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.
NASA Technical Reports Server (NTRS)
Bast, Callie C.; Boyce, Lola
1995-01-01
The development of methodology for a probabilistic material strength degradation is described. 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. 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 predictions of high-cycle mechanical fatigue and high temperature effects with experiments are presented. Results from this limited verification study strongly supported that material degradation can be represented by randomized multifactor interaction models.
Probabilistic lifetime strength of aerospace materials via computational simulation
NASA Technical Reports Server (NTRS)
Boyce, Lola; Keating, Jerome P.; Lovelace, Thomas B.; Bast, Callie C.
1991-01-01
The results of a second year effort of a research program are presented. The research included development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic phenomenological constitutive relationship, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects of primitive variables. These primitive variables often originate in the environment and may include stress from loading, temperature, chemical, or radiation attack. This multifactor interaction constitutive equation is included in the computer program, PROMISS. Also included in the research is the development of methodology to calibrate the constitutive equation using actual experimental materials data together with the multiple linear regression of that data.
NASA Technical Reports Server (NTRS)
Boyce, Lola; Bast, Callie C.
1992-01-01
The research included ongoing development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects or primative variables. These primative variable may include high temperature, fatigue or creep. In most cases, strength is reduced as a result of the action of a variable. This multifactor interaction strength degradation equation has been randomized and is included in the computer program, PROMISS. Also included in the research is the development of methodology to calibrate the above described constitutive equation using actual experimental materials data together with linear regression of that data, thereby predicting values for the empirical material constraints for each effect or primative variable. This regression methodology is included in the computer program, PROMISC. Actual experimental materials data were obtained from the open literature for materials typically of interest to those studying aerospace propulsion system components. Material data for Inconel 718 was analyzed using the developed methodology.
NASA Technical Reports Server (NTRS)
Boyce, Lola; Bast, Callie C.; Trimble, Greg A.
1992-01-01
This report presents the results of a fourth 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 that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subject to a number of effects or primitive variables. These primitive variables may include high temperature, fatigue or creep. In most cases, strength is reduced as a result of the action of a variable. This multifactor interaction strength degradation equation has been randomized and is included in the computer program, PROMISS. Also included in the research is the development of methodology to calibrate the above-described constitutive equation using actual experimental materials data together with regression analysis of that data, thereby predicting values for the empirical material constants for each effect or primitive variable. This regression methodology is included in the computer program, PROMISC. Actual experimental materials data were obtained from industry and the open literature for materials typically for applications in aerospace propulsion system components. Material data for Inconel 718 has been analyzed using the developed methodology.
NASA Technical Reports Server (NTRS)
Boyce, Lola; Bast, Callie C.; Trimble, Greg A.
1992-01-01
The results of a fourth year effort of a research program conducted for NASA-LeRC by The University of Texas at San Antonio (UTSA) are presented. The research included on-going development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects or primitive variables. These primitive variables may include high temperature, fatigue, or creep. In most cases, strength is reduced as a result of the action of a variable. This multifactor interaction strength degradation equation was randomized and is included in the computer program, PROMISC. Also included in the research is the development of methodology to calibrate the above-described constitutive equation using actual experimental materials data together with regression analysis of that data, thereby predicting values for the empirical material constants for each effect or primitive variable. This regression methodology is included in the computer program, PROMISC. Actual experimental materials data were obtained from industry and the open literature for materials typically for applications in aerospace propulsion system components. Material data for Inconel 718 was analyzed using the developed methodology.
Barnestein-Fonseca, Pilar; Leiva-Fernández, José; Vidal-España, Francisca; García-Ruiz, Antonio; Prados-Torres, Daniel; Leiva-Fernández, Francisca
2011-02-14
Low therapeutic adherence to medication is very common. Clinical effectiveness is related to dose rate and route of administration and so poor therapeutic adherence can reduce the clinical benefit of treatment. The therapeutic adherence of patients with chronic obstructive pulmonary disease (COPD) is extremely poor according to most studies. The research about COPD adherence has mainly focussed on quantifying its effect, and few studies have researched factors that affect non-adherence. Our study will evaluate the effectiveness of a multifactor intervention to improve the therapeutic adherence of COPD patients. A randomized controlled clinical trial with 140 COPD diagnosed patients selected by a non-probabilistic method of sampling. Subjects will be randomly allocated into two groups, using the block randomization technique. Every patient in each group will be visited four times during the year of the study. Motivational aspects related to adherence (beliefs and behaviour): group and individual interviews; cognitive aspects: information about illness; skills: inhaled technique training. Reinforcement of the cognitive-emotional aspects and inhaled technique training will be carried out in all visits of the intervention group. Adherence to a prescribed treatment involves a behavioural change. Cognitive, emotional and motivational aspects influence this change and so we consider the best intervention procedure to improve adherence would be a cognitive and emotional strategy which could be applied in daily clinical practice. Our hypothesis is that the application of a multifactor intervention (COPD information, dose reminders and reinforcing audiovisual material, motivational aspects and inhalation technique training) to COPD patients taking inhaled treatment will give a 25% increase in the number of patients showing therapeutic adherence in this group compared to the control group.We will evaluate the effectiveness of this multifactor intervention on patient adherence to inhaled drugs considering that it will be right and feasible to the clinical practice context. Current Controlled Trials ISRCTN18841601.
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.
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…
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...
[Homeostatic range of the oxidative metabolism: 60 years of integrative fisiometry].
Günther, Bruno; Morgado, Enrique; Cociña, Manuela
2005-03-01
The energetic metabolism and its relationship with body weight generated a vivid controversy, since the Rubner's surface law was introduced into biology. Recently, the multifactor theory (Darveau et al) has caused again a revival of this polemic topic. Moreover, the investigations concerning metabolism and body weight include all terrestrial mammals, from the shrew (3 grams) to the elephant (three tons). The corresponding allometric exponent for standard metabolic rate, both theoretical and empirical, fluctuates around an average value of 0.75, in contrast with the surface law, which postulated a value of 0.67. The "metabolic range" (rest vs maximal exercise) does vary from 1 to 10, due to the prevalent influence of the skeletal muscle activity. Recent investigations have emphasized the fact that the allometric exponent is not unique (0.75), but it should be subjected to statistical variability, both in standard and in maximal exercise.
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
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.
The keloid phenomenon: progress toward a solution.
Louw, Louise
2007-01-01
For centuries, keloids have been an enigma and despite considerable research to unravel this phenomenon no universally accepted treatment protocol currently exists. Historically, the etiology of keloids has been hypothesized by multiple different theories; however, a more contemporary view postulates a multifactoral basis for this disorder involving nutritional, biochemical, immunological, and genetic factors that play a role in this abnormal wound healing. Critical to the process of preventing or managing keloids is the need to locally control fibroblasts and their activities at the wound site. In recent years, considerable evidence has accumulated demonstrating the importance of fatty acids and bioactive lipids in health and disease, especially those involving inflammatory disorders or immune dysfunction. If hypertrophic scarring and keloid formation can be argued to have significant inflammatory histories, then it is possible to postulate a role for lipids in their etiology and potentially in their treatment. This report briefly visits past views and theories on keloid formation and treatment, and offers a theoretical rationale for considering adjuvant fatty acid therapy for keloid management. Sufficient scientific evidence in support of fatty acid strategies for the prevention and treatment of keloids currently exists, which offer opportunities to bridge the gap between the laboratory and the clinic. The intent of this paper is to serve as a basic guideline for researchers, nutritionists, and clinicians interested in keloids and to propose new directions for keloid management.
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
A random spatial network model based on elementary postulates
Karlinger, Michael R.; Troutman, Brent M.
1989-01-01
A model for generating random spatial networks that is based on elementary postulates comparable to those of the random topology model is proposed. In contrast to the random topology model, this model ascribes a unique spatial specification to generated drainage networks, a distinguishing property of some network growth models. The simplicity of the postulates creates an opportunity for potential analytic investigations of the probabilistic structure of the drainage networks, while the spatial specification enables analyses of spatially dependent network properties. In the random topology model all drainage networks, conditioned on magnitude (number of first-order streams), are equally likely, whereas in this model all spanning trees of a grid, conditioned on area and drainage density, are equally likely. As a result, link lengths in the generated networks are not independent, as usually assumed in the random topology model. For a preliminary model evaluation, scale-dependent network characteristics, such as geometric diameter and link length properties, and topologic characteristics, such as bifurcation ratio, are computed for sets of drainage networks generated on square and rectangular grids. Statistics of the bifurcation and length ratios fall within the range of values reported for natural drainage networks, but geometric diameters tend to be relatively longer than those for natural networks.
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.
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...
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.
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.
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.
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.
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).
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.
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
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...
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
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…
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.
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.
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.
Probabilistic Multi-Factor Interaction Model for Complex Material Behavior
NASA Technical Reports Server (NTRS)
Chamis, Christos C.; Abumeri, Galib H.
2008-01-01
The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the launch external 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 was 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.
Probabilistic Multi-Factor Interaction Model for Complex Material Behavior
NASA Technical Reports Server (NTRS)
Chamis, Christos C.; Abumeri, Galib H.
2008-01-01
The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the launch external 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 was 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.
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.
About Perpetuum Mobile without Emotions
NASA Astrophysics Data System (ADS)
Nikulov, Alexey
2002-11-01
It is noted that old belief in impossibility of any perpetuum mobile is the basis of the great confidence in the second law of thermodynamics. The Carnot's principle, «called with the time of Rudolf Clausius as the second law of thermodynamics», was based on this belief and this belief saved the second law in the beginning of 20 century when absolute randomness of any Brownian motion, perpetual motion experimentally observed, was postulated. It is shown that this postulate is not correct according to quantum mechanics. Moreover experimental evidence of its violation is known. Violation of this postulate means violation of the second law and a possibility of useful perpetuum mobile.
NASA Technical Reports Server (NTRS)
Chamis, Christos C.; Abumeri, Galib H.
2010-01-01
The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the launch external 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 was 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.
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
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.
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.
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.
Probabilistic Usage of the Multi-Factor Interaction Model
NASA Technical Reports Server (NTRS)
Chamis, Christos C.
2008-01-01
A Multi-Factor Interaction Model (MFIM) is used to predict the insulating foam mass expulsion during the ascending of a space vehicle. The exponents in the MFIM are evaluated by an available approach which consists of least squares and an optimization algorithm. These results were subsequently used to probabilistically evaluate the effects of the uncertainties in each participating factor in the mass expulsion. The probabilistic results show that the surface temperature dominates at high probabilities and the pressure which causes the mass expulsion at low probabil
Security enhanced multi-factor biometric authentication scheme using bio-hash function
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
NASA Astrophysics Data System (ADS)
De Kauwe, M. G.; Medlyn, B.; Walker, A.; Zaehle, S.; Pendall, E.; Norby, R. J.
2017-12-01
Multifactor experiments are often advocated as important for advancing models, yet to date, such models have only been tested against single-factor experiments. We applied 10 models to the multifactor Prairie Heating and CO2 Enrichment (PHACE) experiment in Wyoming, USA. Our goals were to investigate how multifactor experiments can be used to constrain models and to identify a road map for model improvement. We found models performed poorly in ambient conditions: comparison with data highlighted model failures particularly with respect to carbon allocation, phenology, and the impact of water stress on phenology. Performance against the observations from single-factors treatments 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 overestimated the effect of warming on leaf onset and did not allow CO2-induced water savings to extend the growing season length. Observed interactive (CO2 × warming) treatment effects were subtle and contingent on water stress, phenology, and species composition. As 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. 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.
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.
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.
The Human Performance Envelope: Past Research, Present Activities and Future Directions
NASA Technical Reports Server (NTRS)
Edwards, Tamsyn
2017-01-01
Air traffic controllers (ATCOs) must maintain a consistently high level of human performance in order to maintain flight safety and efficiency. In current control environments, performance-influencing factors such as workload, fatigue and situation awareness can co-occur, and interact, to effect performance. However, multifactor influences and the association with performance are under-researched. This study utilized a high fidelity human in the loop enroute air traffic control simulation to investigate the relationship between workload, situation awareness and ATCO performance. The study aimed to replicate and extend Edwards, Sharples, Wilson and Kirwans (2012) previous study and confirm multifactor interactions with a participant sample of ex-controllers. The study also aimed to extend Edwards et als previous research by comparing multifactor relationships across 4 automation conditions. Results suggest that workload and SA may interact to produce a cumulative impact on controller performance, although the effect of the interaction on performance may be dependent on the context and amount of automation present. Findings have implications for human-automation teaming in air traffic control, and the potential prediction and support of ATCO performance.
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.
De Kauwe, Martin G; Medlyn, Belinda E; Walker, Anthony P; Zaehle, Sönke; Asao, Shinichi; Guenet, Bertrand; Harper, Anna B; Hickler, Thomas; Jain, Atul K; Luo, Yiqi; Lu, Xingjie; Luus, Kristina; Parton, William J; Shu, Shijie; Wang, Ying-Ping; Werner, Christian; Xia, Jianyang; Pendall, Elise; Morgan, Jack A; Ryan, Edmund M; Carrillo, Yolima; Dijkstra, Feike A; Zelikova, Tamara J; Norby, Richard J
2017-09-01
Multifactor 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 multifactor Prairie Heating and CO 2 Enrichment (PHACE) experiment in Wyoming, USA. Our goals were to investigate how multifactor 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 particularly with respect to carbon allocation, phenology, and the impact of water stress on phenology. Performance against the observations from single-factors treatments 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 N cycle models, N availability during the experiment. Models were also unable to capture observed treatment effects on phenology: they overestimated the effect of warming on leaf onset and did not allow CO 2 -induced water savings to extend the growing season length. Observed interactive (CO 2 × warming) treatment effects were subtle and contingent on water stress, phenology, and species composition. As 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. 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. © 2017 John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Kauwe, Martin G.; Medlyn, Belinda E.; Walker, Anthony P.
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
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
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.
Severe chronic heart failure in patients considered for heart transplantation in Poland.
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.
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.
Gui, Jiang; Moore, Jason H.; Williams, Scott M.; Andrews, Peter; Hillege, Hans L.; van der Harst, Pim; Navis, Gerjan; Van Gilst, Wiek H.; Asselbergs, Folkert W.; Gilbert-Diamond, Diane
2013-01-01
We present an extension of the two-class multifactor dimensionality reduction (MDR) algorithm that enables detection and characterization of epistatic SNP-SNP interactions in the context of a quantitative trait. The proposed Quantitative MDR (QMDR) method handles continuous data by modifying MDR’s constructive induction algorithm to use a T-test. QMDR replaces the balanced accuracy metric with a T-test statistic as the score to determine the best interaction model. We used a simulation to identify the empirical distribution of QMDR’s testing score. We then applied QMDR to genetic data from the ongoing prospective Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. PMID:23805232
Computational analysis of gene-gene interactions using multifactor dimensionality reduction.
Moore, Jason H
2004-11-01
Understanding the relationship between DNA sequence variations and biologic traits is expected to improve the diagnosis, prevention and treatment of common human diseases. Success in characterizing genetic architecture will depend on our ability to address nonlinearities in the genotype-to-phenotype mapping relationship as a result of gene-gene interactions, or epistasis. This review addresses the challenges associated with the detection and characterization of epistasis. A novel strategy known as multifactor dimensionality reduction that was specifically designed for the identification of multilocus genetic effects is presented. Several case studies that demonstrate the detection of gene-gene interactions in common diseases such as atrial fibrillation, Type II diabetes and essential hypertension are also discussed.
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.
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.
The emotional memory effect: differential processing or item distinctiveness?
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.
USDA-ARS?s Scientific Manuscript database
Tropical enteropathy is characterized by an increased urinary lactulose-to-mannitol (L:M) ratio on a site-specific sugar absorption test and is associated with increased intestinal permeability and decreased nutrient absorptive capacity. The etiology of tropical enteropathy is postulated to be intes...
On the Determinants of the Conjunction Fallacy: Probability versus Inductive Confirmation
ERIC Educational Resources Information Center
Tentori, Katya; Crupi, Vincenzo; Russo, Selena
2013-01-01
Major recent interpretations of the conjunction fallacy postulate that people assess the probability of a conjunction according to (non-normative) averaging rules as applied to the constituents' probabilities or represent the conjunction fallacy as an effect of random error in the judgment process. In the present contribution, we contrast such…
Can Vitex Agnus Castus be Used for the Treatment of Mastalgia? What is the Current Evidence?
2008-01-01
There have been many treatments suggested for the management of mastalgia; one of these is the fruit extract of Vitex Agnus castus L. commonly known as Agnus castus, an extract of a deciduous shrub native to Mediterranean Europe and Central Asia. It is postulated that A. castus suppresses the stress-induced latent hyperprolactinemia which is a release of supra-physiological levels of prolactin in some patients in response to stressful stimuli. It is postulated that A. castus could be effective in the treatment of cyclical mastalgia by inhibiting the release of excess prolactin by blocking Dopamine-2 receptor type on pituitary. The adverse events following A. castus treatment are mild and reversible. The aim of this review is assess the efficacy of A. castus in the treatment of mastalgia. Data from randomized and non-randomized studies regarding the efficacy and safety of A. castus is reviewed in a systematic fashion. It is concluded that A. castus can be considered as an efficient alternative phytotherapeutic agent in the treatment of mastalgia. PMID:18830450
Can Vitex Agnus Castus be Used for the Treatment of Mastalgia? What is the Current Evidence?
Carmichael, A R
2008-09-01
There have been many treatments suggested for the management of mastalgia; one of these is the fruit extract of Vitex Agnus castus L. commonly known as Agnus castus, an extract of a deciduous shrub native to Mediterranean Europe and Central Asia. It is postulated that A. castus suppresses the stress-induced latent hyperprolactinemia which is a release of supra-physiological levels of prolactin in some patients in response to stressful stimuli. It is postulated that A. castus could be effective in the treatment of cyclical mastalgia by inhibiting the release of excess prolactin by blocking Dopamine-2 receptor type on pituitary. The adverse events following A. castus treatment are mild and reversible. The aim of this review is assess the efficacy of A. castus in the treatment of mastalgia. Data from randomized and non-randomized studies regarding the efficacy and safety of A. castus is reviewed in a systematic fashion. It is concluded that A. castus can be considered as an efficient alternative phytotherapeutic agent in the treatment of mastalgia.
Gui, Jiang; Andrew, Angeline S.; Andrews, Peter; Nelson, Heather M.; Kelsey, Karl T.; Karagas, Margaret R.; Moore, Jason H.
2010-01-01
A central goal of human genetics is to identify and characterize susceptibility genes for common complex human diseases. An important challenge in this endeavor is the modeling of gene-gene interaction or epistasis that can result in non-additivity of genetic effects. The multifactor dimensionality reduction (MDR) method was developed as machine learning alternative to parametric logistic regression for detecting interactions in absence of significant marginal effects. The goal of MDR is to reduce the dimensionality inherent in modeling combinations of polymorphisms using a computational approach called constructive induction. Here, we propose a Robust Multifactor Dimensionality Reduction (RMDR) method that performs constructive induction using a Fisher’s Exact Test rather than a predetermined threshold. The advantage of this approach is that only those genotype combinations that are determined to be statistically significant are considered in the MDR analysis. We use two simulation studies to demonstrate that this approach will increase the success rate of MDR when there are only a few genotype combinations that are significantly associated with case-control status. We show that there is no loss of success rate when this is not the case. We then apply the RMDR method to the detection of gene-gene interactions in genotype data from a population-based study of bladder cancer in New Hampshire. PMID:21091664
A Combinatorial Approach to Detecting Gene-Gene and Gene-Environment Interactions in Family Studies
Lou, Xiang-Yang; Chen, Guo-Bo; Yan, Lei; Ma, Jennie Z.; Mangold, Jamie E.; Zhu, Jun; Elston, Robert C.; Li, Ming D.
2008-01-01
Widespread multifactor interactions present a significant challenge in determining risk factors of complex diseases. Several combinatorial approaches, such as the multifactor dimensionality reduction (MDR) method, have emerged as a promising tool for better detecting gene-gene (G × G) and gene-environment (G × E) interactions. We recently developed a general combinatorial approach, namely the generalized multifactor dimensionality reduction (GMDR) method, which can entertain both qualitative and quantitative phenotypes and allows for both discrete and continuous covariates to detect G × G and G × E interactions in a sample of unrelated individuals. In this article, we report the development of an algorithm that can be used to study G × G and G × E interactions for family-based designs, called pedigree-based GMDR (PGMDR). Compared to the available method, our proposed method has several major improvements, including allowing for covariate adjustments and being applicable to arbitrary phenotypes, arbitrary pedigree structures, and arbitrary patterns of missing marker genotypes. Our Monte Carlo simulations provide evidence that the PGMDR method is superior in performance to identify epistatic loci compared to the MDR-pedigree disequilibrium test (PDT). Finally, we applied our proposed approach to a genetic data set on tobacco dependence and found a significant interaction between two taste receptor genes (i.e., TAS2R16 and TAS2R38) in affecting nicotine dependence. PMID:18834969
Multifactor Screener in OPEN: Scoring Procedures & Results
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.
Reliability of dose volume constraint inference from clinical data.
Lutz, C M; Møller, D S; Hoffmann, L; Knap, M M; Alber, M
2017-04-21
Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an 'ideal' cohort was generated where the most predictive model was equal to the postulated model. A bootstrap and a Cohort Replication Monte Carlo (CoRepMC) approach were applied to create 1000 equally sized populations each. The cohorts were then analyzed to establish inference frequency distributions. This was applied to nine scenarios for cohort sizes of 102 (1), 500 (2) to 2000 (3) patients (by sampling with replacement) and three postulated DVHP models. The Bootstrap was repeated for a 'non-ideal' cohort, where the most predictive model did not coincide with the postulated model. The Bootstrap produced chaotic results for all models of cohort size 1 for both the ideal and non-ideal cohorts. For cohort size 2 and 3, the distributions for all populations were more concentrated around the postulated DVHP. For the CoRepMC, the inference frequency increased with cohort size and incidence rate. Correct inference rates >[Formula: see text] were only achieved by cohorts with more than 500 patients. Both Bootstrap and CoRepMC indicate that inference of the correct or approximate DVHP for typical cohort sizes is highly uncertain. CoRepMC results were less spurious than Bootstrap results, demonstrating the large influence that randomness in dose-response has on the statistical analysis.
Reliability of dose volume constraint inference from clinical data
NASA Astrophysics Data System (ADS)
Lutz, C. M.; Møller, D. S.; Hoffmann, L.; Knap, M. M.; Alber, M.
2017-04-01
Dose volume histogram points (DVHPs) frequently serve as dose constraints in radiotherapy treatment planning. An experiment was designed to investigate the reliability of DVHP inference from clinical data for multiple cohort sizes and complication incidence rates. The experimental background was radiation pneumonitis in non-small cell lung cancer and the DVHP inference method was based on logistic regression. From 102 NSCLC real-life dose distributions and a postulated DVHP model, an ‘ideal’ cohort was generated where the most predictive model was equal to the postulated model. A bootstrap and a Cohort Replication Monte Carlo (CoRepMC) approach were applied to create 1000 equally sized populations each. The cohorts were then analyzed to establish inference frequency distributions. This was applied to nine scenarios for cohort sizes of 102 (1), 500 (2) to 2000 (3) patients (by sampling with replacement) and three postulated DVHP models. The Bootstrap was repeated for a ‘non-ideal’ cohort, where the most predictive model did not coincide with the postulated model. The Bootstrap produced chaotic results for all models of cohort size 1 for both the ideal and non-ideal cohorts. For cohort size 2 and 3, the distributions for all populations were more concentrated around the postulated DVHP. For the CoRepMC, the inference frequency increased with cohort size and incidence rate. Correct inference rates >85 % were only achieved by cohorts with more than 500 patients. Both Bootstrap and CoRepMC indicate that inference of the correct or approximate DVHP for typical cohort sizes is highly uncertain. CoRepMC results were less spurious than Bootstrap results, demonstrating the large influence that randomness in dose-response has on the statistical analysis.
A simple method for assessing occupational exposure via the one-way random effects model.
Krishnamoorthy, K; Mathew, Thomas; Peng, Jie
2016-11-01
A one-way random effects model is postulated for the log-transformed shift-long personal exposure measurements, where the random effect in the model represents an effect due to the worker. Simple closed-form confidence intervals are proposed for the relevant parameters of interest using the method of variance estimates recovery (MOVER). The performance of the confidence bounds is evaluated and compared with those based on the generalized confidence interval approach. Comparison studies indicate that the proposed MOVER confidence bounds are better than the generalized confidence bounds for the overall mean exposure and an upper percentile of the exposure distribution. The proposed methods are illustrated using a few examples involving industrial hygiene data.
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.
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.
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.
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.
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.
Karayianni, Katerina N; Grimaldi, Keith A; Nikita, Konstantina S; Valavanis, Ioannis K
2015-01-01
This paper aims to enlighten the complex etiology beneath obesity by analysing data from a large nutrigenetics study, in which nutritional and genetic factors associated with obesity were recorded for around two thousand individuals. In our previous work, these data have been analysed using artificial neural network methods, which identified optimised subsets of factors to predict one's obesity status. These methods did not reveal though how the selected factors interact with each other in the obtained predictive models. For that reason, parallel Multifactor Dimensionality Reduction (pMDR) was used here to further analyse the pre-selected subsets of nutrigenetic factors. Within pMDR, predictive models using up to eight factors were constructed, further reducing the input dimensionality, while rules describing the interactive effects of the selected factors were derived. In this way, it was possible to identify specific genetic variations and their interactive effects with particular nutritional factors, which are now under further study.
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.
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.
Machine Learning for Detecting Gene-Gene Interactions
McKinney, Brett A.; Reif, David M.; Ritchie, Marylyn D.; Moore, Jason H.
2011-01-01
Complex interactions among genes and environmental factors are known to play a role in common human disease aetiology. There is a growing body of evidence to suggest that complex interactions are ‘the norm’ and, rather than amounting to a small perturbation to classical Mendelian genetics, interactions may be the predominant effect. Traditional statistical methods are not well suited for detecting such interactions, especially when the data are high dimensional (many attributes or independent variables) or when interactions occur between more than two polymorphisms. In this review, we discuss machine-learning models and algorithms for identifying and characterising susceptibility genes in common, complex, multifactorial human diseases. We focus on the following machine-learning methods that have been used to detect gene-gene interactions: neural networks, cellular automata, random forests, and multifactor dimensionality reduction. We conclude with some ideas about how these methods and others can be integrated into a comprehensive and flexible framework for data mining and knowledge discovery in human genetics. PMID:16722772
A survey about methods dedicated to epistasis detection.
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).
Interrelationships of metal transfer factor under wastewater reuse and soil pollution.
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.
Chemical Carcinogen-Induced Changes in tRNA Metabolism in Human Cells.
1983-11-30
expression of carcinogenesis is postulated. MATERIALS AND METHODS Nucleosldem In urine were resolved and quantitated using reversed-phase high performance...liquid chromatography 8 following clarification on a boronate colun 5 . Quantitation was relative to the creatinine content in random urine specimens 7...Patients Urinary nucleoside excretion has been quantitated for patients with nasopharyngeal carcinoma (NPC) and leukemia, and the results nLn m l
The origin of biological macromolecules on the earth. The hypothesis of inorganic template
NASA Technical Reports Server (NTRS)
Lu, T. S.
1977-01-01
Studies about the origin of life are reviewed. The nonrandom organization of organelles is discussed from a structural and functional point of view. After postulating that the origin of biomacromolecules was not a random event, the paper develops the hypothesis that polypeptides and polynucleotides were formed on an inorganic template. Only information-containing structures can pass natural selection and develop through evolution.
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.
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).
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
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)
Connecting to HPC Systems | High-Performance Computing | NREL
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
Quantum power source: putting in order of a Brownian motion without Maxwell's demon
NASA Astrophysics Data System (ADS)
Aristov, Vitaly V.; Nikulov, A. V.
2003-07-01
The problem of possible violation of the second law of thermodynamics is discussed. It is noted that the task of the well known challenge to the second law called Maxwell's demon is put in order a chaotic perpetual motion and if any ordered Brownian motion exists then the second law can be broken without this hypothetical intelligent entity. The postulate of absolute randomness of any Brownian motion saved the second law in the beginning of the 20th century when it was realized as perpetual motion. This postulate can be proven in the limits of classical mechanics but is not correct according to quantum mechanics. Moreover some enough known quantum phenomena, such as the persistent current at non-zero resistance, are an experimental evidence of the non-chaotic Brownian motion with non-zero average velocity. An experimental observation of a dc quantum power soruce is interperted as evidence of violation of the second law.
Possible Statistics of Two Coupled Random Fields: Application to Passive Scalar
NASA Technical Reports Server (NTRS)
Dubrulle, B.; He, Guo-Wei; Bushnell, Dennis M. (Technical Monitor)
2000-01-01
We use the relativity postulate of scale invariance to derive the similarity transformations between two coupled scale-invariant random elds at different scales. We nd the equations leading to the scaling exponents. This formulation is applied to the case of passive scalars advected i) by a random Gaussian velocity field; and ii) by a turbulent velocity field. In the Gaussian case, we show that the passive scalar increments follow a log-Levy distribution generalizing Kraichnan's solution and, in an appropriate limit, a log-normal distribution. In the turbulent case, we show that when the velocity increments follow a log-Poisson statistics, the passive scalar increments follow a statistics close to log-Poisson. This result explains the experimental observations of Ruiz et al. about the temperature increments.
Ground motion estimation in Delhi from postulated regional and local earthquakes
NASA Astrophysics Data System (ADS)
Mittal, Himanshu; Kumar, Ashok; Kamal
2013-04-01
Ground motions are estimated at 55 sites in Delhi, the capital of India from four postulated earthquakes (three regional M w = 7.5, 8.0, and 8.5 and one local). The procedure consists of (1) synthesis of ground motion at a hard reference site (NDI) and (2) estimation of ground motion at other sites in the city via known transfer functions and application of the random vibration theory. This work provides a more extensive coverage than earlier studies (e.g., Singh et al., Bull Seism Soc Am 92:555-569, 2002; Bansal et al., J Seismol 13:89-105, 2009). The Indian code response spectra corresponding to Delhi (zone IV) are found to be conservative at hard soil sites for all postulated earthquakes but found to be deficient for M w = 8.0 and 8.5 earthquakes at soft soil sites. Spectral acceleration maps at four different natural periods are strongly influenced by the shallow geological and soil conditions. Three pockets of high acceleration values are seen. These pockets seem to coincide with the contacts of (a) Aravalli quartzite and recent Yamuna alluvium (towards the East), (b) Aravalli quartzite and older quaternary alluvium (towards the South), and (c) older quaternary alluvium and recent Yamuna alluvium (towards the North).
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...
Modeling pattern in collections of parameters
Link, W.A.
1999-01-01
Wildlife management is increasingly guided by analyses of large and complex datasets. The description of such datasets often requires a large number of parameters, among which certain patterns might be discernible. For example, one may consider a long-term study producing estimates of annual survival rates; of interest is the question whether these rates have declined through time. Several statistical methods exist for examining pattern in collections of parameters. Here, I argue for the superiority of 'random effects models' in which parameters are regarded as random variables, with distributions governed by 'hyperparameters' describing the patterns of interest. Unfortunately, implementation of random effects models is sometimes difficult. Ultrastructural models, in which the postulated pattern is built into the parameter structure of the original data analysis, are approximations to random effects models. However, this approximation is not completely satisfactory: failure to account for natural variation among parameters can lead to overstatement of the evidence for pattern among parameters. I describe quasi-likelihood methods that can be used to improve the approximation of random effects models by ultrastructural models.
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.
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.
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
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
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).
Lee, Yun; Chen, Fang; Gallego-Giraldo, Lina; Dixon, Richard A.; Voit, Eberhard O.
2011-01-01
The entanglement of lignin polymers with cellulose and hemicellulose in plant cell walls is a major biological barrier to the economically viable production of biofuels from woody biomass. Recent efforts of reducing this recalcitrance with transgenic techniques have been showing promise for ameliorating or even obviating the need for costly pretreatments that are otherwise required to remove lignin from cellulose and hemicelluloses. At the same time, genetic manipulations of lignin biosynthetic enzymes have sometimes yielded unforeseen consequences on lignin composition, thus raising the question of whether the current understanding of the pathway is indeed correct. To address this question systemically, we developed and applied a novel modeling approach that, instead of analyzing the pathway within a single target context, permits a comprehensive, simultaneous investigation of different datasets in wild type and transgenic plants. Specifically, the proposed approach combines static flux-based analysis with a Monte Carlo simulation in which very many randomly chosen sets of parameter values are evaluated against kinetic models of lignin biosynthesis in different stem internodes of wild type and lignin-modified alfalfa plants. In addition to four new postulates that address the reversibility of some key reactions, the modeling effort led to two novel postulates regarding the control of the lignin biosynthetic pathway. The first posits functionally independent pathways toward the synthesis of different lignin monomers, while the second postulate proposes a novel feedforward regulatory mechanism. Subsequent laboratory experiments have identified the signaling molecule salicylic acid as a potential mediator of the postulated control mechanism. Overall, the results demonstrate that mathematical modeling can be a valuable complement to conventional transgenic approaches and that it can provide biological insights that are otherwise difficult to obtain. PMID:21625579
Usable Multi-factor Authentication and Risk-based Authorization
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
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...
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.
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.
Nonlocal dynamics of dissipative phononic fluids
NASA Astrophysics Data System (ADS)
Nemati, Navid; Lee, Yoonkyung E.; Lafarge, Denis; Duclos, Aroune; Fang, Nicholas
2017-06-01
We describe the nonlocal effective properties of a two-dimensional dissipative phononic crystal made by periodic arrays of rigid and motionless cylinders embedded in a viscothermal fluid such as air. The description is based on a nonlocal theory of sound propagation in stationary random fluid/rigid media that was proposed by Lafarge and Nemati [Wave Motion 50, 1016 (2013), 10.1016/j.wavemoti.2013.04.007]. This scheme arises from a deep analogy with electromagnetism and a set of physics-based postulates including, particularly, the action-response procedures, whereby the effective density and bulk modulus are determined. Here, we revisit this approach, and clarify further its founding physical principles through presenting it in a unified formulation together with the two-scale asymptotic homogenization theory that is interpreted as the local limit. Strong evidence is provided to show that the validity of the principles and postulates within the nonlocal theory extends to high-frequency bands, well beyond the long-wavelength regime. In particular, we demonstrate that up to the third Brillouin zone including the Bragg scattering, the complex and dispersive phase velocity of the least-attenuated wave in the phononic crystal which is generated by our nonlocal scheme agrees exactly with that reproduced by a direct approach based on the Bloch theorem and multiple scattering method. In high frequencies, the effective wave and its associated parameters are analyzed by treating the phononic crystal as a random medium.
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
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…
Meta-analysis of laparoscopic versus open repair of perforated peptic ulcer.
Antoniou, Stavros A; Antoniou, George A; Koch, Oliver O; Pointner, Rudolph; Granderath, Frank A
2013-01-01
Laparoscopic treatment of perforated peptic ulcer (PPU) has been introduced as an alternative procedure to open surgery. It has been postulated that the minimally invasive approach involves less operative stress and results in decreased morbidity and mortality. We conducted a meta-analysis of randomized trials to test this hypothesis. Medline, EMBASE, and the Cochrane Central Register of Randomized Trials databases were searched, with no date or language restrictions. Our literature search identified 4 randomized trials, with a cumulative number of 289 patients, that compared the laparoscopic approach with open sutured repair of perforated ulcer. Analysis of outcomes did not favor either approach in terms of morbidity, mortality, and reoperation rate, although odds ratios seemed to consistently support the laparoscopic approach. Results did not determine the comparative efficiency and safety of laparoscopic or open approach for PPU. In view of an increased interest in the laparoscopic approach, further randomized trials are considered essential to determine the relative effectiveness of laparoscopic and open repair of PPU.
Meta-analysis of Laparoscopic Versus Open Repair of Perforated Peptic Ulcer
Antoniou, George A.; Koch, Oliver O.; Pointner, Rudolph; Granderath, Frank A.
2013-01-01
Background and Objectives: Laparoscopic treatment of perforated peptic ulcer (PPU) has been introduced as an alternative procedure to open surgery. It has been postulated that the minimally invasive approach involves less operative stress and results in decreased morbidity and mortality. Methods: We conducted a meta-analysis of randomized trials to test this hypothesis. Medline, EMBASE, and the Cochrane Central Register of Randomized Trials databases were searched, with no date or language restrictions. Results: Our literature search identified 4 randomized trials, with a cumulative number of 289 patients, that compared the laparoscopic approach with open sutured repair of perforated ulcer. Analysis of outcomes did not favor either approach in terms of morbidity, mortality, and reoperation rate, although odds ratios seemed to consistently support the laparoscopic approach. Results did not determine the comparative efficiency and safety of laparoscopic or open approach for PPU. Conclusion: In view of an increased interest in the laparoscopic approach, further randomized trials are considered essential to determine the relative effectiveness of laparoscopic and open repair of PPU. PMID:23743368
Reward and uncertainty in exploration programs
NASA Technical Reports Server (NTRS)
Kaufman, G. M.; Bradley, P. G.
1971-01-01
A set of variables which are crucial to the economic outcome of petroleum exploration are discussed. These are treated as random variables; the values they assume indicate the number of successes that occur in a drilling program and determine, for a particular discovery, the unit production cost and net economic return if that reservoir is developed. In specifying the joint probability law for those variables, extreme and probably unrealistic assumptions are made. In particular, the different random variables are assumed to be independently distributed. Using postulated probability functions and specified parameters, values are generated for selected random variables, such as reservoir size. From this set of values the economic magnitudes of interest, net return and unit production cost are computed. This constitutes a single trial, and the procedure is repeated many times. The resulting histograms approximate the probability density functions of the variables which describe the economic outcomes of an exploratory drilling program.
Rational group decision making: A random field Ising model at T = 0
NASA Astrophysics Data System (ADS)
Galam, Serge
1997-02-01
A modified version of a finite random field Ising ferromagnetic model in an external magnetic field at zero temperature is presented to describe group decision making. Fields may have a non-zero average. A postulate of minimum inter-individual conflicts is assumed. Interactions then produce a group polarization along one very choice which is however randomly selected. A small external social pressure is shown to have a drastic effect on the polarization. Individual bias related to personal backgrounds, cultural values and past experiences are introduced via quenched local competing fields. They are shown to be instrumental in generating a larger spectrum of collective new choices beyond initial ones. In particular, compromise is found to results from the existence of individual competing bias. Conflict is shown to weaken group polarization. The model yields new psychosociological insights about consensus and compromise in groups.
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…
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
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....
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
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...
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…
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…
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…
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…
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…
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.
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 ...
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 ...
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…
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.…
Existence and Optimality Conditions for Risk-Averse PDE-Constrained Optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kouri, Drew Philip; Surowiec, Thomas M.
Uncertainty is ubiquitous in virtually all engineering applications, and, for such problems, it is inadequate to simulate the underlying physics without quantifying the uncertainty in unknown or random inputs, boundary and initial conditions, and modeling assumptions. Here in this paper, we introduce a general framework for analyzing risk-averse optimization problems constrained by partial differential equations (PDEs). In particular, we postulate conditions on the random variable objective function as well as the PDE solution that guarantee existence of minimizers. Furthermore, we derive optimality conditions and apply our results to the control of an environmental contaminant. Lastly, we introduce a new riskmore » measure, called the conditional entropic risk, that fuses desirable properties from both the conditional value-at-risk and the entropic risk measures.« less
Existence and Optimality Conditions for Risk-Averse PDE-Constrained Optimization
Kouri, Drew Philip; Surowiec, Thomas M.
2018-06-05
Uncertainty is ubiquitous in virtually all engineering applications, and, for such problems, it is inadequate to simulate the underlying physics without quantifying the uncertainty in unknown or random inputs, boundary and initial conditions, and modeling assumptions. Here in this paper, we introduce a general framework for analyzing risk-averse optimization problems constrained by partial differential equations (PDEs). In particular, we postulate conditions on the random variable objective function as well as the PDE solution that guarantee existence of minimizers. Furthermore, we derive optimality conditions and apply our results to the control of an environmental contaminant. Lastly, we introduce a new riskmore » measure, called the conditional entropic risk, that fuses desirable properties from both the conditional value-at-risk and the entropic risk measures.« less
Bush, Sean P; Mooy, Graham G; Phan, Tammy H
2014-06-01
We report 2 cases of catastrophic ischemic stroke after Crotalidae polyvalent immune Fab (ovine)-treated rattlesnake envenomation, 1 fatal and the other resulting in significant permanent disability. It is possible these serious adverse events may have been related to venom factor(s), an interaction between venom and antivenom, occult patient blood dyscrasia, or to random unrelated events. We present the rationale for each possibility, and submit the experiences to elicit alternate postulation and communication of similar presentations. Copyright © 2014 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Evolutionary constraints and the neutral theory. [mutation-caused nucleotide substitutions in DNA
NASA Technical Reports Server (NTRS)
Jukes, T. H.; Kimura, M.
1984-01-01
The neutral theory of molecular evolution postulates that nucleotide substitutions inherently take place in DNA as a result of point mutations followed by random genetic drift. In the absence of selective constraints, the substitution rate reaches the maximum value set by the mutation rate. The rate in globin pseudogenes is about 5 x 10 to the -9th substitutions per site per year in mammals. Rates slower than this indicate the presence of constraints imposed by negative (natural) selection, which rejects and discards deleterious mutations.
Heterogeneity in the Effect of Common Shocks on Healthcare Expenditure Growth.
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.
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.
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…
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…
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…
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].
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.
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.
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
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
Li, Yan; Ma, Hongli; Zhang, Yuehui; Kuang, Hongying; Ng, Ernest Hung Yu; Hou, Lihui; Wu, Xiaoke
2013-07-18
Insulin resistance and hyperinsulinemia play a key role in the pathogenesis of polycystic ovary syndrome (PCOS), which is characterized by hyperandrogenism, ovulatory dysfunction, and presence of polycystic ovaries on pelvic scanning. Insulin resistance is significantly associated with the long-term risks of metabolic syndrome and cardiovascular disease. Berberine has effects on insulin resistance but its use in women with PCOS has not been fully investigated. In this paper, we present a research design evaluating the effects of berberine on insulin resistance in women with PCOS. This is a multicenter, randomized, placebo-controlled and double-blind trial. A total of 120 patients will be enrolled in this study and will be randomized into two groups. Berberine or placebo will be taken orally for 12 weeks. The primary outcome is the whole body insulin action assessed with the hyperinsulinemic-euglycemic clamp. We postulate that women with PCOS will have improved insulin resistance following berberine administration. This study is registered at ClinicalTrials.gov, NCT01138930.
The Correlation between Leadership Style and Leader Power
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
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
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
Modeling and Predicting the Stress Relaxation of Composites with Short and Randomly Oriented Fibers
Obaid, Numaira; Sain, Mohini
2017-01-01
The addition of short fibers has been experimentally observed to slow the stress relaxation of viscoelastic polymers, producing a change in the relaxation time constant. Our recent study attributed this effect of fibers on stress relaxation behavior to the interfacial shear stress transfer at the fiber-matrix interface. This model explained the effect of fiber addition on stress relaxation without the need to postulate structural changes at the interface. In our previous study, we developed an analytical model for the effect of fully aligned short fibers, and the model predictions were successfully compared to finite element simulations. However, in most industrial applications of short-fiber composites, fibers are not aligned, and hence it is necessary to examine the time dependence of viscoelastic polymers containing randomly oriented short fibers. In this study, we propose an analytical model to predict the stress relaxation behavior of short-fiber composites where the fibers are randomly oriented. The model predictions were compared to results obtained from Monte Carlo finite element simulations, and good agreement between the two was observed. The analytical model provides an excellent tool to accurately predict the stress relaxation behavior of randomly oriented short-fiber composites. PMID:29053601
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.
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.
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
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
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
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.
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
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.
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.
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
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
Nurse executive transformational leadership found in participative organizations.
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.
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.
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 Simple Lab Exercise Demonstrating Koch's Postulates.
ERIC Educational Resources Information Center
Fulton, Michael M.
1981-01-01
Describes a laboratory exercise which applies Koch's Postulates to a plant disease, bacterial speck. Includes an explanation of Koch's Postulate, list of equipment needed, advance preparation, outline of the three-week activity, and variations of the laboratory exercise. (DS)
Actor-network Procedures: Modeling Multi-factor Authentication, Device Pairing, Social Interactions
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
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...
Case management to reduce risk of cardiovascular disease in a county health care system.
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.
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.
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.
NASA Astrophysics Data System (ADS)
Avendaño-Valencia, Luis David; Fassois, Spilios D.
2017-07-01
The study focuses on vibration response based health monitoring for an operating wind turbine, which features time-dependent dynamics under environmental and operational uncertainty. A Gaussian Mixture Model Random Coefficient (GMM-RC) model based Structural Health Monitoring framework postulated in a companion paper is adopted and assessed. The assessment is based on vibration response signals obtained from a simulated offshore 5 MW wind turbine. The non-stationarity in the vibration signals originates from the continually evolving, due to blade rotation, inertial properties, as well as the wind characteristics, while uncertainty is introduced by random variations of the wind speed within the range of 10-20 m/s. Monte Carlo simulations are performed using six distinct structural states, including the healthy state and five types of damage/fault in the tower, the blades, and the transmission, with each one of them characterized by four distinct levels. Random vibration response modeling and damage diagnosis are illustrated, along with pertinent comparisons with state-of-the-art diagnosis methods. The results demonstrate consistently good performance of the GMM-RC model based framework, offering significant performance improvements over state-of-the-art methods. Most damage types and levels are shown to be properly diagnosed using a single vibration sensor.
An Economical Multifactor within-Subject Design Robust against Trend and Carryover Effects.
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.-/195 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].
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.
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.
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.
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.
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
NASA Astrophysics Data System (ADS)
Rozi; Rahayu, K.; Daruti, D. N.; Stella, M. S. P.
2018-04-01
This study aims to determine the bacterial pathogens that cause disease of the gourami in Blitar (East Java) and Yogyakarta (Central Java), Indonesia. A total of 50 fish samples taken randomly gourami in pond farmers in seventh different locations. There were 18 isolates were isolated and then test Koch’s postulates were injected 0.1 ml/fish intraperitoneally to gourami. Characterization is done by using the biochemical tests. Pathogenicity test carried out on 3 isolates of Aeromonas spp. with intraperitoneal injection at a dose of 104-108 CFU/fish, the value of Lethal Dosage 50 (LD50) using the method Dragstedt Behrens. After the treatment, spleen and kidney samples were processed for histopathological analysis. The all of identified bacteria were 5 isolates Aeromonas hydrophila. Isolates of A. hydrophila in a row AH3 was virulen to gourami with LD50 (4.53 x 106 CFU/fish), while isolate AH4 and AH5 (2.903 x 108, 1.319 x 109 CFU/fish) not be avirulen. Koch’s postulates; 3 isolates are pathogenic with mortality of 40-100 % and 2 are non-pathogenic isolates with a mortality of 0 %. Clinically; ulcers, haemorhagic at the base of the fins, body, mouth and exophthalmia. Histopathologically indecated spleen necrosis, piknosis, necrosis and inflammatory cells in kidney.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-20
... the ``Regulatory Guides'' collection of the NRC's Library at http://www.nrc.gov/reading-rm/doc... NUCLEAR REGULATORY COMMISSION [NRC-2011-0152] Evaluations of Explosions Postulated To Occur at..., ``Evaluations of Explosions Postulated to Occur at Nearby Facilities and on Transportation Routes Near Nuclear...
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.
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.
ERIC Educational Resources Information Center
Abiko, Seiya
2005-01-01
Einstein, who had already developed the light-quantum theory, knew the inadequacy of Maxwell's theory in the microscopic sphere. Therefore, in writing his paper on special relativity, he had to set up the light-velocity postulate independently of the relativity postulate in order to make the electromagnetic foundation of physics compatible with…
A Theory of Vocational Development for Women.
ERIC Educational Resources Information Center
Zytowski, Donald G.
In postulate I, the modal life role for women is described as that of the homemaker. Postulate II proposes that the nature of the woman's role is not static, ultimately bearing no distinction from that of men. Postulate III states that the role of women is orderly and developmental, divisible into major segments according to the major task in…
1975-10-08
m AD-A020 796 A POSTULATED MECHANISM THAT LEADS TO MATERIALIZATION AND DEMATERIALIZATION OF MATTER AND TO ANTIGRAVITY Thomas E. Bearden Army...TITLE fand Subtlll») A POSTULATED MECHANISM THAT LEADS TO MATERIALIZATION AND DEMATERIALIZATION OF MATTER AND TO ANTIGRAVITY S. TYPE OF REPORT... Antigravity 1 Three-dimensional space Photon Orthogonal frames i I
Power of data mining methods to detect genetic associations and interactions.
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.
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.
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.
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.
How multiple factors control evapotranspiration in North America evergreen needleleaf forests.
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.
Seppecher, P.
2015-01-01
In order to found continuum mechanics, two different postulations have been used. The first, introduced by Lagrange and Piola, starts by postulating how the work expended by internal interactions in a body depends on the virtual velocity field and its gradients. Then, by using the divergence theorem, a representation theorem is found for the volume and contact interactions which can be exerted at the boundary of the considered body. This method assumes an a priori notion of internal work, regards stress tensors as dual of virtual displacements and their gradients, deduces the concept of contact interactions and produces their representation in terms of stresses using integration by parts. The second method, conceived by Cauchy and based on the celebrated tetrahedron argument, starts by postulating the type of contact interactions which can be exerted on the boundary of every (suitably) regular part of a body. Then it proceeds by proving the existence of stress tensors from a balance-type postulate. In this paper, we review some relevant literature on the subject, discussing how the two postulations can be reconciled in the case of higher gradient theories. Finally, we underline the importance of the concept of contact surface, edge and wedge s-order forces. PMID:26730215
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.
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.
Detailed Balance of Thermalization Dynamics in Rydberg-Atom Quantum Simulators.
Kim, Hyosub; Park, YeJe; Kim, Kyungtae; Sim, H-S; Ahn, Jaewook
2018-05-04
Dynamics of large complex systems, such as relaxation towards equilibrium in classical statistical mechanics, often obeys a master equation that captures essential information from the complexities. Here, we find that thermalization of an isolated many-body quantum state can be described by a master equation. We observe sudden quench dynamics of quantum Ising-like models implemented in our quantum simulator, defect-free single-atom tweezers in conjunction with Rydberg-atom interaction. Saturation of their local observables, a thermalization signature, obeys a master equation experimentally constructed by monitoring the occupation probabilities of prequench states and imposing the principle of the detailed balance. Our experiment agrees with theories and demonstrates the detailed balance in a thermalization dynamics that does not require coupling to baths or postulated randomness.
Detailed Balance of Thermalization Dynamics in Rydberg-Atom Quantum Simulators
NASA Astrophysics Data System (ADS)
Kim, Hyosub; Park, YeJe; Kim, Kyungtae; Sim, H.-S.; Ahn, Jaewook
2018-05-01
Dynamics of large complex systems, such as relaxation towards equilibrium in classical statistical mechanics, often obeys a master equation that captures essential information from the complexities. Here, we find that thermalization of an isolated many-body quantum state can be described by a master equation. We observe sudden quench dynamics of quantum Ising-like models implemented in our quantum simulator, defect-free single-atom tweezers in conjunction with Rydberg-atom interaction. Saturation of their local observables, a thermalization signature, obeys a master equation experimentally constructed by monitoring the occupation probabilities of prequench states and imposing the principle of the detailed balance. Our experiment agrees with theories and demonstrates the detailed balance in a thermalization dynamics that does not require coupling to baths or postulated randomness.
Modelling the Somatic Electrical Response of Hippocampal Pyramidal Neurons
1989-09-01
postulated in the present study, and b) an approximation of the electrotonic structure of the cell that is derived in this thesis , based on data for the...the literature or postulated in the present study, and b) an approximation of the electrotonic structure of the cell that is derived in this thesis ...postulated in the present study, and b) an approximation of the electrotonic structure of the cell that is derived in this thesis , based on data for
On the determinants of the conjunction fallacy: probability versus inductive confirmation.
Tentori, Katya; Crupi, Vincenzo; Russo, Selena
2013-02-01
Major recent interpretations of the conjunction fallacy postulate that people assess the probability of a conjunction according to (non-normative) averaging rules as applied to the constituents' probabilities or represent the conjunction fallacy as an effect of random error in the judgment process. In the present contribution, we contrast such accounts with a different reading of the phenomenon based on the notion of inductive confirmation as defined by contemporary Bayesian theorists. Averaging rule hypotheses along with the random error model and many other existing proposals are shown to all imply that conjunction fallacy rates would rise as the perceived probability of the added conjunct does. By contrast, our account predicts that the conjunction fallacy depends on the added conjunct being perceived as inductively confirmed. Four studies are reported in which the judged probability versus confirmation of the added conjunct have been systematically manipulated and dissociated. The results consistently favor a confirmation-theoretic account of the conjunction fallacy against competing views. Our proposal is also discussed in connection with related issues in the study of human inductive reasoning. 2013 APA, all rights reserved
Coverage maximization under resource constraints using a nonuniform proliferating random walk.
Saha, Sudipta; Ganguly, Niloy
2013-02-01
Information management services on networks, such as search and dissemination, play a key role in any large-scale distributed system. One of the most desirable features of these services is the maximization of the coverage, i.e., the number of distinctly visited nodes under constraints of network resources as well as time. However, redundant visits of nodes by different message packets (modeled, e.g., as walkers) initiated by the underlying algorithms for these services cause wastage of network resources. In this work, using results from analytical studies done in the past on a K-random-walk-based algorithm, we identify that redundancy quickly increases with an increase in the density of the walkers. Based on this postulate, we design a very simple distributed algorithm which dynamically estimates the density of the walkers and thereby carefully proliferates walkers in sparse regions. We use extensive computer simulations to test our algorithm in various kinds of network topologies whereby we find it to be performing particularly well in networks that are highly clustered as well as sparse.
Schwartz, M; Waltenbaugh, C; Dorf, M; Cesla, R; Sela, M; Benacerraf, B
1976-01-01
The ability of mice bearing the H-2S haplotype to develop helper responses to the random copolymer of Glu,Ala while they developed suppressor responses to the terpolymer of Glu,Ala,Tyr suggested the crucial role of tyrosine in these peptides. On the basis of various considerations, it was postulated that many of the tyrosine residues in Glu,Ala,Tyr would be localized at the NH2-terminal end of the molecule. To verify this hypothesis, a block terpolymer composed of a short sequence of homopolymer tyrosine covalently bound to the random copolymer of Glu,Ala was synthesized. The present studies, using this block terpolymer, demonstrated that the chemical determinants stimulating helper and suppressor responses are distinct and can be present simultaneously in the same molecule. Thus, addition of COOH-terminal tyrosine residues to the Glu,Ala polypeptide converted this immunogenic molecule to an immunosuppressive molecule in mice bearing the H-2S haplotype. The mechanism by which these short sequences of tyrosine influence H-2-linked immune responses remains to be determined. PMID:60762
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.
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.
Information-Theoretic Metrics for Visualizing Gene-Environment Interactions
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
Classical and special relativity in four steps
NASA Astrophysics Data System (ADS)
Browne, K. M.
2018-03-01
The most fundamental and pedagogically useful path to the space-time transformations of both classical and special relativity is to postulate the principle of relativity, derive the generalised or Ignatowsky transformation which contains both, then apply two different second postulates that give either the Galilean or Lorentz transformation. What is new here is (a) a simple two-step derivation of the Ignatowsky transformation, (b) a second postulate of universal time which yields the Galilean transformation, and (c) a different second postulate of finite universal lightspeed to give the Lorentz transformation using a simple Ignatowsky transformation of a light wave. This method demonstrates that the fundamental difference between Galilean and Lorentz transformations is not that lightspeed is universal (which is true for both) but whether the model requires lightspeed to be infinite or finite (as once mentioned by Einstein).
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.
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.
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].
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.
Stem cell identity and template DNA strand segregation.
Tajbakhsh, Shahragim
2008-12-01
The quest for stem cell properties to distinguish their identity from that of committed daughters has led to a re-investigation of the notion that DNA strands are not equivalent, and 'immortal' DNA strands are retained in stem cells whereas newly replicated DNA strands segregate to the differentiating daughter cell during mitosis. Whether this process occurs only in stem cells, and also in all tissues, remains unclear. That individual chromosomes can be also partitioned non-randomly raises the question if this phenomenon is related to the immortal DNA hypothesis, and it underscores the need for high-resolution techniques to observe these events empirically. Although initially postulated as a mechanism to avoid DNA replication errors, alternative views including epigenetic regulation and sister chromatid silencing may provide insights into this process.
Age differences in goals: implications for health promotion.
Zhang, Xin; Fung, Helene; Ching, Bob Ho-hong
2009-05-01
Socioemotional selectivity theory postulates that, as people age, they prioritize emotionally meaningful goals. This study investigated whether these age differences in goals are reflected in how younger (aged 18-36, n = 111) and older adults (aged 62-86, n = 104) evaluated, remembered information from and were persuaded by health messages. Participants were randomly assigned to read health pamphlets with identical factual information but emphasizing emotional or non-emotional goals. Findings showed that health messages that emphasized emotional goals, but not those that emphasized future-oriented or neutral goals, were better remembered, were evaluated more positively and led to greater behavioral changes among older adults, but not younger adults. These findings suggest that health messages targeting older adults may be more effective if they are framed in ways that emphasize love and caring.
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].
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
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
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.
Simulations of radiation pressure experiments narrow down the energy and momentum of light in matter
NASA Astrophysics Data System (ADS)
Bethune-Waddell, Max; Chau, Kenneth J.
2015-12-01
Consensus on a single electrodynamic theory has yet to be reached. Discord was seeded over a century ago when Abraham and Minkowski proposed different forms of electromagnetic momentum density and has since expanded in scope with the gradual introduction of other forms of momentum and force densities. Although degenerate sets of electrodynamic postulates can be fashioned to comply with global energy and momentum conservation, hope remains to isolate a single theory based on detailed comparison between force density predictions and radiation pressure experiments. This comparison is two-fold challenging because there are just a handful of quantitative radiation pressure measurements over the past century and the solutions developed from different postulates, which consist of approximate expressions and inferential deductions, are scattered throughout the literature. For these reasons, it is appropriate to conduct a consolidated and comprehensive re-analysis of past experiments under the assumption that the momentum and energy of light in matter are degenerate. We create a combined electrodynamic/fluid dynamic simulation testbed that uses five historically significant sets of electrodynamic postulates, including those by Abraham and Minkowski, to model radiation pressure under diverse configurations with minimal assumptions. This leads to new interpretations of landmark investigations of light momentum, including the Balazs thought experiment, the Jones-Richards and Jones-Leslie measurements of radiation pressure on submerged mirrors, observations of laser-deformed fluid surfaces, and experiments on optical trapping and tractor beaming of dielectric particles. We discuss the merits and demerits of each set of postulates when compared to available experimental evidence and fundamental conservation laws. Of the five sets of postulates, the Abraham and Einstein-Laub postulates provide the greatest consistency with observations and the most physically plausible descriptions of electrodynamic interactions. Force density predictions made by these two postulates are unique under many conditions and their experimental isolation is potentially within reach.
2012-01-01
Background Time-course gene expression data such as yeast cell cycle data may be periodically expressed. To cluster such data, currently used Fourier series approximations of periodic gene expressions have been found not to be sufficiently adequate to model the complexity of the time-course data, partly due to their ignoring the dependence between the expression measurements over time and the correlation among gene expression profiles. We further investigate the advantages and limitations of available models in the literature and propose a new mixture model with autoregressive random effects of the first order for the clustering of time-course gene-expression profiles. Some simulations and real examples are given to demonstrate the usefulness of the proposed models. Results We illustrate the applicability of our new model using synthetic and real time-course datasets. We show that our model outperforms existing models to provide more reliable and robust clustering of time-course data. Our model provides superior results when genetic profiles are correlated. It also gives comparable results when the correlation between the gene profiles is weak. In the applications to real time-course data, relevant clusters of coregulated genes are obtained, which are supported by gene-function annotation databases. Conclusions Our new model under our extension of the EMMIX-WIRE procedure is more reliable and robust for clustering time-course data because it adopts a random effects model that allows for the correlation among observations at different time points. It postulates gene-specific random effects with an autocorrelation variance structure that models coregulation within the clusters. The developed R package is flexible in its specification of the random effects through user-input parameters that enables improved modelling and consequent clustering of time-course data. PMID:23151154
NASA Astrophysics Data System (ADS)
Longoria, Raul Gilberto
An experimental apparatus has been developed which can be used to generate a general time-dependent planar flow across a cylinder. A mass of water enclosed with no free surface within a square cross-section tank and two spring pre-loaded pistons is oscillated using a hydraulic actuator. A circular cylinder is suspended horizontally in the tank by two X-Y force transducers used to simultaneously measure the total in-line and transverse forces. Fluid motion is measured using a differential pressure transducer for instantaneous acceleration and an LVDT for displacement. This investigation provides measurement of forces on cylinders subjected to planar fluid flow velocity with a time (and frequency) dependence which more accurately represent the random conditions encountered in a natural ocean environment. The use of the same apparatus for both sinusoidal and random experiments provides a quantified assessment of the applicability of sinusoidal planar oscillatory flow data in offshore structure design methods. The drag and inertia coefficients for a Morison equation representation of the inline force are presented for both sinusoidal and random flow. Comparison of the sinusoidal results is favorable with those of previous investigations. The results from random experiments illustrates the difference in the force mechanism by contrasting the force transfer coefficients for the inline and transverse forces. It is found that application of sinusoidal results to random hydrodynamic inline force prediction using the Morison equation wrongly weighs the drag and inertia components, and the transverse force is overpredicted. The use of random planar oscillatory flow in the laboratory, contrasted with sinusoidal planar oscillatory flow, quantifies the accepted belief that the force transfer coefficients from sinusoidal flow experiments are conservative for prediction of forces on cylindrical structures subjected to random sea waves and the ensuing forces. Further analysis of data is conducted in the frequency domain to illustrate models used for predicting the power spectral density of the inline force including a nonlinear describing function method. It is postulated that the large-scale vortex activity prominent in sinusoidal oscillatory flow is subdued in random flow conditions.
Testing statistical self-similarity in the topology of river networks
Troutman, Brent M.; Mantilla, Ricardo; Gupta, Vijay K.
2010-01-01
Recent work has demonstrated that the topological properties of real river networks deviate significantly from predictions of Shreve's random model. At the same time the property of mean self-similarity postulated by Tokunaga's model is well supported by data. Recently, a new class of network model called random self-similar networks (RSN) that combines self-similarity and randomness has been introduced to replicate important topological features observed in real river networks. We investigate if the hypothesis of statistical self-similarity in the RSN model is supported by data on a set of 30 basins located across the continental United States that encompass a wide range of hydroclimatic variability. We demonstrate that the generators of the RSN model obey a geometric distribution, and self-similarity holds in a statistical sense in 26 of these 30 basins. The parameters describing the distribution of interior and exterior generators are tested to be statistically different and the difference is shown to produce the well-known Hack's law. The inter-basin variability of RSN parameters is found to be statistically significant. We also test generator dependence on two climatic indices, mean annual precipitation and radiative index of dryness. Some indication of climatic influence on the generators is detected, but this influence is not statistically significant with the sample size available. Finally, two key applications of the RSN model to hydrology and geomorphology are briefly discussed.
Closed system of coupling effects in generalized thermo-elastoplasticity
NASA Astrophysics Data System (ADS)
Śloderbach, Z.
2016-05-01
In this paper, the field equations of the generalized coupled thermoplasticity theory are derived using the postulates of classical thermodynamics of irreversible processses. Using the Legendre transformations two new thermodynamics potentials P and S depending upon internal thermodynamic forces Π are introduced. The most general form for all the thermodynamics potentials are assumed instead of the usually used additive form. Due to this assumption, it is possible to describe all the effects of thermomechanical couples and also the elastic-plastic coupling effects observed in such materials as rocks, soils, concretes and in some metalic materials. In this paper not only the usual postulate of existence of a dissipation qupotential (the Gyarmati postulate) is used to derive the velocity equation. The plastic flow constitutive equations have the character of non-associated flow laws even when the Gyarmati postulate is assumed. In general formulation, the plastic strain rate tensor is normal to the surface of the generalized function of plastic flow defined in the the space of internal thermodynamic forces Π but is not normal to the yield surface. However, in general formulation and after the use the Gyarmati postulate, the direction of the sum of the plastic strain rate tensor and the coupled elastic strain rate tensor is normal to the yield surface.
Koch's postulates, carnivorous cows, and tuberculosis today.
Tabrah, Frank L
2011-07-01
With Koch's announcement in 1882 of his work with the tubercle bacillus, his famous postulates launched the rational world of infectious disease and an abrupt social change--strict patient isolation. The postulates, so successful at their inception, soon began to show some problems, particularly with cholera, which clearly violated some of Koch's requirements. Subsequent studies of other diseases and the discovery of entirely new ones have so altered and expanded the original postulates that they now are little but a precious touch of history. The present additions and replacements of the original concepts are skillful changes that several authors have devised to introduce new order into understanding complex viral and prion diseases. In 1988, this knowledge, with the totally rational response of the British population and its cattle industry, was critical in promptly blocking the threatened epidemic of human prion disease. In contrast, the recent upsurge of tuberculosis (TB) in the worldwide AIDS epidemic in developing countries, and the sudden increase in metabolic syndrome in wealthy ones, suggests the need for focused sociobiologic research seeking ways to affect the damaging lifestyle behavior of many less educated populations in both settings. The world awaits an equivalent of Koch's Postulates in sociobiology to explain and possibly avert large self-destructive behaviors.
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.
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.
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.
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
Risk factors associated with sporadic salmonellosis in adults: a case-control study.
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.
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.
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.;
2012-01-01
Diverse vulnerabilities of Bangladesh's agricultural sector in 16 sub-regions are assessed using experiments designed to investigate climate impact factors in isolation and in combination. Climate information from a suite of global climate models (GCMs) is used to drive models assessing the agricultural impact of changes in temperature, precipitation, carbon dioxide concentrations, river floods, and sea level rise for the 2040-2069 period in comparison to a historical baseline. Using the multi-factor impacts analysis framework developed in Yu et al. (2010), this study provides new sub-regional vulnerability analyses and quantifies key uncertainties in climate and production. Rice (aman, boro, and aus seasons) and wheat production are simulated in each sub-region using the biophysical Crop Environment REsource Synthesis (CERES) models. These simulations are then combined with the MIKE BASIN hydrologic model for river floods in the Ganges-Brahmaputra-Meghna (GBM) Basins, and the MIKE21Two-Dimensional Estuary Model to determine coastal inundation under conditions of higher mean sea level. The impacts of each factor depend on GCM configurations, emissions pathways, sub-regions, and particular seasons and crops. Temperature increases generally reduce production across all scenarios. Precipitation changes can have either a positive or a negative impact, with a high degree of uncertainty across GCMs. Carbon dioxide impacts on crop production are positive and depend on the emissions pathway. Increasing river flood areas reduce production in affected sub-regions. Precipitation uncertainties from different GCMs and emissions scenarios are reduced when integrated across the large GBM Basins' hydrology. Agriculture in Southern Bangladesh is severely affected by sea level rise even when cyclonic surges are not fully considered, with impacts increasing under the higher emissions scenario.
The Multifactor Measure of Performance: Its Development, Norming, and Validation
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
A Conceptual Derivation of Einstein's Postulates of Special Relativity.
ERIC Educational Resources Information Center
Bearden, Thomas E.
This document presents a discussion and conceptual derivation of Einstein's postulates of special relativity. The perceptron approach appears to be a fundamentally new manner of regarding physical phenomena and it is hoped that physicists will interest themselves in the concept. (Author)
PPCM: Combing multiple classifiers to improve protein-protein interaction prediction
Yao, Jianzhuang; Guo, Hong; Yang, Xiaohan
2015-08-01
Determining protein-protein interaction (PPI) in biological systems is of considerable importance, and prediction of PPI has become a popular research area. Although different classifiers have been developed for PPI prediction, no single classifier seems to be able to predict PPI with high confidence. We postulated that by combining individual classifiers the accuracy of PPI prediction could be improved. We developed a method called protein-protein interaction prediction classifiers merger (PPCM), and this method combines output from two PPI prediction tools, GO2PPI and Phyloprof, using Random Forests algorithm. The performance of PPCM was tested by area under the curve (AUC) using anmore » assembled Gold Standard database that contains both positive and negative PPI pairs. Our AUC test showed that PPCM significantly improved the PPI prediction accuracy over the corresponding individual classifiers. We found that additional classifiers incorporated into PPCM could lead to further improvement in the PPI prediction accuracy. Furthermore, cross species PPCM could achieve competitive and even better prediction accuracy compared to the single species PPCM. This study established a robust pipeline for PPI prediction by integrating multiple classifiers using Random Forests algorithm. Ultimately, this pipeline will be useful for predicting PPI in nonmodel species.« less
Safely Teaching Koch's Postulates on the Causation of Infectious Disease.
ERIC Educational Resources Information Center
Stewart, Peter R.
1990-01-01
Described is an activity in which the interactions between a parasite and its host may be demonstrated using the relationship between yogurt and two species of bacteria. Background information on Koch's postulates is provided. Materials, laboratory procedures, and results are discussed. (CW)
Uniqueness of the Isotropic Frame and Usefulness of the Lorentz Transformation
NASA Astrophysics Data System (ADS)
Choi, Yang-Ho
2018-05-01
According to the postulates of the special theory of relativity (STR), physical quantities such as proper times and Doppler shifts can be obtained from any inertial frame by regarding it as isotropic. Nonetheless many inconsistencies arise from the postulates, as shown in this paper. However, there are numerous experimental results that agree with the predictions of STR. It is explained why they are accurate despite the inconsistencies. The Lorentz transformation (LT), unless subject to the postulates of STR, may be a useful method to approach physics problems. As an example to show the usefulness of LT, the problem of the generalized Sagnac effect is solved by utilizing it.
Application of a postulate based control theory for an artificial arm
NASA Technical Reports Server (NTRS)
Jacobsen, S. C.; Jerard, R. B.
1975-01-01
The biocontroller, remnant of the natural arm, and feedback elements must be considered in designing a controller for an above elbow artificial arm for amputees. This fundamental postulate is used to derive equations for developing the controller, which is shown in block diagrams.
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.
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
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.
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.
Effects of Cooperative, Competitive, and Individualized Goal Structures on Learning Outcomes.
ERIC Educational Resources Information Center
Johnson, David W.; Johnson, Roger T.
A theoretical orientation to three goal structures (cooperation, competition, and individualization) is postulated, based upon Deutsch's extension of Lewin's theory of motivation. Lewin postulated that a state of tension within a person motivates movement toward the accomplishment of desired goals; a goal structure specifies the type of…
Interdisciplinarity in Swiss Schools: A Difficult Step into the Future
ERIC Educational Resources Information Center
Ghisla, Gianni; Bausch, Luca; Bonoli, Lorenzo
2010-01-01
Multi- and interdisciplinary education is a major postulate in the Swiss school system and has considerable weight in educational programs and learning objectives, both in compulsory school and at the upper secondary school level. However, materializing this postulate still poses problems at the political and institutional level, where the…
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
Shibre, Teshome; Alem, Atalay; Abdulahi, Abdulreshid; Araya, Mesfin; Beyero, Teferra; Medhin, Girmay; Deyassa, Negusse; Negash, Alemayehu; Nigatu, Alemayehu; Kebede, Derege
2010-01-01
Various infectious agents, such as Toxoplasma gondii, have been hypothesized to be potentially relevant etiological factors in the onset of some cases of schizophrenia. We conducted a randomized, double-blind, placebo-controlled treatment trial in an attempt to explore the hypothesis that the symptoms of schizophrenia may be related to infection of the central nervous system with toxoplasma gondii. Systematically selected patients with ongoing and at least moderately severe schizophrenia from Butajira, in rural Ethiopia, were randomly allocated to trimethoprim or placebo, which were added on to participants' regular antipsychotic treatments. Trial treatments were given for 6 months. The Positive and Negative Syndrome Scale (PANSS) was used to assess outcome. Ninety-one patients were included in the study, with 80 cases (87.9%) positive for T. gondii immunoglobulin G antibody. Seventy-nine subjects (87.0%) completed the trial. The mean age of subjects was 35.3 (SD = 8.0) years, with a mean duration of illness of 13.2 (SD = 6.7) years. Both treatment groups showed significant reduction in the overall PANSS score with no significant between-group difference. In this sample of patients with chronic schizophrenia, trimethoprim used as adjuvant treatment is not superior to placebo. However, it is not possible to draw firm conclusion regarding the etiological role of toxoplasmosis on schizophrenia based on this study because the timing and the postulated mechanisms through which toxoplasmosis produces schizophrenia are variable. PMID:19193743
An Inexpensive and Safe Experiment to Demonstrate Koch's Postulates Using Citrus Fruit
ERIC Educational Resources Information Center
Jakobi, Steven
2010-01-01
Citrus fruit (oranges, tangerines, grapefruit or lemons) purchased in a grocery store can be experimentally infected with readily-available sources of "Penicillium digitatum" to demonstrate the four basic steps of Koch's postulates, also known as proof of pathogenicity. The mould is isolated from naturally-infected citrus fruit into pure culture…
ERIC Educational Resources Information Center
Scala, Alfred A.
2004-01-01
The underlying ideas of the Polanyi principle and Hammond's postulate in relation to the simple free halogenation reactions and their selectivity and thermodynamics is presented. The results indicate that the chlorine atom exhibits a slightly less selectivity in the liquid phase as compared to in the gas phase.
The Emergence of a Root Metaphor in Modern Physics: Max Planck's "Quantum" Metaphor.
ERIC Educational Resources Information Center
Johnson-Sheehan, Richard D.
1997-01-01
Uses metaphorical analysis to determine whether or not Max Planck invented the quantum postulate. Demonstrates how metaphorical analysis can be used to analyze the rhetoric of revolutionary texts in science. Concludes that, in his original 1900 quantum paper, Planck considered the quantum postulate to be important, but not revolutionary. (PA)
The Application of Mechanics to Geometry. Popular Lectures in Mathematics.
ERIC Educational Resources Information Center
Kogan, B. Yu
Presented in this translation are three chapters. Chapter I discusses the composition of forces and several theorems of geometry are proved using the fundamental concepts and certain laws of statics. Chapter II discusses the perpetual motion postulate; several geometric theorems are proved using the postulate that perpetual motion is impossible.…
Life on Mars? II. Physical restrictions
NASA Technical Reports Server (NTRS)
Mancinelli, R. L.; Banin, A.
1995-01-01
The primary physical factors important to life's evolution on a planet include its temperature, pressure and radiation regimes. Temperature and pressure regulate the presence and duration of liquid water on the surface of Mars. The prolonged presence of liquid water is essential for the evolution and sustained presence of life on a planet. It has been postulated that Mars has always been a cold dry planet; it has also been postulated that early mars possessed a dense atmosphere of CO2 (> or = 1 bar) and sufficient water to cut large channels across its surface. The degree to which either of these postulates is true correlates with the suitability of Mars for life's evolution. Although radiation can destroy living systems, the high fluxes of UV radiation on the martian surface do not necessarily stop the origin and early evolution of life. The probability for life to have arisen and evolved to a significant degree on Mars, based on the postulated ranges of early martian physical factors, is almost solely related to the probability of liquid water existing on the planet for at least hundreds of millions to billions of years.
Dark energy from the string axiverse.
Kamionkowski, Marc; Pradler, Josef; Walker, Devin G E
2014-12-19
String theories suggest the existence of a plethora of axionlike fields with masses spread over a huge number of decades. Here, we show that these ideas lend themselves to a model of quintessence with no super-Planckian field excursions and in which all dimensionless numbers are order unity. The scenario addresses the "Why now?" problem-i.e., Why has accelerated expansion begun only recently?-by suggesting that the onset of dark-energy domination occurs randomly with a slowly decreasing probability per unit logarithmic interval in cosmic time. The standard axion potential requires us to postulate a rapid decay of most of the axion fields that do not become dark energy. The need for these decays is averted, though, with the introduction of a slightly modified axion potential. In either case, a universe like ours arises in roughly 1 in 100 universes. The scenario may have a host of observable consequences.
Microbial risk assessment in heterogeneous aquifers: 1. Pathogen transport
NASA Astrophysics Data System (ADS)
Molin, S.; Cvetkovic, V.
2010-05-01
Pathogen transport in heterogeneous aquifers is investigated for microbial risk assessment. A point source with time-dependent input of pathogens is assumed, exemplified as a simple on-site sanitation installation, intermingled with water supply wells. Any pathogen transmission pathway (realization) to the receptor from a postulated infection hazard is viewed as a random event, with the hydraulic conductivity varying spatially. For aquifers where VAR[lnK] < 1 and the integral scale is finite, we provide relatively simple semianalytical expressions for pathogen transport that incorporate the colloid filtration theory. We test a wide range of Damkohler numbers in order to assess the significance of rate limitations on the aquifer barrier function. Even slow immobile inactivation may notably affect the retention of pathogens. Analytical estimators for microbial peak discharge are evaluated and are shown to be applicable using parameters representative of rotavirus and Hepatitis A with input of 10-20 days duration.
Analysis of a potential trigger of an acute illness.
Becker, Niels G; Salim, Agus; Kelman, Christopher W
2006-01-01
Sometimes certain short-term risk exposures are postulated to act as a trigger for the onset of a specific acute illness. When the incidence of the illness is low it is desirable to investigate this possible association using only data on cases detected during a specific observation period. Here we propose an analysis for such a study based on a model expressed in terms of the probability that the exposure triggers the illness and a random delay from a triggered illness until its diagnosis. Both the natural hazard rate for the illness and the probability that the exposure triggers the illness are assumed to be small and possibly dependent on age and covariates such as sex and duration or severity of the exposure. The method of analysis is illustrated with a study of the association between long flights and hospitalization for venous thromboembolism.
>From individual choice to group decision-making
NASA Astrophysics Data System (ADS)
Galam, Serge; Zucker, Jean-Daniel
2000-12-01
Some universal features are independent of both the social nature of the individuals making the decision and the nature of the decision itself. On this basis a simple magnet like model is built. Pair interactions are introduced to measure the degree of exchange among individuals while discussing. An external uniform field is included to account for a possible pressure from outside. Individual biases with respect to the issue at stake are also included using local random fields. A unique postulate of minimum conflict is assumed. The model is then solved with emphasis on its psycho-sociological implications. Counter-intuitive results are obtained. At this stage no new physical technicality is involved. Instead the full psycho-sociological implications of the model are drawn. Few cases are then detailed to enlight them. In addition, several numerical experiments based on our model are shown to give both an insight on the dynamics of the model and suggest further research directions.
The Statin–Iron Nexus: Anti-Inflammatory Intervention for Arterial Disease Prevention
DePalma, Ralph G.; Shamayeva, Galina; Chow, Bruce K.
2013-01-01
Objectives. We postulated the existence of a statin–iron nexus by which statins improve cardiovascular disease outcomes at least partially by countering proinflammatory effects of excess iron stores. Methods. Using data from a clinical trial of iron (ferritin) reduction in advanced peripheral arterial disease, the Iron and Atherosclerosis Study, we compared effects of ferritin levels versus high-density lipoprotein to low-density lipoprotein ratios (both were randomization variables) on clinical outcomes in participants receiving and not receiving statins. Results. Statins increased high-density lipoprotein to low-density lipoprotein ratios and reduced ferritin levels by noninteracting mechanisms. Improved clinical outcomes were associated with lower ferritin levels but not with improved lipid status. Conclusions. There are commonalities between the clinical benefits of statins and the maintenance of physiologic iron levels. Iron reduction may be a safe and low-cost alternative to statins. PMID:23409890
Veneziano, D.; Agarwal, A.; Karaca, E.
2009-01-01
The problem of accounting for epistemic uncertainty in risk management decisions is conceptually straightforward, but is riddled with practical difficulties. Simple approximations are often used whereby future variations in epistemic uncertainty are ignored or worst-case scenarios are postulated. These strategies tend to produce sub-optimal decisions. We develop a general framework based on Bayesian decision theory and exemplify it for the case of seismic design of buildings. When temporal fluctuations of the epistemic uncertainties and regulatory safety constraints are included, the optimal level of seismic protection exceeds the normative level at the time of construction. Optimal Bayesian decisions do not depend on the aleatory or epistemic nature of the uncertainties, but only on the total (epistemic plus aleatory) uncertainty and how that total uncertainty varies randomly during the lifetime of the project. ?? 2009 Elsevier Ltd. All rights reserved.
Fly Photoreceptors Encode Phase Congruency
Friederich, Uwe; Billings, Stephen A.; Hardie, Roger C.; Juusola, Mikko; Coca, Daniel
2016-01-01
More than five decades ago it was postulated that sensory neurons detect and selectively enhance behaviourally relevant features of natural signals. Although we now know that sensory neurons are tuned to efficiently encode natural stimuli, until now it was not clear what statistical features of the stimuli they encode and how. Here we reverse-engineer the neural code of Drosophila photoreceptors and show for the first time that photoreceptors exploit nonlinear dynamics to selectively enhance and encode phase-related features of temporal stimuli, such as local phase congruency, which are invariant to changes in illumination and contrast. We demonstrate that to mitigate for the inherent sensitivity to noise of the local phase congruency measure, the nonlinear coding mechanisms of the fly photoreceptors are tuned to suppress random phase signals, which explains why photoreceptor responses to naturalistic stimuli are significantly different from their responses to white noise stimuli. PMID:27336733
Fun Microbiology: Using a Plant Pathogenic Fungus To Demonstrate Koch's Postulates.
ERIC Educational Resources Information Center
Mitchell, James K.; Orsted, Kathy M.; Warnes, Carl E.
1997-01-01
Describes an experiment using a plant pathogenic fungus in which students learn to follow aseptic techniques, grow and produce spores of a fungus, use a hemacytometer for enumerating spores, prepare serial dilutions, grow and inoculate plants, isolate a pure culture using agar streak plates, and demonstrate the four steps of Koch's postulates.…
ERIC Educational Resources Information Center
Bearden, Thomas E.
This document presents a discussion of the postulated mechanism that leads to the materialization and dematerialization of matter and to antigravity. The mechanism also explains why an orbital electron does not radiate energy, in contradiction to classical electromagnetic theory. One of the paradoxes of special relativity is explained. A new model…
Parallels, How Many? Geometry Module for Use in a Mathematics Laboratory Setting.
ERIC Educational Resources Information Center
Brotherton, Sheila; And Others
This is one of a series of geometry modules developed for use by secondary students in a laboratory setting. This module was conceived as an alternative approach to the usual practice of giving Euclid's parallel postulate and then mentioning that alternate postulates would lead to an alternate geometry or geometries. Instead, the student is led…
Preservice and Novice Teachers' Knowledge on Preformal Proofs: Triangle Postulate as an Example
ERIC Educational Resources Information Center
Leung, Kui Chiu Issic; Lee, Chun Yeung
2017-01-01
By considering the example of proving the triangle postulate, this study aimed to explore Hong Kong preservice and novice teachers' knowledge competencies and their beliefs about preformal and formal proofs. The findings revealed that such teachers are not proficient in using preformal proofs and do not realize that preformal proofs are a useful…
ERIC Educational Resources Information Center
Kranzler, John H.; Floyd, Randy G.; Benson, Nicholas; Zaboski, Brian; Thibodaux, Lia
2016-01-01
The Cross-Battery Assessment (XBA) approach to identifying a specific learning disorder (SLD) is based on the postulate that deficits in cognitive abilities in the presence of otherwise average general intelligence are causally related to academic achievement weaknesses. To examine this postulate, we conducted a classification agreement analysis…
Transformational leadership and the mental health team.
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.
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).
[Suicidality and musical preferences: a possible link?].
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].
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.
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.
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.
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).
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.
USDA-ARS?s Scientific Manuscript database
We have fulfilled Koch’s postulates and conducted host range tests with Septoria lepidii Desm. on five geographical accessions of hoary cress. Host range results showed the fungus specific to Lepidium spp. and damaging to hoary cress. This fungus is potentially an important biological control agent ...
Rejoinder in Defense of the Standard Model of the Mind: From Whimsical to Systematic Science
ERIC Educational Resources Information Center
Demetriou, Andreas; Spanoudis, George; Mouyi, Antigoni
2012-01-01
This rejoinder discusses the issues raised by the three commentators of the target article. In agreement with Hunt, it is accepted that, as any overarching theory in any science, it does involve postulates about the mind that must be scrutinized by further research. However, its main postulates are well supported by the findings of specifically…
Dangers of collapsible ventricular drainage systems. Technical note.
Kaye, A H; Wallace, D
1982-02-01
Ventricular drainage systems employing a collapsible plastic bag for fluid collection were postulated to cause an increasing back-pressure produced in part by the elasticity of the bag. This postulate was shown to be correct in an experimental situation. There was a logarithmic rise in cerebrospinal fluid pressure as the bag filled. By increasing the size of the bag, the problem was overcome.
The Foundations of Einstein's Theory of Gravitation
NASA Astrophysics Data System (ADS)
Freundlich, Erwin; Brose, Translated by Henry L.; Einstein, Preface by Albert; Turner, Introduction by H. H.
2011-06-01
Introduction; 1. The special theory of relativity as a stepping-stone to the general theory of relativity; 2. Two fundamental postulates in the mathematical formulation of physical laws; 3. Concerning the fulfilment of the two postulates; 4. The difficulties in the principles of classical mechanics; 5. Einstein's theory of gravitation; 6. The verification of the new theory by actual experience; Appendix; Index.
A numerical test of the topographic bias
NASA Astrophysics Data System (ADS)
Sjöberg, L. E.; Joud, M. S. S.
2018-02-01
In 1962 A. Bjerhammar introduced the method of analytical continuation in physical geodesy, implying that surface gravity anomalies are downward continued into the topographic masses down to an internal sphere (the Bjerhammar sphere). The method also includes analytical upward continuation of the potential to the surface of the Earth to obtain the quasigeoid. One can show that also the common remove-compute-restore technique for geoid determination includes an analytical continuation as long as the complete density distribution of the topography is not known. The analytical continuation implies that the downward continued gravity anomaly and/or potential are/is in error by the so-called topographic bias, which was postulated by a simple formula of L E Sjöberg in 2007. Here we will numerically test the postulated formula by comparing it with the bias obtained by analytical downward continuation of the external potential of a homogeneous ellipsoid to an inner sphere. The result shows that the postulated formula holds: At the equator of the ellipsoid, where the external potential is downward continued 21 km, the computed and postulated topographic biases agree to less than a millimetre (when the potential is scaled to the unit of metre).
Einstein-Cartan calculus for exceptional geometry
NASA Astrophysics Data System (ADS)
Godazgar, Hadi; Godazgar, Mahdi; Nicolai, Hermann
2014-06-01
In this paper we establish and clarify the link between the recently found E7(7) generalised geometric structures, which are based on the SU(8) invariant reformulation of D = 11 supergravity proposed long ago, and newer results obtained in the framework of recent approaches to generalised geometry, where E7(7) duality is built in and manifest from the outset. In making this connection, the so-called generalised vielbein postulate plays a key role. We explicitly show how this postulate can be used to define an E7(7) valued affine connection and an associated covariant derivative, which yields a generalised curvature tensor for the E7(7) based exceptional geometry. The analysis of the generalised vielbein postulate also provides a natural explanation for the emergence of the embedding tensor from higher dimensions.
Cancer stem cells: beyond Koch's postulates.
Garcion, Emmanuel; Naveilhan, Philippe; Berger, François; Wion, Didier
2009-06-08
Until the last century, infectious diseases were the leading cause of human mortality. Therefore, our current medical reasoning is profoundly influenced by views that originated from medical microbiology. The notion that cancer growth is sustained by a sub-population of particular cells, the cancer stem cells, is highly reminiscent of the germ theory of disease as exemplified by Koch's postulates in the XIXth century. However, accumulating data underscore the importance of cell-cell interactions and tumor environment. Hence it is essential to critically review the basic tenets of the cancer stem cell concept on the light of their relationships with Koch's postulates. Shifting the pathogenic element from a special cellular entity (cancer stem cell or microorganism) to a "pathogenic field" could be critical for curing both cancer and drug-resistant infectious diseases.
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.
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.
Prospectively Assessed Posttraumatic Stress Disorder and Associated Physical Activity
2011-05-01
combat, persistent risk, and multiple protracted deployments. Increased psychological symptom reporting has engen - dered heightened concern for the...have pointed to the mental health benefits of physical activity, and researchers have postulated a number of mechanisms by which physical activity may...PTSD. Because researchers have postulated a number of mechanisms by which physical activity may modulate mood and the stress response, it is possible
Masino, Susan A.; Ruskin, David N.
2014-01-01
Ketogenic diets are well-established as a successful anticonvulsant therapy. Based on overlap between mechanisms postulated to underlie pain and inflammation, and mechanisms postulated to underlie therapeutic effects of ketogenic diets, recent studies have explored the ability for ketogenic diets to reduce pain. Here we review clinical and basic research thus far exploring the impact of a ketogenic diet on thermal pain, inflammation, and neuropathic pain. PMID:23680946
Picado, Albert; Das, Murari L; Kumar, Vijay; Kesari, Shreekant; Dinesh, Diwakar S; Roy, Lalita; Rijal, Suman; Das, Pradeep; Rowland, Mark; Sundar, Shyam; Coosemans, Marc; Boelaert, Marleen; Davies, Clive R
2010-01-26
Visceral leishmaniasis (VL) control in the Indian subcontinent is currently based on case detection and treatment, and on vector control using indoor residual spraying (IRS). The use of long-lasting insecticidal nets (LN) has been postulated as an alternative or complement to IRS. Here we tested the impact of comprehensive distribution of LN on the density of Phlebotomus argentipes in VL-endemic villages. A cluster-randomized controlled trial with household P. argentipes density as outcome was designed. Twelve clusters from an ongoing LN clinical trial--three intervention and three control clusters in both India and Nepal--were selected on the basis of accessibility and VL incidence. Ten houses per cluster selected on the basis of high pre-intervention P. argentipes density were monitored monthly for 12 months after distribution of LN using CDC light traps (LT) and mouth aspiration methods. Ten cattle sheds per cluster were also monitored by aspiration. A random effect linear regression model showed that the cluster-wide distribution of LNs significantly reduced the P. argentipes density/house by 24.9% (95% CI 1.80%-42.5%) as measured by means of LTs. The ongoing clinical trial, designed to measure the impact of LNs on VL incidence, will confirm whether LNs should be adopted as a control strategy in the regional VL elimination programs. The entomological evidence described here provides some evidence that LNs could be usefully deployed as part of the VL control program. ClinicalTrials.gov CT-2005-015374.
NASA Astrophysics Data System (ADS)
Nickelsen, Daniel
2017-07-01
The statistics of velocity increments in homogeneous and isotropic turbulence exhibit universal features in the limit of infinite Reynolds numbers. After Kolmogorov’s scaling law from 1941, many turbulence models aim for capturing these universal features, some are known to have an equivalent formulation in terms of Markov processes. We derive the Markov process equivalent to the particularly successful scaling law postulated by She and Leveque. The Markov process is a jump process for velocity increments u(r) in scale r in which the jumps occur randomly but with deterministic width in u. From its master equation we establish a prescription to simulate the She-Leveque process and compare it with Kolmogorov scaling. To put the She-Leveque process into the context of other established turbulence models on the Markov level, we derive a diffusion process for u(r) using two properties of the Navier-Stokes equation. This diffusion process already includes Kolmogorov scaling, extended self-similarity and a class of random cascade models. The fluctuation theorem of this Markov process implies a ‘second law’ that puts a loose bound on the multipliers of the random cascade models. This bound explicitly allows for instances of inverse cascades, which are necessary to satisfy the fluctuation theorem. By adding a jump process to the diffusion process, we go beyond Kolmogorov scaling and formulate the most general scaling law for the class of Markov processes having both diffusion and jump parts. This Markov scaling law includes She-Leveque scaling and a scaling law derived by Yakhot.
Bethel, M A; Harrison, P; Sourij, H; Sun, Y; Tucker, L; Kennedy, I; White, S; Hill, L; Oulhaj, A; Coleman, R L; Holman, R R
2016-02-01
Reduced aspirin efficacy has been demonstrated in people with Type 2 diabetes. Because increased platelet reactivity and/or turnover are postulated mechanisms, we examined whether higher and/or more frequent aspirin dosing might reduce platelet reactivity more effectively. Participants with Type 2 diabetes (n = 24) but without known cardiovascular disease were randomized in a three-way crossover design to 2-week treatment periods with aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily. The primary outcome was platelet reactivity, assessed using the VerifyNow(™) ASA method. Relationships between platelet reactivity and aspirin dosing were examined using generalized linear mixed models with random subject effects. Platelet reactivity decreased from baseline with all doses of aspirin. Modelled platelet reactivity was more effectively reduced with aspirin 100 mg twice daily vs. 100 mg once daily, but not vs. 200 mg once daily. Aspirin 200 mg once daily did not differ from 100 mg once daily. Aspirin 100 mg twice daily was also more effective than once daily as measured by collagen/epinephrine-stimulated platelet aggregation and urinary thromboxane levels, with a similar trend measured by serum thromboxane levels. No episodes of bleeding occurred. In Type 2 diabetes, aspirin 100 mg twice daily reduced platelet reactivity more effectively than 100 mg once daily, and numerically more than 200 mg once daily. Clinical outcome trials evaluating primary cardiovascular disease prevention with aspirin in Type 2 diabetes may need to consider using a more frequent dosing schedule. © 2015 The Authors. Diabetic Medicine © 2015 Diabetes UK.
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.
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.
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
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
DOE Office of Scientific and Technical Information (OSTI.GOV)
Masuda, Y.; Chiba, N.; Matsuo, Y.
This research proposes to investigate the impact behavior of the steel plate of BWR containment vessels against missiles, caused by the postulated catastrophic failure of components with a high kinetic energy. Although the probability of the occurrence of missiles inside and outside of containment vessels is extremely low, the following items are required to maintain the integrity of containment vessels: the probability of the occurrence of missiles, the weight and energy of missiles, and the impact behavior of containment vessel steel plate against postulated missiles. In connection with the third item, an actualscale missile test was conducted. In addition, amore » computation analysis was performed to confirm the impact behavior against the missiles, in order to search for wide applicability to the various kinds of postulated missiles. This research tries to derive a new empirical formula which carries out the assessment of the integrity of containment vessels.« less
Hospitalization patterns associated with Appalachian coal mining.
Hendryx, Michael; Ahern, Melissa M; Nurkiewicz, Timothy R
2007-12-01
The goal of this study was to test whether the volume of coal mining was related to population hospitalization risk for diseases postulated to be sensitive or insensitive to coal mining by-products. The study was a retrospective analysis of 2001 adult hospitalization data (n = 93,952) for West Virginia, Kentucky, and Pennsylvania, merged with county-level coal production figures. Hospitalization data were obtained from the Health Care Utilization Project National Inpatient Sample. Diagnoses postulated to be sensitive to coal mining by-product exposure were contrasted with diagnoses postulated to be insensitive to exposure. Data were analyzed using hierarchical nonlinear models, controlling for patient age, gender, insurance, comorbidities, hospital teaching status, county poverty, and county social capital. Controlling for covariates, the volume of coal mining was significantly related to hospitalization risk for two conditions postulated to be sensitive to exposure: hypertension and chronic obstructive pulmonary disease (COPD). The odds for a COPD hospitalization increased 1% for each 1462 tons of coal, and the odds for a hypertension hospitalization increased 1% for each 1873 tons of coal. Other conditions were not related to mining volume. Exposure to particulates or other pollutants generated by coal mining activities may be linked to increased risk of COPD and hypertension hospitalizations. Limitations in the data likely result in an underestimate of associations.
Structural models of the MscL gating mechanism
NASA Technical Reports Server (NTRS)
Sukharev, S.; Durell, S. R.; Guy, H. R.
2001-01-01
Three-dimensional structural models of the mechanosensitive channel of large conductance, MscL, from the bacteria Mycobacterium tuberculosis and Escherichia coli were developed for closed, intermediate, and open conformations. The modeling began with the crystal structure of M. tuberculosis MscL, a homopentamer with two transmembrane alpha-helices, M1 and M2, per subunit. The first 12 N-terminal residues, not resolved in the crystal structure, were modeled as an amphipathic alpha-helix, called S1. A bundle of five parallel S1 helices are postulated to form a cytoplasmic gate. As membrane tension induces expansion, the tilts of M1 and M2 are postulated to increase as they move away from the axis of the pore. Substantial expansion is postulated to occur before the increased stress in the S1 to M1 linkers pulls the S1 bundle apart. During the opening transition, the S1 helices and C-terminus amphipathic alpha-helices, S3, are postulated to dock parallel to the membrane surface on the perimeter of the complex. The proposed gating mechanism reveals critical spatial relationships between the expandable transmembrane barrel formed by M1 and M2, the gate formed by S1 helices, and "strings" that link S1s to M1s. These models are consistent with numerous experimental results and modeling criteria.
[Dentinal hypersensitivity in periodontal disease. Aetiology Aetiology--management].
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].
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.
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.
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.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bearden, T.E.
1975-10-08
This report presents a discussion of the postulated mechanism that leads to the materialization and dematerialization of matter and to antigravity. The mechanism also explains why an orbital electron does not radiate energy, in contradiction to classical electromagnetic theory. One of the paradoxes of special relativity is explained. A new model of a photon is advanced. The relativistic increase of mass with velocity is explained. (GRA)
2017-01-01
associated with continued problematic use and relapse is craving. Three different types of craving have been hypothesized, reward , relief, and obsessive...and each is postulated to be mediated by different neurological substrates. The neural networks postulated to subserve reward and relief craving...noradrenergic system with craving-related brain systems , blocking α1 receptors with the noradrenergic antagonist, prazosin, theoretically has the
Mechanism-based inactivation of dopamine beta-hydroxylase by p-cresol and related alkylphenols
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goodhart, P.J.; DeWolf, W.E. Jr.; Kruse, L.I.
1987-05-05
The mechanism-based inhibition of dopamine beta-hydroxylase by p-cresol (4-methylphenol) and other simple structural analogues of dopamine, which lack a basic side-chain nitrogen, is reported. p-Cresol binds DBH by a mechanism that is kinetically indistinguishable from normal dopamine substrate binding. Under conditions (pH 6.6) of random oxygen and phenethylamine substrate addition p-cresol adds randomly, whereas at pH 4.5 or in the presence of fumarate activator addition of p-cresol precedes oxygen binding as is observed with phenethylamine substrate. p-Cresol is shown to be a rapid (kinact = 2.0 min-1, pH 5.0) mechanism-based inactivator of DBH. This inactivation exhibits pseudo-first-order kinetics, is irreversible,more » is prevented by tyramine substrate or competitive inhibitor, and is dependent upon oxygen and ascorbic acid cosubstrates. Inhibition occurs with partial covalent incorporation of p-cresol into DBH. A plot of -log kinact vs. pH shows maximal inactivation occurs at pH 5.0 with dependence upon enzymatic groups with apparent pK values of 4.51 +/- 0.06 and 5.12 +/- 0.06. p-Cresol and related alkylphenols, unlike other mechanism-based inhibitors of DBH, lack a latent electrophile. These inhibitors are postulated to covalently modify DBH by a direct insertion of an aberrant substrate-derived benzylic radical into an active site residue.« less
A minimalist approach to conceptualization of time in quantum theory
NASA Astrophysics Data System (ADS)
Kitada, Hitoshi; Jeknić-Dugić, Jasmina; Arsenijević, Momir; Dugić, Miroljub
2016-12-01
Ever since Schrödinger, Time in quantum theory is postulated Newtonian for every reference frame. With the help of certain known mathematical results, we show that the concept of the so-called Local Time allows avoiding the postulate. In effect, time appears as neither fundamental nor universal on the quantum-mechanical level while being consistently attributable to every, at least approximately, closed quantum system as well as to every of its (conservative or not) subsystems.
Quantum mechanics without the projection postulate and its realistic interpretation
NASA Astrophysics Data System (ADS)
Dieks, D.
1989-11-01
It is widely held that quantum mechanics is the first scientific theory to present scientifically internal, fundamental difficulties for a realistic interpretation (in the philosophical sense). The standard (Copenhagen) interpretation of the quantum theory is often described as the inevitable instrumentalistic response. It is the purpose of the present article to argue that quantum theory does not present fundamental new problems to a realistic interpretation. The formalism of quantum theory has the same states—it will be argued—as the formalisms of older physical theories and is capable of the same kinds of philosophical interpretation. This result is reached via an analysis of what it means to give a realistic interpretation to a theory. The main point of difference between quantum mechanics and other theories—as far as the possibilities of interpretation are concerned—is the special treatment given to measurement by the “projection postulate.” But it is possible to do without this postulate. Moreover, rejection of the projection postulate does not, in spite of what is often maintained in the literature, automatically lead to the many-worlds interpretation of quantum mechanics. A realistic interpretation is possible in which only the reality of one (our) world is recognized. It is argued that the Copenhagen interpretation as expounded by Bohr is not in conflict with the here proposed realistic interpretation of quantum theory.
Chau, Kenneth J; Lezec, Henri J
2012-04-23
We propose a set of postulates to describe the mechanical interaction between a plane-wave electromagnetic pulse and a dispersive, dissipative slab having a refractive index of arbitrary sign. The postulates include the Abraham electromagnetic momentum density, a generalized Lorentz force law, and a model for absorption-driven mass transfer from the pulse to the medium. These opto-mechanical mechanisms are incorporated into a one-dimensional finite-difference time-domain algorithm that solves Maxwell's equations and calculates the instantaneous force densities exerted by the pulse onto the slab, the momentum-per-unit-area of the pulse and slab, and the trajectories of the slab and system center-of-mass. We show that the postulates are consistent with conservation of global energy, momentum, and center-of-mass velocity at all times, even for cases in which the refractive index of the slab is negative or zero. Consistency between the set of postulates and well-established conservation laws reinforces the Abraham momentum density as the one true electromagnetic momentum density and enables, for the first time, identification of the correct form of the electromagnetic mass density distribution and development of an explicit model for mass transfer due to absorption, for the most general case of a ponderable medium that is both dispersive and dissipative. © 2012 Optical Society of America
Spatial heterogeneity of climate change as an experiential basis for skepticism
Kaufmann, Robert K.; Mann, Michael L.; Gopal, Sucharita; Liederman, Jackie A.; Howe, Peter D.; Pretis, Felix; Gilmore, Michelle
2017-01-01
We postulate that skepticism about climate change is partially caused by the spatial heterogeneity of climate change, which exposes experiential learners to climate heuristics that differ from the global average. This hypothesis is tested by formalizing an index that measures local changes in climate using station data and comparing this index with survey-based model estimates of county-level opinion about whether global warming is happening. Results indicate that more stations exhibit cooling and warming than predicted by random chance and that spatial variations in these changes can account for spatial variations in the percentage of the population that believes that “global warming is happening.” This effect is diminished in areas that have experienced more record low temperatures than record highs since 2005. Together, these results suggest that skepticism about climate change is driven partially by personal experiences; an accurate heuristic for local changes in climate identifies obstacles to communicating ongoing changes in climate to the public and how these communications might be improved. PMID:27994143
Representation of dental care and oral health in children's drawings.
Torriani, D D; Goettems, M L; Cademartori, M G; Fernandez, R R; Bussoletti, D M
2014-06-01
Paediatric dentistry requires knowledge of preventive measures, restorative skills and an understanding of child development. This exploratory, descriptive and qualitative study has analysed children's drawings regarding their perception of dental treatment and oral health. Children aged from six to ten years attending a dental school for treatment were randomly invited to create a drawing about 'dental treatment' and 'oral health'. Verbal expressions made by the children whilst drawing were also recorded and attached to the drawings. These representations were analysed and categorised using Vygotsky postulations for context reading. During the drawing analysis different themes emerged. Five categories regarding perceptions of dental treatment were identified: personal relationship; power relation; trauma; childhood resistance; and contextualisation of dental care in the child's life. Three categories relating to oral health were determined: dichotomy of health/sickness; ludic representation of health; and sickness seen as a process. Drawing can be used to understand children's emotions and expectations about dental treatment. Besides possessing technical skills and scientific knowledge, dentists have an obligation to pay attention to children's feelings.
Spatial heterogeneity of climate change as an experiential basis for skepticism.
Kaufmann, Robert K; Mann, Michael L; Gopal, Sucharita; Liederman, Jackie A; Howe, Peter D; Pretis, Felix; Tang, Xiaojing; Gilmore, Michelle
2017-01-03
We postulate that skepticism about climate change is partially caused by the spatial heterogeneity of climate change, which exposes experiential learners to climate heuristics that differ from the global average. This hypothesis is tested by formalizing an index that measures local changes in climate using station data and comparing this index with survey-based model estimates of county-level opinion about whether global warming is happening. Results indicate that more stations exhibit cooling and warming than predicted by random chance and that spatial variations in these changes can account for spatial variations in the percentage of the population that believes that "global warming is happening." This effect is diminished in areas that have experienced more record low temperatures than record highs since 2005. Together, these results suggest that skepticism about climate change is driven partially by personal experiences; an accurate heuristic for local changes in climate identifies obstacles to communicating ongoing changes in climate to the public and how these communications might be improved.
Empirical microeconomics action functionals
NASA Astrophysics Data System (ADS)
Baaquie, Belal E.; Du, Xin; Tanputraman, Winson
2015-06-01
A statistical generalization of microeconomics has been made in Baaquie (2013), where the market price of every traded commodity, at each instant of time, is considered to be an independent random variable. The dynamics of commodity market prices is modeled by an action functional-and the focus of this paper is to empirically determine the action functionals for different commodities. The correlation functions of the model are defined using a Feynman path integral. The model is calibrated using the unequal time correlation of the market commodity prices as well as their cubic and quartic moments using a perturbation expansion. The consistency of the perturbation expansion is verified by a numerical evaluation of the path integral. Nine commodities drawn from the energy, metal and grain sectors are studied and their market behavior is described by the model to an accuracy of over 90% using only six parameters. The paper empirically establishes the existence of the action functional for commodity prices that was postulated to exist in Baaquie (2013).
Recommendations for Management of Patients with Carotid Stenosis
Lovrencic-Huzjan, Arijana; Rundek, Tatjana; Katsnelson, Michael
2012-01-01
Stroke is a one of the leading causes of morbidity and mortality in the world. Carotid atherosclerosis is recognized as an important factor in stroke pathophysiology and represents a key target in stroke prevention; multiple treatment modalities have been developed to battle this disease. Multiple randomized trials have shown the efficacy of carotid endarterectomy in secondary stroke prevention. Carotid stenting, a newer treatment option, presents a less invasive alternative to the surgical intervention on carotid arteries. Advances in medical therapy have also enabled further risk reduction in the overall incidence of stroke. Despite numerous trials and decades of clinical research, the optimal management of symptomatic and asymptomatic carotid disease remains controversial. We will attempt to highlight some of the pivotal trials already completed, discuss the current controversies and complexities in the treatment decision-making, and postulate on what likely lies ahead. This paper will highlight the complexities of decision-making optimal treatment recommendations for patients with symptomatic and asymptomatic carotid stenosis. PMID:22645702
Schoberer, Daniela; Breimaier, Helga E; Mandl, Manuela; Halfens, Ruud J G; Lohrmann, Christa
2016-01-01
This study aims to explore and compare nursing home residents', family members', and nursing staff's needs and expectations regarding a fall prevention brochure. Focus groups were carried out with 25 residents, 12 family members and 14 nursing staff separately, from three randomly selected nursing homes. Qualitative content analysis was used to analyze the data using a concept-driven coding frame. Results showed that residents want to be informed about dealing with extrinsic fall risks and coping strategies after a fall event. In addition, family members wanted to have detailed information on intrinsic fall risks as well as specific fall prevention strategies, such as body exercises. Of special importance for nursing staff was that not all falls are preventable even when preventive measures were taken. As the need and expectations of users differ substantially, one brochure could not comprise all postulated criteria and different brochures are necessary for residents and for family members. Copyright © 2016 Elsevier Inc. All rights reserved.
Han, Gajin; Park, Jae-Woo; Ko, Seok-Jae; Son, Jihee; Seon, Jongki; Kim, Juyeon; Kim, Seulki; Yeo, Inkwon; Ryu, Bongha; Kim, Jinsung
2013-09-03
Xerostomia, a subjective sense of dry mouth, is not generally regarded a disease despite its high prevalence among the elderly, and therefore continues to impair affected patients' quality of life. In traditional Korean medicine, 'Yin-Deficiency' has been implicated in the pathogenesis of xerostomia among the elderly. Yukmijihwang-tang is a famous herbal prescription used to relieve 'Yin-Deficiency', and reportedly has antioxidant effects; therefore, it is postulated that Yukmijihwang-tang can be used to treat xerostomia in the elderly. However, to our knowledge, no clinical trial has been conducted on the effects of Yukmijihwang-tang on xerostomia. Thus, we designed a randomized clinical trial to investigate the effects and safety of Yukmijihwang-tang on xerostomia in the elderly. In addition, we will clarify the aforementioned assumption that 'Yin-Deficiency' is the major cause of xerostomia in the elderly by identifying a correlation between xerostomia and 'Yin-Deficiency'. This randomized, double-blind, placebo-controlled trial will be carried out at two centers: Kyung Hee University Korean Medicine Hospital and Kyung Hee University Hospital at Gangdong. We will recruit 96 subjects aged 60-80 years who have experienced xerostomia for 3 months prior to participation. Subjects who present with score >40 on the visual analogue scale for xerostomia and unstimulated salivary flow rate under 0.3mL/min will be included and the randomization will be carried out by an independent statistician by using a random number creation program. The subjects and all researchers except the statistician will be blinded to the group assignment. Yukmijihwang-tang or placebo will be administered to each group for 8 weeks. The primary outcome is change in the scores for the visual analogue scale for xerostomia and the dry mouth symptom questionnaire from 0 to 8 weeks. It will be assessed whether Yukmijihwang-tang can be used as a new herbal treatment for xerostomia in the elderly by demonstrating its therapeutic effects in a well-designed clinical trial. ClinicalTrials.gov Identifier: NCT01579877.
2013-01-01
Background Xerostomia, a subjective sense of dry mouth, is not generally regarded a disease despite its high prevalence among the elderly, and therefore continues to impair affected patients’ quality of life. In traditional Korean medicine, ‘Yin-Deficiency’ has been implicated in the pathogenesis of xerostomia among the elderly. Yukmijihwang-tang is a famous herbal prescription used to relieve ‘Yin-Deficiency’, and reportedly has antioxidant effects; therefore, it is postulated that Yukmijihwang-tang can be used to treat xerostomia in the elderly. However, to our knowledge, no clinical trial has been conducted on the effects of Yukmijihwang-tang on xerostomia. Thus, we designed a randomized clinical trial to investigate the effects and safety of Yukmijihwang-tang on xerostomia in the elderly. In addition, we will clarify the aforementioned assumption that ‘Yin-Deficiency’ is the major cause of xerostomia in the elderly by identifying a correlation between xerostomia and ‘Yin-Deficiency’. Methods/Design This randomized, double-blind, placebo-controlled trial will be carried out at two centers: Kyung Hee University Korean Medicine Hospital and Kyung Hee University Hospital at Gangdong. We will recruit 96 subjects aged 60-80 years who have experienced xerostomia for 3 months prior to participation. Subjects who present with score >40 on the visual analogue scale for xerostomia and unstimulated salivary flow rate under 0.3mL/min will be included and the randomization will be carried out by an independent statistician by using a random number creation program. The subjects and all researchers except the statistician will be blinded to the group assignment. Yukmijihwang-tang or placebo will be administered to each group for 8 weeks. The primary outcome is change in the scores for the visual analogue scale for xerostomia and the dry mouth symptom questionnaire from 0 to 8 weeks. Discussion It will be assessed whether Yukmijihwang-tang can be used as a new herbal treatment for xerostomia in the elderly by demonstrating its therapeutic effects in a well-designed clinical trial. Trial registration ClinicalTrials.gov Identifier: NCT01579877 PMID:24004451
Johnson, Kara; McEvoy, Charlene E; Naqvi, Sakina; Wendt, Chris; Reilkoff, Ronald A; Kunisaki, Ken M; Wetherbee, Erin E; Nelson, David; Tirouvanziam, Rabindra; Niewoehner, Dennis E
2016-01-01
Clinical outcomes are worse in patients with COPD and chronic bronchitis. N-acetylcysteine (NAC) is commonly prescribed for such patients but with uncertain clinical benefits. We postulated that oral NAC, at much larger doses than those ordinarily prescribed, would improve clinical outcomes in a subset of patients with COPD and chronic bronchitis. The aim of this study was to determine whether very high-dose NAC would improve respiratory health status in patients with COPD and chronic bronchitis. Patients with COPD and chronic bronchitis were enrolled in a randomized, controlled, double-blinded trial. Patients received oral NAC (1,800 mg) or matching placebo twice daily for 8 weeks in addition to their usual respiratory medications. The primary outcome, respiratory health status, was assessed by changes in the St George's Respiratory Questionnaire. The effects of NAC on lung function and circulating markers of oxidative stress and inflammation were also evaluated. We terminated the study prematurely because new external information suggested the possibility of a safety issue. Of the planned 130 patients, 51 were randomized and 45 (22 in the placebo arm and 23 in the NAC arm) completed the study. There was no statistically significant difference between changes in the St George's Respiratory Questionnaire total score, comparing NAC to placebo (adjusted mean difference, 0.1 U; 95% CI, -7.8 to 8.18 U; P=0.97). There were also no significant NAC-related improvements in any of the secondary outcomes. In this 8-week trial, we were unable to show any clinical benefit from a very high dose of NAC in patients with COPD and chronic bronchitis.
Effect of coenzyme Q10 supplementation on heart failure: a meta-analysis123
Thompson-Paul, Angela M; Bazzano, Lydia A
2013-01-01
Background: Coenzyme Q10 (CoQ10; also called ubiquinone) is an antioxidant that has been postulated to improve functional status in congestive heart failure (CHF). Several randomized controlled trials have examined the effects of CoQ10 on CHF with inconclusive results. Objective: The objective of this meta-analysis was to evaluate the impact of CoQ10 supplementation on the ejection fraction (EF) and New York Heart Association (NYHA) functional classification in patients with CHF. Design: A systematic review of the literature was conducted by using databases including MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and manual examination of references from selected studies. Studies included were randomized controlled trials of CoQ10 supplementation that reported the EF or NYHA functional class as a primary outcome. Information on participant characteristics, trial design and duration, treatment, dose, control, EF, and NYHA classification were extracted by using a standardized protocol. Results: Supplementation with CoQ10 resulted in a pooled mean net change of 3.67% (95% CI: 1.60%, 5.74%) in the EF and −0.30 (95% CI: −0.66, 0.06) in the NYHA functional class. Subgroup analyses showed significant improvement in EF for crossover trials, trials with treatment duration ≤12 wk in length, studies published before 1994, and studies with a dose ≤100 mg CoQ10/d and in patients with less severe CHF. These subgroup analyses should be interpreted cautiously because of the small number of studies and patients included in each subgroup. Conclusions: Pooled analyses of available randomized controlled trials suggest that CoQ10 may improve the EF in patients with CHF. Additional well-designed studies that include more diverse populations are needed. PMID:23221577
Niemier, K; Schindler, M; Volk, T; Baum, K; Wolf, B; Eberitsch, J; Seidel, W
2015-07-01
Chronic lumbar pain syndromes without neurological deficits are generated by a multitude of causes. Functional, morphological and psychosocial factors are discussed. In many cases a diseased intervertebral disc is found on radiological examination but the clinical relevance of these findings is not clear. For this study it was postulated that a diseased disc results in a local inflammatory reaction therefore causing pain and impairing treatability of patients. An epidural injection of steroids can reduce inflammation and therefore improve treatability and ultimately treatment outcome. A double blind randomized prospective trial was carried out. Patients treated in hospital for a chronic lumbar pain syndrome without neurological deficits within a multimodal treatment program were screened for indications for an epidural steroid injection (e.g. diseased lumbar disc and intention to treat). Patients eligible for the study were randomized into two groups. The treatment group received an epidural injection of 80 mg triamcinolone and 8 ml bupivacaine 0.25 %. The control group received only an epidural injection of 8 ml bupivacaine 0.25 %. In both groups pain intensity and treatability showed a statistically significant improvement after the epidural injection. The differences between the control and treatment groups were small and not clinically relevant. A small subgroup might profit from the steroid injection. In addition the treatability was dependent on psychometric values and the long-term outcome from a reduction of muscular skeletal dysfunctions. After the epidural injection the decrease in pain and increase in treatability was statistically significant. The mechanism of the improvement is not clear and should be examined further. The epidural injection of a steroid in this subgroup of patients did not lead to a clinical improvement in the outcome.
Molecules for security measures: from keypad locks to advanced communication protocols.
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.
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.
[Risk/protective factors and prevention programs for drug dependence in Peru].
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.
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 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.
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.
On peaceful coexistence: is the collapse postulate incompatible with relativity?
NASA Astrophysics Data System (ADS)
Myrvold, Wayne C.
In this paper, it is argued that the prima facie conflict between special relativity and the quantum-mechanical collapse postulate is only apparent, and that the seemingly incompatible accounts of entangled systems undergoing collapse yielded by different reference frames can be regarded as no more than differing accounts of the same processes and events. Attention to the transformation properties of quantum-mechanical states undergoing unitary, non-collapse evolution points the way to a treatment of collapse evolution consistent with the demands of relativity.
The Four Postulates of Freudian Unconscious Neurocognitive Convergences
Arminjon, Mathieu
2011-01-01
In the 1980s, the terms “cognitive unconscious” were invented to denominate a perspective on unconscious mental processes independent from the psychoanalytical views. For several reasons, the two approaches to unconscious are generally conceived as irreducible. Nowadays, we are witnessing a certain convergence between both fields. The aim of this paper consists in examining the four basic postulates of Freudian unconscious at the light of neurocognitive sciences. They posit: (1) that some psychological processes are unconsciously performed and causally determine conscious processes, (2) that they are governed by their own cognitive rules, (3) that they set out their own intentions, (4) and that they lead to a conflicting organization of psyche. We show that each of these postulates is the subject of empirical and theoretical works. If the two fields refer to more or less similar mechanisms, we propose that their opposition rests on an epistemological misunderstanding. As a conclusion, we promote a conservative reunification of the two perspectives. PMID:21734896
Selection of Differential Isolates of Magnaporthe oryzae for Postulation of Blast Resistance Genes.
Fang, W W; Liu, C C; Zhang, H W; Xu, H; Zhou, S; Fang, K X; Peng, Y L; Zhao, W S
2018-05-21
A set of differential isolates of Magnaporthe oryzae is needed for the postulation of blast resistance genes in numerous rice varieties and breeding materials. In this study, the pathotypes of 1,377 M. oryzae isolates from different regions of China were determined by inoculating detached rice leaves of 24 monogenic lines. Among them, 25 isolates were selected as differential isolates based on the following characteristics: they had distinct responses on the monogenic lines, contained the minimum number of avirulence genes, were stable in pathogenicity and conidiation during consecutive culture, were consistent colony growth rate, and, together, could differentiate combinations of the 24 major blast resistance genes. Seedlings of rice cultivars were inoculated with this differential set of isolates to postulate whether they contain 1 or more than 1 of the 24 blast resistance genes. The results were consistent with those from polymerase chain reaction analysis of target resistance genes. Establishment of a standard set of differential isolates will facilitate breeding for blast resistance and improved management of rice blast disease.
Nonlinear damage analysis: Postulate and evaluation
NASA Technical Reports Server (NTRS)
Leis, B. N.; Forte, T. P.
1983-01-01
The objective of this program is to assess the viability of a damage postulate which asserts that the fatigue resistance curve of a metal is history dependent due to inelastic action. The study focusses on OFE copper because this simple model material accentuates the inelastic action central to the damage postulate. Data relevant to damage evolution and crack initiation are developed via a study of surface topography. The effects of surface layer residual stresses are explored via comparative testing as were the effects in initial prestraining. The results of the study very clearly show the deformation history dependence of the fatigue resistance of OFE copper. Furthermore the concept of deformation history dependence is shown to qualitatively explain the fatigue resistance of all histories considered. Likewise quantitative predictions for block cycle histories are found to accurately track the observed results. In this respect the assertion that damage per cycle for a given level of the damage parameter is deformation history dependent appears to be physically justified.
Why does serotonergic activity drastically decrease during REM sleep?
Sato, Kohji
2013-10-01
Here, I postulate two hypotheses that can explain the missing link between sleep and the serotonergic system in terms of spine homeostasis and memory consolidation. As dendritic spines contain many kinds of serotonin receptors, and the activation of serotonin receptors generally increases the number of spines in the cortex and hippocampus, I postulate that serotonin neurons are down-regulated during sleep to decrease spine number, which consequently maintains the total spine number at a constant level. Furthermore, since synaptic consolidation during REM sleep needs long-term potentiation (LTP), and serotonin is reported to inhibit LTP in the cortex, I postulate that serotonergic activity must drastically decrease during REM sleep to induce LTP and do memory consolidation. Until now, why serotonergic neurons show these dramatic changes in the sleep-wake cycle remains unexplained; however, making these hypotheses, I can confer physiological meanings on these dramatic changes of serotonergic neurons in terms of spine homeostasis and memory consolidation. Copyright © 2013. Published by Elsevier Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kozluk, M.J.; Vijay, D.K.
Postulated catastrophic rupture of high-energy piping systems is the fundamental criterion used for the safety design basis of both light and heavy water nuclear generating stations. Historically, the criterion has been applied by assuming a nonmechanistic instantaneous double-ended guillotine rupture of the largest diameter pipes inside of containment. Nonmechanistic, meaning that the assumption of an instantaneous guillotine rupture has not been based on stresses in the pipe, failure mechanisms, toughness of the piping material, nor the dynamics of the ruptured pipe ends as they separate. This postulated instantaneous double-ended guillotine rupture of a pipe was a convenient simplifying assumption thatmore » resulted in a conservative accident scenario. This conservative accident scenario has now become entrenched as the design basis accident for: containment design, shutdown system design, emergency fuel cooling systems design, and to establish environmental qualification temperature and pressure conditions. The requirement to address dynamic effects associated with the postulated pipe rupture subsequently evolved. The dynamic effects include: potential missiles, pipe whipping, blowdown jets, and thermal-hydraulic transients. Recent advances in fracture mechanics research have demonstrated that certain pipes under specific conditions cannot crack in ways that result in an instantaneous guillotine rupture. Canadian utilities are now using mechanistic fracture mechanics and leak-before-break assessments on a case-by-case basis, in limited applications, to support licensing cases which seek exemption from the need to consider the various dynamic effects associated with postulated instantaneous catastrophic rupture of high-energy piping systems inside and outside of containment.« less
Whiplash injuries of the temporomandibular joint in motor vehicle accidents: speculations and facts.
McKay, D C; Christensen, L V
1998-10-01
Referring to the temporomandibular joint (TMJ) of the human mandibular locomotor system, it has been asserted that displacement of the TMJ disc and inflammation of TMJ tissues are the results of acute and indirect trauma to the TMJ; on occasion this is allegedly experienced in motor vehicle accidents and commonly known as a TMJ whiplash injury. It is postulated that the TMJ whiplash injury is released in the occupant or occupants of a target vehicle when its rear end is impacted by the front end of a bullet vehicle. On the basis of detailed analyses of TMJ trauma/pain histories and TMJ magnetic resonance images, presented as circumstantial evidence in favour of the postulated TMJ whiplash injury, and detailed analyses of the mathematical biophysics of the mandibular locomotor system as well as direct experimental evidence, it is concluded that the postulated TMJ whiplash injury does not exist as a single and independent disease entity caused by motor vehicle accidents. If TMJ disc displacement and inflammation are present, they are expressions of an insidious and progressive pre-existing (pre-accident) disease entity that is comprised of TMJ synovitis/osteoarthritis (phase of inflammation with presence of immune system cells), TMJ internal derangement (phase of disc displacement and deformation with presence of proteinases), and TMJ osteoarthrosis (phase of degeneration with absence of immune system cells). For the asserted TMJ whiplash manoeuvre and ensuing injury to occur as postulated, the laws of physics and biology would have to be suspended.
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
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.
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.
NASA Astrophysics Data System (ADS)
Assis, A. K. T.
1989-08-01
We propose the postulate that the resultant force acting on any body is zero. With this postulate and with a Weber force law for gravitation, we obtain equations of motion and conclude that all inertial forces are due to gravitational interaction with other bodies in the universe, as suggested by Mach. We then obtain the same value for the advance of the perhelion of the planets as is given by general relativity. All this is accomplished in a strictly relational theory. Finally, we relate these points to topical questions of electrodynamics raised by the experimental studies of Graneau and Pappas.
Toward a genealogy of culture.
Rendon, M
2001-12-01
Using psychoanalytic theory, this paper attempts to trace the natural history of the phenomenon designated as Culture. It postulates that psychoanalysis, a product of the Hegelian philosophical revolution, is still one of the best instruments to understand Culture. It traces the origins of culture as postulated by Freud and the pioneer anthropologists and its course from early and evolved religion through humanism, science, and finally postmodernism. It emphasizes the dialectical concepts in psychoanalysis and reviews summarily those psychoanalysts that, according to the author, have had a major impact on the study of culture: Freud, Horney, and Lacan.
2014-10-01
to cause other cancer susceptibility (CDKN2A, MLH1, MSH2, MSH6, PMS2 ); 3) genes known or postulated to be moderate penetrance cancer susceptibility...susceptibility (CDKN2A, MLH1, MSH2, MSH6, PMS2 ); 3) genes known or postulated to be moderate penetrance cancer susceptibility genes (ATM, BARD1, BRIP1...AK, Lindor NM, Jenkins MA. Risk of breast cancer in Lynch syndrome : a systematic review. Breast Cancer Res 2013;15:R27. 55. Brunet J, Gutierrez
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].
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.
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.
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].
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.
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.
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.
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.
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.
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
Newton, Katherine M; Carpenter, Janet S; Guthrie, Katherine A; Anderson, Garnet L; Caan, Bette; Cohen, Lee S; Ensrud, Kristine E; Freeman, Ellen W; Joffe, Hadine; Sternfeld, Barbara; Reed, Susan D; Sherman, Sheryl; Sammel, Mary D; Kroenke, Kurt; Larson, Joseph C; Lacroix, Andrea Z
2014-01-01
This report describes the Menopausal Strategies: Finding Lasting Answers to Symptoms and Health network and methodological issues addressed in designing and implementing vasomotor symptom trials. Established in response to a National Institutes of Health request for applications, the network was charged with conducting rapid throughput randomized trials of novel and understudied available interventions postulated to alleviate vasomotor and other menopausal symptoms. Included are descriptions of and rationale for criteria used for interventions and study selection, common eligibility and exclusion criteria, common primary and secondary outcome measures, consideration of placebo response, establishment of a biorepository, trial duration, screening and recruitment, statistical methods, and quality control. All trial designs are presented, including the following: (1) a randomized, double-blind, placebo-controlled clinical trial designed to evaluate the effectiveness of the selective serotonin reuptake inhibitor escitalopram in reducing vasomotor symptom frequency and severity; (2) a two-by-three factorial design trial to test three different interventions (yoga, exercise, and ω-3 supplementation) for the improvement of vasomotor symptom frequency and bother; and (3) a three-arm comparative efficacy trial of the serotonin-norepinephrine reuptake inhibitor venlafaxine and low-dose oral estradiol versus placebo for reducing vasomotor symptom frequency. The network's structure and governance are also discussed. The methods used in and the lessons learned from the Menopausal Strategies: Finding Lasting Answers to Symptoms and Health trials are shared to encourage and support the conduct of similar trials and to encourage collaborations with other researchers.
Transference interpretations in dynamic psychotherapy: do they really yield sustained effects?
Høglend, Per; Bøgwald, Kjell-Petter; Amlo, Svein; Marble, Alice; Ulberg, Randi; Sjaastad, Mary Cosgrove; Sørbye, Oystein; Heyerdahl, Oscar; Johansson, Paul
2008-06-01
Transference interpretation has remained a core ingredient in the psychodynamic tradition, despite limited empirical evidence for its effectiveness. In this study, the authors examined long-term effects of transference interpretations. This was a randomized controlled clinical trial, dismantling design, plus follow-up evaluations 1 year and 3 years after treatment termination. One hundred outpatients seeking psychotherapy for depression, anxiety, personality disorders, and interpersonal problems were referred to the study therapists. Patients were randomly assigned to receive weekly sessions of dynamic psychotherapy for 1 year with or without transference interpretations. Five full sessions from each therapy were rated in order to document treatment fidelity. Outcome variables were the Psychodynamic Functioning Scales (clinician rated) and the Inventory of Interpersonal Problems (self-report). Rating on the Quality of Object Relations Scale (lifelong pattern) and presence of a personality disorder were postulated moderators of treatment effects. Change over time was assessed using linear mixed models. Despite an absence of differential treatment efficacy, both treatments demonstrated significant improvement during treatment and also after treatment termination. However, patients with a lifelong pattern of poor object relations profited more from 1 year of therapy with transference interpretations than from therapy without transference interpretations. This effect was sustained throughout the 4-year study period. The goal of transference interpretation is sustained improvement of the patient's relationships outside of therapy. Transference interpretation seems to be especially important for patients with long-standing, more severe interpersonal problems.
Catalytic Activities Of [GADV]-Peptides
NASA Astrophysics Data System (ADS)
Oba, Takae; Fukushima, Jun; Maruyama, Masako; Iwamoto, Ryoko; Ikehara, Kenji
2005-10-01
We have previously postulated a novel hypothesis for the origin of life, assuming that life on the earth originated from “[GADV]-protein world”, not from the “RNA world” (see Ikehara's review, 2002). The [GADV]-protein world is constituted from peptides and proteins with random sequences of four amino acids (glycine [G], alanine [A], aspartic acid [D] and valine [V]), which accumulated by pseudo-replication of the [GADV]-proteins. To obtain evidence for the hypothesis, we produced [GADV]-peptides by repeated heat-drying of the amino acids for 30 cycles ([GADV]-P30) and examined whether the peptides have some catalytic activities or not. From the results, it was found that the [GADV]-P30 can hydrolyze several kinds of chemical bonds in molecules, such as umbelliferyl-β-D-galactoside, glycine-p-nitroanilide and bovine serum albumin. This suggests that [GADV]-P30 could play an important role in the accumulation of [GADV]-proteins through pseudo-replication, leading to the emergence of life. We further show that [GADV]-octapaptides with random sequences, but containing no cyclic compounds as diketepiperazines, have catalytic activity, hydrolyzing peptide bonds in a natural protein, bovine serum albumin. The catalytic activity of the octapeptides was much higher than the [GADV]-P30 produced through repeated heat-drying treatments. These results also support the [GADV]-protein-world hypothesis of the origin of life (see Ikehara's review, 2002). Possible steps for the emergence of life on the primitive earth are presented.
Schneider, T; Rübben, H
2004-03-01
Phytotherapy of BPS has a long tradition in Germany; nevertheless, data referring to single phytotherapeutic agents are rare. We therefore performed a randomized, double-blind, placebo-controlled multicenter study for 1 year with Bazoton uno (459 mg dry extract of stinging nettle roots) with 246 patients. The IPSS decreased on average from 18.7+/-0.3 to 13.0+/-0.5 with a statistically significant difference compared to placebo (18.5+/-0.3 to 13.8+/-0.5; p=0.0233). The median Q(max) increased by 3.0+/-0.4 ml/s in comparison to 2.9+/-0.4 ml/s (placebo), thus not statistically significantly different, as well as the median volume of residual urine, which changed from 35.5+/-3.4 ml before therapy to 20.0+/-2.8 ml and from 40.0+/-4.0 ml to 21.0+/-2.9 ml under placebo application. The number of adverse events (29/38) as well as urinary infections etc. (3/10 events) was smaller under Bazoton uno therapy compared to placebo. Treatment with Bazoton uno can therefore be considered a safe therapeutic option for BPS, especially for reducing irritative symptoms and BPS-associated complications due to the postulated antiphlogistic and antiproliferative effects of the stinging nettle extract. A strong increase of Q(max) or reduction of residual urine are not to be expected.
Müller, Silke; März, Reinhard; Schmolz, Manfred; Drewelow, Bernd; Eschmann, Klaus; Meiser, Peter
2013-02-01
Bromelain has been used for treatment of inflammatory diseases for decades. However, the exact mechanism of action remains poorly understood. While in vitro investigations have shown conflicting effects on the release of various cytokines, no in vivo data were available. In this study, the effects on inflammation-related cytokines of two doses of bromelain were tested in a single dose placebo-controlled 3 × crossover randomized clinical trial. Cytokine circadian profiles were used to investigate the effects of bromelain on the human immune system by using stimulated whole-blood leukocytes. The effects seen in these cultures demonstrated a significant shift in the circadian profiles of the Th1 cell mediator interferon gamma (IFNγ; p < 0.043) after bromelain 3000 FIP (Fédération Internationale Pharmaceutique) units, and trends in those of the Th2-type cytokine IL-5 as well as the immunosuppressive cytokine interleukin (IL)-10. This suggests a general effect on the antigen-specific (T cell) compartment of the human immune system. This is the first time that bromelain has been shown to modulate the cellular responses of lymphocyte after oral use. It is postulated that the immunomodulating effect of bromelain observed in this trial is part of its known antiinflammatory activities. Further investigations will be necessary to verify the relevance of these findings to a diseased immune system. Copyright © 2012 John Wiley & Sons, Ltd.
Sofu, Tanju
2015-04-01
The thermal, mechanical, and neutronic performance of the metal alloy fast reactor fuel design complements the safety advantages of the liquid metal cooling and the pool-type primary system. Together, these features provide large safety margins in both normal operating modes and for a wide range of postulated accidents. In particular, they maximize the measures of safety associated with inherent reactor response to unprotected, double-fault accidents, and to minimize risk to the public and plant investment. High thermal conductivity and high gap conductance play the most significant role in safety advantages of the metallic fuel, resulting in a flatter radial temperaturemore » profile within the pin and much lower normal operation and transient temperatures in comparison to oxide fuel. Despite the big difference in melting point, both oxide and metal fuels have a relatively similar margin to melting during postulated accidents. When the metal fuel cladding fails, it typically occurs below the coolant boiling point and the damaged fuel pins remain coolable. Metal fuel is compatible with sodium coolant, eliminating the potential of energetic fuel--coolant reactions and flow blockages. All these, and the low retained heat leading to a longer grace period for operator action, are significant contributing factors to the inherently benign response of metallic fuel to postulated accidents. This paper summarizes the past analytical and experimental results obtained in past sodium-cooled fast reactor safety programs in the United States, and presents an overview of fuel safety performance as observed in laboratory and in-pile tests.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sofu, Tanju
2015-04-01
The thermal, mechanical, and neutronic performance of the metal alloy fast reactor fuel design complements the safety advantages of the liquid metal cooling and the pool-type primary system. Together, these features provide large safety margins in both normal operating modes and for a wide range of postulated accidents. In particular, they maximize the measures of safety associated with inherent reactor response to unprotected, double-fault accidents, and to minimize risk to the public and plant investment. High thermal conductivity and high gap conductance play the most significant role in safety advantages of the metallic fuel, resulting in a flatter radial temperaturemore » profile within the pin and much lower normal operation and transient temperatures in comparison to oxide fuel. Despite the big difference in melting point, both oxide and metal fuels have a relatively similar margin to melting during postulated accidents. When the metal fuel cladding fails, it typically occurs below the coolant boiling point and the damaged fuel pins remain cool-able. Metal fuel is compatible with sodium coolant, eliminating the potential of energetic fuel coolant reactions and flow blockages. All these, and the low retained heat leading to a longer grace period for operator action, are significant contributing factors to the inherently benign response of metallic fuel to postulated accidents. This paper summarizes the past analytical and experimental results obtained in past sodium-cooled fast reactor safety programs in the United States, and presents an overview of fuel safety performance as observed in laboratory and in-pile tests.« less
Llorca, Marta; Badia-Fabregat, Marina; Rodríguez-Mozaz, Sara; Caminal, Glòria; Vicent, Teresa; Barceló, Damià
2017-10-01
The removal of 27 endocrine-disrupting compounds and related compounds (suspect effect) from a reverse osmosis concentrate using an alternative decontamination method based on a fungal treatment involving Trametes versicolor was assessed. In addition to chemical analysis, the toxicity of the treated water during the treatment was monitored using a bioluminescence inhibition test and estrogenic and anti-estrogenic tests. The compounds 1H-benzotriazole (BTZ) and two tolyltriazoles (TTZs), 4-methyl-1H-benzotriazole (4-MBTZ) and 5-methyl-1H-benzotriazole (5-MBTZ), were present in the reverse osmosis concentrate at the highest concentrations (7.4 and 12.8 μg L -1 , respectively) and were partially removed by the fungal treatment under sterile conditions (58% for BTZ and 92% for TTZs) and non-sterile conditions, although to lesser extents (32% for BTZ and 50% for TTZs). Individual biotransformation studies of BTZ and the TTZs by T. versicolor in a synthetic medium and further analysis via on-line turbulent flow chromatography coupled to an HRMS-Orbitrap allowed the tentative identification of the transformation products (TPs). Six TPs were postulated for BTZ, two TPs were postulated for 4-MBTZ, and four TPs were postulated for 5-MBTZ. Most of these TPs are suggested to have been generated by conjugation with some sugars and via the methylation of the triazole group. Only TP 148 A, postulated to be derived from the biotransformation of BTZ, was observed in the effluent of the bioreactor treating the reverse osmosis concentrate. Copyright © 2017 Elsevier Ltd. All rights reserved.
Economic modelling with low-cognition agents
NASA Astrophysics Data System (ADS)
Ormerod, Paul
2006-10-01
The standard socio-economic model (SSSM) postulates very considerable cognitive powers on the part of its agents. They are able to gather all relevant information in any given situation, and to take the optimal decision on the basis of it, given their tastes and preferences. This behavioural rule is postulated to be universal. The concept of bounded rationality relaxes this somewhat, by permitting agents to have access to only limited amounts of information. But agents still optimise subject to their information set and tastes. Empirical work in economics over the past 20 years or so has shown that in general these behavioural postulates lack empirical validity. Instead, agents appear to have limited ability to gather information, and use simple rules of thumb to process the information which they have in order to take decisions. Building theoretical models on these realistic foundations which give better accounts of empirical phenomena than does the SSSM is an important challenge to both economists and econophysicists. Considerable progress has already been made in a short space of time, and examples are given in this paper.
Animal models of Helicobacter-induced disease: methods to successfully infect the mouse.
Taylor, Nancy S; Fox, James G
2012-01-01
Animal models of microbial diseases in humans are an essential component for determining fulfillment of Koch's postulates and determining how the organism causes disease, host response(s), disease prevention, and treatment. In the case of Helicobacter pylori, establishing an animal model to fulfill Koch's postulates initially proved so challenging that out of frustration a human volunteer undertook an experiment to become infected with H. pylori and to monitor disease progression in order to determine if it did cause gastritis. For the discovery of the organism and his fulfillment of Koch's postulates he and a colleague were awarded the Nobel Prize in Medicine. After H. pylori was established as a gastric pathogen, it took several years before a model was developed in mice, opening the study of the organism and its pathogenicity to the general scientific community. However, while the model is widely utilized, there are a number of difficulties that can arise and need to be overcome. The purpose of this chapter is to raise awareness regarding the problems, and to offer reliable protocols for successfully establishing the H. pylori mouse model.
Operational Axioms for Quantum Mechanics
DOE Office of Scientific and Technical Information (OSTI.GOV)
D'Ariano, Giacomo Mauro; Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL 60208
2007-02-21
The mathematical formulation of Quantum Mechanics in terms of complex Hilbert space is derived for finite dimensions, starting from a general definition of physical experiment and from five simple Postulates concerning experimental accessibility and simplicity. For the infinite dimensional case, on the other hand, a C*-algebra representation of physical transformations is derived, starting from just four of the five Postulates via a Gelfand-Naimark-Segal (GNS) construction. The present paper simplifies and sharpens the previous derivation in Ref. [1]. The main ingredient of the axiomatization is the postulated existence of faithful states that allows one to calibrate the experimental apparatus. Such notionmore » is at the basis of the operational definitions of the scalar product and of the transposed of a physical transformation. What is new in the present paper with respect to Ref. [1], is the operational deduction of an involution corresponding to the complex-conjugation for effects, whose extension to transformations allows to define the adjoint of a transformation when the extension is composition-preserving. The existence of such composition-preserving extension among possible extensions is analyzed.« less
IS ISLAND PARK A HOT DRY ROCK SYSTEM?
Hoover, D.B.; Pierce, Herbert A.; Long, C.L.
1985-01-01
The Island Park-Yellowstone National Park region comprises a complex caldera system which has formed over the last 2 m. y. The caldera system has been estimated to contain 50% of the total thermal energy remaining in all young igneous systems in the United States. As the result of a reexamination of the data and recent electrical work in the area, the authors now postulate that much of the area where the first- and second-stage calderas developed is underlain by a solidified but still hot pluton. They postulate that the pluton represents a significant hot-dry-rock resource for the United States.
Counterfactual Definiteness and Bell's Inequality
NASA Astrophysics Data System (ADS)
Hess, Karl; Raedt, Hans De; Michielsen, Kristel
Counterfactual definiteness must be used as at least one of the postulates or axioms that are necessary to derive Bell-type inequalities. It is considered by many to be a postulate that is not only commensurate with classical physics (as for example Einstein's special relativity), but also separates and distinguishes classical physics from quantum mechanics. It is the purpose of this paper to show that Bell's choice of mathematical functions and independent variables implicitly includes counterfactual definiteness and reduces the generality of the physics of Bell-type theories so significantly that no meaningful comparison of these theories with actual Einstein-Podolsky-Rosen experiments can be made.
A coupled problem of finite deformation and flow in porous media
NASA Astrophysics Data System (ADS)
Moussa, A. B.
1980-06-01
A theory for deformation and two phase flow in porous media was developed. Equations of balance of mass, momentum, moment of momentum and energy for each constituent were postulated. These led to equivalent balance equations for the mixture as a whole to which an entropy production inequality was also postulated. The formulation was then applied to the silage material. A constitutive theory was developed for the mixture. General appropriate constitutive assumptions were suggested and made to satisfy the axiom of material objectivity and entropy production inequality. Material incompressibility was defined and introduced into the general form of constitutive relations.
The Measurement Process in the Generalized Contexts Formalism for Quantum Histories
NASA Astrophysics Data System (ADS)
Losada, Marcelo; Vanni, Leonardo; Laura, Roberto
2016-02-01
In the interpretations of quantum mechanics involving quantum histories there is no collapse postulate and the measurement is considered as a quantum interaction between the measured system and the measured instrument. For two consecutive non ideal measurements on the same system, we prove that both pointer indications at the end of each measurement are compatible properties in our generalized context formalism for quantum histories. Inmediately after the first measurement an effective state for the measured system is deduced from the formalism, generalizing the state that would be obtained by applying the state collapse postulate.
Radioactivity in fossils at the Hagerman Fossil Beds National Monument.
Farmer, C Neal; Kathren, Ronald L; Christensen, Craig
2008-08-01
Since 1996, higher than background levels of naturally occurring radioactivity have been documented in both fossil and mineral deposits at Hagerman Fossil Beds National Monument in south-central Idaho. Radioactive fossil sites occur primarily within an elevation zone of 900-1000 m above sea level and are most commonly found associated with ancient river channels filled with sand. Fossils found in clay rich deposits do not exhibit discernable levels of radioactivity. Out of 300 randomly selected fossils, approximately three-fourths exhibit detectable levels of natural radioactivity ranging from 1 to 2 orders of magnitude above ambient background levels when surveyed with a portable hand held Geiger-Muller survey instrument. Mineral deposits in geologic strata also show above ambient background levels of radioactivity. Radiochemical lab analysis has documented the presence of numerous natural radioactive isotopes. It is postulated that ancient groundwater transported radioactive elements through sand bodies containing fossils which precipitated out of solution during the fossilization process. The elevated levels of natural radioactivity in fossils may require special precautions to ensure that exposures to personnel from stored or displayed items are kept as low as reasonably achievable (ALARA).
Ideas of Flat and Curved Space in History of Physics
NASA Astrophysics Data System (ADS)
Berezin, Alexander A.
2006-04-01
Since ``everything which is not prohibited is compulsory'' (assigned to Gell-Mann) we can postulate infinite flat Cartesian N-dimensional (N: any integer) space-time (ST) as embedding for any curved ST. Ergodicity raises quest of whether total number of inflationary and/or Everett bubbles (mini-verses) is finite, countably infinite (aleph-zero) or uncountably infinite (aleph-one). Are these bubbles form Gaussian distribution or form some non-random subsetting? Perhaps, communication between mini-verses (idea of D.Deutsch) can be facilitated by a kind of minimax non-local dynamics akin to Fermat principle? (Minimax Principle in Bubble Cosmology). Even such classical effects as magnetism and polarization have some non-local features. Can we go below the Planck length to perhaps Compton wavelength of our ``Hubble's bubble'' (h/Mc = 10 to minus 95 m, if M = 10 to 54 kg)? When talking about time loops and ergodicity (eternal return paradigm) is there some hysterisis in the way quantum states are accessed in ``forward'' or ``reverse'' direction? (reverse direction implies backward causality of J.Wheeler and/or Aristotelian final causation).
NASA Astrophysics Data System (ADS)
Hanapi, Wan Nurhidayah Wan; Iuan-Sheau, Chin; Mahadi, Nor Muhammad; Murad, Abdul Munir Abdul; Bakar, Farah Diba Abu
2015-09-01
Cutinase is an important biocatalyst for various industrial applications. This enzyme which has dual functionality comparable to esterases and lipases, is efficient in the hydrolysis of soluble esters and emulsified triacylglycerols. Naturally-occurring enzymes usually have disadvantages when applied in non-natural catalysis due to Glomerella cingulata cutinase enzyme thermostability. It is postulated that by increasing the rigidity at certain amino acid positions showing high mobility based on the three-dimensional structure of G. cingulata cutinase, the improvement in thermostability will be achieved. The amino acid N82 of G. cingulata cutinase was selected based on its high B-factor value determined via the B-FITTER program. Megaprimer PCR was employed to introduce mutations at the chosen site by randomization using NNK degenerate primers. About 300 transformants were selected for screening of positive cutinase variants. The N82_V14 cutinase variant was observed to be more thermostable at an almost 2-fold increase when exposed at 50°C for 1 hr as compared to the wild-type enzyme. This study may provide valuable information regarding thermal stability of cutinases denaturation at high temperatures.
Attentional bias modification encourages healthy eating.
Kakoschke, Naomi; Kemps, Eva; Tiggemann, Marika
2014-01-01
The continual exposure to unhealthy food cues in the environment encourages poor dietary habits, in particular consuming too much fat and sugar, and not enough fruit and vegetables. According to Berridge's (2009) model of food reward, unhealthy eating is a behavioural response to biased attentional processing. The present study used an established attentional bias modification paradigm to discourage the consumption of unhealthy food and instead promote healthy eating. Participants were 146 undergraduate women who were randomly assigned to two groups: one was trained to direct their attention toward pictures of healthy food ('attend healthy' group) and the other toward unhealthy food ('attend unhealthy' group). It was found that participants trained to attend to healthy food cues demonstrated an increased attentional bias for such cues and ate relatively more of the healthy than unhealthy snacks compared to the 'attend unhealthy' group. Theoretically, the results support the postulated link between biased attentional processing and consumption (Berridge, 2009). At a practical level, they offer potential scope for interventions that focus on eating well. Copyright © 2013 Elsevier Ltd. All rights reserved.
Direct observation of molecular cooperativity near the glass transition.
Russell, E V; Israeloff, N E
2000-12-07
The increasingly sluggish response of a supercooled liquid as it nears its glass transition (for example, refrigerated honey) is prototypical of glassy dynamics found in proteins, neural networks and superconductors. The notion that molecules rearrange cooperatively has long been postulated to explain diverging relaxation times and broadened (non-exponential) response functions near the glass transition. Recently, cooperativity was observed and analysed in colloid glasses and in simulations of binary liquids well above the glass transition. But nanometre-scale studies of cooperativity at the molecular glass transition are lacking. Important issues to be resolved include the precise form of the cooperativity and its length scale, and whether the broadened response is intrinsic to individual cooperative regions, or arises only from heterogeneity in an ensemble of such regions. Here we describe direct observations of molecular cooperativity near the glass transition in polyvinylacetate (PVAc), using nanometre-scale probing of dielectric fluctuations. Molecular clusters switched spontaneously among two to four distinct configurations, producing random telegraph noise. Our analysis of these noise signals and their power spectra reveals that individual clusters exhibit transient dynamical heterogeneity and non-exponential kinetics.
NASA Technical Reports Server (NTRS)
Storrie-Lombardi, Michael C.; Hoover, Richard B.
2005-01-01
Last year we presented techniques for the detection of fossils during robotic missions to Mars using both structural and chemical signatures[Storrie-Lombardi and Hoover, 2004]. Analyses included lossless compression of photographic images to estimate the relative complexity of a putative fossil compared to the rock matrix [Corsetti and Storrie-Lombardi, 2003] and elemental abundance distributions to provide mineralogical classification of the rock matrix [Storrie-Lombardi and Fisk, 2004]. We presented a classification strategy employing two exploratory classification algorithms (Principal Component Analysis and Hierarchical Cluster Analysis) and non-linear stochastic neural network to produce a Bayesian estimate of classification accuracy. We now present an extension of our previous experiments exploring putative fossil forms morphologically resembling cyanobacteria discovered in the Orgueil meteorite. Elemental abundances (C6, N7, O8, Na11, Mg12, Ai13, Si14, P15, S16, Cl17, K19, Ca20, Fe26) obtained for both extant cyanobacteria and fossil trilobites produce signatures readily distinguishing them from meteorite targets. When compared to elemental abundance signatures for extant cyanobacteria Orgueil structures exhibit decreased abundances for C6, N7, Na11, All3, P15, Cl17, K19, Ca20 and increases in Mg12, S16, Fe26. Diatoms and silicified portions of cyanobacterial sheaths exhibiting high levels of silicon and correspondingly low levels of carbon cluster more closely with terrestrial fossils than with extant cyanobacteria. Compression indices verify that variations in random and redundant textural patterns between perceived forms and the background matrix contribute significantly to morphological visual identification. The results provide a quantitative probabilistic methodology for discriminating putatitive fossils from the surrounding rock matrix and &om extant organisms using both structural and chemical information. The techniques described appear applicable to the geobiological analysis of meteoritic samples or in situ exploration of the Mars regolith. Keywords: cyanobacteria, microfossils, Mars, elemental abundances, complexity analysis, multifactor analysis, principal component analysis, hierarchical cluster analysis, artificial neural networks, paleo-biosignatures
Joulaei, Mohammad; Bahari, Mahmoud; Ahmadi, Anahid; Savadi Oskoee, Siavash
2012-01-01
Background and aims Effect of surface treatments on repair bond strength of aged composite resins might be different due to their dissimilar fillers. The aim was to evaluate the effect of different surface treatments on repair micro-shear bond strength (µSBS) of silica- (Spectrum TPH) and zirconia-filled (Filtek Z250) composite resins. Materials and methods Twenty-seven composite resin blocks were made from each type of composite resin: Z250 and Spectrum TPH. After aging, blocks of each type were randomly divided into three groups according to surface treatments: alloy primer, silane, and only surface roughening. Subsequently, each group was further subdivided into 3 subgroups based on the adhesive system used: Single Bond, Clearfil SE Bond, and Margin Bond. Four composite resin columns were added on each block. After thermocycling, µSBStest were done at cross head speed of 0.5 mm/min. Data was analysed using multifactor ANOVA, one-way ANOVA and a post-hoc Bonferroni tests (α = 0.05). Results Analysis of data showed that the effect of composite resin type was not significant (p > 0.05), but the effects of the type of surface treatment (p = 0.01) and the type of adhesive system (p = 0.01) were significant on repair µSBS. In addition, the cumulative effect of the composite type-surface treatment and the composite type with the type of adhesive system were not statistically significant (p > 0.05). However, the cumulative effects of the adhesive system-surface treatment (p = 0.03) and the composite type-the adhesive system-surface treatments (p = 0.002) were significant. Conclusion Although repair µSBS values of both silica- and zirconia-filled composite resins were similar, use of different combinations of surface treatments and adhesive systems affected their repair µSBS differently. PMID:23277859
Fulfilling Koch's postulates in glycoscience: HCELL, GPS and translational glycobiology.
Sackstein, Robert
2016-06-01
Glycoscience-based research that is performed expressly to address medical necessity and improve patient outcomes is called "translational glycobiology". In the 19th century, Robert Koch proposed a set of postulates to rigorously establish causality in microbial pathogenesis, and these postulates can be reshaped to guide knowledge into how naturally-expressed glycoconjugates direct molecular processes critical to human well-being. Studies in the 1990s indicated that E-selectin, an endothelial lectin that binds sialofucosylated carbohydrate determinants, is constitutively expressed on marrow microvessels, and investigations in my laboratory indicated that human hematopoietic stem cells (HSCs) uniquely express high levels of a specialized glycoform of CD44 called "hematopoietic cell E-/L-selectin ligand" (HCELL) that functions as a highly potent E-selectin ligand. To assess the role of HCELL in directing HSC migration to marrow, a method called "glycosyltransferase-programmed stereosubstitution" (GPS) was developed to custom-modify CD44 glycans to enforce HCELL expression on viable cell surfaces. Human mesenchymal stem cells (MSCs) are devoid of E-selectin ligands, but GPS-based glycoengineering of CD44 on MSCs licenses homing of these cells to marrow in vivo, providing direct evidence that HCELL serves as a "bone marrow homing receptor". This review will discuss the molecular basis of cell migration in historical context, will describe the discovery of HCELL and its function as the bone marrow homing receptor, and will inform on how glycoengineering of CD44 serves as a model for adapting Koch's postulates to elucidate the key roles that glycoconjugates play in human biology and for realizing the immense impact of translational glycobiology in clinical medicine. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Randhawa, Mandeep; Bansal, Urmil; Lillemo, Morten; Miah, Hanif; Bariana, Harbans
2016-11-01
Wild relatives, landraces and cultivars from different geographical regions have been demonstrated as the sources of genetic variation for resistance to rust diseases. This study involved assessment of diversity for resistance to three rust diseases among a set of Nordic spring wheat cultivars. These cultivars were tested at the seedling stage against several pathotypes of three rust pathogens in the greenhouse. All stage stem rust resistance genes Sr7b, Sr8a, Sr12, Sr15, Sr17, Sr23 and Sr30, and leaf rust resistance genes Lr1, Lr3a, Lr13, Lr14a, Lr16 and Lr20 were postulated either singly or in different combinations among these cultivars. A high proportion of cultivars were identified to carry linked rust resistance genes Sr15 and Lr20. Although 51 cultivars showed variation against Puccinia striiformis f. sp. tritici (Pst) pathotypes used in this study, results were not clearly contrasting to enable postulation of stripe rust resistance genes in these genotypes. Stripe rust resistance gene Yr27 was postulated in four cultivars and Yr1 was present in cultivar Zebra. Cultivar Tjalve produced low stripe rust response against all Pst pathotypes indicating the presence either of a widely effective resistance gene or combination of genes with compensating pathogenic specificities. Several cultivars carried moderate to high level of APR to leaf rust and stripe rust. Seedling stem rust susceptible cultivar Aston exhibited moderately resistant to moderately susceptible response, whereas other cultivars belonging to this class were rated moderately susceptible or higher. Molecular markers linked with APR genes Yr48, Lr34/Yr18/Sr57, Lr68 and Sr2 detected the presence of these genes in some genotypes.
Li, Yuanyuan; Xie, Yanming; Fu, Yingkun
2011-10-01
Currently massive researches have been launched about the safety, efficiency and economy of post-marketing Chinese patent medicine (CPM) proprietary Chinese medicine, but it was lack of a comprehensive interpretation. Establishing the risk evaluation index system and risk assessment model of CPM is the key to solve drug safety problems and protect people's health. The clinical risk factors of CPM exist similarities with the Western medicine, can draw lessons from foreign experience, but also have itself multi-factor multivariate multi-level complex features. Drug safety risk assessment for the uncertainty and complexity, using analytic hierarchy process (AHP) to empower the index weights, AHP-based fuzzy neural network to build post-marketing CPM risk evaluation index system and risk assessment model and constantly improving the application of traditional Chinese medicine characteristic is accord with the road and feasible beneficial exploration.
Web based aphasia test using service oriented architecture (SOA)
NASA Astrophysics Data System (ADS)
Voos, J. A.; Vigliecca, N. S.; Gonzalez, E. A.
2007-11-01
Based on an aphasia test for Spanish speakers which analyze the patient's basic resources of verbal communication, a web-enabled software was developed to automate its execution. A clinical database was designed as a complement, in order to evaluate the antecedents (risk factors, pharmacological and medical backgrounds, neurological or psychiatric symptoms, brain injury -anatomical and physiological characteristics, etc) which are necessary to carry out a multi-factor statistical analysis in different samples of patients. The automated test was developed following service oriented architecture and implemented in a web site which contains a tests suite, which would allow both integrating the aphasia test with other neuropsychological instruments and increasing the available site information for scientific research. The test design, the database and the study of its psychometric properties (validity, reliability and objectivity) were made in conjunction with neuropsychological researchers, who participate actively in the software design, based on the patients or other subjects of investigation feedback.
Biomimetic Delivery with Micro- and Nanoparticles
Balmert, Stephen C.; Little, Steven R.
2013-01-01
The nascent field of biomimetic delivery with micro- and nanoparticles (MNP) has advanced considerably in recent years. Drawing inspiration from the ways that cells communicate in the body, several different modes of “delivery” (i.e. temporospatial presentation of biological signals) have been investigated in a number of therapeutic contexts. In particular, this review focuses on (1) controlled release formulations that deliver natural soluble factors with physiologically relevant temporal context, (2) presentation of surface-bound ligands to cells, with spatial organization of ligands ranging from isotropic to dynamically anisotropic, and (3) physical properties of particles, including size, shape and mechanical stiffness, which mimic those of natural cells. Importantly, the context provided by multimodal, or multifactor delivery represents a key element of most biomimetic MNP systems, a concept illustrated by an analogy to human interpersonal communication. Regulatory implications of increasingly sophisticated and “cell-like” biomimetic MNP systems are also discussed. PMID:22528985
Lu, Yang; Chen, Bo; Yu, Miao; Han, Juan; Wang, Yun; Tan, Zhenjiang; Yan, Yongsheng
2016-11-01
Smart polymer aqueous two phase flotation system (SPATPF) is a new separation and enrichment technology that integrated the advantages of the three technologies, i.e., aqueous two phase system, smart polymer and flotation sublation. Ethylene oxide and propylene oxide copolymer (EOPO)-(NH4)2SO4 SPATPF is a pretreatment technique, and it is coupled with high-performance liquid chromatography to analyze the trace ciprofloxacin and lomefloxacin in real food samples. The optimized conditions of experiment were determined in the multi-factor experiment by using response surface methodology. The flotation efficiency of lomefloxacin and ciprofloxacin was 94.50% and 98.23% under the optimized conditions. The recycling experimentsshowed that the smart polymer EOPO could use repeatedly, which will reduce the cost in the future application. Copyright © 2016 Elsevier Ltd. All rights reserved.
Zuffo, Riccardo Giorgio; Ferretti, Maria Santa
2012-01-01
INTRODUCTION. The aim of the present study is to demonstrate the validity of the MOSRQ, a questionnaire for the assessment of work related stress risk. This questionnaire has 38 items: 19 related to organizational stressors and 19 to strains. Firstly, it was performed a critical analysis of instruments reported in scientific literature; then relevant items about sources and consequences of work related stress were selected in order to obtain the questionnaire. Finally MOSRQ was administered to a sample of 2314 subjects mainly employed in private firms belonging to industry and service sectors. MOSRQ obtains a good index of reliability (alpha = .89 for organizational stressor/antecedents and alpha = .92 for strain/outcome). Factor analysis presents a structure with 3 factors both for the antecedents and for the outcomes of work related stress. In conclusion, it is claimed that MOSRQ has the necessary psychometric characteristics for use in research as well as in organizational contexts.
Brown, Michael
2008-01-01
Summary Eighteenth- and early nineteenth-century ideas about the occurrence and spread of epidemic disease were complex and contested. Although many thought that diseases such as plague, typhus, and cholera were contagious and were communicated from person to person or via the medium of goods, others believed that they were the product of atmospheric change. Moreover, as historians have emphasized, the early nineteenth century saw a move from a multifactoral, climatic etiology toward one that prioritized specific local corruption of the atmosphere caused by putrefying animal and vegetable matter. In this paper, I extend this analysis by linking to recent literature on dirt and disgust and exploring the importance of theologies. I examine the work of two key figures in the history of British epidemiology, Charles Maclean and Thomas Southwood Smith, and demonstrate how the latter's increasing emphasis upon the causal agency of filth was structured by his Unitarian faith and his belief in a universally benevolent God. PMID:18791295
Physician leadership styles and effectiveness: an empirical study.
Xirasagar, Sudha; Samuels, Michael E; Stoskopf, Carleen H
2005-12-01
The authors study the association between physician leadership styles and leadership effectiveness. Executive directors of community health centers were surveyed (269 respondents; response rate = 40.9 percent) for their perceptions of the medical director's leadership behaviors and effectiveness, using an adapted Multifactor Leadership Questionnaire (43 items on a 0-4 point Likert-type scale), with additional questions on demographics and the center's clinical goals and achievements. The authors hypothesize that transformational leadership would be more positively associated with executive directors' ratings of effectiveness, satisfaction with the leader, and subordinate extra effort, as well as the center's clinical goal achievement, than transactional or laissez-faire leadership. Separate ordinary least squares regressions were used to model each of the effectiveness measures, and general linear model regression was used to model clinical goal achievement. Results support the hypothesis and suggest that physician leadership development using the transformational leadership model may result in improved health care quality and cost control.
[Review of research design and statistical methods in Chinese Journal of Cardiology].
Zhang, Li-jun; Yu, Jin-ming
2009-07-01
To evaluate the research design and the use of statistical methods in Chinese Journal of Cardiology. Peer through the research design and statistical methods in all of the original papers in Chinese Journal of Cardiology from December 2007 to November 2008. The most frequently used research designs are cross-sectional design (34%), prospective design (21%) and experimental design (25%). In all of the articles, 49 (25%) use wrong statistical methods, 29 (15%) lack some sort of statistic analysis, 23 (12%) have inconsistencies in description of methods. There are significant differences between different statistical methods (P < 0.001). The correction rates of multifactor analysis were low and repeated measurement datas were not used repeated measurement analysis. Many problems exist in Chinese Journal of Cardiology. Better research design and correct use of statistical methods are still needed. More strict review by statistician and epidemiologist is also required to improve the literature qualities.
O'Neill, Liam; Dexter, Franklin
2005-11-01
We compare two techniques for increasing the transparency and face validity of Data Envelopment Analysis (DEA) results for managers at a single decision-making unit: multifactor efficiency (MFE) and non-radial super-efficiency (NRSE). Both methods incorporate the slack values from the super-efficient DEA model to provide a more robust performance measure than radial super-efficiency scores. MFE and NRSE are equivalent for unique optimal solutions and a single output. MFE incorporates the slack values from multiple output variables, whereas NRSE does not. MFE can be more transparent to managers since it involves no additional optimization steps beyond the DEA, whereas NRSE requires several. We compare results for operating room managers at an Iowa hospital evaluating its growth potential for multiple surgical specialties. In addition, we address the problem of upward bias of the slack values of the super-efficient DEA model.
Boj, J; Hernandez, M; Espasa, E; Espanya, A
2014-01-01
Mouth and oropharynx cancer constitute 5% of all malignancies; 95% of them are head and neck squamous cell carcinomas. Carcinogenesis is a multifactor process. Mutagenesis is also determined by the human papilloma virus which has recently been found to be etiologically associated with 20 to 25% of head and neck squamous cell carcinomas, mostly in the oropharinx. Focal fibrous hyperplasia of the connective tissue comes up as an answer to a chronic irritation in which a big amount of collagen can be found. As there exist certain clinical resemblance between squamous cell papilloma, fibrous focal hyperplasia and other mesenchimal tumors it is recommended to proceed, always, with removal and study. Two cases, one of an oral papilloma and another of a focal fibrous hyperplasia in pediatric patients, treated with an Er,Cr:YSGG laser wave length (mu) of 2780 nm are presented.
Anthropology and style of life in middle age women.
Prado Martinez, Consuelo; Diaz, María Elena; Toledo, Emilia María; Carmenate, María Margarita; Wong, Iraida; Moreno, Raisa; Moreno, Vilma
2003-06-01
The anthropometric pattern, demographics data, lifestyle factors and several aspects of morbidity were analyzed for 400 Cuban women ages 40-60 years. More than 85% of women were obese, being these in direct association with morphology typically androgens, more evident in the postmenopausal women. In these women observed less body mass index and overweight, in an equivalent way between pre and postmenopausal women. A moderate consumption of rice, was evidenced, pastas and vegetables, few candies and fatty, what points to or quite acceptable knowledge of the harmful effect of some foods, to weigh that the shadowy use of saturated fats and not saturated it was the most frequent thing. By multifactor approach it is possible to make relation between nutritional patterns, morphology and climacteric symptoms; Cuban women present a different frequencies from an other literature showing the risk of generalist this studies and health's actions.
2011-08-08
This final rule updates the payment rates used under the prospective payment system for skilled nursing facilities (SNFs) for fiscal year 2012. In addition, it recalibrates the case-mix indexes so that they more accurately reflect parity in expenditures between RUG-IV and the previous case-mix classification system. It also includes a discussion of a Non-Therapy Ancillary component currently under development within CMS. In addition, this final rule discusses the impact of certain provisions of the Affordable Care Act, and reduces the SNF market basket percentage by the multi-factor productivity adjustment. This rule also implements certain changes relating to the payment of group therapy services and implements new resident assessment policies. Finally, this rule announces that the proposed provisions regarding the ownership disclosure requirements set forth in section 6101 of the Affordable Care Act will be finalized at a later date.
NASA Astrophysics Data System (ADS)
Lei, Mingfeng; Lin, Dayong; Liu, Jianwen; Shi, Chenghua; Ma, Jianjun; Yang, Weichao; Yu, Xiaoniu
2018-03-01
For the purpose of investigating lining concrete durability, this study derives a modified chloride diffusion model for concrete based on the odd continuation of boundary conditions and Fourier transform. In order to achieve this, the linear stress distribution on a sectional structure is considered, detailed procedures and methods are presented for model verification and parametric analysis. Simulation results show that the chloride diffusion model can reflect the effects of linear stress distribution of the sectional structure on the chloride diffusivity with reliable accuracy. Along with the natural environmental characteristics of practical engineering structures, reference value ranges of model parameters are provided. Furthermore, a chloride diffusion model is extended for the consideration of multi-factor coupling of linear stress distribution, chloride concentration and diffusion time. Comparison between model simulation and typical current research results shows that the presented model can produce better considerations with a greater universality.
[The antibacterial immunity of people under dynamic observation in an altered radiation situation].
Bidnenko, S I; Nazarchuk, L V; Fedorovskaia, E A; Liutko, O B; Open'ko, L B
1992-01-01
The comparative study of the isolation rate, level, antigenic and class specificity of serum antibodies to the causative agents of purulent septic infections (Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis) and acute enteric infections in healthy adults with different ABO blood groups before (836 persons) and after (1,429 persons) the catastrophe at the Chernobyl nuclear power station was made. The study revealed the fact that the genesis of antibodies directed against different microorganisms can be stimulated without additional antigenic challenge in the form of disease or immunization, which was definitely indicative of the influence of small radiation doses in Kiev on the humoral immunity of the population. The multifactor character of the dependence of antibacterial antibody formation under altered radiation conditions on the specific features of the infective agent and the intensity of its circulation among the population, individual immune responsiveness of the body and concrete radiation conditions was established.
A surrogate model for thermal characteristics of stratospheric airship
NASA Astrophysics Data System (ADS)
Zhao, Da; Liu, Dongxu; Zhu, Ming
2018-06-01
A simple and accurate surrogate model is extremely needed to reduce the analysis complexity of thermal characteristics for a stratospheric airship. In this paper, a surrogate model based on the Least Squares Support Vector Regression (LSSVR) is proposed. The Gravitational Search Algorithm (GSA) is used to optimize hyper parameters. A novel framework consisting of a preprocessing classifier and two regression models is designed to train the surrogate model. Various temperature datasets of the airship envelope and the internal gas are obtained by a three-dimensional transient model for thermal characteristics. Using these thermal datasets, two-factor and multi-factor surrogate models are trained and several comparison simulations are conducted. Results illustrate that the surrogate models based on LSSVR-GSA have good fitting and generalization abilities. The pre-treated classification strategy proposed in this paper plays a significant role in improving the accuracy of the surrogate model.
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.
Violent youth groups in Indonesia: the cases of Yogyakarta and Nusa Tenggara Barat.
Kristiansen, Stein
2003-01-01
Problems of violent youth groups have escalated in Indonesia, following economic recession, unemployment, and weakened state institutions. Young people have been hit by the lack of income and broken expectations. In consequence, youth groups emerge and arrange for members' economic revenue as well as identity creation and confidence. Religion in some cases is used to legitimize violence and to strengthen the boldness of group members. The paper offers a brief overview of gangster (preman) traditions in Indonesia. Empirical findings on violent youth groups in the two selected provinces are presented within a multi-factor analytical framework, where the need for income and identity strengthening, political élite interests, and the lack of law enforcement contribute to explaining criminal and vigilante violence. Interviews with leaders and members of movements engaged in violent actions offer insights into a problem that threatens national security and control.
Boamah, Sheila A; Tremblay, Paul
2018-05-01
The Multifactor Leadership Questionnaire (MLQ) is the most widely used instrument for assessing dimensions of leadership style; yet, most studies have failed to reproduce the original MLQ factor structure. The current study evaluates the dimensionality and nomological validity of Bass's transactional and transformational leadership model using the MLQ in a sample of registered nurses working in acute care hospitals in Canada. A combination of exploratory and confirmatory factor analyses were used to evaluate the hypothetical factor structure of the MLQ consisting of five transformational factors, and three transactional factors. Results suggest that the eight-factor solution displayed best fit indices; however, two transactional factors should be extracted due to high interscale correlations and lack of differential relationships with the two leadership variables. The findings support a scale refinement and the need for new theory concerning the five transformational leadership and contingent reward dimensions of the MLQ.
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.
Multi-factor energy price models and exotic derivatives pricing
NASA Astrophysics Data System (ADS)
Hikspoors, Samuel
The high pace at which many of the world's energy markets have gradually been opened to competition have generated a significant amount of new financial activity. Both academicians and practitioners alike recently started to develop the tools of energy derivatives pricing/hedging as a quantitative topic of its own. The energy contract structures as well as their underlying asset properties set the energy risk management industry apart from its more standard equity and fixed income counterparts. This thesis naturally contributes to these broad market developments in participating to the advances of the mathematical tools aiming at a better theory of energy contingent claim pricing/hedging. We propose many realistic two-factor and three-factor models for spot and forward price processes that generalize some well known and standard modeling assumptions. We develop the associated pricing methodologies and propose stable calibration algorithms that motivate the application of the relevant modeling schemes.
Using Bayes factors for multi-factor, biometric authentication
NASA Astrophysics Data System (ADS)
Giffin, A.; Skufca, J. D.; Lao, P. A.
2015-01-01
Multi-factor/multi-modal authentication systems are becoming the de facto industry standard. Traditional methods typically use rates that are point estimates and lack a good measure of uncertainty. Additionally, multiple factors are typically fused together in an ad hoc manner. To be consistent, as well as to establish and make proper use of uncertainties, we use a Bayesian method that will update our estimates and uncertainties as new information presents itself. Our algorithm compares competing classes (such as genuine vs. imposter) using Bayes Factors (BF). The importance of this approach is that we not only accept or reject one model (class), but compare it to others to make a decision. We show using a Receiver Operating Characteristic (ROC) curve that using BF for determining class will always perform at least as well as the traditional combining of factors, such as a voting algorithm. As the uncertainty decreases, the BF result continues to exceed the traditional methods result.
Dynamic multifactor clustering of financial networks
NASA Astrophysics Data System (ADS)
Ross, Gordon J.
2014-02-01
We investigate the tendency for financial instruments to form clusters when there are multiple factors influencing the correlation structure. Specifically, we consider a stock portfolio which contains companies from different industrial sectors, located in several different countries. Both sector membership and geography combine to create a complex clustering structure where companies seem to first be divided based on sector, with geographical subclusters emerging within each industrial sector. We argue that standard techniques for detecting overlapping clusters and communities are not able to capture this type of structure and show how robust regression techniques can instead be used to remove the influence of both sector and geography from the correlation matrix separately. Our analysis reveals that prior to the 2008 financial crisis, companies did not tend to form clusters based on geography. This changed immediately following the crisis, with geography becoming a more important determinant of clustering structure.
Use of instruments to evaluate leadership in nursing and health services.
Carrara, Gisleangela Lima Rodrigues; Bernardes, Andrea; Balsanelli, Alexandre Pazetto; Camelo, Silvia Helena Henriques; Gabriel, Carmen Silvia; Zanetti, Ariane Cristina Barboza
2018-03-12
To identify the available scientific evidence about the use of instruments for the evaluation of leadership in health and nursing services and verify the use of leadership styles/models/theories in the construction of these tools. Integrative literature review of indexed studies in the LILACS, PUBMED, CINAHL and EMBASE databases from 2006 to 2016. Thirty-eight articles were analyzed, exhibiting 19 leadership evaluation tools; the most used were the Multifactor Leadership Questionnaire, the Global Transformational Leadership Scale, the Leadership Practices Inventory, the Servant Leadership Questionnaire, the Servant Leadership Survey and the Authentic Leadership Questionnaire. The literature search allowed to identify the main theories/styles/models of contemporary leadership and analyze their use in the design of leadership evaluation tools, with the transformational, situational, servant and authentic leadership categories standing out as the most prominent. To a lesser extent, the quantum, charismatic and clinical leadership types were evidenced.
NASA Astrophysics Data System (ADS)
Chen, Lin; Bai, Shu-Lin
2018-04-01
Hastelloy C22 coating was prepared on substrate of Q235 steel by high power multilayer laser cladding. The microstructure, hardness and anti-corrosion properties of coating were investigated. The corrosion tests in 3.5% NaCl solution were carried out with variation of impingement angle and velocity, and vibration frequency of sample. The microstructure of coating changes from equiaxed grain at the top surface to dendrites oriented at an angle of 60° to the substrate inside the coating. The corrosion rate of coating increases with the increase of impingement angle and velocity, and vibrant frequency of sample. Corrosion mechanisms relate to repassivation and depassivation of coating according to electrochemical measurements. Above results show that multilayer laser cladding can endow Hastelloy C22 coating with fine microstructures, high hardness and good anti-corrosion performances.
The Problem of Dualism in Modern Western Medicine
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
Analyses of the structure of group correlations in Korean financial markets
NASA Astrophysics Data System (ADS)
Ko, Jeung Su; Lim, Gyuchang; Kim, Kyungsik
2012-12-01
In this paper, we construct and analyze the structure of cross-correlations in two Korean stock markets, the Korea Composite Stock Price Index (KOSPI) and the Korea Securities Dealers Automated Quotation (KOSDAQ). We investigate a remarkable agreement between the theoretical prediction and the empirical data concerning the density of eigenvalues in the KOSPI and the KOSDAQ. We estimate daily cross-correlations with respect to price fluctuations of 629 KOSPI and 650 KOSDAQ stock entities for the period from 2006 to 2010. The research for the structure of group correlations undress the market-wide effect by using the Markowitz multi-factor model and network-based approach. We find stock entities that involve the same business sectors and verify the structure of group correlations by applying a network-based approach. In particular, the KOSPI has a dense correlation besides overall group correlations for stock entities, whereas both correlations are less for the KOSDAQ than for the KOSPI.
A GIS-based approach for comparative analysis of potential fire risk assessment
NASA Astrophysics Data System (ADS)
Sun, Ying; Hu, Lieqiu; Liu, Huiping
2007-06-01
Urban fires are one of the most important sources of property loss and human casualty and therefore it is necessary to assess the potential fire risk with consideration of urban community safety. Two evaluation models are proposed, both of which are integrated with GIS. One is the single factor model concerning the accessibility of fire passage and the other is grey clustering approach based on the multifactor system. In the latter model, fourteen factors are introduced and divided into four categories involving security management, evacuation facility, construction resistance and fire fighting capability. A case study on campus of Beijing Normal University is presented to express the potential risk assessment models in details. A comparative analysis of the two models is carried out to validate the accuracy. The results are approximately consistent with each other. Moreover, modeling with GIS promotes the efficiency the potential risk assessment.
Leadership styles of nurse managers in a multinational environment.
Suliman, Wafika A
2009-01-01
This is a descriptive study conducted at a multinational working environment, where 1500 nurses representing 52 nationalities are employed. The study aimed at exploring the predominant leadership style of nurse managers through self-evaluation and staff nurses' evaluation and the impact of working in a multinational environment on their intention to stay or quit. The value lies in its focus on leadership styles in an environment where national diversity among managers, staff, and patients is very challenging. The study included 31 nurse managers and 118 staff nurses using Bass and Avolio's (1995) Multifactor Leadership Questionnaire. The results showed that nurse managers and staff nurses reported transformational leadership as predominant with significant difference in favor of nurse managers. Participants' nationality and intention to stay or quit affected their perception of transformational leadership as a predominant style. The implications highlight the need for senior nursing management to set effective retention strategies for transformational nurse managers who work at multinational environments.
The relationship between leadership styles and empathy among student nurses.
Gunther, Mary; Evans, Ginger; Mefford, Linda; Coe, Thomas R
2007-01-01
Much of the nursing literature on leadership describes the qualities of existing nursing leaders, while emphasizing the need for leadership development in student nurses for both managerial and clinical practice. However, there is a lack of research literature on the characteristics of current students. Conducted by the University of Tennessee College of Nursing Empathy Research Group, this pilot study explores the relationship between leadership styles and empathy (cognitive and affective) levels. This correlational descriptive study involved self-report using 3 instruments. Hogan Empathy Scale (HES) and Emotional Empathy Tendency Scale (EETS) measured cognitive and affective empathy levels. The Multifactoral Leadership Questionnaire (MLQ-5x) was used to determine leadership style. Data analysis yielded evidence of a weak positive correlation between the predominant transformational leadership style and empathy levels in both junior and senior students. This correlation has implications for both nurse educators and future employers.
Neutropenia during HIV Infection: Adverse Consequences and Remedies
Shi, Xin; Sims, Matthew D; Hanna, Michel M; Xie, Ming; Gulick, Peter G; Zheng, Yong-Hui; Basson, Marc D; Zhang, Ping
2016-01-01
Neutropenia frequently occurs in patients with Human immunodeficiency virus (HIV) infection. Causes for neutropenia during HIV infection are multifactoral, including the viral toxicity to hematopoietic tissue, the use of myelotoxic agents for treatment, complication with secondary infections and malignancies, as well as the patient’s association with confounding factors which impair myelopoiesis. An increased prevalence and severity of neutropenia is commonly seen in advanced stages of HIV disease. Decline of neutrophil phagocytic defense in combination with the failure of adaptive immunity renders the host highly susceptible to developing fatal secondary infections. Neutropenia and myelosuppression also restrict the use of many antimicrobial agents for treatment of infections caused by HIV and opportunistic pathogens. In recent years, HIV infection has increasingly become a chronic disease because of progress in antiretroviral therapy (ART). Prevention and treatment of severe neutropenia becomes critical for improving the survival of HIV-infected patients. PMID:24654626
Enzymatic catalysis treatment method of meat industry wastewater using lacasse.
Thirugnanasambandham, K; Sivakumar, V
2015-01-01
The process of meat industry produces in a large amount of wastewater that contains high levels of colour and chemical oxygen demand (COD). So they must be pretreated before their discharge into the ecological system. In this paper, enzymatic catalysis (EC) was adopted to treat the meat wastewater. Box-Behnken design (BBD), an experimental design for response surface methodology (RSM), was used to create a set of 29 experimental runs needed for optimizing of the operating conditions. Quadratic regression models with estimated coefficients were developed to describe the colour and COD removals. The experimental results show that EC could effectively reduce colour (95 %) and COD (86 %) at the optimum conditions of enzyme dose of 110 U/L, incubation time of 100 min, pH of 7 and temperature of 40 °C. RSM could be effectively adopted to optimize the operating multifactors in complex EC process.
Epileptic encephalopathy in children with risk factors for brain damage.
Ricardo-Garcell, Josefina; Harmony, Thalía; Porras-Kattz, Eneida; Colmenero-Batallán, Miguel J; Barrera-Reséndiz, Jesús E; Fernández-Bouzas, Antonio; Cruz-Rivero, Erika
2012-01-01
In the study of 887 new born infants with prenatal and perinatal risk factors for brain damage, 11 children with West syndrome that progressed into Lennox-Gastaut syndrome and another 4 children with Lennox-Gastaut syndrome that had not been preceded by West syndrome were found. In this study we present the main findings of these 15 subjects. In all infants multifactor antecedents were detected. The most frequent risk factors were prematurity and severe asphyxia; however placenta disorders, sepsis, and hyperbilirubinemia were also frequent. In all infants MRI direct or secondary features of periventricular leukomalacia were observed. Followup of all infants showed moderate to severe neurodevelopmental delay as well as cerebral palsy. It is concluded that prenatal and perinatal risk factors for brain damage are very important antecedents that should be taken into account to follow up those infants from an early age in order to detect and treat as early as possible an epileptic encephalopathy.
Study on Data Clustering and Intelligent Decision Algorithm of Indoor Localization
NASA Astrophysics Data System (ADS)
Liu, Zexi
2018-01-01
Indoor positioning technology enables the human beings to have the ability of positional perception in architectural space, and there is a shortage of single network coverage and the problem of location data redundancy. So this article puts forward the indoor positioning data clustering algorithm and intelligent decision-making research, design the basic ideas of multi-source indoor positioning technology, analyzes the fingerprint localization algorithm based on distance measurement, position and orientation of inertial device integration. By optimizing the clustering processing of massive indoor location data, the data normalization pretreatment, multi-dimensional controllable clustering center and multi-factor clustering are realized, and the redundancy of locating data is reduced. In addition, the path is proposed based on neural network inference and decision, design the sparse data input layer, the dynamic feedback hidden layer and output layer, low dimensional results improve the intelligent navigation path planning.
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.
Shaygannejad, Vahid; Janghorbani, Mohsen; Ghorbani, Abbas; Ashtary, Fereshteh; Zakizade, Naser; Nasr, Vida
2006-04-01
Topiramate and sodium valporate are anticonvulsants, demonstrated to be effective as monotherapy for migraine prevention in placebo-controlled trials. To compare the relative efficacy of topiramate and sodium valporate in the prevention of migraine. A 24-week, randomized, double-blind, crossover, clinical trial was conducted from October 2003 to September 2004. A total of 64 patients with migraine headache, aged 14 to 57 years, were randomly allocated to the 2 treatment groups. The first group received topiramate (25 mg daily increment over 1 week to 50 mg) for a total of 2 months. The second group received sodium valporate (200 mg daily increment over 1 week to 400 mg) for 2 months. Response to treatment was assessed at 0, 1, 8, 16, and 24 weeks after start of therapy. Topiramate appeared to be equivalent in efficacy and safety to sodium valporate. A significant decrease in duration, monthly frequency, and intensity of headache occurred in both groups. Of the 32 patients treated with sodium valporate, the mean standard deviation (SD) of monthly migraine frequency decreased from 5.4 (2.5) to 4.0 (2.8) episode per month, headache intensity from 7.7 (1.2) to 5.8 (1.7) by visual analog scale (VAS), and headache duration from 21.3 (14.6) to 12.3 (10.7) hours (P < .001). Correspondingly, in the 32 patients treated with topiramate, the mean SD of monthly headache frequency decreased from 5.4 (2.0) to 3.2 (1.9) per month, headache intensity from 6.9 (1.2) to 3.7 (1.3), and headache duration from 17.3 (8.4) to 3.9 (2.7) hours (P < .001). This study demonstrates that treatment with topiramate and sodium valporate both significantly reduce migraine headache. This effect of topiramate and sodium valporate has previously been shown to reduce migraine headache, and we postulate that treatment with topiramate and sodium valporate may have a similar benefit.
Mostafavi, Seyed-Ali; Mohammadi, Mohammad Reza; Hosseinzadeh, Payam; Eshraghian, Mohammad Reza; Akhondzadeh, Shahin; Hosseinzadeh-Attar, Mohammad Javad; Ranjbar, Elham; Kooshesh, Seyed Mohammad-Ali; Keshavarz, Seyed-Ali
2012-01-01
It is postulated that ritalin may adversely affect sleep, appetite, weight and growth of some children with ADHD. Therefore, we aimed to evaluate melatonin supplementation effects on dietary intake, growth and development of children with ADHD treated with ritalin through circadian cycle modification and appetite mechanisms. After obtaining consent from parents, 50 children aged 7-12 with combined form of AD/HD were randomly divided into two groups based on gender blocks: one received melatonin (3 or 6 mg based on weight) combined with ritalin (1mg/kg) and the other took placebo combined with ritalin (1mg/kg) in a double blind randomized clinical trial. Three-day food record, and standard weight and height of children were evaluated prior to the treatment and 8 weeks after the treatment. Children's appetite and sleep were evaluated in weeks 0, 2, 4 and 8. Hypotheses were then analyzed using SPSS17. Paired sample t-test showed significant changes in sleep latency (23.15±15.25 vs. 17.96±11.66; p=0.047) and total sleep disturbance score (48.84±13.42 vs. 41.30±9.67; p=0.000) before and after melatonin administration, respectively. However, appetite and food intake did not change significantly during the study. Sleep duration and appetite were significantly correlated in melatonin group (Pearson r=0.971, p=0.029). Mean height (138.28±16.24 vs. 141.35±16.78; P=0.000) and weight (36.73±17.82 vs. 38.97±17.93; P=0.005) were significantly increased in melatonin treated children before and after the trial. Administration of melatonin along with ritalin improves height and weight growth of children. These effects may be attributed to circadian cycle modification, increasing sleep duration and the consequent more growth hormone release during sleep.
Moreno-Alcázar, Ana; Radua, Joaquim; Landín-Romero, Ramon; Blanco, Laura; Madre, Mercè; Reinares, Maria; Comes, Mercè; Jiménez, Esther; Crespo, Jose Manuel; Vieta, Eduard; Pérez, Victor; Novo, Patricia; Doñate, Marta; Cortizo, Romina; Valiente-Gómez, Alicia; Lupo, Walter; McKenna, Peter J; Pomarol-Clotet, Edith; Amann, Benedikt L
2017-04-04
Up to 60% of patients with bipolar disorder (BD) have a history of traumatic events, which is associated with greater episode severity, higher risk of comorbidity and higher relapse rates. Trauma-focused treatment strategies for BD are thus necessary but studies are currently scarce. The aim of this study is to examine whether Eye Movement Desensitization and Reprocessing (EMDR) therapy focusing on adherence, insight, de-idealisation of manic symptoms, prodromal symptoms and mood stabilization can reduce episode severity and relapse rates and increase cognitive performance and functioning in patients with BD. This is a single-blind, randomized controlled, multicentre trial in which 82 patients with BD and a history of traumatic events will be recruited and randomly allocated to one of two treatment arms: EMDR therapy or supportive therapy. Patients in both groups will receive 20 psychotherapeutic sessions, 60 min each, during 6 months. The primary outcome is a reduction of affective episodes after 12 and 24 months in favour of the EMDR group. As secondary outcome we postulate a greater reduction in affective symptoms in the EMDR group (as measured by the Bipolar Depression Rating Scale, the Young Mania Rating Scale and the Clinical Global Impression Scale modified for BD), and a better performance in cognitive state, social cognition and functioning (as measured by the Screen for Cognitive Impairment in Psychiatry, The Mayer-Salovey-Caruso Emotional Intelligence Test and the Functioning Assessment Short Test, respectively). Traumatic events will be evaluated by The Holmes-Rahe Life Stress Inventory, the Clinician-administered PTSD Scale and the Impact of Event Scale. The results of this study will provide evidence whether a specific EMDR protocol for patients with BD is effective in reducing affective episodes, affective symptoms and functional, cognitive and trauma symptoms. The trial is registered at ClinicalTrials.gov, identifier: NCT02634372 . Registered on 3 December 2015.
Zhao, Ling; Liu, Jixin; Zhang, Fuwen; Dong, Xilin; Peng, Yulin; Qin, Wei; Wu, Fumei; Li, Ying; Yuan, Kai; von Deneen, Karen M.; Gong, Qiyong; Tang, Zili; Liang, Fanrong
2014-01-01
Background Acupuncture has been commonly used for preventing migraine attacks and relieving pain during a migraine, although there is limited knowledge on the physiological mechanism behind this method. The objectives of this study were to compare the differences in brain activities evoked by active acupoints and inactive acupoints and to investigate the possible correlation between clinical variables and brain responses. Methods and Results A randomized controlled trial and resting-state functional magnetic resonance imaging (fMRI) were conducted. A total of eighty migraineurs without aura were enrolled to receive either active acupoint acupuncture or inactive acupoint acupuncture treatment for 8 weeks, and twenty patients in each group were randomly selected for the fMRI scan at the end of baseline and at the end of treatment. The neuroimaging data indicated that long-term active acupoint therapy elicited a more extensive and remarkable cerebral response compared with acupuncture at inactive acupoints. Most of the regions were involved in the pain matrix, lateral pain system, medial pain system, default mode network, and cognitive components of pain processing. Correlation analysis showed that the decrease in the visual analogue scale (VAS) was significantly related to the increased average Regional homogeneity (ReHo) values in the anterior cingulate cortex in the two groups. Moreover, the decrease in the VAS was associated with increased average ReHo values in the insula which could be detected in the active acupoint group. Conclusions Long-term active acupoint therapy and inactive acupoint therapy have different brain activities. We postulate that acupuncture at the active acupoint might have the potential effect of regulating some disease-affected key regions and the pain circuitry for migraine, and promote establishing psychophysical pain homeostasis. Trial Registration Chinese Clinical Trial Registry ChiCTR-TRC-13003635 PMID:24915066
Unconsummated marriages: a separate and different clinical entity.
Gindin, Leon Roberto; Resnicoff, Diana
2002-01-01
We bring our experience in the treatment of unconsummated marriages (UM). We postulate that it is an independent clinical entity. Since 1991, 199 couples with UM have sought treatment in our center in Buenos Aires. A new approach to this problem is based on an intensive treatment session that lasts a whole day and a pledge to pay only if therapy succeeds. The outcome was a success (97%) with coitus consummation. We make a long-term follow up. The advantages are the brevity of the treatment and lack of desertions. We postulate that UM cannot be approached with an individual perspective or with the usual psychotherapy techniques.
Derk, Chris T; Sandorfi, Nora; Curtis, Mark T
2004-08-01
The pathogenesis of the idiopathic inflammatory myopathies has been postulated to be an environmental trigger causing the expression of the disease in a genetically predisposed patient. We report a case of anti-Jo1 antibody-positive myositis which was associated with pleural effusions, pericardial effusion with tamponade, and 'mechanic's hands', probably related to the consumption of a fermented Kombucha beverage. Kombucha 'mushroom', a symbiosis of yeast and bacteria, is postulated to be the trigger for our patient's disease owing to the proximity of his symptoms to the consumption of the Kombucha beverage.
Upper bound on the efficiency of certain nonimaging concentrators in the physical-optics model
NASA Astrophysics Data System (ADS)
Welford, W. T.; Winston, R.
1982-09-01
Upper bounds on the performance of nonimaging concentrators are obtained within the framework of scalar-wave theory by using a simple approach to avoid complex calculations on multiple phase fronts. The approach consists in treating a theoretically perfect image-forming device and postulating that no non-image-forming concentrator can have a better performance than such an ideal image-forming system. The performance of such a system can be calculated according to wave theory, and this will provide, in accordance with the postulate, upper bounds on the performance of nonimaging systems. The method is demonstrated for a two-dimensional compound parabolic concentrator.
NASA Technical Reports Server (NTRS)
Foote, M.; Hunter, J. P.; Janis, C. M.; Sepkoski, J. J. Jr
1999-01-01
Some molecular clock estimates of divergence times of taxonomic groups undergoing evolutionary radiation are much older than the groups' first observed fossil record. Mathematical models of branching evolution are used to estimate the maximal rate of fossil preservation consistent with a postulated missing history, given the sum of species durations implied by early origins under a range of species origination and extinction rates. The plausibility of postulated divergence times depends on origination, extinction, and preservation rates estimated from the fossil record. For eutherian mammals, this approach suggests that it is unlikely that many modern orders arose much earlier than their oldest fossil records.
Hypotheses on the appearance of life on Earth (review).
Dose, K
1986-01-01
It is generally accepted within the natural sciences that life emerged on Earth by a kind of proto-Darwinian evolution from molecular assemblies that were predominantly formed from the various constituents of the primitive atmosphere and hydrosphere. Evolutionary stages under discussion are: the self-organization of spontaneously formed biomolecules into early precursors of life (protobionts), their stepwise evolution via (postulated) protocells to (postulated) progenotes and the Darwinian evolution from progenotes to the three kingdoms of contemporary organisms (archaebacteria, eubacteria and eukaryotes). Considerable discrepancies between scientists have arisen because all evolutionary stages from prebiotic molecules to progenotes are entirely hypothetical and so are the postulated environmental conditions. We can only theorize that all those environmental conditions that allow the existence of the various forms of contemporary life might have allowed also the development of their precursors. Because of all these difficulties the hypothesis that life came to our planet from a remote place of our universe (panspermia) has been revived. But experimental evidence only supports the view that spores can--under favorable circumstances--survive a relatively short journey within our solar system (interplanetary transfer of life). It is extremely unlikely that spores can survive a journey of hundreds or thousands of years through interstellar space.
Radiation and matter: Electrodynamics postulates and Lorenz gauge
NASA Astrophysics Data System (ADS)
Bobrov, V. B.; Trigger, S. A.; van Heijst, G. J.; Schram, P. P.
2016-11-01
In general terms, we have considered matter as the system of charged particles and quantized electromagnetic field. For consistent description of the thermodynamic properties of matter, especially in an extreme state, the problem of quantization of the longitudinal and scalar potentials should be solved. In this connection, we pay attention that the traditional postulates of electrodynamics, which claim that only electric and magnetic fields are observable, is resolved by denial of the statement about validity of the Maxwell equations for microscopic fields. The Maxwell equations, as the generalization of experimental data, are valid only for averaged values. We show that microscopic electrodynamics may be based on postulation of the d'Alembert equations for four-vector of the electromagnetic field potential. The Lorenz gauge is valid for the averages potentials (and provides the implementation of the Maxwell equations for averages). The suggested concept overcomes difficulties under the electromagnetic field quantization procedure being in accordance with the results of quantum electrodynamics. As a result, longitudinal and scalar photons become real rather than virtual and may be observed in principle. The longitudinal and scalar photons provide not only the Coulomb interaction of charged particles, but also allow the electrical Aharonov-Bohm effect.
Neutronic analysis of the 1D and 1E banks reflux detection system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blanchard, A.
1999-12-21
Two H Canyon neutron monitoring systems for early detection of postulated abnormal reflux conditions in the Second Uranium Cycle 1E and 1D Mixer-Settle Banks have been designed and built. Monte Carlo neutron transport simulations using the general purpose, general geometry, n-particle MCNP code have been performed to model expected response of the monitoring systems to varying conditions.The confirmatory studies documented herein conclude that the 1E and 1D neutron monitoring systems are able to achieve adequate neutron count rates for various neutron source and detector configurations, thereby eliminating excessive integration count time. Neutron count rate sensitivity studies are also performed. Conversely,more » the transport studies concluded that the neutron count rates are statistically insensitive to nitric acid content in the aqueous region and to the transition region length. These studies conclude that the 1E and 1D neutron monitoring systems are able to predict the postulated reflux conditions for all examined perturbations in the neutron source and detector configurations. In the cases examined, the relative change in the neutron count rates due to postulated transitions from normal {sup 235}U concentration levels to reflux levels remain satisfactory detectable.« less
Integrated information theory of consciousness: an updated account.
Tononi, G
2012-01-01
This article presents an updated account of integrated information theory of consciousness (IIT) and some of its implications. IIT stems from thought experiments that lead to phenomenological axioms and ontological postulates. The information axiom asserts that every experience is one out of many, i.e. specific - it is what it is by differing in its particular way from a large repertoire of alternatives. The integration axiom asserts that each experience is one, i.e. unified - it cannot be reduced to independent components. The exclusion axiom asserts that every experience is definite - it is limited to particular things and not others and flows at a particular speed and resolution. IIT formalizes these intuitions with three postulates. The information postulate states that only "differences that make a difference" from the intrinsic perspective of a system matter: a mechanism generates cause-effect information if its present state has specific past causes and specific future effects within a system. The integration postulate states that only information that is irreducible matters: mechanisms generate integrated information only to the extent that the information they generate cannot be partitioned into that generated within independent components. The exclusion postulate states that only maxima of integrated information matter: a mechanism specifies only one maximally irreducible set of past causes and future effects - a concept. A complex is a set of elements specifying a maximally irreducible constellation of concepts, where the maximum is evaluated at the optimal spatio-temporal scale. Its concepts specify a maximally integrated conceptual information structure or quale, which is identical with an experience. Finally, changes in information integration upon exposure to the environment reflect a system's ability to match the causal structure of the world. After introducing an updated definition of information integration and related quantities, the article presents some theoretical considerations about the relationship between information and causation and about the relational structure of concepts within a quale. It also explores the relationship between the temporal grain size of information integration and the dynamic of metastable states in the corticothalamic complex. Finally, it summarizes how IIT accounts for empirical findings about the neural substrate of consciousness, and how various aspects of phenomenology may in principle be addressed in terms of the geometry of information integration.
Integrated information theory of consciousness: an updated account.
Tononi, G
2012-12-01
This article presents an updated account of integrated information theory of consciousness (liT) and some of its implications. /IT stems from thought experiments that lead to phenomenological axioms (existence, compositionality, information, integration, exclusion) and corresponding ontological postulates. The information axiom asserts that every experience is spec~fic - it is what it is by differing in its particular way from a large repertoire of alternatives. The integration axiom asserts that each experience is unified- it cannot be reduced to independent components. The exclusion axiom asserts that every experience is definite - it is limited to particular things and not others and flows at a particular speed and resolution. /IT formalizes these intuitions with postulates. The information postulate states that only "differences that make a difference" from the intrinsic perpective of a system matter: a mechanism generates cause-effect information if its present state has selective past causes and selective future effects within a system. The integration postulate states that only information that is irreducible matters: mechanisms generate integrated information only to the extent that the information they generate cannot be partitioned into that generated within independent components. The exclusion postulate states that only maxima of integrated information matter: a mechanism specifies only one maximally irreducible set of past causes and future effects - a concept. A complex is a set of elements specifying a maximally irreducible constellation of concepts, where the maximum is evaluated over elements and at the optimal spatiatemporal scale. Its concepts specify a maximally integrated conceptual information structure or quale, which is identical with an experience. Finally, changes in information integration upon exposure to the environment reflect a system's ability to match the causal structure of the world. After introducing an updated definition of information integration and related quantities, the article presents some theoretical considerations about the relationship between information and causation and about the relational structure of concepts within a qua/e. It also explores the relationship between the temporal grain size of information integration and the dynamic of metastable states in the corticothalamic complex. Finally, it summarizes how liT accounts for empirical findings about the neural substrate of consciousness, and how various aspects of phenomenology may in principle be addressed in terms of the geometry of information integration.
Logroscino, Giancarlo; Capozzo, Rosa; Tortelli, Rosanna; Marin, Benoît
2016-01-01
The investigator is faced with several challenges when planning a randomized clinical trial (RCT). In the early phase, issues are particularly challenging for RCTs in neurodegenerative disorders (NDD). At the time of inclusion in the study, an early and accurate diagnosis is mandatory. Variability of diagnostic criteria, mostly based on clinical grounds, lag time between onset and enrolment, and phenotypic heterogeneity are the main drivers of diagnostic complexity. High-quality data in terms of diagnostic reliability, phenotypic description, follow-up, and evaluation of outcomes are key determinants and are highly conditioned by the expertise of the investigators and center recruitment rate. Representativeness of NDD patients is mandatory to postulate the generalizability of the results of RCTs. There is, however, a systematic selection bias in terms of age (more likely to be younger), sex (more likely to be male), ethnicity (more likely to be of European/Caucasian origin), and other prognostic factors (more likely to be favorable). In the publication phase, researchers need to report properly all of the main features of the RCT. Consolidated Standards of Reporting Trials (CONSORT) facilitates the report and interpretation of RCTs, but adherence to these guidelines needs to be improved. Several issues discussed in this review may alter the internal and external validity of an RCT. To date, the impact on phenotype at study entry has often been overlooked. A differential effect of the selection of subjects and of specific clinical and nonclinical features needs to be systematically explored in the RCT planning phase. © 2016 S. Karger AG, Basel.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bekelman, Justin E.; Yahalom, Joachim
2009-02-01
Purpose: Standards for the reporting of radiotherapy details in randomized controlled trials (RCTs) are lacking. Although radiotherapy (RT) is an important component of curative therapy for Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), we postulated that RT reporting may be inadequate in Phase III HL and NHL trials. Methods and Materials: We searched PubMed and the Cochrane registry for reports of RCTs involving RT and either HL or NHL published between 1998 and 2007. We screened 133 titles and abstracts to identify relevant studies. We included a total of 61 reports. We assessed these reports for the presence of sixmore » quality measures: target volume, radiation dose, fractionation, radiation prescription, quality assurance (QA) process use, and adherence to QA (i.e., reporting of major or minor deviations). Results: Of 61 reports, 23 (38%) described the target volume. Of the 42 reports involving involved-field RT alone, only 8 (19%) adequately described the target volume. The radiation dose and fractionation was described in most reports (54 reports [89%] and 39 reports [64%], respectively). Thirteen reports specified the RT prescription point (21%). Only 12 reports (20%) described using a RT QA process, and 7 reports (11%) described adherence to the QA process. Conclusion: Reporting of RT in HL and NHL RCTs is deficient. Because the interpretation, replication, and application of RCT results depend on adequate description and QA of therapeutic interventions, consensus standards for RT reporting should be developed and integrated into the peer-review process.« less
Meneses-Echávez, José Francisco; Jiménez, Emilio González; Río-Valle, Jacqueline Schmidt; Correa-Bautista, Jorge Enrique; Izquierdo, Mikel; Ramírez-Vélez, Robinson
2016-08-25
Insulin-like growth factors (IGF´s) play a crucial role in controlling cancer cell proliferation, differentiation and apoptosis. Exercise has been postulated as an effective intervention in improving cancer-related outcomes and survival, although its effects on IGF´s are not well understood. This meta-analysis aimed to determine the effects of exercise in modulating IGF´s system in breast cancer survivors. Databases of PuMed, EMBASE, Cochrane Central Register of Controlled Trials, EMBASE, ClinicalTrials.gov, SPORTDiscus, LILACS and Scopus were systematically searched up to November 2014. Effect estimates were calculated through a random-effects model of meta-analysis according to the DerSimonian and Laird method. Heterogeneity was evaluated with the I (2) test. Risk of bias and methodological quality were evaluated using the PEDro score. Five randomized controlled trials (n = 235) were included. Most women were post-menopausal. High-quality and low risk of bias were found (mean PEDro score = 6.2 ± 1). Exercise resulted in significant improvements on IGF-I, IGF-II, IGFBP-I, IGFBP-3, Insulin and Insulin resistance (P < 0.05). Non-significant differences were found for Glucose. Aerobic exercise improved IGF-I, IGFBP-3 and Insulin. No evidence of publication bias was detected by Egger´s test (p = 0.12). Exercise improved IGF´s in breast cancer survivors. These findings provide novel insight regarding the molecular effects of exercise on tumoral microenvironment, apoptosis and survival in breast cancer survivors.
Wyatt, Kirk D; Branda, Megan E; Inselman, Jonathan W; Ting, Henry H; Hess, Erik P; Montori, Victor M; LeBlanc, Annie
2014-09-02
Gender differences in communication styles between clinicians and patients have been postulated to impact patient care, but the extent to which the gender dyad structure impacts outcomes in shared decision making remains unclear. Participant-level meta-analysis of 775 clinical encounters within 7 randomized trials where decision aids, shared decision making tools, were used at the point of care. Outcomes analysed include decisional conflict scale scores, satisfaction with the clinical encounter, concordance between stated decision and action taken, and degree of patient engagement by the clinician using the OPTION scale. An estimated minimal important difference was used to determine if nonsignificant results could be explained by low power. We did not find a statistically significant interaction between clinician/patient gender mix and arm for decisional conflict, satisfaction with the clinical encounter or patient engagement. A borderline significant interaction (p = 0.05) was observed for one outcome: concordance between stated decision and action taken, where encounters with female clinician/male patient showed increased concordance in the decision aid arm compared to control (8% more concordant encounters). All other gender dyads showed decreased concordance with decision aid use (6% fewer concordant encounters for same-gender, 16% fewer concordant encounters for male clinician/female patient). In this participant-level meta-analysis of 7 randomized trials, decision aids used at the point of care demonstrated comparable efficacy across gender dyads. Purported barriers to shared decision making based on gender were not detected when tested for a minimum detected difference. ClinicalTrials.gov NCT00888537, NCT01077037, NCT01029288, NCT00388050, NCT00578981, NCT00949611, NCT00217061.
Azhar, Zain M; Zubaidah, Jamil O; Norjan, Khin O N; Zhuang, Candy Yi-Jing; Tsang, Fai
2013-08-15
It has long been postulated that the relative abundance of specific nutrients can affect cognitive processes and emotions. Newly described influences of dietary factors on neuronal function and synaptic plasticity have revealed some of the vital mechanisms that could be responsible for the action of diet on brain health and cognitive function. Here, through a double-blind, randomized, placebo-controlled trial, we asked if the newly discovered chicken meat ingredient-168 (CMI-168) could be beneficial to the cognitive function in healthy adults. Normal, healthy subjects were supplemented with either placebo or CMI-168 for 6 weeks. The subjects were given a series of cognitive tests to examine their levels of cognitive functioning at the beginning and end of supplementation, as well as two weeks after termination of supplementation. The combination of these tests, namely Digit Span Backwards, Letter-Number Sequencing, and the Rey Auditory Verbal Learning Test (RAVLT), was used to assess the subjects' attention and working memory. For all comparisons, the probability level of p < 0.05 was taken as statistically significant using repeated measure 2-way ANOVA followed by Bonferroni post-hoc test. Overall, subjects supplemented with CMI-168 showed significantly (p < 0.01) better performance in all cognitive tests after 6 weeks' supplementation compared to control and such superior performance was maintained even 2 weeks after termination of supplementation. The present study reveals the cognition-enhancing properties of a recently developed chicken meat ingredient, likely arising from the promotion of attention and prefrontal cortex functions.
Chetty, R; Hafezi, S; Montgomery, E
2009-05-01
Enterocolic lymphocytic phlebitis (ELP) is an uncommon cause of bowel pathology and most frequently results in ischaemia. It is characterised by an artery-sparing, venulocentric lymphoid infiltrate that causes a phlebitis and vascular compromise. Rare cases of ELP have been encountered with lymphocytic colitis in the absence of ischaemic bowel change. The present study examined the occurrence of ELP in the setting of diversion colitis and inflammatory bowel disease, as well as in random colectomy specimens. The study cohort comprised the following: 26 completion proctectomy specimens for ulcerative colitis with superimposed diversion colitis in the rectal stump; 3 colectomy specimens for Crohn disease with diversion colitis; 6 colectomy specimens for adenocarcinoma and/or diverticular disease with diversion colitis; 34 resection specimens with ulcerative colitis only; 19 with Crohn disease only; and 100 random colon resection specimens for adenocarcinoma, adenoma, diverticular disease and ischaemia. ELP was present in 18 of the 26 ulcerative colitis cases with diversion colitis, 3/3 Crohn disease cases with diversion colitis, 1/6 cases of diverticular disease with diversion colitis, 6/34 cases of ulcerative colitis without diversion, 2/19 Crohn disease cases without diversion colitis, and only 1 of 100 colectomy cases without inflammatory bowel disease or diversion colitis. ELP occurs most frequently in cases that have been diverted for inflammatory bowel disease. Fewer cases of ELP were noted in cases of inflammatory bowel disease in the absence of diversion colitis. It is postulated that altered bowel flora and immune dysregulation may be pivotal in the causation of this association.
Mechanism for generation of left isomerism in Ccdc40 mutant embryos
Sugrue, Kelsey F.
2017-01-01
Leftward fluid flow in the mouse node is generated by cilia and is critical for initiating asymmetry of the left-right axis. Coiled-coil domain containing-40 (Ccdc40) plays an evolutionarily conserved role in the assembly of motile cilia and establishment of the left-right axis. Approximately one-third of Ccdc40lnks mutant embryos display situs defects and here we investigate the underlying mechanism. Ccdc40lnks mutants show delayed induction of markers of the left-lateral plate mesoderm (L-LPM) including Lefty1, Lefty2 and Nodal. Consistent with defective cilia motility compromising fluid flow across the node, initiation of asymmetric perinodal Cerberus like-2 (Cerl2) expression is delayed and then randomized. This is followed by delayed and then randomized asymmetric Nodal expression around the node. We propose a model to explain how left isomerism arises in a proportion of Ccdc40lnks mutants. We postulate that with defective motile cilia, Cerl2 expression remains symmetric and Nodal is antagonized equally on both sides of the node. This effectively reduces Nodal activation bilaterally, leading to reduced and delayed activation of Nodal and its antagonists in the LPM. This model is further supported by the failure to establish Nodal expression in the left-LPM with reduced Nodal gene dosage in Ccdc40lnks/lnks;NodalLacZ/+ mutants causing a predominance of right not left isomerism. Together these results suggest a model where cilia generated fluid flow in the node functions to ensure robust Nodal activation and a timely left-sided developmental program in the LPM. PMID:28182636
Self-consistent asset pricing models
NASA Astrophysics Data System (ADS)
Malevergne, Y.; Sornette, D.
2007-08-01
We discuss the foundations of factor or regression models in the light of the self-consistency condition that the market portfolio (and more generally the risk factors) is (are) constituted of the assets whose returns it is (they are) supposed to explain. As already reported in several articles, self-consistency implies correlations between the return disturbances. As a consequence, the alphas and betas of the factor model are unobservable. Self-consistency leads to renormalized betas with zero effective alphas, which are observable with standard OLS regressions. When the conditions derived from internal consistency are not met, the model is necessarily incomplete, which means that some sources of risk cannot be replicated (or hedged) by a portfolio of stocks traded on the market, even for infinite economies. Analytical derivations and numerical simulations show that, for arbitrary choices of the proxy which are different from the true market portfolio, a modified linear regression holds with a non-zero value αi at the origin between an asset i's return and the proxy's return. Self-consistency also introduces “orthogonality” and “normality” conditions linking the betas, alphas (as well as the residuals) and the weights of the proxy portfolio. Two diagnostics based on these orthogonality and normality conditions are implemented on a basket of 323 assets which have been components of the S&P500 in the period from January 1990 to February 2005. These two diagnostics show interesting departures from dynamical self-consistency starting about 2 years before the end of the Internet bubble. Assuming that the CAPM holds with the self-consistency condition, the OLS method automatically obeys the resulting orthogonality and normality conditions and therefore provides a simple way to self-consistently assess the parameters of the model by using proxy portfolios made only of the assets which are used in the CAPM regressions. Finally, the factor decomposition with the self-consistency condition derives a risk-factor decomposition in the multi-factor case which is identical to the principal component analysis (PCA), thus providing a direct link between model-driven and data-driven constructions of risk factors. This correspondence shows that PCA will therefore suffer from the same limitations as the CAPM and its multi-factor generalization, namely lack of out-of-sample explanatory power and predictability. In the multi-period context, the self-consistency conditions force the betas to be time-dependent with specific constraints.
Ryan, Michael G
2013-11-01
Nutrient supply often limits growth in forest ecosystems and may limit the response of growth to an increase in other resources, or to more favorable environmental factors such as temperature and soil water. To explore the consequences and mechanisms of optimum nutrient supply for forest growth, the Flakaliden research site was established in 1986 on a young Norway spruce site with nutrient-poor soil. This special section on research at Flakaliden presents five papers that explore different facets of nutrition, atmospheric CO2 concentration, [CO2], and increased temperature treatments, using the original experiment as a base. Research at Flakaliden shows the dominant role of nutrition in controlling the response of growth to the increased photosynthesis promoted by elevated [CO2] and temperature. Experiments with whole-tree chambers showed that all treatments (air temperature warming, elevated [CO2] and optimum nutrition) increased shoot photosynthesis by 30-50%, but growth only increased with [CO2] when combined with the optimum nutrition treatment. Elevated [CO2] and temperature increased shoot photosynthesis by increasing the slope between light-saturated photosynthesis and foliar nitrogen by 122%, the initial slope of the light response curve by 52% and apparent quantum yield by 10%. Optimum nutrition also decreased photosynthetic capacity by 17%, but increased it by 62% in elevated [CO2], as estimated from wood δ(13)C. Elevated air temperature advanced spring recovery of photosynthesis by 37%, but spring frost events remained the controlling factor for photosynthetic recovery, and elevated [CO2] did not affect this. Increased nutrient availability increased wood growth primarily through a 50% increase in tracheid formation, mostly during the peak growth season. Other notable contributions of research at Flakaliden include exploring the role of optimal nutrition in large-scale field trials with foliar analysis, using an ecosystem approach for multifactor experiments, development of whole-tree chambers allowing inexpensive environmental manipulations, long-term deployment of shoot chambers for continuous measurements of gas exchange and exploring the ecosystem response to soil and aboveground tree warming. The enduring legacy of Flakaliden will be the rich data set of long-term, multifactor experiments that has been and will continue to be used in many modeling and cross-site comparison studies.
Multivariate generalized multifactor dimensionality reduction to detect gene-gene interactions
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
Tolerance of an Antarctic Bacterium to Multiple Environmental Stressors.
Sengupta, Dipanwita; Sangu, Kavya; Shivaji, Sisinthy; Chattopadhyay, Madhab K
2015-10-01
A population of cold-tolerant Antarctic bacteria was screened for their ability to tolerate other environmental stress factors. Besides low temperature, they were predominantly found to be tolerant to alkali. Attempt was also made to postulate a genetic basis of their multistress-tolerance. Transposon mutagenesis of an isolate Pseudomonas syringae Lz4W was performed, and mutants with delayed growth at low temperature were further screened for sensitivity to some other stress factors. A number of multistress-sensitive mutants were isolated. The mutated gene in one of the mutants sensitive to low temperature, acid and alkali was found to encode citrate synthase. Possible role of citrate synthase in conferring multistress-tolerance was postulated.
2009-07-01
auteurs discu- tent des implications des resultats pour les theories qui postulent un effet de I’emotion sur la perception du risque et pour com...effect of global negative emotion on perceived threat . The authors discuss implications of the findings for theories that postulate an effect of... auteurs ont mene une etude perception j emotion j experimentale afin d’examiner les effets d’etats emotionnels Specifi- ques (peur et colere) et globaux
On a Quantum Model of Brain Activities
NASA Astrophysics Data System (ADS)
Fichtner, K.-H.; Fichtner, L.; Freudenberg, W.; Ohya, M.
2010-01-01
One of the main activities of the brain is the recognition of signals. A first attempt to explain the process of recognition in terms of quantum statistics was given in [6]. Subsequently, details of the mathematical model were presented in a (still incomplete) series of papers (cf. [7, 2, 5, 10]). In the present note we want to give a general view of the principal ideas of this approach. We will introduce the basic spaces and justify the choice of spaces and operations. Further, we bring the model face to face with basic postulates any statistical model of the recognition process should fulfill. These postulates are in accordance with the opinion widely accepted in psychology and neurology.
Retrieval of Missing Spliced Leader in Dinoflagellates
Zhang, Huan; Lin, Senjie
2009-01-01
Spliced leader (SL) trans-splicing has recently been shown to be a common mRNA processing mechanism in dinoflagellates, in which a short (22-nt) sequence, DCCGUAGCCAUUUUGGCUCAAG (D = U, A, or G), is transplanted from the 5′-end of a small non-coding RNA (SL RNA) to the 5′ end of mRNA molecules. The widespread existence of the mechanism in dinoflagellates has been demonstrated by detection of this SL (DinoSL) in a wide phylogenetic range of dinoflagellates. Furthermore, the presence of DinoSL in the transcripts of highly diverse groups of nuclear-encoded genes has led us to postulate that SL trans-splicing is universal in dinoflagellate nuclear genome. However, some observations inconsistent to this postulation have been reported, exemplified by a recent article reporting apparent absence of DinoSL in the transcripts of some nuclear-encoded genes in Amphidinium carterae. Absence of SL in these gene transcripts would have important implication on gene regulation in dinoflagellates and utility of DinoSL as a universal dinoflagellate-specific primer to study dinoflagellate transcriptomics. In this study, we re-examined transcripts of these genes and found that all of them actually contained DinoSL. Therefore, results to date are consistent to our initial postulation that DinoSL occurs in all dinoflagellate nuclear-encoded mRNAs. PMID:19122814
One-dimensional Numerical Model of Transient Discharges in Air of a Spatial Plasma Ignition Device
NASA Astrophysics Data System (ADS)
Saceleanu, Florin N.
This thesis examines the modes of discharge of a plasma ignition device. Oscilloscope data of the discharge voltage and current are analyzed for various pressures in air at ambient temperature. It is determined that the discharge operates in 2 modes: a glow discharge and a postulated streamer discharge. Subsequently, a 1-dimensional fluid simulation of plasma using the finite volume method (FVM) is developed to gain insight into the particle kinetics. Transient results of the simulation agree with theories of electric discharges; however, quasi-steady state results were not reached due to high diffusion time of ions in air. Next, an ordinary differential equation (ODE) is derived to understand the discharge transition. Simulated results were used to estimate the voltage waveform, which describes the ODE's forcing function; additional simulated results were used to estimate the discharge current and the ODE's non-linearity. It is found that the ODE's non-linearity increases exponentially for capacitive discharges. It is postulated that the non-linearity defines the mode transition observed experimentally. The research is motivated by Spatial Plasma Discharge Ignition (SPDI), an innovative ignition system postulated to increase combustion efficiency in automobile engines for up to 9%. The research thus far can only hypothesize SPDI's benefits on combustion, based on the literature review and the modes of discharge.
The IAT shows no evidence for Kandinsky's color-shape associations.
Makin, Alexis D J; Wuerger, Sophie M
2013-01-01
In the early twentieth century, the Bauhaus revolutionized art and design by using simple colors and forms. Wassily Kandinsky was especially interested in the relationship of these two visual attributes and postulated a fundamental correspondence between color and form: yellow triangle, red square and blue circle. Subsequent empirical studies used preference judgments to test Kandinsky's original color-form combinations, usually yielding inconsistent results. We have set out to test the validity of these postulated associations by using the Implicit Association Test. Participants pressed one of two buttons on each trial. On some trials they classified shapes (e.g., circle or triangle). On interleaved trials they classified colors (e.g., blue or yellow). Response times should theoretically be faster when the button mapping follows Kandinsky's associations: For example, when the left key is used to report blue or circle and the right is used for yellow and triangle, than when the response mapping is the opposite of this (blue or triangle, yellow or circle). Our findings suggest that there is no implicit association between the original color-form combinations. Of the three combinations we tested, there was only a marginal effect in one case. It can be concluded that the IAT does not support Kandinsky's postulated color-form associations, and that these are probably not a universal property of the visual system.
Evolutionary theory and teleology.
O'Grady, R T
1984-04-21
The order within and among living systems can be explained rationally by postulating a process of descent with modification, effected by factors which are extrinsic or intrinsic to the organisms. Because at the time Darwin proposed his theory of evolution there was no concept of intrinsic factors which could evolve, he postulated a process of extrinsic effects--natural selection. Biological order was thus seen as an imposed, rather than an emergent, property. Evolutionary change was seen as being determined by the functional efficiency (adaptedness) of the organism in its environment, rather than by spontaneous changes in intrinsically generated organizing factors. The initial incompleteness of Darwin's explanatory model, and the axiomatization of its postulates in neo-Darwinism, has resulted in a theory of functionalism, rather than structuralism. As such, it introduces an unnecessary teleology which confounds evolutionary studies and reduces the usefulness of the theory. This problem cannot be detected from within the neo-Darwinian paradigm because the different levels of end-directed activity--teleomatic, teleonomic, and teleological--are not recognized. They are, in fact, considered to influence one another. The theory of nonequilibrium evolution avoids these problems by returning to the basic principles of biological order and developing a structuralist explanation of intrinsically generated change. Extrinsic factors may affect the resultant evolutionary pattern, but they are neither necessary nor sufficient for evolution to occur.
NASA Astrophysics Data System (ADS)
Prince, N. H. E.
2005-10-01
Meaning and purpose can be given to life, consciousness, the laws of physics, etc. If one assumes that the Universe is endowed with some form of (strong) anthropic principle. In particular, the final anthropic principle (FAP) of Barrow and Tipler postulates that intelligent life will continue in the Universe until the far future when the computational power of descendent civilizations will be sufficient to run simulations of enormous scale and power. Tipler has claimed that it will be possible to create simulations with rendered environments and inhabitants, i.e. intelligent software constructs, which are effectively ‘people’. Proponents of this FAP claim that if both substrate independence and the pattern identity postulate hold, then these simulations would be able to contain reanimated individuals that once lived. These claims have been heavily criticized but the growing study of physical eschatology, initiated by Freeman Dyson in a seminal work, and the developments in computational theory have made some progress in showing that simulations containing intelligent information processing software constructs, which may be conscious, are not only feasible but may be a reality within the next few centuries. In this work, arguments and conservative calculations are given which concur with these latter more minimal claims. FAP-type simulations inevitably rely on cosmology type, but current observations would seem to rule appropriate models out. However, it is argued that dark energy, described in the recent forms of ‘quintessence’ cosmological models may show the current conclusions from observations to be too presumptive. In this paper some relevant physical and cosmological aspects are reviewed in the light of the recent propositions regarding the plausibility of certain simulations given by Bostrom, and the longer held postulate of finite nature due to Fredkin which has grown in credibility, following advances in quantum mechanics and the computational theory of cellular automata. This latter postulate supports the conclusions of Bostrom, which, under certain plausible assumptions, can imply that our Universe is itself already a simulated entity. It is demonstrated in this paper how atemporal memory connections could make efficient ancestor simulations possible, solving many of the objections faced by the FAP of Barrow and Tipler. Also, if finite nature is true then it can offer a similar vindication to this FAP. Indeed the conclusions of this postulate can be realized more easily, but only if the existence of life within the simulation/Universe is not merely incidental to the (currently unknown) purpose for which it was generated to fulfil.
Chromosome rearrangements and the evolution of genome structuring and adaptability.
Crombach, Anton; Hogeweg, Paulien
2007-05-01
Eukaryotes appear to evolve by micro and macro rearrangements. This is observed not only for long-term evolutionary adaptation, but also in short-term experimental evolution of yeast, Saccharomyces cerevisiae. Moreover, based on these and other experiments it has been postulated that repeat elements, retroposons for example, mediate such events. We study an evolutionary model in which genomes with retroposons and a breaking/repair mechanism are subjected to a changing environment. We show that retroposon-mediated rearrangements can be a beneficial mutational operator for short-term adaptations to a new environment. But simply having the ability of rearranging chromosomes does not imply an advantage over genomes in which only single-gene insertions and deletions occur. Instead, a structuring of the genome is needed: genes that need to be amplified (or deleted) in a new environment have to cluster. We show that genomes hosting retroposons, starting with a random order of genes, will in the long run become organized, which enables (fast) rearrangement-based adaptations to the environment. In other words, our model provides a "proof of principle" that genomes can structure themselves in order to increase the beneficial effect of chromosome rearrangements.
Prenatal meditation influences infant behaviors.
Chan, Ka Po
2014-11-01
Meditation is important in facilitating health. Pregnancy health has been shown to have significant consequences for infant behaviors. In view of limited studies on meditation and infant temperament, this study aims to explore the effects of prenatal meditation on these aspects. The conceptual framework was based on the postulation of positive relationships between prenatal meditation and infant health. A randomized control quantitative study was carried out at Obstetric Unit, Queen Elizabeth Hospital in Hong Kong. 64 pregnant Chinese women were recruited for intervention and 59 were for control. Outcome measures were cord blood cortisol, infant salivary cortisol, and Carey Infant Temperament Questionnaire. Cord blood cortisol level of babies was higher in the intervention group (p<0.01) indicates positive health status of the newborns verifies that prenatal meditation can influence fetal health. Carey Infant Temperament Questionnaire showed that the infants of intervention group have better temperament (p<0.05) at fifth month reflects the importance of prenatal meditation in relation to child health. Present study concludes the positive effects of prenatal meditation on infant behaviors and recommends that pregnancy care providers should provide prenatal meditation to pregnant women. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Chen, Ang; Liu, Xinlan
2008-03-01
The expectancy-value theory postulates that motivation relies on individuals' beliefs of success, perceived Attainment, Intrinsic Interest, and Utility values and Cost. This study examined Chinese college students' expectancy-value motivation in relation to physical education and self-initiated physical activity. A random sample of 368 Chinese university students responded to questionnaires on perceived expectancy beliefs, perceived values, and cost in terms of their experiences in mandatory physical education programs and in self-initiated after-school physical activity. They reported their choice decisions for continuing physical education. Data were analyzed using descriptive statistics, X2, logistic and linear regressions. The physical education curriculum was perceived as a major cost to motivation. Motivated by the Intrinsic Interest and Utility value, most students chose to continue to take physical education. Self-initiated after-school physical activity was motivated by the Attainment value only. No association was found between self-initiated physical activity and Liking or Disliking of physical education. Motivation for physical education and for self-initiated physical activity derived from different perceived values. The Attainment value motivates the students for self-initiated physical activity, whereas Intrinsic Interest and Utility values motivate them to choose to continue physical education.
On the possible origin and evolution of the genetic code
NASA Technical Reports Server (NTRS)
Jukes, T. H.
1974-01-01
The genetic code is examined for indications of possible preceding codes that existed during early evolution. Eight of the 20 amino acids are coded by 'quartets' of codons with fourfold degeneracy, and 16 such quartets can exist, so that an earlier code could have provided for 15 or 16 amino acids, rather than 20. If twofold degeneracy is postulated for the first position of the codon, there could have been ten amino acids in the code. It is speculated that these may have been phenylalanine, valine, proline, alanine, histidine, glutamine, glutanic acid, aspartic acid, cysteine and glycine. There is a notable deficiency of arginine in proteins, despite the fact that it has six codons. Simultaneously, there is more lysine in proteins than would be expected from its two codons, if the four bases in mRNA are equiprobable and are arranged randomly. It is speculated that arginine is an 'intruder' into the genetic code, and that it may have displayed another amino acid such as ornithine, or may even have displayed lysine from some of its previous codon assignments. As a result, natural selection has favored lysine against the fact that it has only two codons.
River meanders - Theory of minimum variance
Langbein, Walter Basil; Leopold, Luna Bergere
1966-01-01
Meanders are the result of erosion-deposition processes tending toward the most stable form in which the variability of certain essential properties is minimized. This minimization involves the adjustment of the planimetric geometry and the hydraulic factors of depth, velocity, and local slope.The planimetric geometry of a meander is that of a random walk whose most frequent form minimizes the sum of the squares of the changes in direction in each successive unit length. The direction angles are then sine functions of channel distance. This yields a meander shape typically present in meandering rivers and has the characteristic that the ratio of meander length to average radius of curvature in the bend is 4.7.Depth, velocity, and slope are shown by field observations to be adjusted so as to decrease the variance of shear and the friction factor in a meander curve over that in an otherwise comparable straight reach of the same riverSince theory and observation indicate meanders achieve the minimum variance postulated, it follows that for channels in which alternating pools and riffles occur, meandering is the most probable form of channel geometry and thus is more stable geometry than a straight or nonmeandering alinement.
Direct observation of nanowire growth and decomposition.
Rackauskas, Simas; Shandakov, Sergey D; Jiang, Hua; Wagner, Jakob B; Nasibulin, Albert G
2017-09-26
Fundamental concepts of the crystal formation suggest that the growth and decomposition are determined by simultaneous embedding and removal of the atoms. Apparently, by changing the crystal formation conditions one can switch the regimes from the growth to decomposition. To the best of our knowledge, so far this has been only postulated, but never observed at the atomic level. By means of in situ environmental transmission electron microscopy we monitored and examined the atomic layer transformation at the conditions of the crystal growth and its decomposition using CuO nanowires selected as a model object. The atomic layer growth/decomposition was studied by varying an O 2 partial pressure. Three distinct regimes of the atomic layer evolution were experimentally observed: growth, transition and decomposition. The transition regime, at which atomic layer growth/decomposition switch takes place, is characterised by random nucleation of the atomic layers on the growing {111} surface. The decomposition starts on the side of the nanowire by removing the atomic layers without altering the overall crystal structure, which besides the fundamental importance offers new possibilities for the nanowire manipulation. Understanding of the crystal growth kinetics and nucleation at the atomic level is essential for the precise control of 1D crystal formation.
Theory and Practice in Nature Conservation - Where to Seek Sustainability?
NASA Astrophysics Data System (ADS)
Mirek, Zbigniew; Witkowski, Zbigniew
2017-12-01
Contemporary nature conservation is the subject of serious disputes, with biocentrists emphasising the superiority of the good of nature, while anthropocentrists believe that conservation space should also take account of the good of humankind. The dispute concerns two very important values perceived differently, and not resolvable within any scientifi c framework. The authors postulate a return to the Christian roots of our civilisation. It was God who gave human beings the goods He had created, expecting them to be used in line with His plan. The man who lost God's plan, destroys the life of nature as well as his own. The postulated solution is the proper shaping of conscience, to condition biodiversity conservation in line with the idea of sustainable development.
The evolution of lifespan and age-dependent cancer risk.
Rozhok, Andrii I; DeGregori, James
2016-10-01
The Armitage-Doll multi-stage model of carcinogenesis tremendously refocused cancer science by postulating that carcinogenesis is driven by a sequence of genetic changes in cells. Age-dependent cancer incidence thus has been explained in terms of the time necessary for oncogenic mutations to occur. While the multi-step nature of cancer evolution is well-supported by evidence, the mutation-centric theory is unable to explain a number of phenomena, such as the disproportion between cancer frequency and animal body size or the scaling of cancer incidence to animal lifespan. In this paper, we present a theoretical review of the current paradigm and discuss some fundamental evolutionary theory postulates that explain why cancer incidence is a function of lifespan and physiological, not chronological, aging.
Ethics in psychiatry--the patient's freedom and bondage.
Ledermann, E K
1982-01-01
Ethics is defined as the realm of the 'ought', the realm of conscience which postulates that Man has the freedom to carry out what he judges to be morally right. By such acts he realizes his freedom of making himself into a truer, more authentic person than he was before. A libertarian psychotherapy, based on this ethic, is outlined. Medical science (as all science) belongs to the realm of the 'is' and postulates that the phenomena which it studies follow a necessary course. It is therefore deterministic. In psychiatry, allowance is made for a neurological determinism in cases in which personal freedom has been diminished or abolished by mental illness, but the determinisms of behaviour therapy and of psycho-analysis are rejected by the author. PMID:7154034
Quantum probability rule: a generalization of the theorems of Gleason and Busch
NASA Astrophysics Data System (ADS)
Barnett, Stephen M.; Cresser, James D.; Jeffers, John; Pegg, David T.
2014-04-01
Busch's theorem deriving the standard quantum probability rule can be regarded as a more general form of Gleason's theorem. Here we show that a further generalization is possible by reducing the number of quantum postulates used by Busch. We do not assume that the positive measurement outcome operators are effects or that they form a probability operator measure. We derive a more general probability rule from which the standard rule can be obtained from the normal laws of probability when there is no measurement outcome information available, without the need for further quantum postulates. Our general probability rule has prediction-retrodiction symmetry and we show how it may be applied in quantum communications and in retrodictive quantum theory.
Examination of Frameworks for Safe Integration of Intelligent Small UAS into the NAS
NASA Technical Reports Server (NTRS)
Logan, Michael J.
2012-01-01
This paper discusses a proposed framework for the safe integration of small unmanned aerial systems (sUAS) into the National Airspace System (NAS). The paper briefly examines the potential uses of sUAS to build an understanding of the location and frequency of potential future flight operations based on the future applications of the sUAS systems. The paper then examines the types of systems that would be required to meet the application-level demand to determine "classes" of platforms and operations. A framework for categorization of the "intelligence" level of the UAS is postulated for purposes of NAS integration. Finally, constraints on the intelligent systems are postulated to ensure their ease of integration into the NAS.
[Animal ethics in the 19th century and Swiss animal protection law].
Bloch, I
2018-01-01
The development of animal ethics and animal rights from the antiquity up to modern times is described. The relationship of humans to animals was primarily based on fear and animal cult, developed by the domestication to a partnership. The philosophers of the early modern age denied the animals the reason, what was disadvantageous to the position of the animals in the society and the behavior of humans to the animals. By the end of the 19th century the animal protection concept developed with numerous postulates for legal regulations. With the Swiss animal protection law, which came into force in 1981, most of the postulates could be realised. It is shown, how animal protection has developed since that time.
An interfaced system for production of methane in a spacecraft
NASA Technical Reports Server (NTRS)
Weiss, A. H.
1973-01-01
The formose reaction, the homogeneously catalyzed condensation of formaldehyde to sugars, proceeds simultaneously with Cannizzaro and crossed Cannizzaro reactions. Reaction studies in a continuous stirred tank reactor have shown that rate instabilities are exhibited. There are temperature instabilities as well as concentration instabilities in calcium hydroxide catalyst, formaldehyde reactant, and hydroxyl ion. It is postulated that Ca(OH)+ is the actual catalytic species for the formose system. A unifying mechanism is developed that postulates that reactions proceed from a common intermediate complexed species, and that the selectivity for each reaction depends on the nature of the catalyst forming the carbohydrate complex. The catalytic mechanism explains the Lobry de Bruyn-van Eckenstein aldose ketose rearrangements and mutarotations of sugars that also proceed in the system.
Di Maio, Francesco; Zio, Enrico; Smith, Curtis; ...
2015-07-06
The present special issue contains an overview of the research in the field of Integrated Deterministic and Probabilistic Safety Assessment (IDPSA) of Nuclear Power Plants (NPPs). Traditionally, safety regulation for NPPs design and operation has been based on Deterministic Safety Assessment (DSA) methods to verify criteria that assure plant safety in a number of postulated Design Basis Accident (DBA) scenarios. Referring to such criteria, it is also possible to identify those plant Structures, Systems, and Components (SSCs) and activities that are most important for safety within those postulated scenarios. Then, the design, operation, and maintenance of these “safety-related” SSCs andmore » activities are controlled through regulatory requirements and supported by Probabilistic Safety Assessment (PSA).« less
2013-01-01
Background It has long been postulated that the relative abundance of specific nutrients can affect cognitive processes and emotions. Newly described influences of dietary factors on neuronal function and synaptic plasticity have revealed some of the vital mechanisms that could be responsible for the action of diet on brain health and cognitive function. Here, through a double-blind, randomized, placebo-controlled trial, we asked if the newly discovered chicken meat ingredient-168 (CMI-168) could be beneficial to the cognitive function in healthy adults. Methods Normal, healthy subjects were supplemented with either placebo or CMI-168 for 6 weeks. The subjects were given a series of cognitive tests to examine their levels of cognitive functioning at the beginning and end of supplementation, as well as two weeks after termination of supplementation. The combination of these tests, namely Digit Span Backwards, Letter-Number Sequencing, and the Rey Auditory Verbal Learning Test (RAVLT), was used to assess the subjects’ attention and working memory. For all comparisons, the probability level of p < 0.05 was taken as statistically significant using repeated measure 2-way ANOVA followed by Bonferroni post-hoc test. Results Overall, subjects supplemented with CMI-168 showed significantly (p < 0.01) better performance in all cognitive tests after 6 weeks’ supplementation compared to control and such superior performance was maintained even 2 weeks after termination of supplementation. Conclusions The present study reveals the cognition-enhancing properties of a recently developed chicken meat ingredient, likely arising from the promotion of attention and prefrontal cortex functions. PMID:23945213
Haas, David W; Bradford, Yuki; Verma, Anurag; Verma, Shefali S; Eron, Joseph J; Gulick, Roy M; Riddler, Sharon A; Sax, Paul E; Daar, Eric S; Morse, Gene D; Acosta, Edward P; Ritchie, Marylyn D
2018-05-29
We characterized associations between central nervous system (CNS) adverse events and brain neurotransmitter transporter/receptor genomics among participants randomized to efavirenz-containing regimens in AIDS Clinical Trials Group studies in the USA. Four clinical trials randomly assigned treatment-naive participants to efavirenz-containing regimens. Genome-wide genotype and PrediXcan were used to infer gene expression levels in tissues including 10 brain regions. Multivariable regression models stratified by race/ethnicity were adjusted for CYP2B6/CYP2A6 genotypes that predict plasma efavirenz exposure, age, and sex. Combined analyses also adjusted for genetic ancestry. Analyses included 167 cases with grade 2 or greater efavirenz-consistent CNS adverse events within 48 weeks of study entry, and 653 efavirenz-tolerant controls. CYP2B6/CYP2A6 genotype level was independently associated with CNS adverse events (odds ratio: 1.07; P=0.044). Predicted expression of six genes postulated to mediate efavirenz CNS side effects (SLC6A2, SLC6A3, PGR, HTR2A, HTR2B, HTR6) were not associated with CNS adverse events after correcting for multiple testing, the lowest P value being for PGR in hippocampus (P=0.012), nor were polymorphisms in these genes or AR and HTR2C, the lowest P value being for rs12393326 in HTR2C (P=6.7×10). As a positive control, baseline plasma bilirubin concentration was associated with predicted liver UGT1A1 expression level (P=1.9×10). Efavirenz-related CNS adverse events were not associated with predicted neurotransmitter transporter/receptor gene expression levels in brain or with polymorphisms in these genes. Variable susceptibility to efavirenz-related CNS adverse events may not be explained by brain neurotransmitter transporter/receptor genomics.
National Emphysema Treatment Trial redux: accentuating the positive.
Sanchez, Pablo Gerardo; Kucharczuk, John Charles; Su, Stacey; Kaiser, Larry Robert; Cooper, Joel David
2010-09-01
Under the Freedom of Information Act, we obtained the follow-up data of the National Emphysema Treatment Trial (NETT) to determine the long-term outcome for "a heterogeneous distribution of emphysema with upper lobe predominance," postulated by the NETT hypothesis to be optimal candidates for lung volume reduction surgery. Using the NETT database, we identified patients with heterogeneous distribution of emphysema with upper lobe predominance and analyzed for the first time follow-up data for those receiving lung volume reduction surgery and those receiving medical management. Furthermore, we compared the results of the NETT reduction surgery group with a previously reported consecutive case series of 250 patients undergoing bilateral lung volume reduction surgery using similar selection criteria. Of the 1218 patients enrolled, 511 (42%) conformed to the NETT hypothesis selection criteria and received the randomly assigned surgical or medical treatment (surgical = 261; medical = 250). Lung volume reduction surgery resulted in a 5-year survival benefit (70% vs 60%; P = .02). Results at 3 years compared with baseline data favored surgical reduction in terms of residual volume reduction (25% vs 2%; P < .001), University of California San Diego dyspnea score (16 vs 0 points; P < .001), and improved St George Respiratory Questionnaire quality of life score (12 points vs 0 points; P < .001). For the 513 patients with a homogeneous pattern of emphysema randomized to surgical or medical treatment, lung volume reduction surgery produced no survival advantage and very limited functional benefit. Patients most likely to benefit from lung volume reduction surgery have heterogeneously distributed emphysema involving the upper lung zones predominantly. Such patients in the NETT trial had results nearly identical to those previously reported in a nonrandomized series of similar patients undergoing lung volume reduction surgery. 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.
Abdallah, Faraj W; Johnson, James; Chan, Vincent; Murgatroyd, Harry; Ghafari, Mohammad; Ami, Noam; Jin, Rongyu; Brull, Richard
2015-01-01
Perineural dexamethasone prolongs the duration of single-injection peripheral nerve block when added to the local anesthetic solution. Postulated systemic mechanisms of action along with theoretical safety concerns have prompted the investigation of intravenous dexamethasone as an alternative, with decidedly mixed results. We aimed to confirm that addition of intravenous dexamethasone will prolong the duration of analgesia after single-injection supraclavicular block compared with conventional long-acting local anesthetic alone or in combination with perineural dexamethasone for ambulatory upper extremity surgery. Seventy-five patients were randomized to receive supraclavicular block using 30-mL bupivacaine 0.5% alone (Control), with concomitant intravenous dexamethasone 8 mg (DexIV), or with perineural dexamethasone 8 mg (DexP). Duration of analgesia was designated as the primary outcome. To test our hypothesis, the superiority of DexIV was first compared with Control and then with DexP. Motor block duration, pain scores, opioid consumption, opioid-related side effects, patient satisfaction, and block-related complications were also analyzed. Twenty-five patients per group were analyzed. The duration of analgesia (mean [95% confidence interval]) was prolonged in the DexIV group(25 hours [17.6–32.4]) compared with Control (13.2 hours [11.5–15.0]; P < 0.001) but similar to the DexP group (25 hours[19.5–30.5]; P = 1). [corrected] Both DexIV and DexP had reduced pain scores, reduced postoperative opioid consumption, and improved satisfaction compared with Control. In a single-injection supraclavicular block with long-acting local anesthetic, the effectiveness of intravenous dexamethasone in prolonging the duration of analgesia seems similar to perineural dexamethasone.
Demark-Wahnefried, Wendy; Polascik, Thomas J.; George, Stephen L.; Switzer, Boyd R.; Madden, John F.; Ruffin, Mack T.; Snyder, Denise C.; Owzar, Kouros; Hars, Vera; Albala, David M.; Walther, Philip J.; Robertson, Cary N.; Moul, Judd W.; Dunn, Barbara K.; Brenner, Dean; Minasian, Lori; Stella, Philip; Vollmer, Robin T.
2009-01-01
Background Prostate cancer affects one-out-of-six men during their lifetime. Dietary factors are postulated to influence the development and progression of prostate cancer. Low-fat diets and flaxseed supplementation may offer potentially protective strategies. Methods We undertook a multi-site, randomized controlled trial to test the effects of low-fat and/or flaxseed-supplemented diets on the biology of the prostate and other biomarkers. Prostate cancer patients (n=161) scheduled at least 21 days before prostatectomy were randomly assigned to one of the following arms: 1) control (usual diet); 2) flaxseed-supplemented diet (30 g/day); 2) low-fat diet (<20% total energy); or 4) flaxseed-supplemented, low-fat diet. Blood was drawn at baseline and prior to surgery and analyzed for prostate specific antigen (PSA), sex hormone binding globulin, testosterone, insulin-like growth factor-1 and binding protein-3, c-reactive protein, and total and low density lipoprotein cholesterol. Tumors were assessed for proliferation (Ki-67, the primary endpoint) and apoptosis. Results Men were on protocol an average of 30 days. Proliferation rates were significantly lower (P < 0.002) among men assigned to the flaxseed arms. Median Ki-67 positive cells/total nuclei ratios (x100) were 1.66 (flaxseed-supplemented diet) and 1.50 (flaxseed-supplemented, low-fat diet) vs. 3.23 (control) and 2.56 (low-fat diet). No differences were observed between arms with regard to side effects, apoptosis, and most serological endpoints; however, men on low-fat diets experienced significant decreases in serum cholesterol (P=0.048). Conclusions Findings suggest that flaxseed is safe, and associated with biologic alterations that may be protective for prostate cancer. Data also further support low-fat diets to manage serum cholesterol. PMID:19064574
Effective declutter of complex flight displays using stereoptic 3-D cueing
NASA Technical Reports Server (NTRS)
Parrish, Russell V.; Williams, Steven P.; Nold, Dean E.
1994-01-01
The application of stereo technology to new, integrated pictorial display formats has been effective in situational awareness enhancements, and stereo has been postulated to be effective for the declutter of complex informational displays. This paper reports a full-factorial workstation experiment performed to verify the potential benefits of stereo cueing for the declutter function in a simulated tracking task. The experimental symbology was designed similar to that of a conventional flight director, although the format was an intentionally confused presentation that resulted in a very cluttered dynamic display. The subject's task was to use a hand controller to keep a tracking symbol, an 'X', on top of a target symbol, another X, which was being randomly driven. In the basic tracking task, both the target symbol and the tracking symbol were presented as red X's. The presence of color coding was used to provide some declutter, thus making the task more reasonable to perform. For this condition, the target symbol was coded red, and the tracking symbol was coded blue. Noise conditions, or additional clutter, were provided by the inclusion of randomly moving, differently colored X symbols. Stereo depth, which was hypothesized to declutter the display, was utilized by placing any noise in a plane in front of the display monitor, the tracking symbol at screen depth, and the target symbol behind the screen. The results from analyzing the performances of eight subjects revealed that the stereo presentation effectively offsets the cluttering effects of both the noise and the absence of color coding. The potential of stereo cueing to declutter complex informational displays has therefore been verified; this ability to declutter is an additional benefit from the application of stereoptic cueing to pictorial flight displays.
Cip, Johannes; Widemschek, Mark; Benesch, Thomas; Waibel, Roman; Martin, Arno
2013-04-01
Mechanical autotransfusion systems for washed shed blood (WSB) were introduced to reduce the need for postoperative allogenic blood transfusions (ABTs). Although some authors have postulated decreased requirements for ABT by using autologous retransfusion devices, other trials, mostly evaluating retransfusion devices for unwashed shed blood (USB), verified a small or no benefit in reducing the need for postoperative ABT. Because of these contradictory findings it is still unclear whether autologous retransfusion systems for WSB can reduce transfusion requirements. We therefore asked whether one such autologous transfusion system for WSB can reduce the requirements for postoperative ABT. In a prospective, randomized, controlled study, we enrolled 151 patients undergoing TKA. In Group A (n=76 patients), the autotransfusion system was used for a total of 6 hours (intraoperatively and postoperatively) and the WSB was retransfused after processing. In Control Group B (n=75 patients), a regular drain without suction was used. We used signs of anemia and/or a hemoglobin value less than 8 g/dL as indications for transfusion. If necessary, we administered one or two units of allogenic blood. Twenty-three patients (33%) in Group A, who received an average of 283 mL (range, 160-406 mL) of salvaged blood, needed a mean of 2.1 units of allogenic blood, compared with 23 patients (33%) in Control Group B who needed a mean of 2.1 units of allogenic blood. We found the use of an autotransfusion system did not reduce the rate of postoperative ABTs. Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Diener, Markus K; Seiler, Christoph M; Rossion, Inga; Kleeff, Jörg; Glanemann, Matthias; Butturini, Giovanni; Tomazic, Ales; Bruns, Christiane J; Busch, Olivier R C; Farkas, Stefan; Belyaev, Orlin; Neoptolemos, John P; Halloran, Christopher; Keck, Tobias; Niedergethmann, Marco; Gellert, Klaus; Witzigmann, Helmut; Kollmar, Otto; Langer, Peter; Steger, Ulrich; Neudecker, Jens; Berrevoet, Frederik; Ganzera, Silke; Heiss, Markus M; Luntz, Steffen P; Bruckner, Thomas; Kieser, Meinhard; Büchler, Markus W
2011-04-30
The ideal closure technique of the pancreas after distal pancreatectomy is unknown. We postulated that standardised closure with a stapler device would prevent pancreatic fistula more effectively than would a hand-sewn closure of the remnant. This multicentre, randomised, controlled, parallel group-sequential superiority trial was done in 21 European hospitals. Patients with diseases of the pancreatic body and tail undergoing distal pancreatectomy were eligible and were randomly assigned by central randomisation before operation to either stapler or hand-sewn closure of the pancreatic remnant. Surgical performance was assessed with intraoperative photo documentation. The primary endpoint was the combination of pancreatic fistula and death until postoperative day 7. Patients and outcome assessors were masked to group assignment. Interim and final analysis were by intention to treat in all patients in whom a left resection was done. This trial is registered, ISRCTN18452029. Between Nov 16, 2006, and July 3, 2009, 450 patients were randomly assigned to treatment groups (221 stapler; 229 hand-sewn closure), of whom 352 patients (177 stapler, 175 hand-sewn closure) were analysed. Pancreatic fistula rate or mortality did not differ between stapler (56 [32%] of 177) and hand-sewn closure (49 [28%] of 175; OR 0·84, 95% CI 0·53–1·33; p=0·56). One patient died within the fi rst 7 days after surgery in the hand-sewn group; no deaths occurred in the stapler group. Serious adverse events did not differ between groups. Stapler closure did not reduce the rate of pancreatic fistula compared with hand-sewn closure for distal pancreatectomy. New strategies, including innovative surgical techniques, need to be identified to reduce this adverse outcome. German Federal Ministry of Education and Research.
Freese, John P; Jorgenson, Dawn B; Liu, Ping-Yu; Innes, Jennifer; Matallana, Luis; Nammi, Krishnakant; Donohoe, Rachael T; Whitbread, Mark; Silverman, Robert A; Prezant, David J
2013-08-27
Ventricular fibrillation (VF) waveform properties have been shown to predict defibrillation success and outcomes among patients treated with immediate defibrillation. We postulated that a waveform analysis algorithm could be used to identify VF unlikely to respond to immediate defibrillation, allowing selective initial treatment with cardiopulmonary resuscitation in an effort to improve overall survival. In a multicenter, double-blind, randomized study, out-of-hospital cardiac arrest patients in 2 urban emergency medical services systems were treated with automated external defibrillators using either a VF waveform analysis algorithm or the standard shock-first protocol. The VF waveform analysis used a predefined threshold value below which return of spontaneous circulation (ROSC) was unlikely with immediate defibrillation, allowing selective treatment with a 2-minute interval of cardiopulmonary resuscitation before initial defibrillation. The primary end point was survival to hospital discharge. Secondary end points included ROSC, sustained ROSC, and survival to hospital admission. Of 6738 patients enrolled, 987 patients with VF of primary cardiac origin were included in the primary analysis. No immediate or long-term survival benefit was noted for either treatment algorithm (ROSC, 42.5% versus 41.2%, P=0.70; sustained ROSC, 32.4% versus 33.4%, P=0.79; survival to admission, 34.1% versus 36.4%, P=0.46; survival to hospital discharge, 15.6% versus 17.2%, P=0.55, respectively). Use of a waveform analysis algorithm to guide the initial treatment of out-of-hospital cardiac arrest patients presenting in VF did not improve overall survival compared with a standard shock-first protocol. Further study is recommended to examine the role of waveform analysis for the guided management of VF.
Behavioral migraine management modifies behavioral and cognitive coping in people with migraine.
Seng, Elizabeth K; Holroyd, Kenneth A
2014-10-01
This is a secondary analysis of a randomized clinical trial which aims to examine changes in cognitive and behavioral responses to migraine with cognitive behavioral treatment for migraine, preventive medication for migraine, and their combination, and the relationship between these changes and reductions in migraine-related disability. Cognitive behavioral treatment is thought to reduce migraine-related disability through modifying maladaptive cognitive and behavioral responses to migraine. Two hundred thirty-two people with migraine who did not respond to 5 weeks of optimized acute therapy were randomized into a 2 (beta-blocker vs placebo) X 2 (behavioral migraine management [BMM] vs no BMM) treatment design. Participants received BMM and/or beta-blocker dose adjustment for 4 months, and were followed for an additional 12 months. Participants completed measures of catastrophizing, behavioral coping, and migraine-related disability throughout the study. Compared to drug therapy only, BMM demonstrated larger decreases in catastrophizing scores (19.16 to 9.89 vs 16.78 to 11.84, P < .001) and increases in number of positive coping strategies (proactive: 1.09 to 1.90 vs 1.16 to 1.09, P < .001; anticipatory: 0.19 to 0.69 vs 0.10 to 0.08, P < .001; migraine management: 0.14 to 0.36 vs 0.04 to 0.04, P < .001) at the end of the follow-up period. Decreases in catastrophizing were associated with a larger BMM effect on migraine-related disability (P = .036). This study demonstrated that BMM modified important cognitive and behavioral factors postulated to be mechanisms of cognitive behavioral treatments for migraine. © 2014 American Headache Society.
Trehan, Indi; Shulman, Robert J.; Ou, Ching-Nan; Maleta, Kenneth; Manary, Mark J.
2009-01-01
OBJECTIVES Tropical enteropathy is characterized by an increased urinary lactulose-to-mannitol (L:M) ratio on a site-specific sugar absorption test and is associated with increased intestinal permeability and decreased nutrient absorptive capacity. The etiology of tropical enteropathy is postulated to be intestinal bacterial overgrowth. This study tested the hypothesis that treatment with a nonabsorbable, broad-spectrum antibiotic, rifaximin, reduces the L:M ratio in rural Malawian children, among whom tropical enteropathy is common. METHODS All children aged 3–5 years from one village were enrolled in a randomized, double-blind, placebo-controlled trial of treatment with rifaximin for 7 days. The L:M ratio was measured before and after treatment, and the change in the L:M ratio was the primary outcome. Secondary outcomes were changes in the urinary sucrose-to-lactulose (SUC:L) and sucralose-to-lactulose (SCL:L) ratios, as well as changes in the fractions of each test sugar recovered in the urine. RESULTS A total of 144 children participated in this study, of whom 76% had an elevated L:M ratio on enrollment (L:M≥0.10). Children who received rifaximin did not show an improvement in their L:M ratio compared with those who received placebo (−0.01±0.12 vs. 0.02±0.16, respectively, P = 0.51, mean±s.d.), nor were there significant differences between the two groups in excretion of lactulose, mannitol, sucralose, or sucrose, or in the SUC:L and SCL:L ratios. CONCLUSIONS Rifaximin had no effect on the tropical enteropathy of 3–5-year-old Malawian children, suggesting that small-bowel bacterial overgrowth is not an important etiological factor in this condition. PMID:19491826
Tan, Tricia; Behary, Preeshila; Tharakan, George; Minnion, James; Al-Najim, Werd; Albrechtsen, Nicolai J. Wewer; Holst, Jens J.
2017-01-01
Background: Roux-en-Y gastric bypass (RYGB) surgery is currently the most effective treatment of obesity, although limited by availability and operative risk. The gut hormones Glucagon-like peptide-1 (GLP-1), Peptide YY (PYY), and Oxyntomodulin (OXM) are elevated postprandially after RYGB, which has been postulated to contribute to its metabolic benefits. Objective: We hypothesized that infusion of the three gut hormones to achieve levels similar to those encountered postprandially in RYGB patients might be effective in suppressing appetite. The aim of this study was to investigate the effect of a continuous infusion of GLP-1, OXM, and PYY (GOP) on energy intake and expenditure in obese volunteers. Methods: Obese volunteers were randomized to receive an infusion of GOP or placebo in a single-blinded, randomized, placebo-controlled crossover study for 10.5 hours a day. This was delivered subcutaneously using a pump device, allowing volunteers to remain ambulatory. Ad libitum food intake studies were performed during the infusion, and energy expenditure was measured using a ventilated hood calorimeter. Results: Postprandial levels of GLP-1, OXM, and PYY seen post RYGB were successfully matched using 4 pmol/kg/min, 4 pmol/kg/min, and 0.4 pmol/kg/min, respectively. This dose led to a mean reduction of 32% in food intake. No significant effects on resting energy expenditure were observed. Conclusion: This is, to our knowledge, the first time that an acute continuous subcutaneous infusion of GOP, replicating the postprandial levels observed after RYGB, is shown to be safe and effective in reducing food intake. This data suggests that triple hormone therapy might be a useful tool against obesity. PMID:28379519
Parkinson, Charles R; Siddiqi, Muhammad; Mason, Stephen; Lippert, Frank; Hara, Anderson T; Zero, Domenick T
2017-01-01
Calcium sodium phosphosilicate (CSPS) is a bioactive glass material that alleviates dentin hypersensitivity and is postulated to confer remineralization of caries lesions. This single-centre, randomized, single (investigator)-blind, placebo-controlled, crossover, in situ study explored whether the addition of 5% CSPS to a nonaqueous fluoride (F) such as sodium monofluorophosphate (SMFP)-containing dentifrice affects its cariostatic ability. Seventy-seven subjects wore 4 gauze-covered enamel specimens with preformed lesions (2 surface-softened and 2 subsurface) placed buccally on their mandibular bilateral dentures for up to 4 weeks. Subjects brushed twice daily with 1 of the 5 study dentifrices: 927 ppm F/5% CSPS, 927 ppm F/0% CSPS, 250 ppm F/0% CSPS, 0 ppm F/5% CSPS, or 0 ppm F/0% CSPS. Specimens were retrieved after either 21 (surface-softened lesions; analyzed by Knoop surface microhardness [SMH]) or 28 days (subsurface lesions; analyzed by transverse microradiography). The enamel fluoride uptake was determined for all specimens using a microbiopsy technique. The concentrations of fluoride and calcium in gauze-retrieved plaque were also evaluated. Higher dentifrice fluoride concentrations led to greater remineralization and fluoridation of both lesion types and increased plaque fluoride concentrations. CSPS did not improve the cariostatic properties of SMFP; there were no statistically significant differences between 927 ppm F/5% CSPS and 927 ppm F/0% CSPS in percent SMH recovery (p = 0.6788), change in integrated mineral loss (p = 0.5908), or lesion depth (p = 0.6622). Likewise, 0 ppm F/5% CSPS did not provide any benefits in comparison to 0 ppm F/0% CSPS. In conclusion, CSPS does not negatively impact nor does it improve the ability of an SMFP dentifrice to affect remineralization of caries lesions. © 2017 S. Karger AG, Basel.
75 FR 19665 - Final Regulatory Guide: Issuance, Availability
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-15
... processes, including welding, heat treating, and nondestructive testing, are controlled and accomplished by... that when stressed under operating, maintenance, testing, and postulated accident conditions (1) the...
Tan, Tony Xing; Jordan-Arthur, Brittany; Garafano, Jeffrey S; Curran, Laura
2017-01-01
We investigated 109 (79.8% female; 76% White, and 83.5% Heterosexual) mental health trainees' explicit and implicit attitudes toward heterosexual, lesbian, and gay White couples adopting and raising Black children. To determine explicit attitudes, we used a vignette depicting a Black child ready for adoption and three types of equally qualified White families who were headed by a heterosexual couple, gay couple, or lesbian couple. The trainees were asked to indicate which type of family they preferred to adopt the child. To determine implicit attitudes, we used the computer programed latency-based multifactor implicit association test (IAT) protocol. The IAT data were collected from each participant individually. Explicit data showed that over 80% of the participants indicated no strong preference in terms of which type of family should adopted the child. However, IAT data showed that the trainees implicitly preferred lesbian couples. Overall, the degree of congruence between explicit and implicit was very low. Implications for training were discussed.
Range-based volatility, expected stock returns, and the low volatility anomaly
2017-01-01
One of the foundations of financial economics is the idea that rational investors will discount stocks with more risk (volatility), which will result in a positive relation between risk and future returns. However, the empirical evidence is mixed when determining how volatility is related to future returns. In this paper, we examine this relation using a range-based measure of volatility, which is shown to be theoretically, numerically, and empirically superior to other measures of volatility. In a variety of tests, we find that range-based volatility is negatively associated with expected stock returns. These results are robust to time-series multifactor models as well as cross-sectional tests. Our findings contribute to the debate about the direction of the relationship between risk and return and confirm the presence of the low volatility anomaly, or the anomalous finding that low volatility stocks outperform high volatility stocks. In other tests, we find that the lower returns associated with range-based volatility are driven by stocks with lottery-like characteristics. PMID:29190652
Kelsen, Judith R; Baldassano, Robert N; Artis, David; Sonnenberg, Gregory F
2015-09-01
Inflammatory bowel disease (IBD) is a multifactoral disease caused by dysregulated immune responses to commensal or pathogenic microbes in the intestine, resulting in chronic intestinal inflammation. An emerging population of patients with IBD occurring before the age of 5 represent a unique form of disease, termed Very Early Onset (VEO)-IBD, which is phenotypically- and genetically-distinct from older-onset IBD. VEO-IBD is associated with increased disease severity, aggressive progression and poor responsiveness to most conventional therapies. Further investigation into the causes and pathogenesis of VEO-IBD will help improve treatment strategies, and may lead to a better understanding of the mechanisms that are essential to maintain intestinal health or provoke the development of targeted therapeutic strategies to limit intestinal disease. Here we discuss the phenotypic nature of VEO-IBD, the recent identification of novel gene variants associated with disease, and functional immunologic studies interrogating the contribution of specific genetic variants to the development of chronic intestinal inflammation.
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