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Sample records for variables contributed significantly

  1. Statistical Significance of the Contribution of Variables to the PCA Solution: An Alternative Permutation Strategy

    Science.gov (United States)

    Linting, Marielle; van Os, Bart Jan; Meulman, Jacqueline J.

    2011-01-01

    In this paper, the statistical significance of the contribution of variables to the principal components in principal components analysis (PCA) is assessed nonparametrically by the use of permutation tests. We compare a new strategy to a strategy used in previous research consisting of permuting the columns (variables) of a data matrix…

  2. Significant variables associated with epilepsy

    International Nuclear Information System (INIS)

    Cheema, F.A.; Qayyum, K.; Ahmad, N.; Makhdoomi, A.; Safdar, A.; Asif, A.; Chaudhry, H.R.

    2003-01-01

    Objective: To study the characteristics of the epileptics and the risk factors contributing to the development of epilepsy. Results: Majority of the subjects were single (77.84%), 1st born among their siblings (25.95%), belonged to low social class (50.63%), and unemployed(25.31%). The major risk factors were family history of illness (23.52%) and positive medical problem around birth (12.66%). The presence of family history of illness, positive medical problem around birth and advanced maternal age at birth were associated with early onset of epilepsy. Vulnerability for the epilepsy also increases among hospital deliveries. Conclusion: Although the present study has identified various risk factors, yet the results need to be further confirmed through case-control studies. (author)

  3. Contribution of radiodiagnosis to genetically significant dose

    International Nuclear Information System (INIS)

    Pele, J.M.; Ouvrard, R.

    Surveys were carried out in France on 33,000 X-ray medical examinations. The genetically significant dose to the whole population from roentgenography and fluoroscopy, for typical examinations, should be about 65mrads [fr

  4. Some conditions for significant contribution from photovoltaics to sustainable development

    International Nuclear Information System (INIS)

    Coiante, D.

    1994-03-01

    In medium-long term perspective, the anthropogenic atmospheric pollution, due to fossil fuel burning, could be contained by massively using of renewable energy. Significant improvements are expected to arise from diffusion into use of large scale PV power systems. Considering the situation in Italy as a typical study case, a limit can be individuated, which makes that PV contribution to annual electric energy balance can reach a maximum of about 7%. Such a figure corresponds to about 2% in terms of contribution to total energy balance. Thus, the intermittent energy sources are destined, in Italy, to be confined to a role, just significant (7%) in the electric energy sector, but quite marginal (2%) with reference to expected environmental massive benefits. Apart from numerical results, this disappointing concept can be applied in general to all OCSE countries, wich globally produce the largest amount of world pollutant energy. Consequently, if photovoltaics wants to acquire a real environmental consistence, the limit of PV system diffusion has to be overcome. This can be attained by implementing the present grid-tied reference model for PV system diffusion by including an hydrogen production and storage system

  5. Contribution of solar radiation to decadal temperature variability over land.

    Science.gov (United States)

    Wang, Kaicun; Dickinson, Robert E

    2013-09-10

    Global air temperature has become the primary metric for judging global climate change. The variability of global temperature on a decadal timescale is still poorly understood. This paper examines further one suggested hypothesis, that variations in solar radiation reaching the surface (Rs) have caused much of the observed decadal temperature variability. Because Rs only heats air during the day, its variability is plausibly related to the variability of diurnal temperature range (daily maximum temperature minus its minimum). We show that the variability of diurnal temperature range is consistent with the variability of Rs at timescales from monthly to decadal. This paper uses long comprehensive datasets for diurnal temperature range to establish what has been the contribution of Rs to decadal temperature variability. It shows that Rs over land globally peaked in the 1930s, substantially decreased from the 1940s to the 1970s, and changed little after that. Reduction of Rs caused a reduction of more than 0.2 °C in mean temperature during May to October from the 1940s through the 1970s, and a reduction of nearly 0.2 °C in mean air temperature during November to April from the 1960s through the 1970s. This cooling accounts in part for the near-constant temperature from the 1930s into the 1970s. Since then, neither the rapid increase in temperature from the 1970s through the 1990s nor the slowdown of warming in the early twenty-first century appear to be significantly related to changes of Rs.

  6. Significance of blood pressure variability in patients with sepsis.

    Science.gov (United States)

    Pandey, Nishant Raj; Bian, Yu-Yao; Shou, Song-Tao

    2014-01-01

    This study was undertaken to observe the characteristics of blood pressure variability (BPV) and sepsis and to investigate changes in blood pressure and its value on the severity of illness in patients with sepsis. Blood parameters, APACHE II score, and 24-hour ambulatory BP were analyzed in 89 patients with sepsis. In patients with APACHE II score>19, the values of systolic blood pressure (SBPV), diasystolic blood pressure (DBPV), non-dipper percentage, cortisol (COR), lactate (LAC), platelet count (PLT) and glucose (GLU) were significantly higher than in those with APACHE II score ≤19 (Pblood cell (WBC), creatinine (Cr), PaO2, C-reactive protein (CRP), adrenocorticotropic hormone (ACTH) and tumor necrosis factor α (TNF-α) were not statistically significant (P>0.05). Correlation analysis showed that APACHE II scores correlated significantly with SBPV and DBPV (P0.05). Logistic regression analysis of SBPV, DBPV, APACHE II score, and LAC was used to predict prognosis in terms of survival and non-survival rates. Receiver operating characteristics curve (ROC) showed that DBPV was a better predictor of survival rate with an AUC value of 0.890. However, AUC of SBPV, APACHE II score, and LAC was 0.746, 0.831 and 0.915, respectively. The values of SBPV, DBPV and non-dipper percentage are higher in patients with sepsis. DBPV and SBPV can be used to predict the survival rate of patients with sepsis.

  7. STEPWISE SELECTION OF VARIABLES IN DEA USING CONTRIBUTION LOADS

    Directory of Open Access Journals (Sweden)

    Fernando Fernandez-Palacin

    Full Text Available ABSTRACT In this paper, we propose a new methodology for variable selection in Data Envelopment Analysis (DEA. The methodology is based on an internal measure which evaluates the contribution of each variable in the calculation of the efficiency scores of DMUs. In order to apply the proposed method, an algorithm, known as “ADEA”, was developed and implemented in R. Step by step, the algorithm maximizes the load of the variable (input or output which contribute least to the calculation of the efficiency scores, redistributing the weights of the variables without altering the efficiency scores of the DMUs. Once the weights have been redistributed, if the lower contribution does not reach a previously given critical value, a variable with minimum contribution will be removed from the model and, as a result, the DEA will be solved again. The algorithm will stop when all variables reach a given contribution load to the DEA or until no more variables can be removed. In this way and contrary to what is usual, the algorithm provides a clear stop rule. In both cases, the efficiencies obtained from the DEA will be considered suitable and rightly interpreted in terms of the remaining variables, indicating the load themselves; moreover, the algorithm will provide a sequence of alternative nested models - potential solutions - that could be evaluated according to external criterion. To illustrate the procedure, we have applied the methodology proposed to obtain a research ranking of Spanish public universities. In this case, at each step of the algorithm, the critical value is obtained based on a simulation study.

  8. Significant Variables in the Combustion Process of Natural Gas

    OpenAIRE

    Villaflor, Gloria; Morales, Graciela V; Velasco, Jorge

    2008-01-01

    Se determinan las variables significativas del proceso de combustión de gas natural, aquellas más sensibles para producir cambios importantes desde punto de vista económico y medioambiental. Con este fin se realiza la simulación del proceso de combustión de gas natural, utilizando el simulador comercial HYSYS. Se determina que las variables de operación más sensibles para este proceso son la temperatura del aire, la temperatura de los gases de combustión y el exceso de aire usado en la combus...

  9. Value of Construction Company and its Dependence on Significant Variables

    Science.gov (United States)

    Vítková, E.; Hromádka, V.; Ondrušková, E.

    2017-10-01

    The paper deals with the value of the construction company assessment respecting usable approaches and determinable variables. The reasons of the value of the construction company assessment are different, but the most important reasons are the sale or the purchase of the company, the liquidation of the company, the fusion of the company with another subject or the others. According the reason of the value assessment it is possible to determine theoretically different approaches for valuation, mainly it concerns about the yield method of valuation and the proprietary method of valuation. Both approaches are dependant of detailed input variables, which quality will influence the final assessment of the company´s value. The main objective of the paper is to suggest, according to the analysis, possible ways of input variables, mainly in the form of expected cash-flows or the profit, determination. The paper is focused mainly on methods of time series analysis, regression analysis and mathematical simulation utilization. As the output, the results of the analysis on the case study will be demonstrated.

  10. Performance of healthcare organizations: contributing variables to efficiency and quality

    OpenAIRE

    Albuquerque, Isabel Garcia da Fonseca e Faro de

    2018-01-01

    The transition from volume-based healthcare to value-based healthcare has been the major challenge of National Health Systems. Nevertheless, some variables that might contribute to bring together healthcare professionals and healthcare challenges have been overlooked. Study A, the first of three studies, conducted in a primary healthcare setting, revealed that perceived and objective organizational performance is predicted by sense of community, which simultaneously mediates the relationship ...

  11. The variability of piezoelectric measurements. Material and measurement method contributions

    International Nuclear Information System (INIS)

    Stewart, M.; Cain, M.

    2002-01-01

    The variability of piezoelectric materials measurements has been investigated in order to separate the contributions from intrinsic instrumental variability, and the contributions from the variability in materials. The work has pinpointed several areas where weaknesses in the measurement methods result in high variability, and also show that good correlation between piezoelectric parameters allow simpler measurement methods to be used. The Berlincourt method has been shown to be unreliable when testing thin discs, however when testing thicker samples there is a good correlation between this and other methods. The high field permittivity and low field permittivity correlate well, so tolerances on low field measurements would predict high field performance. In trying to identify microstructural origins of samples that behave differently to others within a batch, no direct evidence was found to suggest that outliers originate from either differences in microstructure or crystallography. Some of the samples chosen as maximum outliers showed pin-holes, probably from electrical breakdown during poling, even though these defects would ordinarily be detrimental to piezoelectric output. (author)

  12. Significance of Demographic Variables for Targeting of Internet Advertisements

    Directory of Open Access Journals (Sweden)

    Václav Stříteský

    2016-06-01

    Full Text Available Broad ad targeting options belong among the major advantages of internet advertising. Demographic targeting has become a standard option in most of on-line advertising systems. There are more ways how to target on-line advertisements by using demographic variables. In some cases, e.g., social media, we can use data from user registrations. Modern technologies enable to estimate the demographic profile of internet users using on behavioural data. The traditional approach to the demographic targeting of advertisements based on affinity targeting assumes the existence of internet servers with sufficient homogeneity of visits. The aim of this article is to identify the differences in the internet content consumption habits of Czech internet users based on gender and age. The analysis is based on the data from the extensive research which was carried out by the Netmonitor project, and which was provided for the purposes of this study by the Association for Internet Development (SPIR. The research results show that the traditional affinity-based method of targeting according to gender and age is still suitable on the Czech internet. On the other hand, in some cases, the traditional approach of ad targeting based on affinity leads to wasted ad impressions that miss defined target group.

  13. Genetic Variants Contribute to Gene Expression Variability in Humans

    Science.gov (United States)

    Hulse, Amanda M.; Cai, James J.

    2013-01-01

    Expression quantitative trait loci (eQTL) studies have established convincing relationships between genetic variants and gene expression. Most of these studies focused on the mean of gene expression level, but not the variance of gene expression level (i.e., gene expression variability). In the present study, we systematically explore genome-wide association between genetic variants and gene expression variability in humans. We adapt the double generalized linear model (dglm) to simultaneously fit the means and the variances of gene expression among the three possible genotypes of a biallelic SNP. The genomic loci showing significant association between the variances of gene expression and the genotypes are termed expression variability QTL (evQTL). Using a data set of gene expression in lymphoblastoid cell lines (LCLs) derived from 210 HapMap individuals, we identify cis-acting evQTL involving 218 distinct genes, among which 8 genes, ADCY1, CTNNA2, DAAM2, FERMT2, IL6, PLOD2, SNX7, and TNFRSF11B, are cross-validated using an extra expression data set of the same LCLs. We also identify ∼300 trans-acting evQTL between >13,000 common SNPs and 500 randomly selected representative genes. We employ two distinct scenarios, emphasizing single-SNP and multiple-SNP effects on expression variability, to explain the formation of evQTL. We argue that detecting evQTL may represent a novel method for effectively screening for genetic interactions, especially when the multiple-SNP influence on expression variability is implied. The implication of our results for revealing genetic mechanisms of gene expression variability is discussed. PMID:23150607

  14. Assessing the role of internal climate variability in Antarctica's contribution to future sea-level rise

    Science.gov (United States)

    Tsai, C. Y.; Forest, C. E.; Pollard, D.

    2017-12-01

    The Antarctic ice sheet (AIS) has the potential to be a major contributor to future sea-level rise (SLR). Current projections of SLR due to AIS mass loss remain highly uncertain. Better understanding of how ice sheets respond to future climate forcing and variability is essential for assessing the long-term risk of SLR. However, the predictability of future climate is limited by uncertainties from emission scenarios, model structural differences, and the internal variability that is inherently generated within the fully coupled climate system. Among those uncertainties, the impact of internal variability on the AIS changes has not been explicitly assessed. In this study, we quantify the effect of internal variability on the AIS evolutions by using climate fields from two large-ensemble experiments using the Community Earth System Model to force a three-dimensional ice sheet model. We find that internal variability of climate fields, particularly atmospheric fields, among ensemble members leads to significantly different AIS responses. Our results show that the internal variability can cause about 80 mm differences of AIS contribution to SLR by 2100 compared to the ensemble-mean contribution of 380-450 mm. Moreover, using ensemble-mean climate fields as the forcing in the ice sheet model does not produce realistic simulations of the ice loss. Instead, it significantly delays the onset of retreat of the West Antarctic Ice Sheet for up to 20 years and significantly underestimates the AIS contribution to SLR by 0.07-0.11 m in 2100 and up to 0.34 m in the 2250's. Therefore, because the uncertainty caused by internal variability is irreducible, we seek to highlight a critical need to assess the role of internal variability in projecting the AIS loss over the next few centuries. By quantifying the impact of internal variability on AIS contribution to SLR, policy makers can obtain more robust estimates of SLR and implement suitable adaptation strategies.

  15. Relative Contributions of Socio-Cultural Variables to the Prediction ...

    African Journals Online (AJOL)

    Erah

    the Prediction of Maternal Mortality in Edo South. Senatorial ... variables across the two locations (rural and urban) was early marriage/early child bearing (R2 = 0.200;. F = 401.40 ... severe bleeding, infections, obstructed or prolonged .... Analytical System (SAS) mode. Descriptive .... incontinence of urine and faeces due to.

  16. Non-stationarities significantly distort short-term spectral, symbolic and entropy heart rate variability indices

    International Nuclear Information System (INIS)

    Magagnin, Valentina; Bassani, Tito; Bari, Vlasta; Turiel, Maurizio; Porta, Alberto; Maestri, Roberto; Pinna, Gian Domenico

    2011-01-01

    The autonomic regulation is non-invasively estimated from heart rate variability (HRV). Many methods utilized to assess autonomic regulation require stationarity of HRV recordings. However, non-stationarities are frequently present even during well-controlled experiments, thus potentially biasing HRV indices. The aim of our study is to quantify the potential bias of spectral, symbolic and entropy HRV indices due to non-stationarities. We analyzed HRV series recorded in healthy subjects during uncontrolled daily life activities typical of 24 h Holter recordings and during predetermined levels of robotic-assisted treadmill-based physical exercise. A stationarity test checking the stability of the mean and variance over short HRV series (about 300 cardiac beats) was utilized to distinguish stationary periods from non-stationary ones. Spectral, symbolic and entropy indices evaluated solely over stationary periods were contrasted with those derived from all the HRV segments. When indices were calculated solely over stationary series, we found that (i) during both uncontrolled daily life activities and controlled physical exercise, the entropy-based complexity indices were significantly larger; (ii) during uncontrolled daily life activities, the spectral and symbolic indices linked to sympathetic modulation were significantly smaller and those associated with vagal modulation were significantly larger; (iii) while during uncontrolled daily life activities, the variance of spectral, symbolic and entropy rate indices was significantly larger, during controlled physical exercise, it was smaller. The study suggests that non-stationarities increase the likelihood to overestimate the contribution of sympathetic control and affect the power of statistical tests utilized to discriminate conditions and/or groups

  17. Variability of Neuronal Responses: Types and Functional Significance in Neuroplasticity and Neural Darwinism.

    Science.gov (United States)

    Chervyakov, Alexander V; Sinitsyn, Dmitry O; Piradov, Michael A

    2016-01-01

    HIGHLIGHTS We suggest classifying variability of neuronal responses as follows: false (associated with a lack of knowledge about the influential factors), "genuine harmful" (noise), "genuine neutral" (synonyms, repeats), and "genuine useful" (the basis of neuroplasticity and learning).The genuine neutral variability is considered in terms of the phenomenon of degeneracy.Of particular importance is the genuine useful variability that is considered as a potential basis for neuroplasticity and learning. This type of variability is considered in terms of the neural Darwinism theory. In many cases, neural signals detected under the same external experimental conditions significantly change from trial to trial. The variability phenomenon, which complicates extraction of reproducible results and is ignored in many studies by averaging, has attracted attention of researchers in recent years. In this paper, we classify possible types of variability based on its functional significance and describe features of each type. We describe the key adaptive significance of variability at the neural network level and the degeneracy phenomenon that may be important for learning processes in connection with the principle of neuronal group selection.

  18. Contributing variables for sustainable livelihood status of the char women in Bangladesh

    Directory of Open Access Journals (Sweden)

    S. Al-Amin

    2012-03-01

    Full Text Available The main purpose of the study was to determine the contribution of variables to the sustainable livelihood status of char women. The sustainable livelihood status of a char woman was measured by computing a “sustainable livelihood status score” which is considering six major aspects of her livelihoods: food security, ability to provide family education, health and sanitation, shelter and family assets, clothing condition and social upliftment. Data were collected from 200 randomly selected char women by using interview schedule in two Upazilla of Jamalpur district in Bangladesh during November 2006 to March 2007. More than two-fifths (67.5 per cent of the char women were found under “medium sustainable livelihood status” compared to more than one-fifth (20.5 per cent of them belongs to ‘low sustainable livelihood status’ and only 12 per cent to “high sustainable livelihood status”. Pearson correlation test depicted that out of 16 variables, 13 had significant positive relationships with the sustainable livelihood status. Results of stepwise multiple regression analysis revealed that five variables namely, annual income, agricultural knowledge, income generating activities, family education and organizational participation contributed significantly which combindly explained 76.3 per cent of total variation to the sustainable livelihood status. Path analysis indicated that these variables had both direct and indirect effects to the sustainable livelihood status. Women who had more annual income, better agricultural knowledge, participation in income generating activities, more family education and more organizational participation were found to better sustainable livelihood status in char area. Government or concern other authorities need to give attention to these variables for any sustainable livelihood upliftment programme.

  19. Survey of French spine surgeons reveals significant variability in spine trauma practices in 2013.

    Science.gov (United States)

    Lonjon, G; Grelat, M; Dhenin, A; Dauzac, C; Lonjon, N; Kepler, C K; Vaccaro, A R

    2015-02-01

    In France, attempts to define common ground during spine surgery meetings have revealed significant variability in clinical practices across different schools of surgery and the two specialities involved in spine surgery, namely, neurosurgery and orthopaedic surgery. To objectively characterise this variability by performing a survey based on a fictitious spine trauma case. Our working hypothesis was that significant variability existed in trauma practices and that this variability was related to a lack of strong scientific evidence in spine trauma care. We performed a cross-sectional survey based on a clinical vignette describing a 31-year-old male with an L1 burst fracture and neurologic symptoms (numbness). Surgeons received the vignette and a 14-item questionnaire on the management of this patient. For each question, surgeons had to choose among five possible answers. Differences in answers across surgeons were assessed using the Index of Qualitative Variability (IQV), in which 0 indicates no variability and 1 maximal variability. Surgeons also received a questionnaire about their demographics and surgical experience. Of 405 invited spine surgeons, 200 responded to the survey. Five questions had an IQV greater than 0.9, seven an IQV between 0.5 and 0.9, and two an IQV lower than 0.5. Variability was greatest about the need for MRI (IQV=0.93), degree of urgency (IQV=0.93), need for fusion (IQV=0.92), need for post-operative bracing (IQV=0.91), and routine removal of instrumentation (IQV=0.94). Variability was lowest for questions about the need for surgery (IQV=0.42) and use of the posterior approach (IQV=0.36). Answers were influenced by surgeon specialty, age, experience level, and type of centre. Clinical practice regarding spine trauma varies widely in France. Little published evidence is available on which to base recommendations that would diminish this variability. Copyright © 2015. Published by Elsevier Masson SAS.

  20. Separating the contributions of variability and parameter uncertainty in probability distributions

    International Nuclear Information System (INIS)

    Sankararaman, S.; Mahadevan, S.

    2013-01-01

    This paper proposes a computational methodology to quantify the individual contributions of variability and distribution parameter uncertainty to the overall uncertainty in a random variable. Even if the distribution type is assumed to be known, sparse or imprecise data leads to uncertainty about the distribution parameters. If uncertain distribution parameters are represented using probability distributions, then the random variable can be represented using a family of probability distributions. The family of distributions concept has been used to obtain qualitative, graphical inference of the contributions of natural variability and distribution parameter uncertainty. The proposed methodology provides quantitative estimates of the contributions of the two types of uncertainty. Using variance-based global sensitivity analysis, the contributions of variability and distribution parameter uncertainty to the overall uncertainty are computed. The proposed method is developed at two different levels; first, at the level of a variable whose distribution parameters are uncertain, and second, at the level of a model output whose inputs have uncertain distribution parameters

  1. Reliability, validity, and significance of assessment of sense of contribution in the workplace.

    Science.gov (United States)

    Takaki, Jiro; Taniguchi, Toshiyo; Fujii, Yasuhito

    2014-01-29

    The purpose of this study was to assess the validity and reliability of the Sense of Contribution Scale (SCS), a newly developed, 7-item questionnaire used to measure sense of contribution in the workplace. Workers at 272 organizations answered questionnaires that included the SCS. Because of non-participation or missing data, the number of subjects included in the analyses for internal consistency and validity varied from 1,675 to 2,462 (response rates 54.6%-80.2%). Fifty-four workers were included in the analysis of test-retest reliability (response rate, 77.1%). The SCS showed high internal consistency (Cronbach's α coefficients in men and women were 0.85 and 0.86, respectively) and test-retest reliability (intraclass correlation coefficient = 0.91). Significant (p workplace bullying, and procedural and interactional justice. The SCS is a psychometrically satisfactory measure of sense of contribution in the workplace. The SCS provides a new and useful instrument to measure sense of contribution, which is independently associated with mental health in workers, for studies in organizational science, occupational health psychology and occupational medicine.

  2. European Randomized Study of Screening for Prostate Cancer Risk Calculator: External Validation, Variability, and Clinical Significance.

    Science.gov (United States)

    Gómez-Gómez, Enrique; Carrasco-Valiente, Julia; Blanca-Pedregosa, Ana; Barco-Sánchez, Beatriz; Fernandez-Rueda, Jose Luis; Molina-Abril, Helena; Valero-Rosa, Jose; Font-Ugalde, Pilar; Requena-Tapia, Maria José

    2017-04-01

    To externally validate the European Randomized Study of Screening for Prostate Cancer (ERSPC) risk calculator (RC) and to evaluate its variability between 2 consecutive prostate-specific antigen (PSA) values. We prospectively catalogued 1021 consecutive patients before prostate biopsy for suspicion of prostate cancer (PCa). The risk of PCa and significant PCa (Gleason score ≥7) from 749 patients was calculated according to ERSPC-RC (digital rectal examination-based version 3 of 4) for 2 consecutive PSA tests per patient. The calculators' predictions were analyzed using calibration plots and the area under the receiver operating characteristic curve (area under the curve). Cohen kappa coefficient was used to compare the ability and variability. Of 749 patients, PCa was detected in 251 (33.5%) and significant PCa was detected in 133 (17.8%). Calibration plots showed an acceptable parallelism and similar discrimination ability for both PSA levels with an area under the curve of 0.69 for PCa and 0.74 for significant PCa. The ERSPC showed 226 (30.2%) unnecessary biopsies with the loss of 10 significant PCa. The variability of the RC was 16% for PCa and 20% for significant PCa, and a higher variability was associated with a reduced risk of significant PCa. We can conclude that the performance of the ERSPC-RC in the present cohort shows a high similitude between the 2 PSA levels; however, the RC variability value is associated with a decreased risk of significant PCa. The use of the ERSPC in our cohort detects a high number of unnecessary biopsies. Thus, the incorporation of ERSPC-RC could help the clinical decision to carry out a prostate biopsy. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Reliability, Validity, and Significance of Assessment of Sense of Contribution in the Workplace

    Directory of Open Access Journals (Sweden)

    Jiro Takaki

    2014-01-01

    Full Text Available The purpose of this study was to assess the validity and reliability of the Sense of Contribution Scale (SCS, a newly developed, 7-item questionnaire used to measure sense of contribution in the workplace. Workers at 272 organizations answered questionnaires that included the SCS. Because of non-participation or missing data, the number of subjects included in the analyses for internal consistency and validity varied from 1,675 to 2,462 (response rates 54.6%–80.2%. Fifty-four workers were included in the analysis of test–retest reliability (response rate, 77.1%. The SCS showed high internal consistency (Cronbach’s α coefficients in men and women were 0.85 and 0.86, respectively and test–retest reliability (intraclass correlation coefficient = 0.91. Significant (p < 0.001, positive, moderate correlations were found between the SCS score and scores for organization-based self-esteem and work engagement in both genders, which support the SCS’s convergent and discriminant validity. The criterion validity of the SCS was supported by the finding that in both genders, the SCS scores were significantly (p < 0.05 and inversely associated with psychological distress and sleep disturbance in crude and in multivariable analyses that adjusted for demographics, organization-based self-esteem, work engagement, effort–reward ratio, workplace bullying, and procedural and interactional justice. The SCS is a psychometrically satisfactory measure of sense of contribution in the workplace. The SCS provides a new and useful instrument to measure sense of contribution, which is independently associated with mental health in workers, for studies in organizational science, occupational health psychology and occupational medicine.

  4. Evaluation of feedforward and feedback contributions to hand stiffness and variability in multijoint arm control.

    Science.gov (United States)

    He, Xin; Du, Yu-Fan; Lan, Ning

    2013-07-01

    The purpose of this study is to validate a neuromechanical model of the virtual arm (VA) by comparing emerging behaviors of the model to those of experimental observations. Hand stiffness of the VA model was obtained by either theoretical computation or simulated perturbations. Variability in hand position of the VA was generated by adding signal dependent noise (SDN) to the motoneuron pools of muscles. Reflex circuits of Ia, Ib and Renshaw cells were included to regulate the motoneuron pool outputs. Evaluation of hand stiffness and variability was conducted in simulations with and without afferent feedback under different patterns of muscle activations during postural maintenance. The simulated hand stiffness and variability ellipses captured the experimentally observed features in shape, magnitude and orientation. Steady state afferent feedback contributed significantly to the increase in hand stiffness by 35.75±16.99% in area, 18.37±7.80% and 16.15±7.15% in major and minor axes; and to the reduction of hand variability by 49.41±21.19% in area, 36.89±12.78% and 18.87±23.32% in major and minor axes. The VA model reproduced the neuromechanical behaviors that were consistent with experimental data, and it could be a useful tool for study of neural control of posture and movement, as well as for application to rehabilitation.

  5. An analytical approach to separate climate and human contributions to basin streamflow variability

    Science.gov (United States)

    Li, Changbin; Wang, Liuming; Wanrui, Wang; Qi, Jiaguo; Linshan, Yang; Zhang, Yuan; Lei, Wu; Cui, Xia; Wang, Peng

    2018-04-01

    Climate variability and anthropogenic regulations are two interwoven factors in the ecohydrologic system across large basins. Understanding the roles that these two factors play under various hydrologic conditions is of great significance for basin hydrology and sustainable water utilization. In this study, we present an analytical approach based on coupling water balance method and Budyko hypothesis to derive effectiveness coefficients (ECs) of climate change, as a way to disentangle contributions of it and human activities to the variability of river discharges under different hydro-transitional situations. The climate dominated streamflow change (ΔQc) by EC approach was compared with those deduced by the elasticity method and sensitivity index. The results suggest that the EC approach is valid and applicable for hydrologic study at large basin scale. Analyses of various scenarios revealed that contributions of climate change and human activities to river discharge variation differed among the regions of the study area. Over the past several decades, climate change dominated hydro-transitions from dry to wet, while human activities played key roles in the reduction of streamflow during wet to dry periods. Remarkable decline of discharge in upstream was mainly due to human interventions, although climate contributed more to runoff increasing during dry periods in the semi-arid downstream. Induced effectiveness on streamflow changes indicated a contribution ratio of 49% for climate and 51% for human activities at the basin scale from 1956 to 2015. The mathematic derivation based simple approach, together with the case example of temporal segmentation and spatial zoning, could help people understand variation of river discharge with more details at a large basin scale under the background of climate change and human regulations.

  6. Understanding the significance variables for fabrication of fish gelatin nanoparticles by Plackett-Burman design

    Science.gov (United States)

    Subara, Deni; Jaswir, Irwandi; Alkhatib, Maan Fahmi Rashid; Noorbatcha, Ibrahim Ali

    2018-01-01

    The aim of this experiment is to screen and to understand the process variables on the fabrication of fish gelatin nanoparticles by using quality-design approach. The most influencing process variables were screened by using Plackett-Burman design. Mean particles size, size distribution, and zeta potential were found in the range 240±9.76 nm, 0.3, and -9 mV, respectively. Statistical results explained that concentration of acetone, pH of solution during precipitation step and volume of cross linker had a most significant effect on particles size of fish gelatin nanoparticles. It was found that, time and chemical consuming is lower than previous research. This study revealed the potential of quality-by design in understanding the effects of process variables on the fish gelatin nanoparticles production.

  7. Significance of the impact of motion compensation on the variability of PET image features

    Science.gov (United States)

    Carles, M.; Bach, T.; Torres-Espallardo, I.; Baltas, D.; Nestle, U.; Martí-Bonmatí, L.

    2018-03-01

    In lung cancer, quantification by positron emission tomography/computed tomography (PET/CT) imaging presents challenges due to respiratory movement. Our primary aim was to study the impact of motion compensation implied by retrospectively gated (4D)-PET/CT on the variability of PET quantitative parameters. Its significance was evaluated by comparison with the variability due to (i) the voxel size in image reconstruction and (ii) the voxel size in image post-resampling. The method employed for feature extraction was chosen based on the analysis of (i) the effect of discretization of the standardized uptake value (SUV) on complementarity between texture features (TF) and conventional indices, (ii) the impact of the segmentation method on the variability of image features, and (iii) the variability of image features across the time-frame of 4D-PET. Thirty-one PET-features were involved. Three SUV discretization methods were applied: a constant width (SUV resolution) of the resampling bin (method RW), a constant number of bins (method RN) and RN on the image obtained after histogram equalization (method EqRN). The segmentation approaches evaluated were 40% of SUVmax and the contrast oriented algorithm (COA). Parameters derived from 4D-PET images were compared with values derived from the PET image obtained for (i) the static protocol used in our clinical routine (3D) and (ii) the 3D image post-resampled to the voxel size of the 4D image and PET image derived after modifying the reconstruction of the 3D image to comprise the voxel size of the 4D image. Results showed that TF complementarity with conventional indices was sensitive to the SUV discretization method. In the comparison of COA and 40% contours, despite the values not being interchangeable, all image features showed strong linear correlations (r  >  0.91, p\\ll 0.001 ). Across the time-frames of 4D-PET, all image features followed a normal distribution in most patients. For our patient cohort, the

  8. Pharmaceuticals occurrence in a WWTP with significant industrial contribution and its input into the river system

    International Nuclear Information System (INIS)

    Collado, N.; Rodriguez-Mozaz, S.; Gros, M.; Rubirola, A.; Barceló, D.; Comas, J.; Rodriguez-Roda, I.; Buttiglieri, G.

    2014-01-01

    Occurrence and removal of 81 representative Pharmaceutical Active Compounds (PhACs) were assessed in a municipal WWTP located in a highly industrialized area, with partial water reuse after UV tertiary treatment and discharge to a Mediterranean river. Water monitoring was performed in an integrated way at different points in the WWTP and river along three seasons. Consistent differences between therapeutic classes were observed in terms of influent concentration, removal efficiencies and seasonal variation. Conventional (primary and secondary) treatment was unable to completely remove numerous compounds and UV-based tertiary treatment played a complementary role for some of them. Industrial activity influence was highlighted in terms of PhACs presence and seasonal distribution. Even if global WWTP effluent impact on the studied river appeared to be minor, PhACs resulted widespread pollutants in river waters. Contamination can be particularly critical in summer in water scarcity areas, when water flow decreases considerably. -- Highlights: • Seasonal variation revealed a higher spring-summer removal compared to winter time. • Biological process was unable to provide a complete removal for most compounds. • UV-based tertiary treatment did play a complementary removal role for specific PhACs. • Diffuse river contamination and local WWTP contribution to it were observed. • River attenuation capacity is an important factor for removing most of the compounds. -- PhACs integrated WWTP-river data evaluation of coupled biological process and UV tertiary treatment in a WWTP with significant industrial contribution and in the receiving river waters

  9. The Little Engines That Could? Globular Clusters Contribute Significantly to Reionization-era Star Formation

    Science.gov (United States)

    Boylan-Kolchin, Michael

    2018-06-01

    Metal-poor globular clusters (GCs) are both numerous and ancient, which indicates that they may be important contributors to ionizing radiation in the reionization era. Starting from the observed number density and stellar mass function of old GCs at z = 0, I compute the contribution of GCs to ultraviolet luminosity functions (UVLFs) in the high-redshift Universe (10 ≳ z ≳ 4). Even under absolutely minimal assumptions - no disruption of GCs and no reduction in GC stellar mass from early times to the present - GC star formation contributes non-negligibly to the UVLF at luminosities that are accessible to the Hubble Space Telescope (HST; M1500 ≈ -17). If the stellar masses of GCs were significantly higher in the past, as is predicted by most models explaining GC chemical anomalies, then GCs dominate the UV emission from many galaxies in existing deep-field observations. On the other hand, it is difficult to reconcile observed UVLFs with models requiring stellar masses at birth that exceed present-day stellar masses by more than a factor of 5. The James Webb Space Telescope (JWST) will be able to directly detect individual GCs at z ˜ 6 in essentially all bright galaxies, and many galaxies below the knee of the UVLF, for most of the scenarios considered here. The properties of a subset of high-redshift sources with -19 ≲ M_{1500} ≲ -14 in HST lensing fields indicate that they may actually be GCs in formation.

  10. Trends in seasonal warm anomalies across the contiguous United States: Contributions from natural climate variability

    Science.gov (United States)

    Lejiang Yu; Shiyuan Zhong; Warren E. Heilman; Xindi. Bian

    2018-01-01

    Many studies have shown the importance of anthropogenic greenhouse gas emissions in contributing to observed upward trends in the occurrences of temperature extremes over the U.S. However, few studies have investigated the contributions of internal variability in the climate system to these observed trends. Here we use daily maximum temperature time series from the...

  11. Do health care workforce, population, and service provision significantly contribute to the total health expenditure? An econometric analysis of Serbia.

    Science.gov (United States)

    Santric-Milicevic, M; Vasic, V; Terzic-Supic, Z

    2016-08-15

    In times of austerity, the availability of econometric health knowledge assists policy-makers in understanding and balancing health expenditure with health care plans within fiscal constraints. The objective of this study is to explore whether the health workforce supply of the public health care sector, population number, and utilization of inpatient care significantly contribute to total health expenditure. The dependent variable is the total health expenditure (THE) in Serbia from the years 2003 to 2011. The independent variables are the number of health workers employed in the public health care sector, population number, and inpatient care discharges per 100 population. The statistical analyses include the quadratic interpolation method, natural logarithm and differentiation, and multiple linear regression analyses. The level of significance is set at P Total health expenditure increased by 1.21 standard deviations, with an increase in health workforce growth rate by 1 standard deviation. Furthermore, this rate decreased by 1.12 standard deviations, with an increase in (negative) population growth rate by 1 standard deviation. Finally, the growth rate increased by 0.38 standard deviation, with an increase of the growth rate of inpatient care discharges per 100 population by 1 standard deviation (P < 0.001). Study results demonstrate that the government has been making an effort to control strongly health budget growth. Exploring causality relationships between health expenditure and health workforce is important for countries that are trying to consolidate their public health finances and achieve universal health coverage at the same time.

  12. LASR-Guided Variability Subtraction: The Linear Algorithm for Significance Reduction of Stellar Seismic Activity

    Science.gov (United States)

    Horvath, Sarah; Myers, Sam; Ahlers, Johnathon; Barnes, Jason W.

    2017-10-01

    Stellar seismic activity produces variations in brightness that introduce oscillations into transit light curves, which can create challenges for traditional fitting models. These oscillations disrupt baseline stellar flux values and potentially mask transits. We develop a model that removes these oscillations from transit light curves by minimizing the significance of each oscillation in frequency space. By removing stellar variability, we prepare each light curve for traditional fitting techniques. We apply our model to $\\delta$-Scuti KOI-976 and demonstrate that our variability subtraction routine successfully allows for measuring bulk system characteristics using traditional light curve fitting. These results open a new window for characterizing bulk system parameters of planets orbiting seismically active stars.

  13. Biological variability in biomechanical engineering research: Significance and meta-analysis of current modeling practices.

    Science.gov (United States)

    Cook, Douglas; Julias, Margaret; Nauman, Eric

    2014-04-11

    Biological systems are characterized by high levels of variability, which can affect the results of biomechanical analyses. As a review of this topic, we first surveyed levels of variation in materials relevant to biomechanics, and compared these values to standard engineered materials. As expected, we found significantly higher levels of variation in biological materials. A meta-analysis was then performed based on thorough reviews of 60 research studies from the field of biomechanics to assess the methods and manner in which biological variation is currently handled in our field. The results of our meta-analysis revealed interesting trends in modeling practices, and suggest a need for more biomechanical studies that fully incorporate biological variation in biomechanical models and analyses. Finally, we provide some case study example of how biological variability may provide valuable insights or lead to surprising results. The purpose of this study is to promote the advancement of biomechanics research by encouraging broader treatment of biological variability in biomechanical modeling. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Human Sterol Regulatory Element-Binding Protein 1a Contributes Significantly to Hepatic Lipogenic Gene Expression

    Directory of Open Access Journals (Sweden)

    Andreas Bitter

    2015-01-01

    Full Text Available Background/Aims: Sterol regulatory element-binding protein (SREBP 1, the master regulator of lipogenesis, was shown to be associated with non-alcoholic fatty liver disease, which is attributed to its major isoform SREBP1c. Based on studies in mice, the minor isoform SREBP1a is regarded as negligible for hepatic lipogenesis. This study aims to elucidate the expression and functional role of SREBP1a in human liver. Methods: mRNA expression of both isoforms was quantified in cohorts of human livers and primary human hepatocytes. Hepatocytes were treated with PF-429242 to inhibit the proteolytic activation of SREBP precursor protein. SREBP1a-specifc and pan-SREBP1 knock-down were performed by transfection of respective siRNAs. Lipogenic SREBP-target gene expression was analyzed by real-time RT-PCR. Results: In human liver, SREBP1a accounts for up to half of the total SREBP1 pool. Treatment with PF-429242 indicated SREBP-dependent auto-regulation of SREBP1a, which however was much weaker than of SREBP1c. SREBP1a-specifc knock-down also reduced significantly the expression of SREBP1c and of SREBP-target genes. Regarding most SREBP-target genes, simultaneous knock-down of both isoforms resulted in effects of only similar extent as SREBP1a-specific knock-down. Conclusion: We here showed that SREBP1a is significantly contributing to the human hepatic SREBP1 pool and has a share in human hepatic lipogenic gene expression.

  15. Contributions of internal climate variability to mitigation of projected future regional sea level rise

    Science.gov (United States)

    Hu, A.; Bates, S. C.

    2017-12-01

    Observations indicate that the global mean surface temperature is rising, so does the global mean sea level. Sea level rise (SLR) can impose significant impacts on island and coastal communities, especially when SLR is compounded with storm surges. Here, via analyzing results from two sets of ensemble simulations from the Community Earth System Model version 1, we investigate how the potential SLR benefits through mitigating the future emission scenarios from business as usual to a mild-mitigation over the 21st Century would be affected by internal climate variability. Results show that there is almost no SLR benefit in the near term due to the large SLR variability due to the internal ocean dynamics. However, toward the end of the 21st century, the SLR benefit can be as much as a 26±1% reduction of the global mean SLR due to seawater thermal expansion. Regionally, the benefits from this mitigation for both near and long terms are heterogeneous. They vary from just a 11±5% SLR reduction in Melbourne, Australia to a 35±6% reduction in London. The processes contributing to these regional differences are the coupling of the wind-driven ocean circulation with the decadal scale sea surface temperature mode in the Pacific and Southern Oceans, and the changes of the thermohaline circulation and the mid-latitude air-sea coupling in the Atlantic.

  16. Identification of significant process variables for a flow-through supercritical water oxidation reactor

    International Nuclear Information System (INIS)

    Rossi, R.E.

    1992-05-01

    The effects of four process variables on the destruction efficiency of a flow-through supercritical water oxidation reactor were investigated. These process variables included: (1) reactor throughput (GPH), (2) concentration of the surrogate waste (% acetone), (3) maximum reactor tube-wall temperature (OC), and (4) applied stoichiometric oxygen. The analysis was conducted utilizing two-level factorial experiments, steepest ascent methods, and central composite designs. This experimental protocol assures efficient experimentation and allows for an empirical response surface model of the system to be developed. This experimentation identified a significant positive effect for stoichiometric oxygen applied and temperature variations between 400 to 500 degrees C. The increase in destruction efficiency due to stoichiometric 0 2 provides strong evidence that supercritical water oxidations are catalyzed by excess oxygen, and the strong temperature effect is a result of large increases in the kinetic rates for this temperature range. However, increasing temperature between 550 to 650 degrees C does not provide substantial increases in destruction efficiency. In addition, destruction efficiency is significantly unproved by increasing the Reynolds number and residence time. The destruction efficiency of the reactor is also dependent upon the initial concentration of surrogate waste. This concentration dependence may indicate first-order supercritical CO kinetics is inadequate for describing all waste types and reactor configurations. Alternatively, it may indicate reactant mixing, caused by local turbulence at the oxidation fronts of these higher concentration waste streams, results in higher destruction efficiencies

  17. Contribution of geodiversity, climate and spatial variables for biodiversity across a gradient of human influence

    Science.gov (United States)

    Tukiainen, Helena; Alahuhta, Janne; Ala-Hulkko, Terhi; Field, Richard; Lampinen, Raino; Hjort, Jan

    2016-04-01

    Implementation of geodiversity may provide new perspectives for nature conservation. The relation between geodiversity and biodiversity has been established in recent studies but remains underexplored in environments with high human pressure. In this study, we explored the effect of geodiversity (i.e. geological, hydrological and geomorphological diversity), climate and spatial variables on biodiversity (vascular plant species richness) in environments with different human impact. The study area ranged trough the boreal vegetation zone in Finland and included altogether 1401 1-km2 grid cells from urban, rural and natural environments. The contribution of environmental variable groups for species diversity in different environments was statistically analyzed with variation partitioning method. According to the results, the contribution of geodiversity decreased and the contribution of climate and spatial variables increased as the land use became more human-induced. Hence, the connection between geodiversity and species richness was most pronounced in natural state environments.

  18. Variability in anatomical features of human clavicle: Its forensic anthropological and clinical significance

    Directory of Open Access Journals (Sweden)

    Jagmahender Singh Sehrawat

    2016-06-01

    Full Text Available Bones can reflect the basic framework of human body and may provide valuable information about the biological identity of the deceased. They, often, survive the morphological alterations, taphonomic destructions, decay/mutilation and decomposition insults. In-depth knowledge of variations in clavicular shape, size and its dimensions is very important from both clinical (fixation of clavicular fractures using external or inter-medullary devices, designing orthopedic fixation devices as well as forensic anthropological perspectives. Human clavicle is the most frequently fractured bone of human skeleton, possessing high degree of variability in its anatomical, biomechanical and morphological features. Extended period of skeletal growth (up to third decade in clavicle imparts it an additional advantage for forensic identification purposes. In present study, five categories of clavicular features like lengths, diameters, angles, indices and robustness were examined to explore the suitability of collarbone for forensic and clinical purposes. For this purpose, 263 pairs of adult clavicles (195 Males and 68 Females were collected from autopsied cadavers and were studied for 13 anatomical features. Gender and occupational affiliations of cadavers were found to have significant influences on anatomical dimensions of their clavicles. Product index, weight and circumference of collarbone were found the best univariate variables, discriminating sex of more than 80% individuals. The best multivariate Function-I (DF: -17.315 + 0.054 CL-L+0.196 CC-R+0.184 DM-L could identify sex and occupation of 89.4% (89.2% Male and 89.7% Female and 65.4% individuals, respectively. All clavicular variables were found bilaterally asymmetric; left clavicles being significantly longer in length, lighter in weight, smooth in texture and less curved than the right side bones. Among non-metric traits, sub-clavian groove, nutrient foramina and ‘type’ of clavicle exhibited

  19. Interallelic class switch recombination contributes significantly to class switching in mouse B cells.

    Science.gov (United States)

    Reynaud, Stéphane; Delpy, Laurent; Fleury, Laurence; Dougier, Hei-Lanne; Sirac, Christophe; Cogné, Michel

    2005-05-15

    Except for the expression of IgM and IgD, DNA recombination is constantly needed for the expression of other Ig classes and subclasses. The predominant path of class switch recombination (CSR) is intrachromosomal, and the looping-out and deletion model has been abundantly documented. However, switch regions also occasionally constitute convenient substrates for interchromosomal recombination, since it is noticeably the case in a number of chromosomal translocations causing oncogene deregulation in the course of lymphoma and myeloma. Although asymmetric accessibility of Ig alleles should theoretically limit its occurrence, interallelic CSR was shown to occur at low levels during IgA switching in rabbit, where the definition of allotypes within both V and C regions helped identify interchromosomally derived Ig. Thus, we wished to evaluate precisely interallelic CSR frequency in mouse B cells, by using a system in which only one allele (of b allotype) could express a functional VDJ region, whereas only interallelic CSR could restore expression of an excluded (a allotype) allele. In our study, we show that interchromosomal recombination of V(H) and Cgamma or Calpha occurs in vivo in B cells at a frequency that makes a significant contribution to physiological class switching: trans-association of V(H) and C(H) genes accounted for 7% of all alpha mRNA, and this frequency was about twice higher for the gamma3 transcripts, despite the much shorter distance between the J(H) region and the Cgamma3 gene, thus confirming that this phenomenon corresponded to site-specific switching and not to random recombination between long homologous loci.

  20. Visuomotor contribution to force variability in the plantarflexor and dorsiflexor muscles

    OpenAIRE

    Tracy, Brian L.

    2007-01-01

    The visual correction employed during isometric contractions of large proximal muscles contributes variability to the descending command and alters fluctuations in muscle force. This study explored the contribution of visuomotor correction to isometric force fluctuations for the more distal dorsiflexor (DF) and plantarflexor (PF) muscles of the ankle. Twenty-one healthy adults performed steady isometric contractions with the DF and PF muscles both with (VIS) and without (NOVIS) visual feedbac...

  1. Do motor control genes contribute to interindividual variability in decreased movement in patients with pain?

    Directory of Open Access Journals (Sweden)

    Mishra Bikash K

    2007-07-01

    Full Text Available Abstract Background Because excessive reduction in activities after back injury may impair recovery, it is important to understand and address the factors contributing to the variability in motor responses to pain. The current dominant theory is the "fear-avoidance model", in which the some patients' heightened fears of further injury cause them to avoid movement. We propose that in addition to psychological factors, neurochemical variants in the circuits controlling movement and their modification by pain may contribute to this variability. A systematic search of the motor research literature and genetic databases yielded a prioritized list of polymorphic motor control candidate genes. We demonstrate an analytic method that we applied to 14 of these genes in 290 patients with acute sciatica, whose reduction in movement was estimated by items from the Roland-Morris Disability Questionnaire. Results We genotyped a total of 121 single nucleotide polymorphisms (SNPs in 14 of these genes, which code for the dopamine D2 receptor, GTP cyclohydrolase I, glycine receptor α1 subunit, GABA-A receptor α2 subunit, GABA-A receptor β1 subunit, α-adrenergic 1C, 2A, and 2C receptors, serotonin 1A and 2A receptors, cannabinoid CB-1 receptor, M1 muscarinic receptor, and the tyrosine hydroxylase, and tachykinin precursor-1 molecules. No SNP showed a significant association with the movement score after a Bonferroni correction for the 14 genes tested. Haplotype analysis of one of the blocks in the GABA-A receptor β1 subunit showed that a haplotype of 11% frequency was associated with less limitation of movement at a nominal significance level value (p = 0.0025 almost strong enough to correct for testing 22 haplotype blocks. Conclusion If confirmed, the current results may suggest that a common haplotype in the GABA-A β1 subunit acts like an "endogenous muscle relaxant" in an individual with subacute sciatica. Similar methods might be applied a larger set of

  2. [The nurse's thought for a significant social contribution by the production and use of scientific knowledge].

    Science.gov (United States)

    Pépin, Jacinthe

    2015-06-01

    The social contribution of nurses to the health of the population is mainly defined by the knowledge supporting their actions. Conceptualization in nursing guides the production and utilisation of scientific knowledge within the discipline. The purpose of this paper is to present the recent thoughts on nursing theory and to provide some strategies to integrate them within the activities of knowledge mobilization, in practice, research, and education. When nurses are engaged in mobilizing theoretical and empirical knowledge in answering nursing practice questions and in discussing social health issues, they participate in persons, families, and communities health improvement, while affirming their disciplinary and social identity. Called to be change agents in health care systems, with other professional team members, it is important that nurses be prepared to mobilize knowledge and to engage in critical reasoning, and ethical conduct. Their social contribution will be as strong as the value they assign to nursing knowledge and their participation in producing it.

  3. [THE SIGNIFICANCE OF THE LEGAL PERSPECTIVE - THE LEGAL WORLD'S CONTRIBUTION TO THE MEDICAL WORLD].

    Science.gov (United States)

    Sigler-Harcavi, Alona; Cohen Ashkenazi, Limor

    2018-04-01

    Working with medical and paramedical teams has taught us that the medical staff does not fully utilize the potential of judicial decisions and precedents as a source for learning, drawing conclusions and motivating progress. Judicial ruling is an essential part of the toolbox used by medical administrators in general, and healthcare risk managers in particular. Knowing the relevant legal rulings, before you embark on any given path, is the equivalent of looking before you leap. This is not necessarily an issue of "holy scripture", but should mainly be considered as a source for expanding your perspective. Knowledge of the relevant rulings has many advantages that stem from the unique characteristics of the legal system. While the medical world has a clear and unequivocal advantage regarding knowledge and experience with respect to medicine, the legal world has various other advantages: a different and wider perspective with respect to economic and/or political considerations; universal fundamental principles, such as autonomy, equality, distributive justice, human dignity, the state's obligations to its citizens; complex systems of checks and balances, such as: desirable vs. available, the benefit of few vs. the good of the many, etc. These tools, typical of the legal world, are especially relevant to medicolegal issues, usually associated with medical administration, such as: the obligation of consultation, obligation of follow-up, treatment continuity, priorities, resource distribution, patient rights, etc. The contribution of the legal world to these issues is both unique and essential. Those who question the ability of judges to understand the medical world and to materially contribute to medical thinking and practice, claiming that they lack medical training and experience, should recognize the diverse contribution of the legal world to the medical world.

  4. Fragrance mix II in the baseline series contributes significantly to detection of fragrance allergy

    DEFF Research Database (Denmark)

    Heisterberg, Maria S Vølund; Andersen, Klaus E.; Avnstorp, Christian

    2010-01-01

    Background: Fragrance mix II (FM II) is a relatively new screening marker for fragrance contact allergy. It was introduced in the patch test baseline series in Denmark in 2005 and contains six different fragrance chemicals commonly present in cosmetic products and which are known allergens. Aim......: To investigate the diagnostic contribution of including FM II in the baseline series by comparing it with other screening markers of fragrance allergy: fragrance mix I (FM I), Myroxylon pereirae and hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC). Method: Retrospective study of 12 302 patients consecutively...

  5. Temporal variability of antibiotics fluxes in wastewater and contribution from hospitals.

    Directory of Open Access Journals (Sweden)

    Sylvain Coutu

    Full Text Available Significant quantities of antibiotics are used in all parts of the globe to treat diseases with bacterial origins. After ingestion, antibiotics are excreted by the patient and transmitted in due course to the aquatic environment. This study examined temporal fluctuations (monthly time scale in antibiotic sources (ambulatory sales and data from a hospital dispensary for Lausanne, Switzerland. Source variability (i.e., antibiotic consumption, monthly data for 2006-2010 were examined in detail for nine antibiotics--azithromycin, ciprofloxacin, clarithromycin, clindamycin, metronidazole, norfloxacin, ofloxacin, sulfamethoxazole and trimethoprim, from which two main conclusions were reached. First, some substances--azithromycin, clarithromycin, ciprofloxacin--displayed high seasonality in their consumption, with the winter peak being up to three times higher than the summer minimum. This seasonality in consumption resulted in seasonality in Predicted Environmental Concentrations (PECs. In addition, the seasonality in PECs was also influenced by that in the base wastewater flow. Second, the contribution of hospitals to the total load of antibiotics reaching the Lausanne Wastewater Treatment Plant (WTP fluctuated markedly on a monthly time scale, but with no seasonal pattern detected. That is, there was no connection between fluctuations in ambulatory and hospital consumption for the substances investigated.

  6. Seasonal and spatial variability of surface ozone over China: contributions from background and domestic pollution

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2011-04-01

    Full Text Available Both observations and a 3-D chemical transport model suggest that surface ozone over populated eastern China features a summertime trough and that the month when surface ozone peaks differs by latitude and region. Source-receptor analysis is used to quantify the contributions of background ozone and Chinese anthropogenic emissions on this variability. Annual mean background ozone over China shows a spatial gradient from 55 ppbv in the northwest to 20 ppbv in the southeast, corresponding with changes in topography and ozone lifetime. Pollution background ozone (annual mean of 12.6 ppbv shows a minimum in the summer and maximum in the spring. On the monthly-mean basis, Chinese pollution ozone (CPO has a peak of 20–25 ppbv in June north of the Yangtze River and in October south of it, which explains the peaks of surface ozone in these months. The summertime trough in surface ozone over eastern China can be explained by the decrease of background ozone from spring to summer (by −15 ppbv regionally averaged over eastern China. Tagged simulations suggest that long-range transport of ozone from northern mid-latitude continents (including Europe and North America reaches a minimum in the summer, whereas ozone from Southeast Asia exhibits a maximum in the summer over eastern China. This contrast in seasonality provides clear evidence that the seasonal switch in monsoonal wind patterns plays a significant role in determining the seasonality of background ozone over China.

  7. Contextual Variability in Personality from Significant-Other Knowledge and Relational Selves

    Directory of Open Access Journals (Sweden)

    Susan M Andersen

    2016-01-01

    Full Text Available We argue that the self is intrinsically embedded in an interpersonal context such that it varies in IF-THEN terms, as the relational self. We have demonstrated that representations of the significant other and the relationship with that other are automatically activated by situational cues and that this activation affects both experienced and expressed aspects of the self and personality. Here, we expand on developments of the IF–THEN cognitive-affective framework of personality (CAPS, Mischel & Shoda, 1995, by extending it to the domain of interpersonal relationships at the dyadic level (Andersen & Chen, 2002. Going beyond Mischel’s early research (Mischel, 1968, our framework combines social cognition and learning theory with a learning-based psychodynamic approach, which provides the basis for extensive research on the social-cognitive process of transference and the relational self as it arises in everyday social interactions (Andersen & Cole, 1990, evidence from which contributes to a modern conceptualization of personality that emphasizes the centrality of the situation.

  8. Contextual Variability in Personality From Significant-Other Knowledge and Relational Selves.

    Science.gov (United States)

    Andersen, Susan M; Tuskeviciute, Rugile; Przybylinski, Elizabeth; Ahn, Janet N; Xu, Joy H

    2015-01-01

    We argue that the self is intrinsically embedded in an interpersonal context such that it varies in IF-THEN terms, as the relational self. We have demonstrated that representations of the significant other and the relationship with that other are automatically activated by situational cues and that this activation affects both experienced and expressed aspects of the self and personality. Here, we expand on developments of the IF-THEN cognitive-affective framework of personality system (Mischel and Shoda, 1995), by extending it to the domain of interpersonal relationships at the dyadic level (Andersen and Chen, 2002). Going beyond Mischel's early research (Mischel, 1968), our framework combines social cognition and learning theory with a learning-based psychodynamic approach, which provides the basis for extensive research on the social-cognitive process of transference and the relational self as it arises in everyday social interactions (Andersen and Cole, 1990), evidence from which contributes to a modern conceptualization of personality that emphasizes the centrality of the situation.

  9. Geological subsurface will contribute significantly to the implementation of the energy policy towards renewables in Germany

    Science.gov (United States)

    Martens, Sonja; Kühn, Michael

    2015-04-01

    The demands to exploit the geological subsurface are increasing. In addition to the traditional production of raw materials such as natural gas and petroleum, or potable groundwater extraction the underground will most likely also be used to implement the climate and energy policy objectives in the context of the energy transition to renewables. These include the storage of energy from renewable sources (e.g. hydrogen and methane), the use of geothermal energy and possibly the long-term storage of carbon dioxide to reduce the release of greenhouse gases into the atmosphere. The presentation addresses the question which realistic contribution can be expected from the geo-resource subsurface for the energy revolution, the detachment of fossil and nuclear fuels as well as the reduction of CO2 emissions. The study of Henning and Palzer [1] that models the energy balance of the electricity and heat sector including all renewable energy converters, storage components and loads for a future German energy system shows that provision with 100% renewables is economically feasible by 2050. Based on their work, our estimates underline that already in 2015 more than 100% of the required methane storage capacities therein are available and more than 100% of the heat pump demands might be covered by shallow and deep geothermal energy production in the future. In addition we show that a newly developed energy storage system [2-3] could be applied to store 20-60% of the surplus energy from renewables expected for 2050 with integrated gas storage of methane and CO2. [1] Henning H-M, Palzer A (2014) A comprehensive model for the German electricity and heat sector in a future energy system with a dominant contribution from renewable energy technologies -- Part I: Methodology. Renewable and Sustainable Energy Reviews 30, 1003-1018. doi: 10.1016/j.rser.2013.09.012 [2] Kühn M, Nakaten N, Streibel M, Kempka T (2014) CO2 geological storage and utilization for a carbon neutral "power

  10. Significant Contributions of the Albrecht's A Term to Nonresonant Raman Scattering Processes.

    Science.gov (United States)

    Gong, Zu-Yong; Tian, Guangjun; Duan, Sai; Luo, Yi

    2015-11-10

    The Raman intensity can be well described by the famous Albrecht's Raman theory that consists of A and B terms. It is well-known that the contribution from Albrecht's A term can be neglected without any loss of accuracy for far-off resonant Raman scattering processes. However, as demonstrated in this study, we have found that this widely accepted long-standing assumption fails drastically for totally symmetric vibration modes of molecules in general off-resonant Raman scattering. Perturbed first-principles calculations for water molecule show that strong constructive interference between the A and B terms occurs for the Raman intensity of the symmetric O-H stretching mode, which can account for ∼40% of the total intensity. Meanwhile, a minor destructive interference is found for the angle bending mode. The state-to-state mapping between Albrecht's theory and perturbation theory allows us to verify the accuracy of the widely employed perturbation method for the dynamic/resonant Raman intensities. The model calculations rationalized from water molecule with the bending mode show that the perturbation method is a good approximation only when the absolute energy difference between the first excited state and the incident light is more than five times greater than the vibrational energy in the ground state.

  11. On the significance of bell's inequality for hidden-variable theories

    International Nuclear Information System (INIS)

    De Baere, W.

    1984-01-01

    It is explicitly shown that Bell's derivation of the generalized Bell inequality and its subsequent interpretation depend on an implicit hypothesis concerning the reproducibility of some set of hidden variables in different runs of the same experiment

  12. Contribution of execution noise to arm movement variability in three-dimensional space.

    Science.gov (United States)

    Apker, Gregory A; Buneo, Christopher A

    2012-01-01

    Reaching movements are subject to noise associated with planning and execution, but precisely how these noise sources interact to determine patterns of endpoint variability in three-dimensional space is not well understood. For frontal plane movements, variability is largest along the depth axis (the axis along which visual planning noise is greatest), with execution noise contributing to this variability along the movement direction. Here we tested whether these noise sources interact in a similar way for movements directed in depth. Subjects performed sequences of two movements from a single starting position to targets that were either both contained within a frontal plane ("frontal sequences") or where the first was within the frontal plane and the second was directed in depth ("depth sequences"). For both sequence types, movements were performed with or without visual feedback of the hand. When visual feedback was available, endpoint distributions for frontal and depth sequences were generally anisotropic, with the principal axes of variability being strongly aligned with the depth axis. Without visual feedback, endpoint distributions for frontal sequences were relatively isotropic and movement direction dependent, while those for depth sequences were similar to those with visual feedback. Overall, the results suggest that in the presence of visual feedback, endpoint variability is dominated by uncertainty associated with planning and updating visually guided movements. In addition, the results suggest that without visual feedback, increased uncertainty in hand position estimation effectively unmasks the effect of execution-related noise, resulting in patterns of endpoint variability that are highly movement direction dependent.

  13. Clinical significance of mobile health assessed sleep duration and variability in bipolar disorder.

    Science.gov (United States)

    Kaufmann, Christopher N; Gershon, Anda; Eyler, Lisa T; Depp, Colin A

    2016-10-01

    Sleep disturbances are prevalent, persistent, and impairing features of bipolar disorder. However, the near-term and cumulative impact of the severity and variability of sleep disturbances on symptoms and functioning remains unclear. We examined self-reported daily sleep duration and variability in relation to mood symptoms, medication adherence, cognitive functioning, and concurrent daily affect. Forty-one outpatients diagnosed with bipolar disorder were asked to provide daily reports of sleep duration and affect collected via ecological momentary assessment with smartphones over eleven weeks. Measures of depressive and manic symptoms, medication adherence, and cognitive function were collected at baseline and concurrent assessment of affect were collected daily. Analyses examined whether sleep duration or variability were associated with baseline measures and changes in same-day or next-day affect. Greater sleep duration variability (but not average sleep duration) was associated with greater depressive and manic symptom severity, and lower medication adherence at baseline, and with lower and more variable ratings of positive affect and higher ratings of negative affect. Sleep durations shorter than 7-8 h were associated with lower same-day ratings of positive and higher same-day ratings of negative affect, however this did not extend to next-day affect. Greater cumulative day-to-day sleep duration variability, but not average sleep duration, was related to more severe mood symptoms, lower self-reported medication adherence and higher levels of negative affect. Bouts of short- or long-duration sleep had transient impact on affect. Day-to-day sleep variability may be important to incorporate into clinical assessment of sleep disturbances in bipolar disorder. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Genetic variation in VEGF does not contribute significantly to the risk of congenital cardiovascular malformation.

    Directory of Open Access Journals (Sweden)

    Helen R Griffin

    Full Text Available Several previous studies have investigated the role of common promoter variants in the vascular endothelial growth factor (VEGF gene in causing congenital cardiovascular malformation (CVM. However, results have been discrepant between studies and no study to date has comprehensively characterised variation throughout the gene. We genotyped 771 CVM cases, of whom 595 had the outflow tract malformation Tetralogy of Fallot (TOF, and carried out TDT and case-control analyses using haplotype-tagging SNPs in VEGF. We carried out a meta-analysis of previous case-control or family-based studies that had typed VEGF promoter SNPs, which included an additional 570 CVM cases. To identify rare variants potentially causative of CVM, we carried out mutation screening in all VEGF exons and splice sites in 93 TOF cases. There was no significant effect of any VEGF haplotype-tagging SNP on the risk of CVM in our analyses of 771 probands. When the results of this and all previous studies were combined, there was no significant effect of the VEGF promoter SNPs rs699947 (OR 1.05 [95% CI 0.95-1.17]; rs1570360 (OR 1.17 [95% CI 0.99-1.26]; and rs2010963 (OR 1.04 [95% CI 0.93-1.16] on the risk of CVM in 1341 cases. Mutation screening of 93 TOF cases revealed no VEGF coding sequence variants and no changes at splice consensus sequences. Genetic variation in VEGF appears to play a small role, if any, in outflow tract CVM susceptibility.

  15. Cortical Contribution to Linear, Non-linear and Frequency Components of Motor Variability Control during Standing.

    Science.gov (United States)

    König Ignasiak, Niklas; Habermacher, Lars; Taylor, William R; Singh, Navrag B

    2017-01-01

    Motor variability is an inherent feature of all human movements and reflects the quality of functional task performance. Depending on the requirements of the motor task, the human sensory-motor system is thought to be able to flexibly govern the appropriate level of variability. However, it remains unclear which neurophysiological structures are responsible for the control of motor variability. In this study, we tested the contribution of cortical cognitive resources on the control of motor variability (in this case postural sway) using a dual-task paradigm and furthermore observed potential changes in control strategy by evaluating Ia-afferent integration (H-reflex). Twenty healthy subjects were instructed to stand relaxed on a force plate with eyes open and closed, as well as while trying to minimize sway magnitude and performing a "subtracting-sevens" cognitive task. In total 25 linear and non-linear parameters were used to evaluate postural sway, which were combined using a Principal Components procedure. Neurophysiological response of Ia-afferent reflex loop was quantified using the Hoffman reflex. In order to assess the contribution of the H-reflex on the sway outcome in the different standing conditions multiple mixed-model ANCOVAs were performed. The results suggest that subjects were unable to further minimize their sway, despite actively focusing to do so. The dual-task had a destabilizing effect on PS, which could partly (by 4%) be counter-balanced by increasing reliance on Ia-afferent information. The effect of the dual-task was larger than the protective mechanism of increasing Ia-afferent information. We, therefore, conclude that cortical structures, as compared to peripheral reflex loops, play a dominant role in the control of motor variability.

  16. Three loop contributions to the matrix elements in the variable flavor number scheme

    Energy Technology Data Exchange (ETDEWEB)

    Bluemlein, Johannes; Hasselhuhn, Alexander [DESY (Germany); Schneider, Carsten [RISC, JKU Linz (Austria)

    2012-07-01

    The variable flavor number scheme may be used to describe parton distributions in the transition region in which one heavy quark gradually becomes a light flavor. We present first three-loop results to the massive operator matrix elements A{sub gg} and A{sub gq} for the contributions due to bubble topologies {proportional_to}T{sub F}{sup 2} n{sub f} at general values of the Mellin variable N. The calculation has been performed using higher transcendental functions and by applying modern summation technologies encoded in the package Sigma. These massive operator matrix elements describe the universal contributions in the matching of different flavor sectors, which are the logarithmic and constant contributions in the ratio of m{sup 2}{sub H}/Q{sup 2}, with Q{sup 2} the virtuality and m{sub H} the respective heavy quark mass. The framework allows to derive heavy quark parton distributions which are of relevance for calculating specific processes at hadron-hadron colliders.

  17. Variable Origin of the Superior Laryngeal Artery and Its Clinical Significance

    OpenAIRE

    Soubhagya R. Nayak1*, Ashwin Krishnamurthy2, Latha V. Prabhu2, Bhagath Kumar Potu3, Ishwar B. Bagoji4, Jiji PJ2 and Ganesh Kumar Chettiar2

    2011-01-01

    The superior laryngeal artery (SLA) is the dominant arterial supply of the laryngeal muscles, mucosa and glands. The purpose of the present study was to document the variable origin of the SLA in the carotid triangle. Although the variation in the SLA origin and morphology is important during the partial laryngectomy and reconstruction surgery of the larynx, the description of the SLA in modern literature is vague. The anatomy of SLA was studied in 37 adult South Indian preserved cadavers age...

  18. Variations of Histone Modification Patterns: Contributions of Inter-plant Variability and Technical Factors

    Directory of Open Access Journals (Sweden)

    Sylva Brabencová

    2017-12-01

    Full Text Available Inter-individual variability of conspecific plants is governed by differences in their genetically determined growth and development traits, environmental conditions, and adaptive responses under epigenetic control involving histone post-translational modifications. The apparent variability in histone modifications among plants might be increased by technical variation introduced in sample processing during epigenetic analyses. Thus, to detect true variations in epigenetic histone patterns associated with given factors, the basal variability among samples that is not associated with them must be estimated. To improve knowledge of relative contribution of biological and technical variation, mass spectrometry was used to examine histone modification patterns (acetylation and methylation among Arabidopsis thaliana plants of ecotypes Columbia 0 (Col-0 and Wassilewskija (Ws homogenized by two techniques (grinding in a cryomill or with a mortar and pestle. We found little difference in histone modification profiles between the ecotypes. However, in comparison of the biological and technical components of variability, we found consistently higher inter-individual variability in histone mark levels among Ws plants than among Col-0 plants (grown from seeds collected either from single plants or sets of plants. Thus, more replicates of Ws would be needed for rigorous analysis of epigenetic marks. Regarding technical variability, the cryomill introduced detectably more heterogeneity in the data than the mortar and pestle treatment, but mass spectrometric analyses had minor apparent effects. Our study shows that it is essential to consider inter-sample variance and estimate suitable numbers of biological replicates for statistical analysis for each studied organism when investigating changes in epigenetic histone profiles.

  19. Variations of Histone Modification Patterns: Contributions of Inter-plant Variability and Technical Factors.

    Science.gov (United States)

    Brabencová, Sylva; Ihnatová, Ivana; Potěšil, David; Fojtová, Miloslava; Fajkus, Jiří; Zdráhal, Zbyněk; Lochmanová, Gabriela

    2017-01-01

    Inter-individual variability of conspecific plants is governed by differences in their genetically determined growth and development traits, environmental conditions, and adaptive responses under epigenetic control involving histone post-translational modifications. The apparent variability in histone modifications among plants might be increased by technical variation introduced in sample processing during epigenetic analyses. Thus, to detect true variations in epigenetic histone patterns associated with given factors, the basal variability among samples that is not associated with them must be estimated. To improve knowledge of relative contribution of biological and technical variation, mass spectrometry was used to examine histone modification patterns (acetylation and methylation) among Arabidopsis thaliana plants of ecotypes Columbia 0 (Col-0) and Wassilewskija (Ws) homogenized by two techniques (grinding in a cryomill or with a mortar and pestle). We found little difference in histone modification profiles between the ecotypes. However, in comparison of the biological and technical components of variability, we found consistently higher inter-individual variability in histone mark levels among Ws plants than among Col-0 plants (grown from seeds collected either from single plants or sets of plants). Thus, more replicates of Ws would be needed for rigorous analysis of epigenetic marks. Regarding technical variability, the cryomill introduced detectably more heterogeneity in the data than the mortar and pestle treatment, but mass spectrometric analyses had minor apparent effects. Our study shows that it is essential to consider inter-sample variance and estimate suitable numbers of biological replicates for statistical analysis for each studied organism when investigating changes in epigenetic histone profiles.

  20. Nonalcoholic steatohepatitis in precision medicine: Unraveling the factors that contribute to individual variability.

    Science.gov (United States)

    Clarke, John D; Cherrington, Nathan J

    2015-07-01

    There are numerous factors in individual variability that make the development and implementation of precision medicine a challenge in the clinic. One of the main goals of precision medicine is to identify the correct dose for each individual in order to maximize therapeutic effect and minimize the occurrence of adverse drug reactions. Many promising advances have been made in identifying and understanding how factors such as genetic polymorphisms can influence drug pharmacokinetics (PK) and contribute to variable drug response (VDR), but it is clear that there remain many unidentified variables. Underlying liver diseases such as nonalcoholic steatohepatitis (NASH) alter absorption, distribution, metabolism, and excretion (ADME) processes and must be considered in the implementation of precision medicine. There is still a profound need for clinical investigation into how NASH-associated changes in ADME mediators, such as metabolism enzymes and transporters, affect the pharmacokinetics of individual drugs known to rely on these pathways for elimination. This review summarizes the key PK factors in individual variability and VDR and highlights NASH as an essential underlying factor that must be considered as the development of precision medicine advances. A multifactorial approach to precision medicine that considers the combination of two or more risk factors (e.g. genetics and NASH) will be required in our effort to provide a new era of benefit for patients. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. The Significance of the Spatial Variability of Rainfall on the Numerical Simulation of Urban Floods

    Directory of Open Access Journals (Sweden)

    Laurent Guillaume Courty

    2018-02-01

    Full Text Available The growth of urban population, combined with an increase of extreme events due to climate change call for a better understanding and representation of urban floods. The uncertainty in rainfall distribution is one of the most important factors that affects the watershed response to a given precipitation event. However, most of the investigations on this topic have considered theoretical scenarios, with little reference to case studies in the real world. This paper incorporates the use of spatially-variable precipitation data from a long-range radar in the simulation of the severe floods that impacted the city of Hull, U.K., in June 2007. This radar-based rainfall field is merged with rain gauge data using a Kriging with External Drift interpolation technique. The utility of this spatially-variable information is investigated through the comparison of computed flooded areas (uniform and radar against those registered by public authorities. Both results show similar skills at reproducing the real event, but differences in the total precipitated volumes, water depths and flooded areas are illustrated. It is envisaged that in urban areas and with the advent of higher resolution radars, these differences will be more important and call for further investigation.

  2. Factors contributing to radiocaesium variability in upland sheep flocks in west Cumbria (United Kingdom)

    International Nuclear Information System (INIS)

    Beresford, N.A.; Barnett, C.L.; Wright, S.M.; Howard, B.J.; Crout, N.M.J.

    2007-01-01

    Following the Chernobyl accident in 1986, restrictions were placed on the movement and slaughter of sheep within upland areas of the UK because radiocaesium activity concentrations in their meat exceeded 1000 Bq kg -1 fresh weight. Some farms remain under restriction in 2007. From 1991 to 1993 detailed studies were conducted on three sheep farms within the restricted area of west Cumbria to systematically assess the various parameters which may contribute to the observed variability in radiocaesium activity concentrations within sheep flocks. This paper reports the spatial variation in soil and vegetation activity concentrations across the grazed areas at these farms and determines the influence of grazing behaviour on variability in 137 Cs activity concentrations between individual sheep within the flocks. Together with previously reported results, these new data are used to draw conclusions on the factors determining variability within the three flocks. However, the factors are too site specific to be able to generalise the findings to other farms within the restricted areas of the UK

  3. Tropical Atlantic Contributions to Strong Rainfall Variability Along the Northeast Brazilian Coast

    Directory of Open Access Journals (Sweden)

    G. A. Hounsou-gbo

    2015-01-01

    Full Text Available Tropical Atlantic (TA Ocean-atmosphere interactions and their contributions to strong variability of rainfall along the Northeast Brazilian (NEB coast were investigated for the years 1974–2008. The core rainy seasons of March-April and June-July were identified for Fortaleza (northern NEB; NNEB and Recife (eastern NEB; ENEB, respectively. Lagged linear regressions between sea surface temperature (SST and pseudo wind stress (PWS anomalies over the entire TA and strong rainfall anomalies at Fortaleza and Recife show that the rainfall variability of these regions is differentially influenced by the dynamics of the TA. When the Intertropical Convergence Zone is abnormally displaced southward a few months prior to the NNEB rainy season, the associated meridional mode increases humidity and precipitation during the rainy season. Additionally, this study shows predictive effect of SST, meridional PWS, and barrier layer thickness, in the Northwestern equatorial Atlantic, on the NNEB rainfall. The dynamical influence of the TA on the June-July ENEB rainfall variability shows a northwestward-propagating area of strong, positively correlated SST from the southeastern TA to the southwestern Atlantic warm pool (SAWP offshore of Brazil. Our results also show predictive effect of SST, zonal PWS, and mixed layer depth, in the SAWP, on the ENEB rainfall.

  4. On the selection of significant variables in a model for the deteriorating process of facades

    Science.gov (United States)

    Serrat, C.; Gibert, V.; Casas, J. R.; Rapinski, J.

    2017-10-01

    In previous works the authors of this paper have introduced a predictive system that uses survival analysis techniques for the study of time-to-failure in the facades of a building stock. The approach is population based, in order to obtain information on the evolution of the stock across time, and to help the manager in the decision making process on global maintenance strategies. For the decision making it is crutial to determine those covariates -like materials, morphology and characteristics of the facade, orientation or environmental conditions- that play a significative role in the progression of different failures. The proposed platform also incorporates an open source GIS plugin that includes survival and test moduli that allow the investigator to model the time until a lesion taking into account the variables collected during the inspection process. The aim of this paper is double: a) to shortly introduce the predictive system, as well as the inspection and the analysis methodologies and b) to introduce and illustrate the modeling strategy for the deteriorating process of an urban front. The illustration will be focused on the city of L’Hospitalet de Llobregat (Barcelona, Spain) in which more than 14,000 facades have been inspected and analyzed.

  5. Variability in source sediment contributions by applying different statistic test for a Pyrenean catchment.

    Science.gov (United States)

    Palazón, L; Navas, A

    2017-06-01

    Information on sediment contribution and transport dynamics from the contributing catchments is needed to develop management plans to tackle environmental problems related with effects of fine sediment as reservoir siltation. In this respect, the fingerprinting technique is an indirect technique known to be valuable and effective for sediment source identification in river catchments. Large variability in sediment delivery was found in previous studies in the Barasona catchment (1509 km 2 , Central Spanish Pyrenees). Simulation results with SWAT and fingerprinting approaches identified badlands and agricultural uses as the main contributors to sediment supply in the reservoir. In this study the Kruskal-Wallis H-test and (3) principal components analysis. Source contribution results were different between assessed options with the greatest differences observed for option using #3, including the two step process: principal components analysis and discriminant function analysis. The characteristics of the solutions by the applied mixing model and the conceptual understanding of the catchment showed that the most reliable solution was achieved using #2, the two step process of Kruskal-Wallis H-test and discriminant function analysis. The assessment showed the importance of the statistical procedure used to define the optimum composite fingerprint for sediment fingerprinting applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. The contribution of human agricultural activities to increasing evapotranspiration is significantly greater than climate change effect over Heihe agricultural region.

    Science.gov (United States)

    Zou, Minzhong; Niu, Jun; Kang, Shaozhong; Li, Xiaolin; Lu, Hongna

    2017-08-18

    Evapotranspiration (ET) is a major component linking the water, energy, and carbon cycles. Understanding changes in ET and the relative contribution rates of human activity and of climate change at the basin scale is important for sound water resources management. In this study, changes in ET in the Heihe agricultural region in northwest China during 1984-2014 were examined using remotely-sensed ET data with the Soil and Water Assessment Tool (SWAT). Correlation analysis identified the dominant factors that influence change in ET per unit area and those that influence change in total ET. Factor analysis identified the relative contribution rates of the dominant factors in each case. The results show that human activity, which includes factors for agronomy and irrigation, and climate change, including factors for precipitation and relative humidity, both contribute to increases in ET per unit area at rates of 60.93% and 28.01%, respectively. Human activity, including the same factors, and climate change, including factors for relative humidity and wind speed, contribute to increases in total ET at rates of 53.86% and 35.68%, respectively. Overall, in the Heihe agricultural region, the contribution of human agricultural activities to increased ET was significantly greater than that of climate change.

  7. Significant and variable linear polarization during the prompt optical flash of GRB 160625B.

    Science.gov (United States)

    Troja, E.; Lipunov, V. M.; Mundell, C. G.; Butler, N. R.; Watson, A. M.; Kobayashi, S.; Cenko, S. B.; Marshall, F. E.; Ricci, R.; Fruchter, A.; Wieringa, M. H.; Gorbovskoy, E. S.; Kornilov, V.; Kutyrev, A.; Lee, W. H.; Toy, V.; Tyurina, N. V.; Budnev, N. M.; Buckley, D. A. H.; González, J.; Gress, O.; Horesh, A.; Panasyuk, M. I.; Prochaska, J. X.; Ramirez-Ruiz, E.; Rebolo Lopez, R.; Richer, M. G.; Roman-Zuniga, C.; Serra-Ricart, M.; Yurkov, V.; Gehrels, N.

    2017-07-01

    Newly formed black holes of stellar mass launch collimated outflows (jets) of ionized matter that approach the speed of light. These outflows power prompt, brief and intense flashes of γ-rays known as γ-ray bursts (GRBs), followed by longer-lived afterglow radiation that is detected across the electromagnetic spectrum. Measuring the polarization of the observed GRB radiation provides a direct probe of the magnetic fields in the collimated jets. Rapid-response polarimetric observations of newly discovered bursts have probed the initial afterglow phase, and show that, minutes after the prompt emission has ended, the degree of linear polarization can be as high as 30 per cent - consistent with the idea that a stable, globally ordered magnetic field permeates the jet at large distances from the central source. By contrast, optical and γ-ray observations during the prompt phase have led to discordant and often controversial results, and no definitive conclusions have been reached regarding the origin of the prompt radiation or the configuration of the magnetic field. Here we report the detection of substantial (8.3 ± 0.8 per cent from our most conservative simulation), variable linear polarization of a prompt optical flash that accompanied the extremely energetic and long-lived prompt γ-ray emission from GRB 160625B. Our measurements probe the structure of the magnetic field at an early stage of the jet, closer to its central black hole, and show that the prompt phase is produced via fast-cooling synchrotron radiation in a large-scale magnetic field that is advected from the black hole and distorted by dissipation processes within the jet.

  8. Variability of Cenococcum colonization and its ecophysiological significance for young conifers at alpine-treeline.

    Science.gov (United States)

    Hasselquist, Niles; Germino, Matthew J; McGonigle, Terence; Smith, William K

    2005-03-01

    * Plants establishing in environments that are marginal for growth could be particularly sensitive to mycorrhizal associations. We investigated ectomycorrhizal colonization and its significance for young conifers growing at, or above, their normal limits for growth, in the alpine-treeline ecotone. * Colonization of seedlings (treeline may include a below-ground, mycorrhizal component that complements previously reported effects of trees on the microclimate and ecophysiology of seedlings.

  9. Practical way to avoid spurious geometrical contributions in Brillouin light scattering experiments at variable scattering angles.

    Science.gov (United States)

    Battistoni, Andrea; Bencivenga, Filippo; Fioretto, Daniele; Masciovecchio, Claudio

    2014-10-15

    In this Letter, we present a simple method to avoid the well-known spurious contributions in the Brillouin light scattering (BLS) spectrum arising from the finite aperture of collection optics. The method relies on the use of special spatial filters able to select the scattered light with arbitrary precision around a given value of the momentum transfer (Q). We demonstrate the effectiveness of such filters by analyzing the BLS spectra of a reference sample as a function of scattering angle. This practical and inexpensive method could be an extremely useful tool to fully exploit the potentiality of Brillouin acoustic spectroscopy, as it will easily allow for effective Q-variable experiments with unparalleled luminosity and resolution.

  10. Sulfur isotope variability of oceanic DMSP generation and its contributions to marine biogenic sulfur emissions.

    Science.gov (United States)

    Oduro, Harry; Van Alstyne, Kathryn L; Farquhar, James

    2012-06-05

    Oceanic dimethylsulfoniopropionate (DMSP) is the precursor to dimethylsulfide (DMS), which plays a role in climate regulation through transformation to methanesulfonic acid (MSA) and non-seasalt sulfate (NSS-SO(4)(2-)) aerosols. Here, we report measurements of the abundance and sulfur isotope compositions of DMSP from one phytoplankton species (Prorocentrum minimum) and five intertidal macroalgal species (Ulva lactuca, Ulva linza, Ulvaria obscura, Ulva prolifera, and Polysiphonia hendryi) in marine waters. We show that the sulfur isotope compositions (δ(34)S) of DMSP are depleted in (34)S relative to the source seawater sulfate by ∼1-3‰ and are correlated with the observed intracellular content of methionine, suggesting a link to metabolic pathways of methionine production. We suggest that this variability of δ(34)S is transferred to atmospheric geochemical products of DMSP degradation (DMS, MSA, and NSS-SO(4)(2-)), carrying implications for the interpretation of variability in δ(34)S of MSA and NSS-SO(4)(2-) that links them to changes in growth conditions and populations of DMSP producers rather than to the contributions of DMS and non-DMS sources.

  11. Contribution of competition for light to within-species variability in stomatal conductance

    Science.gov (United States)

    Loranty, Michael M.; Mackay, D. Scott; Ewers, Brent E.; Traver, Elizabeth; Kruger, Eric L.

    2010-05-01

    Sap flux (JS) measurements were collected across two stands dominated by either trembling aspen or sugar maple in northern Wisconsin. Observed canopy transpiration (EC-obs) values derived from JS were used to parameterize the Terrestrial Regional Ecosystem Exchange Simulator ecosystem model. Modeled values of stomatal conductance (GS) were used to determine reference stomatal conductance (GSref), a proxy for GS that removes the effects of temporal responses to vapor pressure deficit (D) on spatial patterns of GS. Values of GSref were compared to observations of soil moisture, several physiological variables, and a competition index (CI) derived from a stand inventory, to determine the underlying cause of observed variability. Considerable variability in GSref between individual trees was found, with values ranging from 20 to 200 mmol m-2 s-1 and 20 to 100 mmol m-2 s-1 at the aspen and maple stands, respectively. Model-derived values of GSref and a sensitivity to D parameter (m) showed good agreement with a known empirical relationship for both stands. At both sites, GSref did not vary with topographic position, as indicated by surface soil moisture. No relationships were observed between GSref and tree height (HT), and a weak correlation with sapwood area (AS) was only significant for aspen. Significant nonlinear inverse relationships between GSref and CI were observed at both stands. Simulations with uniform reductions in incident photosynthetically active radiation (Q0) resulted in better agreement between observed and simulated EC. Our results suggest a link between photosynthesis and plant hydraulics whereby individual trees subject to photosynthetic limitation as a result of competitive shading exhibit a dynamic stomatal response resulting in a more conservative strategy for managing hydrologic resources.

  12. Homeostatic and circadian contribution to EEG and molecular state variables of sleep regulation.

    Science.gov (United States)

    Curie, Thomas; Mongrain, Valérie; Dorsaz, Stéphane; Mang, Géraldine M; Emmenegger, Yann; Franken, Paul

    2013-03-01

    Besides their well-established role in circadian rhythms, our findings that the forebrain expression of the clock-genes Per2 and Dbp increases and decreases, respectively, in relation to time spent awake suggest they also play a role in the homeostatic aspect of sleep regulation. Here, we determined whether time of day modulates the effects of elevated sleep pressure on clock-gene expression. Time of day effects were assessed also for recognized electrophysiological (EEG delta power) and molecular (Homer1a) markers of sleep homeostasis. EEG and qPCR data were obtained for baseline and recovery from 6-h sleep deprivation starting at ZT0, -6, -12, or -18. Mouse sleep laboratory. Male mice. Sleep deprivation. The sleep-deprivation induced changes in Per2 and Dbp expression importantly varied with time of day, such that Per2 could even decrease during sleep deprivations occurring at the decreasing phase in baseline. Dbp showed similar, albeit opposite dynamics. These unexpected results could be reliably predicted assuming that these transcripts behave according to a driven damped harmonic oscillator. As expected, the sleep-wake distribution accounted for a large degree of the changes in EEG delta power and Homer1a. Nevertheless, the sleep deprivation-induced increase in delta power varied also with time of day with higher than expected levels when recovery sleep started at dark onset. Per2 and delta power are widely used as exclusive state variables of the circadian and homeostatic process, respectively. Our findings demonstrate a considerable cross-talk between these two processes. As Per2 in the brain responds to both sleep loss and time of day, this molecule is well positioned to keep track of and to anticipate homeostatic sleep need. Curie T; Mongrain V; Dorsaz S; Mang GM; Emmenegger Y; Franken P. Homeostatic and circadian contribution to EEG and molecular state variables of sleep regulation. SLEEP 2013;36(3):311-323.

  13. Selective excretion of IgA in rat bronchial secretions: lack of significant contribution from plasma IgA

    International Nuclear Information System (INIS)

    Lemaitre-Coelho, I.; Yamakido, M.; Montgomery, P.C.; Langendries, A.E.; Vaerman, J.P.

    1982-01-01

    Concentrated rat bronchial washings (BW) were analyzed by gel-filtration and immunochemical methods. BW contained mainly albumin, transferrin and IgG. Free secretory component and secretory IgA were identified in BW; the BW-IgA had the same three sedimentation coefficients, i.e. +/- 11 S, 13 S, 15 S by sucrose density gradient ultracentrifugation, as rat milk and rat bile IgA; the three peaks were secretory IgA. Compared to serum, and relatively to albumin, BW were significantly enriched in IgA, although much less than rat bile. Purified polyclonal rat polymeric 125 I-IgA was injected intravenously into normal rats, and into rats with bile duct ligation or partial hepatectomy, which decrease the liver plasma-to-bile transfer of IgA. BW were then collected, one or four hours later, to assess the recovery of the 125 I-IgA in BW and to estimate the contribution of serum IgA to BW-IgA. Very little 125 I-IgA (less than 0.2%) was recovered in all BW. The specific activity, measured only in the rat with the highest recovery in BW, was 20 times lower in BW than in serum. The data demonstrate that rat serum IgA does not contribute significantly to IgA in BW

  14. Significant contribution of stacking faults to the strain hardening behavior of Cu-15%Al alloy with different grain sizes.

    Science.gov (United States)

    Tian, Y Z; Zhao, L J; Chen, S; Shibata, A; Zhang, Z F; Tsuji, N

    2015-11-19

    It is commonly accepted that twinning can induce an increase of strain-hardening rate during the tensile process of face-centered cubic (FCC) metals and alloys with low stacking fault energy (SFE). In this study, we explored the grain size effect on the strain-hardening behavior of a Cu-15 at.%Al alloy with low SFE. Instead of twinning, we detected a significant contribution of stacking faults (SFs) irrespective of the grain size even in the initial stage of tensile process. In contrast, twinning was more sensitive to the grain size, and the onset of deformation twins might be postponed to a higher strain with increasing the grain size. In the Cu-15 at.%Al alloy with a mean grain size of 47 μm, there was a stage where the strain-hardening rate increases with strain, and this was mainly induced by the SFs instead of twinning. Thus in parallel with the TWIP effect, we proposed that SFs also contribute significantly to the plasticity of FCC alloys with low SFE.

  15. Local Versus Remote Contributions of Soil Moisture to Near-Surface Temperature Variability

    Science.gov (United States)

    Koster, R.; Schubert, S.; Wang, H.; Chang, Y.

    2018-01-01

    Soil moisture variations have a straightforward impact on overlying air temperatures, wetter soils can induce higher evaporative cooling of the soil and thus, locally, cooler temperatures overall. Not known, however, is the degree to which soil moisture variations can affect remote air temperatures through their impact on the atmospheric circulation. In this talk we describe a two-pronged analysis that addresses this question. In the first segment, an extensive ensemble of NASA/GSFC GEOS-5 atmospheric model simulations is analyzed statistically to isolate and quantify the contributions of various soil moisture states, both local and remote, to the variability of air temperature at a given local site. In the second segment, the relevance of the derived statistical relationships is evaluated by applying them to observations-based data. Results from the second segment suggest that the GEOS-5-based relationships do, at least to first order, hold in nature and thus may provide some skill to forecasts of air temperature at subseasonal time scales, at least in certain regions.

  16. Correction of the significance level when attempting multiple transformations of an explanatory variable in generalized linear models

    Science.gov (United States)

    2013-01-01

    Background In statistical modeling, finding the most favorable coding for an exploratory quantitative variable involves many tests. This process involves multiple testing problems and requires the correction of the significance level. Methods For each coding, a test on the nullity of the coefficient associated with the new coded variable is computed. The selected coding corresponds to that associated with the largest statistical test (or equivalently the smallest pvalue). In the context of the Generalized Linear Model, Liquet and Commenges (Stat Probability Lett,71:33–38,2005) proposed an asymptotic correction of the significance level. This procedure, based on the score test, has been developed for dichotomous and Box-Cox transformations. In this paper, we suggest the use of resampling methods to estimate the significance level for categorical transformations with more than two levels and, by definition those that involve more than one parameter in the model. The categorical transformation is a more flexible way to explore the unknown shape of the effect between an explanatory and a dependent variable. Results The simulations we ran in this study showed good performances of the proposed methods. These methods were illustrated using the data from a study of the relationship between cholesterol and dementia. Conclusion The algorithms were implemented using R, and the associated CPMCGLM R package is available on the CRAN. PMID:23758852

  17. The cosmopolitan maternal heritage of the Thoroughbred racehorse breed shows a significant contribution from British and Irish native mares.

    Science.gov (United States)

    Bower, M A; Campana, M G; Whitten, M; Edwards, C J; Jones, H; Barrett, E; Cassidy, R; Nisbet, R E R; Hill, E W; Howe, C J; Binns, M

    2011-04-23

    The paternal origins of Thoroughbred racehorses trace back to a handful of Middle Eastern stallions, imported to the British Isles during the seventeenth century. Yet, few details of the foundation mares were recorded, in many cases not even their names (several different maternal lineages trace back to 'A Royal Mare'). This has fuelled intense speculation over their origins. We examined mitochondrial DNA from 1929 horses to determine the origin of Thoroughbred foundation mares. There is no evidence to support exclusive Arab maternal origins as some historical records have suggested, or a significant importation of Oriental mares (the term used in historic records to refer to Middle East and western Asian breeds including Arab, Akhal-Teke, Barb and Caspian). Instead, we show that Thoroughbred foundation mares had a cosmopolitan European heritage with a far greater contribution from British and Irish Native mares than previously recognized.

  18. The cosmopolitan maternal heritage of the Thoroughbred racehorse breed shows a significant contribution from British and Irish native mares

    Science.gov (United States)

    Bower, M. A.; Campana, M. G.; Whitten, M.; Edwards, C. J.; Jones, H.; Barrett, E.; Cassidy, R.; Nisbet, R. E. R.; Hill, E. W.; Howe, C. J.; Binns, M.

    2011-01-01

    The paternal origins of Thoroughbred racehorses trace back to a handful of Middle Eastern stallions, imported to the British Isles during the seventeenth century. Yet, few details of the foundation mares were recorded, in many cases not even their names (several different maternal lineages trace back to ‘A Royal Mare’). This has fuelled intense speculation over their origins. We examined mitochondrial DNA from 1929 horses to determine the origin of Thoroughbred foundation mares. There is no evidence to support exclusive Arab maternal origins as some historical records have suggested, or a significant importation of Oriental mares (the term used in historic records to refer to Middle East and western Asian breeds including Arab, Akhal-Teke, Barb and Caspian). Instead, we show that Thoroughbred foundation mares had a cosmopolitan European heritage with a far greater contribution from British and Irish Native mares than previously recognized. PMID:20926431

  19. Smoking cessation programmes in radon affected areas: can they make a significant contribution to reducing radon-induced lung cancers?

    International Nuclear Information System (INIS)

    Denman, A.R.; Groves-Kirkby, C.J.; Timson, K.; Shield, G.; Rogers, S.; Phillips, P.S.

    2008-01-01

    Domestic radon levels in parts of the UK are sufficiently high to increase the risk of lung cancer in the occupants. Public health campaigns in Northamptonshire, a designated radon affected area with 6.3% of homes having average radon levels over the UK action level of 200 Bq m -3 , have encouraged householders to test for radon and then to carry out remediation in their homes, but have been only partially successful. Only 40% of Northamptonshire houses have been tested, and only 15% of householders finding raised levels proceed to remediate. Of those who did remediate, only 9% smoked, compared to a countywide average of 28.8%. This is unfortunate, since radon and smoking combine to place the individual at higher risk by a factor of around 4, and suggests that current strategies to reduce domestic radon exposure are not reaching those most at risk. During 2004-5, the NHS Stop Smoking Services in Northamptonshire assisted 2,808 smokers to quit to the 4-week stage, with some 30% of 4-week quitters remaining quitters at 1 year. We consider whether smoking cessation campaigns make significant contributions to radon risk reduction on their own, by assessing individual occupants' risk of developing lung cancer from knowledge of their age, gender, and smoking habits, together with he radon level in their house. The results demonstrate that smoking cessation programmes have significant added value in radon affected areas, and contribute a greater health benefit than reducing radon levels in the smokers' homes, whilst they remain smokers. Additionally, results are presented from a questionnaire-based survey of quitters, addressing their reasons for seeking help in quitting smoking, and whether knowledge of radon risks influenced this decision. The impact of these findings on future public health campaigns to reduce the impact of radon and smoking are discussed. (author)

  20. Genetic variability, correlation and path analysis of yield contributing characters in sweet potato (ipomoea batatas lam.)

    International Nuclear Information System (INIS)

    Hossain, M.D.; Rabbani, M.G.; Mollah, M.L.R.

    2000-01-01

    Evaluation of 30 sweet potato (Ipomoea batatas Lam.) genotypes for yield contributing characters and tuber yield per plant revealed high phenotypic and genotypic coefficient of variation (PCV and GCV, respectively) for number of tubers per plant, average tuber weight and tuber yield per plant. The heritability and genetic advance were higher for tuber yield per plant, average tuber weight and number of tubers per plant. These three characters also reflected high heritability as well as high genetic advance. As high positive significant correlation, as well as positive direct effect of average tuber weight and number of tubers per plant on tuber yield per plant were found, these characters should be given prime importance for selecting high yielding sweet potato genotypes. (author)

  1. Homeostatic and Circadian Contribution to EEG and Molecular State Variables of Sleep Regulation

    Science.gov (United States)

    Curie, Thomas; Mongrain, Valérie; Dorsaz, Stéphane; Mang, Géraldine M.; Emmenegger, Yann; Franken, Paul

    2013-01-01

    Study Objectives: Besides their well-established role in circadian rhythms, our findings that the forebrain expression of the clock-genes Per2 and Dbp increases and decreases, respectively, in relation to time spent awake suggest they also play a role in the homeostatic aspect of sleep regulation. Here, we determined whether time of day modulates the effects of elevated sleep pressure on clock-gene expression. Time of day effects were assessed also for recognized electrophysiological (EEG delta power) and molecular (Homer1a) markers of sleep homeostasis. Design: EEG and qPCR data were obtained for baseline and recovery from 6-h sleep deprivation starting at ZT0, -6, -12, or -18. Setting: Mouse sleep laboratory. Participants: Male mice. Interventions: Sleep deprivation. Results: The sleep-deprivation induced changes in Per2 and Dbp expression importantly varied with time of day, such that Per2 could even decrease during sleep deprivations occurring at the decreasing phase in baseline. Dbp showed similar, albeit opposite dynamics. These unexpected results could be reliably predicted assuming that these transcripts behave according to a driven damped harmonic oscillator. As expected, the sleep-wake distribution accounted for a large degree of the changes in EEG delta power and Homer1a. Nevertheless, the sleep deprivation-induced increase in delta power varied also with time of day with higher than expected levels when recovery sleep started at dark onset. Conclusions: Per2 and delta power are widely used as exclusive state variables of the circadian and homeostatic process, respectively. Our findings demonstrate a considerable cross-talk between these two processes. As Per2 in the brain responds to both sleep loss and time of day, this molecule is well positioned to keep track of and to anticipate homeostatic sleep need. Citation: Curie T; Mongrain V; Dorsaz S; Mang GM; Emmenegger Y; Franken P. Homeostatic and circadian contribution to EEG and molecular state

  2. HMGB1 and Extracellular Histones Significantly Contribute to Systemic Inflammation and Multiple Organ Failure in Acute Liver Failure.

    Science.gov (United States)

    Yang, Runkuan; Zou, Xiaoping; Tenhunen, Jyrki; Tønnessen, Tor Inge

    2017-01-01

    Acute liver failure (ALF) is the culmination of severe liver cell injury from a variety of causes. ALF occurs when the extent of hepatocyte death exceeds the hepatic regenerative capacity. ALF has a high mortality that is associated with multiple organ failure (MOF) and sepsis; however, the underlying mechanisms are still not clear. Emerging evidence shows that ALF patients/animals have high concentrations of circulating HMGB1, which can contribute to multiple organ injuries and mediate gut bacterial translocation (BT). BT triggers/induces systemic inflammatory responses syndrome (SIRS), which can lead to MOF in ALF. Blockade of HMGB1 significantly decreases BT and improves hepatocyte regeneration in experimental acute fatal liver injury. Therefore, HMGB1 seems to be an important factor that links BT and systemic inflammation in ALF. ALF patients/animals also have high levels of circulating histones, which might be the major mediators of systemic inflammation in patients with ALF. Extracellular histones kill endothelial cells and elicit immunostimulatory effect to induce multiple organ injuries. Neutralization of histones can attenuate acute liver, lung, and brain injuries. In conclusion, HMGB1 and histones play a significant role in inducing systemic inflammation and MOF in ALF.

  3. HMGB1 and Extracellular Histones Significantly Contribute to Systemic Inflammation and Multiple Organ Failure in Acute Liver Failure

    Directory of Open Access Journals (Sweden)

    Runkuan Yang

    2017-01-01

    Full Text Available Acute liver failure (ALF is the culmination of severe liver cell injury from a variety of causes. ALF occurs when the extent of hepatocyte death exceeds the hepatic regenerative capacity. ALF has a high mortality that is associated with multiple organ failure (MOF and sepsis; however, the underlying mechanisms are still not clear. Emerging evidence shows that ALF patients/animals have high concentrations of circulating HMGB1, which can contribute to multiple organ injuries and mediate gut bacterial translocation (BT. BT triggers/induces systemic inflammatory responses syndrome (SIRS, which can lead to MOF in ALF. Blockade of HMGB1 significantly decreases BT and improves hepatocyte regeneration in experimental acute fatal liver injury. Therefore, HMGB1 seems to be an important factor that links BT and systemic inflammation in ALF. ALF patients/animals also have high levels of circulating histones, which might be the major mediators of systemic inflammation in patients with ALF. Extracellular histones kill endothelial cells and elicit immunostimulatory effect to induce multiple organ injuries. Neutralization of histones can attenuate acute liver, lung, and brain injuries. In conclusion, HMGB1 and histones play a significant role in inducing systemic inflammation and MOF in ALF.

  4. The varied contribution of significant others to Complementary and Alternative Medicine (CAM) uptake by men with cancer: a qualitative analysis.

    Science.gov (United States)

    Klafke, Nadja; Eliott, Jaklin A; Olver, Ian N; Wittert, Gary A

    2014-06-01

    To explore how men's Significant Others (SOs), including family members and close friends, contribute to the uptake and maintenance of specific CAM therapies. This study was the second, qualitative phase of a mixed-methods project investigating the use of CAM in an Australian male cancer population. Male participants were purposefully selected from a pool of 403 patients who answered a survey in the first quantitative phase (94% response rate and 86% consent rate for follow-up interview). Then semi-structured interviews among 26 men with a variety of cancers and 24 SOs were conducted. All 43 interviews were recorded, transcribed, and analysed thematically. Men used CAM/Natural products to cope with physical concerns, and this was actively supported by men's SOs who contributed to the uptake and maintenance of these CAMs. The shared CAM preparation and consumption functioned to strengthen the bond between men and their SOs, and also helped men's SOs to cope with uncertainty and regain control. In contrast, men practiced CAM/Mind-body medicine to receive emotional benefits, and only rarely shared this practice with their SOs, indicating a need for coping with emotions in a private way. Men's CAM use is a multifaceted process that can be better understood by considering CAM categories separately. CAM/Natural products help men to cope with physical concerns, while CAM/Mind-body medicine assist men to cope with their emotions in a private way. Oncology professionals can use this information to better promote and implement integrative cancer care services. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. The contribution of hydroxylamine content to spatial variability of N2O formation in soil of a Norway spruce forest

    Science.gov (United States)

    Liu, Shurong; Herbst, Michael; Bol, Roland; Gottselig, Nina; Pütz, Thomas; Weymann, Daniel; Wiekenkamp, Inge; Vereecken, Harry; Brüggemann, Nicolas

    2016-04-01

    Hydroxylamine (NH2OH), a reactive intermediate of several microbial nitrogen turnover processes, is a potential precursor of nitrous oxide (N2O) formation in the soil. However, the contribution of soil NH2OH to soil N2O emission rates in natural ecosystems is unclear. Here, we determined the spatial variability of NH2OH content and potential N2O emission rates of organic (Oh) and mineral (Ah) soil layers of a Norway spruce forest, using a recently developed analytical method for the determination of soil NH2OH content, combined with a geostatistical Kriging approach. Potential soil N2O emission rates were determined by laboratory incubations under oxic conditions, followed by gas chromatographic analysis and complemented by ancillary measurements of soil characteristics. Stepwise multiple regressions demonstrated that the potential N2O emission rates, NH2OH and nitrate (NO3-) content were spatially highly correlated, with hotspots for all three parameters observed in the headwater of a small creek flowing through the sampling area. In contrast, soil ammonium (NH4+) was only weakly correlated with potential N2O emission rates, and was excluded from the multiple regression models. While soil NH2OH content explained the potential soil N2O emission rates best for both layers, also NO3- and Mn content turned out to be significant parameters explaining N2O formation in both soil layers. The Kriging approach was improved markedly by the addition of the co-variable information of soil NH2OH and NO3- content. The results indicate that determination of soil NH2OH content could provide crucial information for the prediction of the spatial variability of soil N2O emissions.

  6. Climatic fluctuations as a significant contributing factor for volcanic collapses. Evidence from Mexico during the Late Pleistocene

    Science.gov (United States)

    Capra, L.; Bernal-Uruchurtu, J. P.; Carrasco, G.

    2013-05-01

    Climate oscillations have significantly contributed to the planet's evolution, including volcanic activity. Major glaciations have been considered not only as a triggering mechanism for large magmatic eruptions but also inducing volcano instability. Generally, volcano instability can be inferred from detailed volcanological and structural studies of a volcano and its associated depositional sequence, but the triggering mechanism has been always difficult to infer. In this paper, we present evidence of how climatic variations during the Late Pleistocene could have forced sector collapses of the main Mexican stratovolcanoes and enhanced the mobility of associated massive flows inducing the transformation of debris avalanche into debris flows. In particular, the climatic record based on atmospheric moisture content from robustly dated lake record from Guatemala and a U/Th dated speleothem from New Mexico are used here as indicators of summer and winter precipitation. Depositional sequences associated with Late Pleistocene sector collapses of Volcan de Colima, Nevado de Toluca, Citlaltepetl (Pico de Orizaba) and Cofre de Perote volcanoes are here analyzed. Comparing the timing of the event with the climatic record, a combination of summer and/or winter pluvial conditions could have forced and triggered the failure of already unstable volcanoes, even during glacier advances (as for the Citlaltepetl event). Independently of the main cause of the volcano instability (magmatic or tectonic) it is important to highlight that the climatic factor played an important role in enhancing the volcano instability and promoted the lateral transformation of debris avalanches, which under dry conditions would have affected more limited areas.

  7. Can Ambulatory Blood Pressure Variability Contribute to Individual Cardiovascular Risk Stratification?

    Directory of Open Access Journals (Sweden)

    Annamária Magdás

    2016-01-01

    Full Text Available Objective. The aim of this study is to define the normal range for average real variability (ARV and to establish whether it can be considered as an additional cardiovascular risk factor. Methods. In this observational study, 110 treated hypertensive patients were included and admitted for antihypertensive treatment adjustment. Circadian blood pressure was recorded with validated devices. Blood pressure variability (BPV was assessed according to the ARV definition. Based on their variability, patients were classified into low, medium, and high variability groups using the fuzzy c-means algorithm. To assess cardiovascular risk, blood samples were collected. Characteristics of the groups were compared by ANOVA tests. Results. Low variability was defined as ARV below 9.8 mmHg (32 patients, medium as 9.8–12.8 mmHg (48 patients, and high variability above 12.8 mmHg (30 patients. Mean systolic blood pressure was 131.2 ± 16.7, 135.0 ± 12.1, and 141.5 ± 11.4 mmHg in the low, medium, and high variability groups, respectively (p=0.0113. Glomerular filtration rate was 78.6 ± 29.3, 74.8 ± 26.4, and 62.7±23.2 mL/min/1.73 m2 in the low, medium, and high variability groups, respectively (p=0.0261. Conclusion. Increased values of average real variability represent an additional cardiovascular risk factor. Therefore, reducing BP variability might be as important as achieving optimal BP levels, but there is need for further studies to define a widely acceptable threshold value.

  8. The clinical significance of detection to heart rate deceleration capacity and heart rate variability in patients with chronic heart failure

    Directory of Open Access Journals (Sweden)

    Jiang-rong Zhou

    2015-01-01

    Full Text Available Objective: To study the change of heart rate deceleration capacity ( DC and heart rate variability in patients with chronic heart failure (CHF and its relationship with left ventricular ejection fraction (LVEF. Methods: DC, LVEF, time and frequency domain parameters of HRV were measured in 66 patients with CHF and 34 healthy adults (control group by using 24h Holter recordings and Echocardiography. The standard deviation of normal R-R intervals( SDNN, squares of differences between adjacent NN intervals ( RMSSD,low frequency power( LFn and high frequency power( HFn and the changes of LVEF were compared between  the two groups,the relationship between DC,LVEF and HRV were studied in patients with CHF. Results: The median value of DC in the patients with CHF was significantly lower than that in control group( 3.1 ± 2.4 ms vs 7.2 ± 1.3 ms,P <0.01.Incidence of abnormal DC in the CHF group was 57.5%,which was significantly higher than that in the control group (P <0.01.The HRV index, including SDNN、RMSSD、LFn、HFn, in the CHF group was significantly lower than that in normal control group (P < 0.01. Significant positive correlation between HRV index and LVEF were confirmed (P < 0.01. Conclusions: DC and HRV index are lower in patients with CHF and have a good correlation with the left ventricular ejection fraction.

  9. Outline of an Anthropological Contribution to the Study of Snake Venom Variability: The Case of Echis sp. Envenomation

    Directory of Open Access Journals (Sweden)

    Tilman Musch

    2014-03-01

    Full Text Available An understanding of the variability of snake venom composition is of high relevance for adequate treatment of snakebites. Clinical observations of bite victims are considered as a first step in the study of venom variability. The present paper suggests the study of local clinical observations made by healers as an anthropological contribution to the interdisci-plinary research of venom variability on a species and subspecies level. Such an anthropological contribution will take into account cultural particularities of a region. In order to illustrate his approach, the author describes his ethnozoological and ethnomedical fieldwork among Zarma and Tuareg in western Niger where he studied envenomation by Echis leucogaster. This species is of particular interest, as no medical descriptions of envenomation resulting from its bites seem to exist.

  10. Histological variability in the limb bones of the Asiatic wild ass and its significance for life history inferences.

    Science.gov (United States)

    Nacarino-Meneses, Carmen; Jordana, Xavier; Köhler, Meike

    2016-01-01

    The study of bone growth marks (BGMs) and other histological traits of bone tissue provides insights into the life history of present and past organisms. Important life history traits like longevity or age at maturity, which could be inferred from the analysis of these features, form the basis for estimations of demographic parameters that are essential in ecological and evolutionary studies of vertebrates. Here, we study the intraskeletal histological variability in an ontogenetic series of Asiatic wild ass ( Equus hemionus ) in order to assess the suitability of several skeletal elements to reconstruct the life history strategy of the species. Bone tissue types, vascular canal orientation and BGMs have been analyzed in 35 cross-sections of femur, tibia and metapodial bones of 9 individuals of different sexes, ages and habitats. Our results show that the number of BGMs recorded by the different limb bones varies within the same specimen. Our study supports that the femur is the most reliable bone for skeletochronology, as already suggested. Our findings also challenge traditional beliefs with regard to the meaning of deposition of the external fundamental system (EFS). In the Asiatic wild ass, this bone tissue is deposited some time after skeletal maturity and, in the case of the femora, coinciding with the reproductive maturity of the species. The results obtained from this research are not only relevant for future studies in fossil Equus , but could also contribute to improve the conservation strategies of threatened equid species.

  11. Variable Domain N-Linked Glycans Acquired During Antigen-Specific Immune Responses Can Contribute to Immunoglobulin G Antibody Stability

    Directory of Open Access Journals (Sweden)

    Fleur S. van de Bovenkamp

    2018-04-01

    Full Text Available Immunoglobulin G (IgG can contain N-linked glycans in the variable domains, the so-called Fab glycans, in addition to the Fc glycans in the CH2 domains. These Fab glycans are acquired following introduction of N-glycosylation sites during somatic hypermutation and contribute to antibody diversification. We investigated whether Fab glycans may—in addition to affecting antigen binding—contribute to antibody stability. By analyzing thermal unfolding profiles of antibodies with or without Fab glycans, we demonstrate that introduction of Fab glycans can improve antibody stability. Strikingly, removal of Fab glycans naturally acquired during antigen-specific immune responses can deteriorate antibody stability, suggesting in vivo selection of stable, glycosylated antibodies. Collectively, our data show that variable domain N-linked glycans acquired during somatic hypermutation can contribute to IgG antibody stability. These findings indicate that introducing Fab glycans may represent a mechanism to improve therapeutic/diagnostic antibody stability.

  12. Are Simulated and Observed Twentieth Century Tropical Pacific Sea Surface Temperature Trends Significant Relative to Internal Variability?

    Science.gov (United States)

    Coats, S.; Karnauskas, K. B.

    2017-10-01

    Historical trends in the tropical Pacific zonal sea surface temperature gradient (SST gradient) are analyzed herein using 41 climate models (83 simulations) and 5 observational data sets. A linear inverse model is trained on each simulation and observational data set to assess if trends in the SST gradient are significant relative to the stationary statistics of internal variability, as would suggest an important role for external forcings such as anthropogenic greenhouse gasses. None of the 83 simulations have a positive trend in the SST gradient, a strengthening of the climatological SST gradient with more warming in the western than eastern tropical Pacific, as large as the mean trend across the five observational data sets. If the observed trends are anthropogenically forced, this discrepancy suggests that state-of-the-art climate models are not capturing the observed response of the tropical Pacific to anthropogenic forcing, with serious implications for confidence in future climate projections. There are caveats to this interpretation, however, as some climate models have a significant strengthening of the SST gradient between 1900 and 2013 Common Era, though smaller in magnitude than the observational data sets, and the strengthening in three out of five observational data sets is insignificant. When combined with observational uncertainties and the possibility of centennial time scale internal variability not sampled by the linear inverse model, this suggests that confident validation of anthropogenic SST gradient trends in climate models will require further emergence of anthropogenic trends. Regardless, the differences in SST gradient trends between climate models and observational data sets are concerning and motivate the need for process-level validation of the atmosphere-ocean dynamics relevant to climate change in the tropical Pacific.

  13. Transcription-associated mutational pressure in the Parvovirus B19 genome: Reactivated genomes contribute to the variability of viral populations.

    Science.gov (United States)

    Khrustalev, Vladislav Victorovich; Ermalovich, Marina Anatolyevna; Hübschen, Judith M; Khrustaleva, Tatyana Aleksandrovna

    2017-12-21

    In this study we used non-overlapping parts of the two long open reading frames coding for nonstructural (NS) and capsid (VP) proteins of all available sequences of the Parvovirus B19 subgenotype 1a genome and found out that the rates of A to G, C to T and A to T mutations are higher in the first long reading frame (NS) of the virus than in the second one (VP). This difference in mutational pressure directions for two parts of the same viral genome can be explained by the fact of transcription of just the first long reading frame during the lifelong latency in nonerythroid cells. Adenine deamination (producing A to G and A to T mutations) and cytosine deamination (producing C to T mutations) occur more frequently in transcriptional bubbles formed by DNA "plus" strand of the first open reading frame. These mutations can be inherited only in case of reactivation of the infectious virus due to the help of Adenovirus that allows latent Parvovirus B19 to start transcription of the second reading frame and then to replicate its genome by the rolling circle mechanism using the specific origin. Results of this study provide evidence that the genomes reactivated from latency make significant contributions to the variability of Parvovirus B19. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Perioperative Variables Contributing to the Rupture of Intracranial Aneurysm: An Update

    Directory of Open Access Journals (Sweden)

    Tumul Chowdhury

    2013-01-01

    Full Text Available Background. Perioperative aneurysm rupture (PAR is one of the most dreaded complications of intracranial aneurysms, and approximately 80% of nontraumatic SAHs are related to such PAR aneurysms. The literature is currently scant and even controversial regarding the issues of various contributory factors on different phases of perioperative period. Thus this paper highlights the current understanding of various risk factors, variables, and outcomes in relation to PAR and try to summarize the current knowledge. Method. We have performed a PubMed search (1 January 1991–31 December 2012 using search terms including “cerebral aneurysm,” “intracranial aneurysm,” and “intraoperative/perioperative rupture.” Results. Various risk factors are summarized in relation to different phases of perioperative period and their relationship with outcome is also highlighted. There exist many well-known preoperative variables which are responsible for the highest percentage of PAR. The role of other variables in the intraoperative/postoperative period is not well known; however, these factors may have important contributory roles in aneurysm rupture. Preoperative variables mainly include natural course (age, gender, and familial history as well as the pathophysiological factors (size, type, location, comorbidities, and procedure. Previously ruptured aneurysm is associated with rupture in all the phases of perioperative period. On the other hand intraoperative/postoperative variables usually depend upon anesthesia and surgery related factors. Intraoperative rupture during predissection phase is associated with poor outcome while intraoperative rupture at any step during embolization procedure imposes poor outcome. Conclusion. We have tried to create such an initial categorization but know that we cannot scale according to its clinical importance. Thorough understanding of various risk factors and other variables associated with PAR will assist in better

  15. Economic base determination and influence of several variables against contributions percentage of the GDRP in Aceh Besar district

    Science.gov (United States)

    Andayani, Keumala; Miftahuddin

    2018-05-01

    The percentage contribution of Gross Regional Domestic Product (GRDP) in Aceh Besar district is influenced by several leading sectors, such as agriculture, building sector, trade, hotel and restaurant sector, transport and communications, financial sector, leasing and business services, and services sector. Based on the use of Location Quotient (LQ) method and multiple regression model, the effect of labor variables and population to Gross Regional Domestic Product by 2000 constant prices for agriculture and trade. For each addition of one workforce in the trading sector, the trade sector contribution will increase by 0.000014157%. Thus, the trade sector contribution will increase by 0.0000013786% in every addition of one soul of the population. Whereas, for every addition of one human resource in the agricultural sector will be reduced by 0.0002%. In other words, for each addition of one soul of the population will reduce the contribution of the agricultural sector by 0.00008611%.

  16. Contributions of cell growth and biochemical reactions to nongenetic variability of cells.

    NARCIS (Netherlands)

    Schwabe, A.; Bruggeman, F.J.

    2014-01-01

    Cell-to-cell variability in the molecular composition of isogenic, steady-state growing cells arises spontaneously from the inherent stochasticity of intracellular biochemical reactions and cell growth. Here, we present a general decomposition of the total variance in the copy number per cell of a

  17. Macroalgae contribute to nested mosaics of pH variability in a subarctic fjord

    KAUST Repository

    Krause-Jensen, D.; Duarte, Carlos M.; Hendriks, I. E.; Meire, L.; Blicher, M. E.; Marbà , N.; Sejr, M. K.

    2015-01-01

    The Arctic Ocean is considered the most vulnerable ecosystem to ocean acidification, and large-scale assessments of pH and the saturation state for aragonite (Ωarag) have led to the notion that the Arctic Ocean is already close to a corrosive state. In high-latitude coastal waters the regulation of pH and Ωarag is, however, far more complex than offshore because increased biological activity and input of glacial meltwater affect pH. Effects of ocean acidification on calcifiers and non-calcifying phototrophs occupying coastal habitats cannot be derived from extrapolation of current and forecasted offshore conditions, but they require an understanding of the regimes of pH and Ωarag in their coastal habitats. To increase knowledge of the natural variability in pH in the Arctic coastal zone and specifically to test the influence of benthic vegetated habitats, we quantified pH variability in a Greenland fjord in a nested-scale approach. A sensor array logging pH, O2, PAR, temperature and salinity was applied on spatial scales ranging from kilometre scale across the horizontal extension of the fjord; to 100 m scale vertically in the fjord, 10–100 m scale between subtidal habitats with and without kelp forests and between vegetated tidal pools and adjacent vegetated shores; and to centimetre to metre scale within kelp forests and millimetre scale across diffusive boundary layers of macrophyte tissue. In addition, we assessed the temporal variability in pH on diurnal and seasonal scales. Based on pH measurements combined with point samples of total alkalinity, dissolved inorganic carbon and relationships to salinity, we also estimated variability in Ωarag. Results show variability in pH and Ωarag of up to 0.2–0.3 units at several scales, i.e. along the horizontal and vertical extension of the fjord, between seasons and on a diel basis in benthic habitats and within 1 m3 of kelp forest. Vegetated intertidal pools exhibited extreme diel pH variability of > 1.5 units

  18. Macroalgae contribute to nested mosaics of pH variability in a subarctic fjord

    KAUST Repository

    Krause-Jensen, D.

    2015-08-19

    The Arctic Ocean is considered the most vulnerable ecosystem to ocean acidification, and large-scale assessments of pH and the saturation state for aragonite (Ωarag) have led to the notion that the Arctic Ocean is already close to a corrosive state. In high-latitude coastal waters the regulation of pH and Ωarag is, however, far more complex than offshore because increased biological activity and input of glacial meltwater affect pH. Effects of ocean acidification on calcifiers and non-calcifying phototrophs occupying coastal habitats cannot be derived from extrapolation of current and forecasted offshore conditions, but they require an understanding of the regimes of pH and Ωarag in their coastal habitats. To increase knowledge of the natural variability in pH in the Arctic coastal zone and specifically to test the influence of benthic vegetated habitats, we quantified pH variability in a Greenland fjord in a nested-scale approach. A sensor array logging pH, O2, PAR, temperature and salinity was applied on spatial scales ranging from kilometre scale across the horizontal extension of the fjord; to 100 m scale vertically in the fjord, 10–100 m scale between subtidal habitats with and without kelp forests and between vegetated tidal pools and adjacent vegetated shores; and to centimetre to metre scale within kelp forests and millimetre scale across diffusive boundary layers of macrophyte tissue. In addition, we assessed the temporal variability in pH on diurnal and seasonal scales. Based on pH measurements combined with point samples of total alkalinity, dissolved inorganic carbon and relationships to salinity, we also estimated variability in Ωarag. Results show variability in pH and Ωarag of up to 0.2–0.3 units at several scales, i.e. along the horizontal and vertical extension of the fjord, between seasons and on a diel basis in benthic habitats and within 1 m3 of kelp forest. Vegetated intertidal pools exhibited extreme diel pH variability of > 1.5 units

  19. Contribution of LFP dynamics to single-neuron spiking variability in motor cortex during movement execution

    Science.gov (United States)

    Rule, Michael E.; Vargas-Irwin, Carlos; Donoghue, John P.; Truccolo, Wilson

    2015-01-01

    Understanding the sources of variability in single-neuron spiking responses is an important open problem for the theory of neural coding. This variability is thought to result primarily from spontaneous collective dynamics in neuronal networks. Here, we investigate how well collective dynamics reflected in motor cortex local field potentials (LFPs) can account for spiking variability during motor behavior. Neural activity was recorded via microelectrode arrays implanted in ventral and dorsal premotor and primary motor cortices of non-human primates performing naturalistic 3-D reaching and grasping actions. Point process models were used to quantify how well LFP features accounted for spiking variability not explained by the measured 3-D reach and grasp kinematics. LFP features included the instantaneous magnitude, phase and analytic-signal components of narrow band-pass filtered (δ,θ,α,β) LFPs, and analytic signal and amplitude envelope features in higher-frequency bands. Multiband LFP features predicted single-neuron spiking (1ms resolution) with substantial accuracy as assessed via ROC analysis. Notably, however, models including both LFP and kinematics features displayed marginal improvement over kinematics-only models. Furthermore, the small predictive information added by LFP features to kinematic models was redundant to information available in fast-timescale (spiking history. Overall, information in multiband LFP features, although predictive of single-neuron spiking during movement execution, was redundant to information available in movement parameters and spiking history. Our findings suggest that, during movement execution, collective dynamics reflected in motor cortex LFPs primarily relate to sensorimotor processes directly controlling movement output, adding little explanatory power to variability not accounted by movement parameters. PMID:26157365

  20. Contribution of VPS35 genetic variability to LBD in the Flanders-Belgian population

    NARCIS (Netherlands)

    Verstraeten, Aline; Wauters, Eline; Crosiers, David; Meeus, Bram; Corsmit, Ellen; Elinck, Ellen; Mattheijssens, Maria; Peeters, Karin; Cras, Patrick; Pickut, Barbara; Vandenberghe, Rik; Engelborghs, Sebastiaan; De Deyn, Peter Paul; Van Broeckhoven, Christine; Theuns, Jessie

    VPS35 was recently identified as a novel autosomal dominant gene for Parkinson disease. In this study, we aimed to determine the contribution of simple and complex VPS35 variations to the genetic etiology of the spectrum of Lewy body disorders (LBD) in a Flanders-Belgian patient cohort (n = 677). We

  1. Predicting General Academic Performance and Identifying the Differential Contribution of Participating Variables Using Artificial Neural Networks

    Science.gov (United States)

    Musso, Mariel F.; Kyndt, Eva; Cascallar, Eduardo C.; Dochy, Filip

    2013-01-01

    Many studies have explored the contribution of different factors from diverse theoretical perspectives to the explanation of academic performance. These factors have been identified as having important implications not only for the study of learning processes, but also as tools for improving curriculum designs, tutorial systems, and students'…

  2. Adaptive functioning in pediatric epilepsy: contributions of seizure-related variables and parental anxiety.

    Science.gov (United States)

    Kerne, Valerie; Chapieski, Lynn

    2015-02-01

    Young people with epilepsy are less likely to achieve the level of independence attained by their peers. We examined the seizure-related variables that placed a group of 97 pediatric patients with intractable seizures at risk for poor adaptive functioning. Analyses evaluated both the direct effects of the medical variables and indirect effects that were mediated through increased parental anxiety about their child's epilepsy. Higher numbers of anticonvulsants, presence of seizures that secondarily generalize, longer duration of seizure disorder, and younger age at onset were all identified as risk factors for poor adaptive functioning. Depending on the specific behavioral domain of adaptive functioning, the effects were sometimes direct and sometimes indirect. Lower levels of parental education and positive family history of seizures were associated with higher levels of parental anxiety. Interventions that target parental anxiety about seizures may mitigate the deleterious effects of epilepsy on social development. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Contributing to Overall Life Satisfaction: Personality Traits Versus Life Satisfaction Variables Revisited—Is Replication Impossible?

    OpenAIRE

    Bernd Lachmann; Rayna Sariyska; Christopher Kannen; Konrad Błaszkiewicz; Boris Trendafilov; Ionut Andone; Mark Eibes; Alexander Markowetz; Mei Li; Keith M. Kendrick; Christian Montag

    2017-01-01

    Virtually everybody would agree that life satisfaction is of immense importance in everyday life. Thus, it is not surprising that a considerable amount of research using many different methodological approaches has investigated what the best predictors of life satisfaction are. In the present study, we have focused on several key potential influences on life satisfaction including bottom-up and top-down models, cross-cultural effects, and demographic variables. In four independent (large scal...

  4. Contribution of positron emission tomography for the study of response variability to opioid drugs

    International Nuclear Information System (INIS)

    Auvity, Sylvain

    2017-01-01

    There is a high variability between patients in the initial analgesic response to opioid drugs. The chronic use of opioids leads to tolerance and may induce dependence or addiction. Current Positron Emission Tomography (PET) imaging methods, focusing on the impact of opioids on neuronal and synaptic functions, have failed to elucidate the parameters that control this variability of therapeutic response. A wealth of preclinical studies has addressed the possibility for neuro-immune or neuro-pharmacokinetic parameters to control the response to opioid drugs. Dedicated tools are thus required to investigate their impact on the pharmacology of opioid drugs in vivo and test their implication for variability in therapeutic response. The aim of this PhD project was to develop or to evaluate original methods to study the neuro-immune and neuro-pharmacokinetic components of the variability of response to opioid drugs. Opioid drugs were shown to interact with the innate immune System in the central nervous System (CNS) and to modulate the activity of glial cells. Glial cell activity is often hypothesized to modulate the analgesic efficacy of opioids and account for the development of tolerance and dependence. PET imaging using TSPO (Translocator protein 18 kDa) radioligands such as "1"8F-DPA-714 is the most advanced approach to non-invasively study glial cell activation. In nonhuman primates, we showed that acute morphine exposure increased the brain distribution of "1"8F-DPA-714, suggesting glial cell activation. The extent of the increase was linked to the baseline brain distribution of "1"8F-DPA-714, suggesting the presence of priming parameters in controlling the neuro-immune response to morphine exposure. In healthy rats, we showed that morphine-induced tolerance and withdrawal did not detectably increase the brain distribution of "1"8F-DPA-714 as well as the expression of other bio-markers of glial/micro-glial activation. Dedicated methods were then proposed to

  5. Molecular modelling studies of kdr mutations in voltage gated sodium channel revealed significant conformational variations contributing to insecticide resistance.

    Science.gov (United States)

    Yellapu, Nanda Kumar; Gopal, Jeyakodi; Kasinathan, Gunasekaran; Purushothaman, Jambulingam

    2018-06-01

    Voltage gated sodium channels (VGSC) of mosquito vectors are the primary targets of dichlorodiphenyltrichloroethane (DDT) and other synthetic pyrethroids used in public health programmes. The knockdown resistant (kdr) mutations in VGSC are associated with the insecticide resistance especially in Anophelines. The present study is aimed to emphasize and demarcate the impact of three kdr-mutations such as L1014S, L1014F and L1014H on insecticide resistance. The membrane model of sodium transport domain of VGSC (STD-VGSC) was constructed using de novo approach based on domain and trans-membrane predictions. The comparative molecular modelling studies of wild type and mutant models of STD-VGSC revealed that L1014F mutant was observed to be near native to the wild type model in all the respects, but, L1014S and L1014H mutations showed drastic variations in the energy levels, root mean square fluctuations (RMSF) that resulted in conformational variations. The predicted binding sites also showed variable cavity volumes and RMSF in L1014S and L1014H mutants. Further, DDT also found be bound in near native manner to wild type in L1014F mutant and with variable orientation and affinities in L1014S and L1014H mutants. The variations and fluctuations observed in mutant structures explained that each mutation has its specific impact on the conformation of VGSC and its binding with DDT. The study provides new insights into the structure-function-correlations of mutant STD-VGSC structures and demonstrates the role and effects of kdr mutations on insecticide resistance in mosquito vectors.

  6. Ecological Momentary Assessment of Pain, Fatigue, Depressive, and Cognitive Symptoms Reveals Significant Daily Variability in Multiple Sclerosis.

    Science.gov (United States)

    Kratz, Anna L; Murphy, Susan L; Braley, Tiffany J

    2017-11-01

    To describe the daily variability and patterns of pain, fatigue, depressed mood, and cognitive function in persons with multiple sclerosis (MS). Repeated-measures observational study of 7 consecutive days of home monitoring, including ecological momentary assessment (EMA) of symptoms. Multilevel mixed models were used to analyze data. General community. Ambulatory adults (N=107) with MS recruited through the University of Michigan and surrounding community. Not applicable. EMA measures of pain, fatigue, depressed mood, and cognitive function rated on a 0 to 10 scale, collected 5 times a day for 7 days. Cognitive function and depressed mood exhibited more stable within-person patterns than pain and fatigue, which varied considerably within person. All symptoms increased in intensity across the day (all Pfatigue showing the most substantial increase. Notably, this diurnal increase varied by sex and age; women showed a continuous increase from wake to bedtime, whereas fatigue plateaued after 7 pm for men (wake-bed B=1.04, P=.004). For the oldest subgroup, diurnal increases were concentrated to the middle of the day compared with younger subgroups, which showed an earlier onset of fatigue increase and sustained increases until bed time (wake-3 pm B=.04, P=.01; wake-7 pm B=.03, P=.02). Diurnal patterns of cognitive function varied by education; those with advanced college degrees showed a more stable pattern across the day, with significant differences compared with those with bachelor-level degrees in the evening (wake-7 pm B=-.47, P=.02; wake-bed B=-.45, P=.04). Findings suggest that chronic symptoms in MS are not static, even over a short time frame; rather, symptoms-fatigue and pain in particular-vary dynamically across and within days. Incorporation of EMA methods should be considered in the assessment of these chronic MS symptoms to enhance assessment and treatment strategies. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier

  7. TEMPORALLY VARIABLE GEOGRAPHICAL DISTANCE EFFECTS CONTRIBUTE TO THE ASSEMBLY OF ROOT-ASSOCIATED FUNGAL COMMUNITIES

    Directory of Open Access Journals (Sweden)

    Christopher James Barnes

    2016-02-01

    Full Text Available Root-associated fungi are key contributors to ecosystem functioning, however the factors which determine community assembly are still relatively poorly understood. This study simultaneously quantified the roles of geographical distance, environmental heterogeneity and time in determining root-associated fungal community composition at the local scale within a short rotation coppice (SRC willow plantation. Culture independent molecular analyses of the root-associated fungal community suggested a strong but temporally variable effect of geographical distance between fungal communities on composition at the local geographical level. Whilst these distance effects were most prevalent on October communities, soil pH had an effect on structuring of the communities throughout the sampling period. Given the temporal variation in the effects of geographical distance and the environment for shaping root-associated fungal communities, there is clearly need for a temporal component to sampling strategies in future investigations of fungal biogeography.

  8. Metagenome-based diversity analyses suggest a significant contribution of non-cyanobacterial lineages to carbonate precipitation in modern microbialites

    Directory of Open Access Journals (Sweden)

    Purificacion eLopez-Garcia

    2015-08-01

    Full Text Available Cyanobacteria are thought to play a key role in carbonate formation due to their metabolic activity, but other organisms carrying out oxygenic photosynthesis (photosynthetic eukaryotes or other metabolisms (e.g. anoxygenic photosynthesis, sulfate reduction, may also contribute to carbonate formation. To obtain more quantitative information than that provided by more classical PCR-dependent methods, we studied the microbial diversity of microbialites from the Alchichica crater lake (Mexico by mining for 16S/18S rRNA genes in metagenomes obtained by direct sequencing of environmental DNA. We studied samples collected at the Western (AL-W and Northern (AL-N shores of the lake and, at the latter site, along a depth gradient (1, 5, 10 and 15 m depth. The associated microbial communities were mainly composed of bacteria, most of which seemed heterotrophic, whereas archaea were negligible. Eukaryotes composed a relatively minor fraction dominated by photosynthetic lineages, diatoms in AL-W, influenced by Si-rich seepage waters, and green algae in AL-N samples. Members of the Gammaproteobacteria and Alphaproteobacteria classes of Proteobacteria, Cyanobacteria and Bacteroidetes were the most abundant bacterial taxa, followed by Planctomycetes, Deltaproteobacteria (Proteobacteria, Verrucomicrobia, Actinobacteria, Firmicutes and Chloroflexi. Community composition varied among sites and with depth. Although cyanobacteria were the most important bacterial group contributing to the carbonate precipitation potential, photosynthetic eukaryotes, anoxygenic photosynthesizers and sulfate reducers were also very abundant. Cyanobacteria affiliated to Pleurocapsales largely increased with depth. Scanning electron microscopy (SEM observations showed considerable areas of aragonite-encrusted Pleurocapsa-like cyanobacteria at microscale. Multivariate statistical analyses showed a strong positive correlation of Pleurocapsales and Chroococcales with aragonite formation at

  9. Variability in the efficacy of psychopharmaceuticals: contributions from pharmacogenomics, ethnopsychopharmacology, and psychological and psychiatric anthropologies.

    Science.gov (United States)

    Ninnemann, Kristi M

    2012-03-01

    Psychological and psychiatric anthropology have long questioned the universality of psychiatric diagnoses, bringing to light the fluidity of mental disorder, and recognizing that the experience and expression of psychopathology is influenced by complex and interacting genetic, environmental, and cultural factors. The majority of our discussions, however, have remained centered around the role of culture in shaping mental illness: drawing attention to subjective experiences of mental illness and culturally patterned modes of symptom presentation, and interrogating the cogency of universal diagnostic rubrics. Psychological and psychiatric anthropology have yet to robustly engage the broadly assumed universal validity of psychiatric medications and the ways in which they are prescribed and experienced. This article provides an introduction into the fields of pharmacogenomics and ethnopsychopharmacology, areas of inquiry seeking to understand the ways in which genetic variability occurring between, and within, large population groups influences individual ability to metabolize psychotropic medications. This piece further addresses the complex issue of psychopharmaceutical efficacy, stressing the ways in which, just as with psychopathology, medications and their outcomes are likewise influenced by the complex interactions of genes, environment, and culture. Lastly, ways in which anthropology can and should engage with the growing fields of pharmacogenomics and ethnopsychopharmacology are suggested.

  10. Interrater and intrarater agreements of magnetic resonance imaging findings in the lumbar spine: significant variability across degenerative conditions.

    Science.gov (United States)

    Fu, Michael C; Buerba, Rafael A; Long, William D; Blizzard, Daniel J; Lischuk, Andrew W; Haims, Andrew H; Grauer, Jonathan N

    2014-10-01

    agreement. However, when stratified by condition, absolute interrater agreement ranged from 65.1% to 92.0%. Disc hydration, disc space height, and bone marrow changes exhibited the lowest absolute interrater agreements. The absolute intrarater agreement had a narrower range, from 74.5% to 91.5%. Fleiss kappa coefficients ranged from fair-to-substantial agreement (0.282-0.618). Even in a study using standardized evaluation criteria, there was significant variability in the interrater and intrarater agreements of MRI in assessing different degenerative conditions of the lumbar spine. Clinicians should be aware of the condition-specific diagnostic limitations of MRI interpretation. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Spatiotemporal variability and contribution of different aerosol types to the aerosol optical depth over the Eastern Mediterranean

    Directory of Open Access Journals (Sweden)

    A. K. Georgoulias

    2016-11-01

    Full Text Available This study characterizes the spatiotemporal variability and relative contribution of different types of aerosols to the aerosol optical depth (AOD over the Eastern Mediterranean as derived from MODIS (Moderate Resolution Imaging Spectroradiometer Terra (March 2000–December 2012 and Aqua (July 2002–December 2012 satellite instruments. For this purpose, a 0.1° × 0.1° gridded MODIS dataset was compiled and validated against sun photometric observations from the AErosol RObotic NETwork (AERONET. The high spatial resolution and long temporal coverage of the dataset allows for the determination of local hot spots like megacities, medium-sized cities, industrial zones and power plant complexes, seasonal variabilities and decadal averages. The average AOD at 550 nm (AOD550 for the entire region is ∼ 0.22 ± 0.19, with maximum values in summer and seasonal variabilities that can be attributed to precipitation, photochemical production of secondary organic aerosols, transport of pollution and smoke from biomass burning in central and eastern Europe and transport of dust from the Sahara and the Middle East. The MODIS data were analyzed together with data from other satellite sensors, reanalysis projects and a chemistry–aerosol-transport model using an optimized algorithm tailored for the region and capable of estimating the contribution of different aerosol types to the total AOD550. The spatial and temporal variability of anthropogenic, dust and fine-mode natural aerosols over land and anthropogenic, dust and marine aerosols over the sea is examined. The relative contribution of the different aerosol types to the total AOD550 exhibits a low/high seasonal variability over land/sea areas, respectively. Overall, anthropogenic aerosols, dust and fine-mode natural aerosols account for ∼ 51, ∼ 34 and ∼ 15 % of the total AOD550 over land, while, anthropogenic aerosols, dust and marine aerosols account ∼ 40, ∼ 34

  12. De novo fatty acid biosynthesis contributes significantly to establishment of a bioenergetically favorable environment for vaccinia virus infection.

    Directory of Open Access Journals (Sweden)

    Matthew D Greseth

    2014-03-01

    Full Text Available The poxvirus life cycle, although physically autonomous from the host nucleus, is nevertheless dependent upon cellular functions. A requirement for de novo fatty acid biosynthesis was implied by our previous demonstration that cerulenin, a fatty acid synthase inhibitor, impaired vaccinia virus production. Here we show that additional inhibitors of this pathway, TOFA and C75, reduce viral yield significantly, with partial rescue provided by exogenous palmitate, the pathway's end-product. Palmitate's major role during infection is not for phospholipid synthesis or protein palmitoylation. Instead, the mitochondrial import and β-oxidation of palmitate are essential, as shown by the impact of etomoxir and trimetazidine, which target these two processes respectively. Moreover, the impact of these inhibitors is exacerbated in the absence of exogenous glucose, which is otherwise dispensable for infection. In contrast to glucose, glutamine is essential for productive viral infection, providing intermediates that sustain the TCA cycle (anaplerosis. Cumulatively, these data suggest that productive infection requires the mitochondrial β-oxidation of palmitate which drives the TCA cycle and energy production. Additionally, infection causes a significant rise in the cellular oxygen consumption rate (ATP synthesis that is ablated by etomoxir. The biochemical progression of the vaccinia life cycle is not impaired in the presence of TOFA, C75, or etomoxir, although the levels of viral DNA and proteins synthesized are somewhat diminished. However, by reversibly arresting infections at the onset of morphogenesis, and then monitoring virus production after release of the block, we determined that virion assembly is highly sensitive to TOFA and C75. Electron microscopic analysis of cells released into C75 revealed fragmented aggregates of viroplasm which failed to be enclosed by developing virion membranes. Taken together, these data indicate that vaccinia

  13. De novo fatty acid biosynthesis contributes significantly to establishment of a bioenergetically favorable environment for vaccinia virus infection.

    Science.gov (United States)

    Greseth, Matthew D; Traktman, Paula

    2014-03-01

    The poxvirus life cycle, although physically autonomous from the host nucleus, is nevertheless dependent upon cellular functions. A requirement for de novo fatty acid biosynthesis was implied by our previous demonstration that cerulenin, a fatty acid synthase inhibitor, impaired vaccinia virus production. Here we show that additional inhibitors of this pathway, TOFA and C75, reduce viral yield significantly, with partial rescue provided by exogenous palmitate, the pathway's end-product. Palmitate's major role during infection is not for phospholipid synthesis or protein palmitoylation. Instead, the mitochondrial import and β-oxidation of palmitate are essential, as shown by the impact of etomoxir and trimetazidine, which target these two processes respectively. Moreover, the impact of these inhibitors is exacerbated in the absence of exogenous glucose, which is otherwise dispensable for infection. In contrast to glucose, glutamine is essential for productive viral infection, providing intermediates that sustain the TCA cycle (anaplerosis). Cumulatively, these data suggest that productive infection requires the mitochondrial β-oxidation of palmitate which drives the TCA cycle and energy production. Additionally, infection causes a significant rise in the cellular oxygen consumption rate (ATP synthesis) that is ablated by etomoxir. The biochemical progression of the vaccinia life cycle is not impaired in the presence of TOFA, C75, or etomoxir, although the levels of viral DNA and proteins synthesized are somewhat diminished. However, by reversibly arresting infections at the onset of morphogenesis, and then monitoring virus production after release of the block, we determined that virion assembly is highly sensitive to TOFA and C75. Electron microscopic analysis of cells released into C75 revealed fragmented aggregates of viroplasm which failed to be enclosed by developing virion membranes. Taken together, these data indicate that vaccinia infection, and in

  14. Vertical and horizontal variability of PM10 source contributions in Barcelona during SAPUSS

    Directory of Open Access Journals (Sweden)

    M. Brines

    2016-06-01

    Full Text Available During the SAPUSS campaign (Solving Aerosol Problems by Using Synergistic Strategies PM10 samples at 12-hour resolution were simultaneously collected at four monitoring sites located in the urban agglomerate of Barcelona (Spain. A total of 221 samples were collected from 20 September to 20 October 2010. The Road Site (RS site and the Urban Background (UB site were located at street level, whereas the Torre Mapfre (TM and the Torre Collserola (TC sites were located at 150 m a.s.l. by the sea side within the urban area and at 415 m a.s.l. 8 km inland, respectively. For the first time, we are able to report simultaneous PM10 aerosol measurements, allowing us to study aerosol gradients at both horizontal and vertical levels. The complete chemical composition of PM10 was determined on the 221 samples, and factor analysis (positive matrix factorisation, PMF was applied. This resulted in eight factors which were attributed to eight main aerosol sources affecting PM10 concentrations in the studied urban environment: (1 vehicle exhaust and wear (2–9 µg m−3, 10–27 % of PM10 mass on average, (2 road dust (2–4 µg m−3, 8–12 %, (3 mineral dust (5 µg m−3, 13–26 %, (4 aged marine (3–5 µg m−3, 13–20 %, (5 heavy oil (0.4–0.6 µg m−3, 2 %, (6 industrial (1 µg m−3, 3–5 %, (7 sulfate (3–4 µg m−3, 11–17 % and (8 nitrate (4–6 µg m−3, 17–21 %. Three aerosol sources were found to be enhanced at the ground levels (confined within the urban ground levels of the city relative to the upper levels: (1 vehicle exhaust and wear (2.8 higher, (2 road dust (1.8 higher and (3 local urban industries/crafts workshops (1.6 higher. Surprisingly, the other aerosol sources were relatively homogeneous at both horizontal and vertical levels. However, air mass origin and meteorological parameters also played a key role in influencing the variability of the factor

  15. Vertical and horizontal variability of PM10 source contributions in Barcelona during SAPUSS

    Science.gov (United States)

    Brines, Mariola; Dall'Osto, Manuel; Amato, Fulvio; Cruz Minguillón, María; Karanasiou, Angeliki; Alastuey, Andrés; Querol, Xavier

    2016-06-01

    During the SAPUSS campaign (Solving Aerosol Problems by Using Synergistic Strategies) PM10 samples at 12-hour resolution were simultaneously collected at four monitoring sites located in the urban agglomerate of Barcelona (Spain). A total of 221 samples were collected from 20 September to 20 October 2010. The Road Site (RS) site and the Urban Background (UB) site were located at street level, whereas the Torre Mapfre (TM) and the Torre Collserola (TC) sites were located at 150 m a.s.l. by the sea side within the urban area and at 415 m a.s.l. 8 km inland, respectively. For the first time, we are able to report simultaneous PM10 aerosol measurements, allowing us to study aerosol gradients at both horizontal and vertical levels. The complete chemical composition of PM10 was determined on the 221 samples, and factor analysis (positive matrix factorisation, PMF) was applied. This resulted in eight factors which were attributed to eight main aerosol sources affecting PM10 concentrations in the studied urban environment: (1) vehicle exhaust and wear (2-9 µg m-3, 10-27 % of PM10 mass on average), (2) road dust (2-4 µg m-3, 8-12 %), (3) mineral dust (5 µg m-3, 13-26 %), (4) aged marine (3-5 µg m-3, 13-20 %), (5) heavy oil (0.4-0.6 µg m-3, 2 %), (6) industrial (1 µg m-3, 3-5 %), (7) sulfate (3-4 µg m-3, 11-17 %) and (8) nitrate (4-6 µg m-3, 17-21 %). Three aerosol sources were found to be enhanced at the ground levels (confined within the urban ground levels of the city) relative to the upper levels: (1) vehicle exhaust and wear (2.8 higher), (2) road dust (1.8 higher) and (3) local urban industries/crafts workshops (1.6 higher). Surprisingly, the other aerosol sources were relatively homogeneous at both horizontal and vertical levels. However, air mass origin and meteorological parameters also played a key role in influencing the variability of the factor concentrations. The mineral dust and aged marine factors were found to be a mixture of natural and

  16. Self-selection contributes significantly to the lower adiposity offaster, longer-distanced, male and female walkers

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Paul T.

    2006-01-06

    Although cross-sectional studies show active individuals areleaner than their sedentary counterparts, it remains to be determined towhat extent this is due to initially leaner men and women choosing toexercise longer and more intensely (self-selection bias). In this reportwalking volume (weekly distance) and intensity (speed) were compared tocurrent BMI (BMIcurrent) and BMI at the start of walking (BMIstarting) in20,353 women and 5,174 men who had walked regularly for exercise for 7.2and 10.6 years,respectively. The relationships of BMIcurrent andBMIstarting with distance and intensity were nonlinear (convex). Onaverage, BMIstarting explained>70 percent of the association betweenBMIcurrent and intensity, and 40 percent and 17 percent of theassociation between BMIcurrent and distance in women and men,respectively. Although the declines in BMIcurrent with distance andintensity were greater among fatter than leaner individuals, the portionsattributable to BMIstarting remained relatively constant regardless offatness. Thus self-selection bias accounts for most of the decline in BMIwith walking intensity and smaller albeit significant proportions of thedecline with distance. This demonstration of self-selection is germane toother cross-sectional comparisons in epidemiological research, givenself-selection is unlikely to be limited to weight or peculiar tophysical activity.

  17. Dermal exposure to jet fuel JP-8 significantly contributes to the production of urinary naphthols in fuel-cell maintenance workers.

    Science.gov (United States)

    Chao, Yi-Chun E; Kupper, Lawrence L; Serdar, Berrin; Egeghy, Peter P; Rappaport, Stephen M; Nylander-French, Leena A

    2006-02-01

    Jet propulsion fuel 8 (JP-8) is the major jet fuel used worldwide and has been recognized as a major source of chemical exposure, both inhalation and dermal, for fuel-cell maintenance workers. We investigated the contributions of dermal and inhalation exposure to JP-8 to the total body dose of U.S. Air Force fuel-cell maintenance workers using naphthalene as a surrogate for JP-8 exposure. Dermal, breathing zone, and exhaled breath measurements of naphthalene were obtained using tape-strip sampling, passive monitoring, and glass bulbs, respectively. Levels of urinary 1- and 2-naphthols were determined in urine samples and used as biomarkers of JP-8 exposure. Multiple linear regression analyses were conducted to investigate the relative contributions of dermal and inhalation exposure to JP-8, and demographic and work-related covariates, to the levels of urinary naphthols. Our results show that both inhalation exposure and smoking significantly contributed to urinary 1-naphthol levels. The contribution of dermal exposure was significantly associated with levels of urinary 2-naphthol but not with urinary 1-naphthol among fuel-cell maintenance workers who wore supplied-air respirators. We conclude that dermal exposure to JP-8 significantly contributes to the systemic dose and affects the levels of urinary naphthalene metabolites. Future work on dermal xenobiotic metabolism and toxicokinetic studies are warranted in order to gain additional knowledge on naphthalene metabolism in the skin and the contribution to systemic exposure.

  18. Brief Communication: Upper Air Relaxation in RACMO2 Significantly Improves Modelled Interannual Surface Mass Balance Variability in Antarctica

    Science.gov (United States)

    van de Berg, W. J.; Medley, B.

    2016-01-01

    The Regional Atmospheric Climate Model (RACMO2) has been a powerful tool for improving surface mass balance (SMB) estimates from GCMs or reanalyses. However, new yearly SMB observations for West Antarctica show that the modelled interannual variability in SMB is poorly simulated by RACMO2, in contrast to ERA-Interim, which resolves this variability well. In an attempt to remedy RACMO2 performance, we included additional upper-air relaxation (UAR) in RACMO2. With UAR, the correlation to observations is similar for RACMO2 and ERA-Interim. The spatial SMB patterns and ice-sheet-integrated SMB modelled using UAR remain very similar to the estimates of RACMO2 without UAR. We only observe an upstream smoothing of precipitation in regions with very steep topography like the Antarctic Peninsula. We conclude that UAR is a useful improvement for regional climate model simulations, although results in regions with steep topography should be treated with care.

  19. IDENTIFICATION OF THOSE VARIABLES THAT HAVE A SIGNIFICANT INFLUENCE ON THE EXPECTED NUMBER OF DAYS OF STAYING IN THE CENTRE DEVELOPMENT REGION OF ROMANIA

    Directory of Open Access Journals (Sweden)

    Erika KULCSÁR

    2010-06-01

    Full Text Available I started from the assumption that there are more variables that have a significant influence on the expected number of days of staying in the Centre Development Region. To identify those variables this paper includes the analysis of variance with two variables that are not interacting, in this case the dependent variable is the question "How many days did you plan to stay in Centre Development Region?" and the independent variables are: "What is the purpose of your stay?" "What is the highest level of education?". Given that there are cases when interactions occur between variables, I also analyzed the interaction effects between the two independent variables. The paper also includes an ANOVA analysis with three variables between which interactions relationships occur. After identifying the dependency relations between the variables I found that the inclusion of the third variable, namely the "Marital status" of respondents, adds value to the model. Following the results obtained by ANOVA analysis, I identified those socio-demographic characteristics that, in my opinion, companies that operate on tourist market in the Center Development Region should consider when fundamenting marketing strategies in tourism.

  20. Using k-dependence causal forest to mine the most significant dependency relationships among clinical variables for thyroid disease diagnosis.

    Directory of Open Access Journals (Sweden)

    LiMin Wang

    Full Text Available Numerous data mining models have been proposed to construct computer-aided medical expert systems. Bayesian network classifiers (BNCs are more distinct and understandable than other models. To graphically describe the dependency relationships among clinical variables for thyroid disease diagnosis and ensure the rationality of the diagnosis results, the proposed k-dependence causal forest (KCF model generates a series of submodels in the framework of maximum spanning tree (MST and demonstrates stronger dependence representation. Friedman test on 12 UCI datasets shows that KCF has classification accuracy advantage over the other state-of-the-art BNCs, such as Naive Bayes, tree augmented Naive Bayes, and k-dependence Bayesian classifier. Our extensive experimental comparison on 4 medical datasets also proves the feasibility and effectiveness of KCF in terms of sensitivity and specificity.

  1. Chromosomal radiosensitivity: a study of the chromosomal G2 assay in human blood lymphocytes indicating significant inter-individual variability

    International Nuclear Information System (INIS)

    Smart, V.; Curwen, G.B.; Whitehouse, C.A.; Edwards, A.; Tawn, E.J.

    2003-01-01

    The G 2 chromosomal radiosensitivity assay is a technically demanding assay. To ensure that it is reproducible in our laboratory, we have examined the effects of storage and culture conditions by applying the assay to a group of healthy controls and determined the extent of intra- and inter-individual variations. Nineteen different individuals provided one or more blood samples resulting in a total of 57 successful tests. Multiple cultures from a single blood sample showed no statistically significant difference in the number of chromatid type aberrations between cultures. A 24 h delay prior to culturing the lymphocytes did not significantly affect the induced G 2 score. Intra-individual variation was not statistically significant in seven out of nine individuals. Inter-individual variation was highly statistically significant (P<0.001), indicating that there is a real difference between individuals in the response to radiation using this assay

  2. The relative contributions of tropical Pacific sea surface temperatures and atmospheric internal variability to the recent global warming hiatus

    Science.gov (United States)

    Deser, Clara; Guo, Ruixia; Lehner, Flavio

    2017-08-01

    The recent slowdown in global mean surface temperature (GMST) warming during boreal winter is examined from a regional perspective using 10-member initial-condition ensembles with two global coupled climate models in which observed tropical Pacific sea surface temperature anomalies (TPAC SSTAs) and radiative forcings are specified. Both models show considerable diversity in their surface air temperature (SAT) trend patterns across the members, attesting to the importance of internal variability beyond the tropical Pacific that is superimposed upon the response to TPAC SSTA and radiative forcing. Only one model shows a close relationship between the realism of its simulated GMST trends and SAT trend patterns. In this model, Eurasian cooling plays a dominant role in determining the GMST trend amplitude, just as in nature. In the most realistic member, intrinsic atmospheric dynamics and teleconnections forced by TPAC SSTA cause cooling over Eurasia (and North America), and contribute equally to its GMST trend.

  3. Seasonal variability in physiological and anatomical traits contributes to invasion success of Prosopis juliflora in tropical dry forest.

    Science.gov (United States)

    Oliveira, Marciel T; Souza, Gustavo M; Pereira, Silvia; Oliveira, Deborah A S; Figueiredo-Lima, Karla V; Arruda, Emília; Santos, Mauro G

    2017-03-01

    We investigated whether there were consistent differences in the physiological and anatomical traits and phenotypic variability of an invasive (Prosopis juliflora (Sw.) DC.) and native species (Anadenanthera colubrina (Vell.) Brenan) in response to seasonality in a tropical dry forest. The water potential, organic solutes, gas exchange, enzymes of the antioxidant system, products of oxidative stress and anatomical parameters were evaluated in both species in response to seasonality. An analysis of physiological responses indicated that the invasive P. juliflora exhibited higher response in net photosynthetic rate to that of the native species between seasons. Higher values of water potential of the invasive species than those of the native species in the dry season indicate a more efficient mechanism for water regulation in the invasive species. The invasive species exhibits a thicker cuticle and trichomes, which can reduce transpiration. In combination, the increased epidermal thickness and the decreased thickness of the parenchyma in the dry season may contribute to water saving. Our data suggest a higher variability in anatomical traits in the invasive species as a response to seasonality, whereas physiological traits did not present a clear pattern of response. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. HIV-1 infection during pregnancy and in children : significance of HIV-1 variability and the placental barrier

    OpenAIRE

    Casper, Charlotte

    2001-01-01

    With the global increase in human immunodeficiency virus 1 (HIV-1) infection in women of childbearing age, there has also been an alarming increase in the number of mother-to-child transmissions of HIV-1. Although antiretroviral therapy and Cesarian section have been demonstrated to significantly decrease the vertical transmission rate of , these interventions are not widely available in the developing world. Therefore, studies of the mechanisms of vertical transmission are ...

  5. Examining the Contribution of Physical Education and Sports Courses in the Secondary School to the Sportsmanship Behaviours in Terms of Some Variables

    Directory of Open Access Journals (Sweden)

    Serkan HACICAFEROĞLU

    2015-08-01

    Full Text Available This study was carried out in order to determine the contribution of the physical education and sports classes in the secondary school to the sportsmanship behaviours in terms of some variables. The population of the study, which was carried out using a general screening model, consists of students from the government - dependent secondary schools in the county, of Malatya Battalgazi, and its sampling consists of 670 students, studying at “Atatürk, Barbaros, Türk Telekom, Türkiye’m and Vakifbank” public secondary schools in the city centre of Malatya, chosen from the these schools by a random method. In the research, "Physical Education Courses Sportsmanship Behaviours Scale" is used as a data collec ting tool. Analysis of data obtained from the research was conducted with the help of a SPSS 20 package program and arithmetic mean, t - test and one - way analysis of variance (ANOVA were used in the calculation. As the result of the study, relying on the an swers the students have given to the scale it has been determined that the overall arithmetic mean of the scale was lower than expected, that the views on the contribution of the physical education and sports classes to sportsmanship behaviours were equiva lent to each other depending on the demographic variables of gender and father’s education level, however, there were significant differences among students depending on the grade level.

  6. Contribution to the discussion of P.M. Fayers and David J. Hand: Causal variables, indicator variables and measurement scales: an example from quality of life

    DEFF Research Database (Denmark)

    Keiding, Niels

    2002-01-01

    Causal variables; Clinimetric scales; Composite scales; Construct validity; Measurement scales; Multi-item scales; Quality-of-life instruments......Causal variables; Clinimetric scales; Composite scales; Construct validity; Measurement scales; Multi-item scales; Quality-of-life instruments...

  7. Prognostic Significance of Blood Pressure Variability on Beat-to-Beat Monitoring After Transient Ischemic Attack and Stroke.

    Science.gov (United States)

    Webb, Alastair J S; Mazzucco, Sara; Li, Linxin; Rothwell, Peter M

    2018-01-01

    Visit-to-visit and day-to-day blood pressure (BP) variability (BPV) predict an increased risk of cardiovascular events but only reflect 1 form of BPV. Beat-to-beat BPV can be rapidly assessed and might also be predictive. In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (Oxford Vascular Study), BPV (coefficient of variation) was measured beat-to-beat for 5 minutes (Finometer), day-to-day for 1 week on home monitoring (3 readings, 3× daily), and on awake ambulatory BP monitoring. BPV after 1-month standard treatment was related (Cox proportional hazards) to recurrent stroke and cardiovascular events for 2 to 5 years, adjusted for mean systolic BP. Among 520 patients, 26 had inadequate beat-to-beat recordings, and 22 patients were in atrial fibrillation. Four hundred five patients had all forms of monitoring. Beat-to-beat BPV predicted recurrent stroke and cardiovascular events independently of mean systolic BP (hazard ratio per group SD, stroke: 1.47 [1.12-1.91]; P =0.005; cardiovascular events: 1.41 [1.08-1.83]; P =0.01), including after adjustment for age and sex (stroke: 1.47 [1.12-1.92]; P =0.005) and all risk factors (1.40 [1.00-1.94]; P =0.047). Day-to-day BPV was less strongly associated with stroke (adjusted hazard ratio, 1.29 [0.97-1.71]; P =0.08) but similarly with cardiovascular events (1.41 [1.09-1.83]; P =0.009). BPV on awake ambulatory BP monitoring was nonpredictive (stroke: 0.89 [0.59-1.35]; P =0.59; cardiovascular events: 1.08 [0.77-1.52]; P =0.65). Despite a weak correlation ( r =0.119; P =0.02), beat-to-beat BPV was associated with risk of recurrent stroke independently of day-to-day BPV (1.41 [1.05-1.90]; P =0.02). Beat-to-beat BPV predicted recurrent stroke and cardiovascular events, independently of mean systolic BP and risk factors but short-term BPV on ambulatory BP monitoring did not. Beat-to-beat BPV may be a useful additional marker of cardiovascular risk. © 2017 The Authors.

  8. Identifying significant factors which can contribute to successful transitions from school to lasting employment affiliation for pupils in vocational training programs

    OpenAIRE

    Nils Breilid; Eva Dyrnes

    2017-01-01

    Introduction: This study deals with young people receiving special needs education in schools and their transition to lasting employment in private or public sector. Through a qualitative approach, the article aims at “identifying significant factors which can, contribute to successful transitions from school to lasting employment affiliation for pupils in vocational training programs”Theoretical approach: The theoretical approach of this article is descriptions and interpretation of the Norw...

  9. How Do Different Cognitive and Linguistic Variables Contribute to Reading in Arabic? A Cross-Sectional Study from First to Sixth Grade

    Science.gov (United States)

    Asadi, Ibrahim A.; Khateb, Asaid; Ibrahim, Raphiq; Taha, Haitham

    2017-01-01

    The contribution of linguistic and cognitive variables to reading processes might vary depending on the particularities of the languages studied. This view is thought to be particularly true for Arabic which is a diglossic language and has particular orthographic and morpho-syntactic systems. This cross-sectional study examined the contribution of…

  10. Unbiased proteomics analysis demonstrates significant variability in mucosal immune factor expression depending on the site and method of collection.

    Directory of Open Access Journals (Sweden)

    Kenzie M Birse

    Full Text Available Female genital tract secretions are commonly sampled by lavage of the ectocervix and vaginal vault or via a sponge inserted into the endocervix for evaluating inflammation status and immune factors critical for HIV microbicide and vaccine studies. This study uses a proteomics approach to comprehensively compare the efficacy of these methods, which sample from different compartments of the female genital tract, for the collection of immune factors. Matching sponge and lavage samples were collected from 10 healthy women and were analyzed by tandem mass spectrometry. Data was analyzed by a combination of differential protein expression analysis, hierarchical clustering and pathway analysis. Of the 385 proteins identified, endocervical sponge samples collected nearly twice as many unique proteins as cervicovaginal lavage (111 vs. 61 with 55% of proteins common to both (213. Each method/site identified 73 unique proteins that have roles in host immunity according to their gene ontology. Sponge samples enriched for specific inflammation pathways including acute phase response proteins (p = 3.37×10(-24 and LXR/RXR immune activation pathways (p = 8.82×10(-22 while the role IL-17A in psoriasis pathway (p = 5.98×10(-4 and the complement system pathway (p = 3.91×10(-3 were enriched in lavage samples. Many host defense factors were differentially enriched (p<0.05 between sites including known/potential antimicrobial factors (n = 21, S100 proteins (n = 9, and immune regulatory factors such as serpins (n = 7. Immunoglobulins (n = 6 were collected at comparable levels in abundance in each site although 25% of those identified were unique to sponge samples. This study demonstrates significant differences in types and quantities of immune factors and inflammation pathways collected by each sampling technique. Therefore, clinical studies that measure mucosal immune activation or factors assessing HIV transmission should utilize

  11. The co registration of initial PET on the CT-radiotherapy reduces significantly the variabilities of anatomo-clinical target volume in the child hodgkin disease

    International Nuclear Information System (INIS)

    Metwally, H.; Blouet, A.; David, I.; Rives, M.; Izar, F.; Courbon, F.; Filleron, T.; Laprie, A.; Plat, G.; Vial, J.

    2009-01-01

    It exists a great interobserver variability for the anatomo-clinical target volume (C.T.V.) definition in children suffering of Hodgkin disease. In this study, the co-registration of the PET with F.D.G. on the planning computed tomography has significantly lead to a greater coherence in the clinical target volume definition. (N.C.)

  12. Identifying significant factors which can contribute to successful transitions from school to lasting employment affiliation for pupils in vocational training programs

    Directory of Open Access Journals (Sweden)

    Nils Breilid

    2017-06-01

    Full Text Available Introduction: This study deals with young people receiving special needs education in schools and their transition to lasting employment in private or public sector. Through a qualitative approach, the article aims at “identifying significant factors which can, contribute to successful transitions from school to lasting employment affiliation for pupils in vocational training programs”Theoretical approach: The theoretical approach of this article is descriptions and interpretation of the Norwegian educational legislation and the theory of «empowerment». These theoretical perspectives will be included in the empirical discussion. Method: The methodological approach is qualitative. Through four semi-structured interviews of young informants who have completed upper secondary school in a vocational education program, and have had a minimum of one-year training in an enterprise. Thematic analysis of the data is conducted with the application of NVivo 11, a computer program that is suitable for qualitative data-analysis and mixed research methods.Results and discussion: Through thematic analysis of the data, we found three significant factors contributing to successful transitions from school to lasting employment:      a Application and development of the pupil’s competence - mastery and meaning      b The significance of relations, communication and well-functioning socio-ecological          networks      c The importance of pupil participation and involvement in decision making

  13. An Attempt To Estimate The Contribution Of Variability Of Wetland Extent On The Variability Of The Atmospheric Methane Growth Rate In The Years 1993-2000.

    Science.gov (United States)

    Ringeval, B.; de Noblet-Ducoudre, N.; Prigent, C.; Bousquet, P.

    2006-12-01

    The atmospheric methane growth rate presents lots of seasonal and year-to-year variations. Large uncertainties still exist in the relative part of differents sources and sinks on these variations. We have considered, in this study, the main natural sources of methane and the supposed main variable source, i.e. wetlands, and tried to simulate the variations of their emissions considering the variability of the wetland extent and of the climate. For this study, we use the methane emission model of Walter et al. (2001) and the quantification of the flooded areas for the years 1993-2000 obtained with a suite of satellite observations by Prigent et al. (2001). The data necessary to the Walter's model are obtained with simulation of a dynamic global vegetation model ORCHIDEE (Krinner et al. (2005)) constrained by the NCC climate data (Ngo-Duc et al. (2005)) and after imposing a water-saturated soil to approach productivity of wetlands. We calculate global annual methane emissions from wetlands to be 400 Tg per year, that is higher than previous results obtained with fixed wetland extent. Simulations are realised to estimate the part of variability in the emissions explained by the variability of the wetland extent. It seems that the year-to-year emission variability is mainly explained by the interannual variability of wetland extent. The seasonnal variability is explained for 75% in the tropics and only for 40% in the north of 30°N by variability of wetlands extend. Finally, we compare results with a top-down approach of Bousquet et al.(2006).

  14. [Bibliometric analysis of IBERPOC and EPI-SCAN studies. Contribution of the smoking variable on the iberpoc study].

    Science.gov (United States)

    de Granda-Orive, J I; Alonso-Arroyo, A; López-Padilla, D; Segrelles-Calvo, G; Jiménez-Ruiz, C A; Solano-Reina, S

    2018-03-01

    The aim of this study was to perform a bibliometric analysis of EPI-SCAN and IBERPOC studies using the Science Citation Index and Scopus databases, and to determine the overall impact with the impact of smoking on IBERPOC as a secondary objective. A general searching was conducted in Science Citation Index-Expanded through the Web of Science (WoS) (Thomson Reuters) platform and Scopus on 23 March 2015. The search strategy included the terms "iberpoc" OR "episcan" was performed on 15 October 2015. A total of 24 publications were obtained; 13 from IBERPOC study (9 on "COPD" and 4 for "tobacco"), with 11 from the EPI-SCAN (All COPD) study. A total of 841 WoS citations were obtained (445 IBERPOC [99 of tobacco]), and 1,442 from Scopus (963 IBERPOC [144 tobacco]). The theme "tobacco" contributed with 22.24% and 14.95% of total citations in WoS and Scopus, respectively to the IBERPOC study. It was found that Scopus citations were newer, and a similar impact from both WoS studies was detected, although the IBERPOC impact was greater in Scopus. Collaborative networks of institutions and authors of both studies were identified. There is an important productivity and impact of both studies. Scopus citations are newer than those in WoS. The "tobacco" variable added IBERPOC impact and visibility. There was high density, accessibility, and cohesion in collaborative networks of both studies. Copyright © 2017 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Identification of a Major Locus Contributing to Erythrocyte 2,3-Diphosphoglycerate Variability in Hooded (Long-Evans) Rats

    Science.gov (United States)

    Noble, N. A.; Brewer, G. J.

    1977-01-01

    The erythrocyte glycolytic intermediate 2,3-diphosphoglycerate (DPG) and adenosine triphosphate (ATP) play an important role in oxygen transport and delivery by binding to hemoglobin (Hb) and reducing its affinity for oxygen. Considerable quantitative variability in the levels of DPG and ATP exists in human populations and in a population of hooded (Long-Evans) rats we have studied. This paper presents the results of studies on the genetic component of DPG-level variation in an outbred population of hooded rats. Beginning with about 100 rats, a two-way selection experiment was initiated. Pairs of rats with the highest DPG levels were mated to produce a High-DPG rat strain and animals with the lowest DPG levels were mated to produce a Low-DPG strain. Mean DPG levels responded rapidly to selection and, from generation 3 on, the differences between strain means were highly significant. Ten High-DPG strain rats were intercrossed with 10 Low-DPG strain rats of generation 10 to produce an F1 generation in which the DPG levels were almost as high as those of High-DPG animals. This indicates partial dominance of High-DPG alleles. The F2 DPG-level distribution showed two distinct subpopulations. The high DPG subpopulation contained three times as many animals as the low DPG subpopulation. From these results and the statistical analyses performed, it was concluded that the DPG differences between strains were due to an allelic difference at one major locus, the allele carried by the High-DPG strain showing partial dominance over the allele carried by the Low-DPG strain. It appears that this locus may also effect ATP levels to a large extent and is polymorphic in hooded rat populations. Identification of this locus gives us a useful tool for studies of the physiological effects of DPG variability, as well as providing an example of a major gene effect in a quantitatively varying trait. PMID:863239

  16. Contribution of the autonomic nervous system to blood pressure and heart rate variability changes in early experimental hyperthyroidism.

    Science.gov (United States)

    Safa-Tisseront, V; Ponchon, P; Laude, D; Elghozi, J L

    1998-07-10

    A great deal of uncertainty persists regarding the exact nature of the interaction between autonomic nervous system activity and thyroid hormones in the control of heart rate and blood pressure. We now report on thyrotoxicosis produced by daily intraperitoneal (i.p.) injection of L-thyroxine (0.5 mg/kg body wt. in 1 ml of 5 mM NaOH for 5 days). Control rats received i.p. daily injections of the thyroxine solvent. In order to estimate the degree of autonomic activation in hyperthyroidism, specific blockers were administered intravenously: atropine (0.5 mg/kg), prazosin (1 mg/kg), atenolol (1 mg/kg) or the combination of atenolol and atropine. A jet of air was administered in other animals to induce sympathoactivation. Eight animals were studied in each group. The dose and duration of L-thyroxine treatment was sufficient to induce a significant degree of hyperthyroidism with accompanying tachycardia, systolic blood pressure elevation, increased pulse pressure, cardiac hypertrophy, weight loss, tachypnea and hyperthermia. In addition, the intrinsic heart period observed after double blockade (atenolol + atropine) was markedly decreased after treatment with L-thyroxine (121.5+/-3.6 ms vs. 141.2+/-3.7 ms, P hyperthyroidism and in these rats the jet of air did not significantly affect the heart period level. The thyrotoxicosis was associated with a reduction of the 0.4 Hz component of blood pressure variability (analyses on 102.4 s segments, modulus 1.10+/-0.07 vs. 1.41+/-0.06 mm Hg, P hyperthyroidism. The marked rise in the intrinsic heart rate could be the main determinant of tachycardia. The blood pressure elevation may reflexly induce vagal activation and sympathetic (vascular and cardiac) inhibition.

  17. The (InSignificance of Socio-Demographic Factors as Possible Determinants of Vietnamese Social Scientists’ Contribution-Adjusted Productivity: Preliminary Results from 2008–2017 Scopus Data

    Directory of Open Access Journals (Sweden)

    Thu-Trang Vuong

    2017-12-01

    Full Text Available As collaboration has become widespread in academia, and the number of authors per article has increased, the publication count is no longer an accurate indicator of scientific output in many cases. To overcome this limitation, this study defined and computed a relative count of publications called ‘CP’ (credit-based contribution points, based on the sequence-determines-credit (SDC method, which takes into account the level of contribution of each author. Analyses were done on a sample of 410 Vietnamese social scientists whose publications were indexed in the Scopus database during 2008–2017. The results showed that the average CP of Vietnamese researchers in the field of social sciences and humanities is very low: more than 88% of authors have a CP less than five over a span 10 years. Researchers with a higher CP were mostly 40–50 years old; however, even for this sub-group, the mean CP was only 3.07. Multiple attributes of first-authorship—including knowledge, research skills, and critical thinking—could boost the CP by a ratio of 1:1.06. There is no evidence of gender differences in productivity, however, there is a regional difference. These findings offer significant insights into the education system in regard to science and technology, namely policy implications for science funding and management strategies for research funds.

  18. Continuous distending pressure effects on variables contributing to oxygenation in healthy and ARDS model pigs during HFOV

    Science.gov (United States)

    Laviola, Marianna; Hajny, Ondrej; Roubik, Karel

    2014-10-01

    High frequency oscillatory ventilation (HFOV) is an alternative mode of mechanical ventilation. HFOV has been shown to provide adequate ventilation and oxygenation in acute respiratory distress syndrome (ARDS) patients and may represent an effective lung-protective ventilation in patients where conventional ventilation is failing. The aim of this study is to evaluate effects of continuous distending pressure (CDP) on variables that contribute to the oxygenation in healthy and ARDS lung model pigs. Methods. In order to simulate a lung disease, lung injury was induced by lavage with normal saline with detergent in three pigs. HFOV ventilation was applied before and after the lung lavage. CDP was stepwise increased by 2 cmH2O, until the maximum CDP (before the lung lavage 32 cmH2O and after the lung lavage 42 cmH2O) and then it was stepwise decreased by 2 cmH2O to the initial value. In this paper we analyzed the following parameters acquired during our experiments: partial pressure of oxygen in arterial blood (PaO2), cardiac output (CO) and mixed venous blood oxygen saturation (SvO2). In order to find how both PaO2 and CO affected SvO2 during the increase of CDP before and after lavage, a nonlinear regression fitting of the response in SvO2 on the predictors (PaO2 and CO) was implemented. Results. Before the lavage, with increasing of CDP, PaO2 remained constant, CO strongly decreased and SvO2 slightly decreased. After the lavage, with increasing of CDP, PaO2 strongly increased, CO decreased and SvO2 increased. So, development of SvO2 followed the PaO2 and CO trends. Changes in PaO2 and CO occur at decisive CDP step and it was much higher after the lung lavage compared to the healthy lungs. The implemented nonlinear model gives a good goodness of fitting in all three pigs. The values of PaO2 and CO estimated coefficients changed at the same decisive step of CDP identified by the trends. Also the algorithm identified a CDP step much higher after the lung lavage

  19. Economic and safe operation of isolated systems with significant contribution from renewable energy sources; Operacao economica e segura de sistemas isolados com grande penetracao de energias renovaveis

    Energy Technology Data Exchange (ETDEWEB)

    Matos, M.A. [Instituto de Engenharia de Sistemas e Computadores (INESC), Porto (Portugal); Vlachos, A; Androutsos, A. [NTUA, Atenas (Greece); Bakirtzis, T. [AUTH, Salonica (Greece); Gigantidou, A. [DEI, Heraklio (Greece). E-mail: mmatos@inescn.pt; avlachos@power.ece.ntua.gr; bakiana@eng.auth.gr; deh_kkf@iraklio.netor.gr

    1999-07-01

    Medium and large size isolated systems with a significant contribution from renewable energy sources, specifically eolic energy, are not conveniently operated at the present, neither by the conventional ways of unit commitment/load dispatcher nor by the simplified procedures used in the small isolated power networks. This paper presents a new approaching, in the CARE framework which is financially supported by the European Union through the EEN-JOULE assistance program. The principal idea is to perform unit commitment on-line in the same dispatching cycle, by using the load forecasting and the more recent wind power. The process includes dynamic safety fast evaluation and a module for helping the decision making.

  20. Sexual Satisfaction and Sexual Reactivity in Infertile Women: The Contribution of The Dyadic Functioning and Clinical Variables

    Directory of Open Access Journals (Sweden)

    Anna Czyżkowska

    2016-12-01

    Full Text Available Background: Infertility is a factor which has been linked to higher prevalence of sexual dysfunctions in women; however, ambiguous results have been reported about the impact of infertility on women’s sexual satisfaction. The purpose of this study was to compare sexual and dyadic functioning in infertile and fertile women. Furthermore, the associations between sexual variables and clinical variables (depressive symptoms, period trying to conceive, and treatment period were assessed in infertile women sample. Materials and Methods: The cross-sectional study involved 50 women with the history of infertility and 50 fertile women recruited from the general population. The Sexual Satisfaction Scale (SSS, Mell-Krat Scale (women’s version, Family Assessment Measure (FAM-III, and Beck Depression Inventory (BDI were administered to all participants. Results: Infertile women reported lower sexual satisfaction and more maladaptive patterns of dyadic functioning in comparison to the control group. As many as 45 (90% of infertile women, compared to 13 (26% of the control group, reported the scores on the Mell-Krat Scale indicative of the presence of dysfunctions in sexual reactivity (P≤0.001. Infertile women reported significantly higher levels of depressive symptoms than the women from the control group (P≤0.001. Negative correlations were observed between sexual satisfaction and dyadic functioning in both groups (P≤0.05; however, the patterns of these associations were different in infertile and fertile women. For example, negative correlations were found between satisfaction with control and task accomplishment, role performance, affective involvement, and values and norms in infertile women. However, these relationships were not observed in the control group. No correlations were revealed between sexual reactivity and dyadic functioning in infertile women and the control group. Negative correlations were observed between satisfaction with

  1. Sexual Satisfaction and Sexual Reactivity in Infertile Women: The Contribution of The Dyadic Functioning and Clinical Variables.

    Science.gov (United States)

    Czyżkowska, Anna; Awruk, Katarzyna; Janowski, Konrad

    2016-01-01

    Infertility is a factor which has been linked to higher prevalence of sexual dysfunctions in women; however, ambiguous results have been reported about the impact of infertility on women's sexual satisfaction. The purpose of this study was to compare sexual and dyadic functioning in infertile and fertile women. Furthermore, the associations between sexual variables and clinical variables (depressive symptoms, period trying to conceive, and treatment period) were assessed in infertile women sample. The cross-sectional study involved 50 women with the history of infertility and 50 fertile women recruited from the general population. The Sexual Satisfaction Scale (SSS), Mell-Krat Scale (women's version), Family Assessment Measure (FAM-III), and Beck Depression Inventory (BDI) were administered to all participants. Infertile women reported lower sexual satisfaction and more maladaptive patterns of dyadic functioning in comparison to the control group. As many as 45 (90%) of infertile women, compared to 13 (26%) of the control group, reported the scores on the Mell-Krat Scale indicative of the presence of dysfunctions in sexual reactivity (P≤0.001). Infertile women reported significantly higher levels of depressive symptoms than the women from the control group (P≤0.001). Negative correlations were observed between sexual satisfaction and dyadic functioning in both groups (P≤0.05); however, the patterns of these associations were different in infertile and fertile women. For example, negative correlations were found between satisfaction with control and task accomplishment, role performance, affective involvement, and values and norms in infertile women. However, these relationships were not observed in the control group. No correlations were revealed between sexual reactivity and dyadic functioning in infertile women and the control group. Negative correlations were observed between satisfaction with control and relationship duration and treatment period as well

  2. Catabolism of Branched Chain Amino Acids Contributes Significantly to Synthesis of Odd-Chain and Even-Chain Fatty Acids in 3T3-L1 Adipocytes.

    Directory of Open Access Journals (Sweden)

    Scott B Crown

    Full Text Available The branched chain amino acids (BCAA valine, leucine and isoleucine have been implicated in a number of diseases including obesity, insulin resistance, and type 2 diabetes mellitus, although the mechanisms are still poorly understood. Adipose tissue plays an important role in BCAA homeostasis by actively metabolizing circulating BCAA. In this work, we have investigated the link between BCAA catabolism and fatty acid synthesis in 3T3-L1 adipocytes using parallel 13C-labeling experiments, mass spectrometry and model-based isotopomer data analysis. Specifically, we performed parallel labeling experiments with four fully 13C-labeled tracers, [U-13C]valine, [U-13C]leucine, [U-13C]isoleucine and [U-13C]glutamine. We measured mass isotopomer distributions of fatty acids and intracellular metabolites by GC-MS and analyzed the data using the isotopomer spectral analysis (ISA framework. We demonstrate that 3T3-L1 adipocytes accumulate significant amounts of even chain length (C14:0, C16:0 and C18:0 and odd chain length (C15:0 and C17:0 fatty acids under standard cell culture conditions. Using a novel GC-MS method, we demonstrate that propionyl-CoA acts as the primer on fatty acid synthase for the production of odd chain fatty acids. BCAA contributed significantly to the production of all fatty acids. Leucine and isoleucine contributed at least 25% to lipogenic acetyl-CoA pool, and valine and isoleucine contributed 100% to lipogenic propionyl-CoA pool. Our results further suggest that low activity of methylmalonyl-CoA mutase and mass action kinetics of propionyl-CoA on fatty acid synthase result in high rates of odd chain fatty acid synthesis in 3T3-L1 cells. Overall, this work provides important new insights into the connection between BCAA catabolism and fatty acid synthesis in adipocytes and underscores the high capacity of adipocytes for metabolizing BCAA.

  3. Neuraminidase-1 contributes significantly to the degradation of neuronal B-series gangliosides but not to the bypass of the catabolic block in Tay–Sachs mouse models

    Directory of Open Access Journals (Sweden)

    Z.K. Timur

    2015-09-01

    Full Text Available Tay–Sachs disease is a severe lysosomal storage disorder caused by mutations in the HEXA gene coding for α subunit of lysosomal β-Hexosaminidase A enzyme, which converts GM2 to GM3 ganglioside. HexA−/− mice, depleted of the β-Hexosaminidase A iso-enzyme, remain asymptomatic up to 1 year of age because of a metabolic bypass by neuraminidase(s. These enzymes remove a sialic acid residue converting GM2 to GA2, which is further degraded by the still intact β-Hexosaminidase B iso-enzyme into lactosylceramide. A previously identified ganglioside metabolizing neuraminidase, Neu4, is abundantly expressed in the mouse brain and has activity against gangliosides like GM2 in vitro. Neu4−/− mice showed increased GD1a and decreased GM1 ganglioside in the brain suggesting the importance of the Neu4 in ganglioside catabolism. Mice with targeted disruption of both HexA and Neu4 genes showed accumulating GM2 ganglioside and epileptic seizures with 40% penetrance, indicating that the neuraminidase Neu4 is a modulatory gene, but may not be the only neuraminidase contributing to the metabolic bypass in HexA−/− mice. Therefore, we elucidated the biological role of neuraminidase-1 in ganglioside degradation in mouse. Analysis of HexA−/−Neu1−/− and HexA−/−Neu4−/−Neu1−/− mice models showed significant contribution of neuraminidase-1 on B-series ganglioside degradation in the brain. Therefore, we speculate that other neuraminidase/neuraminidases such as Neu2 and/or Neu3 might be also involved in the ganglioside degradation pathway in HexA−/− mice.

  4. Co-relation of variables as determined from panoramic radiograph and evaluating their significance in eruption of permanent mandibular third molar

    Directory of Open Access Journals (Sweden)

    Kushal Amin

    2008-01-01

    Full Text Available Purpose of the Study: Purpose of the study is to investigate whether the variables associated with the permanent mandibular third molar (PMM3 and arch dimensions could be co-related and significantly differentiated between a fully erupted and mesially impacted PMM3 among a set of Indian population. Study Design: A standardized panoramic radiograph was taken of subjects of age 21 years and above. Patients with missing tooth from mandibular arch, subjects undergoing or having history of orthodontic treatment, subjects having disto-angular, horizontal or vertical impacted PMM3 were excluded from the study. Subjects were divided into 2 groups: (1 mesially impacted PMM3 and (2 vertically erupted PMM3. Following measurements were taken from acetate paper tracing of standardized panoramic radiograph: (1 Angulation of long axis of PMM3 to permanent mandibular second molar (theta (2 Angulation of PMM 3 to base of mandible (theta 2 (3 Gonial angle (theta 3 (4 Mesio-distal width of PMM 3 (5 Retro molar space. From these measurements Ganss ratio (retro molar space /PMM3 crown width. was calculated. Results and Conclusion: Results revealed that angle theta 1, angle theta 2, retro molar space and Ganss ratio were positively co-related and highly significant variables associated with the mesially and vertically erupted teeth as measured on panoramic radiograph. Using these variables a long-term study can be carried out to predict the ultimate position of lower third molar in the arch so that if there is a probability of the tooth being impacted at a later age, a prophylactic germectomy can be performed at an early age.

  5. Contribution and significance of Heidelberg retinal tomography II in diagnostics of ocular hypertension and its conversion into primary open-angle glaucoma

    Directory of Open Access Journals (Sweden)

    Marković Vujica

    2009-01-01

    Full Text Available Background/Aim. A term 'ocular hypertension' is used when IOP is found to be > 21 mmHg on two consecutive occasions, in the absence of detectable glaucomatous damage. The aim of this study was to determine the significance and contribution of Heidelberg Retinal Tomography II (HRT II results that show very early, subtle changes in retinal neurofibre layers (RNFL in the optic nerve head that are specific for glaucoma itself (the loss of neuroretinal rim area and an increase of Cup/Disc ratio, but are not possible to register by an ophthalmoscope. Also, when the results of the functional tests remain unchanged, that confirms the conversion of ocular hypertension into glaucoma. Methods. During a 5-year study period (2002-2007, 29 patients with ocular hypertension were examined. The frequency of control examinations, based on the presence of risk factors for glaucoma development, was 3-6 months. The examination also included IOP measurements with Goldmann Applanation Tonometry (GAT, central corneal thickness (CCT determination by pachymetry, the examination of chamber angle using indirect gonioscopy, visual field tests by computerized perimetry and also papillae nervi optici (PNO examination by using HRT II. The application of HRT II enables a great number of stereometric parameters of optic disc, the most important being the rim area and Cup/Disc (C/D ratio, which was followed during the control examination by each segment, as well as PNO in global. Results. In the examination period, three cases of conversion of ocular hypertension into a primary open-angle glaucoma were found. In the group of patients with ocular hypertension, HRT II results after six months did not show a significant increase in C/D ratio. No significant loss of rim area or rim volume was found either. In three cases of conversion, HRT II results after 3 months showed an increase of C/D ratio and also a significant loss in rim volume at first examination (0.413 comparing to the

  6. Sediment contribution from coastal-cliff erosion into the Nile's littoral cell and its significance to cliff-retreat mitigation efforts

    Science.gov (United States)

    Katz, Oded; Mushkin, Amit; Crouvi, Onn; Alter, Samuel; Shemesh, Ran

    2017-04-01

    In 2013 the government of Israel initiated a national mitigation program aimed to prevent further collapse and retreat of the country's coastal cliffs, which occur along the northern termination of the Niles's littoral cell (NLC) in the eastern Mediterranean. The goals of this large-scale program are to protect infrastructure and property proximal to the cliff and to conduct long-term maintenance and monitoring of this highly dynamic and sensitive land-sea interface that spans 40 km of Israel's coast line. Here, we examine the possible impact of proposed cliff retreat mitigation efforts on long-shore sediment transport (LST) and coastal dynamics in the region. We used airborne LiDAR spanning a 9-year period between 2006 and 2015 to quantify the annual contribution of sediment eroded from a 20-km-long segment of Israel's coastal cliffs into the NLC. Our measurements reveal 282±85*103 m3 of sediment eroded from the cliff and delivered into the NLC during the studied period. Considering our study area comprises 50% of Israel's sea cliffs we infer an average contribution rate of 30,000-60,000 m^3/yr of cliff-derived sediment into the NLC prior to the planned broad-scale implementation of cliff-retreat mitigation measures. Previous studies report an average net LST flux of 80,000 - 90,000 m3 that reaches the northern termination of the NLC at Haifa Bay annually. Thus, our results suggest that Israel's actively eroding coastal cliffs are primary contributors (40-80%) to the LST budget along the northern termination of the NLC. It therefore appears that successful implementation of the coastal-cliff protection program along Israel's coastline will result in a significant sand deficit, which may drive LST in this part of the NLC out of its 'background' state. In the likely case that the energy/currents driving LST do not change, a possible outcome of this sediment deficit could be increased beach erosion along Israel's coast line to make up for the lost volumes of cliff

  7. Contribution to the characterization of 222-radon concentrations variability in water to the understanding of an aquifer behaviour in fractured medium: example of the Ploemeur site, Morbihan

    International Nuclear Information System (INIS)

    Le Druillennec, Th.

    2007-06-01

    Heterogeneous fractured aquifers which developed in crystalline rocks, such as schist or granite, supply 20% of tap water production of Brittany. These fractured media present a large range of permeability. In these aquifers, fluid flow and transport of elements dissolved in water are strongly related on the geometry of the fractured network. Increasing the knowledge of the hydrogeological behaviour of the aquifer is fundamental for the management and the protection of the groundwater resources. Radon-222 is a radioactive noble gas produced from radium-226 further to the radioactive decay of uranium-238; it occurs naturally in ground waters and derives primarily from U-rich rocks and minerals that have been in contact with water. Radon-222 concentrations in waters are liable to provide significant and relevant information on both the geometry of a fracture network and the flow distribution. Furthermore, radon may also be used as a tracer in the aquifer of water exchanges between zones of variable permeability. Three main results were obtained in this study: 1. An accurate characterisation of the radon concentrations in water was carried out in the Ploemeur aquifer (Brittany, France). These results highlight the variability in the spatial and vertical distributions of 222 Rn activity in groundwater together with a wide range of concentrations extending from 0 to 1 500 Bq.L -1 . 2. The influence of fracture aperture on radon content in groundwater has been demonstrated with the modelling of radon concentration. Indeed, the satisfactory results obtained with a simple crack model highlight that the geometry of the fracture network controls the radon activity in groundwater. 3. Thus, the results of pumping tests performed in the boreholes improved our understanding of the system. After the pumping test, an increase of the radon content in groundwater occurred and evidenced a contribution of a radon-rich water to supply the flow rate that seems to come from the low

  8. Validation of three noninvasive laboratory variables to predict significant fibrosis and cirrhosis in patients with chronic hepatitis C in Saudi Arabia

    International Nuclear Information System (INIS)

    Ado, Ayman A.; Al-Swat, Khalid; Azzam, N.; Al-Faleh, Faleh; Ahmed, S.

    2007-01-01

    We tested the clinical utility of the platelet count, aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio, and the AST to platelet ratio index (APRI) score in predicting the presence or absence of advanced fibrosis and cirrhosis in patients with chronic hepatitis C in Saudi Arabia. Liver biopsy procedures performed on chronic hepatitis C patients in our gastroenterology unit at King Khalid University Hospital were traced form records between 1998 to 2003. The hospital computer database was then accessed and detailed laboratory parameters obtained. By plotting receiver operating characteristic curves (ROC), three selected models (platelet count, AST/ALT ratio and the APRI score) were compared in terms of the best variable to predict significant fibrosis. Two hundred and forty-six patients with hepatitis C were included in this analysis. Overall, 26% of patients had advanced fibrosis. When comparing the three above mentioned prediction models, APRI score was the one associated with the highest area under the curve (AUC) = 0.812 (95%Cl, 0.756-0.868) on the ROC curves, compared to the platelet count and AST/ALT ratio, which yielded an AUC of 0.783 (0.711-0.855) and 0.716 (0.642-0.789), respectively. The APRI score seemed to be the best predictive variable for the presence or absence of advanced fibrosis in Saudi hepatitis C patients. (author)

  9. Operational Analysis of Distribution Systems Featuring Large-scale Variable RES: Contributions of Energy Storage Systems and Switchable Capacitor Banks

    OpenAIRE

    Mário Pascoal Santos Pereira

    2017-01-01

    In the last decade, the level of variable renewable energy sources (RESs) integrated in distribution network systems have been continuously growing. This adds more uncertainty to these systems, which also face many traditional sources of uncertainty, and those pertaining to other emerging technologies such as demand response and electric vehicles. As a result, distribution system operators are finding it increasingly difficult to maintain an optimal operation of such network systems. These ch...

  10. Variability of breath condensate pH may contribute to the better understanding of non-allergic seasonal respiratory diseases

    Science.gov (United States)

    Kullmann, Tamás; Szipőcs, Annamária

    2017-09-01

    The seasonal variability of certain non-allergic respiratory diseases is not clearly understood. Analysis of the breath condensate, the liquid that can be collected by breathing into a cold tube, has been proposed to bring closer to the understanding of airway pathologies. It has been assumed, that (1) airway lining fluid was a stable body liquid and (2) the breath condensate samples were representative of the airway lining fluid. Research was focussed on the identification of biomarkers indicative of respiratory pathologies. Despite 30 years of extended investigations breath condensate analysis has not gained any clinical implementation so far. The pH of the condensate is the characteristic that can be determined with the highest reproducibility. The present paper shows, that contrary to the initial assumptions, breath condensate is not a representative of the airway lining fluid, and the airway lining fluid is not a stable body liquid. Condensate pH shows baseline variability and it is influenced by drinking and by the ambient temperature. The changes in condensate pH are linked to changes in airway lining fluid pH. The variability of airway lining fluid pH may explain seasonal incidence of certain non-allergic respiratory diseases such as the catching of a common cold and the increased incidence of COPD exacerbations and exercise-induced bronchoconstriction in cold periods.

  11. Factors that contribute to physician variability in decisions to limit life support in the ICU: a qualitative study.

    Science.gov (United States)

    Wilson, Michael E; Rhudy, Lori M; Ballinger, Beth A; Tescher, Ann N; Pickering, Brian W; Gajic, Ognjen

    2013-06-01

    Our aim was to explore reasons for physician variability in decisions to limit life support in the intensive care unit (ICU) utilizing qualitative methodology. Single center study consisting of semi-structured interviews with experienced physicians and nurses. Seventeen intensivists from medical (n = 7), surgical (n = 5), and anesthesia (n = 5) critical care backgrounds, and ten nurses from medical (n = 5) and surgical (n = 5) ICU backgrounds were interviewed. Principles of grounded theory were used to analyze the interview transcripts. Eleven factors within four categories were identified that influenced physician variability in decisions to limit life support: (1) physician work environment-workload and competing priorities, shift changes and handoffs, and incorporation of nursing input; (2) physician experiences-of unexpected patient survival, and of limiting life support in physician's family; (3) physician attitudes-investment in a good surgical outcome, specialty perspective, values and beliefs; and (4) physician relationship with patient and family-hearing the patient's wishes firsthand, engagement in family communication, and family negotiation. We identified several factors which physicians and nurses perceived were important sources of physician variability in decisions to limit life support. Ways to raise awareness and ameliorate the potentially adverse effects of factors such as workload, competing priorities, shift changes, and handoffs should be explored. Exposing intensivists to long term patient outcomes, formalizing nursing input, providing additional training, and emphasizing firsthand knowledge of patient wishes may improve decision making.

  12. Quantifying the Relative Contributions of Forest Change and Climatic Variability to Hydrology in Large Watersheds: A Critical Review of Research Methods

    Directory of Open Access Journals (Sweden)

    Xiaohua Wei

    2013-06-01

    Full Text Available Forest change and climatic variability are two major drivers for influencing change in watershed hydrology in forest–dominated watersheds. Quantifying their relative contributions is important to fully understand their individual effects. This review paper summarizes the progress on quantifying the relative contributions of forest or land cover change and climatic variability to hydrology in large watersheds using available case studies. It compared pros and cons of various research methods, identified research challenges and proposed future research priorities. Our synthesis shows that the relative hydrological effects of forest changes and climatic variability are largely dependent on their own change magnitudes and watershed characteristics. In some severely disturbed watersheds, impacts of forest changes or land use changes can be as important as those from climatic variability. This paper provides a brief review on eight selected research methods for this type of research. Because each method or technique has its own strengths and weaknesses, combining two or more methods is a more robust approach than using any single method alone. Future research priorities include conducting more case studies, refining research methods, and considering mechanism-based research using landscape ecology and geochemistry approaches.

  13. Language and communication skills in preschool children with autism spectrum disorders: contribution of cognition, severity of autism symptoms, and adaptive functioning to the variability.

    Science.gov (United States)

    Kjellmer, Liselotte; Hedvall, Åsa; Fernell, Elisabeth; Gillberg, Christopher; Norrelgen, Fritjof

    2012-01-01

    This study examined the contribution of cognitive function, severity of autism, and adaptive functioning to the variability in language and communication skills in 129 preschool children (aged 24-63 months) with autism spectrum disorder (ASD). Participants were selected from a representative research cohort of 208 preschool children on the basis of caregiver completion of the MacArthur-Bates Communicative Development Inventories (CDI). The children were classified into three cognitive groups: (a) Normal intelligence; (b) Developmental delay; and (c) Intellectual disability. Autism symptom severity was measured by the Autistic Behavior Checklist (ABC), and adaptive functioning by the Daily Living Skills (DLS) and Socialization (Soc) subscales from the Vineland Adaptive Behavior Scales. For each of five CDI variables (Phrases understood, Words understood, Words produced, Gestures and actions, and Language use), the contribution of cognition, severity of autism symptoms, and adaptive functioning to the variability was examined. Cognition and age explained about half or more of the variance in the four verbal language CDI variables, but only about one fourth of the variance in the non-verbal communication variable Gestures and actions. Severity of autism symptoms and the two adaptive measures (DLS and Soc) each only accounted for a few percent more of the variance in the four CDI language variables; however, for Gestures and actions, an additional 11-21% of the variance was accounted for. In conclusion, for children with ASD, receptive and expressive language is mainly related to cognitive level, whereas non-verbal communication skills seem to also be related to severity of autism symptoms and adaptive functioning. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Contribution to the dynamic analysis of prestressed and preloaded spring-mass systems of variable structure under shock load

    International Nuclear Information System (INIS)

    Matthees, W.

    1980-01-01

    The purpose of this work is the development of a method to analyze on impact load structural systems whose topologically variable system arrangements are dependent on temporarily varying deformation conditions impact loads. This method serves to examine the prototype of a dynamically excited burst protection system for a nuclear power plant. Evidence is given that in case of hypothetical failure of the prestressed reactor pressure vessel the maximum load capacity of the reactor core is not exceeded, which in turn guarantees safe shutdown of the reactor. (orig./HP) [de

  15. Relative Contributions of Mean-State Shifts and ENSO-Driven Variability to Precipitation Changes in a Warming Climate*

    Energy Technology Data Exchange (ETDEWEB)

    Bonfils, Céline J. W.; Santer, Benjamin D.; Phillips, Thomas J.; Marvel, Kate; Leung, L. Ruby; Doutriaux, Charles; Capotondi, Antonietta

    2015-12-01

    The El Niño-Southern Oscillation (ENSO) is an important driver of regional hydroclimate variability through far-reaching teleconnections. Most climate models project an increase in the frequency of extreme El Niño events under increased greenhouse-gas (GHG) forcing. However, it is unclear how other aspects of ENSO and ENSO-driven teleconnections will evolve in the future. Here, we identify in 20th century sea-surface temperature (SST) observations a time-invariant ENSO-like (ENSOL) pattern that is largely uncontaminated by GHG forcing. We use this pattern to investigate the future precipitation (P) response to ENSO-like SST anomalies. Models that better capture observed ENSOL characteristics produce P teleconnection patterns that are in better accord with observations and more stationary in the 21st century. We decompose the future P response to ENSOL into the sum of three terms: (1) the change in P mean state, (2) the historical P response to ENSOL, and (3) a future enhancement in the P response to ENSOL. In many regions, this last term can aggravate the P extremes associated with ENSO variability. This simple decomposition allows us to identify regions likely to experience ENSOL-induced P changes that are without precedent in the current climate.

  16. The Epidemiological Significance and Temporal Stability of Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats-Based Method Applied to Mycobacterium tuberculosis in China

    Directory of Open Access Journals (Sweden)

    Yang Li

    2018-04-01

    Full Text Available This study aimed to validate the epidemiological significance and temporal stability of Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR typing in a genetically and geographically diverse set of clinical isolates from patients diagnosed with pulmonary tuberculosis in China. Between 2010 and 2013, a total of 982 Mycobacterium tuberculosis isolates were collected from four population-based investigations in China. Apart from the currently applied 24-locus MIRU-VNTR, six additional hypervariable loci were analyzed in order to validate the MIRU-VNTR combinations in terms of their epidemiological links, clustering time span, and paired geographic distance. In vitro temporal stability was analyzed for both individual MIRU-VNTR loci, and for several combinations of loci. In the present study, four MIRU-VNTR combinations, including the hypervariable loci 3820, 3232, 2163a, and 4120, were evaluated. All of these combinations obtained a Hunter-Gaston discriminatory index (HGDI value over 0.9900 with a reduced clustering proportion (from 32.0% to 25.6%. By comparing epidemiological links, clustering time span, and paired geographic distance, we found that the performances of the four MIRU-VNTR combinations were comparable to the insertion sequence 6110 restriction fragment length polymorphism (IS6110-RFLP, and significantly better than that of 24-locus MIRU-VNTR genotyping alone. The proportion of temporally stable loci ranged from 90.5% to 92.5% within the combined MIRU-VNTR genotyping, which is higher than IS6110-RFLP (85.4%. By adding four hypervariable loci to the standard 24-locus MIRU-VNTR genotyping, we obtained a high discriminatory power, stability and epidemiological significance. This algorithm could therefore be used to improve tuberculosis transmission surveillance and outbreak investigation in China.

  17. General and Specific Contributions of RAN to Reading and Arithmetic Fluency in First Graders: A Longitudinal Latent Variable Approach.

    Science.gov (United States)

    Hornung, Caroline; Martin, Romain; Fayol, Michel

    2017-01-01

    In the present study, we opted for a longitudinal design and examined rapid automatized naming (RAN) performance from two perspectives. In a first step, we examined the structure of RAN performance from a general cognitive perspective. We investigated whether rapid naming measures (e.g., digit RAN and color RAN) reflect a mainly domain-general factor or domain-specific factors. In a second step, we examined how the best fitting RAN model was related to reading and arithmetic outcomes, assessed several months later. Finally in a third step we took a clinical perspective and investigated specific contributions of RAN measures to reading and arithmetic outcomes. While RAN has emerged as a promising predictor of reading, the relationship between RAN and arithmetic has been less examined in the past. Hundred and twenty-two first graders completed seven RAN tasks, each comprising visually familiar stimuli such as digits, vowels, consonants, dice, finger-numeral configurations, objects, and colors. Four months later the same children completed a range of reading and arithmetic tasks. From a general descriptive perspective, structural equation modeling supports a one-dimensional RAN factor in 6- to -7-year-old children. However, from a clinical perspective, our findings emphasize the specific contributions of RANs. Interestingly, alphanumeric RANs (i.e., vowel RAN) were most promising when predicting reading skills and number-specific RANs (i.e., finger-numeral configuration RAN) were most promising when predicting arithmetic fluency. The implications for clinical and educational practices will be discussed.

  18. Contribution to the application of the random vibration theory to the seismic analysis of structures via state variables

    International Nuclear Information System (INIS)

    Maestrini, A.P.

    1979-04-01

    Several problems related to the application of the theory of random by means of state variables are studied. The well-known equations that define the propagation of the mean and the variance for linear and non-linear systems are first presented. The Monte Carlo method is next resorted to in order to determine the applicability of the hypothesis of a normally distributed output in case of linear systems subjected to non-Gaussian excitations. Finally, attention is focused on the properties of linear filters and modulation functions proposed to simulate seismic excitations as non stationary random processes. Acceleration spectra obtained by multiplying rms spectra by a constant factor are compared with design spectra suggested by several authors for various soil conditions. In every case, filter properties are given. (Author) [pt

  19. Manual blood exchange transfusion does not significantly contribute to parasite clearance in artesunate-treated individuals with imported severe Plasmodium falciparum malaria

    NARCIS (Netherlands)

    Kreeftmeijer-Vegter, Annemarie R.; Melo, Mariana de Mendonça; de Vries, Peter J.; Koelewijn, Rob; van Hellemond, Jaap J.; van Genderen, Perry J. J.

    2013-01-01

    Exchange transfusion (ET) has remained a controversial adjunct therapy for the treatment of severe malaria. In order to assess the relative contribution of ET to parasite clearance in severe malaria, all patients receiving ET as an adjunct treatment to parenteral quinine or to artesunate were

  20. Manual blood exchange transfusion does not significantly contribute to parasite clearance in artesunate-treated individuals with imported severe Plasmodium falciparum malaria

    NARCIS (Netherlands)

    A.R. Kreeftmeijer-Vegter (Annemarie); M.M. de Melo (Mariana ); P.J. de Vries (Peter); R. Koelewijn (Rob); J.J. van Hellemond (Jaap); P.J.J. van Genderen (Perry)

    2013-01-01

    textabstractBackground: Exchange transfusion (ET) has remained a controversial adjunct therapy for the treatment of severe malaria. In order to assess the relative contribution of ET to parasite clearance in severe malaria, all patients receiving ET as an adjunct treatment to parenteral quinine or

  1. General and Specific Contributions of RAN to Reading and Arithmetic Fluency in First Graders: A Longitudinal Latent Variable Approach

    Directory of Open Access Journals (Sweden)

    Caroline Hornung

    2017-10-01

    Full Text Available In the present study, we opted for a longitudinal design and examined rapid automatized naming (RAN performance from two perspectives. In a first step, we examined the structure of RAN performance from a general cognitive perspective. We investigated whether rapid naming measures (e.g., digit RAN and color RAN reflect a mainly domain-general factor or domain-specific factors. In a second step, we examined how the best fitting RAN model was related to reading and arithmetic outcomes, assessed several months later. Finally in a third step we took a clinical perspective and investigated specific contributions of RAN measures to reading and arithmetic outcomes. While RAN has emerged as a promising predictor of reading, the relationship between RAN and arithmetic has been less examined in the past. Hundred and twenty-two first graders completed seven RAN tasks, each comprising visually familiar stimuli such as digits, vowels, consonants, dice, finger-numeral configurations, objects, and colors. Four months later the same children completed a range of reading and arithmetic tasks. From a general descriptive perspective, structural equation modeling supports a one-dimensional RAN factor in 6- to -7-year-old children. However, from a clinical perspective, our findings emphasize the specific contributions of RANs. Interestingly, alphanumeric RANs (i.e., vowel RAN were most promising when predicting reading skills and number-specific RANs (i.e., finger-numeral configuration RAN were most promising when predicting arithmetic fluency. The implications for clinical and educational practices will be discussed.

  2. Clinical significance of power spectral analysis of heart rate variability and {sup 123}I-metaiodobenzylguanidine (MIBG) myocardial imaging for assessing the severity of heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Yoshio; Fukuoka, Shuji; Shimotsu, Yoriko; Sasaki, Tatsuya; Kamakura, Shiro; Yasumura, Yoshio; Miyatake, Kunio; Shimomura, Katsuro [National Cardiovascular Center, Suita, Osaka (Japan); Tani, Akihiro

    1997-04-01

    The significance of power spectral analysis of heart rate variability and of MIBG myocardial imaging to see the sympathetic nervous function was evaluated in patients with congestive heart failure due to dilated cardiomyopathy. Subjects were 10 normal volunteers and 8 patients with severity NYHA II; 10 normals and 25 patients with NYHA II and III; and 17 patients treated with a beta-blocker (metoprolol 5-40 mg). ECG was recorded with a portable ECG recorder for measuring RR intervals for 24 hr, which were applied for power spectral analysis. Early and delayed imagings with 111 MBq of {sup 123}I-MIBG were performed at 15 min and 4 hr, respectively, after its intravenous administration for acquisition of anterior planar and SPECT images. Myocardial blood flow SPECT was also done with 111 MBq of {sup 201}Tl given intravenously, and difference of total defect scores between MIBG and Tl images was computed. MIBG myocardial sympathetic nerve imaging in those patients was found useful to assess the severity of heart failure, to predict the risk patients for beta-blocker treatment and to assess the risk in complicated ventricular tachycardia. (K.H.)

  3. Water use by terrestrial ecosystems: temporal variability in rainforest and agricultural contributions to evapotranspiration in Mato Grosso, Brazil

    International Nuclear Information System (INIS)

    Lathuillière, Michael J; Johnson, Mark S; Donner, Simon D

    2012-01-01

    The state of Mato Grosso, Brazil, has experienced rapid land use changes from the expansion of rain-fed agriculture (primarily soybean and pasture). This study presents changes to evapotranspiration contributions from terrestrial ecosystems in Mato Grosso over the 2000–9 period. Instead of focusing on land use change to infer hydrologic change, in this paper we assess hydrologic changes using remote sensing, meteorological and agricultural production data to determine the rainforest, crop and pasture components of total evapotranspiration. Humid tropical rainforest evapotranspiration represented half of the state’s total evapotranspiration in 2000 despite occupying only 40% of the total land area. Annual evapotranspiration fluxes from rainforest declined at a rate of 16.2 km 3 y −1 (R 2 = 0.82, p-value < 0.01) as a result of deforestation between 2000 and 2009, representing a 25% decline in rainforest evapotranspiration since 2000. By 2009, rainforest cover accounted for only 40% of total evapotranspiration. Over the same period, crop evapotranspiration doubled, but this increase was offset by a decline in pasture evapotranspiration. Pasture fluxes were at least five times larger than crop evapotranspiration fluxes in 2000–9, with increases spatially focused at the agricultural frontier. The results highlight the expanding appropriation of soil moisture stocks for use in Mato Grosso’s rain-fed agroecosystems. (letter)

  4. The relative contribution of processes driving variability in flow, shear, and turbidity over a fringing coral reef: West Maui, Hawaii

    Science.gov (United States)

    Storlazzi, C.D.; Jaffe, B.E.

    2008-01-01

    High-frequency measurements of waves, currents and water column properties were made on a fringing coral reef off northwest Maui, Hawaii, for 15 months between 2001 and 2003 to aid in understanding the processes governing flow and turbidity over a range of time scales and their contributions to annual budgets. The summer months were characterized by consistent trade winds and small waves, and under these conditions high-frequency internal bores were commonly observed, there was little net flow or turbidity over the fore reef, and over the reef flat net flow was downwind and turbidity was high. When the trade winds waned or the wind direction deviated from the dominant trade wind orientation, strong alongshore flows occurred into the typically dominant wind direction and lower turbidity was observed across the reef. During the winter, when large storm waves impacted the study area, strong offshore flows and high turbidity occurred on the reef flat and over the fore reef. Over the course of a year, trade wind conditions resulted in the greatest net transport of turbid water due to relatively strong currents, moderate overall turbidity, and their frequent occurrence. Throughout the period of study, near-surface current directions over the fore reef varied on average by more than 41?? from those near the seafloor, and the orientation of the currents over the reef flat differed on average by more than 65?? from those observed over the fore reef. This shear occurred over relatively short vertical (order of meters) and horizontal (order of hundreds of meters) scales, causing material distributed throughout the water column, including the particles in suspension causing the turbidity (e.g. sediment or larvae) and/or dissolved nutrients and contaminants, to be transported in different directions under constant oceanographic and meteorologic forcing.

  5. Variability of extragalactic sources: its contribution to the link between ICRF and the future Gaia Celestial Reference Frame

    Science.gov (United States)

    Taris, F.; Damljanovic, G.; Andrei, A.; Souchay, J.; Klotz, A.; Vachier, F.

    2018-03-01

    Context. The first release of the Gaia catalog is available since 14 September 2016. It is a first step in the realization of the future Gaia reference frame. This reference frame will be materialized by the optical positions of the sources and will be compared with and linked to the International Celestial Reference Frame, materialized by the radio position of extragalactic sources. Aim. As in the radio domain, it can be reasonably postulated that quasar optical flux variations can alert us to potential changes in the source structure. These changes could have important implications for the position of the target photocenters (together with the evolution in time of these centers) and in parallel have consequences for the link of the reference systems. Methods: A set of nine optical telescopes was used to monitor the magnitude variations, often at the same time as Gaia, thanks to the Gaia Observation Forecast Tool. The Allan variances, which are statistical tools widely used in the atomic time and frequency community, are introduced. Results: This work describes the magnitude variations of 47 targets that are suitable for the link between reference systems. We also report on some implications for the Gaia catalog. For 95% of the observed targets, new information about their variability is reported. In the case of some targets that are well observed by the TAROT telescopes, the Allan time variance shows that the longest averaging period of the magnitudes is in the range 20-70 d. The observation period by Gaia for a single target largely exceeds these values, which might be a problem when the magnitude variations exhibit flicker or random walk noises. Preliminary computations show that if the coordinates of the targets studied in this paper were affected by a white-phase noise with a formal uncertainty of about 1 mas (due to astrophysical processes that are put in evidence by the magnitude variations of the sources), it would affect the precision of the link at the

  6. SRSF1-3 contributes to diversification of the immunoglobulin variable region gene by promoting accumulation of AID in the nucleus

    OpenAIRE

    Kawaguchi, Yuka; Nariki, Hiroaki; Kawamoto, Naoko; Kanehiro, Yuichi; Miyazaki, Satoshi; Suzuki, Mari; Magari, Masaki; Tokumitsu, Hiroshi; Kanayama, Naoki

    2017-01-01

     Activation-induced cytidine deaminase (AID) is essential for diversification of the Ig variable region (IgV). AID is excluded from the nucleus, where it normally functions. However, the molecular mechanisms responsible for regulating AID localization remain to be elucidated. The SR-protein splicing factor SRSF1 is a nucleocytoplasmic shuttling protein, a splicing isoform of which called SRSF1-3, has previously been shown to contribute to IgV diversification in chicken DT40 cells. In this stu...

  7. Dermal Exposure to Jet Fuel JP-8 Significantly Contributes to the Production of Urinary Naphthols in Fuel-Cell Maintenance Workers

    OpenAIRE

    Chao, Yi-Chun E.; Kupper, Lawrence L.; Serdar, Berrin; Egeghy, Peter P.; Rappaport, Stephen M.; Nylander-French, Leena A.

    2005-01-01

    Jet propulsion fuel 8 (JP-8) is the major jet fuel used worldwide and has been recognized as a major source of chemical exposure, both inhalation and dermal, for fuel-cell maintenance workers. We investigated the contributions of dermal and inhalation exposure to JP-8 to the total body dose of U.S. Air Force fuel-cell maintenance workers using naphthalene as a surrogate for JP-8 exposure. Dermal, breathing zone, and exhaled breath measurements of naphthalene were obtained using tape-strip sam...

  8. Variability of the Cyclin-Dependent Kinase 2 Flexibility Without Significant Change in the Initial Conformation of the Protein or Its Environment; a Computational Study.

    Science.gov (United States)

    Taghizadeh, Mohammad; Goliaei, Bahram; Madadkar-Sobhani, Armin

    2016-06-01

    Protein flexibility, which has been referred as a dynamic behavior has various roles in proteins' functions. Furthermore, for some developed tools in bioinformatics, such as protein-protein docking software, considering the protein flexibility, causes a higher degree of accuracy. Through undertaking the present work, we have accomplished the quantification plus analysis of the variations in the human Cyclin Dependent Kinase 2 (hCDK2) protein flexibility without affecting a significant change in its initial environment or the protein per se. The main goal of the present research was to calculate variations in the flexibility for each residue of the hCDK2, analysis of their flexibility variations through clustering, and to investigate the functional aspects of the residues with high flexibility variations. Using Gromacs package (version 4.5.4), three independent molecular dynamics (MD) simulations of the hCDK2 protein (PDB ID: 1HCL) was accomplished with no significant changes in their initial environments, structures, or conformations, followed by Root Mean Square Fluctuations (RMSF) calculation of these MD trajectories. The amount of variations in these three curves of RMSF was calculated using two formulas. More than 50% of the variation in the flexibility (the distance between the maximum and the minimum amount of the RMSF) was found at the region of Val-154. As well, there are other major flexibility fluctuations in other residues. These residues were mostly positioned in the vicinity of the functional residues. The subsequent works were done, as followed by clustering all hCDK2 residues into four groups considering the amount of their variability with respect to flexibility and their position in the RMSF curves. This work has introduced a new class of flexibility aspect of the proteins' residues. It could also help designing and engineering proteins, with introducing a new dynamic aspect of hCDK2, and accordingly, for the other similar globular proteins. In

  9. Significance of out-of-plane electronic contributions in Bi-cuprates studied by resonant photoelectron spectroscopy at the Cu2p edge

    Science.gov (United States)

    Janowitz, Christoph; Schmeißer, Dieter

    2018-04-01

    In high-temperature superconductors with a layered crystal structure, the copper-oxygen planes are commonly considered to dominate the electronic properties around the Fermi energy. As a consequence, out-of-plane contributions are often neglected in the description of these materials. Here we report on a resonant photoemission study of Pb0,4Bi1,6Sr2,0CaCu2O8 ((Pb, Bi)-2212) and Pb0,6Bi1,4Sr1.5La0.5CuO6 ((Pb, Bi)-2201)) single crystals to unravel the resonant decay mechanisms at the Cu2p absorption edge. We find evidence for a pronounced polarization dependence caused by two different Auger processes for in-plane and out-of-plane orientations. We deduce that the lowest energy valence state—which is involved in the two Auger processes—consists of three-dimensional contributions by admixed out-of-plane Sr, Bi, and O2p states. It also suggests that the doping-induced charge density is dynamic, fluctuating within the Cu-O plane, and spills out perpendicular to it. This suggests that out-of-plane electronic degrees of freedom should be included in future consistent theoretical models of these materials.

  10. The contribution of personal and seniority variables to the presence of stress symptoms among Israeli UAV operators.

    Science.gov (United States)

    Gal, Shiri; Shelef, Leah; Oz, Idit; Yavnai, Nirit; Carmon, Erez; Gordon, Shirley

    2016-01-01

    The exposure to war scenes via screens, despite offering a degree of detachment, can be stressful for the operator. The aim of the current study is to examine the existence of anxiety, depression, and post traumatic stress disorder (PTSD) symptoms among unmanned aerial vehicle (UAV) Israeli operators. Participants comprised 41 UAV operators (87.2% male), aged 22-38 ( M age  = 26.05, SD  = 3.54). Most (78.0%) reported having viewed battlefield scenes. All participants completed a total of five questionnaires: Beck Depression Inventory, State-Trait Anxiety Inventory, and three questionnaires of PTSD: Post Trauma Questionnaire (CAPS), the Post-Traumatic Cognition Inventory (CTPI), and the Post-Traumatic Symptom Scale (PSS). Mean scores of depression and anxiety were found significantly lower than diagnosis cut-off points ( p  UAV operators are highly beneficial for preventing psychopathology.

  11. Significant contribution of the 3′→5′ exonuclease activity to the high fidelity of nucleotide incorporation catalyzed by human DNA polymerase ϵ

    Science.gov (United States)

    Zahurancik, Walter J.; Klein, Seth J.; Suo, Zucai

    2014-01-01

    Most eukaryotic DNA replication is performed by A- and B-family DNA polymerases which possess a faithful polymerase activity that preferentially incorporates correct over incorrect nucleotides. Additionally, many replicative polymerases have an efficient 3′→5′ exonuclease activity that excises misincorporated nucleotides. Together, these activities contribute to overall low polymerase error frequency (one error per 106–108 incorporations) and support faithful eukaryotic genome replication. Eukaryotic DNA polymerase ϵ (Polϵ) is one of three main replicative DNA polymerases for nuclear genomic replication and is responsible for leading strand synthesis. Here, we employed pre-steady-state kinetic methods and determined the overall fidelity of human Polϵ (hPolϵ) by measuring the individual contributions of its polymerase and 3′→5′ exonuclease activities. The polymerase activity of hPolϵ has a high base substitution fidelity (10−4–10−7) resulting from large decreases in both nucleotide incorporation rate constants and ground-state binding affinities for incorrect relative to correct nucleotides. The 3′→5′ exonuclease activity of hPolϵ further enhances polymerization fidelity by an unprecedented 3.5 × 102 to 1.2 × 104-fold. The resulting overall fidelity of hPolϵ (10−6–10−11) justifies hPolϵ to be a primary enzyme to replicate human nuclear genome (0.1–1.0 error per round). Consistently, somatic mutations in hPolϵ, which decrease its exonuclease activity, are connected with mutator phenotypes and cancer formation. PMID:25414327

  12. U.S. contribution of section A.3. The significance of long-term supply and energy sufficiency prospects offered by fast breeders

    International Nuclear Information System (INIS)

    1978-10-01

    Costs involved in breeder deployment are identified and analyzed, i.e., high breeder capital costs, fuel cycle costs, research and development costs and discount rates. It is pointed out that while there are potential benefits to be derived from future application of fast breeders, there are also significant costs and other factors requiring consideration. Careful country-specific analyses are needed. Such analyses may conclude for example that although breeders could become economical in less highly industrialized nations, such nations may find it more economical and practical to purchase reprocessing services from existing large commercial size plants rather than deploy their own small scale reprocessing plants

  13. Contribution of the ELFG test in algorithms of non-invasive markers towards the diagnosis of significant fibrosis in chronic hepatitis C.

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Zarski

    Full Text Available BACKGROUND AND AIMS: We aimed to determine the best algorithms for the diagnosis of significant fibrosis in chronic hepatitis C (CHC patients using all available parameters and tests. PATIENTS AND METHODS: We used the database from our study of 507 patients with histologically proven CHC in which fibrosis was evaluated by liver biopsy (Metavir and tests: Fibrometer®, Fibrotest®, Hepascore®, Apri, ELFG, MP3, Forn's, hyaluronic acid, tissue inhibitor of metalloproteinase-1 (TIMP1, MMP1, collagen IV and when possible Fibroscan™. For the first test we used 90% negative predictive value to exclude patients with F≤1, next an induction algorithm was applied giving the best tests with at least 80% positive predictive value for the diagnosis of F≥2. The algorithms were computed using the R Software C4.5 program to select the best tests and cut-offs. The algorithm was automatically induced without premises on the part of the investigators. We also examined the inter-observer variations after independent review of liver biopsies by two pathologists. A medico-economic analysis compared the screening strategies with liver biopsy. RESULTS: In "intention to diagnose" the best algorithms for F≥2 were Fibrometer ®, Fibrotest®, or Hepascore® in first intention with the ELFG score in second intention for indeterminate cases. The percentage of avoided biopsies varied between 50% (Fibrotest® or Fibrometer®+ELFG and 51% (Hepascore®+ELFG. In "per-analysis" Fibroscan™+ELFG avoided liver biopsy in 55% of cases. The diagnostic performance of these screening strategies was statistically superior to the usual combinations (Fibrometer® or Fibrotest®+Fibroscan™ and was cost effective. We note that the consensual review of liver biopsies between the two pathologists was mainly in favor of F1 (64-69%. CONCLUSION: The ELFG test could replace Fibroscan in most currently used algorithms for the diagnosis of significant fibrosis including for those patients

  14. Variables process effect in the pure ferritic metal contribution deposited with an tubular metal-cored E111T5-K3 wire

    International Nuclear Information System (INIS)

    Svoboda, Hernan G; Ramini de Rissone, N.M; Surian, E; De Vedia, L

    2004-01-01

    The welding deposit performed with an ANSI-AWS E111T5-K3 type from the system C-Mn-Ni-Mo metal coring tubular welding, with a low slag generation was studied. Different operatives configurations with two thermal contribution levels (1 kJ and 1.5 kJ) and two types of protector gases (CO 2 and Ar-20%CO 2 ) at two welding position (under hand and ascendant vertical) were analyzed. The resulting pure contributor metal from the different process configurations was chemical, mechanically and structural characterized and the effect of the different process conditions was evaluated. The microstructure is fundamentally composed by FS(NA) and AF. For similar values of hardness and strength, good values of tenacity were observed and they show little variation with the process variables studied (AG)

  15. Defining Essential Biodiversity Variables (EBVs) as a contribution to Essential Ocean Variables (EOVs): A Core Task of the Marine Biodiversity Observation Network (MBON) to Accelerate Integration of Biological Observations in the Global Ocean Observing System (GOOS)

    Science.gov (United States)

    Pearlman, J.; Muller-Karger, F. E.; Sousa Pinto, I.; Costello, M. J.; Duffy, J. E.; Appeltans, W.; Fischer, A. S.; Canonico, G.; Klein, E.; Obura, D.; Montes, E.; Miloslavich, P.; Howard, M.

    2017-12-01

    The Marine Biodiversity Observation Network (MBON) is a networking effort under the umbrella of the Group on Earth Observations Biodiversity Observation Network (GEO BON). The objective of the MBON is to link existing groups engaged in ocean observation and help define practical indices to deploy in an operational manner to track changes in the number of marine species, the abundance and biomass of marine organisms, the diverse interactions between organisms and the environment, and the variability and change of specific habitats of interest. MBON serves as the biodiversity arm of Blue Planet, the initiative of the Group on Earth Observations (GEO) for the benefit of society. The Global Ocean Observing System (GOOS) was established under the auspices of the Intergovernmental Oceanographic Commission (IOC) in 1991 to organize international ocean observing efforts. The mission of the GOOS is to support monitoring to improve the management of marine and coastal ecosystems and resources, and to enable scientific research. GOOS is engaged in a continuing, rigorous process of identifying Essential Ocean Variables (EOVs). MBON is working with GOOS and the Ocean Biogeographic Information System (OBIS, also under the IOC) to define Essential Biodiversity Variables (EBVs) as those Essential Ocean Variables (EOVs) that have explicit taxonomic records associated with them. For practical purposes, EBVs are a subset of the EOVs. The focus is to promote the integration of biological EOVs including EBVs into the existing and planned national and international ocean observing systems. The definition avoids a proliferation of 'essential' variables across multiple organizations. MBON will continue to advance practical and wide use of EBVs and related EOV. This is an effective way to contribute to several UN assessments (e.g., from IPBES, IPCC, and the World Ocean Assessment under the UN Regular Process), UN Sustainable Development Goals, and to address targets and goals defined under

  16. Analysing temporal variability of particulate matter and possible contributing factors over Mahabaleshwar, a high-altitude station in Western Ghats, India

    Science.gov (United States)

    Leena, P. P.; Vijayakumar, K.; Anilkumar, V.; Pandithurai, G.

    2017-11-01

    Airborne particulate matter (PM) plays a vital role on climate change as well as human health. In the present study, temporal variability associated with mass concentrations of PM10, PM2.5, and PM1.0 were analysed using ground observations from Mahabaleswar (1348 m AMSL, 17.56 0N, 73.4 0E), a high-altitude station in the Western Ghats, India from June 2012 to May 2013. Concentrations of PM10, PM2.5, and PM1.0 showed strong diurnal, monthly, seasonal and weekday-weekend trends. The seasonal variation of PM1.0 and PM2.5 has showed highest concentrations during winter season compared to monsoon and pre-monsoon, but in the case of PM10 it showed highest concentrations in pre-monsoon season. Similarly, slightly higher PM concentrations were observed during weekends compared to weekdays. In addition, possible contributing factors to this temporal variability has been analysed based on the variation of secondary pollutants such as NO2, SO2, CO and O3 and long range transport of dust.

  17. Polymorphisms in CYP1A1 and CYP3A5 Genes Contribute to the Variability in Granisetron Clearance and Exposure in Pregnant Women with Nausea and Vomiting.

    Science.gov (United States)

    Bustos, Martha L; Zhao, Yang; Chen, Huijun; Caritis, Steve N; Venkataramanan, Raman

    2016-12-01

    Nausea and vomiting affect up to 90% of pregnant women. Granisetron is a potent and highly selective serotonin receptor antagonist and is an effective antiemetic. Findings from a prior study in pregnant women demonstrated a large interindividual variability in granisetron exposure. Granisetron is primarily metabolized by the cytochrome P450 (CYP) enzymes CYP1A1 and CYP3A and is likely a substrate of the ABCB1 transporter. Single-nucleotide polymorphisms (SNPs) in CYP3A, CYP1A1, and ABCB1 can alter drug metabolism. This study evaluated the influence of polymorphisms in CYP3A4, CYP3A5, CYP1A1, and ABCB1 on the pharmacokinetic properties of granisetron in pregnant women. The study enrolled 16 pregnant women (gestational age of 12-19 wks). All patients had nausea and vomiting and were treated with granisetron 1 mg. Granisetron plasma concentrations were determined using liquid chromatography tandem-mass spectrometry. The patients' genotype was determined using TaqMan SNP Genotyping Assays. The Hardy-Weinberg equilibrium was assessed by comparing observed and expected genotype frequencies, using the exact test. Intravenous granisetron clearance was used as the dependent variable for analysis of associations. Of 16 patients, 25% were homozygous for the allele variant CYP3A5*3 and had a significantly lower granisetron clearance and increased area under the plasma concentration-versus-time curve (AUC) compared with nonhomozygous patients. Approximately one-third of patients (n=5) were carriers for the allele variant CYP1A1*2A and had a significantly higher granisetron clearance and decreased AUC. We did not find significant differences in the AUC or clearance for any SNPs in CYP3A4 and ABCB1 genes. Polymorphisms in CYP3A5 and CYP1A1 account for some of the variability in systemic clearance and exposure of granisetron in pregnant women. © 2016 Pharmacotherapy Publications, Inc.

  18. How to regress and predict in a Bland-Altman plot? Review and contribution based on tolerance intervals and correlated-errors-in-variables models.

    Science.gov (United States)

    Francq, Bernard G; Govaerts, Bernadette

    2016-06-30

    Two main methodologies for assessing equivalence in method-comparison studies are presented separately in the literature. The first one is the well-known and widely applied Bland-Altman approach with its agreement intervals, where two methods are considered interchangeable if their differences are not clinically significant. The second approach is based on errors-in-variables regression in a classical (X,Y) plot and focuses on confidence intervals, whereby two methods are considered equivalent when providing similar measures notwithstanding the random measurement errors. This paper reconciles these two methodologies and shows their similarities and differences using both real data and simulations. A new consistent correlated-errors-in-variables regression is introduced as the errors are shown to be correlated in the Bland-Altman plot. Indeed, the coverage probabilities collapse and the biases soar when this correlation is ignored. Novel tolerance intervals are compared with agreement intervals with or without replicated data, and novel predictive intervals are introduced to predict a single measure in an (X,Y) plot or in a Bland-Atman plot with excellent coverage probabilities. We conclude that the (correlated)-errors-in-variables regressions should not be avoided in method comparison studies, although the Bland-Altman approach is usually applied to avert their complexity. We argue that tolerance or predictive intervals are better alternatives than agreement intervals, and we provide guidelines for practitioners regarding method comparison studies. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. Variable temperature ion trap studies of CH4+ + H2, HD and D2: negative temperature dependence and significant isotope effect

    International Nuclear Information System (INIS)

    Asvany, O.; Savic, I.; Schlemmer, S.; Gerlich, D.

    2004-01-01

    Reactions of methane cations, CH 4 + , with H 2 , HD and D 2 have been studied in a variable temperature 22-pole ion trap from room temperature down to 15 K. The formation of CH 5 + in collisions with H 2 is slow at 300 K, but it becomes faster by at least one order of magnitude when the temperature is lowered to 15 K. This behavior is tentatively explained with a longer complex lifetime at low temperatures. However, since tunneling is most probably not responsible for product formation, other dynamical or statistical restrictions must be responsible for the negative temperature dependence. In collisions of CH 4 + with HD, the CH 5 + product ion (68% at 15 K) prevails over CH 4 D + (32%). Reaction of CH 4 + with D 2 is found to be much slower than with H 2 or HD. The rate coefficient for converting CH 4 + into CH 3 D + by H-D exchange has been determined to be smaller than 10 -12 cm 3 /s, indicating that scrambling in the CH 6 + complex is very unlikely

  20. Variable temperature ion trap studies of CH{sub 4}{sup +} + H{sub 2}, HD and D{sub 2}: negative temperature dependence and significant isotope effect

    Energy Technology Data Exchange (ETDEWEB)

    Asvany, O.; Savic, I.; Schlemmer, S.; Gerlich, D

    2004-03-08

    Reactions of methane cations, CH{sub 4}{sup +}, with H{sub 2}, HD and D{sub 2} have been studied in a variable temperature 22-pole ion trap from room temperature down to 15 K. The formation of CH{sub 5}{sup +} in collisions with H{sub 2} is slow at 300 K, but it becomes faster by at least one order of magnitude when the temperature is lowered to 15 K. This behavior is tentatively explained with a longer complex lifetime at low temperatures. However, since tunneling is most probably not responsible for product formation, other dynamical or statistical restrictions must be responsible for the negative temperature dependence. In collisions of CH{sub 4}{sup +} with HD, the CH{sub 5}{sup +} product ion (68% at 15 K) prevails over CH{sub 4}D{sup +} (32%). Reaction of CH{sub 4}{sup +} with D{sub 2} is found to be much slower than with H{sub 2} or HD. The rate coefficient for converting CH{sub 4}{sup +} into CH{sub 3}D{sup +} by H-D exchange has been determined to be smaller than 10{sup -12} cm{sup 3}/s, indicating that scrambling in the CH{sub 6}{sup +} complex is very unlikely.

  1. Blastocystis Isolates from Patients with Irritable Bowel Syndrome and from Asymptomatic Carriers Exhibit Similar Parasitological Loads, but Significantly Different Generation Times and Genetic Variability across Multiple Subtypes.

    Directory of Open Access Journals (Sweden)

    Gie-Bele Vargas-Sanchez

    selected, reducing their genetic variability.

  2. Variables contributing to an excellent customer service management profile within the regulated electric utility industry: A comparison of self-concept with customer satisfaction for customer service management

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.E.

    1991-01-01

    This research sought to address the relationship between self-concept and customer satisfaction: can customer satisfaction with a major electric utility be explained in terms of the self-reported, self-concept of the utility's managers The population to which the results of this study were generalized consisted of customer service managers in public electric utilities across the United States. In order to represent this population, a sample was selected consisting of customer service managers at a midwestern electric utility based in a large metropolitan area. Participants in this study were managers of four direct customer contact service organizations within six geographic division organizations. The methodology included comparisons of these four customer contact service organizations on twelve independent, self-concept variables and six customer satisfaction dependent variables using Analysis of Variance (ANOVA), Scheffe' tests, Chi-Square, and Stepwise multiple regression. The groups were found not to be significantly different and knowledge of the self-concept scores for managers will not increase the ability to predict customer satisfaction over no knowledge of self-concept scores.

  3. Variable effects of maternal and paternal-fetal contribution to the risk for preeclampsia combining GSTP1, eNOS, and LPL gene polymorphisms.

    Science.gov (United States)

    Pappa, Kalliopi I; Roubelakis, Maria; Vlachos, George; Marinopoulos, Spyros; Zissou, Antonia; Anagnou, Nicholas P; Antsaklis, Aris

    2011-04-01

    To evaluate the maternal, paternal, and fetal genotype contribution to preeclampsia. STUDY DESIGN, MATERIALS, AND METHODS: We combined the analysis of polymorphisms of the GSTP1, eNOS, and LPL genes - affecting biotransformation enzymes and endothelial function - in a cohort of 167 preeclamptic and normal control trios (mother, father, and child) comprising a total of 501 samples in the Greek population, never analyzed before by this approach. For the frequency of the GSTP1 Ile(105)/Val(105), the eNOS Glu298Asp and the LPL-93 polymorphisms, statistically significant differences were found between the two groups. However, the transmission rates of the parental alleles to neonates studied by the transmission disequilibrium test, disclosed no increased rate of transmission to preeclampsia children for the variant alleles of Val(105) GSTP1, 298Asp eNOS, and -93G LPL. These novel data, suggest that interaction of all three types of genotypes (mother, father and neonate), reveals no effects on the development of preeclampsia, but provide the impetus for further studies to decipher the individual contribution of each genetic parameter of preeclampsia.

  4. SRSF1-3 contributes to diversification of the immunoglobulin variable region gene by promoting accumulation of AID in the nucleus.

    Science.gov (United States)

    Kawaguchi, Yuka; Nariki, Hiroaki; Kawamoto, Naoko; Kanehiro, Yuichi; Miyazaki, Satoshi; Suzuki, Mari; Magari, Masaki; Tokumitsu, Hiroshi; Kanayama, Naoki

    2017-04-01

    Activation-induced cytidine deaminase (AID) is essential for diversification of the Ig variable region (IgV). AID is excluded from the nucleus, where it normally functions. However, the molecular mechanisms responsible for regulating AID localization remain to be elucidated. The SR-protein splicing factor SRSF1 is a nucleocytoplasmic shuttling protein, a splicing isoform of which called SRSF1-3, has previously been shown to contribute to IgV diversification in chicken DT40 cells. In this study, we examined whether SRSF1-3 functions in IgV diversification by promoting nuclear localization of AID. AID expressed alone was localized predominantly in the cytoplasm. In contrast, co-expression of AID with SRSF1-3 led to the nuclear accumulation of both AID and SRSF1-3 and the formation of a protein complex that contained them both, although SRSF1-3 was dispensable for nuclear import of AID. Expression of either SRSF1-3 or a C-terminally-truncated AID mutant increased IgV diversification in DT40 cells. However, overexpression of exogenous SRSF1-3 was unable to further enhance IgV diversification in DT40 cells expressing the truncated AID mutant, although SRSF1-3 was able to form a protein complex with the AID mutant. These results suggest that SRSF1-3 promotes nuclear localization of AID probably by forming a nuclear protein complex, which might stabilize nuclear AID and induce IgV diversification in an AID C-terminus-dependent manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. AAV8 capsid variable regions at the two-fold symmetry axis contribute to high liver transduction by mediating nuclear entry and capsid uncoating

    International Nuclear Information System (INIS)

    Tenney, Rebeca M.; Bell, Christie L.; Wilson, James M.

    2014-01-01

    Adeno-associated virus serotype 8 (AAV8) is a promising vector for liver-directed gene therapy. Although efficient uncoating of viral capsids has been implicated in AAV8's robust liver transduction, much about the biology of AAV8 hepatotropism remains unclear. Our study investigated the structural basis of AAV8 liver transduction efficiency by constructing chimeric vector capsids containing sequences derived from AAV8 and AAV2 – a highly homologous yet poorly hepatotropic serotype. Engineered vectors containing capsid variable regions (VR) VII and IX from AAV8 in an AAV2 backbone mediated near AAV8-like transduction in mouse liver, with higher numbers of chimeric genomes detected in whole liver cells and isolated nuclei. Interestingly, chimeric capsids within liver nuclei also uncoated similarly to AAV8 by 6 weeks after administration, in contrast with AAV2, of which a significantly smaller proportion were uncoated. This study links specific AAV capsid regions to the transduction ability of a clinically relevant AAV serotype. - Highlights: • We construct chimeric vectors to identify determinants of AAV8 liver transduction. • An AAV2-based vector with 17 AAV8 residues exhibited high liver transduction in mice. • This vector also surpassed AAV2 in cell entry, nuclear entry and onset of expression. • Most chimeric vector particles were uncoated at 6 weeks, like AAV8 and unlike AAV2. • Chimera retained heparin binding and was antigenically distinct from AAV2 and AAV8

  6. AAV8 capsid variable regions at the two-fold symmetry axis contribute to high liver transduction by mediating nuclear entry and capsid uncoating

    Energy Technology Data Exchange (ETDEWEB)

    Tenney, Rebeca M.; Bell, Christie L.; Wilson, James M., E-mail: wilsonjm@mail.med.upenn.edu

    2014-04-15

    Adeno-associated virus serotype 8 (AAV8) is a promising vector for liver-directed gene therapy. Although efficient uncoating of viral capsids has been implicated in AAV8's robust liver transduction, much about the biology of AAV8 hepatotropism remains unclear. Our study investigated the structural basis of AAV8 liver transduction efficiency by constructing chimeric vector capsids containing sequences derived from AAV8 and AAV2 – a highly homologous yet poorly hepatotropic serotype. Engineered vectors containing capsid variable regions (VR) VII and IX from AAV8 in an AAV2 backbone mediated near AAV8-like transduction in mouse liver, with higher numbers of chimeric genomes detected in whole liver cells and isolated nuclei. Interestingly, chimeric capsids within liver nuclei also uncoated similarly to AAV8 by 6 weeks after administration, in contrast with AAV2, of which a significantly smaller proportion were uncoated. This study links specific AAV capsid regions to the transduction ability of a clinically relevant AAV serotype. - Highlights: • We construct chimeric vectors to identify determinants of AAV8 liver transduction. • An AAV2-based vector with 17 AAV8 residues exhibited high liver transduction in mice. • This vector also surpassed AAV2 in cell entry, nuclear entry and onset of expression. • Most chimeric vector particles were uncoated at 6 weeks, like AAV8 and unlike AAV2. • Chimera retained heparin binding and was antigenically distinct from AAV2 and AAV8.

  7. EPA Contribution to Manuscript "Evaluation and Error Apportionment of an Ensemble of Atmospheric Chemistry Transport Modelling Systems: Multi-variable Temporal and Spatial Breakdown"

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset contains the data contributed by EPA/ORD/NERL/CED researchers to the manuscript "Evaluation and Error Apportionment of an Ensemble of Atmospheric...

  8. Toxicity screening of soils from different mine areas—A contribution to track the sensitivity and variability of Arthrobacter globiformis assay

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Catarina R., E-mail: crmarques@ua.pt [Departamento de Biologia and CESAM (Centro de Estudos do Ambiente e do Mar), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Caetano, Ana L. [Departamento de Biologia and CESAM (Centro de Estudos do Ambiente e do Mar), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Haller, Andreas [ECT Oekotoxikologie GmbH, Böttgerstraße 2–14, D-65439 Flörsheim a. M. (Germany); Gonçalves, Fernando [Departamento de Biologia and CESAM (Centro de Estudos do Ambiente e do Mar), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Pereira, Ruth [Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto (Portugal); Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Römbke, Jörg [ECT Oekotoxikologie GmbH, Böttgerstraße 2–14, D-65439 Flörsheim a. M. (Germany)

    2014-06-01

    Highlights: • The assay gave rapid and feasible discrimination of toxic soils to A. globiformis. • Sensitive and low variability response to soils from different regions. • Soil properties may interfere with metal toxicity and fluorescence measurements. • Proposal of a toxicity threshold for the contact assay regarding soils. • A. globiformis assay should be included in the Tier I of risk assessment frameworks. - Abstract: This study used the Arthrobacter globiformis solid-contact test for assessing the quality of soils collected in areas subjected to past and present mine activities in Europe (uranium mine, Portugal) and North Africa (phosphogypsum pile, Tunisia; iron mine, Morocco). As to discriminate the influence of soils natural variability from the effect of contaminants, toxicity thresholds were derived for this test, based on the dataset of each study area. Furthermore, the test sensitivity and variability was also evaluated. As a result, soils that inhibited A. globiformis dehydrogenase activity above 45% or 50% relatively to the control, were considered to be toxic. Despite the soil metal content determined, the properties of soils seemed to influence dehydrogenase activity. Overall, the contact test provided a coherent outcome comparing to other more time-consuming and effort-demanding ecotoxicological assays. Our results strengthened the feasibility and ecological relevance of this assay, which variability was quite reduced hence suggesting its potential integration within the test battery of tier 1 of soil risk assessment schemes.

  9. Toxicity screening of soils from different mine areas—A contribution to track the sensitivity and variability of Arthrobacter globiformis assay

    International Nuclear Information System (INIS)

    Marques, Catarina R.; Caetano, Ana L.; Haller, Andreas; Gonçalves, Fernando; Pereira, Ruth; Römbke, Jörg

    2014-01-01

    Highlights: • The assay gave rapid and feasible discrimination of toxic soils to A. globiformis. • Sensitive and low variability response to soils from different regions. • Soil properties may interfere with metal toxicity and fluorescence measurements. • Proposal of a toxicity threshold for the contact assay regarding soils. • A. globiformis assay should be included in the Tier I of risk assessment frameworks. - Abstract: This study used the Arthrobacter globiformis solid-contact test for assessing the quality of soils collected in areas subjected to past and present mine activities in Europe (uranium mine, Portugal) and North Africa (phosphogypsum pile, Tunisia; iron mine, Morocco). As to discriminate the influence of soils natural variability from the effect of contaminants, toxicity thresholds were derived for this test, based on the dataset of each study area. Furthermore, the test sensitivity and variability was also evaluated. As a result, soils that inhibited A. globiformis dehydrogenase activity above 45% or 50% relatively to the control, were considered to be toxic. Despite the soil metal content determined, the properties of soils seemed to influence dehydrogenase activity. Overall, the contact test provided a coherent outcome comparing to other more time-consuming and effort-demanding ecotoxicological assays. Our results strengthened the feasibility and ecological relevance of this assay, which variability was quite reduced hence suggesting its potential integration within the test battery of tier 1 of soil risk assessment schemes

  10. Contribution to the electrothermal simulation in power electronics. Development of a simulation methodology applied to switching circuits under variable operating conditions; Contribution a la simulation electrothermique en electronique de puissance. Developpement d`une methode de simulation pour circuits de commutation soumis a des commandes variables

    Energy Technology Data Exchange (ETDEWEB)

    Vales, P.

    1997-03-19

    In modern hybrid or monolithic integrated power circuits, electrothermal effects can no longer be ignored. A methodology is proposed in order to simulate electrothermal effects in power circuits, with a significant reduction of the computation time while taking into account electrical and thermal time constants which are usually widely different. A supervising program, written in Fortran, uses system call sequences and manages an interactive dialog between a fast thermal simulator and a general electrical simulator. This explicit coupling process between two specific simulators requires a multi-task operating system. The developed software allows for the prediction of the electrothermal power dissipation drift in the active areas of components, and the prediction of thermally-induced coupling effects between adjacent components. An application to the study of hard switching circuits working under variable operating conditions is presented

  11. Significant contributing causes of cancer deaths among Hispanics in Colorado, USA, 1983-1992 Causas que contribuem para óbitos por câncer em latinos no Colorado, EUA, 1983-92

    Directory of Open Access Journals (Sweden)

    Kimberley Sweitzer

    1998-01-01

    Full Text Available Cancer deaths in the state of Colorado, U.S.A., totaled 53,921 between 1983 and 1992. Death certificates for this period were used to evaluate Hispanic cancer deaths by contributing causes of death and primary occupation of the decedent. The relative risks for diabetes and liver disease as contributing causes of death were significantly higher among Hispanics when compared to non-Hispanics who had also died of cancer (RR for diabetes = 1.90; 95% C.I. (1.64,2.19 and RR for liver disease = 1.44; 95% C.I. (1.23,1.68. Hispanics who had died of cancer were significantly less likely to have drug abuse as a contributing cause of death when compared to non-Hispanics (RR for drug abuse = 0.69; 95% C.I. (0.52,0.91. Laborers, service workers, and clerical workers who were Hispanic, were significantly more likely to die of cancer with either diabetes or liver disease as a contributing cause of death than were non-Hispanics in the same occupational category (pEntre 1983 e 1997, ocorreram 53.921 óbitos por câncer no Estado do Colorado, EUA. Os atestados de óbito para este período foram utilizados para avaliar as causas que contribuíram para a morte e a ocupação principal dos óbitos por câncer ocorridos em latinos neste período. Os riscos relativos para diabetes e doença hepática como causas associadas ao óbito foram significativamente maiores em latinos, comparativamente com não latinos que também faleceram com câncer (diabetes RR = 1,90; I.C. 95% 1,64-2,19; doença hepática RR = 1,44; I.C. 95% 1,23-1,68. O consumo de drogas como causa associada à morte entre latinos que faleceram por câncer aparentou ser significativamente menor que em não latinos (RR = 0,69; I.C. 95% 0,52-0,91. Operários, servidores públicos e trabalhadores de escritório de origem latina tenderam a apresentar diabetes e doença hepática como causas associadas à morte por câncer em maior freqüência, estatisticamente significativa, que não latinos nos mesmos ramos

  12. Relative contributions of preprandial and postprandial glucose exposures, glycemic variability, and non-glycemic factors to HbA in individuals with and without diabetes

    DEFF Research Database (Denmark)

    Færch, Kristine; Alssema, Marjan; Mela, David J

    2018-01-01

    BACKGROUND/OBJECTIVE: There is substantial interest in dietary approaches to reducing postprandial glucose (PPG) responses, but the quantitative contribution of PPG to longer-term glycemic control (reflected in glycated hemoglobin, HbA1c) in the general population is not known. This study quantif...

  13. Modeling the contributions of global air temperature, synoptic-scale phenomena and soil moisture to near-surface static energy variability using artificial neural networks

    Science.gov (United States)

    Pryor, Sara C.; Sullivan, Ryan C.; Schoof, Justin T.

    2017-12-01

    The static energy content of the atmosphere is increasing on a global scale, but exhibits important subglobal and subregional scales of variability and is a useful parameter for integrating the net effect of changes in the partitioning of energy at the surface and for improving understanding of the causes of so-called warming holes (i.e., locations with decreasing daily maximum air temperatures (T) or increasing trends of lower magnitude than the global mean). Further, measures of the static energy content (herein the equivalent potential temperature, θe) are more strongly linked to excess human mortality and morbidity than air temperature alone, and have great relevance in understanding causes of past heat-related excess mortality and making projections of possible future events that are likely to be associated with negative human health and economic consequences. New nonlinear statistical models for summertime daily maximum and minimum θe are developed and used to advance understanding of drivers of historical change and variability over the eastern USA. The predictor variables are an index of the daily global mean temperature, daily indices of the synoptic-scale meteorology derived from T and specific humidity (Q) at 850 and 500 hPa geopotential heights (Z), and spatiotemporally averaged soil moisture (text">SM). text">SM is particularly important in determining the magnitude of θe over regions that have previously been identified as exhibiting warming holes, confirming the key importance of text">SM in dictating the partitioning of net radiation into sensible and latent heat and dictating trends in near-surface T and θe. Consistent with our a priori expectations, models built using artificial neural networks (ANNs) out-perform linear models that do not permit interaction of the predictor variables (global T, synoptic-scale meteorological conditions and text">SM). This is particularly marked in regions with high variability in minimum and maximum θe, where

  14. An assessment of the role mass market demand response could play in contributing to the management of variable generation integration issues

    International Nuclear Information System (INIS)

    Cappers, Peter; Mills, Andrew; Goldman, Charles; Wiser, Ryan; Eto, Joseph H.

    2012-01-01

    The penetration of wind and solar generating resources is expected to dramatically increase in the United States over the coming years. It is widely understood that large scale deployment of these types of renewable energy sources (e.g., wind, solar) that have variable and less predictable production characteristics than traditional thermal resources poses integration challenges for bulk power system operators. At present, bulk power system operators primarily utilize strategies that rely on existing thermal generation resources and improved wind and solar energy production forecasts to manage this uncertainty; a host of additional options are also envisioned for the near future including demand response (DR). There are well-established bodies of research that examine variable generation integration issues as well as demand response potential; but, the existing literature that provides a comparative assessment of the two neither treats this topic comprehensively nor in a highly integrated fashion. Thus, this paper seeks to address these missing pieces by considering the full range of opportunities and challenges for mass market DR rates and programs to support integration of variable renewable generation. - Highlights: ► Mass market demand response can help manage the integration of renewable resources. ► To be more effective, retail electricity rates must apply contemporaneous prices. ► Demand response programs will require shorter duration and more frequent events. ► Mass market customers will likely need to accept control technology. ► Market rules and regulatory policies must change to expand demand response's role.

  15. Original contributions

    African Journals Online (AJOL)

    hefere

    Original contributions ... Results suggest that there is a significant positive ... psychological abuse, including economic abuse, intimidation, harassment, stalking, damage ... or maintaining the structure and function of the African home (Alio et al., 2011; Jewkes,. Levin ... Revictimisation occurs due to emotional violence and.

  16. Seasonal variability of iodine and selenium in surface and groundwater as a factor that may contribute to iodine isotope balance in the thyroid gland and its irradiation in case of radioiodine contamination during accidents at the NPP

    Science.gov (United States)

    Korobova, Elena; Kolmykova, Lyudmila; Ryzhenko, Boris; Berezkin, Viktor; Saraeva, Anastasia

    2016-04-01

    Radioiodine release to the environment during the accident at the Chernobyl NPP led to the increased risk of the thyroid cancer cases within the contaminated areas, the effect being aggravated in conditions of stable iodine and selenium deficiency in local food chains. Although the drinking water iodine is usually believed to contribute not more than 10% to local diet, our estimations accounting of water content in other products and several regional studies (e.g. India and Australia) proved its portion to be at least twice as much. As radioiodine isotopes are short-lived, their absorption depends greatly on stable iodine and selenium sufficiency in thyroid gland in the first few days of contamination and seasonal variation of stable iodine and selenium in local sources of drinking water may be significant as modifying the resulting thyroid irradiation in different seasons of the year. The main goal of the study was to evaluate seasonal variation of levels of iodine and selenium in natural waters of the Bryansk region as a possible factor affecting the radioiodine intake by thyroid gland of animals and humans in case of radioiodine contamination during the accident. Seasonal I and Se concentration was measured in the years of 2014 and 2015 at 14 test points characterizing surface (river and lake) and drinking groundwater. Obtained data proved considerable seasonal variation of I and Se concentration in natural waters (3,7-8,1 μg/l and 0,04-0,4 μg/l respectively) related to physico-chemical water parameters, such as pH, Eh and fluctuations in concentration of dissolved organic matter. The widest I and Se seasonal variability was observed in surface and well waters, maximum I level being found in autumn at the end of vegetation period characterized by active I leaching from the decomposed organic residues by long lasting precipitations. The content of selenium in the surface waters during summer-autumn (0,06-0,3 μg/l) was higher than in spring (0,04-0,05

  17. Variability in the contribution of different life stages to population growth as a key factor in the invasion success of Pinus strobus.

    Directory of Open Access Journals (Sweden)

    Zuzana Münzbergová

    Full Text Available Despite the increasing number of studies attempting to model population growth in various organisms, we still know relatively little about the population dynamics of long-lived species that reproduce only in the later stages of their life cycle, such as trees. Predictions of the dynamics of these species are, however, urgently needed for planning management actions when species are either endangered or invasive. In long-lived species, a single management intervention may have consequences for several decades, and detailed knowledge of long-term performance can therefore elucidate possible outcomes during the management planning phase.We studied the population dynamics of an invasive tree species, Pinus strobus, in three habitat types represented by their position along the elevation gradient occupied by the species. In agreement with previous studies on the population dynamics of long-lived perennials, our results show that the survival of the largest trees exhibits the highest elasticity in all of the studied habitats. In contrast, life table response experiments (LTRE analysis showed that different stages contribute the most to population growth rates in different habitats, with generative reproduction being more important in lower slopes and valley bottoms and survival being more important on rock tops and upper slopes.The results indicate that P. strobus exhibits different growth strategies in different habitats that result in similar population growth rates. We propose that this plasticity in growth strategies is a key factor in the invasion success of the white pine. In all of the investigated habitats, the population growth rates are above 1, indicating that the population of the species is still increasing and has the ability to spread and occupy a wide range of habitats.

  18. Inherent X-Linked Genetic Variability and Cellular Mosaicism Unique to Females Contribute to Sex-Related Differences in the Innate Immune Response

    Directory of Open Access Journals (Sweden)

    Zoltan Spolarics

    2017-11-01

    Full Text Available Females have a longer lifespan and better general health than males. Considerable number of studies also demonstrated that, after trauma and sepsis, females present better outcomes as compared to males indicating sex-related differences in the innate immune response. The current notion is that differences in the immuno-modulatory effects of sex hormones are the underlying causative mechanism. However, the field remains controversial and the exclusive role of sex hormones has been challenged. Here, we propose that polymorphic X-linked immune competent genes, which are abundant in the population are important players in sex-based immuno-modulation and play a key role in causing sex-related outcome differences following trauma or sepsis. We describe the differences in X chromosome (ChrX regulation between males and females and its consequences in the context of common X-linked polymorphisms at the individual as well as population level. We also discuss the potential pathophysiological and immune-modulatory aspects of ChrX cellular mosaicism, which is unique to females and how this may contribute to sex-biased immune-modulation. The potential confounding effects of ChrX skewing of cell progenitors at the bone marrow is also presented together with aspects of acute trauma-induced de novo ChrX skewing at the periphery. In support of the hypothesis, novel observations indicating ChrX skewing in a female trauma cohort as well as case studies depicting the temporal relationship between trauma-induced cellular skewing and the clinical course are also described. Finally, we list and discuss a selected set of polymorphic X-linked genes, which are frequent in the population and have key regulatory or metabolic functions in the innate immune response and, therefore, are primary candidates for mediating sex-biased immune responses. We conclude that sex-related differences in a variety of disease processes including the innate inflammatory response to injury

  19. Increased glycemic variability and decrease of the postprandial glucose contribution to HbA1c in obese subjects across the glycemic continuum from normal glycemia to first time diagnosed diabetes.

    Science.gov (United States)

    Fysekidis, Marinos; Cosson, Emmanuel; Banu, Isabela; Duteil, Régine; Cyrille, Chantal; Valensi, Paul

    2014-12-01

    The contribution of postprandial glycemia (PPG) to hyperglycemia has been shown to decrease as HbA1c increased in type 2 diabetic patients. This study aimed at examining, in a series of overweight/obese patients without known glycemic disorder, the contribution of PPG to a "relative" hyperglycemia (glucose values≥5.5 mmol/L) and the presence of glycemic variability according to HbA1c levels. Seventy overweight/obese inpatients (body mass index 35.2±6.8 kg/m2) without known glycemic disorder were included. Participants were classified according to an oral glucose tolerance test (according to the American Diabetes Association criteria) as patients with normoglycemia (n=33), with intermediate hyperglycemia (n=24) or diabetes (n=13). They were separated into HbA1c quartiles (Q1 to Q4). A 24 hour continuous glucose monitoring was used under a 1800 kcal diet and minimal physical activity. We assessed PPG contribution (3 hour period after each meal) to the "relative" 24 hour hyperglycemia (glucose values ≥5.5 mmol/L); the remaining time was considered as the fasting/post-absorptive period. HbA1c range was from 5.1% to 7.4% (32 to 57 mmol/mmol). From the lowest to the highest HbA1c quartile, the area under the curve (AUC) for the "relative" hyperglycemia presented a 17-fold increase for the fasting/post-absorptive (pAUC-3 h AUC for a constant 5.5 mmol/L glycemia)/(total 24 h AUC-24 h AUC for constant 5. 5 mmol/L glycemia)] and decreased from Q1 to Q4 of HbA1c (81.2%, 66%, 65.8%, 57%; pblood glucose level (pglucose variability indices, including mean amplitude of glycemic excursions (p<0.01). In overweight/obese patients, HbA1c was associated with lower PPG contribution to "relative" hyperglycemia and greater glycemic variability. The present findings support the importance of postprandial period in glycemic exposure even before the appearance of diabetes. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Impact of Subsurface Temperature Variability on Meteorological Variability: An AGCM Study

    Science.gov (United States)

    Mahanama, S. P.; Koster, R. D.; Liu, P.

    2006-05-01

    Anomalous atmospheric conditions can lead to surface temperature anomalies, which in turn can lead to temperature anomalies deep in the soil. The deep soil temperature (and the associated ground heat content) has significant memory -- the dissipation of a temperature anomaly may take weeks to months -- and thus deep soil temperature may contribute to the low frequency variability of energy and water variables elsewhere in the system. The memory may even provide some skill to subseasonal and seasonal forecasts. This study uses two long-term AGCM experiments to isolate the contribution of deep soil temperature variability to variability elsewhere in the climate system. The first experiment consists of a standard ensemble of AMIP-type simulations, simulations in which the deep soil temperature variable is allowed to interact with the rest of the system. In the second experiment, the coupling of the deep soil temperature to the rest of the climate system is disabled -- at each grid cell, the local climatological seasonal cycle of deep soil temperature (as determined from the first experiment) is prescribed. By comparing the variability of various atmospheric quantities as generated in the two experiments, we isolate the contribution of interactive deep soil temperature to that variability. The results show that interactive deep soil temperature contributes significantly to surface temperature variability. Interactive deep soil temperature, however, reduces the variability of the hydrological cycle (evaporation and precipitation), largely because it allows for a negative feedback between evaporation and temperature.

  1. Contribution to the study, modelling and optimisation of a variable reluctance machine excited by permanent magnets; Contribution a l'etude, la modelisation et l'optimisation d'une machine a reluctance variable excitee par des aimants permanents

    Energy Technology Data Exchange (ETDEWEB)

    Haouara, I.

    1998-07-01

    Variable reluctance machines (VRM) with double cogs are interesting solutions for gearing mechanisms requiring a strong torque and a low speed. In the case of wind to electricity power conversion they can represent an improvement with the removal of the speed multiplier. A brief classification of VRMs has been made first and then, a double cogs synchronous structure with an excitation system made of permanent magnets included in the rotor has been chosen for this application. Then, using the dimensioning principles of synchronous machines, an approach is proposed to perform its pre-dimensioning. A finite-elements modeling of the machine and a model of equivalent electrical circuit have been used to evaluate its performances. An analytical approach based on the calculation of the air-gap permeation and of the magnetic scalar potential is proposed to identify the parameters of the equivalent electrical circuit (inductances and electromotive force). After validation, this model has been retained for the study of the performances of the generator-rectifier system in real conditions of operation (converter with a high frequency). Finally the optimization of the geometrical and magnetic parameters of the structure is analyzed in order to maximize its power. A conjugate experiment plans and fields calculation method has been used. It allows to take into consideration the real conditions of operation (saturation and dynamical functioning of magnets) and the interaction between the different parameters. The study of an optimized prototype has shown an improvement for all operation modes. (J.S.)

  2. Impact significance determination-Pushing the boundaries

    International Nuclear Information System (INIS)

    Lawrence, David P.

    2007-01-01

    Impact significance determination practice tends to be highly variable. Too often insufficient consideration is given to good practice insights. Also, impact significance determinations are frequently narrowly defined addressing, for example, only individual, negative impacts, focusing on bio-physical impacts, and not seeking to integrate either the Precautionary Principle or sustainability. This article seeks to extend the boundaries of impact significance determination practice by providing an overview of good general impact significance practices, together with stakeholder roles and potential methods for addressing significance determination challenges. Relevant thresholds, criteria, contextual considerations and support methods are also highlighted. The analysis is then extended to address how impact significance determination practices change for positive as compared with negative impacts, for cumulative as compared with individual impacts, for socio-economic as compared with bio-physical impacts, when the Precautionary Principle is integrated into the process, and when sustainability contributions drive the EIA process and related impact significance determinations. These refinements can assist EIA practitioners in ensuring that the scope and nature of impact significance determinations reflect the broadened scope of emerging EIA requirements and practices. Suggestions are included for further refining and testing of the proposed changes to impact significance determination practice

  3. Enamel apatite crystallinity significantly contributes to mammalian dental adaptations

    Czech Academy of Sciences Publication Activity Database

    Kallistová, Anna; Skála, Roman; Šlouf, Miroslav; Čejchan, Petr; Matulková, I.; Horáček, I.

    2018-01-01

    Roč. 8, APR 3 2018 (2018), č. článku 5544. ISSN 2045-2322 R&D Projects: GA MŠk(CZ) LO1507 Institutional support: RVO:67985831 ; RVO:61389013 Keywords : tooth enamel * mechanical -properties * electron-microscopy * diffraction * teeth * size * morphology * behavior * minipig * pattern Subject RIV: EA - Cell Biology; CD - Macromolecular Chemistry (UMCH-V) OBOR OECD: Other biological topics; Polymer science (UMCH-V) Impact factor: 4.259, year: 2016

  4. Requirements to nuclear power to significantly contribute to decarbonization

    Energy Technology Data Exchange (ETDEWEB)

    Zipper, Reinhard [Forschungs- und Technologieberatung Zipper (FTBZ), Haan (Germany)

    2016-06-15

    By the end of the UN Climate Conference 2015 in Paris all members agreed to take action with the goal to limit climate warming to less than 2 C compared to pre-industrial status. CO{sub 2} emissions are supposed to be the main driver of climate change. This implies that all kinds of energy supply must be reengineered to avoid deployment of fossil fuels as far as practicable. Nuclear energy has a minimal CO{sub 2} footprint and with the ability to flexibly adjust to the individual demands of supply regions it may be favored to play a major role in decarbonization. However, on this path some principal obstacles must be removed to gain general public, policy and industry acceptance.

  5. Editorial Prof Lundgren's significant contribution to SAJAA and its ...

    African Journals Online (AJOL)

    low- to middle-income countries,8 and as such, is considered a core component of health.6. Unfortunately, Africa and the ... 40% of global surgery occurs in poor- to middle-income countries.2 As anaesthetists in Africa, we need to focus ... sciences and related medical fields. ASSAf [homepage on the Internet]. 2014. c2015.

  6. Introducing and modeling inefficiency contributions

    DEFF Research Database (Denmark)

    Asmild, Mette; Kronborg, Dorte; Matthews, Kent

    2016-01-01

    -called inefficiency contributions, which are defined as the relative contributions from specific variables to the overall levels of inefficiencies. A statistical model for distinguishing the inefficiency contributions between subgroups is proposed and the method is illustrated on a data set on Chinese banks....

  7. Early onset of significant local warming in low latitude countries

    International Nuclear Information System (INIS)

    Mahlstein, I; Knutti, R; Solomon, S; Portmann, R W

    2011-01-01

    The Earth is warming on average, and most of the global warming of the past half-century can very likely be attributed to human influence. But the climate in particular locations is much more variable, raising the question of where and when local changes could become perceptible enough to be obvious to people in the form of local warming that exceeds interannual variability; indeed only a few studies have addressed the significance of local signals relative to variability. It is well known that the largest total warming is expected to occur in high latitudes, but high latitudes are also subject to the largest variability, delaying the emergence of significant changes there. Here we show that due to the small temperature variability from one year to another, the earliest emergence of significant warming occurs in the summer season in low latitude countries (∼25 deg. S-25 deg. N). We also show that a local warming signal that exceeds past variability is emerging at present, or will likely emerge in the next two decades, in many tropical countries. Further, for most countries worldwide, a mean global warming of 1 deg. C is sufficient for a significant temperature change, which is less than the total warming projected for any economically plausible emission scenario. The most strongly affected countries emit small amounts of CO 2 per capita and have therefore contributed little to the changes in climate that they are beginning to experience.

  8. Local Public Libraries Serve Important Functions as Meeting Places, but Demographic Variables Appear Significant, Suggesting a Need for Extensive Further Research. A Review of: Aabø, S., Audunson, R., & Vårheim, A. (2010. How do public libraries function as meeting places? Library & Information Science Research, 32(1, 16-26. doi: 10.1016/j.lisr.2009.07.008.

    Directory of Open Access Journals (Sweden)

    R. Laval Hunsucker

    2012-03-01

    which a subject trusted various community institutions, and frequency of local library use. “Meeting intensity,” or the number of different meeting types for which a given subject could remember ever having used the library, was one dependent variable. The others were participation/non-participation in each of the six defined meeting types. The researchers employed hierarchical multiple regression analyses for determining degrees of correlation.Main Results – “Meeting intensity” correlated significantly and positively not only with frequency of library use in general, but also with the number of local activities participated in and level of involvement in community improvement activities, as well as with non-Norwegian cultural/linguistic background. It correlated significantly and negatively with household income. The investigators report no significant relationship of meeting intensity with occupational or age category, or with level of education. Participation in certain of the defined meeting types did correlate significantly with certain independent variables. Respondents tend to turn to the local public library more for “public sphere” meetings as they grow older. Participation in this kind of meeting is likewise more common among those with a higher level of community involvement and engagement, but also among the lower-income respondents. High-intensive “joint activities” meetings with friends, acquaintances, colleagues or classmates are especially popular among adults in the lower age categories, as well as among respondents with a lower level of education and with a lower household income. “Virtual” meetings (via library Internet use, also defined as a high-intensive meeting type, are especially popular with the occupational categories “job seeker” and “homemaker,” as well as with the younger respondents and with those who have a lower household income. Use of the local public library for both the “virtual” and the

  9. Significant Tsunami Events

    Science.gov (United States)

    Dunbar, P. K.; Furtney, M.; McLean, S. J.; Sweeney, A. D.

    2014-12-01

    Tsunamis have inflicted death and destruction on the coastlines of the world throughout history. The occurrence of tsunamis and the resulting effects have been collected and studied as far back as the second millennium B.C. The knowledge gained from cataloging and examining these events has led to significant changes in our understanding of tsunamis, tsunami sources, and methods to mitigate the effects of tsunamis. The most significant, not surprisingly, are often the most devastating, such as the 2011 Tohoku, Japan earthquake and tsunami. The goal of this poster is to give a brief overview of the occurrence of tsunamis and then focus specifically on several significant tsunamis. There are various criteria to determine the most significant tsunamis: the number of deaths, amount of damage, maximum runup height, had a major impact on tsunami science or policy, etc. As a result, descriptions will include some of the most costly (2011 Tohoku, Japan), the most deadly (2004 Sumatra, 1883 Krakatau), and the highest runup ever observed (1958 Lituya Bay, Alaska). The discovery of the Cascadia subduction zone as the source of the 1700 Japanese "Orphan" tsunami and a future tsunami threat to the U.S. northwest coast, contributed to the decision to form the U.S. National Tsunami Hazard Mitigation Program. The great Lisbon earthquake of 1755 marked the beginning of the modern era of seismology. Knowledge gained from the 1964 Alaska earthquake and tsunami helped confirm the theory of plate tectonics. The 1946 Alaska, 1952 Kuril Islands, 1960 Chile, 1964 Alaska, and the 2004 Banda Aceh, tsunamis all resulted in warning centers or systems being established.The data descriptions on this poster were extracted from NOAA's National Geophysical Data Center (NGDC) global historical tsunami database. Additional information about these tsunamis, as well as water level data can be found by accessing the NGDC website www.ngdc.noaa.gov/hazard/

  10. The co registration of initial PET on the CT-radiotherapy reduces significantly the variabilities of anatomo-clinical target volume in the child hodgkin disease; La coregistration de la TEP initiale sur la scanographie de radiotherapie diminue significativement les variabilites de volume cible anatomoclinique dans la maladie de Hodgkin de l'enfant

    Energy Technology Data Exchange (ETDEWEB)

    Metwally, H.; Blouet, A.; David, I.; Rives, M.; Izar, F.; Courbon, F.; Filleron, T.; Laprie, A. [Institut Claudius-Regaud, 31 - Toulouse (France); Plat, G.; Vial, J. [CHU-hopital des Enfants, 31 - Toulouse (France)

    2009-10-15

    It exists a great interobserver variability for the anatomo-clinical target volume (C.T.V.) definition in children suffering of Hodgkin disease. In this study, the co-registration of the PET with F.D.G. on the planning computed tomography has significantly lead to a greater coherence in the clinical target volume definition. (N.C.)

  11. Contributions: SAGE

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Contributions: SAGE. Space Alternating Generalized Expectation (SAGE) Maximization algorithm provides an iterative approach to parameter estimation when direct maximization of the likelihood function may be infeasible. Complexity is less in those applications ...

  12. Various Contributions

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Various Contributions. Developed an Off –Diagonal MIMO Canceller to mitigate Upstream Crosstalk in VDSL. Developed a low complexity, Expectation Maximization based iterative Crosstalk cancellation. Developed an optimal way of computational complexity ...

  13. Variability Bugs:

    DEFF Research Database (Denmark)

    Melo, Jean

    . Although many researchers suggest that preprocessor-based variability amplifies maintenance problems, there is little to no hard evidence on how actually variability affects programs and programmers. Specifically, how does variability affect programmers during maintenance tasks (bug finding in particular......)? How much harder is it to debug a program as variability increases? How do developers debug programs with variability? In what ways does variability affect bugs? In this Ph.D. thesis, I set off to address such issues through different perspectives using empirical research (based on controlled...... experiments) in order to understand quantitatively and qualitatively the impact of variability on programmers at bug finding and on buggy programs. From the program (and bug) perspective, the results show that variability is ubiquitous. There appears to be no specific nature of variability bugs that could...

  14. [Job burnout and contributing factors for nurses].

    Science.gov (United States)

    Zhu, Wei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia; Wu, Si-ying

    2006-07-01

    To investigate the degree of job burnout and contributing factors for nurses. A total of 495 nurses from three provincial hospitals were randomly selected. The MBI-GS, EPQ-RSC and OSI-R were administered to measure job burnout, personality traits and occupational stress, respectively. The medical and surgical nurses had significant greater scores of job burnout than others (P < 0.05). The poorer educational background was correlated with lower professional efficacy. The younger nurses had stronger feeling of job burnout. The scores of job burnout changed with different personality traits. The main contributing variables to exhaustion were overload, sense of responsibility, role insufficient and self-care (P < 0.05). The main contributing variables to cynicism were role insufficiency, role boundary, sense of responsibility and self-care (P < 0.05). The main contributing variables to professional inefficacy were role insufficiency, social support and rational/cognitive coping (P < 0.05). Job burnout for nurses can be prevented by reducing or keeping moderate professional duties and responsibility, making clearer job descriptions, promoting leisure activities, and enhancing self-care capabilities.

  15. Social Contributions in Romania

    Directory of Open Access Journals (Sweden)

    Attila Gyorgy

    2012-12-01

    Full Text Available Social contributions have an important impact on payroll policy. Also, social contributions represent a significant budgetary revenue item which can be viewed at the edge between taxation and insurance. Social contributions in Romania experienced many changes which ended in 2008. Nowadays, they are within a long transaction period towards partial externalization of the insurance activity to privately managed funds. The aim of this paper is to analyse the homogeneity of Romanian social security public scheme using annual data extracted from 2002-2009.The main findings reveal that social contributions reached the pinnacle of diversification, being too many, some of them with a small contribution rates; fiscal reforms which reduced contribution rates advantaged employers, and state will be interested to externalize this activity as far private sector will be able to assume this responsibility and the budgetary effects are acceptable for the public finance.

  16. Suicidal Ideation and Schizophrenia: Contribution of Appraisal, Stigmatization, and Cognition.

    Science.gov (United States)

    Stip, Emmanuel; Caron, Jean; Tousignant, Michel; Lecomte, Yves

    2017-10-01

    To predict suicidal ideation in people with schizophrenia, certain studies have measured its relationship with the variables of defeat and entrapment. The relationships are positive, but their interactions remain undefined. To further their understanding, this research sought to measure the relationship between suicidal ideation with the variables of loss, entrapment, and humiliation. The convenience sample included 30 patients with schizophrenia spectrum disorders. The study was prospective (3 measurement times) during a 6-month period. Results were analyzed by stepwise multiple regression. The contribution of the 3 variables to the variance of suicidal ideation was not significant at any of the 3 times (T1: 16.2%, P = 0.056; T2: 19.9%, P = 0.117; T3: 11.2%, P = 0.109). Further analyses measured the relationship between the variables of stigmatization, perceived cognitive dysfunction, symptoms, depression, self-esteem, reason to live, spirituality, social provision, and suicidal ideation. Stepwise multiple regression demonstrated that the contribution of the variables of stigmatization and perceived cognitive dysfunction to the variance of suicidal ideation was significant at all 3 times (T1: 41.7.5%, P = 0.000; T2: 35.2%, P = 0.001; T3: 21.5%, P = 0.012). Yet, over time, the individual contribution of the variables changed: T1, stigmatization (β = 0.518; P = 0.002); T2, stigmatization (β = 0.394; P = 0.025) and perceived cognitive dysfunction (β = 0.349; P = 0.046). Then, at T3, only perceived cognitive dysfunction contributed significantly to suicidal ideation (β = 0.438; P = 0.016). The results highlight the importance of the contribution of the variables of perceived cognitive dysfunction and stigmatization in the onset of suicidal ideation in people with schizophrenia spectrum disorders.

  17. Suicidal Ideation and Schizophrenia: Contribution of Appraisal, Stigmatization, and Cognition

    Science.gov (United States)

    Stip, Emmanuel; Caron, Jean; Tousignant, Michel

    2017-01-01

    Objective: To predict suicidal ideation in people with schizophrenia, certain studies have measured its relationship with the variables of defeat and entrapment. The relationships are positive, but their interactions remain undefined. To further their understanding, this research sought to measure the relationship between suicidal ideation with the variables of loss, entrapment, and humiliation. Method: The convenience sample included 30 patients with schizophrenia spectrum disorders. The study was prospective (3 measurement times) during a 6-month period. Results were analyzed by stepwise multiple regression. Results: The contribution of the 3 variables to the variance of suicidal ideation was not significant at any of the 3 times (T1: 16.2%, P = 0.056; T2: 19.9%, P = 0.117; T3: 11.2%, P = 0.109). Further analyses measured the relationship between the variables of stigmatization, perceived cognitive dysfunction, symptoms, depression, self-esteem, reason to live, spirituality, social provision, and suicidal ideation. Stepwise multiple regression demonstrated that the contribution of the variables of stigmatization and perceived cognitive dysfunction to the variance of suicidal ideation was significant at all 3 times (T1: 41.7.5%, P = 0.000; T2: 35.2%, P = 0.001; T3: 21.5%, P = 0.012). Yet, over time, the individual contribution of the variables changed: T1, stigmatization (β = 0.518; P = 0.002); T2, stigmatization (β = 0.394; P = 0.025) and perceived cognitive dysfunction (β = 0.349; P = 0.046). Then, at T3, only perceived cognitive dysfunction contributed significantly to suicidal ideation (β = 0.438; P = 0.016). Conclusion: The results highlight the importance of the contribution of the variables of perceived cognitive dysfunction and stigmatization in the onset of suicidal ideation in people with schizophrenia spectrum disorders. PMID:28673099

  18. Pulsating variables

    International Nuclear Information System (INIS)

    1989-01-01

    The study of stellar pulsations is a major route to the understanding of stellar structure and evolution. At the South African Astronomical Observatory (SAAO) the following stellar pulsation studies were undertaken: rapidly oscillating Ap stars; solar-like oscillations in stars; 8-Scuti type variability in a classical Am star; Beta Cephei variables; a pulsating white dwarf and its companion; RR Lyrae variables and galactic Cepheids. 4 figs

  19. Cognitive Variability

    Science.gov (United States)

    Siegler, Robert S.

    2007-01-01

    Children's thinking is highly variable at every level of analysis, from neural and associative levels to the level of strategies, theories, and other aspects of high-level cognition. This variability exists within people as well as between them; individual children often rely on different strategies or representations on closely related problems…

  20. The Significance of Normativity

    DEFF Research Database (Denmark)

    Presskorn-Thygesen, Thomas

    and Weber. It does so by situating Durkheim and Weber in the context of Neo-Kantian philosophy, which prevailed among their contemporaries, and the chapter thereby reveals a series of under-thematised similarities not only with regard to their methodological positions, but also in their conception of social...... of social theory. In pursuing this overall research agenda, the dissertation contributes to a number of specific research literatures. Following two introductory and methodological chapters, Chapter 3 thus critically examines the analysis of normativity suggested in the recent attempts at transforming...... the methods of neo-classical economics into a broader form of social theory. The chapter thereby contributes to the critical discourses, particularly in philosophy of science, that challenge the validity of neo-classical economics and its underlying conception of practical rationality. In examining...

  1. Detecting Novelty and Significance

    Science.gov (United States)

    Ferrari, Vera; Bradley, Margaret M.; Codispoti, Maurizio; Lang, Peter J.

    2013-01-01

    Studies of cognition often use an “oddball” paradigm to study effects of stimulus novelty and significance on information processing. However, an oddball tends to be perceptually more novel than the standard, repeated stimulus as well as more relevant to the ongoing task, making it difficult to disentangle effects due to perceptual novelty and stimulus significance. In the current study, effects of perceptual novelty and significance on ERPs were assessed in a passive viewing context by presenting repeated and novel pictures (natural scenes) that either signaled significant information regarding the current context or not. A fronto-central N2 component was primarily affected by perceptual novelty, whereas a centro-parietal P3 component was modulated by both stimulus significance and novelty. The data support an interpretation that the N2 reflects perceptual fluency and is attenuated when a current stimulus matches an active memory representation and that the amplitude of the P3 reflects stimulus meaning and significance. PMID:19400680

  2. Significant NRC Enforcement Actions

    Data.gov (United States)

    Nuclear Regulatory Commission — This dataset provides a list of Nuclear Regulartory Commission (NRC) issued significant enforcement actions. These actions, referred to as "escalated", are issued by...

  3. Significance evaluation in factor graphs

    DEFF Research Database (Denmark)

    Madsen, Tobias; Hobolth, Asger; Jensen, Jens Ledet

    2017-01-01

    in genomics and the multiple-testing issues accompanying them, accurate significance evaluation is of great importance. We here address the problem of evaluating statistical significance of observations from factor graph models. Results Two novel numerical approximations for evaluation of statistical...... significance are presented. First a method using importance sampling. Second a saddlepoint approximation based method. We develop algorithms to efficiently compute the approximations and compare them to naive sampling and the normal approximation. The individual merits of the methods are analysed both from....... Conclusions The applicability of saddlepoint approximation and importance sampling is demonstrated on known models in the factor graph framework. Using the two methods we can substantially improve computational cost without compromising accuracy. This contribution allows analyses of large datasets...

  4. Complex variables

    CERN Document Server

    Fisher, Stephen D

    1999-01-01

    The most important topics in the theory and application of complex variables receive a thorough, coherent treatment in this introductory text. Intended for undergraduates or graduate students in science, mathematics, and engineering, this volume features hundreds of solved examples, exercises, and applications designed to foster a complete understanding of complex variables as well as an appreciation of their mathematical beauty and elegance. Prerequisites are minimal; a three-semester course in calculus will suffice to prepare students for discussions of these topics: the complex plane, basic

  5. Contribution of village cooperation unit in improving farmers incomes

    Science.gov (United States)

    Sibuea, M. B.; Sibuea, F. A.

    2018-02-01

    One of the government and private efforts to improve people’s welfare particularly to improve farmer’s income is to activate the Village Cooperation Unit (KUD). The objective of research was to know the efficiency level of farming organized by farmers together with cooperative. Theoretically some social economic variables have been known influences the rate of farmer’s income, therefore three social variables, such us the level of cooperation services, members participation and friendship among farmers with cooperation were studied. List of questions divided into forty family’s leader members of KUD which become samples. Analysis models were used production function of Cob-Douglass and Output Input Ratio models. It was concluded that level of participation and friendship partially were significantly to the income’s rate meanwhile variable of cooperation services level were not significant. Simultaneously, three factors gave very significant contribution, where R-square was 0.97 so that very significant. It’s also concluded that the biggest contribution given by the friendship level. Efficiency level or farming efforts of the farmers is very well and feasible with the average of OIR rate 19.23. This research recommended that this effort could be improved from friendship process among institution since the contribution was significantly improving the farmer’s income.

  6. Variable stars

    International Nuclear Information System (INIS)

    Feast, M.W.; Wenzel, W.; Fernie, J.D.; Percy, J.R.; Smak, J.; Gascoigne, S.C.B.; Grindley, J.E.; Lovell, B.; Sawyer Hogg, H.B.; Baker, N.; Fitch, W.S.; Rosino, L.; Gursky, H.

    1976-01-01

    A critical review of variable stars is presented. A fairly complete summary of major developments and discoveries during the period 1973-1975 is given. The broad developments and new trends are outlined. Essential problems for future research are identified. (B.R.H. )

  7. Panel acoustic contribution analysis.

    Science.gov (United States)

    Wu, Sean F; Natarajan, Logesh Kumar

    2013-02-01

    Formulations are derived to analyze the relative panel acoustic contributions of a vibrating structure. The essence of this analysis is to correlate the acoustic power flow from each panel to the radiated acoustic pressure at any field point. The acoustic power is obtained by integrating the normal component of the surface acoustic intensity, which is the product of the surface acoustic pressure and normal surface velocity reconstructed by using the Helmholtz equation least squares based nearfield acoustical holography, over each panel. The significance of this methodology is that it enables one to analyze and rank relative acoustic contributions of individual panels of a complex vibrating structure to acoustic radiation anywhere in the field based on a single set of the acoustic pressures measured in the near field. Moreover, this approach is valid for both interior and exterior regions. Examples of using this method to analyze and rank the relative acoustic contributions of a scaled vehicle cabin are demonstrated.

  8. The contribution of internal resources, external resources, and emotional distress to use of drugs and alcohol among Israeli Jewish urban adolescents.

    Science.gov (United States)

    Lipschitz-Elhawi, Racheli; Itzhaky, Haya

    2014-03-01

    The contribution of selected background variables (age, gender), internal resources (mastery, emotional maturity), external resources (parental and peer support), and emotional distress to alcohol and drug use among 160 Israeli Jewish urban high school students were examined. Analyzing the variables with hierarchical regression, emotional distress contributed most significantly to both alcohol and drug use, and the contribution of age was somewhat less significant for both of them. Emotional distress also contributed indirectly to drug use through an interaction with one's sense of mastery. Gender, internal resources, and external resources contributed differentially to alcohol and drug use. Whereas gender and internal resources contributed only to drug use, external resources contributed only to alcohol use. Specifically, peer support contributed positively to alcohol use whereas parental support contributed negatively. The discussion provides explanations for these research findings and their implications, and the research's limitations are noted.

  9. Environmental knowledge. Empirical contributions according to the significance of scientific knowledge in the scope of envionmental education exemplified at BIODIESEL as a fuel; Umweltwissen und oekologisches Handeln. Empirische Beitraege zur Bedeutung naturwissenschaftlicher Bildung im Rahmen der Umwelterziehung am Beispiel der Verwendung von BIODIESEL als Treibstoff fuer moderne Dieselkraftfahrzeuge

    Energy Technology Data Exchange (ETDEWEB)

    Hantke, Guenter

    2006-09-15

    The world-wide heating up of the atmosphere as well as the increasing violence and frequency of extreme weather events mainly are due to the emission of carbon dioxide. The emission of carbon dioxide is based on the power production by combustion of fossil sources of energy. The motor traffic causes a substantial portion of these emissions. Under this aspect, the author of the contribution under consideration examines, to what extent young people are sensitized to the relation between power generation by burning fossil sources of energy and the global climatic change and to ecological acting. In the context of the environment project 'Biodiesel as a pollution-free alternative to mineral diesel oil', 55 young people were informed about these relations and interviewed afterwards. After this project, a fifth of the young people transferred to economical diesel engined vehicles. A third of the young person wants to drive with biodiesel based on economic considerations. Young peoples only have a small amount of knowledge on these relations. Only those young people, who drive with biodiesel, are informed better significantly.

  10. Testing Significance Testing

    Directory of Open Access Journals (Sweden)

    Joachim I. Krueger

    2018-04-01

    Full Text Available The practice of Significance Testing (ST remains widespread in psychological science despite continual criticism of its flaws and abuses. Using simulation experiments, we address four concerns about ST and for two of these we compare ST’s performance with prominent alternatives. We find the following: First, the 'p' values delivered by ST predict the posterior probability of the tested hypothesis well under many research conditions. Second, low 'p' values support inductive inferences because they are most likely to occur when the tested hypothesis is false. Third, 'p' values track likelihood ratios without raising the uncertainties of relative inference. Fourth, 'p' values predict the replicability of research findings better than confidence intervals do. Given these results, we conclude that 'p' values may be used judiciously as a heuristic tool for inductive inference. Yet, 'p' values cannot bear the full burden of inference. We encourage researchers to be flexible in their selection and use of statistical methods.

  11. Safety significance evaluation system

    International Nuclear Information System (INIS)

    Lew, B.S.; Yee, D.; Brewer, W.K.; Quattro, P.J.; Kirby, K.D.

    1991-01-01

    This paper reports that the Pacific Gas and Electric Company (PG and E), in cooperation with ABZ, Incorporated and Science Applications International Corporation (SAIC), investigated the use of artificial intelligence-based programming techniques to assist utility personnel in regulatory compliance problems. The result of this investigation is that artificial intelligence-based programming techniques can successfully be applied to this problem. To demonstrate this, a general methodology was developed and several prototype systems based on this methodology were developed. The prototypes address U.S. Nuclear Regulatory Commission (NRC) event reportability requirements, technical specification compliance based on plant equipment status, and quality assurance assistance. This collection of prototype modules is named the safety significance evaluation system

  12. Predicting significant torso trauma.

    Science.gov (United States)

    Nirula, Ram; Talmor, Daniel; Brasel, Karen

    2005-07-01

    Identification of motor vehicle crash (MVC) characteristics associated with thoracoabdominal injury would advance the development of automatic crash notification systems (ACNS) by improving triage and response times. Our objective was to determine the relationships between MVC characteristics and thoracoabdominal trauma to develop a torso injury probability model. Drivers involved in crashes from 1993 to 2001 within the National Automotive Sampling System were reviewed. Relationships between torso injury and MVC characteristics were assessed using multivariate logistic regression. Receiver operating characteristic curves were used to compare the model to current ACNS models. There were a total of 56,466 drivers. Age, ejection, braking, avoidance, velocity, restraints, passenger-side impact, rollover, and vehicle weight and type were associated with injury (p < 0.05). The area under the receiver operating characteristic curve (83.9) was significantly greater than current ACNS models. We have developed a thoracoabdominal injury probability model that may improve patient triage when used with ACNS.

  13. Gas revenue increasingly significant

    International Nuclear Information System (INIS)

    Megill, R.E.

    1991-01-01

    This paper briefly describes the wellhead prices of natural gas compared to crude oil over the past 70 years. Although natural gas prices have never reached price parity with crude oil, the relative value of a gas BTU has been increasing. It is one of the reasons that the total amount of money coming from natural gas wells is becoming more significant. From 1920 to 1955 the revenue at the wellhead for natural gas was only about 10% of the money received by producers. Most of the money needed for exploration, development, and production came from crude oil. At present, however, over 40% of the money from the upstream portion of the petroleum industry is from natural gas. As a result, in a few short years natural gas may become 50% of the money revenues generated from wellhead production facilities

  14. Complex variables

    CERN Document Server

    Flanigan, Francis J

    2010-01-01

    A caution to mathematics professors: Complex Variables does not follow conventional outlines of course material. One reviewer noting its originality wrote: ""A standard text is often preferred [to a superior text like this] because the professor knows the order of topics and the problems, and doesn't really have to pay attention to the text. He can go to class without preparation."" Not so here-Dr. Flanigan treats this most important field of contemporary mathematics in a most unusual way. While all the material for an advanced undergraduate or first-year graduate course is covered, discussion

  15. Tumor significant dose

    International Nuclear Information System (INIS)

    Supe, S.J.; Nagalaxmi, K.V.; Meenakshi, L.

    1983-01-01

    In the practice of radiotherapy, various concepts like NSD, CRE, TDF, and BIR are being used to evaluate the biological effectiveness of the treatment schedules on the normal tissues. This has been accepted as the tolerance of the normal tissue is the limiting factor in the treatment of cancers. At present when various schedules are tried, attention is therefore paid to the biological damage of the normal tissues only and it is expected that the damage to the cancerous tissues would be extensive enough to control the cancer. Attempt is made in the present work to evaluate the concent of tumor significant dose (TSD) which will represent the damage to the cancerous tissue. Strandquist in the analysis of a large number of cases of squamous cell carcinoma found that for the 5 fraction/week treatment, the total dose required to bring about the same damage for the cancerous tissue is proportional to T/sup -0.22/, where T is the overall time over which the dose is delivered. Using this finding the TSD was defined as DxN/sup -p/xT/sup -q/, where D is the total dose, N the number of fractions, T the overall time p and q are the exponents to be suitably chosen. The values of p and q are adjusted such that p+q< or =0.24, and p varies from 0.0 to 0.24 and q varies from 0.0 to 0.22. Cases of cancer of cervix uteri treated between 1978 and 1980 in the V. N. Cancer Centre, Kuppuswamy Naidu Memorial Hospital, Coimbatore, India were analyzed on the basis of these formulations. These data, coupled with the clinical experience, were used for choice of a formula for the TSD. Further, the dose schedules used in the British Institute of Radiology fraction- ation studies were also used to propose that the tumor significant dose is represented by DxN/sup -0.18/xT/sup -0.06/

  16. Uranium chemistry: significant advances

    International Nuclear Information System (INIS)

    Mazzanti, M.

    2011-01-01

    The author reviews recent progress in uranium chemistry achieved in CEA laboratories. Like its neighbors in the Mendeleev chart uranium undergoes hydrolysis, oxidation and disproportionation reactions which make the chemistry of these species in water highly complex. The study of the chemistry of uranium in an anhydrous medium has led to correlate the structural and electronic differences observed in the interaction of uranium(III) and the lanthanides(III) with nitrogen or sulfur molecules and the effectiveness of these molecules in An(III)/Ln(III) separation via liquid-liquid extraction. Recent work on the redox reactivity of trivalent uranium U(III) in an organic medium with molecules such as water or an azide ion (N 3 - ) in stoichiometric quantities, led to extremely interesting uranium aggregates particular those involved in actinide migration in the environment or in aggregation problems in the fuel processing cycle. Another significant advance was the discovery of a compound containing the uranyl ion with a degree of oxidation (V) UO 2 + , obtained by oxidation of uranium(III). Recently chemists have succeeded in blocking the disproportionation reaction of uranyl(V) and in stabilizing polymetallic complexes of uranyl(V), opening the way to to a systematic study of the reactivity and the electronic and magnetic properties of uranyl(V) compounds. (A.C.)

  17. Meaning and significance of

    Directory of Open Access Journals (Sweden)

    Ph D Student Roman Mihaela

    2011-05-01

    Full Text Available The concept of "public accountability" is a challenge for political science as a new concept in this area in full debate and developement ,both in theory and practice. This paper is a theoretical approach of displaying some definitions, relevant meanings and significance odf the concept in political science. The importance of this concept is that although originally it was used as a tool to improve effectiveness and eficiency of public governance, it has gradually become a purpose it itself. "Accountability" has become an image of good governance first in the United States of America then in the European Union.Nevertheless,the concept is vaguely defined and provides ambiguous images of good governance.This paper begins with the presentation of some general meanings of the concept as they emerge from specialized dictionaries and ancyclopaedies and continues with the meanings developed in political science. The concept of "public accontability" is rooted in economics and management literature,becoming increasingly relevant in today's political science both in theory and discourse as well as in practice in formulating and evaluating public policies. A first conclusin that emerges from, the analysis of the evolution of this term is that it requires a conceptual clarification in political science. A clear definition will then enable an appropriate model of proving the system of public accountability in formulating and assessing public policies, in order to implement a system of assessment and monitoring thereof.

  18. Theoretical basis and significance of the variance of discharge as a bidimensional variable for the design of lateral lines of micro-irrigation Bases teóricas e importância da variância da vazão como variável bidimensional no dimensionamento de linhas laterais em microirrigação

    Directory of Open Access Journals (Sweden)

    Euro Roberto Detomini

    2009-08-01

    Full Text Available In order to support the theoretical basis and contribute to the improvement of educational capability issues relating to irrigation systems design, this point of view presents an alternative deduction of the variance of the discharge as a bidimensional and independent random variable. Then a subsequent brief application of an existing model is applied for statistical design of laterals in micro-irrigation. The better manufacturing precision of emitters allows lengthening a lateral for a given soil slope, although this does not necessarily mean that the statistical uniformity throughout the lateral will be more homogenous.Visando a reforçar as bases teóricas e contribuir com a melhoria da capacitação educacional em assuntos relacionados a dimensionamento de sistemas de irrigação, o presente ponto de vista revela uma dedução alternativa para a variância da vazão dos emissores, variável aleatória independente bidimensional. Posteriormente apresenta breve aplicação do modelo aceito para dimensionamento de linhas laterais em sistemas de microirrigação, de acordo com a abordagem estatística. A melhor precisão na fabricação de emssores permite, para uma dada inclinação de terreno, dimensionar laterais mais longas, o que não significa necessariamente que uniformidade de emissão dessas laterais será projetada como mais homogênea.

  19. Significant Radionuclides Determination

    Energy Technology Data Exchange (ETDEWEB)

    Jo A. Ziegler

    2001-07-31

    The purpose of this calculation is to identify radionuclides that are significant to offsite doses from potential preclosure events for spent nuclear fuel (SNF) and high-level radioactive waste expected to be received at the potential Monitored Geologic Repository (MGR). In this calculation, high-level radioactive waste is included in references to DOE SNF. A previous document, ''DOE SNF DBE Offsite Dose Calculations'' (CRWMS M&O 1999b), calculated the source terms and offsite doses for Department of Energy (DOE) and Naval SNF for use in design basis event analyses. This calculation reproduces only DOE SNF work (i.e., no naval SNF work is included in this calculation) created in ''DOE SNF DBE Offsite Dose Calculations'' and expands the calculation to include DOE SNF expected to produce a high dose consequence (even though the quantity of the SNF is expected to be small) and SNF owned by commercial nuclear power producers. The calculation does not address any specific off-normal/DBE event scenarios for receiving, handling, or packaging of SNF. The results of this calculation are developed for comparative analysis to establish the important radionuclides and do not represent the final source terms to be used for license application. This calculation will be used as input to preclosure safety analyses and is performed in accordance with procedure AP-3.12Q, ''Calculations'', and is subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (DOE 2000) as determined by the activity evaluation contained in ''Technical Work Plan for: Preclosure Safety Analysis, TWP-MGR-SE-000010'' (CRWMS M&O 2000b) in accordance with procedure AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''.

  20. Individual Movement Variability Magnitudes Are Explained by Cortical Neural Variability.

    Science.gov (United States)

    Haar, Shlomi; Donchin, Opher; Dinstein, Ilan

    2017-09-13

    Humans exhibit considerable motor variability even across trivial reaching movements. This variability can be separated into specific kinematic components such as extent and direction that are thought to be governed by distinct neural processes. Here, we report that individual subjects (males and females) exhibit different magnitudes of kinematic variability, which are consistent (within individual) across movements to different targets and regardless of which arm (right or left) was used to perform the movements. Simultaneous fMRI recordings revealed that the same subjects also exhibited different magnitudes of fMRI variability across movements in a variety of motor system areas. These fMRI variability magnitudes were also consistent across movements to different targets when performed with either arm. Cortical fMRI variability in the posterior-parietal cortex of individual subjects explained their movement-extent variability. This relationship was apparent only in posterior-parietal cortex and not in other motor system areas, thereby suggesting that individuals with more variable movement preparation exhibit larger kinematic variability. We therefore propose that neural and kinematic variability are reliable and interrelated individual characteristics that may predispose individual subjects to exhibit distinct motor capabilities. SIGNIFICANCE STATEMENT Neural activity and movement kinematics are remarkably variable. Although intertrial variability is rarely studied, here, we demonstrate that individual human subjects exhibit distinct magnitudes of neural and kinematic variability that are reproducible across movements to different targets and when performing these movements with either arm. Furthermore, when examining the relationship between cortical variability and movement variability, we find that cortical fMRI variability in parietal cortex of individual subjects explained their movement extent variability. This enabled us to explain why some subjects

  1. Campaign contributions, lobbying and post-Katrina contracts.

    Science.gov (United States)

    Hogan, Michael J; Long, Michael A; Stretesky, Paul B

    2010-07-01

    This research explores the relationship between political campaign contributions, lobbying and post-Hurricane Katrina cleanup and reconstruction contracts. Specifically, a case-control study design is used to determine whether campaign contributions to national candidates in the 2000-04 election cycles and/or the employment of lobbyists and lobbying firms increased a company's probability of receiving a post-hurricane contract. Results indicate that both a campaign contribution dichotomous variable and the dollar amount of contributions are significantly related to whether a company received a contract, but that lobbying activity was not. These findings are discussed in the context of previous research on the politics of natural disasters, government contracting and governmental and corporate deviance.

  2. Impact significance determination-Back to basics

    International Nuclear Information System (INIS)

    Lawrence, David P.

    2007-01-01

    Impact significance determination is widely recognized as a vital and critical EIA activity. But impact significance related concepts are poorly understood. And the quality of approaches for impact significance determination in EIA practice remains highly variable. This article seeks to help establish a sound and practical conceptual foundation for formulating and evaluating impact significance determination approaches. It addresses the nature (what is impact significance?), the core characteristics (what are the major properties of significance determination?), the rationale (why are impact significance determinations necessary?), the procedural and substantive objectives (what do impact significance determinations seek to achieve?), and the process for making impact significance judgments (how is impact significance determination conducted?). By identifying fundamental attributes and key distinctions associated with impact significance determinations, a basis is provided for designing and evaluating impact significance determination procedures at both the regulatory and applied levels

  3. Bank Stock Returns in Responding the Contribution of Fundamental and Macroeconomic Effects

    Directory of Open Access Journals (Sweden)

    Ridwan Nurazi

    2016-06-01

    Full Text Available This study attempts to examine the effect of financial fundamentals information using CAMELS ratios and macroeconomics variables surrogated by interest rate, exchange rate, and inflation rate toward stock return. By employing panel data analysis (Pooled Least Squared Model, the results reveal that several financial ratios perform a bit contrary to the theory, in which the ratio of CAR shows positive sign but insignificantly contributes to stock returns. Also, the ratio of NPL does not affect the return. In fact, ROE and LDR positively and significantly contribute toward banks’ stock return. Meanwhile, NIM and BOPO show negative signs. The other macroeconomic variables, interest rate (IR, exchange rate (ER and inflation rate (INF are consistent with the a priori expectation, in which those variables negatively and significantly contribute to stock return of 16 banks, for the observation period from 2002 to 2011 in the Indonesian banking sector.

  4. Avaliação da qualidade de vida geral de agentes comunitários de saúde: a contribuição relativa das variáveis sociodemográficas e dos domínios da qualidade de vida Evaluation of overall quality of life of community health agents: the relative contribution of sociodemographic variables and domains of quality of life

    Directory of Open Access Journals (Sweden)

    Ana Cláudia G. C. Kluthcovsky

    2007-08-01

    (86.2% of the total. The World Health Organization Quality of Life Instrument Bref was used as a generic instrument to evaluate quality of life. Correlation tests and multivariate linear regression were used, considering a significance level of 5%. RESULTS: None of the sociodemographic variables significantly interfered with overall quality of life. Among the four domains, the physical domain contributed the most to overall quality of life, followed by the psychological and environment domains, all of them accounting for 47.9% of variance. The domain of social relationships did not show significant contribution to overall quality of life. CONCLUSION: It was observed that variance of overall quality of life was not completely explained by sociodemographic variables neither by quality of life domains. Thus, more attention should be given by researchers to different forms of understanding quality of life, especially research methods and interdisciplinary evaluation.

  5. Clinical significance of the fabella

    International Nuclear Information System (INIS)

    Dodevski, A.; Lazarova-Tosovska, D.; Zhivadinovik, J.; Lazareska, M.

    2012-01-01

    Full text: Introduction: There is variable number of sesamoid bones in the human body; one of them is fabella, located in the tendon of the gastrocnemius muscle. Aim of this study was to investigate the frequency of occurrence of fabella in the Macedonian population and to discuss about clinical importance of this bone. Materials and methods: We retrospectively examined radiographs of 53 patients who had knee exams undertaken for a variety of clinical reasons, performed as a part of their medical treatment. Over a time span of six months, 53 patients (38 males and 15 females, age range 19-60 years, mean age of 36.7±12.3 years) were examined. Results: In seven (13.2%) patients of 53 analyzed reports, fabella was found in the lateral tendon of gastrocnemius muscle. We did not find a significant gender or side difference in the appearance of fabella. Conclusion: Although anatomic studies emphasized a lack of significance of the fabella, this bone has been associated with a spectrum of pathology affecting the knee as fabellar syndrome, perineal nerve injury and fracture. We should think of this sesamoid bone while performing diagnostic and surgical procedures

  6. Do psychological variables affect early surgical recovery?

    Directory of Open Access Journals (Sweden)

    Michael N Mavros

    Full Text Available BACKGROUND: Numerous studies have examined the effect of psychological variables on surgical recovery, but no definite conclusion has been reached yet. We sought to examine whether psychological factors influence early surgical recovery. METHODS: We performed a systematic search in PubMed, Scopus and PsycINFO databases to identify studies examining the association of preoperative psychological variables or interventions with objectively measured, early surgical outcomes. RESULTS: We identified 16 eligible studies, 15 of which reported a significant association between at least one psychological variable or intervention and an early postoperative outcome. However, most studies also reported psychological factors not influencing surgical recovery and there was significant heterogeneity across the studies. Overall, trait and state anxiety, state anger, active coping, subclinical depression, and intramarital hostility appeared to complicate recovery, while dispositional optimism, religiousness, anger control, low pain expectations, and external locus of control seemed to promote healing. Psychological interventions (guided relaxation, couple support visit, and psychiatric interview also appeared to favor recovery. Psychological factors unrelated to surgical outcomes included loneliness, perceived social support, anger expression, and trait anger. CONCLUSION: Although the heterogeneity of the available evidence precludes any safe conclusions, psychological variables appear to be associated with early surgical recovery; this association could bear important implications for clinical practice. Large clinical trials and further analyses are needed to precisely evaluate the contribution of psychology in surgical recovery.

  7. INTER-EXAMINER VARIABILITY

    African Journals Online (AJOL)

    Objective: To establish whether inter-examiner variability is still a significant factor for the undergraduate orthopaedic clinical ... D. The scores for each student were tabulated and the range, mean, and pass rate determined for each of the examiners. ... has not the heart to reject the man”, consistently gave higher scores (1).

  8. Technological Capability's Predictor Variables

    Directory of Open Access Journals (Sweden)

    Fernanda Maciel Reichert

    2011-03-01

    Full Text Available The aim of this study was to identify the factors that influence in configuration of the technological capability of companies in sectors with medium-low technological intensity. To achieve the goal proposed in this article a survey was carried out. Based on the framework developed by Lall (1992 which classifies firms in basic, intermediate and advanced level of technological capability; it was found that the predominant technological capability is intermediate, with 83.7% of respondent companies (plastics companies in Brazil. It is believed that the main contribution of this study is the finding that the dependent variable named “Technological Capability” can be explained at a rate of 65% by six variables: development of new processes; selection of the best equipment supplier; sales of internally developed new technology to third parties; design and manufacture of equipment; study of the work methods and perform inventory control; and improvement of product quality.

  9. A meta analysis of the variability in firm performance attributable to human resource variables

    Directory of Open Access Journals (Sweden)

    Lloyd Kapondoro

    2015-01-01

    Full Text Available The contribution of Human Resource Management (HRM practices to organisation-wide performance is a critical aspect of the Human Resource (HR value proposition. The purpose of the study was to describe the strength of HRM practices and systems in influencing overall organisational performance. While research has concluded that there is a significant positive relationship between HRM practices or systems and an organisation’s market performance, the strength of this relationship has relatively not received much analysis in order to explain the degree to which HRM practices explain variance in firm performance. The study undertook a meta-analysis of published researches in international journals. The study established that HRM variables accounted for an average of 31% of the variability in firm performance. Cohen’s f2 calculated for this study as a meta effect size calculation yielded an average of 0.681, implying that HRM variables account for 68% of variability in firm performance. A one sample Kolmogorov-Smirnov test showed that the distribution of R2 is not normal. A major managerial implication of this study is that effective HRM practices have a significant business case. The study provides, quantitatively, the average variability in firm success that HRM accounts for.

  10. Heart rate variability in newborns.

    Science.gov (United States)

    Javorka, K; Lehotska, Z; Kozar, M; Uhrikova, Z; Kolarovszki, B; Javorka, M; Zibolen, M

    2017-09-22

    Heart rate (HR) and heart rate variability (HRV) in newborns is influenced by genetic determinants, gestational and postnatal age, and other variables. Premature infants have a reduced HRV. In neonatal HRV evaluated by spectral analysis, a dominant activity can be found in low frequency (LF) band (combined parasympathetic and sympathetic component). During the first postnatal days the activity in the high frequency (HF) band (parasympathetic component) rises, together with an increase in LF band and total HRV. Hypotrophy in newborn can cause less mature autonomic cardiac control with a higher contribution of sympathetic activity to HRV as demonstrated by sequence plot analysis. During quiet sleep (QS) in newborns HF oscillations increase - a phenomenon less expressed or missing in premature infants. In active sleep (AS), HRV is enhanced in contrast to reduced activity in HF band due to the rise of spectral activity in LF band. Comparison of the HR and HRV in newborns born by physiological vaginal delivery, without (VD) and with epidural anesthesia (EDA) and via sectio cesarea (SC) showed no significant differences in HR and in HRV time domain parameters. Analysis in the frequency domain revealed, that the lowest sympathetic activity in chronotropic cardiac chronotropic regulation is in the VD group. Different neonatal pathological states can be associated with a reduction of HRV and an improvement in the health conditions is followed by changes in HRV what can be use as a possible prognostic marker. Examination of heart rate variability in neonatology can provide information on the maturity of the cardiac chronotropic regulation in early postnatal life, on postnatal adaptation and in pathological conditions about the potential dysregulation of cardiac function in newborns, especially in preterm infants.

  11. Topography significantly influencing low flows in snow-dominated watersheds

    Science.gov (United States)

    Li, Qiang; Wei, Xiaohua; Yang, Xin; Giles-Hansen, Krysta; Zhang, Mingfang; Liu, Wenfei

    2018-03-01

    Watershed topography plays an important role in determining the spatial heterogeneity of ecological, geomorphological, and hydrological processes. Few studies have quantified the role of topography in various flow variables. In this study, 28 watersheds with snow-dominated hydrological regimes were selected with daily flow records from 1989 to 1996. These watersheds are located in the Southern Interior of British Columbia, Canada, and range in size from 2.6 to 1780 km2. For each watershed, 22 topographic indices (TIs) were derived, including those commonly used in hydrology and other environmental fields. Flow variables include annual mean flow (Qmean), Q10 %, Q25 %, Q50 %, Q75 %, Q90 %, and annual minimum flow (Qmin), where Qx % is defined as the daily flow that occurred each year at a given percentage (x). Factor analysis (FA) was first adopted to exclude some redundant or repetitive TIs. Then, multiple linear regression models were employed to quantify the relative contributions of TIs to each flow variable in each year. Our results show that topography plays a more important role in low flows (flow magnitudes ≤ Q75 %) than high flows. However, the effects of TIs on different flow magnitudes are not consistent. Our analysis also determined five significant TIs: perimeter, slope length factor, surface area, openness, and terrain characterization index. These can be used to compare watersheds when low flow assessments are conducted, specifically in snow-dominated regions with the watershed size less than several thousand square kilometres.

  12. Variable collimator

    International Nuclear Information System (INIS)

    Richey, J.B.; McBride, T.R.; Covic, J.

    1979-01-01

    This invention describes an automatic variable collimator which controls the width and thickness of X-ray beams in X-ray diagnostic medical equipment, and which is particularly adapted for use with computerized axial tomographic scanners. A two-part collimator is provided which shapes an X-ray beam both prior to its entering an object subject to radiographic analysis and after the attenuated beam has passed through the object. Interposed between a source of radiation and the object subject to radiographic analysis is a first or source collimator. The source collimator causes the X-ray beam emitted by the source of radiation to be split into a plurality of generally rectangular shaped beams. Disposed within the source collimator is a movable aperture plate which may be used to selectively vary the thickness of the plurality of generally rectangular shaped beams transmitted through the source collimator. A second or receiver collimator is interposed between the object subject to radiographic analysis and a series of radiation detectors. The receiver collimator is disposed to receive the attenuated X-ray beams passing through the object subject to radiographic analysis. Located within the receiver collimator are a plurality of movable aperture plates adapted to be displaced relative to a plurality of fixed aperture plates for the purpose of varying the width and thickness of the attenuated X-ray beams transmitted through the object subject to radiographic analysis. The movable aperture plates of the source and receiver collimators are automatically controlled by circuitry which is provided to allow remote operation of the movable aperture plates

  13. Korean Conference on Several Complex Variables

    CERN Document Server

    Byun, Jisoo; Gaussier, Hervé; Hirachi, Kengo; Kim, Kang-Tae; Shcherbina, Nikolay

    2015-01-01

    This volume includes 28 chapters by authors who are leading researchers of the world describing many of the up-to-date aspects in the field of several complex variables (SCV). These contributions are based upon their presentations at the 10th Korean Conference on Several Complex Variables (KSCV10), held as a satellite conference to the International Congress of Mathematicians (ICM) 2014 in Seoul, Korea. SCV has been the term for multidimensional complex analysis, one of the central research areas in mathematics. Studies over time have revealed a variety of rich, intriguing, new knowledge in complex analysis and geometry of analytic spaces and holomorphic functions which were "hidden" in the case of complex dimension one. These new theories have significant intersections with algebraic geometry, differential geometry, partial differential equations, dynamics, functional analysis and operator theory, and sheaves and cohomology, as well as the traditional analysis of holomorphic functions in all dimensions. This...

  14. BLAZAR OPTICAL VARIABILITY IN THE PALOMAR-QUEST SURVEY

    International Nuclear Information System (INIS)

    Bauer, Anne; Baltay, Charles; Coppi, Paolo; Ellman, Nancy; Jerke, Jonathan; Rabinowitz, David; Scalzo, Richard

    2009-01-01

    We study the ensemble optical variability of 276 flat-spectrum radio quasars (FSRQs) and 86 BL Lacs in the Palomar-QUEST Survey with the goal of searching for common fluctuation properties, examining the range of behavior across the sample, and characterizing the appearance of blazars in such a survey so that future work can more easily identify such objects. The survey, which covers 15,000 deg 2 multiple times over 3.5 years, allows for the first ensemble blazar study of this scale. Variability amplitude distributions are shown for the FSRQ and BL Lac samples for numerous time lags, and also studied through structure function analyses. Individual blazars show a wide range of variability amplitudes, timescales, and duty cycles. Of the best-sampled objects, 35% are seen to vary by more than 0.4 mag; for these, the fraction of measurements contributing to the high-amplitude variability ranges constantly from about 5% to 80%. Blazar variability has some similarities to that of type I quasi-stellar objects (QSOs) but includes larger amplitude fluctuations on all timescales. FSRQ variability amplitudes are particularly similar to those of QSOs on timescales of several months, suggesting significant contributions from the accretion disk to the variable flux at these timescales. Optical variability amplitudes are correlated with the maximum apparent velocities of the radio jet for the subset of FSRQs with MOJAVE Very Long Baseline Array measurements, implying that the optically variable flux's strength is typically related to that of the radio emission. We also study CRATES radio-selected FSRQ candidates, which show similar variability characteristics to known FSRQs; this suggests a high purity for the CRATES sample.

  15. Spatial and temporal variability in urban fine particulate matter concentrations

    International Nuclear Information System (INIS)

    Levy, Jonathan I.; Hanna, Steven R.

    2011-01-01

    Identification of hot spots for urban fine particulate matter (PM 2.5 ) concentrations is complicated by the significant contributions from regional atmospheric transport and the dependence of spatial and temporal variability on averaging time. We focus on PM 2.5 patterns in New York City, which includes significant local sources, street canyons, and upwind contributions to concentrations. A literature synthesis demonstrates that long-term (e.g., one-year) average PM 2.5 concentrations at a small number of widely-distributed monitoring sites would not show substantial variability, whereas short-term (e.g., 1-h) average measurements with high spatial density would show significant variability. Statistical analyses of ambient monitoring data as a function of wind speed and direction reinforce the significance of regional transport but show evidence of local contributions. We conclude that current monitor siting may not adequately capture PM 2.5 variability in an urban area, especially in a mega-city, reinforcing the necessity of dispersion modeling and methods for analyzing high-resolution monitoring observations. - Highlights: →Fine particulate matter (PM 2.5 ) hot spots are hard to identify in urban areas. → Literature conclusions about PM 2.5 hot spots depend on study design and methods. → Hot spots are more likely for short-term concentrations at high spatial density. → Statistical methods illustrate local source impacts beyond regional transport. → Dispersion models and high-resolution monitors are both needed to find hot spots. - Fine particulate matter can vary spatially within large urban areas, in spite of the significant contribution from regional atmospheric transport.

  16. Statistically significant relational data mining :

    Energy Technology Data Exchange (ETDEWEB)

    Berry, Jonathan W.; Leung, Vitus Joseph; Phillips, Cynthia Ann; Pinar, Ali; Robinson, David Gerald; Berger-Wolf, Tanya; Bhowmick, Sanjukta; Casleton, Emily; Kaiser, Mark; Nordman, Daniel J.; Wilson, Alyson G.

    2014-02-01

    This report summarizes the work performed under the project (3z(BStatitically significant relational data mining.(3y (BThe goal of the project was to add more statistical rigor to the fairly ad hoc area of data mining on graphs. Our goal was to develop better algorithms and better ways to evaluate algorithm quality. We concetrated on algorithms for community detection, approximate pattern matching, and graph similarity measures. Approximate pattern matching involves finding an instance of a relatively small pattern, expressed with tolerance, in a large graph of data observed with uncertainty. This report gathers the abstracts and references for the eight refereed publications that have appeared as part of this work. We then archive three pieces of research that have not yet been published. The first is theoretical and experimental evidence that a popular statistical measure for comparison of community assignments favors over-resolved communities over approximations to a ground truth. The second are statistically motivated methods for measuring the quality of an approximate match of a small pattern in a large graph. The third is a new probabilistic random graph model. Statisticians favor these models for graph analysis. The new local structure graph model overcomes some of the issues with popular models such as exponential random graph models and latent variable models.

  17. Determining Semantically Related Significant Genes.

    Science.gov (United States)

    Taha, Kamal

    2014-01-01

    GO relation embodies some aspects of existence dependency. If GO term xis existence-dependent on GO term y, the presence of y implies the presence of x. Therefore, the genes annotated with the function of the GO term y are usually functionally and semantically related to the genes annotated with the function of the GO term x. A large number of gene set enrichment analysis methods have been developed in recent years for analyzing gene sets enrichment. However, most of these methods overlook the structural dependencies between GO terms in GO graph by not considering the concept of existence dependency. We propose in this paper a biological search engine called RSGSearch that identifies enriched sets of genes annotated with different functions using the concept of existence dependency. We observe that GO term xcannot be existence-dependent on GO term y, if x- and y- have the same specificity (biological characteristics). After encoding into a numeric format the contributions of GO terms annotating target genes to the semantics of their lowest common ancestors (LCAs), RSGSearch uses microarray experiment to identify the most significant LCA that annotates the result genes. We evaluated RSGSearch experimentally and compared it with five gene set enrichment systems. Results showed marked improvement.

  18. The energetic significance of cooking.

    Science.gov (United States)

    Carmody, Rachel N; Wrangham, Richard W

    2009-10-01

    While cooking has long been argued to improve the diet, the nature of the improvement has not been well defined. As a result, the evolutionary significance of cooking has variously been proposed as being substantial or relatively trivial. In this paper, we evaluate the hypothesis that an important and consistent effect of cooking food is a rise in its net energy value. The pathways by which cooking influences net energy value differ for starch, protein, and lipid, and we therefore consider plant and animal foods separately. Evidence of compromised physiological performance among individuals on raw diets supports the hypothesis that cooked diets tend to provide energy. Mechanisms contributing to energy being gained from cooking include increased digestibility of starch and protein, reduced costs of digestion for cooked versus raw meat, and reduced energetic costs of detoxification and defence against pathogens. If cooking consistently improves the energetic value of foods through such mechanisms, its evolutionary impact depends partly on the relative energetic benefits of non-thermal processing methods used prior to cooking. We suggest that if non-thermal processing methods such as pounding were used by Lower Palaeolithic Homo, they likely provided an important increase in energy gain over unprocessed raw diets. However, cooking has critical effects not easily achievable by non-thermal processing, including the relatively complete gelatinisation of starch, efficient denaturing of proteins, and killing of food borne pathogens. This means that however sophisticated the non-thermal processing methods were, cooking would have conferred incremental energetic benefits. While much remains to be discovered, we conclude that the adoption of cooking would have led to an important rise in energy availability. For this reason, we predict that cooking had substantial evolutionary significance.

  19. Biological Sampling Variability Study

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-08

    There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

  20. Variability in perceived satisfaction of reservoir management objectives

    Science.gov (United States)

    Owen, W.J.; Gates, T.K.; Flug, M.

    1997-01-01

    Fuzzy set theory provides a useful model to address imprecision in interpreting linguistically described objectives for reservoir management. Fuzzy membership functions can be used to represent degrees of objective satisfaction for different values of management variables. However, lack of background information, differing experiences and qualifications, and complex interactions of influencing factors can contribute to significant variability among membership functions derived from surveys of multiple experts. In the present study, probabilistic membership functions are used to model variability in experts' perceptions of satisfaction of objectives for hydropower generation, fish habitat, kayaking, rafting, and scenery preservation on the Green River through operations of Flaming Gorge Dam. Degree of variability in experts' perceptions differed among objectives but resulted in substantial uncertainty in estimation of optimal reservoir releases.

  1. Variability of the raindrop size distribution at small spatial scales

    Science.gov (United States)

    Berne, A.; Jaffrain, J.

    2010-12-01

    Because of the interactions between atmospheric turbulence and cloud microphysics, the raindrop size distribution (DSD) is strongly variable in space and time. The spatial variability of the DSD at small spatial scales (below a few km) is not well documented and not well understood, mainly because of a lack of adequate measurements at the appropriate resolutions. A network of 16 disdrometers (Parsivels) has been designed and set up over EPFL campus in Lausanne, Switzerland. This network covers a typical operational weather radar pixel of 1x1 km2. The question of the significance of the variability of the DSD at such small scales is relevant for radar remote sensing of rainfall because the DSD is often assumed to be uniform within a radar sample volume and because the Z-R relationships used to convert the measured radar reflectivity Z into rain rate R are usually derived from point measurements. Thanks to the number of disdrometers, it was possible to quantify the spatial variability of the DSD at the radar pixel scale and to show that it can be significant. In this contribution, we show that the variability of the total drop concentration, of the median volume diameter and of the rain rate are significant, taking into account the sampling uncertainty associated with disdrometer measurements. The influence of this variability on the Z-R relationship can be non-negligible. Finally, the spatial structure of the DSD is quantified using a geostatistical tool, the variogram, and indicates high spatial correlation within a radar pixel.

  2. Contribution to the characterization of 222-radon concentrations variability in water to the understanding of an aquifer behaviour in fractured medium: example of the Ploemeur site, Morbihan; Apport de la caracterisation de la variabilite des concentrations en radon-222 dans l'eau a la comprehension du fonctionnement d'un aquifere en milieu fracture de socle: exemple du site de Ploemeur, Morbihan

    Energy Technology Data Exchange (ETDEWEB)

    Le Druillennec, Th

    2007-06-15

    Heterogeneous fractured aquifers which developed in crystalline rocks, such as schist or granite, supply 20% of tap water production of Brittany. These fractured media present a large range of permeability. In these aquifers, fluid flow and transport of elements dissolved in water are strongly related on the geometry of the fractured network. Increasing the knowledge of the hydrogeological behaviour of the aquifer is fundamental for the management and the protection of the groundwater resources. Radon-222 is a radioactive noble gas produced from radium-226 further to the radioactive decay of uranium-238; it occurs naturally in ground waters and derives primarily from U-rich rocks and minerals that have been in contact with water. Radon-222 concentrations in waters are liable to provide significant and relevant information on both the geometry of a fracture network and the flow distribution. Furthermore, radon may also be used as a tracer in the aquifer of water exchanges between zones of variable permeability. Three main results were obtained in this study: 1. An accurate characterisation of the radon concentrations in water was carried out in the Ploemeur aquifer (Brittany, France). These results highlight the variability in the spatial and vertical distributions of {sup 222}Rn activity in groundwater together with a wide range of concentrations extending from 0 to 1 500 Bq.L{sup -1}. 2. The influence of fracture aperture on radon content in groundwater has been demonstrated with the modelling of radon concentration. Indeed, the satisfactory results obtained with a simple crack model highlight that the geometry of the fracture network controls the radon activity in groundwater. 3. Thus, the results of pumping tests performed in the boreholes improved our understanding of the system. After the pumping test, an increase of the radon content in groundwater occurred and evidenced a contribution of a radon-rich water to supply the flow rate that seems to come from the

  3. The contribution of the Saudi woman in economic development

    Directory of Open Access Journals (Sweden)

    Haga Elimam

    2014-09-01

    Full Text Available The main purpose of the study is to analyze the contribution of Saudi woman in economic development of the country. This report develops an understanding of women contributions towards economic development. The method used to analyze the data was Pearson correlation. Through correlation we can determine the relationship between the variables. The study was a quantitative study. The data for five years was taken. Hypotheses development proceeded by focusing on labor work force participation, literacy rate of adult females and GDP rate within Saudi Arabia. Analysis was done on the results and the findings confirmed that there is a significant relationship between the variables. This study was of exploratory nature, it is recommended that this research be expanded to a statistically valid base within Saudi Arabia and then expand the study to additional countries. The findings showed that there was a high significant relationship between women labor work force participation and GDP. Whereas, there was moderate significant relationship between labor work force and literacy rate. Hence, there is a positive relationship between women contribution and economic development. The research is conducted within the context of Saudi Arabia and has certain limitation with further directions of conducting research in related field to get more accurate results.

  4. Variability in human body size

    Science.gov (United States)

    Annis, J. F.

    1978-01-01

    The range of variability found among homogeneous groups is described and illustrated. Those trends that show significantly marked differences between sexes and among a number of racial/ethnic groups are also presented. Causes of human-body size variability discussed include genetic endowment, aging, nutrition, protective garments, and occupation. The information is presented to aid design engineers of space flight hardware and equipment.

  5. Sex as a Biological Variable: Who, What, When, Why, and How.

    Science.gov (United States)

    Bale, Tracy L; Epperson, C Neill

    2017-01-01

    The inclusion of sex as a biological variable in research is absolutely essential for improving our understanding of disease mechanisms contributing to risk and resilience. Studies focusing on examining sex differences have demonstrated across many levels of analyses and stages of brain development and maturation that males and females can differ significantly. This review will discuss examples of animal models and clinical studies to provide guidance and reference for the inclusion of sex as an important biological variable relevant to a Neuropsychopharmacology audience.

  6. Benchmarking Variable Selection in QSAR.

    Science.gov (United States)

    Eklund, Martin; Norinder, Ulf; Boyer, Scott; Carlsson, Lars

    2012-02-01

    Variable selection is important in QSAR modeling since it can improve model performance and transparency, as well as reduce the computational cost of model fitting and predictions. Which variable selection methods that perform well in QSAR settings is largely unknown. To address this question we, in a total of 1728 benchmarking experiments, rigorously investigated how eight variable selection methods affect the predictive performance and transparency of random forest models fitted to seven QSAR datasets covering different endpoints, descriptors sets, types of response variables, and number of chemical compounds. The results show that univariate variable selection methods are suboptimal and that the number of variables in the benchmarked datasets can be reduced with about 60 % without significant loss in model performance when using multivariate adaptive regression splines MARS and forward selection. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Solar Variability and Planetary Climates

    CERN Document Server

    Calisesi, Y; Gray, L; Langen, J; Lockwood, M

    2007-01-01

    Variations in solar activity, as revealed by variations in the number of sunspots, have been observed since ancient times. To what extent changes in the solar output may affect planetary climates, though, remains today more than ever a subject of controversy. In 2000, the SSSI volume on Solar Variability and Climate reviewed the to-date understanding of the physics of solar variability and of the associated climate response. The present volume on Solar Variability and Planetary Climates provides an overview of recent advances in this field, with particular focus at the Earth's middle and lower atmosphere. The book structure mirrors that of the ISSI workshop held in Bern in June 2005, the collection of invited workshop contributions and of complementary introductory papers synthesizing the current understanding in key research areas such as middle atmospheric processes, stratosphere-troposphere dynamical coupling, tropospheric aerosols chemistry, solar storm influences, solar variability physics, and terrestri...

  8. The radioecological significance of semi-natural ecosystems

    International Nuclear Information System (INIS)

    Howard, B.J.; Howard, D.C.

    1997-01-01

    The transfer of radiocaesium to many food products either produced in or harvested from semi-natural ecosystems is high compared with intensive agricultural areas. Radiocaesium contamination levels in semi-natural foods are highly variable and difficult to predict. Spatial analysis may help to explain some of the variability and give improved estimates of the total output of radiocaesium in food products produced or harvested from semi-natural ecosystems. Consumption of foodstuffs from semi-natural ecosystems can contribute significantly to radiocaesium ingestion by humans. The long effective half-lives that occur for some semi-natural products lead to an increase with time in their importance compared with agricultural products. In determining the importance of semi-natural food products, the diet needs to be considered for both the average population and for special groups who utilize these environments to a greater extent than normal. Effective countermeasures have been developed to reduce radiocaesium levels in some semi-natural products. (author)

  9. Articulatory variability in cluttering.

    Science.gov (United States)

    Hartinger, Mariam; Mooshammer, Christine

    2008-01-01

    In order to investigate the articulatory processes of the hasty and mumbled speech in cluttering, the kinematic variability was analysed by means of electromagnetic midsagittal articulography. In contrast to persons with stuttering, those with cluttering improve their intelligibility by concentrating on their speech task. Variability has always been an important criterion in comparable studies of stuttering and is discussed in terms of the stability of the speech motor system. The aim of the current study was to analyse the spatial and temporal variability in the speech of three persons with cluttering (PWC) and three control speakers. All participants were native speakers of German. The speech material consisted of repetitive CV syllables and loan words such as 'emotionalisieren', because PWC have the severest problems with long words with a complex syllable structure. The results showed a significantly higher coefficient of variation for PWC in loan word production, both in the temporal and in the spatial domain, whereas the means of displacements and durations did not differ between groups. These findings were discussed in terms of the effects of the linguistic complexity, since for the syllable repetition task, no significant differences between PWC and controls were found. Copyright 2008 S. Karger AG, Basel.

  10. Decomposing global crop yield variability

    Science.gov (United States)

    Ben-Ari, Tamara; Makowski, David

    2014-11-01

    Recent food crises have highlighted the need to better understand the between-year variability of agricultural production. Although increasing future production seems necessary, the globalization of commodity markets suggests that the food system would also benefit from enhanced supplies stability through a reduction in the year-to-year variability. Here, we develop an analytical expression decomposing global crop yield interannual variability into three informative components that quantify how evenly are croplands distributed in the world, the proportion of cultivated areas allocated to regions of above or below average variability and the covariation between yields in distinct world regions. This decomposition is used to identify drivers of interannual yield variations for four major crops (i.e., maize, rice, soybean and wheat) over the period 1961-2012. We show that maize production is fairly spread but marked by one prominent region with high levels of crop yield interannual variability (which encompasses the North American corn belt in the USA, and Canada). In contrast, global rice yields have a small variability because, although spatially concentrated, much of the production is located in regions of below-average variability (i.e., South, Eastern and South Eastern Asia). Because of these contrasted land use allocations, an even cultivated land distribution across regions would reduce global maize yield variance, but increase the variance of global yield rice. Intermediate results are obtained for soybean and wheat for which croplands are mainly located in regions with close-to-average variability. At the scale of large world regions, we find that covariances of regional yields have a negligible contribution to global yield variance. The proposed decomposition could be applied at any spatial and time scales, including the yearly time step. By addressing global crop production stability (or lack thereof) our results contribute to the understanding of a key

  11. Discovering the Significance of Scientific Design Practice

    DEFF Research Database (Denmark)

    Pries-Heje, Jan; Baskerville, Richard

    2016-01-01

    This paper discusses and defines the achievement of significance in design science research. We review the values and processes of old-science and how this mode of science attacks the complexity of scientific knowledge production through analysis. We then explain how new-science attacks...... the complexity of scientific knowledge production through synthesis. The work argues that significance of the new-science contribution in design science can be obfuscated when wrapped in old-science. This understanding helps reveal how new-science, such as design science research, constitutes its significance...

  12. Tides and Decadal Variability

    Science.gov (United States)

    Ray, Richard D.

    2003-01-01

    This paper reviews the mechanisms by which oceanic tides and decadal variability in the oceans are connected. We distinguish between variability caused by tides and variability observed in the tides themselves. Both effects have been detected at some level. The most obvious connection with decadal timescales is through the 18.6-year precession of the moon's orbit plane. This precession gives rise to a small tide of the same period and to 18.6-year modulations in the phase and amplitudes of short-period tides. The 18.6-year "node tide" is very small, no more than 2 cm anywhere, and in sea level data it is dominated by the ocean's natural Variability. Some authors have naively attributed climate variations with periods near 19 years directly to the node tide, but the amplitude of the tide is too small for this mechanism to be operative. The more likely explanation (Loder and Garrett, JGR, 83, 1967-70, 1978) is that the 18.6-y modulations in short-period tides, especially h e principal tide M2, cause variations in ocean mixing, which is then observed in temperature and other climatic indicators. Tidally forced variability has also been proposed by some authors, either in response to occasional (and highly predictable) tidal extremes or as a nonlinear low-frequency oscillation caused by interactions between short-period tides. The former mechanism can produce only short-duration events hardly more significant than normal tidal ranges, but the latter mechanism can in principle induce low-frequency oscillations. The most recent proposal of this type is by Keeling and Whorf, who highlight the 1800-year spectral peak discovered by Bond et al. (1997). But the proposal appears contrived and should be considered, in the words of Munk et al. (2002), "as the most likely among unlikely candidates."

  13. A contribution Monte Carlo method

    International Nuclear Information System (INIS)

    Aboughantous, C.H.

    1994-01-01

    A Contribution Monte Carlo method is developed and successfully applied to a sample deep-penetration shielding problem. The random walk is simulated in most of its parts as in conventional Monte Carlo methods. The probability density functions (pdf's) are expressed in terms of spherical harmonics and are continuous functions in direction cosine and azimuthal angle variables as well as in position coordinates; the energy is discretized in the multigroup approximation. The transport pdf is an unusual exponential kernel strongly dependent on the incident and emergent directions and energies and on the position of the collision site. The method produces the same results obtained with the deterministic method with a very small standard deviation, with as little as 1,000 Contribution particles in both analog and nonabsorption biasing modes and with only a few minutes CPU time

  14. Simple models to predict grassland ecosystem C exchange and actual evapotranspiration using NDVI and environmental variables

    Science.gov (United States)

    Semiarid grasslands contribute significantly to net terrestrial carbon flux as plant productivity and heterotrophic respiration in these moisture-limited systems are correlated with metrics related to water availability (e.g., precipitation, Actual EvapoTranspiration or AET). These variables are als...

  15. Deep Ocean Contribution to Sea Level Rise

    Science.gov (United States)

    Chang, L.; Sun, W.; Tang, H.; Wang, Q.

    2017-12-01

    The ocean temperature and salinity change in the upper 2000m can be detected by Argo floats, so we can know the steric height change of the ocean. But the ocean layers above 2000m represent only 50% of the total ocean volume. Although the temperature and salinity change are small compared to the upper ocean, the deep ocean contribution to sea level might be significant because of its large volume. There has been some research on the deep ocean rely on the very sparse situ observation and are limited to decadal and longer-term rates of change. The available observational data in the deep ocean are too spares to determine the temporal variability, and the long-term changes may have a bias. We will use the Argo date and combine the situ data and topographic data to estimate the temperature and salinity of the sea water below 2000m, so we can obtain a monthly data. We will analyze the seasonal and annual change of the steric height change due to the deep ocean between 2005 and 2016. And we will evaluate the result combination the present-day satellite and in situ observing systems. The deep ocean contribution can be inferred indirectly as the difference between the altimetry minus GRACE and Argo-based steric sea level.

  16. Combining clinical variables to optimize prediction of antidepressant treatment outcomes.

    Science.gov (United States)

    Iniesta, Raquel; Malki, Karim; Maier, Wolfgang; Rietschel, Marcella; Mors, Ole; Hauser, Joanna; Henigsberg, Neven; Dernovsek, Mojca Zvezdana; Souery, Daniel; Stahl, Daniel; Dobson, Richard; Aitchison, Katherine J; Farmer, Anne; Lewis, Cathryn M; McGuffin, Peter; Uher, Rudolf

    2016-07-01

    The outcome of treatment with antidepressants varies markedly across people with the same diagnosis. A clinically significant prediction of outcomes could spare the frustration of trial and error approach and improve the outcomes of major depressive disorder through individualized treatment selection. It is likely that a combination of multiple predictors is needed to achieve such prediction. We used elastic net regularized regression to optimize prediction of symptom improvement and remission during treatment with escitalopram or nortriptyline and to identify contributing predictors from a range of demographic and clinical variables in 793 adults with major depressive disorder. A combination of demographic and clinical variables, with strong contributions from symptoms of depressed mood, reduced interest, decreased activity, indecisiveness, pessimism and anxiety significantly predicted treatment outcomes, explaining 5-10% of variance in symptom improvement with escitalopram. Similar combinations of variables predicted remission with area under the curve 0.72, explaining approximately 15% of variance (pseudo R(2)) in who achieves remission, with strong contributions from body mass index, appetite, interest-activity symptom dimension and anxious-somatizing depression subtype. Escitalopram-specific outcome prediction was more accurate than generic outcome prediction, and reached effect sizes that were near or above a previously established benchmark for clinical significance. Outcome prediction on the nortriptyline arm did not significantly differ from chance. These results suggest that easily obtained demographic and clinical variables can predict therapeutic response to escitalopram with clinically meaningful accuracy, suggesting a potential for individualized prescription of this antidepressant drug. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. What variables can influence clinical reasoning?

    Directory of Open Access Journals (Sweden)

    Vahid Ashoorion

    2012-01-01

    Full Text Available Background: Clinical reasoning is one of the most important competencies that a physician should achieve. Many medical schools and licensing bodies try to predict it based on some general measures such as critical thinking, personality, and emotional intelligence. This study aimed at providing a model to design the relationship between the constructs. Materials and Methods: Sixty-nine medical students participated in this study. A battery test devised that consist four parts: Clinical reasoning measures, personality NEO inventory, Bar-On EQ inventory, and California critical thinking questionnaire. All participants completed the tests. Correlation and multiple regression analysis consumed for data analysis. Results: There is low to moderate correlations between clinical reasoning and other variables. Emotional intelligence is the only variable that contributes clinical reasoning construct (r=0.17-0.34 (R 2 chnage = 0.46, P Value = 0.000. Conclusion: Although, clinical reasoning can be considered as a kind of thinking, no significant correlation detected between it and other constructs. Emotional intelligence (and its subscales is the only variable that can be used for clinical reasoning prediction.

  18. What variables can influence clinical reasoning?

    Science.gov (United States)

    Ashoorion, Vahid; Liaghatdar, Mohammad Javad; Adibi, Peyman

    2012-12-01

    Clinical reasoning is one of the most important competencies that a physician should achieve. Many medical schools and licensing bodies try to predict it based on some general measures such as critical thinking, personality, and emotional intelligence. This study aimed at providing a model to design the relationship between the constructs. Sixty-nine medical students participated in this study. A battery test devised that consist four parts: Clinical reasoning measures, personality NEO inventory, Bar-On EQ inventory, and California critical thinking questionnaire. All participants completed the tests. Correlation and multiple regression analysis consumed for data analysis. There is low to moderate correlations between clinical reasoning and other variables. Emotional intelligence is the only variable that contributes clinical reasoning construct (r=0.17-0.34) (R(2) chnage = 0.46, P Value = 0.000). Although, clinical reasoning can be considered as a kind of thinking, no significant correlation detected between it and other constructs. Emotional intelligence (and its subscales) is the only variable that can be used for clinical reasoning prediction.

  19. Hypocretin measurement: shelf age of radioimmunoassay kit, but not freezer time, influences assay variability.

    Science.gov (United States)

    Keating, Glenda; Bliwise, Donald L; Saini, Prabhjyot; Rye, David B; Trotti, Lynn Marie

    2017-09-01

    The hypothalamic peptide hypocretin 1 (orexin A) may be assayed in cerebrospinal fluid to diagnose narcolepsy type 1. This testing is not commercially available, and factors contributing to assay variability have not previously been comprehensively explored. In the present study, cerebrospinal fluid hypocretin concentrations were determined in duplicate in 155 patient samples, across a range of sleep disorders. Intra-assay variability of these measures was analyzed. Inter-assay correlation between samples tested at Emory and at Stanford was high (r = 0.79, p hypocretin values, such that kits closer to expiration exhibit significantly more variability.

  20. Ergonomics Contribution in Maintainability

    Science.gov (United States)

    Teymourian, Kiumars; Seneviratne, Dammika; Galar, Diego

    2017-09-01

    The objective of this paper is to describe an ergonomics contribution in maintainability. The economical designs, inputs and training helps to increase the maintainability indicators for industrial devices. This analysis can be helpful, among other cases, to compare systems, to achieve a better design regarding maintainability requirements, to improve this maintainability under specific industrial environment and to foresee maintainability problems due to eventual changes in a device operation conditions. With this purpose, this work first introduces the notion of ergonomics and human factors, maintainability and the implementation of assessment of human postures, including some important postures to perform maintenance activities. A simulation approach is used to identify the critical posture of the maintenance personnel and implements the defined postures with minimal loads on the personnel who use the equipment in a practical scenario. The simulation inputs are given to the designers to improve the workplace/equipment in order to high level of maintainability. Finally, the work concludes summarizing the more significant aspects and suggesting future research.

  1. It's the People, Stupid: The Role of Personality and Situational Variable in Predicting Decisionmaker Behavior

    National Research Council Canada - National Science Library

    Sticha, Paul J; Buede, Dennis M; Rees, Richard L

    2006-01-01

    .... to identity assumptions and determinant variables, and to quantify each variable's relative contribution to the prediction, producing a graphical representation of the analysis with explicit levels of uncertainty...

  2. Major contributions to science

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Andre

    1991-03-15

    It may look difficult to describe the scientific contributions of Léon Van Hove, who started his career as a pure mathematician, and then a mathematical physicist, and ended it as a phenomenologist and an adseveral of Léon's students, in particular N. Hugenholtz. In this domain, his contributions were numerous and fundamental.

  3. Major contributions to science

    International Nuclear Information System (INIS)

    Martin, Andre

    1991-01-01

    It may look difficult to describe the scientific contributions of Léon Van Hove, who started his career as a pure mathematician, and then a mathematical physicist, and ended it as a phenomenologist and an adseveral of Léon's students, in particular N. Hugenholtz. In this domain, his contributions were numerous and fundamental

  4. Variable importance in latent variable regression models

    NARCIS (Netherlands)

    Kvalheim, O.M.; Arneberg, R.; Bleie, O.; Rajalahti, T.; Smilde, A.K.; Westerhuis, J.A.

    2014-01-01

    The quality and practical usefulness of a regression model are a function of both interpretability and prediction performance. This work presents some new graphical tools for improved interpretation of latent variable regression models that can also assist in improved algorithms for variable

  5. Cognitive factors contributing to spelling performance in children with prenatal alcohol exposure.

    Science.gov (United States)

    Glass, Leila; Graham, Diana M; Akshoomoff, Natacha; Mattson, Sarah N

    2015-11-01

    Heavy prenatal alcohol exposure is associated with impaired school functioning. Spelling performance has not been comprehensively evaluated. We examined whether children with heavy prenatal alcohol exposure demonstrate deficits in spelling and related abilities, including reading, and tested whether there are unique underlying mechanisms for observed deficits in this population. Ninety-six school-age children made up 2 groups: children with heavy prenatal alcohol exposure (AE, n = 49) and control children (CON, n = 47). Children completed select subtests from the Wechsler Individual Achievement Test-Second Edition and the NEPSY-II. Group differences and relations between spelling and theoretically related cognitive variables were evaluated using multivariate analysis of variance and Pearson correlations. Hierarchical regression analyses were used to assess contributions of group membership and cognitive variables to spelling performance. The specificity of these deficits and underlying mechanisms was tested by examining the relations between reading ability, group membership, and cognitive variables. Groups differed significantly on all variables. Group membership and phonological processing significantly contributed to spelling performance, whereas for reading, group membership and all cognitive variables contributed significantly. For both reading and spelling, group × working memory interactions revealed that working memory contributed independently only for alcohol-exposed children. Alcohol-exposed children demonstrated a unique pattern of spelling deficits. The relation of working memory to spelling and reading was specific to the AE group, suggesting that if prenatal alcohol exposure is known or suspected, working memory ability should be considered in the development and implementation of explicit instruction. (c) 2015 APA, all rights reserved).

  6. Personal and situational variables, and career concerns: predicting career adaptability in young adults.

    Science.gov (United States)

    Yousefi, Zahra; Abedi, Mohammadreza; Baghban, Iran; Eatemadi, Ozra; Abedi, Ahmade

    2011-05-01

    This study examined relationships among career adaptability and career concerns, social support and goal orientation. We surveyed 304 university students using measures of career concerns, adaptability (career planning, career exploration, self-exploration, decision-making, self-regulation), goal-orientation (learning, performance-prove, performance-avoid) and social support (family, friends, significant others). Multiple regression analysis revealed career concerns, learning and performance-prove goal orientations emerged relatively as the most important contributors. Other variables did not contribute significantly.

  7. Summaries of poster contributions

    International Nuclear Information System (INIS)

    1981-01-01

    The 10. meeting covered subjects on the application of electron microscopy in numerous fields such as biology and medicine, solid state physics, semiconductor research and production, crystallography, materials science, and chemistry of polymers. 174 summaries of poster contributions are included

  8. Historical Significant Volcanic Eruption Locations

    Data.gov (United States)

    Department of Homeland Security — A significant eruption is classified as one that meets at least one of the following criteriacaused fatalities, caused moderate damage (approximately $1 million or...

  9. Understanding Solar Cycle Variability

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, R. H.; Schüssler, M., E-mail: cameron@mps.mpg.de [Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany)

    2017-07-10

    The level of solar magnetic activity, as exemplified by the number of sunspots and by energetic events in the corona, varies on a wide range of timescales. Most prominent is the 11-year solar cycle, which is significantly modulated on longer timescales. Drawing from dynamo theory, together with the empirical results of past solar activity and similar phenomena for solar-like stars, we show that the variability of the solar cycle can be essentially understood in terms of a weakly nonlinear limit cycle affected by random noise. In contrast to ad hoc “toy models” for the solar cycle, this leads to a generic normal-form model, whose parameters are all constrained by observations. The model reproduces the characteristics of the variable solar activity on timescales between decades and millennia, including the occurrence and statistics of extended periods of very low activity (grand minima). Comparison with results obtained with a Babcock–Leighton-type dynamo model confirm the validity of the normal-mode approach.

  10. Significance of ISO 9000 Quality Management System for ...

    African Journals Online (AJOL)

    Significance of ISO 9000 Quality Management System for Performance ... of ISO 9000 Quality Management System implementation for performance improvement. ... to find out the relationship between certification and process variability.

  11. Significant events caused by extraneous acts

    International Nuclear Information System (INIS)

    Verlaeken, J.

    1987-01-01

    The operating experience feedback system of VINCOTTE, called ARIANE, consists, among others, of preparing synthesis reports on specific safety concerns. A recent report deals with significant events caused by extranous acts. Events attributable to human error are numerous. Confusion errors have already been analysed in several publications (NES IRS 664 etc.). However, are described here some ten incidents where extranous acts occurred: ZION 2 (September 76), OYSTER CREEK (May 79), PALISADES (January 81), CATAWBA (August 85), etc. The contributing factors for these unfortunate initiatives are explained; several resort to psychological influences. Corrective actions are discussed, and some general lessons are drawn. (author)

  12. Significant exposures to isoeugenol derivaties in perfumes

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Johansen, Jeanne Duus

    2008-01-01

    in perfumes/aftershaves. MATERIALS AND METHODS: 29 international brand perfumes/aftershaves were analysed for the target fragrance ingredient by gas chromatography-mass spectrometry. All samples were analysed in duplicate at detection levels of 1-5 p.p.m. RESULTS: 16 products (55%) contained isoeugenol...... was not detected in any of the investigated products. CONCLUSIONS: Isoeugenyl acetate is present in perfumes/aftershaves, in some products in significant amounts. This may lead to elicitation of contact allergy in isoeugenol-sensitized individuals and may contribute to unchanged levels of isoeugenol sensitization....

  13. Risk control and the minimum significant risk

    International Nuclear Information System (INIS)

    Seiler, F.A.; Alvarez, J.L.

    1996-01-01

    Risk management implies that the risk manager can, by his actions, exercise at least a modicum of control over the risk in question. In the terminology of control theory, a management action is a control signal imposed as feedback on the system to bring about a desired change in the state of the system. In the terminology of risk management, an action is taken to bring a predicted risk to lower values. Even if it is assumed that the management action taken is 100% effective and that the projected risk reduction is infinitely well known, there is a lower limit to the desired effects that can be achieved. It is based on the fact that all risks, such as the incidence of cancer, exhibit a degree of variability due to a number of extraneous factors such as age at exposure, sex, location, and some lifestyle parameters such as smoking or the consumption of alcohol. If the control signal is much smaller than the variability of the risk, the signal is lost in the noise and control is lost. This defines a minimum controllable risk based on the variability of the risk over the population considered. This quantity is the counterpart of the minimum significant risk which is defined by the uncertainties of the risk model. Both the minimum controllable risk and the minimum significant risk are evaluated for radiation carcinogenesis and are shown to be of the same order of magnitude. For a realistic management action, the assumptions of perfectly effective action and perfect model prediction made above have to be dropped, resulting in an effective minimum controllable risk which is determined by both risk limits. Any action below that effective limit is futile, but it is also unethical due to the ethical requirement of doing more good than harm. Finally, some implications of the effective minimum controllable risk on the use of the ALARA principle and on the evaluation of remedial action goals are presented

  14. Physical Design Factors Contributing to Patient Falls.

    Science.gov (United States)

    Pati, Debajyoti; Valipoor, Shabboo; Cloutier, Aimee; Yang, James; Freier, Patricia; Harvey, Thomas E; Lee, Jaehoon

    2017-02-03

    The aim of this study was to identify physical design elements that contribute to potential falls in patient rooms. An exploratory, physical simulation-based approach was adopted for the study. Twenty-seven subjects, older than 70 years (11 male and 16 female subjects), conducted scripted tasks in a mockup of a patient bathroom and clinician zone. Activities were captured using motion-capture technology and video recording. After biomechanical data processing, video clips associated with potential fall moments were extracted and then examined and coded by a group of registered nurses and health care designers. Exploratory analyses of the coded data were conducted followed by a series of multivariate analyses using regression models. In multivariate models with all personal, environmental, and postural variables, only the postural variables demonstrated statistical significance-turning, grabbing, pushing, and pulling in the bathroom and pushing and pulling in the clinician zone. The physical elements/attributes associated with the offending postures include bathroom configuration, intravenous pole, door, toilet seat height, flush, grab bars, over-bed table, and patient chair. Postural changes, during interactions with the physical environment, constitute the source of most fall events. Physical design must include simultaneous examination of postural changes in day-to-day activities in patient rooms and bathrooms. Among discussed testable recommendations in the article, the followings design strategies should be considered: (a) designing bathrooms to reduce turning as much as possible and (b) designing to avoid motions that involve 2 or more of the offending postures, such as turning and grabbing or grabbing and pulling, and so on.

  15. Significant Lactic Acidosis from Albuterol

    Directory of Open Access Journals (Sweden)

    Deborah Diercks

    2018-03-01

    Full Text Available Lactic acidosis is a clinical entity that demands rapid assessment and treatment to prevent significant morbidity and mortality. With increased lactate use across many clinical scenarios, lactate values themselves cannot be interpreted apart from their appropriate clinical picture. The significance of Type B lactic acidosis is likely understated in the emergency department (ED. Given the mortality that sepsis confers, a serum lactate is an important screening study. That said, it is with extreme caution that we should interpret and react to the resultant elevated value. We report a patient with a significant lactic acidosis. Though he had a high lactate value, he did not require aggressive resuscitation. A different classification scheme for lactic acidosis that focuses on the bifurcation of the “dangerous” and “not dangerous” causes of lactic acidosis may be of benefit. In addition, this case is demonstrative of the potential overuse of lactates in the ED.

  16. Building Sustainable Futures: Emerging Understandings of the Significant Contribution of the Professional Learning Community

    Science.gov (United States)

    Andrews, Dorothy; Lewis, Marian

    2004-01-01

    This article draws on the experiences of a range of Australian schools engaging with a teacher-centred process of whole-school renewal known as IDEAS (Innovative Designs for Enhancing Achievement in Schools). IDEAS enhances the professional capacity of teachers to improve school outcomes such as student learning, relationships with the community,…

  17. Complementary contribution on the practical significance in the results of Young Self-Report

    Directory of Open Access Journals (Sweden)

    César Merino-Soto

    2016-12-01

    Full Text Available Sr. Editor En los hallazgos de Alarcón y Bárrig (2015 recientemente aparecidos, se encuentran resultados que esencialmente parecen replicar lo reportado en estudios anteriores sobre el tema. Esto añade evidencia acumulativa sobre las tendencias conductuales de las diferencias entre varones y mujeres respecto de los problemas de conducta, luego de más de una década en que se presentaron hallazgos similares en la población peruana (Majluf, 1999. No obstante, la presentación de sus resultados oscurece un tipo de información más útil, pues las autoras han priorizado únicamente el marco de la significancia estadística en la interpretación de sus análisis y en la sustentación de sus conclusiones. No se ha añadido algún comentario sobre la magnitud de las diferencias o lo que también se denomina significancia práctica. Actualmente, el reporte de la significancia práctica tiene un lugar obligado, y no solo recomendado, por el Manual de publicaciones de la American Psychological Association (APA, 2010, lo que ha impulsado que sea un componente sine qua non de los manuscritos sometidos a revistas científicas para su eventual publicación, sea para estudios cualitativos (p. ej., Duran et al., 2006 como cuantitativos (Coe y Merino, 2003; Merino, 2011.

  18. Fragrance mix II in the baseline series contributes significantly to detection of fragrance allergy

    DEFF Research Database (Denmark)

    Heisterberg, Maria V; Andersen, Klaus E; Avnstorp, Christian

    2010-01-01

    Fragrance mix II (FM II) is a relatively new screening marker for fragrance contact allergy. It was introduced in the patch test baseline series in Denmark in 2005 and contains six different fragrance chemicals commonly present in cosmetic products and which are known allergens.......Fragrance mix II (FM II) is a relatively new screening marker for fragrance contact allergy. It was introduced in the patch test baseline series in Denmark in 2005 and contains six different fragrance chemicals commonly present in cosmetic products and which are known allergens....

  19. Minute Impurities Contribute Significantly to Olfactory Receptor Ligand Studies: Tales from Testing the Vibration Theory

    OpenAIRE

    Paoli, M.; M?nch, D.; Haase, A.; Skoulakis, E.; Turin, L.; Galizia, C. G.

    2017-01-01

    Several studies have attempted to test the vibrational hypothesis of odorant receptor activation in behavioral and physiological studies using deuterated compounds as odorants. The results have been mixed. Here, we attempted to test how deuterated compounds activate odorant receptors using calcium imaging of the fruit fly antennal lobe. We found specific activation of one area of the antennal lobe corresponding to inputs from a specific receptor. However, upon more detailed analysis, we disco...

  20. Minute Impurities Contribute Significantly to Olfactory Receptor Ligand Studies: Tales from Testing the Vibration Theory.

    Science.gov (United States)

    Paoli, M; Münch, D; Haase, A; Skoulakis, E; Turin, L; Galizia, C G

    2017-01-01

    Several studies have attempted to test the vibrational hypothesis of odorant receptor activation in behavioral and physiological studies using deuterated compounds as odorants. The results have been mixed. Here, we attempted to test how deuterated compounds activate odorant receptors using calcium imaging of the fruit fly antennal lobe. We found specific activation of one area of the antennal lobe corresponding to inputs from a specific receptor. However, upon more detailed analysis, we discovered that an impurity of 0.0006% ethyl acetate in a chemical sample of benzaldehyde-d 5 was entirely responsible for a sizable odorant-evoked response in Drosophila melanogaster olfactory receptor cells expressing dOr42b. Without gas chromatographic purification within the experimental setup, this impurity would have created a difference in the responses of deuterated and nondeuterated benzaldehyde, suggesting that dOr42b be a vibration sensitive receptor, which we show here not to be the case. Our results point to a broad problem in the literature on use of non-GC-pure compounds to test receptor selectivity, and we suggest how the limitations can be overcome in future studies.

  1. Clathrin-independent pathways do not contribute significantly to endocytic flux.

    Science.gov (United States)

    Bitsikas, Vassilis; Corrêa, Ivan R; Nichols, Benjamin J

    2014-09-17

    Several different endocytic pathways have been proposed to function in mammalian cells. Clathrin-coated pits are well defined, but the identity, mechanism and function of alternative pathways have been controversial. Here we apply universal chemical labelling of plasma membrane proteins to define all primary endocytic vesicles, and labelling of specific proteins with a reducible SNAP-tag substrate. These approaches provide high temporal resolution and stringent discrimination between surface-connected and intracellular membranes. We find that at least 95% of the earliest detectable endocytic vesicles arise from clathrin-coated pits. GPI-anchored proteins, candidate cargoes for alternate pathways, are also found to enter the cell predominantly via coated pits. Experiments employing a mutated clathrin adaptor reveal distinct mechanisms for sorting into coated pits, and thereby explain differential effects on the uptake of transferrin and GPI-anchored proteins. These data call for a revision of models for the activity and diversity of endocytic pathways in mammalian cells.

  2. Researchers' Perceptions of Statistical Significance Contribute to Bias in Health and Exercise Science

    Science.gov (United States)

    Buchanan, Taylor L.; Lohse, Keith R.

    2016-01-01

    We surveyed researchers in the health and exercise sciences to explore different areas and magnitudes of bias in researchers' decision making. Participants were presented with scenarios (testing a central hypothesis with p = 0.06 or p = 0.04) in a random order and surveyed about what they would do in each scenario. Participants showed significant…

  3. Phenolic acids significantly contribute to antioxidant potency of Gynostemma pentaphyllum aqueous and methanol extracts

    Czech Academy of Sciences Publication Activity Database

    Samec, D.; Valek-Zulj, L.; Martinez, S.; Grúz, Jiří; Piljac, A.; Piljac-Žegarac, J.

    2016-01-01

    Roč. 84, JUN (2016), s. 104-107 ISSN 0926-6690 R&D Projects: GA ČR GA14-34792S; GA MŠk(CZ) LO1204; GA MŠk LK21306 Institutional support: RVO:61389030 Keywords : Gynostemma pentaphyllum * Phenolic acids * Mass spectrometry Subject RIV: CE - Biochemistry Impact factor: 3.181, year: 2016

  4. The historical significance of oak

    Science.gov (United States)

    J. V. Thirgood

    1971-01-01

    A brief history of the importance of oak in Europe, contrasting the methods used in France and Britain to propagate the species and manage the forests for continued productivity. The significance of oak as a strategic resource during the sailing-ship era is stressed, and mention is made of the early development of oak management in North America. The international...

  5. Interannual variability of the stratospheric wave driving during northern winter

    Directory of Open Access Journals (Sweden)

    H. M. Kelder

    2007-05-01

    Full Text Available The strength of the stratospheric wave driving during northern winter is often quantified by the January–February mean poleward eddy heat flux at 100 hPa, averaged over 40°–80° N (or a similar area and period. Despite the dynamical and chemical relevance of the wave driving, the causes for its variability are still not well understood. In this study, ERA-40 reanalysis data for the period 1979–2002 are used to examine several factors that significantly affect the interannual variability of the wave driving. The total poleward heat flux at 100 hPa is poorly correlated with that in the troposphere, suggesting a decoupling between 100 hPa and the troposphere. However, the individual zonal wave-1 and wave-2 contributions to the wave driving at 100 hPa do exhibit a significant coupling with the troposphere, predominantly their stationary components. The stationary wave-1 contribution to the total wave driving significantly depends on the latitude of the stationary wave-1 source in the troposphere. The results suggest that this dependence is associated with the varying ability of stationary wave-1 activity to enter the tropospheric waveguide at mid-latitudes. The wave driving anomalies are separated into three parts: one part due to anomalies in the zonal correlation coefficient between the eddy temperature and eddy meridional wind, another part due to anomalies in the zonal eddy temperature amplitude, and a third part due to anomalies in the zonal eddy meridional wind amplitude. It is found that year-to-year variability in the zonal correlation coefficient between the eddy temperature and the eddy meridional wind is the most dominant factor in explaining the year-to-year variability of the poleward eddy heat flux.

  6. Respiratory neuroplasticity - Overview, significance and future directions.

    Science.gov (United States)

    Fuller, David D; Mitchell, Gordon S

    2017-01-01

    Neuroplasticity is an important property of the neural system controlling breathing. However, our appreciation for its importance is still relatively new, and we have much to learn concerning different forms of plasticity, their underlying mechanisms, and their biological and clinical significance. In this brief review, we discuss several well-studied models of respiratory plasticity, including plasticity initiated by inactivity in the respiratory system, intermittent and sustained hypoxia, and traumatic injury to the spinal cord. Other aspects of respiratory plasticity are considered in other contributions to this special edition of Experimental Neurology on respiratory plasticity. Finally, we conclude with discussions concerning the biological and clinical significance of respiratory motor plasticity, and areas in need of future research effort. Copyright © 2016. Published by Elsevier Inc.

  7. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1994-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October - December 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  8. Synthetic definition of biological significance

    International Nuclear Information System (INIS)

    Buffington, J.D.

    1975-01-01

    The central theme of the workshop is recounted and the views of the authors are summarized. Areas of broad agreement or disagreement, unifying principles, and research needs are identified. Authors' views are consolidated into concepts that have practical utility for the scientist making impact assessments. The need for decision-makers and managers to be cognizant of the recommendations made herein is discussed. Finally, bringing together the diverse views of the workshop participants, a conceptual definition of biological significance is synthesized

  9. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-11-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July - September 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  10. The effect of organisational context variables on employer attitudes toward employability of ex-offenders.

    Science.gov (United States)

    Lukies, John; Graffam, Joseph; Shinkfield, Alison J

    2011-05-01

    The authors tested the premise that organisational context variables (i.e., size of organisation, industry type, location, and respondent's position in organisation) had significant effects on employer (N = 596) attitudes toward employability of ex-offenders. They also examined whether organisational context variables had an equivalent effect on employer attitudes to that of job-seeker criminal history and employer personal characteristics (e.g., respondent age and gender). Using linear regression (HLM 6.02a), organisational context variables were shown to have a significant effect on employer attitudes. In addition, organisational context variables had a significantly greater effect on employer attitudes than did employer personal characteristics. However, job-seeker criminal history contributed more to respondent ratings of ex-offender employability than did organisational context variables. The finding that judgements of employability are influenced by organisational context variables has implications for future research relevant to reintegration. Stakeholder attitudes toward the reintegration success of ex-offenders may be generally influenced by context variables.

  11. Amplification factor variable amplifier

    NARCIS (Netherlands)

    Akitsugu, Oshita; Nauta, Bram

    2007-01-01

    PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ; SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and

  12. Amplification factor variable amplifier

    NARCIS (Netherlands)

    Akitsugu, Oshita; Nauta, Bram

    2010-01-01

    PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ;SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and can

  13. Fisher's Contributions to Statistics

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 9. Fisher's Contributions to Statistics. T Krishnan. General Article Volume 2 Issue 9 September 1997 pp 32-37. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/002/09/0032-0037. Author Affiliations.

  14. Newton's Contributions to Optics

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 12. Newton's Contributions to Optics. Arvind Kumar. General Article Volume 11 Issue 12 December 2006 pp 10-20. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/011/12/0010-0020. Keywords.

  15. The contribution of epidemiology

    NARCIS (Netherlands)

    Brandt, P. van den; Voorrips, L.; Hertz-Picciotto, I.; Shuker, D.; Boeing, H.; Speijers, G.; Guittard, C.; Kleiner, J.; Knowles, M.; Wolk, A.; Goldbohm, A.

    2002-01-01

    Epidemiologic studies directly contribute data on risk (or benefit) in humans as the investigated species, and in the full food intake range normally encountered by humans. This paper starts with introducing the epidemiologic approach, followed by a discussion of perceived differences between

  16. Variable Selection via Partial Correlation.

    Science.gov (United States)

    Li, Runze; Liu, Jingyuan; Lou, Lejia

    2017-07-01

    Partial correlation based variable selection method was proposed for normal linear regression models by Bühlmann, Kalisch and Maathuis (2010) as a comparable alternative method to regularization methods for variable selection. This paper addresses two important issues related to partial correlation based variable selection method: (a) whether this method is sensitive to normality assumption, and (b) whether this method is valid when the dimension of predictor increases in an exponential rate of the sample size. To address issue (a), we systematically study this method for elliptical linear regression models. Our finding indicates that the original proposal may lead to inferior performance when the marginal kurtosis of predictor is not close to that of normal distribution. Our simulation results further confirm this finding. To ensure the superior performance of partial correlation based variable selection procedure, we propose a thresholded partial correlation (TPC) approach to select significant variables in linear regression models. We establish the selection consistency of the TPC in the presence of ultrahigh dimensional predictors. Since the TPC procedure includes the original proposal as a special case, our theoretical results address the issue (b) directly. As a by-product, the sure screening property of the first step of TPC was obtained. The numerical examples also illustrate that the TPC is competitively comparable to the commonly-used regularization methods for variable selection.

  17. Fritz Schott's Contributions to the Understanding of the Ocean Circulation

    Science.gov (United States)

    Visbeck, M.

    2009-04-01

    The ocean circulation and its central significance for global climate lay at the heart of Fritz's research. In the context of hard-won data from his more than 30 research cruises to key regions of the Atlantic and Indian oceans, he made fundamental contributions to our understanding of the wind-driven and thermohaline ocean circulation. His insights and explorations of circulation and dynamics of the tropical Indian and Atlantic Oceans have led the field and provided a large part of the basis for planning large, international experiments. Fritz's work is also distinguished by his making exceptional use of modeling results, increasingly as the models have improved. His research has provided a much clearer correspondence between the observed ocean-structure and dynamical theory-noting both theoretical successes and limitations. Besides his general interest in the physical oceanography of the World Oceans, most of his research was devoted to the dynamics of tropical oceans with its intense and highly variable current systems. Concerning the Indian Ocean, Fritz's investigated the response of the Somali Current system to the variable monsoon winds in the early 1980's, obtaining high-quality, hydrographic surveys and the first long term direct measurement of ocean currents from moored arrays. His analyses and interpretations provided a synthesis of the complex circulations there. In the tropical Atlantic Ocean Fritz research focused on the western boundary circulation with important contributions to the understanding of the North Brazil Current retroflection, and the variability of the shallow and deep western boundary currents. Trying to solve the fundamental question ‘what is the role of the tropical ocean for climate variability', Fritz initiated large multinational research programs under the umbrella of the World Climate Research Projects WOCE (World Ocean Circulation Experiment) and CLIVAR (Climate Variability and Predictability). Fritz was the initiator and

  18. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-09-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  19. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1990) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. Also included are a number of enforcement actions that had been previously resolved but not published in this NUREG. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  20. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  1. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-02-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1990) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  2. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  3. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-11-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1990) and includes copies of letters, notices, and orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  4. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-08-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  5. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1990-09-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April--June 1990) and includes copies of letters, notices, and orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  6. Clinical significance of neonatal menstruation.

    Science.gov (United States)

    Brosens, Ivo; Benagiano, Giuseppe

    2016-01-01

    Past studies have clearly shown the existence of a spectrum of endometrial progesterone responses in neonatal endometrium, varying from proliferation to full decidualization with menstrual-like shedding. The bleedings represent, similar to what occurs in adult menstruation, a progesterone withdrawal bleeding. Today, the bleeding is completely neglected and considered an uneventful episode of no clinical significance. Yet clinical studies have linked the risk of bleeding to a series of events indicating fetal distress. The potential link between the progesterone response and major adolescent disorders requires to be investigated by prospective studies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-06-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  8. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-05-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  9. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-12-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1993) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  10. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1993-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1992) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  11. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-07-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (April-June 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  12. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1991-11-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  13. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1992-03-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (October--December 1991) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  14. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1989-06-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (January--March 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. Also included are a number of enforcement actions that had been previously resolved but not published in this NUREG. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  15. Enforcement actions: Significant actions resolved

    International Nuclear Information System (INIS)

    1989-12-01

    This compilation summarizes significant enforcement actions that have been resolved during one quarterly period (July--September 1989) and includes copies of letters, Notices, and Orders sent by the Nuclear Regulatory Commission to licensees with respect to these enforcement actions. It is anticipated that the information in this publication will be widely disseminated to managers and employees engaged in activities licensed by the NRC, so that actions can be taken to improve safety by avoiding future violations similar to those described in this publication

  16. Ownership and care in culturally significant architecture: Three case ...

    African Journals Online (AJOL)

    fire resistance, as well as thermal and acoustic insulation properties that contribute to the interior comfort of dwellings. The shortcomings are mainly low ..... The building is at most only significant to students in architecture and South African ...

  17. EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

    Science.gov (United States)

    The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

  18. Impact of weather variability on nitrate leaching

    Science.gov (United States)

    Richards, Karl; Premrov, Alina; Hackett, Richard; Coxon, Catherine

    2016-04-01

    The loss of nitrate (NO3 - N) to water via leaching and overland flow contributes to eutrophication of freshwaters, transitional and near coastal waters with agriculture contributing significantly to nitrogen (N) loading to these water. Environmental regulations, such as the Nitrates and Water Framework Directives, have increased constraints on farmers to improve N management in regions at risk of NO3--N loss to water. In addition, farmers also have to manage their systems within a changing climate as the imapcts of climate change begin to impact resulting in more frequent extreme events such as floods and droughts. The objective of this study was to investigate the link between weather volatility and the concentration of leached NO3--N spring barley. Leaching was quantified under spring barley grown on a well-drained, gravelly sandy soil using ceramic cup samplers over 6 drainage years under the same farming practices and treatments. Soil solution NO3--N concentrations under spring barley grown by conventional inversion ploughing and reduced tillage were compared to weather parameters over the period. Weather was recorded at a national Met Eireann weather station on site. Soil solution NO3--N varied significantly between years. Within individual years NO3--N concentrations varied over the drainage season, with peak concentrations generally observed in the autumn time, decreasing thereafter. Under both treatments there was a three-fold difference in mean annual soil solution NO3--N concentration over the 6 years with no change in the agronomic practices (crop type, tillage type and fertiliser input). Soil solution nitrate concentrations were significantly influenced by weather parameters such as rainfall, effective drainage and soil moisture deficit. The impact of climate change in Ireland could lead to increased NO3--N loss to water further exacerbating eutrophication of sensitive estuaries. The increased impact on eutrophication of waters, related to climatic

  19. Vertical jump fatigue does not affect intersegmental coordination and segmental contribution

    Directory of Open Access Journals (Sweden)

    Gleber Pereira

    2014-09-01

    Full Text Available The aim of this study was to describe the intersegmental coordination and segmental contribution during intermittent vertical jumps performed until fatigue. Seven male visited the laboratory on two occasions: 1 the maximum vertical jump height was determined followed by vertical jumps habituation; 2 participants performed intermittent countermovement jumps until fatigue. Kinematic and kinetic variables were recorded. The overall reduction in vertical jump height was 5,5%, while the movement duration increased 10% during the test. The thigh segment angle at movement reversal significantly increased as the exercise progressed. Non-significant effect of fatigue on movement synergy was found for the intersegmental coordination pattern. More than 90% of the intersegmental coordination was explained by one coordination pattern. Thigh rotation contributed the most to the intersegmental coordination pattern, with the trunk second and the shank the least. Therefore, one intersegmental coordination pattern is followed throughout the vertical jumps until fatigue and thigh rotation contributes the most to jump height.

  20. Moral significance of phenomenal consciousness.

    Science.gov (United States)

    Levy, Neil; Savulescu, Julian

    2009-01-01

    Recent work in neuroimaging suggests that some patients diagnosed as being in the persistent vegetative state are actually conscious. In this paper, we critically examine this new evidence. We argue that though it remains open to alternative interpretations, it strongly suggests the presence of consciousness in some patients. However, we argue that its ethical significance is less than many people seem to think. There are several different kinds of consciousness, and though all kinds of consciousness have some ethical significance, different kinds underwrite different kinds of moral value. Demonstrating that patients have phenomenal consciousness--conscious states with some kind of qualitative feel to them--shows that they are moral patients, whose welfare must be taken into consideration. But only if they are subjects of a sophisticated kind of access consciousness--where access consciousness entails global availability of information to cognitive systems--are they persons, in the technical sense of the word employed by philosophers. In this sense, being a person is having the full moral status of ordinary human beings. We call for further research which might settle whether patients who manifest signs of consciousness possess the sophisticated kind of access consciousness required for personhood.

  1. Factors Contributing Decreased Performance Of Slow Learners

    Directory of Open Access Journals (Sweden)

    Dr. L. Kannan

    2015-03-01

    compared to less than 50 percentage of marks majority 3666 have less than 80 percentage of attendance this difference of observation among both genders has got statistical significance p0.007were male students with low performance has got low percentage of attendance. In this study the family type has gotno association with the level of performance. To analyze simultaneously on all the variables gender understanding the language unable to study on their own unhappy with the subjects and problem with their class mates. These answers differ significantly among low performers compared to high performers. Finally the study has been concluded that low achievers slow learners needs to concentrate on their regularity of attending their classes so that to have a better performance in their subsequent internal examinations. Many students felt they were not able to study on their own and perform in their internal assessment examination so students can be encouraged group discussions and effective mentorship programme can be generated in order to have better performance in their internal examinations.

  2. Continuous-variable quantum games

    International Nuclear Information System (INIS)

    Li Hui; Du Jiangfeng; Massar, Serge

    2002-01-01

    We investigate the quantization of games in which the players can access to a continuous set of classical strategies, making use of continuous-variable quantum systems. For the particular case of the Cournot's duopoly, we find that, even though the two players both act as 'selfishly' in the quantum game as they do in the classical game, they are found to virtually cooperate due to the quantum entanglement between them. We also find that the original Einstein-Podolksy-Rosen state contributes to the best profits that the two firms could ever attain. Moreover, we propose a practical experimental setup for the implementation of such quantum games

  3. Bet-hedging response to environmental variability, an intraspecific comparison.

    Science.gov (United States)

    Nevoux, Marie; Forcada, Jaume; Barbraud, Christophe; Croxall, John; Weimerskirchi, Henri

    2010-08-01

    A major challenge in ecology is to understand the impact of increased environmental variability on populations and ecosystems. To maximize their fitness in a variable environment, life history theory states that individuals should favor a bet-hedging strategy, involving a reduction of annual breeding performance and an increase in adult survival so that reproduction can be attempted over more years. As a result, evolution toward longer life span is expected to reduce the deleterious effects of extra variability on population growth, and consequently on the trait contributing the most to it (e.g., adult survival in long-lived species). To investigate this, we compared the life histories of two Black-browed Albatross (Thalassarche melanophrys) populations breeding at South Georgia (Atlantic Ocean) and Kerguelen (Indian Ocean), the former in an environment nearly three times more variable climatically (e.g., in sea surface temperature) than the latter. As predicted, individuals from South Georgia (in the more variable environment) showed significantly higher annual adult survival (0.959, SE = 0.003) but lower annual reproductive success (0.285 chick per pair, SE = 0.039) than birds from Kerguelen (survival = 0.925, SE = 0.004; breeding success = 0.694, SE = 0.027). In both populations, climatic conditions affected the breeding success and the survival of inexperienced breeders, whereas the survival of experienced breeders was unaffected. The strength of the climatic impact on survival of inexperienced breeders was very similar between the two populations, but the effect on breeding success was positively related to environmental variability. These results provide rare and compelling evidence to support bet-hedging underlying changes in life history traits as an adaptive response to environmental variability.

  4. [Placebo effect: a contribution of social psychology].

    Science.gov (United States)

    Balez, R; Leroyer, C; Couturaud, F

    2014-10-01

    This article reviews the psychosocial variables, which are of interest in the relationship between the patient and the physician. According to a classical model of social psychology, such a relationship might contribute to the placebo/nocebo effects. We develop herein various relational and contextual variables, taking into account four dimensions (intra-individual, interpersonal, positional and ideological) and their potential effects on therapeutic responses. This applies both in the setting of daily clinical practice and of clinical trials. The placebo effect offers an opportunity for collaboration and dialogue between social scientists and physicians.

  5. The significance of IL-1β +3953C>T, IL-6 -174G>C and -596G>A, TNF-α -308G>A gene polymorphisms and 86 bp variable number tandem repeat polymorphism of IL-1RN in bronchopulmonary dysplasia in infants born before 32 weeks of gestation

    Directory of Open Access Journals (Sweden)

    Dawid Szpecht

    2017-06-01

    Full Text Available Introduction : Bronchopulmonary dysplasia (BPD is a chronic lung disease that affects primarily preterm infants. Genetic factors are also taken into consideration in the pathogenesis of BPD. Genetic predispositions to higher production of inflammation mediators seem to be crucial. Material and methods: The aim of this study was to evaluate the possible relationship between polymorphisms: interleukin-1β +3953 C>T, interleukin-6 -174 G>C and -596 G>A, tumour necrosis factor -308 G>A and interleukin-1RN VNTR 86bp and the occurrence of BPD in a population of 100 preterm infants born from singleton pregnancy, before 32+0 weeks of gestation, exposed to antenatal steroids therapy, and without congenital abnormalities.  Results : In the study population BPD was diagnosed in 36 (36% newborns. Among the studied polymorphisms we found the higher prevalence for BPD developing of the following genotypes: 1/2 (OR 1.842 [0.673-5.025] and 2/2 IL-1RN (OR 1.75 [0.418-6.908] 86bpVNTR; GC (2.222 [0.658-8.706] and CC IL-6 -174G>C (1.6 [0.315-8.314] and GA (2.753 [0.828-10.64] and AA (1.5 [0.275-8.067] IL-6 -596G>A, GA 1.509 (0.515-4.301 TNF-α -308G>A. However, these finding were not statistically significant.  Conclusions : Genetic factors are undeniably involved in the pathogenesis of BPD. In the times of individualised therapy finding genes responsible for BPD might allow the development of new treatment strategies. A new way of specific therapy could ensure the reduction of complications connected with BPD and treatment costs.

  6. THE CONTRIBUTION OF TEACHERS’ PERSONAL RELATIONSHIP AND THEIR PERCEPTION OF SUPERVISION IMPLEMENTATION TOWARD WORK ACHIEVEMENT MOTIVATION

    Directory of Open Access Journals (Sweden)

    Fitriadi Lubis

    2018-04-01

    Full Text Available The purpose of this research is to examine the relationship between teachers’ interpersonal relationship and their perception about supervision implementation and their contribution toward their work achievement motivation. The data were obtained from 55 teachers as the sample by stratified proportional random sampling. The data were analyzed by means of correlation and multiple regression technique. The results of this study show that the contribution of interpersonal relationship variable was 28% to work achievement. Meanwhile, the teachers’ perception of supervision implementation variable contributes 17% to work achievement motivation variable. The contribution of the two dependent variables was 41% to work achievement motivation variable.

  7. Variable mechanical ventilation.

    Science.gov (United States)

    Fontela, Paula Caitano; Prestes, Renata Bernardy; Forgiarini, Luiz Alberto; Friedman, Gilberto

    2017-01-01

    To review the literature on the use of variable mechanical ventilation and the main outcomes of this technique. Search, selection, and analysis of all original articles on variable ventilation, without restriction on the period of publication and language, available in the electronic databases LILACS, MEDLINE®, and PubMed, by searching the terms "variable ventilation" OR "noisy ventilation" OR "biologically variable ventilation". A total of 36 studies were selected. Of these, 24 were original studies, including 21 experimental studies and three clinical studies. Several experimental studies reported the beneficial effects of distinct variable ventilation strategies on lung function using different models of lung injury and healthy lungs. Variable ventilation seems to be a viable strategy for improving gas exchange and respiratory mechanics and preventing lung injury associated with mechanical ventilation. However, further clinical studies are necessary to assess the potential of variable ventilation strategies for the clinical improvement of patients undergoing mechanical ventilation.

  8. The significance of small streams

    Science.gov (United States)

    Wohl, Ellen

    2017-09-01

    Headwaters, defined here as first- and secondorder streams, make up 70%‒80% of the total channel length of river networks. These small streams exert a critical influence on downstream portions of the river network by: retaining or transmitting sediment and nutrients; providing habitat and refuge for diverse aquatic and riparian organisms; creating migration corridors; and governing connectivity at the watershed-scale. The upstream-most extent of the channel network and the longitudinal continuity and lateral extent of headwaters can be difficult to delineate, however, and people are less likely to recognize the importance of headwaters relative to other portions of a river network. Consequently, headwaters commonly lack the legal protections accorded to other portions of a river network and are more likely to be significantly altered or completely obliterated by land use.

  9. No significant fuel failures (NSFF)

    International Nuclear Information System (INIS)

    Domaratzki, Z.

    1979-01-01

    It has long been recognized that no emergency core cooling system (ECCS) could be absolutely guaranteed to prevent fuel failures. In 1976 the Atomic Energy Control Board decided that the objective for an ECCS should be to prevent fuel failures, but if the objective could not be met it should be shown that the consequences are acceptable for dual failures comprising any LOCA combined with an assumed impairment of containment. Out of the review of the Bruce A plant came the definition of 'no significant fuel failures': for any postulated LOCA combined with any one mode of containment impairment the resultant dose to a person at the edge of the exclusion zone is less than the reference dose limits for dual failures

  10. Ritual Significance in Mycenaean Hairstyles

    Directory of Open Access Journals (Sweden)

    Hsu, Florence Sheng-chieh

    2012-04-01

    Full Text Available Although the frescoes excavated from Bronze Age sites on the Greek mainland provide evidence for female figures in the Mycenaean society, the hairstyles of these figures have not been studied in detail. As in many other ancient cultures, hairstyles were not only an exhibition of beauty and fashion, but they also represented certain age groups or a person’s social status. The Mycenaeans inherited many of their hairstyles from their Minoan predecessors, although differences existed as well. It is also possible there may have been a shift in meaning for seemingly similar looking hairstyles from the Minoan to the Mycenaean periods. Female figures, which compose most of the Mycenaean figures in frescoes known to date, are fine examples for discussing the artistic representation and potential significance of Mycenaean hairstyles. By comparing with Minoan hairstyles, discussions of Mycenaean examples lead to conclusions in the relationship between hairstyles and ritual activities in the Mycenaean society.

  11. Recent changes in county-level corn yield variability in the United States from observations and crop models

    Energy Technology Data Exchange (ETDEWEB)

    Leng, Guoyong

    2017-12-01

    The United States is responsible for 35% and 60% of global corn supply and exports. Enhanced supply stability through a reduction in the year-to-year variability of US corn yield would greatly benefit global food security. Important in this regard is to understand how corn yield variability has evolved geographically in the history and how it relates to climatic and non-climatic factors. Results showed that year-to-year variation of US corn yield has decreased significantly during 1980-2010, mainly in Midwest Corn Belt, Nebraska and western arid regions. Despite the country-scale decreasing variability, corn yield variability exhibited an increasing trend in South Dakota, Texas and Southeast growing regions, indicating the importance of considering spatial scales in estimating yield variability. The observed pattern is partly reproduced by process-based crop models, simulating larger areas experiencing increasing variability and underestimating the magnitude of decreasing variability. And 3 out of 11 models even produced a differing sign of change from observations. Hence, statistical model which produces closer agreement with observations is used to explore the contribution of climatic and non-climatic factors to the changes in yield variability. It is found that climate variability dominate the change trends of corn yield variability in the Midwest Corn Belt, while the ability of climate variability in controlling yield variability is low in southeastern and western arid regions. Irrigation has largely reduced the corn yield variability in regions (e.g. Nebraska) where separate estimates of irrigated and rain-fed corn yield exist, demonstrating the importance of non-climatic factors in governing the changes in corn yield variability. The results highlight the distinct spatial patterns of corn yield variability change as well as its influencing factors at the county scale. I also caution the use of process-based crop models, which have substantially underestimated

  12. Bribery or just desserts? Evidence on the influence of Congressional reproductive policy voting patterns on PAC contributions from exogenous variation in the sex mix of legislator offspring.

    Science.gov (United States)

    Conley, Dalton; McCabe, Brian J

    2012-01-01

    Evidence on the relationship between political contributions and legislators' voting behavior is marred by concerns about endogeneity in the estimation process. Using a legislator's offspring sex mix as a truly exogenous variable, we employ an instrumental variable estimation procedure to predict the effect of voting behavior on political contributions. Following previous research, we find that a legislator's proportion daughters has a significant effect on voting behavior for women's issues, as measured by score in the "Congressional Record on Choice" issued by NARAL Pro-Choice America. In the second stage, we make a unique contribution by demonstrating a significant impact of exogenous voting behavior on PAC contributions, lending further credibility to the hypothesis that Political Action Committees respond to legislators' voting patterns by "rewarding" political candidates that vote in line with the positions of the PAC, rather than affecting those same votes - at least in this high-profile policy domain. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. PREDICTIVE CONTRIBUTION OF MORPHOLOGICAL CHARACTERISTICS AND MOTOR ABILITIES ON THE RESULT OF RUNNING THE 60m HURDLES IN BOYS AGED 12 - 13 YEARS

    Directory of Open Access Journals (Sweden)

    Zana Bujak

    2014-06-01

    Full Text Available The subject of this study is to determine predictive contributions of morphological characteristics and motor abilities on the 60m hurdles, with an aim to form a group of easily applicable field tests so as to identify boys who are talented in hurdl e racing . The subject sample of this study was comprised of 60 boys aged 12 - 13. The variable sample consisted of a 60m hurdles criterion variable and a set of 13 p re dictor variables comprising of morphological characteristics, speed - strength abilities and the subjects' coordina tion qualities . Applying the regression analysis , the predictive contribution of a complete variable s et of morpholog ical characteristics and motor abilities was determined as an above average statistical significance, influencing 60m hurdle outcome. The greatest individual statistically significant predictive contribution was achieved by the variables of speed - strength quality assessment: 20m flying start r ace result with a standing long jump; and only one variable from the field of morphological characteristics: the shin length. The results support the following conclusion: the two specific variables of speed - strength quality, and 20m flying start race results along with standing long jump , can be relevant predictors of successful outcome in hurdle races .

  14. The contribution of personality traits and academic and social adjustment to life satisfaction and depression in college freshmen

    Directory of Open Access Journals (Sweden)

    Sanja Smojver-Ažić

    2010-11-01

    Full Text Available The aim of this study is to investigate the role of personality traits and student academic and social college adjustment to their overall life satisfaction and depression. Sample of 492 freshmen completed a battery of measures. Hierarchical regression analyses are applied to analyze the contribution of predictor variables on life satisfaction and depression in the group of male and female students. After controlling for the personality traits, college adjustment had a significant contribution to student depression and life satisfaction. Optimism has a significant protective role only with male, but not with female students.

  15. Abstracts of contributed papers

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.

  16. Contributions to statistics

    CERN Document Server

    Mahalanobis, P C

    1965-01-01

    Contributions to Statistics focuses on the processes, methodologies, and approaches involved in statistics. The book is presented to Professor P. C. Mahalanobis on the occasion of his 70th birthday. The selection first offers information on the recovery of ancillary information and combinatorial properties of partially balanced designs and association schemes. Discussions focus on combinatorial applications of the algebra of association matrices, sample size analogy, association matrices and the algebra of association schemes, and conceptual statistical experiments. The book then examines latt

  17. Contributions to sampling statistics

    CERN Document Server

    Conti, Pier; Ranalli, Maria

    2014-01-01

    This book contains a selection of the papers presented at the ITACOSM 2013 Conference, held in Milan in June 2013. ITACOSM is the bi-annual meeting of the Survey Sampling Group S2G of the Italian Statistical Society, intended as an international  forum of scientific discussion on the developments of theory and application of survey sampling methodologies and applications in human and natural sciences. The book gathers research papers carefully selected from both invited and contributed sessions of the conference. The whole book appears to be a relevant contribution to various key aspects of sampling methodology and techniques; it deals with some hot topics in sampling theory, such as calibration, quantile-regression and multiple frame surveys, and with innovative methodologies in important topics of both sampling theory and applications. Contributions cut across current sampling methodologies such as interval estimation for complex samples, randomized responses, bootstrap, weighting, modeling, imputati...

  18. Genes contributing to prion pathogenesis

    DEFF Research Database (Denmark)

    Tamgüney, Gültekin; Giles, Kurt; Glidden, David V

    2008-01-01

    incubation times, indicating that the conversion reaction may be influenced by other gene products. To identify genes that contribute to prion pathogenesis, we analysed incubation times of prions in mice in which the gene product was inactivated, knocked out or overexpressed. We tested 20 candidate genes...... show that many genes previously implicated in prion replication have no discernible effect on the pathogenesis of prion disease. While most genes tested did not significantly affect survival times, ablation of the amyloid beta (A4) precursor protein (App) or interleukin-1 receptor, type I (Il1r1...

  19. Significant biases affecting abundance determinations

    Science.gov (United States)

    Wesson, Roger

    2015-08-01

    I have developed two highly efficient codes to automate analyses of emission line nebulae. The tools place particular emphasis on the propagation of uncertainties. The first tool, ALFA, uses a genetic algorithm to rapidly optimise the parameters of gaussian fits to line profiles. It can fit emission line spectra of arbitrary resolution, wavelength range and depth, with no user input at all. It is well suited to highly multiplexed spectroscopy such as that now being carried out with instruments such as MUSE at the VLT. The second tool, NEAT, carries out a full analysis of emission line fluxes, robustly propagating uncertainties using a Monte Carlo technique.Using these tools, I have found that considerable biases can be introduced into abundance determinations if the uncertainty distribution of emission lines is not well characterised. For weak lines, normally distributed uncertainties are generally assumed, though it is incorrect to do so, and significant biases can result. I discuss observational evidence of these biases. The two new codes contain routines to correctly characterise the probability distributions, giving more reliable results in analyses of emission line nebulae.

  20. Astrobiological significance of chemolithoautotrophic acidophiles

    Science.gov (United States)

    Pikuta, Elena V.; Hoover, Richard B.

    2004-02-01

    For more than a century (since Winogradsky discovered lithautotrophic bacteria) there has been a dilemma in microbiology about life that first inhabited the Earth. Which types of life forms first appeared in the primordial oceans during the earliest geological period on Earth as the primary ancestors of modern biological diversity? How did a metabolism of ancestors evolve: from lithoautotrophic to lithoheterotrophic and organoheterotrophic or from organoheterotrophic to organautotrophic and lithomixotrophic types? At the present time, it is known that chemolithoheterotrophic and chemolithoautotrophic metabolizing bacteria are wide spread in different ecosystems. On Earth the acidic ecosystems are associated with geysers, volcanic fumaroles, hot springs, deep sea hydrothermal vents, caves, acid mine drainage and other technogenic ecosystems. Bioleaching played a significant roel on a global geological scale during the Earth's formation. This important feature of bacteria has been successfully applied in industry. The lithoautotrophs include Bacteria and Archaea belonging to diverse genera containing thermophilic and mesophilic species. In this paper we discuss the lithotrophic microbial acidophiles and present some data with a description of new acidophilic iron- and sulfur-oxidizing bacterium isolated from the Chena Hot Springs in Alaska. We also consider the possible relevance of microbial acidophiles to Venus, Io, and acidic inclusions in glaciers and icy moons.

  1. Statistical Significance for Hierarchical Clustering

    Science.gov (United States)

    Kimes, Patrick K.; Liu, Yufeng; Hayes, D. Neil; Marron, J. S.

    2017-01-01

    Summary Cluster analysis has proved to be an invaluable tool for the exploratory and unsupervised analysis of high dimensional datasets. Among methods for clustering, hierarchical approaches have enjoyed substantial popularity in genomics and other fields for their ability to simultaneously uncover multiple layers of clustering structure. A critical and challenging question in cluster analysis is whether the identified clusters represent important underlying structure or are artifacts of natural sampling variation. Few approaches have been proposed for addressing this problem in the context of hierarchical clustering, for which the problem is further complicated by the natural tree structure of the partition, and the multiplicity of tests required to parse the layers of nested clusters. In this paper, we propose a Monte Carlo based approach for testing statistical significance in hierarchical clustering which addresses these issues. The approach is implemented as a sequential testing procedure guaranteeing control of the family-wise error rate. Theoretical justification is provided for our approach, and its power to detect true clustering structure is illustrated through several simulation studies and applications to two cancer gene expression datasets. PMID:28099990

  2. Genetic contribution to patent ductus arteriosus in the premature newborn.

    Science.gov (United States)

    Bhandari, Vineet; Zhou, Gongfu; Bizzarro, Matthew J; Buhimschi, Catalin; Hussain, Naveed; Gruen, Jeffrey R; Zhang, Heping

    2009-02-01

    The most common congenital heart disease in the newborn population, patent ductus arteriosus, accounts for significant morbidity in preterm newborns. In addition to prematurity and environmental factors, we hypothesized that genetic factors play a significant role in this condition. The objective of this study was to quantify the contribution of genetic factors to the variance in liability for patent ductus arteriosus in premature newborns. A retrospective study (1991-2006) from 2 centers was performed by using zygosity data from premature twins born at Patent ductus arteriosus was diagnosed by echocardiography at each center. Mixed-effects logistic regression was used to assess the effect of specific covariates. Latent variable probit modeling was then performed to estimate the heritability of patent ductus arteriosus, and mixed-effects probit modeling was used to quantify the genetic component. We obtained data from 333 dizygotic twin pairs and 99 monozygotic twin pairs from 2 centers (Yale University and University of Connecticut). Data on chorioamnionitis, antenatal steroids, gestational age, body weight, gender, respiratory distress syndrome, patent ductus arteriosus, necrotizing enterocolitis, oxygen supplementation, and bronchopulmonary dysplasia were comparable between monozygotic and dizygotic twins. We found that gestational age, respiratory distress syndrome, and institution were significant covariates for patent ductus arteriosus. After controlling for specific covariates, genetic factors or the shared environment accounted for 76.1% of the variance in liability for patent ductus arteriosus. Preterm patent ductus arteriosus is highly familial (contributed to by genetic and environmental factors), with the effect being mainly environmental, after controlling for known confounders.

  3. Detection of significant protein coevolution.

    Science.gov (United States)

    Ochoa, David; Juan, David; Valencia, Alfonso; Pazos, Florencio

    2015-07-01

    The evolution of proteins cannot be fully understood without taking into account the coevolutionary linkages entangling them. From a practical point of view, coevolution between protein families has been used as a way of detecting protein interactions and functional relationships from genomic information. The most common approach to inferring protein coevolution involves the quantification of phylogenetic tree similarity using a family of methodologies termed mirrortree. In spite of their success, a fundamental problem of these approaches is the lack of an adequate statistical framework to assess the significance of a given coevolutionary score (tree similarity). As a consequence, a number of ad hoc filters and arbitrary thresholds are required in an attempt to obtain a final set of confident coevolutionary signals. In this work, we developed a method for associating confidence estimators (P values) to the tree-similarity scores, using a null model specifically designed for the tree comparison problem. We show how this approach largely improves the quality and coverage (number of pairs that can be evaluated) of the detected coevolution in all the stages of the mirrortree workflow, independently of the starting genomic information. This not only leads to a better understanding of protein coevolution and its biological implications, but also to obtain a highly reliable and comprehensive network of predicted interactions, as well as information on the substructure of macromolecular complexes using only genomic information. The software and datasets used in this work are freely available at: http://csbg.cnb.csic.es/pMT/. pazos@cnb.csic.es Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. The physiological and biomechanical contributions of poling to roller ski skating.

    Science.gov (United States)

    Sandbakk, Øyvind; Ettema, Gertjan; Holmberg, Hans-Christer

    2013-08-01

    Poling is considered to make a significant contribution to cross-country skiing with the skating technique. To better understand this contribution, the current investigation compared roller ski skating on a treadmill with the so-called G3 skating technique with (G3-P) and without poling (G3-NP). Seven male elite skiers performed 5-min submaximal tests at 8, 12, and 15 km h(-1), as well as an incremental test to exhaustion with both techniques on a 5 % incline. Ventilatory variables were assessed by open-circuit indirect calorimetry and three-dimensional kinematics analyzed using the Qualisys Pro Reflex system. G3-P was associated with approximately 15 % higher peak velocity and 10 % higher peak oxygen uptake than G3-NP in the incremental test (both P skating, specifically by enhancing peak oxygen uptake, skiing efficiency and associated biomechanical variables.

  5. Child protection workers dealing with child abuse: The contribution of personal, social and organizational resources to secondary traumatization.

    Science.gov (United States)

    Dagan, Shlomit Weiss; Ben-Porat, Anat; Itzhaky, Haya

    2016-01-01

    The present study compared secondary traumatization among child protection social workers versus social workers employed at social service departments. In addition, based on Conservation of Resources (COR) theory, the study examined the contribution of working in the field of child protection as well as the contribution of background variables, personal resources (mastery), and resources in the workers' social and organizational environment (social support, effectiveness of supervision, and role stress) to secondary traumatization. The findings indicate that levels of mastery and years of work experience contributed negatively to secondary traumatization, whereas exposure to child maltreatment, trauma history, and role stress contributed positively to secondary traumatization. However, no significant contribution was found for social support and effectiveness of supervision. The study identifies factors that can prevent distress among professionals such as child protection workers, who are exposed to the trauma of child abuse victims. Recommendations are provided accordingly. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Increased heart rate variability during nondirective meditation.

    Science.gov (United States)

    Nesvold, Anders; Fagerland, Morten W; Davanger, Svend; Ellingsen, Øyvind; Solberg, Erik E; Holen, Are; Sevre, Knut; Atar, Dan

    2012-08-01

    Meditation practices are in use for relaxation and stress reduction. Some studies indicate beneficial cardiovascular health effects of meditation. The effects on the autonomous nervous system seem to vary among techniques. The purpose of the present study was to identify autonomic nerve activity changes during nondirective meditation. Heart rate variability (HRV), blood pressure variability (BPV), and baroreflex sensitivity (BRS) were monitored in 27 middle-aged healthy participants of both genders, first during 20 min regular rest with eyes closed, thereafter practising Acem meditation for 20 min. Haemodynamic and autonomic data were collected continuously (beat-to-beat) and non-invasively. HRV and BPV parameters were estimated by power spectral analyses, computed by an autoregressive model. Spontaneous activity of baroreceptors were determined by the sequence method. Primary outcomes were changes in HRV, BPV, and BRS between rest and meditation. HRV increased in the low-frequency (LF) and high-frequency (HF) bands during meditation, compared with rest (p = 0.014, 0.013, respectively). Power spectral density of the RR-intervals increased as well (p = 0.012). LF/HF ratio decreased non-significantly, and a reduction of LF-BPV power was observed during meditation (p < 0.001). There was no significant difference in BRS. Respiration and heart rates remained unchanged. Blood pressure increased slightly during meditation. There is an increased parasympathetic and reduced sympathetic nerve activity and increased overall HRV, while practising the technique. Hence, nondirective meditation by the middle aged may contribute towards a reduction of cardiovascular risk.

  7. Cataclysmic Variable Stars

    Science.gov (United States)

    Hellier, Coel

    2001-01-01

    Cataclysmic variable stars are the most variable stars in the night sky, fluctuating in brightness continually on timescales from seconds to hours to weeks to years. The changes can be recorded using amateur telescopes, yet are also the subject of intensive study by professional astronomers. That study has led to an understanding of cataclysmic variables as binary stars, orbiting so closely that material transfers from one star to the other. The resulting process of accretion is one of the most important in astrophysics. This book presents the first account of cataclysmic variables at an introductory level. Assuming no previous knowledge of the field, it explains the basic principles underlying the variability, while providing an extensive compilation of cataclysmic variable light curves. Aimed at amateur astronomers, undergraduates, and researchers, the main text is accessible to those with no mathematical background, while supplementary boxes present technical details and equations.

  8. Understanding Brown Dwarf Variability

    Science.gov (United States)

    Marley, Mark S.

    2013-01-01

    Surveys of brown dwarf variability continue to find that roughly half of all brown dwarfs are variable. While variability is observed amongst all types of brown dwarfs, amplitudes are typically greatest for L-T transition objects. In my talk I will discuss the possible physical mechanisms that are responsible for the observed variability. I will particularly focus on comparing and contrasting the effects of changes in atmospheric thermal profile and cloud opacity. The two different mechanisms will produce different variability signatures and I will discuss the extent to which the current datasets constrain both mechanisms. By combining constraints from studies of variability with existing spectral and photometric datasets we can begin to construct and test self-consistent models of brown dwarf atmospheres. These models not only aid in the interpretation of existing objects but also inform studies of directly imaged giant planets.

  9. Regional and global significance of nuclear energy

    International Nuclear Information System (INIS)

    Schilling, H.D.

    1995-01-01

    Measures to combat poverty and improve the standard of living in countries of the Third World will inevitably boost global demand for energy, and energy conservation measures will not be able to offset this increase. Nuclear energy will regain significance in the framework of approaches adopted to resolve the energy problem, which primarily is an ecologic problem created by an extremely large flow of materials. The extraordinarily high energy density of nuclear fuels can contribute to markedly reduce the flow of materials; and at that, electric energy is an efficient substitute for primary energy forms. Thus nuclear electricity generation is of double benefit to the ecology. Engineering goals in nuclear technology thus gain a service aspect, with progress in power plant engineering and design aiming not only at enhanced engineered safety, but also at regaining public acceptance of and confidence in nuclear power plant technology. (orig./UA) [de

  10. Significance and potential benefits of the CTBT

    International Nuclear Information System (INIS)

    Sato, M.

    1999-01-01

    This presentation is based on the Treaty stipulation on international cooperation: 'The States parties undertake to promote cooperation among themselves to facilitate and participate in the fullest possible exchange relating to technologies used in the verification of the Non-proliferation Treaty in order to enable States to strengthen national implementation of verification measures; and to enable States to benefit from the application of such technologies for peaceful purposes'. Political significance of the Treaty and the potential benefits of participating in the CTBT regime are exposed. It is concluded that international cooperation under the CTBT regime is an element in broadening Treaty support and participation, thereby contributing to an early establishment and the efficient operation of the Treaty verification regime. The PTS will assist the States Signatories to facilitate and promote cooperation among themselves in the fullest exchange of information relating to verification-related technologies so that they may benefit from participation in the Treaty regime

  11. The nebular variables

    CERN Document Server

    Glasby, John S

    1974-01-01

    The Nebular Variables focuses on the nebular variables and their characteristics. Discussions are organized by type of nebular variable, namely, RW Aurigae stars, T Orionis stars, T Tauri stars, and peculiar nebular objects. Topics range from light variations of the stars to their spectroscopic and physical characteristics, spatial distribution, interaction with nebulosity, and evolutionary features. This volume is divided into four sections and consists of 25 chapters, the first of which provides general information on nebular variables, including their stellar associations and their classifi

  12. Ultrasonic variables affecting inspection

    International Nuclear Information System (INIS)

    Lautzenheiser, C.E.; Whiting, A.R.; McElroy, J.T.

    1977-01-01

    There are many variables which affect the detection of the effects and reproducibility of results when utilizing ultrasonic techniques. The most important variable is the procedure, as this document specifies, to a great extent, the controls that are exercised over the other variables. The most important variable is personnel with regards to training, qualification, integrity, data recording, and data analysis. Although the data is very limited, these data indicate that, if the procedure is carefully controlled, reliability of defect detection and reproducibility of results are both approximately 90 percent for reliability of detection, this applies to relatively small defects as reliability increases substantially as defect size increases above the recording limit. (author)

  13. The Significance of Loyalty on Consumer Credit Profitability

    OpenAIRE

    Aditya Galih Prihartono; Ujang Sumarwan; Noer Azam Achsani; Kirbrandoko

    2012-01-01

    The purpose of this research is to analyze and test the effect of customer loyalty on consumer credit profitability. Loyalty Index Score was developed to determine the level of customers’ loyalty level through 4 main variables; Longevity, Depth, Breadth and Referrals. The effect of Loyalty Index Score on profitability was further tested by path analysis to find out the significance direct relationship between loyalty and profitablity and the indirect relationship between the two variable th...

  14. Geophysical variables and behavior: XXI. Geomagnetic variation as possible enhancement stimuli for UFO reports preceding earthtremors.

    Science.gov (United States)

    Persinger, M A

    1985-02-01

    The contribution of geomagnetic variation to the occurrence of UFORs (reports of UFOs) within the New Madrid States during the 6-mo. increments before increases in the numbers of IV-V or less intensity earthquakes within the central USA was determined. Although statistically significant zero-order correlations existed between measures of earthquakes, UFORs and geomagnetic variability, the association between the latter two deteriorated markedly when their shared variance with earthquakes was held constant. These outcomes are compatible with the hypothesis that geomagnetic variability (or phenomena associated with it) may enhance UFORs but only if tectonic stress and strain are increasing within the region.

  15. Jesuits' Contribution to Meteorology.

    Science.gov (United States)

    Udías, Agustín

    1996-10-01

    Starting in the middle of the nineteenth century, as part of their scientific tradition, Jesuits founded a considerable number of meteorological observatories throughout the world. In many countries, Jesuits established and maintained the first meteorological stations during the period from 1860 to 1950. The Jesuits' most important contribution to atmospheric science was their pioneer work related to the study and forecast of tropical hurricanes. That research was carried out at observatories of Belén (Cuba), Manila (Philippines), and Zikawei (China). B. Viñes, M. Decheyrens, J. Aigué, and C.E. Deppermann stood out in this movement.

  16. Examining suicide: imaging's contributions.

    Science.gov (United States)

    Church, Elizabeth J

    2015-01-01

    For many people, the death of hope leads inexorably to the conclusion that the only viable solution, the only way to put an end to unendurable pain, is suicide. What leads a person to commit this final, desperate act, and how might we predict, intervene, and prevent suicide? Health care workers, including radiologic technologists, can play an important role in detecting warning signs in patients and in better understanding what factors may lead to suicide. Although certain forms of suicide such as suicide bombings and assisted suicide are beyond its scope, this article explores medical imaging's contributions to the study of this phenomenon.

  17. Red mud as a carbon sink: variability, affecting factors and environmental significance.

    Science.gov (United States)

    Si, Chunhua; Ma, Yingqun; Lin, Chuxia

    2013-01-15

    The capacity of red mud to sequester CO(2) varied markedly due to differences in bauxite type, processing and disposal methods. Calcium carbonates were the dominant mineral phases responsible for the carbon sequestration in the investigated red mud types. The carbon sequestration capacity of red mud was not fully exploited due to shortages of soluble divalent cations for formation of stable carbonate minerals. Titanate and silicate ions were the two major oxyanions that appeared to strongly compete with carbonate ions for the available soluble Ca. Supply of additional soluble Ca and Mg could be a viable pathway for maximizing carbon sequestration in red mud and simultaneously reducing the causticity of red mud. It is roughly estimated that over 100 million tonnes of CO(2) have been unintentionally sequestered in red mud around the world to date through the natural weathering of historically produced red mud. Based on the current production rate of red mud, it is likely that some 6 million tonnes of CO(2) will be sequestered annually through atmospheric carbonation. If appropriate technologies are in place for incorporating binding cations into red mud, approximately 6 million tonnes of additional CO(2) can be captured and stored in the red mud while the hazardousness of red mud is simultaneously reduced. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. School Choice, Gentrification, and the Variable Significance of Racial Stratification in Urban Neighborhoods

    Science.gov (United States)

    Pearman, Francis A., III; Swain, Walker A.

    2017-01-01

    Racial and socioeconomic stratification have long governed patterns of residential sorting in the American metropolis. However, recent expansions of school choice policies that allow parents to select schools outside their neighborhood raise questions as to whether this weakening of the neighborhood-school connection might influence the…

  19. Variable volume combustor

    Science.gov (United States)

    Ostebee, Heath Michael; Ziminsky, Willy Steve; Johnson, Thomas Edward; Keener, Christopher Paul

    2017-01-17

    The present application provides a variable volume combustor for use with a gas turbine engine. The variable volume combustor may include a liner, a number of micro-mixer fuel nozzles positioned within the liner, and a linear actuator so as to maneuver the micro-mixer fuel nozzles axially along the liner.

  20. Collective variables and dissipation

    International Nuclear Information System (INIS)

    Balian, R.

    1984-09-01

    This is an introduction to some basic concepts of non-equilibrium statistical mechanics. We emphasize in particular the relevant entropy relative to a given set of collective variables, the meaning of the projection method in the Liouville space, its use to establish the generalized transport equations for these variables, and the interpretation of dissipation in the framework of information theory

  1. Variability: A Pernicious Hypothesis.

    Science.gov (United States)

    Noddings, Nel

    1992-01-01

    The hypothesis of greater male variability in test results is discussed in its historical context, and reasons feminists have objected to the hypothesis are considered. The hypothesis acquires political importance if it is considered that variability results from biological, rather than cultural, differences. (SLD)

  2. Reinforcing Saccadic Amplitude Variability

    Science.gov (United States)

    Paeye, Celine; Madelain, Laurent

    2011-01-01

    Saccadic endpoint variability is often viewed as the outcome of neural noise occurring during sensorimotor processing. However, part of this variability might result from operant learning. We tested this hypothesis by reinforcing dispersions of saccadic amplitude distributions, while maintaining constant their medians. In a first experiment we…

  3. POVMs and hidden variables

    International Nuclear Information System (INIS)

    Stairs, Allen

    2007-01-01

    Recent results by Paul Busch and Adan Cabello claim to show that by appealing to POVMs, non-contextual hidden variables can be ruled out in two dimensions. While the results of Busch and Cabello are mathematically correct, interpretive problems render them problematic as no hidden variable proofs

  4. Interdependence Among Organizational Variables

    Science.gov (United States)

    Knowles, M. C.

    1975-01-01

    The interrelationship between a set of organizational variables was investigated at 14 work organizations within a company. The variables were production, quality, costs, job satisfaction of operatives, job satisfaction of supervisors, work anxiety, accidents, absence, labor turnover, and industrial unrest. (Author)

  5. Defined contribution health benefits.

    Science.gov (United States)

    Fronstin, P

    2001-03-01

    This Issue Brief discusses the emerging issue of "defined contribution" (DC) health benefits. The term "defined contribution" is used to describe a wide variety of approaches to the provision of health benefits, all of which have in common a shift in the responsibility for payment and selection of health care services from employers to employees. DC health benefits often are mentioned in the context of enabling employers to control their outlay for health benefits by avoiding increases in health care costs. DC health benefits may also shift responsibility for choosing a health plan and the associated risks of choosing a plan from employers to employees. There are three primary reasons why some employers currently are considering some sort of DC approach. First, they are once again looking for ways to keep their health care cost increases in line with overall inflation. Second, some employers are concerned that the public "backlash" against managed care will result in new legislation, regulations, and litigation that will further increase their health care costs if they do not distance themselves from health care decisions. Third, employers have modified not only most employee benefit plans, but labor market practices in general, by giving workers more choice, control, and flexibility. DC-type health benefits have existed as cafeteria plans since the 1980s. A cafeteria plan gives each employee the opportunity to determine the allocation of his or her total compensation (within employer-defined limits) among various employee benefits (primarily retirement or health). Most types of DC health benefits currently being discussed could be provided within the existing employment-based health insurance system, with or without the use of cafeteria plans. They could also allow employees to purchase health insurance directly from insurers, or they could drive new technologies and new forms of risk pooling through which health care services are provided and financed. DC health

  6. Contributing to Functionality

    DEFF Research Database (Denmark)

    Törpel, Bettina

    2006-01-01

    The objective of this paper is the design of computer supported joint action spaces. It is argued against a view of functionality as residing in computer applications. In such a view the creation of functionality is equivalent to the creation of computer applications. Functionality, in the view...... advocated in this paper, emerges in the specific dynamic interplay of actors, objectives, structures, practices and means. In this view, functionality is the result of creating, harnessing and inhabiting computer supported joint action spaces. The successful creation and further development of a computer...... supported joint action space comprises a whole range of appropriate design contributions. The approach is illustrated by the example of the creation of the computer supported joint action space "exchange network of voluntary union educators". As part of the effort a group of participants created...

  7. Contributing from the margins

    DEFF Research Database (Denmark)

    Chimirri, Niklas Alexander

    empirical study, I focused on kindergarten children’s first-person perspectives on the electronic media technologies they deemed subjectively relevant for conducting everyday life in the practice of their kindergarten. The concept of the children’s perspectives opens possibilities for transcending...... of the practice researcher when engaging with her/his potential co-researchers and the investigated, socio-materially mediated practice. The paper will argue that making sense of first-person perspectives – here on conducting a life with media technologies – presupposes that the researcher conceptualizes him....../herself as a contributor to an investigated practice, as inextricably entangled with the conducts of life of the others in relation to the conditions in practice. Doing research in the kindergarten thus becomes a mutual and collective endeavor, to which pedagogues, parents, children, and the researcher contribute. Even...

  8. Adaptive significance of root grafting in trees

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.; Jones, R.

    1988-12-31

    Root grafting has long been observed in forest trees but the adaptive significance of this trait has not been fully explained. Various authors have proposed that root grafting between trees contributes to mechanical support by linking adjacent root systems. Keeley proposes that this trait would be of greatest advantage in swamps where soils provide poor mechanical support. He provides as evidence a greenhouse study of Nyssa sylvatica Marsh in which seedlings of swamp provenance formed between-individual root grafts more frequently than upland provenance seedlings. In agreement with this within-species study, Keeley observed that arid zone species rarely exhibit grafts. Keeley also demonstrated that vines graft less commonly than trees, and herbs never do. Since the need for mechanical support coincides with this trend, these data seem to support his model. In this paper, the authors explore the mechanisms and ecological significance of root grafting, leading to predictions of root grafting incidence. Some observations support and some contradict the mechanical support hypothesis.

  9. Global warming: the significance of methane

    International Nuclear Information System (INIS)

    Dessus, B.; Le Treut, H.; Laponche, B.

    2008-01-01

    the concept of Global Warming Potential (GWP) indicates the relative contribution to global warming over a given period (for example 100 years) of a pulse emission at the start of the period of 1 kg of a specific greenhouse gas (GHG) in comparison to the contribution, over the same period, of an emission of 1 kg of CO 2 . The GWPs calculated for different time intervals take into account the differences in atmospheric lifetimes of the different GHGs. Using the '100-year GWP' to measure non CO 2 GHG emissions is not well suited to the case of permanent or long lifetime measures whose effectiveness is to be assessed at a given time horizon. In this context, it contributes to significantly playing down the importance of reducing emissions of GHGs with short atmospheric lifetimes. Thus, for example, methane which is not emitted over the period 2020- 2100 as a result of a landfill site being closed in 2020 will have an impact (as opposed to if the site remained in operation) that would be far greater towards 2100 compared to a CO 2 emission source that has also been stopped permanently and whose climate impact is measured in an equivalent manner. Using the GWP is only appropriate if applied year after year to time horizons considered to be of concern or decisive by climate studies, thus in particular 2050, 2100 and 2150. This is all the more significant as climate experts' current concerns lead them not only to advocate long-term stabilisation of GHG concentrations but also to avoid as far as possible intermediate excess of these concentrations over the coming century. Finally, it is noted that CH 4 prevention policies implemented in the short term may continue to have a long-term impact greater than merely taking into account the current GWP would imply. To more or less ignore the impact of CH 4 as it is unsuitable for accounting purposes affects the exclusive character of the link that may exist between the issue of GHGs and that of energy. Furthermore, if the

  10. Environmental variables, pesticide pollution and meiofaunal ...

    African Journals Online (AJOL)

    Due to the much smaller catchment of the Rooiels Estuary, many environmental variables were significantly different (p< 0.001) from the variables in the Lourens Estuary, e.g. salinity, temperature, pH, total suspended solids, nitrate and depth. No pesticide concentrations were expected in the Rooiels Estuary due

  11. HEALTH INSURANCE: FIXED CONTRIBUTION AND REIMBURSEMENT MAXIMA

    CERN Document Server

    Human Resources Division

    2001-01-01

    Affected by the salary adjustments on 1 January 2001 and the evolution of the staff members and fellows population, the average reference salary, which is used as an index for fixed contributions and reimbursement maxima, has changed significantly. An adjustment of the amounts of the reimbursement maxima and the fixed contributions is therefore necessary, as from 1 January 2001. Reimbursement maxima The revised reimbursement maxima will appear on the leaflet summarizing the benefits for the year 2001, which will be sent out with the forthcoming issue of the CHIS Bull'. This leaflet will also be available from the divisional secretariats and from the UNIQA office at CERN. Fixed contributions The fixed contributions, applicable to some categories of voluntarily insured persons, are set as follows (amounts in CHF for monthly contributions) : voluntarily insured member of the personnel, with normal health insurance cover : 910.- (was 815.- in 2000) voluntarily insured member of the personnel, with reduced heal...

  12. HEALTH INSURANCE: CONTRIBUTIONS AND REIMBURSEMENT MAXIMAL

    CERN Document Server

    HR Division

    2000-01-01

    Affected by both the salary adjustment index on 1.1.2000 and the evolution of the staff members and fellows population, the average reference salary, which is used as an index for fixed contributions and reimbursement maximal, has changed significantly. An adjustment of the amounts of the reimbursement maximal and the fixed contributions is therefore necessary, as from 1 January 2000.Reimbursement maximalThe revised reimbursement maximal will appear on the leaflet summarising the benefits for the year 2000, which will soon be available from the divisional secretariats and from the AUSTRIA office at CERN.Fixed contributionsThe fixed contributions, applicable to some categories of voluntarily insured persons, are set as follows (amounts in CHF for monthly contributions):voluntarily insured member of the personnel, with complete coverage:815,- (was 803,- in 1999)voluntarily insured member of the personnel, with reduced coverage:407,- (was 402,- in 1999)voluntarily insured no longer dependent child:326,- (was 321...

  13. The contribution of technology to added value

    CERN Document Server

    Fernandes, António S C

    2013-01-01

    There is a wide consensus that introduction of technology to the production process contributes to an overall economic value, however, confusion between technology, knowledge and capital often makes value calculations ambiguous and non-objective. The Contribution of Technology to Added Value addresses not only this issue of definition but also provides a production model to assess the value contribution of technology within the production process. A clarification  of fundamental semantics  provides a significant taxonomy for technology dependence, and allows understanding and modeling of how knowledge, technology and capital individually contribute to production and to value adding. A new technology dependence taxonomy is proposed and assessed following chapters explaining growth models, the KTC model and technology index values. Balancing theoretical knowledge with real-world data and applications The Contribution of Technology to Added Value clarifies the issue of value adding for a range of different vie...

  14. Effects of climate variability on global scale flood risk

    Science.gov (United States)

    Ward, P.; Dettinger, M. D.; Kummu, M.; Jongman, B.; Sperna Weiland, F.; Winsemius, H.

    2013-12-01

    In this contribution we demonstrate the influence of climate variability on flood risk. Globally, flooding is one of the worst natural hazards in terms of economic damages; Munich Re estimates global losses in the last decade to be in excess of $240 billion. As a result, scientifically sound estimates of flood risk at the largest scales are increasingly needed by industry (including multinational companies and the insurance industry) and policy communities. Several assessments of global scale flood risk under current and conditions have recently become available, and this year has seen the first studies assessing how flood risk may change in the future due to global change. However, the influence of climate variability on flood risk has as yet hardly been studied, despite the fact that: (a) in other fields (drought, hurricane damage, food production) this variability is as important for policy and practice as long term change; and (b) climate variability has a strong influence in peak riverflows around the world. To address this issue, this contribution illustrates the influence of ENSO-driven climate variability on flood risk, at both the globally aggregated scale and the scale of countries and large river basins. Although it exerts significant and widespread influences on flood peak discharges in many parts of the world, we show that ENSO does not have a statistically significant influence on flood risk once aggregated to global totals. At the scale of individual countries, though, strong relationships exist over large parts of the Earth's surface. For example, we find particularly strong anomalies of flood risk in El Niño or La Niña years (compared to all years) in southern Africa, parts of western Africa, Australia, parts of Central Eurasia (especially for El Niño), the western USA (especially for La Niña), and parts of South America. These findings have large implications for both decadal climate-risk projections and long-term future climate change

  15. Methane dynamics in Northern Wetlands: Significance of vascular plants

    Energy Technology Data Exchange (ETDEWEB)

    Joabsson, Anna

    2001-09-01

    The studies presented illustrate several different aspects of the impact of vascular plants on methane emissions from northern natural wetlands. The subject has been approached on different scales, ranging from the study of microbial substrates in the vicinity of a single plant root, to an attempt to extrapolate some of the results to the entire northern hemisphere north of 50 meridian. The main overall conclusions from the papers are that vascular plants affect net methane emissions 1) by offering an efficient route of transport to the atmosphere so that methane oxidation in oxic surface soils is avoided, and 2) by being sources of methanogenic substrate. The degree to which vascular wetland plants affect methane emissions seems to be dependent on species-specific differences in both the capacity to act as gas conduits and the exudation of labile carbon compounds to the soil. An intimate coupling between vascular plant production and methane emission was found in an Arctic tundra wetland, although other environmental variables (water table, temperature) also contributed significantly to the explained variation in methane exchange. Studies of vascular plant extidation of organic acids suggest that the available pool of methanogenic substrates is both qualitatively and quantitatively correlated to vascular plant production (photosynthetic rate). On global scales, vascular plant production as a single factor does not seem to be sufficient to explain the majority of variation in methane flux patterns. Based on comparable experiments at five different sites in the northwestern Eurasian and Greenlandic North, we suggest that mean seasonal soil temperature is the best predictor of methane exchange on broad spatial and temporal scales.

  16. Occurrence and significance of blueschist in the southern Lachlan Orogen

    International Nuclear Information System (INIS)

    Spaggiari, C.V.; Gray, D.R.; Foster, D.A.; Fanning, C.M.

    2002-01-01

    Serpentinite/talc-matrix melanges, bearing blocks of blueschist metavolcanics, occur within the Heathcote and Governor Fault Zones of the southern Lachlan Orogen. In the Heathcote Fault Zone, serpentinite-matrix melange consists of blocks or small pods of boninite, andesite, ultramafic rocks, chert and volcanogenic sandstone variably metamorphosed to prehnite-pumpellyite, greenschist, or greenschist to blueschist facies. In the Governor Fault Zone, blueschist metavolcanics occur as blocks within serpentinite/talc matrix that is interleaved with prehnite-pumpellyite to greenschist facies, intermediate pressure slate and phyllite. Ar/Ar dating of white mica from slaty mud-matrix (broken formation) indicates that the main fabric development occurred at 446 ± 2 Ma. U-Pb (SHRIMP) dating of titanite from blueschists in the Governor Fault Zone indicates that metamorphism occurred at approximately 450 Ma, close to the time of melange formation. Previously published, Ar/Ar dating of white mica from phyllite and biotite from metadiorite in the Heathcote Fault Zone suggest that blueschist metamorphism occurred at a similar time. These ages are supported by field relationships. Illite crystallinity and b 0 data from white mica, and the preservation of blueschist blocks indicate that these fault zones maintained low temperatures both during and after intermediate- to high-pressure metamorphism. Occurrences of blueschists in the Arthur Lineament of the Tyennan (Delamerian) Orogen in Tasmania, and in the New England Orogen, have different ages, and in conjunction with the occurrences described here, suggest that subduction-accretion processes contributed significantly to the development of the Tasmanides from Cambrian through to Carboniferous times. Copyright (2002) Geological Society of Australia

  17. Social Support Contributes to Outcomes following Distal Radius Fractures

    Directory of Open Access Journals (Sweden)

    Caitlin J. Symonette

    2013-01-01

    Full Text Available Background. Distal radius fractures are the most common fracture of the upper extremity and cause variable disability. This study examined the role of social support in patient-reported pain and disability at one year following distal radius fracture. Methods. The Medical Outcomes Study Social Support Survey was administered to a prospective cohort of 291 subjects with distal radius fractures at their baseline visit. Pearson correlations and stepwise linear regression models (F-to-remove 0.10 were used to identify whether social support contributes to wrist fracture outcomes. The primary outcome of pain and disability at one year was measured using the Patient Rated Wrist Evaluation. Results. Most injuries were low energy (67.5% and were treated nonoperatively (71.9%. Pearson correlation analysis revealed that higher reported social support correlated with improved Patient Rated Wrist Evaluation scores at 1 year, r(n=181=-0.22, P<0.05. Of the subscales within the Social Support Survey, emotional/informational support explained a significant proportion of the variance in 1-year Patient Rated Wrist Evaluation scores, R2=4.7%, F (1, 181 = 9.98, P<0.05. Conclusion. Lower emotional/informational social support at the time of distal radius fracture contributes a small but significant percentage to patient-reported pain and disability outcomes.

  18. Rapidly variable relatvistic absorption

    Science.gov (United States)

    Parker, M.; Pinto, C.; Fabian, A.; Lohfink, A.; Buisson, D.; Alston, W.; Jiang, J.

    2017-10-01

    I will present results from the 1.5Ms XMM-Newton observing campaign on the most X-ray variable AGN, IRAS 13224-3809. We find a series of nine absorption lines with a velocity of 0.24c from an ultra-fast outflow. For the first time, we are able to see extremely rapid variability of the UFO features, and can link this to the X-ray variability from the inner accretion disk. We find a clear flux dependence of the outflow features, suggesting that the wind is ionized by increasing X-ray emission.

  19. Intraspecific chromosome variability

    Directory of Open Access Journals (Sweden)

    N Dubinin

    2010-12-01

    Full Text Available (Editorial preface. The publication is presented in order to remind us of one of dramatic pages of the history of genetics. It re-opens for the contemporary reader a comprehensive work marking the priority change from plant cytogenetics to animal cytogenetics led by wide population studies which were conducted on Drosophila polytene chromosomes. The year of the publication (1937 became the point of irretrievable branching between the directions of Old World and New World genetics connected with the problems of chromosome variability and its significance for the evolution of the species. The famous book of T. Dobzhansky (1937 was published by Columbia University in the US under the title “Genetics and the origin of species”, and in the shadow of this American ‘skybuilding’ all other works grew dim. It is remarkable that both Dobzhansky and Dubinin come to similar conclusions about the role of chromosomes in speciation. This is not surprising given that they both might be considered as representatives of the Russian genetic school, by their birth and education. Interestingly, Dobzhansky had never referred to the full paper of Dubinin et al. (1937, though a previous short communication in Nature (1936 was included together with all former papers on the related subject. In full, the volume of the original publication printed in the Biological Journal in Moscow comprised 47 pages, in that number 41 pages of the Russian text accompanied by 16 Figs, a table and reference list, and, above all, 6 pages of the English summary. This final part in English is now reproduced in the authors’ version with the only addition being the reference list in the originally printed form.

  20. Eternity Variables to Simulate Specifications

    NARCIS (Netherlands)

    Hesselink, WH; Boiten, EA; Moller, B

    2002-01-01

    Simulation of specifications is introduced as a unification and generalization of refinement mappings, history variables, forward simulations, prophecy variables, and backward simulations. Eternity variables are introduced as a more powerful alternative for prophecy variables and backward

  1. Mechanisms of flow and water mass variability in Denmark Strait

    Science.gov (United States)

    Moritz, Martin; Jochumsen, Kerstin; Quadfasel, Detlef; Mashayekh Poul, Hossein; Käse, Rolf H.

    2017-04-01

    The dense water export through Denmark Strait contributes significantly to the lower limb of the Atlantic Meridional Overturning Circulation. Overflow water is transported southwestward not only in the deep channel of the Strait, but also within a thin bottom layer on the Greenland shelf. The flow on the shelf is mainly weak and barotropic, exhibiting many recirculations, but may eventually contribute to the overflow layer in the Irminger Basin by spilling events in the northern Irminger Basin. Especially the circulation around Dohrn Bank and the Kangerdlussuaq Trough contribute to the shelf-basin exchange. Moored observations show the overflow in Denmark Strait to be stable during the last 20 years (1996-2016). Nevertheless, flow variability was noticed on time scales of eddies and beyond, i.e. on weekly and interannual scales. Here, we use a combination of mooring data and shipboard hydrographic and current data to address the dominant modes of variability in the overflow, which are (i) eddies, (ii) barotropic pulsations of the plume, (iii) lateral shifts of the plume core position, and (iv) variations in vertical extension, i.e. varying overflow thickness. A principle component analysis is carried out and related to variations in sea surface height and wind stress, derived from satellite measurements. Furthermore, a test for topographic waves is performed. Shelf contributions to the overflow core in the Irminger Basin are identified from measurements of temperature and salinity, as well as velocity, which were obtained during recent cruises in the region. The flow and water mass pattern obtained from the observational data is compared to simulations in a high resolution regional model (ROMS), where tracer release experiments and float deployments were carried out. The modelling results allow a separation between different atmospheric forcing modes (NAO+ vs NAO- situations), which impact the water mass distribution and alter the dense water pathways on the

  2. The WFCAM multiwavelength Variable Star Catalog

    Science.gov (United States)

    Ferreira Lopes, C. E.; Dékány, I.; Catelan, M.; Cross, N. J. G.; Angeloni, R.; Leão, I. C.; De Medeiros, J. R.

    2015-01-01

    Context. Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for a time-domain exploration of the NIR sky. Aims: We perform a comprehensive search for stellar variability using the optical-NIR multiband photometric data in the public Calibration Database of the WFCAM Science Archive (WSA), with the aim of contributing to the general census of variable stars and of extending the current scarce inventory of accurate NIR light curves for a number of variable star classes. Methods: Standard data-mining methods were applied to extract and fine-tune time-series data from the WSA. We introduced new variability indices designed for multiband data with correlated sampling, and applied them for preselecting variable star candidates, i.e., light curves that are dominated by correlated variations, from noise-dominated ones. Preselection criteria were established by robust numerical tests for evaluating the response of variability indices to the colored noise characteristic of the data. We performed a period search using the string-length minimization method on an initial catalog of 6551 variable star candidates preselected by variability indices. Further frequency analysis was performed on positive candidates using three additional methods in combination, in order to cope with aliasing. Results: We find 275 periodic variable stars and an additional 44 objects with suspected variability with uncertain periods or apparently aperiodic variation. Only 44 of these objects had been previously known, including 11 RR Lyrae stars on the outskirts of the globular cluster M 3 (NGC 5272). We provide a preliminary classification of the new variable stars that have well-measured light curves, but the variability types of a large number of objects remain ambiguous. We classify most of the new variables as contact binary stars, but we also find several pulsating stars, among which

  3. Confirming theoretical pay constructs of a variable pay scheme

    Directory of Open Access Journals (Sweden)

    Sibangilizwe Ncube

    2013-05-01

    Full Text Available Orientation: Return on the investment in variable pay programmes remains controversial because their cost versus contribution cannot be empirically justified. Research purpose: This study validates the findings of the model developed by De Swardt on the factors related to successful variable pay programmes. Motivation for the study: Many organisations blindly implement variable pay programmes without any means to assess the impact these programmes have on the company’s performance. This study was necessary to validate the findings of an existing instrument that validates the contribution of variable pay schemes. Research design, approach and method: The study was conducted using quantitative research. A total of 300 completed questionnaires from a non-purposive sample of 3000 participants in schemes across all South African industries were returned and analysed. Main findings: Using exploratory and confirmatory factor analysis, it was found that the validation instrument developed by De Swardt is still largely valid in evaluating variable pay schemes. The differences between the study and the model were reported. Practical/managerial implications: The study confirmed the robustness of an existing model that enables practitioners to empirically validate the use of variable pay plans. This model assists in the design and implementation of variable pay programmes that meet critical success factors. Contribution/value-add: The study contributed to the development of a measurement instrument that will assess whether a variable pay plan contributes to an organisation’s success.

  4. Contribution to postnonclassical psychopathology.

    Directory of Open Access Journals (Sweden)

    Quintino-Aires J.

    2014-09-01

    Full Text Available Any psychological paradigm needs a psychopathological system that helps professionals to describe and explain the behavioral expressions that deviate from “normal” (whether this term is used with the semantic property of statistical or ideal adaptations. In this work, I seek to present the system that I have been developing since 1998 among the psychologists at the Instituto Vegotsky de Lisboa (Vygotsky Institute of Lisbon, Portugal, to understand psychopathology with regard to the vygotskian approach. It was conceived and designed according to the work of Rita Mendes Leal and her contribution to socioemotional development theory, AR Luria’s systemic and dynamic theory of the human brain, the theory of Activity (dyatel’nost of AN Leont’ev, and the psychopathological German school of E Kraepelin, presented and disseminated in Portugal in the early twentieth century by Professor Sobral Cid. It is intended to be a proposal to colleagues who are interested in postnonclassical psychology and a request for arguments.

  5. Variable Attitude Test Stand

    Data.gov (United States)

    Federal Laboratory Consortium — The Variable Attitude Test Stand designed and built for testing of the V-22 tilt rotor aircraft propulsion system, is used to evaluate the effect of aircraft flight...

  6. Several complex variables

    International Nuclear Information System (INIS)

    Field, M.J.

    1976-01-01

    Topics discussed include the elementary of holomorphic functions of several complex variables; the Weierstrass preparation theorem; meromorphic functions, holomorphic line bundles and divisors; elliptic operators on compact manifolds; hermitian connections; the Hodge decomposition theorem. ( author)

  7. Variable-Rate Premiums

    Data.gov (United States)

    Pension Benefit Guaranty Corporation — These interest rates are used to value vested benefits for variable rate premium purposes as described in PBGC's regulation on Premium Rates (29 CFR Part 4006) and...

  8. Variable Pricing Feasibility Assessment

    National Research Council Canada - National Science Library

    2004-01-01

    ...) and Willard Bishop Consulting (Barrington, IL) to evaluate the practicality of using a variable pricing system within DeCA to maintain an average of 30 percent customer savings and lower appropriated fund costs...

  9. Evolution of variable stars

    International Nuclear Information System (INIS)

    Becker, S.A.

    1986-08-01

    Throughout the domain of the H R diagram lie groupings of stars whose luminosity varies with time. These variable stars can be classified based on their observed properties into distinct types such as β Cephei stars, δ Cephei stars, and Miras, as well as many other categories. The underlying mechanism for the variability is generally felt to be due to four different causes: geometric effects, rotation, eruptive processes, and pulsation. In this review the focus will be on pulsation variables and how the theory of stellar evolution can be used to explain how the various regions of variability on the H R diagram are populated. To this end a generalized discussion of the evolutionary behavior of a massive star, an intermediate mass star, and a low mass star will be presented. 19 refs., 1 fig., 1 tab

  10. The measure and significance of Bateman's principles.

    Science.gov (United States)

    Collet, Julie M; Dean, Rebecca F; Worley, Kirsty; Richardson, David S; Pizzari, Tommaso

    2014-05-07

    Bateman's principles explain sex roles and sexual dimorphism through sex-specific variance in mating success, reproductive success and their relationships within sexes (Bateman gradients). Empirical tests of these principles, however, have come under intense scrutiny. Here, we experimentally show that in replicate groups of red junglefowl, Gallus gallus, mating and reproductive successes were more variable in males than in females, resulting in a steeper male Bateman gradient, consistent with Bateman's principles. However, we use novel quantitative techniques to reveal that current methods typically overestimate Bateman's principles because they (i) infer mating success indirectly from offspring parentage, and thus miss matings that fail to result in fertilization, and (ii) measure Bateman gradients through the univariate regression of reproductive over mating success, without considering the substantial influence of other components of male reproductive success, namely female fecundity and paternity share. We also find a significant female Bateman gradient but show that this likely emerges as spurious consequences of male preference for fecund females, emphasizing the need for experimental approaches to establish the causal relationship between reproductive and mating success. While providing qualitative support for Bateman's principles, our study demonstrates how current approaches can generate a misleading view of sex differences and roles.

  11. Increased timing variability in schizophrenia and bipolar disorder.

    Directory of Open Access Journals (Sweden)

    Amanda R Bolbecker

    Full Text Available Theoretical and empirical evidence suggests that impaired time perception and the neural circuitry underlying internal timing mechanisms may contribute to severe psychiatric disorders, including psychotic and mood disorders. The degree to which alterations in temporal perceptions reflect deficits that exist across psychosis-related phenotypes and the extent to which mood symptoms contribute to these deficits is currently unknown. In addition, compared to schizophrenia, where timing deficits have been more extensively investigated, sub-second timing has been studied relatively infrequently in bipolar disorder. The present study compared sub-second duration estimates of schizophrenia (SZ, schizoaffective disorder (SA, non-psychotic bipolar disorder (BDNP, bipolar disorder with psychotic features (BDP, and healthy non-psychiatric controls (HC on a well-established time perception task using sub-second durations. Participants included 66 SZ, 37 BDNP, 34 BDP, 31 SA, and 73 HC who participated in a temporal bisection task that required temporal judgements about auditory durations ranging from 300 to 600 milliseconds. Timing variability was significantly higher in SZ, BDP, and BDNP groups compared to healthy controls. The bisection point did not differ across groups. These findings suggest that both psychotic and mood symptoms may be associated with disruptions in internal timing mechanisms. Yet unexpected findings emerged. Specifically, the BDNP group had significantly increased variability compared to controls, but the SA group did not. In addition, these deficits appeared to exist independent of current symptom status. The absence of between group differences in bisection point suggests that increased variability in the SZ and bipolar disorder groups are due to alterations in perceptual timing in the sub-second range, possibly mediated by the cerebellum, rather than cognitive deficits.

  12. Calculus of one variable

    CERN Document Server

    Grossman, Stanley I

    1986-01-01

    Calculus of One Variable, Second Edition presents the essential topics in the study of the techniques and theorems of calculus.The book provides a comprehensive introduction to calculus. It contains examples, exercises, the history and development of calculus, and various applications. Some of the topics discussed in the text include the concept of limits, one-variable theory, the derivatives of all six trigonometric functions, exponential and logarithmic functions, and infinite series.This textbook is intended for use by college students.

  13. Software Testing Requires Variability

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    2003-01-01

    Software variability is the ability of a software system or artefact to be changed, customized or configured for use in a particular context. Variability in software systems is important from a number of perspectives. Some perspectives rightly receive much attention due to their direct economic...... impact in software production. As is also apparent from the call for papers these perspectives focus on qualities such as reuse, adaptability, and maintainability....

  14. Suspended graphene variable capacitor

    OpenAIRE

    AbdelGhany, M.; Mahvash, F.; Mukhopadhyay, M.; Favron, A.; Martel, R.; Siaj, M.; Szkopek, T.

    2016-01-01

    The tuning of electrical circuit resonance with a variable capacitor, or varactor, finds wide application with the most important being wireless telecommunication. We demonstrate an electromechanical graphene varactor, a variable capacitor wherein the capacitance is tuned by voltage controlled deflection of a dense array of suspended graphene membranes. The low flexural rigidity of graphene monolayers is exploited to achieve low actuation voltage in an ultra-thin structure. Large arrays compr...

  15. Factors contributing to adolescent obesity.

    Science.gov (United States)

    Al-Kloub, Manal I; Froelicher, Erika S

    2009-06-01

    Obesity in children is a significant public health concern. The prevalence of overweight and obesity in Jordanian children, and adolescents has increased in the last decade. The consequences of obesity to health in childhood and adulthood have both medical, and economic cost to individuals and society. This paper reviews the factors that contribute to adolescent obesity and emphasizes behavioral and environmental factors. An individual's behaviors such as increased consumption of high caloric foods, increased sedentary activity while decreasing physical activity has been identified as key issues in the development of obesity. Additionally, the current environment in homes, schools, and neighborhoods tend to discourage a healthy lifestyle. A comprehensive approach that involves the whole community is the best strategy for preventing adolescent obesity. Nurses are in a unique position to provide leadership in developing programs for healthier lifestyle choices for adolescents' and adoption of these goals into their daily lives.

  16. Statistical identification of effective input variables

    International Nuclear Information System (INIS)

    Vaurio, J.K.

    1982-09-01

    A statistical sensitivity analysis procedure has been developed for ranking the input data of large computer codes in the order of sensitivity-importance. The method is economical for large codes with many input variables, since it uses a relatively small number of computer runs. No prior judgemental elimination of input variables is needed. The sceening method is based on stagewise correlation and extensive regression analysis of output values calculated with selected input value combinations. The regression process deals with multivariate nonlinear functions, and statistical tests are also available for identifying input variables that contribute to threshold effects, i.e., discontinuities in the output variables. A computer code SCREEN has been developed for implementing the screening techniques. The efficiency has been demonstrated by several examples and applied to a fast reactor safety analysis code (Venus-II). However, the methods and the coding are general and not limited to such applications

  17. Genetic Influence on Slope Variability in a Childhood Reflexive Attention Task.

    Directory of Open Access Journals (Sweden)

    Rebecca A Lundwall

    Full Text Available Individuals are not perfectly consistent, and interindividual variability is a common feature in all varieties of human behavior. Some individuals respond more variably than others, however, and this difference may be important to understanding how the brain works. In this paper, we explore genetic contributions to response time (RT slope variability on a reflexive attention task. We are interested in such variability because we believe it is an important part of the overall picture of attention that, if understood, has the potential to improve intervention for those with attentional deficits. Genetic association studies are valuable in discovering biological pathways of variability and several studies have found such associations with a sustained attention task. Here, we expand our knowledge to include a reflexive attention task. We ask whether specific candidate genes are associated with interindividual variability on a childhood reflexive attention task in 9-16 year olds. The genetic makers considered are on 11 genes: APOE, BDNF, CHRNA4, COMT, DRD4, HTR4, IGF2, MAOA, SLC5A7, SLC6A3, and SNAP25. We find significant associations with variability with markers on nine and we discuss the results in terms of neurotransmitters associated with each gene and the characteristics of the associated measures from the reflexive attention task.

  18. On which timescales do gas transfer velocities control North Atlantic CO2 flux variability?

    Science.gov (United States)

    Couldrey, Matthew P.; Oliver, Kevin I. C.; Yool, Andrew; Halloran, Paul R.; Achterberg, Eric P.

    2016-05-01

    The North Atlantic is an important basin for the global ocean's uptake of anthropogenic and natural carbon dioxide (CO2), but the mechanisms controlling this carbon flux are not fully understood. The air-sea flux of CO2, F, is the product of a gas transfer velocity, k, the air-sea CO2 concentration gradient, ΔpCO2, and the temperature- and salinity-dependent solubility coefficient, α. k is difficult to constrain, representing the dominant uncertainty in F on short (instantaneous to interannual) timescales. Previous work shows that in the North Atlantic, ΔpCO2 and k both contribute significantly to interannual F variability but that k is unimportant for multidecadal variability. On some timescale between interannual and multidecadal, gas transfer velocity variability and its associated uncertainty become negligible. Here we quantify this critical timescale for the first time. Using an ocean model, we determine the importance of k, ΔpCO2, and α on a range of timescales. On interannual and shorter timescales, both ΔpCO2 and k are important controls on F. In contrast, pentadal to multidecadal North Atlantic flux variability is driven almost entirely by ΔpCO2; k contributes less than 25%. Finally, we explore how accurately one can estimate North Atlantic F without a knowledge of nonseasonal k variability, finding it possible for interannual and longer timescales. These findings suggest that continued efforts to better constrain gas transfer velocities are necessary to quantify interannual variability in the North Atlantic carbon sink. However, uncertainty in k variability is unlikely to limit the accuracy of estimates of longer-term flux variability.

  19. CONTRIBUTION OF INDIRECT TAXES

    Directory of Open Access Journals (Sweden)

    CHIRCULESCU MARIA FELICIA

    2015-08-01

    Full Text Available The work is based on the fact that at any time and in any society, taxation is regarded as undesirable for all taxpayers. The existence and it's manifestation is justified, because the operation of any company involves costs that must be covered by sufficient resources. Since ancient times, each state has adopted its own tax system, more or less perfected, as the state has experienced a greater or lesser economic and military power At the base of this work stays the fact that tax systems are a key factor influencing the overall efficiency of the economy. They determine the size tendency to save, invest and work, influencing the increase in production and employment, which is essential sights integral economic strategy, making tax reform an important component of economic reform. This paper aims to analyze the indirect taxes and their contribution to the public revenues in Romania, the purpose paper contains an analysis based on statistical series as indirect taxation is where tax harmonization was possible. Through analyzes, the paper aims to provide answers to the problem of the contradiction between the growing need for budgetary revenues, which entails a continuous amplification and diversification of taxation, on the one hand, and the need to stimulate economic development, on the other hand. The harmonization of indirect taxation had been achieved since this touches the free movement of goods and the freedom to supply services, not being able to say the same thing about direct taxation, which is why the European Community Treaty does not specify expressly the alignment of direct taxation, considering that direct taxation is a matter of Internal Policies that, for a country free option.

  20. Attributing uncertainty in streamflow simulations due to variable inputs via the Quantile Flow Deviation metric

    Science.gov (United States)

    Shoaib, Syed Abu; Marshall, Lucy; Sharma, Ashish

    2018-06-01

    Every model to characterise a real world process is affected by uncertainty. Selecting a suitable model is a vital aspect of engineering planning and design. Observation or input errors make the prediction of modelled responses more uncertain. By way of a recently developed attribution metric, this study is aimed at developing a method for analysing variability in model inputs together with model structure variability to quantify their relative contributions in typical hydrological modelling applications. The Quantile Flow Deviation (QFD) metric is used to assess these alternate sources of uncertainty. The Australian Water Availability Project (AWAP) precipitation data for four different Australian catchments is used to analyse the impact of spatial rainfall variability on simulated streamflow variability via the QFD. The QFD metric attributes the variability in flow ensembles to uncertainty associated with the selection of a model structure and input time series. For the case study catchments, the relative contribution of input uncertainty due to rainfall is higher than that due to potential evapotranspiration, and overall input uncertainty is significant compared to model structure and parameter uncertainty. Overall, this study investigates the propagation of input uncertainty in a daily streamflow modelling scenario and demonstrates how input errors manifest across different streamflow magnitudes.

  1. Seasonal dimethylsulfoniopropionate (DMSP) variability in Dona Paula Bay

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, S.S.; Chinchkar, U.; Nair, S.; LokaBharathi, P.A.; Chandramohan, D.

    as producers of DMSP in Dona Paula bay. Dinoflagellates also contributed during the non-monsoon seasons. Another factor involved in the variability of DMSPt was DMSP utilizing bacteria, which ranged from 1 to 10% of the total heterotrophic count...

  2. Quantifying the Clinical Significance of Cannabis Withdrawal

    Science.gov (United States)

    Allsop, David J.; Copeland, Jan; Norberg, Melissa M.; Fu, Shanlin; Molnar, Anna; Lewis, John; Budney, Alan J.

    2012-01-01

    Background and Aims Questions over the clinical significance of cannabis withdrawal have hindered its inclusion as a discrete cannabis induced psychiatric condition in the Diagnostic and Statistical Manual of Mental Disorders (DSM IV). This study aims to quantify functional impairment to normal daily activities from cannabis withdrawal, and looks at the factors predicting functional impairment. In addition the study tests the influence of functional impairment from cannabis withdrawal on cannabis use during and after an abstinence attempt. Methods and Results A volunteer sample of 49 non-treatment seeking cannabis users who met DSM-IV criteria for dependence provided daily withdrawal-related functional impairment scores during a one-week baseline phase and two weeks of monitored abstinence from cannabis with a one month follow up. Functional impairment from withdrawal symptoms was strongly associated with symptom severity (p = 0.0001). Participants with more severe cannabis dependence before the abstinence attempt reported greater functional impairment from cannabis withdrawal (p = 0.03). Relapse to cannabis use during the abstinence period was associated with greater functional impairment from a subset of withdrawal symptoms in high dependence users. Higher levels of functional impairment during the abstinence attempt predicted higher levels of cannabis use at one month follow up (p = 0.001). Conclusions Cannabis withdrawal is clinically significant because it is associated with functional impairment to normal daily activities, as well as relapse to cannabis use. Sample size in the relapse group was small and the use of a non-treatment seeking population requires findings to be replicated in clinical samples. Tailoring treatments to target withdrawal symptoms contributing to functional impairment during a quit attempt may improve treatment outcomes. PMID:23049760

  3. Quantifying the clinical significance of cannabis withdrawal.

    Directory of Open Access Journals (Sweden)

    David J Allsop

    Full Text Available Questions over the clinical significance of cannabis withdrawal have hindered its inclusion as a discrete cannabis induced psychiatric condition in the Diagnostic and Statistical Manual of Mental Disorders (DSM IV. This study aims to quantify functional impairment to normal daily activities from cannabis withdrawal, and looks at the factors predicting functional impairment. In addition the study tests the influence of functional impairment from cannabis withdrawal on cannabis use during and after an abstinence attempt.A volunteer sample of 49 non-treatment seeking cannabis users who met DSM-IV criteria for dependence provided daily withdrawal-related functional impairment scores during a one-week baseline phase and two weeks of monitored abstinence from cannabis with a one month follow up. Functional impairment from withdrawal symptoms was strongly associated with symptom severity (p=0.0001. Participants with more severe cannabis dependence before the abstinence attempt reported greater functional impairment from cannabis withdrawal (p=0.03. Relapse to cannabis use during the abstinence period was associated with greater functional impairment from a subset of withdrawal symptoms in high dependence users. Higher levels of functional impairment during the abstinence attempt predicted higher levels of cannabis use at one month follow up (p=0.001.Cannabis withdrawal is clinically significant because it is associated with functional impairment to normal daily activities, as well as relapse to cannabis use. Sample size in the relapse group was small and the use of a non-treatment seeking population requires findings to be replicated in clinical samples. Tailoring treatments to target withdrawal symptoms contributing to functional impairment during a quit attempt may improve treatment outcomes.

  4. Partitioning inter annual variability in net ecosystem exchange between climatic variability and functional change

    International Nuclear Information System (INIS)

    Hui, D.; Luo, Y.; Katul, G.

    2003-01-01

    Inter annual variability in net ecosystem exchange of carbon is investigated using a homogeneity-of-slopes model to identify the function change contributing to inter annual variability, net ecosystem carbon exchange, and night-time ecosystem respiration. Results of employing this statistical approach to a data set collected at the Duke Forest AmeriFlux site from August 1997 to December 2001 are discussed. The results demonstrate that it is feasible to partition the variation in ecosystem carbon fluxes into direct effects of seasonal and inter annual climatic variability and functional change. 51 refs., 4 tabs., 5 figs

  5. Sparse modeling of spatial environmental variables associated with asthma.

    Science.gov (United States)

    Chang, Timothy S; Gangnon, Ronald E; David Page, C; Buckingham, William R; Tandias, Aman; Cowan, Kelly J; Tomasallo, Carrie D; Arndt, Brian G; Hanrahan, Lawrence P; Guilbert, Theresa W

    2015-02-01

    Geographically distributed environmental factors influence the burden of diseases such as asthma. Our objective was to identify sparse environmental variables associated with asthma diagnosis gathered from a large electronic health record (EHR) dataset while controlling for spatial variation. An EHR dataset from the University of Wisconsin's Family Medicine, Internal Medicine and Pediatrics Departments was obtained for 199,220 patients aged 5-50years over a three-year period. Each patient's home address was geocoded to one of 3456 geographic census block groups. Over one thousand block group variables were obtained from a commercial database. We developed a Sparse Spatial Environmental Analysis (SASEA). Using this method, the environmental variables were first dimensionally reduced with sparse principal component analysis. Logistic thin plate regression spline modeling was then used to identify block group variables associated with asthma from sparse principal components. The addresses of patients from the EHR dataset were distributed throughout the majority of Wisconsin's geography. Logistic thin plate regression spline modeling captured spatial variation of asthma. Four sparse principal components identified via model selection consisted of food at home, dog ownership, household size, and disposable income variables. In rural areas, dog ownership and renter occupied housing units from significant sparse principal components were associated with asthma. Our main contribution is the incorporation of sparsity in spatial modeling. SASEA sequentially added sparse principal components to Logistic thin plate regression spline modeling. This method allowed association of geographically distributed environmental factors with asthma using EHR and environmental datasets. SASEA can be applied to other diseases with environmental risk factors. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Variables associated with active spondylolysis.

    Science.gov (United States)

    Gregg, Chris D; Dean, Sarah; Schneiders, Anthony G

    2009-11-01

    Retrospective non-experimental study. To investigate variables associated with active spondylolysis. A retrospective study audited clinical data over a two year period from patients with suspected spondylolysis that were referred for a SPECT bone scan. Six exploratory variables were identified and analysed using uni- and multi-variate regression from 82 patient records to determine the association between symptomatic, physical and demographic characteristics, and the presence of an active spondylolysis. Tertiary level multidisciplinary private practice sports medicine clinic. All patients with low back pain that required a SPECT bone scan to confirm suspected spondylolysis. 82 subjects were included in the final sample group. The six exploratory variables included Age, Gender, Injury duration, Injury onset, Sports participation and the result of the Single Leg Hyperextension Test. The dependent outcome variable was the result of the SPECT bone scan (scan-positive or scan-negative). Adolescent males had a higher incidence of spondylolysis detected by SPECT bone scan compared to other patients and a statistically significant association was demonstrated for both age (p=0.01) and gender (p=0.01). Subjects with an active spondylolysis were nearly five times more likely to be male and aged less than 20 years. Furthermore, the likelihood ratio indicated that adolescent males with suspected spondylolysis were three and a half times more likely to have a positive bone scan result. The Single Leg Hyperextension Test did not demonstrate a statistically significant association with spondylolysis (p=0.47). Clinicians assessing for a predisposition to the development of spondylolysis should consider the gender and age of the patient and not rely on the predictive ability of the Single Leg Hyperextension Test.

  7. Pneumatic Variable Series Elastic Actuator.

    Science.gov (United States)

    Zheng, Hao; Wu, Molei; Shen, Xiangrong

    2016-08-01

    Inspired by human motor control theory, stiffness control is highly effective in manipulation and human-interactive tasks. The implementation of stiffness control in robotic systems, however, has largely been limited to closed-loop control, and suffers from multiple issues such as limited frequency range, potential instability, and lack of contribution to energy efficiency. Variable-stiffness actuator represents a better solution, but the current designs are complex, heavy, and bulky. The approach in this paper seeks to address these issues by using pneumatic actuator as a variable series elastic actuator (VSEA), leveraging the compressibility of the working fluid. In this work, a pneumatic actuator is modeled as an elastic element with controllable stiffness and equilibrium point, both of which are functions of air masses in the two chambers. As such, for the implementation of stiffness control in a robotic system, the desired stiffness/equilibrium point can be converted to the desired chamber air masses, and a predictive pressure control approach is developed to control the timing of valve switching to obtain the desired air mass while minimizing control action. Experimental results showed that the new approach in this paper requires less expensive hardware (on-off valve instead of proportional valve), causes less control action in implementation, and provides good control performance by leveraging the inherent dynamics of the actuator.

  8. Contributions to quantum probability

    International Nuclear Information System (INIS)

    Fritz, Tobias

    2010-01-01

    Chapter 1: On the existence of quantum representations for two dichotomic measurements. Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial dynamics. The solution uses methods from the theory of operator algebras and the theory of moment problems. The ensuing conditions reveal surprisingly simple relations between certain quantum-mechanical probabilities. It also shown that generally, none of these relations holds in general probabilistic models. This result might facilitate further experimental discrimination between quantum mechanics and other general probabilistic theories. Chapter 2: Possibilistic Physics. I try to outline a framework for fundamental physics where the concept of probability gets replaced by the concept of possibility. Whereas a probabilistic theory assigns a state-dependent probability value to each outcome of each measurement, a possibilistic theory merely assigns one of the state-dependent labels ''possible to occur'' or ''impossible to occur'' to each outcome of each measurement. It is argued that Spekkens' combinatorial toy theory of quantum mechanics is inconsistent in a probabilistic framework, but can be regarded as possibilistic. Then, I introduce the concept of possibilistic local hidden variable models and derive a class of possibilistic Bell inequalities which are violated for the possibilistic Popescu-Rohrlich boxes. The chapter ends with a philosophical discussion on possibilistic vs. probabilistic. It can be argued that, due to better falsifiability properties, a possibilistic theory has higher predictive power than a probabilistic one. Chapter 3: The quantum region for von Neumann measurements with postselection. It is determined under which conditions a probability distribution on a finite set can occur as the outcome

  9. Contributions to quantum probability

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Tobias

    2010-06-25

    Chapter 1: On the existence of quantum representations for two dichotomic measurements. Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial dynamics. The solution uses methods from the theory of operator algebras and the theory of moment problems. The ensuing conditions reveal surprisingly simple relations between certain quantum-mechanical probabilities. It also shown that generally, none of these relations holds in general probabilistic models. This result might facilitate further experimental discrimination between quantum mechanics and other general probabilistic theories. Chapter 2: Possibilistic Physics. I try to outline a framework for fundamental physics where the concept of probability gets replaced by the concept of possibility. Whereas a probabilistic theory assigns a state-dependent probability value to each outcome of each measurement, a possibilistic theory merely assigns one of the state-dependent labels ''possible to occur'' or ''impossible to occur'' to each outcome of each measurement. It is argued that Spekkens' combinatorial toy theory of quantum mechanics is inconsistent in a probabilistic framework, but can be regarded as possibilistic. Then, I introduce the concept of possibilistic local hidden variable models and derive a class of possibilistic Bell inequalities which are violated for the possibilistic Popescu-Rohrlich boxes. The chapter ends with a philosophical discussion on possibilistic vs. probabilistic. It can be argued that, due to better falsifiability properties, a possibilistic theory has higher predictive power than a probabilistic one. Chapter 3: The quantum region for von Neumann measurements with postselection. It is determined under which conditions a probability distribution on a

  10. Pulsating red variables

    International Nuclear Information System (INIS)

    Whitelock, P.A.

    1990-01-01

    The observational characteristics of pulsating red variables are reviewed with particular emphasis on the Miras. These variables represent the last stage in the evolution of stars on the Asymptotic Giant Branch (AGB). A large fraction of the IRAS sources in the Bulge are Mira variables and a subset of these are also OH/IR sources. Their periods range up to 720 days, though most are between 360 and 560 days. At a given period those stars with the highest pulsation amplitudes have the highest mass-loss rates; this is interpreted as evidence for a causal connection between mass-loss and pulsation. It is suggested that once an AGB star has become a Mira it will evolve with increasing pulsation amplitude and mass-loss, but with very little change of luminosity or logarithmic period. 26 refs

  11. Variable stator radial turbine

    Science.gov (United States)

    Rogo, C.; Hajek, T.; Chen, A. G.

    1984-01-01

    A radial turbine stage with a variable area nozzle was investigated. A high work capacity turbine design with a known high performance base was modified to accept a fixed vane stagger angle moveable sidewall nozzle. The nozzle area was varied by moving the forward and rearward sidewalls. Diffusing and accelerating rotor inlet ramps were evaluated in combinations with hub and shroud rotor exit rings. Performance of contoured sidewalls and the location of the sidewall split line with respect to the rotor inlet was compared to the baseline. Performance and rotor exit survey data are presented for 31 different geometries. Detail survey data at the nozzle exit are given in contour plot format for five configurations. A data base is provided for a variable geometry concept that is a viable alternative to the more common pivoted vane variable geometry radial turbine.

  12. Internal variables in thermoelasticity

    CERN Document Server

    Berezovski, Arkadi

    2017-01-01

    This book describes an effective method for modeling advanced materials like polymers, composite materials and biomaterials, which are, as a rule, inhomogeneous. The thermoelastic theory with internal variables presented here provides a general framework for predicting a material’s reaction to external loading. The basic physical principles provide the primary theoretical information, including the evolution equations of the internal variables. The cornerstones of this framework are the material representation of continuum mechanics, a weak nonlocality, a non-zero extra entropy flux, and a consecutive employment of the dissipation inequality. Examples of thermoelastic phenomena are provided, accompanied by detailed procedures demonstrating how to simulate them.

  13. Resiliencia y variables sociodemograficas

    OpenAIRE

    Calero Martinez, Edgar David

    2015-01-01

    En el presente trabajo se aborda la definición de una de las variables dentro de lo que se denomina Capital psicológico positivo, la Resiliencia, sus principales características y algunas de las variables socio demográficas que en el estudio pretenden ver el nivel de relación existente entre cada una de ellas (indirecta o directamente) en el proceso resiliente de una persona para posteriores discusiones y su implicación dentro de la gestión empresarial y sus direcciones futuras.

  14. Risk assessment of groundwater level variability using variable Kriging methods

    Science.gov (United States)

    Spanoudaki, Katerina; Kampanis, Nikolaos A.

    2015-04-01

    Assessment of the water table level spatial variability in aquifers provides useful information regarding optimal groundwater management. This information becomes more important in basins where the water table level has fallen significantly. The spatial variability of the water table level in this work is estimated based on hydraulic head measured during the wet period of the hydrological year 2007-2008, in a sparsely monitored basin in Crete, Greece, which is of high socioeconomic and agricultural interest. Three Kriging-based methodologies are elaborated in Matlab environment to estimate the spatial variability of the water table level in the basin. The first methodology is based on the Ordinary Kriging approach, the second involves auxiliary information from a Digital Elevation Model in terms of Residual Kriging and the third methodology calculates the probability of the groundwater level to fall below a predefined minimum value that could cause significant problems in groundwater resources availability, by means of Indicator Kriging. The Box-Cox methodology is applied to normalize both the data and the residuals for improved prediction results. In addition, various classical variogram models are applied to determine the spatial dependence of the measurements. The Matérn model proves to be the optimal, which in combination with Kriging methodologies provides the most accurate cross validation estimations. Groundwater level and probability maps are constructed to examine the spatial variability of the groundwater level in the basin and the associated risk that certain locations exhibit regarding a predefined minimum value that has been set for the sustainability of the basin's groundwater resources. Acknowledgement The work presented in this paper has been funded by the Greek State Scholarships Foundation (IKY), Fellowships of Excellence for Postdoctoral Studies (Siemens Program), 'A simulation-optimization model for assessing the best practices for the

  15. Examining Impulse-Variability in Kicking.

    Science.gov (United States)

    Chappell, Andrew; Molina, Sergio L; McKibben, Jonathon; Stodden, David F

    2016-07-01

    This study examined variability in kicking speed and spatial accuracy to test the impulse-variability theory prediction of an inverted-U function and the speed-accuracy trade-off. Twenty-eight 18- to 25-year-old adults kicked a playground ball at various percentages (50-100%) of their maximum speed at a wall target. Speed variability and spatial error were analyzed using repeated-measures ANOVA with built-in polynomial contrasts. Results indicated a significant inverse linear trajectory for speed variability (p < .001, η2= .345) where 50% and 60% maximum speed had significantly higher variability than the 100% condition. A significant quadratic fit was found for spatial error scores of mean radial error (p < .0001, η2 = .474) and subject-centroid radial error (p < .0001, η2 = .453). Findings suggest variability and accuracy of multijoint, ballistic skill performance may not follow the general principles of impulse-variability theory or the speed-accuracy trade-off.

  16. Interannual variability of sea surface temperature and circulation in ...

    African Journals Online (AJOL)

    Local surface heat flux exchanges driven by the anomalous shortwave radiation dominated the interannual SST variability in the Tanzanian shelf region, with some contribution by the advection of heat anomalies from the North-East Madagascar Current. Farther offshore, the interannual variability of the SST was dominated ...

  17. Factors Contributing to Personal Commitment in Chinese Interethnic Couples

    Directory of Open Access Journals (Sweden)

    Xinmiao Zhong

    2014-06-01

    Full Text Available Interethnic relationships are increasingly common in many societies, yet interethnic couples have a higher divorce rate compared to intraethnic couples. Given these facts and the dearth of research, this study aimed to identify factors that contribute to couples’ commitment in interethnic relationships. This study investigated the personal commitment of Chinese interethnic couples in the United Kingdom and the United States. Specifically, whether love, dyadic adjustment and “couple cultural identity” (i.e. acculturation to the partner and couple’s similarity on individualism/collectivism would predict personal commitment and whether each variable would account for unique variance in personal commitment of the participants. Thirty-seven Chinese/non-Chinese heterosexual couples participated in the study and significant relationships between love and personal commitment, dyadic adjustment and personal commitment were found. Also, couple cultural identity was important for women’s personal commitment. Multiple regression and structural equation modelling showed that partners in interethnic relationships defined personal commitment in different ways with men emphasizing love and dyadic adjustment, and women emphasizing love and acculturation to their partner. The discovery of the importance of couple cultural identity in contributing to personal commitment, besides love and dyadic adjustment, helps researchers to gain a greater understanding of such relationships and to extend the research on interethnic relationships.

  18. Soil Microbial Community Contribution to Small Headwater Stream Metabolism.

    Science.gov (United States)

    Clapcott, J. E.; Gooderham, J. P.; Barmuta, L. A.; Davies, P. E.

    2005-05-01

    The temporal dynamics of sediment respiration were examined in seven small headwater streams in forested catchments in 2004. A strong seasonal response was observed with higher respiration rates in depositional zones than in gravel runs. The data were also examined in the context of proportional habitat distributions that highlighted the importance of high flow events in shaping whole stream metabolic budgets. This study specifically examines the question of terrestrial soil respiration contribution to whole stream metabolism by the controlled inundation of terrestrial soils. The experiment included six experimentally inundated terrestrial zones, six terrestrial controls, and six in-stream depositional zones. Sediment bacterial respiration was measured using 14C leucine incorporation and cotton strip bioassays were also employed to provide an indicative measure of sediment microbial activity. Despite high variability and exhibiting significantly lower bacterial activity than in-stream sediments, modelling using flow data and habitat mapping illustrated the important contribution of terrestrial soil respiration to the whole stream metabolic budgets of small headwater streams. In addition, microbial community composition examined using phospholipid fatty acid analysis clearly differentiated between terrestrial and aquatic communities. Freshly inundated terrestrial communities remained similar to un-inundated controls after 28 days.

  19. Reliability-Based Robust Design Optimization of Structures Considering Uncertainty in Design Variables

    Directory of Open Access Journals (Sweden)

    Shujuan Wang

    2015-01-01

    Full Text Available This paper investigates the structural design optimization to cover both the reliability and robustness under uncertainty in design variables. The main objective is to improve the efficiency of the optimization process. To address this problem, a hybrid reliability-based robust design optimization (RRDO method is proposed. Prior to the design optimization, the Sobol sensitivity analysis is used for selecting key design variables and providing response variance as well, resulting in significantly reduced computational complexity. The single-loop algorithm is employed to guarantee the structural reliability, allowing fast optimization process. In the case of robust design, the weighting factor balances the response performance and variance with respect to the uncertainty in design variables. The main contribution of this paper is that the proposed method applies the RRDO strategy with the usage of global approximation and the Sobol sensitivity analysis, leading to the reduced computational cost. A structural example is given to illustrate the performance of the proposed method.

  20. Several real variables

    CERN Document Server

    Kantorovitz, Shmuel

    2016-01-01

    This undergraduate textbook is based on lectures given by the author on the differential and integral calculus of functions of several real variables. The book has a modern approach and includes topics such as: •The p-norms on vector space and their equivalence •The Weierstrass and Stone-Weierstrass approximation theorems •The differential as a linear functional; Jacobians, Hessians, and Taylor's theorem in several variables •The Implicit Function Theorem for a system of equations, proved via Banach’s Fixed Point Theorem •Applications to Ordinary Differential Equations •Line integrals and an introduction to surface integrals This book features numerous examples, detailed proofs, as well as exercises at the end of sections. Many of the exercises have detailed solutions, making the book suitable for self-study. Several Real Variables will be useful for undergraduate students in mathematics who have completed first courses in linear algebra and analysis of one real variable.

  1. Variability in GPS sources

    NARCIS (Netherlands)

    Jauncey, DL; King, EA; Bignall, HE; Lovell, JEJ; Kedziora-Chudczer, L; Tzioumis, AK; Tingay, SJ; Macquart, JP; McCulloch, PM

    2003-01-01

    Flux density monitoring data at 2.3 and 8.4 GHz is presented for a sample of 33 southern hemisphere GPS sources, drawn from the 2.7 GHz Parkes survey. This monitoring data, together with VLBI monitoring data, shows that a small fraction of these sources, similar to10%, vary. Their variability falls

  2. All Those Independent Variables.

    Science.gov (United States)

    Meacham, Merle L.

    This paper presents a case study of a sixth grade remedial math class which illustrates the thesis that only the "experimental attitude," not the "experimental method," is appropriate in the classroom. The thesis is based on the fact that too many independent variables exist in a classroom situation to allow precise measurement. The case study…

  3. Variable speed generators

    CERN Document Server

    Boldea, Ion

    2005-01-01

    With the deregulation of electrical energy production and distribution, says Boldea (Polytechnical Institute, Timisoara, Romania) producers are looking for ways to tailor their electricity for different markets. Variable-speed electric generators are serving that purpose, up to the 400 megavolt ampere unit size, in Japan since 1996 and Germany sinc

  4. Surfing wave climate variability

    Science.gov (United States)

    Espejo, Antonio; Losada, Iñigo J.; Méndez, Fernando J.

    2014-10-01

    International surfing destinations are highly dependent on specific combinations of wind-wave formation, thermal conditions and local bathymetry. Surf quality depends on a vast number of geophysical variables, and analyses of surf quality require the consideration of the seasonal, interannual and long-term variability of surf conditions on a global scale. A multivariable standardized index based on expert judgment is proposed for this purpose. This index makes it possible to analyze surf conditions objectively over a global domain. A summary of global surf resources based on a new index integrating existing wave, wind, tides and sea surface temperature databases is presented. According to general atmospheric circulation and swell propagation patterns, results show that west-facing low to middle-latitude coasts are more suitable for surfing, especially those in the Southern Hemisphere. Month-to-month analysis reveals strong seasonal variations in the occurrence of surfable events, enhancing the frequency of such events in the North Atlantic and the North Pacific. Interannual variability was investigated by comparing occurrence values with global and regional modes of low-frequency climate variability such as El Niño and the North Atlantic Oscillation, revealing their strong influence at both the global and the regional scale. Results of the long-term trends demonstrate an increase in the probability of surfable events on west-facing coasts around the world in recent years. The resulting maps provide useful information for surfers, the surf tourism industry and surf-related coastal planners and stakeholders.

  5. Hardness variability in commercial technologies

    International Nuclear Information System (INIS)

    Shaneyfelt, M.R.; Winokur, P.S.; Meisenheimer, T.L.; Sexton, F.W.; Roeske, S.B.; Knoll, M.G.

    1994-01-01

    The radiation hardness of commercial Floating Gate 256K E 2 PROMs from a single diffusion lot was observed to vary between 5 to 25 krad(Si) when irradiated at a low dose rate of 64 mrad(Si)/s. Additional variations in E 2 PROM hardness were found to depend on bias condition and failure mode (i.e., inability to read or write the memory), as well as the foundry at which the part was manufactured. This variability is related to system requirements, and it is shown that hardness level and variability affect the allowable mode of operation for E 2 PROMs in space applications. The radiation hardness of commercial 1-Mbit CMOS SRAMs from Micron, Hitachi, and Sony irradiated at 147 rad(Si)/s was approximately 12, 13, and 19 krad(Si), respectively. These failure levels appear to be related to increases in leakage current during irradiation. Hardness of SRAMs from each manufacturer varied by less than 20%, but differences between manufacturers are significant. The Qualified Manufacturer's List approach to radiation hardness assurance is suggested as a way to reduce variability and to improve the hardness level of commercial technologies

  6. Adolescents' Perceptions of Their Fathers' Involvement: Significance to School Attitudes.

    Science.gov (United States)

    Flouri, Eirini; Buchanan, Ann; Bream, Victoria

    2002-01-01

    Based on data from 2,722 British adolescents, this study explores whether perceived father involvement can be associated with school attitudes. Multiple regression analysis showed that both father involvement and mother involvement contributed significantly and independently to positive school attitudes. Furthermore, the association between father…

  7. Supporting experts to handle tweet collections about significant events

    NARCIS (Netherlands)

    Hürriyetoglu, Ali; Oostdijk, Nelleke; Basar, Erkan; van den Bosch, A.; Frasincar, F.; Ittoo, A.; Nguyen, L.; Metais, E.

    2017-01-01

    We introduce Relevancer that processes a tweet set and enables generating an automatic classifier from it. Relevancer satisfies information needs of experts during significant events. Enabling experts to combine automatic procedures with expertise is the main contribution of our approach and the

  8. Biological, ecological and agronomic significance of plant phenolic ...

    African Journals Online (AJOL)

    Our understanding of some phenolic compounds in the last few decades has greatly improved. However, their biological, ecological and agronomical significance in the rhizosphere of most symbiotic legumes is much less clear. Further understanding of these biomolecules will increase our knowledge of their contribution in ...

  9. RADIO VARIABILITY IN SEYFERT NUCLEI

    International Nuclear Information System (INIS)

    Mundell, C. G.; Ferruit, P.; Nagar, N.; Wilson, A. S.

    2009-01-01

    Comparison of 8.4 GHz radio images of a sample of eleven, early-type Seyfert galaxies with previous observations reveals possible variation in the nuclear radio flux density in five of them over a seven year period. Four Seyferts (NGC 2110, NGC 3081, MCG -6-30-15, and NGC 5273) show a decline in their 8.4 GHz nuclear flux density between 1992 and 1999, while one (NGC 4117) shows an increase; the flux densities of the remaining six Seyferts (Mrk 607, NGC 1386, Mrk 620, NGC 3516, NGC 4968, and NGC 7465) have remained constant over this period. New images of MCG -5-23-16 are also presented. We find no correlation between radio variability and nuclear radio luminosity or Seyfert nuclear type, although the sample is small and dominated by type 2 Seyferts. Instead, a possible correlation between the presence of nuclear radio variability and the absence of hundred parsec-scale radio emission is seen, with four out of five marginally resolved or unresolved nuclei showing a change in nuclear flux density, while five out of six extended sources show no nuclear variability despite having unresolved nuclear sources. NGC 2110 is the only source in our sample with significant extended radio structure and strong nuclear variability (∼38% decline in nuclear flux density over seven years). The observed nuclear flux variability indicates significant changes are likely to have occurred in the structure of the nucleus on scales smaller than the VLA beam size (i.e., within the central ∼0.''1 (15 pc)), between the two epochs, possibly due to the appearance and fading of new components or shocks in the jet, consistent with previous detection of subparsec-scale nuclear structure in this Seyfert. Our results suggest that all Seyferts may exhibit variation in their nuclear radio flux density at 8.4 GHz, but that variability is more easily recognized in compact sources in which emission from the variable nucleus is not diluted by unresolved, constant flux density radio jet emission

  10. Librarian contributions to clinical practice guidelines.

    Science.gov (United States)

    Cruse, Peggy; Protzko, Shandra

    2014-01-01

    Librarians have become more involved in developing high quality systematic reviews. Evidence-based practice guidelines are an extension of systematic reviews and offer another significant area for librarian involvement. This column highlights opportunities and challenges for the librarian working on guideline panels and provides practical considerations for meaningful contributions to the guideline creation process.

  11. AACSB Standards and Accounting Faculty's Intellectual Contributions

    Science.gov (United States)

    Lee, B. Brian; Quddus, Munir

    2008-01-01

    The authors performed a content analysis of intellectual contribution portfolios of accounting faculty at various business schools that Association to Advance Collegiate Schools of Business International recently accredited. The results showed a significant divergence in faculty research (e.g., areas, topics) and their teaching assignments. This…

  12. The economic contribution of tourism in Mozambique

    DEFF Research Database (Denmark)

    Jones, Edward Samuel

    2010-01-01

    of various tourism sub-types. Multiplier analysis is applied to evaluate the strength of backward linkages from tourism to the domestic economy. The results show the sector is moderate in size but has the potential to contribute significantly to aggregate economic development. However, potential weaknesses...... are already evident and careful attention must be paid to the full tourism value chain....

  13. Interaction between Tropical Atlantic Variability and El Niño-Southern Oscillation.

    Science.gov (United States)

    Saravanan, R.; Chang, Ping

    2000-07-01

    The interaction between tropical Atlantic variability and El Niño-Southern Oscillation (ENSO) is investigated using three ensembles of atmospheric general circulation model integrations. The integrations are forced by specifying observed sea surface temperature (SST) variability over a forcing domain. The forcing domain is the global ocean for the first ensemble, limited to the tropical ocean for the second ensemble, and further limited to the tropical Atlantic region for the third ensemble. The ensemble integrations show that extratropical SST anomalies have little impact on tropical variability, but the effect of ENSO is pervasive in the Tropics. Consistent with previous studies, the most significant influence of ENSO is found during the boreal spring season and is associated with an anomalous Walker circulation. Two important aspects of ENSO's influence on tropical Atlantic variability are noted. First, the ENSO signal contributes significantly to the `dipole' correlation structure between tropical Atlantic SST and rainfall in the Nordeste Brazil region. In the absence of the ENSO signal, the correlations are dominated by SST variability in the southern tropical Atlantic, resulting in less of a dipole structure. Second, the remote influence of ENSO also contributes to positive correlations between SST anomalies and downward surface heat flux in the tropical Atlantic during the boreal spring season. However, even when ENSO forcing is absent, the model integrations provide evidence for a positive surface heat flux feedback in the deep Tropics, which is analyzed in a companion study by Chang et al. The analysis of model simulations shows that interannual atmospheric variability in the tropical Pacific-Atlantic system is dominated by the interaction between two distinct sources of tropical heating: (i) an equatorial heat source in the eastern Pacific associated with ENSO and (ii) an off-equatorial heat source associated with SST anomalies near the Caribbean

  14. Optical variability of the Seyfert galaxy nuclei

    International Nuclear Information System (INIS)

    Lyutyj, V.M.

    1979-01-01

    The results of the UBV observations of compact Seyfert galaxies during 1968-78 are given. The full amplitude ΔB approximately 2sup(m) of the variability of the nucleus of 3C 120 is considerably larger than that of any other Seyfert galaxy. The minimum brightness of 3C 120 in 1978, B=16sup(m).25 was observed for the first time during the photometric history of the object since 1900. The time delay Δt < or approximately 70sup(d) of the variability of colour index U-B of the nucleus of 3C 120 relatively to that of B and B-V have been discovered. This time delay is interpreted as the variability of the Balmer continuum. The nucleus of 2 Zw 136 appears to show such a variability also. The location of 3C 120 and 2 Zw 136 on two-colour diagram corresponds to the combined colours of hot (05) and cold (K-M) stars, if the time delay of U-B variability is taken into account. The colour indices of the nucleus of 3C 120 during the minimum of 1978 (B=16sup(m).25) correspond to those of the ring between the 7''-30'' apertures. This indicates to a very small contributions of the variable source during the 1978 minimum

  15. An examination of the variables influencing the fuel retail industry

    Directory of Open Access Journals (Sweden)

    K. Sartorius

    2007-12-01

    Full Text Available Purpose/objectives: The objective of the study is to contribute to a better understanding of the key variables that influence the profitability of this sector, as well as to develop a reliable model to predict retail fuel sales volumes in an urban setting. Problem investigated: South African fuel retail outlets are confronted by a wide range of variables that constrain profit and a significant number of outlets are not profitable. In the event of further deregulation, it is conceivable that many fuel stations will go out of business. Methodology: A combination of a quantitative and a case study methodology, in conjunction with a literature review, was used to test the principal research questions. Findings/implications: The results suggest that location significantly influences urban retail fuel sales volumes whilst fuel station size and the fuel price play a lesser role. Other significant factors, however, also influence fuel station profitability. The demand for petrol appears to be relatively inelastic in the short term and more elastic over the long term. Conversely, the demand for diesel appears to be completely inelastic. Value: The article promotes a better understanding of the cost dynamics of the fuel industry. In this regard, the model constructed to predict urban fuel station turnover indicated high levels of reliability. Furthermore, few comparable studies have been published in accounting journals. Conclusion: The study concludes that urban petrol stations selling more than 370 000 liters of fuel per month are likely to be profitable and that location is a key variable influencing sales. In the event of deregulation, many operators are likely to be eliminated because of high levels of competition and low profit margins. An even greater number of fuel stations, therefore, will be reliant on non forecourt activities to survive.

  16. Corporate campaign contributions and abnormal stock returns after presidential elections

    OpenAIRE

    Juergen Huber; Michael Kirchler

    2008-01-01

    In the U.S. campaign contributions by companies play a major role in financing election campaigns. We analyze contributions by companies before an election and stock market performance after the election for the presidential elections from 1992 until 2004. We find that (i) the percentage of contributions given to the winner in a presidential election and (ii) the total contribution (divided by market capitalization) have a significant positive impact on a company's stock market performance af...

  17. Variable screening and ranking using sampling-based sensitivity measures

    International Nuclear Information System (INIS)

    Wu, Y-T.; Mohanty, Sitakanta

    2006-01-01

    This paper presents a methodology for screening insignificant random variables and ranking significant important random variables using sensitivity measures including two cumulative distribution function (CDF)-based and two mean-response based measures. The methodology features (1) using random samples to compute sensitivities and (2) using acceptance limits, derived from the test-of-hypothesis, to classify significant and insignificant random variables. Because no approximation is needed in either the form of the performance functions or the type of continuous distribution functions representing input variables, the sampling-based approach can handle highly nonlinear functions with non-normal variables. The main characteristics and effectiveness of the sampling-based sensitivity measures are investigated using both simple and complex examples. Because the number of samples needed does not depend on the number of variables, the methodology appears to be particularly suitable for problems with large, complex models that have large numbers of random variables but relatively few numbers of significant random variables

  18. THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: RAPID C iv BROAD ABSORPTION LINE VARIABILITY

    International Nuclear Information System (INIS)

    Grier, C. J.; Brandt, W. N.; Trump, J. R.; Schneider, D. P.; Hall, P. B.; Shen, Yue; Vivek, M.; Dawson, K. S.; Ak, N. Filiz; Chen, Yuguang; Denney, K. D.; Kochanek, C. S.; Peterson, B. M.; Green, Paul J.; Jiang, Linhua; McGreer, Ian D.; Pâris, I.; Tao, Charling; Wood-Vasey, W. M.; Bizyaev, Dmitry

    2015-01-01

    We report the discovery of rapid variations of a high-velocity C iv broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4σ) variability in the equivalent width (EW) of the broad (∼4000 km s −1 wide) C iv trough on rest-frame timescales as short as 1.20 days (∼29 hr), the shortest broad absorption line variability timescale yet reported. The EW varied by ∼10% on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n e ≳ 3.9 × 10 5 cm −3 . The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios

  19. Choice between variable and fixed cocaine injections in male rhesus monkeys.

    Science.gov (United States)

    Huskinson, S L; Freeman, K B; Petry, N M; Rowlett, J K

    2017-08-01

    The schedule of drug availability may enhance choice of a drug. In non-human subjects, reinforcers are chosen more often when available under variable schedules of reinforcement relative to fixed schedules. To determine whether variable-drug access is an important determinant of cocaine choice by manipulating the schedule, drug dose, and combination of schedule + dose. Four male rhesus monkeys chose between cocaine doses (0.025-0.4 mg/kg/injection). In control conditions, the schedule and dose of each drug delivery were fixed. In other conditions, the reinforcement schedule (i.e., variable-ratio schedule), dose of each cocaine delivery, or both were variable on one lever while all aspects on the other lever remained fixed. When cocaine dose was equal on average (0.1 mg/kg/injection), 2 of 4 subjects chose cocaine associated with the variable schedule more than the fixed schedule. All subjects chose the variable dose that was equal on average to the fixed dose, and this difference was statistically significant. Three of 4 subjects chose cocaine associated with the variable combination over the fixed option (when the dose was equal on average). During dose-response determinations (when dose on the variable and fixed options were not equal), making the schedule, dose, or both variable generally did not alter cocaine's potency as a reinforcer. While many factors contribute to drug choice, unpredictable drug access is a feature that may be common in the natural environment and could play a key role in the allocation of behavior to drug alternatives by patients with substance-use disorders.

  20. Rackspace: Significance of Cloud Computing to CERN

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    The research collaboration between Rackspace and CERN is contributing to how OpenStack cloud computing will move science work around the world for CERN, and to reducing the barriers between clouds for Rackspace.

  1. Gene variants associated with antisocial behaviour: a latent variable approach.

    Science.gov (United States)

    Bentley, Mary Jane; Lin, Haiqun; Fernandez, Thomas V; Lee, Maria; Yrigollen, Carolyn M; Pakstis, Andrew J; Katsovich, Liliya; Olds, David L; Grigorenko, Elena L; Leckman, James F

    2013-10-01

    The aim of this study was to determine if a latent variable approach might be useful in identifying shared variance across genetic risk alleles that is associated with antisocial behaviour at age 15 years. Using a conventional latent variable approach, we derived an antisocial phenotype in 328 adolescents utilizing data from a 15-year follow-up of a randomized trial of a prenatal and infancy nurse-home visitation programme in Elmira, New York. We then investigated, via a novel latent variable approach, 450 informative genetic polymorphisms in 71 genes previously associated with antisocial behaviour, drug use, affiliative behaviours and stress response in 241 consenting individuals for whom DNA was available. Haplotype and Pathway analyses were also performed. Eight single-nucleotide polymorphisms (SNPs) from eight genes contributed to the latent genetic variable that in turn accounted for 16.0% of the variance within the latent antisocial phenotype. The number of risk alleles was linearly related to the latent antisocial variable scores. Haplotypes that included the putative risk alleles for all eight genes were also associated with higher latent antisocial variable scores. In addition, 33 SNPs from 63 of the remaining genes were also significant when added to the final model. Many of these genes interact on a molecular level, forming molecular networks. The results support a role for genes related to dopamine, norepinephrine, serotonin, glutamate, opioid and cholinergic signalling as well as stress response pathways in mediating susceptibility to antisocial behaviour. This preliminary study supports use of relevant behavioural indicators and latent variable approaches to study the potential 'co-action' of gene variants associated with antisocial behaviour. It also underscores the cumulative relevance of common genetic variants for understanding the aetiology of complex behaviour. If replicated in future studies, this approach may allow the identification of a

  2. Spatial variability of sediment transport processes over intra‐ and subtidal timescales within a fringing coral reef system

    Science.gov (United States)

    Pomeroy, Andrew; Lowe, Ryan J.; Ghisalberti, Marco; Winter, Gundula; Storlazzi, Curt D.; Cuttler, Michael V. W.

    2018-01-01

    Sediment produced on fringing coral reefs that is transported along the bed or in suspension affects ecological reef communities as well as the morphological development of the reef, lagoon, and adjacent shoreline. This study quantified the physical process contribution and relative importance of incident waves, infragravity waves, and mean currents to the spatial and temporal variability of sediment in suspension. Estimates of bed shear stresses demonstrate that incident waves are the key driver of the SSC variability spatially (reef flat, lagoon, and channels) but cannot not fully describe the SSC variability alone. The comparatively small but statistically significant contribution to the bed shear stress by infragravity waves and currents, along with the spatial availability of sediment of a suitable size and volume, is also important. Although intra‐tidal variability in SSC occurs in the different reef zones, the majority of the variability occurs over longer slowly varying (subtidal) time scales, which is related to the arrival of large incident waves at a reef location. The predominant flow pathway, which can transport suspended sediment, consists of cross‐reef flow across the reef flat that diverges in the lagoon and returns offshore through channels. This pathway is primarily due to subtidal variations in wave‐driven flows, but can also be driven alongshore by wind stresses when the incident waves are small. Higher frequency (intra‐tidal) current variability also occur due to both tidal flows, as well as variations in the water depth that influence wave transmission across the reef and wave‐driven currents.

  3. Contribution of "Women's Gold" to West African livelihoods

    DEFF Research Database (Denmark)

    Pouliot, Mariéve

    2012-01-01

    Contribution of ``Women's Gold'' to West African Livelihoods: The Case of Shea ( Vitellaria paradoxa ) in Burkina Faso. This paper (i) quantifies the contribution that Vitellaria paradoxa makes to the total income of rural households belonging to different economic groups in two areas of Burkina ...... not be considered as a remedy to poverty but instead as a way for households to diversify their livelihood strategy and decrease their vulnerability to food insecurity and climate variability....

  4. Variable Permanent Magnet Quadrupole

    International Nuclear Information System (INIS)

    Mihara, T.; Iwashita, Y.; Kyoto U.; Kumada, M.; NIRS, Chiba; Spencer, C.M.; SLAC

    2007-01-01

    A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments

  5. On Complex Random Variables

    Directory of Open Access Journals (Sweden)

    Anwer Khurshid

    2012-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE In this paper, it is shown that a complex multivariate random variable  is a complex multivariate normal random variable of dimensionality if and only if all nondegenerate complex linear combinations of  have a complex univariate normal distribution. The characteristic function of  has been derived, and simpler forms of some theorems have been given using this characterization theorem without assuming that the variance-covariance matrix of the vector  is Hermitian positive definite. Marginal distributions of  have been given. In addition, a complex multivariate t-distribution has been defined and the density derived. A characterization of the complex multivariate t-distribution is given. A few possible uses of this distribution have been suggested.

  6. What nuclear power can contribute

    International Nuclear Information System (INIS)

    Schwarz, D.

    1997-01-01

    The big tasks of mankind are: Development, protection of the environment, peace, and saving of resources on behalf of coming generations. Poverty exerts the greatest stress upon nature, development and protection of the environment are therefore not contradictory. Mankind has enough energy and mineral resources (sources), enough technology to limit detrimental effluents (taking care of sinks), and enough capital to bring about well-being for all mankind. Well-being decelerates population growth; in this way a stable coexistence of man and nature can be achieved. To this goal, nuclear energy can contribute significantly. Even at a considerably higher level of exploitation, it would last for several 100 000 years. Nuclear energy can supply every kind of energy required and, jointly with higher efficiency, it can do so at low cost; as to that, nuclear energy is superior to renewable energies in most cases. Also, nuclear energy can be deployed quickly enough. At the present safety level (including fuel cycle) the risks of deploying nuclear energy are smaller than the risks of non-deployment, by several orders of magnitude, both with respect to risk magnitude and probability. The material basis for a sustainable well-being of man and nature on this earth does exist. To-day's prime issue is to remove mental road blocks. (orig.) [de

  7. 75 FR 34388 - Employee Contribution Elections and Contribution Allocations

    Science.gov (United States)

    2010-06-17

    ... contributions equal to 3 percent of the employee's basic pay will be deducted from his or her pay and... employees who are rehired after a separation in service of 31 or more calendar days and who are eligible to participate in the TSP will automatically have 3 percent of their basic pay contributed to the TSP, unless...

  8. Hidden variables and locality in quantum theory

    International Nuclear Information System (INIS)

    Shiva, Vandana.

    1978-12-01

    The status of hidden variables in quantum theory has been debated since the 1920s. The author examines the no-hidden-variable theories of von Neumann, Kochen, Specker and Bell, and finds that they all share one basic assumption: averaging over the hidden variables should reproduce the quantum mechanical probabilities. Von Neumann also makes a linearity assumption, Kochen and Specker require the preservation of certain functional relations between magnitudes, and Bell proposes a locality condition. It has been assumed that the extrastatistical requirements are needed to serve as criteria of success for the introduction of hidden variables because the statistical condition is trivially satisfied, and that Bell's result is based on a locality condition that is physically motivated. The author shows that the requirement of weak locality, which is not physically motivated, is enough to give Bell's result. The proof of Bell's inequality works equally well for any pair of commuting magnitudes satisfying a condition called the degeneracy principle. None of the no-hidden-variable proofs apply to a class of hidden variable theories that are not phase-space reconstructions of quantum mechanics. The author discusses one of these theories, the Bohm-Bub theory, and finds that hidden variable theories that re all the quantum statistics, for single and sequential measurements, must introduce a randomization process for the hidden variables after each measurement. The philosophical significance of this theory lies in the role it can play in solving the conceptual puzzles posed by quantum theory

  9. Variable Kernel Density Estimation

    OpenAIRE

    Terrell, George R.; Scott, David W.

    1992-01-01

    We investigate some of the possibilities for improvement of univariate and multivariate kernel density estimates by varying the window over the domain of estimation, pointwise and globally. Two general approaches are to vary the window width by the point of estimation and by point of the sample observation. The first possibility is shown to be of little efficacy in one variable. In particular, nearest-neighbor estimators in all versions perform poorly in one and two dimensions, but begin to b...

  10. TEC variability over Havana

    International Nuclear Information System (INIS)

    Lazo, B.; Alazo, K.; Rodriguez, M.; Calzadilla, A.

    2003-01-01

    The variability of total electron content (TEC) measured over Havana using ATS-6, SMS-1 and GOES-3 geosynchronous satellite signals has been investigated for low, middle and high solar activity periods from 1974 to 1982. The obtained results show that standard deviation is smooth during nighttime hours and maximum at noon or postnoon hours. Strong solar activity dependence of standard deviation with a maximum values during HSA has been found. (author)

  11. Short timescale variability in the faint sky variability survey

    NARCIS (Netherlands)

    Morales-Rueda, L.; Groot, P.J.; Augusteijn, T.; Nelemans, G.A.; Vreeswijk, P.M.; Besselaar, E.J.M. van den

    2006-01-01

    We present the V-band variability analysis of the Faint Sky Variability Survey (FSVS). The FSVS combines colour and time variability information, from timescales of 24 minutes to tens of days, down to V = 24. We find that �1% of all point sources are variable along the main sequence reaching �3.5%

  12. Prognostic Significance of Signet Ring Gastric Cancer

    Science.gov (United States)

    Taghavi, Sharven; Jayarajan, Senthil N.; Davey, Adam; Willis, Alliric I.

    2012-01-01

    Purpose Studies in Asia have questioned the dictum that signet ring cell carcinoma (SRC) has a worse prognosis than other forms of gastric cancer. Our study determined differences in presentation and outcomes between SRC and gastric adenocarcinoma (AC) in the United States. Patients and Methods The National Cancer Institute Surveillance, Epidemiology, and End Results database was reviewed for SRC and AC from 2004 to 2007. Results We reviewed 10,246 cases of patients with gastric cancer, including 2,666 of SRC and 7,580 of AC. SRC presented in younger patients (61.9 v 68.7 years; P < .001) and less often in men (52.7% v 68.7%; P < .001). SRC patients were more frequently black (11.3% v 10.9%), Asian (16.4% v 13.2%), American Indian/Alaska Native (0.9% v 0.8%), or Hispanic (23.3% v 14.0%; P < .001). SRC was more likely to be stage T3-4 (45.8% v 33.3%), have lymph node spread (59.7% v 51.8%), and distant metastases (40.2% v 37.6%; P < .001). SRC was more likely to be found in the lower (30.7% v 24.2%) and middle stomach (30.6% v 20.7%; P < .001). Median survival was not different between the two (AC, 14.0 months v SRC, 13.0 months; P = .073). Multivariable analyses demonstrated SRC was not associated with mortality (hazard ratio [HR], 1.05; 95% CI, 0.96 to 1.11; P = .150). Mortality was associated with age (HR, 1.01; 95% CI, 1.01 to 1.02; P < .001), black race (HR, 1.10; 95% CI, 1.01 to 1.20; P = .026), and tumor grade. Variables associated with lower mortality risk included Asian race (HR, 0.83; 95% CI, 0.77 to 0.91; P < .001) and surgery (HR, 0.37; 95% CI, 0.34 to 0.39; P < .001). Conclusion In the United States, SRC significantly differs from AC in extent of disease at presentation. However, when adjusted for stage, SRC does not portend a worse prognosis. PMID:22927530

  13. Contribution of attachment insecurity to health-related quality of life in depressed patients.

    Science.gov (United States)

    Ponizovsky, Alexander M; Drannikov, Angela

    2013-06-22

    To examine the individual contributions of insecure attachment styles and depression symptom severity to health-related quality of life (HRQoL) in patients diagnosed with adjustment disorder (AJD) with depressed mood. Participants were 67 patients diagnosed with International Classification of Diseases, Tenth edition AJD with depressed mood, who completed standardised self-report questionnaires measuring study variables. Mean scores and SDs were computed for the outcome and predictor measures. Pearson correlations among the measures were computed. The study hypotheses were tested using analysis of variance (ANOVA) and multiple regression analyses. All analyses were performed using the SPSS-17 software package (SPSS Inc., Chicago, IL, United States). ANOVA showed a significant main effect of the insecure attachment styles on depression symptom severity and life satisfaction scores. The results suggest that depressive symptoms were more severe (F = 4.13, df = 2.67, P insecure groups did not significantly differ by these variables. The anxious/ambivalent attachment style and depression symptom severity significantly contributed to HRQoL, accounting for 21.4% and 29.7% of the total variance, respectively [R(2) = 0.79; Adjusted R(2) = 0.77; F (5, 67) = 33.68, P < 0.0001], even after controlling for gender, marital and employment status confounders. The results show that the anxious/ambivalent attachment style together with depression symptom severity substantially and independently predict the HRQoL outcome in AJD with depressed mood.

  14. Port Contribution to the Calapan City Development in the Province of Oriental Mindoro, Philippines

    Directory of Open Access Journals (Sweden)

    Christian Anthony C. Agutaya

    2016-11-01

    Full Text Available The study assessed the extent of port contribution to the Calapan City development in the province of Oriental Mindoro, Philippines. It used descriptive research designed and involved 20 arrastre and PPA personnel, 5 ship managers, 10 truckers and 15 passengers who were purposively selected, came from Calapan City, represented significant contribution specifically using the port and could give knowledgeable information on port activities. It also utilized open-ended questionnaire and unstructured interviews. The study found out that Calapan City Port contributed to the development of the city in terms of agriculture and trade and industry to a very high extent. However, Calapan Port only contributed to the development of Calapan City in terms of tourism, education, health finance and power/energy and telecommunication only to a high extent. An accounted data on inbound and outbound of products, commodities and people who make use of the port for socio-economic functions should be presented with due concern to the city government of Calapan so that a combined effort for further improvements of key areas should be undertaken jointly by Philippines Port Authority and the city's concerned agencies. A further and deeper study with due consideration of other Philippines Port Authority (PPA - managed ports in Oriental Mindoro which cover various variables as contributions of local government units to port development, needed services by port users and PPA's organizational climate and culture should be undertaken by future researchers.

  15. Purposeful selection of variables in logistic regression

    Directory of Open Access Journals (Sweden)

    Williams David Keith

    2008-12-01

    Full Text Available Abstract Background The main problem in many model-building situations is to choose from a large set of covariates those that should be included in the "best" model. A decision to keep a variable in the model might be based on the clinical or statistical significance. There are several variable selection algorithms in existence. Those methods are mechanical and as such carry some limitations. Hosmer and Lemeshow describe a purposeful selection of covariates within which an analyst makes a variable selection decision at each step of the modeling process. Methods In this paper we introduce an algorithm which automates that process. We conduct a simulation study to compare the performance of this algorithm with three well documented variable selection procedures in SAS PROC LOGISTIC: FORWARD, BACKWARD, and STEPWISE. Results We show that the advantage of this approach is when the analyst is interested in risk factor modeling and not just prediction. In addition to significant covariates, this variable selection procedure has the capability of retaining important confounding variables, resulting potentially in a slightly richer model. Application of the macro is further illustrated with the Hosmer and Lemeshow Worchester Heart Attack Study (WHAS data. Conclusion If an analyst is in need of an algorithm that will help guide the retention of significant covariates as well as confounding ones they should consider this macro as an alternative tool.

  16. Environmental radioactivity: A perspective on industrial contributions

    International Nuclear Information System (INIS)

    Baxter, M.S.

    1993-01-01

    This essay aims to show how many non-nuclear industries contributed significantly to natural radioactivity. The examples given include the release of radon-220 and radon-222, as well as other radioisotopes, from the combustion of fossil fuels. Furthermore, edible mussels in the Irish Sea have been found to concentrate polonium-210 from seawater: the original source of the isotope was found to be the waste from a phosphate processing plant. These contributions should be taken into account when the environmental impacts of different industrial activities are compared. 3 tabs

  17. Environmental radioactivity: A perspective on industrial contributions

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, M S [International Atomic Energy Agency, Monaco (Monaco). Marine Environment Lab.

    1993-06-01

    This essay aims to show how many non-nuclear industries contributed significantly to natural radioactivity. The examples given include the release of radon-220 and radon-222, as well as other radioisotopes, from the combustion of fossil fuels. Furthermore, edible mussels in the Irish Sea have been found to concentrate polonium-210 from seawater: the original source of the isotope was found to be the waste from a phosphate processing plant. These contributions should be taken into account when the environmental impacts of different industrial activities are compared. 3 tabs.

  18. Meta-analysis of variables affecting mouse protection efficacy of whole organism Brucella vaccines and vaccine candidates

    Science.gov (United States)

    2013-01-01

    Background Vaccine protection investigation includes three processes: vaccination, pathogen challenge, and vaccine protection efficacy assessment. Many variables can affect the results of vaccine protection. Brucella, a genus of facultative intracellular bacteria, is the etiologic agent of brucellosis in humans and multiple animal species. Extensive research has been conducted in developing effective live attenuated Brucella vaccines. We hypothesized that some variables play a more important role than others in determining vaccine protective efficacy. Using Brucella vaccines and vaccine candidates as study models, this hypothesis was tested by meta-analysis of Brucella vaccine studies reported in the literature. Results Nineteen variables related to vaccine-induced protection of mice against infection with virulent brucellae were selected based on modeling investigation of the vaccine protection processes. The variable "vaccine protection efficacy" was set as a dependent variable while the other eighteen were set as independent variables. Discrete or continuous values were collected from papers for each variable of each data set. In total, 401 experimental groups were manually annotated from 74 peer-reviewed publications containing mouse protection data for live attenuated Brucella vaccines or vaccine candidates. Our ANOVA analysis indicated that nine variables contributed significantly (P-value Brucella vaccine protection efficacy: vaccine strain, vaccination host (mouse) strain, vaccination dose, vaccination route, challenge pathogen strain, challenge route, challenge-killing interval, colony forming units (CFUs) in mouse spleen, and CFU reduction compared to control group. The other 10 variables (e.g., mouse age, vaccination-challenge interval, and challenge dose) were not found to be statistically significant (P-value > 0.05). The protection level of RB51 was sacrificed when the values of several variables (e.g., vaccination route, vaccine viability, and

  19. About hidden influence of predictor variables: Suppressor and mediator variables

    Directory of Open Access Journals (Sweden)

    Milovanović Boško

    2013-01-01

    Full Text Available In this paper procedure for researching hidden influence of predictor variables in regression models and depicting suppressor variables and mediator variables is shown. It is also shown that detection of suppressor variables and mediator variables could provide refined information about the research problem. As an example for applying this procedure, relation between Atlantic atmospheric centers and air temperature and precipitation amount in Serbia is chosen. [Projekat Ministarstva nauke Republike Srbije, br. 47007

  20. Contribution of WHOQOL-Bref in the quality of life of workers in a radioactive installation

    International Nuclear Information System (INIS)

    Fernandes, Ivani M.; Silva, Amanda J. da; Potiens, Maria da Penha A.; Carneiro, Janete C.G.G.

    2011-01-01

    This paper analysed the contribution of WHOQOL-Bref (physical, social, psychological and environmental) for the global life quality of individual occupationally exposed to ionizing radiations and to verify its interrelationship with the social demographic variables, its work conditions and life style. The studied sample (n=86) has answered to a questionnaire composed by socio demographic, work conditions and life style questions and by the WHOQOL-Bref instrument. The data analysis involved descriptive and non parametric tests. The results shown that the psychological domain obtained more average score (75.9+-12.4) and the environmental less score (62.5+-11.4). It was observed significant correlations (p<0.05) among the four domains of the WHOQOL-Bref and the studied variables. The internal consistency of the instrument, evaluated by Alpha of Cronbach, for the studied sample was considered high (0.832)

  1. Clinical Implications of Glucose Variability: Chronic Complications of Diabetes

    Directory of Open Access Journals (Sweden)

    Hye Seung Jung

    2015-06-01

    Full Text Available Glucose variability has been identified as a potential risk factor for diabetic complications; oxidative stress is widely regarded as the mechanism by which glycemic variability induces diabetic complications. However, there remains no generally accepted gold standard for assessing glucose variability. Representative indices for measuring intraday variability include calculation of the standard deviation along with the mean amplitude of glycemic excursions (MAGE. MAGE is used to measure major intraday excursions and is easily measured using continuous glucose monitoring systems. Despite a lack of randomized controlled trials, recent clinical data suggest that long-term glycemic variability, as determined by variability in hemoglobin A1c, may contribute to the development of microvascular complications. Intraday glycemic variability is also suggested to accelerate coronary artery disease in high-risk patients.

  2. Hydrological and environmental variables outperform spatial factors in structuring species, trait composition, and beta diversity of pelagic algae.

    Science.gov (United States)

    Wu, Naicheng; Qu, Yueming; Guse, Björn; Makarevičiūtė, Kristė; To, Szewing; Riis, Tenna; Fohrer, Nicola

    2018-03-01

    There has been increasing interest in algae-based bioassessment, particularly, trait-based approaches are increasingly suggested. However, the main drivers, especially the contribution of hydrological variables, of species composition, trait composition, and beta diversity of algae communities are less studied. To link species and trait composition to multiple factors (i.e., hydrological variables, local environmental variables, and spatial factors) that potentially control species occurrence/abundance and to determine their relative roles in shaping species composition, trait composition, and beta diversities of pelagic algae communities, samples were collected from a German lowland catchment, where a well-proven ecohydrological modeling enabled to predict long-term discharges at each sampling site. Both trait and species composition showed significant correlations with hydrological, environmental, and spatial variables, and variation partitioning revealed that the hydrological and local environmental variables outperformed spatial variables. A higher variation of trait composition (57.0%) than species composition (37.5%) could be explained by abiotic factors. Mantel tests showed that both species and trait-based beta diversities were mostly related to hydrological and environmental heterogeneity with hydrological contributing more than environmental variables, while purely spatial impact was less important. Our findings revealed the relative importance of hydrological variables in shaping pelagic algae community and their spatial patterns of beta diversities, emphasizing the need to include hydrological variables in long-term biomonitoring campaigns and biodiversity conservation or restoration. A key implication for biodiversity conservation was that maintaining the instream flow regime and keeping various habitats among rivers are of vital importance. However, further investigations at multispatial and temporal scales are greatly needed.

  3. How may the basal ganglia contribute to auditory categorization and speech perception?

    Directory of Open Access Journals (Sweden)

    Sung-Joo eLim

    2014-08-01

    Full Text Available Listeners must accomplish two complementary perceptual feats in extracting a message from speech. They must discriminate linguistically-relevant acoustic variability and generalize across irrelevant variability. Said another way, they must categorize speech. Since the mapping of acoustic variability is language-specific, these categories must be learned from experience. Thus, understanding how, in general, the auditory system acquires and represents categories can inform us about the toolbox of mechanisms available to speech perception. This perspective invites consideration of findings from cognitive neuroscience literatures outside of the speech domain as a means of constraining models of speech perception. Although neurobiological models of speech perception have mainly focused on cerebral cortex, research outside the speech domain is consistent with the possibility of significant subcortical contributions in category learning. Here, we review the functional role of one such structure, the basal ganglia. We examine research from animal electrophysiology, human neuroimaging, and behavior to consider characteristics of basal ganglia processing that may be advantageous for speech category learning. We also present emerging evidence for a direct role for basal ganglia in learning auditory categories in a complex, naturalistic task intended to model the incidental manner in which speech categories are acquired. To conclude, we highlight new research questions that arise in incorporating the broader neuroscience research literature in modeling speech perception, and suggest how understanding contributions of the basal ganglia can inform attempts to optimize training protocols for learning non-native speech categories in adulthood.

  4. Motor skills in kindergarten: Internal structure, cognitive correlates and relationships to background variables.

    Science.gov (United States)

    Oberer, Nicole; Gashaj, Venera; Roebers, Claudia M

    2017-04-01

    The present study aimed to contribute to the discussion about the relation between motor coordination and executive functions in preschool children. Specifically, the relation between gross and fine motor skills and executive functions as well as the relation to possible background variables (SES, physical activity) were investigated. Based on the data of N=156 kindergarten children the internal structure of motor skills was investigated and confirmed the theoretically assumed subdivision of gross and fine motor skills. Both, gross and fine motor skills correlated significantly with executive functions, whereas the background variables seemed to have no significant impact on the executive functions and motor skills. Higher order control processes are discussed as an explanation of the relation between executive functions and motor skills. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The significance of deaf identity for psychological well-being

    DEFF Research Database (Denmark)

    Chapman, Madeleine; Dammeyer, Jesper

    2017-01-01

    of psychological well-being than those with a marginal identity. Further, it found that additional disability, educational level, and feeling discriminated against significantly and independently explained the degree of psychological well-being. Results are discussed here with respect to social identity theory......Research has paid attention to how deaf identity affects life outcomes such as psychological well-being. However, studies are often carried out with small samples and without controlling for other variables. This study examined how different forms of identity—deaf, hearing, bicultural (deaf...... and hearing), and marginal (neither deaf nor hearing)—were associated with levels of psychological well-being and a number of other variables. The sample was 742 adults with hearing loss in Denmark. The study found that those with a deaf, hearing or bicultural identity had significantly higher levels...

  6. The Significance of Loyalty on Consumer Credit Profitability

    Directory of Open Access Journals (Sweden)

    Aditya Galih Prihartono

    2012-04-01

    Full Text Available The purpose of this research is to analyze and test the effect of customer loyalty on consumer credit profitability. Loyalty Index Score was developed to determine the level of customers’ loyalty level through 4 main variables; Longevity, Depth, Breadth and Referrals. The effect of Loyalty Index Score on profitability was further tested by path analysis to find out the significance direct relationship between loyalty and profitablity and the indirect relationship between the two variable through bucket. The result showed that loyalty has a significant effect on profitability either directly or indirectly. It was concluded that direct loyalty effect on profitability is lower than that of the indirect effect through bucket. The conclusion could be made by analyzing the available data from personal loan customers in one of the biggest multinational bank in indonesia during October 2010 until March 2011.

  7. COP 21: the national contributions

    International Nuclear Information System (INIS)

    Jouette, Isabelle

    2015-01-01

    This article comments the content of the national contributions (the so-called Intended Nationally Determined Contributions or INDC) which every country should have transmitted to the UN before the COP 21. In fact, 148 contributions, i.e. 75 per cent of the expected ones, have been transmitted. The author recalls that the content of these contributions had to obey some principles which had been defined in Lima in 2014, and that each country must identify its objectives in terms of mitigation (reduction of greenhouse gas emissions) and adaptation (reduction of the vulnerability of natural and human systems). The author comments some specific commitments regarding climate, emission reduction, adaptation to climate change, and more particularly evokes the Ethiopian contribution which is considered as exemplary

  8. Working memory contributions to reading comprehension components in middle childhood children.

    Science.gov (United States)

    Chrysochoou, Elisavet; Bablekou, Zoe; Tsigilis, Nikolaos

    2011-01-01

    This study examined working memory contributions to reading comprehension subskills in Greek children (mean age 9 years, 1 month). The phonological loop of the Baddeley and Hitch working memory model was assessed with 3 recall tasks (words, nonwords, and digits) and a word list matching task. The central executive (CE) was assessed with 3 tasks (listening, counting, and backward digit recall). Participants were also given a receptive vocabulary task, a reading fluency task, and written stories accompanied by comprehension questions. Canonical correlation analyses showed that the comprehension variables were related to the CE rather than the phonological loop measures. CE functions were more strongly associated with elaborative inference generation (involving significant offline processing) and comprehension control (involving metacognitive monitoring). Smaller yet significant associations were observed between the CE and the necessary inference and literal comprehension measures, whereas a moderate relationship was found in the case of the simile comprehension variable. Among the CE variables, listening recall demonstrated the highest loading on the canonical function, followed by moderate yet significant counting and backward digit recall loadings. Vocabulary was found to fully mediate several associations between working memory and comprehension measures; however, the relationship between listening recall and elaborative inferences was partly mediated. Reading fluency and, on several occasions, Greek vocabulary knowledge did not mediate the relationships between CE measures and comprehension skills assessed. This study demonstrates the usefulness of CE measures for identifying young children's possible difficulties in carrying out specific reading comprehension processes.

  9. Greenhouse effect contributions of US landfill methane

    International Nuclear Information System (INIS)

    Augenstein, D.

    1991-01-01

    The greenhouse effect has recently been receiving a great deal of scientific and popular attention. The term refers to a cause-and-effect relationship in which ''heat blanketing'' of the earth, due to trace gas increases in the atmosphere, is expected to result in global warming. The trace gases are increasing as the result of human activities. Carbon dioxide (CO 2 ) is the trace gas contributing most importantly to the ''heat blanketing'' and currently receives the most attention. Less widely recognized has been the high importance of methane (CH 4 ). Methane's contribution to the increased heat blanketing occurring since 1980 is estimated to be over a third as much as that of carbon dioxide. Gas from landfills has in turn been recognized to be a source of methane to the atmospheric buildup. However the magnitude of the landfill methane contribution, and the overall significance of landfill methane to the greenhouse phenomenon has been uncertain and the subject of some debate. (Author)

  10. Factors contributing to outcome following traumatic brain injury.

    Science.gov (United States)

    Ponsford, Jennie

    2013-01-01

    Traumatic brain injury results in some distinctive patterns of cognitive, behavioural and physical impairment which impact significantly on independent living skills and participation in work or study, social and leisure activities and interpersonal relationships. There is, however, still considerable variability in outcome across individuals in each of the reported domains. This has led to a significant body of research examining factors associated with outcome. A range of injury-related, personal and social factors have been shown to influence survival, as well as cognitive, functional and employment outcome. This paper reviews the factors associated with each of these aspects of outcome specifically injury-related factors, including neuroimaging findings, GCS and PTA, other injuries, and cognitive and behavioural impairments; demographic factors, including age, gender, genetic status, education, pre-injury IQ and employment status; and social factors including family and other social support, cultural factors, pre-injury psychiatric history and coping style. The paper identifies contributions and complex interrelationships of all of these factors to outcome following TBI. It concludes with a brief discussion of the implications of these factors for the rehabilitation process.

  11. Variability in Antibiotic Use Across PICUs.

    Science.gov (United States)

    Brogan, Thomas V; Thurm, Cary; Hersh, Adam L; Gerber, Jeffrey S; Smith, Michael J; Shah, Samir S; Courter, Joshua D; Patel, Sameer J; Parker, Sarah K; Kronman, Matthew P; Lee, Brian R; Newland, Jason G

    2018-03-10

    To characterize and compare antibiotic prescribing across PICUs to evaluate the degree of variability. Retrospective analysis from 2010 through 2014 of the Pediatric Health Information System. Forty-one freestanding children's hospital. Children aged 30 days to 18 years admitted to a PICU in children's hospitals contributing data to Pediatric Health Information System. To normalize for potential differences in disease severity and case mix across centers, a subanalysis was performed of children admitted with one of the 20 All Patient Refined-Diagnosis Related Groups and the seven All Patient Refined-Diagnosis Related Groups shared by all PICUs with the highest antibiotic use. The study included 3,101,201 hospital discharges from 41 institutions with 386,914 PICU patients. All antibiotic use declined during the study period. The median-adjusted antibiotic use among PICU patients was 1,043 days of therapy/1,000 patient-days (interquartile range, 977-1,147 days of therapy/1,000 patient-days) compared with 893 among non-ICU children (interquartile range, 805-968 days of therapy/1,000 patient-days). For PICU patients, the median adjusted use of broad-spectrum antibiotics was 176 days of therapy/1,000 patient-days (interquartile range, 152-217 days of therapy/1,000 patient-days) and was 302 days of therapy/1,000 patient-days (interquartile range, 220-351 days of therapy/1,000 patient-days) for antimethicillin-resistant Staphylococcus aureus agents, compared with 153 days of therapy/1,000 patient-days (interquartile range, 130-182 days of therapy/1,000 patient-days) and 244 days of therapy/1,000 patient-days (interquartile range, 203-270 days of therapy/1,000 patient-days) for non-ICU children. After adjusting for potential confounders, significant institutional variability existed in antibiotic use in PICU patients, in the 20 All Patient Refined-Diagnosis Related Groups with the highest antibiotic usage and in the seven All Patient Refined-Diagnosis Related Groups shared

  12. Tracking variable sedimentation rates in orbitally forced paleoclimate proxy series

    Science.gov (United States)

    Li, M.; Kump, L. R.; Hinnov, L.

    2017-12-01

    This study addresses two fundamental issues in cyclostratigraphy: quantitative testing of orbital forcing in cyclic sedimentary sequences and tracking variable sedimentation rates. The methodology proposed here addresses these issues as an inverse problem, and estimates the product-moment correlation coefficient between the frequency spectra of orbital solutions and paleoclimate proxy series over a range of "test" sedimentation rates. It is inspired by the ASM method (1). The number of orbital parameters involved in the estimation is also considered. The method relies on the hypothesis that orbital forcing had a significant impact on the paleoclimate proxy variations, and thus is also tested. The null hypothesis of no astronomical forcing is evaluated using the Beta distribution, for which the shape parameters are estimated using a Monte Carlo simulation approach. We introduce a metric to estimate the most likely sedimentation rate using the product-moment correlation coefficient, H0 significance level, and the number of contributing orbital parameters, i.e., the CHO value. The CHO metric is applied with a sliding window to track variable sedimentation rates along the paleoclimate proxy series. Two forward models with uniform and variable sedimentation rates are evaluated to demonstrate the robustness of the method. The CHO method is applied to the classical Late Triassic Newark depth rank series; the estimated sedimentation rates match closely with previously published sedimentation rates and provide a more highly time-resolved estimate (2,3). References: (1) Meyers, S.R., Sageman, B.B., Amer. J. Sci., 307, 773-792, 2007; (2) Kent, D.V., Olsen, P.E., Muttoni, G., Earth-Sci. Rev.166, 153-180, 2017; (3) Li, M., Zhang, Y., Huang, C., Ogg, J., Hinnov, L., Wang, Y., Zou, Z., Li, L., 2017. Earth Plant. Sc. Lett. doi:10.1016/j.epsl.2017.07.015

  13. Radiocaesium variability in upland sheep flocks

    Energy Technology Data Exchange (ETDEWEB)

    Beresford, N.A

    2002-07-01

    Following the 1986 Chernobyl accident large areas of uplands in the United Kingdom were contaminated by radiocaesium. Consequently, the level of radiocaesium in the tissues of some sheep exceeded 1000 Bq kg{sup -1} fresh weight This is the limit adopted within the UK above which meat cannot enter the food chain. In 1986, restrictions were placed on the movement and slaughter of sheep in areas of west Cumbria, north Wales and Scotland. Whilst the number of farms under restriction has reduced considerably, some still remain restricted in 2002. Although a number of workers had noted considerable variability between the radiocaesium activities of individuals within sheep flocks there had been no analyses of causal effects. The work described here, combined studies on three upland farms within west Cumbria with controlled feeding experiments, to systematically assess the parameters which may contribute to such variability. Results from all three farms demonstrate a temporally consistent ranking of the {sup 137}Cs activity concentration of individual sheep within the study flocks. As there was also a correlation between the {sup 137}Cs activity concentration of ewes and their pre-weaned lambs it is likely that the same ewes are producing lambs in excess of the intervention limit in subsequent years. It is difficult to generalise as to which factors will contribute to {sup 137}Cs variability within a given upland flock; factors contributing to variation were not consistent between the study farms. However, the location grazed and/or vegetation selected by animals was a causal factor to the observed variability at all three farms. The transfer of radiocaesium from the diet to muscle of sheep was found to be determined by live-weight change and dry matter intake. Subsequent studies have suggested that protein turnover may be a potential mechanism for the relationship between dry matter intake and radiocaesium transfer. This hypothesis is supported by current understanding

  14. Radiocaesium variability in upland sheep flocks

    International Nuclear Information System (INIS)

    Beresford, N.A.

    2002-01-01

    Following the 1986 Chernobyl accident large areas of uplands in the United Kingdom were contaminated by radiocaesium. Consequently, the level of radiocaesium in the tissues of some sheep exceeded 1000 Bq kg -1 fresh weight This is the limit adopted within the UK above which meat cannot enter the food chain. In 1986, restrictions were placed on the movement and slaughter of sheep in areas of west Cumbria, north Wales and Scotland. Whilst the number of farms under restriction has reduced considerably, some still remain restricted in 2002. Although a number of workers had noted considerable variability between the radiocaesium activities of individuals within sheep flocks there had been no analyses of causal effects. The work described here, combined studies on three upland farms within west Cumbria with controlled feeding experiments, to systematically assess the parameters which may contribute to such variability. Results from all three farms demonstrate a temporally consistent ranking of the 137 Cs activity concentration of individual sheep within the study flocks. As there was also a correlation between the 137 Cs activity concentration of ewes and their pre-weaned lambs it is likely that the same ewes are producing lambs in excess of the intervention limit in subsequent years. It is difficult to generalise as to which factors will contribute to 137 Cs variability within a given upland flock; factors contributing to variation were not consistent between the study farms. However, the location grazed and/or vegetation selected by animals was a causal factor to the observed variability at all three farms. The transfer of radiocaesium from the diet to muscle of sheep was found to be determined by live-weight change and dry matter intake. Subsequent studies have suggested that protein turnover may be a potential mechanism for the relationship between dry matter intake and radiocaesium transfer. This hypothesis is supported by current understanding of protein-dry matter

  15. Predicting Students' Skills in the Context of Scientific Inquiry with Cognitive, Motivational, and Sociodemographic Variables

    Science.gov (United States)

    Nehring, Andreas; Nowak, Kathrin H.; Belzen, Annette Upmeier zu; Tiemann, Rüdiger

    2015-06-01

    Research on predictors of achievement in science is often targeted on more traditional content-based assessments and single student characteristics. At the same time, the development of skills in the field of scientific inquiry constitutes a focal point of interest for science education. Against this background, the purpose of this study was to investigate to which extent multiple student characteristics contribute to skills of scientific inquiry. Based on a theoretical framework describing nine epistemological acts, we constructed and administered a multiple-choice test that assesses these skills in lower and upper secondary school level (n = 780). The test items contained problem-solving situations that occur during chemical investigations in school and had to be solved by choosing an appropriate inquiry procedure. We collected further data on 12 cognitive, motivational, and sociodemographic variables such as conceptual knowledge, enjoyment of chemistry, or language spoken at home. Plausible values were drawn to quantify students' inquiry skills. The results show that students' characteristics predict their inquiry skills to a large extent (55%), whereas 9 out of 12 variables contribute significantly on a multivariate level. The influence of sociodemographic traits such as gender or the social background becomes non-significant after controlling for cognitive and motivational variables. Furthermore, the performance advance of students from upper secondary school level can be explained by controlling for cognitive covariates. We discuss our findings with regard to curricular aspects and raise the question whether the inquiry skills can be considered as an autonomous trait in science education research.

  16. High beat-to-beat blood pressure variability in atrial fibrillation compared to sinus rhythm.

    Science.gov (United States)

    Olbers, Joakim; Gille, Adam; Ljungman, Petter; Rosenqvist, Mårten; Östergren, Jan; Witt, Nils

    2018-02-07

    Atrial fibrillation (AF) is associated with an increased risk for cardiovascular morbidity and mortality, not entirely explained by thromboembolism. The underlying mechanisms for this association are largely unknown. Similarly, high blood pressure (BP) increases the risk for cardiovascular events. Despite this the interplay between AF and BP is insufficiently studied. The purpose of this study was to examine and quantify the beat-to-beat blood pressure variability in patients with AF in comparison to a control group of patients with sinus rhythm. We studied 33 patients - 21 in atrial fibrillation and 12 in sinus rhythm - undergoing routine coronary angiography. Invasive blood pressure was recorded at three locations: radial artery, brachial artery and ascending aorta. Blood pressure variability, defined as average beat-to-beat blood pressure difference, was calculated for systolic and diastolic blood pressure at each site. We observed a significant difference (p blood pressure variability between the atrial fibrillation and sinus rhythm groups at all locations. Systolic blood pressure variability roughly doubled in the atrial fibrillation group compared to the sinus rhythm group (4.9 and 2.4 mmHg respectively). Diastolic beat-to-beat blood pressure variability was approximately 6 times as high in the atrial fibrillation group compared to the sinus rhythm group (7.5 and 1.2 mmHg respectively). No significant difference in blood pressure variability was seen between measurement locations. Beat-to-beat blood pressure variability in patients with atrial fibrillation was substantially higher than in patients with sinus rhythm. Hemodynamic effects of this beat-to-beat variation in blood pressure may negatively affect vascular structure and function, which may contribute to the increased cardiovascular morbidity and mortality seen in patients with atrial fibrillation.

  17. Individual Variability in Aerobic Fitness Adaptations to 70-d of Bed Rest and Exercise Training

    Science.gov (United States)

    Downs, Meghan; Buxton, Roxanne; Goetchius, Elizabeth; DeWitt, John; Ploutz-Snyder, Lori

    2016-01-01

    Change in maximal aerobic capacity (VO2pk) in response to exercise training and disuse is highly variable among individuals. Factors that could contribute to the observed variability (lean mass, daily activity, diet, sleep, stress) are not routinely controlled in studies. The NASA bed rest (BR) studies use a highly controlled hospital based model as an analog of spaceflight. In this study, diet, hydration, physical activity and light/dark cycles were precisely controlled and provided the opportunity to investigate individual variability. PURPOSE. Evaluate the contribution of exercise intensity and lean mass on change in VO2pk during 70-d of BR or BR + exercise. METHODS. Subjects completed 70-d of BR alone (CON, N=9) or BR + exercise (EX, N=17). The exercise prescription included 6 d/wk of aerobic exercise at 70 - 100% of max and 3 d/wk of lower body resistance exercise. Subjects were monitored 24 hr/d. VO2pk and lean mass (iDXA) were measured pre and post BR. ANOVA was used to evaluate changes in VO2pk pre to post BR. Subjects were retrospectively divided into high and low responders based on change in VO2pk (CON > 20% loss, n=5; EX >10% loss, n=4, or 5% gain, n=4) to further understand individual variability. RESULTS. VO2pk decreased from pre to post BR in CON (Pexercise intensity. CONCLUSION. Change in VO2pk in response to disuse and exercise was highly variable among individuals, even in this tightly controlled study. Loss in lean mass accounts for a significant degree of variability in the CON; however, training induced gains in VO2pk appear unrelated to lean mass or exercise intensity.

  18. Factors contributing to home delivery in Kongwa District, Dodoma ...

    African Journals Online (AJOL)

    Objectives: To determine factors contributing to home delivery in Kongwa District. Methods: A community-based cross-sectional study was conducted in September 2009 in which women of child-bearing age were interviewed. The variables mainly included: accessibility of maternal health care, practicing TBA's, existence of ...

  19. Contribution of timber exports to economic growth in Nigeria: an ...

    African Journals Online (AJOL)

    The paper examined the contribution of timber exports to the economic growth in Nigeria, using an econometric approach. Augmented Dickey-Fuller (ADF) and Johansen Co-integration techniques were respectively used to test for unit root and examine the relationship between the variables used. In addition, Granger ...

  20. Heart rate variability in healthy population

    International Nuclear Information System (INIS)

    Alamgir, M.; Hussain, M.M.

    2010-01-01

    Background: Heart rate variability has been considered as an indicator of autonomic status. Little work has been done on heart rate variability in normal healthy volunteers. We aimed at evolving the reference values of heart rate variability in our healthy population. Methods: Twenty-four hour holter monitoring of 37 healthy individuals was done using Holter ECG recorder 'Life card CF' from 'Reynolds Medical'. Heart rate variability in both time and frequency domains was analysed with 'Reynolds Medical Pathfinder Digital/700'. Results: The heart rate variability in normal healthy volunteers of our population was found in time domain using standard deviation of R-R intervals (SDNN), standard deviation of average NN intervals (SDANN), and Square root of the mean squared differences of successive NN intervals (RMSSD). Variation in heart rate variability indices was observed between local and foreign volunteers and RMSSD was found significantly increased (p<0.05) in local population. Conclusions: The values of heart rate variability (RMSSD) in healthy Pakistani volunteers were found increased compared to the foreign data reflecting parasympathetic dominance in our population. (author)