The prevalence of asthma risk and contributing factors in underserved Vietnamese children in Orange County, CA.

PubMed

Nguyen, Tan; Kilgore, David; Morphew, Tricia; Tran, Jacqueline; Berg, Jill; Galant, Stanley

2015-01-01

Vietnamese constitutes one of the fastest growing minority groups in America, with the largest concentration in Orange County (OC), CA. Yet, there are limited data on the prevalence of asthma in Vietnamese children. Our study evaluated the risk of asthma and key contributing factors among these children living in OC, CA. Five elementary schools in OC that were predominantly Vietnamese with low socioeconomic status were selected for participation. Validated surveys were sent to parents of all students ages 3-12 in these schools with materials available in English, Vietnamese and Spanish. Surveys included questions to identify the risk of asthma and related key factors. Surveys were completed by parents and returned to schools. There were 1530 participants eligible for analysis. Asthma risk was 30.4%, and of these, 22.6% had no prior diagnosis. Contributing factors to identification of those at risk were male gender (p < 0.001), preferred use of the Vietnamese language (p = 0.004), longer duration in the United States (p = 0.019), and smoker in the household (p = 0.015). The prevalence of asthma risk in our community of low socioeconomic status Vietnamese children was found to be higher than commonly appreciated. Furthermore, a considerable number of these children had not been previously diagnosed. Given the limited information in this population, our current findings of asthma risk and key contributing factors could affect health care policies that allow appropriate funding for programs dedicated to asthma care in this and other growing population.

ANALYSIS OF PARTICULATE BOUND NUTRIENTS IN URBAN STORMWATER

EPA Science Inventory

Nutrients are important players in the degradation of waterbodies because they are often the elements that limit primary productivity and, hence, are the key factors controlling eutrophication. Eutrophication causes unsightly algal blooms leading to oxygen depletion, stress on o...

In search of a general theory of species' range evolution.

PubMed

Connallon, Tim; Sgrò, Carla M

2018-06-13

Despite the pervasiveness of the world's biodiversity, no single species has a truly global distribution. In fact, most species have very restricted distributions. What limits species from expanding beyond their current geographic ranges? This has been classically treated by ecologists as an ecological problem and by evolutionary biologist as an evolutionary problem. Such a dichotomy is false-the problem of species' ranges sits firmly within the realm of evolutionary ecology. In support of this view, Polechová presents new theory that explains species' range limits with reference to two key factors central to both ecological and evolutionary theory-migration and population size. This new model sets the scene for empirical tests of range limit theory and builds the case for assisted gene flow as a key management tool for threatened species.

Improvement of CSCW Software Implementation in NPD: The CAM Mechanism for a Better Adoption by Users

ERIC Educational Resources Information Center

Restrepo, Tomas; Arbelaez, Natalia; Millet, Dominique; Gidel, Thierry

2010-01-01

Cooperation between disseminated actors is a key factor in improving new product development (NPD) performance. In the last years, numerous CSCW software applications have been introduced in the industry to support NPD with a low success rate. This is partly due to the limited insight of the organisational and human factors influencing user…

Mutations in the rpoS gene are the major limiting factor for biofilm formation in Escherichia coli serotype O157:H7 clinical isolates

USDA-ARS?s Scientific Manuscript database

Background: Biofilm formation is a complex process that is highly regulated through a battery of transcriptional regulators, small regulatory RNAs, and environmental conditions. RpoS sigma factor along with MlrA protein directly regulate the expression of the curli key regulator CsgD. In most serot...

Understanding of empty container movement: A study on a bottleneck at an off-dock depot

NASA Astrophysics Data System (ADS)

Zain, Rosmaizura Mohd; Rahman, Mohd Nizam Ab; Nopiah, Zulkifli Mohd; Saibani, Nizaroyani

2014-09-01

Port not only function as connections between marine and land transportation but also as core business areas. In a port terminal, available space is limited, but the influx of container is growing. The off-dock depot is one of the key supply chain players that hold empty containers in the inventory. Therefore, this paper aims to identify the main factors of bottlenecks or congestion that hinder the rapid movement of empty containers from the off-dock depot to the customers. Thirty interviews were conducted with individuals who are key players in the container supply chain. The data were analyzed using Atlas.ti software and the analytic hierarchy process to rank the priority factors of bottlenecks. Findings show that several pertinent factors act as barriers to the key players in the container movement in the day-to-day operations. In future studies, strategies to overcome fragmentation in the container supply chain and logistics must be determined.

The Future of Clinical Education: Opportunities and Challenges from Allied Health Deans' Perspective.

PubMed

Romig, Barbara D; Tucker, Ann W; Hewitt, Anne M; O'Sullivan Maillet, Julie

2017-01-01

There is limited information and consensus on the future of clinical education and the key factors impacting allied health (AH) clinical training. AH deans identified both opportunities and challenges impacting clinical education based on a proposed educational model. From July 2013 to March 2014, 61 deans whose institutions were 2013 members of the Association of Schools of Allied Health Professions (ASAHP) participated in a three-round Delphi survey. Agreement on the relative importance of and the ability to impact the key factors was analyzed. Impact was evaluated for three groups: individual, collective, and both individual and collective deans. AH deans' responses were summarized and refined; individual items were accepted or rerated until agreement was achieved or study conclusion. Based on the deans' ratings of importance and impact, 159 key factors within 13 clinical education categories emerged as important for the future of clinical education. Agreement was achieved on 107 opportunities and 52 challenges. The Delphi technique generated new information where little existed specific to AH deans' perspectives on AH clinical education. This research supports the Key Factors Impacting Allied Health Clinical Education conceptual model proposed earlier and provides a foundation for AH deans to evaluate opportunities and challenges impacting AH clinical education and to design action plans based on this research.

The physical and mental health of lesbian, gay male, and bisexual (LGB) older adults: the role of key health indicators and risk and protective factors.

PubMed

Fredriksen-Goldsen, Karen I; Emlet, Charles A; Kim, Hyun-Jun; Muraco, Anna; Erosheva, Elena A; Goldsen, Jayn; Hoy-Ellis, Charles P

2013-08-01

Based on resilience theory, this paper investigates the influence of key health indicators and risk and protective factors on health outcomes (including general health, disability, and depression) among lesbian, gay male, and bisexual (LGB) older adults. A cross-sectional survey was conducted with LGB older adults, aged 50 and older (N = 2,439). Logistic regressions were conducted to examine the contributions of key health indicators (access to health care and health behaviors), risk factors (lifetime victimization, internalized stigma, and sexual identity concealment), and protective factors (social support and social network size) to health outcomes, when controlling for background characteristics. The findings revealed that lifetime victimization, financial barriers to health care, obesity, and limited physical activity independently and significantly accounted for poor general health, disability, and depression among LGB older adults. Internalized stigma was also a significant predictor of disability and depression. Social support and social network size served as protective factors, decreasing the odds of poor general health, disability, and depression. Some distinct differences by gender and sexual orientation were also observed. High levels of poor general health, disability, and depression among LGB older adults are of major concern. These findings highlight the important role of key risk and protective factors, which significantly influences health outcomes among LGB older adults. Tailored interventions must be developed to address the distinct health issues facing this historically disadvantaged population.

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2013-03-01

crowded environments, stairs , ramps, and hills. The key factor that limits the ability of amputees to achieve maximum functional capabilities is falls...Method for evoking a trip response using a treadmill based perturbation during locomotion”, has been submitted to the Journal of Biomechanics o

The social context of anxiety and depression: exploring the role of anxiety and depression in the lives of Australian adults with epilepsy.

PubMed

Peterson, C L; Walker, C; Shears, G

2014-05-01

To examine key determinants of anxiety and depression in a community sample of people with epilepsy. Data were analyzed from the 2010 Australian Epilepsy Longitudinal Survey, examining living with epilepsy in Australia. The HADS was analyzed, and Pearson correlations and block recursive regression were undertaken to identify key associations between anxiety, depression, and a range of variables and to identify key determinants of anxiety and depression. Key factors to influence anxiety were social aspects of stigma, effectiveness of seizure control, whether in employment, and the number of different epilepsy drugs. Determinants for depression were social aspects of stigma, whether in employment, and the effectiveness of seizure control. Stigma was also found to be an important mediating variable for employment, control, and the number of drugs. Understanding the mechanisms involved in anxiety and depression in a community sample of people with epilepsy requires the inclusion of opportunities for paid employment and the effects of psychosocial factors such as stigma. Without this fuller social context, there are limitations on understanding factors that influence anxiety and depression and how to deal with the outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

Application of a framework for extrapolating chemical effects across species in pathways controlled by estrogen receptor-á

EPA Science Inventory

Cross-species extrapolation of toxicity data from limited surrogate test organisms to all wildlife with potential of chemical exposure remains a key challenge in ecological risk assessment. A number of factors affect extrapolation, including the chemical exposure, pharmacokinetic...

Structural and Psycho-Social Limits to Climate Change Adaptation in the Great Barrier Reef Region

PubMed Central

Evans, Louisa S.; Hicks, Christina C.; Adger, W. Neil; Barnett, Jon; Perry, Allison L.; Fidelman, Pedro; Tobin, Renae

2016-01-01

Adaptation, as a strategy to respond to climate change, has limits: there are conditions under which adaptation strategies fail to alleviate impacts from climate change. Research has primarily focused on identifying absolute bio-physical limits. This paper contributes empirical insight to an emerging literature on the social limits to adaptation. Such limits arise from the ways in which societies perceive, experience and respond to climate change. Using qualitative data from multi-stakeholder workshops and key-informant interviews with representatives of the fisheries and tourism sectors of the Great Barrier Reef region, we identify psycho-social and structural limits associated with key adaptation strategies, and examine how these are perceived as more or less absolute across levels of organisation. We find that actors experience social limits to adaptation when: i) the effort of pursuing a strategy exceeds the benefits of desired adaptation outcomes; ii) the particular strategy does not address the actual source of vulnerability, and; iii) the benefits derived from adaptation are undermined by external factors. We also find that social limits are not necessarily more absolute at higher levels of organisation: respondents perceived considerable opportunities to address some psycho-social limits at the national-international interface, while they considered some social limits at the local and regional levels to be effectively absolute. PMID:26960200

Structural and Psycho-Social Limits to Climate Change Adaptation in the Great Barrier Reef Region.

PubMed

Evans, Louisa S; Hicks, Christina C; Adger, W Neil; Barnett, Jon; Perry, Allison L; Fidelman, Pedro; Tobin, Renae

2016-01-01

Adaptation, as a strategy to respond to climate change, has limits: there are conditions under which adaptation strategies fail to alleviate impacts from climate change. Research has primarily focused on identifying absolute bio-physical limits. This paper contributes empirical insight to an emerging literature on the social limits to adaptation. Such limits arise from the ways in which societies perceive, experience and respond to climate change. Using qualitative data from multi-stakeholder workshops and key-informant interviews with representatives of the fisheries and tourism sectors of the Great Barrier Reef region, we identify psycho-social and structural limits associated with key adaptation strategies, and examine how these are perceived as more or less absolute across levels of organisation. We find that actors experience social limits to adaptation when: i) the effort of pursuing a strategy exceeds the benefits of desired adaptation outcomes; ii) the particular strategy does not address the actual source of vulnerability, and; iii) the benefits derived from adaptation are undermined by external factors. We also find that social limits are not necessarily more absolute at higher levels of organisation: respondents perceived considerable opportunities to address some psycho-social limits at the national-international interface, while they considered some social limits at the local and regional levels to be effectively absolute.

What is limiting more flexible fire management—public or agency pressure?

Treesearch

Toddi A. Steelman; Sarah M. McCaffrey

2011-01-01

Conventional wisdom within American federal fire management agencies suggests that external influence such as community or political pressure for aggressive suppression are key factors circumscribing the ability to execute less aggressive fire management strategies. Thus, a better understanding of external constraints on fire management options is essential. This...

Realizing the Potential of Ecosystem Services: A Framework for Relating Ecological Changes to Economic Benefits

EPA Science Inventory

An analysis framework to link ecological change to economic benefits for multiple stakeholders requires several key components. First, since we aim to support policy decisions, the framework should link a factor that can be controlled or influenced by policy (discharge limit, ca...

Crystal growth of device quality GaAs in space

NASA Technical Reports Server (NTRS)

Gatos, H. C.; Lagowski, J.

1979-01-01

The optimization of space processing of GaAs is described. The detailed compositional, structural, and electronic characterization of GaAs on a macro- and microscale and the relationships between growth parameters and the properties of GaAs are among the factors discussed. The key parameters limiting device performance are assessed.

The Scientific Basis of Uncertainty Factors Used in Setting Occupational Exposure Limits.

PubMed

Dankovic, D A; Naumann, B D; Maier, A; Dourson, M L; Levy, L S

2015-01-01

The uncertainty factor concept is integrated into health risk assessments for all aspects of public health practice, including by most organizations that derive occupational exposure limits. The use of uncertainty factors is predicated on the assumption that a sufficient reduction in exposure from those at the boundary for the onset of adverse effects will yield a safe exposure level for at least the great majority of the exposed population, including vulnerable subgroups. There are differences in the application of the uncertainty factor approach among groups that conduct occupational assessments; however, there are common areas of uncertainty which are considered by all or nearly all occupational exposure limit-setting organizations. Five key uncertainties that are often examined include interspecies variability in response when extrapolating from animal studies to humans, response variability in humans, uncertainty in estimating a no-effect level from a dose where effects were observed, extrapolation from shorter duration studies to a full life-time exposure, and other insufficiencies in the overall health effects database indicating that the most sensitive adverse effect may not have been evaluated. In addition, a modifying factor is used by some organizations to account for other remaining uncertainties-typically related to exposure scenarios or accounting for the interplay among the five areas noted above. Consideration of uncertainties in occupational exposure limit derivation is a systematic process whereby the factors applied are not arbitrary, although they are mathematically imprecise. As the scientific basis for uncertainty factor application has improved, default uncertainty factors are now used only in the absence of chemical-specific data, and the trend is to replace them with chemical-specific adjustment factors whenever possible. The increased application of scientific data in the development of uncertainty factors for individual chemicals also has the benefit of increasing the transparency of occupational exposure limit derivation. Improved characterization of the scientific basis for uncertainty factors has led to increasing rigor and transparency in their application as part of the overall occupational exposure limit derivation process.

[Assessment of the potential for urban facade greening in Xinjiekou District, Nanjing, China.

PubMed

Shi, Bao Gang; Yin, Hai Wei; Kong, Fan Hua

2018-05-01

Green facade is an important strategy to improve the urban eco-environment and reduce the negative effects of human activities in central districts of cities which are land-scarce and lack green spaces. We first summarized the limiting factors for the construction of green facades locally and internationally. Then, we used the Xinjiekou District of Nanjing City in China as a case study area, and selected the wind environment, solar environment, and physical build environment that might impact the potential development of green facades as key factors to quantitatively analyze singlely by geographic information systems (GIS) and computational fluid dynamics (CFD). Finally, the potential area to develop green facades was assessed through a multi-factor overlay analysis. The results showed that 17726 m 2 of wall spaces in the Xinjiekou District had a high potential for facade greening, accounting for 30.8% of all exterior wall space under a height of 12 m and 17.3% of the entire study area. Sunlight was a key limiting factor in determining whether a green facade should be developed. Irrigation was identified as another important factor that might strongly affect the growth of vertical vegetation in urban environment. The spatial distribution of walls suitable for facade greening was uneven, with an "inner-high and south-high" spatial pattern. Our results would help to guide the design and development of green facades in Xinjiekou, and also provide a reference for planning and utilizing green wall space projects in other built and dense urban areas.

Beating the limits with initial correlations

NASA Astrophysics Data System (ADS)

Basilewitsch, Daniel; Schmidt, Rebecca; Sugny, Dominique; Maniscalco, Sabrina; Koch, Christiane P.

2017-11-01

Fast and reliable reset of a qubit is a key prerequisite for any quantum technology. For real world open quantum systems undergoing non-Markovian dynamics, reset implies not only purification, but in particular erasure of initial correlations between qubit and environment. Here, we derive optimal reset protocols using a combination of geometric and numerical control theory. For factorizing initial states, we find a lower limit for the entropy reduction of the qubit as well as a speed limit. The time-optimal solution is determined by the maximum coupling strength. Initial correlations, remarkably, allow for faster reset and smaller errors. Entanglement is not necessary.

Liposome production by microfluidics: potential and limiting factors

PubMed Central

Carugo, Dario; Bottaro, Elisabetta; Owen, Joshua; Stride, Eleanor; Nastruzzi, Claudio

2016-01-01

This paper provides an analysis of microfluidic techniques for the production of nanoscale lipid-based vesicular systems. In particular we focus on the key issues associated with the microfluidic production of liposomes. These include, but are not limited to, the role of lipid formulation, lipid concentration, residual amount of solvent, production method (including microchannel architecture), and drug loading in determining liposome characteristics. Furthermore, we propose microfluidic architectures for the mass production of liposomes with a view to potential industrial translation of this technology. PMID:27194474

Liposome production by microfluidics: potential and limiting factors.

PubMed

Carugo, Dario; Bottaro, Elisabetta; Owen, Joshua; Stride, Eleanor; Nastruzzi, Claudio

2016-05-19

This paper provides an analysis of microfluidic techniques for the production of nanoscale lipid-based vesicular systems. In particular we focus on the key issues associated with the microfluidic production of liposomes. These include, but are not limited to, the role of lipid formulation, lipid concentration, residual amount of solvent, production method (including microchannel architecture), and drug loading in determining liposome characteristics. Furthermore, we propose microfluidic architectures for the mass production of liposomes with a view to potential industrial translation of this technology.

Understanding Mathematics: Some Key Factors

ERIC Educational Resources Information Center

Ali, Asma Amanat; Reid, Norman

2012-01-01

Mathematics is well known as a subject area where there can be problems in terms of understanding as well as retaining positive attitudes. In a large study involving 813 school students (ages approximately 10-12) drawn from two different school systems in Pakistan, the effect of limited working memory capacity on performance in mathematics was…

Improved method for extraction of castor seed for toxin determination

USDA-ARS?s Scientific Manuscript database

The effort to identify castor seeds with low ricin content is considered to be a key to increasing cultivation of the castor plant for industrial applications. The procedure used to obtain soluble protein from the seed is a limiting factor for screening large numbers of seeds. Usually, the seed is...

Fire environmental test chamber: its design and development

Treesearch

Clifford J. Auvil

1973-01-01

The Fire Environmental Test Chamber at the Forest Fire Laboratory, Riverside, California, can duplicate under controlled conditions the key factors that affect the flammability of wildland fuels. Within certain limits, it can produce air flow, solar radiation, temperatures, and relative humidity. First developed in 1962, the test chamber has since then undergoneseveral...

A Trillion-Dollar Question: What Predicts Student Loan Delinquencies?

ERIC Educational Resources Information Center

Mezza, Alvaro; Sommer, Kamila

2016-01-01

The recent significant increase in student loan delinquencies has generated interest in understanding the key factors predicting the non-performance of these loans. However, despite the large size of the student loan market, existing analyses have been limited by lack of data. This paper studies predictors of student loan delinquencies using a…

Ubiquitous Learning: Determinants Impacting Learners' Satisfaction and Performance with Smartphones

ERIC Educational Resources Information Center

Jung, Hee-Jung

2014-01-01

Although the concept of ubiquitous technologies has been introduced to many parts of society, there have been limited applications, and little is known about learners' behavior toward ubiquitous technologies, particularly in the context of English learning. This study considers a sample of Korean students to identify the key factors that influence…

Parental Characteristics and Resiliency in Identification Rates for Special Education

ERIC Educational Resources Information Center

Anderson, Jeffrey A.; Howland, Allison A.; McCoach, D. Betsy

2015-01-01

Even with increased risks, many children demonstrate resiliency and avoid being labeled for special education; however, research on risk and resilience has been problematic because of inadequate statistical models, limitations of available data, and the exclusion of key protective factors. This study used a national sample to examine the influence…

How to Make Diagnosis Related Groups Payment More Feasible in Developing Countries- A Case Study in Shanghai, China

PubMed Central

WANG, Zhaoxin; LIU, Rui; LI, Ping; JIANG, Chenghua; HAO, Mo

2014-01-01

Abstract Background Given limited health sources, how to make DRGs (Diagnosis Related Groups) more feasible is a big question in developing countries. This study contributes to the debate on how to bridge the pay-for-service and DRGs during the transitional period of payment reform. Methods From 2008 to 2012, 20740 patients with cirrhosis or duodenal ulcer disease were chosen as sample. Using multiple linear regression analysis, the interrelationships between the total medical expenses of the inpatients, and age, gender of the inpatients, length of stay (LOS), region and economic level of the hospitals were examined. Results The main findings were 1) length of stay (LOS) and the economic level of treatment location had a statistically significant impact on patients with cirrhosis or duodenal ulcer disease. Meanwhile gender is not a significant factor for both of them. 2) Under the premise of limited resources, developing countries should first narrow down to screen for common and frequently occurring diseases, then study the key factors which affect the treatment cost of the diseases. Conclusion Based on picking out common diseases and their key factors, Simplification of the DRGs setting process will greatly increase the efficiency of implementing DRGs in the developing world. PMID:26060758

Effect of acculturation on variations in having a usual source of care among Asian Americans and non-Hispanic whites in California.

PubMed

Chang, Eva; Chan, Kitty S; Han, Hae-Ra

2015-02-01

We examined variations in having a usual source of care (USC) among non-Hispanic White and Asian American adults in California. Data were from the 2005 and 2009 California Health Interview Survey. Using a modified Anderson model, we used multiple logistic regression to compare odds of having a USC between non-Hispanic White (n=38554) and Asian American adults (n=7566) and to examine associations with acculturation factors (English proficiency, length of residence, residence in a racially concordant neighborhood) and key enabling (employment, income, insurance) and predisposing (education) factors. Race-related disparities between Asian Americans and non-Hispanic Whites in having a USC were no longer significant after accounting for acculturation factors. Limited English proficiency and short time in the United States (<5 years) were significantly associated with not having a USC for both races. Increasing levels of education and insurance were not associated with better access among Asian Americans. Key differences exist in how Asian American and non-Hispanic White adults access care. Acculturation factors are key drivers of disparities and should be included in access-to-care models with Asians. Insurance and education are differentially significant for Asian Americans and non-Hispanic Whites.

Effect of Acculturation on Variations in Having a Usual Source of Care Among Asian Americans and Non-Hispanic Whites in California

PubMed Central

Han, Hae-Ra

2015-01-01

Objectives. We examined variations in having a usual source of care (USC) among non-Hispanic White and Asian American adults in California. Methods. Data were from the 2005 and 2009 California Health Interview Survey. Using a modified Anderson model, we used multiple logistic regression to compare odds of having a USC between non-Hispanic White (n = 38 554) and Asian American adults (n = 7566) and to examine associations with acculturation factors (English proficiency, length of residence, residence in a racially concordant neighborhood) and key enabling (employment, income, insurance) and predisposing (education) factors. Results. Race-related disparities between Asian Americans and non-Hispanic Whites in having a USC were no longer significant after accounting for acculturation factors. Limited English proficiency and short time in the United States (< 5 years) were significantly associated with not having a USC for both races. Increasing levels of education and insurance were not associated with better access among Asian Americans. Conclusions. Key differences exist in how Asian American and non-Hispanic White adults access care. Acculturation factors are key drivers of disparities and should be included in access-to-care models with Asians. Insurance and education are differentially significant for Asian Americans and non-Hispanic Whites. PMID:25033147

Security analysis and improvements of two-factor mutual authentication with key agreement in wireless sensor networks.

PubMed

Kim, Jiye; Lee, Donghoon; Jeon, Woongryul; Lee, Youngsook; Won, Dongho

2014-04-09

User authentication and key management are two important security issues in WSNs (Wireless Sensor Networks). In WSNs, for some applications, the user needs to obtain real-time data directly from sensors and several user authentication schemes have been recently proposed for this case. We found that a two-factor mutual authentication scheme with key agreement in WSNs is vulnerable to gateway node bypassing attacks and user impersonation attacks using secret data stored in sensor nodes or an attacker's own smart card. In this paper, we propose an improved scheme to overcome these security weaknesses by storing secret data in unique ciphertext form in each node. In addition, our proposed scheme should provide not only security, but also efficiency since sensors in a WSN operate with resource constraints such as limited power, computation, and storage space. Therefore, we also analyze the performance of the proposed scheme by comparing its computation and communication costs with those of other schemes.

Security Analysis and Improvements of Two-Factor Mutual Authentication with Key Agreement in Wireless Sensor Networks

PubMed Central

Kim, Jiye; Lee, Donghoon; Jeon, Woongryul; Lee, Youngsook; Won, Dongho

2014-01-01

User authentication and key management are two important security issues in WSNs (Wireless Sensor Networks). In WSNs, for some applications, the user needs to obtain real-time data directly from sensors and several user authentication schemes have been recently proposed for this case. We found that a two-factor mutual authentication scheme with key agreement in WSNs is vulnerable to gateway node bypassing attacks and user impersonation attacks using secret data stored in sensor nodes or an attacker's own smart card. In this paper, we propose an improved scheme to overcome these security weaknesses by storing secret data in unique ciphertext form in each node. In addition, our proposed scheme should provide not only security, but also efficiency since sensors in a WSN operate with resource constraints such as limited power, computation, and storage space. Therefore, we also analyze the performance of the proposed scheme by comparing its computation and communication costs with those of other schemes. PMID:24721764

New technology planning and approval: critical factors for success.

PubMed

Haselkorn, Ateret; Rosenstein, Alan H; Rao, Anil K; Van Zuiden, Michele; Coye, Molly J

2007-01-01

The steady evolution of technology, with the associated increased costs, is a major factor affecting health care delivery. In the face of limited capital resources, it is important for hospitals to integrate technology management with the strategic plan, mission, and resource availability of the organization. Experiences in technology management have shown that having a well-organized, consistent approach to technology planning, assessment, committee membership, approval, evaluation, implementation, and monitoring are key factors necessary to ensure a successful program. We examined the results of a survey that assessed the structure, processes, and cultural support behind hospital committees for new technology planning and approval.

Unraveling the Slut Narrative: Gender Constraints on Adolescent Girls' Sexual Decision-Making

ERIC Educational Resources Information Center

Summit, Aleza K.; Kalmuss, Debra; DeAtley, Jenifer; Levack, Andrew

2016-01-01

Limited research exists on the slut labeling process, a key means of enforcing rules around appropriate female sexuality. This study explores that process through qualitative interviews with 44 adolescent girls in Travis County, Texas. Labeling girls as sluts or hos was pervasive and was based on a number of factors beyond sexual behavior,…

Unorganized Cognitive Structures of Illiterate as the Key Factor in Rural E-Learning Design

ERIC Educational Resources Information Center

Katre, Dinesh S.

2006-01-01

Cognitive Structures and Linguistic Sequential Memory or Memory of Serial Order are not very well developed among illiterate people contrary to educated people. It affects the comprehension of abstract ideas and the usability of the system. Therefore the cognitive limitations of illiterate must be considered for instructional design and user…

Gender Representations in U.S. Ed.D. Dissertations: A Feminist Content Analysis

ERIC Educational Resources Information Center

Nelli, Debora Kay

2014-01-01

Educational access, achievement and opportunity for students and educators in U.S. educational institutions is influenced and often limited by gender. Although the U.S. Glass Ceiling Commission reports that the gender equity values, beliefs and commitments of institutional leaders are a key factor in reducing institutional gender inequities (U.S.…

Keys to the Adoption and Use of Voice Recognition Technology in Organizations.

ERIC Educational Resources Information Center

Goette, Tanya

2000-01-01

Presents results from a field study of individuals with disabilities who used voice recognition technology (VRT). Results indicated that task-technology fit, training, the environment, and disability limitations were the differentiating items, and that using VRT for a trial period may be the major factor in successful adoption of the technology.…

Need for "conflict version" of primary surgery: war surgery in the era of low-intensity conflicts.

PubMed

Morikawa, Masahiro J

2006-01-01

The conventional wars between nations have widely been replaced by low-intensity conflicts within nations today, resulting in different patterns of injuries and practice of surgical care. A blurred front line, protracted durations of violence, indiscriminant fighting, and the emergence of specific surgical problems characterize low-intensity conflicts. In protracted conflicts with limited resources, surgical outcomes depend on many factors other than surgical skills, such as social/cultural values and economical feasibility. This paper examines how the characteristics of current conflicts affect surgical practice and will address key issues to evolve care to adapt to these changes. Key issues are (1) need for comprehensive surgical skills, (2) importance of improving local capacities, (3) long-term impact of trauma, and (4) limited access to information required to improve surgical skills.

Mobile-PKI Service Model for Ubiquitous Environment

NASA Astrophysics Data System (ADS)

Jeun, Inkyung; Chun, Kilsoo

One of the most important things in PKI(Public Key Infrastructure) is the private key management issue. The private key must be deal with safely for secure PKI service. Even though PKI service is usually used for identification and authentication of user in e-commerce, PKI service has many inconvenient factors. Especially, the fact that storage media of private key for PKI service is limited to PC hard disk drive or smart card users must always carry, gives an inconvenience to user and is not suitable in ubiquitous network. This paper suggests the digital signature service using a mobile phone(m-PKI service) which is suitable in future network. A mobile phone is the most widely used for personal communication means and has a characteristic of high movability. We can use the PKI service anytime and anywhere using m-PKI.

Environmental Influences on Physical Activity among Rural Adults in Montana, United States: Views from Built Environment Audits, Resident Focus Groups, and Key Informant Interviews.

PubMed

Lo, Brian K; Morgan, Emily H; Folta, Sara C; Graham, Meredith L; Paul, Lynn C; Nelson, Miriam E; Jew, Nicolette V; Moffat, Laurel F; Seguin, Rebecca A

2017-10-04

Rural populations in the United States have lower physical activity levels and are at a higher risk of being overweight and suffering from obesity than their urban counterparts. This paper aimed to understand the environmental factors that influence physical activity among rural adults in Montana. Eight built environment audits, 15 resident focus groups, and 24 key informant interviews were conducted between August and December 2014. Themes were triangulated and summarized into five categories of environmental factors: built, social, organizational, policy, and natural environments. Although the existence of active living features was documented by environmental audits, residents and key informants agreed that additional indoor recreation facilities and more well-maintained and conveniently located options were needed. Residents and key informants also agreed on the importance of age-specific, well-promoted, and structured physical activity programs, offered in socially supportive environments, as facilitators to physical activity. Key informants, however, noted that funding constraints and limited political will were barriers to developing these opportunities. Since building new recreational facilities and structures to support active transportation pose resource challenges, especially for rural communities, our results suggest that enhancing existing features, making small improvements, and involving stakeholders in the city planning process would be more fruitful to build momentum towards larger changes.

Improving the Representation of Land in Climate Models by Application of EOS Observations

NASA Technical Reports Server (NTRS)

2004-01-01

The PI's IDS current and previous investigation has focused on the applications of the land data toward the improvement of climate models. The previous IDS research identified the key factors limiting the accuracy of climate models to be the representation of albedos, land cover, fraction of landscape covered by vegetation, roughness lengths, surface skin temperature and canopy properties such as leaf area index (LAI) and average stomatal conductance. Therefore, we assembled a team uniquely situated to focus on these key variables and incorporate the remotely sensed measures of these variables into the next generation of climate models.

Employees' Motivation for SPI: Case Study in a Small Finnish Software Company

NASA Astrophysics Data System (ADS)

Valtanen, Anu; Sihvonen, Hanna-Miina

In small software companies the resources available for SPI are often limited. With limited resources, the motivation of the employees becomes one of the key factors for SPI. In this article, the motivational factors affecting a small company's SPI efforts are discussed. In the research, we carried out interviews and a survey in a small Finnish software company considering the motivation towards SPI. The results are presented here and compared with earlier motivation research. There were differences revealed while comparing the motivating factors of smaller companies to those of larger ones. In large companies the focus seems to be on the business related motivators and in small ones the motivators related to comfortability of work are emphasized. Motivation survey and the interviews proved to be useful tools in planning the future SPI strategy. A lot of valuable information was discovered for planning and implementing the next steps of SPI.

Beyond the limitations of best practices: how logic analysis helped reinterpret dual diagnosis guidelines.

PubMed

Brousselle, Astrid; Lamothe, Lise; Mercier, Céline; Perreault, Michel

2007-02-01

The co-occurrence of mental health and substance use disorders is becoming increasingly recognized as a single problem, and professionals recognize that both should be addressed at the same time. Medical best practices recommend integrated treatment. However, criticisms have arisen, particularly concerning the difficulty of implementing integrated teams in specific health-care contexts and the appropriateness of the proposed model for certain populations. Using logic analysis, we identify the key clinical and organizational factors that contribute to successful implementation. Building on both the professional and organizational literatures on integrated services, we propose a conceptual model that makes it possible to analyze integration processes and places integrated treatment within an interpretative framework. Using this model, it becomes possible to identify key factors necessary to support service integration, and suggest new models of practice adapted to particular contexts.

Spatial Variability of Cyanobacteria and Heterotrophic Bacteria in Lake Taihu (China).

PubMed

Qian, Haifeng; Lu, Tao; Song, Hao; Lavoie, Michel; Xu, Jiahui; Fan, Xiaoji; Pan, Xiangliang

2017-09-01

Cyanobacterial blooms frequently occur in Lake Taihu (China), but the intertwined relationships between biotic and abiotic factors modulating the frequency and duration of the blooms remain enigmatic. To better understand the relationships between the key abiotic and biotic factors and cyanobacterial blooms, we measured the abundance and diversity of prokaryotic organisms by high-throughput sequencing, the abundance of key genes involved in microcystin production and nitrogen fixation or loss as well as several physicochemical parameters at several stations in Lake Taihu during a cyanobacterial bloom of Microcystis sp.. Measurements of the copy number of denitrification-related genes and 16S rRNA analyses show that denitrification potential and denitrifying bacteria abundance increased in concert with non-diazotrophic cyanobacteria (Microcystis sp.), suggesting limited competition between cyanobacteria and heterotrophic denitrifiers for nutrients, although potential bacteria-mediated N loss may hamper Microcystis growth. The present study provides insight into the importance of different abiotic and biotic factors in controlling cyanobacteria and heterotrophic bacteria spatial variability in Lake Taihu.

Structural design/margin assessment

NASA Technical Reports Server (NTRS)

Ryan, R. S.

1993-01-01

Determining structural design inputs and the structural margins following design completion is one of the major activities in space exploration. The end result is a statement of these margins as stability, safety factors on ultimate and yield stresses, fracture limits (fracture control), fatigue lifetime, reuse criteria, operational criteria and procedures, stability factors, deflections, clearance, handling criteria, etc. The process is normally called a load cycle and is time consuming, very complex, and involves much more than structures. The key to successful structural design is the proper implementation of the process. It depends on many factors: leadership and management of the process, adequate analysis and testing tools, data basing, communications, people skills, and training. This process and the various factors involved are discussed.

An Exploration of the Alienation Experienced by African American Parents from Their Children's Educational Environment

ERIC Educational Resources Information Center

Brandon, Regina R.; Higgins, Kyle; Pierce, Tom; Tandy, Richard; Sileo, Nancy

2010-01-01

Current research suggests that parents are a key component to the school success of their children. However, in today's world, parents often work long hours, have more than one job, and participate in multiple responsibilities that may limit their participation. Because of the variety of factors that impinge on parents, educators often criticize…

Sustaining and Scaling Up Pedagogic Innovation in Sub-Saharan Africa: Grounded Insights for Teacher Professional Development

ERIC Educational Resources Information Center

Hassler, Bjoern; Hennessy, Sara; Hofmann, Riikka

2018-01-01

Developing sustainable and scalable educational initiatives is a key challenge in low-income countries where donor-funded short-term projects are limited by both contextual factors and programme design. In this commentary we examine some of the issues related to in-service teacher development in the context of sub-Saharan Africa, grounded…

Estimating the Occurrence of Child Maltreatment and Risk-Factor Effects: Benefits of a Mixed-Design Strategy in Epidemiologic Research.

ERIC Educational Resources Information Center

Bertolli, Jeanne; And Others

1995-01-01

This article discusses methodologic limitations of four observational study designs (ecologic, case-control, cross-sectional, and cohort) that dominate the child abuse and neglect literature and identifies key features of an "ideal" study of child maltreatment. It proposes a new mixed-design strategy, which improves ability to identify child…

Relationship of Social Network to Protective Factors in Suicide and Alcohol Use Disorder Intervention for Rural Yup’ik Alaska Native Youth

PubMed Central

Philip, Jacques; Ford, Tara; Henry, David; Rasmus, Stacy; Allen, James

2015-01-01

Suicide and alcohol use disorders are significant Alaska Native health disparities, yet there is limited understanding of protection and no studies of social network factors in protection in this or other populations. The Qungasvik intervention enhances protective factors from suicide and alcohol use disorders through activities grounded in Yup’ik cultural practices and values. Identification of social network factors associated with protection within the cultural context of these tight, close knit, and high density rural Yup’ik Alaska Native communities in southwest Alaska can help identify effective prevention strategies for suicide and alcohol use disorder risk. Using data from ego-centered social network and protective factors from suicide and alcohol use disorders surveys with 50 Yup’ik adolescents, we provide descriptive data on structural and network composition variables, identify key network variables that explain major proportions of the variance in a four principal component structure of these network variables, and demonstrate the utility of these key network variables as predictors of family and community protective factors from suicide and alcohol use disorder risk. Connections to adults and connections to elders, but not peer connections, emerged as predictors of family and community level protection, suggesting these network factors as important intervention targets for intervention. PMID:27110094

Accurate expressions for solar cell fill factors including series and shunt resistances

NASA Astrophysics Data System (ADS)

Green, Martin A.

2016-02-01

Together with open-circuit voltage and short-circuit current, fill factor is a key solar cell parameter. In their classic paper on limiting efficiency, Shockley and Queisser first investigated this factor's analytical properties showing, for ideal cells, it could be expressed implicitly in terms of the maximum power point voltage. Subsequently, fill factors usually have been calculated iteratively from such implicit expressions or from analytical approximations. In the absence of detrimental series and shunt resistances, analytical fill factor expressions have recently been published in terms of the Lambert W function available in most mathematical computing software. Using a recently identified perturbative relationship, exact expressions in terms of this function are derived in technically interesting cases when both series and shunt resistances are present but have limited impact, allowing a better understanding of their effect individually and in combination. Approximate expressions for arbitrary shunt and series resistances are then deduced, which are significantly more accurate than any previously published. A method based on the insights developed is also reported for deducing one-diode fits to experimental data.

Biogeochemical provinces in the global ocean based on phytoplankton growth limitation

NASA Astrophysics Data System (ADS)

Hashioka, T.; Hirata, T.; Aita, M. N.; Chiba, S.

2016-02-01

The biogeochemical province is one of the useful concepts for the comprehensive understanding of regional differences of the marine ecosystem. Various biogeochemical provinces for lower-trophic level ecosystem have been proposed using a similarity-based classification of seasonal variations of chl-a concentration typified by Longhurst 1995 and 2006. Such categorizations well capture the regional differences of seasonality as "total phytoplankton". However, background biogeochemical mechanism to characterize the province boundary is not clear. Namely, the dominant phytoplankton group is different among regions and seasons, and their physiological characteristics are significantly different among groups. Recently some pieces of new biogeochemical information are available. One is an estimation of phytoplankton community structure from satellite observation, and it makes clear the key phytoplankton type in each region. Another is an estimation of limitation factors for phytoplankton growth (e.g., nutrients, temperature, light) in each region from modeling studies. In this study, we propose new biogeochemical provinces as a combination between the dominance of phytoplankton (i.e., diatoms, nano-, pico-phytoplankton or coexistence of two/three types) and their growth limitation factors (particularly we focused on nutrient limitation; N, P, Si or Fe). In this combination, we classified the global ocean into 23 biogeochemical provinces. The result suggests that even if the same type of phytoplankton dominates, the background mechanism could be different among regions. On the contrary, even if the regions geographically separate, the background mechanism could be similar among regions. This is important to understand that region/boundary does respond to environmental change. This biogeochemical province is useful for identification of key areas for future observation.

Museum specimens reveal loss of pollen host plants as key factor driving wild bee decline in The Netherlands.

PubMed

Scheper, Jeroen; Reemer, Menno; van Kats, Ruud; Ozinga, Wim A; van der Linden, Giel T J; Schaminée, Joop H J; Siepel, Henk; Kleijn, David

2014-12-09

Evidence for declining populations of both wild and managed bees has raised concern about a potential global pollination crisis. Strategies to mitigate bee loss generally aim to enhance floral resources. However, we do not really know whether loss of preferred floral resources is the key driver of bee decline because accurate assessment of host plant preferences is difficult, particularly for species that have become rare. Here we examine whether population trends of wild bees in The Netherlands can be explained by trends in host plants, and how this relates to other factors such as climate change. We determined host plant preference of bee species using pollen loads on specimens in entomological collections that were collected before the onset of their decline, and used atlas data to quantify population trends of bee species and their host plants. We show that decline of preferred host plant species was one of two main factors associated with bee decline. Bee body size, the other main factor, was negatively related to population trend, which, because larger bee species have larger pollen requirements than smaller species, may also point toward food limitation as a key factor driving wild bee loss. Diet breadth and other potential factors such as length of flight period or climate change sensitivity were not important in explaining twentieth century bee population trends. These results highlight the species-specific nature of wild bee decline and indicate that mitigation strategies will only be effective if they target the specific host plants of declining species.

Museum specimens reveal loss of pollen host plants as key factor driving wild bee decline in The Netherlands

PubMed Central

Scheper, Jeroen; Reemer, Menno; van Kats, Ruud; Ozinga, Wim A.; van der Linden, Giel T. J.; Schaminée, Joop H. J.; Siepel, Henk; Kleijn, David

2014-01-01

Evidence for declining populations of both wild and managed bees has raised concern about a potential global pollination crisis. Strategies to mitigate bee loss generally aim to enhance floral resources. However, we do not really know whether loss of preferred floral resources is the key driver of bee decline because accurate assessment of host plant preferences is difficult, particularly for species that have become rare. Here we examine whether population trends of wild bees in The Netherlands can be explained by trends in host plants, and how this relates to other factors such as climate change. We determined host plant preference of bee species using pollen loads on specimens in entomological collections that were collected before the onset of their decline, and used atlas data to quantify population trends of bee species and their host plants. We show that decline of preferred host plant species was one of two main factors associated with bee decline. Bee body size, the other main factor, was negatively related to population trend, which, because larger bee species have larger pollen requirements than smaller species, may also point toward food limitation as a key factor driving wild bee loss. Diet breadth and other potential factors such as length of flight period or climate change sensitivity were not important in explaining twentieth century bee population trends. These results highlight the species-specific nature of wild bee decline and indicate that mitigation strategies will only be effective if they target the specific host plants of declining species. PMID:25422416

Perceived key injury risk factors in World Cup alpine ski racing—an explorative qualitative study with expert stakeholders

PubMed Central

Spörri, Jörg; Kröll, Josef; Amesberger, Günter; Blake, Ollie M; Müller, Erich

2012-01-01

Background There is limited knowledge about key injury risk factors in alpine ski racing, particularly for World Cup (WC) athletes. Objective This study was undertaken to compile and explore perceived intrinsic and extrinsic risk factors for severe injuries in WC alpine ski racing. Methods Qualitative study. Interviews were conducted with 61 expert stakeholders of the WC ski racing community. Experts’ statements were collected, paraphrased and loaded into a database with inductively derived risk factor categories (Risk Factor Analysis). At the end of the interviews, experts were asked to name those risk factors they believed to have a high potential impact on injury risk and to rank them according to their priority of impact (Risk Factor Rating). Results In total, 32 perceived risk factors categories were derived from the interviews within the basic categories Athlete, Course, Equipment and Snow. Regarding their perceived impact on injury risk, the experts’ top five categories were: system ski, binding, plate and boot; changing snow conditions; physical aspects of the athletes; speed and course setting aspects and speed in general. Conclusions Severe injuries in WC alpine ski racing can have various causes. This study compiled a list of perceived intrinsic and extrinsic risk factors and explored those factors with the highest believed impact on injury risk. Hence, by using more detailed hypotheses derived from this explorative study, further studies should verify the plausibility of these factors as true risk factors for severe injuries in WC alpine ski racing. PMID:22872684

Performance indicators: healthcare professionals' views.

PubMed

Gu, Xiuzhu; Itoh, Kenji

2016-08-08

Purpose - The purpose of this paper is to capture factors behind professional views of indicator usefulness as a common structure for assessing healthcare performance and their important characteristics to design limited key performance indicators (PIs) for holistic hospital management. Design/methodology/approach - Two surveys were conducted using self-administered questionnaires, in which hospital manager/staff respondents were asked to rate the 52 PIs' usefulness. In total, 228 manager and 894 staff responses were collected. Findings - Eight factors were elicited from manager and staff responses as performance measures with 72 percent cumulative variance accounted for. Hospital managers and staff showed similar performance measure perceptions: high-utility acknowledgment on safety, operational efficiency and patient/employee satisfaction but relatively low-employee development concerns. Manager indicator usefulness perceptions were rather homogeneous and significantly higher than staff for almost all performance measures. Practical implications - Homogeneous manager views mean that a single key PI set for hospital management may be established regardless of hospital attributes. The following aspects may be measures that should be managed in a healthcare organization based on their key PIs: patient/employee safety, operational efficiency, financial effectiveness and patient/employee satisfaction. Originality/value - This is a pilot study on hospital management PIs in Japan. The eight-dimensional factor structure and findings about healthcare provider perceptions may be useful for healthcare management.

Key challenges for nanotechnology: Standardization of ecotoxicity testing.

PubMed

Cerrillo, Cristina; Barandika, Gotzone; Igartua, Amaya; Areitioaurtena, Olatz; Mendoza, Gemma

2017-04-03

Nanotechnology is expected to contribute to the protection of the environment, but many uncertainties exist regarding the environmental and human implications of manufactured nanomaterials (MNMs). Contradictory results have been reported for their ecotoxicity to aquatic organisms, which constitute one of the most important pathways for their entrance and transfer throughout the food web. The present review is focused on the international strategies that are laying the foundations of the ecotoxicological assessment of MNMs. Specific advice is provided on the preparation of MNM dispersions in the culture media of the organisms, which is considered a key factor to overcome the limitations in the standardization of the test methodologies.

The experience of return to work in individuals with traumatic brain injury (TBI): A qualitative study.

PubMed

Libeson, Lauren; Downing, Marina; Ross, Pamela; Ponsford, Jennie

2018-05-10

Traumatic Brain Injury (TBI) is a leading cause of disability in young people, with return to work (RTW) a major goal of recovery. This qualitative study aimed to understand the RTW experience of individuals with TBI who received comprehensive vocational rehabilitation, and to identify facilitating and limiting factors in the RTW process. Semi-structured interviews were conducted with 15 individuals (mean age = 47.33 years) approximately 4.5 years post-injury, of whom 14 had moderate to severe TBI. Twelve individuals had successfully returned to work. Thematic analysis of transcribed interviews identified three key factors affecting RTW: client, work and rehabilitation factors. Across these factors, 12 themes reported to be critical to the success or failure of the RTW programme were identified. Client themes included social support, cognitive difficulties and motivation, with RTW too early associated with unfavourable outcomes. Work themes included work modifications, employer support and financial incentives. Rehabilitation themes included the RTW programme, the role of the vocational occupational therapist and work preparation. These key factors were reported to have impacted the RTW outcome, comprising three further themes: work satisfaction, future vocational outlook, and quality of life. Consideration of these factors can inform vocational rehabilitation programmes, potentially improving employment outcomes following TBI.

Recovery post treatment: plans, barriers and motivators

PubMed Central

2013-01-01

Background The increasing focus on achieving a sustained recovery from substance use brings with it a need to better understand the factors (recovery capital) that contribute to recovery following treatment. This work examined the factors those in recovery perceive to be barriers to (lack of capital) or facilitators of (presence of capital) sustained recovery post treatment. Methods A purposive sample of 45 participants was recruited from 11 drug treatment services in northern England. Semi-structured qualitative interviews lasting between 30 and 90 minutes were conducted one to three months after participants completed treatment. Interviews examined key themes identified through previous literature but focused on allowing participants to explore their unique recovery journey. Interviews were transcribed and analysed thematically using a combination of deductive and inductive approaches. Results Participants generally reported high levels of confidence in maintaining their recovery with most planning to remain abstinent. There were indications of high levels of recovery capital. Aftercare engagement was high, often through self referral, with non substance use related activity felt to be particularly positive. Supported housing was critical and concerns were raised about the ability to afford to live independently with financial stability and welfare availability a key concern in general. Employment, often in the substance use treatment field, was a desire. However, it was a long term goal, with substantial risks associated with pursuing this too early. Positive social support was almost exclusively from within the recovery community although the re-building of relationships with family (children in particular) was a key motivator post treatment. Conclusions Addressing internal factors and underlying issues i.e. ‘human capital’, provided confidence for continued recovery whilst motivators focused on external factors such as family and maintaining aspects of a ‘normal’ life i.e. ‘social and physical capital’. Competing recovery goals and activities can leave people feeling under pressure and at risk of taking on or being pushed to do too much too soon. The breadth of re-integration and future plans at this stage is limited primarily to the recovery community and treatment sector. Services and commissioners should ensure that this does not become a limiting factor in individuals’ long term recovery journeys. PMID:23363550

Recovery post treatment: plans, barriers and motivators.

PubMed

Duffy, Paul; Baldwin, Helen

2013-01-30

The increasing focus on achieving a sustained recovery from substance use brings with it a need to better understand the factors (recovery capital) that contribute to recovery following treatment. This work examined the factors those in recovery perceive to be barriers to (lack of capital) or facilitators of (presence of capital) sustained recovery post treatment. A purposive sample of 45 participants was recruited from 11 drug treatment services in northern England. Semi-structured qualitative interviews lasting between 30 and 90 minutes were conducted one to three months after participants completed treatment. Interviews examined key themes identified through previous literature but focused on allowing participants to explore their unique recovery journey. Interviews were transcribed and analysed thematically using a combination of deductive and inductive approaches. Participants generally reported high levels of confidence in maintaining their recovery with most planning to remain abstinent. There were indications of high levels of recovery capital. Aftercare engagement was high, often through self referral, with non substance use related activity felt to be particularly positive. Supported housing was critical and concerns were raised about the ability to afford to live independently with financial stability and welfare availability a key concern in general. Employment, often in the substance use treatment field, was a desire. However, it was a long term goal, with substantial risks associated with pursuing this too early. Positive social support was almost exclusively from within the recovery community although the re-building of relationships with family (children in particular) was a key motivator post treatment. Addressing internal factors and underlying issues i.e. 'human capital', provided confidence for continued recovery whilst motivators focused on external factors such as family and maintaining aspects of a 'normal' life i.e. 'social and physical capital'. Competing recovery goals and activities can leave people feeling under pressure and at risk of taking on or being pushed to do too much too soon. The breadth of re-integration and future plans at this stage is limited primarily to the recovery community and treatment sector. Services and commissioners should ensure that this does not become a limiting factor in individuals' long term recovery journeys.

Beyond the limitations of best practices: How logic analysis helped reinterpret dual diagnosis guidelines

PubMed Central

Brousselle, Astrid; Lamothe, Lise; Mercier, Céline; Perreault, Michel

2012-01-01

The co-occurrence of mental health and substance use disorders is becoming increasingly recognized as a single problem, and professionals recognize that both should be addressed at the same time. Medical best practices recommend integrated treatment. However, criticisms have arisen, particularly concerning the difficulty of implementing integrated teams in specific health-care contexts and the appropriateness of the proposed model for certain populations. Using logic analysis, we identify the key clinical and organizational factors that contribute to successful implementation. Building on both the professional and organizational literatures on integrated services, we propose a conceptual model that makes it possible to analyze integration processes and places integrated treatment within an interpretative framework. Using this model, it becomes possible to identify key factors necessary to support service integration, and suggest new models of practice adapted to particular contexts. PMID:17689316

Can sociology help to improve nursing practice?

PubMed

Matthews, David

The first in a five-part series on sociology offers an overview of the debate about the relationship between sociology and nursing. Although sociological education is currently limited within nurse education, there is a long-held argument for its relevance. With a growing emphasis on preventative and public healthcare, sociology may yet prove its usefulness. Subsequent articles cover four of the key social factors affecting health.

ComPratica: A Virtual Community of Practice for Promoting Biology Teachers' Professional Development in Brazil

ERIC Educational Resources Information Center

El-Hani, Charbel N.; Greca, Ileana M.

2013-01-01

Teachers' professional development is a key factor in improving science education, but it shows limited impact when only a small number of teachers is reached, or when it focuses on only one aspect of teachers' development, such as learning science content, and is disconnected from teachers' practice. In order to increase the impact of our work on…

The adaptation of the cerebral circulation to pregnancy: mechanisms and consequences

PubMed Central

Cipolla, Marilyn J

2013-01-01

The adaptation of the cerebral circulation to pregnancy is unique from other vascular beds. Most notably, the growth and vasodilatory response to high levels of circulating growth factors and cytokines that promote substantial hemodynamic changes in other vascular beds is limited in the cerebral circulation. This is accomplished through several mechanisms, including downregulation of key receptors and transcription factors, and production of circulating factors that counteract the vasodilatory effects of vascular endothelial growth factor (VEGF) and placental growth factor. Pregnancy both prevents and reverses hypertensive inward remodeling of cerebral arteries, possibly through downregulation of the angiotensin type 1 receptor. The blood–brain barrier (BBB) importantly adapts to pregnancy by preventing the passage of seizure provoking serum into the brain and limiting the permeability effects of VEGF that is more highly expressed in cerebral vasculature during pregnancy. While the adaptation of the cerebral circulation to pregnancy provides for relatively normal cerebral blood flow and BBB properties in the face of substantial cardiovascular changes and high levels of circulating factors, under pathologic conditions, these adaptations appear to promote greater brain injury, including edema formation during acute hypertension, and greater sensitivity to bacterial endotoxin. PMID:23321787

Using human factors engineering to improve the effectiveness of infection prevention and control.

PubMed

Anderson, Judith; Gosbee, Laura Lin; Bessesen, Mary; Williams, Linda

2010-08-01

Human factors engineering is a discipline that studies the capabilities and limitations of humans and the design of devices and systems for improved performance. The principles of human factors engineering can be applied to infection prevention and control to study the interaction between the healthcare worker and the system that he or she is working with, including the use of devices, the built environment, and the demands and complexities of patient care. Some key challenges in infection prevention, such as delayed feedback to healthcare workers, high cognitive workload, and poor ergonomic design, are explained, as is how human factors engineering can be used for improvement and increased compliance with practices to prevent hospital-acquired infections.

Factors for success in mental health advocacy

PubMed Central

Hann, Katrina; Pearson, Heather; Campbell, Doris; Sesay, Daniel; Eaton, Julian

2015-01-01

Background Mental health advocacy groups are an effective way of pushing the mental health agenda and putting pressure on national governments to observe the right to health; however, there is limited research that highlights best practices for such groups in low-resource settings. In an effort to improve the scaling up of mental health in Sierra Leone, stakeholders came together to form the country's first mental health advocacy group: the Mental Health Coalition – Sierra Leone. Since its inception, the group has worked towards raising the profile of mental health in Sierra Leone and developing as an advocacy organisation. Design The study's aim was to investigate views on enabling factors and barriers associated with mental health advocacy in a low-income country using a community-based participatory approach and qualitative methodology. Focus groups (N=9) were held with mental health stakeholders, and key informant interviews (N=15) were conducted with advocacy targets. Investigators analysed the data collaboratively using coding techniques informed by grounded theory. Results Investigators reveal viewpoints on key factors in networking, interacting with government actors, and awareness raising that enabled mental health advocacy aims of supporting policy, service delivery, service user rights, training for service delivery, and awareness raising. The investigators outline viewpoints on barriers for advocacy aims in framing the issue of mental health, networking, interacting with government actors, resource mobilization, and awareness raising. Conclusions The findings outline enabling factors, such as networking with key stakeholders, and barriers, such as lack of political will, for achieving mental health advocacy aims within a low-resource setting, Sierra Leone. Stakeholder coalitions can further key policy development aims that are essential to strengthen mental health systems in low-resource settings. PMID:26689456

Factors for success in mental health advocacy.

PubMed

Hann, Katrina; Pearson, Heather; Campbell, Doris; Sesay, Daniel; Eaton, Julian

2015-01-01

Mental health advocacy groups are an effective way of pushing the mental health agenda and putting pressure on national governments to observe the right to health; however, there is limited research that highlights best practices for such groups in low-resource settings. In an effort to improve the scaling up of mental health in Sierra Leone, stakeholders came together to form the country's first mental health advocacy group: the Mental Health Coalition - Sierra Leone. Since its inception, the group has worked towards raising the profile of mental health in Sierra Leone and developing as an advocacy organisation. The study's aim was to investigate views on enabling factors and barriers associated with mental health advocacy in a low-income country using a community-based participatory approach and qualitative methodology. Focus groups (N=9) were held with mental health stakeholders, and key informant interviews (N=15) were conducted with advocacy targets. Investigators analysed the data collaboratively using coding techniques informed by grounded theory. Investigators reveal viewpoints on key factors in networking, interacting with government actors, and awareness raising that enabled mental health advocacy aims of supporting policy, service delivery, service user rights, training for service delivery, and awareness raising. The investigators outline viewpoints on barriers for advocacy aims in framing the issue of mental health, networking, interacting with government actors, resource mobilization, and awareness raising. The findings outline enabling factors, such as networking with key stakeholders, and barriers, such as lack of political will, for achieving mental health advocacy aims within a low-resource setting, Sierra Leone. Stakeholder coalitions can further key policy development aims that are essential to strengthen mental health systems in low-resource settings.

Limited interface between physiotherapy primary care and people with severe mental illness: a qualitative study.

PubMed

Lee, Samantha; Waters, Flavie; Briffa, Kathy; Fary, Robyn E

2017-07-01

How do mental health professionals perceive the role of physiotherapists in the care of people with severe and persistent mental illness, and what factors do they perceive as influencing access to physiotherapy services? How do people with severe and persistent mental illness understand the potential role of physiotherapy in their healthcare, and what factors do they perceive as influencing access to physiotherapy services? Qualitative study. Twenty-four mental health professionals and 35 people with severe and persistent mental illness. Interview schedules were developed to explore participants' understanding of physiotherapy, as well as barriers and enablers to service access. Focus groups and interviews were conducted for each group of participants. Transcripts were analysed using an inductive approach to derive key themes. Both the mental health professionals and the people with severe and persistent mental illness expressed a limited understanding of the role and relevance of physiotherapy for physical health in mental healthcare. Common barriers to service access were cost, transport and lack of motivation. Likewise, enablers of reduced cost, provision of transport and education about physiotherapy to improve their understanding were identified. The health system structure and perceived lack of mental health knowledge by physiotherapists influenced referrals from mental health professionals. Consequently, education in mental health for physiotherapists and integration of the service within mental health were identified as potential enablers to physiotherapy access. Limited understanding about physiotherapy and its relevance to physical health in mental healthcare among mental health professionals and people with severe and persistent mental illness was found to be a key factor influencing service access. Limited physiotherapy presence and advocacy within mental health were also highlighted. There is a need for greater understanding about physiotherapy among stakeholders, and for physiotherapists to be well equipped with skills and knowledge in mental health to facilitate greater involvement. [Lee S, Waters F, Briffa K, Fary RE (2017) Limited interface between physiotherapy primary care and people with severe mental illness: a qualitative study. Journal of Physiotherapy 63: 168-174]. Copyright © 2017. Published by Elsevier B.V.

Limitations on quantum key repeaters.

PubMed

Bäuml, Stefan; Christandl, Matthias; Horodecki, Karol; Winter, Andreas

2015-04-23

A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum teleportation. The existence of noisy entangled states that are undistillable but nevertheless useful for quantum key distribution raises the question of the feasibility of a quantum key repeater, which would work beyond the limits of entanglement distillation, hence possibly tolerating higher noise levels than existing protocols. Here we exhibit fundamental limits on such a device in the form of bounds on the rate at which it may extract secure key. As a consequence, we give examples of states suitable for quantum key distribution but unsuitable for the most general quantum key repeater protocol.

Determinants of individuals' participation in integrated chronic disease screening in Singapore.

PubMed

Venkataraman, Kavita; Wee, Hwee Lin; Ng, Sheryl Hui Xian; Rebello, Salome; Tai, E Shyong; Lee, Jeannette; Tan, Chuen Seng

2016-06-10

A large pool of patients with chronic diseases remains undiagnosed globally and in Singapore. We explored factors associated with participation in a health screening exercise, using revealed preference, that is, actual attendance, to understand why people remain undiagnosed with chronic diseases. A cross-sectional, community-based sample of Singapore residents was invited to participate in home interviews, and subsequently to attend centre-based health screening, between 2004 and 2007. Determinants of health screening participation were identified using logistic regression models based on Andersen's Behavioral Model. Of the 6366 participants who completed health interview, 4092 attended the health screening, while 2274 did not. Older age, Chinese or Indian ethnicity, higher education levels, greater intake of monounsaturated fat, greater transport and leisure-time physical activity were the key predisposing factors associated with greater health screening participation. Greater family cohesion was the key associated enabling factor, while previous diagnosis of dyslipidaemia or musculoskeletal conditions, absence of previously diagnosed diabetes or hypertension and lower perceived physical health were the associated need factors. Our study suggests that ethnicity, education, family cohesion, healthy behaviour patterns and perceived physical health status were key determinants of health screening participation. Enhancing the cultural competence of preventive health services may help increase participation of these groups in screening efforts and reduce the proportions of undiagnosed chronic disease in the community. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Back to basics: hand hygiene and isolation

PubMed Central

Lin Huang, G. Khai; Stewardson, Andrew J.; Lindsay Grayson, M.

2014-01-01

Purpose of review Hand hygiene and isolation are basic, but very effective, means of preventing the spread of pathogens in healthcare. Although the principle may be straightforward, this review highlights some of the controversies regarding the implementation and efficacy of these interventions. Recent findings Hand hygiene compliance is an accepted measure of quality and safety in many countries. The evidence for the efficacy of hand hygiene in directly reducing rates of hospital-acquired infections has strengthened in recent years, particularly in terms of reduced rates of staphylococcal sepsis. Defining the key components of effective implementation strategies and the ideal method(s) of assessing hand hygiene compliance are dependent on a range of factors associated with the healthcare system. Although patient isolation continues to be an important strategy, particularly in outbreaks, it also has some limitations and can be associated with negative effects. Recent detailed molecular epidemiology studies of key healthcare-acquired pathogens have questioned the true efficacy of isolation, alone as an effective method for the routine prevention of disease transmission. Summary Hand hygiene and isolation are key components of basic infection control. Recent insights into the benefits, limitations and even adverse effects of these interventions are important for their optimal implementation. PMID:24945613

Photosynthetic limitation as a factor influencing yield in highbush blueberries (Vaccinium corymbosum) grown in a northern European environment.

PubMed

Petridis, Antonios; van der Kaay, Jeroen; Chrysanthou, Elina; McCallum, Susan; Graham, Julie; Hancock, Robert D

2018-05-25

Published evidence indicates that nearly 60% of blueberry-producing countries experience yield instability. Yield is a complex trait determined by genetic and environmental factors. Here, using physiological and biochemical approaches, we tested the hypothesis that yield instability results from year-to-year environmental variation that limits carbon assimilation, storage and partitioning. The data indicate that fruit development depends primarily on the daily production of non-structural carbohydrates by leaves, and there is no accumulation of a starch buffer to allow continuous ripening under conditions limiting for photosynthesis. Photosynthesis was saturated at moderate light irradiance and this was mainly due to stomatal and biochemical limitations. In a dynamic light environment, photosynthesis was further limited by slow stomatal response to increasing light. Finally, labelling with 13CO2 at specific stages of fruit development revealed a relatively even distribution of newly assimilated carbon between stems, roots and fruits, suggesting that the fruit is not a strong sink. We conclude that a significant component of yield variability results from limitations in photosynthetic efficiency that are compounded by an inability to accumulate starch reserves in blueberry storage tissues in a typical northern European environment. This work informs techniques for improving agronomic management and indicates key traits required for yield stability in such environments.

Photosynthetic limitation as a factor influencing yield in highbush blueberries (Vaccinium corymbosum) grown in a northern European environment

PubMed Central

van der Kaay, Jeroen; Chrysanthou, Elina; McCallum, Susan

2018-01-01

Abstract Published evidence indicates that nearly 60% of blueberry-producing countries experience yield instability. Yield is a complex trait determined by genetic and environmental factors. Here, using physiological and biochemical approaches, we tested the hypothesis that yield instability results from year-to-year environmental variation that limits carbon assimilation, storage and partitioning. The data indicate that fruit development depends primarily on the daily production of non-structural carbohydrates by leaves, and there is no accumulation of a starch buffer to allow continuous ripening under conditions limiting for photosynthesis. Photosynthesis was saturated at moderate light irradiance and this was mainly due to stomatal and biochemical limitations. In a dynamic light environment, photosynthesis was further limited by slow stomatal response to increasing light. Finally, labelling with 13CO2 at specific stages of fruit development revealed a relatively even distribution of newly assimilated carbon between stems, roots and fruits, suggesting that the fruit is not a strong sink. We conclude that a significant component of yield variability results from limitations in photosynthetic efficiency that are compounded by an inability to accumulate starch reserves in blueberry storage tissues in a typical northern European environment. This work informs techniques for improving agronomic management and indicates key traits required for yield stability in such environments. PMID:29590429

Risk factors for heat illness among British soldiers in the hot Collective Training Environment

PubMed Central

Moore, Alice C; Stacey, M J; Bailey, K G H; Bunn, R J; Woods, D R; Haworth, K J; Brett, S J; Folkes, S E F

2016-01-01

Background Heat illness is a preventable disorder in military populations. Measures that protect vulnerable individuals and contribute to effective Immediate Treatment may reduce the impact of heat illness, but depend upon adequate understanding and awareness among Commanders and their troops. Objective To assess risk factors for heat illness in British soldiers deployed to the hot Collective Training Environment (CTE) and to explore awareness of Immediate Treatment responses. Methods An anonymous questionnaire was distributed to British soldiers deployed in the hot CTEs of Kenya and Canada. Responses were analysed to determine the prevalence of individual (Intrinsic) and Command-practice (Extrinsic) risk factors for heat illness and the self-reported awareness of key Immediate Treatment priorities (recognition, first aid and casualty evacuation). Results The prevalence of Intrinsic risk factors was relatively low in comparison with Extrinsic risk factors. The majority of respondents were aware of key Immediate Treatment responses. The most frequently reported factors in each domain were increased risk by body composition scoring, inadequate time for heat acclimatisation and insufficient briefing about casualty evacuation. Conclusions Novel data on the distribution and scale of risk factors for heat illness are presented. A collective approach to risk reduction by the accumulation of ‘marginal gains’ is proposed for the UK military. This should focus on limiting Intrinsic risk factors before deployment, reducing Extrinsic factors during training and promoting timely Immediate Treatment responses within the hot CTE. PMID:26036822

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2012-03-01

amputees must be able to manage uneven terrain, crowded environments, stairs , ramps, and hills. The largest problem for a lower extremity amputee is...objective biomechanical variables that are causally related to the success or failure in avoiding a fall after a trip, objective tests to quantify...crowded environments, stairs , ramps, and hills. The key factor that limits the ability of amputees to achieve maximum functional capabilities is falls

Environmental Barrier Coatings for Ceramics and Ceramic Composites

NASA Technical Reports Server (NTRS)

Lee, Kang N.; Fox, Dennis; Eldridge, Jeffrey; Robinson, R. Craig; Bansal, Narottam

2004-01-01

One key factor that limits the performance of current gas turbine engines is the temperature capability of hot section structural components. Silicon-based ceramics, such as SiC/SiC composites and monolithic Si3N4, are leading candidates to replace superalloy hot section components in the next generation gas turbine engines due to their excellent high temperature properties. A major stumbling block to realizing Si-based ceramic hot section components is the recession of Si-based ceramics in combustion environments due to the volatilization of silica scale by water vapor. An external environmental barrier coating (EBC) is the most promising approach to preventing the recession. Current EBCs are based on silicon, mullite (3A12O3-2SiO2) and BSAS (barium strontium aluminum silicate with celsian structure). Volatility of BSAS, BSAS-silica chemical reaction, and low melting point of silicon limit the durability and temperature capability of current EBCs. Research is underway to develop EBCs with longer life and enhanced temperature capability. Understanding key issues affecting the performance of current EBCs is necessary for successful development of advanced EBCs. These issues include stress, chemical compatibility, adherence, and water vapor stability. Factors that affect stress are thermal expansion mismatch, phase stability, chemical stability, elastic modulus, etc. The current understanding on these issues will be discussed.

Modeling environmental influences on child growth in the MAL-ED cohort study: opportunities and challenges.

PubMed

Richard, Stephanie A; McCormick, Benjamin J J; Miller, Mark A; Caulfield, Laura E; Checkley, William

2014-11-01

Although genetics, maternal undernutrition and low birth weight status certainly play a role in child growth, dietary insufficiency and infectious diseases are key risk factors for linear growth faltering during early childhood. A primary goal of the Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) study is to identify specific risk factors associated with growth faltering during the first 2 years of life; however, growth in early childhood is challenging to characterize because growth may be inherently nonlinear with age. In this manuscript, we describe some methods for analyzing longitudinal growth to evaluate both short- and long-term associations between risk factors and growth trajectories over the first 2 years of life across 8 resource-limited settings using harmonized protocols. We expect there will be enough variability within and between sites in the prevalence of risk factors and burden of linear growth faltering to allow us to distinguish some of the key pathways to linear growth faltering in the MAL-ED study. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Impact of segregation energetics on oxygen conductivity at ionic grain boundaries

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

Aidhy, Dilpuneet S; Zhang, Yanwen; Weber, William J

2014-01-01

In pursuit of whether nanocrystallinity could lead to higher anion conductivity, research has revealed contradicting results exposing the limited understanding of point defect energetics at grain boundaries (GBs)/interfaces. By disentangling and addressing key GB energetics issues, i.e., segregation, migration and binding energies of oxygen vacancies in the presence and absence of dopants at the GBs, and the segregation energetics of dopants, we elucidate, using atomic simulations of doped ceria, that dopant segregation is the key factor leading to degradation of oxygen conductivity in nanocrystalline materials. A framework for designing enhanced conducting nanocrystalline materials is proposed where the focus of dopingmore » strategies shifts from bulk to segregation at GBs.« less

A multisource feedback tool to assess ward round leadership skills of senior paediatric trainees: (1) Development of tool.

PubMed

Lakshminarayana, Indumathy; Wall, David; Bindal, Taruna; Goodyear, Helen M

2015-05-01

Leading a ward round is an essential skill for hospital consultants and senior trainees but is rarely assessed during training. To investigate the key attributes for ward round leadership and to use these results to develop a multisource feedback (MSF) tool to assess the ward round leadership skills of senior specialist trainees. A panel of experts comprising four senior paediatric consultants and two nurse managers were interviewed from May to August 2009. From analysis of the interview transcripts, 10 key themes emerged. A structured questionnaire based on the key themes was designed and sent electronically to paediatric consultants, nurses and trainees at a large university hospital (June-October 2010). 81 consultants, nurses and trainees responded to the survey. The internal consistency of this tool was high (Cronbach's α 0.95). Factor analysis showed that five factors accounted for 72% of variance. The five key areas for ward round leadership were communication skills, preparation and organisation, teaching and enthusiasm, team working and punctuality; communication was the most important key theme. A MSF tool for ward round leadership skills was developed with these areas as five domains. We believe that this tool will add to the current assessment tools available by providing feedback about ward round leadership skills. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Role of Nuclear Factor Erythroid 2-Related Factor 2 in Diabetic Nephropathy

PubMed Central

Min, Xu; Xu, Xiaohong

2017-01-01

Diabetic nephropathy (DN) is manifested as increased urinary protein level, decreased glomerular filtration rate, and final renal dysfunction. DN is the leading cause of end-stage renal disease worldwide and causes a huge societal healthcare burden. Since satisfied treatments are still limited, exploring new strategies for the treatment of this disease is urgently needed. Oxidative stress takes part in the initiation and development of DN. In addition, nuclear factor erythroid 2-related factor 2 (Nrf2) plays a key role in the cellular response to oxidative stress. Thus, activation of Nrf2 seems to be a new choice for the treatment of DN. In current review, we discussed and summarized the therapeutic effects of Nrf2 activation on DN from both basic and clinical studies. PMID:28512642

Performance analysis of air-water quantum key distribution with an irregular sea surface

NASA Astrophysics Data System (ADS)

Xu, Hua-bin; Zhou, Yuan-yuan; Zhou, Xue-jun; Wang, Lian

2018-05-01

In the air-water quantum key distribution (QKD), the irregular sea surface has some influence on the photon polarization state. The wind is considered as the main factor causing the irregularity, so the model of irregular sea surface based on the wind speed is adopted. The relationships of the quantum bit error rate with the wind speed and the initial incident angle are simulated. Therefore, the maximum secure transmission depth of QKD is confirmed, and the limitation of the wind speed and the initial incident angle is determined. The simulation results show that when the wind speed and the initial incident angle increase, the performance of QKD will fall down. Under the intercept-resend attack condition, the maximum safe transmission depth of QKD is up to 105 m. To realize safe communications in the safe diving depth of submarines (100 m), the initial incident angle is requested to be not exceeding 26°, and with the initial incident angle increased, the limitation of wind speed is decreased.

Comparison of data used for setting occupational exposure limits.

PubMed

Schenk, Linda

2010-01-01

It has previously been shown that occupational exposure limits (OELs) for the same substance can vary significantly between different standard-setters. The work presented in this paper identifies the steps in the process towards establishing an OEL and how variations in those processes could account for these differences. This study selects for further scrutiny substances for which the level of OELs vary by a factor of 100, focussing on 45 documents concerning 14 substances from eight standard-setters. Several of the OELs studied were more than 20 years old and based on outdated knowledge. Furthermore, different standard-setters sometimes based their OELs on different sets of data, and data availability alone could not explain all differences in the selection of data sets used by standard-setters. While the interpretation of key studies did not differ significantly in standard-setters' documentations, the evaluations of the key studies' quality did. Also, differences concerning the critical effect coincided with differences in the level of OELs for half of the substances.

Layered Location-Based Security Mechanism for Mobile Sensor Networks: Moving Security Areas.

PubMed

Wang, Ze; Zhang, Haijuan; Wu, Luqiang; Zhou, Chang

2015-09-25

Network security is one of the most important issues in mobile sensor networks (MSNs). Networks are particularly vulnerable in hostile environments because of many factors, such as uncertain mobility, limitations on computation, and the need for storage in mobile nodes. Though some location-based security mechanisms can resist some malicious attacks, they are only suitable for static networks and may sometimes require large amounts of storage. To solve these problems, using location information, which is one of the most important properties in outdoor wireless networks, a security mechanism called a moving security area (MSA) is proposed to resist malicious attacks by using mobile nodes' dynamic location-based keys. The security mechanism is layered by performing different detection schemes inside or outside the MSA. The location-based private keys will be updated only at the appropriate moments, considering the balance of cost and security performance. By transferring parts of the detection tasks from ordinary nodes to the sink node, the memory requirements are distributed to different entities to save limited energy.

Particle Engineering in Pharmaceutical Solids Processing: Surface Energy 
Considerations

PubMed Central

Williams, Daryl R.

2015-01-01

During the past 10 years particle engineering in the pharmaceutical industry has become a topic of increasing importance. Engineers and pharmacists need to understand and control a range of key unit manufacturing operations such as milling, granulation, crystallisation, powder mixing and dry powder inhaled drugs which can be very challenging. It has now become very clear that in many of these particle processing operations, the surface energy of the starting, intermediate or final products is a key factor in understanding the processing operation and or the final product performance. This review will consider the surface energy and surface energy heterogeneity of crystalline solids, methods for the measurement of surface energy, effects of milling on powder surface energy, adhesion and cohesion on powder mixtures, crystal habits and surface energy, surface energy and powder granulation processes, performance of DPI systems and finally crystallisation conditions and surface energy. This review will conclude that the importance of surface energy as a significant factor in understanding the performance of many particulate pharmaceutical products and processes has now been clearly established. It is still nevertheless, work in progress both in terms of development of methods and establishing the limits for when surface energy is the key variable of relevance. PMID:25876912

Identification of the key ecological factors influencing vegetation degradation in semi-arid agro-pastoral ecotone considering spatial scales

NASA Astrophysics Data System (ADS)

Peng, Yu; Wang, Qinghui; Fan, Min

2017-11-01

When assessing re-vegetation project performance and optimizing land management, identification of the key ecological factors inducing vegetation degradation has crucial implications. Rainfall, temperature, elevation, slope, aspect, land use type, and human disturbance are ecological factors affecting the status of vegetation index. However, at different spatial scales, the key factors may vary. Using Helin County, Inner-Mongolia, China as the study site and combining remote sensing image interpretation, field surveying, and mathematical methods, this study assesses key ecological factors affecting vegetation degradation under different spatial scales in a semi-arid agro-pastoral ecotone. It indicates that the key factors are different at various spatial scales. Elevation, rainfall, and temperature are identified as crucial for all spatial extents. Elevation, rainfall and human disturbance are key factors for small-scale quadrats of 300 m × 300 m and 600 m × 600 m, temperature and land use type are key factors for a medium-scale quadrat of 1 km × 1 km, and rainfall, temperature, and land use are key factors for large-scale quadrats of 2 km × 2 km and 5 km × 5 km. For this region, human disturbance is not the key factor for vegetation degradation across spatial scales. It is necessary to consider spatial scale for the identification of key factors determining vegetation characteristics. The eco-restoration programs at various spatial scales should identify key influencing factors according their scales so as to take effective measurements. The new understanding obtained in this study may help to explore the forces which driving vegetation degradation in the degraded regions in the world.

Which key properties controls the preferential transport in the vadose zone under transient hydrological conditions

NASA Astrophysics Data System (ADS)

Groh, J.; Vanderborght, J.; Puetz, T.; Gerke, H. H.; Rupp, H.; Wollschlaeger, U.; Stumpp, C.; Priesack, E.; Vereecken, H.

2015-12-01

Understanding water flow and solute transport in the unsaturated zone is of great importance for an appropriate land use management strategy. The quantification and prediction of water and solute fluxes through the vadose zone can help to improve management practices in order to limit potential risk on our fresh water resources. Water related solute transport and residence time is strongly affected by preferential flow paths in the soil. Water flow in soils depends on soil properties and site factors (climate or experiment conditions, land use) and are therefore important factors to understand preferential solute transport in the unsaturated zone. However our understanding and knowledge of which on-site properties or conditions define and enhance preferential flow and transport is still poor and mostly limited onto laboratory experimental conditions (small column length and steady state boundary conditions). Within the TERENO SOILCan lysimeter network, which was designed to study the effects of climate change on soil functions, a bromide tracer was applied on 62 lysimeter at eight different test sites between Dec. 2013 and Jan. 2014. The TERENO SOILCan infrastructure offers the unique possibility to study the occurrence of preferential flow and transport of various soil types under different natural transient hydrological conditions and land use (crop, bare and grassland) at eight TERENO SOILCan observatories. Working with lysimeter replicates at each observatory allows defining the spatial variability of preferential transport and flow. Additionally lysimeters in the network were transferred within and between observatories in order to subject them to different rainfall and temperature regimes and enable us to relate the soil type susceptibility of preferential flow and transport not only to site specific physical and land use properties, but also to different transient boundary conditions. Comparison and statistical analysis between preferential flow indicators 5% arrival time and potential key soil properties, site factors and boundary conditions will be presented in order to identify key properties which control the preferential transport in the vadose zone under transient hydrological conditions.

[Goals, possibilities and limits of quality evaluation of guidelines. A background report on the user manual of the "Methodological Quality of Guidelines" check list].

PubMed

Helou, A; Ollenschläger, G

1998-06-01

Recently a German appraisal instrument for clinical guidelines was published that could be used by various parties in formal evaluation of guidelines. An user's guide to the appraisal instrument was designed that contains a detailed explanation for each question to ensure that the instrument is interpreted consistently. This paper describes the purposes, format and contents of the user's guide, and reviews the key factors influencing the validity of guidelines. Taking into account international experiences, the purposes, chances and methodological limitations of a prospective assessment of clinical practice guidelines are discussed.

Genetic improvement of leaf photosynthesis and intrinsic water use efficiency in C3 plants: Why so much little success?

PubMed

Flexas, J

2016-10-01

There is an urgent need for simultaneously increasing photosynthesis/yields and water use efficiency (WUE) in C3 crops. Potentially, this can be achieved by genetic manipulation of the key traits involved. However, despite significant efforts in the past two decades very limited success has been achieved. Here I argue that this is mostly due to the fact that single gene/single trait approaches have been used thus far. Photosynthesis models demonstrate that only limited improving of photosynthesis can be expected by large improvements of any of its single limiting factors, i.e. stomatal conductance, mesophyll conductance, and the biochemical capacity for photosynthesis, the latter co-limited by Rubisco and the orchestrated activity of thylakoid electron transport and the Calvin cycle enzymes. Accordingly, only limited improvements of photosynthesis have been obtained by genetic manipulation of any of these single factors. In addition, improving photosynthesis by genetic manipulation in general reduced WUE, and vice-versa, and in many cases pleiotropic effects appear that cancel out some of the expected benefits. I propose that success in genetic manipulation for simultaneous improvement of photosynthesis and WUE efficiency may take longer than suggested in previous reports, and that it can be achieved only by joint projects addressing multi-gene manipulation for simultaneous alterations of all the limiting factors of photosynthesis, including the often neglected phloem capacity for loading and transport the expected surplus of carbohydrates in plants with improved photosynthesis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

High Data Rate Quantum Cryptography

NASA Astrophysics Data System (ADS)

Kwiat, Paul; Christensen, Bradley; McCusker, Kevin; Kumor, Daniel; Gauthier, Daniel

2015-05-01

While quantum key distribution (QKD) systems are now commercially available, the data rate is a limiting factor for some desired applications (e.g., secure video transmission). Most QKD systems receive at most a single random bit per detection event, causing the data rate to be limited by the saturation of the single-photon detectors. Recent experiments have begun to explore using larger degree of freedoms, i.e., temporal or spatial qubits, to optimize the data rate. Here, we continue this exploration using entanglement in multiple degrees of freedom. That is, we use simultaneous temporal and polarization entanglement to reach up to 8.3 bits of randomness per coincident detection. Due to current technology, we are unable to fully secure the temporal degree of freedom against all possible future attacks; however, by assuming a technologically-limited eavesdropper, we are able to obtain 23.4 MB/s secure key rate across an optical table, after error reconciliation and privacy amplification. In this talk, we will describe our high-rate QKD experiment, with a short discussion on our work towards extending this system to ship-to-ship and ship-to-shore communication, aiming to secure the temporal degree of freedom and to implement a 30-km free-space link over a marine environment.

The Federal Aviation Administration Plan for Research, Engineering and Development. Volume 2. Project Descriptions

DTIC Science & Technology

1989-01-01

managerial areas , including: management and control of the operational requirements of the NAS F& E Plan; preparation, management, and control of the annual... areas (capacity, safety, security, and efficiency), highlights of key programs, and a discussion of the relationships of the RE&D Plan to the NAS F& E ...release of SUA , such as restricted airspace and military operations areas , are currently limited by several factors, including manual interagency

Silicon photonics integrated circuits: a manufacturing platform for high density, low power optical I/O's.

PubMed

Absil, Philippe P; Verheyen, Peter; De Heyn, Peter; Pantouvaki, Marianna; Lepage, Guy; De Coster, Jeroen; Van Campenhout, Joris

2015-04-06

Silicon photonics integrated circuits are considered to enable future computing systems with optical input-outputs co-packaged with CMOS chips to circumvent the limitations of electrical interfaces. In this paper we present the recent progress made to enable dense multiplexing by exploiting the integration advantage of silicon photonics integrated circuits. We also discuss the manufacturability of such circuits, a key factor for a wide adoption of this technology.

Extending the Endurance, Missions and Capabilities of Most UAVs Using Advanced Flexible/Ridged Solar Cells and New High Power Density Batteries Technology

DTIC Science & Technology

2011-03-01

68 3. Photovoltaic Effect ..........................69 4. Factors Affecting Cell Efficiency ............69 D. THIN-FILM...resistance. (After [3])...........................................120  xvi Table 21.  Average battery capacity (AH) and battery energy capacity (WH...which is directly limited by the on-board battery capacity . The other key drawbacks are the weight and size of the mini- xviii UAV, which restrict the

Training the Trainers: Mission Analysis and Support for USAR Training Divisions

DTIC Science & Technology

1991-03-25

the Department of Defense (DOD),! mobilization expansion is a key factor In Limited Mobilization9 or Graduated Military Responseio theories of...less filled units of their personnel to fill earlier deploying units. After stripping units at random with 19 disastrous morale results it was decided...28 assigned) once all companies In the division are filled. This mission is identified in the unit’s Table of Distribution and Allowance ( TDA ) and

Immune function trade-offs in response to parasite threats.

PubMed

Kirschman, Lucas J; Quade, Adam H; Zera, Anthony J; Warne, Robin W

2017-04-01

Immune function is often involved in physiological trade-offs because of the energetic costs of maintaining constitutive immunity and mounting responses to infection. However, immune function is a collection of discrete immunity factors and animals should allocate towards factors that combat the parasite threat with the highest fitness cost. For example, animals on dispersal fronts of expanding population may be released from density-dependent diseases. The costs of immunity, however, and life history trade-offs in general, are often context dependent. Trade-offs are often most apparent under conditions of unusually limited resources or when animals are particularly stressed, because the stress response can shift priorities. In this study we tested how humoral and cellular immune factors vary between phenotypes of a wing dimorphic cricket and how physiological stress influences these immune factors. We measured constitutive lysozyme activity, a humoral immune factor, and encapsulation response, a cellular immune factor. We also stressed the crickets with a sham predator in a full factorial design. We found that immune strategy could be explained by the selective pressures encountered by each morph and that stress decreased encapsulation, but not lysozyme activity. These results suggest a possible trade-off between humoral and cellular immunity. Given limited resources and the expense of immune factors, parasite pressures could play a key factor in maintaining insect polyphenism via disruptive selection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Health care financing in Asia: key issues and challenges.

PubMed

Kwon, Soonman

2011-09-01

This article examines the major elements of health care financing such as financial risk protection, resource generation, resource pooling, and purchasing and payment; provides key lessons; and discusses the challenges for health care financing systems of Asian countries. With the exception of Japan, Korea, Taiwan, and Thailand, most health care systems of Asia provide very limited financial risk protection. The role of public prepaid schemes such as tax and social health insurance is minimal, and out-of-pocket payment is a major source of financing. The large informal sector is a major challenge to the extension of population coverage in many low-income countries of Asia, which must seek the optimal mix of tax subsidy and health insurance for universal coverage. Implementation of effective payment systems to control the behavior of health care providers is also a key factor in the success of health care financing reform in Asia.

Brain abnormalities in antisocial individuals: implications for the law.

PubMed

Yang, Yaling; Glenn, Andrea L; Raine, Adrian

2008-01-01

With the increasing popularity in the use of brain imaging on antisocial individuals, an increasing number of brain imaging studies have revealed structural and functional impairments in antisocial, psychopathic, and violent individuals. This review summarizes key findings from brain imaging studies on antisocial/aggressive behavior. Key regions commonly found to be impaired in antisocial populations include the prefrontal cortex (particularly orbitofrontal and dorsolateral prefrontal cortex), superior temporal gyrus, amygdala-hippocampal complex, and anterior cingulate cortex. Key functions of these regions are reviewed to provide a better understanding on how deficits in these regions may predispose to antisocial behavior. Objections to the use of imaging findings in a legal context are outlined, and alternative perspectives raised. It is argued that brain dysfunction is a risk factor for antisocial behavior and that it is likely that imaging will play an increasing (albeit limited) role in legal decision-making. (c) 2008 John Wiley & Sons, Ltd.

Explaining the increasing disability prevalence among mid-life US adults, 2002 to 2016.

PubMed

Zajacova, Anna; Montez, Jennifer Karas

2018-05-24

Several recent studies have documented an alarming upward trend in disability and functional limitations among US adults. In this study, we draw on the sociomedical Disablement Process framework to produce up-to-date estimates of the trends and identify key social and medical precursors of the trends. Using data on US adults aged 45-64 in the 2002-2016 National Health Interview Surveys, we estimate parametric and semiparametric models of disability and functional limitations as a function of interview time. We also determine the impact of socioeconomic resources, health behaviors, and health conditions on the trends. Our results show increasing prevalence of disability and functional limitations. These trends reflect the net result of complex countervailing forces, some associated with increases in functioning problems (unfavorable trends in economic well-being, especially income, and psychological distress) while other factors have suppressed the growth of functioning problems (favorable trends in educational attainment and some health behaviors, such as smoking and alcohol use). The results underscore that disability prevention must expand beyond medical interventions to include fundamental social factors and be focused on preventing or delaying the onset of chronic health problems and functional limitations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Model-based analysis of environmental controls over ecosystem primary production in an alpine tundra dry meadow

DOE PAGES

Fan, Zhaosheng; Neff, Jason C.; Wieder, William R.

2016-02-10

We investigated several key limiting factors that control alpine tundra productivity by developing an ecosystem biogeochemistry model. The model simulates the coupled cycling of carbon (C), nitrogen (N), and phosphorus (P) and their interactions with gross primary production (GPP). It was parameterized with field observations from an alpine dry meadow ecosystem using a global optimization strategy to estimate the unknown parameters. The model, along with the estimated parameters, was first validated against independent data and then used to examine the environmental controls over plant productivity. Our results show that air temperature is the strongest limiting factor to GPP in themore » early growing season, N availability becomes important during the middle portion of the growing season, and soil moisture is the strongest limiting factors by late in the growing season. Overall, the controls over GPP during the growing season, from strongest to weakest, are soil moisture content, air temperature, N availability, and P availability. This simulation provides testable predictions of the shifting nature of physical and nutrient limitations on plant growth. The model also indicates that changing environmental conditions in the alpine will likely lead to changes in productivity. For example, warming eliminates the control of P availability on GPP and makes N availability surpass air temperature to become the second strongest limiting factor. In contrast, an increase in atmospheric nutrient deposition eliminates the control of N availability and enhances the importance of P availability. Furthermore, these analyses provide a quantitative and conceptual framework that can be used to test predictions and refine ecological analyses at this long-term ecological research site.« less

Model-based analysis of environmental controls over ecosystem primary production in an alpine tundra dry meadow

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

Fan, Zhaosheng; Neff, Jason C.; Wieder, William R.

We investigated several key limiting factors that control alpine tundra productivity by developing an ecosystem biogeochemistry model. The model simulates the coupled cycling of carbon (C), nitrogen (N), and phosphorus (P) and their interactions with gross primary production (GPP). It was parameterized with field observations from an alpine dry meadow ecosystem using a global optimization strategy to estimate the unknown parameters. The model, along with the estimated parameters, was first validated against independent data and then used to examine the environmental controls over plant productivity. Our results show that air temperature is the strongest limiting factor to GPP in themore » early growing season, N availability becomes important during the middle portion of the growing season, and soil moisture is the strongest limiting factors by late in the growing season. Overall, the controls over GPP during the growing season, from strongest to weakest, are soil moisture content, air temperature, N availability, and P availability. This simulation provides testable predictions of the shifting nature of physical and nutrient limitations on plant growth. The model also indicates that changing environmental conditions in the alpine will likely lead to changes in productivity. For example, warming eliminates the control of P availability on GPP and makes N availability surpass air temperature to become the second strongest limiting factor. In contrast, an increase in atmospheric nutrient deposition eliminates the control of N availability and enhances the importance of P availability. Furthermore, these analyses provide a quantitative and conceptual framework that can be used to test predictions and refine ecological analyses at this long-term ecological research site.« less

The fourth dimension in immunological space: how the struggle for nutrients selects high-affinity lymphocytes.

PubMed

Wensveen, Felix M; van Gisbergen, Klaas P J M; Eldering, Eric

2012-09-01

Lymphocyte activation via the antigen receptor is associated with radical shifts in metabolism and changes in requirements for nutrients and cytokines. Concomitantly, drastic changes occur in the expression of pro-and anti-apoptotic proteins that alter the sensitivity of lymphocytes to limiting concentrations of key survival factors. Antigen affinity is a primary determinant for the capacity of activated lymphocytes to access these vital resources. The shift in metabolic needs and the variable access to key survival factors is used by the immune system to eliminate activated low-affinity cells and to generate an optimal high-affinity response. In this review, we focus on the control of apoptosis regulators in activated lymphocytes by nutrients, cytokines, and costimulation. We propose that the struggle among individual clones that leads to the formation of high-affinity effector cell populations is in effect an 'invisible' fourth signal required for effective immune responses. © 2012 John Wiley & Sons A/S.

Microscale optical cryptography using a subdiffraction-limit optical key

NASA Astrophysics Data System (ADS)

Ogura, Yusuke; Aino, Masahiko; Tanida, Jun

2018-04-01

We present microscale optical cryptography using a subdiffraction-limit optical pattern, which is finer than the diffraction-limit size of the decrypting optical system, as a key and a substrate with a reflectance distribution as an encrypted image. Because of the subdiffraction-limit spatial coding, this method enables us to construct a secret image with the diffraction-limit resolution. Simulation and experimental results demonstrate, both qualitatively and quantitatively, that the secret image becomes recognizable when and only when the substrate is illuminated with the designed key pattern.

Hydrologic dynamics and ecosystem structure.

PubMed

Rodríguez-Iturbe, I

2003-01-01

Ecohydrology is the science that studies the mutual interaction between the hydrological cycle and ecosystems. Such an interaction is especially intense in water-controlled ecosystems, where water may be a limiting factor, not only because of its scarcity, but also because of its intermittent and unpredictable appearance. Hydrologic dynamics is shown to be a crucial factor for ecological patterns and processes. The probabilistic structure of soil moisture in time and space is presented as the key linkage between soil, climate and vegetation dynamics. Nutrient cycles, vegetation coexistence and plant response to environmental conditions are all intimately linked to the stochastic fluctuation of the hydrologic inputs driving an ecosystem.

A longitudinal test of the predictions of the interpersonal-psychological theory of suicidal behaviour for passive and active suicidal ideation in a large community-based cohort.

PubMed

Batterham, Philip J; Walker, Jennie; Leach, Liana S; Ma, Jennifer; Calear, Alison L; Christensen, Helen

2018-02-01

The Interpersonal-Psychological Theory of Suicide (IPTS) aims to elucidate the key antecedents of suicide deaths. Limited research has tested the IPTS in a community setting, and very little longitudinal research has been conducted. The current study longitudinally tested the predictions of the IPTS for suicidal ideation in a large population-based sample. The PATH through Life study assesses three age cohorts (20's, 40's, 60's) every four years. Two interpersonal factors were estimated at the third wave of assessment: thwarted belongingness (TB) and perceived burdensomeness (PB). The roles of these factors in suicide ideation (active and passive) four years later were estimated using logistic regression models (n = 4545). A one SD increase in TB was associated with increased odds of 37% for passive ideation and 24% for active ideation. For PB, odds were increased 2.5-fold for passive ideation and 2.4-fold for active ideation. A significant negative PB × TB interaction was found for passive but not active ideation. Effects were not consistent by age group or gender. Proxy measures were used to assess the constructs. The extended timeframe and low prevalence of suicidal ideation limited power to find effects within subgroups. Although TB and PB were individually associated with suicidal thoughts, little evidence was found for the key predictions of the IPTS longitudinally. Further investigation of the dynamic interplay between interpersonal factors over time is needed. Copyright © 2017 Elsevier B.V. All rights reserved.

High-Fluence Light-Emitting Diode-Generated Red Light Modulates the Transforming Growth Factor-Beta Pathway in Human Skin Fibroblasts.

PubMed

Mamalis, Andrew; Jagdeo, Jared

2018-05-24

Skin fibrosis is a significant medical problem with limited available treatment modalities. The key cellular characteristics include increased fibroblast proliferation, collagen production, and transforming growth factor-beta (TGF-B)/SMAD pathway signaling. The authors have previously shown that high-fluence light-emitting diode red light (HF-LED-RL) decreases cellular proliferation and collagen production. Herein, the authors investigate the ability of HF-LED-RL to modulate the TGF-B/SMAD pathway. Normal human dermal fibroblasts were cultured and irradiated with a commercially available hand-held LED array. After irradiation, cell lysates were collected and levels of pSMAD2, TGF-Beta 1, and TGF-Beta I receptor were measured using Western blot. High-fluence light-emitting diode red light decreased TGF-Beta 1 ligand (TGF-B1) levels after irradiation. 320 J/cm HF-LED-RL resulted in 59% TGF-B1 and 640 J/cm HF-LED-RL resulted in 54% TGF-B1, relative to controls. 640 J/cm HF-LED-RL resulted in 62% pSMAD2 0 hours after irradiation, 65% pSMAD2 2 hours after irradiation, and 95% 4 hours after irradiation, compared with matched controls. High-fluence light-emitting diode red light resulted in no significant difference in transforming growth factor-beta receptor I levels compared with matched controls. Skin fibrosis is a significant medical problem with limited available treatment modalities. Light-emitting diode-generated red light is a safe, economic, and noninvasive modality that has a body of in vitro evidence supporting the reduction of key cellular characteristics associated with skin fibrosis.

Population Attributable and Preventable Fractions: Cancer Risk Factor Surveillance, and Cancer Policy Projection

PubMed Central

Shield, Kevin D.; Parkin, D. Maxwell; Whiteman, David C.; Rehm, Jürgen; Viallon, Vivian; Micallef, Claire Marant; Vineis, Paolo; Rushton, Lesley; Bray, Freddie; Soerjomataram, Isabelle

2016-01-01

The proportions of new cancer cases and deaths that are caused by exposure to risk factors and that could be prevented are key statistics for public health policy and planning. This paper summarizes the methodologies for estimating, challenges in the analysis of, and utility of, population attributable and preventable fractions for cancers caused by major risk factors such as tobacco smoking, dietary factors, high body fat, physical inactivity, alcohol consumption, infectious agents, occupational exposure, air pollution, sun exposure, and insufficient breastfeeding. For population attributable and preventable fractions, evidence of a causal relationship between a risk factor and cancer, outcome (such as incidence and mortality), exposure distribution, relative risk, theoretical-minimum-risk, and counterfactual scenarios need to be clearly defined and congruent. Despite limitations of the methodology and the data used for estimations, the population attributable and preventable fractions are a useful tool for public health policy and planning. PMID:27547696

A mental health needs assessment of children and adolescents in post-conflict Liberia: results from a quantitative key-informant survey

PubMed Central

Borba, Christina P.C.; Ng, Lauren C.; Stevenson, Anne; Vesga-Lopez, Oriana; Harris, Benjamin L.; Parnarouskis, Lindsey; Gray, Deborah A.; Carney, Julia R.; Domínguez, Silvia; Wang, Edward K.S.; Boxill, Ryan; Song, Suzan J.; Henderson, David C.

2016-01-01

Between 1989 and 2004, Liberia experienced a devastating civil war that resulted in widespread trauma with almost no mental health infrastructure to help citizens cope. In 2009, the Liberian Ministry of Health and Social Welfare collaborated with researchers from Massachusetts General Hospital to conduct a rapid needs assessment survey in Liberia with local key informants (n = 171) to examine the impact of war and post-war events on emotional and behavioral problems of, functional limitations of, and appropriate treatment settings for Liberian youth aged 5–22. War exposure and post-conflict sexual violence, poverty, infectious disease and parental death negatively impacted youth mental health. Key informants perceived that youth displayed internalizing and externalizing symptoms and mental health-related functional impairment at home, school, work and in relationships. Medical clinics were identified as the most appropriate setting for mental health services. Youth in Liberia continue to endure the harsh social, economic and material conditions of everyday life in a protracted post-conflict state, and have significant mental health needs. Their observed functional impairment due to mental health issues further limited their access to protective factors such as education, employment and positive social relationships. Results from this study informed Liberia's first post-conflict mental health policy. PMID:26807147

A mental health needs assessment of children and adolescents in post-conflict Liberia: results from a quantitative key-informant survey.

PubMed

Borba, Christina P C; Ng, Lauren C; Stevenson, Anne; Vesga-Lopez, Oriana; Harris, Benjamin L; Parnarouskis, Lindsey; Gray, Deborah A; Carney, Julia R; Domínguez, Silvia; Wang, Edward K S; Boxill, Ryan; Song, Suzan J; Henderson, David C

2016-01-02

Between 1989 and 2004, Liberia experienced a devastating civil war that resulted in widespread trauma with almost no mental health infrastructure to help citizens cope. In 2009, the Liberian Ministry of Health and Social Welfare collaborated with researchers from Massachusetts General Hospital to conduct a rapid needs assessment survey in Liberia with local key informants ( n = 171) to examine the impact of war and post-war events on emotional and behavioral problems of, functional limitations of, and appropriate treatment settings for Liberian youth aged 5-22. War exposure and post-conflict sexual violence, poverty, infectious disease and parental death negatively impacted youth mental health. Key informants perceived that youth displayed internalizing and externalizing symptoms and mental health-related functional impairment at home, school, work and in relationships. Medical clinics were identified as the most appropriate setting for mental health services. Youth in Liberia continue to endure the harsh social, economic and material conditions of everyday life in a protracted post-conflict state, and have significant mental health needs. Their observed functional impairment due to mental health issues further limited their access to protective factors such as education, employment and positive social relationships. Results from this study informed Liberia's first post-conflict mental health policy.

The Relationship Between Post-Migration Stress and Psychological Disorders in Refugees and Asylum Seekers.

PubMed

Li, Susan S Y; Liddell, Belinda J; Nickerson, Angela

2016-09-01

Refugees demonstrate high rates of post-traumatic stress disorder (PTSD) and other psychological disorders. The recent increase in forcible displacement internationally necessitates the understanding of factors associated with refugee mental health. While pre-migration trauma is recognized as a key predictor of mental health outcomes in refugees and asylum seekers, research has increasingly focused on the psychological effects of post-migration stressors in the settlement environment. This article reviews the research evidence linking post-migration factors and mental health outcomes in refugees and asylum seekers. Findings indicate that socioeconomic, social, and interpersonal factors, as well as factors relating to the asylum process and immigration policy affect the psychological functioning of refugees. Limitations of the existing literature and future directions for research are discussed, along with implications for treatment and policy.

Analysis of Key Factors Driving Japan’s Military Normalization

DTIC Science & Technology

2017-09-01

Clay Moltz THIS PAGE INTENTIONALLY LEFT BLANK i REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704–0188 Public reporting burden for this collection...Unclassified 19. SECURITY CLASSIFICATION OF ABSTRACT Unclassified 20. LIMITATION OF ABSTRACT UU NSN 7540–01-280-5500 Standard Form 298 (Rev. 2...agenda. Most people pointed to the rise of China, the end of wars in the Middle East, and regional shifts in reliance on fossil fuels, among other issues

Responding to the Language Challenge: Kaiser Permanente's Approach

PubMed Central

Meyers, Kate; Tang, Gayle; Fernandez, Alicia

2009-01-01

Objective: To inform current debates on improving health care quality for patients with limited English proficiency by identifying the drivers and processes for one large health care delivery system's implementation of particular models, key success factors, and remaining challenges for the field. Study Design: A qualitative case study of the Kaiser Permanente (KP) San Francisco Medical Center's approach to developing linguistic access services and subsequent organizationwide initiatives. Methods: We conducted semistructured interviews with eight current and former clinical and administrative leaders from the KP San Francisco Medical Center and national headquarters. Interviews were analyzed for key themes. Results: KP San Francisco Medical Center developed linguistic and cultural services in response to a confluence of external and internal factors, including changing demographics, care quality challenges, and patient and clinician satisfaction issues. Early strategies included development of language-specific care modules focused on Chinese- and Spanish-speaking members while meeting broader linguistic access and cultural-competency needs through a centralized Multicultural Services Center. Additional approaches across KP regions have focused on improving interpreter services, optimizing use of bilingual staff, and creating a translation infrastructure to improve quality and reduce redundancy in written translation efforts. Conclusions: KP's experiences developing linguistic and cultural care and services since the 1990s provide lessons about decision-making processes and approaches that may guide other health systems, insurers, and policy makers striving to improve care quality and safety for patients with limited English proficiency. PMID:20740094

Physiotherapy, rehabilitation and sports in countries with limited replacement coagulation factor supply.

PubMed

Buzzard, B M

2007-09-01

It is well documented that physiotherapy and rehabilitation benefit people with haemophilia by strengthening the key muscle groups and protecting joints from the adverse effects of repeated haemorrhages. Rehabilitation, in conjunction with the availability of replacement coagulation factor products, has revolutionized approaches to the management of patients with haemophilia in developed countries and has led to a substantial decrease in both the morbidity and mortality rates among the haemophilic population. Modern treatment approaches have also enabled persons with haemophilia to participate in sporting activities along with their peers; however, these improvements in care have not been achieved in developing nations, where health-care resources and facilities are scarce and the supply of coagulation factor products is limited. This article attempts to address the following questions about the management of haemophilic patients in developing countries: Can physiotherapy, rehabilitation and sports prevent disabilities and preserve independence? Is participation in sports activities possible in developing countries? Do countries differ with regard to guidelines for participation in sports? Should we be encouraging participation in sports or allowing patients with haemophilia to do as they choose?

Team learning and innovation in nursing, a review of the literature.

PubMed

Timmermans, Olaf; Van Linge, Roland; Van Petegem, Peter; Van Rompaey, Bart; Denekens, Joke

2012-01-01

The capability to learn and innovate has been recognized as a key-factor for nursing teams to deliver high quality performance. Researchers suggest there is a relation between team-learning activities and changes in nursing teams throughout the implementation of novelties. A review of the literature was conducted in regard to the relation between team learning and implementation of innovations in nursing teams and to explore factors that contribute or hinder team learning. The search was limited to studies that were published in English or Dutch between 1998 and 2010. Eight studies were included in the review. The results of this review revealed that research on team learning and innovation in nursing is limited. The included studies showed moderate methodological quality and low levels of evidence. Team learning included processes to gather, process, and store information from different innovations within the nursing team and the prevalence of team-learning activities was contributed or hindered by individual and contextual factors. Further research is needed on the relation between team learning and implementation of innovations in nursing. Copyright © 2011 Elsevier Ltd. All rights reserved.

Human Cytomegalovirus Strategies to Maintain and Promote mRNA Translation

PubMed Central

Vincent, Heather A.; Ziehr, Benjamin; Moorman, Nathaniel J.

2016-01-01

mRNA translation requires the ordered assembly of translation initiation factors and ribosomal subunits on a transcript. Host signaling pathways regulate each step in this process to match levels of protein synthesis to environmental cues. In response to infection, cells activate multiple defenses that limit viral protein synthesis, which viruses must counteract to successfully replicate. Human cytomegalovirus (HCMV) inhibits host defenses that limit viral protein expression and manipulates host signaling pathways to promote the expression of both host and viral proteins necessary for virus replication. Here we review key regulatory steps in mRNA translation, and the strategies used by HCMV to maintain protein synthesis in infected cells. PMID:27089357

Accounting for Ethnicity-Related Differences in Ocular Surface Integrity as a Step Toward Understanding Contact Lens Discomfort.

PubMed

Chan, Stefanie M; Svitova, Tatyana F; Lin, Meng C

2017-01-01

Contact lens discomfort is a common problem that can lead to unsuccessful or limited contact lens wear. Although many factors may contribute to contact lens discomfort, limited research has explored the influence of ethnicity-related differences in the anatomy and physiology of the ocular surface. Therefore, we performed a search of the literature in PubMed using key words related to "ocular surface" paired with the terms "race" and "ethnicity." The goal of this review was to determine potential areas of research regarding ethnicity differences, particularly between Asian and non-Asian eyes, in ocular surface integrity to advance our understanding of contact lens discomfort.

The interplay between cognitive risk and resilience factors in remitted depression: A network analysis.

PubMed

Hoorelbeke, Kristof; Marchetti, Igor; De Schryver, Maarten; Koster, Ernst H W

2016-05-01

Individuals in remission from depression are at increased risk for developing future depressive episodes. Several cognitive risk- and resilience factors have been suggested to account for this vulnerability. In the current study we explored how risk- and protective factors such as cognitive control, adaptive and maladaptive emotion regulation, residual symptomatology, and resilience relate to one another in a remitted depressed (RMD) sample. We examined the relationships between these constructs in a cross-sectional dataset of 69 RMD patients using network analyses in order to obtain a comprehensive, data-driven view on the interplay between these constructs. We subsequently present an association network, a concentration network, and a relative importance network. In all three networks resilience formed the central hub, connecting perceived cognitive control (i.e., working memory complaints), emotion regulation, and residual symptomatology. The contribution of the behavioral measure for cognitive control in the network was negligible. Moreover, the directed relative importance network indicates bidirectional influences between these constructs, with all indicators of centrality suggesting a key role of resilience in remission from depression. The presented findings are cross-sectional and networks are limited to a fixed set of key constructs in the literature pertaining cognitive vulnerability for depression. These findings indicate the importance of resilience to successfully cope with stressors following remission from depression. Further in-depth studies will be essential to identify the specific underlying resilience mechanisms that may be key to successful remission from depression. Copyright © 2016 Elsevier B.V. All rights reserved.

Challenges for health care development in Croatia.

PubMed

Ostojić, Rajko; Bilas, Vlatka; Franc, Sanja

2012-09-01

The main aim of the research done in this paper was to establish key challenges and perspectives for health care development in the Republic of Croatia in the next two decades. Empirical research was conducted in the form of semi-structured interviews involving 49 subjects, representatives of health care professionals from both, public and private sectors, health insurance companies, pharmaceutical companies, drug wholesalers, and non-governmental organisations (patient associations). The results have shown that key challenges and problems of Croatian health care can be divided into three groups: functioning of health care systems, health care personnel, and external factors. Research has shown that key challenges related to the functioning of health care are inefficiency, financial unviability, inadequate infrastructure, and the lack of system transparency. Poor governance is another limiting factor. With regard to health care personnel, they face the problems of low salaries, which then lead to migration challenges and a potential shortage of health care personnel. The following external factors are deemed to be among the most significant challenges: ageing population, bad living habits, and an increase in the number of chronic diseases. However, problems caused by the global financial crisis and consequential macroeconomic situation must not be neglected. Guidelines for responding to challenges identified in this research are the backbone for developing a strategy for health care development in the Republic of Croatia. Long-term vision, strategy, policies, and a regulatory framework are all necessary preconditions for an efficient health care system and more quality health services.

Litter decomposition, N2-fixer abundance, and microbial dynamics govern tropical dry forest recovery to land use change

NASA Astrophysics Data System (ADS)

Trierweiler, A.; Powers, J. S.; Xu, X.; Gei, M. G.; Medvigy, D.

2017-12-01

As one of the most threatened tropical biomes, Seasonal Dry Tropical Forests (TDF) have undergone extensive land-use change. However, some areas are undergoing recovery into secondary forests. Despite their broad distribution (42% of tropical forests), they are under-studied compared to wet tropical forests and our understanding of their biogeochemical cycling and belowground processes are limited. Here, we use models along with field measurements to improve our understanding of nutrient cycling and limitation in secondary TDFs. We ask (1) Is there modeling evidence that tropical dry forests can become nutrient limited? (2) What are the most important mechanisms employed to avoid nutrient limitation? (3) How might climate change alter biogeochemical cycling and nutrient limitation in recovering TDF? We use a new version of the Ecosystem Demography (ED2) model that has been recently parameterized for TDFs and incorporates a range of plant functional groups (including deciduousness and N2-fixation) and multiple resource constraints (carbon, nitrogen, phosphorus, and water). In the model, plants then can dynamically adjust their carbon allocation and nutrient acquisition strategies using N2-fixing bacteria and mycorrhizal fungi according to the nutrient limitation status. We ran the model for a nutrient gradient of field sites in Costa Rica and explored the sensitivity of nutrient limitation to key mechanisms including litter respiration, N resorption, N2-fixation, and overflow respiration. Future runs will evaluate how CO2 and climate change affect recovering TDFs. We found increasing nutrient limitation across the nutrient gradient of sites. Nitrogen limitation dominated the nutrient limitation signal. In the model, forest litter accumulation was negatively correlated with site fertility in Costa Rican forests. Our sensitivity analyses indicate that N2-fixer abundance, decomposition rates, and adding more explicit microbial dynamics are key factors in overcoming this limitation. These insights improve our understanding of how TDFs function and are especially relevant to the management of recovering secondary TDFs by highlighting potential bottlenecks in the recovery process.

Probabilistic cost estimates for climate change mitigation.

PubMed

Rogelj, Joeri; McCollum, David L; Reisinger, Andy; Meinshausen, Malte; Riahi, Keywan

2013-01-03

For more than a decade, the target of keeping global warming below 2 °C has been a key focus of the international climate debate. In response, the scientific community has published a number of scenario studies that estimate the costs of achieving such a target. Producing these estimates remains a challenge, particularly because of relatively well known, but poorly quantified, uncertainties, and owing to limited integration of scientific knowledge across disciplines. The integrated assessment community, on the one hand, has extensively assessed the influence of technological and socio-economic uncertainties on low-carbon scenarios and associated costs. The climate modelling community, on the other hand, has spent years improving its understanding of the geophysical response of the Earth system to emissions of greenhouse gases. This geophysical response remains a key uncertainty in the cost of mitigation scenarios but has been integrated with assessments of other uncertainties in only a rudimentary manner, that is, for equilibrium conditions. Here we bridge this gap between the two research communities by generating distributions of the costs associated with limiting transient global temperature increase to below specific values, taking into account uncertainties in four factors: geophysical, technological, social and political. We find that political choices that delay mitigation have the largest effect on the cost-risk distribution, followed by geophysical uncertainties, social factors influencing future energy demand and, lastly, technological uncertainties surrounding the availability of greenhouse gas mitigation options. Our information on temperature risk and mitigation costs provides crucial information for policy-making, because it clarifies the relative importance of mitigation costs, energy demand and the timing of global action in reducing the risk of exceeding a global temperature increase of 2 °C, or other limits such as 3 °C or 1.5 °C, across a wide range of scenarios.

Artificial gravity considerations for a mars exploration mission

NASA Technical Reports Server (NTRS)

Young, L. R.

1999-01-01

Artificial gravity (AG), as a means of preventing physiological deconditioning of astronauts during long-duration space flights, presents certain special challenges to the otolith organs and the adaptive capabilities of the CNS. The key issues regarding the choice of AG acceleration, radius, and rotation rate are reviewed from the viewpoints of physiological requirements and human factors disturbances. Head movements and resultant Coriolis forces on the rotating platform may limit the usefulness of economical short centrifuges for other than brief periods of intermittent stimulation.

A review on the factors affecting mite growth in stored grain commodities.

PubMed

Collins, D A

2012-03-01

A thorough review of the literature has identified the key factors and interactions that affect the growth of mite pests on stored grain commodities. Although many factors influence mite growth, the change and combinations of the physical conditions (temperature, relative humidity and/or moisture content) during the storage period are likely to have the greatest impact, with biological factors (e.g. predators and commodity) playing an important role. There is limited information on the effects of climate change, light, species interactions, local density dependant factors, spread of mycotoxins and action thresholds for mites. A greater understanding of these factors may identify alternative control techniques. The ability to predict mite population dynamics over a range of environmental conditions, both physical and biological, is essential in providing an early warning of mite infestations, advising when appropriate control measures are required and for evaluating control measures. This information may provide a useful aid in predicting and preventing mite population development as part of a risk based decision support system.

Effects of different growth factors and carriers on bone regeneration: a systematic review.

PubMed

Khojasteh, Arash; Behnia, Hossein; Naghdi, Navid; Esmaeelinejad, Mohammad; Alikhassy, Zahra; Stevens, Mark

2013-12-01

The application and subsequent investigations in the use of varied osteogenic growth factors in bone regeneration procedures have grown dramatically over the past several years. Owing to this rapid gain in popularity and documentation, a review was undertaken to evaluate the in vivo effects of growth factors on bone regeneration. Using related key words, electronic databases (Medline, Embase, and Cochrane) were searched for articles published from 1999 to April 2010 to find growth factor application in bone regeneration in human or animal models. A total of 63 articles were matched with the inclusion criteria of this study. Bone morphogenetic protein 2 (BMP-2) was the most studied growth factor. Carriers for the delivery, experimental sites, and methods of evaluation were different, and therefore articles did not come to a general agreement. Within the limitations of this review, BMP-2 may be an appropriate growth factor for osteogenesis. Copyright © 2013 Elsevier Inc. All rights reserved.

Anaesthesia in outer space: the ultimate ambulatory setting?

PubMed

Komorowski, Matthieu; Fleming, Sarah; Hinkelbein, Jochen

2016-12-01

Missions to the Moon or more distant planets are planned in the next future, and will push back the limits of our experience in providing medical support in remote environments. Medical preparedness is ongoing, and involves planning for emergency surgical interventions and anaesthetic procedures. This review will summarize what principles of ambulatory anaesthesia on Earth could benefit the environment of a space mission with its unique constraints. Ambulatory anaesthesia relies on several principles such as improved patient pathway, correct patient selection, optimized procedural strategies to hasten recovery and active prevention of postoperative complications. Severe limitations in the equipment available and the skills of the crew members represent the key factors to be taken into account when designing the on-board medical system for future interplanetary space missions. The application of some of the key principles of ambulatory anaesthesia, as well as recent advances in anaesthetic techniques and better understanding of human adaptation to the space environment might allow nonanaesthesiologist physicians to perform common anaesthetic procedures, whilst maximizing crew safety and minimizing the impact of medical events on the mission.

Case-mix adjustment for diabetes indicators: a systematic review.

PubMed

Calsbeek, Hiske; Markhorst, Joekle G M; Voerman, Gerlienke E; Braspenning, Jozé C C

2016-02-01

Case-mix adjustment is generally considered indispensable for fair comparison of healthcare performance. Inaccurate results are also unfair to patients as they are ineffective for improving quality. However, little is known about what factors should be adjusted for. We reviewed case-mix factors included in adjustment models for key diabetes indicators, the rationale for their inclusion, and their impact on performance. Systematic review. This systematic review included studies published up to June 2013 addressing case-mix factors for 6 key diabetes indicators: 2 outcomes and 2 process indicators for glycated hemoglobin (A1C), low-density lipoprotein cholesterol, and blood pressure. Factors were categorized as demographic, diabetes-related, comorbidity, generic health, geographic, or care-seeking, and were evaluated on the rationale for inclusion in the adjustment models, as well as their impact on indicator scores and ranking. Thirteen studies were included, mainly addressing A1C value and measurement. Twenty-three different case-mix factors, mostly demographic and diabetes-related, were identified, and varied from 1 to 14 per adjustment model. Six studies provided selection motives for the inclusion of case-mix factors. Marital status and body mass index showed a significant impact on A1C value. For the other factors, either no or conflicting associations were reported, or too few studies (n ≤ 2) investigated this association. Scientific knowledge about the relative importance of case-mix factors for diabetes indicators is emerging, especially for demographic and diabetes-related factors and indicators on A1C, but is still limited. Because arbitrary adjustment potentially results in inaccurate quality information, meaningful stratification that demonstrates inequity in care might be a better guide, as it can be a driver for quality improvement.

The physical size of transcription factors is key to transcriptional regulation in chromatin domains

NASA Astrophysics Data System (ADS)

Maeshima, Kazuhiro; Kaizu, Kazunari; Tamura, Sachiko; Nozaki, Tadasu; Kokubo, Tetsuro; Takahashi, Koichi

2015-02-01

Genetic information, which is stored in the long strand of genomic DNA as chromatin, must be scanned and read out by various transcription factors. First, gene-specific transcription factors, which are relatively small (˜50 kDa), scan the genome and bind regulatory elements. Such factors then recruit general transcription factors, Mediators, RNA polymerases, nucleosome remodellers, and histone modifiers, most of which are large protein complexes of 1-3 MDa in size. Here, we propose a new model for the functional significance of the size of transcription factors (or complexes) for gene regulation of chromatin domains. Recent findings suggest that chromatin consists of irregularly folded nucleosome fibres (10 nm fibres) and forms numerous condensed domains (e.g., topologically associating domains). Although the flexibility and dynamics of chromatin allow repositioning of genes within the condensed domains, the size exclusion effect of the domain may limit accessibility of DNA sequences by transcription factors. We used Monte Carlo computer simulations to determine the physical size limit of transcription factors that can enter condensed chromatin domains. Small gene-specific transcription factors can penetrate into the chromatin domains and search their target sequences, whereas large transcription complexes cannot enter the domain. Due to this property, once a large complex binds its target site via gene-specific factors it can act as a ‘buoy’ to keep the target region on the surface of the condensed domain and maintain transcriptional competency. This size-dependent specialization of target-scanning and surface-tethering functions could provide novel insight into the mechanisms of various DNA transactions, such as DNA replication and repair/recombination.

Aerodynamic Performance of a Compact, High Work-Factor Centrifugal Compressor at the Stage and Subcomponent Level

NASA Technical Reports Server (NTRS)

Braunscheidel, Edward P.; Welch, Gerard E.; Skoch, Gary J.; Medic, Gorazd; Sharma, Om P.

2014-01-01

The measured aerodynamic performance of a compact, high work factor, single-stage centrifugal compressor, comprising an impeller, diffuser, 90-bend, and exit guide vane (EGV), is reported. Performance levels are based on steady-state total-pressure and total-temperature rake and angularity-probe data acquired at key machine rating planes during recent testing at NASA Glenn Research Center. Aerodynamic performance at the stage level are reported for operation between 70 to 105 of design corrected speed, with subcomponent (impeller, diffuser, and exitguide-vane) detailed flow field measurements presented and discussed at the 100 design-speed condition. Individual component losses from measurements are compared with pre-test predictions on a limited basis.

Applying Computerized-Scoring Models of Written Biological Explanations across Courses and Colleges: Prospects and Limitations

PubMed Central

Ha, Minsu; Nehm, Ross H.; Urban-Lurain, Mark; Merrill, John E.

2011-01-01

Our study explored the prospects and limitations of using machine-learning software to score introductory biology students’ written explanations of evolutionary change. We investigated three research questions: 1) Do scoring models built using student responses at one university function effectively at another university? 2) How many human-scored student responses are needed to build scoring models suitable for cross-institutional application? 3) What factors limit computer-scoring efficacy, and how can these factors be mitigated? To answer these questions, two biology experts scored a corpus of 2556 short-answer explanations (from biology majors and nonmajors) at two universities for the presence or absence of five key concepts of evolution. Human- and computer-generated scores were compared using kappa agreement statistics. We found that machine-learning software was capable in most cases of accurately evaluating the degree of scientific sophistication in undergraduate majors’ and nonmajors’ written explanations of evolutionary change. In cases in which the software did not perform at the benchmark of “near-perfect” agreement (kappa > 0.80), we located the causes of poor performance and identified a series of strategies for their mitigation. Machine-learning software holds promise as an assessment tool for use in undergraduate biology education, but like most assessment tools, it is also characterized by limitations. PMID:22135372

Applying computerized-scoring models of written biological explanations across courses and colleges: prospects and limitations.

PubMed

Ha, Minsu; Nehm, Ross H; Urban-Lurain, Mark; Merrill, John E

2011-01-01

Our study explored the prospects and limitations of using machine-learning software to score introductory biology students' written explanations of evolutionary change. We investigated three research questions: 1) Do scoring models built using student responses at one university function effectively at another university? 2) How many human-scored student responses are needed to build scoring models suitable for cross-institutional application? 3) What factors limit computer-scoring efficacy, and how can these factors be mitigated? To answer these questions, two biology experts scored a corpus of 2556 short-answer explanations (from biology majors and nonmajors) at two universities for the presence or absence of five key concepts of evolution. Human- and computer-generated scores were compared using kappa agreement statistics. We found that machine-learning software was capable in most cases of accurately evaluating the degree of scientific sophistication in undergraduate majors' and nonmajors' written explanations of evolutionary change. In cases in which the software did not perform at the benchmark of "near-perfect" agreement (kappa > 0.80), we located the causes of poor performance and identified a series of strategies for their mitigation. Machine-learning software holds promise as an assessment tool for use in undergraduate biology education, but like most assessment tools, it is also characterized by limitations.

[Adoption of new technologies by health services: the challenge of analyzing relevant factors].

PubMed

Trindade, Evelinda

2008-05-01

The exponential increase in the incorporation of health technologies has been considered a key factor in increased expenditures by the health sector. Such decisions involve multiple levels and stakeholders. Decentralization has multiplied the decision-making levels, with numerous difficult choices and limited resources. The interrelationship between stakeholders is complex, in creative systems with multiple determinants and confounders. The current review discusses the interaction between the factors influencing the decisions to incorporate technologies by health services, and proposes a structure for their analysis. The application and intensity of these factors in decision-making and the incorporation of products and programs by health services shapes the installed capacity of local and regional networks and modifies the health system. Empirical observation of decision-making and technology incorporation in Brazilian health services poses an important challenge. The structured recognition and measurement of these variables can assist proactive planning of health services.

Identifying mental health issues in detained youth: Testing the structure and invariance of the Massachusetts Youth Screening Inventory-Version 2 (MAYSI-2).

PubMed

Russell, Justin D; Marsee, Monica A; Ryals, John S

2017-06-01

This study examined the factor structure of the Massachusetts Youth Screening Instrument-Version 2 (MAYSI-2), a brief self-report measure designed to flag clinically significant mental health needs among youth entering the juvenile justice system. Participants were 981 detained youth in the southeastern United States (mean age = 14.58 years; SD = 1.28 years; 67.5% male; 71.5% African American). Confirmatory factor analyses showed that a seven-factor model represented a satisfactory solution for the data, similar to previous research. The factor structure fit well across gender, age group, race (Black/White), and offense type (violent/nonviolent). Given the widespread use of the MAYSI-2 in juvenile justice settings, examining its psychometric properties is of key importance. Implications and limitations of the study are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

ROS mediated selection for increased NADPH availability in Escherichia coli.

PubMed

Reynolds, Thomas S; Courtney, Colleen M; Erickson, Keesha E; Wolfe, Lisa M; Chatterjee, Anushree; Nagpal, Prashant; Gill, Ryan T

2017-11-01

The economical production of chemicals and fuels by microbial processes remains an intense area of interest in biotechnology. A key limitation in such efforts concerns the availability of key co-factors, in this case NADPH, required for target pathways. Many of the strategies pursued for increasing NADPH availability in Escherichia coli involve manipulations to the central metabolism, which can create redox imbalances and overall growth defects. In this study we used a reactive oxygen species based selection to search for novel methods of increasing NADPH availability. We report a loss of function mutation in the gene hdfR appears to increase NADPH availability in E. coli. Additionally, we show this excess NADPH can be used to improve the production of 3HP in E. coli. © 2017 Wiley Periodicals, Inc.

App Usage Factor: A Simple Metric to Compare the Population Impact of Mobile Medical Apps.

PubMed

Lewis, Thomas Lorchan; Wyatt, Jeremy C

2015-08-19

One factor when assessing the quality of mobile apps is quantifying the impact of a given app on a population. There is currently no metric which can be used to compare the population impact of a mobile app across different health care disciplines. The objective of this study is to create a novel metric to characterize the impact of a mobile app on a population. We developed the simple novel metric, app usage factor (AUF), defined as the logarithm of the product of the number of active users of a mobile app with the median number of daily uses of the app. The behavior of this metric was modeled using simulated modeling in Python, a general-purpose programming language. Three simulations were conducted to explore the temporal and numerical stability of our metric and a simulated app ecosystem model using a simulated dataset of 20,000 apps. Simulations confirmed the metric was stable between predicted usage limits and remained stable at extremes of these limits. Analysis of a simulated dataset of 20,000 apps calculated an average value for the app usage factor of 4.90 (SD 0.78). A temporal simulation showed that the metric remained stable over time and suitable limits for its use were identified. A key component when assessing app risk and potential harm is understanding the potential population impact of each mobile app. Our metric has many potential uses for a wide range of stakeholders in the app ecosystem, including users, regulators, developers, and health care professionals. Furthermore, this metric forms part of the overall estimate of risk and potential for harm or benefit posed by a mobile medical app. We identify the merits and limitations of this metric, as well as potential avenues for future validation and research.

Human Health and Performance Considerations for Exploration of Near-Earth Asteroids

NASA Technical Reports Server (NTRS)

Kundrot, Craig; Steinberg, Susan; Charles, John

2010-01-01

This presentation will describe the human health and performance issues that are anticipated for the human exploration of near-Earth asteroids (NEA). Humans are considered a system in the design of any such deep-space exploration mission, and exploration of NEA presents unique challenges for the human system. Key factors that define the mission are those that are strongly affected by distance and duration. The most critical of these is deep-space radiation exposure without even the temporary shielding of a nearby large planetary body. The current space radiation permissible exposure limits (PEL) restrict mission duration to 3-10 months depending on age and gender of crewmembers and stage of the solar cycle. Factors that affect mission architecture include medical capability; countermeasures for bone, muscle, and cardiovascular atrophy during continuous weightlessness; restricted food supplies; and limited habitable volume. The design of a habitat that can maintain the physical and psychological health of the crew and support mission operations with limited intervention from Earth will require an integrated research and development effort by NASA s Human Research Program, engineering, and human factors groups. Limited abort and return options for an NEA mission are anticipated to have important effects on crew psychology as well as influence medical supplies and training requirements of the crew. Other important factors are those related to isolation, confinement, communication delays, autonomous operations, task design, small crew size, and even the unchanging view outside the windows for most of the mission. Geological properties of the NEA will influence design of sample handling and containment, and extravehicular activity capabilities including suit ports and tools. A robotic precursor mission that collects basic information on NEA surface properties would reduce uncertainty about these aspects of the mission as well as aid in design of mission architecture and exploration tasks.

Recommendations for the Improved Effectiveness and Reporting of Telemedicine Programs in Developing Countries: Results of a Systematic Literature Review.

PubMed

Khanal, Sumesh; Burgon, Joseph; Leonard, Saoirse; Griffiths, Matthew; Eddowes, Lucy A

2015-11-01

A lack of decisive evidence on the impact of telemedicine on financial and clinical outcomes has not prohibited significant investment in developing countries. Understanding characteristics that facilitate effective telemedicine programs is required to allow telemedicine to be used to its full potential. This systematic review aimed to identify organizational, technological, and financial features of successful telemedicine programs providing direct clinical care in developing countries. Databases were searched, and the results were reviewed systematically according to predefined inclusion/exclusion criteria. Information on location(s), measure of success, and organizational, technological, and financial characteristics were extracted. This review was impeded by inadequate program reporting, and so a concise checklist was developed to aid improved reporting, enabling future reviews to identify key characteristics of effective programs. This systematic review identified 46 articles reporting 36 programs that fulfilled the inclusion/exclusion criteria. Programs were distributed globally, including regional, national, and international programs. Technological modalities included synchronous technology, real-time teleconsultations, and asynchronous technology. Program integration with existing systems and twinning of international institutions were identified as factors enabling program success. Other factors included simple and easy-to-use technology, ability to reduce the burden on healthcare professionals, and technology able to maintain functionality in challenging environmental circumstances. Reports describing effectiveness and costs were limited. This systematic review identified key factors associated with telemedicine program success. However, inconsistencies in reporting represent an obstacle to establishment of successful programs in developing countries by limiting the application of previous experiences. Adhering to the guidelines suggested here may allow more quantitative assessments of effectiveness and impact for future programs.

Projecting distribution of the overwintering population of Sogatella furcifera (Hemiptera: Delphacidae), in Yunnan, China with analysis on key influencing climatic factors.

PubMed

Hu, Shao-Ji; Liu, Xiao-Fei; Fu, Da-Ying; Huang, Wei; Wang, Xue-Ying; Liu, Xiao-Jun; Lü, Jian-Ping; Ye, Hui

2015-01-01

Sogatella furcifera (Horváth) is the most threatening migratory rice pest in Yunnan, China. S. furcifera overwinters in low- altitude basins and valleys in southern Yunnan and migrates northward in spring and summer of the following year, causing serious damage during migration. The overwintering distribution, areas, and spatial pattern of S. furcifera are relevant to the migration and outbreak of this pest. Based on a 4-yr field survey (2010-2013), this study projected areas suitable for S. furcifera to overwinter using a species distribution model, and analyzed the key influencing climatic factors using principal component analysis (PCA) and ecological niche factor analysis (ENFA). Our field survey showed that the northern latitudinal- and upper elevation limits of overwintering S. furcifera was 25.4° N and 1,608 m in western Yunnan and 24.2° N and 1,563 m in eastern Yunnan. The species distribution model produced a fragmented distribution pattern, with most of which in western Yunnan and only a few in eastern Yunnan. The PCA and ENFA analyses showed that the mean temperature of the driest quarter and the precipitation of the coldest quarter significantly influenced the distribution of S. furcifera in winter. The results suggested that the complex topography, spatial differences in winter temperatures, and host availability altogether determined the distribution of overwintering S. furcifera. Compared with previous surveys, the northern latitudinal- and upper elevation limits of overwintering S. furcifera were higher, while the population became rarer in some suitable areas due to change of farmland utilization in winter and possibly climate change. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

Patient complaints in healthcare services in Vietnam’s health system

PubMed Central

Thi Thu Ha, Bui; Mirzoev, Tolib; Morgan, Rosemary

2015-01-01

Background: There is growing recognition of patient rights in health sectors around the world. Patients’ right to complain in hospitals, often visible in legislative and regulatory protocols, can be an important information source for service quality improvement and achievement of better health outcomes. However, empirical evidence on complaint processes is scarce, particularly in the developing countries. To contribute in addressing this gap, we investigated patients’ complaint handling processes and the main influences on their implementation in public hospitals in Vietnam. Methods: The study was conducted in two provinces of Vietnam. We focused specifically on the implementation of the Law on Complaints and Denunciations and the Ministry of Health regulation on resolving complaints in the health sector. The data were collected using document review and in-depth interviews with key respondents. Framework approach was used for data analysis, guided by a conceptual framework and aided by qualitative data analysis software. Results: Five steps of complaint handling were implemented, which varied in practice between the provinces. Four groups of factors influenced the procedures: (1) insufficient investment in complaint handling procedures; (2) limited monitoring of complaint processes; (3) patients’ low awareness of, and perceived lack of power to change, complaint procedures and (4) autonomization pressures on local health facilities. While the existence of complaint handling processes is evident in the health system in Vietnam, their utilization was often limited. Different factors which constrained the implementation and use of complaint regulations included health system–related issues as well as social and cultural influences. Conclusion: The study aimed to contribute to improved understanding of complaint handling processes and the key factors influencing these processes in public hospitals in Vietnam. Specific policy implications for improving these processes were proposed, which include improving accountability of service providers and better utilization of information on complaints. PMID:26770804

Feedback-assisted extension of the tokamak operating space to low safety factor

DOE PAGES

Hanson, Jeremy M.; Bialek, James M.; Baruzzo, M.; ...

2014-07-07

Recent DIII-D and RFX-mod experiments have demonstrated stable tokamak operation at very low values of the edge safety factor q( a) near and below 2. The onset of n = 1 resistive wall mode (RWM) kink instabilities leads to a disruptive stability limit, encountered at q( a) = 2 (limiter plasmas) and q 95 = 2 (divertor plasmas). However, passively stable operation can be attained for q( a) and q 95 values as low as 2.2. RWM damping in the q( a) = 2 regime was measured using active MHD spectroscopy. Although consistent with theoretical predictions, the amplitude of themore » damped response does not increase significantly as the q( a) = 2 limit is approached, in contrast with damping measurements made approaching the pressure-driven RWM limit. Applying proportional gain magnetic feedback control of the n = 1 modes has resulted in stabilized operation with q 95 values reaching as low as 1.9 in DIII-D and q( a) reaching 1.55 in RFX-mod. In addition to being consistent with the q( a) = 2 external kink mode stability limit, the unstable modes have growth rates on the order of the characteristic wall eddy-current decay timescale in both devices, and a dominant m = 2 poloidal structure that is consistent with ideal MHD predictions. As a result, the experiments contribute to validating MHD stability theory and demonstrate that a key tokamak stability limit can be overcome with feedback.« less

What is the most prominent factor limiting photosynthesis in different layers of a greenhouse cucumber canopy?

PubMed Central

Chen, Tsu-Wei; Henke, Michael; de Visser, Pieter H. B.; Buck-Sorlin, Gerhard; Wiechers, Dirk; Kahlen, Katrin; Stützel, Hartmut

2014-01-01

Background and Aims Maximizing photosynthesis at the canopy level is important for enhancing crop yield, and this requires insights into the limiting factors of photosynthesis. Using greenhouse cucumber (Cucumis sativus) as an example, this study provides a novel approach to quantify different components of photosynthetic limitations at the leaf level and to upscale these limitations to different canopy layers and the whole plant. Methods A static virtual three-dimensional canopy structure was constructed using digitized plant data in GroIMP. Light interception of the leaves was simulated by a ray-tracer and used to compute leaf photosynthesis. Different components of photosynthetic limitations, namely stomatal (SL), mesophyll (ML), biochemical (BL) and light (LL) limitations, were calculated by a quantitative limitation analysis of photosynthesis under different light regimes. Key Results In the virtual cucumber canopy, BL and LL were the most prominent factors limiting whole-plant photosynthesis. Diffusional limitations (SL + ML) contributed <15 % to total limitation. Photosynthesis in the lower canopy was more limited by the biochemical capacity, and the upper canopy was more sensitive to light than other canopy parts. Although leaves in the upper canopy received more light, their photosynthesis was more light restricted than in the leaves of the lower canopy, especially when the light condition above the canopy was poor. An increase in whole-plant photosynthesis under diffuse light did not result from an improvement of light use efficiency but from an increase in light interception. Diffuse light increased the photosynthesis of leaves that were directly shaded by other leaves in the canopy by up to 55 %. Conclusions Based on the results, maintaining biochemical capacity of the middle–lower canopy and increasing the leaf area of the upper canopy would be promising strategies to improve canopy photosynthesis in a high-wire cucumber cropping system. Further analyses using the approach described in this study can be expected to provide insights into the influences of horticultural practices on canopy photosynthesis and the design of optimal crop canopies. PMID:24907313

Interactions of water quality and integrated groundwater management: Examples from the United States and Europe: Chapter 14

USGS Publications Warehouse

Warner, Kelly L.; Barataud, Fabienne; Hunt, Randall J.; Benoit, Marc; Anglade, Juliette; Borchardt, Mark A.

2015-01-01

Groundwater is available in many parts of the world, but the quality of the water may limit its use. Contaminants can limit the use of groundwater through concerns associated with human health, aquatic health, economic costs, or even societal perception. Given this broad range of concerns, this chapter focuses on examples of how water quality issues influence integrated groundwater management. One example evaluates the importance of a naturally occurring contaminant Arsenic (As) for drinking water supply, one explores issues resulting from agricultural activities on the land surface and factors that influence related groundwater management, and the last examines unique issues that result from human-introduced viral pathogens for groundwater-derived drinking water vulnerability. The examples underscore how integrated groundwater management lies at the intersections of environmental characterization, engineering constraints, societal needs, and human perception of acceptable water quality. As such, water quality factors can be a key driver for societal decision making.

Oscillator Noise Analysis

NASA Astrophysics Data System (ADS)

Demir, Alper

2005-08-01

Oscillators are key components of many kinds of systems, particularly electronic and opto-electronic systems. Undesired perturbations, i.e. noise, that exist in practical systems adversely affect the spectral and timing properties of the signals generated by oscillators resulting in phase noise and timing jitter. These are key performance limiting factors, being major contributors to bit-error-rate (BER) of RF and optical communication systems, and creating synchronization problems in clocked and sampled-data electronic systems. In noise analysis for oscillators, the key is figuring out how the various disturbances and noise sources in the oscillator end up as phase fluctuations. In doing so, one first computes transfer functions from the noise sources to the oscillator phase, or the sensitivity of the oscillator phase to these noise sources. In this paper, we first provide a discussion explaining the origins and the proper definition of this transfer or sensitivity function, followed by a critical review of the various numerical techniques for its computation that have been proposed by various authors over the past fifteen years.

Approaches to a global quantum key distribution network

NASA Astrophysics Data System (ADS)

Islam, Tanvirul; Bedington, Robert; Ling, Alexander

2017-10-01

Progress in realising quantum computers threatens to weaken existing public key encryption infrastructure. A global quantum key distribution (QKD) network can play a role in computational attack-resistant encryption. Such a network could use a constellation of high altitude platforms such as airships and satellites as trusted nodes to facilitate QKD between any two points on the globe on demand. This requires both space-to-ground and inter-platform links. However, the prohibitive cost of traditional satellite based development limits the experimental work demonstrating relevant technologies. To accelerate progress towards a global network, we use an emerging class of shoe-box sized spacecraft known as CubeSats. We have designed a polarization entangled photon pair source that can operate on board CubeSats. The robustness and miniature form factor of our entanglement source makes it especially suitable for performing pathfinder missions that studies QKD between two high altitude platforms. The technological outcomes of such mission would be the essential building blocks for a global QKD network.

Helping people change: the magic of motivation.

PubMed

Jameson, Cathy

2003-01-01

The consensus of the data and of the interviewed doctors was that the five most profound motivators of people in the workplace today are as follows: (1) Achievement of work well done; (2) Personal pride and satisfaction in being a part of quality treatment and excellent care of patients; (3) Continuing education; (4) Equitable compensation; (5) Respect, responsibility, and appreciation. When asked how important motivation is to the productivity of her practice, Dr. Stelly closes by saying, "Motivation is the most critical factor in productivity. Motivation is the key. If everyone is on the same page and if the doctor and key team members can continue to motivate and encourage others, then the sky is the limit. The key is to keep everyone goal-oriented, unified, and excited about the possibilities. Then you are going to have a team of consistent, long-term employees, you don't have turnover and with that kind of consistency, you are going to have increased productivity."

Ethnographic field work in requirements engineering

NASA Astrophysics Data System (ADS)

Reddivari, Sandeep; Asaithambi, Asai; Niu, Nan; Wang, Wentao; Xu, Li Da; Cheng, Jing-Ru C.

2017-01-01

The requirements engineering (RE) processes have become a key in developing and deploying enterprise information system (EIS) for organisations and corporations in various fields and industrial sectors. Ethnography is a contextual method allowing scientific description of the stakeholders, their needs and their organisational customs. Despite the recognition in the RE literature that ethnography could be helpful, the actual leverage of the method has been limited and ad hoc. To overcome the problems, we report in this paper a systematic mapping study where the relevant literature is examined. Building on the literature review, we further identify key parameters, their variations and their connections. The improved understanding about the role of ethnography in EIS RE is then presented in a consolidated model, and the guidelines of how to apply ethnography are organised by the key factors uncovered. Our study can direct researchers towards thorough understanding about the role that ethnography plays in EIS RE, and more importantly, to help practitioners better integrate contextually rich and ecologically valid methods in their daily practices.

Long-term Iron and Phosphorus Co-limitation Fundamentally Restructures Protein Biochemistry of High CO2-adapted Trichodesmium

NASA Astrophysics Data System (ADS)

Hutchins, D. A.; Walworth, N. G.; Fu, F.; Webb, E. A.; Saito, M. A.; Moran, D. M.; McIlvin, M.; Lee, M. D.

2016-02-01

Because the globally-distributed diazotrophic cyanobacterium Trichodesmium is a critical new-nitrogen source to nutrient-deplete marine ecosystems, it is crucial to understand its evolutionary responses to global-change factors as they interact with other important environmental controls such as iron and phosphorus limitation. We grew Trichodesmium under multiple iron and phosphorus (co)-limitation scenarios for 1 year following 7 years of adaptation to both present (380-ppm) and future (750-ppm) CO2 concentrations, and discovered a complex metabolic response specific to Fe/P co-limitation, which includes increased growth rates, whole-cell biochemical restructuring, and cell biomass reduction. The interaction of increasing CO2 with this nutrient co-limited state induced an additional set of comprehensive metabolic shifts away from those seen under present day CO2, characterized by upregulation of a new complement of proteins involved in broad cellular functions, core metabolism, and growth. This restructuring reveals a unique co-limited phenotype under Fe/P "balancing" co-limitation, which fundamentally alters traditional interpretations of interactive nutrient limitations and their subsequent controls on key global biogeochemical processes in both the present and future ocean.

Relations between water balance, wood traits and phenological behavior of tree species from a tropical dry forest in Costa Rica--a multifactorial study.

PubMed

Worbes, Martin; Blanchart, Sofie; Fichtler, Esther

2013-05-01

Drought tolerance is a key factor for the establishment and survival of tree species in tropical ecosystems. Specific mechanisms of drought resistance can be grouped into four functional ecotypes based on differences in leaf fall behavior: deciduous, brevi-deciduous, stem succulent and evergreen. To identify the key factors influencing phenology and cambial activity and thus drought tolerance, we tested the stomatal conductance, leaf water potential and stable carbon isotopes in the leaves and wood of 12 species from a tropical dry forest in Costa Rica. With wood anatomical techniques, we further studied seasonal cambial activity and a suite of wood traits related to water transport for each of the functional ecotypes. Using a principal component analysis, we identified two groups of variables that can be related to (i) hydraulic conductivity and (ii) control of transpiration and water loss. Hydraulic conductivity is controlled by vessel size as the limiting variable, water potential as the driving force and wood density as the stabilizing factor of the anatomical structure of an effective water transport system. Stomatal control plays a major role in terms of water loss or saving and is the dominant factor for differences in phenological behavior. Stem succulent species in particular developed a rarely identified but highly effective strategy against drought stress, which makes it a successful pioneer species in tropical dry forests.

Organizational and Teamwork Factors of Tele-Intensive Care Units.

PubMed

Wilkes, Michael S; Marcin, James P; Ritter, Lois A; Pruitt, Sherilyn

2016-09-01

Use of tele-intensive care involves organizational and teamwork factors across geographic locations. This situation adds to the complexity of collaboration in providing quality patient-centered care. To evaluate cross-agency teamwork of health care professionals caring for patients in tele-intensive care units in rural and urban regions. A national qualitative study was conducted in 3 US geographic regions with tele-intensive care programs. Discussions and interviews were held with key participants during site visits at 3 hub sites (specialist services location) and 8 rural spoke sites (patient location). The effects of communication and culture between the hub team and the spoke team on use of the services and effectiveness of care were evaluated. A total of 34 participants were interviewed. Specific organizational and teamwork factors significantly affect the functionality of a tele-intensive care unit. Key operational and cultural barriers that limit the benefits of the units include unrealistic expectations about operational capabilities, lack of trust, poorly defined leadership, and a lack of communication policies. Potential solutions include education on spoke facility resources, clearly defined expectations and role reversal education, team-building activities, and feedback mechanisms to share concerns, successes, and suggestions. Proper administration and attention to important cultural and teamwork factors are essential to making tele-intensive care units effective, practical, and sustainable. ©2016 American Association of Critical-Care Nurses.

Assistive technologies for self-managed pressure ulcer prevention in spinal cord injury: a scoping review.

PubMed

Tung, James Y; Stead, Brent; Mann, William; Ba'Pham; Popovic, Milos R

2015-01-01

Pressure ulcers (PUs) in individuals with spinal cord injury (SCI) present a persistent and costly problem. Continuing effort in developing new technologies that support self-managed care is an important prevention strategy. Specifically, the aims of this scoping review are to review the key concepts and factors related to self-managed prevention of PUs in individuals with SCI and appraise the technologies available to assist patients in self-management of PU prevention practices. There is broad consensus that sustaining long-term adherence to prevention regimens is a major concern. Recent literature highlights the interactions between behavioral and physiological risk factors. We identify four technology categories that support self-management: computer-based educational technologies demonstrated improved short-term gains in knowledge (2 studies), interface pressure mapping technologies demonstrated improved adherence to pressure-relief schedules up to 3 mo (5 studies), electrical stimulation confirmed improvements in tissue tolerance after 8 wk of training (3 studies), and telemedicine programs demonstrated improvements in independence and reduced hospital visits over 6 mo (2 studies). Overall, self-management technologies demonstrated low-to-moderate effectiveness in addressing a subset of risk factors. However, the effectiveness of technologies in preventing PUs is limited due to a lack of incidence reporting. In light of the key findings, we recommend developing integrated technologies that address multiple risk factors.

The relationship between employees' perceptions of safety and organizational culture.

PubMed

O'Toole, Michael

2002-01-01

With limited resources to help reduce occupational injuries, companies struggle with how to best focus these resources to achieve the greatest reduction in injuries for the optimal cost. Safety culture has been identified as a critical factor that sets the tone for importance of safety within an organization. An employee safety perception survey was conducted, and injury data were collected over a 45-month period from a large ready-mix concrete producer located in the southwest region of the United States. The results of this preliminary study suggest that the reductions in injuries experienced at the company locations was strongly impacted by the positive employee perceptions on several key factors. Management's commitment to safety was the factor with the greatest positive perception by employees taking the survey. This study was set up as a pilot project and did not unitize an experimental design. That weakness reduces the strength of these findings but adds to the importance of expanding the pilot project with an appropriate experimental design. Management leadership has been identified, along with several other factors, to influence employee perceptions of the safety management system. Those perceptions, in turn, appear to influence employee decisions that relate to at-risk behaviors and decisions on the job. The results suggest that employee perceptions of the safety system are related to management's commitment to safety, which, in turn, appear to be related to injury rates. Management should focus on how to best leverage these key factors to more positively impact injury rates within their companies.

What and how much do we eat? 24-hour dietary recall method.

PubMed

Salvador Castell, Gemma; Serra-Majem, Lluis; Ribas-Barba, Lourdes

2015-02-26

Diet, along with lifestyle factors, is an important determinant of the health status of an individual and of a community. Dietary assessment at the population level provides us with key information on the frequency and distribution of possible inadequate diets and/or nutritional status. It is also useful as input into the elaboration of food and nutrition policies aiming to improve dietary habits and the health status of a community. This article reviews the characteristics, advantages and limitations of the 24-hour dietary recall method (24hDR), which is one of the most widely used tools in nutrition epidemiology to identify food, energy and nutrient intake in national nutrition surveys, cross-sectional studies, clinical trials and cohort studies as well as in the evaluation of individual dietary intake and Total Diet assessment. To reduce the key factors associated with bias, the importance of previously trained interviewers is highlighted, as well as the role of support materials and the contribution of novel technologies. Copyright AULA MEDICA EDICIONES 2015. Published by AULA MEDICA. All rights reserved.

Sodium effects on mechanical performance and consideration in high temperature structural design for advanced reactors

NASA Astrophysics Data System (ADS)

Natesan, K.; Li, Meimei; Chopra, O. K.; Majumdar, S.

2009-07-01

Sodium environmental effects are key limiting factors in the high temperature structural design of advanced sodium-cooled reactors. A guideline is needed to incorporate environmental effects in the ASME design rules to improve the performance reliability over long operating times. This paper summarizes the influence of sodium exposure on mechanical performance of selected austenitic stainless and ferritic/martensitic steels. Focus is on Type 316SS and mod.9Cr-1Mo. The sodium effects were evaluated by comparing the mechanical properties data in air and sodium. Carburization and decarburization were found to be the key factors that determine the tensile and creep properties of the steels. A beneficial effect of sodium exposure on fatigue life was observed under fully reversed cyclic loading in both austenitic stainless steels and ferritic/martensitic steels. However, when hold time was applied during cyclic loading, the fatigue life was significantly reduced. Based on the mechanical performance of the steels in sodium, consideration of sodium effects in high temperature structural design of advanced fast reactors is discussed.

Nutrient/TOR-dependent regulation of RNA polymerase III controls tissue and organismal growth in Drosophila

PubMed Central

Marshall, Lynne; Rideout, Elizabeth J; Grewal, Savraj S

2012-01-01

The nutrient/target-of-rapamycin (TOR) pathway has emerged as a key regulator of tissue and organismal growth in metazoans. The signalling components of the nutrient/TOR pathway are well defined; however, the downstream effectors are less understood. Here, we show that the control of RNA polymerase (Pol) III-dependent transcription is an essential target of TOR in Drosophila. We find that TOR activity controls Pol III in growing larvae via inhibition of the repressor Maf1 and, in part, via the transcription factor Drosophila Myc (dMyc). Moreover, we show that loss of the Pol III factor, Brf, leads to reduced tissue and organismal growth and prevents TOR-induced cellular growth. TOR activity in the larval fat body, a tissue equivalent to vertebrate fat or liver, couples nutrition to insulin release from the brain. Accordingly, we find that fat-specific loss of Brf phenocopies nutrient limitation and TOR inhibition, leading to decreased systemic insulin signalling and reduced organismal growth. Thus, stimulation of Pol III is a key downstream effector of TOR in the control of cellular and systemic growth. PMID:22367393

A host basal transcription factor is a key component for infection of rice by TALE-carrying bacteria.

PubMed

Yuan, Meng; Ke, Yinggen; Huang, Renyan; Ma, Ling; Yang, Zeyu; Chu, Zhaohui; Xiao, Jinghua; Li, Xianghua; Wang, Shiping

2016-07-29

Transcription activator-like effectors (TALEs) are sequence-specific DNA binding proteins found in a range of plant pathogenic bacteria, where they play important roles in host-pathogen interactions. However, it has been unclear how TALEs, after they have been injected into the host cells, activate transcription of host genes required for infection success. Here, we show that the basal transcription factor IIA gamma subunit TFIIAγ5 from rice is a key component for infection by the TALE-carrying bacterium Xanthomonas oryzae pv. oryzae, the causal agent for bacterial blight. Direct interaction of several TALEs with TFIIAγ5 is required for activation of disease susceptibility genes. Conversely, reduced expression of the TFIIAγ5 host gene limits the induction of susceptibility genes and thus decreases bacterial blight symptoms. Suppression or mutation of TFIIAγ5 can also reduce bacterial streak, another devastating disease of rice caused by TALE-carrying X. oryzae pv. oryzicola. These results have important implications for formulating a widely applicable strategy with which to improve resistance of plants to TALE-carrying pathogens.

Androstenediol inhibits the trauma-hemorrhage-induced increase in caspase-3 by downregulating the inducible nitric oxide synthase pathway.

PubMed

Kiang, Juliann G; Peckham, Russell M; Duke, Leah E; Shimizu, Tomoharu; Chaudry, Irshad H; Tsokos, George C

2007-03-01

Soft tissue trauma and hemorrhage (T-H) diminishes various aspects of liver function, while it increases hepatic nitrate/nitrite, inducible nitric oxide synthase (iNOS), and endothelin-1 levels. Treatment with androstenediol (AED) inhibits the T-H-induced alterations of the above parameters. We sought to identify the molecular events underlying the beneficial effect of AED. Exposure of rats to T-H significantly increased the caspase-3 activity and protein, whereas treatment with AED significantly limited these increases. AED treatment also suppressed the T-H-induced increase in iNOS by effectively altering the levels of key transcription factors involved in the regulation of iNOS expression. Immunoprecipitation and immunoblotting analyses indicate that T-H increased apoptosome formation, and AED treatment significantly decreased it. Modulating the iNOS protein by transfecting cells with iNOS gene or small interfering RNA further confirmed the correlation between iNOS and caspase-3. Our data indicate that AED limits caspase-3 expression by suppressing the expression of transcription factors involved in the production of iNOS, resulting in decreased apoptosome. AED can potentially be a useful adjuvant for limiting liver apoptosis following T-H shock.

Understanding public responses to chemical, biological, radiological and nuclear incidents--driving factors, emerging themes and research gaps.

PubMed

Krieger, Kristian; Amlôt, Richard; Rogers, M Brooke

2014-11-01

This paper discusses the management of public responses to incidents involving chemical, biological, radiological and nuclear materials (CBRN). Given the extraordinary technical and operational challenges of a response to a CBRN release including, but not limited to, hazard detection and identification, casualty decontamination and multi-agency co-ordination, it is not surprising that public psychological and behavioural responses to such incidents have received limited attention by scholars and practitioners alike. As a result, a lack of understanding about the role of the public in effective emergency response constitutes a major gap in research and practice. This limitation must be addressed as a CBRN release has the potential to have wide-reaching psychological and behavioural impacts which, in turn, impact upon public morbidity and mortality rates. This paper addresses a number of key issues: why public responses matter; how responses have been conceptualised by practitioners; what factors have been identified as influencing public responses to a CBRN release and similar extreme events, and what further analysis is needed in order to generate a better understanding of public responses to inform the management of public responses to a CBRN release. Copyright © 2014 Elsevier Ltd. All rights reserved.

Risk and Protective Factors Associated with Health-Related Quality of Life Among Older Gay and Bisexual Men Living With HIV Disease

PubMed Central

Emlet, Charles A.

2013-01-01

Purpose: To identify risk and protective factors associated with mental and physical health-related quality of life, after controlling for key background characteristics, in a population of older gay and bisexual men living with HIV disease. Previous research examining quality of life among persons living with HIV rarely includes older adults. Design and Methods: Survey responses from 226 gay and bisexual men aged 50 and older, and living with HIV disease, which were part of the Caring and Aging with Pride study, were analyzed using multivariate linear regression models. Results: Findings reveal that comorbidity, limitations in activities, and victimization are significant risk factors for decreased physical and mental health-related quality of life. Stigma and HIV progression did not contribute to the overall outcome variables in multivariate models. Social support and self-efficacy serve as protective factors although social support was only significant with mental health-related quality of life. Implications: Comorbidity, functional limitations, and lifetime victimization are risks to quality of life among older gay and bisexual men with HIV disease. Self-efficacy and social support represent intrapersonal and interpersonal resources that can be enhanced through interventions to improve health-related quality of life. PMID:23355449

On the resolution of a MIEZE spectrometer

NASA Astrophysics Data System (ADS)

Martin, N.

2018-02-01

We study the effect of a finite sample size, beam divergence and detector thickness on the resolution function of a MIEZE spectrometer. We provide a transparent analytical framework which can be used to determine the optimal trade-off between incoming flux and time-resolution for a given experimental configuration. The key result of our approach is that the usual limiting factor of MIEZE spectroscopy, namely neutron path length differences throughout the instrument, can be suppressed up to relatively large momentum transfers by using a proper small-angle (SANS) geometry. Under such configuration, the hitherto accepted limits of MIEZE spectroscopy in terms of time-resolution are pushed upwards by typically an order of magnitude, giving access to most of the topical fields in soft- and hard-condensed matter physics.

Addressing the Educational Needs of Children with Williams Syndrome: A Rather Neglected Area of Research?

PubMed

Palikara, Olympia; Ashworth, Maria; Van Herwegen, Jo

2018-04-13

Williams syndrome (WS) is a rare neurodevelopmental disorder associated with physical health problems, limitations in cognitive abilities and increased risk of mental health difficulties. This profile of complex needs may make it challenging to support children with WS in schools. Surprisingly, in the current international move for inclusion, limited research exists on the educational provision and academic achievements of children with WS, including the non-existing literature on their voices and the perspectives of key stakeholders. This letter calls for additional research on the risk and protective factors associated with the educational outcomes of these children, the perspectives of the children themselves and the development of the evidence-base about the effectiveness of education intervention programs.

Using Large Diabetes Databases for Research.

PubMed

Wild, Sarah; Fischbacher, Colin; McKnight, John

2016-09-01

There are an increasing number of clinical, administrative and trial databases that can be used for research. These are particularly valuable if there are opportunities for linkage to other databases. This paper describes examples of the use of large diabetes databases for research. It reviews the advantages and disadvantages of using large diabetes databases for research and suggests solutions for some challenges. Large, high-quality databases offer potential sources of information for research at relatively low cost. Fundamental issues for using databases for research are the completeness of capture of cases within the population and time period of interest and accuracy of the diagnosis of diabetes and outcomes of interest. The extent to which people included in the database are representative should be considered if the database is not population based and there is the intention to extrapolate findings to the wider diabetes population. Information on key variables such as date of diagnosis or duration of diabetes may not be available at all, may be inaccurate or may contain a large amount of missing data. Information on key confounding factors is rarely available for the nondiabetic or general population limiting comparisons with the population of people with diabetes. However comparisons that allow for differences in distribution of important demographic factors may be feasible using data for the whole population or a matched cohort study design. In summary, diabetes databases can be used to address important research questions. Understanding the strengths and limitations of this approach is crucial to interpret the findings appropriately. © 2016 Diabetes Technology Society.

Crew interface analysis: Selected articles on space human factors research, 1987 - 1991

NASA Technical Reports Server (NTRS)

Bagian, Tandi (Compiler)

1993-01-01

As part of the Flight Crew Support Division at NASA, the Crew Interface Analysis Section is dedicated to the study of human factors in the manned space program. It assumes a specialized role that focuses on answering operational questions pertaining to NASA's Space Shuttle and Space Station Freedom Programs. One of the section's key contributions is to provide knowledge and information about human capabilities and limitations that promote optimal spacecraft and habitat design and use to enhance crew safety and productivity. The section provides human factors engineering for the ongoing missions as well as proposed missions that aim to put human settlements on the Moon and Mars. Research providing solutions to operational issues is the primary objective of the Crew Interface Analysis Section. The studies represent such subdisciplines as ergonomics, space habitability, man-computer interaction, and remote operator interaction.

Conflict resolution in insect societies.

PubMed

Ratnieks, Francis L W; Foster, Kevin R; Wenseleers, Tom

2006-01-01

Although best known for cooperation, insect societies also manifest many potential conflicts among individuals. These conflicts involve both direct reproduction by individuals and manipulation of the reproduction of colony members. Here we review five major areas of reproductive conflict in insect societies: (a) sex allocation, (b) queen rearing, (c) male rearing, (d) queen-worker caste fate, and (e) breeding conflicts among totipotent adults. For each area we discuss the basis for conflict (potential conflict), whether conflict is expressed (actual conflict), whose interests prevail (conflict outcome), and the factors that reduce colony-level costs of conflict (conflict resolution), such as factors that cause workers to work rather than to lay eggs. Reproductive conflicts are widespread, sometimes having dramatic effects on the colony. However, three key factors (kinship, coercion, and constraint) typically combine to limit the effects of reproductive conflict and often lead to complete resolution.

Highly parallel sparse Cholesky factorization

NASA Technical Reports Server (NTRS)

Gilbert, John R.; Schreiber, Robert

1990-01-01

Several fine grained parallel algorithms were developed and compared to compute the Cholesky factorization of a sparse matrix. The experimental implementations are on the Connection Machine, a distributed memory SIMD machine whose programming model conceptually supplies one processor per data element. In contrast to special purpose algorithms in which the matrix structure conforms to the connection structure of the machine, the focus is on matrices with arbitrary sparsity structure. The most promising algorithm is one whose inner loop performs several dense factorizations simultaneously on a 2-D grid of processors. Virtually any massively parallel dense factorization algorithm can be used as the key subroutine. The sparse code attains execution rates comparable to those of the dense subroutine. Although at present architectural limitations prevent the dense factorization from realizing its potential efficiency, it is concluded that a regular data parallel architecture can be used efficiently to solve arbitrarily structured sparse problems. A performance model is also presented and it is used to analyze the algorithms.

Environmental risk, social cognition, and drug use among young men who have sex with men: longitudinal effects of minority status on health processes and outcomes.

PubMed

Traube, Dorian E; Schrager, Sheree M; Holloway, Ian W; Weiss, George; Kipke, Michele D

2013-01-01

Young men who have sex with men (YMSM) continue to be at elevated risk for substance use; however, models explaining this phenomenon have often focused on a limited array of explanatory constructs. This study examined the longitudinal relationship of contextual risk factors, social cognitive processes, mental health, and health protective behavior to identify key mechanisms of illicit drug use of YMSM as they aged through emerging adulthood. Our sample included an ethnically diverse cohort of 487 YMSM recruited through venue based probability sampling in Los Angeles. We used latent growth curve modeling to understand relationships between environmental risk factors, changing individual and social process variables, health protective behavior, psychological distress, and illicit drug use outcomes among YMSM. Age, ethnicity, violence and discrimination, depression, and previous histories of illicit drug use were key elements of risk for future illicit drug use among YMSM. During this theoretically distinct time period, health as a value, self-efficacy, and social support are vital social cognitive processes for promoting self-change among YMSM, and YMSM have independent growth within each process. Health as a value, self-efficacy, and social support were dynamic social cognitive processes, which served as key mechanisms by which risk factors were converted into health promotion strategies or psychological distress, and ultimately illicit drug use. The efficacy of prevention interventions aimed at reducing illicit drug use among YMSM can be enhanced by addressing social cognitive processes for this underserved portion of the male population. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Environmental risk, social cognition, and drug use among young men who have sex with men: Longitudinal effects of minority status on health processes and outcomes

PubMed Central

Traube, Dorian E.; Schrager, Sheree M.; Holloway, Ian W.; Weiss, George; Kipke, Michele D.

2012-01-01

BACKGROUND Young men who have sex with men (YMSM) continue to be at elevated risk for substance use; however, models explaining this phenomenon have often focused on a limited array of explanatory constructs. This study examined the longitudinal relationship of contextual risk factors, social cognitive processes, mental health, and health protective behavior to identify key mechanisms of illicit drug use of YMSM as they aged through emerging adulthood. METHODS Our sample included an ethnically diverse cohort of 487 YMSM recruited through venue based probability sampling in Los Angeles. We used latent growth curve modeling to understand relationships between environmental risk factors, changing individual and social process variables, health protective behavior, psychological distress, and illicit drug use outcomes among YMSM. RESULTS Age, ethnicity, violence and discrimination, depression, and previous histories of illicit drug use were key elements of risk for future illicit drug use among YMSM. During this theoretically distinct time period, health as a value, self-efficacy, and social support are vital social cognitive processes for promoting self-change among YMSM, and YMSM have independent growth within each process. Health as a value, self-efficacy, and social support were dynamic social cognitive processes, which served as key mechanisms by which risk factors were converted into health promotion strategies or psychological distress, and ultimately illicit drug use. CONCLUSIONS The efficacy of prevention interventions aimed at reducing illicit drug use among YMSM can be enhanced by addressing social cognitive processes for this underserved portion of the male population. PMID:22749680

Examining the implementation of collaborative competencies in a critical care setting: Key challenges for enacting competency-based education.

PubMed

Goldman, Joanne; Kitto, Simon; Reeves, Scott

2017-11-21

Interprofessional collaboration is recognised as an important factor in improving patient care in intensive care units (ICUs). Competency frameworks, and more specifically interprofessional competency frameworks, are a key strategy being used to support the development of attitudes, knowledge, skills, and behaviours needed for an interprofessional approach to care. However, evidence for the application of competencies is limited. This study aimed to extend our empirically based understanding of the significance of interprofessional competencies to actual clinical practice in an ICU. An ethnographic approach was employed to obtain an in-depth insight into healthcare providers' perspectives, behaviours, and interactions of interprofessional collaboration in a medical surgical ICU in a community teaching hospital in Canada. Approximately 160 hours of observations were undertaken and 24 semi-structured interviews with healthcare workers were conducted over a period of 6 months. Data were analysed using a directed content approach where two national competency frameworks were used to help generate an understanding of the practice of interprofessional collaboration. Healthcare professionals demonstrated numerous instances of interprofessional communication, role understandings, and teamwork in the ICU setting, which supported a number of key collaborative competencies. However, organisational factors such as pressures for discharge and patient flow, staffing, and lack of prioritisation for interprofessional learning undermined competencies designed to improve collaboration and teamwork. The findings demonstrate that interprofessional competencies can play an important role in promoting knowledge, attitudes, skills, and behaviours needed. However, competencies that promote interprofessional collaboration are dependent on a range of contextual factors that enable (or impede) individuals to actually enact these competencies.

On the need of mode interpolation for data-driven Galerkin models of a transient flow around a sphere

NASA Astrophysics Data System (ADS)

Stankiewicz, Witold; Morzyński, Marek; Kotecki, Krzysztof; Noack, Bernd R.

2017-04-01

We present a low-dimensional Galerkin model with state-dependent modes capturing linear and nonlinear dynamics. Departure point is a direct numerical simulation of the three-dimensional incompressible flow around a sphere at Reynolds numbers 400. This solution starts near the unstable steady Navier-Stokes solution and converges to a periodic limit cycle. The investigated Galerkin models are based on the dynamic mode decomposition (DMD) and derive the dynamical system from first principles, the Navier-Stokes equations. A DMD model with training data from the initial linear transient fails to predict the limit cycle. Conversely, a model from limit-cycle data underpredicts the initial growth rate roughly by a factor 5. Key enablers for uniform accuracy throughout the transient are a continuous mode interpolation between both oscillatory fluctuations and the addition of a shift mode. This interpolated model is shown to capture both the transient growth of the oscillation and the limit cycle.

The relationship between anatomically correct electric and magnetic field dosimetry and publishe delectric and magnetic field exposure limits.

PubMed

Kavet, Robert; Dovan, Thanh; Reilly, J Patrick

2012-12-01

Electric and magnetic field exposure limits published by International Commission for Non-Ionizing Radiation Protection and Institute of Electrical and Electronics Engineers are aimed at protection against adverse electrostimulation, which may occur by direct coupling to excitable tissue and, in the case of electric fields, through indirect means associated with surface charge effects (e.g. hair vibration, skin sensations), spark discharge and contact current. For direct coupling, the basic restriction (BR) specifies the not-to-be-exceeded induced electric field. The key results of anatomically based electric and magnetic field dosimetry studies and the relevant characteristics of excitable tissue were first identified. This permitted us to assess the electric and magnetic field exposure levels that induce dose in tissue equal to the basic restrictions, and the relationships of those exposure levels to the limits now in effect. We identify scenarios in which direct coupling of electric fields to peripheral nerve could be a determining factor for electric field limits.

Dissemination of effective physical activity interventions: are we applying the evidence?

PubMed Central

Ballew, Paula; Brownson, Ross C.; Haire-Joshu, Debra; Heath, Gregory W.; Kreuter, Matthew W.

2010-01-01

Background. Given sparse knowledge on dissemination, this study sought to explore key benefits, barriers and contextual factors that are perceived to be important to the adoption and implementation of the ‘Community Guide's’ evidence-based physical activity recommendations. Design. We conducted case studies in two states where extensive adoption and implementation of the Guide's recommendations have occurred and in two states where widespread dissemination has lagged. Interviews (n = 76) were semi-structured and included both quantitative and qualitative methods. Participant perceptions from the following areas were examined: (i) priority of physical activity, (ii) awareness of and ability to define the term ‘evidence-based approaches’ and (iii) awareness, adoption, facilitators, benefits, challenges and barriers to Guide adoption. Results. Key enabling factors among high capacity states included: funds and direction from the Centers for Disease Control and Prevention; leadership support; capable staff; and successful partnerships and collaborations. Restraining forces among low capacity states included: the Guide recommendations being too new; participants being too new to current job; lack of time and training on how to use the Guide recommendations; limited funds and other resources and lack of leadership. Conclusion. To be effective, we must gain an understanding of contextual factors when designing for dissemination. PMID:20156839

Citizen science participation in research in the environmental sciences: key factors related to projects' success and longevity.

PubMed

Cunha, Davi G F; Marques, Jonatas F; Resende, Juliana C DE; Falco, Patrícia B DE; Souza, Chrislaine M DE; Loiselle, Steven A

2017-01-01

The potential impacts of citizen science initiatives are increasing across the globe, albeit in an imbalanced manner. In general, there is a strong element of trial and error in most projects, and the comparison of best practices and project structure between different initiatives remains difficult. In Brazil, the participation of volunteers in environmental research is limited. Identifying the factors related to citizen science projects' success and longevity within a global perspective can contribute for consolidating such practices in the country. In this study, we explore past and present projects, including a case study in Brazil, to identify the spatial and temporal trends of citizen science programs as well as their best practices and challenges. We performed a bibliographic search using Google Scholar and considered results from 2005-2014. Although these results are subjective due to the Google Scholar's algorithm and ranking criteria, we highlighted factors to compare projects across geographical and disciplinary areas and identified key matches between project proponents and participants, project goals and local priorities, participant profiles and engagement, scientific methods and funding. This approach is a useful starting point for future citizen science projects, allowing for a systematic analysis of potential inconsistencies and shortcomings in this emerging field.

Seroprevalence of Burkholderia pseudomallei among Adults in Coastal Areas in Southwestern India

PubMed Central

Vandana, Kalwaje Eshwara; Mukhopadhyay, Chiranjay; Tellapragada, Chaitanya; Kamath, Asha; Tipre, Meghan; Bhat, Vinod; Sathiakumar, Nalini

2016-01-01

Background Although melioidosis, is an important disease in many Southeast Asian countries and Australia, there is limited data on its prevalence and disease burden in India. However, an increase in case reports of melioidosis in recent years indicates its endemicity in India. Aims and methods A population-based cross-sectional seroprevalence study was undertaken to determine the seroprevalence of B. pseudomallei by indirect haemagglutination assay and to investigate the associated risk determinants. Subjects were 711 adults aged 18 to 65 years residing in Udupi district, located in south-western coast of India. Key results Overall, 29% of the study subjects were seropositive (titer ≥20). Females were twice as likely to be seropositive compared to males. Rates of seroprevalence were similar in farmers and non-farmers. Besides gardening, other factors including socio-demographic, occupational and environmental factors did not show any relationship with seropositive status. Major conclusions There is a serological evidence of exposure to B. pseudomallei among adults in India. While the bacterium inhabits soil, exposure to the agent is not limited to farmers. Non-occupational exposure might play an important role in eliciting antibody response to the bacterium and may also be an important factor in disease causation. PMID:27078156

An Anti-Inflammatory Role of VEGFR2/Src Kinase Inhibitor in Herpes Simplex Virus 1-Induced Immunopathology▿

PubMed Central

Sharma, Shalini; Mulik, Sachin; Kumar, Naveen; Suryawanshi, Amol; Rouse, Barry T.

2011-01-01

Corneal neovascularization represents a key step in the blinding inflammatory stromal keratitis (SK) lesion caused by ocular infection with herpes simplex virus (HSV). In this report, we describe a novel approach for limiting the angiogenesis caused by HSV infection of the mouse eye. We show that topical or systemic administration of the Src kinase inhibitor (TG100572) that inhibits downstream molecules involved in the vascular endothelial growth factor (VEGF) signaling pathway resulted in markedly diminished levels of HSV-induced angiogenesis and significantly reduced the severity of SK lesions. Multiple mechanisms were involved in the inhibitory effects. These included blockade of IL-8/CXCL1 involved in inflammatory cells recruitment that are a source of VEGF, diminished cellular infiltration in the cornea, and reduced proliferation and migration of CD4+ T cells into the corneas. As multiple angiogenic factors (VEGF and basic fibroblast growth factor [bFGF]) play a role in promoting angiogenesis during SK and since Src kinases are involved in signaling by many of them, the use of Src kinase inhibition represents a promising way of limiting the severity of SK lesions the most common cause of infectious blindness in the Western world. PMID:21471229

Using portable particle sizing instrumentation to rapidly measure the penetration of fine and ultrafine particles in unoccupied residences.

PubMed

Zhao, H; Stephens, B

2017-01-01

Much of human exposure to particulate matter of outdoor origin occurs inside buildings, particularly in residences. The particle penetration factor through leaks in a building's exterior enclosure assembly is a key parameter that governs the infiltration of outdoor particles. However, experimental data for size-resolved particle penetration factors in real buildings, as well as penetration factors for fine particles less than 2.5 μm (PM 2.5 ) and ultrafine particles less than 100 nm (UFPs), remain limited, in part because of previous limitations in instrumentation and experimental methods. Here, we report on the development and application of a modified test method that utilizes portable particle sizing instrumentation to measure size-resolved infiltration factors and envelope penetration factors for 0.01-2.5 μm particles, which are then used to estimate penetration factors for integral measures of UFPs and PM 2.5 . Eleven replicate measurements were made in an unoccupied apartment unit in Chicago, IL to evaluate the accuracy and repeatability of the test procedure and solution methods. Mean estimates of size-resolved penetration factors ranged from 0.41 ± 0.14 to 0.73 ± 0.05 across the range of measured particle sizes, while mean estimates of penetration factors for integral measures of UFPs and PM 2.5 were 0.67 ± 0.05 and 0.73 ± 0.05, respectively. Average relative uncertainties for all particle sizes/classes were less than 20%. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Contributory factors in surgical incidents as delineated by a confidential reporting system.

PubMed

Mushtaq, F; O'Driscoll, C; Smith, Fct; Wilkins, D; Kapur, N; Lawton, R

2018-05-01

Background Confidential reporting systems play a key role in capturing information about adverse surgical events. However, the value of these systems is limited if the reports that are generated are not subjected to systematic analysis. The aim of this study was to provide the first systematic analysis of data from a novel surgical confidential reporting system to delineate contributory factors in surgical incidents and document lessons that can be learned. Methods One-hundred and forty-five patient safety incidents submitted to the UK Confidential Reporting System for Surgery over a 10-year period were analysed using an adapted version of the empirically-grounded Yorkshire Contributory Factors Framework. Results The most common factors identified as contributing to reported surgical incidents were cognitive limitations (30.09%), communication failures (16.11%) and a lack of adherence to established policies and procedures (8.81%). The analysis also revealed that adverse events were only rarely related to an isolated, single factor (20.71%) - with the majority of cases involving multiple contributory factors (79.29% of all cases had more than one contributory factor). Examination of active failures - those closest in time and space to the adverse event - pointed to frequent coupling with latent, systems-related contributory factors. Conclusions Specific patterns of errors often underlie surgical adverse events and may therefore be amenable to targeted intervention, including particular forms of training. The findings in this paper confirm the view that surgical errors tend to be multi-factorial in nature, which also necessitates a multi-disciplinary and system-wide approach to bringing about improvements.

Current-limiting challenges for all-spin logic devices

PubMed Central

Su, Li; Zhang, Youguang; Klein, Jacques-Olivier; Zhang, Yue; Bournel, Arnaud; Fert, Albert; Zhao, Weisheng

2015-01-01

All-spin logic device (ASLD) has attracted increasing interests as one of the most promising post-CMOS device candidates, thanks to its low power, non-volatility and logic-in-memory structure. Here we investigate the key current-limiting factors and develop a physics-based model of ASLD through nano-magnet switching, the spin transport properties and the breakdown characteristic of channel. First, ASLD with perpendicular magnetic anisotropy (PMA) nano-magnet is proposed to reduce the critical current (Ic0). Most important, the spin transport efficiency can be enhanced by analyzing the device structure, dimension, contact resistance as well as material parameters. Furthermore, breakdown current density (JBR) of spin channel is studied for the upper current limitation. As a result, we can deduce current-limiting conditions and estimate energy dissipation. Based on the model, we demonstrate ASLD with different structures and channel materials (graphene and copper). Asymmetric structure is found to be the optimal option for current limitations. Copper channel outperforms graphene in term of energy but seriously suffers from breakdown current limit. By exploring the current limit and performance tradeoffs, the optimization of ASLD is also discussed. This benchmarking model of ASLD opens up new prospects for design and implementation of future spintronics applications. PMID:26449410

SCOR based key success factors in cooking oil supply chain buyers perspective in Padang City

NASA Astrophysics Data System (ADS)

Zahara, Fatimah; Hadiguna, Rika Ampuh

2017-11-01

Supply chain of cooking oil is a network of companies from palm oil as raw material to retailers which work to create the value and deliver products into the end consumers. This paper is aimed to study key success factors based on consumer's perspective as the last stage in the supply chain. Consumers who are examined in this study are restaurants management or owners. Restaurant is the biggest consumption of cooking oil. The factors is studied based on Supply Chain Operation Reference (SCOR) version 10.0. Factors used are formulated based on the third-level metrics of SCOR Model. Factors are analyzed using factors analysis. This study found factors which become key success factors in managing supply chain of cooking oil encompass reliability, responsiveness and agility. Key success factors can be applied by governments as policy making and cooking oil companies as formulation of the distribution strategies.

Elucidating Key Motifs Required for Arp2/3-Dependent and Independent Actin Nucleation by Las17/WASP

PubMed Central

Urbanek, Agnieszka N.; Smaczynska-de Rooij, Iwona I.

2016-01-01

Actin nucleation is the key rate limiting step in the process of actin polymerization, and tight regulation of this process is critical to ensure actin filaments form only at specific times and at defined regions of the cell. Arp2/3 is a well-characterised protein complex that can promote nucleation of new filaments, though its activity requires additional nucleation promotion factors (NPFs). The best recognized of these factors are the WASP family of proteins that contain binding motifs for both monomeric actin and for Arp2/3. Previously we demonstrated that the yeast WASP homologue, Las17, in addition to activating Arp2/3 can also nucleate actin filaments de novo, independently of Arp2/3. This activity is dependent on its polyproline rich region. Through biochemical and in vivo analysis we have now identified key motifs within the polyproline region that are required for nucleation and elongation of actin filaments, and have addressed the role of the WH2 domain in the context of actin nucleation without Arp2/3. We have also demonstrated that full length Las17 is able to bind liposomes giving rise to the possibility of direct linkage of nascent actin filaments to specific membrane sites to which Las17 has been recruited. Overall, we propose that Las17 functions as the key initiator of de novo actin filament formation at endocytic sites by nucleating, elongating and tethering nascent filaments which then serve as a platform for Arp2/3 recruitment and function. PMID:27637067

Gene-to-metabolite network for biosynthesis of lignans in MeJA-elicited Isatis indigotica hairy root cultures

PubMed Central

Chen, Ruibing; Li, Qing; Tan, Hexin; Chen, Junfeng; Xiao, Ying; Ma, Ruifang; Gao, Shouhong; Zerbe, Philipp; Chen, Wansheng; Zhang, Lei

2015-01-01

Root and leaf tissue of Isatis indigotica shows notable anti-viral efficacy, and are widely used as “Banlangen” and “Daqingye” in traditional Chinese medicine. The plants' pharmacological activity is attributed to phenylpropanoids, especially a group of lignan metabolites. However, the biosynthesis of lignans in I. indigotica remains opaque. This study describes the discovery and analysis of biosynthetic genes and AP2/ERF-type transcription factors involved in lignan biosynthesis in I. indigotica. MeJA treatment revealed differential expression of three genes involved in phenylpropanoid backbone biosynthesis (IiPAL, IiC4H, Ii4CL), five genes involved in lignan biosynthesis (IiCAD, IiC3H, IiCCR, IiDIR, and IiPLR), and 112 putative AP2/ERF transcription factors. In addition, four intermediates of lariciresinol biosynthesis were found to be induced. Based on these results, a canonical correlation analysis using Pearson's correlation coefficient was performed to construct gene-to-metabolite networks and identify putative key genes and rate-limiting reactions in lignan biosynthesis. Over-expression of IiC3H, identified as a key pathway gene, was used for metabolic engineering of I. indigotica hairy roots, and resulted in an increase in lariciresinol production. These findings illustrate the utility of canonical correlation analysis for the discovery and metabolic engineering of key metabolic genes in plants. PMID:26579184

Diffusional conductance to CO2 is the key limitation to photosynthesis in salt-stressed leaves of rice (Oryza sativa).

PubMed

Wang, Xiaoxiao; Wang, Wencheng; Huang, Jianliang; Peng, Shaobing; Xiong, Dongliang

2018-05-01

Salinity significantly limits leaf photosynthesis but the factors causing the limitation in salt-stressed leaves remain unclear. In the present work, photosynthetic and biochemical traits were investigated in four rice genotypes under two NaCl concentration (0 and 150 mM) to assess the stomatal, mesophyll and biochemical contributions to reduced photosynthetic rate (A) in salt-stressed leaves. Our results indicated that salinity led to a decrease in A, leaf osmotic potential, electron transport rate and CO 2 concentrations in the chloroplasts (C c ) of rice leaves. Decreased A in salt-stressed leaves was mainly attributable to low C c , which was determined by stomatal and mesophyll conductance. The increased stomatal limitation was mainly related to the low leaf osmotic potential caused by soil salinity. However, the increased mesophyll limitation in salt-stressed leaves was related to both osmotic stress and ion stress. These findings highlight the importance of considering mesophyll conductance when developing salinity-tolerant rice cultivars. © 2017 Scandinavian Plant Physiology Society.

Evaluation of the impact of frost resistances on potential altitudinal limit of trees.

PubMed

Charrier, Guillaume; Cochard, Hervé; Améglio, Thierry

2013-09-01

Winter physiology of woody plants is a key issue in temperate biomes. Here, we investigated different frost resistance mechanisms on 1-year-old branches of 11 European tree species from November until budburst: (i) frost hardiness of living cells (by electrolyte leakage method), (ii) winter embolism sensitivity (by percentage loss of conductivity: PLC) and (iii) phenological variation of budburst (by thermal time to budburst). These ecophysiological traits were analyzed according to the potential altitudinal limit, which is highly related to frost exposure. Seasonal frost hardiness and PLC changes are relatively different across species. Maximal PLC observed in winter (PLCMax) was the factor most closely related to potential altitudinal limit. Moreover, PLCMax was related to the mean hydraulic diameter of vessels (indicating embolism sensitivity) and to osmotic compounds (indicating ability of living cells to refill xylem conducting elements). Winter embolism formation seems to be counterbalanced by active refilling from living cells. These results enabled us to model potential altitudinal limit according to three of the physiological/anatomical parameters studied. Monitoring different frost resistance strategies brings new insights to our understanding of the altitudinal limits of trees.

Aerodynamic Performance of a Compact, High Work-Factor Centrifugal Compressor at the Stage and Subcomponent Level

NASA Technical Reports Server (NTRS)

Braunscheidel, Edward P.; Welch, Gerard E.; Skoch, Gary J.; Medic, Gorazd; Sharma, Om P.

2015-01-01

The measured aerodynamic performance of a compact, high work-factor, single-stage centrifugal compressor, comprising an impeller, diffuser, 90deg-bend, and exit guide vane is reported. Performance levels are based on steady-state total-pressure and total-temperature rake and angularity-probe data acquired at key machine rating planes during recent testing at NASA Glenn Research Center. Aerodynamic performance at the stage level is reported for operation between 70 to 105 percent of design corrected speed, with subcomponent (impeller, diffuser, and exit-guide-vane) flow field measurements presented and discussed at the 100 percent design-speed condition. Individual component losses from measurements are compared with pre-test CFD predictions on a limited basis.

The Cyber Security Crisis

ScienceCinema

Spafford, Eugene

2018-05-11

Despite considerable activity and attention, the overall state of information security continues to get worse. Attacks are increasing, fraud and theft are rising, and losses may exceed $100 billion per year worldwide. Many factors contribute to this, including misplaced incentives for industry, a lack of attention by government, ineffective law enforcement, and an uninformed image of who the perpetrators really are. As a result, many of the intended attempts at solutions are of limited (if any) overall effectiveness. This presentation will illustrate some key aspects of the cyber security problem and its magnitude, as well as provide some insight into causes and enabling factors. The talk will conclude with some observations on how the computing community can help improve the situation, as well as some suggestions for 'cyber self-defense.'

Aerodynamic Performance of a Compact, High Work-Factor Centrifugal Compressor at the Stage and Subcomponent Level

NASA Technical Reports Server (NTRS)

Braunscheidel, Edward P.; Welch, Gerard E.; Skoch, Gary J.; Medic, Gorazd; Sharma, Om P.

2014-01-01

The measured aerodynamic performance of a compact, high work-factor, single-stage centrifugal compressor, comprising an impeller, diffuser, 90º-bend, and exit guide vane is reported. Performance levels are based on steady-state total-pressure and total-temperature rake and angularity-probe data acquired at key machine rating planes during recent testing at NASA Glenn Research Center. Aerodynamic performance at the stage level is reported for operation between 70 to 105% of design corrected speed, with subcomponent (impeller, diffuser, and exit-guide-vane) flow field measurements presented and discussed at the 100% design-speed condition. Individual component losses from measurements are compared with pre-test CFD predictions on a limited basis.

Providing Continuity of Care for Chronic Diseases in the Aftermath of Katrina: From Field Experience to Policy Recommendations

PubMed Central

Arrieta, Martha I.; Foreman, Rachel D.; Crook, Errol D.; Icenogle, Marjorie L.

2014-01-01

This study sought to elicit challenges and solutions in the provision of health care to those with chronic diseases after Hurricane Katrina in coastal Alabama and Mississippi. In-depth interviews with 30 health and social service providers (key informants) and 4 focus groups with patients with chronic diseases were conducted. Subsequently an advisory panel of key informants was convened. Findings were summarized and key informants submitted additional feedback. The chronic diseases identified as medical management priorities by key informants were mental health, diabetes mellitus, hypertension, respiratory illness, end-stage renal disease, cardiovascular disease, and cancer. The most frequently mentioned barrier to providing care was maintaining continuity of medications. Contributing factors were inadequate information (inaccessible medical records, poor patient knowledge) and financial constraints. Implemented or suggested solutions included relaxation of insurance limitations preventing advance prescription refills; better predisaster patient education to improve medical knowledge; promotion of personal health records; support for information technology systems at community health centers, in particular electronic medical records; improved allocation of donated medications/medical supplies (centralized coordination, decentralized distribution); and networking between local responders and external aid. PMID:19865042

76 FR 24024 - Request for Information Relating to Studies Regarding the Resolution of Financial Companies Under...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-29

... such adverse impacts without creating such moral hazard; (D) The key factors and considerations that... financial companies; (A) The key factors and considerations that should be taken into account in assessing... of systemic financial companies; (B) The key factors and considerations that should be taken into...

Implementing an interprofessional first-year teamwork project: some key reflections.

PubMed

McNaughton, Susan Maree

2013-09-01

Implementing an interprofessional teamwork project for first-year students presents pedagogical and practical challenges. While transferable skills and attributes are important, engagement of students with limited professional experience in teamwork depends on relevance to current learning needs. This report outlines principles learned from planning and implementing a teamwork project for an interprofessional health administration and service development course. Practising interprofessional teamwork as leaders and teachers, aligning with previous, current and future teamwork content and processes and responding to student feedback and achievement have been the key factors in shaping the project over three semesters. Face-to-face and online interprofessional teamwork learning has necessitated developing resources that support self-direction, using familiar technology and providing enabling physical environments. Implications for first-year interprofessional teamwork are that structured well-resourced processes, responsiveness and alignment of learning all improve student outcomes.

The Multiple Origins of Complex Multicellularity

NASA Astrophysics Data System (ADS)

Knoll, Andrew H.

2011-05-01

Simple multicellularity has evolved numerous times within the Eukarya, but complex multicellular organisms belong to only six clades: animals, embryophytic land plants, florideophyte red algae, laminarialean brown algae, and two groups of fungi. Phylogeny and genomics suggest a generalized trajectory for the evolution of complex multicellularity, beginning with the co-optation of existing genes for adhesion. Molecular channels to facilitate cell-cell transfer of nutrients and signaling molecules appear to be critical, as this trait occurs in all complex multicellular organisms but few others. Proliferation of gene families for transcription factors and cell signals accompany the key functional innovation of complex multicellular clades: differentiated cells and tissues for the bulk transport of oxygen, nutrients, and molecular signals that enable organisms to circumvent the physical limitations of diffusion. The fossil records of animals and plants document key stages of this trajectory.

The influence of actor capacities on EIA system performance in low and middle income countries —Cases from Georgia and Ghana

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

Kolhoff, Arend J., E-mail: akolhoff@eia.nl; Runhaar, Hens A.C., E-mail: H.A.C.Runhaar@uu.nl; Forest and Nature Conservation Policy Group, Wageningen University and Research Centre, Wageningen

In this paper, we aim to better understand the factors that contribute to the substantive performance of EIA systems in low and middle income countries. Substantive performance is defined as the extent to which the EIA process contributes to the EIA objectives for the long term, namely environmental protection or, even more ambitious, sustainable development. We have therefore developed a conceptual model in which we focus on the key actors in the EIA system, the proponent and the EIA authority and their level of ownership as a key capacity to measure their performance, and we distinguish procedural performance and somemore » contextual factors. This conceptual model is then verified and refined for the EIA phase and the EIA follow-up phase (permitting, monitoring and enforcement) by means of 12 case studies from Ghana (four cases) and Georgia (eight cases), both lower–middle income countries. We observe that in most cases the level of substantive performance increases during the EIA phase but drops during the EIA follow-up phase, and as a result only five out of 12 operational cases are in compliance with permit conditions or national environmental standards. We conclude, firstly that ownership of the proponent is the most important factor explaining the level of substantive performance; the higher the proponent's level of ownership the higher the level of substantive performance. The influence of the EIA authority on substantive performance is limited. Secondly, the influence of procedural performance on substantive performance seems less important than expected in the EIA phase but more important during the EIA follow-up phase. In order to improve substantive performance we learned two lessons. Firstly, increasing the proponent's level of ownership seems obvious, but direct change is probably difficult. However, where international finance institutes are involved they can increase ownership. Despite the limited influence of the EIA authority, a proactive strategy of, for example, working together with international finance institutes has a slightly larger influence than a reactive strategy. - Highlights: • Ownership of the proponent is the most important factor explaining the level of substantive performance. • The influence of the EIA authority on substantive performance is limited. • The influence of procedural performance on substantive performance seems less important than expected in the EIA phase but more important during the EIA follow-up phase.« less

WRKY Transcription Factors: Key Components in Abscisic Acid Signaling

DTIC Science & Technology

2011-01-01

Review article WRKY transcription factors : key components in abscisic acid signalling Deena L. Rushton1, Prateek Tripathi1, Roel C. Rabara1, Jun Lin1...May 2011. *Correspondence (Tel +605 688 5749; fax +605 688 5624; email paul.rushton@sdstate.edu) Keywords: abscisic acid, WRKY transcription factor ...seed germination, drought, abiotic stress. Summary WRKY transcription factors (TFs) are key regulators of many plant processes, including the responses

OCCUPATIONAL SAFETY AND HEALTH EDUCATION AND TRAINING FOR UNDERSERVED POPULATIONS

PubMed Central

O’CONNOR, TOM; FLYNN, MICHAEL; WEINSTOCK, DEBORAH; ZANONI, JOSEPH

2015-01-01

This article presents an analysis of the essential elements of effective occupational safety and health education and training programs targeting under-served communities. While not an exhaustive review of the literature on occupational safety and health training, the paper provides a guide for practitioners and researchers to the key factors they should consider in the design and implementation of training programs for underserved communities. It also addresses issues of evaluation of such programs, with specific emphasis on considerations for programs involving low-literacy and limited-English-speaking workers. PMID:25053607

Key trends in environmental advertising across 30 years in National Geographic magazine.

PubMed

Ahern, Lee; Bortree, Denise Sevick; Smith, Alexandra Nutter

2013-05-01

This longitudinal retrospective case study describes the sponsors, ad types, frames and message factors in green advertising over three decades in National Geographic magazine, the bellwether nature publication in the USA. In addition to providing a clearer picture of the extent and nature of environmental strategic messaging over three decades, results provide empirical support for theoretical relationships between the level of green advertising and economic indicators. After providing historical and theoretical context, detailed results are presented for both overall and longitudinal analysis. Limitations and implications for future research are discussed.

Biocidal treatment and preservation of liquid fuels

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

Siegert, W.

1995-05-01

Strict microbiological limit values are the result of damage caused by microorganisms in fuels. With MAR 71, a biocide based on methylenebisoxazolidine, a product is available which has been tested and approved by leading car manufacturers, the mineral oil industry, and NATO. Depending on the degree of microbiological contamination, different decontamination concepts are presented, and recommendations for the treatment of fuels which are contaminated when purchased are given. In order to avoid recontamination, planning principles or the new design of tanks are necessary. The possibility of convenient, economical and regular drainage is a key factor.

Energy use, entropy and extra-terrestrial civilizations

NASA Astrophysics Data System (ADS)

Hetesi, Zsolt

2010-03-01

The possible number of extra-terrestrial civilizations is estimated by the Drake-equation. Many articles pointed out that there are missing factors and over-estimations in the original equation. In this article we will point out that assuming some axioms there might be several limits for a technical civilization. The key role of the energy use and the problem of the centres and periphery strongly influence the value of the Llifetime of a civilization. Our development have several edifications of the investigations of the growth of an alien civilization.

Occupational safety and health education and training for underserved populations.

PubMed

O'Connor, Tom; Flynn, Michael; Weinstock, Deborah; Zanoni, Joseph

2014-01-01

This article presents an analysis of the essential elements of effective occupational safety and health education and training programs targeting underserved communities. While not an exhaustive review of the literature on occupational safety and health training, the paper provides a guide for practitioners and researchers to the key factors they should consider in the design and implementation of training programs for underserved communities. It also addresses issues of evaluation of such programs, with specific emphasis on considerations for programs involving low-literacy and limited-English-speaking workers.

Multifunctional biocompatible coatings on magnetic nanoparticles

NASA Astrophysics Data System (ADS)

Bychkova, A. V.; Sorokina, O. N.; Rosenfeld, M. A.; Kovarski, A. L.

2012-11-01

Methods for coating formation on magnetic nanoparticles used in biology and medicine are considered. Key requirements to the coatings are formulated, namely, biocompatibility, stability, the possibility of attachment of pharmaceutical agents, and the absence of toxicity. The behaviour of nanoparticle/coating nanosystems in the body including penetration through cellular membranes and the excretion rates and routes is analyzed. Parameters characterizing the magnetic properties of these systems and their magnetic controllability are described. Factors limiting the applications of magnetically controlled nanosystems for targeted drug delivery are discussed. The bibliography includes 405 references.

Comparative quantification of health risks: Conceptual framework and methodological issues

PubMed Central

Murray, Christopher JL; Ezzati, Majid; Lopez, Alan D; Rodgers, Anthony; Vander Hoorn, Stephen

2003-01-01

Reliable and comparable analysis of risks to health is key for preventing disease and injury. Causal attribution of morbidity and mortality to risk factors has traditionally been conducted in the context of methodological traditions of individual risk factors, often in a limited number of settings, restricting comparability. In this paper, we discuss the conceptual and methodological issues for quantifying the population health effects of individual or groups of risk factors in various levels of causality using knowledge from different scientific disciplines. The issues include: comparing the burden of disease due to the observed exposure distribution in a population with the burden from a hypothetical distribution or series of distributions, rather than a single reference level such as non-exposed; considering the multiple stages in the causal network of interactions among risk factor(s) and disease outcome to allow making inferences about some combinations of risk factors for which epidemiological studies have not been conducted, including the joint effects of multiple risk factors; calculating the health loss due to risk factor(s) as a time-indexed "stream" of disease burden due to a time-indexed "stream" of exposure, including consideration of discounting; and the sources of uncertainty. PMID:12780936

Work limitations, workplace concerns, and job satisfaction of persons with chronic disease.

PubMed

Siu, Andrew M H; Hung, Anchor; Lam, Ada Y L; Cheng, Andy

2013-01-01

This study investigates the workplace experiences of people with chronic diseases, including their work limitations, emotional health, concerns about discrimination, and support from colleagues and employer. This study identifies the factors that contribute to work adjustment (job tenure and job satisfaction). A purposive sample of 136 persons aged 18 to 60 with chronic diseases who had been employed in the past 6 months completed a survey about their workplace experience. The questionnaire included several standardized instruments: the Perceived Health and Self-efficacy in Managing Chronic Disease Scale, Work Limitations Questionnaire, Overall Job Satisfaction Scale, and the Depression Anxiety Stress Scale-21. The researchers also designed original items to measure concerns about discriminatory practices, workplace support, and self-stigma. Persons with chronic diseases were fairly satisfied with their jobs and had extended stays in those jobs. They reported a minor productivity loss and physical limitations. Most participants let co-workers, employers, and supervisors know they had chronic disease, but they were concerned about the support those people provide. Participants were more likely to be highly satisfied with their jobs if they had high self-efficacy in managing their disease, perceived more workplace support, and had less work limitations (especially output demands). Job tenure is associated age, education, and monthly income, but not clinical indicators. Persons with chronic disease who were able to maintain good work adjustment tended to be "fit" with few work limitations and little emotional distress. The key factors affecting work adjustment were efficacy in managing their disease, workplace support, and output demands.

"You can save time if…"-A qualitative study on internal factors slowing down clinical trials in Sub-Saharan Africa.

PubMed

Vischer, Nerina; Pfeiffer, Constanze; Limacher, Manuela; Burri, Christian

2017-01-01

The costs, complexity, legal requirements and number of amendments associated with clinical trials are rising constantly, which negatively affects the efficient conduct of trials. In Sub-Saharan Africa, this situation is exacerbated by capacity and funding limitations, which further increase the workload of clinical trialists. At the same time, trials are critically important for improving public health in these settings. The aim of this study was to identify the internal factors that slow down clinical trials in Sub-Saharan Africa. Here, factors are limited to those that exclusively relate to clinical trial teams and sponsors. These factors may be influenced independently of external conditions and may significantly increase trial efficiency if addressed by the respective teams. We conducted sixty key informant interviews with clinical trial staff working in different positions in two clinical research centres in Kenya, Ghana, Burkina Faso and Senegal. The study covered English- and French-speaking, and Eastern and Western parts of Sub-Saharan Africa. We performed thematic analysis of the interview transcripts. We found various internal factors associated with slowing down clinical trials; these were summarised into two broad themes, "planning" and "site organisation". These themes were consistently mentioned across positions and countries. "Planning" factors related to budget feasibility, clear project ideas, realistic deadlines, understanding of trial processes, adaptation to the local context and involvement of site staff in planning. "Site organisation" factors covered staff turnover, employment conditions, career paths, workload, delegation and management. We found that internal factors slowing down clinical trials are of high importance to trial staff. Our data suggest that adequate and coherent planning, careful assessment of the setting, clear task allocation and management capacity strengthening may help to overcome the identified internal factors and allow clinical trials to proceed more efficiently.

CZTSSe: Materials and Physics Challenges

NASA Astrophysics Data System (ADS)

Gunawan, Oki

2011-03-01

Thin-film photovoltaic (PV) technologies led by CdTe and Cu(In,Ga) Se 2 (CIGS) are enjoying growing market share, due to their high performance and cost competitiveness, in the quest for renewable energy for the future. However the reliance on non-earth abundant elements tellurium and indium in these technologies presents a potential obstacle to ultimate terawatt deployment. We recently demonstrated kesterite Cu 2 ZnSn(Se,S)4 (CZTSSe) solar cells, comprised of the earth abundant metals copper, zinc and tin, with world record efficiency of 9.7%. In this talk we present a comprehensive device characterization study that pinpoints the key performance bottlenecks in these cells. We find strong buffer-absorber interface recombination and low minority carrier lifetimes that limit the open circuit voltage and a high and diverging device series resistance at lower temperature that suggests a blocking back contact that may limit the fill factor. These findings help to identify key areas for improvement for these CZTSSe cells in the pursuit of a high performance terawatt-scalable PV technology. In collaboration with Teodor K. Todorov, Aaron Barkhouse, Kejia Wang, David B. Mitzi, Supratik Guha, IBM T J Watson Research Center.

Effect of second-generation antipsychotics on cognition: current issues and future challenges

PubMed Central

Hill, S Kristian; Bishop, Jeffrey R; Palumbo, Donna; Sweeney, John A.

2010-01-01

Generalized cognitive impairments are stable deficits linked to schizophrenia and key factors associated with functional disability in the disorder. Preclinical data suggest that second-generation antipsychotics could potentially reduce cognitive impairments; however, recent large clinical trials indicate only modest cognitive benefits relative to first-generation antipsychotics. This might reflect a limited drug effect in humans, a differential drug effect due to brain alterations associated with schizophrenia, or limited sensitivity of the neuropsychological tests for evaluating cognitive outcomes. New adjunctive procognitive drugs may be needed to achieve robust cognitive and functional improvement. Drug discovery may benefit from greater utilization of translational neurocognitive biomarkers to bridge preclinical and clinical proof-of-concept studies, to optimize assay sensitivity, enhance cost efficiency, and speed progress in drug development. PMID:20021320

[Are non-invasive tests going to replace liver biopsy for diagnosis of liver fibrosis?].

PubMed

Restellini, Sophie; Spahr, Laurent

2012-06-27

Liver fibrosis is associated with chronic liver diseases, and may evolve into cirrhosis that may be complicated by liver failure and portal hypertension. Detection and quantification of liver fibrosis is a key point in the follow-up of patients with chronic liver diseases. Liver biopsy is the gold standard method to assess and quantify fibrosis, but its invasiveness is a limiting factor in everyday clinical practice. Non invasive markers using either biological or radiological parameters have been developed and may decrease the need for liver biopsy in some cases. However, information is limited to fibrosis, and cut-offs values and diagnostic accuracies for significant fibrosis may vary according to the etiology of liver disease. Liver biopsy allows the assessment of intermediate stages of fibrosis and describes accompanying lesions.

The back squat: A proposed assessment of functional deficits and technical factors that limit performance

PubMed Central

Myer, Gregory D.; Kushner, Adam M.; Brent, Jensen L.; Schoenfeld, Brad J.; Hugentobler, Jason; Lloyd, Rhodri S.; Vermeil, Al; Chu, Donald A.; Harbin, Jason; McGill, Stuart M.

2014-01-01

Fundamental movement competency is essential for participation in physical activity and for mitigating the risk of injury, which are both key elements of health throughout life. The squat movement pattern is arguably one of the most primal and critical fundamental movements necessary to improve sport performance, to reduce injury risk and to support lifelong physical activity. Based on current evidence, this first (1 of 2) report deconstructs the technical performance of the back squat as a foundation training exercise and presents a novel dynamic screening tool that incorporates identification techniques for functional deficits that limit squat performance and injury resilience. The follow-up report will outline targeted corrective methodology for each of the functional deficits presented in the assessment tool. PMID:25506270

Characterization of available light for seagrass and patch reef productivity in Sugarloaf Key, Lower Florida Keys

USGS Publications Warehouse

Toro-Farmer, Gerardo; Muller-Karger, Frank E.; Vega-Rodriguez, Maria; Melo, Nelson; Yates, Kimberly K.; Johns, Elizabeth; Cerdeira-Estrada, Sergio; Herwitz, Stan R.

2016-01-01

Light availability is an important factor driving primary productivity in benthic ecosystems, but in situ and remote sensing measurements of light quality are limited for coral reefs and seagrass beds. We evaluated the productivity responses of a patch reef and a seagrass site in the Lower Florida Keys to ambient light availability and spectral quality. In situ optical properties were characterized utilizing moored and water column bio-optical and hydrographic measurements. Net ecosystem productivity (NEP) was also estimated for these study sites using benthic productivity chambers. Our results show higher spectral light attenuation and absorption, and lower irradiance during low tide in the patch reef, tracking the influx of materials from shallower coastal areas. In contrast, the intrusion of clearer surface Atlantic Ocean water caused lower values of spectral attenuation and absorption, and higher irradiance in the patch reef during high tide. Storms during the studied period, with winds >10 m·s−1, caused higher spectral attenuation values. A spatial gradient of NEP was observed, from high productivity in the shallow seagrass area, to lower productivity in deeper patch reefs. The highest daytime NEP was observed in the seagrass, with values of almost 0.4 g·O2·m−2·h−1. Productivity at the patch reef area was lower in May than during October 2012 (mean = 0.137 and 0.177 g·O2·m−2·h−1, respectively). Higher photosynthetic active radiation (PAR) levels measured above water and lower light attenuation in the red region of the visible spectrum (~666 to ~699 nm) had a positive correlation with NEP. Our results indicate that changes in light availability and quality by suspended or resuspended particles limit benthic productivity in the Florida Keys.

A direct link between carbohydrate utilization and virulence in the major human pathogen group A Streptococcus.

PubMed

Shelburne, Samuel A; Keith, David; Horstmann, Nicola; Sumby, Paul; Davenport, Michael T; Graviss, Edward A; Brennan, Richard G; Musser, James M

2008-02-05

Although central to pathogenesis, the molecular mechanisms used by microbes to regulate virulence factor production in specific environments during host-pathogen interaction are poorly defined. Several recent ex vivo and in vivo studies have found that the level of group A Streptococcus (GAS) virulence factor gene transcripts is temporally related to altered expression of genes encoding carbohydrate utilization proteins. These findings stimulated us to analyze the role in pathogenesis of catabolite control protein A (CcpA), a GAS ortholog of a key global regulator of carbohydrate metabolism in Bacillus subtilis. Inasmuch as the genomewide effects of CcpA in a human pathogen are unknown, we analyzed the transcriptome of a DeltaccpA isogenic mutant strain grown in nutrient-rich medium. CcpA influences the transcript levels of many carbohydrate utilization genes and several well characterized GAS virulence factors, including the potent cytolysin streptolysin S. Compared with the wild-type parental strain, the DeltaccpA isogenic mutant strain was significantly less virulent in a mouse model of invasive infection. Moreover, the isogenic mutant strain was significantly impaired in ability to colonize the mouse oropharynx. When grown in human saliva, a nutrient-limited environment, CcpA influenced production of several key virulence factors not influenced during growth in nutrient-rich medium. Purified recombinant CcpA bound to the promoter region of the gene encoding streptolysin S. Our discovery that GAS virulence and complex carbohydrate utilization are directly linked through CcpA provides enhanced understanding of a mechanism used by a Gram-positive pathogen to modulate virulence factor production in specific environments.

Enhanced Two-Factor Authentication and Key Agreement Using Dynamic Identities in Wireless Sensor Networks.

PubMed

Chang, I-Pin; Lee, Tian-Fu; Lin, Tsung-Hung; Liu, Chuan-Ming

2015-11-30

Key agreements that use only password authentication are convenient in communication networks, but these key agreement schemes often fail to resist possible attacks, and therefore provide poor security compared with some other authentication schemes. To increase security, many authentication and key agreement schemes use smartcard authentication in addition to passwords. Thus, two-factor authentication and key agreement schemes using smartcards and passwords are widely adopted in many applications. Vaidya et al. recently presented a two-factor authentication and key agreement scheme for wireless sensor networks (WSNs). Kim et al. observed that the Vaidya et al. scheme fails to resist gateway node bypassing and user impersonation attacks, and then proposed an improved scheme for WSNs. This study analyzes the weaknesses of the two-factor authentication and key agreement scheme of Kim et al., which include vulnerability to impersonation attacks, lost smartcard attacks and man-in-the-middle attacks, violation of session key security, and failure to protect user privacy. An efficient and secure authentication and key agreement scheme for WSNs based on the scheme of Kim et al. is then proposed. The proposed scheme not only solves the weaknesses of previous approaches, but also increases security requirements while maintaining low computational cost.

The health and wellbeing needs of veterans: a rapid review.

PubMed

Oster, Candice; Morello, Andrea; Venning, Anthony; Redpath, Paula; Lawn, Sharon

2017-12-29

For the majority of serving members, life in the military has a positive effect on wellbeing. However, the type, intensity and duration of service, along with the transition from fulltime military to civilian life, may have a negative effect on veterans' wellbeing. Such negative consequences, alongside the growing veteran population, indicate the need for greater exploration of veterans' physical, mental and social wellbeing. The current paper reports on the findings of a rapid review of the literature on the health and wellbeing needs of veterans, commissioned by the Australian Department of Veterans' Affairs to inform future programs and services. The databases Embase, Medline, Cinahl, PubMed, Web of Science and Cochrane Database were searched for systematic reviews reporting on veterans' physical, mental and social wellbeing published in English in peer-reviewed journals. A total of 21 systematic reviews were included. The reviews reported on a range of mental, physical and social health problems affecting veterans. While there was limited information on prevalence rates of physical, mental and social health problems in veterans compared to civilian populations, the reviews demonstrated the interconnection between these domains and the effect of demographic and military service factors. A key finding of the review is the interconnection of the mental, physical, and social health of veterans, highlighting the importance that an integrated approach to veterans' wellbeing is adopted. It is suggested that understanding key factors, such as demographic factors and factors relating to military service, can support improved service provision for veterans.

Social determinants of health in epilepsy.

PubMed

Szaflarski, Magdalena

2014-12-01

Social factors have been identified as key drivers of epilepsy care, outcomes, and disparities, but there is a limited understanding of what these factors are and how they translate into disparities. This targeted review provides an overview of the social determinants of health framework and applies this perspective to the literature about social and psychosocial factors in epilepsy; a social determinants of health--epilepsy model is proposed. The key social determinants of health in epilepsy include socioeconomic status, race/ethnicity, age, and gender. For example, low socioeconomic status and minority status have been associated with a higher risk of epilepsy, more hospitalizations and emergency room visits (versus neurology services), antiepileptic drug nonadherence, and a lower rate of epilepsy surgery. Such differences in care/treatment and outcomes translate into health disparities, many of which are considered unjust (inequitable) and modifiable through social action. Other social determinants of health include structural and sociocultural contextual conditions (e.g., health economy, policy, and social stigma/discrimination) and mediating mechanisms including material (e.g., housing), behavioral/biological (e.g., adherence), psychosocial (e.g., perceived stigma), and health system (e.g., access) factors. There are complex relationships among social determinants of health in epilepsy, which remain poorly understood and hamper efforts to address and eliminate disparities in epilepsy care and outcomes. Further empirical work grounded in sound theory and robust methodologies is needed to identify points of intervention and design effective and socially acceptable solutions to any pervasive disparities in epilepsy. Copyright © 2014 Elsevier Inc. All rights reserved.

Harmful cyanobacterial blooms: causes, consequences, and controls.

PubMed

Paerl, Hans W; Otten, Timothy G

2013-05-01

Cyanobacteria are the Earth's oldest oxygenic photoautotrophs and have had major impacts on shaping its biosphere. Their long evolutionary history (≈ 3.5 by) has enabled them to adapt to geochemical and climatic changes, and more recently anthropogenic modifications of aquatic environments, including nutrient over-enrichment (eutrophication), water diversions, withdrawals, and salinization. Many cyanobacterial genera exhibit optimal growth rates and bloom potentials at relatively high water temperatures; hence global warming plays a key role in their expansion and persistence. Bloom-forming cyanobacterial taxa can be harmful from environmental, organismal, and human health perspectives by outcompeting beneficial phytoplankton, depleting oxygen upon bloom senescence, and producing a variety of toxic secondary metabolites (e.g., cyanotoxins). How environmental factors impact cyanotoxin production is the subject of ongoing research, but nutrient (N, P and trace metals) supply rates, light, temperature, oxidative stressors, interactions with other biota (bacteria, viruses and animal grazers), and most likely, the combined effects of these factors are all involved. Accordingly, strategies aimed at controlling and mitigating harmful blooms have focused on manipulating these dynamic factors. The applicability and feasibility of various controls and management approaches is discussed for natural waters and drinking water supplies. Strategies based on physical, chemical, and biological manipulations of specific factors show promise; however, a key underlying approach that should be considered in almost all instances is nutrient (both N and P) input reductions; which have been shown to effectively reduce cyanobacterial biomass, and therefore limit health risks and frequencies of hypoxic events.

Identification of key factors affecting the water pollutant concentration in the sluice-controlled river reaches of the Shaying River in China via statistical analysis methods.

PubMed

Dou, Ming; Zhang, Yan; Zuo, Qiting; Mi, Qingbin

2015-08-01

The construction of sluices creates a strong disturbance in water environmental factors within a river. The change in water pollutant concentrations of sluice-controlled river reaches (SCRRs) is more complex than that of natural river segments. To determine the key factors affecting water pollutant concentration changes in SCRRs, river reaches near the Huaidian Sluice in the Shaying River of China were selected as a case study, and water quality monitoring experiments based on different regulating modes were implemented in 2009 and 2010. To identify the key factors affecting the change rates for the chemical oxygen demand of permanganate (CODMn) and ammonia nitrogen (NH3-N) concentrations in the SCRRs of the Huaidian Sluice, partial correlation analysis, principal component analysis and principal factor analysis were used. The results indicate four factors, i.e., the inflow quantity from upper reaches, opening size of sluice gates, water pollutant concentration from upper reaches, and turbidity before the sluice, which are the common key factors for the CODMn and NH3-N concentration change rates. Moreover, the dissolved oxygen before a sluice is a key factor for the permanganate concentration from CODMn change rate, and the water depth before a sluice is a key factor for the NH3-N concentration change rate. Multiple linear regressions between the water pollutant concentration change rate and key factors were established via multiple linear regression analyses, and the quantitative relationship between the CODMn and NH3-N concentration change rates and key affecting factors was analyzed. Finally, the mechanism of action for the key factors affecting the water pollutant concentration changes was analyzed. The results reveal that the inflow quantity from upper reaches, opening size of sluice gates, permanganate concentration from CODMn from upper reaches and dissolved oxygen before the sluice have a negative influence and the turbidity before the sluice has a positive influence on the permanganate concentration from CODMn change rates and that the opening size of sluice gates, NH3-N concentration from upper reaches, and water depth before the sluice have a negative influence and the inflow quantity from upper reaches and turbidity before the sluice have a positive influence on the NH3-N concentration change rates, which provides a scientific grounding for pollution control and sluice operations in SCRRs.

Understanding Suicide Across the Lifespan: A United States Perspective of Suicide Risk Factors, Assessment & Management.

PubMed

Steele, Ian H; Thrower, Natasha; Noroian, Paul; Saleh, Fabian M

2018-01-01

Suicide is a troubling, preventable phenomenon. Prior to attempts, individuals often seek help, prompting practitioners to perform risk assessments that ideally use evidence-based risk management strategies. A literature review was performed using Harvard Countway Library of Medicine, Google Scholar, PubMed. Key words used were "Forensic Science," "Suicide Risk Management," "Pediatric Suicide Risk Factors," "Adult Suicide Risk Factors," "Geriatric Suicide Risk Factors," "Suicide Risk Assessment." Parameters limited articles to studies/reviews completed in the past twenty years in the United States. Results indicated predictors of suicide in juveniles were insomnia, burdensomeness, and recent conflicts with family or a romantic partner. Adults had greater risk if male, substance abusing, with marital/job loss. Elderly individuals with multiple medical comorbidities, hopelessness, and isolation were at higher risk. Everyone evaluated should be screened for access to firearms. Management of suicide risk involves providing the least restrictive form of treatment which maintains an individual's safety. © 2017 American Academy of Forensic Sciences.

Fundamental finite key limits for one-way information reconciliation in quantum key distribution

NASA Astrophysics Data System (ADS)

Tomamichel, Marco; Martinez-Mateo, Jesus; Pacher, Christoph; Elkouss, David

2017-11-01

The security of quantum key distribution protocols is guaranteed by the laws of quantum mechanics. However, a precise analysis of the security properties requires tools from both classical cryptography and information theory. Here, we employ recent results in non-asymptotic classical information theory to show that one-way information reconciliation imposes fundamental limitations on the amount of secret key that can be extracted in the finite key regime. In particular, we find that an often used approximation for the information leakage during information reconciliation is not generally valid. We propose an improved approximation that takes into account finite key effects and numerically test it against codes for two probability distributions, that we call binary-binary and binary-Gaussian, that typically appear in quantum key distribution protocols.

A qualitative study explaining nurses' perceptions of quality care for older people in long-term care settings in Ireland.

PubMed

Murphy, Kathy

2007-03-01

The aim of this research was to explore nurses' perceptions of the attributes of quality care and the factors that facilitate or hinder high-quality nursing care in long-term care. The quality of care for older people living in long-term care has been identified as an issue of concern in many nursing research studies. While many factors have been identified, it is difficult to determine key factors from current research. The study was a qualitative exploration of nurses' perceptions of quality care for older people and the factors that facilitate or hinder quality care. It involved 20 interviews with nurses. Respondents were asked to illustrate their accounts with examples from practice. This phase of the research was guided by the principles of hermeneutic phenomenology and the analysis process by Van Manen. The findings indicated that nurses perceived quality care for older people in Ireland as holistic, individualized and focused on promoting independence and choice. The research revealed, however, that care in many practice areas was not individualized, patient choice and involvement in decision making was limited and some areas engendered dependency. While staffing was identified as a factor which had an impact on the provision of patient choice, other issues, such as the motivation of staff, the role of the ward manager and the dominance of routine were also highlighted. There is a need to review organizational approaches to care, develop patient centred approaches to care and provide educational support for managers. This research focuses on care for older people; it helps practitioners identify key factors in the provision of quality care for older people living in long-term care.

Assessing risk factors for dental caries: a statistical modeling approach.

PubMed

Trottini, Mario; Bossù, Maurizio; Corridore, Denise; Ierardo, Gaetano; Luzzi, Valeria; Saccucci, Matteo; Polimeni, Antonella

2015-01-01

The problem of identifying potential determinants and predictors of dental caries is of key importance in caries research and it has received considerable attention in the scientific literature. From the methodological side, a broad range of statistical models is currently available to analyze dental caries indices (DMFT, dmfs, etc.). These models have been applied in several studies to investigate the impact of different risk factors on the cumulative severity of dental caries experience. However, in most of the cases (i) these studies focus on a very specific subset of risk factors; and (ii) in the statistical modeling only few candidate models are considered and model selection is at best only marginally addressed. As a result, our understanding of the robustness of the statistical inferences with respect to the choice of the model is very limited; the richness of the set of statistical models available for analysis in only marginally exploited; and inferences could be biased due the omission of potentially important confounding variables in the model's specification. In this paper we argue that these limitations can be overcome considering a general class of candidate models and carefully exploring the model space using standard model selection criteria and measures of global fit and predictive performance of the candidate models. Strengths and limitations of the proposed approach are illustrated with a real data set. In our illustration the model space contains more than 2.6 million models, which require inferences to be adjusted for 'optimism'.

Multi-factor authentication

DOEpatents

Hamlet, Jason R; Pierson, Lyndon G

2014-10-21

Detection and deterrence of spoofing of user authentication may be achieved by including a cryptographic fingerprint unit within a hardware device for authenticating a user of the hardware device. The cryptographic fingerprint unit includes an internal physically unclonable function ("PUF") circuit disposed in or on the hardware device, which generates a PUF value. Combining logic is coupled to receive the PUF value, combines the PUF value with one or more other authentication factors to generate a multi-factor authentication value. A key generator is coupled to generate a private key and a public key based on the multi-factor authentication value while a decryptor is coupled to receive an authentication challenge posed to the hardware device and encrypted with the public key and coupled to output a response to the authentication challenge decrypted with the private key.

Wound Healing Essentials: Let There Be Oxygen

PubMed Central

Sen, Chandan K.

2009-01-01

The state of wound oxygenation is a key determinant of healing outcomes. From a diagnostic standpoint, measurements of wound oxygenation are commonly used to guide treatment planning such as amputation decision. In preventive applications, optimizing wound perfusion and providing supplemental O2 in the peri-operative period reduces the incidence of post-operative infections. Correction of wound pO2 may, by itself, trigger some healing responses. Importantly, approaches to correct wound pO2 favorably influence outcomes of other therapies such as responsiveness to growth factors and acceptance of grafts. Chronic ischemic wounds are essentially hypoxic. Primarily based on the tumor literature, hypoxia is generally viewed as being angiogenic. This is true with the condition that hypoxia be acute and mild to modest in magnitude. Extreme near-anoxic hypoxia, as commonly noted in problem wounds, is not compatible with tissue repair. Adequate wound tissue oxygenation is required but may not be sufficient to favorably influence healing outcomes. Success in wound care may be improved by a personalized health care approach. The key lies in our ability to specifically identify the key limitations of a given wound and in developing a multifaceted strategy to specifically address those limitations. In considering approaches to oxygenate the wound tissue it is important to recognize that both too little as well as too much may impede the healing process. Oxygen dosing based on the specific need of a wound therefore seems prudent. Therapeutic approaches targeting the oxygen sensing and redox signaling pathways are promising. PMID:19152646

Identification of Barriers to Pediatric Care in Limited-Resource Settings: A Simulation Study.

PubMed

Shilkofski, Nicole; Hunt, Elizabeth A

2015-12-01

Eighty percent of the 10 million annual deaths in children aged <5 years in developing countries are estimated to be avoidable, with improvements in education for pediatric emergency management being a key factor. Education must take into account cultural considerations to be effective. Study objectives were: (1) to use simulation to identify factors posing barriers to patient care in limited resource settings (LRS); and (2) to understand how simulations in LRS can affect communication and decision-making processes. A qualitative study was conducted at 17 different sites in 12 developing countries in Asia, Latin America, and Africa. Data from observations of 68 in situ simulated pediatric emergencies were coded for thematic analysis. Sixty-two different "key informants" were interviewed regarding perceived benefit of simulations. Coding of observations and interviews yielded common themes: impact of culture on team hierarchy, impact of communication and language barriers on situational awareness, systematic emergency procedures, role delineation, shared cognition and resource awareness through simulation, logistic barriers to patient care, and use of recognition-primed decision-making by experienced clinicians. Changes in clinical environments were implemented as a result of simulations. Ad hoc teams in LRS face challenges in caring safely for patients; these include language and cultural barriers, as well as environmental and resource constraints. Engaging teams in simulations may promote improved communication, identification of systems issues and latent threats to target for remediation. There may be a role for training novices in use of recognition-primed or algorithmic decision-making strategies to improve rapidity and efficiency of decisions in LRS. Copyright © 2015 by the American Academy of Pediatrics.

A rhamnose-rich O-antigen mediates adhesion, virulence, and host colonization for the xylem-limited phytopathogen Xylella fastidiosa.

PubMed

Clifford, Jennifer C; Rapicavoli, Jeannette N; Roper, M Caroline

2013-06-01

Xylella fastidiosa is a gram-negative, xylem-limited bacterium that causes a lethal disease of grapevine called Pierce's disease. Lipopolysaccharide (LPS) composes approximately 75% of the outer membrane of gram-negative bacteria and, because it is largely displayed on the cell surface, it mediates interactions between the bacterial cell and its surrounding environment. LPS is composed of a conserved lipid A-core oligosaccharide component and a variable O-antigen portion. By targeting a key O-antigen biosynthetic gene, we demonstrate the contribution of the rhamnose-rich O-antigen to surface attachment, cell-cell aggregation, and biofilm maturation: critical steps for successful infection of the host xylem tissue. Moreover, we have demonstrated that a fully formed O-antigen moiety is an important virulence factor for Pierce's disease development in grape and that depletion of the O-antigen compromises its ability to colonize the host. It has long been speculated that cell-surface polysaccharides play a role in X. fastidiosa virulence and this study confirms that LPS is a major virulence factor for this important agricultural pathogen.

The formation of acrylamide in UK cereal products.

PubMed

Sadd, Peter; Hamlet, Colin

2005-01-01

Many bakery products sold in the UK such as crumpets, batch bread and Naan might be expected to show high levels of acrylamide because they have strong Maillard colours and flavours. However, analysis of commercial products has shown that the highest levels of acrylamide are seen in dry biscuit type products. With the exception of spiced products such as ginger cake, moist high sugar products (e.g. cakes and fruit loaves) show relatively low levels of acrylamide, even in darkly browned crusts. This is in contrast to bread where acrylamide levels in excess of 100 microg/kg are common in the crust region, but are diluted by low levels in the crumb. Acrylamide levels in bread are significantly raised by domestic toasting, but other products such as crumpets and Naan bread have been found to be less sensitive. A mathematical model has been developed (and validated against tests on model dough) which shows that once obvious recipe differences are allowed for, the key factor limiting acrylamide levels is crust moisture. Chemical decay of acrylamide and depletion of amino acids are also limiting factors at higher temperatures.

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

Critchlow, Terence J.; Abdulla, Ghaleb; Becla, Jacek

Data management is the organization of information to support efficient access and analysis. For data intensive computing applications, the speed at which relevant data can be accessed is a limiting factor in terms of the size and complexity of computation that can be performed. Data access speed is impacted by the size of the relevant subset of the data, the complexity of the query used to define it, and the layout of the data relative to the query. As the underlying data sets become increasingly complex, the questions asked of it become more involved as well. For example, geospatial datamore » associated with a city is no longer limited to the map data representing its streets, but now also includes layers identifying utility lines, key points, locations and types of businesses within the city limits, tax information for each land parcel, satellite imagery, and possibly even street-level views. As a result, queries have gone from simple questions, such as "how long is Main Street?", to much more complex questions such as "taking all other factors into consideration, are the property values of houses near parks higher than those under power lines, and if so, by what percentage". Answering these questions requires a coherent infrastructure, integrating the relevant data into a format optimized for the questions being asked.« less

A host basal transcription factor is a key component for infection of rice by TALE-carrying bacteria

PubMed Central

Yuan, Meng; Ke, Yinggen; Huang, Renyan; Ma, Ling; Yang, Zeyu; Chu, Zhaohui; Xiao, Jinghua; Li, Xianghua; Wang, Shiping

2016-01-01

Transcription activator-like effectors (TALEs) are sequence-specific DNA binding proteins found in a range of plant pathogenic bacteria, where they play important roles in host-pathogen interactions. However, it has been unclear how TALEs, after they have been injected into the host cells, activate transcription of host genes required for infection success. Here, we show that the basal transcription factor IIA gamma subunit TFIIAγ5 from rice is a key component for infection by the TALE-carrying bacterium Xanthomonas oryzae pv. oryzae, the causal agent for bacterial blight. Direct interaction of several TALEs with TFIIAγ5 is required for activation of disease susceptibility genes. Conversely, reduced expression of the TFIIAγ5 host gene limits the induction of susceptibility genes and thus decreases bacterial blight symptoms. Suppression or mutation of TFIIAγ5 can also reduce bacterial streak, another devastating disease of rice caused by TALE-carrying X. oryzae pv. oryzicola. These results have important implications for formulating a widely applicable strategy with which to improve resistance of plants to TALE-carrying pathogens. DOI: http://dx.doi.org/10.7554/eLife.19605.001 PMID:27472897

Induced stem cell neoplasia in a cnidarian by ectopic expression of a POU domain transcription factor.

PubMed

Millane, R Cathriona; Kanska, Justyna; Duffy, David J; Seoighe, Cathal; Cunningham, Stephen; Plickert, Günter; Frank, Uri

2011-06-01

The evolutionary origin of stem cell pluripotency is an unresolved question. In mammals, pluripotency is limited to early embryos and is induced and maintained by a small number of key transcription factors, of which the POU domain protein Oct4 is considered central. Clonal invertebrates, by contrast, possess pluripotent stem cells throughout their life, but the molecular mechanisms that control their pluripotency are poorly defined. To address this problem, we analyzed the expression pattern and function of Polynem (Pln), a POU domain gene from the marine cnidarian Hydractinia echinata. We show that Pln is expressed in the embryo and adult stem cells of the animal and that ectopic expression in epithelial cells induces stem cell neoplasms and loss of epithelial tissue. Neoplasm cells downregulated the transgene but expressed the endogenous Pln gene and also Nanos, Vasa, Piwi and Myc, which are all known cnidarian stem cell markers. Retinoic acid treatment caused downregulation of Pln and the differentiation of neoplasm cells to neurosensory and epithelial cells. Pln downregulation by RNAi led to differentiation. Collectively, our results suggest an ancient role of POU proteins as key regulators of animal stem cells.

A theoretical model of speed-dependent steering torque for rolling tyres

NASA Astrophysics Data System (ADS)

Wei, Yintao; Oertel, Christian; Liu, Yahui; Li, Xuebing

2016-04-01

It is well known that the tyre steering torque is highly dependent on the tyre rolling speed. In limited cases, i.e. parking manoeuvre, the steering torque approaches the maximum. With the increasing tyre speed, the steering torque decreased rapidly. Accurate modelling of the speed-dependent behaviour for the tyre steering torque is a key factor to calibrate the electric power steering (EPS) system and tune the handling performance of vehicles. However, no satisfactory theoretical model can be found in the existing literature to explain this phenomenon. This paper proposes a new theoretical framework to model this important tyre behaviour, which includes three key factors: (1) tyre three-dimensional transient rolling kinematics with turn-slip; (2) dynamical force and moment generation; and (3) the mixed Lagrange-Euler method for contact deformation solving. A nonlinear finite-element code has been developed to implement the proposed approach. It can be found that the main mechanism for the speed-dependent steering torque is due to turn-slip-related kinematics. This paper provides a theory to explain the complex mechanism of the tyre steering torque generation, which helps to understand the speed-dependent tyre steering torque, tyre road feeling and EPS calibration.

Predicting the enhancement of mixing-driven reactions in nonuniform flows using measures of flow topology.

PubMed

Engdahl, Nicholas B; Benson, David A; Bolster, Diogo

2014-11-01

The ability for reactive constituents to mix is often the key limiting factor for the completion of reactions across a huge range of scales in a variety of media. In flowing systems, deformation and shear enhance mixing by bringing constituents into closer proximity, thus increasing reaction potential. Accurately quantifying this enhanced mixing is key to predicting reactions and typically is done by observing or simulating scalar transport. To eliminate this computationally expensive step, we use a Lagrangian stochastic framework to derive the enhancement to reaction potential by calculating the collocation probability of particle pairs in a heterogeneous flow field accounting for deformations. We relate the enhanced reaction potential to three well known flow topology metrics and demonstrate that it is best correlated to (and asymptotically linear with) one: the largest eigenvalue of the (right) Cauchy-Green tensor.

The influence of sociocultural factors on organ donation and transplantation in Korea: findings from key informant interviews.

PubMed

Kim, Jung Ran; Elliott, Doug; Hyde, Cheryl

2004-04-01

Although brain death was formally recognized in Korea in 2000 for the purpose of organ donation, traditional Confucian-based thought still prevails. The aim of this study was to explore sociocultural perspectives that influence health professionals' attitudes and perceptions regarding organ donation. Semistructured interviews were conducted with nine key informants from three major hospitals providing transplant services in South Korea. Several themes were identified as barriers to organ donation: Confucianism, misunderstandings and myths, organs as spare for selling, lack of clarity in the definition of death in the new legislation, and limited medical insurance coverage. It remains difficult for brain death to be accepted as true death, and there is currently a poor rate of organ procurement. Findings of the study will help identify socioculturally appropriate strategies to promote acceptance and accessibility of organ transplantation among South Koreans.

The Proposal of Key Performance Indicators in Facility Management and Determination the Weights of Significance

NASA Astrophysics Data System (ADS)

Rimbalová, Jarmila; Vilčeková, Silvia

2013-11-01

The practice of facilities management is rapidly evolving with the increasing interest in the discourse of sustainable development. The industry and its market are forecasted to develop to include non-core functions, activities traditionally not associated with this profession, but which are increasingly being addressed by facilities managers. The scale of growth in the built environment and the consequential growth of the facility management sector is anticipated to be enormous. Key Performance Indicators (KPI) are measure that provides essential information about performance of facility services delivery. In selecting KPI, it is critical to limit them to those factors that are essential to the organization reaching its goals. It is also important to keep the number of KPI small just to keep everyone's attention focused on achieving the same KPIs. This paper deals with the determination of weights of KPI of FM in terms of the design and use of sustainable buildings.

Flow-enhanced solution printing of all-polymer solar cells

DOE PAGES

Diao, Ying; Zhou, Yan; Kurosawa, Tadanori; ...

2015-08-12

Morphology control of solution coated solar cell materials presents a key challenge limiting their device performance and commercial viability. Here we present a new concept for controlling phase separation during solution printing using an all-polymer bulk heterojunction solar cell as a model system. The key aspect of our method lies in the design of fluid flow using a microstructured printing blade, on the basis of the hypothesis of flow-induced polymer crystallization. Our flow design resulted in a similar to 90% increase in the donor thin film crystallinity and reduced microphase separated donor and acceptor domain sizes. The improved morphology enhancedmore » all metrics of solar cell device performance across various printing conditions, specifically leading to higher short-circuit current, fill factor, open circuit voltage and significantly reduced device-to-device variation. However, we expect our design concept to have broad applications beyond all-polymer solar cells because of its simplicity and versatility.« less

Conservation challenges and research needs for Pacific lamprey in the Columbia River Basin

USGS Publications Warehouse

Clemens, Benjamin J.; Beamish, Richard J.; Coates, Kelly C.; Docker, Margaret F.; Dunham, Jason B.; Gray, Ann E.; Hess, Jon E.; Jolley, Jeffrey C.; Lampman, Ralph T.; McIlraith, Brian J.; Moser, Mary L.; Murauskas, Joshua G.; Noakes, David L. G.; Schaller, Howard A.; Schreck, Carl B.; Starcevich, Steven J.; Streif, Bianca; van de Wetering, Stan J.; Wade, Joy; Weitkamp, Laurie A.; Wyss, Lance A.

2017-01-01

The Pacific Lamprey Entosphenus tridentatus, an anadromous fish native to the northern Pacific Ocean and bordering freshwater habitats, has recently experienced steep declines in abundance and range contractions along the West Coast of North America. During the early 1990s, Native American tribes recognized the declining numbers of lamprey and championed their importance. In 2012, 26 entities signed a conservation agreement to coordinate and implement restoration and research for Pacific Lamprey. Regional plans have identified numerous threats, monitoring needs, and strategies to conserve and restore Pacific Lamprey during their freshwater life stages. Prime among these are needs to improve lamprey passage, restore freshwater habitats, educate stakeholders, and implement lamprey-specific research and management protocols. Key unknowns include range-wide trends in status, population dynamics, population delineation, limiting factors, and marine influences. We synthesize these key unknowns, with a focus on the freshwater life stages of lamprey in the Columbia River basin.

Extending Raman's reach: enabling applications via greater sensitivity and speed

NASA Astrophysics Data System (ADS)

Creasey, David; Sullivan, Mike; Paul, Chris; Rathmell, Cicely

2018-02-01

Over the last decade, miniature fiber optic spectrometers have greatly expanded the ability of Raman spectroscopy to tackle practical applications in the field, from mobile pharmaceutical ID to hazardous material assessment in remote locations. There remains a gap, however, between the typical diode array spectrometer and their more sensitive benchtop analogs. High sensitivity, cooled Raman spectrometers have the potential to narrow that gap by providing greater sensitivity, better SNR, and faster measurement times. In this paper, we'll look at the key factors in the design of high sensitivity miniature Raman spectrometers and their associated accessories, as well as the key metric for direct comparison of these systems - limit of detection. With the availability of our high sensitivity Raman systems operating at wavelengths from the UV to NIR, many applications are now becoming practical in the field, from trace level detection to analysis of complex biological samples.

Electronic Nicotine Delivery Systems (ENDS): What Nurses Need to Know.

PubMed

Essenmacher, Carol; Naegle, Madeline; Baird, Carolyn; Vest, Bridgette; Spielmann, Rene; Smith-East, Marie; Powers, Leigh

Efforts to decrease adverse effects of tobacco use are affected by emergence of new nicotine delivery products. Advertising, product promotion, and social media promote use of these products, yet a lack of evidence regarding safety leaves nurses unprepared to counsel patients. To critically evaluate current research, reviews of literature, expert opinion, and stakeholder policy proposals on use and safety of electronic nicotine delivery systems (ENDS). A targeted examination of literature generated by key stakeholders and subject matter experts was conducted using key words, modified by risk factors, and limited to the past 8 years. Current knowledge gaps in research literature and practice implications of the literature are discussed. The safety of ENDS is questionable and unclear. There are clear health risks of nicotine exposure to developing brains. Potential health risks of ENDS secondhand emissions exposure exist. Using ENDS to facilitate total tobacco cessation is not proven.

Analysis of fatigue reliability for high temperature and high pressure multi-stage decompression control valve

NASA Astrophysics Data System (ADS)

Yu, Long; Xu, Juanjuan; Zhang, Lifang; Xu, Xiaogang

2018-03-01

Based on stress-strength interference theory to establish the reliability mathematical model for high temperature and high pressure multi-stage decompression control valve (HMDCV), and introduced to the temperature correction coefficient for revising material fatigue limit at high temperature. Reliability of key dangerous components and fatigue sensitivity curve of each component are calculated and analyzed by the means, which are analyzed the fatigue life of control valve and combined with reliability theory of control valve model. The impact proportion of each component on the control valve system fatigue failure was obtained. The results is shown that temperature correction factor makes the theoretical calculations of reliability more accurate, prediction life expectancy of main pressure parts accords with the technical requirements, and valve body and the sleeve have obvious influence on control system reliability, the stress concentration in key part of control valve can be reduced in the design process by improving structure.

Flow-enhanced solution printing of all-polymer solar cells

PubMed Central

Diao, Ying; Zhou, Yan; Kurosawa, Tadanori; Shaw, Leo; Wang, Cheng; Park, Steve; Guo, Yikun; Reinspach, Julia A.; Gu, Kevin; Gu, Xiaodan; Tee, Benjamin C. K.; Pang, Changhyun; Yan, Hongping; Zhao, Dahui; Toney, Michael F.; Mannsfeld, Stefan C. B.; Bao, Zhenan

2015-01-01

Morphology control of solution coated solar cell materials presents a key challenge limiting their device performance and commercial viability. Here we present a new concept for controlling phase separation during solution printing using an all-polymer bulk heterojunction solar cell as a model system. The key aspect of our method lies in the design of fluid flow using a microstructured printing blade, on the basis of the hypothesis of flow-induced polymer crystallization. Our flow design resulted in a ∼90% increase in the donor thin film crystallinity and reduced microphase separated donor and acceptor domain sizes. The improved morphology enhanced all metrics of solar cell device performance across various printing conditions, specifically leading to higher short-circuit current, fill factor, open circuit voltage and significantly reduced device-to-device variation. We expect our design concept to have broad applications beyond all-polymer solar cells because of its simplicity and versatility. PMID:26264528

The Cyber Security Crisis

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

Spafford, Eugene

2006-05-10

Despite considerable activity and attention, the overall state of information security continues to get worse. Attacks are increasing, fraud and theft are rising, and losses may exceed $100 billion per year worldwide. Many factors contribute to this, including misplaced incentives for industry, a lack of attention by government, ineffective law enforcement, and an uninformed image of who the perpetrators really are. As a result, many of the intended attempts at solutions are of limited (if any) overall effectiveness. This presentation will illustrate some key aspects of the cyber security problem and its magnitude, as well as provide some insight intomore » causes and enabling factors. The talk will conclude with some observations on how the computing community can help improve the situation, as well as some suggestions for 'cyber self-defense.'« less

Support of the supporters.

PubMed

Stiefel, F

2008-02-01

A growing body of evidence indicates that health care professionals working with severely ill patients are in need of support. Beside "external" factors, such as heavy clinical patient volume or administrative duties, "intra-psychic stressors," related to the inner significance of contextual factors, are an important source of clinician's distress. Identification of and working through intrapsychic stressors can considerably reduce psychological distress and thus provide effective and long-lasting support of the oncology clinician. This article discusses key elements of intra-psychic stressors, namely (1) emotions towards the patient, (2) awareness of own limits, (3) confusion about empathy, identification, counter-transference and collusion, (4) the influence of early development and life trajectory on career choices and professional identity and (5) the conflicting roles a health care professional being in need of support has to face.

The genetics and genomics of thoracic aortic disease

PubMed Central

Pomianowski, Pawel

2013-01-01

Genetic studies over the past several decades have helped to better elucidate the genomics and inheritance of thoracic aortic diseases. Seminal work from various researchers have identified several genetic factors and mutations that predispose to aortic aneurysms, which will aid in better screening and early intervention, resulting in better clinical outcomes. Syndromic aneurysms have been associated with Marfan syndrome, Loeys-Dietz syndrome, aneurysm osteoarthritis syndrome, arterial tortuosity syndrome, Ehlers-Danlos Syndrome, and TGFβ mutation. Mutations in MYH11, TGFβR1, TGFβR2, MYLK, and ACTA2 genes have been linked to familial non-syndromic cases, although linkage analysis is limited by incomplete penetrance and/or locus heterogeneity. This overview presents a summary of key genetic and genomic factors that are associated with thoracic aortic diseases. PMID:23977594

Weighing the impact (factor) of publishing in veterinary journals.

PubMed

Christopher, Mary M

2015-06-01

The journal in which you publish your research can have a major influence on the perceived value of your work and on your ability to reach certain audiences. The impact factor, a widely used metric of journal quality and prestige, has evolved into a benchmark of quality for institutions and graduate programs and, inappropriately, as a proxy for the quality of individual authors and articles, affecting tenure, promotion, and funding decisions. As a result, despite its many limitations, publishing decisions by authors often are based solely on a journal's impact factor. This can disadvantage journals in small disciplines, such as veterinary medicine, and limit the ability of authors to reach key audiences. In this article, factors that can influence the impact factor of a journal and its applicability, including precision, citation practices, article type, editorial policies, and size of the research community will be reviewed. The value and importance of veterinary journals such as the Journal of Veterinary Cardiology for reaching relevant audiences and for helping shape disciplinary specialties and influence clinical practice will also be discussed. Lastly, the efforts underway to develop alternative measures to assess the scientific quality of individual authors and articles, such as article-level metrics, as well as institutional measures of the economic and social impact of biomedical research will be considered. Judicious use of the impact factor and the implementation of new metrics for assessing the quality and societal relevance of veterinary research articles will benefit both authors and journals. Copyright © 2015 Elsevier B.V. All rights reserved.

Factors that influence career progression among postdoctoral clinical academics: a scoping review of the literature.

PubMed

Ranieri, Veronica; Barratt, Helen; Fulop, Naomi; Rees, Geraint

2016-10-21

The future of academic medicine is uncertain. Concerns regarding the future availability of qualified and willing trainee clinical academics have been raised worldwide. Of significant concern is our failure to retain postdoctoral trainee clinical academics, who are likely to be our next generation of leaders in scientific discovery. To review the literature about factors that may influence postdoctoral career progression in early career clinical academics. This study employed a scoping review method. Three reviewers separately assessed whether the articles found fit the inclusion criteria. PubMed, Scopus, Web of Science and Google Scholar (1991-2015). The review encompassed a broad search of English language studies published anytime up to November 2015. All articles were eligible for inclusion, including research papers employing either quantitative or qualitative methods, as well as editorials and other summary articles. Data extracted from included publications were charted according to author(s), sample population, study design, key findings, country of origin and year of publication. Our review identified 6 key influences: intrinsic motivation, work-life balance, inclusiveness, work environment, mentorship and availability of funding. It also detected significant gaps within the literature about these influences. Three key steps are proposed to help support postdoctoral trainee clinical academics. These focus on ensuring that researchers feel encouraged in their workplace, involved in collaborative dialogue with key stakeholders and able to access reliable information regarding their chosen career pathway. Finally, we highlight recommendations for future research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Collaboration between employers and occupational health service providers: a systematic review of key characteristics.

PubMed

Halonen, Jaana I; Atkins, Salla; Hakulinen, Hanna; Pesonen, Sanna; Uitti, Jukka

2017-01-05

Employees are major contributors to economic development, and occupational health services (OHS) can have an important role in supporting their health. Key to this is collaboration between employers and OHS. We reviewed the evidence regarding the characteristics of good collaboration between employers and OHS providers that is essential to construct more effective collaboration and services. A systematic review of the factors of good collaboration between employers and OHS providers was conducted. We searched five databases between January 2000 and March 2016 and back referenced included articles. Two reviewers evaluated 639 titles, 63 abstracts and 20 full articles, and agreed that six articles, all on qualitative studies, met the predetermined relevance and publication criteria and were included. Data were extracted by one reviewer and checked by a second reviewer and analysed using thematic analysis. Three themes and nine subthemes related to good collaboration were identified. The first theme included time, space and contract requirements for effective collaboration with three subthemes (i.e., key characteristics): flexible OHS/flexible contracts including tailor-made services accounting for the needs of the employer, geographical proximity of the stakeholders allowing easy access to services, and long-term contracts as collaboration develops over time. The second theme was related to characteristics of the dialogue in effective collaboration that consisted of shared goals, reciprocity, frequent contact and trust. According to the third theme the definition of roles of the stakeholders was important; OHS providers should have competence and knowledge about the workplace, become strategic partners with the employers as well as provide quality services. Although literature regarding collaboration between the employers and OHS providers was limited, we identified several key factors that contribute to effective collaboration. This information is useful in developing indicators of effective collaboration that will enable organisation of more effective OHS practices.

Understanding the underlying drivers of inpatient cost growth: a literature review.

PubMed

Goetghebeur, Mireille M; Forrest, Sharon; Hay, Joel W

2003-06-01

After the declining growth in inpatient hospital spending that occurred from 1994 through 1998, the recent trend in increased spending has been of concern to many. Understanding the underlying reasons for this new growth will aid decision makers in finding best means to manage inpatient costs. To identify potential contributors to recent growth in inpatient spending. Literature review. Healthcare and economic databases, prominent Web sites, and key journals were searched to identify potential drivers for the 1999-2001 rise in inpatient spending. Initial literature review and state-level regression analyses published in a companion paper were used to identify key explanatory factors, which were further explored. Although many of the contributors to the rise in inpatient costs overlap and are interrelated, the major cost drivers were identified as (1) workforce shortage; (2) new technology; (3) less tightly managed care; and (4) shifting hospital business directions. Underlying factors such as legislation, quality of care, limited access to noninpatient care, pressures on the safety net, population aging, and increasing chronic illness prevalence were found to influence the contributors and healthcare spending in general. Future trends in inpatient spending will depend on the response of the healthcare system to these cost drivers and underlying factors. Potential avenues to control inpatient spending include expanding access to primary care, encouraging cost-effective technology and more efficient hospital market structures, and developing incentives for the healthcare workforce.

Accessing key steps of human tumor progression in vivo by using an avian embryo model

NASA Astrophysics Data System (ADS)

Hagedorn, Martin; Javerzat, Sophie; Gilges, Delphine; Meyre, Aurélie; de Lafarge, Benjamin; Eichmann, Anne; Bikfalvi, Andreas

2005-02-01

Experimental in vivo tumor models are essential for comprehending the dynamic process of human cancer progression, identifying therapeutic targets, and evaluating antitumor drugs. However, current rodent models are limited by high costs, long experimental duration, variability, restricted accessibility to the tumor, and major ethical concerns. To avoid these shortcomings, we investigated whether tumor growth on the chick chorio-allantoic membrane after human glioblastoma cell grafting would replicate characteristics of the human disease. Avascular tumors consistently formed within 2 days, then progressed through vascular endothelial growth factor receptor 2-dependent angiogenesis, associated with hemorrhage, necrosis, and peritumoral edema. Blocking of vascular endothelial growth factor receptor 2 and platelet-derived growth factor receptor signaling pathways by using small-molecule receptor tyrosine kinase inhibitors abrogated tumor development. Gene regulation during the angiogenic switch was analyzed by oligonucleotide microarrays. Defined sample selection for gene profiling permitted identification of regulated genes whose functions are associated mainly with tumor vascularization and growth. Furthermore, expression of known tumor progression genes identified in the screen (IL-6 and cysteine-rich angiogenic inducer 61) as well as potential regulators (lumican and F-box-only 6) follow similar patterns in patient glioma. The model reliably simulates key features of human glioma growth in a few days and thus could considerably increase the speed and efficacy of research on human tumor progression and preclinical drug screening. angiogenesis | animal model alternatives | glioblastoma

Public/private partners. Key factors in creating a strategic alliance for community health.

PubMed

Nelson, J C; Rashid, H; Galvin, V G; Essien, J D; Levine, L M

1999-04-01

The rapidly evolving American health system creates economic and societal incentives for public and private health organizations to collaborate. Despite the apparent benefits of collaboration, there is a paucity of information available to help local agencies develop partnerships. This study, itself a collaboration between a school of public health (SPH) and a Georgia health district, was undertaken to identify critical factors necessary to successfully initiate and sustain a public/private community health collaboration. Professional staff at the SPH conducted 26 standardized interviews involving participants from Cobb and Douglas counties Boards of Health; Promina Northwest (now known as Wellstar), a not-for-profit health system; and community stakeholders. Content analysis of each interview question was performed and comparisons were made both within each group and across groups. Trends were identified in the following key areas: vision of health care for Cobb and Douglas counties, forces driving collaboration, strengths of each organization, critical negotiating issues, and potential community gain resulting from the partnership. A shared vision between potential collaborators facilitates communication regarding strategies to achieve common goals. A previous history of working together in limited capacities allowed the partners to develop trust and respect for one another prior to entering negotiations. These factors, when taken in conjunction with each organization's strong leadership and knowledge of the community, build a strong foundation for a successful partnership.

Effects of oxygen limitation on sugar metabolism in yeasts: a continuous-culture study of the Kluyver effect.

PubMed

Weusthuis, R A; Visser, W; Pronk, J T; Scheffers, W A; van Dijken, J P

1994-04-01

Growth and metabolite formation were studied in oxygen-limited chemostat cultures of Saccharomyces cerevisiae CBS 8066 and Candida utilis CBS 621 growing on glucose or maltose at a dilution rate of 0.1 h-1. With either glucose or maltose S. cerevisiae could be grown under dual limitation of oxygen and sugar. Respiration and alcoholic fermentation occurred simultaneously and the catabolite fluxes through these processes were dependent on the magnitude of the oxygen feed. C. utilis could also be grown under dual limitation of glucose and oxygen. However, at very low oxygen feed rates (i.e. below 4 mmol l-1 h-1) growth was limited by oxygen only, as indicated by the high residual glucose concentration in the culture. In contrast to S. cerevisiae, C. utilis could not be grown anaerobically at a dilution rate of 0.1 h-1. With C. utilis absence of oxygen resulted in wash-out, despite the presence of ergosterol and Tween-80 in the growth medium. The behaviour of C. utilis with respect to maltose utilization in oxygen-limited cultures was remarkable: alcoholic fermentation did not occur and the amount of maltose metabolized was dependent on the oxygen supply. Oxygen-limited cultures of C. utilis growing on maltose always contained high residual sugar concentrations. These observations throw new light on the so-called Kluyver effect. Apparently, maltose is a non-fermentable sugar for C. utilis CBS 621, despite the fact that it can serve as a substrate for growth of this facultatively fermentative yeast. This is not due to the absence of key enzymes of alcoholic fermentation. Pyruvate decarboxylase and alcohol dehydrogenase were present at high levels in maltose-utilizing cells of C. utilis grown under oxygen limitation. It is concluded that the Kluyver effect, in C. utilis growing on maltose, results from a regulatory mechanism that prevents the sugar from being fermented. Oxygen is not a key factor in this phenomenon since under oxygen limitation alcoholic fermentation of maltose was not triggered.

Advanced Wide-Field Interferometric Microscopy for Nanoparticle Sensing and Characterization

NASA Astrophysics Data System (ADS)

Avci, Oguzhan

Nanoparticles have a key role in today's biotechnological research owing to the rapid advancement of nanotechnology. While metallic, polymer, and semiconductor based artificial nanoparticles are widely used as labels or targeted drug delivery agents, labeled and label-free detection of natural nanoparticles promise new ways for viral diagnostics and therapeutic applications. The increasing impact of nanoparticles in bio- and nano-technology necessitates the development of advanced tools for their accurate detection and characterization. Optical microscopy techniques have been an essential part of research for visualizing micron-scale particles. However, when it comes to the visualization of individual nano-scale particles, they have shown inadequate success due to the resolution and visibility limitations. Interferometric microscopy techniques have gained significant attention for providing means to overcome the nanoparticle visibility issue that is often the limiting factor in the imaging techniques based solely on the scattered light. In this dissertation, we develop a rigorous physical model to simulate the single nanoparticle optical response in a common-path wide-field interferometric microscopy (WIM) system. While the fundamental elements of the model can be used to analyze nanoparticle response in any generic wide-field imaging systems, we focus on imaging with a layered substrate (common-path interferometer) where specular reflection of illumination provides the reference light for interferometry. A robust physical model is quintessential in realizing the full potential of an optical system, and throughout this dissertation, we make use of it to benchmark our experimental findings, investigate the utility of various optical configurations, reconstruct weakly scattering nanoparticle images, as well as to characterize and discriminate interferometric nanoparticle responses. This study investigates the integration of advanced optical schemes in WIM with two main goals in mind: (i) increasing the visibility of low-index nanoscale particles via pupil function engineering, pushing the limit of sensitivity; (ii) improving the resolution of sub-diffraction-limited, low-index particle images in WIM via reconstruction strategies for shape and orientation information. We successfully demonstrate an overall ten-fold improvement in the visibility of the low-index sub-wavelength nanoparticles as well as up to two-fold extended spatial resolution of the interference-enhanced nanoparticle images. We also systematically examine the key factors that determine the signal in WIM. These factors include the particle type, size, layered substrate design, defocus and nanoparticle polarizability. We use the physical model to demonstrate how these factors determine the signal levels, and demonstrate how the layered substrate can be designed to optimize the overall signal, while defocus scan can be used to maximize it, as well as its signature can be utilized for particle discrimination purposes for both dielectric particles and resonant metallic particles. We introduce a machine learning based particle characterization algorithm that relies on supervised learning from model. The particle characterization is limited to discrimination based on nanosphere size and type in the scope of this dissertation.

Enhanced Two-Factor Authentication and Key Agreement Using Dynamic Identities in Wireless Sensor Networks

PubMed Central

Chang, I-Pin; Lee, Tian-Fu; Lin, Tsung-Hung; Liu, Chuan-Ming

2015-01-01

Key agreements that use only password authentication are convenient in communication networks, but these key agreement schemes often fail to resist possible attacks, and therefore provide poor security compared with some other authentication schemes. To increase security, many authentication and key agreement schemes use smartcard authentication in addition to passwords. Thus, two-factor authentication and key agreement schemes using smartcards and passwords are widely adopted in many applications. Vaidya et al. recently presented a two-factor authentication and key agreement scheme for wireless sensor networks (WSNs). Kim et al. observed that the Vaidya et al. scheme fails to resist gateway node bypassing and user impersonation attacks, and then proposed an improved scheme for WSNs. This study analyzes the weaknesses of the two-factor authentication and key agreement scheme of Kim et al., which include vulnerability to impersonation attacks, lost smartcard attacks and man-in-the-middle attacks, violation of session key security, and failure to protect user privacy. An efficient and secure authentication and key agreement scheme for WSNs based on the scheme of Kim et al. is then proposed. The proposed scheme not only solves the weaknesses of previous approaches, but also increases security requirements while maintaining low computational cost. PMID:26633396

Angiogenesis and microvasculature in the female reproductive organs: physiological and pathological implications.

PubMed

Shimizu, Takashi; Hoshino, Yumi; Miyazaki, Hitoshi; Sato, Eimei

2012-01-01

The female reproductive organs such as ovary, uterus, and placenta are some of the few adult tissues that exhibit regular intervals of rapid growth, and are highly vascularized and have high rates of blood flow. Angiogenesis is a process of vascular growth that is mainly limited to the reproductive system in healthy adult animals. The development of new blood vessels in the ovary and uterus is essential to guarantee the necessary supply of nutrients and hormones. The genetic and molecular mechanisms that control the development of capillary blood vessels in the reproductive organs are beginning to be elucidated. Reproductive organs contain and produce angiogenic factors which may act alone or in concert to regulate the process of vasculature. Vascular endothelial growth factors (VEGFs) and fibroblast growth factor (FGFs) are key factors for vascular system in the reproductive organs. Recent numerous studies reported several roles of VEGFs and FGFs on ovarian and uterine functions. In this review, we focus on the involvement of VEGFs and FGFs as angiogenic factors on reproductive organs and vascular therapy for diseases of reproductive organs using anti-angiogenic agents.

Pulmonary Delivery of siRNA via Polymeric Vectors as Therapies of Asthma

PubMed Central

Xie, Yuran; Merkel, Olivia M

2015-01-01

Asthma is a chronic inflammatory disease. Despite the fact that current therapies, such as the combination of inhaled corticosteroids and β2-agonists, can control the symptoms of asthma in most patients, there is still an urgent need for an alternative anti-inflammatory therapy for patients who suffer from severe asthma but lack acceptable response to conventional therapies. Many molecular factors are involved in the inflammatory process in asthma, and thus blocking the function of these factors could efficiently alleviate airway inflammation. RNA interference (RNAi) is often thought to be the answer in the search for more efficient and biocompatible treatments. However, difficulties of efficient delivery of small interference RNA (siRNA), the key factor in RNAi, to target cells and tissues has limited its clinical application. In this review, we summarize cytokines and chemokines, transcription factors, tyrosine kinases and costimulatory factors that have been reported as targets of siRNA mediated treatment in experimental asthma. Additionally, we conclude several targeted delivery systems of siRNA to specific cells such as T cells, macrophages and dendritic cells, which could potentially be applied in asthma therapy. PMID:26148454

App Usage Factor: A Simple Metric to Compare the Population Impact of Mobile Medical Apps

PubMed Central

Wyatt, Jeremy C

2015-01-01

Background One factor when assessing the quality of mobile apps is quantifying the impact of a given app on a population. There is currently no metric which can be used to compare the population impact of a mobile app across different health care disciplines. Objective The objective of this study is to create a novel metric to characterize the impact of a mobile app on a population. Methods We developed the simple novel metric, app usage factor (AUF), defined as the logarithm of the product of the number of active users of a mobile app with the median number of daily uses of the app. The behavior of this metric was modeled using simulated modeling in Python, a general-purpose programming language. Three simulations were conducted to explore the temporal and numerical stability of our metric and a simulated app ecosystem model using a simulated dataset of 20,000 apps. Results Simulations confirmed the metric was stable between predicted usage limits and remained stable at extremes of these limits. Analysis of a simulated dataset of 20,000 apps calculated an average value for the app usage factor of 4.90 (SD 0.78). A temporal simulation showed that the metric remained stable over time and suitable limits for its use were identified. Conclusions A key component when assessing app risk and potential harm is understanding the potential population impact of each mobile app. Our metric has many potential uses for a wide range of stakeholders in the app ecosystem, including users, regulators, developers, and health care professionals. Furthermore, this metric forms part of the overall estimate of risk and potential for harm or benefit posed by a mobile medical app. We identify the merits and limitations of this metric, as well as potential avenues for future validation and research. PMID:26290093

Fibrinogen Is at the Interface of Host Defense and Pathogen Virulence in Staphylococcus aureus Infection

PubMed Central

Ko, Ya-Ping; Flick, Matthew J.

2017-01-01

Fibrinogen not only plays a pivotal role in hemostasis but also serves key roles in antimicrobial host defense. As a rapidly assembled provisional matrix protein, fibrin(ogen) can function as an early line of host protection by limiting bacterial growth, suppressing dissemination of microbes to distant sites, and mediating host bacterial killing. Fibrinogen-mediated host antimicrobial activity occurs predominantly through two general mechanisms, namely, fibrin matrices functioning as a protective barrier and fibrin(ogen) directly or indirectly driving host protective immune function. The potential of fibrin to limit bacterial infection and disease has been countered by numerous bacterial species evolving and maintaining virulence factors that engage hemostatic system components within vertebrate hosts. Bacterial factors have been isolated that simply bind fibrinogen or fibrin, promote fibrin polymer formation, or promote fibrin dissolution. Staphylococcus aureus is an opportunistic gram-positive bacterium, the causative agent of a wide range of human infectious diseases, and a prime example of a pathogen exquisitely sensitive to host fibrinogen. Indeed, current data suggest fibrinogen serves as a context-dependent determinant of host defense or pathogen virulence in Staphylococcus infection whose ultimate contribution is dictated by the expression of S. aureus virulence factors, the path of infection, and the tissue microenvironment. PMID:27056151

DOD Financial Management: Improvements Needed in the Navys Audit Readiness Efforts for Fund Balance with Treasury

DTIC Science & Technology

2016-08-01

prioritization of key information technology limits management’s ability to focus audit readiness efforts on the systems with the highest risk...corrective actions for the higher-risk systems first. For an audit readiness plan for key information technology systems, the Navy provided a schedule...prioritization of key information technology systems used in the FBWT process limits management’s ability to focus audit readiness efforts on the most

'Muscle-sparing' statins: preclinical profiles and future clinical use.

PubMed

Pfefferkorn, Jeffrey A

2009-03-01

Coronary heart disease (CHD) is a leading cause of death in the US, and hypercholesterolemia is a key risk factor for this disease. The current standard of care for treating hypercholesterolemia is the use of HMG-CoA reductase inhibitors, also known as statins, which block the rate-limiting step of cholesterol biosynthesis. In widespread clinical use, statins have proven safe and effective for both primary prevention of CHD and secondary prevention of coronary events. Results from several recent clinical trials have demonstrated that increasingly aggressive cholesterol-lowering therapy might offer additional protection against CHD compared with less aggressive treatment standards. While higher doses of current statin therapies are capable of achieving these more aggressive treatment goals, in certain cases statin-induced myalgia, the muscle pain or weakness that sometimes accompanies high-dose statin therapy, limits patient compliance with a treatment regimen. To address this limitation, efforts have been undertaken to develop highly hepatoselective statins that are capable of delivering best-in-class efficacy with minimized risk of dose-limiting myalgia. In this review, the preclinical and early clinical data for these next generation statins are discussed.

Study on a linear relationship between limited pressure difference and coil current of on/off valve and its influential factors.

PubMed

Zhang, Junzhi; Lv, Chen; Yue, Xiaowei; Li, Yutong; Yuan, Ye

2014-01-01

On/off solenoid valves with PWM control are widely used in all types of vehicle electro-hydraulic control systems respecting to their desirable properties of reliable, low cost and fast acting. However, it can hardly achieve a linear hydraulic modulation by using on/off valves mainly due to the nonlinear behaviors of valve dynamics and fluid, which affects the control accuracy significantly. In this paper, a linear relationship between limited pressure difference and coil current of an on/off valve in its critical closed state is proposed and illustrated, which has a great potential to be applied to improve hydraulic control performance. The hydraulic braking system of case study is modeled. The linear correspondence between limited pressure difference and coil current of the inlet valve is simulated and further verified experimentally. Based on validated simulation models, the impacts of key parameters are researched. The limited pressure difference affected by environmental temperatures is experimentally studied, and the amended linear relation is given according to the test data. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Key feature of the catalytic cycle of TNF-α converting enzyme involves communication between distal protein sites and the enzyme catalytic core

PubMed Central

Solomon, Ariel; Akabayov, Barak; Frenkel, Anatoly; Milla, Marcos E.; Sagi, Irit

2007-01-01

Despite their key roles in many normal and pathological processes, the molecular details by which zinc-dependent proteases hydrolyze their physiological substrates remain elusive. Advanced theoretical analyses have suggested reaction models for which there is limited and controversial experimental evidence. Here we report the structure, chemistry and lifetime of transient metal–protein reaction intermediates evolving during the substrate turnover reaction of a metalloproteinase, the tumor necrosis factor-α converting enzyme (TACE). TACE controls multiple signal transduction pathways through the proteolytic release of the extracellular domain of a host of membrane-bound factors and receptors. Using stopped-flow x-ray spectroscopy methods together with transient kinetic analyses, we demonstrate that TACE's catalytic zinc ion undergoes dynamic charge transitions before substrate binding to the metal ion. This indicates previously undescribed communication pathways taking place between distal protein sites and the enzyme catalytic core. The observed charge transitions are synchronized with distinct phases in the reaction kinetics and changes in metal coordination chemistry mediated by the binding of the peptide substrate to the catalytic metal ion and product release. Here we report key local charge transitions critical for proteolysis as well as long sought evidence for the proposed reaction model of peptide hydrolysis. This study provides a general approach for gaining critical insights into the molecular basis of substrate recognition and turnover by zinc metalloproteinases that may be used for drug design. PMID:17360351

A generic concept to overcome bandgap limitations for designing highly efficient multi-junction photovoltaic cells

PubMed Central

Guo, Fei; Li, Ning; Fecher, Frank W.; Gasparini, Nicola; Quiroz, Cesar Omar Ramirez; Bronnbauer, Carina; Hou, Yi; Radmilović, Vuk V.; Radmilović, Velimir R.; Spiecker, Erdmann; Forberich, Karen; Brabec, Christoph J.

2015-01-01

The multi-junction concept is the most relevant approach to overcome the Shockley–Queisser limit for single-junction photovoltaic cells. The record efficiencies of several types of solar technologies are held by series-connected tandem configurations. However, the stringent current-matching criterion presents primarily a material challenge and permanently requires developing and processing novel semiconductors with desired bandgaps and thicknesses. Here we report a generic concept to alleviate this limitation. By integrating series- and parallel-interconnections into a triple-junction configuration, we find significantly relaxed material selection and current-matching constraints. To illustrate the versatile applicability of the proposed triple-junction concept, organic and organic-inorganic hybrid triple-junction solar cells are constructed by printing methods. High fill factors up to 68% without resistive losses are achieved for both organic and hybrid triple-junction devices. Series/parallel triple-junction cells with organic, as well as perovskite-based subcells may become a key technology to further advance the efficiency roadmap of the existing photovoltaic technologies. PMID:26177808

A generic concept to overcome bandgap limitations for designing highly efficient multi-junction photovoltaic cells.

PubMed

Guo, Fei; Li, Ning; Fecher, Frank W; Gasparini, Nicola; Ramirez Quiroz, Cesar Omar; Bronnbauer, Carina; Hou, Yi; Radmilović, Vuk V; Radmilović, Velimir R; Spiecker, Erdmann; Forberich, Karen; Brabec, Christoph J

2015-07-16

The multi-junction concept is the most relevant approach to overcome the Shockley-Queisser limit for single-junction photovoltaic cells. The record efficiencies of several types of solar technologies are held by series-connected tandem configurations. However, the stringent current-matching criterion presents primarily a material challenge and permanently requires developing and processing novel semiconductors with desired bandgaps and thicknesses. Here we report a generic concept to alleviate this limitation. By integrating series- and parallel-interconnections into a triple-junction configuration, we find significantly relaxed material selection and current-matching constraints. To illustrate the versatile applicability of the proposed triple-junction concept, organic and organic-inorganic hybrid triple-junction solar cells are constructed by printing methods. High fill factors up to 68% without resistive losses are achieved for both organic and hybrid triple-junction devices. Series/parallel triple-junction cells with organic, as well as perovskite-based subcells may become a key technology to further advance the efficiency roadmap of the existing photovoltaic technologies.

Board development in two hospitals: lessons from a demonstration.

PubMed

Kovner, A R; Ritvo, R A; Holland, T P

1997-01-01

A recently concluded demonstration project examined efforts to improve the effectiveness of nonprofit boards. This article focuses on the interventions at two participating healthcare organizations and examines the outcomes of these efforts. Changes made at the Alpha Health Care system included: reduction in the number of boards, term limits established for board members, election of new board chairs for two of the fewer boards, reduction in the size of those boards, implementation of a consent agenda, and reorganization of the boards' committee structure. Fewer changes were implemented at the Beta Hospital, where several initiatives were started but only some of which were retained by the projects' conclusion. Key factors limiting the extent of changes there were the modest interest in an active board by a new CEO and the limited investment of trustees in change. The article concludes with a discussion of lessons learned about board assessment, the use of retreats to initiate board development, and the importance of time management and CEO support to strengthen board effectiveness.

Biocatalytic coatings for air pollution control: a proof of concept study on VOC biodegradation.

PubMed

Estrada, José M; Bernal, Oscar I; Flickinger, Michael C; Muñoz, Raúl; Deshusses, Marc A

2015-02-01

Although biofilm-based biotechnologies exhibit a large potential as solutions for off-gas treatment, the high water content of biofilms often causes pollutant mass transfer limitations, which ultimately limit their widespread application. The present study reports on the proof of concept of the applicability of bioactive latex coatings for air pollution control. Toluene vapors served as a model volatile organic compound (VOC). The results showed that Pseudomonas putida F1 cells could be successfully entrapped in nanoporous latex coatings while preserving their toluene degradation activity. Bioactive latex coatings exhibited toluene specific biodegradation rates 10 times higher than agarose-based biofilms, because the thin coatings were less subject to diffusional mass transfer limitations. Drying and pollutant starvation were identified as key factors inducing a gradual deterioration of the biodegradation capacity in these innovative coatings. This study constitutes the first application of bioactive latex coatings for VOC abatement. These coatings could become promising means for air pollution control. © 2014 Wiley Periodicals, Inc.

Case Study: The Role of eLearning in Midwifery Pre-Service Education in Ghana.

PubMed

Appiagyei, Martha; Trump, Alison; Danso, Evans; Yeboah, Alex; Searle, Sarah; Carr, Catherine

The issues and challenges of implementing eLearning in pre-service health education were explored through a pilot study conducted in six nurse-midwifery education programs in Ghana. Case-based, interactive computer mediated eLearning modules, targeted to basic emergency and obstetrical signal functions, were delivered both online and offline using a free-for-use eLearning platform, skoool HE(®). Key success factors included broad stakeholder support, an established curriculum and student and tutor interest. Challenges included infrastructure limitations, large class sizes and added workloads for tutors and information technology staff. National scale up is planned.

Crisis response to schools.

PubMed

Johnson, K

2000-01-01

While community based crisis response teams offer needed resources to schools impacted by crisis, they are often not asked to help. Reports from crisis team leaders at the school shooting incidents at James W. Parker Middle School, Edinboro, Pennsylvania and Columbine High School, Littleton, Colorado are contrasted regarding utilization of community resources. Factors limiting the usefulness of community based teams include unfamiliarity with school organization, culture, and procedures. Key differences in school vs. community team precepts, decision-making, and strategic paradigms render team coordination difficult. Successful cross training presents opportunities for school-community partnership and utilization of community teams for school duty.

Planning for smallpox outbreaks

NASA Astrophysics Data System (ADS)

Ferguson, Neil M.; Keeling, Matt J.; John Edmunds, W.; Gani, Raymond; Grenfell, Bryan T.; Anderson, Roy M.; Leach, Steve

2003-10-01

Mathematical models of viral transmission and control are important tools for assessing the threat posed by deliberate release of the smallpox virus and the best means of containing an outbreak. Models must balance biological realism against limitations of knowledge, and uncertainties need to be accurately communicated to policy-makers. Smallpox poses the particular challenge that key biological, social and spatial factors affecting disease spread in contemporary populations must be elucidated largely from historical studies undertaken before disease eradication in 1979. We review the use of models in smallpox planning within the broader epidemiological context set by recent outbreaks of both novel and re-emerging pathogens.

Human resources in nursing education: a worldwide crisis.

PubMed

Potempa, Kathleen M; Redman, Richard W; Landstrom, Gay

2009-01-01

The global shortage of nurses is escalating. A key contributing factor to the production of new nurses is the growing shortage of qualified faculty. This paper explores the forces influencing the global faculty shortage, including those that increase demand and those that limit the supply of nursing faculty. The authors discuss potential solutions to the shortage, placing particular emphasis on leveraging the strengths of the profession to accelerate the progression of nurses to graduate school, the enhancement of funding for graduate education, changing the paradigm of clinical education, and the expansion of the science base for practice.

ICRH system performance during ITER-Like Wall operations at JET and the outlook for DT campaign

NASA Astrophysics Data System (ADS)

Monakhov, Igor; Blackman, Trevor; Dumortier, Pierre; Durodié, Frederic; Jacquet, Philippe; Lerche, Ernesto; Noble, Craig

2017-10-01

Performance of JET ICRH system since installation of the metal ITER-Like Wall (ILW) has been assessed statistically. The data demonstrate steady increase of the RF power coupled to plasmas over recent years with the maximum pulse-average and peak values exceeding respectively 6MW and 8MW in 2016. Analysis and extrapolation of power capabilities of conventional JET ICRH antennas is provided and key performance-limiting factors are discussed. The RF plant operational frequency options are presented highlighting the issues of efficient ICRH application within a foreseeable range of DT plasma scenarios.

Improved discrete swarm intelligence algorithms for endmember extraction from hyperspectral remote sensing images

NASA Astrophysics Data System (ADS)

Su, Yuanchao; Sun, Xu; Gao, Lianru; Li, Jun; Zhang, Bing

2016-10-01

Endmember extraction is a key step in hyperspectral unmixing. A new endmember extraction framework is proposed for hyperspectral endmember extraction. The proposed approach is based on the swarm intelligence (SI) algorithm, where discretization is used to solve the SI algorithm because pixels in a hyperspectral image are naturally defined within a discrete space. Moreover, a "distance" factor is introduced into the objective function to limit the endmember numbers which is generally limited in real scenarios, while traditional SI algorithms likely produce superabundant spectral signatures, which generally belong to the same classes. Three endmember extraction methods are proposed based on the artificial bee colony, ant colony optimization, and particle swarm optimization algorithms. Experiments with both simulated and real hyperspectral images indicate that the proposed framework can improve the accuracy of endmember extraction.

Scaling up the health workforce in the public sector: the role of government fiscal policy.

PubMed

Vujicic, Marko

2010-01-01

Health workers play a key role in increasing access to health care services. Global and country-level estimates show that staffing in many developing countries - particularly in Sub-Saharan Africa - is far leaner than needed to deliver essential health services to the population. One factor that can limit scaling up the health workforce in developing countries is the government's overall wage policy which sometimes creates restrictions on hiring in the health sector. But while there is considerable debate, the information base in this important area has been quite limited. This paper summarizes the process that determines the budget for health wages in the public sector, how it is linked to overall wage policies, and how this affects staffing in the health sector. The author draws mainly from a recent World Bank report.

Cryogenic Etching of High Aspect Ratio 400 nm Pitch Silicon Gratings.

PubMed

Miao, Houxun; Chen, Lei; Mirzaeimoghri, Mona; Kasica, Richard; Wen, Han

2016-10-01

The cryogenic process and Bosch process are two widely used processes for reactive ion etching of high aspect ratio silicon structures. This paper focuses on the cryogenic deep etching of 400 nm pitch silicon gratings with various etching mask materials including polymer, Cr, SiO 2 and Cr-on-polymer. The undercut is found to be the key factor limiting the achievable aspect ratio for the direct hard masks of Cr and SiO 2 , while the etch selectivity responds to the limitation of the polymer mask. The Cr-on-polymer mask provides the same high selectivity as Cr and reduces the excessive undercut introduced by direct hard masks. By optimizing the etching parameters, we etched a 400 nm pitch grating to ≈ 10.6 μ m depth, corresponding to an aspect ratio of ≈ 53.

Predicting performance in competitive apnea diving, part II: dynamic apnoea.

PubMed

Schagatay, Erika

2010-03-01

Part I of this series of articles identified the main physiological factors defining the limits of static apnea, while this paper reviews the factors involved when physical work is added in the dynamic distance disciplines, performed in shallow water in a swimming pool. Little scientific work has been done concerning the prerequisites and limitations of swimming with or without fins whilst breath holding to extreme limits. Apneic duration influences all competitive apnea disciplines, and can be prolonged by any means that increase gas storage or tolerance to asphyxia, or reduce metabolic rate, as reviewed in the first article. For horizontal underwater distance swimming, the main challenge is to restrict metabolism despite the work, and to direct blood flow only to areas where demand is greatest, to allow sustained function. Here, work economy, local tissue energy and oxygen stores and the anaerobic capacity of the muscles are key components. Improvements in swimming techniques and, especially in swimming with fins, equipment have already contributed to enhanced performance and may do so further. High lactate levels observed after competition swims suggest a high anaerobic component, and muscle hypoxia could ultimately limit muscle work and swimming distance. However, the frequency of syncope, especially in swimming without fins, suggests that cerebral oxygenation may often be compromised before this occurs. In these pool disciplines, safety is high and the dive can be interrupted by the competitor or safety diver within seconds. The safety routines in place during pool competitions are described.

A review of ocean color remote sensing methods and statistical techniques for the detection, mapping and analysis of phytoplankton blooms in coastal and open oceans

NASA Astrophysics Data System (ADS)

Blondeau-Patissier, David; Gower, James F. R.; Dekker, Arnold G.; Phinn, Stuart R.; Brando, Vittorio E.

2014-04-01

The need for more effective environmental monitoring of the open and coastal ocean has recently led to notable advances in satellite ocean color technology and algorithm research. Satellite ocean color sensors' data are widely used for the detection, mapping and monitoring of phytoplankton blooms because earth observation provides a synoptic view of the ocean, both spatially and temporally. Algal blooms are indicators of marine ecosystem health; thus, their monitoring is a key component of effective management of coastal and oceanic resources. Since the late 1970s, a wide variety of operational ocean color satellite sensors and algorithms have been developed. The comprehensive review presented in this article captures the details of the progress and discusses the advantages and limitations of the algorithms used with the multi-spectral ocean color sensors CZCS, SeaWiFS, MODIS and MERIS. Present challenges include overcoming the severe limitation of these algorithms in coastal waters and refining detection limits in various oceanic and coastal environments. To understand the spatio-temporal patterns of algal blooms and their triggering factors, it is essential to consider the possible effects of environmental parameters, such as water temperature, turbidity, solar radiation and bathymetry. Hence, this review will also discuss the use of statistical techniques and additional datasets derived from ecosystem models or other satellite sensors to characterize further the factors triggering or limiting the development of algal blooms in coastal and open ocean waters.

Denitrification rates in estuarine sediments of Ashtamudi, Kerala, India.

PubMed

Salahudeen, Junaid Hassan; Reshmi, R R; Anoop Krishnan, K; Ragi, M S; Vincent, Salom Gnana Thanga

2018-05-03

Estuarine sediments are important sites for denitrification, which is microbially mediated reduction of nitrate to dinitrogen that also influences global climate change by co-production of nitrous oxide, a potent greenhouse gas. Physicochemical properties and nutrients of sediment samples that influence denitrification rate were studied in Ashtamudi estuarine sediments. They were pH, electrical conductivity (EC), salinity, nitrate-nitrogen (NO 3 - -N), exchangeable ammonia (NH 3 - -N), total kjeldahl nitrogen (TKN) and organic carbon (Corg). Sediment samples were collected from six stations during summer, monsoon of 2013 and 13 stations from monsoon 2014 and summer 2015. The sedimentary denitrification potential ranged from 0.49 ± 0.05 to 4.85 ± 0.782 mmol N 2 O m -2 h -1 . Maximum denitrification was observed in S4, which is attributed to a local anthropogenic source coupled with intense rainfall episode preceding the sampling season of monsoon 2013. However, this trend was not repeated in the subsequent monsoon samples. This shows that in Ashtamudi, monsoonal effects do not influence sedimentary denitrification. Among the various environmental variables, NO 3 - -N, Corg and NH 3 -N were the key factors that influence denitrification in the Ashtamudi estuarine sediments. Among these key factors, NO 3 - -N was the limiting factor for denitrification, and hence, it is of prime importance to understand the source of NO 3 - -N that fuel denitrification in the sediments. In Ashtamudi, the concentration of NO 3 - -N in overlying water was very less, which suggests reduced nitrogen yield in the estuary from the fluvial input of Kallada River and agricultural runoff. Sedimentary NO 3 - -N correlated with denitrification which reveals that denitrification is coupled with nitrification in the sediments. This is further explained by the fact that NH 3 -N positively correlated with denitrification. The anoxic sediments were the source of ammonia for nitrous oxide production by nitrogen mineralisation. Also, the Corg in sediment samples were sufficient to support denitrification and Corg was an important factor favouring but not limiting denitrification. The results of sediment denitrification in Ashtamudi can be a model for tropical estuaries experiencing unpredictable rainfall as well as high temperature than temperate systems.

Understanding factors that influence the integration of acute malnutrition interventions into the national health system in Niger.

PubMed

Deconinck, Hedwig; Hallarou, Mahaman Elh; Pesonen, Anais; Gérard, Jean Christophe; Criel, Bart; Donnen, Philippe; Macq, Jean

2016-12-01

Since 2007 to address a high burden, integration of acute malnutrition has been promoted in Niger. This paper studies factors that influenced the integration process of acute malnutrition into the Niger national health system.We used qualitative methods of observation, key informant interviews and focus group discussions at national level, two districts and nine communities selected through convenience sampling, as well as document review. A framework approach constructed around the problem, intervention, adoption system, health system characteristics and broad context guided the analysis. Data were recorded on paper, transcribed in a descriptive record, coded by themes deduced by building on the framework and triangulated for comprehensiveness.Key facilitating factors identified were knowledge and recognition of the problem helped by accurate information; effectiveness of decentralized continuity of care; compatibility with goals, support and involvement of health actors; and leadership for aligning policies and partnerships and mobilizing resources within a favourable political context driven by multisectoral development goals. Key hindering factors identified were not fully understanding severity, causes and consequences of the problem; limited utilization and trust in health interventions; high workload, and health worker turnover and attrition; and high dependence on financial and technical support based on short-term emergency funding within a context of high demographic pressure.The study uncovered influencing factors of integrating acute malnutrition into the national health system and their complex dynamics and relationships. It elicited the need for goal-oriented strategies and alignment of health actors to achieve sustainability, and systems thinking to understand pathways that foster integration. We recommend that context-specific learning of integrating acute malnutrition may expand to include causal modelling and scenario testing to inform strategy designs. The method may also be applied to monitor progress of integrating nutrition by the multisectoral nutrition plan to guide change. © The Author 2016. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

33 CFR 165.767 - Security Zone; Manbirtee Key, Port of Manatee, Florida.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas Seventh Coast Guard District § 165.767 Security Zone; Manbirtee Key, Port of Manatee, Florida. (a) Regulated area. The following area...

Antenatal risk factors for postnatal depression: a large prospective study.

PubMed

Milgrom, Jeannette; Gemmill, Alan W; Bilszta, Justin L; Hayes, Barbara; Barnett, Bryanne; Brooks, Janette; Ericksen, Jennifer; Ellwood, David; Buist, Anne

2008-05-01

This study measured antenatal risk factors for postnatal depression in the Australian population, both singly and in combination. Risk factor data were gathered antenatally and depressive symptoms measured via the beyondblue National Postnatal Depression Program, a large prospective cohort study into perinatal mental health, conducted in all six states of Australia, and in the Australian Capital Territory, between 2002 and 2005. Pregnant women were screened for symptoms of postnatal depression at antenatal clinics in maternity services around Australia using the Edinburgh Postnatal Depression Scale (EPDS) and a psychosocial risk factor questionnaire that covered key demographic and psychosocial information. From a total of 40,333 participants, we collected antenatal EPDS data from 35,374 women and 3144 of these had a score >12 (8.9%). Subsequently, efforts were made to follow-up 22,968 women with a postnatal EPDS. Of 12,361 women who completed postnatal EPDS forms, 925 (7.5%) had an EPDS score >12. Antenatal depression together with a prior history of depression and a low level of partner support were the strongest independent antenatal predictors of a postnatal EPDS score >12. The two main limitations of the study were the use of the EPDS (a self-report screening tool) as the measure of depressive symptoms rather than a clinical diagnosis, and the rate of attrition between antenatal screening and the collection of postnatal follow-up data. Antenatal depressive symptoms appear to be as common as postnatal depressive symptoms. Previous depression, current depression/anxiety, and low partner support are found to be key antenatal risk factors for postnatal depression in this large prospective cohort, consistent with existing meta-analytic surveys. Current depression/anxiety (and to some extent social support) may be amenable to change and can therefore be targeted for intervention.

Overcoming the rate-distance limit of quantum key distribution without quantum repeaters.

PubMed

Lucamarini, M; Yuan, Z L; Dynes, J F; Shields, A J

2018-05-01

Quantum key distribution (QKD) 1,2 allows two distant parties to share encryption keys with security based on physical laws. Experimentally, QKD has been implemented via optical means, achieving key rates of 1.26 megabits per second over 50 kilometres of standard optical fibre 3 and of 1.16 bits per hour over 404 kilometres of ultralow-loss fibre in a measurement-device-independent configuration 4 . Increasing the bit rate and range of QKD is a formidable, but important, challenge. A related target, which is currently considered to be unfeasible without quantum repeaters 5-7 , is overcoming the fundamental rate-distance limit of QKD 8 . This limit defines the maximum possible secret key rate that two parties can distil at a given distance using QKD and is quantified by the secret-key capacity of the quantum channel 9 that connects the parties. Here we introduce an alternative scheme for QKD whereby pairs of phase-randomized optical fields are first generated at two distant locations and then combined at a central measuring station. Fields imparted with the same random phase are 'twins' and can be used to distil a quantum key. The key rate of this twin-field QKD exhibits the same dependence on distance as does a quantum repeater, scaling with the square-root of the channel transmittance, irrespective of who (malicious or otherwise) is in control of the measuring station. However, unlike schemes that involve quantum repeaters, ours is feasible with current technology and presents manageable levels of noise even on 550 kilometres of standard optical fibre. This scheme is a promising step towards overcoming the rate-distance limit of QKD and greatly extending the range of secure quantum communications.

Switching between nitrogen and glucose limitation: Unraveling transcriptional dynamics in Escherichia coli.

PubMed

Löffler, Michael; Simen, Joana Danica; Müller, Jan; Jäger, Günter; Laghrami, Salaheddine; Schäferhoff, Karin; Freund, Andreas; Takors, Ralf

2017-09-20

Transcriptional control under nitrogen and carbon-limitation conditions have been well analyzed for Escherichia coli. However, the transcriptional dynamics that underlie the shift in regulatory programs from nitrogen to carbon limitation is not well studied. In the present study, cells were cultivated at steady state under nitrogen (ammonia)-limited conditions then shifted to carbon (glucose) limitation to monitor changes in transcriptional dynamics. Nitrogen limitation was found to be dominated by sigma 54 (RpoN) and sigma 38 (RpoS), whereas the "housekeeping" sigma factor 70 (RpoD) and sigma 38 regulate cellular status under glucose limitation. During the transition, nitrogen-mediated control was rapidly redeemed and mRNAs that encode active uptake systems, such as ptsG and manXYZ, were quickly amplified. Next, genes encoding facilitators such as lamB were overexpressed, followed by high affinity uptake systems such as mglABC and non-specific porins such as ompF. These regulatory programs are complex and require well-equilibrated and superior control. At the metabolome level, 2-oxoglutarate is the likely component that links carbon- and nitrogen-mediated regulation by interacting with major regulatory elements. In the case of dual glucose and ammonia limitation, sigma 24 (RpoE) appears to play a key role in orchestrating these complex regulatory networks. Copyright © 2017 Elsevier B.V. All rights reserved.

Connecting the Dots: State Health Department Approaches to Addressing Shared Risk and Protective Factors Across Multiple Forms of Violence.

PubMed

Wilkins, Natalie; Myers, Lindsey; Kuehl, Tomei; Bauman, Alice; Hertz, Marci

Violence takes many forms, including intimate partner violence, sexual violence, child abuse and neglect, bullying, suicidal behavior, and elder abuse and neglect. These forms of violence are interconnected and often share the same root causes. They can also co-occur together in families and communities and can happen at the same time or at different stages of life. Often, due to a variety of factors, separate, "siloed" approaches are used to address each form of violence. However, understanding and implementing approaches that prevent and address the overlapping root causes of violence (risk factors) and promote factors that increase the resilience of people and communities (protective factors) can help practitioners more effectively and efficiently use limited resources to prevent multiple forms of violence and save lives. This article presents approaches used by 2 state health departments, the Maryland Department of Health and Mental Hygiene and the Colorado Department of Public Health and Environment, to integrate a shared risk and protective factor approach into their violence prevention work and identifies key lessons learned that may serve to inform crosscutting violence prevention efforts in other states.

Connecting the Dots: State Health Department Approaches to Addressing Shared Risk and Protective Factors Across Multiple Forms of Violence

PubMed Central

Wilkins, Natalie; Myers, Lindsey; Kuehl, Tomei; Bauman, Alice; Hertz, Marci

2018-01-01

Violence takes many forms, including intimate partner violence, sexual violence, child abuse and neglect, bullying, suicidal behavior, and elder abuse and neglect. These forms of violence are interconnected and often share the same root causes. They can also co-occur together in families and communities and can happen at the same time or at different stages of life. Often, due to a variety of factors, separate, “siloed” approaches are used to address each form of violence. However, understanding and implementing approaches that prevent and address the overlapping root causes of violence (risk factors) and promote factors that increase the resilience of people and communities (protective factors) can help practitioners more effectively and efficiently use limited resources to prevent multiple forms of violence and save lives. This article presents approaches used by 2 state health departments, the Maryland Department of Health and Mental Hygiene and the Colorado Department of Public Health and Environment, to integrate a shared risk and protective factor approach into their violence prevention work and identifies key lessons learned that may serve to inform crosscutting violence prevention efforts in other states. PMID:29189502

Factors Contributing to the Decline of Traditional Practices in Communities from the Gwallek-Kedar area, Kailash Sacred Landscape, Nepal.

PubMed

Atreya, Kishor; Pyakurel, Dipesh; Thagunna, Krishna Singh; Bhatta, Laxmi Dutt; Uprety, Yadav; Chaudhary, Ram Prasad; Oli, Bishwa Nath; Rimal, Sagar Kumar

2018-05-01

Traditional knowledge and practices are increasingly recognized in the resource conservation and management practices, however are declining in many parts of the world including Nepal. Studies on the inventory of traditional knowledge are available, albeit limited, and empirical analysis of factors contributing to the decline of traditional knowledge are negligible in Nepal. We thus initiated this study in the Nepal part of the Kailash Sacred Landscape to (i) document traditional knowledge and practices on agriculture, forest-based herbal remedy, and genetic resource conservation; and (ii) identify factors contributing to the decline of traditional practices in the communities. Data was collected during September-December 2015 through key informant interviews, focus group discussions, and households survey. The household survey data was used in binary logistic regression analysis to identify factors contributing to the decline of six key traditional practices. The study documented 56 types of traditional practices. The regressions showed that the age of the respondent, distance to the nearest forest, distance to the nearest motorable road, family members' ill health, and seasonal migration of the household members for jobs significantly influencing to the decline of the particular traditional practices, however, their effects vary within a practice and among the practices. The use of modern medicine, increasing road linkages, decreasing trend of plant resource availability, and agriculture intensification are responsible for the decline of the particular traditional practices. We recommend to recognize their significance in the governing socio-ecological systems and to link the traditional and scientific knowledge systems through policy formulations.

Community, intervention and provider support influences on implementation: reflections from a South African illustration of safety, peace and health promotion.

PubMed

van Niekerk, Ashley; Seedat, Mohamed; Kramer, Sherianne; Suffla, Shahnaaz; Bulbulia, Samed; Ismail, Ghouwa

2014-01-01

The development, implementation and evaluation of community interventions are important for reducing child violence and injuries in low- to middle-income contexts, with successful implementation critical to effective intervention outcomes. The assessment of implementation processes is required to identify the factors that influence effective implementation. This article draws on a child safety, peace and health initiative to examine key factors that enabled or hindered its implementation, in a context characterised by limited resources. A case study approach was employed. The research team was made up of six researchers and intervention coordinators, who led the development and implementation of the Ukuphepha Child Study in South Africa, and who are also the authors of this article. The study used author observations, reflections and discussions of the factors perceived to influence the implementation of the intervention. The authors engaged in an in-depth and iterative dialogic process aimed at abstracting the experiences of the intervention, with a recursive cycle of reflection and dialogue. Data were analysed utilising inductive content analysis, and categorised using classification frameworks for understanding implementation. The study highlights key factors that enabled or hindered implementation. These included the community context and concomitant community engagement processes; intervention compatibility and adaptability issues; community service provider perceptions of intervention relevance and expectations; and the intervention support system, characterised by training and mentorship support. This evaluation illustrated the complexity of intervention implementation. The study approach sought to support intervention fidelity by fostering and maintaining community endorsement and support, a prerequisite for the unfolding implementation of the intervention.

Double-Stranded RNA-Binding Protein Regulates Vascular Endothelial Growth Factor mRNA Stability, Translation, and Breast Cancer Angiogenesis▿

PubMed Central

Vumbaca, Frank; Phoenix, Kathryn N.; Rodriguez-Pinto, Daniel; Han, David K.; Claffey, Kevin P.

2008-01-01

Vascular endothelial growth factor (VEGF) is a key angiogenic factor expressed under restricted nutrient and oxygen conditions in most solid tumors. The expression of VEGF under hypoxic conditions requires transcription through activated hypoxia-inducible factor 1 (HIF-1), increased mRNA stability, and facilitated translation. This study identified double-stranded RNA-binding protein 76/NF90 (DRBP76/NF90), a specific isoform of the DRBP family, as a VEGF mRNA-binding protein which plays a key role in VEGF mRNA stability and protein synthesis under hypoxia. The DRBP76/NF90 protein binds to a human VEGF 3′ untranslated mRNA stability element. RNA interference targeting the DRBP76/NF90 isoform limited hypoxia-inducible VEGF mRNA and protein expression with no change in HIF-1-dependent transcriptional activity. Stable repression of DRBP76/NF90 in MDA-MB-435 breast cancer cells demonstrated reduced polysome-associated VEGF mRNA levels under hypoxic conditions and reduced mRNA stability. Transient overexpression of the DRBP76/NF90 protein increased both VEGF mRNA and protein levels synthesized under normoxic and hypoxic conditions. Cells with stable repression of the DRBP76/NF90 isoform showed reduced tumorigenic and angiogenic potential in an orthotopic breast tumor model. These data demonstrate that the DRBP76/NF90 isoform facilitates VEGF expression by promoting VEGF mRNA loading onto polysomes and translation under hypoxic conditions, thus promoting breast cancer growth and angiogenesis in vivo. PMID:18039850

Community, intervention and provider support influences on implementation: reflections from a South African illustration of safety, peace and health promotion

PubMed Central

2014-01-01

Background The development, implementation and evaluation of community interventions are important for reducing child violence and injuries in low- to middle-income contexts, with successful implementation critical to effective intervention outcomes. The assessment of implementation processes is required to identify the factors that influence effective implementation. This article draws on a child safety, peace and health initiative to examine key factors that enabled or hindered its implementation, in a context characterised by limited resources. Methods A case study approach was employed. The research team was made up of six researchers and intervention coordinators, who led the development and implementation of the Ukuphepha Child Study in South Africa, and who are also the authors of this article. The study used author observations, reflections and discussions of the factors perceived to influence the implementation of the intervention. The authors engaged in an in-depth and iterative dialogic process aimed at abstracting the experiences of the intervention, with a recursive cycle of reflection and dialogue. Data were analysed utilising inductive content analysis, and categorised using classification frameworks for understanding implementation. Results The study highlights key factors that enabled or hindered implementation. These included the community context and concomitant community engagement processes; intervention compatibility and adaptability issues; community service provider perceptions of intervention relevance and expectations; and the intervention support system, characterised by training and mentorship support. Conclusions This evaluation illustrated the complexity of intervention implementation. The study approach sought to support intervention fidelity by fostering and maintaining community endorsement and support, a prerequisite for the unfolding implementation of the intervention. PMID:25081088

IMBLMS phase B4, additional tasks 5.0. Microbial identification system

NASA Technical Reports Server (NTRS)

1971-01-01

A laboratory study was undertaken to provide simplified procedures leading to the presumptive identification (I/D) of defined microorganisms on-board an orbiting spacecraft. Identifications were to be initiated by nonprofessional bacteriologists, (crew members) on a contingency basis only. Key objectives/constraints for this investigation were as follows:(1) I/D procedures based on limited, defined diagnostic tests, (2) testing oriented about ten selected microorganisms, (3) provide for definitive I/D key and procedures per selected organism, (4) define possible occurrences of false positives for the resulting I/D key by search of the appropriate literature, and (5) evaluation of the I/D key and procedure through a limited field trial on randomly selected subjects using the I/D key.

Metal contamination disturbs biochemical and microbial properties of calcareous agricultural soils of the Mediterranean area.

PubMed

de Santiago-Martín, Ana; Cheviron, Natalie; Quintana, Jose R; González, Concepción; Lafuente, Antonio L; Mougin, Christian

2013-04-01

Mediterranean climate characteristics and carbonate are key factors governing soil heavy-metal accumulation, and low organic matter (OM) content could limit the ability of microbial populations to cope with resulting stress. We studied the effects of metal contamination on a combination of biological parameters in soils having these characteristics. With this aim, soils were spiked with a mixture of cadmium, copper, lead, and zinc, at the two limit values proposed by current European legislation, and incubated for ≤12 months. Then we measured biochemical (phosphatase, urease, β-galactosidase, arylsulfatase, and dehydrogenase activities) and microbial (fungal and bacterial DNA concentration by quantitative polymerase chain reaction) parameters. All of the enzyme activities were strongly affected by metal contamination and showed the following inhibition sequence: phosphatase (30-64 %) < arylsulfatase (38-97 %) ≤ urease (1-100 %) ≤ β-galactosidase (30-100 %) < dehydrogenase (69-100 %). The high variability among soils was attributed to the different proportion of fine mineral fraction, OM, crystalline iron oxides, and divalent cations in soil solution. The decrease of fungal DNA concentration in metal-spiked soils was negligible, whereas the decrease of bacterial DNA was ~1-54 % at the lowest level and 2-69 % at the highest level of contamination. The lowest bacterial DNA decrease occurred in soils with the highest OM, clay, and carbonate contents. Finally, regarding the strong inhibition of the biological parameters measured and the alteration of the fungal/bacterial DNA ratio, we provide strong evidence that disturbance on the system, even within the limiting values of contamination proposed by the current European Directive, could alter key soil processes. These limiting values should be established according to soil characteristics and/or revised when contamination is produced by a mixture of heavy metals.

MYB10 and MYB72 are required for growth under iron-limiting conditions.

PubMed

Palmer, Christine M; Hindt, Maria N; Schmidt, Holger; Clemens, Stephan; Guerinot, Mary Lou

2013-11-01

Iron is essential for photosynthesis and is often a limiting nutrient for plant productivity. Plants respond to conditions of iron deficiency by increasing transcript abundance of key genes involved in iron homeostasis, but only a few regulators of these genes have been identified. Using genome-wide expression analysis, we searched for transcription factors that are induced within 24 hours after transferring plants to iron-deficient growth conditions. Out of nearly 100 transcription factors shown to be up-regulated, we identified MYB10 and MYB72 as the most highly induced transcription factors. Here, we show that MYB10 and MYB72 are functionally redundant and are required for plant survival in alkaline soil where iron availability is greatly restricted. myb10myb72 double mutants fail to induce transcript accumulation of the nicotianamine synthase gene NAS4. Both myb10myb72 mutants and nas4-1 mutants have reduced iron concentrations, chlorophyll levels, and shoot mass under iron-limiting conditions, indicating that these genes are essential for proper plant growth. The double myb10myb72 mutant also showed nickel and zinc sensitivity, similar to the nas4 mutant. Ectopic expression of NAS4 rescues myb10myb72 plants, suggesting that loss of NAS4 is the primary defect in these plants and emphasizes the importance of nicotianamine, an iron chelator, in iron homeostasis. Overall, our results provide evidence that MYB10 and MYB72 act early in the iron-deficiency regulatory cascade to drive gene expression of NAS4 and are essential for plant survival under iron deficiency.

Plants in alpine environments

USGS Publications Warehouse

Germino, Matthew J.

2014-01-01

Alpine and subalpine plant species are of special interest in ecology and ecophysiology because they represent life at the climate limit and changes in their relative abundances can be a bellwether for climate-change impacts. Perennial life forms dominate alpine plant communities, and their form and function reflect various avoidance, tolerance, or resistance strategies to interactions of cold temperature, radiation, wind, and desiccation stresses that prevail in the short growing seasons common (but not ubiquitous) in alpine areas. Plant microclimate is typically uncoupled from the harsh climate of the alpine, often leading to substantially warmer plant temperatures than air temperatures recorded by weather stations. Low atmospheric pressure is the most pervasive, fundamental, and unifying factor for alpine environments, but the resulting decrease in partial pressure of CO2 does not significantly limit carbon gain by alpine plants. Factors such as tree islands and topographic features create strong heterogeneous mosaics of microclimate and snow cover that are reflected in plant community composition. Factors affecting tree establishment and growth and formation of treeline are key to understanding alpine ecology. Carbohydrate and other carbon storage, rapid development in a short growing season, and physiological function at low temperature are prevailing attributes of alpine plants. A major contemporary research theme asks whether chilling at alpine-treeline affects the ability of trees to assimilate the growth resources and particularly carbon needed for growth or whether the growth itself is limited by the alpine environment. Alpine areas tend to be among the best conserved, globally, yet they are increasingly showing response to a range of anthropogenic impacts, such as atmospheric deposition.

Factors affecting construction performance: exploratory factor analysis

NASA Astrophysics Data System (ADS)

Soewin, E.; Chinda, T.

2018-04-01

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

Challenges in conducting a community-based influenza vaccine trial in a rural community in northern India.

PubMed

Kumar, Rakesh; Amarchand, Ritvik; Narayan, Venkatesh Vinayak; Saha, Siddhartha; Lafond, Kathryn E; Kapoor, Suresh K; Dar, Lalit; Jain, Seema; Krishnan, Anand

2018-04-04

Evidence on influenza vaccine effectiveness from low and middle countries (LMICs) is limited due to limited institutional capacities; lack of adequate resources; and lack of interest by ministries of health for influenza vaccine introduction. There are concerns that the highest ethical standards will be compromised during trials in LMICs leading to mistrust of clinical trials. These factors pose regulatory and operational challenges to researchers in these countries. We conducted a community-based vaccine trial to assess the efficacy of live attenuated influenza vaccine and inactivated influenza vaccine in rural north India. Key regulatory challenges included obtaining regulatory approvals, reporting of adverse events, and compensating subjects for trial-related injuries; all of which were required to be completed in a timely fashion. Key operational challenges included obtaining audio-visual consent; maintaining a low attrition rate; and administering vaccines during a narrow time period before the influenza season, and under extreme heat. We overcame these challenges through advanced planning, and sustaining community engagement. We adapted the trial procedures to cope with field conditions by conducting mock vaccine camps; and planned for early morning vaccination to mitigate threats to the cold chain. These lessons may help investigators to confront similar challenges in other LMICs.

Rituximab biosimilars.

PubMed

Vital, Edward M; Kay, Jonathan; Emery, Paul

2013-07-01

Rituximab is a monoclonal antibody targeting CD20, used to treat B cell malignancies and B cell-mediated autoimmune diseases. Rituximab has the largest market of any monoclonal antibody therapeutic. Its patent will expire within the next few years and several manufacturers have already produced or are developing rituximab biosimilars that aim to match the innovator rituximab as closely as possible. In this review, we discuss key factors that determine the efficacy of rituximab therapy, potential technical challenges in the manufacture and evaluation of biosimilars, regulatory considerations regarding the review and approval of biosimilars, and the current status of biosimilar rituximab development by various manufacturers. Due to the nature of the topic, literature searches included conference abstracts, regulatory and industry websites as well as peer reviewed literature. Cost is a key limitation of current biologics usage and there is a political impetus to the licensing of biosimilars. Concerns regarding potential dissimilarities of biosimilars are legitimate, but surmountable with techniques for in vitro, in vivo and clinical testing and more clearly defined regulatory requirements. These should provide reassurance to prescribers. However, the cost of manufacturing and licensing a biosimilar remains high and the reduction in cost may be more limited than for a non-biologic small molecule drug and its generic version. This cost reduction will be critical to the impact and use of rituximab biosimilars.

On the key role of droughts in the dynamics of summer fires in Mediterranean Europe.

PubMed

Turco, Marco; von Hardenberg, Jost; AghaKouchak, Amir; Llasat, Maria Carmen; Provenzale, Antonello; Trigo, Ricardo M

2017-03-06

Summer fires frequently rage across Mediterranean Europe, often intensified by high temperatures and droughts. According to the state-of-the-art regional fire risk projections, in forthcoming decades climate effects are expected to become stronger and possibly overcome fire prevention efforts. However, significant uncertainties exist and the direct effect of climate change in regulating fuel moisture (e.g. warmer conditions increasing fuel dryness) could be counterbalanced by the indirect effects on fuel structure (e.g. warmer conditions limiting fuel amount), affecting the transition between climate-driven and fuel-limited fire regimes as temperatures increase. Here we analyse and model the impact of coincident drought and antecedent wet conditions (proxy for the climatic factor influencing total fuel and fine fuel structure) on the summer Burned Area (BA) across all eco-regions in Mediterranean Europe. This approach allows BA to be linked to the key drivers of fire in the region. We show a statistically significant relationship between fire and same-summer droughts in most regions, while antecedent climate conditions play a relatively minor role, except in few specific eco-regions. The presented models for individual eco-regions provide insights on the impacts of climate variability on BA, and appear to be promising for developing a seasonal forecast system supporting fire management strategies.

Genome Sequences and Phylogenetic Analysis of K88- and F18-Positive Porcine Enterotoxigenic Escherichia coli

PubMed Central

Shepard, Sara M.; Danzeisen, Jessica L.; Isaacson, Richard E.; Seemann, Torsten; Achtman, Mark

2012-01-01

Porcine enterotoxigenic Escherichia coli (ETEC) continues to result in major morbidity and mortality in the swine industry via postweaning diarrhea. The key virulence factors of ETEC strains, their serotypes, and their fimbrial components have been well studied. However, most studies to date have focused on plasmid-encoded traits related to colonization and toxin production, and the chromosomal backgrounds of these strains have been largely understudied. Here, we generated the genomic sequences of K88-positive and F18-positive porcine ETEC strains and examined the phylogenetic distribution of clinical porcine ETEC strains and their plasmid-associated genetic content. The genomes of porcine ETEC strains UMNK88 and UMNF18 were both found to contain remarkable plasmid complements containing known virulence factors, potential novel virulence factors, and antimicrobial resistance-associated elements. The chromosomes of these strains also possessed several unique genomic islands containing hypothetical genes with similarity to classical virulence factors, although phage-associated genomic islands dominated the accessory genomes of these strains. Phylogenetic analysis of 78 clinical isolates associated with neonatal and porcine diarrhea revealed that a limited subset of porcine ETEC lineages exist that generally contain common toxin and fimbrial profiles, with many of the isolates belonging to the ST10, ST23, and ST169 multilocus sequencing types. These lineages were generally distinct from existing human ETEC database isolates. Overall, most porcine ETEC strains appear to have emerged from a limited subset of E. coli lineages that either have an increased propensity to carry plasmid-encoded virulence factors or have the appropriate ETEC core genome required for virulence. PMID:22081385

RRM2 induces NF-{kappa}B-dependent MMP-9 activation and enhances cellular invasiveness

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

Duxbury, Mark S.; Whang, Edward E.

2007-03-02

Ribonucleotide reductase is a dimeric enzyme that catalyzes conversion of ribonucleotide 5'-diphosphates to their 2'-deoxynucleotide forms, a rate-limiting step in the production of 2'-deoxyribonucleoside 5'-triphosphates required for DNA synthesis. The ribonucleotide reductase M2 subunit (RRM2) is a determinant of malignant cellular behavior in a range of human cancers. We examined the effect of RRM2 overexpression on pancreatic adenocarcinoma cellular invasiveness and nuclear factor-{kappa}B (NF-{kappa}B) transcription factor activity. RRM2 overexpression increases pancreatic adenocarcinoma cellular invasiveness and MMP-9 expression in a NF-{kappa}B-dependent manner. RNA interference (RNAi)-mediated silencing of RRM2 expression attenuates cellular invasiveness and NF-{kappa}B activity. NF-{kappa}B is a key mediator ofmore » the invasive phenotypic changes induced by RRM2 overexpression.« less

Geospatial modeling approach to monument construction using Michigan from A.D. 1000-1600 as a case study.

PubMed

Howey, Meghan C L; Palace, Michael W; McMichael, Crystal H

2016-07-05

Building monuments was one way that past societies reconfigured their landscapes in response to shifting social and ecological factors. Understanding the connections between those factors and monument construction is critical, especially when multiple types of monuments were constructed across the same landscape. Geospatial technologies enable past cultural activities and environmental variables to be examined together at large scales. Many geospatial modeling approaches, however, are not designed for presence-only (occurrence) data, which can be limiting given that many archaeological site records are presence only. We use maximum entropy modeling (MaxEnt), which works with presence-only data, to predict the distribution of monuments across large landscapes, and we analyze MaxEnt output to quantify the contributions of spatioenvironmental variables to predicted distributions. We apply our approach to co-occurring Late Precontact (ca. A.D. 1000-1600) monuments in Michigan: (i) mounds and (ii) earthwork enclosures. Many of these features have been destroyed by modern development, and therefore, we conducted archival research to develop our monument occurrence database. We modeled each monument type separately using the same input variables. Analyzing variable contribution to MaxEnt output, we show that mound and enclosure landscape suitability was driven by contrasting variables. Proximity to inland lakes was key to mound placement, and proximity to rivers was key to sacred enclosures. This juxtaposition suggests that mounds met local needs for resource procurement success, whereas enclosures filled broader regional needs for intergroup exchange and shared ritual. Our study shows how MaxEnt can be used to develop sophisticated models of past cultural processes, including monument building, with imperfect, limited, presence-only data.

Evaluating the Intervention-Based Evidence Surrounding the Causal Role of Breakfast on Markers of Weight Management, with Specific Focus on Breakfast Composition and Size1234

PubMed Central

Leidy, Heather J; Gwin, Jess A; Roenfeldt, Connor A; Zino, Adam Z; Shafer, Rebecca S

2016-01-01

Nutritional strategies are vitally needed to aid in the management of obesity. Cross-sectional and epidemiologic studies consistently demonstrate that breakfast consumption is strongly associated with a healthy body weight. However, the intervention-based long-term evidence supporting a causal role of breakfast consumption is quite limited and appears to be influenced by several key dietary factors, such as dietary protein, fiber, and energy content. This article provides a comprehensive review of the intervention-based literature that examines the effects of breakfast consumption on markers of weight management and daily food intake. In addition, specific focus on the composition and size (i.e., energy content) of the breakfast meal is included. Overall, there is limited evidence supporting (or refuting) the daily consumption of breakfast for body weight management and daily food intake. In terms of whether the type of breakfast influences these outcomes, there is accumulating evidence supporting the consumption of increased dietary protein and fiber content at breakfast, as well as the consumption of more energy during the morning hours. However, the majority of the studies that manipulated breakfast composition and content did not control for habitual breakfast behaviors, nor did these studies include a breakfast-skipping control arm. Thus, it is unclear whether the addition of these types of breakfast plays a causal role in weight management. Future research, including large randomized controlled trials of longer-term (i.e., ≥6 mo) duration with a focus on key dietary factors, is critical to begin to assess whether breakfast recommendations are appropriate for the prevention and/or treatment of obesity. PMID:27184285

Misoprostol for the prevention of postpartum hemorrhage during home births in rural Lao PDR: establishing a pilot program for community distribution.

PubMed

Durham, Jo; Phengsavanh, Alongkone; Sychareun, Vanphanom; Hose, Isaac; Vongxay, Viengnakhone; Xaysomphou, Douangphachanh; Rickart, Keith

2018-01-01

The purpose of this study was to gather the necessary data to support the design and implementation of a pilot program for women who are unable to deliver in a healthcare facility in the Lao People's Democratic Republic (PDR), by using community distribution of misoprostol to prevent postpartum hemorrhage (PPH). The study builds on an earlier research that demonstrated both support and need for community-based distribution of misoprostol in Lao PDR. This qualitative study identified acceptability of misoprostol and healthcare system needs at varying levels to effectively distribute misoprostol to women with limited access to facility-based birthing. Interviews (n=25) were undertaken with stakeholders at the central, provincial, and district levels and with community members in five rural communities in Oudomxay, a province with high rates of maternal mortality. Focus group discussions (n=5) were undertaken in each community. Respondents agreed that PPH was the major cause of preventable maternal mortality with community distribution of misoprostol an acceptable and feasible interim preventative solution. Strong leadership, training, and community mobilization were identified as critical success factors. While several participants preferred midwives to distribute misoprostol, given the limited availability of midwives, there was a general agreement that village health workers or other lower level workers could safely administer misoprostol. Many key stakeholders, including women themselves, considered that these community-level staff may be able to provide misoprostol to women for self-administration, as long as appropriate education on its use was included. The collected data also helped identify appropriate educational messages and key indicators for monitoring and evaluation for a pilot program. The findings strengthen the case for a pilot program of community distribution of misoprostol to prevent PPH in remote communities where women have limited access to a health facility and highlight the key areas of consideration in developing such a program.

Misoprostol for the prevention of postpartum hemorrhage during home births in rural Lao PDR: establishing a pilot program for community distribution

PubMed Central

Durham, Jo; Phengsavanh, Alongkone; Sychareun, Vanphanom; Hose, Isaac; Vongxay, Viengnakhone; Xaysomphou, Douangphachanh; Rickart, Keith

2018-01-01

Purpose The purpose of this study was to gather the necessary data to support the design and implementation of a pilot program for women who are unable to deliver in a healthcare facility in the Lao People’s Democratic Republic (PDR), by using community distribution of misoprostol to prevent postpartum hemorrhage (PPH). The study builds on an earlier research that demonstrated both support and need for community-based distribution of misoprostol in Lao PDR. Methods This qualitative study identified acceptability of misoprostol and healthcare system needs at varying levels to effectively distribute misoprostol to women with limited access to facility-based birthing. Interviews (n=25) were undertaken with stakeholders at the central, provincial, and district levels and with community members in five rural communities in Oudomxay, a province with high rates of maternal mortality. Focus group discussions (n=5) were undertaken in each community. Results Respondents agreed that PPH was the major cause of preventable maternal mortality with community distribution of misoprostol an acceptable and feasible interim preventative solution. Strong leadership, training, and community mobilization were identified as critical success factors. While several participants preferred midwives to distribute misoprostol, given the limited availability of midwives, there was a general agreement that village health workers or other lower level workers could safely administer misoprostol. Many key stakeholders, including women themselves, considered that these community-level staff may be able to provide misoprostol to women for self-administration, as long as appropriate education on its use was included. The collected data also helped identify appropriate educational messages and key indicators for monitoring and evaluation for a pilot program. Conclusion The findings strengthen the case for a pilot program of community distribution of misoprostol to prevent PPH in remote communities where women have limited access to a health facility and highlight the key areas of consideration in developing such a program. PMID:29785142

Research in image management and access

NASA Technical Reports Server (NTRS)

Vondran, Raymond F.; Barron, Billy J.

1993-01-01

Presently, the problem of over-all library system design has been compounded by the accretion of both function and structure to a basic framework of requirements. While more device power has led to increased functionality, opportunities for reducing system complexity at the user interface level have not always been pursued with equal zeal. The purpose of this book is therefore to set forth and examine these opportunities, within the general framework of human factors research in man-machine interfaces. Human factors may be viewed as a series of trade-off decisions among four polarized objectives: machine resources and user specifications; functionality and user requirements. In the past, a limiting factor was the availability of systems. However, in the last two years, over one hundred libraries supported by many different software configurations have been added to the Internet. This document includes a statistical analysis of human responses to five Internet library systems by key features, development of the ideal online catalog system, and ideal online catalog systems for libraries and information centers.

Factors Affecting Quality of Life for Korean American Cancer Survivors: An Integrative Review.

PubMed

Yoon, Hyojin; Chatters, Linda; Kao, Tsui-Sui; Saint-Arnault, Denise; Northouse, Laurel

2016-05-01

Understanding of Korean American cancer survivors' quality of life (QOL) within a cultural context is limited. This article examines factors associated with the QOL of Korean American cancer survivors.
. A systematic literature search was conducted of PubMed, CINAHL®, Google Scholar, and EBSCO databases from January 2000 to January 2014.
. The studies were assessed for the relevance to the purpose of the review. Each study was rated on a two-point scale using an 11-item quality criteria checklist.
. The 13 studies that met the criteria for inclusion included 7 descriptive, 5 qualitative, and 1 mixed-method. 
. Social support, communication, and acculturation were key factors associated with Korean Americans' QOL. Cultural differences were evident for Korean Americans versus other Asian American ethnic groups.
. More innovative and culturally driven research is needed to understand each minority group's cultural barriers, as well as to improve cancer survivors' QOL. Improving the doctor-patient relationship is critical to promoting better cancer experiences for Korean American cancer survivors.

Assessing cognitive processes related to insomnia: A review and measurement guide for Harvey's cognitive model for the maintenance of insomnia.

PubMed

Hiller, Rachel M; Johnston, Anna; Dohnt, Hayley; Lovato, Nicole; Gradisar, Michael

2015-10-01

Cognitive processes play an important role in the maintenance, and treatment of sleep difficulties, including insomnia. In 2002, a comprehensive model was proposed by Harvey. Since its inception the model has received >300 citations, and provided researchers and clinicians with a framework for understanding and treating insomnia. The aim of this review is two-fold. First, we review the current literature investigating each factor proposed in Harvey's cognitive model of insomnia. Second, we summarise the psychometric properties of key measures used to assess the model's factors and mechanisms. From these aims, we demonstrate both strengths and limitations of the current knowledge of appropriate measurements associated with the model. This review aims to stimulate and guide future research in this area; and provide an understanding of the resources available to measure, target, and resolve cognitive factors that may maintain chronic insomnia. Copyright © 2014 Elsevier Ltd. All rights reserved.

Service quality in healthcare institutions: establishing the gaps for policy action.

PubMed

Abuosi, Aaron A; Atinga, Roger A

2013-01-01

The authors seek to examine two key issues: to assess patients' hospital service quality perceptions and expectation using SERVQUAL; and to outline the distinct concepts used to assess patient perceptions. Questionnaires were administered to 250 patients on admission and follow-up visits. The 22 paired SERVQUAL expectation and perception items were adopted. Repeated t-measures and factor analysis with Varimax rotation were used to analyse data. Results showed that patient expectations were not being met during medical treatment. Perceived service quality was rated lower than expectations for all variables. The mean difference between perceptions and expectations was statistically significant. Contrary to the SERVQUAL five-factor model, four service-quality factors were identified in the study. Findings have practical implications for hospital managers who should consider stepping up staffing levels backed by client-centred training programmes to help clinicians deliver care to patients' expectations. Limited studies are tailored towards patients' service-quality perception and expectation in Ghanaian hospitals. The findings therefore provide valuable information for policy and practice.

Factors influencing motivation and retention of primary healthcare workers in the rural areas of Oyo State, Nigeria.

PubMed

Jegede, Ayodele S; Adejumo, Prisca; Ushie, Boniface Ayanbekongshie

2013-01-01

Limited data exist on retention of primary healthcare (PHC) staff in rural areas, crippling the already fragile healthcare systems in Nigeria. This study investigated why PHC staff would or would not want to work in rural areas and how they could be retained. Four hundred and twelve (412) health workers and caregivers, and 21 key informants were interviewed in Ona-Ara LGA. Logistic regression statistics was used to analyse quantitative data and narrative for qualitative data. There was no significant factor influencing health workers' unwillingness to work in rural areas and, relationship between their demographic characteristics and perceived reasons to do so. Combined factors influencing PHC workers' willingness to work in rural areas influenced use of PHC. Financial and non-financial incentives are responsible for workers' motivation to work in rural areas. The mal-distribution of health facilities and health workers between urban and rural areas must be addressed. Copyright © 2013 Longwoods Publishing.

Leading God's People: Perceptions of Influence Among African-American Pastors.

PubMed

Harmon, Brook E; Strayhorn, Shaila; Webb, Benjamin L; Hébert, James R

2018-01-31

Religious leaders, particularly African-American pastors, are believed to play a key role in addressing health disparities. Despite the role African-American pastors may play in improving health, there is limited research on pastoral influence. The purpose of this study was to examine African-American pastors' perceptions of their influence in their churches and communities. In-depth interviews were conducted with 30 African-American pastors and analyzed using a grounded theory approach. Three themes emerged: the historical role of the church; influence as contextual, with pastors using comparisons with other pastors to describe their ability to be influential; and a reciprocal relationship existing such that pastors are influenced by factors such as God and their community while these factors also aid them in influencing others. A conceptual model of pastoral influence was created using data from this study and others to highlight factors that influence pastors, potential outcomes and moderators as well as the reciprocal nature of pastoral influence.

Physiological limits to endurance exercise performance: influence of sex

PubMed Central

2017-01-01

Abstract This brief review summarizes factors associated with elite endurance performance, trends in distance running training, and participation by men and more recently women. It is framed in the context of key ideas about the physiological determinants of endurance performance but also touches on some historical and sociological factors relevant to the overall topic. Historical trends that served to increase women's participation in elite endurance events are also discussed as is the role of increased volume and intensity of training. The rapid improvement in women's world record marathon times in the 1970s and 80s are emblematic of these trends and represent a combination of increased training volume and intensity and more competitive opportunities. This occurred as bans on participation by women in endurance events were lifted. For men these same trends evolved over a much longer time frame. The main physiological factor responsible for 10–12% slower times in women compared to men at the elite level are also considered and probably centre aroundV˙O2 max . PMID:28028816

Neural Precursor-Derived Pleiotrophin Mediates Subventricular Zone Invasion by Glioma.

PubMed

Qin, Elizabeth Y; Cooper, Dominique D; Abbott, Keene L; Lennon, James; Nagaraja, Surya; Mackay, Alan; Jones, Chris; Vogel, Hannes; Jackson, Peter K; Monje, Michelle

2017-08-24

The lateral ventricle subventricular zone (SVZ) is a frequent and consequential site of pediatric and adult glioma spread, but the cellular and molecular mechanisms mediating this are poorly understood. We demonstrate that neural precursor cell (NPC):glioma cell communication underpins this propensity of glioma to colonize the SVZ through secretion of chemoattractant signals toward which glioma cells home. Biochemical, proteomic, and functional analyses of SVZ NPC-secreted factors revealed the neurite outgrowth-promoting factor pleiotrophin, along with required binding partners SPARC/SPARCL1 and HSP90B, as key mediators of this chemoattractant effect. Pleiotrophin expression is strongly enriched in the SVZ, and pleiotrophin knock down starkly reduced glioma invasion of the SVZ in the murine brain. Pleiotrophin, in complex with the binding partners, activated glioma Rho/ROCK signaling, and ROCK inhibition decreased invasion toward SVZ NPC-secreted factors. These findings demonstrate a pathogenic role for NPC:glioma interactions and potential therapeutic targets to limit glioma invasion. PAPERCLIP. Copyright © 2017 Elsevier Inc. All rights reserved.

High-resolution mapping of transcription factor binding sites on native chromatin

PubMed Central

Kasinathan, Sivakanthan; Orsi, Guillermo A.; Zentner, Gabriel E.; Ahmad, Kami; Henikoff, Steven

2014-01-01

Sequence-specific DNA-binding proteins including transcription factors (TFs) are key determinants of gene regulation and chromatin architecture. Formaldehyde cross-linking and sonication followed by Chromatin ImmunoPrecipitation (X-ChIP) is widely used for profiling of TF binding, but is limited by low resolution and poor specificity and sensitivity. We present a simple protocol that starts with micrococcal nuclease-digested uncross-linked chromatin and is followed by affinity purification of TFs and paired-end sequencing. The resulting ORGANIC (Occupied Regions of Genomes from Affinity-purified Naturally Isolated Chromatin) profiles of Saccharomyces cerevisiae Abf1 and Reb1 provide highly accurate base-pair resolution maps that are not biased toward accessible chromatin, and do not require input normalization. We also demonstrate the high specificity of our method when applied to larger genomes by profiling Drosophila melanogaster GAGA Factor and Pipsqueak. Our results suggest that ORGANIC profiling is a widely applicable high-resolution method for sensitive and specific profiling of direct protein-DNA interactions. PMID:24336359

Miscoding-induced stalling of substrate translocation on the bacterial ribosome.

PubMed

Alejo, Jose L; Blanchard, Scott C

2017-10-10

Directional transit of the ribosome along the messenger RNA (mRNA) template is a key determinant of the rate and processivity of protein synthesis. Imaging of the multistep translocation mechanism using single-molecule FRET has led to the hypothesis that substrate movements relative to the ribosome resolve through relatively long-lived late intermediates wherein peptidyl-tRNA enters the P site of the small ribosomal subunit via reversible, swivel-like motions of the small subunit head domain within the elongation factor G (GDP)-bound ribosome complex. Consistent with translocation being rate-limited by recognition and productive engagement of peptidyl-tRNA within the P site, we now show that base-pairing mismatches between the peptidyl-tRNA anticodon and the mRNA codon dramatically delay this rate-limiting, intramolecular process. This unexpected relationship between aminoacyl-tRNA decoding and translocation suggests that miscoding antibiotics may impact protein synthesis by impairing the recognition of peptidyl-tRNA in the small subunit P site during EF-G-catalyzed translocation. Strikingly, we show that elongation factor P (EF-P), traditionally known to alleviate ribosome stalling at polyproline motifs, can efficiently rescue translocation defects arising from miscoding. These findings help reveal the nature and origin of the rate-limiting steps in substrate translocation on the bacterial ribosome and indicate that EF-P can aid in resuming translation elongation stalled by miscoding errors.

Miscoding-induced stalling of substrate translocation on the bacterial ribosome

PubMed Central

Alejo, Jose L.; Blanchard, Scott C.

2017-01-01

Directional transit of the ribosome along the messenger RNA (mRNA) template is a key determinant of the rate and processivity of protein synthesis. Imaging of the multistep translocation mechanism using single-molecule FRET has led to the hypothesis that substrate movements relative to the ribosome resolve through relatively long-lived late intermediates wherein peptidyl-tRNA enters the P site of the small ribosomal subunit via reversible, swivel-like motions of the small subunit head domain within the elongation factor G (GDP)-bound ribosome complex. Consistent with translocation being rate-limited by recognition and productive engagement of peptidyl-tRNA within the P site, we now show that base-pairing mismatches between the peptidyl-tRNA anticodon and the mRNA codon dramatically delay this rate-limiting, intramolecular process. This unexpected relationship between aminoacyl-tRNA decoding and translocation suggests that miscoding antibiotics may impact protein synthesis by impairing the recognition of peptidyl-tRNA in the small subunit P site during EF-G–catalyzed translocation. Strikingly, we show that elongation factor P (EF-P), traditionally known to alleviate ribosome stalling at polyproline motifs, can efficiently rescue translocation defects arising from miscoding. These findings help reveal the nature and origin of the rate-limiting steps in substrate translocation on the bacterial ribosome and indicate that EF-P can aid in resuming translation elongation stalled by miscoding errors. PMID:28973849

Factors influencing return to work after hip and knee replacement.

PubMed

Malviya, A; Wilson, G; Kleim, B; Kurtz, S M; Deehan, D

2014-09-01

Return to employment is one of the key goals of joint replacement surgery in the working-age population. There is limited quantitative and qualitative research focusing on return to work after hip and knee replacement. It remains unclear why certain groups of patients are not able to achieve sufficient functional improvement to allow productive return to work while others can. Very little is known about the individual patient and employer perspectives in this regard. To review current evidence for the factors influencing employment outcomes in patients undergoing hip and knee replacement. Original articles and reviews in Medline, Embase and PsycINFO from 1987 to 2013 were included in the analysis. Age, patient motivation, employment before surgery and type of job were found to be important factors in determining return to work following hip and knee replacement. There is a need for further qualitative work on how and why these factors influence employment outcomes. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The regulatory mechanism of fruit ripening revealed by analyses of direct targets of the tomato MADS-box transcription factor RIPENING INHIBITOR

PubMed Central

Fujisawa, Masaki; Ito, Yasuhiro

2013-01-01

The developmental process of ripening is unique to fleshy fruits and a key factor in fruit quality. The tomato (Solanum lycopersicum) MADS-box transcription factor RIPENING INHIBITOR (RIN), one of the earliest-acting ripening regulators, is required for broad aspects of ripening, including ethylene-dependent and -independent pathways. However, our knowledge of direct RIN target genes has been limited, considering the broad effects of RIN on ripening. In a recent work published in The Plant Cell, we identified 241 direct RIN target genes by chromatin immunoprecipitation coupled with DNA microarray (ChIP-chip) and transcriptome analysis. Functional classification of the targets revealed that RIN participates in the regulation of many biological processes including well-known ripening processes such as climacteric ethylene production and lycopene accumulation. In addition, we found that ethylene is required for the full expression of RIN and several RIN-targeting transcription factor genes at the ripening stage. Here, based on our recently published findings and additional data, we discuss the ripening processes regulated by RIN and the interplay between RIN and ethylene. PMID:23518588

Can Childhood Factors Predict Workplace Deviance?

PubMed Central

Piquero, Nicole Leeper; Moffitt, Terrie E.

2013-01-01

Compared to the more common focus on street crime, empirical research on workplace deviance has been hampered by highly select samples, cross-sectional research designs, and limited inclusion of relevant predictor variables that bear on important theoretical debates. A key debate concerns the extent to which childhood conduct-problem trajectories influence crime over the life-course, including adults’ workplace crime, whether childhood low self-control is a more important determinant than trajectories, and/or whether each or both of these childhood factors relate to later criminal activity. This paper provides evidence on this debate by examining two types of workplace deviance: production and property deviance separately for males and females. We use data from the Dunedin Multidisciplinary Health and Development Study, a birth cohort followed into adulthood, to examine how childhood factors (conduct-problem trajectories and low self-control) and then adult job characteristics predict workplace deviance at age 32. Analyses revealed that none of the childhood factors matter for predicting female deviance in the workplace but that conduct-problem trajectories did account for male workplace deviance. PMID:24882937

Ultrasensitive direct impedimetric immunosensor for detection of serum HER2.

PubMed

Sharma, Shikha; Zapatero-Rodríguez, Julia; Saxena, Rahul; O'Kennedy, Richard; Srivastava, Sudha

2018-05-30

Assesment of human epidermal growth factor receptor 2 status is a key factor prompting definitive treatment decisions that help in reducing mortality rates associated with breast cancer. In this article, highly sensitive and low-cost impedimetric immunosensor using single-chain fragment variable antibody fragments was developed for quantitative detection of human epidermal growth factor receptor 2 from serum employing gold nanoparticle-modified disposable screen-printed carbon electrodes. The gold nanoparticles facilitate fast electron transfer and offer a biocompatible surface for immobilization of small antibody fragments in an oriented manner, resulting in improved antigen binding efficiency. The single-chain fragment variable antibody fragment-modified screen printed immunosensor exhibits wide dynamic range of 0.01-100 ng mL -1 and detection limit of 0.01 ng mL -1 . The advantages offered by this platform in terms of high sensitivity, broad dynamic range and low-cost demonstrates great potential for improved monitoring of human epidermal growth factor receptor 2 levels for the management of breast and other cancers. Copyright © 2018 Elsevier B.V. All rights reserved.

Disadvantaged persons' participation in health promotion projects: some structural dimensions.

PubMed

Boyce, W F

2001-05-01

A structural perspective was used in studying community participation of disadvantaged groups (poor women, street youth, and disabled persons) in health promotion projects. Five community projects in the Canadian Health Promotion Contribution Program were examined in a comparative case study utilizing in-depth interviews, documents, and secondary sources. Analysis revealed relatively low numbers and restricted range of participants, difficulties in recruiting and maintaining participants, declining rates of active participation over time, and limited target group influence and power. This paper reports on the relationship between various dimensions of structure (social-cultural, organizational, political-legal-economic) and the community participation process. Participation was influenced by structural factors such as bureaucratic rules and regulators, perceived minority group rights and relations, agency reputations and responsibilities, available resources, and organizational roles. Control of projects by target group members, rather than by service agencies, was an important overall organizational structural factor which allowed community members to achieve influence in projects. The study concludes that a conceptual model based on structural factors is useful in explaining how key factors from federal and local levels can restrict or facilitate the community participation process.

Identification of controlling factors for the initiation of corrosion of fresh concrete sewers.

PubMed

Jiang, Guangming; Sun, Xiaoyan; Keller, Jurg; Bond, Philip L

2015-09-01

The development of concrete corrosion in new sewer pipes undergoes an initiation process before reaching an active corrosion stage. This initiation period is assumed to last several months to years but the key factors affecting the process, and its duration, are not well understood. This study is therefore focused on this initial stage of the corrosion process and the effect of key environmental factors. Such knowledge is important for the effective management of corrosion in new sewers, as every year of life extension of such systems has a very high financial benefit. This long-term (4.5 year) study has been conducted in purpose-built corrosion chambers that closely simulated the sewer environment, but with control of three key environmental factors being hydrogen sulfide (H2S) gas phase concentration, relative humidity and air temperature. Fresh concrete coupons, cut from an industry-standard sewer pipe, were exposed to the corrosive conditions in the chambers, both in the gas phase and partially submerged in wastewater. A total of 36 exposure conditions were investigated to determine the controlling factors by regular retrieval of concrete coupons for detailed analysis of surface pH, sulfur compounds (elemental sulfur and sulfate) and concrete mass loss. Corrosion initiation times were thus determined for different exposure conditions. It was found that the corrosion initiation time of both gas-phase and partially-submerged coupons was positively correlated with the gas phase H2S concentration, but only at levels of 10 ppm or below, indicating that sulfide oxidation rate rather than the H2S concentration was the limiting factor during the initiation stage. Relative humidity also played a role for the corrosion initiation of the gas-phase coupons. However, the partially-submerged coupons were not affected by humidity as these coupons were in direct contact with the sewage and hence did have sufficient moisture to enable the microbial processes to proceed. The corrosion initiation time was also shortened by higher gas temperature due to its positive impact on reaction kinetics. These findings provide real opportunities for pro-active sewer asset management with the aim to delay the on-set of the corrosion processes, and hence extend the service life of sewers, through improved prediction and optimization capacity. Copyright © 2015 Elsevier Ltd. All rights reserved.

"You can save time if…"—A qualitative study on internal factors slowing down clinical trials in Sub-Saharan Africa

PubMed Central

Pfeiffer, Constanze; Limacher, Manuela; Burri, Christian

2017-01-01

Background The costs, complexity, legal requirements and number of amendments associated with clinical trials are rising constantly, which negatively affects the efficient conduct of trials. In Sub-Saharan Africa, this situation is exacerbated by capacity and funding limitations, which further increase the workload of clinical trialists. At the same time, trials are critically important for improving public health in these settings. The aim of this study was to identify the internal factors that slow down clinical trials in Sub-Saharan Africa. Here, factors are limited to those that exclusively relate to clinical trial teams and sponsors. These factors may be influenced independently of external conditions and may significantly increase trial efficiency if addressed by the respective teams. Methods We conducted sixty key informant interviews with clinical trial staff working in different positions in two clinical research centres in Kenya, Ghana, Burkina Faso and Senegal. The study covered English- and French-speaking, and Eastern and Western parts of Sub-Saharan Africa. We performed thematic analysis of the interview transcripts. Results We found various internal factors associated with slowing down clinical trials; these were summarised into two broad themes, “planning” and “site organisation”. These themes were consistently mentioned across positions and countries. “Planning” factors related to budget feasibility, clear project ideas, realistic deadlines, understanding of trial processes, adaptation to the local context and involvement of site staff in planning. “Site organisation” factors covered staff turnover, employment conditions, career paths, workload, delegation and management. Conclusions We found that internal factors slowing down clinical trials are of high importance to trial staff. Our data suggest that adequate and coherent planning, careful assessment of the setting, clear task allocation and management capacity strengthening may help to overcome the identified internal factors and allow clinical trials to proceed more efficiently. PMID:28301530

Teachers' Professional Development: What Are the Key Change Factors for Mathematics Teachers?

ERIC Educational Resources Information Center

Pehkonen, Erkki; Torner, Gunter

1999-01-01

Surveyed and interviewed 13 experienced German middle school mathematics teachers to examine key factors causing discontinuity in their professional development. Results included 49 statements about change that fell into four categories. Researchers extracted three change factors not reported in earlier literature: experiences and observations…

Application of a framework for extrapolating chemical effects ...

EPA Pesticide Factsheets

Cross-species extrapolation of toxicity data from limited surrogate test organisms to all wildlife with potential of chemical exposure remains a key challenge in ecological risk assessment. A number of factors affect extrapolation, including the chemical exposure, pharmacokinetics, life-stage, and pathway similarities/differences. Here we propose a framework using a tiered approach for species extrapolation that enables a transparent weight-of-evidence driven evaluation of pathway conservation (or lack thereof) in the context of adverse outcome pathways. Adverse outcome pathways describe the linkages from a molecular initiating event, defined as the chemical-biomolecule interaction, through subsequent key events leading to an adverse outcome of regulatory concern (e.g., mortality, reproductive dysfunction). Tier 1 of the extrapolation framework employs in silico evaluations of sequence and structural conservation of molecules (e.g., receptors, enzymes) associated with molecular initiating events or upstream key events. Such evaluations make use of available empirical and sequence data to assess taxonomic relevance. Tier 2 uses in vitro bioassays, such as enzyme inhibition/activation, competitive receptor binding, and transcriptional activation assays to explore functional conservation of pathways across taxa. Finally, Tier 3 provides a comparative analysis of in vivo responses between species utilizing well-established model organisms to assess departure from

New Roles for Medical Assistants in Innovative Primary Care Practices.

PubMed

Chapman, Susan A; Blash, Lisel K

2017-02-01

To identify and describe new roles for medical assistants (MAs) in innovative care models that improve care while providing training and career advancement opportunities for MAs. Primary data collected at 15 case study sites; 173 key informant interviews and de-identified secondary data on staffing, wages, patient satisfaction, and health outcomes. Researchers used snowball sampling and screening calls to identify 15 organizations using MAs in new roles. Conducted site visits from 2010 to 2012 and updated information in 2014. Thematic analysis explored key topics: factors driving MA role innovation, role description, training required, and wage gains. Categorized outcome data in patient and staff satisfaction, quality of care, and efficiency. New MA roles included health coach, medical scribe, dual role translator, health navigator, panel manager, cross-trained flexible role, and supervisor. Implementation of new roles required extensive training. MA incentives and enhanced compensation varied by role type. New MA roles are part of a larger attempt to reform workflow and relieve primary care providers. Despite some evidence of success, spread has been limited. Key challenges to adoption included leadership and provider resistance to change, cost of additional MA training, and lack of reimbursement for nonbillable services. © Health Research and Educational Trust.

Tree mortality following prescribed fire and a storm surge event in Slash Pine (pinus elliottii var. densa) forests in the Florida Keys, USA

USGS Publications Warehouse

Sah, Jay P.; Ross, Michael S.; Snyder, James R.; Ogurcak, Danielle E.

2010-01-01

In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated with tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.

Overcoming substrate limitations for improved production of ethylene in E. coli.

PubMed

Lynch, Sean; Eckert, Carrie; Yu, Jianping; Gill, Ryan; Maness, Pin-Ching

2016-01-01

Ethylene is an important industrial compound for the production of a wide variety of plastics and chemicals. At present, ethylene production involves steam cracking of a fossil-based feedstock, representing the highest CO2-emitting process in the chemical industry. Biological ethylene production can be achieved via expression of a single protein, the ethylene-forming enzyme (EFE), found in some bacteria and fungi; it has the potential to provide a sustainable alternative to steam cracking, provided that significant increases in productivity can be achieved. A key barrier is determining factors that influence the availability of substrates for the EFE reaction in potential microbial hosts. In the presence of O2, EFE catalyzes ethylene formation from the substrates α-ketoglutarate (AKG) and arginine. The concentrations of AKG, a key TCA cycle intermediate, and arginine are tightly controlled by an intricate regulatory system that coordinates carbon and nitrogen metabolism. Therefore, reliably predicting which genetic changes will ultimately lead to increased AKG and arginine availability is challenging. We systematically explored the effects of media composition (rich versus defined), gene copy number, and the addition of exogenous substrates and other metabolites on the formation of ethylene in Escherichia coli expressing EFE. Guided by these results, we tested a number of genetic modifications predicted to improve substrate supply and ethylene production, including knockout of competing pathways and overexpression of key enzymes. Several such modifications led to higher AKG levels and higher ethylene productivity, with the best performing strain more than doubling ethylene productivity (from 81 ± 3 to 188 ± 13 nmol/OD600/mL). Both EFE activity and substrate supply can be limiting factors in ethylene production. Targeted modifications in central carbon metabolism, such as overexpression of isocitrate dehydrogenase, and deletion of glutamate synthase or the transcription regulator ArgR, can effectively enhance substrate supply and ethylene productivity. These results not only provide insight into the intricate regulatory network of the TCA cycle, but also guide future pathway and genome-scale engineering efforts to further boost ethylene productivity.

Perspectives of San Juan healthcare practitioners on the detection deficit in oral premalignant and early cancers in Puerto Rico: a qualitative research study

PubMed Central

2011-01-01

Background In Puerto Rico, relative to the United States, a disparity exists in detecting oral precancers and early cancers. To identify factors leading to the deficit in early detection, we obtained the perspectives of San Juan healthcare practitioners whose practice could be involved in the detection of such oral lesions. Methods Key informant (KI) interviews were conducted with ten clinicians practicing in or around San Juan, Puerto Rico. We then triangulated our KI interview findings with other data sources, including recent literature on oral cancer detection from various geographic areas, current curricula at the University of Puerto Rico Schools of Medicine and Dental Medicine, as well as local health insurance regulations. Results Key informant-identified factors that likely contribute to the detection deficit include: many practitioners are deficient in knowledge regarding oral cancer and precancer; oral cancer screening examinations are limited regarding which patients receive them and the elements included. In Puerto Rico, specialists generally perform oral biopsies, and patient referral can be delayed by various factors, including government-subsidized health insurance, often referred to as Reforma. Reforma-based issues include often inadequate clinician knowledge regarding Reforma requirements/provisions, diagnostic delays related to Reforma bureaucracy, and among primary physicians, a perceived financial disincentive in referring Reforma patients. Conclusions Addressing these issues may be useful in reducing the deficit in detecting oral precancers and early oral cancer in Puerto Rico. PMID:21612663

[Causes of underreporting of occupational injuries and adverse events in Chile].

PubMed

Luengo, Carolina; Paravic, Tatiana; Valenzuela, Sandra

2016-02-01

Objective To describe the causes of underreporting of occupational injuries and adverse events as identified in the international literature and by key informants in the area of health and risk prevention in Chile. Methods The study uses a qualitative descriptive approach. This includes a systematized literature review that follows the SALSA method (Search, Appraisal, Synthesis and Analysis) and is in line with the PRISMA statement (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). In addition, interviews were conducted with informants in the area of health and risk prevention in Chile. Results The leading causes of underreporting of occupational injuries as described in the literature and by key informants were economic factors and ignorance. With regard to adverse events, the principal causes indicated were fear of sanctions, limited support provided by the authorities, lack of knowledge, and excessive workload. Conclusions It is important to continue working to strengthen the reporting of occupational injuries and adverse events and to implement measures aimed at minimizing factors that appear to be the leading causes of underreporting. In the case of occupational injuries, this means making sure that economic factors are not an impediment but rather an incentive to reporting. With respect to adverse events, steps should be taken to eliminate the fear of sanctions and to develop recommendations, focusing more on systemic improvements than on individuals, to promote joint learning. In both cases it will be necessary to combat ignorance through continuous, systematic training and support.

The bleaching of teeth: a review of the literature.

PubMed

Joiner, Andrew

2006-08-01

To review current knowledge of tooth whitening with respect to external bleaching methods. The scope is the external bleaching of vital teeth and focuses on mechanisms; in vivo and in vitro measurement methods, and factors influencing the efficacy of the whitening process. "Medline" and "ISI Web of Science" databases from 1966 and 1974, respectively were searched electronically with key words tooth, teeth, colo*r, white*, bleach* and peroxide. The importance of tooth whitening for patients and consumers has seen a dramatic increase in the number of products and procedures over recent years, with a concomitant rise in publications on this topic. Literature suggests that the mechanisms of tooth whitening by peroxide occur by the diffusion of peroxide through enamel to cause oxidation and hence lightening of coloured species, particularly within the dentinal regions. A number of approaches are available for measuring changes in tooth colour. These include visual measurements by trained clinicians and instrumental measurements using spectrophotometry, chromameters and digital image analysis. The key factors that affect tooth whitening efficacy by peroxide containing products are concentration and time. In general, higher concentrations are faster than lower concentrations. However, lower concentrations can approach the efficacy of higher concentrations with extended treatment times. Alternative bleach systems to peroxide have received only minor attention. The efficacy of light activated systems versus non-light activated controls in clinical studies is limited and conflicting. Other factors which can influence tooth bleaching outcome include type of stain, initial tooth colour and subject age.

Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

PubMed

Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

2017-05-01

Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

Maximizing the benefits of antiretroviral therapy for key affected populations

PubMed Central

Grubb, Ian R; Beckham, Sarah W; Kazatchkine, Michel; Thomas, Ruth M; Albers, Eliot R; Cabral, Mauro; Lange, Joep; Vella, Stefano; Kurian, Manoj; Beyrer, Chris

2014-01-01

Introduction Scientific research has demonstrated the clinical benefits of earlier initiation of antiretroviral treatment (ART), and that ART can markedly reduce HIV transmission to sexual partners. Ensuring universal access to ART for those who need it has long been a core principle of the HIV response, and extending the benefits of ART to key populations is critical to increasing the impact of ART and the overall effectiveness of the HIV response. However, this can only be achieved through coordinated efforts to address political, social, legal and economic barriers that key populations face in accessing HIV services. Discussion Recent analyses show that HIV prevalence levels among key populations are far higher than among the general population, and they experience a range of biological and behavioural factors, and social, legal and economic barriers that increase their vulnerability to HIV and have resulted in alarmingly low ART coverage. World Health Organization 2014 consolidated guidance on HIV among key populations offers the potential for increased access to ART by key populations, following the same principles as for the general adult population. However, it should not be assumed that key populations will achieve greater access to ART unless stigma, discrimination and punitive laws, policies and practices that limit access to ART and other HIV interventions in many countries are addressed. Conclusions Rights-based approaches and investments in critical enablers, such as supportive legal and policy environments, are essential to enable wider access to ART and other HIV interventions for key populations. The primary objective of ART should always be to treat the person living with HIV; prevention is an important, additional benefit. ART should be provided only with informed consent. The preventive benefits of treatment must not be used as a pretext for failure to provide other necessary HIV programming for key populations, including comprehensive harm reduction and other prevention interventions tailored to meet the needs of key populations. An end to AIDS is only possible if we overcome the barriers of criminalization, stigma and discrimination that remain key drivers of the HIV epidemics among key populations. PMID:25043380

Maximizing the benefits of antiretroviral therapy for key affected populations.

PubMed

Grubb, Ian R; Beckham, Sarah W; Kazatchkine, Michel; Thomas, Ruth M; Albers, Eliot R; Cabral, Mauro; Lange, Joep; Vella, Stefano; Kurian, Manoj; Beyrer, Chris

2014-01-01

Scientific research has demonstrated the clinical benefits of earlier initiation of antiretroviral treatment (ART), and that ART can markedly reduce HIV transmission to sexual partners. Ensuring universal access to ART for those who need it has long been a core principle of the HIV response, and extending the benefits of ART to key populations is critical to increasing the impact of ART and the overall effectiveness of the HIV response. However, this can only be achieved through coordinated efforts to address political, social, legal and economic barriers that key populations face in accessing HIV services. Recent analyses show that HIV prevalence levels among key populations are far higher than among the general population, and they experience a range of biological and behavioural factors, and social, legal and economic barriers that increase their vulnerability to HIV and have resulted in alarmingly low ART coverage. World Health Organization 2014 consolidated guidance on HIV among key populations offers the potential for increased access to ART by key populations, following the same principles as for the general adult population. However, it should not be assumed that key populations will achieve greater access to ART unless stigma, discrimination and punitive laws, policies and practices that limit access to ART and other HIV interventions in many countries are addressed. Rights-based approaches and investments in critical enablers, such as supportive legal and policy environments, are essential to enable wider access to ART and other HIV interventions for key populations. The primary objective of ART should always be to treat the person living with HIV; prevention is an important, additional benefit. ART should be provided only with informed consent. The preventive benefits of treatment must not be used as a pretext for failure to provide other necessary HIV programming for key populations, including comprehensive harm reduction and other prevention interventions tailored to meet the needs of key populations. An end to AIDS is only possible if we overcome the barriers of criminalization, stigma and discrimination that remain key drivers of the HIV epidemics among key populations.

14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.

Code of Federal Regulations, 2010 CFR

2010-01-01

...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...

14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.

Code of Federal Regulations, 2013 CFR

2013-01-01

...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...

14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.

Code of Federal Regulations, 2012 CFR

2012-01-01

...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...

14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.

Code of Federal Regulations, 2011 CFR

2011-01-01

...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...

14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.

Code of Federal Regulations, 2014 CFR

2014-01-01

...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...

A systems biology approach identifies molecular networks defining skeletal muscle abnormalities in chronic obstructive pulmonary disease.

PubMed

Turan, Nil; Kalko, Susana; Stincone, Anna; Clarke, Kim; Sabah, Ayesha; Howlett, Katherine; Curnow, S John; Rodriguez, Diego A; Cascante, Marta; O'Neill, Laura; Egginton, Stuart; Roca, Josep; Falciani, Francesco

2011-09-01

Chronic Obstructive Pulmonary Disease (COPD) is an inflammatory process of the lung inducing persistent airflow limitation. Extensive systemic effects, such as skeletal muscle dysfunction, often characterize these patients and severely limit life expectancy. Despite considerable research efforts, the molecular basis of muscle degeneration in COPD is still a matter of intense debate. In this study, we have applied a network biology approach to model the relationship between muscle molecular and physiological response to training and systemic inflammatory mediators. Our model shows that failure to co-ordinately activate expression of several tissue remodelling and bioenergetics pathways is a specific landmark of COPD diseased muscles. Our findings also suggest that this phenomenon may be linked to an abnormal expression of a number of histone modifiers, which we discovered correlate with oxygen utilization. These observations raised the interesting possibility that cell hypoxia may be a key factor driving skeletal muscle degeneration in COPD patients.

Parametric amplification in MoS2 drum resonator.

PubMed

Prasad, Parmeshwar; Arora, Nishta; Naik, A K

2017-11-30

Parametric amplification is widely used in diverse areas from optics to electronic circuits to enhance low level signals by varying relevant system parameters. Parametric amplification has also been performed in several micro-nano resonators including nano-electromechanical system (NEMS) resonators based on a two-dimensional (2D) material. Here, we report the enhancement of mechanical response in a MoS 2 drum resonator using degenerate parametric amplification. We use parametric pumping to modulate the spring constant of the MoS 2 resonator and achieve a 10 dB amplitude gain. We also demonstrate quality factor enhancement in the resonator with parametric amplification. We investigate the effect of cubic nonlinearity on parametric amplification and show that it limits the gain of the mechanical resonator. Amplifying ultra-small displacements at room temperature and understanding the limitations of the amplification in these devices is key for using these devices for practical applications.

DREAM-3D and the importance of model inputs and boundary conditions

NASA Astrophysics Data System (ADS)

Friedel, Reiner; Tu, Weichao; Cunningham, Gregory; Jorgensen, Anders; Chen, Yue

2015-04-01

Recent work on radiation belt 3D diffusion codes such as the Los Alamos "DREAM-3D" code have demonstrated the ability of such codes to reproduce realistic magnetospheric storm events in the relativistic electron dynamics - as long as sufficient "event-oriented" boundary conditions and code inputs such as wave powers, low energy boundary conditions, background plasma densities, and last closed drift shell (outer boundary) are available. In this talk we will argue that the main limiting factor in our modeling ability is no longer our inability to represent key physical processes that govern the dynamics of the radiation belts (radial, pitch angle and energy diffusion) but rather our limitations in specifying accurate boundary conditions and code inputs. We use here DREAM-3D runs to show the sensitivity of the modeled outcomes to these boundary conditions and inputs, and also discuss alternate "proxy" approaches to obtain the required inputs from other (ground-based) sources.

Healing Africa? Reflections on the peace-building role of a health-based non governmental organization operating in eastern Democratic Republic of Congo.

PubMed

D'Errico, Nicole C; Wake, Christopher M; Wake, Rachel M

2010-01-01

Whilst there are convincing theoretical arguments about the peace-building potential of the health sector, case studies documenting its interventions remain limited. This article contributes to the existing 'Peace through Health' literature by considering the model of HEAL Africa, a health-based non-governmental organization operating in Eastern Congo. Several of HEAL Africa's projects seek to prevent and reduce key risk factors; for conflict, and to contribute to longer term rehabilitation. Many of these interventions are born out of HEAL's emphasis on providing emergency health care--and the neutrality, legitimacy, access and longevity which this generates. However, this focus also tends to act as a limiting factor on the application and resourcing of its conflict prevention and reconstruction efforts. Whilst this case study warns against overstating the potential role of the health sector in promoting peace, HEAL's activities provide evidence of the types of positive contributions that can be made in practice. The role of the health sector, equipped as it is with useful tools for conflict transformation, should therefore be considered more proactively by the peace-building community.

An 8-PSK TDMA uplink modulation and coding system

NASA Technical Reports Server (NTRS)

Ames, S. A.

1992-01-01

The combination of 8-phase shift keying (8PSK) modulation and greater than 2 bits/sec/Hz drove the design of the Nyquist filter to one specified to have a rolloff factor of 0.2. This filter when built and tested was found to produce too much intersymbol interference and was abandoned for a design with a rolloff factor of 0.4. The preamble is limited to 100 bit periods of the uncoded bit period of 5 ns for a maximum preamble length of 500 ns or 40 8PSK symbol times at 12.5 ns per symbol. For 8PSK modulation, the required maximum degradation of 1 dB in -20 dB cochannel interference (CCI) drove the requirement for forward error correction coding. In this contract, the funding was not sufficient to develop the proposed codec so the codec was limited to a paper design during the preliminary design phase. The mechanization of the demodulator is digital, starting from the output of the analog to digital converters which quantize the outputs of the quadrature phase detectors. This approach is amenable to an application specific integrated circuit (ASIC) replacement in the next phase of development.

Dissection of Host Susceptibility to Bacterial Infections and Its Toxins.

PubMed

Nashef, Aysar; Agbaria, Mahmoud; Shusterman, Ariel; Lorè, Nicola Ivan; Bragonzi, Alessandra; Wiess, Ervin; Houri-Haddad, Yael; Iraqi, Fuad A

2017-01-01

Infection is one of the leading causes of human mortality and morbidity. Exposure to microbial agents is obviously required. However, also non-microbial environmental and host factors play a key role in the onset, development and outcome of infectious disease, resulting in large of clinical variability between individuals in a population infected with the same microbe. Controlled and standardized investigations of the genetics of susceptibility to infectious disease are almost impossible to perform in humans whereas mouse models allow application of powerful genomic techniques to identify and validate causative genes underlying human diseases with complex etiologies. Most of current animal models used in complex traits diseases genetic mapping have limited genetic diversity. This limitation impedes the ability to create incorporated network using genetic interactions, epigenetics, environmental factors, microbiota, and other phenotypes. A novel mouse genetic reference population for high-resolution mapping and subsequently identifying genes underlying the QTL, namely the Collaborative Cross (CC) mouse genetic reference population (GRP) was recently developed. In this chapter, we discuss a variety of approaches using CC mice for mapping genes underlying quantitative trait loci (QTL) to dissect the host response to polygenic traits, including infectious disease caused by bacterial agents and its toxins.

Wideband optical sensing using pulse interferometry.

PubMed

Rosenthal, Amir; Razansky, Daniel; Ntziachristos, Vasilis

2012-08-13

Advances in fabrication of high-finesse optical resonators hold promise for the development of miniaturized, ultra-sensitive, wide-band optical sensors, based on resonance-shift detection. Many potential applications are foreseen for such sensors, among them highly sensitive detection in ultrasound and optoacoustic imaging. Traditionally, sensor interrogation is performed by tuning a narrow linewidth laser to the resonance wavelength. Despite the ubiquity of this method, its use has been mostly limited to lab conditions due to its vulnerability to environmental factors and the difficulty of multiplexing - a key factor in imaging applications. In this paper, we develop a new optical-resonator interrogation scheme based on wideband pulse interferometry, potentially capable of achieving high stability against environmental conditions without compromising sensitivity. Additionally, the method can enable multiplexing several sensors. The unique properties of the pulse-interferometry interrogation approach are studied theoretically and experimentally. Methods for noise reduction in the proposed scheme are presented and experimentally demonstrated, while the overall performance is validated for broadband optical detection of ultrasonic fields. The achieved sensitivity is equivalent to the theoretical limit of a 6 MHz narrow-line width laser, which is 40 times higher than what can be usually achieved by incoherent interferometry for the same optical resonator.

Demonstration of emulator-based Bayesian calibration of safety analysis codes: Theory and formulation

DOE PAGES

Yurko, Joseph P.; Buongiorno, Jacopo; Youngblood, Robert

2015-05-28

System codes for simulation of safety performance of nuclear plants may contain parameters whose values are not known very accurately. New information from tests or operating experience is incorporated into safety codes by a process known as calibration, which reduces uncertainty in the output of the code and thereby improves its support for decision-making. The work reported here implements several improvements on classic calibration techniques afforded by modern analysis techniques. The key innovation has come from development of code surrogate model (or code emulator) construction and prediction algorithms. Use of a fast emulator makes the calibration processes used here withmore » Markov Chain Monte Carlo (MCMC) sampling feasible. This study uses Gaussian Process (GP) based emulators, which have been used previously to emulate computer codes in the nuclear field. The present work describes the formulation of an emulator that incorporates GPs into a factor analysis-type or pattern recognition-type model. This “function factorization” Gaussian Process (FFGP) model allows overcoming limitations present in standard GP emulators, thereby improving both accuracy and speed of the emulator-based calibration process. Calibration of a friction-factor example using a Method of Manufactured Solution is performed to illustrate key properties of the FFGP based process.« less

Determinants of evidence use in public health policy making: Results from a study across six EU countries.

PubMed

van de Goor, Ien; Hämäläinen, Riitta-Maija; Syed, Ahmed; Juel Lau, Cathrine; Sandu, Petru; Spitters, Hilde; Eklund Karlsson, Leena; Dulf, Diana; Valente, Adriana; Castellani, Tommaso; Aro, Arja R

2017-03-01

The knowledge-practice gap in public health is widely known. The importance of using different types of evidence for the development of effective health promotion has also been emphasized. Nevertheless, in practice, intervention decisions are often based on perceived short-term opportunities, lacking the most effective approaches, thus limiting the impact of health promotion strategies. This article focuses on facilitators and barriers in the use of evidence in developing health enhancing physical activity policies. Data was collected in 2012 by interviewing 86 key stakeholders from six EU countries (FI, DK, UK, NL, IT, RO) using a common topic guide. Content analysis and concept mapping was used to construct a map of facilitators and barriers. Barriers and facilitators experienced by most stakeholders and policy context in each country are analysed. A lack of locally useful and concrete evidence, evidence on costs, and a lack of joint understanding were specific hindrances. Also users' characteristics and the role media play were identified as factors of influence. Attention for individual and social factors within the policy context might provide the key to enhance more sustainable evidence use. Developing and evaluating tailored approaches impacting on networking, personal relationships, collaboration and evidence coproduction is recommended. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Characterization of Factors Affecting Nanoparticle Tracking Analysis Results With Synthetic and Protein Nanoparticles.

PubMed

Krueger, Aaron B; Carnell, Pauline; Carpenter, John F

2016-04-01

In many manufacturing and research areas, the ability to accurately monitor and characterize nanoparticles is becoming increasingly important. Nanoparticle tracking analysis is rapidly becoming a standard method for this characterization, yet several key factors in data acquisition and analysis may affect results. Nanoparticle tracking analysis is prone to user input and bias on account of a high number of parameters available, contains a limited analysis volume, and individual sample characteristics such as polydispersity or complex protein solutions may affect analysis results. This study systematically addressed these key issues. The integrated syringe pump was used to increase the sample volume analyzed. It was observed that measurements recorded under flow caused a reduction in total particle counts for both polystyrene and protein particles compared to those collected under static conditions. In addition, data for polydisperse samples tended to lose peak resolution at higher flow rates, masking distinct particle populations. Furthermore, in a bimodal particle population, a bias was seen toward the larger species within the sample. The impacts of filtration on an agitated intravenous immunoglobulin sample and operating parameters including "MINexps" and "blur" were investigated to optimize the method. Taken together, this study provides recommendations on instrument settings and sample preparations to properly characterize complex samples. Copyright © 2016. Published by Elsevier Inc.

Advancing Implementation of Evidence-Based Public Health in China: An Assessment of the Current Situation and Suggestions for Developing Regions.

PubMed

Shi, Jianwei; Jiang, Chenghua; Tan, Duxun; Yu, Dehua; Lu, Yuan; Sun, Pengfei; Pan, Ying; Zhang, Hanzhi; Wang, Zhaoxin; Yang, Beilei

2016-01-01

Objective. Existing research shows a serious scarcity of EBPH practice in China and other developing regions; as an exploratory study, this study aimed to assess the current EBPH implementation status in Shanghai of China qualitatively. Methods. Using semistructured key informant interviews, we examined the status of and impediments to the lagging EBPH in China. Data were analyzed based on the Consolidated Framework for Implementation Research (CFIR). Results. Chinese public health practitioners knew more about evidence-based medicine but less about EBPH. The situation was worse in community healthcare centers. Participants perceived that evidence sources were limited and the quality of evidence was low. Concerning the inner setting factors, the structural characteristics, networks and communications, implementation climate, and leadership engagement were confronted with many problems. Among the outer setting factors, external government policies and incentives and low patient compliance were the key problems. Additionally, public health practitioners in Shanghai lacked sufficient awareness of EBPH. Furthermore, the current project-based EBPH lacks a systematic implementation system. Conclusions. Existing practical perspectives on EBPH indicate a lag in the advocacy of this new ideology in China. It would be advisable for healthcare institutions to take the initiative to explore feasible and multiple methods of EBPH promotion.

ULK1 regulates melanin levels in MNT-1 cells independently of mTORC1.

PubMed

Kalie, Eyal; Razi, Minoo; Tooze, Sharon A

2013-01-01

Melanosomes are lysosome-related organelles that serve as specialized sites of melanin synthesis and storage in melanocytes. The progression of melanosomes through the different stages of their formation requires trafficking of specific proteins and membrane constituents in a sequential manner, which is likely to deploy ubiquitous cellular machinery along with melanocyte-specific proteins. Recent evidence revealed a connection between melanogenesis and the autophagy machinery, suggesting a novel role for members of the latter in melanocytes. Here we focused on ULK1, a key autophagy protein which is negatively regulated by mTORC1, to assess its potential role in melanogenesis in MNT-1 cells. We found that ULK1 depletion causes an increase in melanin levels, suggesting an inhibitory function for this protein in melanogenesis. Furthermore, this increase was accompanied by increased transcription of MITF (microphthalmia-associated transcription factor) and tyrosinase and by elevated protein levels of tyrosinase, the rate-limiting factor in melanin biogenesis. We also provide evidence to show that ULK1 function in this context is independent of the canonical ULK1 autophagy partners, ATG13 and FIP200. Furthermore we show that regulation of melanogenesis by ULK1 is independent of mTORC1 inhibition. Our data thus provide intriguing insights regarding the involvement of the key regulatory autophagy machinery in melanogenesis.

The information needs of women who have undergone breast reconstruction. Part II: Information giving and content of information.

PubMed

Wolf, Lisa

2004-12-01

Women diagnosed with breast cancer treated by mastectomy can choose breast reconstruction. The information needs of women undergoing this procedure have only been addressed in the research literature to a limited extent. A qualitative approach was used to explore the experiences of women who had undergone breast reconstruction with a specific focus on their views on how they considered their information needs could best be met. A purposeful sample of eight women was recruited to participate in two focus groups, each lasting 2 hours. Framework analysis was used to develop an index of key themes and sub themes which transformed the data into a structured record which facilitated systematic analysis. This paper will present the emergent key themes regarding information giving and the content of information that women perceive as important when preparing for breast reconstruction. Process, delivery and patient factors are presented in the category of information giving. Several sub themes are discussed concerning the content of information considered to be relevant. Those involved in imparting information to women about such surgery should be aware of the type of information that is considered relevant, the manner in which it should be delivered and timing factors that implicate on the process.

Women's Health at Work Program: musculoskeletal pain experienced by women of Chinese background working on market gardens in the Sydney Basin.

PubMed

Innes, Ev; Crowther, Amber; Fonti, Fiona; Quayle, Leonie

2010-01-01

OBJECTIVE/PARTICIPANTS: This report describes a project undertaken by three final (4th) year occupational therapy undergraduate students from the University of Sydney, Australia, in their final fieldwork placement. The project involved women from a Chinese background who worked on market gardens across the Sydney Basin. Its purpose was to identify musculoskeletal risks in the work environment and work practices of a selected group of seven Cantonese-speaking women working on market gardens in the Western Sydney region. The approaches used in the project reflected a risk management approach, and involved background research, initial interviews, task analysis, hazard identification, risk assessment, data analysis, identification of key issues, and developing recommendations, in collaboration with participants and consultation with professionals. The key issues identified as contributing factors to musculoskeletal pain and injuries were: (1) work practices (long work hours, repetitive work); (2) biomechanical factors (repetitive and sustained work postures, poor manual handling practices) and limited training; (3) ergonomics of the equipment used; (4) fatigue. Two priority areas for intervention were identified: (1) pain management, and (2) preventative strategies (improving both the work environment and work practices). Recommendations were made in collaboration with the women, and in consultation with health professionals.

A case-control study of boat-related injuries and fatalities in Washington State.

PubMed

Stempski, Sarah; Schiff, Melissa; Bennett, Elizabeth; Quan, Linda

2014-08-01

To identify risk factors associated with boat-related injuries and deaths. We performed a case-control study using the Washington Boat Accident Investigation Report Database for 2003-2010. Cases were fatally injured boat occupants, and controls were non-fatally injured boat occupants involved in a boating incident. We evaluated the association between victim, boat and incident factors and risk of death using Poisson regression to estimate RRs and 95% CIs. Of 968 injured boaters, 26% died. Fatalities were 2.6 times more likely to not be wearing a personal flotation device (PFD) and 2.2 times more likely to not have any safety features on their boat compared with those who survived. Boating fatalities were more likely to be in a non-motorised boat, to have alcohol involved in the incident, to be in an incident that involved capsizing, sinking, flooding or swamping, and to involve a person leaving the boat voluntarily, being ejected or falling than those who survived. Increasing PFD use, safety features on the boat and alcohol non-use are key strategies and non-motorised boaters are key target populations to prevent boating deaths. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

[Domiciliary rehabilitation: an innovative form of outpatient medical rehabilitation].

PubMed

Schmidt-Ohlemann, M; Schweizer, C

2009-02-01

Domiciliary rehabilitation is an innovative form of outpatient medical rehabilitation. All components of service provision are delivered in the rehabilitant's home by a multidisciplinary team headed by a physician. The key context factors in the rehab process can be taken into account firsthand. The target group of domiciliary rehabilitation consists of multimorbid patients with severe functional limitations and complex assistance needs, whose rehabilitation options would be poor without this outreach service. Here, as suggested by the WHO concept of functional health, the interaction between health condition and environmental factors is kept in view much better than in other forms of rehabilitation. The positive effects and the efficiency of the rehabilitation measures provided can be assessed very well at a high descriptive level. This fact had been a precondition for legal establishment of domiciliary rehabilitation as a regular service. Domiciliary rehabilitation not only complies with key demands in the health and social policy fields, such as priority of outpatient over inpatient treatment or rehabilitation to precede and accompany long term care, it also constitutes an alternative concept challenging the traditional inpatient rehabilitation approach. The patient, hence, no longer is to fit into the institutional framework of outpatient or inpatient rehabilitation, but the team will fit into the specifics of the patient's unique social and material situation.

Consensus on the Definition of Advanced Parkinson's Disease: A Neurologists-Based Delphi Study (CEPA Study).

PubMed

Luquin, Maria-Rosario; Kulisevsky, Jaime; Martinez-Martin, Pablo; Mir, Pablo; Tolosa, Eduardo S

2017-01-01

To date, no consensus exists on the key factors for diagnosing advanced Parkinson disease (APD). To obtain consensus on the definition of APD, we performed a prospective, multicenter, Spanish nationwide, 3-round Delphi study (CEPA study). An ad hoc questionnaire was designed with 33 questions concerning the relevance of several clinical features for APD diagnosis. In the first-round, 240 neurologists of the Spanish Movement Disorders Group participated in the study. The results obtained were incorporated into the questionnaire and both, results and questionnaire, were sent out to and fulfilled by 26 experts in Movement Disorders. Review of results from the second-round led to a classification of symptoms as indicative of "definitive," "probable," and "possible" APD. This classification was confirmed by 149 previous participating neurologists in a third-round, where 92% completely or very much agreed with the classification. Definitive symptoms of APD included disability requiring help for the activities of daily living, presence of motor fluctuations with limitations to perform basic activities of daily living without help, severe dysphagia, recurrent falls, and dementia. These results will help neurologists to identify some key factors in APD diagnosis, thus allowing users to categorize the patients for a homogeneous recognition of this condition.

Facilitating factors and barriers to malaria research utilization for policy development in Malawi.

PubMed

Mwendera, Chikondi A; de Jager, Christiaan; Longwe, Herbert; Phiri, Kamija; Hongoro, Charles; Mutero, Clifford M

2016-10-19

Research on various determinants of health is key in providing evidence for policy development, thereby leading to successful interventions. Utilization of research is an intricate process requiring an understanding of contextual factors. The study was conducted to assess enhancing factors and barriers of research utilization for malaria policy development in Malawi. Qualitative research approach was used through in-depth interviews with 39 key informants that included malaria researchers, policy makers, programme managers, and key stakeholders. Purposive sampling and snowballing techniques were used in identifying key informants. Interview transcripts were entered in QSR Nvivo 11 software for coding and analysis. Respondents identified global efforts as key in advancing knowledge translation, while local political will has been conducive for research utilization. Other factors were availability of research, availability of diverse local researchers and stakeholders supporting knowledge translation. While barriers included: lack of platforms for researcher-public engagement, politics, researchers' lack of communication skills, lack of research collaborations, funder driven research, unknown World Health Organization policy position, and the lack of a malaria research repository. Overall, the study identified facilitating factors to malaria research utilization for policy development in Malawi. These factors need to be systematically coordinated to address the identified barriers and improve on malaria research utilization in policy development. Malaria research can be key in the implementation of evidence-based interventions to reduce the malaria burden and assist in the paradigm shift from malaria control to elimination in Malawi.

Continuous variable quantum cryptography: beating the 3 dB loss limit.

PubMed

Silberhorn, Ch; Ralph, T C; Lütkenhaus, N; Leuchs, G

2002-10-14

We demonstrate that secure quantum key distribution systems based on continuous variable implementations can operate beyond the apparent 3 dB loss limit that is implied by the beam splitting attack. The loss limit was established for standard minimum uncertainty states such as coherent states. We show that, by an appropriate postselection mechanism, we can enter a region where Eve's knowledge on Alice's key falls behind the information shared between Alice and Bob, even in the presence of substantial losses.

Factors That Influence the Practice of Elective Induction of Labor

PubMed Central

Moore, Jennifer; Low, Lisa Kane

2012-01-01

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

Factors that influence the practice of elective induction of labor: what does the evidence tell us?

PubMed

Moore, Jennifer; Low, Lisa Kane

2012-01-01

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

Unpacking capacity to utilize research: A tale of the Burkina Faso public health association.

PubMed

Hamel, Nadia; Schrecker, Ted

2011-01-01

One of the most important challenges in addressing global health is for institutions to monitor and use research in policy-making. In low- and middle-income countries (LMICs), civil society organizations such as health professional associations can be key contributors to effective national health systems. However, there is little empirical data on their capacity to use research. This case study was used to gain insight into the factors that affect the knowledge translation performance of health professional associations in LMICs by describing the organizational elements and processes constituting capacity to use research, and examining the potential determinants of this capacity. Case study methodology was chosen for its flexibility to capture the multiple and often tacit processes within organizational routines. The Burkina Faso Public Health Association (ABSP) was studied, using in-depth, semi-structured interviews and key documents review. Five key dimensions that affect the association's capacity to use research to influence health policy emerged: organizational motivation; catalysts; organizational capacity to acquire and organizational capacity to transform research findings; moderating organizational factors. Also examined were the dissemination strategies used by ABSP and its abilities to enhance its capacity through networking, to advocate for more relevant research and to develop its potential role as knowledge broker, as well as limitations due to scarce resources. We conclude that a better understanding of the organizational capacity to use research of health professional associations in LMICs is needed to assess, improve and reinforce such capacity. Increased knowledge translation potential may leverage research resources and promote knowledge-sharing. Copyright © 2010 Elsevier Ltd. All rights reserved.

Ground-based adaptive optics coronagraphic performance under closed-loop predictive control

NASA Astrophysics Data System (ADS)

Males, Jared R.; Guyon, Olivier

2018-01-01

The discovery of the exoplanet Proxima b highlights the potential for the coming generation of giant segmented mirror telescopes (GSMTs) to characterize terrestrial-potentially habitable-planets orbiting nearby stars with direct imaging. This will require continued development and implementation of optimized adaptive optics systems feeding coronagraphs on the GSMTs. Such development should proceed with an understanding of the fundamental limits imposed by atmospheric turbulence. Here, we seek to address this question with a semianalytic framework for calculating the postcoronagraph contrast in a closed-loop adaptive optics system. We do this starting with the temporal power spectra of the Fourier basis calculated assuming frozen flow turbulence, and then apply closed-loop transfer functions. We include the benefits of a simple predictive controller, which we show could provide over a factor of 1400 gain in raw point spread function contrast at 1 λ/D on bright stars, and more than a factor of 30 gain on an I=7.5 mag star such as Proxima. More sophisticated predictive control can be expected to improve this even further. Assuming a photon-noise limited observing technique such as high-dispersion coronagraphy, these gains in raw contrast will decrease integration times by the same large factors. Predictive control of atmospheric turbulence should therefore be seen as one of the key technologies that will enable ground-based telescopes to characterize terrestrial planets.

Assessing the Evaluative Content of Personality Questionnaires Using Bifactor Models.

PubMed

Biderman, Michael D; McAbee, Samuel T; Job Chen, Zhuo; Hendy, Nhung T

2018-01-01

Exploratory bifactor models with keying factors were applied to item response data for the NEO-FFI-3 and HEXACO-PI-R questionnaires. Loadings on a general factor and positive and negative keying factors correlated with independent estimates of item valence, suggesting that item valence influences responses to these questionnaires. Correlations between personality domain scores and measures of self-esteem, depression, and positive and negative affect were all reduced significantly when the influence of evaluative content represented by the general and keying factors was removed. Findings support the need to model personality inventories in ways that capture reactions to evaluative item content.

Determinants of community structure of zooplankton in heavily polluted river ecosystems

NASA Astrophysics Data System (ADS)

Xiong, Wei; Li, Jie; Chen, Yiyong; Shan, Baoqing; Wang, Weimin; Zhan, Aibin

2016-02-01

River ecosystems are among the most affected habitats globally by human activities, such as the release of chemical pollutants. However, it remains largely unknown how and to what extent many communities such as zooplankton are affected by these environmental stressors in river ecosystems. Here, we aim to determine major factors responsible for shaping community structure of zooplankton in heavily polluted river ecosystems. Specially, we use rotifers in the Haihe River Basin (HRB) in North China as a case study to test the hypothesis that species sorting (i.e. species are “filtered” by environmental factors and occur at environmental suitable sites) plays a key role in determining community structure at the basin level. Based on an analysis of 94 sites across the plain region of HRB, we found evidence that both local and regional factors could affect rotifer community structure. Interestingly, further analyses indicated that local factors played a more important role in determining community structure. Thus, our results support the species sorting hypothesis in highly polluted rivers, suggesting that local environmental constraints, such as environmental pollution caused by human activities, can be stronger than dispersal limitation caused by regional factors to shape local community structure of zooplankton at the basin level.

Pulmonary Delivery of siRNA via Polymeric Vectors as Therapies of Asthma.

PubMed

Xie, Yuran; Merkel, Olivia M

2015-10-01

Asthma is a chronic inflammatory disease. Despite the fact that current therapies, such as the combination of inhaled corticosteroids and β2-agonists, can control the symptoms of asthma in most patients, there is still an urgent need for an alternative anti-inflammatory therapy for patients who suffer from severe asthma but lack acceptable response to conventional therapies. Many molecular factors are involved in the inflammatory process in asthma, and thus blocking the function of these factors could efficiently alleviate airway inflammation. RNA interference (RNAi) is often thought to be the answer in the search for more efficient and biocompatible treatments. However, difficulties of efficient delivery of small interference RNA (siRNA), the key factor in RNAi, to target cells and tissues have limited its clinical application. In this review, we summarize cytokines and chemokines, transcription factors, tyrosine kinases, and costimulatory factors that have been reported as targets of siRNA-mediated treatment in experimental asthma. Additionally, we conclude several targeted delivery systems of siRNA to specific cells such as T cells, macrophages, and dendritic cells, which could potentially be applied in asthma therapy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Minireview: roles of the forkhead transcription factor FOXL2 in granulosa cell biology and pathology.

PubMed

Pisarska, Margareta D; Barlow, Gillian; Kuo, Fang-Ting

2011-04-01

The forkhead transcription factor (FOXL2) is an essential transcription factor in the ovary. It is important in ovarian development and a key factor in female sex determination. In addition, FOXL2 plays a significant role in the postnatal ovary and follicle maintenance. The diverse transcriptional activities of FOXL2 are likely attributable to posttranslational modifications and binding to other key proteins involved in granulosa cell function. Mutations of FOXL2 lead to disorders of ovarian function ranging from premature follicle depletion and ovarian failure to unregulated granulosa cell proliferation leading to tumor formation. Thus, FOXL2 is a key regulator of granulosa cell function and a master transcription factor in these cells.

Minireview: Roles of the Forkhead Transcription Factor FOXL2 in Granulosa Cell Biology and Pathology

PubMed Central

Barlow, Gillian; Kuo, Fang-Ting

2011-01-01

The forkhead transcription factor (FOXL2) is an essential transcription factor in the ovary. It is important in ovarian development and a key factor in female sex determination. In addition, FOXL2 plays a significant role in the postnatal ovary and follicle maintenance. The diverse transcriptional activities of FOXL2 are likely attributable to posttranslational modifications and binding to other key proteins involved in granulosa cell function. Mutations of FOXL2 lead to disorders of ovarian function ranging from premature follicle depletion and ovarian failure to unregulated granulosa cell proliferation leading to tumor formation. Thus, FOXL2 is a key regulator of granulosa cell function and a master transcription factor in these cells. PMID:21248146

The relationship between addiction and religion and its possible implication for care.

PubMed

Borras, Laurence; Khazaal, Yasser; Khan, Riaz; Mohr, Sylvia; Kaufmann, Yves-Alexandre; Zullino, Daniele; Huguelet, Philippe

2010-12-01

Spirituality is a topic of increasing interest to clinicians and researchers interested in addiction because its perceived role in the promotion of meaningfulness in the recovery from addiction. Our review of the literature evaluates different domains relative to the relation between addiction, religion, and psychiatric treatment. Spirituality as a protective or precipitating factor for substance use and as a key component of recovery will be debated. Illustrations of its potential and limitations as a component of treatment will be presented. Types of investigation and integration of this dimension in an eventual therapeutic process strictly respecting the needs and specificities of each one will be discussed.

Cost Analysis of Renewable Energy-Based Microgrids

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

Giraldez Miner, Julieta I; Singh, Shruti; Gao, David Wenzhong

This paper analyzes the cost composition of microgrid construction as well as the influencing key factors. The Microgrid Cost Study aims at identifying the average cost of a typical microgrid project. The project is limited to the vicinity of U.S. and hence takes into account of only existing microgrid projects in U.S. The project's objective is to find cost of microgrid and its individual components for next 5 years. This will help in R&D for future microgrid projects as well as help investors/developers/researchers get an idea about the cost of their projects that they might want to start in nearmore » future.« less

HOX Genes as Potential Markers of Circulating Tumour Cells.

PubMed

Morgan, R; El-Tanani, M

2016-01-01

Circulating tumour cells (CTCs) have significant diagnostic potential as they can reflect both the presence and recurrence of a wide range of cancers. However, this potential continues to be limited by the lack of robust and accessible isolation technologies. An alternative to isolation might be their direct detection amongst other peripheral blood cells, although this would require markers that allow them to be distinguished from an exceptionally high background signal. This review assesses the potential role of HOX genes, a family of homeodomain containing transcription factors with key roles in both embryonic development and oncogenesis, as unique and possibly disease specific markers of CTCs.

[The willingness-to-pay concept in question].

PubMed

Mould Quevedo, Joaquín F; Contreras Hernández, Iris; Garduño Espinosa, Juan; Salinas Escudero, Guillermo

2009-04-01

The adequacy of the concept of willingness to pay within health economics evaluations is reviewed. A considerable number of researchers in the literature have pointed out multiple methodological issues involving willingness-to-pay estimates. On the other hand, the theoretical discussion about the aggregation of individual preferences within an aggregate demand remains open. However, over the last 20 years, willingness-to-pay estimates alongside health economics research significantly increased and in many cases they are one of the key factors for decision making on issues of health policies. The article describes some limitations of this approach as well as the potential distorting effect that it might have on health economics evaluations.

Coping with "absence-presence": noncustodial fathers' parenting behaviors.

PubMed

Baum, Nehami

2004-07-01

This article is based on the view that the nature of the divorced father's involvement with his children is affected by psychological processes that enable him to separate his parental from his spousal role and identity. It argues that the ability to cope with the simultaneous absence of the spousal role and identity and presence of the paternal role and identity is a key factor in shaping the divorced father's behavior toward his children. The article illustrates the claim in 3 case studies showing (a) parental functioning marred by ongoing conflict with the children's mother, (b) disengagement, and (c) stable and consistent parental functioning within the inevitable limitations of noncustodial fatherhood.

Effect of the Key Mixture Parameters on Shrinkage of Reactive Powder Concrete

PubMed Central

Zubair, Ahmed

2014-01-01

Reactive powder concrete (RPC) mixtures are reported to have excellent mechanical and durability characteristics. However, such concrete mixtures having high amount of cementitious materials may have high early shrinkage causing cracking of concrete. In the present work, an attempt has been made to study the simultaneous effects of three key mixture parameters on shrinkage of the RPC mixtures. Considering three different levels of the three key mixture factors, a total of 27 mixtures of RPC were prepared according to 33 factorial experiment design. The specimens belonging to all 27 mixtures were monitored for shrinkage at different ages over a total period of 90 days. The test results were plotted to observe the variation of shrinkage with time and to see the effects of the key mixture factors. The experimental data pertaining to 90-day shrinkage were used to conduct analysis of variance to identify significance of each factor and to obtain an empirical equation correlating the shrinkage of RPC with the three key mixture factors. The rate of development of shrinkage at early ages was higher. The water to binder ratio was found to be the most prominent factor followed by cement content with the least effect of silica fume content. PMID:25050395

Effect of the key mixture parameters on shrinkage of reactive powder concrete.

PubMed

Ahmad, Shamsad; Zubair, Ahmed; Maslehuddin, Mohammed

2014-01-01

Reactive powder concrete (RPC) mixtures are reported to have excellent mechanical and durability characteristics. However, such concrete mixtures having high amount of cementitious materials may have high early shrinkage causing cracking of concrete. In the present work, an attempt has been made to study the simultaneous effects of three key mixture parameters on shrinkage of the RPC mixtures. Considering three different levels of the three key mixture factors, a total of 27 mixtures of RPC were prepared according to 3(3) factorial experiment design. The specimens belonging to all 27 mixtures were monitored for shrinkage at different ages over a total period of 90 days. The test results were plotted to observe the variation of shrinkage with time and to see the effects of the key mixture factors. The experimental data pertaining to 90-day shrinkage were used to conduct analysis of variance to identify significance of each factor and to obtain an empirical equation correlating the shrinkage of RPC with the three key mixture factors. The rate of development of shrinkage at early ages was higher. The water to binder ratio was found to be the most prominent factor followed by cement content with the least effect of silica fume content.

Key Factors in the Success of an Organization's Information Security Culture: A Quantitative Study and Analysis

ERIC Educational Resources Information Center

Pierce, Robert E.

2012-01-01

This research study reviewed relative literature on information security and information security culture within organizations to determine what factors potentially assist an organization in implementing, integrating, and maintaining a successful organizational information security culture. Based on this review of literature, five key factors were…

Consumer-identified barriers and strategies for optimizing technology use in the workplace.

PubMed

De Jonge, Desleigh M; Rodger, Sylvia A

2006-01-01

This article explores the experiences of 26 assistive technology (AT) users having a range of physical impairments as they optimized their use of technology in the workplace. A qualitative research design was employed using in-depth, open-ended interviews and observations of AT users in the workplace. Participants identified many factors that limited their use of technology such as discomfort and pain, limited knowledge of the technology's features, and the complexity of the technology. The amount of time required for training, limited work time available for mastery, cost of training and limitations of the training provided, resulted in an over-reliance on trial and error and informal support networks and a sense of isolation. AT users enhanced their use of technology by addressing the ergonomics of the workstation and customizing the technology to address individual needs and strategies. Other key strategies included tailored training and learning support as well as opportunities to practice using the technology and explore its features away from work demands. This research identified structures important for effective AT use in the workplace which need to be put in place to ensure that AT users are able to master and optimize their use of technology.

Phased Array-Fed Reflector (PAFR) Antenna Architectures for Space-Based Sensors

NASA Technical Reports Server (NTRS)

Cooley, Michael E.

2014-01-01

Communication link and target ranges for satellite communications (SATCOM) and space-based sensors (e.g. radars) vary from approximately 1000 km (for LEO satellites) to 35,800 km (for GEO satellites). At these long ranges, large antenna gains are required and legacy payloads have usually employed large reflectors with single beams that are either fixed or mechanically steered. For many applications, there are inherent limitations that are associated with the use of these legacy antennas/payloads. Hybrid antenna designs using Phased Array Fed Reflectors (PAFRs) provide a compromise between reflectors and Direct Radiating phased Arrays (DRAs). PAFRs provide many of the performance benefits of DRAs while utilizing much smaller, lower cost (feed) arrays. The primary limitation associated with hybrid PAFR architectures is electronic scan range; approximately +/-5 to +/- 10 degrees is typical, but this range depends on many factors. For LEO applications, the earth FOV is approximately +/-55 degrees which is well beyond the range of electronic scanning for PAFRs. However, for some LEO missions, limited scanning is sufficient or the CONOPS and space vehicle designs can be developed to incorporate a combination mechanical slewing and electronic scanning. In this paper, we review, compare and contrast various PAFR architectures with a focus on their general applicability to space missions. We compare the RF performance of various PAFR architectures and describe key hardware design and implementation trades. Space-based PAFR designs are highly multi-disciplinary and we briefly address key hardware engineering design areas. Finally, we briefly describe two PAFR antenna architectures that have been developed at Northrop Grumman.

Disturbance is the key to plant invasions in cold environments.

PubMed

Lembrechts, Jonas J; Pauchard, Aníbal; Lenoir, Jonathan; Nuñez, Martín A; Geron, Charly; Ven, Arne; Bravo-Monasterio, Pablo; Teneb, Ernesto; Nijs, Ivan; Milbau, Ann

2016-12-06

Until now, nonnative plant species were rarely found at high elevations and latitudes. However, partly because of climate warming, biological invasions are now on the rise in these extremely cold environments. These plant invasions make it timely to undertake a thorough experimental assessment of what has previously been holding them back. This knowledge is key to developing efficient management of the increasing risks of cold-climate invasions. Here, we integrate human interventions (i.e., disturbance, nutrient addition, and propagule input) and climatic factors (i.e., temperature) into one seed-addition experiment across two continents: the subantarctic Andes and subarctic Scandinavian mountains (Scandes), to disentangle their roles in limiting or favoring plant invasions. Disturbance was found as the main determinant of plant invader success (i.e., establishment, growth, and flowering) along the entire cold-climate gradient, explaining 40-60% of the total variance in our models, with no indication of any facilitative effect from the native vegetation. Higher nutrient levels additionally stimulated biomass production and flowering. Establishment and flowering displayed a hump-shaped response with increasing elevation, suggesting that competition is the main limit on invader success at low elevations, as opposed to low-growing-season temperatures at high elevations. Our experiment showed, however, that nonnative plants can establish, grow, and flower well above their current elevational limits in high-latitude mountains. We thus argue that cold-climate ecosystems are likely to see rapid increases in plant invasions in the near future as a result of a synergistic interaction between increasing human-mediated disturbances and climate warming.

Materials Safety - Not just Flammability and Toxic Offgassing

NASA Technical Reports Server (NTRS)

Pedley, Michael D.

2007-01-01

For many years, the safety community has focused on a limited subset of materials and processes requirements as key to safety: Materials flammability, Toxic offgassing, Propellant compatibility, Oxygen compatibility, and Stress-corrosion cracking. All these items are important, but the exclusive focus on these items neglects many other items that are equally important to materials safety. Examples include (but are not limited to): 1. Materials process control -- proper qualification and execution of manufacturing processes such as structural adhesive bonding, welding, and forging are crucial to materials safety. Limitation of discussions on materials process control to an arbitrary subset of processes, known as "critical processes" is a mistake, because any process where the quality of the product cannot be verified by inspection can potentially result in unsafe hardware 2 Materials structural design allowables -- development of valid design allowables when none exist in the literature requires extensive testing of multiple lots of materials and is extremely expensive. But, without valid allowables, structural analysis cannot verify structural safety 3. Corrosion control -- All forms of corrosion, not just stress corrosion, can affect structural integrity of hardware 4. Contamination control during ground processing -- contamination control is critical to manufacturing processes such as adhesive bonding and also to elimination foreign objects and debris (FOD) that are hazardous to the crew of manned spacecraft in microgravity environments. 5. Fasteners -- Fastener design, the use of verifiable secondary locking features, and proper verification of fastener torque are essential for proper structural performance This presentation discusses some of these key factors and the importance of considering them in ensuring the safety of space hardware.

Commercializing potassium terbium fluoride, KTF (KTb3F10) faraday crystals for high laser power optical isolator applications

NASA Astrophysics Data System (ADS)

Schlichting, Wolfgang; Stevens, Kevin; Foundos, Greg; Payne, Alexis

2017-10-01

Many scientific lasers and increasingly industrial laser systems operate in <500W and kW output power regime, require high-performance optical isolators to prevent disruptive light feedback into the laser cavity. The optically active Faraday material is the key optical element inside the isolator. SYNOPTICS has been supplying the laser market with Terbium Gallium Garnet (TGG - Tb3Ga5O12) for many years. It is the most commonly used material for the 650-1100nm range and the key advantages for TGG include its cubic crystal structure for alignment free processing, little to no intrinsic birefringence, and ease of manufacture. However, for high-power laser applications TGG is limited by its absorption at 1064nm and its thermo-optic coefficient, dn/dT. Specifically, thermal lensing and depolarization effects become a limiting factor at high laser powers. While TGG absorption has improved significantly over the past few years, there is an intrinsic limit. Now, SYNOPTICS is commercializing the enhanced new crystal Potassium Terbium Fluoride KTF (KTb3F10) that exhibits much smaller nonlinear refractive index and thermo-optic coefficients, and still exhibits a Verdet constant near that of TGG. This cubic crystal has relatively low absorption and thermo-optic coefficients. It is now fully characterized and available for select production orders. At OPTIFAB in October 2017 we present recent results comparing the performance of KTF to TGG in optical isolators and show SYNOPTICS advances in large volume crystal growth and the production ramp up.

Biological insights into the expression of translation initiation factors from recombinant CHOK1SV cell lines and their relationship to enhanced productivity.

PubMed

Mead, Emma J; Masterton, Rosalyn J; Feary, Marc; Obrezanova, Olga; Zhang, Lin; Young, Robert; Smales, C Mark

2015-12-15

Translation initiation is on the critical pathway for the production of monoclonal antibodies (mAbs) by mammalian cells. Formation of a closed loop structure comprised of mRNA, a number of eukaryotic initiation factors (eIFs) and ribosomal proteins has been proposed to aid re-initiation of translation and therefore increase global translational efficiency. We have determined mRNA and protein levels of the key components of the closed loop, eIFs (eIF3a, eIF3b, eIF3c, eIF3h, eIF3i and eIF4G1), poly(A)-binding protein (PABP) 1 and PABP-interacting protein 1 (PAIP1), across a panel of 30 recombinant mAb-producing GS-CHOK1SV cell lines with a broad range of growth characteristics and production levels of a model recombinant mAb. We have used a multi-level statistical approach to investigate the relationship between key performance indicators (cell growth and recombinant antibody productivity) and the intracellular amounts of target translation initiation factor proteins and the mRNAs encoding them. We show that high-producing cell lines maintain amounts of the translation initiation factors involved in the formation of the closed loop mRNA, maintaining these proteins at appropriate levels to deliver enhanced recombinant protein production. We then utilize knowledge of the amounts of these factors to build predictive models for and use cluster analysis to identify, high-producing cell lines. The present study therefore defines the translation initiation factor amounts that are associated with highly productive recombinant GS-CHOK1SV cell lines that may be targets for screening highly productive cell lines or to engineer new host cell lines with the potential for enhanced recombinant antibody productivity. © 2015 Authors; published by Portland Press Limited.

Spanning maternal, newborn and child health (MNCH) and health systems research boundaries: conducive and limiting health systems factors to improving MNCH outcomes in West Africa.

PubMed

Agyepong, Irene Akua; Kwamie, Aku; Frimpong, Edith; Defor, Selina; Ibrahim, Abdallah; Aryeetey, Genevieve C; Lokossou, Virgil; Sombie, Issiaka

2017-07-12

Despite improvements over time, West Africa lags behind global as well as sub-Saharan averages in its maternal, newborn and child health (MNCH) outcomes. This is despite the availability of an increasing body of knowledge on interventions that improve such outcomes. Beyond our knowledge of what interventions work, insights are needed on others factors that facilitate or inhibit MNCH outcome improvement. This study aimed to explore health system factors conducive or limiting to MNCH policy and programme implementation and outcomes in West Africa, and how and why they work in context. We conducted a mixed methods multi-country case study focusing predominantly, but not exclusively, on the six West African countries (Burkina Faso, Benin, Mali, Senegal, Nigeria and Ghana) of the Innovating for Maternal and Child Health in Africa initiative. Data collection involved non-exhaustive review of grey and published literature, and 48 key informant interviews. We validated our findings and conclusions at two separate multi-stakeholder meetings organised by the West African Health Organization. To guide our data collection and analysis, we developed a unique theoretical framework of the link between health systems and MNCH, in which we conceptualised health systems as the foundations, pillars and roofing of a shelter for MNCH, and context as the ground on which the foundation is laid. A multitude of MNCH policies and interventions were being piloted, researched or implemented at scale in the sub-region, most of which faced multiple interacting conducive and limiting health system factors to effective implementation, as well as contextual challenges. Context acted through its effect on health system factors as well as on the social determinants of health. To accelerate and sustain improvements in MNCH outcomes in West Africa, an integrated approach to research and practice of simultaneously addressing health systems and contextual factors alongside MNCH service delivery interventions is needed. This requires multi-level, multi-sectoral and multi-stakeholder engagement approaches that span current geographical, language, research and practice community boundaries in West Africa, and effectively link the efforts of actors interested in health systems strengthening with those of actors interested in MNCH outcome improvement.

Requirements and limits for life in the context of exoplanets

PubMed Central

McKay, Christopher P.

2014-01-01

The requirements for life on Earth, its elemental composition, and its environmental limits provide a way to assess the habitability of exoplanets. Temperature is key both because of its influence on liquid water and because it can be directly estimated from orbital and climate models of exoplanetary systems. Life can grow and reproduce at temperatures as low as −15 °C, and as high as 122 °C. Studies of life in extreme deserts show that on a dry world, even a small amount of rain, fog, snow, and even atmospheric humidity can be adequate for photosynthetic production producing a small but detectable microbial community. Life is able to use light at levels less than 10−5 of the solar flux at Earth. UV or ionizing radiation can be tolerated by many microorganisms at very high levels and is unlikely to be life limiting on an exoplanet. Biologically available nitrogen may limit habitability. Levels of O2 over a few percent on an exoplanet would be consistent with the presence of multicellular organisms and high levels of O2 on Earth-like worlds indicate oxygenic photosynthesis. Other factors such as pH and salinity are likely to vary and not limit life over an entire planet or moon. PMID:24927538

Requirements and limits for life in the context of exoplanets.

PubMed

McKay, Christopher P

2014-09-02

The requirements for life on Earth, its elemental composition, and its environmental limits provide a way to assess the habitability of exoplanets. Temperature is key both because of its influence on liquid water and because it can be directly estimated from orbital and climate models of exoplanetary systems. Life can grow and reproduce at temperatures as low as -15 °C, and as high as 122 °C. Studies of life in extreme deserts show that on a dry world, even a small amount of rain, fog, snow, and even atmospheric humidity can be adequate for photosynthetic production producing a small but detectable microbial community. Life is able to use light at levels less than 10(-5) of the solar flux at Earth. UV or ionizing radiation can be tolerated by many microorganisms at very high levels and is unlikely to be life limiting on an exoplanet. Biologically available nitrogen may limit habitability. Levels of O2 over a few percent on an exoplanet would be consistent with the presence of multicellular organisms and high levels of O2 on Earth-like worlds indicate oxygenic photosynthesis. Other factors such as pH and salinity are likely to vary and not limit life over an entire planet or moon.

Deliberation Makes a Difference: Preparation Strategies for TeamSTEPPS Implementation in Small and Rural Hospitals

PubMed Central

Zhu, Xi; Baloh, Jure; Ward, Marcia M.; Stewart, Greg L.

2016-01-01

Small and rural hospitals face special challenges to implement and sustain organization-wide quality improvement (QI) initiatives due to limited resources and infrastructures. We studied the implementation of TeamSTEPPS, a national QI initiative, in 14 critical access hospitals. Drawing on QI and organization development theories, we propose five strategic preparation steps for TeamSTEPPS: assess needs, reflect on the context, set goals, develop a shared understanding, and select change agents. We explore how hospitals’ practices correspond to suggested best practices by analyzing qualitative data collected through quarterly interviews with key informants. We find that the level of deliberation was a key factor that differentiated hospitals’ practices. Hospitals that were more deliberate in preparing for the five strategic steps were more likely to experience engagement, perceive efficacy, foresee and manage barriers, and achieve progress during implementation. We discuss potential steps that hospitals may take to better prepare for TeamSTEPPS implementation. PMID:26429835

Gliomatosis cerebri: Prognosis based on current molecular markers.

PubMed

Maharaj, Monish M; Phan, Kevin; Xu, Joshua; Fairhall, Jacob; Reddy, Rajesh; Rao, Prashanth J V

2017-09-01

This study aims to review the literature and identify key molecular markers affecting the prognosis of Gliomatosis cerebri (2) to evaluate the level of evidence and identify outstanding markers requiring further study. A literature search was conducted across 5 major databases using the key terms: "Molecular markers" AND "Gliomatosis cerebri" OR "diffuse astrocytoma." Critical appraisal and data presentation was performed inline with the PRISMA guidelines. Following search strategy implementation, 11 studies were included in the final review process. Our data demonstrates significant prognostic value associated with IDH1 132H mutation and variable evidence surrounding the role of INA expression, MGMT promoter methylation and other factors. However, there are significant limitations in the level of evidence obtained. As the genetic basis for the pathogenesis of Gliomatosis cerebri continues to widen, there is little data on markers aside from IDH1 mutation available. IDH1 132H mutation has been demonstrated to have significant effect on survival, particularly in patients with Gliomatosis cerebri type 2. Copyright © 2017 Elsevier Ltd. All rights reserved.

Overcoming substrate limitations for improved production of ethylene in E. coli

DOE PAGES

Lynch, Sean; Eckert, Carrie; Yu, Jianping; ...

2016-01-04

Ethylene is an important industrial compound for the production of a wide variety of plastics and chemicals. At present, ethylene production involves steam cracking of a fossil-based feedstock, representing the highest CO 2-emitting process in the chemical industry. Biological ethylene production can be achieved via expression of a single protein, the ethylene-forming enzyme (EFE), found in some bacteria and fungi; it has the potential to provide a sustainable alternative to steam cracking, provided that significant increases in productivity can be achieved. A key barrier is determining factors that influence the availability of substrates for the EFE reaction in potential microbialmore » hosts. In the presence of O 2, EFE catalyzes ethylene formation from the substrates α-ketoglutarate (AKG) and arginine. The concentrations of AKG, a key TCA cycle intermediate, and arginine are tightly controlled by an intricate regulatory system that coordinates carbon and nitrogen metabolism. Thus, reliably predicting which genetic changes will ultimately lead to increased AKG and arginine availability is challenging.« less

Mapping tissue oxygen in vivo by photoacoustic lifetime imaging

NASA Astrophysics Data System (ADS)

Shao, Qi; Morgounova, Ekaterina; Choi, Jeung-Hwan; Jiang, Chunlan; Bischof, John; Ashkenazi, Shai

2013-03-01

Oxygen plays a key role in the energy metabolism of living organisms. Any imbalance in the oxygen levels will affect the metabolic homeostasis and lead to pathophysiological diseases. Hypoxia, a status of low tissue oxygen, is a key factor in tumor biology as it is highly prominent in tumor tissues. However, clinical tools for assessing tissue oxygenation are limited. The gold standard is polarographic needle electrode which is invasive and not capable of mapping (imaging) the oxygen content in tissue. We applied the method of photoacoustic lifetime imaging (PALI) of oxygen-sensitive dye to small animal tissue hypoxia research. PALI is new technology for direct, non-invasive imaging of oxygen. The technique is based on mapping the oxygen-dependent transient optical absorption of Methylene Blue (MB) by pump-probe photoacoustic imaging. Our studies show the feasibility of imaging of dissolved oxygen distribution in phantoms. In vivo experiments demonstrate that the hypoxia region is consistent with the site of subcutaneously xenografted prostate tumor in mice with adequate spatial resolution and penetration depth.

Compact SPAD-Based Pixel Architectures for Time-Resolved Image Sensors

PubMed Central

Perenzoni, Matteo; Pancheri, Lucio; Stoppa, David

2016-01-01

This paper reviews the state of the art of single-photon avalanche diode (SPAD) image sensors for time-resolved imaging. The focus of the paper is on pixel architectures featuring small pixel size (<25 μm) and high fill factor (>20%) as a key enabling technology for the successful implementation of high spatial resolution SPAD-based image sensors. A summary of the main CMOS SPAD implementations, their characteristics and integration challenges, is provided from the perspective of targeting large pixel arrays, where one of the key drivers is the spatial uniformity. The main analog techniques aimed at time-gated photon counting and photon timestamping suitable for compact and low-power pixels are critically discussed. The main features of these solutions are the adoption of analog counting techniques and time-to-analog conversion, in NMOS-only pixels. Reliable quantum-limited single-photon counting, self-referenced analog-to-digital conversion, time gating down to 0.75 ns and timestamping with 368 ps jitter are achieved. PMID:27223284

[Issues related to secondary osteoporosis associated with growth hormone deficiency in adulthood].

PubMed

Kužma, Martin; Jackuliak, Peter; Killinger, Zdenko; Vaňuga, Peter; Payer, Juraj

Growth hormone (GH) increases linear bone growth through complex hormonal reactions, mainly mediated by insulin like growth factor 1 (IGF1) that is produced mostly by hepatocytes under influence of GH and stimulates differentiation of epiphyseal prechondrocytes. IGF1 and GH play a key role in the linear bone growth after birth and regulation of bone remodelation during the entire lifespan. It is known that adult GH deficient (GHD) patients have decreased BMD and increased risk of low-impact fractures. Most data gathered thus far on the effect of GH replacement on bone status comprise the measurement of quantitative changes of bone mass. Some animal studies with GHD showed that the bone microarchitecture, measured using computed tomography methods, is significantly compromised and improve after GH replacement. However, human studies did not show significantly decreased bone microarchitecture, but limited methodological quality does not allow firm conclusions on this subject.Key words: bone mass - bone quality - fracture - growth hormone - IGF1.

How have health promotion frameworks considered gender?

PubMed

Gelb, Karen; Pederson, Ann; Greaves, Lorraine

2012-12-01

This paper provides an overview of five key internationally recognized health promotion frameworks and assesses their consideration of gender. This analysis was conducted as part of the Promoting Health in Women project, a Canadian initiative focused on generating a framework for effective health promotion for women. To date, no review of health promotion frameworks has specifically focused on assessing the treatment of gender. This analysis draws on a comprehensive literature review that covered available literature on gender and health promotion frameworks published internationally between 1974 and 2010. Analysis of five key health promotion frameworks revealed that although gender was at times mentioned as a determinant of health, gender was never identified and integrated as a factor critical to successful health promotion. This superficial attention to the role of gender in health promotion is problematic as it limits our capacity to understand how gender influences health, health contexts and health promotion, as well as our ability to integrate gender into future comprehensive health promotion strategies.

Using the balanced scorecard to measure Chinese and Japanese hospital performance.

PubMed

Chen, Xiao-yun; Yamauchi, Kazunobu; Kato, Ken; Nishimura, Akio; Ito, Katuski

2006-01-01

The objective of the paper is to confirm the feasibility and value of using the balanced scorecard (BSC) to measure performance in two hospitals in different countries. One hospital from China and another from Japan were chosen and key indicators were selected according to the BSC framework. A comparative hospital performance measurement model was set up using the BSC framework to comprehensively compare hospital performance in two countries. The BSC was found to be effective for underlining existing problems and identifying opportunities for improvements. The BSC also revealed the hospitals' contribution to performance improvement of each country's total health system. Hospital performance comparisons between countries using the BSC depend on the selection of feasible and appropriate key performance indicators, which is occasionally limited by data collection problems. The first use of the BSC to compare hospital performance between China and Japan shows benefits that not only suggests performance improvements in individual hospitals but also reveals effective health factors allowing implementation of valid national health policies.

Occurrence of acrylamide in selected foods and mitigation options.

PubMed

Amrein, Thomas M; Andres, Luca; Escher, Felix; Amadò, Renato

2007-01-01

Acrylamide reduction in certain food products is an important issue for both the food industry and academic research institutions. The present paper summarises past and current research on the occurrence and reduction of acrylamide in potatoes, bakery products, almonds, olives and dried fruit. In potatoes, the control of reducing sugars, process temperature and moisture is imperative to limit acrylamide formation. In bakery products, free asparagine and the type of baking agent largely determine acrylamide formation and present the starting points for reduction. The application of asparaginase is promising in this respect because it acts only on the key precursor, asparagine, whereby the product character remains unchanged. The baking agent NH4HCO3 promotes acrylamide formation in sweet bakery but its replacement by NaHCO3 effectively decreases acrylamide concentrations. Temperature and free asparagine are the key factors for acrylamide formation in roasted almonds. Olives and dried fruit may contain acrylamide and large amounts of acrylamide can be formed upon heating these products, a phenomenon which needs further investigation.

Restricted regions of enhanced growth of Antarctic krill in the circumpolar Southern Ocean.

PubMed

Murphy, Eugene J; Thorpe, Sally E; Tarling, Geraint A; Watkins, Jonathan L; Fielding, Sophie; Underwood, Philip

2017-07-31

Food webs in high-latitude oceans are dominated by relatively few species. Future ocean and sea-ice changes affecting the distribution of such species will impact the structure and functioning of whole ecosystems. Antarctic krill (Euphausia superba) is a key species in Southern Ocean food webs, but there is little understanding of the factors influencing its success throughout much of the ocean. The capacity of a habitat to maintain growth will be crucial and here we use an empirical relationship of growth rate to assess seasonal spatial variability. Over much of the ocean, potential for growth is limited, with three restricted oceanic regions where seasonal conditions permit high growth rates, and only a few areas around the Scotia Sea and Antarctic Peninsula suitable for growth of the largest krill (>60 mm). Our study demonstrates that projections of impacts of future change need to account for spatial and seasonal variability of key ecological processes within ocean ecosystems.

High-throughput automated microfluidic sample preparation for accurate microbial genomics

PubMed Central

Kim, Soohong; De Jonghe, Joachim; Kulesa, Anthony B.; Feldman, David; Vatanen, Tommi; Bhattacharyya, Roby P.; Berdy, Brittany; Gomez, James; Nolan, Jill; Epstein, Slava; Blainey, Paul C.

2017-01-01

Low-cost shotgun DNA sequencing is transforming the microbial sciences. Sequencing instruments are so effective that sample preparation is now the key limiting factor. Here, we introduce a microfluidic sample preparation platform that integrates the key steps in cells to sequence library sample preparation for up to 96 samples and reduces DNA input requirements 100-fold while maintaining or improving data quality. The general-purpose microarchitecture we demonstrate supports workflows with arbitrary numbers of reaction and clean-up or capture steps. By reducing the sample quantity requirements, we enabled low-input (∼10,000 cells) whole-genome shotgun (WGS) sequencing of Mycobacterium tuberculosis and soil micro-colonies with superior results. We also leveraged the enhanced throughput to sequence ∼400 clinical Pseudomonas aeruginosa libraries and demonstrate excellent single-nucleotide polymorphism detection performance that explained phenotypically observed antibiotic resistance. Fully-integrated lab-on-chip sample preparation overcomes technical barriers to enable broader deployment of genomics across many basic research and translational applications. PMID:28128213

Identifying vulnerable Asian Americans under Health Care Reform: working in small businesses and health care coverage.

PubMed

Cook, Won Kim; Tseng, Winston; Ko Chin, Kathy; John, Iyanrick; Chung, Corina

2014-11-01

Working in small businesses has been identified as a key factor for low coverage rates in immigrant communities. In this study, we identify specific cultural and socioeconomic predictors of Asian Americans who work in small businesses to identify subgroups at a greater disadvantage than others in obtaining health insurance. Logistic regression models were fitted using a sample of 3,819 Asian American small business owners and employers extracted from pooled 2005–2012 California Health Interview Survey data. We found that individuals with low income levels, Korean Americans, U.S.-born South Asian and Southeast Asian (other than Vietnamese) Americans, immigrants without citizenship (particularly those lacking a green card), and individuals with limited English proficiency had higher odds of lacking coverage. The odds of being uninsured did not differ between small business owners and employees. Based upon these key findings, we propose several strategies to expand coverage for Asian Americans working in small businesses and their most vulnerable subgroups.

Paradoxical Vocal Cord Motion in Pediatric Patients.

PubMed

Palla, John; Friedman, Aaron D

2016-05-01

Paradoxical vocal cord motion (PVCM), also termed vocal cord dysfunction, is a poorly understood disorder of episodic dyspnea characterized by inappropriate vocal cord adduction during inspiration and potentially during expiration. It can coexist or be confused with asthma, so appropriate diagnosis is key to optimizing treatment success. Although many patients with PVCM may have underlying psychologic issues, there is emerging evidence to suggest that this entity is not psychogenic in every patient. Both laryngeal irritants and exercise have been identified as additional contributing factors in PVCM. Diagnosis of PVCM requires awake laryngoscopic confirmation. However, many patients do not exhibit signs of PVCM during this examination, despite provocation during testing. Therefore, clinical history remains key in determining which patients should proceed with behavioral therapy under the guidance of a speech pathologist. In addition, treatment may include limiting patient exposure to potential sources of laryngeal irritation. Refractory patients may benefit from psychologic assessment and treatment. [Pediatr Ann. 2016;45(5):e184-e188.]. Copyright 2016, SLACK Incorporated.

Key influences in the design and implementation of mental health information systems in Ghana and South Africa.

PubMed

Ahuja, S; Mirzoev, T; Lund, C; Ofori-Atta, A; Skeen, S; Kufuor, A

2016-01-01

Strengthening of mental health information systems (MHIS) is essential to monitor and evaluate mental health services in low and middle-income countries. While research exists assessing wider health management information systems, there is limited published evidence exploring the design and implementation of MHIS in these settings. This paper aims to identify and assess the key factors affecting the design and implementation of MHIS, as perceived by the key stakeholders in Ghana and South Africa. We report findings from the Mental Health and Poverty Project, a 5-year research programme implemented within four African countries. The MHIS strengthening in South Africa and Ghana included two related components: intervention and research. The intervention component aimed to strengthen MHIS in the two countries, and the research component aimed to document interventions in each country, including the key influences. Data were collected using semi structured interviews with key stakeholders and reviews of key documents and secondary data from the improved MHIS. We analyzed the qualitative data using a framework approach. Key components of the MHIS intervention involved the introduction of a redesigned patient registration form, entry into computers for analysis every 2 months by clinical managerial staff, and utilization of data in hospital management meetings in three psychiatric hospitals in Ghana; and the introduction of a new set of mental health indicators and related forms and tally sheets at primary care clinics and district hospitals in five districts in the KwaZulu-Natal and Northern Cape provinces in South Africa. Overall, the key stakeholders perceived the MHIS strengthening as an effective intervention in both countries with an enhanced set of indicators in South Africa and introduction of a computerized system in Ghana. Influences on the design and implementation of MHIS interventions in Ghana and South Africa relate to resources, working approaches (including degree of consultations during the design stage and communication during implementation stage) and the low priority of mental health. Although the influencing factors represent similar categories, more influences were identified on MHIS implementation, compared with the design stage. Different influences appear to be related within, and across, the MHIS design and implementation and may reinforce or negate each other thus leading to the multiplier or minimization effects. The wider context, similar to other studies, is important in ensuring the success of such interventions. Future MHIS strengthening interventions can consider three policy implications which emerged from our analysis and experience: enhancing consultations during the intervention design, better consideration of implementation challenges during design, and better recognition of relations between different influences.

The influence of historical climate changes on Southern Ocean marine predator populations: a comparative analysis.

PubMed

Younger, Jane L; Emmerson, Louise M; Miller, Karen J

2016-02-01

The Southern Ocean ecosystem is undergoing rapid physical and biological changes that are likely to have profound implications for higher-order predators. Here, we compare the long-term, historical responses of Southern Ocean predators to climate change. We examine palaeoecological evidence for changes in the abundance and distribution of seabirds and marine mammals, and place these into context with palaeoclimate records in order to identify key environmental drivers associated with population changes. Our synthesis revealed two key factors underlying Southern Ocean predator population changes; (i) the availability of ice-free ground for breeding and (ii) access to productive foraging grounds. The processes of glaciation and sea ice fluctuation were key; the distributions and abundances of elephant seals, snow petrels, gentoo, chinstrap and Adélie penguins all responded strongly to the emergence of new breeding habitat coincident with deglaciation and reductions in sea ice. Access to productive foraging grounds was another limiting factor, with snow petrels, king and emperor penguins all affected by reduced prey availability in the past. Several species were isolated in glacial refugia and there is evidence that refuge populations were supported by polynyas. While the underlying drivers of population change were similar across most Southern Ocean predators, the individual responses of species to environmental change varied because of species specific factors such as dispersal ability and environmental sensitivity. Such interspecific differences are likely to affect the future climate change responses of Southern Ocean marine predators and should be considered in conservation plans. Comparative palaeoecological studies are a valuable source of long-term data on species' responses to environmental change that can provide important insights into future climate change responses. This synthesis highlights the importance of protecting productive foraging grounds proximate to breeding locations, as well as the potential role of polynyas as future Southern Ocean refugia. © 2015 John Wiley & Sons Ltd.

Judicial Precedent-Based Clinical Practice Guidelines of Propofol in Sedative Esthetic Surgery.

PubMed

Lee, Duk Hee; Woo, Joo Hyun; Hong, Seung Eun

2018-06-01

Propofol is has been widely used for sedation in the field of esthetic surgery because of its favorable pharmacokinetic profile. Propofol sedation-induced side effects are rare. However, when present, they can be serious. The number of malpractice claims associated with propofol sedation has increased in recent years. This study aims to show which procedures lead to the most claims in the field of esthetic surgery through a review of Korean precedents. Thirteen precedent cases of propofol sedation in the field of esthetic surgery were collected between 2000 and 2016. We analyzed the type of procedure, administration route, anesthesia provider, complications, timing of damaging events, average indemnification, plaintiff's (patients) winning rate, ratio and the reason of limitation of liability and the key factors affecting the judgement in these cases. Most plaintiffs were women, and in most cases (11/13, 73.3%), the times of the damaging events were in maintenance and the anesthesia provider was the surgeon. The most common complication related to propofol sedation was hypoxic brain damage. Among the 13 cases, 12 were won by the plaintiff. The mean claim settlement was 339,455,814 KRW (USD 301,792.15). The key factors affecting the judgement were administration method and staff, monitoring method, preparation of emergency kit, response to emergencies, transfer to a higher-level hospital, detailed medical recording about event and informed consent. The number of claims owing to propofol sedation after esthetic surgery is increasing. Close monitoring during the operation, immediate reaction to an event and thorough medical records were main key factors that influenced the judgement. Preoperative explanation about the possibility of complications was important. The findings will help surgeons achieve high patient satisfaction and reduce liability concerns. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Women in senior post-graduate medicine career roles in the UK: a qualitative study.

PubMed

Curtis, Anthony; Eley, Lizzie; Gray, Selena; Irish, Bill

2016-01-01

This qualitative study sought to elicit the views, experiences, career journeys and aspirations of women in senior post-graduate medical education roles to identify steps needed to help support career progression. In-depth semi-structured telephone interviews. UK. Purposive sample of 12 women in a variety of senior leadership roles in post-graduate medical education in the UK. Self reported motivating influences, factors that helped and hindered progress, key branch points, and key educational factors and social support impacting on participants' career in postgraduate medicine. Respondents often reported that career journeys were serendipitous, rather than planned, formal or well structured. Senior women leaders reported having a high internal locus of control, with very high levels of commitment to the NHS. All reported significant levels of drive, although the majority indicated that they were not ambitious in the sense of a strong drive for money, prestige, recognition or power. They perceived that there was an under-representation of women in senior leadership positions and that high-quality female mentorship was particularly important in redressing this imbalance. Social support, such a spouse or other significant family member, was particularly valued as reaffirming and supporting women's chosen career ambition. Factors that were considered to have hindered career progression included low self-confidence and self-efficacy, the so-called glass ceiling and perceived self-limiting cultural influences. Factors indirectly linked to gender such as part-time versus working full time were reportedly influential in being overlooked for senior leadership roles. Implications of these findings are discussed in the paper. Social support, mentorship and role modelling are all perceived as highly important in redressing perceived gender imbalances in careers in post-graduate medical education.

Women in senior post-graduate medicine career roles in the UK: a qualitative study

PubMed Central

Curtis, Anthony; Eley, Lizzie; Irish, Bill

2016-01-01

Objectives This qualitative study sought to elicit the views, experiences, career journeys and aspirations of women in senior post-graduate medical education roles to identify steps needed to help support career progression. Design In-depth semi-structured telephone interviews. Setting UK. Participants Purposive sample of 12 women in a variety of senior leadership roles in post-graduate medical education in the UK. Main outcome measures Self reported motivating influences, factors that helped and hindered progress, key branch points, and key educational factors and social support impacting on participants' career in postgraduate medicine. Results Respondents often reported that career journeys were serendipitous, rather than planned, formal or well structured. Senior women leaders reported having a high internal locus of control, with very high levels of commitment to the NHS. All reported significant levels of drive, although the majority indicated that they were not ambitious in the sense of a strong drive for money, prestige, recognition or power. They perceived that there was an under-representation of women in senior leadership positions and that high-quality female mentorship was particularly important in redressing this imbalance. Social support, such a spouse or other significant family member, was particularly valued as reaffirming and supporting women’s chosen career ambition. Factors that were considered to have hindered career progression included low self-confidence and self-efficacy, the so-called glass ceiling and perceived self-limiting cultural influences. Factors indirectly linked to gender such as part-time versus working full time were reportedly influential in being overlooked for senior leadership roles. Implications of these findings are discussed in the paper. Conclusion Social support, mentorship and role modelling are all perceived as highly important in redressing perceived gender imbalances in careers in post-graduate medical education. PMID:28203382

Overactive Epidermal Growth Factor Receptor Signaling Leads to Increased Fibrosis after Severe Acute Respiratory Syndrome Coronavirus Infection

PubMed Central

Venkataraman, Thiagarajan; Coleman, Christopher M.

2017-01-01

ABSTRACT Severe acute respiratory syndrome coronavirus (SARS-CoV) is a highly pathogenic respiratory virus that causes morbidity and mortality in humans. After infection with SARS-CoV, the acute lung injury caused by the virus must be repaired to regain lung function. A dysregulation in this wound healing process leads to fibrosis. Many survivors of SARS-CoV infection develop pulmonary fibrosis (PF), with higher prevalence in older patients. Using mouse models of SARS-CoV pathogenesis, we have identified that the wound repair pathway, controlled by the epidermal growth factor receptor (EGFR), is critical to recovery from SARS-CoV-induced tissue damage. In mice with constitutively active EGFR [EGFR(DSK5) mice], we find that SARS-CoV infection causes enhanced lung disease. Importantly, we show that during infection, the EGFR ligands amphiregulin and heparin-binding EGF-like growth factor (HB-EGF) are upregulated, and exogenous addition of these ligands during infection leads to enhanced lung disease and altered wound healing dynamics. Our data demonstrate a key role of EGFR in the host response to SARS-CoV and how it may be implicated in lung disease induced by other highly pathogenic respiratory viruses. IMPORTANCE PF has many causative triggers, including severe respiratory viruses such as SARS-CoV. Currently there are no treatments to prevent the onset or limit the progression of PF, and the molecular pathways underlying the development of PF are not well understood. In this study, we identified a role for the balanced control of EGFR signaling as a key factor in progression to PF. These data demonstrate that therapeutic treatment modulating EGFR activation could protect against PF development caused by severe respiratory virus infection. PMID:28404843

Overactive Epidermal Growth Factor Receptor Signaling Leads to Increased Fibrosis after Severe Acute Respiratory Syndrome Coronavirus Infection.

PubMed

Venkataraman, Thiagarajan; Coleman, Christopher M; Frieman, Matthew B

2017-06-15

Severe acute respiratory syndrome coronavirus (SARS-CoV) is a highly pathogenic respiratory virus that causes morbidity and mortality in humans. After infection with SARS-CoV, the acute lung injury caused by the virus must be repaired to regain lung function. A dysregulation in this wound healing process leads to fibrosis. Many survivors of SARS-CoV infection develop pulmonary fibrosis (PF), with higher prevalence in older patients. Using mouse models of SARS-CoV pathogenesis, we have identified that the wound repair pathway, controlled by the epidermal growth factor receptor (EGFR), is critical to recovery from SARS-CoV-induced tissue damage. In mice with constitutively active EGFR [EGFR(DSK5) mice], we find that SARS-CoV infection causes enhanced lung disease. Importantly, we show that during infection, the EGFR ligands amphiregulin and heparin-binding EGF-like growth factor (HB-EGF) are upregulated, and exogenous addition of these ligands during infection leads to enhanced lung disease and altered wound healing dynamics. Our data demonstrate a key role of EGFR in the host response to SARS-CoV and how it may be implicated in lung disease induced by other highly pathogenic respiratory viruses. IMPORTANCE PF has many causative triggers, including severe respiratory viruses such as SARS-CoV. Currently there are no treatments to prevent the onset or limit the progression of PF, and the molecular pathways underlying the development of PF are not well understood. In this study, we identified a role for the balanced control of EGFR signaling as a key factor in progression to PF. These data demonstrate that therapeutic treatment modulating EGFR activation could protect against PF development caused by severe respiratory virus infection. Copyright © 2017 American Society for Microbiology.

Regulation of cotton (Gossypium hirsutum) drought responses by mitogen-activated protein (MAP) kinase cascade-mediated phosphorylation of GhWRKY59.

PubMed

Li, Fangjun; Li, Maoying; Wang, Ping; Cox, Kevin L; Duan, Liusheng; Dever, Jane K; Shan, Libo; Li, Zhaohu; He, Ping

2017-09-01

Drought is a key limiting factor for cotton (Gossypium spp.) production, as more than half of the global cotton supply is grown in regions with high water shortage. However, the underlying mechanism of the response of cotton to drought stress remains elusive. By combining genome-wide transcriptome profiling and a loss-of-function screen using virus-induced gene silencing, we identified Gossypium hirsutum GhWRKY59 as an important transcription factor that regulates the drought stress response in cotton. Biochemical and genetic analyses revealed a drought stress-activated mitogen-activated protein (MAP) kinase cascade consisting of GhMAP3K15-Mitogen-activated Protein Kinase Kinase 4 (GhMKK4)-Mitogen-activated Protein Kinase 6 (GhMPK6) that directly phosphorylates GhWRKY59 at residue serine 221. Interestingly, GhWRKY59 is required for dehydration-induced expression of GhMAPK3K15, constituting a positive feedback loop of GhWRKY59-regulated MAP kinase activation in response to drought stress. Moreover, GhWRKY59 directly binds to the W-boxes of DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 2 (GhDREB2), which encodes a dehydration-inducible transcription factor regulating the plant hormone abscisic acid (ABA)-independent drought response. Our study identified a complete MAP kinase cascade that phosphorylates and activates a key WRKY transcription factor, and elucidated a regulatory module, consisting of GhMAP3K15-GhMKK4-GhMPK6-GhWRKY59-GhDREB2, that is involved in controlling the cotton drought response. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

An essential role for IL-2 receptor in regulatory T cell function

PubMed Central

Levine, Andrew G; Fan, Xiying; Klein, Ulf; Zheng, Ye; Gasteiger, Georg; Feng, Yongqiang; Fontenot, Jason D.; Rudensky, Alexander Y.

2016-01-01

Regulatory T (Treg) cells, expressing abundant amounts of the IL-2 receptor (IL-2R), are reliant on IL-2 produced by activated T cells. This feature implied a key role for a simple network based on IL-2 consumption by Treg cells in their suppressor function. However, congenital deficiency in IL-2R results in reduced expression of the Treg cell lineage specification factor Foxp3, confounding experimental efforts to understand the role of IL-2R expression and signaling in Treg suppressor function. Using genetic gain and loss of function approaches, we demonstrate that IL-2 capture is dispensable for control of CD4+ T cells, but is important for limiting CD8+ T cell activation, and that IL-2R dependent STAT5 transcription factor activation plays an essential role in Treg cell suppressor function separable from T cell receptor signaling. PMID:27595233

Context-based Strategies for Engaging Consumers with Public Reports about Health Care Providers

PubMed Central

Shaller, Dale; Kanouse, David E.; Schlesinger, Mark

2017-01-01

Efforts to engage consumers in the use of public reports on health care provider performance have met with limited success. Fostering greater engagement will require new approaches that provide consumers with relevant content at the time and in the context they need to make a decision of consequence. To this end, we identify three key factors influencing consumer engagement and show how they manifest in different ways and combinations for four particular choice contexts that appear to offer realistic opportunities for engagement. We analyze how these engagement factors play out differently in each choice context and suggest specific strategies that sponsors of public reports can use in each context. Cross-cutting lessons for report sponsors and policy makers include new media strategies such as a commitment to adaptive web-based reporting, new metrics with richer emotional content, and the use of navigators or advocates to assist consumers with interpreting reports. PMID:23819945

Understanding the Key to Targeting the IGF Axis in Cancer: A Biomarker Assessment

PubMed Central

Lodhia, Kunal Amratlal; Tienchaiananda, Piyawan; Haluska, Paul

2015-01-01

Type 1 insulin like growth factor receptor (IGF-1R) targeted therapies showed compelling pre-clinical evidence; however, to date, this has failed to translate into patient benefit in Phase 2/3 trials in unselected patients. This was further complicated by the toxicity, including hyperglycemia, which largely results from the overlap between IGF and insulin signaling systems and associated feedback mechanisms. This has halted the clinical development of inhibitors targeting IGF signaling, which has limited the availability of biopsy samples for correlative studies to understand biomarkers of response. Indeed, a major factor contributing to lack of clinical benefit of IGF targeting agents has been difficulty in identifying patients with tumors driven by IGF signaling due to the lack of predictive biomarkers. In this review, we will describe the IGF system, rationale for targeting IGF signaling, the potential liabilities of targeting strategies, and potential biomarkers that may improve success. PMID:26217584

Key ecological responses to nitrogen are altered by climate ...

EPA Pesticide Factsheets

Here we review the effects of nitrogen and climate (e.g. temperature and precipitation) on four aspects of ecosystem structure and function including hydrologic-coupled nitrogen cycling, carbon cycling, acidification and biodiversity. Ecosystems are simultaneously exposed to multiple stressors; two dominant drivers threatening ecosystems are anthropogenic nitrogen loading and climate change. Evaluating the cumulative effects of these stressors provides a holistic view of ecosystem vulnerability, which would better inform policy decisions aimed to protect the sustainability of ecosystems. Our current knowledge of the cumulative effects of these stressors is growing, but limited. The goal of this paper is to synthesize the state of scientific knowledge on how ecosystems are affected by the interactions of meteorlogic/climatic factors (e.g., temperature and precipitation) and nitrogen addition. Understanding the interactions of meteorlogic/climatic factors and nitrogen will help to inform how current and projected variability may affect ecosystem response.

Advances in recurrence and malignant transformation of sinonasal inverted papillomas

PubMed Central

Sun, Qingjia; An, Lifeng; Zheng, Jun; Zhu, Dongdong

2017-01-01

Sinonasal inverted papilloma (SIP) is a benign tumor of the nasal cavity and sinus. SIP is characterized by aggressive malignant transformation and a high rate of recurrence. Inadequate removal of the tumor during surgery is one of the most significant contributors to SIP recurrence. A growing body of evidence suggests that molecular alteration in SIP, including human papilloma virus infections, single nucleotide polymorphisms of key genes, deregulation of signaling pathways and immunological changes, may lead to SIP occurrence and malignant transformation. However, the extent to which these molecular mechanisms contribute to SIP pathology and transformation remains unclear due to limited research. Further studies are warranted to elucidate the primary dependent factors that contribute to SIP etiology. The present article reviewed risk factors of progression and recurrence of SIP, including outdoor and industrial occupational exposure, smoking, septal deviation, SIP location, recurrent cases, stage of SIP-associated squamous cell carcinoma and choice of surgical method. PMID:28599459

Achieving QoS for TCP Traffic in Satellite Networks with Differentiated Services

NASA Technical Reports Server (NTRS)

Durresi, Arjan; Kota, Sastri; Goyal, Mukul; Jain, Raj; Bharani, Venkata

2001-01-01

Satellite networks play an indispensable role in providing global Internet access and electronic connectivity. To achieve such a global communications, provisioning of quality of service (QoS) within the advanced satellite systems is the main requirement. One of the key mechanisms of implementing the quality of service is traffic management. Traffic management becomes a crucial factor in the case of satellite network because of the limited availability of their resources. Currently, Internet Protocol (IP) only has minimal traffic management capabilities and provides best effort services. In this paper, we presented a broadband satellite network QoS model and simulated performance results. In particular, we discussed the TCP flow aggregates performance for their good behavior in the presence of competing UDP flow aggregates in the same assured forwarding. We identified several factors that affect the performance in the mixed environments and quantified their effects using a full factorial design of experiment methodology.

Challenging ocular image recognition

NASA Astrophysics Data System (ADS)

Pauca, V. Paúl; Forkin, Michael; Xu, Xiao; Plemmons, Robert; Ross, Arun A.

2011-06-01

Ocular recognition is a new area of biometric investigation targeted at overcoming the limitations of iris recognition performance in the presence of non-ideal data. There are several advantages for increasing the area beyond the iris, yet there are also key issues that must be addressed such as size of the ocular region, factors affecting performance, and appropriate corpora to study these factors in isolation. In this paper, we explore and identify some of these issues with the goal of better defining parameters for ocular recognition. An empirical study is performed where iris recognition methods are contrasted with texture and point operators on existing iris and face datasets. The experimental results show a dramatic recognition performance gain when additional features are considered in the presence of poor quality iris data, offering strong evidence for extending interest beyond the iris. The experiments also highlight the need for the direct collection of additional ocular imagery.

A preliminary analysis of incident investigation reports of an integrated steel plant: some reflection.

PubMed

Verma, A; Maiti, J; Gaikwad, V N

2018-06-01

Large integrated steel plants employ an effective safety management system and gather a significant amount of safety-related data. This research intends to explore and visualize the rich database to find out the key factors responsible for the occurrences of incidents. The study was carried out on the data in the form of investigation reports collected from a steel plant in India. The data were processed and analysed using some of the quality management tools like Pareto chart, control chart, Ishikawa diagram, etc. Analyses showed that causes of incidents differ depending on the activities performed in a department. For example, fire/explosion and process-related incidents are more common in the departments associated with coke-making and blast furnace. Similar kind of factors were obtained, and recommendations were provided for their mitigation. Finally, the limitations of the study were discussed, and the scope of the research works was identified.

Final report of the APMP water flow key comparison: APMP.M.FF-K1

NASA Astrophysics Data System (ADS)

Lee, Kwang-Bock; Chun, Sejong; Terao, Yoshiya; Thai, Nguyen Hong; Tsair Yang, Cheng; Tao, Meng; Gutkin, Mikhail B.

2011-01-01

The key comparison, APMP.M.FF-K1, was undertaken by APMP/TCFF, the Technical Committee for Fluid Flow (TCFF) under the Asia Pacific Metrology Program (APMP). One objective of the key comparison was to demonstrate the degree of equivalence among six participating laboratories (KRISS, NMIJ, VMI, CMS, NIM and VNIIM) in water flow rate metrology by comparing the results with the key comparison reference value (KCRV) determined from the CCM.FF-K1 key comparison. The other objective of this key comparison was to provide supporting evidence for the calibration and measurement capabilities (CMCs), which had been declared by the participating laboratories during this key comparison. The Transfer Standard Package (TSP) was a Coriolis mass flowmeter, which had been used in the CCM.FF-K1 key comparison. Because the K-factors in the APMP.M.FF-K1 key comparison were slightly lower than the K-factors of the CCM.FF-K1 key comparison due to long-term drifts of the TSP, a correction value D was introduced. The value of D was given by a weighted sum between two link laboratories (NMIJ and KRISS), which participated in both the CCM.FF-K1 and the APMP.M.FF-K1 key comparisons. By this correction, the K-factors were laid between 12.004 and 12.017 at either low (Re = 254 000) or high (Re = 561 000) flow rates. Most of the calibration data were within expected uncertainty bounds. However, some data showed undulations, which gave large fluctuations of the metering factor at Re = 561 000. Calculation of degrees of equivalence showed that all the participating laboratories had deviations between -0.009 and 0.007 pulses/kg from the CCM.FF-K1 KCRV at either the low or the high flow rates. In case of En calculation, all the participating laboratories showed values less than 1, indicating that the corrected K-factors of all the laboratories were equivalent with the KCRV at both Re = 254 000 and 561 000. When the corrected K-factors from two participating laboratories were compared, all the numbers of equivalence showed values less than 1, indicating equivalence. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

Factors Influencing the Prescribing Preferences of Physicians for Drug-Naive Patients with Type 2 Diabetes Mellitus in the Real-World Setting in Japan: Insight from a Web Survey.

PubMed

Murayama, Hiroki; Imai, Kota; Odawara, Masato

2018-06-01

The Japanese guidelines for type 2 diabetes mellitus (T2DM) emphasize individualization of treatment based on patient need and encourage physicians to select an appropriate oral antidiabetes drug (OAD). However, limited evidence is available on the factors influencing the selection by physicians (diabetes specialists and nonspecialists) of the first-line OAD to treat drug-naive patients with T2DM. A survey was designed to explore the treatment factors and patient characteristics that influence physicians when they choose an initial OAD to prescribe to a drug-naive patient with T2DM in a real-world setting in Japan. The 25-min web-based online survey consisted of simple and focused multiple-choice questions, and was circulated to physicians across eight selected regions in Japan. The primary endpoints were the proportions of physicians who considered particular treatment factors and patient characteristics when selecting the appropriate treatment for drug-naive T2DM patients. A total of 491 physicians participated in the survey. Dipeptidyl peptidase-4 inhibitors (DPP-4is) were the most-preferred first-line OADs, followed by metformin, of both specialists (69% vs. 60%) and nonspecialists (73% vs. 47%). The most influential factors when a DPP-4i was selected were found to be glycated hemoglobin (HbA1c), postprandial glucose (PPG)-lowering effect, and a low risk of hypoglycemia, which were considered by > 80% of physicians, whereas the key factors when metformin was selected were improvement in insulin resistance, low cost, low risk of hypoglycemia, and PPG- and HbA1c-lowering effects, which were considered by > 85% of physicians. Regression analysis revealed that the dominant reason for choosing DPP-4is over metformin was their ease of use in patients with renal impairment, whereas the dominant reasons for choosing metformin over DPP-4is were improvement in insulin resistance and low cost. The key patient characteristics driving the choice of DPP-4is or metformin as the first-line OAD by physicians were similar to those that influenced the treatment intensification decision (DPP-4is: PPG and renal function; metformin: age, BMI, insulin resistance, and renal function). In Japan, DPP-4is are the preferred first-line OADs, followed by metformin. The key treatment factors and patient characteristics considered when selecting DPP-4is or metformin are similar for both specialists and nonspecialists. These results may prompt further discussion of the differences in T2DM treatment between Japan and other counties. Novartis.

Response of Southern Ocean Phytoplankton Communities to Trace Metal (including Iron) and Light Availability

NASA Astrophysics Data System (ADS)

Fietz, S.; Roychoudhury, A. N.; Thomalla, S.; Mtshali, T. N.; Philibert, R.; Van Horsten, N.; Loock, J. C.; Cloete, R.

2016-02-01

Phytoplankton primary productivity depends on macro- and micronutrient availability and in turn plays a key role in the marine biogeochemical cycles. The role of iron in regulating phytoplankton primary production and thus biogeochemical cycles in the Southern Ocean has been widely recognized; however, it also became obvious that iron is not the sole factor limiting primary production in the Southern Ocean and that light, for instance, might aggravate or relief trace nutrient limitation. We conducted a suite of ship-board incubation experiments in austral summer 2013/14, 2014/15 and winter 2015 to shed light on the complex interplay between trace metal and light limitation. We observed a strong difference in acclimation and photophysiological response depending on the environmental conditions of the in-situ communities prior to the experiment. The differences in acclimation and photophysiological responses resulted in different growth and macronutrient uptake rates. Revisited stations did, however, not always show the same responses. At at least one station we will link the incubation experiments to the in-situ vertical profiles of trace metals, macronutrients and primary productivity.

Effect of hysteretic and non-hysteretic negative capacitance on tunnel FETs DC performance

NASA Astrophysics Data System (ADS)

Saeidi, Ali; Jazaeri, Farzan; Stolichnov, Igor; Luong, Gia V.; Zhao, Qing-Tai; Mantl, Siegfried; Ionescu, Adrian M.

2018-03-01

This work experimentally demonstrates that the negative capacitance effect can be used to significantly improve the key figures of merit of tunnel field effect transistor (FET) switches. In the proposed approach, a matching condition is fulfilled between a trained-polycrystalline PZT capacitor and the tunnel FET (TFET) gate capacitance fabricated on a strained silicon-nanowire technology. We report a non-hysteretic switch configuration by combining a homojunction TFET and a negative capacitance effect booster, suitable for logic applications, for which the on-current is increased by a factor of 100, the transconductance by 2 orders of magnitude, and the low swing region is extended. The operation of a hysteretic negative capacitance TFET, when the matching condition for the negative capacitance is fulfilled only in a limited region of operation, is also reported and discussed. In this late case, a limited improvement in the device performance is observed. Overall, the paper demonstrates the main beneficial effects of negative capacitance on TFETs are the overdrive and transconductance amplification, which exactly address the most limiting performances of current TFETs.

Statistical Inference and Simulation with StatKey

ERIC Educational Resources Information Center

Quinn, Anne

2016-01-01

While looking for an inexpensive technology package to help students in statistics classes, the author found StatKey, a free Web-based app. Not only is StatKey useful for students' year-end projects, but it is also valuable for helping students learn fundamental content such as the central limit theorem. Using StatKey, students can engage in…

Part II--Factors Associated with School Nurse Ratios: Key State Informants' Perceptions

ERIC Educational Resources Information Center

Maughan, Erin

2009-01-01

This paper is the second of a two-part series examining factors influencing school nurse to pupil staffing ratios. The paper reports data from a qualitative study exploring the social and political factors that potentially influence ratios. Interviews were conducted with 30 key state informants from these states. Content analysis of the data…

Increased production of functional recombinant human clotting factor IX by baby hamster kidney cells engineered to overexpress VKORC1, the vitamin K 2,3-epoxide-reducing enzyme of the vitamin K cycle.

PubMed

Wajih, Nadeem; Hutson, Susan M; Owen, John; Wallin, Reidar

2005-09-09

Some recombinant vitamin K-dependent blood coagulation factors (factors VII, IX, and protein C) have become valuable pharmaceuticals in the treatment of bleeding complications and sepsis. Because of their vitamin K-dependent post-translational modification, their synthesis by eukaryotic cells is essential. The eukaryotic cell harbors a vitamin K-dependent gamma-carboxylation system that converts the proteins to gamma-carboxyglutamic acid-containing proteins. However, the system in eukaryotic cells has limited capacity, and cell lines overexpressing vitamin K-dependent clotting factors produce only a fraction of the recombinant proteins as fully gamma-carboxylated, physiologically competent proteins. In this work we have used recombinant human factor IX (r-hFIX)-producing baby hamster kidney (BHK) cells, engineered to stably overexpress various components of the gamma-carboxylation system of the cell, to determine whether increased production of functional r-hFIX can be accomplished. All BHK cell lines secreted r-hFIX into serum-free medium. Overexpression of gamma-carboxylase is shown to inhibit production of functional r-hFIX. On the other hand, cells overexpressing VKORC1, the reduced vitamin K cofactor-producing enzyme of the vitamin K-dependent gamma-carboxylation system, produced 2.9-fold more functional r-hFIX than control BHK cells. The data are consistent with the notion that VKORC1 is the rate-limiting step in the system and is a key regulatory protein in synthesis of active vitamin K-dependent proteins. The data suggest that overexpression of VKORC1 can be utilized for increased cellular production of recombinant vitamin K-dependent proteins.

Experimental quantum key distribution with simulated ground-to-satellite photon losses and processing limitations

NASA Astrophysics Data System (ADS)

Bourgoin, Jean-Philippe; Gigov, Nikolay; Higgins, Brendon L.; Yan, Zhizhong; Meyer-Scott, Evan; Khandani, Amir K.; Lütkenhaus, Norbert; Jennewein, Thomas

2015-11-01

Quantum key distribution (QKD) has the potential to improve communications security by offering cryptographic keys whose security relies on the fundamental properties of quantum physics. The use of a trusted quantum receiver on an orbiting satellite is the most practical near-term solution to the challenge of achieving long-distance (global-scale) QKD, currently limited to a few hundred kilometers on the ground. This scenario presents unique challenges, such as high photon losses and restricted classical data transmission and processing power due to the limitations of a typical satellite platform. Here we demonstrate the feasibility of such a system by implementing a QKD protocol, with optical transmission and full post-processing, in the high-loss regime using minimized computing hardware at the receiver. Employing weak coherent pulses with decoy states, we demonstrate the production of secure key bits at up to 56.5 dB of photon loss. We further illustrate the feasibility of a satellite uplink by generating a secure key while experimentally emulating the varying losses predicted for realistic low-Earth-orbit satellite passes at 600 km altitude. With a 76 MHz source and including finite-size analysis, we extract 3374 bits of a secure key from the best pass. We also illustrate the potential benefit of combining multiple passes together: while one suboptimal "upper-quartile" pass produces no finite-sized key with our source, the combination of three such passes allows us to extract 165 bits of a secure key. Alternatively, we find that by increasing the signal rate to 300 MHz it would be possible to extract 21 570 bits of a secure finite-sized key in just a single upper-quartile pass.

In silico mining and PCR-based approaches to transcription factor discovery in non-model plants: gene discovery of the WRKY transcription factors in conifers.

PubMed

Liu, Jun-Jun; Xiang, Yu

2011-01-01

WRKY transcription factors are key regulators of numerous biological processes in plant growth and development, as well as plant responses to abiotic and biotic stresses. Research on biological functions of plant WRKY genes has focused in the past on model plant species or species with largely characterized transcriptomes. However, a variety of non-model plants, such as forest conifers, are essential as feed, biofuel, and wood or for sustainable ecosystems. Identification of WRKY genes in these non-model plants is equally important for understanding the evolutionary and function-adaptive processes of this transcription factor family. Because of limited genomic information, the rarity of regulatory gene mRNAs in transcriptomes, and the sequence divergence to model organism genes, identification of transcription factors in non-model plants using methods similar to those generally used for model plants is difficult. This chapter describes a gene family discovery strategy for identification of WRKY transcription factors in conifers by a combination of in silico-based prediction and PCR-based experimental approaches. Compared to traditional cDNA library screening or EST sequencing at transcriptome scales, this integrated gene discovery strategy provides fast, simple, reliable, and specific methods to unveil the WRKY gene family at both genome and transcriptome levels in non-model plants.

14 CFR 27.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 27.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

14 CFR 29.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 29.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

An Efficient Identity-Based Key Management Scheme for Wireless Sensor Networks Using the Bloom Filter

PubMed Central

Qin, Zhongyuan; Zhang, Xinshuai; Feng, Kerong; Zhang, Qunfang; Huang, Jie

2014-01-01

With the rapid development and widespread adoption of wireless sensor networks (WSNs), security has become an increasingly prominent problem. How to establish a session key in node communication is a challenging task for WSNs. Considering the limitations in WSNs, such as low computing capacity, small memory, power supply limitations and price, we propose an efficient identity-based key management (IBKM) scheme, which exploits the Bloom filter to authenticate the communication sensor node with storage efficiency. The security analysis shows that IBKM can prevent several attacks effectively with acceptable computation and communication overhead. PMID:25264955

A more secure parallel keyed hash function based on chaotic neural network

NASA Astrophysics Data System (ADS)

Huang, Zhongquan

2011-08-01

Although various hash functions based on chaos or chaotic neural network were proposed, most of them can not work efficiently in parallel computing environment. Recently, an algorithm for parallel keyed hash function construction based on chaotic neural network was proposed [13]. However, there is a strict limitation in this scheme that its secret keys must be nonce numbers. In other words, if the keys are used more than once in this scheme, there will be some potential security flaw. In this paper, we analyze the cause of vulnerability of the original one in detail, and then propose the corresponding enhancement measures, which can remove the limitation on the secret keys. Theoretical analysis and computer simulation indicate that the modified hash function is more secure and practical than the original one. At the same time, it can keep the parallel merit and satisfy the other performance requirements of hash function, such as good statistical properties, high message and key sensitivity, and strong collision resistance, etc.

Evaluation of Limiting Climatic Factors and Simulation of a Climatically Suitable Habitat for Chinese Sea Buckthorn

PubMed Central

Li, Guoqing; Du, Sheng; Guo, Ke

2015-01-01

Chinese sea buckthorn (Hippophae rhamnoides subsp. sinensis) has considerable economic potential and plays an important role in reclamation and soil and water conservation. For scientific cultivation of this species across China, we identified the key climatic factors and explored climatically suitable habitat in order to maximize survival of Chinese sea buckthorn using MaxEnt and GIS tools, based on 98 occurrence records from herbarium and publications and 13 climatic factors from Bioclim, Holdridge life zone and Kria' index variables. Our simulation showed that the MaxEnt model performance was significantly better than random, with an average test AUC value of 0.93 with 10-fold cross validation. A jackknife test and the regularized gain change, which were applied to the training algorithm, showed that precipitation of the driest month (PDM), annual precipitation (AP), coldness index (CI) and annual range of temperature (ART) were the most influential climatic factors in limiting the distribution of Chinese sea buckthorn, which explained 70.1% of the variation. The predicted map showed that the core of climatically suitable habitat was distributed from the southwest to northwest of Gansu, Ningxia, Shaanxi and Shanxi provinces, where the most influential climate variables were PDM of 1.0–7.0 mm, AP of 344.0–1089.0 mm, CI of -47.7–0.0°C, and ART of 26.1–45.0°C. We conclude that the distribution patterns of Chinese sea buckthorn are related to the northwest winter monsoon, the southwest summer monsoon and the southeast summer monsoon systems in China. PMID:26177033

Evaluation of Limiting Climatic Factors and Simulation of a Climatically Suitable Habitat for Chinese Sea Buckthorn.

PubMed

Li, Guoqing; Du, Sheng; Guo, Ke

2015-01-01

Chinese sea buckthorn (Hippophae rhamnoides subsp. sinensis) has considerable economic potential and plays an important role in reclamation and soil and water conservation. For scientific cultivation of this species across China, we identified the key climatic factors and explored climatically suitable habitat in order to maximize survival of Chinese sea buckthorn using MaxEnt and GIS tools, based on 98 occurrence records from herbarium and publications and 13 climatic factors from Bioclim, Holdridge life zone and Kria' index variables. Our simulation showed that the MaxEnt model performance was significantly better than random, with an average test AUC value of 0.93 with 10-fold cross validation. A jackknife test and the regularized gain change, which were applied to the training algorithm, showed that precipitation of the driest month (PDM), annual precipitation (AP), coldness index (CI) and annual range of temperature (ART) were the most influential climatic factors in limiting the distribution of Chinese sea buckthorn, which explained 70.1% of the variation. The predicted map showed that the core of climatically suitable habitat was distributed from the southwest to northwest of Gansu, Ningxia, Shaanxi and Shanxi provinces, where the most influential climate variables were PDM of 1.0-7.0 mm, AP of 344.0-1089.0 mm, CI of -47.7-0.0°C, and ART of 26.1-45.0°C. We conclude that the distribution patterns of Chinese sea buckthorn are related to the northwest winter monsoon, the southwest summer monsoon and the southeast summer monsoon systems in China.

Cognitive and Family Correlates of Current Suicidal Ideation in Children with Bipolar Disorder

PubMed Central

Weinstein, Sally M.; Van Meter, Anna; Katz, Andrea C.; Peters, Amy T.; West, Amy E.

2014-01-01

Background Suicidality among youth with bipolar disorder is an extreme, but largely unaddressed, public health problem. The current study examined the psychosocial characteristics differentiating youth with varying severities of suicidal ideation that may dictate targets for suicide prevention interventions. Methods Participants included 72 youth aged 7–13 (M = 9.19, SD = 1.61) with DSM-IV-TR bipolar I, II, or NOS and a parent/caregiver. Current suicidal ideation and correlates were assessed at intake, including: demographics and clinical factors (diagnosis, symptom severity, psychiatric comorbidity); child factors (cognitive risk and quality of life); and family factors (parenting stress, family cohesion, and family rigidity). Results Current ideation was prevalent in this young sample: 41% endorsed any ideation, and 31% endorsed active forms. Depression symptoms, quality of life, hopelessness, self-esteem, and family rigidity differentiated youth with increasing ideation severity. Separate logistic regressions examined all significant child- and family-level factors, controlling for demographic and clinical variables. Greater family rigidity and lower self-esteem remained significant predictors of current planful ideation. Diagnosis, index episode, comorbidity, and mania severity did not differentiate non-ideators from those with current ideation. Limitations Limitations include the small sample to examine low base-rate severe ideation, cross-sectional analyses and generalizability of findings beyond the outpatient clinical sample. Conclusions Findings underscore the importance of assessing and addressing suicidality in preadolescent youth with bipolar disorder, before youth progress to more severe suicidal behaviors. Results also highlight child self-esteem and family rigidity as key treatment targets to reduce suicide risk in pediatric bipolar disorder. PMID:25462390

Structural equation modelling of lower back pain due to whole-body vibration exposure in the construction industry.

PubMed

Vitharana, Vitharanage Hashini Paramitha; Chinda, Thanwadee

2017-09-21

Whole-body vibration (WBV) exposure is a health hazard among workers, causing lower back pain (LBP) in the construction industry. This study examines key factors affecting LBP due to WBV exposure using exploratory factor analysis and structural equation modelling. The results confirm five key factors (equipment, job related, organizational, personal, social context) with their 17 associated items. The organizational factor is found the most important, as it influences the other four factors. The results also show that appropriate seat type, specific training programme, job rotation, workers' satisfaction and workers' physical condition are crucial in reducing LBP due to WBV exposure. Moreover, provision of new machines without proper training and good working condition might not help reduce LBP due to WBV exposure. The results help the construction companies to better understand key factors affecting LBP due to WBV exposure, and to plan for a better health improvement programme.

Variation in style morph frequencies in tristylous Lythrum salicaria in the Iberian Peninsula: the role of geographical and demographic factors

PubMed Central

Costa, Joana; Castro, Sílvia; Loureiro, João; Barrett, Spencer C. H.

2016-01-01

Background and Aims The balance between stochastic forces and negative frequency-dependent selection largely determines style morph frequencies in heterostylous populations. Investigation of morph frequencies at geographical range limits can provide insights into the forces maintaining the floral polymorphism, and the factors causing biased morph ratios. Here, we investigate style morph frequencies in populations at the south-western European range limit of tristylous Lythrum salicaria, to explore the role of demographic and geographical factors influencing morph ratios in its native range. Methods We measured morph composition and evenness, and the size of 96 populations, along a north to south latitudinal transect from Galicia to Andalucia, Iberian Peninsula, traversing a steep climatic gradient. To examine the potential influence of morph-specific fitness components on morph ratios, we examined reproductive traits in 19 populations. Key Results Most populations of L. salicaria were trimorphic (94·79 %), the majority exhibiting 1 : 1 : 1 morph ratios (68·75 %). Populations with biased morph ratios had a deficiency of the short-styled morph. Population size and morph evenness were positively associated with latitude, with smaller populations and those with less even morph ratios occurring towards the south. Greater variance in morph evenness was evident at the southern range margin. There were no consistent differences in components of reproductive fitness among style morphs, but southern populations produced less fruit and seed than more northerly populations. Conclusions Our results demonstrate the influence of finite population size on morph frequencies in L. salicaria. However, they also illustrate the resilience of Iberian populations to the factors causing deviations from isoplethy and morph loss, especially at the southern range limit where populations are smaller. The maintenance of tristyly in small populations of L. salicaria may be aided by the genetic connectivity of populations in agricultural landscapes resulting from gene flow through pollen and seed dispersal. PMID:26658100

Shifting Environmental Ranges and Biome Potential According to the Whittaker Relationship

NASA Astrophysics Data System (ADS)

de Jong, R.; Garonna, I.; Schaepman, M. E.

2015-12-01

Robert H. Whittaker classified biome types mainly as a function of Mean Annual Temperature (MAT) and Mean Annual Precipitation (MAP), resulting in the well-known Whittaker plot1. This relationship is still being used to map biomes globally2. The same inputs (MAT and MAP), augmented with a radiation proxy, are used in the resource-balance perspective for modeling large-scale vegetation productivity as a function of abiotic factors3. These two approaches, used in a temporally dynamic manner, provided us indicators of shifts in growth-limiting factors4 and associated environmental ranges of vegetation, which, in turn, are key indicators for the study of global change and biodiversity5. We present a study in which we used the Whittaker relationship and CRU TS 3.22 climatic data to map regions that showed variable biome potential. These regions are likely to indicate ecotones - i.e. interactions zones between biomes - that have been subject to abiotic change and where a change in the vegetation system can be anticipated. At the same time, we used remotely sensed data (GIMMS v3g 1982-2012) to study gradients in vegetation dynamics in these zones. Preliminary results show strongest environmental shifts in northern ecotones, e.g. on the tundra - boreal boundary, and associated changes in climatic growth-limiting factors4. [1] Whittaker RH (1975) Communities and Ecosystems, Macmillan, 385p.[2] Ricklefs RE (2008) The Economy of Nature, W. H. Freeman, 620p.[3] Field CB, Randerson JT, Malmström CM (1995) Global net primary production: Combining ecology and remote sensing. Remote Sensing of Environment, 51, 74-88.[4] Schenkel D, Garonna I, De Jong R, Schaepman ME (this conference) Linking Land Surface Phenology and Growth Limiting Factor Shifts over the Past 30 Years.[5] University of Zurich Research Priority Program on Global Change and Biodiversity, http://www.gcb.uzh.ch

Factors influencing the career interest of medical graduates in obstetrics and gynaecology in Hong Kong: a cross-sectional questionnaire survey.

PubMed

Lam, Christy Y Y; Cheung, Charleen S Y; Hui, Annie S Y

2016-04-01

The trend of declining interest of medical graduates in pursuing obstetrics and gynaecology as a career has been observed in many overseas studies. This study aimed to evaluate the career interest of the most recent medical graduates in Hong Kong, especially their level of interest in obstetrics and gynaecology, and to identify key influential factors for career choice and career interest in obstetrics and gynaecology. All medical graduates from the Chinese University of Hong Kong and the University of Hong Kong who attended the pre-internship lectures in June 2015 were invited to participate in this cross-sectional questionnaire survey. The main outcome measures were the level of career interest in obstetrics and gynaecology, the first three choices of specialty as a career, key influential factors for career choice, and key influential factors for career interest in obstetrics and gynaecology. Overall, 73.7% of 323 new medical graduates participated in the study and 233 questionnaires were analysed. The median score (out of 10) for the level of career interest in obstetrics and gynaecology was 3. There were 37 (16.2%) participants in whom obstetrics and gynaecology was among their first three choices, of whom 29 (78.4%) were female. Obstetrics and gynaecology ranked as the eighth most popular career choice. By factor analysis, the strongest key influential factor for career interest in obstetrics and gynaecology was clerkship experience (variance explained 28.9%) and the strongest key influential factor for career choice was working style (variance explained 26.4%). The study confirmed a low level of career interest in obstetrics and gynaecology among medical graduates and a decreasing popularity of the specialty as a career choice. The three key influential factors for career interest in obstetrics and gynaecology and career choice were working style, clerkship experience, and career prospects.

ATG5 overexpression is neuroprotective and attenuates cytoskeletal and vesicle-trafficking alterations in axotomized motoneurons.

PubMed

Leiva-Rodríguez, Tatiana; Romeo-Guitart, David; Marmolejo-Martínez-Artesero, Sara; Herrando-Grabulosa, Mireia; Bosch, Assumpció; Forés, Joaquim; Casas, Caty

2018-05-24

Injured neurons should engage endogenous mechanisms of self-protection to limit neurodegeneration. Enhancing efficacy of these mechanisms or correcting dysfunctional pathways may be a successful strategy for inducing neuroprotection. Spinal motoneurons retrogradely degenerate after proximal axotomy due to mechanical detachment (avulsion) of the nerve roots, and this limits recovery of nervous system function in patients after this type of trauma. In a previously reported proteomic analysis, we demonstrated that autophagy is a key endogenous mechanism that may allow motoneuron survival and regeneration after distal axotomy and suture of the nerve. Herein, we show that autophagy flux is dysfunctional or blocked in degenerated motoneurons after root avulsion. We also found that there were abnormalities in anterograde/retrograde motor proteins, key secretory pathway factors, and lysosome function. Further, LAMP1 protein was missorted and underglycosylated as well as the proton pump v-ATPase. In vitro modeling revealed how sequential disruptions in these systems likely lead to neurodegeneration. In vivo, we observed that cytoskeletal alterations, induced by a single injection of nocodazole, were sufficient to promote neurodegeneration of avulsed motoneurons. Besides, only pre-treatment with rapamycin, but not post-treatment, neuroprotected after nerve root avulsion. In agreement, overexpressing ATG5 in injured motoneurons led to neuroprotection and attenuation of cytoskeletal and trafficking-related abnormalities. These discoveries serve as proof of concept for autophagy-target therapy to halting the progression of neurodegenerative processes.

How the Adoption of the Big-Data Paradigm Affects the Key Factors That Influence the Effectiveness of an Information Assurance (IA) Framework: A Multiple-Case Study

ERIC Educational Resources Information Center

Apple, Benjamin G.

2017-01-01

This qualitative study identified those factors that influence the perceived effectiveness of traditional IA control frameworks. The key factors examined in this study are risk management, governance, access control, privacy protection, integrity, availability, reliability, and usability. The researcher endeavored to determine how the…

Understanding diagnosis and management of dementia and guideline implementation in general practice: a qualitative study using the theoretical domains framework.

PubMed

Murphy, Kerry; O'Connor, Denise A; Browning, Colette J; French, Simon D; Michie, Susan; Francis, Jill J; Russell, Grant M; Workman, Barbara; Flicker, Leon; Eccles, Martin P; Green, Sally E

2014-03-03

Dementia is a growing problem, causing substantial burden for patients, their families, and society. General practitioners (GPs) play an important role in diagnosing and managing dementia; however, there are gaps between recommended and current practice. The aim of this study was to explore GPs' reported practice in diagnosing and managing dementia and to describe, in theoretical terms, the proposed explanations for practice that was and was not consistent with evidence-based guidelines. Semi-structured interviews were conducted with GPs in Victoria, Australia. The Theoretical Domains Framework (TDF) guided data collection and analysis. Interviews explored the factors hindering and enabling achievement of 13 recommended behaviours. Data were analysed using content and thematic analysis. This paper presents an in-depth description of the factors influencing two behaviours, assessing co-morbid depression using a validated tool, and conducting a formal cognitive assessment using a validated scale. A total of 30 GPs were interviewed. Most GPs reported that they did not assess for co-morbid depression using a validated tool as per recommended guidance. Barriers included the belief that depression can be adequately assessed using general clinical indicators and that validated tools provide little additional information (theoretical domain of 'Beliefs about consequences'); discomfort in using validated tools ('Emotion'), possibly due to limited training and confidence ('Skills'; 'Beliefs about capabilities'); limited awareness of the need for, and forgetting to conduct, a depression assessment ('Knowledge'; 'Memory, attention and decision processes'). Most reported practising in a manner consistent with the recommendation that a formal cognitive assessment using a validated scale be undertaken. Key factors enabling this were having an awareness of the need to conduct a cognitive assessment ('Knowledge'); possessing the necessary skills and confidence ('Skills'; 'Beliefs about capabilities'); and having adequate time and resources ('Environmental context and resources'). This is the first study to our knowledge to use a theoretical approach to investigate the barriers and enablers to guideline-recommended diagnosis and management of dementia in general practice. It has identified key factors likely to explain GPs' uptake of the guidelines. The results have informed the design of an intervention aimed at supporting practice change in line with dementia guidelines, which is currently being evaluated in a cluster randomised trial.

14 CFR 23.337 - Limit maneuvering load factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factors. 23.337... Flight Loads § 23.337 Limit maneuvering load factors. (a) The positive limit maneuvering load factor n... airplanes; or (3) 6.0 for acrobatic category airplanes. (b) The negative limit maneuvering load factor may...

Distinct tissue-specific transcriptional regulation revealed by gene regulatory networks in maize.

PubMed

Huang, Ji; Zheng, Juefei; Yuan, Hui; McGinnis, Karen

2018-06-07

Transcription factors (TFs) are proteins that can bind to DNA sequences and regulate gene expression. Many TFs are master regulators in cells that contribute to tissue-specific and cell-type-specific gene expression patterns in eukaryotes. Maize has been a model organism for over one hundred years, but little is known about its tissue-specific gene regulation through TFs. In this study, we used a network approach to elucidate gene regulatory networks (GRNs) in four tissues (leaf, root, SAM and seed) in maize. We utilized GENIE3, a machine-learning algorithm combined with large quantity of RNA-Seq expression data to construct four tissue-specific GRNs. Unlike some other techniques, this approach is not limited by high-quality Position Weighed Matrix (PWM), and can therefore predict GRNs for over 2000 TFs in maize. Although many TFs were expressed across multiple tissues, a multi-tiered analysis predicted tissue-specific regulatory functions for many transcription factors. Some well-studied TFs emerged within the four tissue-specific GRNs, and the GRN predictions matched expectations based upon published results for many of these examples. Our GRNs were also validated by ChIP-Seq datasets (KN1, FEA4 and O2). Key TFs were identified for each tissue and matched expectations for key regulators in each tissue, including GO enrichment and identity with known regulatory factors for that tissue. We also found functional modules in each network by clustering analysis with the MCL algorithm. By combining publicly available genome-wide expression data and network analysis, we can uncover GRNs at tissue-level resolution in maize. Since ChIP-Seq and PWMs are still limited in several model organisms, our study provides a uniform platform that can be adapted to any species with genome-wide expression data to construct GRNs. We also present a publicly available database, maize tissue-specific GRN (mGRN, https://www.bio.fsu.edu/mcginnislab/mgrn/ ), for easy querying. All source code and data are available at Github ( https://github.com/timedreamer/maize_tissue-specific_GRN ).

Feedback Augmented Sub-Ranging (FASR) Quantizer

NASA Technical Reports Server (NTRS)

Guilligan, Gerard

2012-01-01

This innovation is intended to reduce the size, power, and complexity of pipeline analog-to-digital converters (ADCs) that require high resolution and speed along with low power. Digitizers are important components in any application where analog signals (such as light, sound, temperature, etc.) need to be digitally processed. The innovation implements amplification of a sampled residual voltage in a switched capacitor amplifier stage that does not depend on charge redistribution. The result is less sensitive to capacitor mismatches that cause gain errors, which are the main limitation of such amplifiers in pipeline ADCs. The residual errors due to mismatch are reduced by at least a factor of 16, which is equivalent to at least 4 bits of improvement. The settling time is also faster because of a higher feedback factor. In traditional switched capacitor residue amplifiers, closed-loop amplification of a sampled and held residue signal is achieved by redistributing sampled charge onto a feedback capacitor around a high-gain transconductance amplifier. The residual charge that was sampled during the acquisition or sampling phase is stored on two or more capacitors, often equal in value or integral multiples of each other. During the hold or amplification phase, all of the charge is redistributed onto one capacitor in the feedback loop of the amplifier to produce an amplified voltage. The key error source is the non-ideal ratios of feedback and input capacitors caused by manufacturing tolerances, called mismatches. The mismatches cause non-ideal closed-loop gain, leading to higher differential non-linearity. Traditional solutions to the mismatch errors are to use larger capacitor values (than dictated by thermal noise requirements) and/or complex calibration schemes, both of which increase the die size and power dissipation. The key features of this innovation are (1) the elimination of the need for charge redistribution to achieve an accurate closed-loop gain of two, (2) a higher feedback factor in the amplifier stage giving a higher closed-loop bandwidth compared to the prior art, and (3) reduced requirement for calibration. The accuracy of the new amplifier is mainly limited by the sampling networks parasitic capacitances, which should be minimized in relation to the sampling capacitors.

Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).

PubMed

Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

2014-12-01

In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+Δt) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+Δt, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+Δt, the number of fish stocked per batch is fixed; therefore, extra profit is obtained by increasing either TGC, which increases the annual number of batches, or by decreasing FCR, which decreases annual feed consumption. EVTGC is 0.03 €/kg of fish and EVFCR is 0.05-0.06 €/kg of fish. These results emphasize the importance of calculating economic values in the right context to develop efficient future breeding programs in aquaculture.

Biosurfactant gene clusters in eukaryotes: regulation and biotechnological potential.

PubMed

Roelants, Sophie L K W; De Maeseneire, Sofie L; Ciesielska, Katarzyna; Van Bogaert, Inge N A; Soetaert, Wim

2014-04-01

Biosurfactants (BSs) are a class of secondary metabolites representing a wide variety of structures that can be produced from renewable feedstock by a wide variety of micro-organisms. They have (potential) applications in the medical world, personal care sector, mining processes, food industry, cosmetics, crop protection, pharmaceuticals, bio-remediation, household detergents, paper and pulp industry, textiles, paint industries, etc. Especially glycolipid BSs like sophorolipids (SLs), rhamnolipids (RLs), mannosylerythritol lipids (MELs) and cellobioselipids (CBLs) have been described to provide significant opportunities to (partially) replace chemical surfactants. The major two factors currently limiting the penetration of BSs into the market are firstly the limited structural variety and secondly the rather high production price linked with the productivity. One of the keys to resolve the above mentioned bottlenecks can be found in the genetic engineering of natural producers. This could not only result in more efficient (economical) recombinant producers, but also in a diversification of the spectrum of available BSs as such resolving both limiting factors at once. Unraveling the genetics behind the biosynthesis of these interesting biological compounds is indispensable for the tinkering, fine tuning and rearrangement of these biological pathways with the aim of obtaining higher yields and a more extensive structural variety. Therefore, this review focuses on recent developments in the investigation of the biosynthesis, genetics and regulation of some important members of the family of the eukaryotic glycolipid BSs (MELs, CBLs and SLs). Moreover, recent biotechnological achievements and the industrial potential of engineered strains are discussed.

Influence of Correspondence Noise and Spatial Scaling on the Upper Limit for Spatial Displacement in Fully-Coherent Random-Dot Kinematogram Stimuli

PubMed Central

Tripathy, Srimant P.; Shafiullah, Syed N.; Cox, Michael J.

2012-01-01

Correspondence noise is a major factor limiting direction discrimination performance in random-dot kinematograms [1]. In the current study we investigated the influence of correspondence noise on Dmax, which is the upper limit for the spatial displacement of the dots for which coherent motion is still perceived. Human direction discrimination performance was measured, using 2-frame kinematograms having leftward/rightward motion, over a 200-fold range of dot-densities and a four-fold range of dot displacements. From this data Dmax was estimated for the different dot densities tested. A model was proposed to evaluate the correspondence noise in the stimulus. This model summed the outputs of a set of elementary Reichardt-type local detectors that had receptive fields tiling the stimulus and were tuned to the two directions of motion in the stimulus. A key assumption of the model was that the local detectors would have the radius of their catchment areas scaled with the displacement that they were tuned to detect; the scaling factor k linking the radius to the displacement was the only free parameter in the model and a single value of k was used to fit all of the psychophysical data collected. This minimal, correspondence-noise based model was able to account for 91% of the variability in the human performance across all of the conditions tested. The results highlight the importance of correspondence noise in constraining the largest displacement that can be detected. PMID:23056172

Influence of correspondence noise and spatial scaling on the upper limit for spatial displacement in fully-coherent random-dot kinematogram stimuli.

PubMed

Tripathy, Srimant P; Shafiullah, Syed N; Cox, Michael J

2012-01-01

Correspondence noise is a major factor limiting direction discrimination performance in random-dot kinematograms. In the current study we investigated the influence of correspondence noise on Dmax, which is the upper limit for the spatial displacement of the dots for which coherent motion is still perceived. Human direction discrimination performance was measured, using 2-frame kinematograms having leftward/rightward motion, over a 200-fold range of dot-densities and a four-fold range of dot displacements. From this data Dmax was estimated for the different dot densities tested. A model was proposed to evaluate the correspondence noise in the stimulus. This model summed the outputs of a set of elementary Reichardt-type local detectors that had receptive fields tiling the stimulus and were tuned to the two directions of motion in the stimulus. A key assumption of the model was that the local detectors would have the radius of their catchment areas scaled with the displacement that they were tuned to detect; the scaling factor k linking the radius to the displacement was the only free parameter in the model and a single value of k was used to fit all of the psychophysical data collected. This minimal, correspondence-noise based model was able to account for 91% of the variability in the human performance across all of the conditions tested. The results highlight the importance of correspondence noise in constraining the largest displacement that can be detected.

Fisheries management impacts on target species status

PubMed Central

Melnychuk, Michael C.; Peterson, Emily; Elliott, Matthew; Hilborn, Ray

2017-01-01

Fisheries management systems around the world are highly diverse in their design, operation, and effectiveness at meeting objectives. A variety of management institutions, strategies, and tactics are used across disparate regions, fishing fleets, and taxonomic groups. At a global level, it is unclear which particular management attributes have greatest influence on the status of fished populations, and also unclear which external factors affect the overall success of fisheries management systems. We used expert surveys to characterize the management systems by species of 28 major fishing nations and examined influences of economic, geographic, and fishery-related factors. A Fisheries Management Index, which integrated research, management, enforcement, and socioeconomic attributes, showed wide variation among countries and was strongly affected by per capita gross domestic product (positively) and capacity-enhancing subsidies (negatively). Among 13 management attributes considered, three were particularly influential in whether stock size and fishing mortality are currently in or trending toward desirable states: extensiveness of stock assessments, strength of fishing pressure limits, and comprehensiveness of enforcement programs. These results support arguments that the key to successful fisheries management is the implementation and enforcement of science-based catch or effort limits, and that monetary investment into fisheries can help achieve management objectives if used to limit fishing pressure rather than enhance fishing capacity. Countries with currently less-effective management systems have the greatest potential for improving long-term stock status outcomes and should be the focus of efforts to improve fisheries management globally. PMID:27994155

Fisheries management impacts on target species status.

PubMed

Melnychuk, Michael C; Peterson, Emily; Elliott, Matthew; Hilborn, Ray

2017-01-03

Fisheries management systems around the world are highly diverse in their design, operation, and effectiveness at meeting objectives. A variety of management institutions, strategies, and tactics are used across disparate regions, fishing fleets, and taxonomic groups. At a global level, it is unclear which particular management attributes have greatest influence on the status of fished populations, and also unclear which external factors affect the overall success of fisheries management systems. We used expert surveys to characterize the management systems by species of 28 major fishing nations and examined influences of economic, geographic, and fishery-related factors. A Fisheries Management Index, which integrated research, management, enforcement, and socioeconomic attributes, showed wide variation among countries and was strongly affected by per capita gross domestic product (positively) and capacity-enhancing subsidies (negatively). Among 13 management attributes considered, three were particularly influential in whether stock size and fishing mortality are currently in or trending toward desirable states: extensiveness of stock assessments, strength of fishing pressure limits, and comprehensiveness of enforcement programs. These results support arguments that the key to successful fisheries management is the implementation and enforcement of science-based catch or effort limits, and that monetary investment into fisheries can help achieve management objectives if used to limit fishing pressure rather than enhance fishing capacity. Countries with currently less-effective management systems have the greatest potential for improving long-term stock status outcomes and should be the focus of efforts to improve fisheries management globally.

Long-term mortality risk in individuals with permanent work-related impairment.

PubMed

Scott-Marshall, Heather K; Tompa, Emile; Wang, Ying; Liao, Qing

2014-07-11

Recent estimates indicate that at least one in five activity-limiting injuries occurs at work. Of individuals who suffer these injuries approximately 10% experience some degree of functional impairment. We were interested in investigating long-term mortality risk in individuals with permanent impairment from work injury and to examine whether work disability is a significant explanatory factor. We used a retrospective matched cohort methodology to examine differences in mortality rates between individuals with permanent impairment from a work injury and a group of non-injured controls over a 19-year period. We used a sample of impaired workers to investigate the impact of work disability on mortality risk using percentage of earnings recovery after injury as the key proxy measure. All analyses were stratified by sex. Permanent impairment from a work injury was predictive of premature mortality in both male and female claimants, though the risk was slightly higher among women. Work disability was a key explanatory factor in the rate of death among impaired workers, the effects being more pronounced in men. We also found that higher impairment level was associated with mortality in men but not in women. The study demonstrates the impact of permanent work-related impairment on longevity and identifies work disability as an important determinant of mortality risk. Given the disconnect between impairment ratings derived from standard diagnostic tools and labour-market activity after accident, more research is needed on the specific factors that contribute to work disability, particularly those related to psycho-social health and well-being.

Unique factors rural Veterans' Affairs hospitals face when implementing health care-associated infection prevention initiatives.

PubMed

Harrod, Molly; Manojlovich, Milisa; Kowalski, Christine P; Saint, Sanjay; Krein, Sarah L

2014-01-01

Health care-associated infection (HAI) is costly to hospitals and potentially life-threatening to patients. Numerous infection prevention programs have been implemented in hospitals across the United States. Yet, little is known about infection prevention practices and implementation in rural hospitals. The purpose of this study was to understand the infection prevention practices used by rural Veterans' Affairs (VA) hospitals and the unique factors they face in implementing these practices. This study used a sequential, mixed methods approach. Survey data to identify the HAI prevention practices used by rural VA hospitals were collected, analyzed, and used to inform the development of a semistructured interview guide. Phone interviews were conducted followed by site visits to rural VA hospitals. We found that most rural VA hospitals were using key recommended infection prevention practices. Nonetheless, a number of challenges with practice implementation were identified. The 3 most prominent themes were: (1) lack of human capital including staff with HAI expertise; (2) having to cultivate needed resources; and (3) operating as a system within a system. Rural VA hospitals are providing key infection prevention services to ensure a safe environment for the veterans they serve. However, certain factors, such as staff expertise, limited resources, and local context impacted how and when these practices were used. The creative use of more accessible alternative resources as well as greater flexibility in implementing HAI-related initiatives may be important strategies to further improve delivery of these important services by rural VA hospitals. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Partition of some key regulating services in terrestrial ecosystems: Meta-analysis and review.

PubMed

Viglizzo, E F; Jobbágy, E G; Ricard, M F; Paruelo, J M

2016-08-15

Our knowledge about the functional foundations of ecosystem service (ES) provision is still limited and more research is needed to elucidate key functional mechanisms. Using a simplified eco-hydrological scheme, in this work we analyzed how land-use decisions modify the partition of some essential regulatory ES by altering basic relationships between biomass stocks and water flows. A comprehensive meta-analysis and review was conducted based on global, regional and local data from peer-reviewed publications. We analyzed five datasets comprising 1348 studies and 3948 records on precipitation (PPT), aboveground biomass (AGB), AGB change, evapotranspiration (ET), water yield (WY), WY change, runoff (R) and infiltration (I). The conceptual framework was focused on ES that are associated with the ecological functions (e.g., intermediate ES) of ET, WY, R and I. ES included soil protection, carbon sequestration, local climate regulation, water-flow regulation and water recharge. To address the problem of data normality, the analysis included both parametric and non-parametric regression analysis. Results demonstrate that PPT is a first-order biophysical factor that controls ES release at the broader scales. At decreasing scales, ES are partitioned as result of PPT interactions with other biophysical and anthropogenic factors. At intermediate scales, land-use change interacts with PPT modifying ES partition as it the case of afforestation in dry regions, where ET and climate regulation may be enhanced at the expense of R and water-flow regulation. At smaller scales, site-specific conditions such as topography interact with PPT and AGB displaying different ES partition formats. The probable implications of future land-use and climate change on some key ES production and partition are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

WRKY transcription factors: key components in abscisic acid signalling.

PubMed

Rushton, Deena L; Tripathi, Prateek; Rabara, Roel C; Lin, Jun; Ringler, Patricia; Boken, Ashley K; Langum, Tanner J; Smidt, Lucas; Boomsma, Darius D; Emme, Nicholas J; Chen, Xianfeng; Finer, John J; Shen, Qingxi J; Rushton, Paul J

2012-01-01

WRKY transcription factors (TFs) are key regulators of many plant processes, including the responses to biotic and abiotic stresses, senescence, seed dormancy and seed germination. For over 15 years, limited evidence has been available suggesting that WRKY TFs may play roles in regulating plant responses to the phytohormone abscisic acid (ABA), notably some WRKY TFs are ABA-inducible repressors of seed germination. However, the roles of WRKY TFs in other aspects of ABA signalling, and the mechanisms involved, have remained unclear. Recent significant progress in ABA research has now placed specific WRKY TFs firmly in ABA-responsive signalling pathways, where they act at multiple levels. In Arabidopsis, WRKY TFs appear to act downstream of at least two ABA receptors: the cytoplasmic PYR/PYL/RCAR-protein phosphatase 2C-ABA complex and the chloroplast envelope-located ABAR-ABA complex. In vivo and in vitro promoter-binding studies show that the target genes for WRKY TFs that are involved in ABA signalling include well-known ABA-responsive genes such as ABF2, ABF4, ABI4, ABI5, MYB2, DREB1a, DREB2a and RAB18. Additional well-characterized stress-inducible genes such as RD29A and COR47 are also found in signalling pathways downstream of WRKY TFs. These new insights also reveal that some WRKY TFs are positive regulators of ABA-mediated stomatal closure and hence drought responses. Conversely, many WRKY TFs are negative regulators of seed germination, and controlling seed germination appears a common function of a subset of WRKY TFs in flowering plants. Taken together, these new data demonstrate that WRKY TFs are key nodes in ABA-responsive signalling networks. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Knowledge, attitudes and practices on Schistosomiasis in sub-Saharan Africa: a systematic review.

PubMed

Sacolo, Hlengiwe; Chimbari, Moses; Kalinda, Chester

2018-01-18

Schistosomiasis remains a global health problem with an estimated 250 million people in 78 countries infected, of whom 85% live in Sub-Saharan Africa. Preventive chemotherapy remains the key public health strategy to combat schistosomiasis worldwide. Recently the WHO emphasized on the use of integrative approaches in the control and elimination of schistosomiasis. However, a detailed understanding of sociocultural factors that may influence the uptake of the intended health activities and services is vital. Thus, our study sought to understand the knowledge, attitudes, perceptions, beliefs and practices about schistosomiasis in various communities in Sub-Saharan Africa. A systematic search of literature for the period 2006-2016 was done on Medline, PubMed, CINAHL, Psych info and Google Scholar using the following key words "Schistosomiasis, S. mansoni, S. haematobium, knowledge, attitudes, perceptions, beliefs and practices in Sub-Saharan Africa" in combination with Bolean operators (OR, AND). In this context, we reviewed studies conducted among school children, community members and caregivers of preschool children. Thematic analysis was utilised for the overall synthesis of the selected studies. This was done after reading the articles in depth. Themes were identified and examined for similarities, differences and contradictions. Gaps in schistosomiasis related knowledge and sociocultural barriers towards the uptake of preventive and treatment services among communities in Sub-Saharan Africa were identified. In addition to limited knowledge and negative attitudes, risky water related practices among community members, school children and caregivers of preschool children were identified as key factors promoting transmission of the disease. The study concluded that a comprehensive health education programme using contextual and standardised training tools may improve peoples' knowledge, attitudes and practices in relation to schistosomiasis prevention and control. Findings also highlight the significance of including caregivers in the planning and implementation schistosomiasis control programs targeting pre-school children.

Operational Interventions to Maintenance Error

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.; Walter, Diane; Dulchinos, VIcki

1997-01-01

A significant proportion of aviation accidents and incidents are known to be tied to human error. However, research of flight operational errors has shown that so-called pilot error often involves a variety of human factors issues and not a simple lack of individual technical skills. In aircraft maintenance operations, there is similar concern that maintenance errors which may lead to incidents and accidents are related to a large variety of human factors issues. Although maintenance error data and research are limited, industry initiatives involving human factors training in maintenance have become increasingly accepted as one type of maintenance error intervention. Conscientious efforts have been made in re-inventing the team7 concept for maintenance operations and in tailoring programs to fit the needs of technical opeRAtions. Nevertheless, there remains a dual challenge: 1) to develop human factors interventions which are directly supported by reliable human error data, and 2) to integrate human factors concepts into the procedures and practices of everyday technical tasks. In this paper, we describe several varieties of human factors interventions and focus on two specific alternatives which target problems related to procedures and practices; namely, 1) structured on-the-job training and 2) procedure re-design. We hope to demonstrate that the key to leveraging the impact of these solutions comes from focused interventions; that is, interventions which are derived from a clear understanding of specific maintenance errors, their operational context and human factors components.

Reduction of Maintenance Error Through Focused Interventions

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.; Walter, Diane; Rosekind, Mark R. (Technical Monitor)

1997-01-01

It is well known that a significant proportion of aviation accidents and incidents are tied to human error. In flight operations, research of operational errors has shown that so-called "pilot error" often involves a variety of human factors issues and not a simple lack of individual technical skills. In aircraft maintenance operations, there is similar concern that maintenance errors which may lead to incidents and accidents are related to a large variety of human factors issues. Although maintenance error data and research are limited, industry initiatives involving human factors training in maintenance have become increasingly accepted as one type of maintenance error intervention. Conscientious efforts have been made in re-inventing the "team" concept for maintenance operations and in tailoring programs to fit the needs of technical operations. Nevertheless, there remains a dual challenge: to develop human factors interventions which are directly supported by reliable human error data, and to integrate human factors concepts into the procedures and practices of everyday technical tasks. In this paper, we describe several varieties of human factors interventions and focus on two specific alternatives which target problems related to procedures and practices; namely, 1) structured on-the-job training and 2) procedure re-design. We hope to demonstrate that the key to leveraging the impact of these solutions comes from focused interventions; that is, interventions which are derived from a clear understanding of specific maintenance errors, their operational context and human factors components.

Disarming Fungal Pathogens: Bacillus safensis Inhibits Virulence Factor Production and Biofilm Formation by Cryptococcus neoformans and Candida albicans

PubMed Central

2017-01-01

ABSTRACT Bacteria interact with each other in nature and often compete for limited nutrient and space resources. However, it is largely unknown whether and how bacteria also interact with human fungal pathogens naturally found in the environment. Here, we identified a soil bacterium, Bacillus safensis, which potently blocked several key Cryptococcus neoformans virulence factors, including formation of the antioxidant pigment melanin and production of the antiphagocytic polysaccharide capsule. The bacterium also inhibited de novo cryptococcal biofilm formation but had only modest inhibitory effects on already formed biofilms or planktonic cell growth. The inhibition of fungal melanization was dependent on direct cell contact and live bacteria. B. safensis also had anti-virulence factor activity against another major human-associated fungal pathogen, Candida albicans. Specifically, dual-species interaction studies revealed that the bacterium strongly inhibited C. albicans filamentation and biofilm formation. In particular, B. safensis physically attached to and degraded candidal filaments. Through genetic and phenotypic analyses, we demonstrated that bacterial chitinase activity against fungal cell wall chitin is a factor contributing to the antipathogen effect of B. safensis. PMID:28974618

Eco-bio-social determinants for house infestation by non-domiciliated Triatoma dimidiata in the Yucatan Peninsula, Mexico.

PubMed

Dumonteil, Eric; Nouvellet, Pierre; Rosecrans, Kathryn; Ramirez-Sierra, Maria Jesus; Gamboa-León, Rubi; Cruz-Chan, Vladimir; Rosado-Vallado, Miguel; Gourbière, Sébastien

2013-01-01

Chagas disease is a vector-borne disease of major importance in the Americas. Disease prevention is mostly limited to vector control. Integrated interventions targeting ecological, biological and social determinants of vector-borne diseases are increasingly used for improved control. We investigated key factors associated with transient house infestation by T. dimidiata in rural villages in Yucatan, Mexico, using a mixed modeling approach based on initial null-hypothesis testing followed by multimodel inference and averaging on data from 308 houses from three villages. We found that the presence of dogs, chickens and potential refuges, such as rock piles, in the peridomicile as well as the proximity of houses to vegetation at the periphery of the village and to public light sources are major risk factors for infestation. These factors explain most of the intra-village variations in infestation. These results underline a process of infestation distinct from that of domiciliated triatomines and may be used for risk stratification of houses for both vector surveillance and control. Combined integrated vector interventions, informed by an Ecohealth perspective, should aim at targeting several of these factors to effectively reduce infestation and provide sustainable vector control.

48 CFR 1352.215-75 - Evaluation criteria.

Code of Federal Regulations, 2013 CFR

2013-10-01

... relative importance among the technical evaluation factors.] Based upon the results of the integrated... and manage the contract and the means that will be used to accomplish the contract requirements. The... non-performance. Factor 3—KEY PERSONNEL. The education, experience, and accomplishments of key...

48 CFR 1352.215-75 - Evaluation criteria.

Code of Federal Regulations, 2014 CFR

2014-10-01

... relative importance among the technical evaluation factors.] Based upon the results of the integrated... and manage the contract and the means that will be used to accomplish the contract requirements. The... non-performance. Factor 3—KEY PERSONNEL. The education, experience, and accomplishments of key...

48 CFR 1352.215-75 - Evaluation criteria.

Code of Federal Regulations, 2012 CFR

2012-10-01

... relative importance among the technical evaluation factors.] Based upon the results of the integrated... and manage the contract and the means that will be used to accomplish the contract requirements. The... non-performance. Factor 3—KEY PERSONNEL. The education, experience, and accomplishments of key...

Impact of lowering the legal blood alcohol concentration limit to 0.03 on male, female and teenage drivers involved alcohol-related crashes in Japan.

PubMed

Desapriya, E; Shimizu, S; Pike, I; Subzwari, S; Scime, G

2007-09-01

In June of 2002, a revision to part of the Road Traffic Act drastically increased the penalties for drinking and driving offences in Japan. Most notably, the legal blood alcohol concentration (BAC) limit for driving was lowered from 0.05 mg/ml to 0.03 mg/ml. The rationale for the new lower BAC limit was predicated on the assumption that drinking drivers will comply with the new, lower limit by reducing the amount of alcohol they consume prior to driving, thereby lowering their risk of crash involvement. This, in turn, would lead to fewer alcohol-related crashes. A key limitation of previous lower BAC evaluation research in determining the effectiveness of lower legal BAC limit policies is the assumption of population homogeneity in responding to the laws. The present analysis is unique in this perspective and focuses on the evaluation of the impact of BAC limit reduction on different segments of the population. The chief objective of this research is to quantify the extent to which lowering the legal limit of BAC has reduced male, female and teenager involvement in motor vehicle crashes in Japan since 2002. Most notably, the introduction of reduced BAC limit legislation resulted in a statistically significant decrease in the number of alcohol-impaired drivers on the road in Japan, indicating responsiveness to the legal change among adults and teenagers. In addition, this preliminary assessment appears to indicate that the implementation of 0.03 BAC laws and other associated activities are associated with statistically significant reductions in alcohol-involved motor vehicle crashes. In comparison, the rates of total crashes showed no statistically significant decline nor increase in the period following the introduction of the BAC law, indicating that the lower BAC limit only had an effect on alcohol-related crashes in Japan. The evidence suggests that the lower BAC legal limit and perceived risk of detection are the two most important factors resulting in a sustained change in drinking and driving behaviour in Japan. It is recommended that future research and resources in other countries be focused on these factors as determinants to reduced alcohol-related crashes.

A scoping review of prevalence, incidence and risk factors for HIV infection amongst young people in Brazil.

PubMed

Saffier, Igor Pedrosa; Kawa, Hélia; Harling, Guy

2017-10-11

Despite young people being a key population for HIV prevention, the HIV epidemic amongst young Brazilians is perceived to be growing. We therefore reviewed all published literature on HIV prevalence and risk factors for HIV infection amongst 10-25 year olds in Brazil. We searched Embase, LILACS, Proquest, PsycINFO, PubMed, Scopus and Web of Science for studies published up to March 2017 and analyzed reference lists of relevant studies. We included published studies from any time in the HIV epidemic which provided estimates specific to ages 10-25 (or some subset of this age range) for Brazilians on either: (a) HIV prevalence or incidence; or (b) the association between HIV and socio-demographic or behavioral risk factors. Forty eight publications met the inclusion criteria: 44 cross-sectional, two case-control, two cohort. Four studies analysed national data. Forty seven studies provided HIV prevalence estimates, largely for six population subgroups: Counselling and Testing Center attendees; blood donors; pregnant women; institutional individuals; men-who-have-sex-with-men (MSM) and female sex workers (FSW); four provided HIV incidence estimates. Twelve studies showed HIV status to be associated with a wide range of risk factors, including age, sexual and reproductive history, infection history, substance use, geography, marital status, mental health and socioeconomic status. Few published studies have examined HIV amongst young people in Brazil, and those published have been largely cross-sectional and focused on traditional risk groups and the south of the country. Despite these limitations, the literature shows raised HIV prevalence amongst MSM and FSW, as well as amongst those using drugs. Time trends are harder to identify, although rates appear to be falling for pregnant women, possibly reversing an earlier de-masculinization of the epidemic. Improved surveillance of HIV incidence, prevalence and risk factors is a key component of efforts to eliminate HIV in Brazil.

Tree Mortality following Prescribed Fire and a Storm Surge Event in Slash Pine ( Pinus elliottii var. densa ) Forests in the Florida Keys, USA

DOE PAGES

Sah, Jay P.; Ross, Michael S.; Snyder, James R.; ...

2010-01-01

In fire-dependent forests, managers are interested in predicting the consequences of prescribed burning on postfire tree mortality. We examined the effects of prescribed fire on tree mortality in Florida Keys pine forests, using a factorial design with understory type, season, and year of burn as factors. We also used logistic regression to model the effects of burn season, fire severity, and tree dimensions on individual tree mortality. Despite limited statistical power due to problems in carrying out the full suite of planned experimental burns, associations with tree and fire variables were observed. Post-fire pine tree mortality was negatively correlated withmore » tree size and positively correlated with char height and percent crown scorch. Unlike post-fire mortality, tree mortality associated with storm surge from Hurricane Wilma was greater in the large size classes. Due to their influence on population structure and fuel dynamics, the size-selective mortality patterns following fire and storm surge have practical importance for using fire as a management tool in Florida Keys pinelands in the future, particularly when the threats to their continued existence from tropical storms and sea level rise are expected to increase.« less

Redesigning a Ministry of Health's organizational structure: exploring implementation challenges through Botswana's experiences.

PubMed

Seitio-Kgokgwe, Onalenna; Gauld, Robin D C; Hill, Philip C; Barnett, Pauline

2016-04-01

The Botswana's Ministry of Health redesigned and adopted a new organizational structure in 2005, which was poorly implemented. This article explores factors that influenced the implementation of this organizational structure. This article draws from data collected through in-depth interviews with 54 purposively selected key informants comprising policy makers, senior managers and staff of the Ministry of Health (N = 40) and senior officers from various stakeholder organizations (N = 14). Participants generally felt that the review of the Ministry of Health organizational structure was important. The previous structure was considered obsolete with fragmented functions that limited the overall performance of the health system. The new organizational structure was viewed to be aligned to current national priorities with potential to positively influence performance. Some key weaknesses identified included lack of consultation and information sharing with workers during the restructuring process, which affected the understanding of their new roles, failure to mobilize key resources to support implementation of the new structure and inadequate monitoring of the implementation process. Redesigning an organizational structure is a major change. There is a need for effective and sustained leadership to plan, direct, coordinate, monitor and evaluate the implementation phase of the reform. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

[Analysis on barriers of urban sustainable development based on DEMATEL: a case of Shenyang City].

PubMed

Li, Chun-Rong; Geng, Yong; Xue, Bing; Ren, Wan-Xia; Dong, Hui-Juan

2012-10-01

To scientifically identify the key barriers which the urban sustainable development is facing and to analyze the interrelationships among the barriers are of significance to promote urban sustainable development. Through literature review, site investigation and structural interview, 21 factors affecting the Shenyang City's sustainable development were recognized, and based on questionnaire survey and statistics analysis, 12 main factors were screened. Further, by employing decision-making and trial evaluation laboratory (DEMATEL) method, the interrelationships among these factors were analyzed. The key factors affecting the Shenyang's sustainable development included the lack of leaders' attention, the economy-oriented governmental performance evaluation system, the lower public awareness on sustainable development, and the lack of academic understanding on regional eco-carrying capacity and related key projects. It was suggested that the local government should pay more attention on sustainable development, increase propaganda activities, reform governmental performance evaluation system, establish a reward-punishment system for promoting sustainable development and an effective monitoring mechanism, and enhance the implementation of related regulations, the local enterprises should establish research and development funds to support the researches of key technologies and introduce key projects, and general publics should improve their awareness on sustainable development and actively participate in related activities.

Public Understanding of Medical Countermeasures.

PubMed

Liu, Brooke Fisher; Quinn, Sandra C; Egnoto, Michael; Freimuth, Vicki; Boonchaisri, Natalie

Medical countermeasures, including new drugs and vaccines, are necessary to protect the public's health from novel diseases and terrorist threats. Experience with the 2001 anthrax attack and the 2009 H1N1 pandemic suggest that there is limited willingness to accept such drugs and that minority groups may respond differently from others. We conducted 148 intercept interviews in the metropolitan Washington, DC, area, examining 2 hypothetical scenarios: a new respiratory virus and public exposure to high levels of radiation. Findings provide insights into key factors that affect whether diverse members of the public comply with recommended protective actions like taking emergency authorized vaccines. These insights can help improve how public health practitioners communicate during uncertain times.

A model of sexually and physically victimized women's process of attaining effective formal help over time: the role of social location, context, and intervention.

PubMed

Kennedy, Angie C; Adams, Adrienne; Bybee, Deborah; Campbell, Rebecca; Kubiak, Sheryl Pimlott; Sullivan, Cris

2012-09-01

As empirical evidence has demonstrated the pervasiveness of sexual assault and intimate partner violence in the lives of women, and the links to poor mental health outcomes, attention has turned to examining how women seek and access formal help. We present a conceptual model that addresses prior limitations and makes three key contributions: It foregrounds the influence of social location and multiple contextual factors; emphasizes the importance of the attainment of effective formal help that meets women's needs and leads to positive mental health outcomes; and highlights the role of interventions in facilitating help attainment. We conclude with research and practice implications.

Research on distributed heterogeneous data PCA algorithm based on cloud platform

NASA Astrophysics Data System (ADS)

Zhang, Jin; Huang, Gang

2018-05-01

Principal component analysis (PCA) of heterogeneous data sets can solve the problem that centralized data scalability is limited. In order to reduce the generation of intermediate data and error components of distributed heterogeneous data sets, a principal component analysis algorithm based on heterogeneous data sets under cloud platform is proposed. The algorithm performs eigenvalue processing by using Householder tridiagonalization and QR factorization to calculate the error component of the heterogeneous database associated with the public key to obtain the intermediate data set and the lost information. Experiments on distributed DBM heterogeneous datasets show that the model method has the feasibility and reliability in terms of execution time and accuracy.

Intracellular transport and compartmentation of phosphate in plants.

PubMed

Versaw, Wayne K; Garcia, L Rene

2017-10-01

Phosphate (Pi) is an essential macronutrient with structural and metabolic roles within every compartment of the plant cell. Intracellular Pi transporters direct Pi to each organelle and also control its exchange between subcellular compartments thereby providing the means to coordinate compartmented metabolic processes, including glycolysis, photosynthesis, and respiration. In this review we summarize recent advances in the identification and functional analysis of Pi transporters that localize to vacuoles, chloroplasts, non-photosynthetic plastids, mitochondria, and the Golgi apparatus. Electrical potentials across intracellular membranes and the pH of subcellular environments will also be highlighted as key factors influencing the energetics of Pi transport, and therefore pose limits for Pi compartmentation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exploring the Powerful Ionised Wind in the Seyfert Galaxy PG1211+143

NASA Astrophysics Data System (ADS)

Pounds, Ken

2013-10-01

Highly-ionised high-speed winds in AGN (UFOs) were first detected with XMM-Newton a decade ago, and are now established as a key factor in the study of SMBH accretion, and in the growth and metal enrichment of their host galaxies. However, information on the ionisation and dynamical structure, and the ultimate fate of UFOs remains very limited. We request a 600ks extended XMM-Newton study of the prototype UFO PG1211+143 in AO-13, to obtain high quality EPIC and RGS spectra, to map the flow structure and variability, while seeking evidence for the anticipated interaction with the ISM and possible conversion of the energetic wind to a momentum-driven flow.

Framing global health: the governance challenge.

PubMed

McInnes, Colin; Kamradt-Scott, Adam; Lee, Kelley; Reubi, David; Roemer-Mahler, Anne; Rushton, Simon; Williams, Owain David; Woodling, Marie

2012-01-01

With the emergence of global health comes governance challenges which are equally global in nature. This article identifies some of the initial limitations in analyses of global health governance (GHG) before discussing the focus of this special supplement: the framing of global health issues and the manner in which this impacts upon GHG. Whilst not denying the importance of material factors (such as resources and institutional competencies), the article identifies how issues can be framed in different ways, thereby creating particular pathways of response which in turn affect the potential for and nature of GHG. It also identifies and discusses the key frames operating in global health: evidence-based medicine, human rights, security, economics and development.

Organizational issues related to satisfaction with food and food service in the nursing home from the resident's perspective.

PubMed

Shultz, Jill Armstrong; Crogan, Neva L; Evans, Bronwynne C

2005-01-01

This paper reviews organizational factors that potentially affect food quality and food service in the nursing home. A model is proposed for assessing the influence of organizational technology on resident satisfaction with food and food service from the resident's perspective. Findings from an exploratory phenomenological case study applying the model are presented. Staff knowledge of how to prepare and serve food properly, and staff availability to serve food on time, were key constructs. Resident-staff interactions appeared to moderate resident control over food and food service. Recommendations are suggested for improved communication between residents and staff to address certain limitations and enhance empowerment of residents.

Reliability optimization design of the gear modification coefficient based on the meshing stiffness

NASA Astrophysics Data System (ADS)

Wang, Qianqian; Wang, Hui

2018-04-01

Since the time varying meshing stiffness of gear system is the key factor affecting gear vibration, it is important to design the meshing stiffness to reduce vibration. Based on the effect of gear modification coefficient on the meshing stiffness, considering the random parameters, reliability optimization design of the gear modification is researched. The dimension reduction and point estimation method is used to estimate the moment of the limit state function, and the reliability is obtained by the forth moment method. The cooperation of the dynamic amplitude results before and after optimization indicates that the research is useful for the reduction of vibration and noise and the improvement of the reliability.

What are the elements of the tobacco endgame?

PubMed

Thomson, George; Edwards, Richard; Wilson, Nick; Blakely, Tony

2012-03-01

The available literature on tobacco endgames tends to be limited to discussing means, targets and difficulties. This article offers additional ideas on the key elements of endgame strategies and the circumstances in which these are likely to be adopted and implemented. We suggest such strategies will include explicit plans, will define the nature of `the end of tobacco use/sale' and have target dates within 20 years. The likely circumstances for endgame strategy development include low (probably under 15% adult smoking) prevalence and/or rapid prevalence reductions, wide support and strong political leadership. Even with some or all these circumstances, opposition from business, internal government forces and international factors may influence results.

Public Understanding of Medical Countermeasures

PubMed Central

Quinn, Sandra C.; Egnoto, Michael; Freimuth, Vicki; Boonchaisri, Natalie

2017-01-01

Medical countermeasures, including new drugs and vaccines, are necessary to protect the public's health from novel diseases and terrorist threats. Experience with the 2001 anthrax attack and the 2009 H1N1 pandemic suggest that there is limited willingness to accept such drugs and that minority groups may respond differently from others. We conducted 148 intercept interviews in the metropolitan Washington, DC, area, examining 2 hypothetical scenarios: a new respiratory virus and public exposure to high levels of radiation. Findings provide insights into key factors that affect whether diverse members of the public comply with recommended protective actions like taking emergency authorized vaccines. These insights can help improve how public health practitioners communicate during uncertain times. PMID:28388223

Land crabs as key drivers in tropical coastal forest recruitment

USGS Publications Warehouse

Lindquist, E.S.; Krauss, K.W.; Green, P.T.; O'Dowd, D. J.; Sherman, P.M.; Smith, T. J.

2009-01-01

Plant populations are regulated by a diverse assortment of abiotic and biotic factors that influence seed dispersal and viability, and seedling establishment and growth at the microsite. Rarely does one animal guild exert as significant an influence on different plant assemblages as land crabs. We review three tropical coastal ecosystems-mangroves, island maritime forests, and mainland coastal terrestrial forests-where land crabs directly influence forest composition by limiting tree establishment and recruitment. Land crabs differentially prey on seeds, propagules and seedlings along nutrient, chemical and physical environmental gradients. In all of these ecosystems, but especially mangroves, abiotic gradients are well studied, strong and influence plant species distributions. However, we suggest that crab predation has primacy over many of these environmental factors by acting as the first limiting factor of tropical tree recruitment to drive the potential structural and compositional organisation of coastal forests. We show that the influence of crabs varies relative to tidal gradient, shoreline distance, canopy position, time, season, tree species and fruiting periodicity. Crabs also facilitate forest growth and development through such activities as excavation of burrows, creation of soil mounds, aeration of soils, removal of leaf litter into burrows and creation of carbon-rich soil microhabitats. For all three systems, land crabs influence the distribution, density and size-class structure of tree populations. Indeed, crabs are among the major drivers of tree recruitment in tropical coastal forest ecosystems, and their conservation should be included in management plans of these forests. ?? 2009 Cambridge Philosophical Society.

Expression of a grape (Vitis vinifera) bZIP transcription factor, VlbZIP36, in Arabidopsis thaliana confers tolerance of drought stress during seed germination and seedling establishment.

PubMed

Tu, Mingxing; Wang, Xianhang; Feng, Tongying; Sun, Xiaomeng; Wang, Yaqiong; Huang, Li; Gao, Min; Wang, Yuejin; Wang, Xiping

2016-11-01

Drought is one of the most serious factors that limit agricultural productivity and there is considerable interest in understanding the molecular bases of drought responses and their regulation. While numbers of basic leucine zipper (bZIP) transcription factors (TFs) are known to play key roles in response of plants to various abiotic stresses, only a few group K bZIP TFs have been functionally characterized in the context of stress signaling. In this study, we characterized the expression of the grape (Vitis vinifera) group K bZIP gene, VlbZIP36, and found evidence for its involvement in response to drought and the stress-associated phytohormone abscisic acid (ABA). Transgenic Arabidopsis thaliana lines over-expressing VlbZIP36 under the control of a constitutive promoter showed enhanced dehydration tolerance during the seed germination stage, as well as in the seedling and mature plant stages. The results indicated that VlbZIP36 plays a role in drought tolerance by improving the water status, through limiting water loss, and mitigating cellular damage. The latter was evidenced by reduced cell death, lower electrolyte leakage in the transgenic plants, as well as by increased activities of antioxidant enzymes. We concluded that VlbZIP36 enhances drought tolerance through the transcriptional regulation of ABA-/stress-related genes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Vascular structural and functional changes: their association with causality in hypertension: models, remodeling and relevance.

PubMed

Lee, Robert Mkw; Dickhout, Jeffrey G; Sandow, Shaun L

2017-04-01

Essential hypertension is a complex multifactorial disease process that involves the interaction of multiple genes at various loci throughout the genome, and the influence of environmental factors such as diet and lifestyle, to ultimately determine long-term arterial pressure. These factors converge with physiological signaling pathways to regulate the set-point of long-term blood pressure. In hypertension, structural changes in arteries occur and show differences within and between vascular beds, between species, models and sexes. Such changes can also reflect the development of hypertension, and the levels of circulating humoral and vasoactive compounds. The role of perivascular adipose tissue in the modulation of vascular structure under various disease states such as hypertension, obesity and metabolic syndrome is an emerging area of research, and is likely to contribute to the heterogeneity described in this review. Diversity in structure and related function is the norm, with morphological changes being causative in some beds and states, and in others, a consequence of hypertension. Specific animal models of hypertension have advantages and limitations, each with factors influencing the relevance of the model to the human hypertensive state/s. However, understanding the fundamental properties of artery function and how these relate to signalling mechanisms in real (intact) tissues is key for translating isolated cell and model data to have an impact and relevance in human disease etiology. Indeed, the ultimate aim of developing new treatments to correct vascular dysfunction requires understanding and recognition of the limitations of the methodologies used.

The Potential for Low-Temperature Abiotic Hydrogen Generation and a Hydrogen-Driven Deep Biosphere

PubMed Central

Huang, Shanshan; Thorseth, Ingunn H.

2011-01-01

Abstract The release and oxidation of ferrous iron during aqueous alteration of the mineral olivine is known to reduce aqueous solutions to such extent that molecular hydrogen, H2, forms. H2 is an efficient energy carrier and is considered basal to the deep subsurface biosphere. Knowledge of the potential for H2 generation is therefore vital to understanding the deep biosphere on Earth and on extraterrestrial bodies. Here, we provide a review of factors that may reduce the potential for H2 generation with a focus on systems in the core temperature region for thermophilic to hyperthermophilic microbial life. We show that aqueous sulfate may inhibit the formation of H2, whereas redox-sensitive compounds of carbon and nitrogen are unlikely to have significant effect at low temperatures. In addition, we suggest that the rate of H2 generation is proportional to the dissolution rate of olivine and, hence, limited by factors such as reactive surface areas and the access of water to fresh surfaces. We furthermore suggest that the availability of water and pore/fracture space are the most important factors that limit the generation of H2. Our study implies that, because of large heat flows, abundant olivine-bearing rocks, large thermodynamic gradients, and reduced atmospheres, young Earth and Mars probably offered abundant systems where microbial life could possibly have emerged. Key Words: Serpentinization—Olivine—Hydrogen—Deep biosphere—Water—Mars. Astrobiology 11, 711–724. PMID:21923409

A Review: Proteomics in Retinal Artery Occlusion, Retinal Vein Occlusion, Diabetic Retinopathy and Acquired Macular Disorders.

PubMed

Cehofski, Lasse Jørgensen; Honoré, Bent; Vorum, Henrik

2017-04-28

Retinal artery occlusion (RAO), retinal vein occlusion (RVO), diabetic retinopathy (DR) and age-related macular degeneration (AMD) are frequent ocular diseases with potentially sight-threatening outcomes. In the present review we discuss major findings of proteomic studies of RAO, RVO, DR and AMD, including an overview of ocular proteome changes associated with anti-vascular endothelial growth factor (VEGF) treatments. Despite the severe outcomes of RAO, the proteome of the disease remains largely unstudied. There is also limited knowledge about the proteome of RVO, but proteomic studies suggest that RVO is associated with remodeling of the extracellular matrix and adhesion processes. Proteomic studies of DR have resulted in the identification of potential therapeutic targets such as carbonic anhydrase-I. Proliferative diabetic retinopathy is the most intensively studied stage of DR. Proteomic studies have established VEGF, pigment epithelium-derived factor (PEDF) and complement components as key factors associated with AMD. The aim of this review is to highlight the major milestones in proteomics in RAO, RVO, DR and AMD. Through large-scale protein analyses, proteomics is bringing new important insights into these complex pathological conditions.

The pre-rRNA processing factor DEF is rate limiting for the pathogenesis of MYCN-driven neuroblastoma.

PubMed

Tao, T; Sondalle, S B; Shi, H; Zhu, S; Perez-Atayde, A R; Peng, J; Baserga, S J; Look, A T

2017-07-06

The nucleolar factor, digestive organ expansion factor (DEF), has a key role in ribosome biogenesis, functioning in pre-ribosomal RNA (pre-rRNA) processing as a component of the small ribosomal subunit (SSU) processome. Here we show that the peripheral sympathetic nervous system (PSNS) is very underdeveloped in def-deficient zebrafish, and that def haploinsufficiency significantly decreases disease penetrance and tumor growth rate in a MYCN-driven transgenic zebrafish model of neuroblastoma that arises in the PSNS. Consistent with these findings, DEF is highly expressed in human neuroblastoma, and its depletion in human neuroblastoma cell lines induces apoptosis. Interestingly, overexpression of MYCN in zebrafish and in human neuroblastoma cells results in the appearance of intermediate pre-rRNAs species that reflect the processing of pre-rRNAs through Pathway 2, a pathway that processes pre-rRNAs in a different temporal order than the more often used Pathway 1. Our results indicate that DEF and possibly other components of the SSU processome provide a novel site of vulnerability in neuroblastoma cells that could be exploited for targeted therapy.

Influencing factors on compliance of timely visits among patients with proliferative diabetic retinopathy in southern China: a qualitative study.

PubMed

Duan, Fang; Liu, Yuhong; Chen, Xiang; Congdon, Nathan; Zhang, Jian; Chen, Qianyun; Chen, Lingling; Chen, Xi; Zhang, Xiulan; Yu, Chengpu; Liu, Yizhi

2017-03-27

To identify the reasons for low adherence among patients with diabetic retinopathy (DR) in southern China using a qualitative method. Exploratory indepth interviews were conducted in 27 diabetic patients with proliferative diabetic retinopathy who required vitrectomy surgery at Zhongshan Ophthalmic Centre, Sun Yat-sen University, from March to August 2015. Qualitative data analysis and research software (ATLAS.ti7) was used for data processing and analysis. Factors influencing the occurrence of timely visits included lack of DR related knowledge, fear and worries about insulin, interactions between patients and society combined with the complexity of emotions and social culture, and the economic burden of treatment. Although the reasons for low adherence involved social, emotional, cultural and economic factors, the key issue was the lack of awareness and knowledge of DR. Our findings have several practical implications for health policymakers and programme planners in China. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Exercise rescues obese mothers' insulin sensitivity, placental hypoxia and male offspring insulin sensitivity.

PubMed

Fernandez-Twinn, Denise S; Gascoin, Geraldine; Musial, Barbara; Carr, Sarah; Duque-Guimaraes, Daniella; Blackmore, Heather L; Alfaradhi, Maria Z; Loche, Elena; Sferruzzi-Perri, Amanda N; Fowden, Abigail L; Ozanne, Susan E

2017-03-14

The prevalence of obesity during pregnancy continues to increase at alarming rates. This is concerning as in addition to immediate impacts on maternal wellbeing, obesity during pregnancy has detrimental effects on the long-term health of the offspring through non-genetic mechanisms. A major knowledge gap limiting our capacity to develop intervention strategies is the lack of understanding of the factors in the obese mother that mediate these epigenetic effects on the offspring. We used a mouse model of maternal-diet induced obesity to define predictive correlations between maternal factors and offspring insulin resistance. Maternal hyperinsulinemia (independent of maternal body weight and composition) strongly associated with offspring insulin resistance. To test causality, we implemented an exercise intervention that improved maternal insulin sensitivity without changing maternal body weight or composition. This maternal intervention prevented excess placental lipid deposition and hypoxia (independent of sex) and insulin resistance in male offspring. We conclude that hyperinsulinemia is a key programming factor and therefore an important interventional target during obese pregnancy, and propose moderate exercise as a promising strategy to improve metabolic outcome in both the obese mother and her offspring.

Electrospun silk fibroin/poly (L-lactide-ε-caplacton) graft with platelet-rich growth factor for inducing smooth muscle cell growth and infiltration

PubMed Central

Yin, Anlin; Bowlin, Gary L.; Luo, Rifang; Zhang, Xingdong; Wang, Yunbing; Mo, Xiumei

2016-01-01

The construction of a smooth muscle layer for blood vessel through electrospinning method plays a key role in vascular tissue engineering. However, smooth muscle cells (SMCs) penetration into the electrospun graft to form a smooth muscle layer is limited due to the dense packing of fibers and lack of inducing factors. In this paper, silk fibroin/poly (L-lactide-ε-caplacton) (SF/PLLA-CL) vascular graft loaded with platelet-rich growth factor (PRGF) was fabricated by electrospinning. The in vitro results showed that SMCs cultured in the graft grew fast, and the incorporation of PRGF could induce deeper SMCs infiltrating compared to the SF/PLLA-CL graft alone. Mechanical properties measurement showed that PRGF-incorporated graft had proper tensile stress, suture retention strength, burst pressure and compliance which could match the demand of native blood vessel. The success in the fabrication of PRGF-incorporated SF/PLLA-CL graft to induce fast SMCs growth and their strong penetration into graft has important application for tissue-engineered blood vessels. PMID:27482466

Electrospun silk fibroin/poly (L-lactide-ε-caplacton) graft with platelet-rich growth factor for inducing smooth muscle cell growth and infiltration.

PubMed

Yin, Anlin; Bowlin, Gary L; Luo, Rifang; Zhang, Xingdong; Wang, Yunbing; Mo, Xiumei

2016-12-01

The construction of a smooth muscle layer for blood vessel through electrospinning method plays a key role in vascular tissue engineering. However, smooth muscle cells (SMCs) penetration into the electrospun graft to form a smooth muscle layer is limited due to the dense packing of fibers and lack of inducing factors. In this paper, silk fibroin/poly (L-lactide-ε-caplacton) (SF/PLLA-CL) vascular graft loaded with platelet-rich growth factor (PRGF) was fabricated by electrospinning. The in vitro results showed that SMCs cultured in the graft grew fast, and the incorporation of PRGF could induce deeper SMCs infiltrating compared to the SF/PLLA-CL graft alone. Mechanical properties measurement showed that PRGF-incorporated graft had proper tensile stress, suture retention strength, burst pressure and compliance which could match the demand of native blood vessel. The success in the fabrication of PRGF-incorporated SF/PLLA-CL graft to induce fast SMCs growth and their strong penetration into graft has important application for tissue-engineered blood vessels.

Electrically-controlled near-field radiative thermal modulator made of graphene-coated silicon carbide plates

NASA Astrophysics Data System (ADS)

Yang, Yue; Wang, Liping

2017-08-01

In this work, we propose a hybrid near-field radiative thermal modulator made of two graphene-covered silicon carbide (SiC) plates separated by a nanometer vacuum gap. The near-field photon tunneling between the emitter and receiver is modulated by changing graphene chemical potentials with symmetrically or asymmetrically applied voltage biases. The radiative heat flux calculated from fluctuational electrodynamics significantly varies with graphene chemical potentials due to tunable near-field coupling strength between graphene plasmons across the vacuum gap. Thermal modulation and switching, which are the key functionalities required for a thermal modulator, are theoretically realized and analyzed. Newly introduced quantities of the modulation factor, the sensitivity factor and switching factor are studied quite extensively in a large parameter range for both graphene chemical potential and vacuum gap distance. This opto-electronic device with faster operating mode, which is in principle only limited by electronics and not by the thermal inertia, will facilitate the practical application of active thermal management, thermal circuits, and thermal computing with photon-based near-field thermal transport.

A comparison of the role of beamwidth in biological and engineered sonar.

PubMed

Todd, Bryan D; Müller, Rolf

2017-12-28

Sonar is an important sensory modality for engineers as well as in nature. In engineering, sonar is the dominating modality for underwater sensing. In nature, biosonar is likely to have been a central factor behind the unprecedented evolutionary success of bats, a highly diverse group that accounts for over 20% of all mammal species. However, it remains unclear to what extent engineered and biosonar follow similar design and operational principles. In the current work, the key sonar design characteristic of beamwidth is examined in technical and biosonar. To this end, beamwidth data has been obtained for 23 engineered sonar systems and from numerical beampattern predictions for 151 emission and reception elements (noseleaves and ears) representing bat biosonar. Beamwidth data from these sources is compared to the beamwidth of a planar ellipsoidal transducer as a reference. The results show that engineered and biological both obey the basic physical limit on beamwidth as a function of the ratio of aperture size and wavelength. However, beyond that, the beamwidth data revealed very different behaviors between the engineered and the biological sonar systems. Whereas the beamwidths of the technical sonar systems were very close to the planar transducer limit, the biological samples showed a very wide scatter away from this limit. This scatter was as large, if not wider, than what was seen in a small reference data set obtained with random aluminum cones. A possible interpretation of these differences in the variability could be that whereas sonar engineers try to minimize beamwidth subject to constraints on device size, the evolutionary optimization of bat biosonar beampatterns has been directed at other factors that have left beamwidth as a byproduct. Alternatively, the biosonar systems may require beamwidth values that are larger than the physical limit and differ between species and their sensory ecological niches.

Soil Moisture (SMAP) and Vapor Pressure Deficit Controls on Evaporative Fraction over the Continental U.S.

NASA Astrophysics Data System (ADS)

Salvucci, G.; Rigden, A. J.; Gianotti, D.; Entekhabi, D.

2017-12-01

We analyze the control over evapotranspiration (ET) imposed by soil moisture limitations and stomatal closure due to vapor pressure deficit (VPD) across the United States using estimates of satellite-derived soil moisture from SMAP and a meteorological, data-driven ET estimate over a two year period at over 1000 locations. The ET data are developed independent of soil moisture using the emergent relationship between the diurnal cycle of the relative humidity profile and ET based on ETRHEQ (Salvucci and Gentine (2013), PNAS, 110(16): 6287-6291, Rigden and Salvucci, 2015, WRR, 51(4): 2951-2973; Rigden and Salvucci, 2017, GCB, 23(3) 1140-1151). The key advantage of using this approach to estimate ET is that no measurements of surface limiting factors (soil moisture, leaf area, canopy conductance) are required; instead, ET is estimated from only meteorological data. The combination of these two independent datasets allows for a unique spatial analysis of the control on ET imposed by the availability of soil moisture vs. VPD. Spatial patterns of limitations are inferred by fitting the ETRHEQ-inferred surface conductance to a weighted sum of a Jarvis type stomatal conductance model and bare soil evaporation conductance model, with separate moisture-dependent evaporation efficiency relations for bare soil and vegetation. Spatial patterns are visualized by mapping the optimal curve fitting coefficients and by conducting sensitivity analyses of the resulting fitted model across the Unites States. Results indicate regional variations in rate-limiting factors, and suggest that in some areas the VPD effect on stomatal closure is strong enough to induce a decrease in ET under projected climate change, despite an increase in atmospheric drying (and thus evaporative demand).

Feedback-Assisted Extension of the Tokamak Operating Space to Low Safety Factor

NASA Astrophysics Data System (ADS)

Hanson, J. M.

2013-10-01

Recent DIII-D experiments have demonstrated stable operation at very low edge safety factor, q95 <~ 2 through the use of magnetic feedback to control the n = 1 resistive wall mode (RWM) instability. The performance of tokamak fusion devices may benefit from increased plasma current, and thus, decreased q. However, disruptive stability limits are commonly encountered in experiments at qedge ~ 2 (limited plasmas) and q95 ~ 2 (diverted plasmas), limiting exploration of low q regimes. In the recent DIII-D experiments, the impact and control of key disruptive instabilities was studied. Locked n = 1 modes with exponential growth times on the order of the wall eddy current decay timescale τw preceded disruptions at q95 = 2 . The instabilities have a poloidal structure that is consistent with VALEN simulations of the RWM mode structure at q95 = 2 . Applying proportional gain magnetic feedback control of the n = 1 mode resulted in stabilized operation with q95 reaching 1.9, and an extension of the discharge lifetime for > 100τw . Loss of feedback control was accompanied by power supply saturation, followed by a rapidly growing n = 1 mode and disruption. Comparisons of the feedback dynamics with VALEN simulations will be presented. The DIII-D results complement and will be discussed alongside recent RFX-MOD demonstrations of RWM control using magnetic feedback in limited tokamak discharges with qedge < 2. These results call attention to the utility of magnetic feedback in significantly extending the tokamak operational space and potentially opening a new route to economical fusion power production. Supported by the US Department of Energy under DE-FG02-04ER54761 and DE-FC02-04ER54698.

Iron-Regulated Expression of Alginate Production, Mucoid Phenotype, and Biofilm Formation by Pseudomonas aeruginosa

PubMed Central

Wiens, Jacinta R.; Vasil, Adriana I.; Schurr, Michael J.; Vasil, Michael L.

2014-01-01

ABSTRACT Pseudomonas aeruginosa strains of non-cystic fibrosis (non-CF) origin do not produce significant amounts of extracellular alginate and are nonmucoid. In CF, such isolates can become mucoid through mutation of one of the genes (mucA, mucB, mucC, or mucD) that produce regulatory factors that sequester AlgU, required for increased expression of alginate genes. Mutation of the muc genes in the nonmucoid PAO1, PA14, PAKS-1, and Ps388 strains led to increased levels of extracellular alginate and an obvious mucoid phenotype, but only under iron-limiting growth conditions (≤5 µM), not under iron-replete conditions (≥10 µM). In contrast, >50% of P. aeruginosa isolates from chronic CF pulmonary infections expressed increased levels of alginate and mucoidy both under iron-limiting and iron-replete conditions (i.e., iron-constitutive phenotype). No single iron regulatory factor (e.g., Fur, PvdS) was associated with this loss of iron-regulated alginate expression and mucoidy in these CF isolates. However, the loss of only pyoverdine production, or its uptake, abrogated the ability of P. aeruginosa to produce a robust biofilm that represents the Psl-type of biofilm. In contrast, we show that mutation of the pyoverdine and pyochelin biosynthesis genes and the pyoverdine receptor (FpvA) lead to iron-constitutive expression of the key alginate biosynthesis gene, algD, and an explicitly mucoid phenotype in both iron-limiting and iron-replete conditions. These data indicate that alginate production and mucoidy, in contrast to other types of biofilms produced by P. aeruginosa, are substantially enhanced under iron limitation. These results also have compelling implications in relation to the use of iron chelators in the treatment of P. aeruginosa CF infections. PMID:24496793

Parasites of the Giant Panda: A Risk Factor in the Conservation of a Species.

PubMed

Wang, Tao; Xie, Yue; Zheng, Youle; Wang, Chengdong; Li, Desheng; Koehler, Anson V; Gasser, Robin B

2018-01-01

The giant panda, with an estimated population size of 2239 in the world (in 2015), is a global symbol of wildlife conservation that is threatened by habitat loss, poor reproduction and limited resistance to some infectious diseases. Of these factors, some diseases caused by parasites are considered as the foremost threat to its conservation. However, there is surprisingly little published information on the parasites of the giant panda, most of which has been disseminated in the Chinese literature. Herein, we review all peer-reviewed publications (in English or Chinese language) and governmental documents for information on parasites of the giant pandas, with an emphasis on the intestinal nematode Baylisascaris schroederi (McIntosh, 1939) as it dominates published literature. The purpose of this chapter is to: (i) review the parasites recorded in the giant panda and describe what is known about their biology; (ii) discuss key aspects of the pathogenesis, diagnosis, treatment and control of key parasites that are reported to cause clinical problems and (iii) conclude by making some suggestions for future research. This chapter shows that we are only just 'scratching the surface' when it comes to parasites and parasitological research of the giant panda. Clearly, there needs to be a concerted research effort to support the conservation of this iconic species. © 2018 Elsevier Ltd All rights reserved.

Resolving early mesoderm diversification through single-cell expression profiling.

PubMed

Scialdone, Antonio; Tanaka, Yosuke; Jawaid, Wajid; Moignard, Victoria; Wilson, Nicola K; Macaulay, Iain C; Marioni, John C; Göttgens, Berthold

2016-07-14

In mammals, specification of the three major germ layers occurs during gastrulation, when cells ingressing through the primitive streak differentiate into the precursor cells of major organ systems. However, the molecular mechanisms underlying this process remain unclear, as numbers of gastrulating cells are very limited. In the mouse embryo at embryonic day 6.5, cells located at the junction between the extra-embryonic region and the epiblast on the posterior side of the embryo undergo an epithelial-to-mesenchymal transition and ingress through the primitive streak. Subsequently, cells migrate, either surrounding the prospective ectoderm contributing to the embryo proper, or into the extra-embryonic region to form the yolk sac, umbilical cord and placenta. Fate mapping has shown that mature tissues such as blood and heart originate from specific regions of the pre-gastrula epiblast, but the plasticity of cells within the embryo and the function of key cell-type-specific transcription factors remain unclear. Here we analyse 1,205 cells from the epiblast and nascent Flk1(+) mesoderm of gastrulating mouse embryos using single-cell RNA sequencing, representing the first transcriptome-wide in vivo view of early mesoderm formation during mammalian gastrulation. Additionally, using knockout mice, we study the function of Tal1, a key haematopoietic transcription factor, and demonstrate, contrary to previous studies performed using retrospective assays, that Tal1 knockout does not immediately bias precursor cells towards a cardiac fate.

ULK1 Regulates Melanin Levels in MNT-1 Cells Independently of mTORC1

PubMed Central

Tooze, Sharon A.

2013-01-01

Melanosomes are lysosome-related organelles that serve as specialized sites of melanin synthesis and storage in melanocytes. The progression of melanosomes through the different stages of their formation requires trafficking of specific proteins and membrane constituents in a sequential manner, which is likely to deploy ubiquitous cellular machinery along with melanocyte-specific proteins. Recent evidence revealed a connection between melanogenesis and the autophagy machinery, suggesting a novel role for members of the latter in melanocytes. Here we focused on ULK1, a key autophagy protein which is negatively regulated by mTORC1, to assess its potential role in melanogenesis in MNT-1 cells. We found that ULK1 depletion causes an increase in melanin levels, suggesting an inhibitory function for this protein in melanogenesis. Furthermore, this increase was accompanied by increased transcription of MITF (microphthalmia-associated transcription factor) and tyrosinase and by elevated protein levels of tyrosinase, the rate-limiting factor in melanin biogenesis. We also provide evidence to show that ULK1 function in this context is independent of the canonical ULK1 autophagy partners, ATG13 and FIP200. Furthermore we show that regulation of melanogenesis by ULK1 is independent of mTORC1 inhibition. Our data thus provide intriguing insights regarding the involvement of the key regulatory autophagy machinery in melanogenesis. PMID:24066173

The Future of Clinical Education: Using Futuristic Scenarios to Explore Allied Health Deans' Perspectives on Clinical Education.

PubMed

Romig, Barbara D; Tucker, Ann W; Hewitt, Anne M; O'Sullivan Maillet, Julie

2017-01-01

There is limited information and consensus on the future of clinical education. The Delphi technique was selected to identify agreement among Association of Schools of Allied Health Professions' (ASAHP) allied health deans on the future (2018-2023) of allied health (AH) clinical education. Sixty-one AH deans, 54.9% (61 of 111) of the ASAHP membership, expressed opinions about clinical education through a three-round Delphi study. In conjunction with a conceptual model, four futuristic scenarios were used to encourage deans' feedback on the key factors impacting the future of clinical education. The responses to the four scenarios showed ways the external environment influences which activities the deans recommend. The results presented, by individual scenario and in totality, provide relevant and timely information on the importance and transformation of AH clinical education and its future. Futuristic scenarios, in combination with the Delphi technique, generated information where little exists specific to AH deans' perspectives on AH clinical education. The results offer deans opportunities for future strategic improvements. The use of the futuristic scenarios was suitable for guiding deans' responses and reaching agreement on the future of AH clinical education. These contributions reflect the imminent conditions and healthcare environment identified in the various scenarios and provide additional insight on key factors impacting the future for AH clinical education.

Changes in athlete burnout and motivation over a 12-week league tournament.

PubMed

Cresswell, Scott L; Eklund, Robert C

2005-11-01

To date, empirical reports of an association between motivation and athlete burnout have been exclusively based on cross-sectional research. Conclusions regarding the nature of the relationship between motivation and burnout are limited because they do not provide longitudinal information. To examine the relationship between burnout and motivation across a 12-wk league tournament (pretournament, midtournament, and end of tournament). Data were collected on using the Athlete Burnout Questionnaire and Sport Motivation Scale from 102 adult professional male rugby players at three different times during a 12-wk league tournament. Linear mixed modeling was used to explore hypothesized relationships between individual key characteristics of burnout and factors/covariates across time. Within the models, amotivation, the least self-determined type of motivation, had a large positive association with key characteristics of burnout. Self-determined forms of motivation (i.e., intrinsic motivation) exhibited significant negative associations with burnout. Extrinsic motivation, proposed to exist between intrinsic and amotivation on the self-determination continuum, was negatively associated with sport devaluation and reduced accomplishment as well as positively associated with physical and emotional exhaustion. Other factors related to burnout within the analysis included time (pretournament, in tournament, and end of tournament), team membership, number of injuries, years of national domestic league experience, and win/loss history. Overall, the results reflect the burnout experience may vary over time and support the potential utility of a self-determination theory explanation of burnout.

Risk assessment of the diabetic foot and wound.

PubMed

Wu, Stephanie; Armstrong, David G

2005-03-01

Diabetic foot ulcers are among the most common severe complications of diabetes, affecting up to 68 per 1,000 persons with diabetes per year in the United States. Over half of these patients develop an infection and 20% require some form of amputation during the course of their malady. The key risk factors of diabetic foot ulceration include neuropathy, deformity and repetitive stress (trauma). The key factors associated with non healing of diabetic foot wounds (and therefore amputation) include wound depth, presence of infection and presence of ischaemia. This manuscript will discuss these key risk factors and briefly outline steps for simple, evidence-based assessment of risk in this population.

CATE: A Case Study of an Interdisciplinary Student-Led Microgravity Experiment

NASA Astrophysics Data System (ADS)

Colwell, J. E.; Dove, A.; Lane, S. S.; Tiller, C.; Whitaker, A.; Lai, K.; Hoover, B.; Benjamin, S.

2015-12-01

The Collisional Accretion Experiment (CATE) was designed, built, and flown on NASA's C-9 parabolic flight airplane in less than a year by an interdisciplinary team of 6 undergraduate students under the supervision of two faculty. CATE was selected in the initial NASA Undergraduate Student Instrument Project (USIP) solicitation in the Fall of 2013, and the experiment flight campaign was in July 2014. The experiment studied collisions between different particle populations at low velocities (sub-m/s) in a vacuum and microgravity to gain insight into processes in the protoplanetary disk and planetary ring systems. Faculty provided the experiment concept and key experiment design parameters, and the student team developed the detailed hardware design for all components, manufactured and tested hardware, operated the experiment in flight, and analyzed data post-flight. Students also developed and led an active social media campaign and education and public outreach campaign to engage local high school students in the project. The ability to follow an experiment through from conception to flight was a key benefit for undergraduate students whose available time for projects such as this is frequently limited to their junior and senior years. Key factors for success of the program included having an existing laboratory infrastructure and experience in developing flight payloads and an intrinsically simple experiment concept. Students were highly motivated, in part, by their sense of technical and scientific ownership of the project, and this engagement was key to the project's success.

Feasibility of an International Multiple Sclerosis Rehabilitation Data Repository

PubMed Central

Bradford, Elissa Held; Baert, Ilse; Finlayson, Marcia; Feys, Peter

2018-01-01

Abstract Background: Multiple sclerosis (MS) rehabilitation evidence is limited due to methodological factors, which may be addressed by a data repository. We describe the perceived challenges of, motivators for, interest in participating in, and key features of an international MS rehabilitation data repository. Methods: A multimethod sequential investigation was performed with the results of two focus groups, using nominal group technique, and study aims informing the development of an online questionnaire. Percentage agreement and key quotations illustrated questionnaire findings. Subgroup comparisons were made between clinicians and researchers and between participants in North America and Europe. Results: Rehabilitation professionals from 25 countries participated (focus groups: n = 21; questionnaire: n = 166). The top ten challenges (C) and motivators (M) identified by the focus groups were database control/management (C); ethical/legal concerns (C); data quality (C); time, effort, and cost (C); best practice (M); uniformity (C); sustainability (C); deeper analysis (M); collaboration (M); and identifying research needs (M). Percentage agreement with questionnaire statements regarding challenges to, motivators for, interest in, and key features of a successful repository was at least 80%, 85%, 72%, and 83%, respectively, across each group of statements. Questionnaire subgroup analysis revealed a few differences (P < .05), including that clinicians more strongly identified with improving best practice as a motivator. Conclusions: Findings support clinician and researcher interest in and potential for success of an international MS rehabilitation data repository if prioritized challenges and motivators are addressed and key features are included. PMID:29507539

Feasibility of an International Multiple Sclerosis Rehabilitation Data Repository: Perceived Challenges and Motivators for Sharing Data.

PubMed

Bradford, Elissa Held; Baert, Ilse; Finlayson, Marcia; Feys, Peter; Wagner, Joanne

2018-01-01

Multiple sclerosis (MS) rehabilitation evidence is limited due to methodological factors, which may be addressed by a data repository. We describe the perceived challenges of, motivators for, interest in participating in, and key features of an international MS rehabilitation data repository. A multimethod sequential investigation was performed with the results of two focus groups, using nominal group technique, and study aims informing the development of an online questionnaire. Percentage agreement and key quotations illustrated questionnaire findings. Subgroup comparisons were made between clinicians and researchers and between participants in North America and Europe. Rehabilitation professionals from 25 countries participated (focus groups: n = 21; questionnaire: n = 166). The top ten challenges (C) and motivators (M) identified by the focus groups were database control/management (C); ethical/legal concerns (C); data quality (C); time, effort, and cost (C); best practice (M); uniformity (C); sustainability (C); deeper analysis (M); collaboration (M); and identifying research needs (M). Percentage agreement with questionnaire statements regarding challenges to, motivators for, interest in, and key features of a successful repository was at least 80%, 85%, 72%, and 83%, respectively, across each group of statements. Questionnaire subgroup analysis revealed a few differences (P < .05), including that clinicians more strongly identified with improving best practice as a motivator. Findings support clinician and researcher interest in and potential for success of an international MS rehabilitation data repository if prioritized challenges and motivators are addressed and key features are included.

Galvanising the NHS to Adopt Innovation

PubMed Central

Parris, Stuart; Cochrane, Gavin; Marjanovic, Sonja; Ling, Tom; Chataway, Joanna

2016-01-01

Abstract The Department of Health and the Wellcome Trust, in co-operation with NHS England, asked RAND Europe to conduct a limited consultation with key stakeholders about the practicality of measures and incentives proposed as part of the NHS Accelerated Access Review (AAR), which aims to assess the pathways for the development, assessment, and adoption of innovative medicines and medical technology. Through a focused engagement exercise with key healthcare stakeholders this project explored the implications of selected interim AAR propositions and feasibility of implementation for key actors, in primary and secondary care as well as commissioners and academia. Specifically, the project investigated the feasibility of implementation of three specific propositions including: a new earmarked fund to encourage AHSNs and other key innovation actors to re-design systems to embrace innovation; mobilising the influence of clinical system leaders to champion change; and encouraging secondary care organisations to take on “innovation champion” roles linked to financial incentives and a new emphasis on accountable care organisations. Data was collected on the feasibility of the three AAR propositions from a workshop with AHSN CEOs and Commercial Directors and interviews with senior NHS staff in three AHSN regions (South West, University College London Partners, and North East, North Cumbria). The study concludes with reflections on the feasibility of each recommendation and identifies factors expected to facilitate or challenge their implementation, as well as considering the wider cross cutting issues that may influence the adoption and diffusion of innovation in the NHS. PMID:28083436

Functional ecology of aquatic phagotrophic protists - Concepts, limitations, and perspectives.

PubMed

Weisse, Thomas; Anderson, Ruth; Arndt, Hartmut; Calbet, Albert; Hansen, Per Juel; Montagnes, David J S

2016-08-01

Functional ecology is a subdiscipline that aims to enable a mechanistic understanding of patterns and processes from the organismic to the ecosystem level. This paper addresses some main aspects of the process-oriented current knowledge on phagotrophic, i.e. heterotrophic and mixotrophic, protists in aquatic food webs. This is not an exhaustive review; rather, we focus on conceptual issues, in particular on the numerical and functional response of these organisms. We discuss the evolution of concepts and define parameters to evaluate predator-prey dynamics ranging from Lotka-Volterra to the Independent Response Model. Since protists have extremely versatile feeding modes, we explore if there are systematic differences related to their taxonomic affiliation and life strategies. We differentiate between intrinsic factors (nutritional history, acclimatisation) and extrinsic factors (temperature, food, turbulence) affecting feeding, growth, and survival of protist populations. We briefly consider intraspecific variability of some key parameters and constraints inherent in laboratory microcosm experiments. We then upscale the significance of phagotrophic protists in food webs to the ocean level. Finally, we discuss limitations of the mechanistic understanding of protist functional ecology resulting from principal unpredictability of nonlinear dynamics. We conclude by defining open questions and identifying perspectives for future research on functional ecology of aquatic phagotrophic protists. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.