Challenging terrestrial biosphere models with data from the long-term multifactor Prairie Heating and CO 2 enrichment experiment

DOE PAGES

De Kauwe, Martin G.; Medlyn, Belinda E.; Walker, Anthony P.; ...

2017-02-01

Multi-factor experiments are often advocated as important for advancing terrestrial biosphere models (TBMs), yet to date such models have only been tested against single-factor experiments. We applied 10 TBMs to the multi-factor Prairie Heating and CO 2 Enrichment (PHACE) experiment in Wyoming, USA. Our goals were to investigate how multi-factor experiments can be used to constrain models, and to identify a road map for model improvement. We found models performed poorly in ambient conditions; there was a wide spread in simulated above-ground net primary productivity (range: 31-390 g C m -2 yr -1). Comparison with data highlighted model failures particularlymore » in respect to carbon allocation, phenology, and the impact of water stress on phenology. Performance against single-factors was also relatively poor. In addition, similar responses were predicted for different reasons across models: there were large differences among models in sensitivity to water stress and, among the nitrogen cycle models, nitrogen availability during the experiment. Models were also unable to capture observed treatment effects on phenology: they over-estimated the effect of warming on leaf onset and did not allow CO 2-induced water savings to extend growing season length. Observed interactive (CO 2 x warming) treatment effects were subtle and contingent on water stress, phenology and species composition. Since the models did not correctly represent these processes under ambient and single-factor conditions, little extra information was gained by comparing model predictions against interactive responses. Finally, we outline a series of key areas in which this and future experiments could be used to improve model predictions of grassland responses to global change.« less

Teacher Perceptions of Principals' Leadership Qualities: A Mixed Methods Study

ERIC Educational Resources Information Center

Hauserman, Cal P.; Ivankova, Nataliya V.; Stick, Sheldon L.

2013-01-01

This mixed methods sequential explanatory study utilized the Multi-factor Leadership Questionnaire, responses to open-ended questions, and in-depth interviews to identify transformational leadership qualities that were present among principals in Alberta, Canada. The first quantitative phase consisted of a random sample of 135 schools (with…

A Comparative Study on Multifactor Dimensionality Reduction Methods for Detecting Gene-Gene Interactions with the Survival Phenotype

PubMed Central

Lee, Seungyeoun; Kim, Yongkang; Kwon, Min-Seok; Park, Taesung

2015-01-01

Genome-wide association studies (GWAS) have extensively analyzed single SNP effects on a wide variety of common and complex diseases and found many genetic variants associated with diseases. However, there is still a large portion of the genetic variants left unexplained. This missing heritability problem might be due to the analytical strategy that limits analyses to only single SNPs. One of possible approaches to the missing heritability problem is to consider identifying multi-SNP effects or gene-gene interactions. The multifactor dimensionality reduction method has been widely used to detect gene-gene interactions based on the constructive induction by classifying high-dimensional genotype combinations into one-dimensional variable with two attributes of high risk and low risk for the case-control study. Many modifications of MDR have been proposed and also extended to the survival phenotype. In this study, we propose several extensions of MDR for the survival phenotype and compare the proposed extensions with earlier MDR through comprehensive simulation studies. PMID:26339630

Simulation of probabilistic wind loads and building analysis

NASA Technical Reports Server (NTRS)

Shah, Ashwin R.; Chamis, Christos C.

1991-01-01

Probabilistic wind loads likely to occur on a structure during its design life are predicted. Described here is a suitable multifactor interactive equation (MFIE) model and its use in the Composite Load Spectra (CLS) computer program to simulate the wind pressure cumulative distribution functions on four sides of a building. The simulated probabilistic wind pressure load was applied to a building frame, and cumulative distribution functions of sway displacements and reliability against overturning were obtained using NESSUS (Numerical Evaluation of Stochastic Structure Under Stress), a stochastic finite element computer code. The geometry of the building and the properties of building members were also considered as random in the NESSUS analysis. The uncertainties of wind pressure, building geometry, and member section property were qualified in terms of their respective sensitivities on the structural response.

Fatigue failure of materials under broad band random vibrations

NASA Technical Reports Server (NTRS)

Huang, T. C.; Lanz, R. W.

1971-01-01

The fatigue life of material under multifactor influence of broad band random excitations has been investigated. Parameters which affect the fatigue life are postulated to be peak stress, variance of stress and the natural frequency of the system. Experimental data were processed by the hybrid computer. Based on the experimental results and regression analysis a best predicting model has been found. All values of the experimental fatigue lives are within the 95% confidence intervals of the predicting equation.

A detailed view on Model-Based Multifactor Dimensionality Reduction for detecting gene-gene interactions in case-control data in the absence and presence of noise

PubMed Central

CATTAERT, TOM; CALLE, M. LUZ; DUDEK, SCOTT M.; MAHACHIE JOHN, JESTINAH M.; VAN LISHOUT, FRANÇOIS; URREA, VICTOR; RITCHIE, MARYLYN D.; VAN STEEN, KRISTEL

2010-01-01

SUMMARY Analyzing the combined effects of genes and/or environmental factors on the development of complex diseases is a great challenge from both the statistical and computational perspective, even using a relatively small number of genetic and non-genetic exposures. Several data mining methods have been proposed for interaction analysis, among them, the Multifactor Dimensionality Reduction Method (MDR), which has proven its utility in a variety of theoretical and practical settings. Model-Based Multifactor Dimensionality Reduction (MB-MDR), a relatively new MDR-based technique that is able to unify the best of both non-parametric and parametric worlds, was developed to address some of the remaining concerns that go along with an MDR-analysis. These include the restriction to univariate, dichotomous traits, the absence of flexible ways to adjust for lower-order effects and important confounders, and the difficulty to highlight epistasis effects when too many multi-locus genotype cells are pooled into two new genotype groups. Whereas the true value of MB-MDR can only reveal itself by extensive applications of the method in a variety of real-life scenarios, here we investigate the empirical power of MB-MDR to detect gene-gene interactions in the absence of any noise and in the presence of genotyping error, missing data, phenocopy, and genetic heterogeneity. For the considered simulation settings, we show that the power is generally higher for MB-MDR than for MDR, in particular in the presence of genetic heterogeneity, phenocopy, or low minor allele frequencies. PMID:21158747

A survey about methods dedicated to epistasis detection.

PubMed

Niel, Clément; Sinoquet, Christine; Dina, Christian; Rocheleau, Ghislain

2015-01-01

During the past decade, findings of genome-wide association studies (GWAS) improved our knowledge and understanding of disease genetics. To date, thousands of SNPs have been associated with diseases and other complex traits. Statistical analysis typically looks for association between a phenotype and a SNP taken individually via single-locus tests. However, geneticists admit this is an oversimplified approach to tackle the complexity of underlying biological mechanisms. Interaction between SNPs, namely epistasis, must be considered. Unfortunately, epistasis detection gives rise to analytic challenges since analyzing every SNP combination is at present impractical at a genome-wide scale. In this review, we will present the main strategies recently proposed to detect epistatic interactions, along with their operating principle. Some of these methods are exhaustive, such as multifactor dimensionality reduction, likelihood ratio-based tests or receiver operating characteristic curve analysis; some are non-exhaustive, such as machine learning techniques (random forests, Bayesian networks) or combinatorial optimization approaches (ant colony optimization, computational evolution system).

Interactions between MAOA and SYP polymorphisms were associated with symptoms of attention-deficit/hyperactivity disorder in Chinese Han subjects.

PubMed

Gao, Qian; Liu, Lu; Li, Hai-Mei; Tang, Yi-Lang; Wu, Zhao-Min; Chen, Yun; Wang, Yu-Feng; Qian, Qiu-Jin

2015-01-01

As candidate genes of attention--deficit/hyperactivity disorder (ADHD), monoamine oxidase A (MAOA), and synaptophysin (SYP) are both on the X chromosome, and have been suggested to be associated with the predominantly inattentive subtype (ADHD-I). The present study is to investigate the potential gene-gene interaction (G × G) between rs5905859 of MAOA and rs5906754 of SYP for ADHD in Chinese Han subjects. For family-based association study, 177 female trios were included. For case-control study, 1,462 probands and 807 normal controls were recruited. The ADHD Rating Scale-IV (ADHD-RS-IV) was used to evaluate ADHD symptoms. Pedigree-based generalized multifactor dimensionality reduction (PGMDR) for female ADHD trios indicated significant gene interaction effect of rs5905859 and rs5906754. Generalized multifactor dimensionality reduction (GMDR) indicated potential gene-gene interplay on ADHD RS-IV scores in female ADHD-I. No associations were observed in male subjects in case-control analysis. In conclusion, our findings suggested that the interaction of MAOA and SYP may be involved in the genetic mechanism of ADHD-I subtype and predict ADHD symptoms. © 2014 Wiley Periodicals, Inc.

Prediction of passenger ride quality in a multifactor environment

NASA Technical Reports Server (NTRS)

Dempsey, T. K.; Leatherwood, J. D.

1976-01-01

A model being developed, permits the understanding and prediction of passenger discomfort in a multifactor environment with particular emphasis upon combined noise and vibration. The model has general applicability to diverse transportation systems and provides a means of developing ride quality design criteria as well as a diagnostic tool for identifying the vibration and/or noise stimuli causing discomfort. Presented are: (1) a review of the basic theoretical and mathematical computations associated with the model, (2) a discussion of methodological and criteria investigations for both the vertical and roll axes of vibration, (3) a description of within-axis masking of discomfort responses for the vertical axis, thereby allowing prediction of the total discomfort due to any random vertical vibration, (4) a discussion of initial data on between-axis masking, and (5) discussion of a study directed towards extension of the vibration model to the more general case of predicting ride quality in the combined noise and vibration environments.

Estimation and analysis of multifactor productivity in truck transportation : 1987 - 2003

DOT National Transportation Integrated Search

2009-02-01

The analysis has three objectives: 1) to estimate multifactor : productivity (MFP) in truck transportation during : 1987-2003; 2) to examine changes in multifactor productivity : in U.S. truck transportation, over time, and : to compare these changes...

Multifactor-Dimensionality Reduction Reveals High-Order Interactions among Estrogen-Metabolism Genes in Sporadic Breast Cancer

PubMed Central

Ritchie, Marylyn D.; Hahn, Lance W.; Roodi, Nady; Bailey, L. Renee; Dupont, William D.; Parl, Fritz F.; Moore, Jason H.

2001-01-01

One of the greatest challenges facing human geneticists is the identification and characterization of susceptibility genes for common complex multifactorial human diseases. This challenge is partly due to the limitations of parametric-statistical methods for detection of gene effects that are dependent solely or partially on interactions with other genes and with environmental exposures. We introduce multifactor-dimensionality reduction (MDR) as a method for reducing the dimensionality of multilocus information, to improve the identification of polymorphism combinations associated with disease risk. The MDR method is nonparametric (i.e., no hypothesis about the value of a statistical parameter is made), is model-free (i.e., it assumes no particular inheritance model), and is directly applicable to case-control and discordant-sib-pair studies. Using simulated case-control data, we demonstrate that MDR has reasonable power to identify interactions among two or more loci in relatively small samples. When it was applied to a sporadic breast cancer case-control data set, in the absence of any statistically significant independent main effects, MDR identified a statistically significant high-order interaction among four polymorphisms from three different estrogen-metabolism genes. To our knowledge, this is the first report of a four-locus interaction associated with a common complex multifactorial disease. PMID:11404819

A Simple and Computationally Efficient Sampling Approach to Covariate Adjustment for Multifactor Dimensionality Reduction Analysis of Epistasis

PubMed Central

Gui, Jiang; Andrew, Angeline S.; Andrews, Peter; Nelson, Heather M.; Kelsey, Karl T.; Karagas, Margaret R.; Moore, Jason H.

2010-01-01

Epistasis or gene-gene interaction is a fundamental component of the genetic architecture of complex traits such as disease susceptibility. Multifactor dimensionality reduction (MDR) was developed as a nonparametric and model-free method to detect epistasis when there are no significant marginal genetic effects. However, in many studies of complex disease, other covariates like age of onset and smoking status could have a strong main effect and may potentially interfere with MDR's ability to achieve its goal. In this paper, we present a simple and computationally efficient sampling method to adjust for covariate effects in MDR. We use simulation to show that after adjustment, MDR has sufficient power to detect true gene-gene interactions. We also compare our method with the state-of-art technique in covariate adjustment. The results suggest that our proposed method performs similarly, but is more computationally efficient. We then apply this new method to an analysis of a population-based bladder cancer study in New Hampshire. PMID:20924193

Probabilistic Multi-Factor Interaction Model for Complex Material Behavior

NASA Technical Reports Server (NTRS)

Abumeri, Galib H.; Chamis, Christos C.

2010-01-01

Complex material behavior is represented by a single equation of product form to account for interaction among the various factors. The factors are selected by the physics of the problem and the environment that the model is to represent. For example, different factors will be required for each to represent temperature, moisture, erosion, corrosion, etc. It is important that the equation represent the physics of the behavior in its entirety accurately. The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the external launch tanks. The multi-factor has sufficient degrees of freedom to evaluate a large number of factors that may contribute to the divot ejection. It also accommodates all interactions by its product form. Each factor has an exponent that satisfies only two points - the initial and final points. The exponent describes a monotonic path from the initial condition to the final. The exponent values are selected so that the described path makes sense in the absence of experimental data. In the present investigation, the data used were obtained by testing simulated specimens in launching conditions. Results show that the MFIM is an effective method of describing the divot weight ejected under the conditions investigated. The problem lies in how to represent the divot weight with a single equation. A unique solution to this problem is a multi-factor equation of product form. Each factor is of the following form (1 xi/xf)ei, where xi is the initial value, usually at ambient conditions, xf the final value, and ei the exponent that makes the curve represented unimodal that meets the initial and final values. The exponents are either evaluated by test data or by technical judgment. A minor disadvantage may be the selection of exponents in the absence of any empirical data. This form has been used successfully in describing the foam ejected in simulated space environmental conditions. Seven factors were required to represent the ejected foam. The exponents were evaluated by least squares method from experimental data. The equation is used and it can represent multiple factors in other problems as well; for example, evaluation of fatigue life, creep life, fracture toughness, and structural fracture, as well as optimization functions. The software is rather simplistic. Required inputs are initial value, final value, and an exponent for each factor. The number of factors is open-ended. The value is updated as each factor is evaluated. If a factor goes to zero, the previous value is used in the evaluation.

Multi-factor challenge/response approach for remote biometric authentication

NASA Astrophysics Data System (ADS)

Al-Assam, Hisham; Jassim, Sabah A.

2011-06-01

Although biometric authentication is perceived to be more reliable than traditional authentication schemes, it becomes vulnerable to many attacks when it comes to remote authentication over open networks and raises serious privacy concerns. This paper proposes a biometric-based challenge-response approach to be used for remote authentication between two parties A and B over open networks. In the proposed approach, a remote authenticator system B (e.g. a bank) challenges its client A who wants to authenticate his/her self to the system by sending a one-time public random challenge. The client A responds by employing the random challenge along with secret information obtained from a password and a token to produce a one-time cancellable representation of his freshly captured biometric sample. The one-time biometric representation, which is based on multi-factor, is then sent back to B for matching. Here, we argue that eavesdropping of the one-time random challenge and/or the resulting one-time biometric representation does not compromise the security of the system, and no information about the original biometric data is leaked. In addition to securing biometric templates, the proposed protocol offers a practical solution for the replay attack on biometric systems. Moreover, we propose a new scheme for generating a password-based pseudo random numbers/permutation to be used as a building block in the proposed approach. The proposed scheme is also designed to provide protection against repudiation. We illustrate the viability and effectiveness of the proposed approach by experimental results based on two biometric modalities: fingerprint and face biometrics.

A Guide to the Multifactored Evaluation (MFE).

ERIC Educational Resources Information Center

Ohio Coalition for the Education of Children with Disabilities, Marion.

This guide provides Ohio parents of children with disabilities with information on multifactored evaluations. It begins by discussing the Intervention Assistance Team and what occurs at the assistance team meeting. It also explains that to begin the multifactored evaluation process, the parent must complete a "Request for Parent Consent for…

Research on accuracy analysis of laser transmission system based on Zemax and Matlab

NASA Astrophysics Data System (ADS)

Chen, Haiping; Liu, Changchun; Ye, Haixian; Xiong, Zhao; Cao, Tingfen

2017-05-01

Laser transmission system is important in high power solid-state laser facilities and its function is to transfer and focus the light beam in accordance with the physical function of the facility. This system is mainly composed of transmission mirror modules and wedge lens module. In order to realize the precision alignment of the system, the precision alignment of the system is required to be decomposed into the allowable range of the calibration error of each module. The traditional method is to analyze the error factors of the modules separately, and then the linear synthesis is carried out, and the influence of the multi-module and multi-factor is obtained. In order to analyze the effect of the alignment error of each module on the beam center and focus more accurately, this paper aims to combine with the Monte Carlo random test and ray tracing, analyze influence of multi-module and multi-factor on the center of the beam, and evaluate and optimize the results of accuracy decomposition.

Multi-factor authentication using quantum communication

DOEpatents

Hughes, Richard John; Peterson, Charles Glen; Thrasher, James T.; Nordholt, Jane E.; Yard, Jon T.; Newell, Raymond Thorson; Somma, Rolando D.

2018-02-06

Multi-factor authentication using quantum communication ("QC") includes stages for enrollment and identification. For example, a user enrolls for multi-factor authentication that uses QC with a trusted authority. The trusted authority transmits device factor information associated with a user device (such as a hash function) and user factor information associated with the user (such as an encrypted version of a user password). The user device receives and stores the device factor information and user factor information. For multi-factor authentication that uses QC, the user device retrieves its stored device factor information and user factor information, then transmits the user factor information to the trusted authority, which also retrieves its stored device factor information. The user device and trusted authority use the device factor information and user factor information (more specifically, information such as a user password that is the basis of the user factor information) in multi-factor authentication that uses QC.

Prioritization of candidate disease genes by combining topological similarity and semantic similarity.

PubMed

Liu, Bin; Jin, Min; Zeng, Pan

2015-10-01

The identification of gene-phenotype relationships is very important for the treatment of human diseases. Studies have shown that genes causing the same or similar phenotypes tend to interact with each other in a protein-protein interaction (PPI) network. Thus, many identification methods based on the PPI network model have achieved good results. However, in the PPI network, some interactions between the proteins encoded by candidate gene and the proteins encoded by known disease genes are very weak. Therefore, some studies have combined the PPI network with other genomic information and reported good predictive performances. However, we believe that the results could be further improved. In this paper, we propose a new method that uses the semantic similarity between the candidate gene and known disease genes to set the initial probability vector of a random walk with a restart algorithm in a human PPI network. The effectiveness of our method was demonstrated by leave-one-out cross-validation, and the experimental results indicated that our method outperformed other methods. Additionally, our method can predict new causative genes of multifactor diseases, including Parkinson's disease, breast cancer and obesity. The top predictions were good and consistent with the findings in the literature, which further illustrates the effectiveness of our method. Copyright © 2015 Elsevier Inc. All rights reserved.

Exploring the interaction among EPHX1, GSTP1, SERPINE2, and TGFB1 contributing to the quantitative traits of chronic obstructive pulmonary disease in Chinese Han population.

PubMed

An, Li; Lin, Yingxiang; Yang, Ting; Hua, Lin

2016-05-18

Currently, the majority of genetic association studies on chronic obstructive pulmonary disease (COPD) risk focused on identifying the individual effects of single nucleotide polymorphisms (SNPs) as well as their interaction effects on the disease. However, conventional genetic studies often use binary disease status as the primary phenotype, but for COPD, many quantitative traits have the potential correlation with the disease status and closely reflect pathological changes. Here, we genotyped 44 SNPs from four genes (EPHX1, GSTP1, SERPINE2, and TGFB1) in 310 patients and 203 controls which belonged to the Chinese Han population to test the two-way and three-way genetic interactions with COPD-related quantitative traits using recently developed generalized multifactor dimensionality reduction (GMDR) and quantitative multifactor dimensionality reduction (QMDR) algorithms. Based on the 310 patients and the whole samples of 513 subjects, the best gene-gene interactions models were detected for four lung-function-related quantitative traits. For the forced expiratory volume in 1 s (FEV1), the best interaction was seen from EPHX1, SERPINE2, and GSTP1. For FEV1%pre, the forced vital capacity (FVC), and FEV1/FVC, the best interactions were seen from SERPINE2 and TGFB1. The results of this study provide further evidence for the genotype combinations at risk of developing COPD in Chinese Han population and improve the understanding on the genetic etiology of COPD and COPD-related quantitative traits.

Technical Note: Introduction of variance component analysis to setup error analysis in radiotherapy

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

Matsuo, Yukinori, E-mail: ymatsuo@kuhp.kyoto-u.ac.

Purpose: The purpose of this technical note is to introduce variance component analysis to the estimation of systematic and random components in setup error of radiotherapy. Methods: Balanced data according to the one-factor random effect model were assumed. Results: Analysis-of-variance (ANOVA)-based computation was applied to estimate the values and their confidence intervals (CIs) for systematic and random errors and the population mean of setup errors. The conventional method overestimates systematic error, especially in hypofractionated settings. The CI for systematic error becomes much wider than that for random error. The ANOVA-based estimation can be extended to a multifactor model considering multiplemore » causes of setup errors (e.g., interpatient, interfraction, and intrafraction). Conclusions: Variance component analysis may lead to novel applications to setup error analysis in radiotherapy.« less

Probabilistic sizing of laminates with uncertainties

NASA Technical Reports Server (NTRS)

Shah, A. R.; Liaw, D. G.; Chamis, C. C.

1993-01-01

A reliability based design methodology for laminate sizing and configuration for a special case of composite structures is described. The methodology combines probabilistic composite mechanics with probabilistic structural analysis. The uncertainties of constituent materials (fiber and matrix) to predict macroscopic behavior are simulated using probabilistic theory. Uncertainties in the degradation of composite material properties are included in this design methodology. A multi-factor interaction equation is used to evaluate load and environment dependent degradation of the composite material properties at the micromechanics level. The methodology is integrated into a computer code IPACS (Integrated Probabilistic Assessment of Composite Structures). Versatility of this design approach is demonstrated by performing a multi-level probabilistic analysis to size the laminates for design structural reliability of random type structures. The results show that laminate configurations can be selected to improve the structural reliability from three failures in 1000, to no failures in one million. Results also show that the laminates with the highest reliability are the least sensitive to the loading conditions.

Interrelationships of metal transfer factor under wastewater reuse and soil pollution.

PubMed

Papaioannou, D; Kalavrouziotis, I K; Koukoulakis, P H; Papadopoulos, F; Psoma, P

2018-06-15

The transfer of heavy metals under soil pollution wastewater reuse was studied in a Greenhouse experiment using a randomized block design, including 6 treatments of heavy metals mixtures composed of Zn, Mn, Cd, Co, Cu, Cr, Ni, and Pb, where each metal was taking part in the mixture with 0, 10, 20, 30, 40, 50 mg/kg respectively, in four replications. The Beta vulgaris L (beet) was used as a test plant. It was found that the metal transfer factors were statistically significantly related to the: (i) DTPA extractable soil metals, (ii) the soil pollution level as assessed by the pollution indices, (iii) the soil pH, (iv) the beet dry matter yield and (v) the interactions between the heavy metals in the soil. It was concluded that the Transfer Factor is subjected to multifactor effects and its real nature is complex, and there is a strong need for further study for the understanding of its role in metal-plant relationships. Copyright © 2017 Elsevier Ltd. All rights reserved.

Power of data mining methods to detect genetic associations and interactions.

PubMed

Molinaro, Annette M; Carriero, Nicholas; Bjornson, Robert; Hartge, Patricia; Rothman, Nathaniel; Chatterjee, Nilanjan

2011-01-01

Genetic association studies, thus far, have focused on the analysis of individual main effects of SNP markers. Nonetheless, there is a clear need for modeling epistasis or gene-gene interactions to better understand the biologic basis of existing associations. Tree-based methods have been widely studied as tools for building prediction models based on complex variable interactions. An understanding of the power of such methods for the discovery of genetic associations in the presence of complex interactions is of great importance. Here, we systematically evaluate the power of three leading algorithms: random forests (RF), Monte Carlo logic regression (MCLR), and multifactor dimensionality reduction (MDR). We use the algorithm-specific variable importance measures (VIMs) as statistics and employ permutation-based resampling to generate the null distribution and associated p values. The power of the three is assessed via simulation studies. Additionally, in a data analysis, we evaluate the associations between individual SNPs in pro-inflammatory and immunoregulatory genes and the risk of non-Hodgkin lymphoma. The power of RF is highest in all simulation models, that of MCLR is similar to RF in half, and that of MDR is consistently the lowest. Our study indicates that the power of RF VIMs is most reliable. However, in addition to tuning parameters, the power of RF is notably influenced by the type of variable (continuous vs. categorical) and the chosen VIM. Copyright © 2011 S. Karger AG, Basel.

Effect of five enological practices and of the general phenolic composition on fermentation-related aroma compounds in Mencia young red wines.

PubMed

Añón, Ana; López, Jorge F; Hernando, Diego; Orriols, Ignacio; Revilla, Eugenio; Losada, Manuel M

2014-04-01

The effects of five technological procedures and of the contents of total anthocyanins and condensed tannins on 19 fermentation-related aroma compounds of young red Mencia wines were studied. Multifactor ANOVA revealed that levels of those volatiles changed significantly over the length of storage in bottles and, to a lesser extent, due to other technological factors considered; total anthocyanins and condensed tannins also changed significantly as a result of the five practices assayed. Five aroma compounds possessed an odour activity value >1 in all wines, and another four in some wines. Linear correlation among volatile compounds and general phenolic composition revealed that total anthocyanins were highly related to 14 different aroma compounds. Multifactor ANOVA, considering the content of total anthocyanins as a sixth random factor, revealed that this parameter affected significantly the contents of ethyl lactate, ethyl isovalerate, 1-pentanol and ethyl octanoate. Thus, the aroma of young red Mencia wines may be affected by levels of total anthocyanins. Copyright © 2013 Elsevier Ltd. All rights reserved.

Interactions among genetic variants in apoptosis pathway genes, reflux symptoms, body mass index, and smoking indicate two distinct etiologic patterns of esophageal adenocarcinoma.

PubMed

Zhai, Rihong; Chen, Feng; Liu, Geoffrey; Su, Li; Kulke, Matthew H; Asomaning, Kofi; Lin, Xihong; Heist, Rebecca S; Nishioka, Norman S; Sheu, Chau-Chyun; Wain, John C; Christiani, David C

2010-05-10

Apoptosis pathway, gastroesophageal reflux symptoms (reflux), higher body mass index (BMI), and tobacco smoking have been individually associated with esophageal adenocarcinoma (EA) development. However, how multiple factors jointly affect EA risk remains unclear. In total, 305 patients with EA and 339 age- and sex-matched controls were studied. High-order interactions among reflux, BMI, smoking, and functional polymorphisms in five apoptotic genes (FAS, FASL, IL1B, TP53BP, and BAT3) were investigated by entropy-based multifactor dimensionality reduction (MDR), classification and regression tree (CART), and traditional logistic regression (LR) models. In LR analysis, reflux, BMI, and smoking were significantly associated with EA risk, with reflux as the strongest individual factor. No individual single nucleotide polymorphism was associated with EA susceptibility. However, there was a two-way interaction between IL1B + 3954C>T and reflux (P = .008). In both CART and MDR analyses, reflux was also the strongest individual factor for EA risk. In individuals with reflux symptoms, CART analysis indicated that strongest interaction was among variant genotypes of IL1B + 3954C>T and BAT3S625P, higher BMI, and smoking (odds ratio [OR], 5.76; 95% CI, 2.48 to 13.38), a finding independently found using MDR analysis. In contrast, for participants without reflux symptoms, the strongest interaction was found between higher BMI and smoking (OR, 3.27; 95% CI, 1.88 to 5.68), also echoed by entropy-based MDR analysis. Although a history of reflux is an important risk for EA, multifactor interactions also play important roles in EA risk. Gene-environment interaction patterns differ between patients with and without reflux symptoms.

Gene-gene interactions among genetic variants from obesity candidate genes for nonobese and obese populations in type 2 diabetes.

PubMed

Lin, Eugene; Pei, Dee; Huang, Yi-Jen; Hsieh, Chang-Hsun; Wu, Lawrence Shih-Hsin

2009-08-01

Recent studies indicate that obesity may play a key role in modulating genetic predispositions to type 2 diabetes (T2D). This study examines the main effects of both single-locus and multilocus interactions among genetic variants in Taiwanese obese and nonobese individuals to test the hypothesis that obesity-related genes may contribute to the etiology of T2D independently and/or through such complex interactions. We genotyped 11 single nucleotide polymorphisms for 10 obesity candidate genes including adrenergic beta-2-receptor surface, adrenergic beta-3-receptor surface, angiotensinogen, fat mass and obesity associated gene, guanine nucleotide binding protein beta polypeptide 3 (GNB3), interleukin 6 receptor, proprotein convertase subtilisin/kexin type 1 (PCSK1), uncoupling protein 1, uncoupling protein 2, and uncoupling protein 3. There were 389 patients diagnosed with T2D and 186 age- and sex-matched controls. Single-locus analyses showed significant main effects of the GNB3 and PCSK1 genes on the risk of T2D among the nonobese group (p = 0.002 and 0.047, respectively). Further, interactions involving GNB3 and PCSK1 were suggested among the nonobese population using the generalized multifactor dimensionality reduction method (p = 0.001). In addition, interactions among angiotensinogen, fat mass and obesity associated gene, GNB3, and uncoupling protein 3 genes were found in a significant four-locus generalized multifactor dimensionality reduction model among the obese population (p = 0.001). The results suggest that the single nucleotide polymorphisms from the obesity candidate genes may contribute to the risk of T2D independently and/or in an interactive manner according to the presence or absence of obesity.

Probabilistic evaluation of uncertainties and risks in aerospace components

NASA Technical Reports Server (NTRS)

Shah, A. R.; Shiao, M. C.; Nagpal, V. K.; Chamis, C. C.

1992-01-01

This paper summarizes a methodology developed at NASA Lewis Research Center which computationally simulates the structural, material, and load uncertainties associated with Space Shuttle Main Engine (SSME) components. The methodology was applied to evaluate the scatter in static, buckling, dynamic, fatigue, and damage behavior of the SSME turbo pump blade. Also calculated are the probability densities of typical critical blade responses, such as effective stress, natural frequency, damage initiation, most probable damage path, etc. Risk assessments were performed for different failure modes, and the effect of material degradation on the fatigue and damage behaviors of a blade were calculated using a multi-factor interaction equation. Failure probabilities for different fatigue cycles were computed and the uncertainties associated with damage initiation and damage propagation due to different load cycle were quantified. Evaluations on the effects of mistuned blades on a rotor were made; uncertainties in the excitation frequency were found to significantly amplify the blade responses of a mistuned rotor. The effects of the number of blades on a rotor were studied. The autocorrelation function of displacements and the probability density function of the first passage time for deterministic and random barriers for structures subjected to random processes also were computed. A brief discussion was included on the future direction of probabilistic structural analysis.

A primer on multifactor productivity : description, benefits, and uses

DOT National Transportation Integrated Search

2008-04-01

This primer presents a description of multifactor : productivity (MFP) and its calculation. Productivity : is an important measure of the state of the : economy at various levels: firm, industry, sectoral, : and the macroeconomic. The method describe...

Information-Theoretic Metrics for Visualizing Gene-Environment Interactions

PubMed Central

Chanda, Pritam ; Zhang, Aidong ; Brazeau, Daniel ; Sucheston, Lara ; Freudenheim, Jo L. ; Ambrosone, Christine ; Ramanathan, Murali 

2007-01-01

The purpose of our work was to develop heuristics for visualizing and interpreting gene-environment interactions (GEIs) and to assess the dependence of candidate visualization metrics on biological and study-design factors. Two information-theoretic metrics, the k-way interaction information (KWII) and the total correlation information (TCI), were investigated. The effectiveness of the KWII and TCI to detect GEIs in a diverse range of simulated data sets and a Crohn disease data set was assessed. The sensitivity of the KWII and TCI spectra to biological and study-design variables was determined. Head-to-head comparisons with the relevance-chain, multifactor dimensionality reduction, and the pedigree disequilibrium test (PDT) methods were obtained. The KWII and TCI spectra, which are graphical summaries of the KWII and TCI for each subset of environmental and genotype variables, were found to detect each known GEI in the simulated data sets. The patterns in the KWII and TCI spectra were informative for factors such as case-control misassignment, locus heterogeneity, allele frequencies, and linkage disequilibrium. The KWII and TCI spectra were found to have excellent sensitivity for identifying the key disease-associated genetic variations in the Crohn disease data set. In head-to-head comparisons with the relevance-chain, multifactor dimensionality reduction, and PDT methods, the results from visual interpretation of the KWII and TCI spectra performed satisfactorily. The KWII and TCI are promising metrics for visualizing GEIs. They are capable of detecting interactions among numerous single-nucleotide polymorphisms and environmental variables for a diverse range of GEI models. PMID:17924337

An analysis of labor and multifactor productivity in air transportation : 1990 - 2001

DOT National Transportation Integrated Search

2002-01-01

The analysis has two main objectives: 1) to examine : labor productivity and multifactor productivity : (MFP) in U.S. air transportation during the 1990 : to 2001 period and to compare these measures to : those of two other transportation subsectors ...

A comparison of linear and nonlinear statistical techniques in performance attribution.

PubMed

Chan, N H; Genovese, C R

2001-01-01

Performance attribution is usually conducted under the linear framework of multifactor models. Although commonly used by practitioners in finance, linear multifactor models are known to be less than satisfactory in many situations. After a brief survey of nonlinear methods, nonlinear statistical techniques are applied to performance attribution of a portfolio constructed from a fixed universe of stocks using factors derived from some commonly used cross sectional linear multifactor models. By rebalancing this portfolio monthly, the cumulative returns for procedures based on standard linear multifactor model and three nonlinear techniques-model selection, additive models, and neural networks-are calculated and compared. It is found that the first two nonlinear techniques, especially in combination, outperform the standard linear model. The results in the neural-network case are inconclusive because of the great variety of possible models. Although these methods are more complicated and may require some tuning, toolboxes are developed and suggestions on calibration are proposed. This paper demonstrates the usefulness of modern nonlinear statistical techniques in performance attribution.

Actor-network Procedures: Modeling Multi-factor Authentication, Device Pairing, Social Interactions

DTIC Science & Technology

2011-08-29

unmodifiable properties of your body; or the capabilities that you cannot convey to others, such as your handwriting . An identity can thus be determined by...network, two principals with the same set of secrets but, say , different computational powers, can be distinguished by timing their responses. Or they... says that configurations are finite sets. Partially ordered multisets, or pomsets were introduced and extensively studied by Vaughan Pratt and his

Multifactor Screener in the 2000 National Health Interview Survey Cancer Control Supplement: Validation Results

Cancer.gov

Risk Factor Assessment Branch (RFAB) staff have assessed the validity of the Multifactor Screener in several studies: NCI's Observing Protein and Energy (OPEN) Study, the Eating at America's Table Study (EATS), and the joint NIH-AARP Diet and Health Study.

Multifactor Screener in the 2000 National Health Interview Survey Cancer Control Supplement: Overview

Cancer.gov

The Multifactor Screener may be useful to assess approximate intakes of fruits and vegetables, percentage energy from fat, and fiber. The screener asks respondents to report how frequently they consume foods in 16 categories. The screener also asks one question about the type of milk consumed.

Multifactor Screener in the 2000 National Health Interview Survey Cancer Control Supplement: Uses of Screener Estimates

Cancer.gov

Dietary intake estimates derived from the Multifactor Screener are rough estimates of usual intake of fruits and vegetables, fiber, calcium, servings of dairy, and added sugar. These estimates are not as accurate as those from more detailed methods (e.g., 24-hour recalls).

Can elevated CO2 modify regeneration from seed banks of floating freshwater marshes subjected to rising sea-level?

USGS Publications Warehouse

Middleton, Beth A.; McKee, Karen L.

2012-01-01

Higher atmospheric concentrations of CO2 can offset the negative effects of flooding or salinity on plant species, but previous studies have focused on mature, rather than regenerating vegetation. This study examined how interacting environments of CO2, water regime, and salinity affect seed germination and seedling biomass of floating freshwater marshes in the Mississippi River Delta, which are dominated by C3 grasses, sedges, and forbs. Germination density and seedling growth of the dominant species depended on multifactor interactions of CO2 (385 and 720 μl l-1) with flooding (drained, +8-cm depth, +8-cm depth-gradual) and salinity (0, 6% seawater) levels. Of the three factors tested, salinity was the most important determinant of seedling response patterns. Species richness (total = 19) was insensitive to CO2. Our findings suggest that for freshwater marsh communities, seedling response to CO2 is species-specific and secondary to salinity and flooding effects. Elevated CO2 did not ameliorate flooding or salinity stress. Consequently, climate-related changes in sea level or human-caused alterations in hydrology may override atmospheric CO2 concentrations in driving shifts in this plant community. The results of this study suggest caution in making extrapolations from species-specific responses to community-level predictions without detailed attention to the nuances of multifactor responses.

Cautionary Note on Reporting Eta-Squared Values from Multifactor ANOVA Designs

ERIC Educational Resources Information Center

Pierce, Charles A.; Block, Richard A.; Aguinis, Herman

2004-01-01

The authors provide a cautionary note on reporting accurate eta-squared values from multifactor analysis of variance (ANOVA) designs. They reinforce the distinction between classical and partial eta-squared as measures of strength of association. They provide examples from articles published in premier psychology journals in which the authors…

Forest ecosystems of a Lower Gulf Coastal Plainlandscape: multifactor classification and analysis

Treesearch

P. Charles Goebel; Brian J. Palik; L. Katherine Kirkman; Mark B. Drew; Larry West; Dee C. Pederson

2001-01-01

The most common forestland classification techniques applied in the southeastern United States are vegetation-based. While not completely ignored, the application of multifactor, hierarchical ecosystem classifications are limited despite their widespread use in other regions of the eastern United States. We present one of the few truly integrated ecosystem...

A Multifactor Ecosystem Assessment of Wetlands Created Using a Novel Dredged Material Placement Technique in the Atchafalaya River, Louisiana: An Engineering With Nature Demonstration Project

DTIC Science & Technology

functions. The strategic placement of dredged materials in locations that mimic natural process promoted additional ecological benefits, especially...regarding wading bird and infaunal habitat, thus adhering to Engineering With Nature (EWN) processes. The multifactor approach improved the wetland

Sensitivity Analysis of Mechanical Parameters of Different Rock Layers to the Stability of Coal Roadway in Soft Rock Strata

PubMed Central

Zhao, Zeng-hui; Wang, Wei-ming; Gao, Xin; Yan, Ji-xing

2013-01-01

According to the geological characteristics of Xinjiang Ili mine in western area of China, a physical model of interstratified strata composed of soft rock and hard coal seam was established. Selecting the tunnel position, deformation modulus, and strength parameters of each layer as influencing factors, the sensitivity coefficient of roadway deformation to each parameter was firstly analyzed based on a Mohr-Columb strain softening model and nonlinear elastic-plastic finite element analysis. Then the effect laws of influencing factors which showed high sensitivity were further discussed. Finally, a regression model for the relationship between roadway displacements and multifactors was obtained by equivalent linear regression under multiple factors. The results show that the roadway deformation is highly sensitive to the depth of coal seam under the floor which should be considered in the layout of coal roadway; deformation modulus and strength of coal seam and floor have a great influence on the global stability of tunnel; on the contrary, roadway deformation is not sensitive to the mechanical parameters of soft roof; roadway deformation under random combinations of multi-factors can be deduced by the regression model. These conclusions provide theoretical significance to the arrangement and stability maintenance of coal roadway. PMID:24459447

On the Interface of Probabilistic and PDE Methods in a Multifactor Term Structure Theory

ERIC Educational Resources Information Center

Mamon, Rogemar S.

2004-01-01

Within the general framework of a multifactor term structure model, the fundamental partial differential equation (PDE) satisfied by a default-free zero-coupon bond price is derived via a martingale-oriented approach. Using this PDE, a result characterizing a model belonging to an exponential affine class is established using only a system of…

Measurement Invariance of Second-Order Factor Model of the Multifactor Leadership Questionnaire (MLQ) across K-12 Principal Gender

ERIC Educational Resources Information Center

Xu, Lihua; Wubbena, Zane; Stewart, Trae

2016-01-01

Purpose: The purpose of this paper is to investigate the factor structure and the measurement invariance of the Multifactor Leadership Questionnaire (MLQ) across gender of K-12 school principals (n=6,317) in the USA. Design/methodology/approach: Nine first-order factor models and four second-order factor models were tested using confirmatory…

Bullying among adolescents in North Cyprus and Turkey: testing a multifactor model.

PubMed

Bayraktar, Fatih

2012-04-01

Peer bullying has been studied since the 1970s. Therefore, a vast literature has accumulated about the various predictors of bullying. However, to date there has been no study which has combined individual-, peer-, parental-, teacher-, and school-related predictors of bullying within a model. In this sense, the main aim of this study was to test a multifactor model of bullying among adolescents in North Cyprus and Turkey. A total of 1,052 adolescents (554 girls, 498 boys) aged between 13 and 18 (M = 14.7, SD = 1.17) were recruited from North Cyprus and Turkey. Before testing the multifactor models, the measurement models were tested according to structural equation modeling propositions. Both models indicated that the psychological climate of the school, teacher attitudes within classroom, peer relationships, parental acceptance-rejection, and individual social competence factors had significant direct effects on bullying behaviors. Goodness-of-fit indexes indicated that the proposed multifactor model fitted both data well. The strongest predictors of bullying were the psychological climate of the school following individual social competence factors and teacher attitudes within classroom in both samples. All of the latent variables explained 44% and 51% of the variance in bullying in North Cyprus and Turkey, respectively.

Potential barriers to the application of multi-factor portfolio analysis in public hospitals: evidence from a pilot study in the Netherlands.

PubMed

Pavlova, Milena; Tsiachristas, Apostolos; Vermaeten, Gerhard; Groot, Wim

2009-01-01

Portfolio analysis is a business management tool that can assist health care managers to develop new organizational strategies. The application of portfolio analysis to US hospital settings has been frequently reported. In Europe however, the application of this technique has received little attention, especially concerning public hospitals. Therefore, this paper examines the peculiarities of portfolio analysis and its applicability to the strategic management of European public hospitals. The analysis is based on a pilot application of a multi-factor portfolio analysis in a Dutch university hospital. The nature of portfolio analysis and the steps in a multi-factor portfolio analysis are reviewed along with the characteristics of the research setting. Based on these data, a multi-factor portfolio model is developed and operationalized. The portfolio model is applied in a pilot investigation to analyze the market attractiveness and hospital strengths with regard to the provision of three orthopedic services: knee surgery, hip surgery, and arthroscopy. The pilot portfolio analysis is discussed to draw conclusions about potential barriers to the overall adoption of portfolio analysis in the management of a public hospital. Copyright (c) 2008 John Wiley & Sons, Ltd.

Multi-factor authentication

DOEpatents

Hamlet, Jason R; Pierson, Lyndon G

2014-10-21

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

The Multi-factor Predictive Seis &Gis Model of Ecological, Genetical, Population Health Risk and Bio-geodynamic Processes In Geopathogenic Zones

NASA Astrophysics Data System (ADS)

Bondarenko, Y.

I. Goal and Scope. Human birth rate decrease, death-rate growth and increase of mu- tagenic deviations risk take place in geopathogenic and anthropogenic hazard zones. Such zones create unfavourable conditions for reproductive process of future genera- tions. These negative trends should be considered as a protective answer of the com- plex biosocial system to the appearance of natural and anthropogenic risk factors that are unfavourable for human health. The major goals of scientific evaluation and de- crease of risk of appearance of hazardous processes on the territory of Dnipropetrovsk, along with creation of the multi-factor predictive Spirit-Energy-Information Space "SEIS" & GIS Model of ecological, genetical and population health risk in connection with dangerous bio-geodynamic processes, were: multi-factor modeling and correla- tion of natural and anthropogenic environmental changes and those of human health; determination of indicators that show the risk of destruction structures appearance on different levels of organization and functioning of the city ecosystem (geophys- ical and geochemical fields, soil, hydrosphere, atmosphere, biosphere); analysis of regularities of natural, anthropogenic, and biological rhythms' interactions. II. Meth- ods. The long spatio-temporal researches (Y. Bondarenko, 1996, 2000) have proved that the ecological, genetic and epidemiological processes are in connection with de- velopment of dangerous bio-geophysical and bio-geodynamic processes. Mathemat- ical processing of space photos, lithogeochemical and geophysical maps with use of JEIS o and ERDAS o computer systems was executed at the first stage of forma- tion of multi-layer geoinformation model "Dnipropetrovsk ARC View GIS o. The multi-factor nonlinear correlation between solar activity and cosmic ray variations, geophysical, geodynamic, geochemical, atmospheric, technological, biological, socio- economical processes and oncologic case rate frequency, general and primary popula- tion sickness cases in Dnipropetrovsk City (1.2 million persons) are described by the multi-factor predictive SEIS & GIS model of geopathogenic zones that determines the human health risk and hazards. Results and Conclusions. We have created the SEIS system and multi-factor predictive SEIS model for the analysis of phase-metric spatio- 1 temporal nonlinear correlation and variations of rhythms of human health, ecological, genetic, epidemiological risks, demographic, socio-economic, bio-geophysical, bio- geodynamic processes in geopathogenic hazard zones. Cosmophotomaps "CPM" of vegetation index, anthropogenic-landscape and landscape-geophysical human health risk of Dnipropetrovsk City present synthesis-based elements of multi-layer GIS, which include multispectral images SPOT o, maps of different geophysical, geochem- ical, anthropogenic and citogenic risk factors, maps of integral oncologic case rate frequency, general and primary population sickness cases for administrative districts. Results of multi-layer spatio-temporal correlation of geophysical field parameters and variations of population sickness rate rhythms have enabled us to state grounds and to develop medico-biological and bio-geodynamic classification of geopathogenic zones. Bio-geodynamic model has served to define contours of anthropogenic-landscape and landscape-geophysical human health risk in Dnipropetrovsk City. Biorhythmic vari- ations give foundation for understanding physiological mechanisms of organism`s adaptation to extreme helio-geophysical and bio-geodynamic environmental condi- tions, which are dictated by changes in Multi-factor Correlation Stress Field "MCSF" with deformation of 5D SEIS. Interaction between organism and environment results in continuous superpositioning of external (exogenic) Nuclear-Molecular-Cristallic "NMC" MCSF rhythms on internal (endogenic) Nuclear-Molecular-Cellular "NMCl" MCSF rhythms. Their resonance wave (energy-information) integration and disinte- gration are responsible for structural and functional state of different physiological systems. Herewith, complex restructurization of defense functions blocks the adapta- tion process and may turn to be the primary reason for phase shifting, process and biorhythms hindering, appearance of different deseases. Interaction of biorhythms with natural and anthropogenic rhythms specify the peculiar features of environ- mental adaptation of living species. Such interaction results in correlation of sea- sonal rhythms in variations of thermo-baro-geodynamic "TBG" parameters of am- bient air with toxic concentration and human health risk in Dnipropetrovsk City. Bio-geodynamic analysis of medical and demographic situations has provided for search of spatio-temporal correlation between rhythms of general and primary pop- ulation sickness cases and oncologic case rate frequency, other medico-demographic rhythms, natural processes (helio-geophysical, thermodynamic, geodynamic) and an- thropogenic processes (industrial and houschold waste disposal, toxic emissions and their concentration in ambient air). The year of 1986, the year of minimum helio- geophysical activity "2G1dG1" and maximum anthropogenic processes associated with changes in sickness and death rates of the population of Earth were synchronized. With account of quantum character of SEIS rhythms, 5 reference levels of desyn- chronized helio-geophysical and bio-geodynamic processes affecting population sick- ness rate have been specified within bio-geodynamic models. The first reference level 2 of SEIS desynchronization includes rhythms with period of 22,5 years: ... 1958,2; 1980,7; 2003,2; .... The second reference level of SEIS desynchronization includes rhythms with period of 11,25 years: ... 1980,7; 1992; 2003,2;.... The third reference level covers 5,625-years periodic rhythms2:... 1980,7; 1986,3; 1992; 1997,6; 2003,2; .... The fourth quantum reference level includes rhythms 3 with period of 2,8125 years: ... 1980,7; 1983,5; 1986,3; 1989,1; 1992; 1994,8; 1997,6; 2000,4; 2003,2; .... Rhythms with 1,40625-years period fall is fifth reference level of SEIS desynchro- nization: ...1980,7; 1982,1; 1983,5; 1984,9; 1986,3; 1987,7; 1989,1; 1990,5; 1992; 1993,3; 1994,8; 1996,2; 1997,6; 1999; 2000,4; 2001,8; 2003,2;.... Analysis of alternat- ing medical and demographic situation in Ukraine (1981-1992)and in Dnipropetrovsk (1988-1995)has allowed to back up theoretical model of various-level rhythm quan- tum, with non-linear regularities due to phase-metric spatio-temporal deformation be- ing specified. Application of new technologies of Risk Analysis, Sinthesis and SEIS Modeling at the choice of a burial place for dangerous radioactive wastes in the zone of Chernobyl nuclear disaster (Shestopalov V., Bondarenko Y...., 1998) has shown their very high efficiency in comparison with GIS Analysis. IV.Recommendations and Outlook. In order to draw a conclusion regarding bio-geodynamic modeling of spatio-temporal structure of areas where common childhood sickness rate exists, it is necessary to mention that the only thing that can favour to exact predicting of where and when important catastrophes and epidemies will take place is correct and complex bio-geodynamic modeling. Imperfection of present GIS is the result of the lack of interactive facilities for multi-factor modeling of nonlinear natural and an- thropogenic processes. Equations' coefficients calculated for some areas are often irrelevant when applied to others. In this connection there arises a number of prob- lems concerning practical application and reliability of GIS-models that are used to carry out efficient ecological monitoring. References Bondarenko Y., 1997, Drawing up Cosmophotomaps and Multi-factor Forecasting of Hazard of Development of Dan- gerous Geodynamic Processes in Dnipropetrovsk,The Technically-Natural Problems of failures and catastrophes in connection with development of dangerous geological processes, Kiev, Ukraine, 1997. Bondarenko Y., 1997, The Methodology of a State the Value of Quality of the Ground and the House Level them Ecology-Genetic-Toxic of the human health risk based on multi-layer cartographical model", Experience of application GIS - Technologies for creating Cadastral Systems, Yalta, Ukraine, 1997, p. 39-40. Shestopalov V., Bondarenko Y., Zayonts I., Rudenko Y. , Bohuslavsky A., 1998, Complexation of Structural-Geodynamical and Hydrogeological Methods of Studying Areas to Reveal Geological Structural Perspectives for Deep Isolation of Radioactive Wastes, Field Testing and Associated Modeling of Potential High-Level Nuclear Waste Geologic Disposal Sites, Berkeley, USA, 1998, p.81-82. 3

The Research of Regression Method for Forecasting Monthly Electricity Sales Considering Coupled Multi-factor

NASA Astrophysics Data System (ADS)

Wang, Jiangbo; Liu, Junhui; Li, Tiantian; Yin, Shuo; He, Xinhui

2018-01-01

The monthly electricity sales forecasting is a basic work to ensure the safety of the power system. This paper presented a monthly electricity sales forecasting method which comprehensively considers the coupled multi-factors of temperature, economic growth, electric power replacement and business expansion. The mathematical model is constructed by using regression method. The simulation results show that the proposed method is accurate and effective.

Biometric Data Safeguarding Technologies Analysis and Best Practices

DTIC Science & Technology

2011-12-01

fuzzy vault” scheme proposed by Juels and Sudan. The scheme was designed to encrypt data such that it could be unlocked by similar but inexact matches... designed transform functions. Multifactor Key Generation Multifactor key generation combines a biometric with one or more other inputs, such as a...cooperative, off-angle iris images.  Since the commercialized system is designed for images acquired from a specific, paired acquisition system

Application of GA-SVM method with parameter optimization for landslide development prediction

NASA Astrophysics Data System (ADS)

Li, X. Z.; Kong, J. M.

2013-10-01

Prediction of landslide development process is always a hot issue in landslide research. So far, many methods for landslide displacement series prediction have been proposed. Support vector machine (SVM) has been proved to be a novel algorithm with good performance. However, the performance strongly depends on the right selection of the parameters (C and γ) of SVM model. In this study, we presented an application of GA-SVM method with parameter optimization in landslide displacement rate prediction. We selected a typical large-scale landslide in some hydro - electrical engineering area of Southwest China as a case. On the basis of analyzing the basic characteristics and monitoring data of the landslide, a single-factor GA-SVM model and a multi-factor GA-SVM model of the landslide were built. Moreover, the models were compared with single-factor and multi-factor SVM models of the landslide. The results show that, the four models have high prediction accuracies, but the accuracies of GA-SVM models are slightly higher than those of SVM models and the accuracies of multi-factor models are slightly higher than those of single-factor models for the landslide prediction. The accuracy of the multi-factor GA-SVM models is the highest, with the smallest RSME of 0.0009 and the biggest RI of 0.9992.

Multifactor dimensionality reduction reveals a three-locus epistatic interaction associated with susceptibility to pulmonary tuberculosis.

PubMed

Collins, Ryan L; Hu, Ting; Wejse, Christian; Sirugo, Giorgio; Williams, Scott M; Moore, Jason H

2013-02-18

Identifying high-order genetics associations with non-additive (i.e. epistatic) effects in population-based studies of common human diseases is a computational challenge. Multifactor dimensionality reduction (MDR) is a machine learning method that was designed specifically for this problem. The goal of the present study was to apply MDR to mining high-order epistatic interactions in a population-based genetic study of tuberculosis (TB). The study used a previously published data set consisting of 19 candidate single-nucleotide polymorphisms (SNPs) in 321 pulmonary TB cases and 347 healthy controls from Guniea-Bissau in Africa. The ReliefF algorithm was applied first to generate a smaller set of the five most informative SNPs. MDR with 10-fold cross-validation was then applied to look at all possible combinations of two, three, four and five SNPs. The MDR model with the best testing accuracy (TA) consisted of SNPs rs2305619, rs187084, and rs11465421 (TA = 0.588) in PTX3, TLR9 and DC-Sign, respectively. A general 1000-fold permutation test of the null hypothesis of no association confirmed the statistical significance of the model (p = 0.008). An additional 1000-fold permutation test designed specifically to test the linear null hypothesis that the association effects are only additive confirmed the presence of non-additive (i.e. nonlinear) or epistatic effects (p = 0.013). An independent information-gain measure corroborated these results with a third-order epistatic interaction that was stronger than any lower-order associations. We have identified statistically significant evidence for a three-way epistatic interaction that is associated with susceptibility to TB. This interaction is stronger than any previously described one-way or two-way associations. This study highlights the importance of using machine learning methods that are designed to embrace, rather than ignore, the complexity of common diseases such as TB. We recommend future studies of the genetics of TB take into account the possibility that high-order epistatic interactions might play an important role in disease susceptibility.

Gene-gene interactions of CYP2A6 and MAOA polymorphisms on smoking behavior in Chinese male population.

PubMed

Tang, Xun; Guo, Song; Sun, Hongqiang; Song, Xuemei; Jiang, Zuonin; Sheng, Lixiang; Zhou, Dongfeng; Hu, Yonghua; Chen, Dafang

2009-05-01

Nicotine is the major psychoactive ingredient in tobacco, and is responsible for dependence through the nicotine-stimulated reward pathway mediated by the central dopaminergic system. Consequently, genetic polymorphisms in both nicotine metabolism and dopamine catabolism genes may influence smoking behavior, and interact with each other resulting in risk modulation. In this study, we investigated the association and multilocus gene-gene interactions of cytochrome P450 2A6 (CYP2A6), dopamine beta-hydroxylase (DBH), catechol O-methyl transferase (COMT), and monoamine oxidase A (MAOA) polymorphisms with smoking behavior in a community-based Chinese male population. The polymorphisms were genotyped in 203 current smokers, 66 former smokers, and 102 never smokers. Multivariate logistic regression models and the multifactor dimensionality reduction method were used to analyze the association and multilocus gene-gene interactions. Statistically significant trends were shown for increased risk of smoking initiation in participants with CYP2A6*1B/CYP2A6*1B genotypes compared with those with CYP2A6*1A/CYP2A6*1A genotypes [odds ratio (OR)=3.5, 95% confidence interval (CI)= 1.5-8.1], and participants with CYP2A6*1/CYP2A6*1 genotypes were at higher risk of smoking initiation (OR=2.4, 95% CI=1.2-4.5) and smoking persistence (OR=4.0, 95% CI=1.5-10.3) than those who have CYP2A6*4C genotypes. Moreover, the best model involved a gene-gene interaction between MAOA and CYP2A6 was characterized by the multifactor dimensionality reduction method (64.11% accuracy, P<0.001), and indicated that carriers of the combined 1460 T/O genotype for MAOA EcoRV and CYP2A6*1/CYP2A6*1 genotypes were at higher risk of smoking (OR=15.4, 95% CI=4.5-52.5). These findings suggested a substantial influence of CYP2A6 polymorphism as well as the interaction with MAOA resulting in risk modulation on smoking behavior in Chinese male population.

Multi-factor evaluation indicator method for the risk assessment of atmospheric and oceanic hazard group due to the attack of tropical cyclones

NASA Astrophysics Data System (ADS)

Qi, Peng; Du, Mei

2018-06-01

China's southeast coastal areas frequently suffer from storm surge due to the attack of tropical cyclones (TCs) every year. Hazards induced by TCs are complex, such as strong wind, huge waves, storm surge, heavy rain, floods, and so on. The atmospheric and oceanic hazards cause serious disasters and substantial economic losses. This paper, from the perspective of hazard group, sets up a multi-factor evaluation method for the risk assessment of TC hazards using historical extreme data of concerned atmospheric and oceanic elements. Based on the natural hazard dynamic process, the multi-factor indicator system is composed of nine natural hazard factors representing intensity and frequency, respectively. Contributing to the indicator system, in order of importance, are maximum wind speed by TCs, attack frequency of TCs, maximum surge height, maximum wave height, frequency of gusts ≥ Scale 8, rainstorm intensity, maximum tidal range, rainstorm frequency, then sea-level rising rate. The first four factors are the most important, whose weights exceed 10% in the indicator system. With normalization processing, all the single-hazard factors are superposed by multiplying their weights to generate a superposed TC hazard. The multi-factor evaluation indicator method was applied to the risk assessment of typhoon-induced atmospheric and oceanic hazard group in typhoon-prone southeast coastal cities of China.

Security enhanced multi-factor biometric authentication scheme using bio-hash function.

PubMed

Choi, Younsung; Lee, Youngsook; Moon, Jongho; Won, Dongho

2017-01-01

With the rapid development of personal information and wireless communication technology, user authentication schemes have been crucial to ensure that wireless communications are secure. As such, various authentication schemes with multi-factor authentication have been proposed to improve the security of electronic communications. Multi-factor authentication involves the use of passwords, smart cards, and various biometrics to provide users with the utmost privacy and data protection. Cao and Ge analyzed various authentication schemes and found that Younghwa An's scheme was susceptible to a replay attack where an adversary masquerades as a legal server and a user masquerading attack where user anonymity is not provided, allowing an adversary to execute a password change process by intercepting the user's ID during login. Cao and Ge improved upon Younghwa An's scheme, but various security problems remained. This study demonstrates that Cao and Ge's scheme is susceptible to a biometric recognition error, slow wrong password detection, off-line password attack, user impersonation attack, ID guessing attack, a DoS attack, and that their scheme cannot provide session key agreement. Then, to address all weaknesses identified in Cao and Ge's scheme, this study proposes a security enhanced multi-factor biometric authentication scheme and provides a security analysis and formal analysis using Burrows-Abadi-Needham logic. Finally, the efficiency analysis reveals that the proposed scheme can protect against several possible types of attacks with only a slightly high computational cost.

Interactions between above- and belowground organisms modified in climate change experiments

NASA Astrophysics Data System (ADS)

Stevnbak, Karen; Scherber, Christoph; Gladbach, David J.; Beier, Claus; Mikkelsen, Teis N.; Christensen, Søren

2012-11-01

Climate change has been shown to affect ecosystem process rates and community composition, with direct and indirect effects on belowground food webs. In particular, altered rates of herbivory under future climate can be expected to influence above-belowground interactions. Here, we use a multifactor, field-scale climate change experiment and independently manipulate atmospheric CO2 concentration, air and soil temperature and drought in all combinations since 2005. We show that changes in these factors modify the interaction between above- and belowground organisms. We use an insect herbivore to experimentally increase aboveground herbivory in grass phytometers exposed to all eight combinations of climate change factors for three years. Aboveground herbivory increased the abundance of belowground protozoans, microbial growth and microbial nitrogen availability. Increased CO2 modified these links through a reduction in herbivory and cascading effects through the soil food web. Interactions between CO2, drought and warming can affect belowground protozoan abundance. Our findings imply that climate change affects aboveground-belowground interactions through changes in nutrient availability.

Security enhanced multi-factor biometric authentication scheme using bio-hash function

PubMed Central

Lee, Youngsook; Moon, Jongho

2017-01-01

With the rapid development of personal information and wireless communication technology, user authentication schemes have been crucial to ensure that wireless communications are secure. As such, various authentication schemes with multi-factor authentication have been proposed to improve the security of electronic communications. Multi-factor authentication involves the use of passwords, smart cards, and various biometrics to provide users with the utmost privacy and data protection. Cao and Ge analyzed various authentication schemes and found that Younghwa An’s scheme was susceptible to a replay attack where an adversary masquerades as a legal server and a user masquerading attack where user anonymity is not provided, allowing an adversary to execute a password change process by intercepting the user’s ID during login. Cao and Ge improved upon Younghwa An’s scheme, but various security problems remained. This study demonstrates that Cao and Ge’s scheme is susceptible to a biometric recognition error, slow wrong password detection, off-line password attack, user impersonation attack, ID guessing attack, a DoS attack, and that their scheme cannot provide session key agreement. Then, to address all weaknesses identified in Cao and Ge’s scheme, this study proposes a security enhanced multi-factor biometric authentication scheme and provides a security analysis and formal analysis using Burrows-Abadi-Needham logic. Finally, the efficiency analysis reveals that the proposed scheme can protect against several possible types of attacks with only a slightly high computational cost. PMID:28459867

A graph-based approach to inequality assessment

NASA Astrophysics Data System (ADS)

Palestini, Arsen; Pignataro, Giuseppe

2016-08-01

In a population consisting of heterogeneous types, whose income factors are indicated by nonnegative vectors, policies aggregating different factors can be represented by coalitions in a cooperative game, whose characteristic function is a multi-factor inequality index. When it is not possible to form all coalitions, the feasible ones can be indicated by a graph. We redefine Shapley and Banzhaf values on graph games to deduce some properties involving the degrees of the graph vertices and marginal contributions to overall inequality. An example is finally provided based on a modified multi-factor Atkinson index.

Soil moisture surpasses elevated CO2 and temperature as a control on soil carbon dynamics in a multi-factor climate change experiment

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

Garten Jr, Charles T; Classen, Aimee T; Norby, Richard J

2009-01-01

Some single-factor experiments suggest that elevated CO2 concentrations can increase soil carbon, but few experiments have examined the effects of interacting environmental factors on soil carbon dynamics. We undertook studies of soil carbon and nitrogen in a multi-factor (CO2 x temperature x soil moisture) climate change experiment on a constructed old-field ecosystem. After four growing seasons, elevated CO2 had no measurable effect on carbon and nitrogen concentrations in whole soil, particulate organic matter (POM), and mineral-associated organic matter (MOM). Analysis of stable carbon isotopes, under elevated CO2, indicated between 14 and 19% new soil carbon under two different watering treatmentsmore » with as much as 48% new carbon in POM. Despite significant belowground inputs of new organic matter, soil carbon concentrations and stocks in POM declined over four years under soil moisture conditions that corresponded to prevailing precipitation inputs (1,300 mm yr-1). Changes over time in soil carbon and nitrogen under a drought treatment (approximately 20% lower soil water content) were not statistically significant. Reduced soil moisture lowered soil CO2 efflux and slowed soil carbon cycling in the POM pool. In this experiment, soil moisture (produced by different watering treatments) was more important than elevated CO2 and temperature as a control on soil carbon dynamics.« less

Multi-Factor Analysis for Selecting Lunar Exploration Soft Landing Area and the best Cruise Route

NASA Astrophysics Data System (ADS)

Mou, N.; Li, J.; Meng, Z.; Zhang, L.; Liu, W.

2018-04-01

Selecting the right soft landing area and planning a reasonable cruise route are the basic tasks of lunar exploration. In this paper, the Von Karman crater in the Antarctic Aitken basin on the back of the moon is used as the study area, and multi-factor analysis is used to evaluate the landing area and cruise route of lunar exploration. The evaluation system mainly includes the factors such as the density of craters, the impact area of craters, the formation of the whole area and the formation of some areas, such as the vertical structure, rock properties and the content of (FeO + TiO2), which can reflect the significance of scientific exploration factor. And the evaluation of scientific exploration is carried out on the basis of safety and feasibility. On the basis of multi-factor superposition analysis, three landing zones A, B and C are selected, and the appropriate cruising route is analyzed through scientific research factors. This study provides a scientific basis for the lunar probe landing and cruise route planning, and it provides technical support for the subsequent lunar exploration.

Multivariate generalized multifactor dimensionality reduction to detect gene-gene interactions

PubMed Central

2013-01-01

Background Recently, one of the greatest challenges in genome-wide association studies is to detect gene-gene and/or gene-environment interactions for common complex human diseases. Ritchie et al. (2001) proposed multifactor dimensionality reduction (MDR) method for interaction analysis. MDR is a combinatorial approach to reduce multi-locus genotypes into high-risk and low-risk groups. Although MDR has been widely used for case-control studies with binary phenotypes, several extensions have been proposed. One of these methods, a generalized MDR (GMDR) proposed by Lou et al. (2007), allows adjusting for covariates and applying to both dichotomous and continuous phenotypes. GMDR uses the residual score of a generalized linear model of phenotypes to assign either high-risk or low-risk group, while MDR uses the ratio of cases to controls. Methods In this study, we propose multivariate GMDR, an extension of GMDR for multivariate phenotypes. Jointly analysing correlated multivariate phenotypes may have more power to detect susceptible genes and gene-gene interactions. We construct generalized estimating equations (GEE) with multivariate phenotypes to extend generalized linear models. Using the score vectors from GEE we discriminate high-risk from low-risk groups. We applied the multivariate GMDR method to the blood pressure data of the 7,546 subjects from the Korean Association Resource study: systolic blood pressure (SBP) and diastolic blood pressure (DBP). We compare the results of multivariate GMDR for SBP and DBP to the results from separate univariate GMDR for SBP and DBP, respectively. We also applied the multivariate GMDR method to the repeatedly measured hypertension status from 5,466 subjects and compared its result with those of univariate GMDR at each time point. Results Results from the univariate GMDR and multivariate GMDR in two-locus model with both blood pressures and hypertension phenotypes indicate best combinations of SNPs whose interaction has significant association with risk for high blood pressures or hypertension. Although the test balanced accuracy (BA) of multivariate analysis was not always greater than that of univariate analysis, the multivariate BAs were more stable with smaller standard deviations. Conclusions In this study, we have developed multivariate GMDR method using GEE approach. It is useful to use multivariate GMDR with correlated multiple phenotypes of interests. PMID:24565370

Probabilistic Simulation of Combined Thermo-Mechanical Cyclic Fatigue in Composites

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2011-01-01

A methodology to compute probabilistically-combined thermo-mechanical fatigue life of polymer matrix laminated composites has been developed and is demonstrated. Matrix degradation effects caused by long-term environmental exposure and mechanical/thermal cyclic loads are accounted for in the simulation process. A unified time-temperature-stress-dependent multifactor-interaction relationship developed at NASA Glenn Research Center has been used to model the degradation/aging of material properties due to cyclic loads. The fast probability-integration method is used to compute probabilistic distribution of response. Sensitivities of fatigue life reliability to uncertainties in the primitive random variables (e.g., constituent properties, fiber volume ratio, void volume ratio, ply thickness, etc.) computed and their significance in the reliability-based design for maximum life is discussed. The effect of variation in the thermal cyclic loads on the fatigue reliability for a (0/+/-45/90)s graphite/epoxy laminate with a ply thickness of 0.127 mm, with respect to impending failure modes has been studied. The results show that, at low mechanical-cyclic loads and low thermal-cyclic amplitudes, fatigue life for 0.999 reliability is most sensitive to matrix compressive strength, matrix modulus, thermal expansion coefficient, and ply thickness. Whereas at high mechanical-cyclic loads and high thermal-cyclic amplitudes, fatigue life at 0.999 reliability is more sensitive to the shear strength of matrix, longitudinal fiber modulus, matrix modulus, and ply thickness.

Probabilistic Simulation for Combined Cycle Fatigue in Composites

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2010-01-01

A methodology to compute probabilistic fatigue life of polymer matrix laminated composites has been developed and demonstrated. Matrix degradation effects caused by long term environmental exposure and mechanical/thermal cyclic loads are accounted for in the simulation process. A unified time-temperature-stress dependent multifactor interaction relationship developed at NASA Glenn Research Center has been used to model the degradation/aging of material properties due to cyclic loads. The fast probability integration method is used to compute probabilistic distribution of response. Sensitivities of fatigue life reliability to uncertainties in the primitive random variables (e.g., constituent properties, fiber volume ratio, void volume ratio, ply thickness, etc.) computed and their significance in the reliability-based design for maximum life is discussed. The effect of variation in the thermal cyclic loads on the fatigue reliability for a (0/+/- 45/90)s graphite/epoxy laminate with a ply thickness of 0.127 mm, with respect to impending failure modes has been studied. The results show that, at low mechanical cyclic loads and low thermal cyclic amplitudes, fatigue life for 0.999 reliability is most sensitive to matrix compressive strength, matrix modulus, thermal expansion coefficient, and ply thickness. Whereas at high mechanical cyclic loads and high thermal cyclic amplitudes, fatigue life at 0.999 reliability is more sensitive to the shear strength of matrix, longitudinal fiber modulus, matrix modulus, and ply thickness.

Probabilistic Simulation of Combined Thermo-Mechanical Cyclic Fatigue in Composites

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2010-01-01

A methodology to compute probabilistically-combined thermo-mechanical fatigue life of polymer matrix laminated composites has been developed and is demonstrated. Matrix degradation effects caused by long-term environmental exposure and mechanical/thermal cyclic loads are accounted for in the simulation process. A unified time-temperature-stress-dependent multifactor-interaction relationship developed at NASA Glenn Research Center has been used to model the degradation/aging of material properties due to cyclic loads. The fast probability-integration method is used to compute probabilistic distribution of response. Sensitivities of fatigue life reliability to uncertainties in the primitive random variables (e.g., constituent properties, fiber volume ratio, void volume ratio, ply thickness, etc.) computed and their significance in the reliability-based design for maximum life is discussed. The effect of variation in the thermal cyclic loads on the fatigue reliability for a (0/+/-45/90)s graphite/epoxy laminate with a ply thickness of 0.127 mm, with respect to impending failure modes has been studied. The results show that, at low mechanical-cyclic loads and low thermal-cyclic amplitudes, fatigue life for 0.999 reliability is most sensitive to matrix compressive strength, matrix modulus, thermal expansion coefficient, and ply thickness. Whereas at high mechanical-cyclic loads and high thermal-cyclic amplitudes, fatigue life at 0.999 reliability is more sensitive to the shear strength of matrix, longitudinal fiber modulus, matrix modulus, and ply thickness.

Effect of Cyclic Thermo-Mechanical Loads on Fatigue Reliability in Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Shah, A. R.; Murthy, P. L. N.; Chamis, C. C.

1996-01-01

A methodology to compute probabilistic fatigue life of polymer matrix laminated composites has been developed and demonstrated. Matrix degradation effects caused by long term environmental exposure and mechanical/thermal cyclic loads are accounted for in the simulation process. A unified time-temperature-stress dependent multi-factor interaction relationship developed at NASA Lewis Research Center has been used to model the degradation/aging of material properties due to cyclic loads. The fast probability integration method is used to compute probabilistic distribution of response. Sensitivities of fatigue life reliability to uncertainties in the primitive random variables (e.g., constituent properties, fiber volume ratio, void volume ratio, ply thickness, etc.) computed and their significance in the reliability- based design for maximum life is discussed. The effect of variation in the thermal cyclic loads on the fatigue reliability for a (0/+/- 45/90)(sub s) graphite/epoxy laminate with a ply thickness of 0.127 mm, with respect to impending failure modes has been studied. The results show that, at low mechanical cyclic loads and low thermal cyclic amplitudes, fatigue life for 0.999 reliability is most sensitive to matrix compressive strength, matrix modulus, thermal expansion coefficient, and ply thickness. Whereas at high mechanical cyclic loads and high thermal cyclic amplitudes, fatigue life at 0.999 reliability is more sensitive to the shear strength of matrix, longitudinal fiber modulus, matrix modulus, and ply thickness.

The prevalence and structure of obsessive-compulsive personality disorder in Hispanic psychiatric outpatients

PubMed Central

Ansell, Emily B.; Pinto, Anthony; Crosby, Ross D.; Becker, Daniel F.; Añez, Luis M.; Paris, Manuel; Grilo, Carlos M.

2010-01-01

This study sought to confirm a multi-factor model of Obsessive-compulsive personality disorder (OCPD) in a Hispanic outpatient sample and to explore associations of the OCPD factors with aggression, depression, and suicidal thoughts. One hundred and thirty monolingual, Spanish-speaking participants were recruited from a community mental health center and were assessed by bilingual doctoral level clinicians. OCPD was highly prevalent (26%) in this sample. Multi-factor models of OCPD were tested and the two factors - perfectionism and interpersonal rigidity - provided the best model fit. Interpersonal rigidity was associated with aggression and anger while perfectionism was associated with depression and suicidal thoughts. PMID:20227063

A Multifactor Secure Authentication System for Wireless Payment

NASA Astrophysics Data System (ADS)

Sanyal, Sugata; Tiwari, Ayu; Sanyal, Sudip

Organizations are deploying wireless based online payment applications to expand their business globally, it increases the growing need of regulatory requirements for the protection of confidential data, and especially in internet based financial areas. Existing internet based authentication systems often use either the Web or the Mobile channel individually to confirm the claimed identity of the remote user. The vulnerability is that access is based on only single factor authentication which is not secure to protect user data, there is a need of multifactor authentication. This paper proposes a new protocol based on multifactor authentication system that is both secure and highly usable. It uses a novel approach based on Transaction Identification Code and SMS to enforce another security level with the traditional Login/password system. The system provides a highly secure environment that is simple to use and deploy with in a limited resources that does not require any change in infrastructure or underline protocol of wireless network. This Protocol for Wireless Payment is extended as a two way authentications system to satisfy the emerging market need of mutual authentication and also supports secure B2B communication which increases faith of the user and business organizations on wireless financial transaction using mobile devices.

Antioxidant Defense Enzyme Genes and Asthma Susceptibility: Gender-Specific Effects and Heterogeneity in Gene-Gene Interactions between Pathogenetic Variants of the Disease

PubMed Central

Polonikov, Alexey V.; Ivanov, Vladimir P.; Bogomazov, Alexey D.; Freidin, Maxim B.; Illig, Thomas; Solodilova, Maria A.

2014-01-01

Oxidative stress resulting from an increased amount of reactive oxygen species and an imbalance between oxidants and antioxidants plays an important role in the pathogenesis of asthma. The present study tested the hypothesis that genetic susceptibility to allergic and nonallergic variants of asthma is determined by complex interactions between genes encoding antioxidant defense enzymes (ADE). We carried out a comprehensive analysis of the associations between adult asthma and 46 single nucleotide polymorphisms of 34 ADE genes and 12 other candidate genes of asthma in Russian population using set association analysis and multifactor dimensionality reduction approaches. We found for the first time epistatic interactions between ADE genes underlying asthma susceptibility and the genetic heterogeneity between allergic and nonallergic variants of the disease. We identified GSR (glutathione reductase) and PON2 (paraoxonase 2) as novel candidate genes for asthma susceptibility. We observed gender-specific effects of ADE genes on the risk of asthma. The results of the study demonstrate complexity and diversity of interactions between genes involved in oxidative stress underlying susceptibility to allergic and nonallergic asthma. PMID:24895604

Probabilistic simulation of the human factor in structural reliability

NASA Technical Reports Server (NTRS)

Chamis, C. C.

1993-01-01

A formal approach is described in an attempt to computationally simulate the probable ranges of uncertainties of the human factor in structural probabilistic assessments. A multi-factor interaction equation (MFIE) model has been adopted for this purpose. Human factors such as marital status, professional status, home life, job satisfaction, work load and health, are considered to demonstrate the concept. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Suitability of the MFIE in the subsequently probabilistic sensitivity studies are performed to assess the validity of the whole approach. Results obtained show that the uncertainties for no error range from five to thirty percent for the most optimistic case.

Probabilistic simulation of the human factor in structural reliability

NASA Astrophysics Data System (ADS)

Chamis, Christos C.; Singhal, Surendra N.

1994-09-01

The formal approach described herein computationally simulates the probable ranges of uncertainties for the human factor in probabilistic assessments of structural reliability. Human factors such as marital status, professional status, home life, job satisfaction, work load, and health are studied by using a multifactor interaction equation (MFIE) model to demonstrate the approach. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Subsequently performed probabilistic sensitivity studies assess the suitability of the MFIE as well as the validity of the whole approach. Results show that uncertainties range from 5 to 30 percent for the most optimistic case, assuming 100 percent for no error (perfect performance).

Probabilistic Simulation of the Human Factor in Structural Reliability

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Singhal, Surendra N.

1994-01-01

The formal approach described herein computationally simulates the probable ranges of uncertainties for the human factor in probabilistic assessments of structural reliability. Human factors such as marital status, professional status, home life, job satisfaction, work load, and health are studied by using a multifactor interaction equation (MFIE) model to demonstrate the approach. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Subsequently performed probabilistic sensitivity studies assess the suitability of the MFIE as well as the validity of the whole approach. Results show that uncertainties range from 5 to 30 percent for the most optimistic case, assuming 100 percent for no error (perfect performance).

Severe chronic heart failure in patients considered for heart transplantation in Poland.

PubMed

Korewicki, Jerzy; Leszek, Przemysław; Zieliński, Tomasz; Rywik, Tomasz; Piotrowski, Walerian; Kurjata, Paweł; Kozar-Kamińska, Katarzyna; Kodziszewska, Katarzyna

2012-01-01

Based on the results of clinical trials, the prognosis for patients with severe heart failure (HF) has improved over the last 20 years. However, clinical trials do not reflect 'real life' due to patient selection. Thus, the aim of the POLKARD-HF registry was the analysis of survival of patients with refractory HF referred for orthotopic heart transplantation (OHT). Between 1 November 2003 and 31 October 2007, 983 patients with severe HF, referred for OHT in Poland, were included into the registry. All patients underwent routine clinical and hemodynamic evaluation, with NT-proBNP and hsCRP assessment. Death or an emergency OHT were assumed as the endpoints. The average observation period was 601 days. Kaplan-Meier curves with log-rank and univariate together with multifactor Cox regression model the stepwise variable selection method were used to determine the predictive value of analyzed variables. Among the 983 patients, the probability of surviving for one year was approximately 80%, for two years 70%, and for three years 67%. Etiology of the HF did not significantly influence the prognosis. The patients in NYHA class IV had a three-fold higher risk of death or emergency OHT. The univariate/multifactor Cox regression analysis revealed that NYHA IV class (HR 2.578, p < 0.0001), HFSS score (HR 2.572, p < 0.0001) and NT-proBNP plasma level (HR 1.600, p = 0.0200), proved to influence survival without death or emergency OHT. Despite optimal treatment, the prognosis for patients with refractory HF is still not good. NYHA class IV, NT-proBNP and HFSS score can help define the highest risk group. The results are consistent with the prognosis of patients enrolled into the randomized trials.

Enhancing leadership and relationships by implementing a peer mentoring program.

PubMed

Gafni Lachter, Liat R; Ruland, Judith P

2018-03-30

Peer-mentoring is often described as effective means to promote professional and leadership skills, yet evidence on practical models of such programs for occupational therapy students are sparse. The purpose of this study was to evaluate the outcomes of a peer-mentoring program designed for graduate occupational therapy students. Forty-seven second-year student volunteers were randomly assigned to individually mentor first-year students in a year-long program. Students met biweekly virtually or in person to provide mentorship on everyday student issues, according to mentees' needs. Faculty-led group activities prior and during the peer-mentoring program took place to facilitate the mentorship relationships. Program effectiveness was measured using the Multi-factor Leadership Questionnaire (Avolio & Bass, MLQ: Multifactor Leadership Questionnaire, 2004) and an open-ended feedback survey. Results of multi-variate MANOVA for repeated measures indicating significant enhancement in several leadership skills (F(12,46) = 4.0, P = 0.001, η 2  = 0.579). Qualitative data from feedback surveys indicated that an opportunity to help; forming relationships; and structure as enabler were perceived as important participation outcomes. Students expressed high satisfaction and perceived value from their peer-mentoring experience. As we seek ways to promote our profession and the leadership of its members, it is recommended to consider student peer-mentoring to empower them to practice and advance essential career skills from the initial stages of professional development. Evidence found in this study demonstrates that peer-mentoring programs can promote leadership development and establishment of networks in an occupational therapy emerging professional community, at a low cost. The peer-mentoring blueprint and lessons learned are presented with hopes to inspire others to implement peer-mentoring programs in their settings. © 2018 Occupational Therapy Australia.

The prevalence and structure of obsessive-compulsive personality disorder in Hispanic psychiatric outpatients.

PubMed

Ansell, Emily B; Pinto, Anthony; Crosby, Ross D; Becker, Daniel F; Añez, Luis M; Paris, Manuel; Grilo, Carlos M

2010-09-01

This study sought to confirm a multi-factor model of Obsessive-compulsive personality disorder (OCPD) in a Hispanic outpatient sample and to explore associations of the OCPD factors with aggression, depression, and suicidal thoughts. One hundred and thirty monolingual, Spanish-speaking participants were recruited from a community mental health center and were assessed by bilingual doctoral-level clinicians. OCPD was highly prevalent (26%) in this sample. Multi-factor models of OCPD were tested and the two factors - perfectionism and interpersonal rigidity - provided the best model fit. Interpersonal rigidity was associated with aggression and anger while perfectionism was associated with depression and suicidal thoughts. (c) 2010 Elsevier Ltd. All rights reserved.

What mental health teams want in their leaders.

PubMed

Corrigan, P W; Garman, A N; Lam, C; Leary, M

1998-11-01

The authors present the findings of the first phase of a 3-year study developing a skills training curriculum for mental health team leaders. A factor model empirically generated from clinical team members was compared to Bass' (1990) Multifactor Model of Leadership. Members of mental health teams generated individual responses to questions about effective leaders. Results from this survey were subsequently administered to a sample of mental health team members. Analysis of these data yielded six factors: Autocratic Leadership, Clear Roles and Goals, Reluctant Leadership, Vision, Diversity Issues, and Supervision. Additional analyses suggest Bass' Multifactor Model offers a useful paradigm for developing a curriculum specific to the needs of mental health team leaders.

Probabilistic Methods for Structural Reliability and Risk

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2010-01-01

A probabilistic method is used to evaluate the structural reliability and risk of select metallic and composite structures. The method is a multiscale, multifunctional and it is based on the most elemental level. A multifactor interaction model is used to describe the material properties which are subsequently evaluated probabilistically. The metallic structure is a two rotor aircraft engine, while the composite structures consist of laminated plies (multiscale) and the properties of each ply are the multifunctional representation. The structural component is modeled by finite element. The solution method for structural responses is obtained by an updated simulation scheme. The results show that the risk for the two rotor engine is about 0.0001 and the composite built-up structure is also 0.0001.

Probabilistic Methods for Structural Reliability and Risk

NASA Technical Reports Server (NTRS)

Chamis, Christos C.

2008-01-01

A probabilistic method is used to evaluate the structural reliability and risk of select metallic and composite structures. The method is a multiscale, multifunctional and it is based on the most elemental level. A multi-factor interaction model is used to describe the material properties which are subsequently evaluated probabilistically. The metallic structure is a two rotor aircraft engine, while the composite structures consist of laminated plies (multiscale) and the properties of each ply are the multifunctional representation. The structural component is modeled by finite element. The solution method for structural responses is obtained by an updated simulation scheme. The results show that the risk for the two rotor engine is about 0.0001 and the composite built-up structure is also 0.0001.

Summarizing techniques that combine three non-parametric scores to detect disease-associated 2-way SNP-SNP interactions.

PubMed

Sengupta Chattopadhyay, Amrita; Hsiao, Ching-Lin; Chang, Chien Ching; Lian, Ie-Bin; Fann, Cathy S J

2014-01-01

Identifying susceptibility genes that influence complex diseases is extremely difficult because loci often influence the disease state through genetic interactions. Numerous approaches to detect disease-associated SNP-SNP interactions have been developed, but none consistently generates high-quality results under different disease scenarios. Using summarizing techniques to combine a number of existing methods may provide a solution to this problem. Here we used three popular non-parametric methods-Gini, absolute probability difference (APD), and entropy-to develop two novel summary scores, namely principle component score (PCS) and Z-sum score (ZSS), with which to predict disease-associated genetic interactions. We used a simulation study to compare performance of the non-parametric scores, the summary scores, the scaled-sum score (SSS; used in polymorphism interaction analysis (PIA)), and the multifactor dimensionality reduction (MDR). The non-parametric methods achieved high power, but no non-parametric method outperformed all others under a variety of epistatic scenarios. PCS and ZSS, however, outperformed MDR. PCS, ZSS and SSS displayed controlled type-I-errors (<0.05) compared to GS, APDS, ES (>0.05). A real data study using the genetic-analysis-workshop 16 (GAW 16) rheumatoid arthritis dataset identified a number of interesting SNP-SNP interactions. © 2013 Elsevier B.V. All rights reserved.

The emotional memory effect: differential processing or item distinctiveness?

PubMed

Schmidt, Stephen R; Saari, Bonnie

2007-12-01

A color-naming task was followed by incidental free recall to investigate how emotional words affect attention and memory. We compared taboo, nonthreatening negative-affect, and neutral words across three experiments. As compared with neutral words, taboo words led to longer color-naming times and better memory in both within- and between-subjects designs. Color naming of negative-emotion nontaboo words was slower than color naming of neutral words only during block presentation and at relatively short interstimulus intervals (ISIs). The nontaboo emotion words were remembered better than neutral words following blocked and random presentation and at both long and short ISIs, but only in mixed-list designs. Our results support multifactor theories of the effects of emotion on attention and memory. As compared with neutral words, threatening stimuli received increased attention, poststimulus elaboration, and benefit from item distinctiveness, whereas nonthreatening emotional stimuli benefited only from increased item distinctiveness.

Embracing interactions in ocean acidification research: confronting multiple stressor scenarios and context dependence

PubMed Central

Kordas, Rebecca L.; Harley, Christopher D. G.

2017-01-01

Changes in the Earth's environment are now sufficiently complex that our ability to forecast the emergent ecological consequences of ocean acidification (OA) is limited. Such projections are challenging because the effects of OA may be enhanced, reduced or even reversed by other environmental stressors or interactions among species. Despite an increasing emphasis on multifactor and multispecies studies in global change biology, our ability to forecast outcomes at higher levels of organization remains low. Much of our failure lies in a poor mechanistic understanding of nonlinear responses, a lack of specificity regarding the levels of organization at which interactions can arise, and an incomplete appreciation for linkages across these levels. To move forward, we need to fully embrace interactions. Mechanistic studies on physiological processes and individual performance in response to OA must be complemented by work on population and community dynamics. We must also increase our understanding of how linkages and feedback among multiple environmental stressors and levels of organization can generate nonlinear responses to OA. This will not be a simple undertaking, but advances are of the utmost importance as we attempt to mitigate the effects of ongoing global change. PMID:28356409

Embracing interactions in ocean acidification research: confronting multiple stressor scenarios and context dependence.

PubMed

Kroeker, Kristy J; Kordas, Rebecca L; Harley, Christopher D G

2017-03-01

Changes in the Earth's environment are now sufficiently complex that our ability to forecast the emergent ecological consequences of ocean acidification (OA) is limited. Such projections are challenging because the effects of OA may be enhanced, reduced or even reversed by other environmental stressors or interactions among species. Despite an increasing emphasis on multifactor and multispecies studies in global change biology, our ability to forecast outcomes at higher levels of organization remains low. Much of our failure lies in a poor mechanistic understanding of nonlinear responses, a lack of specificity regarding the levels of organization at which interactions can arise, and an incomplete appreciation for linkages across these levels. To move forward, we need to fully embrace interactions. Mechanistic studies on physiological processes and individual performance in response to OA must be complemented by work on population and community dynamics. We must also increase our understanding of how linkages and feedback among multiple environmental stressors and levels of organization can generate nonlinear responses to OA. This will not be a simple undertaking, but advances are of the utmost importance as we attempt to mitigate the effects of ongoing global change. © 2017 The Authors.

The challenge for genetic epidemiologists: how to analyze large numbers of SNPs in relation to complex diseases.

PubMed

Heidema, A Geert; Boer, Jolanda M A; Nagelkerke, Nico; Mariman, Edwin C M; van der A, Daphne L; Feskens, Edith J M

2006-04-21

Genetic epidemiologists have taken the challenge to identify genetic polymorphisms involved in the development of diseases. Many have collected data on large numbers of genetic markers but are not familiar with available methods to assess their association with complex diseases. Statistical methods have been developed for analyzing the relation between large numbers of genetic and environmental predictors to disease or disease-related variables in genetic association studies. In this commentary we discuss logistic regression analysis, neural networks, including the parameter decreasing method (PDM) and genetic programming optimized neural networks (GPNN) and several non-parametric methods, which include the set association approach, combinatorial partitioning method (CPM), restricted partitioning method (RPM), multifactor dimensionality reduction (MDR) method and the random forests approach. The relative strengths and weaknesses of these methods are highlighted. Logistic regression and neural networks can handle only a limited number of predictor variables, depending on the number of observations in the dataset. Therefore, they are less useful than the non-parametric methods to approach association studies with large numbers of predictor variables. GPNN on the other hand may be a useful approach to select and model important predictors, but its performance to select the important effects in the presence of large numbers of predictors needs to be examined. Both the set association approach and random forests approach are able to handle a large number of predictors and are useful in reducing these predictors to a subset of predictors with an important contribution to disease. The combinatorial methods give more insight in combination patterns for sets of genetic and/or environmental predictor variables that may be related to the outcome variable. As the non-parametric methods have different strengths and weaknesses we conclude that to approach genetic association studies using the case-control design, the application of a combination of several methods, including the set association approach, MDR and the random forests approach, will likely be a useful strategy to find the important genes and interaction patterns involved in complex diseases.

Multifactor Screener in OPEN: Scoring Procedures & Results

Cancer.gov

Scoring procedures were developed to convert a respondent's screener responses to estimates of individual dietary intake for percentage energy from fat, grams of fiber, and servings of fruits and vegetables.

Computational Simulation of the Formation and Material Behavior of Ice

NASA Technical Reports Server (NTRS)

Tong, Michael T.; Singhal, Surendra N.; Chamis, Christos C.

1994-01-01

Computational methods are described for simulating the formation and the material behavior of ice in prevailing transient environments. The methodology developed at the NASA Lewis Research Center was adopted. A three dimensional finite-element heat transfer analyzer was used to predict the thickness of ice formed under prevailing environmental conditions. A multi-factor interaction model for simulating the material behavior of time-variant ice layers is presented. The model, used in conjunction with laminated composite mechanics, updates the material properties of an ice block as its thickness increases with time. A sample case of ice formation in a body of water was used to demonstrate the methodology. The results showed that the formation and the material behavior of ice can be computationally simulated using the available composites technology.

Simulated Data for High Temperature Composite Design

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Abumeri, Galib H.

2006-01-01

The paper describes an effective formal method that can be used to simulate design properties for composites that is inclusive of all the effects that influence those properties. This effective simulation method is integrated computer codes that include composite micromechanics, composite macromechanics, laminate theory, structural analysis, and multi-factor interaction model. Demonstration of the method includes sample examples for static, thermal, and fracture reliability for a unidirectional metal matrix composite as well as rupture strength and fatigue strength for a high temperature super alloy. Typical results obtained for a unidirectional composite show that the thermal properties are more sensitive to internal local damage, the longitudinal properties degrade slowly with temperature, the transverse and shear properties degrade rapidly with temperature as do rupture strength and fatigue strength for super alloys.

A Computationally Efficient Hypothesis Testing Method for Epistasis Analysis using Multifactor Dimensionality Reduction

PubMed Central

Pattin, Kristine A.; White, Bill C.; Barney, Nate; Gui, Jiang; Nelson, Heather H.; Kelsey, Karl R.; Andrew, Angeline S.; Karagas, Margaret R.; Moore, Jason H.

2008-01-01

Multifactor dimensionality reduction (MDR) was developed as a nonparametric and model-free data mining method for detecting, characterizing, and interpreting epistasis in the absence of significant main effects in genetic and epidemiologic studies of complex traits such as disease susceptibility. The goal of MDR is to change the representation of the data using a constructive induction algorithm to make nonadditive interactions easier to detect using any classification method such as naïve Bayes or logistic regression. Traditionally, MDR constructed variables have been evaluated with a naïve Bayes classifier that is combined with 10-fold cross validation to obtain an estimate of predictive accuracy or generalizability of epistasis models. Traditionally, we have used permutation testing to statistically evaluate the significance of models obtained through MDR. The advantage of permutation testing is that it controls for false-positives due to multiple testing. The disadvantage is that permutation testing is computationally expensive. This is in an important issue that arises in the context of detecting epistasis on a genome-wide scale. The goal of the present study was to develop and evaluate several alternatives to large-scale permutation testing for assessing the statistical significance of MDR models. Using data simulated from 70 different epistasis models, we compared the power and type I error rate of MDR using a 1000-fold permutation test with hypothesis testing using an extreme value distribution (EVD). We find that this new hypothesis testing method provides a reasonable alternative to the computationally expensive 1000-fold permutation test and is 50 times faster. We then demonstrate this new method by applying it to a genetic epidemiology study of bladder cancer susceptibility that was previously analyzed using MDR and assessed using a 1000-fold permutation test. PMID:18671250

Leveraging Commercially Issued Multi-Factor Identification Credentials

NASA Technical Reports Server (NTRS)

Baldridge, Tim W.

2010-01-01

This slide presentation reviews the Identity, Credential and Access Management (ICAM) system. This system is a complete system of identity management, access to desktops and applications, use of smartcards, and building access throughout NASA.

Nonlinear, interacting responses to climate limit grassland production under global change.

PubMed

Zhu, Kai; Chiariello, Nona R; Tobeck, Todd; Fukami, Tadashi; Field, Christopher B

2016-09-20

Global changes in climate, atmospheric composition, and pollutants are altering ecosystems and the goods and services they provide. Among approaches for predicting ecosystem responses, long-term observations and manipulative experiments can be powerful approaches for resolving single-factor and interactive effects of global changes on key metrics such as net primary production (NPP). Here we combine both approaches, developing multidimensional response surfaces for NPP based on the longest-running, best-replicated, most-multifactor global-change experiment at the ecosystem scale-a 17-y study of California grassland exposed to full-factorial warming, added precipitation, elevated CO2, and nitrogen deposition. Single-factor and interactive effects were not time-dependent, enabling us to analyze each year as a separate realization of the experiment and extract NPP as a continuous function of global-change factors. We found a ridge-shaped response surface in which NPP is humped (unimodal) in response to temperature and precipitation when CO2 and nitrogen are ambient, with peak NPP rising under elevated CO2 or nitrogen but also shifting to lower temperatures. Our results suggest that future climate change will push this ecosystem away from conditions that maximize NPP, but with large year-to-year variability.

An omnibus permutation test on ensembles of two-locus analyses can detect pure epistasis and genetic heterogeneity in genome-wide association studies.

PubMed

Setsirichok, Damrongrit; Tienboon, Phuwadej; Jaroonruang, Nattapong; Kittichaijaroen, Somkit; Wongseree, Waranyu; Piroonratana, Theera; Usavanarong, Touchpong; Limwongse, Chanin; Aporntewan, Chatchawit; Phadoongsidhi, Marong; Chaiyaratana, Nachol

2013-01-01

This article presents the ability of an omnibus permutation test on ensembles of two-locus analyses (2LOmb) to detect pure epistasis in the presence of genetic heterogeneity. The performance of 2LOmb is evaluated in various simulation scenarios covering two independent causes of complex disease where each cause is governed by a purely epistatic interaction. Different scenarios are set up by varying the number of available single nucleotide polymorphisms (SNPs) in data, number of causative SNPs and ratio of case samples from two affected groups. The simulation results indicate that 2LOmb outperforms multifactor dimensionality reduction (MDR) and random forest (RF) techniques in terms of a low number of output SNPs and a high number of correctly-identified causative SNPs. Moreover, 2LOmb is capable of identifying the number of independent interactions in tractable computational time and can be used in genome-wide association studies. 2LOmb is subsequently applied to a type 1 diabetes mellitus (T1D) data set, which is collected from a UK population by the Wellcome Trust Case Control Consortium (WTCCC). After screening for SNPs that locate within or near genes and exhibit no marginal single-locus effects, the T1D data set is reduced to 95,991 SNPs from 12,146 genes. The 2LOmb search in the reduced T1D data set reveals that 12 SNPs, which can be divided into two independent sets, are associated with the disease. The first SNP set consists of three SNPs from MUC21 (mucin 21, cell surface associated), three SNPs from MUC22 (mucin 22), two SNPs from PSORS1C1 (psoriasis susceptibility 1 candidate 1) and one SNP from TCF19 (transcription factor 19). A four-locus interaction between these four genes is also detected. The second SNP set consists of three SNPs from ATAD1 (ATPase family, AAA domain containing 1). Overall, the findings indicate the detection of pure epistasis in the presence of genetic heterogeneity and provide an alternative explanation for the aetiology of T1D in the UK population.

The interaction of combined effects of the BDNF and PRKCG genes and negative life events in major depressive disorder.

PubMed

Yang, Chunxia; Sun, Ning; Liu, Zhifen; Li, Xinrong; Xu, Yong; Zhang, Kerang

2016-03-30

Major depressive disorder (MDD) is a mental disorder that results from complex interplay between multiple and partially overlapping sets of susceptibility genes and environmental factors. The brain derived neurotrophic factor (BDNF) and Protein kinase C gamma type (PRKCG) are logical candidate genes in MDD. Among diverse environmental factors, negative life events have been suggested to exert a crucial impact on brain development. In the present study, we hypothesized that interactions between genetic variants in BDNF and PRKCG and negative life events may play an important role in the development of MDD. We recruited a total of 406 patients with MDD and 391 age- and gender-matched control subjects. Gene-environment interactions were analyzed using generalized multifactor dimensionality reduction (GMDR). Under a dominant model, we observed a significant three-way interaction among BDNF rs6265, PRKCG rs3745406, and negative life events. The gene-environment combination of PRKCG rs3745406 C allele, BDNF rs6265 G allele and high level of negative life events (C-G-HN) was significantly associated with MDD (OR, 5.97; 95% CI, 2.71-13.15). To our knowledge, this is the first report of evidence that the BDNF-PRKCG interaction may modify the relationship between negative life events and MDD in the Chinese population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An overview of a multifactor-system theory of personality and individual differences: III. Life span development and the heredity-environment issue.

PubMed

Powell, A; Royce, J R

1981-12-01

In Part III of this three-part series on multifactor-system theory, multivariate, life-span development is approached from the standpoint of a quantitative and qualitative analysis of the ontogenesis of factors in each of the six systems. The pattern of quantitative development (described via the Gompertz equation and three developmental parameters) involves growth, stability, and decline, and qualitative development involves changes in the organization of factors (e.g., factor differentiation and convergence). Hereditary and environmental sources of variation are analyzed via the factor gene model and the concept of heredity-dominant factors, and the factor-learning model and environment-dominant factors. It is hypothesized that the sensory and motor systems are heredity dominant, that the style and value systems are environment dominant, and that the cognitive and affective systems are partially heredity dominant.

Management of suicidal and self-harming behaviors in prisons: systematic literature review of evidence-based activities.

PubMed

Barker, Emma; Kõlves, Kairi; De Leo, Diego

2014-01-01

The purpose of this study was to systematically analyze existing literature testing the effectiveness of programs involving the management of suicidal and self-harming behaviors in prisons. For the study, 545 English-language articles published in peer reviewed journals were retrieved using the terms "suicid*," "prevent*," "prison," or "correctional facility" in SCOPUS, MEDLINE, PROQUEST, and Web of Knowledge. In total, 12 articles were relevant, with 6 involving multi-factored suicide prevention programs, and 2 involving peer focused programs. Others included changes to the referral and care of suicidal inmates, staff training, legislation changes, and a suicide prevention program for inmates with Borderline Personality Disorder. Multi-factored suicide prevention programs appear most effective in the prison environment. Using trained inmates to provide social support to suicidal inmates is promising. Staff attitudes toward training programs were generally positive.

Entropy measure of credit risk in highly correlated markets

NASA Astrophysics Data System (ADS)

Gottschalk, Sylvia

2017-07-01

We compare the single and multi-factor structural models of corporate default by calculating the Jeffreys-Kullback-Leibler divergence between their predicted default probabilities when asset correlations are either high or low. Single-factor structural models assume that the stochastic process driving the value of a firm is independent of that of other companies. A multi-factor structural model, on the contrary, is built on the assumption that a single firm's value follows a stochastic process correlated with that of other companies. Our main results show that the divergence between the two models increases in highly correlated, volatile, and large markets, but that it is closer to zero in small markets, when asset correlations are low and firms are highly leveraged. These findings suggest that during periods of financial instability, when asset volatility and correlations increase, one of the models misreports actual default risk.

Application of the multifactor dimensionality reduction method in evaluation of the roles of multiple genes/enzymes in multidrug-resistant acquisition in Pseudomonas aeruginosa strains.

PubMed

Yao, Z; Peng, Y; Bi, J; Xie, C; Chen, X; Li, Y; Ye, X; Zhou, J

2016-03-01

Multidrug-resistant Pseudomonas aeruginosa (MDRPA) infections are major threats to healthcare-associated infection control and the intrinsic molecular mechanisms of MDRPA are also unclear. We examined 348 isolates of P. aeruginosa, including 188 MDRPA and 160 non-MDRPA, obtained from five tertiary-care hospitals in Guangzhou, China. Significant correlations were found between gene/enzyme carriage and increased rates of antimicrobial resistance (P < 0·01). gyrA mutation, OprD loss and metallo-β-lactamase (MBL) presence were identified as crucial molecular risk factors for MDRPA acquisition by a combination of univariate logistic regression and a multifactor dimensionality reduction approach. The MDRPA rate was also elevated with the increase in positive numbers of those three determinants (P < 0·001). Thus, gyrA mutation, OprD loss and MBL presence may serve as predictors for early screening of MDRPA infections in clinical settings.

The Research on Tunnel Surrounding Rock Classification Based on Geological Radar and Probability Theory

NASA Astrophysics Data System (ADS)

Xiao Yong, Zhao; Xin, Ji Yong; Shuang Ying, Zuo

2018-03-01

In order to effectively classify the surrounding rock types of tunnels, a multi-factor tunnel surrounding rock classification method based on GPR and probability theory is proposed. Geological radar was used to identify the geology of the surrounding rock in front of the face and to evaluate the quality of the rock face. According to the previous survey data, the rock uniaxial compressive strength, integrity index, fissure and groundwater were selected for classification. The related theories combine them into a multi-factor classification method, and divide the surrounding rocks according to the great probability. Using this method to classify the surrounding rock of the Ma’anshan tunnel, the surrounding rock types obtained are basically the same as those of the actual surrounding rock, which proves that this method is a simple, efficient and practical rock classification method, which can be used for tunnel construction.

Spectroscopically Enhanced Method and System for Multi-Factor Biometric Authentication

NASA Astrophysics Data System (ADS)

Pishva, Davar

This paper proposes a spectroscopic method and system for preventing spoofing of biometric authentication. One of its focus is to enhance biometrics authentication with a spectroscopic method in a multifactor manner such that a person's unique ‘spectral signatures’ or ‘spectral factors’ are recorded and compared in addition to a non-spectroscopic biometric signature to reduce the likelihood of imposter getting authenticated. By using the ‘spectral factors’ extracted from reflectance spectra of real fingers and employing cluster analysis, it shows how the authentic fingerprint image presented by a real finger can be distinguished from an authentic fingerprint image embossed on an artificial finger, or molded on a fingertip cover worn by an imposter. This paper also shows how to augment two widely used biometrics systems (fingerprint and iris recognition devices) with spectral biometrics capabilities in a practical manner and without creating much overhead or inconveniencing their users.

Transformational, transactional, and passive-avoidant leadership characteristics of a surgical resident cohort: analysis using the multifactor leadership questionnaire and implications for improving surgical education curriculums.

PubMed

Horwitz, Irwin B; Horwitz, Sujin K; Daram, Pallavi; Brandt, Mary L; Brunicardi, F Charles; Awad, Samir S

2008-07-01

The need for leadership training has become recognized as being highly important to improving medical care, and should be included in surgical resident education curriculums. Surgical residents (n = 65) completed the 5x-short version of the Multifactor Leadership Questionnaire as a means of identifying leadership areas most in need of training among medical residents. The leadership styles of the residents were measured on 12 leadership scales. Comparisons between gender and postgraduate year (PGY) and comparisons to national norms were conducted. Of 12 leadership scales, the residents as a whole had significantly higher management by exception active and passive scores than those of the national norm (t = 6.6, P < 0.01, t = 2.8, P < 0.01, respectively), and significantly lower individualized consideration scores than the norm (t = 2.7, P < 0.01). Only one score, management by exception active was statistically different and higher among males than females (t = 2.12, P < 0.05). PGY3-5 had significantly lower laissez-faire scores than PGY1-2 (t = 2.20, P < 0.05). Principal component analysis revealed two leadership factors with eigenvalues over 1.0. Hierarchical regression found evidence of an augmentation effect for transformational leadership. Areas of resident leadership strengths and weaknesses were identified. The Multifactor Leadership Questionnaire was demonstrated to be a valuable tool for identifying specific areas where leadership training would be most beneficial in the educational curriculum. The future use of this instrument could prove valuable to surgical education training programs.

Development and validation of a multifactor mindfulness scale in youth: The Comprehensive Inventory of Mindfulness Experiences-Adolescents (CHIME-A).

PubMed

Johnson, Catherine; Burke, Christine; Brinkman, Sally; Wade, Tracey

2017-03-01

Mindfulness-based interventions show consistent benefits in adults for a range of pathologies, but exploration of these approaches in youth is an emergent field, with limited measures of mindfulness for this population. This study aimed to investigate whether multifactor scales of mindfulness can be used in adolescents. A series of studies are presented assessing the performance of a recently developed adult measure, the Comprehensive Inventory of Mindfulness Experiences (CHIME) in 4 early adolescent samples. Study 1 was an investigation of how well the full adult measure (37 items) was understood by youth (N = 292). Study 2 piloted a revision of items in child friendly language with a small group (N = 48). The refined questionnaire for adolescents (CHIME-A) was then tested in Study 3 in a larger sample (N = 461) and subjected to exploratory factor analysis and a range of external validity measures. Study 4 was a confirmatory factor analysis in a new sample (N = 498) with additional external validity measures. Study 5 tested temporal stability (N = 120). Results supported an 8-factor 25-item measure of mindfulness in adolescents, with excellent model fit indices and sound internal consistency for the 8 subscales. Although the CFA supported an overarching factor, internal reliability of a combined total score was poor. The development of a multifactor measure represents a first step toward testing developmental models of mindfulness in young people. This in turn will aid construction of evidence based interventions that are not simply downward derivations of adult mindfulness programs. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Confounding Problems in Multifactor AOV When Using Several Organismic Variables of Limited Reliability

ERIC Educational Resources Information Center

Games, Paul A.

1975-01-01

A brief introduction is presented on how multiple regression and linear model techniques can handle data analysis situations that most educators and psychologists think of as appropriate for analysis of variance. (Author/BJG)

Gene-environment interaction between adiponectin gene polymorphisms and environmental factors on the risk of diabetic retinopathy.

PubMed

Li, Yuan; Wu, Qun Hong; Jiao, Ming Li; Fan, Xiao Hong; Hu, Quan; Hao, Yan Hua; Liu, Ruo Hong; Zhang, Wei; Cui, Yu; Han, Li Yuan

2015-01-01

To evaluate whether the adiponectin gene is associated with diabetic retinopathy (DR) risk and interaction with environmental factors modifies the DR risk, and to investigate the relationship between serum adiponectin levels and DR. Four adiponectin polymorphisms were evaluated in 372 DR cases and 145 controls. Differences in environmental factors between cases and controls were evaluated by unconditional logistic regression analysis. The model-free multifactor dimensionality reduction method and traditional multiple regression models were applied to explore interactions between the polymorphisms and environmental factors. Using the Bonferroni method, we found no significant associations between four adiponectin polymorphisms and DR susceptibility. Multivariate logistic regression found that physical activity played a protective role in the progress of DR, whereas family history of diabetes (odds ratio 1.75) and insulin therapy (odds ratio 1.78) were associated with an increased risk for DR. The interaction between the C-11377 G (rs266729) polymorphism and insulin therapy might be associated with DR risk. Family history of diabetes combined with insulin therapy also increased the risk of DR. No adiponectin gene polymorphisms influenced the serum adiponectin levels. Serum adiponectin levels did not differ between the DR group and non-DR group. No significant association was identified between four adiponectin polymorphisms and DR susceptibility after stringent Bonferroni correction. The interaction between C-11377G (rs266729) polymorphism and insulin therapy, as well as the interaction between family history of diabetes and insulin therapy, might be associated with DR susceptibility.

Connecting to HPC Systems | High-Performance Computing | NREL

Science.gov Websites

one of the following methods, which use multi-factor authentication. First, you will need to set up If you just need access to a command line on an HPC system, use one of the following methods

Combined bending and thermal fatigue of high-temperature metal-matrix composites - Computational simulation

NASA Technical Reports Server (NTRS)

Gotsis, Pascal K.; Chamis, Christos C.

1992-01-01

The nonlinear behavior of a high-temperature metal-matrix composite (HT-MMC) was simulated by using the metal matrix composite analyzer (METCAN) computer code. The simulation started with the fabrication process, proceeded to thermomechanical cyclic loading, and ended with the application of a monotonic load. Classical laminate theory and composite micromechanics and macromechanics are used in METCAN, along with a multifactor interaction model for the constituents behavior. The simulation of the stress-strain behavior from the macromechanical and the micromechanical points of view, as well as the initiation and final failure of the constituents and the plies in the composite, were examined in detail. It was shown that, when the fibers and the matrix were perfectly bonded, the fracture started in the matrix and then propagated with increasing load to the fibers. After the fibers fractured, the composite lost its capacity to carry additional load and fractured.

Probabilistic Structural Analysis Methods (PSAM) for select space propulsion system components, part 2

NASA Technical Reports Server (NTRS)

1991-01-01

The technical effort and computer code enhancements performed during the sixth year of the Probabilistic Structural Analysis Methods program are summarized. Various capabilities are described to probabilistically combine structural response and structural resistance to compute component reliability. A library of structural resistance models is implemented in the Numerical Evaluations of Stochastic Structures Under Stress (NESSUS) code that included fatigue, fracture, creep, multi-factor interaction, and other important effects. In addition, a user interface was developed for user-defined resistance models. An accurate and efficient reliability method was developed and was successfully implemented in the NESSUS code to compute component reliability based on user-selected response and resistance models. A risk module was developed to compute component risk with respect to cost, performance, or user-defined criteria. The new component risk assessment capabilities were validated and demonstrated using several examples. Various supporting methodologies were also developed in support of component risk assessment.

The Problem of Dualism in Modern Western Medicine

PubMed Central

Gendle, Mathew H.

2016-01-01

Dualism is historically important in that it allowed the medical practice to be divorced from church oversight. The reductionist approaches of modern Western medicine facilitate a dispassionate and mechanistic approach to patient care, and dualist views promoted by complementary and alternative medicine are also problematic. Behavioural disorders are multifactorally realizable and emerge apparently chaotically from interactions between internal physiological systems and the patient's environment and experiential history. Conceptualizations of behavioural disorders that are based on dualism deny the primacy of individual physiology in the generation of pathology and distract from therapies that are most likely to produce positive outcomes. Behavioural health professionals should adopt holistic models of patient care, but these models must be based on methodologies that emphasize radical emergence over the artificial separation of the “physical” and “mental.” This will allow for the humanistic practice of medicine while simultaneously maximizing the likelihood of treatment success. PMID:28031628

Combined thermal and bending fatigue of high-temperature metal-matrix composites: Computational simulation

NASA Technical Reports Server (NTRS)

Gotsis, Pascal K.

1991-01-01

The nonlinear behavior of a high-temperature metal-matrix composite (HT-MMC) was simulated by using the metal matrix composite analyzer (METCAN) computer code. The simulation started with the fabrication process, proceeded to thermomechanical cyclic loading, and ended with the application of a monotonic load. Classical laminate theory and composite micromechanics and macromechanics are used in METCAN, along with a multifactor interaction model for the constituents behavior. The simulation of the stress-strain behavior from the macromechanical and the micromechanical points of view, as well as the initiation and final failure of the constituents and the plies in the composite, were examined in detail. It was shown that, when the fibers and the matrix were perfectly bonded, the fracture started in the matrix and then propagated with increasing load to the fibers. After the fibers fractured, the composite lost its capacity to carry additional load and fractured.

The relationship between glucocorticoid receptor polymorphisms, stressful life events, social support, and post-traumatic stress disorder.

PubMed

Lian, Yulong; Xiao, Jing; Wang, Qian; Ning, Li; Guan, Suzhen; Ge, Hua; Li, Fuye; Liu, Jiwen

2014-08-12

It is debatable whether or not glucocorticoid receptor (GR) polymorphisms moderate susceptibility to PTSD. Our objective was to examine the effects of stressful life events, social support, GR genotypes, and gene-environment interactions on the etiology of PTSD. Three tag single nucleotide polymorphisms, trauma events, stressful life events, and social support were assessed in 460 patients with PTSD and 1158 control subjects from a Chinese Han population. Gene-environment interactions were analyzed by generalized multifactor dimensionality reduction (GMDR). Variation in GR at rs41423247 and rs258747, stressful life events, social support, and the number of traumatic events were each separately associated with the risk for PTSD. A gene-environment interaction among the polymorphisms, rs41423247 and rs258747, the number of traumatic events, stressful life events, and social support resulted in an increased risk for PTSD. High-risk individuals (a large number of traumatic events, G allele of rs258747 and rs41423247, high level stressful life events, and low social support) had a 3.26-fold increased risk of developing PTSD compared to low-risk individuals. The association was statistically significant in the sub-groups with and without childhood trauma. Our data support the notion that stressful life events, the number of trauma events, and social support may play a contributing role in the risk for PTSD by interacting with GR gene polymorphisms.

Outdoor Leaders' Emotional Intelligence and Transformational Leadership

ERIC Educational Resources Information Center

Hayashi, Aya; Ewert, Alan

2006-01-01

This study explored the concept of outdoor leadership from the perspectives of emotional intelligence and transformational leadership. Levels of emotional intelligence, multifactor leadership, outdoor experience, and social desirability were examined using 46 individuals designated as outdoor leaders. The results revealed a number of unique…

75 FR 67776 - Comment Request; Review of Productivity Statistics

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-03

... DEPARTMENT OF LABOR Bureau of Labor Statistics Comment Request; Review of Productivity Statistics... Statistics (BLS) is responsible for publishing measures of labor productivity and multifactor productivity..., Office of Productivity and Technology, Bureau of Labor Statistics, Room 2150, 2 Massachusetts Avenue, NE...

Personality Characteristics, Job Stressors, and Job Satisfaction: Main and Interaction Effects on Psychological and Physical Health Conditions of Italian Schoolteachers.

PubMed

Zurlo, Maria Clelia; Pes, Daniela; Capasso, Roberto

2016-08-01

The study proposed an application of the transactional model of stress in teaching elaborated by Travers and Cooper in 1996, and aimed to investigate the influence of personality characteristics (coping strategies, type A behaviors), situational characteristics (sources of pressure), and perceived job satisfaction in the prediction of teachers' psychophysical health conditions. The Italian version of the Teacher Stress Questionnaire was administered to 621 teachers. Logistic regression was used to evaluate significant main and interaction effects of personality characteristics, situational characteristics, and perceived job satisfaction on teachers' self-reported psychophysical health conditions. The findings highlighted specific coping strategies (focused on the problem, on innovation, and on hobbies and pastimes) and dimensions of job satisfaction (related to intrinsic aspects of job and to employee relations) buffering the negative effects of several job stressors. Type A behaviors and coping strategies focused on mobilized social support, suppression of stress, and not confronting the situation had main and interactions with negative effects on psychophysical health. Findings confirmed the necessity to run multi-factor research to analyze the different combinations of individual and situational variables implicated in negative health outcomes and to highlight the most significant buffering or increasing associations. © The Author(s) 2016.

A flexible computational framework for detecting, characterizing, and interpreting statistical patterns of epistasis in genetic studies of human disease susceptibility.

PubMed

Moore, Jason H; Gilbert, Joshua C; Tsai, Chia-Ti; Chiang, Fu-Tien; Holden, Todd; Barney, Nate; White, Bill C

2006-07-21

Detecting, characterizing, and interpreting gene-gene interactions or epistasis in studies of human disease susceptibility is both a mathematical and a computational challenge. To address this problem, we have previously developed a multifactor dimensionality reduction (MDR) method for collapsing high-dimensional genetic data into a single dimension (i.e. constructive induction) thus permitting interactions to be detected in relatively small sample sizes. In this paper, we describe a comprehensive and flexible framework for detecting and interpreting gene-gene interactions that utilizes advances in information theory for selecting interesting single-nucleotide polymorphisms (SNPs), MDR for constructive induction, machine learning methods for classification, and finally graphical models for interpretation. We illustrate the usefulness of this strategy using artificial datasets simulated from several different two-locus and three-locus epistasis models. We show that the accuracy, sensitivity, specificity, and precision of a naïve Bayes classifier are significantly improved when SNPs are selected based on their information gain (i.e. class entropy removed) and reduced to a single attribute using MDR. We then apply this strategy to detecting, characterizing, and interpreting epistatic models in a genetic study (n = 500) of atrial fibrillation and show that both classification and model interpretation are significantly improved.

A case-control study of rheumatoid arthritis revealed abdominal obesity and environmental risk factor interactions in northern China.

PubMed

Fu, Lingyu; Zhang, Jianming; Jin, Lei; Zhang, Yao; Cui, Saisai; Chen, Meng

2018-03-01

The aim of this study was to evaluate new and previously hypothesized environmental risk factors and their interaction with rheumatoid arthritis (RA). Four hundred patients recently diagnosed with RA and 400 controls frequency-matched by gender and birth year using Propensity Score Matching (PSM) were selected from northern China. Investigation was performed using self-reported data from interviewer-administered surveys. Associations between exposure variables and risk of RA were evaluated using multifactor non-conditional logistic regression. It showed that damp localities, draft indoor, abdominal obesity (AO), and family history of RA among first-degree relatives were independent risk factors and drinking of milk was independent protective factors for RA. Besides these risk factors, in women, infrequent delivery times, early age at menopause, and late age at menarche were also independent risk factors for RA. Both the additive model and the multiplication model suggested that there was an interaction relationship between AO and damp localities (p < .001), and only the additive model suggested that there was interaction relationship between AO and no milk drinking (p < .001) in our study population. In women, there was interaction relationship between AO and damp localities (p < .001) and between AO and age at menopause (p < .001). In northern China, damp localities, draft indoor, AO, family history of RA among first-degree relatives, and no milk drinking may be important risk factors of RA patients.

Herbivory enhances the resistance of mangrove forest to cordgrass invasion.

PubMed

Zhang, Yihui; Meng, Hanyu; Wang, Yi; He, Qiang

2018-06-01

The biotic resistance hypothesis proposes that biotic interactions, such as competition and herbivory, resist the establishment and spread of non-native species. The relative and interactive role of competition and herbivory in resisting plant invasions, however, remains poorly understood. We investigated the interactive role of competition and herbivory (by the native rodent Rattus losea) in resisting Spartina alterniflora (cordgrass) invasions into mangrove forests. In southern China, although exotic cordgrass numerically dominates intertidal mudflats and open gaps in mangrove forests, intact forests appear to be highly resistant to cordgrass invasion. A field transplant and rodent exclusion experiment showed that while the impact of rodent grazing on cordgrass was weak on mangrove forest edges and open mudflats, rodent grazing strongly suppressed cordgrass in mangrove understory habitats. A greenhouse experiment confirmed a synergistic interaction between grazing and light availability (a proxy for mangrove shading and light competition) in suppressing cordgrass establishment, with the strongest impacts of grazing in low light conditions that likely weakened cordgrass to survive and resprout. When both were present, as in mangrove understory habitats, grazing and low light acted in concert to eliminate cordgrass establishment, resulting in resistance of mangrove forests to cordgrass invasion. Our results reveal that grazing by native herbivores can enhance the resistance of mangrove forests to cordgrass invasion in southern China, and suggest that investigating multifactor interactions may be critical to understanding community resistance to exotic invasions. © 2018 by the Ecological Society of America.

You Have What? Personality! Traits That Predict Leadership Styles for Elementary Administrators

ERIC Educational Resources Information Center

Garcia, Melinda

2013-01-01

This research explored relationships between followers' perceptions of elementary school principals' Big Five Personality Traits, using the "International Personality Item Pool" (IPIP) (Goldberg, 1999), and principals' Leadership Styles, using the "Multi-factor Leadership Questionnaire" (MLQ) (Bass & Avolio, 2004). A sample…

Understanding the Supplemental Instruction Leader

ERIC Educational Resources Information Center

James, Adrian; Moore, Lori

2018-01-01

This article explored the learning styles and leadership styles of Supplemental Instruction (SI) leaders at Texas A&M University, and the impact of those preferences on recurring attendance to their sessions. The Learning Style Inventory, the Multifactor Leadership Questionnaire, and a demographic instrument were administered to SI leaders…

Factorial Design: An Eight Factor Experiment Using Paper Helicopters

NASA Technical Reports Server (NTRS)

Kozma, Michael

1996-01-01

The goal of this paper is to present the analysis of the multi-factor experiment (factorial design) conducted in EG490, Junior Design at Loyola College in Maryland. The discussion of this paper concludes the experimental analysis and ties the individual class papers together.

The Multiple Component Alternative for Gifted Education.

ERIC Educational Resources Information Center

Swassing, Ray

1984-01-01

The Multiple Component Model (MCM) of gifted education includes instruction which may overlap in literature, history, art, enrichment, languages, science, physics, math, music, and dance. The model rests on multifactored identification and requires systematic development and selection of components with ongoing feedback and evaluation. (CL)

Multilinear Graph Embedding: Representation and Regularization for Images.

PubMed

Chen, Yi-Lei; Hsu, Chiou-Ting

2014-02-01

Given a set of images, finding a compact and discriminative representation is still a big challenge especially when multiple latent factors are hidden in the way of data generation. To represent multifactor images, although multilinear models are widely used to parameterize the data, most methods are based on high-order singular value decomposition (HOSVD), which preserves global statistics but interprets local variations inadequately. To this end, we propose a novel method, called multilinear graph embedding (MGE), as well as its kernelization MKGE to leverage the manifold learning techniques into multilinear models. Our method theoretically links the linear, nonlinear, and multilinear dimensionality reduction. We also show that the supervised MGE encodes informative image priors for image regularization, provided that an image is represented as a high-order tensor. From our experiments on face and gait recognition, the superior performance demonstrates that MGE better represents multifactor images than classic methods, including HOSVD and its variants. In addition, the significant improvement in image (or tensor) completion validates the potential of MGE for image regularization.

A Study on the Assessment of Multi-Factors Affecting Urban Floods Using Satellite Image: A Case Study in Nakdong Basin, S. Korea

NASA Astrophysics Data System (ADS)

Kwak, Youngjoo; Kondoh, Akihiko

2010-05-01

Floods are also related to the changes in social economic conditions and land use. Recently, floods increased due to rapid urbanization and human activity in the lowland. Therefore, integrated management of total basin system is necessary to get the secure society. Typhoon ‘Rusa’ swept through eastern and southern parts of South Korea in the 2002. This pity experience gave us valuable knowledge that could be used to mitigate the future flood hazards. The purpose of this study is to construct the digital maps of the multi-factors related to urban flood concerning geomorphologic characteristics, land cover, and surface wetness. Parameters particularly consider geomorphologic functional unit, geomorphologic parameters derived from DEM (digital elevation model), and land use. The research area is Nakdong River Basin in S. Korea. As a result of preliminary analysis for Pusan area, the vulnerability map and the flood-prone areas can be extracted by applying spatial analysis on GIS (geographic information system).

Interaction among variants in the SLC gene family (SLC6A14, SLC26A9, SLC11A1, and SLC9A3) and CFTR mutations with clinical markers of cystic fibrosis.

PubMed

Pereira, Stephanie V N; Ribeiro, Jose D; Bertuzzo, Carmen S; Marson, Fernando A L

2018-04-10

Cystic fibrosis (CF) is due to dysfunction of the CFTR channel and function of this channel is, in turn, affected by modifier genes that can impact the clinical phenotype. In this context, we analyzed the interaction among rs3788766*SLC6A14, rs7512462*SLC26A9, rs17235416*SLC11A1, and rs17563161*SLC9A3 variants, CFTR mutations and 40 CF severity markers by the Multifactor Dimensionality Reduction (MDR) model. A total of 164 patients with CF were included in the study. The variants in the modifier genes were identified by real-time PCR and the genotype of the CFTR gene in the diagnostic routine. Analysis of interaction between variants, CFTR mutations groupings and demographic, clinical and laboratory data were performed by the MDR. There were interaction between the rs3788766, rs7512462, rs17235416, and rs17563161 variants, and CFTR mutations with pancreatic insufficiency (PI), onset of digestive symptoms, and presence of mucoid Pseudomonas aeruginosa. Regarding PI, the interaction was observed for CFTR*rs17563161 (P-value = 0.015). Also, for onset of digestive symptoms the interaction was observed for CFTR*rs3788766*rs7512462*rs17235416*rs17563161 (P-value = 0.036). Considering the presence of mucoid P. aeruginosa, the interaction occurred for CFTR*rs3788766*rs7512462*rs17563161 (P-value = 0.035). Interaction between variants in the SLC family genes and the grouping for CFTR mutations were associated with PI, onset of digestive symptoms and mucoid P. aeruginosa, being important to determine one of the factors that may cause the diversity among the patients with CF. © 2018 Wiley Periodicals, Inc.

Usable Multi-factor Authentication and Risk-based Authorization

DTIC Science & Technology

2015-06-01

acceptance. In the previous section we described user studies that explored risks perceived by individuals using online banking and credit card purchases... iTunes purchases. We note that the fingerprint scanners in the current experiment are very different from what would be available in future. However

Exploring the Relationships between Principals' Life Experiences and Transformational Leadership Behaviours

ERIC Educational Resources Information Center

Nash, Steve; Bangert, Art

2014-01-01

The primary objective of this research study was to explore the relationships between principals' life experiences and their transformational leadership behaviours. Over 212 public school principals completed both the lifetime leadership inventory (LLI) and the multifactor leadership questionnaire (MLQ). Exploratory and confirmatory factor…

Obesity, hypertension and genetic variation in the TIGER Study

USDA-ARS?s Scientific Manuscript database

Obesity and hypertension are multifactoral conditions in which the onset and severity of the conditions are influenced by the interplay of genetic and environmental factors. We hypothesize that multiple genes and environmental factors account for a significant amount of variation in BMI and blood pr...

Emotional Intelligence and the Career Choice Process.

ERIC Educational Resources Information Center

Emmerling, Robert J.; Cherniss, Cary

2003-01-01

Emotional intelligence as conceptualized by Mayer and Salovey consists of perceiving emotions, using emotions to facilitate thoughts, understanding emotions, and managing emotions to enhance personal growth. The Multifactor Emotional Intelligence Scale has proven a valid and reliable measure that can be used to explore the implications of…

Is there a genetic solution to bovine respiratory disease complex?

USDA-ARS?s Scientific Manuscript database

Bovine respiratory disease complex (BRDC) is a complex multi-factor disease, which increases costs and reduces revenue from feedlot cattle. Multiple stressors and pathogens (viral and bacterial) have been implicated in the etiology of BRDC, therefore multiple approaches will be needed to evaluate a...

CMDR based differential evolution identifies the epistatic interaction in genome-wide association studies.

PubMed

Yang, Cheng-Hong; Chuang, Li-Yeh; Lin, Yu-Da

2017-08-01

Detecting epistatic interactions in genome-wide association studies (GWAS) is a computational challenge. Such huge numbers of single-nucleotide polymorphism (SNP) combinations limit the some of the powerful algorithms to be applied to detect the potential epistasis in large-scale SNP datasets. We propose a new algorithm which combines the differential evolution (DE) algorithm with a classification based multifactor-dimensionality reduction (CMDR), termed DECMDR. DECMDR uses the CMDR as a fitness measure to evaluate values of solutions in DE process for scanning the potential statistical epistasis in GWAS. The results indicated that DECMDR outperforms the existing algorithms in terms of detection success rate by the large simulation and real data obtained from the Wellcome Trust Case Control Consortium. For running time comparison, DECMDR can efficient to apply the CMDR to detect the significant association between cases and controls amongst all possible SNP combinations in GWAS. DECMDR is freely available at https://goo.gl/p9sLuJ . chuang@isu.edu.tw or e0955767257@yahoo.com.tw. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Occupational therapy practitioners' perceptions of rehabilitation managers' leadership styles and the outcomes of leadership.

PubMed

Jeff, Snodgrass; Douthitt, Shannon; Ellis, Rachel; Wade, Shelly; Plemons, Josh

2008-01-01

The purpose of this research was to serve as a pilot study to investigate the association between occupational therapy practitioners' perceptions of rehabilitation managers' leadership styles and the outcomes of leadership. Data for this study were collected using the Multifactor Leadership Questionnaire Form 5X and a self-designed demographic questionnaire. The study working sample included 73 occupational therapy practitioners. Major findings from the study indicate that overall, transformational, and transactional leadership styles are associated with leadership outcomes. Transformational leadership had a significant (p < 0.01) positive association with the leadership outcomes, whereas transactional leadership had a significant (p < 0.01) negative association with the leadership outcomes. The contingent reward leadership attribute (although belonging to the transactional leadership construct) was found to be positively associated with leadership outcomes, similar to the transformational leadership constructs. The results of this research suggest that transformational leadership styles have a positive association with leadership outcomes, whereas transactional leadership styles have a negative association, excluding the positive transactional contingent reward attribute. A larger, random sample is recommended as a follow-up study.

Examining Dimensions of Self-Efficacy for Writing

ERIC Educational Resources Information Center

Bruning, Roger; Dempsey, Michael; Kauffman, Douglas F.; McKim, Courtney; Zumbrunn, Sharon

2013-01-01

A multifactor perspective on writing self-efficacy was examined in 2 studies. Three factors were proposed--self-efficacy for writing ideation, writing conventions, and writing self-regulation--and a scale constructed to reflect these factors. In Study 1, middle school students (N = 697) completed the Self-Efficacy for Writing Scale (SEWS), along…

Do Leadership Styles Influence Organizational Health? A Study in Educational Organizations

ERIC Educational Resources Information Center

Toprak, Mustafa; Inandi, Bulent; Colak, Ahmet Levent

2015-01-01

This research aims to investigate the effect of leadership styles of school principals on organizational health. Causal-comparative research model was used to analyze the relationships between leadership types and organizational health. For data collection, a Likert type Multifactor Leadership scale questionnaire and Organizational Health scale…

Transformational Leadership and the Leadership Performance of Oregon Secondary School Principals

ERIC Educational Resources Information Center

Breaker, Jason Lee

2009-01-01

A study of 118 secondary school principals in Oregon was conducted to examine the relationship of transformational leadership to secondary school principals' leadership performance. This study measured the transformational leadership of secondary school principals in Oregon using the "Multifactor Leadership Questionnaire (5X-Short)"…

Appropriate Use Policy | High-Performance Computing | NREL

Science.gov Websites

users of the National Renewable Energy Laboratory (NREL) High Performance Computing (HPC) resources government agency, National Laboratory, University, or private entity, the intellectual property terms (if issued a multifactor token which may be a physical token or a virtual token used with one-time password

The Negative Testing Effect and Multifactor Account

ERIC Educational Resources Information Center

Peterson, Daniel J.; Mulligan, Neil W.

2013-01-01

Across 3 experiments, we investigated the factors that dictate when taking a test improves subsequent memory performance (the "testing effect"). In Experiment 1, participants retrieving a set of targets during a retrieval practice phase ultimately recalled fewer of those targets compared with a group of participants who studied the…

Worker Traits Training Unit. MA Handbook No. 314.

ERIC Educational Resources Information Center

Manpower Administration (DOL), Washington, DC.

This training unit provides persons involved in employment interviewing, vocational counseling, curriculum planning, and other manpower activities with a multifactor approach for obtaining information from an individual and relating the data to job requirements. It is intended to result in the development of the bridge between client potential and…

Organizational Deviance and Multi-Factor Leadership

ERIC Educational Resources Information Center

Aksu, Ali

2016-01-01

Organizational deviant behaviors can be defined as behaviors that have deviated from standards and uncongenial to organization's expectations. When such behaviors have been thought to damage the organization, it can be said that reducing the deviation behaviors at minimum level is necessary for a healthy organization. The aim of this research is…

A Multifactor Approach to Research in Instructional Technology.

ERIC Educational Resources Information Center

Ragan, Tillman J.

In a field such as instructional design, explanations of educational outcomes must necessarily consider multiple input variables. To adequately understand the contribution made by the independent variables, it is helpful to have a visual conception of how the input variables interrelate. Two variable models are adequately represented by a two…

Gene-gene interactions and gene polymorphisms of VEGFA and EG-VEGF gene systems in recurrent pregnancy loss.

PubMed

Su, Mei-Tsz; Lin, Sheng-Hsiang; Chen, Yi-Chi; Kuo, Pao-Lin

2014-06-01

Both vascular endothelial growth factor A (VEGFA) and endocrine gland-derived vascular endothelial growth factor (EG-VEGF) systems play major roles in angiogenesis. A body of evidence suggests VEGFs regulate critical processes during pregnancy and have been associated with recurrent pregnancy loss (RPL). However, little information is available regarding the interaction of these two major major angiogenesis-related systems in early human pregnancy. This study was conducted to investigate the association of gene polymorphisms and gene-gene interaction among genes in VEGFA and EG-VEGF systems and idiopathic RPL. A total of 98 women with history of idiopathic RPL and 142 controls were included, and 5 functional SNPs selected from VEGFA, KDR, EG-VEGF (PROK1), PROKR1 and PROKR2 were genotyped. We used multifactor dimensionality reduction (MDR) analysis to choose a best model and evaluate gene-gene interactions. Ingenuity pathways analysis (IPA) was introduced to explore possible complex interactions. Two receptor gene polymorphisms [KDR (Q472H) and PROKR2 (V331M)] were significantly associated with idiopathic RPL (P<0.01). The MDR test revealed that the KDR (Q472H) polymorphism was the best loci to be associated with RPL (P=0.02). IPA revealed EG-VEGF and VEGFA systems shared several canonical signaling pathways that may contribute to gene-gene interactions, including the Akt, IL-8, EGFR, MAPK, SRC, VHL, HIF-1A and STAT3 signaling pathways. Two receptor gene polymorphisms [KDR (Q472H) and PROKR2 (V331M)] were significantly associated with idiopathic RPL. EG-VEGF and VEGFA systems shared several canonical signaling pathways that may contribute to gene-gene interactions, including the Akt, IL-8, EGFR, MAPK, SRC, VHL, HIF-1A and STAT3.

Pathology Dynamics Predict Spinal Cord Injury Therapeutic Success

PubMed Central

Mitchell, Cassie S.

2008-01-01

Abstract Secondary injury, the complex cascade of cellular events following spinal cord injury (SCI), is a major source of post-insult neuron death. Experimental work has focused on the details of individual factors or mechanisms that contribute to secondary injury, but little is known about the interactions among factors leading to the overall pathology dynamics that underlie its propagation. Prior hypotheses suggest that the pathology is dominated by interactions, with therapeutic success lying in combinations of neuroprotective treatments. In this study, we provide the first comprehensive, system-level characterization of the entire secondary injury process using a novel relational model methodology that aggregates the findings of ~250 experimental studies. Our quantitative examination of the overall pathology dynamics suggests that, while the pathology is initially dominated by “fire-like,” rate-dependent interactions, it quickly switches to a “flood-like,” accumulation-dependent process with contributing factors being largely independent. Our evaluation of ~20,000 potential single and combinatorial treatments indicates this flood-like pathology results in few highly influential factors at clinically realistic treatment time frames, with multi-factor treatments being merely additive rather than synergistic in reducing neuron death. Our findings give new fundamental insight into the understanding of the secondary injury pathology as a whole, provide direction for alternative therapeutic strategies, and suggest that ultimate success in treating SCI lies in the pursuit of pathology dynamics in addition to individually involved factors. PMID:19125684

Identification of SNPs associated with variola virus virulence.

PubMed

Hoen, Anne Gatewood; Gardner, Shea N; Moore, Jason H

2013-02-14

Decades after the eradication of smallpox, its etiological agent, variola virus (VARV), remains a threat as a potential bioweapon. Outbreaks of smallpox around the time of the global eradication effort exhibited variable case fatality rates (CFRs), likely attributable in part to complex viral genetic determinants of smallpox virulence. We aimed to identify genome-wide single nucleotide polymorphisms associated with CFR. We evaluated unadjusted and outbreak geographic location-adjusted models of single SNPs and two- and three-way interactions between SNPs. Using the data mining approach multifactor dimensionality reduction (MDR), we identified five VARV SNPs in models significantly associated with CFR. The top performing unadjusted model and adjusted models both revealed the same two-way gene-gene interaction. We discuss the biological plausibility of the influence of the SNPs identified these and other significant models on the strain-specific virulence of VARV. We have identified genetic loci in the VARV genome that are statistically associated with VARV virulence as measured by CFR. While our ability to infer a causal relationship between the specific SNPs identified in our analysis and VARV virulence is limited, our results suggest that smallpox severity is in part associated with VARV strain variation and that VARV virulence may be determined by multiple genetic loci. This study represents the first application of MDR to the identification of pathogen gene-gene interactions for predicting infectious disease outbreak severity.

Association of VAMP5 and MCC genetic polymorphisms with increased risk of Hirschsprung disease susceptibility in Southern Chinese children.

PubMed

Zhao, Jinglu; Xie, Xiaoli; Yao, Yuxiao; He, Qiuming; Zhang, Ruizhong; Xia, Huimin; Zhang, Yan

2018-04-25

Hirschsprung disease (HSCR) is a genetic disorder characterized by the absence of neural crest cells in parts of the intestine. This study aims to investigate the association of vesicle-associated membrane protein 5 ( VAMP5 ) and mutated in colorectal cancer ( MCC ) genetic polymorphisms and their correlated risks with HSCR. We examined the association in four polymorphisms (rs10206961, rs1254900 and rs14242 in VAMP5 , rs11241200 in MCC ) and HSCR susceptibility in a Southern Chinese population composed of 1473 cases and 1469 controls. Two variants in VAMP5 were replicated as associated with HSCR. Interestingly, we clarified SNPs rs10206961 and rs1254900 in VAMP5 are more essential for patients with long-segment aganglionosis (LHSCR). Relatively high expression correlation was observed between VAMP5 and MCC using data from public database showing there may exist potential genetic interactions. SNP interaction was cross-examined by logistic regression and multifactor dimensionality reduction analysis revealing that VAMP5 rs1254900 and MCC rs11241200 were interacting significantly, thereby contributing to the risk of HSCR. The results suggest that significant associations of the rs10206961 and rs14242 in VAMP5 with an increased risk of HSCR in Southern Chinese, especially in LHSCR patients. This study provided new evidence of epistatic association of VAMP5 and MCC with increased risk of HSCR.

Artificial neural network-based exploration of gene-nutrient interactions in folate and xenobiotic metabolic pathways that modulate susceptibility to breast cancer.

PubMed

Naushad, Shaik Mohammad; Ramaiah, M Janaki; Pavithrakumari, Manickam; Jayapriya, Jaganathan; Hussain, Tajamul; Alrokayan, Salman A; Gottumukkala, Suryanarayana Raju; Digumarti, Raghunadharao; Kutala, Vijay Kumar

2016-04-15

In the current study, an artificial neural network (ANN)-based breast cancer prediction model was developed from the data of folate and xenobiotic pathway genetic polymorphisms along with the nutritional and demographic variables to investigate how micronutrients modulate susceptibility to breast cancer. The developed ANN model explained 94.2% variability in breast cancer prediction. Fixed effect models of folate (400 μg/day) and B12 (6 μg/day) showed 33.3% and 11.3% risk reduction, respectively. Multifactor dimensionality reduction analysis showed the following interactions in responders to folate: RFC1 G80A × MTHFR C677T (primary), COMT H108L × CYP1A1 m2 (secondary), MTR A2756G (tertiary). The interactions among responders to B12 were RFC1G80A × cSHMT C1420T and CYP1A1 m2 × CYP1A1 m4. ANN simulations revealed that increased folate might restore ER and PR expression and reduce the promoter CpG island methylation of extra cellular superoxide dismutase and BRCA1. Dietary intake of folate appears to confer protection against breast cancer through its modulating effects on ER and PR expression and methylation of EC-SOD and BRCA1. Copyright © 2016 Elsevier B.V. All rights reserved.

Identification of SNPs associated with variola virus virulence

PubMed Central

2013-01-01

Background Decades after the eradication of smallpox, its etiological agent, variola virus (VARV), remains a threat as a potential bioweapon. Outbreaks of smallpox around the time of the global eradication effort exhibited variable case fatality rates (CFRs), likely attributable in part to complex viral genetic determinants of smallpox virulence. We aimed to identify genome-wide single nucleotide polymorphisms associated with CFR. We evaluated unadjusted and outbreak geographic location-adjusted models of single SNPs and two- and three-way interactions between SNPs. Findings Using the data mining approach multifactor dimensionality reduction (MDR), we identified five VARV SNPs in models significantly associated with CFR. The top performing unadjusted model and adjusted models both revealed the same two-way gene-gene interaction. We discuss the biological plausibility of the influence of the SNPs identified these and other significant models on the strain-specific virulence of VARV. Conclusions We have identified genetic loci in the VARV genome that are statistically associated with VARV virulence as measured by CFR. While our ability to infer a causal relationship between the specific SNPs identified in our analysis and VARV virulence is limited, our results suggest that smallpox severity is in part associated with VARV strain variation and that VARV virulence may be determined by multiple genetic loci. This study represents the first application of MDR to the identification of pathogen gene-gene interactions for predicting infectious disease outbreak severity. PMID:23410064

The Effects of Legumes on Metabolic Features, Insulin Resistance and Hepatic Function Tests in Women with Central Obesity: A Randomized Controlled Trial

PubMed Central

Alizadeh, Mohammad; Gharaaghaji, Rasool; Gargari, Bahram Pourghassem

2014-01-01

Background: The effect of high-legume hypocaloric diet on metabolic features in women is unclear. This study provided an opportunity to find effects of high-legume diet on metabolic features in women who consumed high legumes at pre-study period. Methods: In this randomized controlled trial after 2 weeks of a run-in period on an isocaloric diet, 42 premenopausal women with central obesity were randomly assigned into two groups: (1) Hypocaloric diet enriched in legumes (HDEL) and (2) hypocaloric diet without legumes (HDWL) for 6 weeks. The following variables were assessed before intervention and 3 and 6 weeks after its beginning: Waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting serum concentrations of triglyceride (TG), high density lipoprotein cholesterol, fasting blood sugar (FBS), insulin, homeostasis model of insulin resistance (HOMA-IR), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). We used multifactor model of nested multivariate analysis of variance repeated measurements and t-test for statistical analysis. Results: HDEL and HDWL significantly reduced the WC. HDEL significantly reduced the SBP and TG. Both HDEL and HDWL significantly increased fasting concentration of insulin and HOMA-IR after 3 weeks, but their significant effects on insulin disappeared after 6 weeks and HDEL returned HOMA-IR to basal levels in the subsequent 3 weeks. In HDEL group percent of decrease in AST and ALT between 3rd and 6th weeks was significant. In HDWL group percent of increase in SBP, DBP, FBS and TG between 3rd and 6th weeks was significant. Conclusions: The study indicated beneficial effects of hypocaloric legumes on metabolic features. PMID:25013690

A Multi-Factor Analysis of Job Satisfaction among School Nurses

ERIC Educational Resources Information Center

Foley, Marcia; Lee, Julie; Wilson, Lori; Cureton, Virginia Young; Canham, Daryl

2004-01-01

Although job satisfaction has been widely studied among registered nurses working in traditional health care settings, little is known about the job-related values and perceptions of nurses working in school systems. Job satisfaction is linked to lower levels of job-related stress, burnout, and career abandonment among nurses. This study evaluated…

Investigating Teachers' Organizational Socialization Levels and Perceptions about Leadership Styles of Their Principals

ERIC Educational Resources Information Center

Kadi, Aysegül

2015-01-01

The purpose of this study is to investigate teachers' organizational socialization levels and perceptions about leadership styles of their principals. Research was conducted with 361 teachers. Research design is determined as survey and correlational. Multi-Factor Leadership Scale originally was developed by Bass (1999) and adapted to Turkish…

Authentic Leadership--Is It More than Emotional Intelligence?

ERIC Educational Resources Information Center

Duncan, Phyllis; Green, Mark; Gergen, Esther; Ecung, Wenonah

2017-01-01

One of the newest theories to gain widespread interest is authentic leadership. Part of the rationale for developing a model and subsequent instrument to measure authentic leadership was a concern that the more popular theory, the full range model of leadership and its instrument, the Multifactor Leadership Questionnaire (MLQ) (Bass & Avolio,…

Emotional Enhancement Effect of Memory: Removing the Influence of Cognitive Factors

ERIC Educational Resources Information Center

Sommer, Tobias; Glascher, Jan; Moritz, Steffen; Buchel, Christian

2008-01-01

According to the modulation hypothesis, arousal is the crucial factor in the emotional enhancement of memory (EEM). However, the multifactor theory of the EEM recently proposed that cognitive characteristics of emotional stimuli, e.g., relatedness and distinctiveness, also play an important role. The current study aimed to investigate the…

An ecological classification system for the central hardwoods region: The Hoosier National Forest

Treesearch

James E. Van Kley; George R. Parker

1993-01-01

This study, a multifactor ecological classification system, using vegetation, soil characteristics, and physiography, was developed for the landscape of the Hoosier National Forest in Southern Indiana. Measurements of ground flora, saplings, and canopy trees from selected stands older than 80 years were subjected to TWINSPAN classification and DECORANA ordination....

Multifactor Screener in the 2000 National Health Interview Survey Cancer Control Supplement: Scoring Procedures

Cancer.gov

Scoring procedures were developed to convert a respondent's screener responses to estimates of individual dietary intake for percentage energy from fat, grams of fiber, and servings of fruits and vegetables, using USDA's 1994-96 Continuing Survey of Food Intakes of Individuals (CSFII 94-96) dietary recall data.

Technical Notes on the Multifactor Method of Elementary School Closing.

ERIC Educational Resources Information Center

Puleo, Vincent T.

This report provides preliminary technical information on a method for analyzing the factors involved in the closing of elementary schools. Included is a presentation of data and a brief discussion bearing on descriptive statistics, reliability, and validity. An intercorrelation matrix is also examined. The method employs 9 factors that have a…

Motivating Peak Performance: Leadership Behaviors That Stimulate Employee Motivation and Performance

ERIC Educational Resources Information Center

Webb, Kerry

2007-01-01

The impact of leader behaviors on motivation levels of employees was examined in this study. Two hundred twenty-three vice presidents and chief officers from 104 member colleges and universities in the Council for Christian Colleges and Universities were sampled. Leaders were administered the Multifactor Leadership Questionnaire (MLQ-rater…

Faculty Member Perceptions of Academic Leadership Styles at Private Colleges

ERIC Educational Resources Information Center

Gidman, Lori Kathleen

2013-01-01

The leadership style of academic leaders was studied through the eyes of faculty members. This empirical study looked at faculty perceptions of academic leadership with the use of a numerical survey as the basis for observation. Faculty members at six private liberal arts institutions completed the Multifactor Leadership Questionnaire (MLQ) in…

The Relationship between School Principals' Leadership Styles and Collective Teacher Efficacy

ERIC Educational Resources Information Center

Akan, Durdagi

2013-01-01

This study aims to determine the relationship between school administrators' leadership styles and the collective teacher efficacy based on teachers' perceptions. In line with this objective, the multifactor leadership style scale and the collective teacher efficacy scale were applied on 223 teachers who were working in the province of Erzurum.…

Predicting plant species diversity in a longleaf pine landscape

Treesearch

L. Katherine Kirkman; P. Charles Goebel; Brian J. Palik; Larry T. West

2004-01-01

In this study, we used a hierarchical, multifactor ecological classification system to examine how spatial patterns of biodiversity develop in one of the most species-rich ecosystems in North America, the fire-maintained longleaf pine-wiregrass ecosystem and associated depressional wetlands and riparian forests. Our goal was to determine which landscape features are...

Goal Oriented and Risk Taking Behavior: The Roles of Multiple Systems for Caucasian and Arab-American Adolescents

ERIC Educational Resources Information Center

Tynan, Joshua J.; Somers, Cheryl L.; Gleason, Jamie H.; Markman, Barry S.; Yoon, Jina

2015-01-01

With Bronfenbrenner's (1977) ecological theory and other multifactor models (e.g. Pianta, 1999; Prinstein, Boergers, & Spirito, 2001) underlying this study design, the purpose was to examine, simultaneously, key variables in multiple life contexts (microsystem, mesosystem, exosystem levels) for their individual and combined roles in predicting…

A Study of Secondary School Principals' Leadership Styles and School Dropout Rates

ERIC Educational Resources Information Center

Baggerly-Hinojosa, Barbara

2012-01-01

This study examined the relationship between the leadership styles of secondary school principals, measured by the self-report "Multifactor Leadership Questionnaire 5X short" (Bass & Avolio, 2000) and the school's dropout rates, as reported by the Texas Education Agency in the Academic Excellence Indicator System (AEIS) report while…

Can Multifactor Models of Teaching Improve Teacher Effectiveness Measures?

ERIC Educational Resources Information Center

Lazarev, Valeriy; Newman, Denis

2014-01-01

NCLB waiver requirements have led to development of teacher evaluation systems, in which student growth is a significant component. Recent empirical research has been focusing on metrics of student growth--value-added scores in particular--and their relationship to other metrics. An extensive set of recent teacher-evaluation studies conducted by…

Estimating multi-factor cumulative watershed effects on fish populations with an individual-based model

Treesearch

Bret C. Harvey; Steven F. Railsback

2007-01-01

While the concept of cumulative effects is prominent in legislation governing environmental management, the ability to estimate cumulative effects remains limited. One reason for this limitation is that important natural resources such as fish populations may exhibit complex responses to changes in environmental conditions, particularly to alteration of multiple...

Bureaucratic Abuse and the False Dichotomy between Intentional and Unintentional Child Injuries.

ERIC Educational Resources Information Center

Kotch, Jonathan B.; And Others

This paper examines the arbitrary distinctions between intentional and unintentional child injuries, noting that a careful review of the literature of both child abuse and unintentional child injury revealed similarities among the risk factors associated with the two outcomes. A single, multifactor model of injury etiology, the ecologic model, is…

Evidence for gene-gene epistatic interactions among susceptibility loci for systemic lupus erythematosus.

PubMed

Hughes, Travis; Adler, Adam; Kelly, Jennifer A; Kaufman, Kenneth M; Williams, Adrienne H; Langefeld, Carl D; Brown, Elizabeth E; Alarcón, Graciela S; Kimberly, Robert P; Edberg, Jeffrey C; Ramsey-Goldman, Rosalind; Petri, Michelle; Boackle, Susan A; Stevens, Anne M; Reveille, John D; Sanchez, Elena; Martín, Javier; Niewold, Timothy B; Vilá, Luis M; Scofield, R Hal; Gilkeson, Gary S; Gaffney, Patrick M; Criswell, Lindsey A; Moser, Kathy L; Merrill, Joan T; Jacob, Chaim O; Tsao, Betty P; James, Judith A; Vyse, Timothy J; Alarcón-Riquelme, Marta E; Harley, John B; Richardson, Bruce C; Sawalha, Amr H

2012-02-01

Several confirmed genetic susceptibility loci for lupus have been described. To date, no clear evidence for genetic epistasis in lupus has been established. The aim of this study was to test for gene-gene interactions in a number of known lupus susceptibility loci. Eighteen single-nucleotide polymorphisms tagging independent and confirmed lupus susceptibility loci were genotyped in a set of 4,248 patients with lupus and 3,818 normal healthy control subjects of European descent. Epistasis was tested by a 2-step approach using both parametric and nonparametric methods. The false discovery rate (FDR) method was used to correct for multiple testing. We detected and confirmed gene-gene interactions between the HLA region and CTLA4, IRF5, and ITGAM and between PDCD1 and IL21 in patients with lupus. The most significant interaction detected by parametric analysis was between rs3131379 in the HLA region and rs231775 in CTLA4 (interaction odds ratio 1.19, Z = 3.95, P = 7.8 × 10(-5) [FDR ≤0.05], P for multifactor dimensionality reduction = 5.9 × 10(-45)). Importantly, our data suggest that in patients with lupus, the presence of the HLA lupus risk alleles in rs1270942 and rs3131379 increases the odds of also carrying the lupus risk allele in IRF5 (rs2070197) by 17% and 16%, respectively (P = 0.0028 and P = 0.0047, respectively). We provide evidence for gene-gene epistasis in systemic lupus erythematosus. These findings support a role for genetic interaction contributing to the complexity of lupus heritability. Copyright © 2012 by the American College of Rheumatology.

Interactions among variants in TXA2R, P2Y12 and GPIIIa are associated with carotid plaque vulnerability in Chinese population.

PubMed

Yi, Xingyang; Lin, Jing; Luo, Hua; Zhou, Ju; Zhou, Qiang; Wang, Yanfen; Wang, Chun

2018-04-03

The associations between variants in platelet activation-relevant genes and carotid plaque vulnerability are not fully understood. The aim of the present study was to investigate the associations of the variants in platelet activation-relevant genes and interactions among these variants with carotid plaque vulnerability. There were no significant differences in the frequencies of genotypes of the 11 variants between patients and controls. Among 396 patients, 102 patients had not carotid plaque, 106 had VP, and 188 had SP. The 11 variants were not independently associated with risk of carotid plaque vulnerability after adjusting for potential confounding variables. However, the GMDR analysis showed that there were synergistic effects of gene-gene interactions among TXA2Rr s1131882, GPIIIa rs2317676 and P2Y12 rs16863323 on carotid plaque vulnerability. The high-risk interactions among the three variants were associated with high platelet activation, and independently associated with the risk of carotid plaque vulnerability. Eleven variants in platelet activation-relevant genes were examined using mass spectrometry methods in 396 ischemic stroke patients and 291controls. Platelet-leukocyte aggregates and platelet aggregation were also measured. Carotid plaques were assessed by B-mode ultrasound. According to the results of ultrasound, the patients were stratified into three groups: non-plaque group, vulnerable plaque (VP) group and stable plaque (SP) group. Furthermore, gene-gene interactions were analyzed using generalized multifactor dimensionality reduction (GMDR) methods. The rs1131882, rs2317676, and rs16863323 three-loci interactions may confer a higher risk of carotid plaque vulnerability, and might be potential markers for plaque instability.

Haplotype-based gene-gene interaction of bone morphogenetic protein 4 and interferon regulatory factor 6 in the etiology of non-syndromic cleft lip with or without cleft palate in a Chilean population.

PubMed

Blanco, Rafael; Colombo, Alicia; Pardo, Rosa; Suazo, José

2017-04-01

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is the most common craniofacial birth defect in humans, the etiology of which can be dependent on the interactions of multiple genes. We previously reported haplotype associations for polymorphic variants of interferon regulatory factor 6 (IRF6), msh homeobox 1 (MSX1), bone morphogenetic protein 4 (BMP4), and transforming growth factor beta 3 (TGFB3) in Chile. Here, we analyzed the haplotype-based gene-gene interaction for markers of these genes and NSCL/P risk in the Chilean population. We genotyped 15 single nucleoptide polymorphisms (SNPs) in 152 Chilean patients and 164 controls. Linkage disequilibrium (LD) blocks were determined using the Haploview software, and phase reconstruction was performed by the Phase program. Haplotype-based interactions were evaluated using the multifactor dimensionality reduction (MDR) method. We detected two LD blocks composed of two SNPs from BMP4 (Block 1) and three SNPs from IRF6 (Block 2). Although MDR showed no statistical significance for the global interaction model involving these blocks, we found four combinations conferring a statistically significantly increased NSCL/P risk (Block 1-Block 2): T-T/T-G C-G-T/G-A-T; T-T/T-G C-G-C/C-G-C; T-T/T-G G-A-T/G-A-T; and T-T/C-G G-A-T/G-A-T. These findings may reflect the presence of a genomic region containing potential causal variants interacting in the etiology of NSCL/P and may contribute to disentangling the complex etiology of this birth defect. © 2017 Eur J Oral Sci.

Elevated air temperature alters an old-field insect community in a multi-factor climate change experiment

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

Villalpando, Sean; Williams, Ray; Norby, Richard J

To address how multiple, interacting climate drivers may affect plant-insect community associations, we sampled the insect community from a constructed old-field plant community grown under simultaneous [CO2], temperature, and water manipulation. Insects were identified to morphospecies, assigned to feeding guilds and abundance, richness and evenness quantified. Warming significantly increased Order Thysanoptera abundance and reduced overall morphospecies richness and evenness. Non-metric multidimensional scaling clearly supported the effect of warming on insect community composition. Reductions in richness for herbivores and parasitoids suggest trophic-level effects within the insect community. Analysis of dominant insects demonstrated the effects of warming were limited to a relativelymore » small number of morphospecies. Reported reductions in whole-community foliar N at elevated [CO2] unexpectedly did not result in any effects on herbivores. These results demonstrate climatic warming may alter certain insect communities via effects on insect species most responsive to higher temperature, contributing to a change in community structure.« less

Ideal discrimination of discrete clinical endpoints using multilocus genotypes.

PubMed

Hahn, Lance W; Moore, Jason H

2004-01-01

Multifactor Dimensionality Reduction (MDR) is a method for the classification and prediction of discrete clinical endpoints using attributes constructed from multilocus genotype data. Empirical studies with both real and simulated data suggest that MDR has good power for detecting gene-gene interactions in the absence of independent main effects. The purpose of this study is to develop an objective, theory-driven approach to evaluate the strengths and limitations of MDR. To accomplish this goal, we borrow concepts from ideal observer analysis used in visual perception to evaluate the theoretical limits of classifying and predicting discrete clinical endpoints using multilocus genotype data. We conclude that MDR ideally discriminates between low risk and high risk subjects using attributes constructed from multilocus genotype data. We also how that the classification approach used once a multilocus attribute is constructed is similar to that of a naive Bayes classifier. This study provides a theoretical foundation for the continued development, evaluation, and application of the MDR as a data mining tool in the domain of statistical genetics and genetic epidemiology.

Influence of solid waste and topography on urban floods: The case of Mexico City.

PubMed

Zambrano, Luis; Pacheco-Muñoz, Rodrigo; Fernández, Tania

2018-02-24

Floods in cities are increasingly common as a consequence of multifactor watershed dynamics, including geomorphology, land-use changes and land subsidence. However, urban managers have focused on infrastructure to address floods by reducing blocked sewage infrastructure, without significant success. Using Mexico City as a case study, we generated a spatial flood risk model with geomorphology and anthropogenic variables. The results helped contrast the implications of different public policies in land use and waste disposal, and correlating them with flood hazards. Waste disposal was only related to small floods. 58% of the city has a high risk of experiencing small floods, and 24% of the city has a risk for large floods. Half of the population with the lowest income is located in the high-risk areas for large floods. These models are easy to build, generate fast results and are able to help to flood policies, by understanding flood interactions in urban areas within the watershed.

Conference Attendance Patterns of Outdoor Orientation Program Staff at Four-Year Colleges in the United States

ERIC Educational Resources Information Center

Bell, Brent J.

2009-01-01

One purpose of professional conference attendance is to enhance social support. Intentionally fostering this support is an important political aim that should be developed. Although many multifactor definitions of social support exist (Cobb, 1979; Cohen & Syme, 1985; Kahn, 1979; Shaefer et al., 1981; Weiss, 1974), all distinguish between an…

Revisiting a Cognitive Framework for Test Design: Applications for a Computerized Perceptual Speed Test.

ERIC Educational Resources Information Center

Alderton, David L.

This paper highlights the need for a systematic, content aware, and theoretically-based approach to test design. The cognitive components approach is endorsed, and is applied to the development of a computerized perceptual speed test. Psychometric literature is reviewed and shows that: every major multi-factor theory includes a clerical/perceptual…

Bullying in Adolescent Residential Care: The Influence of the Physical and Social Residential Care Environment

ERIC Educational Resources Information Center

Sekol, Ivana

2016-01-01

Background: To date, no study examined possible contributions of environmental factors to bullying and victimization in adolescent residential care facilities. Objective: By testing one part of the Multifactor Model of Bullying in Secure Setting (MMBSS; Ireland in "Int J Adolesc Med Health" 24(1):63-68, 2012), this research examined the…

Academic Administrator Leadership Styles and the Impact on Faculty Job Satisfaction

ERIC Educational Resources Information Center

Bateh, Justin; Heyliger, Wilton

2014-01-01

This article examines the impact of three leadership styles as a predictor of job satisfaction in a state university system. The Multifactor Leadership Questionnaire was used to identify the leadership style of an administrator as perceived by faculty members. Spector's Job Satisfaction Survey was used to assess a faculty member's level of job…

The Impact of Mentor Leadership Styles on First-Year Adult Student Retention

ERIC Educational Resources Information Center

Smith Staley, Charlesetta

2012-01-01

This quantitative study explored the leadership styles of mentors for retained first-year adult students to analyze whether the prevalent style had a higher impact on first-year adult student retention. The Multifactor Leadership Questionnaire (MLQ) 5x was used to collect data on the mentors' leadership styles from the perspective of retained…

A Preliminary Study for a New Model of Sense of Community

ERIC Educational Resources Information Center

Tartaglia, Stefano

2006-01-01

Although Sense of Community (SOC) is usually defined as a multidimensional construct, most SOC scales are unidimensional. To reduce the split between theory and empirical research, the present work identifies a multifactor structure for the Italian Sense of Community Scale (ISCS) that has already been validated as a unitary index of SOC. This…

Creativity in the Structure of Professionalism of a Higher School Teacher

ERIC Educational Resources Information Center

Gladilina, Irina Petrovna

2016-01-01

In the science, due to the absence of strict and exact criteria for differentiating between creative and non-creative activities of a human, there is no rather full definition of "creativity" notion despite that this matter was addressed by many scholars. Multifactor field in the science on creativity allows interpreting the essence of…

Multifactor Screener in the 2000 National Health Interview Survey Cancer Control Supplement: Definition of Acceptable Dietary Data Values

Cancer.gov

We used the U.S. Department of Agriculture's (USDA) 1994-96 Continuing Survey of Food Intakes of Individuals (CSFII) data on reported intakes over two days of 24-hour recall to make judgments about reasonable frequencies of consumption that were reported on a per day basis.

Evaluating the metagenome of two sampling locations in the nasal cavity of cattle with bovine respiratory disease complex

USDA-ARS?s Scientific Manuscript database

Bovine respiratory disease complex (BRDC) is a multi-factor disease, and disease incidence may be associated with an animal’s commensal microbiota (metagenome). Evaluation of the animal’s resident microbiota in the nasal cavity may help us to understand the impact of the metagenome on incidence of ...

Evaluating the microbiome of two sampling locations in the nasal cavity of cattle with bovine respiratory disease complex (BRDC)

USDA-ARS?s Scientific Manuscript database

Bovine respiratory disease complex (BRDC) is a multi-factor disease, and disease incidence may be associated with an animal’s commensal microbiota (metagenome). Evaluation of the animal’s resident microbiota in the nasal cavity may help us to understand the impact of the metagenome on incidence of ...

The Effects of Transformational Leadership and the Sense of Calling on Job Burnout among Special Education Teachers

ERIC Educational Resources Information Center

Gong, Tao; Zimmerli, Laurie; Hoffer, Harry E.

2013-01-01

This article examines the effects of transformational leadership of supervisors and the sense of calling on job burnout among special education teachers. A total of 256 special education teachers completed the Maslach Burnout Inventory and rated their supervisors on the Multifactor Leadership Questionnaire. The results reveal that transformational…

Identifying the Best Buys in U.S. Higher Education

ERIC Educational Resources Information Center

Eff, E. Anthon; Klein, Christopher C.; Kyle, Reuben

2012-01-01

Which U.S. institutions of higher education offer the best value to consumers? To answer this question, we evaluate U.S. institutions relative to a data envelopment analysis (DEA) multi-factor frontier based on 2000-2001 data for 1,179 4-year institutions. The resulting DEA "best buy" scores allow the ranking of institutions by a…

Inside The Zone of Proximal Development: Validating A Multifactor Model Of Learning Potential With Gifted Students And Their Peers

ERIC Educational Resources Information Center

Kanevsky, Lannie; Geake, John

2004-01-01

Kanevsky (1995b) proposed a model of learning potential based on Vygotsky?s notions of "good learning" and the zone of proximal development. This study investigated the contributions of general knowledge, information processing efficiency, and metacognition to differences in the learning potential of 5 gifted nongifted students.…

[Relationship between pre-pregnant body mass index, maternal weight gain and small for gestational age].

PubMed

Peng, Tingting; Yue, Fujuan; Wang, Fang; Feng, Yongliang; Wu, Weiwei; Wang, Suping; Zhang, Yawei; Yang, Hailan

2015-06-01

To investigate the relationship between maternal pre-pregnancy body mass index, weight gain during pregnancy and small for gestational age (SGA) birth so as to provide evidence for the development of comprehensive prevention programs on SGA birth. Between March, 2012 and July, 2014, 4 754 pregnant women were asked to fill in the questionnaires which were collected from the First Affiliated Hospital of Shanxi Medical University. Data related to general demographic characteristics, pregnancy and health status of those pregnant women was collected and maternal pre-pregnancy body mass index and maternal weight gain were calculated. Subjects were divided into different groups before the effect of maternal pre-pregnancy body mass index and weight gain during pregnancy on SGA birth were estimated. The overall incidence of SGA birth was 9.26% (440/4 754). Proportions of SGA birth from pre-pregnant, underweight group, normal weight group, overweight and obese groups were 9.85%, 8.54% and 9.45%, respectively. Results from multi-factor logistic regression analyses showed that after adjusting the confounding factors as age, history on pregnancies etc., women with high pre-pregnancy BMI showed a lower incidence of SGA than those under normal pre-pregnancy BMI (OR = 0.714, 95% CI: 0.535-0.953). Different weight gains during pregnancy were statistically significant (χ(2) = 8.811, P = 0.012). Incidence of SGA birth that was below the recommended range in the 2009 Institute of Medicine Guidelines (12.20%) was higher than those within (9.23%) or beyond (8.45%) the recommended range. Results from the multi-factor logistic regression analyses showed that, after adjusting the confounding factors as age, pregnancy history etc., factor as weight gain below the recommended level could increase the risk of SGA (OR = 1.999, 95% CI: 1.487-2.685). In the underweight, normal weight, overweight or obese groups, with weight gain during pregnancy below the range, the incidence of SGA showed an increase (OR = 2.558, 95% CI: 1.313-4.981, OR = 1.804, 95% CI: 1.258-2.587, OR = 3.108, 95% CI: 1.237-7.811). There was no interaction of addictive or multiplicative models between these two factors under 'interaction analysis'. Women with high pre-pregnancy BMI presented a lower incidence of SGA than those within the normal range. Insufficient weight gain during pregnancy could increase the risk of SGA delivery. These findings called for attention to be paid to the gestational weight gain, in order to decrease the risk of SGA.

No Association Between Variant N-acetyltransferase Genes, Cigarette Smoking and Prostate Cancer Susceptibility Among Men of African Descent

PubMed Central

Kidd, La Creis Renee; VanCleave, Tiva T.; Doll, Mark A.; Srivastava, Daya S.; Thacker, Brandon; Komolafe, Oyeyemi; Pihur, Vasyl; Brock, Guy N.; Hein, David W.

2011-01-01

Objective We evaluated the individual and combination effects of NAT1, NAT2 and tobacco smoking in a case-control study of 219 incident prostate cancer (PCa) cases and 555 disease-free men. Methods Allelic discriminations for 15 NAT1 and NAT2 loci were detected in germ-line DNA samples using Taqman polymerase chain reaction (PCR) assays. Single gene, gene-gene and gene-smoking interactions were analyzed using logistic regression models and multi-factor dimensionality reduction (MDR) adjusted for age and subpopulation stratification. MDR involves a rigorous algorithm that has ample statistical power to assess and visualize gene-gene and gene-environment interactions using relatively small samples sizes (i.e., 200 cases and 200 controls). Results Despite the relatively high prevalence of NAT1*10/*10 (40.1%), NAT2 slow (30.6%), and NAT2 very slow acetylator genotypes (10.1%) among our study participants, these putative risk factors did not individually or jointly increase PCa risk among all subjects or a subset analysis restricted to tobacco smokers. Conclusion Our data do not support the use of N-acetyltransferase genetic susceptibilities as PCa risk factors among men of African descent; however, subsequent studies in larger sample populations are needed to confirm this finding. PMID:21709725

Climate and atmosphere simulator for experiments on ecological systems in changing environments.

PubMed

Verdier, Bruno; Jouanneau, Isabelle; Simonnet, Benoit; Rabin, Christian; Van Dooren, Tom J M; Delpierre, Nicolas; Clobert, Jean; Abbadie, Luc; Ferrière, Régis; Le Galliard, Jean-François

2014-01-01

Grand challenges in global change research and environmental science raise the need for replicated experiments on ecosystems subjected to controlled changes in multiple environmental factors. We designed and developed the Ecolab as a variable climate and atmosphere simulator for multifactor experimentation on natural or artificial ecosystems. The Ecolab integrates atmosphere conditioning technology optimized for accuracy and reliability. The centerpiece is a highly contained, 13-m(3) chamber to host communities of aquatic and terrestrial species and control climate (temperature, humidity, rainfall, irradiance) and atmosphere conditions (O2 and CO2 concentrations). Temperature in the atmosphere and in the water or soil column can be controlled independently of each other. All climatic and atmospheric variables can be programmed to follow dynamical trajectories and simulate gradual as well as step changes. We demonstrate the Ecolab's capacity to simulate a broad range of atmospheric and climatic conditions, their diurnal and seasonal variations, and to support the growth of a model terrestrial plant in two contrasting climate scenarios. The adaptability of the Ecolab design makes it possible to study interactions between variable climate-atmosphere factors and biotic disturbances. Developed as an open-access, multichamber platform, this equipment is available to the international scientific community for exploring interactions and feedbacks between ecological and climate systems.

A computational intelligent approach to multi-factor analysis of violent crime information system

NASA Astrophysics Data System (ADS)

Liu, Hongbo; Yang, Chao; Zhang, Meng; McLoone, Seán; Sun, Yeqing

2017-02-01

Various scientific studies have explored the causes of violent behaviour from different perspectives, with psychological tests, in particular, applied to the analysis of crime factors. The relationship between bi-factors has also been extensively studied including the link between age and crime. In reality, many factors interact to contribute to criminal behaviour and as such there is a need to have a greater level of insight into its complex nature. In this article we analyse violent crime information systems containing data on psychological, environmental and genetic factors. Our approach combines elements of rough set theory with fuzzy logic and particle swarm optimisation to yield an algorithm and methodology that can effectively extract multi-knowledge from information systems. The experimental results show that our approach outperforms alternative genetic algorithm and dynamic reduct-based techniques for reduct identification and has the added advantage of identifying multiple reducts and hence multi-knowledge (rules). Identified rules are consistent with classical statistical analysis of violent crime data and also reveal new insights into the interaction between several factors. As such, the results are helpful in improving our understanding of the factors contributing to violent crime and in highlighting the existence of hidden and intangible relationships between crime factors.

[Influence of leptin receptor gene K109R polymorphism on the risk of nonalcoholic fatty liver disease and its interaction with PNPLA3 I148M polymorphism].

PubMed

An, B Q; Jiang, M; Cheng, Y T; Yuan, C; Lu, L L; Xin, Y N; Xuan, S Y

2016-05-20

To investigate the influence of leptin receptor (LEPR) gene K109R polymorphism on the risk of nonalcoholic fatty liver disease (NAFLD) and its interaction with PNPLA3 I148M polymorphism in the Han Chinese population in Qingdao, China. Blood samples were collected from 296 NAFLD patients and 321 healthy controls, and the genotypes of these patients were determined by PCR and genotyping. Related statistical analyses were performed to compare genotypes, alleles, and clinical data between the two groups. Generalized multifactor dimensionality reduction (GMDR) was used to investigate the interaction between LEPR K109R and PNPLA3 I148M genes. The distribution of LEPR K109R genotypes and alleles showed no significant differences between the NAFLD group and the control group (P > 0.05). PNPLA3 I148M gene polymorphisms were closely associated with the risk of NAFLD, and the risk of NAFLD in G mutant gene carriers was 2.07 times that in patients who did not carry this gene (OR = 2.07, 95% CI 1.423-3.013, P < 0.001). The joint action of LEPR K109R and PNPLA3 I148M significantly increased the risk of NAFL (OR = 3.393, 95% CI 1.856-6.201, P < 0.001). In the Han Chinese population in Qingdao, LEPR K109R gene polymorphism is not associated with the risk of NAFLD, but its interaction with PNPLA3 I148M polymorphism can significantly increase the risk of NAFLD.

Epistasis Analysis for Estrogen Metabolic and Signaling Pathway Genes on Young Ischemic Stroke Patients

PubMed Central

Hsieh, Yi-Chen; Jeng, Jiann-Shing; Lin, Huey-Juan; Hu, Chaur-Jong; Yu, Chia-Chen; Lien, Li-Ming; Peng, Giia-Sheun; Chen, Chin-I; Tang, Sung-Chun; Chi, Nai-Fang; Tseng, Hung-Pin; Chern, Chang-Ming; Hsieh, Fang-I; Bai, Chyi-Huey; Chen, Yi-Rhu; Chiou, Hung-Yi; Jeng, Jiann-Shing; Tang, Sung-Chun; Yeh, Shin-Joe; Tsai, Li-Kai; Kong, Shin; Lien, Li-Ming; Chiu, Hou-Chang; Chen, Wei-Hung; Bai, Chyi-Huey; Huang, Tzu-Hsuan; Chi-Ieong, Lau; Wu, Ya-Ying; Yuan, Rey-Yue; Hu, Chaur-Jong; Sheu, Jau- Jiuan; Yu, Jia-Ming; Ho, Chun-Sum; Chen, Chin-I; Sung, Jia-Ying; Weng, Hsing-Yu; Han, Yu-Hsuan; Huang, Chun-Ping; Chung, Wen-Ting; Ke, Der-Shin; Lin, Huey-Juan; Chang, Chia-Yu; Yeh, Poh-Shiow; Lin, Kao-Chang; Cheng, Tain-Junn; Chou, Chih-Ho; Yang, Chun-Ming; Peng, Giia-Sheun; Lin, Jiann-Chyun; Hsu, Yaw-Don; Denq, Jong-Chyou; Lee, Jiunn-Tay; Hsu, Chang-Hung; Lin, Chun-Chieh; Yen, Che-Hung; Cheng, Chun-An; Sung, Yueh-Feng; Chen, Yuan-Liang; Lien, Ming-Tung; Chou, Chung-Hsing; Liu, Chia-Chen; Yang, Fu-Chi; Wu, Yi-Chung; Tso, An-Chen; Lai, Yu- Hua; Chiang, Chun-I; Tsai, Chia-Kuang; Liu, Meng-Ta; Lin, Ying-Che; Hsu, Yu-Chuan; Chen, Chih-Hung; Sung, Pi-Shan; Chern, Chang-Ming; Hu, Han-Hwa; Wong, Wen-Jang; Luk, Yun-On; Hsu, Li-Chi; Chung, Chih-Ping; Tseng, Hung-Pin; Liu, Chin-Hsiung; Lin, Chun-Liang; Lin, Hung-Chih; Hu, Chaur-Jong

2012-01-01

Background Endogenous estrogens play an important role in the overall cardiocirculatory system. However, there are no studies exploring the hormone metabolism and signaling pathway genes together on ischemic stroke, including sulfotransferase family 1E (SULT1E1), catechol-O-methyl-transferase (COMT), and estrogen receptor α (ESR1). Methods A case-control study was conducted on 305 young ischemic stroke subjects aged ≦ 50 years and 309 age-matched healthy controls. SULT1E1 -64G/A, COMT Val158Met, ESR1 c.454−397 T/C and c.454−351 A/G genes were genotyped and compared between cases and controls to identify single nucleotide polymorphisms associated with ischemic stroke susceptibility. Gene-gene interaction effects were analyzed using entropy-based multifactor dimensionality reduction (MDR), classification and regression tree (CART), and traditional multiple regression models. Results COMT Val158Met polymorphism showed a significant association with susceptibility of young ischemic stroke among females. There was a two-way interaction between SULT1E1 -64G/A and COMT Val158Met in both MDR and CART analysis. The logistic regression model also showed there was a significant interaction effect between SULT1E1 -64G/A and COMT Val158Met on ischemic stroke of the young (P for interaction = 0.0171). We further found that lower estradiol level could increase the risk of young ischemic stroke for those who carry either SULT1E1 or COMT risk genotypes, showing a significant interaction effect (P for interaction = 0.0174). Conclusions Our findings support that a significant epistasis effect exists among estrogen metabolic and signaling pathway genes and gene-environment interactions on young ischemic stroke subjects. PMID:23112845

Association of Cytochrome P450 Genetic Variants with Clopidogrel Resistance and Outcomes in Acute Ischemic Stroke

PubMed Central

Yi, Xingyang; Wang, Yanfen; Zhou, Qiang; Wang, Chun; Cheng, Wen; Chi, Lifen

2016-01-01

Aims: Clopidogrel is an antiplatelet drug primarily used to treat or prevent acute ischemic stroke (IS) or myocardial infarction (MI). This prodrug requires biotransformation to an active metabolite by cytochrome P450 (CYP) enzymes, and CYP single nucleotide polymorphisms (SNPs) could affect the efficiency of such biotransformation. Methods: A total of 375 consecutive IS patients were genotyped for eight CYP SNPs using mass spectrometry. Platelet aggregation activity was measured before and after the 7 – 10 day treatment. Gene–gene interactions were analyzed using generalized multifactor dimensionality reduction (GMDR) analysis. All patients received clopidogrel therapy and were followed up for six months. Primary outcomes were evaluated as a composite of recurrent ischemic stroke (RIS), MI, and death. The secondary outcome was the modified Rankin Scale (mRS). Results: Clopidogrel resistance occurred in 153 patients (40.8%). The frequency of CYP3A5 (rs776746) GG/AG and CYP2C19*2 (rs4244285) AA/AG genotypes was significantly higher in clopidogrel-resistant patients than in sensitive patients. There was a significant gene-gene interaction between CYP3A5 (rs776746) and CYP2C19*2 (rs4244285). CYP2C19*2 AA and its interaction with CYP3A5 GG were independent predictors of clopidogrel resistance and affected the activity of platelet aggregation. Diabetes mellitus, CYP2C19*2 (rs4244285), clopidogrel resistance, and the interaction of CYP2C19*2 with CYP3A5 were all independent risk factors for the primary outcomes of clopidogrel treatment. Clopidogrel-resistant patients were more likely to have poor outcomes (mRS > 2 points) compared with clopidogrel-sensitive patients. Conclusion: CYP SNPs and their interactions are associated with drug resistance and outcomes in acute IS patients. PMID:26961113

Interaction of CYP2C19, P2Y12, and GPIIIa Variants Associates With Efficacy of Clopidogrel and Adverse Events on Patients With Ischemic Stroke.

PubMed

Yi, Xingyang; Wang, Yanfen; Lin, Jing; Cheng, Wen; Zhou, Qiang; Wang, Chun

2017-10-01

Clopidogrel is a clinically important oral antiplatelet agent for the treatment or prevention of cerebrovascular disease. However, different individuals have different sensitivities to clopidogrel. This study assessed variants of different genes for association with response to clopidogrel, clinical outcome, and side effects in patients with ischemic stroke (IS). We consecutively enrolled 375 patients with IS after they received clopidogrel therapy, and venous blood samples were subjected to genotyping allelic variants of genes modulating clopidogrel absorption (ATP binding cassette subfamily B1, ABCB1), metabolic activation (cytochrome P450[CYP] 3A and CYP2C19), and biologic activity (platelet membrane receptor [ P2Y12, P2Y1)], and glycoprotein IIIa [ GPIIIa]) and statistically analyzing their interactions with clopidogrel sensitivity (CS) and adverse events, risk of IS recurrence, myocardial infarction, and death during 6 months of follow-up. Adverse events occurred in 37 patients (31 had IS recurrence, 4 died, and 2 had myocardial infarction) during the first 6 months of follow-up. Single locus analysis showed that only the CYP2C19*2(rs4244285) variant was independently associated with CS and risk of adverse events after adjusting covariates. However, there was significant gene-gene interaction among CYP2C19*2(rs4244285), P2Y12(rs16863323), and GPIIIa (rs2317676) analyzed by generalized multifactor dimensionality reduction methods. The rate of adverse events among patients with the 3-loci interaction was 2.82 times the rate among those with no interaction (95% confidence interval: 2.04-8.63). Sensitivity of patients with IS to clopidogrel and clopidogrel-induced adverse clinical events may be multifactorial but is not determined by single gene polymorphisms.

Interactive effects of global change factors on soil respiration and its components: a meta-analysis.

PubMed

Zhou, Lingyan; Zhou, Xuhui; Shao, Junjiong; Nie, Yuanyuan; He, Yanghui; Jiang, Liling; Wu, Zhuoting; Hosseini Bai, Shahla

2016-09-01

As the second largest carbon (C) flux between the atmosphere and terrestrial ecosystems, soil respiration (Rs) plays vital roles in regulating atmospheric CO2 concentration ([CO2 ]) and climatic dynamics in the earth system. Although numerous manipulative studies and a few meta-analyses have been conducted to determine the responses of Rs and its two components [i.e., autotrophic (Ra) and heterotrophic (Rh) respiration] to single global change factors, the interactive effects of the multiple factors are still unclear. In this study, we performed a meta-analysis of 150 multiple-factor (≥2) studies to examine the main and interactive effects of global change factors on Rs and its two components. Our results showed that elevated [CO2 ] (E), nitrogen addition (N), irrigation (I), and warming (W) induced significant increases in Rs by 28.6%, 8.8%, 9.7%, and 7.1%, respectively. The combined effects of the multiple factors, EN, EW, DE, IE, IN, IW, IEW, and DEW, were also significantly positive on Rs to a greater extent than those of the single-factor ones. For all the individual studies, the additive interactions were predominant on Rs (90.6%) and its components (≈70.0%) relative to synergistic and antagonistic ones. However, the different combinations of global change factors (e.g., EN, NW, EW, IW) indicated that the three types of interactions were all important, with two combinations for synergistic effects, two for antagonistic, and five for additive when at least eight independent experiments were considered. In addition, the interactions of elevated [CO2 ] and warming had opposite effects on Ra and Rh, suggesting that different processes may influence their responses to the multifactor interactions. Our study highlights the crucial importance of the interactive effects among the multiple factors on Rs and its components, which could inform regional and global models to assess the climate-biosphere feedbacks and improve predictions of the future states of the ecological and climate systems. © 2016 John Wiley & Sons Ltd.

Genome-wide search followed by replication reveals genetic interaction of CD80 and ALOX5AP associated with systemic lupus erythematosus in Asian populations.

PubMed

Zhang, Yan; Yang, Jing; Zhang, Jing; Sun, Liangdan; Hirankarn, Nattiya; Pan, Hai-Feng; Lau, Chak Sing; Chan, Tak Mao; Lee, Tsz Leung; Leung, Alexander Moon Ho; Mok, Chi Chiu; Zhang, Lu; Wang, Yongfei; Shen, Jiangshan Jane; Wong, Sik Nin; Lee, Ka Wing; Ho, Marco Hok Kung; Lee, Pamela Pui Wah; Chung, Brian Hon-Yin; Chong, Chun Yin; Wong, Raymond Woon Sing; Mok, Mo Yin; Wong, Wilfred Hing Sang; Tong, Kwok Lung; Tse, Niko Kei Chiu; Li, Xiang-Pei; Avihingsanon, Yingyos; Rianthavorn, Pornpimol; Deekajorndej, Thavatchai; Suphapeetiporn, Kanya; Shotelersuk, Vorasuk; Ying, Shirley King Yee; Fung, Samuel Ka Shun; Lai, Wai Ming; Wong, Chun-Ming; Ng, Irene Oi Lin; Garcia-Barcelo, Maria-Merce; Cherny, Stacey S; Cui, Yong; Sham, Pak Chung; Yang, Sen; Ye, Dong-Qing; Zhang, Xue-Jun; Lau, Yu Lung; Yang, Wanling

2016-05-01

Genetic interaction has been considered as a hallmark of the genetic architecture of systemic lupus erythematosus (SLE). Based on two independent genome-wide association studies (GWAS) on Chinese populations, we performed a genome-wide search for genetic interactions contributing to SLE susceptibility. The study involved a total of 1 659 cases and 3 398 controls in the discovery stage and 2 612 cases and 3 441 controls in three cohorts for replication. Logistic regression and multifactor dimensionality reduction were used to search for genetic interaction. Interaction of CD80 (rs2222631) and ALOX5AP (rs12876893) was found to be significantly associated with SLE (OR_int=1.16, P_int_all=7.7E-04 at false discovery rate<0.05). Single nuclear polymorphism rs2222631 was found associated with SLE with genome-wide significance (P_all=4.5E-08, OR=0.86) and is independent of rs6804441 in CD80, whose association was reported previously. Significant correlation was observed between expression of these two genes in healthy controls and SLE cases, together with differential expression of these genes between cases and controls, observed from individuals from the Hong Kong cohort. Genetic interactions between BLK (rs13277113) and DDX6 (rs4639966), and between TNFSF4 (rs844648) and PXK (rs6445975) were also observed in both GWAS data sets. Our study represents the first genome-wide evaluation of epistasis interactions on SLE and the findings suggest interactions and independent variants may help partially explain missing heritability for complex diseases. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Heterogeneity in the Effect of Common Shocks on Healthcare Expenditure Growth.

PubMed

Hauck, Katharina; Zhang, Xiaohui

2016-09-01

Healthcare expenditure growth is affected by important unobserved common shocks such as technological innovation, changes in sociological factors, shifts in preferences, and the epidemiology of diseases. While common factors impact in principle all countries, their effect is likely to differ across countries. To allow for unobserved heterogeneity in the effects of common shocks, we estimate a panel data model of healthcare expenditure growth in 34 OECD countries over the years 1980 to 2012, where the usual fixed or random effects are replaced by a multifactor error structure. We address model uncertainty with Bayesian model averaging, to identify a small set of robust expenditure drivers from 43 potential candidates. We establish 16 significant drivers of healthcare expenditure growth, including growth in GDP per capita and in insurance premiums, changes in financing arrangements and some institutional characteristics, expenditures on pharmaceuticals, population ageing, costs of health administration, and inpatient care. Our approach allows us to provide robust evidence to policy makers on the drivers that were most strongly associated with the growth in healthcare expenditures over the past 32 years. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Adjunctive dental therapy via tooth plaque reduction and gingivitis treatment by blue light-emitting diodes tooth brushing

NASA Astrophysics Data System (ADS)

Genina, Elina A.; Titorenko, Vladimir A.; Belikov, Andrey V.; Bashkatov, Alexey N.; Tuchin, Valery V.

2015-12-01

The efficacy of blue light-emitting toothbrushes (B-LETBs) (405 to 420 nm, power density 2 mW/cm2) for reduction of dental plaques and gingival inflammation has been evaluated. Microbiological study has shown the multifactor therapeutic action of the B-LETBs on oral pathological microflora: in addition to partial mechanical removal of bacteria, photodynamic action suppresses them up to 97.5%. In the pilot clinical studies, subjects with mild to moderate gingivitis have been randomly divided into two groups: a treatment group that used the B-LETBs and a control group that used standard toothbrushes. Indices of plaque, gingival bleeding, and inflammation have been evaluated. A significant improvement of all dental indices in comparison with the baseline (by 59%, 66%, and 82% for plaque, gingival bleeding, and inflammation, respectively) has been found. The treatment group has demonstrated up to 50% improvement relative to the control group. We have proposed the B-LETBs to serve for prevention of gingivitis or as an alternative to conventional antibiotic treatment of this disease due to their effectiveness and the absence of drug side effects and bacterial resistance.

Adjunctive dental therapy via tooth plaque reduction and gingivitis treatment by blue light-emitting diodes tooth brushing.

PubMed

Genina, Elina A; Titorenko, Vladimir A; Belikov, Andrey V; Bashkatov, Alexey N; Tuchin, Valery V

2015-01-01

The efficacy of blue light-emitting toothbrushes (B-LETBs) (405 to 420 nm, power density 2  mW/cm(2)) for reduction of dental plaques and gingival inflammation has been evaluated. Microbiological study has shown the multifactor therapeutic action of the B-LETBs on oral pathological microflora: in addition to partial mechanical removal of bacteria, photodynamic action suppresses them up to 97.5%. In the pilot clinical studies, subjects with mild to moderate gingivitis have been randomly divided into two groups: a treatment group that used the B-LETBs and a control group that used standard toothbrushes. Indices of plaque, gingival bleeding, and inflammation have been evaluated. A significant improvement of all dental indices in comparison with the baseline (by 59%, 66%, and 82% for plaque, gingival bleeding, and inflammation, respectively) has been found. The treatment group has demonstrated up to 50% improvement relative to the control group. We have proposed the B-LETBs to serve for prevention of gingivitis or as an alternative to conventional antibiotic treatment of this disease due to their effectiveness and the absence of drug side effects and bacterial resistance.

Bullying among Adolescents in North Cyprus and Turkey: Testing a Multifactor Model

ERIC Educational Resources Information Center

Bayraktar, Fatih

2012-01-01

Peer bullying has been studied since the 1970s. Therefore, a vast literature has accumulated about the various predictors of bullying. However, to date there has been no study which has combined individual-, peer-, parental-, teacher-, and school-related predictors of bullying within a model. In this sense, the main aim of this study was to test a…

Electronic Health Records: Applying Diffusion of Innovation Theory to the Relationship between Multifactor Authentication and EHR Adoption

ERIC Educational Resources Information Center

Lockett, Daeron C.

2014-01-01

Electronic Health Record (EHR) systems are increasingly becoming accepted as future direction of medical record management systems. Programs such as the American Recovery and Reinvestment Act have provided incentives to hospitals that adopt EHR systems. In spite of these incentives, the perception of EHR adoption is that is has not achieved the…

Cross-Cultural Comparisons of University Students' Science Learning Self-Efficacy: Structural Relationships among Factors within Science Learning Self-Efficacy

ERIC Educational Resources Information Center

Wang, Ya-Ling; Liang, Jyh-Chong; Tsai, Chin-Chung

2018-01-01

Science learning self-efficacy could be regarded as a multi-factor belief which comprises different aspects such as cognitive skills, practical work, and everyday application. However, few studies have investigated the relationships among these factors that compose science learning self-efficacy. Also, culture may play an important role in…

The Four-Factor Model of Depressive Symptoms in Dementia Caregivers: A Structural Equation Model of Ethnic Differences

PubMed Central

Roth, David L.; Ackerman, Michelle L.; Okonkwo, Ozioma C.; Burgio, Louis D.

2008-01-01

Previous studies have suggested that 4 latent constructs (depressed affect, well-being, interpersonal problems, somatic symptoms) underlie the item responses on the Center for Epidemiological Studies Depression (CES-D) Scale. This instrument has been widely used in dementia caregiving research, but the fit of this multifactor model and the explanatory contributions of multifactor models have not been sufficiently examined for caregiving samples. The authors subjected CES-D data (N = 1,183) from the initial Resources for Enhancing Alzheimer’s Caregiver Health Study to confirmatory factor analysis methods and found that the 4-factor model provided excellent fit to the observed data. Invariance analyses suggested only minimal item-loading differences across race subgroups and supported the validity of race comparisons on the latent factors. Significant race differences were found on 3 of the 4 latent factors both before and after controlling for demographic covariates. African Americans reported less depressed affect and better well-being than White caregivers, who reported better well-being and fewer interpersonal problems than Hispanic caregivers. These findings clarify and extend previous studies of race differences in depression among diverse samples of dementia caregivers. PMID:18808246

[Risk factors in the living environment of early spontaneous abortion pregnant women].

PubMed

Liu, Xin-yan; Bian, Xu-ming; Han, Jing-xiu; Cao, Zhao-jin; Fan, Guang-sheng; Zhang, Chao; Zhang, Wen-li; Zhang, Shu-zhen; Sun, Xiao-guang

2007-10-01

To study the relationship between early spontaneous abortion and living environment, and explore the risk factors of spontaneous abortion. We conducted analysis based on the interview of 200 spontaneous abortion cases and the matched control (age +/- 2 years) by using multifactor Logistic regression analysis. The proportions of watching TV > or =10 hours/week, operating computer > or =45 hours/week, using copycat, microwave oven and mobile phone, electromagnetism equipment near the dwell or work place, e. g. switch room < or =50 m and launching tower < or =500 m in the cases are significantly higher than those in the controls in single factor analysis (all P < 0.05). After adjusted the effect of other risk factors by multifactor analysis, using microwave oven and mobile phone, contacting abnormal smell of fitment material > or =3 months, having emotional stress during the first term of pregnancy and spontaneous abortion history were significantly associated with risk of spontaneous abortion. The odds ratios of these risk factors were 2.23 and 4.63, respectively. Using microwave oven and mobile phone, contacting abnormal smell of fitment material > or =3 months, having emotional stress during the first term of pregnancy, and spontaneous abortion history are risk factors of early spontaneous abortion.

Fuzzy comprehensive evaluation of multiple environmental factors for swine building assessment and control.

PubMed

Xie, Qiuju; Ni, Ji-Qin; Su, Zhongbin

2017-10-15

In confined swine buildings, temperature, humidity, and air quality are all important for animal health and productivity. However, the current swine building environmental control is only based on temperature; and evaluation and control methods based on multiple environmental factors are needed. In this paper, fuzzy comprehensive evaluation (FCE) theory was adopted for multi-factor assessment of environmental quality in two commercial swine buildings using real measurement data. An assessment index system and membership functions were established; and predetermined weights were given using analytic hierarchy process (AHP) combined with knowledge of experts. The results show that multi-factors such as temperature, humidity, and concentrations of ammonia (NH 3 ), carbon dioxide (CO 2 ), and hydrogen sulfide (H 2 S) can be successfully integrated in FCE for swine building environment assessment. The FCE method has a high correlation coefficient of 0.737 compared with the method of single-factor evaluation (SFE). The FCE method can significantly increase the sensitivity and perform an effective and integrative assessment. It can be used as part of environmental controlling and warning systems for swine building environment management to improve swine production and welfare. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of Sulfate, Chloride, and Bicarbonate on Iron Stability in a PVC-U Drinking Pipe

PubMed Central

Wang, Jiaying; Tao, Tao; Yan, Hexiang

2017-01-01

In order to describe iron stability in plastic pipes and to ensure the drinking water security, the influence factors and rules for iron adsorption and release were studied, dependent on the Unplasticized poly (vinyl chloride) (PVC-U) drinking pipes employed in this research. In this paper, sulfate, chloride, and bicarbonate, as well as synthesized models, were chosen to investigate the iron stability on the inner wall of PVC-U drinking pipes. The existence of the three kinds of anions could significantly affect the process of iron adsorption, and a positive association was found between the level of anion concentration and the adsorption rate. However, the scaling formed on the inner surface of the pipes would be released into the water under certain conditions. The Larson Index (LI), used for a synthetic consideration of anion effects on iron stability, was selected to investigate the iron release under multi-factor conditions. Moreover, a well fitted linear model was established to gain a better understanding of iron release under multi-factor conditions. The simulation results demonstrated that the linear model was better fitted than the LI model for the prediction of iron release. PMID:28629192

System development over the monitoring for the purpose of early warning of population from the threat of landslides. (Invited)

NASA Astrophysics Data System (ADS)

Zakhidova, D. V.; Kadyrhodjaev, A.; Scientific Team Of Hydroengeo Institute On Natural Hazards

2010-12-01

Well-timed warning of the population about possible landslide threat is one of the main positions in order to provide safe and stable country development. The system of monitoring over dangerous geological processes includes such components, as observation, forecast, control and management. Aspects of forecasting take special place. Having wide row of observations there can be possible to reveal some regularity of the phenomena, basing on which, it is possible to proceed forecasting. We looked through many approaches of forecasting that are used in different countries. The analysis of the available work has allowed to draw up a conclusion that while referring to the question of landslide forecasting, it is necessary to approach in system form, taking into account interacting components of the nature. The study of landslide processes has shown that these processes lies within the framework of engineering-geological directions of the science and also interacts with tectonics, geomorphology, hydrogeology, hydrology, climate change, technogenesis and etc. Thereby, the necessity of system approach, achievements of modern science and technology the most expedient approach to make a decision at landslide forecasting is probabilistic-statistical method with complex use of geological and satellite data, specific images processed through geoinformation systems. In this connection, probabilistic-statistical approach, reflecting natural characteristics of interacting natural system, allows to take into account multi-factored processes of landslide activations. Among the many factors, influencing on landslide activation, there exist ones that are not amenable to numerical feature. The parameters of these factors have descriptive, qualitative, rather than quantitative nature. Leaving these factors with lack of attention is absolutely not reasonable. Proposed approach has one more advantage, which allows taking into account not only numerical, but also non-numeric parameters. Combination of multidisciplinary, systematic feature, multifactorness of the account, probabilistic and statistical methods of the calculation, complex use of geological and satellite data, using modern technology processing and analysis of information - all these aspects were collected in one at proposed by authors approach to solve the question of defining the area of possible landslide activation. Proposed by authors method could be a part of the monitoring system for early warning of landslide activation. Thus, the authors propose to initialize the project “System development over the monitoring for the purpose of early warning of population from the threat of landslides”. In the process of project implementation there to be revealed such results like: 1. System of Geo-indicators in order to early warn quick-running landslide processes. 2. United interconnected system for remote, surface and underground types of observations over Geo-indicators. 3. Notification system of population about forthcoming threat by means of alerts, light signals, mobilization of municipalities and related ministries. In the result of project implementation there considered to reveal economic, technical, and social outputs.

Probabilistic Material Strength Degradation Model for Inconel 718 Components Subjected to High Temperature, Mechanical Fatigue, Creep and Thermal Fatigue Effects

NASA Technical Reports Server (NTRS)

Bast, Callie Corinne Scheidt

1994-01-01

This thesis presents the on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes four effects that typically reduce lifetime strength: high temperature, mechanical fatigue, creep, and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for four variables, namely, high temperature, mechanical fatigue, creep, and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using the current version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of mechanical fatigue, creep, and thermal fatigue was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.

The Correlation between Leadership Style and Leader Power

DTIC Science & Technology

2016-04-22

Article 3. DATES COVERED (From - To) 1 February 2015-31 October 2015 4. TITLE AND SUBTITLE The Correlation between Leadership Style and Leader Power...Transformational and Transactional leadership style and leader power. Leadership style was measured by the Multifactor Leadership Questionnaire (MLQ...between the factors representing Leadership Style and Leader Power. The CFA results are contrary to developer’s theories of both scales, but are

The Development of a Tactical-Level Full Range Leadership Measurement Instrument

DTIC Science & Technology

2010-03-01

full range leadership theory has become established as the predominant and most widely researched theory on leadership . The most commonly used survey...instrument to assess full range leadership theory is the Multifactor Leadership Questionnaire, originally developed by Bass in 1985. Although much...existing literature to develop a new full range leadership theory measurement instrument that effectively targets low- to mid-level supervisors, or

Cyclic Load Effects on Long Term Behavior of Polymer Matrix Composites

NASA Technical Reports Server (NTRS)

Shah, A. R.; Chamis, C. C.

1996-01-01

A methodology to compute the fatigue life for different ratios, r, of applied stress to the laminate strength based on first ply failure criteria combined with thermal cyclic loads has been developed and demonstrated. Degradation effects resulting from long term environmental exposure and thermo-mechanical cyclic loads are considered in the simulation process. A unified time-stress dependent multi-factor interaction equation model developed at NASA Lewis Research Center has been used to account for the degradation of material properties caused by cyclic and aging loads. Effect of variation in the thermal cyclic load amplitude on a quasi-symmetric graphite/epoxy laminate has been studied with respect to the impending failure modes. The results show that, for the laminate under consideration, the fatigue life under combined mechanical and low thermal amplitude cyclic loads is higher than that due to mechanical loads only. However, as the thermal amplitude increases, the life also decreases. The failure mode changes from tensile under mechanical loads only to the compressive and shear at high mechanical and thermal loads. Also, implementation of the developed methodology in the design process has been discussed.

Multifactor estimation of ecological risks using numerical simulation

NASA Astrophysics Data System (ADS)

Voskoboynikova, G.; Shalamov, K.; Khairetdinov, M.; Kovalevsky, V.

2017-10-01

In this paper, the problem of interaction of acoustic waves falling at a given angle on a snow layer on the ground and seismic waves arising both in this layer and in the ground is considered. A system of differential equations with boundary conditions describing the propagation of incident and reflected acoustic waves in the air refracted and reflected from the boundary of seismic waves in elastic media (snow and ground) is constructed and solved for a three-layer air-snow layer-ground model. The coefficients of reflection and refraction are calculated in the case of an acoustic wave falling onto both the ground and snow on the ground. The ratio of the energy of the refracted waves to the energy of the falling acoustic wave is obtained. It is noted that snow has a strong influence on the energy transfer into the ground, which can decrease by more than an order of magnitude. The numerical results obtained are consistent with the results of field experiments with a vibrational source performed by the Siberian Branch of the Russian Academy of Sciences.

[Issues of osteoporosis in present-day medicine].

PubMed

Benevolenskaia, L I

2003-01-01

Osteoporosis (OP) is a systemic metabolic lesion of the skeleton involving a reduced osseous tissue weight and an impaired microarchitectonics, which worsens the bone strength and contributes to a higher risk of bone fractures. An essential spread of OP and of osteoporotic fractures among populations in various countries, including Russia, a high-severity outcome, and big economic expenses related with treatment and rehabilitation are indicative of a high social OP significance. OP is a multi-factor pathology provoked by impaired processes in osseous remodeling with a higher resorption of osseous tissue and a reduced osteogenesis. A study of molecular mechanisms of intercellular interaction in OP resulted in discovering new elements in the family of tumor necrosis factor (TNF) and their ligands and receptors (RANKL-RANK-OPG), which are of primary importance in osteoclastogenesis and which are molecular mediators in many regulatory effects. The key drugs applicable to prevention and treatment of OP are also described in the article. The current methods of OP prevention and treatment improve the bone quality and reduce the incidence rate of fracture in an essential share of patients.

A multi-factor Rasch scale for artistic judgment.

PubMed

Bezruczko, Nikolaus

2002-01-01

Measurement properties are reported for a combined scale of abstract and figurative artistic judgment aptitude items. Abstract items are synthetic, rule-based images from Visual Designs Test which implements a statistical algorithm to control design complexity and redundancy, and figurative items are canvas paintings in five styles, Fauvism, Post-Impressionism, Surrealism, Renaissance, and Baroque especially created for this research. The paintings integrate syntactic structure from VDT Abstract designs with thematic content for each style at four levels of complexity while controlling redundancy. Trained test administrators collected preference for synthetic abstract designs and authentic figurative art from 462 examinees in Johnson O'Connor Research Foundation testing offices in Boston, New York, Chicago, and Dallas. The Rasch model replicated measurement properties for VDT Abstract items and identified an item hierarchy that was statistically invariant between genders and generally stable across age for new, authentic figurative items. Further examination of the figurative item hierarchy revealed that complexity interacts with style and meaning. Sound measurement properties for a combined VDT Abstract and Figurative scale shows promise for a comprehensive artistic judgment construct.

Association between oxytocin and receptor genetic polymorphisms and aggression in a northern Chinese Han population with alcohol dependence.

PubMed

Yang, Ling; Wang, Fan; Wang, Meiling; Han, Mei; Hu, Lufeng; Zheng, Minghua; Ma, Ji; Kang, Yimin; Wang, Pengxiang; Sun, Hongqiang; Zuo, Wei; Xie, Longteng; Wang, Aiju; Yu, Dongsheng; Liu, Yanlong

2017-01-01

Alcohol dependence (AD) is a common chronic brain disorder precipitated by complex interactions between biological, genetic, and environmental risk factors. Aggression often occurs in the context of AD. Previous studies have shown that Oxytocin (OXT) and OXT receptor (OXTR) are involved in the regulation of aggression. The present study investigated whether variations and interactions of OXT and OXTR genes were associated with AD-related aggression in a genetically homogeneous northern Chinese Han population. Three hundred and twenty-four male AD patients and 510 male healthy controls (HCs) were recruited. A Chinese version of the Buss-Perry Aggression Questionnaire was used as a subjective measurement of aggressive behavior. Three variations, rs2254298, rs53576, and rs6133010 were genotyped using TaqMan and ligase detection reaction for all subjects. Generalized Multifactor Dimensionality Reduction was used to detect interactions between genetic attributes and environmental attributes. The frequencies of alleles and genotypes of rs6133010 were significantly different between AD patients and HCs (p<0.001). In HCs, the effect of genotype GG of rs53576 on hostility aggression was significantly stronger than that of genotype AA and AG (p=0.001 and p=0.004, respectively), and the subjects with the interaction combination of rs6133010AA×rs2254298GG×rs53576AG exhibited significant effect on physical aggression (p=0.0107). The present study found that rs6133010 in the OXT gene is associated with AD in the northern Chinese Han population. The polymorphisms of OXT/R may play a key role in the susceptibility of AD-related aggression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Impact of interaction between the G870A and EFEMP1 gene polymorphism on glioma risk in Chinese Han population.

PubMed

Yang, Libin; Qu, Bo; Xia, Xun; Kuang, Yongqin; Li, Jian; Fan, Kexia; Guo, Heng; Zheng, Hui; Ma, Yuan

2017-06-06

To investigate the impact of CCND1 and EFEMP1 gene polymorphism, and additional their gene-gene interactions and haplotype within EFEMP1 gene on glioma risk based on Chinese population. Logistic regression was performed to investigate association between single-nucleotide polymorphisms (SNP) and glioma risk and generalized multifactor dimensionality reduction (GMDR) was used to analyze the gene-gene interaction. Glioma risks were higher in carriers of homozygous mutant of rs603965 within CCND1 gene, rs1346787 and rs3791679 in EFEMP1 gene than those with wild-type homozygotes, OR (95%CI) were 1.67 (1.23-2.02), 1.59 (1.25-2.01) and 1.42 (1.15-1.82), respectively. GMDR analysis indicated a significant two-locus model (p=0.0010) involving rs603965 within CCND1 gene and rs1346787 within EFEMP1 gene. Overall, the cross-validation consistency of the two- locus models was 10\\ 10, and the testing accuracy is 60.17%. Participants with rs603965 - GA or AA and rs1346787- AG or GG genotype have the highest glioma risk, compared to participants with rs603965 - GG and rs1346787- AA genotype, OR (95%CI) was 3.65 (1.81-5.22). We conducted haplotype analysis for rs1346787 and rs3791679, because D' value between rs1346787 and rs3791679 was more than 0.8. The most common haplotype was rs1346787 - A and rs3791679- G haplotype, the frequency of which was 0.4905 and 0.4428 in case and control group. Polymorphism in rs603965 within CCND1 gene and rs1346787 within EFEMP1 gene and its gene- gene interaction were associated with increased glioma risk.

Interaction of CARD14, SENP1 and VEGFA polymorphisms on susceptibility to high altitude polycythemia in the Han Chinese population at the Qinghai-Tibetan Plateau.

PubMed

Chen, Yu; Jiang, Chunhua; Luo, Yongjun; Liu, Fuyu; Gao, Yuqi

2016-03-01

High altitude polycythemia (HAPC) is a serious public health problem among Han Chinese immigrants to the Qinghai-Tibetan Plateau. This study aims to explore the genetic basis of HAPC in the Han Chinese population. 484 male subjects (234 patients and 250 controls) were enrolled in this study. Genotyping was performed for polymorphisms of I/D in ACE, C1772T and G1790A in exon 12 of HIF-1α, rs2567206 in CYP1B1, rs726354 in SENP1, rs3025033 in VEGFA, rs7251432 in HAMP, rs2075800 in HSPA1L and rs8065364 in CARD14. Gene-gene interaction was assessed by multifactor dimensionality reduction. A significant association was seen between CARD14 polymorphism rs8065364 and risk of HAPC development in male Han Chinese, and the C allele of rs8065364 was a risk factor (odds ratio (OR)=1.59, 95% confidence interval (95% CI)=1.21-2.08). Gene-gene interaction analysis indicated that a synergistic relationship existed between rs3025033 and rs8065364 (1.00%), rs3025033 and rs726354 (0.18%), and rs726354 and rs8065364 (0.17%). The combination of rs8065364 in CARD14, rs3025033 in VEGFA and rs726354 in SENP1 was the best model to predict HAPC development in this study (testing accuracy=0.6183, p=0.0010, cross-validated consistency=10/10). Genetic interactions of SNPs in CARD14, SENP1 and VEGFA might represent a functional mechanism in the pathogenesis of HAPC. Copyright © 2015 Elsevier Inc. All rights reserved.

Interactions of central obesity with rs3918242 on risk of non-alcoholic fat liver disease: a preliminary case-control study.

PubMed

Wu, Pengbo; Hua, Yonglong; Tan, Shiyun; Li, Ming; Shu, Yongxiang; Fang, Guo

2015-01-01

NAFLD is a complex disease characterized by inflammation and insulin resistance which is determined by an interaction of genetics and environmental factors. MMP gene has been implicated in relation to inflammation and insulin resistance. The preliminary case-control study aimed to investigate the association between Matrix metalloproteinase (MMP)-9-1562C/T (rs3918242), MMP-2-1306C/T (rs243865) and risk of NAFLD and to further evaluate the interactions of central obesity with rs3918242 and rs243865. Two variants, rs3918242 and rs243865, were genotyped by polymerase chain reaction -restriction fragment length polymorphism. Gene-environment interactions on risk of NAFLD was preliminarily investigated by generalized multifactor dimensionality reduction (GMDR) and further confirmed by unconditional logistic regression methods. After adjusting for covariates, increased risk of NAFLD were observed in subjects carrying TT/CT genotypes in rs3918242 ((Adjust)OR=1.64, 95% CI: 1.24, 2.11, P=0.006). However, decreased risk of non-alcoholic fat liver disease was found when MMP-2 rs243865 (TT/CT) genotype carriers compared with CC carrier ((Adjust)OR=0.65, 95% CI: 0.47, 0.72, P=0.000).Interactions of central obesity with rs3918242 was preliminarily found by GMDR, with a maximum prediction accuracy (67.61%) and a maximum Cross-validation Consistency (10/10).The unconditional logistic regression method indicated central obesity-positive subject with genotype TT/CT had 4.54 times risk of NAFLD compared to central obesity-negative subjects with genotype CC (OR(add)(a)=4.54, 95% CI: 2.81, 7.21, P(add)(a)=0.000), which further confirmed the interactions. The results indicate that both rs3918242 and rs243865 is associated with risk of NAFLD. Furthermore, rs3918242 and central obesity have synergistic effects on risk of NAFLD.

Light-Induced Changes of the Circadian Clock of Humans: Increasing Duration is More Effective than Increasing Light Intensity

PubMed Central

Dewan, Karuna; Benloucif, Susan; Reid, Kathryn; Wolfe, Lisa F.; Zee, Phyllis C.

2011-01-01

Study Objectives: To evaluate the effect of increasing the intensity and/or duration of exposure on light-induced changes in the timing of the circadian clock of humans. Design: Multifactorial randomized controlled trial, between and within subject design Setting: General Clinical Research Center (GCRC) of an academic medical center Participants: 56 healthy young subjects (20-40 years of age) Interventions: Research subjects were admitted for 2 independent stays of 4 nights/3 days for treatment with bright or dim-light (randomized order) at a time known to induce phase delays in circadian timing. The intensity and duration of the bright light were determined by random assignment to one of 9 treatment conditions (duration of 1, 2, or 3 hours at 2000, 4000, or 8000 lux). Measurements and Results: Treatment-induced changes in the dim light melatonin onset (DLMO) and dim light melatonin offset (DLMOff) were measured from blood samples collected every 20-30 min throughout baseline and post-treatment nights. Comparison by multi-factor analysis of variance (ANOVA) of light-induced changes in the time of the circadian melatonin rhythm for the 9 conditions revealed that changing the duration of the light exposure from 1 to 3 h increased the magnitude of light-induced delays. In contrast, increasing from moderate (2,000 lux) to high (8,000 lux) intensity light did not alter the magnitude of phase delays of the circadian melatonin rhythm. Conclusions: Results from the present study suggest that for phototherapy of circadian rhythm sleep disorders in humans, a longer period of moderate intensity light may be more effective than a shorter exposure period of high intensity light. Citation: Dewan K; Benloucif S; Reid K; Wolfe LF; Zee PC. Light-induced changes of the circadian clock of humans: increasing duration is more effective than increasing light intensity. SLEEP 2011;34(5):593-599. PMID:21532952

Modern methods for the quality management of high-rate melt solidification

NASA Astrophysics Data System (ADS)

Vasiliev, V. A.; Odinokov, S. A.; Serov, M. M.

2016-12-01

The quality management of high-rate melt solidification needs combined solution obtained by methods and approaches adapted to a certain situation. Technological audit is recommended to estimate the possibilities of the process. Statistical methods are proposed with the choice of key parameters. Numerical methods, which can be used to perform simulation under multifactor technological conditions, and an increase in the quality of decisions are of particular importance.

An Evaluation of the Relationship between Supervisory Techniques and Organizational Outcomes among the Supervisors in the Agricultural Extension Service in the Eastern Region Districts of Uganda. Summary of Research 81.

ERIC Educational Resources Information Center

Padde, Paul; And Others

A descriptive study examined the relationship between supervisory techniques and organizational outcomes among supervisors in the agricultural extension service in eight districts in eastern Uganda. Self-rating and rater forms of the Multifactor Leadership Questionnaire were sent to 220 extension agents, 8 field supervisors, and 8 deputy field…

Jackknife for Variance Analysis of Multifactor Experiments.

DTIC Science & Technology

1982-05-01

variance-covariance matrix is generated y a subroutine named CORAN (UNIVAC, 1969). The jackknife variances are then punched on computer cards in the same...LEVEL OF: InMte CALL cORAN (oaILa.NSUR.NOAY.D,*OXflRRORR.PCOF.2K.1’)I WRITE IP97111 )1RRN.4 .1:NDAY) 0 a 3fill1UR I .’t UN 001f’..1uŔ:1 .w100710n

Long-duration effect of multi-factor stresses on the cellular biochemistry, oil-yielding performance and morphology of Nannochloropsis oculata

PubMed Central

Wei, Likun; Huang, Xuxiong

2017-01-01

Microalga Nannochloropsis oculata is a promising alternative feedstock for biodiesel. Elevating its oil-yielding capacity is conducive to cost-saving biodiesel production. However, the regulatory processes of multi-factor collaborative stresses (MFCS) on the oil-yielding performance of N. oculata are unclear. The duration effects of MFCS (high irradiation, nitrogen deficiency and elevated iron supplementation) on N. oculata were investigated in an 18-d batch culture. Despite the reduction in cell division, the biomass concentration increased, resulting from the large accumulation of the carbon/energy-reservoir. However, different storage forms were found in different cellular storage compounds, and both the protein content and pigment composition swiftly and drastically changed. The analysis of four biodiesel properties using pertinent empirical equations indicated their progressive effective improvement in lipid classes and fatty acid composition. The variation curve of neutral lipid productivity was monitored with fluorescent Nile red and was closely correlated to the results from conventional methods. In addition, a series of changes in the organelles (e.g., chloroplast, lipid body and vacuole) and cell shape, dependent on the stress duration, were observed by TEM and LSCM. These changes presumably played an important role in the acclimation of N. oculata to MFCS and accordingly improved its oil-yielding performance. PMID:28346505

Multilevel Factorial Experiments for Developing Behavioral Interventions: Power, Sample Size, and Resource Considerations†

PubMed Central

Dziak, John J.; Nahum-Shani, Inbal; Collins, Linda M.

2012-01-01

Factorial experimental designs have many potential advantages for behavioral scientists. For example, such designs may be useful in building more potent interventions, by helping investigators to screen several candidate intervention components simultaneously and decide which are likely to offer greater benefit before evaluating the intervention as a whole. However, sample size and power considerations may challenge investigators attempting to apply such designs, especially when the population of interest is multilevel (e.g., when students are nested within schools, or employees within organizations). In this article we examine the feasibility of factorial experimental designs with multiple factors in a multilevel, clustered setting (i.e., of multilevel multifactor experiments). We conduct Monte Carlo simulations to demonstrate how design elements such as the number of clusters, the number of lower-level units, and the intraclass correlation affect power. Our results suggest that multilevel, multifactor experiments are feasible for factor-screening purposes, because of the economical properties of complete and fractional factorial experimental designs. We also discuss resources for sample size planning and power estimation for multilevel factorial experiments. These results are discussed from a resource management perspective, in which the goal is to choose a design that maximizes the scientific benefit using the resources available for an investigation. PMID:22309956

Cardiovascular disease prevention and lifestyle interventions: effectiveness and efficacy.

PubMed

Haskell, William L

2003-01-01

Over the past half century scientific data support the strong relationship between the way a person or population lives and their risk for developing or dying from cardiovascular disease (CVD). While heredity can be a major factor for some people, their personal health habits and environmental/cultural exposure are more important factors. CVD is a multifactor process that is contributed to by a variety of biological and behavioral characteristics of the person including a number of well-established and emerging risk factors. Not smoking, being physically active, eating a heart healthy diet, staying reasonably lean, and avoiding major stress and depression are the major components of an effective CVD prevention program. For people at high risk of CVD, medications frequently need to be added to a healthy lifestyle to minimize their risk of a heart attack or stroke, particularly in persons with conditions such as hypertension, hypercholesterolemia, or hyperglycemia. Maintaining an effective CVD prevention program in technologically advanced societies cannot be achieved by many high-risk persons without effective and sustained support from a well-organized health care system. Nurse-provided or nurse-coordinated care management programs using an integrated or multifactor approach have been highly effective in reducing CVD morbidity and mortality of high-risk persons.

Multifactor leadership styles and new exposure to workplace bullying: a six-month prospective study

PubMed Central

TSUNO, Kanami; KAWAKAMI, Norito

2014-01-01

This study investigated the prospective association between supervisor leadership styles and workplace bullying. Altogether 404 civil servants from a local government in Japan completed baseline and follow-up surveys. The leadership variables and exposure to bullying were measured by Multifactor Leadership Questionnaire and Negative Acts Questionnaire-Revised, respectively. The prevalence of workplace bullying was 14.8% at baseline and 15.1% at follow-up. Among respondents who did not experience bullying at baseline (n=216), those who worked under the supervisors as higher in passive laissez-faire leadership had a 4.3 times higher risk of new exposure to bullying. On the other hand, respondents whose supervisors with highly considerate of the individual had a 70% lower risk of new exposure to bullying. In the entire sample (n=317), passive laissez-faire leadership was significantly and positively associated, while charisma/inspiration, individual consideration, and contingent reward were negatively associated both after adjusting for demographic and occupational characteristics at baseline, life events during follow-up, and exposure to workplace bullying at baseline. Results indicated that passive laissez-faire and low individual consideration leadership style at baseline were strong predictors of new exposure to bullying and high individual consideration leadership of supervisors/managers could be a preventive factor against bullying. PMID:25382384

Multifactor leadership styles and new exposure to workplace bullying: a six-month prospective study.

PubMed

Tsuno, Kanami; Kawakami, Norito

2015-01-01

This study investigated the prospective association between supervisor leadership styles and workplace bullying. Altogether 404 civil servants from a local government in Japan completed baseline and follow-up surveys. The leadership variables and exposure to bullying were measured by Multifactor Leadership Questionnaire and Negative Acts Questionnaire-Revised, respectively. The prevalence of workplace bullying was 14.8% at baseline and 15.1% at follow-up. Among respondents who did not experience bullying at baseline (n=216), those who worked under the supervisors as higher in passive laissez-faire leadership had a 4.3 times higher risk of new exposure to bullying. On the other hand, respondents whose supervisors with highly considerate of the individual had a 70% lower risk of new exposure to bullying. In the entire sample (n=317), passive laissez-faire leadership was significantly and positively associated, while charisma/inspiration, individual consideration, and contingent reward were negatively associated both after adjusting for demographic and occupational characteristics at baseline, life events during follow-up, and exposure to workplace bullying at baseline. Results indicated that passive laissez-faire and low individual consideration leadership style at baseline were strong predictors of new exposure to bullying and high individual consideration leadership of supervisors/managers could be a preventive factor against bullying.

Application of an Instrumental and Computational Approach for Improving the Vibration Behavior of Structural Panels Using a Lightweight Multilayer Composite

PubMed Central

Sánchez, Alberto; García, Manuel; Sebastián, Miguel Angel; Camacho, Ana María

2014-01-01

This work presents a hybrid (experimental-computational) application for improving the vibration behavior of structural components using a lightweight multilayer composite. The vibration behavior of a flat steel plate has been improved by the gluing of a lightweight composite formed by a core of polyurethane foam and two paper mats placed on its faces. This composite enables the natural frequencies to be increased and the modal density of the plate to be reduced, moving about the natural frequencies of the plate out of excitation range, thereby improving the vibration behavior of the plate. A specific experimental model for measuring the Operating Deflection Shape (ODS) has been developed, which enables an evaluation of the goodness of the natural frequencies obtained with the computational model simulated by the finite element method (FEM). The model of composite + flat steel plate determined by FEM was used to conduct parametric study, and the most influential factors for 1st, 2nd and 3rd mode were identified using a multifactor analysis of variance (Multifactor-ANOVA). The presented results can be easily particularized for other cases, as it may be used in cycles of continuous improvement as well as in the product development at the material, piece, and complete-system levels. PMID:24618779

Multilevel factorial experiments for developing behavioral interventions: power, sample size, and resource considerations.

PubMed

Dziak, John J; Nahum-Shani, Inbal; Collins, Linda M

2012-06-01

Factorial experimental designs have many potential advantages for behavioral scientists. For example, such designs may be useful in building more potent interventions by helping investigators to screen several candidate intervention components simultaneously and to decide which are likely to offer greater benefit before evaluating the intervention as a whole. However, sample size and power considerations may challenge investigators attempting to apply such designs, especially when the population of interest is multilevel (e.g., when students are nested within schools, or when employees are nested within organizations). In this article, we examine the feasibility of factorial experimental designs with multiple factors in a multilevel, clustered setting (i.e., of multilevel, multifactor experiments). We conduct Monte Carlo simulations to demonstrate how design elements-such as the number of clusters, the number of lower-level units, and the intraclass correlation-affect power. Our results suggest that multilevel, multifactor experiments are feasible for factor-screening purposes because of the economical properties of complete and fractional factorial experimental designs. We also discuss resources for sample size planning and power estimation for multilevel factorial experiments. These results are discussed from a resource management perspective, in which the goal is to choose a design that maximizes the scientific benefit using the resources available for an investigation. (c) 2012 APA, all rights reserved

Association between adiponectin polymorphisms and the risk of colorectal cancer.

PubMed

Guo, Xin; Liu, Jiaqi; You, Liuping; Li, Gang; Huang, Yuenan; Li, Yunlong

2015-01-01

To discuss the association between adiponectin (ADIPOQ) gene rs2241766 and rs1501299 polymorphisms and the risk of colorectal cancer, and to analyze the role of the interaction between these two loci and environmental factors in colorectal cancer pathogenesis. The case-control study was performed with a 1:1 match. A self-designed questionnaire was used to perform a face-to-face survey with 600 new primary colorectal cancer cases confirmed by histopathology as well as 600 cases of people receiving a physical examination at the same time. The general information, lifestyle, and diet habits, etc. were collected from two groups of study subjects. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to identify ADIPOQ rs2241766 and rs1501299 genotypes. After adjusting for factors such as colorectal cancer family history, body-mass index (BMI), daily sedentary time, weekly red meat intake frequency, as well regular tea drinking, conditional logistic regression analysis indicated that rs2241766 TG+GG carriers had a higher risk of colorectal cancer than TT carriers (OR=1.433, 95% CI: 1.014-1.985); rs1501299 GT+TT carriers had a lower risk of colorectal cancer than GG carriers (OR=0.723, 95% CI: 0.531-0.902). Generalized multifactor dimensionality reduction analysis showed that ADIPOQ rs2241766 and rs1501299 could have interaction with red meat intake (p=0.001). ADIPOQ rs2241766 and rs1501299 single nucleotide polymorphisms (SNPs) could be associated with colorectal pathogenesis and could have interactions with red meat intake. Both factors impact colorectal cancer occurrence.

Warming Rather Than Increased Precipitation Increases Soil Recalcitrant Organic Carbon in a Semiarid Grassland after 6 Years of Treatments

PubMed Central

Zhou, Xiaoqi; Chen, Chengrong; Wang, Yanfen; Smaill, Simeon; Clinton, Peter

2013-01-01

Improved understanding of changes in soil recalcitrant organic carbon (C) in response to global warming is critical for predicting changes in soil organic C (SOC) storage. Here, we took advantage of a long-term field experiment with increased temperature and precipitation to investigate the effects of warming, increased precipitation and their interactions on SOC fraction in a semiarid Inner Mongolian grassland of northern China since April 2005. We quantified labile SOC, recalcitrant SOC and stable SOC at 0–10 and 10–20 cm depths. Results showed that neither warming nor increased precipitation affected total SOC and stable SOC at either depth. Increased precipitation significantly increased labile SOC at the 0–10 cm depth. Warming decreased labile SOC (P = 0.038) and marginally but significantly increased recalcitrant SOC at the 10–20 cm depth (P = 0.082). In addition, there were significant interactive effects of warming and increased precipitation on labile SOC and recalcitrant SOC at the 0–10 cm depth (both P<0.05), indicating that that results from single factor experiments should be treated with caution because of multi-factor interactions. Given that the absolute increase of SOC in the recalcitrant SOC pool was much greater than the decrease in labile SOC, and that the mean residence time of recalcitrant SOC is much greater, our results suggest that soil C storage at 10–20 cm depth may increase with increasing temperature in this semiarid grassland. PMID:23341995

Nurse executive transformational leadership found in participative organizations.

PubMed

Dunham-Taylor, J

2000-05-01

The study examined a national sample of 396 randomly selected hospital nurse executives to explore transformational leadership, stage of power, and organizational climate. Results from a few nurse executive studies have found nurse executives were transformational leaders. As executives were more transformational, they achieved better staff satisfaction and higher work group effectiveness. This study integrates Bass' transformational leadership model with Hagberg's power stage theory and Likert's organizational climate theory. Nurse executives (396) and staff reporting to them (1,115) rated the nurse executives' leadership style, staff extra effort, staff satisfaction, and work group effectiveness using Bass and Avolio's Multifactor Leadership Questionnaire. Executives' bosses (360) rated executive work group effectiveness. Executives completed Hagberg's Personal Power Profile and ranked their organizational climate using Likert's Profile of Organizational Characteristics. Nurse executives used transformational leadership fairly often; achieved fairly satisfied staff levels; were very effective according to bosses; were most likely at stage 3 (power by achievement) or stage 4 (power by reflection); and rated their hospital as a Likert System 3 Consultative Organization. Staff satisfaction and work group effectiveness decreased as nurse executives were more transactional. Higher transformational scores tended to occur with higher educational degrees and within more participative organizations. Transformational qualities can be enhanced by further education, by achieving higher power stages, and by being within more participative organizations.

Predictive models of poly(ethylene-terephthalate) film degradation under multi-factor accelerated weathering exposures

PubMed Central

Ngendahimana, David K.; Fagerholm, Cara L.; Sun, Jiayang; Bruckman, Laura S.

2017-01-01

Accelerated weathering exposures were performed on poly(ethylene-terephthalate) (PET) films. Longitudinal multi-level predictive models as a function of PET grades and exposure types were developed for the change in yellowness index (YI) and haze (%). Exposures with similar change in YI were modeled using a linear fixed-effects modeling approach. Due to the complex nature of haze formation, measurement uncertainty, and the differences in the samples’ responses, the change in haze (%) depended on individual samples’ responses and a linear mixed-effects modeling approach was used. When compared to fixed-effects models, the addition of random effects in the haze formation models significantly increased the variance explained. For both modeling approaches, diagnostic plots confirmed independence and homogeneity with normally distributed residual errors. Predictive R2 values for true prediction error and predictive power of the models demonstrated that the models were not subject to over-fitting. These models enable prediction under pre-defined exposure conditions for a given exposure time (or photo-dosage in case of UV light exposure). PET degradation under cyclic exposures combining UV light and condensing humidity is caused by photolytic and hydrolytic mechanisms causing yellowing and haze formation. Quantitative knowledge of these degradation pathways enable cross-correlation of these lab-based exposures with real-world conditions for service life prediction. PMID:28498875

A remote sensing-assisted risk rating study to predict oak decline and recovery in the Missouri Ozark Highlands, USA

Treesearch

Cuizhen Wang; Hong S. He; John M. Kabrick

2008-01-01

Forests in the Ozark Highlands underwent widespread oak decline affected by severe droughts in 1999-2000. In this study, the differential normalized difference water index was calculated to detect crown dieback. A multi-factor risk rating system was built to map risk levels of stands. As a quick response to drought, decline in 2000 mostly occurred in stands at low to...

Do little interactions get lost in dark random forests?

PubMed

Wright, Marvin N; Ziegler, Andreas; König, Inke R

2016-03-31

Random forests have often been claimed to uncover interaction effects. However, if and how interaction effects can be differentiated from marginal effects remains unclear. In extensive simulation studies, we investigate whether random forest variable importance measures capture or detect gene-gene interactions. With capturing interactions, we define the ability to identify a variable that acts through an interaction with another one, while detection is the ability to identify an interaction effect as such. Of the single importance measures, the Gini importance captured interaction effects in most of the simulated scenarios, however, they were masked by marginal effects in other variables. With the permutation importance, the proportion of captured interactions was lower in all cases. Pairwise importance measures performed about equal, with a slight advantage for the joint variable importance method. However, the overall fraction of detected interactions was low. In almost all scenarios the detection fraction in a model with only marginal effects was larger than in a model with an interaction effect only. Random forests are generally capable of capturing gene-gene interactions, but current variable importance measures are unable to detect them as interactions. In most of the cases, interactions are masked by marginal effects and interactions cannot be differentiated from marginal effects. Consequently, caution is warranted when claiming that random forests uncover interactions.

Climate change impacts: The challenge of quantifying multi-factor causation, multi-component responses, and leveraging from extremes

NASA Astrophysics Data System (ADS)

Field, C. B.

2012-12-01

Modeling climate change impacts is challenging for a variety of reasons. Some of these are related to causation. A weather or climate event is rarely the sole cause of an impact, and, for many impacts, social, economic, cultural, or ecological factors may play a larger role than climate. Other challenges are related to outcomes. Consequences of an event are often most severe when several kinds of responses interact, typically in unexpected ways. Many kinds of consequences are difficult to quantify, especially when they include a mix of market, cultural, personal, and ecological values. In addition, scale can be tremendously important. Modest impacts over large areas present very different challenges than severe but very local impacts. Finally, impacts may respond non-linearly to forcing, with behavior that changes qualitatively at one or more thresholds and with unexpected outcomes in extremes. Modeling these potentially complex interactions between drivers and impacts presents one set of challenges. Evaluating the models presents another. At least five kinds of approaches can contribute to the evaluation of impact models designed to provide insights in multi-driver, multi-responder, multi-scale, and extreme-driven contexts, even though none of these approaches is a complete or "silver-bullet" solution. The starting point for much of the evaluation in this space is case studies. Case studies can help illustrate links between processes and scales. They can highlight factors that amplify or suppress sensitivity to climate drivers, and they can suggest the consequences of intervening at different points. While case studies rarely provide concrete evidence about mechanisms, they can help move a mechanistic case from circumstantial to sound. Novel approaches to data collection, including crowd sourcing, can potentially provide tools and the number of relevant examples to develop case studies as statistically robust data sources. A critical condition for progress in this area is the ability to utilize data of uneven quality and standards. Novel approaches to meta-analysis provide other options for taking advantage of diverse case studies. Techniques for summarizing responses across impacts, drivers, and scales can play a huge role in increasing the value of information from case studies. In some cases, expert elicitation may provide alternatives for identifying mechanisms or for interpreting multi-factor drivers or responses. Especially when designed to focus on a well-defined set of observations, a sophisticated elicitation can establish formal confidence limits on responses that are otherwise difficult to constrain. A final possible approach involves a focus on the mechanisms contributing to an impact, rather than the impact itself. Approaches based on quantified mechanisms are especially appealing in the context of models where the number of interactions makes it difficult to intuitively understand the chain of connections from cause to effect, when actors differ in goals or sensitivities, or when scale affects parts of the system differently. With all of these approaches, useful evidence may not conform to traditional levels of statistical confidence. Some of the biggest challenges in taking advantage of the potential tools will involve defining what constitutes a meaningful evaluation.

Case management to reduce risk of cardiovascular disease in a county health care system.

PubMed

Ma, Jun; Berra, Kathy; Haskell, William L; Klieman, Linda; Hyde, Shauna; Smith, Mark W; Xiao, Lan; Stafford, Randall S

2009-11-23

Case management (CM) is a systematic approach to supplement physician-centered efforts to prevent cardiovascular disease (CVD). Research is limited on its implementation and efficacy in low-income, ethnic minority populations. We conducted a randomized clinical trial to evaluate a nurse- and dietitian-led CM program for reducing major CVD risk factors in low-income, primarily ethnic minority patients in a county health care system, 63.0% of whom had type 2 diabetes mellitus. The primary outcome was the Framingham risk score (FRS). A total of 419 patients at elevated risk of CVD events were randomized and followed up for a mean of 16 months (81.4% retention). The mean FRS was significantly lower for the CM vs usual care group at follow-up (7.80 [95% confidence interval, 7.21-8.38] vs 8.93 [8.36-9.49]; P = .001) after adjusting for baseline FRS. This is equivalent to 5 fewer heart disease events per 1000 individuals per year attributable to the intervention or to 200 individuals receiving the intervention to prevent 1 event per year. The pattern of group differences in the FRS was similar in subgroups defined a priori by sex and ethnicity. The main driver of these differences was lowering the mean (SD) systolic (-4.2 [18.5] vs 2.6 [22.7] mm Hg; P = .003) and diastolic (-6.0 [11.6] vs -3.0 [11.7] mm Hg; P = .02) blood pressures for the CM vs usual care group. Nurse and dietitian CM targeting multifactor risk reduction can lead to modest improvements in CVD risk factors among high-risk patients in low-income, ethnic minority populations receiving care in county health clinics. clinicaltrials.gov Identifier: NCT00128687.

dLocAuth: a dynamic multifactor authentication scheme for mCommerce applications using independent location-based obfuscation

NASA Astrophysics Data System (ADS)

Kuseler, Torben; Lami, Ihsan A.

2012-06-01

This paper proposes a new technique to obfuscate an authentication-challenge program (named LocProg) using randomly generated data together with a client's current location in real-time. LocProg can be used to enable any handsetapplication on mobile-devices (e.g. mCommerce on Smartphones) that requires authentication with a remote authenticator (e.g. bank). The motivation of this novel technique is to a) enhance the security against replay attacks, which is currently based on using real-time nonce(s), and b) add a new security factor, which is location verified by two independent sources, to challenge / response methods for authentication. To assure a secure-live transaction, thus reducing the possibility of replay and other remote attacks, the authors have devised a novel technique to obtain the client's location from two independent sources of GPS on the client's side and the cellular network on authenticator's side. The algorithm of LocProg is based on obfuscating "random elements plus a client's data" with a location-based key, generated on the bank side. LocProg is then sent to the client and is designed so it will automatically integrate into the target application on the client's handset. The client can then de-obfuscate LocProg if s/he is within a certain range around the location calculated by the bank and if the correct personal data is supplied. LocProg also has features to protect against trial/error attacks. Analysis of LocAuth's security (trust, threat and system models) and trials based on a prototype implementation (on Android platform) prove the viability and novelty of LocAuth.

Press-pulse interactions: effects of warming, N deposition, altered winter precipitation, and fire on desert grassland community structure and dynamics.

PubMed

Collins, Scott L; Ladwig, Laura M; Petrie, Matthew D; Jones, Sydney K; Mulhouse, John M; Thibault, James R; Pockman, William T

2017-03-01

Global environmental change is altering temperature, precipitation patterns, resource availability, and disturbance regimes. Theory predicts that ecological presses will interact with pulse events to alter ecosystem structure and function. In 2006, we established a long-term, multifactor global change experiment to determine the interactive effects of nighttime warming, increased atmospheric nitrogen (N) deposition, and increased winter precipitation on plant community structure and aboveground net primary production (ANPP) in a northern Chihuahuan Desert grassland. In 2009, a lightning-caused wildfire burned through the experiment. Here, we report on the interactive effects of these global change drivers on pre- and postfire grassland community structure and ANPP. Our nighttime warming treatment increased winter nighttime air temperatures by an average of 1.1 °C and summer nighttime air temperature by 1.5 °C. Soil N availability was 2.5 times higher in fertilized compared with control plots. Average soil volumetric water content (VWC) in winter was slightly but significantly higher (13.0% vs. 11.0%) in plots receiving added winter rain relative to controls, and VWC was slightly higher in warmed (14.5%) compared with control (13.5%) plots during the growing season even though surface soil temperatures were significantly higher in warmed plots. Despite these significant treatment effects, ANPP and plant community structure were highly resistant to these global change drivers prior to the fire. Burning reduced the cover of the dominant grasses by more than 75%. Following the fire, forb species richness and biomass increased significantly, particularly in warmed, fertilized plots that received additional winter precipitation. Thus, although unburned grassland showed little initial response to multiple ecological presses, our results demonstrate how a single pulse disturbance can interact with chronic alterations in resource availability to increase ecosystem sensitivity to multiple drivers of global environmental change. © 2016 John Wiley & Sons Ltd.

Multilocus analyses of seven candidate genes suggest interacting pathways for obesity-related traits in Brazilian populations.

PubMed

Angeli, Cláudia B; Kimura, Lilian; Auricchio, Maria T; Vicente, João P; Mattevi, Vanessa S; Zembrzuski, Verônica M; Hutz, Mara H; Pereira, Alexandre C; Pereira, Tiago V; Mingroni-Netto, Regina C

2011-06-01

We investigated whether variants in major candidate genes for food intake and body weight regulation contribute to obesity-related traits under a multilocus perspective. We studied 375 Brazilian subjects from partially isolated African-derived populations (quilombos). Seven variants displaying conflicting results in previous reports and supposedly implicated in the susceptibility of obesity-related phenotypes were investigated: β2-adrenergic receptor (ADRB2) (Arg16Gly), insulin induced gene 2 (INSIG2) (rs7566605), leptin (LEP) (A19G), LEP receptor (LEPR) (Gln223Arg), perilipin (PLIN) (6209T > C), peroxisome proliferator-activated receptor-γ (PPARG) (Pro12Ala), and resistin (RETN) (-420 C > G). Regression models as well as generalized multifactor dimensionality reduction (GMDR) were employed to test the contribution of individual effects and higher-order interactions to BMI and waist-hip ratio (WHR) variation and risk of overweight/obesity. The best multilocus association signal identified in the quilombos was further examined in an independent sample of 334 Brazilian subjects of European ancestry. In quilombos, only the PPARG polymorphism displayed significant individual effects (WHR variation, P = 0.028). No association was observed either with the risk of overweight/obesity (BMI ≥ 25 kg/m2), risk of obesity alone (BMI ≥ 30 kg/m2) or BMI variation. However, GMDR analyses revealed an interaction between the LEPR and ADRB2 polymorphisms (P = 0.009) as well as a third-order effect involving the latter two variants plus INSIG2 (P = 0.034) with overweight/obesity. Assessment of the LEPR-ADRB2 interaction in the second sample indicated a marginally significant association (P = 0.0724), which was further verified to be limited to men (P = 0.0118). Together, our findings suggest evidence for a two-locus interaction between the LEPR Gln223Arg and ADRB2 Arg16Gly variants in the risk of overweight/obesity, and highlight further the importance of multilocus effects in the genetic component of obesity.

Implicit prosody mining based on the human eye image capture technology

NASA Astrophysics Data System (ADS)

Gao, Pei-pei; Liu, Feng

2013-08-01

The technology of eye tracker has become the main methods of analyzing the recognition issues in human-computer interaction. Human eye image capture is the key problem of the eye tracking. Based on further research, a new human-computer interaction method introduced to enrich the form of speech synthetic. We propose a method of Implicit Prosody mining based on the human eye image capture technology to extract the parameters from the image of human eyes when reading, control and drive prosody generation in speech synthesis, and establish prosodic model with high simulation accuracy. Duration model is key issues for prosody generation. For the duration model, this paper put forward a new idea for obtaining gaze duration of eyes when reading based on the eye image capture technology, and synchronous controlling this duration and pronunciation duration in speech synthesis. The movement of human eyes during reading is a comprehensive multi-factor interactive process, such as gaze, twitching and backsight. Therefore, how to extract the appropriate information from the image of human eyes need to be considered and the gaze regularity of eyes need to be obtained as references of modeling. Based on the analysis of current three kinds of eye movement control model and the characteristics of the Implicit Prosody reading, relative independence between speech processing system of text and eye movement control system was discussed. It was proved that under the same text familiarity condition, gaze duration of eyes when reading and internal voice pronunciation duration are synchronous. The eye gaze duration model based on the Chinese language level prosodic structure was presented to change previous methods of machine learning and probability forecasting, obtain readers' real internal reading rhythm and to synthesize voice with personalized rhythm. This research will enrich human-computer interactive form, and will be practical significance and application prospect in terms of disabled assisted speech interaction. Experiments show that Implicit Prosody mining based on the human eye image capture technology makes the synthesized speech has more flexible expressions.

The impact of high total cholesterol and high low-density lipoprotein on avascular necrosis of the femoral head in low-energy femoral neck fractures.

PubMed

Zeng, Xianshang; Zhan, Ke; Zhang, Lili; Zeng, Dan; Yu, Weiguang; Zhang, Xinchao; Zhao, Mingdong; Lai, Zhicheng; Chen, Runzhen

2017-02-17

Avascular necrosis of the femoral head (AVNFH) typically constitutes 5 to 15% of all complications of low-energy femoral neck fractures, and due to an increasingly ageing population and a rising prevalence of femoral neck fractures, the number of patients who develop AVNFH is increasing. However, there is no consensus regarding the relationship between blood lipid abnormalities and postoperative AVNFH. The purpose of this retrospective study was to investigate the relationship between blood lipid abnormalities and AVNFH following the femoral neck fracture operation among an elderly population. A retrospective, comparative study was performed at our institution. Between June 2005 and November 2009, 653 elderly patients (653 hips) with low-energy femoral neck fractures underwent closed reduction and internal fixation with cancellous screws (Smith and Nephew, Memphis, Tennessee). Follow-up occurred at 1, 6, 12, 18, 24, 30, and 36 months after surgery. Logistic multi-factor regression analysis was used to assess the risk factors of AVNFH and to determine the effect of blood lipid levels on AVNFH development. Inclusion and exclusion criteria were predetermined to focus on isolated freshly closed femoral neck fractures in the elderly population. The primary outcome was the blood lipid levels. The secondary outcome was the logistic multi-factor regression analysis. A total of 325 elderly patients with low-energy femoral neck fractures (AVNFH, n = 160; control, n = 165) were assessed. In the AVNFH group, the average TC, TG, LDL, and Apo-B values were 7.11 ± 3.16 mmol/L, 2.15 ± 0.89 mmol/L, 4.49 ± 1.38 mmol/L, and 79.69 ± 17.29 mg/dL, respectively; all of which were significantly higher than the values in the control group. Logistic multi-factor regression analysis showed that both TC and LDL were the independent factors influencing the postoperative AVNFH within femoral neck fractures. This evidence indicates that AVNFH was significantly associated with blood lipid abnormalities in elderly patients with low-energy femoral neck fractures. The findings of this pilot trial justify a larger study to determine whether the result is more generally applicable to a broader population.

An Economical Multifactor within-Subject Design Robust against Trend and Carryover Effects.

DTIC Science & Technology

1985-10-17

ORGANIZATION REPORT NUMBER (S) S. MONIT ,,M.,,...---. 6a. NAME OF PERFORMING ORGANIZATION 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION Essex...Road Orlando, FL 32813 Orlando, FL 32803 Ba. NAME OF FUNDING/SPONSORING " Sb. OFFICE SYMBOL 9. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ...ORGANIZATION (If applicable) S6~1332- &/. 0.-/195𔃺 Sc. ADDRESS (City, State, and ZIP Code) 10. SOURCE OF FUNDING NUMBERS PROGRAM PROJECT TASK WORK UNIT ELEMENT

[Chemical and sensory characterization of tea (Thea sinensis) consumed in Chile].

PubMed

Wittig de Penna, Emma; José Zúñiga, María; Fuenzalida, Regina; López-Planes, Reinaldo

2005-03-01

By means of descriptive analysis four varieties of tea (Thea sinensis) were assesed: Argentinean OP (orange pekoe) tea (black), Brazilian OP tea (black), Ceylan OP tea (black) and Darjeeling OP tea (green). The appearance of dry tea leaves were qualitatively characterized comparing with dry leaves standard. The attributes: colour, form, regularity of the leaves, fibre and stem cutting were evaluated The differences obtained were related to the differences produced by the effect of the fermentation process. Flavour and aroma descriptors of the tea liqueur were generated by a trained panel. Colour and astringency were evaluated in comparison with qualified standards using non structured linear scales. In order to relate the sensory analysis and the chemical composition for the different varieties of tea, following determinations were made: chemical moisture, dry material, aqueous extract, tannin and caffeine. Through multifactor regression analysis the equations in relation to the following chemical parameters were determined. Dry material, aqueous extract and tannins for colour and moisture, dry material and aqueous extract for astringency, respectively. Statistical analysis through ANOVA (3 variation sources: samples, judges and replications) showed for samples four significant different groups for astringency and three different groups for colour. No significant differences between judges or repetitions were found. By multifactor regression analysis of both, colour and astringency, on their dependence of chemist results were calculated in order to asses the corresponding equations.

A multi-factor designation method for mapping particulate-pollution control zones in China.

PubMed

Qin, Y; Xie, S D

2011-09-01

A multi-factor designation method for mapping particulate-pollution control zones was brought out through synthetically considering PM(10) pollution status, PM(10) anthropogenic emissions, fine particle pollution, long-range transport and economic situation. According to this method, China was divided into four different particulate-pollution control regions: PM Suspended Control Region, PM(10) Pollution Control Region, PM(2.5) Pollution Control Region and PM(10) and PM(2.5) Common Control Region, which accounted for 69.55%, 9.66%, 4.67% and 16.13% of China's territory, respectively. The PM(10) and PM(2.5) Common Control Region was mainly distributed in Bohai Region, Yangtze River Delta, Pearl River Delta, eastern of Sichuan province and Chongqing municipality, calling for immediate control of both PM(10) and PM(2.5). Cost-effective control effects can be achieved through concentrating efforts on PM(10) and PM(2.5) Common Control Region to address 60.32% of national PM(10) anthropogenic emissions. Air quality in districts belonging to PM(2.5) Pollution Control Region suggested that Chinese national ambient air quality standard for PM(10) was not strict enough. The result derived from application to China proved that this approach was feasible for mapping pollution control regions for a country with vast territory, complicated pollution characteristics and limited available monitoring data. Copyright © 2011 Elsevier B.V. All rights reserved.

An assessment of two-step linear regression and a multifactor probit analysis as alternatives to acute to chronic ratios in the estimation of chronic response from acute toxicity data to derive water quality guidelines.

PubMed

Slaughter, Andrew R; Palmer, Carolyn G; Muller, Wilhelmine J

2007-04-01

In aquatic ecotoxicology, acute to chronic ratios (ACRs) are often used to predict chronic responses from available acute data to derive water quality guidelines, despite many problems associated with this method. This paper explores the comparative protectiveness and accuracy of predicted guideline values derived from the ACR, linear regression analysis (LRA), and multifactor probit analysis (MPA) extrapolation methods applied to acute toxicity data for aquatic macroinvertebrates. Although the authors of the LRA and MPA methods advocate the use of extrapolated lethal effects in the 0.01% to 10% lethal concentration (LC0.01-LC10) range to predict safe chronic exposure levels to toxicants, the use of an extrapolated LC50 value divided by a safety factor of 5 was in addition explored here because of higher statistical confidence surrounding the LC50 value. The LRA LC50/5 method was found to compare most favorably with available experimental chronic toxicity data and was therefore most likely to be sufficiently protective, although further validation with the use of additional species is needed. Values derived by the ACR method were the least protective. It is suggested that there is an argument for the replacement of ACRs in developing water quality guidelines by the LRA LC50/5 method.

Ability of crassulacean acid metabolism plants to overcome interacting stresses in tropical environments.

PubMed

Lüttge, Ulrich

2010-01-01

Single stressors such as scarcity of water and extreme temperatures dominate the struggle for life in severely dry desert ecosystems or cold polar regions and at high elevations. In contrast, stress in the tropics typically arises from a dynamic network of interacting stressors, such as availability of water, CO(2), light and nutrients, temperature and salinity. This requires more plastic spatio-temporal responsiveness and versatility in the acquisition and defence of ecological niches. The mode of photosynthesis of crassulacean acid metabolism (CAM) is described and its flexible expression endows plants with powerful strategies for both acclimation and adaptation. Thus, CAM plants are able to inhabit many diverse habitats in the tropics and are not, as commonly thought, successful predominantly in dry, high-insolation habitats. Typical tropical CAM habitats or ecosystems include exposed lava fields, rock outcrops of inselbergs, salinas, savannas, restingas, high-altitude páramos, dry forests and moist forests. Morphotypical and physiotypical plasticity of CAM phenotypes allow a wide ecophysiological amplitude of niche occupation in the tropics. Physiological and biochemical plasticity appear more responsive by having more readily reversible variations in performance than do morphological adaptations. This makes CAM plants particularly fit for the multi-factor stressor networks of tropical forests. Thus, while the physiognomy of semi-deserts outside the tropics is often determined by tall succulent CAM plants, tropical forests house many more CAM plants in terms of quantity (biomass) and quality (species diversity).

Examination of Association to Autism of Common Genetic Variation in Genes Related to Dopamine

PubMed Central

Anderson, B.M.; Schnetz-Boutaud, N.; Bartlett, J.; Wright, H.H.; Abramson, R.K.; Cuccaro, M.L.; Gilbert, J.R.; Pericak-Vance, M.A.; Haines, J.L.

2010-01-01

Autism is a severe neurodevelopmental disorder characterized by a triad of complications. Autistic individuals display significant disturbances in language and reciprocal social interactions, combined with repetitive and stereotypic behaviors. Prevalence studies suggest that autism is more common than originally believed, with recent estimates citing a rate of one in 150. Although this genomic approach has yielded multiple suggestive regions, a specific risk locus has yet to be identified and widely confirmed. Because many etiologies have been suggested for this complex syndrome, we hypothesize that one of the difficulties in identifying autism genes is that multiple genetic variants may be required to significantly increase the risk of developing autism. Thus we took the alternative approach of examining 14 prominent dopamine pathway candidate genes for detailed study by genotyping 28 SNPs. Although we did observe a nominally significant association for rs2239535 (p=.008) on chromosome 20, single locus analysis did not reveal any results as significant after correction for multiple comparisons. No significant interaction was identified when Multifactor Dimensionality Reduction (MDR) was employed to test specifically for multilocus effects. Although genome-wide linkage scans in autism have provided support for linkage to various loci along the dopamine pathway, our study does not provide strong evidence of linkage or association to any specific gene or combination of genes within the pathway. These results demonstrate that common genetic variation within the tested genes located within this pathway at most play a minor to moderate role in overall autism pathogenesis. PMID:19360691

[Chronic fatigue syndrome in a cognitive perspective. A therapeutic model].

PubMed

d'Elia, Giacomo

2004-01-29

The cognitive approach to the treatment of chronic fatigue syndrome (CSF) is based on a multifactor etiological hypothesis, i.e. inaccurate beliefs and attitudes to the illness interact with pathophysiological processes, ineffective coping behaviours, negative states of mood, social problem, to perpetuate the illness. Patients suffering from CFS are supposed to be hypervigilant to somatic sensations and to interpret them as signs of impending physical catastrophe. The aim of the this paper is to describe the clinical implementation of principles of cognitive therapy in the treatment of CFS. Basic to the treatment approach is a collaborative, listening and empathic attitude, sensitive to the patient's personal beliefs and potential threats to self-esteem. The aim is to develop more useful, functional, formulations of the illness. The patient and the therapist work together to look at how the patient thinks about herself/himself and the illness, detect unhelpful attitudes, thoughts and mental images about the illness, and to make them accessible to Socratic reasoning. Graded behavioural interventions are planned in order to disconfirm unhelpful beliefs and reverse the spiral of tiredness, demoralization and reduced activity. The treatment is structured according to the general principles of cognitive therapy.

Novel Method of Production Decline Analysis

NASA Astrophysics Data System (ADS)

Xie, Shan; Lan, Yifei; He, Lei; Jiao, Yang; Wu, Yong

2018-02-01

ARPS decline curves is the most commonly used in oil and gas field due to its minimal data requirements and ease application. And prediction of production decline which is based on ARPS analysis rely on known decline type. However, when coefficient index are very approximate under different decline type, it is difficult to directly recognize decline trend of matched curves. Due to difficulties above, based on simulation results of multi-factor response experiments, a new dynamic decline prediction model is introduced with using multiple linear regression of influence factors. First of all, according to study of effect factors of production decline, interaction experimental schemes are designed. Based on simulated results, annual decline rate is predicted by decline model. Moreover, the new method is applied in A gas filed of Ordos Basin as example to illustrate reliability. The result commit that the new model can directly predict decline tendency without needing recognize decline style. From arithmetic aspect, it also take advantage of high veracity. Finally, the new method improves the evaluation method of gas well production decline in low permeability gas reservoir, which also provides technical support for further understanding of tight gas field development laws.

Prioritizing chronic obstructive pulmonary disease (COPD) candidate genes in COPD-related networks

PubMed Central

Zhang, Yihua; Li, Wan; Feng, Yuyan; Guo, Shanshan; Zhao, Xilei; Wang, Yahui; He, Yuehan; He, Weiming; Chen, Lina

2017-01-01

Chronic obstructive pulmonary disease (COPD) is a multi-factor disease, which could be caused by many factors, including disturbances of metabolism and protein-protein interactions (PPIs). In this paper, a weighted COPD-related metabolic network and a weighted COPD-related PPI network were constructed base on COPD disease genes and functional information. Candidate genes in these weighted COPD-related networks were prioritized by making use of a gene prioritization method, respectively. Literature review and functional enrichment analysis of the top 100 genes in these two networks suggested the correlation of COPD and these genes. The performance of our gene prioritization method was superior to that of ToppGene and ToppNet for genes from the COPD-related metabolic network or the COPD-related PPI network after assessing using leave-one-out cross-validation, literature validation and functional enrichment analysis. The top-ranked genes prioritized from COPD-related metabolic and PPI networks could promote the better understanding about the molecular mechanism of this disease from different perspectives. The top 100 genes in COPD-related metabolic network or COPD-related PPI network might be potential markers for the diagnosis and treatment of COPD. PMID:29262568

Prioritizing chronic obstructive pulmonary disease (COPD) candidate genes in COPD-related networks.

PubMed

Zhang, Yihua; Li, Wan; Feng, Yuyan; Guo, Shanshan; Zhao, Xilei; Wang, Yahui; He, Yuehan; He, Weiming; Chen, Lina

2017-11-28

Chronic obstructive pulmonary disease (COPD) is a multi-factor disease, which could be caused by many factors, including disturbances of metabolism and protein-protein interactions (PPIs). In this paper, a weighted COPD-related metabolic network and a weighted COPD-related PPI network were constructed base on COPD disease genes and functional information. Candidate genes in these weighted COPD-related networks were prioritized by making use of a gene prioritization method, respectively. Literature review and functional enrichment analysis of the top 100 genes in these two networks suggested the correlation of COPD and these genes. The performance of our gene prioritization method was superior to that of ToppGene and ToppNet for genes from the COPD-related metabolic network or the COPD-related PPI network after assessing using leave-one-out cross-validation, literature validation and functional enrichment analysis. The top-ranked genes prioritized from COPD-related metabolic and PPI networks could promote the better understanding about the molecular mechanism of this disease from different perspectives. The top 100 genes in COPD-related metabolic network or COPD-related PPI network might be potential markers for the diagnosis and treatment of COPD.

Transforming growth factor beta-3 and environmental factors and cleft lip with/without cleft palate.

PubMed

Guo, Zeqiang; Huang, Chengle; Ding, Kaihong; Lin, Jianyan; Gong, Binzhong

2010-07-01

To identify the interactions among two loci (C641A and G15572-) of transforming growth factor beta 3 (TGFbeta3), and exposures in pregnancy with cleft lip with/without cleft palate (CL/P), a hospital-based case-control study was conducted. Associations among offspring polymorphisms of TGFbeta3 C641A and G15572-, paternal smoking, paternal high-risk drinking, maternal passive smoking, and maternal multivitamin supplement with CL/P were analyzed by logistic regression analysis, and the results showed that maternal passive smoking exposures and maternal multivitamin use were associated with the risk of CL/P but offspring polymorphisms of TGFbeta3 C641A and G15572-, paternal smoking, and paternal high-risk drinking were not. Interactions among these variables were analyzed using the multifactor dimensionality reduction method, and the results showed that the two-factor model, including maternal passive smoking and TGFbeta3 C641A, among all models evaluated had the best ability to predict CL/P risk with a maximum cross-validation consistency (9/10) and a maximum average testing accuracy (0.5892; p = 0.0010). These findings suggested that maternal passive smoking exposure is a risk factor for CL/P, whereas maternal multivitamin supplement is a protective factor. The polymorphism of TGFbeta3 C641A participates in interaction effect for CL/P with environmental exposures, although the polymorphism was not associated with CL/P in single-locus analysis, and synergistic effect of TGFbeta3 C641A and maternal passive smoking could provide a new tool for identifying high-risk individuals of CL/P and also an additional evidence that CL/P is determined by both genetic and environmental factors.

A Fast Multiple-Kernel Method With Applications to Detect Gene-Environment Interaction.

PubMed

Marceau, Rachel; Lu, Wenbin; Holloway, Shannon; Sale, Michèle M; Worrall, Bradford B; Williams, Stephen R; Hsu, Fang-Chi; Tzeng, Jung-Ying

2015-09-01

Kernel machine (KM) models are a powerful tool for exploring associations between sets of genetic variants and complex traits. Although most KM methods use a single kernel function to assess the marginal effect of a variable set, KM analyses involving multiple kernels have become increasingly popular. Multikernel analysis allows researchers to study more complex problems, such as assessing gene-gene or gene-environment interactions, incorporating variance-component based methods for population substructure into rare-variant association testing, and assessing the conditional effects of a variable set adjusting for other variable sets. The KM framework is robust, powerful, and provides efficient dimension reduction for multifactor analyses, but requires the estimation of high dimensional nuisance parameters. Traditional estimation techniques, including regularization and the "expectation-maximization (EM)" algorithm, have a large computational cost and are not scalable to large sample sizes needed for rare variant analysis. Therefore, under the context of gene-environment interaction, we propose a computationally efficient and statistically rigorous "fastKM" algorithm for multikernel analysis that is based on a low-rank approximation to the nuisance effect kernel matrices. Our algorithm is applicable to various trait types (e.g., continuous, binary, and survival traits) and can be implemented using any existing single-kernel analysis software. Through extensive simulation studies, we show that our algorithm has similar performance to an EM-based KM approach for quantitative traits while running much faster. We also apply our method to the Vitamin Intervention for Stroke Prevention (VISP) clinical trial, examining gene-by-vitamin effects on recurrent stroke risk and gene-by-age effects on change in homocysteine level. © 2015 WILEY PERIODICALS, INC.

The association of 5-HTR2A-1438A/G, COMTVal158Met, MAOA-LPR, DATVNTR and 5-HTTVNTR gene polymorphisms and borderline personality disorder in female heroin-dependent Chinese subjects.

PubMed

Yang, Mei; Mamy, Jules; Wang, Qiang; Liao, Yan-Hui; Seewoobudul, Vasish; Xiao, Shui-Yuan; Hao, Wei

2014-04-03

To explore the association between the 5-HTR2A-1438A/G, COMTVal158Met, MAOA-LPR, DATVNTR and 5-HTTVNTR polymorphisms with co-morbid borderline personality disorder (BPD) in female heroin-dependent patients. In a case control study, we compared the polymorphic distributions of 5-HTR2A-1438A/G, COMTVal158Met, MAOA-LPR, DATVNTR and 5-HTTVNTR in 296 female heroin-dependent patients (including 61 patients with BPD and 235 without BPD) and 101 normal females by genotypes, alleles, and interaction between genes. Female heroin-dependent subjects with BPD have lower frequency of the high activity allele (L: 4 repeats (4R)) of MAOA-LPR than those female heroin-dependent subjects without BPD, and have higher 5-HTTVNTR 10R/10R genotype frequency than normal female controls, with adjusted P-value<0.05 (after adjusted for multiple testing by 1000-fold permutation tests) respectively. By MDR (Multifactor Dimensionality Reduction) analyses, the interactive effects between MAOA-LPR and 5-HTTVNTR, and among MAOA-LPR, 5-HTTVNTR and rs6311 were close to the significance level (P=0.05) in predicting the risk of co-morbidity of BPD and heroin dependence relative to normal female controls, with 1000-fold permutation testing P-value<0.06 however >0.05 respectively. 5-HTTVNTR and MAOA-LPR may have independent predictive effects on co-morbid BPD in female heroin-dependent patients; the gene-gene interactions between MAOA-LPR and 5-HTTVNTR, and among MAOA-LPR, 5-HTTVNTR and rs6311 might also be involved in the etiology of this co-morbidity. Copyright © 2013 Elsevier Inc. All rights reserved.

Multifactor Determinants of Visual Accommodation as a Critical Intervening Variable in the Perception of Size and Distance: Phase I Report

DTIC Science & Technology

1997-11-01

Expanded subset of the illustration to clarify the locus of the off-axis end point of retinal stimulation for correct accommodation. 55 Figure...12c. Expanded illustration to clarify the locus of the off -axis end point of retinal stimulation for myopic accommodation. 55 Figure 12d...Expanded illustration to clarify the locus of the off -axis end point of retinal stimulation for hyperopic accommodation. 56 Figure 13. Simplified

Multi-factor Effects on the Durability of Recycle Aggregate Concrete

NASA Astrophysics Data System (ADS)

Ma, Huan; Cui, Yu-Li; Zhu, Wen-Yu; Xie, Xian-Jie

2016-05-01

Recycled Aggregate Concrete (RAC) was prepared with different recycled aggregate replacement ratio, 0, 30%, 70% and 100% respectively. The performances of RAC were examined by the freeze-thaw cycle, carbonization and sulfate attack to assess the durability. Results show that test sequence has different effects on the durability of RAC; the durability is poorer when carbonation experiment was carried out firstly, and then other experiment was carried out again; the durability is better when recycled aggregate replacement ratio is 70%.

Multi-factor Analysis of Pre-control Fracture Simulations about Projectile Material

NASA Astrophysics Data System (ADS)

Wan, Ren-Yi; Zhou, Wei

2016-05-01

The study of projectile material pre-control fracture is helpful to improve the projectile metal effective fragmentation and the material utilization rate. Fragments muzzle velocity and lethality can be affected by the different explosive charge and the way of initiation. The finite element software can simulate the process of projectile explosive rupture which has a pre-groove in the projectile shell surface and analysis of typical node velocity change with time, to provides a reference for the design and optimization of precontrol frag.

PKPass

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

Adamson, Ryan M.

Password management solutions exist, but few are designed for enterprise systems administrators sharing oncall rotations. Due to the Multi-Factor Level of Assurance 4 effort, DOE is now distributing PIV cards with cryptographically signed certificate and private key pairs to administrators and other security-significant users. We utilize this public key infrastructure (PKI) to encrypt passwords for other recipients in a secure way. This is cross platform (works on OSX and Linux systems), and has already been adopted internally by the NCCS systems administration staff to replace their old password book system.

Comparative analysis of methods for detecting interacting loci

PubMed Central

2011-01-01

Background Interactions among genetic loci are believed to play an important role in disease risk. While many methods have been proposed for detecting such interactions, their relative performance remains largely unclear, mainly because different data sources, detection performance criteria, and experimental protocols were used in the papers introducing these methods and in subsequent studies. Moreover, there have been very few studies strictly focused on comparison of existing methods. Given the importance of detecting gene-gene and gene-environment interactions, a rigorous, comprehensive comparison of performance and limitations of available interaction detection methods is warranted. Results We report a comparison of eight representative methods, of which seven were specifically designed to detect interactions among single nucleotide polymorphisms (SNPs), with the last a popular main-effect testing method used as a baseline for performance evaluation. The selected methods, multifactor dimensionality reduction (MDR), full interaction model (FIM), information gain (IG), Bayesian epistasis association mapping (BEAM), SNP harvester (SH), maximum entropy conditional probability modeling (MECPM), logistic regression with an interaction term (LRIT), and logistic regression (LR) were compared on a large number of simulated data sets, each, consistent with complex disease models, embedding multiple sets of interacting SNPs, under different interaction models. The assessment criteria included several relevant detection power measures, family-wise type I error rate, and computational complexity. There are several important results from this study. First, while some SNPs in interactions with strong effects are successfully detected, most of the methods miss many interacting SNPs at an acceptable rate of false positives. In this study, the best-performing method was MECPM. Second, the statistical significance assessment criteria, used by some of the methods to control the type I error rate, are quite conservative, thereby limiting their power and making it difficult to fairly compare them. Third, as expected, power varies for different models and as a function of penetrance, minor allele frequency, linkage disequilibrium and marginal effects. Fourth, the analytical relationships between power and these factors are derived, aiding in the interpretation of the study results. Fifth, for these methods the magnitude of the main effect influences the power of the tests. Sixth, most methods can detect some ground-truth SNPs but have modest power to detect the whole set of interacting SNPs. Conclusion This comparison study provides new insights into the strengths and limitations of current methods for detecting interacting loci. This study, along with freely available simulation tools we provide, should help support development of improved methods. The simulation tools are available at: http://code.google.com/p/simulation-tool-bmc-ms9169818735220977/downloads/list. PMID:21729295

Comparative analysis of methods for detecting interacting loci.

PubMed

Chen, Li; Yu, Guoqiang; Langefeld, Carl D; Miller, David J; Guy, Richard T; Raghuram, Jayaram; Yuan, Xiguo; Herrington, David M; Wang, Yue

2011-07-05

Interactions among genetic loci are believed to play an important role in disease risk. While many methods have been proposed for detecting such interactions, their relative performance remains largely unclear, mainly because different data sources, detection performance criteria, and experimental protocols were used in the papers introducing these methods and in subsequent studies. Moreover, there have been very few studies strictly focused on comparison of existing methods. Given the importance of detecting gene-gene and gene-environment interactions, a rigorous, comprehensive comparison of performance and limitations of available interaction detection methods is warranted. We report a comparison of eight representative methods, of which seven were specifically designed to detect interactions among single nucleotide polymorphisms (SNPs), with the last a popular main-effect testing method used as a baseline for performance evaluation. The selected methods, multifactor dimensionality reduction (MDR), full interaction model (FIM), information gain (IG), Bayesian epistasis association mapping (BEAM), SNP harvester (SH), maximum entropy conditional probability modeling (MECPM), logistic regression with an interaction term (LRIT), and logistic regression (LR) were compared on a large number of simulated data sets, each, consistent with complex disease models, embedding multiple sets of interacting SNPs, under different interaction models. The assessment criteria included several relevant detection power measures, family-wise type I error rate, and computational complexity. There are several important results from this study. First, while some SNPs in interactions with strong effects are successfully detected, most of the methods miss many interacting SNPs at an acceptable rate of false positives. In this study, the best-performing method was MECPM. Second, the statistical significance assessment criteria, used by some of the methods to control the type I error rate, are quite conservative, thereby limiting their power and making it difficult to fairly compare them. Third, as expected, power varies for different models and as a function of penetrance, minor allele frequency, linkage disequilibrium and marginal effects. Fourth, the analytical relationships between power and these factors are derived, aiding in the interpretation of the study results. Fifth, for these methods the magnitude of the main effect influences the power of the tests. Sixth, most methods can detect some ground-truth SNPs but have modest power to detect the whole set of interacting SNPs. This comparison study provides new insights into the strengths and limitations of current methods for detecting interacting loci. This study, along with freely available simulation tools we provide, should help support development of improved methods. The simulation tools are available at: http://code.google.com/p/simulation-tool-bmc-ms9169818735220977/downloads/list.

Evidence for epistasis between SLC6A4 and ITGB3 in autism etiology and in the determination of platelet serotonin levels.

PubMed

Coutinho, Ana M; Sousa, Inês; Martins, Madalena; Correia, Catarina; Morgadinho, Teresa; Bento, Celeste; Marques, Carla; Ataíde, Assunção; Miguel, Teresa S; Moore, Jason H; Oliveira, Guiomar; Vicente, Astrid M

2007-04-01

Autism is a neurodevelopmental disorder of unclear etiology. The consistent finding of platelet hyperserotonemia in a proportion of patients and its heritability within affected families suggest that genes involved in the serotonin system play a role in this disorder. The role in autism etiology of seven candidate genes in the serotonin metabolic and neurotransmission pathways and mapping to autism linkage regions (SLC6A4, HTR1A, HTR1D, HTR2A, HTR5A, TPH1 and ITGB3) was analyzed in a sample of 186 nuclear families. The impact of interactions among these genes in autism was assessed using the multifactor-dimensionality reduction (MDR) method in 186 patients and 181 controls. We further evaluated whether the effect of specific gene variants or gene interactions associated with autism etiology might be mediated by their influence on serotonin levels, using the quantitative transmission disequilibrium test (QTDT) and the restricted partition method (RPM), in a sample of 109 autistic children. We report a significant main effect of the HTR5A gene in autism (P = 0.0088), and a significant three-locus model comprising a synergistic interaction between the ITGB3 and SLC6A4 genes with an additive effect of HTR5A (P < 0.0010). In addition to the previously reported contribution of SLC6A4, we found significant associations of ITGB3 haplotypes with serotonin level distribution (P = 0.0163). The most significant models contributing to serotonin distribution were found for interactions between TPH1 rs4537731 and SLC6A4 haplotypes (P = 0.002) and between HTR1D rs6300 and SLC6A4 haplotypes (P = 0.013). In addition to the significant independent effects, evidence for interaction between SLC6A4 and ITGB3 markers was also found. The overall results implicate SLC6A4 and ITGB3 gene interactions in autism etiology and in serotonin level determination, providing evidence for a common underlying genetic mechanism and a molecular explanation for the association of platelet hyperserotonemia with autism.

The FOXO1 Gene-Obesity Interaction Increases the Risk of Type 2 Diabetes Mellitus in a Chinese Han Population.

PubMed

Gong, Lilin; Li, Rong; Ren, Wei; Wang, Zengchan; Wang, Zhihong; Yang, Maosheng; Zhang, Suhua

2017-02-01

Here, we aimed to study the effect of the forkhead box O1-insulin receptor substrate 2 (FOXO1-IRS2) gene interaction and the FOXO1 and IRS2 genes-environment interaction for the risk of type 2 diabetes mellitus (T2DM) in a Chinese Han population. We genotyped 7 polymorphism sites of FOXO1 gene and IRS2 gene in 780 unrelated Chinese Han people (474 cases of T2DM, 306 cases of healthy control). The risk of T2DM in individuals with AA genotype for rs7986407 and CC genotype for rs4581585 in FOXO1 gene was 2.092 and 2.57 times higher than that with GG genotype (odds ratio [OR] = 2.092; 95% confidence interval [CI] = 1.178-3.731; P = 0.011) and TT genotype (OR = 2.571; 95% CI = 1.404-4.695; P = 0.002), respectively. The risk of T2DM in individuals with GG genotype for Gly1057Asp in IRS2 gene was 1.42 times higher than that with AA genotype (OR = 1.422; 95% CI = 1.037-1.949; P = 0.029). The other 4 single nucleotide polymorphisms (SNPs) had no significant association with T2DM (P > 0.05). Multifactor dimensionality reduction (MDR) analysis showed that the interaction between SNPs rs7986407 and rs4325426 in FOXO1 gene and waist was the best model confirmed by interaction analysis, closely associating with T2DM. There was an increased risk for T2DM in the case of non-obesity with genotype combined AA/CC, AA/AC or AG/AA for rs7986407 and rs4325426, and obesity with genotype AA for rs7986407 or AA for rs4325426 (OR = 3.976; 95% CI = 1.156-13.675; P value from sign test [P(sign)] = 0.025; P value from permutation test [P(perm)] = 0.000-0.001). Together, this study indicates an association of FOXO1 and IRS2 gene polymorphisms with T2DM in Chinese Han population, supporting FOXO1-obesity interaction as a key factor for the risk of T2DM.

The combined effects of the 5-HTTLPR and 5-HTR1A genes modulates the relationship between negative life events and major depressive disorder in a Chinese population.

PubMed

Zhang, Kerang; Xu, Qi; Xu, Yong; Yang, Hong; Luo, Jinxiu; Sun, Yan; Sun, Ning; Wang, Shan; Shen, Yan

2009-04-01

Serotonin transporter (5-HTT) and 5-HT receptor (5-HTR) involved in the neurotransmission of 5-HT may play an important role in the development of major depression disorder (MDD). Several lines of evidence suggested that the gene-environment interaction may confer susceptibility to depression. The aim of this study is to analyze the combined effect of four serotonin-related genes and two environmental factors on MDD in a Chinese population. This study recruited a total of 401 patients with MDD and 391 age- and gender-matched control subjects. They were all Chinese Han origin. Negative life events and objective social supports were assessed using standard rating scales. Six polymorphisms in the four serotonin-related genes (5-HTT, 5-HTR1A, 5-HTR1B and 5-HTR2A) were selected to detect. The analyses of the gene-environment interactions were performed by the Multifactor Dimensionality Reduction (MDR). Allelic associations between patients with MDD and controls were observed for the polymorphism of 5-HTTLPR and for rs6295 at the 5-HTR1A locus. The 5-HTTLPR polymorphism was associated with negative life events on MDD. A three-way interaction between the 5-HTTLPR polymorphism, rs6295 and negative life events on MDD was found in the individuals aged from 20 years to 29 years. In addition, the individuals carrying the L/L genotype of 5-HTTLPR could be susceptible to MDD when exposed to negative life events. The 5-HTTLPR polymorphism may modify the interaction between negative life events and MDD in the Chinese population. To our knowledge, this is the first report on the combined effect for the 5-HTTLPR polymorphism and 5-HTR1A genes on modifying the response to negative life events conferring susceptibility to MDD in the 20-29 year group.

Relationship of polymorphisms and haplotype in interleukin-16 and adiponectin gene with late-onset Alzheimer’s disease risk

PubMed Central

Yin, Honglei; Zhang, Yuzhen; Hua, Linlin; Li, Jinfeng; Zeng, Zhilei; Yang, Xiaopeng; Gong, Bin; Geng, Shuang; Liu, Yajun; Zhang, Hui; Liu, Yanqiu; Zhao, Jing; Wang, Yunliang

2017-01-01

Aims To investigate the impact of Interleukin-16 (IL- 16) and Adiponectin (ANP) gene single nucleotide polymorphisms (SNPs), gene- gene interactions and haplotype on late-onset Alzheimer’s disease (LOAD) risk. Methods Hardy-Weinberg equilibrium (HWE), haplotype and pairwise linkage disequilibrium (LD) analysis were investigated by using SNPstats (available online at http://bioinfo.iconcologia.net/SNPstats). Generalized multifactor dimensionality reduction (GMDR) was used to examine interaction among 4 SNPs, odds ratio (OR) and 95% confident interval (95%CI) were calculated by logistic regression model. Results LOAD risk was significantly higher in carriers of rs266729- G allele than those with CC genotype (CG+ GG versus CC), OR (95%CI) =1.61 (1.26-1.96), and higher in carriers of rs1501299- T allele, OR (95%CI) = 1.62 (1.32-2.12), lower in carriers of rs4072111- T allele, adjusted OR (95%CI) =0.65 (0.44-0.93). We also found a significant gene- gene interaction between rs266729 and rs4072111. Participants with CG or GG of rs266729 and CC of rs4072111 genotype have the highest LOAD risk, OR (95%CI) = 2.62 (1.64 -3.58). Haplotype containing the rs266729- G and rs1501299- T alleles were associated with increased LOAD risk, OR (95%CI)= 1.83 (1.32- 2.43), and haplotype containing the rs1131445- C and rs4072111- T alleles were associated with decreased LOAD risk, OR (95%CI)= 0.53 (0.18- 0.95). Conclusions We concluded that rs266729 and rs1501299 minor alleles were associated with increased LOAD risk, but rs4072111 minor allele was associated with decreased LOAD risk. We also found that interaction involving rs266729 and rs4072111, and haplotype combinations were associated with LOAD risk. PMID:29108295

Random matrix ensembles for many-body quantum systems

NASA Astrophysics Data System (ADS)

Vyas, Manan; Seligman, Thomas H.

2018-04-01

Classical random matrix ensembles were originally introduced in physics to approximate quantum many-particle nuclear interactions. However, there exists a plethora of quantum systems whose dynamics is explained in terms of few-particle (predom-inantly two-particle) interactions. The random matrix models incorporating the few-particle nature of interactions are known as embedded random matrix ensembles. In the present paper, we provide a brief overview of these two ensembles and illustrate how the embedded ensembles can be successfully used to study decoherence of a qubit interacting with an environment, both for fermionic and bosonic embedded ensembles. Numerical calculations show the dependence of decoherence on the nature of the environment.

Multifactor valuation models of energy futures and options on futures

NASA Astrophysics Data System (ADS)

Bertus, Mark J.

The intent of this dissertation is to investigate continuous time pricing models for commodity derivative contracts that consider mean reversion. The motivation for pricing commodity futures and option on futures contracts leads to improved practical risk management techniques in markets where uncertainty is increasing. In the dissertation closed-form solutions to mean reverting one-factor, two-factor, three-factor Brownian motions are developed for futures contracts. These solutions are obtained through risk neutral pricing methods that yield tractable expressions for futures prices, which are linear in the state variables, hence making them attractive for estimation. These functions, however, are expressed in terms of latent variables (i.e. spot prices, convenience yield) which complicate the estimation of the futures pricing equation. To address this complication a discussion on Dynamic factor analysis is given. This procedure documents latent variables using a Kalman filter and illustrations show how this technique may be used for the analysis. In addition, to the futures contracts closed form solutions for two option models are obtained. Solutions to the one- and two-factor models are tailored solutions of the Black-Scholes pricing model. Furthermore, since these contracts are written on the futures contracts, they too are influenced by the same underlying parameters of the state variables used to price the futures contracts. To conclude, the analysis finishes with an investigation of commodity futures options that incorporate random discrete jumps.

Screening large-scale association study data: exploiting interactions using random forests.

PubMed

Lunetta, Kathryn L; Hayward, L Brooke; Segal, Jonathan; Van Eerdewegh, Paul

2004-12-10

Genome-wide association studies for complex diseases will produce genotypes on hundreds of thousands of single nucleotide polymorphisms (SNPs). A logical first approach to dealing with massive numbers of SNPs is to use some test to screen the SNPs, retaining only those that meet some criterion for further study. For example, SNPs can be ranked by p-value, and those with the lowest p-values retained. When SNPs have large interaction effects but small marginal effects in a population, they are unlikely to be retained when univariate tests are used for screening. However, model-based screens that pre-specify interactions are impractical for data sets with thousands of SNPs. Random forest analysis is an alternative method that produces a single measure of importance for each predictor variable that takes into account interactions among variables without requiring model specification. Interactions increase the importance for the individual interacting variables, making them more likely to be given high importance relative to other variables. We test the performance of random forests as a screening procedure to identify small numbers of risk-associated SNPs from among large numbers of unassociated SNPs using complex disease models with up to 32 loci, incorporating both genetic heterogeneity and multi-locus interaction. Keeping other factors constant, if risk SNPs interact, the random forest importance measure significantly outperforms the Fisher Exact test as a screening tool. As the number of interacting SNPs increases, the improvement in performance of random forest analysis relative to Fisher Exact test for screening also increases. Random forests perform similarly to the univariate Fisher Exact test as a screening tool when SNPs in the analysis do not interact. In the context of large-scale genetic association studies where unknown interactions exist among true risk-associated SNPs or SNPs and environmental covariates, screening SNPs using random forest analyses can significantly reduce the number of SNPs that need to be retained for further study compared to standard univariate screening methods.

How multiple factors control evapotranspiration in North America evergreen needleleaf forests.

PubMed

Chen, Yueming; Xue, Yueju; Hu, Yueming

2018-05-01

Identifying the factors dominating ecosystem water flux is a critical step for predicting evapotranspiration (ET). Here, the fuzzy rough set with binary shuffled frog leaping (BSFL-FRSA) was used to identify both individual factors and multi-factor combinations that dominate the half-hourly ET variation at evergreen needleleaf forests (ENFs) sites across three different climatic zones in the North America. Among 21factors, air temperature (TA), atmospheric CO 2 concentration (CCO 2 ), soil temperature (TS), soil water content (SWC) and net radiation (NETRAD) were evaluated as dominant single factors, contributed to the ET variation averaged for all ENF sites by 48%, 36%, 32%, 18% and 13%, respectively. While the importance order would vary with climatic zones, and TA was assessed as the most influential factor at a single climatic zone level, counting a contribution rate of 54.7%, 49.9%, and 38.6% in the subarctic, warm summer continental, and Mediterranean climatic zones, respectively. In view of impacts of each multi-factors combination on ET, both TA and CCO 2 made a contribution of 71% across three climate zones; the combination of TA, CCO 2 and NETRAD was evaluated the most dominant at Mediterranean and subarctic ENF sites, and the combination of TA, CCO 2 and TS at warm summer continental sites. Our results suggest that temperature was most critical for ET variation at the warm summer continental ENF. Copyright © 2017 Elsevier B.V. All rights reserved.

Gene Polymorphism Association with Type 2 Diabetes and Related Gene-Gene and Gene-Environment Interactions in a Uyghur Population

PubMed Central

Xiao, Shan; Zeng, Xiaoyun; Fan, Yong; Su, Yinxia; Ma, Qi; Zhu, Jun; Yao, Hua

2016-01-01

Background We investigated the association between 8 single-nucleotide polymorphisms (SNPs) at 3 genetic loci (CDKAL1, CDKN2A/2B and FTO) with type 2 diabetes (T2D) in a Uyghur population. Material/Methods A case-control study of 879 Uyghur patients with T2D and 895 non-diabetic Uyghur controls was conducted at the Hospital of Xinjiang Medical University between 2010 and 2013. Eight SNPs in CDKAL1, CDKN2A/2B and FTO were analyzed using Sequenom MassARRAY®SNP genotyping. Factors associated with T2D were assessed by logistic regression analyses. Gene-gene and gene-environment interactions were analyzed by generalized multifactor dimensionality reduction. Results Genotype distributions of rs10811661 (CDKN2A/2B), rs7195539, rs8050136, and rs9939609 (FTO) and allele frequencies of rs8050136 and rs9939609 differed significantly between diabetes and control groups (all P<0.05). While rs10811661, rs8050136, and rs9939609 were eliminated after adjusting for covariates (P>0.05), rs7195539 distribution differed significantly in co-dominant and dominant models (P<0.05). In gene-gene interaction analysis, after adjusting for covariates the two-locus rs10811661-rs7195539 interaction model had a cross-validation consistency of 10/10 and the highest balanced accuracy of 0.5483 (P=0.014). In gene-environment interaction analysis, the 3-locus interaction model TG-HDL-family history of diabetes had a cross-validation consistency of 10/10 and the highest balanced accuracy of 0.7072 (P<0.001). The 4-locus interaction model, rs7195539-TG-HDL-family history of diabetes had a cross-validation consistency of 8/10 (P<0.001). Conclusions Polymorphisms in CDKN2A/2B and FTO, but not CDKAL1, may be associated with T2D, and alleles rs8050136 and rs9939609 are likely risk alleles for T2D in this population. There were potential interactions among CDKN2A/2B (rs10811661) – FTO (rs7195539) or FTO (rs7195539)-TG-HDL-family history of diabetes in the pathogenesis of T2D in a Uyghur population. PMID:26873362

The interaction of reward genes with environmental factors in contribution to alcoholism in mexican americans.

PubMed

Du, Yanlei; Wan, Yu-Jui Yvonne

2009-12-01

Alcoholism is a polygenic disorder resulting from reward deficiency; polymorphisms in reward genes including serotonin transporter (5-HTT)-linked polymorphic region (5-HTTLPR), A118G in opioid receptor mu1 (OPRM1), and -141C Insertion/Deletion (Ins/Del) in dopamine receptor D2 (DRD2) as well as environmental factors (education and marital status) might affect the risk of alcoholism. Objective of the current study was to examine the main and interacting effect of these 3 polymorphisms and 2 environmental factors in contribution to alcoholism in Mexican Americans. Genotyping of 5-HTTLPR, OPRM1 A118G, and DRD2-141C Ins/Del was performed in 365 alcoholics and 338 nonalcoholic controls of Mexican Americans who were gender- and age-matched. Alcoholics were stratified according to tertiles of MAXDRINKS, which denotes the largest number of drinks consumed in one 24-hour period. Data analysis was done in the entire data set and in each alcoholic stratum. Multinomial logistic regression was conducted to explore the main effect of 3 polymorphisms and 2 environmental factors (education and marital status); classification tree, generalized multifactor dimensionality reduction (GMDR) analysis, and polymorphism interaction analysis version 2.0 (PIA 2) program were used to study factor interaction. Main effect of education, OPRM1, and DRD2 was detected in alcoholic stratum of moderate and/or largest MAXDRINKS with education < or =12 years, OPRM1 118 A/A, and DRD2 -141C Ins/Ins being risk factors. Classification tree analysis, GMDR analysis, and PIA 2 program all supported education*OPRM1 interaction in alcoholics of largest MAXDRINKS with education < or =12 years coupled with OPRM1 A/A being a high risk factor; dendrogram showed synergistic interaction between these 2 factors; dosage-effect response was also observed for education*OPRM1 interaction. No definite effect of marital status and 5-HTTLPR in pathogenesis of alcoholism was observed. Our results suggest main effect of education background, OPRM1 A118G, and DRD2 -141C Ins/Del as well as education*OPRM1 interaction in contribution to moderate and/or severe alcoholism in Mexican Americans. Functional relevance of these findings still needs to be explored.

Membrane fouling in a submerged membrane bioreactor: An unified approach to construct topography and to evaluate interaction energy between two randomly rough surfaces.

PubMed

Cai, Xiang; Shen, Liguo; Zhang, Meijia; Chen, Jianrong; Hong, Huachang; Lin, Hongjun

2017-11-01

Quantitatively evaluating interaction energy between two randomly rough surfaces is the prerequisite to quantitatively understand and control membrane fouling in membrane bioreactors (MBRs). In this study, a new unified approach to construct rough topographies and to quantify interaction energy between a randomly rough particle and a randomly rough membrane was proposed. It was found that, natural rough topographies of both foulants and membrane could be well constructed by a modified two-variable Weierstrass-Mandelbrot (WM) function included in fractal theory. Spatial differential relationships between two constructed surfaces were accordingly established. Thereafter, a new approach combining these relationships, surface element integration (SEI) approach and composite Simpson's rule was deduced to calculate the interaction energy between two randomly rough surfaces in a submerged MBR. The obtained results indicate the profound effects of surface morphology on interaction energy and membrane fouling. This study provided a basic approach to investigate membrane fouling and interface behaviors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Random-field-induced disordering mechanism in a disordered ferromagnet: Between the Imry-Ma and the standard disordering mechanism

NASA Astrophysics Data System (ADS)

Andresen, Juan Carlos; Katzgraber, Helmut G.; Schechter, Moshe

2017-12-01

Random fields disorder Ising ferromagnets by aligning single spins in the direction of the random field in three space dimensions, or by flipping large ferromagnetic domains at dimensions two and below. While the former requires random fields of typical magnitude similar to the interaction strength, the latter Imry-Ma mechanism only requires infinitesimal random fields. Recently, it has been shown that for dilute anisotropic dipolar systems a third mechanism exists, where the ferromagnetic phase is disordered by finite-size glassy domains at a random field of finite magnitude that is considerably smaller than the typical interaction strength. Using large-scale Monte Carlo simulations and zero-temperature numerical approaches, we show that this mechanism applies to disordered ferromagnets with competing short-range ferromagnetic and antiferromagnetic interactions, suggesting its generality in ferromagnetic systems with competing interactions and an underlying spin-glass phase. A finite-size-scaling analysis of the magnetization distribution suggests that the transition might be first order.

Early neurological and cognitive impairments in subclinical cerebrovascular disease.

PubMed

Atanassova, Penka A; Massaldjieva, Radka I; Dimitrov, Borislav D; Aleksandrov, Aleksandar S; Semerdjieva, Maria A; Tsvetkova, Silvia B; Chalakova, Nedka T; Chompalov, Kostadin A

2016-01-01

The subclinical cerebrovascular disease (SCVD) is an important public health problem with demonstrated prognostic significance for stroke, future cognitive decline, and progression to dementia. The earliest possible detection of the silent presence of SCVD in adults at age at risk with normal functioning is very important for both clinical doctors and scientists. Seventy-seven adult volunteers, recruited during the years 2005-2007, with mean age 58.7 (standard deviation 5.9) years, were assessed by four subtests from the Cambridge Neuropsychological Test Automated Battery (CANTAB)-Eclipse cognitive assessment system. We used a questionnaire survey for the presence of cerebrovascular risk factors (CVRFs) such as arterial hypertension, smoking and dyslipidemia, among others, as well as instrumental (Doppler examination) and neurological magnetic resonance imaging (MRI) procedures. Descriptive statistics, comparison (t-test, Chi-square) and univariate methods were used as followed by multifactor logistic regression and receiver operating characteristics analyses. The risk factor questionnaire revealed nonspecific symptoms in 44 (67.7%) of the subjects. In 42 (64.6%) of all 65 subjects, we found at least one of the conventional CVRFs. Abnormal findings from the extra- and trans-cranial Doppler examination were established in 38 (58.5%) of all studied volunteers. Thirty-four subjects had brain MRI (52.3%), and abnormal findings were found in 12 (35.3%) of them. Two of the four subtests of CANTAB tool appeared to be potentially promising predictors of the outcome, as found at the univariate analysis (spatial working memory 1 [SWM1] total errors; intra-extra dimensional set 1 [IED1] total errors [adjusted]; IED2 total trials [adjusted]). We established that the best accuracy of 82.5% was achieved by a multifactor interaction logistic regression model, with the role CVRF and combined CANTAB predictor "IED total ratio (errors/trials) × SWM1 total errors" (P = 0.006). Our results have contributed to the hypothesis that it is possible to identify, by noninvasive methods, subjects at age at risk who have mild degree of cognitive impairment and to establish the significant relationship of this impairment with existing CVRFs, nonspecific symptoms and subclinical abnormal brain Doppler/MRI findings. We created a combined neuropsychological predictor that was able to clearly distinguish between the presence and absence of abnormal Doppler/MRI findings. This pilot prognostic model showed a relatively high accuracy of >80%; therefore, the predictors may serve as biomarkers for SCVD in subjects at age at risk (51-65 years).

Ability of crassulacean acid metabolism plants to overcome interacting stresses in tropical environments

PubMed Central

Lüttge, Ulrich

2010-01-01

Background and aims Single stressors such as scarcity of water and extreme temperatures dominate the struggle for life in severely dry desert ecosystems or cold polar regions and at high elevations. In contrast, stress in the tropics typically arises from a dynamic network of interacting stressors, such as availability of water, CO2, light and nutrients, temperature and salinity. This requires more plastic spatio-temporal responsiveness and versatility in the acquisition and defence of ecological niches. Crassulacean acid metabolism The mode of photosynthesis of crassulacean acid metabolism (CAM) is described and its flexible expression endows plants with powerful strategies for both acclimation and adaptation. Thus, CAM plants are able to inhabit many diverse habitats in the tropics and are not, as commonly thought, successful predominantly in dry, high-insolation habitats. Tropical CAM habitats Typical tropical CAM habitats or ecosystems include exposed lava fields, rock outcrops of inselbergs, salinas, savannas, restingas, high-altitude páramos, dry forests and moist forests. Morphotypical and physiotypical plasticity of CAM Morphotypical and physiotypical plasticity of CAM phenotypes allow a wide ecophysiological amplitude of niche occupation in the tropics. Physiological and biochemical plasticity appear more responsive by having more readily reversible variations in performance than do morphological adaptations. This makes CAM plants particularly fit for the multi-factor stressor networks of tropical forests. Thus, while the physiognomy of semi-deserts outside the tropics is often determined by tall succulent CAM plants, tropical forests house many more CAM plants in terms of quantity (biomass) and quality (species diversity). PMID:22476063

Examination of association to autism of common genetic variationin genes related to dopamine.

PubMed

Anderson, B M; Schnetz-Boutaud, N; Bartlett, J; Wright, H H; Abramson, R K; Cuccaro, M L; Gilbert, J R; Pericak-Vance, M A; Haines, J L

2008-12-01

Autism is a severe neurodevelopmental disorder characterized by a triad of complications. Autistic individuals display significant disturbances in language and reciprocal social interactions, combined with repetitive and stereotypic behaviors. Prevalence studies suggest that autism is more common than originally believed, with recent estimates citing a rate of one in 150. Although multiple genetic linkage and association studies have yielded multiple suggestive genes or chromosomal regions, a specific risk locus has yet to be identified and widely confirmed. Because many etiologies have been suggested for this complex syndrome, we hypothesize that one of the difficulties in identifying autism genes is that multiple genetic variants may be required to significantly increase the risk of developing autism. Thus, we took the alternative approach of examining 14 prominent dopamine pathway candidate genes for detailed study by genotyping 28 single nucleotide polymorphisms. Although we did observe a nominally significant association for rs2239535 (P=0.008) on chromosome 20, single-locus analysis did not reveal any results as significant after correction for multiple comparisons. No significant interaction was identified when Multifactor Dimensionality Reduction was employed to test specifically for multilocus effects. Although genome-wide linkage scans in autism have provided support for linkage to various loci along the dopamine pathway, our study does not provide strong evidence of linkage or association to any specific gene or combination of genes within the pathway. These results demonstrate that common genetic variation within the tested genes located within this pathway at most play a minor to moderate role in overall autism pathogenesis.

Artificial neural network model for predicting the bioavailability of tacrolimus in patients with renal transplantation

PubMed Central

Thishya, Kalluri; Vattam, Kiran Kumar; Naushad, Shaik Mohammad; Raju, Shree Bhushan

2018-01-01

The objective of the current study was to explore the role of ABCB1 and CYP3A5 genetic polymorphisms in predicting the bioavailability of tacrolimus and the risk for post-transplant diabetes. Artificial neural network (ANN) and logistic regression (LR) models were used to predict the bioavailability of tacrolimus and risk for post-transplant diabetes, respectively. The five-fold cross-validation of ANN model showed good correlation with the experimental data of bioavailability (r2 = 0.93–0.96). Younger age, male gender, optimal body mass index were shown to exhibit lower bioavailability of tacrolimus. ABCB1 1236 C>T and 2677G>T/A showed inverse association while CYP3A5*3 showed a positive association with the bioavailability of tacrolimus. Gender bias was observed in the association with ABCB1 3435 C>T polymorphism. CYP3A5*3 was shown to interact synergistically in increasing the bioavailability in combination with ABCB1 1236 TT or 2677GG genotypes. LR model showed an independent association of ABCB1 2677 G>T/A with post transplant diabetes (OR: 4.83, 95% CI: 1.22–19.03). Multifactor dimensionality reduction analysis (MDR) revealed that synergistic interactions between CYP3A5*3 and ABCB1 2677 G>T/A as the determinants of risk for post-transplant diabetes. To conclude, the ANN and MDR models explore both individual and synergistic effects of variables in modulating the bioavailability of tacrolimus and risk for post-transplant diabetes. PMID:29621269

[Clinical genealogy and genetic-mathematical study of families of probands with uterine cancer in the Chernovitsy Region].

PubMed

Galina, K P; Peresun'ko, A P; Glushchenko, N N

2001-01-01

Complex clinic-genealogical and genetic-mathematical investigation of 482 patients with uterus cancer from Chernovtsy region was carried out. It was proved that primary in the population is multifactoral origin of uterus cancer. Percentage of genetic component in general susceptibility to disease was 11.40 9.40. Recurrent risk of the malignant tumor in progeny has been estimated. Results of the investigation are the base for development and execution of uterus cancer precaution and segregated with it oncopathology in proband relatives.

Continuous Cultivation for Apparent Optimization of Defined Media for Cellulomonas sp. and Bacillus cereus

PubMed Central

Summers, R. J.; Boudreaux, D. P.; Srinivasan, V. R.

1979-01-01

Steady-state continuous culture was used to optimize lean chemically defined media for a Cellulomonas sp. and Bacillus cereus strain T. Both organisms were extremely sensitive to variations in trace-metal concentrations. However, medium optimization by this technique proved rapid, and multifactor screening was easily conducted by using a minimum of instrumentation. The optimized media supported critical dilution rates of 0.571 and 0.467 h−1 for Cellulomonas and Bacillus, respectively. These values approximated maximum growth rate values observed in batch culture. PMID:16345417

Assessment Methods of Groundwater Overdraft Area and Its Application

NASA Astrophysics Data System (ADS)

Dong, Yanan; Xing, Liting; Zhang, Xinhui; Cao, Qianqian; Lan, Xiaoxun

2018-05-01

Groundwater is an important source of water, and long-term large demand make groundwater over-exploited. Over-exploitation cause a lot of environmental and geological problems. This paper explores the concept of over-exploitation area, summarizes the natural and social attributes of over-exploitation area, as well as expounds its evaluation methods, including single factor evaluation, multi-factor system analysis and numerical method. At the same time, the different methods are compared and analyzed. And then taking Northern Weifang as an example, this paper introduces the practicality of appraisal method.

Robust and Comprehensive Analysis of 20 Osteoporosis Candidate Genes by Very High-Density Single-Nucleotide Polymorphism Screen Among 405 White Nuclear Families Identified Significant Association and Gene–Gene Interaction

PubMed Central

Xiong, Dong-Hai; Shen, Hui; Zhao, Lan-Juan; Xiao, Peng; Yang, Tie-Lin; Guo, Yan; Wang, Wei; Guo, Yan-Fang; Liu, Yong-Jun; Recker, Robert R; Deng, Hong-Wen

2007-01-01

Many “novel” osteoporosis candidate genes have been proposed in recent years. To advance our knowledge of their roles in osteoporosis, we screened 20 such genes using a set of high-density SNPs in a large family-based study. Our efforts led to the prioritization of those osteoporosis genes and the detection of gene–gene interactions. Introduction We performed large-scale family-based association analyses of 20 novel osteoporosis candidate genes using 277 single nucleotide polymorphisms (SNPs) for the quantitative trait BMD variation and the qualitative trait osteoporosis (OP) at three clinically important skeletal sites: spine, hip, and ultradistal radius (UD). Materials and Methods One thousand eight hundred seventy-three subjects from 405 white nuclear families were genotyped and analyzed with an average density of one SNP per 4 kb across the 20 genes. We conducted association analyses by SNP- and haplotype-based family-based association test (FBAT) and performed gene–gene interaction analyses using multianalytic approaches such as multifactor-dimensionality reduction (MDR) and conditional logistic regression. Results and Conclusions We detected four genes (DBP, LRP5, CYP17, and RANK) that showed highly suggestive associations (10,000-permutation derived empirical global p ≤ 0.01) with spine BMD/OP; four genes (CYP19, RANK, RANKL, and CYP17) highly suggestive for hip BMD/OP; and four genes (CYP19, BMP2, RANK, and TNFR2) highly suggestive for UD BMD/OP. The associations between BMP2 with UD BMD and those between RANK with OP at the spine, hip, and UD also met the experiment-wide stringent criterion (empirical global p ≤ 0.0007). Sex-stratified analyses further showed that some of the significant associations in the total sample were driven by either male or female subjects. In addition, we identified and validated a two-locus gene–gene interaction model involving GCR and ESR2, for which prior biological evidence exists. Our results suggested the prioritization of osteoporosis candidate genes from among the many proposed in recent years and revealed the significant gene–gene interaction effects influencing osteoporosis risk. PMID:17002564

Contribution of genome-environment interaction to pre-eclampsia in a Havana Maternity Hospital.

PubMed

Lardoeyt, Roberto; Vargas, Gerardo; Lumpuy, Jairo; García, Ramón; Torres, Yuselis

2013-07-01

Pre-eclampsia is a major cause of morbidity and mortality during pregnancy worldwide and is among the leading causes of maternal mortality in Cuba. It is a complex, multifactoral disease, in which interaction of genetic and environmental factors should not be overlooked if the goal is proper risk assessment to support personalized preventive genetic counseling and more effective prenatal care to prevent pregnancy complications. Determine the contribution to pre-eclampsia of interaction between a predisposing genome and adverse environmental factors in pregnant women in a Havana maternity hospital. This was the exploratory phase of a hospital-based case-control study, using January 2007-December 2009 patient records from the Eusebio Hernández University Hospital, a provincial maternity hospital in Havana. Eighty pregnant women diagnosed with pre-eclampsia and 160 controls were studied. The main variables were age, parity, nutritional status (measured by BMI), alcohol use, tobacco use, and history of pre-eclampsia in relatives of the pregnant woman (proband) or of her partner. Pearson chi square and Fisher exact test were used to assess statistical significance of associations between variables and odds ratio as a measure of association strength. Familial aggregation was studied and a case-control design used to assess gene-environment interaction, using multiplicative and additive models. Among the environmental risk factors studied, alcohol showed the strongest effect on pre-eclampsia risk (OR 3.87, 95% CI 1.64-9.13). Familial pre-eclampsia clustering was observed; risk was increased for both first-degree (OR 2.43, 95% CI 1.62-3.73) and second-degree (OR 1.89, 95% CI 1.34-2.68) relatives as well as for husband's relatives (OR 2.32, 95% CI 1.40-3.86). There was evidence of interaction between alcohol consumption and family history. Familial aggregation of the disorder was demonstrated, the first Cuban epidemiological evidence of genetic and enviromental contributions to pre-eclampsia risk. Familial clustering among the husband's relatives demonstrates the fetal genome's importance in genesis of pre-eclampsia. The interaction of environmental risk factors with genetic ones produces increased pre-eclampsia risk, compared to expectations based on independent action of these variables. KEYWORDS Pre-eclampsia, toxemia of pregnancy, pregnancy outcome, environment, genetics, genome-environment interaction, genetic epidemiology, Cuba.

Examination of association of genes in the serotonin system to autism.

PubMed

Anderson, B M; Schnetz-Boutaud, N C; Bartlett, J; Wotawa, A M; Wright, H H; Abramson, R K; Cuccaro, M L; Gilbert, J R; Pericak-Vance, M A; Haines, J L

2009-07-01

Autism is characterized as one of the pervasive developmental disorders, a spectrum of often severe behavioral and cognitive disturbances of early development. The high heritability of autism has driven multiple efforts to identify genetic variation that increases autism susceptibility. Numerous studies have suggested that variation in peripheral and central metabolism of serotonin (5-hydroxytryptamine) may play a role in the pathophysiology of autism. We screened 403 autism families for 45 single nucleotide polymorphisms in ten serotonin pathway candidate genes. Although genome-wide linkage scans in autism have provided support for linkage to various loci located within the serotonin pathway, our study does not provide strong evidence for linkage to any specific gene within the pathway. The most significant association (p = 0.0002; p = 0.02 after correcting for multiple comparisons) was found at rs1150220 (HTR3A) located on chromosome 11 ( approximately 113 Mb). To test specifically for multilocus effects, multifactor dimensionality reduction was employed, and a significant two-way interaction (p value = 0.01) was found between rs10830962, near MTNR1B (chromosome11; 92,338,075 bp), and rs1007631, near SLC7A5 (chromosome16; 86,413,596 bp). These data suggest that variation within genes on the serotonin pathway, particularly HTR3A, may have modest effects on autism risk.

Endocrine, immune, and behavioral effects of aldicarb (carbamate), atrazine (triazine) and nitrate (fertilizer) mixtures at groundwater concentrations.

PubMed

Porter, W P; Jaeger, J W; Carlson, I H

1999-01-01

This paper describes the results of 5 years of research on interactive effects of mixtures of aldicarb, atrazine, and nitrate on endocrine, immune, and nervous system function. The concentrations of chemicals used were the same order of magnitude as current maximum contaminant levels (MCLs) for all three compounds. Such levels occur in groundwater across the United States. Dosing was through voluntary consumption of drinking water. We used fractional and full factorial designs with center replicates to determine multifactor effects. We used chronic doses in experiments that varied in duration from 22 to 103 days. We tested for changes in thyroid hormone levels, ability to make antibodies to foreign proteins, and aggression in wild deer mice, Peromyscus maniculatus, and white outbred Swiss Webster mice, Mus musculus, ND4 strain. Endocrine, immune, and behavior changes occurred due to doses of mixtures, but rarely due to single compounds at the same concentrations. Immune assay data suggest the possibility of seasonal effects at low doses. We present a multiple-level model to help interpret the data in the context of human health and biological conservation concerns. We discuss six testing deficiencies of currently registered pesticides, and suggest areas of human health concerns if present trends in pesticide use continue.

PACSIN2 polymorphism is associated with thiopurine-induced hematological toxicity in children with acute lymphoblastic leukaemia undergoing maintenance therapy.

PubMed

Smid, Alenka; Karas-Kuzelicki, Natasa; Jazbec, Janez; Mlinaric-Rascan, Irena

2016-07-25

Adequate maintenance therapy for childhood acute lymphoblastic leukemia (ALL), with 6-mercaptopurine as an essential component, is necessary for retaining durable remission. Interruptions or discontinuations of the therapy due to drug-related toxicities, which can be life threatening, may result in an increased risk of relapse. In this retrospective study including 305 paediatric ALL patients undergoing maintenance therapy, we systematically investigated the individual and combined effects of genetic variants of folate pathway enzymes, as well as of polymorphisms in PACSIN2 and ITPA, on drug-induced toxicities by applying a multi-analytical approach including logistic regression (LR), classification and regression tree (CART) and generalized multifactor dimensionality reduction (GMDR). In addition to the TPMT genotype, confirmed to be a major determinant of drug related toxicities, we identified the PACSIN2 rs2413739TT genotype as being a significant risk factor for 6-MP-induced toxicity in wild-type TPMT patients. A gene-gene interaction between MTRR (rs1801394) and MTHFR (rs1801133) was detected by GMDR and proved to have an independent effect on the risk of stomatitis, as shown by LR analysis. To our knowledge, this is the first study showing PACSIN2 genotype association with hematological toxicity in ALL patients undergoing maintenance therapy.

Evaluating in Vitro Culture Medium of Gut Microbiome with Orthogonal Experimental Design and a Metaproteomics Approach.

PubMed

Li, Leyuan; Zhang, Xu; Ning, Zhibin; Mayne, Janice; Moore, Jasmine I; Butcher, James; Chiang, Cheng-Kang; Mack, David; Stintzi, Alain; Figeys, Daniel

2018-01-05

In vitro culture based approaches are time- and cost-effective solutions for rapidly evaluating the effects of drugs or natural compounds against microbiomes. The nutritional composition of the culture medium is an important determinant for effectively maintaining the gut microbiome in vitro. This study combines orthogonal experimental design and a metaproteomics approach to obtaining functional insights into the effects of different medium components on the microbiome. Our results show that the metaproteomic profile respond differently to medium components, including inorganic salts, bile salts, mucin, and short-chain fatty acids. Multifactor analysis of variance further revealed significant main and interaction effects of inorganic salts, bile salts, and mucin on the different functional groups of gut microbial proteins. While a broad regulating effect was observed on basic metabolic pathways, different medium components also showed significant modulations on cell wall, membrane, and envelope biogenesis and cell motility related functions. In particular, flagellar assembly related proteins were significantly responsive to the presence of mucin. This study provides information on the functional influences of medium components on the in vitro growth of microbiome communities and gives insight on the key components that must be considered when selecting and optimizing media for culturing ex vivo microbiotas.

Social patterns revealed through random matrix theory

NASA Astrophysics Data System (ADS)

Sarkar, Camellia; Jalan, Sarika

2014-11-01

Despite the tremendous advancements in the field of network theory, very few studies have taken weights in the interactions into consideration that emerge naturally in all real-world systems. Using random matrix analysis of a weighted social network, we demonstrate the profound impact of weights in interactions on emerging structural properties. The analysis reveals that randomness existing in particular time frame affects the decisions of individuals rendering them more freedom of choice in situations of financial security. While the structural organization of networks remains the same throughout all datasets, random matrix theory provides insight into the interaction pattern of individuals of the society in situations of crisis. It has also been contemplated that individual accountability in terms of weighted interactions remains as a key to success unless segregation of tasks comes into play.

Effects of the Caregiver Interaction Profile Training on Caregiver-Child Interactions in Dutch Child Care Centers: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Helmerhorst, Katrien O.; Riksen-Walraven, J. Marianne; Fukkink, Ruben G.; Tavecchio, Louis W. C.; Gevers Deynoot-Schaub, Mirjam J. J. M.

2017-01-01

Background: Previous studies underscore the need to improve caregiver-child interactions in early child care centers. Objective: In this study we used a randomized controlled trial to examine whether a 5-week video feedback training can improve six key interactive skills of caregivers in early child care centers: Sensitive responsiveness, respect…

Efficacy of Parent-Child Interaction Therapy with Chinese ADHD Children: Randomized Controlled Trial

ERIC Educational Resources Information Center

Leung, Cynthia; Tsang, Sandra; Ng, Gene S. H.; Choi, S. Y.

2017-01-01

Purpose: This study aimed to evaluate the efficacy of Parent-Child Interaction Therapy (PCIT) in Chinese children with attention-deficit/hyperactivity disorder (ADHD) or ADHD features. Methods: This study adopted a randomized controlled trial design without blinding. Participants were randomized into either the intervention group (n = 32) and…

Perceived Gender Presentation Among Transgender and Gender Diverse Youth: Approaches to Analysis and Associations with Bullying Victimization and Emotional Distress.

PubMed

Gower, Amy L; Rider, G Nicole; Coleman, Eli; Brown, Camille; McMorris, Barbara J; Eisenberg, Marla E

2018-06-19

As measures of birth-assigned sex, gender identity, and perceived gender presentation are increasingly included in large-scale research studies, data analysis approaches incorporating such measures are needed. Large samples capable of demonstrating variation within the transgender and gender diverse (TGD) community can inform intervention efforts to improve health equity. A population-based sample of TGD youth was used to examine associations between perceived gender presentation, bullying victimization, and emotional distress using two data analysis approaches. Secondary data analysis of the Minnesota Student Survey included 2168 9th and 11th graders who identified as "transgender, genderqueer, genderfluid, or unsure about their gender identity." Youth reported their biological sex, how others perceived their gender presentation, experiences of four forms of bullying victimization, and four measures of emotional distress. Logistic regression and multifactor analysis of variance (ANOVA) were used to compare and contrast two analysis approaches. Logistic regressions indicated that TGD youth perceived as more gender incongruent had higher odds of bullying victimization and emotional distress relative to those perceived as very congruent with their biological sex. Multifactor ANOVAs demonstrated more variable patterns and allowed for comparisons of each perceived presentation group with all other groups, reflecting nuances that exist within TGD youth. Researchers should adopt data analysis strategies that allow for comparisons of all perceived gender presentation categories rather than assigning a reference group. Those working with TGD youth should be particularly attuned to youth perceived as gender incongruent as they may be more likely to experience bullying victimization and emotional distress.

The Efficacy of Parent-Child Interaction Therapy with Chinese Families: Randomized Controlled Trial

ERIC Educational Resources Information Center

Leung, Cynthia; Tsang, Sandra; Sin, Tammy C. S.; Choi, Siu-yan

2015-01-01

Objective: This study aimed to examine the efficacy of the Parent-Child Interaction Therapy (PCIT) in Hong Kong Chinese families, using randomized controlled trial design. Methods: The participants included 111 Hong Kong Chinese parents with children aged 2--7 years old, who were randomized into the intervention group (n = 54) and control group (n…

Does Fidelity of Implementation Account for Changes in Teacher-Child Interactions in a Randomized Controlled Trial of Banking Time?

ERIC Educational Resources Information Center

LoCasale-Crouch, Jennifer; Williford, Amanda; Whittaker, Jessica; DeCoster, Jamie; Alamos, Pilar

2018-01-01

This study examined fidelity of implementation in a randomized trial of Banking Time, a classroom-based intervention intended to improve children's behavior, specifically for those at risk for developing externalizing behavior problems, through improving the quality of teacher-child interactions. The study sample comes from a randomized controlled…

Radiosonde Atmospheric Temperature Products for Assessing Climate (RATPAC): Towards a New Adjusted Radiosonde Dataset

NASA Astrophysics Data System (ADS)

Free, M. P.; Angell, J. K.; Durre, I.; Klein, S.; Lanzante, J.; Lawrimore, J.; Peterson, T.; Seidel, D.

2002-05-01

The objective of NOAA's RATPAC project is to develop climate-quality global, hemispheric and zonal upper-air temperature time series from the NCDC radiosonde database. Lanzante, Klein and Seidel (LKS) have produced an 87-station adjusted radiosonde dataset using a multifactor expert decision approach. Our goal is to extend this dataset spatially and temporally and to provide a method to update it routinely at NCDC. Since the LKS adjustment method is too labor-intensive for these purposes, we are investigating a first-difference method (Peterson et al., 1998) and an automated version of the LKS method. The first difference method (FD) can be used to combine large numbers of time series into spatial means, but also introduces a random error in the resulting large-scale averages. If the portions of the time series with suspect continuity are withheld from the calculations, it has the potential to reconstruct the real variability without the effects of the discontinuities. However, tests of FD on unadjusted radiosonde data and on reanalysis temperature data suggest that it must be used with caution when the number of stations is low and the number of data gaps is high. Because of these problems with the first difference approach, we are also considering an automated version of the LKS adjustment method using statistical change points, day-night temperature difference series, relationships between changes in adjacent atmospheric levels, and station histories to identify inhomogeneities in the temperature data.

The relationship between transformational leadership and work engagement in governmental hospitals nurses: a survey study.

PubMed

Hayati, Davood; Charkhabi, Morteza; Naami, Abdolzahra

2014-01-14

The aim of this study was to determine the effects of transformational leadership and its components on work engagement among hospital nurses. There are a few set of researches that have focused on the effects of transformational leadership on work engagement in nurses. A descriptive, correlational, cross-sectional design was used. In this study, 240 nurses have been chosen by stratified random sampling method which filled related self-reported scales include multifactor leadership questionnaire (MLQ) and work engagement scale. Data analysis has been exerted according to the statistical method of simple and multiple correlation coefficients. Findings indicated that the effect of this type of leadership on work engagement and its facets is positive and significant. In addition, the research illustrates that transformational leaders transfer their enthusiasm and high power to their subordinates by the way of modeling. This manner can increase the power as a component of work engagement in workers. Idealized influence among these leaders can result in forming a specific belief among employees toward those leaders and leaders can easily transmit their inspirational motivation to them. Consequently, it leads to make a positive vision by which, and by setting high standards, challenges the employees and establishes zeal along with optimism for attaining success in works. regarding to the results we will expand leadership and work engagement literature in hospital nurses. Also, we conclude with theoretical and practical implications and propose a clear horizon for future researches.

Is tenure justified? An experimental study of faculty beliefs about tenure, promotion, and academic freedom.

PubMed

Ceci, Stephen J; Williams, Wendy M; Mueller-Johnson, Katrin

2006-12-01

The behavioral sciences have come under attack for writings and speech that affront sensitivities. At such times, academic freedom and tenure are invoked to forestall efforts to censure and terminate jobs. We review the history and controversy surrounding academic freedom and tenure, and explore their meaning across different fields, at different institutions, and at different ranks. In a multifactoral experimental survey, 1,004 randomly selected faculty members from top-ranked institutions were asked how colleagues would typically respond when confronted with dilemmas concerning teaching, research, and wrong-doing. Full professors were perceived as being more likely to insist on having the academic freedom to teach unpopular courses, research controversial topics, and whistle-blow wrong-doing than were lower-ranked professors (even associate professors with tenure). Everyone thought that others were more likely to exercise academic freedom than they themselves were, and that promotion to full professor was a better predictor of who would exercise academic freedom than was the awarding of tenure. Few differences emerged related either to gender or type of institution, and behavioral scientists' beliefs were similar to scholars from other fields. In addition, no support was found for glib celebrations of tenure's sanctification of broadly defined academic freedoms. These findings challenge the assumption that tenure can be justified on the basis of fostering academic freedom, suggesting the need for a re-examination of the philosophical foundation and practical implications of tenure in today's academy.

[Somatic complaints, emotional awareness and maladjustment in schoolchildren].

PubMed

Ordóñez, A; Maganto, C; González, R

2015-05-01

Somatic complaints are common in childhood. Research has shown their relationship with emotional awareness and maladjustment. The study had three objectives: 1) to analyze the prevalence of somatic complaints; 2) To explore the relationships between the variables evaluated: somatic complaints, differentiating emotions, verbal sharing of emotions, not hiding emotions, body awareness, attending to others' emotions, analysis of emotions, and personal, social, family, and school maladjustments; and 3) To identify predictors of somatic complaints. The study included a total of 1,134 randomly selected schoolchildren of both sexes between 10-12 years old (M=10.99; SD=0.88). The Somatic Complaint List, Emotional Awareness Questionnaire, and Self-reported Multifactor Test of Childhood Adaptation were used to gather information. The results showed that the prevalence of somatic complaints was 90.2%, with fatigue, headache and stomachache being the most frequently. Dizziness and headache were more common in girls, and the frequency of complaints decreases with age. Somatic complaints are negatively related to emotional awareness, and positively related to maladjustment. The variables that contribute the most to the prediction of somatic complaints are personal maladjustment (25.1%) and differentiating emotions (2.5%). The study shows that personal maladjustment is the best predictor of somatic complaints; the more emotional awareness and better adapted the child, the fewer somatic complaints they lodge. Childhood is a stage with significant physical discomfort. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

Role of Sequence Variations in AhR Gene Towards Modulating Smoking Induced Lung Cancer Susceptibility in North Indian Population: A Multiple Interaction Analysis.

PubMed

Budhwar, Sneha; Bahl, Charu; Sharma, Siddharth; Singh, Navneet; Behera, Digambar

2018-05-01

AhR, a ubiquitously expressed ligand-activated transcription factor, upon its encounter with the foreign ligands activates the transcriptional machinery of genes encoding for bio-transformation enzymes like CYP1A1 hence, mediating the metabolism of Poly aromatic hydrocarbons and nitrosamines which account for the maximally found carcinogen in cigarette smoke. Polymorphic variants of AhR play a significant role and are held responsible for disposing the individuals with greater chances of acquiring lung cancer. To study the role of AhR variants (rs2282885, rs10250822, rs7811989, rs2066853) in affect-ing lung cancer susceptibility. 297 cases and 320 controls have been genotyped using PCR-RFLP technique. In order to find out the association, unconditional logistic regression approach was used. To analyze high order in-teractions Multifactor Dimensionality Reduction and Classification and regression tree was used. Subjects carrying the variant genotype for AhR rs7811989 showed a two-fold risk (p=0.007) and a marginal risk was also seen in case of individuals carrying either single or double copy of suscep-tible allele for rs102550822 (p=0.02). Whereas the variant allele for rs2066853 showcased a strong pro-tective effect (p=0.003). SQCC individuals with mutant genotype of rs2066853 also exhibited a protec-tive effect towards lung cancer (OR=0.30, p=0.0013). The association of rs7811989 mutant genotype and rs10250822 mutant genotype was evident especially in smokers as compared to non-smokers. AhR rs2066853 showed a decreased risk in smokers with mutant genotype (p=0.002). MDR approach gave the best interaction model of AhR rs2066853 and smoking (CVC=10/10, prediction error=0.42). AhR polymorphic variations can significantly contribute towards lung cancer predisposi-tion.

Contribution of susceptibility locus at HLA class I region and environmental factors to occurrence of nasopharyngeal cancer in Northeast India.

PubMed

Lakhanpal, Meena; Singh, Laishram Chandreshwor; Rahman, Tashnin; Sharma, Jagnnath; Singh, M Madhumangal; Kataki, Amal Chandra; Verma, Saurabh; Chauhan, Pradeep Singh; Singh, Y Mohan; Wajid, Saima; Kapur, Sujala; Saxena, Sunita

2015-04-01

High incidence of nasopharyngeal carcinoma (NPC) has been reported from China, Southeast Asia and Northeast (NE) region of India. Populations at geographic regions having higher incidence of NPC display human leukocyte antigen (HLA) distribution patterns different from areas having low incidence. The current study has investigated the contribution of environmental risk factors and ethnic variation of microsatellite markers in HLA region for the high incidence of NPC in NE India. Genotyping of HLA region using 33 microsatellite markers by fragment length analysis was done in 220 study subjects (120 NPC patients and 100 healthy controls). Association analysis showed two adjacent microsatellite markers HL003 (allele 121) and D6S2704 (allele 218) in the HLA class I region having association with high risk of NPC while allele 127 of HL003 and allele 255 of D6S2678 conferred a protective effect. The environmental factors mainly use of firewood (odds ratio (OR) = 3.797385, confidence interval (CI) = 1.97-7.30, P < 0), living in mud house (OR = 3.46, CI = 1.19-10.08, P = 0.022) and consumption of alcohol (OR = 2.11, CI = 1.02-4.37, P = 0.043) were found as major risk factors for NPC. Higher-order interaction showed combination of smoked food consumption and firewood use for cooking in multifactor dimensionality reduction (MDR) analysis and interaction of non-firewood users, non-ventilated houses and residence in mud houses in classification and regression tree (CART) analysis as the significant risk factors for NPC. Expression of Epstein-Barr virus (EBV) RNA was found in 92% (23/25) of NPC cases suggesting its significant role in NPC aetiopathogenesis. This study identified association of NPC with a susceptibility locus in the HLA class I region which has complex interaction with viral DNA and environmental factors.

Epistatic interactions between thiopurine methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) variations determine 6-mercaptopurine toxicity in Indian children with acute lymphoblastic leukemia.

PubMed

Dorababu, Patchva; Nagesh, Narayana; Linga, Vijay Gandhi; Gundeti, Sadashivudu; Kutala, Vijay Kumar; Reddanna, Pallu; Digumarti, Raghunadharao

2012-04-01

To explore the role of genetic variants of thiopurine methyltransferase (TPMT) and inosine triphosphate pyrophosphatase (ITPA) in 6-mercaptopurine (6-MP)-induced toxicity in Indian children with acute lymphoblastic leukemia (ALL). Children with ALL receiving 6-MP in maintenance phase of treatment (n = 90) were enrolled in the study. Bidirectional sequencing of TPMT (whole gene) and ITPA (exon 2, exon 3, and intron 2) was undertaken, and correlation between genotype and 6-MP toxicity was assessed. Five variations were observed in TPMT, including two exonic variations, TPMT*12 (374 C > T) and TPMT*3C (719A > G), and three intronic, intron 3 (12356 C > T), intron 4 (16638 C > T), and TPMT rs2842949. Two exonic, ITPA exon -2 (94 C → A) and exon 3 of ITPA (138 G > A), and one intronic, ITPA intron 2 (A→C), variations were observed in ITPA. Multifactor dimensionality reduction analysis of all the genetic variants showed independent association of ITPA 94 C→A as well as synergic epistatic interactions, i.e., TPMT*12 × ITPA ex3, ITPA ex2 × TPMT*12 × ITPA ex3, and TPMT*3C × ITPA ex2 × TPMT*12 × ITPA ex3, in determining hematological toxicity. This is further substantiated by a multiple linear regression model, which showed moderate predictability of toxicity with these variants (area under the curve = 0.70, p = 0.004). Our results suggest that apart from the individual effect of ITPA 94 C→A, epistatic interactions between the variations of TPMT (*3C, *12) and ITPA (ex2, ex3) are associated with the 6-MP toxicity. Testing these variants facilitates tailoring of the 6-MP therapy in children with ALL.

Quantitative proteomics reveals a role of JAZ7 in plant defense response to Pseudomonas syringae DC3000.

PubMed

Zhang, Tong; Meng, Li; Kong, Wenwen; Yin, Zepeng; Wang, Yang; Schneider, Jacqueline D; Chen, Sixue

2018-03-20

Jasmonate ZIM-domain (JAZ) proteins are key transcriptional repressors regulating various biological processes. Although many studies have studied JAZ proteins by genetic and biochemical analyses, little is known about JAZ7-associated global protein networks and how JAZ7 contributes to bacterial pathogen defense. In this study, we aim to fill this knowledge gap by conducting unbiased large-scale quantitative proteomics using tandem mass tags (TMT). We compared the proteomes of a JAZ7 knock-out line, a JAZ7 overexpression line, as well as the wild type Arabidopsis plants in the presence and absence of Pseudomonas syringae DC3000 infection. Both pairwise comparison and multi-factor analysis of variance reveal that differential proteins are enriched in biological processes such as primary and secondary metabolism, redox regulation, and response to stress. The differential regulation in these pathways may account for the alterations in plant size, redox homeostasis and accumulation of glucosinolates. In addition, possible interplay between genotype and environment is suggested as the abundance of seven proteins is influenced by the interaction of the two factors. Collectively, we demonstrate a role of JAZ7 in pathogen defense and provide a list of proteins that are uniquely responsive to genetic disruption, pathogen infection, or the interaction between genotypes and environmental factors. We report proteomic changes as a result of genetic perturbation of JAZ7, and the contribution of JAZ7 in plant immunity. Specifically, the similarity between the proteomes of a JAZ7 knockout mutant and the wild type plants confirmed the functional redundancy of JAZs. In contrast, JAZ7 overexpression plants were much different, and proteomic analysis of the JAZ7 overexpression plants under Pst DC3000 infection revealed that JAZ7 may regulate plant immunity via ROS modulation, energy balance and glucosinolate biosynthesis. Multiple variate analysis for this two-factor proteomics experiment suggests that protein abundance is determined by genotype, environment and the interaction between them. Copyright © 2018 Elsevier B.V. All rights reserved.

Interleukin-10 family cytokines pathway: genetic variants and psoriasis.

PubMed

Galimova, E; Rätsep, R; Traks, T; Kingo, K; Escott-Price, V; Kõks, S

2017-06-01

Interleukin (IL)-10 family cytokines IL-10, IL-19, IL-20 and IL-24 have been implicated in autoimmune diseases and we have previously reported that genetic variants in the IL10 gene cluster were associated with psoriasis. To analyse the relationship between genetic polymorphisms in the IL10 gene cluster and psoriasis. This study also explores whether there are gene-gene interactions among these genetic polymorphisms. A total of 377 patients with psoriasis and 403 matched healthy controls were enrolled to carry out a case-control study for 48 single-nucleotide polymorphisms (SNPs) of the IL10 gene cluster. Genotyping for the SNPs was conducted on the Applied Biosystems 3730 DNA Analyzer using SNPlex ® technology. Generalized multifactor dimensionality reduction (GMDR) analysis was applied to discover a likely gene-gene interaction model among the SNPs. The results showed that the allele distributions of IL10 gene cluster SNPs are significantly different between the case and control groups. Carriers of the IL10 T allele (rs1554286) and the IL20 T allele (rs1400986) conferred protection from psoriasis [odds ratio (OR) = 0·63, corrected P-value (Pc) = 0·007; OR = 0·62, Pc = 0·038, respectively]. GMDR analysis displayed a significant gene-gene interaction between IL10 (rs1554286) and IL20 (rs1518108) variants. The strongest protective effect was found with the block 1 haplotype ACATA in the IL10 gene (Pc = 0·004). This study presents a novel finding that the combination of the two SNPs, IL10 (rs1554286) and IL20 (rs1518108), is associated with a reduced risk of psoriasis. Our results indicate that genetic variants of the immunomodulatory IL10 and IL20 genes may offer a protective effect in Europeans from Russia. Independent studies are required to verify the results and find a possible functional explanation. © 2017 British Association of Dermatologists.

Microarray-based SNP genotyping to identify genetic risk factors of triple-negative breast cancer (TNBC) in South Indian population.

PubMed

Aravind Kumar, M; Singh, Vineeta; Naushad, Shaik Mohammad; Shanker, Uday; Lakshmi Narasu, M

2018-05-01

In the view of aggressive nature of Triple-Negative Breast cancer (TNBC) due to the lack of receptors (ER, PR, HER2) and high incidence of drug resistance associated with it, a case-control association study was conducted to identify the contributing genetic risk factors for Triple-negative breast cancer (TNBC). A total of 30 TNBC patients and 50 age and gender-matched controls of Indian origin were screened for 9,00,000 SNP markers using microarray-based SNP genotyping approach. The initial PLINK association analysis (p < 0.01, MAF 0.14-0.44, OR 10-24) identified 28 non-synonymous SNPs and one stop gain mutation in the exonic region as possible determinants of TNBC risk. All the 29 SNPs were annotated using ANNOVAR. The interactions between these markers were evaluated using Multifactor dimensionality reduction (MDR) analysis. The interactions were in the following order: exm408776 > exm1278309 > rs316389 > rs1651654 > rs635538 > exm1292477. Recursive partitioning analysis (RPA) was performed to construct decision tree useful in predicting TNBC risk. As shown in this analysis, rs1651654 and exm585172 SNPs are found to be determinants of TNBC risk. Artificial neural network model was used to generate the Receiver operating characteristic curves (ROC), which showed high sensitivity and specificity (AUC-0.94) of these markers. To conclude, among the 9,00,000 SNPs tested, CCDC42 exm1292477, ANXA3 exm408776, SASH1 exm585172 are found to be the most significant genetic predicting factors for TNBC. The interactions among exm408776, exm1278309, rs316389, rs1651654, rs635538, exm1292477 SNPs inflate the risk for TNBC further. Targeted analysis of these SNPs and genes alone also will have similar clinical utility in predicting TNBC.

Interactive Visual Analytics Approch for Exploration of Geochemical Model Simulations with Different Parameter Sets

NASA Astrophysics Data System (ADS)

Jatnieks, Janis; De Lucia, Marco; Sips, Mike; Dransch, Doris

2015-04-01

Many geoscience applications can benefit from testing many combinations of input parameters for geochemical simulation models. It is, however, a challenge to screen the input and output data from the model to identify the significant relationships between input parameters and output variables. For addressing this problem we propose a Visual Analytics approach that has been developed in an ongoing collaboration between computer science and geoscience researchers. Our Visual Analytics approach uses visualization methods of hierarchical horizontal axis, multi-factor stacked bar charts and interactive semi-automated filtering for input and output data together with automatic sensitivity analysis. This guides the users towards significant relationships. We implement our approach as an interactive data exploration tool. It is designed with flexibility in mind, so that a diverse set of tasks such as inverse modeling, sensitivity analysis and model parameter refinement can be supported. Here we demonstrate the capabilities of our approach by two examples for gas storage applications. For the first example our Visual Analytics approach enabled the analyst to observe how the element concentrations change around previously established baselines in response to thousands of different combinations of mineral phases. This supported combinatorial inverse modeling for interpreting observations about the chemical composition of the formation fluids at the Ketzin pilot site for CO2 storage. The results indicate that, within the experimental error range, the formation fluid cannot be considered at local thermodynamical equilibrium with the mineral assemblage of the reservoir rock. This is a valuable insight from the predictive geochemical modeling for the Ketzin site. For the second example our approach supports sensitivity analysis for a reaction involving the reductive dissolution of pyrite with formation of pyrrothite in presence of gaseous hydrogen. We determine that this reaction is thermodynamically favorable under a broad range of conditions. This includes low temperatures and absence of microbial catalysators. Our approach has potential for use in other applications that involve exploration of relationships in geochemical simulation model data.

Random vs. Combinatorial Methods for Discrete Event Simulation of a Grid Computer Network

NASA Technical Reports Server (NTRS)

Kuhn, D. Richard; Kacker, Raghu; Lei, Yu

2010-01-01

This study compared random and t-way combinatorial inputs of a network simulator, to determine if these two approaches produce significantly different deadlock detection for varying network configurations. Modeling deadlock detection is important for analyzing configuration changes that could inadvertently degrade network operations, or to determine modifications that could be made by attackers to deliberately induce deadlock. Discrete event simulation of a network may be conducted using random generation, of inputs. In this study, we compare random with combinatorial generation of inputs. Combinatorial (or t-way) testing requires every combination of any t parameter values to be covered by at least one test. Combinatorial methods can be highly effective because empirical data suggest that nearly all failures involve the interaction of a small number of parameters (1 to 6). Thus, for example, if all deadlocks involve at most 5-way interactions between n parameters, then exhaustive testing of all n-way interactions adds no additional information that would not be obtained by testing all 5-way interactions. While the maximum degree of interaction between parameters involved in the deadlocks clearly cannot be known in advance, covering all t-way interactions may be more efficient than using random generation of inputs. In this study we tested this hypothesis for t = 2, 3, and 4 for deadlock detection in a network simulation. Achieving the same degree of coverage provided by 4-way tests would have required approximately 3.2 times as many random tests; thus combinatorial methods were more efficient for detecting deadlocks involving a higher degree of interactions. The paper reviews explanations for these results and implications for modeling and simulation.

The emergence of collective phenomena in systems with random interactions

NASA Astrophysics Data System (ADS)

Abramkina, Volha

Emergent phenomena are one of the most profound topics in modern science, addressing the ways that collectivities and complex patterns appear due to multiplicity of components and simple interactions. Ensembles of random Hamiltonians allow one to explore emergent phenomena in a statistical way. In this work we adopt a shell model approach with a two-body interaction Hamiltonian. The sets of the two-body interaction strengths are selected at random, resulting in the two-body random ensemble (TBRE). Symmetries such as angular momentum, isospin, and parity entangled with complex many-body dynamics result in surprising order discovered in the spectrum of low-lying excitations. The statistical patterns exhibited in the TBRE are remarkably similar to those observed in real nuclei. Signs of almost every collective feature seen in nuclei, namely, pairing superconductivity, deformation, and vibration, have been observed in random ensembles [3, 4, 5, 6]. In what follows a systematic investigation of nuclear shape collectivities in random ensembles is conducted. The development of the mean field, its geometry, multipole collectivities and their dependence on the underlying two-body interaction are explored. Apart from the role of static symmetries such as SU(2) angular momentum and isospin groups, the emergence of dynamical symmetries including the seniority SU(2), rotational symmetry, as well as the Elliot SU(3) is shown to be an important precursor for the existence of geometric collectivities.

[New International Classification of Chronic Pancreatitis (M-ANNHEIM multifactor classification system, 2007): principles, merits, and demerits].

PubMed

Tsimmerman, Ia S

2008-01-01

The new International Classification of Chronic Pancreatitis (designated as M-ANNHEIM) proposed by a group of German specialists in late 2007 is reviewed. All its sections are subjected to analysis (risk group categories, clinical stages and phases, variants of clinical course, diagnostic criteria for "established" and "suspected" pancreatitis, instrumental methods and functional tests used in the diagnosis, evaluation of the severity of the disease using a scoring system, stages of elimination of pain syndrome). The new classification is compared with the earlier classification proposed by the author. Its merits and demerits are discussed.

[Typology and systematization of residual mental disorders in alcohol dependence].

PubMed

Klimenko, T V; Agafonova, S S

2007-01-01

The study of 85 patients with alcohol dependence appointed to forensic psychiatric expertise in the Serbsky research center of social and forensic psychiatry revealed the manifestation of polymorphic psychiatric and behavioral disorders (ICD-10 diagnosis F10.7--residual and late-onset psychotic disorders) after stopping the intoxication, withdrawal and post-withdralwal disorders. Taking into account the multifactor etiology of psychiatric disorders which are observed after ending of the direct effect of alcohol, a possibility of including other ICD-10 items to extend their diagnostics and thus provide the more accurate clinical verification of these states, is discussed.

Crop status evaluations and yield predictions

NASA Technical Reports Server (NTRS)

Haun, J. R.

1976-01-01

One phase of the large area crop inventory project is presented. Wheat yield models based on the input of environmental variables potentially obtainable through the use of space remote sensing were developed and demonstrated. By the use of a unique method for visually qualifying daily plant development and subsequent multifactor computer analyses, it was possible to develop practical models for predicting crop development and yield. Development of wheat yield prediction models was based on the discovery that morphological changes in plants are detected and quantified on a daily basis, and that this change during a portion of the season was proportional to yield.

Characteristics of group networks in the KOSPI and the KOSDAQ

NASA Astrophysics Data System (ADS)

Kim, Kyungsik; Ko, Jeung-Su; Yi, Myunggi

2012-02-01

We investigate the main feature of group networks in the KOSPI and KOSDAQ of Korean financial markets and analyze daily cross-correlations between price fluctuations for the 5-year time period from 2006 to 2010. We discuss the stabilities by undressing the market-wide effect using the Markowitz multi-factor model and the network-based approach. In particular we ascertain the explicit list of significant firms in the few largest eigenvectors from the undressed correlation matrix. Finally, we show the structure of group correlation by applying a network-based approach. In addition, the relation between market capitalizations and businesses is examined.

Logistic regression trees for initial selection of interesting loci in case-control studies

PubMed Central

Nickolov, Radoslav Z; Milanov, Valentin B

2007-01-01

Modern genetic epidemiology faces the challenge of dealing with hundreds of thousands of genetic markers. The selection of a small initial subset of interesting markers for further investigation can greatly facilitate genetic studies. In this contribution we suggest the use of a logistic regression tree algorithm known as logistic tree with unbiased selection. Using the simulated data provided for Genetic Analysis Workshop 15, we show how this algorithm, with incorporation of multifactor dimensionality reduction method, can reduce an initial large pool of markers to a small set that includes the interesting markers with high probability. PMID:18466557

Building and verifying a severity prediction model of acute pancreatitis (AP) based on BISAP, MEWS and routine test indexes.

PubMed

Ye, Jiang-Feng; Zhao, Yu-Xin; Ju, Jian; Wang, Wei

2017-10-01

To discuss the value of the Bedside Index for Severity in Acute Pancreatitis (BISAP), Modified Early Warning Score (MEWS), serum Ca2+, similarly hereinafter, and red cell distribution width (RDW) for predicting the severity grade of acute pancreatitis and to develop and verify a more accurate scoring system to predict the severity of AP. In 302 patients with AP, we calculated BISAP and MEWS scores and conducted regression analyses on the relationships of BISAP scoring, RDW, MEWS, and serum Ca2+ with the severity of AP using single-factor logistics. The variables with statistical significance in the single-factor logistic regression were used in a multi-factor logistic regression model; forward stepwise regression was used to screen variables and build a multi-factor prediction model. A receiver operating characteristic curve (ROC curve) was constructed, and the significance of multi- and single-factor prediction models in predicting the severity of AP using the area under the ROC curve (AUC) was evaluated. The internal validity of the model was verified through bootstrapping. Among 302 patients with AP, 209 had mild acute pancreatitis (MAP) and 93 had severe acute pancreatitis (SAP). According to single-factor logistic regression analysis, we found that BISAP, MEWS and serum Ca2+ are prediction indexes of the severity of AP (P-value<0.001), whereas RDW is not a prediction index of AP severity (P-value>0.05). The multi-factor logistic regression analysis showed that BISAP and serum Ca2+ are independent prediction indexes of AP severity (P-value<0.001), and MEWS is not an independent prediction index of AP severity (P-value>0.05); BISAP is negatively related to serum Ca2+ (r=-0.330, P-value<0.001). The constructed model is as follows: ln()=7.306+1.151*BISAP-4.516*serum Ca2+. The predictive ability of each model for SAP follows the order of the combined BISAP and serum Ca2+ prediction model>Ca2+>BISAP. There is no statistical significance for the predictive ability of BISAP and serum Ca2+ (P-value>0.05); however, there is remarkable statistical significance for the predictive ability using the newly built prediction model as well as BISAP and serum Ca2+ individually (P-value<0.01). Verification of the internal validity of the models by bootstrapping is favorable. BISAP and serum Ca2+ have high predictive value for the severity of AP. However, the model built by combining BISAP and serum Ca2+ is remarkably superior to those of BISAP and serum Ca2+ individually. Furthermore, this model is simple, practical and appropriate for clinical use. Copyright © 2016. Published by Elsevier Masson SAS.

Symmetry of interactions rules in incompletely connected random replicator ecosystems.

PubMed

Kärenlampi, Petri P

2014-06-01

The evolution of an incompletely connected system of species with speciation and extinction is investigated in terms of random replicators. It is found that evolving random replicator systems with speciation do become large and complex, depending on speciation parameters. Antisymmetric interactions result in large systems, whereas systems with symmetric interactions remain small. A co-dominating feature is within-species interaction pressure: large within-species interaction increases species diversity. Average fitness evolves in all systems, however symmetry and connectivity evolve in small systems only. Newcomers get extinct almost immediately in symmetric systems. The distribution in species lifetimes is determined for antisymmetric systems. The replicator systems investigated do not show any sign of self-organized criticality. The generalized Lotka-Volterra system is shown to be a tedious way of implementing the replicator system.

Interactions among irradiance, nutrients, and herbivores constrain a stream algal community.

PubMed

Rosemond, A D

1993-07-01

Using stream-side, flow-through channels, I tested for the effects of nutrients (NU) (nitrogen plus phosphorus), irradiance (L), and snail grazing (G) on a benthic algal community in a small, forested stream. Grazed communities were-dominated by a chlorophyte (basal cells ofStigeoclonium) and a cyanophyte (Chamaesiphon investiens), whereas ungrazed communities were comprised almost entirely of diatoms, regardless of nutrient and light levels. Snails maintained low algal biomass in all grazed treatments, presumably by consuming increased algal production in treatments to which L and NU were increased. When nutrients were increased, cellular nutrient content increased under ambient conditions (shaded, grazed) and biomass and productivity increased when snails were removed and light was increased. Together, nutrients and light had positive effects and grazing had negative effects on biomass (chlorophylla, AFDM, algal biovolume) and chlorophyll-and areal-specific productivity in ANOVAs. However, in most cases, only means from treatments in which all three factors were manipulated (ungrazed, +NU&L treatments) were significantly different from controls; effects of single factors were generally undetectable. These results indicate that all three factors simultaneously limited algal biomass and productivity in this stream during the summer months. Additionally, the effects of these factors in combination were in some cases different from the effects of single factors. For example, light had slight negative effects on some biomass parameters when added at ambient snail densities and nutrient concentrations, but had strong positive effects in conjunction with nutrient addition and snail removal. This study demonstrates that algal biomass and productivity can be under multiple constraints by irradiance, nutrients, and herbivores and indicates the need to employ multifactor experiments to test for such interactive effects.

The central role of AMP-kinase and energy homeostasis impairment in Alzheimer's disease: a multifactor network analysis.

PubMed

Caberlotto, Laura; Lauria, Mario; Nguyen, Thanh-Phuong; Scotti, Marco

2013-01-01

Alzheimer's disease is the most common cause of dementia worldwide, affecting the elderly population. It is characterized by the hallmark pathology of amyloid-β deposition, neurofibrillary tangle formation, and extensive neuronal degeneration in the brain. Wealth of data related to Alzheimer's disease has been generated to date, nevertheless, the molecular mechanism underlying the etiology and pathophysiology of the disease is still unknown. Here we described a method for the combined analysis of multiple types of genome-wide data aimed at revealing convergent evidence interest that would not be captured by a standard molecular approach. Lists of Alzheimer-related genes (seed genes) were obtained from different sets of data on gene expression, SNPs, and molecular targets of drugs. Network analysis was applied for identifying the regions of the human protein-protein interaction network showing a significant enrichment in seed genes, and ultimately, in genes associated to Alzheimer's disease, due to the cumulative effect of different combinations of the starting data sets. The functional properties of these enriched modules were characterized, effectively considering the role of both Alzheimer-related seed genes and genes that closely interact with them. This approach allowed us to present evidence in favor of one of the competing theories about AD underlying processes, specifically evidence supporting a predominant role of metabolism-associated biological process terms, including autophagy, insulin and fatty acid metabolic processes in Alzheimer, with a focus on AMP-activated protein kinase. This central regulator of cellular energy homeostasis regulates a series of brain functions altered in Alzheimer's disease and could link genetic perturbation with neuronal transmission and energy regulation, representing a potential candidate to be targeted by therapy.

Epistatic effect of plasminogen activator inhibitor 1 and beta-fibrinogen genes on risk of glomerular microthrombosis in lupus nephritis: interaction with environmental/clinical factors.

PubMed

Gong, Rujun; Liu, Zhihong; Li, Leishi

2007-05-01

Glomerular microthrombosis (GMT) is not uncommon in lupus nephritis and has been associated with active renal injury and progressive kidney destruction. We undertook this study to determine whether genetic variations of hemostasis factors, such as plasminogen activator inhibitor 1 (PAI-1) and fibrinogen, affect the risk of GMT. A cross-sectional cohort of 101 lupus nephritis patients with or without GMT was genotyped for PAI-1 -675 4G/5G and beta-fibrinogen (FGB) -455 G/A gene polymorphisms and analyzed. PAI-1 4G/4G homozygotes and FGB A allele carriers were both at increased risk for GMT. When the data were stratified for both gene polymorphisms, an epistatic effect was detected. The PAI-1 4G/4G genotype was found to predispose to GMT not equally in all lupus nephritis patients, but only in FGB A allele carriers. Likewise, the association between the FGB A allele and GMT was restricted to lupus nephritis patients homozygous for the PAI-1 4G allele. This epistatic effect was revalidated by the multifactor dimensionality reduction (MDR) analysis and further assessed by incorporating a variety of environmental and clinical factors into the MDR analysis. The most parsimonious model that had a cross-validation consistency of 100% included joint effects of PAI-1 and FGB gene polymorphisms and anticardiolipin antibody (aCL) status and yielded the best prediction of GMT, with 66.6% accuracy. Our findings suggest that risk of GMT in lupus nephritis is attributable, at least in part, to an epistatic effect of PAI-1 and FGB genes, likely via an interaction with environmental/clinical factors, such as aCL.

Molecular insights into the association of obesity with breast cancer risk: relevance to xenobiotic metabolism and CpG island methylation of tumor suppressor genes.

PubMed

Naushad, Shaik Mohammad; Hussain, Tajamul; Al-Attas, Omar S; Prayaga, Aruna; Digumarti, Raghunadha Rao; Gottumukkala, Suryanarayana Raju; Kutala, Vijay Kumar

2014-07-01

Obesity, genetic polymorphisms of xenobiotic metabolic pathway, hypermethylation of tumor suppressor genes, and hypomethylation of proapoptotic genes are known to be independent risk factors for breast cancer. The objective of this study is to evaluate the combined effect of these environmental, genetic, and epigenetic risk factors on the susceptibility to breast cancer. PCR-RFLP and multiplex PCR were used for the genetic analysis of six variants of xenobiotic metabolic pathway. Methylation-specific PCR was used for the epigenetic analysis of four genetic loci. Multifactor dimensionality reduction analysis revealed a significant interaction between the body mass index (BMI) and catechol-O-methyl transferase H108L variant alone or in combination with cytochrome P450 (CYP) 1A1m1 variant. Women with "Luminal A" breast cancer phenotype had higher BMI compared to other phenotypes and healthy controls. There was no association between the BMI and tumor grade. The post-menopausal obese women exhibited lower glutathione levels. BMI showed a positive association with the methylation of extracellular superoxide dismutase (r = 0.21, p < 0.05), Ras-association (RalGDS/AF-6) domain family member 1 (RASSF1A) (r = 0.31, p < 0.001), and breast cancer type 1 susceptibility protein (r = 0.19, p < 0.05); and inverse association with methylation of BNIP3 (r = -0.48, p < 0.0001). To conclude based on these results, obesity increases the breast cancer susceptibility by two possible mechanisms: (i) by interacting with xenobiotic genetic polymorphisms in inducing increased oxidative DNA damage and (ii) by altering the methylome of several tumor suppressor genes.

CYP1A1, GCLC, AGT, AGTR1 gene-gene interactions in community-acquired pneumonia pulmonary complications.

PubMed

Salnikova, Lyubov E; Smelaya, Tamara V; Golubev, Arkadiy M; Rubanovich, Alexander V; Moroz, Viktor V

2013-11-01

This study was conducted to establish the possible contribution of functional gene polymorphisms in detoxification/oxidative stress and vascular remodeling pathways to community-acquired pneumonia (CAP) susceptibility in the case-control study (350 CAP patients, 432 control subjects) and to predisposition to the development of CAP complications in the prospective study. All subjects were genotyped for 16 polymorphic variants in the 14 genes of xenobiotics detoxification CYP1A1, AhR, GSTM1, GSTT1, ABCB1, redox-status SOD2, CAT, GCLC, and vascular homeostasis ACE, AGT, AGTR1, NOS3, MTHFR, VEGFα. Risk of pulmonary complications (PC) in the single locus analysis was associated with CYP1A1, GCLC and AGTR1 genes. Extra PC (toxic shock syndrome and myocarditis) were not associated with these genes. We evaluated gene-gene interactions using multi-factor dimensionality reduction, and cumulative gene risk score approaches. The final model which included >5 risk alleles in the CYP1A1 (rs2606345, rs4646903, rs1048943), GCLC, AGT, and AGTR1 genes was associated with pleuritis, empyema, acute respiratory distress syndrome, all PC and acute respiratory failure (ARF). We considered CYP1A1, GCLC, AGT, AGTR1 gene set using Set Distiller mode implemented in GeneDecks for discovering gene-set relations via the degree of sharing descriptors within a given gene set. N-acetylcysteine and oxygen were defined by Set Distiller as the best descriptors for the gene set associated in the present study with PC and ARF. Results of the study are in line with literature data and suggest that genetically determined oxidative stress exacerbation may contribute to the progression of lung inflammation.

Structure of local interactions in complex financial dynamics

PubMed Central

Jiang, X. F.; Chen, T. T.; Zheng, B.

2014-01-01

With the network methods and random matrix theory, we investigate the interaction structure of communities in financial markets. In particular, based on the random matrix decomposition, we clarify that the local interactions between the business sectors (subsectors) are mainly contained in the sector mode. In the sector mode, the average correlation inside the sectors is positive, while that between the sectors is negative. Further, we explore the time evolution of the interaction structure of the business sectors, and observe that the local interaction structure changes dramatically during a financial bubble or crisis. PMID:24936906

[Clinical characteristics and prognostic factors of pulmonary tuberculosis with concurrent lung cancer].

PubMed

Gu, Yingchun; Song, Yelin; Liu, Yufeng

2014-09-30

To explore the clinical characteristics and prognostic factors of pulmonary tuberculosis with concurrent lung cancer. Comprehensive analyses were conducted for 58 cases of pulmonary tuberculosis patients with lung cancer. Their clinical symptoms, signs and imaging results were analyzed between January 1998 and January 2005 at Qingdao Chest Hospital. Kaplan-Meier method was utilized to calculate their survival rates. Nine prognostic characteristics were analyzed. Single factor analysis was performed with Logrank test and multi-factor analysis with Cox regression model. The initial symptoms were cough, chest tightness, fever and hemoptysis. Chest radiology showed the coexistence of two diseases was 36 in the same lobe and 22 in different lobes. And there were pulmonary nodules (n = 24), cavities (n = 19), infiltration (n = 8) and atelectasis (n = 7). According to the pathological characteristics, there were squamous carcinoma (n = 33), adenocarcinoma (n = 17), small cell carcinoma (n = 4) and unidentified (n = 4) respectively. The TNM stages were I (n = 13), II(n = 22), III (n = 16) and IV (n = 7) respectively. The median survival period was 24 months. And the 1, 3, 5-year survival rates were 65.5%, 65.5% and 29.0% respectively. Single factor analysis showed that lung cancer TNM staging (P = 0.000) and tuberculosis activity (P = 0.024) were significantly associated with patient prognosis. And multi-factor analysis showed that lung cancer TNM staging (RR = 2.629, 95%CI: 1.759-3.928, P = 0.000) and tuberculosis activity (RR = 1.885, 95%CI: 1.023-3.471, P = 0.042) were relatively independent prognostic factors. The clinical and radiological characteristics contribute jointly to early diagnosis and therapy of tuberculosis with concurrent lung cancer. And TNM staging of lung cancer and activity of tuberculosis are major prognostic factors.

Risk factors associated with sporadic salmonellosis in adults: a case-control study.

PubMed

Ziehm, D; Dreesman, J; Campe, A; Kreienbrock, L; Pulz, M

2013-02-01

In order to identify and assess recent risk factors for sporadic human infections with Salmonella enterica, we conducted a case-control study in Lower Saxony, Germany. The data collection was based on standardized telephone interviews with 1017 cases and 346 controls aged >14 years. Odds ratios were calculated in single-factor and multi-factor analyses for Salmonella cases and two different control groups, i.e. population controls and controls with rotavirus infection. Multi-factor analysis revealed associations between sporadic Salmonella infections for two exposures by both sets of controls: consumption of raw ground pork [adjusted odds ratio (aOR) 2·38, 95% confidence interval (CI) 1·27-4·44] and foreign travel (aOR 2·12, 95% CI 1·00-4·52). Other exposures included consumption of food items containing eggs (aOR 1·43, 95% CI 0·80-2·54), consumption of chicken meat (aOR 1·77, 95% CI 1·26-2·50), outdoor meals/barbecues (aOR 3·96, 95% CI 1·41-11·12) and taking gastric acidity inhibitors (aOR 2·42, 95% CI 1·19-4·92), all were significantly associated with respect to one of the two control groups. The impact of consuming food items containing eggs or chicken meat was lower than expected from the literature. This might be a consequence of Salmonella control programmes as well as increased public awareness of eggs and chicken products being a risk factor for salmonellosis. Efforts to reduce Salmonella infections due to raw pork products should be intensified.

The Multifactor Measure of Performance: Its Development, Norming, and Validation.

PubMed

Bar-On, Reuven

2018-01-01

This article describes the development as well as the initial norming and validation of the Multifactor Measure of Performance™ (MMP™), which is a psychometric instrument that is designed to study, assess and enhance key predictors of human performance to help individuals perform at a higher level. It was created by the author, for the purpose of going beyond existing conceptual and psychometric models that often focus on relatively few factors that are purported to assess performance at school, in the workplace and elsewhere. The relative sparsity of multifactorial pre-employment assessment instruments exemplifies, for the author, one of the important reasons for developing the MMP™, which attempts to comprehensively evaluate a wider array of factors that are thought to contribute to performance. In that this situation creates a need in the area of test-construction that should be addressed, the author sought to develop a multifactorial assessment and development instrument that could concomitantly evaluate a combination of physical, cognitive, intra-personal, inter-personal, and motivational factors that significantly contribute to performance. The specific aim of this article is to show why, how and if this could be done as well as to present and discuss the potential importance of the results obtained to date. The findings presented here will hopefully add to what is known about human performance and thus contribute to the professional literature, in addition to contribute to the continued development of the MMP™. The impetus for developing the MMP™ is first explained below, followed by a detailed description of the process involved and the findings obtained; and their potential application is then discussed as well as the possible limitations of the present research and the need for future studies to address them.

Surgeons' Leadership Styles and Team Behavior in the Operating Room.

PubMed

Hu, Yue-Yung; Parker, Sarah Henrickson; Lipsitz, Stuart R; Arriaga, Alexander F; Peyre, Sarah E; Corso, Katherine A; Roth, Emilie M; Yule, Steven J; Greenberg, Caprice C

2016-01-01

The importance of leadership is recognized in surgery, but the specific impact of leadership style on team behavior is not well understood. In other industries, leadership is a well-characterized construct. One dominant theory proposes that transactional (task-focused) leaders achieve minimum standards and transformational (team-oriented) leaders inspire performance beyond expectations. We videorecorded 5 surgeons performing complex operations. Each surgeon was scored on the Multifactor Leadership Questionnaire, a validated method for scoring transformational and transactional leadership style, by an organizational psychologist and a surgeon researcher. Independent coders assessed surgeons' leadership behaviors according to the Surgical Leadership Inventory and team behaviors (information sharing, cooperative, and voice behaviors). All coders were blinded. Leadership style (Multifactor Leadership Questionnaire) was correlated with surgeon behavior (Surgical Leadership Inventory) and team behavior using Poisson regression, controlling for time and the total number of behaviors, respectively. All surgeons scored similarly on transactional leadership (range 2.38 to 2.69), but varied more widely on transformational leadership (range 1.98 to 3.60). Each 1-point increase in transformational score corresponded to 3 times more information-sharing behaviors (p < 0.0001) and 5.4 times more voice behaviors (p = 0.0005) among the team. With each 1-point increase in transformational score, leaders displayed 10 times more supportive behaviors (p < 0.0001) and displayed poor behaviors 12.5 times less frequently (p < 0.0001). Excerpts of representative dialogue are included for illustration. We provide a framework for evaluating surgeons' leadership and its impact on team performance in the operating room. As in other fields, our data suggest that transformational leadership is associated with improved team behavior. Surgeon leadership development, therefore, has the potential to improve the efficiency and safety of operative care. Copyright © 2016 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Multi-Factor Impact Analysis of Agricultural Production in Bangladesh with Climate Change

NASA Technical Reports Server (NTRS)

Ruane, Alex C.; Major, David C.; Yu, Winston H.; Alam, Mozaharul; Hussain, Sk. Ghulam; Khan, Abu Saleh; Hassan, Ahmadul; Al Hossain, Bhuiya Md. Tamim; Goldberg, Richard; Horton, Radley M.;

The Multifactor Measure of Performance: Its Development, Norming, and Validation

PubMed Central

Bar-On, Reuven

2018-01-01

This article describes the development as well as the initial norming and validation of the Multifactor Measure of Performance™ (MMP™)1, which is a psychometric instrument that is designed to study, assess and enhance key predictors of human performance to help individuals perform at a higher level. It was created by the author, for the purpose of going beyond existing conceptual and psychometric models that often focus on relatively few factors that are purported to assess performance at school, in the workplace and elsewhere. The relative sparsity of multifactorial pre-employment assessment instruments exemplifies, for the author, one of the important reasons for developing the MMP™, which attempts to comprehensively evaluate a wider array of factors that are thought to contribute to performance. In that this situation creates a need in the area of test-construction that should be addressed, the author sought to develop a multifactorial assessment and development instrument that could concomitantly evaluate a combination of physical, cognitive, intra-personal, inter-personal, and motivational factors that significantly contribute to performance. The specific aim of this article is to show why, how and if this could be done as well as to present and discuss the potential importance of the results obtained to date. The findings presented here will hopefully add to what is known about human performance and thus contribute to the professional literature, in addition to contribute to the continued development of the MMP™. The impetus for developing the MMP™ is first explained below, followed by a detailed description of the process involved and the findings obtained; and their potential application is then discussed as well as the possible limitations of the present research and the need for future studies to address them. PMID:29515479

Random forests of interaction trees for estimating individualized treatment effects in randomized trials.

PubMed

Su, Xiaogang; Peña, Annette T; Liu, Lei; Levine, Richard A

2018-04-29

Assessing heterogeneous treatment effects is a growing interest in advancing precision medicine. Individualized treatment effects (ITEs) play a critical role in such an endeavor. Concerning experimental data collected from randomized trials, we put forward a method, termed random forests of interaction trees (RFIT), for estimating ITE on the basis of interaction trees. To this end, we propose a smooth sigmoid surrogate method, as an alternative to greedy search, to speed up tree construction. The RFIT outperforms the "separate regression" approach in estimating ITE. Furthermore, standard errors for the estimated ITE via RFIT are obtained with the infinitesimal jackknife method. We assess and illustrate the use of RFIT via both simulation and the analysis of data from an acupuncture headache trial. Copyright © 2018 John Wiley & Sons, Ltd.

WWC Review of the Report "Interactive Learning Online at Public Universities: Evidence from a Six-Campus Randomized Trial." What Works Clearinghouse Single Study Review

ERIC Educational Resources Information Center

What Works Clearinghouse, 2014

2014-01-01

The 2013 study, "Interactive Learning Online at Public Universities: Evidence From a Six-Campus Randomized Trial," examined the impact of interactive learning online (ILO) on the pass rates of 605 students enrolled in introductory statistics courses at six public universities. ILO is a form of online course instruction in which…

Pre-drilling prediction techniques on the high-temperature high-pressure hydrocarbon reservoirs offshore Hainan Island, China

NASA Astrophysics Data System (ADS)

Zhang, Hanyu; Liu, Huaishan; Wu, Shiguo; Sun, Jin; Yang, Chaoqun; Xie, Yangbing; Chen, Chuanxu; Gao, Jinwei; Wang, Jiliang

2018-02-01

Decreasing the risks and geohazards associated with drilling engineering in high-temperature high-pressure (HTHP) geologic settings begins with the implementation of pre-drilling prediction techniques (PPTs). To improve the accuracy of geopressure prediction in HTHP hydrocarbon reservoirs offshore Hainan Island, we made a comprehensive summary of current PPTs to identify existing problems and challenges by analyzing the global distribution of HTHP hydrocarbon reservoirs, the research status of PPTs, and the geologic setting and its HTHP formation mechanism. Our research results indicate that the HTHP formation mechanism in the study area is caused by multiple factors, including rapid loading, diapir intrusions, hydrocarbon generation, and the thermal expansion of pore fluids. Due to this multi-factor interaction, a cloud of HTHP hydrocarbon reservoirs has developed in the Ying-Qiong Basin, but only traditional PPTs have been implemented, based on the assumption of conditions that do not conform to the actual geologic environment, e.g., Bellotti's law and Eaton's law. In this paper, we focus on these issues, identify some challenges and solutions, and call for further PPT research to address the drawbacks of previous works and meet the challenges associated with the deepwater technology gap. In this way, we hope to contribute to the improved accuracy of geopressure prediction prior to drilling and provide support for future HTHP drilling offshore Hainan Island.

Age-Based Differences in the Genetic Determinants of Glycemic Control: A Case of FOXO3 Variations.

PubMed

Sun, Liang; Hu, Caiyou; Qian, Yu; Zheng, Chenguang; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, Keyan; Huang, Jin; Zhou, Qin; Yang, Ze

2015-01-01

Glucose homeostasis is a trait of healthy ageing and is crucial to the elderly, but less consideration has been given to the age composition in most studies involving genetics and hyperglycemia. Seven variants in FOXO3 were genotyped in three cohorts (n = 2037; LLI, MI_S and MI_N; mean age: 92.5 ± 3.6, 45.9 ± 8.2 and 46.8 ± 10.3, respectively) to compare the contribution of FOXO3 to fasting hyperglycemia (FH) between long-lived individuals (LLI, aged over 90 years) and middle-aged subjects (aged from 35-65 years). A different genetic predisposition of FOXO3 alleles to FH was observed between LLI and both of two middle-aged cohorts. In the LLI cohort, the longevity beneficial alleles of three variants with the haplotype "AGGC" in block 1 were significantly protective to FH, fasting glucose, hemoglobin A1C and HOMA-IR. Notably, combining multifactor dimensionality reduction and logistic regression, we identified a significant 3-factor interaction model (rs2802288, rs2802292 and moderate physical activity) associated with lower FH risk. However, not all of the findings were replicated in the two middle-aged cohorts. Our data provides a novel insight into the inconsistent genetic determinants between middle-aged and LLI subjects. FOXO3 might act as a shared genetic predisposition to hyperglycemia and lifespan.

Age-Based Differences in the Genetic Determinants of Glycemic Control: A Case of FOXO3 Variations

PubMed Central

Sun, Liang; Hu, Caiyou; Qian, Yu; Zheng, Chenguang; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, Keyan; Huang, Jin; Zhou, Qin; Yang, Ze

2015-01-01

Background Glucose homeostasis is a trait of healthy ageing and is crucial to the elderly, but less consideration has been given to the age composition in most studies involving genetics and hyperglycemia. Methods Seven variants in FOXO3 were genotyped in three cohorts (n = 2037; LLI, MI_S and MI_N; mean age: 92.5±3.6, 45.9±8.2 and 46.8±10.3, respectively) to compare the contribution of FOXO3 to fasting hyperglycemia (FH) between long-lived individuals (LLI, aged over 90 years) and middle-aged subjects (aged from 35–65 years). Results A different genetic predisposition of FOXO3 alleles to FH was observed between LLI and both of two middle-aged cohorts. In the LLI cohort, the longevity beneficial alleles of three variants with the haplotype “AGGC” in block 1 were significantly protective to FH, fasting glucose, hemoglobin A1C and HOMA-IR. Notably, combining multifactor dimensionality reduction and logistic regression, we identified a significant 3-factor interaction model (rs2802288, rs2802292 and moderate physical activity) associated with lower FH risk. However, not all of the findings were replicated in the two middle-aged cohorts. Conclusion Our data provides a novel insight into the inconsistent genetic determinants between middle-aged and LLI subjects. FOXO3 might act as a shared genetic predisposition to hyperglycemia and lifespan. PMID:25993007

Interrelationship of Cytokines, Hypothalamic-Pituitary-Adrenal Axis Hormones, and Psychosocial Variables in the Prediction of Preterm Birth

PubMed Central

Pearce, B.D.; Grove, J.; Bonney, E.A.; Bliwise, N.; Dudley, D.J.; Schendel, D.E.; Thorsen, P.

2010-01-01

Background/Aims To examine the relationship of biological mediators (cytokines, stress hormones), psychosocial, obstetric history, and demographic factors in the early prediction of preterm birth (PTB) using a comprehensive logistic regression model incorporating diverse risk factors. Methods In this prospective case-control study, maternal serum biomarkers were quantified at 9–23 weeks’ gestation in 60 women delivering at <37 weeks compared to 123 women delivering at term. Biomarker data were combined with maternal sociodemographic factors and stress data into regression models encompassing 22 preterm risk factors and 1st-order interactions. Results Among individual biomarkers, we found that macrophage migration inhibitory factor (MIF), interleukin-10, C-reactive protein (CRP), and tumor necrosis factor-α were statistically significant predictors of PTB at all cutoff levels tested (75th, 85th, and 90th percentiles). We fit multifactor models for PTB prediction at each biomarker cutoff. Our best models revealed that MIF, CRP, risk-taking behavior, and low educational attainment were consistent predictors of PTB at all biomarker cutoffs. The 75th percentile cutoff yielded the best predicting model with an area under the ROC curve of 0.808 (95% CI 0.743–0.874). Conclusion Our comprehensive models highlight the prominence of behavioral risk factors for PTB and point to MIF as a possible psychobiological mediator. PMID:20160447

Warming reduces carbon losses from grassland exposed to elevated atmospheric carbon dioxide.

PubMed

Pendall, Elise; Heisler-White, Jana L; Williams, David G; Dijkstra, Feike A; Carrillo, Yolima; Morgan, Jack A; Lecain, Daniel R

2013-01-01

The flux of carbon dioxide (CO2) between terrestrial ecosystems and the atmosphere may ameliorate or exacerbate climate change, depending on the relative responses of ecosystem photosynthesis and respiration to warming temperatures, rising atmospheric CO2, and altered precipitation. The combined effect of these global change factors is especially uncertain because of their potential for interactions and indirectly mediated conditions such as soil moisture. Here, we present observations of CO2 fluxes from a multi-factor experiment in semi-arid grassland that suggests a potentially strong climate - carbon cycle feedback under combined elevated [CO2] and warming. Elevated [CO2] alone, and in combination with warming, enhanced ecosystem respiration to a greater extent than photosynthesis, resulting in net C loss over four years. The effect of warming was to reduce respiration especially during years of below-average precipitation, by partially offsetting the effect of elevated [CO2] on soil moisture and C cycling. Carbon losses were explained partly by stimulated decomposition of soil organic matter with elevated [CO2]. The climate - carbon cycle feedback observed in this semiarid grassland was mediated by soil water content, which was reduced by warming and increased by elevated [CO2]. Ecosystem models should incorporate direct and indirect effects of climate change on soil water content in order to accurately predict terrestrial feedbacks and long-term storage of C in soil.

Multilocus family-based association analysis of seven candidate polymorphisms with essential hypertension in an african-derived semi-isolated brazilian population.

PubMed

Kimura, L; Angeli, C B; Auricchio, M T B M; Fernandes, G R; Pereira, A C; Vicente, J P; Pereira, T V; Mingroni-Netto, R C

2012-01-01

Background. It has been widely suggested that analyses considering multilocus effects would be crucial to characterize the relationship between gene variability and essential hypertension (EH). Objective. To test for the presence of multilocus effects between/among seven polymorphisms (six genes) on blood pressure-related traits in African-derived semi-isolated Brazilian populations (quilombos). Methods. Analyses were carried out using a family-based design in a sample of 652 participants (97 families). Seven variants were investigated: ACE (rs1799752), AGT (rs669), ADD2 (rs3755351), NOS3 (rs1799983), GNB3 (rs5441 and rs5443), and GRK4 (rs1801058). Sensitivity analyses were further performed under a case-control design with unrelated participants only. Results. None of the investigated variants were associated individually with both systolic and diastolic BP levels (SBP and DBP, respectively) or EH (as a binary outcome). Multifactor dimensionality reduction-based techniques revealed a marginal association of the combined effect of both GNB3 variants on DBP levels in a family-based design (P = 0.040), whereas a putative NOS3-GRK4 interaction also in relation to DBP levels was observed in the case-control design only (P = 0.004). Conclusion. Our results provide limited support for the hypothesis of multilocus effects between/among the studied variants on blood pressure in quilombos. Further larger studies are needed to validate our findings.

Microbial contributions to climate change through carbon cycle feedbacks.

PubMed

Bardgett, Richard D; Freeman, Chris; Ostle, Nicholas J

2008-08-01

There is considerable interest in understanding the biological mechanisms that regulate carbon exchanges between the land and atmosphere, and how these exchanges respond to climate change. An understanding of soil microbial ecology is central to our ability to assess terrestrial carbon cycle-climate feedbacks, but the complexity of the soil microbial community and the many ways that it can be affected by climate and other global changes hampers our ability to draw firm conclusions on this topic. In this paper, we argue that to understand the potential negative and positive contributions of soil microbes to land-atmosphere carbon exchange and global warming requires explicit consideration of both direct and indirect impacts of climate change on microorganisms. Moreover, we argue that this requires consideration of complex interactions and feedbacks that occur between microbes, plants and their physical environment in the context of climate change, and the influence of other global changes which have the capacity to amplify climate-driven effects on soil microbes. Overall, we emphasize the urgent need for greater understanding of how soil microbial ecology contributes to land-atmosphere carbon exchange in the context of climate change, and identify some challenges for the future. In particular, we highlight the need for a multifactor experimental approach to understand how soil microbes and their activities respond to climate change and consequences for carbon cycle feedbacks.

[A novel posturographic method to differentiate sway patterns of patients with Parkinson's disease from patients with cerebellar ataxia].

PubMed

Schwesig, René; Becker, Stephan; Lauenroth, Andreas; Kluttig, Alexander; Leuchte, Siegfried; Esperer, Hans Dieter

2009-12-01

Nigrostriatal and cerebellar systems are important postural subsystems in neurologic rehabilitation. In this study, we investigated the ability to differentiate both systems via posturography and spectral analysis. This cross-sectional study included 156 study subjects with 52 individuals in each group (healthy controls, Parkinson's disease and cerebellar disease patients). The mean age of all groups was 61.3+/-13.4 years. We used the interactive balance system (IBS) to differentiate vertical pressure fluctuations on four independent force plates, each supporting one heel or the toes of each leg in eight test positions. We also performed a frequency analysis of the force/time signal. The univariate, multifactor covariance analysis was used for statistical evaluation. Variance analysis of the Parkinson's group (mean/95% CI: 23.0/20.5-25.5) and control group (mean/95% CI: 16.7/14.2-19.2) revealed the greatest differences in frequency range F1. Subjects with cerebellar disease showed significant differences compared with controls in all frequency ranges. Furthermore, cerebellar disease subjects showed a consistently lower postural stability compared with the Parkinson's (p<0.001) and control groups (p<0.001). Results from the present study suggest that the cerebellar and nigrostriatal system can be effectively differentiated and assessed with frequency-analyzed posturographic parameters. Furthermore, the IBS allows a highly practical differential assessment in neurologic rehabilitation.

Impact of leadership styles adopted by head nurses on job satisfaction: a comparative study between governmental and private hospitals in Jordan.

PubMed

Abdelhafiz, Ibrahim Mbarak; Alloubani, Aladeen Mah'D; Almatari, Mohammad

2016-04-01

Previous studies demonstrated that leadership styles are the basis of daily interactions between leaders and employees and facilitate and enhance work processes. This study aimed to explore how the leadership styles of nurse leaders affect job satisfaction among working nurses. Quantitative, descriptive and comparative methods were used. Three main Ministry of Health hospitals in different areas of Jordan and three private hospitals in Amman were selected. Among the leadership styles measured by the Multi-factor Leadership Questionnaire 5X, transformational leadership had been used by head nurse managers in both settings more than transactional leadership and passive-avoidant leadership. The level of job satisfaction among nursing staff was higher in public hospitals than in private hospitals in this study. A positive relationship was found between the overall score for transformational leadership and job satisfaction (r = 0.374**). The overall transactional leadership score correlated positively with job satisfaction (r = 0.391**). Conversely, the overall correlation between passive-avoidant leadership and job satisfaction was negative (r = -0.240). The increased development of transformational leadership behaviours increases nurses' job satisfaction and thus contributes to an increased retention of nurses. The ability of hospitals to address the leadership styles of head nurses and their impacts on job satisfaction will be strengthened. © 2015 John Wiley & Sons Ltd.

Warming Reduces Carbon Losses from Grassland Exposed to Elevated Atmospheric Carbon Dioxide

PubMed Central

Pendall, Elise; Heisler-White, Jana L.; Williams, David G.; Dijkstra, Feike A.; Carrillo, Yolima; Morgan, Jack A.; LeCain, Daniel R.

2013-01-01

The flux of carbon dioxide (CO2) between terrestrial ecosystems and the atmosphere may ameliorate or exacerbate climate change, depending on the relative responses of ecosystem photosynthesis and respiration to warming temperatures, rising atmospheric CO2, and altered precipitation. The combined effect of these global change factors is especially uncertain because of their potential for interactions and indirectly mediated conditions such as soil moisture. Here, we present observations of CO2 fluxes from a multi-factor experiment in semi-arid grassland that suggests a potentially strong climate – carbon cycle feedback under combined elevated [CO2] and warming. Elevated [CO2] alone, and in combination with warming, enhanced ecosystem respiration to a greater extent than photosynthesis, resulting in net C loss over four years. The effect of warming was to reduce respiration especially during years of below-average precipitation, by partially offsetting the effect of elevated [CO2] on soil moisture and C cycling. Carbon losses were explained partly by stimulated decomposition of soil organic matter with elevated [CO2]. The climate – carbon cycle feedback observed in this semiarid grassland was mediated by soil water content, which was reduced by warming and increased by elevated [CO2]. Ecosystem models should incorporate direct and indirect effects of climate change on soil water content in order to accurately predict terrestrial feedbacks and long-term storage of C in soil. PMID:23977180

Interrelationship of cytokines, hypothalamic-pituitary-adrenal axis hormones, and psychosocial variables in the prediction of preterm birth.

PubMed

Pearce, B D; Grove, J; Bonney, E A; Bliwise, N; Dudley, D J; Schendel, D E; Thorsen, P

2010-01-01

To examine the relationship of biological mediators (cytokines, stress hormones), psychosocial, obstetric history, and demographic factors in the early prediction of preterm birth (PTB) using a comprehensive logistic regression model incorporating diverse risk factors. In this prospective case-control study, maternal serum biomarkers were quantified at 9-23 weeks' gestation in 60 women delivering at <37 weeks compared to 123 women delivering at term. Biomarker data were combined with maternal sociodemographic factors and stress data into regression models encompassing 22 preterm risk factors and 1st-order interactions. Among individual biomarkers, we found that macrophage migration inhibitory factor (MIF), interleukin-10, C-reactive protein (CRP), and tumor necrosis factor-alpha were statistically significant predictors of PTB at all cutoff levels tested (75th, 85th, and 90th percentiles). We fit multifactor models for PTB prediction at each biomarker cutoff. Our best models revealed that MIF, CRP, risk-taking behavior, and low educational attainment were consistent predictors of PTB at all biomarker cutoffs. The 75th percentile cutoff yielded the best predicting model with an area under the ROC curve of 0.808 (95% CI 0.743-0.874). Our comprehensive models highlight the prominence of behavioral risk factors for PTB and point to MIF as a possible psychobiological mediator. Copyright (c) 2010 S. Karger AG, Basel.

Predicting protein functions from redundancies in large-scale protein interaction networks

NASA Technical Reports Server (NTRS)

Samanta, Manoj Pratim; Liang, Shoudan

2003-01-01

Interpreting data from large-scale protein interaction experiments has been a challenging task because of the widespread presence of random false positives. Here, we present a network-based statistical algorithm that overcomes this difficulty and allows us to derive functions of unannotated proteins from large-scale interaction data. Our algorithm uses the insight that if two proteins share significantly larger number of common interaction partners than random, they have close functional associations. Analysis of publicly available data from Saccharomyces cerevisiae reveals >2,800 reliable functional associations, 29% of which involve at least one unannotated protein. By further analyzing these associations, we derive tentative functions for 81 unannotated proteins with high certainty. Our method is not overly sensitive to the false positives present in the data. Even after adding 50% randomly generated interactions to the measured data set, we are able to recover almost all (approximately 89%) of the original associations.

Controlling dispersion forces between small particles with artificially created random light fields

PubMed Central

Brügger, Georges; Froufe-Pérez, Luis S.; Scheffold, Frank; José Sáenz, Juan

2015-01-01

Appropriate combinations of laser beams can be used to trap and manipulate small particles with optical tweezers as well as to induce significant optical binding forces between particles. These interaction forces are usually strongly anisotropic depending on the interference landscape of the external fields. This is in contrast with the familiar isotropic, translationally invariant, van der Waals and, in general, Casimir–Lifshitz interactions between neutral bodies arising from random electromagnetic waves generated by equilibrium quantum and thermal fluctuations. Here we show, both theoretically and experimentally, that dispersion forces between small colloidal particles can also be induced and controlled using artificially created fluctuating light fields. Using optical tweezers as a gauge, we present experimental evidence for the predicted isotropic attractive interactions between dielectric microspheres induced by laser-generated, random light fields. These light-induced interactions open a path towards the control of translationally invariant interactions with tuneable strength and range in colloidal systems. PMID:26096622

Interaction effects among IFN-γ+874, IL-2-330, IL-10-1082, IL-10-592 and IL-4-589 polymorphisms on the clinical progression of subjects infected with hepatitis B virus and/or hepatitis C virus: a retrospective nested case–control study

PubMed Central

Gao, Qiu-Ju; Xie, Jia-Xin; Wang, Li-Min; Zhou, Qiang; Zhang, Shi-Yong

2017-01-01

Background The natural outcomes of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infections vary considerably among individuals The infection may heal naturally, or patients may succumb to chronic liver diseases, including chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. The mechanism is not fully understood. Objectives To evaluate the interaction among four single nucleotide polymorphisms (SNPs) and their influence on different clinical outcomes. Methods 277 individuals infected with HBV and/or HCV, including 81 patients with chronic hepatitis B and C, 122 asymptomatic HBV and/or HCV carriers and 74 controls who cleared HBV and HCV spontaneously, were involved in this study. The SNPs of four genes (rs2069762/−330 G/T of IL-2, rs2430561/+874A>T of IFN-γ, rs1800896/−1082G>A and rs1800872/−592C>A of IL-10 and rs2243250/−589C>T of IL-4) were analysed using restriction fragment length polymorphism-polymerase chain reaction or sequence-specific primer PCR. The gene–gene interactions were assessed using the multifactor-dimensionality reduction method. Results Interleukin (IL)-10-592 AC and IL-4-589 CC/CT showed a synergistic effect on liver inflammatory injury (p<0.01), whereas interferon (IFN)-γ+874  AA and IL-2-330 TT had a synergistic impact (p<0.05). IFN-γ+874  AA and IL-10-1082 AA had an antagonistic effect (p<0.01) on the clinical progression, including asymptomatic HBV and HCV carriers and chronic hepatitis. IL-2-330 TT and IL-10-1082 AA synergistically influenced the clinical outcome (p<0.05). IFN-γ+874 AA, IL-2-330 TT and IL-10-1082 AA interactively affected the clinical outcome including asymptomatic HBV and HCV carriers and chronic hepatitis (p<0.05). Conclusions Interactions among polymorphisms of IFN-γ+874 AA, IL-2-330 TT, IL-10-1082 AA, IL10-−592 AC and IL-4-589 CC/CT significantly influenced the clinical progression of the subjects with HBV and/or HCV infection. PMID:28838891

Interaction effects among IFN-γ+874, IL-2-330, IL-10-1082, IL-10-592 and IL-4-589 polymorphisms on the clinical progression of subjects infected with hepatitis B virus and/or hepatitis C virus: a retrospective nested case-control study.

PubMed

Gao, Qiu-Ju; Xie, Jia-Xin; Wang, Li-Min; Zhou, Qiang; Zhang, Shi-Yong

2017-08-23

The natural outcomes of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infections vary considerably among individuals The infection may heal naturally, or patients may succumb to chronic liver diseases, including chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. The mechanism is not fully understood. To evaluate the interaction among four single nucleotide polymorphisms (SNPs) and their influence on different clinical outcomes. 277 individuals infected with HBV and/or HCV, including 81 patients with chronic hepatitis B and C, 122 asymptomatic HBV and/or HCV carriers and 74 controls who cleared HBV and HCV spontaneously, were involved in this study. The SNPs of four genes ( rs2069762/-330 G/T of IL-2 , rs2430561/+874A>T of IFN-γ, rs1800896/-1082G>A  and rs1800872/-592C>A of IL-10 and rs2243250/ -589 C>T of IL-4 ) were analysed using restriction fragment length polymorphism-polymerase chain reaction or sequence-specific primer PCR. The gene-gene interactions were assessed using the multifactor-dimensionality reduction method. Interleukin (IL)-10-592 AC and IL-4-589 CC/CT showed a synergistic effect on liver inflammatory injury (p<0.01), whereas interferon (IFN)-γ+874  AA and IL-2-330 TT had a synergistic impact (p<0.05). IFN-γ+874  AA and IL-10-1082 AA had an antagonistic effect (p<0.01) on the clinical progression, including asymptomatic HBV and HCV carriers and chronic hepatitis. IL-2-330 TT and IL-10-1082 AA synergistically influenced the clinical outcome (p<0.05). IFN-γ+874 AA, IL-2-330 TT and IL-10-1082 AA interactively affected the clinical outcome including asymptomatic HBV and HCV carriers and chronic hepatitis (p<0.05). Interactions among polymorphisms of IFN-γ+874 AA, IL-2-330 TT, IL-10-1082 AA, IL10--592 AC and IL-4-589 CC/CT significantly influenced the clinical progression of the subjects with HBV and/or HCV infection. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Relationship and interaction between folate and expression of methyl-CpG-binding protein 2 in cervical cancerization].

PubMed

Li, Q L; Ding, L; Nan, J; Liu, C L; Yang, Z K; Chen, F; Liang, Y L; Wang, J T

2016-07-01

To explore the interaction between folate and the expression of methyl-CpG-binding protein 2(MeCP2)in cervical cancerization. Forty one patients diagnosed with cervical squamous cell carcinoma(SCC), 71 patients diagnosed with cervical intraepithelial neoplasm(CIN1, n=34; CIN2 +, n=37)and 61 women with normal cervix(NC)were recruited in this study. Microbiological assay was conducted to detect the levels of serum folate and RBC folate, Western blot assay and real-time PCR were performed to detect the expression levels of MeCP2 protein and mRNA, respectively. The data were analyzed by Kruskal-Wallis H test, χ(2) test, trend χ(2) test and Spearman correlation with SPSS statistical software(version 20.0), and the interaction were evaluated by using generalized multifactor dimensionality reduction(GMDR)model. The levels of serum folate(H=44.71, P<0.001; trend χ(2)=24.48, P<0.001)and RBC folate(H=5.28, P<0.001; trend χ(2)=3.83, P<0.05)decreased gradually along with the severity of cervical lesions. There was a positive correlation between serum folate level and RBC folate level(r=0.270, P< 0.001). The expression levels of MeCP2 protein(H=33.72, P<0.001; trend χ(2)=14.74, P<0.001)and mRNA(H=19.50, P<0.001; trend χ(2)=10.74, P<0.001)increased gradually along with the severity of cervical lesions. There were negative correlation between folate level and the expression level of MeCP2 protein(serum folate: r=-0.226, P=0.003; RBC folate: r=-0.164, P=0.004). Moreover, the results by GMDR model revealed there were interaction among serum folate deficiency, RBC folate deficiency, MeCP2 protein high expression and MeCP2 mRNA high expression in SCC and CIN2 + patients. Folate deficiency and high expression of MeCP2 gene might increase the risk of cervical cancer and its precancerous lesions through interaction among serum folate deficiency, RBC folate deficiency, MeCP2 protein high expression and mRNA high expression in the progression of cervical cancerization.

Unravelling changing interspecific interactions across environmental gradients using Markov random fields.

PubMed

Clark, Nicholas J; Wells, Konstans; Lindberg, Oscar

2018-05-16

Inferring interactions between co-occurring species is key to identify processes governing community assembly. Incorporating interspecific interactions in predictive models is common in ecology, yet most methods do not adequately account for indirect interactions (where an interaction between two species is masked by their shared interactions with a third) and assume interactions do not vary along environmental gradients. Markov random fields (MRF) overcome these limitations by estimating interspecific interactions, while controlling for indirect interactions, from multispecies occurrence data. We illustrate the utility of MRFs for ecologists interested in interspecific interactions, and demonstrate how covariates can be included (a set of models known as Conditional Random Fields, CRF) to infer how interactions vary along environmental gradients. We apply CRFs to two data sets of presence-absence data. The first illustrates how blood parasite (Haemoproteus, Plasmodium, and nematode microfilaria spp.) co-infection probabilities covary with relative abundance of their avian hosts. The second shows that co-occurrences between mosquito larvae and predatory insects vary along water temperature gradients. Other applications are discussed, including the potential to identify replacement or shifting impacts of highly connected species along climate or land-use gradients. We provide tools for building CRFs and plotting/interpreting results as an R package. © 2018 by the Ecological Society of America.

Embedded random matrix ensembles from nuclear structure and their recent applications

NASA Astrophysics Data System (ADS)

Kota, V. K. B.; Chavda, N. D.

Embedded random matrix ensembles generated by random interactions (of low body rank and usually two-body) in the presence of a one-body mean field, introduced in nuclear structure physics, are now established to be indispensable in describing statistical properties of a large number of isolated finite quantum many-particle systems. Lie algebra symmetries of the interactions, as identified from nuclear shell model and the interacting boson model, led to the introduction of a variety of embedded ensembles (EEs). These ensembles with a mean field and chaos generating two-body interaction generate in three different stages, delocalization of wave functions in the Fock space of the mean-field basis states. The last stage corresponds to what one may call thermalization and complex nuclei, as seen from many shell model calculations, lie in this region. Besides briefly describing them, their recent applications to nuclear structure are presented and they are (i) nuclear level densities with interactions; (ii) orbit occupancies; (iii) neutrinoless double beta decay nuclear transition matrix elements as transition strengths. In addition, their applications are also presented briefly that go beyond nuclear structure and they are (i) fidelity, decoherence, entanglement and thermalization in isolated finite quantum systems with interactions; (ii) quantum transport in disordered networks connected by many-body interactions with centrosymmetry; (iii) semicircle to Gaussian transition in eigenvalue densities with k-body random interactions and its relation to the Sachdev-Ye-Kitaev (SYK) model for majorana fermions.

Accounting for mudflow genesis in preliminary assessment of the maximum volume of solid mudflow sediments in the North Caucasus

NASA Astrophysics Data System (ADS)

Zalikhanov, M. Ch.; Kondratieva, N. V.; Adzhiev, A. Kh.; Razumov, V. V.

2016-09-01

The area of investigation was subject to multifactor analysis of the relationship between the maximum amount of mudflow solid sediments ( W) and parameters such as the mudflow basin area ( S), average channel slope (α), and mudflow channel length ( L). They were used to obtain analytical expressions in order to approximate the W( S, L, α) relation based on the mudflow genesis and source height. Statistical data on mudflow manifestations in different basins in the North Caucasus covering more than fifty years were used to obtain the analytical expressions in order to assess the maximum volume of mudflow solid sediments.

Prospect Theory and Interval-Valued Hesitant Set for Safety Evacuation Model

NASA Astrophysics Data System (ADS)

Kou, Meng; Lu, Na

2018-01-01

The study applies the research results of prospect theory and multi attribute decision making theory, combined with the complexity, uncertainty and multifactor influence of the underground mine fire system and takes the decision makers’ psychological behavior of emotion and intuition into full account to establish the intuitionistic fuzzy multiple attribute decision making method that is based on the prospect theory. The model established by this method can explain the decision maker’s safety evacuation decision behavior in the complex system of underground mine fire due to the uncertainty of the environment, imperfection of the information and human psychological behavior and other factors.

Financial model calibration using consistency hints.

PubMed

Abu-Mostafa, Y S

2001-01-01

We introduce a technique for forcing the calibration of a financial model to produce valid parameters. The technique is based on learning from hints. It converts simple curve fitting into genuine calibration, where broad conclusions can be inferred from parameter values. The technique augments the error function of curve fitting with consistency hint error functions based on the Kullback-Leibler distance. We introduce an efficient EM-type optimization algorithm tailored to this technique. We also introduce other consistency hints, and balance their weights using canonical errors. We calibrate the correlated multifactor Vasicek model of interest rates, and apply it successfully to Japanese Yen swaps market and US dollar yield market.

Leadership Styles of Oxford House Officers

PubMed Central

Komer, Anne C; Jason, Leonard A; Harvey, Ronald; Olson, Brad

2015-01-01

Oxford House recovery homes are unusual compared to most recovery homes in that they function entirely without the use of staff; instead members are elected to officer positions. The aim of this study was to perform preliminary analysis of the types of leadership styles utilized by members of oxford house. Twentynine house residents of five Oxford Houses were asked to rate their own leadership styles using the leader behavior description questionnaire and the multifactor leader questionnaire. Results showed that participants were more likely to use person-oriented behaviors above task-oriented actions. Transformational leadership was associated with higher outcomes than Transactional leadership. Implications for future research are discussed. PMID:26380329

Leadership Styles of Oxford House Officers.

PubMed

Komer, Anne C; Jason, Leonard A; Harvey, Ronald; Olson, Brad

Oxford House recovery homes are unusual compared to most recovery homes in that they function entirely without the use of staff; instead members are elected to officer positions. The aim of this study was to perform preliminary analysis of the types of leadership styles utilized by members of oxford house. Twentynine house residents of five Oxford Houses were asked to rate their own leadership styles using the leader behavior description questionnaire and the multifactor leader questionnaire. Results showed that participants were more likely to use person-oriented behaviors above task-oriented actions. Transformational leadership was associated with higher outcomes than Transactional leadership. Implications for future research are discussed.

Histologic effects of a high-repetition pulsed Nd:YAG laser on intraoral soft tissue

NASA Astrophysics Data System (ADS)

White, Joel M.; Goodis, Harold E.; Yessik, Michael J.; Myers, Terry D.

1995-05-01

High-repetition rate, fiberoptic-delivered Nd:YAG lasers have increased oral soft tissue laser applications. This study focused on three parameters: the temperature rise occurring in deeper tissue during excision, the histology of thermal coagulation during excision of oral tissue, and effects of accidental exposure to adjacent hard tissue. Thermocouples were placed 5.0 +/- 0.5 mm in bone below fresh bovine gingiva and at the same depth in tongue; temperatures in the underlying tissue were measured during laser excision. An Nd:YAG laser with 100 microsecond(s) pulse duration was used to excise the tissue using a 200 or 300 micrometers diameter fiber in contact with the tissue. The soft tissue was excised using constant force and rate with laser powers of 1.5, 3, 5, and 10 W, and a variety of pulse rates. The tissue was bioprepared, sectioned and stained with hematoxylin and eosin. The width and depth of the tissue removed as well as lateral and deep thermal coagulation were measured in histologic sections with a measuring microscope (10x). Multifactor randomized ANOVA showed that probe diameter and repetition rates were not significant variables (p

Non-equilibrium many-body dynamics following a quantum quench

NASA Astrophysics Data System (ADS)

Vyas, Manan

2017-12-01

We study analytically and numerically the non-equilibrium dynamics of an isolated interacting many-body quantum system following a random quench. We model the system Hamiltonian by Embedded Gaussian Orthogonal Ensemble (EGOE) of random matrices with one plus few-body interactions for fermions. EGOE are paradigmatic models to study the crossover from integrability to chaos in interacting many-body quantum systems. We obtain a generic formulation, based on spectral variances, for describing relaxation dynamics of survival probabilities as a function of rank of interactions. Our analytical results are in good agreement with numerics.

Dissecting partner recognition by an intrinsically disordered protein using descriptive random mutagenesis.

PubMed

Gruet, Antoine; Dosnon, Marion; Vassena, Andrea; Lombard, Vincent; Gerlier, Denis; Bignon, Christophe; Longhi, Sonia

2013-09-23

In view of getting insights into the molecular determinants of the binding efficiency of intrinsically disordered proteins (IDPs), we used random mutagenesis. As a proof of concept, we chose the interaction between the intrinsically disordered C-terminal domain of the measles virus nucleoprotein (NTAIL) and the X domain (XD) of the viral phosphoprotein and assessed how amino acid substitutions introduced at random within NTAIL affect partner recognition. In contrast with directed evolution approaches, we did not apply any selection and used the gene library approach not for production purposes but for achieving a better understanding of the NTAIL/XD interaction. For that reason, and to differentiate our approach from similar approaches that make use of systematic (i.e., targeted) mutagenesis, we propose to call it "descriptive random mutagenesis" (DRM). NTAIL variants generated by error-prone PCR were picked at random in the absence of selection pressure and were characterized in terms of sequence and binding abilities toward XD. DRM not only identified determinants of NTAIL/XD interaction that were in good agreement with previous work but also provided new insights. In particular, we discovered that the primary interaction site is poorly evolvable in terms of binding abilities toward XD. We also identified a critical NTAIL residue whose role in stabilizing the NTAIL/XD complex had previously escaped detection, and we identified NTAIL regulatory sites that dampen the interaction while being located outside the primary interaction site. Results show that DRM is a valuable approach to study binding abilities of IDPs. © 2013 Elsevier Ltd. All rights reserved.

Group Random Call Can Positively Affect Student In-Class Clicker Discussions

PubMed Central

Knight, Jennifer K.; Wise, Sarah B.; Sieke, Scott

2016-01-01

Understanding how instructional techniques and classroom norms influence in-class student interactions has the potential to positively impact student learning. Many previous studies have shown that students benefit from discussing their ideas with one another in class. In this study of introductory biology students, we explored how using an in-class accountability system might affect the nature of clicker-question discussions. Clicker-question discussions in which student groups were asked to report their ideas voluntarily (volunteer call) were compared with discussions in which student groups were randomly selected to report their ideas (random call). We hypothesized that the higher-accountability condition (random call) would impress upon students the importance of their discussions and thus positively influence how they interacted. Our results suggest that a higher proportion of discussions in the random call condition contained exchanges of reasoning, some forms of questioning, and both on- and off-topic comments compared with discussion in the volunteer call condition. Although group random call does not impact student performance on clicker questions, the positive impact of this instructional approach on exchanges of reasoning and other features suggests it may encourage some types of student interactions that support learning. PMID:27856544

Probabilistic material strength degradation model for Inconel 718 components subjected to high temperature, high-cycle and low-cycle mechanical fatigue, creep and thermal fatigue effects

NASA Technical Reports Server (NTRS)

Bast, Callie C.; Boyce, Lola

1995-01-01

This report presents the results of both the fifth and sixth year effort of a research program conducted for NASA-LeRC by The University of Texas at San Antonio (UTSA). The research included on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes five effects that typically reduce lifetime strength: high temperature, high-cycle mechanical fatigue, low-cycle mechanical fatigue, creep and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for five variables, namely, high temperature, high-cycle and low-cycle mechanical fatigue, creep and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using an updated version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of high-cycle mechanical fatigue, creep and thermal fatigue was performed. Then using the current version of PROMISS, entitled PROMISS94, a second sensitivity study including the effect of low-cycle mechanical fatigue, as well as, the three previous effects was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of high-cycle mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.

Many-body localization in Ising models with random long-range interactions

NASA Astrophysics Data System (ADS)

Li, Haoyuan; Wang, Jia; Liu, Xia-Ji; Hu, Hui

2016-12-01

We theoretically investigate the many-body localization phase transition in a one-dimensional Ising spin chain with random long-range spin-spin interactions, Vi j∝|i-j |-α , where the exponent of the interaction range α can be tuned from zero to infinitely large. By using exact diagonalization, we calculate the half-chain entanglement entropy and the energy spectral statistics and use them to characterize the phase transition towards the many-body localization phase at infinite temperature and at sufficiently large disorder strength. We perform finite-size scaling to extract the critical disorder strength and the critical exponent of the divergent localization length. With increasing α , the critical exponent experiences a sharp increase at about αc≃1.2 and then gradually decreases to a value found earlier in a disordered short-ranged interacting spin chain. For α <αc , we find that the system is mostly localized and the increase in the disorder strength may drive a transition between two many-body localized phases. In contrast, for α >αc , the transition is from a thermalized phase to the many-body localization phase. Our predictions could be experimentally tested with an ion-trap quantum emulator with programmable random long-range interactions, or with randomly distributed Rydberg atoms or polar molecules in lattices.

Modeling Local Interactions during the Motion of Cyanobacteria

PubMed Central

Galante, Amanda; Wisen, Susanne; Bhaya, Devaki; Levy, Doron

2012-01-01

Synechocystis sp., a common unicellular freshwater cyanobacterium, has been used as a model organism to study phototaxis, an ability to move in the direction of a light source. This microorganism displays a number of additional characteristics such as delayed motion, surface dependence, and a quasi-random motion, where cells move in a seemingly disordered fashion instead of in the direction of the light source, a global force on the system. These unexplained motions are thought to be modulated by local interactions between cells such as intercellular communication. In this paper, we consider only local interactions of these phototactic cells in order to mathematically model this quasi-random motion. We analyze an experimental data set to illustrate the presence of quasi-random motion and then derive a stochastic dynamic particle system modeling interacting phototactic cells. The simulations of our model are consistent with experimentally observed phototactic motion. PMID:22713858

Parent-Child Interaction Therapy with Physically Abusive Parents: Efficacy for Reducing Future Abuse Reports

ERIC Educational Resources Information Center

Chaffin, Mark; Silovsky, Jane F.; Funderburk, Beverly; Valle, Linda Anne; Brestan, Elizabeth V.; Balachova, Tatiana; Jackson, Shelli; Lensgraf, Jay; Bonner, Barbara L.

2004-01-01

A randomized trial was conducted to test the efficacy and sufficiency of parent-child interaction therapy (PCIT) in preventing re-reports of physical abuse among abusive parents. Physically abusive parents (N=110) were randomly assigned to one of three intervention conditions: (a) PCIT, (b) PCIT plus individualized enhanced services, or (c) a…

Random walk of passive tracers among randomly moving obstacles.

PubMed

Gori, Matteo; Donato, Irene; Floriani, Elena; Nardecchia, Ilaria; Pettini, Marco

2016-04-14

This study is mainly motivated by the need of understanding how the diffusion behavior of a biomolecule (or even of a larger object) is affected by other moving macromolecules, organelles, and so on, inside a living cell, whence the possibility of understanding whether or not a randomly walking biomolecule is also subject to a long-range force field driving it to its target. By means of the Continuous Time Random Walk (CTRW) technique the topic of random walk in random environment is here considered in the case of a passively diffusing particle among randomly moving and interacting obstacles. The relevant physical quantity which is worked out is the diffusion coefficient of the passive tracer which is computed as a function of the average inter-obstacles distance. The results reported here suggest that if a biomolecule, let us call it a test molecule, moves towards its target in the presence of other independently interacting molecules, its motion can be considerably slowed down.

Transformational leadership and the mental health team.

PubMed

Corrigan, Patrick W; Diwan, Sarah; Campion, John; Rashid, Fadwa

2002-11-01

Bass's (1990) multifactor model contrasts transformational and transactional styles of leadership with an essentially ineffective style: laissez-faire leadership. This study examines the relationship between these leadership styles and measures of organizational culture and staff burnout in mental health services teams. There were 236 leaders and 620 subordinates from 54 mental health teams who provided their perceptions of leadership style, organizational culture, and burnout in their program. Results show transformational leadership to be positively associated with a cohesive organizational culture and negatively associated with burnout. Moreover, leaders and subordinates differ in their ratings of transformational leadership-leaders viewed themselves more positively. These findings are helpful for understanding the central role of leaders in the organizational structure of teams.

[Suicidality and musical preferences: a possible link?].

PubMed

Mikolajczak, Gladys; Desseilles, Martin

2012-01-01

Music is an important part of young people's lives. In this article, we attempt to answer two questions on the links between music et suicide. First, we examine if certain types of music favor suicidal process (ideation and acting out); and, secondly, we examine if music can constitute a tool to reduce the risk of suicide. Several factors possibly involved in links between musical preferences and the suicidal process are developed: the Velten effect and the musical mood induction procedure, the identification and the learning by imitation, the media influence as well as the individual characteristics. A multifactor approach is necessary to understand the complex and birectional links that unite musical preferences and suicide risk.

[Genetic diseases in pediatric patients hospitalised in the town of Ubaté, Colombia].

PubMed

Páez, Paola; Suárez-Obando, Fernando; Zarante, Ignacio

2008-01-01

Describing genetic disease frequency in a second-level hospital's in-patient paediatric service The hospital's statistical department's records for 2005 were comprehensively reviewed; the study was carried out in the town of Ubaté during 2006. Complex diseases led to nearly 25% of all hospitalisations, including multifactor diseases and congenital malformations. However, an aetiological study and/or geneticist consultation or referral took place on a few occasions. Primary care hospitals should become more relevant reference centres for detecting genetic diseases amongst the paediatric population. New mechanisms are needed for implementing this to allow patients access to a geneticist and for an aetiological diagnosis to be made and providing suitable genetic counselling.

A computer software system for integration and analysis of grid-based remote sensing data with other natural resource data. Remote Sensing Project

NASA Technical Reports Server (NTRS)

Tilmann, S. E.; Enslin, W. R.; Hill-Rowley, R.

1977-01-01

A computer-based information system is described designed to assist in the integration of commonly available spatial data for regional planning and resource analysis. The Resource Analysis Program (RAP) provides a variety of analytical and mapping phases for single factor or multi-factor analyses. The unique analytical and graphic capabilities of RAP are demonstrated with a study conducted in Windsor Township, Eaton County, Michigan. Soil, land cover/use, topographic and geological maps were used as a data base to develope an eleven map portfolio. The major themes of the portfolio are land cover/use, non-point water pollution, waste disposal, and ground water recharge.

How Messenger RNA and Nascent Chain Sequences Regulate Translation Elongation.

PubMed

Choi, Junhong; Grosely, Rosslyn; Prabhakar, Arjun; Lapointe, Christopher P; Wang, Jinfan; Puglisi, Joseph D

2018-06-20

Translation elongation is a highly coordinated, multistep, multifactor process that ensures accurate and efficient addition of amino acids to a growing nascent-peptide chain encoded in the sequence of translated messenger RNA (mRNA). Although translation elongation is heavily regulated by external factors, there is clear evidence that mRNA and nascent-peptide sequences control elongation dynamics, determining both the sequence and structure of synthesized proteins. Advances in methods have driven experiments that revealed the basic mechanisms of elongation as well as the mechanisms of regulation by mRNA and nascent-peptide sequences. In this review, we highlight how mRNA and nascent-peptide elements manipulate the translation machinery to alter the dynamics and pathway of elongation.

Anxiety Levels Are Independently Associated With Cognitive Performance in an Australian Multiple Sclerosis Patient Cohort.

PubMed

Ribbons, Karen; Lea, Rodney; Schofield, Peter W; Lechner-Scott, Jeannette

2017-01-01

Neurological and psychological symptoms in multiple sclerosis can affect cognitive function. The objective of this study was to explore the relationship between psychological measures and cognitive performance in a patient cohort. In 322 multiple sclerosis patients, psychological symptoms were measured using the Depression Anxiety and Stress Scale, and cognitive function was evaluated using Audio Recorded Cognitive Screen. Multifactor linear regression analysis, accounting for all clinical covariates, found that anxiety was the only psychological measure to remain a significant predictor of cognitive performance (p<0.001), particularly memory function (p<0.001). Further prospective studies are required to determine whether treatment of anxiety improves cognitive impairment.

Non-linear continuous time random walk models★

NASA Astrophysics Data System (ADS)

Stage, Helena; Fedotov, Sergei

2017-11-01

A standard assumption of continuous time random walk (CTRW) processes is that there are no interactions between the random walkers, such that we obtain the celebrated linear fractional equation either for the probability density function of the walker at a certain position and time, or the mean number of walkers. The question arises how one can extend this equation to the non-linear case, where the random walkers interact. The aim of this work is to take into account this interaction under a mean-field approximation where the statistical properties of the random walker depend on the mean number of walkers. The implementation of these non-linear effects within the CTRW integral equations or fractional equations poses difficulties, leading to the alternative methodology we present in this work. We are concerned with non-linear effects which may either inhibit anomalous effects or induce them where they otherwise would not arise. Inhibition of these effects corresponds to a decrease in the waiting times of the random walkers, be this due to overcrowding, competition between walkers or an inherent carrying capacity of the system. Conversely, induced anomalous effects present longer waiting times and are consistent with symbiotic, collaborative or social walkers, or indirect pinpointing of favourable regions by their attractiveness. Contribution to the Topical Issue "Continuous Time Random Walk Still Trendy: Fifty-year History, Current State and Outlook", edited by Ryszard Kutner and Jaume Masoliver.

Interaction of TLR-IFN and HLA polymorphisms on susceptibility of chronic HBV infection in Southwest Han Chinese.

PubMed

He, Dengming; Tao, Shiqi; Guo, Shimin; Li, Maoshi; Wu, Junqiu; Huang, Hongfei; Guo, Xinwu; Yan, Guohua; Zhu, Peng; Wang, Yuming

2015-08-01

The toll-like receptor-interferon (TLR-IFN) signalling pathway plays a crucial role in HBV infection. Human leucocyte antigen (HLA) polymorphisms are associated with chronic HBV infection by genome wide association study (GWAS). We aimed to explore interaction between TLR-IFN and HLA gene polymorphisms in susceptibility of chronic HBV infection. In the Chinese Southwest Han population, 1191 chronic HBV infection patients and 273 HBV clearance were selected. A total of 39 single nucleotide polymorphism loci in 23 genes of the TLR-IFN pathway and four HLA polymorphism loci associated with chronic HBV infection identified by GWAS were selected for genotyping. SNPStats, QVALUE, and multifactor dimensionality reduction were used for statistical analysis. A significant association was seen in several of the TLR-IFN pathway genes, TLR9 rs352140 (OR = 0.70, P = 0.0088), IL1B rs16944 (OR = 0.67, P = 0.016), IL12B rs3212227 (OR = 1.38, P = 0.021), IFNGR1 rs3799488 (OR = 1.48, P = 0.0048), IFNGR2 rs1059293 (OR = 0.27, P = 0.011), MX1 rs467960 (OR = 0.68, P = 0.022), as well as four loci in HLA, rs3077 (OR = 0.55, P < 0.0001), rs2856718 (OR = 0.60, P = 4e-04), rs9277535 (OR = 0.54, P < 0.0001) and rs7453920 (OR = 0.43, P < 0.0001). A synergistic relationship was seen between rs9277535 and rs16944 (0.13%), rs1143623 and rs6613 (0.10%). The combination of rs9277535 in HLA and rs16944 in IL1B was the best model to predict chronic HBV infection (testing accuracy = 0.6040, P = 0.0010, cross-validation consistency = 10/10). TLR-IFN pathway gene polymorphisms are associated with chronic HBV infection. Interactions with polymorphisms in these genes may be one mechanism by which HLA polymorphisms influence susceptibility to chronic HBV infection, as specific single nucleotide polymorphism combinations are highly predictive of chronic HBV infection. © 2014 The Authors. Liver International Published by John Wiley & Sons Ltd.

Age- and gender-specific epistasis between ADA and TNF-α influences human life-expectancy.

PubMed

Napolioni, Valerio; Carpi, Francesco M; Giannì, Paola; Sacco, Roberto; Di Blasio, Luca; Mignini, Fiorenzo; Lucarini, Nazzareno; Persico, Antonio M

2011-11-01

Aging is a complex phenotype with multiple determinants but a strong genetic component significantly impacts on survival to extreme ages. The dysregulation of immune responses occurring with increasing age is believed to contribute to human morbidity and mortality. Conversely, some genetic determinants of successful aging might reside in those polymorphisms for the immune system genes regulating immune responses. Here we examined the main effects of single loci and multi-locus interactions to test the hypothesis that the adenosine deaminase (ADA) and tumor necrosis factor alpha (TNF-α) genes may influence human life-expectancy. ADA (22G>A, rs73598374) and TNF-α (-308G>A, rs1800629; -238G>A, rs361525) functional SNPs have been determined for 1071 unrelated healthy individuals from Central Italy (18-106 years old) divided into three gender-specific age classes defined according to demographic information and accounting for the different survivals between sexes: for men (women), the first class consists of individuals<66 years old (<73 years old), the second class of individuals 66-88 years old (73-91 years old), and the third class of individuals>88 years old (>91 years old). Single-locus analysis showed that only ADA 22G>A is significantly associated with human life-expectancy in males (comparison 1 (age class 2 vs. age class 1), O.R. 1.943, P=0.036; comparison 2 (age class 3 vs. age class 2), O.R. 0.320, P=0.0056). Age- and gender-specific patterns of epistasis between ADA and TNF-α were found using Generalized Multifactor Dimensionality Reduction (GMDR). In comparison 1, a significant two-loci interaction occurs in females between ADA 22G>A and TNF-α -238G>A (Sign Test P=0.011). In comparison 2, both two-loci and three-loci interaction are significant associated with increased life-expectancy over 88 years in males. In conclusion, we report that a combination of functional SNPs within ADA and TNF-α genes can influence life-expectancy in a gender-specific manner and that males and females follow different pathways to attain longevity. Copyright © 2011 Elsevier Ltd. All rights reserved.

Synergistic effects of gene polymorphisms of the renin-angiotensin-aldosterone system on essential hypertension in Kazakhs in Xinjiang.

PubMed

Niu, Shudong; Zhang, Bin; Zhang, Keyong; Zhu, Pengcheng; Li, Jingping; Sun, Yujing; He, Ning; Zhang, Mingtao; Gao, Zhiying; Li, Xueyan; Simayi, Amuti; Ge, Jie; Cong, Mingyu; Zhou, Wenna; Qiu, Changchun

2016-01-01

To assess the synergistic effects of gene polymorphisms of the renin-angiotensin-aldosterone system (RAAS) on essential hypertension (EH) in Kazakhs in Xinjiang. A cross-sectional case-control association study was conducted in 52 1 hypertensive and 623 normotensive subjects of Kazakh ethnicity on eight common single nucleotide polymorphisms (SNPs) interspersed over five genes of the RAAS. SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism. Interactions among the SNPs were analyzed by the multifactor dimensionality reduction method (MDR). In single-locus analysis, subjects with AGT -6G, ACE D, and CYP11B2 -344C had increased susceptibility to EH (OR: 1.249; 1.425; 1.201). When subgrouped by sex, males with the t allele of REN Taq I had decreased risk for EH (OR: 0.529), and those with AGT -6G and CYP11B2 -344 C had increased risk for EH (OR: 1.498; 1.449). In females, carrying ACE D increased the risk for EH. (OR: 1.327). In six AGT haplotypes, H1 was protective, while H3 increased susceptibility to EH (OR: 0.683; 2.025). Interaction analysis by MDR showed that there was a strong synergistic effect between ACE I/D and CY11B2 (T-344C) and a moderate interaction between both ACE I/D and CY11B2 T-344C and AGT A-6G. There was a strong synergistic effect between ACE I/D and CY11B2 T-344C and a moderate effect between both ACE I/D and CY11B2 T-344C and AGT A-6G. AGT -6G, ACE D, and CY11B2 -344C increased susceptibility to EH. REN Taq I, AGT -6G, CY11B2 -344 C and ACE D were associated with male and female EH, respectively. H1 and H3 of AGT were protective and risk haplotypes, respectively.

Screening toll-like receptor markers to predict latent tuberculosis infection and subsequent tuberculosis disease in a Chinese population.

PubMed

Wu, Linlin; Hu, Yi; Li, Dange; Jiang, Weili; Xu, Biao

2015-04-01

We investigated whether polymorphisms in the toll-like receptor genes or gene-gene interactions are associated with susceptibility to latent tuberculosis infection (LTBI) or subsequent pulmonary tuberculosis (PTB) in a Chinese population. Two matched case-control studies were undertaken. Previously reported polymorphisms in the toll-like receptors (TLRs) were compared between 422 healthy controls (HC) and 205 LTBI patients and between 205 LTBI patients and 109 PTB patients, to assess whether these polymorphisms and their interactions are associated with LTBI or PTB. A PCR-based restriction fragment length polymorphism analysis was used to detect genetic polymorphisms in the TLR genes. Nonparametric multifactor dimensionality reduction (MDR) was used to analyze the effects of interactions between complex disease genes and other genes or environmental factors. Sixteen markers in TLR1, TLR2, TLR4, TLR6, TLR8, TLR9, and TIRAP were detected. In TLR2, the frequencies of the CC genotype (OR = 2.262; 95% CI: 1.433-3.570) and C allele (OR = 1.566; 95% CI: 1.223-1.900) in single-nucleotide polymorphism (SNP) rs3804100 were significantly higher in the LTBI group than in the HC group, whereas the GA genotype of SNP rs5743708 was associated with PTB (OR = 6.087; 95% CI: 1.687-21.968). The frequencies of the GG genotype of SNP rs7873784 in TLR4 (OR = 2.136; 95% CI: 1.312-3.478) and the CC genotype of rs3764879 in TLR8 (OR = 1.982; 95% CI: 1.292-3.042) were also significantly higher in the PTB group than in the HC group. The TC genotype frequency of SNP rs5743836 in TLR9 was significantly higher in the LTBI group than in the HC group (OR = 1.664; 95% CI: 1.201-2.306). An MDR analysis of gene-gene and gene-environment interactions identified three SNPs (rs10759932, rs7873784, and rs10759931) that predicted LTBI with 84% accuracy (p = 0.0004) and three SNPs (rs3804100, rs1898830, and rs10759931) that predicted PTB with 80% accuracy (p = 0.0001). Our results suggest that genetic variation in TLR2, 4, 8 and 9, implicating TLR-related pathways affecting the innate immunity response, modulate LTBI and PTB susceptibility in Chinese.

Frequency of RNA–RNA interaction in a model of the RNA World

PubMed Central

STRIGGLES, JOHN C.; MARTIN, MATTHEW B.; SCHMIDT, FRANCIS J.

2006-01-01

The RNA World model for prebiotic evolution posits the selection of catalytic/template RNAs from random populations. The mechanisms by which these random populations could be generated de novo are unclear. Non-enzymatic and RNA-catalyzed nucleic acid polymerizations are poorly processive, which means that the resulting short-chain RNA population could contain only limited diversity. Nonreciprocal recombination of smaller RNAs provides an alternative mechanism for the assembly of larger species with concomitantly greater structural diversity; however, the frequency of any specific recombination event in a random RNA population is limited by the low probability of an encounter between any two given molecules. This low probability could be overcome if the molecules capable of productive recombination were redundant, with many nonhomologous but functionally equivalent RNAs being present in a random population. Here we report fluctuation experiments to estimate the redundancy of the set of RNAs in a population of random sequences that are capable of non-Watson-Crick interaction with another RNA. Parallel SELEX experiments showed that at least one in 106 random 20-mers binds to the P5.1 stem–loop of Bacillus subtilis RNase P RNA with affinities equal to that of its naturally occurring partner. This high frequency predicts that a single RNA in an RNA World would encounter multiple interacting RNAs within its lifetime, supporting recombination as a plausible mechanism for prebiotic RNA evolution. The large number of equivalent species implies that the selection of any single interacting species in the RNA World would be a contingent event, i.e., one resulting from historical accident. PMID:16495233

Association of the ACE, GSTM1, IL-6, NOS3, and CYP1A1 polymorphisms with susceptibility of mycoplasma pneumoniae pneumonia in Chinese children

PubMed Central

Zhao, Jie; Zhang, Wen; Shen, Li; Yang, Xiaomeng; Liu, Yi; Gai, Zhongtao

2017-01-01

Abstract Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) and the clinical presentation of mycoplasma pneumoniae pneumonia (MPP) varies widely. Genetic variability affecting the host response may also influence the susceptibility to MPP. Several studies have investigated the association between single nucleotide polymorphism (SNP) of some genes and the risks of CAP; however, the results were inconsistent. Here, we investigated the association of 5 functional genes and the risks of MPP, including ACE (rs4340), GSTM1 (Ins/del), IL-6 (rs1800795), NOS3 (rs1799983), and CYP1A1 (rs2606345) in a total of 715 subjects (415 cases, 300 controls) by using tetra-primer allele-specific polymerase chain reaction (PCR) and Sanger sequencing. The gene–gene interactions were analyzed using the Multifactor Dimensionality Reduction and cumulative genetic risk score approaches. Our results showed that 3 SNPs of ACE rs4340, IL-6 rs1800795, and NOS3 rs1799983 were significantly associated with the risks of MPP, while no differences were observed in genotype frequencies of GSTM1 (Ins/del) and CYP1A1 rs2606345 between both groups. The combinations of ACE rs4340D/NOS3 rs1799983T/CYP1A1 rs2606345G and ACE rs4340D/NOS3 rs1799983T contribute to the genetic susceptibility of MPP in Chinese children. PMID:28403117

Multilocus analysis reveals three candidate genes for Chinese migraine susceptibility.

PubMed

An, X-K; Fang, J; Yu, Z-Z; Lin, Q; Lu, C-X; Qu, H-L; Ma, Q-L

2017-08-01

Several genome-wide association studies (GWASs) in Caucasian populations have identified 12 loci that are significantly associated with migraine. More evidence suggests that serotonin receptors are also involved in migraine pathophysiology. In the present study, a case-control study was conducted in a cohort of 581 migraine cases and 533 ethnically matched controls among a Chinese population. Eighteen polymorphisms from serotonin receptors and GWASs were selected, and genotyping was performed using a Sequenom MALDI-TOF mass spectrometry iPLEX platform. The genotypic and allelic distributions of MEF2D rs2274316 and ASTN2 rs6478241 were significantly different between migraine patients and controls. Univariate and multivariate analysis revealed significant associations of polymorphisms in the MEF2D and ASTN2 genes with migraine susceptibility. MEF2D, PRDM16 and ASTN2 were also found to be associated with migraine without aura (MO) and migraine with family history. And, MEF2D and ASTN2 also served as genetic risk factors for the migraine without family history. The generalized multifactor dimensionality reduction analysis identified that MEF2D and HTR2E constituted the two-factor interaction model. Our study suggests that the MEF2D, PRDM16 and ASTN2 genes from GWAS are associated with migraine susceptibility, especially MO, among Chinese patients. It appears that there is no association with serotonin receptor related genes. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Interaction between juniper Juniperus communis L. and its fruit pest insects: Pest abundance, fruit characteristics and seed viability

NASA Astrophysics Data System (ADS)

García, Daniel

1998-12-01

The relationships between the fruit features of Juniperus communis and the presence of fruit pests were studied in Sierra Nevada, SE Spain. The abundance of two insect species — a pulp-sucking scale and a seed-predator wasp — was surveyed with respect both to fruit characteristics and to viability of seeds contained therein. Seed-predator pressure was not significantly related to any fruit characteristics; however, pulp suckers tended to be more abundant in plants with low pulp: seed ratios and high fruit-water content. In addition, fruits with high levels of pulp-sucker attack tended to have higher water content. A multi-factor ANOVA, considering the identity of the plant and the attack of the different pests as factors, showed that plant identity accounts for most of the variation in fruit characteristics. The viability of seeds tended to be lower in plants strongly attacked by both pests. Fruits attacked by seed predators showed significantly lower proportions of viable and unviable seeds than did unattacked fruits. Seed viability was also lower in those fruits heavily attacked by pulp suckers, but this pattern is strongly mediated by plant identity. Pest activity proved to be clearly associated with a direct decrease in juniper reproductive capacity. This loss involved a reduction of the viable-seed number, mainly related to the seed predator, as well as a reduction of fruit attractiveness to frugivorous dispersers, related to the pulp sucker.

In vitro growth of Curcuma longa L. in response to five mineral elements and plant density in fed-batch culture systems.

PubMed

El-Hawaz, Rabia F; Bridges, William C; Adelberg, Jeffrey W

2015-01-01

Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments' macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes.

In Vitro Growth of Curcuma longa L. in Response to Five Mineral Elements and Plant Density in Fed-Batch Culture Systems

PubMed Central

El-Hawaz, Rabia F.; Bridges, William C.; Adelberg, Jeffrey W.

2015-01-01

Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments’ macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes. PMID:25830292

Analysis of random structure-acoustic interaction problems using coupled boundary element and finite element methods

NASA Technical Reports Server (NTRS)

Mei, Chuh; Pates, Carl S., III

1994-01-01

A coupled boundary element (BEM)-finite element (FEM) approach is presented to accurately model structure-acoustic interaction systems. The boundary element method is first applied to interior, two and three-dimensional acoustic domains with complex geometry configurations. Boundary element results are very accurate when compared with limited exact solutions. Structure-interaction problems are then analyzed with the coupled FEM-BEM method, where the finite element method models the structure and the boundary element method models the interior acoustic domain. The coupled analysis is compared with exact and experimental results for a simplistic model. Composite panels are analyzed and compared with isotropic results. The coupled method is then extended for random excitation. Random excitation results are compared with uncoupled results for isotropic and composite panels.

Many-body delocalization with random vector potentials

NASA Astrophysics Data System (ADS)

Cheng, Chen; Mondaini, Rubem

2016-11-01

We study the ergodic properties of excited states in a model of interacting fermions in quasi-one-dimensional chains subjected to a random vector potential. In the noninteracting limit, we show that arbitrarily small values of this complex off-diagonal disorder trigger localization for the whole spectrum; the divergence of the localization length in the single-particle basis is characterized by a critical exponent ν which depends on the energy density being investigated. When short-range interactions are included, the localization is lost, and the system is ergodic regardless of the magnitude of disorder in finite chains. Our numerical results suggest a delocalization scheme for arbitrary small values of interactions. This finding indicates that the standard scenario of the many-body localization cannot be obtained in a model with random gauge fields.

Stochastic interactions of two Brownian hard spheres in the presence of depletants

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

Karzar-Jeddi, Mehdi; Fan, Tai-Hsi, E-mail: thfan@engr.uconn.edu; Tuinier, Remco

2014-06-07

A quantitative analysis is presented for the stochastic interactions of a pair of Brownian hard spheres in non-adsorbing polymer solutions. The hard spheres are hypothetically trapped by optical tweezers and allowed for random motion near the trapped positions. The investigation focuses on the long-time correlated Brownian motion. The mobility tensor altered by the polymer depletion effect is computed by the boundary integral method, and the corresponding random displacement is determined by the fluctuation-dissipation theorem. From our computations it follows that the presence of depletion layers around the hard spheres has a significant effect on the hydrodynamic interactions and particle dynamicsmore » as compared to pure solvent and uniform polymer solution cases. The probability distribution functions of random walks of the two interacting hard spheres that are trapped clearly shift due to the polymer depletion effect. The results show that the reduction of the viscosity in the depletion layers around the spheres and the entropic force due to the overlapping of depletion zones have a significant influence on the correlated Brownian interactions.« less

[Gene-gene interaction on central obesity in school-aged children in China].

PubMed

Fu, L W; Zhang, M X; Wu, L J; Gao, L W; Mi, J

2017-07-10

Objective: To investigate possible effect of 6 obesity-associated SNPs in contribution to central obesity and examine whether there is an interaction in the 6 SNPs in the cause of central obesity in school-aged children in China. Methods: A total of 3 502 school-aged children who were included in Beijing Child and Adolescent Metabolic Syndrome (BCAMS) Study were selected, and based on the age and sex specific waist circumference (WC) standards in the BCAMS study, 1 196 central obese cases and 2 306 controls were identified. Genomic DNA was extracted from peripheral blood white cells using the salt fractionation method. A total of 6 single nucleotide polymorphisms ( FTO rs9939609, MC4R rs17782313, BDNF rs6265, PCSK1 rs6235, SH2B1 rs4788102, and CSK rs1378942) were genotyped by TaqMan allelic discrimination assays with the GeneAmp 7900 sequence detection system (Applied Biosystems, Foster City, CA, USA). Logistic regression model was used to investigate the association between 6 SNPs and central obesity. Gene-gene interactions among 6 polymorphic loci were analyzed by using the Generalized Multifactor Dimensionality Reduction (GMDR) method, and then logistic regression model was constructed to confirm the best combination of loci identified in the GMDR. Results: After adjusting gender, age, Tanner stage, physical activity and family history of obesity, the FTO rs9939609-A, MC4R rs17782313-C and BDNF rs6265-G alleles were associated with central obesity under additive genetic model ( OR =1.24, 95 %CI : 1.06-1.45, P =0.008; OR =1.26, 95 %CI : 1.11-1.43, P =2.98×10(-4); OR =1.18, 95 % CI : 1.06-1.32, P =0.003). GMDR analysis showed a significant gene-gene interaction between MC4R rs17782313 and BDNF rs6265 ( P =0.001). The best two-locus combination showed the cross-validation consistency of 10/10 and testing accuracy of 0.539. This interaction showed the maximum consistency and minimum prediction error among all gene-gene interaction models evaluated. Moreover, the combination of MC4R rs17782313-C and BDNF rs6265-G was associated with an increased risk of central obesity after adjustment for gender, age, Tanner stage, physical activity and family history of obesity. Conclusions: Our study showed that FTO rs9939609-A, MC4R rs17782313-C and BDNF rs6265-G alleles were associated with central obesity, and statistical interaction between MC4R rs17782313-C and BDNF rs6265-G increased risk of central obesity in school-aged children in China.

Random density matrices versus random evolution of open system

NASA Astrophysics Data System (ADS)

Pineda, Carlos; Seligman, Thomas H.

2015-10-01

We present and compare two families of ensembles of random density matrices. The first, static ensemble, is obtained foliating an unbiased ensemble of density matrices. As criterion we use fixed purity as the simplest example of a useful convex function. The second, dynamic ensemble, is inspired in random matrix models for decoherence where one evolves a separable pure state with a random Hamiltonian until a given value of purity in the central system is achieved. Several families of Hamiltonians, adequate for different physical situations, are studied. We focus on a two qubit central system, and obtain exact expressions for the static case. The ensemble displays a peak around Werner-like states, modulated by nodes on the degeneracies of the density matrices. For moderate and strong interactions good agreement between the static and the dynamic ensembles is found. Even in a model where one qubit does not interact with the environment excellent agreement is found, but only if there is maximal entanglement with the interacting one. The discussion is started recalling similar considerations for scattering theory. At the end, we comment on the reach of the results for other convex functions of the density matrix, and exemplify the situation with the von Neumann entropy.

Winner of the society for biomaterials student award in the Ph.D. category for the annual meeting of the society for biomaterials, april 11-14, 2018, Atlanta, GA: Development of a bimodal, in situ crosslinking method to achieve multifactor release from electrospun gelatin.

PubMed

Kishan, Alysha; Walker, Taneidra; Sears, Nick; Wilems, Thomas; Cosgriff-Hernandez, Elizabeth

2018-05-01

To better mimic native tissue microenvironments, current efforts have moved beyond single growth factor delivery to more complex multiple growth factor delivery with distinct release profiles. Electrospun gelatin, a widely investigated drug delivery vehicle, requires postprocessing crosslinking techniques that generate a mesh with uniform crosslinking density, limiting the ability to deliver multiple factors at different rates. Herein, we describe a method to independently control release of multiple factors from a single electrospun gelatin mesh. Two in situ crosslinking modalities, photocrosslinking of methacyrlated gelatin and reactive crosslinking of gelatin with a diisocyanate, are coelectrospun to generate distinct fiber populations with different crosslinking chemistry and density in a single mesh. The photocrosslinked gelatin-methacrylate resulted in a relatively rapid release of a model protein (48 ± 12% at day 1, 96 ± 3% at day 10) due to diffusion of embedded protein from the crosslinked fibers. The reactive crosslinking system displayed a more sustained release (7 ± 5% at day 1, 33 ± 2% at day 10) that was attributed to the conjugation of protein to gelatin with the diisocyanate, requiring degradation of gelatin prior to diffusion out of the fibers. Both modalities displayed tunable release profiles. Subsequent release studies of a cospun mesh with two different crosslinked fiber populations confirmed that the cospun mesh displayed multifactor release with independent release profiles. Overall, this bimodal, in situ crosslinking approach enables the delivery of multiple factors with distinct release kinetics from a single mesh and is expected to have broad utility in tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1155-1164, 2018. © 2018 Wiley Periodicals, Inc.

Endotoxin exposure and changes in short-term pulmonary function among sewage workers.

PubMed

Cyprowski, Marcin; Sobala, Wojciech; Buczyńska, Alina; Szadkowska-Stańczyk, Irena

2015-01-01

The inhaled endotoxin is considered as a causative factor in the process of acute bronchial obstruction, which can be measured by a decrease in forced expiratory volume in 1 s (FEV1). The aim of this study was to assess endotoxin exposure among sewage treatment plant workers (STPW) and its effect on across-shift changes in respiratory airflow. A group of 78 STPW from a large sewage treatment plant was studied. Inhalable dust for endotoxin assessment was collected using personal aerosol samplers. Endotoxin was assayed with the kinetic, chromogenic Limulus amebocyte lysate test. Across-shift spirometric measurements were performed on Mondays, after 2-days absence from work, with the use of portable spirometer. The forced vital capacity (FVC), and FEV1 parameters were analyzed. Multifactor regression modeling was performed to determine parameters significantly associated with endotoxin exposure. The concentration of inhalable dust and endotoxin ranged from 0.01-1.38 mg/m3 and 0.68-214 endotoxin units per cubic meter of air (EU/m3), respectively. Endotoxins were characterized with the skewed distribution (arithmetic mean (AM) = 38.8 EU/m3, geometric mean (GM) = 15.4 EU/m3, geometric standard deviation (GSD) = 4.21). Through the use of multifactor analysis, which excluded the main confounders (inhalable dust and smoking habit) it was found that, despite low levels of endotoxin, it had significant impact on the observed across-shift decline in FEV1 (p = 0.044). For this parameter, the regression slope was additionally calculated (r = -0.017, p = 0.071). Relatively low levels of endotoxin among sewage treatment plant workers may cause small, but significant across-shift declines in FEV1. The observed relationship was independent of organic dust concentrations and smoking habit. The respiratory protection should be provided for STPW. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Random Measurement Error Does Not Bias the Treatment Effect Estimate in the Regression-Discontinuity Design. II. When an Interaction Effect Is Present.

ERIC Educational Resources Information Center

Trochim, William M. K.; And Others

1991-01-01

The regression-discontinuity design involving a treatment interaction effect (TIE), pretest-posttest functional form specification, and choice of point-of-estimation of the TIE are examined. Formulas for controlling the magnitude of TIE in simulations can be used for simulating the randomized experimental case where estimation is not at the…

How do we think machines think? An fMRI study of alleged competition with an artificial intelligence

PubMed Central

Chaminade, Thierry; Rosset, Delphine; Da Fonseca, David; Nazarian, Bruno; Lutcher, Ewald; Cheng, Gordon; Deruelle, Christine

2012-01-01

Mentalizing is defined as the inference of mental states of fellow humans, and is a particularly important skill for social interactions. Here we assessed whether activity in brain areas involved in mentalizing is specific to the processing of mental states or can be generalized to the inference of non-mental states by comparing brain responses during the interaction with an intentional and an artificial agent. Participants were scanned using fMRI during interactive rock-paper-scissors games while believing their opponent was a fellow human (Intentional agent, Int), a humanoid robot endowed with an artificial intelligence (Artificial agent, Art), or a computer playing randomly (Random agent, Rnd). Participants' subjective reports indicated that they adopted different stances against the three agents. The contrast of brain activity during interaction with the artificial and the random agents didn't yield any cluster at the threshold used, suggesting the absence of a reproducible stance when interacting with an artificial intelligence. We probed response to the artificial agent in regions of interest corresponding to clusters found in the contrast between the intentional and the random agents. In the precuneus involved in working memory, the posterior intraparietal suclus, in the control of attention and the dorsolateral prefrontal cortex, in executive functions, brain activity for Art was larger than for Rnd but lower than for Int, supporting the intrinsically engaging nature of social interactions. A similar pattern in the left premotor cortex and anterior intraparietal sulcus involved in motor resonance suggested that participants simulated human, and to a lesser extend humanoid robot actions, when playing the game. Finally, mentalizing regions, the medial prefrontal cortex and right temporoparietal junction, responded to the human only, supporting the specificity of mentalizing areas for interactions with intentional agents. PMID:22586381

How do we think machines think? An fMRI study of alleged competition with an artificial intelligence.

PubMed

Chaminade, Thierry; Rosset, Delphine; Da Fonseca, David; Nazarian, Bruno; Lutcher, Ewald; Cheng, Gordon; Deruelle, Christine

2012-01-01

Mentalizing is defined as the inference of mental states of fellow humans, and is a particularly important skill for social interactions. Here we assessed whether activity in brain areas involved in mentalizing is specific to the processing of mental states or can be generalized to the inference of non-mental states by comparing brain responses during the interaction with an intentional and an artificial agent. Participants were scanned using fMRI during interactive rock-paper-scissors games while believing their opponent was a fellow human (Intentional agent, Int), a humanoid robot endowed with an artificial intelligence (Artificial agent, Art), or a computer playing randomly (Random agent, Rnd). Participants' subjective reports indicated that they adopted different stances against the three agents. The contrast of brain activity during interaction with the artificial and the random agents didn't yield any cluster at the threshold used, suggesting the absence of a reproducible stance when interacting with an artificial intelligence. We probed response to the artificial agent in regions of interest corresponding to clusters found in the contrast between the intentional and the random agents. In the precuneus involved in working memory, the posterior intraparietal suclus, in the control of attention and the dorsolateral prefrontal cortex, in executive functions, brain activity for Art was larger than for Rnd but lower than for Int, supporting the intrinsically engaging nature of social interactions. A similar pattern in the left premotor cortex and anterior intraparietal sulcus involved in motor resonance suggested that participants simulated human, and to a lesser extend humanoid robot actions, when playing the game. Finally, mentalizing regions, the medial prefrontal cortex and right temporoparietal junction, responded to the human only, supporting the specificity of mentalizing areas for interactions with intentional agents.

Fidelity decay in interacting two-level boson systems: Freezing and revivals

NASA Astrophysics Data System (ADS)

Benet, Luis; Hernández-Quiroz, Saúl; Seligman, Thomas H.

2011-05-01

We study the fidelity decay in the k-body embedded ensembles of random matrices for bosons distributed in two single-particle states, considering the reference or unperturbed Hamiltonian as the one-body terms and the diagonal part of the k-body embedded ensemble of random matrices and the perturbation as the residual off-diagonal part of the interaction. We calculate the ensemble-averaged fidelity with respect to an initial random state within linear response theory to second order on the perturbation strength and demonstrate that it displays the freeze of the fidelity. During the freeze, the average fidelity exhibits periodic revivals at integer values of the Heisenberg time tH. By selecting specific k-body terms of the residual interaction, we find that the periodicity of the revivals during the freeze of fidelity is an integer fraction of tH, thus relating the period of the revivals with the range of the interaction k of the perturbing terms. Numerical calculations confirm the analytical results.

Interaction of the sonic boom with atmospheric turbulence

NASA Technical Reports Server (NTRS)

Rusak, Zvi; Cole, Julian D.

1994-01-01

Theoretical research was carried out to study the effect of free-stream turbulence on sonic boom pressure fields. A new transonic small-disturbance model to analyze the interactions of random disturbances with a weak shock was developed. The model equation has an extended form of the classic small-disturbance equation for unsteady transonic aerodynamics. An alternative approach shows that the pressure field may be described by an equation that has an extended form of the classic nonlinear acoustics equation that describes the propagation of sound beams with narrow angular spectrum. The model shows that diffraction effects, nonlinear steepening effects, focusing and caustic effects and random induced vorticity fluctuations interact simultaneously to determine the development of the shock wave in space and time and the pressure field behind it. A finite-difference algorithm to solve the mixed type elliptic-hyperbolic flows around the shock wave was also developed. Numerical calculations of shock wave interactions with various deterministic and random fluctuations will be presented in a future report.

Random catalytic reaction networks

NASA Astrophysics Data System (ADS)

Stadler, Peter F.; Fontana, Walter; Miller, John H.

1993-03-01

We study networks that are a generalization of replicator (or Lotka-Volterra) equations. They model the dynamics of a population of object types whose binary interactions determine the specific type of interaction product. Such a system always reduces its dimension to a subset that contains production pathways for all of its members. The network equation can be rewritten at a level of collectives in terms of two basic interaction patterns: replicator sets and cyclic transformation pathways among sets. Although the system contains well-known cases that exhibit very complicated dynamics, the generic behavior of randomly generated systems is found (numerically) to be extremely robust: convergence to a globally stable rest point. It is easy to tailor networks that display replicator interactions where the replicators are entire self-sustaining subsystems, rather than structureless units. A numerical scan of random systems highlights the special properties of elementary replicators: they reduce the effective interconnectedness of the system, resulting in enhanced competition, and strong correlations between the concentrations.

Many-body delocalization with random vector potentials

NASA Astrophysics Data System (ADS)

Cheng, Chen; Mondaini, Rubem

In this talk we present the ergodic properties of excited states in a model of interacting fermions in quasi-one dimensional chains subjected to a random vector potential. In the non-interacting limit, we show that arbitrarily small values of this complex off-diagonal disorder triggers localization for the whole spectrum; the divergence of the localization length in the single particle basis is characterized by a critical exponent ν which depends on the energy density being investigated. However, when short-ranged interactions are included, the localization is lost and the system is ergodic regardless of the magnitude of disorder in finite chains. Our numerical results suggest a delocalization scheme for arbitrary small values of interactions. This finding indicates that the standard scenario of the many-body localization cannot be obtained in a model with random gauge fields. This research is financially supported by the National Natural Science Foundation of China (NSFC) (Grant Nos. U1530401 and 11674021). RM also acknowledges support from NSFC (Grant No. 11650110441).

Analysis of esterified and nonesterified fatty acids in serum from obese individuals after intake of breakfasts prepared with oils heated at frying temperature.

PubMed

Orozco-Solano, M I; Priego-Capote, F; Luque de Castro, M D

2013-07-01

In this study, levels of esterified and nonesterified fatty acids (EFAs and NEFAs, respectively) were compared in obese individuals (body mass index between 30 and 47 kg m(-2)) in basal state and after intake of four different breakfasts prepared with oils heated at frying temperature. The target oils were three sunflower oils--pure, enriched with dimethylsiloxane (400 μg mL(-1)) as lipophilic oxidation inhibitor, and enriched with phenolic compounds (400 μg mL(-1)) as hydrophilic oxidation inhibitors--and virgin olive oil with a natural content of phenolic compounds of 400 μg mL(-1). The intake of breakfasts was randomized to avoid trends associated to this variability source. EFAs and NEFAs were subjected to a sequential derivatization step for independent gas chromatography-mass spectrometry analysis of both fractions of metabolites in human serum. Derivatization was assisted by ultrasonic energy to accelerate the reaction kinetics, as required for high-throughput analysis. Statistical analysis supported on univariate (multifactor ANOVA) and multivariate approaches (principal component analysis and partial least squares-discriminant analysis) allowed identification of the main variability sources and also discriminating between individuals after intake of each breakfast. Individuals' samples after intake of breakfasts prepared with virgin olive oil were clearly separated from those who ingested the remaining breakfasts. The main compounds contributing to discrimination were omega-3 and omega-6 EFAs with special emphasis on arachidonic acid and eicosapentaenoic acid. These two polyunsaturated fatty acids are the precursors of eicosanoid metabolites, which are of vital importance as they play important roles in inflammation and in the pathogenesis of vascular and malignant diseases as cancer.

The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors.

PubMed

Liu, Xueqin; Li, Ning; Yuan, Shuai; Xu, Ning; Shi, Wenqin; Chen, Weibin

2015-12-15

As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. Copyright © 2015 Elsevier B.V. All rights reserved.

Port-site metastasis after laparoscopic surgery for colorectal cancer--still a real concern? Case report and review of the literature.

PubMed

Bărbulescu, M; Alecu, L; Boeţi, P; Popescu, I

2012-01-01

The recently published long-term oncological results of the large multicentric randomized prospective trials, such as COST, COLOR, and UK MRC CLASICC, have diminished once more the initial skepticism from the mid '90s, regarding the safety of laparoscopic approach for colorectal cancer surgery. The actual incidence of port-site metastases (PMSs) in the laparoscopic surgery for colorectal cancer is just arround 1%, being statistically simmilar to the wound metastases after open colorectal surgery. We followed up a series of 122 laparoscopic-assisted resections for colorectal adenocarcinoma, 49 for rectal cancer and 73 for colon cancer. The operations were performed at the Center of Digestive Diseases and Liver Transplantation, Fundeni Clinical Institute, Bucharest, Romania, between 1st January 2002 and 31st december 2008. There was only one case of PMS (0.81%). A 83-year old man developed a recurrent parietal tumor on the site of extraction minilaparotomy, 4 months after laparoscopic-assisted right hemicolectomy for a Dukes C, poorly differentiated (G3) adenocarcinoma of the cecum. We have reviewed the scientific relevant literature regarding the incidence and multi-factor etiology of PMSs in the laparoscopic surgery for colorectal cancer as well as the methods suggested for prevention of parietal tumour dissemination to the trocar or wound sites. PMSs consecutive to laparoscopic surgery for colorectal cancer are no longer a big concern enough to contraindicate this beneficial surgery for oncological reasons. However, PMSs continue to represent a reality which must be taken into consideration by any laparoscopic surgeon. There are different prevention measures that should be applied for reducing the occurence of this possible complication.

National Survey of Yoga Practitioners: Mental and Physical Health Benefits

PubMed Central

Ross, Alyson; Friedmann, Erika; Bevans, Margaret; Thomas, Sue

2013-01-01

Summary Objectives to describe yoga practice and health characteristics of individuals who practice yoga, and to explore their beliefs regarding the effects of their yoga practice on their health. Design a cross-sectional design with anonymous online surveys Setting 4307 randomly selected individuals from 15 US Iyengar yoga studios (n = 18,160), representing 41 states; 1087 individuals responded, with 1045 (24.3%) surveys completed. Outcome Measures Freiberg Mindfulness Inventory, Mental Health Continuum (subjective well-being), Multi-factor Screener (diet), PROMIS sleep disturbance, fatigue, and social support, International Physical Activity Questionnaire. Results Age: 19 to 87 years (M = 51.7 ± 11.7), 84.2% female, 89.2% white, 87.4% well educated (≥ bachelor’s degree). Mean years of yoga practice = 11.4 (± 7.5). BMI = 12.1–49.4 (M = 23.1 ± 3.9). Levels of obesity (4.9%), smoking (2%), and fruit and vegetable consumption (M = 6.1 ± 1.1) were favorable compared to national norms. 60% reported at least one chronic/serious health condition, yet most reported very good (46.3%) or excellent (38.8%) general health. Despite high levels of depression (24.8 %), nearly all were moderately mentally healthy (55.2%) or flourishing (43.8%). Participants agreed yoga improved: energy (84.5%), happiness (86.5%), social relationships (67%), sleep (68.5%), and weight (57.3%), and beliefs did not differ substantially according to race or gender. The more they practiced yoga, whether in years or in amount of class or home practice, the higher their odds of believing yoga improved their health. Conclusions Individuals who practice yoga are not free of health concerns, but most believe their health improved because of yoga. Yoga might be beneficial for a number of populations including elderly women and those with chronic health conditions. PMID:23876562

The interactive effects of genetic polymorphisms within LFA-1/ICAM-1/GSK-3β pathway and environmental hazards on the development of Graves' opthalmopathy.

PubMed

Yang, Ge; Fu, Yang; Lu, Xiaoyan; Wang, Menghua; Dong, Hongtao; Li, Qiuming

2018-05-22

The purpose of this investigation was to explore the combined effects of single nucleotide polymorphisms (SNPs) within LFA-1/ICAM-1/GSK-3β pathway and environmental hazards on susceptibility to Graves' opthalmopathy (GO) among a Chinese Han population. Altogether 305 GO patients and 283 Graves' disease (GD) subjects were recruited. Information relevant to the participants' age, gender, body mass index (BMI), regular physical activity, smoking history, alcohol intake, stressful work environment, stress at work, family history of thyroid disease and 131 I treatment were summarized, and the participants' related SNPs of LFA-1/ICAM-1/GSK-3β were also detected. Then the gene-gene and gene-environment interactions were evaluated by logistic regression model and multi-factor dimensionality reduction (MDR) modeling. The results exhibited that age, BMI, smoking history, stressful work, stress at home, family history of thyroid disease and 131 I treatment appeared as potential indicators regulating GO risk, when either univariate or multivariate regression analysis was performed (all P < 0.05). Moreover, rs12716977 (T > C) and rs2230433 (G > C) of LFA-1, rs1799969 (G > A) and rs5498 (A > G) of ICAM-1, as well as rs6438552 (T > C) and rs334558 (T > C) of GSK-3β were significantly associated with altered susceptibility to GO under the allelic models (all P < 0.05). Also haplotype TGAATC acted as a protective factor against GO risk (P < 0.05), whereas haplotype CGAACC largely elevated risk of GO (P < 0.05). Besides, logistic regression analysis demonstrated that rs12716927, rs5498 and rs6438552 all would affect the influences exerted by age, BMI, smoking history, stressful work, stress at home, family history of thyroid disease or 131 I treatment on GO susceptibility (all P < 0.05). MDR modeling implied that the combined model of rs12716977, rs2230433 and rs1799969 was the supreme interactive model when BMI was co-assessed, and the interactive model of rs12716977, rs334558 and rs5491 was the most desirable among the smoking population. In conclusion, gene-gene and gene-environment interactions served as a crucial manner in affecting susceptibility to GO, providing solid evidences for screening effective GO-susceptible biomarkers and exploring potential GO treatment strategies. Copyright © 2018. Published by Elsevier Ltd.

Genetic variants of JNK and p38α pathways and risk of non-small cell lung cancer in an Eastern Chinese population.

PubMed

Jia, Ming; Zhu, Meiling; Zhou, Fei; Wang, Mengyun; Sun, Menghong; Yang, Yajun; Wang, Xiaofeng; Wang, Jiucun; Jin, Li; Xiang, Jiaqing; Zhang, Yawei; Chang, Jianhua; Wei, Qingyi

2017-02-15

The JNK and p38α pathways play an important role in carcinogenesis. Therefore, we hypothesize that single nucleotide polymorphisms (SNPs) of genes involved in these pathways are associated with risk of lung cancer. We first selected and genotyped 11 independent SNPs of the JNK and p38α pathway-related genes in a discovery set of 1,002 non-small cell lung cancer (NSCLC) cases and 1,025 cancer-free controls of Eastern Chinese. Then, we validated those significant SNPs in a replication set of 1,333 NSCLC cases and 1,339 cancer-free controls of Eastern Chinese. Multifactor dimensionality reduction (MDR) and classification and regression tree (CART) analyses were used to identify interactions between significant SNPs and other covariates. In both discovery and replication as well as their pooled analysis, carriers of GADD45G rs8252T variant genotypes had a significantly lower risk of NSCLC (adjusted OR = 0.81 and 0.79, 95% CI = 0.72-0.92 and 0.64-0.99 and p = 0.001 and 0.040 for dominant and recessive genetic models, respectively) and carriers of MAP2K7 rs3679T variant genotypes had an increased risk of NSCLC (adjusted OR = 1.19 and 1.29, 95% CI = 1.05-1.34 and 1.09-1.54 and p = 0.005 and 0.004 for dominant and recessive genetic models, respectively). Furthermore, rs8252 variant CT/TT carriers showed significantly higher levels of GADD45G mRNA expression than CC carriers in the target tissues. We observed some evidence of interactions between rs8252 genotypes and sex in NSCLC risk. These results indicate that GADD45G rs8252 and MAP2K7 rs3679 SNPs may be susceptibility biomarkers for NSCLC in Eastern Chinese populations. © 2016 UICC.

Linking global-change induced shifts in soil nitrogen cycling with the abundance of key microorganisms

NASA Astrophysics Data System (ADS)

Carey, C.; Eviner, V.; Beman, M.; Hart, S. C.

2013-12-01

Since western colonization, the ecology of California has seen marked transformations. In particular, invasion of terrestrial ecosystems by exotic plants has altered plant community composition, disturbances, soil hydrologic regimes, and nutrient cycling. In addition, as a result of fertilization and combustion of fossil fuels, California experiences some of the highest nitrogen (N) deposition rates in the country. Land use has also changed with the introduction of domestic livestock grazing about 250 years ago. Currently, approximately 32% of land in California experiences grazing pressure. These ecological changes likely affect the ecosystems of California simultaneously. However, with multifactor global change experiments in their infancy, little is known about potential interactive effects on ecosystem structure and function. Our study measured the response of soil N dynamics to a unique combination of treatments: invasion by exotic plants (Aegilops triuncialis and Taeniatherum caput-medusae), elevated N additions, and simulated cattle grazing (aboveground vegetation removal). In addition, we quantified the abundance of key functional genes involved in nitrification (amoA) and denitrification (nirS/nirK) in order to gain a mechanistic insight into changes in ecosystem functioning. We found that, while responses of soil N pools and processes to global change factors tend to be dominated by main effects, interactions among factors can substantially alter the overall response of the ecosystem. For instance, N additions increased potential nitrification and pools of total inorganic N (TIN; NH4+ and NO3-); when N additions and grazing were combined, however, nitrification potentials and TIN decreased to those of ambient N (control) levels. Additionally, neither N additions nor simulated grazing independently affected soil microbial biomass of invaded plots; yet, when combined, the microbial biomass increased significantly. Our results help to provide a better understanding of the regulatory role of the soil microbial community in terrestrial N cycling and also help to improve our understanding of the controls on global change-induced shifts in ecosystem functioning.

Effects of three global change drivers on terrestrial C:N:P stoichiometry: a global synthesis.

PubMed

Yue, Kai; Fornara, Dario A; Yang, Wanqin; Peng, Yan; Li, Zhijie; Wu, Fuzhong; Peng, Changhui

2017-06-01

Over the last few decades, there has been an increasing number of controlled-manipulative experiments to investigate how plants and soils might respond to global change. These experiments typically examined the effects of each of three global change drivers [i.e., nitrogen (N) deposition, warming, and elevated CO 2 ] on primary productivity and on the biogeochemistry of carbon (C), N, and phosphorus (P) across different terrestrial ecosystems. Here, we capitalize on this large amount of information by performing a comprehensive meta-analysis (>2000 case studies worldwide) to address how C:N:P stoichiometry of plants, soils, and soil microbial biomass might respond to individual vs. combined effects of the three global change drivers. Our results show that (i) individual effects of N addition and elevated CO 2 on C:N:P stoichiometry are stronger than warming, (ii) combined effects of pairs of global change drivers (e.g., N addition + elevated CO 2 , warming + elevated CO 2 ) on C:N:P stoichiometry were generally weaker than the individual effects of each of these drivers, (iii) additive interactions (i.e., when combined effects are equal to or not significantly different from the sum of individual effects) were more common than synergistic or antagonistic interactions, (iv) C:N:P stoichiometry of soil and soil microbial biomass shows high homeostasis under global change manipulations, and (v) C:N:P responses to global change are strongly affected by ecosystem type, local climate, and experimental conditions. Our study is one of the first to compare individual vs. combined effects of the three global change drivers on terrestrial C:N:P ratios using a large set of data. To further improve our understanding of how ecosystems might respond to future global change, long-term ecosystem-scale studies testing multifactor effects on plants and soils are urgently required across different world regions. © 2017 John Wiley & Sons Ltd.

Complex carbon cycle responses to multi-level warming and supplemental summer rain in the high Arctic.

PubMed

Sharp, Elizabeth D; Sullivan, Patrick F; Steltzer, Heidi; Csank, Adam Z; Welker, Jeffrey M

2013-06-01

The Arctic has experienced rapid warming and, although there are uncertainties, increases in precipitation are projected to accompany future warming. Climate changes are expected to affect magnitudes of gross ecosystem photosynthesis (GEP), ecosystem respiration (ER) and the net ecosystem exchange of CO2 (NEE). Furthermore, ecosystem responses to climate change are likely to be characterized by nonlinearities, thresholds and interactions among system components and the driving variables. These complex interactions increase the difficulty of predicting responses to climate change and necessitate the use of manipulative experiments. In 2003, we established a long-term, multi-level and multi-factor climate change experiment in a polar semidesert in northwest Greenland. Two levels of heating (30 and 60 W m(-2) ) were applied and the higher level was combined with supplemental summer rain. We made plot-level measurements of CO2 exchange, plant community composition, foliar nitrogen concentrations, leaf δ(13) C and NDVI to examine responses to our treatments at ecosystem- and leaf-levels. We confronted simple models of GEP and ER with our data to test hypotheses regarding key drivers of CO2 exchange and to estimate growing season CO2 -C budgets. Low-level warming increased the magnitude of the ecosystem C sink. Meanwhile, high-level warming made the ecosystem a source of C to the atmosphere. When high-level warming was combined with increased summer rain, the ecosystem became a C sink of magnitude similar to that observed under low-level warming. Competition among our ER models revealed the importance of soil moisture as a driving variable, likely through its effects on microbial activity and nutrient cycling. Measurements of community composition and proxies for leaf-level physiology suggest GEP responses largely reflect changes in leaf area of Salix arctica, rather than changes in leaf-level physiology. Our findings indicate that the sign and magnitude of the future High Arctic C budget may depend upon changes in summer rain. © 2013 Blackwell Publishing Ltd.

Association of single nucleotide polymorphisms in CACNA 1A/CACNA 1C/CACNA 1H calcium channel genes with diabetic peripheral neuropathy in Chinese population.

PubMed

Sun, Lin; Ma, Jun; Mao, Qian; Yang, Yun-Long; Ma, Lin-Lin; Niu, Ling; Liu, Li-Feng

2018-06-29

The present study was conducted to explore the correlations between single nucleotide polymorphisms (SNPs) in the calcium channel CACNA 1A, CACNA 1C, and CACNA 1H genes and diabetic peripheral neuropathy (DPN) amongst the Chinese population. In total, 281 patients diagnosed with type 2 diabetes participated in the present study. These patients were divided into the case group, which was subdivided into the DPN (143 cases) and the non-DPN groups (138 cases). Subsequently, 180 healthy individuals that had undergone routine health examinations were also recruited and assigned to the control group. PCR-restriction fragment length polymorphism (PCR-RFLP) was used to detect the genotype and allele frequencies of CACNA 1A, CACNA 1C, and CACNA 1H genes; logistic regression analysis to investigate the association of gene polymorphisms with DNP. Gene-gene interactions were then detected by generalized multifactor dimensionality reduction (GMDR). The results revealed that CACNA 1A rs2248069 and rsl6030, CACNA 1C rs216008 and rs2239050, and CACNA 1H rs3794619, and rs7191246 SNPs were all associated with DPN, while rs2248069, rsl6030, rs2239050, and rs7191246 polymorphisms were attributed to the susceptibility to DPN. It was also observed that the optimal models were three-, four- and five-dimensional models with a prediction accuracy of 61.05% and the greatest consistency of cross-validation was 10/10. In summary, these findings demonstrated that the SNPs in the CACNA 1A, CACNA 1C, and CACNA 1H genes were involved in the pathophysiology of DPN. In addition, polymorphisms in the CACNA 1A, CACNA 1C, and CACNA 1H genes and their interactions also had effects on DPN. © 2018 The Author(s).

Diffusion, subdiffusion, and localization of active colloids in random post lattices

NASA Astrophysics Data System (ADS)

Morin, Alexandre; Lopes Cardozo, David; Chikkadi, Vijayakumar; Bartolo, Denis

2017-10-01

Combining experiments and theory, we address the dynamics of self-propelled particles in crowded environments. We first demonstrate that motile colloids cruising at constant speed through random lattices undergo a smooth transition from diffusive to subdiffusive to localized dynamics upon increasing the obstacle density. We then elucidate the nature of these transitions by performing extensive simulations constructed from a detailed analysis of the colloid-obstacle interactions. We evidence that repulsion at a distance and hard-core interactions both contribute to slowing down the long-time diffusion of the colloids. In contrast, the localization transition stems solely from excluded-volume interactions and occurs at the void-percolation threshold. Within this critical scenario, equivalent to that of the random Lorentz gas, genuine asymptotic subdiffusion is found only at the critical density where the motile particles explore a fractal maze.

Nature of magnetization and lateral spin-orbit interaction in gated semiconductor nanowires.

PubMed

Karlsson, H; Yakimenko, I I; Berggren, K-F

2018-05-31

Semiconductor nanowires are interesting candidates for realization of spintronics devices. In this paper we study electronic states and effects of lateral spin-orbit coupling (LSOC) in a one-dimensional asymmetrically biased nanowire using the Hartree-Fock method with Dirac interaction. We have shown that spin polarization can be triggered by LSOC at finite source-drain bias,as a result of numerical noise representing a random magnetic field due to wiring or a random background magnetic field by Earth magnetic field, for instance. The electrons spontaneously arrange into spin rows in the wire due to electron interactions leading to a finite spin polarization. The direction of polarization is, however, random at zero source-drain bias. We have found that LSOC has an effect on orientation of spin rows only in the case when source-drain bias is applied.

Nature of magnetization and lateral spin–orbit interaction in gated semiconductor nanowires

NASA Astrophysics Data System (ADS)

Karlsson, H.; Yakimenko, I. I.; Berggren, K.-F.

2018-05-01

Semiconductor nanowires are interesting candidates for realization of spintronics devices. In this paper we study electronic states and effects of lateral spin–orbit coupling (LSOC) in a one-dimensional asymmetrically biased nanowire using the Hartree–Fock method with Dirac interaction. We have shown that spin polarization can be triggered by LSOC at finite source-drain bias,as a result of numerical noise representing a random magnetic field due to wiring or a random background magnetic field by Earth magnetic field, for instance. The electrons spontaneously arrange into spin rows in the wire due to electron interactions leading to a finite spin polarization. The direction of polarization is, however, random at zero source-drain bias. We have found that LSOC has an effect on orientation of spin rows only in the case when source-drain bias is applied.

You Look Human, But Act Like a Machine: Agent Appearance and Behavior Modulate Different Aspects of Human-Robot Interaction.

PubMed

Abubshait, Abdulaziz; Wiese, Eva

2017-01-01

Gaze following occurs automatically in social interactions, but the degree to which gaze is followed depends on whether an agent is perceived to have a mind, making its behavior socially more relevant for the interaction. Mind perception also modulates the attitudes we have toward others, and determines the degree of empathy, prosociality, and morality invested in social interactions. Seeing mind in others is not exclusive to human agents, but mind can also be ascribed to non-human agents like robots, as long as their appearance and/or behavior allows them to be perceived as intentional beings. Previous studies have shown that human appearance and reliable behavior induce mind perception to robot agents, and positively affect attitudes and performance in human-robot interaction. What has not been investigated so far is whether different triggers of mind perception have an independent or interactive effect on attitudes and performance in human-robot interaction. We examine this question by manipulating agent appearance (human vs. robot) and behavior (reliable vs. random) within the same paradigm and examine how congruent (human/reliable vs. robot/random) versus incongruent (human/random vs. robot/reliable) combinations of these triggers affect performance (i.e., gaze following) and attitudes (i.e., agent ratings) in human-robot interaction. The results show that both appearance and behavior affect human-robot interaction but that the two triggers seem to operate in isolation, with appearance more strongly impacting attitudes, and behavior more strongly affecting performance. The implications of these findings for human-robot interaction are discussed.

Oscillations and chaos in neural networks: an exactly solvable model.

PubMed Central

Wang, L P; Pichler, E E; Ross, J

1990-01-01

We consider a randomly diluted higher-order network with noise, consisting of McCulloch-Pitts neurons that interact by Hebbian-type connections. For this model, exact dynamical equations are derived and solved for both parallel and random sequential updating algorithms. For parallel dynamics, we find a rich spectrum of different behaviors including static retrieving and oscillatory and chaotic phenomena in different parts of the parameter space. The bifurcation parameters include first- and second-order neuronal interaction coefficients and a rescaled noise level, which represents the combined effects of the random synaptic dilution, interference between stored patterns, and additional background noise. We show that a marked difference in terms of the occurrence of oscillations or chaos exists between neural networks with parallel and random sequential dynamics. Images PMID:2251287

Study of Pharmacodynamic and Pharmacokinetic Interaction of Bojungikki-Tang with Aspirin in Healthy Subjects and Ischemic Stroke Patients

PubMed Central

Yoo, Jung-Hwa; Yim, Sung-Vin

2018-01-01

Background Bojungikki-tang (BJIKT) is a widely used traditional herbal formula in China, Japan, and Korea. There have been reports that several herbs among BJIKT have interactions with antiplatelet drugs, such as aspirin. This study aimed to assess whether BJIKT interacts with aspirin in terms of pharmacokinetics (PK) and pharmacodynamics (PD) in healthy subjects and ischemic stroke patients. Methods The phase I interaction trial was a randomized, open-label, crossover study of 10 healthy male subjects, and the phase III interaction trial was a randomized, placebo-controlled, parallel study of 43 ischemic stroke patients. Each participant randomly received aspirin + BJIKT or aspirin + placebo. For PK analysis, plasma acetyl salicylic acid (ASA) and salicylic acid (SA) were evaluated, and, for PD analysis, platelet aggregation and plasma thromboxane B2 (TxB2) were measured. Results In the PK parameters, mean area under curve, maximum concertation, and peak concentration time of ASA and SA were not different between two groups in healthy subjects and ischemic stroke patients. In the PD profiles, TxB2 concentrations and platelet aggregation were not affected by coadministration of BJIKT in healthy subjects and ischemic stroke patients. Conclusions These results suggest that coadministration of BJIKT with aspirin may not result in herb-drug interaction. PMID:29599812

[Dentinal hypersensitivity in periodontal disease. Aetiology Aetiology--management].

PubMed

Andronikaki-Faldani, A; Kamma, I

1988-01-01

The exposure of dentine has a multifactoral aetiology and pain may frequently be elicited by a number of stimuli. Management of dentinal hypersensitivity tends to be empirical because of the lack of knowledge concerning the mechanism of pain transmission through dentine. Nevertheless, whichever theory proves to be correct, occlusion of dentinal tubules would appear an essential prerequisite for an effective desensitising agent. A large number of compounds as well as iontophoresis have been employed in the management of dentinal hypersensitivity. These desensitising agents are: sodium, fluoride, stannous fluoride, sodium monofluorophosphate, strontium chloride, calcium hydroxide, potassium nitrate, silver nitrate, formalin, corticosteroids, resins, varnishes and glass ionomers. The most effective of the compounds mentioned above, are fluorides used as gels, varnishes, mouthwashes or toothpastes, strontium chloride and potassium nitrate.

[Treatment of acne with consequences -- pseudotumor cerebri due to hypervitaminosis A].

PubMed

Meyer-Heim, A; Landau, K; Boltshauser, E

2002-01-09

Pseudotumor cerebri (PTC) is an entity characterized by elevated intracranial pressure of probably multifactoral origin, but most cases remain idiopathic. We report a 15-year-old girl with PTC due to prolonged consumption of Arovit (Vitamin A) for treatment of acne. The diagnosis was established by measuring raised cerebrospinal fluid pressure after an intracranial mass lesion and dural venous sinsus thrombosis were excluded. The increased level of vitamin A confirmed the diagnosis of hypervitaminosis A as the causative pathogen. The patient was treated with lumbar punctures and acetazolamide (Diamox). PTC due to hypervitaminosis A is a serious complication, which can cause permanent visual impairment. Patients treated with retinoids require proper surveillance. The elevated serum level of retinoids after withdrawal may persist for weeks.

Workshop on multifactor aging mechanisms and models

NASA Astrophysics Data System (ADS)

Agarwal, V. K.

1992-10-01

There have been considerable efforts to understand the aging and failure mechanisms of insulation in electrical systems. However, progress has been slow because of the complex nature of the subject particularly when dealing with multiple stresses e.g. electrical, thermal, mechanical, radiation, humidity and other environmental factors. When an insulating material is exposed to just one stress factor e.g. electric field, one must devise test(s) which are not only economically efficient and practical but which take into account the nature of electric field (ac, dc and pulsed), duration and level or field strength, and field configurations. Any additional stress factor(s) make the matrix of measurements and the understanding of resulting degradation processes more complex, time consuming and expensive.

Transformational leadership and moral reasoning.

PubMed

Turner, Nick; Barling, Julian; Epitropaki, Olga; Butcher, Vicky; Milner, Caroline

2002-04-01

Terms such as moral and ethical leadership are used widely in theory, yet little systematic research has related a sociomoral dimension to leadership in organizations. This study investigated whether managers' moral reasoning (n = 132) was associated with the transformational and transactional leadership behaviors they exhibited as perceived by their subordinates (n = 407). Managers completed the Defining Issues Test (J. R. Rest, 1990), whereas their subordinates completed the Multifactor Leadership Questionnaire (B. M. Bass & B. J. Avolio, 1995). Analysis of covariance indicated that managers scoring in the highest group of the moral-reasoning distribution exhibited more transformational leadership behaviors than leaders scoring in the lowest group. As expected, there was no relationship between moral-reasoning group and transactional leadership behaviors. Implications for leadership development are discussed.

Landau instability and mobility edges of the interacting one-dimensional Bose gas in weak random potentials

NASA Astrophysics Data System (ADS)

Cherny, Alexander Yu; Caux, Jean-Sébastien; Brand, Joachim

2018-01-01

We study the frictional force exerted on the trapped, interacting 1D Bose gas under the influence of a moving random potential. Specifically we consider weak potentials generated by optical speckle patterns with finite correlation length. We show that repulsive interactions between bosons lead to a superfluid response and suppression of frictional force, which can inhibit the onset of Anderson localisation. We perform a quantitative analysis of the Landau instability based on the dynamic structure factor of the integrable Lieb-Liniger model and demonstrate the existence of effective mobility edges.

Binocular interactions in random chromatic changes at isoluminance

NASA Astrophysics Data System (ADS)

Medina, José M.

2006-02-01

To examine the type of chromatic interactions at isoluminance in the phenomenon of binocular vision, I have determined simple visual reaction times (VRT) under three observational conditions (monocular left, monocular right, and binocular) for different chromatic stimuli along random color axes at isoluminance (simultaneous L-, M-, and S-cone variations). Upper and lower boundaries of probability summation as well as the binocular capacity coefficient were estimated with observed distributions of reaction times. The results were not consistent with the notion of independent chromatic channels between eyes, suggesting the existence of excitatory and inhibitory binocular interactions at suprathreshold isoluminance conditions.

Two spatial light modulator system for laboratory simulation of random beam propagation in random media.

PubMed

Wang, Fei; Toselli, Italo; Korotkova, Olga

2016-02-10

An optical system consisting of a laser source and two independent consecutive phase-only spatial light modulators (SLMs) is shown to accurately simulate a generated random beam (first SLM) after interaction with a stationary random medium (second SLM). To illustrate the range of possibilities, a recently introduced class of random optical frames is examined on propagation in free space and several weak turbulent channels with Kolmogorov and non-Kolmogorov statistics.

Effect of matrix chemical heterogeneity on effective filler interactions in model polymer nanocomposites

NASA Astrophysics Data System (ADS)

Hall, Lisa; Schweizer, Kenneth

2010-03-01

The microscopic Polymer Reference Interaction Site Model theory has been applied to spherical and rodlike fillers dissolved in three types of chemically heterogeneous polymer melts: alternating AB copolymer, random AB copolymers, and an equimolar blend of two homopolymers. In each case, one monomer species adsorbs more strongly on the filler mimicking a specific attraction, while all inter-monomer potentials are hard core which precludes macrophase or microphase separation. Qualitative differences in the filler potential-of-mean force are predicted relative to the homopolymer case. The adsorbed bound layer for alternating copolymers exhibits a spatial moduluation or layering effect but is otherwise similar to that of the homopolymer system. Random copolymers and the polymer blend mediate a novel strong, long-range bridging interaction between fillers at moderate to high adsorption strengths. The bridging strength is a non-monotonic function of random copolymer composition, reflecting subtle competing enthalpic and entropic considerations.

Impacts of elevated atmospheric CO2 and O3 on forests: phytochemistry, trophic interactions, and ecosystem dynamics.

PubMed

Lindroth, Richard L

2010-01-01

Prominent among the many factors now affecting the sustainability of forest ecosystems are anthropogenically-generated carbon dioxide (CO2) and ozone (O3). CO2 is the substrate for photosynthesis and thus can accelerate tree growth, whereas O3 is a highly reactive oxygen species and interferes with basic physiological functions. This review summarizes the impacts of CO2 and O3 on tree chemical composition and highlights the consequences thereof for trophic interactions and ecosystem dynamics. CO2 and O3 influence phytochemical composition by altering substrate availability and biochemical/physiological processes such as photosynthesis and defense signaling pathways. Growth of trees under enriched CO2 generally leads to an increase in the C/N ratio, due to a decline in foliar nitrogen and concomitant increases in carbohydrates and phenolics. Terpenoid levels generally are not affected by atmospheric CO2 concentration. O3 triggers up-regulation of antioxidant defense pathways, leading to the production of simple phenolics and flavonoids (more so in angiosperms than gymnosperms). Tannins levels generally are unaffected, while terpenoids exhibit variable responses. In combination, CO2 and O3 exert both additive and interactive effects on tree chemical composition. CO2-and O3-mediated changes in plant chemistry influence host selection, individual performance (development, growth, reproduction), and population densities of herbivores (primarily phytophagous insects) and soil invertebrates. These changes can effect shifts in the amount and temporal pattern of forest canopy damage and organic substrate deposition. Decomposition rates of leaf litter produced under elevated CO2 and O3 may or may not be altered, and can respond to both the independent and interactive effects of the pollutants. Overall, however, CO2 and O3 effects on decomposition will be influenced more by their impacts on the quantity, rather than quality, of litter produced. A prominent theme to emerge from this and related reviews is that the effects of elevated CO2 and O3 on plant chemistry and ecological interactions are highly context- and species-specific, thus frustrating attempts to identify general, global patterns. Many of the interactions that govern above- and below-ground community and ecosystem processes are chemically mediated, ultimately influencing terrestrial carbon sequestration and feeding back to influence atmospheric composition. Thus, the discipline of chemical ecology is fundamentally important for elucidating the impacts of humans on the health and sustainability of forest ecosystems. Future research should seek to increase the diversity of natural products, species, and biomes studied; incorporate long-term, multi-factor experiments; and employ a comprehensive “genes to ecosystems” perspective that couples genetic/genomic tools with the approaches of evolutionary and ecosystem ecology.

Epidemic spreading on random surfer networks with optimal interaction radius

NASA Astrophysics Data System (ADS)

Feng, Yun; Ding, Li; Hu, Ping

2018-03-01

In this paper, the optimal control problem of epidemic spreading on random surfer heterogeneous networks is considered. An epidemic spreading model is established according to the classification of individual's initial interaction radii. Then, a control strategy is proposed based on adjusting individual's interaction radii. The global stability of the disease free and endemic equilibrium of the model is investigated. We prove that an optimal solution exists for the optimal control problem and the explicit form of which is presented. Numerical simulations are conducted to verify the correctness of the theoretical results. It is proved that the optimal control strategy is effective to minimize the density of infected individuals and the cost associated with the adjustment of interaction radii.

Non-random nectar unloading interactions between foragers and their receivers in the honeybee hive

NASA Astrophysics Data System (ADS)

Goyret, Joaquín; Farina, Walter M.

2005-09-01

Nectar acquisition in the honeybee Apis mellifera is a partitioned task in which foragers gather nectar and bring it to the hive, where nest mates unload via trophallaxis (i.e. mouth-to-mouth transfer) the collected food for further storage. Because forager mates exploit different feeding places simultaneously, this study addresses the question of whether nectar unloading interactions between foragers and hive-bees are established randomly, as it is commonly assumed. Two groups of foragers were trained to exploit a different scented food source for 5 days. We recorded their trophallaxes with hive-mates, marking the latter ones according to the forager group they were unloading. We found non-random probabilities for the occurrence of trophallaxes between experimental foragers and hive-bees, instead, we found that trophallactic interactions were more likely to involve groups of individuals which had formerly interacted orally. We propose that olfactory cues present in the transferred nectar promoted the observed bias, and we discuss this bias in the context of the organization of nectar acquisition: a partitioned task carried out in a decentralized insect society.

Exact solution of two interacting run-and-tumble random walkers with finite tumble duration

NASA Astrophysics Data System (ADS)

Slowman, A. B.; Evans, M. R.; Blythe, R. A.

2017-09-01

We study a model of interacting run-and-tumble random walkers operating under mutual hardcore exclusion on a one-dimensional lattice with periodic boundary conditions. We incorporate a finite, poisson-distributed, tumble duration so that a particle remains stationary whilst tumbling, thus generalising the persistent random walker model. We present the exact solution for the nonequilibrium stationary state of this system in the case of two random walkers. We find this to be characterised by two lengthscales, one arising from the jamming of approaching particles, and the other from one particle moving when the other is tumbling. The first of these lengthscales vanishes in a scaling limit where the continuous-space dynamics is recovered whilst the second remains finite. Thus the nonequilibrium stationary state reveals a rich structure of attractive, jammed and extended pieces.

Interactive Videodisc Learning Systems.

ERIC Educational Resources Information Center

Currier, Richard L.

1983-01-01

Discussion of capabilities of interactive videodisc, which combines video images recorded on disc and random-access, highlights interactivity; teaching techniques with videodiscs (including masking, disassembly, movie maps, tactical maps, action code, and simulation); costs; and games. Illustrative material is provided. (High Technology, P. O. Box…

The effects of the one-step replica symmetry breaking on the Sherrington-Kirkpatrick spin glass model in the presence of random field with a joint Gaussian probability density function for the exchange interactions and random fields

NASA Astrophysics Data System (ADS)

Hadjiagapiou, Ioannis A.; Velonakis, Ioannis N.

2018-07-01

The Sherrington-Kirkpatrick Ising spin glass model, in the presence of a random magnetic field, is investigated within the framework of the one-step replica symmetry breaking. The two random variables (exchange integral interaction Jij and random magnetic field hi) are drawn from a joint Gaussian probability density function characterized by a correlation coefficient ρ, assuming positive and negative values. The thermodynamic properties, the three different phase diagrams and system's parameters are computed with respect to the natural parameters of the joint Gaussian probability density function at non-zero and zero temperatures. The low temperature negative entropy controversy, a result of the replica symmetry approach, has been partly remedied in the current study, leading to a less negative result. In addition, the present system possesses two successive spin glass phase transitions with characteristic temperatures.

Systematic and random variations in digital Thematic Mapper data

NASA Technical Reports Server (NTRS)

Duggin, M. J. (Principal Investigator); Sakhavat, H.

1985-01-01

Radiance recorded by any remote sensing instrument will contain noise which will consist of both systematic and random variations. Systematic variations may be due to sun-target-sensor geometry, atmospheric conditions, and the interaction of the spectral characteristics of the sensor with those of upwelling radiance. Random variations in the data may be caused by variations in the nature and in the heterogeneity of the ground cover, by variations in atmospheric transmission, and by the interaction of these variations with the sensing device. It is important to be aware of the extent of random and systematic errors in recorded radiance data across ostensibly uniform ground areas in order to assess the impact on quantative image analysis procedures for both the single date and the multidate cases. It is the intention here to examine the systematic and the random variations in digital radiance data recorded in each band by the thematic mapper over crop areas which are ostensibly uniform and which are free from visible cloud.

Physical interrelation between Fokker-Planck and random walk models with application to Coulomb interactions.

NASA Technical Reports Server (NTRS)

Englert, G. W.

1971-01-01

A model of the random walk is formulated to allow a simple computing procedure to replace the difficult problem of solution of the Fokker-Planck equation. The step sizes and probabilities of taking steps in the various directions are expressed in terms of Fokker-Planck coefficients. Application is made to many particle systems with Coulomb interactions. The relaxation of a highly peaked velocity distribution of particles to equilibrium conditions is illustrated.

Collective states in social systems with interacting learning agents

NASA Astrophysics Data System (ADS)

Semeshenko, Viktoriya; Gordon, Mirta B.; Nadal, Jean-Pierre

2008-08-01

We study the implications of social interactions and individual learning features on consumer demand in a simple market model. We consider a social system of interacting heterogeneous agents with learning abilities. Given a fixed price, agents repeatedly decide whether or not to buy a unit of a good, so as to maximize their expected utilities. This model is close to Random Field Ising Models, where the random field corresponds to the idiosyncratic willingness to pay. We show that the equilibrium reached depends on the nature of the information agents use to estimate their expected utilities. It may be different from the systems’ Nash equilibria.

Parent-child interactions during traditional and interactive media settings: A pilot randomized control study.

PubMed

Skaug, Silje; Englund, Kjellrun T; Saksvik-Lehouillier, Ingvild; Lydersen, Stian; Wichstrøm, Lars

2018-04-01

Parent-child interactions are pivotal for children's socioemotional development, yet might suffer with increased attention to screen media, as research has suggested. In response, we hypothesized that parent-child play on a tablet computer, as representative of interactive media, would generate higher-quality parent-child interactions than toy play or watching TV. We examined the emotional availability of mothers and their 2-year-old child during the previous three contexts using a randomized crossover design (n = 22) in a laboratory room. Among other results, mothers were more sensitive and structuring during joint gaming on a tablet than when engaged in toy play or watching TV. In addition, mothers were more hostile toward their children during play with traditional toys than during joint tablet gaming and television co-viewing. Such findings provide new insights into the impact of new media on parent-child interactions, chiefly by demonstrating that interactive media devices such as tablets can afford growth-enhancing parent-child interactions. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Ising lattices with +/-J second-nearest-neighbor interactions

NASA Astrophysics Data System (ADS)

Ramírez-Pastor, A. J.; Nieto, F.; Vogel, E. E.

1997-06-01

Second-nearest-neighbor interactions are added to the usual nearest-neighbor Ising Hamiltonian for square lattices in different ways. The starting point is a square lattice where half the nearest-neighbor interactions are ferromagnetic and the other half of the bonds are antiferromagnetic. Then, second-nearest-neighbor interactions can also be assigned randomly or in a variety of causal manners determined by the nearest-neighbor interactions. In the present paper we consider three causal and three random ways of assigning second-nearest-neighbor exchange interactions. Several ground-state properties are then calculated for each of these lattices:energy per bond ɛg, site correlation parameter pg, maximal magnetization μg, and fraction of unfrustrated bonds hg. A set of 500 samples is considered for each size N (number of spins) and array (way of distributing the N spins). The properties of the original lattices with only nearest-neighbor interactions are already known, which allows realizing the effect of the additional interactions. We also include cubic lattices to discuss the distinction between coordination number and dimensionality. Comparison with results for triangular and honeycomb lattices is done at specific points.

The role of genetic variation across IL-1β, IL-2, IL-6, and BDNF in antipsychotic-induced weight gain.

PubMed

Fonseka, Trehani M; Tiwari, Arun K; Gonçalves, Vanessa F; Lieberman, Jeffrey A; Meltzer, Herbert Y; Goldstein, Benjamin I; Kennedy, James L; Kennedy, Sidney H; Müller, Daniel J

2015-01-01

Antipsychotics with high weight gain-inducing propensities influence the expression of immune and neurotrophin genes, which have been independently related to obesity indices. Thus, we investigated whether variants in the genes encoding interleukin (IL)-1β, IL-2, and IL-6 and brain-derived neurotrophic factor (BDNF) Val66Met are associated with antipsychotic-induced weight gain (AIWG). Nineteen polymorphisms were genotyped using Taqman(®) assays in 188 schizophrenia patients on antipsychotic treatment for up to 14 weeks. Mean weight change (%) from baseline was compared across genotypic groups using analysis of covariance (ANCOVA). Epistatic effects between cytokine polymorphisms and BDNF Val66Met were tested using Model-Based Multifactor Dimensionality Reduction. In European patients, IL-1β rs16944*GA (P = 0.013, Pcorrected = 0.182), IL-1β rs1143634*G (P = 0.001, Pcorrected = 0.014), and BDNF Val66Met (Val/Val, P = 0.004, Pcorrected = 0.056) were associated with greater AIWG, as were IL-1β rs4849127*A (P = 0.049, Pcorrected = 0.784), and IL-1β rs16944*GA (P = 0.012, Pcorrected = 0.192) in African Americans. BDNF Val66Met interacted with both IL-1β rs13032029 (Val/Met+ TT, PPerm = 0.029), and IL-6 rs2069837 (Val/Val+ AA, PPerm = 0.021) in Europeans, in addition to IL-1β rs16944 (Val/Val+ GA, PPerm = 0.006) in African Americans. SNPs across IL-1β and BDNF Val66Met may influence AIWG. Replication of these findings in larger, independent samples is warranted.

Influence of evolution on the stability of ecological communities.

PubMed

Loeuille, Nicolas

2010-12-01

In randomly assembled communities, diversity is known to have a destabilizing effect. Evolution may affect this result, but our theoretical knowledge of its role is mostly limited to models of small food webs. In the present article, I introduce evolution in a two-species Lotka-Volterra model in which I vary the interaction type and the cost constraining evolution. Regardless of the cost type, evolution tends to stabilize the dynamics more often in trophic interactions than for mutualism or competition. I then use simulations to study the effect of evolution in larger communities that contain all interaction types. Results suggest that evolution usually stabilizes the dynamics. This stabilizing effect is stronger when evolution affects trophic interactions, but happens for all interaction types. Stabilization decreases with diversity and evolution becomes destabilizing in very diverse communities. This suggests that evolution may not counteract the destabilizing effect of diversity observed in random communities. © 2010 Blackwell Publishing Ltd/CNRS.

Sonic boom interaction with turbulence

NASA Technical Reports Server (NTRS)

Rusak, Zvi; Giddings, Thomas E.

1994-01-01

A recently developed transonic small-disturbance model is used to analyze the interactions of random disturbances with a weak shock. The model equation has an extended form of the classic small-disturbance equation for unsteady transonic aerodynamics. It shows that diffraction effects, nonlinear steepening effects, focusing and caustic effects and random induced vorticity fluctuations interact simultaneously to determine the development of the shock wave in space and time and the pressure field behind it. A finite-difference algorithm to solve the mixed-type elliptic hyperbolic flows around the shock wave is presented. Numerical calculations of shock wave interactions with various deterministic vorticity and temperature disturbances result in complicate shock wave structures and describe peaked as well as rounded pressure signatures behind the shock front, as were recorded in experiments of sonic booms running through atmospheric turbulence.

Density and energy relaxation in an open one-dimensional system

NASA Astrophysics Data System (ADS)

Jose, Prasanth P.; Bagchi, Biman

2004-05-01

A new master equation to mimic the dynamics of a collection of interacting random walkers in an open system is proposed and solved numerically. In this model, the random walkers interact through excluded volume interaction (single-file system); and the total number of walkers in the lattice can fluctuate because of exchange with a bath. In addition, the movement of the random walkers is biased by an external perturbation. Two models for the latter are considered: (1) an inverse potential (V∝1/r), where r is the distance between the center of the perturbation and the random walker and (2) an inverse of sixth power potential (V∝1/r6). The calculated density of the walkers and the total energy show interesting dynamics. When the size of the system is comparable to the range of the perturbing field, the energy relaxation is found to be highly nonexponential. In this range, the system can show stretched exponential (e-(t/τs)β) and even logarithmic time dependence of energy relaxation over a limited range of time. Introduction of density exchange in the lattice markedly weakens this nonexponentiality of the relaxation function, irrespective of the nature of perturbation.

A random walk model to evaluate autism

NASA Astrophysics Data System (ADS)

Moura, T. R. S.; Fulco, U. L.; Albuquerque, E. L.

2018-02-01

A common test administered during neurological examination in children is the analysis of their social communication and interaction across multiple contexts, including repetitive patterns of behavior. Poor performance may be associated with neurological conditions characterized by impairments in executive function, such as the so-called pervasive developmental disorders (PDDs), a particular condition of the autism spectrum disorders (ASDs). Inspired in these diagnosis tools, mainly those related to repetitive movements and behaviors, we studied here how the diffusion regimes of two discrete-time random walkers, mimicking the lack of social interaction and restricted interests developed for children with PDDs, are affected. Our model, which is based on the so-called elephant random walk (ERW) approach, consider that one of the random walker can learn and imitate the microscopic behavior of the other with probability f (1 - f otherwise). The diffusion regimes, measured by the Hurst exponent (H), is then obtained, whose changes may indicate a different degree of autism.

Phase diagram for the Kuramoto model with van Hemmen interactions.

PubMed

Kloumann, Isabel M; Lizarraga, Ian M; Strogatz, Steven H

2014-01-01

We consider a Kuramoto model of coupled oscillators that includes quenched random interactions of the type used by van Hemmen in his model of spin glasses. The phase diagram is obtained analytically for the case of zero noise and a Lorentzian distribution of the oscillators' natural frequencies. Depending on the size of the attractive and random coupling terms, the system displays four states: complete incoherence, partial synchronization, partial antiphase synchronization, and a mix of antiphase and ordinary synchronization.

Superfluid-insulator transition in a disordered two-dimensional quantum rotor model with random on-site interactions

NASA Astrophysics Data System (ADS)

An, Taeyang; Cha, Min-Chul

2013-03-01

We study the superfluid-insulator quantum phase transition in a disordered two-dimensional quantum rotor model with random on-site interactions in the presence of particle-hole symmetry. Via worm-algorithm Monte Carlo calculations of superfluid density and compressibility, we find the dynamical critical exponent z ~ 1 . 13 (2) and the correlation length critical exponent 1 / ν ~ 1 . 1 (1) . These exponents suggest that the insulating phase is a incompressible Mott glass rather than a Bose glass.

Nonparametric tests for interaction and group differences in a two-way layout.

PubMed

Fisher, A C; Wallenstein, S

1991-01-01

Nonparametric tests of group differences and interaction across strata are developed in which the null hypotheses for these tests are expressed as functions of rho i = P(X > Y) + 1/2P(X = Y), where X refers to a random observation from one group and Y refers to a random observation from the other group within stratum i. The estimator r of the parameter rho is shown to be a useful way to summarize and examine data for ordinal and continuous data.

Continuous time random walk with local particle-particle interaction

NASA Astrophysics Data System (ADS)

Xu, Jianping; Jiang, Guancheng

2018-05-01

The continuous time random walk (CTRW) is often applied to the study of particle motion in disordered media. Yet most such applications do not allow for particle-particle (walker-walker) interaction. In this paper, we consider a CTRW with particle-particle interaction; however, for simplicity, we restrain the interaction to be local. The generalized Chapman-Kolmogorov equation is modified by introducing a perturbation function that fluctuates around 1, which models the effect of interaction. Subsequently, a time-fractional nonlinear advection-diffusion equation is derived from this walking system. Under the initial condition of condensed particles at the origin and the free-boundary condition, we numerically solve this equation with both attractive and repulsive particle-particle interactions. Moreover, a Monte Carlo simulation is devised to verify the results of the above numerical work. The equation and the simulation unanimously predict that this walking system converges to the conventional one in the long-time limit. However, for systems where the free-boundary condition and long-time limit are not simultaneously satisfied, this convergence does not hold.

Molecules for security measures: from keypad locks to advanced communication protocols.

PubMed

Andréasson, J; Pischel, U

2018-04-03

The idea of using molecules in the context of information security has sparked the interest of researchers from many scientific disciplines. This is clearly manifested in the diversity of the molecular platforms and the analytical techniques used for this purpose, some of which we highlight in this Tutorial Review. Moreover, those molecular systems can be used to emulate a broad spectrum of security measures. For a long time, molecular keypad locks enjoyed a clear preference and the review starts off with a description of how these devices developed. In the last few years, however, the field has evolved into something larger. Examples include more complex authentication protocols (multi-factor authentication and one-time passwords), the recognition of erroneous procedures in data transmission (parity devices), as well as steganographic and cryptographic protection.

[Risk/protective factors and prevention programs for drug dependence in Peru].

PubMed

Cabanillas-Rojas, William

2012-03-01

Risk/ protective factors (RPF) are main elements for the analysis, understanding and formulation of answers for the prevention of drug dependences. The objective of this article is to present a literature review about the RPF and their implications in the design of preventive programs. It will focus on individual (genetic aspects, early experiences and psicosocial skills), family (parental control and monitoring, permissiveness, parenting styles), peer (group pressure and social norms) and communitarian (disorganization) RPF. On the other hand, the need of incorporating a multifactor conceptual framework for the preventive approach to drug dependences, articulating the intervention spaces (school, family and community), assuming and evolving perspective allowing the implementations of sustained actions is evidenced. On top, the implications for future research and public policy formulation are discussed.

Prediction model for carbonation depth of concrete subjected to freezing-thawing cycles

NASA Astrophysics Data System (ADS)

Xiao, Qian Hui; Li, Qiang; Guan, Xiao; Xian Zou, Ying

2018-03-01

Through the indoor simulation test of the concrete durability under the coupling effect of freezing-thawing and carbonation, the variation regularity of concrete neutralization depth under freezing-thawing and carbonation was obtained. Based on concrete carbonation mechanism, the relationship between the air diffusion coefficient and porosity in concrete was analyzed and the calculation method of porosity in Portland cement concrete and fly ash cement concrete was investigated, considering the influence of the freezing-thawing damage on the concrete diffusion coefficient. Finally, a prediction model of carbonation depth of concrete under freezing-thawing circumstance was established. The results obtained using this prediction model agreed well with the experimental test results, and provided a theoretical reference and basis for the concrete durability analysis under multi-factor environments.

A Federated Digital Identity Management Approach for Business Processes

NASA Astrophysics Data System (ADS)

Bertino, Elisa; Ferrini, Rodolfo; Musci, Andrea; Paci, Federica; Steuer, Kevin J.

Business processes have gained a lot of attention because of the pressing need for integrating existing resources and services to better fulfill customer needs. A key feature of business processes is that they are built from composable services, referred to as component services, that may belong to different domains. In such a context, flexible multi-domain identity management solutions are crucial for increased security and user-convenience. In particular, it is important that during the execution of a business process the component services be able to verify the identity of the client to check that it has the required permissions for accessing the services. To address the problem of multi-domain identity management, we propose a multi-factor identity attribute verification protocol for business processes that assures clients privacy and handles naming heterogeneity.

Gender differences in erotic plasticity--evolutionary or sociocultural forces? Comment on Baumeister (2000)

PubMed

Hyde, J S; Durik, A M

2000-05-01

R. F. Baumeister (2000) argued that there are gender differences in erotic plasticity, meaning that women are more influenced by cultural and social factors than men are. He attributed the gender difference in erotic plasticity to evolutionary, biological forces. We propose an alternative account of the data using a multifactor sociocultural model that rests on 4 assertions: (a) Men have more power than women on many levels including the institutional and the interpersonal levels, (b) education increases women's power, (c) groups with less power (women) pay more attention to and adapt their behavior more to the group with more power (men) than the reverse, and (d) gender roles powerfully shape behavior, and heterosexuality is a more important element of the male role than the female role.

Group Random Call Can Positively Affect Student In-Class Clicker Discussions.

PubMed

Knight, Jennifer K; Wise, Sarah B; Sieke, Scott

2016-01-01

Understanding how instructional techniques and classroom norms influence in-class student interactions has the potential to positively impact student learning. Many previous studies have shown that students benefit from discussing their ideas with one another in class. In this study of introductory biology students, we explored how using an in-class accountability system might affect the nature of clicker-question discussions. Clicker-question discussions in which student groups were asked to report their ideas voluntarily (volunteer call) were compared with discussions in which student groups were randomly selected to report their ideas (random call). We hypothesized that the higher-accountability condition (random call) would impress upon students the importance of their discussions and thus positively influence how they interacted. Our results suggest that a higher proportion of discussions in the random call condition contained exchanges of reasoning, some forms of questioning, and both on- and off-topic comments compared with discussion in the volunteer call condition. Although group random call does not impact student performance on clicker questions, the positive impact of this instructional approach on exchanges of reasoning and other features suggests it may encourage some types of student interactions that support learning. © 2016 J. K. Knight et al. CBE—Life Sciences Education © 2016 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Understanding and comparisons of different sampling approaches for the Fourier Amplitudes Sensitivity Test (FAST)

PubMed Central

Xu, Chonggang; Gertner, George

2013-01-01

Fourier Amplitude Sensitivity Test (FAST) is one of the most popular uncertainty and sensitivity analysis techniques. It uses a periodic sampling approach and a Fourier transformation to decompose the variance of a model output into partial variances contributed by different model parameters. Until now, the FAST analysis is mainly confined to the estimation of partial variances contributed by the main effects of model parameters, but does not allow for those contributed by specific interactions among parameters. In this paper, we theoretically show that FAST analysis can be used to estimate partial variances contributed by both main effects and interaction effects of model parameters using different sampling approaches (i.e., traditional search-curve based sampling, simple random sampling and random balance design sampling). We also analytically calculate the potential errors and biases in the estimation of partial variances. Hypothesis tests are constructed to reduce the effect of sampling errors on the estimation of partial variances. Our results show that compared to simple random sampling and random balance design sampling, sensitivity indices (ratios of partial variances to variance of a specific model output) estimated by search-curve based sampling generally have higher precision but larger underestimations. Compared to simple random sampling, random balance design sampling generally provides higher estimation precision for partial variances contributed by the main effects of parameters. The theoretical derivation of partial variances contributed by higher-order interactions and the calculation of their corresponding estimation errors in different sampling schemes can help us better understand the FAST method and provide a fundamental basis for FAST applications and further improvements. PMID:24143037

Understanding and comparisons of different sampling approaches for the Fourier Amplitudes Sensitivity Test (FAST).

PubMed

Xu, Chonggang; Gertner, George

2011-01-01

Fourier Amplitude Sensitivity Test (FAST) is one of the most popular uncertainty and sensitivity analysis techniques. It uses a periodic sampling approach and a Fourier transformation to decompose the variance of a model output into partial variances contributed by different model parameters. Until now, the FAST analysis is mainly confined to the estimation of partial variances contributed by the main effects of model parameters, but does not allow for those contributed by specific interactions among parameters. In this paper, we theoretically show that FAST analysis can be used to estimate partial variances contributed by both main effects and interaction effects of model parameters using different sampling approaches (i.e., traditional search-curve based sampling, simple random sampling and random balance design sampling). We also analytically calculate the potential errors and biases in the estimation of partial variances. Hypothesis tests are constructed to reduce the effect of sampling errors on the estimation of partial variances. Our results show that compared to simple random sampling and random balance design sampling, sensitivity indices (ratios of partial variances to variance of a specific model output) estimated by search-curve based sampling generally have higher precision but larger underestimations. Compared to simple random sampling, random balance design sampling generally provides higher estimation precision for partial variances contributed by the main effects of parameters. The theoretical derivation of partial variances contributed by higher-order interactions and the calculation of their corresponding estimation errors in different sampling schemes can help us better understand the FAST method and provide a fundamental basis for FAST applications and further improvements.

Multi-agent coordination in directed moving neighbourhood random networks

NASA Astrophysics Data System (ADS)

Shang, Yi-Lun

2010-07-01

This paper considers the consensus problem of dynamical multiple agents that communicate via a directed moving neighbourhood random network. Each agent performs random walk on a weighted directed network. Agents interact with each other through random unidirectional information flow when they coincide in the underlying network at a given instant. For such a framework, we present sufficient conditions for almost sure asymptotic consensus. Numerical examples are taken to show the effectiveness of the obtained results.

Random vibration analysis of train-bridge under track irregularities and traveling seismic waves using train-slab track-bridge interaction model

NASA Astrophysics Data System (ADS)

Zeng, Zhi-Ping; Zhao, Yan-Gang; Xu, Wen-Tao; Yu, Zhi-Wu; Chen, Ling-Kun; Lou, Ping

2015-04-01

The frequent use of bridges in high-speed railway lines greatly increases the probability that trains are running on bridges when earthquakes occur. This paper investigates the random vibrations of a high-speed train traversing a slab track on a continuous girder bridge subjected to track irregularities and traveling seismic waves by the pseudo-excitation method (PEM). To derive the equations of motion of the train-slab track-bridge interaction system, the multibody dynamics and finite element method models are used for the train and the track and bridge, respectively. By assuming track irregularities to be fully coherent random excitations with time lags between different wheels and seismic accelerations to be uniformly modulated, non-stationary random excitations with time lags between different foundations, the random load vectors of the equations of motion are transformed into a series of deterministic pseudo-excitations based on PEM and the wheel-rail contact relationship. A computer code is developed to obtain the time-dependent random responses of the entire system. As a case study, the random vibration characteristics of an ICE-3 high-speed train traversing a seven-span continuous girder bridge simultaneously excited by track irregularities and traveling seismic waves are analyzed. The influence of train speed and seismic wave propagation velocity on the random vibration characteristics of the bridge and train are discussed.

Nonlinear complexity of random visibility graph and Lempel-Ziv on multitype range-intensity interacting financial dynamics

NASA Astrophysics Data System (ADS)

Zhang, Yali; Wang, Jun

2017-09-01

In an attempt to investigate the nonlinear complex evolution of financial dynamics, a new financial price model - the multitype range-intensity contact (MRIC) financial model, is developed based on the multitype range-intensity interacting contact system, in which the interaction and transmission of different types of investment attitudes in a stock market are simulated by viruses spreading. Two new random visibility graph (VG) based analyses and Lempel-Ziv complexity (LZC) are applied to study the complex behaviors of return time series and the corresponding random sorted series. The VG method is the complex network theory, and the LZC is a non-parametric measure of complexity reflecting the rate of new pattern generation of a series. In this work, the real stock market indices are considered to be comparatively studied with the simulation data of the proposed model. Further, the numerical empirical study shows the similar complexity behaviors between the model and the real markets, the research confirms that the financial model is reasonable to some extent.

Peer Influence, Genetic Propensity, and Binge Drinking: A Natural Experiment and a Replication.

PubMed

Guo, Guang; Li, Yi; Wang, Hongyu; Cai, Tianji; Duncan, Greg J

2015-11-01

The authors draw data from the College Roommate Study (ROOM) and the National Longitudinal Study of Adolescent Health to investigate gene-environment interaction effects on youth binge drinking. In ROOM, the environmental influence was measured by the precollege drinking behavior of randomly assigned roommates. Random assignment safeguards against friend selection and removes the threat of gene-environment correlation that makes gene-environment interaction effects difficult to interpret. On average, being randomly assigned a drinking peer as opposed to a nondrinking peer increased college binge drinking by 0.5-1.0 episodes per month, or 20%-40% the average amount of binge drinking. However, this peer influence was found only among youths with a medium level of genetic propensity for alcohol use; those with either a low or high genetic propensity were not influenced by peer drinking. A replication of the findings is provided in data drawn from Add Health. The study shows that gene-environment interaction analysis can uncover social-contextual effects likely to be missed by traditional sociological approaches.

An improved exceedance theory for combined random stresses

NASA Technical Reports Server (NTRS)

Lester, H. C.

1974-01-01

An extension is presented of Rice's classic solution for the exceedances of a constant level by a single random process to its counterpart for an n-dimensional vector process. An interaction boundary, analogous to the constant level considered by Rice for the one-dimensional case, is assumed in the form of a hypersurface. The theory for the numbers of boundary exceedances is developed by using a joint statistical approach which fully accounts for all cross-correlation effects. An exact expression is derived for the n-dimensional exceedance density function, which is valid for an arbitrary interaction boundary. For application to biaxial states of combined random stress, the general theory is reduced to the two-dimensional case. An elliptical stress interaction boundary is assumed and the exact expression for the density function is presented. The equations are expressed in a format which facilitates calculating the exceedances by numerically evaluating a line integral. The behavior of the density function for the two-dimensional case is briefly discussed.

How Fast Can Networks Synchronize? A Random Matrix Theory Approach

NASA Astrophysics Data System (ADS)

Timme, Marc; Wolf, Fred; Geisel, Theo

2004-03-01

Pulse-coupled oscillators constitute a paradigmatic class of dynamical systems interacting on networks because they model a variety of biological systems including flashing fireflies and chirping crickets as well as pacemaker cells of the heart and neural networks. Synchronization is one of the most simple and most prevailing kinds of collective dynamics on such networks. Here we study collective synchronization [1] of pulse-coupled oscillators interacting on asymmetric random networks. Using random matrix theory we analytically determine the speed of synchronization in such networks in dependence on the dynamical and network parameters [2]. The speed of synchronization increases with increasing coupling strengths. Surprisingly, however, it stays finite even for infinitely strong interactions. The results indicate that the speed of synchronization is limited by the connectivity of the network. We discuss the relevance of our findings to general equilibration processes on complex networks. [5mm] [1] M. Timme, F. Wolf, T. Geisel, Phys. Rev. Lett. 89:258701 (2002). [2] M. Timme, F. Wolf, T. Geisel, cond-mat/0306512 (2003).

Generic dynamical features of quenched interacting quantum systems: Survival probability, density imbalance, and out-of-time-ordered correlator

NASA Astrophysics Data System (ADS)

Torres-Herrera, E. J.; García-García, Antonio M.; Santos, Lea F.

2018-02-01

We study numerically and analytically the quench dynamics of isolated many-body quantum systems. Using full random matrices from the Gaussian orthogonal ensemble, we obtain analytical expressions for the evolution of the survival probability, density imbalance, and out-of-time-ordered correlator. They are compared with numerical results for a one-dimensional-disordered model with two-body interactions and shown to bound the decay rate of this realistic system. Power-law decays are seen at intermediate times, and dips below the infinite time averages (correlation holes) occur at long times for all three quantities when the system exhibits level repulsion. The fact that these features are shared by both the random matrix and the realistic disordered model indicates that they are generic to nonintegrable interacting quantum systems out of equilibrium. Assisted by the random matrix analytical results, we propose expressions that describe extremely well the dynamics of the realistic chaotic system at different time scales.

Transport behaviors of locally fractional coupled Brownian motors with fluctuating interactions

NASA Astrophysics Data System (ADS)

Wang, Huiqi; Ni, Feixiang; Lin, Lifeng; Lv, Wangyong; Zhu, Hongqiang

2018-09-01

In some complex viscoelastic mediums, it is ubiquitous that absorbing and desorbing surrounding Brownian particles randomly occur in coupled systems. The conventional method is to model a variable-mass system driven by both multiplicative and additive noises. In this paper, an improved mathematical model is created based on generalized Langevin equations (GLE) to characterize the random interaction with locally fluctuating number of coupled particles in the elastically coupled factional Brownian motors (FBM). By the numerical simulations, the effect of fluctuating interactions on collective transport behaviors is investigated, and some abnormal phenomena, such as cooperative behaviors, stochastic resonance (SR) and anomalous transport, are observed in the regime of sub-diffusion.

Micromagnetism in a planar system with a random magnetic anisotropy and two-dimensional magnetic correlations

NASA Astrophysics Data System (ADS)

Komogortsev, S. V.; Fel'k, V. A.; Iskhakov, R. S.; Shadrina, G. V.

2017-08-01

The hysteresis loops and the micromagnetic structure of a ferromagnetic nanolayer with a randomly oriented local easy magnetization axis and two-dimensional magnetization correlations are studied using a micromagnetic simulation. The properties and the micromagnetic structure of the nanolayer are determined by the competition between the anisotropy and exchange energies and by the dipole-dipole interaction energy. The magnetic microstructure can be described as an ensemble of stochastic magnetic domains and topological magnetization defects. Dipole-dipole interaction suppresses the formation of topological magnetization defects. The topological defects in the magnetic microstructure can cause a sharper change in the coercive force with the crystallite size than that predicted by the random magnetic anisotropy model.

Knowledge diffusion of dynamical network in terms of interaction frequency.

PubMed

Liu, Jian-Guo; Zhou, Qing; Guo, Qiang; Yang, Zhen-Hua; Xie, Fei; Han, Jing-Ti

2017-09-07

In this paper, we present a knowledge diffusion (SKD) model for dynamic networks by taking into account the interaction frequency which always used to measure the social closeness. A set of agents, which are initially interconnected to form a random network, either exchange knowledge with their neighbors or move toward a new location through an edge-rewiring procedure. The activity of knowledge exchange between agents is determined by a knowledge transfer rule that the target node would preferentially select one neighbor node to transfer knowledge with probability p according to their interaction frequency instead of the knowledge distance, otherwise, the target node would build a new link with its second-order neighbor preferentially or select one node in the system randomly with probability 1 - p. The simulation results show that, comparing with the Null model defined by the random selection mechanism and the traditional knowledge diffusion (TKD) model driven by knowledge distance, the knowledge would spread more fast based on SKD driven by interaction frequency. In particular, the network structure of SKD would evolve as an assortative one, which is a fundamental feature of social networks. This work would be helpful for deeply understanding the coevolution of the knowledge diffusion and network structure.

Unraveling spurious properties of interaction networks with tailored random networks.

PubMed

Bialonski, Stephan; Wendler, Martin; Lehnertz, Klaus

2011-01-01

We investigate interaction networks that we derive from multivariate time series with methods frequently employed in diverse scientific fields such as biology, quantitative finance, physics, earth and climate sciences, and the neurosciences. Mimicking experimental situations, we generate time series with finite length and varying frequency content but from independent stochastic processes. Using the correlation coefficient and the maximum cross-correlation, we estimate interdependencies between these time series. With clustering coefficient and average shortest path length, we observe unweighted interaction networks, derived via thresholding the values of interdependence, to possess non-trivial topologies as compared to Erdös-Rényi networks, which would indicate small-world characteristics. These topologies reflect the mostly unavoidable finiteness of the data, which limits the reliability of typically used estimators of signal interdependence. We propose random networks that are tailored to the way interaction networks are derived from empirical data. Through an exemplary investigation of multichannel electroencephalographic recordings of epileptic seizures--known for their complex spatial and temporal dynamics--we show that such random networks help to distinguish network properties of interdependence structures related to seizure dynamics from those spuriously induced by the applied methods of analysis.

Unraveling Spurious Properties of Interaction Networks with Tailored Random Networks

PubMed Central

Bialonski, Stephan; Wendler, Martin; Lehnertz, Klaus

2011-01-01

We investigate interaction networks that we derive from multivariate time series with methods frequently employed in diverse scientific fields such as biology, quantitative finance, physics, earth and climate sciences, and the neurosciences. Mimicking experimental situations, we generate time series with finite length and varying frequency content but from independent stochastic processes. Using the correlation coefficient and the maximum cross-correlation, we estimate interdependencies between these time series. With clustering coefficient and average shortest path length, we observe unweighted interaction networks, derived via thresholding the values of interdependence, to possess non-trivial topologies as compared to Erdös-Rényi networks, which would indicate small-world characteristics. These topologies reflect the mostly unavoidable finiteness of the data, which limits the reliability of typically used estimators of signal interdependence. We propose random networks that are tailored to the way interaction networks are derived from empirical data. Through an exemplary investigation of multichannel electroencephalographic recordings of epileptic seizures – known for their complex spatial and temporal dynamics – we show that such random networks help to distinguish network properties of interdependence structures related to seizure dynamics from those spuriously induced by the applied methods of analysis. PMID:21850239

Psychosocial effects of a skin camouflage program in female survivors with head and neck cancer: A randomized controlled trial.

PubMed

Chen, Shu-Ching; Huang, Bing-Shen; Lin, Chien-Yu; Fan, Kang-Hsing; Chang, Joseph Tung-Chien; Wu, Shu-Chen; Lai, Yeur-Hur

2017-09-01

The purpose of this study was to evaluate the effects of a skin camouflage program on disfigurement, self-esteem, social interaction, and body image in female head and neck cancer (HNC) survivors. A prospective, repeated-measures, randomized controlled therapeutic intervention design was used. A total of 66 participants were randomly assigned to each group, with 32 in the experimental group and 34 in the control group. The experimental group received a 4-session skin camouflage program, and the control group received routine care. Patients were assessed at 3 time points: baseline assessment (T0) and then at 1, 2, and 3 months (T1, T2, and T3, respectively) after participating in the skin camouflage program. Patients in the experimental group had significantly less facial disfigurement, depression, fear of social interaction, and anxiety regarding social interaction compared with those in the control group. Participants in both groups had significantly lower levels of facial disfigurement, depression, fear of social interaction, anxiety of social interaction, and body image at the final posttest assessment than at the pretest assessment. There were no differences between the groups and within groups with respect to self-esteem. The 3-month skin camouflage program effectively improved facial disfigurement, fear of social interaction, anxiety of social interaction, and body image of female HNC survivors. A survival care plan should include a skin camouflage program to improve body image perception and decrease anxiety after treatment of HNC. Copyright © 2016 John Wiley & Sons, Ltd.

Interaction between the FTO gene, body mass index and depression: meta-analysis of 13701 individuals†

PubMed Central

Rivera, Margarita; Locke, Adam E.; Corre, Tanguy; Czamara, Darina; Wolf, Christiane; Ching-Lopez, Ana; Milaneschi, Yuri; Kloiber, Stefan; Cohen-Woods, Sara; Rucker, James; Aitchison, Katherine J.; Bergmann, Sven; Boomsma, Dorret I.; Craddock, Nick; Gill, Michael; Holsboer, Florian; Hottenga, Jouke-Jan; Korszun, Ania; Kutalik, Zoltan; Lucae, Susanne; Maier, Wolfgang; Mors, Ole; Müller-Myhsok, Bertram; Owen, Michael J.; Penninx, Brenda W. J. H.; Preisig, Martin; Rice, John; Rietschel, Marcella; Tozzi, Federica; Uher, Rudolf; Vollenweider, Peter; Waeber, Gerard; Willemsen, Gonneke; Craig, Ian W.; Farmer, Anne E.; Lewis, Cathryn M.; Breen, Gerome; McGuffin, Peter

2017-01-01

Background Depression and obesity are highly prevalent, and major impacts on public health frequently co-occur. Recently, we reported that having depression moderates the effect of the FTO gene, suggesting its implication in the association between depression and obesity. Aims To confirm these findings by investigating the FTO polymorphism rs9939609 in new cohorts, and subsequently in a meta-analysis. Method The sample consists of 6902 individuals with depression and 6799 controls from three replication cohorts and two original discovery cohorts. Linear regression models were performed to test for association between rs9939609 and body mass index (BMI), and for the interaction between rs9939609 and depression status for an effect on BMI. Fixed and random effects meta-analyses were performed using METASOFT. Results In the replication cohorts, we observed a significant interaction between FTO, BMI and depression with fixed effects meta-analysis (β = 0.12, P = 2.7 × 10−4) and with the Han/Eskin random effects method (P = 1.4 × 10−7) but not with traditional random effects (β = 0.1, P = 0.35). When combined with the discovery cohorts, random effects meta-analysis also supports the interaction (β = 0.12, P = 0.027) being highly significant based on the Han/Eskin model (P = 6.9 × 10−8). On average, carriers of the risk allele who have depression have a 2.2% higher BMI for each risk allele, over and above the main effect of FTO. Conclusions This meta-analysis provides additional support for a significant interaction between FTO, depression and BMI, indicating that depression increases the effect of FTO on BMI. The findings provide a useful starting point in understanding the biological mechanism involved in the association between obesity and depression. PMID:28642257

Predicting attention-deficit/hyperactivity disorder severity from psychosocial stress and stress-response genes: a random forest regression approach

PubMed Central

van der Meer, D; Hoekstra, P J; van Donkelaar, M; Bralten, J; Oosterlaan, J; Heslenfeld, D; Faraone, S V; Franke, B; Buitelaar, J K; Hartman, C A

2017-01-01

Identifying genetic variants contributing to attention-deficit/hyperactivity disorder (ADHD) is complicated by the involvement of numerous common genetic variants with small effects, interacting with each other as well as with environmental factors, such as stress exposure. Random forest regression is well suited to explore this complexity, as it allows for the analysis of many predictors simultaneously, taking into account any higher-order interactions among them. Using random forest regression, we predicted ADHD severity, measured by Conners’ Parent Rating Scales, from 686 adolescents and young adults (of which 281 were diagnosed with ADHD). The analysis included 17 374 single-nucleotide polymorphisms (SNPs) across 29 genes previously linked to hypothalamic–pituitary–adrenal (HPA) axis activity, together with information on exposure to 24 individual long-term difficulties or stressful life events. The model explained 12.5% of variance in ADHD severity. The most important SNP, which also showed the strongest interaction with stress exposure, was located in a region regulating the expression of telomerase reverse transcriptase (TERT). Other high-ranking SNPs were found in or near NPSR1, ESR1, GABRA6, PER3, NR3C2 and DRD4. Chronic stressors were more influential than single, severe, life events. Top hits were partly shared with conduct problems. We conclude that random forest regression may be used to investigate how multiple genetic and environmental factors jointly contribute to ADHD. It is able to implicate novel SNPs of interest, interacting with stress exposure, and may explain inconsistent findings in ADHD genetics. This exploratory approach may be best combined with more hypothesis-driven research; top predictors and their interactions with one another should be replicated in independent samples. PMID:28585928

Changes in Brain Volume and Cognition in a Randomized Trial of Exercise and Social Interaction in a Community-Based Sample of Non-Demented Chinese Elders

PubMed Central

Mortimer, James A.; Ding, Ding; Borenstein, Amy R.; DeCarli, Charles; Guo, Qihao; Wu, Yougui; Zhao, Qianhua; Chu, Shugang

2013-01-01

Physical exercise has been shown to increase brain volume and improve cognition in randomized trials of non-demented elderly. Although greater social engagement was found to reduce dementia risk in observational studies, randomized trials of social interventions have not been reported. A representative sample of 120 elderly from Shanghai, China was randomized to four groups (Tai Chi, Walking, Social Interaction, No Intervention) for 40 weeks. Two MRIs were obtained, one before the intervention period, the other after. A neuropsychological battery was administered at baseline, 20 weeks, and 40 weeks. Comparison of changes in brain volumes in intervention groups with the No Intervention group were assessed by t-tests. Time-intervention group interactions for neuropsychological measures were evaluated with repeated-measures mixed models. Compared to the No Intervention group, significant increases in brain volume were seen in the Tai Chi and Social Intervention groups (p < 0.05). Improvements also were observed in several neuropsychological measures in the Tai Chi group, including the Mattis Dementia Rating Scale score (p = 0.004), the Trailmaking Test A (p = 0.002) and B (p = 0.0002), the Auditory Verbal Learning Test (p = 0.009), and verbal fluency for animals (p = 0.01). The Social Interaction group showed improvement on some, but fewer neuropsychological indices. No differences were observed between the Walking and No Intervention groups. The findings differ from previous clinical trials in showing increases in brain volume and improvements in cognition with a largely non-aerobic exercise (Tai Chi). In addition, intellectual stimulation through social interaction was associated with increases in brain volume as well as with some cognitive improvements. PMID:22451320

Influence of Gestational Age at Initiation of Antihypertensive Therapy: Secondary Analysis of CHIPS Trial Data (Control of Hypertension in Pregnancy Study).

PubMed

Pels, Anouk; Mol, Ben Willem J; Singer, Joel; Lee, Terry; von Dadelszen, Peter; Ganzevoort, Wessel; Asztalos, Elizabeth; Magee, Laura A

2018-06-01

For hypertensive women in CHIPS (Control of Hypertension in Pregnancy Study), we assessed whether the maternal benefits of tight control could be achieved, while minimizing any potentially negative effect on fetal growth, by delaying initiation of antihypertensive therapy until later in pregnancy. For the 981 women with nonsevere, chronic or gestational hypertension randomized to less-tight (target diastolic blood pressure, 100 mm Hg), or tight (target, 85 mm Hg) control, we used mixed-effects logistic regression to examine whether the effect of less-tight (versus tight) control on major outcomes was dependent on gestational age at randomization, adjusting for baseline factors as in the primary analysis and including an interaction term between gestational age at randomization and treatment allocation. Gestational age was considered categorically (quartiles) and continuously (linear or quadratic form), and the optimal functional form selected to provide the best fit to the data based on the Akaike information criterion. Randomization before (but not after) 24 weeks to less-tight (versus tight) control was associated with fewer babies with birth weight <10th centile ( P interaction =0.005), but more preterm birth ( P interaction =0.043), and no effect on perinatal death or high-level neonatal care >48 hours ( P interaction =0.354). For the mother, less-tight (versus tight) control was associated with more severe hypertension at all gestational ages but particularly so before 28 weeks ( P interaction =0.076). In women with nonsevere, chronic, or gestational hypertension, there seems to be no gestational age at which less-tight (versus tight) control is the preferred management strategy to optimize maternal or perinatal outcomes. URL: https://www.isrctn.com. Unique identifier: ISRCTN71416914. © 2018 The Authors.

Changes in brain volume and cognition in a randomized trial of exercise and social interaction in a community-based sample of non-demented Chinese elders.

PubMed

Mortimer, James A; Ding, Ding; Borenstein, Amy R; DeCarli, Charles; Guo, Qihao; Wu, Yougui; Zhao, Qianhua; Chu, Shugang

2012-01-01

Physical exercise has been shown to increase brain volume and improve cognition in randomized trials of non-demented elderly. Although greater social engagement was found to reduce dementia risk in observational studies, randomized trials of social interventions have not been reported. A representative sample of 120 elderly from Shanghai, China was randomized to four groups (Tai Chi, Walking, Social Interaction, No Intervention) for 40 weeks. Two MRIs were obtained, one before the intervention period, the other after. A neuropsychological battery was administered at baseline, 20 weeks, and 40 weeks. Comparison of changes in brain volumes in intervention groups with the No Intervention group were assessed by t-tests. Time-intervention group interactions for neuropsychological measures were evaluated with repeated-measures mixed models. Compared to the No Intervention group, significant increases in brain volume were seen in the Tai Chi and Social Intervention groups (p < 0.05). Improvements also were observed in several neuropsychological measures in the Tai Chi group, including the Mattis Dementia Rating Scale score (p = 0.004), the Trailmaking Test A (p = 0.002) and B (p = 0.0002), the Auditory Verbal Learning Test (p = 0.009), and verbal fluency for animals (p = 0.01). The Social Interaction group showed improvement on some, but fewer neuropsychological indices. No differences were observed between the Walking and No Intervention groups. The findings differ from previous clinical trials in showing increases in brain volume and improvements in cognition with a largely non-aerobic exercise (Tai Chi). In addition, intellectual stimulation through social interaction was associated with increases in brain volume as well as with some cognitive improvements.

An educational intervention on drug interactions and contraceptive options for epilepsy patients: a pilot randomized controlled trial.

PubMed

Mody, Sheila K; Haunschild, Carolyn; Farala, John Paul; Honerkamp-Smith, Gordon; Hur, Vivian; Kansal, Leena

2016-01-01

This pilot study investigates whether an educational handout could increase short-term information retention about drug interactions between antiepileptic drugs (AEDs) and hormonal contraceptives among female epilepsy patients of reproductive age. This is a pilot randomized controlled trial of an educational intervention among reproductive-age women with epilepsy in an academic neurology clinic. Investigators measured knowledge before and after participants received either usual care or the educational handout. The 10-question test assessed increased knowledge of which AEDs affected efficacy of certain hormonal contraceptives and was assessed by calculating the improvement in score between the pretest and posttest. The educational handout included the names of AEDs that have drug interactions with certain contraceptives and the efficacy of the contraceptives. A total of 42 epilepsy patients participated in this study. Fourteen participants were taking AEDs that are enzyme p450 inducers and 13 participants were taking Lamotrigine. Twenty women were randomized to receive the educational handout and 22 women were randomized to usual care. We found no statistical difference in the groups with regard to age, ethnicity or level of education. We found a significantly higher improvement in quiz scores in the educational handout group (3.65 point increase) compared to the usual care group (0.68 point increase) as calculated by the Student's two-sample t test (p<.001). An educational handout on drug interactions and contraceptives resulted in increased short-term information retention on this topic among reproductive-age female epilepsy patients. This pilot study highlights the need for further larger studies to evaluate the impact of educational interventions on improving patient knowledge about the drug interaction of AEDs and hormonal contraceptives. Copyright © 2016. Published by Elsevier Inc.

Main and Interaction Effects of Metallic Pollutants on Cognitive Functioning.

ERIC Educational Resources Information Center

Moon, Charles; And Others

1985-01-01

A study involving 69 randomly selected elementary students indicated that increases in arsenic and interaction of arsenic lead were significantly related to decreased reading and spelling achievement, and increases in aluminum and the interaction of aluminum with lead were significantly related to decreased visual-motor performance. (Author/CL)

Effectiveness of Interactive Video to Teach CPR Theory and Skills.

ERIC Educational Resources Information Center

Lyness, Ann L.

This study investigated whether an interactive video system of instruction taught cardiopulmonary resuscitation (CPR) as effectively as traditional instruction. Using standards of the American Heart Association, the study was designed with two randomized groups to be taught either by live instruction or by interactive video. Subjects were 100…

Matching Alcoholics to Coping Skills or Interactional Therapies: Posttreatment Results.

ERIC Educational Resources Information Center

Kadden, Ronald M.; And Others

1989-01-01

Randomly assigned 96 persons from inpatient alcoholism treatment program to aftercare group treatment consisting of either coping skills training or interactional therapy. Found that coping skills training was more effective for subjects higher in sociopathy or psychopathology; interactional therapy was more effective for subjects lower in…

Gossip and Distributed Kalman Filtering: Weak Consensus Under Weak Detectability

NASA Astrophysics Data System (ADS)

Kar, Soummya; Moura, José M. F.

2011-04-01

The paper presents the gossip interactive Kalman filter (GIKF) for distributed Kalman filtering for networked systems and sensor networks, where inter-sensor communication and observations occur at the same time-scale. The communication among sensors is random; each sensor occasionally exchanges its filtering state information with a neighbor depending on the availability of the appropriate network link. We show that under a weak distributed detectability condition: 1. the GIKF error process remains stochastically bounded, irrespective of the instability properties of the random process dynamics; and 2. the network achieves \\emph{weak consensus}, i.e., the conditional estimation error covariance at a (uniformly) randomly selected sensor converges in distribution to a unique invariant measure on the space of positive semi-definite matrices (independent of the initial state.) To prove these results, we interpret the filtered states (estimates and error covariances) at each node in the GIKF as stochastic particles with local interactions. We analyze the asymptotic properties of the error process by studying as a random dynamical system the associated switched (random) Riccati equation, the switching being dictated by a non-stationary Markov chain on the network graph.

Modeling soil respiration and variations of source components using a multi-factor global climate change experiment

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

Chen, Xiongwen; Post, Wilfred M; Norby, Richard J

2011-01-01

Soil respiration is an important component of the global carbon cycle and is highly responsive to changes in soil temperature and moisture. Accurate prediction of soil respiration and its changes under future climatic conditions requires a clear understanding of the processes involved. In spite of this, most current empirical soil respiration models incorporate just few of the underlying mechanisms that may influence its response. In this study, a new partial process-based component model built on source components of soil respiration was tested using data collected from a multi-factor climate change experiment that manipulates CO2 concentrations, temperature and precipitation. These resultsmore » were then compared to results generated using several other established models. The component model we tested performed well across different treatments of global climate change. In contrast, some other models, which worked well predicting ambient environmental conditions, were unable to predict the changes under different climate change treatments. Based on the component model, the relative proportions of heterotrophic respiration (Rh) in the total soil respiration at different treatments varied from 0.33 to 0.85. There is a significant increase in the proportion of Rh under the elevated atmospheric CO2 concentration in comparison ambient conditions. The dry treatment resulted in higher proportion of Rh at elevated CO2 and ambient T than under elevated CO2 and elevated T. Also, the ratios between root growth and root maintenance respiration varied across different treatments. Neither increased temperature nor elevated atmospheric CO2 changed Q10 values significantly, while the average Q10 value at wet sites was significantly higher than it at dry sites. There was a higher possibility of increased soil respiration under drying relative to wetting conditions across all treatments based on monthly data, indicating that soil respiration may also be related to soil moisture at previous time periods. Our results reveal that the extent, time delay and contribution of different source components need to be included into mechanistic/processes-based soil respiration models at corresponding scale.« less

Random sequences generation through optical measurements by phase-shifting interferometry

NASA Astrophysics Data System (ADS)

François, M.; Grosges, T.; Barchiesi, D.; Erra, R.; Cornet, A.

2012-04-01

The development of new techniques for producing random sequences with a high level of security is a challenging topic of research in modern cryptographics. The proposed method is based on the measurement by phase-shifting interferometry of the speckle signals of the interaction between light and structures. We show how the combination of amplitude and phase distributions (maps) under a numerical process can produce random sequences. The produced sequences satisfy all the statistical requirements of randomness and can be used in cryptographic schemes.

Protein Charge and Mass Contribute to the Spatio-temporal Dynamics of Protein-Protein Interactions in a Minimal Proteome

PubMed Central

Xu, Yu; Wang, Hong; Nussinov, Ruth; Ma, Buyong

2013-01-01

We constructed and simulated a ‘minimal proteome’ model using Langevin dynamics. It contains 206 essential protein types which were compiled from the literature. For comparison, we generated six proteomes with randomized concentrations. We found that the net charges and molecular weights of the proteins in the minimal genome are not random. The net charge of a protein decreases linearly with molecular weight, with small proteins being mostly positively charged and large proteins negatively charged. The protein copy numbers in the minimal genome have the tendency to maximize the number of protein-protein interactions in the network. Negatively charged proteins which tend to have larger sizes can provide large collision cross-section allowing them to interact with other proteins; on the other hand, the smaller positively charged proteins could have higher diffusion speed and are more likely to collide with other proteins. Proteomes with random charge/mass populations form less stable clusters than those with experimental protein copy numbers. Our study suggests that ‘proper’ populations of negatively and positively charged proteins are important for maintaining a protein-protein interaction network in a proteome. It is interesting to note that the minimal genome model based on the charge and mass of E. Coli may have a larger protein-protein interaction network than that based on the lower organism M. pneumoniae. PMID:23420643

A protocol for a randomized clinical trial of interactive video dance: potential for effects on cognitive function

PubMed Central

2012-01-01

Background Physical exercise has the potential to affect cognitive function, but most evidence to date focuses on cognitive effects of fitness training. Cognitive exercise also may influence cognitive function, but many cognitive training paradigms have failed to provide carry-over to daily cognitive function. Video games provide a broader, more contextual approach to cognitive training that may induce cognitive gains and have carry over to daily function. Most video games do not involve physical exercise, but some novel forms of interactive video games combine physical activity and cognitive challenge. Methods/Design This paper describes a randomized clinical trial in 168 postmenopausal sedentary overweight women that compares an interactive video dance game with brisk walking and delayed entry controls. The primary endpoint is adherence to activity at six months. Additional endpoints include aspects of physical and mental health. We focus this report primarily on the rationale and plans for assessment of multiple cognitive functions. Discussion This randomized clinical trial may provide new information about the cognitive effects of interactive videodance. It is also the first trial to examine physical and cognitive effects in older women. Interactive video games may offer novel strategies to promote physical activity and health across the life span. The study is IRB approved and the number is: PRO08080012 ClinicalTrials.gov Identifier: NCT01443455 PMID:22672287

Local random configuration-tree theory for string repetition and facilitated dynamics of glass

NASA Astrophysics Data System (ADS)

Lam, Chi-Hang

2018-02-01

We derive a microscopic theory of glassy dynamics based on the transport of voids by micro-string motions, each of which involves particles arranged in a line hopping simultaneously displacing one another. Disorder is modeled by a random energy landscape quenched in the configuration space of distinguishable particles, but transient in the physical space as expected for glassy fluids. We study the evolution of local regions with m coupled voids. At a low temperature, energetically accessible local particle configurations can be organized into a random tree with nodes and edges denoting configurations and micro-string propagations respectively. Such trees defined in the configuration space naturally describe systems defined in two- or three-dimensional physical space. A micro-string propagation initiated by a void can facilitate similar motions by other voids via perturbing the random energy landscape, realizing path interactions between voids or equivalently string interactions. We obtain explicit expressions of the particle diffusion coefficient and a particle return probability. Under our approximation, as temperature decreases, random trees of energetically accessible configurations exhibit a sequence of percolation transitions in the configuration space, with local regions containing fewer coupled voids entering the non-percolating immobile phase first. Dynamics is dominated by coupled voids of an optimal group size, which increases as temperature decreases. Comparison with a distinguishable-particle lattice model (DPLM) of glass shows very good quantitative agreements using only two adjustable parameters related to typical energy fluctuations and the interaction range of the micro-strings.

Common Randomness Principles of Secrecy

ERIC Educational Resources Information Center

Tyagi, Himanshu

2013-01-01

This dissertation concerns the secure processing of distributed data by multiple terminals, using interactive public communication among themselves, in order to accomplish a given computational task. In the setting of a probabilistic multiterminal source model in which several terminals observe correlated random signals, we analyze secure…

Effectiveness of interactive discussion group in suicide risk assessment among general nurses in Taiwan: a randomized controlled trial.

PubMed

Wu, Chia-Yi; Lin, Yi-Yin; Yeh, Mei Chang; Huang, Lian-Hua; Chen, Shaw-Ji; Liao, Shih-Cheng; Lee, Ming-Been

2014-11-01

The evidence of suicide prevention training for nurses is scarce. Strategies to enhance general nurses' ability in suicide risk assessment are critical to develop effective training programs in general medical settings. This study was aimed to examine the effectiveness of an interactive discussion group in a suicide prevention training program for general nurses. In this randomized study with two groups of pre-post study design, the sample was recruited from the Medical, Surgical, and Emergency/Intensive Care Sectors of a 2000-bed general hospital via stratified randomization. Among the 111 nurses, 57 participants randomly assigned to the control group received a two-hour baseline suicide gatekeeper lecture, and 54 participants assigning to the experimental group received an additional five-hour group discussion about suicide risk assessment skills. Using a case vignette, the nurses discussed and assessed suicide risk factors specified in a 10-item Chinese SAD PERSONS Scale during a group discussion intervention. The findings revealed that the nurses achieved significant and consistent improvements of risk identification and assessment after the intervention without influencing their mental health status for assessing suicide risks. The result suggested an effective approach of interactive group discussion for facilitating critical thinking and learning suicide risk assessment skills among general nurses. Copyright © 2014 Elsevier Ltd. All rights reserved.

Inhomogeneous fluid of penetrable-spheres: Application of the random phase approximation

NASA Astrophysics Data System (ADS)

Xiang, Yan; Frydel, Derek

2017-05-01

The focus of the present work is the application of the random phase approximation (RPA), derived for inhomogeneous fluids [Frydel and Ma, Phys. Rev. E 93, 062112 (2016)], to penetrable-spheres. As penetrable-spheres transform into hard-spheres with increasing interactions, they provide an interesting case for exploring the RPA, its shortcomings, and limitations, the weak- versus the strong-coupling limit. Two scenarios taken up by the present study are a one-component and a two-component fluid with symmetric interactions. In the latter case, the mean-field contributions cancel out and any contributions from particle interactions are accounted for by correlations. The accuracy of the RPA for this case is the result of a somewhat lucky cancellation of errors.

Many-body localization in a long range XXZ model with random-field

NASA Astrophysics Data System (ADS)

Li, Bo

2016-12-01

Many-body localization (MBL) in a long range interaction XXZ model with random field are investigated. Using the exact diagonal method, the MBL phase diagram with different tuning parameters and interaction range is obtained. It is found that the phase diagram of finite size results supplies strong evidence to confirm that the threshold interaction exponent α = 2. The tuning parameter Δ can efficiently change the MBL edge in high energy density stats, thus the system can be controlled to transfer from thermal phase to MBL phase by changing Δ. The energy level statistics data are consistent with result of the MBL phase diagram. However energy level statistics data cannot detect the thermal phase correctly in extreme long range case.

Internal force field in proteins seen by divergence entropy

PubMed Central

Marchewka, Damian; Banach, Mateusz; Roterman, Irena

2011-01-01

The characteristic distribution of non-binding interactions in a protein is described. It establishes that hydrophobic interactions can be characterized by suitable 3D Gauss functions while electrostatic interactions generally follow a random distribution. The implementation of this observation suggests differentiated optimization procedure for these two types of interactions. The electrostatic interaction may follow traditional energy optimization while the criteria for convergence shall measure the accordance with 3-D Gauss function. PMID:21769190

A Course on Effective Teacher-Child Interactions. Research Brief

ERIC Educational Resources Information Center

Hamre, Bridget K.; Pianta, Robert C.; Burchinal, Margaret; Field, Samuel; LoCasale-Crouch, Jennifer; Downer, Jason T.; Howes, Carollee; LaParo, Karen; Scott-Little, Catherine

2012-01-01

This study found that teachers who were randomly assigned to take a 14-week course on effective teacher-child interactions demonstrated significant changes in beliefs and knowledge about effective practices and provided more stimulating and engaging interactions in the classroom. [This research brief is based on: Hamre, B. K., Pianta, R. C.,…

Media Embedded Interactions.

ERIC Educational Resources Information Center

Johnson, J. David

A review of literature and two surveys, one of college students and one of a random sample of adults, were used to examine four aspects of media embedded interactions (social behavior in front of a TV or radio): their functions, their environment, their effects, and the reactions of the interactants to them. Television is seen as performing a…

Conditions where random phase approximation becomes exact in the high-density limit

NASA Astrophysics Data System (ADS)

Morawetz, Klaus; Ashokan, Vinod; Bala, Renu; Pathak, Kare Narain

2018-04-01

It is shown that, in d -dimensional systems, the vertex corrections beyond the random phase approximation (RPA) or G W approximation scales with the power d -β -α of the Fermi momentum if the relation between Fermi energy and Fermi momentum is ɛf˜pfβ and the interacting potential possesses a momentum power law of ˜p-α . The condition d -β -α <0 specifies systems where RPA is exact in the high-density limit. The one-dimensional structure factor is found to be the interaction-free one in the high-density limit for contact interaction. A cancellation of RPA and vertex corrections render this result valid up to second order in contact interaction. For finite-range potentials of cylindrical wires a large-scale cancellation appears and is found to be independent of the width parameter of the wire. The proposed high-density expansion agrees with the quantum Monte Carlo simulations.

Mapping protein-protein interactions using yeast two-hybrid assays.

PubMed

Mehla, Jitender; Caufield, J Harry; Uetz, Peter

2015-05-01

Yeast two-hybrid (Y2H) screens are an efficient system for mapping protein-protein interactions and whole interactomes. The screens can be performed using random libraries or collections of defined open reading frames (ORFs) called ORFeomes. This protocol describes both library and array-based Y2H screening, with an emphasis on array-based assays. Array-based Y2H is commonly used to test a number of "prey" proteins for interactions with a single "bait" (target) protein or pool of proteins. The advantage of this approach is the direct identification of interacting protein pairs without further downstream experiments: The identity of the preys is known and does not require further confirmation. In contrast, constructing and screening a random prey library requires identification of individual prey clones and systematic retesting. Retesting is typically performed in an array format. © 2015 Cold Spring Harbor Laboratory Press.

Realistic Many-Body Quantum Systems vs. Full Random Matrices: Static and Dynamical Properties

NASA Astrophysics Data System (ADS)

Karp, Jonathan; Torres-Herrera, Jonathan; TáVora, Marco; Santos, Lea

We study the static and dynamical properties of isolated spin 1/2 systems as prototypes of many-body quantum systems and compare the results to those of full random matrices from a Gaussian orthogonal ensemble. Full random matrices do not represent realistic systems, because they imply that all particles interact at the same time, as opposed to realistic Hamiltonians, which are sparse and have only few-body interactions. Nevertheless, with full random matrices we can derive analytical results that can be used as references and bounds for the corresponding properties of realistic systems. In particular, we show that the results for the Shannon information entropy are very similar to those for the von Neumann entanglement entropy, with the former being computationally less expensive. We also discuss the behavior of the survival probability of the initial state at different time scales and show that it contains more information about the system than the entropies. Support from the NSF Grant No. DMR-1147430.

On the source of stochastic volatility: Evidence from CAC40 index options during the subprime crisis

NASA Astrophysics Data System (ADS)

Slim, Skander

2016-12-01

This paper investigates the performance of time-changed Lévy processes with distinct sources of return volatility variation for modeling cross-sectional option prices on the CAC40 index during the subprime crisis. Specifically, we propose a multi-factor stochastic volatility model: one factor captures the diffusion component dynamics and two factors capture positive and negative jump variations. In-sample and out-of-sample tests show that our full-fledged model significantly outperforms nested lower-dimensional specifications. We find that all three sources of return volatility variation, with different persistence, are needed to properly account for market pricing dynamics across moneyness, maturity and volatility level. Besides, the model estimation reveals negative risk premium for both diffusive volatility and downward jump intensity whereas a positive risk premium is found to be attributed to upward jump intensity.

[Development of the lung cancer diagnostic system].

PubMed

Lv, You-Jiang; Yu, Shou-Yi

2009-07-01

To develop a lung cancer diagnosis system. A retrospective analysis was conducted in 1883 patients with primary lung cancer or benign pulmonary diseases (pneumonia, tuberculosis, or pneumonia pseudotumor). SPSS11.5 software was used for data processing. For the relevant factors, a non-factor Logistic regression analysis was used followed by establishment of the regression model. Microsoft Visual Studio 2005 system development platform and VB.Net corresponding language were used to develop the lung cancer diagnosis system. The non-factor multi-factor regression model showed a goodness-of-fit (R2) of the model of 0.806, with a diagnostic accuracy for benign lung diseases of 92.8%, a diagnostic accuracy for lung cancer of 89.0%, and an overall accuracy of 90.8%. The model system for early clinical diagnosis of lung cancer has been established.

Confidence in delegation and leadership of registered nurses in long-term-care hospitals.

PubMed

Yoon, Jungmin; Kim, Miyoung; Shin, Juhhyun

2016-07-01

Effective delegation improves job satisfaction, responsibility, productivity and development. The ageing population demands more nurses in long-term-care hospitals. Delegation and leadership promote cooperation among nursing staff. However, little research describes nursing delegation and leadership style. We investigated the relationship between registered nurses' delegation confidence and leadership in Korean long-term-care hospitals. Our descriptive correlational design sampled 199 registered nurses from 13 long-term-care hospitals in Korea. Instruments were the Confidence and Intent to Delegate Scale and Multifactor Leadership Questionnaire. Confidence in delegation significantly aligned with current-unit clinical experience, length of total clinical-nursing experience, delegation-training experience and leadership. Transformational leadership was the most statistically significant factor influencing delegation confidence. When effective delegation integrates with efficient leadership, staff can deliver optimal care to long-term-care patients. © 2016 John Wiley & Sons Ltd.

Application of Analytic Hierarchy Process (AHP) in the analysis of the fuel efficiency in the automobile industry with the utilization of Natural Fiber Polymer Composites (NFPC)

NASA Astrophysics Data System (ADS)

Jayamani, E.; Perera, D. S.; Soon, K. H.; Bakri, M. K. B.

2017-04-01

A systematic method of material analysis aiming for fuel efficiency improvement with the utilization of natural fiber reinforced polymer matrix composites in the automobile industry is proposed. A multi-factor based decision criteria with Analytical Hierarchy Process (AHP) was used and executed through MATLAB to achieve improved fuel efficiency through the weight reduction of vehicular components by effective comparison between two engine hood designs. The reduction was simulated by utilizing natural fiber polymer composites with thermoplastic polypropylene (PP) as the matrix polymer and benchmarked against a synthetic based composite component. Results showed that PP with 35% of flax fiber loading achieved a 0.4% improvement in fuel efficiency, and it was the highest among the 27 candidate fibers.

[Youth drinking as en example of relationship between risk behaviour and knowledge on its effects].

PubMed

Wrona-Wolny, Weronika; Brudecki, Janusz

2006-01-01

Using psychoactive substances like smoking, drinking or drugs are most common risky behaviour. In the article only drinking as an examples was analysed. Knowledge about alcohol health effects and its dependence on undertaking risky behaviour, alcohol-advertisement perception, sex and group were analysed. Between 2001 and 2005 343 sportsmen and 400 students as a control group were participated in research. Questionnaire diagnosed alcohol-related behaviour and alcohol-advertisement perceptions were used. Knowledge about effects of alcohol acting contains 11 questions. Chi-square test and multifactor analysis of variances were used. Results show that knowledge level depends only from group belonging and is higher in students than sportsmen. Susceptibility to undertaking risky behaviour occurs more frequently in control than in sport group, in man then woman, and in person with who pay attention to alcohol advertisements.

A business case evaluation of workplace engineering noise control: a net-cost model.

PubMed

Lahiri, Supriya; Low, Colleen; Barry, Michael

2011-03-01

This article provides a convenient tool for companies to determine the costs and benefits of alternative interventions to prevent noise-induced hearing loss (NIHL). Contextualized for Singapore and in collaboration with Singapore's Ministry of Manpower, the Net-Cost model evaluates costs of intervention for equipment and labor, avoided costs of productivity losses and medical care, and productivity gains from the employer's economic perspective. To pilot this approach, four case studies are presented, with varying degrees of economic benefits to the employer, including one in which multifactor productivity is the main driver. Although compliance agencies may not require economic analysis of NIHL, given scarce resources in a market-driven economy, this tool enables stakeholders to understand and compare the costs and benefits of NIHL interventions comprehensively and helps in determining risk management strategies.

The natural moon illusion: a multifactor angular account.

PubMed

Plug, C; Ross, H E

1994-01-01

It is argued that the failure to explain the celestial illusion results from conceptual confusion about perceived size and from disregard of the observational evidence relating to the natural moon illusion. The evidence shows that the illusion consists of a perceived angular size enlargement of horizon objects, by a factor of about 1.5-2.0 in diameter in comparison with elevated objects. Most measurements of the illusion have been made in terms of angular size, although in some proposed explanations an illusion of linear size is assumed. The magnitude of the illusion varies, particularly with the detail of the horizon scene. The illusion can be explained as the sum of several factors that affect perceived angular size: size contrast, vergence commands and eye or head position, aerial perspective, and colour. The relative contributions of these factors are assessed.

Drug development costs when financial risk is measured using the Fama-French three-factor model.

PubMed

Vernon, John A; Golec, Joseph H; Dimasi, Joseph A

2010-08-01

In a widely cited article, DiMasi, Hansen, and Grabowski (2003) estimate the average pre-tax cost of bringing a new molecular entity to market. Their base case estimate, excluding post-marketing studies, was $802 million (in $US 2000). Strikingly, almost half of this cost (or $399 million) is the cost of capital (COC) used to fund clinical development expenses to the point of FDA marketing approval. The authors used an 11% real COC computed using the capital asset pricing model (CAPM). But the CAPM is a single factor risk model, and multi-factor risk models are the current state of the art in finance. Using the Fama-French three factor model we find that the cost of drug development to be higher than the earlier estimate. Copyright (c) 2009 John Wiley & Sons, Ltd.

Migration, health, and socioenvironmental safety net among children of Dhaka, Bangladesh.

PubMed

Molla, Neelima Afroz; Ali, Ghaffar; Mollah, Kabirul Ahsan; Wongwit, Waranya; Shipin, Oleg; Ramasoota, Pongrama; Nur, Husna Parvin

2017-11-02

This study quantifies the diarrhea burden among migrant children under age 5 (who have migrated due to environmental degradation) in Dhaka. We used a multifactor socioepidemiological as well as environmental approach with pretested questionnaires and observations. It was found that 52% of the children were affected by diarrhea. Disability-adjusted life years (DALYs) lost was reduced manifold with the increase of mothers' behavioral determinants. Health losses were 1,718 fold with significant coefficient (β) in the migrant group. DALYs lost were significantly associated with socioenvironmental factors such as mother's illiteracy (β = .18; p < .001), no hand wash before eating (β = .08; p = .004), and no hand wash after defecation (β = .10; p < .001). This puts emphasis clearly on the awareness at household level, especially of mothers and children under age 5 in Dhaka, Bangladesh, in formulating migration-related policies.

Curcumin―The Paradigm of a Multi-Target Natural Compound with Applications in Cancer Prevention and Treatment

PubMed Central

Teiten, Marie-Hélène; Eifes, Serge; Dicato, Mario; Diederich, Marc

2010-01-01

As cancer is a multifactor disease, it may require treatment with compounds able to target multiple intracellular components. We summarize here how curcumin is able to modulate many components of intracellular signaling pathways implicated in inflammation, cell proliferation and invasion and to induce genetic modulations eventually leading to tumor cell death. Clinical applications of this natural compound were initially limited by its low solubility and bioavailability in both plasma and tissues but combination with adjuvant and delivery vehicles was reported to largely improve bio-availability of curcumin. Moreover, curcumin was reported to act in synergism with several natural compounds or synthetic agents commonly used in chemotherapy. Based on this, curcumin could thus be considered as a good candidate for cancer prevention and treatment when used alone or in combination with other conventional treatments. PMID:22069551

Optical Interactions at Randomly Rough Surfaces

DTIC Science & Technology

2003-03-10

frequency range. The design of a random surface that acts as a Lambertian diffuser, especially in the infrared region of the optical spectrum, is...FTIR grazing angle microscopy. Recently, an experimental study was performed of the far-field scattering at small grazing angles, especially the enhanced...a specular component in the scattered light, in this frequency range. The design of a random surface that acts as a Lambertian diffuser, especially in

Differentiating emotions across contexts: comparing adults with and without social anxiety disorder using random, social interaction, and daily experience sampling.

PubMed

Kashdan, Todd B; Farmer, Antonina S

2014-06-01

The ability to recognize and label emotional experiences has been associated with well-being and adaptive functioning. This skill is particularly important in social situations, as emotions provide information about the state of relationships and help guide interpersonal decisions, such as whether to disclose personal information. Given the interpersonal difficulties linked to social anxiety disorder (SAD), deficient negative emotion differentiation may contribute to impairment in this population. We hypothesized that people with SAD would exhibit less negative emotion differentiation in daily life, and these differences would translate to impairment in social functioning. We recruited 43 people diagnosed with generalized SAD and 43 healthy adults to describe the emotions they experienced over 14 days. Participants received palmtop computers for responding to random prompts and describing naturalistic social interactions; to complete end-of-day diary entries, they used a secure online website. We calculated intraclass correlation coefficients to capture the degree of differentiation of negative and positive emotions for each context (random moments, face-to-face social interactions, and end-of-day reflections). Compared to healthy controls, the SAD group exhibited less negative (but not positive) emotion differentiation during random prompts, social interactions, and (at trend level) end-of-day assessments. These differences could not be explained by emotion intensity or variability over the 14 days, or to comorbid depression or anxiety disorders. Our findings suggest that people with generalized SAD have deficits in clarifying specific negative emotions felt at a given point of time. These deficits may contribute to difficulties with effective emotion regulation and healthy social relationship functioning.

On the equilibrium state of a small system with random matrix coupling to its environment

NASA Astrophysics Data System (ADS)

Lebowitz, J. L.; Pastur, L.

2015-07-01

We consider a random matrix model of interaction between a small n-level system, S, and its environment, a N-level heat reservoir, R. The interaction between S and R is modeled by a tensor product of a fixed n× n matrix and a N× N Hermitian random matrix. We show that under certain ‘macroscopicity’ conditions on R, the reduced density matrix of the system {{ρ }S}=T{{r}R}ρ S\\cup R(eq), is given by ρ S(c)˜ exp \\{-β {{H}S}\\}, where HS is the Hamiltonian of the isolated system. This holds for all strengths of the interaction and thus gives some justification for using ρ S(c) to describe some nano-systems, like biopolymers, in equilibrium with their environment (Seifert 2012 Rep. Prog. Phys. 75 126001). Our results extend those obtained previously in (Lebowitz and Pastur 2004 J. Phys. A: Math. Gen. 37 1517-34) (Lebowitz et al 2007 Contemporary Mathematics (Providence RI: American Mathematical Society) pp 199-218) for a special two-level system.