypes. The small intestine carries out digestion and nutrient absorption and is also the site where the majority of immune responses to luminal antigens takes place. In fact, the upper intestine is more exposed to environmental antigens than the colon and is also a site of symptom generation. Recent studies have revealed small intestinal structural alterations of the epithelial barrier and mucosal immune activation in association with intestinal dysfunction, suggesting the commitment of the intestine as a whole in the pathogenesis of IBS. This review summarizes the most recent findings on mucosal barrier alterations and its relationship to symptoms arising from the small intestine in IBS, including epithelial structural abnormalities, mucosal immune activation, and microbial dysbiosis, further supporting the hypothesis of an organic origin of IBS. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

Working with What We've Got: Perceptions of Barriers and Supports among Small-Metropolitan-Area Same-Sex Adopting Couples

Science.gov (United States)

Kinkler, Lori A.; Goldberg, Abbie E.

2011-01-01

In seeking to adopt, lesbians and gay men may confront various barriers and obstacles. Ideally, they have access to a variety of support resources that can help to buffer the negative effects of these barriers. Lesbians and gay men living in small metropolitan communities may have limited access to support resources, however. The current…

Barriers to energy efficiency in small industry clusters: Multi-criteria-based prioritization using the analytic hierarchy process

International Nuclear Information System (INIS)

Nagesha, N.; Balachandra, P.

2006-01-01

The small scale industry (SSI) is an important component of Indian economy and a majority of SSI units tend to exist in geographical clusters. Energy efficiency is crucial for the survival and growth of energy intensive SSI clusters, not only to improve their competitiveness through cost reduction but also to minimize adverse environmental impacts. However, this is easier said than done due to the presence of a variety of barriers. The identification of relevant barriers and their appropriate prioritization in such clusters is a prerequisite to effectively tackle them. This paper identifies relevant barriers to energy efficiency and their dimensions in SSI clusters. Further, the barriers are prioritized based on the perceptions and experiences of entrepreneurs, the main stakeholders of SSIs, using the analytic hierarchy process (AHP). The field data from two energy intensive clusters of foundry and brick and tile in Karnataka (a state in India) reveal that the prioritization remained the same despite differences in the relative weights of barrier groups. The financial and economic barrier (FEB) and behavioural and personal barrier (BPB) have emerged as the top two impediments to energy efficiency improvements

Levels of Engagement and Barriers to Physical Activity in a Population of Adults with Learning Disabilities

Science.gov (United States)

Hawkins, Andrew; Look, Roger

2006-01-01

This study examined levels of, and barriers to, physical activity in a population of 19 adults with learning disabilities living in community supported accommodation, using diary records and semi-structured interviews with staff. The levels of physical activity were higher in the sample population than previous figures for adults with learning…

Engaging the small commercial sector: new approaches for solving market barriers

International Nuclear Information System (INIS)

Dandridge, Cyane; Walton, Jennifer; Bertoldi, Paolo

2005-01-01

This paper examines how effectively working with students and contractors can engage small commercial businesses in energy efficiency measures. Small commercial businesses are an underserved and hard-to-reach market for energy efficiency services. Yet, this sector comprises a significant percentage of all businesses and aggregate energy usage. Two main barriers to doing an energy retrofit in small businesses include getting the business to agree to participate and getting them to implement suggested measures. Student outreach addresses the first, and using a mechanical or electrical contractor as an ESCO is a great way to address the second. The Awareness for Community Energy (ACE) Program is currently being offered throughout the United States. ACE employs high school and college students as interns and trains them in small business energy auditing. The business more readily accepts the marketing of energy services by a student, since it is seen as an opportunity to contribute to a student's educational experience. In one case, ACE program participants audited over 150 small businesses in a three-month period. Electrical and mechanical contractors are prime candidates to both disseminate information on energy efficiency and carry out the necessary retrofits. The owners of most energy using facilities already have trusted mechanical/electrical service contractors. By diffusing ESCO concepts amongst existing service contractors, there is a far greater chance of upgrading the energy efficiency throughout the small business sector. Such diffusion activities will involve training and awareness programs for contractors, as well as encouragement of financial institutions to develop supportive financing products

Diversity of human small intestinal Streptococcus and Veillonella populations

NARCIS (Netherlands)

van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J.; Zoetendal, Erwin G.; Kleerebezem, Michiel

Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed

Show small close comfort and listen - How to overcome barriers in the use of social media

NARCIS (Netherlands)

Verjans, Steven

2011-01-01

Verjans, S. (2011, 23 November). Show small close comfort and listen - How to overcome barriers in the use of social media. Presentation at the SVEA Final Conference "Next Generation Learning - How to Integrate Social Media in Vocational and Adult Training", Brussels, Belgium.

A sea water barrier to coral gene flow.

Science.gov (United States)

Lessios, H A

2012-11-01

Land is not the only barrier to dispersal encountered by marine organisms. For sedentary shallow water species, there is an additional, marine barrier, 5000 km of uninterrupted deep-water stretch between the central and the eastern Pacific. This expanse of water, known as the ‘Eastern Pacific Barrier’, has been separating faunas of the two oceanic regions since the beginning of the Cenozoic. Species with larvae that cannot stay in the plankton for the time it takes to cross between the two sides have been evolving independently. That the eastern Pacific does not share species with the rest of the Pacific was obvious to naturalists two centuries ago (Darwin 1860). Yet, this rule has exceptions. A small minority of species are known to straddle the Eastern Pacific Barrier. One such exception is the scleractinian coral Porites lobata (Fig. 1). This species is spread widely throughout the Indo-Pacific, where it is one of the major reef-builders, but it is also encountered in the eastern Pacific. Are eastern and central Pacific populations of this coral connected by gene flow? In this issue of Molecular Ecology, Baums et al. (2012) use microsatellite data to answer this question. They show that P. lobata populations in the eastern Pacific are cut off from genetic influx from the rest of the Pacific. Populations within each of the two oceanic regions are genetically connected (though those in the Hawaiian islands are also isolated). Significantly, the population in the Clipperton Atoll, the westernmost island in the eastern Pacific, genetically groups with populations from the central Pacific, suggesting that crossing the Eastern Pacific Barrier by P. lobata propagules does occasionally occur.

Geographically weighted regression as a generalized Wombling to detect barriers to gene flow.

Science.gov (United States)

Diniz-Filho, José Alexandre Felizola; Soares, Thannya Nascimento; de Campos Telles, Mariana Pires

2016-08-01

Barriers to gene flow play an important role in structuring populations, especially in human-modified landscapes, and several methods have been proposed to detect such barriers. However, most applications of these methods require a relative large number of individuals or populations distributed in space, connected by vertices from Delaunay or Gabriel networks. Here we show, using both simulated and empirical data, a new application of geographically weighted regression (GWR) to detect such barriers, modeling the genetic variation as a "local" linear function of geographic coordinates (latitude and longitude). In the GWR, standard regression statistics, such as R(2) and slopes, are estimated for each sampling unit and thus are mapped. Peaks in these local statistics are then expected close to the barriers if genetic discontinuities exist, capturing a higher rate of population differentiation among neighboring populations. Isolation-by-Distance simulations on a longitudinally warped lattice revealed that higher local slopes from GWR coincide with the barrier detected with Monmonier algorithm. Even with a relatively small effect of the barrier, the power of local GWR in detecting the east-west barriers was higher than 95 %. We also analyzed empirical data of genetic differentiation among tree populations of Dipteryx alata and Eugenia dysenterica Brazilian Cerrado. GWR was applied to the principal coordinate of the pairwise FST matrix based on microsatellite loci. In both simulated and empirical data, the GWR results were consistent with discontinuities detected by Monmonier algorithm, as well as with previous explanations for the spatial patterns of genetic differentiation for the two species. Our analyses reveal how this new application of GWR can viewed as a generalized Wombling in a continuous space and be a useful approach to detect barriers and discontinuities to gene flow.

Real-time estimation of small-area populations with human biomarkers in sewage

International Nuclear Information System (INIS)

Daughton, Christian G.

2012-01-01

A new approach is conceptualized for measuring small-area human populations by using biomarkers in sewage. The basis for the concept (SCIM: Sewage Chemical-Information Mining) is supported by a comprehensive examination and synthesis of data published across several disciplines, including medicine, microbiology, clinical chemistry, and environmental science. Accurate measures of human populations are fundamental to numerous disciplines, including economics, marketing, politics, sociology, public health and safety (e.g., disease management; assessment of natural hazards; disaster prevention and response), quality of life, and the environment. Knowing the size, distribution, and flow of a small-area (local) population facilitates understanding the numerous and complex linkages and interactions between humans and the environment. Examples include material-flow (substance-flow) analysis, determining the magnitude of per capita contribution of pollutant loadings to watersheds, or forecasting future impacts of local populations on the environment or a population's demands on resources. While no definitive approach exists for measuring small-area populations, census-taking is a long-established convention. No approach exists, however, for gauging small-area populations in real-time, as none is able to capture population dynamics, which involve transient changes (e.g., daily influx and efflux) and lasting changes (e.g., births, deaths, change in residence). Accurate measurement of small-area populations in real time has never been possible but is essential for facilitating the design of more sustainable communities. Real-time measurement would provide communities the capability of testing what-if scenarios in design and policy decisions. After evaluation of a range of biomarkers (including the nitrogenous waste product creatinine, which has been long used in clinical chemistry as a parameter to normalize the concentrations of other urinary excretion products to account for

The waterfall paradox: How knickpoints disconnect hillslope and channel processes, isolating salmonid populations in ideal habitats

Science.gov (United States)

May, Christine; Roering, Joshua J.; Snow, Kyle; Griswold, Kitty; Gresswell, Robert E.

2017-01-01

Waterfalls create barriers to fish migration, yet hundreds of isolated salmonid populations exist above barriers and have persisted for thousands of years in steep mountainous terrain. Ecological theory indicates that small isolated populations in disturbance-prone landscapes are at greatest risk of extirpation because immigration and recolonization are not possible. On the contrary, many above-barrier populations are currently thriving while their downstream counterparts are dwindling. This quandary led us to explore geomorphic knickpoints as a mechanism for disconnecting hillslope and channel processes by limiting channel incision and decreasing the pace of base-level lowering. Using LiDAR from the Oregon Coast Range, we found gentler channel gradients, wider valleys, lower gradient hillslopes, and less shallow landslide potential in an above-barrier catchment compared to a neighboring catchment devoid of persistent knickpoints. Based on this unique geomorphic template, above-barrier channel networks are less prone to debris flows and other episodic sediment fluxes. These above-barrier catchments also have greater resiliency to flooding, owing to wider valleys with greater floodplain connectivity. Habitat preference models further indicate that salmonid habitat is present in greater quantity and quality in these above-barrier networks. Therefore the paradox of the persistence of small isolated fish populations may be facilitated by a geomorphic mechanism that both limits their connectivity to larger fish populations yet dampens the effect of disturbance by decreasing connections between hillslope and channel processes above geomorphic knickpoints.

Directions for new developments on statistical design and analysis of small population group trials.

Science.gov (United States)

Hilgers, Ralf-Dieter; Roes, Kit; Stallard, Nigel

2016-06-14

Most statistical design and analysis methods for clinical trials have been developed and evaluated where at least several hundreds of patients could be recruited. These methods may not be suitable to evaluate therapies if the sample size is unavoidably small, which is usually termed by small populations. The specific sample size cut off, where the standard methods fail, needs to be investigated. In this paper, the authors present their view on new developments for design and analysis of clinical trials in small population groups, where conventional statistical methods may be inappropriate, e.g., because of lack of power or poor adherence to asymptotic approximations due to sample size restrictions. Following the EMA/CHMP guideline on clinical trials in small populations, we consider directions for new developments in the area of statistical methodology for design and analysis of small population clinical trials. We relate the findings to the research activities of three projects, Asterix, IDeAl, and InSPiRe, which have received funding since 2013 within the FP7-HEALTH-2013-INNOVATION-1 framework of the EU. As not all aspects of the wide research area of small population clinical trials can be addressed, we focus on areas where we feel advances are needed and feasible. The general framework of the EMA/CHMP guideline on small population clinical trials stimulates a number of research areas. These serve as the basis for the three projects, Asterix, IDeAl, and InSPiRe, which use various approaches to develop new statistical methodology for design and analysis of small population clinical trials. Small population clinical trials refer to trials with a limited number of patients. Small populations may result form rare diseases or specific subtypes of more common diseases. New statistical methodology needs to be tailored to these specific situations. The main results from the three projects will constitute a useful toolbox for improved design and analysis of small

Hanford protective barriers program: Status of asphalt barrier studies - FY 1989

International Nuclear Information System (INIS)

Freeman, H.D.; Gee, G.W.

1989-11-01

The Hanford Protective Barrier Program is evaluating alternate barriers to provide a means of meeting stringent water infiltration requirements. One type of alternate barrier being considered is an asphalt-based layer, 1.3 to 15 cm thick. Evaluations of these barriers were initiated in FY 1988, and, based on laboratory studies, two asphalt formulations were selected for further testing in small-tube lysimeters: a hot rubberized asphalt and an admixture of cationic asphalt emulsion and concrete sand containing 24 wt% residual asphalt. Eight lysimeters containing asphalt seals were installed as part of the Small Tube Lysimeter Test Facility on the Hanford Site. Two control lysimeters containing Hanford sand with a surface gravel treatment were also installed for comparison. 5 refs., 13 figs., 1 tab

Small mammal populations at hazardous waste disposal sites near Houston, Texas, USA

Science.gov (United States)

Robbins, C.S.

1990-01-01

Small mammals were trapped, tagged and recaptured in 0?45 ha plots at six hazardous industrial waste disposal sites to determine if populations, body mass and age structures were different from paired control site plots. Low numbers of six species of small mammals were captured on industrial waste sites or control sites. Only populations of hispid cotton rats at industrial waste sites and control sites were large enough for comparisons. Overall population numbers, age structure, and body mass of adult male and female cotton rats were similar at industrial waste sites and control sites. Populations of small mammals (particularly hispid cotton rats) may not suffice as indicators of environments with hazardous industrial waste contamination.

Primary human polarized small intestinal epithelial barriers respond differently to a hazardous and an innocuous protein.

Science.gov (United States)

Eaton, A D; Zimmermann, C; Delaney, B; Hurley, B P

2017-08-01

An experimental platform employing human derived intestinal epithelial cell (IEC) line monolayers grown on permeable Transwell ® filters was previously investigated to differentiate between hazardous and innocuous proteins. This approach was effective at distinguishing these types of proteins and perturbation of monolayer integrity, particularly transepithelial electrical resistance (TEER), was the most sensitive indicator. In the current report, in vitro indicators of monolayer integrity, cytotoxicity, and inflammation were evaluated using primary (non-transformed) human polarized small intestinal epithelial barriers cultured on Transwell ® filters to compare effects of a hazardous protein (Clostridium difficile Toxin A [ToxA]) and an innocuous protein (bovine serum albumin [BSA]). ToxA exerted a reproducible decrease on barrier integrity at doses comparable to those producing effects observed from cell line-derived IEC monolayers, with TEER being the most sensitive indicator. In contrast, BSA, tested at concentrations substantially higher than ToxA, did not cause changes in any of the tested variables. These results demonstrate a similarity in response to certain proteins between cell line-derived polarized IEC models and a primary human polarized small intestinal epithelial barrier model, thereby reinforcing the potential usefulness of cell line-derived polarized IECs as a valid experimental platform to differentiate between hazardous and non-hazardous proteins. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Charge modification of the endothelial surface layer modulates the permeability barrier of isolated rat mesenteric small arteries

NARCIS (Netherlands)

van Haaren, Paul M. A.; VanBavel, Ed; Vink, Hans; Spaan, Jos A. E.

2005-01-01

We hypothesized that modulation of the effective charge density of the endothelial surface layer ( ESL) results in altered arterial barrier properties to transport of anionic solutes. Rat mesenteric small arteries ( diameter similar to 190 mu m) were isolated, cannulated, perfused, and superfused

LGBT Populations' Barriers to Cancer Care.

Science.gov (United States)

Boehmer, Ulrike

2018-02-01

To describe lesbian, gay, bisexual, and transgender (LGBT) individuals' barriers to accessing and receiving quality cancer care. Published data on cancer care and studies of LGBT individuals. There is a clustering of barriers among LGBT individuals, which suggests multiple inequities exist in LGBT individuals' cancer care, although data on disparities along the cancer control continuum are not consistently available. Nurses can make a difference in LGBT individuals' cancer care by obtaining training on LGBT health and their cancer-related needs and by providing a welcoming and respectful relationship with LGBT patients. Copyright © 2017 Elsevier Inc. All rights reserved.

Substance Abuse among the Deaf Population: An Overview of Current Strategies, Programs and Barriers to Recovery.

Science.gov (United States)

Lane, Katherine E.

1989-01-01

The paper analyzes the problem of alcohol and drug abuse among the deaf population focusing on: precipitating factors leading to substance abuse; barriers to recovery; and descriptions of several treatment centers, programs, and services. (JDD)

Patient-Reported Barriers to the Prekidney Transplant Evaluation in an At-Risk Population in the United States.

Science.gov (United States)

Lockwood, Mark B; Saunders, Milda R; Nass, Rachel; McGivern, Claire L; Cunningham, Patrick N; Chon, W James; Josephson, Michelle A; Becker, Yolanda T; Lee, Christopher S

2017-06-01

Despite our knowledge of barriers to the early stages of the transplant process, we have limited insight into patient-reported barriers to the prekidney transplant medical evaluation in populations largely at-risk for evaluation failure. One-hundred consecutive adults were enrolled at an urban, Midwestern transplant center. Demographic, clinical, and quality of life data were collected prior to patients visit with a transplant surgeon/nephrologist (evaluation begins). Patient-reported barriers to evaluation completion were collected using the Subjective Barriers Questionnaire 90-days after the initial medical evaluation appointment (evaluation ends), our center targeted goal for transplant work-up completion. At 90 days, 40% of participants had not completed the transplant evaluation. Five barrier categories were created from the 85 responses to the Subjective Barriers Questionnaire. Patient-reported barriers included poor communication, physical health, socioeconomics, psychosocial influences, and access to care. In addition, determinants for successful evaluation completion included being of white race, higher income, free of dialysis, a lower comorbid burden, and reporting higher scores on the Kidney Disease Quality of Life subscale role-emotional. Poor communication between patients and providers, and among providers, was the most prominent patient-reported barrier identified. Barriers were more prominent in marginalized groups such as ethnic minorities and people with low income. Understanding the prevalence of patient-reported barriers may aid in the development of patient-centered interventions to improve completion rates.

Real-time estimation of small-area populations with human biomarkers in sewage

Energy Technology Data Exchange (ETDEWEB)

Daughton, Christian G., E-mail: daughton.christian@epa.gov

2012-01-01

A new approach is conceptualized for measuring small-area human populations by using biomarkers in sewage. The basis for the concept (SCIM: Sewage Chemical-Information Mining) is supported by a comprehensive examination and synthesis of data published across several disciplines, including medicine, microbiology, clinical chemistry, and environmental science. Accurate measures of human populations are fundamental to numerous disciplines, including economics, marketing, politics, sociology, public health and safety (e.g., disease management; assessment of natural hazards; disaster prevention and response), quality of life, and the environment. Knowing the size, distribution, and flow of a small-area (local) population facilitates understanding the numerous and complex linkages and interactions between humans and the environment. Examples include material-flow (substance-flow) analysis, determining the magnitude of per capita contribution of pollutant loadings to watersheds, or forecasting future impacts of local populations on the environment or a population's demands on resources. While no definitive approach exists for measuring small-area populations, census-taking is a long-established convention. No approach exists, however, for gauging small-area populations in real-time, as none is able to capture population dynamics, which involve transient changes (e.g., daily influx and efflux) and lasting changes (e.g., births, deaths, change in residence). Accurate measurement of small-area populations in real time has never been possible but is essential for facilitating the design of more sustainable communities. Real-time measurement would provide communities the capability of testing what-if scenarios in design and policy decisions. After evaluation of a range of biomarkers (including the nitrogenous waste product creatinine, which has been long used in clinical chemistry as a parameter to normalize the concentrations of other urinary excretion products to

Changes to zooplankton community structure following colonization of a small lake by Leptodora kindti

Science.gov (United States)

McNaught, A.S.; Kiesling, R.L.; Ghadouani, A.

2004-01-01

The predaceous cladoceran Leptodora kindti (Focke) became established in Third Sister Lake, Michigan, after individuals escaped from experimental enclosures in 1987. By 1988, the Leptodora population exhibited seasonal dynamics characteristic of natural populations. The maximum seasonal abundance of Leptodora increased to 85 individuals m-3 3 yr following the introduction. After the appearance of Leptodora, small-bodied cladocerans (Ceriodaphnia and Bosmina) virtually disappeared from the lake. There were strong seasonal shifts in the dominance patterns of both cladocerans and copepods, and Daphnia species diversity increased. Results from this unplanned introduction suggest that invertebrate predators can have a rapid and lasting effect on prey populations, even in the presence of planktivorous fish. Small-scale (<20 km) geographic barriers might be as important as large-scale barriers to dispersal of planktonic animals.

Stability of barrier buckets with zero RF-barrier separations

Energy Technology Data Exchange (ETDEWEB)

Ng, K.Y.; /Fermilab

2005-03-01

A barrier bucket with very small separation between the rf barriers (relative to the barrier widths) or even zero separation has its synchrotron tune decreasing rather slowly from a large value towards the boundary of the bucket. As a result, large area at the bucket edges can become unstable under the modulation of rf voltage and/or rf phase. In addition, chaotic regions may form near the bucket center and extend outward under increasing modulation. Application is made to those barrier buckets used in the process of momentum mining at the Fermilab Recycler Ring.

The role of marine reserves in the replenishment of a locally-impacted population of anemonefish on the Great Barrier Reef

KAUST Repository

Bonin, Mary C.; Harrison, Hugo B.; Williamson, David H.; Frisch, Ashley J.; Saenz Agudelo, Pablo; Berumen, Michael L.; Jones, Geoffrey P.

2015-01-01

The development of parentage analysis to track the dispersal of juvenile offspring has given us unprecedented insight into the population dynamics of coral reef fishes. These tools now have the potential to inform fisheries management and species conservation, particularly for small fragmented populations under threat from exploitation and disturbance. In this study we resolve patterns of larval dispersal for a population of the anemonefish Amphiprion melanopus in the Keppel Islands (southern Great Barrier Reef). Habitat loss and fishing appear to have impacted this population and a network of no-take marine reserves currently protects 75% of the potential breeders. Using parentage analysis, we estimate that 21% of recruitment in the island group was generated locally, and that breeding adults living in reserves were responsible for 79% (31 out of 39) of these of locally-produced juveniles. Overall, the network of reserves was fully connected via larval dispersal; however one reserve was identified as a critical source of larvae for the island group. The population in the Keppel Islands also appears to be well-connected to other source populations at least 60 km away, given that 79% (145 out of 184) of the juveniles sampled remained unassigned in the parentage analysis. We estimated the effective size of the A. melanopus metapopulation to be 745 (582-993 95% CI) and recommend continued monitoring of its genetic status. Maintaining connectivity with populations beyond the Keppel Islands and recovery of local recruitment habitat, potentially through active restoration of host anemone populations, will be important for its long-term persistence.

The role of marine reserves in the replenishment of a locally-impacted population of anemonefish on the Great Barrier Reef

KAUST Repository

Bonin, Mary C.

2015-11-21

The development of parentage analysis to track the dispersal of juvenile offspring has given us unprecedented insight into the population dynamics of coral reef fishes. These tools now have the potential to inform fisheries management and species conservation, particularly for small fragmented populations under threat from exploitation and disturbance. In this study we resolve patterns of larval dispersal for a population of the anemonefish Amphiprion melanopus in the Keppel Islands (southern Great Barrier Reef). Habitat loss and fishing appear to have impacted this population and a network of no-take marine reserves currently protects 75% of the potential breeders. Using parentage analysis, we estimate that 21% of recruitment in the island group was generated locally, and that breeding adults living in reserves were responsible for 79% (31 out of 39) of these of locally-produced juveniles. Overall, the network of reserves was fully connected via larval dispersal; however one reserve was identified as a critical source of larvae for the island group. The population in the Keppel Islands also appears to be well-connected to other source populations at least 60 km away, given that 79% (145 out of 184) of the juveniles sampled remained unassigned in the parentage analysis. We estimated the effective size of the A. melanopus metapopulation to be 745 (582-993 95% CI) and recommend continued monitoring of its genetic status. Maintaining connectivity with populations beyond the Keppel Islands and recovery of local recruitment habitat, potentially through active restoration of host anemone populations, will be important for its long-term persistence.

Population genetic structure and demographic history of small ...

African Journals Online (AJOL)

Population genetic structure and demographic history of small yellow croaker, ... diversity (0.0112 ± 0.0061 to 0.0141 ± 0.0075) were detected in the species. ... into two closely related clades, but did not appear to have any geographic ...

Fragmentation reduces regional-scale spatial genetic structure in a wind-pollinated tree because genetic barriers are removed.

Science.gov (United States)

Wang, Rong; Compton, Stephen G; Shi, Yi-Su; Chen, Xiao-Yong

2012-09-01

Gene flow strongly influences the regional genetic structuring of plant populations. Seed and pollen dispersal patterns can respond differently to the increased isolation resulting from habitat fragmentation, with unpredictable consequences for gene flow and population structuring. In a recently fragmented landscape we compared the pre- and post-fragmentation genetic structure of populations of a tree species where pollen and seed dispersal respond differentially to forest fragmentation generated by flooding. Castanopsis sclerophylla is wind-pollinated, with seeds that are dispersed by gravity and rodents. Using microsatellites, we found no significant difference in genetic diversity between pre- and post-fragmentation cohorts. Significant genetic structure was observed in pre-fragmentation cohorts, due to an unknown genetic barrier that had isolated one small population. Among post-fragmentation cohorts this genetic barrier had disappeared and genetic structure was significantly weakened. The strengths of genetic structuring were at a similar level in both cohorts, suggesting that overall gene flow of C. sclerophylla has been unchanged by fragmentation at the regional scale. Fragmentation has blocked seed dispersal among habitats, but this appears to have been compensated for by enhanced pollen dispersal, as indicated by the disappearance of a genetic barrier, probably as a result of increased wind speeds and easier pollen movement over water. Extensive pollen flow can counteract some negative effects of fragmentation and assist the long-term persistence of small remnant populations.

Trap-induced mass declines in small mammals: Mass as a population index

Science.gov (United States)

Dean E. Pearson; Yvette K. Ortega; Leonard F. Ruggiero

2003-01-01

Body mass is routinely used as an index of physical condition for comparing small-mammal populations. However, trapping effects on animals may undermine the effectiveness of body mass as an index of population health. We examined the effects of live-trapping on body mass of 3 small-mammal species: deer mice (Peromyscus maniculatus), southern red-...

Barriers to disaster preparedness among medical special needs populations

Directory of Open Access Journals (Sweden)

Leslie eMeyer

2015-09-01

Full Text Available A medical special needs (MSN assessment was conducted among 3088 respondents in a hurricane prone area. The sample was female (51.7%, Hispanic (92.9%, aged > 45 years (51%, not insured for health (59.2%, and with an MSN (33.2%. Barriers to preparedness were characterized for all households, including those with inhabitants reporting MSN ranging from level 0 (mild to level 4 (most severe. Multivariable logistic regression tested associations between hurricane preparedness and barriers to evacuation by level of MSN. A significant interaction effect between number of evacuation barriers and MSN was found. Among households that reported individuals with level 0 MSN, the odds of being unprepared increased 18% for each additional evacuation barrier [OR=1.18, 95% CI (1.08, 1.30]. Among households that reported individuals with level 1 MSN, the odds of being unprepared increased 29% for each additional evacuation barrier [OR=1.29, 95% CI (1.11, 1.51]. Among households that reported individuals with level 3 MSN, the odds of being unprepared increased 68% for each additional evacuation barrier [OR=1.68, 95% CI (1.21, 1.32]. MSN alone did not explain the probability of unpreparedness, but rather MSN in the presence of barriers helped explain unpreparedness.

Barriers to reducing climate enhanced disaster risks in Least Developed Country-Small Islands through anticipatory adaptation

Directory of Open Access Journals (Sweden)

Natasha Kuruppu

2015-03-01

Full Text Available Small Island Developing States (SIDS classified as Least Developed Countries (LDCs are particularly vulnerable to the projected impacts of climate change. Given their particular vulnerabilities, climate adaptation investments are being made through both national and international efforts to build the capacity of various sectors and communities to reduce climate risks and associated disasters. Despite these efforts, reducing climate risks is not free of various challenges and barriers. This paper aims to synthesise a set of critical socio-economic barriers present at various spatial scales that are specific to Least Developed Country SIDS. It also aims to identify the processes that give rise to these barriers. Drawing on theories from natural hazards, a systematic literature review method was adopted to identify and organise the set of barriers by focussing on both academic papers and grey literature. The data revealed a notable lack of studies on adaptation within African and Caribbean LDC-SIDS. In general, there was a paucity of academic as well as grey literature being produced by authors from LDC-SIDS to challenge existing discourses related to adaptation barriers. The most common barriers identified included those related to governance, technical, cognitive and cultural. Three key findings can be drawn from this study in relation to formal adaptation initiatives. Firstly, the lack of focus on the adaptive capacity needs of Local Government or Island Councils and communities was a key barrier to ensure success of adaptation interventions. Secondly, international adaptation funding modalities did little to address root causes of vulnerability or support system transformations. These funds were geared at supporting sectoral level adaptation initiatives for vulnerable natural resource sectors such as water, biodiversity and coastal zones. Thirdly, there is a need to recognise the significance of cultural knowledge and practices in shaping

Barriers to reducing climate enhanced disaster risks in Least Developed Country-Small Islands through anticipatory adaptation

Science.gov (United States)

Kuruppu, N.; Willie, R.

2015-12-01

Small Island Developing States (SIDS) classified as Least Developed Countries (LDCs) are particularly vulnerable to the projected impacts of climate change. Given their particular vulnerabilities, climate adaptation investments are being made through both national and international efforts to build the capacity of various sectors and communities to reduce climate risks and associated disasters. Despite these efforts, reducing climate risks is not free of various challenges and barriers. This paper aims to synthesise a set of critical socio-economic barriers present at various spatial scales that are specific to Least Developed Country SIDS. It also aims to identify the processes that give rise to these barriers. Drawing on theories from natural hazards, a systematic literature review method was adopted to identify and organise the set of barriers by focussing both on academic papers and grey literature. The data revealed a notable lack of studies on adaptation within African and Caribbean LDC-SIDS. In general, there was a paucity of academic as well as grey literature being produced by authors from LDC-SIDS to challenge existing discourses related to adaptation barriers. The most common barriers identified included those related to governance, technical, cognitive and cultural. Three key findings can be drawn from this study in relation to formal adaptation initiatives. Firstly, the lack of focus on the adaptive capacity needs of Local Government or Island Councils and communities was a key barrier to ensuring success of adaptation interventions. Secondly, international adaptation funding modalities did little to address root causes of vulnerability or support system transformations. These funds were geared at supporting sectoral level adaptation initiatives for vulnerable natural resource sectors such as water, biodiversity and coastal zones. Thirdly, there is a need to recognise the significance of cultural knowledge and practices in shaping adaptive choices of

Breakthrough revisited: investigating the requirements for growth of dust beyond the bouncing barrier

Science.gov (United States)

Booth, Richard A.; Meru, Farzana; Lee, Man Hoi; Clarke, Cathie J.

2018-03-01

For grain growth to proceed effectively and lead to planet formation, a number of barriers to growth must be overcome. One such barrier, relevant for compact grains in the inner regions of the disc, is the `bouncing barrier' in which large grains (˜mm size) tend to bounce off each other rather than sticking. However, by maintaining a population of small grains, it has been suggested that cm-size particles may grow rapidly by sweeping up these small grains. We present the first numerically resolved investigation into the conditions under which grains may be lucky enough to grow beyond the bouncing barrier by a series of rare collisions leading to growth (so-called `breakthrough'). Our models support previous results, and show that in simple models breakthrough requires the mass ratio at which high-velocity collisions transition to growth instead of causing fragmentation to be low, ϕ ≲ 50. However, in models that take into account the dependence of the fragmentation threshold on mass ratio, we find that breakthrough occurs more readily, even if mass transfer is relatively inefficient. This suggests that bouncing may only slow down growth, rather than preventing growth beyond a threshold barrier. However, even when growth beyond the bouncing barrier is possible, radial drift will usually prevent growth to arbitrarily large sizes.

Diversity of human small intestinal Streptococcus and Veillonella populations.

Science.gov (United States)

van den Bogert, Bartholomeus; Erkus, Oylum; Boekhorst, Jos; de Goffau, Marcus; Smid, Eddy J; Zoetendal, Erwin G; Kleerebezem, Michiel

2013-08-01

Molecular and cultivation approaches were employed to study the phylogenetic richness and temporal dynamics of Streptococcus and Veillonella populations in the small intestine. Microbial profiling of human small intestinal samples collected from four ileostomy subjects at four time points displayed abundant populations of Streptococcus spp. most affiliated with S. salivarius, S. thermophilus, and S. parasanguinis, as well as Veillonella spp. affiliated with V. atypica, V. parvula, V. dispar, and V. rogosae. Relative abundances varied per subject and time of sampling. Streptococcus and Veillonella isolates were cultured using selective media from ileostoma effluent samples collected at two time points from a single subject. The richness of the Streptococcus and Veillonella isolates was assessed at species and strain level by 16S rRNA gene sequencing and genetic fingerprinting, respectively. A total of 160 Streptococcus and 37 Veillonella isolates were obtained. Genetic fingerprinting differentiated seven Streptococcus lineages from ileostoma effluent, illustrating the strain richness within this ecosystem. The Veillonella isolates were represented by a single phylotype. Our study demonstrated that the small intestinal Streptococcus populations displayed considerable changes over time at the genetic lineage level because only representative strains of a single Streptococcus lineage could be cultivated from ileostoma effluent at both time points. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Molecular computational elements encode large populations of small objects

Science.gov (United States)

Prasanna de Silva, A.; James, Mark R.; McKinney, Bernadine O. F.; Pears, David A.; Weir, Sheenagh M.

2006-10-01

Since the introduction of molecular computation, experimental molecular computational elements have grown to encompass small-scale integration, arithmetic and games, among others. However, the need for a practical application has been pressing. Here we present molecular computational identification (MCID), a demonstration that molecular logic and computation can be applied to a widely relevant issue. Examples of populations that need encoding in the microscopic world are cells in diagnostics or beads in combinatorial chemistry (tags). Taking advantage of the small size (about 1nm) and large `on/off' output ratios of molecular logic gates and using the great variety of logic types, input chemical combinations, switching thresholds and even gate arrays in addition to colours, we produce unique identifiers for members of populations of small polymer beads (about 100μm) used for synthesis of combinatorial libraries. Many millions of distinguishable tags become available. This method should be extensible to far smaller objects, with the only requirement being a `wash and watch' protocol. Our focus on converting molecular science into technology concerning analog sensors, turns to digital logic devices in the present work.

The influence of natural barriers in shaping the genetic structure of Maharashtra populations.

Science.gov (United States)

Thangaraj, Kumarasamy; Naidu, B Prathap; Crivellaro, Federica; Tamang, Rakesh; Upadhyay, Shashank; Sharma, Varun Kumar; Reddy, Alla G; Walimbe, S R; Chaubey, Gyaneshwer; Kivisild, Toomas; Singh, Lalji

2010-12-20

The geographical position of Maharashtra state makes it rather essential to study the dispersal of modern humans in South Asia. Several hypotheses have been proposed to explain the cultural, linguistic and geographical affinity of the populations living in Maharashtra state with other South Asian populations. The genetic origin of populations living in this state is poorly understood and hitherto been described at low molecular resolution level. To address this issue, we have analyzed the mitochondrial DNA (mtDNA) of 185 individuals and NRY (non-recombining region of Y chromosome) of 98 individuals belonging to two major tribal populations of Maharashtra, and compared their molecular variations with that of 54 South Asian contemporary populations of adjacent states. Inter and intra population comparisons reveal that the maternal gene pool of Maharashtra state populations is composed of mainly South Asian haplogroups with traces of east and west Eurasian haplogroups, while the paternal haplogroups comprise the South Asian as well as signature of near eastern specific haplogroup J2a. Our analysis suggests that Indian populations, including Maharashtra state, are largely derived from Paleolithic ancient settlers; however, a more recent (∼10 Ky older) detectable paternal gene flow from west Asia is well reflected in the present study. These findings reveal movement of populations to Maharashtra through the western coast rather than mainland where Western Ghats-Vindhya Mountains and Narmada-Tapti rivers might have acted as a natural barrier. Comparing the Maharastrian populations with other South Asian populations reveals that they have a closer affinity with the South Indian than with the Central Indian populations.

Barriers to Energy Efficiency in Swedish Non-Energy-Intensive Micro- and Small-Sized Enterprises—A Case Study of a Local Energy Program

Directory of Open Access Journals (Sweden)

Fredrik Backman

2017-01-01

Full Text Available Improved energy efficiency has become a strategic issue and represents a priority for European competitiveness. Countries adopt various energy policies on local and national levels where energy audit programs are the most common energy end-use efficiency policy for industrial small- and medium-sized enterprises (SMEs. However, studies indicate that cost-efficient energy conservation measures are not always implemented, which can be explained by the existence of barriers to energy efficiency. This paper investigates how Swedish municipalities can support local micro- and small-sized enterprises with improved energy efficiency and the existence of different barriers to the implementation of energy efficiency. Relating this empirical case study to the theoretical barriers outlined in the text, this study found that the major explanatory factors related to non-implementation of cost-effective energy efficiency measures among micro- and small-sized industrial enterprises were bounded rationality (lack of time and/or other priorities, split incentives (having other priorities for capital investments, and imperfect information (slim organization and lack of technical skill. This study also found that information in the form of a report was the main thing that companies gained from working on the project “Energy-Driven Business”. Notably, the study involved companies that had participated in a local energy program and, still, companies face major barriers inhibiting implementation, indicating a need to further study other alternative policy models and how knowledge transfer can be improved.

Neurobehavioral endocrine regulation of small mammal populations

International Nuclear Information System (INIS)

Christian, J.J.

1978-01-01

A brief review is given of the hypothesis that density-dependent behavioral-endocrine negative feedbacks can regulate and often limit the growth of populations of many species of small mammals. Recent laboratory studies are summarized that show how stress, particularly psychogenic, which results in increased adrenocortical secretion also alters gonadotropin secretion and inhibits reproduction. Chronic stress due to crowding, immobilization, et al. inhibits the release of LH and FSH, particularly by abolishing the pulsatile release of LH, and also causes a rise in prolactin (at least acutely). Stimulation of the hypothalamo-pituitary-adrenocortical system is accompanied by an inversely proportional inhibition of growth hormone secretion. Decreasing photoperiod enhances the sensitivity of the hypothalamus to inhibition of gonadotropin secretion by androgens and estrogens. Other endocrine responses to increased density or subordinate social rank also are summarized. How these facts fit into the negative feedback scheme is discussed, including the greatly prolonged effects of diminished lactation. The changed quality of the animals associated with changes in density discussed by Lidicker also can be explained by the above responses to density. Data on changes in growth and reproductive function which are consistent with the behavioral-endocrine feedback hypothesis are presented for several populations of small mammals, including some previously unpublished data for Microtus pennsylvanicus

BARRIERS IN IMPLEMENTATION OF E-BUSINESS TECHNOLOGIES IN SMALL AND MEDIUM ENTERPRISES (SMEs IN PAKISTAN

Directory of Open Access Journals (Sweden)

Anwar Ali Shah G. SYED

2012-05-01

Full Text Available The current research investigates the Barriers in implementation of E-Business Technologies in Small and Medium enterprises (SMEs in Pakistan. Data were collected from 2000 respondents by using simple random technique. A structural questionnaire was developed for the data collection and reliability and validity of data. It was revealed that most of the SMEs business owners are not familiar in using internet and in many cases they are not computer literate. It was further revealed that Government should provide some basic computer training to the Small and Medium Enterprises so they will able to use computer. The proper implementation of E-Business technologies in SMEs in Pakistan, Government and other related agencies can initiate E-Business in SMEs to achieve competitive edge.

Host-dependent zonulin secretion causes the impairment of the small intestine barrier function after bacterial exposure.

Science.gov (United States)

El Asmar, Ramzi; Panigrahi, Pinaki; Bamford, Penelope; Berti, Irene; Not, Tarcisio; Coppa, Giovanni V; Catassi, Carlo; Fasano, Alessio; El Asmar, Rahzi

2002-11-01

Enteric infections have been implicated in the pathogenesis of both food intolerance and autoimmune diseases secondary to the impairment of the intestinal barrier. On the basis of our recent discovery of zonulin, a modulator of small-intestinal tight junctions, we asked whether microorganisms might induce zonulin secretion and increased small-intestinal permeability. Both ex vivo mammalian small intestines and intestinal cell monolayers were exposed to either pathogenic or nonpathogenic enterobacteria. Zonulin production and changes in paracellular permeability were monitored in Ussing chambers and micro-snapwells. Zonula occludens 1 protein redistribution after bacteria colonization was evaluated on cell monolayers. Small intestines exposed to enteric bacteria secreted zonulin. This secretion was independent of either the species of the small intestines or the virulence of the microorganisms tested, occurred only on the luminal aspect of the bacteria-exposed small-intestinal mucosa, and was followed by a decrease in small-intestinal tissue resistance (transepithelial electrical resistance). The transepithelial electrical resistance decrement was secondary to the zonulin-induced tight junction disassembly, as also shown by the disengagement of the protein zonula occludens 1 protein from the tight junctional complex. This zonulin-driven opening of the paracellular pathway may represent a defensive mechanism, which flushes out microorganisms and contributes to the host response against bacterial colonization of the small intestine.

Estimating small area health-related characteristics of populations: a methodological review

Directory of Open Access Journals (Sweden)

Azizur Rahman

2017-05-01

Full Text Available Estimation of health-related characteristics at a fine local geographic level is vital for effective health promotion programmes, provision of better health services and population-specific health planning and management. Lack of a micro-dataset readily available for attributes of individuals at small areas negatively impacts the ability of local and national agencies to manage serious health issues and related risks in the community. A solution to this challenge would be to develop a method that simulates reliable small-area statistics. This paper provides a significant appraisal of the methodologies for estimating health-related characteristics of populations at geographical limited areas. Findings reveal that a range of methodologies are in use, which can be classified as three distinct set of approaches: i indirect standardisation and individual level modelling; ii multilevel statistical modelling; and iii micro-simulation modelling. Although each approach has its own strengths and weaknesses, it appears that microsimulation- based spatial models have significant robustness over the other methods and also represent a more precise means of estimating health-related population characteristics over small areas.

Predictors of perceived barriers to physical activity in the general adult population: a cross-sectional study.

Science.gov (United States)

Herazo-Beltrán, Yaneth; Pinillos, Yisel; Vidarte, José; Crissien, Estela; Suarez, Damaris; García, Rafael

The perception of personal barriers to physical activity varies according to the sociodemographic characteristics of individuals. To determine the predictors of the perception of barriers to physical activity in the adult population. A cross-sectional study with 1066 adult women and 1036 adult men. The sociodemographic variables (age, gender, marital status, socioeconomic level, level of education), the perception of barriers that do not allow performance of physical activity (i.e. lack of time, social support, energy, motivation, skill, resources, and fear of injury during practice); and the level of physical activity through the International Physical Activity Questionnaire in its short-form version were evaluated. Individuals from low socioeconomic level (1 and 2) have higher risks of perceiving barriers such as lack of motivation [OR 1.76 (95% CI (1.4-2.1))] and lack of resources [OR 1.37 (95% CI (1.1-1.6))]; individuals with partners did not perceive the lack of social support [OR 0.29 (95% CI (0.2-0.4))] and lack of motivation [OR 0.54 (95% CI (0.4-0.7))] as barriers to physical activity. Individuals with low schooling perceived lack of social support [OR 3.81 (95% CI (3-4.7))], lack of resources [OR 2.78 (95% CI (2.2-3.3))], and fear of injury [OR 2.70 (95% CI (2.2-3.3))] as barrier to physical activity. Factors such as socioeconomic level, marital status, level of education, and self-perception of health are predictors of barriers to physical activity. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

Genetic analysis reveals demographic fragmentation of grizzly bears yielding vulnerably small populations.

Science.gov (United States)

Proctor, Michael F; McLellan, Bruce N; Strobeck, Curtis; Barclay, Robert M R

2005-11-22

Ecosystem conservation requires the presence of native carnivores, yet in North America, the distributions of many larger carnivores have contracted. Large carnivores live at low densities and require large areas to thrive at the population level. Therefore, if human-dominated landscapes fragment remaining carnivore populations, small and demographically vulnerable populations may result. Grizzly bear range contraction in the conterminous USA has left four fragmented populations, three of which remain along the Canada-USA border. A tenet of grizzly bear conservation is that the viability of these populations requires demographic linkage (i.e. inter-population movement of both sexes) to Canadian bears. Using individual-based genetic analysis, our results suggest this demographic connection has been severed across their entire range in southern Canada by a highway and associated settlements, limiting female and reducing male movement. Two resulting populations are vulnerably small (bear populations may be more threatened than previously thought and that conservation efforts must expand to include international connectivity management. They also demonstrate the ability of genetic analysis to detect gender-specific demographic population fragmentation in recently disturbed systems, a traditionally intractable yet increasingly important ecological measurement worldwide.

The influence of natural barriers in shaping the genetic structure of Maharashtra populations.

Directory of Open Access Journals (Sweden)

Kumarasamy Thangaraj

Full Text Available BACKGROUND: The geographical position of Maharashtra state makes it rather essential to study the dispersal of modern humans in South Asia. Several hypotheses have been proposed to explain the cultural, linguistic and geographical affinity of the populations living in Maharashtra state with other South Asian populations. The genetic origin of populations living in this state is poorly understood and hitherto been described at low molecular resolution level. METHODOLOGY/PRINCIPAL FINDINGS: To address this issue, we have analyzed the mitochondrial DNA (mtDNA of 185 individuals and NRY (non-recombining region of Y chromosome of 98 individuals belonging to two major tribal populations of Maharashtra, and compared their molecular variations with that of 54 South Asian contemporary populations of adjacent states. Inter and intra population comparisons reveal that the maternal gene pool of Maharashtra state populations is composed of mainly South Asian haplogroups with traces of east and west Eurasian haplogroups, while the paternal haplogroups comprise the South Asian as well as signature of near eastern specific haplogroup J2a. CONCLUSIONS/SIGNIFICANCE: Our analysis suggests that Indian populations, including Maharashtra state, are largely derived from Paleolithic ancient settlers; however, a more recent (∼10 Ky older detectable paternal gene flow from west Asia is well reflected in the present study. These findings reveal movement of populations to Maharashtra through the western coast rather than mainland where Western Ghats-Vindhya Mountains and Narmada-Tapti rivers might have acted as a natural barrier. Comparing the Maharastrian populations with other South Asian populations reveals that they have a closer affinity with the South Indian than with the Central Indian populations.

Strategies to overcome barriers for cleaner generation technologies in small developing power systems: Sri Lanka case study

International Nuclear Information System (INIS)

Wijayatunga, Priyantha D.C.; Siriwardena, Kanchana; Fernando, W.J.L.S.; Shrestha, Ram M.; Attalage, Rahula A.

2006-01-01

The penetration of cleaner and energy efficient technologies in small power systems such as the one in Sri Lanka has encountered many problems. This has caused major concerns among the policy makers, mainly in the context of the growing need to reduce harmful emissions in the electricity supply industry from the point of view of both local environmental pollution as well as the global warming concerns. This paper presents the outcome of a study involved in identifying and ranking the barriers to the promotion of cleaner and energy efficient technologies and strategies to overcome these barriers in Sri Lanka. Barriers for renewable energy based systems such as wind and wood fuel fired plants (dendro thermal power) and cleaner technologies such as liquefied natural gas (LNG) fired combined cycle and IGCC (coal) were identified based on a survey. A direct assessment multi-criteria decision making method called Analytic Hierarchy Process (AHP) was used to rank the barriers. The most effective strategies are proposed to address the three major barriers for each of these technologies based on extensive discussions with all the stakeholders in the electricity industry. It was found that lack of financing instruments, high initial cost and lack of assurance of resource supply or availability are the main barriers for renewable technologies. As for cleaner fuel and technology options associated with conventional generation systems, the lack of a clear government policy, uncertainty of fuel supplies and their prices and the reliability of the technologies themselves are the major barriers. Strategies are identified to overcome the above barriers. Establishment of a proper feed in tariff, geographical diversification of installations and capacity building in commercial banks are suggested for wind power. Investment incentives, streamlining of wood production and research on site identification are proposed for wood fuel fired plants. Also the study suggests delayed

How to conserve threatened Chinese plant species with extremely small populations?

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Sergei Volis

2016-02-01

Full Text Available The Chinese flora occupies a unique position in global plant diversity, but is severely threatened. Although biodiversity conservation in China has made significant progress over the past decades, many wild plant species have extremely small population sizes and therefore are in extreme danger of extinction. The concept of plant species with extremely small populations (PSESPs, recently adopted and widely accepted in China, lacks a detailed description of the methodology appropriate for conserving PSESPs. Strategies for seed sampling, reintroduction, protecting PSESP locations, managing interactions with the local human population, and other conservation aspects can substantially differ from those commonly applied to non-PSESPs. The present review is an attempt to provide a detailed conservation methodology with realistic and easy-to-follow guidelines for PSESPs in China.

Antimicrobial Peptides, Infections and the Skin Barrier

DEFF Research Database (Denmark)

Clausen, Maja Lisa; Agner, Tove

2016-01-01

The skin serves as a strong barrier protecting us from invading pathogens and harmful organisms. An important part of this barrier comes from antimicrobial peptides (AMPs), which are small peptides expressed abundantly in the skin. AMPs are produced in the deeper layers of the epidermis and trans......The skin serves as a strong barrier protecting us from invading pathogens and harmful organisms. An important part of this barrier comes from antimicrobial peptides (AMPs), which are small peptides expressed abundantly in the skin. AMPs are produced in the deeper layers of the epidermis...

Barriers to prompt and effective malaria treatment among the poorest population in Kenya

Directory of Open Access Journals (Sweden)

Okungu Vincent

2010-05-01

Full Text Available Abstract Background Prompt access to effective malaria treatment is central to the success of malaria control worldwide, but few fevers are treated with effective anti-malarials within 24 hours of symptoms onset. The last two decades saw an upsurge of initiatives to improve access to effective malaria treatment in many parts of sub-Saharan Africa. Evidence suggests that the poorest populations remain least likely to seek prompt and effective treatment, but the factors that prevent them from accessing interventions are not well understood. With plans under way to subsidize ACT heavily in Kenya and other parts of Africa, there is urgent need to identify policy actions to promote access among the poor. This paper explores access barriers to effective malaria treatment among the poorest population in four malaria endemic districts in Kenya. Methods The study was conducted in the poorest areas of four malaria endemic districts in Kenya. Multiple data collection methods were applied including: a cross-sectional survey (n = 708 households; 24 focus group discussions; semi-structured interviews with health workers (n = 34; and patient exit interviews (n = 359. Results Multiple factors related to affordability, acceptability and availability interact to influence access to prompt and effective treatment. Regarding affordability, about 40 percent of individuals who self-treated using shop-bought drugs and 42 percent who visited a formal health facility reported not having enough money to pay for treatment, and having to adopt coping strategies including borrowing money and getting treatment on credit in order to access care. Other factors influencing affordability were seasonality of illness and income sources, transport costs, and unofficial payments. Regarding acceptability, the major interrelated factors identified were provider patient relationship, patient expectations, beliefs on illness causation, perceived effectiveness of treatment, distrust in

An example of population-level risk assessments for small mammals using individual-based population models.

Science.gov (United States)

Schmitt, Walter; Auteri, Domenica; Bastiansen, Finn; Ebeling, Markus; Liu, Chun; Luttik, Robert; Mastitsky, Sergey; Nacci, Diane; Topping, Chris; Wang, Magnus

2016-01-01

This article presents a case study demonstrating the application of 3 individual-based, spatially explicit population models (IBMs, also known as agent-based models) in ecological risk assessments to predict long-term effects of a pesticide to populations of small mammals. The 3 IBMs each used a hypothetical fungicide (FungicideX) in different scenarios: spraying in cereals (common vole, Microtus arvalis), spraying in orchards (field vole, Microtus agrestis), and cereal seed treatment (wood mouse, Apodemus sylvaticus). Each scenario used existing model landscapes, which differed greatly in size and structural complexity. The toxicological profile of FungicideX was defined so that the deterministic long-term first tier risk assessment would result in high risk to small mammals, thus providing the opportunity to use the IBMs for risk assessment refinement (i.e., higher tier risk assessment). Despite differing internal model design and scenarios, results indicated in all 3 cases low population sensitivity unless FungicideX was applied at very high (×10) rates. Recovery from local population impacts was generally fast. Only when patch extinctions occured in simulations of intentionally high acute toxic effects, recovery periods, then determined by recolonization, were of any concern. Conclusions include recommendations for the most important input considerations, including the selection of exposure levels, duration of simulations, statistically robust number of replicates, and endpoints to report. However, further investigation and agreement are needed to develop recommendations for landscape attributes such as size, structure, and crop rotation to define appropriate regulatory risk assessment scenarios. Overall, the application of IBMs provides multiple advantages to higher tier ecological risk assessments for small mammals, including consistent and transparent direct links to specific protection goals, and the consideration of more realistic scenarios. © 2015 SETAC.

Population growth rate and genetic variability of small and large populations of Red flour beetle (Tribolium castaneum) following multigenerational exposure to copper.

Science.gov (United States)

Laskowski, Ryszard; Radwan, Jacek; Kuduk, Katarzyna; Mendrok, Magdalena; Kramarz, Paulina

2015-07-01

We reared large (1000 individuals) and small (20 individuals) populations of Tribolium castaneum on diet contaminated with copper in order to determine if the size of a population affects its ability to adapt to adverse environmental conditions. After 10 generations, we used microsatellite markers to estimate and subsequently compare the genetic variability of the copper-treated populations with that of the control populations, which were reared on uncontaminated medium. Additionally, we conducted a full cross-factorial experiment which evaluated the effects of 10 generations of "pre-exposure" to copper on a population's fitness in control and copper-contaminated environments. In order to distinguish results potentially arising from genetic adaptation from those due to non-genetic effects associated to parental exposure to copper, we subjected also F11 generation, originating from parents not exposed to copper, to the same cross-factorial experiment. The effects of long-term exposure to copper depended on population size: the growth rates of small populations that were pre-exposed to copper were inhibited compared to those of small populations reared in uncontaminated environments. Large Cu-exposed populations had a higher growth rate in the F10 generation compared to the control groups, while the growth rate of the F11 generation was unaffected by copper exposure history. The only factor that had a significant effect on genetic variability was population size, but this was to be expected given the large difference in the number of individuals between large and small populations. Neither copper contamination nor its interaction with population size affected the number of microsatellite alleles retained in the F10 generation.

Genetic health and population monitoring of two small black bear (Ursus americanus populations in Alabama, with a regional perspective of genetic diversity and exchange.

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John P Draper

Full Text Available One of the major concerns in conservation today is the loss of genetic diversity which is a frequent consequence of population isolation and small population sizes. Fragmentation of populations and persecution of carnivores has posed a substantial threat to the persistence of free ranging carnivores in North America since the arrival of European settlers. Black bears have seen significant reductions in range size from their historic extent, which is most pronounced in the southeastern United States and even more starkly in Alabama where until recently bears were reduced to a single geographically isolated population in the Mobile River Basin. Recently a second population has naturally re-established itself in northeastern Alabama. We sought to determine size, genetic diversity and genetic connectivity for these two populations in relation to other regional populations. Both populations of black bears in Alabama had small population sizes and had moderate to low genetic diversity, but showed different levels of connectivity to surrounding populations of bears. The Mobile River Basin population had a small population size at only 86 individuals (76-124, 95% C.I., the lowest genetic diversity of compared populations (richness = 2.33, Ho and He = 0.33, and showed near complete genetic isolation from surrounding populations across multiple tests. The newly recolonizing population in northeastern Alabama had a small but growing population doubling in 3 years (34 individuals 26-43, 95% C.I., relatively moderate genetic diversity compared to surrounding populations (richness = 3.32, Ho = 0.53, He = 0.65, and showed a high level of genetic connectivity with surrounding populations.

Genetic health and population monitoring of two small black bear (Ursus americanus) populations in Alabama, with a regional perspective of genetic diversity and exchange.

Science.gov (United States)

Draper, John P; Waits, Lisette P; Adams, Jennifer R; Seals, Christopher L; Steury, Todd D

2017-01-01

One of the major concerns in conservation today is the loss of genetic diversity which is a frequent consequence of population isolation and small population sizes. Fragmentation of populations and persecution of carnivores has posed a substantial threat to the persistence of free ranging carnivores in North America since the arrival of European settlers. Black bears have seen significant reductions in range size from their historic extent, which is most pronounced in the southeastern United States and even more starkly in Alabama where until recently bears were reduced to a single geographically isolated population in the Mobile River Basin. Recently a second population has naturally re-established itself in northeastern Alabama. We sought to determine size, genetic diversity and genetic connectivity for these two populations in relation to other regional populations. Both populations of black bears in Alabama had small population sizes and had moderate to low genetic diversity, but showed different levels of connectivity to surrounding populations of bears. The Mobile River Basin population had a small population size at only 86 individuals (76-124, 95% C.I.), the lowest genetic diversity of compared populations (richness = 2.33, Ho and He = 0.33), and showed near complete genetic isolation from surrounding populations across multiple tests. The newly recolonizing population in northeastern Alabama had a small but growing population doubling in 3 years (34 individuals 26-43, 95% C.I.), relatively moderate genetic diversity compared to surrounding populations (richness = 3.32, Ho = 0.53, He = 0.65), and showed a high level of genetic connectivity with surrounding populations.

Ensembles of a small number of conformations with relative populations

Energy Technology Data Exchange (ETDEWEB)

Vammi, Vijay, E-mail: vsvammi@iastate.edu; Song, Guang, E-mail: gsong@iastate.edu [Iowa State University, Bioinformatics and Computational Biology Program, Department of Computer Science (United States)

2015-12-15

In our previous work, we proposed a new way to represent protein native states, using ensembles of a small number of conformations with relative Populations, or ESP in short. Using Ubiquitin as an example, we showed that using a small number of conformations could greatly reduce the potential of overfitting and assigning relative populations to protein ensembles could significantly improve their quality. To demonstrate that ESP indeed is an excellent alternative to represent protein native states, in this work we compare the quality of two ESP ensembles of Ubiquitin with several well-known regular ensembles or average structure representations. Extensive amount of significant experimental data are employed to achieve a thorough assessment. Our results demonstrate that ESP ensembles, though much smaller in size comparing to regular ensembles, perform equally or even better sometimes in all four different types of experimental data used in the assessment, namely, the residual dipolar couplings, residual chemical shift anisotropy, hydrogen exchange rates, and solution scattering profiles. This work further underlines the significance of having relative populations in describing the native states.

Understanding barriers to the introduction of precision medicines in non-small cell lung cancer: A qualitative interview protocol.

Science.gov (United States)

Wright, Stuart; Daker-White, Gavin; Newman, William; Payne, Katherine

2018-01-01

Background: While precision medicines targeting genetic mutations and alterations in non-small cell lung cancer (NSCLC) have been available since 2010, their adoption into clinical practice has been slow. Evidence suggests that a number of barriers, such as insufficient clinician knowledge, a need for training of test providers, or a lack of specific clinical guidelines, may slow the implementation of precision in general. However, little attention has been given to the barriers to providing precision medicines in NSCLC. The purpose of this protocol is to outline the design for a qualitative interview study to identify the barriers and facilitators to the provision of precision medicines for NSCLC. Methods: This study will use semi-structured interviews with clinicians (n=10), test providers (n=10), and service commissioners (n=10) to identify the perceived barriers and facilitators to providing historical, current, and future precision medicines in NSCLC. Participants will be identified through mailing list advertisements and snowball sampling. Recruitment will continue until data saturation, indicated by no new themes arising from the data. Interviews will be conducted by telephone to facilitate geographical diversity. The qualitative data will be analysed using a framework analysis with themes anticipated to relate to; relevant barriers to providing precision medicines, the impact of different barriers on medicine provision, changes in the ability to provide precision medicines over time, and strategies to facilitate the provision of precision medicines. Ethics: This study has been approved by the University of Manchester Proportionate Review Research Ethics Committee (Reference number: 2017-1885-3619). Written consent will be obtained from all participants. Conclusion: This study is the first to explore the barriers and facilitators to providing precision medicines for NSCLC in the English NHS. The findings will inform strategies to improve the implementation

Deciphering the landscape of host barriers to Listeria monocytogenes infection.

Science.gov (United States)

Zhang, Ting; Abel, Sören; Abel Zur Wiesch, Pia; Sasabe, Jumpei; Davis, Brigid M; Higgins, Darren E; Waldor, Matthew K

2017-06-13

Listeria monocytogenes is a common food-borne pathogen that can disseminate from the intestine and infect multiple organs. Here, we used sequence tag-based analysis of microbial populations (STAMP) to investigate L monocytogenes population dynamics during infection. We created a genetically barcoded library of murinized L monocytogenes and then used deep sequencing to track the pathogen's dissemination routes and quantify its founding population ( N b ) sizes in different organs. We found that the pathogen disseminates from the gastrointestinal tract to distal sites through multiple independent routes and that N b sizes vary greatly among tissues, indicative of diverse host barriers to infection. Unexpectedly, comparative analyses of sequence tags revealed that fecally excreted organisms are largely derived from the very small number of L. monocytogenes cells that colonize the gallbladder. Immune depletion studies suggest that distinct innate immune cells restrict the pathogen's capacity to establish replicative niches in the spleen and liver. Finally, studies in germ-free mice suggest that the microbiota plays a critical role in the development of the splenic, but not the hepatic, barriers that prevent L. monocytogenes from seeding these organs. Collectively, these observations illustrate the potency of the STAMP approach to decipher the impact of host factors on population dynamics of pathogens during infection.

Engineered barrier durability: An issue for disposal near populated areas

International Nuclear Information System (INIS)

Porter, C.L.

1995-01-01

Under the current national policy for disposal of low-level radioactive waste (LLW) in the United States of America, each State is required to provide disposal capacity for the LLW generated within its borders. The formation of ''Compacts'' of several States is allowed if approved by Congress. Such forced regionalization of disposal facilities based on State boundaries results in some disposal facilities being sited near populated areas at locations with less than optimum site characteristics from a disposal standpoint. To compensate for this engineered barriers are included in the proposed designs. Portland cement based concrete (PCC), which is the dominant material for disposal vault designs, is degraded via many mechanisms, most of which are related to its permeability. The numerous uncertainties associated with the long-term performance of PCC has lead to many unsuccessful attempts to obtain public acceptance of proposed disposal facilities. These unsuccessful efforts have delayed establishing disposal capacity to the point that a crisis is looming on the horizon. This paper investigates the results of on-going research into the viability of commercially available, impermeable, mass-poured construction materials as an alternative to PCC in LLW disposal vaults. The results from testing and research on two such materials, concrete made from sulfur polymer cement (SPC) and ICOM (an epoxy based concrete) are reported. Material properties and test results include strength parameters, chemical resistance, porosity, permeability, deconability, radiation damage resistance, and biodegradation. The data indicates that with these alternative materials the uncertainties in predicting service life of an engineered barrier can be reduced

Genome-scale data reveal that endemic Poecilia populations from small sulphidic springs display no evidence of inbreeding.

Science.gov (United States)

Brown, Anthony P; Greenway, Ryan; Morgan, Samuel; Quackenbush, Corey R; Giordani, Luca; Arias-Rodriguez, Lenin; Tobler, Michael; Kelley, Joanna L

2017-10-01

Populations with limited ranges can be highly vulnerable to changes in their environment and are, thus, of high conservation concern. Populations that experience human-induced range reductions are often highly inbred and lack genetic diversity, but it is unknown whether this is also the case for populations with naturally small ranges. The fishes Poecilia sulphuraria (listed as critically endangered) and Poecilia thermalis, which are endemic to small hydrogen sulphide-rich springs in southern Mexico, are examples of such populations with inherently small habitats. We used geometric morphometrics and population genetics to quantify phenotypic and genetic variation within and among two populations of P. sulphuraria and one population of P. thermalis. Principal component analyses revealed phenotypic and genetic differences among the populations. Evidence for inbreeding was low compared to populations that have undergone habitat reduction. The genetic data were also used to infer the demographic history of these populations to obtain estimates for effective population sizes and migration rates. Effective population sizes were large given the small habitats of these populations. Our results imply that these three endemic extremophile populations should each be considered separately for conservation purposes. Additionally, this study suggests that populations in naturally small habitats may have lower rates of inbreeding and higher genetic diversity than expected, and therefore may be better equipped to handle environmental perturbations than anticipated. We caution, however, that the inferred lack of inbreeding and the large effective population sizes could potentially be a result of colonization by genetically diverse ancestors. © 2017 John Wiley & Sons Ltd.

Characterization of small mammal populations inhabiting the B-C cribs environs

International Nuclear Information System (INIS)

Hedlund, J.D.; Rogers, L.E.

1976-12-01

The purpose of this study was to document the current status of small mammal populations inhibiting the 200 Area plateau near the B-C Crib management area and to compare them with populations inhabiting a protected (control) area within the confines of the Hanford ALE Reserve. Sampling sessions were conducted over two field seasons (1974 and 1975). A total of five species was detected within intensive study areas. These included the Great Basin pocket mouse (Perognathus parvus), deer mouse (Peromyscus maniculatus), northern grasshopper mouse (Onychomys leucogaster), sagebrush vole (Lagurus curtatus), and western harvest mouse (Reithrodontomys megalotis). These species are probably representative of those found throughout the area at this particular elevation. Townsends ground squirrel (Spermophilus townsendii) also occurs in this area but did not occur on the sampling plots during the study duration. The pocket mouse was the only species present in sufficient numbers to permit a detailed analysis of population parameters. A discussion concerning the role small mammals play in mineral cycling and energy transfer processes is included along with a diagram depicting food web interrelationships for consumers inhabiting the 200 Area plateau region. Estimates of small mammal density and biomass provided in this document are needed for an overall understanding of the role biota play in the transfer of waste nuclides

Small-scale barriers mitigate desertification processes and enhance plant recruitment in a degraded semiarid grassland

Science.gov (United States)

Fick, Stephen E; Decker, Cheryl E.; Duniway, Michael C.; Miller, Mark E.

2016-01-01

Anthropogenic desertification is a problem that plagues drylands globally; however, the factors which maintain degraded states are often unclear. In Canyonlands National Park on the Colorado Plateau of southeastern Utah, many degraded grasslands have not recovered structure and function >40 yr after release from livestock grazing pressure, necessitating active restoration. We hypothesized that multiple factors contribute to the persistent degraded state, including lack of seed availability, surficial soil-hydrological properties, and high levels of spatial connectivity (lack of perennial vegetation and other surface structure to retain water, litter, seed, and sediment). In combination with seeding and surface raking treatments, we tested the effect of small barrier structures (“ConMods”) designed to disrupt the loss of litter, seed and sediment in degraded soil patches within the park. Grass establishment was highest when all treatments (structures, seed addition, and soil disturbance) were combined, but only in the second year after installation, following favorable climatic conditions. We suggest that multiple limiting factors were ameliorated by treatments, including seed limitation and microsite availability, seed removal by harvester ants, and stressful abiotic conditions. Higher densities of grass seedlings on the north and east sides of barrier structures following the summer months suggest that structures may have functioned as artificial “nurse-plants”, sheltering seedlings from wind and radiation as well as accumulating wind-blown resources. Barrier structures increased the establishment of both native perennial grasses and exotic annuals, although there were species-specific differences in mortality related to spatial distribution of seedlings within barrier structures. The unique success of all treatments combined, and even then only under favorable climatic conditions and in certain soil patches, highlights that restoration success (and

Some concepts in the management and control of small mammal populations

International Nuclear Information System (INIS)

Wagner, F.H.

1978-01-01

This review discusses some broadly ecological aspects of small mammal management and some positive values of their populations. Although small mammals consume a minor fraction of the total primary production in terrestrial ecosystems, they may by preferential feeding on a few plant species suppress those species within a community. The overall lifeform of the vegetation may not be changed. In cases where severe disturbance (e.g., grazing) reduces climax vegetation (e.g., grasses), and these are replaced by seral species of a different life form (e.g., shrubs), the vegetation may be held in a seral stage by heavy, small mammal pressure on the now subdominant, climax species. They may thus maintain a different vegetation life form than would exist in the absence of their pressure, and restoration of a near-climax state may depend on intensive control. There is a large accumulation of information on small mammal species composition and densities in different vegetation types. Some of it discusses the mechanisms which relate these densities to the habitat. If this information were compiled and generalized, it would provide a basis for predicting the impact on small mammal populations of contemplated land-use programs and possible small mammal management, either control or enhancement, through vegetation manipulation. There is considerable evidence that prey abundance is an important determinant of predator densities. Concern for predator conservation needs to consider abundance of prey species and the factors which affect it

Effect of wild-type Shigella species and attenuated Shigella vaccine candidates on small intestinal barrier function, antigen trafficking, and cytokine release.

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Maria Fiorentino

Full Text Available Bacterial dysentery due to Shigella species is a major cause of morbidity and mortality worldwide. The pathogenesis of Shigella is based on the bacteria's ability to invade and replicate within the colonic epithelium, resulting in severe intestinal inflammatory response and epithelial destruction. Although the mechanisms of pathogenesis of Shigella in the colon have been extensively studied, little is known on the effect of wild-type Shigella on the small intestine and the role of the host response in the development of the disease. Moreover, to the best of our knowledge no studies have described the effects of apically administered Shigella flexneri 2a and S. dysenteriae 1 vaccine strains on human small intestinal enterocytes. The aim of this study was to assess the coordinated functional and immunological human epithelial responses evoked by strains of Shigella and candidate vaccines on small intestinal enterocytes. To model the interactions of Shigella with the intestinal mucosa, we apically exposed monolayers of human intestinal Caco2 cells to increasing bacterial inocula. We monitored changes in paracellular permeability, examined the organization of tight-junctions and the pro-inflammatory response of epithelial cells. Shigella infection of Caco2 monolayers caused severe mucosal damage, apparent as a drastic increase in paracellular permeability and disruption of tight junctions at the cell-cell boundary. Secretion of pro-inflammatory IL-8 was independent of epithelial barrier dysfunction. Shigella vaccine strains elicited a pro-inflammatory response without affecting the intestinal barrier integrity. Our data show that wild-type Shigella infection causes a severe alteration of the barrier function of a small intestinal cell monolayer (a proxy for mucosa and might contribute (along with enterotoxins to the induction of watery diarrhea. Diarrhea may be a mechanism by which the host attempts to eliminate harmful bacteria and transport them

Overcoming barriers to engaging socio-economically disadvantaged populations in CHD primary prevention: a qualitative study

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Cunningham Heather

2010-07-01

Full Text Available Abstract Background Preventative medicine has become increasingly important in efforts to reduce the burden of chronic disease in industrialised countries. However, interventions that fail to recruit socio-economically representative samples may widen existing health inequalities. This paper explores the barriers and facilitators to engaging a socio-economically disadvantaged (SED population in primary prevention for coronary heart disease (CHD. Methods The primary prevention element of Have a Heart Paisley (HaHP offered risk screening to all eligible individuals. The programme employed two approaches to engaging with the community: a a social marketing campaign and b a community development project adopting primarily face-to-face canvassing. Individuals living in areas of SED were under-recruited via the social marketing approach, but successfully recruited via face-to-face canvassing. This paper reports on focus group discussions with participants, exploring their perceptions about and experiences of both approaches. Results Various reasons were identified for low uptake of risk screening amongst individuals living in areas of high SED in response to the social marketing campaign and a number of ways in which the face-to-face canvassing approach overcame these barriers were identified. These have been categorised into four main themes: (1 processes of engagement; (2 issues of understanding; (3 design of the screening service and (4 the priority accorded to screening. The most immediate barriers to recruitment were the invitation letter, which often failed to reach its target, and the general distrust of postal correspondence. In contrast, participants were positive about the face-to-face canvassing approach. Participants expressed a lack of knowledge and understanding about CHD and their risk of developing it and felt there was a lack of clarity in the information provided in the mailing in terms of the process and value of screening. In

The effects of Lactobacillus plantarum on small intestinal barrier function and mucosal gene transcription; A randomized double-blind placebo controlled trial

NARCIS (Netherlands)

Mujagic, Zlatan; Vos, De Paul; Boekschoten, Mark V.; Govers, Coen; Pieters, Harm J.H.M.; Wit, De Nicole J.W.; Bron, Peter A.; Masclee, Ad A.M.; Troost, Freddy J.

2017-01-01

The aim of this study was to investigate the effects of three Lactobacillus plantarum strains on in-vivo small intestinal barrier function and gut mucosal gene transcription in human subjects. The strains were selected for their differential effects on TLR signalling and tight junction protein

The effects of Lactobacillus plantarum on small intestinal barrier function and mucosal gene transcription; a randomized double-blind placebo controlled trial

NARCIS (Netherlands)

Mujagic, Zlatan; Vos, de Paul; Boekschoten, Mark; Govers, Coen; Pieters, Harm J.H.M.; Wit, de Nicole; Bron, Peter A.; Masclee, Ad A.M.; Troost, Freddy J.

2017-01-01

The aim of this study was to investigate the effects of three Lactobacillus plantarum strains on in-vivo small intestinal barrier function and gene transcription in human subjects. The strains were selected for their differential effects on TLR signalling and tight junction protein rearrangement,

The effects of Lactobacillus plantarum on small intestinal barrier function and mucosal gene transcription; a randomized double-blind placebo controlled trial

NARCIS (Netherlands)

Mujagic, Zlatan; de Vos, Paul; Boekschoten, Mark V.; Govers, Coen; Pieters, Harm-Jan H M; de Wit, Nicole J. W.; Bron, Peter A.; Masclee, Ad A M; Troost, Freddy J

2017-01-01

The aim of this study was to investigate the effects of three Lactobacillus plantarum strains on in-vivo small intestinal barrier function and gut mucosal gene transcription in human subjects. The strains were selected for their differential effects on TLR signalling and tight junction protein

A study of small, medium, and micro-sized enterprise (SMME business owner and stakeholder perceptions of barriers and enablers in the South African retail sector

Directory of Open Access Journals (Sweden)

Mlenga G Jere

2015-11-01

Full Text Available Despite the support extended to the small business sector in South Africa, the growth and survival rates of small, medium, and micro-sized enterprises (SMMEs are lower than expected. This paper investigates business owner and stakeholder perceptions of barriers and enablers of the start-up, survival, and growth of SMMEs in the South African retail sector. A qualitative research design using semi-structured interviews was employed for data collection from samples of stakeholders and business owners. Framework analysis was used to analyse both sets of data. The findings show that the stakeholders and business owners consider the lack of support, competition, skills shortages, and poor internal controls as the key barriers to the start-up, survival, and growth of SMMEs. Stakeholders considered the business environment as the key enabler while the business owners regarded increasing demand as the key enabler. To address the barriers, recommendations relating to skills development, funding, shelter and services, and other business development resources are presented

Natural and sexual selection giveth and taketh away reproductive barriers: models of population divergence in guppies.

Science.gov (United States)

Labonne, Jacques; Hendry, Andrew P

2010-07-01

The standard predictions of ecological speciation might be nuanced by the interaction between natural and sexual selection. We investigated this hypothesis with an individual-based model tailored to the biology of guppies (Poecilia reticulata). We specifically modeled the situation where a high-predation population below a waterfall colonizes a low-predation population above a waterfall. Focusing on the evolution of male color, we confirm that divergent selection causes the appreciable evolution of male color within 20 generations. The rate and magnitude of this divergence were reduced when dispersal rates were high and when female choice did not differ between environments. Adaptive divergence was always coupled to the evolution of two reproductive barriers: viability selection against immigrants and hybrids. Different types of sexual selection, however, led to contrasting results for another potential reproductive barrier: mating success of immigrants. In some cases, the effects of natural and sexual selection offset each other, leading to no overall reproductive isolation despite strong adaptive divergence. Sexual selection acting through female choice can thus strongly modify the effects of divergent natural selection and thereby alter the standard predictions of ecological speciation. We also found that under no circumstances did divergent selection cause appreciable divergence in neutral genetic markers.

ORDEM2010 and MASTER-2009 Modeled Small Debris Population Comparison

Science.gov (United States)

Krisko, Paula H.; Flegel, S.

2010-01-01

The latest versions of the two premier orbital debris engineering models, NASA s ORDEM2010 and ESA s MASTER-2009, have been publicly released. Both models have gone through significant advancements since inception, and now represent the state-of-the-art in orbital debris knowledge of their respective agencies. The purpose of these models is to provide satellite designers/operators and debris researchers with reliable estimates of the artificial debris environment in near-Earth orbit. The small debris environment within the size range of 1 mm to 1 cm is of particular interest to both human and robotic spacecraft programs. These objects are much more numerous than larger trackable debris but are still large enough to cause significant, if not catastrophic, damage to spacecraft upon impact. They are also small enough to elude routine detection by existing observation systems (radar and telescope). Without reliable detection the modeling of these populations has always coupled theoretical origins with supporting observational data in different degrees. This paper details the 1 mm to 1 cm orbital debris populations of both ORDEM2010 and MASTER-2009; their sources (both known and presumed), current supporting data and theory, and methods of population analysis. Fluxes on spacecraft for chosen orbits are also presented and discussed within the context of each model.

The Phylogeography and Population Demography of the Yunnan Caecilian (Ichthyophis bannanicus: Massive Rivers as Barriers to Gene Flow.

Directory of Open Access Journals (Sweden)

Hui Wang

Full Text Available Ichthyophis bannanicus is the only caecilian species in China. In this study, the phylogeography and population demography of I. bannanicus were explored, based on the mitochondrial DNA genes (cyt b and ND2 and 15 polymorphic microsatellite loci. Altogether 158 individuals were collected from five populations in Yunnan province, Guangxi province, Guangdong province, and Northern Vietnam. Phylogeographical and population structure analysis identified either two groups (Xishuangbanna, Northern Vietnam-Yulin-Yangchun-Deqing or three groups (Xishuangbanna, Northern Vietnam-Yulin-Yangchun, and Deqing, indicating that the Red River and Pearl River systems may have acted as gene-flow barriers for I. bannanicus. Historical population expansion that happened 15-17 Ka ago was detected for mtDNA data and was possibly triggered by warmer weather after the Last Glacial Maximum. However, the Bayesian simulations of population history based on microsatellite data pinpointed population decline in all populations since 19,123 to 1,029 years ago, demonstrating a significant influence of anthropogenic habitat alteration on I. bannanicus.

Barriers to energy efficiency improvement. Empirical evidence from small-and-medium-sized enterprises in China

Energy Technology Data Exchange (ETDEWEB)

Kostka, Genia; Moslener, Ulf; Andreas, Jan G.

2012-07-01

This paper analyzes barriers for energy efficiency investments for small-and medium-sized enterprises (SMEs) in China. Based on a survey of 480 SMEs in Zhejiang Province, this study assesses financial, informational, and organizational barriers for energy efficiency investments in the SME sector. The conventional view has been that the lack of appropriate financing mechanisms particularly hinders SMEs to adopt cost-effective energy efficiency measures. As such, closing the financing gap for SMEs is seen as a prerequisite in order to promote energy efficiency in the sector. The econometric estimates of this study, however, suggest that access to information is an important determinant of investment outcomes, while this is less clear with respect to financial and organizational factors. More than 40 percent of enterprises in the sample declared that that they are not aware of energy saving equipments or practices in their respective business area, indicating that there are high transaction costs for SMEs to gather, assess, and apply information about energy saving potentials and relevant technologies. One implication is that the Chinese government may assume an active role in fostering the dissemination of energy-efficiency related information in the SME sector. (orig.)

Breakdown of mucin as barrier to digestive enzymes in the ischemic rat small intestine.

Directory of Open Access Journals (Sweden)

Marisol Chang

Full Text Available Loss of integrity of the epithelial/mucosal barrier in the small intestine has been associated with different pathologies that originate and/or develop in the gastrointestinal tract. We showed recently that mucin, the main protein in the mucus layer, is disrupted during early periods of intestinal ischemia. This event is accompanied by entry of pancreatic digestive enzymes into the intestinal wall. We hypothesize that the mucin-containing mucus layer is the main barrier preventing digestive enzymes from contacting the epithelium. Mucin breakdown may render the epithelium accessible to pancreatic enzymes, causing its disruption and increased permeability. The objective of this study was to investigate the role of mucin as a protection for epithelial integrity and function. A rat model of 30 min splanchnic arterial occlusion (SAO was used to study the degradation of two mucin isoforms (mucin 2 and 13 and two epithelial membrane proteins (E-cadherin and toll-like receptor 4, TLR4. In addition, the role of digestive enzymes in mucin breakdown was assessed in this model by luminal inhibition with acarbose, tranexamic acid, or nafamostat mesilate. Furthermore, the protective effect of the mucin layer against trypsin-mediated disruption of the intestinal epithelium was studied in vitro. Rats after SAO showed degradation of mucin 2 and fragmentation of mucin 13, which was not prevented by protease inhibition. Mucin breakdown was accompanied by increased intestinal permeability to FITC-dextran as well as degradation of E-cadherin and TLR4. Addition of mucin to intestinal epithelial cells in vitro protected against trypsin-mediated degradation of E-cadherin and TLR4 and reduced permeability of FITC-dextran across the monolayer. These results indicate that mucin plays an important role in the preservation of the mucosal barrier and that ischemia but not digestive enzymes disturbs mucin integrity, while digestive enzymes actively mediate epithelial cell

Numerical simulation of flood barriers

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Srb, Pavel; Petrů, Michal; Kulhavý, Petr

This paper deals with testing and numerical simulating of flood barriers. The Czech Republic has been hit by several very devastating floods in past years. These floods caused several dozens of causalities and property damage reached billions of Euros. The development of flood measures is very important, especially for the reduction the number of casualties and the amount of property damage. The aim of flood control measures is the detention of water outside populated areas and drainage of water from populated areas as soon as possible. For new flood barrier design it is very important to know its behaviour in case of a real flood. During the development of the barrier several standardized tests have to be carried out. Based on the results from these tests numerical simulation was compiled using Abaqus software and some analyses were carried out. Based on these numerical simulations it will be possible to predict the behaviour of barriers and thus improve their design.

Life cycle ecophysiology of small pelagic fish and climate-driven changes in populations

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Peck, Myron A.; Reglero, Patricia; Takahashi, Motomitsu; Catalán, Ignacio A.

2013-09-01

Due to their population characteristics and trophodynamic role, small pelagic fishes are excellent bio-indicators of climate-driven changes in marine systems world-wide. We argue that making robust projections of future changes in the productivity and distribution of small pelagics will require a cause-and-effect understanding of historical changes based upon physiological principles. Here, we reviewed the ecophysiology of small pelagic (clupeiform) fishes including a matrix of abiotic and biotic extrinsic factors (e.g., temperature, salinity, light, and prey characteristics) and stage-specific vital rates: (1) adult spawning, (2) survival and development of eggs and yolk sac larvae, and (3) feeding and growth of larvae, post-larvae and juveniles. Emphasis was placed on species inhabiting Northwest Pacific and Northeast Atlantic (European) waters for which summary papers are particularly scarce compared to anchovy and sardine in upwelling systems. Our review revealed that thermal niches (optimal and sub-optimal ranges in temperatures) were species- and stage-specific but that temperature effects only partly explained observed changes in the distribution and/or productivity of populations in the Northwest Pacific and Northeast Atlantic; changes in temperature may be necessary but not sufficient to induce population-level shifts. Prey availability during the late larval and early juvenile period was a common, density-dependent mechanism linked to fluctuations in populations but recruitment mechanisms were system-specific suggesting that generalizations of climate drivers across systems should be avoided. We identified gaps in knowledge regarding basic elements of the growth physiology of each life stage that will require additional field and laboratory study. Avenues of research are recommended that will aid the development of models that provide more robust, physiological-based projections of the population dynamics of these and other small pelagic fish. In our

SMEs and Barriers to Skill Development: A Scottish Perspective.

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Lange, Thomas; Ottens, Melanie; Taylor, Andrea

2000-01-01

Analysis of Scottish small and medium-sized enterprises reveals that small business culture is a significant barrier to skill development. Other barriers include awareness, finance, and access to training. A welter of recent policy initiatives has added to a state of confusion about the role of training. (SK)

Experimental evidence for convergent evolution of maternal care heuristics in industrialized and small-scale populations.

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Kushnick, Geoff; Hanowell, Ben; Kim, Jun-Hong; Langstieh, Banrida; Magnano, Vittorio; Oláh, Katalin

2015-06-01

Maternal care decision rules should evolve responsiveness to factors impinging on the fitness pay-offs of care. Because the caretaking environments common in industrialized and small-scale societies vary in predictable ways, we hypothesize that heuristics guiding maternal behaviour will also differ between these two types of populations. We used a factorial vignette experiment to elicit third-party judgements about likely caretaking decisions of a hypothetical mother and her child when various fitness-relevant factors (maternal age and access to resources, and offspring age, sex and quality) were varied systematically in seven populations-three industrialized and four small-scale. Despite considerable variation in responses, we found that three of five main effects, and the two severity effects, exhibited statistically significant industrialized/ small-scale population differences. All differences could be explained as adaptive solutions to industrialized versus small-scale caretaking environments. Further, we found gradients in the relationship between the population-specific estimates and national-level socio-economic indicators, further implicating important aspects of the variation in industrialized and small-scale caretaking environments in shaping heuristics. Although there is mounting evidence for a genetic component to human maternal behaviour, there is no current evidence for interpopulation variation in candidate genes. We nonetheless suggest that heuristics guiding maternal behaviour in diverse societies emerge via convergent evolution in response to similar selective pressures.

Barriers to Business Model Innovation in Swedish Agriculture

Directory of Open Access Journals (Sweden)

Olof Sivertsson

2015-02-01

Full Text Available Swedish agricultural companies, especially small farms, are struggling to be profitable in difficult economic times. It is a challenge for Swedish farmers to compete with imported products on prices. The agricultural industry, however, supports the view that through business model innovation, farms can increase their competitive advantage. This paper identifies and describes some of the barriers Swedish small farms encounter when they consider business model innovation. A qualitative approach is used in the study. Agriculture business consultants were interviewed. In a focus group led by the researchers, farmers discussed business model innovation, including the exogenous and endogenous barriers to such innovation. The paper concludes many barriers exist when farmers consider innovation of agricultural business models. Some barriers are caused by human factors, such as individuals’ attitudes, histories, and traditions. Other barriers are more contextual in nature and relate to a particular industry or company setting. Still other barriers, such as government regulations, value chain position, and weather, are more abstract. All barriers, however, merit attention when Swedish agricultural companies develop new business models.

Social Security Measures for Elderly Population in Delhi, India: Awareness, Utilization and Barriers.

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Kohli, Charu; Gupta, Kalika; Banerjee, Bratati; Ingle, Gopal Krishna

2017-05-01

World population of elderly is increasing at a fast pace. The number of elderly in India has increased by 54.77% in the last 15 years. A number of social security measures have been taken by Indian government. To assess awareness, utilization and barriers faced while utilizing social security schemes by elderly in a secondary care hospital situated in a rural area in Delhi, India. A cross-sectional study was conducted among 360 individuals aged 60 years and above in a secondary care hospital situated in a rural area in Delhi. A pre-tested, semi-structured schedule prepared in local language was used. Data was analysed using SPSS software (version 17.0). Chi-square test was used to observe any statistical association between categorical variables. The results were considered statistically significant if p-value was less than 0.05. A majority of study subjects were females (54.2%), Hindu (89.7%), married (60.3%) and were not engaged in any occupation (82.8%). Awareness about Indira Gandhi National Old Age Pension Scheme (IGNOAPS) was present among 286 (79.4%) and Annapurna scheme in 193 (53.6%) subjects. Among 223 subjects who were below poverty line, 179 (80.3%) were aware of IGNOAPS; while, 112 (50.2%) were utilizing the scheme. There was no association of awareness with education status, occupation, religion, family type, marital status and caste (p>0.05). Corruption and tedious administrative formalities were major barriers reported. Awareness generation, provision of information on how to approach the concerned authority for utilizing the scheme and ease of administrative procedures should be an integral part of any social security scheme or measure. In the present study, about 79.4% of elderly were aware and 45% of the eligible subjects were utilizing pension scheme. Major barriers reported in utilization of schemes were corruption and tedious administrative procedures.

Heavy Cigarette Smokers in a Chinese Population Display a Compromised Permeability Barrier

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Xin, Shujun; Ye, Li; Lv, Chengzhi; Elias, Peter M.

2016-01-01

Cigarette smoking is associated with various cutaneous disorders with defective permeability. Yet, whether cigarette smoking influences epidermal permeability barrier function is largely unknown. Here, we measured skin biophysical properties, including permeability barrier homeostasis, stratum corneum (SC) integrity, SC hydration, skin surface pH, and skin melanin/erythema index, in cigarette smokers. A total of 99 male volunteers were enrolled in this study. Smokers were categorized as light-to-moderate (hydration and skin melanin/erythema index on the dorsal hand, forehead, and cheek. Basal transepidermal water loss (TEWL) and barrier recovery rates were assessed on the forearm. A Skin-pH-Meter pH900 was used to measure skin surface pH. Our results showed that heavy cigarette smokers exhibited delayed barrier recovery after acute abrogation (1.02% ± 13.06 versus 16.48% ± 6.07), and barrier recovery rates correlated negatively with the number of daily cigarettes consumption (p = 0.0087). Changes in biophysical parameters in cigarette smokers varied with body sites. In conclusion, heavy cigarette smokers display compromised permeability barrier homeostasis, which could contribute, in part, to the increased prevalence of certain cutaneous disorders characterized by defective permeability. Thus, improving epidermal permeability barrier should be considered for heavy cigarette smokers. PMID:27437403

Clinical research in small genomically stratified patient populations.

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Martin-Liberal, J; Rodon, J

2017-07-01

The paradigm of early drug development in cancer is shifting from 'histology-oriented' to 'molecularly oriented' clinical trials. This change can be attributed to the vast amount of tumour biology knowledge generated by large international research initiatives such as The Cancer Genome Atlas (TCGA) and the use of next generation sequencing (NGS) techniques developed in recent years. However, targeting infrequent molecular alterations entails a series of special challenges. The optimal molecular profiling method, the lack of standardised biological thresholds, inter- and intra-tumor heterogeneity, availability of enough tumour material, correct clinical trials design, attrition rate, logistics or costs are only some of the issues that need to be taken into consideration in clinical research in small genomically stratified patient populations. This article examines the most relevant challenges inherent to clinical research in these populations. Moreover, perspectives from the Academia point of view are reviewed as well as initiatives to be taken in forthcoming years. Copyright © 2017 Elsevier Ltd. All rights reserved.

Small wind turbine energy policies for residential and small business usage in Ontario, Canada

International Nuclear Information System (INIS)

Heagle, A.L.B.; Naterer, G.F.; Pope, K.

2011-01-01

This paper examines the social barriers, policies, and incentive programs for residential and small business small wind (RBSW) projects, particularly in Ontario, Canada, as well as comparisons with California, US, and the United Kingdom. The alignment between socio-political and community acceptance is considered for its impact on market acceptance of the technology. Barriers inhibiting social acceptance of RBSW projects include adequate capacity factor, cost effectiveness, wind variability, audio-esthetics impact, health and safety, procedural fairness, and transparency. A review of the policies for implementation of small wind projects in each location is presented. Strategies to overcome barriers to social acceptance are examined, along with recommendations for the increased implementation of RBSW projects worldwide. Recommendations to increase social acceptance and subsequent implementation of RBSW projects include the collaboration of government agencies, industry and community members, during RBSW implementation processes, and the provision of consistent, long-term, supportive policies and incentive programs for project owners. - Highlights: → This paper examines the social barriers, policies, and incentive programs for residential and small business small wind (RBSW) projects, particularly in Ontario, Canada, as well as comparisons with California, US, and the United Kingdom. → Barriers inhibiting social acceptance of RBSW projects include adequate capacity factor, cost effectiveness, wind variability, audio-esthetics impact, health and safety, procedural fairness, and transparency. → Recommendations to increase social acceptance and subsequent implementation of RBSW projects include the collaboration of government agencies, industry and community members, during RBSW implementation processes, and the provision of consistent, long-term, supportive policies and incentive programs for project owners.

Defining a target population at high risk of long-term foster care: barriers to permanency for families of children with serious emotional disturbances.

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Akin, Becci A; Bryson, Stephanie A; McDonald, Tom; Walker, Sheila

2012-01-01

Long-term foster care (LTFC) is an enduring problem that lacks evidence of effective strategies for practice or policy. This article describes initial activities of a statewide project of the national Permanency Innovations Initiative. The authors sought to: (1) verify the relevance of children's mental health as a predictor of LTFC, (2) describe critical barriers encountered by parents of children with serious emotional disturbances, and (3) identify systems barriers that hinder permanency for this target population.

Post-dam vegetation changes and small mammal populations in the Peace-Athabasca delta

International Nuclear Information System (INIS)

Pfister, O.

1993-01-01

Research aimed at monitoring wildlife populations is a useful way to estimate the impact and consequences of hydroelectric projects on northern deltas. Such studies could provide valuable insights on the potential effect of the drying of deltas in the context of global climate change. The Peace-Athabasca River Delta, one of the most extensive northern inland deltas in the western hemisphere, represents a unique site to study such effects. Construction of the Bennett Dam in 1968 has had serious effects on the delta's ecological integrity; the resulting lower water levels and colonization of grass meadow communities by willows and the movement of shorelines has affected wildlife distribution and population levels. A study was conducted to estimate the impact of the invasion of grass meadows by willows on small rodent populations in the delta. Live trapping grids were established at three sites. Population estimates were obtained by the minimum number known method and used to calculate biomass of small mammals in willow and meadow grids. Mean trapping estimates (MTEs) of adult meadow voles ranged from under 1 per hectare on willow grids to 28 per hectare on meadow grids. On willow grids only, MTEs for adult populations of deer mice, red-backed voles, and meadow jumping mice reached 6, 6, and less than 1 per hectare respectively. It is estimated that the development of grass meadows into willow shrublands over the next 20-40 y could result in a loss of over 50% of the biomass of small rodents present in 1976. This should have a negative effect on the foraging efficiency and productivity of secondary consumers such as weasel and owl. 109 refs., 16 figs., 29 tabs

Reproductive isolation among allopatric Drosophila montana populations.

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Jennings, Jackson H; Snook, Rhonda R; Hoikkala, Anneli

2014-11-01

An outstanding goal in speciation research is to trace the mode and tempo of the evolution of barriers to gene flow. Such research benefits from studying incipient speciation, in which speciation between populations has not yet occurred, but where multiple potential mechanisms of reproductive isolation (RI: i.e., premating, postmating-prezygotic (PMPZ), and postzygotic barriers) may act. We used such a system to investigate these barriers among allopatric populations of Drosophila montana. In all heteropopulation crosses we found premating (sexual) isolation, which was either symmetric or asymmetric depending on the population pair compared. Postmating isolation was particularly strong in crosses involving males from one of the study populations, and while sperm were successfully transferred, stored, and motile, we experimentally demonstrated that the majority of eggs produced were unfertilized. Thus, we identified the nature of a PMPZ incompatibility. There was no evidence of intrinsic postzygotic effects. Measures of absolute and relative strengths of pre- and postmating barriers showed that populations differed in the mode and magnitude of RI barriers. Our results indicate that incipient RI among populations can be driven by different contributions of both premating and PMPZ barriers occurring between different population pairs and without the evolution of postzygotic barriers. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Services for people with communication disability in Fiji: barriers and drivers of change.

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Hopf, Suzanne C; McLeod, Sharynne

2015-01-01

The World Health Organization's World report on disability calls upon all nations to 'remove the barriers which prevent [people with disabilities] from participating in their communities; getting a quality education, finding decent work, and having their voices heard' (p. 5). People with communication disability (PWCD), as a consequence of their atypical communication, may be more likely to be excluded from society, and denied their basic human rights, than other people with disability. Fiji, a multicultural and multilingual nation in the south-western Pacific Ocean, has limited services for PWCD. Service providers in Fiji include disability care workers, special education teachers, traditional healers, and a small number of visiting volunteer speech-language pathologists. This paper outlines the historical and current barriers to, and drivers of change for, service development for PWCD in Fiji. Five barriers to service development for PWCD in Fiji were identified. (1) A major structural barrier is the small population size to develop appropriate infrastructure including professional education programs. (2) Geographical barriers include the dispersed geography across 300 islands, low population density, the rural-urban divide, and risk of disaster from cyclones and flooding. (3) Linguistic diversity, while culturally important, can present a barrier to the provision of quality services that are available in the languages spoken by PWCD. (4) Cultural barriers include historical political instability, although Fiji has become more stable due to the recent democratic elections. The social climate affects development of services that are appropriate for different dominant cultural groups. (5) Financial barriers include low gross domestic product, low financial security and low human development index; however, the financial outlook for Fiji is steadily improving due to the change in political stability. Three levels of drivers of change were identified. Macro

The Effect of Multiple Paternity on Genetic Diversity of Small Populations during and after Colonisation

KAUST Repository

Rafajlović, Marina; Eriksson, Anders; Rimark, Anna; Hintz-Saltin, Sara; Charrier, Gré gory; Panova, Marina; André , Carl; Johannesson, Kerstin; Mehlig, Bernhard

2013-01-01

Genetic variation within and among populations is influenced by the genetic content of the founders and the migrants following establishment. This is particularly true if populations are small, migration rate low and habitats arranged in a stepping

Role of women in population.

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Srivasdava, T N

Population control through voluntary adoption of family planning is emphasized in India's family planning policy. The 1981 census figures have not shown an arresting rate of population growth. The social and attitudinal barriers to promoting the concept of the small family are great where men and women are not exposed to new ideas. The target groups for family planning include the 75% of the population residing in rural areas. The literacy rate for women in rural areas in 1971 was 18.69. Motivation is difficult unless supported by systematic education. Women play an important role in the determination of family size. Participation in social and economic activities may help to promote small family size by meeting the necessary conditions of emotional and social fulfillment of women outside the family context. Adquate education for women in rural as well as urban areas can elucidate alternatives to childbearing and enable women to appreciate the need for and use of contraception. Employment opportunities enhance women's familial decision making power through the acquisition of an alternative social and economic role, which may help them to adopt birth control practices, space their children, and limit family size. Motivational schemes may change the attitudes of a small number of families, however, greater gains could be achieved through an investment in women's education and employment.

13 CFR 120.175 - Coastal barrier islands.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Coastal barrier islands. 120.175 Section 120.175 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Policies Applying to All Business Loans Requirements Imposed Under Other Laws and Orders § 120.175 Coastal barrier...

Lessons learned from IDeAl - 33 recommendations from the IDeAl-net about design and analysis of small population clinical trials.

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Hilgers, Ralf-Dieter; Bogdan, Malgorzata; Burman, Carl-Fredrik; Dette, Holger; Karlsson, Mats; König, Franz; Male, Christoph; Mentré, France; Molenberghs, Geert; Senn, Stephen

2018-05-11

IDeAl (Integrated designs and analysis of small population clinical trials) is an EU funded project developing new statistical design and analysis methodologies for clinical trials in small population groups. Here we provide an overview of IDeAl findings and give recommendations to applied researchers. The description of the findings is broken down by the nine scientific IDeAl work packages and summarizes results from the project's more than 60 publications to date in peer reviewed journals. In addition, we applied text mining to evaluate the publications and the IDeAl work packages' output in relation to the design and analysis terms derived from in the IRDiRC task force report on small population clinical trials. The results are summarized, describing the developments from an applied viewpoint. The main result presented here are 33 practical recommendations drawn from the work, giving researchers a comprehensive guidance to the improved methodology. In particular, the findings will help design and analyse efficient clinical trials in rare diseases with limited number of patients available. We developed a network representation relating the hot topics developed by the IRDiRC task force on small population clinical trials to IDeAl's work as well as relating important methodologies by IDeAl's definition necessary to consider in design and analysis of small-population clinical trials. These network representation establish a new perspective on design and analysis of small-population clinical trials. IDeAl has provided a huge number of options to refine the statistical methodology for small-population clinical trials from various perspectives. A total of 33 recommendations developed and related to the work packages help the researcher to design small population clinical trial. The route to improvements is displayed in IDeAl-network representing important statistical methodological skills necessary to design and analysis of small-population clinical trials. The methods

Effects of alanyl-glutamine supplementation on the small intestinal mucosa barrier in weaned piglets

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Shen Xing

2017-02-01

Full Text Available Objective The study was to investigate the effects of alanyl-glutamine (Ala-Gln and glutamine (Gln supplementation on the intestinal mucosa barrier in piglets. Methods A total of 180 barrows with initial weight 10.01±0.03 kg were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala], Ala-Gln diet (0.5% Ala-Gln, Gln diet (0.34% Gln and 0.21% Ala, respectively. Results The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p<0.05, Gln supplementation increased the villi height of jejunum (p<0.05, Ala-Gln supplementation up-regulated the mRNA expressions of epidermal growth factor receptor and insulin-like growth factor 1 receptor in jejunal mucosa (p<0.05, raised the mRNA expressions of Claudin-1, Occludin, zonula occludens protein-1 (ZO-1 and the protein levels of Occludin, ZO-1 in jejunal mucosa (p<0.05, Ala-Gln supplementation enlarged the number of goblet cells in duodenal and ileal epithelium (p<0.05, Gln increased the number of goblet cells in duodenal epithelium (p<0.05 and Ala-Gln supplementation improved the concentrations of secretory immunoglobulin A and immunoglobulin G in the jejunal mucosa (p<0.05. Conclusion These results demonstrated that dietary Ala-Gln supplementation could maintain the integrity of small intestine and promote the functions of intestinal mucosa barriers in piglets.

Significant genetic differentiation within the population of the Island of Corsica (France) revealed by y-chromosome analysis.

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Ghiani, Maria Elena; Varesi, Laurent; Mitchell, Robert John; Vona, Giuseppe

2009-12-01

Using 10 Y-chromosome short tandem repeat allelic and haplotypic frequencies, we examined genetic variation within the population of Corsica and its relationship with other Mediterranean populations. The most significant finding is the high level of genetic differentiation within Corsica, with strong evidence of an effective barrier to male-mediated gene flow between the south and the rest of the island. This internal differentiation most probably results from low exogamy among small isolated populations and also from the orography of the island, with a central mountain chain running the length of the island restricting human movement. This physical barrier is reflected not only in present-day intraisland linguistic and genetic differences but also in the relatedness of Corsican regions to other Mediterranean groups. Northwest and Central Corsica are much closer to West Mediterranean populations, whereas South Corsica is closer to Central-North Sardinia and East Mediterranean populations.

Invasion versus isolation: trade-offs in managing native salmonids with barriers to upstream movement.

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Fausch, Kurt D; Rieman, Bruce E; Dunham, Jason B; Young, Michael K; Peterson, Douglas P

2009-08-01

Conservation biologists often face the trade-off that increasing connectivity in fragmented landscapes to reduce extinction risk of native species can foster invasion by non-native species that enter via the corridors created, which can then increase extinction risk. This dilemma is acute for stream fishes, especially native salmonids, because their populations are frequently relegated to fragments of headwater habitat threatened by invasion from downstream by 3 cosmopolitan non-native salmonids. Managers often block these upstream invasions with movement barriers, but isolation of native salmonids in small headwater streams can increase the threat of local extinction. We propose a conceptual framework to address this worldwide problem that focuses on 4 main questions. First, are populations of conservation value present (considering evolutionary legacies, ecological functions, and socioeconomic benefits as distinct values)? Second, are populations vulnerable to invasion and displacement by non-native salmonids? Third, would these populations be threatened with local extinction if isolated with barriers? And, fourth, how should management be prioritized among multiple populations? We also developed a conceptual model of the joint trade-off of invasion and isolation threats that considers the opportunities for managers to make strategic decisions. We illustrated use of this framework in an analysis of the invasion-isolation trade-off for native cutthroat trout (Oncorhynchus clarkii) in 2 contrasting basins in western North America where invasion and isolation are either present and strong or farther away and apparently weak. These cases demonstrate that decisions to install or remove barriers to conserve native salmonids are often complex and depend on conservation values, environmental context (which influences the threat of invasion and isolation), and additional socioeconomic factors. Explicit analysis with tools such as those we propose can help managers make

Ancient geographical barriers drive differentiation among Sonneratia caseolaris populations and recent divergence from S. lanceolata

Directory of Open Access Journals (Sweden)

Yuchen Yang

2016-10-01

Full Text Available Glacial vicariance is thought to influence population dynamics and speciation of many marine organisms. Mangroves, a plant group inhabiting intertidal zones, were also profoundly influenced by Pleistocene glaciations. In this study, we investigated phylogeographic patterns of a widespread mangrove species Sonneratia caseolaris and a narrowly distributed, closely related species S. lanceolata to infer their divergence histories and related it to historical geological events. We sequenced two chloroplast fragments and five nuclear genes for one population of S. lanceolata and 12 populations of S. caseolaris across the Indo-West Pacific (IWP region to evaluate genetic differentiation and divergence time among them. Phylogenetic analysis based on sequences of nuclear ribosomal internal transcribed spacer (nrITS and a nuclear gene rpl9 for all Sonneratia species indicate that S. lanceolata individuals are nested within S. caseolaris. We found strong genetic structure among geographic regions (South China Sea, the Indian Ocean and eastern Australia inhabited by S. caseolaris. We estimated that divergence between the Indo-Malesia and Australasia populations occurred 4.035 million years ago (MYA, prior to the onset of Pleistocene. BARRIERS analysis suggested that complex geographic features in the IWP region had largely shaped the phylogeographic patterns of S. caseolaris. Furthermore, haplotype analyses provided convincing evidence for secondary contact of the South China Sea (SCS and the Indian Ocean lineages at the Indo-Pacific boundary. Demographic history inference under isolation and migration (IM model detected substantial gene flow from the Sri Lanka populations to the populations in the Java Island. Moreover, multi-locus sequence analysis indicated that S. lanceolata was most closely related to the Indian Ocean populations of S. caseolaris and the divergence time between them was 2.057 MYA, coinciding with the onset of the Pleistocene

Genomic analysis for managing small and endangered populations: A case study in Tyrol Grey cattle

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Gábor eMészáros

2015-05-01

Full Text Available Analysis of genomic data is increasingly becoming part of the livestock industry. Therefore the routine collection of genomic information would be an invaluable resource for management of breeding programs in small, endangered populations. The objectives of this project were to analyse 1. linkage disequlibrium decay and the effective population size; 2. Inbreeding level and effective population size (NeROH based on runs of homozygosity (ROH; 3. Prediction of genomic breeding values (GEBV within and across breeds. In addition, the use of genomic information for breed management is discussed. The study was based on all available genotypes of Tyrol Grey AI bulls. ROHs were derived based on regions covering at least 4 Mb, 8 Mb and 16 Mb regions, with the corresponding mean inbreeding coefficients 4.0%, 2.9% and 1.6%, respectively. The NeROH was 125 (NeROH>16Mb, 186 (NeROH>8Mb and 370 (NeROH>4Mb, indicating strict avoidance of close inbreeding in the population.The genomic selection was developed for and is working well in large breeds. Contrary to the expectations, the accuracy of GEBVs with very small within breed reference populations were very high, between 0.13-0.91 and 0.12-0.63, when EBVs and dEBVs were used as pseudo-phenotypes, respectively. Subsequent analyses confirmed the high accuracies being heavily influenced by parent averages. Multi-breed and across breed reference sets gave inconsistent and lower accuracies. Genomic information may have a crucial role in management of small breeds. It allows to assess relatedness between individuals, trends in inbreeding and to take decisions accordingly. These decisions would be based on the real genome architecture, rather than conventional pedigree information, which can be missing or incomplete. We strongly suggest the routine genotyping of all individuals that belong to a small breed in order to facilitate the effective management of endangered livestock populations.

Social deprivation and population density are not associated with small area risk of amyotrophic lateral sclerosis.

Science.gov (United States)

Rooney, James P K; Tobin, Katy; Crampsie, Arlene; Vajda, Alice; Heverin, Mark; McLaughlin, Russell; Staines, Anthony; Hardiman, Orla

2015-10-01

Evidence of an association between areal ALS risk and population density has been previously reported. We aim to examine ALS spatial incidence in Ireland using small areas, to compare this analysis with our previous analysis of larger areas and to examine the associations between population density, social deprivation and ALS incidence. Residential area social deprivation has not been previously investigated as a risk factor for ALS. Using the Irish ALS register, we included all cases of ALS diagnosed in Ireland from 1995-2013. 2006 census data was used to calculate age and sex standardised expected cases per small area. Social deprivation was assessed using the pobalHP deprivation index. Bayesian smoothing was used to calculate small area relative risk for ALS, whilst cluster analysis was performed using SaTScan. The effects of population density and social deprivation were tested in two ways: (1) as covariates in the Bayesian spatial model; (2) via post-Bayesian regression. 1701 cases were included. Bayesian smoothed maps of relative risk at small area resolution matched closely to our previous analysis at a larger area resolution. Cluster analysis identified two areas of significant low risk. These areas did not correlate with population density or social deprivation indices. Two areas showing low frequency of ALS have been identified in the Republic of Ireland. These areas do not correlate with population density or residential area social deprivation, indicating that other reasons, such as genetic admixture may account for the observed findings. Copyright © 2015 Elsevier Inc. All rights reserved.

Glass Barriers : Constraints to Women's Small-Scale Cross-Border Trade in Cambodia and Lao PDR

OpenAIRE

Seror, Marlon; Record, Richard; Clarke, Julian

2017-01-01

Trade facilitation projects often assume indirect benefits for small-scale, cross-border traders. Recent studies have shown the challenges faced in Africa by this population, especially women, but it remains unknown in Cambodia and the Lao People's Democratic Republic, despite large trade facilitation investments. This paper fills this gap, thanks to an innovative mix of original qualitati...

ORDEM 3.0 and MASTER-2009 Modeled Small Debris Population Comparison

Science.gov (United States)

Krisko, P. H.; Flegel, S.

2014-01-01

The latest versions of the two premier orbital debris engineering models, NASA's ORDEM 3.0 and ESA's MASTER-2009, have been publically released. Both models have gone through significant advancements since inception, and now represent the state-of-the-art in orbital debris knowledge of their respective agencies. The purpose of these models is to provide satellite designers/operators and debris researchers with reliable estimates of the artificial debris environment in low Earth orbit (LEO) to geosynchronous orbit (GEO). The small debris environment within the size range of 1 mm to 1 cm is of particular interest to both human and robotic spacecraft programs, particularly in LEO. These objects are much more numerous than larger trackable debris and can have enough momentum to cause significant, if not catastrophic, damage to spacecraft upon impact. They are also small enough to elude routine detection by existing observation systems (radar and telescope). Without reliable detection the modeling of these populations has always coupled theoretical origins with supporting observational data in different degrees. In this paper, we present and detail the 1 mm to 1 cm orbital debris populations from both ORDEM 3.0 and MASTER-2009 in LEO. We review population categories: particle sources for MASTER-2009, particle densities for ORDEM 3.0. We describe data sources and their uses, and supporting models. Fluxes on spacecraft for chosen orbits are also presented and discussed within the context of each model.

Should I stay or should I go? Dispersal and population structure in small, isolated desert populations of West African crocodiles.

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Guillermo Velo-Antón

Full Text Available The maintenance of both spatial and genetic connectivity is paramount to the long-term persistence of small, isolated populations living in environments with extreme climates. We aim to identify the distribution of genetic diversity and assess population sub-structuring and dispersal across dwarfed desert populations of Crocodylus suchus, which occur in isolated groups, usually less than five individuals, along the mountains of Mauritania (West Africa. We used both invasive and non-invasive sampling methods and a combination of mitochondrial DNA (12 S and ND4 and microsatellite markers (32 loci and a subset of 12 loci. Our results showed high genetic differentiation and geographic structure in Mauritanian populations of C. suchus. We identified a metapopulation system acting within four river sub-basins (high gene flow and absence of genetic structure and considerable genetic differentiation between sub-basins (FST range: 0.12-0.24 with rare dispersal events. Effective population sizes tend to be low within sub-basins while genetic diversity is maintained. Our study suggests that hydrographic networks (temporal connections along seasonal rivers during rainy periods allow C. suchus to disperse and maintain metapopulation dynamics within sub-basins, which attenuate the loss of genetic diversity and the risk of extinction. We highlight the need of hydrographic conservation to protect vulnerable crocodiles isolated in small water bodies. We propose C. suchus as an umbrella species in Mauritania based on ecological affinities shared with other water-dependent species in desert environments.

Barriers, drivers and decision-making process for industrial energy efficiency: A broad study among manufacturing small and medium-sized enterprises

International Nuclear Information System (INIS)

Trianni, Andrea; Cagno, Enrico; Farné, Stefano

2016-01-01

Highlights: • Barriers and drivers vary along the decision-making process of EEM adoption. • Economic barriers, awareness and behavioural are most critical. • Beside economic drivers, major relevance of regulatory and vocational training. • Importance of stakeholders providing technical support. • Barriers and drivers are different according to several firm characteristics. - Abstract: Energy efficiency has been recognized as a primary means to increase the competitiveness of the industrial sector, and in particular for small and medium-sized enterprises (SMEs), in which energy efficiency measures (EEMs) are scarcely implemented. For this reason, future policies should carefully address such issue. Hence, it is really crucial to have a precise and punctual knowledge of the barriers to be tackled in the decision-making process of adopting an EEM and the drivers to be promoted. This study discussed the findings from a broad investigation within 222 manufacturing SMEs located in a Northern Italy region. Beside economic issues particularly affecting SMEs, awareness and behavioural issues emerge as critical, affecting the very first steps of the decision-making process, related to the punctual identification and evaluation of plausible EEMs. The support from manufacturers, technology suppliers, installers and ESCOs supporting SMEs through vocational training drivers (e.g. technical support) is really important to tackle such issues. More generally, beside financial institutions, the supply chain of technologies is recognized as particularly useful for supporting enterprises in the adoption of EEMs. Additionally, having previously conducted energy audit and implemented EEMs are critical factors able to highlight non-economic barriers and drivers. Therefore, the promotion of EEMs will necessarily imply a further effort in pointing out the so-called non-energy benefits (NEBs) from the implementation of EEMs. Finally, our study reveals that smaller and non

Barrier effects of roads on movements of small mammals

Czech Academy of Sciences Publication Activity Database

Rico, Adriana; Kindlmann, Pavel; Sedláček, František

2007-01-01

Roč. 56, č. 1 (2007), s. 1-12 ISSN 0139-7893 R&D Projects: GA ČR(CZ) GA206/04/0254; GA ČR(CZ) GD206/03/H034; GA MŠk LC06073 Keywords : Apodemus flavicollis * Clethrionomys glareolus * habitat fragmentation * linear clearings * road barriers * road crossing rates * Sorex araneus Subject RIV: EH - Ecology, Behaviour Impact factor: 0.376, year: 2007

Genetic diversity and stock identification of small abalone (Haliotis diversicolor) in Taiwan and Japan.

Science.gov (United States)

Hsu, Te-Hua; Gwo, Jin-Chywan

2017-01-01

Small abalone (Haliotis diversicolor) is a commercially valuable species for both fisheries and aquaculture. The production of annual farmed small abalone in Taiwan, once the highest in the world, has dramatically decreased in the past 15 years, and currently, the industry is close to collapse. Understanding the genetic diversity of small abalone and developing stock identification methods will be useful for genetic breeding, restoring collapsed stocks, managing stocks, and preventing illegal trade. We investigated 307 cultured and wild individuals from Taiwan, Japan, and Bali Island (Indonesia) by using the mitochondrial cytochrome c oxidase subunit I (COI) gene. Network analysis of mtDNA COI gene sequences revealed that the individuals collected from Taiwan, Japan, and Indonesia could be identified, and showed significant genetic divergence. In addition, the Indonesian population (Haliotis diversicolor squamata) was significantly different from the other populations and might need to be considered a separate species. We discovered a single nucleotide polymorphism marker in the mtDNA COI gene that can be used to distinguish the Taiwan population from the Japan population. We also developed a polymerase chain reaction-restriction fragment length polymorphism method for rapid detection. Furthermore, we could identify the cultured stocks, wild population, and hybrid stocks by using 6 microsatellites and amplified fragment length polymorphism. This study contributes useful tools for stock identification and the production of high-disease resistant small abalone strains (Japan × Taiwan or Taiwan × Japan). Efforts should be made to avoid unintentional random genetic mixing of the Taiwan population with the Japan population and subsequent breakdown of population differentiation, which impair local adaptation of the Taiwan wild population. Molecular markers revealed a split between the Taiwan and Japan populations, and the existence of a possible barrier to the free

POPULATION GENETICS OF Atta sexdens rubropilosa (HYMENOPTERA: FORMICIDAE

Directory of Open Access Journals (Sweden)

Liriana Belizário Cantagalli

2013-01-01

Full Text Available The genetic variability of Atta sexdens rubropilosa leaf-cutting ants collected from five brazilian localities was evaluated with PCR-RAPD technique. We used 15 primers producing 148 fragments of which 123 (83,11 % contained polymorphisms. The estimated Shannon index was 0.3836 ± 0.2335 showing that these ants possess high genetic diversity. The GST value was 0,2372 and PT = 0,184, indicating that the analyzed populations are moderately differentiated and 82 % of the variation obtained occur within populations. Although Mantel’s test had shown correlation between genetic distances and geographic was observed that Ivatuba and Itambé (33,8 km have the small geographical distance and the largest genetic distance. The lower genetic distance was estimated for Maringá and Ivatuba but this localities have a small geographic distance (42,3 km, indicating that there are no barriers for mating among reproducers in these populations. The high degree of polymorphism (83,11 % and the ability to cross among the populations in the studied regions indicate that this species of leaf-cutting ant is well adapted to the region; therefore, integrated control programs can be developed.

Population genetics of Atta sexdens rubropilosa (Hymenoptera: Formicidae)

International Nuclear Information System (INIS)

Belizario Cantagalli, Liriana; Aparecida Mangolin, Claudete; Colla Ruvolo Takasusuki, Maria Claudia

2013-01-01

The genetic variability of Atta sexdens rubropilosa leaf-cutting ants collected from five Brazilian localities was evaluated with PCR-RAPD technique. we used 15 primers producing 148 fragments of which 123 (83.11 %) contained polymorphisms. the estimated Shannon index was 0.3836 ± 0.2335 showing that these ants possess high genetic diversity. the G S T value was 0.2372 and Φ p t = 0.184, indicating that the analyzed populations are moderately differentiated and 82 % of the variation obtained occur within populations. although mantel's test had shown correlation between genetic distances and geographic was observed that Ivatuba and Itambe (33.8 km) have the small geographical distance and the largest genetic distance. the lower genetic distance was estimated for Maringa and Ivatuba but this localities have a small geographic distance (42.3 km), indicating that there are no barriers for mating among reproducers in these populations. the high degree of polymorphism (83.11 %) and the ability to cross among the populations in the studied regions indicate that this species of leaf-cutting ant is well adapted to the region; therefore, integrated control programs can be developed.

Nuclear reorganization barriers to electron transfer

International Nuclear Information System (INIS)

Sutin, N.; Brunschwig, B.S.; Creutz, C.; Winkler, J.R.

1988-01-01

The nuclear barrier to electron transfer arises from the need for reorganization of intramolecular and solvent internuclear distances prior to electron transfer. For reactions with relatively small driving force (''normal'' free-energy region) the nuclear factors and rates increase as intrinsic inner-shell and outer-shell barriers decrease; this is illustrated by data for transition metal complexes in their ground electronic states. By contrast, in the inverted free-energy region, rates and nuclear factors decrease with decreasing ''intrinsic'' barriers; this is illustrated by data for the decay of charge-transfer excited states. Several approaches to the evaluation of the outer-shell barrier are explored in an investigation of the distance dependence of the nuclear factor in intramolecular electron-transfer processes. 39 refs., 14 figs., 3 tabs

Challenges for providing health care in traumatized populations: barriers for PTSD treatments and the need for new developments.

Science.gov (United States)

Kazlauskas, Evaldas

2017-01-01

There is a growing recognition about the effects of traumatic experiences on mental health worldwide. With ongoing conflicts, natural disasters, interpersonal violence, and other traumatic events it is estimated that approximately 70% of the global population have been exposed to at least one lifetime traumatic experience. Research shows a substantial proportion of survivors, especially in low- and middle-income countries, would have a posttraumatic stress disorder (PTSD). During recent decades effective evidence-based treatments for PTSD have been developed. However, there are significant barriers to mental health services and trauma-informed treatments are not easily available for trauma survivors. From the perspective of social psychotraumatology several core barriers to trauma treatments were identified, including the lack of acknowledgment, and avoidance of disclosure. The need for cultural sensitivity in PTSD treatments, the potential of alternative ways of treatment delivery, and the involvement of non-professional volunteers are proposed as directions for future developments in the field.

Spatial and temporal dynamics of the genetic organization of small mammal populations

International Nuclear Information System (INIS)

Smith, M.H.; Manlove, M.N.; Joule, J.

1978-01-01

A functional population is a group of organisms and their offspring that contributes to a common gene pool within a certain area and time period. It is also the unit of evolution and should be viewed both in quantitative and qualitative terms. Selection, drift, dispersal, and mutation can alter the composition of populations. Spatial heterogeneity in allele frequencies argues for a conceptual model that has a series of relatively small populations semi-isolated from one another. Because of the relatively high levels of genetic variability characteristic of most mammalian species, significant amounts of gene flow between these spatially subdivided populations must occur when longer time periods are considered. Fluctuations in the genetic structure of populations seem to be important in altering the fitness of the individuals within the populations. The interaction of populations through gene flow is important in changing the levels of intrapopulational genetic variability. Populations can be characterized as existing on a continuum from relatively stable to unstable numbers and by other associated changes in their characteristics. Temporal changes in allele frequency occur in a variety of mammals. Conceptually, a species can be viewed as a series of dynamic populations that vary in numbers and quality in both a spatial and temporal context even over short distances and time periods. Short term changes in the quality of individuals in a population can be important in altering the short term dynamics of a population

Barriers to Technology Use in Large and Small School Districts

Science.gov (United States)

Francom, Gregory M.

2016-01-01

Barriers to effective technology integration come in several different categories, including access to technology tools and resources, technology training and support, administrative support, time to plan and prepare for technology integration, and beliefs about the importance and usefulness of technology tools and resources. This study used…

Patient-related barriers to hypertension control in a Nigerian population

Science.gov (United States)

Okwuonu, Chimezie Godswill; Ojimadu, Nnamdi Ezekiel; Okaka, Enajite Ibiene; Akemokwe, Fatai Momodu

2014-01-01

Background Hypertension control is a challenge globally. Barriers to optimal control exist at the patient, physician, and health system levels. Patient-related barriers in our environment are not clear. The aim of this study was to identify patient-related barriers to control of hypertension among adults with hypertension in a semiurban community in South-East Nigeria. Methods This was a cross-sectional descriptive study of patients with a diagnosis of hypertension and on antihypertensive medication. Results A total of 252 participants were included in the survey, and comprised 143 males (56.7%) and 109 females (43.3%). The mean age of the participants was 56.6±12.7 years, with a diagnosis of hypertension for a mean duration of 6.1±3.3 years. Among these patients, 32.9% had controlled blood pressure, while 39.3% and 27.8%, respectively, had stage 1 and stage 2 hypertension according to the Seventh Report of the Joint National Committee on Prevention, Detection and Evaluation of High Blood Pressure. Only 23.4% knew the consequences of poor blood pressure control and 64% were expecting a cure from treatment even when the cause of hypertension was not known. Furthermore, 68.7% showed low adherence to medication, the reported reasons for which included forgetfulness (61.2%), financial constraints (56.6%), high pill burden (22.5%), side effects of medication (17.3%), and low measured blood pressure (12.1%). Finally, knowledge and practice of the lifestyle modifications necessary for blood pressure control was inadequate among the participants. Conclusion Poor knowledge regarding hypertension, unrealistic expectations of treatment, poor adherence with medication, unawareness of lifestyle modification, and failure to apply these were identified as patient-related barriers to blood pressure control in this study. PMID:25061335

Population ecology of small mammals on the radioactive waste management complex, Idaho National Engineering Laboratory

International Nuclear Information System (INIS)

Groves, C.R.; Keller, B.L.

1983-01-01

Species composition, diversity, biomass, population dynamics, absolute density, and movements of small mammal populations were examined on and adjacent to a solid radioactive waste disposal area in southeastern Idaho. The 15-month live-trapping study resulted in marking 2384 individuals representing 10 species of small mammals. Three vegetation types were sampled: crested wheatgrass (Agropyron cristatum) and Russian thistle (Salsola kali) habitats on the disposal area and native sagebrush (Artemisia tridentata) habitat surrounding the disposal area. The deer mouse (Peromyscus maniculatus) was the most common rodent in both disposal area habitats as well as the adjacent sagebrush habitat; Ord's kangaroo rat (Dipodomys ordii) was also an abundant rodent in all vegetation types. The montane vole (Microtus montanus) was common only in crested wheatgrass stands on the disposal area. The annual total small mammal biomass of 346 kg for the entire disposal area represents a potentially large vector for movement of radionuclides off the disposal area. However, the number of animals known to contact waste areas and traverse at least 50 m beyond the perimeter of the SDA appears to be small (8.7%)

Global multi-decadal ocean climate and small-pelagic fish population

International Nuclear Information System (INIS)

Tourre, Yves M; Lluch-Cota, Salvador E; White, Warren B

2007-01-01

Ocean climate, environmental and biological conditions vary on several spatio-temporal scales. Besides climate change associated with anthropogenic activity, there is growing evidence of a natural global multi-decadal climate signal in the ocean-atmosphere-biosphere climate system. The spatio-temporal evolution of this signal is thus analyzed during the 20th century and compared to the variability of small-pelagic fish landings. It is argued that the low-frequency global ocean environment and plankton ecosystems must be modified such that small-pelagic populations vary accordingly. A small-pelagic global index or fishing 'regime indicator series' (RIS) (i.e. a small-pelagic abundance indicator) is used. RIS is derived from fish landings data in the four main fishing areas in the Pacific and Atlantic oceans. Global RIS changes phase (from positive to negative values) when SST multi-decadal anomalies are out-of-phase between the eastern Pacific and southern Atlantic. RIS also displays maxima during the mid-30s to early-40s and the late-70s to early-80s when the multi-decadal signal was approximately changing phases (Tourre and White 2006 Geophys. Res. Lett. 33 L06716). It is recognized that other factors may modulate fish stocks, including anthropogenic predation. Nevertheless it is proposed that variable climate and environment, and the low-frequency 'global synchrony' of small-pelagic landings (Schwartzlose et al 1999 S. Afr. J. Mar. Sci. 21 289-347), could be associated with the multi-decadal changes in global ocean climate conditions

Estimation and management of genetic diversity in small populations of plains zebra (Equus quagga) in KwaZulu-Natal, South Africa.

Science.gov (United States)

Bowland, A E.; Bishop, K S.; Taylor, P J.; Lamb, J; van der Bank, F H.; van Wyk, E; York, D

2001-06-01

Plains zebras (Equus quagga antiquorum) occur in few large, but many small, isolated populations in KwaZulu-Natal. Problems identified in small populations include reduced striping patterns on hind quarters, smaller size, elevated mortality rates and high number of still-births. Inbreeding may be implicated. Population viability analysis (PVA) was conducted with a computer model (VORTEX), and DNA and allozyme analyses were conducted to test the findings of the model. Using standard methods, DNA (PCR-RAPD) and allozyme diversity was assessed in blood samples from 72 plains zebra from four KwaZulu-Natal Nature Conservation Services (KZN-NCS) protected areas: Umfolozi Game Reserve (UGR), Albert Falls (AFNR), Vernon Crookes (VCNR) and Harold Johnson (HJNR) Nature Reserves. Populations of the latter three, small-sized (9-110 individuals) populations were seeded from the same source population (UGR: current population of 2000) during the past 25 years. Information from PCR-RAPD and allozyme analyses were compared with each other as well as to that predicted by population genetic modelling (using VORTEX). Allozyme heterozygosities were consistently high in all populations (12.1-12.9%), with no observable losses associated with reduced population size. On the other hand, percentage loss of polymorphism (20-39%) calculated from the PCR-RAPD study appeared to be positively correlated with the loss of heterozygosity predicted by population viability analysis (PVA), and negatively correlated with population size. On the basis of the above results, a policy of translocation was advocated for small, intensely managed populations of zebras, whereby a harem should be translocated every five years for a population size of nine (HJNR), while for a population size of 110 (VCNR) translocations should take place every 15 years if heterozygosity is to be maintained at more than 90% within each population over 100 years.

BARRIERS TO PHYSICAL ACTIVITY IN THE ELDERLY

Directory of Open Access Journals (Sweden)

Paulo Matias

2015-04-01

Full Text Available The population awareness of the physical exercise’s benefits is widely diffused. These benefits are particularly important in the elderly because, with increasing age, there is a decline of the musculoskeletal system and the maximum oxygen consumption which reduces the functional fitness of the elderly and can often lead to a significant decline in the quality of life. Despite this awareness, a large part of the population remains sedentary. It is important to know what the barriers are, so they can be circumvented in order to increase the engagement of the elderly population in existing physical activity programs.Objectives: This study aims to identify some of the personal, behavioral and environmental barriers that prevent older adults to be physically active.

Environmental influences on small eating behavior change to promote weight loss among Black and Hispanic populations.

Science.gov (United States)

Eldridge, Johanna D; Devine, Carol M; Wethington, Elaine; Aceves, Luz; Phillips-Caesar, Erica; Wansink, Brian; Charlson, Mary E

2016-01-01

Small eating behavior changes are proposed as more feasible to achieve and maintain than larger changes used in traditional behavioral weight loss studies. However, it is unclear whether overweight Black and Hispanic adults in a low-income urban setting experience small changes as feasible and what might influence feasibility. Participants' experiences in a 12-week pilot weight loss intervention were explored qualitatively to determine the feasibility of making small eating behavior changes in this population. After the intervention (69% retention), semi-structured interviews with 46 men and women (mean age 51, 50% Non-Hispanic Black, 43% Hispanic) revealed that making small eating changes was a process shaped by participants' intrapersonal and interpersonal eating environments. Participants responded to intrapersonal and interpersonal eating environmental challenges by adapting small change strategies, navigating eating environments, and negotiating household eating practices. Findings highlight how even small eating behavior changes called for adaptation, navigation, and negotiation of complex eating environments in daily life. These findings were used to improve the trial that followed and underline the importance of feasibility studies to inform community trials. Findings also add to understanding of contextual challenges and the skills needed to implement small changes in a low income, ethnic minority population. Copyright © 2015. Published by Elsevier Ltd.

Socio-demographic and behavioral variation in barriers to leisure-time physical activity.

Science.gov (United States)

Borodulin, Katja; Sipilä, Noora; Rahkonen, Ossi; Leino-Arjas, Päivi; Kestilä, Laura; Jousilahti, Pekka; Prättälä, Ritva

2016-02-01

We examined the socio-demographic and behavioral determinants of perceived barriers to leisure-time physical activity (LTPA) in a population-based sample of working-aged adults. Data comprised the National FINRISK 2002 Study, a population-based health examination study. Analyses were restricted to those aged 25-64 years and who perceived that their amount of LTPA did not reach sufficient levels. They reported barriers to LTPA, defined as a lack of time, motivation and lack of companionship to be active with, as well as high expenses. Age, education, household income, employment status, family type, physical activity, smoking and body mass index (BMI) were included as explanatory variables. Lack of time was the most frequent barrier. Each barrier was explained by a different set of factors that also varied between genders. The strongest and most systematic associations with the barriers were found for age, employment status and family type. Lack of time was less often reported as a barrier among the unemployed, singles without children and older people. Lacking motivation as a barrier was most common among singles without children. High expenses as a barrier was more often reported by the unemployed, and less often reported in the highest income group. When considering actions to promote LTPA, there is not one single solution, because the perceived barriers vary by population subgroups. © 2015 the Nordic Societies of Public Health.

Origin of Small Barriers in Jahn–Teller Systems

DEFF Research Database (Denmark)

Barriuso, M. T.; Ortiz-Sevilla, B.; Aramburu, J. A.

2013-01-01

. It is quantitatively proven that the elongated geometry observed for NaCl:Ni+ is due to the 3d–4s vibronic admixture, which is slightly larger than the anharmonicity in the eg JT mode that favors a compressed geometry. The existence of these two competing mechanisms explains the low value of B for the model system......Despite its relevance, the microscopic origin of the energy barrier, B, between the compressed and elongated geometries of Jahn–Teller (JT) systems is not well understood yet because of a lack of quantitative data about its various contributions. Seeking to clear up this matter, we have carried out...

Long term performance of the Waterloo denitrification barrier

International Nuclear Information System (INIS)

Robertson, W.D.; Cherry, J.A.

1997-01-01

Beginning in 1991 a series of laboratory tests and small scale field trials were initiated to test the performance of an innovative permeable reactive barrier for treatment of nitrate from septic systems. The barrier promotes denitrification by providing an energy source in the form of solid organic carbon mixed into the porous media material. Advantages of the system for nitrate treatment are that the reaction is passive and in situ and it is possible to incorporate sufficient carbon mass in conveniently sized barriers to potentially provide treatment for long periods (decades) without the necessity for maintenance. However, longevity can only be demonstrated by careful long term monitoring of field installations. This paper documents four years of operating history at three small scale field trials; two where the denitrification barrier is installed as a horizontal layer positioned in the unsaturated zone below conventional septic system infiltration beds and one where the barrier is installed as a vertical wall intercepting a septic system plume at a downgradient location. The barriers have successfully attenuated 50-100% of NO - 3 -N levels of up to 170 mg/L and treatment has remained consistent over the four year period in each case, thus considerable longevity is indicated. Other field trials have demonstrated this technology to be equally effective in treating nitrogen contamination from other sources such as landfill leachate and farm field runoff

Small population size of Pribilof Rock Sandpipers confirmed through distance-sampling surveys in Alaska

Science.gov (United States)

Ruthrauff, Daniel R.; Tibbitts, T. Lee; Gill, Robert E.; Dementyev, Maksim N.; Handel, Colleen M.

2012-01-01

The Rock Sandpiper (Calidris ptilocnemis) is endemic to the Bering Sea region and unique among shorebirds in the North Pacific for wintering at high latitudes. The nominate subspecies, the Pribilof Rock Sandpiper (C. p. ptilocnemis), breeds on four isolated islands in the Bering Sea and appears to spend the winter primarily in Cook Inlet, Alaska. We used a stratified systematic sampling design and line-transect method to survey the entire breeding range of this population during springs 2001-2003. Densities were up to four times higher on the uninhabited and more northerly St. Matthew and Hall islands than on St. Paul and St. George islands, which both have small human settlements and introduced reindeer herds. Differences in density, however, appeared to be more related to differences in vegetation than to anthropogenic factors, raising some concern for prospective effects of climate change. We estimated the total population at 19 832 birds (95% CI 17 853–21 930), ranking it among the smallest of North American shorebird populations. To determine the vulnerability of C. p. ptilocnemis to anthropogenic and stochastic environmental threats, future studies should focus on determining the amount of gene flow among island subpopulations, the full extent of the subspecies' winter range, and the current trajectory of this small population.

Cumulative Effects of Barriers on the Movements of Forest Birds

Directory of Open Access Journals (Sweden)

Marc Bélisle

2002-01-01

Full Text Available Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration from habitat loss (composition, and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species of forest birds in the Bow Valley of Banff National Park, Canada. Birds were translocated (1.2-3.5  km either parallel or perpendicular to four/five parallel barriers that are assumed to impede the cross-valley travel of forest-dependent animals. Taken together, individuals exhibited longer return times when they were translocated across these barriers, but differences among species suggest a more complex interpretation. A long-distance migrant (Yellow-rumped Warbler, Dendroica coronata behaved as predicted, but a short-distance migrant (Golden-crowned Kinglet, Regulus satrapa was indifferent to barrier configuration. A resident (Red-breasted Nuthatch, Sitta canadensis exhibited longer return times when it was translocated parallel to the barriers. Our results suggest that an anisotropic arrangement of small, open areas in fragmented landscapes can have a cumulative barrier effect on the movement of forest animals, but that both modelers and managers will have to acknowledge potentially counterintuitive differences among species to predict the effect that these may have on individual movement and, ultimately, dispersal.

Influence of small hydropower plants on brown trout (Salmo trutta L. population in Mislinja River

Directory of Open Access Journals (Sweden)

Blaž Cokan

2013-12-01

Full Text Available The brown trout (Salmo trutta L. in the Mislinja River has been endangered for years because of small hydroelectric power plants. To find out how they are affecting the population of the brown trout in the Mislinja River, we conducted a sampling of the brown trout, using a generating set. We measured the length and weight of all caught specimens and analysed the obtained data. The results are presented in this paper, e.g., biomass, estimations of abundance, average weight, average length and number of captured brown trout. We discovered that the population of the brown trout has decreased in all the sections where water has been taken away for small hydroelectric power plants.

Vertical barriers with increased sorption capacities

International Nuclear Information System (INIS)

Bradl, H.B.

1997-01-01

Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed 'tailor-made' depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents

Barriers to treatment for older adults seeking psychological therapy.

Science.gov (United States)

Wuthrich, Viviana M; Frei, Jacqueline

2015-07-01

Older adults with mental health disorders underutilize mental health services more than other adults. While there are well known general barriers to help seeking across the population, specific barriers for older adults include difficulties with transportation, beliefs that it is normal to be anxious and depressed in old age, and beliefs by referrers that psychological therapy is less likely to be effective. This study examined barriers related to identifying the need for help, seeking help and participating in therapy in a clinical population of older adults. Sixty older adults (aged 60-79 years) with comorbid anxiety and unipolar mood disorders completed barriers to treatment questionnaires before and after psychological group treatment, as well as measures of cognitive ability, anxiety, depression, and quality of life at baseline. The greatest barriers to help seeking related to difficulties identifying the need for help, with 50% of the sample reporting their belief that their symptoms were normal as a major barrier. Other major barriers identified were related to: self-reliance, cost of treatment, and fear of medication replicating previous findings. The main barriers reported for difficulties in continuing therapy included not finding therapy helpful, cost of treatment, and thinking that the therapist did not understand their issues. The main barriers identified related to issues with identifying the need to seek help. More attention is needed to educate older adults and professionals about the need for, and effectiveness of, psychological therapies for older adults with anxiety and depression to reduce this barrier to help seeking.

An Analysis of Language as a Barrier to Receiving Influenza Vaccinations among an Elderly Hispanic Population in the United States

OpenAIRE

Pearson, William S.; Zhao, Guixiang; Ford, Earl S.

2010-01-01

Background. The Hispanic population in the United States is growing, and disparities in the receipt of healthcare services as a result of limited English proficiency have been demonstrated. We set out to determine if Spanish language preference was a barrier to receiving influenza vaccinations among Hispanic persons 65 years and older in the USA. Methods. Differences in the receipt of vaccinations by language preference were tested with both Chi-square analyses and adjusted logistic regressio...

The control of an invasive bivalve, Corbicula fluminea, using gas impermeable benthic barriers in a large natural lake.

Science.gov (United States)

Wittmann, Marion E; Chandra, Sudeep; Reuter, John E; Schladow, S Geoffrey; Allen, Brant C; Webb, Katie J

2012-06-01

Anoxia can restrict species establishment in aquatic systems and the artificial promotion of these conditions can provide an effective control strategy for invasive molluscs. Low abundances (2-20 m(-2)) of the nonnative bivalve, Asian clam (Corbicula fluminea), were first recorded in Lake Tahoe, CA-NV in 2002 and by 2010 nuisance-level population densities (>10,000 m(-2)) were observed. A non-chemical control method using gas impermeable benthic barriers to reduce dissolved oxygen (DO) concentrations available to C. fluminea was tested in this ultra-oligotrophic natural lake. In 2009, the impact of ethylene propylene diene monomer (EPDM) sheets (9 m(2), n = 6) on C. fluminea beds was tested on 1-7 day intervals over a 56 day period (August-September). At an average water temperature of 18 °C, DO concentrations under these small barriers were reduced to zero after 72 h resulting in 100 % C. fluminea mortality after 28 days. In 2010, a large EPDM barrier (1,950 m(2)) was applied to C. fluminea populations for 120 days (July-November). C. fluminea abundances were reduced over 98 % after barrier removal, and remained significantly reduced (>90 %) 1 year later. Non-target benthic macroinvertebrate abundances were also reduced, with variable taxon-specific recolonization rates. High C. fluminea abundance under anoxic conditions increased the release of ammonium and soluble reactive phosphorus from the sediment substrate; but levels of unionized ammonia were low at 0.004-0.005 mg L(-1). Prolonged exposure to anoxia using benthic barriers can provide an effective short term control strategy for C. fluminea.

Slowly switching between environments facilitates reverse evolution in small populations

Science.gov (United States)

Tan, Longzhi; Gore, Jeff

2011-03-01

The rate at which a physical process occurs usually changes the behavior of a system. In thermodynamics, the reversibility of a process generally increases when it occurs at an infinitely slow rate. In biological evolution, adaptations to a new environment may be reversed by evolution in the ancestral environment. Such fluctuating environments are ubiquitous in nature, although how the rate of switching affects reverse evolution is unknown. Here we use a computational approach to quantify evolutionary reversibility as a function of the rate of switching between two environments. For small population sizes, which travel on landscapes as random walkers, we find that both genotypic and phenotypic reverse evolution increase at slow switching rates. However, slow switching of environments decreases evolutionary reversibility for a greedy walker, corresponding to large populations (extensive clonal interference). We conclude that the impact of the switching rate for biological evolution is more complicated than other common physical processes, and that a quantitative approach may yield significant insight into reverse evolution.

Understanding barriers to the introduction of precision medicines in non-small cell lung cancer: A qualitative interview protocol [version 1; referees: 2 approved

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Stuart Wright

2018-03-01

Full Text Available Background: While precision medicines targeting genetic mutations and alterations in non-small cell lung cancer (NSCLC have been available since 2010, their adoption into clinical practice has been slow. Evidence suggests that a number of barriers, such as insufficient clinician knowledge, a need for training of test providers, or a lack of specific clinical guidelines, may slow the implementation of precision in general. However, little attention has been given to the barriers to providing precision medicines in NSCLC. The purpose of this protocol is to outline the design for a qualitative interview study to identify the barriers and facilitators to the provision of precision medicines for NSCLC.   Methods: This study will use semi-structured interviews with clinicians (n=10, test providers (n=10, and service commissioners (n=10 to identify the perceived barriers and facilitators to providing historical, current, and future precision medicines in NSCLC. Participants will be identified through mailing list advertisements and snowball sampling. Recruitment will continue until data saturation, indicated by no new themes arising from the data. Interviews will be conducted by telephone to facilitate geographical diversity. The qualitative data will be analysed using a framework analysis with themes anticipated to relate to; relevant barriers to providing precision medicines, the impact of different barriers on medicine provision, changes in the ability to provide precision medicines over time, and strategies to facilitate the provision of precision medicines.   Ethics: This study has been approved by the University of Manchester Proportionate Review Research Ethics Committee (Reference number: 2017-1885-3619. Written consent will be obtained from all participants.   Conclusion: This study is the first to explore the barriers and facilitators to providing precision medicines for NSCLC in the English NHS. The findings will inform strategies to

Barriers to Distance Education in Rural Schools

Science.gov (United States)

Irvin, Matthew J.; Hannum, Wallace H.; Varre, Claire de la; Farmer, Thomas W.

2010-01-01

The primary purpose of the current study was to examine barriers to the use of distance education and explore related factors in small and low-income rural schools. Data were collected via a telephone survey with administrators or other qualified personnel. The sample involved 417 randomly selected small and low-income rural school districts…

Barriers to e-marketing adoption among small and medium enterprises (SMEs in the Vaal Triangle

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N. Dlodlo

2010-12-01

Full Text Available Purpose: The purpose of the study is to complement existing literature by examining the relevant barriers contributing to the non-adoption of electronic marketing practices by SMEs in the Vaal Triangle. Methodology: Primary data was collected using a quantitative research technique with the use of a structured questionnaire as the survey instrument. A total of 168 businesses were selected randomly and visited within the various municipal areas in the Vaal Triangle. These businesses were visited between August and November 2008. Thirty-two small, medium and medium enterprises SMEs refused to participate resulting in 123 usable questionnaires for the purposes of the analysis. Factor analysis was used to examine the robustness of the factor structure using principal component analysis. Findings: A five-dimensional structure was established comprising a 16 item-scale. The major impediments towards the non-adoption of e-marketing include technology incompatibility with target markets, lack of knowledge, stakeholder unreadiness, technology disorientation and technology perception. The reliability analysis, reflected coefficient values ranging from 0.70 to 0.88 indicating satisfactory internal consistency amongst variables within each dimension. Implications: By analysing the barriers that inhibit the adoption of e-marketing strategies among SMEs, marketers are presented with recommended strategies and implications on how to approach the challenges presented by Internet technological advancements. Internet capacities of SMEs may be strengthened through nurturing e-marketing awareness and providing adequate information tools through diverse Internet Marketing training programmes. Originality/Value: SMEs can prove to be a major source of economic growth for many African countries if sufficient guidance and support on how best to overcome the challenges of adopting advanced marketing practices is available.

Distinguishing pathological from constitutional small for gestational age births in population-based studies.

Science.gov (United States)

Ananth, Cande V; Vintzileos, Anthony M

2009-10-01

Small for gestational age (SGA) can occur following a pathological process or may represent constitutionally small fetuses. However, distinguishing these processes is often difficult, especially in large studies, where the term SGA is often used as a proxy for restricted fetal growth. Since biologic variation in fetal size is largely a third trimester phenomenon, we hypothesized that the definition of SGA at term may include a sizeable proportion of constitutionally small fetuses. In contrast, since biologic variation in fetal size is not fully expressed in (early) preterm gestations, it is plausible that SGA in early preterm gestations would comprise a large proportion of growth restricted fetuses. We compared mortality and morbidity rates between SGA and appropriate for gestational age (AGA) babies. A population-based study of over 19million non-malformed, singleton births (1995-04) in the United States was performed. Gestational age (24-44weeks) was based on a clinical estimate. SGA and AGA were defined as sex-specific birthweight constitutionally small.

Social Barriers to Effective Communication in Old Age

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Anna Sanecka

2014-12-01

Full Text Available Some communication barriers apply particularly to elderly people. The social barriers to effective communication in old age are the barriers caused by stereotypes of old age/elderly people and the barriers arising from limitations in using mass communication by seniors. Stereotypes of old age/elderly people embrace views regarding old people’s communication skills and the ideas about the correct way of communication with them. Therefore the communication problems of old people are correlated with the little and poor communication processes they are participating in. This seems to be a result of impetuses of poor quality sent to seniors by their communication partners. Not only face to face communication but also mass communication is very important for the elderly population. Therefore limitations in using new technologies and new communication channels as well as a limited presence in the mass media of content created by seniors and for seniors have an impact on their life, their well-being, and their interpersonal relationships. These problems are especially important when we faced with the ever growing population of elderly people.

A population genetic assessment of coral recovery on highly disturbed reefs of the Keppel Island archipelago in the southern Great Barrier Reef

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Madeleine J.H. van Oppen

2015-07-01

Full Text Available Coral reefs surrounding the islands lying close to the coast are unique to the Great Barrier Reef (GBR in that they are frequently exposed to disturbance events including floods caused by cyclonic rainfall, strong winds and occasional periods of prolonged above-average temperatures during summer. In one such group of islands in the southern GBR, the Keppel Island archipelago, climate-driven disturbances frequently result in major coral mortality. Whilst these island reefs have clearly survived such dramatic disturbances in the past, the consequences of extreme mortality events may include the loss of genetic diversity, and hence adaptive potential, and a reduction in fitness due to inbreeding, especially if new recruitment from external sources is limited. Here we examined the level of isolation of the Keppel Island group as well as patterns of gene flow within the Keppel Islands using 10 microsatellite markers in nine populations of the coral, Acropora millepora. Bayesian cluster analysis and assignment tests indicated gene flow is restricted, but not absent, between the outer and inner Keppel Island groups, and that extensive gene flow exists within each of these island groups. Comparison of the Keppel Island data with results from a previous GBR-wide study that included a single Keppel Island population, confirmed that A. millepora in the Keppel Islands is genetically distinct from populations elsewhere on the GBR, with exception of the nearby inshore High Peak Reef just north of the Keppel Islands. We compared patterns of genetic diversity in the Keppel Island populations with those from other GBR populations and found them to be slightly, but significantly lower, consistent with the archipelago being geographically isolated, but there was no evidence for recent bottlenecks or deviation from mutation-drift equilibrium. A high incidence of private alleles in the Keppel Islands, particularly in the outer islands, supports their relative

Subsurface barrier verification technologies, informal report

International Nuclear Information System (INIS)

Heiser, J.H.

1994-06-01

One of the more promising remediation options available to the DOE waste management community is subsurface barriers. Some of the uses of subsurface barriers include surrounding and/or containing buried waste, as secondary confinement of underground storage tanks, to direct or contain subsurface contaminant plumes and to restrict remediation methods, such as vacuum extraction, to a limited area. To be most effective the barriers should be continuous and depending on use, have few or no breaches. A breach may be formed through numerous pathways including: discontinuous grout application, from joints between panels and from cracking due to grout curing or wet-dry cycling. The ability to verify barrier integrity is valuable to the DOE, EPA, and commercial sector and will be required to gain full public acceptance of subsurface barriers as either primary or secondary confinement at waste sites. It is recognized that no suitable method exists for the verification of an emplaced barrier's integrity. The large size and deep placement of subsurface barriers makes detection of leaks challenging. This becomes magnified if the permissible leakage from the site is low. Detection of small cracks (fractions of an inch) at depths of 100 feet or more has not been possible using existing surface geophysical techniques. Compounding the problem of locating flaws in a barrier is the fact that no placement technology can guarantee the completeness or integrity of the emplaced barrier. This report summarizes several commonly used or promising technologies that have been or may be applied to in-situ barrier continuity verification

Testing the effect of the Himalayan mountains as a physical barrier to gene flow in Hippophae tibetana Schlect. (Elaeagnaceae.

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La Qiong

Full Text Available Hippophae tibetana is a small, dioecious wind-pollinated shrub endemic to the Tibetan-Qinghai Plateau. It is one of the shrubs that occur at very high elevations (5250 m a.s.l.. The Himalayan mountains provides a significant geographical barrier to the Qinghai-Tibetan Plateau, dividing the Himalayan area into two regions with Nepal to the south and Tibet to the north. There is no information on how the Himalayan mountains influence gene flow and population differentiation of alpine plants. In this study, we analyzed eight nuclear microsatellite markers and cpDNA trnT-trnF regions to test the role of the Himalayan mountains as a barrier to gene flow between populations of H. tibetana. We also examined the fine-scale genetic structure within a population of H. tibetana on the north slope of Mount (Mt. Everest. For microsatellite analyses, a total of 241 individuals were sampled from seven populations in our study area (4 from Nepal, 3 from Tibet, including 121 individuals that were spatially mapped within a 100 m × 100 m plot. To test for seed flow, the cpDNA trnT-trnF regions of 100 individuals from 6 populations (4 from Nepal, 2 from Tibet were also sequenced. Significant genetic differentiation was detected between the two regions by both microsatellite and cpDNA data analyses. These two datasets agree about southern and northern population differentiation, indicating that the Himalayan mountains represent a barrier to H. tibetana limiting gene flow between these two areas. At a fine scale, spatial autocorrelation analysis suggests significant genetic structure within a distance of less than 45 m, which may be attributed mainly to vegetative reproduction and habitat fragmentation, as well as limited gene flow.

Patient-related barriers to hypertension control in a Nigerian population

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Okwuonu CG

2014-07-01

Full Text Available Chimezie Godswill Okwuonu,1 Nnamdi Ezekiel Ojimadu,2 Enajite Ibiene Okaka,3 Fatai Momodu Akemokwe41Nephrology Unit, Department of Internal Medicine, 2Department of Family Medicine, Federal Medical Center Umuahia, Abia State, 3Renal Unit, 4Neurology Unit, Department of Internal Medicine University of Benin Teaching Hospital, Benin City, NigeriaBackground: Hypertension control is a challenge globally. Barriers to optimal control exist at the patient, physician, and health system levels. Patient-related barriers in our environment are not clear. The aim of this study was to identify patient-related barriers to control of hypertension among adults with hypertension in a semiurban community in South-East Nigeria.Methods: This was a cross-sectional descriptive study of patients with a diagnosis of hypertension and on antihypertensive medication.Results: A total of 252 participants were included in the survey, and comprised 143 males (56.7% and 109 females (43.3%. The mean age of the participants was 56.6±12.7 years, with a diagnosis of hypertension for a mean duration of 6.1±3.3 years. Among these patients, 32.9% had controlled blood pressure, while 39.3% and 27.8%, respectively, had stage 1 and stage 2 hypertension according to the Seventh Report of the Joint National Committee on Prevention, Detection and Evaluation of High Blood Pressure. Only 23.4% knew the consequences of poor blood pressure control and 64% were expecting a cure from treatment even when the cause of hypertension was not known. Furthermore, 68.7% showed low adherence to medication, the reported reasons for which included forgetfulness (61.2%, financial constraints (56.6%, high pill burden (22.5%, side effects of medication (17.3%, and low measured blood pressure (12.1%. Finally, knowledge and practice of the lifestyle modifications necessary for blood pressure control was inadequate among the participants.Conclusion: Poor knowledge regarding hypertension, unrealistic

Life expectancy estimation in small administrative areas with non-uniform population sizes: application to Australian New South Wales local government areas.

Science.gov (United States)

Stephens, Alexandre S; Purdie, Stuart; Yang, Baohui; Moore, Helen

2013-12-02

To determine a practical approach for deriving life expectancy estimates in Australian New South Wales local government areas which display a large diversity in population sizes. Population-based study utilising mortality and estimated residential population data. 153 local government areas in New South Wales, Australia. Key performance measures of Chiang II, Silcocks, adjusted Chiang II and Bayesian random effects model methodologies of life expectancy estimation including agreement analysis of life expectancy estimates and comparison of estimate SEs. Chiang II and Silcocks methods produced almost identical life expectancy estimates across a large range of population sizes but calculation failures and excessively large SEs limited their use in small populations. A population of 25 000 or greater was required to estimate life expectancy with SE of 1 year or less using adjusted Chiang II (a composite of Chiang II and Silcocks methods). Data aggregation offered some remedy for extending the use of adjusted Chiang II in small populations but reduced estimate currency. A recently developed Bayesian random effects model utilising the correlation in mortality rates between genders, age groups and geographical areas markedly improved the precision of life expectancy estimates in small populations. We propose a hybrid approach for the calculation of life expectancy using the Bayesian random effects model in populations of 25 000 or lower permitting the precise derivation of life expectancy in small populations. In populations above 25 000, we propose the use of adjusted Chiang II to guard against violations of spatial correlation, to benefit from a widely accepted method that is simpler to communicate to local health authorities and where its slight inferior performance compared with the Bayesian approach is of minor practical significance.

Comparison of small-area deprivation measures as predictors of chronic disease burden in a low-income population.

Science.gov (United States)

Lòpez-De Fede, Ana; Stewart, John E; Hardin, James W; Mayfield-Smith, Kathy

2016-06-10

Measures of small-area deprivation may be valuable in geographically targeting limited resources to prevent, diagnose, and effectively manage chronic conditions in vulnerable populations. We developed a census-based small-area socioeconomic deprivation index specifically to predict chronic disease burden among publically insured Medicaid recipients in South Carolina, a relatively poor state in the southern United States. We compared the predictive ability of the new index with that of four other small-area deprivation indicators. To derive the ZIP Code Tabulation Area-Level Palmetto Small-Area Deprivation Index (Palmetto SADI), we evaluated ten census variables across five socioeconomic deprivation domains, identifying the combination of census indicators most highly correlated with a set of five chronic disease conditions among South Carolina Medicaid enrollees. In separate validation studies, we used both logistic and spatial regression methods to assess the ability of Palmetto SADI to predict chronic disease burden among state Medicaid recipients relative to four alternative small-area socioeconomic deprivation measures: the Townsend index of material deprivation; a single-variable poverty indicator; and two small-area designations of health care resource deprivation, Primary Care Health Professional Shortage Area and Medically Underserved Area/Medically Underserved Population. Palmetto SADI was the best predictor of chronic disease burden (presence of at least one condition and presence of two or more conditions) among state Medicaid recipients compared to all alternative deprivation measures tested. A low-cost, regionally optimized socioeconomic deprivation index, Palmetto SADI can be used to identify areas in South Carolina at high risk for chronic disease burden among Medicaid recipients and other low-income Medicaid-eligible populations for targeted prevention, screening, diagnosis, disease self-management, and care coordination activities.

Allosteric small-molecule kinase inhibitors

DEFF Research Database (Denmark)

Wu, Peng; Clausen, Mads Hartvig; Nielsen, Thomas E.

2015-01-01

current barriers of kinase inhibitors, including poor selectivity and emergence of drug resistance. In spite of the small number of identified allosteric inhibitors in comparison with that of inhibitors targeting the ATP pocket, encouraging results, such as the FDA-approval of the first small...

Change in genetic size of small-closed populations: lessons from a domestic mammal population

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Farhad Ghafouri-Kesbi

2010-01-01

Full Text Available The aim of this study was to monitor changes in genetic size of a small-closed population of Iranian Zandi sheep, by using pedigree information from animals born between 1991 and 2005. The genetic size was assessed by using measures based on the probability of identity-by-descend of genes (coancestry, f, and effective population size, Ne, as well as measures based on probability of gene origin (effective number of founders, f e, effective number of founder genomes, f g, and effective number of non-founder genomes, f ne. Average coancestry, or the degree of genetic similarity of individuals, increased from 0.81% to 1.44% during the period 1993 to 2005, at the same time that Ne decreased from 263 to 93. The observed trend for f e was irregular throughout the experiment in a way that f e was 68, 87, 77, 92, and 80 in 1993, 1996, 1999, 2002, and 2005, respectively. Simultaneously, f g, the most informative effective number, decreased from 61 to 35. The index of genetic diversity (GD which was obtained from estimates of f g,decreased about 2% throughout the period studied. In addition, a noticeable reduction was observed in the estimates of f ne from 595 in 1993 to 61 in 2005. The higher than 1 ratio of f e to f g indicated the presence of bottlenecks and genetic drift in the development of this population of Zandi sheep. From 1993 to 1999, f ne was much higher than f e, thereby indicating that with respect to loss of genetic diversity, the unequal contribution of founders was more important than the random genetic drift in non-founder generations. Subsequently, random genetic drift in non-founder generations was the major reason for f e> f ne. The minimization of average coancestry in new reproductive individuals was recommended as a means of preserving the population against a further loss in genetic diversity.

Change in genetic size of small-closed populations: Lessons from a domestic mammal population.

Science.gov (United States)

Ghafouri-Kesbi, Farhad

2010-10-01

The aim of this study was to monitor changes in genetic size of a small-closed population of Iranian Zandi sheep, by using pedigree information from animals born between 1991 and 2005. The genetic size was assessed by using measures based on the probability of identity-by-descend of genes (coancestry, f, and effective population size, N(e) ), as well as measures based on probability of gene origin (effective number of founders, f(e) , effective number of founder genomes, f(g) , and effective number of non-founder genomes, f(ne) ). Average coancestry, or the degree of genetic similarity of individuals, increased from 0.81% to 1.44% during the period 1993 to 2005, at the same time that N(e) decreased from 263 to 93. The observed trend for f(e) was irregular throughout the experiment in a way that f(e) was 68, 87, 77, 92, and 80 in 1993, 1996, 1999, 2002, and 2005, respectively. Simultaneously, f(g) , the most informative effective number, decreased from 61 to 35. The index of genetic diversity (GD) which was obtained from estimates of f(g) , decreased about 2% throughout the period studied. In addition, a noticeable reduction was observed in the estimates of f(ne) from 595 in 1993 to 61 in 2005. The higher than 1 ratio of f(e) to f(g) indicated the presence of bottlenecks and genetic drift in the development of this population of Zandi sheep. From 1993 to 1999, f(ne) was much higher than f(e) , thereby indicating that with respect to loss of genetic diversity, the unequal contribution of founders was more important than the random genetic drift in non-founder generations. Subsequently, random genetic drift in non-founder generations was the major reason for f(e) > f(ne) . The minimization of average coancestry in new reproductive individuals was recommended as a means of preserving the population against a further loss in genetic diversity.

Barriers to mental health treatment for military wives.

Science.gov (United States)

Lewy, Colleen S; Oliver, Celina M; McFarland, Bentson H

2014-09-01

An Internet-based survey sought information about barriers to mental health services for military wives. On the basis of qualitative work, an Internet-based program was created to identify military wives who may have major depressive disorder. Women (N=569, ages 18 to 56) were recruited from 45 states and eight foreign countries. Most participants (78%) reported mild to severe depression. Many (44%) reported unaddressed mental health needs. Barriers included inability to attend daytime appointments (38%), inability to find a counselor who understands the needs of military spouses (35%), inability to find a counselor the participant could trust (29%), concerns about confidentiality (26%), and lack of knowledge about where to get services (25%). The barriers reported differed markedly from those described by distressed women in the general population. Military wives are an underserved population. Knowledge of military culture is essential for civilian mental health providers working with military wives.

Hybridization between two cryptic filamentous brown seaweeds along the shore: analysing pre- and postzygotic barriers in populations of individuals with varying ploidy levels.

Science.gov (United States)

Montecinos, Alejandro E; Guillemin, Marie-Laure; Couceiro, Lucia; Peters, Akira F; Stoeckel, Solenn; Valero, Myriam

2017-07-01

We aimed to study the importance of hybridization between two cryptic species of the genus Ectocarpus, a group of filamentous algae with haploid-diploid life cycles that include the principal genetic model organism for the brown algae. In haploid-diploid species, the genetic structure of the two phases of the life cycle can be analysed separately in natural populations. Such life cycles provide a unique opportunity to estimate the frequency of hybrid genotypes in diploid sporophytes and meiotic recombinant genotypes in haploid gametophytes allowing the effects of reproductive barriers preventing fertilization or preventing meiosis to be untangle. The level of hybridization between E. siliculosus and E. crouaniorum was quantified along the European coast. Clonal cultures (568 diploid, 336 haploid) isolated from field samples were genotyped using cytoplasmic and nuclear markers to estimate the frequency of hybrid genotypes in diploids and recombinant haploids. We identified admixed individuals using microsatellite loci, classical assignment methods and a newly developed Bayesian method (XPloidAssignment), which allows the analysis of populations that exhibit variations in ploidy level. Over all populations, the level of hybridization was estimated at 8.7%. Hybrids were exclusively observed in sympatric populations. More than 98% of hybrids were diploids (40% of which showed signs of aneuploidy) with a high frequency of rare alleles. The near absence of haploid recombinant hybrids demonstrates that the reproductive barriers are mostly postzygotic and suggests that abnormal chromosome segregation during meiosis following hybridization of species with different genome sizes could be a major cause of interspecific incompatibility in this system. © 2017 John Wiley & Sons Ltd.

Predictors and Barriers to Hepatitis B Screening in a Midwest Suburban Asian Population.

Science.gov (United States)

Cheng, Shanna; Li, Elton; Lok, Anna S

2017-06-01

Despite guidelines recommending hepatitis B virus (HBV) screening among the Asian population, not all Asians are screened. We assessed barriers to and factors predicting HBV screening in Michigan. Adults residing in Southeast Michigan self-identifying as Asian were surveyed at Asian grocery stores, restaurants, churches, and community events. 404 persons participated in the survey, 54 % were women, median age was 51 years, 63 % were Chinese, and 93.8 % were born outside the U.S. 181 (44.8 %) had not or could not recall having been screened for HBV. Of these, 89 % said their primary care physicians (PCP) had never brought up screening. Unscreened participants were more likely to think HBV is genetically inherited and cannot be treated than those who had been screened. They were also more likely to think they should avoid close contact with others, would bring shame to their families, and lose their job, if found to be infected with HBV. Among 223 (55.2 %) who had been screened, 48 % said their PCP had the greatest influence in their decision to be screened and 70.9 % said they were screened at a doctor's visit. Screened participants were more likely to know someone with HBV, have a PCP, and have health insurance. Logistic regression analysis showed knowing someone with HBV was the only predictor for screening. Despite guidelines for HBV screening, only half of the Asian Americans surveyed had been screened. Increasing awareness among PCPs is needed to increase HBV screening in this population.

Predicting the effect of ionising radiation on biological populations: testing of a non-linear Leslie model applied to a small mammal population

International Nuclear Information System (INIS)

Monte, Luigi

2013-01-01

The present work describes the application of a non-linear Leslie model for predicting the effects of ionising radiation on wild populations. The model assumes that, for protracted chronic irradiation, the effect-dose relationship is linear. In particular, the effects of radiation are modelled by relating the increase in the mortality rates of the individuals to the dose rates through a proportionality factor C. The model was tested using independent data and information from a series of experiments that were aimed at assessing the response to radiation of wild populations of meadow voles and whose results were described in the international literature. The comparison of the model results with the data selected from the above mentioned experiments showed that the model overestimated the detrimental effects of radiation on the size of irradiated populations when the values of C were within the range derived from the median lethal dose (L 50 ) for small mammals. The described non-linear model suggests that the non-expressed biotic potential of the species whose growth is limited by processes of environmental resistance, such as the competition among the individuals of the same or of different species for the exploitation of the available resources, can be a factor that determines a more effective response of population to the radiation effects. -- Highlights: • A model to assess the radiation effects on wild population is described. • The model is based on non-linear Leslie matrix. • The model is applied to small mammals living in an irradiated meadow. • Model output is conservative if effect-dose factor estimated from L 50 is used. • Systemic response to stress of populations in competitive conditions may be more effective

Survey of Small Business Barriers to Department of Defense Contracts

Science.gov (United States)

2017-01-01

the Better Buying Power initiatives is to increase small business participation in Department of Defense contracting. The department has had mixed...create and maintain world-class weapon systems. Department leadership has pushed for increased small business roles and opportunities through the Better...meet. One way to increase small business participation in defense contracts is to focus reform efforts in areas that small businesses perceive as

A Demo-Genetic Analysis of a Small Reintroduced Carnivore Population: The Otter (Lutra lutra in The Netherlands

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Maelle Seignobosc

2011-01-01

Full Text Available Assessing the viability of reintroduced animal populations is a complicated task. Reintroductions are usually carried out with a small number of individuals, thereby, limiting the possibilities for monitoring because of the possible negative effects of intensive monitoring on survival and reproduction. Moreover, reintroduction studies are part of a socioeconomic interplay of forces, thereby, also limiting monitoring possibilities. Also, knowledge of population demography and abundance can be incomplete or unattainable. Here, we illustrate how we combined traditional telemetry and novel non-invasive genetic methodology to construct a detailed life table of a small reintroduced otter population in The Netherlands. Combining an appropriate capture-mark-recapture framework with a matrix modelling approach provides, in general, useful insights for such populations. The data indicated that (i male survival is lower than female survival, (ii the reintroduced population is currently growing (estimated λ=1.26: range [1.06, 1.42] and seems viable, (iii increasing adult survival is currently the critical stage at which efforts of field managers should concentrate, and (iv the modelling framework allowed us to determine the boundary conditions for the vital rates under which the population would go extinct. The applied approach directs at measurements that help field managers to implement the right conservation strategy after reintroductions.

Field study plan for alternate barriers

International Nuclear Information System (INIS)

Freeman, H.D.; Gee, G.W.; Relyea, J.F.

1989-05-01

Pacific Northwest Laboratory (PNL) is providing technical assistance in selecting, designing, evaluating, and demonstrating protective barriers. As part of this technical assistance effort, asphalt, clay, and chemical grout will be evaluated for use as alternate barriers. The purpose of the subsurface layer is to reduce the likelihood that extreme events (i.e., 100-year maximum storms, etc.) will cause significant drainage through the barrier. The tests on alternate barriers will include laboratory and field analysis of the subsurface layer performance. This field test plan outlines the activities required to test and design subsurface moisture barriers. The test plan covers activities completed in FY 1988 and planned through FY 1992 and includes a field-scale test of one or more of the alternate barriers to demonstrate full-scale application techniques and to provide performance data on a larger scale. Tests on asphalt, clay, and chemical grout were initiated in FY 1988 in small (30.5 cm diameter) tube-layer lysimeters. The parameters used for testing the materials were different for each one. The tests had to take into account the differences in material characteristics and response to change in conditions, as well as information provided by previous studies. 33 refs., 8 figs., 1 tab

On the kinetic barriers of graphene homo-epitaxy

International Nuclear Information System (INIS)

Zhang, Wei; Yu, Xinke; Xie, Ya-Hong; Cahyadi, Erica; Ratsch, Christian

2014-01-01

The diffusion processes and kinetic barriers of individual carbon adatoms and clusters on graphene surfaces are investigated to provide fundamental understanding of the physics governing epitaxial growth of multilayer graphene. It is found that individual carbon adatoms form bonds with the underlying graphene whereas the interaction between graphene and carbon clusters, consisting of 6 atoms or more, is very weak being van der Waals in nature. Therefore, small carbon clusters are quite mobile on the graphene surfaces and the diffusion barrier is negligibly small (∼6 meV). This suggests the feasibility of high-quality graphene epitaxial growth at very low growth temperatures with small carbon clusters (e.g., hexagons) as carbon source. We propose that the growth mode is totally different from 3-dimensional bulk materials with the surface mobility of carbon hexagons being the highest over graphene surfaces that gradually decreases with further increase in cluster size

Population and community profiles of small mammals inhabiting an abandoned oil refinery

International Nuclear Information System (INIS)

McMurry, S.T.; Lochmiller, R.L.; McBee, K.; Burks, S.L.; Quails, C.W. Jr.

1993-01-01

Mark-recapture techniques were used to assess population and community dynamics of resident small mammals on three contaminated and three reference sites located on or near an abandoned oil refinery in Oklahoma. Contaminated sites included areas adjacent to oil sludge containment and sedimentation pits and a land farm for treating oily sludges. Reference sites were selected based on their ecological similarity to contaminated sites. Small mammals were trapped from January 1991 to August 1992 at eight week intervals except during summer and winter during which traps were checked at 3 week intervals. Diversity was typically highest on toxic sites due primarily to the presence of house mice (Mus musculus). Similarity in small mammal community composition between sites differed most in summer. Cotton rats (Sigmodon hispidus) were the most abundant species on all sites. Reproductive activity of adult female cotton rats and survival of trappable cotton rats did not differ between sites. However, minimum number known alive and recruitment of juveniles was highest on references sites, indicating that in-utero and neonatal survival may differ between reference and contaminated sites

Implementation of renewable energy technologies - Opportunities and barriers. Ghana country study

Energy Technology Data Exchange (ETDEWEB)

Edjekumhene, I.; Atakora, S.B.; Atta-Konadu, R.; Brew-Hammond, A. [Kumasi Inst. og Technology and Environment (Ghana)

2001-07-01

This report presents the experience of Ghana in the development, utilisation and promotion of Renewable Energy Technologies (RETs). The report gives a general overview of the state of RETs, describes past/existing institutional, regulatory and policy framework, identifies key barriers to and opportunities for RETs, and recommends directional changes needed to remove barriers and promote wide-scale adoption of RETs in Ghana. A total of eight RETs - biomass-fired dryers, sawdust stoves, sawdust briquette, biogas, solar crop dryer, solar water heater, solar water pump and small hydro power - are covered in the report. Analyses of barriers to the eight RETs are carried out using a framework approach that categorises barriers into socio-technical, economic and crosscutting barriers. Financial analyses, as opposed to economic analyses, have been carried out for all the selected RETs. The report also incorporates stake holders' perspectives and views on barriers and how they can be removed. Ghana is endowed with several renewable energy resources like solar radiation, small hydro, biomass, and wind. Exploitation of Ghana's renewable energy resources has been carried out under two main policy regimes - PND Law 62 (1983) and the Energy Sector Development Programme (ESDP). Several measures and instruments have been employed in the implementation of renewable energy policies. The main measures used are research and development, information and eduction, and some normative measures (like the passing of PNDC Law 62 and the Energy Commission Law). Some economic instruments, such as subsidies, taxes, pricing, financing and duty waiver/reduction, have been used as well but only to a limited extent. The effective development, implementation and dissemination of all the RETs studied are hampered by several barriers, which can be grouped into three main categories - Socio-technical barriers, economic barriers and crosscutting barriers. Socio-technical barriers refer to

Implementation of renewable energy technologies - Opportunities and barriers. Ghana country study

Energy Technology Data Exchange (ETDEWEB)

Edjekumhene, I; Atakora, S B; Atta-Konadu, R; Brew-Hammond, A [Kumasi Inst. og Technology and Environment (Ghana)

2001-07-01

This report presents the experience of Ghana in the development, utilisation and promotion of Renewable Energy Technologies (RETs). The report gives a general overview of the state of RETs, describes past/existing institutional, regulatory and policy framework, identifies key barriers to and opportunities for RETs, and recommends directional changes needed to remove barriers and promote wide-scale adoption of RETs in Ghana. A total of eight RETs - biomass-fired dryers, sawdust stoves, sawdust briquette, biogas, solar crop dryer, solar water heater, solar water pump and small hydro power - are covered in the report. Analyses of barriers to the eight RETs are carried out using a framework approach that categorises barriers into socio-technical, economic and crosscutting barriers. Financial analyses, as opposed to economic analyses, have been carried out for all the selected RETs. The report also incorporates stake holders' perspectives and views on barriers and how they can be removed. Ghana is endowed with several renewable energy resources like solar radiation, small hydro, biomass, and wind. Exploitation of Ghana's renewable energy resources has been carried out under two main policy regimes - PND Law 62 (1983) and the Energy Sector Development Programme (ESDP). Several measures and instruments have been employed in the implementation of renewable energy policies. The main measures used are research and development, information and eduction, and some normative measures (like the passing of PNDC Law 62 and the Energy Commission Law). Some economic instruments, such as subsidies, taxes, pricing, financing and duty waiver/reduction, have been used as well but only to a limited extent. The effective development, implementation and dissemination of all the RETs studied are hampered by several barriers, which can be grouped into three main categories - Socio-technical barriers, economic barriers and crosscutting barriers. Socio-technical barriers refer to resource

Modelling the endothelial blood-CNS barriers: a method for the production of robust in vitro models of the rat blood-brain barrier and blood-spinal cord barrier.

Science.gov (United States)

Watson, P Marc D; Paterson, Judy C; Thom, George; Ginman, Ulrika; Lundquist, Stefan; Webster, Carl I

2013-06-18

Modelling the blood-CNS barriers of the brain and spinal cord in vitro continues to provide a considerable challenge for research studying the passage of large and small molecules in and out of the central nervous system, both within the context of basic biology and for pharmaceutical drug discovery. Although there has been considerable success over the previous two decades in establishing useful in vitro primary endothelial cell cultures from the blood-CNS barriers, no model fully mimics the high electrical resistance, low paracellular permeability and selective influx/efflux characteristics of the in vivo situation. Furthermore, such primary-derived cultures are typically labour-intensive and generate low yields of cells, limiting scope for experimental work. We thus aimed to establish protocols for the high yield isolation and culture of endothelial cells from both rat brain and spinal cord. Our aim was to optimise in vitro conditions for inducing phenotypic characteristics in these cells that were reminiscent of the in vivo situation, such that they developed into tight endothelial barriers suitable for performing investigative biology and permeability studies. Brain and spinal cord tissue was taken from the same rats and used to specifically isolate endothelial cells to reconstitute as in vitro blood-CNS barrier models. Isolated endothelial cells were cultured to expand the cellular yield and then passaged onto cell culture inserts for further investigation. Cell culture conditions were optimised using commercially available reagents and the resulting barrier-forming endothelial monolayers were characterised by functional permeability experiments and in vitro phenotyping by immunocytochemistry and western blotting. Using a combination of modified handling techniques and cell culture conditions, we have established and optimised a protocol for the in vitro culture of brain and, for the first time in rat, spinal cord endothelial cells. High yields of both CNS

Approaches for cytogenetic and molecular analyses of small flow-sorted cell populations from childhood leukemia bone marrow samples

DEFF Research Database (Denmark)

Obro, Nina Friesgaard; Madsen, Hans O.; Ryder, Lars Peter

2011-01-01

defined cell populations with subsequent analyses of leukemia-associated cytogenetic and molecular marker. The approaches described here optimize the use of the same tube of unfixed, antibody-stained BM cells for flow-sorting of small cell populations and subsequent exploratory FISH and PCR-based analyses....

Microsatellites Reveal Genetic Homogeneity among Outbreak Populations of Crown-of-Thorns Starfish (Acanthaster cf. solaris) on Australia’s Great Barrier Reef

KAUST Repository

Harrison, Hugo

2017-03-10

Specific patterns in the initiation and spread of reef-wide outbreaks of crown-of-thorns starfish are important, both to understand potential causes (or triggers) of outbreaks and to develop more effective and highly targeted management and containment responses. Using analyses of genetic diversity and structure (based on 17 microsatellite loci), this study attempted to resolve the specific origin for recent outbreaks of crown-of-thorns on Australia’s Great Barrier Reef (GBR). We assessed the genetic structure amongst 2705 starfish collected from 13 coral reefs in four regions that spanned ~1000 km of the GBR. Our results indicate that populations sampled across the full length of the GBR are genetically homogeneous (G’ST = −0.001; p = 0.948) with no apparent genetic structure between regions. Approximate Bayesian computational analyses suggest that all sampled populations had a common origin and that current outbreaking populations of crown-of-thorns starfish (CoTS) in the Swains are not independent of outbreak populations in the northern GBR. Despite hierarchical sampling and large numbers of CoTS genotyped from individual reefs and regions, limited genetic structure meant we were unable to determine a putative source population for the current outbreak of CoTS on the GBR. The very high genetic homogeneity of sampled populations and limited evidence of inbreeding indicate rapid expansion in population size from multiple, undifferentiated latent populations.

Microsatellites Reveal Genetic Homogeneity among Outbreak Populations of Crown-of-Thorns Starfish (Acanthaster cf. solaris) on Australia’s Great Barrier Reef

KAUST Repository

Harrison, Hugo; Pratchett, Morgan; Messmer, Vanessa; Saenz-Agudelo, Pablo; Berumen, Michael L.

2017-01-01

Specific patterns in the initiation and spread of reef-wide outbreaks of crown-of-thorns starfish are important, both to understand potential causes (or triggers) of outbreaks and to develop more effective and highly targeted management and containment responses. Using analyses of genetic diversity and structure (based on 17 microsatellite loci), this study attempted to resolve the specific origin for recent outbreaks of crown-of-thorns on Australia’s Great Barrier Reef (GBR). We assessed the genetic structure amongst 2705 starfish collected from 13 coral reefs in four regions that spanned ~1000 km of the GBR. Our results indicate that populations sampled across the full length of the GBR are genetically homogeneous (G’ST = −0.001; p = 0.948) with no apparent genetic structure between regions. Approximate Bayesian computational analyses suggest that all sampled populations had a common origin and that current outbreaking populations of crown-of-thorns starfish (CoTS) in the Swains are not independent of outbreak populations in the northern GBR. Despite hierarchical sampling and large numbers of CoTS genotyped from individual reefs and regions, limited genetic structure meant we were unable to determine a putative source population for the current outbreak of CoTS on the GBR. The very high genetic homogeneity of sampled populations and limited evidence of inbreeding indicate rapid expansion in population size from multiple, undifferentiated latent populations.

Shakeoff Ionization near the Coulomb Barrier Energy

Science.gov (United States)

Sharma, Prashant; Nandi, T.

2017-11-01

We measure the projectile K x-ray spectra as a function of the beam energies around the Coulomb barrier in different collision systems. The energy is scanned in small steps around the barrier aiming to explore the nuclear effects on the elastically scattered projectile ions. The variation of the projectile x-ray energy with the ion-beam energies exhibits an unusual increase in between the interaction barrier and fusion barrier energies. This additional contribution to the projectile ionization can be attributed to the shakeoff of outer-shell electrons of the projectile ions due to the sudden nuclear recoil (˜10-21 sec ) caused by the attractive nuclear potential, which gets switched on near the interaction barrier energy. In the sudden approximation limit, the theoretical shakeoff probability calculation due to the nuclear recoil explains the observed data well. In addition to its fundamental interest, such processes can play a significant role in dark matter detection through the possible mechanism of x-ray emissions, where the weakly interacting massive particle-nucleus elastic scattering can lead to the nuclear-recoil-induced inner-shell vacancy creations. Furthermore, the present work may provide new prospects for atomic physics research at barrier energies as well as provide a novel technique to perform barrier distribution studies for two-body systems.

Response of small mammal populations to fuel treatment and precipitation in a ponderosa pine forest, New Mexico

Science.gov (United States)

Karen E. Bagne; Deborah M. Finch

2009-01-01

Mechanical and fire treatments are commonly used to reduce fuels where land use practices have encouraged accumulation of woody debris and high densities of trees. Treatments focus on restoration of vegetation structure, but will also affect wildlife populations. Small mammal populations were monitored before and after dense tree stands were thinned on 2,800 ha in NM,...

Adhesion barriers at cesarean delivery: advertising compared with the evidence.

Science.gov (United States)

Albright, Catherine M; Rouse, Dwight J

2011-07-01

Cesarean delivery, the most common surgery performed in the United States, is complicated by adhesion formation in 24-73% of cases. Because adhesions have potential sequelae, different synthetic adhesion barriers are currently heavily marketed as a means of reducing adhesion formation resultant from cesarean delivery. However, their use for this purpose has been studied in only two small, nonblinded and nonrandomized trials, both of which were underpowered and subject to bias. Neither demonstrated improvement in meaningful clinical outcomes. In the only cost-effectiveness analysis of adhesion barriers to date, the use of synthetic adhesion barriers was cost-effective only when the subsequent rate of small bowel obstruction was at least 2.4%, a rate far higher than that associated with cesarean delivery. In fact, intra-abdominal adhesions from prior cesarean delivery rarely cause maternal harm and have not been demonstrated to adversely affect perinatal outcome. Based on our review of the available literature, we think the use of adhesion barriers at the time of cesarean delivery would be ill-advised at the present time.

Effect of disposable infection control barriers on light output from dental curing lights.

Science.gov (United States)

Scott, Barbara A; Felix, Corey A; Price, Richard B T

2004-02-01

To prevent contamination of the light guide on a dental curing light, barriers such as disposable plastic wrap or covers may be used. This study compared the effect of 3 disposable barriers on the spectral output and power density from a curing light. The hypothesis was that none of the barriers would have a significant clinical effect on the spectral output or the power density from the curing light. Three disposable barriers were tested against a control (no barrier). The spectra and power from the curing light were measured with a spectrometer attached to an integrating sphere. The measurements were repeated on 10 separate occasions in a random sequence for each barrier. Analysis of variance (ANOVA) followed by Fisher's protected least significant difference test showed that the power density was significantly less than control (by 2.4% to 6.1%) when 2 commercially available disposable barriers were used (p 0.05). The effect of each of the barriers on the power output was small and probably clinically insignificant. ANOVA comparisons of mean peak wavelength values indicated that none of the barriers produced a significant shift in the spectral output relative to the control ( p > 0.05). Two of the 3 disposable barriers produced a significant reduction in power density from the curing light. This drop in power was small and would probably not adversely affect the curing of composite resin. None of the barriers acted as light filters.

Can small wildlife conservancies maintain genetically stable populations of large mammals? Evidence for increased genetic drift in geographically restricted populations of Cape buffalo in East Africa

DEFF Research Database (Denmark)

Heller, R; Okello, J B A; Siegismund, H

2010-01-01

populations, the level of genetic differentiation found here is comparable to that among pan-African populations. Overall, correlations between conservancy area and indices of genetic diversity suggest buffalo populations inhabiting small parks are showing signs of genetic erosion, stressing the need for more......The Cape buffalo (Syncerus caffer caffer) is one of the dominant and most widespread herbivores in sub-Saharan Africa. High levels of genetic diversity and exceptionally low levels of population differentiation have been found in the Cape buffalo compared to other African savannah ungulates...... active management of such populations. Our findings raise concerns about the future of other African savannah ungulates with lower population sizes and inferior dispersal capabilities compared with the buffalo....

Self-reported financial barriers to care among patients with cardiovascular-related chronic conditions.

Science.gov (United States)

Campbell, David J T; King-Shier, Kathryn; Hemmelgarn, Brenda R; Sanmartin, Claudia; Ronksley, Paul E; Weaver, Robert G; Tonelli, Marcello; Hennessy, Deirdre; Manns, Braden J

2014-05-01

People with chronic conditions who do not achieve therapeutic targets have a higher risk of adverse health outcomes. Failure to meet these targets may be due to a variety of barriers. This article examines self-reported financial barriers to health care among people with cardiovascular-related chronic conditions. A population-based survey was administered to western Canadians with cardiovascular-related chronic conditions (n = 1,849). Associations between self-reported financial barriers and statin use, the likelihood of stopping use of prescribed medications, and emergency department visits or hospitalizations were assessed. More than 10% respondents reported general financial barriers (12%) and lack of drug insurance (14%); 4% reported financial barriers to accessing medications. Emergency department visits or hospitalizations were 70% more likely among those reporting a general financial barrier. Those reporting a financial barrier to medications were 50% less likely to take statins and three times more likely to stop using prescribed medications. Individuals without drug insurance were nearly 30% less likely to take statins. In this population, self-reported financial barriers were associated with lower medication use and increased likelihood of emergency department visits or hospitalization.

Adherence to tuberculosis care in Canadian Aboriginal populations, Part 1: definition, measurement, responsibility, barriers.

Science.gov (United States)

Orr, Pamela

2011-04-01

In a 2-part series, the current literature with respect to adherence to tuberculosis care among Canadian Aboriginal populations is reviewed. In the current paper, which comprises part 1 of this review, adherence is defined, and methods of measurement, issues of responsibility and potential barriers to adherence are explored. Study design. Literature review. A systematic search and analytic review of relevant studies was undertaken, including an online search of electronic databases (PubMed, PsychINFO, MEDLINE, Native Health Database, Scopus, Social Science Citation Index) and publications by governmental and non-governmental agencies. Poor adherence to therapy for TB disease is the most common cause of initial treatment failure and of disease relapse worldwide. Adherence to care for TB disease is necessary for the health of both the affected individual and society as a whole. Adherence is a task-specific behaviour that is not inherent to ethnic identity. The term applies only when common agreement over a care plan has been reached between patient and provider. The International Standards for Tuberculosis Care and the Patients Charter outline the responsibilities for adherence on the part of both patients and providers. For Canadian Aboriginals, barriers to adherence may derive from a complex interaction between the health system, personal factors and social factors, which may include dysfunctional acute and public health systems, dissonant (between health care provider and patient) belief systems, concurrent co-morbidities and life stressors, poverty and social stigma. Adherence is a task-specific behaviour, not a personality trait. It is influenced by the interaction of systemic, personal and societal factors. These factors must be understood within the historical experience of TB and the cultural meaning of health and illness among Indigenous Canadians.

Addressing Youth Employment Through Micro- and Small ...

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

... Employment Through Micro- and Small-Enterprise Development in Ethiopia. Youth unemployment has emerged as a key challenge facing developing and ... to youth to start small businesses and to youth-led micro- and small-enterprises. ... the barriers and challenges young Ethiopian men and women face in the labour ...

Reducing Transaction Costs for Energy Efficiency Investments and Analysis of Economic Risk Associated With Building Performance Uncertainties: Small Buildings and Small Portfolios Program

Energy Technology Data Exchange (ETDEWEB)

Langner, R.; Hendron, B.; Bonnema, E.

2014-08-01

The small buildings and small portfolios (SBSP) sector face a number of barriers that inhibit SBSP owners from adopting energy efficiency solutions. This pilot project focused on overcoming two of the largest barriers to financing energy efficiency in small buildings: disproportionately high transaction costs and unknown or unacceptable risk. Solutions to these barriers can often be at odds, because inexpensive turnkey solutions are often not sufficiently tailored to the unique circumstances of each building, reducing confidence that the expected energy savings will be achieved. To address these barriers, NREL worked with two innovative, forward-thinking lead partners, Michigan Saves and Energi, to develop technical solutions that provide a quick and easy process to encourage energy efficiency investments while managing risk. The pilot project was broken into two stages: the first stage focused on reducing transaction costs, and the second stage focused on reducing performance risk. In the first stage, NREL worked with the non-profit organization, Michigan Saves, to analyze the effects of 8 energy efficiency measures (EEMs) on 81 different baseline small office building models in Holland, Michigan (climate zone 5A). The results of this analysis (totaling over 30,000 cases) are summarized in a simple spreadsheet tool that enables users to easily sort through the results and find appropriate small office EEM packages that meet a particular energy savings threshold and are likely to be cost-effective.

The effect of multiple paternity on genetic diversity of small populations during and after colonisation.

Directory of Open Access Journals (Sweden)

Marina Rafajlović

Full Text Available Genetic variation within and among populations is influenced by the genetic content of the founders and the migrants following establishment. This is particularly true if populations are small, migration rate low and habitats arranged in a stepping-stone fashion. Under these circumstances the level of multiple paternity is critical since multiply mated females bring more genetic variation into founder groups than single mated females. One such example is the marine snail Littorina saxatilis that during postglacial times has invaded mainland refuge areas and thereafter small islands emerging due to isostatic uplift by occasional rafting of multiply mated females. We modelled effects of varying degrees of multiple paternity on the genetic variation of island populations colonised by the founders spreading from the mainland, by quantifying the population heterozygosity during both the transient colonisation process, and after a steady state (with migration has been reached. During colonisation, multiple mating by [Formula: see text] males increased the heterozygosity by [Formula: see text] in comparison with single paternity, while in the steady state the increase was [Formula: see text] compared with single paternity. In the steady state the increase of heterozygosity due to multiple paternity is determined by a corresponding increase in effective population size. During colonisation, by contrast, the increase in heterozygosity is larger and it cannot be explained in terms of the effective population size alone. During the steady-state phase bursts of high genetic variation spread through the system, and far from the mainland this led to short periods of high diversity separated by long periods of low diversity. The size of these fluctuations was boosted by multiple paternity. We conclude that following glacial periods of extirpation, recolonization of isolated habitats by this species has been supported by its high level of multiple paternity.

The Effect of Multiple Paternity on Genetic Diversity of Small Populations during and after Colonisation

KAUST Repository

Rafajlović, Marina

2013-10-28

Genetic variation within and among populations is influenced by the genetic content of the founders and the migrants following establishment. This is particularly true if populations are small, migration rate low and habitats arranged in a stepping-stone fashion. Under these circumstances the level of multiple paternity is critical since multiply mated females bring more genetic variation into founder groups than single mated females. One such example is the marine snail Littorina saxatilis that during postglacial times has invaded mainland refuge areas and thereafter small islands emerging due to isostatic uplift by occasional rafting of multiply mated females. We modelled effects of varying degrees of multiple paternity on the genetic variation of island populations colonised by the founders spreading from the mainland, by quantifying the population heterozygosity during both the transient colonisation process, and after a steady state (with migration) has been reached. During colonisation, multiple mating by 2-10 males increased the heterozygosity by 10-300% in comparison with single paternity, while in the steady state the increase was 10-50% compared with single paternity. In the steady state the increase of heterozygosity due to multiple paternity is determined by a corresponding increase in effective population size. During colonisation, by contrast, the increase in heterozygosity is larger and it cannot be explained in terms of the effective population size alone. During the steady-state phase bursts of high genetic variation spread through the system, and far from the mainland this led to short periods of high diversity separated by long periods of low diversity. The size of these fluctuations was boosted by multiple paternity. We conclude that following glacial periods of extirpation, recolonization of isolated habitats by this species has been supported by its high level of multiple paternity. 2013 Rafajlovi? et al.

Barriers to family planning and contraception uptake in sub-Saharan Africa: a systematic review.

Science.gov (United States)

Haider, Taj L; Sharma, Manoj

This review assessed barriers to uptake of family planning and contraceptive services among women in sub-Saharan Africa. Included were studies: (1) published in the English; (2) between the years January 2010 and July 2012; (3) that measure barriers to family planning/contraceptive methods; and (4) that use any quantitative or qualitative study design. Eleven studies fitting the inclusion criteria were reviewed. The major barriers found to prevent uptake of services included cultural and societal pressure on women, socioeconomic status, financial barriers, and regional barriers associated with lack of access to services. Due to the diversity of the populations in sub-Saharan Africa, it is clear that a one-size-fits-all approach will not be efficacious; rather, a strategy that takes into account cultural and societal norms for the population of interest is better.

The Barrier code for predicting long-term concrete performance

International Nuclear Information System (INIS)

Shuman, R.; Rogers, V.C.; Shaw, R.A.

1989-01-01

There are numerous features incorporated into a LLW disposal facility that deal directly with critical safety objectives required by the NRC in 10 CFR 61. Engineered barriers or structures incorporating concrete are commonly being considered for waste disposal facilities. The Barrier computer code calculates the long-term degradation of concrete structures in LLW disposal facilities. It couples this degradation with water infiltration into the facility, nuclide leaching from the waste, contaminated water release from the facility, and associated doses to members of the critical population group. The concrete degradation methodology of Barrier is described

Unequal socioeconomic distribution of the primary care workforce: whole-population small area longitudinal study.

Science.gov (United States)

Asaria, Miqdad; Cookson, Richard; Fleetcroft, Robert; Ali, Shehzad

2016-01-19

To measure changes in socioeconomic inequality in the distribution of family physicians (general practitioners (GPs)) relative to need in England from 2004/2005 to 2013/2014. Whole-population small area longitudinal data linkage study. England from 2004/2005 to 2013/2014. 32,482 lower layer super output areas (neighbourhoods of 1500 people on average). Slope index of inequality (SII) between the most and least deprived small areas in annual full-time equivalent GPs (FTE GPs) per 100,000 need adjusted population. In 2004/2005, inequality in primary care supply as measured by the SII in FTE GPs was 4.2 (95% CI 3.1 to 5.3) GPs per 100,000. By 2013/2014, this SII had fallen to -0.7 (95% CI -2.5 to 1.1) GPs per 100,000. The number of FTE GPs per 100,000 serving the most deprived fifth of small areas increased over this period from 54.0 to 60.5, while increasing from 57.2 to 59.9 in the least deprived fifth, so that by the end of the study period there were more GPs per 100,000 need adjusted population in the most deprived areas than in the least deprived. The increase in GP supply in the most deprived fifth of neighbourhoods was larger in areas that received targeted investment for establishing new practices under the 'Equitable Access to Primary Medical Care'. There was a substantial reduction in socioeconomic inequality in family physician supply associated with national policy. This policy may not have completely eliminated socioeconomic inequality in family physician supply since existing need adjustment formulae do not fully capture the additional burden of multimorbidity in deprived neighbourhoods. The small area approach introduced in this study can be used routinely to monitor socioeconomic inequality of access to primary care and to indicate workforce shortages in particular neighbourhoods. http://creativecommons.org/licenses/by/4.0. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

Disease management programs: barriers and benefits.

Science.gov (United States)

Magnezi, Racheli; Kaufman, Galit; Ziv, Arnona; Kalter-Leibovici, Ofra; Reuveni, Haim

2013-04-01

The healthcare system in Israel faces difficulties similar to those of most industrialized countries, including limited resources, a growing chronically ill population, and demand for high quality care. Disease management programs (DMPs) for patients with a chronic illness aim to alleviate some of these problems, primarily by improving patient self-management skills and quality of care. This study surveyed the opinions of senior healthcare administrators regarding barriers, benefits, and support for implementing DMPs. Cross-sectional survey. A 21-item questionnaire was self-completed by 87 of 105 (83%) healthcare administrators included in the study. Participants were 65.5% male and 47% physicians, 25.3% nurses, 17.3% administrators, and 10.3% other healthcare professionals. The main perceived benefit of DMPs among all respondents was improving quality of care. Other benefits noted were better contact with patients (81.6%) and better compliance with treatment (75.9%). Efficient long-term utilization of system resources was perceived as a benefit by only 58.6%. The main perceived barriers to implementing DMPs were lack of budgetary resources (69%) and increased time required versus financial compensation received (63.2%). The benefits of DMPs were patient oriented; barriers were perceived as financial and limiting professional autonomy. Information regarding long-term benefits (better patient outcomes) that ultimately provide better value for the system versus short-term barriers (increased costs and expenditures of time without compensation) might encourage the implementation of DMPs in countries faced with a growing population of patients with at least 1 chronic illness.

Lynch syndrome: barriers to and facilitators of screening and disease management.

Science.gov (United States)

Watkins, Kathy E; Way, Christine Y; Fiander, Jacqueline J; Meadus, Robert J; Esplen, Mary Jane; Green, Jane S; Ludlow, Valerie C; Etchegary, Holly A; Parfrey, Patrick S

2011-09-07

Lynch syndrome is a hereditary cancer with confirmed carriers at high risk for colorectal (CRC) and extracolonic cancers. The purpose of the current study was to develop a greater understanding of the factors influencing decisions about disease management post-genetic testing. The study used a grounded theory approach to data collection and analysis as part of a multiphase project examining the psychosocial and behavioral impact of predictive DNA testing for Lynch syndrome. Individual and small group interviews were conducted with individuals from 10 families with the MSH2 intron 5 splice site mutation or exon 8 deletion. The data from confirmed carriers (n = 23) were subjected to re-analysis to identify key barriers to and/or facilitators of screening and disease management. Thematic analysis identified personal, health care provider and health care system factors as dominant barriers to and/or facilitators of managing Lynch syndrome. Person-centered factors reflect risk perceptions and decision-making, and enduring screening/disease management. The perceived knowledge and clinical management skills of health care providers also influenced participation in recommended protocols. The health care system barriers/facilitators are defined in terms of continuity of care and coordination of services among providers. Individuals with Lynch syndrome often encounter multiple barriers to and facilitators of disease management that go beyond the individual to the provider and health care system levels. The current organization and implementation of health care services are inadequate. A coordinated system of local services capable of providing integrated, efficient health care and follow-up, populated by providers with knowledge of hereditary cancer, is necessary to maintain optimal health.

Lynch syndrome: barriers to and facilitators of screening and disease management

Directory of Open Access Journals (Sweden)

Watkins Kathy E

2011-09-01

Full Text Available Abstract Background Lynch syndrome is a hereditary cancer with confirmed carriers at high risk for colorectal (CRC and extracolonic cancers. The purpose of the current study was to develop a greater understanding of the factors influencing decisions about disease management post-genetic testing. Methods The study used a grounded theory approach to data collection and analysis as part of a multiphase project examining the psychosocial and behavioral impact of predictive DNA testing for Lynch syndrome. Individual and small group interviews were conducted with individuals from 10 families with the MSH2 intron 5 splice site mutation or exon 8 deletion. The data from confirmed carriers (n = 23 were subjected to re-analysis to identify key barriers to and/or facilitators of screening and disease management. Results Thematic analysis identified personal, health care provider and health care system factors as dominant barriers to and/or facilitators of managing Lynch syndrome. Person-centered factors reflect risk perceptions and decision-making, and enduring screening/disease management. The perceived knowledge and clinical management skills of health care providers also influenced participation in recommended protocols. The health care system barriers/facilitators are defined in terms of continuity of care and coordination of services among providers. Conclusions Individuals with Lynch syndrome often encounter multiple barriers to and facilitators of disease management that go beyond the individual to the provider and health care system levels. The current organization and implementation of health care services are inadequate. A coordinated system of local services capable of providing integrated, efficient health care and follow-up, populated by providers with knowledge of hereditary cancer, is necessary to maintain optimal health.

Fusion barrier distributions - What have we learned?

International Nuclear Information System (INIS)

Hinde, D. J.; Dasgupta, M.

1998-01-01

The study of nuclear fusion received a strong impetus from the realisation that an experimental fusion barrier distribution could be determined from precisely measured fusion cross-sections. Experimental data for different reactions have shown in the fusion barrier distributions clear signatures of a range of nuclear excitations, for example the effects of static quadrupole and hexadecapole deformations, single- and double-phonon states, transfer of nucleons, and high-lying excited states. The improved understanding of fusion barrier distributions allows more reliable prediction of fusion angular momentum distributions, which aids interpretation of fission probabilities and fission anisotropies, and understanding of the population of super-deformed bands for nuclear structure studies. Studies of the relationship between the fusion barrier distribution and the extra-push energy should improve our understanding of the mechanism of the extra-push effect, and may help to predict new ways of forming very heavy or super-heavy nuclei

Free energy barriers to evaporation of water in hydrophobic confinement.

Science.gov (United States)

Sharma, Sumit; Debenedetti, Pablo G

2012-11-08

We use umbrella sampling Monte Carlo and forward and reverse forward flux sampling (FFS) simulation techniques to compute the free energy barriers to evaporation of water confined between two hydrophobic surfaces separated by nanoscopic gaps, as a function of the gap width, at 1 bar and 298 K. The evaporation mechanism for small (1 × 1 nm(2)) surfaces is found to be fundamentally different from that for large (3 × 3 nm(2)) surfaces. In the latter case, the evaporation proceeds via the formation of a gap-spanning tubular cavity. The 1 × 1 nm(2) surfaces, in contrast, are too small to accommodate a stable vapor cavity. Accordingly, the associated free energy barriers correspond to the formation of a critical-sized cavity for sufficiently large confining surfaces, and to complete emptying of the gap region for small confining surfaces. The free energy barriers to evaporation were found to be of O(20kT) for 14 Å gaps, and to increase by approximately ~5kT with every 1 Å increase in the gap width. The entropy contribution to the free energy of evaporation was found to be independent of the gap width.

The Blood-Brain Barrier: An Engineering Perspective

Directory of Open Access Journals (Sweden)

Andrew eWong

2013-08-01

Full Text Available It has been more than 100 years since Paul Ehrlich reported that various water-soluble dyes injected into the circulation did not enter the brain. Since Ehrlich’s first experiments, only a small number of molecules, such as alcohol and caffeine have been found to cross the blood-brain barrier, and it remains the major roadblock to treatment of many central nervous system diseases. At the same time, many central nervous system diseases are associated with disruption of the blood-brain barrier that can lead to changes in permeability, modulation of immune cell transport, and trafficking of pathogens into the brain. Therefore advances in our understanding of the structure and function of the blood-brain barrier are key to advances in treatment of a wide range of central nervous system diseases. Over the past 10 years it has become recognized that the blood-brain barrier is a complex dynamic system that involves biomechanical and biochemical signaling between the vascular system and the brain. Here we reconstruct the structure, function, and transport properties of the blood-brain barrier from an engineering perspective. New insight into the physics of the blood-brain barrier could ultimately lead to clinical advances in the treatment of central nervous system diseases.

Small mammal populations of an agroecosystem in the Atlantic Forest domain, southeastern Brazil

Directory of Open Access Journals (Sweden)

PS. D’Andrea

Full Text Available This study reports 2 years of the population dynamics and reproduction of a small mammal community using the removal method. The study was conducted in a rural area of the Atlantic Forest, in Sumidouro, Rio de Janeiro State, Brazil. The population sizes, age structure and reproduction were studied for the four most common species in the study area. The overall diversity was 1.67 and ranged between 0.8 to 1.67. The species richness was 13 considering the whole study. The most abundant species were the rodents Nectomys squamipes (n = 133, Akodon cursor (n = 74, Oligoryzomys nigripes (n = 25 and the marsupials Didelphis aurita (n = 58 and Philander frenatus (n = 50. Seven other rodents were captured once: Necromys lasiurus, Akodon montensis, Sooretamys angouya, Oecomys catherine, Oxymycterus judex, Euryzygomatomys spinosus and Trinomys iheringi. There were higher peaks for diversity and species richness during the winter (dry months, probably due to higher food availability. The marsupials had a seasonal reproduction with highest population sizes at the end of the rainy seasons. Nectomys squamipes reproduced mostly during rainy periods. Akodon cursor reproduced predominantly in the winter with the highest population peaks occurring during this season. The analysis of the population dynamics of the rodent species indicated that no species behaved as an agricultural pest, probably due to the heterogeneous landscape of high rotativity of vegetable cultivation. Rodent populations were more susceptible to the removal procedure than marsupial ones.

Near-Earth-object survey progress and population of small near-Earth asteroids

Science.gov (United States)

Harris, A.

2014-07-01

Estimating the total population vs. size of NEAs and the completion of surveys is the same thing since the total population is just the number discovered divided by the estimated completion. I review the method of completion estimation based on ratio of re-detected objects to total detections (known plus new discoveries). The method is quite general and can be used for population estimations of all sorts, from wildlife to various classes of solar system bodies. Since 2001, I have been making estimates of population and survey progress approximately every two years. Plotted below, left, is my latest estimate, including NEA discoveries up to August, 2012. I plan to present an update at the meeting. All asteroids of a given size are not equally easy to detect because of specific orbital geometries. Thus a model of the orbital distribution is necessary, and computer simulations using those orbits need to establish the relation between the raw re-detection ratio and the actual completion fraction. This can be done for any sub-group population, allowing to estimate the population of a subgroup and the expected current completion. Once a reliable survey computer model has been developed and ''calibrated'' with respect to actual survey re-detections versus size, it can be extrapolated to smaller sizes to estimate completion even at very small size where re-detections are rare or even zero. I have recently investigated the subgroup of extremely low encounter velocity NEAs, the class of interest for the Asteroid Redirect Mission (ARM), recently proposed by NASA. I found that asteroids of diameter ˜ 10 m with encounter velocity with the Earth lower than 2.5 km/sec are detected by current surveys nearly 1,000 times more efficiently than the general background of NEAs of that size. Thus the current completion of these slow relative velocity objects may be around 1%, compared to 10^{-6} for that size objects of the general velocity distribution. Current surveys are nowhere near

Population Genetic Structure of the Tropical Two-Wing Flyingfish (Exocoetus volitans.

Directory of Open Access Journals (Sweden)

Eric A Lewallen

Full Text Available Delineating populations of pantropical marine fish is a difficult process, due to widespread geographic ranges and complex life history traits in most species. Exocoetus volitans, a species of two-winged flyingfish, is a good model for understanding large-scale patterns of epipelagic fish population structure because it has a circumtropical geographic range and completes its entire life cycle in the epipelagic zone. Buoyant pelagic eggs should dictate high local dispersal capacity in this species, although a brief larval phase, small body size, and short lifespan may limit the dispersal of individuals over large spatial scales. Based on these biological features, we hypothesized that E. volitans would exhibit statistically and biologically significant population structure defined by recognized oceanographic barriers. We tested this hypothesis by analyzing cytochrome b mtDNA sequence data (1106 bps from specimens collected in the Pacific, Atlantic and Indian oceans (n = 266. AMOVA, Bayesian, and coalescent analytical approaches were used to assess and interpret population-level genetic variability. A parsimony-based haplotype network did not reveal population subdivision among ocean basins, but AMOVA revealed limited, statistically significant population structure between the Pacific and Atlantic Oceans (ΦST = 0.035, p<0.001. A spatially-unbiased Bayesian approach identified two circumtropical population clusters north and south of the Equator (ΦST = 0.026, p<0.001, a previously unknown dispersal barrier for an epipelagic fish. Bayesian demographic modeling suggested the effective population size of this species increased by at least an order of magnitude ~150,000 years ago, to more than 1 billion individuals currently. Thus, high levels of genetic similarity observed in E. volitans can be explained by high rates of gene flow, a dramatic and recent population expansion, as well as extensive and consistent dispersal throughout the geographic

Population Genetic Structure of the Tropical Two-Wing Flyingfish (Exocoetus volitans)

Science.gov (United States)

Lewallen, Eric A.; Bohonak, Andrew J.; Bonin, Carolina A.; van Wijnen, Andre J.; Pitman, Robert L.; Lovejoy, Nathan R.

2016-01-01

Delineating populations of pantropical marine fish is a difficult process, due to widespread geographic ranges and complex life history traits in most species. Exocoetus volitans, a species of two-winged flyingfish, is a good model for understanding large-scale patterns of epipelagic fish population structure because it has a circumtropical geographic range and completes its entire life cycle in the epipelagic zone. Buoyant pelagic eggs should dictate high local dispersal capacity in this species, although a brief larval phase, small body size, and short lifespan may limit the dispersal of individuals over large spatial scales. Based on these biological features, we hypothesized that E. volitans would exhibit statistically and biologically significant population structure defined by recognized oceanographic barriers. We tested this hypothesis by analyzing cytochrome b mtDNA sequence data (1106 bps) from specimens collected in the Pacific, Atlantic and Indian oceans (n = 266). AMOVA, Bayesian, and coalescent analytical approaches were used to assess and interpret population-level genetic variability. A parsimony-based haplotype network did not reveal population subdivision among ocean basins, but AMOVA revealed limited, statistically significant population structure between the Pacific and Atlantic Oceans (ΦST = 0.035, p<0.001). A spatially-unbiased Bayesian approach identified two circumtropical population clusters north and south of the Equator (ΦST = 0.026, p<0.001), a previously unknown dispersal barrier for an epipelagic fish. Bayesian demographic modeling suggested the effective population size of this species increased by at least an order of magnitude ~150,000 years ago, to more than 1 billion individuals currently. Thus, high levels of genetic similarity observed in E. volitans can be explained by high rates of gene flow, a dramatic and recent population expansion, as well as extensive and consistent dispersal throughout the geographic range of the

Autoradiographic study of the permeability characteristics of the small intestine

Energy Technology Data Exchange (ETDEWEB)

Kingham, J G.C.; Baker, J H; Loehry, C A [Royal Victoria Hospital, Bournemouth (UK)

1978-02-01

This autoradiographic study demonstrates the distribution of a range of small solutes and macromolecules in the mucosa of the guinea-pig small intestine after intracardiac injection. The substances investigated were: /sup 14/C-urea, /sup 3/H-mannose, /sup 3/H-inulin, and /sup 125/I polyvinylpyrrolidone (PVP). Small bowel biopsies were taken at intervals from one to 60 minutes after injection and the tissues processed for autoradiography. Light microscopic examination of the autoradiographs showed that the compartmental distribution depended on the molecular size of the substances being studied. Urea and mannose, as small solutes, were uniformly distributed throughout the intravascular, extravascular, and epithelial compartments. Inulin was evenly distributed in the vessel lumen and extravascular space but there was a considerable drop in concentration in the epithelium. PVP exhibited the most marked gradients, the concentration being greatest in the vascular lumina, lower in the extravascular space, least in the epithelium. Thus there appear to be two barriers to macromolecular passage which are freely permeable to small solutes: the capillary wall and the epithelium. At a light microscopical level it was not possible to observe whether the limiting membrane of each of these barriers is the cell plasmalemmal membrane or the basement membrane. The selectivity of the epithelial barrier was greater than that of the capillary barrier.

Overcoming barriers to exercise among parents: A social cognitive theory perspective

Science.gov (United States)

Mailey, Emily L.; Phillips, Siobhan M.; Dlugonski, Deirdre; Conroy, David E.

2017-01-01

Parents face numerous barriers to exercise and exhibit high levels of inactivity. Examining theory-based determinants of exercise among parents may inform interventions for this population. The purpose of this study was to test a social-cognitive model of parental exercise participation over a 12-month period. Mothers (n=226) and fathers (n=70) of children exercise, barriers self-efficacy, perceived barriers, and exercise planning at baseline and one year later. Panel analyses were used to test the hypothesized relationships. Barriers self-efficacy was related to exercise directly and indirectly through perceived barriers and prioritization/planning. Prioritization and planning also mediated the relationship between perceived barriers and exercise. These paths remained significant at 12 months. These results suggest efforts to increase exercise in parents should focus on improving confidence to overcome exercise barriers, reducing perceptions of barriers, and helping parents make specific plans for prioritizing and engaging in exercise. PMID:27108160

Influence of solid noise barriers on near-road and on-road air quality

Science.gov (United States)

Baldauf, Richard W.; Isakov, Vlad; Deshmukh, Parikshit; Venkatram, Akula; Yang, Bo; Zhang, K. Max

2016-03-01

Public health concerns regarding adverse health effects for populations spending significant amounts of time near high traffic roadways has increased substantially in recent years. Roadside features, including solid noise barriers, have been investigated as potential methods that can be implemented in a relatively short time period to reduce air pollution exposures from nearby traffic. A field study was conducted to determine the influence of noise barriers on both on-road and downwind pollutant concentrations near a large highway in Phoenix, Arizona, USA. Concentrations of nitrogen dioxide, carbon monoxide, ultrafine particles, and black carbon were measured using a mobile platform and fixed sites along two limited-access stretches of highway that contained a section of noise barrier and a section with no noise barrier at-grade with the surrounding terrain. Results of the study showed that pollutant concentrations behind the roadside barriers were significantly lower relative to those measured in the absence of barriers. The reductions ranged from 50% within 50 m from the barrier to about 30% as far as 300 m from the barrier. Reductions in pollutant concentrations generally began within the first 50 m of the barrier edge; however, concentrations were highly variable due to vehicle activity behind the barrier and along nearby urban arterial roadways. The concentrations on the highway, upwind of the barrier, varied depending on wind direction. Overall, the on-road concentrations in front of the noise barrier were similar to those measured in the absence of the barrier, contradicting previous modeling results that suggested roadside barriers increase pollutant levels on the road. Thus, this study suggests that noise barriers do reduce potential pollutant exposures for populations downwind of the road, and do not likely increase exposures to traffic-related pollutants for vehicle passengers on the highway.

Interaction enablers, drivers and barriers of collaborative innovation projects between small firms and academia

DEFF Research Database (Denmark)

Filip, Diane; Hansen, Bettina Dencker; Frølunde, Thea Thorsgaard

2016-01-01

drivers, and main barriers. Our three major findings relate to the phases of a structured program, elements of collaborative innovation projects, and the facilitation of interaction at two levels, i.e. meta-level and micro-level, by two types of brokers. The operator of the regional program facilitates...... types of brokers acting at two different levels have proven to be useful in overcoming some of the classical barriers firms face when interacting with academia. Essentially, the gap between the world of business and the world of academia has been mitigated by the structured and formalized interactions...

Hanford prototype-barrier status report: FY 1995

International Nuclear Information System (INIS)

Gee, G.W.; Ward, A.L.; Gilmore, B.G.; Ligotke, M.W.; Link, S.O.

1995-11-01

Surface barriers (or covers) have been proposed for use at the Hanford Site as a means to isolate certain waste sites that, for reasons of cost or worker safety or both, may not be exhumed. Surface barriers are intende to isolated the wastes from the accessible environment and to provide long-term protection to future populations that might use the Hanford Site. Currently, no ''proven'' long-term barrier system is available. For this reason, the Hanford Site Permanent Isolation Surface-Barrier Development Program (BDP) was organized to develop the technology needed to provide long-term surface barrier capability for the Hanford Site for the US Department of Energy (DOE). Designs have been proposed to meet the most stringent needs for long-term waste disposal. The objective of the current barrier design is to use natural materials to develop a protective barrier system that isolates wastes for at least 1000 years by limiting water, plant, animal, and human intrusion; and minimizing erosion. The design criteria for water drainage has been set at 0.5 mm/yr. While other design criteria are more qualitative, it is clear that waste isolation for an extended time is the prime objective of the design. Constructibility and performance. are issues that can be tested and dealt with by evaluating prototype designs prior to extensive construction and deployment of covers for waste sites at Hanford

Barriers to the development of the short supply chain for local food producers in Romania

Directory of Open Access Journals (Sweden)

Lavinia DOVLEAC

2017-07-01

Full Text Available This article highlights the importance of short food supply chains for the development of rural areas in Romania, considering the increasing demand of the population for healthy food. A proper functionality of these local food supply chains brings benefits to producers, consumers and the local community, but some issues must be solved. This article presents the results of a qualitative marketing research study conducted for identifying the difficulties in this sector. The study aimed to identify the small producers’ opinions on the barriers to the development of these supply chains and how they could be helped to sell their products at a fair price.

Chimerism in wild adult populations of the broadcast spawning coral Acropora millepora on the Great Barrier Reef.

Directory of Open Access Journals (Sweden)

Eneour Puill-Stephan

2009-11-01

Full Text Available Chimeras are organisms containing tissues or cells of two or more genetically distinct individuals, and are known to exist in at least nine phyla of protists, plants, and animals. Although widespread and common in marine invertebrates, the extent of chimerism in wild populations of reef corals is unknown.The extent of chimerism was explored within two populations of a common coral, Acropora millepora, on the Great Barrier Reef, Australia, by using up to 12 polymorphic DNA microsatellite loci. At least 2% and 5% of Magnetic Island and Pelorus Island populations of A. millepora, respectively, were found to be chimeras (3% overall, based on conservative estimates. A slightly less conservative estimate indicated that 5% of colonies in each population were chimeras. These values are likely to be vast underestimates of the true extent of chimerism, as our sampling protocol was restricted to a maximum of eight branches per colony, while most colonies consist of hundreds of branches. Genotypes within chimeric corals showed high relatedness, indicating that genetic similarity is a prerequisite for long-term acceptance of non-self genotypes within coral colonies.While some brooding corals have been shown to form genetic chimeras in their early life history stages under experimental conditions, this study provides the first genetic evidence of the occurrence of coral chimeras in the wild and of chimerism in a broadcast spawning species. We hypothesize that chimerism is more widespread in corals than previously thought, and suggest that this has important implications for their resilience, potentially enhancing their capacity to compete for space and respond to stressors such as pathogen infection.

Agricultural Trade Barriers 10 years later Uruguay Round Trade Agreement Signature

OpenAIRE

Mahia, R.; Arce, Rafael de; Escribano, Gonzalo

2005-01-01

In this paper, an analysis of current state of agricultural trade barriers is carried out alter ten years of Uruguay Round Agricultural Trade Agreement Signature The descriptive analysis showed that small advances in trade barriers removing have been taken out. About the heterogeneity in tariff applications, tariff progresivity and peak tariffs, the same situation is pointed out.

Phytophthora have distinct endogenous small RNA populations that include short interfering and microRNAs.

Directory of Open Access Journals (Sweden)

Noah Fahlgren

Full Text Available In eukaryotes, RNA silencing pathways utilize 20-30-nucleotide small RNAs to regulate gene expression, specify and maintain chromatin structure, and repress viruses and mobile genetic elements. RNA silencing was likely present in the common ancestor of modern eukaryotes, but most research has focused on plant and animal RNA silencing systems. Phytophthora species belong to a phylogenetically distinct group of economically important plant pathogens that cause billions of dollars in yield losses annually as well as ecologically devastating outbreaks. We analyzed the small RNA-generating components of the genomes of P. infestans, P. sojae and P. ramorum using bioinformatics, genetic, phylogenetic and high-throughput sequencing-based methods. Each species produces two distinct populations of small RNAs that are predominantly 21- or 25-nucleotides long. The 25-nucleotide small RNAs were primarily derived from loci encoding transposable elements and we propose that these small RNAs define a pathway of short-interfering RNAs that silence repetitive genetic elements. The 21-nucleotide small RNAs were primarily derived from inverted repeats, including a novel microRNA family that is conserved among the three species, and several gene families, including Crinkler effectors and type III fibronectins. The Phytophthora microRNA is predicted to target a family of amino acid/auxin permeases, and we propose that 21-nucleotide small RNAs function at the post-transcriptional level. The functional significance of microRNA-guided regulation of amino acid/auxin permeases and the association of 21-nucleotide small RNAs with Crinkler effectors remains unclear, but this work provides a framework for testing the role of small RNAs in Phytophthora biology and pathogenesis in future work.

Phytophthora have distinct endogenous small RNA populations that include short interfering and microRNAs.

Science.gov (United States)

Fahlgren, Noah; Bollmann, Stephanie R; Kasschau, Kristin D; Cuperus, Josh T; Press, Caroline M; Sullivan, Christopher M; Chapman, Elisabeth J; Hoyer, J Steen; Gilbert, Kerrigan B; Grünwald, Niklaus J; Carrington, James C

2013-01-01

In eukaryotes, RNA silencing pathways utilize 20-30-nucleotide small RNAs to regulate gene expression, specify and maintain chromatin structure, and repress viruses and mobile genetic elements. RNA silencing was likely present in the common ancestor of modern eukaryotes, but most research has focused on plant and animal RNA silencing systems. Phytophthora species belong to a phylogenetically distinct group of economically important plant pathogens that cause billions of dollars in yield losses annually as well as ecologically devastating outbreaks. We analyzed the small RNA-generating components of the genomes of P. infestans, P. sojae and P. ramorum using bioinformatics, genetic, phylogenetic and high-throughput sequencing-based methods. Each species produces two distinct populations of small RNAs that are predominantly 21- or 25-nucleotides long. The 25-nucleotide small RNAs were primarily derived from loci encoding transposable elements and we propose that these small RNAs define a pathway of short-interfering RNAs that silence repetitive genetic elements. The 21-nucleotide small RNAs were primarily derived from inverted repeats, including a novel microRNA family that is conserved among the three species, and several gene families, including Crinkler effectors and type III fibronectins. The Phytophthora microRNA is predicted to target a family of amino acid/auxin permeases, and we propose that 21-nucleotide small RNAs function at the post-transcriptional level. The functional significance of microRNA-guided regulation of amino acid/auxin permeases and the association of 21-nucleotide small RNAs with Crinkler effectors remains unclear, but this work provides a framework for testing the role of small RNAs in Phytophthora biology and pathogenesis in future work.

Phytophthora Have Distinct Endogenous Small RNA Populations That Include Short Interfering and microRNAs

Science.gov (United States)

Fahlgren, Noah; Bollmann, Stephanie R.; Kasschau, Kristin D.; Cuperus, Josh T.; Press, Caroline M.; Sullivan, Christopher M.; Chapman, Elisabeth J.; Hoyer, J. Steen; Gilbert, Kerrigan B.; Grünwald, Niklaus J.; Carrington, James C.

2013-01-01

In eukaryotes, RNA silencing pathways utilize 20-30-nucleotide small RNAs to regulate gene expression, specify and maintain chromatin structure, and repress viruses and mobile genetic elements. RNA silencing was likely present in the common ancestor of modern eukaryotes, but most research has focused on plant and animal RNA silencing systems. Phytophthora species belong to a phylogenetically distinct group of economically important plant pathogens that cause billions of dollars in yield losses annually as well as ecologically devastating outbreaks. We analyzed the small RNA-generating components of the genomes of P. infestans, P. sojae and P. ramorum using bioinformatics, genetic, phylogenetic and high-throughput sequencing-based methods. Each species produces two distinct populations of small RNAs that are predominantly 21- or 25-nucleotides long. The 25-nucleotide small RNAs were primarily derived from loci encoding transposable elements and we propose that these small RNAs define a pathway of short-interfering RNAs that silence repetitive genetic elements. The 21-nucleotide small RNAs were primarily derived from inverted repeats, including a novel microRNA family that is conserved among the three species, and several gene families, including Crinkler effectors and type III fibronectins. The Phytophthora microRNA is predicted to target a family of amino acid/auxin permeases, and we propose that 21-nucleotide small RNAs function at the post-transcriptional level. The functional significance of microRNA-guided regulation of amino acid/auxin permeases and the association of 21-nucleotide small RNAs with Crinkler effectors remains unclear, but this work provides a framework for testing the role of small RNAs in Phytophthora biology and pathogenesis in future work. PMID:24204767

Barriers to involvement in physical activities of persons with mental illness.

Science.gov (United States)

Shor, Ron; Shalev, Anat

2016-03-01

Participating in physical activities could be essential for reducing the multiple risk factors for health problems that persons with severe mental illness (SMI) may suffer. However, people with SMI are significantly less active than the general population. To develop knowledge about factors related to the perceived barriers hindering this population's participation in physical activities and the benefits this participation would have, a study was conducted in Israel with 86 people with mental illness living in community mental health facilities prior to their participation in a health promotion program. A mixed method was implemented and included: a scale designed to measure participants' perceptions of the barriers to and benefits of involvement in physical activities; instruments focusing on bio-psycho-social factors that may affect the level of barriers experienced; and personal interviews. The findings revealed high ranking for accessibility barriers hindering the participation in physical activities. Bio-psycho-social factors stemming from the participants' mental health, such as level of depression, were correlated with higher ranking of accessibility barriers. Bio-psycho-social factors reflecting positive mental health and health, such as positive appraisal of body weight, were correlated with lower ranking of accessibility barriers. Other barriers may include organizational and broader systemic barriers in the mental health facilities where the participants reside. These findings illuminate the need to consider the unique challenges that persons with mental illness may face in any attempt to advance their involvement in physical activity. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Adaptive management in the context of barriers in European freshwater ecosystems

DEFF Research Database (Denmark)

Birnie-Gauvin, Kim; Tummers, Jeroen S.; Lucas, Martyn C.

2017-01-01

Many natural habitats have been modified to accommodate for the presence of humans and their needs. Infrastructures e such as hydroelectric dams, weirs, culverts and bridges e are now a common occurrence in streams and rivers across the world. As a result, freshwater ecosystems have been altered...... extensively, affecting both biological and geomorphological components of the habitats. Many fish species rely on these freshwater ecosystems to complete their lifecycles, and the presence of barriers has been shown to reduce their ability to migrate and sustain healthy populations. In the long run, barriers...... may have severe repercussions on population densities and dynamics of aquatic animal species. There is currently an urgent need to address these issues with adequate conservation approaches. Adaptive management provides a relevant approach to managing barriers in freshwater ecosystems as it addresses...

Analysis of interactions among barriers in project risk management

Science.gov (United States)

Dandage, Rahul V.; Mantha, Shankar S.; Rane, Santosh B.; Bhoola, Vanita

2018-03-01

In the context of the scope, time, cost, and quality constraints, failure is not uncommon in project management. While small projects have 70% chances of success, large projects virtually have no chance of meeting the quadruple constraints. While there is no dearth of research on project risk management, the manifestation of barriers to project risk management is a less dwelt topic. The success of project management is oftentimes based on the understanding of barriers to effective risk management, application of appropriate risk management methodology, proactive leadership to avoid barriers, workers' attitude, adequate resources, organizational culture, and involvement of top management. This paper represents various risk categories and barriers to risk management in domestic and international projects through literature survey and feedback from project professionals. After analysing the various modelling methods used in project risk management literature, interpretive structural modelling (ISM) and MICMAC analysis have been used to analyse interactions among the barriers and prioritize them. The analysis indicates that lack of top management support, lack of formal training, and lack of addressing cultural differences are the high priority barriers, among many others.

[The blood-brain barrier in ageing persons].

Science.gov (United States)

Haaning, Nina; Damsgaard, Else Marie; Moos, Torben

2018-03-26

Brain capillary endothelial cells (BECs) form the ultra-tight blood-brain barrier (BBB). The permeability of the BBB increases with increasing age and neurovascular and neurodegenerative diseases. Major defects of the BBB can be initiated by increased permeability to plasma proteins in small arteriosclerotic arteries and release of proteins from degenerating neurons into the brain extracellular space. These proteins deposit in perivascular spaces, and subsequently negatively influence the BECs leading to decreased expression of barrier proteins. Detection of BBB defects by the use of non-invasive techniques is relevant for clinical use in settings with advanced age and severe brain disorders.

Barriers to Business Model Innovation in Swedish Agriculture

OpenAIRE

Sivertsson, Olof; Tell, Joakim

2015-01-01

Swedish agricultural companies, especially small farms, are struggling to be profitable in difficult economic times. It is a challenge for Swedish farmers to compete with imported products on prices. The agricultural industry, however, supports the view that through business model innovation, farms can increase their competitive advantage. This paper identifies and describes some of the barriers Swedish small farms encounter when they consider business model innovation. A qualitative approach...

The capital barrier to innovation in the small and medium-sized enterprises

OpenAIRE

Lewandowska, Lucyna

2009-01-01

The article discusses SMEs' situation with reference to the process of creating an innovative economy. The presented discussion covers both non-material and financial barriers impeding the development of innovations. The examined range of new solutions designed to finance innovation includes types of capital support such as leasing, franchising, venture capital, Business Angels, NewConnect.

Making a business case for small medical practices to maintain quality while addressing racial healthcare disparities.

Science.gov (United States)

Dunston, Frances J; Eisenberg, Andrew C; Lewis, Evelyn L; Montgomery, John M; Ramos, Diana; Elster, Arthur

2008-11-01

Various reports have documented variations in quality of care that occur among racial and ethnic populations, even after accounting for socioeconomic factors and health insurance status. Although quality improvement initiatives are often touted as the answer to healthcare disparities, researchers have questioned whether a business case exists that supports this notion. We assess various barriers and incentives for using quality improvement to address racial and ethnic healthcare disparities in small-to-medium-sized practices. We believe that although both indirect and direct cost incentives may exist, a favorable business case for small private practices cannot be made unless there are additional financial incentives. The business community can work with health plans to provide these incentives.

On the porosity of barrier layers

Directory of Open Access Journals (Sweden)

J. Mignot

2009-09-01

Full Text Available Barrier layers are defined as the layer between the pycnocline and the thermocline when the latter are different as a result of salinity stratification. We present a revisited 2-degree resolution global climatology of monthly mean oceanic Barrier Layer (BL thickness first proposed by de Boyer Montégut et al. (2007. In addition to using an extended data set, we present a modified computation method that addresses the observed porosity of BLs. We name porosity the fact that barrier layers distribution can, in some areas, be very uneven regarding the space and time scales that are considered. This implies an intermittent alteration of air-sea exchanges by the BL. Therefore, it may have important consequences for the climatic impact of BLs. Differences between the two computation methods are small for robust BLs that are formed by large-scale processes. However, the former approach can significantly underestimate the thickness of short and/or localized barrier layers. This is especially the case for barrier layers formed by mesoscale mechanisms (under the intertropical convergence zone for example and along western boundary currents and equatorward of the sea surface salinity subtropical maxima. Complete characterisation of regional BL dynamics therefore requires a description of the robustness of BL distribution to assess the overall impact of BLs on the process of heat exchange between the ocean interior and the atmosphere.

Integrated analysis for population estimation, management impact evaluation, and decision-making for a declining species

Science.gov (United States)

Crawford, Brian A.; Moore, Clinton; Norton, Terry M.; Maerz, John C.

2018-01-01

A challenge for making conservation decisions is predicting how wildlife populations respond to multiple, concurrent threats and potential management strategies, usually under substantial uncertainty. Integrated modeling approaches can improve estimation of demographic rates necessary for making predictions, even for rare or cryptic species with sparse data, but their use in management applications is limited. We developed integrated models for a population of diamondback terrapins (Malaclemys terrapin) impacted by road-associated threats to (i) jointly estimate demographic rates from two mark-recapture datasets, while directly estimating road mortality and the impact of management actions deployed during the study; and (ii) project the population using population viability analysis under simulated management strategies to inform decision-making. Without management, population extirpation was nearly certain due to demographic impacts of road mortality, predators, and vegetation. Installation of novel flashing signage increased survival of terrapins that crossed roads by 30%. Signage, along with small roadside barriers installed during the study, increased population persistence probability, but the population was still predicted to decline. Management strategies that included actions targeting multiple threats and demographic rates resulted in the highest persistence probability, and roadside barriers, which increased adult survival, were predicted to increase persistence more than other actions. Our results support earlier findings showing mitigation of multiple threats is likely required to increase the viability of declining populations. Our approach illustrates how integrated models may be adapted to use limited data efficiently, represent system complexity, evaluate impacts of threats and management actions, and provide decision-relevant information for conservation of at-risk populations.

Small-bowel permeability in collagenous colitis

DEFF Research Database (Denmark)

Wildt, Signe; Madsen, Jan L; Rumessen, Jüri J

2006-01-01

Collagenous colitis (CC) is a chronic inflammatory bowel disease that affects the colon. However, some patients with CC present with accompanying pathologic small-bowel manifestations such as coeliac disease, defects in bile acid absorption and histopathologic changes in small-intestinal biopsies......, indicating that CC is a pan-intestinal disease. In small-intestinal disease, the intestinal barrier function may be impaired, and the permeability of the small intestine altered. The purpose of this research was to study small-bowel function in patients with CC as expressed by intestinal permeability....

Deep inelastic scattering near the Coulomb barrier

International Nuclear Information System (INIS)

Gehring, J.; Back, B.; Chan, K.

1995-01-01

Deep inelastic scattering was recently observed in heavy ion reactions at incident energies near and below the Coulomb barrier. Traditional models of this process are based on frictional forces and are designed to predict the features of deep inelastic processes at energies above the barrier. They cannot be applied at energies below the barrier where the nuclear overlap is small and friction is negligible. The presence of deep inelastic scattering at these energies requires a different explanation. The first observation of deep inelastic scattering near the barrier was in the systems 124,112 Sn + 58,64 Ni by Wolfs et al. We previously extended these measurements to the system 136 Xe + 64 Ni and currently measured the system 124 Xe + 58 Ni. We obtained better statistics, better mass and energy resolution, and more complete angular coverage in the Xe + Ni measurements. The cross sections and angular distributions are similar in all of the Sn + Ni and Xe + Ni systems. The data are currently being analyzed and compared with new theoretical calculations. They will be part of the thesis of J. Gehring

Use of Postpartum Care: Predictors and Barriers

Directory of Open Access Journals (Sweden)

Jessica N. DiBari

2014-01-01

Full Text Available This study aimed to identify actual and perceived barriers to postpartum care among a probability sample of women who gave birth in Los Angeles County, California in 2007. Survey data from the 2007 Los Angeles Mommy and Baby (LAMB study (N = 4,075 were used to identify predictors and barriers to postpartum care use. The LAMB study was a cross-sectional, population-based study that examined maternal and child health outcomes during the preconception, prenatal, and postpartum periods. Multivariable analyses identified low income, being separated/divorced and never married, trying hard to get pregnant or trying to prevent pregnancy, Medi-Cal insurance holders, and lack of prenatal care to be risk factors of postpartum care nonuse, while Hispanic ethnicity was protective. The most commonly reported barriers to postpartum care use were feeling fine, being too busy with the baby, having other things going on, and a lack of need. Findings from this study can inform the development of interventions targeting subgroups at risk for not obtaining postpartum care. Community education and improved access to care can further increase the acceptability of postpartum visits and contribute to improvements in women’s health. Postpartum care can serve as a gateway to engage underserved populations in the continuum of women’s health care.

Small Schools, Real Gains.

Science.gov (United States)

Wasley, Patricia A.; Lear, Richard J.

2001-01-01

Small school size (fewer than 400 students) makes possible success-enhancing structures and practices: strong, ongoing student/adult and home/school relationships; flat organizational structure; concentration on a few goals; ongoing, site-specific professional development; a respectful culture; and community engagement. Implementation barriers are…

Energy efficiency barriers in commercial and industrial firms in Ukraine: An empirical analysis

International Nuclear Information System (INIS)

Hochman, Gal; Timilsina, Govinda R.

2017-01-01

Improvement in energy efficiency is one of the main options to reduce energy demand and greenhouse gas emissions. However, large-scale deployment of energy-efficient technologies is constrained by several factors. Employing a survey of 509 industrial and commercial firms throughout Ukraine and a generalized ordered logit model, we quantified the economic, behavioral, and institutional barriers that may impede the deployment of energy-efficient technologies. Our analysis shows that behavioral barriers resulted from lack of information, knowledge, and awareness are major impediments to the adoption of energy-efficient technologies in Ukraine, and that financial barriers may further impede investments in these technologies especially for small firms. This suggests that carefully targeted information provisions and energy audits will enhance Ukrainian firms' investments in energy-efficient technologies to save energy consumption, improve productivity, and reduce carbon emissions from the productive sectors. - Highlights: • Employing a survey of 509 industrial and commercial firms throughout Ukraine • A generalized ordered logit model is used in the analysis. • The paper quantifies the economic, behavioral, and institutional barriers to energy-efficient technologies. • Behavioral barriers are major impediments to the adoption of energy-efficient technologies. • Financial barriers may further impede investments in these technologies especially for small firms.

Population Density and AIDS-Related Stigma in Large-Urban, Small-Urban, and Rural Communities of the Southeastern USA.

Science.gov (United States)

Kalichman, Seth; Katner, Harold; Banas, Ellen; Kalichman, Moira

2017-07-01

AIDS stigmas delay HIV diagnosis, interfere with health care, and contribute to mental health problems among people living with HIV. While there are few studies of the geographical distribution of AIDS stigma, research suggests that AIDS stigmas are differentially experienced in rural and urban areas. We conducted computerized interviews with 696 men and women living with HIV in 113 different zip code areas that were classified as large-urban, small-urban, and rural areas in a southeast US state with high-HIV prevalence. Analyses conducted at the individual level (N = 696) accounting for clustering at the zip code level showed that internalized AIDS-related stigma (e.g., the sense of being inferior to others because of HIV) was experienced with greater magnitude in less densely populated communities. Multilevel models indicated that after adjusting for potential confounding factors, rural communities reported greater internalized AIDS-related stigma compared to large-urban areas and that small-urban areas indicated greater experiences of enacted stigma (e.g., discrimination) than large-urban areas. The associations between anticipated AIDS-related stigma (e.g., expecting discrimination) and population density at the community-level were not significant. Results suggest that people living in rural and small-urban settings experience greater AIDS-related internalized and enacted stigma than their counterparts living in large-urban centers. Research is needed to determine whether low-density population areas contribute to or are sought out by people who experienced greater AIDS-related stigma. Regardless of causal directions, interventions are needed to address AIDS-related stigma, especially among people in sparsely populated areas with limited resources.

Targeting cessation: understanding barriers and motivations to quitting among urban adult daily tobacco smokers.

Science.gov (United States)

Rosenthal, Lisa; Carroll-Scott, Amy; Earnshaw, Valerie A; Sackey, Naa; O'Malley, Stephanie S; Santilli, Alycia; Ickovics, Jeannette R

2013-03-01

Many people continue to smoke tobacco products despite known negative health consequences, including increased risk of chronic disease and death. Disparities exist in rates of smoking and chronic disease, underscoring the importance of understanding the barriers and motivations to smoking cessation among vulnerable populations, such as socioeconomically disadvantaged people of color. This study uses data from a cross-sectional randomized household survey conducted in six low-income neighborhoods in New Haven, Connecticut, USA (N=1205). The objectives were to examine barriers and motivations to quitting smoking among daily tobacco smokers (31.6% of respondents) and sociodemographic differences in endorsement of barriers and motivations. The two most common barriers to quitting were perceiving it to be too difficult and not wanting to quit. Financial costs, social support, and social influence were themes endorsed highly across both barriers and motivations to quitting. Sociodemographic differences were found, such as women and Black participants being more likely to be interested in a free quitline or quit website; women and Latinos being more likely to be afraid of gaining weight; and women, participants with less education, and older participants being more likely to be concerned about the cost of cessation products. Understanding barriers and motivations to quitting among disadvantaged populations is crucial. Financial issues, social support, and social norms should be targeted in promoting cessation among disadvantaged, urban populations. Programs, interventions, and policies can also use research about specific barriers and motivations for sociodemographic sub-groups to be tailored, targeted, and more effective. Copyright © 2012 Elsevier Ltd. All rights reserved.

Large-scale, multidirectional larval connectivity among coral reef fish populations in the Great Barrier Reef Marine Park

KAUST Repository

Williamson, David H.; Harrison, Hugo B.; Almany, Glenn R.; Berumen, Michael L.; Bode, Michael; Bonin, Mary C.; Choukroun, Severine; Doherty, Peter J.; Frisch, Ashley J.; Saenz-Agudelo, Pablo; Jones, Geoffrey P.

2016-01-01

Larval dispersal is the key process by which populations of most marine fishes and invertebrates are connected and replenished. Advances in larval tagging and genetics have enhanced our capacity to track larval dispersal, assess scales of population connectivity, and quantify larval exchange among no-take marine reserves and fished areas. Recent studies have found that reserves can be a significant source of recruits for populations up to 40 km away, but the scale and direction of larval connectivity across larger seascapes remain unknown. Here, we apply genetic parentage analysis to investigate larval dispersal patterns for two exploited coral reef groupers (Plectropomus maculatus and Plectropomus leopardus) within and among three clusters of reefs separated by 60–220 km within the Great Barrier Reef Marine Park, Australia. A total of 69 juvenile P. maculatus and 17 juvenile P. leopardus (representing 6% and 9% of the total juveniles sampled, respectively) were genetically assigned to parent individuals on reefs within the study area. We identified both short-distance larval dispersal within regions (200 m to 50 km) and long-distance, multidirectional dispersal of up to ~250 km among regions. Dispersal strength declined significantly with distance, with best-fit dispersal kernels estimating median dispersal distances of ~110 km for P. maculatus and ~190 km for P. leopardus. Larval exchange among reefs demonstrates that established reserves form a highly connected network and contribute larvae for the replenishment of fished reefs at multiple spatial scales. Our findings highlight the potential for long-distance dispersal in an important group of reef fishes, and provide further evidence that effectively protected reserves can yield recruitment and sustainability benefits for exploited fish populations.

Large-scale, multidirectional larval connectivity among coral reef fish populations in the Great Barrier Reef Marine Park

KAUST Repository

Williamson, David H.

2016-11-15

Larval dispersal is the key process by which populations of most marine fishes and invertebrates are connected and replenished. Advances in larval tagging and genetics have enhanced our capacity to track larval dispersal, assess scales of population connectivity, and quantify larval exchange among no-take marine reserves and fished areas. Recent studies have found that reserves can be a significant source of recruits for populations up to 40 km away, but the scale and direction of larval connectivity across larger seascapes remain unknown. Here, we apply genetic parentage analysis to investigate larval dispersal patterns for two exploited coral reef groupers (Plectropomus maculatus and Plectropomus leopardus) within and among three clusters of reefs separated by 60–220 km within the Great Barrier Reef Marine Park, Australia. A total of 69 juvenile P. maculatus and 17 juvenile P. leopardus (representing 6% and 9% of the total juveniles sampled, respectively) were genetically assigned to parent individuals on reefs within the study area. We identified both short-distance larval dispersal within regions (200 m to 50 km) and long-distance, multidirectional dispersal of up to ~250 km among regions. Dispersal strength declined significantly with distance, with best-fit dispersal kernels estimating median dispersal distances of ~110 km for P. maculatus and ~190 km for P. leopardus. Larval exchange among reefs demonstrates that established reserves form a highly connected network and contribute larvae for the replenishment of fished reefs at multiple spatial scales. Our findings highlight the potential for long-distance dispersal in an important group of reef fishes, and provide further evidence that effectively protected reserves can yield recruitment and sustainability benefits for exploited fish populations.

Determining barriers to creating an enabling environment in Cambodia: results from a baseline study with key populations and police.

Science.gov (United States)

Schneiders, Mira L; Weissman, Amy

2016-01-01

Cambodian law enforcement's limited acceptance of harm reduction has hindered HIV program effectiveness. With funding from the Australian Department of Foreign Affairs and Trade, FHI 360 supported the Ministry of Interior to implement the Police Community Partnership Initiative (PCPI) in Cambodia's capital Phnom Penh. To guide this, FHI 360 conducted a baseline study examining police and key populations' attitudes and practices towards one another, including fear and occurrence of arrest. Between December 2012 and January 2013, a cross-sectional survey of 199 police post officers, 199 people who use drugs (PWUD) including people who inject drugs (PWID), 199 men who have sex with men (MSM), 200 transgender women (TGW) and 200 female entertainment workers (FEW) was conducted in five Phnom Penh districts. Eligible participants were ≥18 years, members of a key population from selected hotspots or police officers, deputy chiefs or chiefs. Key populations' median age was 25 years (IQR: 22-30); 40% had completed only primary school. Police were male (99.5%), with median age 43 years (IQR: 30 to 47), and 45 and 25% high school and university completion rates, respectively. Key populations feared arrest for carrying needles and syringes (67%), condoms (23%) and 19% felt afraid to access health services. Close to 75% of police reported body searching and 58% arresting key populations in the past six months for using drugs (64%), selling or distributing drugs (36%) or being violent (13%). Self-reported arrests (23% PWUD, 6% MSM, 6% TGW, 12% FEW; ppolice believed arrest was an appropriate solution to reduce HIV and drug use and reported selling sex (88%) and carrying needles and syringes (55%) as valid reasons for arrest. Key populations' fear of accessing harm reduction and health services and police's negative attitudes and practices towards key populations present major barriers to HIV prevention efforts in Cambodia. To create an enabling environment and ensure police are

Invasive lionfish had no measurable effect on prey fish community structure across the Belizean Barrier Reef.

Science.gov (United States)

Hackerott, Serena; Valdivia, Abel; Cox, Courtney E; Silbiger, Nyssa J; Bruno, John F

2017-01-01

Invasive lionfish are assumed to significantly affect Caribbean reef fish communities. However, evidence of lionfish effects on native reef fishes is based on uncontrolled observational studies or small-scale, unrepresentative experiments, with findings ranging from no effect to large effects on prey density and richness. Moreover, whether lionfish affect populations and communities of native reef fishes at larger, management-relevant scales is unknown. The purpose of this study was to assess the effects of lionfish on coral reef prey fish communities in a natural complex reef system. We quantified lionfish and the density, richness, and composition of native prey fishes (0-10 cm total length) at sixteen reefs along ∼250 km of the Belize Barrier Reef from 2009 to 2013. Lionfish invaded our study sites during this four-year longitudinal study, thus our sampling included fish community structure before and after our sites were invaded, i.e., we employed a modified BACI design. We found no evidence that lionfish measurably affected the density, richness, or composition of prey fishes. It is possible that higher lionfish densities are necessary to detect an effect of lionfish on prey populations at this relatively large spatial scale. Alternatively, negative effects of lionfish on prey could be small, essentially undetectable, and ecologically insignificant at our study sites. Other factors that influence the dynamics of reef fish populations including reef complexity, resource availability, recruitment, predation, and fishing could swamp any effects of lionfish on prey populations.

Invasive lionfish had no measurable effect on prey fish community structure across the Belizean Barrier Reef

Directory of Open Access Journals (Sweden)

Serena Hackerott

2017-05-01

Full Text Available Invasive lionfish are assumed to significantly affect Caribbean reef fish communities. However, evidence of lionfish effects on native reef fishes is based on uncontrolled observational studies or small-scale, unrepresentative experiments, with findings ranging from no effect to large effects on prey density and richness. Moreover, whether lionfish affect populations and communities of native reef fishes at larger, management-relevant scales is unknown. The purpose of this study was to assess the effects of lionfish on coral reef prey fish communities in a natural complex reef system. We quantified lionfish and the density, richness, and composition of native prey fishes (0–10 cm total length at sixteen reefs along ∼250 km of the Belize Barrier Reef from 2009 to 2013. Lionfish invaded our study sites during this four-year longitudinal study, thus our sampling included fish community structure before and after our sites were invaded, i.e., we employed a modified BACI design. We found no evidence that lionfish measurably affected the density, richness, or composition of prey fishes. It is possible that higher lionfish densities are necessary to detect an effect of lionfish on prey populations at this relatively large spatial scale. Alternatively, negative effects of lionfish on prey could be small, essentially undetectable, and ecologically insignificant at our study sites. Other factors that influence the dynamics of reef fish populations including reef complexity, resource availability, recruitment, predation, and fishing could swamp any effects of lionfish on prey populations.

Overcoming barriers to exercise among parents: a social cognitive theory perspective.

Science.gov (United States)

Mailey, Emily L; Phillips, Siobhan M; Dlugonski, Deirdre; Conroy, David E

2016-08-01

Parents face numerous barriers to exercise and exhibit high levels of inactivity. Examining theory-based determinants of exercise among parents may inform interventions for this population. The purpose of this study was to test a social-cognitive model of parental exercise participation over a 12-month period. Mothers (n = 226) and fathers (n = 70) of children self-efficacy, perceived barriers, and exercise planning at baseline and 1 year later. Panel analyses were used to test the hypothesized relationships. Barriers self-efficacy was related to exercise directly and indirectly through perceived barriers and prioritization/planning. Prioritization and planning also mediated the relationship between perceived barriers and exercise. These paths remained significant at 12 months. These results suggest efforts to increase exercise in parents should focus on improving confidence to overcome exercise barriers, reducing perceptions of barriers, and helping parents make specific plans for prioritizing and engaging in exercise.

Erosion and foreign object damage of thermal barrier coatings

International Nuclear Information System (INIS)

Nicholls, J.R.; Jaslier, Y.; Rickerby, D.S.

1997-01-01

Thermal barrier coating technology is used in the hot sections of gas turbines to extend component life. To maximise these benefits, the thermal barrier coating has to remain intact throughout the life of the turbine. High velocity ballistic damage can lead to total thermal barrier removal, while erosion may lead to progressive loss of thickness during operation. This paper particularly addresses the erosion resistance and resistance to foreign object damage of thermal barrier coatings. It was found that EB-PVD thermal barriers are significantly more erosion resistant when impacted with alumina or silica, than the equivalent plasma spray coating, both at room temperature and 910 C. Examination of tested hardware, reveals that cracking occurs within the near surface region of the columns for EB-PVD ceramic and that erosion occurs by removal of these small blocks of material. In stark contrast, removal of material for plasma sprayed ceramic occurs through poorly bonded splat boundaries. Large particle impact results in severe damage to the EB-PVD thermal barrier, with cracks penetrating through the ceramic coating to the ceramic/bond coat interface. Material removal, per particle impact, increases with increased particle size. (orig.)

Motivators, barriers, and beliefs regarding physical activity in an older adult population.

Science.gov (United States)

Costello, Ellen; Kafchinski, Marcia; Vrazel, JoEllen; Sullivan, Patricia

2011-01-01

Regular physical activity (PA) plays an important role in improving and maintaining one's health, especially as one ages. Although many older Americans are aware of the benefits of regular PA, the majority do not participate in regular PA that meets recommended guidelines. The purpose of this study was to gain insight into the motivators, barriers, and beliefs regarding PA of independent-living older adults with easy access to fitness facilities. In this qualitative design, focus group interviews were used to explore the individual perceptions of physically active and inactive older adults regarding PA and exercise. Thirty-one older adults, over age 60 participated in focus group discussions regarding PA beliefs and behaviors. Groups were homogenous based on current PA behaviors. Demographic information was collected. Discussions were audiotaped and transcribed verbatim and deidentified. Two researchers independently coded for emergent themes. Interrater reliability was established (κ = 0.89). Peer review was used to further ensure trustworthiness and credibility. No significant differences were noted in age, body mass index, or educational levels between the physically active and inactive groups. Differences in perceptions were noted between the groups regarding the construct of PA, barriers to participation in regular PA, and the components of an ideal PA program. Physically inactive persons had much lower fitness expectations of a physically active older adult, more perceived barriers to regular PA, and required individual tailoring of a PA program if they were going to participate. In addition, inactive persons were intimidated by the fitness facilities and concerned about slowing others down in a group exercise setting. Both groups shared similar motivators to participate in PA, such as maintaining health and socialization; however, inactive persons also described PA as needing to be purposeful and fun. Physically inactive persons perceived themselves to be

"It's a small price to pay for life": faecal occult blood test (FOBT) screening for colorectal cancer, perceived barriers and facilitators.

Science.gov (United States)

Reeder, Anthony I

2011-03-25

To clarify perceptions influencing FOBT screening participation among the NZ European target population. Participants (30 female, 20 male; 50-71 years) recruited through urban (Auckland, Wellington, Christchurch) GP surgeries for in-depth, face-to-face interviews (digitally recorded and professionally transcribed verbatim). A pragmatic approach focused on aggregating transcript content. Participants believed early CRC lacked distinguishing signs and symptoms, but was treatable and suitable for screening, although slow development may undermine any sense of urgency. FOBT inaccuracies caused concern, particularly false negatives, but ongoing testing could reduce anxiety. Specimen collection was awkward, challenged social norms and individual squeamishness, but provided peace of mind, was painless, simple and private without high cost technological or professional involvement. Lacking preventive attitudes and experience of health responsibilities and screening, men were less likely to participate than women. CRC lacked public profile, highlighting government responsibility, before programme implementation, to resource high-profile education, largely through TV. General practitioner support and promotion was seen as critical. Inadequate health system capacity and resourcing was problematic. Despite challenging barriers, participants identified opportunities to increase FOBT screening participation, especially promotion to raise CRC profile, overcome perceived normative barriers and build self-efficacy. Adequate resourcing is essential to support appropriate promotion and timely programme delivery.

Consequences of actively managing a small Bull Trout population in a fragmented landscape

Science.gov (United States)

Al-Chokhachy, Robert K.; Moran, Sean; McHugh, Peter; Bernall, Shana; Fredenberg, Wade; DosSantos, Joseph M.

2015-01-01

Habitat fragmentation, which affects many native salmonid species, is one of the major factors contributing to the declines in distribution and abundance of Bull Trout Salvelinus confluentus. Increasingly, managers are considering options to maintain and enhance the persistence of isolated local populations through active management strategies. Understanding the ecological consequences of such actions is a necessary step in conservation planning. We used an individual-based model to evaluate the consequences of an ongoing management program aimed at mitigating the anthropogenic fragmentation of the lower Clark Fork River in Montana. Under this program juvenile Bull Trout are trapped and transported from small, headwater source populations to Lake Pend Oreille, Idaho, for rearing, and adults are subsequently recaptured in their upstream migration and returned to the natal population for spawning. We examined one of these populations and integrated empirical estimates of demographic parameters to simulate different management scenarios where moderate (n = 4) and high (n = 8) numbers of age-2, age-3, or age-4 Bull Trout were removed for transport with variable return rates under both demographic stochasticity and environmental perturbations. Our results indicated the risks from removal with no returns increased substantially when removal totals and age of Bull Trout removed from the simulated population increased. Specifically, removing eight age-3 or age-4 individuals resulted in 26% and 62% reductions in average adult population size, respectively, across simulations. We found the risks of transport were not likely alleviated with low (3%) or moderate (6%) return rates, and there were considerable risks of declines for the source population even when return rates were extremely high (>12%). Our simulations indicated little risk of declines for the source population with removals of age-2 Bull Trout, and any risks were alleviated with low return rates. However, we

Nanoparticle (MPG)-mediated delivery of small RNAs into human ...

African Journals Online (AJOL)

The cellular membrane constitutes an effective barrier that protects the complex, yet highly ordered, intracellular compartment of the cell. Passage of molecules across this barrier is highly regulated and highly restricted. Cell penetrating peptides (CPPs) are a class of small cationic peptides that are able to defy the rules of ...

Methodological approach for substantiating disease freedom in a heterogeneous small population. Application to ovine scrapie, a disease with a strong genetic susceptibility.

Science.gov (United States)

Martinez, Marie-José; Durand, Benoit; Calavas, Didier; Ducrot, Christian

2010-06-01

Demonstrating disease freedom is becoming important in different fields including animal disease control. Most methods consider sampling only from a homogeneous population in which each animal has the same probability of becoming infected. In this paper, we propose a new methodology to calculate the probability of detecting the disease if it is present in a heterogeneous population of small size with potentially different risk groups, differences in risk being defined using relative risks. To calculate this probability, for each possible arrangement of the infected animals in the different groups, the probability that all the animals tested are test-negative given this arrangement is multiplied by the probability that this arrangement occurs. The probability formula is developed using the assumption of a perfect test and hypergeometric sampling for finite small size populations. The methodology is applied to scrapie, a disease affecting small ruminants and characterized in sheep by a strong genetic susceptibility defining different risk groups. It illustrates that the genotypes of the tested animals influence heavily the confidence level of detecting scrapie. The results present the statistical power for substantiating disease freedom in a small heterogeneous population as a function of the design prevalence, the structure of the sample tested, the structure of the herd and the associated relative risks. (c) 2010 Elsevier B.V. All rights reserved.

Workplace Lactation Programs in Small WIC Service Sites: A Potential Model.

Science.gov (United States)

Angeletti, Michelle A; Llossas, Jose R

2018-03-01

The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) has an opportunity to protect, promote, and support breastfeeding by implementing and modeling workplace lactation programs in small WIC agencies that may have barriers regarding the lack of both human and financial resources. The goal of this article was to describe effective strategies for agency administrators in small WIC service sites so that they can reduce barriers, successfully implement workplace lactation policies and programs, and model successful strategies for other small employers. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

[Barriers for the implementation of cognitive services in Spanish community pharmacies].

Science.gov (United States)

Gastelurrutia, Miguel Angel; Fernández-Llimos, Fernando; Benrimoj, Shalom I; Castrillon, Carla Cristina; Faus, María José

2007-09-01

To identify and assess barriers for dissemination, implementation, and sustainability of different cognitive services in Spanish community pharmacies. Qualitative study through semi-structured interviews followed by a descriptive analysis. Two groups of experts related to Spanish community pharmacy were chosen. One with 15 community pharmacists with a relevant professional activity, while the other group (n=18) was related to pharmacy strategists. The lack of university clinical oriented learning, lack of pharmacists' attitude towards change and some uncertainty over their professional future were identified as barriers at the pharmacists' level. In relation to pharmacy as an organization the lack of clear messages by their leaders and the small volume of Spanish pharmacies were identified as barriers. In the category of pharmacy profession, the current reimbursement system, the lack of university clinical education, and the lack of leadership by current representative organizations were the barriers found. The lack of real involvement by health authorities, the lack of knowledge about the objectives of pharmacy cognitive services, and the lack of demand of these services by patients where also identified as barriers. Finally, 12 barriers were identified and grouped into 6 categories. These barriers fit in with the barriers identified in other countries.

Deep inelastic scattering near the Coulomb barrier

Energy Technology Data Exchange (ETDEWEB)

Gehring, J.; Back, B.; Chan, K. [and others

1995-08-01

Deep inelastic scattering was recently observed in heavy ion reactions at incident energies near and below the Coulomb barrier. Traditional models of this process are based on frictional forces and are designed to predict the features of deep inelastic processes at energies above the barrier. They cannot be applied at energies below the barrier where the nuclear overlap is small and friction is negligible. The presence of deep inelastic scattering at these energies requires a different explanation. The first observation of deep inelastic scattering near the barrier was in the systems {sup 124,112}Sn + {sup 58,64}Ni by Wolfs et al. We previously extended these measurements to the system {sup 136}Xe + {sup 64}Ni and currently measured the system {sup 124}Xe + {sup 58}Ni. We obtained better statistics, better mass and energy resolution, and more complete angular coverage in the Xe + Ni measurements. The cross sections and angular distributions are similar in all of the Sn + Ni and Xe + Ni systems. The data are currently being analyzed and compared with new theoretical calculations. They will be part of the thesis of J. Gehring.

Adaptive management in the context of barriers in European freshwater ecosystems.

Science.gov (United States)

Birnie-Gauvin, Kim; Tummers, Jeroen S; Lucas, Martyn C; Aarestrup, Kim

2017-12-15

Many natural habitats have been modified to accommodate for the presence of humans and their needs. Infrastructures - such as hydroelectric dams, weirs, culverts and bridges - are now a common occurrence in streams and rivers across the world. As a result, freshwater ecosystems have been altered extensively, affecting both biological and geomorphological components of the habitats. Many fish species rely on these freshwater ecosystems to complete their lifecycles, and the presence of barriers has been shown to reduce their ability to migrate and sustain healthy populations. In the long run, barriers may have severe repercussions on population densities and dynamics of aquatic animal species. There is currently an urgent need to address these issues with adequate conservation approaches. Adaptive management provides a relevant approach to managing barriers in freshwater ecosystems as it addresses the uncertainties of dealing with natural systems, and accommodates for future unexpected events, though this approach may not be suitable in all instances. A literature search on this subject yielded virtually no output. Hence, we propose a step-by-step guide for implementing adaptive management, which could be used to manage freshwater barriers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sprache als Barriere (Language as a Barrier)

Science.gov (United States)

Mattheier, Klaus

1974-01-01

The concept of language barrier has its derivations in the fields of dialectology, sociology and psychology. In contemporary usage however, the concept has two meanings i.e. regional-cultural barrier and socio-cultural barrier. (Text is in German.) (DS)

Understanding barriers to medication adherence in the hypertensive population by evaluating responses to a telephone survey

Directory of Open Access Journals (Sweden)

Nair KV

2011-04-01

Full Text Available Kavita V Nair1, Daniel A Belletti3, Joseph J Doyle3, Richard R Allen4, Robert B McQueen1, Joseph J Saseen1, Joseph Vande Griend1, Jay V Patel5, Angela McQueen2, Saira Jan21School of Pharmacy, University of Colorado, Aurora, CO, USA; 2Horizon Blue Cross Blue Shield of New Jersey, Newark, NJ, USA; 3Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA, 4Peakstat Statistical Services, Evergreen, CO, USA; 5Care Management International, Marlborough, MA, USABackground: Although hypertension is a major risk factor for cardiovascular disease, adherence to hypertensive medications is low. Previous research identifying factors influencing adherence has focused primarily on broad, population-based approaches. Identifying specific barriers for an individual is more useful in designing meaningful targeted interventions. Using customized telephonic outreach, we examined specific patient-reported barriers influencing hypertensive patients' nonadherence to medication in order to identify targeted interventions.Methods: A telephone survey of 8692 nonadherent hypertensive patients was conducted. The patient sample comprised health plan members with at least two prescriptions for antihypertensive medications in 2008. The telephone script was based on the "target" drug associated with greatest nonadherence (medication possession ratio [MPR] <80% during the four-month period preceding the survey.Results: The response rate was 28.2% of the total sample, representing 63.8% of commercial members and 37.2% of Medicare members. Mean age was 63.4 years. Mean MPR was 61.0% for the target drug. Only 58.2% of Medicare respondents and 60.4% of commercial respondents reported "missing a dose of medication". The primary reason given was "forgetfulness" (61.8% Medicare, 60.8% commercial, followed by "being too busy" (2.7% Medicare, 18.5% commercial and "other reasons" (21.9% Medicare, 8.1% commercial including travel, hospitalization/sickness, disruption of daily events

Empirical investigation of energy efficiency barriers in Italian manufacturing SMEs

International Nuclear Information System (INIS)

Trianni, Andrea; Cagno, Enrico; Worrell, Ernst; Pugliese, Giacomo

2013-01-01

The paper identifies and evaluates barriers to industrial energy efficiency through the investigation of 48 manufacturing Small and Medium-sized Enterprises (SMEs) in Northern Italy. The research provides interesting suggestions both for enterprises and energy policy-makers. Firstly, economic and information barriers are perceived as the major obstacles to the adoption of energy-efficient technologies, whilst behavioural barriers do not seem to affect enterprises very much. Nonetheless, despite what declared, the most relevant barriers are the lack of interest in energy efficiency and the existence of other priorities, thus showing that decision-makers tend to downgrade energy efficiency to a marginal issue. Furthermore, perceived barriers do not take place exclusively in implementing energy-efficient technologies, but, with comparable importance, also in generating the interest and knowledge of the opportunities. Moreover, the study highlights that relevant differences can be appreciated for both perceived and real barriers even among SMEs, that thus should not be bundled together. In addition to that, other factors affect barriers, stimulating future research: indeed, lower real barriers can be observed with higher complexity of the production, high variability of the demand and strong competitors. -- Highlights: ► Evidence of existing misalignments between perceived and real barriers to the adoption of energy-efficient technologies. ► Relevance of barriers to the generation of interest towards energy efficiency. ► Evidence of firm's size (within SMEs) and energy expenditures on barriers to energy efficiency. ► Importance, for energy efficiency barriers, of avoid bundling SMEs as a whole. ► Preliminary evidence of factors related to supply chain complexity affecting barriers to energy efficiency.

Barriers to cancer screening among Orthodox Jewish women.

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Tkatch, Rifky; Hudson, Janella; Katz, Anne; Berry-Bobovski, Lisa; Vichich, Jennifer; Eggly, Susan; Penner, Louis A; Albrecht, Terrance L

2014-12-01

The increased risk of genetic cancer mutations for Ashkenazi Jews is well known. However, little is known about the cancer-related health behaviors of a subset of Ashkenazi Jews, Orthodox Jews, who are a very religious and insular group. This study partnered with Rabbinical leadership and community members in an Orthodox Jewish community to investigate barriers to cancer screening in this community. Orthodox Jewish women were recruited to participate in focus groups designed to elicit their perspectives on barriers to cancer screening. A total of five focus groups were conducted, consisting of 3-5 members per group, stratified by age and family history of cancer. Focus groups were audio recorded and transcribed. Transcripts were coded using conventional content analysis. The resulting themes identified as barriers to cancer screening were: preservation of hidden miracles, fate, cost, competing priorities, lack of culturally relevant programming, lack of information, and fear. These results provide a unique perspective on barriers to cancer screening in a high risk but understudied population. Findings from this study may serve to inform culturally appropriate cancer education programs to overcome barriers to screening in this and other similar communities.

Strategies to improve drug delivery across the blood-brain barrier.

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de Boer, Albertus G; Gaillard, Pieter J

2007-01-01

The blood-brain barrier (BBB), together with the blood-cerebrospinal-fluid barrier, protects and regulates the homeostasis of the brain. However, these barriers also limit the transport of small-molecule and, particularly, biopharmaceutical drugs such as proteins, genes and interference RNA to the brain, thereby limiting the treatment of many brain diseases. As a result, various drug delivery and targeting strategies are currently being developed to enhance the transport and distribution of drugs into the brain. In this review, we discuss briefly the biology and physiology of the BBB as the most important barrier for drug transport to the brain and, in more detail, the possibilities for delivering large-molecule drugs, particularly genes, by receptor-mediated nonviral drug delivery to the (human) brain. In addition, the systemic and intracellular pharmacokinetics of nonviral gene delivery, together with targeted brain imaging, are reviewed briefly.

Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival.

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Tinkum, Kelsey L; Stemler, Kristina M; White, Lynn S; Loza, Andrew J; Jeter-Jones, Sabrina; Michalski, Basia M; Kuzmicki, Catherine; Pless, Robert; Stappenbeck, Thaddeus S; Piwnica-Worms, David; Piwnica-Worms, Helen

2015-12-22

Short-term fasting protects mice from lethal doses of chemotherapy through undetermined mechanisms. Herein, we demonstrate that fasting preserves small intestinal (SI) architecture by maintaining SI stem cell viability and SI barrier function following exposure to high-dose etoposide. Nearly all SI stem cells were lost in fed mice, whereas fasting promoted sufficient SI stem cell survival to preserve SI integrity after etoposide treatment. Lineage tracing demonstrated that multiple SI stem cell populations, marked by Lgr5, Bmi1, or HopX expression, contributed to fasting-induced survival. DNA repair and DNA damage response genes were elevated in SI stem/progenitor cells of fasted etoposide-treated mice, which importantly correlated with faster resolution of DNA double-strand breaks and less apoptosis. Thus, fasting preserved SI stem cell viability as well as SI architecture and barrier function suggesting that fasting may reduce host toxicity in patients undergoing dose intensive chemotherapy.

Mercury exposure in a high fish eating Bolivian Amazonian population with intense small-scale gold-mining activities.

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Barbieri, Flavia Laura; Cournil, Amandine; Gardon, Jacques

2009-08-01

Methylmercury exposure in Amazonian communities through fish consumption has been widely documented in Brazil. There is still a lack of data in other Amazonian countries, which is why we conducted this study in the Bolivian Amazon basin. Simple random sampling was used from a small village located in the lower Beni River, where there is intense gold mining and high fish consumption. All participants were interviewed and hair samples were taken to measure total mercury concentrations. The hair mercury geometric mean in the general population was 3.02 microg/g (CI: 2.69-3.37; range: 0.42-15.65). Age and gender were not directly associated with mercury levels. Fish consumption showed a positive relation and so did occupation, especially small-scale gold mining. Hair mercury levels were lower than those found in Brazilian studies, but still higher than in non-exposed populations. It is necessary to assess mercury exposure in the Amazonian regions where data is still lacking, using a standardized indicator.

The population genomics of begomoviruses: global scale population structure and gene flow

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Prasanna HC

2010-09-01

Full Text Available Abstract Background The rapidly growing availability of diverse full genome sequences from across the world is increasing the feasibility of studying the large-scale population processes that underly observable pattern of virus diversity. In particular, characterizing the genetic structure of virus populations could potentially reveal much about how factors such as geographical distributions, host ranges and gene flow between populations combine to produce the discontinuous patterns of genetic diversity that we perceive as distinct virus species. Among the richest and most diverse full genome datasets that are available is that for the dicotyledonous plant infecting genus, Begomovirus, in the Family Geminiviridae. The begomoviruses all share the same whitefly vector, are highly recombinogenic and are distributed throughout tropical and subtropical regions where they seriously threaten the food security of the world's poorest people. Results We focus here on using a model-based population genetic approach to identify the genetically distinct sub-populations within the global begomovirus meta-population. We demonstrate the existence of at least seven major sub-populations that can further be sub-divided into as many as thirty four significantly differentiated and genetically cohesive minor sub-populations. Using the population structure framework revealed in the present study, we further explored the extent of gene flow and recombination between genetic populations. Conclusions Although geographical barriers are apparently the most significant underlying cause of the seven major population sub-divisions, within the framework of these sub-divisions, we explore patterns of gene flow to reveal that both host range differences and genetic barriers to recombination have probably been major contributors to the minor population sub-divisions that we have identified. We believe that the global Begomovirus population structure revealed here could

Effect of a Semi-Purified Oligosaccharide-Enriched Fraction from Caprine Milk on Barrier Integrity and Mucin Production of Co-Culture Models of the Small and Large Intestinal Epithelium

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Alicia M. Barnett

2016-05-01

Full Text Available Caprine milk contains the highest amount of oligosaccharides among domestic animals, which are structurally similar to human milk oligosaccharides (HMOs. This suggests caprine milk oligosaccharides may offer similar protective and developmental effects to that of HMOs. However, to date, studies using oligosaccharides from caprine milk have been limited. Thus, this study aimed to examine the impact of a caprine milk oligosaccharide-enriched fraction (CMOF on barrier function of epithelial cell co-cultures of absorptive enterocytes (Caco-2 cells and mucus-secreting goblet cells (HT29-MTX cells, that more closely simulate the cell proportions found in the small (90:10 and large intestine (75:25. Treatment of epithelial co-cultures with 0.4, 1.0, 2.0 and 4.0 mg/mL of CMOF was shown to have no effect on metabolic activity but did enhance cell epithelial barrier integrity as measured by trans-epithelial electrical resistance (TEER, in a dose-dependent manner. The CMOF at the maximum concentration tested (4.0 mg/mL enhanced TEER, mucin gene expression and mucin protein abundance of epithelial co-cultures, all of which are essential components of intestinal barrier function.

Effect of a Semi-Purified Oligosaccharide-Enriched Fraction from Caprine Milk on Barrier Integrity and Mucin Production of Co-Culture Models of the Small and Large Intestinal Epithelium.

Science.gov (United States)

Barnett, Alicia M; Roy, Nicole C; McNabb, Warren C; Cookson, Adrian L

2016-05-06

Caprine milk contains the highest amount of oligosaccharides among domestic animals, which are structurally similar to human milk oligosaccharides (HMOs). This suggests caprine milk oligosaccharides may offer similar protective and developmental effects to that of HMOs. However, to date, studies using oligosaccharides from caprine milk have been limited. Thus, this study aimed to examine the impact of a caprine milk oligosaccharide-enriched fraction (CMOF) on barrier function of epithelial cell co-cultures of absorptive enterocytes (Caco-2 cells) and mucus-secreting goblet cells (HT29-MTX cells), that more closely simulate the cell proportions found in the small (90:10) and large intestine (75:25). Treatment of epithelial co-cultures with 0.4, 1.0, 2.0 and 4.0 mg/mL of CMOF was shown to have no effect on metabolic activity but did enhance cell epithelial barrier integrity as measured by trans-epithelial electrical resistance (TEER), in a dose-dependent manner. The CMOF at the maximum concentration tested (4.0 mg/mL) enhanced TEER, mucin gene expression and mucin protein abundance of epithelial co-cultures, all of which are essential components of intestinal barrier function.

Barriers to Seeking Mental Health Services among Adolescents in Military Families

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Becker, Sara J.; Swenson, Rebecca; Esposito-Smythers, Christianne; Cataldo, Andrea; Spirito, Anthony

2014-01-01

Military families with adolescents experience high levels of stress associated with parental deployment, but many of these families do not seek or utilize mental health services. The current qualitative study was designed to better understand barriers to mental health treatment experienced by adolescents in military families. Focus groups and individual interviews were conducted with military adolescents (n = 13), military (non-enlisted) parents (n = 12), and mental health service providers who treat adolescents in military families (n = 20). Discussions primarily explored barriers to seeking treatment, with supplemental questions assessing the ideal elements of mental health services for this population. Seven barriers to engaging in mental health services were identified: four internal (confidentiality concerns, stigma, ethic of self-reliance, lack of perceived relevance) and three external (time and effort concerns, logistical concerns, financial concerns). Challenges engaging military adolescents in mental health services are discussed and several recommendations are offered for service providers attempting to work with this population. PMID:25574070

Barriers to Mammography Screening: How to Overcome Them

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Yasmin Hassoun

2015-10-01

Full Text Available Background: Screening mammography is an established intervention that leads to early breast cancer detection and reduced mortality. The Lebanese Ministry of Health has initiated yearly awareness campaigns and provided free mammography in multiple centers around the country. Methods: The study took place in two major areas of Lebanon - Beirut and South Lebanon. This cross-sectional survey aimed to assess knowledge about breast cancer screening and screening behaviors in the Lebanese population. The primary outcome of the study was to assess the reasons that prevented women from performing screening mammography based on our categories of questions: lack of knowledge about breast cancer, lack of access to screening facilities, failure of primary care physician to encourage screening behavior, and other reasons. Results: The major barriers to seek screening that had statistically significant P-values, in order of prevalence, included: lack of knowledge about breast cancer, followed by social reasons and lack of access. Conclusion: Given the prevalence of breast cancer in our population, it is important to understand the pitfalls that we experience in promoting awareness. Our study is the first study to reach out to the community to assess perceived barriers against screening and provide solutions for such barriers.

Modelling water vapour permeability through atomic layer deposition coated photovoltaic barrier defects

Energy Technology Data Exchange (ETDEWEB)

Elrawemi, Mohamed, E-mail: Mohamed.elrawemi@hud.ac.uk [EPSRC Centre for Innovative Manufacturing in Advanced Metrology, School of Computing and Engineering, University of Huddersfield, Huddersfield (United Kingdom); Blunt, Liam; Fleming, Leigh [EPSRC Centre for Innovative Manufacturing in Advanced Metrology, School of Computing and Engineering, University of Huddersfield, Huddersfield (United Kingdom); Bird, David, E-mail: David.Bird@uk-cpi.com [Centre for Process Innovation Limited, Sedgefield, County Durham (United Kingdom); Robbins, David [Centre for Process Innovation Limited, Sedgefield, County Durham (United Kingdom); Sweeney, Francis [EPSRC Centre for Innovative Manufacturing in Advanced Metrology, School of Computing and Engineering, University of Huddersfield, Huddersfield (United Kingdom)

2014-11-03

Transparent barrier films such as Al{sub 2}O{sub 3} used for prevention of oxygen and/or water vapour permeation are the subject of increasing research interest when used for the encapsulation of flexible photovoltaic modules. However, the existence of micro-scale defects in the barrier surface topography has been shown to have the potential to facilitate water vapour ingress, thereby reducing cell efficiency and causing internal electrical shorts. Previous work has shown that small defects (≤ 3 μm lateral dimension) were less significant in determining water vapour ingress. In contrast, larger defects (≥ 3 μm lateral dimension) seem to be more detrimental to the barrier functionality. Experimental results based on surface topography segmentation analysis and a model presented in this paper will be used to test the hypothesis that the major contributing defects to water vapour transmission rate are small numbers of large defects. The model highlighted in this study has the potential to be used for gaining a better understanding of photovoltaic module efficiency and performance. - Highlights: • A model of water vapour permeation through barrier defects is presented. • The effect of the defects on the water vapour permeability is investigated. • Defect density correlates with water vapour permeability. • Large defects may dominate the permeation properties of the barrier film.

Disability Management in Small Firms.

Science.gov (United States)

Drury, David

1991-01-01

Notes that American research has paid relatively little attention to prospects for adapting disability management practices to financial and management environment of smaller employers. Compares large and small firms in terms of employer disability practices and characteristics of disabled workers; discusses barriers to rehabilitation and…

Barriers to renewable energy penetration. A framework for analysis

DEFF Research Database (Denmark)

Painuly, Jyoti P.

2001-01-01

Renewable energy has the potential to play an important role in providing energy with sustainability to the vast populations in developing countries who as yet have no access to clean energy. Although economically viable fur several applications, renewable energy has not been able to realise its...... potential due to several barriers to its penetration. A framework has been developed in this paper to identify the barriers to renewable energy penetration acid to suggest measures to overcome them. (C) 2001 Elsevier Science Ltd. All rights reserved....

Barrier mechanisms in the Drosophila blood-brain barrier

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Samantha Jane Hindle

2014-12-01

Full Text Available The invertebrate blood-brain barrier field is growing at a rapid pace and, in recent years, studies have shown a physiologic and molecular complexity that has begun to rival its vertebrate counterpart. Novel mechanisms of paracellular barrier maintenance through GPCR signaling were the first demonstrations of the complex adaptive mechanisms of barrier physiology. Building upon this work, the integrity of the invertebrate blood-brain barrier has recently been shown to require coordinated function of all layers of the compound barrier structure, analogous to signaling between the layers of the vertebrate neurovascular unit. These findings strengthen the notion that many blood-brain barrier mechanisms are conserved between vertebrates and invertebrates, and suggest that novel findings in invertebrate model organisms will have a significant impact on the understanding of vertebrate BBB functions. In this vein, important roles in coordinating localized and systemic signaling to dictate organism development and growth are beginning to show how the blood-brain barrier can govern whole animal physiologies. This includes novel functions of blood-brain barrier gap junctions in orchestrating synchronized neuroblast proliferation, and of blood-brain barrier secreted antagonists of insulin receptor signaling. These advancements and others are pushing the field forward in exciting new directions. In this review, we provide a synopsis of invertebrate blood-brain barrier anatomy and physiology, with a focus on insights from the past 5 years, and highlight important areas for future study.

How immunocontraception can contribute to elephant management in small, enclosed reserves: Munyawana population as a case study.

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Druce, Heleen C; Mackey, Robin L; Slotow, Rob

2011-01-01

Immunocontraception has been widely used as a management tool to reduce population growth in captive as well as wild populations of various fauna. We model the use of an individual-based rotational immunocontraception plan on a wild elephant, Loxodonta africana, population and quantify the social and reproductive advantages of this method of implementation using adaptive management. The use of immunocontraception on an individual, rotational basis stretches the inter-calving interval for each individual female elephant to a management-determined interval, preventing exposing females to unlimited long-term immunocontraception use (which may have as yet undocumented negative effects). Such rotational immunocontraception can effectively lower population growth rates, age the population, and alter the age structure. Furthermore, such structured intervention can simulate natural process such as predation or episodic catastrophic events (e.g., drought), which regulates calf recruitment within an abnormally structured population. A rotational immunocontraception plan is a feasible and useful elephant population management tool, especially in a small, enclosed conservation area. Such approaches should be considered for other long-lived, social species in enclosed areas where the long-term consequences of consistent contraception may be unknown.

How immunocontraception can contribute to elephant management in small, enclosed reserves: Munyawana population as a case study.

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Heleen C Druce

Full Text Available Immunocontraception has been widely used as a management tool to reduce population growth in captive as well as wild populations of various fauna. We model the use of an individual-based rotational immunocontraception plan on a wild elephant, Loxodonta africana, population and quantify the social and reproductive advantages of this method of implementation using adaptive management. The use of immunocontraception on an individual, rotational basis stretches the inter-calving interval for each individual female elephant to a management-determined interval, preventing exposing females to unlimited long-term immunocontraception use (which may have as yet undocumented negative effects. Such rotational immunocontraception can effectively lower population growth rates, age the population, and alter the age structure. Furthermore, such structured intervention can simulate natural process such as predation or episodic catastrophic events (e.g., drought, which regulates calf recruitment within an abnormally structured population. A rotational immunocontraception plan is a feasible and useful elephant population management tool, especially in a small, enclosed conservation area. Such approaches should be considered for other long-lived, social species in enclosed areas where the long-term consequences of consistent contraception may be unknown.

Linguistic barriers at a Malawian referral hospital | Kamwendo ...

African Journals Online (AJOL)

The paper discusses a small segment of the findings of a sociolinguistic study that was conducted at a Republic of China-funded referral hospital located in the predominantly Chitumbuka-speaking Northern Malawi. The main objective of the study was to identify linguistic barriers to communication that existed at the hospital ...

Tunnel barrier and noncollinear magnetization effects on shot noise in ferromagnetic/semiconductor/ferromagnetic heterojunctions

International Nuclear Information System (INIS)

An Xingtao; Liu Jianjun

2008-01-01

Based on the scattering approach, we investigate transport properties of electrons in a one-dimensional waveguide that contains a ferromagnetic/semiconductor/ferromagnetic heterojunction and tunnel barriers in the presence of Rashba and Dresselhaus spin-orbit interactions. We simultaneously consider significant quantum size effects, quantum coherence, Rashba and Dresselhaus spin-orbit interactions and noncollinear magnetizations. It is found that the tunnel barrier plays a decisive role in the transmission coefficient and shot noise of the ballistic spin electron transport through the heterojunction. When the small tunnel barriers are considered, the transport properties of electrons are quite different from those without tunnel barriers

Angiotensin-Converting Enzyme Gene Insertion/Deletion Polymorphism and Small Vessel Cerebral Stroke in Indian Population

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Puttachandra Prabhakar

2014-01-01

Full Text Available Background. Hypertension is an established risk factor for small-vessel cerebral stroke and the renin-angiotensin system plays an important role in the maintenance of blood pressure. We aimed at evaluating the contribution of the angiotensin-converting enzyme (ACE gene insertion/deletion (I/D polymorphism to the risk of small-vessel stroke in south Indian population. Materials and Methods. We investigated 128 patients diagnosed with small-vessel stroke and 236 age, and gender-matched healthy controls. ACE I/D polymorphism was detected by polymerase chain reaction. Results. Hypertension was significantly more prevalent in the patient group and was associated with 6-fold increase in risk for stroke. ACE genotypes were in Hardy-Weinberg equilibrium in both patients and controls. Prevalence of DD, ID, and II genotypes in cases (34.4%, 43.7%, and 28% did not differ significantly from controls (31.8%, 43.2%, and 25%. The polymorphism was not associated with small-vessel stroke (OR: 1.34; 95% CI: 0.52–1.55. However, diastolic blood pressure was associated with the ACE I/D genotypes in the patients. (DD; 90.2±14.2> ID; 86.2±11.9> II; 82.3±7.8 mm Hg,  P=0.047. Conclusion. Our study showed that hypertension, but not ACE I/D polymorphism, increased the risk of small-vessel stroke.

A qualitative study on healthcare professionals’ perceived barriers to insulin initiation in a multi-ethnic population

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Lee Yew

2012-07-01

Full Text Available Abstract Background Nationwide surveys have shown that the prevalence of diabetes rates in Malaysia have almost doubled in the past ten years; yet diabetes control remains poor and insulin therapy is underutilized. This study aimed to explore healthcare professionals’ views on barriers to starting insulin therapy in people with type 2 diabetes. Methods Healthcare professionals consisting of general practitioners (n = 11, family medicine specialists (n = 10, medical officers (n = 8, government policy makers (n = 4, diabetes educators (n = 3 and endocrinologists (n = 2 were interviewed. A semi-structured topic guide was used to guide the interviews by trained facilitators. The interviews were transcribed verbatim and analysed using a thematic analysis approach. Results Insulin initiation was found to be affected by patient, healthcare professional and system factors. Patients’ barriers include culture-specific barriers such as the religious purity of insulin, preferred use of complementary medication and perceived lethality of insulin therapy. Healthcare professionals’ barriers include negative attitudes towards insulin therapy and the ‘legacy effect’ of old insulin guidelines; whilst system barriers highlight the lack of resources, language and communication challenges. Conclusions Tackling the issue of insulin initiation should not only happen during clinical consultations. It requires health education to emphasise the progressive nature of diabetes and the eventuality of insulin therapy at early stage of the illness. Healthcare professionals should be trained how to initiate insulin and communicate effectively with patients from various cultural and religious backgrounds.

Impact of diffusion barriers to small cytotoxic molecules on the efficacy of immunotherapy in breast cancer.

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Hiranmoy Das

Full Text Available Molecular-focused cancer therapies, e.g., molecularly targeted therapy and immunotherapy, so far demonstrate only limited efficacy in cancer patients. We hypothesize that underestimating the role of biophysical factors that impact the delivery of drugs or cytotoxic cells to the target sites (for associated preferential cytotoxicity or cell signaling modulation may be responsible for the poor clinical outcome. Therefore, instead of focusing exclusively on the investigation of molecular mechanisms in cancer cells, convection-diffusion of cytotoxic molecules and migration of cancer-killing cells within tumor tissue should be taken into account to improve therapeutic effectiveness. To test this hypothesis, we have developed a mathematical model of the interstitial diffusion and uptake of small cytotoxic molecules secreted by T-cells, which is capable of predicting breast cancer growth inhibition as measured both in vitro and in vivo. Our analysis shows that diffusion barriers of cytotoxic molecules conspire with γδ T-cell scarcity in tissue to limit the inhibitory effects of γδ T-cells on cancer cells. This may increase the necessary ratios of γδ T-cells to cancer cells within tissue to unrealistic values for having an intended therapeutic effect, and decrease the effectiveness of the immunotherapeutic treatment.

Inbreeding and building up small populations of stingless bees (Hymenoptera, Apidae

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Paulo Nogueira-Neto

2002-12-01

Full Text Available A study of the viability of small populations of Hymenoptera is a matter of importance to gain a better zoological, ethological, genetical and ecological knowledge of these insects, and for conservation purposes, mainly because of the consequences to the survival of colonies of many species of bees, wasps, and ants. Based on the Whiting (1943 principle, Kerr & Vencovski (1982 presented a hypothesis that states that viable populations of stingless bees (Meliponini should have at least 40 colonies to survive. This number was later extended to 44 colonies by Kerr (1985. This would be necessary to avoid any substantial amount of homozygosis in the pair of chromosomic sexual loci, by keeping at least six different sexual gene alleles in a reproductive population. In most cases this would prevent the production of useless diploid males. However, several facts weigh against considering this as a general rule. From 1990 to 2001, 287 colony divisions were made, starting with 28 foundation colonies, in the inbreeding and population experiments with the Meliponini reported here. These experiments constitute the most extensive and longest scientific research ever made with Meliponini bees. In ten different experiments presented here, seven species (one with two subspecies of Meliponini bees were inbred in five localities inside their wide-reaching native habitats, and in two localities far away from these habitats. This was done for several years. On the whole, the number of colonies increased and the loss of colonies over the years was small. In two of these experiments, although these populations were far (1,000 km and 1,200 km from their native habitat, their foundation colonies were multiplied successfuly. It was possible to build up seven strong and three expanding medium populations, starting with one, two, three or even five colonies. However, in six other cases examined here, the Whiting (1943 principle and the hypothesis of Kerr & Vencovski (1982

Barriers to global health development: An international quantitative survey.

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Bahr Weiss

Full Text Available Global health's goal of reducing low-and-middle-income country versus high-income country health disparities faces complex challenges. Although there have been discussions of barriers, there has not been a broad-based, quantitative survey of such barriers.432 global health professionals were invited via email to participate in an online survey, with 268 (62% participating. The survey assessed participants' (A demographic and global health background, (B perceptions regarding 66 barriers' seriousness, (C detailed ratings of barriers designated most serious, (D potential solutions.Thirty-four (of 66 barriers were seen as moderately or more serious, highlighting the widespread, significant challenges global health development faces. Perceived barrier seriousness differed significantly across domains: Resource Limitations mean = 2.47 (0-4 Likert scale, Priority Selection mean = 2.20, Corruption, Lack of Competence mean = 1.87, Social and Cultural Barriers mean = 1.68. Some system-level predictors showed significant but relatively limited relations. For instance, for Global Health Domain, HIV and Mental Health had higher levels of perceived Social and Cultural Barriers than other GH Domains. Individual-level global health experience predictors had small but significant effects, with seriousness of (a Corruption, Lack of Competence, and (b Priority Selection barriers positively correlated with respondents' level of LMIC-oriented (e.g., weeks/year spent in LMIC but Academic Global Health Achievement (e.g., number of global health publications negatively correlated with overall barrier seriousness.That comparatively few system-level predictors (e.g., Organization Type were significant suggests these barriers may be relatively fundamental at the system-level. Individual-level and system-level effects do have policy implications; e.g., Priority Selection barriers were among the most serious, yet effects on seriousness of how LMIC-oriented a professional

Improving access to yoga: barriers to and motivators for practice among health professions students.

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Brems, Christiane; Justice, Lauren; Sulenes, Kari; Girasa, Lisa; Ray, Julia; Davis, Madison; Freitas, Jillian; Shean, Margaret; Colgan, Dharmakaya

2015-01-01

Yoga is gaining momentum as a popular and evidence-based, integrative health care and self-care practice. The characteristics of yoga practitioners are not proportional to the demographics of the general population, especially with respect to gender and ethnicity. Several access barriers have been implicated (eg, time, cost, and access to teachers). No studies have explored the barriers to practice among health professions students. Their participation in yoga is deemed important because they are future health professionals who will make referrals to other services. Research has shown that providers who practice yoga refer more patients to yoga. To increase yoga practice among health professions students, an understanding must be developed of factors that interfere with or facilitate a regular yoga practice. The current study intended to identify such barriers and motivators. This study was a small population survey. The setting was a private university in the northwestern United States, including students in 3 of its colleges and 10 professional programs. All students (N = 1585) in the programs of the 10 health professions received e-mail requests for participation. The Acceptability of Yoga Survey was developed for purposes of a larger yoga perceptions study and implemented with health professions students. Participants were solicited via e-mail; the survey was administered online. The current study used data from that survey. Of the 498 usable, completed surveys (ie, a response rate of approximately 30%), 478 were relevant to the current study. The sample's demographics--78% women and 79% white--did not differ significantly from the population's demographics. The findings revealed the existence of common barriers that were related to (1) time; (2) cost; (3) lack of pragmatic information about access to yoga classes and teachers; and (4) stereotypes related to flexibility, athleticism, and typical yoga practitioners. Motivators included athleticism, health

Spatial genetic analyses reveal cryptic population structure and migration patterns in a continuously harvested grey wolf (Canis lupus population in north-eastern Europe.

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Maris Hindrikson

Full Text Available Spatial genetics is a relatively new field in wildlife and conservation biology that is becoming an essential tool for unravelling the complexities of animal population processes, and for designing effective strategies for conservation and management. Conceptual and methodological developments in this field are therefore critical. Here we present two novel methodological approaches that further the analytical possibilities of STRUCTURE and DResD. Using these approaches we analyse structure and migrations in a grey wolf (Canislupus population in north-eastern Europe. We genotyped 16 microsatellite loci in 166 individuals sampled from the wolf population in Estonia and Latvia that has been under strong and continuous hunting pressure for decades. Our analysis demonstrated that this relatively small wolf population is represented by four genetic groups. We also used a novel methodological approach that uses linear interpolation to statistically test the spatial separation of genetic groups. The new method, which is capable of using program STRUCTURE output, can be applied widely in population genetics to reveal both core areas and areas of low significance for genetic groups. We also used a recently developed spatially explicit individual-based method DResD, and applied it for the first time to microsatellite data, revealing a migration corridor and barriers, and several contact zones.

Artificial nests as an alternative to studies of arboreal small mammal populations: a five-year study in the Atlantic Forest, Brazil

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Diogo Loretto

2011-06-01

Full Text Available Despite the great diversity of Brazilian Atlantic forest small mammals, natural history of most species is unknown due to their cryptic and nocturnal habits, but also due to the inadequacy of methods to capture some species, especially those of arboreal habits. A new technique, based on the use of artificial nests (AN to record arboreal marsupials, is presented. Artificial nests were combined with traditional live traps to study the population ecology of four didelphid marsupial species. After 62 months of monitoring, 119 individuals were recorded 243 times (total success = 5.2%. Only 26 individuals (22% were recorded by both AN and live trap methods, and two of the four species were never captured by live traps, only by AN. Live traps alone would have provided biased data of the structure of small mammal assemblages, creating artificial tendencies in population dynamics of many species. Detectability estimates based on mark-recapture data could correct bias resulting from the use only live traps, but these estimates require that at least some individuals of each age class or stage are captured. Only the combination of AN and live traps can produce more accurate data on population dynamics and assemblage structure. This study demonstrates that artificial nests represent a new method that should be combined with live traps in studies of small mammal assemblages and populations.

Solving k-Barrier Coverage Problem Using Modified Gravitational Search Algorithm

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Yanhua Zhang

2017-01-01

Full Text Available Coverage problem is a critical issue in wireless sensor networks for security applications. The k-barrier coverage is an effective measure to ensure robustness. In this paper, we formulate the k-barrier coverage problem as a constrained optimization problem and introduce the energy constraint of sensor node to prolong the lifetime of the k-barrier coverage. A novel hybrid particle swarm optimization and gravitational search algorithm (PGSA is proposed to solve this problem. The proposed PGSA adopts a k-barrier coverage generation strategy based on probability and integrates the exploitation ability in particle swarm optimization to update the velocity and enhance the global search capability and introduce the boundary mutation strategy of an agent to increase the population diversity and search accuracy. Extensive simulations are conducted to demonstrate the effectiveness of our proposed algorithm.

Application of assisted reproduction for population management in felids: the potential and reality for conservation of small cats.

Science.gov (United States)

Swanson, William F

2006-07-01

Assisted reproductive technology (ART), using the primary applied tools of AI, ET, and sperm and embryo cryopreservation, has been promoted over the past decades for its potential to conserve endangered wildlife, including felids. However, if the goal is efficient, consistent production of viable offspring for population management, then the 'potential' of ART has yet to become 'reality' for any non-domestic cat species. For the five small-sized felids (i.e., Brazilian ocelot, fishing cat, Pallas' cat, Arabian sand cat, black-footed cat) managed by Species Survival Plans (SSPs) in North American zoos, achieving this potential may be an absolute necessity if genetically viable captive populations are to be maintained into the next century. Modeling programs suggest that current SSP populations are not sustainable without periodic introduction of new founders and improved demographic parameters, including longer generation intervals and larger population sizes. ART provides the means to address each of these management challenges. In each small cat SSP species, fecal hormone metabolite assays and seminal analysis have proven useful for characterizing basal reproductive parameters, a necessary prerequisite to developing ART. Of the five SSP species, ART has been used to produce living offspring only in the ocelot, including after AI with frozen-thawed spermatozoa and following transfer of frozen-thawed IVF embryos. The true efficacy of these techniques, however, is still unknown. To improve the applicability of ART for population management, priorities for immediate research include further investigation of ovarian stimulation protocols, sperm and embryo cryopreservation methods, embryo culture systems, and fetal and neonatal viability following ART.

Application of Texture Analysis to Study Small Vessel Disease and Blood–Brain Barrier Integrity

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Maria del C. Valdés Hernández

2017-07-01

Full Text Available ObjectivesWe evaluate the alternative use of texture analysis for evaluating the role of blood–brain barrier (BBB in small vessel disease (SVD.MethodsWe used brain magnetic resonance imaging from 204 stroke patients, acquired before and 20 min after intravenous gadolinium administration. We segmented tissues, white matter hyperintensities (WMH and applied validated visual scores. We measured textural features in all tissues pre- and post-contrast and used ANCOVA to evaluate the effect of SVD indicators on the pre-/post-contrast change, Kruskal–Wallis for significance between patient groups and linear mixed models for pre-/post-contrast variations in cerebrospinal fluid (CSF with Fazekas scores.ResultsTextural “homogeneity” increase in normal tissues with higher presence of SVD indicators was consistently more overt than in abnormal tissues. Textural “homogeneity” increased with age, basal ganglia perivascular spaces scores (p < 0.01 and SVD scores (p < 0.05 and was significantly higher in hypertensive patients (p < 0.002 and lacunar stroke (p = 0.04. Hypertension (74% patients, WMH load (median = 1.5 ± 1.6% of intracranial volume, and age (mean = 65.6 years, SD = 11.3 predicted the pre/post-contrast change in normal white matter, WMH, and index stroke lesion. CSF signal increased with increasing SVD post-contrast.ConclusionA consistent general pattern of increasing textural “homogeneity” with increasing SVD and post-contrast change in CSF with increasing WMH suggest that texture analysis may be useful for the study of BBB integrity.

Microstability of TMX-U during initial thermal barrier operation

International Nuclear Information System (INIS)

Casper, T.A.; Berzins, L.V.; Ellis, R.F.; James, R.A.; Lasnier, C.

1984-03-01

During the initial thermal barrier experiments on the Tandem Mirror Experiment-Upgrade (TMX-U), we successfully demonstrated the principle of improved axial tandem mirror confinement achieved by establishment of both the thermal barrier and the ion confining potential peak. During this operation, we created both hot (100-keV) mirror-confined electron and hot (8-keV) mirror-confined ion populations in the end cells. In certain parameter ranges, we observed these species to be weakly unstable to various microinstabilities, but we did not observe clear evidence for an absolute limit to confinement

Widespread horizontal genomic exchange does not erode species barriers among sympatric ducks

NARCIS (Netherlands)

Kraus, R.H.S.; Kerstens, H.H.D.; Hooft, van W.F.; Megens, H.J.W.C.; Elmberg, J.; Tsvey, A.; Sartakov, D.; Soloviev, S.A.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Ydenberg, R.C.; Prins, H.H.T.

2012-01-01

The study of speciation and maintenance of species barriers is at the core of evolutionary biology. During speciation the genome of one population becomes separated from other populations of the same species, which may lead to genomic incompatibility with time. This separation is complete when no

Application of the Breastfeeding Personal Efficacy Beliefs Inventory and Acknowledgment of Barriers for Improving Breastfeeding Initiation Rates in an Urban Population

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Diwata Bose

2014-05-01

Full Text Available Introduction: Breastfeeding (BF is recognized as the preferred method of infant nutrition by American Academy of Pediatricians, American College of Obstetricians and Gynecologists, and the World Health Organization. Despite the benefits of BF, in 1998 only 69% of new mothers in the United States initiated BF and 29% continued to breastfeed at 6 months. Objective: To assess perceived breastfeeding confidence (BFC and determine barriers in regards to BF in an urban population. Methods: The Breastfeeding Personal Efficacy Beliefs Inventory (BPEBI was used to determine perceived BFC. The survey was distributed to 271 women during prenatal appointments at an urban Milwaukee medical center. BF initiation rate at discharge was determined by records review. A principal component factor analysis with varimax rotation was used to examine the structure of the BPEBI in this population. Results: Survey response rate was 89%. Overall BFC was 74%. BF initiation rate at discharge was 62%, exclusively BF (EBF at discharge (no bottle-feeding was 55%. In multivariate models, EBF decreased with black race (p=0.02 and with residence in the low socioeconomic status zip codes of the central city of Milwaukee (p=0.01. BFC increased with prior exposure to BF (p=0.03, EBF (p=0.03 and length of BF (p=0.02. Factor analysis identified two constructs: BFC increased with prior exposure to BF (p=0.006 and EBF (p=0.001 within the motivation construct, and BFC increased with EBF (p=0.000 within the technique/environment construct. Conclusions: The main barriers to increased BFC were lack of prior exposure to BF and nonexclusive breastfeeding practices. BF initiation rate at discharge was low compared to self-reported level of confidence. EBF decreased with black race and with closer proximity to the central city of Milwaukee.

IMS IN SMES - REASONS, ADVANTAGES AND BARRIERS ON IMPLEMENTATION

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Dragan Rajković

2008-09-01

Full Text Available Appearance of a number of management systems with various and sometimes divergent demands, demands for revise of optimal strategy on implementation of these standards in small and medium-sized enterprises (SMEs and the attempt on their integration into integrated management system are suggested even more. Firstly question on choice and reasons for implementation of standards is raised. Management and employees expect benefits on the implementation and they pass and minimize the implementation barriers. Basic concept on integrated management system (IMS into SMEs and analyse on reasons, advantages and barriers at IMS implementation are presented in this paper.

ANALYSIS OF THE COMPETITIVE MANAGEMENT OF THE SMALL AND MEDIUM COMMERCIAL COMPANIES OF ESMERALDAS, REPUBLIC OF THE ECUADOR

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Manuel Ruvin Quiñónez-Cabeza

2016-01-01

Full Text Available This paper analyzes the competitive administration of the small and medium companies of the smallest trade of Emeralds, Republic of the Ecuador. The different companies related with activities are studied that have discharge it demands in the local population. In this sense, an empiric study has been developed through 344 surveys and personal interviews carried out proprietors, administrators and workers. Finally, the most outstanding revelations in this empiric work are commented, standing out those important barriers that limit the competitiveness of the studied companies. 

Identifying key demographic parameters of a small island–associated population of Indo-Pacific bottlenose dolphins (Reunion, Indian Ocean)

Science.gov (United States)

Estrade, Vanessa; Fayan, Jacques

2017-01-01

Photo-identification surveys of Indo-Pacific bottlenose dolphins were conducted from 2009 to 2014 off Reunion Island (55°E33’/21°S07’), in the Indian Ocean. Robust Design models were applied to produce the most reliable estimate of population abundance and survival rate, while accounting for temporary emigration from the survey area (west coast). The sampling scheme consisted of a five-month (June–October) sampling period in each year of the study. The overall population size at Reunion was estimated to be 72 individuals (SE = 6.17, 95%CI = 61–85), based on a random temporary emigration (γ”) of 0.096 and a proportion of 0.70 (SE = 0.03) distinct individuals. The annual survival rate was 0.93 (±0.018 SE, 95%CI = 0.886–0.958) and was constant over time and between sexes. Models considering gender groups indicated different movement patterns between males and females. Males showed null or quasi-null temporary emigration (γ” = γ’ < 0.01), while females showed a random temporary emigration (γ”) of 0.10, suggesting that a small proportion of females was outside the survey area during each primary sampling period. Sex-specific temporary migration patterns were consistent with movement and residency patterns observed in other areas. The Robust Design approach provided an appropriate sampling scheme for deriving island-associated population parameters, while allowing to restrict survey effort both spatially (i.e. west coast only) and temporally (five months per year). Although abundance and survival were stable over the six years, the small population size of fewer than 100 individuals suggested that this population is highly vulnerable. Priority should be given to reducing any potential impact of human activity on the population and its habitat. PMID:28640918

Identifying key demographic parameters of a small island-associated population of Indo-Pacific bottlenose dolphins (Reunion, Indian Ocean).

Science.gov (United States)

Dulau, Violaine; Estrade, Vanessa; Fayan, Jacques

2017-01-01

Photo-identification surveys of Indo-Pacific bottlenose dolphins were conducted from 2009 to 2014 off Reunion Island (55°E33'/21°S07'), in the Indian Ocean. Robust Design models were applied to produce the most reliable estimate of population abundance and survival rate, while accounting for temporary emigration from the survey area (west coast). The sampling scheme consisted of a five-month (June-October) sampling period in each year of the study. The overall population size at Reunion was estimated to be 72 individuals (SE = 6.17, 95%CI = 61-85), based on a random temporary emigration (γ") of 0.096 and a proportion of 0.70 (SE = 0.03) distinct individuals. The annual survival rate was 0.93 (±0.018 SE, 95%CI = 0.886-0.958) and was constant over time and between sexes. Models considering gender groups indicated different movement patterns between males and females. Males showed null or quasi-null temporary emigration (γ" = γ' < 0.01), while females showed a random temporary emigration (γ") of 0.10, suggesting that a small proportion of females was outside the survey area during each primary sampling period. Sex-specific temporary migration patterns were consistent with movement and residency patterns observed in other areas. The Robust Design approach provided an appropriate sampling scheme for deriving island-associated population parameters, while allowing to restrict survey effort both spatially (i.e. west coast only) and temporally (five months per year). Although abundance and survival were stable over the six years, the small population size of fewer than 100 individuals suggested that this population is highly vulnerable. Priority should be given to reducing any potential impact of human activity on the population and its habitat.

Identifying key demographic parameters of a small island-associated population of Indo-Pacific bottlenose dolphins (Reunion, Indian Ocean.

Directory of Open Access Journals (Sweden)

Violaine Dulau

Full Text Available Photo-identification surveys of Indo-Pacific bottlenose dolphins were conducted from 2009 to 2014 off Reunion Island (55°E33'/21°S07', in the Indian Ocean. Robust Design models were applied to produce the most reliable estimate of population abundance and survival rate, while accounting for temporary emigration from the survey area (west coast. The sampling scheme consisted of a five-month (June-October sampling period in each year of the study. The overall population size at Reunion was estimated to be 72 individuals (SE = 6.17, 95%CI = 61-85, based on a random temporary emigration (γ" of 0.096 and a proportion of 0.70 (SE = 0.03 distinct individuals. The annual survival rate was 0.93 (±0.018 SE, 95%CI = 0.886-0.958 and was constant over time and between sexes. Models considering gender groups indicated different movement patterns between males and females. Males showed null or quasi-null temporary emigration (γ" = γ' < 0.01, while females showed a random temporary emigration (γ" of 0.10, suggesting that a small proportion of females was outside the survey area during each primary sampling period. Sex-specific temporary migration patterns were consistent with movement and residency patterns observed in other areas. The Robust Design approach provided an appropriate sampling scheme for deriving island-associated population parameters, while allowing to restrict survey effort both spatially (i.e. west coast only and temporally (five months per year. Although abundance and survival were stable over the six years, the small population size of fewer than 100 individuals suggested that this population is highly vulnerable. Priority should be given to reducing any potential impact of human activity on the population and its habitat.

Cost as a barrier to accessing dental care: findings from a Canadian population-based study.

Science.gov (United States)

Thompson, Brandy; Cooney, Peter; Lawrence, Herenia; Ravaghi, Vahid; Quiñonez, Carlos

2014-01-01

The aim of this study is to determine the demographic and socioeconomic characteristics of Canadians who report cost barriers to dental care. An analysis of data collected from the 2007/09 Canadian Health Measures Survey was undertaken from a sample of 5,586 Canadian participants aged 6-79. Cost barriers to dental care were operationalized through two questions: "In the past 12 months, have you avoided going to a dental professional because of the cost of dental care?" and "In the past 12 months, have you avoided having all the dental treatment that was recommended because of the cost?" Logistic regressions were conducted to identify relationships between covariates and positive responses to these questions. Approximately 17.3 percent of respondents had avoided a dental professional because of cost within the previous year, and 16.5 percent had declined recommended dental treatment because of cost. Adjusted estimates demonstrate that respondents with lower incomes and without dental insurance were over four times more likely to avoid a dental professional because of cost and approximately two and a half times more likely to decline recommended dental treatment because of cost. Nearly one out of five Canadians surveyed reported cost barriers to dental care. This study provides valuable baseline information for future studies to assess whether financial barriers to dental care are getting better or worse for Canadians. © 2014 American Association of Public Health Dentistry.

Understanding small business engagement in workplace violence prevention programs.

Science.gov (United States)

Bruening, Rebecca A; Strazza, Karen; Nocera, Maryalice; Peek-Asa, Corinne; Casteel, Carri

2015-01-01

Worksite wellness, safety, and violence prevention programs have low penetration among small, independent businesses. This study examined barriers and strategies influencing small business participation in workplace violence prevention programs (WVPPs). A semistructured interview guide was used in 32 telephone interviews. The study took place at the University of North Carolina Injury Prevention Research Center. Participating were a purposive sample of 32 representatives of small business-serving organizations (e.g., business membership organizations, regulatory agencies, and economic development organizations) selected for their experience with small businesses. This study was designed to inform improved dissemination of Crime Free Business (CFB), a WVPP for small, independent retail businesses. Thematic qualitative data analysis was used to identify key barriers and strategies for promoting programs and services to small businesses. Three key factors that influence small business engagement emerged from the analysis: (1) small businesses' limited time and resources, (2) low salience of workplace violence, (3) influence of informal networks and source credibility. Identified strategies include designing low-cost and convenient programs, crafting effective messages, partnering with influential organizations and individuals, and conducting outreach through informal networks. Workplace violence prevention and public health practitioners may increase small business participation in programs by reducing time and resource demands, addressing small business concerns, enlisting support from influential individuals and groups, and emphasizing business benefits of participating in the program.

Global Account of Barriers and Facilitators of Physical Activity Among Patients with Diabetes Mellitus: A Narrative Review of the Literature.

Science.gov (United States)

Adeniyi, Ade F; Anjana, Ranjit M; Weber, Mary B

2016-01-01

With diabetes rates escalating globally, there is the need for a better integration of all aspects of diabetes care for improved population outcomes. An understanding, not only of regional but global literature on physical activity barriers and its facilitators is important if healthcare providers and policy makers are to create programs tailored to their populations. Herein, we report the results of a narrative review of the global barriers and facilitators of physical activity for patients with diabetes mellitus. An in-depth literature search was conducted to identify English-language studies that examined physical activity barriers and associated facilitators among patients with diabetes mellitus. Major electronic literature databases that were searched included Google Scholar, PubMed, Hub-Med, and Highwire. Studies were available from Africa, Asia, Australia, Europe, and, predominantly North America. A total of 34 predominantly internal barriers emerged globally. The most commonly reported were time constrains, fear of provoking additional disorders, exercise venue and weather related barriers. Facilitators of physical activity were reported for most of the internal barriers (e.g. time constraints, lack of knowledge etc) while the external barriers (e.g. weather, environmental pollution etc) received only a minimal attention. Globally, patients with diabetes are confronted with an enormous number of physical activity barriers. Unlike the robust solutions proffered for the internal barriers, the literature is largely silent about solutions to the external barriers, which though fewer, may be highly influential. Additional data is needed to better understand physical activity behaviors in populations outside of North America.

Could tight junctions regulate the barrier function of the aged skin?

Science.gov (United States)

Svoboda, Marek; Bílková, Zuzana; Muthný, Tomáš

2016-03-01

The skin is known to be the largest organ in human organism creating interface with outer environment. The skin provides protective barrier against pathogens, physical and chemical insults, and against uncontrolled loss of water. The barrier function was primarily attributed to the stratum corneum (SC) but recent studies confirmed that epidermal tight junctions (TJs) also play important role in maintaining barrier properties of the skin. Independent observations indicate that barrier function and its recovery is impaired in aged skin. However, trans-epidermal water loss (TEWL) values remains rather unchanged in elderly population. UV radiation as major factor of photoageing impairs TJ proteins, but TJs have great self-regenerative potential. Since it may be possible that TJs can compensate TEWL in elderly due to its regenerative and compensatory capabilities, important question remains to be answered: how are TJs regulated during skin ageing? This review provides an insight into TJs functioning as epidermal barrier and summarizes current knowledge about the impact of ageing on the barrier function of the skin and epidermal TJs. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Integration of depression and primary care: barriers to adoption.

Science.gov (United States)

Grazier, Kyle L; Smith, Judith E; Song, Jean; Smiley, Mary L

2014-01-01

Despite the prevailing consensus as to its value, the adoption of integrated care models is not widespread. Thus, the objective of this article it to examine the barriers to the adoption of depression and primary care models in the United States. A literature search focused on peer-reviewed journal literature in Medline and PsycInfo. The search strategy focused on barriers to integrated mental health care services in primary care, and was based on previously existing searches. The search included: MeSH terms combined with targeted keywords; iterative citation searches in Scopus; searches for grey literature (literature not traditionally indexed by commercial publishers) in Google and organization websites, examination of reference lists, and discussions with researchers. Integration of depression care and primary care faces multiple barriers. Patients and families face numerous barriers, linked inextricably to create challenges not easily remedied by any one party, including the following: vulnerable populations with special needs, patient and family factors, medical and mental health comorbidities, provider supply and culture, financing and costs, and organizational issues. An analysis of barriers impeding integration of depression and primary care presents information for future implementation of services.

Locally adapted fish populations maintain small-scale genetic differentiation despite perturbation by a catastrophic flood event.

Science.gov (United States)

Plath, Martin; Hermann, Bernd; Schröder, Christiane; Riesch, Rüdiger; Tobler, Michael; García de León, Francisco J; Schlupp, Ingo; Tiedemann, Ralph

2010-08-23

Local adaptation to divergent environmental conditions can promote population genetic differentiation even in the absence of geographic barriers and hence, lead to speciation. Perturbations by catastrophic events, however, can distort such parapatric ecological speciation processes. Here, we asked whether an exceptionally strong flood led to homogenization of gene pools among locally adapted populations of the Atlantic molly (Poecilia mexicana, Poeciliidae) in the Cueva del Azufre system in southern Mexico, where two strong environmental selection factors (darkness within caves and/or presence of toxic H2S in sulfidic springs) drive the diversification of P. mexicana. Nine nuclear microsatellites as well as heritable female life history traits (both as a proxy for quantitative genetics and for trait divergence) were used as markers to compare genetic differentiation, genetic diversity, and especially population mixing (immigration and emigration) before and after the flood. Habitat type (i.e., non-sulfidic surface, sulfidic surface, or sulfidic cave), but not geographic distance was the major predictor of genetic differentiation. Before and after the flood, each habitat type harbored a genetically distinct population. Only a weak signal of individual dislocation among ecologically divergent habitat types was uncovered (with the exception of slightly increased dislocation from the Cueva del Azufre into the sulfidic creek, El Azufre). By contrast, several lines of evidence are indicative of increased flood-induced dislocation within the same habitat type, e.g., between different cave chambers of the Cueva del Azufre. The virtual absence of individual dislocation among ecologically different habitat types indicates strong natural selection against migrants. Thus, our current study exemplifies that ecological speciation in this and other systems, in which extreme environmental factors drive speciation, may be little affected by temporary perturbations, as adaptations

The impact of small irrigation diversion dams on the recent migration rates of steelhead and redband trout (Oncorhynchus mykiss)

Science.gov (United States)

Weigel, Dana E.; Connolly, Patrick J.; Powell, Madison S.

2013-01-01

Barriers to migration are numerous in stream environments and can occur from anthropogenic activities (such as dams and culverts) or natural processes (such as log jams or dams constructed by beaver (Castor canadensis)). Identification of barriers can be difficult when obstructions are temporary or incomplete providing passage periodically. We examine the effect of several small irrigation diversion dams on the recent migration rates of steelhead (Oncorhynchus mykiss) in three tributaries to the Methow River, Washington. The three basins had different recent migration patterns: Beaver Creek did not have any recent migration between sites, Libby Creek had two-way migration between sites and Gold Creek had downstream migration between sites. Sites with migration were significantly different from sites without migration in distance, number of obstructions, obstruction height to depth ratio and maximum stream gradient. When comparing the sites without migration in Beaver Creek to the sites with migration in Libby and Gold creeks, the number of obstructions was the only significant variable. Multinomial logistic regression identified obstruction height to depth ratio and maximum stream gradient as the best fitting model to predict the level of migration among sites. Small irrigation diversion dams were limiting population interactions in Beaver Creek and collectively blocking steelhead migration into the stream. Variables related to stream resistance (gradient, obstruction number and obstruction height to depth ratio) were better predictors of recent migration rates than distance, and can provide important insight into migration and population demographic processes in lotic species.

Current-induced changes of migration energy barriers in graphene and carbon nanotubes

Science.gov (United States)

Obodo, J. T.; Rungger, I.; Sanvito, S.; Schwingenschlögl, U.

2016-05-01

An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative.An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative. Electronic supplementary information (ESI) available. See DOI: 10.1039/C6NR00534A

A framework for understanding semi-permeable barrier effects on migratory ungulates

Science.gov (United States)

Sawyer, Hall; Kauffman, Matthew J.; Middleton, Arthur D.; Morrison, Thomas A.; Nielson, Ryan M.; Wyckoff, Teal B.

2013-01-01

1. Impermeable barriers to migration can greatly constrain the set of possible routes and ranges used by migrating animals. For ungulates, however, many forms of development are semi-permeable, and making informed management decisions about their potential impacts to the persistence of migration routes is difficult because our knowledge of how semi-permeable barriers affect migratory behaviour and function is limited. 2. Here, we propose a general framework to advance the understanding of barrier effects on ungulate migration by emphasizing the need to (i) quantify potential barriers in terms that allow behavioural thresholds to be considered, (ii) identify and measure behavioural responses to semi-permeable barriers and (iii) consider the functional attributes of the migratory landscape (e.g. stopovers) and how the benefits of migration might be reduced by behavioural changes. 3. We used global position system (GPS) data collected from two subpopulations of mule deer Odocoileus hemionus to evaluate how different levels of gas development influenced migratory behaviour, including movement rates and stopover use at the individual level, and intensity of use and width of migration route at the population level. We then characterized the functional landscape of migration routes as either stopover habitat or movement corridors and examined how the observed behavioural changes affected the functionality of the migration route in terms of stopover use. 4. We found migratory behaviour to vary with development intensity. Our results suggest that mule deer can migrate through moderate levels of development without any noticeable effects on migratory behaviour. However, in areas with more intensive development, animals often detoured from established routes, increased their rate of movement and reduced stopover use, while the overall use and width of migration routes decreased. 5. Synthesis and applications. In contrast to impermeable barriers that impede animal movement

Predation, Competition, and Abiotic Disturbance: Population Dynamics of Small Mammals

Energy Technology Data Exchange (ETDEWEB)

Yunger, John A. [Northern Illinois U.

1996-01-01

Predation and food availability have been implicated in annual non-cyclic fluctuations of vertebrate prey at mid-latitudes. The timing and magnitude of these factors are unclear due to a lack of large-scale field experiments, little attention to interactions, and a failure to closely link vertebrate predators with their prey. From October 1992 to January 1996, small mammal populations were censused on eight 0.6 ha plots at monthly intervals in a 32-ha prairie restoration at Fermi National Accelerator Laboratory, Illinois. Terrestrial vertebrate predators were excluded after July 1993 from four of the eight plots and canid diets monitored. Both terrestrial and avian vertebrate predators were excluded in March 1994. During 1993 small mammal densities (i.e., Microtus pennsylvanicus, Peromyscus leucopus, and P. maniculatus) were relatively high. Following peak densities in late summer, Microtus numbers were 2-3x greater on exclusion plots relative to controls due to preferential selection of Microtus by canids, as reflected in diets. Following an ice-storm and crash in small mammal numbers (particularly Microtus), vertebrate predator exclusion had no detectable effect on P. leucopus numbers, probably due to an abundance of alternative prey (i.e., Sylvilagus floridanus). Meadow vole numbers began to increase in Fall 1995, and a numerical effect of predator exclusion, similar to that in 1993, was observed. Predator exclusion had no detectable effect on the movements and spatial patterns of Microtus during 1993. There was a significant decrease in home range and a significant increase in home range overlap for £.. leucopus on the predator exclusion plots. The change in spatial behavior may be due to interspecific competition with Microtus resulting from increased densities on exclusion plots. Thus, predators had an indirect effect on .f.. leucopus spatial patterns mediated through M. pennsylvanicus. The role of food limitation was studied using natural and manipulative

Predation, Competition, and Abiotic Disturbance: Population Dynamics of Small Mammals

Energy Technology Data Exchange (ETDEWEB)

Yunger, John A.; /Northern Illinois U. /Northern Illinois U.

1996-01-01

Predation and food availability have been implicated in annual non-cyclic fluctuations of vertebrate prey at mid-latitudes. The timing and magnitude of these factors are unclear due to a lack of large-scale field experiments, little attention to interactions, and a failure to closely link vertebrate predators with their prey. From October 1992 to January 1996, small mammal populations were censused on eight 0.6 ha plots at monthly intervals in a 32-ha prairie restoration at Fermi National Accelerator Laboratory, Illinois. Terrestrial vertebrate predators were excluded after July 1993 from four of the eight plots and canid diets monitored. Both terrestrial and avian vertebrate predators were excluded in March 1994. During 1993 small mammal densities (i.e., Microtus Pennsylvanicus, Peromyscus leucopus, and P. maniculatus) were relatively high. Following peak densities in late summer, Microtus numbers wer 2-3x greater on exclusion plots relative to controls due to preferential selection of Microtus by canids, as reflected in dits. Following an ice-storm and crash in small mammal numbers (particularly Microtus), vertebrate predator exclusion had no detectable effect on P. leucopus numbers, probably due to an abundance of alternative prey (i.e., Sylvilagus floridanus). Meadow vole numbers began to increase in Fall 1995, and a numerical effect of predator exclusion, similar to that in 1993, was observed. Predator exclusion had no detectable effect on the movements and spatial patterns of Microtus during 1993. There was a significant decrease in home range and a significant increase in home range overlap for P. leucopus on the predator exclusion plots. The change in spatial behavior may be due to interspecific competition with Microtus resulting from increased densities on exclusion plots. Thus, predators had an indirect effect on P. leucopus spatial patterns mediated through M. Pennsylvanicus. The role of food limitation was studied using natural and manipulative

Consequences of severe habitat fragmentation on density, genetics, and spatial capture-recapture analysis of a small bear population.

Directory of Open Access Journals (Sweden)

Sean M Murphy

Full Text Available Loss and fragmentation of natural habitats caused by human land uses have subdivided several formerly contiguous large carnivore populations into multiple small and often isolated subpopulations, which can reduce genetic variation and lead to precipitous population declines. Substantial habitat loss and fragmentation from urban development and agriculture expansion relegated the Highlands-Glades subpopulation (HGS of Florida, USA, black bears (Ursus americanus floridanus to prolonged isolation; increasing human land development is projected to cause ≥ 50% loss of remaining natural habitats occupied by the HGS in coming decades. We conducted a noninvasive genetic spatial capture-recapture study to quantitatively describe the degree of contemporary habitat fragmentation and investigate the consequences of habitat fragmentation on population density and genetics of the HGS. Remaining natural habitats sustaining the HGS were significantly more fragmented and patchier than those supporting Florida's largest black bear subpopulation. Genetic diversity was low (AR = 3.57; HE = 0.49 and effective population size was small (NE = 25 bears, both of which remained unchanged over a period spanning one bear generation despite evidence of some immigration. Subpopulation density (0.054 bear/km2 was among the lowest reported for black bears, was significantly female-biased, and corresponded to a subpopulation size of 98 bears in available habitat. Conserving remaining natural habitats in the area occupied by the small, genetically depauperate HGS, possibly through conservation easements and government land acquisition, is likely the most important immediate step to ensuring continued persistence of bears in this area. Our study also provides evidence that preferentially placing detectors (e.g., hair traps or cameras primarily in quality habitat across fragmented landscapes poses a challenge to estimating density-habitat covariate relationships using spatial

Genetic algorithm with small population size for search feasible control parameters for parallel hybrid electric vehicles

Directory of Open Access Journals (Sweden)

Yu-Huei Cheng

2017-11-01

Full Text Available The control strategy is a major unit in hybrid electric vehicles (HEVs. In order to provide suitable control parameters for reducing fuel consumptions and engine emissions while maintaining vehicle performance requirements, the genetic algorithm (GA with small population size is applied to search for feasible control parameters in parallel HEVs. The electric assist control strategy (EACS is used as the fundamental control strategy of parallel HEVs. The dynamic performance requirements stipulated in the Partnership for a New Generation of Vehicles (PNGV is considered to maintain the vehicle performance. The known ADvanced VehIcle SimulatOR (ADVISOR is used to simulate a specific parallel HEV with urban dynamometer driving schedule (UDDS. Five population sets with size 5, 10, 15, 20, and 25 are used in the GA. The experimental results show that the GA with population size of 25 is the best for selecting feasible control parameters in parallel HEVs.

Statistical model calculations with a double-humped fission barrier GIVAB computer code

International Nuclear Information System (INIS)

Delagrange, H.; Gilat, J.

1979-01-01

Neutron and gamma emission probabilities and fission probabilities are computed, taking into account the special feature of the actinide fission barriers with two maxima. Spectra and cross sections are directly deduced from these probabilities. Populations of both wells are followed step by step. For each initial E and J, decay rates are computed and normalized in order to obtain the de-excitation probabilities imposed by the two-humped fission barrier

Facilitators and barriers experienced by federal cross-sector partners during the implementation of a healthy eating campaign.

Science.gov (United States)

Fernandez, Melissa Anne; Desroches, Sophie; Marquis, Marie; Turcotte, Mylène; Provencher, Véronique

2017-09-01

To identify facilitators and barriers that Health Canada's (HC) cross-sector partners experienced while implementing the Eat Well Campaign: Food Skills (EWC; 2013-2014) and describe how these experiences might differ according to distinct partner types. A qualitative study using hour-long semi-structured telephone interviews conducted with HC partners that were transcribed verbatim. Facilitators and barriers were identified inductively and analysed according partner types. Implementation of a national mass-media health education campaign. Twenty-one of HC's cross-sector partners (food retailers, media and health organizations) engaged in the EWC. Facilitators and barriers were grouped into seven major themes: operational elements, intervention factors, resources, collaborator traits, developer traits, partnership factors and target population factors. Four of these themes had dual roles as both facilitators and barriers (intervention factors, resources, collaborator traits and developer traits). Sub-themes identified as both facilitators and barriers illustrate the extent to which a facilitator can easily become a barrier. Partnership factors were unique facilitators, while operational and target population factors were unique barriers. Time was a barrier that was common to almost all partners regardless of partnership type. There appeared to be a greater degree of uniformity among facilitators, whereas barriers were more diverse and unique to the realities of specific types of partner. Collaborative planning will help public health organizations anticipate barriers unique to the realities of specific types of organizations. It will also prevent facilitators from becoming barriers. Advanced planning will help organizations manage time constraints and integrate activities, facilitating implementation.

Perceived barriers to leisure-time physical activity and associated factors in adolescents.

Science.gov (United States)

Dias, Douglas Fernando; Loch, Mathias Roberto; Ronque, Enio Ricardo Vaz

2015-11-01

The objective of this study was to identify the prevalence of perceived barriers to leisure-time physical activity in teenagers and to examine the possible association of these barriers with leisure-time physical inactivity. This cross-sectional study was conducted in 2011 and a representative sample of 1,409 high school students from public schools in the city of Londrina/Paraná was selected through multistage sampling. For data collection, the adolescents completed a questionnaire. The relationship between leisure-time physical inactivity (barriers was analyzed by calculating the prevalence ratio (PR) in Poisson regression models. "Lack of friends company" was the most prevalent barrier for both girls (75.8%) and boys (58.7%). "Feel lazy" for girls (PR: 1.21; CI 95%: 1.08 to 1.36) and "prefer to do other things" for the boys (PR: 1.48; CI 95%: 1.01 to 2.15) were the barriers most strongly associated with leisure-time physical inactivity. For both genders, a strong dose-response relationship was observed between the number of perceived barriers and leisure-time physical inactivity. The perception of barriers was associated with a higher prevalence of leisure-time physical inactivity in adolescents and should therefore be considered in actions for promoting physical activity in this population.The objective of this study was to identify the prevalence of perceived barriers to leisure-time physical activity in teenagers and to examine the possible association of these barriers with leisure-time physical inactivity. This cross-sectional study was conducted in 2011 and a representative sample of 1,409 high school students from public schools in the city of Londrina/Paraná was selected through multistage sampling. For data collection, the adolescents completed a questionnaire. The relationship between leisure-time physical inactivity (barriers was analyzed by calculating the prevalence ratio (PR) in Poisson regression models. "Lack of friends company" was the most

Modelling of epitaxial film growth with an Ehrlich-Schwoebel barrier dependent on the step height

International Nuclear Information System (INIS)

Leal, F F; Ferreira, S C; Ferreira, S O

2011-01-01

The formation of mounded surfaces in epitaxial growth is attributed to the presence of barriers against interlayer diffusion in the terrace edges, known as Ehrlich-Schwoebel (ES) barriers. We investigate a model for epitaxial growth using an ES barrier explicitly dependent on the step height. Our model has an intrinsic topological step barrier even in the absence of an explicit ES barrier. We show that mounded morphologies can be obtained even for a small barrier while a self-affine growth, consistent with the Villain-Lai-Das Sarma equation, is observed in the absence of an explicit step barrier. The mounded surfaces are described by a super-roughness dynamical scaling characterized by locally smooth (facetted) surfaces and a global roughness exponent α > 1. The thin film limit is featured by surfaces with self-assembled three-dimensional structures having an aspect ratio (height/width) that may increase or decrease with temperature depending on the strength of the step barrier. (fast track communication)

Genetic population structure in an equatorial sparrow: roles for culture and geography.

Science.gov (United States)

Danner, J E; Fleischer, R C; Danner, R M; Moore, I T

2017-06-01

Female preference for local cultural traits has been proposed as a barrier to breeding among animal populations. As such, several studies have found correlations between male bird song dialects and population genetics over relatively large distances. To investigate whether female choice for local dialects could act as a barrier to breeding between nearby and contiguous populations, we tested whether variation in male song dialects explains genetic structure among eight populations of rufous-collared sparrows (Zonotrichia capensis) in Ecuador. Our study sites lay along a transect, and adjacent study sites were separated by approximately 25 km, an order of magnitude less than previously examined for this and most other species. This transect crossed an Andean ridge and through the Quijos River Valley, both of which may be barriers to gene flow. Using a variance partitioning approach, we show that song dialect is important in explaining population genetics, independent of the geographic variables: distance, the river valley and the Andean Ridge. This result is consistent with the hypothesis that song acts as a barrier to breeding among populations in close proximity. In addition, songs of contiguous populations differed by the same degree or more than between two populations previously shown to exhibit female preference for local dialect, suggesting that birds from these populations would also breed preferentially with locals. As expected, all geographic variables (distance, the river valley and the Andean Ridge) also predicted population genetic structure. Our results have important implications for the understanding whether, and at what spatial scale, culture can affect population divergence. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Surface pre-treatment for barrier coatings on polyethylene terephthalate

Science.gov (United States)

Bahre, H.; Bahroun, K.; Behm, H.; Steves, S.; Awakowicz, P.; Böke, M.; Hopmann, Ch; Winter, J.

2013-02-01

Polymers have favourable properties such as light weight, flexibility and transparency. Consequently, this makes them suitable for food packaging, organic light-emitting diodes and flexible solar cells. Nonetheless, raw plastics do not possess sufficient barrier functionality against oxygen and water vapour, which is of paramount importance for most applications. A widespread solution is to deposit thin silicon oxide layers using plasma processes. However, silicon oxide layers do not always fulfil the requirements concerning adhesion and barrier performance when deposited on films. Thus, plasma pre-treatment is often necessary. To analyse the influence of a plasma-based pre-treatment on barrier performance, different plasma pre-treatments on three reactor setups were applied to a very smooth polyethylene terephthalate film before depositing a silicon oxide barrier layer. In this paper, the influence of oxygen and argon plasma pre-treatments towards the barrier performance is discussed examining the chemical and topological change of the film. It was observed that a short one-to-ten-second plasma treatment can reduce the oxygen transmission rate by a factor of five. The surface chemistry and the surface topography change significantly for these short treatment times, leading to an increased surface energy. The surface roughness rises slowly due to the development of small spots in the nanometre range. For very long treatment times, surface roughness of the order of the barrier layer's thickness results in a complete loss of barrier properties. During plasma pre-treatment, the trade-off between surface activation and roughening of the surface has to be carefully considered.

Surface pre-treatment for barrier coatings on polyethylene terephthalate

International Nuclear Information System (INIS)

Bahre, H; Böke, M; Winter, J; Bahroun, K; Behm, H; Hopmann, Ch; Steves, S; Awakowicz, P

2013-01-01

Polymers have favourable properties such as light weight, flexibility and transparency. Consequently, this makes them suitable for food packaging, organic light-emitting diodes and flexible solar cells. Nonetheless, raw plastics do not possess sufficient barrier functionality against oxygen and water vapour, which is of paramount importance for most applications. A widespread solution is to deposit thin silicon oxide layers using plasma processes. However, silicon oxide layers do not always fulfil the requirements concerning adhesion and barrier performance when deposited on films. Thus, plasma pre-treatment is often necessary. To analyse the influence of a plasma-based pre-treatment on barrier performance, different plasma pre-treatments on three reactor setups were applied to a very smooth polyethylene terephthalate film before depositing a silicon oxide barrier layer. In this paper, the influence of oxygen and argon plasma pre-treatments towards the barrier performance is discussed examining the chemical and topological change of the film. It was observed that a short one-to-ten-second plasma treatment can reduce the oxygen transmission rate by a factor of five. The surface chemistry and the surface topography change significantly for these short treatment times, leading to an increased surface energy. The surface roughness rises slowly due to the development of small spots in the nanometre range. For very long treatment times, surface roughness of the order of the barrier layer's thickness results in a complete loss of barrier properties. During plasma pre-treatment, the trade-off between surface activation and roughening of the surface has to be carefully considered. (paper)

Sampling Error in Relation to Cyst Nematode Population Density Estimation in Small Field Plots.

Science.gov (United States)

Župunski, Vesna; Jevtić, Radivoje; Jokić, Vesna Spasić; Župunski, Ljubica; Lalošević, Mirjana; Ćirić, Mihajlo; Ćurčić, Živko

2017-06-01

Cyst nematodes are serious plant-parasitic pests which could cause severe yield losses and extensive damage. Since there is still very little information about error of population density estimation in small field plots, this study contributes to the broad issue of population density assessment. It was shown that there was no significant difference between cyst counts of five or seven bulk samples taken per each 1-m 2 plot, if average cyst count per examined plot exceeds 75 cysts per 100 g of soil. Goodness of fit of data to probability distribution tested with χ 2 test confirmed a negative binomial distribution of cyst counts for 21 out of 23 plots. The recommended measure of sampling precision of 17% expressed through coefficient of variation ( cv ) was achieved if the plots of 1 m 2 contaminated with more than 90 cysts per 100 g of soil were sampled with 10-core bulk samples taken in five repetitions. If plots were contaminated with less than 75 cysts per 100 g of soil, 10-core bulk samples taken in seven repetitions gave cv higher than 23%. This study indicates that more attention should be paid on estimation of sampling error in experimental field plots to ensure more reliable estimation of population density of cyst nematodes.

New microbleed after blood-brain barrier leakage in intracerebral haemorrhage

NARCIS (Netherlands)

Nieuwenhuizen, K.M. van; Hendrikse, J.; Klijn, C.J.M.

2017-01-01

Cerebral microbleeds are increasingly recognised as biomarkers of small vessel disease. Several preclinical and clinical studies have suggested that chronic disruption of the blood-brain barrier is one of the mechanisms for the development of cerebral microbleeds.A 51-year-old man experienced two

New microbleed after blood-brain barrier leakage in intracerebral haemorrhage

NARCIS (Netherlands)

van Nieuwenhuizen, Koen M; Hendrikse, Jeroen; Klijn, Catharina J M

Cerebral microbleeds are increasingly recognised as biomarkers of small vessel disease. Several preclinical and clinical studies have suggested that chronic disruption of the blood-brain barrier is one of the mechanisms for the development of cerebral microbleeds.A 51-year-old man experienced two

[Do organizational barriers to pneumococcal and influenza vaccine access exist?].

Science.gov (United States)

Rousseau, Louise; Guay, Maryse; Archambault, Denis; El m'ala, Zahra; Abdelaziz, Nadia

2007-01-01

Despite the implementation of a Quebec immunization program against influenza and pneumococcal disease (PQIIP), vaccine coverage has remained low. There have been many studies on personal barriers to vaccination, but few have explored other kinds of barriers. To explore the presence of barriers in relation to the organization of the health care system and to propose recommendations for increasing vaccine coverage. Within a mixed protocol, a phone survey of 996 people in the target population and a case study implicating the follow-up of the PQIIP with all the site and actor categories via 43 semistructured interviews and 4 focus groups were realized. Survey data underwent a descriptive statistical analysis. Qualitative analysis followed the Miles and Huberman approach. The results indicate the presence of barriers with regard to information accessibility. These include access to: the physicians' recommendation, knowledge of the efficacy or the security of vaccines, and admissibility of clients to the PQIIP. Organizational barriers were also found to limit access to vaccination, especially in terms of restricted choices of time and location. Coordination and incentives mechanisms are not optimal. Removal of organizational barriers depends more on strategic rather than structural factors. Addressing organizational barriers should be an important component of strategies aimed at improving vaccine coverage. Public health authorities should focus on strategic management of the information and inter-organizational environment.

Smart parking barrier

KAUST Repository

Alharbi, Abdulrazaq M.

2016-05-06

Various methods and systems are provided for smart parking barriers. In one example, among others, a smart parking barrier system includes a movable parking barrier located at one end of a parking space, a barrier drive configured to control positioning of the movable parking barrier, and a parking controller configured to initiate movement of the parking barrier, via the barrier drive. The movable parking barrier can be positioned between a first position that restricts access to the parking space and a second position that allows access to the parking space. The parking controller can initiate movement of the movable parking barrier in response to a positive identification of an individual allowed to use the parking space. The parking controller can identify the individual through, e.g., a RFID tag, a mobile device (e.g., a remote control, smartphone, tablet, etc.), an access card, biometric information, or other appropriate identifier.

Surface barrier research at the Hanford Site

International Nuclear Information System (INIS)

Gee, G.W.; Ward, A.L.; Fayer, M.J.

1997-01-01

At the DOE Hanford Site, a field-scale prototype surface barrier was constructed in 1994 over an existing waste site as a part of a CERCLA treatability test. The above-grade barrier consists of a fine-soil layer overlying coarse layers of sands, gravels, basalt rock (riprap), and a low permeability asphalt layer. Two sideslope configurations, clean-fill gravel on a 10:1 slope and basalt riprap on a 2:1 slope, were built and are being tested. Design considerations included: constructability; drainage and water balance monitoring, wind and water erosion control and monitoring; surface revegetation and biotic intrusion; subsidence and sideslope stability, and durability of the asphalt layer. The barrier is currently in the final year of a three-year test designed to answer specific questions related to stability and long-term performance. One half of the barrier is irrigated such that the total water applied, including precipitation, is 480 mm/yr (three times the long-term annual average). Each year for the past two years, an extreme precipitation event (71 mm in 8 hr) representing a 1,000-yr return storm was applied in late March, when soil water storage was at a maximum. While the protective sideslopes have drained significant amounts of water, the soil cover (2-m of silt-loam soil overlying coarse sand and rock) has never drained. During the past year there was no measurable surface runoff or wind erosion. This is attributed to extensive revegetation of the surface. In addition, the barrier elevation has shown a small increase of 2 to 3 cm that is attributed to a combination of root proliferation and freeze/thaw activity. Testing will continue through September 1997. Performance data from the prototype barrier will be used by DOE in site-closure decisions at Hanford

Barriers to Electronic Commerce A doption in Small and M edium E nterprises: A C ritical L iterature R eview

OpenAIRE

Chitura T; Mupemhi S; Dube T; Bolongkikit J

2008-01-01

This study is attempting to determine if the barriers reported in early e-commerce researches differ from those found in recent e-commerce studies as well as exploring if the resultant barrier groupings created from e - commerce barriers are dissimilar. To achieve our research’s aim, an extensive literature review was conducted based on what we believe to be representative sample of some o f the most cited pieces of research on this topic. The study concludes that though ...

Isolation barriers between petunia axillaris and Petunia integrifolia (Solanaceae).

Science.gov (United States)

Dell'olivo, Alexandre; Hoballah, Maria Elena; Gübitz, Thomas; Kuhlemeier, Cris

2011-07-01

The isolation barriers restricting gene flow between populations or species are of crucial interest for understanding how biological species arise and how they are maintained. Few studies have examined the entire range of possible isolation barriers from geographic isolation to next generation hybrid viability. Here, we present a detailed analysis of isolation barriers between two flowering plant species of the genus Petunia (Solanaceae). Petunia integrifolia and P. axillaris feature divergent pollination syndromes but can produce fertile hybrids when crossed in the laboratory. Both Petunia species are primarily isolated in space but appear not to hybridize in sympatry. Our experiments demonstrate that pollinator isolation is very high but not strong enough to explain the absence of hybrids in nature. However, pollinator isolation in conjunction with male gametic isolation (i.e., pollen-pistil interaction) can explain the lack of natural hybridization, while postzygotic isolation barriers are low or nonexistent. Our study supports the notion that reproductive isolation in flowering plants is mainly caused by pre- rather than postzygotic isolation mechanisms. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Na+/K+-ATPase α1 identified as an abundant protein in the blood-labyrinth barrier that plays an essential role in the barrier integrity.

Directory of Open Access Journals (Sweden)

Yue Yang

2011-01-01

Full Text Available The endothelial-blood/tissue barrier is critical for maintaining tissue homeostasis. The ear harbors a unique endothelial-blood/tissue barrier which we term "blood-labyrinth-barrier". This barrier is critical for maintaining inner ear homeostasis. Disruption of the blood-labyrinth-barrier is closely associated with a number of hearing disorders. Many proteins of the blood-brain-barrier and blood-retinal-barrier have been identified, leading to significant advances in understanding their tissue specific functions. In contrast, capillaries in the ear are small in volume and anatomically complex. This presents a challenge for protein analysis studies, which has resulted in limited knowledge of the molecular and functional components of the blood-labyrinth-barrier. In this study, we developed a novel method for isolation of the stria vascularis capillary from CBA/CaJ mouse cochlea and provided the first database of protein components in the blood-labyrinth barrier as well as evidence that the interaction of Na(+/K(+-ATPase α1 (ATP1A1 with protein kinase C eta (PKCη and occludin is one of the mechanisms of loud sound-induced vascular permeability increase.Using a mass-spectrometry, shotgun-proteomics approach combined with a novel "sandwich-dissociation" method, more than 600 proteins from isolated stria vascularis capillaries were identified from adult CBA/CaJ mouse cochlea. The ion transporter ATP1A1 was the most abundant protein in the blood-labyrinth barrier. Pharmacological inhibition of ATP1A1 activity resulted in hyperphosphorylation of tight junction proteins such as occludin which increased the blood-labyrinth-barrier permeability. PKCη directly interacted with ATP1A1 and was an essential mediator of ATP1A1-initiated occludin phosphorylation. Moreover, this identified signaling pathway was involved in the breakdown of the blood-labyrinth-barrier resulting from loud sound trauma.The results presented here provide a novel method for

Chaotic correlations in barrier billiards with arbitrary barriers

International Nuclear Information System (INIS)

Osbaldestin, A H; Adamson, L N C

2013-01-01

We study autocorrelation functions in symmetric barrier billiards for golden mean trajectories with arbitrary barriers. Renormalization analysis reveals the presence of a chaotic invariant set and thus that, for a typical barrier, there are chaotic correlations. The chaotic renormalization set is the analogue of the so-called orchid that arises in a generalized Harper equation. (paper)

77 FR 25042 - Small Business Investment Companies-Early Stage SBICs

Science.gov (United States)

2012-04-27

... entrepreneurs' access to capital and encourage innovation as part of President Obama's Start-Up America... startups and small firms, accelerate research, and address barriers to success for entrepreneurs and small... and limit the initiative's impact on leverage fees, although fee increases will still be necessary. On...

Role of intestinal mucosal barrier in the development and progression of nonalcoholic fatty liver disease

Directory of Open Access Journals (Sweden)

ZHANG Yuanyuan

2016-12-01

Full Text Available The incidence of non-alcoholic fatty liver disease (NAFLD has been increasing year by year in China. Intestinal mucosa is the largest organ for bacterial storage, and intestinal mucosal barrier includes biological barrier, mechanical barrier, immunological barrier, and chemical barrier. This article investigates the important role of intestinal mucosal barrier function in the pathogenesis of NAFLD. As for the intestinal biological barrier, abnormalities in gut microbiota occur earlier than obesity and other metabolic disorders; small intestinal bacterial overgrowth may affect energy metabolism, promote insulin resistance, and get involved in the pathogenesis of NAFLD; regulation of gut microbiota has a certain clinical effect in the treatment of NAFLD. Intestinal mechanical barrier impairment increases the mucosal permeability and is associated with intestinal dysbacteriosis. The changes in intestinal immunological barrier may be associated with obesity, metabolic disorders, and liver inflammation. The changes in intestinal chemical barrier can inhibit the synthesis and secretion of very low-density lipoprotein and low-density lipoprotein in hepatocytes and may result in triglyceride deposition in the liver. It is pointed out that the research on intestinal mucosal barrier function provides promising prospects for the prevention and treatment of NAFLD.

Perceived unmet need and barriers to care amongst street-involved people who use illicit drugs.

Science.gov (United States)

Hyshka, Elaine; Anderson, Jalene Tayler; Wild, T Cameron

2017-05-01

Research on perceived unmet need for care for mental health and substance use problems focuses on general populations to the detriment of hidden populations. This study describes prevalence and correlates of perceived unmet need for care in a community-based sample of street-involved people who use illicit drugs and identifies barriers to care. A sample of 320 street-involved people who use drugs participated in a structured, interviewer-assisted survey in Edmonton, Canada. The survey included the Perceived Need for Care Questionnaire, which assessed unmet need for care for mental health and substance use problems across seven service types. Logistic regression examined the associations between perceived unmet need, extent of socioeconomic marginalisation and problem severity. Barriers underlying unmet service needs were also examined. Most (82%) participants reported unmet need for one or more services during the past year. Odds of reporting one or more unmet needs were elevated amongst participants reporting substantial housing instability (adjusted odds ratio = 2.37; 95% confidence interval 1.19-4.28) and amongst participants meeting criteria for drug dependence (adjusted odds ratio = 1.22; 95% confidence interval 1.03-1.50), even after adjustment for sociodemographic covariates. Structural, rather than motivational barriers were the most commonly reported reasons underlying unmet service needs. Street-involved people who use drugs experience very high rates of perceived unmet need for care for mental health and substance use problems. General population studies on perceived unmet need are insufficient for understanding needs and barriers to care in hidden populations.[Hyshka E, Anderson JT, Wild TC. Perceived unmet need and barriers to care amongst street-involved people who use illicit drugs. Drug Alcohol Rev 2017;36:295-304]. © 2016 Australasian Professional Society on Alcohol and other Drugs.

Examining barrier distributions and, in extension, energy derivative of probabilities for surrogate experiments

International Nuclear Information System (INIS)

Romain, P.; Duarte, H.; Morillon, B.

2012-01-01

The energy derivatives of probabilities are functions suited to a best understanding of certain mechanisms. Applied to compound nuclear reactions, they can bring information on fusion barrier distributions as originally introduced, and also, as presented here, on fission barrier distributions and heights. Extendedly, they permit to access the compound nucleus spin-parity states preferentially populated according to an entrance channel, at a given energy. (authors)

Small intestine epithelial barrier function is compromised in pigs with low feed intake at weaning.

NARCIS (Netherlands)

Spreeuwenberg, M.A.; Verdonk, J.M.; Gaskins, H.R.; Verstegen, M.W.A.

2001-01-01

Compromising alterations in gastrointestinal architecture are common during the weaning transition of pigs. The relation between villous atrophy and epithelial barrier function at weaning is not well understood. This study evaluated in vitro transepithelial transport by Ussing metabolic chambers,

The effect of wildfire on population dynamics for two native small mammal species in a coastal heathland in Queensland, Australia

Science.gov (United States)

Liedloff, Adam C.; Wilson, John C.; Engeman, Richard M.

2018-04-01

The influences of wildfire through population dynamics and life history for two species of small mammals in a south-east Queensland heathland on Bribie Island are presented. Trapping results provided information on breeding, immigration and movement of Melomys burtoni (Grassland melomys) and Rattus lutreolus (Swamp rat). We first investigated and optimized the design of trapping methodology for producing mark-recapture population estimates to compare two adjacent populations, one of which was subjected to an extensive wildfire during the two year study. We consider how well rodents survive wildfire and whether the immediate impacts of fire or altered habitat have the greatest impact on each species. We found the R. lutreolus population was far more influenced by the fire than the M. burtoni population both immediately after the fire and over 18 months of vegetation recovery.

Barriers to Electronic Health Record Adoption: a Systematic Literature Review.

Science.gov (United States)

Kruse, Clemens Scott; Kristof, Caitlin; Jones, Beau; Mitchell, Erica; Martinez, Angelica

2016-12-01

Federal efforts and local initiatives to increase adoption and use of electronic health records (EHRs) continue, particularly since the enactment of the Health Information Technology for Economic and Clinical Health (HITECH) Act. Roughly one in four hospitals not adopted even a basic EHR system. A review of the barriers may help in understanding the factors deterring certain healthcare organizations from implementation. We wanted to assemble an updated and comprehensive list of adoption barriers of EHR systems in the United States. Authors searched CINAHL, MEDLINE, and Google Scholar, and accepted only articles relevant to our primary objective. Reviewers independently assessed the works highlighted by our search and selected several for review. Through multiple consensus meetings, authors tapered articles to a final selection most germane to the topic (n = 27). Each article was thoroughly examined by multiple authors in order to achieve greater validity. Authors identified 39 barriers to EHR adoption within the literature selected for the review. These barriers appeared 125 times in the literature; the most frequently mentioned barriers were regarding cost, technical concerns, technical support, and resistance to change. Despite federal and local incentives, the initial cost of adopting an EHR is a common existing barrier. The other most commonly mentioned barriers include technical support, technical concerns, and maintenance/ongoing costs. Policy makers should consider incentives that continue to reduce implementation cost, possibly aimed more directly at organizations that are known to have lower adoption rates, such as small hospitals in rural areas.

Rural and small-town attitudes about alcohol use during pregnancy: a community and provider sample.

Science.gov (United States)

Logan, T K; Walker, Robert; Nagle, Laura; Lewis, Jimmie; Wiesenhahn, Donna

2003-01-01

While there has been considerable research on prenatal alcohol use, there have been limited studies focused on women in rural and small-town environments. This 2-part study examines gender differences in attitudes and perceived barriers to intervention in large community sample of persons living in rural and small-town environments in Kentucky (n = 3,346). The study also examines rural/small-town prenatal service providers' perceptions of barriers to assessment and intervention with pregnant substance abusers (n = 138). Surveys were administered to a convenience sample of employees and customers from 16 rural and small-town community outlets. There were 1503 males (45%) and 1843 females (55%) ranging in age from under 18 years old to over 66 years old. Surveys also were mailed to prenatal providers in county health departments of the 13-county study area, with 138 of 149 responding. Overall results of the community sample suggest that neither males nor females were knowledgeable about the harmful effects of alcohol use during pregnancy. Results also indicate substantial gender differences in alcohol attitudes, knowledge, and perceived barriers. Further, prenatal care providers identified several barriers in assessment and treatment of pregnant women with alcohol use problems in rural and small-town communities, including lack of knowledge and comfort with assessment as well as a lack of available and accessible treatment for referrals.

Smart parking barrier

KAUST Repository

Alharbi, Abdulrazaq M.

2016-01-01

positioning of the movable parking barrier, and a parking controller configured to initiate movement of the parking barrier, via the barrier drive. The movable parking barrier can be positioned between a first position that restricts access to the parking

The barrier to ice nucleation in monatomic water

Science.gov (United States)

Prestipino, Santi

2018-03-01

Crystallization from a supercooled liquid initially proceeds via the formation of a small solid embryo (nucleus), which requires surmounting an activation barrier. This phenomenon is most easily studied by numerical simulation, using specialized biased-sampling techniques to overcome the limitations imposed by the rarity of nucleation events. Here, I focus on the barrier to homogeneous ice nucleation in supercooled water, as represented by the monatomic-water model, which in the bulk exhibits a complex interplay between different ice structures. I consider various protocols to identify solidlike particles on a computer, which perform well enough for the Lennard-Jones model, and compare their respective impact on the shape and height of the nucleation barrier. It turns out that the effect is stronger on the nucleus size than on the barrier height. As a by-product of the analysis, I determine the structure of the nucleation cluster, finding that the relative amount of ice phases in the cluster heavily depends on the method used for classifying solidlike particles. Moreover, the phase which is most favored during the earlier stages of crystallization may happen, depending on the nucleation coordinate adopted, to be different from the stable polymorph. Therefore, the quality of a reaction coordinate cannot be assessed simply on the basis of the barrier height obtained. I explain how this outcome is possible and why it just points out the shortcoming of collective variables appropriate to simple fluids in providing a robust method of particle classification for monatomic water.

Barriers to children having a medical home in Johnson County, Iowa: notes from the field.

Science.gov (United States)

Swingle, Hanes M; Wilmoth, Ralph; Aquilino, Mary L

2008-09-01

In Iowa 70.7% of children who qualify for Title XIX and/or Title V services have a medical home, but in Johnson County, Iowa only 54.0% of such children have one. Objectives Identify barriers to access to a medical home for children who use Johnson County Public Health (JCPH) services and recommend strategies to overcome these barriers. Families with children attending JCPH well-child and WIC clinics were randomly selected to be interviewed using a semi-structured, 38-item questionnaire. Data analysis used qualitative and quantitative methodologies. Among 71 families interviewed, 41 had children without a medical home and 85% of these families cited financial barriers. Lack of U.S. citizenship accounted for 59% without health insurance. A recent move contributed to 29% not having medical homes. Nine different languages were spoken among the 41 families without a medical home. Forty-one percent of all parents interviewed had never had a medical home themselves. Many parents perceived emergency departments as more convenient than doctors' offices. Lack of health insurance, due primarily to citizenship status, is the greatest barrier to access to a medical home in this population. The migratory nature of the U.S. population, marked cultural diversity, and parental attitudes were additional barriers to children's access to a medical home. Strategies to overcome these barriers are discussed.

Exploring barriers to primary care for migrants in Greece in times of austerity: Perspectives of service providers.

Science.gov (United States)

Papadakaki, Maria; Lionis, Christos; Saridaki, Aristoula; Dowrick, Christopher; de Brún, Tomas; O'Reilly-de Brún, Mary; O'Donnell, Catherine A; Burns, Nicola; van Weel-Baumgarten, Evelyn; van den Muijsenbergh, Maria; Spiegel, Wolfgang; MacFarlane, Anne

2017-12-01

Migration in Europe is increasing at an unprecedented rate. There is an urgent need to develop 'migrant-sensitive healthcare systems'. However, there are many barriers to healthcare for migrants. Despite Greece's recent, significant experiences of inward migration during a period of economic austerity, little is known about Greek primary care service providers' experiences of delivering care to migrants. To identify service providers' views on the barriers to migrant healthcare. Qualitative study involving six participatory learning and action (PLA) focus group sessions with nine service providers. Data generation was informed by normalization process theory (NPT). Thematic analysis was applied to identify barriers to efficient migrant healthcare. Three main provider and system-related barriers emerged: (a) emphasis on major challenges in healthcare provision, (b) low perceived control and effectiveness to support migrant healthcare, and (c) attention to impoverished local population. The study identified major provider and system-related barriers in the provision of primary healthcare to migrants. It is important for the healthcare system in Greece to provide appropriate supports for communication in cross-cultural consultations for its diversifying population.

Quantifying spatial genetic structuring in mesophotic populations of the precious coral Corallium rubrum.

Science.gov (United States)

Costantini, Federica; Carlesi, Lorenzo; Abbiati, Marco

2013-01-01

While shallow water red coral populations have been overharvested in the past, nowadays, commercial harvesting shifted its pressure on mesophotic organisms. An understanding of red coral population structure, particularly larval dispersal patterns and connectivity among harvested populations is paramount to the viability of the species. In order to determine patterns of genetic spatial structuring of deep water Corallium rubrum populations, for the first time, colonies found between 58-118 m depth within the Tyrrhenian Sea were collected and analyzed. Ten microsatellite loci and two regions of mitochondrial DNA (mtMSH and mtC) were used to quantify patterns of genetic diversity within populations and to define population structuring at spatial scales from tens of metres to hundreds of kilometres. Microsatellites showed heterozygote deficiencies in all populations. Significant levels of genetic differentiation were observed at all investigated spatial scales, suggesting that populations are likely to be isolated. This differentiation may by the results of biological interactions, occurring within a small spatial scale and/or abiotic factors acting at a larger scale. Mitochondrial markers revealed significant genetic structuring at spatial scales greater then 100 km showing the occurrence of a barrier to gene flow between northern and southern Tyrrhenian populations. These findings provide support for the establishment of marine protected areas in the deep sea and off-shore reefs, in order to effectively maintain genetic diversity of mesophotic red coral populations.

Temperature dependence of interlayer coupling in perpendicular magnetic tunnel junctions with GdOX barriers

Science.gov (United States)

Newhouse-Illige, T.; Xu, Y. H.; Liu, Y. H.; Huang, S.; Kato, H.; Bi, C.; Xu, M.; LeRoy, B. J.; Wang, W. G.

2018-02-01

Perpendicular magnetic tunnel junctions with GdOX tunneling barriers have shown a unique voltage controllable interlayer magnetic coupling effect. Here, we investigate the quality of the GdOX barrier and the coupling mechanism in these junctions by examining the temperature dependence of the tunneling magnetoresistance and the interlayer coupling from room temperature down to 11 K. The barrier is shown to be of good quality with the spin independent conductance only contributing a small portion, 14%, to the total room temperature conductance, similar to AlOX and MgO barriers. The interlayer coupling, however, shows an anomalously strong temperature dependence including sign changes below 80 K. This non-trivial temperature dependence is not described by previous models of interlayer coupling and may be due to the large induced magnetic moment of the Gd ions in the barrier.

Identifying and prioritizing export barriers to small and medium enterprises (SMEs regarding food Industry based on national competition diamond Cole Porter model

Directory of Open Access Journals (Sweden)

Hossein Rahmanyyoushanlouei

2013-07-01

Full Text Available Diamond model Cole Porter and approaches after that have been used in several investigations in most countries and the credit behind the model has been repeatedly confirmed. But any theory is contended with regard to the conditions and time scope of their own; and gets corrected with the emergence of new features and based on the environment of reform. Current study has tried to identify and prioritize export barriers to small and medium enterprises (SMEs regarding food industry based on national competition diamond Cole Porter model in Iran (East Azerbaijan province and its subject pool were 266 people who were given the questionnaires. The method used to analyze and get information from research was exploratory confirmation factor, particularly from the equations structural theories for examination. With regard to the results achieved all hypotheses were confirmed.

SOUND FIELD DIFFUSIVITY AT THE TOP SURFACE OF SCHROEDER DIFFUSER BARRIERS

Directory of Open Access Journals (Sweden)

M. R. Monazzam

2006-10-01

Full Text Available Reactive barriers are one of the most promising and novel environmental noise barriers. In this case using Schroeder diffusers (e.g. quadratic residue diffusers on the top surface of the T-shape barrier was shown to significantly improve the performance of absorbent T-shape barriers. The reasons behind the high performance of diffuser barriers are considered in this investigation. A question about the diffusivity behavior of Schroeder diffusers when they are utilized on the top of barrier was raised. Diffusion coefficients of a diffuser in different conditions at some receiver locations were predicted by using a 2D boundary element method. It was found that the diffusion coefficient of diffuser at the top of barrier is so small that the diffusivity of the structure is almost the same as rigid T-shape barrier. To find the barrier’s cap behavior, the total field above the top surface of profile barriers was also predicted. It was found that the lowest total energy is at the receiver side of the cap very close to the top surface,which could demonstrate the effect of top surface on absorbing the energy as wave transfers from source edge toward the receiver side of the cap. In this case the amount of minimum total energy depends on the frequency and the configuration of the top surface. A comparison between the reductions of total field at the source side of the cap with the improvements of barrier’s performance was also done. It was shown that the amount of decrease in total field compared to that of an absorbent barrier “Ref” is directly associated to the amount of improvement in the insertion loss made by the diffuser barrier compared to the “Ref” barrier in the wide area on the ground at the shadow zone. Finally it was concluded that the diffuser on the top of barrier does not act as a diffuser and a kind of similarity between the contribution of diffuser and absorbent material on the top of T-profile barrier is seen.

Small Hydropower in the United States

Energy Technology Data Exchange (ETDEWEB)

Hadjerioua, Boualem [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Kurt [Telluride Energy, Telluride, CO (United States)

2015-09-01

Small hydropower, defined in this report as hydropower with a generating capacity of up to 10 MW typically built using existing dams, pipelines, and canals has substantial opportunity for growth. Existing small hydropower comprises about 75% of the current US hydropower fleet in terms of number of plants. The economic feasibility of developing new small hydropower projects has substantially improved recently, making small hydropower the type of new hydropower development most likely to occur. In 2013, Congress unanimously approved changes to simplify federal permitting requirements for small hydropower, lowering costs and reducing the amount of time required to receive federal approvals. In 2014, Congress funded a new federal incentive payment program for hydropower, currently worth approximately 1.5 cents/kWh. Federal and state grant and loan programs for small hydropower are becoming available. Pending changes in federal climate policy could benefit all renewable energy sources, including small hydropower. Notwithstanding remaining barriers, development of new small hydropower is expected to accelerate in response to recent policy changes.

Risk factors for frequent readmissions and barriers to transplantation in patients with cirrhosis.

Directory of Open Access Journals (Sweden)

Swaytha Ganesh

Full Text Available Hospital readmission rate is receiving increasing regulatory scrutiny. Patients with cirrhosis have high hospital readmissions rates but the relationship between frequent readmissions and barriers to transplantation remains unexplored. The goal of this study was to determine risk factors for frequent readmissions among patients with cirrhosis and identify barriers to transplantation in this population.We retrospectively reviewed medical records of 587 patients with a confirmed diagnosis of cirrhosis admitted to a large tertiary care center between May 1, 2008 and May 1, 2009. Demographics, clinical factors, and outcomes were recorded. Multivariate logistic regression was performed to identify risk factors for high readmission rates. Transplant-related factors were assessed for patients in the high readmission group.The 587 patients included in the study had 1557 admissions during the study period. A subset of 87 (15% patients with 5 or more admissions accounted for 672 (43% admissions. The factors associated with frequent admissions were non-white race (OR = 2.45, p = 0.01, diabetes (OR = 2.04, p = 0.01, higher Model for End-Stage Liver Disease (MELD score (OR = 35.10, p30 and younger age (OR = 0.98, p = 0.02. Among the 87 patients with ≥5 admissions, only 14 (16% underwent liver transplantation during the study period. Substance abuse, medical co-morbidities, and low (<15 MELD scores were barriers to transplantation in this group.A small group of patients with cirrhosis account for a disproportionately high number of hospital admissions. Interventions targeting this high-risk group may decrease frequent hospital readmissions and increase access to transplantation.

Vocal Fold Epithelial Barrier in Health and Injury A Research Review

Science.gov (United States)

Levendoski, Elizabeth Erickson; Leydon, Ciara; Thibeault, Susan L.

2015-01-01

Purpose Vocal fold epithelium is composed of layers of individual epithelial cells joined by junctional complexes constituting a unique interface with the external environment. This barrier provides structural stability to the vocal folds and protects underlying connective tissue from injury while being nearly continuously exposed to potentially hazardous insults including environmental or systemic-based irritants such as pollutants and reflux, surgical procedures, and vibratory trauma. Small disruptions in the epithelial barrier may have a large impact on susceptibility to injury and overall vocal health. The purpose of this article is to provide a broad-based review of our current knowledge of the vocal fold epithelial barrier. Methods A comprehensive review of the literature was conducted. Details of the structure of the vocal fold epithelial barrier are presented and evaluated in the context of function in injury and pathology. The importance of the epithelial-associated vocal fold mucus barrier is also introduced. Results/Conclusions Information presented in this review is valuable for clinicians and researchers as it highlights the importance of this understudied portion of the vocal folds to overall vocal health and disease. Prevention and treatment of injury to the epithelial barrier is a significant area awaiting further investigation. PMID:24686981

Proceedings of CanWEA's 2006 small wind conference

International Nuclear Information System (INIS)

2006-01-01

Small wind energy systems are typically comprised of a single wind turbine for on-site power generation of between 300 watts to 100 kW. They are suited for use in remote locations, as well as on farms or for on-grid residential applications. Small wind customers are concerned about environmental issues as well as the reliability of the electric power grid. Recent increases in electricity prices have contributed to a renewed interest in small wind systems. Primary distributed wind market growth areas include residential grid-connected sites; schools, public facilities and farmer co-operatives; and farms, business and industry. Growth in small wind applications has not been matched by an increase in government incentives, and the lack of clear technical standards for wind systems may negatively impact public perceptions of the industry. This conference provided an overview of the small wind industry in Canada. The conference provided a forum for wind industry members, government agencies, and academics to explore challenges and barriers to the growth of the small wind industry. The conference, which was held as part of the larger annual CanWEA 2006 conference and trade show, was divided into 3 sessions: (1) policies to support small wind; (2) doing business with small wind; and (3) small wind technical insights. Recommendations for the certification of small wind turbines were provided, as well as a model zoning by-law. Technical issues included the development of high penetration wind/diesel systems for isolated communities in the Arctic; technical challenges with small turbines; and siting guidelines for consumers. Several small wind turbine owners reviewed some of the challenges of both buying and using wind systems. Technical and market barriers for distributed wind applications were also discussed. The conference featured 13 presentations, of which 12 were catalogued separately for inclusion in this database. refs., tabs., figs

Status report for the Small-Tube Lysimeter Facility; Fiscal year 1992

International Nuclear Information System (INIS)

Sackschewsky, M.R.; Kemp, C.J.; Cadwell, L.L.

1993-07-01

Westinghouse Hanford Company and Pacific Northwest Laboratory are jointly developing earthen protective barriers for the near-surface disposal of radioactive and hazardous waste at the Hanford Site. The proposed barrier design consists of a blanket of fine-textured soil overlying a sequence of layers, varying from sand to basalt riprap. The experiments conducted at the Small-Tube Lysimeter Facility (STLF) were designed to measure the influence of erosion-control practices and alternate barrier layer configurations on water movement within the barrier, and extraction of water from the barrier. This report describes the results of data collected during the period from September 1988 through May 1992 at the STLF. Four concurrent experiments are being performed at this facility, each of these experiments are designed to test different components of the proposed barrier. The experiments are as follows

Barriers to lifestyle changes for prevention of cardiovascular disease

DEFF Research Database (Denmark)

Nielsen, Jesper Bo; Leppin, Anja; Gyrd-Hansen, Dorte

2017-01-01

BACKGROUND: Elimination of modifiable risk factors including unhealthy lifestyle has the potential for prevention of 80% of cardiovascular disease cases. The present study focuses on disclosing barriers for maintaining specific lifestyle changes by exploring associations between perceiving...... inequality even in populations with equal and cost-free access to health care. Our study suggests supplementing traditional public campaigns to counter cardiovascular disease by using individualized and targeted initiatives....... these barriers and various sociodemographic and health-related characteristics. METHODS: Data were collected through a web-based questionnaire survey and included 962 respondents who initially accepted treatment for a hypothetical cardiovascular risk, and who subsequently stated that they preferred lifestyle...

Small scale model and underground laboratory study of engineered barrier thermal behaviour

International Nuclear Information System (INIS)

Dardaine, M.; Beziat, A.; Gatabin, C.; Lefevre, I.; Plas, F.; Fontan, N.; Moyne, C.

1991-01-01

This is the final report of the contract CCE FI1W/0061, which had the objective of studying the thermal behaviour of the engineered barrier having the selected French clay Fo-Ca (natural calcic smectite) as its major constituent. After being installed this barrier was subjected simultaneously to the heat flux dissipated by the container and to a possible rehydration by contact with the host medium. It consists of three parts. The first part is devoted to R and D studies concerning detectors suitable for the point measurement of the water concentration. Among the techniques that can be envisaged, capacitor methods, which are very temperature sensitive, would require a great deal of effort to be satisfactory. On the other hand, the water concentration can, in principle, be derived from the measurement of the thermal conductivity in the transient regime. Although the carrying out of this measurement is somewhat critical, it can give good results under certain conditions. The second part reports experiments carried out in the laboratory concerning both the study of heat transfer during the so-called dry phase of the disposal (without any water being supplied externally) and the study of the phenomenon of fissuration. Finally, the third part describes the in situ experiment BACCHUS, carried out in the underground test facility at Mol (Belgium), in collaboration with the CEN/SCK. In the course of the five months of the thermal phase of this experiment a large variation in the amplitude of the temperature gradients was recorded, which may be explained, on one hand, by the convergence of the medium and, on the other hand, by a much more rapid rehydration than that predicted

Overcoming barriers in HPV vaccination and screening programs

Directory of Open Access Journals (Sweden)

Alex Vorsters

2017-12-01

Full Text Available The Human Papillomavirus Prevention and Control Board brought together experts to discuss optimizing HPV vaccination and screening programs.Board members reviewed the safety profile of licensed HPV vaccines based on clinical and post-marketing data, reaching a consensus that current safety data is reassuring.Successful vaccination programs used well-coordinated communication campaigns, integrating (social media to spread awareness. Communication of evidence supporting vaccine effectiveness had beneficial effects on the perception of the vaccine. However, anti-vaccination campaigns have threatened existing programs in many countries.Measurement and monitoring of HPV vaccine confidence over time could help understand the nature and scale of waning confidence, define issues and intervene appropriately using context-specific evidence-based strategies. Finally, a broad group of stakeholders, such as teachers, health care providers and the media should also be provided with accurate information and training to help support prevention efforts through enhanced understanding of the risks and benefits of vaccination.Similarly, while cervical cancer screening through population-based programs is highly effective, barriers to screening exist: awareness in countries with population-based screening programs, access for vulnerable populations, and access and affordability in low- and middle-income countries. Integration of primary and secondary prevention has the potential to accelerate the decrease in cervical cancer incidence. Keywords: (max 6 Human papillomavirus, Vaccine, Screening, Barriers, Vaccine confidence

Morphometric variations of laelapine mite (Acari: Mesostigmata populations infesting small mammals (Mammalia in Brazil

Directory of Open Access Journals (Sweden)

F. Martins-Hatano

Full Text Available The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Morphometric variations of laelapine mite (Acari: Mesostigmata) populations infesting small mammals (Mammalia) in Brazil.

Science.gov (United States)

Martins-Hatano, F; Gettinger, D; Manhães, M L; Bergallo, H G

2012-08-01

The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Barriers to lifestyle changes for prevention of cardiovascular disease - a survey among 40-60-year old Danes.

Science.gov (United States)

Nielsen, Jesper Bo; Leppin, Anja; Gyrd-Hansen, Dort E; Jarbøl, Dorte Ejg; Søndergaard, Jens; Larsen, Pia Veldt

2017-09-12

Elimination of modifiable risk factors including unhealthy lifestyle has the potential for prevention of 80% of cardiovascular disease cases. The present study focuses on disclosing barriers for maintaining specific lifestyle changes by exploring associations between perceiving these barriers and various sociodemographic and health-related characteristics. Data were collected through a web-based questionnaire survey and included 962 respondents who initially accepted treatment for a hypothetical cardiovascular risk, and who subsequently stated that they preferred lifestyle changes to medication. Logistic regression was used to analyse associations between barriers to lifestyle changes and relevant covariates. A total of 45% of respondents were identified with at least one barrier to introducing 30 min extra exercise daily, 30% of respondents reported at least one barrier to dietary change, and among smokers at least one barrier to smoking cessation was reported by 62% of the respondents. The perception of specific barriers to lifestyle change depended on sociodemographic and health-related characteristics. We observed a considerable heterogeneity between different social groups in the population regarding a number of barriers to lifestyle change. Our study demonstrates that social inequality exists in the ability to take appropriate preventive measures through lifestyle changes to stay healthy. This finding underlines the challenge of social inequality even in populations with equal and cost-free access to health care. Our study suggests supplementing traditional public campaigns to counter cardiovascular disease by using individualized and targeted initiatives.

Assessment of genetic variation among four populations of Small ...

African Journals Online (AJOL)

From the findings, it can be concluded that the SEA goats in this study showed high in population genetic variation, which implies that there is good scope for their further improvement through selection within populations. The Sukuma population, which has fairly high inbreeding, is moderately differentiated from Pare, Sonjo ...

The role of deep level traps in barrier height of 4H-SiC Schottky diode

Energy Technology Data Exchange (ETDEWEB)

Zaremba, G., E-mail: gzaremba@ite.waw.pl [Institute of Electron Technology, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Adamus, Z. [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Jung, W.; Kaminska, E.; Borysiewicz, M.A.; Korwin-Mikke, K. [Institute of Electron Technology, Al. Lotnikow 32/46, 02-668 Warsaw (Poland)

2012-09-01

This paper presents a discussion about the influence of deep level defects on the height of Ni-Si based Schottky barriers to 4H-SiC. The defects were characterized by deep level transient spectroscopy (DLTS) in a wide range of temperatures (78-750 K). The numerical simulation of barrier height value as a function of dominant defect concentration was carried out to estimate concentration, necessary to 'pin' Fermi level and thus significantly influence the barrier height. From comparison of the results of simulation with barrier height values obtained by capacitance-voltage (C-V) measurements it seems that dominant defect in measured concentration has a very small impact on the barrier height and on the increase of reverse current.

Identifying Barriers in the Use of Electronic Health Records in Hawai‘i

Science.gov (United States)

Hamamura, Faith D; Hughes, Kira

2017-01-01

Hawai‘i faces unique challenges to Electronic Health Record (EHR) adoption due to physician shortages, a widespread distribution of Medically Underserved Areas and Populations (MUA/P), and a higher percentage of small independent practices. However, research on EHR adoption in Hawai‘i is limited. To address this gap, this article examines the current state of EHR in Hawai‘i, the barriers to adoption, and the future of Health Information Technology (HIT) initiatives to improve the health of Hawai‘i's people. Eight focus groups were conducted on Lana‘i, Maui, Hawai‘i Island, Kaua‘i, Moloka‘i, and O‘ahu. In these groups, a total of 51 diverse health professionals were asked about the functionality of EHR systems, barriers to use, facilitators of use, and what EHRs would look like in a perfect world. Responses were summarized and analyzed based on constant comparative analysis techniques. Responses were then clustered into thirteen themes: system compatibility, loss of productivity, poor interface, IT support, hardware/software, patient factors, education/training, noise in the system, safety, data quality concerns, quality metrics, workflow, and malpractice concerns. Results show that every group mentioned system compatibility. In response to these findings, the Health eNet Community Health Record initiative — which allows providers web-based access to patient health information from the patient's provider network— was developed as a step toward alleviating some of the barriers to sharing information between different EHRs. The Medicare Access and CHIP Reauthorization Act of 2015 (MACRA) legislation will introduce a new payment model in 2017 that is partially based on EHR utilization. Therefore, more research should be done to understand EHR adoption and how this ruling will affect providers in Hawai‘i. PMID:28435756

Population, environment and development.

Science.gov (United States)

Karkal, M

1994-06-01

Western development models label subsistence economies, which do not participate in the market economy on a grand scale and do not consume commodities produced for and distributed through the market, to be poor. Yet, subsistence does not always indicate a low quality of life. The Western development process has destroyed wholesome and sustainable lifestyles. In India, the Green Revolution caused many small farmers to lose their land. In comparison to traditional economies, industrial economies have longer technological chains dependent on higher energy and resource inputs and exclude large numbers of people without power to buy goods. Further, they generate new and artificial needs, necessitating increased production of industrial goods and services. They erode resource bases for survival. This erosion is marginalizing people who were traditionally in nature's economy. Developed countries did not deliver 0.15% of their GNP to development projects in developing countries as promised. The US made population growth in these countries its cause. The UN and other multinational agencies during 1962-1972, at the US's request, began to support population and family planning programs in developing countries. These countries opposed the 1st draft at the 1974 Bucharest Population Conference, but by the conference in Mexico City, most supported the need for family planning. Yet, the US politicized this conference and had a greater say in the recommendations than did developing countries. Structural adjustments and external debt repayments required of developing countries in the 1980s set them back. In fact, the number of developing countries increased from 31 to 42. The UN recognizes the right to development, but social inequalities are barriers to this right. If environmental degradation continues, poverty will only increase. Women's groups are playing a great role in preparations for the International Conference on Population and Development in Cairo in September 1994.

Perceived barriers to physical activity among Polish adolescents.

Science.gov (United States)

Jodkowska, Maria; Mazur, Joanna; Oblacińska, Anna

2015-01-01

To identify barriers to physical activity (PA) for adolescents according to the gender and age and examine the association between these barriers and youths' physical activity. 3346 students aged 10-16 years (1759 girls) took part in the cross-sectional, nationally representative study. For this paper the dataset was created from adolescents who reported perceived barriers to PA, N = 2300, (1259 girls), range 13-16 years. Barriers and physical activity (MVPA) were analysed for all participants, as well as by gender, age group and place of residence. Multiple regression analysis was used to examine the relationships between perceived barriers and physical inactivity for all and than separately for boys and girls. Lack of energy, lack of time and lack of support were three of the five barriers reported by more than 40% of adolescents, statistically more likely by girls than boys and older youth than younger. For boys - lack of time (OR = 2.56; CI = 1.66-3.96), lack of skills (OR = 2.35; CI = 1.94-3.95), lack of willpower (OR = 1.71, CI = 1.05-2.80) and lack of support (OR = 1.64, CI = 1.11-2.41) were the predictors contributing to low level of PA. For girls lack of skills (OR = 3.16, CI = 1.62-6.18), lack of energy (OR = 1.84, CI = 1.14-2.96), lack of support (OR = 1.64, CI = 1.07-2.54) and lack of time (OR = 1.61,CI = 1.00-2.60) were positively and statistically significant associated with physical inactivity. 1. Perceived barriers to physical activity among adolescents have strong negative impact on recommended PA level. For girls lack of skills is the strongest predictor of low PA, for boys - lack of time. 2. Identification more precisely barriers to physical activity among adolescents will enable to developed more effective interventions in high-risk populations.

Barriers to Use of Family Planning Methods Among Heterosexual Mexican Couples.

Science.gov (United States)

Arias, María Luisa Flores; Champion, Jane Dimmitt; Soto, Norma Elva Sáenz; Tovar, Marlene; Dávila, Sandra Paloma Esparza

2017-05-01

Family planning has become increasingly important as a fundamental component of sexual health and as such is offered via public health systems worldwide. Identification of barriers to use of family planning methods among heterosexual couples living in Mexico is indicated to facilitate access to family planning methods. Barriers to family planning methods were assessed among Mexican heterosexual, sexually active males and females of reproductive age, using a modified Spanish version of the Barriers to the Use of Family Planning Methods scale (Cronbach's alpha = .89, subscales ranging from .53 to .87). Participants were recruited via convenience sampling in ambulatory care clinics within a metropolitan area in Central Mexico. Participants included 52 heterosexual couples aged 18-35 years (N = 104). Sociodemographic comparisons by gender identified older age and higher education, income, and numbers of sexual partners among men than women. More men (50%) than women (25%) were currently using family planning methods; however, 80% overall indicated intentions for its use. Overall, male condoms were used and intended for use most often by men than women. Significant gender-specific differences were found, with men (71.15%) reporting no family planning barriers, whereas women (55.66%) reported barriers including low socioeconomic status, medical concerns, and stigma. The modified Spanish translation demonstrated usefulness for measuring barriers to family planning methods use in Mexico among heterosexual males and females of reproductive age. Barriers identified by Mexican women in this study may be addressed to reduce potential barriers to family planning among Mexican populations.

Opportunities and barriers to straw construction

DEFF Research Database (Denmark)

White, Caroline Meyer; Howard, Thomas J.; Lenau, Torben Anker

2012-01-01

produced to support communication between clients and the consultants and facilitate the straw build design and decision making process. The intended audiences for the design guide are clients of small scale construction projects, architects, engineers, builders of straw construction, homeowner...... construction, and a series of qualitative interviews with a variety of stakeholders from previous straw build housing projects, results were gathered to find the most influential motives, barriers and considerations for straw build housing construction. Based on this empirical data, a design guide has been...

Deliquescence and efflorescence of small particles.

Science.gov (United States)

McGraw, Robert; Lewis, Ernie R

2009-11-21

We examine size-dependent deliquescence/efflorescence phase transformation for particles down to several nanometers in size. Thermodynamic properties of inorganic salt particles, coated with aqueous solution layers of varying thickness and surrounded by vapor, are analyzed. A thin layer criterion (TLC) is introduced to define a limiting deliquescence relative humidity (RH(D)) for small particles. This requires: (1) equality of chemical potentials between salt in an undissolved core, and thin adsorbed solution layer, and (2) equality of chemical potentials between water in the thin layer and vapor phase. The usual bulk deliquescence conditions are recovered in the limit of large dry particle size. Nanosize particles are found to deliquesce at relative humidity just below the RH(D) on crossing a nucleation barrier, located at a critical solution layer thickness. This barrier vanishes precisely at the RH(D) defined by the TLC. Concepts and methods from nucleation theory including the kinetic potential, self-consistent nucleation theory, nucleation theorems, and the Gibbs dividing surface provide theoretical foundation and point to unifying features of small particle deliquescence/efflorescence processes. These include common thermodynamic area constructions, useful for interpretation of small particle water uptake measurements, and a common free-energy surface, with constant RH cross sections describing deliquescence and efflorescence related through the nucleation theorem.

Fusion of the positive Q-value system 36S+48Ca well below the Coulomb barrier

International Nuclear Information System (INIS)

Stefanini, A. M.; Silvestri, R.; Corradi, L.; Fioretto, E.; Guiot, B.; Montagnoli, G.; Beghini, S.; Mason, P.; Scarlassara, F.; Courtin, S.; Haas, F.; Lebhertz, D.; Marginean, N.; Sagaidak, R. N.; Szilner, S.

2008-01-01

The fusion excitation function of 36 S+ 48 Ca has been measured from well above the barrier down to very small cross sections at sub-barrier energies. A steady decrease of the fusion cross sections is observed below the barrier with no pronounced change of slope. The logarithmic derivative saturates and does not reach the value expected for a constant astrophysical S-factor. The S-factor does not show any maximum in the measured energy range. Coupled-channels calculations using a Woods-Saxon potential have been performed

Subsurface barrier design alternatives for confinement and controlled advection flow

International Nuclear Information System (INIS)

Phillips, S.J.; Stewart, W.E.; Alexander, R.G.; Cantrell, K.J.; McLaughlin, T.J.

1994-02-01

Various technologies and designs are being considered to serve as subsurface barriers to confine or control contaminant migration from underground waste storage or disposal structures containing radioactive and hazardous wastes. Alternatives including direct-coupled flood and controlled advection designs are described as preconceptual examples. Prototype geotechnical equipment for testing and demonstration of these alternative designs tested at the Hanford Geotechnical Development and Test Facility and the Hanford Small-Tube Lysimeter Facility include mobile high-pressure injectors and pumps, mobile transport and pumping units, vibratory and impact pile drivers, and mobile batching systems. Preliminary laboratory testing of barrier materials and additive sequestering agents have been completed and are described

Current-induced changes of migration energy barriers in graphene and carbon nanotubes.

Science.gov (United States)

Obodo, J T; Rungger, I; Sanvito, S; Schwingenschlögl, U

2016-05-21

An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative.

Where to restore ecological connectivity? Detecting barriers and quantifying restoration benefits.

Directory of Open Access Journals (Sweden)

Brad H McRae

Full Text Available Landscape connectivity is crucial for many ecological processes, including dispersal, gene flow, demographic rescue, and movement in response to climate change. As a result, governmental and non-governmental organizations are focusing efforts to map and conserve areas that facilitate movement to maintain population connectivity and promote climate adaptation. In contrast, little focus has been placed on identifying barriers-landscape features which impede movement between ecologically important areas-where restoration could most improve connectivity. Yet knowing where barriers most strongly reduce connectivity can complement traditional analyses aimed at mapping best movement routes. We introduce a novel method to detect important barriers and provide example applications. Our method uses GIS neighborhood analyses in conjunction with effective distance analyses to detect barriers that, if removed, would significantly improve connectivity. Applicable in least-cost, circuit-theoretic, and simulation modeling frameworks, the method detects both complete (impermeable barriers and those that impede but do not completely block movement. Barrier mapping complements corridor mapping by broadening the range of connectivity conservation alternatives available to practitioners. The method can help practitioners move beyond maintaining currently important areas to restoring and enhancing connectivity through active barrier removal. It can inform decisions on trade-offs between restoration and protection; for example, purchasing an intact corridor may be substantially more costly than restoring a barrier that blocks an alternative corridor. And it extends the concept of centrality to barriers, highlighting areas that most diminish connectivity across broad networks. Identifying which modeled barriers have the greatest impact can also help prioritize error checking of land cover data and collection of field data to improve connectivity maps. Barrier detection

Self-efficacy and barriers to disaster evacuation in Hong Kong.

Science.gov (United States)

Newnham, Elizabeth A; Balsari, Satchit; Lam, Rex Pui Kin; Kashyap, Shraddha; Pham, Phuong; Chan, Emily Y Y; Patrick, Kaylie; Leaning, Jennifer

2017-12-01

To investigate specific challenges to Hong Kong's capacity for effective disaster response, we assessed perceived barriers to evacuation and citizens' self-efficacy. Global positioning system software was used to determine random sampling locations across Hong Kong, weighted by population density. The resulting sample of 1023 participants (46.5% female, mean age 40.74 years) were invited to complete questionnaires on emergency preparedness, barriers to evacuation and self-efficacy. Latent profile analysis and multinomial logistic regression were used to identify self-efficacy profiles and predictors of profile membership. Only 11% of the sample reported feeling prepared to respond to a disaster. If asked to evacuate in an emergency, 41.9% of the sample cited significant issues that would preclude them from doing so. Self-efficacy was negatively associated with barriers to disaster response so that participants reporting higher levels of self-efficacy cited fewer perceived barriers to evacuation. Hong Kong has established effective strategies for emergency response, but concerns regarding evacuation and mobilisation remain. The findings indicate that improving self-efficacy for disaster response has potential to increase evacuation readiness.

Defects in small intestinal epithelial barrier function and morphology associated with peri-weaning failure to thrive syndrome (PFTS) in swine.

Science.gov (United States)

Moeser, Adam J; Borst, Luke B; Overman, Beth L; Pittman, Jeremy S

2012-10-01

The objective of this study was to investigate intestinal function and morphology associated with peri-weaning failure to thrive syndrome (PFTS) in swine. Jejunum and distal ileum from control and pigs exhibiting PFTS was harvested at weaning, 4 and 11 days post-weaning (PW) for intestinal barrier function studies and histological analyses (n=6 pigs per group). Marked disturbances in intestinal barrier function was observed in PFTS pigs, compared with controls, indicated by lower (p<0.05) TER and increased (p<0.01) permeability to FITC dextran (4 kDa). Intestines from weaned pigs, subjected to a 4-day fast, exhibited minor disturbances in intestinal barrier function. Villus atrophy and crypt hyperplasia were observed in the PFTS intestine compared with control and fasted pigs. These data demonstrate that PFTS is associated with profound disturbances in intestinal epithelial barrier function and alterations in mucosal and epithelial morphology in which anorexia is not the sole factor. Copyright © 2012 Elsevier Ltd. All rights reserved.

Safety- barrier diagrams

DEFF Research Database (Denmark)

Duijm, Nijs Jan

2008-01-01

Safety-barrier diagrams and the related so-called 'bow-tie' diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation of safety-barrier diagrams to other methods such as fault...... trees and Bayesian networks is discussed. A simple method for quantification of safety-barrier diagrams is proposed. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk analysis with operational safety management....

Safety-barrier diagrams

DEFF Research Database (Denmark)

Duijm, Nijs Jan

2007-01-01

Safety-barrier diagrams and the related so-called "bow-tie" diagrams have become popular methods in risk analysis. This paper describes the syntax and principles for constructing consistent and valid safety-barrier diagrams. The relation with other methods such as fault trees and Bayesian networks...... are discussed. A simple method for quantification of safety-barrier diagrams is proposed, including situations where safety barriers depend on shared common elements. It is concluded that safety-barrier diagrams provide a useful framework for an electronic data structure that integrates information from risk...... analysis with operational safety management....

Community pharmacists' perceptions of barriers to communication with migrants.

Science.gov (United States)

Cleland, Jennifer A; Watson, Margaret C; Walker, Leighton; Denison, Alan; Vanes, Neil; Moffat, Mandy

2012-06-01

Effective communication by pharmacists is essential to ensure patient safety in terms of provision and use of medications by patients. Global migration trends mean community pharmacists increasingly encounter patients with a variety of first languages. The aim of this study was to explore community pharmacists' perceptions of communication barriers during the provision of care to A8 (nationals from central/Eastern European states) migrants. A qualitative face-to-face interview study of purposively sampled community pharmacists, North East Scotland. Participants (n = 14) identified a number of barriers to providing optimal care to A8 migrants including: communication (information gathering and giving); confidentiality when using family/friends as translators; the impact of patient healthcare expectations on communication and the length of the consultation; and frustration with the process of the consultation. Several barriers were specific to A8 migrants but most seemed pertinent to any group with limited English proficiency and reflect those found in studies of healthcare professionals caring for more traditional UK migrant populations. Further research is needed using objective outcome measures, such as consultation recordings, to measure the impact of these perceived barriers on pharmacist-patient consultations. Language and cultural barriers impact on the quality of pharmacist-patient communication and thus may have patient safety and pharmacist training implications. © 2011 The Authors. IJPP © 2011 Royal Pharmaceutical Society.

Chasing sympatric speciation: The relative importance and genetic basis of prezygotic isolation barriers in diverging populations of Spodoptera frugiperda

NARCIS (Netherlands)

Hänniger, S.

2015-01-01

This thesis investigates the mechanisms underlying three prezygotic isolation barriers between the corn- and the rice-strain of the noctuid moth Spodoptera frugiperda to determine possible interactions between these isolation barriers and their relative importance for sympatric speciation. First, we

Barriers to human papillomavirus vaccination among US adolescents: a systematic review of the literature.

Science.gov (United States)

Holman, Dawn M; Benard, Vicki; Roland, Katherine B; Watson, Meg; Liddon, Nicole; Stokley, Shannon

2014-01-01

Since licensure of the human papillomavirus (HPV) vaccine in 2006, HPV vaccine coverage among US adolescents has increased but remains low compared with other recommended vaccines. To systematically review the literature on barriers to HPV vaccination among US adolescents to inform future efforts to increase HPV vaccine coverage. We searched PubMed and previous review articles to identify original research articles describing barriers to HPV vaccine initiation and completion among US adolescents. Only articles reporting data collected in 2009 or later were included. Findings from 55 relevant articles were summarized by target populations: health care professionals, parents, underserved and disadvantaged populations, and males. Health care professionals cited financial concerns and parental attitudes and concerns as barriers to providing the HPV vaccine to patients. Parents often reported needing more information before vaccinating their children. Concerns about the vaccine's effect on sexual behavior, low perceived risk of HPV infection, social influences, irregular preventive care, and vaccine cost were also identified as potential barriers among parents. Some parents of sons reported not vaccinating their sons because of the perceived lack of direct benefit. Parents consistently cited health care professional recommendations as one of the most important factors in their decision to vaccinate their children. Continued efforts are needed to ensure that health care professionals and parents understand the importance of vaccinating adolescents before they become sexually active. Health care professionals may benefit from guidance on communicating HPV recommendations to patients and parents. Further efforts are also needed to reduce missed opportunities for HPV vaccination when adolescents interface with the health care system. Efforts to increase uptake should take into account the specific needs of subgroups within the population. Efforts that address system

"Population and poverty: major barriers to food accessibility" -- a panel discussion on civil society and people's participation.

Science.gov (United States)

1996-01-01

This paper summarizes conference statements on poverty and food policies that were made by parliamentary members from Malaysia, the Philippines, and India. These presentations were made after the main panel discussion on barriers to food accessibility. In Malaysia the government adopted a National Agricultural Policy in 1984. This policy encouraged increased productivity, effective use of resources, agricultural credit and incentives, and integrated pest management. Strong support was given to the food processing industry. Poverty was the main reason for food inaccessibility. Through government efforts, poverty was reduced from 16.5% in 1990 to 8.9% in 1995. The Filipino member reported that government efforts had focused on national campaigns to combat hunger and to encourage community participation. The government was forced to implement a national Plan of Action for Food Security due to increased population, environmental degradation, closing land frontiers, and the global economy. The Plan encouraged increases in productivity, price and supply stabilization, maintenance of stocks, and rice subsidies for the poor. Gender concerns were being incorporated into development programs. The Indian member linked food insecurity to world resource problems. He stated that food problems included imbalances between supply and demand, but more importantly inequalities in access to food and differences in nutritional content of food. Populations in developing countries spent a larger proportion of income on food of lesser quality and variety that contributed to nutritional deficiencies, particularly among women and children. Food insecurity was part of the cycle of poverty, hunger, low productivity, and high mortality. Poverty was the primary cause and a major consequence of hunger and chronic food insecurity. Although India increased food productivity, food insecurity remained. Multidisciplinary approaches are needed.

Reactive diffusion in Sc/Si multilayer X-ray mirrors with CrB2 barrier layers

International Nuclear Information System (INIS)

Pershyn, Y.P.; Zubarev, E.N.; Kondratenko, V.V.; Sevryukova, V.A.; Kurbatova, S.V.

2011-01-01

Processes undergoing in Sc/Si multilayer X-ray mirrors (MXMs) with periods of ∝27 nm and barrier layers of CrB 2 0.3- and 0.7-nm thick within the temperature range of 420-780 K were studied by methods of small-angle X-ray reflectivity (λ=0.154 nm) and cross-sectional transmission electron microscopy. All layers with the exception of Sc ones are amorphous. Barrier layers are stable at least up to a temperature of 625 K and double the activation energy of diffusional intermixing at moderate temperatures. Introduction of barriers improves the thermal stability of Sc/Si MXMs at least by 80 degrees. Diffusion of Si atoms through barrier layers into Sc layers with formation of silicides was shown to be the main degradation mechanism of MXMs. A comparison of the stability for Sc/Si MXMs with different barriers published in the literature is conducted. The ways of further improvement of barrier properties are discussed. (orig.)

Vehicle barrier systems

International Nuclear Information System (INIS)

Sena, P.A.

1986-01-01

The ground vehicle is one of the most effective tools available to an adversary force. Vehicles can be used to penetrate many types of perimeter barriers, transport equipment and personnel rapidly over long distances, and deliver large amounts of explosives directly to facilities in suicide missions. The function of a vehicle barrier system is to detain or disable a defined threat vehicle at a selected distance from a protected facility. Numerous facilities are installing, or planning to install, vehicle barrier systems and many of these facilities are requesting guidance to do so adequately. Therefore, vehicle barriers are being evaluated to determine their stopping capabilities so that systems can be designed that are both balanced and capable of providing a desired degree of protection. Equally important, many of the considerations that should be taken into account when establishing a vehicle barrier system have been identified. These considerations which pertain to site preparation, barrier selection, system integration and operation, and vehicle/barrier interaction, are discussed in this paper

Barriers to adapt eCommerce by rural microenterprises in Sweden : a case study

OpenAIRE

Sandberg, Karl W; Håkansson, Fredrik

2014-01-01

Research has shown that small and medium-sized enterprises (SMEs) are rapidly adopting the e-commerce. However, there is nearly no research into how microenterprises are adopting eCommerce. Present paper focus on microenterprise adaption of eCommerce in terms of barriers in relation to already known research on SMEs. A case study, carried out by 12 microenterprises to find out barriers to adapt eCommerce had been done. The empirical results show that the microenterprises share most of the bar...

DIRECTIONS OF DEVELOPMENT OF SMALL AND MEDIUM ENTERPRISES IN POLAND

Directory of Open Access Journals (Sweden)

Joanna Szwacka-Mokrzycka

2013-09-01

Full Text Available The private sector, dominated by small and medium enterprises (SME, has been rapidly developing in Poland. Small and medium enterprises are defined as economic entities hiring not more than 250 employees and have turnovers lower than 50 million euros per year. The functioning of small and medium enterprises supports a decrease in unemployment, contributes to introduction of innovative operations and products as well as significantly influences GDP generation. The SME sector faces many barriers limiting their development. They include mainly social, financial and law barriers. Operations of the Polish Agency for Enterprise Development, Academic Business Incubators and other entities support small entrepreneurship. Recently, marketing in small and medium enterprises has particularly influenced their survival. A marketing programme consists of four elements a product, price, distribution, and promotion and is described as the marketing mix. In the paper, results of research in randomly selected enterprises of the SME sector are presented. The aim of the research was to diagnose a range of marketing operations’ use in these companies. The conducted research displays that marketing activity is used mainly for promotion in the investigated enterprises and to a small extent for managing a product’s portfolio in a firm. 

Disability inclusion in primary health care in Nepal: an explorative study of perceived barriers to access governmental health services.

NARCIS (Netherlands)

Hees, S. van; Cornielje, H.; Wagle, P.; Veldman, E.

2014-01-01

Purpose: Persons with disabilities face additional barriers in accessing primary healthcare services, especially in developing countries. Consequently the prevalence of secondary health conditions is higher among this population. This study aims to explore the perceived barriers to access primary

Extensive population genetic structure in the giraffe

Directory of Open Access Journals (Sweden)

Grether Gregory F

2007-12-01

Full Text Available Abstract Background A central question in the evolutionary diversification of large, widespread, mobile mammals is how substantial differentiation can arise, particularly in the absence of topographic or habitat barriers to dispersal. All extant giraffes (Giraffa camelopardalis are currently considered to represent a single species classified into multiple subspecies. However, geographic variation in traits such as pelage pattern is clearly evident across the range in sub-Saharan Africa and abrupt transition zones between different pelage types are typically not associated with extrinsic barriers to gene flow, suggesting reproductive isolation. Results By analyzing mitochondrial DNA sequences and nuclear microsatellite loci, we show that there are at least six genealogically distinct lineages of giraffe in Africa, with little evidence of interbreeding between them. Some of these lineages appear to be maintained in the absence of contemporary barriers to gene flow, possibly by differences in reproductive timing or pelage-based assortative mating, suggesting that populations usually recognized as subspecies have a long history of reproductive isolation. Further, five of the six putative lineages also contain genetically discrete populations, yielding at least 11 genetically distinct populations. Conclusion Such extreme genetic subdivision within a large vertebrate with high dispersal capabilities is unprecedented and exceeds that of any other large African mammal. Our results have significant implications for giraffe conservation, and imply separate in situ and ex situ management, not only of pelage morphs, but also of local populations.

Facilitators and Barriers to Health-Seeking Behaviours among Filipino Migrants: Inductive Analysis to Inform Health Promotion

Directory of Open Access Journals (Sweden)

D. Maneze

2015-01-01

Full Text Available Understanding factors that influence health-seeking behaviour of migrants is necessary to intervene for behaviour change. This paper explores Filipino migrants’ perceptions of facilitators and barriers to maintaining health in Australia. Open-ended survey item responses reflecting factors that assisted and hindered health following migration to Australia were inductively analysed. Three hundred and thirty-seven of the 552 survey respondents (61% provided open-ended responses. Responses were grouped into two major categories: individual factors, including personal resources and cultural influences, and environmental factors encompassing both the physical conditions in the host country and health service access. Awareness of practices that enhance health was a major personal facilitator of health-seeking behaviour; however, competing priorities of daily living were perceived as barriers. Cultural beliefs and practices influenced health-seeking behaviour. Despite high self-rated English language skills in this population, new migrants and the elderly cited communication difficulties as barriers to accessing health services. Insight into facilitators and barriers to health-seeking behaviour in this less researched migrant population revealed tools for enhancing engagement in health promotion programs addressing healthy lifestyle.

Facilitators and Barriers to Health-Seeking Behaviours among Filipino Migrants: Inductive Analysis to Inform Health Promotion.

Science.gov (United States)

Maneze, D; DiGiacomo, M; Salamonson, Y; Descallar, J; Davidson, P M

2015-01-01

Understanding factors that influence health-seeking behaviour of migrants is necessary to intervene for behaviour change. This paper explores Filipino migrants' perceptions of facilitators and barriers to maintaining health in Australia. Open-ended survey item responses reflecting factors that assisted and hindered health following migration to Australia were inductively analysed. Three hundred and thirty-seven of the 552 survey respondents (61%) provided open-ended responses. Responses were grouped into two major categories: individual factors, including personal resources and cultural influences, and environmental factors encompassing both the physical conditions in the host country and health service access. Awareness of practices that enhance health was a major personal facilitator of health-seeking behaviour; however, competing priorities of daily living were perceived as barriers. Cultural beliefs and practices influenced health-seeking behaviour. Despite high self-rated English language skills in this population, new migrants and the elderly cited communication difficulties as barriers to accessing health services. Insight into facilitators and barriers to health-seeking behaviour in this less researched migrant population revealed tools for enhancing engagement in health promotion programs addressing healthy lifestyle.

Facilitators and Barriers to Health-Seeking Behaviours among Filipino Migrants: Inductive Analysis to Inform Health Promotion

Science.gov (United States)

Salamonson, Y.; Descallar, J.; Davidson, P. M.

2015-01-01

Understanding factors that influence health-seeking behaviour of migrants is necessary to intervene for behaviour change. This paper explores Filipino migrants' perceptions of facilitators and barriers to maintaining health in Australia. Open-ended survey item responses reflecting factors that assisted and hindered health following migration to Australia were inductively analysed. Three hundred and thirty-seven of the 552 survey respondents (61%) provided open-ended responses. Responses were grouped into two major categories: individual factors, including personal resources and cultural influences, and environmental factors encompassing both the physical conditions in the host country and health service access. Awareness of practices that enhance health was a major personal facilitator of health-seeking behaviour; however, competing priorities of daily living were perceived as barriers. Cultural beliefs and practices influenced health-seeking behaviour. Despite high self-rated English language skills in this population, new migrants and the elderly cited communication difficulties as barriers to accessing health services. Insight into facilitators and barriers to health-seeking behaviour in this less researched migrant population revealed tools for enhancing engagement in health promotion programs addressing healthy lifestyle. PMID:26380277

Reactive barrier technologies for treatment of contaminated groundwater at Rocky Flats

International Nuclear Information System (INIS)

Marozas, D.C.; Bujewski, G.E.; Castaneda, N.

1997-01-01

The U.S. Department of Energy (DOE) Office of Science and Technology Subsurface Contaminants Focus Area is supporting the investigation of reactive barrier technologies to mitigate the risks associated with mixed organic/radioactive waste at several DOE sites. Groundwater from a small contaminated plume at the Rocky Flats Environmental Technology Site (RFETS) is being used to evaluate passive reactive material treatment. Permeable reactive barriers which intercept contaminants and destroy the VOC component while containing radionuclides are attractive for a number of reasons relating to public and regulatory acceptance. In situ treatment keeps contaminants away from the earth's surface, there is no above-ground treatment equipment that could expose workers and the public and operational costs are expected to be lower than currently used technologies. This paper will present results from preliminary site characterization and in-field small-scale column testing of reactive materials at RFETS. Successful demonstration is expected to lead to full-scale implementation of the technology at several DOE sites, including Rocky Flats

Modeling mechanical inhomogeneities in small populations of proliferating monolayers and spheroids.

Science.gov (United States)

Lejeune, Emma; Linder, Christian

2018-06-01

Understanding the mechanical behavior of multicellular monolayers and spheroids is fundamental to tissue culture, organism development, and the early stages of tumor growth. Proliferating cells in monolayers and spheroids experience mechanical forces as they grow and divide and local inhomogeneities in the mechanical microenvironment can cause individual cells within the multicellular system to grow and divide at different rates. This differential growth, combined with cell division and reorganization, leads to residual stress. Multiple different modeling approaches have been taken to understand and predict the residual stresses that arise in growing multicellular systems, particularly tumor spheroids. Here, we show that by using a mechanically robust agent-based model constructed with the peridynamic framework, we gain a better understanding of residual stresses in multicellular systems as they grow from a single cell. In particular, we focus on small populations of cells (1-100 s) where population behavior is highly stochastic and prior investigation has been limited. We compare the average strain energy density of cells in monolayers and spheroids using different growth and division rules and find that, on average, cells in spheroids have a higher strain energy density than cells in monolayers. We also find that cells in the interior of a growing spheroid are, on average, in compression. Finally, we demonstrate the importance of accounting for stochastic fluctuations in the mechanical environment, particularly when the cellular response to mechanical cues is nonlinear. The results presented here serve as a starting point for both further investigation with agent-based models, and for the incorporation of major findings from agent-based models into continuum scale models when explicit representation of individual cells is not computationally feasible.

Genomic selection in small dairy cattle populations

DEFF Research Database (Denmark)

Thomasen, Jørn Rind

on optimization of genomc selction for a small dairy cattle breed such as Danish Jersey. Implementing genetic superior breeding schemes thus requires more accurate genomc predictions. Besides international collaboration, genotyping of cows is an efficient way to obtain more accurate genomic predictions...

Investigations of thermal barrier coatings of turbine parts using gas flame heating

Science.gov (United States)

Lepeshkin, A. R.; Bichkov, N. G.; Ilinskaja, O. I.; Nazarov, V. V.

2017-09-01

The development of methods for the calculated and experimental investigations thermal barrier coatings and thermal state of gas-turbine engine parts with a thermal barrier coatings is actual work. The gas flame heating was demonstrated to be effectively used during investigations of a thermal ceramic barrier coatings and thermal state of such gas-turbine engine parts with a TBC as the cooled turbine blades and vanes and combustion liner components. The gas-flame heating is considered to be preferable when investigating the gas-turbine engine parts with a TBC in the special cases when both the convective and radiant components of thermal flow are of great importance. The small-size rig with gas-flame flow made it possible to conduct the comparison investigations with the purpose of evaluating the efficiency of thermal protection of the ceramic deposited thermal barrier coatings on APS and EB techniques. The developed design-experiment method was introduced in bench tests of turbine blades and combustion liner components of gas turbine engines.

Emergent Behavior of Coupled Barrier Island - Resort Systems

Science.gov (United States)

McNamara, D. E.; Werner, B. T.

2004-12-01

Barrier islands are attractive sites for resorts. Natural barrier islands experience beach erosion and island overwash during storms, beach accretion and dune building during inter-storm periods, and migration up the continental shelf as sea level rises. Beach replenishment, artificial dune building, seawalls, jetties and groins have been somewhat effective in protecting resorts against erosion and overwash during storms, but it is unknown how the coupled system will respond to long-term sea level rise. We investigate coupled barrier island - resort systems using an agent-based model with three components: natural barrier islands divided into a series of alongshore cells; resorts controlled by markets for tourism and hotel purchases; and coupling via storm damage to resorts and resort protection by government agents. Modeled barrier islands change by beach erosion, island overwash and inlet cutting during storms, and beach accretion, tidal delta growth and dune and vegetation growth between storms. In the resort hotel market, developer agents build hotels and hotel owning agents purchase them using predictions of future revenue and property appreciation, with the goal of maximizing discounted utility. In the tourism market, hotel owning agents set room rental prices to maximize profit and tourist agents choose vacation destinations maximizing a utility based on beach width, price and word-of-mouth. Government agents build seawalls, groins and jetties, and widen the beach and build up dunes by adding sand to protect resorts from storms, enhance beach quality, and maximize resort revenue. Results indicate that barrier islands and resorts evolve in a coupled manner to resort size saturation, with resorts protected against small-to-intermediate-scale storms under fairly stable sea level. Under extended, rapidly rising sea level, protection measures enhance the effect of large storms, leading to emergent behavior in the form of limit cycles or barrier submergence

Small-scale genetic structure in an endangered wetland specialist: possible effects of landscape change and population recovery

Science.gov (United States)

van Rees, Charles B.; Reed, J. Michael; Wilson, Robert E.; Underwood, Jared G.; Sonsthagen, Sarah A.

2018-01-01

The effects of anthropogenic landscape change on genetic population structure are well studied, but the temporal and spatial scales at which genetic structure can develop, especially in taxa with high dispersal capabilities like birds, are less well understood. We investigated population structure in the Hawaiian gallinule (Gallinula galeata sandvicensis), an endangered wetland specialist bird on the island of O`ahu (Hawai`i, USA). Hawaiian gallinules have experienced a gradual population recovery from near extinction in the 1950s, and have recolonized wetlands on O`ahu in the context of a rapidly urbanizing landscape. We genotyped 152 Hawaiian gallinules at 12 microsatellite loci and sequenced a 520 base-pair fragment of the ND2 region of mitochondrial DNA (mtDNA) from individuals captured at 13 wetland locations on O`ahu in 2014–2016. We observed moderate to high genetic structuring (overall microsatellite FST = 0.098, mtDNA FST = 0.248) among populations of Hawaiian gallinules occupying wetlands at very close geographic proximity (e.g., 1.5–55 km). Asymmetry in gene flow estimates suggests that Hawaiian gallinules may have persisted in 2–3 strongholds which served as source populations that recolonized more recently restored habitats currently supporting large numbers of birds. Our results highlight that genetic structure can develop in taxa that are expanding their range after severe population decline, and that biologically significant structuring can occur over small geographic distances, even in avian taxa.

Health Care Experiences and Perceived Barriers to Health Care Access: A Qualitative Study Among African Migrants in Guangzhou, Guangdong Province, China.

Science.gov (United States)

Lin, Lavinia; Brown, Katherine B; Yu, Fan; Yang, Jingqi; Wang, Jason; Schrock, Joshua M; Bodomo, Adams B; Yang, Ligang; Yang, Bin; Nehl, Eric J; Tucker, Joseph D; Wong, Frank Y

2015-10-01

Guangzhou, one of China's largest cities and a main trading port in South China, has attracted many African businessmen and traders migrating to the city for financial gains. Previous research has explored the cultural and economic roles of this newly emerging population; however, little is known about their health care experiences while in China. Semi-structured interviews and focus groups were used to assess health care experiences and perceived barriers to health care access among African migrants in Guangzhou, China. Overall, African migrants experienced various barriers to accessing health care and were dissatisfied with local health services. The principal barriers to care reported included affordability, legal issues, language barriers, and cultural differences. Facing multiple barriers, African migrants have limited access to care in Guangzhou. Local health settings are not accustomed to the African migrant population, suggesting that providing linguistically and culturally appropriate services may improve access to care for the migrants.

Barriers to Physical Activity Among African American Women: An Integrative Review of the Literature

OpenAIRE

Joseph, Rodney P.; Ainsworth, Barbara E.; Keller, Colleen; Dodgson, Joan E

2015-01-01

A key aspect for researchers to consider when developing culturally appropriate physical activity (PA) interventions for African American (AA) women are the specific barriers AA women face that limit their participation in PA. Identification and critical examination of these barriers is the first step in developing comprehensive culturally relevant approaches to promote PA and help resolve PA-related health disparities in this underserved population. We conducted a systemati...

Provider-identified barriers and facilitators to implementing a supported employment program in spinal cord injury.

Science.gov (United States)

Cotner, Bridget A; Ottomanelli, Lisa; O'Connor, Danielle R; Trainor, John K

2018-06-01

In a 5-year study, individual placement and support (IPS) significantly increased employment rate of United States Veterans with spinal cord injury (SCI), a historically underemployed population. In a follow-up study, data on barriers and facilitators to IPS implementation were identified. Over 24 months of implementation, 82 key medical and vocational staff underwent semi-structured interviews (n = 130). Interviews were digitally recorded and qualitatively analyzed (ATLAS.ti v0.7) using a constant comparative method to generate themes. Some barriers to implementation occurred throughout the study, such as Veterans' lack of motivation and providers' difficulty integrating vocational and medical rehabilitation. Other barriers emerged at specific stages, for example, early barriers included a large geographic service area and a large patient caseload, and late barriers included need for staff education. Facilitators were mostly constant throughout implementation and included leadership support and successful integration of vocational staff into the medical care team. Implementation strategies need to be adjusted as implementation progresses and matures. The strategies that succeeded in this setting, which were situated in a real-world context of providing IPS as a part of SCI medical care, may inform implementation of IPS for other populations with physical disabilities. Implications for Rehabilitation Key facilitators to IPS in SCI implementation are integrating vocational staff with expertise in IPS and SCI on clinical rehabilitation teams and providing leadership support. Ongoing barriers to IPS in SCI include patient specific and program administration factors such as caseload size and staffing patterns. Varying implementation strategies are needed to address barriers as they arise and facilitate successful implementation.

Paleoclassical transport explains electron transport barriers in RTP and TEXTOR

Energy Technology Data Exchange (ETDEWEB)

Hogeweij, G M D [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, PO Box 1207, NL-3430 BE Nieuwegein (Netherlands); Callen, J D [University of Wisconsin, Madison, WI 53706-1609 (United States)

2008-06-15

The recently developed paleoclassical transport model sets the minimum level of electron thermal transport in a tokamak. This transport level has proven to be in good agreement with experimental observations in many cases when fluctuation-induced anomalous transport is small, i.e. in (near-)ohmic plasmas in small to medium size tokamaks, inside internal transport barriers (ITBs) or edge transport barriers (H-mode pedestal). In this paper predictions of the paleoclassical transport model are compared in detail with data from such kinds of discharges: ohmic discharges from the RTP tokamak, EC heated RTP discharges featuring both dynamic and shot-to-shot scans of the ECH power deposition radius and off-axis EC heated discharges from the TEXTOR tokamak. For ohmically heated RTP discharges the T{sub e} profiles predicted by the paleoclassical model are in reasonable agreement with the experimental observations, and various parametric dependences are captured satisfactorily. The electron thermal ITBs observed in steady state EC heated RTP discharges and transiently after switch-off of off-axis ECH in TEXTOR are predicted very well by the paleoclassical model.

Consequences of dispersal for the quantitative study of adaptation in small-scale plots: a case study of an avian island population

NARCIS (Netherlands)

Lambrechts, M.M.; Visser, M.E.; Verboven, N.

2000-01-01

Lifetime recruitment of breeding offspring estimated in small- scale study plots (i.e local recruitment) is considered to be the best available ecological measure of contributions to following generations, and sufficient for the quantitative study of adaptation in natural populations. Recent

Potential corridors and barriers for plague spread in central Asia

Science.gov (United States)

2013-01-01

Background Plague (Yersinia pestis infection) is a vector-borne disease which caused millions of human deaths in the Middle Ages. The hosts of plague are mostly rodents, and the disease is spread by the fleas that feed on them. Currently, the disease still circulates amongst sylvatic rodent populations all over the world, including great gerbil (Rhombomys opimus) populations in Central Asia. Great gerbils are social desert rodents that live in family groups in burrows, which are visible on satellite images. In great gerbil populations an abundance threshold exists, above which plague can spread causing epizootics. The spatial distribution of the host species is thought to influence the plague dynamics, such as the direction of plague spread, however no detailed analysis exists on the possible functional or structural corridors and barriers that are present in this population and landscape. This study aims to fill that gap. Methods Three 20 by 20 km areas with known great gerbil burrow distributions were used to analyse the spatial distribution of the burrows. Object-based image analysis was used to map the landscape at several scales, and was linked to the burrow maps. A novel object-based method was developed – the mean neighbour absolute burrow density difference (MNABDD) – to identify the optimal scale and evaluate the efficacy of using landscape objects as opposed to square cells. Multiple regression using raster maps was used to identify the landscape-ecological variables that explain burrow density best. Functional corridors and barriers were mapped using burrow density thresholds. Cumulative resistance of the burrow distribution to potential disease spread was evaluated using cost distance analysis. A 46-year plague surveillance dataset was used to evaluate whether plague spread was radially symmetric. Results The burrow distribution was found to be non-random and negatively correlated with Greenness, especially in the floodplain areas. Corridors and

The consequences of translational and rotational entropy lost by small molecules on binding to proteins

Science.gov (United States)

Murray, Christopher W.; Verdonk, Marcel L.

2002-10-01

When a small molecule binds to a protein, it loses a significant amount of rigid body translational and rotational entropy. Estimates of the associated energy barrier vary widely in the literature yet accurate estimates are important in the interpretation of results from fragment-based drug discovery techniques. This paper describes an analysis that allows the estimation of the rigid body entropy barrier from the increase in binding affinities that results when two fragments of known affinity and known binding mode are joined together. The paper reviews the relatively rare number of examples where good quality data is available. From the analysis of this data, we estimate that the barrier to binding, due to the loss of rigid-body entropy, is 15-20 kJ/mol, i.e. around 3 orders of magnitude in affinity at 298 K. This large barrier explains why it is comparatively rare to observe multiple fragments binding to non-overlapping adjacent sites in enzymes. The barrier is also consistent with medicinal chemistry experience where small changes in the critical binding regions of ligands are often poorly tolerated by enzymes.

Pathogen reduction requirements for direct potable reuse in Antarctica: evaluating human health risks in small communities.

Science.gov (United States)

Barker, S Fiona; Packer, Michael; Scales, Peter J; Gray, Stephen; Snape, Ian; Hamilton, Andrew J

2013-09-01

Small, remote communities often have limited access to energy and water. Direct potable reuse of treated wastewater has recently gained attention as a potential solution for water-stressed regions, but requires further evaluation specific to small communities. The required pathogen reduction needed for safe implementation of direct potable reuse of treated sewage is an important consideration but these are typically quantified for larger communities and cities. A quantitative microbial risk assessment (QMRA) was conducted, using norovirus, giardia and Campylobacter as reference pathogens, to determine the level of treatment required to meet the tolerable annual disease burden of 10(-6) DALYs per person per year, using Davis Station in Antarctica as an example of a small remote community. Two scenarios were compared: published municipal sewage pathogen loads and estimated pathogen loads during a gastroenteritis outbreak. For the municipal sewage scenario, estimated required log10 reductions were 6.9, 8.0 and 7.4 for norovirus, giardia and Campylobacter respectively, while for the outbreak scenario the values were 12.1, 10.4 and 12.3 (95th percentiles). Pathogen concentrations are higher under outbreak conditions as a function of the relatively greater degree of contact between community members in a small population, compared with interactions in a large city, resulting in a higher proportion of the population being at risk of infection and illness. While the estimates of outbreak conditions may overestimate sewage concentration to some degree, the results suggest that additional treatment barriers would be required to achieve regulatory compliance for safe drinking water in small communities. Copyright © 2013 Elsevier B.V. All rights reserved.

Quantifying spatial genetic structuring in mesophotic populations of the precious coral Corallium rubrum.

Directory of Open Access Journals (Sweden)

Federica Costantini

Full Text Available While shallow water red coral populations have been overharvested in the past, nowadays, commercial harvesting shifted its pressure on mesophotic organisms. An understanding of red coral population structure, particularly larval dispersal patterns and connectivity among harvested populations is paramount to the viability of the species. In order to determine patterns of genetic spatial structuring of deep water Corallium rubrum populations, for the first time, colonies found between 58-118 m depth within the Tyrrhenian Sea were collected and analyzed. Ten microsatellite loci and two regions of mitochondrial DNA (mtMSH and mtC were used to quantify patterns of genetic diversity within populations and to define population structuring at spatial scales from tens of metres to hundreds of kilometres. Microsatellites showed heterozygote deficiencies in all populations. Significant levels of genetic differentiation were observed at all investigated spatial scales, suggesting that populations are likely to be isolated. This differentiation may by the results of biological interactions, occurring within a small spatial scale and/or abiotic factors acting at a larger scale. Mitochondrial markers revealed significant genetic structuring at spatial scales greater then 100 km showing the occurrence of a barrier to gene flow between northern and southern Tyrrhenian populations. These findings provide support for the establishment of marine protected areas in the deep sea and off-shore reefs, in order to effectively maintain genetic diversity of mesophotic red coral populations.

Barriers to fusion

International Nuclear Information System (INIS)

Berriman, A.C.; Butt, R.D.; Dasgupta, M.; Hinde, D.J.; Morton, C.R.; Newton, J.O.

1999-01-01

The fusion barrier is formed by the combination of the repulsive Coulomb and attractive nuclear forces. Recent research at the Australian National University has shown that when heavy nuclei collide, instead of a single fusion barrier, there is a set of fusion barriers. These arise due to intrinsic properties of the interacting nuclei such deformation, rotations and vibrations. Thus the range of barrier energies depends on the properties of both nuclei. The transfer of matter between nuclei, forming a neck, can also affect the fusion process. High precision data have been used to determine fusion barrier distributions for many nuclear reactions, leading to new insights into the fusion process

Extremal surface barriers

International Nuclear Information System (INIS)

Engelhardt, Netta; Wall, Aron C.

2014-01-01

We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy

Identification of alkaptonuria in the general population: a United Kingdom experience describing the challenges, possible solutions and persistent barriers.

Science.gov (United States)

Ranganath, L; Taylor, A M; Shenkin, A; Fraser, W D; Jarvis, J; Gallagher, J A; Sireau, N

2011-06-01

Progress in research into rare diseases is challenging. This paper discusses strategies to identify individuals with the rare genetic disease alkaptonuria (AKU) within the general population. Strategies used included a questionnaire survey of general practitioners, a dedicated website and patient network contact, targeted family screening and medical conference targeting. Primary care physicians of the UK were targeted by a postal survey that involved mailing 11,151 UK GPs; the response rate was 18.2%. We have identified 75 patients in the UK with AKU by the following means: postal survey (23), targeted family screening (11), patient networks and the website (41). Targeting medical conferences (AKU, rare diseases, rheumatology, clinical biochemistry, orthopaedics, general practitioners) did not lead to new identification in the UK but helped identify overseas cases. We are now aware of 626 patients worldwide including newly identified non-UK people with AKU in the following areas: Slovakia (208), the rest of Europe (including Turkey) (79), North America (including USA and Canada) (110), and the rest of the world (154). A mechanism for identifying individuals with AKU in the general population-not just in the UK but worldwide-has been established. Knowledge of patients with AKU, both in the UK and outside, is often confined to establishing their location in a particular GP practice or association with a particular medical professional. Mere identification, however, does not always lead to full engagement for epidemiological research purposes or targeting treatment since further barriers exist.

Current-induced changes of migration energy barriers in graphene and carbon nanotubes

KAUST Repository

Obodo, Tobechukwu Joshua

2016-04-29

An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative. © 2016 The Royal Society of Chemistry.

Beliefs, Barriers and Facilitators to Physical Activity in Bariatric Surgery Candidates.

Science.gov (United States)

Zabatiero, Juliana; Hill, Kylie; Gucciardi, Daniel F; Hamdorf, Jeffrey M; Taylor, Susan F; Hagger, Martin S; Smith, Anne

2016-05-01

Bariatric surgery candidates engage in less physical activity (PA) and spend longer periods in sedentary behaviour (SB) when compared to the general adult population. The aim of this study was to explore the beliefs about PA and perceived barriers and facilitators to PA in obese adults scheduled for bariatric surgery. Nineteen obese adults (15 females), with a mean (SD) age of 41.6 (12.1) years, weight of 119.2 (20.5) kg and body mass index of 41.6 (6.7) kg/m(2) participated in a one-on-one in-depth qualitative interview before undergoing bariatric surgery. Data were analysed using inductive thematic analysis. Most participants believed that engaging in regular PA confers important health benefits, however reported insufficient PA levels to obtain those benefits. The perceived barriers to PA reported by participants were both obesity related (e.g. bodily pain, physical limitation and self-presentational concerns) and non-obesity related (e.g. lack of motivation, environment and restricted resources). All participants stated weight loss to be the main perceived facilitator to PA, together with social factors, better time management and access to financial resources. In bariatric surgery candidates, many of the perceived barriers and facilitators to PA are not obesity related and are therefore unlikely to change as a result of bariatric surgery. This may explain why earlier research shows little change in PA or SB following surgery. It is likely that an approach that aims to address the barriers and facilitators identified in this study is needed to change the inactive lifestyle adopted in this population.

Barriers to Care Among Transgender and Gender Nonconforming Adults.

Science.gov (United States)

Gonzales, Gilbert; Henning-Smith, Carrie

2017-12-01

Policy Points: Transgender and gender nonconforming (GNC) adults may experience barriers to care for a variety of reasons, including discrimination and lack of awareness by providers in health care settings. In our analysis of a large, population-based sample, we found transgender and GNC adults were more likely to be uninsured and have unmet health care needs, and were less likely to have routine care, compared to cisgender (nontransgender) women. Our findings varied by gender identity. More research is needed on transgender and GNC populations, including on how public policy and provider awareness affects health care access and health outcomes differentially by gender identity. Very little population-based research has examined health and access to care among transgender populations. This study compared barriers to care between cisgender, transgender, and gender nonconforming (GNC) adults using data from a large, multistate sample. We used data from the 2014-2015 Behavioral Risk Factor Surveillance System to estimate the prevalence of having no health insurance, unmet medical care needs due to cost, no routine checkup, and no usual source of care for cisgender women (n = 183,370), cisgender men (n = 131,080), transgender women (n = 724), transgender men (n = 449), and GNC adults (n = 270). Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for each barrier to care while adjusting for sociodemographic characteristics. Transgender and GNC adults were more likely to be nonwhite, sexual minority, and socioeconomically disadvantaged compared to cisgender adults. After controlling for sociodemographic characteristics, transgender women were more likely to have no health insurance (OR = 1.60; 95% CI = 1.07-2.40) compared to cisgender women; transgender men were more likely to have no health insurance (OR = 2.02; 95% CI = 1.25-3.25) and no usual source of care (OR = 1.84; 95% CI = 1.18-2.88); and GNC

The effect of feeding position and body size on the capacity of small ...

African Journals Online (AJOL)

The effect of feeding position and body size on the capacity of small ruminants to reach, for food when fed through barriers. ... The barrier allowed the neck to pass through, but not the shoulders. It was hypothesized that goats would have larger reach than sheep and that for each species, horizontal reach forwards, F, ...

Urea uptake enhances barrier function and antimicrobial defense in humans by regulating epidermal gene expression

Science.gov (United States)

Grether-Beck, Susanne; Felsner, Ingo; Brenden, Heidi; Kohne, Zippora; Majora, Marc; Marini, Alessandra; Jaenicke, Thomas; Rodriguez-Martin, Marina; Trullas, Carles; Hupe, Melanie; Elias, Peter M.; Krutmann, Jean

2012-01-01

Urea is an endogenous metabolite, known to enhance stratum corneum hydration. Yet, topical urea anecdotally also improves permeability barrier function, and it appears to exhibit antimicrobial activity. Hence, we hypothesized that urea is not merely a passive metabolite, but a small-molecule regulator of epidermal structure and function. In 21 human volunteers, topical urea improved barrier function in parallel with enhanced antimicrobial peptide (LL-37 and β-defensin-2) expression. Urea both stimulates expression of, and is transported into keratinocytes by two urea transporters, UT-A1 and UT-A2, and by aquaporin 3, 7 and 9. Inhibitors of these urea transporters block the downstream biological effects of urea, which include increased mRNA and protein levels for: (i) transglutaminase-1, involucrin, loricrin and filaggrin; (ii) epidermal lipid synthetic enzymes, and (iii) cathelicidin/LL-37 and β-defensin-2. Finally, we explored the potential clinical utility of urea, showing that topical urea applications normalized both barrier function and antimicrobial peptide expression in a murine model of atopic dermatitis (AD). Together, these results show that urea is a small-molecule regulator of epidermal permeability barrier function and antimicrobial peptide expression after transporter uptake, followed by gene regulatory activity in normal epidermis, with potential therapeutic applications in diseased skin. PMID:22418868

Addressing geographic access barriers to emergency care services: a national ecologic study of hospitals in Brazil.

Science.gov (United States)

Rocha, Thiago Augusto Hernandes; da Silva, Núbia Cristina; Amaral, Pedro Vasconcelos; Barbosa, Allan Claudius Queiroz; Rocha, João Victor Muniz; Alvares, Viviane; de Almeida, Dante Grapiuna; Thumé, Elaine; Thomaz, Erika Bárbara Abreu Fonseca; de Sousa Queiroz, Rejane Christine; de Souza, Marta Rovery; Lein, Adriana; Lopes, Daniel Paulino; Staton, Catherine A; Vissoci, João Ricardo Nickenig; Facchini, Luiz Augusto

2017-08-22

Unequal distribution of emergency care services is a critical barrier to be overcome to assure access to emergency and surgical care. Considering this context it was objective of the present work analyze geographic access barriers to emergency care services in Brazil. A secondary aim of the study is to define possible roles to be assumed by small hospitals in the Brazilian healthcare network to overcome geographic access challenges. The present work can be classified as a cross-sectional ecological study. To carry out the present study, data of all 5843 Brazilian hospitals were categorized among high complexity centers and small hospitals. The geographical access barriers were identified through the use of two-step floating catchment area method. Once concluded the previous step an evaluation using the Getis-Ord-Gi method was performed to identify spatial clusters of municipalities with limited access to high complexity centers but well covered by well-equipped small hospitals. The analysis of accessibility index of high complexity centers highlighted large portions of the country with nearly zero hospital beds by inhabitant. In contrast, it was possible observe a group of 1595 municipalities with high accessibility to small hospitals, simultaneously with a low coverage of high complexity centers. Among the 1595 municipalities with good accessibility to small hospitals, 74% (1183) were covered by small hospitals with at least 60% of minimum emergency service requirements. The spatial clusters analysis aggregated 589 municipalities with high values related to minimum emergency service requirements. Small hospitals in these 589 cities could promote the equity in access to emergency services benefiting more than eight million people. There is a spatial disequilibrium within the country with prominent gaps in the health care network for emergency services. Taking this challenge into consideration, small hospitals could be a possible solution and foster equity in access

Facilitators and Barriers for Successful Breastfeeding Among Migrant Chuukese Mothers on Guam

Directory of Open Access Journals (Sweden)

Kathryn M. Wood PhD, RNC-OB

2017-01-01

Full Text Available The aim of this study was to identify factors that serve as facilitators and barriers for breastfeeding among Chuukese immigrant women living in Guam. Traditionally, Chuukese women exclusively breastfeed their babies; however, it is reported that breastfeeding decreases among these women when they migrate to Guam. Little is known about why this happens. A qualitative approach that included key informant interviews and focus groups of Chuukese women ( N  = 24 who had migrated to Guam and delivered a baby on Guam within the past 5 years was completed. The project interview or discussion guides were guided by the Theory of Reasoned Action and explored facilitators and barriers for successful breastfeeding among these Chuukese immigrant women. Among this population, key facilitators for breastfeeding included high levels of self-confidence, family support, knowledge about breastfeeding, and the existence of strong traditional Chuukese cultural values. Key barriers included experiences of cultural conflict or social change, lack of support from their local community, family and health-care staff, as well as limited self-knowledge about how to manage common breastfeeding problems. Where more facilitators were reported, breastfeeding was more often practiced, and where more barriers were reported, formula feeding was more likely. Social factors, health system policies, and proactive nursing support are important influencing factors for breastfeeding among the Chuukese immigrant population on Guam. Nursing can play key roles in policy, professional leadership and practice, and social advocacy to support breastfeeding promotion and maintenance on Guam.

High-Risk Smoking Behaviors and Barriers to Smoking Cessation Among Homeless Individuals.

Science.gov (United States)

Chen, Joseph S; Nguyen, Austin Huy; Malesker, Mark A; Morrow, Lee E

2016-05-01

Although tobacco practices and the effects of tobacco use among the general American population are well described, minimal data exist regarding tobacco use and barriers to smoking cessation among homeless individuals. Anonymous, voluntary surveys based on a previously implemented instrument were completed by 100 smoking individuals residing at a homeless shelter. These surveys assessed high-risk smoking behaviors and respondents' perceived barriers to long-term smoking cessation. Ninety percent of study participants reported engaging in at least one of the high-risk tobacco practices. Nicotine replacement therapy was perceived by respondents to be the most desired form of smoking cessation aid. Excessive stress with use of tobacco smoking to alleviate stress and anxiety was the most significant self-perceived barrier to smoking cessation. High-risk tobacco practices are remarkably common among smoking homeless individuals. Despite literature consistently showing that non-nicotine tobacco cessation pharmacotherapies (varenicline, buproprion) have higher smoking cessation rates, nicotine replacement monotherapy was perceived as more valuable by survey respondents. Although lack of financial resources was expected to be the biggest barrier to successful cessation, social stressors and the use of smoking to cope with homelessness were perceived as a greater obstacle in this cohort. Given the paucity of data on the long-term effects of the high-risk tobacco behaviors reported by these homeless smokers, this study highlights the need for further investigations regarding tobacco use and tobacco cessation in this vulnerable population. Copyright © 2016 by Daedalus Enterprises.

Multilayer moisture barrier

Science.gov (United States)

Pankow, Joel W; Jorgensen, Gary J; Terwilliger, Kent M; Glick, Stephen H; Isomaki, Nora; Harkonen, Kari; Turkulainen, Tommy

2015-04-21

A moisture barrier, device or product having a moisture barrier or a method of fabricating a moisture barrier having at least a polymer layer, and interfacial layer, and a barrier layer. The polymer layer may be fabricated from any suitable polymer including, but not limited to, fluoropolymers such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), or ethylene-tetrafluoroethylene (ETFE). The interfacial layer may be formed by atomic layer deposition (ALD). In embodiments featuring an ALD interfacial layer, the deposited interfacial substance may be, but is not limited to, Al.sub.2O.sub.3, AlSiO.sub.x, TiO.sub.2, and an Al.sub.2O.sub.3/TiO.sub.2 laminate. The barrier layer associated with the interfacial layer may be deposited by plasma enhanced chemical vapor deposition (PECVD). The barrier layer may be a SiO.sub.xN.sub.y film.

Total quality management: Strengths and barriers to implementation and cultural adaptation

Science.gov (United States)

Siegfeldt, Denise V.; Glenn, Michael; Hamilton, Louise

1992-01-01

NASA/Langley Research Center (LaRC) is in the process of implementing Total Quality Management (TQM) throughout the organization in order to improve productivity and make the Center an even better place to work. The purpose of this project was to determine strengths and barriers to TQM being implemented and becoming a part of the organizational culture of the Human Resources Management Division (HRMD) at Langley. The target population for this project was both supervisory and nonsupervisory staff of the HMRD. In order to generate data on strengths and barriers to TQM implementation and cultural adaptation, a modified nominal group technique was used.

Development of Permeable Reactive Barriers (PRB) Using Edible Oils

Science.gov (United States)

2008-06-01

naturally occurring processes of advection and dispersion to bring the contaminants to the treatment barrier. A large scale approach would be to form a...process has been developed for distributing soybean oil as an oil-in-water emulsion consisting of small oil droplets dispersed in a continuous...Thiele Kaolin Company, Sandersville, Georgia) was added to certain materials to evaluate the effect of increasing clay content. Grain size

Barriers to providing maternity care to women with physical disabilities: Perspectives from health care practitioners.

Science.gov (United States)

Mitra, Monika; Smith, Lauren D; Smeltzer, Suzanne C; Long-Bellil, Linda M; Sammet Moring, Nechama; Iezzoni, Lisa I

2017-07-01

Women with physical disabilities are known to experience disparities in maternity care access and quality, and communication gaps with maternity care providers, however there is little research exploring the maternity care experiences of women with physical disabilities from the perspective of their health care practitioners. This study explored health care practitioners' experiences and needs around providing perinatal care to women with physical disabilities in order to identify potential drivers of these disparities. We conducted semi-structured telephone interviews with 14 health care practitioners in the United States who provide maternity care to women with physical disabilities, as identified by affiliation with disability-related organizations, publications and snowball sampling. Descriptive coding and content analysis techniques were used to develop an iterative code book related to barriers to caring for this population. Public health theory regarding levels of barriers was applied to generate broad barrier categories, which were then analyzed using content analysis. Participant-reported barriers to providing optimal maternity care to women with physical disabilities were grouped into four levels: practitioner level (e.g., unwillingness to provide care), clinical practice level (e.g., accessible office equipment like adjustable exam tables), system level (e.g., time limits, reimbursement policies), and barriers relating to lack of scientific evidence (e.g., lack of disability-specific clinical data). Participants endorsed barriers to providing optimal maternity care to women with physical disabilities. Our findings highlight the needs for maternity care practice guidelines for women with physical disabilities, and for training and education regarding the maternity care needs of this population. Copyright © 2016 Elsevier Inc. All rights reserved.

The Schottky energy barrier dependence of charge injection in organic light-emitting diodes

Science.gov (United States)

Campbell, I. H.; Davids, P. S.; Smith, D. L.; Barashkov, N. N.; Ferraris, J. P.

1998-04-01

We present device model calculations of the current-voltage (I-V) characteristics of organic diodes and compare them with measurements of structures fabricated using MEH-PPV. The structures are designed so that all of the current is injected from one contact. The I-V characteristics are considered as a function of the Schottky energy barrier to charge injection from the contact. Experimentally, the Schottky barrier is varied from essentially zero to more than 1 eV by using different metal contacts. A consistent description of the device I-V characteristics is obtained as the Schottky barrier is varied from small values, less than about 0.4 eV, where the current flow is space-charge limited to larger values where it is contact limited.

Dealing with barriers to energy efficiency and SMEs: Some empirical evidences

International Nuclear Information System (INIS)

Trianni, A.; Cagno, E.

2012-01-01

This paper aims at providing an identification and an analysis of the most relevant barriers to energy efficiency that limit a widespread implementation of the Best Available Technologies and Practices (BAT/Ps) through the investigation of 128 non-energy intensive manufacturing Small and Medium-sized Enterprises (SMEs) in Northern Italy. The study, starting from the existing literature, performs an investigation of the operational difficulties occurring when it has been decided to undertake the process of investing resources in energy efficiency interventions. The most perceived barriers have been analyzed with respect to several important characteristics (among others, sector and firm’s size). This examination shows also that very much attention should be paid to avoid bundling together SMEs of different sizes and sectors, since different behaviors with respect to the perception of the barriers can be observed. The analysis of the sample presents some interesting trends considering the perception of the barriers with respect to previous experience of the enterprises on energy efficiency. The paper also explores, through a preliminary analysis, the correlations among questions in order to understand the dynamics and the possible effects of a given barrier with respect to others. Several suggestions for future research in this important area have been provided. -- Highlights: ► Evidences of different behaviors with respect to energy efficiency among sectors and firm’s size (within SMEs). ► Importance, for energy efficiency barriers, of avoid bundling SMEs as a whole. ► Preliminary investigation of relationships between barriers in order to understand the dynamics.

Facilitators and barriers of implementing enhanced recovery in colorectal surgery at a safety net hospital: A provider and patient perspective.

Science.gov (United States)

Alawadi, Zeinab M; Leal, Isabel; Phatak, Uma R; Flores-Gonzalez, Juan R; Holihan, Julie L; Karanjawala, Burzeen E; Millas, Stefanos G; Kao, Lillian S

2016-03-01

Enhanced Recovery After Surgery (ERAS) pathways are known to decrease complications and duration of stay in colorectal surgery patients. However, it is unclear whether an ERAS pathway would be feasible and effective at a safety-net hospital. The aim of this study was to identify local barriers and facilitators before the adoption of an ERAS pathway for patients undergoing colorectal operations at a safety-net hospital. Semistructured interviews were conducted to assess the perceived barriers and facilitators before ERAS adoption. Stratified purposive sampling was used. Interviews were audiotaped, transcribed verbatim, and analyzed using content analysis. Analytic and investigator triangulation were used to establish credibility. Interviewees included 8 anesthesiologists, 5 surgeons, 6 nurses, and 18 patients. Facilitators identified across the different medical professions were (1) feasibility and alignment with current practice, (2) standardization of care, (3) smallness of community, (4) good teamwork and communication, and (5) caring for patients. The barriers were (1) difficulty in adapting to change, (2) lack of coordination between different departments, (3) special needs of a highly comorbid and socioeconomically disadvantaged patient population, (4) limited resources, and (5) rotating residents. Facilitators identified by the patients were (1) welcoming a speedy recovery, (2) being well-cared for and satisfied with treatment, (3) adequate social support, (4) welcoming early mobilization, and (5) effective pain management. The barriers were (1) lack of quiet and private space, (2) need for more patient education and counseling, and (3) unforeseen complications. Although limited hospital resources are perceived as a barrier to ERAS implementation at a safety-net hospital, there is strong support for such pathways and multiple factors were identified that may facilitate change. Inclusion of patient perspectives is critical to identifying challenges and

200-BP-1 Prototype Hanford Barrier Annual Monitoring Report for Fiscal Year 2004

Energy Technology Data Exchange (ETDEWEB)

Ward, Andy L.; Linville, Jenifer K.; Keller, Jason M.; Seedahmed, Gamal H.

2005-01-03

considerable cost savings without any loss in accuracy. A relatively high coverage of native plants still persists after the initial revegetation in 1994. The formerly irrigated treatments continue to show greater cover of grasses and litter than the non-irrigated treatments. On the formerly irrigated treatments, the mean cover class was 25 to 50 percent for both grasses and shrubs. On the non-irrigated treatments, the mean cover class was 5 to 25 percent from grasses and 25 to 50 percent for shrubs. Species diversity of the vegetative community appears to have stabilized over the past several years. In addition to 12 of 17 species present in 2003 being present in 2004, two additional species were encountered. Sagebrush continues to flourish with shrubs along the perimeter showing higher biomass yield than the interior shrubs. There is evidence of sagebrush seedlings recruitment but not of rabbitbrush; the presence of gray rabbitbrush appears is declining as the barrier surface continues to stabilize. Use of the barrier surface by insects and small mammals is also evident. Small mammal burrowing on the barrier surface has become more prevalent in recent years, suggesting that the restored barrier surface is beginning to function as a recovering ecosystem. Small-mammal burrowing on the top and sides of the barrier is most prevalent on the finer-grained and disturbed soils while active ant mounds were observed on the northern and western slopes.

Adrenergic-induced enhancement of brain barrier system permeability to small nonelectrolytes: choroid plexus versus cerebral capillaries

International Nuclear Information System (INIS)

Murphy, V.A.; Johanson, C.E.

1985-01-01

Acute hypertension induced by adrenergic agents opens up the blood-CSF barrier (choroid plexus) to nonelectrolyte and protein tracers. Sprague-Dawley adult rats anesthetized with ketamine were given an intravenous bolus of either epinephrine (10 micrograms/kg), phenylephrine (100 micrograms/kg), isoproterenol (10 micrograms/kg), or D,L-amphetamine (2 mg/kg). Tracers were injected simultaneously with test agents, and the animals killed 10 min later. Epinephrine raised MABP by 57 mm Hg, to a peak pressure of 160 mm Hg; and it increased the volume of distribution (Vd) of urea, mannitol, and 125 I-bovine serum albumin in CSF by 1.5-, 2.7-, and 30-fold, respectively. There was enhanced uptake by lateral and fourth ventricle choroid plexuses, cerebral cortex, cerebellum, medulla, and thalamus. Phenylephrine also elevated MABP to 160 mm Hg, but it increased permeation of tracers into CSF (and several brain regions) to a lesser extent than epinephrine, attributable to protective vasoconstriction associated with alpha-agonist activity. Ratio analysis of Vd data provides evidence that augmented permeation of nonelectrolyte tracers in acute hypertension occurs predominantly by diffusion rather than vesicular transport. It is postulated that elevated MABP distends the central cores of choroid plexus villi and cerebral capillaries, with resultant stretching and opening of tight junctions in both barrier systems; with less hindrance to diffusion, urea and mannitol are cleared at rates closer to free diffusion. Neither isoproterenol (decreased MABP by 40 mm Hg) nor amphetamine (did not alter MABP) significantly opened the choroid plexus or blood-brain barrier to tracers

Thresholds to access the market for small-scale energy consumers

International Nuclear Information System (INIS)

Baarsma, B.; Bremer, S.; De Nooij, M.; Poort, J.

2007-10-01

Entry of and options for expansion are import aspects for a well-functioning free market. The Netherlands Competition Authority (NMa)/The Office of Energy Regulation (DTe/Energiekamer) received signals that there are barriers for entering or further growth on the small consumer market. The regulator has asked SEO Economic Research to examine which entry barriers are significant and require further monitoring. For this purpose, more than 20 interviews were held with market parties and stakeholders. [mk] [nl

A qualitative analysis of multi-level barriers to HIV testing among women in Lebanon.

Science.gov (United States)

Clark, Kirsty A; Keene, Danya E; Pachankis, John E; Fattal, Omar; Rizk, Nesrine; Khoshnood, Kaveh

2017-09-01

While the number of HIV cases in the Middle East and North Africa region is low compared to other regions, recent studies show that incidence is increasing especially among high-risk populations; in particular, little is known about women and HIV in the region. Through semi-structured interviews with sexual healthcare providers and staff at non-governmental organisations, we sought to understand barriers to HIV testing among women in Lebanon. Using snowball sampling, key informants were recruited from greater Beirut (12 physicians, 9 non-governmental organisation staff). Data were analysed using a grounded theory framework. Findings identified barriers to HIV testing among women at each level of an adapted social-ecological model (i.e. social-cultural barriers, policy barriers, interpersonal healthcare provider barriers and intrapersonal barriers). Primary findings include the culture of sex as taboo; lack of sexual health education among women; fear of disclosing HIV testing and diagnosis; financial barriers linked to stigmatising insurance policies; and provider attitudes towards women. Findings can be used to inform HIV-related sexual health interventions at multiple levels for women in Lebanon and the greater region.

Overcoming language and cultural barriers: a graphical communication tool to perform a parasitological screening in two vulnerable populations from Argentina.

Science.gov (United States)

Buyayisqui, María Pía; Bordoni, Noemí; Garbossa, Graciela

2013-01-01

This is an exploratory study of the application of a support tool for the detection of asymptomatic subjects carrying enteric parasites in two vulnerable populations in Argentina: a shantytown in the city of Buenos Aires and a rural Wichí indigenous community in the province of Chaco. The ethnic and cultural diversity, high illiteracy rate, and language barriers called for the development of an auxiliary resource to explain stool sample collection procedures. In individual interviews with each family, the authors used two instructional guidance leaflets in comic strip format depicting the procedures. They evaluated the acceptance of the graphical communication tool on the basis of the number of retrieved samples. Percentages of respondent families were 72.2% and 66.7%, respectively. Definitive validation of these instruments would allow their use in community studies, community service learning experiences, and research on aboriginal communities that would otherwise be excluded from studies on health status.

Pharmacologic studies in vulnerable populations: Using the pediatric experience.

Science.gov (United States)

Zimmerman, Kanecia; Gonzalez, Daniel; Swamy, Geeta K; Cohen-Wolkowiez, Michael

2015-11-01

Historically, few data exist to guide dosing in children and pregnant women. Multiple barriers to inclusion of these vulnerable populations in clinical trials have led to this paucity of data. However, federal legislation targeted at pediatric therapeutics, innovative clinical trial design, use of quantitative clinical pharmacology methods, pediatric thought leadership, and collaboration have successfully overcome many existing barriers. This success has resulted in improved knowledge on pharmacokinetics, safety, and efficacy of therapeutics in children. To date, research in pregnant women has not been characterized by similar success. Wide gaps in knowledge remain despite the common use of therapeutics in pregnancy. Given the similar barriers to drug research and development in pediatric and pregnant populations, the route toward success in children may serve as a model for the advancement of drug development and appropriate drug administration in pregnant women. Copyright © 2015 Elsevier Inc. All rights reserved.

Barriers to the adoption of low carbon production: A multiple-case study of Chinese industrial firms

International Nuclear Information System (INIS)

Liu, Yong

2014-01-01

This study employs a multiple-case study method, identifies barriers to the adoption of low carbon production, and categorizes these barriers into four domains: structural, regulatory, cultural, and contextual. The two most frequently mentioned barriers were “lack of financial incentives to stimulate low carbon innovation” and “lack of a common definition of low carbon production”. The two least frequently mentioned barriers were “silos exist between planning and production” and “operational staff are often physically separated from planning staff, which isolates them from planning decisions”. Furthermore, contextual barriers were significantly related to structural and regulatory barriers, while regulatory barriers were significantly related to structural barriers. Larger firms tend to have a more structured organization and lower perceptions of the employment term barrier. However, larger structured organizations have been affected by a long history of a planning-oriented economy and hence tend to have inflexible hierarchical systems. In contrast, small firms have hierarchical systems with less effect on low carbon production than those of large enterprises. Another interesting trend is the direct size effect on cultural barriers, which is evident in a culture of risk aversion, as well as the lack of low carbon technology and the existence of silos between planning and production. - Highlights: • Barriers were categorized as structural, regulatory, cultural and contextual. • Contextual barriers were significantly related to structural and regulatory barriers. • Regulatory barriers were significantly related to structural barriers. • Firm size directly affected firm hierarchical systems and cultural barriers

Breaking Barriers to Bike Share: Insights from Residents of Traditionally Underserved Neighborhoods

Science.gov (United States)

2017-06-01

Evidence has shown that higher income and white populations are overrepresented in both access to and use of bike share. Efforts to overcome underserved communities barriers to access and use of bike share have been initiated in a number of cities...