Sample records for critical factor determining

  1. 21 CFR 113.100 - Processing and production records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... critical factors specified in the scheduled process shall also be recorded. In addition, the following... preservation methods wherein critical factors such as water activity are used in conjunction with thermal... critical factors, as well as other critical factors, and results of aw determinations. (7) Other systems...

  2. Determining the Number of Factors in P-Technique Factor Analysis

    ERIC Educational Resources Information Center

    Lo, Lawrence L.; Molenaar, Peter C. M.; Rovine, Michael

    2017-01-01

    Determining the number of factors is a critical first step in exploratory factor analysis. Although various criteria and methods for determining the number of factors have been evaluated in the usual between-subjects R-technique factor analysis, there is still question of how these methods perform in within-subjects P-technique factor analysis. A…

  3. Determination of Slope Safety Factor with Analytical Solution and Searching Critical Slip Surface with Genetic-Traversal Random Method

    PubMed Central

    2014-01-01

    In the current practice, to determine the safety factor of a slope with two-dimensional circular potential failure surface, one of the searching methods for the critical slip surface is Genetic Algorithm (GA), while the method to calculate the slope safety factor is Fellenius' slices method. However GA needs to be validated with more numeric tests, while Fellenius' slices method is just an approximate method like finite element method. This paper proposed a new method to determine the minimum slope safety factor which is the determination of slope safety factor with analytical solution and searching critical slip surface with Genetic-Traversal Random Method. The analytical solution is more accurate than Fellenius' slices method. The Genetic-Traversal Random Method uses random pick to utilize mutation. A computer automatic search program is developed for the Genetic-Traversal Random Method. After comparison with other methods like slope/w software, results indicate that the Genetic-Traversal Random Search Method can give very low safety factor which is about half of the other methods. However the obtained minimum safety factor with Genetic-Traversal Random Search Method is very close to the lower bound solutions of slope safety factor given by the Ansys software. PMID:24782679

  4. Training Select-in Interviewers for Astronaut Selection: A Program Evaluation

    NASA Technical Reports Server (NTRS)

    Hysong, S.; Galarza, L.; Holland, A.; Billica, Roger (Technical Monitor)

    2000-01-01

    Psychological factors critical to the success of short and long-duration missions have been identified in previous research; however, evaluation for such critical factors in astronaut applicants leaves much room for human interpretation. Thus, an evaluator training session was designed to standardize the interpretation of critical factors, as well as the structure of the select-in interview across evaluators. The purpose of this evaluative study was to determine the effectiveness of the evaluator training sessions and their potential impact on evaluator ratings.

  5. Risk analysis of the thermal sterilization process. Analysis of factors affecting the thermal resistance of microorganisms.

    PubMed

    Akterian, S G; Fernandez, P S; Hendrickx, M E; Tobback, P P; Periago, P M; Martinez, A

    1999-03-01

    A risk analysis was applied to experimental heat resistance data. This analysis is an approach for processing experimental thermobacteriological data in order to study the variability of D and z values of target microorganisms depending on the deviations range of environmental factors, to determine the critical factors and to specify their critical tolerance. This analysis is based on sets of sensitivity functions applied to a specific case of experimental data related to the thermoresistance of Clostridium sporogenes and Bacillus stearothermophilus spores. The effect of the following factors was analyzed: the type of target microorganism; nature of the heating substrate; pH, temperature; type of acid employed and NaCl concentration. The type of target microorganism to be inactivated, the nature of the substrate (reference or real food) and the heating temperature were identified as critical factors, determining about 90% of the alteration of the microbiological risk. The effect of the type of acid used for the acidification of products and the concentration of NaCl can be assumed to be negligible factors for the purposes of engineering calculations. The critical non-uniformity in temperature during thermobacteriological studies was set as 0.5% and the critical tolerances of pH value and NaCl concentration were 5%. These results are related to a specific case study, for that reason their direct generalization is not correct.

  6. Factors Affecting Student Retention in Online Courses: Overcoming This Critical Problem

    ERIC Educational Resources Information Center

    Gaytan, Jorge

    2013-01-01

    The purpose of this study was to determine what a panel of 15 experts would identify as critical factors affecting student retention in online courses that will serve as implications for educational leaders to guide their student retention strategies, online organizational structures, institutional policies, and online instructional activities. A…

  7. Critical Success Factors: How One Multinational Company Develops Global E-Learning

    ERIC Educational Resources Information Center

    Nathan, Edward Pavel

    2011-01-01

    This research study examined how a multinational company determined what the critical success factors (CSFs) were for developing global e-learning. The study analyzed how these CSFs were grouped together to make their management more efficient. There were 21 participants in the study who were key stakeholders from the United States, Europe, Latin…

  8. Critical Success Factors: How One Multinational Company Develops Global E-Learning

    ERIC Educational Resources Information Center

    Nathan, Edward Pavel

    2009-01-01

    This research study examined how a multinational company determined what the critical success factors (CSFs) were for developing global e-learning. The study analyzed how these CSFs were grouped together in order to make their management more efficient. There were 21 participants in the study who were key stakeholders and came from one of four…

  9. Critical factors for EIA implementation: literature review and research options.

    PubMed

    Zhang, Jie; Kørnøv, Lone; Christensen, Per

    2013-01-15

    After decades of development, the gap between expectations of Environment Impact Assessments (EIA) and their practical performance remains significant. Research has been done to identify the critical factors for an effective implementation of EIA. However, this research, to a large extent, has not been cumulated and analysed comprehensively according to the stages of the EIA process. This paper contributes to the critical review of the literature on EIA implementation and effectiveness by cumulating mainly empirical findings in an implementation theoretical perspective. It focuses on the links between different critical factors and how they relate to different stages in the EIA and thus influence the decision making process. After reviewing 33 refereed journal articles published between 1999 and 2011, we identified 203 notions of critical factors. Of these, 102 related to different stages defined in our comprehensive EIA implementation model, and 101 were identified as general factors related to the whole EIA system. The number of notions of stage factors and general factors is thus about equal. An overlap between stage factors and general factors was found, which demonstrates that critical factors function differently in different cases. The function of the critical factors is complex and it is difficult to determine contingencies and causations. In the sources we examined, there is evidently an imbalance between in-depth empirical research and general knowledge, and the paper offers some suggestions for future research. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Analysis of driver critical reason and years of driving experience in large truck crashes, analysis brief.

    DOT National Transportation Integrated Search

    2017-01-01

    The 2005 Large Truck Crash Causation Study (LTCCS)i was the first-ever national study to attempt to determine the critical reasons and associated factors that contribute to serious large truck crashes. The LTCCS defines critical reason as the r...

  11. Strain Measurements within Fibre Boards. Part II: Strain Concentrations at the Crack Tip of MDF Specimens Tested by the Wedge Splitting Method

    PubMed Central

    Sinn, Gerhard; Müller, Ulrich; Konnerth, Johannes; Rathke, Jörn

    2012-01-01

    This is the second part of an article series where the mechanical and fracture mechanical properties of medium density fiberboard (MDF) were studied. While the first part of the series focused on internal bond strength and density profiles, this article discusses the fracture mechanical properties of the core layer. Fracture properties were studied with a wedge splitting setup. The critical stress intensity factors as well as the specific fracture energies were determined. Critical stress intensity factors were calculated from maximum splitting force and two-dimensional isotropic finite elements simulations of the specimen geometry. Size and shape of micro crack zone were measured with electronic laser speckle interferometry. The process zone length was approx. 5 mm. The specific fracture energy was determined to be 45.2 ± 14.4 J/m2 and the critical stress intensity factor was 0.11 ± 0.02 MPa.

  12. A quantitative correlational investigation of the definition of key decision variables used for the determination of wind energy systems' feasibility

    NASA Astrophysics Data System (ADS)

    Kelly, Kathleen M.

    Several factors are critical in determining if a wind farm has a high probability of success. These factors include wind energy potential or wind class, sales price, cost of the wind energy generated, market for selling the wind, capacity factor or efficiency of the turbines, capital investment cost, debt and financing, and governmental factors such as taxes and incentives. This research studied the critical factors of thirty-three land based wind farms in the United States with over 20 mega-watts (MW) of capacity that have become operational since 1999. The goal was to develop a simple yet effective decision model using the critical factors to predict an internal rate of return (IRR) and the impact of having a tax credit to supplement the revenue stream. The study found that there are five critical factors that are significantly correlated with the internal rate of return (IRR) of a wind farm project. The critical factors are wind potential or wind class, cost of the wind energy generated, capacity factor or efficiency of the wind turbines, cost of capital investment, and the existence of a federal production tax credit (PTC). The decision model was built using actual wind farm data and industry standards whereby a score from zero to one hundred was coded for each of values except for the production tax credit. Since all the projects qualified for the production tax credit prior to their start up, it was no longer a variable. However, without the presence of this tax credit, the data imply that the projects would not be profitable within the first ten to fifteen years of operation. The scores for each of the categories were totaled and regressed against a calculated internal rate of return. There was ninety-seven percent correlation which was supported by simulation analysis. While this model is not intended to supplant rigorous accounting and financial study, it will help quickly determine if a site has potential and save many hours of analytical work.

  13. Unit Reynolds number, Mach number and pressure gradient effects on laminar-turbulent transition in two-dimensional boundary layers

    NASA Astrophysics Data System (ADS)

    Risius, Steffen; Costantini, Marco; Koch, Stefan; Hein, Stefan; Klein, Christian

    2018-05-01

    The influence of unit Reynolds number (Re_1=17.5× 106-80× 106 {m}^{-1}), Mach number (M= 0.35-0.77) and incompressible shape factor (H_{12} = 2.50-2.66) on laminar-turbulent boundary layer transition was systematically investigated in the Cryogenic Ludwieg-Tube Göttingen (DNW-KRG). For this investigation the existing two-dimensional wind tunnel model, PaLASTra, which offers a quasi-uniform streamwise pressure gradient, was modified to reduce the size of the flow separation region at its trailing edge. The streamwise temperature distribution and the location of laminar-turbulent transition were measured by means of temperature-sensitive paint (TSP) with a higher accuracy than attained in earlier measurements. It was found that for the modified PaLASTra model the transition Reynolds number (Re_{ {tr}}) exhibits a linear dependence on the pressure gradient, characterized by H_{12}. Due to this linear relation it was possible to quantify the so-called `unit Reynolds number effect', which is an increase of Re_{ {tr}} with Re_1. By a systematic variation of M, Re_1 and H_{12} in combination with a spectral analysis of freestream disturbances, a stabilizing effect of compressibility on boundary layer transition, as predicted by linear stability theory, was detected (`Mach number effect'). Furthermore, two expressions were derived which can be used to calculate the transition Reynolds number as a function of the amplitude of total pressure fluctuations, Re_1 and H_{12}. To determine critical N-factors, the measured transition locations were correlated with amplification rates, calculated by incompressible and compressible linear stability theory. By taking into account the spectral level of total pressure fluctuations at the frequency of the most amplified Tollmien-Schlichting wave at transition location, the scatter in the determined critical N-factors was reduced. Furthermore, the receptivity coefficients dependence on incidence angle of acoustic waves was used to correct the determined critical N-factors. Thereby, a found dependency of the determined critical N-factors on H_{12} decreased, leading to an average critical N-factor of about 9.5 with a standard deviation of σ ≈ 0.8.

  14. Critical parameters for sterilization of oil palm fruit by microwave irradiation

    NASA Astrophysics Data System (ADS)

    Sarah, Maya; Taib, M. R.

    2017-08-01

    Study to evaluate critical parameters for microwave irradiation to sterilize oil palm fruit was carried out at power density of 560 to 1120 W/kg. Critical parameters are important to ensure moisture loss during sterilization exceed the critical moisture (Mc) but less than maximum moisture (Mmax). Critical moisture in this study was determined according to dielectric loss factor of heated oil palm fruits at 2450 MHz. It was obtained from slope characterization of dielectric loss factor-vs-moisture loss curve. The Mc was used to indicate critical temperature (Tc) and critical time (tc) for microwave sterilization. To ensure moisture loss above critical value but not exceed maximum value, the combinations of time-temperature for sterilization of oil palm fruits by microwave irradiation were 6 min and 75°C to 17 min and 82°C respectively.

  15. An arthroscopic evaluation of the anatomical "critical zone".

    PubMed

    Naidoo, N; Lazarus, L; Osman, S A; Satyapal, K S

    2017-01-01

    The "critical zone", a region of speculated vascularity, is situated approximately 10 mm proximal to the insertion of the supraspinatus tendon. Despite its obvious role as an anatomical landmark demarcator, its patho-anatomic nature has been identified as the source of rotator cuff pathology. Although many studies have attempted to evaluate the vascularity of this region, the architecture regarding the exact length, width and shape of the critical zone, remains unreported. This study aimed to determine the shape and morphometry of the "critical zone" arthroscopically. The sample series, which was comprised of 38 cases (n = 38) specific to pathological types, employed an anatomical investigation of the critical zone during routine real-time arthroscopy. Demographic representation: i) sex: 19 males, 19 females; ii) age range: 18-76 years; iii) race: white (n = 29), Indian (n = 7) and coloured (n = 2). The incidence of shape and the mean lengths and widths of the critical zone were determined in accordance with the relevant demographic factors and patient history. Although the cresenteric shape was predominant, hemispheric and sail-shaped critical zones were also identified. The lengths and widths of the critical zone appeared markedly increased in male individuals. While the increase in age may account for the increased incidence of rotator cuff degeneration due to poor end-vascular supply, the additional factors of height and weight presented as major determinants of the increase in size of the critical zone. In addition, the comparisons of length and width with each other and shape yielded levels of significant difference, therefore indicating a directly proportional relationship between the length and width of the critical zone. This detailed understanding of the critical zone may prove beneficial for the success of post-operative rotator cuff healing.

  16. Outcome of Pediatric Critical Care Medicine Abstracts Presented at North American Academic National Meetings.

    PubMed

    Basu, Sonali; Pollack, Murray M

    2017-05-05

    Pediatric critical care medicine abstracts presented at North American national academic meetings have not been followed up to determine their publication outcomes. Our objective was to determine the following: 1) the proportion of these presentations that are published in peer-reviewed journals within 5 years; 2) the impact of trainee status on time to and success of publication; and 3) the quality of the research as reflected in the publishing journal's impact factor. Four years of abstracts (2007-2011) were reviewed from the American Academy of Pediatrics, Pediatric Academic Societies, and Society of Critical Care Medicine national meetings. Pediatric critical care medicine abstracts were delineated by the meeting or identified by keyword search. Data included mode of presentation, trainee status of first author, publication status within 5 years based on a PubMed search, trainee position in the journal of publication authorship list, and the impact factor of journal of publication. We evaluated 267 pediatric critical care medicine abstracts, 85-94 from each meeting. Overall, 41% were published, with the highest rate in Pediatric Academic Societies abstracts (54% Pediatric Academic Societies, 38% Society of Critical Care Medicine, and 33% American Academy of Pediatrics; p = 0.011). Mean time to publication was 22 (± 3) months and did not differ by conference or presentation mode. Journal first authorship was retained in 84%. Journal impact factor was highest in Society of Critical Care Medicine abstracts (3.38 Society of Critical Care Medicine, 2.64 Pediatric Academic Societies, and 1.92 American Academy of Pediatrics; p = 0.006). First author trainee status was not associated with publication rate, time to publication, and impact factor. A total of 100% of trainees but only 79% of nontrainees who published retained first authorship. Less than half of pediatric critical care medicine research abstracts presented at North American national academic meetings culminate in articles. Pediatric Academic Societies had the highest publication success rate, and Society of Critical Care Medicine abstracts were published in journals with the highest impact factors. All trainees who were first authors retained that status in the journal publications.

  17. A study into psychosocial factors as predictors of work-related fatigue.

    PubMed

    Rahman, Hanif Abdul; Abdul-Mumin, Khadizah; Naing, Lin

    2016-07-14

    To explore and determine relationship between psychosocial factors and work-related fatigue among emergency and critical care nurses in Brunei. Cross-sectional study conducted on all emergency and critical care nurses across Brunei public hospitals from February to April 2016. 201 nurses participated in the study (82% response rate). A total of 36% of the variance of chronic fatigue was explained by stress, trust in management, decision latitude, self-rated health, and work-family conflict. Burnout, self-rated health, commitment to workplace, and trust in management explained 30% of the variance of acute fatigue. Stress, work-family conflict and reward explained 28% of the variance of intershift recovery after controlling for significant sociodemographic variables. Smoking was identified as an important sociodemographic factor for work-related fatigue. Psychosocial factors were good predictors of work-related fatigue. A range of psychosocial factors were established, however more research is required to determine all possible causation factors of nurses' work-related fatigue.

  18. Some Findings on the Extent to Which Social and Educational Programs Affect the Quality of Life.

    ERIC Educational Resources Information Center

    Flanagan, John C.

    A national survey examined the factors that are primarily responsible in determining an individual's overall quality of life. Using the critical incident technique, researchers surveyed a representative sample of 50- and 70-year-old adults in the United States in order to determine which of 15 factors they felt had negative and positive effects on…

  19. Pressure Injuries in Critical Care: A Survey of Critical Care Nurses.

    PubMed

    Cox, Jill; Schallom, Marilyn

    2017-10-01

    Critical care nurses must be able to skillfully balance the prevention of adverse events such as pressure injuries in an environment with multiple competing and lifesaving technologies that often take precedent. Despite strategies to prevent them, pressure injuries do occur in intensive care unit patients, and consensus is building that some pressure injuries are unavoidable. To determine critical care nurses' attitudes toward prevention of pressure injury and the perceptions of frontline critical care nurses of specific risk factors associated with unavoidable pressure injuries. A descriptive cross-sectional survey design was used. An online survey was posted on the newsletter website of the American Association of Critical-Care Nurses in January 2016. An invitation to participate in the study was emailed to more than 3000 members of the association; 333 nurses responded, for a response rate of approximately 11%. Among the responders, 73% were employed as bedside critical care nurses. More than half (67%) thought that pressure injuries are avoidable, and 66% disagreed that pressure injury prevention was of less interest than other aspects of critical care. The top 2 risk factors for unavoidable pressure injuries were impaired tissue perfusion and impaired tissue oxygenation. Critical care nurses are steadfast stewards of safe patient care and think that pressure injury prevention is a crucial aspect of the care they deliver every day. The findings on risk factors for unavoidable pressure injuries mirrored those of experts and provide a layer of support for these factors. ©2017 American Association of Critical-Care Nurses.

  20. Overview of critical risk factors in Power-Two-Wheeler safety.

    PubMed

    Vlahogianni, Eleni I; Yannis, George; Golias, John C

    2012-11-01

    Power-Two-Wheelers (PTWs) constitute a vulnerable class of road users with increased frequency and severity of accidents. The present paper focuses of the PTW accident risk factors and reviews existing literature with regard to the PTW drivers' interactions with the automobile drivers, as well as interactions with infrastructure elements and weather conditions. Several critical risk factors are revealed with different levels of influence to PTW accident likelihood and severity. A broad classification based on the magnitude and the need for further research for each risk factor is proposed. The paper concludes by discussing the importance of dealing with accident configurations, the data quality and availability, methods implemented to model risk and exposure and risk identification which are critical for a thorough understanding of the determinants of PTW safety. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Residual Stresses and Critical Initial Flaw Size Analyses of Welds

    NASA Technical Reports Server (NTRS)

    Brust, Frederick W.; Raju, Ivatury, S.; Dawocke, David S.; Cheston, Derrick

    2009-01-01

    An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). A series of weld analyses are performed to determine the residual stresses in a critical region of the USS. Weld residual stresses both increase constraint and mean stress thereby having an important effect on the fatigue life. The purpose of the weld analyses was to model the weld process using a variety of sequences to determine the 'best' sequence in terms of weld residual stresses and distortions. The many factors examined in this study include weld design (single-V, double-V groove), weld sequence, boundary conditions, and material properties, among others. The results of this weld analysis are included with service loads to perform a fatigue and critical initial flaw size evaluation.

  2. e-Healthcare in India: critical success factors for sustainable health systems.

    PubMed

    Taneja, Udita; Sushil

    2007-01-01

    As healthcare enterprises seek to move towards an integrated, sustainable healthcare delivery model an IT-enabled or e-Healthcare strategy is being increasingly adopted. In this study we identified the critical success factors influencing the effectiveness of an e-Healthcare strategy in India. The performance assessment criteria used to measure effectiveness were increasing reach and reducing cost of healthcare delivery. A survey of healthcare providers was conducted. Analytic Hierarchy Process (AHP) and Interpretive Structural Modeling (ISM) were the analytical tools used to determine the relative importance of the critical success factors in influencing effectiveness of e-Healthcare and their interplay with each other. To succeed in e-Healthcare initiatives the critical success factors that need to be in place are appropriate government policies, literacy levels, and telecommunications and power infrastructure in the country. The focus should not be on the IT tools and biomedical engineering technologies as is most often the case. Instead the nontechnology factors such as healthcare provider and consumer mindsets should be addressed to increase acceptance of, and enhance the effectiveness of, sustainable e-Healthcare services.

  3. Critical soil water period for primary production in Chihuahuan Desert ecosystems

    USDA-ARS?s Scientific Manuscript database

    In desert ecosystems where water is the main limiting factor, it is expected that net primary production (NPP) is largely determined by precipitation. However, precipitation alone often explains only a small portion of the variation in NPP, and the critical precipitation period for NPP varies by pla...

  4. An exploratory review on critical factors of IBS formwork implementation for Malaysian construction stakeholders

    NASA Astrophysics Data System (ADS)

    Baharuddin, Mohd Nurfaisal; Bahardin, Nur Fadhilah; Zaidi, Mohd Azian; Lokman, Ikhwan; Nawi, Mohd Nasrun Mohd

    2016-08-01

    The goals of this paper is to analysed the critical factors of driving or hindering the used of Industrialised Building System (IBS) formwork system in the Malaysian construction industry. Based on the reviews of a previous research and related literature, this paper was identified four (4) critical factor that classified as a difficulties to the success of IBS formwork system application; The issues related to the lack of knowledge and awareness, high cost and financial barriers, lack of incentive and promotion and lack of enforcement for government policy were highlight as a key dimension for the uses of IBS formwork system to success. The objective of this paper is to determine the importance factors in implementing IBS formwork in Malaysia. A preliminary survey which qualitative research approach has been adopted for this study as to validate the factors which found in the literature study. Based on the result analysis, it can be confirmed that the entire factors in literature review are strongly related with challenges in construction industry.

  5. An artificial bee colony algorithm for locating the critical slip surface in slope stability analysis

    NASA Astrophysics Data System (ADS)

    Kang, Fei; Li, Junjie; Ma, Zhenyue

    2013-02-01

    Determination of the critical slip surface with the minimum factor of safety of a slope is a difficult constrained global optimization problem. In this article, an artificial bee colony algorithm with a multi-slice adjustment method is proposed for locating the critical slip surfaces of soil slopes, and the Spencer method is employed to calculate the factor of safety. Six benchmark examples are presented to illustrate the reliability and efficiency of the proposed technique, and it is also compared with some well-known or recent algorithms for the problem. The results show that the new algorithm is promising in terms of accuracy and efficiency.

  6. Minimum Winfree loop determines self-sustained oscillations in excitable Erdös-Rényi random networks.

    PubMed

    Qian, Yu; Cui, Xiaohua; Zheng, Zhigang

    2017-07-18

    The investigation of self-sustained oscillations in excitable complex networks is very important in understanding various activities in brain systems, among which the exploration of the key determinants of oscillations is a challenging task. In this paper, by investigating the influence of system parameters on self-sustained oscillations in excitable Erdös-Rényi random networks (EERRNs), the minimum Winfree loop (MWL) is revealed to be the key factor in determining the emergence of collective oscillations. Specifically, the one-to-one correspondence between the optimal connection probability (OCP) and the MWL length is exposed. Moreover, many important quantities such as the lower critical connection probability (LCCP), the OCP, and the upper critical connection probability (UCCP) are determined by the MWL. Most importantly, they can be approximately predicted by the network structure analysis, which have been verified in numerical simulations. Our results will be of great importance to help us in understanding the key factors in determining persistent activities in biological systems.

  7. Correlation Between Critical Thinking Disposition and Mental Self-Supporting Ability in Nursing Undergraduates: A Cross-Sectional Descriptive Study.

    PubMed

    Wu, Defang; Luo, Yang; Liao, Xinyu

    2017-02-01

    There is universal agreement on the essential role of critical thinking in nursing practice. Most studies into this topic have provided descriptive statistical information and insights on related external factors such as educational environment and teaching strategies. However, there has been limited research into the psychological factors that may predict the disposition of students toward critical thinking. This study explored the relationship between the disposition of nursing students toward critical thinking and their mental self-supporting ability to obtain a profile and determine the psychological predictors of critical thinking. A cross-sectional descriptive study was conducted in 2013 using a convenience sample from four nursing schools. Four hundred six Chinese nursing undergraduates completed two questionnaires including (a) the California Critical Thinking Disposition Inventory (Chinese version) and (b) the Mental Self-Supporting Questionnaire for University Students. Pearson's correlation and linear regression analysis were used to investigate the relationship between these two variables and the predicted positive psychological qualities for the critical thinking disposition of participants. Average participant scores for critical thinking disposition and mental self-supporting were 280.91 ± 28.43 and 76.40 ± 8.47, respectively. Positive correlations were observed between these two variables (r = .583, p < .01) and participants' self-decision, self-cognition, self-confidence, and self-responsibility, which suggest that these factors play a significant role in critical thinking disposition (R = .435, p < .01). The participants earned midlevel scores for both disposition toward critical thinking and mental self-supporting abilities.The four factors that had a major influence on critical thinking disposition included self-decision, self-cognition, self-confidence, and self-responsibility. Nursing educators should focus on improving the critical thinking ability of their students in these four aspects.

  8. Use of combined biogeochemical model approaches and empirical data to assess critical loads of nitrogen

    Treesearch

    Mark Fenn; Charles Driscoll; Quingtao Zhou; Leela Rao; Thomas Meixner; Edith Allen; Fengming Yuan; Timothy Sullivan

    2015-01-01

    Empirical and dynamic biogeochemical modelling are complementary approaches for determining the critical load (CL) of atmospheric nitrogen (N) or other constituent deposition that an ecosystem can tolerate without causing ecological harm. The greatest benefits are obtained when these approaches are used in combination. Confounding environmental factors can complicate...

  9. Perspectives of General and Special Educators on Fostering Self-Determination in Elementary and Middle Schools

    ERIC Educational Resources Information Center

    Stang, Kristin K.; Carter, Erik W.; Lane, Kathleen Lynne; Pierson, Melinda R.

    2009-01-01

    Recognizing that many youth with disabilities lack critical self-determination skills and that such deficits may be a contributing factor to disappointing postschool outcomes, educators and researchers have called for increased attention to promoting student self-determination in the early grades. The authors queried 891 elementary and middle…

  10. Scheduling Real-Time Mixed-Criticality Jobs

    NASA Astrophysics Data System (ADS)

    Baruah, Sanjoy K.; Bonifaci, Vincenzo; D'Angelo, Gianlorenzo; Li, Haohan; Marchetti-Spaccamela, Alberto; Megow, Nicole; Stougie, Leen

    Many safety-critical embedded systems are subject to certification requirements; some systems may be required to meet multiple sets of certification requirements, from different certification authorities. Certification requirements in such "mixed-criticality" systems give rise to interesting scheduling problems, that cannot be satisfactorily addressed using techniques from conventional scheduling theory. In this paper, we study a formal model for representing such mixed-criticality workloads. We demonstrate first the intractability of determining whether a system specified in this model can be scheduled to meet all its certification requirements, even for systems subject to two sets of certification requirements. Then we quantify, via the metric of processor speedup factor, the effectiveness of two techniques, reservation-based scheduling and priority-based scheduling, that are widely used in scheduling such mixed-criticality systems, showing that the latter of the two is superior to the former. We also show that the speedup factors are tight for these two techniques.

  11. Time Factor in the Theory of Anthropogenic Risk Prediction in Complex Dynamic Systems

    NASA Astrophysics Data System (ADS)

    Ostreikovsky, V. A.; Shevchenko, Ye N.; Yurkov, N. K.; Kochegarov, I. I.; Grishko, A. K.

    2018-01-01

    The article overviews the anthropogenic risk models that take into consideration the development of different factors in time that influence the complex system. Three classes of mathematical models have been analyzed for the use in assessing the anthropogenic risk of complex dynamic systems. These models take into consideration time factor in determining the prospect of safety change of critical systems. The originality of the study is in the analysis of five time postulates in the theory of anthropogenic risk and the safety of highly important objects. It has to be stressed that the given postulates are still rarely used in practical assessment of equipment service life of critically important systems. That is why, the results of study presented in the article can be used in safety engineering and analysis of critically important complex technical systems.

  12. Cytokines and the neurodevelopmental basis of mental illness

    PubMed Central

    Ratnayake, Udani; Quinn, Tracey; Walker, David W.; Dickinson, Hayley

    2013-01-01

    Epidemiological studies suggest that prenatal exposure to different types of viral or bacterial infections may be associated with similar outcomes; i.e., an increased risk of mental illness disorders in the offspring. Infections arising from various causes have similar debilitating effects in later life, suggesting that the exact pathogen may not be the critical factor in determining the neurological and cognitive outcome in the offspring. Instead, it is thought that response of the innate immune system, specifically the increased production of inflammatory cytokines, may be the critical mediator in altering fetal brain development pre-disposing the offspring to mental illness disorders later in life. Inflammatory cytokines are essential for normal brain development. Factors such as the site of cytokine production, a change in balance between anti- and pro- inflammatory cytokines, placental transfer of cytokines, the effects of cytokines on glial cells, and the effects of glucocorticoids are important when evaluating the impact of maternal infection on fetal brain development. Although it is clear that cytokines are altered in the fetal brain following maternal infection, further evidence is required to determine if cytokines are the critical factor that alters the trajectory of brain development, subsequently leading to postnatal behavioral and neurological abnormalities. PMID:24146637

  13. Concentration-dependent effect of hypocalcaemia on mortality of patients with critical bleeding requiring massive transfusion: a cohort study.

    PubMed

    Ho, K M; Leonard, A D

    2011-01-01

    Mortality of patients with critical bleeding requiring massive transfusion is high. Although hypothermia, acidosis and coagulopathy have been well described as important determinants of mortality in patients with critical bleeding requiring massive transfusion, the risk factors and outcome associated with hypocalcaemia in these patients remain uncertain. This cohort study assessed the relationship between the lowest ionised calcium concentration during the 24-hour period of critical bleeding and the hospital mortality of 352 consecutive patients, while adjusting for diagnosis, acidosis, coagulation results, transfusion requirements and use of recombinant factor VIIa. Hypocalcaemia was common (mean concentrations 0.77 mmol/l, SD 0.19) and had a linear; concentration-dependent relationship with mortality (odds ratio [OR] 1.25 per 0.1 mmol/l decrement, 95% confidence interval [CI]: 1.04 to 1.52; P = 0.02). Hypocalcaemia accounted for 12.5% of the variability and was more important than the lowest fibrinogen concentrations (10.8%), acidosis (7.9%) and lowest platelet counts (7.7%) in predicting hospital mortality. The amount of fresh frozen plasma transfused (OR 1.09 per unit, 95% CI: 1.02 to 1.17; P = 0.02) and acidosis (OR 1.45 per 0.1 decrement, 95% CI: 1.19 to 1.72; P = 0.01) were associated with the occurrence of severe hypocalcaemia (< 0.8 mmol/l). In conclusion, ionised calcium concentrations had an inverse concentration-dependent relationship with mortality of patients with critical bleeding requiring massive transfusion. Both acidosis and the amount of fresh frozen plasma transfused were the main risk factors for severe hypocalcaemia. Further research is needed to determine whether preventing ionised hypocalcaemia can reduce mortality of patients with critical bleeding requiring massive transfusion.

  14. Risk factors for shoulder pain and injury in swimmers: A critical systematic review.

    PubMed

    Hill, Lee; Collins, Malcolm; Posthumus, Michael

    2015-11-01

    Swimming is one of the most popular recreational and competitive sporting activities. In the 2013/2014 swimming season, 9630 men and 12,333 women were registered with the National Collegiate Athletics Association in the USA. The repetitive nature of the swimming stroke and demanding training programs of its athletes raises a number of concerns regarding incidence and severity of injuries that a swimmer might experience during a competitive season. A number of risk factors have previously been identified but the level of evidence from individual studies, as well as the level of certainty that these factors predispose a swimmer to pain and injury, to our knowledge has yet to be critically evaluated in a systematic review. Therefore, the primary objective of this review is to conduct a systematic review to critically assess the published evidence for risk factors that may predispose a swimmer to shoulder pain and injury. Three electronic databases, ScienceDirect, PubMed and SpringerLink, were searched using keywords "(Injury OR pain) AND (Swim*)" and "(Shoulder) AND (Swim*)". Based on the inclusion and exclusion criteria, 2731 unique titles were identified and were analyzed to a final 29 articles. Only articles with a level of evidence of I, II and III were included according to robust study design and data analysis. The level of certainty for each risk factor was determined. No studies were determined to have a high level of certainty, clinical joint laxity and instability, internal/external rotation, previous history of pain and injury and competitive level were determined to have a moderate level of certainty. All other risk factors were evaluated as having a low level of certainty. Although several risk factors were identified from the reviewed studies, prospective cohort studies, larger sample sizes, consistent and robust measures of risk should be employed in future research.

  15. Patient Bypass Behavior and Critical Access Hospitals: Implications for Patient Retention

    ERIC Educational Resources Information Center

    Liu, Jiexin (Jason); Bellamy, Gail R.; McCormick, Melissa

    2007-01-01

    Purpose: To assess the extent of bypass for inpatient care among patients living in Critical Access Hospital (CAH) service areas, and to determine factors associated with bypass, the reasons for bypass, and what CAHs can do to retain patients locally. Methods: Six hundred and forty-seven subjects, aged 18 years and older, who had been admitted to…

  16. The critical velocity of a body towed by a cable from an airplane

    NASA Technical Reports Server (NTRS)

    Koning, C; De Haas, T P

    1937-01-01

    It is sufficient to consider only the equations of motion of the towed body whereas those of the cable may be left out of consideration. The result obtained makes it possible to determine which factors affect the critical velocity and what modifications of the instrument are necessary for extending the upper limit of that velocity.

  17. Validation of smoke plume rise models using ground based lidar

    Treesearch

    Cyle E. Wold; Shawn Urbanski; Vladimir Kovalev; Alexander Petkov; Wei Min Hao

    2010-01-01

    Biomass fires can significantly degrade regional air quality. Plume rise height is one of the critical factors determining the impact of fire emissions on air quality. Plume rise models are used to prescribe the vertical distribution of fire emissions which are critical input for smoke dispersion and air quality models. The poor state of model evaluation is due in...

  18. Determinants of High Schools' Advanced Course Offerings

    ERIC Educational Resources Information Center

    Iatarola, Patrice; Conger, Dylan; Long, Mark C.

    2011-01-01

    This article examines the factors that determine a high school's probability of offering Advanced Placement (AP) and International Baccalaureate (IB) courses. The likelihood that a school offers advanced courses, and the number of sections that it offers, is largely driven by having a critical mass of students who enter high school with…

  19. The drive to strive: goal generation based on current needs

    PubMed Central

    Murray, Elisabeth A.; Rudebeck, Peter H.

    2013-01-01

    Hungry animals are influenced by a multitude of different factors when foraging for sustenance. Much of the work on animal foraging has focused on factors relating to the amount of time and energy animals expend searching for and harvesting foods. Models that emphasize such factors have been invaluable in determining when it is beneficial for an animal to search for pastures new. When foraging, however, animals also have to determine how to direct their search. For what food should they forage? There is no point searching for more of a particular food when you are sated from eating it. Here we review work in macaques and humans that has sought to reveal the neural circuits critical for determining the subjective value of different foods and associated objects in our environment and tracking this value over time. There is mounting evidence that a network composed of the orbitofrontal cortex (OFC), amygdala, and medial thalamus is critical for linking objects in the environment with food value and adjusting those valuations in real time based on current biological needs. Studies using temporary inactivation methods have revealed that the amygdala and OFC play distinct yet complementary roles in this valuation process. Such a network for determining the subjective value of different foods and, by extension, associated objects, must interact with systems that determine where and for how long to forage. Only by efficiently incorporating these two factors into their decisions will animals be able to achieve maximal fitness. PMID:23818876

  20. Lower HIV prevalence among Asian/Pacific Islander men who have sex with men: a critical review for possible reasons.

    PubMed

    Wei, Chongyi; Raymond, H Fisher; Wong, Frank Y; Silvestre, Anthony J; Friedman, Mark S; Documét, Patricia; McFarland, Willi; Stall, Ron

    2011-04-01

    We conducted a critical literature review for possible reasons that may explain the lower HIV prevalence observed among API MSM compared to MSM of other races/ethnicities. Trends emerging from the literature suggest that traditional individual-level factors-unprotected anal intercourse, substance use, STD prevalence, rates and frequency of HIV testing, and utilization of HIV prevention services-do not appear to be related to the lower HIV prevalence among API MSM. Some evidence suggests that socio-cultural and structural factors might be the more critical forces in determining racial/ethnic disparities of HIV among MSM. For API MSM, these factors include structures of sexual networks, access to and reception of medical care and treatment among HIV-positive MSM, and influences of different levels and types of acculturation. Moreover, emerging risk reduction strategies, such as seroadaptive behaviors, could play a role. Future research should address these factors in intervention design. In addition, better theories of resilience and measurement of strengths and protective factors are needed to enhance the efficacy of HIV interventions.

  1. The influence of stem design on critical squeaking friction with ceramic bearings.

    PubMed

    Fan, Na; Morlock, Michael M; Bishop, Nicholas E; Huber, Gerd; Hoffmann, Norbert; Ciavarella, Michele; Chen, Guang X; Hothan, Arne; Witt, Florian

    2013-10-01

    Ceramic-on-ceramic hip joints have been reported to squeak, a phenomenon that may occur in compromised lubrication conditions. One factor related to the incidence of in vivo squeaking is the stem design. However, it has not yet been possible to relate stem design to squeaking in deteriorating lubrication conditions. The purpose of this study was to determine critical friction factors for different stem designs. A hip simulator was used to measure the friction factor of a ceramic bearing with different stem designs and gradually deteriorating lubrication represented by evaporation of a volatile fluid lubricant. The critical squeaking friction factor was measured at the onset of squeaking for each stem. Critical friction was higher for the long cobalt chrome (0.32 ± 0.02) and short titanium stems (0.39 ± 0.02) in comparison with a long titanium stem (0.29 ± 0.02). The onset of squeaking occurred at a friction factor lower than that measured for dry conditions, in which squeaking is usually investigated experimentally. The results suggest that shorter or heavier stems might limit the possibility of squeaking as lubrication deteriorates. The method developed can be used to investigate the influence of design parameters on squeaking probability. Copyright © 2013 Orthopaedic Research Society.

  2. Critical factors for the recovery of marine mammals.

    PubMed

    Lotze, Heike K; Flemming, Joanna Mills; Magera, Anna M

    2017-12-01

    {en} Over the past decades, much research has focused on understanding the critical factors for marine extinctions with the aim of preventing further species losses in the oceans. Although conservation and management strategies are enabling several species and populations to recover, others remain at low abundance levels or continue to decline. To understand these discrepancies, we used a published database on abundance trends of 137 populations of marine mammals worldwide and compiled data on 28 potentially critical factors for recovery. We then applied random forests and additive mixed models to determine which intrinsic and extrinsic factors are critical for the recovery of marine mammals. A mix of life-history characteristics, ecological traits, phylogenetic relatedness, population size, geographic range, human impacts, and management efforts explained why populations recovered or not. Consistently, species with lower age at maturity and intermediate habitat area were more likely to recover, which is consistent with life-history and ecological theory. Body size, trophic level, social interactions, dominant habitat, ocean basin, and habitat disturbance also explained some differences in recovery patterns. Overall, a variety of intrinsic and extrinsic factors were important for species' recovery, pointing to cumulative effects. Our results provide insight for improving conservation and management strategies to enhance recoveries in the future. © 2017 Society for Conservation Biology.

  3. Clinical and critical care concerns in severely ill obese patient

    PubMed Central

    Bajwa, Sukhminder Jit Singh; Sehgal, Vishal; Bajwa, Sukhwinder Kaur

    2012-01-01

    The incidence of obesity has acquired an epidemic proportion throughout the globe. As a result, increasing number of obese patients is being presented to critical care units for various indications. The attending intensivist has to face numerous challenges during management of such patients. Almost all the organ systems are affected by the impact of obesity either directly or indirectly. The degree of obesity and its prolong duration are the main factors which determine the harmful effect of obesity on human body. The present article reviews few of the important clinical and critical care concerns in critically ill obese patients. PMID:23087857

  4. The heuristics of nurse responsiveness to critical patient monitor and ventilator alarms in a private room neonatal intensive care unit.

    PubMed

    Joshi, Rohan; Mortel, Heidi van de; Feijs, Loe; Andriessen, Peter; Pul, Carola van

    2017-01-01

    Alarm fatigue is a well-recognized patient safety concern in intensive care settings. Decreased nurse responsiveness and slow response times to alarms are the potentially dangerous consequences of alarm fatigue. The aim of this study was to determine the factors that modulate nurse responsiveness to critical patient monitor and ventilator alarms in the context of a private room neonatal intensive care setting. The study design comprised of both a questionnaire and video monitoring of nurse-responsiveness to critical alarms. The Likert scale questionnaire, comprising of 50 questions across thematic clusters (critical alarms, yellow alarms, perception, design, nursing action, and context) was administered to 56 nurses (90% response rate). Nearly 6000 critical alarms were recorded from 10 infants in approximately 2400 hours of video monitoring. Logistic regression was used to identify patient and alarm-level factors that modulate nurse-responsiveness to critical alarms, with a response being defined as a nurse entering the patient's room within the 90s of the alarm being generated. Based on the questionnaire, the majority of nurses found critical alarms to be clinically relevant even though the alarms did not always mandate clinical action. Based on video observations, for a median of 34% (IQR, 20-52) of critical alarms, the nurse was already present in the room. For the remaining alarms, the response rate within 90s was 26%. The median response time was 55s (IQR, 37-70s). Desaturation alarms were the most prevalent and accounted for more than 50% of all alarms. The odds of responding to bradycardia alarms, compared to desaturation alarms, were 1.47 (95% CI = 1.21-1.78; <0.001) while that of responding to a ventilator alarm was lower at 0.35 (95% CI = 0.27-0.46; p <0.001). For every 20s increase in the duration of an alarm, the odds of responding to the alarm (within 90s) increased to 1.15 (95% CI = 1.1-1.2; p <0.001). The random effect per infant improved the fit of the model to the data with the response times being slower for infants suffering from chronic illnesses while being faster for infants who were clinically unstable. Even though nurses respond to only a fraction of all critical alarms, they consider the vast majority of critical and yellow alarms as useful and relevant. When notified of a critical alarm, they seek waveform information and employ heuristics in determining whether or not to respond to the alarm. Amongst other factors, the category and duration of critical alarms along with the clinical status of the patient determine nurse-responsiveness to alarms.

  5. The heuristics of nurse responsiveness to critical patient monitor and ventilator alarms in a private room neonatal intensive care unit

    PubMed Central

    van de Mortel, Heidi; Feijs, Loe; Andriessen, Peter; van Pul, Carola

    2017-01-01

    Aim Alarm fatigue is a well-recognized patient safety concern in intensive care settings. Decreased nurse responsiveness and slow response times to alarms are the potentially dangerous consequences of alarm fatigue. The aim of this study was to determine the factors that modulate nurse responsiveness to critical patient monitor and ventilator alarms in the context of a private room neonatal intensive care setting. Methods The study design comprised of both a questionnaire and video monitoring of nurse-responsiveness to critical alarms. The Likert scale questionnaire, comprising of 50 questions across thematic clusters (critical alarms, yellow alarms, perception, design, nursing action, and context) was administered to 56 nurses (90% response rate). Nearly 6000 critical alarms were recorded from 10 infants in approximately 2400 hours of video monitoring. Logistic regression was used to identify patient and alarm-level factors that modulate nurse-responsiveness to critical alarms, with a response being defined as a nurse entering the patient’s room within the 90s of the alarm being generated. Results Based on the questionnaire, the majority of nurses found critical alarms to be clinically relevant even though the alarms did not always mandate clinical action. Based on video observations, for a median of 34% (IQR, 20–52) of critical alarms, the nurse was already present in the room. For the remaining alarms, the response rate within 90s was 26%. The median response time was 55s (IQR, 37-70s). Desaturation alarms were the most prevalent and accounted for more than 50% of all alarms. The odds of responding to bradycardia alarms, compared to desaturation alarms, were 1.47 (95% CI = 1.21–1.78; <0.001) while that of responding to a ventilator alarm was lower at 0.35 (95% CI = 0.27–0.46; p <0.001). For every 20s increase in the duration of an alarm, the odds of responding to the alarm (within 90s) increased to 1.15 (95% CI = 1.1–1.2; p <0.001). The random effect per infant improved the fit of the model to the data with the response times being slower for infants suffering from chronic illnesses while being faster for infants who were clinically unstable. Discussion Even though nurses respond to only a fraction of all critical alarms, they consider the vast majority of critical and yellow alarms as useful and relevant. When notified of a critical alarm, they seek waveform information and employ heuristics in determining whether or not to respond to the alarm. Conclusion Amongst other factors, the category and duration of critical alarms along with the clinical status of the patient determine nurse-responsiveness to alarms. PMID:28981515

  6. Competitive strategy for successful hospital management.

    PubMed

    Cleverley, W O; Harvey, R K

    1992-01-01

    This study examined financial and operating data for approximately 1,000 U.S. hospitals categorized by Medicare as "large urban" to determine critical relationships between business strategy and financial performance. Cost control was found to be the most important factor influencing financial performance. Other factors of importance included market share, diversification, and financing policy.

  7. Urban Teachers' Perceptions of Critical Variables in Measuring Teacher Effectiveness

    ERIC Educational Resources Information Center

    Flores, JuanPablo

    2013-01-01

    This quantitative and qualitative study sought to examine the factors that teachers in a poor socio-economic, high-minority, urban, inner-city school district determined were important when gauging their effectiveness in the classroom. The study focused on the selection of specific factors by approximately seventy-five teachers from seven of eight…

  8. Student Perceptions and Motivation in the Classroom: Exploring Relatedness and Value

    ERIC Educational Resources Information Center

    Kaufman, Annette; Dodge, Tonya

    2009-01-01

    According to Self-Determination Theory, feelings of relatedness and value of a behavior are critical factors that affect internalization and integration. The purpose of the current study was to identify factors that influence relatedness and value in an academic setting. Specifically, the study investigated the effects of autonomy, mastery goals,…

  9. Tables of critical-flow functions and thermodynamic properties for methane and computational procedures for both methane and natural gas

    NASA Technical Reports Server (NTRS)

    Johnson, R. C.

    1972-01-01

    Procedures for calculating the mass flow rate of methane and natural gas through nozzles are given, along with the FORTRAN 4 subroutines used to make these calculations. Three sets of independent variables are permitted in these routines. In addition to the plenum pressure and temperature, the third independent variable is either nozzle exit pressure, Mach number, or temperature. A critical-flow factor that becomes a convenient means for determining the mass flow rate of methane through critical-flow nozzles is tabulated. Other tables are included for nozzle throat velocity and critical pressure, density, and temperature ratios, along with some thermodynamic properties of methane, including compressibility factor, enthalpy, entropy, specific heat, specific-heat ratio, and speed of sound. These tabulations cover a temperature range from 120 to 600 K and pressures to 3 million N/sq m.

  10. Lactate-related factors as a critical determinant of endurance.

    PubMed

    Tanaka, K

    1990-04-01

    Many interrelated physiological and/or morphological factors have been demonstrated to influence endurance exercise performance. Some of these factors include skeletal musculature, running economy, maximal oxygen uptake (VO2max), maximal steady state (MSS), onset of blood lactate accumulation (OBLA), onset of plasma lactate accumulation (OPLA), and anaerobic (or lactate) threshold (AT or LT). The present paper focuses mainly on VO2max, MSS, OBLA, OPLA and LT, all of which have been postulated as a prerequisite in endurance exercise success. This paper consists of: (1) significance of La-related variables, (2) longitudinal studies, (3) comments, and (4) conclusion. Briefly, it is suggested that estimation of endurance exercise potential could be obtained with relatively high precision using laboratoriously measured La-related variables. The most critical determinant of endurance exercise performance such as marathon time is considered running velocity (V) at which LT is detected (V / LT), VO2 / LT, or V / MSS, while V / OBLA appears to be the best predictor of performance in endurance events of 16 km or shorter distances.

  11. The importance of humans in the dispersal and spread of Phytophthora ramorum at local, landscape, and regional scales

    Treesearch

    J. Hall Cushman; Ross Meentemeyer

    2006-01-01

    Determining how Phytophthora ramorum is dispersed across the landscape is critical for understanding the ecology and epidemiology of this influential pathogen. To date, researchers have shown that abiotic factors – such as rain-splash, wind-blown rain and down-stream transport of inoculum – are critical mechanisms for the dispersal of this pathogen....

  12. Finite-temperature spin dynamics in a perturbed quantum critical Ising chain with an E₈ symmetry.

    PubMed

    Wu, Jianda; Kormos, Márton; Si, Qimiao

    2014-12-12

    A spectrum exhibiting E₈ symmetry is expected to arise when a small longitudinal field is introduced in the transverse-field Ising chain at its quantum critical point. Evidence for this spectrum has recently come from neutron scattering measurements in cobalt niobate, a quasi-one-dimensional Ising ferromagnet. Unlike its zero-temperature counterpart, the finite-temperature dynamics of the model has not yet been determined. We study the dynamical spin structure factor of the model at low frequencies and nonzero temperatures, using the form factor method. Its frequency dependence is singular, but differs from the diffusion form. The temperature dependence of the nuclear magnetic resonance (NMR) relaxation rate has an activated form, whose prefactor we also determine. We propose NMR experiments as a means to further test the applicability of the E₈ description for CoNb₂O₆.

  13. Determination of Visual Figure and Ground in Dynamically Deforming Shapes

    ERIC Educational Resources Information Center

    Barenholtz, Elan; Feldman, Jacob

    2006-01-01

    Figure/ground assignment--determining which part of the visual image is foreground and which background--is a critical step in early visual analysis, upon which much later processing depends. Previous research on the assignment of figure and ground to opposing sides of a contour has almost exclusively involved static geometric factors--such as…

  14. Exertional heat stroke in navy and marine personnel: a hot topic.

    PubMed

    Goforth, Carl W; Kazman, Josh B

    2015-02-01

    Although exertional heat stroke is considered a preventable condition, this life-threatening emergency affects hundreds of military personnel annually. Because heat stroke is preventable, it is important that Navy critical care nurses rapidly recognize and treat heat stroke casualties. Combined intrinsic and extrinsic risk factors can quickly lead to heat stroke if not recognized by deployed critical care nurses and other first responders. In addition to initial critical care nursing interventions, such as establishing intravenous access, determining body core temperature, and assessing hemodynamic status, aggressive cooling measures should be initiated immediately. The most important determinant in heat stroke outcome is the amount of time that patients sustain hyperthermia. Heat stroke survival approaches 100% when evidence-based cooling guidelines are followed, but mortality from heat stroke is a significant risk when care is delayed. Navy critical care and other military nurses should be aware of targeted assessments and cooling interventions when heat stroke is suspected during military operations. ©2015 American Association of Critical-Care Nurses.

  15. Eight critical factors in creating and implementing a successful simulation program.

    PubMed

    Lazzara, Elizabeth H; Benishek, Lauren E; Dietz, Aaron S; Salas, Eduardo; Adriansen, David J

    2014-01-01

    Recognizing the need to minimize human error and adverse events, clinicians, researchers, administrators, and educators have strived to enhance clinicians' knowledge, skills, and attitudes through training. Given the risks inherent in learning new skills or advancing underdeveloped skills on actual patients, simulation-based training (SBT) has become an invaluable tool across the medical education spectrum. The large simulation, training, and learning literature was used to provide a synthesized yet innovative and "memorable" heuristic of the important facets of simulation program creation and implementation, as represented by eight critical "S" factors-science, staff, supplies, space, support, systems, success, and sustainability. These critical factors advance earlier work that primarily focused on the science of SBT success, to also include more practical, perhaps even seemingly obvious but significantly challenging components of SBT, such as resources, space, and supplies. SYSTEMS: One of the eight critical factors-systems-refers to the need to match fidelity requirements to training needs and ensure that technological infrastructure is in place. The type of learning objectives that the training is intended to address should determine these requirements. For example, some simulators emphasize physical fidelity to enable clinicians to practice technical and nontechnical skills in a safe environment that mirrors real-world conditions. Such simulators are most appropriate when trainees are learning how to use specific equipment or conduct specific procedures. The eight factors-science, staff, supplies, space, support, systems, success, and sustainability-represent a synthesis of the most critical elements necessary for successful simulation programs. The order of the factors does not represent a deliberate prioritization or sequence, and the factors' relative importance may change as the program evolves.

  16. Porosity determination of thermal barrier coatings

    NASA Technical Reports Server (NTRS)

    Van Roode, Mark; Beardsley, Brad

    1988-01-01

    Coating porosity is believed to be a critical factor for the thermal conductivity of thermal barrier coatings (TBCs). A number of different techniques have been used to determine the porosities of thermal barrier coatings for diesel applications as part of a NASA/DOE sponsored study. A comparison is made between methods based on water immersion, optical microscopy, eddy current thickness measurements, and Archimedes principle for TBC porosity determination.

  17. How climatic conditions, site, and soil characteristics affect tree growth and critical loads of nitrogen for northeastern tree species

    Treesearch

    Molly J. Robin-Abbott; Linda H. Pardo

    2017-01-01

    Forest health is affected by multiple factors, including topography, climate, and soil characteristics, as well as pests, pathogens, competitive interactions, and anthropogenic deposition. Species within a stand may respond differently to site factors depending on their physiological requirements for growth, survival, and regeneration. We determined optimal ranges of...

  18. Mineral Fiber Toxicology

    EPA Science Inventory

    The chemical and physical properties of different forms of mineral fibers impact biopersistence and pathology in the lung. Fiber chemistry, length, aspect ratio, surface area and dose are critical factors determining mineral fiber-associated health effects including cancer and as...

  19. Collaboration and critical thinking in an online chemistry environment

    NASA Astrophysics Data System (ADS)

    Kershisnik, Elizabeth Irene

    The purpose of this dissertation was to examine collaboration and student's critical thinking and cognitive achievement within online chemistry courses. This quantitative study focused on the apparent lack of research relating collaboration and critical thinking in online science courses. Collaboration was determined using the small group collaboration model coding scheme, which examined student postings in asynchronous discussion forums for quantity, equality, and shareness. Critical thinking was measured using the chemistry concept reasoning test, the online self-diagnostic test, and also asynchronous student homework discussion postings that were coded using the community of inquiry cognitive presence indicators. Finally cognitive achievement was determined using quiz scores and the student's final grade. Even though no significant findings were revealed in this exploratory quasi-experimental study, this research did add to the educational technology knowledge base since very few studies have investigated the chemistry discipline in an online environment. Continued research in this area is vital to understanding how critical thinking progresses, how it can be assessed, and what factors in the classroom, be it virtual or face-to-face, have the greatest effect on critical thinking.

  20. The critical success factor approach to strategic alignment: seeking a trail from a health organization's goals to its management information infrastructure.

    PubMed

    Tan, J K

    1999-11-01

    The critical success factor (CSF) approach is a technique that will aid health administrators, planners and managers to identify, specify and sort among the most relevant and critical factors determining an organization's survival and success. Following a top-down management perspective, this paper discusses the CSF methodology as a strategic information management process comprising several important phases: (i) understanding the external factors such as the organization's industry, market and environment; (ii) achieving strong support and championship from top management; (iii) encouraging the proactive involvement of management and staff in generic CSF identification; (iv) educating and directing the participation of staff members in CSF verification and further refinement of generic CSFs into specific CSFs; and (v) aggregating, prioritizing and translating activity-related CSFs into organizational information requirements for the design of the organization's management information infrastructure. The implementation of this CSF approach is illustrated in the context of a British Columbia community hospital, with insights provided into key issues for future health researchers and practitioners.

  1. Terrorist bombings. Lessons learned from Belfast to Beirut.

    PubMed Central

    Frykberg, E R; Tepas, J J

    1988-01-01

    Experience in the management of mass casualties following a disaster is relatively sparse. The terrorist bombing serves as a timely and effective model for the analysis of patterns of injury and mortality and the determination of the factors influencing casualty survival in the wake of certain forms of disaster. For this purpose, a review of the published experience with terrorist bombings was carried out, providing a study population of 3357 casualties from 220 incidents worldwide. There were 2934 immediate survivors of these incidents (87%), of whom 881 (30%) were hospitalized. Forty deaths ultimately occurred among these survivors (1.4%), 39 of whom were among those hospitalized (4.4%). Injury severity was determined from available data for 1339 surviving casualties, 251 of whom were critically injured (18.7%). Of this population evaluable for injury severity, there were 31 late deaths, all of which occurred among those critically injured, accounting for an overall "critical mortality" rate of 12.4%. Overall triage efficiency was characterized by a mean overtriage rate (noncritically injured among those hospitalized or evacuated) of 59%, and a mean undertriage rate (critically injured among those not hospitalized or evacuated) of .05%. Multiple linear regression analysis of all major bombing incidents demonstrated a direct linear relationship between overtriage and critical mortality (r2 = .845), and an inversely proportional relationship between triage discrimination and critical mortality (r2 = 0.855). Although head injuries predominated in both immediate (71%) and late (52%) fatalities, injury to the abdomen carried the highest specific mortality rate (19%) of any single body system injury among immediate survivors. These data clearly document the importance of accurate triage as a survival determinant for critically injured casualties of these disasters. Furthermore, the data suggest that explosive force, time interval from injury to treatment, and anatomic site of injury are all factors that correlated with the ultimate outcome of terrorist bombing victims. Critical analysis of past disasters should allow for sufficient preparation so as to minimize casualty mortality in the future. Images Fig. 1. Fig. 2. PMID:3056287

  2. Faying Surface Lubrication Effects on Nut Factors

    NASA Technical Reports Server (NTRS)

    Taylor, Deneen M.; Morrison, Raymond F.

    2006-01-01

    Bolted joint analysis typically is performed using nut factors derived from textbooks and procedures from program requirement documents. Joint specific testing was performed for a critical International Space Station (ISS) joint. Test results indicate that for some configurations the nut factor may be significantly different than accepted textbook values. This paper presents results of joint specific testing to aid in determining if joint specific testing should be performed to insure required preloads are obtained.

  3. How does race/ethnicity influence pharmacological response to asthma therapies?

    PubMed

    Cazzola, Mario; Calzetta, Luigino; Matera, Maria Gabriella; Hanania, Nicola A; Rogliani, Paola

    2018-04-01

    Our understanding of whether and/or how ethnicity influences pharmacological response to asthma therapies is still very scarce. A possible explanation for the increased asthma treatment failures observed in ethnic and racial minorities receiving asthma therapies is that some of these groups may have a pharmacogenomic predisposition to either nonresponse or to adverse response with a specific class of drugs. However, the effects of ethnicity on pharmacological response to asthma therapies are also, and mainly, determined by socioeconomic and environmental factors to a varying extent, depending on the ethnic groups. Areas covered: Genetic, socioeconomic and environmental factors that can affect the pharmacotherapeutic responses to asthma medications and their link(s) to race/ethnicity have been examined and critically discussed. Expert opinion: Differences in genetic ancestry are definitely non-modifiable factors, but socioeconomic and environmental disadvantages are all factors that can be modified. It is likely that improved outcomes may be achieved when tailored and multifaceted approaches that include home, school, and clinician-based interventions are implemented. Consequently, it is critical to determine if a clinical intervention programme combined with implementation strategies that attempt to reduce inequalities can reduce asthma disparities, including the influence of ethnicity and race on pharmacological response to asthma therapies.

  4. Business dynamics of lithography at very low k1 factors

    NASA Astrophysics Data System (ADS)

    Harrell, Sam; Preil, Moshe E.

    1999-07-01

    Lithography is the largest capital investment and the largest operating cost component of leading edge semiconductor fabs. In addition, it is the dominant factor in determining the performance of a semiconductor device and is important in determining the yield and thus the economics of a semiconductor circuit. To increase competitiveness and broaden adoption of circuits and the end products in which they are used, there has been and continues to be a dramatic acceleration in the industry roadmap. A critical factor in the acceleration is driving the lithographic images to smaller feature size. There has always been economic tension between the pace of change and the resultant circuit cost. The genius of the semiconductor industry has been in its ability to balance its technology with economic factors and deliver outstanding value to those using the circuits to add value to their end products. The critical question today is whether optical lithography can be successfully and economically extended to maintain and improve the economic benefits of higher complexity circuits. In this paper we will discuss some of these significant tradeoffs required to maintain optically based lithographic progress on the roadmap at acceptable cost.

  5. Nuclear Localization of the C1 Factor (Host Cell Factor) in Sensory Neurons Correlates with Reactivation of Herpes Simplex Virus from Latency

    NASA Astrophysics Data System (ADS)

    Kristie, Thomas M.; Vogel, Jodi L.; Sears, Amy E.

    1999-02-01

    After a primary infection, herpes simplex virus is maintained in a latent state in neurons of sensory ganglia until complex stimuli reactivate viral lytic replication. Although the mechanisms governing reactivation from the latent state remain unknown, the regulated expression of the viral immediate early genes represents a critical point in this process. These genes are controlled by transcription enhancer complexes whose assembly requires and is coordinated by the cellular C1 factor (host cell factor). In contrast to other tissues, the C1 factor is not detected in the nuclei of sensory neurons. Experimental conditions that induce the reactivation of herpes simplex virus in mouse model systems result in rapid nuclear localization of the protein, indicating that the C1 factor is sequestered in these cells until reactivation signals induce a redistribution of the protein. The regulated localization suggests that C1 is a critical switch determinant of the viral lytic-latent cycle.

  6. 2012 Problem 15: Frustrating Golf Ball

    NASA Astrophysics Data System (ADS)

    Huang, Shan; Zhu, Zheyuan; Gao, Wenli; Wang, Sihui

    2015-10-01

    This paper studies the condition for a golf ball to escape from a hole. The two determining factors are the ball's initial velocity v0 and its deviation from the center of the hole d. There is a critical escaping velocity vc for every deviation d. The ball's motion is analyzed by calculating the change of velocity whenever the ball collides with the hole. The critical conditions predicted by our theory are verified through experiment.

  7. Direct URCA process in neutron stars

    NASA Technical Reports Server (NTRS)

    Lattimer, James M.; Prakash, Madappa; Pethick, C. J.; Haensel, Pawel

    1991-01-01

    It is shown that the direct URCA process can occur in neutron stars if the proton concentration exceeds some critical value in the range 11-15 percent. The proton concentration, which is determined by the poorly known symmetry energy of matter above nuclear density, exceeds the critical value in many current calculations. If it occurs, the direct URCA process enhances neutrino emission and neutron star cooling rates by a large factor compared to any process considered previously.

  8. The physiological determinants of Sudden Infant Death Syndrome☆,☆☆

    PubMed Central

    Garcia, Alfredo J.; Koschnitzky, Jenna E.; Ramirez, Jan-Marino

    2013-01-01

    It is well-established that environmental and biological risk factors contribute to Sudden Infant Death Syndrome (SIDS). There is also growing consensus that SIDS requires the intersection of multiple risk factors that result in the failure of an infant to overcome cardio-respiratory challenges. Thus, the critical next steps in understanding SIDS are to unravel the physiological determinants that actually cause the sudden death, to synthesize how these determinants are affected by the known risk factors, and to develop novel ideas for SIDS prevention. In this review, we will examine current and emerging perspectives related to cardio-respiratory dysfunctions in SIDS. Specifically, we will review: (1) the role of the preBötzinger complex (preBötC) as a multi-functional network that is critically involved in the failure to adequately respond to hypoxic and hypercapnic challenges; (2) the potential involvement of the pre-BötC in the gender and age distributions that are characteristic for SIDS; (3) the link between SIDS and prematurity; and (4) the potential relationship between SIDS, auditory function, and central chemosensitivity. Each section underscores the importance of marrying the epidemiological and pathological data to experimental data in order to understand the physiological determinants of this syndrome. We hope that a better understanding will lead to novel ways to reduce the risk to succumb to SIDS. PMID:23735486

  9. McMurdo LTER: streamflow measurements in Taylor Valley

    USGS Publications Warehouse

    McKnight, D.; House, H.; Von Guerard, P.

    1994-01-01

    Has established a stream gaging network for the three major lake basins in Taylor Valley. These data are critical for determining nutrient budgets for the lake ecosystems and for understanding physical factors controlling microbial mats in the streams.

  10. The Social Determinants of Refugee Mental Health in the Post-Migration Context: A Critical Review.

    PubMed

    Hynie, Michaela

    2018-05-01

    With the global increase in the number of refugees and asylum seekers, mental health professionals have become more aware of the need to understand and respond to the mental health needs of forced migrants. This critical review summarizes the findings of recent systematic reviews and primary research on the impact of post-migration conditions on mental disorders and PTSD among refugees and asylum seekers. Historically, the focus of mental health research and interventions with these populations has been on the impact of pre-migration trauma. Pre-migration trauma does predict mental disorders and PTSD, but the post-migration context can be an equally powerful determinant of mental health. Moreover, post-migration factors may moderate the ability of refugees to recover from pre-migration trauma. The importance of post-migration stressors to refugee mental health suggests the need for therapeutic interventions with psychosocial elements that address the broader conditions of refugee and asylum seekers' lives. However, there are few studies of multimodal interventions with refugees, and even fewer with control conditions that allow for conclusions about their effectiveness. These findings are interpreted using a social determinants of health framework that connects the risk and protective factors in the material and social conditions of refugees' post-migration lives to broader social, economic and political factors.

  11. Determination of the dissipation in superconducting Josephson junctions

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

    Mugnai, D., E-mail: d.mugnai@ifac.cnr.it; Ranfagni, A.; Cacciari, I.

    2015-02-07

    The results relative to macroscopic quantum tunneling rate, out of the metastable state of Josephson junctions, are examined in view of determining the effect of dissipation. We adopt a simple criterion in accordance to which the effect of dissipation can be evaluated by analyzing the shortening of the semiclassical traversal time of the barrier. In almost all the considered cases, especially those with relatively large capacitance values, the relative time shortening turns out to be about 20% and with a corresponding quality factor Q ≃ 5.5. However, beyond the specific cases here considered, still in the regime of moderate dissipation,more » the method is applicable also to different situations with different values of the quality factor. The method allows, within the error limits, for a reliable determination of the load resistance R{sub L}, the less accessible quantity in the framework of the resistively and capacitively shunted junction model, provided that the characteristics of the junction (intrinsic capacitance, critical current, and the ratio of the bias current to the critical one) are known with sufficient accuracy.« less

  12. FACTORS AFFECTING AIR EXCHANGE IN TWO HOUSES

    EPA Science Inventory

    Air exchange rate is critical to determining the relationship between indoor and outdoor concentrations of hazardous pollutants. Approximately 150 air exchange experiments were completed in two residences: a two-story detached house located in Redwood City, CA and a three-story...

  13. Critical Success Factor for Implementing Vocational Blended Learning

    NASA Astrophysics Data System (ADS)

    Dewi, K. C.; Ciptayani, P. I.; Surjono, H. D.; Priyanto

    2018-01-01

    Blended learning provides many benefits to the flexibility of time, place and situation constraints. The research’s objectives was describing the factors that determine the successful implementation of blended learning in vocational higher education. The research used a qualitative approach, data collected through observations and interviews by questionnare based on the CSFs indicators refers to TAM and Kliger. Data analysis was inductive method. The result provided an illustration that the success of vocational blended learning implementation was largely determined by the selection of instructional models that are inline with learning achievement target. The effectiveness of blended learning required the existence of policy support, readiness of IT infrastructure. Changing lecturer’s culture by utilizing ICT can also encourage the accelerated process of successful implementation. It can concluded that determinant factor of successful implementation of blended learning in vocational education is determined by teacher’s ability in mastering the pedagogical knowledge of designing instructional models.

  14. Approach for validating actinide and fission product compositions for burnup credit criticality safety analyses

    DOE PAGES

    Radulescu, Georgeta; Gauld, Ian C.; Ilas, Germina; ...

    2014-11-01

    This paper describes a depletion code validation approach for criticality safety analysis using burnup credit for actinide and fission product nuclides in spent nuclear fuel (SNF) compositions. The technical basis for determining the uncertainties in the calculated nuclide concentrations is comparison of calculations to available measurements obtained from destructive radiochemical assay of SNF samples. Probability distributions developed for the uncertainties in the calculated nuclide concentrations were applied to the SNF compositions of a criticality safety analysis model by the use of a Monte Carlo uncertainty sampling method to determine bias and bias uncertainty in effective neutron multiplication factor. Application ofmore » the Monte Carlo uncertainty sampling approach is demonstrated for representative criticality safety analysis models of pressurized water reactor spent fuel pool storage racks and transportation packages using burnup-dependent nuclide concentrations calculated with SCALE 6.1 and the ENDF/B-VII nuclear data. Furthermore, the validation approach and results support a recent revision of the U.S. Nuclear Regulatory Commission Interim Staff Guidance 8.« less

  15. Testing glueline continuity in standard-size hardwood blanks by mechanical methods

    Treesearch

    David W. Patterson; Nathan D. Hesterman; Charles Gatchell

    1991-01-01

    Glueline continuity is very critical in standard-size hardwood blanks because the blanks are cut up into small furniture parts, and a small gap in the glueline of a blank may extend across the whole part—or a gap may appear as a crack in the final product. Strength is not a critical factor. The objective of this study was to determine if a gap in a glueline can be...

  16. Hypophosphatemia in Critically Ill Children: Risk Factors, Outcome and Mechanism.

    PubMed

    Shah, Satish Kumar; Irshad, Mohammad; Gupta, Nandita; Kabra, Sushil Kumar; Lodha, Rakesh

    2016-11-01

    To determine the prevalence of hypophosphatemia in critically ill children and its association with clinical outcomes; to determine risk factors and mechanism of hypophosphatemia. Levels of serum phosphate, phosphate intake, renal phosphate handling indices and blood gases were measured on days 1, 3, 7 and 10 of pediatric intensive care unit (PICU) stay. Hypophosphatemia was defined as any serum phosphorus <3.8 mg/dl for children younger than 2 y and <3.5 mg/dl for children 2 y or older. Renal phosphate loss was assessed using the ratio of tubular maximum reabsorption of phosphate (TmP) to glomerular filtration rate (GFR) [TmP/GFR]. Prevalence of hypophosphatemia was 71.6 % (95 % CI: 64.6-78.6). On adjusted analysis, hypophosphatemia was associated with prolonged PICU length of stay (PICU LOS > 6 d) (adjusted OR: 3.0 [95 % CI: 1.4-6.7; p = 0.005]) but not associated with increased mortality. Renal phosphate threshold was significantly lower on all the days in hypophosphatemic group compared to that of non-hypophosphatemic group. No statistically significant difference in the amount of phosphate intake was seen in both the groups. Hypophosphatemia is highly prevalent in critically ill children and is associated with prolonged PICU LOS. Increased phosphate loss in urine is one of the mechanism responsible for hypophosphatemia in critically ill children.

  17. Factors Affecting Resilience and Development of Posttraumatic Stress Disorder in Critical Care Nurses.

    PubMed

    Mealer, Meredith; Jones, Jacqueline; Meek, Paula

    2017-05-01

    Job stress and cumulative exposure to traumatic events experienced by critical care nurses can lead to psychological distress and the development of burnout syndrome and posttraumatic stress disorder. Resilience can mitigate symptoms associated with these conditions. To identify factors that affect resilience and to determine if the factors have direct or indirect effects on resilience in development of posttraumatic stress disorder. Data from 744 respondents to a survey mailed to 3500 critical care nurses who were members of the American Association of Critical-Care Nurses were analyzed. Mplus was used to analyze a mediation model. Nurses who worked in any type of intensive care unit other than the medical unit and had high scores for resilience were 18% to 50% less likely to experience post-traumatic stress disorder than were nurses with low scores. Nurses with a graduate degree in nursing were 18% more likely to experience posttraumatic stress disorder than were nurses with a bachelor's degree. Because of their effects on resilience, working in a medical intensive care unit and having a graduate degree may influence the development of posttraumatic stress disorder. Future research is needed to better understand the impact of resilience on health care organizations, development of preventive therapies and treatment of posttraumatic stress disorder for critical care nurses, and the most appropriate mechanism to disseminate and implement strategies to address posttraumatic stress disorder. ©2017 American Association of Critical-Care Nurses.

  18. Probing quantum frustrated systems via factorization of the ground state.

    PubMed

    Giampaolo, Salvatore M; Adesso, Gerardo; Illuminati, Fabrizio

    2010-05-21

    The existence of definite orders in frustrated quantum systems is related rigorously to the occurrence of fully factorized ground states below a threshold value of the frustration. Ground-state separability thus provides a natural measure of frustration: strongly frustrated systems are those that cannot accommodate for classical-like solutions. The exact form of the factorized ground states and the critical frustration are determined for various classes of nonexactly solvable spin models with different spatial ranges of the interactions. For weak frustration, the existence of disentangling transitions determines the range of applicability of mean-field descriptions in biological and physical problems such as stochastic gene expression and the stability of long-period modulated structures.

  19. Peer Led Team Learning in Introductory Biology: Effects on Peer Leader Critical Thinking Skills

    PubMed Central

    Snyder, Julia J.; Wiles, Jason R.

    2015-01-01

    This study evaluated hypothesized effects of the Peer-Led Team Learning (PLTL) instructional model on undergraduate peer leaders’ critical thinking skills. This investigation also explored peer leaders’ perceptions of their critical thinking skills. A quasi-experimental pre-test/post-test with control group design was used to determine critical thinking gains in PLTL/non-PLTL groups. Critical thinking was assessed using the California Critical Thinking Skills Test (CCTST) among participants who had previously completed and been successful in a mixed-majors introductory biology course at a large, private research university in the American Northeast. Qualitative data from open-ended questionnaires confirmed that factors thought to improve critical thinking skills such as interaction with peers, problem solving, and discussion were perceived by participants to have an impact on critical thinking gains. However, no significant quantitative differences in peer leaders’ critical thinking skills were found between pre- and post-experience CCTST measurements or between experimental and control groups. PMID:25629311

  20. Peer led team learning in introductory biology: effects on peer leader critical thinking skills.

    PubMed

    Snyder, Julia J; Wiles, Jason R

    2015-01-01

    This study evaluated hypothesized effects of the Peer-Led Team Learning (PLTL) instructional model on undergraduate peer leaders' critical thinking skills. This investigation also explored peer leaders' perceptions of their critical thinking skills. A quasi-experimental pre-test/post-test with control group design was used to determine critical thinking gains in PLTL/non-PLTL groups. Critical thinking was assessed using the California Critical Thinking Skills Test (CCTST) among participants who had previously completed and been successful in a mixed-majors introductory biology course at a large, private research university in the American Northeast. Qualitative data from open-ended questionnaires confirmed that factors thought to improve critical thinking skills such as interaction with peers, problem solving, and discussion were perceived by participants to have an impact on critical thinking gains. However, no significant quantitative differences in peer leaders' critical thinking skills were found between pre- and post-experience CCTST measurements or between experimental and control groups.

  1. CELLULAR AND MOLECULAR MECHANISMS OF ABNORMAL REPRODUCTIVE DEVELOPMENT

    EPA Science Inventory

    This project will determine the critical factors that account for exposures to endocrine disrupting chemicals, or EDCs (ER, AR, AhR mediated and inhibitors of steroidogenesis) during development resulting in adverse effects seen later in life in male and female offspring. Such f...

  2. 511, America's traveler information number. Deployment assistance report #1, Business models and cost considerations

    DOT National Transportation Integrated Search

    2002-01-01

    Business models and cost recovery are the critical factors for determining the sustainability of the traveler information service, and 511. In March 2001 the Policy Committee directed the 511 Working Group to investigate plausible business models and...

  3. HIV INFECTION AMONG FEMALE SEX WORKERS IN CONCENTRATED AND HIGH PREVALENCE EPIDEMICS: WHY A STRUCTURAL DETERMINANTS FRAMEWORK IS NEEDED

    PubMed Central

    Shannon, Kate; Goldenberg, Shira M.; Deering, Kathleen N.; Strathdee, Steffanie A.

    2014-01-01

    Purpose of review This article reviews the current state of the epidemiological literature on female sex work and HIV from the past 18 months. We offer a conceptual framework for structural HIV determinants and sex work that unpacks intersecting structural, interpersonal, and individual biological and behavioural factors. Recent findings Our review suggests that despite the heavy HIV burden among female sex workers (FSWs) globally, data on the structural determinants shaping HIV transmission dynamics have only begun to emerge. Emerging research suggests that factors operating at macrostructural (e.g., migration, stigma, criminalized laws), community organization (e.g., empowerment) and work environment levels (e.g., violence, policing, access to condoms HIV testing, HAART) act dynamically with interpersonal (e.g., dyad factors, sexual networks) and individual biological and behavioural factors to confer risks or protections for HIV transmission in female sex work. Summary Future research should be guided by a Structural HIV Determinants Framework to better elucidate the complex and iterative effects of structural determinants with interpersonal and individual biological and behavioural factors on HIV transmission pathways among FSWs, and meet critical gaps in optimal access to HIV prevention, treatment, and care for FSWs globally. PMID:24464089

  4. Heat Capacity Anomaly Near the Lower Critical Consolute Point of Triethylamine-Water

    NASA Technical Reports Server (NTRS)

    Flewelling, Anne C.; DeFonseka, Rohan J.; Khaleeli, Nikfar; Partee, J.; Jacobs, D. T.

    1996-01-01

    The heat capacity of the binary liquid mixture triethylamine-water has been measured near its lower critical consolute point using a scanning, adiabatic calorimeter. Two data runs are analyzed to provide heat capacity and enthalpy data that are fitted by equations with background terms and a critical term that includes correction to scaling. The critical exponent a was determined to be 0.107 +/- 0.006, consistent with theoretical predictions. When alpha was fixed at 0.11 to determine various amplitudes consistently, our values of A(+) and A(-) agreed with a previous heat capacity measurement, but the value of A(-) was inconsistent with values determined by density or refractive index measurements. While our value for the amplitude ratio A(+)/ A(-) = 0.56 +/- 0.02 was consistent with other recent experimental determinations in binary liquid mixtures, it was slightly larger than either theoretical predictions or recent experimental values in liquid-vapor systems. The correction to scaling amplitude ratio D(+)/D(-) = 0.5 +/- 0.1 was half of that predicted. As a result of several more precise theoretical calculations and experimental determinations, the two-scale-factor universality ratio X, which we found to be 0.019 +/- 0.003, now is consistent among experiments and theories. A new 'universal' amplitude ratio R(sup +/-)(sub Bcr) involving the amplitudes for the specific heat was tested. Our determination of R(sup +/-)(sub Bcr) = -0.5 +/- 0.1 and R(sup -)(sub Bcr) = 1.1 +/- 0.1 is smaller in magnitude than predicted and is the first such determination in a binary fluid mixture.

  5. An Illumination Modeling System for Human Factors Analyses

    NASA Technical Reports Server (NTRS)

    Huynh, Thong; Maida, James C.; Bond, Robert L. (Technical Monitor)

    2002-01-01

    Seeing is critical to human performance. Lighting is critical for seeing. Therefore, lighting is critical to human performance. This is common sense, and here on earth, it is easily taken for granted. However, on orbit, because the sun will rise or set every 45 minutes on average, humans working in space must cope with extremely dynamic lighting conditions. Contrast conditions of harsh shadowing and glare is also severe. The prediction of lighting conditions for critical operations is essential. Crew training can factor lighting into the lesson plans when necessary. Mission planners can determine whether low-light video cameras are required or whether additional luminaires need to be flown. The optimization of the quantity and quality of light is needed because of the effects on crew safety, on electrical power and on equipment maintainability. To address all of these issues, an illumination modeling system has been developed by the Graphics Research and Analyses Facility (GRAF) and Lighting Environment Test Facility (LETF) in the Space Human Factors Laboratory at NASA Johnson Space Center. The system uses physically based ray tracing software (Radiance) developed at Lawrence Berkeley Laboratories, a human factors oriented geometric modeling system (PLAID) and an extensive database of humans and environments. Material reflectivity properties of major surfaces and critical surfaces are measured using a gonio-reflectometer. Luminaires (lights) are measured for beam spread distribution, color and intensity. Video camera performances are measured for color and light sensitivity. 3D geometric models of humans and the environment are combined with the material and light models to form a system capable of predicting lighting conditions and visibility conditions in space.

  6. Analysis of Critical Mass in Threshold Model of Diffusion

    NASA Astrophysics Data System (ADS)

    Kim, Jeehong; Hur, Wonchang; Kang, Suk-Ho

    2012-04-01

    Why does diffusion sometimes show cascade phenomena but at other times is impeded? In addressing this question, we considered a threshold model of diffusion, focusing on the formation of a critical mass, which enables diffusion to be self-sustaining. Performing an agent-based simulation, we found that the diffusion model produces only two outcomes: Almost perfect adoption or relatively few adoptions. In order to explain the difference, we considered the various properties of network structures and found that the manner in which thresholds are arrayed over a network is the most critical factor determining the size of a cascade. On the basis of the results, we derived a threshold arrangement method effective for generation of a critical mass and calculated the size required for perfect adoption.

  7. Safety in the operating theatre--part 1: interpersonal relationships and team performance

    NASA Technical Reports Server (NTRS)

    Schaefer, H. G.; Helmreich, R. L.; Scheidegger, D.

    1995-01-01

    The authors examine the application of interpersonal human factors training on operating room (OR) personnel. Mortality studies of OR deaths and critical incident studies of anesthesia are examined to determine the role of human error in OR incidents. Theoretical models of system vulnerability to accidents are presented with emphasis on a systems approach to OR performance. Input, process, and outcome factors are discussed in detail.

  8. Thermophilic treatment of acidified and partially acidified wastewater using an anaerobic submerged MBR: Factors affecting long-term operational flux.

    PubMed

    Jeison, D; van Lier, J B

    2007-09-01

    The long-term operation of two thermophilic anaerobic submerged membrane bioreactors (AnSMBRs) was studied using acidified and partially acidified synthetic wastewaters. In both reactors, cake formation was identified as the key factor governing critical flux. Even though cake formation was observed to be mostly reversible, particle deposition proceeds fast once the critical flux is exceeded. Very little irreversible fouling was observed during long-term operation, irrespective of the substrate. Critical flux values at the end of the reactors operation were 7 and 3L/m(2)h for the AnSMBRs fed with acidified and partially acidified wastewaters, respectively, at a gas superficial velocity of 70m/h. Small particle size was identified as the responsible parameter for the low observed critical flux values. The degree of wastewater acidification significantly affected the physical properties of the sludge, determining the attainable flux. Based on the fluxes observed in this research, the membrane costs would be in the range of 0.5euro/m(3) of treated wastewater. Gas sparging was ineffective in increasing the critical flux values. However, preliminary tests showed that cross-flow operation may be a feasible alternative to reduce particle deposition.

  9. NASA's Functional Task Test: Informing the Design of an Integrated Countermeasure System

    NASA Technical Reports Server (NTRS)

    Bloomberg, J. J.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Laurie, S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.; hide

    2015-01-01

    The goals of the Functional Task Test (FTT) study were to determine the effects of spaceflight on functional tests that are representative of critical exploration mission tasks and to identify the key physiological factors that contribute to decrements in performance.

  10. Prevention in Mental Health: Organizational and Ideological Perspectives.

    ERIC Educational Resources Information Center

    Walsh, Joseph A.

    1982-01-01

    Studied 33 community mental health centers to determine what types of organizational variables and ideological factors might affect whether a community health center conducted prevention programs. Results indicated organizational support and ideological support of mental health professionals were critical variables for prevention programs.…

  11. Estimating winter wheat phenological parameters: Implications for crop modeling

    USDA-ARS?s Scientific Manuscript database

    Crop parameters, such as the timing of developmental events, are critical for accurate simulation results in crop simulation models, yet uncertainty often exists in determining the parameters. Factors contributing to the uncertainty include: a) sources of variation within a plant (i.e., within diffe...

  12. The relationship of educational preparation, autonomy, and critical thinking to nursing job satisfaction.

    PubMed

    Zurmehly, Joyce

    2008-10-01

    This descriptive correlational study explored factors influencing job satisfaction in nursing. Relationships between educational preparation, autonomy, and critical thinking and job satisfaction were examined. A convenience sample of 140 registered nurses was drawn from medical-surgical, management, and home health nursing specialties. The nurses were asked to complete the Watson-Glaser Critical Thinking Appraisal and Minnesota Satisfaction Questionnaire. Relationships between variables were analyzed to determine which explained the most variance in job satisfaction. Results indicated significant positive correlations between total job satisfaction and perceived autonomy, critical thinking, educational preparation, and job satisfiers. Significant negative correlations between job dissatisfiers and total job satisfaction were also found. Understanding nursing job satisfaction through critical thinking, educational level, and autonomy is the key to staff retention. Further research focusing on increasing these satisfiers is needed.

  13. Development and Psychometric Properties of the Nursing Critical Thinking in Clinical Practice Questionnaire.

    PubMed

    Zuriguel-Pérez, Esperanza; Falcó-Pegueroles, Anna; Roldán-Merino, Juan; Agustino-Rodriguez, Sandra; Gómez-Martín, Maria Del Carmen; Lluch-Canut, Maria Teresa

    2017-08-01

    A complex healthcare environment, with greater need for care based on the patient and evidence-based practice, are factors that have contributed to the increased need for critical thinking in professional competence. At the theoretical level, Alfaro-LeFevre () put forward a model of critical thinking made up of four components. And although these explain the construct, instruments for their empirical measurement are lacking. The purpose of the study was to develop and validate the psychometric properties of an instrument, the Nursing Critical Thinking in Clinical Practice Questionnaire (N-CT-4 Practice), designed to evaluate the critical thinking abilities of nurses in the clinical setting. A cross-sectional survey design was used. A pool of items was generated for evaluation by a panel of experts who considered their validity for the new instrument, which was finally made up of 109 items. Following this, validation was carried out using a sample of 339 nurses at a hospital in Barcelona, Spain. Reliability was determined by means of internal consistency and test-retest stability over time, although the validity of the construct was assessed by means of confirmatory factor analysis. The content validity index of the N-CT-4 Practice was .85. Cronbach's alpha coefficient for the whole instrument was .96. The intraclass correlation coefficient was .77. Confirmatory factor analysis showed that the instrument was in line with the four-dimensional model proposed by Alfaro-LeFevre (). The psychometric properties of theN-CT-4 Practice uphold its potential for use in measuring critical thinking and in future research related with the examination of critical thinking. © 2017 The Authors Worldviews on Evidence-Based Nursing published by Wiley Periodicals, Inc. on behalf of Sigma Theta Tau International The Honor Society of Nursing.

  14. Learning to account for the social determinants of health affecting homeless persons.

    PubMed

    McNeil, Ryan; Guirguis-Younger, Manal; Dilley, Laura B; Turnbull, Jeffrey; Hwang, Stephen W

    2013-05-01

    Intersecting social determinants of health constrain access to care and treatment adherence among homeless populations. Because clinicians seldom receive training in the social determinants of health, they may be unprepared to account for or address these factors when developing treatment strategies for homeless individuals. This study explored: (i) clinicians' preparedness to provide care responsive to the social determinants of health in homeless populations, and (ii) the steps taken by clinicians to overcome shortcomings in their clinical training in regard to the social determinants of health. Qualitative interviews were conducted with doctors (n = 6) and nurses (n = 18) in six Canadian cities. Participants had at least 2 years of experience in providing care to homeless populations. Interview transcripts were analysed using methods of constant comparison. Participants highlighted how, when first providing care to this population, they were unprepared to account for or address social determinants shaping the health of homeless persons. However, participants recognised the necessity of addressing these factors to situate care within the social and structural contexts of homelessness. Participants' accounts illustrated that experiential learning was critical to increasing capacity to provide care responsive to the social determinants of health. Experiential learning was a continuous process that involved: (i) engaging with homeless persons in multiple settings and contexts to inform treatment strategies; (ii) evaluating the efficacy of treatment strategies through continued observation and critical reflection, and (iii) adjusting clinical practice to reflect observations and new knowledge. This study underscores the need for greater emphasis on the social determinants of health in medical education in the context of homelessness. These insights may help to inform the development and design of service-learning initiatives that integrate understandings of the social determinants of health, and thus potentially improve the readiness of clinicians to address the complex factors that shape the health of homeless populations. © Blackwell Publishing Ltd 2013.

  15. Adverse outcomes in maternity care for women with a low risk profile in The Netherlands: a case series analysis

    PubMed Central

    2013-01-01

    Background This study aimed to perform a structural analysis of determinants of risk of critical incidents in care for women with a low risk profile at the start of pregnancy with a view on improving patient safety. Methods We included 71 critical incidents in primary midwifery care and subsequent hospital care in case of referral after 36 weeks of pregnancy that were related to substandard care and for that reason were reported to the Health Care Inspectorate in The Netherlands in 36 months (n = 357). We performed a case-by-case analysis, using a previously validated instrument which covered five broad domains: healthcare organization, communication between healthcare providers, patient risk factors, clinical management, and clinical outcomes. Results Determinants that were associated with risk concerned healthcare organization (n = 20 incidents), communication about treatment procedures (n = 39), referral processes (n = 19), risk assessment by telephone triage (n = 10), and clinical management in an out of hours setting (n = 19). The 71 critical incidents included three cases of maternal death, eight cases of severe maternal morbidity, 42 perinatal deaths and 12 critical incidents with severe morbidity for the child. Suboptimal prenatal risk assessment, a delay in availability of health care providers in urgent situations, miscommunication about treatment between care providers, and miscommunication with patients in situations with a language barrier were associated with safety risks. Conclusions Systematic analysis of critical incidents improves insight in determinants of safety risk. The wide variety of determinants of risk of critical incidents implies that there is no single intervention to improve patient safety in the care for pregnant women with initially a low risk profile. PMID:24286376

  16. Psychometric properties of the Persian version of the Intensive and Critical Care Nursing Competence Scale version-1 (ICCN-CS-1).

    PubMed

    Shouryabi, Ali Asghar; Ghahrisarabi, Alireza; Anboohi, Sima Zohari; Nasiri, Malihe; Rassouli, Maryam

    2017-11-01

    Nursing competence is highly related to patient outcomes and patient safety issues, especially in intensive care units. Competence assessment tools are needed specifically for intensive care nursing. This study was performed to determine psychometric properties of the Intensive and Critical Care Nursing Competence Scale version-1 between Iranian Nurses. The present study was a methodological research in which 289 nurses of Intensive Care Units from nine hospitals in Shahid Beheshti University of Medical Sciences in Tehran were selected between 2015 and 2016. The original version of the scale was translated into Persian and back-translated into English, and the comments of the developer were applied. The validity of the scale was the determined quality (content validity and face validity) and quantity (confirmatory factor analysis). Reliability of the scale was reported by Cronbach's alpha coefficient and Intra class Correlation Coefficient. SPSS-PC (v.21) and LISREL (v.8.5) were used to analyze the data. The intensive and critical care nursing competence scale version-1 is a self-assessment test that consists of 144 items and four domains which are the knowledge base, the skill base, the attitudes and values base and the experience base, which are divided into clinical competence and professional competence. Content and face validity was confirmed by 10 experts and 10 practitioner nurses in the intensive care units. In confirmatory factor analysis, all fitness indexes, except goodness of fit index (0.64), confirmed the four-factor structure of the ICCN-CS-1. The results of the factor analysis, load factor between 0.304 and 0.727 items was estimated; only 4 items out of 144 items, that were loaded were less than 0.3 due to high Cronbach's alpha coefficient (0.984-0.986), all items were preserved, no item was removed and 4 subscales of the original scale were confirmed. The results of this study indicated that the Persian version of "The Intensive and Critical Care Nursing Competence Scale version-1" is a valid and reliable scale for the assessment of competency among Iranian nurses, and it can be used as a reliable scale in nursing management, education and research.

  17. Review of critical factors for SEA implementation

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

    Zhang Jie, E-mail: jasmine@plan.aau.dk; Christensen, Per; Kornov, Lone

    The implementation process involved in translating Strategic Environmental Assessment (SEA) intention into action is vital to an effective SEA. Many factors influence implementation and thus the effectiveness of an SEA. Empirical studies have identified and documented some factors influencing the implementation of an SEA. This research is fragmented, however, and it is still not clear what are the most critical factors of effective SEA performance, and how these relate to different stages of the implementation process or other contextual circumstances. The paper takes its point of departure in implementation theory. Firstly, we introduce implementation theory, and then use it inmore » practice to establish a more comprehensive model related to the stages in the implementation process. Secondly, we identify the critical factors in order to see how they are related to the different stages of SEA or are more general in character. Finally we map the different critical factors and how they influence the overall results of an SEA. Based on a literature review, we present a comprehensive picture of the critical factors and where they are found in the process. We conclude that most of the critical factors identified are of a more general character influencing the SEA process as such, while only one out of four of these factors relates to the specific stages of the SEA. Based on this mapping we can sketch a picture of the totality of critical factors. In this study 266 notions of critical factors were identified. Seen at the level of notions of critical factors, only 24% of these relate to specific stages while for 76% the critical factors are of a more general nature. These critical factors interact in complex ways and appear in different combinations in different stages of the implementation process so tracing the cause and effect is difficult. The pervasiveness of contextual and general factors also clearly suggests that there is no single way to put SEA into practice. The paper identifies some of the critical factors for effective SEA implementation, but further research is still needed to conclude which factors are more critical than others, just as the contingencies on which they depend are not easy to unravel. - Highlights: Black-Right-Pointing-Pointer The research on critical factors influencing SEA implementation is fragmented. Black-Right-Pointing-Pointer The critical factors are used to discuss 'hot-spots' in the implementation process. Black-Right-Pointing-Pointer Critical factors are just as broad as the concept of effectiveness. Black-Right-Pointing-Pointer Both stage and general factors are relevant in explaining the effectiveness of SEA.« less

  18. Evaluation of carotenoids and reactive oxygen species in human skin after UV irradiation: a critical comparison between in vivo and ex vivo investigations.

    PubMed

    Meinke, Martina C; Müller, Robert; Bechtel, Anne; Haag, Stefan F; Darvin, Maxim E; Lohan, Silke B; Ismaeel, Fakher; Lademann, Jürgen

    2015-03-01

    UV irradiation is one of the most harmful exogenous factors for the human skin. In addition to the development of erythema, free radicals, that is reactive oxygen species (ROS), are induced under its influence and promote the development of oxidative stress in the skin. Several techniques are available for determining the effect of UV irradiation. Resonance Raman spectroscopy (RRS) measures the reduction of the carotenoid concentration, while electron paramagnetic resonance (EPR) spectroscopy enables the analysis of the production of free radicals. Depending on the method, the skin parameters are analysed in vivo or ex vivo. This study provides a critical comparison between in vivo and ex vivo investigations on the ROS formation and carotenoid depletion caused by UV irradiation in human skin. The oxygen content of tissue was also determined. It was shown that the antioxidant status measured in the skin samples in vivo and ex vivo was different. The depletion in the carotenoid concentration in vivo exceeded the value determined ex vivo by a factor of about 1.5, and the radical formation after UV irradiation was significantly greater in vivo by a factor of 3.5 than that measured in excised human skin, which can be explained by the lack of oxygen ex vivo. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. NREL, University of Texas Scientists Determine Critical Factor for

    Science.gov Websites

    technology closer to commercialization. The research was conducted by scientists at the Department of of Organic-Inorganic Trihalide Perovskites," outlined the first quantitative nanoscale more easily manufactured and at a lower cost than silicon solar cells. Ongoing research, including at

  20. Consideration of Alternative Educational Systems.

    ERIC Educational Resources Information Center

    McFann, Howard H.; And Others

    A discussion of factors associated with evaluation of proposed alternative educational systems is presented in brief form. Emphasis is given to enumeration of critical characteristics serving as the basis of comparison, examination of alternative systems in terms of each characteristic, and determination based on the comparison as to whether the…

  1. Soil ingestion rates for children under 3 years old in Taiwan

    EPA Science Inventory

    Soil and dust ingestion rates by children are among the most critical exposure factors in determining risks to children from exposures to environmental contaminants in soil and dust. This is the first published soil ingestion study for children in Taiwan using tracer element meth...

  2. Cardio-respiratory Outcomes Associated with Exposure to Wildfire Smoke are Modified by Measures of Community Health

    EPA Science Inventory

    Background: Characterizing factors which determine susceptibility to air pollution is an important step in understanding the distribution of risk in a population and is a critical for setting appropriate air quality management policies. Objective: To evaluate general and specif...

  3. Caring at home until death: enabled determination.

    PubMed

    Robinson, Carole A; Bottorff, Joan L; McFee, Erin; Bissell, Laura J; Fyles, Gillian

    2017-04-01

    The importance of family caregivers in providing palliative care at home and in supporting a home death is well supported. Gaining a better understanding of what enables palliative family caregivers to continue caring at home for their family members until death is critical to providing direction for more effective support. The purpose of the study was to describe the experiences of bereaved family caregivers whose terminally ill family members with advanced cancer were successful in achieving a desired home death. A qualitative interpretive descriptive approach was used. Data were collected using semi-structured, audio-recorded interviews conducted in-person or via telephone in addition to field notes and reflective journaling. The study took place in British Columbia, Canada, and included 29 bereaved adult family caregivers who had provided care for a family member with advanced cancer and experienced a home death. Four themes captured the experience of caring at home until death: context of providing care, supportive antecedents to providing care, determination to provide care at home, and enabled determination. Factors that enabled determination to achieve a home death included initiation of formal palliative care, asking for and receiving help, augmented care, relief or respite, and making the healthcare system work for the ill person. Clarifying caregiving goals and supporting the factors that enable caregiver determination appear to be critical in enhancing the likelihood of a desired home death.

  4. Anaerobic wastewater treatment and membrane filtration: a one night stand or a sustainable relationship?

    PubMed

    Jeison, D; van Lier, J B

    2008-01-01

    Several anaerobic membrane bioreactors (AnMBR) were operated, under various conditions, applying different reactor configurations. Applicable fluxes were strongly determined by the physical properties of the sludge present in the reactors. Results show that particle size is a key determining factor for the attainable fluxes. Under thermophilic conditions, small sludge particle size was observed, resulting in low critical fluxes reaching 6-7 L/m2h for the submerged configuration and acidified substrate. In contrast, under mesophilic conditions critical fluxes of 20 L/m2h were obtained. The acidification level also showed a strong effect. Under thermophilic conditions, the presence of a significant fraction of non-acidified organic matter induced the growth of suspended acidogenic biomass that seriously affected the applicable fluxes, both in submerged and side-stream configurations. Under all conditions tested cake formation showed to be the limiting factor determining the applicable fluxes. Only low levels of irreversible fouling were observed. Due to technical and economical considerations, most interesting perspectives for the application of AnMBR are expected with the treatment of high-strength particulate wastewaters, and with extreme wastewaters characterised by high temperature, salinity, etc.

  5. Who should be responsible for supporting individuals with mental health problems? A critical literature review.

    PubMed

    Pope, Megan A; Malla, Ashok K; Iyer, Srividya N

    2018-05-01

    Individuals with mental health problems have many support needs that are often inadequately met; however, perceptions of who should be responsible for meeting these needs have been largely unexplored. Varying perceptions may influence whether, how, and to what extent relevant stakeholders support individuals with mental health problems. To critically evaluate the literature to determine who different stakeholders believe should be responsible for supporting individuals with mental health problems, what factors shape these perceptions, and how they relate to one another. A critical literature review was undertaken. Following an extensive literature search, the conceptual contributions of relevant works were critically evaluated. A concept map was created to build a conceptual framework of the topic. Views of individual versus societal responsibility for need provision and health; the morality of caring; and attributions of responsibility for mental illness offered valuable understandings of the review questions. Creating a concept map revealed that various interrelated factors may influence perceptions of responsibility. Varying perceptions of who should be responsible for supporting individuals with mental health problems may contribute to unmet support needs among this group. Our critical review helps build a much-needed conceptual framework of factors influencing perceptions of responsibility. Such a framework is essential as these views iteratively shape and reflect the complex divisions of mental healthcare roles and responsibilities. Understanding these perceptions can help define relevant stakeholders' roles more clearly, which can improve mental health services and strengthen stakeholder accountability.

  6. Unplanned extubations in an intensive care unit: Findings from a critical incident technique.

    PubMed

    Danielis, Matteo; Chiaruttini, Simona; Palese, Alvisa

    2018-05-15

    Patients on mechanical ventilation are at risk of experiencing a potentially life-threatening unplanned extubation in the intensive care unit, which can lead to arrhythmias, bronchial aspiration, difficulty in reintubation or even sudden cardiac arrest. Although incidence and outcomes of the phenomenon have been documented in several quantitative studies, no studies have investigated the antecedents as experienced by critical care nurses. To gain a greater understanding of the antecedents of unplanned extubations. A qualitative study design involving the critical-incident technique. A total of 10 registered nurses who reported one or more episodes of unplanned extubations were involved in an in-depth interview. According to the nurses' experience, episodes of unplanned extubations are determined by predisposing, precipitating and mediating factors. The predisposing factors have been recognised in the (a) weaning programme (expected/unexpected decreased sedation) and in the (b) patient factors (increased needs due to discomfort, restlessness and desire to communicate). The precipitating factors have been divided into (a) organisational (failures in multi-professional communication), (b) environmental (excessive environmental chaos and barriers preventing direct surveillance) and (c) nursing care factors (ensuring privacy by creating barriers, avoiding disturbing other patients and poor nurse-to-patient ratio). Among the mediating factors, which are affected by the precipitating factors, decreased surveillance and mechanical restraints' use have been identified. Identifying risk factors of unplanned extubation, specifically those that are modifiable, such as increasing interprofessional communication, reducing excessive environment chaos, implementing strategies aimed at overcoming barriers threatening direct surveillance and ensuring appropriate nurse-to-patient ratio, can prevent the occurrence of these events. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Problems and Trends Regarding Vocational Teachers in China

    ERIC Educational Resources Information Center

    Kuang, Ying

    2014-01-01

    At present, China's vocational education system is undergoing a transition process from growing in size to improving in quality. Teacher and teaching force issues are a bottleneck and critical factor that will determine whether the transformation will be successful. The real-world problems of the number, deployment, capacity, and training systems…

  8. The Development of After-School Program Educators through University-Community Partnerships

    ERIC Educational Resources Information Center

    Mahoney, Joseph L.; Levine, Mark D.; Hinga, Briana

    2010-01-01

    Participation in after-school programs (ASPs) "can" positively affect the development of young people. However, "whether" ASPs are beneficial depends on program quality. Although many factors influence the quality of a program, the competencies of adult staff who lead ASPs are a critical determinant. Unfortunately, ASP staff…

  9. Maternal nutrient restriction in early gestation upregulates myogenic genes in cattle fetal muscle tissue

    USDA-ARS?s Scientific Manuscript database

    Prenatal myogenesis is a critical factor in determining the muscle growth potential of cattle. We hypothesized that maternal nutrient restriction during early gestation would alter the transcriptome of fetal primordial muscle tissue in cattle. A total of 14 Angus-cross heifers were estrus synchroniz...

  10. Improving Outcomes for Workers with Mental Retardation

    ERIC Educational Resources Information Center

    Fornes, Sandra; Rocco, Tonette S.; Rosenberg, Howard

    2008-01-01

    This research presents an analysis of factors predicting job retention, job satisfaction, and job performance of workers with mental retardation. The findings highlight self-determination as a critical skill in predicting the three important employee outcomes. The study examined a hypothesized job retention model and the outcome of the three…

  11. NASA's Functional Task Test: Effects of Spaceflight and Six Degree Head-Down Bedrest on Dynamic Postural Stability

    NASA Technical Reports Server (NTRS)

    Taylor, L. C.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Laurie, S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Peters, B. T.; hide

    2015-01-01

    The goals of the Functional Task Test (FTT) study were to determine the effects of spaceflight on functional tests that are representative of critical exploration mission tasks and to identify the physiological factors that contribute to decrements in performance.

  12. Successful establishment of the invasive fire ant Solenopsis invicta in Taiwan: Insights into interactions of alternative social forms

    USDA-ARS?s Scientific Manuscript database

    Understanding the factors underlying the successful establishment of invasive ant species is critical for developing quarantine strategies to prevent additional invasions as well as for determining how such species overcome the selective pressures occurring in invaded areas. Although several studies...

  13. An Assessment of E-Training Effectiveness in Multinational Companies in Malaysia

    ERIC Educational Resources Information Center

    Ramayah, Thurasamy; Ahmad, Noor Hazlina; Hong, Tan Say

    2012-01-01

    E-training has developed into a revolutionary way of learning in Malaysian organizations due to rapid growth in information technology infrastructure. The present study endeavors to determine the critical factors that influence e-training effectiveness in multinational companies (MNCs) in Malaysia. By integrating Technology Acceptance Model (TAM),…

  14. Teacher Professional Development Strategies in Australian Government and Professional Associations Documents

    ERIC Educational Resources Information Center

    Kostina, Ludmyla

    2015-01-01

    Teacher in Australia is determined as an active participant of professional community with high level of collaboration, professional development coherent activities and collaborative learning practice. Thus, teacher quality is one of critical factors affecting student outcomes. The article touches upon the issue of the potential to improve…

  15. Feed efficiency - how should it be used for the cow herd?

    USDA-ARS?s Scientific Manuscript database

    In cows, the most critical factor influencing the output component of efficiency is reproductive rate, and not necessarily weight gain. Thus benefits of selecting animals with desirable measures of feed efficiency on cow efficiency remain to be determined. The feed input component of cow efficiency...

  16. Faculty Compensation Systems: Impact on the Quality of Higher Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Sutton, Terry P.; Bergerson, Peter J.

    Faculty compensation is a critical management tool for increasing faculty productivity, improving cost efficiency, and enhancing an institution's public image. Factors that determine faculty compensation include academic rank, faculty productivity, discipline market pay, ability to obtain external grants, seniority or length of service, service in…

  17. Research-Based Options for Education Policymaking: Preschool Education

    ERIC Educational Resources Information Center

    Mathis, William

    2012-01-01

    Publicly supported, high-quality preschool education is among the most successful and well-documented of education reforms. There is near-universal agreement that high-quality preschool programs more than pay for themselves in economic and social benefits. Program quality is absolutely critical. While no one factor can be considered determinative,…

  18. Determination of Critical Success Factors Affecting Mobile Learning: A Meta-Analysis Approach

    ERIC Educational Resources Information Center

    Alrasheedi, Muasaad; Capretz, Luiz Fernando

    2015-01-01

    With rapid technological advancements, mobile learning (m-Learning) offers incredible opportunities, especially in the area of higher education. However, while interest in this area has been significant and several pilot studies have been conducted within universities, relatively less is known about how higher educational institutions can make…

  19. Extent of coterminous US rangelands: Quantifying implications of differing agency perspectives

    Treesearch

    Matthew Clark Reeves; John E. Mitchell

    2011-01-01

    Rangeland extent is an important factor for evaluating critical indicators of rangeland sustainability. Rangeland areal extent was determined for the coterminous United States in a geospatial framework by evaluating spatially explicit data from the Landscape Fire and Resource Management Planning Tools (LANDFIRE) project describing historic and current vegetative...

  20. Comparison of measured versus predicted energy requirements in critically ill cancer patients.

    PubMed

    Pirat, Arash; Tucker, Anne M; Taylor, Kim A; Jinnah, Rashida; Finch, Clarence G; Canada, Todd D; Nates, Joseph L

    2009-04-01

    Accurate determination of caloric requirements is essential to avoid feeding-associated complications in critically ill patients. In critically ill cancer patients we compared the measured and estimated resting energy expenditures. All patients admitted to the oncology intensive care unit between March 2004 and July 2005 were considered for inclusion. For those patients enrolled (n = 34) we measured resting energy expenditure via indirect calorimetry, and estimated resting energy expenditure in 2 ways: clinically estimated resting energy expenditure; and the Harris-Benedict basal energy expenditure equation. Clinically estimated resting energy expenditure was associated with underfeeding, appropriate feeding, and overfeeding in approximately 15%, 15%, and 71% of the patients, respectively. The Harris-Benedict basal energy expenditure was associated with underfeeding, appropriate feeding, and overfeeding in approximately 29%, 41%, and 29% of the patients, respectively. The mean measured resting energy expenditure (1,623 +/- 384 kcal/d) was similar to the mean Harris-Benedict basal energy expenditure without the addition of stress or activity factors (1,613 +/- 382 kcal/d, P = .87), and both were significantly lower than the mean clinically estimated resting energy expenditure (1,862 +/- 330 kcal/d, P < or = .003 for both). There was a significant correlation only between mean measured resting energy expenditure and mean Harris-Benedict basal energy expenditure (P < .001), but the correlation coefficient between those values was low (r = 0.587). Underfeeding and overfeeding were common in our critically ill cancer patients when resting energy expenditure was estimated rather than measured. Indirect calorimetry is the method of choice for determining caloric need in critically ill cancer patients, but if indirect calorimetry is not available or feasible, the Harris-Benedict equation without added stress and activity factors is more accurate than the clinically estimated resting energy expenditure.

  1. Haemodialysis, nutritional disorders and hypoglycaemia in critical care.

    PubMed

    Crespo, Jeiel Carlos Lamonica; Gomes, Vanessa Rossato; Barbosa, Ricardo Luís; Padilha, Katia Grillo; Secoli, Silvia Regina

    2017-03-09

    This study aimed to determine hypoglycemia incidence and associated factors in critically ill patients. It looked at a retrospective cohort with 106 critically ill adult patients with 48 hours of glycaemic control and 72 hours of follow up. The dependent variable, hypoglycaemia (≤70 mg/dl), was assessed with respect to independent variables: age, diet, insulin, catecholamines, haemodialysis, nursing workload and the Simplified Acute Physiology Score. Statistical analysis was performed using Student's t-test, Fisher's exact test and logistic regression at 5% significance level. Incidence of hypoglycaemia was 14.2%. Hypoglycaemia was higher in the group of patients on catecholamines (p=0.040), with higher glycaemic variability (p<0.001) and death in the intensive care unit (p=0.008). Risk factors were identified as absence of oral diet (OR 5.11; 95% CI 1.04-25.10) and haemodialysis (OR 4.28; 95% CI 1.16-15.76). Patients on haemodialysis and with no oral diet should have their glycaemic control intensified in order to prevent and/or manage hypoglycaemic episodes.

  2. Constipation in intensive care unit: incidence and risk factors.

    PubMed

    Nassar, Antonio Paulo; da Silva, Fernanda Maria Queiroz; de Cleva, Roberto

    2009-12-01

    Although gastrointestinal motility disorders are common in critically ill patients, constipation and its implications have received very little attention. We aimed to determine the incidence of constipation to find risk factors and its implications in critically ill patients During a 6-month period, we enrolled all patients admitted to an intensive care unit from an universitary hospital who stayed 3 or more days. Patients submitted to bowel surgery were excluded. Constipation occurred in 69.9% of the patients. There was no difference between constipated and not constipated in terms of sex, age, Acute Physiology and Chronic Health Evaluation II, type of admission (surgical, clinical, or trauma), opiate use, antibiotic therapy, and mechanical ventilation. Early (<24 hours) enteral nutrition was associated with less constipation, a finding that persisted at multivariable analysis (P < .01). Constipation was not associated with greater intensive care unit or mortality, length of stay, or days free from mechanical ventilation. Constipation is very common among critically ill patients. Early enteral nutrition is associated with earlier return of bowel function.

  3. Multivariate Approaches for Simultaneous Determination of Avanafil and Dapoxetine by UV Chemometrics and HPLC-QbD in Binary Mixtures and Pharmaceutical Product.

    PubMed

    2016-04-07

    Multivariate UV-spectrophotometric methods and Quality by Design (QbD) HPLC are described for concurrent estimation of avanafil (AV) and dapoxetine (DP) in the binary mixture and in the dosage form. Chemometric methods have been developed, including classical least-squares, principal component regression, partial least-squares, and multiway partial least-squares. Analytical figures of merit, such as sensitivity, selectivity, analytical sensitivity, LOD, and LOQ were determined. QbD consists of three steps, starting with the screening approach to determine the critical process parameter and response variables. This is followed by understanding of factors and levels, and lastly the application of a Box-Behnken design containing four critical factors that affect the method. From an Ishikawa diagram and a risk assessment tool, four main factors were selected for optimization. Design optimization, statistical calculation, and final-condition optimization of all the reactions were Carried out. Twenty-five experiments were done, and a quadratic model was used for all response variables. Desirability plot, surface plot, design space, and three-dimensional plots were calculated. In the optimized condition, HPLC separation was achieved on Phenomenex Gemini C18 column (250 × 4.6 mm, 5 μm) using acetonitrile-buffer (ammonium acetate buffer at pH 3.7 with acetic acid) as a mobile phase at flow rate of 0.7 mL/min. Quantification was done at 239 nm, and temperature was set at 20°C. The developed methods were validated and successfully applied for simultaneous determination of AV and DP in the dosage form.

  4. Aviation accidents and the theory of the situation

    NASA Technical Reports Server (NTRS)

    Bolman, L.

    1980-01-01

    Social-psychological factors effecting the performance of flight crews are examined. In particular, a crew member's perceptual-psychological constructs of the flight situation (theories of the situation) are discussed. The skills and willingness of a flight crew to be alert to possible errors in the theory become critical to their effectiveness and their ability to ensure a safe flight. Several major factors that determine the likelihood that a faulty theory will be detected and revised are identified.

  5. Determinants of HMO success: the case of Complete Health.

    PubMed

    Widra, L S; Fottler, M D

    1992-01-01

    The health maintenance organization (HMO) industry has experienced a variety of difficulties and criticisms in recent years. Various hybrid models have been proposed to alleviate these problems. This article presents an in-depth case study of factors associated with the success of one such hybrid: an individual practice association (IPA)-model HMO affiliated with an academic health center. The major success factors identified include the plan design/structure, the strategic orientation/practices, and the stakeholder management orientation practices.

  6. Critical evaluation of oxygen-uptake assessment in swimming.

    PubMed

    Sousa, Ana; Figueiredo, Pedro; Pendergast, David; Kjendlie, Per-Ludvik; Vilas-Boas, João P; Fernandes, Ricardo J

    2014-03-01

    Swimming has become an important area of sport science research since the 1970s, with the bioenergetic factors assuming a fundamental performance-influencing role. The purpose of this study was to conduct a critical evaluation of the literature concerning oxygen-uptake (VO2) assessment in swimming, by describing the equipment and methods used and emphasizing the recent works conducted in ecological conditions. Particularly in swimming, due to the inherent technical constraints imposed by swimming in a water environment, assessment of VO2max was not accomplished until the 1960s. Later, the development of automated portable measurement devices allowed VO2max to be assessed more easily, even in ecological swimming conditions, but few studies have been conducted in swimming-pool conditions with portable breath-by-breath telemetric systems. An inverse relationship exists between the velocity corresponding to VO2max and the time a swimmer can sustain it at this velocity. The energy cost of swimming varies according to its association with velocity variability. As, in the end, the supply of oxygen (whose limitation may be due to central-O2 delivery and transportation to the working muscles-or peripheral factors-O2 diffusion and utilization in the muscles) is one of the critical factors that determine swimming performance, VO2 kinetics and its maximal values are critical in understanding swimmers' behavior in competition and to develop efficient training programs.

  7. Glutaminemia prognostic significance in critical surgical patients - An analysis of plasma aminogram profile.

    PubMed

    Costa, Beatriz Pinto; Martins, Paulo; Verissimo, Carla; Simões, Marta; Tomé, Marisa; Grazina, Manuela; Pimentel, Jorge; Sousa, Francisco Castro

    2017-07-28

    Glutamine depletion is common in the critically-ill patients. Glutaminemia lower than 420 μmol/l has been considered as an independent predictive factor of mortality, but the indications for exogenous glutamine supplementation remain controversial. This study intends to determine the glutaminemia profile in critical surgical patients and to investigate its correlation with the severity indexes and the prognosis. A prospective study of 28 adult critical surgical patients was performed. Plasma amino acid concentrations were quantified, by ion exchange chromatography, at the moment of admission and at the first and third days, and compared with those of 11 reference healthy individuals. Severity indexes and parameters of prognosis were registered. In critical surgical patients, mean glutaminemia at admission was lower than that of control individuals (385.1 ± 123.1 versus515 ± 57.9 μmol/l, p = 0.002) and decreased until the third day (p = 0.042). Prevalence of severe hypoglutaminemia (< 420 μmol/l) at admission was 64.3%. Baseline glutaminemia correlated with the Simplified Acute Physiology Score II (SAPS II score) (Pearson's correlation coefficient r = -39.4%, p = 0.042), and it was lower in cases of erythrocytes transfusion (339.9 ± 78.8 versus 454.9 ± 148.8 μmol/l, p = 0.013). Glutaminemia at the third day correlated with the duration of invasive ventilation support (r = -65%, p = 0 .012) and ICU stay (r = -66.5%, p = 0.009). Glutaminemia below 320 μmol/l, observed in 25% of the patients, was associated with higher in-hospital mortality (42.9 versus19%, statistically not significant [n.s.]) and lower actuarial survival (212.1 ± 77.9 versus 262.3 ± 32.4 days, n.s.). Those results underscore the relevance of hypoglutaminemia as an adverse predictive factor in the critical surgical patients. Determination of glutaminemia may contribute to a better definition of the indications for glutamine supplementation.

  8. Determinants of burnout in acute and critical care military nursing personnel: a cross-sectional study from Peru.

    PubMed

    Ayala, Elizabeth; Carnero, Andrés M

    2013-01-01

    Evidence on the prevalence and determinants of burnout among military acute and critical care nursing personnel from developing countries is minimal, precluding the development of effective preventive measures for this high-risk occupational group. In this context, we aimed to examine the association between the dimensions of burnout and selected socio-demographic and occupational factors in military acute/critical care nursing personnel from Lima, Peru. We conducted a cross-sectional study in 93 nurses/nurse assistants from the acute and critical care departments of a large, national reference, military hospital in Lima, Peru, using a socio-demographic/occupational questionnaire and a validated Spanish translation of the Maslach Burnout Inventory. Total scores for each of the burnout dimensions were calculated for each participant. Higher emotional exhaustion and depersonalisation scores, and lower personal achievement scores, implied a higher degree of burnout. We used linear regression to evaluate the association between each of the burnout dimensions and selected socio-demographic and occupational characteristics, after adjusting for potential confounders. The associations of the burnout dimensions were heterogeneous for the different socio-demographic and occupational factors. Higher emotional exhaustion scores were independently associated with having children (p<0.05) and inversely associated with the time working in the current department (p<0.05). Higher depersonalization scores were independently associated with being single compared with being divorced, separated or widowed (p<0.01), working in the emergency room/intensive care unit compared with the recovery room (p<0.01), and inversely associated with age (p<0.05). Finally, higher personal achievement scores were independently associated with having children (p<0.05). Among Peruvian military acute and critical care nursing personnel, potential screening and preventive interventions should focus on younger/less experienced nurses/nurse assistants, who are single, have children, or work in the most acute critical care areas (e.g. the emergency room/intensive care unit).

  9. Evaluation of factors affecting the edge formability of two hot rolled multiphase steels

    NASA Astrophysics Data System (ADS)

    Mukherjee, Monideepa; Tiwari, Sumit; Bhattacharya, Basudev

    2018-02-01

    In this study, the effect of various factors on the hole expansion ratio and hence on the edge formability of two hot rolled multiphase steels, one with a ferrite-martensite microstructure and the other with a ferrite-bainite microstructure, was investigated through systematic microstructural and mechanical characterization. The study revealed that the microstructure of the steels, which determines their strain hardening capacity and fracture resistance, is the principal factor controlling edge formability. The influence of other factors such as tensile strength, ductility, anisotropy, and thickness, though present, are secondary. A critical evaluation of the available empirical models for hole expansion ratio prediction is also presented.

  10. College Students Coping with Interpersonal Stress: Examining a Control-Based Model of Coping

    ERIC Educational Resources Information Center

    Coiro, Mary Jo; Bettis, Alexandra H.; Compas, Bruce E.

    2017-01-01

    Objective: The ways that college students cope with stress, particularly interpersonal stress, may be a critical factor in determining which students are at risk for impairing mental health disorders. Using a control-based model of coping, the present study examined associations between interpersonal stress, coping strategies, and symptoms.…

  11. Action Alters Object Identification: Wielding a Gun Increases the Bias to See Guns

    ERIC Educational Resources Information Center

    Witt, Jessica K.; Brockmole, James R.

    2012-01-01

    Stereotypes, expectations, and emotions influence an observer's ability to detect and categorize objects as guns. In light of recent work in action-perception interactions, however, there is another unexplored factor that may be critical: The action choices available to the perceiver. In five experiments, participants determined whether another…

  12. Significant Life Experiences on the Formation of Environmental Action among Chinese College Students

    ERIC Educational Resources Information Center

    Li, Danqing; Chen, Jin

    2015-01-01

    Determining the factors that influence young adults' engagement in environmental action is critical to further developing their active and important participation in environmental issues. In this paper, we designed two studies to identify life experiences of Chinese college students that foster environmental action. In Study 1, we used an…

  13. Do the Critical Success Factors from Learning Analytics Predict Student Outcomes?

    ERIC Educational Resources Information Center

    Strang, Kenneth David

    2016-01-01

    This article starts with a detailed literature review of recent studies that focused on using learning analytics software or learning management system data to determine the nature of any relationships between online student activity and their academic outcomes within university-level business courses. The article then describes how data was…

  14. Negligent Liability and the Foreseeability Factor: A Critical Issue for School Counselors.

    ERIC Educational Resources Information Center

    Henderson, Donald H.

    1987-01-01

    Notes that negligent liability suits involving school counselors seem to be increasing. Cites cases, most of which involved defendant's alleged negligence emanating from failure to provide reasonable care to individuals who were later injured or killed. Emphasizes role of foreseeability in determining outcome of negligence cases. Indicates areas…

  15. A Brief Review of Effective Teaching Practices That Maximize Student Engagement

    ERIC Educational Resources Information Center

    Harbour, Kristin E.; Evanovich, Lauren L.; Sweigart, Chris A.; Hughes, Lindsay E.

    2015-01-01

    What teachers do and how students perform intersect, making teachers a critical factor for determining student success. When teachers use effective practices, they maximize the probability that students will be actively engaged in instruction. Student engagement is one of the most well-established predictors of achievement; when students are more…

  16. Improving fungal disease forecasts in winter wheat: a critical role of intra-day variations of meteorological conditions

    USDA-ARS?s Scientific Manuscript database

    Meteorological conditions are important factors in the development of fungal diseases in winter wheat and are the main inputs of the decision support systems used to forecast disease and thus determine timing for efficacious fungicide application. This study uses the Fourier transform method (FTM) t...

  17. A Framework for Developing Self-Directed Technology Use for Language Learning

    ERIC Educational Resources Information Center

    Lai, Chun

    2013-01-01

    Critical to maximizing the potential of technology for learning is enhancing language learners' self-directed use of technology for learning purposes. This study aimed to enhance our understanding of the determinants of self-directed technology use through the construction of a structural equation modelling (SEM) framework of factors and…

  18. Antiluteolytic strategies to improve fertility in cattle.

    PubMed

    Binelli, M; Thatcher, W W; Mattos, R; Baruselli, P S

    2001-12-01

    During early pregnancy, a "critical period" may be defined between Days 15 and 17. Embryonic mortality associated with this period causes significant economic losses to the cattle industry. During this period, the endometrium will follow a default program to release luteolytic pulses of PGF2alpha, unless the conceptus sends appropriate antiluteolytic signals to block PGF2alpha, production. Maintenance of pregnancy is dependent on a successful blockage of endometrial PGF2alpha production. Biology of the critical period is complex and multifactorial. Endocrine, cellular and molecular factors, both from maternal and conceptus origins act in concert to determine whether luteolysis or maintenance of pregnancy will prevail. Understanding the influences of such factors in the biology of the critical period allowed researchers to produce a series of strategies aiming to favor maintenance of pregnancy in lieu of luteolysis. Strategies include hormonal and nutritional manipulations to decrease plasma concentrations of estradiol 17beta (E2) while increasing those of progesterone (P4), and inhibiting the PGF2alpha-synthesizing enzymatic machinery in the endometrium during the critical period. Experimental results indicate that use of such strategies has improved pregnancy rates following artificial insemination and embryo transfer programs.

  19. The determinants of alternative RNA splicing in human cells.

    PubMed

    Ramanouskaya, Tatsiana V; Grinev, Vasily V

    2017-12-01

    Alternative splicing represents an important level of the regulation of gene function in eukaryotic organisms. It plays a critical role in virtually every biological process within an organism, including regulation of cell division and cell death, differentiation of tissues in the embryo and the adult organism, as well as in cellular response to diverse environmental factors. In turn, studies of the last decade have shown that alternative splicing itself is controlled by different mechanisms. Unfortunately, there is no clear understanding of how these diverse mechanisms, or determinants, regulate and constrain the set of alternative RNA species produced from any particular gene in every cell of the human body. Here, we provide a consolidated overview of alternative splicing determinants including RNA-protein interactions, epigenetic regulation via chromatin remodeling, coupling of transcription-to-alternative splicing, effect of secondary structures in pre-RNA, and function of the RNA quality control systems. We also extensively and critically discuss some mechanistic insights on coordinated inclusion/exclusion of exons during the formation of mature RNA molecules. We conclude that the final structure of RNA is pre-determined by a complex interplay between cis- and trans-acting factors. Altogether, currently available empirical data significantly expand our understanding of the functioning of the alternative splicing machinery of cells in normal and pathological conditions. On the other hand, there are still many blind spots that require further deep investigations.

  20. Critical loads of nitrogen deposition and critical levels of atmospheric ammonia for semi-natural Mediterranean evergreen woodlands

    NASA Astrophysics Data System (ADS)

    Pinho, P.; Theobald, M. R.; Dias, T.; Tang, Y. S.; Cruz, C.; Martins-Loução, M. A.; Máguas, C.; Sutton, M.; Branquinho, C.

    2012-03-01

    Nitrogen (N) has emerged in recent years as a key factor associated with global changes, with impacts on biodiversity, ecosystems functioning and human health. In order to ameliorate the effects of excessive N, safety thresholds such as critical loads (deposition fluxes) and levels (concentrations) can be established. Few studies have assessed these thresholds for semi-natural Mediterranean ecosystems. Our objective was therefore to determine the critical loads of N deposition and long-term critical levels of atmospheric ammonia for semi-natural Mediterranean evergreen woodlands. We have considered changes in epiphytic lichen communities, one of the most sensitive comunity indicators of excessive N in the atmosphere. Based on a classification of lichen species according to their tolerance to N we grouped species into response functional groups, which we used as a tool to determine the critical loads and levels. This was done for a Mediterranean climate in evergreen cork-oak woodlands, based on the relation between lichen functional diversity and modelled N deposition for critical loads and measured annual atmospheric ammonia concentrations for critical levels, evaluated downwind from a reduced N source (a cattle barn). Modelling the highly significant relationship between lichen functional groups and annual atmospheric ammonia concentration showed the critical level to be below 1.9 μg m-3, in agreement with recent studies for other ecosystems. Modelling the highly significant relationship between lichen functional groups and N deposition showed that the critical load was lower than 26 kg (N) ha-1 yr-1, which is within the upper range established for other semi-natural ecosystems. Taking into account the high sensitivity of lichen communities to excessive N, these values should aid development of policies to protect Mediterranean woodlands from the initial effects of excessive N.

  1. Obesity, Oxidative Stress, Adipose Tissue Dysfunction, and the Associated Health Risks: Causes and Therapeutic Strategies.

    PubMed

    Manna, Prasenjit; Jain, Sushil K

    2015-12-01

    Obesity is gaining acceptance as a serious primary health burden that impairs the quality of life because of its associated complications, including diabetes, cardiovascular diseases, cancer, asthma, sleep disorders, hepatic dysfunction, renal dysfunction, and infertility. It is a complex metabolic disorder with a multifactorial origin. Growing evidence suggests that oxidative stress plays a role as the critical factor linking obesity with its associated complications. Obesity per se can induce systemic oxidative stress through various biochemical mechanisms, such as superoxide generation from NADPH oxidases, oxidative phosphorylation, glyceraldehyde auto-oxidation, protein kinase C activation, and polyol and hexosamine pathways. Other factors that also contribute to oxidative stress in obesity include hyperleptinemia, low antioxidant defense, chronic inflammation, and postprandial reactive oxygen species generation. In addition, recent studies suggest that adipose tissue plays a critical role in regulating the pathophysiological mechanisms of obesity and its related co-morbidities. To establish an adequate platform for the prevention of obesity and its associated health risks, understanding the factors that contribute to the cause of obesity is necessary. The most current list of obesity determinants includes genetic factors, dietary intake, physical activity, environmental and socioeconomic factors, eating disorders, and societal influences. On the basis of the currently identified predominant determinants of obesity, a broad range of strategies have been recommended to reduce the prevalence of obesity, such as regular physical activity, ad libitum food intake limiting to certain micronutrients, increased dietary intake of fruits and vegetables, and meal replacements. This review aims to highlight recent findings regarding the role of oxidative stress in the pathogenesis of obesity and its associated risk factors, the role of dysfunctional adipose tissue in development of these risk factors, and potential strategies to regulate body weight loss/gain for better health benefits.

  2. Obesity, Oxidative Stress, Adipose Tissue Dysfunction, and the Associated Health Risks: Causes and Therapeutic Strategies

    PubMed Central

    Manna, Prasenjit

    2015-01-01

    Abstract Obesity is gaining acceptance as a serious primary health burden that impairs the quality of life because of its associated complications, including diabetes, cardiovascular diseases, cancer, asthma, sleep disorders, hepatic dysfunction, renal dysfunction, and infertility. It is a complex metabolic disorder with a multifactorial origin. Growing evidence suggests that oxidative stress plays a role as the critical factor linking obesity with its associated complications. Obesity per se can induce systemic oxidative stress through various biochemical mechanisms, such as superoxide generation from NADPH oxidases, oxidative phosphorylation, glyceraldehyde auto-oxidation, protein kinase C activation, and polyol and hexosamine pathways. Other factors that also contribute to oxidative stress in obesity include hyperleptinemia, low antioxidant defense, chronic inflammation, and postprandial reactive oxygen species generation. In addition, recent studies suggest that adipose tissue plays a critical role in regulating the pathophysiological mechanisms of obesity and its related co-morbidities. To establish an adequate platform for the prevention of obesity and its associated health risks, understanding the factors that contribute to the cause of obesity is necessary. The most current list of obesity determinants includes genetic factors, dietary intake, physical activity, environmental and socioeconomic factors, eating disorders, and societal influences. On the basis of the currently identified predominant determinants of obesity, a broad range of strategies have been recommended to reduce the prevalence of obesity, such as regular physical activity, ad libitum food intake limiting to certain micronutrients, increased dietary intake of fruits and vegetables, and meal replacements. This review aims to highlight recent findings regarding the role of oxidative stress in the pathogenesis of obesity and its associated risk factors, the role of dysfunctional adipose tissue in development of these risk factors, and potential strategies to regulate body weight loss/gain for better health benefits. PMID:26569333

  3. Antagonism between the transcription factors NANOG and OTX2 specifies rostral or caudal cell fate during neural patterning transition.

    PubMed

    Su, Zhenghui; Zhang, Yanqi; Liao, Baojian; Zhong, Xiaofen; Chen, Xin; Wang, Haitao; Guo, Yiping; Shan, Yongli; Wang, Lihui; Pan, Guangjin

    2018-03-23

    During neurogenesis, neural patterning is a critical step during which neural progenitor cells differentiate into neurons with distinct functions. However, the molecular determinants that regulate neural patterning remain poorly understood. Here we optimized the "dual SMAD inhibition" method to specifically promote differentiation of human pluripotent stem cells (hPSCs) into forebrain and hindbrain neural progenitor cells along the rostral-caudal axis. We report that neural patterning determination occurs at the very early stage in this differentiation. Undifferentiated hPSCs expressed basal levels of the transcription factor orthodenticle homeobox 2 (OTX2) that dominantly drove hPSCs into the "default" rostral fate at the beginning of differentiation. Inhibition of glycogen synthase kinase 3β (GSK3β) through CHIR99021 application sustained transient expression of the transcription factor NANOG at early differentiation stages through Wnt signaling. Wnt signaling and NANOG antagonized OTX2 and, in the later stages of differentiation, switched the default rostral cell fate to the caudal one. Our findings have uncovered a mutual antagonism between NANOG and OTX2 underlying cell fate decisions during neural patterning, critical for the regulation of early neural development in humans. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Factors affecting consent in pediatric critical care research.

    PubMed

    Menon, Kusum; Ward, Roxanne E; Gaboury, Isabelle; Thomas, Margot; Joffe, Ari; Burns, Karen; Cook, Deborah

    2012-01-01

    Consent for research is a difficult and unpredictable process in pediatric critical care populations. The objectives of this study were to describe consent rates in pediatric critical care research and their association with patient, legal guardian, consent process, and study design-related factors. A prospective, cohort study was conducted from 2009 to 2010 in six tertiary care pediatric intensive care units (PICU) in Canada with legal guardians of patients who were approached for consent for any ongoing PICU research study. Data were recorded on details of the consent process for all consent encounters. We recorded 271 consent encounters. The overall consent rate was 80.1% (217/271). We observed higher consent rates when the research assistant was introduced by a member of the clinical team prior to approaching the family (89.7 vs. 77.7%; P = 0.04). Legal guardians of cardiac surgery patients were less likely to provide consent than those of all other patients (75.3 vs. 86.0%; P = 0.03). There was no difference in consent rates between therapeutic (117/145, 80.7%) versus non-therapeutic studies (100/126, 79.4%; P = 0.88). This study provides future researchers with consent data for determination of recruitment rates, sample sizes, budget estimations, and study timelines. Future pediatric critical care studies should consider incorporating the lower consent rates in cardiac surgery patients and routine introduction of the research assistant to the family by a member of the patient's care team into their study designs. The potential influence of parental factors on consent rates in pediatric critical care studies requires further research.

  5. Role of brain-derived neurotrophic factor in the excitatory-inhibitory imbalance during the critical period of postnatal respiratory development in the rat.

    PubMed

    Gao, Xiu-Ping; Zhang, Hanmeng; Wong-Riley, Margaret

    2015-11-01

    The critical period of respiratory development in rats is a narrow window toward the end of the second postnatal week (P12-13), when abrupt neurochemical, electrophysiological, and ventilatory changes occur, when inhibition dominates over excitation, and when the animals' response to hypoxia is the weakest. The goal of this study was to further test our hypothesis that a major mechanism underlying the synaptic imbalance during the critical period is a reduced expression of brain-derived neurotrophic factor (BDNF) and its TrkB receptors. Our aims were to determine (1) that the inhibitory dominance observed in hypoglossal motoneurons during the critical period was also demonstrable in a key respiratory chemosensor, NTSVL; (2) if in vivo application of a TrkB agonist, 7,8-DHF, would prevent, but a TrkB antagonist, ANA-12, would accentuate the synaptic imbalance; and (3) if hypoxia would also heighten the imbalance. Our results indicate that (1) the synaptic imbalance was evident in the NTSVL during the critical period; (2) intraperitoneal injections of 7,8-DHF prevented the synaptic imbalance during the critical period, whereas ANA-12 in vivo accentuated such an imbalance; and (3) acute hypoxia induced the weakest response in both the amplitude and frequency of sEPSCs during the critical period, but it increased the frequency of sIPSCs during the critical period. Thus, our findings are consistent with and strengthen our hypothesis that BDNF and TrkB play a significant role in inducing a synaptic imbalance during the critical period of respiratory development in the rat. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  6. A knowledge-based taxonomy of critical factors for adopting electronic health record systems by physicians: a systematic literature review

    PubMed Central

    2010-01-01

    Background The health care sector is an area of social and economic interest in several countries; therefore, there have been lots of efforts in the use of electronic health records. Nevertheless, there is evidence suggesting that these systems have not been adopted as it was expected, and although there are some proposals to support their adoption, the proposed support is not by means of information and communication technology which can provide automatic tools of support. The aim of this study is to identify the critical adoption factors for electronic health records by physicians and to use them as a guide to support their adoption process automatically. Methods This paper presents, based on the PRISMA statement, a systematic literature review in electronic databases with adoption studies of electronic health records published in English. Software applications that manage and process the data in the electronic health record have been considered, i.e.: computerized physician prescription, electronic medical records, and electronic capture of clinical data. Our review was conducted with the purpose of obtaining a taxonomy of the physicians main barriers for adopting electronic health records, that can be addressed by means of information and communication technology; in particular with the information technology roles of the knowledge management processes. Which take us to the question that we want to address in this work: "What are the critical adoption factors of electronic health records that can be supported by information and communication technology?". Reports from eight databases covering electronic health records adoption studies in the medical domain, in particular those focused on physicians, were analyzed. Results The review identifies two main issues: 1) a knowledge-based classification of critical factors for adopting electronic health records by physicians; and 2) the definition of a base for the design of a conceptual framework for supporting the design of knowledge-based systems, to assist the adoption process of electronic health records in an automatic fashion. From our review, six critical adoption factors have been identified: user attitude towards information systems, workflow impact, interoperability, technical support, communication among users, and expert support. The main limitation of the taxonomy is the different impact of the adoption factors of electronic health records reported by some studies depending on the type of practice, setting, or attention level; however, these features are a determinant aspect with regard to the adoption rate for the latter rather than the presence of a specific critical adoption factor. Conclusions The critical adoption factors established here provide a sound theoretical basis for research to understand, support, and facilitate the adoption of electronic health records to physicians in benefit of patients. PMID:20950458

  7. Matrix Remodeling in Pulmonary Fibrosis and Emphysema

    PubMed Central

    O’Reilly, Philip; Antony, Veena B.; Gaggar, Amit

    2016-01-01

    Pulmonary fibrosis and emphysema are chronic lung diseases characterized by a progressive decline in lung function, resulting in significant morbidity and mortality. A hallmark of these diseases is recurrent or persistent alveolar epithelial injury, typically caused by common environmental exposures such as cigarette smoke. We propose that critical determinants of the outcome of the injury-repair processes that result in fibrosis versus emphysema are mesenchymal cell fate and associated extracellular matrix dynamics. In this review, we explore the concept that regulation of mesenchymal cells under the influence of soluble factors, in particular transforming growth factor-β1, and the extracellular matrix determine the divergent tissue remodeling responses seen in pulmonary fibrosis and emphysema. PMID:26741177

  8. Underwater topography determines critical breeding habitat for humpback whales near Osa Peninsula, Costa Rica: implications for marine protected areas.

    PubMed

    Oviedo, L; Solís, M

    2008-06-01

    Migrating humpback whales from northern and southern feeding grounds come to the tropical waters near Osa Peninsula, Pacific of Costa Rica, to reproduce and raise their calves. Planning effective marine protected areas that encompass humpback critical habitats require data about which oceanographic features influence distribution during the breeding period. This study examines the relationship between water depth and ocean floor slope with humpback whale distribution, based on sightings during two breeding seasons (2005 and 2006). Data are from the Southern and Northern subpopulations in the Eastern Tropical Pacific (ETP). Analysis followed the basic principles of the Ecological Niche Factors Analysis (ENFA), where indices of Marginality and Tolerance provide insights on the restrictiveness of habitat use. At a fine scale, physical factors such as water depth and slope define the critical breeding and nursing habitat for M. novaeangliae. Divergence in the subsamples means of depths and slope distribution, with the global mean of the study area in both eco-geographical variables, determine habitat requirements restricted by topographic features such as depths (< 100 m) and slope (< 10%), and locate the key breeding and nursing habitat of the species within the continental shelf domains. Proposed Marine Protected Areas (MPA's) network plans should consider connectivity of Cafio Island-Drake Bay and the extension of Corcovado National Park maritime borders.

  9. Internal and external environmental factors affecting the performance of hospital-based home nursing care.

    PubMed

    Noh, J-W; Kwon, Y-D; Yoon, S-J; Hwang, J-I

    2011-06-01

    Numerous studies on HNC services have been carried out by signifying their needs, efficiency and effectiveness. However, no study has ever been performed to determine the critical factors associated with HNC's positive results despite the deluge of positive studies on the service. This study included all of the 89 training hospitals that were practising HNC service in Korea as of November 2006. The input factors affecting the performance were classified as either internal or external environmental factors. This analysis was conducted to understand the impact that the corresponding factors had on performance. Data were analysed by using multiple linear regressions. The internal and external environment variables affected the performance of HNC based on univariate analysis. The meaningful variables were internal environmental factors. Specifically, managerial resource (the number of operating beds and the outpatient/inpatient ratio) were meaningful when the multiple linear regression analysis was performed. Indeed, the importance of organizational culture (the passion of HNC nurses) was significant. This study, considering the limited market size of Korea, illustrates that the critical factor for the development of hospital-led HNC lies with internal environmental factors rather than external ones. Among the internal environmental factors, the hospitals' managerial resource-related factors (specifically, the passion of nurses) were the most important contributing element. © 2011 The Authors. International Nursing Review © 2011 International Council of Nurses.

  10. Molecular dynamics simulation on the elastoplastic properties of copper nanowire under torsion

    NASA Astrophysics Data System (ADS)

    Yang, Yong; Li, Ying; Yang, Zailin; Zhang, Guowei; Wang, Xizhi; Liu, Jin

    2018-02-01

    Influences of different factors on the torsion properties of single crystal copper nanowire are studied by molecular dynamics method. The length, torsional rate, and temperature of the nanowire are discussed at the elastic-plastic critical point. According to the average potential energy curve and shear stress curve, the elastic-plastic critical angle is determined. Also, the dislocation at elastoplastic critical points is analyzed. The simulation results show that the single crystal copper nanowire can be strengthened by lengthening the model, decreasing the torsional rate, and lowering the temperature. Moreover, atoms move violently and dislocation is more likely to occur with a higher temperature. This work mainly describes the mechanical behavior of the model under different states.

  11. Psychometric properties of the Persian version of the Intensive and Critical Care Nursing Competence Scale version-1 (ICCN-CS-1)

    PubMed Central

    Shouryabi, Ali Asghar; Ghahrisarabi, Alireza; Anboohi, Sima Zohari; Nasiri, Malihe; Rassouli, Maryam

    2017-01-01

    Background Nursing competence is highly related to patient outcomes and patient safety issues, especially in intensive care units. Competence assessment tools are needed specifically for intensive care nursing. Objective This study was performed to determine psychometric properties of the Intensive and Critical Care Nursing Competence Scale version-1 between Iranian Nurses. Methods The present study was a methodological research in which 289 nurses of Intensive Care Units from nine hospitals in Shahid Beheshti University of Medical Sciences in Tehran were selected between 2015 and 2016. The original version of the scale was translated into Persian and back-translated into English, and the comments of the developer were applied. The validity of the scale was the determined quality (content validity and face validity) and quantity (confirmatory factor analysis). Reliability of the scale was reported by Cronbach’s alpha coefficient and Intra class Correlation Coefficient. SPSS-PC (v.21) and LISREL (v.8.5) were used to analyze the data. Results The intensive and critical care nursing competence scale version-1 is a self-assessment test that consists of 144 items and four domains which are the knowledge base, the skill base, the attitudes and values base and the experience base, which are divided into clinical competence and professional competence. Content and face validity was confirmed by 10 experts and 10 practitioner nurses in the intensive care units. In confirmatory factor analysis, all fitness indexes, except goodness of fit index (0.64), confirmed the four-factor structure of the ICCN-CS-1. The results of the factor analysis, load factor between 0.304 and 0.727 items was estimated; only 4 items out of 144 items, that were loaded were less than 0.3 due to high Cronbach’s alpha coefficient (0.984–0.986), all items were preserved, no item was removed and 4 subscales of the original scale were confirmed. Conclusion The results of this study indicated that the Persian version of “The Intensive and Critical Care Nursing Competence Scale version-1” is a valid and reliable scale for the assessment of competency among Iranian nurses, and it can be used as a reliable scale in nursing management, education and research. PMID:29403620

  12. Risk factors for hospital-associated venous thromboembolism in critically ill children following cardiothoracic surgery or therapeutic cardiac catheterisation.

    PubMed

    Atchison, Christie M; Amankwah, Ernest; Wilhelm, Jean; Arlikar, Shilpa; Branchford, Brian R; Stock, Arabela; Streiff, Michael; Takemoto, Clifford; Ayala, Irmel; Everett, Allen; Stapleton, Gary; Jacobs, Marshall L; Jacobs, Jeffrey P; Goldenberg, Neil A

    2018-02-01

    Paediatric hospital-associated venous thromboembolism is a leading quality and safety concern at children's hospitals. The aim of this study was to determine risk factors for hospital-associated venous thromboembolism in critically ill children following cardiothoracic surgery or therapeutic cardiac catheterisation. We conducted a retrospective, case-control study of children admitted to the cardiovascular intensive care unit at Johns Hopkins All Children's Hospital (St. Petersburg, Florida, United States of America) from 2006 to 2013. Hospital-associated venous thromboembolism cases were identified based on ICD-9 discharge codes and validated using radiological record review. We randomly selected two contemporaneous cardiovascular intensive care unit controls without hospital-associated venous thromboembolism for each hospital-associated venous thromboembolism case, and limited the study population to patients who had undergone cardiothoracic surgery or therapeutic cardiac catheterisation. Odds ratios and 95% confidence intervals for associations between putative risk factors and hospital-associated venous thromboembolism were determined using univariate and multivariate logistic regression. Among 2718 admissions to the cardiovascular intensive care unit during the study period, 65 met the criteria for hospital-associated venous thromboembolism (occurrence rate, 2%). Restriction to cases and controls having undergone the procedures of interest yielded a final study population of 57 hospital-associated venous thromboembolism cases and 76 controls. In a multiple logistic regression model, major infection (odds ratio=5.77, 95% confidence interval=1.06-31.4), age ⩽1 year (odds ratio=6.75, 95% confidence interval=1.13-160), and central venous catheterisation (odds ratio=7.36, 95% confidence interval=1.13-47.8) were found to be statistically significant independent risk factors for hospital-associated venous thromboembolism in these children. Patients with all three factors had a markedly increased post-test probability of having hospital-associated venous thromboembolism. Major infection, infancy, and central venous catheterisation are independent risk factors for hospital-associated venous thromboembolism in critically ill children following cardiothoracic surgery or cardiac catheter-based intervention, which, in combination, define a high-risk group for hospital-associated venous thromboembolism.

  13. Environmental economics of lignin derived transport fuels.

    PubMed

    Obydenkova, Svetlana V; Kouris, Panos D; Hensen, Emiel J M; Heeres, Hero J; Boot, Michael D

    2017-11-01

    This paper explores the environmental and economic aspects of fast pyrolytic conversion of lignin, obtained from 2G ethanol plants, to transport fuels for both the marine and automotive markets. Various scenarios are explored, pertaining to aggregation of lignin from several sites, alternative energy carries to replace lignin, transport modalities, and allocation methodology. The results highlight two critical factors that ultimately determine the economic and/or environmental fuel viability. The first factor, the logistics scheme, exhibited the disadvantage of the centralized approach, owing to prohibitively expensive transportation costs of the low energy-dense lignin. Life cycle analysis (LCA) displayed the second critical factor related to alternative energy carrier selection. Natural gas (NG) chosen over additional biomass boosts well-to-wheel greenhouse gas emissions (WTW GHG) to a level incompatible with the reduction targets set by the U.S. renewable fuel standard (RFS). Adversely, the process' economics revealed higher profits vs. fossil energy carrier. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  14. A critical analysis of one standard and five methods to monitor surface wetness and time-of-wetness

    NASA Astrophysics Data System (ADS)

    Camuffo, Dario; della Valle, Antonio; Becherini, Francesca

    2018-05-01

    Surface wetness is a synergistic factor to determine atmospheric corrosion, monument weathering, mould growth, sick buildings, etc. However, its detection and monitoring are neither easy nor homogeneous, for a number of factors that may affect readings. Various types of methods and sensors, either commercial or prototypes built in the lab, have been investigated and compared, i.e. the international standard ISO 9223 to evaluate corrosivity after wetness and time-of-wetness; indirect evaluation of wetness, based on the dew point calculated after the output of temperature and relative humidity sensors and direct measurements by means of capacitive wetness sensors, safety sensors, rain sensors (also known as leaf wetness sensors), infrared reflection sensors and fibre optic sensors. A comparison between the different methods is presented, specifying physical principles, forms of wetting to which they are respondent (i.e. condensation, ice melting, splashing drops, percolation and capillary rise), critical factors, use and cost.

  15. Shaping vulnerability to addiction - the contribution of behavior, neural circuits and molecular mechanisms.

    PubMed

    Egervari, Gabor; Ciccocioppo, Roberto; Jentsch, J David; Hurd, Yasmin L

    2018-02-01

    Substance use disorders continue to impose increasing medical, financial and emotional burdens on society in the form of morbidity and overdose, family disintegration, loss of employment and crime, while advances in prevention and treatment options remain limited. Importantly, not all individuals exposed to abused substances effectively develop the disease. Genetic factors play a significant role in determining addiction vulnerability and interactions between innate predisposition, environmental factors and personal experiences are also critical. Thus, understanding individual differences that contribute to the initiation of substance use as well as on long-term maladaptations driving compulsive drug use and relapse propensity is of critical importance to reduce this devastating disorder. In this paper, we discuss current topics in the field of addiction regarding individual vulnerability related to behavioral endophenotypes, neural circuits, as well as genetics and epigenetic mechanisms. Expanded knowledge of these factors is of importance to improve and personalize prevention and treatment interventions in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. A review and prospects for Nb3Sn superconductor development

    NASA Astrophysics Data System (ADS)

    Xu, Xingchen

    2017-09-01

    Nb3Sn superconductors have significant applications in constructing high-field (>10 T) magnets. This article briefly reviews development of Nb3Sn superconductor and proposes prospects for further improvement. It is shown that significant improvement of critical current density (J c) is needed for future accelerator magnets. After a brief review of the development of Nb3Sn superconductors, the factors controlling J c are summarized and correlated with their microstructure and chemistry. The non-matrix J c of Nb3Sn conductors is mainly determined by three factors: the fraction of current-carrying Nb3Sn phase in the non-matrix area, the upper critical field B c2, and the flux line pinning capacity. Then prospects to improve the three factors are discussed respectively. An analytic model was developed to show how the ratios of precursors determine the phase fractions after heat treatment, based on which it is predicted that the limit of current-carrying Nb3Sn fraction in subelements is ∼65%. Then, since B c2 is largely determined by the Nb3Sn stoichiometry, a thermodynamic/kinetic theory is presented to show what essentially determines the Sn content of Nb3Sn conductors. This theory explains the influences of Sn sources and Ti addition on stoichiometry and growth rate of Nb3Sn layers. Next, to improve flux pinning, previous efforts in this community to introduce additional pinning centers to Nb3Sn wires are reviewed, and an internal oxidation technique is described. Finally, prospects for further improvement of non-matrix J c of Nb3Sn conductors are discussed, and it is seen that the only opportunity for further significantly improving J c lies in improving flux pinning.

  17. A review and prospects for Nb 3Sn superconductor development

    DOE PAGES

    Xu, Xingchen

    2017-08-03

    Nb 3Sn superconductors have significant applications in constructing high-field (> 10 T) magnets. This article briefly reviews development of Nb 3Sn superconductor and proposes prospects for further improvement. It is shown that significant improvement of critical current density (J c) is needed for future accelerator magnets. After a brief review of the development of Nb 3Sn superconductors, the factors controlling J c are summarized and correlated with their microstructure and chemistry. The non-matrix J c of Nb 3Sn conductors is mainly determined by three factors: the fraction of current-carrying Nb 3Sn phase in the non-matrix area, the upper critical fieldmore » B c2, and the flux-line pinning capacity. Then prospects to improve the three factors are discussed respectively. An analytic model was developed to show how the ratios of precursors determine the phase fractions after heat treatment, based on which it is predicted that the limit of current-carrying Nb 3Sn fraction in subelements is ~65%. Then, since B c2 is largely determined by the Nb 3Sn stoichiometry, a thermodynamic/kinetic theory was presented to show what essentially determines the Sn content of Nb 3Sn conductors. This theory explains the influences of Sn sources and Ti addition on stoichiometry and growth rate of Nb 3Sn layers. Next, to improve flux pinning, previous efforts in this community to introduce additional pinning centers (APC) to Nb 3Sn wires are reviewed, and an internal oxidation technique is described. Lastly, prospects for further improvement of non-matrix J c of Nb 3Sn conductors are discussed, and it is seen that the only opportunity for further significantly improving J c lies in improving the flux pinning.« less

  18. Intracellular Drug Concentrations and Transporters: Measurement, Modeling, and Implications for the Liver

    PubMed Central

    Chu, X; Korzekwa, K; Elsby, R; Fenner, K; Galetin, A; Lai, Y; Matsson, P; Moss, A; Nagar, S; Rosania, GR; Bai, JPF; Polli, JW; Sugiyama, Y; Brouwer, KLR

    2013-01-01

    Intracellular concentrations of drugs and metabolites are often important determinants of efficacy, toxicity, and drug interactions. Hepatic drug distribution can be affected by many factors, including physicochemical properties, uptake/efflux transporters, protein binding, organelle sequestration, and metabolism. This white paper highlights determinants of hepatocyte drug/metabolite concentrations and provides an update on model systems, methods, and modeling/simulation approaches used to quantitatively assess hepatocellular concentrations of molecules. The critical scientific gaps and future research directions in this field are discussed. PMID:23588320

  19. The bias of experimental design, including strain background, in the determination of critical Streptococcus suis serotype 2 virulence factors

    PubMed Central

    Auger, Jean-Philippe; Chuzeville, Sarah; Roy, David; Mathieu-Denoncourt, Annabelle; Xu, Jianguo; Grenier, Daniel

    2017-01-01

    Streptococcus suis serotype 2 is an important porcine bacterial pathogen and emerging zoonotic agent mainly responsible for sudden death, septic shock, and meningitis. However, serotype 2 strains are genotypically and phenotypically heterogeneous. Though a multitude of virulence factors have been described for S. suis serotype 2, the lack of a clear definition regarding which ones are truly “critical” has created inconsistencies that have only recently been highlighted. Herein, the involvement of two factors previously described as being critical for S. suis serotype 2 virulence, whether the dipeptidyl peptidase IV and autolysin, were evaluated with regards to different ascribed functions using prototype strains belonging to important sequence types. Results demonstrate a lack of reproducibility with previously published data. In fact, the role of the dipeptidyl peptidase IV and autolysin as critical virulence factors could not be confirmed. Though certain in vitro functions may be ascribed to these factors, their roles are not unique for S. suis, probably due to compensation by other factors. As such, variations and discrepancies in experimental design, including in vitro assays, cell lines, and animal models, are an important source of differences between results. Moreover, the use of different sequence types in this study demonstrates that the role attributed to a virulence factor may vary according to the S. suis serotype 2 strain background. Consequently, it is necessary to establish standard experimental designs according to the experiment and purpose in order to facilitate comparison between laboratories. Alongside, studies should include strains of diverse origins in order to prevent erroneous and biased conclusions that could affect future studies. PMID:28753679

  20. Integrating Survey and Molecular Approaches to Better Understand Wildlife Disease Ecology

    PubMed Central

    Cowled, Brendan D.; Ward, Michael P.; Laffan, Shawn W.; Galea, Francesca; Garner, M. Graeme; MacDonald, Anna J.; Marsh, Ian; Muellner, Petra; Negus, Katherine; Quasim, Sumaiya; Woolnough, Andrew P.; Sarre, Stephen D.

    2012-01-01

    Infectious wildlife diseases have enormous global impacts, leading to human pandemics, global biodiversity declines and socio-economic hardship. Understanding how infection persists and is transmitted in wildlife is critical for managing diseases, but our understanding is limited. Our study aim was to better understand how infectious disease persists in wildlife populations by integrating genetics, ecology and epidemiology approaches. Specifically, we aimed to determine whether environmental or host factors were stronger drivers of Salmonella persistence or transmission within a remote and isolated wild pig (Sus scrofa) population. We determined the Salmonella infection status of wild pigs. Salmonella isolates were genotyped and a range of data was collected on putative risk factors for Salmonella transmission. We a priori identified several plausible biological hypotheses for Salmonella prevalence (cross sectional study design) versus transmission (molecular case series study design) and fit the data to these models. There were 543 wild pig Salmonella observations, sampled at 93 unique locations. Salmonella prevalence was 41% (95% confidence interval [CI]: 37–45%). The median Salmonella DICE coefficient (or Salmonella genetic similarity) was 52% (interquartile range [IQR]: 42–62%). Using the traditional cross sectional prevalence study design, the only supported model was based on the hypothesis that abundance of available ecological resources determines Salmonella prevalence in wild pigs. In the molecular study design, spatial proximity and herd membership as well as some individual risk factors (sex, condition score and relative density) determined transmission between pigs. Traditional cross sectional surveys and molecular epidemiological approaches are complementary and together can enhance understanding of disease ecology: abundance of ecological resources critical for wildlife influences Salmonella prevalence, whereas Salmonella transmission is driven by local spatial, social, density and individual factors, rather than resources. This enhanced understanding has implications for the control of diseases in wildlife populations. Attempts to manage wildlife disease using simplistic density approaches do not acknowledge the complexity of disease ecology. PMID:23071552

  1. Leadership-Driven Anger Management Groups for Adolescents: Do They Really Work?

    ERIC Educational Resources Information Center

    Burt, Isaac

    2018-01-01

    This study investigated a current trend in anger-management groups labeled as leadership development. The goal of the investigation was to determine if leadership is a critical factor in working with angry youth. A total of 52 middle school-aged adolescents from 2 schools served as participants. Of those, 18 participants received a strength-based,…

  2. Examining a Proposed Job Retention Model for Adult Workers with Mental Retardation

    ERIC Educational Resources Information Center

    Fornes, Sandra L.

    2008-01-01

    This research provides an analysis of factors predicting job retention (JR), job satisfaction (JS), and job performance (JP) of workers with mental retardation (MR). The findings highlight self-determination as a critical skill in influencing three important employee's outcomes, JR, JS, and JP. The intent of the study was to develop job retention…

  3. Habitat associations of the sagebrush lizard (Sceloporus graciosus): Potential responses of an ectotherm to ponderosa pine forest restoration treatments

    Treesearch

    Shawn C. Knox; Carol Chambers; Stephen S. Germaine

    2001-01-01

    Little is known about the response of ectotherms to ponderosa pine (Pinus ponderosa) restoration treatments. The ambient body temperature of an ectotherm affects its physiology, development, and behavior. Microhabitat availability and heterogeneity are critical factors in determining which thermoregulation choices are available to a terrestrial ectotherm (Stevenson...

  4. A critical evaluation of the insect body size model and causes of metamorphosis in solitary bees

    USDA-ARS?s Scientific Manuscript database

    The insect body size model posits that adult size is determined by growth rate and the duration of growth during the larval stage of development. Within the model, growth rate is regulated by many mechanistic elements that are influenced by both internal and external factors. However, the duration o...

  5. Communication and Other Critical Predictors of Orientation to Change: A Multivariate Analysis.

    ERIC Educational Resources Information Center

    Edeani, David O.

    A study was conducted to examine the contributions to the determination of individuals' orientation to change made by such factors as the individuals' demographic, social structural, personality, and cognitive characteristics. Data were collected in a field sample of 159 adult residents of New Athens, Illinois, a town of 2,000 inhabitants near…

  6. Factors that Affect Mathematics-Science (MS) Scores in the Secondary Education Institutional Exam: An Application of Structural Equation Modeling

    ERIC Educational Resources Information Center

    Yavuz, Mustafa

    2009-01-01

    Discovering what determines students' success in the Secondary Education Institutional Exam is very important to parents and it is also critical for students, teachers, directors, and researchers. Research was carried out by studying the related literature and structural equation modeling techniques. A structural model was created that consisted…

  7. Critical aspects for the reliable headspace analysis of plants cultivated in vitro.

    PubMed

    Maes, K; Vercammen, J; Pham-Tuan, H; Sandra, P; Debergh, P C

    2001-01-01

    Various factors controlling the recoveries of volatile organic compounds in vitro headspace analysis of tomato plants (Lycopersicon esculentum Mill. 'Moneymaker'), sampled using solid phase micro-extraction, were evaluated and optimised. The variations in composition of the headspaces were determined as a function of time, and following in vitro wounding of the plant.

  8. Venous Return and Clinical Hemodynamics: How the Body Works during Acute Hemorrhage

    ERIC Educational Resources Information Center

    Shen, Tao; Baker, Keith

    2015-01-01

    Venous return is a major determinant of cardiac output. Adjustments within the venous system are critical for maintaining venous pressure during loss in circulating volume. This article reviews two factors that are thought to enable the venous system to compensate during acute hemorrhage: 1) changes in venous elastance and 2) mobilization of…

  9. Factors That Influence Information-Seeking Behavior: The Case of Greek Graduate Students

    ERIC Educational Resources Information Center

    Korobili, Stella; Malliari, Aphrodite; Zapounidou, Sofia

    2011-01-01

    The purpose of this survey is to determine the information-seeking behavior of graduate students of the Faculties of Philosophy (8 Schools) and Engineering (8 Schools) at the Aristotle University of Thessaloniki. Discipline did not seem to affect information-seeking behavior critically. The majority of the sample demonstrated a low to medium level…

  10. Bringing Vision to Practice: Planning and Provisioning the New Library Resource Center

    ERIC Educational Resources Information Center

    Wilson, Lisa

    2004-01-01

    The most critical factor in creating a successful school library is the development of a clear vision of the mission and functionality of this integral learning space. However, the process of bringing a vision to realization involves harsh realities and sensible planning. The budget will determine many purchasing decisions and therefore it is…

  11. School Motivation and High School Dropout: The Mediating Role of Educational Expectation

    ERIC Educational Resources Information Center

    Fan, Weihua; Wolters, Christopher A.

    2014-01-01

    Background: A good deal of evidence indicates that students' motivational beliefs and attitudes play a critical role in their academic success. Research studies on how motivational factors may help determine whether students remain in high school or drop out, however, are relatively few. More specifically, there is a lack of research…

  12. The Effect of School-Based Health Clinics on Teenage Pregnancy and Parenting Outcomes: An Integrated Literature Review

    ERIC Educational Resources Information Center

    Strunk, Julie A.

    2008-01-01

    Teenage pregnancy outcomes have become an increasing concern in the United States. Education and support of pregnant teens are critical factors that may determine good or poor pregnancy outcomes. Poor outcomes may include low birth weight, developmental delays, and poor academic performance. Although the number of teenagers experiencing pregnancy…

  13. Computer Attitude and eLearning Self-Efficacy of Undergraduate Students: Validating Potential Acceptance and Use of Online Learning Systems in Ghana

    ERIC Educational Resources Information Center

    Larbi-Apau, Josephine; Oti-Boadi, Mabel; Tetteh, Albert

    2018-01-01

    Both computer attitude and eLearning self-efficacy are critical complementary factors in determining confidence levels and behavioral belief systems, and can directly affect students' actions, performances and achievements. This study applied a multidimensional construct in validating computer attitude and eLearning self-efficacy of Psychology…

  14. The US Bayh-Dole Act and Revisionism Redux

    ERIC Educational Resources Information Center

    Bremer, Howard; Allen, Joseph; Latker, Norman J.

    2009-01-01

    In the past several years various published papers have questioned whether the Bayh-Dole Act of 1980 (The University and Small Business Patent Procedures Act) has in reality been a determining factor in promoting the transfer of technology from US universities, as has been credited to it. This paper responds to that criticism, presenting facts and…

  15. Optimization and development of stable w/o/w cosmetic multiple emulsions by means of the Quality by Design approach.

    PubMed

    Kovács, A; Erős, I; Csóka, I

    2016-04-01

    The aim of our present work was to develop stable water-in-oil-in-water (w/o/w) cosmetic multiple emulsions that are proper for cosmetic use and can also be applied on the skin as pharmaceutical vehicles by means of Quality by Design (QbD) concept. This product design concept consists of a risk assessment step and also the 'predetermination' of the critical material attributes and process parameters of a stable multiple emulsion system. We have set up the hypothesis that the stability of multiple emulsions can be improved by the development based on such systematic planning - making a map of critical product parameters - so their industrial usage can be increased. The risk assessment and the determination of critical physical-chemical stability parameters of w/o/w multiple emulsions to define critical control points were performed by means of quality tools and the leanqbd(™) (QbD Works LLC, Fremont, CA, U.S.A.) software. Critical materials and process parameters: Based on the results of preformulation experiments, three factors, namely entrapped active agent, preparation methodology and shear rate, were found to be highly critical factors for critical quality attributes (CQAs) and for stability, whereas the nature of oil was found a medium level risk factor. The results of the risk assessment are the following: (i) droplet structure and size distribution should be evaluated together to be able to predict the stability issues, (ii) the presence of entrapped active agents had a great impact on droplet structure, (iii) the viscosity curves represent the structural changes during storage, if the decrease in relative viscosity is >15% the emulsion disintegrates, and (iv) it is enough to use the shear rate between 34g and 116g relative centrifugal force (RCF). CQAs: By risk assessment, we discovered that four factors should be considered to be high-risk variables as compared to others: droplet size, droplet structure, viscosity and multiple character were found to be highly critical attributes. The preformulation experiment is the part of a development plan. On the basis of these results, the control strategy can be defined and a stable multiple emulsion can be ensured that meets the relevant stakeholders' quality expectations. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  16. Critical thinking skills of undergraduate nursing students: description and demographic predictors.

    PubMed

    Hunter, Sharyn; Pitt, Victoria; Croce, Nic; Roche, Jan

    2014-05-01

    This study investigated the critical thinking skills among undergraduate nursing students in Australia to obtain a profile and determine demographic predictors of critical thinking. There is universal agreement that being a critical thinker is an outcome requirement for many accreditation and registering nursing bodies. Most studies provide descriptive statistical information about critical thinking skills while some have studied the changes in critical thinking after an intervention. Limited research about factors that predict critical thinking skills is available. A cross-sectional descriptive study was conducted using convenience sampling. Two hundred and sixty-nine students were recruited across three years of an undergraduate programme in 2009. Most students' age ranged from under 20 to 34 years (58%), 87% were female, 91% were Australian and 23% of first and second year students had nursing associated experience external to the university. Data about critical thinking skills were collected via the Health Science Reasoning Test (HSRT). Linear regression analysis investigated the predictors of nursing students' critical thinking skills. The students in third year had a profile of critical thinking skills comparable with HSRT norms. Year of study predicted higher critical thinking scores for all domains (p<0.001) except the subscale, analysis. Nationality predicted higher scores for total CT skill scores (p<0.001) and subscales, inductive (p=0.001) and deductive reasoning (p=0.001). Nursing associated experience predicted higher scores for the subscale, analysis (p<0.001). Age and gender were not predictive. However, these demographic predictors only accounted for a small variance obtained for the domains of CT skills. An understanding of factors that predict nursing students' CT skills is required. Despite this study finding a number of significant predictors of nursing students' CT skills, there are others yet to be understood. Future research is recommended exploring explicit CT instructional approaches and nursing students' CT skills. © 2013 Elsevier Ltd. All rights reserved.

  17. Suspicion of respiratory tract infection with multidrug-resistant Enterobacteriaceae: epidemiology and risk factors from a Paediatric Intensive Care Unit.

    PubMed

    Renk, Hanna; Stoll, Lenja; Neunhoeffer, Felix; Hölzl, Florian; Kumpf, Matthias; Hofbeck, Michael; Hartl, Dominik

    2017-02-21

    Multidrug-resistant (MDR) infections are a serious concern for children admitted to the Paediatric Intensive Care Unit (PICU). Tracheal colonization with MDR Enterobacteriaceae predisposes to respiratory infection, but underlying risk factors are poorly understood. This study aims to determine the incidence of children with suspected infection during mechanical ventilation and analyses risk factors for the finding of MDR Enterobacteriaceae in tracheal aspirates. A retrospective single-centre analysis of Enterobacteriaceae isolates from the lower respiratory tract of ventilated PICU patients from 2005 to 2014 was performed. Resistance status was determined and clinical records were reviewed for potential risk factors. A classification and regression tree (CRT) to predict risk factors for infection with MDR Enterobacteriaceae was employed. The model was validated by simple and multivariable logistic regression. One hundred sixty-seven Enterobacteriaceae isolates in 123 children were identified. The most frequent isolates were Enterobacter spp., Klebsiella spp. and E.coli. Among these, 116 (69%) isolates were susceptible and 51 (31%) were MDR. In the CRT analysis, antibiotic exposure for ≥ 7 days and presence of gastrointestinal comorbidity were the most relevant predictors for an MDR isolate. Antibiotic exposure for ≥ 7 days was confirmed as a significant risk factor for infection with MDR Enterobacteriaceae by a multivariable logistic regression model. This study shows that critically-ill children with tracheal Enterobacteriaceae infection are at risk of carrying MDR isolates. Prior use of antibiotics for ≥ 7 days significantly increased the risk of finding MDR organisms in ventilated PICU patients with suspected infection. Our results imply that early identification of patients at risk, rapid microbiological diagnostics and tailored antibiotic therapy are essential to improve management of critically ill children infected with Enterobacteriaceae.

  18. Effects of the Application of the New Nuclear Data Library ENDF/B to the Criticality Analysis of AP1000

    NASA Astrophysics Data System (ADS)

    Kuntoro, Iman; Sembiring, T. M.; Susilo, Jati; Deswandri; Sunaryo, G. R.

    2018-02-01

    Calculations of criticality of the AP1000 core due to the use of new edition of nuclear data library namely ENDF/B-VII and ENDF/B-VII.1 have been done. This work is aimed to know the accuracy of ENDF/B-VII.1 compared to ENDF/B-VII and ENDF/B-VI.8. in determining the criticality parameter of AP1000. Analysis ws imposed to core at cold zero power (CZP) conditions. The calculations have been carried out by means of MCNP computer code for 3 dimension geometry. The results show that criticality parameter namely effective multiplication factor of the AP1000 core are higher than that ones resulted from ENDF/B-VI.8 with relative differences of 0.39% for application of ENDF/B-VII and of 0.34% for application of ENDF/B-VII.1.

  19. Fluid therapy in critically ill patients: perspectives from the right heart.

    PubMed

    Elbers, Paul; Rodrigus, Tim; Nossent, Esther; Malbrain, Manu L N G; Vonk-Noordegraaf, Anton

    2015-01-01

    As right heart function can affect outcome in the critically ill patient, a thorough understanding of factors determining right heart performance in health and disease is pivotal for the critical care physician. This review focuses on fluid therapy, which remains controversial in the setting of impending or overt right heart failure. In this context, we will attempt to elucidate which patients are likely to benefit from fluid administration and for which patients fluid therapy would likely be harmful. Following a general discussion of right heart function and failure, we specifically focus on important causes of right heart failure in the critically ill, i.e. sepsis induced myocardial dysfunction, the acute respiratory distress syndrome, acute pulmonary embolism and the effects of positive pressure ventilation. It is argued that fluid therapy should always be cautiously administered with the right heart in mind, which calls for close multimodal monitoring.

  20. The Chinese family-centered care survey for adult intensive care unit: A psychometric study.

    PubMed

    Wang, Wen-Ling; Feng, Jui-Ying; Wang, Chi-Jen; Chen, Jing-Huei

    2016-02-01

    This study aimed to develop a family-centered care survey for Chinese adult intensive care units and to establish the survey's psychometric properties. Family-centered care (FCC) is widely recognized as an ideal model of care. Few studies have explored FCC perceptions among family members of adult critical care patients in Asian countries, and no Chinese FCC measurement has been developed. An English version of the 3-factor family-centered care survey for adult intensive care units (FCCS-AICU) was translated into Chinese using a modified back translation procedure. Based on the literature review, two additional concepts, information and empowerment, were added to the Chinese FCCS-AICU. The psychometric properties of the Chinese FCCS-AICU were determined with 249 family members from a medical center in Taiwan and were tested for construct and convergent validity, and internal consistency. Both the monolingual and bilingual equivalence tests of the English and Chinese versions of the 3-factor FCCS-AICU were supported. Exploratory factor analysis supported the 5-factor structure of the Chinese FCCS-AICU with a total explained variance of 58.34%. The Chinese FCCS-AICU was correlated with the Chinese Critical Care Family Needs Inventory. Internal consistency, determined by Cronbach's α, for the overall scale was .94. The Chinese FCCS-AICU is a valid and reliable tool for measuring perceptions of FCC by family members of adult intensive care patients within Chinese-speaking communities. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. A fuzzy rumor spreading model based on transmission capacity

    NASA Astrophysics Data System (ADS)

    Zhang, Yi; Xu, Jiuping; Wu, Yue

    This paper proposes a rumor spreading model that considers three main factors: the event importance, event ambiguity, and the publics critical sense, each of which are defined by decision makers using linguistic descriptions and then transformed into triangular fuzzy numbers. To calculate the resultant force of these three factors, the transmission capacity and a new parameter category with fuzzy variables are determined. A rumor spreading model is then proposed which has fuzzy parameters rather than the fixed parameters in traditional models. As the proposed model considers the comprehensive factors affecting rumors from three aspects rather than examining special factors from a particular aspect. The proposed rumor spreading model is tested using different parameters for several different conditions on BA networks and three special cases are simulated. The simulation results for all three cases suggested that events of low importance, those that are only clarifying facts, and those that are strongly critical do not result in rumors. Therefore, the model assessment results were proven to be in agreement with reality. Parameters for the model were then determined and applied to an analysis of the 7.23 Yong-Wen line major transportation accident (YWMTA). When the simulated data were compared with the real data from this accident, the results demonstrated that the interval for the rumor spreading key point in the model was accurate, and that the key point for the YWMTA rumor spread fell into the range estimated by the model.

  2. Analysis of the Survival of Children Under Five in Indonesia and Associated Factors

    NASA Astrophysics Data System (ADS)

    Nur Islami Warrohmah, Annisa; Maniar Berliana, Sarni; Nursalam, Nursalam; Efendi, Ferry; Haryanto, Joni; Has, Eka Misbahatul M.; Ulfiana, Elida; Dwi Wahyuni, Sylvia

    2018-02-01

    The under-five mortality rate (U5MR) remains a challenge for developing nations, including Indonesia. This study aims to assess the key factors associated with mortality of Indonesian infants using survival analysis. Data taken from 14,727 live-born infants (2007-2012) was examined from the nationally representative Indonesian Demographic Health Survey. The Weibull hazard model was performed to analyse the socioeconomic status and related determinants of infant mortality. The findings indicated that mother factors (education, working status, autonomy, economic status, maternal age at birth, birth interval, type of births, complications, history of previous mortality, breastfeeding, antenatal care and place of delivery); infant factors (birth size); residence; and environmental conditions were associated with the childhood mortality. Rural or urban residence was an important determining factor of infant mortality. For example, considering the factor of a mother’s education, rural educated mothers had a significant association with the survival of their infants. In contrast, there was no significant association between urban educated mothers and their infants’ mortality. The results showed obvious contextual differences which determine the childhood mortality. Socio-demographic and economic factors remain critical in determining the death of infants. This study provides evidence for designing targeted interventions, as well as suggesting specific needs based on the population’s place of residence, in the issue of U5MR. Further interventions should also consider other identified variables while developing programmes to address infant’s needs.

  3. A socio-environmental monitoring system for a UNESCO biosphere reserve.

    PubMed

    Lowell, Kim

    2017-11-03

    To identify potentially critical changes in an area's ongoing ability to produce multiple ecosystem services, a monitoring system was designed and implemented for the Mornington Peninsula and Westernport Biosphere Reserve in southeast Australia. The system is underpinned by an "environmental vital signs" (EVS) approach that was adopted to provide early warning of critical changes in human and natural characteristics of the area. The six themes monitored are non-coastal water, land including vegetation, biodiversity, natural heritage, built environment (including human population and economic activity), and coasts. These are monitored for the entire area, and each of its five constituent town council areas. After a critical change in any of these is identified, further investigation is required to identify causal factors and, if required, determine an appropriate response. The system relies on data available from external (third-party) organisations to monitor the natural and human characteristics of the area that were important in its designation as a UNESCO biosphere reserve. Strengths and weaknesses associated with the use of third-party data are discussed. These include adoption of baseline years and data reporting periods for different factors, costs, and data quality.

  4. The Critical Success Factor Method: Establishing a Foundation for Enterprise Security Management

    DTIC Science & Technology

    2004-07-01

    importance.                                                                13  SWOT   analysis  is a commonly used strategic planning technique.  It identifies...24  Figure 11:  Relationship Between Enterprise and Operational Unit CSFs ............... 28  Figure 12:  Affinity  Analysis  for Determining...ISRM Scope ....................................... 36  Figure 13:  Affinity  Analysis  for Determining Critical Assets

  5. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis.

    PubMed

    Camacho, Ana María; Veganzones, Mariano; Claver, Juan; Martín, Francisco; Sevilla, Lorenzo; Sebastián, Miguel Ángel

    2016-09-01

    Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE) simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS₂ grease, silicone oil, and copper paste) to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs). The results show that for small reductions ( r h < 20%), the conventional RCT can be applied because the tribological conditions remain similar. For large reductions ( r h > 20%), it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered.

  6. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis

    PubMed Central

    Camacho, Ana María; Veganzones, Mariano; Claver, Juan; Martín, Francisco; Sevilla, Lorenzo; Sebastián, Miguel Ángel

    2016-01-01

    Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE) simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS2 grease, silicone oil, and copper paste) to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs). The results show that for small reductions (rh < 20%), the conventional RCT can be applied because the tribological conditions remain similar. For large reductions (rh > 20%), it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered. PMID:28773868

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

    Ackerman, G; Bale, J; Moran, K

    Certain types of infrastructure--critical infrastructure (CI)--play vital roles in underpinning our economy, security, and way of life. One particular type of CI--that relating to chemicals--constitutes both an important element of our nation's infrastructure and a particularly attractive set of potential targets. This is primarily because of the large quantities of toxic industrial chemicals (TICs) it employs in various operations and because of the essential economic functions it serves. This study attempts to minimize some of the ambiguities that presently impede chemical infrastructure threat assessments by providing new insight into the key motivational factors that affect terrorist organizations propensity to attackmore » chemical facilities. Prepared as a companion piece to the Center for Nonproliferation Studies August 2004 study--''Assessing Terrorist Motivations for Attacking Critical Infrastructure''--it investigates three overarching research questions: (1) why do terrorists choose to attack chemical-related infrastructure over other targets; (2) what specific factors influence their target selection decisions concerning chemical facilities; and (3) which, if any, types of groups are most inclined to attack chemical infrastructure targets? The study involved a multi-pronged research design, which made use of four discrete investigative techniques to answer the above questions as comprehensively as possible. These include: (1) a review of terrorism and threat assessment literature to glean expert consensus regarding terrorist interest in targeting chemical facilities; (2) the preparation of case studies to help identify internal group factors and contextual influences that have played a significant role in leading some terrorist groups to attack chemical facilities; (3) an examination of data from the Critical Infrastructure Terrorist Incident Catalog (CrITIC) to further illuminate the nature of terrorist attacks against chemical facilities to date; and (4) the refinement of the DECIDe--the Determinants Effecting Critical Infrastructure Decisions--analytical framework to make the factors and dynamics identified by the study more ''usable'' in future efforts to assess terrorist intentions to target chemical-related infrastructure.« less

  8. Critical behaviour and vapour-liquid coexistence of 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ionic liquids via Monte Carlo simulations.

    PubMed

    Rai, Neeraj; Maginn, Edward J

    2012-01-01

    Atomistic Monte Carlo simulations are used to compute vapour-liquid coexistence properties of a homologous series of [C(n)mim][NTf2] ionic liquids, with n = 1, 2, 4, 6. Estimates of the critical temperatures range from 1190 K to 1257 K, with longer cation alkyl chains serving to lower the critical temperature. Other quantities such as critical density, critical pressure, normal boiling point, and accentric factor are determined from the simulations. Vapour pressure curves and the temperature dependence of the enthalpy of vapourisation are computed and found to have a weak dependence on the length of the cation alkyl chain. The ions in the vapour phase are predominately in single ion pairs, although a significant number of ions are found in neutral clusters of larger sizes as temperature is increased. It is found that previous estimates of the critical point obtained from extrapolating experimental surface tension data agree reasonably well with the predictions obtained here, but group contribution methods and primitive models of ionic liquids do not capture many of the trends observed in the present study

  9. Deletion of the transforming growth factor β receptor type II gene in articular chondrocytes leads to a progressive osteoarthritis-like phenotype in mice.

    PubMed

    Shen, Jie; Li, Jia; Wang, Baoli; Jin, Hongting; Wang, Meina; Zhang, Yejia; Yang, Yunzhi; Im, Hee-Jeong; O'Keefe, Regis; Chen, Di

    2013-12-01

    While transforming growth factor β (TGFβ) signaling plays a critical role in chondrocyte metabolism, the TGFβ signaling pathways and target genes involved in cartilage homeostasis and the development of osteoarthritis (OA) remain unclear. Using an in vitro cell culture method and an in vivo mouse genetic approach, we undertook this study to investigate TGFβ signaling in chondrocytes and to determine whether Mmp13 and Adamts5 are critical downstream target genes of TGFβ signaling. TGFβ receptor type II (TGFβRII)-conditional knockout (KO) (TGFβRII(Col2ER)) mice were generated by breeding TGFβRII(flox/flox) mice with Col2-CreER-transgenic mice. Histologic, histomorphometric, and gene expression analyses were performed. In vitro TGFβ signaling studies were performed using chondrogenic rat chondrosarcoma cells. To determine whether Mmp13 and Adamts5 are critical downstream target genes of TGFβ signaling, TGFβRII/matrix metalloproteinase 13 (MMP-13)- and TGFβRII/ADAMTS-5-double-KO mice were generated and analyzed. Inhibition of TGFβ signaling (deletion of the Tgfbr2 gene in chondrocytes) resulted in up-regulation of Runx2, Mmp13, and Adamts5 expression in articular cartilage tissue and progressive OA development in TGFβRII(Col2ER) mice. Deletion of the Mmp13 or Adamts5 gene significantly ameliorated the OA-like phenotype induced by the loss of TGFβ signaling. Treatment of TGFβRII(Col2ER) mice with an MMP-13 inhibitor also slowed OA progression. Mmp13 and Adamts5 are critical downstream target genes involved in the TGFβ signaling pathway during the development of OA. Copyright © 2013 by the American College of Rheumatology.

  10. Division of labour between Myc and G1 cyclins in cell cycle commitment and pace control.

    PubMed

    Dong, Peng; Maddali, Manoj V; Srimani, Jaydeep K; Thélot, François; Nevins, Joseph R; Mathey-Prevot, Bernard; You, Lingchong

    2014-09-01

    A body of evidence has shown that the control of E2F transcription factor activity is critical for determining cell cycle entry and cell proliferation. However, an understanding of the precise determinants of this control, including the role of other cell-cycle regulatory activities, has not been clearly defined. Here, recognizing that the contributions of individual regulatory components could be masked by heterogeneity in populations of cells, we model the potential roles of individual components together with the use of an integrated system to follow E2F dynamics at the single-cell level and in real time. These analyses reveal that crossing a threshold amplitude of E2F accumulation determines cell cycle commitment. Importantly, we find that Myc is critical in modulating the amplitude, whereas cyclin D/E activities have little effect on amplitude but do contribute to the modulation of duration of E2F activation, thereby affecting the pace of cell cycle progression.

  11. Mutant KRAS as a critical determinant of the therapeutic response of colorectal cancer

    PubMed Central

    Knickelbein, Kyle; Zhang, Lin

    2014-01-01

    Mutations in the KRAS oncogene represent one of the most prevalent genetic alterations in colorectal cancer (CRC), the third leading cause of cancer-related death in the US. In addition to their well-characterized function in driving tumor progression, KRAS mutations have been recognized as a critical determinant of the therapeutic response of CRC. Recent studies demonstrate that KRAS-mutant tumors are intrinsically insensitive to clinically-used epidermal growth factor receptor (EGFR) targeting antibodies, including cetuximab and panitumumab. Acquired resistance to the anti-EGFR therapy was found to be associated with enrichment of KRAS-mutant tumor cells. However, the underlying molecular mechanism of mutant-KRAS-mediated therapeutic resistance has remained unclear. Despite intensive efforts, directly targeting mutant KRAS has been largely unsuccessful. This review summarizes the recent advances in understanding the biological function of KRAS mutations in determining the therapeutic response of CRC, highlighting several recently developed agents and strategies for targeting mutant KRAS, such as synthetic lethal interactions. PMID:25815366

  12. Characterizing air quality data from complex network perspective.

    PubMed

    Fan, Xinghua; Wang, Li; Xu, Huihui; Li, Shasha; Tian, Lixin

    2016-02-01

    Air quality depends mainly on changes in emission of pollutants and their precursors. Understanding its characteristics is the key to predicting and controlling air quality. In this study, complex networks were built to analyze topological characteristics of air quality data by correlation coefficient method. Firstly, PM2.5 (particulate matter with aerodynamic diameter less than 2.5 μm) indexes of eight monitoring sites in Beijing were selected as samples from January 2013 to December 2014. Secondly, the C-C method was applied to determine the structure of phase space. Points in the reconstructed phase space were considered to be nodes of the network mapped. Then, edges were determined by nodes having the correlation greater than a critical threshold. Three properties of the constructed networks, degree distribution, clustering coefficient, and modularity, were used to determine the optimal value of the critical threshold. Finally, by analyzing and comparing topological properties, we pointed out that similarities and difference in the constructed complex networks revealed influence factors and their different roles on real air quality system.

  13. Use of Bioclimatic Factors to Determine Potential Niche of Vaccinia Virus, an Emerging and Zoonotic Pathogen

    NASA Astrophysics Data System (ADS)

    Quiner, C. A.; Nakazawa, Y.

    2017-12-01

    Emerging and understudied pathogens often lack information that most commonly used analytical tools require, such as negative controls or baseline data making public health control of emerging pathogens challenging. In lieu of opportunities to collect more data from larger outbreaks or formal epidemiological studies, new analytical strategies, merging case data with publically available datasets, can be used to understand transmission patterns and drivers of disease emergence. Zoonotic infections with Vaccinia virus (VACV) were first reported in Brazil in 1999, VACV is an emerging zoonotic Orthopoxvirus, which primarily infects dairy cattle and farmers in close contact with infected cows. Prospective studies of emerging pathogens could provide critical data that would inform public health planning and response to outbreaks. By using the location of 87-recorded outbreaks and publicly available bioclimatic data we demonstrate one such approach. Using an Ecological Niche Model (ENM), we identify the environmental conditions under which VACV outbreaks have occurred, and determine additional locations in two affected South American countries that may be susceptible to transmission. Further, we show how suitability for the virus responds to different levels of various environmental factors and highlight the most important climatic factors in determining its transmission. The final ENM predicted all areas where Brazilian outbreaks occurred, two out of five Colombian outbreaks and identified new regions within Brazil that are suitable for transmission based on bioclimatic factors. Further, the most important factors in determining transmission suitability are precipitation of the wettest quarter, annual precipitation, mean temperature of the coldest quarter and mean diurnal range. The analyses here provide a means by which to study patterns of an emerging infectious disease, and regions that are potentially at risk for it, in spite of the paucity of critical data. Policy and methods for the control of infectious diseases often use a reactionary model, addressing diseases only after significant impact on human health has ensued. Here, we provide a means to predict where the disease is likely to appear, providing a map for directed intervention.

  14. Critical assessment of precracked specimen configuration and experimental test variables for stress corrosion testing of 7075-T6 aluminum alloy plate

    NASA Technical Reports Server (NTRS)

    Domack, M. S.

    1985-01-01

    A research program was conducted to critically assess the effects of precracked specimen configuration, stress intensity solutions, compliance relationships and other experimental test variables for stress corrosion testing of 7075-T6 aluminum alloy plate. Modified compact and double beam wedge-loaded specimens were tested and analyzed to determine the threshold stress intensity factor and stress corrosion crack growth rate. Stress intensity solutions and experimentally determined compliance relationships were developed and compared with other solutions available in the literature. Crack growth data suggests that more effective crack length measurement techniques are necessary to better characterize stress corrosion crack growth. Final load determined by specimen reloading and by compliance did not correlate well, and was considered a major source of interlaboratory variability. Test duration must be determined systematically, accounting for crack length measurement resolution, time for crack arrest, and experimental interferences. This work was conducted as part of a round robin program sponsored by ASTM committees G1.06 and E24.04 to develop a standard test method for stress corrosion testing using precracked specimens.

  15. DIPPR Project 871 For 1995 - Thermodynamic Properties and Ideal-Gas Enthalpies of Formation for Methyl Benzoate, Ethyl Benzoate, (R)-(+)-Limonene, Tert-Amyl Methyl Ether, Trans-Crotonaldehyde, and

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

    Steele, W.V.

    2002-07-01

    Ideal-gas enthalpies of formation of methyl benzoate, ethyl benzoate, (R)-(+)-limonene, tert-amyl methyl ether, trans-crotonaldehyde, and diethylene glycol are reported. The standard energy of combustion and hence standard enthalpy of formation of each compound in the liquid phase has been measured using an oxygen rotating-bomb calorimeter without rotation. Vapor pressures were measured to a pressure limit of 270 kPa or the lower decomposition point for each of the six compounds using a twin ebulliometric apparatus. Liquid-phase densities along the saturation line were measured for each compound over a range of temperature (ambient to a maximum of 548 K). A differential scanningmore » calorimeter was used to measure two-phase (liquid + vapor) heat capacities for each compound in the temperature region ambient to the critical temperature or lower decomposition point. For methyl benzoate and tert-amyl methyl ether, critical temperatures and critical densities were determined from the DSC results and corresponding critical pressures derived from the fitting procedures. Fitting procedures were used to derive critical temperatures, critical pressures, and critical densities for each of the remaining compounds. The results of the measurements were combined to derive a series of thermophysical properties including critical temperature, critical density, critical pressure, acentric factor, enthalpies of vaporization (restricted to within {+-}50 K of the temperature region of the experimentally determined vapor pressures), and heat capacities along the saturation line. Wagner-type vapor-pressure equations were derived for each compound. All measured and derived values were compared with those obtained in a search of the literature. Recommended critical parameters are listed for each of the compounds studied. Group-additivity parameters, useful in the application of the Benson gas-phase group-contribution correlations, were derived.« less

  16. Critical habitat for threatened and endangered species: how should the economic costs be evaluated?

    PubMed

    Plantinga, Andrew J; Helvoigt, Ted L; Walker, Kirsten

    2014-02-15

    The designation of critical habitat is a feature of endangered species protection laws in many countries. Under the U.S. Endangered Species Act, economics cannot enter into decisions to list species as threatened or endangered, but can be considered when critical habitat is designated. Areas can be excluded from proposed critical habitat if the economic cost of including them is determined to exceed the benefits of inclusion, and exclusion would not result in extinction of the species. The economic analysis done to support critical habitat exclusions has been controversial, and the focus of much litigation. We evaluate a sample of these analyses, and discuss the exclusions that were made in each case. We discuss how the methodology used to measure economic costs of critical habitat has changed over time and provide a critique of these alternative methods. We find that the approach currently in use is sound from an economic perspective. Nevertheless, quantification of the costs of critical habitat faces numerous challenges, including great uncertainty about future events, questions about the appropriate scale for the analysis, and the need to account for complex market feedbacks and values of non-market goods. For the studies we reviewed, there was no evidence that the results of the economic analyses provided information that was useful for making decisions about exemptions from critical habitat designations. If economics is to play a meaningful role in determining endangered species protections, an alternative would be to allow listing decisions to be based on economic as well as biological factors, as is typical for species conservation laws in other countries. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Critical loads of nitrogen deposition and critical levels of atmospheric ammonia for mediterranean evergreen woodlands

    NASA Astrophysics Data System (ADS)

    Pinho, P.; Theobald, M. R.; Dias, T.; Tang, Y. S.; Cruz, C.; Martins-Loução, M. A.; Máguas, C.; Sutton, M.; Branquinho, C.

    2011-11-01

    Nitrogen (N) has emerged in recent years as a key factor associated with global changes, with impacts on biodiversity, ecosystems functioning and human health. In order to ameliorate the effects of excessive N, safety thresholds have been established, such as critical loads (deposition fluxes) and levels (concentrations). For Mediterranean ecosystems, few studies have been carried out to assess these parameters. Our objective was therefore to determine the critical loads of N deposition and long-term critical levels of atmospheric ammonia for Mediterranean evergreen woodlands. For that we have considered changes in epiphytic lichen communities, which have been shown to be one of the most sensitive to excessive N. Based on a classification of lichen species according to their tolerance to N we grouped species into response functional groups, which we used as a tool to determine the critical loads and levels. This was done under Mediterranean climate, in evergreen cork-oak woodlands, by sampling lichen functional diversity and annual atmospheric ammonia concentrations and modelling N deposition downwind from a reduced N source (a cattle barn). By modelling the highly significant relationship between lichen functional groups and N deposition, the critical load was estimated to be below 26 kg (N) ha-1 yr-1, which is within the upper range established for other semi-natural ecosystems. By modelling the highly significant relationship of lichen functional groups with annual atmospheric ammonia concentration, the critical level was estimated to be below 1.9 μg m-3, in agreement with recent studies for other ecosystems. Taking into account the high sensitivity of lichen communities to excessive N, these values should be taken into account in policies that aim at protecting Mediterranean woodlands from the initial effects of excessive N.

  18. Probabilistic low-rank factorization accelerates tensor network simulations of critical quantum many-body ground states.

    PubMed

    Kohn, Lucas; Tschirsich, Ferdinand; Keck, Maximilian; Plenio, Martin B; Tamascelli, Dario; Montangero, Simone

    2018-01-01

    We provide evidence that randomized low-rank factorization is a powerful tool for the determination of the ground-state properties of low-dimensional lattice Hamiltonians through tensor network techniques. In particular, we show that randomized matrix factorization outperforms truncated singular value decomposition based on state-of-the-art deterministic routines in time-evolving block decimation (TEBD)- and density matrix renormalization group (DMRG)-style simulations, even when the system under study gets close to a phase transition: We report linear speedups in the bond or local dimension of up to 24 times in quasi-two-dimensional cylindrical systems.

  19. Probabilistic low-rank factorization accelerates tensor network simulations of critical quantum many-body ground states

    NASA Astrophysics Data System (ADS)

    Kohn, Lucas; Tschirsich, Ferdinand; Keck, Maximilian; Plenio, Martin B.; Tamascelli, Dario; Montangero, Simone

    2018-01-01

    We provide evidence that randomized low-rank factorization is a powerful tool for the determination of the ground-state properties of low-dimensional lattice Hamiltonians through tensor network techniques. In particular, we show that randomized matrix factorization outperforms truncated singular value decomposition based on state-of-the-art deterministic routines in time-evolving block decimation (TEBD)- and density matrix renormalization group (DMRG)-style simulations, even when the system under study gets close to a phase transition: We report linear speedups in the bond or local dimension of up to 24 times in quasi-two-dimensional cylindrical systems.

  20. Factors confounding the assessment of reflection: a critical review

    PubMed Central

    2011-01-01

    Background Reflection on experience is an increasingly critical part of professional development and lifelong learning. There is, however, continuing uncertainty about how best to put principle into practice, particularly as regards assessment. This article explores those uncertainties in order to find practical ways of assessing reflection. Discussion We critically review four problems: 1. Inconsistent definitions of reflection; 2. Lack of standards to determine (in)adequate reflection; 3. Factors that complicate assessment; 4. Internal and external contextual factors affecting the assessment of reflection. Summary To address the problem of inconsistency, we identified processes that were common to a number of widely quoted theories and synthesised a model, which yielded six indicators that could be used in assessment instruments. We arrived at the conclusion that, until further progress has been made in defining standards, assessment must depend on developing and communicating local consensus between stakeholders (students, practitioners, teachers, supervisors, curriculum developers) about what is expected in exercises and formal tests. Major factors that complicate assessment are the subjective nature of reflection's content and the dependency on descriptions by persons being assessed about their reflection process, without any objective means of verification. To counter these validity threats, we suggest that assessment should focus on generic process skills rather than the subjective content of reflection and where possible to consider objective information about the triggering situation to verify described reflections. Finally, internal and external contextual factors such as motivation, instruction, character of assessment (formative or summative) and the ability of individual learning environments to stimulate reflection should be considered. PMID:22204704

  1. Perceptual load in different regions of the visual scene and its relevance for driving.

    PubMed

    Marciano, Hadas; Yeshurun, Yaffa

    2015-06-01

    The aim of this study was to better understand the role played by perceptual load, at both central and peripheral regions of the visual scene, in driving safety. Attention is a crucial factor in driving safety, and previous laboratory studies suggest that perceptual load is an important factor determining the efficiency of attentional selectivity. Yet, the effects of perceptual load on driving were never studied systematically. Using a driving simulator, we orthogonally manipulated the load levels at the road (central load) and its sides (peripheral load), while occasionally introducing critical events at one of these regions. Perceptual load affected driving performance at both regions of the visual scene. Critically, the effect was different for central versus peripheral load: Whereas load levels on the road mainly affected driving speed, load levels on its sides mainly affected the ability to detect critical events initiating from the roadsides. Moreover, higher levels of peripheral load impaired performance but mainly with low levels of central load, replicating findings with simple letter stimuli. Perceptual load has a considerable effect on driving, but the nature of this effect depends on the region of the visual scene at which the load is introduced. Given the observed importance of perceptual load, authors of future studies of driving safety should take it into account. Specifically, these findings suggest that our understanding of factors that may be relevant for driving safety would benefit from studying these factors under different levels of load at different regions of the visual scene. © 2014, Human Factors and Ergonomics Society.

  2. C5 nerve palsy after posterior reconstruction surgery: predictive risk factors of the incidence and critical range of correction for kyphosis.

    PubMed

    Kurakawa, Takuto; Miyamoto, Hiroshi; Kaneyama, Shuichi; Sumi, Masatoshi; Uno, Koki

    2016-07-01

    It has been reported that the incidence of post-operative segmental nerve palsy, such as C5 palsy, is higher in posterior reconstruction surgery than in conventional laminoplasty. Correction of kyphosis may be related to such a complication. The aim of this study was to elucidate the risk factors of the incidence of post-operative C5 palsy, and the critical range of sagittal realignment in posterior instrumentation surgery. Eighty-eight patients (mean age 64.0 years) were involved. The types of the disease were; 33 spondylosis with kyphosis, 27 rheumatoid arthritis, 17 athetoid cerebral palsy and 11 others. The patients were divided into two groups; Group P: patients with post-operative C5 palsy, and Group NP: patients without C5 palsy. The correction angle of kyphosis, and pre-operative diameter of C4/5 foramen on CT were evaluated between the two groups. Multivariate logistic regression analysis was used to determine the critical range of realignment and the risk factors affecting the incidence of post-operative C5 palsy. Seventeen (19.3 %) of the 88 patients developed C5 palsy. The correction angle of kyphosis in Group P (15.7°) was significantly larger than that in Group NP (4.5°). In Group P, pre-operative diameters of intervertebral foramen at C4/5 (3.2 mm) were significantly smaller than those in Group NP (4.1 mm). The multivariate analysis demonstrated that the risk factors were the correction angle and pre-operative diameter of the C4/5 intervertebral foramen. The logistic regression model showed a correction angle exceeding 20° was critical for developing the palsy when C4/5 foraminal diameter reaches 4.1 mm, and there is a higher risk when the C4/5 foraminal diameter is less than 2.7 mm regardless of any correction. This study has indicated the risk factors of post-operative C5 palsy and the critical range of realignment of the cervical spine after posterior instrumented surgery.

  3. Illegal psychoactive substance consumption amongst older schoolchildren in the city of Tunja, Colombia.

    PubMed

    Ospina-Díaz, Juan M; Herrera-Amaya, Giomar M; Manrique-Abril, Fred G

    2012-06-01

    Assessing lifetime prevalence of illegal substance use and accessibility to such substances. Determining risk factors and the protective factors linked to them. This was a cross-sectional study using descriptive and bivariate analysis. A survey was applied to 1,515 students from 8th to 11th grades in the city's schools, ages ranging from 12 to 18. An increase in lifetime prevalence and lower age for consumption onset were found. The main risk factors were determined to be academic environment and attitudes towards school authorities, linked to recreational and sports groups without control by elders, gang membership and engaging in risky and dangerous activities. The results showed the need for a critical review of current promotion and prevention strategies aimed at controlling the use of psychoactive substances amongst children and adolescents, according to the current reality of trafficking and domestic consumption in Colombia.

  4. Determining the nuclear data uncertainty on MONK10 and WIMS10 criticality calculations

    NASA Astrophysics Data System (ADS)

    Ware, Tim; Dobson, Geoff; Hanlon, David; Hiles, Richard; Mason, Robert; Perry, Ray

    2017-09-01

    The ANSWERS Software Service is developing a number of techniques to better understand and quantify uncertainty on calculations of the neutron multiplication factor, k-effective, in nuclear fuel and other systems containing fissile material. The uncertainty on the calculated k-effective arises from a number of sources, including nuclear data uncertainties, manufacturing tolerances, modelling approximations and, for Monte Carlo simulation, stochastic uncertainty. For determining the uncertainties due to nuclear data, a set of application libraries have been generated for use with the MONK10 Monte Carlo and the WIMS10 deterministic criticality and reactor physics codes. This paper overviews the generation of these nuclear data libraries by Latin hypercube sampling of JEFF-3.1.2 evaluated data based upon a library of covariance data taken from JEFF, ENDF/B, JENDL and TENDL evaluations. Criticality calculations have been performed with MONK10 and WIMS10 using these sampled libraries for a number of benchmark models of fissile systems. Results are presented which show the uncertainty on k-effective for these systems arising from the uncertainty on the input nuclear data.

  5. Genome-wide Determinants of Proviral Targeting, Clonal Abundance and Expression in Natural HTLV-1 Infection

    PubMed Central

    Melamed, Anat; Laydon, Daniel J.; Gillet, Nicolas A.; Tanaka, Yuetsu; Taylor, Graham P.; Bangham, Charles R. M.

    2013-01-01

    The regulation of proviral latency is a central problem in retrovirology. We postulate that the genomic integration site of human T lymphotropic virus type 1 (HTLV-1) determines the pattern of expression of the provirus, which in turn determines the abundance and pathogenic potential of infected T cell clones in vivo. We recently developed a high-throughput method for the genome-wide amplification, identification and quantification of proviral integration sites. Here, we used this protocol to test two hypotheses. First, that binding sites for transcription factors and chromatin remodelling factors in the genome flanking the proviral integration site of HTLV-1 are associated with integration targeting, spontaneous proviral expression, and in vivo clonal abundance. Second, that the transcriptional orientation of the HTLV-1 provirus relative to that of the nearest host gene determines spontaneous proviral expression and in vivo clonal abundance. Integration targeting was strongly associated with the presence of a binding site for specific host transcription factors, especially STAT1 and p53. The presence of the chromatin remodelling factors BRG1 and INI1 and certain host transcription factors either upstream or downstream of the provirus was associated respectively with silencing or spontaneous expression of the provirus. Cells expressing HTLV-1 Tax protein were significantly more frequent in clones of low abundance in vivo. We conclude that transcriptional interference and chromatin remodelling are critical determinants of proviral latency in natural HTLV-1 infection. PMID:23555266

  6. Argon-oxygen atmospheric pressure plasma treatment on carbon fiber reinforced polymer for improved bonding

    NASA Astrophysics Data System (ADS)

    Chartosias, Marios

    Acceptance of Carbon Fiber Reinforced Polymer (CFRP) structures requires a robust surface preparation method with improved process controls capable of ensuring high bond quality. Surface preparation in a production clean room environment prior to applying adhesive for bonding would minimize risk of contamination and reduce cost. Plasma treatment is a robust surface preparation process capable of being applied in a production clean room environment with process parameters that are easily controlled and documented. Repeatable and consistent processing is enabled through the development of a process parameter window utilizing techniques such as Design of Experiments (DOE) tailored to specific adhesive and substrate bonding applications. Insight from respective plasma treatment Original Equipment Manufacturers (OEMs) and screening tests determined critical process factors from non-factors and set the associated factor levels prior to execution of the DOE. Results from mode I Double Cantilever Beam (DCB) testing per ASTM D 5528 [1] standard and DOE statistical analysis software are used to produce a regression model and determine appropriate optimum settings for each factor.

  7. Predictors of School Garden Integration: Factors Critical to Gardening Success in New York City.

    PubMed

    Burt, Kate Gardner; Burgermaster, Marissa; Jacquez, Raquel

    2018-03-01

    The purpose of this study was to determine the level of integration of school gardens and identify factors that predict integration. 211 New York City schools completed a survey that collected demographic information and utilized the School Garden Integration Scale. A mean garden integration score was calculated, and multiple regression analysis was conducted to determine independent predictors of integration and assess relationships between individual integration characteristics and budget. The average integration score was 34.1 (of 57 points) and ranged from 8 to 53. Operating budget had significant influence on integration score, controlling for all other factors ( p < .0001). Partner organizations, evaluation/feedback, planning the physical space, and characteristics of the physical space were positively and significantly related to budget. The results of this study indicate that any garden can become well integrated, as budget is a modifiable factor. When adequate funding is secured, a well-integrated garden may be established with proper planning and sound implementation.

  8. Bending strength model for internal spur gear teeth

    NASA Technical Reports Server (NTRS)

    Savage, Michael; Rubadeux, K. L.; Coe, H. H.

    1995-01-01

    Internal spur gear teeth are normally stronger than pinion teeth of the same pitch and face width since external teeth are smaller at the base. However, ring gears which are narrower have an unequal addendum or are made of a material with a lower strength than that of the meshing pinion may be loaded more critically in bending. In this study, a model for the bending strength of an internal gear tooth as a function of the applied load pressure angle is presented which is based on the inscribed Lewis constant strength parabolic beam. The bending model includes a stress concentration factor and an axial compression term which are extensions of the model for an external gear tooth. The geometry of the Lewis factor determination is presented, the iteration to determine the factor is described, and the bending strength J factor is compared to that of an external gear tooth. This strength model will assist optimal design efforts for unequal addendum gears and gears of mixed materials.

  9. Elastic interactions between single microcrack and single osteon microstructure of human femur cortical bone

    NASA Astrophysics Data System (ADS)

    Mansor, N. N.; Daud, R.; Basaruddin, K. S.; Mat, F.; Bajuri, Y.; Ariffin, A. K.

    2017-09-01

    Inmultiscale Haversian system of cortical bone fracture, a homogenous bone modeling consideration is limited to only one Young modulus was significant for each cortex without having any constituents in that bone. A two dimension model of human femur cortical bone is presented by considering the anatomical positions of four cortices, e.g anterior, posterior, medial and lateral. The Haversian system is modeled under tensile loading by considering the interstitial matrix, osteon and cement line mechanical properties. The interaction between single microcrack and single osteon is evaluated using linear elastic fracture mechanics theory, and was determined using of stress intensity factor, strain energy release rate, and the critical stress intensity factor and critical strain energy release rate parameter. The results indicate that the medial cortex has the highest SIFs while the lowest was posterior cortex. The Young modulus of material was greatly influence the fracture parameters. More stiff the material, the SIF was reduced.

  10. Mechanisms of Cytotoxicity of the AIDS Virus.

    DTIC Science & Technology

    1991-10-10

    lentiviruses causes immunosuppression in cats ( feline immunodeficiency virus) (Pederson et al., 1987; Luciw et al., 1989), sheep (visna virus) (Haas et...determinant within the human immunodeficiency virus 1 surface envelope glycoprotein critical for productive infection of primary monocytes. 4. Simian... Immunodeficiency Virus Negative Factor Suppresses the Level of Viral mRNA in COS cells 5. Protein N-myristoylation/AIDS/fatty acid analogs 6. Functional

  11. The Determinants of Students' Perceived Learning Outcomes and Satisfaction in University Online Education: An Update

    ERIC Educational Resources Information Center

    Eom, Sean B.; Ashill, Nicholas

    2016-01-01

    A stream of research over the past decade that identifies predictors of e-learning success suggests that there are several critical success factors (CSFs) that must be managed effectively to fully realize promise for e-learning. Grounded in constructivist learning theories, this study advances previous work on CSFs in university online education.…

  12. Choice of Target Population Weights in Rater Comparability Scoring and Equating. Research Report. ETS RR-13-03

    ERIC Educational Resources Information Center

    Puhan, Gautam

    2013-01-01

    The purpose of this study was to demonstrate that the choice of sample weights when defining the target population under poststratification equating can be a critical factor in determining the accuracy of the equating results under a unique equating scenario, known as "rater comparability scoring and equating." The nature of data…

  13. Poverty and elimination of urban health disparities: challenge and opportunity.

    PubMed

    Thomas, Stephen B; Quinn, Sandra Crouse

    2008-01-01

    The aim of this article is to examine the intersection of race and poverty, two critical factors fueling persistent racial and ethnic health disparities among urban populations. From the morass of social determinants that shape the health of racial and ethnic communities in our urban centers, we will offer promising practices and potential solutions to eliminating racial and ethnic health disparities.

  14. Relationships between the Family Environment and School-Based Obesity Prevention Efforts: Can School Programs Help Adolescents Who Are Most in Need?

    ERIC Educational Resources Information Center

    Bauer, K. W.; Neumark-Sztainer, D.; Hannan, P. J.; Fulkerson, J. A.; Story, M.

    2011-01-01

    Identifying factors that contribute to students' behavior and weight improvements during school-based obesity prevention interventions is critical for the development of effective programs. The current study aims to determine whether the support and resources that adolescent girls received from their families were associated with improvements in…

  15. Population Connectivity Measures of Fishery-Targeted Coral Reef Species to Inform Marine Reserve Network Design in Fiji.

    PubMed

    Eastwood, Erin K; López, Elora H; Drew, Joshua A

    2016-01-25

    Coral reef fish serve as food sources to coastal communities worldwide, yet are vulnerable to mounting anthropogenic pressures like overfishing and climate change. Marine reserve networks have become important tools for mitigating these pressures, and one of the most critical factors in determining their spatial design is the degree of connectivity among different populations of species prioritized for protection. To help inform the spatial design of an expanded reserve network in Fiji, we used rapidly evolving mitochondrial genes to investigate connectivity patterns of three coral reef species targeted by fisheries in Fiji: Epinephelus merra (Serranidae), Halichoeres trimaculatus (Labridae), and Holothuria atra (Holothuriidae). The two fish species, E. merra and Ha. trimaculatus, exhibited low genetic structuring and high amounts of gene flow, whereas the sea cucumber Ho. atra displayed high genetic partitioning and predominantly westward gene flow. The idiosyncratic patterns observed among these species indicate that patterns of connectivity in Fiji are likely determined by a combination of oceanographic and ecological characteristics. Our data indicate that in the cases of species with high connectivity, other factors such as representation or political availability may dictate where reserves are placed. In low connectivity species, ensuring upstream and downstream connections is critical.

  16. Implementing system-wide risk stratification approaches: A review of critical success and failure factors.

    PubMed

    Huckel Schneider, Carmen; Gillespie, James A; Wilson, Andrew

    2017-05-01

    Risk stratification has become a widely used tool for linking people identified at risk of health deterioration to the most appropriate evidence-based care. This article systematically reviews recent literature to determine key factors that have been identified as critical enablers and/or barriers to successful implementation of risk stratification tools at a system level. A systematic search found 23 articles and four promising protocols for inclusion in the review, covering the use to 20 different risk stratification tools. These articles reported on only a small fraction of the risk stratification tools used in health systems; suggesting that while the development and statistical validation of risk stratification algorithms is widely reported, there has been little published evaluation of how they are implemented in real-world settings. Controlled studies provided some evidence that the use of risk stratification tools in combination with a care management plan offer patient benefits and that the use of a risk stratification tool to determine components of a care management plan may contribute to reductions in hospital readmissions, patient satisfaction and improved patient outcomes. Studies with the strongest focus on implementation used qualitative and case study methods. Among these, the literature converged on four key areas of implementation that were found to be critical for overcoming barriers to success: the engagement of clinicians and safeguarding equity, both of which address barriers of acceptance; the health system context to address administrative, political and system design barriers; and data management and integration to address logistical barriers.

  17. Advanced Glycation End-Products Induce Connective Tissue Growth Factor-Mediated Renal Fibrosis Predominantly through Transforming Growth Factor β-Independent Pathway

    PubMed Central

    Zhou, Guihua; Li, Cai; Cai, Lu

    2004-01-01

    Advanced glycation end-products (AGEs) play a critical role in diabetic nephropathy by stimulating extracellular matrix (ECM) synthesis. Connective tissue growth factor (CTGF) is a potent inducer of ECM synthesis and increases in the diabetic kidneys. To determine the critical role of CTGF in AGE-induced ECM accumulation leading to diabetic nephropathy, rats were given AGEs by intravenous injection for 6 weeks. AGE treatment induced a significant renal ECM accumulation, as shown by increases in periodic acid-Schiff-positive materials, fibronectin, and type IV collagen (Col IV) accumulation in glomeruli, and a mild renal dysfunction, as shown by increases in urinary volume and protein content. AGE treatment also caused significant increases in renal CTGF and transforming growth factor (TGF)-β1 mRNA and protein expression. Direct exposure of rat mesangial cells to AGEs in vitro significantly induced increases in fibronectin and Col IV production, which could be completely prevented by pretreatment with anti-CTGF antibody. AGE treatment also significantly increased both TGF-β1 and CTGF mRNA expression; however, inhibition of TGF-β1 mRNA expression by shRNA or neutralization of TGF-β1 protein by anti-TGF-β1 antibody did not significantly prevent AGE-increased expression of CTGF mRNA and protein. These results suggest that AGE-induced CTGF expression, predominantly through a TGF-β1-independent pathway, plays a critical role in renal ECM accumulation leading to diabetic nephropathy. PMID:15579446

  18. Can Mindfulness Training Improve Medication Adherence? Integrative Review of the Current Evidence and Proposed Conceptual Model.

    PubMed

    Salmoirago-Blotcher, Elena; Carey, Michael P

    Medication adherence is a complex, multi-determined behavior that is often influenced by system- (e.g., cost), drug- (e.g., regimen complexity), and patient-related (e.g., depression) factors. System-level approaches (e.g., making medications more affordable) are critically important but do not address patient-level factors that can undermine adherence. In this paper, we identify patient-level determinants of non-adherence and discuss whether mindfulness-training approaches that target these determinants can help to improve adherence to medical treatment. We highlight two chronic medical conditions (viz., heart failure and HIV) where poor adherence is a significant concern, and examine the evidence regarding the use of mindfulness interventions to improve medication adherence in these two conditions. We also discuss the theoretical underpinnings of mindfulness training with respect to medication adherence, and conclude by suggesting directions for future research. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Quantitative correlation between the void morphology of niobium-tin wires and their irreversible critical current degradation upon mechanical loading

    DOE PAGES

    Barth, Christian; Seeber, B.; Rack, A.; ...

    2018-04-26

    Understanding the critical current performance variation of Nb 3Sn superconducting wires under mechanical loading is a crucial issue for the design of next generation accelerator and fusion magnets. In these applications, the mechanical properties of the conductors may become a limiting factor due to the strong electro-magnetic forces resulting from the combination of large magnets and intense magnetic fields. In particular, the presence of voids in the superconducting filament structure, which are formed during the fabrication and the reaction heat treatment, determines localized stress concentrations and possibly the formation of cracks. In this work, we demonstrate a quantitative correlation betweenmore » the void morphology and the electro-mechanical limits measured on different Bronze route Nb 3Sn wires. Hot Isostatic Pressing (HIP) prior to the reaction heat treatment is utilized to partially eliminate the voids. The wires’ void distributions - with and without HIP treatment - are detected and statistically analyzed using high energy X-ray micro tomography. The stress concentration due to the shape and distribution of the voids as well as their impact on the electro-mechanical properties are determined through finite element method modeling. Lastly, the results are quantitatively correlated with the experimentally determined limits of the irreversible critical current degradation upon mechanical loading.« less

  20. Quantitative correlation between the void morphology of niobium-tin wires and their irreversible critical current degradation upon mechanical loading

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

    Barth, Christian; Seeber, B.; Rack, A.

    Understanding the critical current performance variation of Nb 3Sn superconducting wires under mechanical loading is a crucial issue for the design of next generation accelerator and fusion magnets. In these applications, the mechanical properties of the conductors may become a limiting factor due to the strong electro-magnetic forces resulting from the combination of large magnets and intense magnetic fields. In particular, the presence of voids in the superconducting filament structure, which are formed during the fabrication and the reaction heat treatment, determines localized stress concentrations and possibly the formation of cracks. In this work, we demonstrate a quantitative correlation betweenmore » the void morphology and the electro-mechanical limits measured on different Bronze route Nb 3Sn wires. Hot Isostatic Pressing (HIP) prior to the reaction heat treatment is utilized to partially eliminate the voids. The wires’ void distributions - with and without HIP treatment - are detected and statistically analyzed using high energy X-ray micro tomography. The stress concentration due to the shape and distribution of the voids as well as their impact on the electro-mechanical properties are determined through finite element method modeling. Lastly, the results are quantitatively correlated with the experimentally determined limits of the irreversible critical current degradation upon mechanical loading.« less

  1. C-Depth Method to Determine Diffusion Coefficient and Partition Coefficient of PCB in Building Materials.

    PubMed

    Liu, Cong; Kolarik, Barbara; Gunnarsen, Lars; Zhang, Yinping

    2015-10-20

    Polychlorinated biphenyls (PCBs) have been found to be persistent in the environment and possibly harmful. Many buildings are characterized with high PCB concentrations. Knowledge about partitioning between primary sources and building materials is critical for exposure assessment and practical remediation of PCB contamination. This study develops a C-depth method to determine diffusion coefficient (D) and partition coefficient (K), two key parameters governing the partitioning process. For concrete, a primary material studied here, relative standard deviations of results among five data sets are 5%-22% for K and 42-66% for D. Compared with existing methods, C-depth method overcomes the inability to obtain unique estimation for nonlinear regression and does not require assumed correlations for D and K among congeners. Comparison with a more sophisticated two-term approach implies significant uncertainty for D, and smaller uncertainty for K. However, considering uncertainties associated with sampling and chemical analysis, and impact of environmental factors, the results are acceptable for engineering applications. This was supported by good agreement between model prediction and measurement. Sensitivity analysis indicated that effective diffusion distance, contacting time of materials with primary sources, and depth of measured concentrations are critical for determining D, and PCB concentration in primary sources is critical for K.

  2. Quantitative correlation between the void morphology of niobium-tin wires and their irreversible critical current degradation upon mechanical loading.

    PubMed

    Barth, C; Seeber, B; Rack, A; Calzolaio, C; Zhai, Y; Matera, D; Senatore, C

    2018-04-26

    Understanding the critical current performance variation of Nb 3 Sn superconducting wires under mechanical loading is a crucial issue for the design of next generation accelerator and fusion magnets. In these applications, the mechanical properties of the conductors may become a limiting factor due to the strong electro-magnetic forces resulting from the combination of large magnets and intense magnetic fields. In particular, the presence of voids in the superconducting filament structure, which are formed during the fabrication and the reaction heat treatment, determines localized stress concentrations and possibly the formation of cracks. In this work, we demonstrate a quantitative correlation between the void morphology and the electro-mechanical limits measured on different Bronze route Nb 3 Sn wires. Hot Isostatic Pressing (HIP) prior to the reaction heat treatment is utilized to partially eliminate the voids. The wires' void distributions - with and without HIP treatment - are detected and statistically analyzed using high energy X-ray micro tomography. The stress concentration due to the shape and distribution of the voids as well as their impact on the electro-mechanical properties are determined through finite element method modeling. Finally, the results are quantitatively correlated with the experimentally determined limits of the irreversible critical current degradation upon mechanical loading.

  3. Part 1: Pressure ulcer assessment - the development of Critical Care Pressure Ulcer Assessment Tool made Easy (CALCULATE).

    PubMed

    Richardson, Annette; Barrow, Isabel

    2015-11-01

    Critically ill patients are at high risk of developing pressure ulcers resulting in serious untoward patient and health care system outcomes. Pressure ulcer prevention is therefore an important patient safety priority and establishing a structured approach to pressure ulcer risk assessment to identify patients at risk is a critical first step. The literature was searched using three electronic databases from 2000 to 2011 to identify papers reporting on pressure ulcer risk factors and assessment in adult critical care. The review and appraisal of papers were conducted by two critical care nurses. Papers underwent detailed review if they met inclusion criteria where they identified pressure ulcer assessment scores, scales or risk factors and related to adult critical care patients Seven papers were reviewed. No single assessment tool was sufficiently validated for critically ill patients and seven key critical care risk factors were identified. These risk factors were: mechanical ventilation, impaired circulation, dialysis, long surgery, low protein and too unstable to turn. The tool Critical Care Pressure Ulcer Assessment Tool made Easy (CALCULATE) was developed utilizing the risk factors from the literature and expert critical care nursing consensus decision-making. In the absence of current consensus, valid assessment scales and limited evidence for the most appropriate pressure ulcer assessment for critically ill patients, this assessment tool offers an easy, appropriate alternative for critically ill patients than existing tools primarily validated for acute care wards. 'CALCULATE' offers an important contribution towards the advancement and development of critical care pressure ulcer risk assessment. Future research is needed to further enhance and inform pressure ulcer risk assessment of the critically ill patients. The identification of critical care risk factors may be an indicative method of assessing pressure ulcer risk in the critically ill patients. © 2015 British Association of Critical Care Nurses.

  4. Plasma granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor levels in critical illness including sepsis and septic shock: relation to disease severity, multiple organ dysfunction, and mortality.

    PubMed

    Presneill, J J; Waring, P M; Layton, J E; Maher, D W; Cebon, J; Harley, N S; Wilson, J W; Cade, J F

    2000-07-01

    To define the circulating levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) during critical illness and to determine their relationship to the severity of illness as measured by the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the development of multiple organ dysfunction, or mortality. Prospective cohort study. University hospital intensive care unit. A total of 82 critically ill adult patients in four clinically defined groups, namely septic shock (n = 29), sepsis without shock (n = 17), shock without sepsis (n = 22), and nonseptic, nonshock controls (n = 14). None. During day 1 of septic shock, peak plasma levels of G-CSF, interleukin (IL)-6, and leukemia inhibitory factor (LIF), but not GM-CSF, were greater than in sepsis or shock alone (p < .001), and were correlated among themselves (rs = 0.44-0.77; p < .02) and with the APACHE II score (rs = 0.25-0.40; p = .03 to .18). G-CSF, IL-6, and UF, and sepsis, shock, septic shock, and APACHE II scores were strongly associated with organ dysfunction or 5-day mortality by univariate analysis. However, multiple logistic regression analysis showed that only septic shock remained significantly associated with organ dysfunction and only APACHE II scores and shock with 5-day mortality. Similarly, peak G-CSF, IL-6, and LIF were poorly predictive of 30-day mortality. Plasma levels of G-CSF, IL-6, and LIF are greatly elevated in critical illness, including septic shock, and are correlated with one another and with the severity of illness. However, they are not independently predictive of mortality, or the development of multiple organ dysfunction. GM-CSF was rarely elevated, suggesting different roles for G-CSF and GM-CSF in human septic shock.

  5. Development and psychometric properties of a questionnaire to assess barriers to feeding critically ill patients

    PubMed Central

    2013-01-01

    Background To successfully implement the recommendations of critical care nutrition guidelines, one potential approach is to identify barriers to providing optimal enteral nutrition (EN) in the intensive care unit (ICU), and then address these barriers systematically. Therefore, the purpose of this study was to develop a questionnaire to assess barriers to enterally feeding critically ill patients and to conduct preliminary validity testing of the new instrument. Methods The content of the questionnaire was guided by a published conceptual framework, literature review, and consultation with experts. The questionnaire was pre-tested on a convenience sample of 32 critical care practitioners, and then field tested with 186 critical care providers working at 5 hospitals in North America. The revised questionnaire was pilot tested at another ICU (n = 43). Finally, the questionnaire was distributed to a random sample of ICU nurses twice, two weeks apart, to determine test retest reliability (n = 17). Descriptive statistics, exploratory factor analysis, Cronbach alpha, intraclass correlations (ICC), and kappa coefficients were conducted to assess validity and reliability. Results We developed a questionnaire with 26 potential barriers to delivery of EN asking respondents to rate their importance as barriers in their ICU. Face and content validity of the questionnaire was established through literature review and expert input. The factor analysis indicated a five-factor solution and accounted for 72% of the variance in barriers: guideline recommendations and implementation strategies, delivery of EN to the patient, critical care provider attitudes and behavior, dietitian support, and ICU resources. Overall, the indices of internal reliability for the derived factor subscales and the overall instrument were acceptable (subscale Cronbach alphas range 0.84 – 0.89). However, the test retest reliability was variable and below acceptable thresholds for the majority of items (ICC’s range −0.13 to 0.70). The within group agreement, an indices reflecting the reliability of aggregating individual responses to the ICU level was also variable (ICC’s range 0.0 to 0.82). Conclusions We developed a questionnaire to identify barriers to enteral feeding in critically ill patients. Additional studies are planned to further revise and evaluate the reliability and validity of the instrument. PMID:24305039

  6. Social support satisfaction in adults with eating disorders: Does stance matter?

    PubMed

    Geller, Josie; Iyar, Megumi; Srikameswaran, Suja; Zelichowska, Joanna; Dunn, Erin C

    2017-07-01

    Although the role of social support is clearly established in the recovery of youth with eating disorders, little is known about factors that contribute to support satisfaction and improved treatment outcome in adults. This study examined the contribution of patient factors and perceived support stance used by family and friends in determining social support satisfaction. Individuals meeting DSM-IV criteria for an eating disorder (n = 182) completed measures of eating disorder and psychiatric severity, interpersonal functioning, perceived support stance used by family and friends, and social support satisfaction. Correlations indicated that both patient factors (lower psychiatric distress and fewer interpersonal difficulties) and perceived support stance (higher concerned and lower directive support) were associated with patient support satisfaction. Multiple regression analyses indicated that perceived support stance accounted for greater variance in social support satisfaction than did patient factors. Patient age was associated with differences in preferred support stance: expressions of caring were most critical for younger patients, whereas not being criticized or told what to do was most significant for older patients. This research suggests that the stance used when offering support is vital to the care of individuals with eating disorders. © 2017 Wiley Periodicals, Inc.

  7. Experimental determination of folding factor of benign breast cancer cell (MCF10A) and its effect on contact models and 3D manipulation of biological particles.

    PubMed

    Korayem, M H; Shahali, S; Rastegar, Z

    2018-06-01

    Plasma membrane of most cells is not smooth. The surfaces of both small and large micropermeable cells are folded and corrugated which makes mammalian cells to have a larger membrane surface than the supposed ideal mode, that is, the smooth sphere of the same volume. Since cancer is an anthropic disease, cancer cells tend to have a larger membrane area than normal cells. Therefore, cancer cells have higher folding factor and larger radius than normal and healthy cells. On the other hand, the prevalence of breast cancer has prompted researchers to improve the treatment options raised for the disease in the past. In this paper, the impact of folding factor of the cell surface has been investigated. Considering that AFM is one of the most effective tools in performing the tests at micro- and nanoscales, it was used to determine the topography of MCF10 cells and then the resulting images and results were used to experimentally extract the folding factor of cells. By applying this factor in the Hertz, DMT and JKR contact models in the elastic and viscoelastic states, these models have been modified and the simulation of the three models shows that the simulation results are closer to the experimental results by considering the folding in the calculations. Additionally, the simulation of 3D manipulation has been done in both elastic and viscoelastic states with and without consideration of folding. Finally, the results were compared to investigate the effects of folding of the cell surface to the critical force and critical time of sliding and rolling in contact with the substrate and AFM tip in the 3D manipulation model.

  8. Critical care in the surgical global period.

    PubMed

    Painter, Julie R

    2013-03-01

    This article explores the rules and regulations from Current Procedural Terminology (CPT) code set and US Medicare and Medicaid Services (Medicare) regarding multiple physicians reporting critical care services during the global period. The article takes into account the critical care definitions, regulations, documentation requirements, and services each provider can report to Medicare. A clinical scenario based on literature supporting the types of complications and care that might typically be included in the post-operative period for a patient who is surgically treated for a type A aortic dissection was analyzed. It was determined that multiple physicians may provide critical care services to a single patient during the global period. The physician who performed the primary procedure cannot report critical care separately unless documentation supporting use of modifier 25 (significant, separately identifiable services) or 24 (unrelated services) supports that critical care is unrelated to the global period. Other physicians may report critical care services separately if specific criteria are met. To report critical care services to Medicare, the patient's condition must meet the Medicare definition of critical care and the physicians should generally represent different specialties providing different aspects of care to the critically ill or injured patient as defined by Medicare. There should be no overlap in time of services provided by each physician. Each physician's documentation should clearly support medical necessity with the diagnosis demonstrating the critical nature of the patients' illness, the total time spent providing critical care, the critical care service provided, and other contributing factors.

  9. Using thermal units for estimating critical period of weed competition in off-season maize crop.

    PubMed

    López-Ovejero, Ramiro Fernando; y Garcia, Axel Garcia; de Carvalho, Saul Jorge P; Christoffoleti, Pedro J; Neto, Durval Dourado; Martins, Fernando; Nicolai, Marcelo

    2005-01-01

    Brazilian off-season maize production is characterized by low yield due to several factors, such as climate variability and inadequate management practices, specifically weed management. Thus, the goal of this study was to determinate the critical period of weed competition in off-season maize (Zea mays L.) crop using thermal units or growing degree days (GDD) approach to characterize crop growth and development. The study was carried out in experimental area of the University of São Paulo, Brazil, with weed control (C), as well as seven coexistence periods, 2, 4, 6, 8, and 12 leaves, flowering, and all crop cycle; fourteen treatments were done. Climate data were obtained from a weather station located close to the experimental area. To determine the critical period for weed control (CPWC) logistic models were fitted to yield data obtained in both W and C, as a function of GDD. For an arbitrary maximum yield loss fixed in 2.5%, the CPWC was found between 301 and 484 GDD (7-8 leaves). Also, when the arbitrary loss yield was fixed in 5 and 10%, the period before interference (PBI) was higher than the critical weed-free period (CWFP), suggesting that the weeds control can be done with only one application, between 144 and 410 GDD and 131 and 444 GDD (3-8 leaves), respectively. The GDD approach to characterize crop growth and development was successfully used to determine the critical period of weeds control in maize sown off-season. Further works will be necessary to better characterize the interaction and complexity of maize sown off-season with weeds. However, these results are encouraging because the possibility of the results to be extrapolated and because the potential of the method on providing important results to researchers, specifically crop modelers.

  10. Key factors for the implementation of successful, stand-alone village electrification schemes in Peru

    NASA Astrophysics Data System (ADS)

    Sanchez-Campos, Teodoro

    The hypothesis of this work is that there are social, financial, technical, managerial institutional and political key factors that may either support or prevent the success of small stand alone energy systems in rural areas. This research work aims at contributing to the identification of such factors and study their relevance to the performance and sustainability of stand alone energy systems in rural areas; to meet its purpose, a wide range of literature was reviewed including rural electrification programmes and projects, research and development projects on access to electricity in rural areas, impact studies and others, and a field research survey was done the Andes and Upper Jungle regions in Peru. Nineteen possible critical factors were identified, thirteen with relevance at the local context (the community or village), and six with relevance at the national (or wider) context. From literature review it was found that the possible local critical factors were relevant only to four categories of factors instead of the six considered initially (i.e. social, financial, technological and managerial): the other two categories, political and institutional were found to be more relevant to the national context, therefore those were included in the group of possible critical factors of wider context. A series of questionnaires were designed to collect field data information, which was later used to analyse and establish the relation of each identified factor with the success of the systems studied. The survey research was implemented in 14 villages, 7 with small diesel sets and 7 with small hydropower schemes, all spread in the Andes and Upper Jungle of Peru, which were carefully selected to be representative of regions with isolated stand alone systems and with different socioeconomic background. Out of the 13 possible critical factors of local context, it was found that only 3 are really critical, the others are important but not critical; one of them (technical assistance) was found to be closely linked to national capacity, therefore for practical reasons both are considered as one critical factor or wider context. Although more research study is needed to establish a more clearer result on the factors of wider context (national context), it was found that out of the 6 factors of wider context only one appears to be critical, the other 5 are important but not critical. Therefore the summary of critical factors is as follows: a) Critical Factors of Local Context o Management o Local capacity b) Critical Factors of National Context o Technical Support/national capacity On the local factors, management appears to be the most critical of all factors, because with good management, most of the other factors can be overcome. It was also found that "The small enterprise model" tested by Practical Action on small scale hydropower schemes is proving to be successful and other organisations are starting to use it in different contexts. Therefore future research is recommended on this particular management model in order to be useful for rural electrification programmes based on decentralised energy generation systems.

  11. Selected Aspects of Cryogenic Tank Fatigue Calculations for Offshore Application

    NASA Astrophysics Data System (ADS)

    Skrzypacz, J.; Jaszak, P.

    2018-02-01

    The paper presents the way of the fatigue life calculation of a cryogenic tank dedicated for the carriers ship application. The independent tank type C was taken into consideration. The calculation took into account a vast range of the load spectrum resulting in the ship accelerations. The stress at the most critical point of the tank was determined by means of the finite element method. The computation methods and codes used in the design of the LNG tank were presented. The number of fatigue cycles was determined by means of S-N curve. The cumulated linear damage theory was used to determine life factor.

  12. The NIH Cognitive and Emotional Health Project. Report of the Critical Evaluation Study Committee.

    PubMed

    Hendrie, Hugh C; Albert, Marilyn S; Butters, Meryl A; Gao, Sujuan; Knopman, David S; Launer, Lenore J; Yaffe, Kristine; Cuthbert, Bruce N; Edwards, Emmeline; Wagster, Molly V

    2006-01-01

    The Cognitive and Emotional Health Project (CEHP) seeks to identify the demographic, social, and biological determinants of cognitive and emotional health in the older adult. As part of the CEHP, a critical evaluation study committee was formed to assess the state of epidemiological research on demographic, social, and biological determinants of cognitive and emotional health. Criteria for inclusion in the survey were large cohort studies, longitudinal in design, participants predominantly 65 years or older, with measurements of both cognition and emotion, and information on a wide variety of demographic, psychosocial, and biological factors. North American and European studies, which met these criteria, were selected for the review. Outcome measures included cognition, cognitive decline, and cognitive function. For emotion, symptoms included depression and anxiety, positive and negative affect, subjective well being, mastery, and resilience. Ninety-six papers were identified that addressed cognitive and emotional outcomes. A large variety of risk factors were consistently identified with cognitive outcomes, particularly those previously associated with increased risk of cardiovascular disease. There was considerable overlap between risk factors for cognitive and emotional outcomes. This review identifies a large number of lifestyle and health behaviors that alter the risk for maintenance of cognitive and emotional health. Large longitudinal cohort studies are a unique source to explore factors associated with cognitive and emotional health. Secondary analyses of these studies should be encouraged as should the development of standardized questionnaires to measure cognitive and emotional health. Future research in this field should study cognitive and emotional health simultaneously.

  13. Extracting the pair distribution function of liquids and liquid-vapor surfaces by grazing incidence x-ray diffraction mode.

    PubMed

    Vaknin, David; Bu, Wei; Travesset, Alex

    2008-07-28

    We show that the structure factor S(q) of water can be obtained from x-ray synchrotron experiments at grazing angle of incidence (in reflection mode) by using a liquid surface diffractometer. The corrections used to obtain S(q) self-consistently are described. Applying these corrections to scans at different incident beam angles (above the critical angle) collapses the measured intensities into a single master curve, without fitting parameters, which within a scale factor yields S(q). Performing the measurements below the critical angle for total reflectivity yields the structure factor of the top most layers of the water/vapor interface. Our results indicate water restructuring at the vapor/water interface. We also introduce a new approach to extract g(r), the pair distribution function (PDF), by expressing the PDF as a linear sum of error functions whose parameters are refined by applying a nonlinear least square fit method. This approach enables a straightforward determination of the inherent uncertainties in the PDF. Implications of our results to previously measured and theoretical predictions of the PDF are also discussed.

  14. 21 CFR 113.100 - Processing and production records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... products, maximum fill-in or drained weight, or other critical factors specified in the scheduled process... end of the holding period; nature of container. (6) Food preservation methods wherein critical factors... scheduled processes used, including the thermal process, its associated critical factors, as well as other...

  15. 21 CFR 113.100 - Processing and production records.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... products, maximum fill-in or drained weight, or other critical factors specified in the scheduled process... end of the holding period; nature of container. (6) Food preservation methods wherein critical factors... scheduled processes used, including the thermal process, its associated critical factors, as well as other...

  16. 21 CFR 113.100 - Processing and production records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... products, maximum fill-in or drained weight, or other critical factors specified in the scheduled process... end of the holding period; nature of container. (6) Food preservation methods wherein critical factors... scheduled processes used, including the thermal process, its associated critical factors, as well as other...

  17. The critical domain size of stochastic population models.

    PubMed

    Reimer, Jody R; Bonsall, Michael B; Maini, Philip K

    2017-02-01

    Identifying the critical domain size necessary for a population to persist is an important question in ecology. Both demographic and environmental stochasticity impact a population's ability to persist. Here we explore ways of including this variability. We study populations with distinct dispersal and sedentary stages, which have traditionally been modelled using a deterministic integrodifference equation (IDE) framework. Individual-based models (IBMs) are the most intuitive stochastic analogues to IDEs but yield few analytic insights. We explore two alternate approaches; one is a scaling up to the population level using the Central Limit Theorem, and the other a variation on both Galton-Watson branching processes and branching processes in random environments. These branching process models closely approximate the IBM and yield insight into the factors determining the critical domain size for a given population subject to stochasticity.

  18. [Introduction of hazard analysis and critical control points (HACCP) principles at the flight catering food production plant].

    PubMed

    Popova, A Yu; Trukhina, G M; Mikailova, O M

    In the article there is considered the quality control and safety system implemented in the one of the largest flight catering food production plant for airline passengers and flying squad. The system for the control was based on the Hazard Analysis And Critical Control Points (HACCP) principles and developed hygienic and antiepidemic measures. There is considered the identification of hazard factors at stages of the technical process. There are presented results of the analysis data of monitoring for 6 critical control points over the five-year period. The quality control and safety system permit to decline food contamination risk during acceptance, preparation and supplying of in-flight meal. There was proved the efficiency of the implemented system. There are determined further ways of harmonization and implementation for HACCP principles in the plant.

  19. Structural factoring approach for analyzing stochastic networks

    NASA Technical Reports Server (NTRS)

    Hayhurst, Kelly J.; Shier, Douglas R.

    1991-01-01

    The problem of finding the distribution of the shortest path length through a stochastic network is investigated. A general algorithm for determining the exact distribution of the shortest path length is developed based on the concept of conditional factoring, in which a directed, stochastic network is decomposed into an equivalent set of smaller, generally less complex subnetworks. Several network constructs are identified and exploited to reduce significantly the computational effort required to solve a network problem relative to complete enumeration. This algorithm can be applied to two important classes of stochastic path problems: determining the critical path distribution for acyclic networks and the exact two-terminal reliability for probabilistic networks. Computational experience with the algorithm was encouraging and allowed the exact solution of networks that have been previously analyzed only by approximation techniques.

  20. Propylene glycol accumulation in critically ill patients receiving continuous intravenous lorazepam infusions.

    PubMed

    Horinek, Erica L; Kiser, Tyree H; Fish, Douglas N; MacLaren, Robert

    2009-12-01

    Lorazepam is recommended by the Society of Critical Care Medicine as the preferred agent for sedation of critically ill patients. Intravenous lorazepam contains propylene glycol, which has been associated with toxicity when high doses of lorazepam are administered. To evaluate the accumulation of propylene glycol in critically ill patients receiving lorazepam by continuous infusion and determine factors associated with propylene glycol concentration. A 6-month, retrospective, safety assessment was conducted of adults admitted to the medical intensive care unit who were receiving lorazepam by continuous infusion for 12 hours or more. Propylene glycol serum concentrations were obtained 24-48 hours after continuous-infusion lorazepam was initiated and every 3-5 days thereafter. Propylene glycol accumulation was defined as concentrations of 25 mg/dL or more. Groups with and without propylene glycol accumulation were compared and factors associated with propylene glycol concentration were determined using multivariate correlation regression analyses. Forty-eight propylene glycol serum samples were obtained from 33 patients. Fourteen (42%) patients had propylene glycol accumulation, representing 23 (48%) serum samples. Univariate analyses showed the following factors were related to propylene glycol accumulation: baseline renal dysfunction, presence of alcohol withdrawal, sex, age, Acute Physiology and Chronic Health Evaluation (APACHE II) score, rate of lorazepam continuous infusion, and 24-hour lorazepam dose. Multivariate linear regression modeling demonstrated that propylene glycol concentration was strongly associated with the continuous infusion rate and 24-hour dose (adjusted r(2) > or = 0.77; p < 0.001). Independent correlation analyses showed that these 2 variables were so strongly associated with propylene glycol concentration (r(2) > or = 0.71; p < 0.001) that they alone predicted propylene glycol concentration. Seven (21%) patients developed renal dysfunction after continuous-infusion lorazepam was initiated, but associated causes were indeterminable. Other possible propylene glycol-associated adverse effects were not observed. The continuous infusion rate and cumulative 24-hour lorazepam dose are strongly associated with and independently predict propylene glycol concentrations. Despite the absence of confirmed propylene glycol-associated adverse effects, clinicians should be aware that propylene glycol accumulation may occur with continuous-infusion lorazepam.

  1. How to Achieve Accurate Peer Assessment for High Value Written Assignments in a Senior Undergraduate Course

    ERIC Educational Resources Information Center

    Jeffery, Daniel; Yankulov, Krassimir; Crerar, Alison; Ritchie, Kerry

    2016-01-01

    The psychometric measures of accuracy, reliability and validity of peer assessment are critical qualities for its use as a supplement to instructor grading. In this study, we seek to determine which factors related to peer review are the most influential on these psychometric measures, with a primary focus on the accuracy of peer assessment or how…

  2. Diverse Protocols for Correlative Super-Resolution Fluorescence Imaging and Electron Microscopy of Cells and Tissue

    DTIC Science & Technology

    2016-05-25

    tissue is critical to biology. Many factors determine optimal experimental design, including attainable localization precision, ultrastructural...both imaging modalities. Examples include: weak tissue preservation protocols resulting in poor ultrastructure, e.g. mitochondrial cristae membranes...tension effects during sample drying that may result in artifacts44. Samples dried in the presence of polyvinyl alcohol do not have the haziness

  3. Morphological stability of sapphire crystallization front

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

    Baranov, V. V., E-mail: baranov.isc@gmail.com; Nizhankovskyi, S. V.

    2016-03-15

    The main factors and specificity of growth conditions for sapphire and Ti:sapphire crystals, which affect the morphological stability of the crystal–melt interface, have been investigated with allowance for the concentration and radiative melt supercooling. It is shown that the critical sapphire growth rate is determined to a great extent by the optical transparency of the melt and the mixing conditions near the crystallization front.

  4. Using technology to prevent adverse drug events in the intensive care unit.

    PubMed

    Hassan, Erkan; Badawi, Omar; Weber, Robert J; Cohen, Henry

    2010-06-01

    Critically ill patients are particularly susceptible to adverse drug events (ADEs) due to their rapidly changing and unstable physiology, complex therapeutic regimens, and large percentage of medications administered intravenously. There are a wide variety of technologies that can help prevent the points of failure commonly associated with ADEs (i.e., the five "Rights": right patient; right drug; right route; right dose; right frequency). These technologies are often categorized by their degree of complexity to design and engineer and the type of error they are designed to prevent. Focusing solely on the software and hardware design of technology may over- or underestimate the degree of difficulty to avoid ADEs at the bedside. Alternatively, we propose categorizing technological solutions by identifying the factors essential for success. The two major critical success factors are: 1) the degree of clinical assessment required by the clinician to appropriately evaluate and disposition the issue identified by a technology; and 2) the complexity associated with effective implementation. This classification provides a way of determining how ADE-preventing technologies in the intensive care unit can be successfully integrated into clinical practice. Although there are limited data on the effectiveness of many technologies in reducing ADEs, we will review the technologies currently available in the intensive care unit environment. We will also discuss critical success factors for implementation, common errors made during implementation, and the potential errors using these systems.

  5. The preanalytical optimization of blood cultures: a review and the clinical importance of benchmarking in 5 Belgian hospitals.

    PubMed

    Willems, Elise; Smismans, Annick; Cartuyvels, Reinoud; Coppens, Guy; Van Vaerenbergh, Kristien; Van den Abeele, Anne-Marie; Frans, Johan

    2012-05-01

    Bloodstream infections remain a major challenge in medicine. Optimal detection of pathogens is only possible if the quality of preanalytical factors is thoroughly controlled. Since the laboratory is responsible for this preanalytical phase, the quality control of critical factors should be integrated in its quality control program. The numerous recommendations regarding blood culture collection contain controversies. Only an unambiguous guideline permits standardization and interlaboratory quality control. We present an evidence-based concise guideline of critical preanalytical determinants for blood culture collection and summarize key performance indicators with their concomitant target values. In an attempt to benchmark, we compared the true-positive rate, contamination rate, and collected blood volume of blood culture bottles in 5 Belgian hospital laboratories. The true-positive blood culture rate fell within previously defined acceptation criteria by Baron et al. (2005) in all 5 hospitals, whereas the contamination rate exceeded the target value in 4 locations. Most unexpected, in each of the 5 laboratories, more than one third of the blood culture bottles were incorrectly filled, irrespective of the manufacturer of the blood culture vials. As a consequence of this shortcoming, one manufacturer recently developed an automatic blood volume monitoring system. In conclusion, clear recommendations for standardized blood culture collection combined with quality control of critical factors of the preanalytical phase are essential for diagnostic blood culture improvement. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Geometric and compositional factors on critical current density in YBa2Cu3O7‑δ films containing nanorods

    NASA Astrophysics Data System (ADS)

    Horide, Tomoya; Nagao, Sho; Izutsu, Ryosuke; Ishimaru, Manabu; Kita, Ryusuke; Matsumoto, Kaname

    2018-06-01

    Critical current density (J c) was investigated in YBa2Cu3O7‑δ films containing nanorods prepared with various nanorod materials, with variation of nanorod content, substrate temperature, and oxidization condition. Three types of compositional situation were realized: films containing strain induced oxygen vacancies; fully oxidized films containing cation compositional deviation; and oxygen deficient films. Normalized J c‑B behavior was determined via the matching field, which is a geometric factor, regardless of the compositional details. A J c‑critical temperature (T c) relation depending on distribution and fraction of compositional deviation (cation compositional deviation and strain induced oxygen vacancies) was found: the J c values decreased with decreasing T c due to the effect of T c on nanorod pinning strength in the fully oxidized films; J c decreased with decreasing oxygen pressure in the film cooling process after film deposition in spite of T c remaining almost the same, due to reduction of the effective area for current flow in the oxygen deficient films. Thus, a J c landscape based on geometric and compositional factors was obtained. The study highlights the importance of the J c‑T c analysis in the understanding of J c in YBa2Cu3O7‑δ films containing nanorods.

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

    Çataltepe, Ö. Aslan, E-mail: ozdenaslan@yahoo.com, E-mail: ozden.aslan@gedik.edu.tr; Özdemir, Z. Güven, E-mail: zguvenozdemir@yahoo.com; Onbaşlı, Ü., E-mail: phonon@doruk.net.tr

    In this work, the effect of oxygen doping on the critical parameters of the mercury based superconducting sample such as critical transition temperature, T{sub c}, critical magnetic field, H{sub c}, critical current density, J{sub c}, has been investigated by the magnetic susceptibility versus temperature (χ-T) and magnetization versus applied magnetic field (M-H) measurements and, X-Ray Diffraction (XRD) patterns. It has been observed that regardless of the oxygen doping concentration, the mercury cuprate system possesses two intrinsic superconducting phases together, HgBa{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8+x} and HgBa{sub 2}CaCu{sub 2}O{sub 6+x}. However, the highest T{sub c} has been determined for the optimummore » oxygen doped sample. Moreover, it has been revealed that superconducting properties, crystal lattice parameters, coherent lengths, ξ{sub ab}, ξ{sub c} and the anisotropy factor γ etc. are very sensitive to oxygen doping procedures. Hence, the results presented this work enables one to obtain the mercury based superconductor with the most desirable criticals and other parameters for theoretical and technological applications by arranging the oxygen doping concentration.« less

  8. Retention of bile salts in micellar electrokinetic chromatography: relation of capacity factor to octanol-water partition coefficient and critical micellar concentration.

    PubMed

    Lucangioli, S E; Carducci, C N; Tripodi, V P; Kenndler, E

    2001-12-25

    The capacity factors of 16 anionic cholates (from six bile salts, including their glyco- and tauro-conjugates) were determined in a micellar electrokinetic chromatography (MEKC) system consisting of buffer, pH 7.5 (phosphate-boric acid; 20 mmol/l) with 50 mmol/l sodium dodecyl sulfate (SDS) as micelle former and 10% acetonitrile as organic modifier. The capacity factors of the fully dissociated, negatively charged analytes (ranging between 0.2 and 60) were calculated from their mobilities, with a reference background electrolyte (BGE) without SDS representing "free" solution. For comparison, the capacity factors were derived for a second reference BGE where the SDS concentration (5 mmol/l) is close to the critical micellar concentration (CMC). The capacity factors are compared with the logarithm of the octanol-water partition coefficient, log Pow, as measure for lipophilicity. Clear disagreement between these two parameters is found especially for epimeric cholates with the hydroxy group in position 7. In contrast, fair relation between the capacity factor of the analytes and their CMC is observed both depending strongly on the orientation of the OH groups, and tauro-conjugation as well. In this respect the retention behaviour of the bile salts in MEKC seems to reflect their role as detergents in living systems, and might serve as model parameter beyond lipophilicity.

  9. Most important needs of family members of critical patients in light of the critical care family needs inventory.

    PubMed

    Padilla Fortunatti, Cristóbal Felipe

    2014-01-01

    This work sought to identify the most important needs for family members of adult critical patients as described in the literature pursuant to the dimensions established in the "Critical Care Family Needs Inventory" (CCFNI) by Molter and Leske. A literature review was carried out by using the CCFNI instrument. The databases used were: Pubmed, CINAHL, Proquest Nursing & Allied Health Source, Proquest Psychology Journals, LILACS, Science Direct, Ovid SP, PsyicINFO, and SciELO. The following limitations for the search were identified: adult patients, articles in English and Spanish, with abstract and complete text available and which had been published from 2003 to June 2013; 15 articles were included. The family's hope on desired results and sincere communication with the healthcare staff turned out to be the most relevant needs, while the least important were related to comfort and having support structures or systems. Most of the studies were conducted in Asia and North America revealing differences in the order of importance assigned to each necessity. Certain sociodemographic and cultural characteristics impact upon how family members rank their needs; this also occurs with the nature of the most important needs for the family and the factors determining their prioritization. The articles included in this review mention the frequent interaction with the family and their holistic view of the person beyond the illness, determine that nurses are the most appropriate professionals to know and satisfy the family needs of critical patients.

  10. Critical role of tumor necrosis factor receptor 1 in the pathogenesis of pulmonary emphysema in mice.

    PubMed

    Fujita, Masaki; Ouchi, Hiroshi; Ikegame, Satoshi; Harada, Eiji; Matsumoto, Takemasa; Uchino, Junji; Nakanishi, Yoichi; Watanabe, Kentaro

    2016-01-01

    COPD is a major cause of chronic morbidity and mortality throughout the world. Although tumor necrosis factor-α (TNF-α) has a critical role in the development of COPD, the role of different TNF receptors (TNFRs) in pulmonary emphysema has not been resolved. We aimed to clarify the role of TNFRs in the development of pulmonary emphysema. TNF-α transgenic mice, a murine model of COPD in which the mice spontaneously develop emphysema with a large increase in lung volume and pulmonary hypertension, were crossed with either TNFR1-deficient mice or TNFR2-deficient mice. After 6 months, the gross appearance of the lung, lung histology, and pulmonary and cardiac physiology were determined. In addition, the relationship between apoptosis and emphysema was investigated. Pulmonary emphysema-like changes disappeared with deletion of TNFR1. However, slight improvements were attained with deletion of TNFR2. Apoptotic cells in the interstitium of the lung were observed in TNF-α transgenic mice. The apoptotic signals through TNFR1 appear critical for the pathogenesis of pulmonary emphysema. In contrast, the inflammatory process has a less important role for the development of emphysema.

  11. Latent variable modeling to analyze the effects of process parameters on the dissolution of paracetamol tablet

    PubMed Central

    Sun, Fei; Xu, Bing; Zhang, Yi; Dai, Shengyun; Shi, Xinyuan; Qiao, Yanjiang

    2017-01-01

    ABSTRACT The dissolution is one of the critical quality attributes (CQAs) of oral solid dosage forms because it relates to the absorption of drug. In this paper, the influence of raw materials, granules and process parameters on the dissolution of paracetamol tablet was analyzed using latent variable modeling methods. The variability in raw materials and granules was understood based on the principle component analysis (PCA), respectively. A multi-block partial least squares (MBPLS) model was used to determine the critical factors affecting the dissolution. The results showed that the binder amount, the post granulation time, the API content in granule, the fill depth and the punch tip separation distance were the critical factors with variable importance in the projection (VIP) values larger than 1. The importance of each unit of the whole process was also ranked using the block importance in the projection (BIP) index. It was concluded that latent variable models (LVMs) were very useful tools to extract information from the available data and improve the understanding on dissolution behavior of paracetamol tablet. The obtained LVMs were also helpful to propose the process design space and to design control strategies in the further research. PMID:27689242

  12. Gender related Long-term Differences after Open Infrainguinal Surgery for Critical Limb Ischemia.

    PubMed

    Lejay, A; Schaeffer, M; Georg, Y; Lucereau, B; Roussin, M; Girsowicz, E; Delay, C; Schwein, A; Thaveau, F; Geny, B; Chakfe, N

    2015-10-01

    The role of gender on long-term infrainguinal open surgery outcomes still remains uncertain in critical limb ischemia patients. The aim of this study is to evaluate the gender-specific differences in patient characteristics and long-term clinical outcomes in terms of survival, primary patency and limb salvage among patients undergoing infrainguinal open surgery for CLI. All consecutive patients undergoing infrainguinal open surgery for critical limb ischemia between 2003 and 2012 were included. Survival, limb salvage and primary patency rates were assessed. Independent outcome determinants were identified by the Cox proportional hazard ratio using age and gender as adjustment factors. 584 patients (269 women and 315 men, mean age 76 and 71 years respectively) underwent 658 infrainguinal open surgery (313 in women and 345 in men). Survival rate at 6 years was lower among women compared to men with 53.5% vs 70.9% (p < 0.001). The same applied to primary patency (35.9% vs 52.4%, p < 0.001) and limb salvage (54.3% vs 81.1%, p < 0.001) at 6 years. Female-gender was an independent factor predicting death (hazard ratio 1.50), thrombosis (hazard ratio 2.37) and limb loss (hazard ratio 7.05) in age and gender-adjusted analysis. Gender-related disparity in critical limb ischemia open surgical revascularization outcomes still remains. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  13. [Karl Marx and the Malthusian theory of population].

    PubMed

    Jaggi, S

    1985-06-01

    An analysis of the works of Karl Marx is presented in order to demonstrate the importance of the population factor. The author contends that population growth is a critical factor in Marx's theory of the progressive impoverishment of the working class. However, because of his reluctance to acknowledge the value of the Malthusian contribution, Marx focused his analysis of the labor force under capitalism on the demand for workers and neglected the supply side, which is determined by the growth of population. The author concludes that Marxist theory would have benefited from greater consideration of Malthusian theory.

  14. ZEB1 drives epithelial-to-mesenchymal transition in lung cancer. | Office of Cancer Genomics

    Cancer.gov

    Increased expression of zinc finger E-box binding homeobox 1 (ZEB1) is associated with tumor grade and metastasis in lung cancer, likely due to its role as a transcription factor in epithelial-to-mesenchymal transition (EMT). Here, we modeled malignant transformation in human bronchial epithelial cells (HBECs) and determined that EMT and ZEB1 expression are early, critical events in lung cancer pathogenesis. Specific oncogenic mutations in TP53 and KRAS were required for HBECs to engage EMT machinery in response to microenvironmental (serum/TGF-β) or oncogenetic (MYC) factors.

  15. Tumor Endothelial Cells

    PubMed Central

    Dudley, Andrew C.

    2012-01-01

    The vascular endothelium is a dynamic cellular “organ” that controls passage of nutrients into tissues, maintains the flow of blood, and regulates the trafficking of leukocytes. In tumors, factors such as hypoxia and chronic growth factor stimulation result in endothelial dysfunction. For example, tumor blood vessels have irregular diameters; they are fragile, leaky, and blood flow is abnormal. There is now good evidence that these abnormalities in the tumor endothelium contribute to tumor growth and metastasis. Thus, determining the biological basis underlying these abnormalities is critical for understanding the pathophysiology of tumor progression and facilitating the design and delivery of effective antiangiogenic therapies. PMID:22393533

  16. Risk factors & screening modalities for oral cancer.

    PubMed

    Chau, Steven

    2008-01-01

    Dentists are at the forefront for screening oral cancer. In addition to the well known carcinogenic potential of tobacco and alcohol, betel nut chewing and human papilloma virus are important risk factors in the development of oral cancer. To aid in screening and decreasing morbidity and mortality from oral cancer, a variety of techniques have been developed. These techniques show promise but they require additional investigations to determine their usefulness in oral cancer detection. Dentists need to be well educated and vigilant when dealing with all patients they encounter. Early detection, diagnosis and treatment are critical for the effective management of oral cancers.

  17. A Synthesis and Survey of Critical Success Factors for Computer Technology Projects

    ERIC Educational Resources Information Center

    Baker, Ross A.

    2012-01-01

    The author investigated the existence of critical success factors for computer technology projects. Current research literature and a survey of experienced project managers indicate that there are 23 critical success factors (CSFs) that correlate with project success. The survey gathered an assessment of project success and the degree to which…

  18. Documentation Status as a Contextual Determinant of HIV Risk Among Young Transgender Latinas.

    PubMed

    Palazzolo, Sarah L; Yamanis, Thespina J; De Jesus, Maria; Maguire-Marshall, Molly; Barker, Suyanna L

    2016-04-01

    The purpose of this study was to explore the contextual factors that determine or mitigate vulnerability to HIV among Latina transgender women. Documentation status (legal authorization to live in the United States) has been cited by other studies as a barrier to recruitment or engagement in HIV-related care among immigrant Latinos, but not explored as a determinant of HIV risk for transgender immigrant Latinas. We collaborated with a community-based organization to explore these contextual, including social and structural, factors. In-depth interviews in Spanish captured life histories of eight 18- to 29-year-old transgender Latinas, who collectively self-identify as chicas trans. Codes were assigned deductively from the interview guide, and emerging themes were identified throughout data collection. Most participants migrated to the United States from Central America after experiencing discrimination and violence in their countries of origin. Participants emphasized documentation status as a critical factor in three areas related to social and structural determinants of HIV risk: gender identity expression, access to services, and relationship power dynamics. Chicas trans who gained legal asylum reported greater control over sexual relationships, improved access to services, and less risky employment. Documentation status emerged as a key HIV risk factor for this population. For undocumented transgender Latinas, legal asylum appears to be a promising HIV-related protective factor. Further research could assess whether legal assistance combined with wraparound support services affects HIV prevention for this population.

  19. Documentation Status as a Contextual Determinant of HIV Risk Among Young Transgender Latinas

    PubMed Central

    Palazzolo, Sarah L.; De Jesus, Maria; Maguire-Marshall, Molly; Barker, Suyanna L.

    2016-01-01

    Abstract Purpose: The purpose of this study was to explore the contextual factors that determine or mitigate vulnerability to HIV among Latina transgender women. Documentation status (legal authorization to live in the United States) has been cited by other studies as a barrier to recruitment or engagement in HIV-related care among immigrant Latinos, but not explored as a determinant of HIV risk for transgender immigrant Latinas. Methods: We collaborated with a community-based organization to explore these contextual, including social and structural, factors. In-depth interviews in Spanish captured life histories of eight 18- to 29-year-old transgender Latinas, who collectively self-identify as chicas trans. Codes were assigned deductively from the interview guide, and emerging themes were identified throughout data collection. Results: Most participants migrated to the United States from Central America after experiencing discrimination and violence in their countries of origin. Participants emphasized documentation status as a critical factor in three areas related to social and structural determinants of HIV risk: gender identity expression, access to services, and relationship power dynamics. Chicas trans who gained legal asylum reported greater control over sexual relationships, improved access to services, and less risky employment. Conclusions: Documentation status emerged as a key HIV risk factor for this population. For undocumented transgender Latinas, legal asylum appears to be a promising HIV-related protective factor. Further research could assess whether legal assistance combined with wraparound support services affects HIV prevention for this population. PMID:26669583

  20. Critical factors in the establishment of allopolyploids.

    PubMed

    Fowler, Norma L; Levin, Donald A

    2016-07-01

    The growth and spread of new polyploid populations have been explained in terms of fitness advantages over their diploid progenitors. However, a fitness advantage is not sufficient to insure the establishment of a polyploid; it must also overcome the obstacles of demographic stochasticity and minority disadvantage. Several studies have addressed the population dynamics of autopolyploids, but the present study is the first to consider allopolyploids, which are affected by more factors than autopolyploids. We constructed a population dynamic model of four types of plants (two parent species, hybrids, allopolyploids) that also included an explicit breeding system. The numbers of plants of each type were the most important factors determining whether the new allopolyploid would become established. More polyploid plants greatly increased the likelihood of polyploid persistence. More plants of the parent species and more hybrids resulted in more polyploids being produced. The model parameters with the most effect on polyploid establishment were potential population size (K), individual plant fecundity, and niche separation (α). The most important breeding system parameters were selfing rates, which mitigated minority disadvantage imposed by pollen limitation. The importance of population sizes, and the parameters that controlled them, in overcoming demographic stochasticity parallels the well-recognized role of propagule pressure in determining the success of invasive species. We modeled the establishment of a new allopolyploid; analogous considerations would affect the establishment of a new autopolyploid. The critical role of population sizes in polyploid establishment should be more widely recognized. © 2016 Botanical Society of America.

  1. Critical Concentration Ratio for Solar Thermoelectric Generators

    NASA Astrophysics Data System (ADS)

    ur Rehman, Naveed; Siddiqui, Mubashir Ali

    2016-10-01

    A correlation for determining the critical concentration ratio (CCR) of solar concentrated thermoelectric generators (SCTEGs) has been established, and the significance of the contributing parameters is discussed in detail. For any SCTEG, higher concentration ratio leads to higher temperatures at the hot side of modules. However, the maximum value of this temperature for safe operation is limited by the material properties of the modules and should be considered as an important design constraint. Taking into account this limitation, the CCR can be defined as the maximum concentration ratio usable for a particular SCTEG. The established correlation is based on factors associated with the material and geometric properties of modules, thermal characteristics of the receiver, installation site attributes, and thermal and electrical operating conditions. To reduce the number of terms in the correlation, these factors are combined to form dimensionless groups by applying the Buckingham Pi theorem. A correlation model containing these groups is proposed and fit to a dataset obtained by simulating a thermodynamic (physical) model over sampled values acquired by applying the Latin hypercube sampling (LHS) technique over a realistic distribution of factors. The coefficient of determination and relative error are found to be 97% and ±20%, respectively. The correlation is validated by comparing the predicted results with literature values. In addition, the significance and effects of the Pi groups on the CCR are evaluated and thoroughly discussed. This study will lead to a wide range of opportunities regarding design and optimization of SCTEGs.

  2. Assessment of Diarrheal Disease Prevalence and Associated Risk Factors in Children of 6-59 Months Old at Adama District Rural Kebeles, Eastern Ethiopia, January/2015.

    PubMed

    Regassa, Wakigari; Lemma, Seblewengel

    2016-11-01

    Diarrheal disease is the commonchildhood illness and a leading killer of children aged under 5 years, especially in developing countries like Ethiopia. The aim of this study was to assess the prevalence of diarrheal disease and associated risk factors among children of 6-59 months old at Adama district rural kebeles, Eastern Ethiopia. Community based cross sectional study design was conducted in January/2015. Descriptive method was used to describe study variables quantitatively and explanatory method to identify the effect of determinant factors on diarrheal disease occurrence. A single population proportion sample size formula was applied. Random sampling procedure was used by lottery method to select five kebeles and 442 house-holds. Data was collected by using pretested, structured questionnaires through interview and observational checklist by trained data collectors. Double entry was made to epi-info 3.5.3 and & transferred to SPSS20 for analysis. The two weeks' period prevalence of diarrheal disease in children aged 6 to59 months was 14.7%; 95%CI [11.5-18.1]. mother/caregiver who did not practice hand washing during the critical time was the only factor identified to be significantly associated with AOR=2.2; 95%CI [1.0-4.7] for the child hood diarrheal disease occurrence at Adama distict rural kebeles. Diarrheal disease prevalence is changed by child's caregiver hand washing practice during critical time. Health education for child's caregiver on hand washing practice during critical time is an important intervention for the prevention of diarrheal disease prevalence among children.

  3. Genetic mouse models of brain ageing and Alzheimer's disease.

    PubMed

    Bilkei-Gorzo, Andras

    2014-05-01

    Progression of brain ageing is influenced by a complex interaction of genetic and environmental factors. Analysis of genetically modified animals with uniform genetic backgrounds in a standardised, controlled environment enables the dissection of critical determinants of brain ageing on a molecular level. Human and animal studies suggest that increased load of damaged macromolecules, efficacy of DNA maintenance, mitochondrial activity, and cellular stress defences are critical determinants of brain ageing. Surprisingly, mouse lines with genetic impairment of anti-oxidative capacity generally did not show enhanced cognitive ageing but rather an increased sensitivity to oxidative challenge. Mouse lines with impaired mitochondrial activity had critically short life spans or severe and rapidly progressing neurodegeneration. Strains with impaired clearance in damaged macromolecules or defects in the regulation of cellular stress defences showed alterations in the onset and progression of cognitive decline. Importantly, reduced insulin/insulin-like growth factor signalling generally increased life span but impaired cognitive functions revealing a complex interaction between ageing of the brain and of the body. Brain ageing is accompanied by an increased risk of developing Alzheimer's disease. Transgenic mouse models expressing high levels of mutant human amyloid precursor protein showed a number of symptoms and pathophysiological processes typical for early phase of Alzheimer's disease. Generally, therapeutic strategies effective against Alzheimer's disease in humans were also active in the Tg2576, APP23, APP/PS1 and 5xFAD lines, but a large number of false positive findings were also reported. The 3xtg AD model likely has the highest face and construct validity but further studies are needed. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Effective planning and management as critical factors in urban water supply and management in Umuahia and Aba, Abia State, Nigeria

    NASA Astrophysics Data System (ADS)

    Uchegbu, Smart N.

    Plan and policy development usually define the course, goal, execution, success or failure of any public utilities initiative. Urban water supply is not an exception. Planning and management in public water supply systems often determine the quality of service the water supply authorities can render. This paper, therefore, addresses the issue of effective planning and management as critical determinants of urban water supply and management with respect to two Nigerian cities Umuahia and Aba both in Abia State. Appropriate sampling methods systematic sampling and cluster techniques were employed in order to collect data for the study. The collected data were analyzed using multiple linear regression. The findings of the study indicate that planning and management indices such as funding, manpower, water storage tank capacity greatly influence the volume of water supplied in the study areas. Funding was identified as a major determinant of the efficiency of the water supply system. Therefore, the study advocates the need for sector reforms that would usher in private participants in the water sector both for improved funding and enhanced productivity.

  5. Astronaut Exposures to Ionizing Radiation in a Lightly-Shielded Spacesuit

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Simonsen, L. C.; Shinn, J. L.; Kim, M.-H. Y.; Cucinotta, F. A.; Badavi, F. F.; Atwell, W.

    1999-01-01

    The normal working and living areas of the astronauts are designed to provide an acceptable level of protection against the hazards of ionizing radiation of the space environment. Still there are occasions when they must don a spacesuit designed mainly for environmental control and mobility and leave the confines of their better-protected domain. This is especially true for deep space exploration. The impact of spacesuit construction on the exposure of critical astronaut organs will be examined in the ionizing radiation environments of free space, the lunar surface and the Martian surface. The computerized anatomical male model is used to evaluate astronaut self-shielding factors and to determine space radiation exposures to critical radiosensitive human organs.

  6. Corrosion products of carbonation induced corrosion in existing reinforced concrete facades

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

    Köliö, Arto; Honkanen, Mari; Lahdensivu, Jukka

    Active corrosion in reinforced concrete structures is controlled by environmental conditions and material properties. These factors determine the corrosion rate and type of corrosion products which govern the total achieved service life. The type and critical amount of corrosion products were studied by electron microscopy and X-ray diffractometry on concrete and reinforcement samples from existing concrete facades on visually damaged locations. The corrosion products in outdoor environment exposed concrete facades are mostly hydroxides (Feroxyhite, Goethite and Lepidocrocite) with a volume ratio to Fe of approximately 3. The results can be used to calibrate calculation of the critical corrosion penetration ofmore » concrete facade panels.« less

  7. Dose determinants in continuous renal replacement therapy.

    PubMed

    Clark, William R; Turk, Joseph E; Kraus, Michael A; Gao, Dayong

    2003-09-01

    Increasing attention is being paid to quantifying the dose of dialysis prescribed and delivered to critically ill patients with acute renal failure (ARF). Recent trials in both the intermittent hemodialysis (IHD) and continuous renal replacement therapy (CRRT) realms have suggested that a direct relationship between dose and survival exists for both of these therapies. The purpose of this review, first, is to analyze critically the above-mentioned dose/outcome studies in acute dialysis. Subsequently, the factors influencing dose prescription and delivery are discussed, with the focus on continuous venovenous hemofiltration (CVVH). Specifically, differences between postdilution and predilution CVVH will be highlighted, and the importance of blood flow rate in dose delivery for these therapies will be discussed.

  8. Patterns of Positive Selection of the Myogenic Regulatory Factor Gene Family in Vertebrates

    PubMed Central

    Zhao, Xiao; Yu, Qi; Huang, Ling; Liu, Qing-Xin

    2014-01-01

    The functional divergence of transcriptional factors is critical in the evolution of transcriptional regulation. However, the mechanism of functional divergence among these factors remains unclear. Here, we performed an evolutionary analysis for positive selection in members of the myogenic regulatory factor (MRF) gene family of vertebrates. We selected 153 complete vertebrate MRF nucleotide sequences from our analyses, which revealed substantial evidence of positive selection. Here, we show that sites under positive selection were more frequently detected and identified from the genes encoding the myogenic differentiation factors (MyoG and Myf6) than the genes encoding myogenic determination factors (Myf5 and MyoD). Additionally, the functional divergence within the myogenic determination factors or differentiation factors was also under positive selection pressure. The positive selection sites were more frequently detected from MyoG and MyoD than Myf6 and Myf5, respectively. Amino acid residues under positive selection were identified mainly in their transcription activation domains and on the surface of protein three-dimensional structures. These data suggest that the functional gain and divergence of myogenic regulatory factors were driven by distinct positive selection of their transcription activation domains, whereas the function of the DNA binding domains was conserved in evolution. Our study evaluated the mechanism of functional divergence of the transcriptional regulation factors within a family, whereby the functions of their transcription activation domains diverged under positive selection during evolution. PMID:24651579

  9. The role of critical thinking skills and learning styles of university students in their academic performance.

    PubMed

    Ghazivakili, Zohre; Norouzi Nia, Roohangiz; Panahi, Faride; Karimi, Mehrdad; Gholsorkhi, Hayede; Ahmadi, Zarrin

    2014-07-01

    The Current world needs people who have a lot of different abilities such as cognition and application of different ways of thinking, research, problem solving, critical thinking skills and creativity. In addition to critical thinking, learning styles is another key factor which has an essential role in the process of problem solving. This study aimed to determine the relationship between learning styles and critical thinking of students and their academic performance in Alborz University of Medical Science. This cross-correlation study was performed in 2012, on 216 students of Alborz University who were selected randomly by the stratified random sampling. The data was obtained via a three-part questionnaire included demographic data, Kolb standardized questionnaire of learning style and California critical thinking standardized questionnaire. The academic performance of the students was extracted by the school records. The validity of the instruments was determined in terms of content validity, and the reliability was gained through internal consistency methods. Cronbach's alpha coefficient was found to be 0.78 for the California critical thinking questionnaire. The Chi Square test, Independent t-test, one way ANOVA and Pearson correlation test were used to determine relationship between variables. The Package SPSS14 statistical software was used to analyze data with a significant level of p<0.05. Our findings indicated the significant difference of mean score in four learning style, suggesting university students with convergent learning style have better performance than other groups. Also learning style had a relationship with age, gender, field of study, semester and job. The results about the critical thinking of the students showed that the mean of deductive reasoning and evaluation skills were higher than that of other skills and analytical skills had the lowest mean and there was a positive significant relationship between the students' performance with inferential skill and the total score of critical thinking skills (p<0.05). Furthermore, evaluation skills and deductive reasoning had significant relationship. On the other hand, the mean total score of critical thinking had significant difference between different learning styles. The results of this study showed that the learning styles, critical thinking and academic performance are significantly associated with one another. Considering the growing importance of critical thinking in enhancing the professional competence of individuals, it's recommended to use teaching methods consistent with the learning style because it would be more effective in this context.

  10. The role of critical thinking skills and learning styles of university students in their academic performance

    PubMed Central

    GHAZIVAKILI, ZOHRE; NOROUZI NIA, ROOHANGIZ; PANAHI, FARIDE; KARIMI, MEHRDAD; GHOLSORKHI, HAYEDE; AHMADI, ZARRIN

    2014-01-01

    Introduction: The Current world needs people who have a lot of different abilities such as cognition and application of different ways of thinking, research, problem solving, critical thinking skills and creativity. In addition to critical thinking, learning styles is another key factor which has an essential role in the process of problem solving. This study aimed to determine the relationship between learning styles and critical thinking of students and their academic performance in Alborz University of Medical Science. Methods: This cross-correlation study was performed in 2012, on 216 students of Alborz University who were selected randomly by the stratified random sampling. The data was obtained via a three-part questionnaire included demographic data, Kolb standardized questionnaire of learning style and California critical thinking standardized questionnaire. The academic performance of the students was extracted by the school records. The validity of the instruments was determined in terms of content validity, and the reliability was gained through internal consistency methods. Cronbach's alpha coefficient was found to be 0.78 for the California critical thinking questionnaire. The Chi Square test, Independent t-test, one way ANOVA and Pearson correlation test were used to determine relationship between variables. The Package SPSS14 statistical software was used to analyze data with a significant level of p<0.05. Results: Our findings indicated the significant difference of mean score in four learning style, suggesting university students with convergent learning style have better performance than other groups. Also learning style had a relationship with age, gender, field of study, semester and job. The results about the critical thinking of the students showed that the mean of deductive reasoning and evaluation skills were higher than that of other skills and analytical skills had the lowest mean and there was a positive significant relationship between the students’ performance with inferential skill and the total score of critical thinking skills (p<0.05). Furthermore, evaluation skills and deductive reasoning had significant relationship. On the other hand, the mean total score of critical thinking had significant difference between different learning styles. Conclusion: The results of this study showed that the learning styles, critical thinking and academic performance are significantly associated with one another. Considering the growing importance of critical thinking in enhancing the professional competence of individuals, it's recommended to use teaching methods consistent with the learning style because it would be more effective in this context. PMID:25512928

  11. Assessing Terrorist Motivations for Attacking Critical Infrastructure

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

    Ackerman, G; Abhayaratne, P; Bale, J

    Certain types of infrastructure--critical infrastructure (CI)--play vital roles in underpinning our economy, security and way of life. These complex and often interconnected systems have become so ubiquitous and essential to day-to-day life that they are easily taken for granted. Often it is only when the important services provided by such infrastructure are interrupted--when we lose easy access to electricity, health care, telecommunications, transportation or water, for example--that we are conscious of our great dependence on these networks and of the vulnerabilities that stem from such dependence. Unfortunately, it must be assumed that many terrorists are all too aware that CImore » facilities pose high-value targets that, if successfully attacked, have the potential to dramatically disrupt the normal rhythm of society, cause public fear and intimidation, and generate significant publicity. Indeed, revelations emerging at the time of this writing about Al Qaida's efforts to prepare for possible attacks on major financial facilities in New York, New Jersey, and the District of Columbia remind us just how real and immediate such threats to CI may be. Simply being aware that our nation's critical infrastructure presents terrorists with a plethora of targets, however, does little to mitigate the dangers of CI attacks. In order to prevent and preempt such terrorist acts, better understanding of the threats and vulnerabilities relating to critical infrastructure is required. The Center for Nonproliferation Studies (CNS) presents this document as both a contribution to the understanding of such threats and an initial effort at ''operationalizing'' its findings for use by analysts who work on issues of critical infrastructure protection. Specifically, this study focuses on a subsidiary aspect of CI threat assessment that has thus far remained largely unaddressed by contemporary terrorism research: the motivations and related factors that determine whether a terrorist organization will attack critical infrastructure. In other words, this research investigates: (1) why terrorists choose to attack critical infrastructure rather than other targets; (2) how groups make such decisions; (3) what, if any, types of groups are most inclined to attack critical infrastructure targets; and (4) which types of critical infrastructure terrorists prefer to attack and why. In an effort to address the above questions as comprehensively as possible, the project team employed four discrete investigative approaches in its research design. These include: (1) a review of existing terrorism and threat assessment literature to glean expert consensus regarding terrorist target selection, as well as to identify theoretical approaches that might be valuable to analysts and decision-makers who are seeking to understand such terrorist group decision-making processes; (2) the preparation of several concise case studies to help identify internal group factors and contextual influences that have played significant roles in leading some terrorist groups to attack critical infrastructure; (3) the creation of a new database--the Critical Infrastructure Terrorist Incident Catalog (CrITC)--to capture a large sample of empirical CI attack data that might be used to illuminate the nature of such attacks to date; and (4) the development of a new analytical framework--the Determinants Effecting Critical Infrastructure Decisions (DECIDe) Framework--designed to make the factors and dynamics identified by the study more ''usable'' in any future efforts to assess terrorist intentions to target critical infrastructure. Although each is addressed separately in the following chapters, none of the four aspects of this study were developed in isolation. Rather, all the constituent elements of the project informed--and were informed by--the others. For example, the review of the available literature on terrorist target selection made possible the identification of several target selection factors that were both important in the development of the analytical framework and subsequently validated by the case studies. Similarly, statistical analysis of the CrITIC data yielded measurable evidence that supported hypotheses derived from the framework, the case studies, and the writings of various experts. Besides providing an important mechanism of self-reinforcement and validation, the project's multifaceted nature made it possible to discern aspects of CI attack motivations that would likely have been missed if any single approach had been adopted.« less

  12. Design Space Approach in Optimization of Fluid Bed Granulation and Tablets Compression Process

    PubMed Central

    Djuriš, Jelena; Medarević, Djordje; Krstić, Marko; Vasiljević, Ivana; Mašić, Ivana; Ibrić, Svetlana

    2012-01-01

    The aim of this study was to optimize fluid bed granulation and tablets compression processes using design space approach. Type of diluent, binder concentration, temperature during mixing, granulation and drying, spray rate, and atomization pressure were recognized as critical formulation and process parameters. They were varied in the first set of experiments in order to estimate their influences on critical quality attributes, that is, granules characteristics (size distribution, flowability, bulk density, tapped density, Carr's index, Hausner's ratio, and moisture content) using Plackett-Burman experimental design. Type of diluent and atomization pressure were selected as the most important parameters. In the second set of experiments, design space for process parameters (atomization pressure and compression force) and its influence on tablets characteristics was developed. Percent of paracetamol released and tablets hardness were determined as critical quality attributes. Artificial neural networks (ANNs) were applied in order to determine design space. ANNs models showed that atomization pressure influences mostly on the dissolution profile, whereas compression force affects mainly the tablets hardness. Based on the obtained ANNs models, it is possible to predict tablet hardness and paracetamol release profile for any combination of analyzed factors. PMID:22919295

  13. Factors influencing sustainability of communally-managed water facilities in rural areas of Zimbabwe

    NASA Astrophysics Data System (ADS)

    Kativhu, T.; Mazvimavi, D.; Tevera, D.; Nhapi, I.

    2017-08-01

    Sustainability of point water facilities is a major development challenge in many rural settings of developing countries not sparing those in the Sub-Saharan Africa region. This study was done in Zimbabwe to investigate the factors influencing sustainability of rural water supply systems. A total of 399 water points were studied in Nyanga, Chivi and Gwanda districts. Data was collected using a questionnaire, observation checklist and key informant interview guide. Multi-Criteria analysis was used to assess the sustainability of water points and inferential statistical analysis such as Chi square tests and Analysis of Variance (ANOVA) were used to determine if there were significant differences on selected variables across districts and types of lifting devices used in the study area. The thematic approach was used to analyze qualitative data. Results show that most water points were not functional and only 17% across the districts were found to be sustainable. A fusion of social, technical, financial, environmental and institutional factors was found to be influencing sustainability. On technical factors the ANOVA results show that the type of lifting device fitted at a water point significantly influences sustainability (F = 37.4, p < 0.01). Availability of spare parts at community level was found to be determining the downtime period of different lifting devices in the studied wards. Absence of user committees was found to be central in influencing sustainability as water points that did not have user committees were not sustainable and most of them were not functional during the time of the survey. Active participation by communities at the planning stage of water projects was also found to be critical for sustainability although field results showed passive participation by communities at this critical project stage. Financial factors of adequacy of financial contributions and establishment of operation and maintenance funds were also found to be of great importance in sustaining water supply systems. It is recommended that all factors should be considered when assessing sustainability since they are interrelated.

  14. Determination of Parachute Joint Factors using Seam and Joint Testing

    NASA Technical Reports Server (NTRS)

    Mollmann, Catherine

    2015-01-01

    This paper details the methodology for determining the joint factor for all parachute components. This method has been successfully implemented on the Capsule Parachute Assembly System (CPAS) for the NASA Orion crew module for use in determining the margin of safety for each component under peak loads. Also discussed are concepts behind the joint factor and what drives the loss of material strength at joints. The joint factor is defined as a "loss in joint strength...relative to the basic material strength" that occurs when "textiles are connected to each other or to metals." During the CPAS engineering development phase, a conservative joint factor of 0.80 was assumed for each parachute component. In order to refine this factor and eliminate excess conservatism, a seam and joint testing program was implemented as part of the structural validation. This method split each of the parachute structural joints into discrete tensile tests designed to duplicate the loading of each joint. Breaking strength data collected from destructive pull testing was then used to calculate the joint factor in the form of an efficiency. Joint efficiency is the percentage of the base material strength that remains after degradation due to sewing or interaction with other components; it is used interchangeably with joint factor in this paper. Parachute materials vary in type-mainly cord, tape, webbing, and cloth -which require different test fixtures and joint sample construction methods. This paper defines guidelines for designing and testing samples based on materials and test goals. Using the test methodology and analysis approach detailed in this paper, the minimum joint factor for each parachute component can be formulated. The joint factors can then be used to calculate the design factor and margin of safety for that component, a critical part of the design verification process.

  15. Mathematical Models to Determine Stable Behavior of Complex Systems

    NASA Astrophysics Data System (ADS)

    Sumin, V. I.; Dushkin, A. V.; Smolentseva, T. E.

    2018-05-01

    The paper analyzes a possibility to predict functioning of a complex dynamic system with a significant amount of circulating information and a large number of random factors impacting its functioning. Functioning of the complex dynamic system is described as a chaotic state, self-organized criticality and bifurcation. This problem may be resolved by modeling such systems as dynamic ones, without applying stochastic models and taking into account strange attractors.

  16. Boys Go Fishing, Girls Work at Home: Gender Roles, Poverty and Unequal School Access among Semi-Nomadic Fishing Communities in South Western Madagascar

    ERIC Educational Resources Information Center

    Nascimento Moreira, Catarina; Rabenevanana, Man Wai; Picard, David

    2017-01-01

    Drawing from data gathered in South Western Madagascar in 2011, the work explores the combination of poverty and traditional gender roles as a critical factor in determining unequal school access among young people from semi-nomadic fishing communities. It demonstrates that from the age of early puberty, most boys go fishing with their fathers and…

  17. Analysis of Turkish Communications Sector and Determination of Critical Success Factors

    DTIC Science & Technology

    2014-09-01

    payments, video streaming, socializing, and online gaming , OTT providers can now easily provide mainstream services such as text messaging and voice...above the regional average as it has sufficient provisions for management of spectra. On the other hand, Ministry can imitate tenders for spectrum...which creates uncertainty about who will initiate tenders . Moreover, the ICTA is free to announce frequency allocation tenders openly and may decide to

  18. Overcoming Endocrine Resistance by Targeting ER/FoxA1/IL 8 Axis

    DTIC Science & Technology

    2016-10-01

    INTRODUCTION Approximately 75% of breast cancers express the hormone estrogen receptor α (ER). As a critical determinant in estrogen response and oncogenic...factor of estrogen receptor α (ER)–chromatin binding and function, yet its aberration in endocrine-resistant (Endo-R) breast cancer is unknown. Here, we...positive tumors. FOXA1 | estrogen receptor | breast cancer | transcriptional reprogramming | endocrine resistance About 75% of breast cancers express

  19. Public health, autonomous automobiles, and the rush to market.

    PubMed

    Kelley, Ben

    2017-05-01

    The USA has the worst motor vehicle safety problem among high-income countries and is pressing forward with the development of autonomous automobiles to address it. Government guidance and regulation, still inadequate, will be critical to the safety of the public. The analysis of this public health problem in the USA reveals the key factors that will determine the benefits and risks of autonomous vehicles around the world.

  20. Cell Therapy to Obtain Spinal Fusion

    DTIC Science & Technology

    2007-03-01

    2006. 38. Backesjo, C.M., Li, Y., Lindgren, U., and Haldosen, L.A. Activation of Sirt1 decreases adipocyte formation during osteoblast...However, in the whole blood samples with the same number of white cells, BMP2 activity was equal to the control suggesting that either the vector was... supplemented with 2% FBS, with antibiotic-antimycotic. Since we previously determined that the critical factor for inducing bone formation is the level

  1. Critical Success Factors for the North Carolina Community College System, 1999. Tenth Annual Report.

    ERIC Educational Resources Information Center

    North Carolina Community Coll. System, Raleigh.

    This report is one of several North Carolina Community College System accountability measures designed to report on critical success factors. Critical success factors are those issues that are instrumental for an institution to prosper and accomplish its goals. The data presented in this report are indicators of the "health" of the…

  2. Population Connectivity Measures of Fishery-Targeted Coral Reef Species to Inform Marine Reserve Network Design in Fiji

    PubMed Central

    Eastwood, Erin K.; López, Elora H.; Drew, Joshua A.

    2016-01-01

    Coral reef fish serve as food sources to coastal communities worldwide, yet are vulnerable to mounting anthropogenic pressures like overfishing and climate change. Marine reserve networks have become important tools for mitigating these pressures, and one of the most critical factors in determining their spatial design is the degree of connectivity among different populations of species prioritized for protection. To help inform the spatial design of an expanded reserve network in Fiji, we used rapidly evolving mitochondrial genes to investigate connectivity patterns of three coral reef species targeted by fisheries in Fiji: Epinephelus merra (Serranidae), Halichoeres trimaculatus (Labridae), and Holothuria atra (Holothuriidae). The two fish species, E. merra and Ha. trimaculatus, exhibited low genetic structuring and high amounts of gene flow, whereas the sea cucumber Ho. atra displayed high genetic partitioning and predominantly westward gene flow. The idiosyncratic patterns observed among these species indicate that patterns of connectivity in Fiji are likely determined by a combination of oceanographic and ecological characteristics. Our data indicate that in the cases of species with high connectivity, other factors such as representation or political availability may dictate where reserves are placed. In low connectivity species, ensuring upstream and downstream connections is critical. PMID:26805954

  3. Use of Combined Biogeochemical Model Approaches and Empirical Data to Assess Critical Loads of Nitrogen

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

    Fenn, Mark E.; Driscoll, Charles; Zhou, Qingtao

    2015-01-01

    Empirical and dynamic biogeochemical modelling are complementary approaches for determining the critical load (CL) of atmospheric nitrogen (N) or other constituent deposition that an ecosystem can tolerate without causing ecological harm. The greatest benefits are obtained when these approaches are used in combination. Confounding environmental factors can complicate the determination of empirical CLs across depositional gradients, while the experimental application of N amendments for estimating the CL does not realistically mimic the effects of chronic atmospheric N deposition. Biogeochemical and vegetation simulation models can provide CL estimates and valuable ecosystem response information, allowing for past and future scenario testing withmore » various combinations of environmental factors, pollutants, pollutant control options, land management, and ecosystem response parameters. Even so, models are fundamentally gross simplifications of the real ecosystems they attempt to simulate. Empirical approaches are vital as a check on simulations and CL estimates, to parameterize models, and to elucidate mechanisms and responses under real world conditions. In this chapter, we provide examples of empirical and modelled N CL approaches in ecosystems from three regions of the United States: mixed conifer forest, desert scrub and pinyon- juniper woodland in California; alpine catchments in the Rocky Mountains; and lakes in the Adirondack region of New York state.« less

  4. INTERNAL RADIATION DOSE MEASUREMENTS IN LIVE EXPERIMENTAL ANIMALS. PART II

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

    Nold, M.M.; Hayes, R.L.; Comar, C.L.

    1960-12-01

    Silver phosphate glass dosimeter rods were implanted in various portions of the digestive tract and the radiation dose was measured after ingestion of a known amount of Y/sup 90/. It was found that a state of diarrhea reduced the average radiation dose by a factor of from 2 to 4. In the constipated animal the dose was increased by a factor of from 3 to 7. Investigation was made to determine the role of various processes governing the radiation dose delivered to gastrointestinal mucosa. The total dose to a particular site along the intestinal tract was obtained by determination ofmore » the time integral of the radioactive concentration. Serial sacrifices were made at specific times after administration of the radioactivity. Calculations in this manner agreed exceptionally well with the doses that were measured by the glass dosimeter method. It is estimated that 4 and 17 - c of Y/sup 90/ for the dog and goat, respectively, will deliver a 300mrad dose to the critical organ, the lower large intestine. The twelve-fold average difference in dose between the diarrhea and constipation groups of dogs emphasizes the importance of the physical state of bowel passages upon the dose delivered to the critical organ. (auth)« less

  5. Bacterial Sigma Factors and Anti-Sigma Factors: Structure, Function and Distribution

    PubMed Central

    Paget, Mark S.

    2015-01-01

    Sigma factors are multi-domain subunits of bacterial RNA polymerase (RNAP) that play critical roles in transcription initiation, including the recognition and opening of promoters as well as the initial steps in RNA synthesis. This review focuses on the structure and function of the major sigma-70 class that includes the housekeeping sigma factor (Group 1) that directs the bulk of transcription during active growth, and structurally-related alternative sigma factors (Groups 2–4) that control a wide variety of adaptive responses such as morphological development and the management of stress. A recurring theme in sigma factor control is their sequestration by anti-sigma factors that occlude their RNAP-binding determinants. Sigma factors are then released through a wide variety of mechanisms, often involving branched signal transduction pathways that allow the integration of distinct signals. Three major strategies for sigma release are discussed: regulated proteolysis, partner-switching, and direct sensing by the anti-sigma factor. PMID:26131973

  6. Stakeholder conceptualisation of multi-level HIV and AIDS determinants in a Black epicentre.

    PubMed

    Brawner, Bridgette M; Reason, Janaiya L; Hanlon, Kelsey; Guthrie, Barbara; Schensul, Jean J

    2017-09-01

    HIV has reached epidemic proportions among African Americans in the USA but certain urban contexts appear to experience a disproportionate disease burden. Geographic information systems mapping in Philadelphia indicates increased HIV incidence and prevalence in predominantly Black census tracts, with major differences across adjacent communities. What factors shape these geographic HIV disparities among Black Philadelphians? This descriptive study was designed to refine and validate a conceptual model developed to better understand multi-level determinants of HIV-related risk among Black Philadelphians. We used an expanded ecological approach to elicit reflective perceptions from administrators, direct service providers and community members about individual, social and structural factors that interact to protect against or increase the risk for acquiring HIV within their community. Gender equity, social capital and positive cultural mores (e.g., monogamy, abstinence) were seen as the main protective factors. Historical negative contributory influences of racial residential segregation, poverty and incarceration were among the most salient risk factors. This study was a critical next step toward initiating theory-based, multi-level community-based HIV prevention initiatives.

  7. Change in Maternal Criticism and Behavior Problems in Adolescents and Adults with Autism Across a Seven-Year Period

    PubMed Central

    Baker, Jason K.; Smith, Leann E.; Greenberg, Jan S.; Seltzer, Marsha Mailick; Taylor, Julie Lounds

    2010-01-01

    In a previous study from our laboratory, high levels of maternal criticism predicted increased behavior problems in adolescents and adults with autism spectrum disorders (ASD) over an 18-month period (Greenberg, Seltzer, Hong, & Orsmond, 2006). The current investigation followed these families over a period of seven years to examine the longitudinal course of criticism and behavior problems, to assess the association between their trajectories, and to determine the degree to which change in each of these factors predicted levels of criticism and behavior problems at the end of the study period. A sample of 118 mothers co-residing with their adolescents and adults with ASD provided open-ended narratives about their children and reported on the children's behavior problems at four waves. Maternal criticism was derived from expressed emotion ratings of the narratives. Criticism exhibited low but significant stability over the seven year period and behavior problems exhibited high stability. Using latent growth curve modeling, (a) criticism was found to have increased over time, but only for the group of families in which the sons or daughters transitioned from high school services during the study period, (b) individual changes in criticism and behavior problems were positively correlated over the seven-year period, and (c) changes in criticism predicted levels of behavior problems at the conclusion of the study. Changes in behavior problems were not predictive of end levels of criticism. Implications for intervention and prevention efforts are discussed. PMID:21319925

  8. Uncertainty analysis on simple mass balance model to calculate critical loads for soil acidity.

    PubMed

    Li, Harbin; McNulty, Steven G

    2007-10-01

    Simple mass balance equations (SMBE) of critical acid loads (CAL) in forest soil were developed to assess potential risks of air pollutants to ecosystems. However, to apply SMBE reliably at large scales, SMBE must be tested for adequacy and uncertainty. Our goal was to provide a detailed analysis of uncertainty in SMBE so that sound strategies for scaling up CAL estimates to the national scale could be developed. Specifically, we wanted to quantify CAL uncertainty under natural variability in 17 model parameters, and determine their relative contributions in predicting CAL. Results indicated that uncertainty in CAL came primarily from components of base cation weathering (BC(w); 49%) and acid neutralizing capacity (46%), whereas the most critical parameters were BC(w) base rate (62%), soil depth (20%), and soil temperature (11%). Thus, improvements in estimates of these factors are crucial to reducing uncertainty and successfully scaling up SMBE for national assessments of CAL.

  9. Environmental endocrinology of salmon smoltification

    USGS Publications Warehouse

    Bjornsson, Bjorn Thrandur; Stefansson, S.O.; McCormick, S.D.

    2011-01-01

    Smolting is a hormone-driven developmental process that is adaptive for downstream migration and ocean survival and growth in anadromous salmonids. Smolting includes increased salinity tolerance, increased metabolism, downstream migratory and schooling behavior, silvering and darkened fin margins, and olfactory imprinting. These changes are promoted by growth hormone, insulin-like growth factor I, cortisol, thyroid hormones, whereas prolactin is inhibitory. Photoperiod and temperature are critical environmental cues for smolt development, and their relative importance will be critical in determining responses to future climate change. Most of our knowledge of the environmental control and endocrine mediation of smolting is based on laboratory and hatchery studies, yet there is emerging information on fish in the wild that indicates substantial differences. Such differences may arise from differences in environmental stimuli in artificial rearing environments, and may be critical to ocean survival and population sustainability. Endocrine disruptors, acidification and other contaminants can perturb smolt development, resulting in poor survival after seawater entry. ?? 2010.

  10. Impact of a critical pathway on postoperative length of stay and outcomes after infrainguinal bypass.

    PubMed

    Stanley, A C; Barry, M; Scott, T E; LaMorte, W W; Woodson, J; Menzoian, J O

    1998-06-01

    To determine the effect of a critical pathway on postoperative length of stay and outcomes after infrainguinal bypass. A critical pathway for care of patients after infrainguinal bypass was introduced in December 1995 to coordinate postoperative care at our institution. We compared care of 67 consecutively treated patients before institution of the pathway with care of 69 consecutively treated patients with the critical pathway in place. Data collection was done by means of chart review. Univariate analyses were used to identify differences between prepathway and postpathway patients and to identify factors influencing postoperative length of stay. Multivariate analysis was used to identify factors that influenced length of stay and to examine the effect of use of the pathway after adjusting for other factors. Patients on the pathway were similar to prepathway controls with respect to comorbid illnesses, vascular risk factors, indications for surgical treatment, type of conduit, and type of operation. Factors associated with longer postoperative stays included distal anastomoses to tibial rather than popliteal vessels (p = 0.02), preexisting cardiac disease (p = 0.005), postoperative complications (p = 0.0003), lower preoperative hematocrit (p = 0.01), and elevated preoperative creatinine level (p = 0.006). Overall, pathway patients had somewhat shorter postoperative lengths of stay (median value 7 days; range 2 to 29 days) than prepathway patients (median value 6 days; range 2 to 35; p = 0.01), and the two groups had similar frequencies of postoperative complications, readmission, and 6-month mortality. However, patients on the pathway were more likely to be discharged to an intermediate-care facility rather than directly home. After 12 patients with extraordinarily prolonged postoperative stays were excluded, multivariate analysis indicated that pathway patients had significantly shorter postoperative stays (p = 0.001). However, the difference was not significant if patients with extraordinarily long postoperative stays were included in the analysis (p = 0.28). Use of a critical pathway was associated with a modest decrease in postoperative length of stay for most patients. This was accomplished without an adverse effect on readmission, complication, or mortality rates. However, the decrease in stay may have been achieved primarily by discharging more patients to intermediate-care facilities. The pathway did not appear to have any effect when the subset of patients with extraordinarily long stays because of complex medical problems was included.

  11. Factors influencing perceived angular velocity.

    PubMed

    Kaiser, M K; Calderone, J B

    1991-11-01

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

  12. Exploring the association between parental rearing styles and medical students' critical thinking disposition in China.

    PubMed

    Huang, Lei; Wang, Zhaoxin; Yao, Yuhong; Shan, Chang; Wang, Haojie; Zhu, Mengyi; Lu, Yuan; Sun, Pengfei; Zhao, Xudong

    2015-05-14

    Critical thinking is an essential ability for medical students. However, the relationship between parental rearing styles and medical students' critical thinking disposition has rarely been considered. The aim of this study was to investigate whether parental rearing styles were significant predictors of critical thinking disposition among Chinese medical students. 1,075 medical students from the first year to the fifth year attending one of three medical schools in China were recruited via multistage stratified cluster sampling. The Chinese Critical Thinking Disposition Inventory(CTDI-CV) and The Egna Minnen av Barndoms Uppfostran (EMBU) questionnaire were applied to collect data and to conduct descriptive analysis. Stepwise multiple linear regression was used to analyze the data. The critical thinking disposition average mean score was 287.44 with 632 participants (58.79%) demonstrating positive critical thinking disposition. Stepwise multiple linear regression analysis revealed that the rearing styles of fathers, including "overprotection", "emotional warmth and understanding", "rejection" and "over-interference" were significant predictors of medical students' critical thinking disposition that explained 79.0% of the variance in critical thinking ability. Rearing styles of mothers including "emotional warmth and understanding", "punishing" and "rejection" were also found to be significant predictors, and explained 77.0% of the variance. Meaningful association has been evidenced between parental rearing styles and Chinese medical students' critical thinking disposition. Parental rearing styles should be considered as one of the many potential determinant factors that contribute to the cultivation of medical students' critical thinking capability. Positive parental rearing styles should be encouraged in the cultivation of children's critical thinking skills.

  13. Developing a suitable model for supplier selection based on supply chain risks: an empirical study from Iranian pharmaceutical companies.

    PubMed

    Mehralian, Gholamhossein; Rajabzadeh Gatari, Ali; Morakabati, Mohadese; Vatanpour, Hossein

    2012-01-01

    The supply chain represents the critical link between the development of new product and the market in pharmaceutical industry. Over the years, improvements made in supply chain operations have focused largely on ways to reduce cost and gain efficiencies in scale. In addition, powerful regulatory and market forces have provided new incentives for pharmaceutical firms to basically rethink the way they produce and distribute products, and also to re-imagine the role of the supply chain in driving strategic growth, brand differentiation and economic value in the health continuum. The purpose of this paper is to formulate basic factors involved in risk analysis of pharmaceutical industry, and also determine the effective factors involved in suppliers selection and their priorities. This paper is based on the results of literature review, experts' opinion acquisition, statistical analysis and also using MADM models on data gathered from distributed questionnaires. The model consists of the following steps and components: first factors involved in to supply chain risks are determined. Based on them a framework is considered. According the result of statistical analysis and MADM models the risk factors are formulated. The paper determines the main components and influenceial factors involving in the supply chain risks. Results showed that delivery risk can make an important contribution to mitigate the risk of pharmaceutical industry.

  14. Developing a Suitable Model for Supplier Selection Based on Supply Chain Risks: An Empirical Study from Iranian Pharmaceutical Companies

    PubMed Central

    Mehralian, Gholamhossein; Rajabzadeh Gatari, Ali; Morakabati, Mohadese; Vatanpour, Hossein

    2012-01-01

    The supply chain represents the critical link between the development of new product and the market in pharmaceutical industry. Over the years, improvements made in supply chain operations have focused largely on ways to reduce cost and gain efficiencies in scale. In addition, powerful regulatory and market forces have provided new incentives for pharmaceutical firms to basically rethink the way they produce and distribute products, and also to re-imagine the role of the supply chain in driving strategic growth, brand differentiation and economic value in the health continuum. The purpose of this paper is to formulate basic factors involved in risk analysis of pharmaceutical industry, and also determine the effective factors involved in suppliers selection and their priorities. This paper is based on the results of literature review, experts’ opinion acquisition, statistical analysis and also using MADM models on data gathered from distributed questionnaires. The model consists of the following steps and components: first factors involved in to supply chain risks are determined. Based on them a framework is considered. According the result of statistical analysis and MADM models the risk factors are formulated. The paper determines the main components and influenceial factors involving in the supply chain risks. Results showed that delivery risk can make an important contribution to mitigate the risk of pharmaceutical industry. PMID:24250442

  15. Theoretical Insight Into the Empirical Tortuosity-Connectivity Factor in the Burdine-Brooks-Corey Water Relative Permeability Model

    NASA Astrophysics Data System (ADS)

    Ghanbarian, Behzad; Ioannidis, Marios A.; Hunt, Allen G.

    2017-12-01

    A model commonly applied to the estimation of water relative permeability krw in porous media is the Burdine-Brooks-Corey model, which relies on a simplified picture of pores as a bundle of noninterconnected capillary tubes. In this model, the empirical tortuosity-connectivity factor is assumed to be a power law function of effective saturation with an exponent (μ) commonly set equal to 2 in the literature. Invoking critical path analysis and using percolation theory, we relate the tortuosity-connectivity exponent μ to the critical scaling exponent t of percolation that characterizes the power law behavior of the saturation-dependent electrical conductivity of porous media. We also discuss the cause of the nonuniversality of μ in terms of the nonuniversality of t and compare model estimations with water relative permeability from experiments. The comparison supports determining μ from the electrical conductivity scaling exponent t, but also highlights limitations of the model.

  16. Microbiological concerns and methodological approaches related to bacterial water quality in spaceflight

    NASA Technical Reports Server (NTRS)

    Pyle, Barry H.; Mcfeters, Gordon A.

    1992-01-01

    A number of microbiological issues are of critical importance to crew health and system performance in spacecraft water systems. This presentation reviews an army of these concerns which include factors that influence water treatment and disinfection in spaceflight such as biofilm formation and the physiological responses of bacteria in clean water systems. Factors associated with spaceflight like aerosol formation under conditions of microgravity are also discussed within the context of airborne infections such as Legionellosis. Finally, a spectrum of analytical approaches is reviewed to provide an evaluation of methodological alternatives that have been suggested or used to detect microorganisms of interest in water systems. These range from classical approaches employing colony formation on specific microbiological growth media to direct (i.e. microscopic) and indirect (e.g. electrochemical) methods as well as the use of molecular approaches and gene probes. These techniques are critically evaluated for their potential utility in determining microbiological water quality through the detection of microorganisms under the influence of ambient environmental stress inherent in spaceflight water systems.

  17. 2010 Critical Success Factors for the North Carolina Community College System. Twenty First Annual Report

    ERIC Educational Resources Information Center

    North Carolina Community College System (NJ1), 2010

    2010-01-01

    First mandated by the North Carolina General Assembly in 1989 (S.L. 1989; C. 752; S. 80), the Critical Success Factors report has evolved into the major accountability document for the North Carolina Community College System. This twenty first annual report on the critical success factors is the result of a process undertaken to streamline and…

  18. Determinants of Obesity and Associated Population Attributability, South Africa: Empirical Evidence from a National Panel Survey, 2008-2012

    PubMed Central

    Sartorius, Benn; Veerman, Lennert J.; Manyema, Mercy; Chola, Lumbwe; Hofman, Karen

    2015-01-01

    Background Obesity is a major risk factor for emerging non-communicable diseases (NCDS) in middle income countries including South Africa (SA). Understanding the multiple and complex determinants of obesity and their true population attributable impact is critical for informing and developing effective prevention efforts using scientific based evidence. This study identified contextualised high impact factors associated with obesity in South Africa. Methods Analysis of three national cross sectional (repeated panel) surveys, using a multilevel logistic regression and population attributable fraction estimation allowed for identification of contextualised high impact factors associated with obesity (BMI>30 kg/m2) among adults (15years+). Results Obesity prevalence increased significantly from 23.5% in 2008 to 27.2% in 2012, with a significantly (p-value<0.001) higher prevalence among females (37.9% in 2012) compared to males (13.3% in 2012). Living in formal urban areas, white ethnicity, being married, not exercising and/or in higher socio-economic category were significantly associated with male obesity. Females living in formal or informal urban areas, higher crime areas, African/White ethnicity, married, not exercising, in a higher socio-economic category and/or living in households with proportionate higher spending on food (and unhealthy food options) were significantly more likely to be obese. The identified determinants appeared to account for 75% and 43% of male and female obesity respectively. White males had the highest relative gain in obesity from 2008 to 2012. Conclusions The rising prevalence of obesity in South Africa is significant and over the past 5 years the rising prevalence of Type-2 diabetes has mirrored this pattern, especially among females. Targeting young adolescent girls should be a priority. Addressing determinants of obesity will involve a multifaceted strategy and requires at individual and population levels. With rising costs in the private and public sector to combat obesity related NCDS, this analysis can inform culturally sensitive mass communications and wellness campaigns. Knowledge of social determinants is critical to develop “best buys”. PMID:26061419

  19. Asymptotic behaviour of two-point functions in multi-species models

    NASA Astrophysics Data System (ADS)

    Kozlowski, Karol K.; Ragoucy, Eric

    2016-05-01

    We extract the long-distance asymptotic behaviour of two-point correlation functions in massless quantum integrable models containing multi-species excitations. For such a purpose, we extend to these models the method of a large-distance regime re-summation of the form factor expansion of correlation functions. The key feature of our analysis is a technical hypothesis on the large-volume behaviour of the form factors of local operators in such models. We check the validity of this hypothesis on the example of the SU (3)-invariant XXX magnet by means of the determinant representations for the form factors of local operators in this model. Our approach confirms the structure of the critical exponents obtained previously for numerous models solvable by the nested Bethe Ansatz.

  20. Tunable Q-Factor RF Cavity

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

    Balcazar, Mario D.; Yonehara, Katsuya; Moretti, Alfred

    Intense neutrino beam is a unique probe for researching beyond the standard model. Fermilab is the main institution to produce the most powerful and widespectrum neutrino beam. From that respective, a radiation robust beam diagnostic system is a critical element in order to maintain the quality of the neutrino beam. Within this context, a novel radiation-resistive beam profile monitor based on a gasfilled RF cavity is proposed. The goal of this measurement is to study a tunable Qfactor RF cavity to determine the accuracy of the RF signal as a function of the quality factor. Specifically, measurement error of themore » Q-factor in the RF calibration is investigated. Then, the RF system will be improved to minimize signal error.« less

  1. Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano, Hawaii: Field observations and key factors

    USGS Publications Warehouse

    Peterson, Donald W.; Tilling, Robert I.

    1980-01-01

    Nearly all Hawaiian basaltic lava erupts as pahoehoe, and some changes to aa during flowage and cooling; factors governing the transition involve certain critical relations between viscosity and rate of shear strain. If the lava slows, cools, and stops in direct response to concomitant increase in viscosity before these critical relations are reached, it remains pahoehoe. But, if flow mechanics (flow rate, flow dimensions, slope, momentum, etc.) impel the lava to continue to move and deform even after it has become highly viscous, the critical relations may be reached and the lava changes to aa.Typical modes of transition from pahoehoe to aa include: (1) spontaneous formation of relatively stiff clots in parts of the flowing lava where shear rate is highest; these clots grow into discrete, rough, sticky masses to which the remaining fluid lava incrementally adheres; (2) fragmentation and immersion of solid or semi-solid surface crusts of pahoehoe by roiling movements of the flow, forming cores of discrete, tacky masses; (3) sudden renewed movement of lava stored and cooled within surface reservoirs to form clots. The masses, fragments, and clots in these transition modes are characterized by spinose, granulated surfaces; as flow movement continues, the masses and fragments aggregate, fracture, and grind together, completing the transition to aa.Observations show that the critical relation between viscosity and rate of shear strain is inverse: if viscosity is low, a high rate of shear is required to begin the transition to aa; conversely, if viscosity is high, a much lower rate of shear will induce the transition. These relations can be demonstrated qualitatively with simple graphs, which can be used to examine the flow history of any selected finite lava element by tracing the path represented by its changing viscosity and shear rate. A broad, diffuse “transition threshold zone” in these graphs portrays the inverse critical relation between viscosity and shear rate; the transition to aa is represented by the path of the lava element crossing this zone.Moving lava flows can be regarded as natural viscometers, by which shear stress and rate of shear strain at selected points can be determined and viscosity can be computed. By making such determinations under a wide range of conditions on pahoehoe, aa, and transitional flow types, the critical relations that control the pahoehoe-aa transition can be quantified.

  2. Teaching critical health literacy in the US as a means to action on the social determinants of health

    PubMed Central

    Mogford, Elizabeth; Gould, Linn; DeVoght, Andra

    2011-01-01

    In spite of improvements in global health over the 20th century, health inequities are increasing. Mounting evidence suggests that reducing health inequities requires taking action on the social determinants of health (SDOH), which include income, education, employment, political empowerment and other factors. This paper introduces an alternative health education curriculum, developed by the US-based non-profit organization Just Health Action, which teaches critical health literacy as a step towards empowering people to achieve health equity. Critical health literacy is defined as an individual's understanding of the SDOH combined with the skills to take action at both the individual and the community level. Prior to describing our curricular framework, we connect the recommendations of the World Health Organization Commission on the SDOH with the objectives of the Ottawa Charter for Health Promotion by arguing that achieving them is reliant on critical health literacy. Then we describe our four-part curricular framework for teaching critical health literacy. Part 1, Knowledge, focuses on teaching the SDOH and the paradigm of health as a human right. Part 2, Compass, refers to activities that help students find their own direction as a social change agent. Part 3, Skills, refers to teaching specific advocacy tools and strategies. Part 4, Action, refers to the development and implementation of an action intended to increase health equity by addressing the SDOH. We describe activities that we use to motivate, engage and empower students to take action on the SDOH and provide examples of advocacy skills students have learned and actions they have implemented. PMID:20729240

  3. Incidence and predictors of critical events during urgent air–medical transport

    PubMed Central

    Singh, Jeffrey M.; MacDonald, Russell D.; Bronskill, Susan E.; Schull, Michael J.

    2009-01-01

    Background Little is known about the risks of urgent air–medical transport used in regionalized health care systems. We sought to determine the incidence of intransit critical events and identify factors associated with these events. Methods We conducted a population-based, retrospective cohort study using clinical and administrative data. We included all adults undergoing urgent air–medical transport in the Canadian province of Ontario between Jan. 1, 2004, and May 31, 2006. The primary outcome was in-transit critical events, which we defined as death, major resuscitative procedure, hemodynamic deterioration, or inadvertent extubation or respiratory arrest. Results We identified 19 228 patients who underwent air–medical transport during the study period. In-transit critical events were observed in 5.1% of all transports, for a rate of 1 event per 12.6 hours of transit time. Events consisted primarily of new hypotension or airway management procedures. Independent predictors of critical events included female sex (adjusted odds ratio [OR] 1.3, 95% confidence interval [CI] 1.1–1.5), assisted ventilation before transport (adjusted OR 3.0, 95% CI 2.3–3.7), hemodynamic instability before transport (adjusted OR 3.2, 95% CI 2.5–4.1), transport in a fixed-wing aircraft (adjusted OR 1.5, 95% CI 1.2–1.8), increased duration of transport (adjusted OR 1.02 per 10-minute increment, 95% CI 1.01–1.03), on-scene calls (adjusted OR 1.7, 95% CI 1.4–2.1) and type of crew (adjusted OR 0.6 for advanced care paramedics v. critical care paramedics, 95% CI 0.5–0.7). Interpretation Critical events occurred in about 1 in every 20 air–medical transports and were associated with multiple risk factors at the patient, transport and system levels. These findings have implications for the refinement of training of paramedic transport crews and processes for triage and transport. PMID:19752105

  4. Determination of the distribution constants of aromatic compounds and steroids in biphasic micellar phosphonium ionic liquid/aqueous buffer systems by capillary electrokinetic chromatography.

    PubMed

    Lokajová, Jana; Railila, Annika; King, Alistair W T; Wiedmer, Susanne K

    2013-09-20

    The distribution constants of some analytes, closely connected to the petrochemical industry, between an aqueous phase and a phosphonium ionic liquid phase, were determined by ionic liquid micellar electrokinetic chromatography (MEKC). The phosphonium ionic liquids studied were the water-soluble tributyl(tetradecyl)phosphonium with chloride or acetate as the counter ion. The retention factors were calculated and used for determination of the distribution constants. For calculating the retention factors the electrophoretic mobilities of the ionic liquids were required, thus, we adopted the iterative process, based on a homologous series of alkyl benzoates. Calculation of the distribution constants required information on the phase-ratio of the systems. For this the critical micelle concentrations (CMC) of the ionic liquids were needed. The CMCs were calculated using a method based on PeakMaster simulations, using the electrophoretic mobilities of system peaks. The resulting distribution constants for the neutral analytes between the ionic liquid and the aqueous (buffer) phase were compared with octanol-water partitioning coefficients. The results indicate that there are other factors affecting the distribution of analytes between phases, than just simple hydrophobic interactions. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Exercise, Hormones, and Skeletal Adaptations During Childhood and Adolescence

    PubMed Central

    Farr, Joshua N.; Laddu, Deepika R.; Going, Scott B.

    2015-01-01

    Although primarily considered a disorder of the elderly, emerging evidence suggests the antecedents of osteoporosis are established during childhood and adolescence. A complex interplay of genetic, environmental, hormonal and behavioral factors determines skeletal development, and a greater effort is needed to identify the most critical factors that establish peak bone strength. Indeed, knowledge of modifiable factors that determine skeletal development may permit optimization of skeletal health during growth and could potentially offset reductions in bone strength with aging. The peripubertal years represent a unique period when the skeleton is particularly responsive to loading exercises, and there is now overwhelming evidence that exercise can optimize skeletal development. While this is not controversial, the most effective exercise prescription and how much investment in this prescription is needed to significantly impact bone health continues to be debated. Despite considerable progress, these issues are not easy to address, and important questions remain unresolved. This review focuses on the key determinants of skeletal development, whether exercise during childhood and adolescence should be advocated as a safe and effective strategy for optimizing peak bone strength, and whether investment in exercise early in life protects against the development of osteoporosis and fractures later in life. PMID:25372373

  6. Budding Capability of the Influenza Virus Neuraminidase Can Be Modulated by Tetherin▿

    PubMed Central

    Yondola, Mark A.; Fernandes, Fiona; Belicha-Villanueva, Alan; Uccelini, Melissa; Gao, Qinshan; Carter, Carol; Palese, Peter

    2011-01-01

    We have determined that, in addition to its receptor-destroying activity, the influenza virus neuraminidase is capable of efficiently forming virus-like particles (VLPs) when expressed individually from plasmid DNA. This observation applies to both human subtypes of neuraminidase, N1 and N2. However, it is not found with every strain of influenza virus. Through gain-of-function and loss-of-function analyses, a critical determinant within the neuraminidase ectodomain was identified that contributes to VLP formation but is not sufficient to accomplish release of plasmid-derived VLPs. This sequence lies on the plasma membrane-proximal side of the neuraminidase globular head. Most importantly, we demonstrate that the antiviral restriction factor tetherin plays a role in determining the strain-specific limitations of release competency. If tetherin is counteracted by small interfering RNA knockdown or expression of the HIV anti-tetherin factor vpu, budding and release capability is bestowed upon an otherwise budding-deficient neuraminidase. These data suggest that budding-competent neuraminidase proteins possess an as-yet-unidentified means of counteracting the antiviral restriction factor tetherin and identify a novel way in which the influenza virus neuraminidase can contribute to virus release. PMID:21209114

  7. USSR and Eastern Europe Scientific Abstracts, Materials Science and Metallurgy, Number 45

    DTIC Science & Technology

    1977-05-11

    constants VQ and q. The values of the critical stress intensity factor produced by the authors by their indirect method are compared with...and TEREKHOV, A. N., Moscow Institute of Steel and Alloys [Russian abstract provided by the source] [Text] The method of high-temperature...their melting point. References 9; all Russian. USSR ’ UDC 539𔃽 IMPROVING THE PRECISION OF THE ACOUSTIC METHOD OF STRESS DETERMINATION Kiev

  8. Determination of Critical Achievement Factors in Distance Education by Using Structural Equality Model: A Case Study of E-MBA Program Held in Sakarya University

    ERIC Educational Resources Information Center

    Evirgen, Hayrettin; Cengel, Metin

    2012-01-01

    Nowadays, distance learning education has started to become familiar in behalf of classical face to face education (F2F) model. Web based learning is a major part of distance education systems. Web based distance learning can be defined shortly as an education type which doesn't force students and educators being into the same mediums. This…

  9. U.S. Budgeting for the United Nations: Process, Policy, and Problems

    DTIC Science & Technology

    2009-06-01

    Committees play the critical roles in determining U.S. funding for the UN. UN procurement and internal management reform, abortion , the Human Rights Council...internal management reform, abortion , the Human Rights Council, and the degree of U.S. influence in the UN have been significant factors affecting...corruption exist in the UN is the attempt to balance UN Secretariat representation based on nationality, sex , and type of appointment, taking into account

  10. Fluid Mechanical Properties of Silkworm Fibroin Solutions

    NASA Astrophysics Data System (ADS)

    Matsumoto, Akira

    2005-11-01

    The aqueous solution behavior of silk fibroin is of interest due to the assembly and processing of this protein related to the spinning of protein fibers that exhibit remarkable mechanical properties. To gain insight into the origins of this functional feature, it is desired to determine how the protein behaves under a range of solution conditions. Pure fibroin at different concentrations in water was studied for surface tension, as a measure of surfactancy. In addition, shear induced changes on these solutions in terms of structure and morphology was also determined. Fibroin solutions exhibited shear rate-sensitive viscosity changes and precipitated at a critical shear rate where a dramatic increase of 75-150% of the initial value was observed along with a decrease in viscosity. In surface tension measurements, critical micelle concentrations were in the range of 3-4% w/v. The influence of additional factors, such as sericin protein, divalent and monovalent cations, and pH on the solution behavior in relation to structural and morphological features will also be described.

  11. A secreted bacterial protease tailors the Staphylococcus aureus virulence repertoire to modulate bone remodeling during osteomyelitis

    PubMed Central

    Cassat, James E.; Hammer, Neal D.; Campbell, J. Preston; Benson, Meredith A.; Perrien, Daniel S.; Mrak, Lara N.; Smeltzer, Mark S.; Torres, Victor J.; Skaar, Eric P.

    2013-01-01

    Summary Osteomyelitis is a common manifestation of invasive Staphylococcus aureus infection. Pathogen-induced bone destruction limits antimicrobial penetration to the infectious focus and compromises treatment of osteomyelitis. To investigate mechanisms of S. aureus-induced bone destruction, we developed a murine model of osteomyelitis. Micro-computed tomography of infected femurs revealed that S. aureus triggers profound alterations in bone turnover. The bacterial regulatory locus sae was found to be critical for osteomyelitis pathogenesis, as Sae-regulated factors promote pathologic bone remodeling and intraosseous bacterial survival. Exoproteome analyses revealed the Sae-regulated protease aureolysin as a major determinant of the S. aureus secretome and identified the phenol soluble modulins as aureolysin-degraded, osteolytic peptides that trigger osteoblast cell death and bone destruction. These studies establish a murine model for pathogen-induced bone remodeling, define Sae as critical for osteomyelitis pathogenesis, and identify protease-dependent exoproteome remodeling as a major determinant of the staphylococcal virulence repertoire. PMID:23768499

  12. Predictors and variation of routine home discharge in critically ill adults with cystic fibrosis.

    PubMed

    Oud, Lavi; Chan, Yiu Ming

    2018-06-01

    The short-term outcomes of patients with cystic fibrosis (CF) surviving critical illness were not examined systematically. To determine the factors associated with and variation in rates of routine home discharge among ICU-managed adult CF patients. Predictors of routine home discharge and its hospital-level variation were examined in ICU-managed adults with cystic fibrosis in Texas during 2004-2013. Older age, rural residence, and severity of illness decreased odds of routine home discharge, while hospitalization in facilities accredited as part of the Cystic Fibrosis Foundation Care Center Network nearly doubled the odds of routine home discharge. The median (interquartile) adjusted rate of routine home discharge was 62.0% (31.5-82.5). The identified determinants of routine home discharge can inform clinical decision-making, while the demonstrated wide variation in adjusted across-hospital rates of routine home discharge of ICU-managed adults with CF can provide benchmark data for future quality improvement efforts. Published by Elsevier Inc.

  13. Usefulness of LANDSAT data for monitoring plant development and range conditions in California's annual grassland

    NASA Technical Reports Server (NTRS)

    Carneggie, D. M.; Degloria, S. D.; Colwell, R. N.

    1975-01-01

    A network of sampling sites throughout the annual grassland region of California was established to correlate plant growth stages and forage production to climatic and other environmental factors. Plant growth and range conditions were further related to geographic location and seasonal variations. A sequence of LANDSAT data was obtained covering critical periods in the growth cycle. This was analyzed by both photointerpretation and computer aided techniques. Image characteristics and spectral reflectance data were then related to forage production, range condition, range site and changing growth conditions. It was determined that repeat sequences with LANDSAT color composite images do provide a means for monitoring changes in range condition. Spectral radiance data obtained from magnetic tape can be used to determine quantitatively the critical stages in the forage growth cycle. A computer ratioing technique provided a sensitive indicator of changes in growth stages and an indication of the relative differences in forage production between range sites.

  14. Clinical review: Ethics and end-of-life care for critically ill patients in China.

    PubMed

    Li, Li Bin

    2013-12-04

    Critical care medicine in China has made great advances in recent decades. This has led to an unavoidable issue: end-of-life ethics. With advances in medical technology and therapeutics allowing the seemingly limitless maintenance of life, the exact time of death of an individual patient is often determined by the decision to limit life support. How to care for patients at the end of life is not only a medical problem but also a social, ethical, and legal issue. A lot of factors, besides culture, come into play in determining a person's ethical attitudes or behaviors, such as experience, education, religion, individual attributes, and economic considerations. Chinese doctors face ethical problems similar to those of their Western counterparts; however, since Chinese society is different from that of Western countries in cultural traditions, customs, religious beliefs, and ethnic backgrounds, there is a great difference between China and the Western world in regard to ethics at the end of life, and there is also a huge controversy within China.

  15. The Role of Bacterial Protein Tyrosine Phosphatases in the Regulation of the Biosynthesis of Secreted Polysaccharides

    PubMed Central

    Morona, Renato

    2014-01-01

    Abstract Significance: Tyrosine phosphorylation and associated protein tyrosine phosphatases are gaining prominence as critical mechanisms in the regulation of fundamental processes in a wide variety of bacteria. In particular, these phosphatases have been associated with the control of the biosynthesis of capsular polysaccharides and extracellular polysaccharides, critically important virulence factors for bacteria. Recent Advances: Deletion and overexpression of the phosphatases result in altered polysaccharide biosynthesis in a range of bacteria. The recent structures of associated auto-phosphorylating tyrosine kinases have suggested that the phosphatases may be critical for the cycling of the kinases between monomers and higher order oligomers. Critical Issues: Additional substrates of the phosphatases apart from cognate kinases are currently being identified. These are likely to be critical to our understanding of the mechanism by which polysaccharide biosynthesis is regulated. Future Directions: Ultimately, these protein tyrosine phosphatases are an attractive target for the development of novel antimicrobials. This is particularly the case for the polymerase and histidinol phosphatase family, which is predominantly found in bacteria. Furthermore, the determination of bacterial tyrosine phosphoproteomes will likely help to uncover the fundamental roles, mechanism, and critical importance of these phosphatases in a wide range of bacteria. Antioxid. Redox Signal. 20, 2274–2289. PMID:24295407

  16. The critical role of personality and organizational factors as determinants of reactions to restricted and stressful environments. [undersea habitats

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.

    1987-01-01

    Research into the impact of personality factors on groups in various settings is reviewed as an introduction to a brief discussion of personality and group behavior research needs relevant to the space program. Significant findings of some earlier research are summarized, and methodological problems are touched on. The study of intergroup and intragroup conflict in a stressful environment, as exemplified particularly by undersea habitats, is seen as being of consequence for long-term space missions. It is concluded that adequate research can only be conducted as an adjunct to data collection from operational stressful environments, and not from laboratory experiments.

  17. Bioconcentration

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

    Barron, M.G.

    1990-11-01

    Bioconcentration is the process of accumulation of water-borne chemicals by fish and other aquatic animals through nondietary routes. A proportionality constant relating the concentration of a chemical in water to its concentration in the aquatic animal at steady-state equilibrium is the bioconcentration factor (BCF). The purpose of this paper is to critically evaluate the hypothesis that hydrophobicity is the principal determinant of bioconcentration in aquatic animals and examine the dependence of bioconcentration on species, body size, and environmental factors. BCFs for a variety of chemical classes are evaluated for their conformity to the hydrophobicity model of bioconcentration, and an alternativemore » conceptual model of bioconcentration incorporating animal physiology is presented.« less

  18. The Lewisian turning point and international migration: the case of Japan.

    PubMed

    Watanabe, S

    1994-01-01

    "This article critically examines the Lewisian turning point [concerning the availability of unlimited manpower resources] in light of Japan's experience since the mid-1800s. Japan reached its Lewisian turning point around 1960. Contrary to the assumptions of the theory however, the findings for Japan indicate that political factors have been more determinative of the rate of migration than purely economic ones. Prior to its turning point in 1960, international relations, war and forced repatriation were the decisive factors. Recently, though the inflow of foreign workers to fill labor shortages has increased, so also has the outflow of Japanese to accompany direct foreign investment." excerpt

  19. Factors associated with seasonal influenza vaccination in pregnant women.

    PubMed

    Henninger, Michelle L; Irving, Stephanie A; Thompson, Mark; Avalos, Lyndsay Ammon; Ball, Sarah W; Shifflett, Pat; Naleway, Allison L

    2015-05-01

    This observational study followed a cohort of pregnant women during the 2010-2011 influenza season to determine factors associated with vaccination. Participants were 1105 pregnant women who completed a survey assessing health beliefs related to vaccination upon enrollment and were then followed to determine vaccination status by the end of the 2010-2011 influenza season. We conducted univariate and multivariate analyses to explore factors associated with vaccination status and a factor analysis of survey items to identify health beliefs associated with vaccination. Sixty-three percent (n=701) of the participants were vaccinated. In the univariate analyses, multiple factors were associated with vaccination status, including maternal age, race, marital status, educational level, and gravidity. Factor analysis identified two health belief factors associated with vaccination: participant's positive views (factor 1) and negative views (factor 2) of influenza vaccination. In a multivariate logistic regression model, factor 1 was associated with increased likelihood of vaccination (adjusted odds ratio [aOR]=2.18; 95% confidence interval [CI]=1.72-2.78), whereas factor 2 was associated with decreased likelihood of vaccination (aOR=0.36; 95% CI=0.28-0.46). After controlling for the two health belief factors in multivariate analyses, demographic factors significant in univariate analyses were no longer significant. Women who received a provider recommendation were about three times more likely to be vaccinated (aOR=3.14; 95% CI=1.99-4.96). Pregnant women's health beliefs about vaccination appear to be more important than demographic and maternal factors previously associated with vaccination status. Provider recommendation remains one of the most critical factors influencing vaccination during pregnancy.

  20. Micromechanics Modeling of Fracture in Nanocrystalline Metals

    NASA Technical Reports Server (NTRS)

    Glaessgen, E. H.; Piascik, R. S.; Raju, I. S.; Harris, C. E.

    2002-01-01

    Nanocrystalline metals have very high theoretical strength, but suffer from a lack of ductility and toughness. Therefore, it is critical to understand the mechanisms of deformation and fracture of these materials before their full potential can be achieved. Because classical fracture mechanics is based on the comparison of computed fracture parameters, such as stress intlmsity factors, to their empirically determined critical values, it does not adequately describe the fundamental physics of fracture required to predict the behavior of nanocrystalline metals. Thus, micromechanics-based techniques must be considered to quanti@ the physical processes of deformation and fracture within nanocrystalline metals. This paper discusses hndamental physicsbased modeling strategies that may be useful for the prediction Iof deformation, crack formation and crack growth within nanocrystalline metals.

  1. Inhibition of IRF-3 activation by VP35 is critical for the high level of virulence of ebola virus.

    PubMed

    Hartman, Amy L; Bird, Brian H; Towner, Jonathan S; Antoniadou, Zoi-Anna; Zaki, Sherif R; Nichol, Stuart T

    2008-03-01

    Zaire ebolavirus causes a rapidly progressing hemorrhagic disease with high mortality. Identification of the viral virulence factors that contribute to the severity of disease induced by Ebola virus is critical for the design of therapeutics and vaccines against the disease. Given the rapidity of disease progression, virus interaction with the innate immune system early in the course of infection likely plays an important role in determining the outcome of the disease. The Ebola virus VP35 protein inhibits the activation of IRF-3, a critical transcription factor for the induction of early antiviral immunity. Previous studies revealed that a single amino acid change (R312A) in VP35 renders the protein unable to inhibit IRF-3 activation. A reverse-genetics-generated, mouse-adapted, recombinant Ebola virus that encodes the R312A mutation in VP35 was produced. We found that relative to the case for wild-type virus containing the authentic VP35 sequence, this single amino acid change in VP35 renders the virus completely attenuated in mice. Given that these viruses differ by only a single amino acid in the IRF-3 inhibitory domain of VP35, the level of alteration of virulence is remarkable and highlights the importance of VP35 for the pathogenesis of Ebola virus.

  2. Mutational analysis of Kaposica reveals that bridging of MG2 and CUB domains of target protein is crucial for the cofactor activity of RCA proteins

    PubMed Central

    Gautam, Avneesh Kumar; Panse, Yogesh; Ghosh, Payel; Reza, Malik Johid; Mullick, Jayati; Sahu, Arvind

    2015-01-01

    The complement system has evolved to annul pathogens, but its improper regulation is linked with diseases. Efficient regulation of the system is primarily provided by a family of proteins termed regulators of complement activation (RCA). The knowledge of precise structural determinants of RCA proteins critical for imparting the regulatory activities and the molecular events underlying the regulatory processes, nonetheless, is still limited. Here, we have dissected the structural requirements of RCA proteins that are crucial for one of their two regulatory activities, the cofactor activity (CFA), by using the Kaposi’s sarcoma-associated herpesvirus RCA homolog Kaposica as a model protein. We have scanned the entire Kaposica molecule by sequential mutagenesis using swapping and site-directed mutagenesis, which identified residues critical for its interaction with C3b and factor I. Mapping of these residues onto the modeled structure of C3b–Kaposica–factor I complex supported the mutagenesis data. Furthermore, the model suggested that the C3b-interacting residues bridge the CUB (complement C1r-C1s, Uegf, Bmp1) and MG2 (macroglobulin-2) domains of C3b. Thus, it seems that stabilization of the CUB domain with respect to the core of the C3b molecule is central for its CFA. Identification of CFA-critical regions in Kaposica guided experiments in which the equivalent regions of membrane cofactor protein were swapped into decay-accelerating factor. This strategy allowed CFA to be introduced into decay-accelerating factor, suggesting that viral and human regulators use a common mechanism for CFA. PMID:26420870

  3. [Therapeutic restraint management in Intensive Care Units: Phenomenological approach to nursing reality].

    PubMed

    Acevedo-Nuevo, M; González-Gil, M T; Solís-Muñoz, M; Láiz-Díez, N; Toraño-Olivera, M J; Carrasco-Rodríguez-Rey, L F; García-González, S; Velasco-Sanz, T R; Martínez-Álvarez, A; Martin-Rivera, B E

    2016-01-01

    To identify nursing experience on physical restraint management in Critical Care Units. To analyse similarities and differences in nursing experience on physical restraint management according to the clinical context that they are involved in. A multicentre phenomenological study was carried out including 14 Critical Care Units in Madrid, classified according to physical restraint use: Common/systematic use, lacking/personalised use, and mixed use. Five focus groups (23 participants were selected following purposeful sampling) were convened, concluding in data saturation. Data analysis was focused on thematic content analysis following Colaizzi's method. Six main themes: Physical restraint meaning in Critical Care Units, safety (self-retreat vital devices), contribution factors, feelings, alternatives, and pending issues. Although some themes are common to the 3 Critical Care Unit types, discourse differences are found as regards to indication, feelings, systematic use of pain and sedation measurement tools. In order to achieve real physical restraint reduction in Critical Care Units, it is necessary to have a deep understanding of restraints use in the specific clinical context. As self-retreat vital devices emerge as central concept, some interventions proposed in other settings could not be effective, requiring alternatives for critical care patients. Discourse variations laid out in the different Critical Care Unit types could highlight key items that determine the use and different attitudes towards physical restraint. Copyright © 2015 Elsevier España, S.L.U. y SEEIUC. All rights reserved.

  4. Anaemia only causes a small reduction in the upper critical temperature of sea bass: is oxygen delivery the limiting factor for tolerance of acute warming in fishes?

    PubMed

    Wang, Tobias; Lefevre, Sjannie; Iversen, Nina K; Findorf, Inge; Buchanan, Rasmus; McKenzie, David J

    2014-12-15

    To address how the capacity for oxygen transport influences tolerance of acute warming in fishes, we investigated whether a reduction in haematocrit, by means of intra-peritoneal injection of the haemolytic agent phenylhydrazine, lowered the upper critical temperature of sea bass. A reduction in haematocrit from 42±2% to 20±3% (mean ± s.e.m.) caused a significant but minor reduction in upper critical temperature, from 35.8±0.1 to 35.1±0.2°C, with no correlation between individual values for haematocrit and upper thermal limit. Anaemia did not influence the rise in oxygen uptake between 25 and 33°C, because the anaemic fish were able to compensate for reduced blood oxygen carrying capacity with a significant increase in cardiac output. Therefore, in sea bass the upper critical temperature, at which they lost equilibrium, was not determined by an inability of the cardio-respiratory system to meet the thermal acceleration of metabolic demands. © 2014. Published by The Company of Biologists Ltd.

  5. A Cross-Industry Review of B2B Critical Success Factors.

    ERIC Educational Resources Information Center

    Eid, Riyad; Trueman, Myfanwy; Ahmed, Abdel Moneim

    2002-01-01

    Presents a comprehensive review of B2B (business-to- business) international Internet marketing and identifies 21 critical success factors in five categories: marketing strategy, including management support, strategic goals, and collaboration; Web site factors, including Web site design; global factors, including multilanguage sites and cultural…

  6. Critical desertification transition in semi-arid ecosystems: The role of local facilitation and colonization rate

    NASA Astrophysics Data System (ADS)

    Corrado, Raffaele; Cherubini, Anna Maria; Pennetta, Cecilia

    2015-05-01

    In this work we study the effect of two different ecological mechanisms on the desertification transition in arid or semi-arid ecosystems, modeled by a stochastic cellular automaton. Namely we consider the role of the facilitation mechanism, i.e. the local positive effects of plants on their neighborhood and of colonization factors, such as seed production, survival and germination probabilities. Within the model, the strength of these two mechanisms is determined by the parameters f and b, respectively controlling the rates of the recovery and colonization processes. In particular we focus on the full desertification transition occurring at increasing value of the mortality rate m and we discuss how the values of f and b affect the critical mortality mc , the critical exponents β and γσ‧, determining the power-law scaling of the average vegetation density and of the root-mean-square deviation of the density fluctuations, and the character of the transition: continuous or abrupt. We show that mc strongly depends on both f and b, a dependence which accounts for the higher resilience of the ecosystems to external stresses as a consequence of an increased effectiveness of positive feedback effects. On the other hand, concerning the value of the exponents and the character of the transition, our results point out that both these features are unaffected by changes in the strength of the local facilitation. Viceversa, we show that an increase of the colonization factor b significantly modifies the values of the exponents and the order of the transition, changing a continuous transition into an abrupt one. We explain these results in terms of the different range of the interactions characterizing facilitation and colonization mechanisms.

  7. Effect of Metamorphic Foliation on Regolith Thickness, Catalina Critical Zone Observatory, Arizona

    NASA Astrophysics Data System (ADS)

    Leone, J. D.; Holbrook, W. S.; Chorover, J.; Carr, B.

    2016-12-01

    Terrestrial life is sustained by nutrients and water held in soil and weathered rock, which are components of the Earth's critical zone, referred to as regolith. The thickness of regolith in the near-surface is thought to be influenced by factors such as climate, topographic stress, erosion and lithology. Our study has two aims: to determine the effect of metamorphic foliation on regolith thickness and to test an environmental model, Effective Energy Mass Transfer (EEMT), within a zero-order basin (ZOB) in the Santa Catalina Mountains. Seismic refraction and electrical resistivity data show a stark contrast in physical properties, and inferred regolith thickness, on north- versus south-facing slopes: north-facing slopes are characterized by higher seismic velocities and higher resistivities, consistent with thin regolith, while south-facing slopes show lower resistivities and velocities, indicative of deeper and more extensive weathering. This contrast is exactly the opposite of that expected from most climatic models, including the EEMT model, which predicts deeper regolith on north-facing slopes. Instead, regolith thickness appears to be controlled by metamorphic foliation: we observed a general, positive correlation between interpreted regolith thickness and foliation dip within heavily foliated lithologies and no correlation in weakly foliated lithologies. We hypothesize that hydraulic conductivity controls weathering here: where foliation is parallel to the surface topography, regolith is thin, but where foliation pierces the surface topography at a substantial angle, regolith is thick. The effect of foliation is much larger than that expected from environmental models: regolith thickness varies by a factor of 4 (2.5 m vs. 10 m). These results suggest that metamorphic foliation, and perhaps by extension sedimentary layering, plays a key role in determining regolith thickness and must be accounted for in models of critical zone development.

  8. Utilizing an Energy Management System with Distributed Resources to Manage Critical Loads and Reduce Energy Costs

    DTIC Science & Technology

    2014-09-01

    peak shaving, conducting power factor correction, matching critical load to most efficient distributed resource, and islanding a system during...photovoltaic arrays during islanding, and power factor correction, the implementation of the ESS by itself is likely to prove cost prohibitive. The DOD...These functions include peak shaving, conducting power factor correction, matching critical load to most efficient distributed resource, and islanding a

  9. Healthcare Disparities in Critical Illness

    PubMed Central

    Soto, Graciela J.; Martin, Greg S.; Gong, Michelle Ng

    2013-01-01

    Objective To summarize the current literature on racial and gender disparities in critical care and the mechanisms underlying these disparities in the course of acute critical illness. Data Sources MEDLINE search on the published literature addressing racial, ethnic, or gender disparities in acute critical illness such as sepsis, acute lung injury, pneumonia, venous thromboembolism, and cardiac arrest. Study Selection Clinical studies that evaluated general critically ill patient populations in the United States as well as specific critical care conditions were reviewed with a focus on studies evaluating factors and contributors to health disparities. Data Extraction Study findings are presented according to their association with the incidence, clinical presentation, management, and outcomes in acute critical illness. Data Synthesis This review presents potential contributors for racial and gender disparities related to genetic susceptibility, comorbidities, preventive health services, socioeconomic factors, cultural differences, and access to care. The data is organized along the course of acute critical illness. Conclusions The literature to date shows that disparities in critical care are most likely multifactorial involving individual, community, and hospital-level factors at several points in the continuum of acute critical illness. The data presented identify potential targets as interventions to reduce disparities in critical care and future avenues for research. PMID:24121467

  10. Healthcare disparities in critical illness.

    PubMed

    Soto, Graciela J; Martin, Greg S; Gong, Michelle Ng

    2013-12-01

    To summarize the current literature on racial and gender disparities in critical care and the mechanisms underlying these disparities in the course of acute critical illness. MEDLINE search on the published literature addressing racial, ethnic, or gender disparities in acute critical illness, such as sepsis, acute lung injury, pneumonia, venous thromboembolism, and cardiac arrest. Clinical studies that evaluated general critically ill patient populations in the United States as well as specific critical care conditions were reviewed with a focus on studies evaluating factors and contributors to health disparities. Study findings are presented according to their association with the prevalence, clinical presentation, management, and outcomes in acute critical illness. This review presents potential contributors for racial and gender disparities related to genetic susceptibility, comorbidities, preventive health services, socioeconomic factors, cultural differences, and access to care. The data are organized along the course of acute critical illness. The literature to date shows that disparities in critical care are most likely multifactorial involving individual, community, and hospital-level factors at several points in the continuum of acute critical illness. The data presented identify potential targets as interventions to reduce disparities in critical care and future avenues for research.

  11. Game Indicators Determining Sports Performance in the NBA

    PubMed Central

    Mikołajec, Kazimierz; Maszczyk, Adam; Zając, Tomasz

    The main goal of the present study was to identify basketball game performance indicators which best determine sports level in the National Basketball Association (NBA) league. The research material consisted of all NBA game statistics at the turn of eight seasons (2003–11) and included 52 performance variables. Through detailed analysis the variables with high influence on game effectiveness were selected for final procedures. It has been proven that a limited number of factors, mostly offensive, determines sports performance in the NBA. The most critical indicators are: Win%, Offensive EFF, 3rd Quarter PPG, Win% CG, Avg Fauls and Avg Steals. In practical applications these results connected with top teams and elite players may help coaches to design better training programs. PMID:24146715

  12. Game Indicators Determining Sports Performance in the NBA.

    PubMed

    Mikołajec, Kazimierz; Maszczyk, Adam; Zając, Tomasz

    2013-01-01

    The main goal of the present study was to identify basketball game performance indicators which best determine sports level in the National Basketball Association (NBA) league. The research material consisted of all NBA game statistics at the turn of eight seasons (2003-11) and included 52 performance variables. Through detailed analysis the variables with high influence on game effectiveness were selected for final procedures. It has been proven that a limited number of factors, mostly offensive, determines sports performance in the NBA. The most critical indicators are: Win%, Offensive EFF, 3rd Quarter PPG, Win% CG, Avg Fauls and Avg Steals. In practical applications these results connected with top teams and elite players may help coaches to design better training programs.

  13. Designing Web-based GIS Application by CSF Method: A Case Study in Boven Digoel Papua

    NASA Astrophysics Data System (ADS)

    Letsoin, Hendrykus Saritangdan; JSantoso, Albertus Joko; Suyoto

    2018-02-01

    Since Boven Digoel Regency was established in 2003, to this day its infrastructures are very limited, the region is still not developed, Human Resources (SDM) and Information and Communication Technology are still manual. The development of Geographic Information System was expected to contribute to ICT development in Papua, particularly Boven Digoel Regency, in displaying data of existing local potentials, e.g. tourism, plantation and forestry. Critical Success Factor Method was the right method in considering factors determining the success of the implementation of a strategy, in good information management and in providing data of local potentials of geographic information system for people in Boven Digoel Regency and the people of Indonesia in general to introduce Boven Digoel Regency, Papua. Framework Laravel with PHP programming language was expected to support Geographic Information System well to determine the distribution of local potentials in Boven Digoel Regency‥

  14. Restrictive vs. non-restrictive composition: a magnetoencephalography study

    PubMed Central

    Leffel, Timothy; Lauter, Miriam; Westerlund, Masha; Pylkkänen, Liina

    2014-01-01

    Recent research on the brain mechanisms underlying language processing has implicated the left anterior temporal lobe (LATL) as a central region for the composition of simple phrases. Because these studies typically present their critical stimuli without contextual information, the sensitivity of LATL responses to contextual factors is unknown. In this magnetoencephalography (MEG) study, we employed a simple question-answer paradigm to manipulate whether a prenominal adjective or determiner is interpreted restrictively, i.e., as limiting the set of entities under discussion. Our results show that the LATL is sensitive to restriction, with restrictive composition eliciting higher responses than non-restrictive composition. However, this effect was only observed when the restricting element was a determiner, adjectival stimuli showing the opposite pattern, which we hypothesise to be driven by the special pragmatic properties of non-restrictive adjectives. Overall, our results demonstrate a robust sensitivity of the LATL to high level contextual and potentially also pragmatic factors. PMID:25379512

  15. Analysis of starvation effects on hydrodynamic lubrication in nonconforming contacts

    NASA Technical Reports Server (NTRS)

    Brewe, D. E.; Hamrock, B. J.

    1981-01-01

    Numerical methods were used to determine the effects of lubricant starvation on the minimum film thickness under conditions of a hydrodynamic point contact. Starvation was effected by varying the fluid inlet level. The Reynolds boundary conditions were applied at the cavitation boundary and zero pressure was stipulated at the meniscus or inlet boundary. A minimum-fill-thickness equation as a function of both the ratio of dimensionless load to dimensionless speed and inlet supply level was determined. By comparing the film generated under the starved inlet condition with the film generated from the fully flooded inlet, an expression for the film reduction factor was obtained. Based on this factor a starvation threshold was defined as well as a critically starved inlet. The changes in the inlet pressure buildup due to changing the available lubricant supply are presented in the form of three dimensional isometric plots and also in the form of contour plots.

  16. Geometry and starvation effects in hydrodynamic lubrication

    NASA Technical Reports Server (NTRS)

    Brewe, D. E.; Hamrock, B. J.

    1982-01-01

    Numerical methods were used to determine the effects of lubricant starvation on the minimum film thickness under conditions of a hydrodynamic point contact. Starvation was effected by varying the fluid inlet level. The Reynolds boundary conditions were applied at the cavitation boundary and zero pressure was stipulated at the meniscus or inlet boundary. A minimum-film-thickness equation as a function of both the ratio of dimensionless load to dimensionless speed and inlet supply level was determined. By comparing the film generated under the starved inlet condition with the film generated from the fully flooded inlet, an expression for the film reduction factor was obtained. Based on this factor a starvation threshold was defined as well as a critically starved inlet. The changes in the inlet pressure buildup due to changing the available lubricant supply are presented in the form of three dimensional isometric plots and also in the form of contour plots.

  17. Immunity in a variable world

    PubMed Central

    Lazzaro, Brian P.; Little, Tom J.

    2008-01-01

    Immune function is likely to be a critical determinant of an organism's fitness, yet most natural animal and plant populations exhibit tremendous genetic variation for immune traits. Accumulating evidence suggests that environmental heterogeneity may retard the long-term efficiency of natural selection and even maintain polymorphism, provided alternative host genotypes are favoured under different environmental conditions. ‘Environment’ in this context refers to abiotic factors such as ambient temperature or availability of nutrient resources, genetic diversity of pathogens or competing physiological demands on the host. These factors are generally controlled in laboratory experiments measuring immune performance, but variation in them is likely to be very important in the evolution of resistance to infection. Here, we review some of the literature emphasizing the complexity of natural selection on immunity. Our aim is to describe how environmental and genetic heterogeneities, often excluded from experimentation as ‘noise’, may determine the evolutionary potential of populations or the potential for interacting species to coevolve. PMID:18926975

  18. Present and future of membrane protein structure determination by electron crystallography.

    PubMed

    Ubarretxena-Belandia, Iban; Stokes, David L

    2010-01-01

    Membrane proteins are critical to cell physiology, playing roles in signaling, trafficking, transport, adhesion, and recognition. Despite their relative abundance in the proteome and their prevalence as targets of therapeutic drugs, structural information about membrane proteins is in short supply. This chapter describes the use of electron crystallography as a tool for determining membrane protein structures. Electron crystallography offers distinct advantages relative to the alternatives of X-ray crystallography and NMR spectroscopy. Namely, membrane proteins are placed in their native membranous environment, which is likely to favor a native conformation and allow changes in conformation in response to physiological ligands. Nevertheless, there are significant logistical challenges in finding appropriate conditions for inducing membrane proteins to form two-dimensional arrays within the membrane and in using electron cryo-microscopy to collect the data required for structure determination. A number of developments are described for high-throughput screening of crystallization trials and for automated imaging of crystals with the electron microscope. These tools are critical for exploring the necessary range of factors governing the crystallization process. There have also been recent software developments to facilitate the process of structure determination. However, further innovations in the algorithms used for processing images and electron diffraction are necessary to improve throughput and to make electron crystallography truly viable as a method for determining atomic structures of membrane proteins. Copyright © 2010 Elsevier Inc. All rights reserved.

  19. Present and future of membrane protein structure determination by electron crystallography

    PubMed Central

    Ubarretxena-Belandia, Iban; Stokes, David L.

    2011-01-01

    Membrane proteins are critical to cell physiology, playing roles in signaling, trafficking, transport, adhesion, and recognition. Despite their relative abundance in the proteome and their prevalence as targets of therapeutic drugs, structural information about membrane proteins is in short supply. This review describes the use of electron crystallography as a tool for determining membrane protein structures. Electron crystallography offers distinct advantages relative to the alternatives of X-ray crystallography and NMR spectroscopy. Namely, membrane proteins are placed in their native membranous environment, which is likely to favor a native conformation and allow changes in conformation in response to physiological ligands. Nevertheless, there are significant logistical challenges in finding appropriate conditions for inducing membrane proteins to form two-dimensional arrays within the membrane and in using electron cryo-microscopy to collect the data required for structure determination. A number of developments are described for high-throughput screening of crystallization trials and for automated imaging of crystals with the electron microscope. These tools are critical for exploring the necessary range of factors governing the crystallization process. There have also been recent software developments to facilitate the process of structure determination. However, further innovations in the algorithms used for processing images and electron diffraction are necessary to improve throughput and to make electron crystallography truly viable as a method for determining atomic structures of membrane proteins. PMID:21115172

  20. Critical micelle concentration values for different surfactants measured with solid-phase microextraction fibers.

    PubMed

    Haftka, Joris J-H; Scherpenisse, Peter; Oetter, Günter; Hodges, Geoff; Eadsforth, Charles V; Kotthoff, Matthias; Hermens, Joop L M

    2016-09-01

    The amphiphilic nature of surfactants drives the formation of micelles at the critical micelle concentration (CMC). Solid-phase microextraction (SPME) fibers were used in the present study to measure CMC values of 12 nonionic, anionic, cationic, and zwitterionic surfactants. The SPME-derived CMC values were compared to values determined using a traditional surface tension method. At the CMC of a surfactant, a break in the relationship between the concentration in SPME fibers and the concentration in water is observed. The CMC values determined with SPME fibers deviated by less than a factor of 3 from values determined with a surface tension method for 7 out of 12 compounds. In addition, the fiber-water sorption isotherms gave information about the sorption mechanism to polyacrylate-coated SPME fibers. A limitation of the SPME method is that CMCs for very hydrophobic cationic surfactants cannot be determined when the cation exchange capacity of the SPME fibers is lower than the CMC value. The advantage of the SPME method over other methods is that CMC values of individual compounds in a mixture can be determined with this method. However, CMC values may be affected by the presence of compounds with other chain lengths in the mixture because of possible mixed micelle formation. Environ Toxicol Chem 2016;35:2173-2181. © 2016 SETAC. © 2016 SETAC.

  1. Critical Components of Curriculum Development for Career and Technical Education Instructors in the United States

    ERIC Educational Resources Information Center

    Wang, Victor C. X.

    2010-01-01

    Developing curriculum(s) requires instructors to take into several factors. These factors can be viewed as critical components of curriculum development for career and technical education (CTE) instructors. Without adequately addressing critical components such as curriculum history, curriculum theory, curriculum philosophies, curriculum…

  2. The 1983 Beirut Airport terrorist bombing. Injury patterns and implications for disaster management.

    PubMed

    Frykberg, E R; Tepas, J J; Alexander, R H

    1989-03-01

    The casualty profile and results of the medical care provided for the survivors of the terrorist truck bombing of the U.S. Marine Corps facility in Beirut, Lebanon, in 1983 were reviewed to determine the factors that influenced casualty survival. This explosion resulted in 346 casualties, of whom 234 (68%) were immediately killed. The spectrum of injury was determined in 85 survivors using the Injury Severity Score (ISS). There were seven (6.3%) deaths among the 112 immediate survivors. All deaths occurred among the 19 (17%) victims who were critically injured (ISS greater than 15), giving a mortality in this population of 37 per cent. Six (86%) of the seven deaths were associated with an initial delay in treatment. Head injury was the most common fatal injury among both immediate fatalities (71.4%) and immediate survivors (57%). Thoracic injury and burns each accounted for 29 per cent of survivor deaths. Triage efficiency, as determined by the rates of overtriage (80%) and undertriage (0), did not appear adversely to affect mortality. Critical analysis of disasters such as this can contribute to improvements in preparation and casualty care in the event of future disasters.

  3. Critical Success Factors for E-Learning Acceptance: Confirmatory Factor Models

    ERIC Educational Resources Information Center

    Selim, Hassan M.

    2007-01-01

    E-learning, one of the tools emerged from information technology, has been integrated in many university programs. There are several factors that need to be considered while developing or implementing university curriculums that offer e-learning based courses. This paper is intended to specify e-learning critical success factors (CSFs) as…

  4. Kuipers conducts ARGES experiment OPS at the MSG during EXP 8 / EXP 9

    NASA Image and Video Library

    2004-04-24

    ISS008-E-22128 (24 April 2004) --- European Space Agency (ESA) astronaut Andre Kuipers of the Netherlands works with the ARGES experiment for the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station (ISS). The main objectives of ARGES are to determine which factors are critical in the onset of instabilities in High-Intensity Discharge (HID) lamps and to characterize the separation of individual gaseous elements inside.

  5. Labor Needs to Adjust Compensation Benefits It Pays Injured Federal Employees to Levels Appropriate to Their Disabilities.

    DTIC Science & Technology

    1984-03-26

    with little j likelihood of criticism from the claimant. Taken together, p. these factors tend to give examiners little motivation to estab- lish wage...claims examiners are expected to place a high priority on these tasks. Similar motivation does not exist for wage earning capacity determinations. Low 4...8217- pS4 -% ..:4.: .,.,, O :,% ’’- ,’ , , ;" , ’:",,’,i k. ’, ’, , ’ .vv

  6. Functional Task Test (FTT)

    NASA Technical Reports Server (NTRS)

    Bloomberg, Jacob J.; Mulavara, Ajitkumar; Peters, Brian T.; Rescheke, Millard F.; Wood, Scott; Lawrence, Emily; Koffman, Igor; Ploutz-Snyder, Lori; Spiering, Barry A.; Feeback, Daniel L.; hide

    2009-01-01

    This slide presentation reviews the Functional Task Test (FTT), an interdisciplinary testing regimen that has been developed to evaluate astronaut postflight functional performance and related physiological changes. The objectives of the project are: (1) to develop a set of functional tasks that represent critical mission tasks for the Constellation Program, (2) determine the ability to perform these tasks after space flight, (3) Identify the key physiological factors that contribute to functional decrements and (4) Use this information to develop targeted countermeasures.

  7. Antiwear Additive Mechanisms in Sliding Contacts

    NASA Technical Reports Server (NTRS)

    Baldwin, B. A.

    1984-01-01

    The possible mechanisms associated with wear in a sliding contact and how an oil and antiwear additive can mitigate wear or prevent catastropic seizure of the contacting parts was examined. The various load and temperature regimes are examined and the mechanisms which are predominant under these conditions are determined. The critical mechanism(s) depend on the test parameters, particularly load and temperature, although sliding speed is also a factor. Different ways to improve the efficiency of antiwear additives are suggested.

  8. Determination of Critical Parameters Based on the Intensity of Transmitted Light Around Gas-Liquid Interface: Critical Parameters of CO

    NASA Astrophysics Data System (ADS)

    Nakayama, Masaki; Katano, Hiroaki; Sato, Haruki

    2014-05-01

    A precise determination of the critical temperature and density for technically important fluids would be possible on the basis of the digital image for the visual observation of the phase boundary in the vicinity of the critical point since the sensitivity and resolution are higher than those of naked eyes. In addition, the digital image can avoid the personal uncertainty of an observer. A strong density gradient occurs in a sample cell at the critical point due to gravity. It was carefully assessed to determine the critical density, where the density profile in the sample cell can be observed from the luminance profile of a digital image. The density-gradient profile becomes symmetric at the critical point. One of the best fluids, whose thermodynamic properties have been measured with the highest reliability among technically important fluids, would be carbon dioxide. In order to confirm the reliability of the proposed method, the critical temperature and density of carbon dioxide were determined using the digital image. The critical temperature and density values of carbon dioxide are ( and ( kg m, respectively. The critical temperature and density values agree with the existing best values within estimated uncertainties. The reliability of the method was confirmed. The critical pressure, 7.3795 MPa, corresponding to the determined critical temperature of 304.143 K is also proposed. A new set of parameters for the vapor-pressure equation is also provided.

  9. Lean principles and defense information technology acquisition: An investigation of the determinants of successful application

    NASA Astrophysics Data System (ADS)

    Haley, M.

    The purpose of this study was to investigate whether or not there have been successful applications of lean manufacturing principles in highly variable defense IT environments. Specifically, the study assessed if implementation of the lean philosophies by a defense organization yielded repeatable, predictable results in software release schedules reductions. Additionally, the study set out to determine what potential critical success factors (CSF's) were documented in the secondary data captured for each release, and extracted the variables used in the decision making for acceptability of fielding. In evaluating lean applicability to the high variability environment of USAF IT acquisitions, the research was conducted using non-experimental quantitative methods of archival secondary data. The sample for this case study was compiled from a USAF office that had implemented these techniques in pre-development, development and testing, and fielding phases. Based on the research data, acquisitionists and lean practitioners are inherently interconnected. Therefore, an understanding that critical success factors (CSFs) are integral to successful lean application in DoD IT acquisitions is crucial. Through a combination of synergistic alignments, plyometric CSFs were discovered to maximize the effects of each single CSF to produce rapid results in defense IT acquisitions. These include: (1) Enterprise Incorporation, (2) Team Trust, (3) Transformational Leadership, (4) Recursive Improvement, (5) Integrated Synergy, (6) Customer-Centric Culture and (7) Heuristic Communication.

  10. Size-dependent response of foraminiferal calcification to seawater carbonate chemistry

    NASA Astrophysics Data System (ADS)

    Henehan, Michael J.; Evans, David; Shankle, Madison; Burke, Janet E.; Foster, Gavin L.; Anagnostou, Eleni; Chalk, Thomas B.; Stewart, Joseph A.; Alt, Claudia H. S.; Durrant, Joseph; Hull, Pincelli M.

    2017-07-01

    The response of the marine carbon cycle to changes in atmospheric CO2 concentrations will be determined, in part, by the relative response of calcifying and non-calcifying organisms to global change. Planktonic foraminifera are responsible for a quarter or more of global carbonate production, therefore understanding the sensitivity of calcification in these organisms to environmental change is critical. Despite this, there remains little consensus as to whether, or to what extent, chemical and physical factors affect foraminiferal calcification. To address this, we directly test the effect of multiple controls on calcification in culture experiments and core-top measurements of Globigerinoides ruber. We find that two factors, body size and the carbonate system, strongly influence calcification intensity in life, but that exposure to corrosive bottom waters can overprint this signal post mortem. Using a simple model for the addition of calcite through ontogeny, we show that variable body size between and within datasets could complicate studies that examine environmental controls on foraminiferal shell weight. In addition, we suggest that size could ultimately play a role in determining whether calcification will increase or decrease with acidification. Our models highlight that knowledge of the specific morphological and physiological mechanisms driving ontogenetic change in calcification in different species will be critical in predicting the response of foraminiferal calcification to future change in atmospheric pCO2.

  11. Surveying the meritocracy: the problems of intelligence and mobility in the studies of the Population Investigation Committee.

    PubMed

    Ramsden, Edmund

    2014-09-01

    The post-war era saw the emergence of large-scale and longitudinal social and medical surveys in Britain. That these surveys were both representative of an entire nation and could follow individuals throughout their lives, gave them a privileged position in relation to policy-making. This paper will focus on two closely interrelated surveys, both instigated by the Population Investigation Committee at London School of Economics-the National Survey of Health and Development, which began in 1946, and the Scottish Mental Survey of 1947. These surveys had a critical role in educational research and policy and, more specifically, in changing perspectives regarding the concept and measurement of intelligence. They were seen to privilege social and environmental factors as determinants of mental ability, and they shifted attention away from genetic factors and eugenic concerns. However, while the surveys were indeed powerful tools, their structure, the questions they asked, the methods they used and the choices made over the data to be tabulated, also determined what could be known. The paper will examine the growing criticism and debate over the large-scale survey. Many argued that smaller-scale studies were more effective in understanding the social and biological causes of intellectual differences, and better for identifying the benefits and dangers of using intelligence and merit as a means of organising society. Copyright © 2014. Published by Elsevier Ltd.

  12. The fetal origins of adult disease: a narrative review of the epidemiological literature

    PubMed Central

    Skogen, Jens Christoffer; Øverland, Simon

    2012-01-01

    The fetal origins of adult disease (FOAD) hypothesis suggests that risk factors from intrauterine environmental exposures affect the fetus' development during sensitive periods, and increases the risk of specific diseases in adult life. This link was initially observed between prenatal exposures and adult coronary heart disease, but corresponding observations have later been published for a range of chronic conditions. Although the hypothesis has been praised as an essential shift in our understanding of determinants for health, the hypothesis has also been criticized on a number of accounts, both methodologically and theoretically. The aim of this paper is to critically discuss the FOAD-hypothesis, in relation to the epidemiological evidence. We conclude that much of the research literature on the FOAD-hypothesis finds support for the hypothesis. Despite this, it is still unclear if the effects are independent and what the public health relevance is. Notwithstanding the heart of the hypothesis – that environmental influences during gestation have an effect on later development – should be considered a major insight and constitutes a complement to a focus on genetic and more proximal factors (such as adult lifestyle) as causes of adult disease. As the search for determinants for disease and health continues, the FOAD-hypothesis is likely to remain an important perspective. It may however be better positioned as part of a broader life course perspective, rather than as an independent hypothesis. PMID:23301147

  13. Zooming in and out: Scale dependence of extrinsic and intrinsic factors affecting salt marsh erosion

    NASA Astrophysics Data System (ADS)

    Wang, Heng; van der Wal, Daphne; Li, Xiangyu; van Belzen, Jim; Herman, Peter M. J.; Hu, Zhan; Ge, Zhenming; Zhang, Liquan; Bouma, Tjeerd J.

    2017-07-01

    Salt marshes are valuable ecosystems that provide important ecosystem services. Given the global scale of marsh loss due to climate change and coastal squeeze, there is a pressing need to identify the critical extrinsic (wind exposure and foreshore morphology) and intrinsic factors (soil and vegetation properties) affecting the erosion of salt marsh edges. In this study, we quantified rates of cliff lateral retreat (i.e., the eroding edge of a salt marsh plateau) using a time series of aerial photographs taken over four salt marsh sites in the Westerschelde estuary, the Netherlands. In addition, we experimentally quantified the erodibility of sediment cores collected from the marsh edge of these four marshes using wave tanks. Our results revealed the following: (i) at the large scale, wind exposure and the presence of pioneer vegetation in front of the cliff were the key factors governing cliff retreat rates; (ii) at the intermediate scale, foreshore morphology was partially related to cliff retreat; (iii) at the local scale, the erodibility of the sediment itself at the marsh edge played a large role in determining the cliff retreat rate; and (iv) at the mesocosm scale, cliff erodibility was determined by soil properties and belowground root biomass. Thus, both extrinsic and intrinsic factors determined the fate of the salt marsh but at different scales. Our study highlights the importance of understanding the scale dependence of the factors driving the evolution of salt marsh landscapes.

  14. Impact of measurement uncertainty from experimental load distribution factors on bridge load rating

    NASA Astrophysics Data System (ADS)

    Gangone, Michael V.; Whelan, Matthew J.

    2018-03-01

    Load rating and testing of highway bridges is important in determining the capacity of the structure. Experimental load rating utilizes strain transducers placed at critical locations of the superstructure to measure normal strains. These strains are then used in computing diagnostic performance measures (neutral axis of bending, load distribution factor) and ultimately a load rating. However, it has been shown that experimentally obtained strain measurements contain uncertainties associated with the accuracy and precision of the sensor and sensing system. These uncertainties propagate through to the diagnostic indicators that in turn transmit into the load rating calculation. This paper will analyze the effect that measurement uncertainties have on the experimental load rating results of a 3 span multi-girder/stringer steel and concrete bridge. The focus of this paper will be limited to the uncertainty associated with the experimental distribution factor estimate. For the testing discussed, strain readings were gathered at the midspan of each span of both exterior girders and the center girder. Test vehicles of known weight were positioned at specified locations on each span to generate maximum strain response for each of the five girders. The strain uncertainties were used in conjunction with a propagation formula developed by the authors to determine the standard uncertainty in the distribution factor estimates. This distribution factor uncertainty is then introduced into the load rating computation to determine the possible range of the load rating. The results show the importance of understanding measurement uncertainty in experimental load testing.

  15. Risk Factors, Pathobiomechanics and Physical Examination of Rotator Cuff Tears

    PubMed Central

    Moulton, Samuel G.; Greenspoon, Joshua A.; Millett, Peter J.; Petri, Maximilian

    2016-01-01

    Background: It is important to appreciate the risk factors for the development of rotator cuff tears and specific physical examination maneuvers. Methods: A selective literature search was performed. Results: Numerous well-designed studies have demonstrated that common risk factors include age, occupation, and anatomic considerations such as the critical shoulder angle. Recently, research has also reported a genetic component as well. The rotator cuff axially compresses the humeral head in the glenohumeral joint and provides rotational motion and abduction. Forces are grouped into coronal and axial force couples. Rotator cuff tears are thought to occur when the force couples become imbalanced. Conclusion: Physical examination is essential to determining whether a patient has an anterosuperior or posterosuperior tear. Diagnostic accuracy increases when combining a series of examination maneuvers. PMID:27708731

  16. Critical thinking competence and disposition of clinical nurses in a medical center.

    PubMed

    Feng, Rung-Chuang; Chen, Mei-Jung; Chen, Mei-Chuan; Pai, Yu-Chu

    2010-06-01

    Critical thinking is essential in nursing practice. Promoting critical thinking competence in clinical nurses is an important way to improve problem solving and decision-making competence to further improve the quality of patient care. However, using an adequate tool to test nurses' critical thinking competence and disposition may provide the reference criteria for clinical nurse characterization, training planning, and resource allocation for human resource management. The purpose of this study was to measure the critical thinking competence and critical thinking disposition of clinical nurses as well as to explore the related factors of critical thinking competence. Clinical nurses from four different clinical ladders selected from one medical center were stratified randomly. All qualified subjects who submitted valid questionnaires were included in the study. A Taiwan version of the modified Watson-Glaser Critical Thinking Appraisal and Critical Thinking Disposition Inventory was developed to measure the critical thinking competence and critical thinking disposition of clinical nurses. Validity was evaluated using the professional content test (content validity index = .93). Reliability was assessed with a Cronbach's alpha coefficient of .85. Data were analyzed using the SPSS for Windows (Version 12.0; SPSS Inc., Chicago, IL). Results showed that competence of interpretation was the highest critical thinking competence factor. Inference was the lowest, and reflective thinking as a critical thinking disposition was more positive. In addition, age, years of nursing experience, and experiences in other hospitals significantly influenced critical thinking competence (p < .05). Factors of age, years of experience, and nurses clinical ladder were shown to affect critical thinking disposition scores. Clinical ladder N4 nurses had the highest scores in both competence and disposition. A significant relationship was found between critical thinking competence and disposition scores, with 29.3% of the variance in critical thinking competence potentially explained by total years of nurse hospital experience. Clinical ladder and age were predictive factors for critical thinking disposition. Commonality was 27.9%. Nursing experience and clinical ladders positively affect critical thinking competence and disposition. Issues of critical thinking competence increasingly need to be measured. Therefore, appropriate tools for nursing professions should be further developed and explored for specific areas of practice.

  17. Characterization and optimization of cell seeding in scaffolds by factorial design: quality by design approach for skeletal tissue engineering.

    PubMed

    Chen, Yantian; Bloemen, Veerle; Impens, Saartje; Moesen, Maarten; Luyten, Frank P; Schrooten, Jan

    2011-12-01

    Cell seeding into scaffolds plays a crucial role in the development of efficient bone tissue engineering constructs. Hence, it becomes imperative to identify the key factors that quantitatively predict reproducible and efficient seeding protocols. In this study, the optimization of a cell seeding process was investigated using design of experiments (DOE) statistical methods. Five seeding factors (cell type, scaffold type, seeding volume, seeding density, and seeding time) were selected and investigated by means of two response parameters, critically related to the cell seeding process: cell seeding efficiency (CSE) and cell-specific viability (CSV). In addition, cell spatial distribution (CSD) was analyzed by Live/Dead staining assays. Analysis identified a number of statistically significant main factor effects and interactions. Among the five seeding factors, only seeding volume and seeding time significantly affected CSE and CSV. Also, cell and scaffold type were involved in the interactions with other seeding factors. Within the investigated ranges, optimal conditions in terms of CSV and CSD were obtained when seeding cells in a regular scaffold with an excess of medium. The results of this case study contribute to a better understanding and definition of optimal process parameters for cell seeding. A DOE strategy can identify and optimize critical process variables to reduce the variability and assists in determining which variables should be carefully controlled during good manufacturing practice production to enable a clinically relevant implant.

  18. The yeast Hot1 transcription factor is critical for activating a single target gene, STL1

    PubMed Central

    Bai, Chen; Tesker, Masha; Engelberg, David

    2015-01-01

    Transcription factors are commonly activated by signal transduction cascades and induce expression of many genes. They therefore play critical roles in determining the cell's fate. The yeast Hog1 MAP kinase pathway is believed to control the transcription of hundreds of genes via several transcription factors. To identify the bona fide target genes of Hog1, we inducibly expressed the spontaneously active variant Hog1D170A+F318L in cells lacking the Hog1 activator Pbs2. This system allowed monitoring the effects of Hog1 by itself. Expression of Hog1D170A+F318L in pbs2∆ cells imposed induction of just 105 and suppression of only 26 transcripts by at least twofold. We looked for the Hog1-responsive element within the promoter of the most highly induced gene, STL1 (88-fold). A novel Hog1 responsive element (HoRE) was identified and shown to be the direct target of the transcription factor Hot1. Unexpectedly, we could not find this HoRE in any other yeast promoter. In addition, the only gene whose expression was abolished in hot1∆ cells was STL1. Thus Hot1 is essential for transcription of just one gene, STL1. Hot1 may represent a class of transcription factors that are essential for transcription of a very few genes or even just one. PMID:25904326

  19. A case study evaluation of a Critical Care Information System adoption using the socio-technical and fit approach.

    PubMed

    Yusof, Maryati Mohd

    2015-07-01

    Clinical information systems have long been used in intensive care units but reports on their adoption and benefits are limited. This study evaluated a Critical Care Information System implementation. A case study summative evaluation was conducted, employing observation, interview, and document analysis in operating theatres and 16-bed adult intensive care units in a 400-bed Malaysian tertiary referral centre from the perspectives of users (nurses and physicians), management, and information technology staff. System implementation, factors influencing adoption, fit between these factors, and the impact of the Critical Care Information System were evaluated after eight months of operation. Positive influences on system adoption were associated with technical factors, including system ease of use, usefulness, and information relevancy; human factors, particularly user attitude; and organisational factors, namely clinical process-technology alignment and champions. Organisational factors such as planning, project management, training, technology support, turnover rate, clinical workload, and communication were barriers to system implementation and use. Recommendations to improve the current system problems were discussed. Most nursing staff positively perceived the system's reduction of documentation and data access time, giving them more time with patients. System acceptance varied among doctors. System use also had positive impacts on timesaving, data quality, and clinical workflow. Critical Care Information Systems is crucial and has great potentials in enhancing and delivering critical care. However, the case study findings showed that the system faced complex challenges and was underutilised despite its potential. The role of socio-technical factors and their fit in realizing the potential of Critical Care Information Systems requires continuous, in-depth evaluation and stakeholder understanding and acknowledgement. The comprehensive and specific evaluation measures of the Human-Organisation-Technology Fit framework can flexibly evaluate Critical Care Information Systems. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. A proposed cell model for multiple-occurrence regional landslide events: Implications for landslide susceptibility mapping

    NASA Astrophysics Data System (ADS)

    Crozier, M. J.

    2017-10-01

    Multiple-occurrence regional landslide events (MORLEs) consist of hundreds to thousands of shallow landslides occurring more or less simultaneously within defined areas, ranging from tens to thousands of square kilometres. While MORLEs can be triggered by rainstorms and earthquakes, this paper is confined to those landslide events triggered by rainstorms. Globally, MORLEs occur in a range of geological settings in areas of moderate to steep slopes subject to intense rainstorms. Individual landslides in rainstorm-triggered events are dominantly small, shallow debris and earth flows, and debris and earth slides involving regolith or weathered bedrock. The model used to characterise these events assumes that energy distribution within the event area is represented on the land surface by a cell structure; with maximum energy expenditure within an identifiable core and rapid dissipation concentrically away from the centre. The version of the model presented here has been developed for rainfall-triggered landslide events. It proposes that rainfall intensity can be used to determine different critical landslide response zones within the cell (referred to as core, middle, and periphery zones). These zones are most readily distinguished by two conditions: the proportion of the slope that fails and the particular type of the slope stability factor that assumes dominance in determining specific sites of landslide occurrence. The latter condition means that the power of any slope stability factor to distinguish between stable and unstable sites varies throughout the affected area in accordance with the landslide response zones within the cell; certain factors critical for determining the location of landslide sites in one part of the event area have little influence in other parts of the event area. The implication is that landslide susceptibility maps (and subsequently derived mitigation measures) based on conventional slope stability factors may have only limited validity for many events. The overall ability to predict the impact of these events and consequently the development of effective mitigation measures is limited by the ability to predict the travel path, storm centre, and intensity range within the cell structure of extreme weather systems.

  1. Reprint of "A proposed cell model for multiple-occurrence regional landslide events: Implications for landslide susceptibility mapping"

    NASA Astrophysics Data System (ADS)

    Crozier, M. J.

    2018-04-01

    Multiple-occurrence regional landslide events (MORLEs) consist of hundreds to thousands of shallow landslides occurring more or less simultaneously within defined areas, ranging from tens to thousands of square kilometres. While MORLEs can be triggered by rainstorms and earthquakes, this paper is confined to those landslide events triggered by rainstorms. Globally, MORLEs occur in a range of geological settings in areas of moderate to steep slopes subject to intense rainstorms. Individual landslides in rainstorm-triggered events are dominantly small, shallow debris and earth flows, and debris and earth slides involving regolith or weathered bedrock. The model used to characterise these events assumes that energy distribution within the event area is represented on the land surface by a cell structure; with maximum energy expenditure within an identifiable core and rapid dissipation concentrically away from the centre. The version of the model presented here has been developed for rainfall-triggered landslide events. It proposes that rainfall intensity can be used to determine different critical landslide response zones within the cell (referred to as core, middle, and periphery zones). These zones are most readily distinguished by two conditions: the proportion of the slope that fails and the particular type of the slope stability factor that assumes dominance in determining specific sites of landslide occurrence. The latter condition means that the power of any slope stability factor to distinguish between stable and unstable sites varies throughout the affected area in accordance with the landslide response zones within the cell; certain factors critical for determining the location of landslide sites in one part of the event area have little influence in other parts of the event area. The implication is that landslide susceptibility maps (and subsequently derived mitigation measures) based on conventional slope stability factors may have only limited validity for many events. The overall ability to predict the impact of these events and consequently the development of effective mitigation measures is limited by the ability to predict the travel path, storm centre, and intensity range within the cell structure of extreme weather systems.

  2. STAT3 Regulates Uterine Epithelial Remodeling and Epithelial-Stromal Crosstalk During Implantation

    PubMed Central

    Pawar, Sandeep; Starosvetsky, Elina; Orvis, Grant D.; Behringer, Richard R.; Bagchi, Indrani C.

    2013-01-01

    Embryo implantation is regulated by a variety of endometrial factors, including cytokines, growth factors, and transcription factors. Earlier studies identified the leukemia inhibitory factor (LIF), a cytokine produced by uterine glands, as an essential regulator of implantation. LIF, acting via its cell surface receptor, activates the signal transducer and activator of transcription 3 (STAT3) in the uterine epithelial cells. However, the precise mechanism via which activated STAT3 promotes uterine function during implantation remains unknown. To identify the molecular pathways regulated by STAT3, we created SWd/d mice in which Stat3 gene is conditionally inactivated in uterine epithelium. The SWd/d mice are infertile due to a lack of embryo attachment to the uterine luminal epithelium and consequent implantation failure. Gene expression profiling of uterine epithelial cells of SWd/d mice revealed dysregulated expression of specific components of junctional complexes, including E-cadherin, α- and β-catenin, and several claudins, which critically regulate epithelial junctional integrity and embryo attachment. In addition, uteri of SWd/d mice exhibited markedly reduced stromal proliferation and differentiation, indicating that epithelial STAT3 controls stromal function via a paracrine mechanism. The stromal defect arose from a drastic reduction in the production of several members of the epidermal growth factor family in luminal epithelium of SWd/d uteri and the resulting lack of activation of epidermal growth factor receptor signaling and mitotic activity in the stromal cells. Collectively, our results uncovered an intricate molecular network operating downstream of STAT3 that regulates uterine epithelial junctional reorganization, and stromal proliferation, and differentiation, which are critical determinants of successful implantation. PMID:24100212

  3. One-year mortality after recovery from critical illness: A retrospective cohort study.

    PubMed

    Lokhandwala, Sharukh; McCague, Ned; Chahin, Abdullah; Escobar, Braiam; Feng, Mengling; Ghassemi, Mohammad M; Stone, David J; Celi, Leo Anthony

    2018-01-01

    Factors associated with one-year mortality after recovery from critical illness are not well understood. Clinicians generally lack information regarding post-hospital discharge outcomes of patients from the intensive care unit, which may be important when counseling patients and families. We sought to determine which factors among patients who survived for at least 30 days post-ICU admission are associated with one-year mortality. Single-center, longitudinal retrospective cohort study of all ICU patients admitted to a tertiary-care academic medical center from 2001-2012 who survived ≥30 days from ICU admission. Cox's proportional hazards model was used to identify the variables that are associated with one-year mortality. The primary outcome was one-year mortality. 32,420 patients met the inclusion criteria and were included in the study. Among patients who survived to ≥30 days, 28,583 (88.2%) survived for greater than one year, whereas 3,837 (11.8%) did not. Variables associated with decreased one-year survival include: increased age, malignancy, number of hospital admissions within the prior year, duration of mechanical ventilation and vasoactive agent use, sepsis, history of congestive heart failure, end-stage renal disease, cirrhosis, chronic obstructive pulmonary disease, and the need for renal replacement therapy. Numerous effect modifications between these factors were found. Among survivors of critical illness, a significant number survive less than one year. More research is needed to help clinicians accurately identify those patients who, despite surviving their acute illness, are likely to suffer one-year mortality, and thereby to improve the quality of the decisions and care that impact this outcome.

  4. Exploitation of host cell cytoskeleton and signalling during Listeria monocytogenes entry into mammalian cells.

    PubMed

    Pizarro-Cerdá, Javier; Sousa, Sandra; Cossart, Pascale

    2004-02-01

    Deciphering how Listeria monocytogenes exploits the host cell machinery to invade mammalian cells during infection is a key issue for the understanding how this food-borne pathogen causes a pleiotropic disease ranging from gastro-enteritis to meningitis and abortions. Using multidisciplinary approaches, essentially combining bacterial genetics and cell biology, we have identified two bacterial proteins critical for entry into target cells, InlA and InlB. Their cellular ligands have been also identified: InlA interacts with the adhesion molecule E-cadherin, while InlB interacts with the receptor for the globular head of the complement factor C1q (gC1q-R), with the hepatocyte growth factor receptor (c-Met) and with glycosaminoglycans (including heparan sulphate). The dynamic interaction between these cellular receptors and the actin cytoskeleton is currently under investigation. Several intracellular molecules have been recognized as key effectors for Listeria entry into target cells, including catenins (implicated in the connection of E-cadherin to actin) and the actin depolymerising factor/cofilin (involved in the rearrangement of the cytoskeleton in the InlB-dependent internalisation pathway). At the organism level, species specificity has been discovered concerning the interaction between InlA and E-cadherin, leading to the generation of transgenic mice expressing the human E-cadherin, in which the critical role of InlA in the crossing of the intestinal barrier has been clearly determined. Listeria appears as an instrumental model for addressing critical questions concerning both the complex process of bacterial pathogenesis and also fundamental molecular processes, such as phagocytosis.

  5. Exploitation of host cell cytoskeleton and signalling during Listeria monocytogenes entry into mammalian cells.

    PubMed

    Pizarro-Cerdá, Javier; Sousa, Sandra; Cossart, Pascale

    2004-06-01

    Deciphering how Listeria monocytogenes exploits the host cell machinery to invade mammalian cells during infection isa key issue for the understanding how this food-borne pathogen causes a pleiotropic disease ranging from gastro-enteritis to meningitis and abortions. Using multidisciplinary approaches, essentially combining bacterial genetics and cell biology, we have identified two bacterial proteins critical for entry into target cells, InlA and InlB. Their cellular ligands have been also identified: InlA interacts with the adhesion molecule E-cadherin, while InlB interacts with the receptor for the globular head of the complement factor Clq (gClq-R), with the hepatocyte growth factor receptor (c-Met) and with glycosaminoglycans(including heparan sulphate). The dynamic interaction between these cellular receptors and the actin cytoskeleton is currently under investigation. Several intracellular molecules have been recognized as key effectors for Listeria entry into target cells,including catenins (implicated in the connection of E-cadherin to actin) and the actin depolymerising factor/cofilin (involved in the rearrangement of the cytoskeleton in the InlB-dependent internalisation pathway). At the organism level, species specificity has been discovered concerning the interaction between InlA and E-cadherin, leading to the generation of transgenic mice expressing the human E-cadherin, in which the critical role of InlA in the crossing of the intestinal barrier has been clearly determined. Listeria appears as an instrumental model for addressing critical questions concerning both the complex process of bacterial pathogenesis and also fundamental molecular processes, such as phagocytosis.

  6. Accurate Determination of Coulombic Efficiency for Lithium Metal Anodes and Lithium Metal Batteries

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

    Adams, Brian D.; Zheng, Jianming; Ren, Xiaodi

    Lithium (Li) metal is an ideal anode material for high energy density batteries. However, its low Coulombic efficiency (CE) and formation of dendrites during the plating and stripping processes has hindered its applications in rechargeable Li metal batteries. The accurate measurement of Li CE is a critical factor to predict the cycle life of Li metal batteries, but the measurement of Li CE is affected by various factors that often leads to conflicting values reported in the literature. Here, we investigate various factors that affect the measurement of Li CE and propose a more accurate method of determining Li CE.more » It was also found that the capacity used for cycling greatly affects the stabilization cycles and the average CE. A higher cycling capacity leads to a shorter number of stabilization cycles and higher average CE. With a proper high-concentration ether-based electrolyte, Li metal can be cycled with a high average CE of 99.5 % for over 100 cycles at a high capacity of 6 mAh cm-2 suitable for practical applications.« less

  7. Effects of Buckling Knockdown Factor, Internal Pressure and Material on the Design of Stiffened Cylinders

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.; Hilburger, Mark W.; Chunchu, Prasad B.

    2010-01-01

    A design study was conducted to investigate the effect shell buckling knockdown factor (SBKF), internal pressure and aluminum alloy material selection on the structural weight of stiffened cylindrical shells. Two structural optimization codes were used for the design study to determine the optimum minimum-weight design for a series of design cases, and included an in-house developed genetic algorithm (GA) code and PANDA2. Each design case specified a unique set of geometry, material, knockdown factor combinations and loads. The resulting designs were examined and compared to determine the effects of SBKF, internal pressure and material selection on the acreage design weight and controlling failure mode. This design study shows that use of less conservative SBKF values, including internal pressure, and proper selection of material alloy can result in significant weight savings for stiffened cylinders. In particular, buckling-critical cylinders with integrally machined stiffener construction can benefit from the use of thicker plate material that enables taller stiffeners, even when the stiffness, strength and density properties of these materials appear to be inferior.

  8. Maternal Lead Exposure Induces Down-regulation of Hippocampal Insulin-degrading Enzyme and Nerve Growth Factor Expression in Mouse Pups.

    PubMed

    Li, Xing; Li, Ning; Sun, Hua Lei; Yin, Jun; Tao, Yu Chang; Mao, Zhen Xing; Yu, Zeng Li; Li, Wen Jie; Bogden, John D

    2017-03-01

    Lead exposure is a known potential risk factor for neurodegenerative diseases such as Alzheimer's disease (AD). Exposure to lead during the critical phase of brain development has been linked with mental retardation and hypophrenia in later life. This study was aimed to investigate the effects of lead exposure of pregnant mice on the expressions of insulin-degrading enzyme (IDE) and nerve growth factor (NGF) in the hippocampus of their offspring. Blood samples were collected from the tail vein, and after anesthetizing the pups, the brain was excised on postnatal day 21. Lead concentrations were determined by graphite furnace atomic absorption spectrophotometry, and the expressions of IDE and NGF were determined by immunohistochemistry and Western blotting. Results showed that the reduction in IDE and NGF expression in the hippocampus of pups might be associated with impairment of learning and memory and dementia induced by maternal lead exposure during pregnancy and lactation. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  9. State of spermatogenesis in rats flown aboard Kosmos-690 biosatellite. [Effects of space flight factors on. gamma. radiosensitivity of germ cells in male rats

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

    Plakhuta-Plakutina, G.I.

    1978-10-26

    In studying the modifying effects of space flight factors on radiosensitivity of various physiological systems of the body, of definite interest is the reaction of critical organs, in particular the testes, which have a high degree of heterogenic sensitivity of spermatogenic epithelium. Impairment of proliferative activity of testicular epithelium is largely related to the radiovulnerability of cells of the stem type, spermatogonia. In determining the modifying effects of weightlessness and other factors of space flights, it is necessary to compare the cytological state and quantitative evaluation of the incidence of spermatogonia, spermatocytes, spermatids, and spermatozoa in order to determine themore » possible injury to specific stages of spectrogenesis, depending on the radiation doses during space flights and in ground-based model experiments. The effects of radiation under weightless conditions on the reproductive glands of 30 male Wistar rats flown aboard Kosmos-690 and submitted to prolonged ..gamma.. radiation on the 10th day of the flight were investigated.« less

  10. Sustainable development and next generation's health: a long-term perspective about the consequences of today's activities for food safety.

    PubMed

    Frazzoli, Chiara; Petrini, Carlo; Mantovani, Alberto

    2009-01-01

    Development is defined sustainable when it meets the needs of the present without compromising the ability of future generations to meet their own needs. Pivoting on social, environmental and economic aspects of food chain sustainability, this paper presents the concept of sustainable food safety based on the prevention of risks and burden of poor health for generations to come. Under this respect, the assessment of long-term, transgenerational risks is still hampered by serious scientific uncertainties. Critical issues to the development of a sustainable food safety framework may include: endocrine disrupters as emerging contaminants that specifically target developing organisms; toxicological risks assessment in Countries at the turning point of development; translating knowledge into toxicity indexes to support risk management approaches, such as hazard analysis and critical control points (HACCP); the interplay between chemical hazards and social determinants. Efforts towards the comprehensive knowledge and management of key factors of sustainable food safety appear critical to the effectiveness of the overall sustainability policies.

  11. Forbidden mass ranges for shower meteoroids

    NASA Astrophysics Data System (ADS)

    Moorhead, Althea V.

    2017-10-01

    Burns et al. (1979) use the parameter β to describe the ratio of radiation pressure to gravity for a particle in the Solar System. The central potential that these particles experience is effectively reduced by a factor of (1 - β), which in turn lowers the escape velocity. Burns et al. (1979) derived a simple expression for the value of β at which particles ejected from a comet follow parabolic orbits and thus leave the Solar System; we expand on this to derive an expression for critical β values that takes ejection velocity into account, assuming geometric optics. We use our expression to compute the critical β value and corresponding mass for cometary ejecta leading, trailing, and following the parent comet’s nucleus for 10 major meteor showers. Finally, we numerically solve for critical β values in the case of non-geometric optics. These values determine the mass regimes within which meteoroids are ejected from the Solar System and therefore cannot contribute to meteor showers.

  12. Forbidden Mass Ranges for Shower Meteoroids

    NASA Technical Reports Server (NTRS)

    Moorhead, Althea V.

    2017-01-01

    Burns et al. (1979) use the parameter beta to describe the ratio of radiation pressure to gravity for a particle in the Solar System. The central potential that these particles experience is effectively reduced by a factor of (1- beta ), which in turn lowers the escape velocity. Burns et al. (1979) derived a simple expression for the value of beta at which particles ejected from a comet follow parabolic orbits and thus leave the Solar System; we expand on this to derive an expression for critical beta values that takes ejection velocity into account, assuming geometric optics. We use our expression to compute the critical value and corresponding mass for cometary ejecta leading, trailing, and following the parent comet's nucleus for 10 major meteor showers. Finally, we numerically solve for critical beta values in the case of non-geometric optics. These values determine the mass regimes within which meteoroids are ejected from the Solar System and therefore cannot contribute to meteor showers.

  13. Influence of external factors on the self-assembly of two structurally related antidepressant drugs: a thermodynamic study

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Pichel, Manuel; Attwood, David; Taboada, Pablo; Mosquera, Víctor

    Apparent molal volumes and adiabatic compressibilities of aqueous solutions of the amphiphilic antidepressant drugs imipramine and desipramine hydrochlorides have been determined from density and ultrasound velocity measurements in the temperature range 288.15-313.15 K in buffered solution of pH 3.0 and 5.5. Critical concentrations for aggregation of these drugs were obtained from inflections on the plots of the sound velocity against drug concentration. Positive deviation from the Debye-Hückel limiting law of the apparent molal volume of imipramine provides evidence of limited association at concentrations below the critical concentration over the temperature range studied. Apparent molal adiabatic compressibilities of the aggregates formed by the drugs, calculated by combining the ultrasound velocity and density data, were typical of those for a stacked aggregate. The critical concentration and energy involved in the aggregation process of these drugs have been evaluated using isothermal titration calorimetry. The solvent-aggregate interactions have been discussed from compressibility and calorimetry data.

  14. Analysis of composite laminates with multiple fasteners by boundary collocation technique

    NASA Astrophysics Data System (ADS)

    Sergeev, Boris Anatolievich

    Mechanical fasteners remain the primary means of load transfer between structural components made of composite laminates. As, in pursuit of increasing efficiency of the structure, the operational load continues to grow, the load carried by each fastener increases accordingly. This accelerates initiation of fatigue-related cracks near the fasteners holes and increases probability of failure. Therefore, the assessment of the stresses around the fastener holes and the stress intensity factors associated with edge cracks becomes critical for damage-tolerant design. Because of the presence of unknown contact stresses and the contact region between the fastener and the laminate, the analysis of a pin-loaded hole becomes considerably more complex than that of a traction-free hole. The accurate prediction of the contact stress distribution along the hole boundary is critical for determining the stress intensity factors and is essential for reliable strength evaluation and failure prediction. This study concerns the development of an analytical methodology, based on the boundary collocation technique, to determine the contact stresses and stress intensity factors required for strength and life prediction of bolted joints with many fasteners. It provides an analytical capability for determining the non-linear contact stresses in mechanically fastened composite laminates while capturing the effects of finite geometry, presence of edge cracks, interaction among fasteners, material anisotropy, fastener flexibility, fastener-hole clearance, friction between the pin and the laminate, and by-pass loading. Also, the proposed approach permits the determination of the fastener load distribution, which significantly influences the failure load of a multi-fastener joint. The well known phenomenon of the fastener tightening torque (clamping force) influence on the load distribution among the different fastener in a multi-fastener joints is taken into account by means of bi-linear representation of the elastic fastener deflection. Finally, two different failure criteria, maximum strains averaged over the characteristic distances and Tsai-Wu criterion, were used to predict the failure load and failure mode in two composite-aluminum joints. The comparison of the present predictions with the published experimental results reveals their agreement.

  15. Neural Stem Cell Differentiation Using Microfluidic Device-Generated Growth Factor Gradient.

    PubMed

    Kim, Ji Hyeon; Sim, Jiyeon; Kim, Hyun-Jung

    2018-04-11

    Neural stem cells (NSCs) have the ability to self-renew and differentiate into multiple nervous system cell types. During embryonic development, the concentrations of soluble biological molecules have a critical role in controlling cell proliferation, migration, differentiation and apoptosis. In an effort to find optimal culture conditions for the generation of desired cell types in vitro , we used a microfluidic chip-generated growth factor gradient system. In the current study, NSCs in the microfluidic device remained healthy during the entire period of cell culture, and proliferated and differentiated in response to the concentration gradient of growth factors (epithermal growth factor and basic fibroblast growth factor). We also showed that overexpression of ASCL1 in NSCs increased neuronal differentiation depending on the concentration gradient of growth factors generated in the microfluidic gradient chip. The microfluidic system allowed us to study concentration-dependent effects of growth factors within a single device, while a traditional system requires multiple independent cultures using fixed growth factor concentrations. Our study suggests that the microfluidic gradient-generating chip is a powerful tool for determining the optimal culture conditions.

  16. Toward a definition of intolerance of uncertainty: a review of factor analytical studies of the Intolerance of Uncertainty Scale.

    PubMed

    Birrell, Jane; Meares, Kevin; Wilkinson, Andrew; Freeston, Mark

    2011-11-01

    Since its emergence in the early 1990s, a narrow but concentrated body of research has developed examining the role of intolerance of uncertainty (IU) in worry, and yet we still know little about its phenomenology. In an attempt to clarify our understanding of this construct, this paper traces the way in which our understanding and definition of IU have evolved throughout the literature. This paper also aims to further our understanding of IU by exploring the latent variables measures by the Intolerance of Uncertainty Scale (IUS; Freeston, Rheaume, Letarte, Dugas & Ladouceur, 1994). A review of the literature surrounding IU confirmed that the current definitions are categorical and lack specificity. A critical review of existing factor analytic studies was carried out in order to determine the underlying factors measured by the IUS. Systematic searches yielded 9 papers for review. Two factors with 12 consistent items emerged throughout the exploratory studies, and the stability of models containing these two factors was demonstrated in subsequent confirmatory studies. It is proposed that these factors represent (i) desire for predictability and an active engagement in seeking certainty, and (ii) paralysis of cognition and action in the face of uncertainty. It is suggested that these factors may represent approach and avoidance responses to uncertainty. Further research is required to confirm the construct validity of these factors and to determine the stability of this structure within clinical samples. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Damage Characterization Method for Structural Health Management Using Reduced Number of Sensor Inputs

    NASA Technical Reports Server (NTRS)

    Krishnamurthy, T.; Hochhalter, Jacob D.; Gallegos, Adam M.

    2012-01-01

    The development of validated multidisciplinary Integrated Vehicle Health Management (IVHM) tools, technologies, and techniques to enable detection, diagnosis, prognosis, and mitigation in the presence of adverse conditions during flight will provide effective solutions to deal with safety related challenges facing next generation aircraft. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and damage conditions. A major concern in these structures is the growth of undetected damage (cracks) due to fatigue and low velocity foreign impacts that can reach a critical size during flight, resulting in loss of control of the aircraft. Hence, development of efficient methodologies to determine the presence, location, and severity of damage in critical structural components is highly important in developing efficient structural health management systems.

  18. Damage Characterization Using the Extended Finite Element Method for Structural Health Management

    NASA Technical Reports Server (NTRS)

    Krishnamurthy, Thiagarajan; Gallegos, Adam M.

    2011-01-01

    The development of validated multidisciplinary Integrated Vehicle Health Management (IVHM) tools, technologies, and techniques to enable detection, diagnosis, prognosis, and mitigation in the presence of adverse conditions during flight will provide effective solutions to deal with safety related challenges facing next generation aircraft. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and damage conditions. A major concern in these structures is the growth of undetected damage/cracks due to fatigue and low velocity foreign impact that can reach a critical size during flight, resulting in loss of control of the aircraft. Hence, development of efficient methodologies to determine the presence, location, and severity of damage/cracks in critical structural components is highly important in developing efficient structural health management systems.

  19. Thermodynamics of micelle formation in a water-alcohol solution of sodium tetradecyl sulfate

    NASA Astrophysics Data System (ADS)

    Shilova, S. V.; Tret'yakova, A. Ya.; Barabanov, V. P.

    2016-01-01

    The effects of addition of ethanol and propan-1-ol on sodium tetradecyl sulfate micelle formation in an aqueous solution are studied via microprobe fluorescence microscopy and conductometry. The critical micelle concentration, quantitative characteristics of micelles, and thermodynamic parameters of micelle formation are determined. Addition of 5-15 vol % of ethanol or 5-10 vol % of propan-1-ol is shown to result in a lower critical micelle concentration than in the aqueous solution, and in the formation of mixed spherical micelles whose sizes and aggregation numbers are less than those for the systems without alcohol. The contribution from the enthalpy factor to the free energy of sodium tetradecyl sulfate micelle formation is found to dominate in mixed solvents, in contrast to aqueous solutions.

  20. Transcriptional integration of mitogenic and mechanical signals by Myc and YAP

    PubMed Central

    Croci, Ottavio; De Fazio, Serena; Biagioni, Francesca; Donato, Elisa; Caganova, Marieta; Curti, Laura; Doni, Mirko; Sberna, Silvia; Aldeghi, Deborah; Biancotto, Chiara; Verrecchia, Alessandro; Olivero, Daniela; Amati, Bruno

    2017-01-01

    Mammalian cells must integrate environmental cues to determine coherent physiological responses. The transcription factors Myc and YAP–TEAD act downstream from mitogenic signals, with the latter responding also to mechanical cues. Here, we show that these factors coordinately regulate genes required for cell proliferation. Activation of Myc led to extensive association with its genomic targets, most of which were prebound by TEAD. At these loci, recruitment of YAP was Myc-dependent and led to full transcriptional activation. This cooperation was critical for cell cycle entry, organ growth, and tumorigenesis. Thus, Myc and YAP–TEAD integrate mitogenic and mechanical cues at the transcriptional level to provide multifactorial control of cell proliferation. PMID:29141911

  1. Analysis of a Preloaded Bolted Joint in a Ceramic Composite Combustor

    NASA Technical Reports Server (NTRS)

    Hissam, D. Andy; Bower, Mark V.

    2003-01-01

    This paper presents the detailed analysis of a preloaded bolted joint incorporating ceramic materials. The objective of this analysis is to determine the suitability of a joint design for a ceramic combustor. The analysis addresses critical factors in bolted joint design including preload, preload uncertainty, and load factor. The relationship between key joint variables is also investigated. The analysis is based on four key design criteria, each addressing an anticipated failure mode. The criteria are defined in terms of margin of safety, which must be greater than zero for the design criteria to be satisfied. Since the proposed joint has positive margins of safety, the design criteria are satisfied. Therefore, the joint design is acceptable.

  2. Genetics of ischemic stroke: future clinical applications.

    PubMed

    Wang, Michael M

    2006-11-01

    Ischemic stroke has long been thought to have a genetic component that is independent of conventional vascular risk factors. It has been estimated that over one half of stroke risk is determined by inherited genes. However, until recently, strong evidence of genetic influence on ischemic stroke has been subject to criticism because the risk factors for stroke are also inherited and because previous studies suffered from limitations imposed by this highly heterogeneous neurological disorder. Recent advances in molecular genetics have led to the identification of specific genetic loci that impart susceptibility to ischemic stroke. We review the studies of these genes and discuss the future potential applications of genetic markers on the management of ischemic stroke patients.

  3. When Does Changing Representation Improve Problem-Solving Performance?

    NASA Technical Reports Server (NTRS)

    Holte, Robert; Zimmer, Robert; MacDonald, Alan

    1992-01-01

    The aim of changing representation is the improvement of problem-solving efficiency. For the most widely studied family of methods of change of representation it is shown that the value of a single parameter, called the expulsion factor, is critical in determining (1) whether the change of representation will improve or degrade problem-solving efficiency and (2) whether the solutions produced using the change of representation will or will not be exponentially longer than the shortest solution. A method of computing the expansion factor for a given change of representation is sketched in general and described in detail for homomorphic changes of representation. The results are illustrated with homomorphic decompositions of the Towers of Hanoi problem.

  4. Smile attractiveness. Self-perception and influence on personality.

    PubMed

    Van der Geld, Pieter; Oosterveld, Paul; Van Heck, Guus; Kuijpers-Jagtman, Anne Marie

    2007-09-01

    To investigate self-perception of smile attractiveness and to determine the role of smile line and other aspects correlated with smile attractiveness and their influence on personality traits. Participants judged their smile attractiveness with a patient-specific questionnaire. The questionnaire contained a spontaneous smiling photograph of the participant. Objective smile-line height was measured using a digital videographic method for smile analysis. Personality was assessed with the Dutch Personality Index. Cronbach's alpha for the smile judgment questionnaire was .77. The results showed that size of teeth, visibility of teeth, and upper lip position were critical factors in self-perception of smile attractiveness (social dimension). Color of teeth and gingival display were critical factors in satisfaction with smile appearance (individual dimension). Participants, smiling with teeth entirely displayed and some gingival display (two to four millimeters), perceived their smile line as most esthetic. Smiles with disproportional gingival display were judged negatively and correlated with the personality characteristics of neuroticism and self-esteem. Visibility and position of teeth correlated with dominance. The results of this research underpin the psychosocial importance and the dental significance of an attractive smile.

  5. History of health, a valuable tool in public health

    PubMed Central

    Perdiguero, E; Bernabeu, J; Huertas, R; Rodriguez-Ocana, E

    2001-01-01

    The aim of this article is to highlight the importance of the history of public health for public health research and practice itself. After summarily reviewing the current great vitality of the history of collective health oriented initiatives, we explain three particular features of the historical vantage point in public health, namely the importance of the context, the relevance of a diachronic attitude and the critical perspective. In order to illustrate those three topics, we bring up examples taken from three centuries of fight against malaria, the so called "re-emerging diseases" and the 1918 influenza epidemic. The historical approach enriches our critical perception of the social effects of initiatives undertaken in the name of public health, shows the shortcomings of public health interventions based on single factors and asks for a wider time scope in the assessment of current problems. The use of a historical perspective to examine the plurality of determinants in any particular health condition will help to solve the longlasting debate on the primacy of individual versus population factors, which has been particularly intense in recent times.


Keywords: history PMID:11511647

  6. High- to low-dose extrapolation: critical determinants involved in the dose response of carcinogenic substances.

    PubMed

    Swenberg, J A; Richardson, F C; Boucheron, J A; Deal, F H; Belinsky, S A; Charbonneau, M; Short, B G

    1987-12-01

    Recent investigations on mechanism of carcinogenesis have demonstrated important quantitative relationships between the induction of neoplasia, the molecular dose of promutagenic DNA adducts and their efficiency for causing base-pair mismatch, and the extent of cell proliferation in target organ. These factors are involved in the multistage process of carcinogenesis, including initiation, promotion, and progression. The molecular dose of DNA adducts can exhibit supralinear, linear, or sublinear relationships to external dose due to differences in absorption, biotransformation, and DNA repair at high versus low doses. In contrast, increased cell proliferation is a common phenomena that is associated with exposures to relatively high doses of toxic chemicals. As such, it enhances the carcinogenic response at high doses, but has little effect at low doses. Since data on cell proliferation can be obtained for any exposure scenario and molecular dosimetry studies are beginning to emerge on selected chemical carcinogens, methods are needed so that these critical factors can be utilized in extrapolation from high to low doses and across species. The use of such information may provide a scientific basis for quantitative risk assessment.

  7. High- to low-dose extrapolation: critical determinants involved in the dose response of carcinogenic substances.

    PubMed Central

    Swenberg, J A; Richardson, F C; Boucheron, J A; Deal, F H; Belinsky, S A; Charbonneau, M; Short, B G

    1987-01-01

    Recent investigations on mechanism of carcinogenesis have demonstrated important quantitative relationships between the induction of neoplasia, the molecular dose of promutagenic DNA adducts and their efficiency for causing base-pair mismatch, and the extent of cell proliferation in target organ. These factors are involved in the multistage process of carcinogenesis, including initiation, promotion, and progression. The molecular dose of DNA adducts can exhibit supralinear, linear, or sublinear relationships to external dose due to differences in absorption, biotransformation, and DNA repair at high versus low doses. In contrast, increased cell proliferation is a common phenomena that is associated with exposures to relatively high doses of toxic chemicals. As such, it enhances the carcinogenic response at high doses, but has little effect at low doses. Since data on cell proliferation can be obtained for any exposure scenario and molecular dosimetry studies are beginning to emerge on selected chemical carcinogens, methods are needed so that these critical factors can be utilized in extrapolation from high to low doses and across species. The use of such information may provide a scientific basis for quantitative risk assessment. PMID:3447904

  8. History of health, a valuable tool in public health.

    PubMed

    Perdiguero, E; Bernabeu, J; Huertas, R; Rodríguez-Ocaña, E

    2001-09-01

    The aim of this article is to highlight the importance of the history of public health for public health research and practice itself. After summarily reviewing the current great vitality of the history of collective health oriented initiatives, we explain three particular features of the historical vantage point in public health, namely the importance of the context, the relevance of a diachronic attitude and the critical perspective. In order to illustrate those three topics, we bring up examples taken from three centuries of fight against malaria, the so called "re-emerging diseases" and the 1918 influenza epidemic. The historical approach enriches our critical perception of the social effects of initiatives undertaken in the name of public health, shows the shortcomings of public health interventions based on single factors and asks for a wider time scope in the assessment of current problems. The use of a historical perspective to examine the plurality of determinants in any particular health condition will help to solve the longlasting debate on the primacy of individual versus population factors, which has been particularly intense in recent times.

  9. Association of market, operational, and financial factors with nonprofit hospitals' capital investment.

    PubMed

    Kim, Tae Hyun; McCue, Michael J

    2008-01-01

    Capital investments in the latest medical equipment and the replacement of aging facilities are critical decisions for sustaining hospitals' financial viability. A recent survey over the period 1997 to 2001 found that hospitals increased their capital expenditures by only 1%. The aim of this study is to gain insight into the changes in market, operational, and financial factors that may have influenced hospital capital investment during this period. The sample consisted of a panel of nonprofit hospitals operating between 1998 and 2001. Capital investment was measured on the basis of capital purchases for buildings, fixtures, and movable equipment during a fiscal year. The results suggest that liquidity-the availability of internal funds-is a critical determinant of capital investment in both urban and rural facilities. From a market perspective, findings indicate that growth in the over-65 population led to increases in the capital investment of rural hospitals. Financially, an increase in cash flow also was strongly related to a change in capital investment among urban facilities. Surprisingly, rural hospitals with aging plants and equipment had declining capital investment.

  10. Macromolecular refinement by model morphing using non-atomic parameterizations.

    PubMed

    Cowtan, Kevin; Agirre, Jon

    2018-02-01

    Refinement is a critical step in the determination of a model which explains the crystallographic observations and thus best accounts for the missing phase components. The scattering density is usually described in terms of atomic parameters; however, in macromolecular crystallography the resolution of the data is generally insufficient to determine the values of these parameters for individual atoms. Stereochemical and geometric restraints are used to provide additional information, but produce interrelationships between parameters which slow convergence, resulting in longer refinement times. An alternative approach is proposed in which parameters are not attached to atoms, but to regions of the electron-density map. These parameters can move the density or change the local temperature factor to better explain the structure factors. Varying the size of the region which determines the parameters at a particular position in the map allows the method to be applied at different resolutions without the use of restraints. Potential applications include initial refinement of molecular-replacement models with domain motions, and potentially the use of electron density from other sources such as electron cryo-microscopy (cryo-EM) as the refinement model.

  11. Effect of supercoiling on formation of protein-mediated DNA loops

    NASA Astrophysics Data System (ADS)

    Purohit, P. K.; Nelson, P. C.

    2006-12-01

    DNA loop formation is one of several mechanisms used by organisms to regulate genes. The free energy of forming a loop is an important factor in determining whether the associated gene is switched on or off. In this paper we use an elastic rod model of DNA to determine the free energy of forming short (50-100 basepair), protein mediated DNA loops. Superhelical stress in the DNA of living cells is a critical factor determining the energetics of loop formation, and we explicitly account for it in our calculations. The repressor protein itself is regarded as a rigid coupler; its geometry enters the problem through the boundary conditions it applies on the DNA. We show that a theory with these ingredients is sufficient to explain certain features observed in modulation of in vivo gene activity as a function of the distance between operator sites for the lac repressor. We also use our theory to make quantitative predictions for the dependence of looping on superhelical stress, which may be testable both in vivo and in single-molecule experiments such as the tethered particle assay and the magnetic bead assay.

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

    McAdams, Brian J.; Pearson, Raymond A.

    With the continuing trend of decreasing feature sizes in flip-chip assemblies, the reliability tolerance to interfacial flaws is also decreasing. Small-scale disbonds will become more of a concern, pointing to the need for a better understanding of the initiation stage of interfacial delamination. With most accepted adhesion metric methodologies tailored to predict failure under the prior existence of a disbond, the study of the initiation phenomenon is open to development and standardization of new testing procedures. Traditional fracture mechanics approaches are not suitable, as the mathematics assume failure to originate at a disbond or crack tip. Disbond initiation is believedmore » to first occur at free edges and corners, which act as high stress concentration sites and exhibit singular stresses similar to a crack tip, though less severe in intensity. As such, a 'fracture mechanics-like' approach may be employed which defines a material parameter--a critical stress intensity factor (K{sub c})--that can be used to predict when initiation of a disbond at an interface will occur. The factors affecting the adhesion of underfill/polyimide interfaces relevant to flip-chip assemblies were investigated in this study. The study consisted of two distinct parts: a comparison of the initiation and propagation phenomena and a comparison of the relationship between sub-critical and critical initiation of interfacial failure. The initiation of underfill interfacial failure was studied by characterizing failure at a free-edge with a critical stress intensity factor. In comparison with the interfacial fracture toughness testing, it was shown that a good correlation exists between the initiation and propagation of interfacial failures. Such a correlation justifies the continuing use of fracture mechanics to predict the reliability of flip-chip packages. The second aspect of the research involved fatigue testing of tensile butt joint specimens to determine lifetimes at sub-critical load levels. The results display an interfacial strength ranking similar to that observed during monotonic testing. The fatigue results indicate that monotonic fracture mechanics testing may be an adequate screening tool to help predict cyclic underfill failure; however lifetime data is required to predict reliability.« less

  13. Critical-Thinking Grudge Match: Biology vs. Chemistry--Examining Factors That Affect Thinking Skill in Nonmajors Science

    ERIC Educational Resources Information Center

    Quitadamo, Ian J.; Kurtz, Martha J.; Cornell, Caitlyn Nicole; Griffith, Lindsay; Hancock, Julie; Egbert, Brandi

    2011-01-01

    Chemistry students appear to bring significantly higher critical-thinking skill to their nonmajors course than do biology students. Knowing student preconceptions and thinking ability is essential to learning growth and effective teaching. Of the factors investigated, ethnicity and high school physics had the largest impact on critical-thinking…

  14. Meteorology and ethnicity as critical factors in HRIPT: Comparing responses between Chinese and Indian ethnicities.

    PubMed

    Yuan, Chao; Wang, Xue-Min; Galzote, Carlos; Tan, Yi-Mei; Bhagat, Kamlesh V; Yuan, Zhi-Kang; Du, Jian-Fei; Tan, Yuan

    2013-06-01

    Human repeated insult patch test (HRIPT) is regarded as one of the confirmatory test in determining the safety of skin sensitizers. A number of important factors should be considered when conducting and interpreting the results of the HRIPT. To investigate for probable critical factors that influence the results of HRIPT with the same protocol in Shanghai and Mumbai. Two HRIPTs were carried out in Shanghai and Mumbai in 2011. Six identical products and 1% sodium lauryl sulfate were tested. Two Chinese dermatologists performed the grading in the two cities. Climate conditions of Shanghai and Mumbai were also recorded. For four lower reaction ratio products, cumulative irritation scores in the induction phase were higher in individuals whose ethnicity was Indian rather than Chinese. Reaction ratio of the same four products was highly correlated to the climatic parameters. The other two higher reaction ratio products and the positive control had no difference between the two ethnicities. Greater attention ought to be paid to the impact of climate on the results of HRIPT, especially for the mild irritation cosmetics when giving the interpretation. Greater emphasis also needs to be placed on the ethnicity of the subjects. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

  15. Predictors of PTSD symptoms in Brazilian police officers: the synergy of negative affect and peritraumatic dissociation

    PubMed Central

    Maia, Deborah B.; Marmar, Charles R.; Henn-Haase, Clare; Nóbrega, Augusta; Fiszman, Adriana; Marques-Portella, Carla; Mendlowicz, Mauro V.; Coutinho, Evandro S.F.; Figueira, Ivan

    2013-01-01

    Background Exposure to traumatic events is a necessary but not a sufficient condition for the development of posttraumatic stress disorder (PTSD). Pretrauma, peritrauma and posttrauma factors interact to impact on symptom severity. The aim of the present study is to determine risk factors for PTSD symptoms in Brazilian police officers. Method In a cross-sectional sample of active duty officers (n = 212), participants were asked to complete a socio-demographic questionnaire and self-report scales on affective traits, cumulative critical incident exposure, peritraumatic distress and dissociation, PTSD symptoms, and social support. Hierarchical linear regression analysis was conducted to examine predictors of PTSD symptoms. Results Variables related to negative affect, job duration, frequency of critical incident exposure, peritraumatic dissociation, and lack of social support remained significant in the final model and explained 55% of the variance in PTSD symptoms. When interaction terms were evaluated, a synergistic effect between negative affect and peritraumatic dissociation was found. Conclusions The risk factors found in this study provide clues on how to elaborate primary prevention strategies regarding PTSD symptoms in police officers. Such initiatives may lessen the impact of repeated exposure to traumatic events on police officers over the course of their careers. PMID:22189925

  16. Transcription factor TLX1 controls retinoic acid signaling to ensure spleen development

    PubMed Central

    Lenti, Elisa; Farinello, Diego; Penkov, Dmitry; Castagnaro, Laura; Lavorgna, Giovanni; Wuputra, Kenly; Tjaden, Naomi E. Butler; Bernassola, Francesca; Caridi, Nicoletta; Wagner, Michael; Kozinc, Katja; Niederreither, Karen; Blasi, Francesco; Pasini, Diego; Trainor, Paul A.

    2016-01-01

    The molecular mechanisms that underlie spleen development and congenital asplenia, a condition linked to increased risk of overwhelming infections, remain largely unknown. The transcription factor TLX1 controls cell fate specification and organ expansion during spleen development, and Tlx1 deletion causes asplenia in mice. Deregulation of TLX1 expression has recently been proposed in the pathogenesis of congenital asplenia in patients carrying mutations of the gene-encoding transcription factor SF-1. Herein, we have shown that TLX1-dependent regulation of retinoic acid (RA) metabolism is critical for spleen organogenesis. In a murine model, loss of Tlx1 during formation of the splenic anlage increased RA signaling by regulating several genes involved in RA metabolism. Uncontrolled RA activity resulted in premature differentiation of mesenchymal cells and reduced vasculogenesis of the splenic primordium. Pharmacological inhibition of RA signaling in Tlx1-deficient animals partially rescued the spleen defect. Finally, spleen growth was impaired in mice lacking either cytochrome P450 26B1 (Cyp26b1), which results in excess RA, or retinol dehydrogenase 10 (Rdh10), which results in RA deficiency. Together, these findings establish TLX1 as a critical regulator of RA metabolism and provide mechanistic insights into the molecular determinants of human congenital asplenia. PMID:27214556

  17. Turbidity of a Binary Fluid Mixture: Determining Eta

    NASA Technical Reports Server (NTRS)

    Jacobs, Donald T.

    1996-01-01

    A ground based (1-g) experiment is in progress that will measure the turbidity of a density-matched, binary fluid mixture extremely close to its liquid-liquid critical point. By covering the range of reduced temperatures t equivalent to (T-T(sub c)) / T(sub c) from 10(exp -8) to 10(exp -2), the turbidity measurements will allow the critical exponent eta to be determined. No experiment has precisely determined a value of the critical exponent eta, yet its value is significant to theorists in critical phenomena. Relatively simple critical phenomena, as in the liquid-liquid system studied here, serve as model systems for more complex systems near a critical point.

  18. Studies of the structure-activity relationships of peptides and proteins involved in growth and development based on their three-dimensional structures.

    PubMed

    Nagata, Koji

    2010-01-01

    Peptides and proteins with similar amino acid sequences can have different biological functions. Knowledge of their three-dimensional molecular structures is critically important in identifying their functional determinants. In this review, I describe the results of our and other groups' structure-based functional characterization of insect insulin-like peptides, a crustacean hyperglycemic hormone-family peptide, a mammalian epidermal growth factor-family protein, and an intracellular signaling domain that recognizes proline-rich sequence.

  19. Pathogenesis and prevention of type 2 diabetes: parental determinants, breastfeeding, and early childhood nutrition.

    PubMed

    Bartz, Sarah; Freemark, Michael

    2012-02-01

    Among the factors predisposing to type 2 diabetes in children, adolescents, and young adults, the health and behavior of both the mother and father are critical. Prevention and treatment of parental nutritional disorders (including obesity and malnutrition), promotion of breastfeeding, and avoidance of overfeeding of young children are essential for childhood health and metabolic function. Focusing research and policy on parental influences on childhood health should reduce the risks of obesity and type 2 diabetes in future generations.

  20. When training boomerangs - Negative outcomes associated with Cockpit Resource Management programs

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.; Wilhelm, John A.

    1989-01-01

    Participants' self-reports and measures of attitudes regarding flightdeck management indicate that Cockpit Resource Management training is positively received and causes highly significant changes in attitudes regarding crew coordination and personal capabilities. However, a subset of participants react negatively to the training and show boomerangs (negative change) in attitudes. Explorations into the causes of this effect pinpoint personality factors and group dynamics as critical determinants of reactions to training and the magnitude and direction of attitude change.

  1. Metallurgical Aspects of Layered Cracks in Hot-Rolled Plates

    NASA Astrophysics Data System (ADS)

    Farber, V. M.; Arabey, A. B.; Khotinov, V. A.; Morozova, A. N.; Karabanalov, M. S.

    2018-03-01

    The nature of separations arising in hot-rolled plates from high-toughness steels of the new generation like 05G2B and of cleavages arising in traditional building steels of type 09G2S is studied. Like and unlike features of separations and cleavages are determined. The concept of "critical stress σb^{cr} " describing the strength of the interlayer boundaries responsible for formation of layered cracks is used to analyze various factors responsible for the susceptibility of rolled plates to layered fracture.

  2. An intelligent interface for satellite operations: Your Orbit Determination Assistant (YODA)

    NASA Technical Reports Server (NTRS)

    Schur, Anne

    1988-01-01

    An intelligent interface is often characterized by the ability to adapt evaluation criteria as the environment and user goals change. Some factors that impact these adaptations are redefinition of task goals and, hence, user requirements; time criticality; and system status. To implement adaptations affected by these factors, a new set of capabilities must be incorporated into the human-computer interface design. These capabilities include: (1) dynamic update and removal of control states based on user inputs, (2) generation and removal of logical dependencies as change occurs, (3) uniform and smooth interfacing to numerous processes, databases, and expert systems, and (4) unobtrusive on-line assistance to users of concepts were applied and incorporated into a human-computer interface using artificial intelligence techniques to create a prototype expert system, Your Orbit Determination Assistant (YODA). YODA is a smart interface that supports, in real teime, orbit analysts who must determine the location of a satellite during the station acquisition phase of a mission. Also described is the integration of four knowledge sources required to support the orbit determination assistant: orbital mechanics, spacecraft specifications, characteristics of the mission support software, and orbit analyst experience. This initial effort is continuing with expansion of YODA's capabilities, including evaluation of results of the orbit determination task.

  3. Contributions of Teachers' Thinking Styles to Critical Thinking Dispositions (Istanbul-Fatih Sample)

    ERIC Educational Resources Information Center

    Emir, Serap

    2013-01-01

    The main purpose of the research was to determine the contributions of the teachers' thinking styles to critical thinking dispositions. Hence, it is aimed to determine whether thinking styles are related to critical thinking dispositions and thinking styles measure critical thinking dispositions or not. The research was designed in relational…

  4. Critical biological parameters modulate affinity as a determinant of function in T-cell receptor gene-modified T-cells.

    PubMed

    Spear, Timothy T; Wang, Yuan; Foley, Kendra C; Murray, David C; Scurti, Gina M; Simms, Patricia E; Garrett-Mayer, Elizabeth; Hellman, Lance M; Baker, Brian M; Nishimura, Michael I

    2017-11-01

    T-cell receptor (TCR)-pMHC affinity has been generally accepted to be the most important factor dictating antigen recognition in gene-modified T-cells. As such, there is great interest in optimizing TCR-based immunotherapies by enhancing TCR affinity to augment the therapeutic benefit of TCR gene-modified T-cells in cancer patients. However, recent clinical trials using affinity-enhanced TCRs in adoptive cell transfer (ACT) have observed unintended and serious adverse events, including death, attributed to unpredicted off-tumor or off-target cross-reactivity. It is critical to re-evaluate the importance of other biophysical, structural, or cellular factors that drive the reactivity of TCR gene-modified T-cells. Using a model for altered antigen recognition, we determined how TCR-pMHC affinity influenced the reactivity of hepatitis C virus (HCV) TCR gene-modified T-cells against a panel of naturally occurring HCV peptides and HCV-expressing tumor targets. The impact of other factors, such as TCR-pMHC stabilization and signaling contributions by the CD8 co-receptor, as well as antigen and TCR density were also evaluated. We found that changes in TCR-pMHC affinity did not always predict or dictate IFNγ release or degranulation by TCR gene-modified T-cells, suggesting that less emphasis might need to be placed on TCR-pMHC affinity as a means of predicting or augmenting the therapeutic potential of TCR gene-modified T-cells used in ACT. A more complete understanding of antigen recognition by gene-modified T-cells and a more rational approach to improve the design and implementation of novel TCR-based immunotherapies is necessary to enhance efficacy and maximize safety in patients.

  5. Critical Elements in Fly Ash from the Combustion of Bituminous Coal in Major Polish Power Plants

    NASA Astrophysics Data System (ADS)

    Bielowicz, Barbara; Botor, Dariusz; Misiak, Jacek; Wagner, Marian

    2018-03-01

    The concentration of critical elements, including such REE as Fe, Co, W, Zn, Cr, Ni, V, Mn, Ti, Ag, Ga, Ta, Sr, Li, and Cu, in the so-called fly ash obtained from the 9 Polish power plants and 1 thermal power station has been determined. The obtained values, compared with the global average concentration in bituminous coal ash and sedimentary rocks (Clarke values), have shown that the enrichment of fly ash in the specified elements takes place in only a few bituminous coal processing sites in Poland. The enrichment factor (EF) is only slightly higher (the same order of magnitude) than the Clarke values. The enrichment factor in relation to the Clarke value in the Earth's crust reached values above 10 in all of the examined ashes for the following elements: Cr, Ni, V, W, and, in some ash samples, also Cu and Zn. The obtained values are low, only slightly higher than the global average concentrations in sedimentary rocks and bituminous coal ashes. The ferromagnetic grains (microspheres) found in bituminous coal fly ashes seem to be the most economically prospective in recovery of selected critical elements. The microanalysis has shown that iron cenospheres and plerospheres in fly ash contain, in addition to enamel and iron oxides (magnetite and hematite), iron spinels enriched in Co, Cr, Cu, Mn, Ni, W, and Zn.

  6. A critical review on physical factors and functional characteristics that may explain a sex/gender difference in work-related neck/shoulder disorders.

    PubMed

    Côté, Julie N

    2012-01-01

    The objective of this paper is to critically review recent literature on physical and functional sex/gender (s/g) differences, with focus on physical determinants associated with neck/shoulder musculoskeletal injuries. It is well known that there are s/g differences in anthropometrical and functional body characteristics (e.g. size and strength). However, s/g differences may be wrongly attributed if data analysis does not include appropriate corrections (e.g. by strength for endurance). Recent literature on motor control shows that there may indeed be s/g differences in muscle coordination and movement strategies during upper limb tasks that are not currently explained by methodological inadequacies. Moreover, recent studies have shown differences between men and women in sensory hypersensitivity characteristics associated with neck/shoulder injuries. Taken together, the literature points to the importance of accounting for possible s/g differences at all levels of the biopsychosocial system in order to better understand sex- and gender-specific issues relevant to workplace health. This article critically reviews recent literature and a conceptual model highlighting s/g differences in physical and functional characteristics related to neck/shoulder musculoskeletal disorders (NSMSD). Findings have implications on understanding how personal factors may affect NSMSD risk. With better understanding, practitioners can make more appropriate decisions to prevent work-related NSMSD.

  7. A Novel Method of Evaluating Key Factors for Success in a Multifaceted Critical Care Fellowship Using Data Envelopment Analysis.

    PubMed

    Tiwari, Vikram; Kumar, Avinash B

    2018-01-01

    The current system of summative multi-rater evaluations and standardized tests to determine readiness to graduate from critical care fellowships has limitations. We sought to pilot the use of data envelopment analysis (DEA) to assess what aspects of the fellowship program contribute the most to an individual fellow's success. DEA is a nonparametric, operations research technique that uses linear programming to determine the technical efficiency of an entity based on its relative usage of resources in producing the outcome. Retrospective cohort study. Critical care fellows (n = 15) in an Accreditation Council for Graduate Medical Education (ACGME) accredited fellowship at a major academic medical center in the United States. After obtaining institutional review board approval for this retrospective study, we analyzed the data of 15 anesthesiology critical care fellows from academic years 2013-2015. The input-oriented DEA model develops a composite score for each fellow based on multiple inputs and outputs. The inputs included the didactic sessions attended, the ratio of clinical duty works hours to the procedures performed (work intensity index), and the outputs were the Multidisciplinary Critical Care Knowledge Assessment Program (MCCKAP) score and summative evaluations of fellows. A DEA efficiency score that ranged from 0 to 1 was generated for each of the fellows. Five fellows were rated as DEA efficient, and 10 fellows were characterized in the DEA inefficient group. The model was able to forecast the level of effort needed for each inefficient fellow, to achieve similar outputs as their best performing peers. The model also identified the work intensity index as the key element that characterized the best performers in our fellowship. DEA is a feasible method of objectively evaluating peer performance in a critical care fellowship beyond summative evaluations alone and can potentially be a powerful tool to guide individual performance during the fellowship.

  8. Associations between errors and contributing factors in aircraft maintenance

    NASA Technical Reports Server (NTRS)

    Hobbs, Alan; Williamson, Ann

    2003-01-01

    In recent years cognitive error models have provided insights into the unsafe acts that lead to many accidents in safety-critical environments. Most models of accident causation are based on the notion that human errors occur in the context of contributing factors. However, there is a lack of published information on possible links between specific errors and contributing factors. A total of 619 safety occurrences involving aircraft maintenance were reported using a self-completed questionnaire. Of these occurrences, 96% were related to the actions of maintenance personnel. The types of errors that were involved, and the contributing factors associated with those actions, were determined. Each type of error was associated with a particular set of contributing factors and with specific occurrence outcomes. Among the associations were links between memory lapses and fatigue and between rule violations and time pressure. Potential applications of this research include assisting with the design of accident prevention strategies, the estimation of human error probabilities, and the monitoring of organizational safety performance.

  9. Growth characteristics of a plane crack subjected to three-dimensional loading. [based on stress intensity factors

    NASA Technical Reports Server (NTRS)

    Hartranft, R. J.; Sih, G. C.

    1973-01-01

    The closed form expressions for the stress intensity factors due to concentrated forces applied to the surfaces of a half plane crack in an infinite body are used to generate solutions for distributed loads in this geometry. The stress intensity factors for uniformly distributed loads applied over a rectangular portion of the crack surface are given in closed form. An example of non-uniformly distributed loads which can be treated numerically is also included. In particular, combinations of normal and shear stresses on the crack which simulate the case of loading at an angle to the crack front are considered. The resulting stress intensity factors are combined with the strain energy density fracture criterion for the purpose of predicting the most likely direction of crack propagation. The critical value of the energy density factor can then be used for determining the allowable load on a specimen with a crack front not perpendicular to the tensile axis.

  10. The main factor affecting the competitiveness of Contractor Company

    NASA Astrophysics Data System (ADS)

    Nurisra; Malahayati, Nurul; Mahmuddin

    2018-05-01

    Contractor companies must have the competitive advantage to compete in maintaining the survival of the company. Problems arise because quite a lot of advantages can be used and these advantages must be used appropriately to produce competitiveness for the company to continue to compete and to win the competition. This study aims to determine the main factors affecting the competitiveness of medium-class contractors in Banda Aceh. Data collection was obtained through questionnaires distributed to 31 middle-class contractors in Banda Aceh. Data processing and analysis is done by using descriptive analysis. Based on the result of descriptive analysis, it can be concluded that the most important competitiveness factor with a mean score value 4.52 is the relationship, and the factor that has the highest mean score value is the relationship with the government of 4.97, while the result of the ranking analysis is obtained 25 factor that is critical to the competitiveness of medium-class contractors in Banda Aceh.

  11. A Qualitative Comparison of Susceptibility and Behavior in Recreational and Occupational Risk Environments: Implications for Promoting Health and Safety.

    PubMed

    Haas, Emily Joy; Mattson, Marifran

    2016-06-01

    Although internal factors that influence risk are frequently studied to understand human behavior, external factors, including social, cultural, and institutional factors, should be better utilized to inform ways to efficiently target, tailor, and promote safety messaging to at-risk populations. Semi-structured interviews obtained data from 37 motorcyclists and 18 mineworkers about their risk perceptions and behaviors within their respective dynamic environments. A comparative thematic analysis revealed information about external factors that influence risk perceptions and behaviors. Results support the importance of qualitative approaches for assessing and targeting individuals' risk perceptions and behaviors. In addition, segmenting at-risk subgroups within target populations and tailoring messages for these at-risk groups is critical for safety behavior modification. Practitioners should utilize strategic, culture-centric risk communication that takes into account external factors when determining when, who, and what to communicate via health promotion activities to more accurately disseminate valid, empathetic, and engaging communication with a higher level of fidelity.

  12. Refreeze experiments with water droplets containing different types of ice nuclei interpreted by classical nucleation theory

    NASA Astrophysics Data System (ADS)

    Kaufmann, Lukas; Marcolli, Claudia; Luo, Beiping; Peter, Thomas

    2017-03-01

    Homogeneous nucleation of ice in supercooled water droplets is a stochastic process. In its classical description, the growth of the ice phase requires the emergence of a critical embryo from random fluctuations of water molecules between the water bulk and ice-like clusters, which is associated with overcoming an energy barrier. For heterogeneous ice nucleation on ice-nucleating surfaces both stochastic and deterministic descriptions are in use. Deterministic (singular) descriptions are often favored because the temperature dependence of ice nucleation on a substrate usually dominates the stochastic time dependence, and the ease of representation facilitates the incorporation in climate models. Conversely, classical nucleation theory (CNT) describes heterogeneous ice nucleation as a stochastic process with a reduced energy barrier for the formation of a critical embryo in the presence of an ice-nucleating surface. The energy reduction is conveniently parameterized in terms of a contact angle α between the ice phase immersed in liquid water and the heterogeneous surface. This study investigates various ice-nucleating agents in immersion mode by subjecting them to repeated freezing cycles to elucidate and discriminate the time and temperature dependences of heterogeneous ice nucleation. Freezing rates determined from such refreeze experiments are presented for Hoggar Mountain dust, birch pollen washing water, Arizona test dust (ATD), and also nonadecanol coatings. For the analysis of the experimental data with CNT, we assumed the same active site to be always responsible for freezing. Three different CNT-based parameterizations were used to describe rate coefficients for heterogeneous ice nucleation as a function of temperature, all leading to very similar results: for Hoggar Mountain dust, ATD, and larger nonadecanol-coated water droplets, the experimentally determined increase in freezing rate with decreasing temperature is too shallow to be described properly by CNT using the contact angle α as the only fit parameter. Conversely, birch pollen washing water and small nonadecanol-coated water droplets show temperature dependencies of freezing rates steeper than predicted by all three CNT parameterizations. Good agreement of observations and calculations can be obtained when a pre-factor β is introduced to the rate coefficient as a second fit parameter. Thus, the following microphysical picture emerges: heterogeneous freezing occurs at ice-nucleating sites that need a minimum (critical) surface area to host embryos of critical size to grow into a crystal. Fits based on CNT suggest that the critical active site area is in the range of 10-50 nm2, with the exact value depending on sample, temperature, and CNT-based parameterization. Two fitting parameters are needed to characterize individual active sites. The contact angle α lowers the energy barrier that has to be overcome to form the critical embryo at the site compared to the homogeneous case where the critical embryo develops in the volume of water. The pre-factor β is needed to adjust the calculated slope of freezing rate increase with temperature decrease. When this slope is steep, this can be interpreted as a high frequency of nucleation attempts, so that nucleation occurs immediately when the temperature is low enough for the active site to accommodate a critical embryo. This is the case for active sites of birch pollen washing water and for small droplets coated with nonadecanol. If the pre-factor is low, the frequency of nucleation attempts is low and the increase in freezing rate with decreasing temperature is shallow. This is the case for Hoggar Mountain dust, the large droplets coated with nonadecanol, and ATD. Various hypotheses why the value of the pre-factor depends on the nature of the active sites are discussed.

  13. Determinants for successful marketing authorisation of orphan medicinal products in the EU.

    PubMed

    Putzeist, Michelle; Heemstra, Harald E; Garcia, Jordi Llinares; Mantel-Teeuwisse, Aukje K; Gispen-De Wied, Christine C; Hoes, Arno W; Leufkens, Hubert G M

    2012-04-01

    In 2010, the European Regulation for Orphan Medicinal Products (OMPs) was in force for ten years. In this study we assessed possible determinants of applications for OMPs in the EU since 2000 that are associated with a successful marketing authorisation. Our analysis shows that clinical trial characteristics such as demonstrating convincing evidence of a beneficial effect on the primary endpoint, the selection of a clinically relevant endpoint, providing RCT data as pivotal study evidence and the submission of sound dose finding data are critical success factors. In addition, high medical need seems to counterweigh uncertainties about the scientific evidence in the benefit-risk assessment of OMPs. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. [Inconsistencies between building regulations in force in Italy for indoor environment and wellness factors].

    PubMed

    Faggioli, A; Capasso, L

    2015-01-01

    Indoor environment is one of major health determinants, and the regulations that set the sanitary requirements are of primary importance for the protection of public health. The authors analyse the critical aspects of the complex Italian regulatory system, starting from the EU regulations, through national and regional laws, and finally the municipal regulations. They underline the need for more uniformity and clarity in the determination of health standards, as well as for a simplification of the existing legislation. Moreover, they highlight the importance of controlling and monitoring indoor environment, currently almost completely absent in Italy due to the effects of the regulatory changes of the latest years.

  15. Travelling wave resonators fabricated with low-loss hydrogenated amorphous silicon

    NASA Astrophysics Data System (ADS)

    Lipka, Timo; Amthor, Julia; Trieu, Hoc Khiem; Müller, Jörg

    2013-05-01

    Low-loss hydrogenated amorphous silicon is employed for the fabrication of various planar integrated travelling wave resonators. Microring, racetrack, and disk resonators of different dimensions were fabricated with CMOS-compatible processes and systematically investigated. The key properties of notch filter ring resonators as extinction ratio, Q-factor, free spectral range, and the group refractive index were determined for resonators of varying radius, thereby achieving critically coupled photonic systems with high extinction ratios of about 20 dB for both polarizations. Racetrack resonators that are arranged in add/drop configuration and high quality factor microdisk resonators were optically characterized, with the microdisks exhibiting Q-factors of greater than 100000. Four-channel add/drop wavelength-division multiplexing filters that are based on cascaded racetrack resonators are studied. The design, the fabrication, and the optical characterization are presented.

  16. Enhanced uridine 5'-monophosphate production by whole cell of Saccharomyces cerevisiae through rational redistribution of metabolic flux.

    PubMed

    Liu, Dong; Chen, Yong; Li, An; Xie, Jingjing; Xiong, Jian; Bai, Jianxin; Chen, Xiaochun; Niu, Huanqing; Zhou, Tao; Ying, Hanjie

    2012-06-01

    A whole-cell biocatalytic process for uridine 5'-monophosphate (UMP) production from orotic acid by Saccharomyces cerevisiae was developed. To rationally redistribute the metabolic flux between glycolysis and pentose phosphate pathway, statistical methods were employed first to find out the critical factors in the process. NaH(2)PO(4), MgCl(2) and pH were found to be the important factors affecting UMP production significantly. The levels of these three factors required for the maximum production of UMP were determined: NaH(2)PO(4) 22.1 g/L; MgCl(2) 2.55 g/L; pH 8.15. An enhancement of UMP production from 6.12 to 8.13 g/L was achieved. A significant redistribution of metabolic fluxes was observed and the underlying mechanism was discussed.

  17. Protein construct storage: Bayesian variable selection and prediction with mixtures.

    PubMed

    Clyde, M A; Parmigiani, G

    1998-07-01

    Determining optimal conditions for protein storage while maintaining a high level of protein activity is an important question in pharmaceutical research. A designed experiment based on a space-filling design was conducted to understand the effects of factors affecting protein storage and to establish optimal storage conditions. Different model-selection strategies to identify important factors may lead to very different answers about optimal conditions. Uncertainty about which factors are important, or model uncertainty, can be a critical issue in decision-making. We use Bayesian variable selection methods for linear models to identify important variables in the protein storage data, while accounting for model uncertainty. We also use the Bayesian framework to build predictions based on a large family of models, rather than an individual model, and to evaluate the probability that certain candidate storage conditions are optimal.

  18. Structure of nerve growth factor complexed with the shared neurotrophin receptor p75.

    PubMed

    He, Xiao-Lin; Garcia, K Christopher

    2004-05-07

    Neurotrophins are secreted growth factors critical for the development and maintenance of the vertebrate nervous system. Neurotrophins activate two types of cell surface receptors, the Trk receptor tyrosine kinases and the shared p75 neurotrophin receptor. We have determined the 2.4 A crystal structure of the prototypic neurotrophin, nerve growth factor (NGF), complexed with the extracellular domain of p75. Surprisingly, the complex is composed of an NGF homodimer asymmetrically bound to a single p75. p75 binds along the homodimeric interface of NGF, which disables NGF's symmetry-related second p75 binding site through an allosteric conformational change. Thus, neurotrophin signaling through p75 may occur by disassembly of p75 dimers and assembly of asymmetric 2:1 neurotrophin/p75 complexes, which could potentially engage a Trk receptor to form a trimolecular signaling complex.

  19. Hydrolytic stability of biomolecules at high temperatures and its implication for life at 250 °C

    NASA Astrophysics Data System (ADS)

    White, Robert H.

    1984-08-01

    The upper temperature at which a living system can exist is limited by the hydrolytic breakdown rate of its chemical constituents. The peptide bonds of proteins, the phosphodiester and N-glycosyl bonds in RNA and DNA, and the pyrophosphate and N-glycosyl bonds in nucleotides such as ATP and NAD are among the more important bonds that will undergo hydrolysis. The decomposition of biomolecules via non-hydrolytic pathways such as decarboxylations and dehydrations may also be critical factors in determining this upper temperature limit. Baross and Deming1 recently reported `black smoker' bacteria, which they isolated from deep-sea hydrothermal vents, growing at 250 °C. Here I have attempted to establish the rates for the hydrolysis and/or decomposition of critical biomolecules to determine their ability to exist at this temperature. My results clearly indicate that if these organisms exist, and if their metabolic reactions occur in an aqueous environment, they could not survive at this temperature if they were composed of biomolecules such as proteins and nucleic acids, due to the very rapid rate of decomposition of such molecules.

  20. Clinical review: Ethics and end-of-life care for critically ill patients in China

    PubMed Central

    2013-01-01

    Critical care medicine in China has made great advances in recent decades. This has led to an unavoidable issue: end-of-life ethics. With advances in medical technology and therapeutics allowing the seemingly limitless maintenance of life, the exact time of death of an individual patient is often determined by the decision to limit life support. How to care for patients at the end of life is not only a medical problem but also a social, ethical, and legal issue. A lot of factors, besides culture, come into play in determining a person’s ethical attitudes or behaviors, such as experience, education, religion, individual attributes, and economic considerations. Chinese doctors face ethical problems similar to those of their Western counterparts; however, since Chinese society is different from that of Western countries in cultural traditions, customs, religious beliefs, and ethnic backgrounds, there is a great difference between China and the Western world in regard to ethics at the end of life, and there is also a huge controversy within China. PMID:24313980

  1. Using the critical incident survey to assess hospital service quality.

    PubMed

    Longo, B; Connor, G; Barnhart, T

    1993-01-01

    This survey was designed to determine "standards of excellence" in hospital services as defined by (a) former patients, (b) physicians, (c) hospital employees, and (d) corporate insurance subscribers. One hundred forty-seven (147) patients, 188 employees, and 20 corporate subscribers were interviewed by telephone, and 52 physicians were interviewed in their offices. The interview consisted of a single question: "Can you think of a time when, as a patient/employee/employer/physician, you had a particularly satisfying or dissatisfying experience with a local hospital?" Reported incidents were reviewed, and 239 "critical incidents" were identified. These incidents were classified into 12 descriptive categories relating to the underlying factors in the incident reports. Six focus groups were later held with participants segregated by the population pool they represented. These groups were asked to develop definitions of "excellence" in hospital service quality and standards for service which would "exceed expectations." The focus groups created 122 standards of excellence, which were classified into 43 categories. Overall, the largest percentages of corporate, physician, and employee critical incidents were classified as "Administrative Policy" issues. Patients most often reported "Nurturing" incidents as critical to their perceptions of hospital service quality.

  2. Construct validity of the Health Science Reasoning Test.

    PubMed

    Huhn, Karen; Black, Lisa; Jensen, Gail M; Deutsch, Judith E

    2011-01-01

    The aim of this study was to evaluate the construct validity of the Health Science Reasoning Test (HSRT) by determining if the test could discriminate between expert and novice physical therapists' critical-thinking skills. Experts identified from a random list of certified clinical specialists and students in the first year of their physical therapy education from two physical therapy programs completed the HSRT. Experts (n = 73) had a higher total HSRT score (mean 24.06, SD 3.92) than the novices (n = 79) (mean 22.49, SD 3.2), with the difference being statistically significant t (148) = 2.67, p = 0.008. The HSRT total score discriminated between expert and novice critical-thinking skills, therefore establishing construct validity. To our knowledge, this is the first study to compare expert and novice performance on a standardized test. The opportunity to have a tool that provides evidence of students' critical thinking skills could be helpful for educators and students. The test results could aid in identifying areas of students' strengths and weaknesses, thereby enabling targeted remediation to improve critical thinking skills, which are key factors in clinical reasoning, a necessary skill for effective physical therapy practice.

  3. Higher Plasma Pyridoxal Phosphate Is Associated with Increased Antioxidant Enzyme Activities in Critically Ill Surgical Patients

    PubMed Central

    Cheng, Chien-Hsiang; Huang, Shih-Chien; Chiang, Ting-Yu; Wong, Yueching

    2013-01-01

    Critically ill patients experience severe stress, inflammation and clinical conditions which may increase the utilization and metabolic turnover of vitamin B-6 and may further increase their oxidative stress and compromise their antioxidant capacity. This study was conducted to examine the relationship between vitamin B-6 status (plasma and erythrocyte PLP) oxidative stress, and antioxidant capacities in critically ill surgical patients. Thirty-seven patients in surgical intensive care unit of Taichung Veterans General Hospital, Taiwan, were enrolled. The levels of plasma and erythrocyte PLP, serum malondialdehyde, total antioxidant capacity, and antioxidant enzyme activities (i.e., superoxide dismutase (SOD), glutathione S-transferase, and glutathione peroxidase) were determined on the 1st and 7th days of admission. Plasma PLP was positively associated with the mean SOD activity level on day 1 (r = 0.42, P < 0.05), day 7 (r = 0.37, P < 0.05), and on changes (Δ (day 7 − day 1)) (r = 0.56, P < 0.01) after adjusting for age, gender, and plasma C-reactive protein concentration. Higher plasma PLP could be an important contributing factor in the elevation of antioxidant enzyme activity in critically ill surgical patients. PMID:23819116

  4. Factor Analyses and Score Validity of the Family Emotional Involvement and Criticism Scale in an Adolescent Sample

    ERIC Educational Resources Information Center

    Nelis, Sharon M.; Rae, Gordon; Liddell, Christine

    2006-01-01

    The factor structure of the Family Emotional Involvement and Criticism Scale (FEICS) is tested in a sample of Irish adolescents. Participants were 661 adolescents with a mean age of 15.9 years (SD = 1.26). Interpretation of both the exploratory and confirmatory factor analysis of the FEICS show support for the two-factor structure of the FEICS…

  5. Reducing measurement uncertainty drives the use of multiple technologies for supporting metrology

    NASA Astrophysics Data System (ADS)

    Banke, Bill, Jr.; Archie, Charles N.; Sendelbach, Matthew; Robert, Jim; Slinkman, James A.; Kaszuba, Phil; Kontra, Rick; DeVries, Mick; Solecky, Eric P.

    2004-05-01

    Perhaps never before in semiconductor microlithography has there been such an interest in the accuracy of measurement. This interest places new demands on our in-line metrology systems as well as the supporting metrology for verification. This also puts a burden on the users and suppliers of new measurement tools, which both challenge and complement existing manufacturing metrology. The metrology community needs to respond to these challenges by using new methods to assess the fab metrologies. An important part of this assessment process is the ability to obtain accepted reference measurements as a way of determining the accuracy and Total Measurement Uncertainty (TMU) of an in-line critical dimension (CD). In this paper, CD can mean any critical dimension including, for example, such measures as feature height or sidewall angle. This paper describes the trade-offs of in-line metrology systems as well as the limitations of Reference Measurement Systems (RMS). Many factors influence each application such as feature shape, material properties, proximity, sampling, and critical dimension. These factors, along with the metrology probe size, interaction volume, and probe type such as e-beam, optical beam, and mechanical probe, are considered. As the size of features shrinks below 100nm some of the stalwarts of reference metrology come into question, such as the electrically determined transistor gate length. The concept of the RMS is expanded to show how multiple metrologies are needed to achieve the right balance of accuracy and sampling. This is also demonstrated for manufacturing metrology. Various comparisons of CDSEM, scatterometry, AFM, cross section SEM, electrically determined CDs, and TEM are shown. An example is given which demonstrates the importance in obtaining TMU by balancing accuracy and precision for selecting manufacturing measurement strategy and optimizing manufacturing metrology. It is also demonstrated how the necessary supporting metrology will bring together formerly unlinked technology fields requiring new measurement science. The emphasis on accuracy will increase the importance and role of NIST and similar metrology organizations in supporting the semiconductor industry in this effort.

  6. Thermodynamic Cconstraints on Coupled Carbonate-Pyrite Weathering Dynamics and Carbon Fluxes

    NASA Astrophysics Data System (ADS)

    Winnick, M.; Maher, K.

    2017-12-01

    Chemical weathering within the critical zone regulates global biogeochemical cycles, atmospheric composition, and the supply of key nutrients to terrestrial and aquatic ecosystems. Recent studies suggest that thermodynamic limits on solute production act as a first-order control on global chemical weathering rates; however, few studies have addressed the factors that set these thermodynamic limits in natural systems. In this presentation, we investigate the effects of soil CO2 concentrations and pyrite oxidation rates on carbonate dissolution and associated carbon fluxes in the East River watershed in Colorado, using concentration-discharge relationships and thermodynamic constraints. Within the shallow subsurface, soil respiration rates and moisture content determine the extent of carbonic acid-promoted carbonate dissolution through their modulation of soil pCO2 and the balance of open- v. closed-system weathering processes. At greater depths, pyrite oxidation generates sulfuric acid, which alters the approach to equilibrium of infiltrating waters. Through comparisons of concentration-discharge data and reactive transport model simulations, we explore the conditions that determine whether sulfuric acid reacts to dissolve additional carbonate mineral or instead reacts with alkalinity already in solution - the balance of which determines watershed carbon flux budgets. Our study highlights the importance of interactions between the chemical structure of the critical zone and the hydrologic regulation of flowpaths in determining concentration-discharge relationships and overall carbon fluxes.

  7. Critical Factors Explaining the Leadership Performance of High-Performing Principals

    ERIC Educational Resources Information Center

    Hutton, Disraeli M.

    2018-01-01

    The study explored critical factors that explain leadership performance of high-performing principals and examined the relationship between these factors based on the ratings of school constituents in the public school system. The principal component analysis with the use of Varimax Rotation revealed that four components explain 51.1% of the…

  8. Evidence for deep sub-surface flow routing in forested upland Wales: implications for contaminant transport and stream flow generation

    NASA Astrophysics Data System (ADS)

    Bridcut, E. E.; McNish, J.; Harriman, R.

    2004-06-01

    Critical Load (CL) methodology is currently used throughout Europe to assess the risks of ecological damage due to sulphur and nitrogen emissions. Critical acid neutralising capacity (ANCCRIT) is used in CL estimates for freshwater systems as a surrogate for biological damage. Although UK CL maps presently use an ANC value of 0 μeq l-1, this value has been based largely on Norwegian lake studies, in which brown trout is chosen as a representative indicator organism. In this study, an ANC value specific for brown trout in Scottish streams was determined and issues were addressed such as salmon and trout sensitivity in streams, episodicity, afforestation and complicating factors such as dissolved organic carbon (DOC) and labile aluminium (Al-L). Catchments with significant forest cover were selected to provide fishless sites and to provide catchment comparisons in unpolluted areas. Chemical factors were the primary determinant with land use a secondary determinant of the distribution of salmonid populations at the twenty-six study sites. ANC explained more variance in brown trout density than pH. The most significant index of episodicity was percent of time spent below an ANC of 0 μeq l-1. An ANCCRIT value of 39 μeq l-1 was obtained based on a 50% probability of brown trout occurrence. The use of this revised ANCCRIT value in the CL equation improved the relationship between trout status and exceedance of CLs. Uncertainties associated with variations in Al-L at any fixed ANCCRIT, particularly within forested catchments, and the role of DOC in modifying the toxicity of Al-L are discussed.

  9. Experimental determinations of the eigenmodes for composite bars made with carbon and Kevlar-carbon fibers

    NASA Astrophysics Data System (ADS)

    Miriţoiu, C. M.; Stănescu, M. M.; Burada, C. O.; Bolcu, D.; Roşca, V.

    2015-11-01

    For modal identification, the single-point excitation method has been widely used in modal tests and it consists in applying a force in a given point and recording the vibratory structure response in all interest points, including the excitation point. There will be presented the experimental recordings for the studied bars (with Kevlar-carbon or carbon fibers), the frequency response function in Cartesian and polar coordinates. By using the frequency response functions we determine the eigenparameters for each bar. We present the final panel of the eigenmodes (with the damping factors, eigenfrequencies and critical damping) for each considered bar. Using the eigenfrequency of the first determined eigenmode, the bars stiffness has been determined. The presented bars can be used in practical engineering for: car or bus body parts, planes body parts, bullet-proof vests, reinforcements for sandwich beams, and so on.

  10. Factors influencing patient compliance with therapeutic regimens in chronic heart failure: A critical incident technique analysis.

    PubMed

    Strömberg, A; Broström, A; Dahlström, U; Fridlund, B

    1999-01-01

    The aim of this study was to identify factors influencing compliance with prescribed treatment in patients with chronic heart failure. A qualitative design with a critical incident technique was used. Incidents were collected through interviews with 25 patients with heart failure strategically selected from a primary health care clinic, a medical ward, and a specialist clinic. Two hundred sixty critical incidents were identified in the interviews and 2 main areas emerged in the analysis: inward factors and outward factors. The inward factors described how compliance was influenced by the personality of the patient, the disease, and the treatment. The outward factors described how compliance was influenced by social activities, social relationships, and health care professionals. By identifying the inward and outward factors influencing patients with chronic heart failure, health care professionals can assess whether intervention is needed to increase compliance.

  11. Why language matters: insights and challenges in applying a social determination of health approach in a North-South collaborative research program.

    PubMed

    Spiegel, Jerry M; Breilh, Jaime; Yassi, Annalee

    2015-02-27

    Focus on "social determinants of health" provides a welcome alternative to the bio-medical illness paradigm. However, the tendency to concentrate on the influence of "risk factors" related to living and working conditions of individuals, rather than to more broadly examine dynamics of the social processes that affect population health, has triggered critical reaction not only from the Global North but especially from voices the Global South where there is a long history of addressing questions of health equity. In this article, we elaborate on how focusing instead on the language of "social determination of health" has prompted us to attempt to apply a more equity-sensitive approaches to research and related policy and praxis. In this debate, we briefly explore the epistemological and historical roots of epidemiological approaches to health and health equity that have emerged in Latin America to consider its relevance to global discourse. In this region marked by pronounced inequity, context-sensitive concepts such as "collective health" and "critical epidemiology" have been prominent, albeit with limited acknowledgement by the Global North. We illustrate our attempts to apply a social determination approach (and the "4 S" elements of bio-Security, Sovereignty, Solidarity and Sustainability) in five projects within our research collaboration linking researchers and knowledge users in Ecuador and Canada, in diverse settings (health of healthcare workers; food systems; antibiotic resistance; vector borne disease [dengue]; and social circus with street youth). We argue that the language of social determinants lends itself to research that is more reductionist and beckons the development of different skills than would be applied when adopting the language of social determination. We conclude that this language leads to more direct analysis of the systemic factors that drive, promote and reinforce disparities, while at the same time directly considering the emancipatory forces capable of countering negative health impacts. It follows that "reverse innovation" must not only recognize practical solutions being developed in low and middle income countries, but must also build on the strengths of the theoretical-methodological reasoning that has emerged in the South.

  12. [Neurobiological determinism: questionable inferences on human freedom of choice and forensic criminal responsibility].

    PubMed

    Urbaniok, F; Hardegger, J; Rossegger, A; Endrass, J

    2006-08-01

    Several authors argue that criminal behavior is generally caused by neurobiological deficits. Based on this neurobiological perspective of assumed causality, the concept of free will is questioned, and the theory of neurobiological determinism of all human behavior is put forward, thus maintaining that human beings are not responsible for their actions, and consequently the principle of guilt should be given up in criminal law. In this context the controversial debate on determinism and indeterminism, which has been held for centuries, has flared up anew, especially within the science of criminal law. When critically examining the current state of research, it becomes apparent that the results do not support the existence of a universally valid neurobiological causality of criminal behavior, nor a theory of an absolute neurobiological determinism. Neither is complete determination of all phenomena in the universe--as maintained--the logical conclusion of the principle of causality, nor is it empirically confirmed. Analyzed methodically, it cannot be falsified, and thus, as a theory which cannot be empirically tested, it represents a dogma against which plausible objections can be made. The criticism of the concept of free will, and even more so of human accountability and criminal responsibility, is not put forward in a valid way. The principle of relative determinism--the evaluation of the degree of determinism of personality factors potentially reducing criminal responsibility, which includes concrete observations and analysis of behavior--thus remains a central and cogent approach to the assessment of criminal responsibility. To sum up, the theories proposed by some authors on the complete neurobiological determinism of human behavior, and the subsequent impossibility of individual responsibility and guilt, reveal both methodical misconception and a lack of empirical foundation.

  13. Approaches to rationing antiretroviral treatment: ethical and equity implications.

    PubMed Central

    Bennett, Sara; Chanfreau, Catherine

    2005-01-01

    Despite a growing global commitment to the provision of antiretroviral therapy (ART), its availability is still likely to be less than the need. This imbalance raises ethical dilemmas about who should be granted access to publicly-subsidized ART programmes. This paper reviews the eligibility and targeting criteria used in four case-study countries at different points in the scale-up of ART, with the aim of drawing lessons regarding ethical approaches to rationing. Mexico, Senegal, Thailand and Uganda have each made an explicit policy commitment to provide antiretrovirals to all those in need, but are achieving this goal in steps--beginning with explicit rationing of access to care. Drawing upon the case-studies and experiences elsewhere, categories of explicit rationing criteria have been identified. These include biomedical factors, adherence to treatment, prevention-driven factors, social and economic benefits, financial factors and factors driven by ethical arguments. The initial criteria for determining eligibility are typically clinical criteria and assessment of adherence prospects, followed by a number of other factors. Rationing mechanisms reflect several underlying ethical theories and the ethical underpinnings of explicit rationing criteria should reflect societal values. In order to ensure this alignment, widespread consultation with a variety of stakeholders, and not only policy-makers or physicians, is critical. Without such explicit debate, more rationing will occur implicitly and this may be more inequitable. The effects of rationing mechanisms upon equity are critically dependent upon the implementation processes. As antiretroviral programmes are implemented it is crucial to monitor who gains access to these programmes. PMID:16175829

  14. Factors influencing wood mobilization in Minnesota streams

    USGS Publications Warehouse

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

    2010-01-01

    Natural pieces of wood provide a variety of ecosystem functions in streams including habitat, organic matter retention, increased hyporheic exchange and transient storage, and enhanced hydraulic and geomorphic heterogeneity. Wood mobilization is a critical process in determining the residence time of wood. We documented the characteristics and locations of 865 natural wood pieces (>0.05 m in diameter for a portion >1 m in length) in nine streams along the north shore of Lake Superior in Minnesota. We determined the locations of the pieces again after an overbank stormflow event to determine the factors that influenced mobilization of stationary wood pieces in natural streams. Seven of 11 potential predictor variables were identified with multiple logistic regression as significant to mobilization: burial, effective depth, ratio of piece length to effective stream width (length ratio), bracing, rootwad presence, downstream force ratio, and draft ratio. The final model (P< 0.001, r2 = 0.39) indicated that wood mobilization under natural conditions is a complex function of both mechanical factors (burial, length ratio, bracing, rootwad presence, draft ratio) and hydraulic factors (effective depth, downstream force ratio). If stable pieces are a goal for stream management then features such as partial burial, low effective depth, high length relative to channel width, bracing against other objects (e.g., stream banks, trees, rocks, or larger wood pieces), and rootwads are desirable. Using the model equation from this study, stewards of natural resources can better manage in-stream wood for the benefit of stream ecosystems.

  15. Organizational resilience and enrollment trends of independent, for-profit higher education institutions.

    PubMed

    Frisbie, Kathryn; Converso, Judith

    2016-05-24

    From 2010 to 2012, the for-profit sector of higher education in the United States (otherwise known as career colleges) existed in a turbulent environment, characterized by regulatory, media, and public scrutiny. While virtually all career colleges experienced enrollment declines during this period, by 2012 some colleges were starting to see this trend stabilize or reverse, whereas others did not. The purpose of this study was to determine if the differences in career colleges' enrollment trends could be attributed to organizational resilience. A quantitative correlation study using a multiple regression analysis was conducted to determine the nature of the relationship between organizational resilience and the enrollment fluctuations of 59 career colleges located throughout the United States. The correlation between organizational resilience levels and enrollment fluctuations was fair to moderate and significant, r = 0.40, p < 0.05. A multiple-regression analysis revealed that the model significantly explained the impact of the six organizational resilience factors on enrollment fluctuations, F = 4.15, p < 0.01. The R2 for the model was 0.32, and the adjusted R2 was 0.25. In terms of individual organizational resilience factors, two tested either significantly or moderately significantly: avoidance-skepticism and critical understanding or sensemaking. Recommendations for college leaders include monitoring the level of avoidance to ensure a healthy balance of skepticism regarding new situations and incorporating strategies to help organizational members increase their levels of critical understanding or sensemaking.

  16. Selecting physician leaders for clinical service lines: critical success factors.

    PubMed

    Epstein, Andrew L; Bard, Marc A

    2008-03-01

    Clinical service lines and interdisciplinary centers have emerged as important strategic programs within academic health centers (AHCs). Effective physician leadership is significant to their success, but how these leaders are chosen has not been well studied. The authors conducted a study to identify current models for selecting the physician leaders of clinical service lines, determine critical success factors, and learn how the search process affected service line performance. In 2003 and 2004, the authors interviewed clinical and executive personnel involved in 14 programs to establish, or consider establishing, heart or cancer service lines, at 13 AHCs. The responses were coded to identify and analyze trends and themes. The key findings of the survey were (1) the goals and expectations that AHCs set for their service line leaders vary greatly, depending on both the strategic purpose of the service line in the AHC and the service line's stage of development, (2) the matrix organizational structure employed by most AHCs limits the leader's authority over necessary resources, and calls forth a variety of compensating strategies if the service line is to succeed, (3) the AHCs studied used relatively informal processes to identify, evaluate, and select service line leaders, and (4) the leader's job is vitally shaped by the AHC's strategic, structural, and political context, and selection criteria should be determined accordingly. Institutions should be explicit about the strategic purpose and stage of development of their clinical service lines and be clear about their expectations and requirements in hiring service line leaders.

  17. A Decision Process for Determining Whether to Conduct Responder Health Research Following Disasters

    PubMed Central

    Decker, John A.; Kiefer, Max; Reissman, Dori B.; Funk, Renée; Halpin, John; Bernard, Bruce; Ehrenberg, Richard L.; Schuler, Christine R.; Whelan, Elizabeth; Myers, Kyle; Howard, John

    2015-01-01

    Background Disasters often set the stage for scientific inquiry within the field of occupational safety and health. This is especially true when the long-term consequences of exposures associated with a particular disaster are unclear. However, a responder research study can be costly and difficult to design, and researchers must consider whether the proposed study will produce useful, reliable results and is a prudent public health investment. Methods Senior NIOSH scientists, experienced with disaster response and representing the disciplines of epidemiology, occupational medicine and psychiatry, and industrial hygiene, were convened at the request of the NIOSH Director to develop a decision process to help determine when to conduct responder health research following disasters. Results The decision process can be broken down into various components, including scientific rationale that should be formally recognized as critical to efficiently and effectively determine whether a research study is warranted. The scientific rationale includes certain controlling or “gatekeeper” factors that should be present to proceed with research. Providing the foundation for responder disaster research also requires strategizing before an event occurs, so that critical baseline and comparison data can be collected. Conclusions The recommended framework should ensure that research that is most needed and justified will be identified and prioritized. PMID:23716371

  18. The effect of nutritional status and myogenic satellite cell age on turkey satellite cell proliferation, differentiation, and expression of myogenic transcriptional regulatory factors and heparan sulfate proteoglycans syndecan-4 and glypican-1.

    PubMed

    Harthan, Laura B; McFarland, Douglas C; Velleman, Sandra G

    2014-01-01

    Posthatch satellite cell mitotic activity is a critical component of muscle development and growth. Satellite cells are myogenic stem cells that can be induced by nutrition to follow other cellular developmental pathways, and whose mitotic activity declines with age. The objective of the current study was to determine the effect of restricting protein synthesis on the proliferation and differentiation, expression of myogenic transcriptional regulatory factors myogenic determination factor 1, myogenin, and myogenic regulatory factor 4, and expression of the heparan sulfate proteoglycans syndecan-4 and glypican-1 in satellite cells isolated from 1-d-, 7-wk-, and 16-wk-old turkey pectoralis major muscle (1 d, 7 wk, and 16 wk cells, respectively) by using variable concentrations of Met and Cys. Four Met concentrations-30 (control), 7.5, 3, or 0 mg/L with 3.2 mg/L of Cys per 1 mg/L of Met-were used for culture of satellite cells to determine the effect of nutrition and age on satellite cell behavior during proliferation and differentiation. Proliferation was reduced by lower Met and Cys concentrations in all ages at 96 h of proliferation. Differentiation was increased in the 1 d Met-restricted cells, whereas the 7 wk cells treated with 3 mg/L of Met had decreased differentiation. Reduced Met and Cys levels from the control did not significantly affect the 16 wk cells at 72 h of differentiation. However, medium with no Met or Cys suppressed differentiation at all ages. The expression of myogenic determination factor 1, myogenin, myogenic regulatory factor 4, syndecan-4, and glypican-1 was differentially affected by age and Met or Cys treatment. These data demonstrate the age-specific manner in which turkey pectoralis major muscle satellite cells respond to nutritional availability and the importance of defining optimal nutrition to maximize satellite cell proliferation and differentiation for subsequent muscle mass accretion.

  19. Assessing field vulnerability to phosphorus loss in Beijing agricultural area using Revised Field Phosphorus Ranking Scheme.

    PubMed

    Li, Qi; Chen, Li-ding; Qi, Xin; Zhang, Xin-yu; Ma, Yan; Fu, Bo-jie

    2007-01-01

    Guanting Reservoir, one of the drinking water supply sources of Beijing, suffers from water eutrophication. It is mainly supplied by Guishui River. Thus, to investigate the reasons of phosphorus (P) loss and improve the P management strategies in Guishui River watershed are important for the safety of drinking water in this region. In this study, a Revised Field P Ranking Scheme (PRS) was developed to reflect the field vulnerability of P loss at the field scale based on the Field PRS. In this new scheme, six factors are included, and each one was assigned a relative weight and a determination method. The affecting factors were classified into transport factors and source factors, and, the standards of environmental quality on surface water and soil erosion classification and degradation of the China were used in this scheme. By the new scheme, thirty-four fields in the Guishui River were categorized as "low", "medium" or "high" potential for P loss into the runoff. The results showed that the P loss risks of orchard and vegetable fields were higher than that of corn and soybean fields. The source factors were the main factors to affect P loss from the study area. In the study area, controlling P input and improving P usage efficiency are critical to decrease P loss. Based on the results, it was suggested that more attention should be paid on the fields of vegetable and orchard since they have extremely high usage rate of P and high soil test of P. Compared with P surplus by field measurements, the Revised Field PRS was more suitable for reflecting the characteristics of fields, and had higher potential capacity to identify critical source areas of P loss than PRS.

  20. Implications of High Temperature and Elevated CO2 on Flowering Time in Plants

    PubMed Central

    Jagadish, S. V. Krishna; Bahuguna, Rajeev N.; Djanaguiraman, Maduraimuthu; Gamuyao, Rico; Prasad, P. V. Vara; Craufurd, Peter Q.

    2016-01-01

    Flowering is a crucial determinant for plant reproductive success and seed-set. Increasing temperature and elevated carbon-dioxide (e[CO2]) are key climate change factors that could affect plant fitness and flowering related events. Addressing the effect of these environmental factors on flowering events such as time of day of anthesis (TOA) and flowering time (duration from germination till flowering) is critical to understand the adaptation of plants/crops to changing climate and is the major aim of this review. Increasing ambient temperature is the major climatic factor that advances flowering time in crops and other plants, with a modest effect of e[CO2].Integrated environmental stimuli such as photoperiod, temperature and e[CO2] regulating flowering time is discussed. The critical role of plant tissue temperature influencing TOA is highlighted and crop models need to substitute ambient air temperature with canopy or floral tissue temperature to improve predictions. A complex signaling network of flowering regulation with change in ambient temperature involving different transcription factors (PIF4, PIF5), flowering suppressors (HvODDSOC2, SVP, FLC) and autonomous pathway (FCA, FVE) genes, mainly from Arabidopsis, provides a promising avenue to improve our understanding of the dynamics of flowering time under changing climate. Elevated CO2 mediated changes in tissue sugar status and a direct [CO2]-driven regulatory pathway involving a key flowering gene, MOTHER OF FT AND TFL1 (MFT), are emerging evidence for the role of e[CO2] in flowering time regulation. PMID:27446143

  1. Factors associated with Iowa rural hospitals' decision to convert to critical access hospital status.

    PubMed

    Li, Pengxiang; Ward, Marcia M; Schneider, John E

    2009-01-01

    The Balanced Budget Act (BBA) of 1997 allowed some rural hospitals meeting certain requirements to convert to Critical Access Hospitals (CAHs) and changed their Medicare reimbursement from prospective to cost-based. Some subsequent CAH-related laws reduced restrictions and increased payments, and the number of CAHs grew rapidly. To examine factors related to hospitals' decisions to convert and time to CAH conversion. Eighty-nine rural hospitals in Iowa were characterized and observed from 1998 to 2005. Cox proportional hazards models were used to identify the determinants of time to CAH conversion. T-test and one-covariate Cox regression indicated that, in 1998, Iowa rural hospitals with more staffed beds, discharges, and acute inpatient days, higher operating margin, lower skilled swing bed days relative to acute days, and located in relatively high density counties were more likely to convert later or not convert before 2006. Multiple Cox regression with baseline covariates indicated that lower number of discharges and average length of stay (ALOS) were significant after controlling all other covariates. Iowa rural hospitals' decisions regarding CAH conversion were influenced by hospital size, financial condition, skilled swing bed days relative to acute days, length of stay, proportion of Medicare acute days, and geographic factors. Although financial concerns are often cited in surveys as the main reason for conversion, lower number of discharges and ALOS are the most prominent factors affecting rural hospitals' decision on when to convert.

  2. From equity to power: Critical Success Factors for Twinning between midwives, a Delphi study.

    PubMed

    Cadée, Franka; Nieuwenhuijze, Marianne J; Lagro-Janssen, Antoine L M; de Vries, Raymond

    2018-02-28

    To gain consensus for Critical Success Factors associated with Twinning in Midwifery. International publications identify midwifery as important for improving maternity care worldwide. Midwifery is a team effort where midwives play a key role. Yet their power to take on this role is often lacking. Twinning has garnered potential to develop power in professionals, however, its success varies because implementation is not always optimal. Critical Success Factors have demonstrated positive results in the managerial context and can be helpful to build effective Twinning relationships. We approached 56 midwife Twinning experts from 19 countries to participate in three Delphi rounds between 2016 - 2017. In round 1, experts gave input through an open ended questionnaire and this was analysed to formulate Critical Success Factors statements that were scored on a 1-7 Likert scale aiming to gain consensus in rounds 2 and 3. These statements were operationalized for practical use such as a check list in planning, monitoring and evaluation in the field. Thirty-three experts from 14 countries took part in all three Delphi rounds, producing 58 initial statements. This resulted in 25 Critical Success Factors covering issues of management, communication, commitment and values, most focus on equity. The Critical Success Factors formulated represent the necessary ingredients for successful Twinning by providing a practical implementation framework and promote further research into the effect of Twinning. Findings show that making equity explicit in Twinning may contribute towards the power of midwives to take on their identified key role. © 2018 The Authors. Journal of Advanced Nursing Published by John Wiley & Sons Ltd.

  3. Under Pressure: Controlling Factors Faced by Classroom Literacy Teachers as They Work through a Professional Development Program

    ERIC Educational Resources Information Center

    Wallace, Faith H.

    2006-01-01

    This critical constructivist inquiry was designed to understand controlling factors faced by classroom literacy teachers involved in a professional development program. Two guiding questions framed this critical inquiry: (1) how can I describe controlling factors faced by teachers in their respective school cultures; and (2) what is the resultant…

  4. Lake trout spawning habitat in the Great Lakes - a review of current knowledge

    USGS Publications Warehouse

    Marsden, J. Ellen; Casselman, John M.; Edsall, Thomas A.; Elliott, Robert F.; Fitzsimons, John D.; Horns, William H.; Manny, Bruce A.; McAughey, Scott C.; Sly, Peter G.; Swanson, Bruce L.

    1995-01-01

    We review existing information on lake trout spawning habitat, which might indicate whether habitat is now a limiting factor in lake trout reproductive success. Lake trout spawning habitat quality is defined by the presence or absence of olfactory cues for homing, reef location with respect to the shoreline, water depth, proximity to nursery areas, reef size, contour, substrate size and shape, depth of interstitial spaces, water temperature at spawning time, water quality in interstitial spaces, and the presence of egg and fry predators. Data on factors which attracted native spawners to spawning reefs are lacking, due to the absence of historic data on egg deposition. No direct evidence of egg deposition has been collected from sites deeper than 18 m. Interstitial space and, therefore, substrate size and shape, appear to be critical for both site selection by adults and protection of eggs and fry. Water quality is clearly important for egg incubation, but the critical parameters which define water quality have not yet been well determined in the field. Exposure to wave energy, dictated in part by reef location, may maintain high water quality but may also damage or dislodge eggs. The importance of olfactory cues, water temperature, and proximity to nursery habitat to spawning trout is unclear. Limited data suggest that egg and fry predators, particularly exotic species, may critically affect fry production and survival. Although availability of physical spawning habitat is probably not limiting lake trout reproduction, changes in water quality and species composition may negatively affect early life stages. This review of habitat factors that affect early life stages of lake trout suggests several priorities for research and management.

  5. Radiation Dose-Volume Effects and the Penile Bulb

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

    Roach, Mack, E-mail: mroach@radonc.ucsf.ed; Nam, Jiho; Gagliardi, Giovanna

    2010-03-01

    The dose, volume, and clinical outcome data for penile bulb are reviewed for patients treated with external-beam radiotherapy. Most, but not all, studies find an association between impotence and dosimetric parameters (e.g., threshold doses) and clinical factors (e.g., age, comorbid diseases). According to the data available, it is prudent to keep the mean dose to 95% of the penile bulb volume to <50 Gy. It may also be prudent to limit the D70 and D90 to 70 Gy and 50 Gy, respectively, but coverage of the planning target volume should not be compromised. It is acknowledged that the penile bulbmore » may not be the critical component of the erectile apparatus, but it seems to be a surrogate for yet to be determined structure(s) critical for erectile function for at least some techniques.« less

  6. Probabilistic Analysis of Gas Turbine Field Performance

    NASA Technical Reports Server (NTRS)

    Gorla, Rama S. R.; Pai, Shantaram S.; Rusick, Jeffrey J.

    2002-01-01

    A gas turbine thermodynamic cycle was computationally simulated and probabilistically evaluated in view of the several uncertainties in the performance parameters, which are indices of gas turbine health. Cumulative distribution functions and sensitivity factors were computed for the overall thermal efficiency and net specific power output due to the thermodynamic random variables. These results can be used to quickly identify the most critical design variables in order to optimize the design, enhance performance, increase system availability and make it cost effective. The analysis leads to the selection of the appropriate measurements to be used in the gas turbine health determination and to the identification of both the most critical measurements and parameters. Probabilistic analysis aims at unifying and improving the control and health monitoring of gas turbine aero-engines by increasing the quality and quantity of information available about the engine's health and performance.

  7. Luchando y logrando/struggling and achieving: Resilience of Latina/o math and science teacher candidates at California Hispanic-Serving Institutions: A critical race perspective

    NASA Astrophysics Data System (ADS)

    Gonzalez, Laura

    Latin math and science students represent a resilient, determined, and encouraging group of high achievers. This qualitative study presents the narratives of 10 Latin science and math teacher candidates currently attending Hispanic-Serving Institutions in California. Semi structured, in-depth interviews were conducted, where participants shared the challenges they experienced and the factors that contributed to their resilience. The Connor Davidson Resilience Scale CD-RISC was used to present resilience measures for each participant. This score is compared to a group of college students throughout the nation. The findings provide insight into the critical need for universities to examine institutional practices and efforts to support these high achievers who have already beaten tremendous odds by entering the halls of higher education.

  8. Viewpoint: methanol poisoning outbreak in Libya: a need for policy reforms.

    PubMed

    Taleb, Ziyad Ben; Bahelah, Raed

    2014-11-01

    We address the controversies surrounding a 2013 outbreak of methanol poisoning in Tripoli, Libya. We critically examine and systematically analyze the outbreak to highlight the lessons learned from this disaster and how to act properly to prevent similar outbreaks in future. Many health problems have been directly attributed to drinking alcohol; the type and quality of alcohol determines the detrimental effects. An unregulated and flourishing black market in alcohol is among the factors behind the Libyan tragedy, where approximately 90 deaths and about 1000 hospital admissions were reported. We reviewed gaps in local and regional alcohol policy, and highlighted the issue of illegally produced and home-made alcohol. Collaboration between countries in the region plus critical health and policy reforms in Libya, with emphasis on public health preparedness, can dramatically decrease morbidity and mortality associated with such outbreaks.

  9. Joule-Thomson inversion curves and related coefficients for several simple fluids

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Peller, I. C.; Baron, A. K.

    1972-01-01

    The equations of state (PVT relations) for methane, oxygen, argon, carbon dioxide, carbon monoxide, neon, hydrogen, and helium were used to establish Joule-Thomson inversion curves for each fluid. The principle of corresponding states was applied to the inversion curves, and a generalized inversion curve for fluids with small acentric factors was developed. The quantum fluids (neon, hydrogen, and helium) were excluded from the generalization, but available data for the fluids xenon and krypton were included. The critical isenthalpic Joule-Thomson coefficient mu sub c was determined; and a simplified approximation mu sub c approximates T sub c divided by 6P sub c was found adequate, where T sub c and P sub c are the temperature and pressure at the thermodynamic critical point. The maximum inversion temperatures were obtained from the second virial coefficient (maximum (B/T)).

  10. Monte Carlo Criticality Analysis of Simple Geometrics COntaining Tungsten Rhenium Alloys Engrained with Uranium Dioxide and Uranium Mononitride

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

    Jonathan A. Webb; Indrajit Charit

    2011-08-01

    The critical mass and dimensions of simple geometries containing highly enriched uraniumdioxide (UO2) and uraniummononitride (UN) encapsulated in tungsten-rhenium alloys are determined using MCNP5 criticality calculations. Spheres as well as cylinders with length to radius ratios of 1.82 are computationally built to consist of 60 vol.% fuel and 40 vol.% metal matrix. Within the geometries the uranium is enriched to 93 wt.% uranium-235 and the rhenium content within the metal alloy was modeled over a range of 0 to 30 at.%. The spheres containing UO2 were determined to have a critical radius of 18.29 cm to 19.11 cm and amore » critical mass ranging from 366 kg to 424 kg. The cylinders containing UO2 were found to have a critical radius ranging from 17.07 cm to 17.844 cm with a corresponding critical mass of 406 kg to 471 kg. Spheres engrained with UN were determined to have a critical radius ranging from 14.82 cm to 15.19 cm and a critical mass between 222 kg and 242 kg. Cylinders which were engrained with UN were determined to have a critical radius ranging from 13.811 cm to 14.155 cm with a corresponding critical mass of 245 kg to 267 kg. The critical geometries were also computationally submerged in a neutronaically infinite medium of fresh water to determine the effects of rhenium addition on criticality accidents due to water submersion. The monte carlo analysis demonstrated that rhenium addition of up to 30 at.% can reduce the excess reactivity due to water submersion by up to $5.07 for UO2 fueled cylinders, $3.87 for UO2 fueled spheres and approximately $3.00 for UN fueled spheres and cylinders.« less

  11. Bacterial uptake of antibiotics in model unsaturated systems

    NASA Astrophysics Data System (ADS)

    Zhang, W.; Chen, Z.; Zhang, Y.; Zhao, Z.; Wang, G.; Gao, Y.; Boyd, S. A.; Zhu, D.; Li, H.

    2016-12-01

    Anthropogenic antibiotics are ubiquitously present in the environment due to large uses in human medicine and animal agriculture, and are causing unintended consequence to human and ecosystem health. Bacterial uptake of antibiotics could exert selection pressure on antibiotic resistance development among bacteria population. Therefore, understanding environmental factors controlling bioavailability of antibiotics to bacteria is critical to better assessing exposure risks and developing mitigation strategies. Nonetheless, conventional bioavailability assays are often performed in water-saturated systems that do not represent unsaturated soils where most bacteria live, therefore neglecting soil water as a controlling factor in determining the extent of antibiotic bacterial uptake. Therefore, we propose to study bacterial uptake of antibiotics in model unsaturated systems using GFP-tagged Escherichia coli bioreporter for tetracyclines. Our preliminary studies demonstrated the important role of water content (or water matric potential) in determining the bioavailability of antibiotics, and complex interactions of water potential, tetracycline diffusion, and E. coli growth. Therefore, unsaturated processes are important for understanding antibiotic resistance development and developing mitigation strategies.

  12. Magnitude and distribution of trunk stresses in telecommunications engineers.

    PubMed Central

    Nicholson, A S; David, P R; Sheppard, N J

    1981-01-01

    The incidence of back injuries has been shown to be greater in occupations as heavy manual work than light manual work. To plan a programme aimed at reducing the incidence of back injuries in industry those workers at high risk of incurring handling accidents and back injuries need to be identified and a knowledge of the specific occupational factors causing such injuries sought. This has been achieved for telecommunications engineers using epidemiological and radio pressure pill methodologies. The results verify the correlation between the back injury rates and physical work stresses of different occupational groups. The magnitude and relative frequency of trunk stresses in hazardous tasks has been determined and compared with those with lower incidences of back disorders. The study has confirmed that in examining manual handling hazards in industrial male populations a critical value of truncal stress can be applied and used to determine the safety of occupational factors in relation to their potential causing or contributing to degenerative back diseases. PMID:7317300

  13. Analysis of Protein Thermostability Enhancing Factors in Industrially Important Thermus Bacteria Species

    PubMed Central

    Kumwenda, Benjamin; Litthauer, Derek; Bishop, Özlem Tastan; Reva, Oleg

    2013-01-01

    Elucidation of evolutionary factors that enhance protein thermostability is a critical problem and was the focus of this work on Thermus species. Pairs of orthologous sequences of T. scotoductus SA-01 and T. thermophilus HB27, with the largest negative minimum folding energy (MFE) as predicted by the UNAFold algorithm, were statistically analyzed. Favored substitutions of amino acids residues and their properties were determined. Substitutions were analyzed in modeled protein structures to determine their locations and contribution to energy differences using PyMOL and FoldX programs respectively. Dominant trends in amino acid substitutions consistent with differences in thermostability between orthologous sequences were observed. T. thermophilus thermophilic proteins showed an increase in non-polar, tiny, and charged amino acids. An abundance of alanine substituted by serine and threonine, as well as arginine substituted by glutamine and lysine was observed in T. thermophilus HB27. Structural comparison showed that stabilizing mutations occurred on surfaces and loops in protein structures. PMID:24023508

  14. Molecular determinants for a cardiovascular collapse in anthrax

    PubMed Central

    Brojatsch, Jurgen; Casadevall, Arturo; Goldman, David L.

    2015-01-01

    Bacillus anthracis releases two bipartite proteins, lethal toxin and edema factor, that contribute significantly to the progression of anthrax-associated shock. As blocking the anthrax toxins prevents disease, the toxins are considered the main virulence factors of the bacterium. The anthrax bacterium and the anthrax toxins trigger multiorgan failure associated with enhanced vascular permeability, hemorrhage and cardiac dysfunction in animal challenge models. A recent study using mice that either lacked the anthrax toxin receptor in specific cells and corresponding mice expressing the receptor in specific cell types demonstrated that cardiovascular cells are critical for disease mediated by anthrax lethal toxin. These studies are consistent with involvement of the cardiovascular system, and with an increase of cardiac failure markers observed in human anthrax and in animal models using B. anthracis and anthrax toxins. This review discusses the current state of knowledge regarding the pathophysiology of anthrax and tries to provide a mechanistic model and molecular determinants for the circulatory shock in anthrax. PMID:24389148

  15. Eliciting the experiences of the adolescent-parent dyad following critical care admission: a pilot study.

    PubMed

    Wood, Dora; Geoghegan, Sophie; Ramnarayan, Padmanabhan; Davis, Peter J; Pappachan, John V; Goodwin, Sarah; Wray, Jo

    2018-05-01

    Critically ill adolescents are usually treated on intensive care units optimised for much older adults or younger children. The way they access and experience health services may be very different to most adolescent service users, and existing quality criteria may not apply to them. The objectives of this pilot study were, firstly, to determine whether adolescents and their families were able to articulate their experiences of their critical care admission and secondly, to identify the factors that are important to them during their intensive care unit (ICU) or high dependency unit (HDU) stay. Participants were 14-17 year olds who had previously had an emergency admission to an adult or paediatric ICU/HDU in one of four UK hospitals (two adult, two paediatric) and their parents. Semi-structured interviews were conducted with eight mother-adolescent dyads and one mother. Interviews were transcribed and analysed using framework analysis. The main reported determinant of high-quality care was the quality of interaction with staff. The significance of these interactions and their environment depended on adolescents' awareness of their surroundings, which was often limited in ICU and changed significantly over the course of their illness. Qualitative interview methodology would be difficult to scale up for this group. What is known • Critically ill adolescents are usually treated on intensive care units optimised for older adults or younger children. • The way they access and experience health services may be different to most adolescent patients; existing quality criteria may not apply. What is new • Reported determinants of high-quality care were age-appropriateness of the environment, respectfulness and friendliness of staff, communication and inclusion in healthcare decisions. • The significance of these depended on adolescents' awareness of their surroundings, which was often limited and changed over the course of their illness.

  16. Group cohesion and organizational commitment: protective factors for nurse residents' job satisfaction, compassion fatigue, compassion satisfaction, and burnout.

    PubMed

    Li, Angela; Early, Sean F; Mahrer, Nicole E; Klaristenfeld, Jessica L; Gold, Jeffrey I

    2014-01-01

    Stress can have detrimental effects on nurse residents' levels of job satisfaction, compassion, fatigue, and burnout. This can lead to high turnover rates and poor quality of care among novice nurses. Therefore, it is critical to identify protective factors to prevent the onset of negative nurse outcomes (compassion fatigue, burnout, and job dissatisfaction) and to promote positive nurse outcomes (job satisfaction, compassion satisfaction). This study aimed to determine whether factors such as group cohesion and organizational commitment would be protective and moderate the association between stress exposure and posttraumatic stress symptoms and other negative nurse outcomes, thus facilitating positive outcomes. Findings showed that group cohesion was effective in moderating the negative effects of current stress exposure and posttraumatic stress symptoms on negative nurse outcomes, specifically on increased compassion fatigue and burnout, and reduced compassion satisfaction. In addition, organizational commitment was determined to promote positive nurse outcomes such as job satisfaction and compassion satisfaction. The study findings are promising, as retention of quality nurses is a significant problem for hospitals. Nurse managers and hospital administrators should be aware of the benefits of group cohesion and organizational commitment and strive to make the promotion of these factors a priority. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. How Stuttering Develops: The Multifactorial Dynamic Pathways Theory

    PubMed Central

    Weber, Christine

    2017-01-01

    Purpose We advanced a multifactorial, dynamic account of the complex, nonlinear interactions of motor, linguistic, and emotional factors contributing to the development of stuttering. Our purpose here is to update our account as the multifactorial dynamic pathways theory. Method We review evidence related to how stuttering develops, including genetic/epigenetic factors; motor, linguistic, and emotional features; and advances in neuroimaging studies. We update evidence for our earlier claim: Although stuttering ultimately reflects impairment in speech sensorimotor processes, its course over the life span is strongly conditioned by linguistic and emotional factors. Results Our current account places primary emphasis on the dynamic developmental context in which stuttering emerges and follows its course during the preschool years. Rapid changes in many neurobehavioral systems are ongoing, and critical interactions among these systems likely play a major role in determining persistence of or recovery from stuttering. Conclusion Stuttering, or childhood onset fluency disorder (Diagnostic and Statistical Manual of Mental Disorders, 5th edition; American Psychiatric Association [APA], 2013), is a neurodevelopmental disorder that begins when neural networks supporting speech, language, and emotional functions are rapidly developing. The multifactorial dynamic pathways theory motivates experimental and clinical work to determine the specific factors that contribute to each child's pathway to the diagnosis of stuttering and those most likely to promote recovery. PMID:28837728

  18. Critical reappraisal of risk factors for occurrence of hepatocellular carcinoma in patients with hepatitis C virus

    PubMed Central

    Bruno, Savino; Savojardo, Daniela; Almasio, Piero L; Mondelli, Mario U

    2011-01-01

    More than one and half of current cases of hepatocellular carcinoma in the US, Europe, and Japan are attributable to hepatitis C virus (HCV) infection. HCV is also the primary cause of death in patients with HCV-related cirrhosis, with annual incidences of 0.5%–5% in Europe and 4%–10% in Asia. Screening is based on serum alpha-fetoprotein determination and liver ultrasound scan, but the sensitivity of the former is far less than optimal, and screening intervals are still poorly defined for the latter. Risk factors related to the host or environment, or both, appear to be more relevant than viral factors, such as HCV genotype, in determining disease progression to cirrhosis and cancer, and include age, male gender, severity of liver disease at presentation, coinfection with hepatitis B virus or human immunodeficiency virus, and alcohol abuse. Early liver transplantation in selected cases can be curative, but most patients are not eligible for liver grafting and are treated with locoregional ablative therapies, after which recurrence is common. Recently, orally available inhibitors of the vascular endothelial growth factor receptor have shown a significant, albeit modest, increment of survival in patients with advanced hepatocellular carcinoma, thus paving the way for modern molecular approaches to treatment of this highly malignant tumor. PMID:24367218

  19. How Stuttering Develops: The Multifactorial Dynamic Pathways Theory.

    PubMed

    Smith, Anne; Weber, Christine

    2017-09-18

    We advanced a multifactorial, dynamic account of the complex, nonlinear interactions of motor, linguistic, and emotional factors contributing to the development of stuttering. Our purpose here is to update our account as the multifactorial dynamic pathways theory. We review evidence related to how stuttering develops, including genetic/epigenetic factors; motor, linguistic, and emotional features; and advances in neuroimaging studies. We update evidence for our earlier claim: Although stuttering ultimately reflects impairment in speech sensorimotor processes, its course over the life span is strongly conditioned by linguistic and emotional factors. Our current account places primary emphasis on the dynamic developmental context in which stuttering emerges and follows its course during the preschool years. Rapid changes in many neurobehavioral systems are ongoing, and critical interactions among these systems likely play a major role in determining persistence of or recovery from stuttering. Stuttering, or childhood onset fluency disorder (Diagnostic and Statistical Manual of Mental Disorders, 5th edition; American Psychiatric Association [APA], 2013), is a neurodevelopmental disorder that begins when neural networks supporting speech, language, and emotional functions are rapidly developing. The multifactorial dynamic pathways theory motivates experimental and clinical work to determine the specific factors that contribute to each child's pathway to the diagnosis of stuttering and those most likely to promote recovery.

  20. Determinants of cocaine self-administration by laboratory animals.

    PubMed

    Woolverton, W L

    1992-01-01

    The reinforcing effect of a drug is that effect that increases the probability that the drug will be self-administered again. Like other drug effects, a reinforcing effect is the result of an interaction between organism, drug and environment. Laboratory research using animal subjects has helped elucidate the contribution of each of these factors to the self-administration of cocaine. A substantial amount of research indicates that increased dopamine neurotransmission in the brain, particularly in mesolimbic and mesocortical regions, plays a major role in cocaine self-administration. Both indirect and direct dopamine agonists can function as positive reinforcers in animals, whereas noradrenergic and serotonergic (5-HT, 5-hydroxytryptamine) agonists have not been found to do so. In addition, evidence suggests that dopamine but not noradrenaline (norepinephrine) or serotonin antagonists can attenuate the reinforcing effect of cocaine. Environmental factors have also been shown to be critical determinants of the reinforcing effect of cocaine. The schedule of reinforcement essentially determines the rate and pattern of drug-maintained behaviour. In addition, punishing self-administration, increasing the value of alternative reinforcers that are available, and increasing the cost of cocaine have all been shown to decrease the reinforcing effect of cocaine. With regard to organismic factors, recent research has suggested that there are significant genetic determinants of cocaine consumption. Taken together these research findings in animals imply that certain individuals may be more sensitive to the reinforcing effect of cocaine but that cocaine abuse can be decreased by pharmacological or behavioural means or by a combination of the two.

  1. Critical consideration of the multiplicity of experimental and organismic determinants of pyrethroid neurotoxicity: a proof of concept.

    PubMed

    Wolansky, M J; Tornero-Velez, R

    2013-01-01

    Pyrethroids (PYR) are pesticides with high insecticidal activity that may disrupt neuronal excitability in target and nontarget species. The accumulated evidence consistently showed that this neurophysiologic action is followed by alterations in motor, sensorimotor, neuromuscular, and thermoregulatory responses. Nevertheless, there are some equivocal results regarding the potency of PYR in lab animals. The estimation of potency is an important step in pesticide chemical risk assessment. In order to identify the variables influencing neurobehavioral findings across PYR studies, evidence on experimental and organismic determinants of acute PYR-induced neurotoxicity was reviewed in rodents. A comprehensive analysis of these studies was conducted focusing on test material and dosing conditions, testing conditions, animal models, and other determinants such as testing room temperature. Variations in the severity of the neurotoxicity, under lab-controlled conditions, was explained based upon factors including influence of animal species and age, test material features such as chemical structure and stereochemistry, and dosing conditions such as vehicle, route of exposure, and dose volume. If not controlled, the interplay of these factors may lead to large variance in potency estimation. This review examined the scope of acute toxicological data required to determine the safety of pesticide products, and factors and covariates that need to be controlled in order to ensure that predictivity and precaution are balanced in a risk assessment process within a reasonable time-frame, using acute PYR-induced neurotoxicity in rodents as an exemplar.

  2. Critical factors for the return-to-work process among people with affective disorders: Voices from two vocational approaches.

    PubMed

    Porter, Susann; Lexén, Annika; Johansson, Suzanne; Bejerholm, Ulrika

    2018-05-22

    Depression is among the major causes of disability with a negative impact on both daily life and work performance. Whilst depression is the primary cause of sick-leave and unemployment in today's workplace there is a lack of knowledge of the needs of individuals with depression regarding their return-to-work (RTW) process. To explore which factors are of critical importance for people suffering from depression and who also are unemployed in their RTW-process and to explore the impact of two vocational approaches on the service users' experiences. The study included participants in two vocational rehabilitation approaches; Individual Enabling and Support (IES) and Traditional Vocational Rehabilitation (TVR). Qualitative methods were applied to explore critical factors in the RTW-process. Individuals with affective disorders including depression and bipolar disorder were included.RESULTSThree themes emerged as critical factors; Experiencing hope and power, Professionals' positive attitudes, beliefs and behaviours, and Employing a holistic perspective and integrating health and vocational service.CONCLUSIONThis study has demonstrated critical factors for the return-to-work process as experienced by persons with depression. To experience hope and power, to meet professionals that believe "you can work", who use a person-centred and holistic service approach, are such factors necessary for gaining a real job. In particular, professionals in TVR need to embrace this understanding since their services were not experienced as including these elements.

  3. What makes champions? A review of the relative contribution of genes and training to sporting success.

    PubMed

    Tucker, Ross; Collins, Malcolm

    2012-06-01

    Elite sporting performance results from the combination of innumerable factors, which interact with one another in a poorly understood but complex manner to mould a talented athlete into a champion. Within the field of sports science, elite performance is understood to be the result of both training and genetic factors. However, the extent to which champions are born or made is a question that remains one of considerable interest, since it has implications for talent identification and management, as well as for how sporting federations allocate scarce resources towards the optimisation of high-performance programmes. The present review describes the contributions made by deliberate practice and genetic factors to the attainment of a high level of sporting performance. The authors conclude that although deliberate training and other environmental factors are critical for elite performance, they cannot by themselves produce an elite athlete. Rather, individual performance thresholds are determined by our genetic make-up, and training can be defined as the process by which genetic potential is realised. Although the specific details are currently unknown, the current scientific literature clearly indicates that both nurture and nature are involved in determining elite athletic performance. In conclusion, elite sporting performance is the result of the interaction between genetic and training factors, with the result that both talent identification and management systems to facilitate optimal training are crucial to sporting success.

  4. Analysis of Variations in Hospital Use by Medicare Patients in Psro Areas, 1974-1977

    PubMed Central

    Deacon, Ronald; Lubitz, James; Gornick, Marian; Newton, Marilyn

    1979-01-01

    A study of the use of short-stay hospitals in PSRO areas by Medicare enrollees aged 65 and over for the period 1974 through 1977 revealed that discharge rates increased, average length of stay (ALOS) decreased, and days-of-care rates remained relatively constant in nearly all of the PSRO areas. The data show large variations in hospital use in PSRO areas within States and HEW regions, and suggest that factors within the area are critical determinants of hospital utilization. This study presents important implications for PSRO program policy for it suggests that factors other than physician and hospital behavior should also be considered when setting objectives for reducing misutilization and improving the quality of health care. PMID:10309054

  5. Ionization-potential depression and dynamical structure factor in dense plasmas

    NASA Astrophysics Data System (ADS)

    Lin, Chengliang; Röpke, Gerd; Kraeft, Wolf-Dietrich; Reinholz, Heidi

    2017-07-01

    The properties of a bound electron system immersed in a plasma environment are strongly modified by the surrounding plasma. The modification of an essential quantity, the ionization energy, is described by the electronic and ionic self-energies, including dynamical screening within the framework of the quantum statistical theory. Introducing the ionic dynamical structure factor as the indicator for the ionic microfield, we demonstrate that ionic correlations and fluctuations play a critical role in determining the ionization potential depression. This is, in particular, true for mixtures of different ions with large mass and charge asymmetry. The ionization potential depression is calculated for dense aluminum plasmas as well as for a CH plasma and compared to the experimental data and more phenomenological approaches used so far.

  6. Inconsistent Regolith Thermal Control of Hydrogen Distributions at the Moons South Pole

    NASA Technical Reports Server (NTRS)

    McClanahan, T. P.; Mitrofanov, I.; Boynton, W. V.; Chin, G.; Litvak, M.; Livengood, Tim; Sanin, A.; Starr, R. D.; Su, Jian; Hamara, D.; hide

    2017-01-01

    Introduction: For over fifty years, intense interest has focused on determining if, where, and how much hydrogen (H) may be found near the Moons poles [1]. Driving the ongoing interest has been the critical role that H volatiles must play as a resource for human missions [2]. Now, with several lines of evidence consistently indicating that H concentrations are enhanced in some permanently shadowed regions (PSRs), plus the possibility of diurnally-dependent volatile H concentrations [3-8], investigations are shifting towards understanding the sources of H and factors that govern concentrations. For the last seven-plus years, the Lunar Reconnaissance Orbiter (LRO) has collected an unparalleled temporal and spatial record of geophysical factors that may govern the Moons H distribution [9]. XXXX

  7. Transcriptional integration of mitogenic and mechanical signals by Myc and YAP.

    PubMed

    Croci, Ottavio; De Fazio, Serena; Biagioni, Francesca; Donato, Elisa; Caganova, Marieta; Curti, Laura; Doni, Mirko; Sberna, Silvia; Aldeghi, Deborah; Biancotto, Chiara; Verrecchia, Alessandro; Olivero, Daniela; Amati, Bruno; Campaner, Stefano

    2017-10-15

    Mammalian cells must integrate environmental cues to determine coherent physiological responses. The transcription factors Myc and YAP-TEAD act downstream from mitogenic signals, with the latter responding also to mechanical cues. Here, we show that these factors coordinately regulate genes required for cell proliferation. Activation of Myc led to extensive association with its genomic targets, most of which were prebound by TEAD. At these loci, recruitment of YAP was Myc-dependent and led to full transcriptional activation. This cooperation was critical for cell cycle entry, organ growth, and tumorigenesis. Thus, Myc and YAP-TEAD integrate mitogenic and mechanical cues at the transcriptional level to provide multifactorial control of cell proliferation. © 2017 Croci et al.; Published by Cold Spring Harbor Laboratory Press.

  8. Using Fuzzy Multiple Criteria Decision-Making Approach for Assessing the Risk of Railway Reconstruction Project in Taiwan

    PubMed Central

    Yu, Shih-Heng; Chang, Dong-Shang

    2014-01-01

    This study investigates the risk factors in railway reconstruction project through complete literature reviews on construction project risks and scrutinizing experiences and challenges of railway reconstructions in Taiwan. Based on the identified risk factors, an assessing framework based on the fuzzy multicriteria decision-making (fuzzy MCDM) approach to help construction agencies build awareness of the critical risk factors on the execution of railway reconstruction project, measure the impact and occurrence likelihood for these risk factors. Subjectivity, uncertainty and vagueness within the assessment process are dealt with using linguistic variables parameterized by trapezoid fuzzy numbers. By multiplying the degree of impact and the occurrence likelihood of risk factors, estimated severity values of each identified risk factor are determined. Based on the assessment results, the construction agencies were informed of what risks should be noticed and what they should do to avoid the risks. That is, it enables construction agencies of railway reconstruction to plan the appropriate risk responses/strategies to increase the opportunity of project success and effectiveness. PMID:24772014

  9. Turbidity of a binary fluid mixture: Determining eta

    NASA Technical Reports Server (NTRS)

    Jacobs, Donald T.

    1994-01-01

    A ground based (1-g) experiment is in progress that will measure the turbidity of a density-matched, binary fluid mixture extremely close to the critical point. By covering the range of reduced temperatures t is equivalent to (T-T(sub c))/T(sub c) from 10(exp -8) to 10(exp -2), the turbidity measurements will allow the critical exponent eta to be determined. No experiment has determined a value of the critical exponent eta, yet its value is significant to theorists in critical phenomena. Interpreting the turbidity correctly is important if future NASA flight experiments use turbidity as an indirect measurement of relative temperature in shuttle experiments on critical phenomena in fluids.

  10. Website Service Quality in Ireland: An Empirical Study

    NASA Astrophysics Data System (ADS)

    Connolly, Regina

    Despite the fact that service quality is a critical determinant of website success, studies show that consumers frequently view the service quality delivered through websites as unsatisfactory. This paper outlines a study that investigated the dimensions of website service excellence valued by Irish customers of a small-to-medium enterprise specialising in gifts. The E-S-QUAL measurement instrument was applied to the customers who purchase products online from this retailer, in order to determine their purchasing patterns and the dimensions of e-service quality that they value. The results of this study indicate the effectiveness of the instrument in determining gaps in e-service quality. The findings will be of benefit both to practitioners and researchers seeking to improve their understanding of the factors that contribute towards the creation and maintenance of consumer satisfaction in Irish online transactions.

  11. Prolonged Prothrombin Time After Recombinant Activated Factor VII Therapy in Critically Bleeding Trauma Patients Is Associated With Adverse Outcomes

    DTIC Science & Technology

    2010-07-01

    using the FVII coagulant activity (FVII:C) assay, a one- stage assay using thromboplastin tissue factor , which quantifies FVII clotting activity in...and the resultant production of dysfunctional factors II, VII, and X. This study focused on PT specifically because this measure examines the TF...ORIGINAL ARTICLE Prolonged Prothrombin Time After Recombinant Activated Factor VII Therapy in Critically Bleeding Trauma Patients Is Associated With

  12. Self-assessment, reflection on practice and critical thinking in nursing students.

    PubMed

    Siles-González, José; Solano-Ruiz, Carmen

    2016-10-01

    In accordance with the principles of the European Higher Education Area, the aim of this study was to contribute to the implementation of self-assessment through the application of reflection on learning and critical thinking. The theoretical framework employed was Habermas's critical theory and emancipatory interest as a preliminary step to generate educational transformations. The methodological contribution is the design a student self-assessment document that promotes reflection on action and critical thinking. The development of assessment through peer evaluation and other intermediate solutions until achieving self-assessment entails a shift in the educational and scientific paradigm, but also involves the implementation in practice of democratic and ethical principles, values and premises in society. Self-assessment is a novel concept for students, and obliges them to reinterpret their role. Due to the diversity of students' principles, values, motivations, interests and aspirations, this reinterpretation of their role can have a positive outcome, stimulating an active and critical attitude towards group work and self-assessment; or, on the contrary, can generate a stance characterised by disinterest, passivity and lack of critical thinking. The forms of assessment adopted in a given educational system reflect ways of thinking related to ideologies, values, ethical principles and educational paradigms: in order to render implementation of effective self-assessment feasible, it is necessary to undertake structural and regulatory reforms. Students have little experience of reflection on practice or critical thinking. Massification and cultural and structural factors determine the form of assessment. In this context, it would seem advisable to move towards self-assessment gradually and cautiously. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Water properties in seeds from wild species native to Spain

    USDA-ARS?s Scientific Manuscript database

    Temperature, water content and relative humidity are critical factors contributing to seed longevity during storage. Water sorption isotherms describe the interrelationships between these critical factors. Understanding these relationships can lead to predictions about how best to process seeds for...

  14. Investigation of factors influencing microscopic interactions between the diamond indenter and material surfaces in nano-indentation

    NASA Astrophysics Data System (ADS)

    Wei, Qilong; Li, Xiaoyuan; Yang, Qiang; Gao, Wei

    2015-11-01

    Nano-indentation method was brought forward to replace atomic force microscopy (AFM) in simulating microscopic interactions between abrasive particles and material surfaces during polishing process. And main influencing factors including measuring parameters and material's properties were investigated thoroughly. It was found that contact force between the diamond indenter and a fused silica was about 200 μN, while it was about 470 μN between the indenter and an austenitic steel, and in both cases it did not vary with the maximal indentation force (Fmax) and the corresponding loading rate. While adhesion force between the indenter and surfaces of the two materials did not change with Fmax when the latter was less than its critical value, while it decreased monotonously with increased Fmax when the latter was higher than its critical value, with slope -1.8615 for the fused silica and -1.5403 for the austenitic steel, and the critical Fmax was about 20 mN for the fused silica and about 50 mN for the austenitic steel. According to analysis on elastic and plastic deformation during loading process and elastic recovery during unloading process, it was deduced that there would produce marked elastic recovery force when the unloading rate determined by Fmax was higher, which counteracted the measured adhesion force to some extent and made it less than its corresponding intrinsic value. And material's elasticity had an additional impact. Then it is better to adopt maximal indentation forces less than critical values of materials, to obtain accurate adhesion forces between the indenter and material surfaces, and to simulate accurately microscopic interactions during polishing process.

  15. Relationship between hyperglycemia, hormone disturbances, and clinical evolution in severely hyperglycemic post surgery critically ill children: an observational study

    PubMed Central

    2014-01-01

    Background To study hormonal changes associated with severe hyperglycemia in critically ill children and the relationship with prognosis and length of stay in intensive care. Methods Observational study in twenty-nine critically ill children with severe hyperglycemia defined as 2 blood glucose measurements greater than 180 mg/dL. Severity of illness was assessed using pediatric index of mortality (PIM2), pediatric risk of mortality (PRISM) score, and pediatric logistic organ dysfunction (PELOD) scales. Blood glucose, glycosuria, insulin, C-peptide, cortisol, corticotropin, insulinlike growth factor-1, growth hormone, thyrotropin, thyroxine, and treatment with insulin were recorded. β-cell function and insulin sensitivity and resistance were determined on the basis of the homeostatic model assessment (HOMA), using blood glucose and C-peptide levels. Results The initial blood glucose level was 249 mg/dL and fell gradually to 125 mg/dL at 72 hours. Initial β-cell function (49.2%) and insulin sensitivity (13.2%) were low. At the time of diagnosis of hyperglycemia, 50% of the patients presented insulin resistance and β-cell dysfunction, 46% presented isolated insulin resistance, and 4% isolated β-cell dysfunction. β-cell function improved rapidly but insulin resistance persisted. Initial glycemia did not correlate with any other factor, and there was no relationship between glycemia and mortality. Patients who died had higher cortisol and growth hormone levels at diagnosis. Length of stay was correlated by univariate analysis, but not by multivariate analysis, with C-peptide and glycemic control at 24 hours, insulin resistance, and severity of illness scores. Conclusions Critically ill children with severe hyperglycemia initially present decreased β-cell function and insulin sensitivity. Nonsurvivors had higher cortisol and growth hormone levels and developed hyperglycemia later than survivors. PMID:24628829

  16. Predictors of Mortality in the Critically Ill Cirrhotic Patient: Is the Model for End-Stage Liver Disease Enough?

    PubMed

    Annamalai, Alagappan; Harada, Megan Y; Chen, Melissa; Tran, Tram; Ko, Ara; Ley, Eric J; Nuno, Miriam; Klein, Andrew; Nissen, Nicholas; Noureddin, Mazen

    2017-03-01

    Critically ill cirrhotics require liver transplantation urgently, but are at high risk for perioperative mortality. The Model for End-stage Liver Disease (MELD) score, recently updated to incorporate serum sodium, estimates survival probability in patients with cirrhosis, but needs additional evaluation in the critically ill. The purpose of this study was to evaluate the predictive power of ICU admission MELD scores and identify clinical risk factors associated with increased mortality. This was a retrospective review of cirrhotic patients admitted to the ICU between January 2011 and December 2014. Patients who were discharged or underwent transplantation (survivors) were compared with those who died (nonsurvivors). Demographic characteristics, admission MELD scores, and clinical risk factors were recorded. Multivariate regression was used to identify independent predictors of mortality, and measures of model performance were assessed to determine predictive accuracy. Of 276 patients who met inclusion criteria, 153 were considered survivors and 123 were nonsurvivors. Survivor and nonsurvivor cohorts had similar demographic characteristics. Nonsurvivors had increased MELD, gastrointestinal bleeding, infection, mechanical ventilation, encephalopathy, vasopressors, dialysis, renal replacement therapy, requirement of blood products, and ICU length of stay. The MELD demonstrated low predictive power (c-statistic 0.73). Multivariate analysis identified MELD score (adjusted odds ratio [AOR] = 1.05), mechanical ventilation (AOR = 4.55), vasopressors (AOR = 3.87), and continuous renal replacement therapy (AOR = 2.43) as independent predictors of mortality, with stronger predictive accuracy (c-statistic 0.87). The MELD demonstrated relatively poor predictive accuracy in critically ill patients with cirrhosis and might not be the best indicator for prognosis in the ICU population. Prognostic accuracy is significantly improved when variables indicating organ support (mechanical ventilation, vasopressors, and continuous renal replacement therapy) are included in the model. Copyright © 2016. Published by Elsevier Inc.

  17. Critical Success Factors for E-Learning in Developing Countries: A Comparative Analysis between ICT Experts and Faculty

    ERIC Educational Resources Information Center

    Bhuasiri, Wannasiri; Xaymoungkhoun, Oudone; Zo, Hangjung; Rho, Jae Jeung; Ciganek, Andrew P.

    2012-01-01

    This study identifies the critical success factors that influence the acceptance of e-learning systems in developing countries. E-learning is a popular mode of delivering educational materials in higher education by universities throughout the world. This study identifies multiple factors that influence the success of e-learning systems from the…

  18. "In the Middle of Difficulty Lies Opportunity"--Using a Case Study to Identify Critical Success Factors Contributing to the Initiation of International Collaborative Projects

    ERIC Educational Resources Information Center

    Johnson, Ian M.

    2005-01-01

    This paper identifies factors that contribute to the successful initiation of international collaborative projects intended to support the development of education for librarianship and information sciences. It discusses the widespread failure to analyse the Critical Success Factors in international collaborative projects and proposes a case study…

  19. Final Report for Regulation of Embryonic Development in Higher Plants

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

    Harada, John J.

    2013-10-22

    The overall goal of the project was to define the cellular processes that underlie embryo development in plants at a mechanistic level. Our studies focused on a critical transcriptional regulator, Arabidopsis LEAFY COTYLEDON (LEC1), that is necessary and sufficient to induce processes required for embryo development. Because LEC1 regulates lipid accumulation during the maturation phase of embryo development, information about LEC1 may be useful in designing approaches to enhance biofuel production in plants. During the tenure of this project, we determined the molecular mechanisms by which LEC1 acts as a transcription factor in embryos. We also identified genes directly regulatedmore » by LEC1 and showed that many of these genes are involved in maturation processes. This information has been useful in dissecting the gene regulatory networks controlling embryo development. Finally, LEC1 is a novel isoform of a transcription factor that is conserved among eukaryotes, and LEC1 is active primarily in seeds. Therefore, we determined that the LEC1-type transcription factors first appeared in lycophytes during land plant evolution. Together, this study provides basic information that has implications for biofuel production.« less

  20. Expressed Emotion-Criticism and Risk of Depression Onset in Children

    PubMed Central

    Burkhouse, Katie L.; Uhrlass, Dorothy J.; Stone, Lindsey B.; Knopik, Valerie S.; Gibb, Brandon E.

    2012-01-01

    Objective The primary goal of the current study was to examine the impact of maternal criticism (expressed emotion-criticism; EE-Crit) on the prospective development of depressive episodes in children. In addition to examining baseline levels of EE-Crit, we also sought to determine whether distinct subgroups (latent classes) of mothers could be identified based on the levels of EE-Crit they exhibited over a multi-wave assessment and whether that latent class membership would predict depression onset in children. Finally, we examined whether EE-Crit and maternal depression would independently predict children's depression risk or whether EE-Crit would moderate the link between maternal depression and children's depression onset. Method Children of mothers with or without a history of major depression (N=100) were assessed five times over 20 months. Children completed the Children's Depression Inventory (CDI) and mothers completed the Five Minute Speech Sample and the Beck Depression Inventory (BDI) at the baseline assessment, and at 2, 4, and 6 month follow-up assessments. Children and mothers completed diagnostic interviews assessing children's onsets of depressive episodes at the 20 month follow-up. Results Latent class analysis of the 4 waves of EE-Crit assessments revealed two distinct groups, exhibiting relatively lower versus higher levels of EE-Crit across the first 6 months of follow-up. EE-Crit latent class membership predicted children's depression onset over the subsequent 14 months. This finding was maintained after controlling for mother's and children's depressive symptoms during the initial 6 months of follow-up. Finally, maternal depression did not moderate the link between EE-Crit and childhood depression onset. Conclusions Continued exposure to maternal criticism appears to be an important risk factor for depression in children, risk that is at least partially independent of the risk conveyed by maternal depression. These results highlight the importance of a modifiable risk factor for depression–repeated exposure to maternal criticism. PMID:22838507

  1. Alarm setting for the critically ill patient: a descriptive pilot survey of nurses' perceptions of current practice in an Australian Regional Critical Care Unit.

    PubMed

    Christensen, Martin; Dodds, Andrew; Sauer, Josh; Watts, Nigel

    2014-08-01

    The aim of this survey was to assess registered nurse's perceptions of alarm setting and management in an Australian Regional Critical Care Unit. The setting and management of alarms within the critical care environment is one of the key responsibilities of the nurse in this area. However, with up to 99% of alarms potentially being false-positives it is easy for the nurse to become desensitised or fatigued by incessant alarms; in some cases up to 400 per patient per day. Inadvertently ignoring, silencing or disabling alarms can have deleterious implications for the patient and nurse. A total population sample of 48 nursing staff from a 13 bedded ICU/HDU/CCU within regional Australia were asked to participate. A 10 item open-ended and multiple choice questionnaire was distributed to determine their perceptions and attitudes of alarm setting and management within this clinical area. Two key themes were identified from the open-ended questions: attitudes towards inappropriate alarm settings and annoyance at delayed responses to alarms. A significant number of respondents (93%) agreed that alarm fatigue can result in alarm desensitisation and the disabling of alarms, whilst 81% suggested the key factors are those associated with false-positive alarms and inappropriately set alarms. This study contributes to what is known about alarm fatigue, setting and management within a critical care environment. In addition it gives an insight as to what nurses' within a regional context consider the key factors which contribute to alarm fatigue. Clearly nursing burnout and potential patient harm are important considerations for practice especially when confronted with alarm fatigue and desensitisation. Therefore, promoting and maintaining an environment of ongoing intra-professional communication and alarm surveillance are crucial in alleviating these potential problems. Copyright © 2014. Published by Elsevier Ltd.

  2. Employment Outcomes After Critical Illness: An Analysis of the Bringing to Light the Risk Factors and Incidence of Neuropsychological Dysfunction in ICU Survivors Cohort.

    PubMed

    Norman, Brett C; Jackson, James C; Graves, John A; Girard, Timothy D; Pandharipande, Pratik P; Brummel, Nathan E; Wang, Li; Thompson, Jennifer L; Chandrasekhar, Rameela; Ely, E Wesley

    2016-11-01

    To characterize survivors' employment status after critical illness and to determine if duration of delirium during hospitalization and residual cognitive function are each independently associated with decreased employment. Prospective cohort investigation with baseline and in-hospital clinical data and follow-up at 3 and 12 months. Medical and surgical ICUs at two tertiary-care hospitals. Previously employed patients from the Bringing to Light the Risk Factors and Incidence of Neuropsychological Dysfunction in ICU Survivors study who survived a critical illness due to respiratory failure or shock were evaluated for global cognition and employment status at 3- and 12-month follow-up. We used multivariable logistic regression to evaluate independent associations between employment at both 3 and 12 months and global cognitive function at the same time point, and delirium during the hospital stay. At 3-month follow-up, 113 of the total survival cohort of 448 (25%) were identified as being employed at study enrollment. Of these, 94 survived to 12-month follow-up. At 3- and 12-month follow-up, 62% and 49% had a decrease in employment, 57% and 49% of whom, respectively, were newly unemployed. After adjustment for physical health status, depressive symptoms, marital status, level of education, and severity of illness, we did not find significant predictors of employment status at 3 months, but better cognition at 12 months was marginally associated with lower odds of employment reduction at 12 months (odds ratio, 0.49; p = 0.07). Reduction in employment after critical illness was present in the majority of our ICU survivors, approximately half of which was new unemployment. Cognitive function at 12 months was a predictor of subsequent employment status. Further research is needed into the potential relationship between the impact of critical illness on cognitive function and employment status.

  3. Expressed emotion-criticism and risk of depression onset in children.

    PubMed

    Burkhouse, Katie L; Uhrlass, Dorothy J; Stone, Lindsey B; Knopik, Valerie S; Gibb, Brandon E

    2012-01-01

    The primary goal of the current study was to examine the impact of maternal criticism (expressed emotion-criticism; EE-Crit) on the prospective development of depressive episodes in children. In addition to examining baseline levels of EE-Crit, we also sought to determine whether distinct subgroups (latent classes) of mothers could be identified based on the levels of EE-Crit they exhibited over a multiwave assessment and whether that latent class membership would predict depression onset in children. Finally, we examined whether EE-Crit and maternal depression would independently predict children's depression risk or whether EE-Crit would moderate the link between maternal depression and children's depression onset. Children of mothers with or without a history of major depression (N = 100) were assessed 5 times over 20 months. Children completed the Children's Depression Inventory and mothers completed the Five Minute Speech Sample and the Beck Depression Inventory at the baseline assessment, and at 2-, 4-, and 6-month follow-up assessments. Children and mothers completed diagnostic interviews assessing children's onsets of depressive episodes at the 20-month follow-up. Latent class analysis of the 4 waves of EE-Crit assessments revealed two distinct groups, exhibiting relatively lower versus higher levels of EE-Crit across the first 6 months of follow-up. EE-Crit latent class membership predicted children's depression onset over the subsequent 14 months. This finding was maintained after controlling for mother's and children's depressive symptoms during the initial 6 months of follow-up. Finally, maternal depression did not moderate the link between EE-Crit and childhood depression onset. Continued exposure to maternal criticism appears to be an important risk factor for depression in children, risk that is at least partially independent of the risk conveyed by maternal depression. These results highlight the importance of a modifiable risk factor for depression-repeated exposure to maternal criticism.

  4. Bone mineralization in childhood and adolescence.

    PubMed

    Bachrach, L K

    1993-08-01

    Prevention of osteoporosis depends on establishing adequate peak bone mass in the first two decades of life. Achievement of this goal requires an understanding of factors that promote skeletal health. Genetic factors are important determinants of adult bone mass, but nonheritable variables, including body mass, calcium nutriture, sex steroids, and activity can strongly influence whether maximal bone mineral is achieved. Acquisition of bone mineral continues throughout childhood and adolescence, reaching a lifetime maximum in early adulthood. Adolescence is a particularly critical time for bone mineral accretion as more than half of the bone calcium is normally laid down during the teen years. Chronic illness, malnutrition, or endocrine deficiencies at this age may result in profound deficits in bone mass, which may not be fully reversible. These risk factors contribute to the osteopenia associated with anorexia nervosa, exercise-induced amenorrhea, delayed puberty, Turner's syndrome, and growth hormone deficiency.

  5. AP-1 subunits: quarrel and harmony among siblings.

    PubMed

    Hess, Jochen; Angel, Peter; Schorpp-Kistner, Marina

    2004-12-01

    The AP-1 transcription factor is mainly composed of Jun, Fos and ATF protein dimers. It mediates gene regulation in response to a plethora of physiological and pathological stimuli, including cytokines, growth factors, stress signals, bacterial and viral infections, as well as oncogenic stimuli. Studies in genetically modified mice and cells have highlighted a crucial role for AP-1 in a variety of cellular events involved in normal development or neoplastic transformation causing cancer. However, emerging evidence indicates that the contribution of AP-1 to determination of cell fates critically depends on the relative abundance of AP-1 subunits, the composition of AP-1 dimers, the quality of stimulus, the cell type and the cellular environment. Therefore, AP-1-mediated regulation of processes such as proliferation, differentiation, apoptosis and transformation should be considered within the context of a complex dynamic network of signalling pathways and other nuclear factors that respond simultaneously.

  6. [Burnout Syndrome, Family and Work Related Variables on General Practitioners in Bogota. A Strategy of Work Quality].

    PubMed

    Aguirre Roldán, Adriana María; Quijano Barriga, Ana María

    2015-01-01

    The burnout syndrome is a set of work-related symptoms related to weariness and exhaustion, in response to the emotional stress at work and its consequences. The aim of the study was to measure the frequency of burnout in General Practitioners (GPs) from 3 private institutions in Bogotá, Colombia and to determine the associated factors according to the variables taken into account. It is a descriptive cross-sectional study which was used to analyse the Questionnaire for Burnout Syndrome (CESQT). The population was 106 GPs. The level of burnout was at a critical level in 6.6% of the GP population. The variables showed that having a stable partner and children are a protective factor. By contrast, work in emergency rooms is a risk factor. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  7. Novel functions for the transcription factor E2F4 in development and disease

    PubMed Central

    Sage, Julien

    2016-01-01

    ABSTRACT The E2F family of transcription factors is a key determinant of cell proliferation in response to extra- and intra-cellular signals. Within this family, E2F4 is a transcriptional repressor whose activity is critical to engage and maintain cell cycle arrest in G0/G1 in conjunction with members of the retinoblastoma (RB) family. However, recent observations challenge this paradigm and indicate that E2F4 has a multitude of functions in cells besides this cell cycle regulatory role, including in embryonic and adult stem cells, during regenerative processes, and in cancer. Some of these new functions are independent of the RB family and involve direct activation of target genes. Here we review the canonical functions of E2F4 and discuss recent evidence expanding the role of this transcription factor, with a focus on cell fate decisions in tissue homeostasis and regeneration. PMID:27753528

  8. Network formation in a multi-asset artificial stock market

    NASA Astrophysics Data System (ADS)

    Wu, Songtao; He, Jianmin; Li, Shouwei; Wang, Chao

    2018-04-01

    A multi-asset artificial stock market is developed. In the market, stocks are assigned to a number of sectors and traded by heterogeneous investors. The mechanism of continuous double auction is employed to clear order book and form daily closed prices. Simulation results of prices at the sector level show an intra-sector similarity and inter-sector distinctiveness, and returns of individual stocks have stylized facts that are ubiquitous in the real-world stock market. We find that the market risk factor has critical impact on both network topology transition and connection formation, and that sector risk factors account for the formation of intra-sector links and sector-based local interaction. In addition, the number of community in threshold-based networks is correlated negatively and positively with the value of correlation coefficients and the ratio of intra-sector links, which are respectively determined by intensity of sector risk factors and the number of sectors.

  9. Economic and Social Impact of Influenza Mitigation Strategies by Demographic Class

    PubMed Central

    Barrett, Chris; Bisset, Keith; Leidig, Jonathan; Marathe, Achla; Marathe, Madhav

    2011-01-01

    Background We aim to determine the economic and social impact of typical interventions proposed by the public health officials and preventive behavioral changes adopted by the private citizens in the event of a “flu-like” epidemic. Method We apply an individual-based simulation model to the New River Valley area of Virginia for addressing this critical problem. The economic costs include not only the loss in productivity due to sickness but also the indirect cost incurred through disease avoidance and caring for dependents. Results The results show that the most important factor responsible for preventing income loss is the modification of individual behavior; it drops the total income loss by 62% compared to the base case. The next most important factor is the closure of schools which reduces the total income loss by another 40%. Conclusions The preventive behavior of the private citizens is the most important factor in controlling the epidemic. PMID:21339828

  10. Determinants of voluntary carbon disclosure in the corporate real estate sector of Malaysia.

    PubMed

    Kalu, Joseph Ufere; Buang, Alias; Aliagha, Godwin Uche

    2016-11-01

    Corporate real estate management holds the tent that risk which is not understood cannot be measured or managed. The effect of global warming on real estate investment and need for climate change mitigation through disclosures by companies of carbon emission information has becomes a sine-qua-non for the management of companies' carbon footprint and reducing its overall effect on global warming. This study applied the structural equation modeling technique to determine the determinants influencing Carbon Disclosure in Real Estate Companies in a developing economy. The analysis was based on 2013 annual reports of 126 property sector companies listed in Malaysia stock exchange market. The model was validated through convergent validity, discriminant validity, composite reliability and goodness of fit. The result reveals that social and financial market were critical determinant factors for carbon disclosure while the economic and institutional factors did not achieve significant effect on voluntary carbon disclosure. The result is consistent with legitimacy theory and agency theories. The implication of this finding is that increase in public education and awareness will enhance community demand for disclosure from companies and they will increase level of disclosure; also as financial institutions consider sustainability practice as a viable investment and term for credit financing, companies will be motivated to increase disclosure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Recommendations to the Federal Railroad Administration concerning critical factors in railroad employee medical standards.

    DOT National Transportation Integrated Search

    1976-03-01

    This report discusses critical factors which should be considered in the preparation of medical standards for locomotive engineers or other individuals who operate moving equipment. In many instances, a guideline is not proposed because case by case ...

  12. Determinants of under-five mortality in rural and urban Kenya.

    PubMed

    Ettarh, R R; Kimani, J

    2012-01-01

    The disparity in under-five year-old mortality rates between rural and urban areas in Kenya (also reported in other in sub-Saharan African countries), is a critical national concern. The objective of this study was to investigate the influence of geographical location and maternal factors on the likelihood of mortality among under-five children in rural and urban areas in Kenya. Data from the 2008-2009 Kenya Demographic and Health Survey were used to determine mortality among under-five children (n=16,162) in rural and urban areas in the 5 years preceding the survey. Multivariate analysis was used to compare the influence of key risk factors in rural and urban areas. Overall, the likelihood of death among under-five children in the rural areas was significantly higher than that in the urban areas (p<0.05). Household poverty was a key predictor for mortality in the rural areas, but the influence of breastfeeding was similar in the two areas. The likelihood of under-five mortality was significantly higher in the rural areas of Coast, Nyanza and Western Provinces than in Central Province. The study shows that the determinants of under-five mortality differ in rural and urban areas in Kenya. Innovative and targeted strategies are required to address rural poverty and province-specific sociocultural factors in order to improve child survival in rural Kenya.

  13. A Protocol for Lifetime Energy and Environmental Impact Assessment of Building Insulation Materials

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

    Shrestha, Som S; Biswas, Kaushik; Desjarlais, Andre Omer

    This article describes a proposed protocol that is intended to provide a comprehensive list of factors to be considered in evaluating the direct and indirect environmental impacts of building insulation materials, as well as detailed descriptions of standardized calculation methodologies to determine those impacts. The energy and environmental impacts of insulation materials can generally be divided into two categories: (1) direct impact due to the embodied energy of the insulation materials and other factors, and (2) indirect or environmental impacts avoided as a result of reduced building energy use due to addition of insulation. Standards and product category rules existmore » that provide guidelines about the life cycle assessment (LCA) of materials, including building insulation products. However, critical reviews have suggested that these standards fail to provide complete guidance to LCA studies and suffer from ambiguities regarding the determination of the environmental impacts of building insulation and other products. The focus of the assessment protocol described here is to identify all factors that contribute to the total energy and environmental impacts of different insulation products and, more importantly, provide standardized determination methods that will allow comparison of different insulation material types. Further, the intent is not to replace current LCA standards but to provide a well-defined, easy-to-use comparison method for insulation materials using existing LCA guidelines.« less

  14. Minireview: Hormones and human sexual orientation.

    PubMed

    Balthazart, Jacques

    2011-08-01

    Many people believe that sexual orientation (homosexuality vs. heterosexuality) is determined by education and social constraints. There are, however, a large number of studies indicating that prenatal factors have an important influence on this critical feature of human sexuality. Sexual orientation is a sexually differentiated trait (over 90% of men are attracted to women and vice versa). In animals and men, many sexually differentiated characteristics are organized during early life by sex steroids, and one can wonder whether the same mechanism also affects human sexual orientation. Two types of evidence support this notion. First, multiple sexually differentiated behavioral, physiological, or even morphological traits are significantly different in homosexual and heterosexual populations. Because some of these traits are known to be organized by prenatal steroids, including testosterone, these differences suggest that homosexual subjects were, on average, exposed to atypical endocrine conditions during development. Second, clinical conditions associated with significant endocrine changes during embryonic life often result in an increased incidence of homosexuality. It seems therefore that the prenatal endocrine environment has a significant influence on human sexual orientation but a large fraction of the variance in this behavioral characteristic remains unexplained to date. Genetic differences affecting behavior either in a direct manner or by changing embryonic hormone secretion or action may also be involved. How these biological prenatal factors interact with postnatal social factors to determine life-long sexual orientation remains to be determined.

  15. Minireview: Hormones and Human Sexual Orientation

    PubMed Central

    2011-01-01

    Many people believe that sexual orientation (homosexuality vs. heterosexuality) is determined by education and social constraints. There are, however, a large number of studies indicating that prenatal factors have an important influence on this critical feature of human sexuality. Sexual orientation is a sexually differentiated trait (over 90% of men are attracted to women and vice versa). In animals and men, many sexually differentiated characteristics are organized during early life by sex steroids, and one can wonder whether the same mechanism also affects human sexual orientation. Two types of evidence support this notion. First, multiple sexually differentiated behavioral, physiological, or even morphological traits are significantly different in homosexual and heterosexual populations. Because some of these traits are known to be organized by prenatal steroids, including testosterone, these differences suggest that homosexual subjects were, on average, exposed to atypical endocrine conditions during development. Second, clinical conditions associated with significant endocrine changes during embryonic life often result in an increased incidence of homosexuality. It seems therefore that the prenatal endocrine environment has a significant influence on human sexual orientation but a large fraction of the variance in this behavioral characteristic remains unexplained to date. Genetic differences affecting behavior either in a direct manner or by changing embryonic hormone secretion or action may also be involved. How these biological prenatal factors interact with postnatal social factors to determine life-long sexual orientation remains to be determined. PMID:21693676

  16. Sensory factors limiting horizontal and vertical visual span for letter recognition

    PubMed Central

    Yu, Deyue; Legge, Gordon E.; Wagoner, Gunther; Chung, Susana T. L.

    2014-01-01

    Reading speed for English text is slower for text oriented vertically than horizontally. Yu, Park, Gerold, and Legge (2010) showed that slower reading of vertical text is associated with a smaller visual span (the number of letters recognized with high accuracy without moving the eyes). Three possible sensory determinants of the size of the visual span are: resolution (decreasing acuity at letter positions farther from the midline), mislocations (uncertainty about the relative position of letters in strings), and crowding (interference from flanking letters in recognizing the target letter). In the present study, we asked which of these factors is most important in determining the size of the visual span, and likely in turn in determining the horizontal/vertical difference in reading when letter size is above the critical print size for reading. We used a decomposition analysis to represent constraints due to resolution, mislocations, and crowding as losses in information transmitted (in bits) about letter recognition. Across vertical and horizontal conditions, crowding accounted for 75% of the loss in information, mislocations accounted for 19% of the loss, and declining acuity away from fixation accounted for only 6%. We conclude that crowding is the major factor limiting the size of the visual span, and that the horizontal/vertical difference in the size of the visual span is associated with stronger crowding along the vertical midline. PMID:25187253

  17. Sensory factors limiting horizontal and vertical visual span for letter recognition

    PubMed Central

    Yu, Deyue; Legge, Gordon E.; Wagoner, Gunther; Chung, Susana T. L.

    2014-01-01

    Reading speed for English text is slower for text oriented vertically than horizontally. Yu, Park, Gerold, and Legge (2010) showed that slower reading of vertical text is associated with a smaller visual span (the number of letters recognized with high accuracy without moving the eyes). Three possible sensory determinants of the size of the visual span are: resolution (decreasing acuity at letter positions farther from the midline), mislocations (uncertainty about the relative position of letters in strings), and crowding (interference from flanking letters in recognizing the target letter). In the present study, we asked which of these factors is most important in determining the size of the visual span, and likely in turn in determining the horizontal/vertical difference in reading when letter size is above the critical print size for reading. We used a decomposition analysis to represent constraints due to resolution, mislocations, and crowding as losses in information transmitted (in bits) about letter recognition. Across vertical and horizontal conditions, crowding accounted for 75% of the loss in information, mislocations accounted for 19% of the loss, and declining acuity away from fixation accounted for only 6%. We conclude that crowding is the major factor limiting the size of the visual span, and that the horizontal/vertical difference in the size of the visual span is associated with stronger crowding along the vertical midline.

  18. Team effectiveness in Non-Governmental Organizations (NGOs) projects.

    PubMed

    Latif, Khawaja Fawad; Williams, Nigel

    2017-10-01

    The incorporation of team context into research and practice regarding team effectiveness in NGOs projects is a constant challenge. The research seeks to address the gap and identify the critical determinants of team effectiveness in projects undertaken by non-governmental organizations. Using a systematic process, the study involved both literature and focus group discussions to generate the required items. A total of 157 respondents (Team Members and Team Leaders) were part of the study that filled the questionnaires. Using exploratory factor analysis followed by confirmatory factor analysis, both convergent and discriminant validity was established. The present study found that team effectiveness in NGO social projects has a total of seven dimensions namely: Inter team coordination, community social linkage, team performance, knowledge, skills, and attitudes, leadership communication and engagement, decision making and information sharing, and team formation. There is a significant lack of research on team effectiveness in NGO projects. Where considerably large proportion of research on team effectiveness has focused on the corporate sector, the non-governmental teams have been neglected. This study clearly highlights the determinants that make up team effectiveness in NGOs. The determinants identified will help to specifically look at the effectiveness of teams in NGO projects. The study would help NGOs identify the dimensions in which they may be performing in a weaker manner and direct their energies in improving the factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The DNA-encoded nucleosome organization of a eukaryotic genome.

    PubMed

    Kaplan, Noam; Moore, Irene K; Fondufe-Mittendorf, Yvonne; Gossett, Andrea J; Tillo, Desiree; Field, Yair; LeProust, Emily M; Hughes, Timothy R; Lieb, Jason D; Widom, Jonathan; Segal, Eran

    2009-03-19

    Nucleosome organization is critical for gene regulation. In living cells this organization is determined by multiple factors, including the action of chromatin remodellers, competition with site-specific DNA-binding proteins, and the DNA sequence preferences of the nucleosomes themselves. However, it has been difficult to estimate the relative importance of each of these mechanisms in vivo, because in vivo nucleosome maps reflect the combined action of all influencing factors. Here we determine the importance of nucleosome DNA sequence preferences experimentally by measuring the genome-wide occupancy of nucleosomes assembled on purified yeast genomic DNA. The resulting map, in which nucleosome occupancy is governed only by the intrinsic sequence preferences of nucleosomes, is similar to in vivo nucleosome maps generated in three different growth conditions. In vitro, nucleosome depletion is evident at many transcription factor binding sites and around gene start and end sites, indicating that nucleosome depletion at these sites in vivo is partly encoded in the genome. We confirm these results with a micrococcal nuclease-independent experiment that measures the relative affinity of nucleosomes for approximately 40,000 double-stranded 150-base-pair oligonucleotides. Using our in vitro data, we devise a computational model of nucleosome sequence preferences that is significantly correlated with in vivo nucleosome occupancy in Caenorhabditis elegans. Our results indicate that the intrinsic DNA sequence preferences of nucleosomes have a central role in determining the organization of nucleosomes in vivo.

  20. Intact and Degraded Criticality Calculations for the Codisposal of Shippingport LWBR Spent Nuclear Fuel in a Waste Package

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

    L.M. Montierth

    2000-09-15

    The objective of this calculation is to characterize the nuclear criticality safety concerns associated with the codisposal of the U.S. Department of Energy's (DOE) Shippingport Light Water Breeder Reactor (SP LWBR) Spent Nuclear Fuel (SNF) in a 5-Defense High-Level Waste (5-DHLW) Waste Package (WP), which is to be placed in a Monitored Geologic Repository (MGR). The scope of this calculation is limited to the determination of the effective neutron multiplication factor (K{sub eff}) for intact- and degraded-mode internal configurations of the codisposal WP containing Shippingport LWBR seed-type assemblies. The results of this calculation will be used to evaluate criticality issuesmore » and support the analysis that is planed to be performed to demonstrate the viability of the codisposal concept for the MGR. This calculation is associated with the waste package design and was performed in accordance with the DOE SNF Analysis Plan for FY 2000 (See Ref. 22). The document has been prepared in accordance with the Administrative Procedure AP-3.12Q, Calculations (Ref. 23).« less

Top