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Sample records for hybrid stress general

  1. Hybrid computing - Generalities and bibliography

    International Nuclear Information System (INIS)

    Neel, Daniele

    1970-01-01

    This note presents the content of a research thesis. It describes the evolution of hybrid computing systems, discusses the benefits and shortcomings of analogue or hybrid systems, discusses the building up of an hybrid system (requires properties), comments different possible uses, addresses the issues of language and programming, discusses analysis methods and scopes of application. An appendix proposes a bibliography on these issues and notably the different scopes of application (simulation, fluid dynamics, biology, chemistry, electronics, energy, errors, space, programming languages, hardware, mechanics, and optimisation of equations or processes, physics) [fr

  2. Differential stress response of Saccharomyces hybrids revealed by monitoring Hsp104 aggregation and disaggregation.

    Science.gov (United States)

    Kempf, Claudia; Lengeler, Klaus; Wendland, Jürgen

    2017-07-01

    Proteotoxic stress may occur upon exposure of yeast cells to different stress conditions. The induction of stress response mechanisms is important for cells to adapt to changes in the environment and ensure survival. For example, during exposure to elevated temperatures the expression of heat shock proteins such as Hsp104 is induced in yeast. Hsp104 extracts misfolded proteins from aggregates to promote their refolding. We used an Hsp104-GFP reporter to analyze the stress profiles of Saccharomyces species hybrids. To this end a haploid S. cerevisiae strain, harboring a chromosomal HSP104-GFP under control of its endogenous promoter, was mated with stable haploids of S. bayanus, S. cariocanus, S. kudriavzevii, S. mikatae, S. paradoxus and S. uvarum. Stress response behaviors in these hybrids were followed over time by monitoring the appearance and dissolution of Hsp104-GFP foci upon heat shock. General stress tolerance of these hybrids was related to the growth rate detected during exposure to e.g. ethanol and oxidizing agents. We observed that hybrids were generally more resistant to high temperature and ethanol stress compared to their parental strains. Amongst the hybrids differential responses regarding the appearance of Hsp104-foci and the time required for dissolving these aggregates were observed. The S. cerevisiae/S. paradoxus hybrid, combining the two most closely related strains, performed best under these conditions. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Stress-Induced Cortisol Hampers Memory Generalization

    Science.gov (United States)

    Dandolo, Lisa C.; Schwabe, Lars

    2016-01-01

    Integrative encoding and generalization across past experiences depends largely on the hippocampus, an area known to be particularly sensitive to stress. Yet, whether stress influences the ability to generalize memories is unknown. We exposed volunteers to a stressor or a control manipulation before they completed an acquired equivalence task…

  4. Influence of Stress Shape Function on Analysis of Contact Problem Using Hybrid Photoelasticity

    International Nuclear Information System (INIS)

    Shin, Dongchul; Hawong, Jaisug

    2013-01-01

    In this research, a study on stress shape functions was conducted to analyze the contact stress problem by using a hybrid photoelasticity. Because the contact stress problem is generally solved as a half-plane problem, the relationship between two analytical stress functions, which are compositions of the Airy stress function, was similar to one of the crack problem. However, this relationship in itself could not be used to solve the contact stress problem (especially one with singular points). Therefore, to analyze the contact stress problem more correctly, stress shape functions based on the condition of two contact end points had to be considered in the form of these two analytical stress functions. The four types of stress shape functions were related to the stress singularities at the two contact end points. Among them, the primary two types used for the analysis of an O-ring were selected, and their validities were verified in this work

  5. General Stress Responses in the Honey Bee

    Directory of Open Access Journals (Sweden)

    Naïla Even

    2012-12-01

    Full Text Available The biological concept of stress originated in mammals, where a “General Adaptation Syndrome” describes a set of common integrated physiological responses to diverse noxious agents. Physiological mechanisms of stress in mammals have been extensively investigated through diverse behavioral and physiological studies. One of the main elements of the stress response pathway is the endocrine hypothalamo-pituitary-adrenal (HPA axis, which underlies the “fight-or-flight” response via a hormonal cascade of catecholamines and corticoid hormones. Physiological responses to stress have been studied more recently in insects: they involve biogenic amines (octopamine, dopamine, neuropeptides (allatostatin, corazonin and metabolic hormones (adipokinetic hormone, diuretic hormone. Here, we review elements of the physiological stress response that are or may be specific to honey bees, given the economical and ecological impact of this species. This review proposes a hypothetical integrated honey bee stress pathway somewhat analogous to the mammalian HPA, involving the brain and, particularly, the neurohemal organ corpora cardiaca and peripheral targets, including energy storage organs (fat body and crop. We discuss how this system can organize rapid coordinated changes in metabolic activity and arousal, in response to adverse environmental stimuli. We highlight physiological elements of the general stress responses that are specific to honey bees, and the areas in which we lack information to stimulate more research into how this fascinating and vital insect responds to stress.

  6. General bounds in Hybrid Natural Inflation

    Science.gov (United States)

    Germán, Gabriel; Herrera-Aguilar, Alfredo; Hidalgo, Juan Carlos; Sussman, Roberto A.; Tapia, José

    2017-12-01

    Recently we have studied in great detail a model of Hybrid Natural Inflation (HNI) by constructing two simple effective field theories. These two versions of the model allow inflationary energy scales as small as the electroweak scale in one of them or as large as the Grand Unification scale in the other, therefore covering the whole range of possible energy scales. In any case the inflationary sector of the model is of the form V(phi)=V0 (1+a cos(phi/f)) where 0waterfall field. One interesting characteristic of this model is that the slow-roll parameter epsilon(phi) is a non-monotonic function of phi presenting a maximum close to the inflection point of the potential. Because the scalar spectrum Script Ps(k) of density fluctuations when written in terms of the potential is inversely proportional to epsilon(phi) we find that Script Ps(k) presents a minimum at phimin. The origin of the HNI potential can be traced to a symmetry breaking phenomenon occurring at some energy scale f which gives rise to a (massless) Goldstone boson. Non-perturbative physics at some temperature Tmodels is not common. We use this property of HNI to determine bounds for the inflationary energy scale Δ and for the tensor-to-scalar ratio r.

  7. On generalization uniaxial stress-strain relation

    International Nuclear Information System (INIS)

    Sahay, C.; Dubey, R.N.

    1980-01-01

    Different forms of constitutive relations have been advanced for elastic, plastic and elastic-plastic behaviour of materials. It is shown that the various forms of the stress-strain relationship are specialized forms of generalization of a single stress-strain relation. For example, it is shown how the laws of elastic deformation, and the incremental and total deformation relationship for plastic behaviour are derivable from the Ramberg-Osgood relation. (orig.)

  8. Generalized rough sets hybrid structure and applications

    CERN Document Server

    Mukherjee, Anjan

    2015-01-01

    The book introduces the concept of “generalized interval valued intuitionistic fuzzy soft sets”. It presents the basic properties of these sets and also, investigates an application of generalized interval valued intuitionistic fuzzy soft sets in decision making with respect to interval of degree of preference. The concept of “interval valued intuitionistic fuzzy soft rough sets” is discussed and interval valued intuitionistic fuzzy soft rough set based multi criteria group decision making scheme is presented, which refines the primary evaluation of the whole expert group and enables us to select the optimal object in a most reliable manner. The book also details concept of interval valued intuitionistic fuzzy sets of type 2. It presents the basic properties of these sets. The book also introduces the concept of “interval valued intuitionistic fuzzy soft topological space (IVIFS topological space)” together with intuitionistic fuzzy soft open sets (IVIFS open sets) and intuitionistic fuzzy soft cl...

  9. General motors front wheel drive 2-mode hybrid transmission

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, James [General Motors Corp., Pontiac, MI (United States). New Transmission Products Group.; Holmes, Alan G. [General Motors Corp., Pontiac, MI (United States). Powertrain Hybrid Architecture

    2009-07-01

    General Motors now expands the application of two-mode hybrid technology to front wheel drive vehicles with the development of a hybrid electric transmission packaged into essentially the same space as a conventional automatic transmission for front wheel drive. This was accomplished using a space-efficient arrangement based on two planetary gear sets and electric motor-generators with large internal diameters. A combination of damper and hydraulically-controlled clutch allow comfortable shutdown and restarting of large-displacement engines in front wheel drive vehicles. The hybrid system delivers electric low-speed urban driving, two continuously variable ranges of transmission speed ratios, four fixed transmission speed ratios, electric acceleration boosting, and regenerative braking. In the first vehicle application, the two-mode hybrid helps to reduce vehicle fuel consumption by approximately one-third. (orig.)

  10. Psychological stress and multimorbidity in general practice

    DEFF Research Database (Denmark)

    Prior, Anders

    2017-01-01

    . Additionally, stress is a common reason for contacting the general practitioner (GP), and yet no guidelines for management and treatment exist. Aims The aim of this thesis was to investigate the consequences of psychological stress on the health while taking into account mental‐physical multimorbidity, i...... found to be associated with adverse health outcomes and potentially suboptimal healthcare. The link between stress and multimorbidity could substantiate the efforts to develop management guidelines for primary care, stress‐targeted interventions, and to accommodate the healthcare system to better...... and poor prognosis of physical diseases, including increased mortality. However, little is known on the physical consequences of sub‐threshold psychological stress, which is more common than psychiatric disorders in the background population and is highly prevalent in persons with multimorbidity...

  11. Multiple-time-stepping generalized hybrid Monte Carlo methods

    Energy Technology Data Exchange (ETDEWEB)

    Escribano, Bruno, E-mail: bescribano@bcamath.org [BCAM—Basque Center for Applied Mathematics, E-48009 Bilbao (Spain); Akhmatskaya, Elena [BCAM—Basque Center for Applied Mathematics, E-48009 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao (Spain); Reich, Sebastian [Universität Potsdam, Institut für Mathematik, D-14469 Potsdam (Germany); Azpiroz, Jon M. [Kimika Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P.K. 1072, Donostia (Spain)

    2015-01-01

    Performance of the generalized shadow hybrid Monte Carlo (GSHMC) method [1], which proved to be superior in sampling efficiency over its predecessors [2–4], molecular dynamics and hybrid Monte Carlo, can be further improved by combining it with multi-time-stepping (MTS) and mollification of slow forces. We demonstrate that the comparatively simple modifications of the method not only lead to better performance of GSHMC itself but also allow for beating the best performed methods, which use the similar force splitting schemes. In addition we show that the same ideas can be successfully applied to the conventional generalized hybrid Monte Carlo method (GHMC). The resulting methods, MTS-GHMC and MTS-GSHMC, provide accurate reproduction of thermodynamic and dynamical properties, exact temperature control during simulation and computational robustness and efficiency. MTS-GHMC uses a generalized momentum update to achieve weak stochastic stabilization to the molecular dynamics (MD) integrator. MTS-GSHMC adds the use of a shadow (modified) Hamiltonian to filter the MD trajectories in the HMC scheme. We introduce a new shadow Hamiltonian formulation adapted to force-splitting methods. The use of such Hamiltonians improves the acceptance rate of trajectories and has a strong impact on the sampling efficiency of the method. Both methods were implemented in the open-source MD package ProtoMol and were tested on a water and a protein systems. Results were compared to those obtained using a Langevin Molly (LM) method [5] on the same systems. The test results demonstrate the superiority of the new methods over LM in terms of stability, accuracy and sampling efficiency. This suggests that putting the MTS approach in the framework of hybrid Monte Carlo and using the natural stochasticity offered by the generalized hybrid Monte Carlo lead to improving stability of MTS and allow for achieving larger step sizes in the simulation of complex systems.

  12. Hybrid dislocated control and general hybrid projective dislocated synchronization for the modified Lue chaotic system

    International Nuclear Information System (INIS)

    Xu Yuhua; Zhou Wuneng; Fang Jianan

    2009-01-01

    This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.

  13. Hybrid dislocated control and general hybrid projective dislocated synchronization for the modified Lue chaotic system

    Energy Technology Data Exchange (ETDEWEB)

    Xu Yuhua [College of Information Science and Technology, Donghua University, Shanghai 201620 (China) and Department of Maths, Yunyang Teacher' s College, Hubei 442000 (China)], E-mail: yuhuaxu2004@163.com; Zhou Wuneng [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)], E-mail: wnzhou@163.com; Fang Jianan [College of Information Science and Technology, Donghua University, Shanghai 201620 (China)

    2009-11-15

    This paper introduces a modified Lue chaotic system, and some basic dynamical properties are studied. Based on these properties, we present hybrid dislocated control method for stabilizing chaos to unstable equilibrium and limit cycle. In addition, based on the Lyapunov stability theorem, general hybrid projective dislocated synchronization (GHPDS) is proposed, which includes complete dislocated synchronization, dislocated anti-synchronization and projective dislocated synchronization as its special item. The drive and response systems discussed in this paper can be strictly different dynamical systems (including different dimensional systems). As examples, the modified Lue chaotic system, Chen chaotic system and hyperchaotic Chen system are discussed. Numerical simulations are given to show the effectiveness of these methods.

  14. Adult Hippocampal Neurogenesis, Fear Generalization, and Stress

    Science.gov (United States)

    Besnard, Antoine; Sahay, Amar

    2016-01-01

    The generalization of fear is an adaptive, behavioral, and physiological response to the likelihood of threat in the environment. In contrast, the overgeneralization of fear, a cardinal feature of posttraumatic stress disorder (PTSD), manifests as inappropriate, uncontrollable expression of fear in neutral and safe environments. Overgeneralization of fear stems from impaired discrimination of safe from aversive environments or discernment of unlikely threats from those that are highly probable. In addition, the time-dependent erosion of episodic details of traumatic memories might contribute to their generalization. Understanding the neural mechanisms underlying the overgeneralization of fear will guide development of novel therapeutic strategies to combat PTSD. Here, we conceptualize generalization of fear in terms of resolution of interference between similar memories. We propose a role for a fundamental encoding mechanism, pattern separation, in the dentate gyrus (DG)–CA3 circuit in resolving interference between ambiguous or uncertain threats and in preserving episodic content of remote aversive memories in hippocampal–cortical networks. We invoke cellular-, circuit-, and systems-based mechanisms by which adult-born dentate granule cells (DGCs) modulate pattern separation to influence resolution of interference and maintain precision of remote aversive memories. We discuss evidence for how these mechanisms are affected by stress, a risk factor for PTSD, to increase memory interference and decrease precision. Using this scaffold we ideate strategies to curb overgeneralization of fear in PTSD. PMID:26068726

  15. Hybrid-source impedance network and its generalized cascading concepts

    DEFF Research Database (Denmark)

    Li, Ding; Gao, Feng; Loh, Poh Chiang

    2009-01-01

    Hybrid-source impedance networks have attracted attention among researchers because of their flexibility in performing buck-boost energy conversion. To date, three distinct types of impedance networks can be summarized for implementing voltage-type inverters, with another three types summarized...... for current-type inverters. These impedance networks can in principle be combined into a single generic network entity, before generalized cascading concepts are proposed for connecting multiple of them together to form energy converters with a higher output voltage gain and other unique advantages...

  16. Drought Stress Responses of Sunflower Germplasm Developed after Wide Hybridization

    Directory of Open Access Journals (Sweden)

    Roumiana Dimova Vassilevska-Ivanova

    2016-10-01

    Full Text Available Response of sunflower germplasms viz. cultivated sunflower H. annuus and two breeding lines H. annuus x T. rotundifolia and H. annuus x V. encelioides developed after wide hybridization were used for identification of drought tolerant sunflower genotypes at the seedling growth stage. Three water stress levels of zero (control, -0.4, and -0.8 MPa were developed using polyethyleneglycol-6000 (PEG-6000. Physiological and biochemical stress determining parameters such as root and shoots length, fresh weight, antioxidant enzyme activities (superoxide dismutase (SOD, catalase (CAT, guaiacol peroxidase (GPO, ascorbate peroxidase (APX and antioxidant metabolite content (total antioxidant capacity, total phenols and total flavonoids content were compared between seedlings of all three genotypes. Results revealed that sunflower genotypes have similar responses at two osmotic potentials for shoot and root length and fresh weight. The data also showed that drought stresss could induce oxidative stress, as indicated by the increase level of ascorbate peroxidase and guaiacol peroxidase at -04 MPa in H. annuus cv 1114. Although the activity of ascorbate peroxidase and guaiacol peroxidase was differentially influenced by drought, the changes of antioxidant enzyme activities such as catalase, superoxide dismutase, guaiacol peroxidase, and ascorbate peroxidase subjected to drought stress follow a similar pattern in both breeding lines, indicating that similar defense systems might be involved in the oxidative stress injury in sunflowers. Increase in content of phenols and flavonoids were detected for all three genotypes under stress, which showed that these were major antioxidant metabolites in scavenging cellular H2O2.

  17. Application of the photoelastic experimental hybrid method with new numerical method to the high stress distribution

    International Nuclear Information System (INIS)

    Hawong, Jai Sug; Lee, Dong Hun; Lee, Dong Ha; Tche, Konstantin

    2004-01-01

    In this research, the photoelastic experimental hybrid method with Hook-Jeeves numerical method has been developed: This method is more precise and stable than the photoelastic experimental hybrid method with Newton-Rapson numerical method with Gaussian elimination method. Using the photoelastic experimental hybrid method with Hook-Jeeves numerical method, we can separate stress components from isochromatics only and stress intensity factors and stress concentration factors can be determined. The photoelastic experimental hybrid method with Hook-Jeeves had better be used in the full field experiment than the photoelastic experimental hybrid method with Newton-Rapson with Gaussian elimination method

  18. Parallel adaptation of general three-dimensional hybrid meshes

    International Nuclear Information System (INIS)

    Kavouklis, Christos; Kallinderis, Yannis

    2010-01-01

    A new parallel dynamic mesh adaptation and load balancing algorithm for general hybrid grids has been developed. The meshes considered in this work are composed of four kinds of elements; tetrahedra, prisms, hexahedra and pyramids, which poses a challenge to parallel mesh adaptation. Additional complexity imposed by the presence of multiple types of elements affects especially data migration, updates of local data structures and interpartition data structures. Efficient partition of hybrid meshes has been accomplished by transforming them to suitable graphs and using serial graph partitioning algorithms. Communication among processors is based on the faces of the interpartition boundary and the termination detection algorithm of Dijkstra is employed to ensure proper flagging of edges for refinement. An inexpensive dynamic load balancing strategy is introduced to redistribute work load among processors after adaptation. In particular, only the initial coarse mesh, with proper weighting, is balanced which yields savings in computation time and relatively simple implementation of mesh quality preservation rules, while facilitating coarsening of refined elements. Special algorithms are employed for (i) data migration and dynamic updates of the local data structures, (ii) determination of the resulting interpartition boundary and (iii) identification of the communication pattern of processors. Several representative applications are included to evaluate the method.

  19. Hexahedral connection element based on hybrid-stress theory for solid structures

    International Nuclear Information System (INIS)

    Wu, D; Sze, K Y; Lo, S H

    2010-01-01

    For building structures, high-performance hybrid-stress hexahedral solid elements are excellent choices for modelling joints, beams/columns walls and thick slabs if the exact geometrical representation is required. While it is straight-forward to model beam-column structures of uniform member size with solid hexahedral elements, joining up beams and columns of various cross-sections at a common point proves to be a challenge for structural modelling using hexahedral elements with specified dimensions. In general, the joint has to be decomposed into 27 smaller solid elements to cater for the necessary connection requirements. This will inevitably increase the computational cost and introduce element distortions when elements of different sizes have to be used at the joint. Hexahedral connection elements with arbitrary specified connection interfaces will be an ideal setup to connect structural members of different sizes without increasing the number of elements or introducing highly distorted elements. In this paper, based on the hybrid-stress element theory, a general way to construct hexahedral connection element with various interfaces is introduced. Following this way, a 24-node connection element is presented and discussed in detail. Performance of the 24-node connection element equipped with different number of stress modes will be assessed with worked examples.

  20. Generalized hybrid Monte Carlo - CMFD methods for fission source convergence

    International Nuclear Information System (INIS)

    Wolters, Emily R.; Larsen, Edward W.; Martin, William R.

    2011-01-01

    In this paper, we generalize the recently published 'CMFD-Accelerated Monte Carlo' method and present two new methods that reduce the statistical error in CMFD-Accelerated Monte Carlo. The CMFD-Accelerated Monte Carlo method uses Monte Carlo to estimate nonlinear functionals used in low-order CMFD equations for the eigenfunction and eigenvalue. The Monte Carlo fission source is then modified to match the resulting CMFD fission source in a 'feedback' procedure. The two proposed methods differ from CMFD-Accelerated Monte Carlo in the definition of the required nonlinear functionals, but they have identical CMFD equations. The proposed methods are compared with CMFD-Accelerated Monte Carlo on a high dominance ratio test problem. All hybrid methods converge the Monte Carlo fission source almost immediately, leading to a large reduction in the number of inactive cycles required. The proposed methods stabilize the fission source more efficiently than CMFD-Accelerated Monte Carlo, leading to a reduction in the number of active cycles required. Finally, as in CMFD-Accelerated Monte Carlo, the apparent variance of the eigenfunction is approximately equal to the real variance, so the real error is well-estimated from a single calculation. This is an advantage over standard Monte Carlo, in which the real error can be underestimated due to inter-cycle correlation. (author)

  1. Racism-Related Stress, General Life Stress, and Psychological Functioning among Black American Women

    Science.gov (United States)

    Pieterse, Alex L.; Carter, Robert T.; Ray, Kilynda V.

    2013-01-01

    The relationship between general life stress, perceived racism, and psychological functioning was explored in a sample of 118 Black American women. Findings indicate that racism-related stress was not a significant predictor of psychological functioning when controlling for general life stress. Perceived racism was positively associated with…

  2. Hybrid determination of mixed-mode stress intensity factors on discontinuous finite-width plate by finite element and photoelasticity

    International Nuclear Information System (INIS)

    Baek, Tae Hyun; Chen, Lei; Hong, Dong Pyo

    2011-01-01

    For isotropic material structure, the stress in the vicinity of crack tip is generally much higher than the stress far away from it. This phenomenon usually leads to stress concentration and fracture of structure. Previous researches and studies show that the stress intensity factor is one of most important parameter for crack growth and propagation. This paper provides a convenient numerical method, which is called hybrid photoelasticity method, to accurately determine the stress field distribution in the vicinity of crack tip and mixed-mode stress intensity factors. The model was simulated by finite element method and isochromatic data along straight lines far away from the crack tip were calculated. By using the isochromatic data obtained from finite element method and a conformal mapping procedure, stress components and photoelastic fringes in the hybrid region were calculated. To easily compare calculated photoelastic fringes with experiment results, the fringe patterns were reconstructed, doubled and sharpened. Good agreement shows that the method presented in this paper is reliable and convenient. This method can then directly be applied to obtain mixed mode stress intensity factors from the experimentally measured isochromatic data along the straight lines

  3. Mental health, job satisfaction, and job stress among general practitioners.

    OpenAIRE

    Cooper, C. L.; Rout, U.; Faragher, B.

    1989-01-01

    OBJECTIVE--To identify sources of job stress associated with high levels of job dissatisfaction and negative mental wellbeing among general practitioners in England. DESIGN--Multivariate analysis of large database of general practitioners compiled from results of confidential questionnaire survey. Data obtained on independent variables of job stress, demographic factors, and personality. Dependent variables were mental health, job satisfaction, alcohol consumption, and smoking. SETTING--Natio...

  4. Relationship between general intelligence, emotional intelligence, stress levels and stress reactivity.

    Science.gov (United States)

    Singh, Yogesh; Sharma, Ratna

    2012-07-01

    Stressful life events and daily life stresses have both deleterious and cumulative effects on human body. In several studies, stress has been shown to affect various parameter of higher mental function like attention, concentration, learning and memory. Present study was designed to explore the relationship among GI level, EI level, psychological stress levels and acute stress reactivity in young normal healthy subjects. The study was conducted on thirty four healthy male student volunteers to study a) acute stress reactivity in subjects with varying levels of General Intelligence (GI) and Emotional Intelligence (EI) and b) correlation between GI, EI, acute stress and perceived stress. Baseline GI and EI and acute stress and perceived stress scores were measured by standard assessment scales. Using median value of GI and EI scores as cutoff values, subjects were categorized into four groups. Among different GI-EI groups, acute stress reactivity was similar but salivary Cortisol (especially post stressor level) and perceived stress level was a differentiating factor. High level of EI was associated inversely with acute and chronic perceived stress level. Significant correlation was found between acute and chronic perceived stress levels. Level of general intelligence showed no relation to acute or chronic stress levels as well as acute stress reactivity. The differences in various groups of GI and EI had no effect on the baseline and post stress performance on Sternberg memory test and all the three conditions of Stroop test. In conclusion emotional intelligence as an attribute is better suited to handle day to day acute stress and chronic perceived stress.

  5. Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response

    Directory of Open Access Journals (Sweden)

    Jos F. Brosschot

    2018-03-01

    Full Text Available Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always “on” but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

  6. Generalized Unsafety Theory of Stress: Unsafe Environments and Conditions, and the Default Stress Response.

    Science.gov (United States)

    Brosschot, Jos F; Verkuil, Bart; Thayer, Julian F

    2018-03-07

    Prolonged physiological stress responses form an important risk factor for disease. According to neurobiological and evolution-theoretical insights the stress response is a default response that is always "on" but inhibited by the prefrontal cortex when safety is perceived. Based on these insights the Generalized Unsafety Theory of Stress (GUTS) states that prolonged stress responses are due to generalized and largely unconsciously perceived unsafety rather than stressors. This novel perspective necessitates a reconstruction of current stress theory, which we address in this paper. We discuss a variety of very common situations without stressors but with prolonged stress responses, that are not, or not likely to be caused by stressors, including loneliness, low social status, adult life after prenatal or early life adversity, lack of a natural environment, and less fit bodily states such as obesity or fatigue. We argue that in these situations the default stress response may be chronically disinhibited due to unconsciously perceived generalized unsafety. Also, in chronic stress situations such as work stress, the prolonged stress response may be mainly caused by perceived unsafety in stressor-free contexts. Thus, GUTS identifies and explains far more stress-related physiological activity that is responsible for disease and mortality than current stress theories.

  7. General concept of a gas engine for a hybrid vehicle, operating on methanol dissociation products

    International Nuclear Information System (INIS)

    Tartakovsky, L.; Aleinikov, Y.; Fainberg, V.; Garbar, A.; Gutman, M.; Hetsroni, G.; Schindler, Y.; Zvirin, Y.

    1998-01-01

    The paper presents a general concept of a hybrid propulsion system, based on an SI internal combustion engine fueled by methanol dissociation products (MDP). The proposed hybrid propulsion scheme is a series hybrid, which allows the engine to be operated in an on-off mode at constant optimal regime. The engine is fed by gaseous products of methanol dissociation (mainly hydrogen and carbon monoxide) emerging from an on-board catalytic reformer. The general scheme and base operation features of the propulsion system are described. The benefits that may be achieved by combining the well-known idea of on-board methanol dissociation with the hybrid vehicle concept are discussed. The proposed scheme is compared with those of systems operating on gasoline, liquid methanol, hydrogen and also with the multi-regime (not hybrid) engine fed by MDP

  8. Constraints on stress-energy perturbations in general relativity

    International Nuclear Information System (INIS)

    Traschen, J.

    1985-01-01

    Conditions are found for the existence of integral constraints on stress-energy perturbations in general relativity. The integral constraints can be thought of as a general-relativistic generalization of the conservation of energy and momentum of matter perturbations in special relativity. The constraints are stated in terms of a vector field V, and the Robertson-Walker spacetimes are shown to have such constraint vectors. Although in general V is not a Killing vector, in a vacuum spacetime the constraint vectors are precisely the Killing vectors

  9. some generalized two-step block hybrid numerov method for solving ...

    African Journals Online (AJOL)

    Nwokem et al.

    ABSTRACT. This paper proposes a class of generalized two-step Numerov methods, a block hybrid type for the direct solution of general second order ordinary differential equations. Both the main method and additional methods were derived via interpolation and collocation procedures. The basic properties of zero ...

  10. Transgenerational stress memory is not a general response in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Ales Pecinka

    Full Text Available Adverse conditions can trigger DNA damage as well as DNA repair responses in plants. A variety of stress factors are known to stimulate homologous recombination, the most accurate repair pathway, by increasing the concentration of necessary enzymatic components and the frequency of events. This effect has been reported to last into subsequent generations not exposed to the stress. To establish a basis for a genetic analysis of this transgenerational stress memory, a broad range of treatments was tested for quantitative effects on homologous recombination in the progeny. Several Arabidopsis lines, transgenic for well-established recombination traps, were exposed to 10 different physical and chemical stress treatments, and scored for the number of somatic homologous recombination (SHR events in the treated generation as well as in the two subsequent generations that were not treated. These numbers were related to the expression level of genes involved in homologous recombination and repair. SHR was enhanced after the majority of treatments, confirming previous data and adding new effective stress types, especially interference with chromatin. Compounds that directly modify DNA stimulated SHR to values exceeding previously described induction rates, concomitant with an induction of genes involved in SHR. In spite of the significant stimulation in the stressed generations, the two subsequent non-treated generations only showed a low and stochastic increase in SHR that did not correlate with the degree of stimulation in the parental plants. Transcripts coding for SHR enzymes generally returned to pre-treatment levels in the progeny. Thus, transgenerational effects on SHR frequency are not a general response to abiotic stress in Arabidopsis and may require special conditions.

  11. Solution of the generalized Emden-Fowler equations by the hybrid functions method

    International Nuclear Information System (INIS)

    Tabrizidooz, H R; Marzban, H R; Razzaghi, M

    2009-01-01

    In this paper, we present a numerical algorithm for solving the generalized Emden-Fowler equations, which have many applications in mathematical physics and astrophysics. The method is based on hybrid functions approximations. The properties of hybrid functions, which consist of block-pulse functions and Lagrange interpolating polynomials, are presented. These properties are then utilized to reduce the computation of the generalized Emden-Fowler equations to a system of nonlinear equations. The method is easy to implement and yields very accurate results.

  12. A novel hybrid stress-function finite element method immune to severe mesh distortion

    International Nuclear Information System (INIS)

    Cen Song; Zhou Mingjue; Fu Xiangrong

    2010-01-01

    This paper introduces a hybrid stress-function finite element method proposed recently for developing 2D finite element models immune to element shapes. Deferent from the first version of the hybrid-stress element constructed by Pian, the stress function φ of 2D elastic or fracture problem is regarded as the functional variable of the complementary energy functional. Then, the basic analytical solutions of φ are taken as the trial functions for finite element models, and meanwhile, the corresponding unknown stress-function constants are introduced. By using the principle of minimum complementary energy, these unknown stress-function constants can be expressed in terms of the displacements along element edges. Finally, the complementary energy functional can be rewritten in terms of element nodal displacement vector, and thus, the element stiffness matrix of such hybrid-function element can be obtained. As examples, two (8- and 12-node) quadrilateral plane elements and an arbitrary polygonal crack element are constructed by employing different basic analytical solutions of different stress functions. Numerical results show that, the 8- and 12-node plane models can produce the exact solutions for pure bending and linear bending problems, respectively, even the element shape degenerates into triangle and concave quadrangle; and the crack element can also predict accurate results with very low computational cost in analysis of stress-singularity problems.

  13. Bearing Stress at Failure of Double-Lap Hybrid Joints in Woven Fabric Kenaf Fiber Composite Plates under Quasi-static Loading

    Directory of Open Access Journals (Sweden)

    Lee Sim Yee

    2017-01-01

    Full Text Available The present paper is focused on the bearing stress at failure of double-lap woven fabric kenaf fiber reinforced polymer (KFRP hybrid bonded-bolted joints in experimental frameworks. The effects of different normalized plate width (plate width/hole diameter, W/d, lay-up types and bolt loads were incorporated in current study as specified in testing series. Generally, hybrid joint coupons separated within adhesive layer prior to net-tension failure or bearing/net-tension failure. The bearing stress at failure increased as W/d ratio increment, critical W/d is given as four and three in clamped and finger tight condition respectively. Lay-up types present insignificant effect to bearing stress at failure due to low volume fiber fraction in kenaf fiber composites. Combination of thicker and clamped conditions plate demonstrated greater bearing stress than equivalent finger-tight (FT conditions due to higher load transferred from friction, as expected.

  14. Studies on Screening of Maize (Zea mays L.) Hybrids under Drought Stress Conditions

    OpenAIRE

    Zahoor Ahmad

    2015-01-01

    Drought is one of the most serious problems posing a grave threat to cereals production including maize. Two experiments (lab and wire house) were conducted to screen out the most tolerant and most sensitive maize hybrids (7386, 6525, Hycorn, 9696, 32B33, 3672, MMRI and 31P41) under artificial imposing drought stress by PEG-6000 and under water stress applied after seedling emergence. In first experiment five water stress levels such as zero (control), -0.2 MPa, -0.4 MPa, -0.6 MPa, and -0.8 M...

  15. Extension to linear dynamics for hybrid stress finite element formulation based on additional displacements

    Science.gov (United States)

    Sumihara, K.

    Based upon legitimate variational principles, one microscopic-macroscopic finite element formulation for linear dynamics is presented by Hybrid Stress Finite Element Method. The microscopic application of Geometric Perturbation introduced by Pian and the introduction of infinitesimal limit core element (Baby Element) have been consistently combined according to the flexible and inherent interpretation of the legitimate variational principles initially originated by Pian and Tong. The conceptual development based upon Hybrid Finite Element Method is extended to linear dynamics with the introduction of physically meaningful higher modes.

  16. Validation of the Revised Stressful Life Event Questionnaire Using a Hybrid Model of Genetic Algorithm and Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Rasoul Sali

    2013-01-01

    Full Text Available Objectives. Stressors have a serious role in precipitating mental and somatic disorders and are an interesting subject for many clinical and community-based studies. Hence, the proper and accurate measurement of them is very important. We revised the stressful life event (SLE questionnaire by adding weights to the events in order to measure and determine a cut point. Methods. A total of 4569 adults aged between 18 and 85 years completed the SLE questionnaire and the general health questionnaire-12 (GHQ-12. A hybrid model of genetic algorithm (GA and artificial neural networks (ANNs was applied to extract the relation between the stressful life events (evaluated by a 6-point Likert scale and the GHQ score as a response variable. In this model, GA is used in order to set some parameter of ANN for achieving more accurate results. Results. For each stressful life event, the number is defined as weight. Among all stressful life events, death of parents, spouse, or siblings is the most important and impactful stressor in the studied population. Sensitivity of 83% and specificity of 81% were obtained for the cut point 100. Conclusion. The SLE-revised (SLE-R questionnaire despite simplicity is a high-performance screening tool for investigating the stress level of life events and its management in both community and primary care settings. The SLE-R questionnaire is user-friendly and easy to be self-administered. This questionnaire allows the individuals to be aware of their own health status.

  17. A general range-separated double-hybrid density-functional theory.

    Science.gov (United States)

    Kalai, Cairedine; Toulouse, Julien

    2018-04-28

    A range-separated double-hybrid (RSDH) scheme which generalizes the usual range-separated hybrids and double hybrids is developed. This scheme consistently uses a two-parameter Coulomb-attenuating-method (CAM)-like decomposition of the electron-electron interaction for both exchange and correlation in order to combine Hartree-Fock exchange and second-order Møller-Plesset (MP2) correlation with a density functional. The RSDH scheme relies on an exact theory which is presented in some detail. Several semi-local approximations are developed for the short-range exchange-correlation density functional involved in this scheme. After finding optimal values for the two parameters of the CAM-like decomposition, the RSDH scheme is shown to have a relatively small basis dependence and to provide atomization energies, reaction barrier heights, and weak intermolecular interactions globally more accurate or comparable to range-separated MP2 or standard MP2. The RSDH scheme represents a new family of double hybrids with minimal empiricism which could be useful for general chemical applications.

  18. A Generalized Hybrid Multiscale Modeling Approach for Flow and Reactive Transport in Porous Media

    Science.gov (United States)

    Yang, X.; Meng, X.; Tang, Y. H.; Guo, Z.; Karniadakis, G. E.

    2017-12-01

    Using emerging understanding of biological and environmental processes at fundamental scales to advance predictions of the larger system behavior requires the development of multiscale approaches, and there is strong interest in coupling models at different scales together in a hybrid multiscale simulation framework. A limited number of hybrid multiscale simulation methods have been developed for subsurface applications, mostly using application-specific approaches for model coupling. The proposed generalized hybrid multiscale approach is designed with minimal intrusiveness to the at-scale simulators (pre-selected) and provides a set of lightweight C++ scripts to manage a complex multiscale workflow utilizing a concurrent coupling approach. The workflow includes at-scale simulators (using the lattice-Boltzmann method, LBM, at the pore and Darcy scale, respectively), scripts for boundary treatment (coupling and kriging), and a multiscale universal interface (MUI) for data exchange. The current study aims to apply the generalized hybrid multiscale modeling approach to couple pore- and Darcy-scale models for flow and mixing-controlled reaction with precipitation/dissolution in heterogeneous porous media. The model domain is packed heterogeneously that the mixing front geometry is more complex and not known a priori. To address those challenges, the generalized hybrid multiscale modeling approach is further developed to 1) adaptively define the locations of pore-scale subdomains, 2) provide a suite of physical boundary coupling schemes and 3) consider the dynamic change of the pore structures due to mineral precipitation/dissolution. The results are validated and evaluated by comparing with single-scale simulations in terms of velocities, reactive concentrations and computing cost.

  19. Transcriptional Response to Lactic Acid Stress in the Hybrid Yeast Zygosaccharomyces parabailii.

    Science.gov (United States)

    Ortiz-Merino, Raúl A; Kuanyshev, Nurzhan; Byrne, Kevin P; Varela, Javier A; Morrissey, John P; Porro, Danilo; Wolfe, Kenneth H; Branduardi, Paola

    2018-03-01

    Lactic acid has a wide range of applications starting from its undissociated form, and its production using cell factories requires stress-tolerant microbial hosts. The interspecies hybrid yeast Zygosaccharomyces parabailii has great potential to be exploited as a novel host for lactic acid production, due to high organic acid tolerance at low pH and a fermentative metabolism with a high growth rate. Here we used mRNA sequencing (RNA-seq) to analyze Z. parabailii 's transcriptional response to lactic acid added exogenously, and we explore the biological mechanisms involved in tolerance. Z. parabailii contains two homeologous copies of most genes. Under lactic acid stress, the two genes in each homeolog pair tend to diverge in expression to a significantly greater extent than under control conditions, indicating that stress tolerance is facilitated by interactions between the two gene sets in the hybrid. Lactic acid induces downregulation of genes related to cell wall and plasma membrane functions, possibly altering the rate of diffusion of lactic acid into cells. Genes related to iron transport and redox processes were upregulated, suggesting an important role for respiratory functions and oxidative stress defense. We found differences in the expression profiles of genes putatively regulated by Haa1 and Aft1/Aft2, previously described as lactic acid responsive in Saccharomyces cerevisiae Furthermore, formate dehydrogenase ( FDH ) genes form a lactic acid-responsive gene family that has been specifically amplified in Z. parabailii in comparison to other closely related species. Our study provides a useful starting point for the engineering of Z. parabailii as a host for lactic acid production. IMPORTANCE Hybrid yeasts are important in biotechnology because of their tolerance to harsh industrial conditions. The molecular mechanisms of tolerance can be studied by analyzing differential gene expression under conditions of interest and relating gene expression patterns

  20. A general method for identifying major hybrid male sterility genes in Drosophila.

    Science.gov (United States)

    Zeng, L W; Singh, R S

    1995-10-01

    The genes responsible for hybrid male sterility in species crosses are usually identified by introgressing chromosome segments, monitored by visible markers, between closely related species by continuous backcrosses. This commonly used method, however, suffers from two problems. First, it relies on the availability of markers to monitor the introgressed regions and so the portion of the genome examined is limited to the marked regions. Secondly, the introgressed regions are usually large and it is impossible to tell if the effects of the introgressed regions are the result of single (or few) major genes or many minor genes (polygenes). Here we introduce a simple and general method for identifying putative major hybrid male sterility genes which is free of these problems. In this method, the actual hybrid male sterility genes (rather than markers), or tightly linked gene complexes with large effects, are selectively introgressed from one species into the background of another species by repeated backcrosses. This is performed by selectively backcrossing heterozygous (for hybrid male sterility gene or genes) females producing fertile and sterile sons in roughly equal proportions to males of either parental species. As no marker gene is required for this procedure, this method can be used with any species pairs that produce unisexual sterility. With the application of this method, a small X chromosome region of Drosophila mauritiana which produces complete hybrid male sterility (aspermic testes) in the background of D. simulans was identified. Recombination analysis reveals that this region contains a second major hybrid male sterility gene linked to the forked locus located at either 62.7 +/- 0.66 map units or at the centromere region of the X chromosome of D. mauritiana.

  1. Modeling and Simulation of Multi-scale Environmental Systems with Generalized Hybrid Petri Nets

    Directory of Open Access Journals (Sweden)

    Mostafa eHerajy

    2015-07-01

    Full Text Available Predicting and studying the dynamics and properties of environmental systems necessitates the construction and simulation of mathematical models entailing different levels of complexities. Such type of computational experiments often require the combination of discrete and continuous variables as well as processes operating at different time scales. Furthermore, the iterative steps of constructing and analyzing environmental models might involve researchers with different background. Hybrid Petri nets may contribute in overcoming such challenges as they facilitate the implementation of systems integrating discrete and continuous dynamics. Additionally, the visual depiction of model components will inevitably help to bridge the gap between scientists with distinct expertise working on the same problem. Thus, modeling environmental systems with hybrid Petri nets enables the construction of complex processes while keeping the models comprehensible for researchers working on the same project with significantly divergent education path. In this paper we propose the utilization of a special class of hybrid Petri nets, Generalized Hybrid Petri Nets (GHPN, to model and simulate environmental systems exposing processes interacting at different time-scales. GHPN integrate stochastic and deterministic semantics as well as other types of special basic events. Moreover, a case study is presented to illustrate the use of GHPN in constructing and simulating multi-timescale environmental scenarios.

  2. Generalized syntheses of nanocrystal-graphene hybrids in high-boiling-point organic solvents.

    Science.gov (United States)

    Pang, Danny Wei-Ping; Yuan, Fang-Wei; Chang, Yan-Cheng; Li, Guo-An; Tuan, Hsing-Yu

    2012-08-07

    Nanocrystal-graphene have been proposed as a new kind of promising hybrid for a wide range of application areas including catalysts, electronics, sensors, biomedicine, and energy storage, etc. Although a variety of methods have been developed for the preparation of hybrids, a facile and general synthetic approach is still highly required. In this study, nanocrystal-graphene hybrids were successfully synthesized in high-boiling-point organic solvents. Graphene oxide (GO) nanosheets were modified by oleylamine (OLA) to form a OLA-GO complex in order to be readily incorporated into hydrophobic synthesis. A rich library of highly crystalline nanocrystals, with types including noble metal, metal oxide, magnetic material and semiconductor were successfully grown on chemically converted graphene (CCG), which is simultaneously reduced from GO during the synthesis. High boiling-point solvents afford sufficient thermal energy to assure the high-quality crystalline nature of NCs, therefore the post-annealing process is obviated. Controlled experiments revealed that OLA-GO triggers heterogeneous nucleation and serves as excellent nuclei anchorage media. The protocol developed here brings one step closer to achieve "unity in diversity" on the preparation of nanocrystal-graphene hybrids.

  3. A general model of distant hybridization reveals the conditions for extinction in Atlantic salmon and brown trout.

    Science.gov (United States)

    Quilodrán, Claudio S; Currat, Mathias; Montoya-Burgos, Juan I

    2014-01-01

    Interspecific hybridization is common in nature but can be increased in frequency or even originated by human actions, such as species introduction or habitat modification, which may threaten species persistence. When hybridization occurs between distantly related species, referred to as "distant hybridization," the resulting hybrids are generally infertile or fertile but do not undergo chromosomal recombination during gametogenesis. Here, we present a model describing this frequent but poorly studied interspecific hybridization to assess its consequences on parental species and to anticipate the conditions under which they can reach extinction. Our general model fully incorporates three important processes: density-dependent competition, dominance/recessivity inheritance of traits and assortative mating. We demonstrate its use and flexibility by assessing population extinction risk between Atlantic salmon and brown trout in Norway, whose interbreeding has recently increased due to farmed fish releases into the wild. We identified the set of conditions under which hybridization may threaten salmonid species. Thanks to the flexibility of our model, we evaluated the effect of an additional risk factor, a parasitic disease, and showed that the cumulative effects dramatically increase the extinction risk. The consequences of distant hybridization are not genetically, but demographically mediated. Our general model is useful to better comprehend the evolution of such hybrid systems and we demonstrated its importance in the field of conservation biology to set up management recommendations when this increasingly frequent type of hybridization is in action.

  4. A General Model of Distant Hybridization Reveals the Conditions for Extinction in Atlantic Salmon and Brown Trout

    Science.gov (United States)

    Quilodrán, Claudio S.; Currat, Mathias; Montoya-Burgos, Juan I.

    2014-01-01

    Interspecific hybridization is common in nature but can be increased in frequency or even originated by human actions, such as species introduction or habitat modification, which may threaten species persistence. When hybridization occurs between distantly related species, referred to as “distant hybridization,” the resulting hybrids are generally infertile or fertile but do not undergo chromosomal recombination during gametogenesis. Here, we present a model describing this frequent but poorly studied interspecific hybridization to assess its consequences on parental species and to anticipate the conditions under which they can reach extinction. Our general model fully incorporates three important processes: density-dependent competition, dominance/recessivity inheritance of traits and assortative mating. We demonstrate its use and flexibility by assessing population extinction risk between Atlantic salmon and brown trout in Norway, whose interbreeding has recently increased due to farmed fish releases into the wild. We identified the set of conditions under which hybridization may threaten salmonid species. Thanks to the flexibility of our model, we evaluated the effect of an additional risk factor, a parasitic disease, and showed that the cumulative effects dramatically increase the extinction risk. The consequences of distant hybridization are not genetically, but demographically mediated. Our general model is useful to better comprehend the evolution of such hybrid systems and we demonstrated its importance in the field of conservation biology to set up management recommendations when this increasingly frequent type of hybridization is in action. PMID:25003336

  5. A general model of distant hybridization reveals the conditions for extinction in Atlantic salmon and brown trout.

    Directory of Open Access Journals (Sweden)

    Claudio S Quilodrán

    Full Text Available Interspecific hybridization is common in nature but can be increased in frequency or even originated by human actions, such as species introduction or habitat modification, which may threaten species persistence. When hybridization occurs between distantly related species, referred to as "distant hybridization," the resulting hybrids are generally infertile or fertile but do not undergo chromosomal recombination during gametogenesis. Here, we present a model describing this frequent but poorly studied interspecific hybridization to assess its consequences on parental species and to anticipate the conditions under which they can reach extinction. Our general model fully incorporates three important processes: density-dependent competition, dominance/recessivity inheritance of traits and assortative mating. We demonstrate its use and flexibility by assessing population extinction risk between Atlantic salmon and brown trout in Norway, whose interbreeding has recently increased due to farmed fish releases into the wild. We identified the set of conditions under which hybridization may threaten salmonid species. Thanks to the flexibility of our model, we evaluated the effect of an additional risk factor, a parasitic disease, and showed that the cumulative effects dramatically increase the extinction risk. The consequences of distant hybridization are not genetically, but demographically mediated. Our general model is useful to better comprehend the evolution of such hybrid systems and we demonstrated its importance in the field of conservation biology to set up management recommendations when this increasingly frequent type of hybridization is in action.

  6. Multistep Hybrid Iterations for Systems of Generalized Equilibria with Constraints of Several Problems

    Directory of Open Access Journals (Sweden)

    Lu-Chuan Ceng

    2014-01-01

    Full Text Available We first introduce and analyze one multistep iterative algorithm by hybrid shrinking projection method for finding a solution of the system of generalized equilibria with constraints of several problems: the generalized mixed equilibrium problem, finitely many variational inclusions, the minimization problem for a convex and continuously Fréchet differentiable functional, and the fixed-point problem of an asymptotically strict pseudocontractive mapping in the intermediate sense in a real Hilbert space. We prove strong convergence theorem for the iterative algorithm under suitable conditions. On the other hand, we also propose another multistep iterative algorithm involving no shrinking projection method and derive its weak convergence under mild assumptions.

  7. Stress-strength reliability for general bivariate distributions

    Directory of Open Access Journals (Sweden)

    Alaa H. Abdel-Hamid

    2016-10-01

    Full Text Available An expression for the stress-strength reliability R=P(X1general bivariate distribution. Such distribution includes bivariate compound Weibull, bivariate compound Gompertz, bivariate compound Pareto, among others. In the parametric case, the maximum likelihood estimates of the parameters and reliability function R are obtained. In the non-parametric case, point and interval estimates of R are developed using Govindarajulu's asymptotic distribution-free method when X1 and X2 are dependent. An example is given when the population distribution is bivariate compound Weibull. Simulation is performed, based on different sample sizes to study the performance of estimates.

  8. Low speed hybrid generalized predictive control of a gasoline-propelled car.

    Science.gov (United States)

    Romero, M; de Madrid, A P; Mañoso, C; Milanés, V

    2015-07-01

    Low-speed driving in traffic jams causes significant pollution and wasted time for commuters. Additionally, from the passengers׳ standpoint, this is an uncomfortable, stressful and tedious scene that is suitable to be automated. The highly nonlinear dynamics of car engines at low-speed turn its automation in a complex problem that still remains as unsolved. Considering the hybrid nature of the vehicle longitudinal control at low-speed, constantly switching between throttle and brake pedal actions, hybrid control is a good candidate to solve this problem. This work presents the analytical formulation of a hybrid predictive controller for automated low-speed driving. It takes advantage of valuable characteristics supplied by predictive control strategies both for compensating un-modeled dynamics and for keeping passengers security and comfort analytically by means of the treatment of constraints. The proposed controller was implemented in a gas-propelled vehicle to experimentally validate the adopted solution. To this end, different scenarios were analyzed varying road layouts and vehicle speeds within a private test track. The production vehicle is a commercial Citroën C3 Pluriel which has been modified to automatically act over its throttle and brake pedals. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  9. Analyses of large quasistatic deformations of inelastic bodies by a new hybrid-stress finite element algorithm

    Science.gov (United States)

    Reed, K. W.; Atluri, S. N.

    1983-01-01

    A new hybrid-stress finite element algorithm, suitable for analyses of large, quasistatic, inelastic deformations, is presented. The algorithm is base upon a generalization of de Veubeke's complementary energy principle. The principal variables in the formulation are the nominal stress rate and spin, and thg resulting finite element equations are discrete versions of the equations of compatibility and angular momentum balance. The algorithm produces true rates, time derivatives, as opposed to 'increments'. There results a complete separation of the boundary value problem (for stress rate and velocity) and the initial value problem (for total stress and deformation); hence, their numerical treatments are essentially independent. After a fairly comprehensive discussion of the numerical treatment of the boundary value problem, we launch into a detailed examination of the numerical treatment of the initial value problem, covering the topics of efficiency, stability and objectivity. The paper is closed with a set of examples, finite homogeneous deformation problems, which serve to bring out important aspects of the algorithm.

  10. A Decoupling Control Method for Shunt Hybrid Active Power Filter Based on Generalized Inverse System

    Directory of Open Access Journals (Sweden)

    Xin Li

    2017-01-01

    Full Text Available In this paper, a novel decoupling control method based on generalized inverse system is presented to solve the problem of SHAPF (Shunt Hybrid Active Power Filter possessing the characteristics of 2-input-2-output nonlinearity and strong coupling. Based on the analysis of operation principle, the mathematical model of SHAPF is firstly built, which is verified to be invertible using interactor algorithm; then the generalized inverse system of SHAPF is obtained to connect in series with the original system so that the composite system is decoupled under the generalized inverse system theory. The PI additional controller is finally designed to control the decoupled 1-order pseudolinear system to make it possible to adjust the performance of the subsystem. The simulation results demonstrated by MATLAB show that the presented generalized inverse system strategy can realise the dynamic decoupling of SHAPF. And the control system has fine dynamic and static performance.

  11. The generalized accessibility and spectral gap of lower hybrid waves in tokamaks

    International Nuclear Information System (INIS)

    Takahashi, Hironori.

    1994-03-01

    The generalized accessibility of lower hybrid waves, primarily in the current drive regime of tokamak plasmas, which may include shifting, either upward or downward, of the parallel refractive index (n parallel ), is investigated, based upon a cold plasma dispersion relation and various geometrical constraint (G.C.) relations imposed on the behavior of n parallel . It is shown that n parallel upshifting can be bounded and insufficient to bridge a large spectral gap to cause wave damping, depending upon whether the G.C. relation allows the oblique resonance to occur. The traditional n parallel upshifting mechanism caused by the pitch angle of magnetic field lines is shown to lead to contradictions with experimental observations. An upshifting mechanism brought about by the density gradient along field lines is proposed, which is not inconsistent with experimental observations, and provides plausible explanations to some unresolved issues of lower hybrid wave theory, including generation of open-quote seed electrons.close-quote

  12. Residual Stress Measurement of SiC tile/Al7075 Hybrid Composites by Neutron Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Bok; Lee, Jun Ho; Hong, Soon Hyung; Ryu, Ho Jin [KAIST, Daejeon (Korea, Republic of); Lee, Sang Bok; Lee, Sang Kwan [Korea Institute of Materials Science, Changwon (Korea, Republic of); Muslihd, M. Rifai [Center for Advanced Materials Science and Technology, Tangerang (India)

    2016-05-15

    In this research, SiC which has low density, high compressive strength, and high elastic modulus was used to fabricate the armor plate. In addition, Al which has low density and high toughness was used for a metal matrix of the composites. If two materials are combined, the composite can be effective materials for light weight armor applications. However, the existence of a large difference in coefficients of thermal expansion (CTE) between SiC and Al matrix, SiC/Al composites can have residual stresses while cooled in the fabrication process. Previous research reported that residual stresses in the composites or microstructures have an effect on the fatigue life and their mechanical properties. Some researchers reported about the residual stresses in the SiCp/Al metal matrix composites by numerical simulation systems, X-ray diffraction, and destructive methods. In order to analyze the residual stress of SiC/Al composites, the neutron diffraction as the non-destructive method was performed in this research. The 50 vol.% SiC{sub p}/Al7075 composites and SiC tile inserted 50 vol.% SiC{sub p}/Al7075 hybrid composites were measured to analyze the residual stress of Al (111) and SiC (111). Both samples had the tensile residual stresses in the Al (111) and the compressive residual stresses in the SiC (111) due to the difference in CTE.

  13. Cloning the Gravity and Shear Stress Related Genes from MG-63 Cells by Subtracting Hybridization

    Science.gov (United States)

    Zhang, Shu; Dai, Zhong-quan; Wang, Bing; Cao, Xin-sheng; Li, Ying-hui; Sun, Xi-qing

    2008-06-01

    Background The purpose of the present study was to clone the gravity and shear stress related genes from osteoblast-like human osteosarcoma MG-63 cells by subtractive hybridization. Method MG-63 cells were divided into two groups (1G group and simulated microgravity group). After cultured for 60 h in two different gravitational environments, two groups of MG-63 cells were treated with 1.5Pa fluid shear stress (FSS) for 60 min, respectively. The total RNA in cells was isolated. The gravity and shear stress related genes were cloned by subtractive hybridization. Result 200 clones were gained. 30 positive clones were selected using PCR method based on the primers of vector and sequenced. The obtained sequences were analyzed by blast. changes of 17 sequences were confirmed by RT-PCR and these genes are related to cell proliferation, cell differentiation, protein synthesis, signal transduction and apoptosis. 5 unknown genes related to gravity and shear stress were found. Conclusion In this part of our study, our result indicates that simulated microgravity may change the activities of MG-63 cells by inducing the functional alterations of specific genes.

  14. The effect of additional equilibrium stress functions on the three-node hybrid-mixed curved beam element

    International Nuclear Information System (INIS)

    Kim, Jin Gon; Park, Yong Kuk

    2008-01-01

    To develop an effective hybrid-mixed element, it is extremely critical as to how to assume the stress field. This research article demonstrates the effect of additional equilibrium stress functions to enhance the numerical performance of the locking-free three-node hybrid-mixed curved beam element, proposed in Saleeb and Chang's previous work. It is exceedingly complicated or even infeasible to determine the stress functions to satisfy fully both the equilibrium conditions and suppression of kinematic deformation modes in the three-node hybrid-mixed formulation. Accordingly, the additional stress functions to satisfy partially or fully equilibrium conditions are incorporated in this study. Several numerical examples for static and dynamic problems confirm that the newly proposed element with these additional stress functions is highly effective regardless of the slenderness ratio and curvature of arches in static and dynamic analyses

  15. Saccharomyces interspecies hybrids as model organisms for studying yeast adaptation to stressful environments.

    Science.gov (United States)

    Lopandic, Ksenija

    2018-01-01

    The strong development of molecular biology techniques and next-generation sequencing technologies in the last two decades has significantly improved our understanding of the evolutionary history of Saccharomyces yeasts. It has been shown that many strains isolated from man-made environments are not pure genetic lines, but contain genetic materials from different species that substantially increase their genome complexity. A number of strains have been described as interspecies hybrids, implying different yeast species that under specific circumstances exchange and recombine their genomes. Such fusing usually results in a wide variety of alterations at the genetic and chromosomal levels. The observed changes have suggested a high genome plasticity and a significant role of interspecies hybridization in the adaptation of yeasts to environmental stresses and industrial processes. There is a high probability that harsh wine and beer fermentation environments, from which the majority of interspecies hybrids have been isolated so far, influence their selection and stabilization as well as their genomic and phenotypic heterogeneity. The lessons we have learned about geno- and phenotype plasticity and the diversity of natural and commercial yeast hybrids have already had a strong impact on the development of artificial hybrids that can be successfully used in the fermentation-based food and beverage industry. The creation of artificial hybrids through the crossing of strains with desired attributes is a possibility to obtain a vast variety of new, but not genetically modified yeasts with a range of improved and beneficial traits. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  16. A Novel Shape-Free Plane Quadratic Polygonal Hybrid Stress-Function Element

    Directory of Open Access Journals (Sweden)

    Pei-Lei Zhou

    2015-01-01

    Full Text Available A novel plane quadratic shape-free hybrid stress-function (HS-F polygonal element is developed by employing the principle of minimum complementary energy and the fundamental analytical solutions of the Airy stress function. Without construction of displacement interpolation function, the formulations of the new model are much simpler than those of the displacement-based polygonal elements and can be degenerated into triangular or quadrilateral elements directly. In particular, it is quite insensitive to various mesh distortions and even can keep precision when element shape is concave. Furthermore, the element does not show any spurious zero energy modes. Numerical examples show the excellent performance of the new element, denoted by HSF-AP-19β, in both displacement and stress solutions.

  17. Study of Stress Migration Failure in SiLKTM/SiO2 Hybrid Cu Interconnects

    International Nuclear Information System (INIS)

    Tsuchikawa, Haruo; Nakamura, Tomoji; Suzuki, Takashi; Mori, Hiroko; Shono, Ken

    2004-01-01

    Stress migration (SM) behavior is studied for a 130nm-node SiLK TM /SiO2 hybrid structure in which the interlevel dielectrics (ILD) consist of SiLK TM for trench levels and SiO2 for via levels. The failure rate dependence on the temperature, line width and circuit is examined in detail. Furthermore, an effect of dielectric deposition process on the reliability of the hybrid interconnects is investigated. It has been found that SM behavior is essentially similar to that reported in Cu/SiO2 systems. It has also been clarified that SiO2 PVD conditions at via level had a large impact on the failure rate. Therefore, the control of ILD deposition conditions is found to be one of the key factors in suppressing the SM failure. In order to examine the effect of the PVD conditions, the residual stress in vias were measured by using X-ray diffraction method. The results show that σx (the stress component parallel to the surface) in vias greatly depends on the PVD conditions. Then, the relationship between the PVD conditions and the SM failure rate is clarified

  18. Microstructure Characterization and Stress Corrosion Evaluation of Autogenous and Hybrid Friction Stir Welded Al-Cu-Li 2195 Alloy

    Science.gov (United States)

    Li, Zhixian; Arbegast, William J.; Meletis, Efstathios I.

    1997-01-01

    Friction stir welding process is being evaluated for application on the Al-Cu-Li 2195 Super-Light Weight External Tank of the Space Transportation System. In the present investigation Al-Cu-Li 2195 plates were joined by autogenous friction stir welding (FSW) and hybrid FSW (friction stir welding over existing variable polarity plasma arc weld). Optical microscopy and transmission electron microscopy (TEM) were utilized to characterize microstructures of the weldments processed by both welding methods. TEM observations of autogenous FSW coupons in the center section of the dynamically-recrystallized zone showed an equiaxed recrystallized microstructure with an average grain size of approx. 3.8 microns. No T(sub 1), precipitates were present in the above-mentioned zone. Instead, T(sub B) and alpha precipitates were found in this zone with a lower population. Alternate immersion, anodic polarization, constant load, and slow strain tests were carried out to evaluate the general corrosion and stress-corrosion properties of autogenous and hybrid FSW prepared coupons. The experimental results will be discussed.

  19. A comparison of generalized hybrid Monte Carlo methods with and without momentum flip

    International Nuclear Information System (INIS)

    Akhmatskaya, Elena; Bou-Rabee, Nawaf; Reich, Sebastian

    2009-01-01

    The generalized hybrid Monte Carlo (GHMC) method combines Metropolis corrected constant energy simulations with a partial random refreshment step in the particle momenta. The standard detailed balance condition requires that momenta are negated upon rejection of a molecular dynamics proposal step. The implication is a trajectory reversal upon rejection, which is undesirable when interpreting GHMC as thermostated molecular dynamics. We show that a modified detailed balance condition can be used to implement GHMC without momentum flips. The same modification can be applied to the generalized shadow hybrid Monte Carlo (GSHMC) method. Numerical results indicate that GHMC/GSHMC implementations with momentum flip display a favorable behavior in terms of sampling efficiency, i.e., the traditional GHMC/GSHMC implementations with momentum flip got the advantage of a higher acceptance rate and faster decorrelation of Monte Carlo samples. The difference is more pronounced for GHMC. We also numerically investigate the behavior of the GHMC method as a Langevin-type thermostat. We find that the GHMC method without momentum flip interferes less with the underlying stochastic molecular dynamics in terms of autocorrelation functions and it to be preferred over the GHMC method with momentum flip. The same finding applies to GSHMC

  20. Children's Abstraction and Generalization of English Lexical Stress Patterns

    Science.gov (United States)

    Redford, Melissa A.; Oh, Grace E.

    2016-01-01

    The current study investigated school-aged children's internalization of the distributional patterns of English lexical stress as a function of vocabulary size. Sixty children (5;3 to 8;3) participated in the study. The children were asked to blend two individually presented, equally stressed syllables to produce disyllabic nonwords with different…

  1. Nurses' work-related stress in China: a comparison between psychiatric and general hospitals.

    Science.gov (United States)

    Qi, Yun-Ke; Xiang, Yu-Tao; An, Feng-Rong; Wang, Jing; Zeng, Jiao-Ying; Ungvari, Gabor S; Newhouse, Robin; Yu, Doris S F; Lai, Kelly Y C; Ding, Yan-Ming; Yu, Liuyang; Zhang, Xiang-Yang; Chiu, Helen F K

    2014-01-01

    Little is known about the level of work-related stress in nurses in China.This study compared the level of work-related stress between female nurses working in psychiatric and general hospitals in China. A descriptive comparative cross-sectional design was used.A consecutive sample of nurses from two psychiatric hospitals (N = 297) and a medical unit (N = 408) of a general hospital completed a written survey including socio-demographic data and a measure of work-related stress (Nurse Stress Inventory). Compared to the nurses working in the general hospital, those working in the psychiatric setting had a higher level of stress in the domains of working environment and resources (p working experience, and working in psychiatric hospitals were associated with high work-related stress (b = .2, p work-related stress, specific stress management workshops and effective staff supportive initiatives for Chinese nurses are warranted.

  2. Identification of single nucleotide polymorphisms (SNPs) at candidate genes involved in abiotic stress in two Prosopis species of hybrids

    OpenAIRE

    Maria F. Pomponio; Susana Marcucci Poltri; Diego Lopez Lauenstein; Susana Torales

    2014-01-01

    Aim of the study: Identify and compare SNPs on candidate genes related to abiotic stress in Prosopis chilensis, Prosopis flexuosa and interspecific hybridsArea of the study: Chaco árido, Argentina. Material and Methods: Fragments from 6 candidate genes were sequenced in 60 genotypes. DNA polymorphisms were analyzed.Main Results: The analysis revealed that the hybrids had the highest rate of polymorphism, followed by P. flexuosa and P. chilensis, the values found are comparable to other forest...

  3. Construct validation of the hybrid model of posttraumatic stress disorder: Distinctiveness of the new symptom clusters.

    Science.gov (United States)

    Silverstein, Madison W; Dieujuste, Nathalie; Kramer, Lindsay B; Lee, Daniel J; Weathers, Frank W

    2018-03-01

    Despite the factor analytic support for the seven-factor hybrid model (Armour et al., 2015) of posttraumatic stress disorder (PTSD), little research has examined the degree to which newly established symptom clusters (i.e., negative affect, anhedonia, dysphoric arousal, anxious arousal, externalizing behavior) functionally and meaningfully differ in their associations with other clinical phenomena. The aim of the current study was to examine the degree to which newly established PTSD symptom clusters differentially relate to co-occurring psychopathology and related clinical phenomena through Wald testing using latent variable modeling. Participants were 535 trauma-exposed undergraduates who completed the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5; Weathers et al., 2013) and Personality Assessment Inventory (PAI; Morey, 1991). As expected and in line with results from previous studies, significant heterogeneity emerged for dysphoric arousal, anxious arousal, and externalizing behavior. However, there was less evidence for the distinctiveness of negative affect and anhedonia. Results indicate that only some of the newly established symptom clusters significantly differ in their associations with related clinical phenomena and that the hybrid model might not provide a meaningful framework for understanding which PTSD symptoms relate to associated features. Limitations include a non-clinical sample and reliance on retrospective self-report assessment measures. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Failure of Sierra White granite under general states of stress

    Science.gov (United States)

    Ingraham, M. D.; Dewers, T. A.; Lee, M.; Holdman, O.; Cheung, C.; Haimson, B. C.

    2017-12-01

    The effect of the intermediate principal stress on the failure of Sierra White granite was investigated by performing tests under true triaxial states of stress. Tests were performed under constant Lode angle conditions with Lode angles ranging from 0 to 30°, pure shear to axisymmetric compression. Results show that the failure of Sierra White granite is heavily dependent on the intermediate principal stress which became more dramatic as the mean stress increased. An analysis of the shear bands formed at failure was performed using an associated flow rule and the Rudnicki and Rice (1975) localization criteria. The localization analysis showed excellent agreement with experimental results. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  5. A Hybrid Generalized Hidden Markov Model-Based Condition Monitoring Approach for Rolling Bearings.

    Science.gov (United States)

    Liu, Jie; Hu, Youmin; Wu, Bo; Wang, Yan; Xie, Fengyun

    2017-05-18

    The operating condition of rolling bearings affects productivity and quality in the rotating machine process. Developing an effective rolling bearing condition monitoring approach is critical to accurately identify the operating condition. In this paper, a hybrid generalized hidden Markov model-based condition monitoring approach for rolling bearings is proposed, where interval valued features are used to efficiently recognize and classify machine states in the machine process. In the proposed method, vibration signals are decomposed into multiple modes with variational mode decomposition (VMD). Parameters of the VMD, in the form of generalized intervals, provide a concise representation for aleatory and epistemic uncertainty and improve the robustness of identification. The multi-scale permutation entropy method is applied to extract state features from the decomposed signals in different operating conditions. Traditional principal component analysis is adopted to reduce feature size and computational cost. With the extracted features' information, the generalized hidden Markov model, based on generalized interval probability, is used to recognize and classify the fault types and fault severity levels. Finally, the experiment results show that the proposed method is effective at recognizing and classifying the fault types and fault severity levels of rolling bearings. This monitoring method is also efficient enough to quantify the two uncertainty components.

  6. A Hybrid Generalized Hidden Markov Model-Based Condition Monitoring Approach for Rolling Bearings

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2017-05-01

    Full Text Available The operating condition of rolling bearings affects productivity and quality in the rotating machine process. Developing an effective rolling bearing condition monitoring approach is critical to accurately identify the operating condition. In this paper, a hybrid generalized hidden Markov model-based condition monitoring approach for rolling bearings is proposed, where interval valued features are used to efficiently recognize and classify machine states in the machine process. In the proposed method, vibration signals are decomposed into multiple modes with variational mode decomposition (VMD. Parameters of the VMD, in the form of generalized intervals, provide a concise representation for aleatory and epistemic uncertainty and improve the robustness of identification. The multi-scale permutation entropy method is applied to extract state features from the decomposed signals in different operating conditions. Traditional principal component analysis is adopted to reduce feature size and computational cost. With the extracted features’ information, the generalized hidden Markov model, based on generalized interval probability, is used to recognize and classify the fault types and fault severity levels. Finally, the experiment results show that the proposed method is effective at recognizing and classifying the fault types and fault severity levels of rolling bearings. This monitoring method is also efficient enough to quantify the two uncertainty components.

  7. New hybrid conjugate gradient methods with the generalized Wolfe line search.

    Science.gov (United States)

    Xu, Xiao; Kong, Fan-Yu

    2016-01-01

    The conjugate gradient method was an efficient technique for solving the unconstrained optimization problem. In this paper, we made a linear combination with parameters β k of the DY method and the HS method, and putted forward the hybrid method of DY and HS. We also proposed the hybrid of FR and PRP by the same mean. Additionally, to present the two hybrid methods, we promoted the Wolfe line search respectively to compute the step size α k of the two hybrid methods. With the new Wolfe line search, the two hybrid methods had descent property and global convergence property of the two hybrid methods that can also be proved.

  8. The factors associated to psychosocial stress among general practitioners in Lithuania. Cross-sectional study

    Directory of Open Access Journals (Sweden)

    Vanagas Giedrius

    2005-06-01

    Full Text Available Abstract Background There are number of studies showing that general practice is one of the most stressful workplace among health care workers. Since Baltic States regained independence in 1990, the reform of the health care system took place in which new role and more responsibilities were allocated to general practitioners' in Lithuania. This study aimed to explore the psychosocial stress level among Lithuanian general practitioner's and examine the relationship between psychosocial stress and work characteristics. Methods The cross-sectional study of 300 Lithuanian General practitioners. Psychosocial stress was investigated with a questionnaire based on the Reeder scale. Job demands were investigated with the R. Karasek scale. The analysis included descriptive statistics; interrelationship analysis between characteristics and multivariate logistic regression to estimate odds ratios for each of the independent variables in the model. Results Response rate 66% (N = 197. Our study highlighted highest prevalence of psychosocial stress among widowed, single and female general practitioners. Lowest prevalence of psychosocial stress was among males and older age general practitioners. Psychosocial stress occurs when job demands are high and job decision latitude is low (χ2 = 18,9; p Conclusion One half of respondents suffering from work related psychosocial stress. High psychological workload demands combined with low decision latitude has the greatest impact to stress caseness among GP's. High job demands, high patient load and young age of GP's can be assigned as significant predictors of psychosocial stress among GP's.

  9. General engineering ethics and multiple stress of atomic energy engineering

    International Nuclear Information System (INIS)

    Takeda, Kunihiko

    1999-01-01

    The factors, by which the modern engineering ethics has been profoundly affected, were classified to three categories, namely mental blow, the destruction of human function and environment damage. The role of atomic energy engineering in the ethic field has been shown in the first place. It is pointed out that it has brought about the mental blow by the elucidation of universal truth and discipline and the functional disorder by the power supply. However, the direct effect of radiation to the human kinds is only a part of the stresses comparing to the accumulation of the social stress which should be taken into account of by the possibility of disaster and the suspicion of the atomic energy politics. An increase in the multiple stresses as well as the restriction of criticism will place obstacles on the promotion of atomic energy. (author)

  10. General engineering ethics and multiple stress of atomic energy engineering

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kunihiko [Shibaura Inst. of Tech., Tokyo (Japan)

    1999-08-01

    The factors, by which the modern engineering ethics has been profoundly affected, were classified to three categories, namely mental blow, the destruction of human function and environment damage. The role of atomic energy engineering in the ethic field has been shown in the first place. It is pointed out that it has brought about the mental blow by the elucidation of universal truth and discipline and the functional disorder by the power supply. However, the direct effect of radiation to the human kinds is only a part of the stresses comparing to the accumulation of the social stress which should be taken into account of by the possibility of disaster and the suspicion of the atomic energy politics. An increase in the multiple stresses as well as the restriction of criticism will place obstacles on the promotion of atomic energy. (author)

  11. Development of nondestructive hybrid measuring method for three-dimensional residual stress distribution of thick welded joint. Hybrid measuring method of inherent strain method and neutron diffraction method

    International Nuclear Information System (INIS)

    Nakacho, Keiji; Kasahara, Norifumi; Tamura, Ryota

    2012-01-01

    The measuring methods of the residual stress are classified into destructive one and nondestructive one. The inherent strain method (ISM) is destructive one. The neutron diffraction method (NDM) is nondestructive one. But the measurable depth is limited within about 20 mm and the method cannot measure the weld zone, without destruction of the object. So, in this study, the hybrid measuring method has been developed, by combining the ISM and the NDM. The theory of the hybrid method is the same as the ISM. In the analysis, the strains measured by the NDM without destruction are used. This hybrid measuring method is a true nondestructive measuring method for a thick welded joint. The applicability of the hybrid method has been verified by simulation, using a butt welded joint of thick pipes. In the simulation, the reliable order of the strains measured by the present NDM is very important, and was considered as 10 micro. The measurable regions by the present NDM were assumed. Under the above conditions, the data (the residual elastic strains assumed to be measured by the NDM) were made, and used in the ISM. As a result of such simulation, it has been cleared that the estimated residual stress has very high accuracy, if enough data are used. The required number of data is less than the ISM. (author)

  12. Stress among general practitioners of Kwa-Dukuza, Kwa-Zulu Natal

    Directory of Open Access Journals (Sweden)

    Indiran Govender

    2009-08-01

    Method: A cross-sectional, descriptive study using a self-administered, standardised questionnaire (12-item General Health Questionnaire [GHC] was performed on the 30 general practitioners in Kwa-Dukuza. Confidentiality and anonymity were maintained. Results: 26 of the 30 GPs (87% responded to the survey. 10 GPs (38% were stressed as per the GHQ, six of whom were severely stressed. 22 reported that they felt stressed at work (subjectively. Conclusion: The results indicated that stress among Kwa-Dukuza GPs is slightly higher (38% than found in other studies that indicate a prevalence of 28% among doctors.

  13. Biochemical components and dry matter of lemon and mandarin hybrids under salt stress

    Directory of Open Access Journals (Sweden)

    Francisco V. da S. Sá

    Full Text Available ABSTRACT The objective was to study the biochemical changes and dry matter content in lemon and mandarin hybrids under salt stress during rootstock formation. For this, a study was conducted in randomized complete block, using a 2 x 5 factorial scheme, with two salinity levels (0.3 and 4.0 dS m-1 applied in five citrus rootstock genotypes (1. TSKC x CTARG - 019; 2. LRF; 3. TSKC x (LCR x TR - 040; 4. LCRSTC and 5. LVK, with three replicates and four plants per plot. At 90 days after sowing, saline treatments started to be applied and continued until 120 days after sowing, the moment in which the plants were collected for evaluation of biochemical characteristics and phytomass accumulation. The increase in water salinity negatively affected the biochemical components and dry matter accumulation of citrus genotypes. The genotypes TSKC x (LCR x TR - 040, LCRSTC and LVK were the least affected by salt stress, standing out as the materials most tolerant to salinity.

  14. Internal stress distribution of X-ring using photoelastic experimental hybrid method

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, Alunda Ouma [Dedan Kimathi University of Technology, Nyeri (Kenya); Hawong, Jai Sug; Lim, Hyun Seok [Yeungnam University, Gyeongsan (Korea, Republic of); Shin, Dong Chul [Koje College, Geoje (Korea, Republic of)

    2014-05-15

    Sealing elements are essential parts of many machines, and are used to prevent the loss of a fluid or gas. When such fluids are not properly sealed, catastrophic failures may result. Many different types of rings have been developed to suit various industrial needs. Considerable research has been done on the O-ring. We analyze the internal stresses developed in an X-ring under a uniform squeeze rate of 20%, which is suitable for static applications, using a photoelastic experimental hybrid method. The internal pressures applied were 0.98, 1.96, 2.94, 3.92, 4.90, and 5.88 MPa. We show that sealing rings with X geometry have considerably higher internal stresses than O-ring seals. In addition, we demonstrate that after extrusion, for an internal pressure of 5.88 MPa, the two lobes on the upper contact surface merge, thereby increasing the contact length of the upper side significantly. Extrusion in the X-ring occurred when the internal pressure was 4.90 MPa.

  15. [SSR analysis on stress effect of transgenic hybrid poplar 741 on Clostera anachoreta (Fabricius) (Lepidoptera: Notodontidae)].

    Science.gov (United States)

    Liu, Jun Xia; Song, Xiao Ying; Jiang, Wen Hu; Zhou, Guo Na; Gao, Bao Jia

    2016-12-01

    The genetic differentiation of the experimental population of Clostera anachoreta fed on different resistant transgenic 741 poplar leaves was analyzed by SSR molecular marker technique to investigate stress effect of transgenic poplar Bt gene as food on target insect. The experimental population of C. anachoreta fed on transgenic 741 poplar high resistant strains 'Pb29', medium resis-tant strains 'Pb17' and non-transgenic poplar (CK), and the screened ten pairs of SSR primers were used. The results showed that 76 alleles were observed in ten pairs of primers. The average allele was 7.6, the average effective number of alleles was 2.2, the average observed heterozygosity was 0.5167, the average expected heterozygosity was 0.5167, and the average percentage of polymorphic loci was 96.7%. The genetic diversity level of C. anachoreta experimental population fed on transgenic poplar 741 was significantly higher than that fed on non-transgenic populations, and C. anachoreta fed on high resistance had the lowest genetic similarity with CK samples, which showed an increasing trend of the genetic diversity of the experimental population fed on transgenic Bt poplar. It was thus clear that transgenic hybrid poplar 741 had stress effects on genetic differentiation of C. anachoreta experimental population by SSR.

  16. Spinal pain and co-occurrence with stress and general well-being among young adolescents

    DEFF Research Database (Denmark)

    Stallknecht, Sandra Elkjær; Strandberg-Larsen, Katrine; Hestbæk, Lise

    2017-01-01

    This study aims to describe the patterns in low back, mid back, and neck pain complaints in young adolescents from the Danish National Birth Cohort (DNBC) and to investigate the co-occurrence of spinal pain and stress and general well-being, respectively. Cross-sectional data from the 11-year...... follow-up of DNBC were used. As part of a web-based survey, a total of 45,371 young adolescents between 10 and 14 years old completed the Young Spine Questionnaire, the Stress in Children Questionnaire, and a one-item question on general well-being. Associations between spinal pain and, respectively......, stress and general well-being were estimated by means of multiple logistic regression models. Almost one fifth of boys and one quarter of girls reported spinal pain. Compared with adolescents who reported no stress, adolescents reporting medium and high values of stress had odds ratios (OR) of 2.19 (95...

  17. Hybrid B-Spline Collocation Method for Solving the Generalized Burgers-Fisher and Burgers-Huxley Equations

    Directory of Open Access Journals (Sweden)

    Imtiaz Wasim

    2018-01-01

    Full Text Available In this study, we introduce a new numerical technique for solving nonlinear generalized Burgers-Fisher and Burgers-Huxley equations using hybrid B-spline collocation method. This technique is based on usual finite difference scheme and Crank-Nicolson method which are used to discretize the time derivative and spatial derivatives, respectively. Furthermore, hybrid B-spline function is utilized as interpolating functions in spatial dimension. The scheme is verified unconditionally stable using the Von Neumann (Fourier method. Several test problems are considered to check the accuracy of the proposed scheme. The numerical results are in good agreement with known exact solutions and the existing schemes in literature.

  18. Biochemical response of hybrid black poplar tissue culture (Populus × canadensis) on water stress.

    Science.gov (United States)

    Popović, B M; Štajner, D; Ždero-Pavlović, R; Tari, I; Csiszár, J; Gallé, Á; Poór, P; Galović, V; Trudić, B; Orlović, S

    2017-05-01

    In this study, poplar tissue culture (hybrid black poplar, M1 genotype) was subjected to water stress influenced by polyethyleneglycol 6000 (100 and 200 mOsm PEG 6000). The aim of the research was to investigate the biochemical response of poplar tissue culture on water deficit regime. Antioxidant status was analyzed including antioxidant enzymes, superoxide-dismutase (SOD), catalase (CAT), guiacol-peroxidase (GPx), glutathione-peroxidase (GSH-Px), glutathione-reductase, reduced glutathione, total phenol content, Ferric reducing antioxidant power and DPPH radical antioxidant power. Polyphenol oxidase and phenylalanine-ammonium-lyase were determined as enzymatic markers of polyphenol metabolism. Among oxidative stress parameters lipid peroxidation, carbonyl-proteins, hydrogen-peroxide, reactive oxygen species, nitric-oxide and peroxynitrite were determined. Proline, proline-dehydrogenase and glycinebetaine were measured also as parameters of water stress. Cell viability is finally determined as a biological indicator of osmotic stress. It was found that water stress induced reactive oxygen and nitrogen species and lipid peroxidation in leaves of hybrid black poplar and reduced cell viability. Antioxidant enzymes including SOD, GPx, CAT and GSH-Px were induced but total phenol content and antioxidant capacity were reduced by PEG 6000 mediated osmotic stress. The highest biochemical response and adaptive reaction was the increase of proline and GB especially by 200 mOsm PEG. While long term molecular analysis will be necessary to fully address the poplar potentials for water stress adaptation, our results on hybrid black poplar suggest that glycine-betaine, proline and PDH enzyme might be the most important markers of poplar on water stress and that future efforts should be focused on these markers and strategies to enhance their concentration in poplar.

  19. Occupational Stress, Negative Affectivity and Physical Health in Special and General Education Teachers in Greece

    Science.gov (United States)

    Lazuras, Lambros

    2006-01-01

    Teacher stress has attracted considerable attention, yet few studies have focused on special education teachers. This article, by Lambros Lazuras of the South-East European Research Centre (SEERC) in Thessaloniki, reports research designed to explore differences in the stress levels of general and special educators in Greece and provides…

  20. Work Related Stress, Burnout, Job Satisfaction and General Health of Nurses

    OpenAIRE

    Khamisa, Natasha; Oldenburg, Brian; Peltzer, Karl; Ilic, Dragan

    2015-01-01

    Gaps in research focusing on work related stress, burnout, job satisfaction and general health of nurses is evident within developing contexts like South Africa. This study identified the relationship between work related stress, burnout, job satisfaction and general health of nurses. A total of 1200 nurses from four hospitals were invited to participate in this cross-sectional study (75% response rate). Participants completed five questionnaires and multiple linear regression analysis was us...

  1. General Series Solutions for Stresses and Displacements in an Inner-fixed Ring

    Science.gov (United States)

    Jiao, Yongshu; Liu, Shuo; Qi, Dexuan

    2018-03-01

    The general series solution approach is provided to get the stress and displacement fields in the inner-fixed ring. After choosing an Airy stress function in series form, stresses are expressed by infinite coefficients. Displacements are obtained by integrating the geometric equations. For an inner-fixed ring, the arbitrary loads acting on outer edge are extended into two sets of Fourier series. The zero displacement boundary conditions on inner surface are utilized. Then the stress (and displacement) coefficients are expressed by loading coefficients. A numerical example shows the validity of this approach.

  2. Effects of Drought Stress on Vegetative and Reproductive Stages of Forage and Kernel Corn Hybrids

    Directory of Open Access Journals (Sweden)

    M Hajibabaei

    2016-10-01

    Full Text Available Introduction Maize is one of the most important cereals which its global production is severely affected by drought in many parts of the world. One of the best ways of water management on field is to choose the proper variety which could be chosen indirectly by the traits affecting the grain yield. Materials and Methods In order to study the effect of drought stress in vegetative and reproductive stages in 14 corn hybrids, an experiment was conducted at the experimental field of Seed and Plant Improvement Institute of Karaj, in 2009. The Research Station located in 50°, 55´ eastern latitude and 35°, 47´ northern longitude with 1254 height above mean sea level (AMSL. The soil texture of the location was loam-clay with pH= 7.5 and the Electrical Capacity (EC = 0.7 dsm-1. The experiment was carried out using split-plot in a randomized complete block design (RCBD with three replications. The main plots consisted of three levels of irrigation regimes (irrigation after 70, 100 and 130 mm cumulative evaporation from evaporation pan class A and sub-plots included 14 new corn hybrids Includes eleven new hybrids such as (K47/2-2-1-4-1-1-1×MO17، K3653/2×K19، KLM76004/3-2-1-1-1-1-1-1×K3545/6، K3653/2×MO17، K74/2-2-1-2-1-1-1-1×K3545/6، K47/3-1-2-7-1-1-1×MO17، K47/2-2-1-2-2-1-1-1×K3544/1، KLM76004/3-2-1-1-1-1-1-1×K3544/1، K47/2-2-1-2-1-1-1-1×K3544/1، KLM77029/8-1-2-3-2-3×MO17 and KLM76005/2-3-1-1-1-1×MO17 and three hybrid control (KSC704, KSC720, KSC700. Irrigation time was determined using daily evaporation rate of standard class A evaporation pan. To determine the volume of water per irrigation, a sample of each plot from depth of root development was prepared before irrigation. The samples were kept in oven 80°C for 24 hours. The weight of soil moisture content was calculated and the volume of water per irrigation was calculated using equations 1 and 2. 1: H = ρb (F.C - m D 2: V = H × A Where H is the water height in the

  3. An efficient heuristic versus a robust hybrid meta-heuristic for general framework of serial-parallel redundancy problem

    International Nuclear Information System (INIS)

    Sadjadi, Seyed Jafar; Soltani, R.

    2009-01-01

    We present a heuristic approach to solve a general framework of serial-parallel redundancy problem where the reliability of the system is maximized subject to some general linear constraints. The complexity of the redundancy problem is generally considered to be NP-Hard and the optimal solution is not normally available. Therefore, to evaluate the performance of the proposed method, a hybrid genetic algorithm is also implemented whose parameters are calibrated via Taguchi's robust design method. Then, various test problems are solved and the computational results indicate that the proposed heuristic approach could provide us some promising reliabilities, which are fairly close to optimal solutions in a reasonable amount of time.

  4. Relationship between stress coping and sleep disorders among the general Japanese population: a nationwide representative survey.

    Science.gov (United States)

    Otsuka, Yuichiro; Kaneita, Yoshitaka; Itani, Osamu; Nakagome, Sachi; Jike, Maki; Ohida, Takashi

    2017-09-01

    To clarify the prevalence of stress, and examine the relationship between sleep disorders and stress coping strategies among highly stressed individuals in the general Japanese population. A cross-sectional nationwide survey was undertaken in November 2007. Men and women were randomly selected from 300 districts throughout Japan. Data from 7671 (3532 men (average age 53.5 ± 17.0 years) and 4139 women (average age 53.9 ± 17.7 years)) were analyzed. Participants completed a self-reported questionnaire on stress, sleep disorders, and stress coping strategies in the previous month. Highly stressed individuals comprised 16.6% (95% confidence interval 15.8-17.5%) of the total sample, and most were aged 20-49 years. In multiple logistic regression, symptoms of insomnia (ie, difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening), excessive daytime sleepiness, nightmares, daytime malfunction, and lack of rest due to sleep deprivation were more prone to occur in highly stressed individuals. In addition, logistic regression analysis controlling for other adjustment factors revealed that stress coping strategies such as 'giving up on problem-solving', 'enduring problems patiently', 'smoking' and 'drinking alcohol' were positively associated with the above-mentioned sleep disorders. On the other hand, stress coping strategies such as 'exercising', 'enjoying hobbies', and 'sharing worries' were inversely associated with the above-mentioned sleep disorders. Distraction-based stress coping (eg, hobbies, exercise, and optimistic thinking) was found to be preferable to problem-based stress coping in a highly stressed Japanese general population. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Crash simulation of hybrid structures considering the stress and strain rate dependent material behavior of thermoplastic materials

    Science.gov (United States)

    Hopmann, Ch.; Schöngart, M.; Weber, M.; Klein, J.

    2015-05-01

    Thermoplastic materials are more and more used as a light weight replacement for metal, especially in the automotive industry. Since these materials do not provide the mechanical properties, which are required to manufacture supporting elements like an auto body or a cross bearer, plastics are combined with metals in so called hybrid structures. Normally, the plastics components are joined to the metal structures using different technologies like welding or screwing. Very often, the hybrid structures are made of flat metal parts, which are stiffened by a reinforcement structure made of thermoplastic materials. The loads on these structures are very often impulsive, for example in the crash situation of an automobile. Due to the large stiffness variation of metal and thermoplastic materials, complex states of stress and very high local strain rates occur in the contact zone under impact conditions. Since the mechanical behavior of thermoplastic materials is highly dependent on these types of load, the crash failure of metal plastic hybrid parts is very complex. The problem is that the normally used strain rate dependent elastic/plastic material models are not capable to simulate the mechanical behavior of thermoplastic materials depended on the state of stress. As part of a research project, a method to simulate the mechanical behavior of hybrid structures under impact conditions is developed at the IKV. For this purpose, a specimen for the measurement of mechanical properties dependet on the state of stress and a method for the strain rate depended characterization of thermoplastic materials were developed. In the second step impact testing is performed. A hybrid structure made from a metal sheet and a reinforcement structure of a Polybutylenterephthalat Polycarbonate blend is tested under impact conditions. The measured stress and strain rate depended material data are used to simulate the mechanical behavior of the hybrid structure under highly dynamic load with

  6. Ectopic expression of a horseradish peroxidase enhances growth rate and increases oxidative stress resistance in hybrid aspen.

    Science.gov (United States)

    Kawaoka, Akiyoshi; Matsunaga, Etsuko; Endo, Saori; Kondo, Shinkichi; Yoshida, Kazuya; Shinmyo, Atsuhiko; Ebinuma, Hiroyasu

    2003-07-01

    We previously demonstrated that overexpression of the horseradish (Armoracia rusticana) peroxidase prxC1a gene stimulated the growth rate of tobacco (Nicotiana tabacum) plants. Here, the cauliflower mosaic virus 35S::prxC1a construct was introduced into hybrid aspen (Populus sieboldii x Populus grandidentata). The growth rate of these transformed hybrid aspen plants was substantially increased under greenhouse conditions. The average stem length of transformed plants was 25% greater than that of control plants. There was no other obvious phenotypic difference between the transformed and control plants. Fast-growing transformed hybrid aspen showed high levels of expression of prxC1a and had elevated peroxidase activities toward guaiacol and ascorbate. However, there was no increase of the endogenous class I ascorbate peroxidase activities in the transformed plants by separate assay and activity staining of native polyacrylamide gel electrophoresis. Furthermore, calli derived from the transformed hybrid aspen grew faster than those from control plants and were resistant to the oxidative stress imposed by hydrogen peroxide. Therefore, enhanced peroxidase activity affects plant growth rate and oxidative stress resistance.

  7. Identification of single nucleotide polymorphisms (SNPs at candidate genes involved in abiotic stress in two Prosopis species of hybrids

    Directory of Open Access Journals (Sweden)

    Maria F. Pomponio

    2014-12-01

    Full Text Available Aim of the study: Identify and compare SNPs on candidate genes related to abiotic stress in Prosopis chilensis, Prosopis flexuosa and interspecific hybridsArea of the study: Chaco árido, Argentina. Material and Methods: Fragments from 6 candidate genes were sequenced in 60 genotypes. DNA polymorphisms were analyzed.Main Results: The analysis revealed that the hybrids had the highest rate of polymorphism, followed by P. flexuosa and P. chilensis, the values found are comparable to other forest tree species.Research highlights: This approach will help to study genetic diversity variation on natural populations for assessing the effects of environmental changes.Keywords: SNPs; abiotic stress; interspecific variation; molecular markers. 

  8. General self-efficacy and posttraumatic stress after a natural disaster: a longitudinal study.

    Science.gov (United States)

    Nygaard, Egil; Hussain, Ajmal; Siqveland, Johan; Heir, Trond

    2016-04-06

    Self-efficacy may be an important factor in individuals' recovery from posttraumatic stress reactions after a natural disaster. However, few longitudinal studies have investigated whether self-efficacy predicts the course of posttraumatic recovery beyond lower initial levels of distress. The purpose of the present study was to investigate whether general self-efficacy is related to recovery from posttraumatic stress reactions from a longitudinal perspective. A total of 617 Norwegians exposed to the 2004 Southeast Asian tsunami completed self-report questionnaires measuring their level of disaster exposure and general self-efficacy at 6 months and posttraumatic stress reactions 6 months and 2 years post-disaster. Predictors of changes in posttraumatic stress reactions were analyzed with multivariate mixed effects models. Self-efficacy at 6 months post-disaster was unrelated to trauma exposure and inversely related to posttraumatic stress reactions at 6 months and 2 years post-disaster. However, self-efficacy was not related to recovery from posttraumatic stress reactions between 6 months and 2 years post-disaster. In conclusion, general self-efficacy is related to lower levels of posttraumatic stress reactions in the first months after a disaster but does not appear to be related to improved recovery rates over the longer term.

  9. Arousal Predisposition as a Vulnerability Indicator for Psychosis: A General Population Online Stress Induction Study

    Directory of Open Access Journals (Sweden)

    Annika Clamor

    2015-01-01

    Full Text Available Explanatory models ascribe to arousability a central role for the development of psychotic symptoms. Thus, a disposition to hyperarousal (i.e., increased arousal predisposition (AP may serve as an underlying vulnerability indicator for psychosis by interacting with stressors to cause symptoms. In this case, AP, stress-response, and psychotic symptoms should be linked before the development of a diagnosable psychotic disorder. We conducted a cross-sectional online study in a population sample (N=104; Mage=27.7 years, SD=11.2, range 18–70. Participants rated their AP and subclinical psychotic symptoms. Participants reported their stress-levels before and after two stress inductions including an arithmetic and a social stressor. The participants with an increased AP generally felt more stressed. However, AP was not associated with the specific stress-response. As expected, positive psychotic symptoms were significantly associated with AP, but this was not mediated by general stress-levels. Its association to subtle, nonclinical psychotic symptoms supports our assumption that AP could be a vulnerability indicator for psychosis. The trait is easily accessible via a short self-report and could facilitate the identification of people at risk and be a promising target for early stress-management. Further research is needed to clarify its predictive value for stress-responses.

  10. Selection on crop-derived traits and QTL in sunflower (Helianthus annuus) crop-wild hybrids under water stress.

    Science.gov (United States)

    Owart, Birkin R; Corbi, Jonathan; Burke, John M; Dechaine, Jennifer M

    2014-01-01

    Locally relevant conditions, such as water stress in irrigated agricultural regions, should be considered when assessing the risk of crop allele introgression into wild populations following hybridization. Although research in cultivars has suggested that domestication traits may reduce fecundity under water stress as compared to wild-like phenotypes, this has not been investigated in crop-wild hybrids. In this study, we examine phenotypic selection acting on, as well as the genetic architecture of vegetative, reproductive, and physiological characteristics in an experimental population of sunflower crop-wild hybrids grown under wild-like low water conditions. Crop-derived petiole length and head diameter were favored in low and control water environments. The direction of selection differed between environments for leaf size and leaf pressure potential. Interestingly, the additive effect of the crop-derived allele was in the direction favored by selection for approximately half the QTL detected in the low water environment. Selection favoring crop-derived traits and alleles in the low water environment suggests that a subset of these alleles would be likely to spread into wild populations under water stress. Furthermore, differences in selection between environments support the view that risk assessments should be conducted under multiple locally relevant conditions.

  11. Selye's general adaptation syndrome: stress-induced gastro-duodenal ulceration and inflammatory bowel disease.

    Science.gov (United States)

    Fink, George

    2017-03-01

    Hans Selye in a note to Nature in 1936 initiated the field of stress research by showing that rats exposed to nocuous stimuli responded by way of a 'general adaptation syndrome' (GAS). One of the main features of the GAS was the 'formation of acute erosions in the digestive tract, particularly in the stomach, small intestine and appendix'. This provided experimental evidence for the view based on clinical data that gastro-duodenal (peptic) ulcers could be caused by stress. This hypothesis was challenged by Marshall and Warren's Nobel Prize (2005)-winning discovery of a causal association between Helicobacter pylori and peptic ulcers. However, clinical and experimental studies suggest that stress can cause peptic ulceration in the absence of H. pylori Predictably, the etiological pendulum of gastric and duodenal ulceration has swung from 'all stress' to 'all bacteria' followed by a sober realization that both factors play a role, separately as well as together. This raises the question as to whether stress and H. pylori interact, and if so, how? Stress has also been implicated in inflammatory bowel disease (IBD) and related disorders; however, there is no proof yet that stress is the primary etiological trigger for IBD. Central dopamine mechanisms seem to be involved in the stress induction of peptic ulceration, whereas activation of the sympathetic nervous system and central and peripheral corticotrophin-releasing factor appears to mediate stress-induced IBD. © 2017 Society for Endocrinology.

  12. Monotone Hybrid Projection Algorithms for an Infinitely Countable Family of Lipschitz Generalized Asymptotically Quasi-Nonexpansive Mappings

    Directory of Open Access Journals (Sweden)

    Watcharaporn Cholamjiak

    2009-01-01

    Full Text Available We prove a weak convergence theorem of the modified Mann iteration process for a uniformly Lipschitzian and generalized asymptotically quasi-nonexpansive mapping in a uniformly convex Banach space. We also introduce two kinds of new monotone hybrid methods and obtain strong convergence theorems for an infinitely countable family of uniformly Lipschitzian and generalized asymptotically quasi-nonexpansive mappings in a Hilbert space. The results improve and extend the corresponding ones announced by Kim and Xu (2006 and Nakajo and Takahashi (2003.

  13. Levels of Stress among General Practitioners, Students and Specialists In Pediatric Dentistry during Dental Treatment.

    Science.gov (United States)

    Davidovich, E; Pessov, Y; Baniel, A; Ram, D

    2015-01-01

    To assess self-reported stress during the performance of different procedures in pediatric dentistry, according to the professional experience of the dentists. During the years 2010 to 2011, an anonymous survey was administered by means of an internet link, and by distribution at professional meetings of dentists . No statistically significant differences in stress were reported for maxilla and mandibular procedures. Placement of a rubber dam was rated as the most stressful procedure among dental students. For general practitioners and specialists, injection of local anesthesia to an anxious child was the most stressful procedure, regardless of age, sex, or years of professional experience. A negative correlation was found between years of experience and level of stress for all the procedures surveyed, but not for the use of nitrous oxide. No differences were found between male and female dentists in stress scores for any of the procedures. Higher rates of stress during operative procedures were reported among dental students than among experienced dentists. Anxiety of the pediatric patients, but not the location of the procedure: maxillary or mandibular, affected the dentists' reported level of stress.

  14. Relationship Between Job Stress Among Nurses with Their General Health Status in Kamali Hospital in 1392

    Directory of Open Access Journals (Sweden)

    B. Mashak

    2015-11-01

    Full Text Available Background: In jobs where human contact is like nursing, more tension there. This destructive and multidimensional phenomenon can be increased absenteeism, reduced work efficiency and create energy and physical and mental illnesses lead to a decline in the quality of patient care. The purpose of this study was to investigate the relationship between stress and general health and help reduce the stress they are. Methods: This cross-sectional study on 78 public health nurses and Grft.prsshOsipow questionnaire included demographic information, job stress indicators (6 Stress workload involved, incompetence of duality role, scope, roles, responsibilities and physical environment and public health have been classified. Results: The findings show different aspects of occupational stress on 2/49% of the variation in the role and functions of stress, mild confusion, the burden of duties (45%, responsibility and physical environment (62%, stress higher. The aspects of public health, 48% of nurses in the physical symptoms (moderate and (63% of anxiety in the top 40 percent in the social dysfunction in Hdpayyn and 40% of the depression at the bottom were evaluated. Conclusion: The results of this study were determined and compared with previous studies in the same field  Create occupational stress can adversely affect the performance of nurses and public health they have.Implementing ways to reduce stress and burnout can promote mental health nurses to help improve the quality of nursing care.The results will help health systems to create a quiet working conditions largely reduce occupational stress.

  15. General hybrid projective complete dislocated synchronization with non-derivative and derivative coupling based on parameter identification in several chaotic and hyperchaotic systems

    International Nuclear Information System (INIS)

    Sun Jun-Wei; Shen Yi; Zhang Guo-Dong; Wang Yan-Feng; Cui Guang-Zhao

    2013-01-01

    According to the Lyapunov stability theorem, a new general hybrid projective complete dislocated synchronization scheme with non-derivative and derivative coupling based on parameter identification is proposed under the framework of drive-response systems. Every state variable of the response system equals the summation of the hybrid drive systems in the previous hybrid synchronization. However, every state variable of the drive system equals the summation of the hybrid response systems while evolving with time in our method. Complete synchronization, hybrid dislocated synchronization, projective synchronization, non-derivative and derivative coupling, and parameter identification are included as its special item. The Lorenz chaotic system, Rössler chaotic system, memristor chaotic oscillator system, and hyperchaotic Lü system are discussed to show the effectiveness of the proposed methods. (general)

  16. A Comparison of Stress and Burnout between Dutch General and Special Education Teachers

    NARCIS (Netherlands)

    J.C. van der Wolf; H.A. Everaert

    2006-01-01

    In this study self-reported stress and burn-out levels between general and special education teachers in the Netherlands are compared. More than eight hundred teachers were assessed with the Utrechtse Burnout Schaal (UBOS-L/MBI) to determine their levels of emotional exhaustion, depersonalization,

  17. Does Empathy Predict Instructional Assignment-Related Stress? A Study in Special and General Education Teachers

    Science.gov (United States)

    Platsidou, Maria; Agaliotis, Ioannis

    2017-01-01

    The role of empathy in the teaching profession has been vastly investigated in relation to its effect on students, but research on how teachers' empathy affects their own well-being at work is limited. This study investigated empathy and instructional assignment-related stress factors of primary school teachers serving in general or special…

  18. Coping with Secondary Traumatic Stress by General Duty Police Officers: Practical Implications

    Science.gov (United States)

    Conn, Stephanie M.; Butterfield, Lee D.

    2013-01-01

    This study used the Critical Incident Technique to examine the factors that helped, hindered, or might have helped 10 general duty police officers to cope with secondary traumatic stress. The data were best represented by 14 categories: self-care, family/significant other support, talking with co-workers, emotional engagement, work environment,…

  19. Generalized lower-hybrid drift instabilities in current-sheet equilibrium

    International Nuclear Information System (INIS)

    Yoon, Peter H.; Lui, Anthony T. Y.; Sitnov, Mikhail I.

    2002-01-01

    A class of drift instabilities in one-dimensional current-sheet configuration, i.e., classical Harris equilibrium, with frequency ranging from low ion-cyclotron to intermediate lower-hybrid frequencies, are investigated with an emphasis placed on perturbations propagating along the direction of cross-field current flow. Nonlocal two-fluid stability analysis is carried out, and a class of unstable modes with multiple eigenstates, similar to that of the familiar quantum mechanical potential-well problem, are found by numerical means. It is found that the most unstable modes correspond to quasi-electrostatic, short-wavelength perturbations in the lower-hybrid frequency range, with wave functions localized at the edge of the current sheet where the density gradient is maximum. It is also found that there exist quasi-electromagnetic modes located near the center of the current sheet where the current density is maximum, with both kink- and sausage-type polarizations. These modes are low-frequency, long-wavelength perturbations. It turns out that the current-driven modes are low-order eigensolutions while the lower-hybrid-type modes are higher-order states, and there are intermediate solutions between the two extreme cases. Attempts are made to interpret the available simulation results in light of the present eigenmode analysis

  20. Redefining reproductive dormancy in Drosophila as a general stress response to cold temperatures.

    Science.gov (United States)

    Lirakis, Manolis; Dolezal, Marlies; Schlötterer, Christian

    2018-04-09

    Organisms regularly encounter unfavorable conditions and the genetic adaptations facilitating survival have been of long-standing interest to evolutionary biologists. Winter is one particularly stressful condition for insects, during which they encounter low temperatures and scarcity of food. Despite dormancy being a well-studied adaptation to facilitate overwintering, there is still considerable controversy about the distribution of dormancy among natural populations and between species in Drosophila. The current definition of dormancy as developmental arrest of oogenesis at the previtellogenic stage (stage 7) distinguishes dormancy from general stress related block of oogenesis at early vitellogenic stages (stages 8 - 9). In an attempt to resolve this, we scrutinized reproductive dormancy in D. melanogaster and D. simulans. We show that dormancy shows the same hallmarks of arrest of oogenesis at stage 9, as described for other stressors and propose a new classification for dormancy. Applying this modified classification, we show that both species express dormancy in cosmopolitan and African populations, further supporting that dormancy uses an ancestral pathway induced by environmental stress. While we found significant differences between individuals and the two Drosophila species in their sensitivity to cold temperature stress, we also noted that extreme temperature stress (8 °C) resulted in very strong dormancy incidence, which strongly reduced the differences seen at less extreme temperatures. We conclude that dormancy in Drosophila should not be considered a special trait, but is better understood as a generic stress response occurring at low temperatures. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. From coherent to incoherent mismatched interfaces: A generalized continuum formulation of surface stresses

    Science.gov (United States)

    Dingreville, Rémi; Hallil, Abdelmalek; Berbenni, Stéphane

    2014-12-01

    The equilibrium of coherent and incoherent mismatched interfaces is reformulated in the context of continuum mechanics based on the Gibbs dividing surface concept. Two surface stresses are introduced: a coherent surface stress and an incoherent surface stress, as well as a transverse excess strain. The coherent surface stress and the transverse excess strain represent the thermodynamic driving forces of stretching the interface while the incoherent surface stress represents the driving force of stretching one crystal while holding the other fixed and thereby altering the structure of the interface. These three quantities fully characterize the elastic behavior of coherent and incoherent interfaces as a function of the in-plane strain, the transverse stress and the mismatch strain. The isotropic case is developed in detail and particular attention is paid to the case of interfacial thermo-elasticity. This exercise provides an insight on the physical significance of the interfacial elastic constants introduced in the formulation and illustrates the obvious coupling between the interface structure and its associated thermodynamics quantities. Finally, an example based on atomistic simulations of Cu/Cu2O interfaces is given to demonstrate the relevance of the generalized interfacial formulation and to emphasize the dependence of the interfacial thermodynamic quantities on the incoherency strain with an actual material system.

  2. Stress before extinction learning enhances and generalizes extinction memory in a predictive learning task.

    Science.gov (United States)

    Meir Drexler, Shira; Hamacher-Dang, Tanja C; Wolf, Oliver T

    2017-05-01

    In extinction learning, the individual learns that a previously acquired association (e.g. between a threat and its predictor) is no longer valid. This learning is the principle underlying many cognitive-behavioral psychotherapeutic treatments, e.g. 'exposure therapy'. However, extinction is often highly-context dependent, leading to renewal (relapse of extinguished conditioned response following context change). We have previously shown that post-extinction stress leads to a more context-dependent extinction memory in a predictive learning task. Yet as stress prior to learning can impair the integration of contextual cues, here we aim to create a more generalized extinction memory by inducing stress prior to extinction. Forty-nine men and women learned the associations between stimuli and outcomes in a predictive learning task (day 1), extinguished them shortly after an exposure to a stress/control condition (day 2), and were tested for renewal (day 3). No group differences were seen in acquisition and extinction learning, and a renewal effect was present in both groups. However, the groups differed in the strength and context-dependency of the extinction memory. Compared to the control group, the stress group showed an overall reduced recovery of responding to the extinguished stimuli, in particular in the acquisition context. These results, together with our previous findings, demonstrate that the effects of stress exposure on extinction memory depend on its timing. While post-extinction stress makes the memory more context-bound, pre-extinction stress strengthens its consolidation for the acquisition context as well, making it potentially more resistant to relapse. These results have implications for the use of glucocorticoids as extinction-enhancers in exposure therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Work related stress, burnout, job satisfaction and general health of nurses: A follow-up study.

    Science.gov (United States)

    Khamisa, Natasha; Peltzer, Karl; Ilic, Dragan; Oldenburg, Brian

    2016-12-01

    Nurses experience high levels of work related stress and burnout as well as low job satisfaction and poor general health owing to the nature of their work. This paper seeks to provide a better understanding of the nature of relationships between work related stress, burnout, job satisfaction and general health of nurses over one year. This study involved a longitudinal design. Two hundred and seventy seven nurses from four hospitals completed a follow up survey consisting of five questionnaires. Data were collected between 2013 and 2014. The data were analysed using generalized estimation equation analysis. Lack of support was associated with burnout, patient care was associated with job satisfaction and staff issues were associated with general health of nurses. Burnout is more strongly related to job satisfaction than general health. The findings of this study could inform evidence based policy and practice through interventions aimed at improving job satisfaction and reducing the impact of burnout on general health of nurses. © 2016 John Wiley & Sons Australia, Ltd.

  4. Biomarkers of general stress in mussels as common indicators for marine biomonitoring programmes in Europe: The ICON experience

    NARCIS (Netherlands)

    Martínez-Gómez, C.; Robinson, C.D.; Burgeot, T.; Gubbins, M.J.; Halldórsson, H.P.; Albentosa, M.; Bignell, J.P.; Hylland, K.; Vethaak, A.D.

    2017-01-01

    This study investigated whether general stress biomarkers in mussels can be applied as common first-tier biomarkers in regional biomonitoring programmes in the North Sea (including Iceland) and western Mediterranean Sea. Stress on Stress (SoS) and lysosomal membrane stability (LMS) biomarkers were

  5. Patient stress in intensive care: comparison between a coronary care unit and a general postoperative unit

    Science.gov (United States)

    Dias, Douglas de Sá; Resende, Mariane Vanessa; Diniz, Gisele do Carmo Leite Machado

    2015-01-01

    Objective To evaluate and compare stressors identified by patients of a coronary intensive care unit with those perceived by patients of a general postoperative intensive care unit. Methods This cross-sectional and descriptive study was conducted in the coronary intensive care and general postoperative intensive care units of a private hospital. In total, 60 patients participated in the study, 30 in each intensive care unit. The stressor scale was used in the intensive care units to identify the stressors. The mean score of each item of the scale was calculated followed by the total stress score. The differences between groups were considered significant when p < 0.05. Results The mean ages of patients were 55.63 ± 13.58 years in the coronary intensive care unit and 53.60 ± 17.47 years in the general postoperative intensive care unit. For patients in the coronary intensive care unit, the main stressors were “being in pain”, “being unable to fulfill family roles” and “being bored”. For patients in the general postoperative intensive care unit, the main stressors were “being in pain”, “being unable to fulfill family roles” and “not being able to communicate”. The mean total stress scores were 104.20 ± 30.95 in the coronary intensive care unit and 116.66 ± 23.72 (p = 0.085) in the general postoperative intensive care unit. When each stressor was compared separately, significant differences were noted only between three items. “Having nurses constantly doing things around your bed” was more stressful to the patients in the general postoperative intensive care unit than to those in the coronary intensive care unit (p = 0.013). Conversely, “hearing unfamiliar sounds and noises” and “hearing people talk about you” were the most stressful items for the patients in the coronary intensive care unit (p = 0.046 and 0.005, respectively). Conclusion The perception of major stressors and the total stress score were similar between patients

  6. Development of Generalized Correlation Equation for the Local Wall Shear Stress

    International Nuclear Information System (INIS)

    Jeon, Yu Mi; Park, Ju Hwan

    2010-06-01

    The pressure drop characteristics for a fuel channel are essential for the design and reliable operation of a nuclear reactor. Over several decades, analytical methods have been developed to predict the friction factor in the fuel bundle flows. In order to enhance the accuracy of prediction for the pressure drop in a rod bundle, the influences of a channel wall and the local shear stress distribution should be considered. Therefore, the correlation equation for a local wall shear stress distribution should be developed in order to secure an analytical solution for the friction factor of a rod bundle. For a side subchannel, which has the influence of the channel wall, the local wall shear stress distribution is dependent on the ratio of wall to diameter (W/D) as well as the ratio of pitch to diameter (P/D). In the case that W/D has the same value with P/D, the local shear stress distribution can be simply correlated with the function of angular position for each value of P/D. While in the case where W/D has a different value than P/D, the correlation equation should be developed for each case of P/D and W/D. Therefore, in the present study, the generalized correlation equation of the local wall shear stress distribution was developed for a side subchannel in the case where W/D has a different value than P/D. Consequently, the generalized correlation equation of a local wall shear stress distribution can be represented by the equivalent pitch to diameter ratio, P'/D for the case that P/D and W/D had a different value

  7. Professional stress in general practitioners and psychiatrists: The level of psycologic distress and burnout risk

    Directory of Open Access Journals (Sweden)

    Vićentić Sreten

    2010-01-01

    Full Text Available Background/Aim. So far, studies of stress have shown that physicians are at a high risk of sickness from psychic and somatic disorders related to professional stress, that can lead to important disturbance of personal, familiar and professional functionating. The aim of this study was to investigate the doctors exposition level to professional stress, to compare stress level in general practitioners (GP group with that in the group of psychiatrists and risk level for the apperance of burnout syndrome. Methods. This cross-section study included subjects recruited by a random sample method. Thirty General Practice doctors and 30 psychiatrists (totally 60 doctors filled the set of 3 questionnaires: Sociodemographics features, General Health Questionnaire (GHQ; Goldberg D, 1991, and Maslach Burnout Inventory (MBI; Maslach C, 1996. Appropriate statistical procedures (Pearson test, t-test, variance analysis in interpretation of the results were used. Results. A total level of psychic distress measured with the GHQ test in both groups of physicians was very low implying their good mental health. A difference in Burnout risk based on MBI test between the groups was statistically significant (χ2 = 4,286; p < 0.05 only at subscale Personal Accomplishment (MBI-PA; it was a consequence of a higher number of GPs with medium burnout risk (13.3 : 0.0%. However, even 35 physicians from the sample were affected with a high burnout risk measured with subscales Emotional Ehausation (MBI-EE and MBI-DP, showing that both groups of physicians had risk for the appearance of burnout syndrome. Conclusion. The obtained results showed a high burnout risk level in both, GPs and psychiatrists, groups. In both groups there was no presence of psychic disorders (anxiety, depression, insomnia, while there was a high level of emotional ehausation and overtension by job, and also a lower total personal accomplishment. Level of exposition to professional stress is higher in GPs

  8. Effect of personal and work stress on burnout, job satisfaction and general health of hospital nurses in South Africa

    Directory of Open Access Journals (Sweden)

    Natasha Khamisa

    2017-10-01

    Full Text Available The majority of studies to date have focused on the effects of work stress in the nursing environment, with the effect of personal stress in nursing being less explored. This study sought to determine whether personal stress is a more significant predictor of burnout, job satisfaction and general health than work stress. Of the 1200 nurses randomly selected to participate in the study, 895 agreed to complete six questionnaires over 3 weeks. Data was analysed using hierarchical multiple linear regression. Findings revealed that personal stress is a better predictor of burnout and general health than job satisfaction, which is better predicted by work stress. The findings of this study could inform potential solutions to reduce the impact of personal and work stress on burnout, job satisfaction and general health. Coping strategies and staffing strategies need to be evaluated within developing contexts such as South Africa to as certain their effectiveness.

  9. The Effect of Magnetic Field and Initial Stress on Fractional Order Generalized Thermoelastic Half-Space

    Directory of Open Access Journals (Sweden)

    Sunita Deswal

    2013-01-01

    Full Text Available The aim of this paper is to study magneto-thermoelastic interactions in an initially stressed isotropic homogeneous half-space in the context of fractional order theory of generalized thermoelasticity. State space formulation with the Laplace transform technique is used to obtain the general solution, and the resulting formulation is applied to the ramp type increase in thermal load and zero stress. Solutions of the problem in the physical domain are obtained by using a numerical method of the Laplace inverse transform based on the Fourier expansion technique, and the expressions for the displacement, temperature, and stress inside the half-space are obtained. Numerical computations are carried out for a particular material for illustrating the results. Results obtained for the field variables are displayed graphically. Some comparisons have been shown in figures to present the effect of fractional parameter, ramp parameter, magnetic field, and initial stress on the field variables. Some particular cases of special interest have been deduced from the present investigation.

  10. Mitochondrial Dysfunction Causes Oxidative Stress and Tapetal Apoptosis in Chemical Hybridization Reagent-Induced Male Sterility in Wheat

    Directory of Open Access Journals (Sweden)

    Shuping Wang

    2018-01-01

    Full Text Available Male sterility in plants has been strongly linked to mitochondrial dysfunction. Chemical hybridization agent (CHA-induced male sterility is an important tool in crop heterosis. Therefore, it is important to better understand the relationship between mitochondria and CHA-induced male sterility in wheat. This study reports on the impairment of mitochondrial function duo to CHA-SQ-1, which occurs by decreasing cytochrome oxidase and adenosine triphosphate synthase protein levels and theirs activities, respiratory rate, and in turn results in the inhibition of the mitochondrial electron transport chain (ETC, excessive production of reactive oxygen species (ROS and disruption of the alternative oxidase pathway. Subsequently, excessive ROS combined with MnSOD defects results in damage to the mitochondrial membrane, followed by ROS release into the cytoplasm. The microspores underwent severe oxidative stress during pollen development. Furthermore, chronic oxidative stress, together with the overexpression of type II metacaspase, triggered premature tapetal apoptosis, which resulted in pollen abortion. Accordingly, we propose a metabolic pathway for mitochondrial-mediated male sterility in wheat, which provides information on the molecular events underlying CHA-SQ-1-induced abortion of anthers and may serve as an additional guide to the practical application of hybrid breeding.

  11. Work Related Stress, Burnout, Job Satisfaction and General Health of Nurses

    Directory of Open Access Journals (Sweden)

    Natasha Khamisa

    2015-01-01

    Full Text Available Gaps in research focusing on work related stress, burnout, job satisfaction and general health of nurses is evident within developing contexts like South Africa. This study identified the relationship between work related stress, burnout, job satisfaction and general health of nurses. A total of 1200 nurses from four hospitals were invited to participate in this cross-sectional study (75% response rate. Participants completed five questionnaires and multiple linear regression analysis was used to determine significant relationships between variables. Staff issues are best associated with burnout as well as job satisfaction. Burnout explained the highest amount of variance in mental health of nurses. These are known to compromise productivity and performance, as well as affect the quality of patient care. Issues, such as security risks in the workplace, affect job satisfaction and health of nurses. Although this is more salient to developing contexts it is important in developing strategies and intervention programs towards improving nurse and patient related outcomes.

  12. Work Related Stress, Burnout, Job Satisfaction and General Health of Nurses

    Science.gov (United States)

    Khamisa, Natasha; Oldenburg, Brian; Peltzer, Karl; Ilic, Dragan

    2015-01-01

    Gaps in research focusing on work related stress, burnout, job satisfaction and general health of nurses is evident within developing contexts like South Africa. This study identified the relationship between work related stress, burnout, job satisfaction and general health of nurses. A total of 1200 nurses from four hospitals were invited to participate in this cross-sectional study (75% response rate). Participants completed five questionnaires and multiple linear regression analysis was used to determine significant relationships between variables. Staff issues are best associated with burnout as well as job satisfaction. Burnout explained the highest amount of variance in mental health of nurses. These are known to compromise productivity and performance, as well as affect the quality of patient care. Issues, such as security risks in the workplace, affect job satisfaction and health of nurses. Although this is more salient to developing contexts it is important in developing strategies and intervention programs towards improving nurse and patient related outcomes. PMID:25588157

  13. Work related stress, burnout, job satisfaction and general health of nurses.

    Science.gov (United States)

    Khamisa, Natasha; Oldenburg, Brian; Peltzer, Karl; Ilic, Dragan

    2015-01-12

    Gaps in research focusing on work related stress, burnout, job satisfaction and general health of nurses is evident within developing contexts like South Africa. This study identified the relationship between work related stress, burnout, job satisfaction and general health of nurses. A total of 1200 nurses from four hospitals were invited to participate in this cross-sectional study (75% response rate). Participants completed five questionnaires and multiple linear regression analysis was used to determine significant relationships between variables. Staff issues are best associated with burnout as well as job satisfaction. Burnout explained the highest amount of variance in mental health of nurses. These are known to compromise productivity and performance, as well as affect the quality of patient care. Issues, such as security risks in the workplace, affect job satisfaction and health of nurses. Although this is more salient to developing contexts it is important in developing strategies and intervention programs towards improving nurse and patient related outcomes.

  14. Abscisic acid, a stress hormone helps in improving water relations and yield of sunflower (helianthus annuus l.) hybrids under drought

    International Nuclear Information System (INIS)

    Hussain, S.; Saleem, M.F.; Cheema, M.A.; Ashraf, M.Y.; Haq, M.A.

    2010-01-01

    Genotypic variation in water relations under drought is an important index of studying drought tolerance of crops. Abscisic acid (ABA) application helped in mitigating drought stress by improving water relations and yield. Three sunflower hybrids viz., DK-4040 (tall stature), S-278 (medium stature) and SF-187 (short stature) were subjected to different irrigation and ABA application regimes i.e., four irrigations (25 days after sowing (DAS), at bud initiation, at flower initiation and at achene formation) and with no ABA spray, three irrigations (25 days after sowing, at flower initiation and at achene formation) and with no ABA spray, three irrigations (25 days after sowing, at flower initiation and at achene formation) and with ABA spray at bud initiation, three irrigations (25 days after sowing), at bud initiation and at achene formation) and with no ABA spray, three irrigations (25 days after sowing), at bud initiation and at achene formation) and with ABA spray at flower initiation. The experiment was laid out in randomized complete block design with split plot arrangement and had three replications. Exogenous application of ABA under drought at either stage (bud or flower initiation) was helpful in ameliorating drought stress by improving water relations and yield of sunflower hybrids; however response was better when ABA was applied under drought at bud initiation than at flower initiation stage. Sunflower hybrid DK- 4040 showed better enhancement of drought tolerance by exogenous application of ABA under drought than SF-187 and S-278 because it showed more improvement in water potential, osmotic potential, turgor pressure, relative leaf water contents and achene yield. (author)

  15. Development of generalized correlation equation for the local wall shear stress

    International Nuclear Information System (INIS)

    Jeon, Yu Mi; Bae, Jun Ho; Park, Joo Hwan

    2010-01-01

    The pressure drop characteristics for a fuel channel are essential for the design and reliable operation of a nuclear reactor. Over several decades, analytical methods have been developed to predict the friction factor in the fuel bundle flows. In order to enhance the accuracy of prediction for the pressure drop in a rod bundle, the influences of a channel wall and the local shear stress distribution should be considered. Hence, the correlation equation for a local shear stress distribution should be developed in order to secure an analytical solution for the friction factor of a rod bundle. For a side subchannel, which has the influence of the channel wall, the local shear stress distribution is dependent on the ratio of wall to diameter (W/D) as well as the ratio of pitch to diameter (P/D). In the case that W/D has the same value with P/D, the local shear stress distribution can be simply correlated with the function of angular position for each value of P/D. While, in the case that W/D has the different value with P/D, the correlation equation should be developed for each case of P/D and W/D. Hence, in the present study, the generalized correlation equation of a local shear stress distribution is developed for a side subchannel in the case that W/D has the different value with P/D

  16. Intercomparison of the seasonal cycle of tropical surface stress in 17 AMIP atmospheric general circulation models

    Energy Technology Data Exchange (ETDEWEB)

    Saji, N.H.; Goswami, B.N. [Indian Inst. of Sci., Bangalore (India). Centre for Atmos. and Oceanic Sci.

    1997-08-01

    The mean state of the tropical atmosphere is important as the nature of the coupling between the ocean and the atmosphere depends nonlinearly on the basic state of the coupled system. The simulation of the annual cycle of the tropical surface wind stress by 17 atmospheric general circulation models (AGCMs) is examined and intercompared. The models considered were part of the atmospheric model intercomparison project (AMIP) and were integrated with observed sea surface temperature (SST) for the decade 1979-1988. Several measures have been devised to intercompare the performance of the 17 models on global tropical as well as regional scales. Within the limits of observational uncertainties, the models under examination simulate realistic tropical area-averaged zonal and meridional annual mean stresses. This is a noteworthy improvement over older generation low resolution models which were noted for their simulation of surface stresses considerably weaker than the observations. The models also simulate realistic magnitudes of the spatial distribution of the annual mean surface stress field and are seen to reproduce realistically its observed spatial pattern. Similar features are observed in the simulations of the annual variance field. The models perform well over almost all the tropical regions apart from a few. Of these, the simulations over Somali are interesting. Over this region, the models are seen to underestimate the annual mean zonal and meridional stresses. There is also wide variance between the different models in simulating these quantities. 44 refs.

  17. High workload and job stress are associated with lower practice performance in general practice: an observational study in 239 general practices in the Netherlands.

    NARCIS (Netherlands)

    Hombergh, P. van den; Kunzi, B.; Elwyn, G.; Doremalen, J.H.M. van; Akkermans, R.P.; Grol, R.P.T.M.; Wensing, M.J.P.

    2009-01-01

    BACKGROUND: The impact of high physician workload and job stress on quality and outcomes of healthcare delivery is not clear. Our study explored whether high workload and job stress were associated with lower performance in general practices in the Netherlands. METHODS: Secondary analysis of data

  18. Examining nicotine craving during abstinence among adolescent smokers: the roles of general perceived stress and temptation-coping strategies

    NARCIS (Netherlands)

    Kleinjan, M.; Visser, A.F.; Engels, R.C.M.E.

    2012-01-01

    The present study examined the effects of general perceived stress and temptation-coping strategies on the occurrence of nicotine craving among 125 daily-smoking adolescents. General perceived stress was measured at baseline. Craving was assessed at baseline and directly after a 24-hour period of

  19. Generalized stress field in granular soils heap with Rayleigh–Ritz method

    Directory of Open Access Journals (Sweden)

    Gang Bi

    2017-02-01

    Full Text Available The stress field in granular soils heap (including piled coal will have a non-negligible impact on the settlement of the underlying soils. It is usually obtained by measurements and numerical simulations. Because the former method is not reliable as pressure cells instrumented on the interface between piled coal and the underlying soft soil do not work well, results from numerical methods alone are necessary to be doubly checked with one more method before they are extended to more complex cases. The generalized stress field in granular soils heap is analyzed with Rayleigh–Ritz method. The problem is divided into two cases: case A without horizontal constraint on the base and case B with horizontal constraint on the base. In both cases, the displacement functions u(x, y and v(x, y are assumed to be cubic polynomials with 12 undetermined parameters, which will satisfy the Cauchy's partial differential equations, generalized Hooke's law and boundary equations. A function is built with the Rayleigh–Ritz method according to the principle of minimum potential energy, and the problem is converted into solving two undetermined parameters through the variation of the function, while the other parameters are expressed in terms of these two parameters. By comparison of results from the Rayleigh–Ritz method and numerical simulations, it is demonstrated that the Rayleigh–Ritz method is feasible to study the generalized stress field in granular soils heap. Solutions from numerical methods are verified before being extended to more complicated cases.

  20. [Effects of exogenous silicon on the pollination and fertility characteristics of hybrid rice under heat stress during anthesis].

    Science.gov (United States)

    Wu, Chen-Yang; Chen, Dan; Luo, Hai-Wei; Yao, Yi-min; Wang, Zhi-Wei; Tsutomu, Matsui; Tian, Xiao-Hai

    2013-11-01

    Taking two medium-maturing indica rice hybrids Jinyou 63 and Shanyou 63 as test materials, this paper studied the effects of applying silicon fertilizer on the flag leaf chlorophyll content, photosynthetic properties, antioxidant enzyme activities, malondialdehyde (MDA) content, pollen vigor, anther acid invertase activity, pollination, and seed-setting of hybrid rice under the heat stress during anthesis. This study was conducted in pots and under growth chamber. Soluble solution of silicon fertilizer applied as Na2SiO3 x 9H2O was sprayed on the growing plants after early jointing stage, with three times successively and at an interval of one week. The pots were then moved into growth chamber to subject to normal temperature vs. high temperature (termed as heat stress) for five days. In treatment normal temperature, the average daily temperature was set at 26.6 degrees C, and the maximum daily temperature was set at 29.4 degres C; in treatment high temperature, the average and the maximum daily temperature were set at 33.2 degrees C and 40.1 degrees C, respectively. As compared with the control, applying silicon increased the flag leaf chlorophyll content significantly, improved the net photosynthetic rate and stomatal conductance, decreased the accumulative inter- cellular CO2 concentration, improved the leaf photosynthesis, reduced the MDA content, and improved the activities of SOD, POD and CAT under heat stress. In addition, applying silicon improved the anther acid invertase activity and the pollen vigor, increased the anther basal dehiscence width, total number of pollination per stigma, germinated number, germination rate of pollen, and percentage of florets with more than 10 germinated pollen grains, decreased the percentage of florets with fewer than 20 germinated pollen grains, and thus, alleviated the fertility loss of Jinyou 63 and Shanyou 63 under heat stress by 13.4% and 14.1%, respectively. It was suggested that spraying exogenous silicon in the

  1. Identification of water stress genes in Pinus pinaster Ait. by controlled progressive stress and suppression-subtractive hybridization.

    Science.gov (United States)

    Perdiguero, Pedro; Collada, Carmen; Barbero, María Del Carmen; García Casado, Gloria; Cervera, María Teresa; Soto, Alvaro

    2012-01-01

    Climate change is a major challenge particularly for forest tree species, which will have to face the severe alterations of environmental conditions with their current genetic pool. Thus, an understanding of their adaptive responses is of the utmost interest. In this work we have selected Pinus pinaster as a model species. This pine is one of the most important conifers (for which molecular tools and knowledge are far more scarce than for angiosperms) in the Mediterranean Basin, which is characterised in all foreseen scenarios as one of the regions most drastically affected by climate change, mainly because of increasing temperature and, particularly, by increasing drought. We have induced a controlled, increasing water stress by adding PEG to a hydroponic culture. We have generated a subtractive library, with the aim of identifying the genes induced by this stress and have searched for the most reliable expressional candidate genes, based on their overexpression during water stress, as revealed by microarray analysis and confirmed by RT-PCR. We have selected a set of 67 candidate genes belonging to different functional groups that will be useful molecular tools for further studies on drought stress responses, adaptation, and population genomics in conifers, as well as in breeding programs. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  2. Tools for Brain-Computer Interaction: a general concept for a hybrid BCI (hBCI

    Directory of Open Access Journals (Sweden)

    Gernot R. Mueller-Putz

    2011-11-01

    Full Text Available The aim of this work is to present the development of a hybrid Brain-Computer Interface (hBCI which combines existing input devices with a BCI. Thereby, the BCI should be available if the user wishes to extend the types of inputs available to an assistive technology system, but the user can also choose not to use the BCI at all; the BCI is active in the background. The hBCI might decide on the one hand which input channel(s offer the most reliable signal(s and switch between input channels to improve information transfer rate, usability, or other factors, or on the other hand fuse various input channels. One major goal therefore is to bring the BCI technology to a level where it can be used in a maximum number of scenarios in a simple way. To achieve this, it is of great importance that the hBCI is able to operate reliably for long periods, recognizing and adapting to changes as it does so. This goal is only possible if many different subsystems in the hBCI can work together. Since one research institute alone cannot provide such different functionality, collaboration between institutes is necessary. To allow for such a collaboration, a common software framework was investigated.

  3. Nurse prescribing in general practice: a qualitative study of job satisfaction and work-related stress.

    Science.gov (United States)

    Cousins, Rosanna; Donnell, Christine

    2012-04-01

    Studies examining the impact nurse prescribing have largely focused on the efficacy of the service. It was suggested in pro-prescribing policy arguments that extending the nursing role to include prescribing would increase job satisfaction. This assertion has not been fully explored. To investigate the impact of independent prescribing for experienced nurse practitioners (NPs) working in general practice. In-depth interviews were conducted with six NPs who each had at least 3 years experience of independent prescribing in a busy inner city general practice. Analysis of interview data yielded two main themes: as independent prescribers NPs experienced increased levels of both job satisfaction and work-related stress. Increased satisfaction was associated with having greater autonomy and being able to provide more holistic care. Increased work-related stress emerged from greater job demands, perceived insufficient support and perceived effort-reward imbalance that centred upon the enhanced role not being recognized in terms of an increase in grade and pay. Independent prescribing increases job satisfaction for NPs in general practice, but there is also evidence of stressors associated with the role. It is important that NPs in general practice are encouraged and supported towards providing the effective patient-centred care in the community envisaged by current UK government. We acknowledge that the results presented in this paper are based on a sample limited to one city; however, it provides information that has important implications for the well being of NPs and ultimately patient care.

  4. Quantum, classical, and hybrid QM/MM calculations in solution: General implementation of the ddCOSMO linear scaling strategy

    International Nuclear Information System (INIS)

    Lipparini, Filippo; Scalmani, Giovanni; Frisch, Michael J.; Lagardère, Louis; Stamm, Benjamin; Cancès, Eric; Maday, Yvon; Piquemal, Jean-Philip; Mennucci, Benedetta

    2014-01-01

    We present the general theory and implementation of the Conductor-like Screening Model according to the recently developed ddCOSMO paradigm. The various quantities needed to apply ddCOSMO at different levels of theory, including quantum mechanical descriptions, are discussed in detail, with a particular focus on how to compute the integrals needed to evaluate the ddCOSMO solvation energy and its derivatives. The overall computational cost of a ddCOSMO computation is then analyzed and decomposed in the various steps: the different relative weights of such contributions are then discussed for both ddCOSMO and the fastest available alternative discretization to the COSMO equations. Finally, the scaling of the cost of the various steps with respect to the size of the solute is analyzed and discussed, showing how ddCOSMO opens significantly new possibilities when cheap or hybrid molecular mechanics/quantum mechanics methods are used to describe the solute

  5. Quantum, classical, and hybrid QM/MM calculations in solution: General implementation of the ddCOSMO linear scaling strategy

    Energy Technology Data Exchange (ETDEWEB)

    Lipparini, Filippo, E-mail: flippari@uni-mainz.de [Sorbonne Universités, UPMC Univ. Paris 06, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005 Paris (France); Sorbonne Universités, UPMC Univ. Paris 06, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris (France); Sorbonne Universités, UPMC Univ. Paris 06, Institut du Calcul et de la Simulation, F-75005 Paris (France); Scalmani, Giovanni; Frisch, Michael J. [Gaussian, Inc., 340 Quinnipiac St. Bldg. 40, Wallingford, Connecticut 06492 (United States); Lagardère, Louis [Sorbonne Universités, UPMC Univ. Paris 06, Institut du Calcul et de la Simulation, F-75005 Paris (France); Stamm, Benjamin [Sorbonne Universités, UPMC Univ. Paris 06, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005 Paris (France); CNRS, UMR 7598 and 7616, F-75005 Paris (France); Cancès, Eric [Université Paris-Est, CERMICS, Ecole des Ponts and INRIA, 6 and 8 avenue Blaise Pascal, 77455 Marne-la-Vallée Cedex 2 (France); Maday, Yvon [Sorbonne Universités, UPMC Univ. Paris 06, UMR 7598, Laboratoire Jacques-Louis Lions, F-75005 Paris (France); Institut Universitaire de France, Paris, France and Division of Applied Maths, Brown University, Providence, Rhode Island 02912 (United States); Piquemal, Jean-Philip [Sorbonne Universités, UPMC Univ. Paris 06, UMR 7616, Laboratoire de Chimie Théorique, F-75005 Paris (France); CNRS, UMR 7598 and 7616, F-75005 Paris (France); Mennucci, Benedetta [Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Risorgimento 35, 56126 Pisa (Italy)

    2014-11-14

    We present the general theory and implementation of the Conductor-like Screening Model according to the recently developed ddCOSMO paradigm. The various quantities needed to apply ddCOSMO at different levels of theory, including quantum mechanical descriptions, are discussed in detail, with a particular focus on how to compute the integrals needed to evaluate the ddCOSMO solvation energy and its derivatives. The overall computational cost of a ddCOSMO computation is then analyzed and decomposed in the various steps: the different relative weights of such contributions are then discussed for both ddCOSMO and the fastest available alternative discretization to the COSMO equations. Finally, the scaling of the cost of the various steps with respect to the size of the solute is analyzed and discussed, showing how ddCOSMO opens significantly new possibilities when cheap or hybrid molecular mechanics/quantum mechanics methods are used to describe the solute.

  6. Investigation of marital satisfaction and its relationship with job stress and general health of nurses in Qazvin, Iran

    OpenAIRE

    Azimian, Jalil; Piran, Pegah; Jahanihashemi, Hassan; Dehghankar, Leila

    2017-01-01

    Background Pressures in nursing can affect family life and marital problems, disrupt common social problems, increase work-family conflicts and endanger people?s general health. Aim To determine marital satisfaction and its relationship with job stress and general health of nurses. Methods This descriptive and cross-sectional study was done in 2015 in medical educational centers of Qazvin by using an ENRICH marital satisfaction scale and General Health and Job Stress questionnaires completed ...

  7. Effects of natural hybrid and non-hybrid Epichloë endophytes on the response of Hordelymus europaeus to drought stress.

    Science.gov (United States)

    Oberhofer, Martina; Güsewell, Sabine; Leuchtmann, Adrian

    2014-01-01

    Interspecific hybrid endophytes of the genus Epichloë (Ascomycota, Clavicipitaceae) are prevalent in wild grass populations, possibly because of their larger gene variation, resulting in increased fitness benefits for host plants; however, the reasons are not yet known. We tested hypotheses regarding niche expansion mediated by hybrid endophytes, population-dependent interactions and local co-adaptation in the woodland grass Hordelymus europaeus, which naturally hosts both hybrid and non-hybrid endophyte taxa. Seedlings derived from seeds of four grass populations made endophyte free were re-inoculated with hybrid or non-hybrid endophyte strains, or left endophyte free. Plants were grown in the glasshouse with or without drought treatment. Endophyte infection increased plant biomass and tiller production by 10-15% in both treatments. Endophyte types had similar effects on growth, but opposite effects on reproduction: non-hybrid endophytes increased seed production, whereas hybrid endophytes reduced or prevented it completely. The results are consistent with the observation that non-hybrid endophytes in H. europaeus prevail at dry sites, but cannot explain the prevalence of hybrid endophytes. Thus, our results do not support the hypothesis of niche expansion of hybrid-infected plants. Moreover, plants inoculated with native relative to foreign endophytes yielded higher infections, but both showed similar growth and survival, suggesting weak co-adaptation. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  8. Optimal Constant-Stress Accelerated Degradation Test Plans Using Nonlinear Generalized Wiener Process

    Directory of Open Access Journals (Sweden)

    Zhen Chen

    2016-01-01

    Full Text Available Accelerated degradation test (ADT has been widely used to assess highly reliable products’ lifetime. To conduct an ADT, an appropriate degradation model and test plan should be determined in advance. Although many historical studies have proposed quite a few models, there is still room for improvement. Hence we propose a Nonlinear Generalized Wiener Process (NGWP model with consideration of the effects of stress level, product-to-product variability, and measurement errors for a higher estimation accuracy and a wider range of use. Then under the constraints of sample size, test duration, and test cost, the plans of constant-stress ADT (CSADT with multiple stress levels based on the NGWP are designed by minimizing the asymptotic variance of the reliability estimation of the products under normal operation conditions. An optimization algorithm is developed to determine the optimal stress levels, the number of units allocated to each level, inspection frequency, and measurement times simultaneously. In addition, a comparison based on degradation data of LEDs is made to show better goodness-of-fit of the NGWP than that of other models. Finally, optimal two-level and three-level CSADT plans under various constraints and a detailed sensitivity analysis are demonstrated through examples in this paper.

  9. A definition and evaluation procedure of generalized stress intensity factors at cracks and multi-material wedges

    International Nuclear Information System (INIS)

    Song Chongmin

    2010-01-01

    A definition of generalized stress intensity factors is proposed. It is based on a matrix function solution for singular stress fields obtained from the scaled boundary finite-element method. The dimensions of the matrix are equal to the number of singular terms. Not only real and complex power singularities but also power-logarithmic singularities are represented in a unified expression without explicitly determining the type of singularity. The generalized stress intensity factors are evaluated directly from the definition by following standard stress recovery procedures in the finite element method. Numerical examples are presented to valid the definition and evaluation procedure.

  10. Psycho-social stress, insomnia and temazepam: a sleep laboratory evaluation in a "general practice" sample.

    Science.gov (United States)

    Beary, M D; Lacey, J H; Crutchfield, M B; Bhat, A V

    1984-01-01

    Taking a population of women most of whom were about to seek medication from their general practitioner for stress-induced insomnia, this sleep laboratory study examined--both electro -physiologically and psychologically--the immediate impact of temazepam, at normal prescribed dosage, on sleep. The study was double-blind, controlled with random allocation. Temazepam 20 mg, prepared as a liquid in a soft gelatin capsule, reduced sleep latency and prolonged total sleep time. A reduction in stage shifts to Stages I and II and a reduction in time spent in Stages 0 + I suggest more restful sleep. The sleep "architecture" (including REM/NREM cycling, total SWS and REM time) was relatively undisturbed. Temazepam would seem to be effective as a first-line hypnotic for short-term use in stressed patients.

  11. Stress sensitivity and resilience in the chronic mild stress rat model of depression; an in situ hybridization study

    DEFF Research Database (Denmark)

    Bergström, A; Jayatissa, M N; Mørk, A

    2008-01-01

    in stress. Moreover, in the CA3 we found downregulation of vascular endothelial growth factor (VEGF) mRNA in the CMS sensitive group. Downregulation of VEGF suggests impaired hippocampal function, caused by loss of trophic factor neuroprotective support, as part of a previously uncharacterized mechanism...... for development of anhedonia. CMS induced anhedonia was not related to mRNA expression differences of the dopamine receptors D(1) and D(2), enkephalin, dynorphin, the NMDA receptor subtype NR2B in the ventral striatum, BDNF expression in the dentate gyrus, nor corticotrophin releasing hormone (CRH) and arginine...

  12. Stress induced birefringence in hybrid TIR/PBG guiding solid photonic crystal fibers

    DEFF Research Database (Denmark)

    Lyngsøe, Jens Kristian; Mangan, Brian Joseph; Olausson, Christina Bjarnal Thulin

    2010-01-01

    We report on two types of polarization maintaining solid photonic crystal fibers that guide light by a combination of a photonic bandgap and total internal reflection. Group and phase birefringence are studied experimentally and numerically for stress-applying parts made from B-doped and F......-doped silica. The stress field originating from Ge-doped cladding rods is shown to interfere with the stress field from the B-doped and F-doped rods. Since the differential expansion coefficients of B-doped and F-doped silica have opposite signs this interference is either destructive or constructive....... Consequently, we found that the fiber with F-doped stress applying parts has the highest modal phase birefringence, and polarization cross talk is characterized by an h-parameter below 3⋅10−5 m−1....

  13. What Differentiates Employees' Job Performance Under Stressful Situations: The Role of General Self-Efficacy.

    Science.gov (United States)

    Lu, Chang-Qin; Du, Dan-Yang; Xu, Xiao-Min

    2016-10-02

    The aim of this research is to verify the two-dimensional challenge-hindrance stressor framework in the Chinese context, and investigate the moderating effect of general self-efficacy in the stress process. Data were collected from 164 Chinese employee-supervisor dyads. The results demonstrated that challenge stressors were positively related to job performance while hindrance stressors were negatively related to job performance. Furthermore, general self-efficacy strengthened the positive relationship between challenge stressors and job performance, whereas the attenuating effect of general self-efficacy on the negative relationship between hindrance stressors and job performance was nonsignificant. These findings qualify the two-dimensional challenge-hindrance stressor framework, and support the notion that employees with high self-efficacy benefit more from the positive effect of challenge stressors in the workplace. By investigating the role of an individual difference variable in the challenge-hindrance stressor framework, this research provides a more accurate picture of the nature of job stress, and enhances our understanding of the job stressor-job performance relationship.

  14. Differential accumulation of dehydrins in response to water stress for hybrid and common bermudagrass genotypes differing in drought tolerance.

    Science.gov (United States)

    Hu, Longxing; Wang, Zhaolong; Du, Hongmei; Huang, Bingru

    2010-01-15

    Expression of dehydrin proteins may be induced or enhanced by environmental stresses that lead to cell dehydration. The objective of the this study was to investigate genetic variation in dehydrin protein accumulation in response to drought stress of whole-plants or dehydration of detached leaves and to identify dehydrins differentially expressed in bermudagrass (Cynodon spp.) genotypes differing in drought tolerance. Plants of four hybrid bermudagrass (Cynodondactylon L. xCynodontransvaalensis L.) ('Tifway', 'Tifdwarf', 'Tifeagle', 'Kan1') and four common bermudagrass (Cynodon dactylon) ('C299', 'Sportbermuda', 'H10', and 'H19') genotypes were subjected to 14d of drought stress and detached leaves of two genotypes were exposed to dehydration in growth chambers. Turf quality and leaf relative water content (RWC) decreased while electrolyte leakage (EL) increased during whole-plant drought stress for all genotypes, with more pronounced changes in each parameter for 'C299' and 'Tifeagle' than those for other genotypes ('Tifway', 'Kan 1', 'Sportbermuda', 'H10', and H19'), suggesting that the former two genotypes were more sensitive to drought stress than the other genotypes. During dehydration of detached leaves, relative water loss rate (RWL) was significantly lower in drought-tolerant 'Tifway' than in drought-sensitive 'C299'. Immunoblotting analysis indicated that no dehydrin polypeptides were detected in all genotypes under well-watered conditions. A 24-kDa polypeptide was detected in 'C299' at 6 d of drought, but not in the other genotypes. The dehydrin polypeptides of about 14-74kDa accumulated at 10d of drought stress and in a range of RWL for detached leaves, and two dehydrins (31 and 40kDa) exhibited differential accumulation in the drought-sensitive 'C299' and tolerant 'Tifway', as demonstrated by the whole-plant drought responses. The 31-kDa dehydrin polypeptide was present only in 'Tifway' and 'H19' at 10d of drought stress, and accumulated with the

  15. Different perceptions of stress, coping styles, and general well-being among pregnant Chinese women: a structural equation modeling approach.

    Science.gov (United States)

    Lau, Ying; Tha, Pyai Htun; Wong, Daniel Fu Keung; Wang, Yuqiong; Wang, Ying; Yobas, Piyanee Klainin

    2016-02-01

    Few studies have examined different perceptions of stress or explored the positive aspects of well-being among pregnant Chinese women, so there is a need to explore these phenomena in order to fill the research gap. The aim of this study was to examine the relationships among the different perceptions of stress, coping styles, and general well-being using a structural equation modeling approach. We examined a hypothetical model among 755 pregnant Chinese women based on the integration of theoretical models. The Perceived Stress Scale (PSS), the Trait Coping Styles Questionnaire (TCSQ), and the General Well-Being Schedule (GWB) were used to measure perceived stress, coping styles, and general well-being, respectively. A structural equation model showed that positive and negative perceptions of stress significantly influenced positive and negative coping styles, respectively. Different perceptions of stress were significantly associated with general well-being, but different coping styles had no significant effects on general well-being. The model had a good fit to the data (IFI = 0.910, TLI = 0.904, CFI = 0.910, and RMSEA = 0.038). Different perception of stress was able to predict significant differences in coping styles and general well-being.

  16. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands

    NARCIS (Netherlands)

    Harmsen, R; Helms-Lorenz, M.; Maulana, R; van Veen, K; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the

  17. Numerical solution to generalized Burgers'-Fisher equation using Exp-function method hybridized with heuristic computation.

    Directory of Open Access Journals (Sweden)

    Suheel Abdullah Malik

    Full Text Available In this paper, a new heuristic scheme for the approximate solution of the generalized Burgers'-Fisher equation is proposed. The scheme is based on the hybridization of Exp-function method with nature inspired algorithm. The given nonlinear partial differential equation (NPDE through substitution is converted into a nonlinear ordinary differential equation (NODE. The travelling wave solution is approximated by the Exp-function method with unknown parameters. The unknown parameters are estimated by transforming the NODE into an equivalent global error minimization problem by using a fitness function. The popular genetic algorithm (GA is used to solve the minimization problem, and to achieve the unknown parameters. The proposed scheme is successfully implemented to solve the generalized Burgers'-Fisher equation. The comparison of numerical results with the exact solutions, and the solutions obtained using some traditional methods, including adomian decomposition method (ADM, homotopy perturbation method (HPM, and optimal homotopy asymptotic method (OHAM, show that the suggested scheme is fairly accurate and viable for solving such problems.

  18. Numerical solution to generalized Burgers'-Fisher equation using Exp-function method hybridized with heuristic computation.

    Science.gov (United States)

    Malik, Suheel Abdullah; Qureshi, Ijaz Mansoor; Amir, Muhammad; Malik, Aqdas Naveed; Haq, Ihsanul

    2015-01-01

    In this paper, a new heuristic scheme for the approximate solution of the generalized Burgers'-Fisher equation is proposed. The scheme is based on the hybridization of Exp-function method with nature inspired algorithm. The given nonlinear partial differential equation (NPDE) through substitution is converted into a nonlinear ordinary differential equation (NODE). The travelling wave solution is approximated by the Exp-function method with unknown parameters. The unknown parameters are estimated by transforming the NODE into an equivalent global error minimization problem by using a fitness function. The popular genetic algorithm (GA) is used to solve the minimization problem, and to achieve the unknown parameters. The proposed scheme is successfully implemented to solve the generalized Burgers'-Fisher equation. The comparison of numerical results with the exact solutions, and the solutions obtained using some traditional methods, including adomian decomposition method (ADM), homotopy perturbation method (HPM), and optimal homotopy asymptotic method (OHAM), show that the suggested scheme is fairly accurate and viable for solving such problems.

  19. Optimization and Static Stress Analysis of Hybrid Fiber Reinforced Composite Leaf Spring

    Directory of Open Access Journals (Sweden)

    Luay Muhammed Ali Ismaeel

    2015-01-01

    Full Text Available A monofiber reinforced composite leaf spring is proposed as an alternative to the typical steel one as it is characterized by high strength-to-weight ratio. Different reinforcing schemes are suggested to fabricate the leaf spring. The composite and the typical steel leaf springs are subjected to the same working conditions. A weight saving of about more than 60% can be achieved while maintaining the strength for the structures under consideration. The objective of the present study was to replace material for leaf spring. This study suggests various materials of hybrid fiber reinforced plastics (HFRP. Also the effects of shear moduli of the fibers, matrices, and the composites on the composites performance and responses are discussed. The results and behaviors of each are compared with each other and verified by comparison with analytical solution; a good convergence is found between them. The elastic properties of the hybrid composites are calculated using rules of mixtures and Halpin-Tsi equation through the software of MATLAB v-7. The problem is also analyzed by the technique of finite element analysis (FEA through the software of ANSYS v-14. An element modeling was done for every leaf with eight-node 3D brick element (SOLID185 3D 8-Node Structural Solid.

  20. Comparative proteome analysis of drought-sensitive and drought-tolerant rapeseed roots and their hybrid F1 line under drought stress.

    Science.gov (United States)

    Mohammadi, Payam Pour; Moieni, Ahmad; Komatsu, Setsuko

    2012-11-01

    Rapeseed (Brassica napus L.), which is the third leading source of vegetable oil, is sensitive to drought stress during the early vegetative growth stage. To investigate the initial response of rapeseed to drought stress, changes in the protein expression profiles of drought-sensitive (RGS-003) and drought-tolerant lines (SLM-003), and their F1 hybrid, were analyzed using a proteomics approach. Seven-day-old rapeseed seedlings were treated with drought stress by restricting water for 7 days, and proteins were extracted from roots and separated by two-dimensional polyacrylamide gel electrophoresis. In the sensitive rapeseed line, 35 protein spots were differentially expressed under drought stress, and proteins related to metabolism, energy, disease/defense, and transport were decreased. In the tolerant line, 32 protein spots were differentially expressed under drought stress, and proteins involved in metabolism, disease/defense, and transport were increased, while energy-related proteins were decreased. Six protein spots in F1 hybrid were common among expressed proteins in the drought-sensitive and -tolerant lines. Notably, tubulin beta-2 and heat shock protein 70 were decreased in the drought-sensitive line and hybrid F1 plants, while jasmonate-inducible protein and 20S proteasome subunit PAF1 were increased in the F1 hybrids and drought-tolerant line. These results indicate that (1) V-type H(+) ATPase, plasma-membrane associated cation-binding protein, HSP 90, and elongation factor EF-2 have a role in the drought tolerance of rapeseed; (2) The decreased levels of heat shock protein 70 and tubulin beta-2 in the drought-sensitive and hybrid F1 lines might explain the reduced growth of these lines in drought conditions.

  1. Investigating the effect of work stress, general health quality, organizational intelligence and job satisfaction on employee performance

    Directory of Open Access Journals (Sweden)

    Masoud Samadzadeh

    2013-12-01

    Full Text Available During the past few years, there have been tremendous efforts on measuring the effects of different factors such as work stress, general heath quality, etc. on performance of employees. In this paper, we present an empirical investigation to study the effects of work stress, general health, organizational intelligence and job satisfaction on employee performance. The proposed study of this paper uses two questionnaires where one is associated with general heath quality (GHQ with 20 questions and the other one consists of 12 questions, which is associated with work stress. The study chooses a sample of 144 employees from 222 people who worked for one of Islamic Azad University in Iran. Cronbach alphas for work stress, general health, organizational intelligence, job satisfaction and organizational performance are 0.911, 0.895, 0.795, 0.863 and, 0.864, respectively. The results indicate that job satisfaction has the highest influence on organizational performance followed by other factors.

  2. Cumulative trauma and current posttraumatic stress disorder status in general population and inmate samples.

    Science.gov (United States)

    Briere, John; Agee, Elisha; Dietrich, Anne

    2016-07-01

    This research was undertaken to examine the role between cumulative exposure to different types of traumatic events and posttraumatic stress disorder (PTSD) status in general population and prison samples. Two archival datasets were examined: the standardization sample for the Detailed Assessment of Posttraumatic States (DAPS; Briere, 2001), and data from a study on trauma and posttraumatic sequelae among inmates and others. PTSD was found in 4% of the general population sample and 48% of the prison sample. Trauma exposure was very common among prisoners, including a 70% rate of childhood sexual abuse for women and a 50% rate for men. Lifetime number of different types of trauma was associated with PTSD in both the general population and prison samples, even when controlling for the effects of sexual trauma. Cumulative interpersonal trauma predicted PTSD, whereas cumulative noninterpersonal trauma did not. In the general population sample, participants who had only 1 type of trauma exposure had a 0% likelihood of current PTSD, whereas those with 6 or more other trauma types had a 12% likelihood. In the prison sample, those with only 1 type of trauma exposure had a 17% percent likelihood of current PTSD, whereas those exposed to 6 or more other trauma types had a 64% chance of PTSD. Cumulative trauma predicts current PTSD in both general population and prison samples, even after controlling for sexual trauma. PTSD appears to develop generally as a function of exposure to multiple types of interpersonal trauma, as opposed to a single traumatic event. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  3. Correction: General optimization procedure towards the design of a new family of minimal parameter spin-component-scaled double-hybrid density functional theory.

    Science.gov (United States)

    Roch, Loïc M; Baldridge, Kim K

    2018-02-07

    Correction for 'General optimization procedure towards the design of a new family of minimal parameter spin-component-scaled double-hybrid density functional theory' by Loïc M. Roch and Kim K. Baldridge, Phys. Chem. Chem. Phys., 2017, 19, 26191-26200.

  4. Effects of Implementing a Hybrid Wet Lab and Online Module Lab Curriculum into a General Chemistry Course: Impacts on Student Performance and Engagement with the Chemistry Triplet

    Science.gov (United States)

    Irby, Stefan M.; Borda, Emily J.; Haupt, Justin

    2018-01-01

    Here, we describe the implementation a hybrid general chemistry teaching laboratory curriculum that replaces a portion of a course's traditional "wet lab" experiences with online virtual lab modules. These modules intentionally utilize representations on all three levels of the chemistry triplet-macroscopic, submicroscopic, and symbolic.…

  5. The role of general and occupational stress in the relationship between workaholism and work-family/family-work conflicts.

    Science.gov (United States)

    Hauk, Mateusz; Chodkiewicz, Jan

    2013-06-01

    The purpose of this study was to analyze the role of general and occupational stress in the relationship between workaholism (recognized in two ways: as addiction and as behavioral tendency) and the intensity of work-family and family-work conflict. The study included 178 working people. The survey was conducted at three stages - half a year before a holiday, right after the holiday and half a year after the holiday. The Excessive Work Involvement Scale (SZAP) by Golińska for the measurement of workaholism recognized as addiction; The Scale of Workaholism as Behavioral Tendencies (SWBT) by Mudrack and Naughton as adapted by Dudek et al for the measurement of workaholism as behavioral tendency; the Perceived Stress Scale by Cohen et al., as adapted by Juczyński for the measurement of general stress; the Scale of Occupational Stress by Stanton in the adaptation of Dudek and Hauk for measurement of occupational stress; the Scale of Work-Family Conflict WFC/FWC by Netemeyer et al. with the Polish adaptation of A.M. Zalewska. Workaholism was measured once - before a holiday, the explained and intervening variables (the level of conflicts and stress, respectively) were measured at three stages. To test the mediating role of general and occupational stress, hierarchical regression analysis as well as the method of bootstrapping were applied. Our results indicate that general stress is an important mediator of the relationship between workaholism recognized as an addiction and work-family conflicts. Occupational stress turned out to be the only mediator in the relationship between workaholism (recognized as an addiction) and the work-family conflict, noted exclusively in the first stage of the study. Both general and occupational stress were not significant mediators in the relationship between workaholism recognized as a behavioral tendency and the conflicts described.

  6. The role of general and occupational stress in the relationship between workaholism and work-family/family-work conflicts

    Directory of Open Access Journals (Sweden)

    Mateusz Hauk

    2013-06-01

    Full Text Available Introduction: The purpose of this study was to analyze the role of general and occupational stress in the relationship between workaholism (recognized in two ways: as addiction and as behavioral tendency and the intensity of work-family and familywork conflict. Materials and Methods: The study included 178 working people. The survey was conducted at three stages - half a year before a holiday, right after the holiday and half a year after the holiday. The Excessive Work Involvement Scale (SZAP by Golińska for the measurement of workaholism recognized as addiction; The Scale of Workaholism as Behavioral Tendencies (SWBT by Mudrack and Naughton as adapted by Dudek et al for the measurement of workaholism as behavioral tendency; the Perceived Stress Scale by Cohen et al., as adapted by Juczyński for the measurement of general stress; the Scale of Occupational Stress by Stanton in the adaptation of Dudek and Hauk for measurement of occupational stress; the Scale of Work-Family Conflict WFC/FWC by Netemeyer et al. with the Polish adaptation of A.M. Zalewska. Workaholism was measured once - before a holiday, the explained and intervening variables (the level of conflicts and stress, respectively were measured at three stages. To test the mediating role of general and occupational stress, hierarchical regression analysis as well as the method of bootstrapping were applied. Results and Conclusions: Our results indicate that general stress is an important mediator of the relationship between workaholism recognized as an addiction and work-family conflicts. Occupational stress turned out to be the only mediator in the relationship between workaholism (recognized as an addiction and the work-family conflict, noted exclusively in the first stage of the study. Both general and occupational stress were not significant mediators in the relationship between workaholism recognized as a behavioral tendency and the conflicts described.

  7. Reciprocal Genetics: Identifying QTL for General and Specific Combining Abilities in Hybrids Between Multiparental Populations from Two Maize (Zea mays L.) Heterotic Groups.

    Science.gov (United States)

    Giraud, Héloïse; Bauland, Cyril; Falque, Matthieu; Madur, Delphine; Combes, Valérie; Jamin, Philippe; Monteil, Cécile; Laborde, Jacques; Palaffre, Carine; Gaillard, Antoine; Blanchard, Philippe; Charcosset, Alain; Moreau, Laurence

    2017-11-01

    Several plant and animal species of agricultural importance are commercialized as hybrids to take advantage of the heterosis phenomenon. Understanding the genetic architecture of hybrid performances is therefore of key importance. We developed two multiparental maize ( Zea mays L.) populations, each corresponding to an important heterotic group (dent or flint) and comprised of six connected biparental segregating populations of inbred lines (802 and 822 lines for each group, respectively) issued from four founder lines. Instead of using "testers" to evaluate their hybrid values, segregating lines were crossed according to an incomplete factorial design to produce 951 dent-flint hybrids, evaluated for four biomass production traits in eight environments. QTL detection was carried out for the general-combining-ability (GCA) and specific-combining-ability (SCA) components of hybrid value, considering allelic effects transmitted from each founder line. In total, 42 QTL were detected across traits. We detected mostly QTL affecting GCA, 31% (41% for dry matter yield) of which also had mild effects on SCA. The small impact of dominant effects is consistent with the known differentiation between the dent and flint heterotic groups and the small percentage of hybrid variance due to SCA observed in our design (∼20% for the different traits). Furthermore, most (80%) of GCA QTL were segregating in only one of the two heterotic groups. Relative to tester-based designs, use of hybrids between two multiparental populations appears highly cost efficient to detect QTL in two heterotic groups simultaneously. This presents new prospects for selecting superior hybrid combinations with markers. Copyright © 2017 by the Genetics Society of America.

  8. Work Related Stress: Application of a Special Study to the General Business Community.

    Science.gov (United States)

    Gallagher, Denise M.; And Others

    There has been much recent attention given to stress and the negative side effects associated with excessive stress. Employers need to recognize the effect that stress can have on the productivity and attitudes of their employees. To examine work-related stress and to develop stress management strategies, a study was conducted of flight attendants…

  9. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands

    OpenAIRE

    Harmsen, R; Helms-Lorenz, M.; Maulana, R; van Veen, K; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the beginning teachers (BTs) context was investigated using a sample of 356 beginning teachers from 52 different secondary school locations in the Netherlands. Confirmatory Factor Analyses, Principal Compone...

  10. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands.

    OpenAIRE

    Harmsen, Ruth; Helms-Lorenz, Michelle; Maulana, Ridwan; van Veen, Klaas; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the beginning teachers (BTs) context was investigated using a sample of 356 beginning teachers from 52 different secondary school locations in the Netherlands. Confirmatory Factor Analyses, Principal Compone...

  11. General self-efficacy and the effect of hospital workplace violence on doctors' stress and job satisfaction in China.

    Science.gov (United States)

    Yao, Yongcheng; Wang, Wei; Wang, Faxuan; Yao, Wu

    2014-06-01

    This study aims at exploring associations of general self-efficacy (GSE), workplace violence and doctors' work-related attitudes. In this study a cross-sectional survey design was applied. Questionnaires were administrated to 758 doctors working in 9 hospitals of Zhengzhou, Henan province, China, between June and October 2010. General information on age, gender, and years of working was collected, and the doctors' experience and witnessing workplace violence, job satisfaction, job initiative, occupational stress as well as GSE were measured. General linear regression analysis was performed in association analyses. Both experiencing and witnessing workplace violence were significantly positively correlated with the level of occupational stress but significantly negatively correlated with job satisfaction, job initiative, and GSE. General self-efficacy significantly modified relationships between both experiencing and witnessing workplace violence with occupational stress (β = 0.49 for experiencing violence; β = 0.43 for witnessing violence; p violence with job initiative (p > 0.05). The levels of occupational stress declined significantly with the increase of GSE, while job satisfaction increased significantly along with its increase. The effects of GSE on occupational stress and job satisfaction weakened as the frequency of violence increased. The findings suggest that GSE can modify effects of workplace violence on health care workers' stress and job satisfaction. Enhancing GSE in combination with stress reduction may lead to facilitating health care workers' recovery from workplace violence, and thereby improving their work-related attitudes.

  12. General self-efficacy and the effect of hospital workplace violence on doctors’ stress and job satisfaction in China

    Directory of Open Access Journals (Sweden)

    Yongcheng Yao

    2014-08-01

    Full Text Available Objectives: This study aims at exploring associations of general self-efficacy (GSE, workplace violence and doctors' work-related attitudes. Material and Methods: In this study a cross-sectional survey design was applied. Questionnaires were administrated to 758 doctors working in 9 hospitals of Zhengzhou, Henan province, China, between June and October 2010. General information on age, gender, and years of working was collected, and the doctors' experience and witnessing workplace violence, job satisfaction, job initiative, occupational stress as well as GSE were measured. General linear regression analysis was performed in association analyses. Results: Both experiencing and witnessing workplace violence were significantly positively correlated with the level of occupational stress but significantly negatively correlated with job satisfaction, job initiative, and GSE. General self-efficacy significantly modified relationships between both experiencing and witnessing workplace violence with occupational stress (β = 0.49 for experiencing violence; β = 0.43 for witnessing violence; p 0.05. The levels of occupational stress declined significantly with the increase of GSE, while job satisfaction increased significantly along with its increase. The effects of GSE on occupational stress and job satisfaction weakened as the frequency of violence increased. Conclusions: The findings suggest that GSE can modify effects of workplace violence on health care workers' stress and job satisfaction. Enhancing GSE in combination with stress reduction may lead to facilitating health care workers' recovery from workplace violence, and thereby improving their work-related attitudes.

  13. Dimensional structure of DSM-5 posttraumatic stress symptoms: support for a hybrid Anhedonia and Externalizing Behaviors model.

    Science.gov (United States)

    Armour, Cherie; Tsai, Jack; Durham, Tory A; Charak, Ruby; Biehn, Tracey L; Elhai, Jon D; Pietrzak, Robert H

    2015-02-01

    Several revisions to the symptom clusters of posttraumatic stress disorder (PTSD) have been made in the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Central to the focus of this study was the revision of PTSD's tripartite structure in DSM-IV into four symptom clusters in DSM-5. Emerging confirmatory factor analytic (CFA) studies have suggested that DSM-5 PTSD symptoms may be best represented by one of two 6-factor models: (1) an Externalizing Behaviors model characterized by a factor which combines the irritability/anger and self-destructive/reckless behavior items; and (2) an Anhedonia model characterized by items of loss of interest, detachment, and restricted affect. The current study conducted CFAs of DSM-5 PTSD symptoms assessed using the PTSD Checklist for DSM-5 (PCL-5) in two independent and diverse trauma-exposed samples of a nationally representative sample of 1484 U.S. veterans and a sample of 497 Midwestern U.S. university undergraduate students. Relative fits of the DSM-5 model, the DSM-5 Dysphoria model, the DSM-5 Dysphoric Arousal model, the two 6-factor models, and a newly proposed 7-factor Hybrid model, which consolidates the two 6-factor models, were evaluated. Results revealed that, in both samples, both 6-factor models provided significantly better fit than the 4-factor DSM-5 model, the DSM-5 Dysphoria model and the DSM-5 Dysphoric Arousal model. Further, the 7-factor Hybrid model, which incorporates key features of both 6-factor models and is comprised of re-experiencing, avoidance, negative affect, anhedonia, externalizing behaviors, and anxious and dysphoric arousal symptom clusters, provided superior fit to the data in both samples. Results are discussed in light of theoretical and empirical support for the latent structure of DSM-5 PTSD symptoms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Hybrid micro/nanostructural surface offering improved stress distribution and enhanced osseointegration properties of the biomedical titanium implant.

    Science.gov (United States)

    Hou, Ping-Jen; Ou, Keng-Liang; Wang, Chin-Chieh; Huang, Chiung-Fang; Ruslin, Muhammad; Sugiatno, Erwan; Yang, Tzu-Sen; Chou, Hsin-Hua

    2018-03-01

    The aim of the present study was to investigate the surface characteristic, biomechanical behavior, hemocompatibility, bone tissue response and osseointegration of the optimal micro-arc oxidation surface-treated titanium (MST-Ti) dental implant. The surface characteristic, biomechanical behavior and hemocompatibility of the MST-Ti dental implant were performed using scanning electron microscope, finite element method, blood dripping and immersion tests. The mini-pig model was utilized to evaluate the bone tissue response and osseointegration of the MST-Ti dental implant in vivo. Data were analyzed by analysis of variance using the Student's t-test (P ≤ 0.05). The hybrid volcano-like micro/nanoporous structure was formed on the surface of the MST-Ti dental implant. The hybrid volcano-like micro/nanoporous surface played an important role to improve the stress transfer between fixture, cortical bone and cancellous bone for the MST-Ti dental implant. Moreover, the MST-Ti implant was considered to have the outstanding hemocompatibility. In vivo testing results showed that the bone-to-implant contact (BIC) ratio significantly altered as the implant with micro/nanoporous surface. After 12 weeks of implantation, the MST-Ti dental implant group exhibited significantly higher BIC ratio than the untreated dental implant group. In addition, the MST-Ti dental implant group also presented an enhancing osseointegration, particularly in the early stages of bone healing. It can be concluded that the micro-arc oxidation approach induced the formation of micro/nanoporous surface is a promising and reliable alternative surface modification for Ti dental implant applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Psychophysiologic responsivity in posttraumatic stress disorder: generalized hyperresponsiveness versus trauma specificity.

    Science.gov (United States)

    Casada, J H; Amdur, R; Larsen, R; Liberzon, I

    1998-11-15

    Clinically, subjects with posttraumatic stress disorder (PTSD) are viewed as hyperresponsive to a variety of stimuli. Psychophysiologic studies, however, have demonstrated hyperresponsiveness only to stimuli that are closely related to the original trauma. This set of experiments uses a variety of stimuli that vary in trauma-relatedness, arousal level, sensory modality stimulated, and degree of cognitive processing demanded to assess the extent of generalization of physiologic responses. Heart rate (HR), frontal electromyogram (EMG), and skin conductance (EDG) responses were measured during presentation of each stimulus. PTSD subjects (n = 15) had an elevated baseline EDG and increased HR and EMG responses to the trauma-related stimulus (combat sounds) compared to normal control subjects (n = 11) and combat control subjects (n = 10). No significant differences were noted between PTSD and control groups in response to non-trauma-related arousing stimuli. These results suggest that the physiologic hyperresponsivity of PTSD subjects is limited to stimuli closely associated with the inciting trauma.

  16. Various methods of numerical estimation of generalized stress intensity factors of bi-material notches

    Directory of Open Access Journals (Sweden)

    Klusák J.

    2009-12-01

    Full Text Available The study of bi-material notches becomes a topical problem as they can model efficiently geometrical or material discontinuities. When assessing crack initiation conditions in the bi-material notches, the generalized stress intensity factors H have to be calculated. Contrary to the determination of the K-factor for a crack in an isotropic homogeneous medium, for the ascertainment of the H-factor there is no procedure incorporated in the calculation systems. The calculation of these fracture parameters requires experience. Direct methods of estimation of H-factors need choosing usually length parameter entering into calculation. On the other hand the method combining the application of the reciprocal theorem (Ψ-integral and FEM does not require entering any length parameter and is capable to extract the near-tip information directly from the far-field deformation.

  17. Assessing traumatic event exposure: general issues and preliminary findings for the Stressful Life Events Screening Questionnaire.

    Science.gov (United States)

    Goodman, L A; Corcoran, C; Turner, K; Yuan, N; Green, B L

    1998-07-01

    This article reviews the psychometric properties of the Stressful Life Events Screening Questionnaire (SLESQ), a recently developed trauma history screening measure, and discusses the complexities involved in assessing trauma exposure. There are relatively few general measures of exposure to a variety of types of traumatic events, and most of those that exist have not been subjected to rigorous psychometric evaluation. The SLESQ showed good test-retest reliability, with a median kappa of .73, adequate convergent validity (with a lengthier interview) with a median kappa of .64, and good discrimination between Criterion A and non-Criterion A events. The discussion addresses some of the challenges of assessing traumatic event exposure along the dimensions of defining traumatic events, assessment methodologies, reporting consistency, and incident validation.

  18. A closed-loop hybrid physiological model relating to subjects under physical stress.

    Science.gov (United States)

    El-Samahy, Emad; Mahfouf, Mahdi; Linkens, Derek A

    2006-11-01

    The objective of this research study is to derive a comprehensive physiological model relating to subjects under physical stress conditions. The model should describe the behaviour of the cardiovascular system, respiratory system, thermoregulation and brain activity in response to physical workload. An experimental testing rig was built which consists of recumbent high performance bicycle for inducing the physical load and a data acquisition system comprising monitors and PCs. The signals acquired and used within this study are the blood pressure, heart rate, respiration, body temperature, and EEG signals. The proposed model is based on a grey-box based modelling approach which was used because of the sufficient level of details it provides. Cardiovascular and EEG Data relating to 16 healthy subject volunteers (data from 12 subjects were used for training/validation and the data from 4 subjects were used for model testing) were collected using the Finapres and the ProComp+ monitors. For model validation, residual analysis via the computing of the confidence intervals as well as related histograms was performed. Closed-loop simulations for different subjects showed that the model can provide reliable predictions for heart rate, blood pressure, body temperature, respiration, and the EEG signals. These findings were also reinforced by the residual analyses data obtained, which suggested that the residuals were within the 90% confidence bands and that the corresponding histograms were of a normal distribution. A higher intelligent level was added to the model, based on neural networks, to extend the capabilities of the model to predict over a wide range of subjects dynamics. The elicited physiological model describing the effect of physiological stress on several physiological variables can be used to predict performance breakdown of operators in critical environments. Such a model architecture lends itself naturally to exploitation via feedback control in a 'reverse

  19. Performance of two-lobe hole-entry hybrid journal bearing system under the combined influence of textured surface and couple stress lubricant

    Science.gov (United States)

    Khatri, Chandra B.; Sharma, Satish C.

    2018-02-01

    Textured surface in journal bearings is becoming an important area of investigation during the last few years. Surface textures have the shapes of micro-dimple with a small diameter and depth having order of magnitude of bearing clearance. This paper presents the influence of couple stress lubricant on the circular and non-circular hole-entry hybrid journal bearing system and reports the comparative study between the textured and non-textured circular/non-circular hybrid journal bearing system. The governing Reynolds equation has been modified for the couple stress lubricant flow in the clearance of bearing and journal. The FEM technique has been applied to solve the modified Reynolds equation together with restrictor flow equation. The numerically simulated results indicate that the influence of couple stress lubricant is significantly more in textured journal bearing than that of non-textured journal bearing. Further, it has been observed that the textured two-lobe (δ = 1.1) hybrid journal bearing lubricated with couple stress lubricant provides larger values of fluid film stiffness coefficients and stability threshold speed against other bearings studied in the present paper.

  20. High workload and job stress are associated with lower practice performance in general practice: an observational study in 239 general practices in the Netherlands

    Directory of Open Access Journals (Sweden)

    Grol Richard

    2009-07-01

    Full Text Available Abstract Background The impact of high physician workload and job stress on quality and outcomes of healthcare delivery is not clear. Our study explored whether high workload and job stress were associated with lower performance in general practices in the Netherlands. Methods Secondary analysis of data from 239 general practices, collected in practice visits between 2003 to 2006 in the Netherlands using a comprehensive set of measures of practice management. Data were collected by a practice visitor, a trained non-physician observer using patients questionnaires, doctors and staff. For this study we selected five measures of practice performance as outcomes and six measures of GP workload and job stress as predictors. A total of 79 indicators were used out of the 303 available indicators. Random coefficient regression models were applied to examine associations. Results and discussion Workload and job stress are associated with practice performance. Workload: Working more hours as a GP was associated with more positive patient experiences of accessibility and availability (b = 0.16. After list size adjustment, practices with more GP-time per patient scored higher on GP care (b = 0.45. When GPs provided more than 20 hours per week per 1000 patients, patients scored over 80% on the Europep questionnaire for quality of GP care. Job stress: High GP job stress was associated with lower accessibility and availability (b = 0.21 and insufficient practice management (b = 0.25. Higher GP commitment and more satisfaction with the job was associated with more prevention and disease management (b = 0.35. Conclusion Providing more time in the practice, and more time per patient and experiencing less job stress are all associated with perceptions by patients of better care and better practice performance. Workload and job stress should be assessed by using list size adjusted data in order to realise better quality of care. Organisational development using

  1. High workload and job stress are associated with lower practice performance in general practice: an observational study in 239 general practices in the Netherlands.

    Science.gov (United States)

    van den Hombergh, Pieter; Künzi, Beat; Elwyn, Glyn; van Doremalen, Jan; Akkermans, Reinier; Grol, Richard; Wensing, Michel

    2009-07-15

    The impact of high physician workload and job stress on quality and outcomes of healthcare delivery is not clear. Our study explored whether high workload and job stress were associated with lower performance in general practices in the Netherlands. Secondary analysis of data from 239 general practices, collected in practice visits between 2003 to 2006 in the Netherlands using a comprehensive set of measures of practice management. Data were collected by a practice visitor, a trained non-physician observer using patients questionnaires, doctors and staff. For this study we selected five measures of practice performance as outcomes and six measures of GP workload and job stress as predictors. A total of 79 indicators were used out of the 303 available indicators. Random coefficient regression models were applied to examine associations. Workload and job stress are associated with practice performance.Workload: Working more hours as a GP was associated with more positive patient experiences of accessibility and availability (b = 0.16). After list size adjustment, practices with more GP-time per patient scored higher on GP care (b = 0.45). When GPs provided more than 20 hours per week per 1000 patients, patients scored over 80% on the Europep questionnaire for quality of GP care.Job stress: High GP job stress was associated with lower accessibility and availability (b = 0.21) and insufficient practice management (b = 0.25). Higher GP commitment and more satisfaction with the job was associated with more prevention and disease management (b = 0.35). Providing more time in the practice, and more time per patient and experiencing less job stress are all associated with perceptions by patients of better care and better practice performance. Workload and job stress should be assessed by using list size adjusted data in order to realise better quality of care. Organisational development using this kind of data feedback could benefit both patients and GP.

  2. Stress tensor and viscosity of water: Molecular dynamics and generalized hydrodynamics results

    Science.gov (United States)

    Bertolini, Davide; Tani, Alessandro

    1995-08-01

    The time correlation functions (CF's) of diagonal and off-diagonal components of the stress tensor of water have been calculated at 245 and 298 K in a molecular dynamics (MD) study on 343 molecules in the microcanonical ensemble. We present results obtained at wave number k=0 and at a few finite values of k, in the atomic and molecular formalism. In all cases, more than 98% of these functions are due to the potential term of the stress tensor. At k=0, their main features are a fast oscillatory initial decay, followed by a long-time tail more apparent in the supercooled region. Bulk and shear viscosities, calculated via Green-Kubo integration of the relevant CF at k=0, are underestimated with respect to experimental data, mainly at low temperature, but their ratio (~=2) is correctly reproduced. Both shear and bulk viscosity decrease as a function of k, the latter more rapidly, so that they become almost equal at ~=1 Å-1. Also, both viscosities drop rapidly from their maximum at ω=0. This behavior has been related to the large narrowing observed in the acoustic band, mainly in the supercooled region. The infinite frequency bulk and shear rigidity moduli have been shown to be in fair agreement with the experimental data, provided the MD value used for comparison is that corresponding to the frequency range relevant to ultrasonic measurements. The MD results of stress-stress CF's compare well with those predicted by Bertolini and Tani [Phys. Rev. E 51, 1091 (1995)] at k=0, by an application of generalized hydrodynamics [de Schepper et al., Phys. Rev. A 38, 271 (1988)] in the molecular formalism, to the same model of water (TIP4P) [Jorgensen et al., J. Chem. Phys. 79, 926 (1983)]. These CF's are essentially equal in the atomic and molecular formalism, the only minor difference being restricted to the high frequency librational region of the shear function. By a comparison of atomic and molecular results, we show here that neglecting libration has no effect on the

  3. On the determination of general plane stress states in orthotropic materials from ultrasonic velocity data in non symmetry planes

    International Nuclear Information System (INIS)

    Goncalves Filho, Orlando J.A.

    2015-01-01

    This work reports the progress in the development of a new experimental protocol for plane stress determination in orthotropic materials based on the ultrasonic velocity of bulk waves propagating in non symmetry planes with oblique incidence. The presence of stress-induced deformation introduces an acoustic anisotropy in the material in addition to that defined by its texture. Orthotropic materials under general plane stress states become acoustically monoclic and its orthotropic planes orthogonal to the stress plane become non symmetry planes. The inverse solution of the generalized Christoffel equation for ultrasonic bulk waves propagating in non symmetry planes of anisotropic bodies is known to be numerically unstable. The suggested protocol deals with this numerical instability without recourse to bulk wave propagation in the stress plane as proposed in the literature. Hence, it should be useful for plane stress analysis of thin wall pressure vessels where ultrasonic measurements in the direction of the wall plane are not possible. For the initial validation of the suggested protocol and verification of the stability of the inversion algorithm, computer simulation of stress determination have been performed from synthetic sets of velocity data obtained by the forward solution of the generalized Christoffel equation. Preliminary results for slightly orthotropic aluminium highlight the potential of the suggested protocol. (author)

  4. Prior stress promotes the generalization of contextual fear memories: Involvement of the gabaergic signaling within the basolateral amygdala complex.

    Science.gov (United States)

    Bender, C L; Otamendi, A; Calfa, G D; Molina, V A

    2018-04-20

    Fear generalization occurs when a response, previously acquired with a threatening stimulus, is transferred to a similar one. However, it could be maladaptive when stimuli that do not represent a real threat are appraised as dangerous, which is a hallmark of several anxiety disorders. Stress exposure is a major risk factor for the occurrence of anxiety disorders and it is well established that it influences different phases of fear memory; nevertheless, its impact on the generalization of contextual fear memories has been less studied. In the present work, we have characterized the impact of acute restraint stress prior to contextual fear conditioning on the generalization of this fear memory, and the role of the GABAergic signaling within the basolateral amygdala complex (BLA) on the stress modulatory effects. We have found that a single stress exposure promoted the generalization of this memory trace to a different context that was well discriminated in unstressed conditioned animals. Moreover, this effect was dependent on the formation of a contextual associative memory and on the testing order (i.e., conditioning context first vs generalization context first). Furthermore, we observed that increasing GABA-A signaling by intra-BLA midazolam administration prior to the stressful session exposure prevented the generalization of fear memory, whereas intra-BLA administration of the GABA-A antagonist (Bicuculline), prior to fear conditioning, induced the generalization of fear memory in unstressed rats. We concluded that stress exposure, prior to contextual fear conditioning, promotes the generalization of fear memory and that the GABAergic transmission within the BLA has a critical role in this phenomenon. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Towards a model for understanding the development of post-traumatic stress and general distress in mental health nurses.

    Science.gov (United States)

    Lee, Joyce; Daffern, Michael; Ogloff, James R P; Martin, Trish

    2015-02-01

    In their daily work, mental health nurses (MHN) are often exposed to stressful events, including patient-perpetrated aggression and violence. Personal safety and health concerns, as well as concern for the physical and psychological well-being of patients, dominate; these concerns have a profound impact on nurses. This cross-sectional study explored and compared the psychological well-being of 196 hospital-based MHN (97 forensic and 99 mainstream registered psychiatric nurses or psychiatric state enrolled nurses). The aim was to examine exposure to inpatient aggression and work stress, and identify factors contributing to the development of post-traumatic stress reactions and general distress. Multiple regression analyses indicated that working in a mainstream setting is associated with increased work stress; however, mainstream and forensic nurses experienced similar psychological well-being. As a group, 14-17% of mainstream and forensic nurses met the diagnostic criteria for post-traumatic stress disorder, and 36% scored above the threshold for psychiatric caseness. A tentative model of post-traumatic stress and general distress in nurses was developed, illustrating the impact of aggression and stress on well-being. The present study affirms that mental health nursing is a challenging and stressful occupation. Implications for organizations, managers, and individual nurses are discussed. © 2014 Australian College of Mental Health Nurses Inc.

  6. Assessment of Reynolds stresses tensor reconstruction methods for synthetic turbulent inflow conditions. Application to hybrid RANS/LES methods

    International Nuclear Information System (INIS)

    Laraufie, Romain; Deck, Sébastien

    2013-01-01

    Highlights: • Present various Reynolds stresses reconstruction methods from a RANS-SA flow field. • Quantify the accuracy of the reconstruction methods for a wide range of Reynolds. • Evaluate the capabilities of the overall process (Reconstruction + SEM). • Provide practical guidelines to realize a streamwise RANS/LES (or WMLES) transition. -- Abstract: Hybrid or zonal RANS/LES approaches are recognized as the most promising way to accurately simulate complex unsteady flows under current computational limitations. One still open issue concerns the transition from a RANS to a LES or WMLES resolution in the stream-wise direction, when near wall turbulence is involved. Turbulence content has then to be prescribed at the transition to prevent from turbulence decay leading to possible flow relaminarization. The present paper aims to propose an efficient way to generate this switch, within the flow, based on a synthetic turbulence inflow condition, named Synthetic Eddy Method (SEM). As the knowledge of the whole Reynolds stresses is often missing, the scope of this paper is focused on generating the quantities required at the SEM inlet from a RANS calculation, namely the first and second order statistics of the aerodynamic field. Three different methods based on two different approaches are presented and their capability to accurately generate the needed aerodynamic values is investigated. Then, the ability of the combination SEM + Reconstruction method to manufacture well-behaved turbulence is demonstrated through spatially developing flat plate turbulent boundary layers. In the mean time, important intrinsic features of the Synthetic Eddy method are pointed out. The necessity of introducing, within the SEM, accurate data, with regards to the outer part of the boundary layer, is illustrated. Finally, user’s guidelines are given depending on the Reynolds number based on the momentum thickness, since one method is suitable for low Reynolds number while the

  7. Trace anomaly of the stress-energy tensor for massless vector particles propagating in a general background metric

    International Nuclear Information System (INIS)

    Adler, S.L.; Lieberman, J.

    1978-01-01

    We reanalyze the problem of regularization of the stress-energy tensor for massless vector particles propating in a general background metric, using covariant point separation techniques applied to the Hadamard elementary solution. We correct an error, point out by Wald, in the earlier formulation of Adler, Lieberman, and Ng, and find a stress-energy tensor trace anomaly agreeing with that found by other regularization methods

  8. Stress, coping, and general health of nurses who work in units that assist AIDS-carriers and patients with

    OpenAIRE

    Da Silva Britto, Eliane; Pimenta Carvalho, Ana Maria

    2008-01-01

    Based on Lazarus and Folkman’s theory about stress and coping, this research aimed at answering questions related to how nurses, who work in two specialized units of a general hospital, evaluate their working environment, their health and how they manage with stressing situations. In the unit of infectious diseases, the nurses’ evaluation of their working environment did not surpass the limits of what is considered as acceptable. In the unit of hematological alterations, the results showed hi...

  9. Stress

    Science.gov (United States)

    ... can be life-saving. But chronic stress can cause both physical and mental harm. There are at least three different types of stress: Routine stress related to the pressures of work, family, and other daily responsibilities Stress brought about ...

  10. Life Stress, Strain, and Deviance Across Schools: Testing the Contextual Version of General Strain Theory in China.

    Science.gov (United States)

    Zhang, Jinwu; Liu, Jianhong; Wang, Xin; Zou, Anquan

    2017-08-01

    General Strain Theory delineates different types of strain and intervening processes from strain to deviance and crime. In addition to explaining individual strain-crime relationship, a contextualized version of general strain theory, which is called the Macro General Strain Theory, has been used to analyze how aggregate variables influence aggregate and individual deviance and crime. Using a sample of 1,852 students (Level 1) nested in 52 schools (Level 2), the current study tests the Macro General Strain Theory using Chinese data. The results revealed that aggregate life stress and strain have influences on aggregate and individual deviance, and reinforce the individual stress-deviance association. The current study contributes by providing the first Macro General Strain Theory test based on Chinese data and offering empirical evidence for the multilevel intervening processes from strain to deviance. Limitations and future research directions are discussed.

  11. Conserved ABC Transport System Regulated by the General Stress Response Pathways of Alpha- and Gammaproteobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Herrou, Julien; Willett, Jonathan W.; Czy; #380; , Daniel M.; Babnigg, Gyorgy; Kim, Youngchang; Crosson, Sean (UC)

    2016-12-19

    ABSTRACT

    Brucella abortusσE1is an EcfG family sigma factor that regulates the transcription of dozens of genes in response to diverse stress conditions and is required for maintenance of chronic infection in a mouse model. A putative ATP-binding cassette transporter operon,bab1_0223-bab1_0226, is among the most highly activated gene sets in the σE1regulon. The proteins encoded by the operon resemble quaternary ammonium-compatible solute importers but are most similar in sequence to the broadly conserved YehZYXW system, which remains largely uncharacterized. Transcription ofyehZYXWis activated by the general stress sigma factor σSinEnterobacteriaceae, which suggests a functional role for this transport system in bacterial stress response across the classesAlphaproteobacteriaandGammaproteobacteria. We present evidence thatB. abortusYehZYXW does not function as an importer of known compatible solutes under physiological conditions and does not contribute to the virulence defect of a σE1-null strain. The solein vitrophenotype associated with genetic disruption of this putative transport system is reduced growth in the presence of high Li+ion concentrations. A crystal structure ofB. abortusYehZ revealed a class II periplasmic binding protein fold with significant structural homology toArchaeoglobus fulgidusProX, which binds glycine betaine. However, the structure

  12. Tryptophan depletion affects the autonomic stress response in generalized social anxiety disorder.

    Science.gov (United States)

    van Veen, J Frederieke; van Vliet, Irene M; de Rijk, Roel H; van Pelt, Johannes; Mertens, Bart; Fekkes, Durk; Zitman, Frans G

    2009-11-01

    In generalized social anxiety disorder (gSAD), serotonergic dysfunctions are found, as well as abnormalities of the autonomic nervous system (ANS) in basal conditions and of the hypothalamic pituitary adrenal (HPA) axis in response to psychological challenges. These findings raise the question whether these phenomena are interrelated. Therefore we designed a study in which two groups with nine pair wise age and gender matched gSAD patients (total of 10 men and 8 women), who were successfully treated with a selective serotonin reuptake inhibitor (SSRI), underwent a tryptophan depletion challenge (TD) or a placebo condition. A TD procedure temporarily decreases serotonergic neurotransmission. In order to activate the stress system the TD/placebo challenge was combined with a public speaking task. We assessed ANS responses, as measured with the promising new marker salivary alpha-amylase (sAA), and HPA-axis responses, as measured with salivary cortisol. The most important result was that the TD group showed a significant larger sAA response to the public speaking task as compared to the placebo group, reflecting hyperresponsivity of the ANS in this group, whereas no differences were seen in cortisol responses. This suggests that in gSAD there is a vulnerability of the ANS more than the HPA-axis.

  13. THE IMPACT OF STRESSFUL LIFE EVENTS ON RELAPSE OF GENERALIZED ANXIETY DISORDER

    Science.gov (United States)

    Francis, Jennifer L.; Moitra, Ethan; Dyck, Ingrid; Keller, Martin B.

    2013-01-01

    Background Stressful life events (SLEs) are associated with the onset of psychiatric disorders but little is known about the effects of SLEs on individuals already diagnosed with an anxiety disorder, particularly generalized anxiety disorder (GAD) in which worry about life events is a defining characteristic. This study examined the impact of SLEs on relapse in adults already diagnosed with GAD. Methods Data are obtained from the Harvard/Brown Anxiety Research Project (HARP), a naturalistic longitudinal study of adults with a current or past history of anxiety disorders. One hundred and twelve adults recovered from an episode of GAD and 27 subsequently relapsed during the study. Eight categories of SLEs were assessed via interview and were examined as predictors of GAD relapse. Results An increased total number of SLEs was associated with a higher cumulative probability of relapse into episode of GAD and there was a nonsignificant statistical trend indicating specific categories of SLEs including health, death, and family/friends/household were related to an increased probability of relapse into episodes of GAD. Conclusions SLEs impact the course of GAD and certain types of stressors may be more relevant to symptomatology than others. The change and uncertainty associated with SLEs may exacerbate existing worry tendencies even among those who have recovered from GAD. PMID:22431499

  14. General Synthesis of Transition-Metal Oxide Hollow Nanospheres/Nitrogen-Doped Graphene Hybrids by Metal-Ammine Complex Chemistry for High-Performance Lithium-Ion Batteries.

    Science.gov (United States)

    Chen, Jiayuan; Wu, Xiaofeng; Gong, Yan; Wang, Pengfei; Li, Wenhui; Mo, Shengpeng; Peng, Shengpan; Tan, Qiangqiang; Chen, Yunfa

    2018-02-09

    We present a general and facile synthesis strategy, on the basis of metal-ammine complex chemistry, for synthesizing hollow transition-metal oxides (Co 3 O 4 , NiO, CuO-Cu 2 O, and ZnO)/nitrogen-doped graphene hybrids, potentially applied in high-performance lithium-ion batteries. The oxygen-containing functional groups of graphene oxide play a prerequisite role in the formation of hollow transition-metal oxides on graphene nanosheets, and a significant hollowing process occurs only when forming metal (Co 2+ , Ni 2+ , Cu 2+ , or Zn 2+ )-ammine complex ions. Moreover, the hollowing process is well correlated with the complexing capacity between metal ions and NH 3 molecules. The significant hollowing process occurs for strong metal-ammine complex ions including Co 2+ , Ni 2+ , Cu 2+ , and Zn 2+ ions, and no hollow structures formed for weak and/or noncomplex Mn 2+ and Fe 3+ ions. Simultaneously, this novel strategy can also achieve the direct doping of nitrogen atoms into the graphene framework. The electrochemical performance of two typical hollow Co 3 O 4 or NiO/nitrogen-doped graphene hybrids was evaluated by their use as anodic materials. It was demonstrated that these unique nanostructured hybrids, in contrast with the bare counterparts, solid transition-metal oxides/nitrogen-doped graphene hybrids, perform with significantly improved specific capacity, superior rate capability, and excellent capacity retention. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. The relationship between stressful working conditions and high alcohol consumption and severe alcohol problems in an urban general population

    DEFF Research Database (Denmark)

    Romelsjö, A; Hasin, D; Hilton, M

    1992-01-01

    The relationship between 15 measures of stressful working conditions and high alcohol consumption (35 g 100% ethanol per day or more for men and 25 g or more for women) was studied, using cross-sectional data from a general population survey of 1344 males and 1494 females; the ages 25-64 years......-adjusted odds ratios, were positive and some were negative when high alcohol consumption was the endpoint, but there was a clear variation by sex and social class. Generally the positive associations were stronger among male non-manual employees. Among males, there was a clear association between stressful...... increased odds ratios were lower when subjects with an alcohol diagnosis at inpatient care during 1980-84 were excluded in the analyses. On the whole, our findings are not conclusive. The strong, but imprecise associations between stressful working conditions and severe alcohol problems, are however...

  16. A third order accurate Lagrangian finite element scheme for the computation of generalized molecular stress function fluids

    DEFF Research Database (Denmark)

    Fasano, Andrea; Rasmussen, Henrik K.

    2017-01-01

    A third order accurate, in time and space, finite element scheme for the numerical simulation of three- dimensional time-dependent flow of the molecular stress function type of fluids in a generalized formu- lation is presented. The scheme is an extension of the K-BKZ Lagrangian finite element me...

  17. Comparison of stresses on homogeneous spheroids in the optical stretcher computed with geometrical optics and generalized Lorenz-Mie theory.

    Science.gov (United States)

    Boyde, Lars; Ekpenyong, Andrew; Whyte, Graeme; Guck, Jochen

    2012-11-20

    We present two electromagnetic frameworks to compare the surface stresses on spheroidal particles in the optical stretcher (a dual-beam laser trap that can be used to capture and deform biological cells). The first model is based on geometrical optics (GO) and limited in its applicability to particles that are much greater than the incident wavelength. The second framework is more sophisticated and hinges on the generalized Lorenz-Mie theory (GLMT). Despite the difference in complexity between both theories, the stress profiles computed with GO and GLMT are in good agreement with each other (relative errors are on the order of 1-10%). Both models predict a diminishing of the stresses for larger wavelengths and a strong increase of the stresses for shorter laser-cell distances. Results indicate that surface stresses on a spheroid with an aspect ratio of 1.2 hardly differ from the stresses on a sphere of similar size. Knowledge of the surface stresses and whether or not they redistribute during the stretching process is of crucial importance in real-time applications of the stretcher that aim to discern the viscoelastic properties of cells for purposes of cell characterization, sorting, and medical diagnostics.

  18. Effects of Salinity Stress on Morphological and Physiological Characteristics of some Local Landrace and Inter specific Hybrids of Cucurbits Seedlings as Rootstocks

    Directory of Open Access Journals (Sweden)

    Ali Farhadi

    2017-12-01

    Full Text Available Introduction: Salinity stress is regarded as one of the most important abiotic factors in plant limiting growth, particularly in arid and semi-arid regions. The reduction of plant growth by salinity stress has been well documented. When water supply is limited, plant structure is modified by increasing the root: shoot ratio. To reduce of losses in vegetative growth and production of plant and to improve water use efficiency under saline conditions in high-yielding genotypes grafting them onto rootstocks could bereduced the effect of saline stress on plant shoot. Grafting is a routine technique in continuous cropping systems. Most of the species of cucurbits are distributed in the dry regions. The objective of this studywas investigated the effectiveness of salinity stress on accessions of cucurbita and hybrid inter specific which enter from another country to Iran. Materials and Methods: This research was conducted in laboratory and greenhouse at the Research Center of Agricultural and Natural Resources of Isfahan during 2013-2014 growing season. A factorial experiment based on completely randomized design with three replications was conducted for rootstock and irrigation water salinity.. In the first experiment 25 seeds of rootstocks were sown in petri dishes with 10 cm diameter and irrigated by 10 ml of saline water. Rootstocks included 20 different local landraces and interspecific hybrids (C.moschata cv. Isfahan and Koshk, C.pepo cv. Alvar, Tiran, Koshk and Asgharabad, C. maxima cv. Kermanshah, Shahreza, Mohamadiyeh and Alvar, Lagenaria Siceraria, Luffa cylindrica, Trichosanthes cucumerina, RZ-Ferro, Es113, Ews910, Ews909, Ews913, 426 and Es152. Salinity stress was 6 levels (0, 2, 4, 6, 8 and 10 ds/m of NaCl. Germination, diameter of stem, height of root and stem, shoot and root fresh mass, vigor index and root: shoot ratio were evaluated. In the second experiment seeds were sown in plastic pot by soil media. Seedlings were irrigated daily

  19. Predictability and interpretability of hybrid link-level crash frequency models for urban arterials compared to cluster-based and general negative binomial regression models.

    Science.gov (United States)

    Najaf, Pooya; Duddu, Venkata R; Pulugurtha, Srinivas S

    2018-03-01

    Machine learning (ML) techniques have higher prediction accuracy compared to conventional statistical methods for crash frequency modelling. However, their black-box nature limits the interpretability. The objective of this research is to combine both ML and statistical methods to develop hybrid link-level crash frequency models with high predictability and interpretability. For this purpose, M5' model trees method (M5') is introduced and applied to classify the crash data and then calibrate a model for each homogenous class. The data for 1134 and 345 randomly selected links on urban arterials in the city of Charlotte, North Carolina was used to develop and validate models, respectively. The outputs from the hybrid approach are compared with the outputs from cluster-based negative binomial regression (NBR) and general NBR models. Findings indicate that M5' has high predictability and is very reliable to interpret the role of different attributes on crash frequency compared to other developed models.

  20. Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part II: responses in the leaves and general conclusions.

    Science.gov (United States)

    Vanhoudt, Nathalie; Cuypers, Ann; Horemans, Nele; Remans, Tony; Opdenakker, Kelly; Smeets, Karen; Bello, Daniel Martinez; Havaux, Michel; Wannijn, Jean; Van Hees, May; Vangronsveld, Jaco; Vandenhove, Hildegarde

    2011-06-01

    The cellular redox balance seems an important modulator under heavy metal stress. While for other heavy metals these processes are well studied, oxidative stress related responses are also known to be triggered under uranium stress but information remains limited. This study aimed to further unravel the mechanisms by which plants respond to uranium stress. Seventeen-day-old Arabidopsis thaliana seedlings, grown on a modified Hoagland solution under controlled conditions, were exposed to 0, 0.1, 1, 10 and 100 μM uranium for 1, 3 and 7 days. While in Part I of this study oxidative stress related responses in the roots were discussed, this second Part II discusses oxidative stress related responses in the leaves and general conclusions drawn from the results of the roots and the leaves will be presented. As several responses were already visible following 1 day exposure, when uranium concentrations in the leaves were negligible, a root-to-shoot signaling system was suggested in which plastids could be important sensing sites. While lipid peroxidation, based on the amount of thiobarbituric acid reactive compounds, was observed after exposure to 100 μM uranium, affecting membrane structure and function, a transient concentration dependent response pattern was visible for lipoxygenase initiated lipid peroxidation. This transient character of uranium stress responses in leaves was emphasized by results of lipoxygenase (LOX2) and antioxidative enzyme transcript levels, enzyme capacities and glutathione concentrations both in time as with concentration. The ascorbate redox balance seemed an important modulator of uranium stress responses in the leaves as in addition to the previous transient responses, the total ascorbate concentration and ascorbate/dehydroascorbate redox balance increased in a concentration and time dependent manner. This could represent either a slow transient response or a stable increase with regard to plant acclimation to uranium stress. Copyright

  1. Stress.

    Science.gov (United States)

    Chambers, David W

    2008-01-01

    We all experience stress as a regular, and sometimes damaging and sometimes useful, part of our daily lives. In our normal ups and downs, we have our share of exhaustion, despondency, and outrage--matched with their corresponding positive moods. But burnout and workaholism are different. They are chronic, dysfunctional, self-reinforcing, life-shortening habits. Dentists, nurses, teachers, ministers, social workers, and entertainers are especially susceptible to burnout; not because they are hard-working professionals (they tend to be), but because they are caring perfectionists who share control for the success of what they do with others and perform under the scrutiny of their colleagues (they tend to). Workaholics are also trapped in self-sealing cycles, but the elements are ever-receding visions of control and using constant activity as a barrier against facing reality. This essay explores the symptoms, mechanisms, causes, and successful coping strategies for burnout and workaholism. It also takes a look at the general stress response on the physiological level and at some of the damage American society inflicts on itself.

  2. Meta-analysis of studies using suppression subtractive hybridization and microarrays to investigate the effects of environmental stress on gene transcription in oysters.

    Science.gov (United States)

    Anderson, Kelli; Taylor, Daisy A; Thompson, Emma L; Melwani, Aroon R; Nair, Sham V; Raftos, David A

    2015-01-01

    Many microarray and suppression subtractive hybridization (SSH) studies have analyzed the effects of environmental stress on gene transcription in marine species. However, there have been no unifying analyses of these data to identify common stress response pathways. To address this shortfall, we conducted a meta-analysis of 14 studies that investigated the effects of different environmental stressors on gene expression in oysters. The stressors tested included chemical contamination, hypoxia and infection, as well as extremes of temperature, pH and turbidity. We found that the expression of over 400 genes in a range of oyster species changed significantly after exposure to environmental stress. A repeating pattern was evident in these transcriptional responses, regardless of the type of stress applied. Many of the genes that responded to environmental stress encoded proteins involved in translation and protein processing (including molecular chaperones), the mitochondrial electron transport chain, anti-oxidant activity and the cytoskeleton. In light of these findings, we put forward a consensus model of sub-cellular stress responses in oysters.

  3. No effects of psychosocial stress on memory retrieval in non-treated young students with Generalized Social Phobia.

    Science.gov (United States)

    Espín, Laura; Marquina, Mónica; Hidalgo, Vanesa; Salvador, Alicia; Gómez-Amor, Jesús

    2016-11-01

    Generalized Social Phobia (GSP) is a common anxiety disorder that produces clear social life disruptions. There is no consensus on the specific processes involved in its development, but the role of the hypothalamic-pituitary-adrenal (HPA) axis has been suggested. This study analyzed the effects of the cortisol response to the Trier Social Stress Test (TSST) on the memory retrieval of pictures with different emotional valences in 45 non-treated young students with GSP and 50 non-anxious (NA) subjects (mean=19.35years, SD=0.18). No differences were found in the cortisol response of GSP and NA subjects to the TSST and control sessions. In addition, psychosocial stress impaired memory retrieval in both the GSP and NA groups, with no differences between them. Regarding the sex factor, no effects were found in the cortisol response to the TSST. However, during the encoding session, GSP men had higher cortisol levels than GSP women and NA subjects. There was also a significant interaction between sex and stress exposure on memory retrieval. Women recognized more unpleasant and neutral pictures than men; however, under stress, the women's advantage disappeared, and the men's performance improved. Sex also interacted with social phobia on positive mood, with GSP women exposed to the TSST showing the lowest positive mood. These results suggest that GSP subjects do not present an HPA axis sensitization to psychosocial stress, and they emphasize the importance of Sex in understanding stress effects on memory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The relationship between general health and coping style with the perceived stress in primigravida healthy pregnant women: using the PATH model.

    Science.gov (United States)

    Shamsaei, Farshid; Maleki, Azam; Shobeiri, Fatemeh; Soltani, Farzaneh; Ahmadi, Fazlollah; Roshanaei, Ghodratollah

    2018-02-05

    The aim of this study was to analyze relationships among general health, coping style, and perceived stress in healthy primigravida pregnant women. A cross-sectional study was conducted at public health clinics in Hamadan city, Iran between July and December 2015. In total, 380 pregnant women were selected through stratified random sampling. Data were collected using the Revised Prenatal Coping Inventory and General Health Questionnaire. Perceived stress was assessed through an interview comprised of open-ended questions. The final PATH model fit well; general health (β = 0.02) as well as anxiety and sleep disorders (β = 0.03) were slightly directly associated with perceived stress, and only planning-preparation was related to perceived stress through general health (β = 0.09). The findings enhance the knowledge gained from previous perinatal stress research. General health status was directly related to stress, and coping style was indirectly related to stress. Coping styles may mediate the relationship between general health status and perceived stress, suggesting that midwives should attempt to improve the general health of women to reduce stress and its consequences during pregnancy by teaching patients appropriate coping styles. Further studies on the effect of coping style interventions on stress are warranted.

  5. Unraveling uranium induced oxidative stress related responses in Arabidopsis thaliana seedlings. Part II: responses in the leaves and general conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Vanhoudt, Nathalie, E-mail: nvanhoud@sckcen.be [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Cuypers, Ann [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Horemans, Nele [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Remans, Tony; Opdenakker, Kelly; Smeets, Karen [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Bello, Daniel Martinez [Hasselt University, Interuniversity Institute for Biostatistics and Statistical Bioinformatics, Agoralaan Building D, 3590 Diepenbeek (Belgium); Havaux, Michel [Commissariat a l' Energie Atomique (CEA)/Cadarache, Direction des Sciences du Vivant, Departement d' Ecophysiologie Vegetale et de Microbiologie, Laboratoire d' Ecophysiologie de la Photosynthese, 13108 Saint-Paul-lez-Durance (France); Wannijn, Jean; Van Hees, May [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium); Vangronsveld, Jaco [Hasselt University, Environmental Biology, Centre for Environmental Sciences, Agoralaan Building D, 3590 Diepenbeek (Belgium); Vandenhove, Hildegarde [Belgian Nuclear Research Center (SCK-CEN), Biosphere Impact Studies, Boeretang 200, 2400 Mol (Belgium)

    2011-06-15

    The cellular redox balance seems an important modulator under heavy metal stress. While for other heavy metals these processes are well studied, oxidative stress related responses are also known to be triggered under uranium stress but information remains limited. This study aimed to further unravel the mechanisms by which plants respond to uranium stress. Seventeen-day-old Arabidopsis thaliana seedlings, grown on a modified Hoagland solution under controlled conditions, were exposed to 0, 0.1, 1, 10 and 100 {mu}M uranium for 1, 3 and 7 days. While in Part I of this study oxidative stress related responses in the roots were discussed, this second Part II discusses oxidative stress related responses in the leaves and general conclusions drawn from the results of the roots and the leaves will be presented. As several responses were already visible following 1 day exposure, when uranium concentrations in the leaves were negligible, a root-to-shoot signaling system was suggested in which plastids could be important sensing sites. While lipid peroxidation, based on the amount of thiobarbituric acid reactive compounds, was observed after exposure to 100 {mu}M uranium, affecting membrane structure and function, a transient concentration dependent response pattern was visible for lipoxygenase initiated lipid peroxidation. This transient character of uranium stress responses in leaves was emphasized by results of lipoxygenase (LOX2) and antioxidative enzyme transcript levels, enzyme capacities and glutathione concentrations both in time as with concentration. The ascorbate redox balance seemed an important modulator of uranium stress responses in the leaves as in addition to the previous transient responses, the total ascorbate concentration and ascorbate/dehydroascorbate redox balance increased in a concentration and time dependent manner. This could represent either a slow transient response or a stable increase with regard to plant acclimation to uranium stress

  6. General Space-Confined On-Substrate Fabrication of Thickness-Adjustable Hybrid Perovskite Single-Crystalline Thin Films.

    Science.gov (United States)

    Chen, Yao-Xuan; Ge, Qian-Qing; Shi, Yang; Liu, Jie; Xue, Ding-Jiang; Ma, Jing-Yuan; Ding, Jie; Yan, Hui-Juan; Hu, Jin-Song; Wan, Li-Jun

    2016-12-21

    Organic-inorganic hybrid perovskite single-crystalline thin films (SCTFs) are promising for enhancing photoelectric device performance due to high carrier mobility, long diffusion length, and carrier lifetime. However, bulk perovskite single crystals available today are not suitable for practical device application due to the unfavorable thickness. Herein, we report a facile space-confined solution-processed strategy to on-substrate grow various hybrid perovskite SCTFs in a size of submillimeter with adjustable thicknesses from nano- to micrometers. These SCTFs exhibit photoelectric properties comparable to bulk single crystals with low defect density and good air stability. The clear thickness-dependent colors allow fast visual selection of SCTFs with a suitable thickness for specific device application. The present substrate-independent growth of perovskite SCTFs opens up opportunities for on-chip fabrication of diverse high-performance devices.

  7. Axi-symmetric generalized thermoelastic diffusion problem with two-temperature and initial stress under fractional order heat conduction

    International Nuclear Information System (INIS)

    Deswal, Sunita; Kalkal, Kapil Kumar; Sheoran, Sandeep Singh

    2016-01-01

    A mathematical model of fractional order two-temperature generalized thermoelasticity with diffusion and initial stress is proposed to analyze the transient wave phenomenon in an infinite thermoelastic half-space. The governing equations are derived in cylindrical coordinates for a two dimensional axi-symmetric problem. The analytical solution is procured by employing the Laplace and Hankel transforms for time and space variables respectively. The solutions are investigated in detail for a time dependent heat source. By using numerical inversion method of integral transforms, we obtain the solutions for displacement, stress, temperature and diffusion fields in physical domain. Computations are carried out for copper material and displayed graphically. The effect of fractional order parameter, two-temperature parameter, diffusion, initial stress and time on the different thermoelastic and diffusion fields is analyzed on the basis of analytical and numerical results. Some special cases have also been deduced from the present investigation.

  8. Biomarkers of general stress in mussels as common indicators for marine biomonitoring programmes in Europe: The ICON experience.

    Science.gov (United States)

    Martínez-Gómez, Concepción; Robinson, Craig David; Burgeot, Thierry; Gubbins, Matt; Halldorsson, Halldor P; Albentosa, Marina; Bignell, John P; Hylland, Ketil; Vethaak, A Dick

    2017-03-01

    This study investigated whether general stress biomarkers in mussels can be applied as common first-tier biomarkers in regional biomonitoring programmes in the North Sea (including Iceland) and western Mediterranean Sea. Stress on Stress (SoS) and lysosomal membrane stability (LMS) biomarkers were analysed in resident mussels (Mytilus sp.) from 8 coastal sites and in transplanted mussels (Mytilus galloprovincialis) from two Spanish Mediterranean coastal sites. The assessment of results, as input to pollution monitoring strategies, was performed jointly for LMS and SoS data from the two regions. Contaminant body burden of the mussels was compared with biomarker results. The results demonstrated that these two general and non-expensive stress biomarkers in mussel can be applied throughout European waters, providing a cost-effective and harmonised approach to screen contaminant-related biological effects within the framework of wide-scale pollution biomonitoring programmes, such as that proposed by the European Union, i.e. the Marine Strategy Framework Directive. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Relationship between Maternal General and Specific-Pregnancy Stress, Anxiety, and Depression Symptoms and Pregnancy Outcome.

    Science.gov (United States)

    Hasanjanzadeh, Parvin; Faramarzi, Mahbobeh

    2017-04-01

    Despite scientific advances in the field of physical problems during pregnancy, the effect of mental problems on the health of pregnant women is still an important issue that needs further research. To determine the association of symptoms of stress, anxiety and depression during pregnancy and there effect on the pregnancy outcome. This was a descriptive correlational study. The population included 200 pregnant women of the urban and rural health centers affiliated with Babol University of Medical Sciences. There were 100 each in second and third trimester. Convenience multi stage cluster sampling was performed. Data collection was received through the Hospital Anxiety Depression Scale (HADS), Pregnancy Distress Questionnaire (PDQ), and Perceived Stress Scale (PSS-14) questionnaires. The correlation results showed a significant difference between variables of depression, stress, and anxiety with birth weight, birth height and head circumference and infants' APGAR score (prelationships on prediction of infant weight (B=-0.324), anxiety on prediction of infant height (B=-0.197), stress on prediction of head circumference (B=-0.350) and depression on prediction of APGAR score (B=-0.323) are effective (pdepression, anxiety and stress in pregnancy, and scheduling to avoid adverse consequences of the pregnancy outcome.

  10. The Brucella abortus virulence regulator, LovhK, is a sensor kinase in the general stress response signalling pathway.

    Science.gov (United States)

    Kim, Hye-Sook; Willett, Jonathan W; Jain-Gupta, Neeta; Fiebig, Aretha; Crosson, Sean

    2014-11-01

    In the intracellular pathogen Brucella abortus, the general stress response (GSR) signalling system determines survival under acute stress conditions in vitro, and is required for long-term residence in a mammalian host. To date, the identity of the Brucella sensor kinase(s) that function to perceive stress and directly activate GSR signalling have remained undefined. We demonstrate that the flavin-binding sensor histidine kinase, LovhK (bab2_0652), functions as a primary B. abortus GSR sensor. LovhK rapidly and specifically phosphorylates the central GSR regulator, PhyR, and activates transcription of a set of genes that closely overlaps the known B. abortus GSR regulon. Deletion of lovhK severely compromises cell survival under defined oxidative and acid stress conditions. We further show that lovhK is required for cell survival during the early phase of mammalian cell infection and for establishment of long-term residence in a mouse infection model. Finally, we present evidence that particular regions of primary structure within the two N-terminal PAS domains of LovhK have distinct sensory roles under specific environmental conditions. This study elucidates new molecular components of a conserved signalling pathway that regulates B. abortus stress physiology and infection biology. © 2014 John Wiley & Sons Ltd.

  11. Using a hybrid subtyping model to capture patterns and dimensionality of depressive and anxiety symptomatology in the general population.

    Science.gov (United States)

    Wardenaar, Klaas J; Wanders, Rob B K; Ten Have, Margreet; de Graaf, Ron; de Jonge, Peter

    2017-06-01

    Researchers have tried to identify more homogeneous subtypes of major depressive disorder (MDD) with latent class analyses (LCA). However, this approach does no justice to the dimensional nature of psychopathology. In addition, anxiety and functioning-levels have seldom been integrated in subtyping efforts. Therefore, this study used a hybrid discrete-dimensional approach to identify subgroups with shared patterns of depressive and anxiety symptomatology, while accounting for functioning-levels. The Comprehensive International Diagnostic Interview (CIDI) 1.1 was used to assess previous-year depressive and anxiety symptoms in the Netherlands Mental Health Survey and Incidence Study-1 (NEMESIS-1; n=5583). The data were analyzed with factor analyses, LCA and hybrid mixed-measurement item response theory (MM-IRT) with and without functioning covariates. Finally, the classes' predictors (measured one year earlier) and outcomes (measured two years later) were investigated. A 3-class MM-IRT model with functioning covariates best described the data and consisted of a 'healthy class' (74.2%) and two symptomatic classes ('sleep/energy' [13.4%]; 'mood/anhedonia' [12.4%]). Factors including older age, urbanicity, higher severity and presence of 1-year MDD predicted membership of either symptomatic class vs. the healthy class. Both symptomatic classes showed poorer 2-year outcomes (i.e. disorders, poor functioning) than the healthy class. The odds of MDD after two years were especially increased in the mood/anhedonia class. Symptoms were assessed for the past year whereas current functioning was assessed. Heterogeneity of depression and anxiety symptomatology are optimally captured by a hybrid discrete-dimensional subtyping model. Importantly, accounting for functioning-levels helps to capture clinically relevant interpersonal differences. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Modelling of fluid flow phenomenon in laser+GMAW hybrid welding of aluminum alloy considering three phase coupling and arc plasma shear stress

    Science.gov (United States)

    Xu, Guoxiang; Li, Pengfei; Cao, Qingnan; Hu, Qingxian; Gu, Xiaoyan; Du, Baoshuai

    2018-03-01

    The present study aims to develop a unified three dimensional numerical model for fiber laser+GMAW hybrid welding, which is used to study the fluid flow phenomena in hybrid welding of aluminum alloy and the influence of laser power on weld pool dynamic behavior. This model takes into account the coupling of gas, liquid and metal phases. Laser heat input is described using a cone heat source model with changing peak power density, its height being determined based on the keyhole size. Arc heat input is modeled as a double ellipsoid heat source. The arc plasma flow and droplet transfer are simulated through the two simplified models. The temperature and velocity fields for different laser powers are calculated. The computed results are in general agreement with the experimental data. Both the peak and average values of fluid flow velocity during hybrid welding are much higher than those of GMAW. At a low level of laser power, both the arc force and droplet impingement force play a relatively large role on fluid flow in the hybrid welding. Keyhole depth always oscillates within a range. With an increase in laser power, the weld pool behavior becomes more complex. An anti-clockwise vortex is generated and the stability of keyhole depth is improved. Besides, the effects of laser power on different driving forces of fluid flow in weld pool are also discussed.

  13. Stress

    Science.gov (United States)

    ... taking care of an aging parent. With mental stress, the body pumps out hormones to no avail. Neither fighting ... with type 1 diabetes. This difference makes sense. Stress blocks the body from releasing insulin in people with type 2 ...

  14. Investigation of marital satisfaction and its relationship with job stress and general health of nurses in Qazvin, Iran.

    Science.gov (United States)

    Azimian, Jalil; Piran, Pegah; Jahanihashemi, Hassan; Dehghankar, Leila

    2017-04-01

    Pressures in nursing can affect family life and marital problems, disrupt common social problems, increase work-family conflicts and endanger people's general health. To determine marital satisfaction and its relationship with job stress and general health of nurses. This descriptive and cross-sectional study was done in 2015 in medical educational centers of Qazvin by using an ENRICH marital satisfaction scale and General Health and Job Stress questionnaires completed by 123 nurses. Analysis was done by SPSS version 19 using descriptive and analytical statistics (Pearson correlation, t-test, ANOVA, Chi-square, regression line, multiple regression analysis). The findings showed that 64.4% of nurses had marital satisfaction. There was significant relationship between age (p=0.03), job experience (p=0.01), age of spouse (p=0.01) and marital satisfaction. The results showed that there was a significant relationship between marital satisfaction and general health (pstress and disorder in general health of nurses and low marital satisfaction by running health promotion programs and paying attention to its dimensions can help work and family health of nurses.

  15. Specificity and generalization of attentional bias in sexual trauma victims suffering from posttraumatic stress disorder

    NARCIS (Netherlands)

    Fleurkens, P.F.T.; Rinck, M.; Minnen, A. van

    2011-01-01

    The present study investigated specificity of attentional biases for trauma-related stimuli using an Emotional Stroop Task. Participants were 14 women suffering from posttraumatic stress disorder (PTSD) who had experienced a sexual trauma and 24 healthy non-traumatized women. They were asked to name

  16. Childhood Posttraumatic Stress Disorder: Diagnosis, Treatment, and School Reintegration. General Articles

    Science.gov (United States)

    Cook-Cottone, Catherine

    2004-01-01

    Childhood, in our culture, does not preclude exposure to trauma. Sexual abuse, physical abuse, natural disaster, urban violence, school violence, and terrorism result in significant numbers of children with posttraumatic stress disorder (PTSD) symptomatology. Many factors contribute to symptomatic expression, with some children showing few effects…

  17. Method for x-ray determination of three axial stresses of general orientation

    Energy Technology Data Exchange (ETDEWEB)

    Doelle, H; Hauk, V [Technische Hochschule Aachen (Germany, F.R.). Inst. fuer Werkstoffkunde; Juehe, H H; Krause, H [Technische Hochschule Aachen (Germany, F.R.). Lehrgebiet Abnutzung der Werkstoffe

    1976-11-01

    The authors describe a method of detecting three-dimensional self-stress/self-strain systems by means of X-ray measurements of the distances between the lattice planes in three directions of the sample surface. The method is illustrated by a study of a sample from a type of an electric railcar which had been deformed mainly by tangential forces.

  18. Oral manifestations of stress-related disorders in the general population of Ludhiana

    Directory of Open Access Journals (Sweden)

    Damanpreet Kaur

    2016-01-01

    Full Text Available Introduction: Oral diseases associated with psychological disorders have long been known in medicine. Emotional as well as psychological factors may act as significant risk factors in the initiation and progression of oromucosal diseases. Aims and Objectives: The aim of this study was to determine a correlation between stress and development of certain oral conditions such as lichen planus, myofacial pain dysfunction syndrome, xerostomia, bruxism, aphthous ulcers, and burning mouth syndrome. Materials and Methods: An observational comparative study was conducted among patients reporting to the Department of Oral Medicine and Radiology. A total of 130 patients gave a positive history of oral lesions, out of which 62 were stress related and the other 68 patients served as the control group (oral lesions with no history of stress. All these patients were subjected to routine systemic and oral examination. The results obtained were statistically compared using P value, t-test, and Chi-square test. Results: It was found that lichen planus and burning mouth syndrome were more common in females and myofacial pain dysfunction syndrome was prevalent in males. Xerostomia was found to increase with age. Conclusion: It was concluded that, though the etiology of most oral lesions is not known, the role of stress and other psychogenic factors cannot be ruled out in their occurrence.

  19. Stress-related mental disorders with sick leave: a minimal intervention in general practice

    NARCIS (Netherlands)

    Bakker, I.M.

    2007-01-01

    1. Introduction As stated in chapter 1, this study is carried out because patients and their care-givers have much to gain by the development and implementation of effective care for patients on sick leave having stress-related mental disorders (SMDs). Most people having SMDs with sick leave consult

  20. The Influence of Oral Carbohydrate Solution Intake on Stress Response before Total Hip Replacement Surgery during Epidural and General Anaesthesia.

    Science.gov (United States)

    Çeliksular, M Cem; Saraçoğlu, Ayten; Yentür, Ercüment

    2016-06-01

    The effects of oral carbohydrate solutions, ingested 2 h prior to operation, on stress response were studied in patients undergoing general or epidural anaesthesia. The study was performed on 80 ASA I-II adult patients undergoing elective total hip replacement, which were randomized to four groups (n=20). Group G patients undergoing general anaesthesia fasted for 8 h preoperatively; Group GN patients undergoing general anaesthesia drank oral carbohydrate solutions preoperatively; Group E patients undergoing epidural anaesthesia fasted for 8 h and Group EN patients undergoing epidural anaesthesia drank oral carbohydrate solutions preoperatively. Groups GN and EN drank 800 mL of 12.5% oral carbohydrate solution at 24:00 preoperatively and 400 mL 2 h before the operation. Blood samples were taken for measurements of glucose, insulin, cortisol and IL-6 levels. The effect of preoperative oral carbohydrate ingestion on blood glucose levels was not significant. Insulin levels 24 h prior to surgery were similar; however, insulin levels measured just before surgery were 2-3 times higher in groups GN and EN than in groups G and E. Insulin levels at the 24(th) postoperative hour in epidural groups were increased compared to those at basal levels, although general anaesthesia groups showed a decrease. From these measurements, only the change in Group EN was statistically significant (poral carbohydrate nutrition did not reveal a significant effect on surgical stress response.

  1. Evaluation of Turf-type Interspecific Hybrids of Meadow Fescue with Perennial Ryegrass for Improved Stress Tolerance

    Czech Academy of Sciences Publication Activity Database

    Barnes, B.D.; Kopecký, David; Lukaszewski, A.J.; Baird, J. H.

    2014-01-01

    Roč. 54, č. 1 (2014), s. 355-365 ISSN 0011-183X R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : LOLIUM-FESTUCA COMPLEX * TALL FESCUE * INTERGENERIC HYBRIDS Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.575, year: 2014

  2. The Role of Generalized Explicit and Implicit Guilt and Shame in Interpersonal Traumatization and Posttraumatic Stress Disorder.

    Science.gov (United States)

    Bockers, Estelle; Roepke, Stefan; Michael, Lars; Renneberg, Babette; Knaevelsrud, Christine

    2016-02-01

    Posttraumatic stress disorder (PTSD) and interpersonal traumatization are frequently associated with trauma-related guilt and shame. However, research on generalized guilt and shame in PTSD is lacking. The aim of this study was to investigate generalized explicit and implicit guilt and shame in interpersonal traumatization and PTSD. Interpersonally traumatized women either with PTSD (n = 28) or without PTSD (n = 32) and 32 nontraumatized women completed the Test of Self-Conscious Affect-3 and the Implicit Association Test to measure explicit and implicit guilt and shame. Explicit guilt and shame were significantly higher in women with PTSD than in traumatized women without PTSD. Traumatized women without PTSD showed significantly higher levels of explicit guilt and shame than nontraumatized women did. PTSD was associated with implicit guilt but not implicit shame. In addition to trauma-related guilt and shame, generalized explicit guilt and shame and implicit guilt seem to play a crucial role in PTSD.

  3. Spa therapy (balneotherapy) relieves mental stress, sleep disorder, and general health problems in sub-healthy people

    Science.gov (United States)

    Yang, Bei; Qin, Qi-zhong; Han, Ling-li; Lin, Jing; Chen, Yu

    2018-02-01

    To investigate the relieving effects of hot spring balneotherapy on mental stress, sleep disorder, general health problems, and women's health problems in sub-healthy people, we recruited 500 volunteers in sub-health in Chongqing, and 362 volunteers completed the project, including 223 in the intervention group and 139 in the control group. The intervention group underwent hot spring balneotherapy for 5 months, while the control group did not. The two groups took questionnaire investigation (general data, mental stress, emotional status, sleep quality, general health problems, as well as some women's health problems) and physical examination (height, weight, waist circumference, blood pressure, blood lipid, blood sugar) 5 months before and after the intervention, respectively. After intervention, sleep disorder (difficulty in falling asleep ( P = 0.017); dreaminess, nightmare suffering, and restless sleep ( P = 0.013); easy awakening ( P = 0.003) and difficulty in falling into sleep again after awakening( P = 0.016); and mental stress ( P = 0.031) and problems of general health (head pain ( P = 0.026), joint pain( P = 0.009), leg or foot cramps ( P = 0.001), blurred vision ( P = 0.009)) were relieved significantly in the intervention group, as compared with the control group. While other indicators (fatigue, eye tiredness, limb numbness, constipation, skin allergy) and women's health problems (breast distending pain; dysmenorrhea, irregular menstruation) were relieved significantly in the self-comparison of the intervention group before and after intervention ( P 0.05). All indications (except bad mood, low mood, and worry or irritability) in the intervention group significantly improved, with effect size from 0.096 to 1.302. Multiple logistic regression analysis showed that the frequency, length, and location of balneotherapy in the intervention group were the factors influencing emotion, sleep, and health condition ( P Physical examination found that waist

  4. Comparison of Welding Residual Stresses of Hybrid Laser-Arc Welding and Submerged Arc Welding in Offshore Steel Structures

    DEFF Research Database (Denmark)

    Andreassen, Michael Joachim; Yu, Zhenzhen; Liu, Stephen

    2016-01-01

    In the offshore industry, welding-induced distortion and tensile residual stresses have become a major concern in relation to the structural integrity of a welded structure. Particularly, the continuous increase in size of welded plates and joints needs special attention concerning welding induced...... residual stresses. These stresses have a negative impact on the integrity of the welded joint as they promote distortion, reduce fatigue life, and contribute to corrosion cracking and premature failure in the weld components. This paper deals with the influence and impact of welding method on the welding...... induced residual stresses. It is also investigated whether the assumption of residual stresses up to yield strength magnitude are present in welded structures as stated in the design guidelines. The fatigue strength for welded joints is based on this assumption. The two welding methods investigated...

  5. General optimization procedure towards the design of a new family of minimal parameter spin-component-scaled double-hybrid density functional theory.

    Science.gov (United States)

    Roch, Loïc M; Baldridge, Kim K

    2017-10-04

    A general optimization procedure towards the development and implementation of a new family of minimal parameter spin-component-scaled double-hybrid (mSD) density functional theory (DFT) is presented. The nature of the proposed exchange-correlation functional establishes a methodology with minimal empiricism. This new family of double-hybrid (DH) density functionals is demonstrated using the PBEPBE functional, illustrating the optimization procedure to the mSD-PBEPBE method, and the performance characteristics shown for a set of non-covalent complexes covering a broad regime of weak interactions. With only two parameters, mSD-PBEPBE and its cost-effective counterpart, RI-mSD-PBEPBE, show a mean absolute error of ca. 0.4 kcal mol -1 averaged over 66 weak interacting systems. Following a successive 2D-grid refinement for a CBS extrapolation of the coefficients, the optimization procedure can be recommended for the design and implementation of a variety of additional DH methods using any of the plethora of currently available functionals.

  6. Awake craniotomy for cortical language mapping and resection of an arteriovenous malformation adjacent to eloquent areas under general anesthesia — A hybrid approach

    Directory of Open Access Journals (Sweden)

    Pree Nimmannitya

    2015-12-01

    Full Text Available Surgery of arteriovenous malformation (AVM is sometimes challenging and carries a high risk of morbidity, especially when the AVM is located in an eloquent area of the brain. Unlike gliomas, awake craniotomy has not been widely used for resection of AVM. The authors present a case of an AVM in the left frontal lobe which was successfully removed with the aid of awake craniotomy with cortical language mapping. In conclusion, awake craniotomy for functional cortical mapping is beneficial for AVM resection, especially when the lesion is located in or adjacent to eloquent areas of the brain. A hybrid approach with functional mapping in the awake condition and AVM resection under general anesthesia may be useful in selected cases. Furthermore, en bloc resection with the nidus embedded in the brain parenchyma may be a useful means of removal to reduce operation time and intraoperative blood loss if there is no apparent functional cortex surrounding the AVM, as in the present case.

  7. Effect of aging on the general corrosion and stress corrosion cracking of uranium--6 wt % niobium alloy

    International Nuclear Information System (INIS)

    Koger, J.W.; Ammons, A.M.; Ferguson, J.E.

    1975-11-01

    Mechanical properties of the uranium-6 wt percent niobium alloy change with aging time and temperature. In general, the ultimate tensile strength and hardness reach a peak, while elongation becomes a minimum at aging temperatures between 400 and 500 0 C. The first optical evidence of a second phase was in the 400 0 C-aged alloy, while complete transformation to a two-phase structure was seen in the 600 0 C-aged alloy. The maximum-strength conditions correlate with the minimum stress corrosion cracking (SCC) resistance. The maximum SCC resistance is found in the as-quenched and 150, 200, and 600 0 C-aged specimens. The as-quenched and 300 0 C-aged specimens had the greatest resistance to general corrosion in aqueous chloride solutions; the 600 0 C-aged specimen had the least resistance

  8. The Effects of General and Epidural Anaesthesia in Maternal’s Stress Hormones and Blood Gases in Elective Cesarean Section

    Directory of Open Access Journals (Sweden)

    Meral EZBERCI

    2005-09-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the effects of general and epidural anaesthesia in maternal’s stress hormones and blood gases in elective cesarean section.\tMATERIALS-METHODS: 50 patients in ASA II (American Society of Anesthesiology class who would undergo elective cesarean section in University of Kahramanmaras Sutcuimam, Department of Anaesthesiology and Reanimation included in the study and randomized into two equal groups (General anaesthesia: Group G and Epidural anaesthesia: Group E. In both groups, maternal stress hormones (TSH, cortisol, and insulin and blood gases were studied. All patients received famotidine and granisetron iv 30 min before operations in premedication room. In the general anaesthesia group; aritmal, propofol, and succinylcholine was used for induction and muscle relaxation. Following the induction, positive pressure ventilation of the lungs was started immediately using a 50% N2O + O2 mixture. After delivery of the baby, anaesthesia and muscle relaxation was maintained by 50% N2O +O2, 0,5-1% MAC isoflurane, and cisatracurium. In the epidural anaesthesia group; epidural anaesthesia was performed with 0,375 % bupivacaine. The epidural needle inserted through L2-3 or L3-4 interspace. After achieving T4-5 neural blockade, the operation was started. In general anaesthesia group; blood samples for maternal stres hormones were taken before induction and after delivery of the baby. In epidural anaesthesia group; blood samples for maternal stres hormones were taken catheter placement and after delivery of the baby. Blood samples for maternal blood gases were taken after the delivery of the baby.\tRESULTS: In both groups; there were statistically significant decrease in maternal TSH and insulin and there were no statistically significant changes in maternal cortisol. In maternal blood gases analyses, only PO2 and SO2 changes were statistically significant between two groups.\tCONCLUSION: With these results

  9. Boron Stress Activates the General Amino Acid Control Mechanism and Inhibits Protein Synthesis

    Science.gov (United States)

    Uluisik, Irem; Kaya, Alaattin; Fomenko, Dmitri E.; Karakaya, Huseyin C.; Carlson, Bradley A.; Gladyshev, Vadim N.; Koc, Ahmet

    2011-01-01

    Boron is an essential micronutrient for plants, and it is beneficial for animals. However, at high concentrations boron is toxic to cells although the mechanism of this toxicity is not known. Atr1 has recently been identified as a boron efflux pump whose expression is upregulated in response to boron treatment. Here, we found that the expression of ATR1 is associated with expression of genes involved in amino acid biosynthesis. These mechanisms are strictly controlled by the transcription factor Gcn4 in response to boron treatment. Further analyses have shown that boron impaired protein synthesis by promoting phosphorylation of eIF2α in a Gcn2 kinase dependent manner. The uncharged tRNA binding domain (HisRS) of Gcn2 is necessary for the phosphorylation of eIF2α in the presence of boron. We postulate that boron exerts its toxic effect through activation of the general amino acid control system and inhibition of protein synthesis. Since the general amino acid control pathway is conserved among eukaryotes, this mechanism of boron toxicity may be of general importance. PMID:22114689

  10. Boron stress activates the general amino acid control mechanism and inhibits protein synthesis.

    Directory of Open Access Journals (Sweden)

    Irem Uluisik

    Full Text Available Boron is an essential micronutrient for plants, and it is beneficial for animals. However, at high concentrations boron is toxic to cells although the mechanism of this toxicity is not known. Atr1 has recently been identified as a boron efflux pump whose expression is upregulated in response to boron treatment. Here, we found that the expression of ATR1 is associated with expression of genes involved in amino acid biosynthesis. These mechanisms are strictly controlled by the transcription factor Gcn4 in response to boron treatment. Further analyses have shown that boron impaired protein synthesis by promoting phosphorylation of eIF2α in a Gcn2 kinase dependent manner. The uncharged tRNA binding domain (HisRS of Gcn2 is necessary for the phosphorylation of eIF2α in the presence of boron. We postulate that boron exerts its toxic effect through activation of the general amino acid control system and inhibition of protein synthesis. Since the general amino acid control pathway is conserved among eukaryotes, this mechanism of boron toxicity may be of general importance.

  11. Stress

    DEFF Research Database (Denmark)

    Keller, Hanne Dauer

    2015-01-01

    Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb.......Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb....

  12. Stress !!!

    OpenAIRE

    Fledderus, M.

    2012-01-01

    Twee op de vijf UT-studenten hebben last van ernstige studiestress, zo erg zelfs dat het ze in hun privéleven belemmert. Die cijfers komen overeen met het landelijk beeld van stress onder studenten. Samen met 14 andere universiteits- en hogeschoolbladen enquêteerde UT Nieuws bijna 5500 studenten. Opvallend is dat mannelijke studenten uit Twente zich veel minder druk lijken te maken over hun studie. Onder vrouwen ligt de stress juist erg hoog ten opzichte van het landelijk gemiddelde.

  13. Determinants of the development of post-traumatic stress disorder, in the general population.

    Science.gov (United States)

    Perrin, Marc; Vandeleur, Caroline L; Castelao, Enrique; Rothen, Stéphane; Glaus, Jennifer; Vollenweider, Peter; Preisig, Martin

    2014-03-01

    To assess (1) the lifetime prevalence of exposure both to trauma and post-traumatic stress disorder (PTSD); (2) the risk of PTSD by type of trauma; and (3) the determinants of the development of PTSD in the community. The Diagnostic Interview for Genetic Studies was administered to a random sample of an urban area (N = 3,691). (1) The lifetime prevalence estimates of exposure to trauma and PTSD were 21.0 and 5.0%; respectively, with a twice as high prevalence of PTSD in women compared to men despite a similar likelihood of exposure in the two sexes; (2) Sexual abuse was the trauma involving the highest risk of PTSD; (3) The risk of PTSD was most strongly associated with sexual abuse followed by preexisting bipolar disorder, alcohol dependence, antisocial personality, childhood separation anxiety disorder, being victim of crime, witnessing violence, Neuroticism and Problem-focused coping strategies. After adjustment for these characteristics, female sex was no longer found to be significantly associated with the risk of PTSD. The risk for the development of PTSD after exposure to traumatic events is associated with several factors including the type of exposure, preexisting psychopathology, personality features and coping strategies which independently contribute to the vulnerability to PTSD.

  14. Pathways from assaultive violence to post-traumatic stress, depression, and generalized anxiety symptoms through stressful life events: longitudinal mediation models.

    Science.gov (United States)

    Lowe, S R; Joshi, S; Galea, S; Aiello, A E; Uddin, M; Koenen, K C; Cerdá, M

    2017-10-01

    Assaultive violence events are associated with increased risk for adverse psychiatric outcomes, including post-traumatic stress (PTS), depression, and generalized anxiety. Prior research has indicated that economic, legal, and social stressors that could follow assaultive events may explain the increased risk for adverse psychiatric outcomes, yet longitudinal studies have not adequately examined this pathway. In the current study, we aimed to address this limitation. Participants (N = 1360) were part of a longitudinal population-based study of adults living in Detroit. At three waves, participants indicated their exposure to assaultive violence and economic, legal, and social stressors, and completed inventories of PTS, depression, and generalized anxiety. Longitudinal mediation models were used to test the hypothesized pathway from assaultive violence to each psychiatric outcome. The hypothesized models evidenced good fit with the data and, in each, the paths from Wave 1 (W1) assaultive violence to W2 stressors, and from W2 stressors to W3 symptoms were significant (range of Standardized Estimates: 0.09-0.15, all p violence to W3 symptoms were significant (range of Standardized Estimates: 0.01-0.02, all p violence increase risk for a range of psychiatric symptoms. Although future research is needed, the results suggest that investment in interventions that prevent and mitigate assaultive violence survivors' exposure to such stressors may be an effective way to prevent mental illness in the aftermath of violent assaults.

  15. Use of generalized regression models for the analysis of stress-rupture data

    International Nuclear Information System (INIS)

    Booker, M.K.

    1978-01-01

    The design of components for operation in an elevated-temperature environment often requires a detailed consideration of the creep and creep-rupture properties of the construction materials involved. Techniques for the analysis and extrapolation of creep data have been widely discussed. The paper presents a generalized regression approach to the analysis of such data. This approach has been applied to multiple heat data sets for types 304 and 316 austenitic stainless steel, ferritic 2 1 / 4 Cr-1 Mo steel, and the high-nickel austenitic alloy 800H. Analyses of data for single heats of several materials are also presented. All results appear good. The techniques presented represent a simple yet flexible and powerful means for the analysis and extrapolation of creep and creep-rupture data

  16. WrpA Is an Atypical Flavodoxin Family Protein under Regulatory Control of the Brucella abortus General Stress Response System.

    Science.gov (United States)

    Herrou, Julien; Czyż, Daniel M; Willett, Jonathan W; Kim, Hye-Sook; Chhor, Gekleng; Babnigg, Gyorgy; Kim, Youngchang; Crosson, Sean

    2016-04-01

    The general stress response (GSR) system of the intracellular pathogen Brucella abortus controls the transcription of approximately 100 genes in response to a range of stress cues. The core genetic regulatory components of the GSR are required for B. abortus survival under nonoptimal growth conditions in vitro and for maintenance of chronic infection in an in vivo mouse model. The functions of the majority of the genes in the GSR transcriptional regulon remain undefined. bab1_1070 is among the most highly regulated genes in this regulon: its transcription is activated 20- to 30-fold by the GSR system under oxidative conditions in vitro. We have solved crystal structures of Bab1_1070 and demonstrate that it forms a homotetrameric complex that resembles those of WrbA-type NADH:quinone oxidoreductases, which are members of the flavodoxin protein family. However, B. abortus WrbA-related protein (WrpA) does not bind flavin cofactors with a high affinity and does not function as an NADH:quinone oxidoreductase in vitro. Soaking crystals with flavin mononucleotide (FMN) revealed a likely low-affinity binding site adjacent to the canonical WrbA flavin binding site. Deletion of wrpA (ΔwrpA) does not compromise cell survival under acute oxidative stress in vitro or attenuate infection in cell-based or mouse models. However, a ΔwrpA strain does elicit increased splenomegaly in a mouse model, suggesting that WrpA modulates B. abortus interaction with its mammalian host. Despite high structural homology with canonical WrbA proteins, we propose that B. abortus WrpA represents a functionally distinct member of the diverse flavodoxin family. Brucella abortus is an etiological agent of brucellosis, which is among the most common zoonotic diseases worldwide. The general stress response (GSR) regulatory system of B. abortus controls the transcription of approximately 100 genes and is required for maintenance of chronic infection in a murine model; the majority of GSR-regulated genes

  17. GENERAL AND SPECIFIC COMBINING ABILITY OF INITIAL PARENTAL FORMS IN TOMATO FOR COMPLEX OF ECONOMICALLY VALUABLE TRAITS TO DEVELOP HYBRIDS F1 OF CHERRY AND COCKTAIL TYPES

    Directory of Open Access Journals (Sweden)

    R. K. Rechets

    2017-01-01

    Full Text Available Results of estimation of general and specific combining ability of male and female parental tomato forms were given for complex of traits. The estimation was carried out according to incomplete diallel crosses 15x15. Such varities   as   ‘Trapeza’,  Rosovaya  kapelka’,  ‘Seniorita’, ‘Ocharovanie’,  ‘Tigris’   ‘Vishnya  Zheltaya’  (Gavrish, ‘Denezhnoye Derevo’ (national breeding, and  lines: ‘46/06’,  ‘49/09’,  ‘295/09’,  ‘336/11’,  ‘354/11’,  ‘357/11’, ‘388/09’ (nor, ‘498’ (selection of TARI were used as intial breeding accessions, differing in bush type (determinate and indeterminate, duration of vegetative phase (ultraearly,  early, medium early, middle-ripening, fruit  shape (rounded, oval, fruit color (red, pink, black, orange, tiger and with the gene nor, fruit weight (10 g. and more, brush structure (dense, friable. As a results, ‘Trapeza’, ‘Vishnya Zheltaya’, ‘Ocharovaniye’, ‘Seniorita’, and lines: ‘295/10’, ‘49/09’,  ‘498’,  ‘357/11’,  ‘354/11’,  ‘388/09’  (nor were selected and recommended to be used in breeding program for development of heterotic hybrids with high fruit setting and generative bush type. The promising hybrids F1 with high constants of specific combining ability for a complex of economically valuable traits have been observed. Because of different lines and accessions were used in crossings, these hybrids varied in internode length of cluster type, classical or shorten; rounded or oval fruit shape; fruit  color, red (F1   combinations ‘354/11’ х ‘Seniorita’, ‘Trapeza’ х  ‘L.49/09’,  L.  ‘49/09’  х  L.354/11, pink (F1 combination ‘Rosovaya Kapelka’ х ‘L.354/11’, yellow (F1 combination ‘Ocharovaniye’ х  ‘Vishiya Zheltaya’, deep brown (F1 combination  ‘L.357/11’ х ‘L.354/11’.

  18. [Emotional stress as a clinical model to study the pathogenesis of the initial phase of the general adaptation syndrome].

    Science.gov (United States)

    Anikhovskaya, I A; Dvoenosov, V G; Zhdanov, R I; Koubatiev, A A; Mayskiy, I A; Markelova, M M; Meshkov, M V; Oparina, O N; Salakhov, I M; Yakovlev, M Yu

    2015-01-01

    General adaptation syndrome (GAS), the basis of the development of which is stress phenomenon, is an essential component of the pathogenesis of many diseases and syndromes. However, the patho genesis of GAS hitherto is considered exclusively from the endocrinological viewpoint. This relates primarily to the initial phase of the GAS, a clinical model for the study of which may be psycho-emotional stress (PES), which we studied using three groups of volunteers. The first one consists of 25 students who were waiting for unaccustomed physical activity (17 men) and play debut on the stage (8 women). The second group consists of 48 children (2-14 years) who expected for "planned" surgery. The third group of volunteers is made up of 80 students (41 women and 39 men) during the first exam. The concentration of cortisol, endotoxin (ET), the activity of antiendotoxin immunity (AEI) and the haemostatic system parameters were determined in the blood serum of volunteers in various combinations. We found laboratory evidence for PES at 92% of students of the first group, 58% of children of the second one and in 21% of students of the third group of volunteers (mostly women). The concentration of ET increased at 13 (52%) volunteers of the first group with a significant increase of average indicators in the whole group (from 0.84 ± 0.06 to 1.19 ± 0.04 EU/ml). At children of the second group, the average concentration of ET increased even more significantly (from 0.42 ± 0.02 to 1.63 ± 0.11 EU/ml), which was accompanied by the activation of the hemostasis system. A degree of the activation was directly dependent on the level of ET in the general circulation and on an activity of AEI. Examination stress in the third group of volunteers is accompanied by activation of plasma hemostasis (increased initial thrombosis rate and reduced the time it starts, lag-period) in 26% of female students and 15% of male students. We suggest that it is possible to use the PES as a clinical model

  19. Group X hybrid histidine kinase Chk1 is dispensable for stress adaptation, host-pathogen interactions and virulence in the opportunistic yeast Candida guilliermondii.

    Science.gov (United States)

    Navarro-Arias, María J; Dementhon, Karine; Defosse, Tatiana A; Foureau, Emilien; Courdavault, Vincent; Clastre, Marc; Le Gal, Solène; Nevez, Gilles; Le Govic, Yohann; Bouchara, Jean-Philippe; Giglioli-Guivarc'h, Nathalie; Noël, Thierry; Mora-Montes, Hector M; Papon, Nicolas

    2017-09-01

    Hybrid histidine kinases (HHKs) progressively emerge as prominent sensing proteins in the fungal kingdom and as ideal targets for future therapeutics. The group X HHK is of major interest, since it was demonstrated to play an important role in stress adaptation, host-pathogen interactions and virulence in some yeast and mold models, and particularly Chk1, that corresponds to the sole group X HHK in Candida albicans. In the present work, we investigated the role of Chk1 in the low-virulence species Candida guilliermondii, in order to gain insight into putative conservation of the role of group X HHK in opportunistic yeasts. We demonstrated that disruption of the corresponding gene CHK1 does not influence growth, stress tolerance, drug susceptibility, protein glycosylation or cell wall composition in C. guilliermondii. In addition, we showed that loss of CHK1 does not affect C. guilliermondii ability to interact with macrophages and to stimulate cytokine production by human peripheral blood mononuclear cells. Finally, the C. guilliermondii chk1 null mutant was found to be as virulent as the wild-type strain in the experimental model Galleria mellonella. Taken together, our results demonstrate that group X HHK function is not conserved in Candida species. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  20. Stress !!!

    NARCIS (Netherlands)

    Fledderus, M.

    2012-01-01

    Twee op de vijf UT-studenten hebben last van ernstige studiestress, zo erg zelfs dat het ze in hun privéleven belemmert. Die cijfers komen overeen met het landelijk beeld van stress onder studenten. Samen met 14 andere universiteits- en hogeschoolbladen enquêteerde UT Nieuws bijna 5500 studenten.

  1. Experiences of possession and paranormal phenomena among women in the general population: are they related to traumatic stress and dissociation?

    Science.gov (United States)

    Sar, Vedat; Alioğlu, Firdevs; Akyüz, Gamze

    2014-01-01

    This study sought to determine the prevalence of experiences of possession and paranormal phenomena (PNP) in the general population and their possible relations to each other and to traumatic stress and dissociation. The study was conducted on a representative female sample recruited from a town in central eastern Turkey. The Dissociative Disorders Interview Schedule, the posttraumatic stress disorder (PTSD) and borderline personality disorder sections of the Structured Clinical Interviews for DSM-IV Axis-I and Personality Disorders, and the Childhood Abuse and Neglect Questionnaire were administered to 628 women. Of these, 127 (20.2%) women reported at least 1 type of PNP and 13 (2.1%) women reported possession. Women with a dissociative disorder reported all types of possession and PNP (except telepathy) more frequently than those without. Whereas women with a trauma history in childhood and adulthood or PTSD reported possession more frequently than those without, PNP were associated with childhood trauma only. Factor analysis yielded 4 dimensions: possession by and/or contact with nonhuman entities, extrasensory communications, possession by a human entity, and precognition. These factors correlated with number of secondary features of dissociative identity disorder and Schneiderian symptoms. Latent class analysis identified 3 groups. The most traumatized group, with predominantly dissociative and trauma-related disorders, had the highest scores on all factors. Notwithstanding their presence in healthy individuals, possession and PNP were associated with trauma and dissociation in a subgroup of affected participants. Both types of experience seem to be normal human capacities of experiencing that may be involved in response to traumatic stress. Given the small numbers, this study should be considered preliminary.

  2. Association of Body Mass Index with Suicide Behaviors, Perceived Stress, and Life Dissatisfaction in the Korean General Population.

    Science.gov (United States)

    Kim, Haesoo; Jeon, Hong Jin; Bae, Jae Nam; Cho, Maeng Je; Cho, Seong Jin; Lee, Hyochul; Hong, Jin Pyo

    2018-03-01

    The purpose of the present study was to investigate the association between Body Mass Index, suicide, perceived stress, and life dissatisfaction in a general population sample of Korean adults. A total of 6,022 nationally representative adults aged 18 to 74 were selected using a multistage cross-sectional cluster sampling method. Questionnaires regarding suicide behaviors, perceived stress, and life satisfaction were completed by the participants. They also reported their heights and weights, which were used to calculate BMI. Psychiatric disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, using the Korean version of the Composite International Diagnostic Interview. The results showed that being underweight was associated with higher risk for suicide ideation [odds ratio (OR), 1.6; 95% confidence interval (Cl), 1.18-2.05] and suicide attempt (OR, 2.0, 95% Cl, 1.23-3.31). Likewise, obesity also increased the risk of suicide ideation (OR, 1.3; 95% Cl, 1.11-1.56) although not suicide attempt. Furthermore, underweight individuals were more likely to report severe level of perceived stress (OR, 1.7; 95% Cl, 1.26-2.17) and life dissatisfaction (OR, 1.3; 95% Cl, 1.07-1.68). All of the results remained significant after adjusting for age, gender, education, and psychiatric illnesses. This study found that being underweight is a significant risk factor for suicide and poor subjective wellbeing in Korea. It suggests that BMI status may be an important modifiable factor for improving mental health in Korea.

  3. A longitudinal study of posttraumatic stress disorder, depression, and generalized anxiety disorder in Israeli civilians exposed to war trauma.

    Science.gov (United States)

    Neria, Yuval; Besser, Avi; Kiper, Dasha; Westphal, Maren

    2010-06-01

    This 3-wave longitudinal study examined the mental health consequences of the Israel-Gaza 2008-2009 war among young Israeli civilians. Data on posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD), and their predictors were collected during the war, and 2 and 4 months after cease fire. Results showed a sharp decline in symptom levels of PTSD, MDD, and GAD over time. Perceived social support during the war moderated the effects of immediate emotional response on subsequent levels of PTSD, MDD, and GAD. These findings underscore the importance of social support and immediate emotional response to trauma in predicting trauma-related psychopathology, and highlight the potential need for providing early care to exposed individuals exhibiting immediate and severe emotional responses.

  4. A tailored relocation stress intervention programme for family caregivers of patients transferred from a surgical intensive care unit to a general ward.

    Science.gov (United States)

    Lee, Seul; Oh, HyunSoo; Suh, YeonOk; Seo, WhaSook

    2017-03-01

    To develop and examine a relocation stress intervention programme tailored for the family caregivers of patients scheduled for transfer from a surgical intensive care unit to a general ward. Family relocation stress syndrome has been reported to be similar to that exhibited by patients, and investigators have emphasised that nurses should make special efforts to relieve family relocation stress to maximise positive contributions to the well-being of patients by family caregivers. A nonequivalent control group, nonsynchronised pretest-post-test design was adopted. The study subjects were 60 family caregivers of patients with neurosurgical or general surgical conditions in the surgical intensive care unit of a university hospital located in Incheon, South Korea. Relocation stress and family burden were evaluated at three times, that is before intervention, immediately after transfer and four to five days after transfer. This relocation stress intervention programme was developed for the family caregivers based on disease characteristics and relocation-related needs. In the experimental group, relocation stress levels significantly and continuously decreased after intervention, whereas in the control group, a slight nonsignificant trend was observed. Family burden levels in the control group increased significantly after transfer, whereas burden levels in the experimental group increased only marginally and nonsignificantly. No significant between-group differences in relocation stress or family burden levels were observed after intervention. Relocation stress levels of family caregivers were significantly decreased after intervention in the experimental group, which indicates that the devised family relocation stress intervention programme effectively alleviated family relocation stress. The devised intervention programme, which was tailored to disease characteristics and relocation-related needs, may enhance the practicality and efficacy of relocation stress

  5. Associations among depressive symptoms, childhood abuse, neuroticism, and adult stressful life events in the general adult population

    Directory of Open Access Journals (Sweden)

    Ono K

    2017-02-01

    Full Text Available Kotaro Ono,1 Yoshikazu Takaesu,1 Yukiei Nakai,2 Akiyoshi Shimura,1 Yasuyuki Ono,1 Akiko Murakoshi,1 Yasunori Matsumoto,1 Hajime Tanabe,3 Ichiro Kusumi,2 Takeshi Inoue1 1Department of Psychiatry, Tokyo Medical University, Tokyo, 2Department of Psychiatry, Hokkaido University Graduate School of Medicine, Hokkaido, 3Department of Clinical Human Sciences, Graduate school of Humanities and Social Sciences, Shizuoka University, Shizuoka, Japan Background: Recent studies have suggested that the interactions among several factors affect the onset, progression, and prognosis of major depressive disorder. This study investigated how childhood abuse, neuroticism, and adult stressful life events interact with one another and affect depressive symptoms in the general adult population. Subjects and methods: A total of 413 participants from the nonclinical general adult population completed the Patient Health Questionnaire-9, the Child Abuse and Trauma Scale, the neuroticism subscale of the shortened Eysenck Personality Questionnaire – Revised, and the Life Experiences Survey, which are self-report scales. Structural equation modeling (Mplus version 7.3 and single and multiple regressions were used to analyze the data. Results: Childhood abuse, neuroticism, and negative evaluation of life events increased the severity of the depressive symptoms directly. Childhood abuse also indirectly increased the negative appraisal of life events and the severity of the depressive symptoms through enhanced neuroticism in the structural equation modeling. Limitations: There was recall bias in this study. The causal relationship was not clear because this study was conducted using a cross-sectional design. Conclusion: This study suggested that neuroticism is the mediating factor for the two effects of childhood abuse on adulthood depressive symptoms and negative evaluation of life events. Childhood abuse directly and indirectly predicted the severity of depressive symptoms

  6. Diabetes-Specific and General Life Stress and Glycemic Outcomes in Emerging Adults With Type 1 Diabetes: Is Race/Ethnicity a Moderator?

    Science.gov (United States)

    Butler, Ashley M; Weller, Bridget E; Yi-Frazier, Joyce P; Fegan-Bohm, Kelly; Anderson, Barbara; Pihoker, Catherine; Hilliard, Marisa E

    2017-10-01

    This study examines whether race/ethnicity moderates relationships of (a) diabetes stress and general life stressors with (b) diabetes outcomes of glycemic control and diabetic ketoacidosis (DKA) among emerging adults (aged 18-25 years) with type 1 diabetes (T1D). Using a T1D Exchange Registry sample of non-Hispanic White, African American, and Hispanic emerging adults (N = 3,440), multiple group analyses were used to determine whether race/ethnicity moderates the relationships between stress and diabetes outcomes. The relationships between the two stress types and glycemic control did not differ between African American and non-Hispanic Whites. However, as compared with non-Hispanic Whites, the association between higher diabetes-specific stress and poorer glycemic control was significantly stronger for Hispanics, and Hispanics had poorer glycemic control when they experienced a relatively fewer number of general life stressors than non-Hispanic Whites. The relationships between the type of stress (diabetes-specific and general stress) and DKA did not differ across racial/ethnic groups. Future research should evaluate possible mechanisms that contribute to the different relationships of stress with glycemic control among Hispanics compared with non-Hispanic Whites. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  7. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is

  8. Hybrid job shop scheduling

    NARCIS (Netherlands)

    Schutten, Johannes M.J.

    1995-01-01

    We consider the problem of scheduling jobs in a hybrid job shop. We use the term 'hybrid' to indicate that we consider a lot of extensions of the classic job shop, such as transportation times, multiple resources, and setup times. The Shifting Bottleneck procedure can be generalized to deal with

  9. General Formation of M(x)Co(3-x)S4 (M=Ni, Mn, Zn) Hollow Tubular Structures for Hybrid Supercapacitors.

    Science.gov (United States)

    Chen, Yu Ming; Li, Zhen; Lou, Xiong Wen David

    2015-09-01

    A simple and versatile method for general synthesis of uniform one-dimensional (1D) M(x)Co(3-x)S4 (M=Ni, Mn, Zn) hollow tubular structures (HTSs), using soft polymeric nanofibers as a template, is described. Fibrous core-shell polymer@M-Co acetate hydroxide precursors with a controllable molar ratio of M/Co are first prepared, followed by a sulfidation process to obtain core-shell polymer@M(x)Co(3-x)S4 composite nanofibers. The as-made M(x)Co(3-x)S4 HTSs have a high surface area and exhibit exceptional electrochemical performance as electrode materials for hybrid supercapacitors. For example, the MnCo2S4 HTS electrode can deliver specific capacitance of 1094 F g(-1) at 10 A g(-1), and the cycling stability is remarkable, with only about 6% loss over 20,000 cycles. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Nonlinear electronic excitations in crystalline solids using meta-generalized gradient approximation and hybrid functional in time-dependent density functional theory

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Shunsuke A. [Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571 (Japan); Taniguchi, Yasutaka [Center for Computational Science, University of Tsukuba, Tsukuba 305-8571 (Japan); Department of Medical and General Sciences, Nihon Institute of Medical Science, 1276 Shimogawara, Moroyama-Machi, Iruma-Gun, Saitama 350-0435 (Japan); Shinohara, Yasushi [Max Planck Institute of Microstructure Physics, 06120 Halle (Germany); Yabana, Kazuhiro [Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571 (Japan); Center for Computational Science, University of Tsukuba, Tsukuba 305-8571 (Japan)

    2015-12-14

    We develop methods to calculate electron dynamics in crystalline solids in real-time time-dependent density functional theory employing exchange-correlation potentials which reproduce band gap energies of dielectrics; a meta-generalized gradient approximation was proposed by Tran and Blaha [Phys. Rev. Lett. 102, 226401 (2009)] (TBm-BJ) and a hybrid functional was proposed by Heyd, Scuseria, and Ernzerhof [J. Chem. Phys. 118, 8207 (2003)] (HSE). In time evolution calculations employing the TB-mBJ potential, we have found it necessary to adopt the predictor-corrector step for a stable time evolution. We have developed a method to evaluate electronic excitation energy without referring to the energy functional which is unknown for the TB-mBJ potential. For the HSE functional, we have developed a method for the operation of the Fock-like term in Fourier space to facilitate efficient use of massive parallel computers equipped with graphic processing units. We compare electronic excitations in silicon and germanium induced by femtosecond laser pulses using the TB-mBJ, HSE, and a simple local density approximation (LDA). At low laser intensities, electronic excitations are found to be sensitive to the band gap energy: they are close to each other using TB-mBJ and HSE and are much smaller in LDA. At high laser intensities close to the damage threshold, electronic excitation energies do not differ much among the three cases.

  11. Cooccurrence of and remission from general anxiety, depression, and posttraumatic stress disorder symptoms after acute lung injury: a 2-year longitudinal study.

    Science.gov (United States)

    Bienvenu, O Joseph; Colantuoni, Elizabeth; Mendez-Tellez, Pedro A; Shanholtz, Carl; Dennison-Himmelfarb, Cheryl R; Pronovost, Peter J; Needham, Dale M

    2015-03-01

    To evaluate the cooccurrence, and predictors of remission, of general anxiety, depression, and posttraumatic stress disorder symptoms during 2-year follow-up in survivors of acute lung injury treated in an ICU. Prospective cohort study, with follow-up at 3, 6, 12, and 24 months post-acute lung injury. Thirteen medical and surgical ICUs in four hospitals. Survivors among 520 patients with acute lung injury. The outcomes of interest were measured using the Hospital Anxiety and Depression Scale anxiety and depression subscales (scores ≥ 8 indicating substantial symptoms) and the Impact of Event Scale-Revised (scores ≥ 1.6 indicating substantial posttraumatic stress disorder symptoms). Of the 520 enrolled patients, 274 died before 3-month follow-up; 186 of 196 consenting survivors (95%) completed at least one Hospital Anxiety and Depression Scale and Impact of Event Scale-Revised assessment during 2-year follow-up, and most completed multiple assessments. Across follow-up time points, the prevalence of suprathreshold general anxiety, depression, and posttraumatic stress disorder symptoms ranged from 38% to 44%, 26% to 33%, and 22% to 24%, respectively; more than half of the patients had suprathreshold symptoms in at least one domain during 2-year follow-up. The majority of survivors (59%) with any suprathreshold symptoms were above threshold for two or more types of symptoms (i.e., general anxiety, depression, and/or posttraumatic stress disorder). In fact, the most common pattern involved simultaneous general anxiety, depression, and posttraumatic stress disorder symptoms. Most patients with general anxiety, depression, or posttraumatic stress disorder symptoms during 2-year follow-up had suprathreshold symptoms at 24-month (last) follow-up. Higher Short-Form-36 physical functioning domain scores at the prior visit were associated with a greater likelihood of remission from general anxiety and posttraumatic stress disorder symptoms during follow-up. The majority

  12. Effort-reward and work-life imbalance, general stress and burnout among employees of a large public hospital in Switzerland

    OpenAIRE

    Hämmig, Oliver; Brauchli, Rebecca; Bauer, Georg F

    2012-01-01

    INTRODUCTION: Effort-reward imbalance (ERI) and work-life imbalance (WLI) are recognised risk factors for work stress and burnout but have not been investigated conjointly so far and compared with each other in this regard. The present cross-sectional study provides initial evidence by studying associations of ERI and WLI with general stress and burnout simultaneously. METHODS: The study was based on survey data collected in 2007 among the personnel of a large public hospital in the canton...

  13. WrpA Is an Atypical Flavodoxin Family Protein under Regulatory Control of the Brucella abortus General Stress Response System

    Energy Technology Data Exchange (ETDEWEB)

    Herrou, Julien; Czyż, Daniel M.; Willett, Jonathan W.; Kim, Hye-Sook; Chhor, Gekleng; Babnigg, Gyorgy; Kim, Youngchang; Crosson, Sean; Stock, A. M.

    2016-02-08

    ABSTRACT

    The general stress response (GSR) system of the intracellular pathogenBrucella abortuscontrols the transcription of approximately 100 genes in response to a range of stress cues. The core genetic regulatory components of the GSR are required forB. abortussurvival under nonoptimal growth conditionsin vitroand for maintenance of chronic infection in anin vivomouse model. The functions of the majority of the genes in the GSR transcriptional regulon remain undefined.bab1_1070is among the most highly regulated genes in this regulon: its transcription is activated 20- to 30-fold by the GSR system under oxidative conditionsin vitro. We have solved crystal structures of Bab1_1070 and demonstrate that it forms a homotetrameric complex that resembles those of WrbA-type NADH:quinone oxidoreductases, which are members of the flavodoxin protein family. However,B. abortusWrbA-relatedprotein (WrpA) does not bind flavin cofactors with a high affinity and does not function as an NADH:quinone oxidoreductasein vitro. Soaking crystals with flavin mononucleotide (FMN) revealed a likely low-affinity binding site adjacent to the canonical WrbA flavin binding site. Deletion ofwrpAwrpA) does not compromise cell survival under acute oxidative stressin vitroor attenuate infection in cell-based or mouse models. However, a ΔwrpAstrain does elicit increased splenomegaly in a mouse model, suggesting that WrpA modulatesB. abortusinteraction with its mammalian host. Despite

  14. Occupational stress and mental health among nurses in a medical intensive care unit of a general hospital in Bandar Abbas in 2013.

    Science.gov (United States)

    Tajvar, Abdolhamid; Saraji, Gebraeil Nasl; Ghanbarnejad, Amin; Omidi, Leila; Hosseini, Seyed Sodabeh Seyed; Abadi, Ali Salehi Sahl

    2015-07-01

    Many nurses have reported experiencing high levels of occupational stress in their work environment. Stress, as an outcome of stressful workplaces and tasks, affects nursing behavior in hospital wards. The objectives of this research were to determine the prevalence of occupational stress and mental health problems in nurses in the intensive care unit (ICU) at Shahid Mohammadi Hospital in Bandar Abbas in 2013 and to determine the relationship between occupational stress and mental health. This cross-sectional study was conducted in 2013 on all of the nurses working in ICU at Shahid Mohammadi Hospital located in Bandar Abbas, Iran. Seventy-two nurses were selected as the population for this study, and all of them were female. Two questionnaires were used in this study, i.e., General Health Questionnaire-28 (GHQ-28) for assessing mental health and an occupational stress test for assessing job stress. Furthermore, the relationship between occupational stress and mental health was examined. One-way analysis of variance (ANOVA), independent samples t-test, and Pearson's product-moment correlation test were used to analyze the data. High and moderate levels of occupational stress were experienced by 83.9% and 10.7% of ICU nurses, respectively. The prevalence of mental disorders, somatic symptoms, anxiety, social dysfunction, and depression were 58.9, 60.7, 62.5, 71.4, and 10.7%, respectively. The findings of the independent samples t-test showed that somatic symptoms had significant relationships with age and working experience (p = 0.01). According to the independent samples t-test, there were no significant differences between somatic symptoms and working different shifts (p > 0.05). There was a high prevalence of occupational stress among ICU nurses. There was a significant relationship between occupational stress and mental health. Future interventions are needed to codify a comprehensive health program in this field to reduce occupational stress and enhance nurses

  15. Comparison between general anesthesia and spinal anesthesia in attenuation of stress response in laparoscopic cholecystectomy: A randomized prospective trial

    Directory of Open Access Journals (Sweden)

    Writuparna Das

    2015-01-01

    Full Text Available Background: Laparoscopy though minimally invasive produces significant hemodynamic surge and neuroendocrine stress response. Though general anesthesia (GA is the conventional technique, now-a-days, regional anesthesia has been accepted for laparoscopic diagnostic procedures, and its use is also being extended to laparoscopic surgeries. Objective: The aim was to compare the hemodynamic surge and neuroendocrine stress response during laparoscopic cholecystectomy (LC under GA and spinal anesthesia (SA in American Society of Anesthesiologists (ASA PS 1 patients. Materials and Methods: Thirty ASA physical status I patients, aged 18-65 years were randomly allocated into two equal groups of 15 each. Group A received GA with controlled ventilation. Patients were preoxygenated for 5 min with 100/5 oxygen, premedicated with midazolam 0.03 mg/kg intravenous (i.v, fentanyl 2 mcg/kg i.v; induction was done with thiopentone 3-5 mg/kg i.v; intubation was achieved after muscle relaxation with 0.5 mg/kg atracurium besylate i.v. Anesthesia was maintained with 1-2% sevoflurane and N2O:O2 (60:40 and intermittent i.v injection of atracurium besylate. Group B SA with 0.5% hyperbaric bupivacaine and 25 μg fentanyl along with local anesthetic instillation in the subdiaphragmatic space. Mean arterial pressure, heart rate (HR, oxygen saturation, end tidal carbon-dioxide were recorded. Venous blood was collected for cortisol assay before induction and 30 min after pneumoperitoneum. All data were collected in Microsoft excel sheet and statistically analyzed using SPSS software version 16 (SPSS Inc., Chicago, IL, USA. All numerical data were analyzed using Student′s t-test and paired t-test. Any value <0.05 was taken as significant. Results: Mean arterial pressure and mean HR and postpneumoperitoneum cortisol level were lower in group B than group A though the difference was not statistically significant in hemodynamic parameters but significant in case of cortisol

  16. Hybrid Qualifications

    DEFF Research Database (Denmark)

    Against the background of increasing qualification needs there is a growing awareness of the challenge to widen participation in processes of skill formation and competence development. At the same time, the issue of permeability between vocational education and training (VET) and general education...... has turned out as a major focus of European education and training policies and certainly is a crucial principle underlying the European Qualifications Framework (EQF). In this context, «hybrid qualifications» (HQ) may be seen as an interesting approach to tackle these challenges as they serve «two...

  17. Understanding the relationship between stress, distress and healthy lifestyle behaviour: a qualitative study of patients and general practitioners.

    Science.gov (United States)

    McKenzie, Suzanne H; Harris, Mark F

    2013-11-01

    The process of initiating and maintaining healthy lifestyle behaviours is complex, includes a number of distinct phases and is not static. Theoretical models of behaviour change consider psychological constructs such as intention and self efficacy but do not clearly consider the role of stress or psychological distress. General practice based interventions addressing lifestyle behaviours have been demonstrated to be feasible and effective however it is not clear whether general practitioners (GPs) take psychological health into consideration when discussing lifestyle behaviours. This qualitative study explores GPs' and patients' perspectives about the relationship between external stressors, psychological distress and maintaining healthy lifestyle behaviours. Semi-structured telephone interviews were conducted with 16 patients and 5 GPs. Transcripts from the interviews were thematically analysed and a conceptual model developed to explain the relationship between external stressors, psychological distress and healthly lifestyle behaviours. Participants were motivated to maintain a healthy lifestyle however they described a range of external factors that impacted on behaviour in both positive and negative ways, either directly or via their impact on psychological distress. The impact of external factors was moderated by coping strategies, beliefs, habits and social support. In some cases the process of changing or maintaining healthy behaviour also caused distress. The concept of a threshold level of distress was evident in the data with patients and GPs describing a certain level of distress required before it negatively influenced behaviour. Maintaining healthy lifestyle behaviours is complex and constantly under challenge from external stressors. Practitioners can assist patients with maintaining healthy behaviour by providing targeted support to moderate the impact of external stressors.

  18. Latent profile analyses of posttraumatic stress disorder, depression and generalized anxiety disorder symptoms in trauma-exposed soldiers.

    Science.gov (United States)

    Contractor, Ateka A; Elhai, Jon D; Fine, Thomas H; Tamburrino, Marijo B; Cohen, Gregory; Shirley, Edwin; Chan, Philip K; Liberzon, Israel; Galea, Sandro; Calabrese, Joseph R

    2015-09-01

    Posttraumatic stress disorder (PTSD) is comorbid with major depressive disorder (MDD; Kessler et al., 1995) and generalized anxiety disorder (GAD; Brown et al., 2001). We aimed to (1) assess discrete patterns of post-trauma PTSD-depression-GAD symptoms using latent profile analyses (LPAs), and (2) assess covariates (gender, income, education, age) in defining the best fitting class solution. The PTSD Checklist (assessing PTSD symptoms), GAD-7 scale (assessing GAD symptoms), and Patient Health Questionnaire-9 (assessing depression) were administered to 1266 trauma-exposed Ohio National Guard soldiers. Results indicated three discrete subgroups based on symptom patterns with mild (class 1), moderate (class 2) and severe (class 3) levels of symptomatology. Classes differed in symptom severity rather than symptom type. Income and education significantly predicted class 1 versus class 3 membership, and class 2 versus class 3. In conclusion, there is heterogeneity regarding severity of PTSD-depression-GAD symptomatology among trauma-exposed soldiers, with income and education predictive of class membership. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Effort-reward and work-life imbalance, general stress and burnout among employees of a large public hospital in Switzerland.

    Science.gov (United States)

    Hämmig, Oliver; Brauchli, Rebecca; Bauer, Georg F

    2012-05-31

    Effort-reward imbalance (ERI) and work-life imbalance (WLI) are recognised risk factors for work stress and burnout but have not been investigated conjointly so far and compared with each other in this regard. The present cross-sectional study provides initial evidence by studying associations of ERI and WLI with general stress and burnout simultaneously. The study was based on survey data collected in 2007 among the personnel of a large public hospital in the canton of Zurich covering a random sample of 502 employees of all professions and positions. Prevalence rates, correlation coefficients, standardised regression coefficients and odds ratios were calculated as measures of association. Concerning the main research question and relating to the entire study sample, WLI was found to be more strongly associated with general stress and burnout than ERI. As stratified analyses with regard to burnout have shown, this applied especially to nursing, technical care and emergency staffs who account for more than three fifths of the study population. But for other professional categories like physicians, therapists and medical-technical personnel the opposite of a stronger association of ERI with burnout was found. Results also suggested that general stress plays a (rather minor) mediating role in the relationships between ERI and burnout and particularly between WLI and burnout. For the prevention of chronic stress and burnout one should consider both high efforts put into work as well as all job demands that are competing and interfering with family responsibilities or other private activities should be considered.

  20. What are the sources of stress and distress for general practitioners working in England? A qualitative study.

    Science.gov (United States)

    Riley, Ruth; Spiers, Johanna; Buszewicz, Marta; Taylor, Anna Kathryn; Thornton, Gail; Chew-Graham, Carolyn Anne

    2018-01-11

    This paper reports the sources of stress and distress experienced by general practitioners (GP) as part of a wider study exploring the barriers and facilitators to help-seeking for mental illness and burnout among this medical population. Qualitative study using in-depth interviews with 47 GP participants. The interviews were audio-recorded, transcribed, anonymised and imported into NVivo V.11 to facilitate data management. Data were analysed using a thematic analysis employing the constant comparative method. England. A purposive sample of GP participants who self-identified as: (1) currently living with mental distress, (2) returning to work following treatment, (3) off sick or retired early as a result of mental distress or (4) without experience of mental distress. Interviews were conducted face-to-face or over the telephone. The key sources of stress/distress related to: (1) emotion work-the work invested and required in managing and responding to the psychosocial component of GPs' work, and dealing with abusive or confrontational patients; (2) practice culture-practice dynamics and collegial conflict, bullying, isolation and lack of support; (3) work role and demands-fear of making mistakes, complaints and inquests, revalidation, appraisal, inspections and financial worries. In addition to addressing escalating workloads through the provision of increased resources, addressing unhealthy practice cultures is paramount. Collegial support, a willingness to talk about vulnerability and illness, and having open channels of communication enable GPs to feel less isolated and better able to cope with the emotional and clinical demands of their work. Doctors, including GPs, are not invulnerable to the clinical and emotional demands of their work nor the effects of divisive work cultures-culture change and access to informal and formal support is therefore crucial in enabling GPs to do their job effectively and to stay well. © Article author(s) (or their employer

  1. Association between the Five Factor personality traits and perceived stress: is the effect mediated by general self-efficacy?

    DEFF Research Database (Denmark)

    Ebstrup, Jeanette Frost; Eplov, Lene Falgaard; Pisinger, Charlotta

    2011-01-01

    Ill-health resulting from chronic stress is influenced by personality traits leading to different ways of appraising and coping with life's daily hassles. Using a large population sample the study aimed to investigate possible associations between perceived stress and the personality dimensions......-significant - whilst neuroticism had a positive association. The associations with agreeableness and openness became positive and significant, respectively, when GSE was included. All five personality-stress models were mediated by GSE, with extroversion and conscientiousness having the strongest mediating effect....... The strongest stress-association was found for neuroticism. GSE was shown to change the impact and interpretation of the personality dimensions on perceived stress. These results indicate that GSE is an important factor to consider in the link between personality and perceived stress....

  2. Effectiveness of a minimal intervention for stress-related mental disorders with sick leave (MISS): study protocol of a cluster randomised controlled trial in general practice [ISRCTN43779641

    NARCIS (Netherlands)

    Bakker, I.M.; Terluin, B.; van Marwijk, H.W.J.; Cundy, C.M.; Smit, J.H.; van Mechelen, W.; Stalman, W.A.B.

    2006-01-01

    Background: The main aims of this paper are to describe the setting and design of a Minimal Intervention in general practice for Stress-related mental disorders in patients on Sick leave (MISS), as well as to ascertain the study complies with the requirements for a cluster randomised controlled

  3. Big Five Personality Traits and the General Factor of Personality as Moderators of Stress and Coping Reactions Following an Emergency Alarm on a Swiss University Campus

    NARCIS (Netherlands)

    M.P. Hengartner (Michael P.); D. van der Linden (Dimitri); L. Bohleber (Laura); A. von Wyl (Agnes)

    2017-01-01

    textabstractWe conducted an online survey including 306 participants aged 18-64years to assess the general factor of personality (GFP) and Big Five personality traits in relation to individual stress and coping reactions following a shooting emergency alarm at a Swiss university campus. Although the

  4. Spinal pain and co-occurrence with stress and general well-being among young adolescents: a study within the Danish National Birth Cohort.

    Science.gov (United States)

    Stallknecht, Sandra Elkjær; Strandberg-Larsen, Katrine; Hestbæk, Lise; Andersen, Anne-Marie Nybo

    2017-06-01

    This study aims to describe the patterns in low back, mid back, and neck pain complaints in young adolescents from the Danish National Birth Cohort (DNBC) and to investigate the co-occurrence of spinal pain and stress and general well-being, respectively. Cross-sectional data from the 11-year follow-up of DNBC were used. As part of a web-based survey, a total of 45,371 young adolescents between 10 and 14 years old completed the Young Spine Questionnaire, the Stress in Children Questionnaire, and a one-item question on general well-being. Associations between spinal pain and, respectively, stress and general well-being were estimated by means of multiple logistic regression models. Almost one fifth of boys and one quarter of girls reported spinal pain. Compared with adolescents who reported no stress, adolescents reporting medium and high values of stress had odds ratios (OR) of 2.19 (95% CI 2.08-2.30) and 4.73 (95% CI 4.28-5.23), respectively, of reporting spinal pain (adjusted for age, gender, and maternal education). Adolescents who reported poor general well-being had an OR of 2.50 (95% CI 2.31-2.72) for reporting spinal pain compared to adolescents with good general well-being. Spinal pain is a common complaint among young adolescents and co-occurs with stress and poor general well-being. The mutual dependency between the factors remained to be explained. What is Known: • The prevalence of spinal pain increases rapidly during childhood and adolescence, but different measurement instruments result in great variation in the estimates of spinal pain in children and adolescents. • Some studies have shown that different psychosocial measures are associated with spinal pain in children and adolescents. What is New: • Spinal pain, as measured by the newly developed and validated Young Spine Questionnaire, is a common complaint in young adolescents aged 10-14 years. • Spinal pain in young adolescents co-occurs with stress and poor general well-being.

  5. The generalized fracture criteria based on the multi-parameter representation of the crack tip stress field

    Science.gov (United States)

    Stepanova, L. V.

    2017-12-01

    The paper is devoted to the multi-parameter asymptotic description of the stress field near the crack tip of a finite crack in an infinite isotropic elastic plane medium subject to 1) tensile stress; 2) in-plane shear; 3) mixed mode loading for a wide range of mode-mixity situations (Mode I and Mode II). The multi-parameter series expansion of stress tensor components containing higher-order terms is obtained. All the coefficients of the multiparameter series expansion of the stress field are given. The main focus is on the discussion of the influence of considering the higher-order terms of the Williams expansion. The analysis of the higher-order terms in the stress field is performed. It is shown that the larger the distance from the crack tip, the more terms it is necessary to keep in the asymptotic series expansion. Therefore, it can be concluded that several more higher-order terms of the Williams expansion should be used for the stress field description when the distance from the crack tip is not small enough. The crack propagation direction angle is calculated. Two fracture criteria, the maximum tangential stress criterion and the strain energy density criterion, are used. The multi-parameter form of the two commonly used fracture criteria is introduced and tested. Thirty and more terms of the Williams series expansion for the near-crack-tip stress field enable the angle to be calculated more precisely.

  6. Hybrid functional pseudopotentials

    Science.gov (United States)

    Yang, Jing; Tan, Liang Z.; Rappe, Andrew M.

    2018-02-01

    The consistency between the exchange-correlation functional used in pseudopotential construction and in the actual density functional theory calculation is essential for the accurate prediction of fundamental properties of materials. However, routine hybrid density functional calculations at present still rely on generalized gradient approximation pseudopotentials due to the lack of hybrid functional pseudopotentials. Here, we present a scheme for generating hybrid functional pseudopotentials, and we analyze the importance of pseudopotential density functional consistency for hybrid functionals. For the PBE0 hybrid functional, we benchmark our pseudopotentials for structural parameters and fundamental electronic gaps of the Gaussian-2 (G2) molecular dataset and some simple solids. Our results show that using our PBE0 pseudopotentials in PBE0 calculations improves agreement with respect to all-electron calculations.

  7. Predictors of parent post-traumatic stress symptoms after child hospitalization on general pediatric wards: a prospective cohort study.

    Science.gov (United States)

    Franck, Linda S; Wray, Jo; Gay, Caryl; Dearmun, Annette K; Lee, Kirsty; Cooper, Bruce A

    2015-01-01

    The aim of this study was to identify predictors of parental post-traumatic stress symptoms following child hospitalization. In this prospective cohort study, a sample of 107 parents completed questionnaires during their child's hospitalization on pediatric (non-intensive care) wards and again three months after discharge. Eligible parents had a child expected to be hospitalized for three or more nights. Standardized questionnaires were used to assess parent distress during the child's hospitalization, parent coping strategies and resources, and symptoms of post-traumatic stress after the hospitalization. Correlations and multiple regressions were used to determine whether parent distress during hospitalization and coping strategies and resources predicted post-traumatic stress symptoms three months after the child's discharge, while controlling for relevant covariates. Three months after the child's hospital discharge, 32.7% of parents (n=35) reported some degree of post-traumatic stress symptoms, and 21.5% (n=23) had elevated (≥34) scores consistent with a probable diagnosis of post-traumatic stress disorder. In the multivariable model, parent anxiety and uncertainty during hospitalization and use of negative coping strategies, such as denial, venting and self-blame, were associated with higher post-traumatic stress symptoms scores at three months post-discharge, even after controlling for the child's health status. Parental anxiety and depression during hospitalization moderated the relationship between negative coping strategies and post-traumatic stress symptoms. More than one quarter of parents of children hospitalized on pediatric (non-intensive care) wards experienced significant post-traumatic stress symptoms after their child's discharge. Parents' hospital-related anxiety, uncertainty and use of negative coping strategies are potentially modifiable factors that most strongly influenced post-traumatic stress symptoms. Further research is urgently needed

  8. Pricing of Traffic Light Options and other Hybrid Products

    DEFF Research Database (Denmark)

    Kokholm, Thomas

    2009-01-01

    companies stay solvent in the traffic light stress test system introduced by the Danish Financial Supervisory Authorities in 2001. Similar systems are now being implemented in several other European countries. A pricing approach for general payoffs is presented and illustrated with simulation via...... the pricing of a hybrid derivative known as the EUR Sage Note. The approach can be used to price many existing structured products....

  9. A Comuputerized DRBEM model for generalized magneto-thermo-visco-elastic stress waves in functionally graded anisotropic thin film/substrate structures

    Directory of Open Access Journals (Sweden)

    Mohamed Abdelsabour Fahmy

    Full Text Available A numerical computer model, based on the dual reciprocity boundary element method (DRBEM for studying the generalized magneto-thermo-visco-elastic stress waves in a rotating functionally graded anisotropic thin film/substrate structure under pulsed laser irradiation is established. An implicit-implicit staggered algorithm was proposed and implemented for use with the DRBEM to get the solution for the temperature, displacement components and thermal stress components through the structure thickness. A comparison of the results for different theories is presented in the presence and absence of rotation. Some numerical results that demonstrate the validity of the proposed method are also presented.

  10. Effectiveness of stress-management training in the first trimester of pregnancy on improvement of stress reduction in General Moheb Yas Women Hospital

    Directory of Open Access Journals (Sweden)

    Marzieh Shirazi

    2016-10-01

    Method: This randomized clinical trial study was performed on 75 pregnant women in their first trimester of pregnancy. These women were referred to the hospital for regular prenatal care. They were assessed by standard anxiety questioner, using Hamilton anxiety scale. The validity and reliability of questioner were approved by experts in this field. Based on Hamilton Scale, the pregnant women were divided to three groups. Pregnant women with low, moderate and sever level anxiety, had18-25, 25-35, and more than 35 scales respectively. According to the level of their anxiety, women in moderate and sever anxiety, as clinical groups, were arranged for stress management workshop based on mindfulness technique in 60 minutes in 5 session per week. For this experimental group were made available compact disk (CD training for practicing lessons during the week. Mindfulness technique was including: Body scan, setting meditation and passing thought technique. Low anxiety level group, as control group, had regular pregnancy care. The groups didn’t need to medical treatment according to the psychiatrist interview. In the ending of therapy, clinical and control groups were assessed by anxiety scale again. Data were analyzed using the statistical software SPSS version 18, T- test analysis was performed. The IRCT code was IRCT2013081814174N2. Results: In this study, it was demonstrated, the level of anxiety and stress was decreased significantly between women in clinical groups, 27.5 to 14.1 for moderated level stress (p=0.001 and 40.1 to16.6 for high level of stress (p=0.001 respectively.. Conclusion: Based on our findings, psychological intervention has beneficial effect on stress reduction during pregnancy. It have direct influence on maternal health status.

  11. Generalized product

    OpenAIRE

    Greco, Salvatore; Mesiar, Radko; Rindone, Fabio

    2014-01-01

    Aggregation functions on [0,1] with annihilator 0 can be seen as a generalized product on [0,1]. We study the generalized product on the bipolar scale [–1,1], stressing the axiomatic point of view. Based on newly introduced bipolar properties, such as the bipolar increasingness, bipolar unit element, bipolar idempotent element, several kinds of generalized bipolar product are introduced and studied. A special stress is put on bipolar semicopulas, bipolar quasi-copulas and bipolar copulas.

  12. Stability Parameters for Grain Yield and its Component Traits in Maize Hybrids of Different FAO Maturity Groups

    Directory of Open Access Journals (Sweden)

    Dragan Djurovic

    2014-12-01

    Full Text Available An objective evaluation of maize hybrids in intensive cropping systems requires identification not only of yield components and other agronomically important traits but also of stability parameters. Grain yield and its components were assessed in 11 maize hybrids with different lengths of growing season (FAO 300-700 maturity groups using analysis of variance and regression analysis at three different locations in Western Serbia. The test hybrids and locations showed significant differences in grain yield, grain moisture content at maturity, 1,000-kernel weight and ear length. A significant interaction was observed between all traits and the environment. The hybrids with higher mean values of the traits, regardless of maturity group, generally exhibited sensitivity i.e. adaptation to more favourable environmental conditions as compared to those having lower mean values. Regression coefficient (bi values for grain yield mostly suggested no significant differences relative to the mean. The medium-season hybrid gave high yields and less favourable values of stability parameters at most locations and in most years, as compared to mediumlate hybrids. As compared to medium-early hybrids, medium-late hybrids (FAO 600 and 700 mostly exhibited unfavourable values of stability parameters i.e. a specific response and better adaptation to favourable environmental conditions, and gave higher average yields. Apart from producing lower average yields, FAO 300 and 400 hybrids showed higher yield stability as compared to the other hybrids tested. Medium-late hybrids had higher yields and showed a better response to favourable environmental conditions compared to early-maturing hybrids. Therefore, they can be recommended for intensive cultural practices and low-stress environments. Due to their more favourable stability parameter values, medium-early hybrids can be recommended for low-intensity cultural practices and stressful environments.

  13. General practitioners knowledge and management of whiplash associated disorders and post-traumatic stress disorder: implications for patient care.

    Science.gov (United States)

    Brijnath, Bianca; Bunzli, Samantha; Xia, Ting; Singh, Nabita; Schattner, Peter; Collie, Alex; Sterling, Michele; Mazza, Danielle

    2016-07-20

    In Australia, general practitioners (GPs) see around two-thirds of people injured in road traffic crashes. Road traffic crash injuries are commonly associated with diverse physical and psychological symptoms that may be difficult to diagnose and manage. Clinical guidelines have been developed to assist in delivering quality, consistent care, however the extent to which GPs knowledge and practice in diagnosing and managing road traffic crash injuries concords with the guidelines is unknown. This study aimed to explore Australian GPs knowledge, attitudes and practices regarding the diagnosis and management of road traffic crash injuries, specifically whiplash associated disorders (WAD) and post-traumatic stress disorder (PTSD). A cross-sectional survey of 423 GPs across Australia conducted between July and December 2014. We developed a questionnaire to assess their knowledge of WAD and PTSD, confidence in diagnosing and managing WAD and PTSD, frequency of referral to health providers, barriers to referral, and attitudes towards further education and training. Factor analysis, Spearman's correlation, and multiple ordered logistic regressions were performed. Overall, GPs have good level knowledge of WAD and PTSD; only 9.6 % (95 % CI: 7.1 %, 12.8 %) and 23.9 % (95 % CI: 20.8 %, 28.2 %) of them were deemed to have lower level knowledge of WAD and PTSD respectively. Key knowledge gaps included imaging indicators for WAD and indicators for psychological referral for PTSD. GPs who were male, with more years of experience, working in the urban area and with higher knowledge level of WAD were more confident in diagnosing and managing WAD. Only GPs PTSD knowledge level predicted confidence in diagnosing and managing PTSD. GPs most commonly referred to physiotherapists and least commonly to vocational rehabilitation providers. Barriers to referral included out-of-pocket costs incurred by patients and long waiting times. Most GPs felt positive towards further education

  14. Hybrid quantum-classical master equations

    International Nuclear Information System (INIS)

    Diósi, Lajos

    2014-01-01

    We discuss hybrid master equations of composite systems, which are hybrids of classical and quantum subsystems. A fairly general form of hybrid master equations is suggested. Its consistency is derived from the consistency of Lindblad quantum master equations. We emphasize that quantum measurement is a natural example of exact hybrid systems. We derive a heuristic hybrid master equation of time-continuous position measurement (monitoring). (paper)

  15. The Effectiveness of Group Training of CBT-Based Stress Management on Anxiety, Psychological Hardiness and General Self-Efficacy Among University Students.

    Science.gov (United States)

    Molla Jafar, Hamdam; Salabifard, Seddigheh; Mousavi, Seyedeh Maryam; Sobhani, Zahra

    2015-09-28

    Admission to university is a very sensitive period of life for efficient, active, and young workforces in any country, and it is mostly associated with many changes in social and human relationships. These changes lead to anxiety in students. Moreover, humans need certain functions in order to adaptively deal with different life situations and challenges. By training stress management, these functions can help human acquire the required abilities. The present study was aimed at investigating the effectiveness of stress management training in anxiety, psychological hardiness, and general self-efficacy among university students. The study was a quasi-experimental intervention (pretest-posttest-follow-up) including a control group, it was a fundamental applied study. The statistical population consisted of all students of Islamic Azad University, Karaj, Iran. Convenient sampling was employed to select 30 students who were divided into an experimental group (n=15) and a control group (n=15). Before stress management training, both groups filled out Beck Anxiety Inventory, Long and Goulet scale of psychological hardiness, and General Self-efficacy Scale (GSE-10). Afterwards, the experimental group was provided with stress management training. And after the experiment, the abovementioned questionnaires and scales were responded by the two groups. Finally the collected data were analyzed and compared using one-way MANOVA. The results of MANOVA indicated that there was a significant difference between the two groups in terms of anxiety, hardiness, and general self-efficacy (pstress management among university students cause anxiety to drop; moreover, it enhances their psychological hardiness and self-efficacy. In regard with the role and importance of stress management, training this skill should be included in educational plans of university.

  16. A General Discussion of Problems Related to the Determination of Concrete Armour Unit Stresses Including Specific Results related to Static and Dynamic Stresses in Dolosse

    DEFF Research Database (Denmark)

    Burcharth, H. F.; Liu, Zhou

    1989-01-01

    Recent breakwater failures revealed the shortcomings of the traditional design procedures for concrete armour units. This paper deals with one of them, which can be expressed as the "lack of balance between the hydraulic stability of the armour layer and the mechanical strength or integrity...... of the units". This problem is related mainly to the slender types of armour units. The paper discusses the various types of loads, and the practical determination of the wave and gravity induced loads and stresses, especially the model test technique and its restrictions. Examples related to Dolosse...

  17. General quantitative analysis of stress partitioning and boundary conditions in undrained biphasic porous media via a purely macroscopic and purely variational approach

    Science.gov (United States)

    Serpieri, Roberto; Travascio, Francesco

    2016-03-01

    In poroelasticity, the effective stress law relates the external stress applied to the medium to the macroscopic strain of the solid phase and the interstitial pressure of the fluid saturating the mixture. Such relationship has been formerly introduced by Terzaghi in form of a principle. To date, no poroelastic theory is capable of recovering a stress partitioning law in agreement with Terzaghi's postulated one in the absence of ad hoc constitutive assumptions on the medium. We recently proposed a variational macroscopic continuum description of two-phase poroelasticity to derive a general biphasic formulation at finite deformations, termed variational macroscopic theory of porous media (VMTPM). Such approach proceeds from the inclusion of the intrinsic volumetric strain among the kinematic descriptors aside to macroscopic displacements, and as a variational theory, uses the Hamilton least-action principle as the unique primitive concept of mechanics invoked to derive momentum balance equations. In a previous related work it was shown that, for the subclass of undrained problems, VMTPM predicts that stress is partitioned in the two phases in strict compliance with Terzaghi's law, irrespective of the microstructural and constitutive features of a given medium. In the present contribution, we further develop the linearized framework of VMTPM to arrive at a general operative formula that allows the quantitative determination of stress partitioning in a jacketed test over a generic isotropic biphasic specimen. This formula is quantitative and general, in that it relates the partial phase stresses to the externally applied stress as function of partitioning coefficients that are all derived by strictly following a purely variational and purely macroscopic approach, and in the absence of any specific hypothesis on the microstructural or constitutive features of a given medium. To achieve this result, the stiffness coefficients of the theory are derived by using

  18. Evaluation of inter-specific hybrid of P. atlantica and P. vera L. cv. ‘Badami Riz-e-Zarand’ as pistachio rootstock to salinity stress according to some growth indices and eco-physiological and biochemical parameters

    OpenAIRE

    Karimi, Hamid; MALEKI-KUHBANANI; Roosta, H.

    2014-01-01

    In order to evaluate the inter-specific hybrid of P. atlantica Desf. and P. vera L. cv. ‘Badami- Riz-e- Zarand’ to salinity stress, a factorial experiment was conducted based on completely randomized design with 0, 60 and 120 mM of salinity levels of sodium chloride, calcium chloride and magnesium chloride (3:2:1) with four replications on ‘Qazvini’, ‘Badami-Riz-e-Zarand’ and inter-specific of P. atlantica Ч P. vera cv. ‘Badami-Rize-Zarand’ rootstocks of pistachio. The results showed that sa...

  19. [Stress syndrome in patients receiving outpatient treatment at the General Hospital, in Bangui, in a context of armed conflict].

    Science.gov (United States)

    Mpembi, Magloire Nkosi; Lukeba, Thierry; Mayemba, Damien; Massamba, Victoria Kubuta; Ma Nzuzi, Thierry Matonda; Gokara, Symphorien; Vermeiren, Etienne; Mananga Lelo, Gilbert; Ma Miezi, Samuel Mampunza

    2018-01-01

    in Africa's zones of conflict, recent studies report a high frequency of post-traumatic stress disorder (PTSD) particularly in community settings. This study aimed to contribute to a better management of patients experiencing violence subsequent to the Central African Republic socio-political conflict. We conducted a cross-sectional study of the medical records of patients receiving outpatient treatment in the Doctors Without Borders/Médecins Sans Frontières (France) Trauma Center, Bangui. 33.33% (n=35) of patients had PTSD, while 17.14% (n=18) of patients had acute stress syndrome. Stress syndrome (SS) was associated with female sex, rape, anxiety and depression. Rape multiplied the risk of SS occurrence by 8. The average age was 30 years (P25:22 years; P75:40 years). The majority of patients had mood disorder (63.81%; n=67). Insomnia was present in 62.83% (n=66) of patients. Hospital Anxiety and Depression Scale (HADS) was present in 44.76 % of patients. Depression was found in 40.95% (n=43) of patients. The obtained results show how the society, apart from militia members, is affected by conflict-related violence in the country. These results can enrich the reflections on health organisation and on the management of patients in Central African, by considering the impact of conflict-related acute stress syndome in the short, medium and long term.

  20. Analysis of Students’ Missed Organic Chemistry Quiz Questions that Stress the Importance of Prior General Chemistry Knowledge

    OpenAIRE

    Julie Ealy

    2018-01-01

    A concern about students’ conceptual difficulties in organic chemistry prompted this study. It was found that prior knowledge from general chemistry was critical in organic chemistry, but what were some of the concepts that comprised that prior knowledge? Therefore an analysis of four years of organic chemistry quiz data was undertaken. Multiple general chemistry concepts were revealed that are essential prior knowledge in organic chemistry. The general chemistry concepts that were foun...

  1. Effect of intercostal nerve block combined with general anesthesia on the stress response in patients undergoing minimally invasive mitral valve surgery.

    Science.gov (United States)

    Zhan, Yanping; Chen, Guo; Huang, Jian; Hou, Benchao; Liu, Weicheng; Chen, Shibiao

    2017-10-01

    The aim of the present study was to investigate the effect of intercostal nerve block combined with general anesthesia on the stress response and postoperative recovery in patients undergoing minimally invasive mitral valve surgery (MIMVS). A total of 30 patients scheduled for MIMVS were randomly divided into two groups (n=15 each): Group A, which received intercostal nerve block combined with general anesthesia and group B, which received general anesthesia alone. Intercostal nerve block in group A was performed with 0.5% ropivacaine from T3 to T7 prior to anesthesia induction. In each group, general anesthesia was induced using midazolam, sufentanil, propofol and vecuronium. Central venous blood samples were collected to determine the concentrations of cortisol, glucose, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) at the following time points: During central venous catheterization (T 1 ), 5 min prior to cardiopulmonary bypass (T 2 ), perioperative (T 3 ) and 24 h following surgery (T 4 ). Clinical data, including parameters of opioid (sufentanil) consumption, time of mechanical ventilation, duration of intensive care unit (ICU) stay, visual analog scale scores and any complications arising from intercostal nerve block, were recorded. Levels of cortisol, glucose, IL-6 and TNF-α in group A were significantly lower than those in group B at T 2 (all Pblock combined with general anesthesia may inhibit the stress response to MIMVS. Additionally, intercostal nerve block combined with general anesthesia may significantly reduce sufentanil consumption (Pblock combined with general anesthesia conforms to the concept of rapid rehabilitation surgery and may be suitable for clinical practice.

  2. Numbing of Positive, Negative, and General Emotions: Associations With Trauma Exposure, Posttraumatic Stress, and Depressive Symptoms Among Justice-Involved Youth.

    Science.gov (United States)

    Kerig, Patricia K; Bennett, Diana C; Chaplo, Shannon D; Modrowski, Crosby A; McGee, Andrew B

    2016-04-01

    Increasing attention has been drawn to the symptom of emotional numbing in the phenomenology of posttraumatic stress disorder (PTSD), particularly regarding its implications for maladaptive outcomes in adolescence such as delinquent behavior. One change in the definition of emotional numbing according to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013) was the limitation to the numbing of positive emotions. Previous research with youth, however, has implicated general numbing or numbing of negative emotions in PTSD, whereas numbing of positive emotions may overlap with other disorders, particularly depression. Consequently, the goal of this study was to investigate whether numbing of positive emotions was associated with PTSD symptoms above and beyond numbing of negative emotions, general emotional numbing, or depressive symptoms among at-risk adolescents. In a sample of 221 detained youth (mean age = 15.98 years, SD = 1.25; 50.7% ethnic minority), results of hierarchical multiple regressions indicated that only general emotional numbing and numbing of anger accounted for significant variance in PTSD symptoms (total R(2) = .37). In contrast, numbing of sadness and positive emotions were statistical correlates of depressive symptoms (total R(2) = .24). Further tests using Hayes' Process macro showed that general numbing, 95% CI [.02, .45], and numbing of anger, 95% CI [.01, .42], demonstrated indirect effects on the association between trauma exposure and PTSD symptoms. Copyright © 2016 International Society for Traumatic Stress Studies.

  3. Effect of general anesthesia combined with epidural anesthesia on the postoperative immune function, stress state and coagulation function in patients with laparoscopic cholecystectomy

    Directory of Open Access Journals (Sweden)

    Yun-Long Zhao

    2017-05-01

    Full Text Available Objective: To study the effect of general anesthesia combined with epidural anesthesia on the postoperative immune function, stress state and coagulation function in patients with laparoscopic cholecystectomy. Methods: 98 patients undergoing selective laparoscopic cholecystectomy in our hospital between May 2014 and August 2016 were selected and randomly divided into the combined anesthesia group who accepted the general anesthesia combined with epidural anesthesia and the general anesthesia group who accepted the total intravenous anesthesia (n=49, peripheral blood was collected after operation to detect the number of CD3+CD4+CD8-T cells, CD3+CD4-CD8+T cells, CD16+CD56+NK cells and CD3- CD19+B cells, serum was collected to detect the levels of stress-related endocrine hormones norepinephrine (NE, cortisol (Cor, insulin (Ins, C-peptide (C-P, free triiodothyronine (FT3, free thyroxine (FT4 as well as coagulation function indexes rostaglandin I2 (PGI2, thromboxane A2 (TXA2, 6-ketone-prostaglandin F1α (6-K-PGI1α and thromboxane B2 (TXB2. Results: The number of CD3+CD4+CD8-T cells, CD3+CD4-CD8+T cells, CD16+CD56+NK cells and CD3-CD19+B cells in peripheral blood of combined anesthesia group were significantly higher than those of intravenous anesthesia group (P<0.05; serum NE, Cor, Ins, C-P, FT3, FT4, TXA2 and TXB2 levels of combined anesthesia group were significantly lower than those of intravenous anesthesia group (P<0.05 while PGI2 and 6-K-PGI1α levels were significantly higher than those of intravenous anesthesia group (P<0.05. Conclusions: General anesthesia combined with epidural anesthesia can improve the postoperative immune function, stress state and hypercoagulable state in patients with laparoscopic cholecystectomy.

  4. From hybrid swarms to swarms of hybrids

    Science.gov (United States)

    Stohlgren, Thomas J.; Szalanski, Allen L; Gaskin, John F.; Young, Nicholas E.; West, Amanda; Jarnevich, Catherine S.; Tripodi, Amber

    2014-01-01

    Science has shown that the introgression or hybridization of modern humans (Homo sapiens) with Neanderthals up to 40,000 YBP may have led to the swarm of modern humans on earth. However, there is little doubt that modern trade and transportation in support of the humans has continued to introduce additional species, genotypes, and hybrids to every country on the globe. We assessed the utility of species distributions modeling of genotypes to assess the risk of current and future invaders. We evaluated 93 locations of the genus Tamarix for which genetic data were available. Maxent models of habitat suitability showed that the hybrid, T. ramosissima x T. chinensis, was slightly greater than the parent taxa (AUCs > 0.83). General linear models of Africanized honey bees, a hybrid cross of Tanzanian Apis mellifera scutellata and a variety of European honey bee including A. m. ligustica, showed that the Africanized bees (AUC = 0.81) may be displacing European honey bees (AUC > 0.76) over large areas of the southwestern U.S. More important, Maxent modeling of sub-populations (A1 and A26 mitotypes based on mDNA) could be accurately modeled (AUC > 0.9), and they responded differently to environmental drivers. This suggests that rapid evolutionary change may be underway in the Africanized bees, allowing the bees to spread into new areas and extending their total range. Protecting native species and ecosystems may benefit from risk maps of harmful invasive species, hybrids, and genotypes.

  5. Big Five Personality Traits and the General Factor of Personality as Moderators of Stress and Coping Reactions Following an Emergency Alarm on a Swiss University Campus.

    Science.gov (United States)

    Hengartner, Michael P; van der Linden, Dimitri; Bohleber, Laura; von Wyl, Agnes

    2017-02-01

    We conducted an online survey including 306 participants aged 18-64 years to assess the general factor of personality (GFP) and Big Five personality traits in relation to individual stress and coping reactions following a shooting emergency alarm at a Swiss university campus. Although the emergency eventually turned out to be a false alarm, various witnesses showed pronounced distress owing to a vast police operation. The GFP structure was replicated using two alternative modelling approaches. Neuroticism related substantially to acute fear and traumatic distress as well as to more enduring maladaptive coping. Agreeableness was negatively associated with the coping strategy of medication use, whereas both agreeableness and conscientiousness related positively to social activity following the emergency. The GFP related moderately to peri-traumatic distress and showed a substantial negative association with medication use and a strong positive association with social activity. In conclusion, both the GFP and Big Five traits significantly moderate stress responses following a stressful life event. The GFP predominantly relates to socially adaptive coping, whereas in particular neuroticism accounts for acute stress reactions such as fear and traumatic distress. These findings support the notion that personality influences how persons react in the face of adversity. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. First-Order Hybrid Logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Hybrid logic is an extension of modal logic which allows us to refer explicitly to points of the model in the syntax of formulas. It is easy to justify interest in hybrid logic on applied grounds, with the usefulness of the additional expressive power. For example, when reasoning about time one...... often wants to build up a series of assertions about what happens at a particular instant, and standard modal formalisms do not allow this. What is less obvious is that the route hybrid logic takes to overcome this problem often actually improves the behaviour of the underlying modal formalism....... For example, it becomes far simpler to formulate proof-systems for hybrid logic, and completeness results can be proved of a generality that is simply not available in modal logic. That is, hybridization is a systematic way of remedying a number of known deficiencies of modal logic. First-order hybrid logic...

  7. Comparison of Occupational Stress in Response to Challenging Behaviours between General and Special Education Primary Teachers in Northern Italy

    Science.gov (United States)

    Pepe, A.; Addimando, L.

    2013-01-01

    In the Italian education system, pupils with special education needs (SEN) are fully included in mainstream education and receive extra support from special education teachers (SET). Starting from this point, it is reasonable to expect some degree of difference between special education teachers (SETs) and general education teachers (GETs) in term…

  8. Hybrid reactors

    International Nuclear Information System (INIS)

    Moir, R.W.

    1980-01-01

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of 233 U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m -2 , and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid

  9. Simulating carbon dioxide exchange rates of deciduous tree species: evidence for a general pattern in biochemical changes and water stress response.

    Science.gov (United States)

    Reynolds, Robert F; Bauerle, William L; Wang, Ying

    2009-09-01

    Deciduous trees have a seasonal carbon dioxide exchange pattern that is attributed to changes in leaf biochemical properties. However, it is not known if the pattern in leaf biochemical properties - maximum Rubisco carboxylation (V(cmax)) and electron transport (J(max)) - differ between species. This study explored whether a general pattern of changes in V(cmax), J(max), and a standardized soil moisture response accounted for carbon dioxide exchange of deciduous trees throughout the growing season. The model MAESTRA was used to examine V(cmax) and J(max) of leaves of five deciduous trees, Acer rubrum 'Summer Red', Betula nigra, Quercus nuttallii, Quercus phellos and Paulownia elongata, and their response to soil moisture. MAESTRA was parameterized using data from in situ measurements on organs. Linking the changes in biochemical properties of leaves to the whole tree, MAESTRA integrated the general pattern in V(cmax) and J(max) from gas exchange parameters of leaves with a standardized soil moisture response to describe carbon dioxide exchange throughout the growing season. The model estimates were tested against measurements made on the five species under both irrigated and water-stressed conditions. Measurements and modelling demonstrate that the seasonal pattern of biochemical activity in leaves and soil moisture response can be parameterized with straightforward general relationships. Over the course of the season, differences in carbon exchange between measured and modelled values were within 6-12 % under well-watered conditions and 2-25 % under water stress conditions. Hence, a generalized seasonal pattern in the leaf-level physiological change of V(cmax) and J(max), and a standardized response to soil moisture was sufficient to parameterize carbon dioxide exchange for large-scale evaluations. Simplification in parameterization of the seasonal pattern of leaf biochemical activity and soil moisture response of deciduous forest species is demonstrated. This

  10. Generalized Anxiety Disorder (GAD) and Comorbid Major Depression with GAD Are Characterized by Enhanced Nitro-oxidative Stress, Increased Lipid Peroxidation, and Lowered Lipid-Associated Antioxidant Defenses.

    Science.gov (United States)

    Maes, Michael; Bonifacio, Kamila Landucci; Morelli, Nayara Rampazzo; Vargas, Heber Odebrecht; Moreira, Estefânia Gastaldello; St Stoyanov, Drozdstoy; Barbosa, Décio Sabbatini; Carvalho, André F; Nunes, Sandra Odebrecht Vargas

    2018-05-07

    Accumulating evidence shows that nitro-oxidative pathways play an important role in the pathophysiology of major depressive disorder (MDD) and bipolar disorder (BD) and maybe anxiety disorders. The current study aims to examine superoxide dismutase (SOD1), catalase, lipid hydroperoxides (LOOH), nitric oxide metabolites (NOx), advanced oxidation protein products (AOPP), malondialdehyde (MDA), glutathione (GSH), paraoxonase 1 (PON1), high-density lipoprotein cholesterol (HDL), and uric acid (UA) in participants with and without generalized anxiety disorder (GAD) co-occurring or not with BD, MDD, or tobacco use disorder. Z unit-weighted composite scores were computed as indices of nitro-oxidative stress driving lipid and protein oxidation. SOD1, LOOH, NOx, and uric acid were significantly higher and HDL and PON1 significantly lower in participants with GAD than in those without GAD. GAD was more adequately predicted by increased SOD + LOOH + NOx and lowered HDL + PON1 composite scores. Composite scores of nitro-oxidative stress coupled with aldehyde and AOPP production were significantly increased in participants with comorbid GAD + MDD as compared with all other study groups, namely MDD, GAD + BD, BD, GAD, and healthy controls. In conclusion, GAD is characterized by increased nitro-oxidative stress and lipid peroxidation and lowered lipid-associated antioxidant defenses, while increased uric acid levels in GAD may protect against aldehyde production and protein oxidation. This study suggests that increased nitro-oxidative stress and especially increased SOD1 activity, NO production, and lipid peroxidation as well as lowered HDL-cholesterol and PON1 activity could be novel drug targets for GAD especially when comorbid with MDD.

  11. Heart rate and autonomic response to stress after experimental induction of worry versus relaxation in healthy, high-worry, and generalized anxiety disorder individuals.

    Science.gov (United States)

    Fisher, Aaron J; Newman, Michelle G

    2013-04-01

    Generalized anxiety disorder (GAD) is the most commonly occurring anxiety disorder and has been related to cardiovascular morbidity such as cardiac ischemia, sudden cardiac death, and myocardial infarction. Both GAD and its cardinal symptom - worry - have been shown to promote muted physiological reactivity in response to laboratory and ecological stressors. Importantly, no study to date has examined the concurrent and relative contributions of trait and state worry within healthy controls, (non-clinical) high trait-worry controls, and GAD participants. The present study examined heart rate (HR), respiratory sinus arrhythmia (RSA), and salivary alpha-amylase (sAA) responses to laboratory stress during and following the experimental induction of worry versus relaxation in healthy controls (n=42), high trait worriers (n=33) and participants with GAD (n=76). All groups exhibited increased HR and decreased RSA in response to the stressor, with no differences by condition. Baseline sAA significantly moderated HR and RSA reactivity, such that higher sAA predicted greater increases in HR and decreases in RSA. There was a significant group by baseline sAA interaction such that in GAD, higher baseline sAA predicted decreased change in sAA during stress, whereas higher baseline sAA predicted greater sAA change in healthy controls. High-worry controls fell non-significantly between these groups. The present study provides additional evidence for the effect of worry on diminished HR stress response and points to possible suppression of adrenergic sympathetic stress responses in GAD. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Selecting the optimal synthesis parameters of InP/CdxZn1-xSe quantum dots for a hybrid remote phosphor white LED for general lighting applications.

    Science.gov (United States)

    Ryckaert, Jana; Correia, António; Tessier, Mickael D; Dupont, Dorian; Hens, Zeger; Hanselaer, Peter; Meuret, Youri

    2017-11-27

    Quantum dots can be used in white LEDs for lighting applications to fill the spectral gaps in the combined emission spectrum of the blue pumping LED and a broad band phosphor, in order to improve the source color rendering properties. Because quantum dots are low scattering materials, their use can also reduce the amount of backscattered light which can increase the overall efficiency of the white LED. The absorption spectrum and narrow emission spectrum of quantum dots can be easily tuned by altering their synthesis parameters. Due to the re-absorption events between the different luminescent materials and the light interaction with the LED package, determining the optimal quantum dot properties is a highly non-trivial task. In this paper we propose a methodology to select the optimal quantum dot to be combined with a broad band phosphor in order to realize a white LED with optimal luminous efficacy and CRI. The methodology is based on accurate and efficient simulations using the extended adding-doubling approach that take into account all the optical interactions. The method is elaborated for the specific case of a hybrid, remote phosphor white LED with YAG:Ce phosphor in combination with InP/CdxZn 1-x Se type quantum dots. The absorption and emission spectrum of the quantum dots are generated in function of three synthesis parameters (core size, shell size and cadmium fraction) by a semi-empirical 'quantum dot model' to include the continuous tunability of these spectra. The sufficiently fast simulations allow to scan the full parameter space consisting of these synthesis parameters and luminescent material concentrations in terms of CRI and efficacy. A conclusive visualization of the final performance allows to make a well-considered trade-off between these performance parameters. For the hybrid white remote phosphor LED with YAG:Ce and InP/CdxZn 1-x Se quantum dots a CRI Ra = 90 (with R9>50) and an overall efficacy of 110 lm/W is found.

  13. SPANDE, Stress Analysis of General Space-frame and Pipework. SPATAM, Tilt Angle Calculation of Framework for Program SPANDE

    International Nuclear Information System (INIS)

    Davies, D.C.; Enderby, J.A.; Knowles, J.A.

    1984-01-01

    1 - Nature of physical problem solved: The programme is intended to analyse almost any type of space-frame. Members of the frame may be either straight or of constant curvature between nodes provided that, in the case of curved members, one of the principal axes of the cross-section of the member lies in the same plane as the member. Loading may comprise concentrated loads, distributed loads, thermal loads or may take the form of specified displacements. The programme calculates the forces and moments in all the members of the framework, the reactions at all external restraints and the displacements of all the nodes. For pipework problems, the maximum stress difference in the pipe, calculated in accordance with the code of practice, is also quoted. 2 - Method of solution: The framework is solved by displacement methods involving stiffness matrices, making it possible to analyse space-frames with virtually any number of redundancies. 3 - Restrictions on the complexity of the problem: For ICL 4/70, the framework is limited to 1000 nodes, 2000 members, 100 different member types or 200 specified nodal displacements

  14. Effectiveness of a Minimal Intervention for Stress-related mental disorders with Sick leave (MISS; study protocol of a cluster randomised controlled trial in general practice [ISRCTN43779641

    Directory of Open Access Journals (Sweden)

    van Marwijk Harm WJ

    2006-05-01

    Full Text Available Abstract Background The main aims of this paper are to describe the setting and design of a Minimal Intervention in general practice for Stress-related mental disorders in patients on Sick leave (MISS, as well as to ascertain the study complies with the requirements for a cluster randomised controlled trial (RCT. The potential adverse consequences of sick leave due to Stress-related Mental Disorders (SMDs are extensive, but often not recognised. Since most people having SMDs with sick leave consult their general practitioner (GP at an early stage, a tailored intervention given by GPs is justified. We provide a detailed description of the MISS; that is more accurate assessment, education, advice and monitoring to treat SMDs in patients on sick leave. Our hypothesis is that the MISS will be more effective compared to the usual care, in reducing days of sick leave of these patients. Methods The design is a pragmatic RCT. Randomisation is at the level of GPs. They received the MISS-training versus no training, in order to compare the MISS vs. usual care at patient level. Enrolment of patients took place after screening in the source population, that comprised 20–60 year old primary care attendees. Inclusion criteria were: moderately elevated distress levels, having a paid job and sick leave for no longer than three months. There is a one year follow up. The primary outcome measure is lasting full return to work. Reduction of SMD- symptoms is one of the secondary outcome measures. Forty-six GPs and 433 patients agreed to participate. Discussion In our study design, attention is given to the practical application of the requirements for a pragmatic trial. The results of this cluster RCT will add to the evidence about treatment options in general practice for SMDs in patients on sick leave, and might contribute to a new and appropriate guideline. These results will be available at the end of 2006.

  15. Proposed research on class I components to test a general approach to accelerated aging under combined stress environments

    International Nuclear Information System (INIS)

    Gillen, K.T.; Salazar, E.A.; Frank, C.W.

    1977-04-01

    This report summarizes research on the aging of Class I components in environments representative of nuclear power plants. It discusses Class IE equipment used in nuclear power plants, typical environments encountered by Class IE components, and aging techniques used to qualify this equipment. General discussions of radiation chemistry of polymers and accelerated aging techniques are also included. Based on the inadequacies of present aging techniques for Class IE equipment, a proposal for an experimental program on electrical cables is presented. One of the main purposes of the proposed work is to obtain relevant data in two areas of particular concern--the effect of radiation dose rate on polymer degradation, and the importance of synergism for combined thermal and radiation environments. A new model that allows combined environment accelerated aging to be carried out is introduced, and it is shown how the experimental data to be generated can be used to test this model

  16. Intimate partner violence and ways of coping with stress: cross-sectional survey of female patients in Russian general practice.

    Science.gov (United States)

    Lokhmatkina, Natalia V; Agnew-Davies, Roxane; Costelloe, Ceire; Kuznetsova, Olga Yu; Nikolskaya, Irina M; Feder, Gene S

    2015-04-01

    Despite World Health Organization guidelines on health service responses to intimate partner violence (IPV) against women general practitioners (GPs) often overlook the problem. Training on IPV addresses GPs' barriers to asking women patients about abuse and responding appropriately. One of the barriers is stereotype of women as passive victims. Little is known about coping behaviour of women patients with a history of IPV. The objectives are (i) to compare problem- and emotion-focused coping used by patients who have experienced IPV with those who have not; (ii) to examine whether greater coping resources (health, education, employment and income) would be associated with more problem-focused coping. The Russian Ways of Coping Questionnaire was administered to every fifth woman who participated in a cross-sectional survey on IPV prevalence in 24 St Petersburg general practices. Linear regression was used (n = 159) to test associations between life-time IPV, coping resources and ways of coping. Mean problem-focused coping scores were 0.2-4.7 units higher in those patients who have experienced IPV compared with those who have not [95% confidence interval (CI): -4.2, 11.9; P = 0.16-0.92], while mean emotion-focused coping scores were 2.5-4.2 units higher (95% CI: -3.0, 11.0; P = 0.12-0.57). After adjustment for coping resources there was no evidence for an association between IPV and problem-focused coping. Patients who have experienced IPV use as much problem-focused and emotion-focused coping, as those patients who have not experienced IPV. These findings should be incorporated into training on IPV to address GPs' stereotypes towards patients who have experienced IPV. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Evaluation of Inter-Specific Hybrid of P. atlantica and P. vera L. cv. ‘Badami - Riz-e-Zarand’ as Pistachio rootstock to Salinity Stress According to Some Growth Indices and Eco-physiological and Biochemical Parameters

    Directory of Open Access Journals (Sweden)

    Hamid Reza Karimi

    2014-08-01

    Full Text Available In order to evaluate the inter-specific hybrid of P. atlantica Desf. and P. vera L. cv. ‘Badami- Riz-e- Zarand’ to salinity stress, a factorial experiment was conducted based on completely randomized design with 0, 60 and 120 mM of salinity levels of sodium chloride, calcium chloride and magnesium chloride (3:2:1 with four replications on ‘Qazvini’, ‘Badami-Riz-e-Zarand’ and inter-specific of P. atlantica Ч P. vera cv. ‘Badami-Rize-Zarand’ rootstocks of pistachio. The results showed that salinity has increased proline content of leaves. Chlorophyll index, relative water content of leaf, leaf area, shoot and root fresh and dry weight, stem diameter and number of leaves were decreased by increasing salinity. Rootstocks responded differently to salinity, so that the most reduction in chlorophyll index, leaf area and leaf number were observed in ‘Badami-Riz-e-Zarand’ rootstock and the least reduction was observed in the hybrid.

  18. Hybrid strategies in nanolithography

    Energy Technology Data Exchange (ETDEWEB)

    Saavedra, Hector M; Mullen, Thomas J; Zhang Pengpeng; Dewey, Daniel C; Claridge, Shelley A; Weiss, Paul S [Department of Chemistry, The Pennsylvania State University, University Park, PA 16802 (United States)], E-mail: psw@cnsi.ucla.edu

    2010-03-15

    Hybrid nanoscale patterning strategies combine the registration and addressability of conventional lithographic techniques with the chemical and physical functionality enabled by intermolecular, electrostatic and/or biological interactions. This review aims to highlight and to provide a comprehensive description of recent developments in hybrid nanoscale patterning strategies that enhance existing lithographic techniques or can be used to fabricate functional chemical patterns that interact with their environment. These functional structures create new capabilities, such as the fabrication of physicochemical surfaces that can recognize and capture analytes from complex liquid or gaseous mixtures. The nanolithographic techniques we describe can be classified into three general areas: traditional lithography, soft lithography and scanning-probe lithography. The strengths and limitations of each hybrid patterning technique will be discussed, along with the current and potential applications of the resulting patterned, functional surfaces.

  19. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available mixed short sisal/glass hybrid fibre reinforced low density polyethylene composites was investigated by Kalaprasad et al [25].Chemical surface modifications such as alkali, acetic anhydride, stearic acid, permanganate, maleic anhydride, silane...

  20. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  1. Co-occurrence of and remission from general anxiety, depression, and posttraumatic stress disorder symptoms after acute lung injury: a 2-year longitudinal study

    Science.gov (United States)

    Bienvenu, O. Joseph; Colantuoni, Elizabeth; Mendez-Tellez, Pedro A.; Shanholtz, Carl; Dennison-Himmelfarb, Cheryl R.; Pronovost, Peter J.; Needham, Dale M.

    2014-01-01

    Objective To evaluate the co-occurrence, and predictors of remission, of general anxiety, depression, and posttraumatic stress disorder (PTSD) symptoms during 2-year follow-up in survivors of acute lung injury (ALI) treated in an intensive care unit (ICU). Design, Setting, and Patients This prospective cohort study enrolled 520 patients from 13 medical and surgical ICUs in 4 hospitals, with follow-up at 3, 6, 12, and 24 months post-ALI. Measurements and Main Results The outcomes of interest were measured using the Hospital Anxiety and Depression Scale (HADS) anxiety and depression subscales (scores ≥8 indicating substantial symptoms) and the Impact of Event Scale-Revised (IESR, scores ≥1.6 indicating substantial PTSD symptoms). Of the 520 enrolled patients, 274 died before 3-month follow-up; 186/196 consenting survivors (95%) completed at least one HADS and IESR assessment during 2-year follow-up, and most completed multiple assessments. Across follow-up time points, the prevalence of supra-threshold general anxiety, depression, and PTSD symptoms ranged from 38–44%, 26–33%, and 22–24%, respectively; more than half of the patients had supra-threshold symptoms in at least one domain during 2-year follow-up. The majority (59%) of survivors with any supra-threshold symptoms were above threshold for 2 or more types of symptoms (i.e., of general anxiety, depression, and/or PTSD). In fact, the most common pattern involved simultaneous general anxiety, depression, and PTSD symptoms. Most patients with general anxiety, depression, or PTSD symptoms during 2-year follow-up had supra-threshold symptoms at 24-month (last) follow-up. Higher SF-36 physical functioning domain scores at the prior visit were associated with a greater likelihood of remission from general anxiety and PTSD symptoms during follow-up. Conclusions The majority of ALI survivors had clinically significant general anxiety, depressive, or PTSD symptoms, and these symptoms tended to co-occur across

  2. Construct validity of the psychological general well being index (PGWBI in a sample of patients undergoing treatment for stress-related exhaustion: a rasch analysis

    Directory of Open Access Journals (Sweden)

    Lundgren-Nilsson Åsa

    2013-01-01

    Full Text Available Abstract Purpose The Psychological General Well Being Index (PGWBI is a widely used scale across many conditions. Over time issues have been raised about the dimensional structure of the scale, and it has not yet been subjected to scrutiny by modern Psychometric approaches. The current study thus evaluates the PGWBI with Rasch- and factor analysis. Methods Consecutive patients recruited to a tertiary stress clinic were administered the PGBWI as part of routine clinical assessment at baseline and three months. Data from the scale was subjected to Factor Analyses and to Rasch analysis. In both cases adjustments for local independence violations were allowed. Results 179 patients were recruited, with a mean age of 43 years, and of whom 70% were female. An initial Confirmatory Factor Analysis (CFA with baseline data failed, but the modification indices also indicated considerable levels of local dependency requiring errors to be correlated. An EFA highlighted positive and negative effect domains. Rasch analysis confirmed that fit of data to the model was influenced by local dependency, and that in practice if the items from the six underlying domains were treated as six ‘super’ items, the scale was shown to measure one dominant construct of well being. An interval scale transformation was therefore possible. A significant improvement in well-being was observed over a three month period. Conclusion The PGWBI scale has satisfactory internal construct validity when tested with modern psychometric techniques, using data obtained from patients treated for stress-related exhaustion. The instrument has qualities that make it suitable also for monitoring well-being during interventions for stress-related exhaustion/clinical burnout.

  3. Plants in water-controlled ecosystems: active role in hydrologic processes and response to water stress. I. Scope and general outline

    Science.gov (United States)

    Rodriguez-Iturbe, I.; Porporato, A.; Laio, F.; Ridolfi, L.

    This series of four papers studies the complex dynamics of water-controlled ecosystems from the hydro-ecological point of view [e.g., I. Rodriguez-Iturbe, Water Resour. Res. 36 (1) (2000) 3-9]. After this general outline, the role of climate, soil, and vegetation is modeled in Part II [F. Laio, A. Porporato, L. Ridolfi, I. Rodriguez-Iturbe, Adv. Water Res. 24 (7) (2001) 707-723] to investigate the probabilistic structure of soil moisture dynamics and the water balance. Particular attention is given to the impact of timing and amount of rainfall, plant physiology, and soil properties. From the statistical characterization of the crossing properties of arbitrary levels of soil moisture, Part III develops an expression for vegetation water stress [A. Porporato, F. Laio, L. Ridolfi, I. Rodriguez-Iturbe, Adv. Water Res. 24 (7) (2001) 725-744]. This measure of stress is then employed to quantify the response of plants to soil moisture deficit as well as to infer plant suitability to given environmental conditions and understand some of the reasons for possible coexistence of different species. Detailed applications of these concepts are developed in Part IV [F. Laio, A. Porporato, C.P. Fernandez-Illescas, I. Rodriguez-Iturbe, Adv. Water Res. 24 (7) (2001) 745-762], where we investigate the dynamics of three different water-controlled ecosystems.

  4. Depression, Somatization, and Posttraumatic Stress Disorder in Children Born of Occupation After World War II in Comparison With a General Population.

    Science.gov (United States)

    Kaiser, Marie; Kuwert, Philipp; Braehler, Elmar; Glaesmer, Heide

    2015-10-01

    At the end of World War II and during the first decade after the war, roughly 200,000 children were fathered in intimate contacts between German women and foreign soldiers. The experiences of these German occupation children (GOC) have been so far described in case reports and from historical perspective only. Research on psychosocial consequences of growing up as a GOC has been missing so far. This study examined traumatic experiences, posttraumatic stress disorder, somatization, and depression in GOC (N = 146) using self-report instruments: Posttraumatic Diagnostic Scale and Patient Health Questionnaire. Findings have then been compared with a representative birth cohort-matched sample from the German general population (N = 977). German occupation children showed significantly higher prevalence rates of most traumatic experiences, higher point prevalence rates of full and partial posttraumatic stress disorder, depression, and somatization than the control group. In summary, GOC often grew up under difficult conditions (e.g., poverty, single mothers, and stigmatization). Even decades later, they showed higher rates of different mental disorders and higher comorbidity. These findings underline the complex and long-term impact of their burdened social, financial, and familial conditions. The results underpin the importance of conceptualizing occupation children as a vulnerable group in postconflict settings.

  5. Discovery and Function of a General Core Hormetic Stress Response in E. coli Induced by Sublethal Concentrations of Antibiotics.

    Science.gov (United States)

    Mathieu, Aurélie; Fleurier, Sébastien; Frénoy, Antoine; Dairou, Julien; Bredeche, Marie-Florence; Sanchez-Vizuete, Pilar; Song, Xiaohu; Matic, Ivan

    2016-09-27

    A better understanding of the impact of antibiotics on bacteria is required to increase the efficiency of antibiotic treatments and to slow the emergence of resistance. Using Escherichia coli, we examined how bacteria exposed to sublethal concentrations of ampicillin adjust gene expression patterns and metabolism to simultaneously deal with the antibiotic-induced damage and maintain rapid growth. We found that the treated cells increased energy production, as well as translation and macromolecular repair and protection. These responses are adaptive, because they confer increased survival not only to lethal ampicillin treatment but also to non-antibiotic lethal stresses. This robustness is modulated by nutrient availability. Because different antibiotics and other stressors induce the same set of responses, we propose that it constitutes a general core hormetic stress response. It is plausible that this response plays an important role in the robustness of bacteria exposed to antibiotic treatments and constant environmental fluctuations in natural environments. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. Reliability estimation of a N- M-cold-standby redundancy system in a multicomponent stress-strength model with generalized half-logistic distribution

    Science.gov (United States)

    Liu, Yiming; Shi, Yimin; Bai, Xuchao; Zhan, Pei

    2018-01-01

    In this paper, we study the estimation for the reliability of a multicomponent system, named N- M-cold-standby redundancy system, based on progressive Type-II censoring sample. In the system, there are N subsystems consisting of M statistically independent distributed strength components, and only one of these subsystems works under the impact of stresses at a time and the others remain as standbys. Whenever the working subsystem fails, one from the standbys takes its place. The system fails when the entire subsystems fail. It is supposed that the underlying distributions of random strength and stress both belong to the generalized half-logistic distribution with different shape parameter. The reliability of the system is estimated by using both classical and Bayesian statistical inference. Uniformly minimum variance unbiased estimator and maximum likelihood estimator for the reliability of the system are derived. Under squared error loss function, the exact expression of the Bayes estimator for the reliability of the system is developed by using the Gauss hypergeometric function. The asymptotic confidence interval and corresponding coverage probabilities are derived based on both the Fisher and the observed information matrices. The approximate highest probability density credible interval is constructed by using Monte Carlo method. Monte Carlo simulations are performed to compare the performances of the proposed reliability estimators. A real data set is also analyzed for an illustration of the findings.

  7. The influence of parental care and overprotection, neuroticism and adult stressful life events on depressive symptoms in the general adult population.

    Science.gov (United States)

    Ono, Yasuyuki; Takaesu, Yoshikazu; Nakai, Yukiei; Ichiki, Masahiko; Masuya, Jiro; Kusumi, Ichiro; Inoue, Takeshi

    2017-08-01

    The quality of parenting, neuroticism, and adult stressful life events are reportedly associated with depressive symptoms. However, previous studies have not examined the complex interaction between these three factors. In this study, we hypothesized that the quality of parenting (care and overprotection) acts on depressive symptoms through 'neuroticism' and the appraisal of adult stressful life events, and this hypothesis was verified by structural equation modeling. Four hundred one participants from the general adult population were studied using the following self-administered questionnaire surveys: Patient Health Questionnaire-9 (PHQ-9), Parental Bonding Instrument (PBI), neuroticism subscale of the short version of the Eysenck Personality Questionnaire-revised (EPQ-R), and Life Experiences Survey (LES). The data were analyzed with single and multiple regression analyses and covariance structure analyses. In the covariance structure analysis, neuroticism scores and negative change scores on the LES acted on the depressive symptoms (PHQ-9 scores) directly, but care or overprotection in childhood on the PBI did not act on them directly. Low care and high overprotection of the PBI increased depressive symptoms and negative change scores on the LES through enhanced neuroticism, which is regarded as a mediator in these effects. The subjects of this study were nonclinical volunteers; the findings might not be generalizable to psychiatric patients. This research showed that low care and high overprotection of maternal and paternal parenting in childhood influence depressive symptoms indirectly through enhanced neuroticism in general adults. These findings suggest that neuroticism mediates the long-term effect of the quality of parenting on depression in adulthood. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. The Mars Dust Cycle: Investigating the Effects of Radiatively Active Water Ice Clouds on Surface Stresses and Dust Lifting Potential with the NASA Ames Mars General Circulation Model

    Science.gov (United States)

    Kahre, Melinda A.; Hollingsworth, Jeffery

    2012-01-01

    The dust cycle is a critically important component of Mars' current climate system. Dust is present in the atmosphere of Mars year-round but the dust loading varies with season in a generally repeatable manner. Dust has a significant influence on the thermal structure of the atmosphere and thus greatly affects atmospheric circulation. The dust cycle is the most difficult of the three climate cycles (CO2, water, and dust) to model realistically with general circulation models. Until recently, numerical modeling investigations of the dust cycle have typically not included the effects of couplings to the water cycle through cloud formation. In the Martian atmosphere, dust particles likely provide the seed nuclei for heterogeneous nucleation of water ice clouds. As ice coats atmospheric dust grains, the newly formed cloud particles exhibit different physical and radiative characteristics. Thus, the coupling between the dust and water cycles likely affects the distributions of dust, water vapor and water ice, and thus atmospheric heating and cooling and the resulting circulations. We use the NASA Ames Mars GCM to investigate the effects of radiatively active water ice clouds on surface stress and the potential for dust lifting. The model includes a state-of-the-art water ice cloud microphysics package and a radiative transfer scheme that accounts for the radiative effects of CO2 gas, dust, and water ice clouds. We focus on simulations that are radiatively forced by a prescribed dust map, and we compare simulations that do and do not include radiatively active clouds. Preliminary results suggest that the magnitude and spatial patterns of surface stress (and thus dust lifting potential) are substantial influenced by the radiative effects of water ice clouds.

  9. Genetic basis to hybrid inviability is more complex than hybrid male sterility in Caenorhabditis nematodes.

    Science.gov (United States)

    Bundus, Joanna D; Wang, Donglin; Cutter, Asher D

    2018-04-07

    Hybrid male sterility often evolves before female sterility or inviability of hybrids, implying that the accumulation of divergence between separated lineages should lead hybrid male sterility to have a more polygenic basis. However, experimental evidence is mixed. Here, we use the nematodes Caenorhabditis remanei and C. latens to characterize the underlying genetic basis of asymmetric hybrid male sterility and hybrid inviability. We demonstrate that hybrid male sterility is consistent with a simple genetic basis, involving a single X-autosome incompatibility. We also show that hybrid inviability involves more genomic compartments, involving diverse nuclear-nuclear incompatibilities, a mito-nuclear incompatibility, and maternal effects. These findings demonstrate that male sensitivity to genetic perturbation may be genetically simple compared to hybrid inviability in Caenorhabditis and motivates tests of generality for the genetic architecture of hybrid incompatibility across the breadth of phylogeny.

  10. Effect of the Volume Fraction of Jute Fiber on the Interlaminar Shear Stress and Tensile Behavior Characteristics of Hybrid Glass/Jute Fiber Reinforced Polymer Composite Bar for Concrete Structures

    Directory of Open Access Journals (Sweden)

    Chan-Gi Park

    2016-01-01

    Full Text Available Hybrid glass/jute fiber reinforced polymer (HGJFRP composite bars were manufactured for concrete structures, and their interlaminar shear stress and tensile performance were evaluated. HGJFRP composite bars were manufactured using a combination of pultrusion and braiding processes. Jute fiber was surface-treated with a silane coupling agent. The mixing ratio of the fiber to the vinyl ester used in the HGJFRP composite bars was 7 : 3. Jute fiber was used to replace glass fiber in proportions of 0, 30, 50, 70, and 100%. The interlaminar shear stress decreased as the proportion of jute fiber increased. Fractures appeared due to delamination between the surface-treated component and the main part of the HGJFRP composite bar. Tensile load-strain curves with 50% jute fiber exhibited linear behavior. With a jute fiber volume fraction of 70%, some plastic deformation occurred. A jute fiber mixing ratio of 100% resulted in a display of linear elastic brittle behavior from the fiber; however, when the surface of the fiber was coated with poly(vinyl acetate, following failure, the jute fiber exhibited partial load resistance. The tensile strength decreased as the jute fiber content increased; however, the tensile strength did not vary linearly with jute fiber content.

  11. Stomatal characteristics of Eucalyptus grandis clonal hybrids in ...

    African Journals Online (AJOL)

    This study describes the stomatal response occurring during water stress and subsequent recovery of three Eucalyptus grandis clonal hybrids. The aim was to investigate the degree to which stomatal conductance (gs) and stomatal density differ between the clonal hybrids across seasons and in response to water stress.

  12. A general salt-templating method to fabricate vertically aligned graphitic carbon nanosheets and their metal carbide hybrids for superior lithium ion batteries and water splitting.

    Science.gov (United States)

    Zhu, Jixin; Sakaushi, Ken; Clavel, Guylhaine; Shalom, Menny; Antonietti, Markus; Fellinger, Tim-Patrick

    2015-04-29

    The synthesis of vertically aligned functional graphitic carbon nanosheets (CNS) is challenging. Herein, we demonstrate a general approach for the fabrication of vertically aligned CNS and metal carbide@CNS composites via a facile salt templating induced self-assembly. The resulting vertically aligned CNS and metal carbide@CNS structures possess ultrathin walls, good electrical conductivity, strong adhesion, excellent structural robustness, and small particle size. In electrochemical energy conversion and storage such unique features are favorable for providing efficient mass transport as well as a large and accessible electroactive surface. The materials were tested as electrodes in a lithium ion battery and in electrochemical water splitting. The vertically aligned nanosheets exhibit remarkable lithium ion storage properties and, concurrently, excellent properties as electrocatalysts for hydrogen evolution.

  13. Development of a Generalized Version of the Poisson-Nernst-Planck Equations Using the Hybrid Mixture Theory: Presentation of 2D Numerical Examples

    DEFF Research Database (Denmark)

    Johannesson, Björn

    2010-01-01

    A numerical scheme for the transient solution of generalized version of the Poisson-Nernst-Planck equations is presented. The finite element method is used to establish the coupled non-linear matrix system of equations capable of solving the present problem iteratively. The Poisson......-scale and that it includes the volume fractions of phases in its structure. The background to the Poisson-Nernst-Planck equations can by the HMT approach be described by using the postulates of mass conservation of constituents together with the Gauss’ law used together with consistent constitutive laws. The HMT theory......-Nernst-Planck equations represent a set of diffusion equations for charged species, i.e. dissolved ions. These equations are coupled to the ‘internally’ induced electrical field and to the velocity field of the fluid. The Nernst-Planck equations describing the diffusion of the ionic species and the Gauss’ law in used are...

  14. Gene expression and yeast two-hybrid studies of transcription factors mediating drought stress response in root tissues of chickpea (Cicer arietinum L.

    Directory of Open Access Journals (Sweden)

    Abirami eRamalingam

    2015-12-01

    Full Text Available Drought stress has been one of the serious constraints affecting chickpea productivity to a great extent. Genomic assisted breeding in chickpea has been effective in providing a yield advantage of up to 24 %, thus having a potential to accelerate breeding precisely and efficiently. In order to do so, understanding the molecular mechanisms for drought tolerance and identification of candidate genes are crucial. Transcription factors (TFs have important roles in the regulation of plant stress related genes. In this context, quantitative real time-PCR (qRT-PCR was used to study the differential gene expression of selected TFs, identified from large-scale gene expression analysis, in contrasting drought responsive genotypes. Root tissues of ICC 4958 (tolerant, ICC 1882 (sensitive, JG 11 (elite and JG 11+ (introgression line were used for the study. Subsequently, a candidate single repeat MYB gene (1R-MYB that was remarkably induced in the drought tolerant genotypes under drought stress was cloned and subjected to Y2H analysis by screening a root cDNA library. The protein-protein interaction study identified three interacting peptides, a galactinol-sucrose galactosyltransferase 2, a CBL (Calcineurin B-like-interacting serine/threonine-protein kinase 25 and an ABA responsive 17-like, which were confirmed by the co-transformation of candidate plasmids in yeast. These findings provide preliminary insights into the ability of 1R-MYB TF to co-regulate drought tolerance mechanism in chickpea roots.

  15. Perspectives in the development of hybrid bifunctional antitumour agents.

    Science.gov (United States)

    Musso, Loana; Dallavalle, Sabrina; Zunino, Franco

    2015-08-15

    In spite of the development of a large number of novel target-specific antitumour agents, the single-agent therapy is in general not able to provide an effective durable control of the malignant process. The limited efficacy of the available agents (both conventional cytotoxic and novel target-specific) reflects not only the expression of defence mechanisms, but also the complexity of tumour cell alterations and the redundancy of survival pathways, thus resulting in tumour cell ability to survive under stress conditions. A well-established strategy to improve the efficacy of antitumour therapy is the rational design of drug combinations aimed at achieving synergistic effects and overcoming drug resistance. An alternative strategy could be the use of agents designed to inhibit simultaneously multiple cellular targets relevant to tumour growth/survival. Among these novel agents are hybrid bifunctional drugs, i.e. compounds resulting by conjugation of different drugs or containing the pharmocophores of different drugs. This strategy has been pursued using various conventional or target-specific agents (with DNA damaging agents and histone deacetylase inhibitors as the most exploited compounds). A critical overview of the most representative compounds is provided with emphasis on the HDAC inhibitor-based hybrid agents. In spite of some promising results, the actual pharmacological advantages of the hybrid agents remain to be defined. This commentary summarizes the recent advances in this field and highlights the pharmacological basis for a rational design of hybrid bifunctional agents. Copyright © 2015. Published by Elsevier Inc.

  16. Hybrid stars

    Indian Academy of Sciences (India)

    Hybrid stars. AsHOK GOYAL. Department of Physics and Astrophysics, University of Delhi, Delhi 110 007, India. Abstract. Recently there have been important developments in the determination of neutron ... number and the electric charge. ... available to the system to rearrange concentration of charges for a given fraction of.

  17. Stress and stressors in the clinical environment: a comparative study of fourth-year student nurses and newly qualified general nurses in Ireland.

    LENUS (Irish Health Repository)

    Suresh, Patricia

    2013-03-01

    To measure and compare the perceived levels of job-related stress and stressors of newly qualified nurses and fourth-year student nurses in the clinical environment and to explore the participants\\' views on stress and stressors.

  18. How Is Examination Stress Experienced by Secondary Students Preparing for Their General Certificate of Secondary Education Examinations and How Can It Be Explained?

    Science.gov (United States)

    Putwain, David William

    2011-01-01

    High stakes examinations have been identified as a significant source of stress for secondary school students; however, there is little data accounting for, and explaining, the experiences of examination stress. This study aimed to further the understanding of examination stress in secondary school students by conducting interviews with 34…

  19. The Power of Hybridization

    CERN Multimedia

    CERN. Geneva

    2011-01-01

    Programming languages always seem to do some things well but not others: Python punts when it comes to user interfaces, Java’s artificial complexity prevents rapid development and produces tangles, and it will be awhile before we see benefits from C++ concurrency work. The cognitive load of languages and their blind spots increases the cost of experimentation, impeding your ability to fail fast and iterate. If you use a single language to solve your problem, you are binding yourself to the worldview limitations and the mistakes made by the creator of that language. Consider increasing your wiggle room by crossing language boundaries, complementing a language that is powerful in one area with a different language powerful in another. Language hybridization can speed development to quickly discover your real problems, giving you more time to fix them. After making a case for hybridizing your thinking in general, I will present a number of simple examples; first showing the benefits of using other languages...

  20. Parent-Related Stress of Male and Female Carers of Adolescents with Intellectual Disabilities and Carers of Children within the General Population: A Cross-Sectional Comparison

    Science.gov (United States)

    Patton, Kiri A.; Ware, Robert; McPherson, Lyn; Emerson, Eric; Lennox, Nicholas

    2018-01-01

    Background: Carers of children with intellectual disability show high rates of parent-related stress and are at an increased risk for deleterious physical and mental health. Materials and Methods: This study investigated the relationship between demographic and social characteristics and parenting stress, within two different cross-sectional…

  1. Optimal Design for Hybrid Ratio of Carbon/Basalt Hybrid Fiber Reinforced Resin Matrix Composites

    Directory of Open Access Journals (Sweden)

    XU Hong

    2017-08-01

    Full Text Available The optimum hybrid ratio range of carbon/basalt hybrid fiber reinforced resin composites was studied. Hybrid fiber composites with nine different hybrid ratios were prepared before tensile test.According to the structural features of plain weave, the unit cell's performance parameters were calculated. Finite element model was established by using SHELL181 in ANSYS. The simulated values of the sample stiffness in the model were approximately similar to the experimental ones. The stress nephogram shows that there is a critical hybrid ratio which divides the failure mechanism of HFRP into single failure state and multiple failure state. The tensile modulus, strength and limit tensile strain of HFRP with 45% resin are simulated by finite element method. The result shows that the tensile modulus of HFRP with 60% hybrid ratio increases by 93.4% compared with basalt fiber composites (BFRP, and the limit tensile strain increases by 11.3% compared with carbon fiber composites(CFRP.

  2. Stress Management

    Directory of Open Access Journals (Sweden)

    Prof.Univ. Dr. Paul Marinescu

    2007-05-01

    Full Text Available In the post-modern management organizational leaders have the obligation of protecting their employees against factors that could cause damages to their potentially wealthy lives. Stress is such a factor. We shall attempt by means of the present article to draw attention on certain general aspects that should be taken into account in drafting plans for fighting against and diminishing the stress faced by the employees

  3. Hybrid Gear

    Science.gov (United States)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  4. Oxidative stress

    Directory of Open Access Journals (Sweden)

    Osredkar Joško

    2012-05-01

    Full Text Available The human organism is exposed to the influence of various forms of stress, either physical, psychological or chemical, which all have in common that they may adversely affect our body. A certain amount of stress is always present and somehow directs, promotes or inhibits the functioning of the human body. Unfortunately, we are now too many and too often exposed to excessive stress, which certainly has adverse consequences. This is especially true for a particular type of stress, called oxidative stress. All aerobic organisms are exposed to this type of stress because they produce energy by using oxygen. For this type of stress you could say that it is rather imperceptibly involved in our lives, as it becomes apparent only at the outbreak of certain diseases. Today we are well aware of the adverse impact of radicals, whose surplus is the main cause of oxidative stress. However, the key problem remains the detection of oxidative stress, which would allow us to undertake timely action and prevent outbreak of many diseases of our time. There are many factors that promote oxidative stress, among them are certainly a fast lifestyle and environmental pollution. The increase in oxidative stress can also trigger intense physical activity that is directly associated with an increased oxygen consumption and the resulting formation of free radicals. Considering generally positive attitude to physical activity, this fact may seem at first glance contradictory, but the finding has been confimed by several studies in active athletes. Training of a top athlete daily demands great physical effort, which is also reflected in the oxidative state of the organism. However, it should be noted that the top athletes in comparison with normal individuals have a different defense system, which can counteract the negative effects of oxidative stress. Quite the opposite is true for irregular or excessive physical activity to which the body is not adapted.

  5. {pi}{eta} pair hard electroproduction and exotic hybrid mesons

    Energy Technology Data Exchange (ETDEWEB)

    Anikin, I.V. [LPT, Universite Paris-Sud, 91405-Orsay, France, UMR 8627 du CNRS (France); BLTP, JINR, 141980 Dubna (Russian Federation); CPHT, Ecole Polytechnique, 91128 Palaiseau, France, UMR 7644 du CNRS (France); Pire, B. [CPHT, Ecole Polytechnique, 91128 Palaiseau, France, UMR 7644 du CNRS (France); Szymanowski, L. [Soltan Institute for Nuclear Studies, Warsaw (Poland) and Univ. de Liege, B-4000 Liege (Belgium); Teryaev, O.V. [BLTP, JINR, 141980 Dubna (Russian Federation); Wallon, S. [LPT, Universite Paris-Sud, 91405-Orsay, France, UMR 8627 du CNRS (France)

    2005-06-13

    We show that hard electroproduction is a promising way to study exotic hybrid mesons, in particular through the hybrid decay channel H->{pi}{eta}. We discuss the {pi}{eta} generalized distribution amplitude, calculate the production amplitude and propose a forward-backward asymmetry as a signal for the hybrid meson production.

  6. πη pair hard electroproduction and exotic hybrid mesons

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2005-01-01

    We show that hard electroproduction is a promising way to study exotic hybrid mesons, in particular through the hybrid decay channel H->πη. We discuss the πη generalized distribution amplitude, calculate the production amplitude and propose a forward-backward asymmetry as a signal for the hybrid meson production

  7. Hybrid soft computing approaches research and applications

    CERN Document Server

    Dutta, Paramartha; Chakraborty, Susanta

    2016-01-01

    The book provides a platform for dealing with the flaws and failings of the soft computing paradigm through different manifestations. The different chapters highlight the necessity of the hybrid soft computing methodology in general with emphasis on several application perspectives in particular. Typical examples include (a) Study of Economic Load Dispatch by Various Hybrid Optimization Techniques, (b) An Application of Color Magnetic Resonance Brain Image Segmentation by ParaOptiMUSIG activation Function, (c) Hybrid Rough-PSO Approach in Remote Sensing Imagery Analysis,  (d) A Study and Analysis of Hybrid Intelligent Techniques for Breast Cancer Detection using Breast Thermograms, and (e) Hybridization of 2D-3D Images for Human Face Recognition. The elaborate findings of the chapters enhance the exhibition of the hybrid soft computing paradigm in the field of intelligent computing.

  8. Intuitionistic hybrid logic

    DEFF Research Database (Denmark)

    Braüner, Torben

    2011-01-01

    Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area.......Intuitionistic hybrid logic is hybrid modal logic over an intuitionistic logic basis instead of a classical logical basis. In this short paper we introduce intuitionistic hybrid logic and we give a survey of work in the area....

  9. Stress and stressors in the clinical environment: a comparative study of fourth-year student nurses and newly qualified general nurses in Ireland.

    Science.gov (United States)

    Suresh, Patricia; Matthews, Anne; Coyne, Imelda

    2013-03-01

    To measure and compare the perceived levels of job-related stress and stressors of newly qualified nurses and fourth-year student nurses in the clinical environment and to explore the participants' views on stress and stressors. Stress in the nursing workplace has significant consequences for the person, the patient and the organisation, such as psychological and physical health deterioration and impaired professional practice. To address this problem, stress and stressors need to be measured and identified. This study used a cross-sectional survey design and self-reporting questionnaires to measure and compare levels of stress in both groups. Convenience sampling involved all newly qualified nurses (n = 120) and fourth-year student nurses (n = 128) in Dublin North-East region in Ireland. The instrument used was 'The Nursing Stress Scale' (Gray-Toft & Anderson 1981, Journal of Behavioral Assessment 3, 11-23). Descriptive, qualitative analysis was conducted on an open-ended question. Data were obtained from newly qualified nurses (n = 31) and fourth-year student nurses (n = 40) in six acute hospital sites. Levels of perceived stress and stressors were high in both groups. Themes identified from the responses to the open question by both groups included excessive workload, difficult working relationships and unmet clinical learning needs. Student nurses also reported the combination of academic demands with clinical placement as a major stressor. There was no significant difference between each group. Stress continues to be a problem for nurses in the clinical setting. Excessive workload requires urgent attention by hospital managers in view of widespread retention difficulties. Themes identified could provide a framework for possible interventions for improving the clinical environment for nurses. These results can help stakeholders in nurse education and practice to develop interventions to reduce stress for both groups and to ease the transition from student to

  10. Craniomandibular form and body size variation of first generation mouse hybrids: A model for hominin hybridization.

    Science.gov (United States)

    Warren, Kerryn A; Ritzman, Terrence B; Humphreys, Robyn A; Percival, Christopher J; Hallgrímsson, Benedikt; Ackermann, Rebecca Rogers

    2018-03-01

    Hybridization occurs in a number of mammalian lineages, including among primate taxa. Analyses of ancient genomes have shown that hybridization between our lineage and other archaic hominins in Eurasia occurred numerous times in the past. However, we still have limited empirical data on what a hybrid skeleton looks like, or how to spot patterns of hybridization among fossils for which there are no genetic data. Here we use experimental mouse models to supplement previous studies of primates. We characterize size and shape variation in the cranium and mandible of three wild-derived inbred mouse strains and their first generation (F 1 ) hybrids. The three parent taxa in our analysis represent lineages that diverged over approximately the same period as the human/Neanderthal/Denisovan lineages and their hybrids are variably successful in the wild. Comparisons of body size, as quantified by long bone measurements, are also presented to determine whether the identified phenotypic effects of hybridization are localized to the cranium or represent overall body size changes. The results indicate that hybrid cranial and mandibular sizes, as well as limb length, exceed that of the parent taxa in all cases. All three F 1 hybrid crosses display similar patterns of size and form variation. These results are generally consistent with earlier studies on primates and other mammals, suggesting that the effects of hybridization may be similar across very different scenarios of hybridization, including different levels of hybrid fitness. This paper serves to supplement previous studies aimed at identifying F 1 hybrids in the fossil record and to introduce further research that will explore hybrid morphologies using mice as a proxy for better understanding hybridization in the hominin fossil record. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Hybridized Tetraquarks

    CERN Document Server

    Esposito, A.; Polosa, A.D.

    2016-01-01

    We propose a new interpretation of the neutral and charged X, Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules. The latter would require a negative or zero binding energy whose counterpart in h-tetraquarks is a positive quantity. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the Bs pi+- channel by the D0 collaboration and the negative result presented subsequently by the LHCb collaboration are understood in this scheme, together with a considerable portion of available data on X, Z particles. Considerations on a state with the same quantum numbers as the X(5568) are also made.

  12. Stress, coping, and depression: testing new hypotheses in a prospectively studied general population sample of U.S. born Whites and Blacks

    Science.gov (United States)

    Keyes, K.M.; Barnes, D.; Bates, L.M.

    2010-01-01

    The scarcity of empirically supported explanations for the Black/White prevalence difference in depression in the U.S. is a conspicuous gap in the literature. Recent evidence suggests that the paradoxical observation of decreased risk of depression but elevated rates of physical illness among Blacks in the U.S. compared with Whites may be accounted for by the use of coping behaviors (e.g., alcohol and nicotine consumption, overeating) among Blacks exposed to high stress levels. Such coping behaviors may mitigate deleterious effects of stressful exposures on mental health while increasing the risk of physical ailments. The racial patterning in mental and physical health outcomes could therefore be explained by this mechanism if a) these behaviors were more prevalent among Blacks than Whites and/or b) the effect of these behavioral responses to stress was differential by race. The present study challenges this hypothesis using longitudinal, nationally-representative data with comprehensive DSM-IV diagnoses. Data are drawn from 34,653 individuals sampled in Waves 1 (2001-2002) and 2 (2004-2005) as part of the US National Epidemiologic Survey on Alcohol and Related Conditions. Results showed that a) Blacks were less likely to engage in alcohol or nicotine consumption at low, moderate, and high levels of stress compared to Whites, and b) there was a significant three-way interaction between race, stress, and coping behavior for BMI only (F=2.11, df=12, p=0.03), but, contrary to the hypothesis, elevated BMI was protective against depression in Blacks at low, not high, levels of stress. Further, engagement in unhealthy behaviors, especially at pathological levels, did not protect against depression in Blacks or in Whites. In sum, the impact of stress and coping processes on depression do not appear to operate differently in Blacks versus Whites. Further research testing innovative hypotheses that would explain the difference in Black/White depression prevalence is

  13. Stress Analysis of Composites.

    Science.gov (United States)

    1981-01-01

    8217, Finite Elements in Nonlinear Mechanics, 1., 109-130, Tapir Publishers, Norway (1978). 9. A.J. Barnard and P.W. Sharman, ’Elastic-Plastic Analysis Using...Hybrid Stress Finite Elements,’ Finite Elements in Nonlinear Mechanics, 1, 131-148, Tapir Publishers Norway, (1978). ’.........Pian, ’Variational

  14. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Rönnkö, M.; Ravn, Anders Peter; Sere, K.

    2003-01-01

    In this paper we investigate the use of action systems with differential actions in the specifcation of hybrid systems. As the main contribution we generalize the definition of a differential action, allowing the use of arbitrary relations over model variables and their time......-derivatives in modelling continuous-time dynamics. The generalized differential action has an intuitively appealing predicate transformer semantics, which we show to be both conjunctive and monotonic. In addition, we show that differential actions blend smoothly with conventional actions in action systems, even under...... parallel composition. Moreover, as the strength of the action system formalism is the support for stepwise development by refinement, we investigate refinement involving a differential action. We show that, due to the predicate transformer semantics, standard action refinement techniques apply also...

  15. Continuity controlled Hybrid Automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation

  16. Continuity Controlled Hybrid Automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  17. Continuity controlled hybrid automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2004-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  18. Continuity controlled hybrid automata

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2006-01-01

    We investigate the connections between the process algebra for hybrid systems of Bergstra and Middelburg and the formalism of hybrid automata of Henzinger et al. We give interpretations of hybrid automata in the process algebra for hybrid systems and compare them with the standard interpretation of

  19. Hybrid Arrays for Chemical Sensing

    Science.gov (United States)

    Kramer, Kirsten E.; Rose-Pehrsson, Susan L.; Johnson, Kevin J.; Minor, Christian P.

    In recent years, multisensory approaches to environment monitoring for chemical detection as well as other forms of situational awareness have become increasingly popular. A hybrid sensor is a multimodal system that incorporates several sensing elements and thus produces data that are multivariate in nature and may be significantly increased in complexity compared to data provided by single-sensor systems. Though a hybrid sensor is itself an array, hybrid sensors are often organized into more complex sensing systems through an assortment of network topologies. Part of the reason for the shift to hybrid sensors is due to advancements in sensor technology and computational power available for processing larger amounts of data. There is also ample evidence to support the claim that a multivariate analytical approach is generally superior to univariate measurements because it provides additional redundant and complementary information (Hall, D. L.; Linas, J., Eds., Handbook of Multisensor Data Fusion, CRC, Boca Raton, FL, 2001). However, the benefits of a multisensory approach are not automatically achieved. Interpretation of data from hybrid arrays of sensors requires the analyst to develop an application-specific methodology to optimally fuse the disparate sources of data generated by the hybrid array into useful information characterizing the sample or environment being observed. Consequently, multivariate data analysis techniques such as those employed in the field of chemometrics have become more important in analyzing sensor array data. Depending on the nature of the acquired data, a number of chemometric algorithms may prove useful in the analysis and interpretation of data from hybrid sensor arrays. It is important to note, however, that the challenges posed by the analysis of hybrid sensor array data are not unique to the field of chemical sensing. Applications in electrical and process engineering, remote sensing, medicine, and of course, artificial

  20. Model Reduction of Hybrid Systems

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza

    gramians. Generalized gramians are the solutions to the observability and controllability Lyapunov inequalities. In the first framework the projection matrices are found based on the common generalized gramians. This framework preserves the stability of the original switched system for all switching...... is guaranteed to be preserved for arbitrary switching signal. To compute the common generalized gramians linear matrix inequalities (LMI’s) need to be solved. These LMI’s are not always feasible. In order to solve the problem of conservatism, the second framework is presented. In this method the projection......High-Technological solutions of today are characterized by complex dynamical models. A lot of these models have inherent hybrid/switching structure. Hybrid/switched systems are powerful models for distributed embedded systems design where discrete controls are applied to continuous processes...

  1. Genomic Prediction of Barley Hybrid Performance

    Directory of Open Access Journals (Sweden)

    Norman Philipp

    2016-07-01

    Full Text Available Hybrid breeding in barley ( L. offers great opportunities to accelerate the rate of genetic improvement and to boost yield stability. A crucial requirement consists of the efficient selection of superior hybrid combinations. We used comprehensive phenotypic and genomic data from a commercial breeding program with the goal of examining the potential to predict the hybrid performances. The phenotypic data were comprised of replicated grain yield trials for 385 two-way and 408 three-way hybrids evaluated in up to 47 environments. The parental lines were genotyped using a 3k single nucleotide polymorphism (SNP array based on an Illumina Infinium assay. We implemented ridge regression best linear unbiased prediction modeling for additive and dominance effects and evaluated the prediction ability using five-fold cross validations. The prediction ability of hybrid performances based on general combining ability (GCA effects was moderate, amounting to 0.56 and 0.48 for two- and three-way hybrids, respectively. The potential of GCA-based hybrid prediction requires that both parental components have been evaluated in a hybrid background. This is not necessary for genomic prediction for which we also observed moderate cross-validated prediction abilities of 0.51 and 0.58 for two- and three-way hybrids, respectively. This exemplifies the potential of genomic prediction in hybrid barley. Interestingly, prediction ability using the two-way hybrids as training population and the three-way hybrids as test population or vice versa was low, presumably, because of the different genetic makeup of the parental source populations. Consequently, further research is needed to optimize genomic prediction approaches combining different source populations in barley.

  2. Corporate Hybrid Bonds

    OpenAIRE

    Ahlberg, Johan; Jansson, Anton

    2016-01-01

    Hybrid securities do not constitute a new phenomenon in the Swedish capital markets. Most commonly, hybrids issued by Swedish real estate companies in recent years are preference shares. Corporate hybrid bonds on the other hand may be considered as somewhat of a new-born child in the family of hybrid instruments. These do, as all other hybrid securities, share some equity-like and some debt-like characteristics. Nevertheless, since 2013 the interest for the instrument has grown rapidly and ha...

  3. Hybrid XRF

    International Nuclear Information System (INIS)

    Heckel, J.

    2002-01-01

    Full text: In the last 10 years significant innovations of EDXRF, e.g. total reflection XRF or polarized beam XRF, were utilized in different industrial applications. The decrease of background within the spectra was the goal of these developments. Excellent detection limits and sensitivities demonstrate the success of these new techniques. Nevertheless, further improvements are possible by using Si drift detectors. These detectors allow the processing of input count rates up to 10 6 cps in comparison to 10 5 of Si(Li) detectors. New excitation optics are necessary to produce such count rates. One possibility is the use of doubly curved crystals between tube and sample. These crystals enable the reflection of the primary beam within the given solid angle (0.4π) of an end window tube to the sample. Using such brightness optics excellent sensitivities mainly for light elements are achievable. The combination of a BRAGG crystal as a wavelength dispersive component and a solid state detector as an energy dispersive component creates a new technique: hybrid XRF. Copyright (2002) Australian X-ray Analytical Association Inc. Copyright (2002) Australian X-ray Analytical Association Inc

  4. Forces in General Relativity

    Science.gov (United States)

    Ridgely, Charles T.

    2010-01-01

    Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…

  5. Concurrent and prospective associations of habitual overgeneral memory and prospection with symptoms of depression, general anxiety, obsessive compulsiveness, and post-traumatic stress

    NARCIS (Netherlands)

    Boelen, Paul A.; Huntjens, Rafaele J. C.; van den Hout, Marcel A.

    2014-01-01

    Reduced memory specificity is associated with depression, post-traumatic stress disorder (PTSD), and some other forms of psychopathology. Reduced memory specificity is also associated with reduced specificity of envisioned future events. Research in this area has mostly relied on cue-word methods

  6. The Mediating Effects of Work-Related Stress on Mentoring Functions and Job Attitude: A Comparison of General and Special Education Teachers

    Science.gov (United States)

    Rabenhorst, Greg A.

    2011-01-01

    The current study is designed to investigate the mediating effects of work-related stress on the relationship between mentoring functions (i.e., career support, psychosocial support, and role modeling) and measures of job attitude (i.e., job satisfaction and organizational commitment). Mentoring is widely used as a means of assisting in the new…

  7. Hybrid mimics and hybrid vigor in Arabidopsis

    Science.gov (United States)

    Wang, Li; Greaves, Ian K.; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S.; Peacock, W. James

    2015-01-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture. PMID:26283378

  8. Stress, coping, and depression: testing a new hypothesis in a prospectively studied general population sample of U.S.-born Whites and Blacks.

    Science.gov (United States)

    Keyes, K M; Barnes, David M; Bates, L M

    2011-03-01

    The scarcity of empirically supported explanations for the Black/White prevalence difference in depression in the U.S. is a conspicuous gap in the literature. Recent evidence suggests that the paradoxical observation of decreased risk of depression but elevated rates of physical illness among Blacks in the U.S. compared with Whites may be accounted for by the use of coping behaviors (e.g., alcohol and nicotine consumption, overeating) among Blacks exposed to high stress levels. Such coping behaviors may mitigate deleterious effects of stressful exposures on mental health while increasing the risk of physical ailments. The racial patterning in mental and physical health outcomes could therefore be explained by this mechanism if a) these behaviors were more prevalent among Blacks than Whites and/or b) the effect of these behavioral responses to stress was differential by race. The present study challenges this hypothesis using longitudinal, nationally-representative data with comprehensive DSM-IV diagnoses. Data are drawn from 34,653 individuals sampled in Waves 1 (2001-2002) and 2 (2004-2005) as part of the US National Epidemiologic Survey on Alcohol and Related Conditions. Results showed that a) Blacks were less likely to engage in alcohol or nicotine consumption at low, moderate, and high levels of stress compared to Whites, and b) there was a significant three-way interaction between race, stress, and coping behavior for BMI only (F = 2.11, df = 12, p = 0.03), but, contrary to the hypothesis, elevated BMI was protective against depression in Blacks at low, not high, levels of stress. Further, engagement in unhealthy behaviors, especially at pathological levels, did not protect against depression in Blacks or in Whites. In sum, the impact of stress and coping processes on depression does not appear to operate differently in Blacks versus Whites. Further research testing innovative hypotheses that would explain the difference in Black/White depression prevalence is

  9. Elastic-plastic and creep analyses by assumed stress finite elements

    International Nuclear Information System (INIS)

    Pian, T.H.H.; Spilker, R.L.; Lee, S.W.

    1975-01-01

    A formulation is presented of incremental finite element solutions for both initial stress and initial strain problems based on modified complementary energy principle with relaxed inter-element continuity requirement. The corresponding finite element model is the assumed stress hybrid model which has stress parameters in the interior of each element and displacements at the individual nodes as unknowns. The formulation includes an important consideration that the states of stress and strain and the beginning of each increment may not satisfy the equilibrium and compatibility equations. These imbalance and mismatch conditions all lead to correction terms for the equivalent nodal forces of the matrix equations. The initial stress method is applied to elastic-plastic analysis of structures. In this case the stress parameters for the individual elements can be eliminated resulting to a system of equations with only nodal displacements as unknowns. Two different complementary energy principles can be formulated, in one of which the equilibrium of the final state of stress is maintained while in the other the equilibrium of the stress increments is maintained. Each of these two different formulations can be combined with different iterative schemes to be used at each incremental steps of the elastic-plastic analysis. It is also indicated clearly that for the initial stress method the state of stress at the beginning of each increments is in general, not in equilibrium and an imbalance correction is needed. Results of a comprehensive evaluation of various solution procedures by the initial stress method using the assumed stress hybrid elements are presented. The example used is the static response of a thick wall cylinder of elastic-perfectly plastic material under internal pressure. Solid of revolution elements with rectangular cross sections are used

  10. Interaction of the heterotrimeric G protein alpha subunit SSG-1 of Sporothrix schenckii with proteins related to stress response and fungal pathogenicity using a yeast two-hybrid assay

    Directory of Open Access Journals (Sweden)

    González-Méndez Ricardo

    2010-12-01

    Full Text Available Abstract Background Important biological processes require selective and orderly protein-protein interactions at every level of the signalling cascades. G proteins are a family of heterotrimeric GTPases that effect eukaryotic signal transduction through the coupling of cell surface receptors to cytoplasmic effector proteins. They have been associated with growth and pathogenicity in many fungi through gene knock-out studies. In Sporothrix schenckii, a pathogenic, dimorphic fungus, we previously identified a pertussis sensitive G alpha subunit, SSG-1. In this work we inquire into its interactions with other proteins. Results Using the yeast two-hybrid technique, we identified protein-protein interactions between SSG-1 and other important cellular proteins. The interactions were corroborated using co-immuneprecipitation. Using these techniques we identified a Fe/Mn superoxide dismutase (SOD, a glyceraldehyde-3-P dehydrogenase (GAPDH and two ion transport proteins, a siderophore-iron transporter belonging to the Major Facilitator Superfamily (MFS and a divalent-cation transporter of the Nramp (natural resistance-associated macrophage protein family as interacting with SSG-1. The cDNA's encoding these proteins were sequenced and bioinformatic macromolecular sequence analyses were used for the correct classification and functional assignment. Conclusions This study constitutes the first report of the interaction of a fungal G alpha inhibitory subunit with SOD, GAPDH, and two metal ion transporters. The identification of such important proteins as partners of a G alpha subunit in this fungus suggests possible mechanisms through which this G protein can affect pathogenicity and survival under conditions of environmental stress or inside the human host. The two ion transporters identified in this work are the first to be reported in S. schenckii and the first time they are identified as interacting with fungal G protein alpha subunits. The association

  11. Novel brewing yeast hybrids: creation and application.

    Science.gov (United States)

    Krogerus, Kristoffer; Magalhães, Frederico; Vidgren, Virve; Gibson, Brian

    2017-01-01

    The natural interspecies Saccharomyces cerevisiae × Saccharomyces eubayanus hybrid yeast is responsible for global lager beer production and is one of the most important industrial microorganisms. Its success in the lager brewing environment is due to a combination of traits not commonly found in pure yeast species, principally low-temperature tolerance, and maltotriose utilization. Parental transgression is typical of hybrid organisms and has been exploited previously for, e.g., the production of wine yeast with beneficial properties. The parental strain S. eubayanus has only been discovered recently and newly created lager yeast strains have not yet been applied industrially. A number of reports attest to the feasibility of this approach and artificially created hybrids are likely to have a significant impact on the future of lager brewing. De novo S. cerevisiae × S. eubayanus hybrids outperform their parent strains in a number of respects, including, but not restricted to, fermentation rate, sugar utilization, stress tolerance, and aroma formation. Hybrid genome function and stability, as well as different techniques for generating hybrids and their relative merits are discussed. Hybridization not only offers the possibility of generating novel non-GM brewing yeast strains with unique properties, but is expected to aid in unraveling the complex evolutionary history of industrial lager yeast.

  12. Range and specificity of war-related trauma to posttraumatic stress; depression and general health perception: displaced former World War II children in late life.

    Science.gov (United States)

    Strauss, Kristin; Dapp, Ulrike; Anders, Jennifer; von Renteln-Kruse, Wolfgang; Schmidt, Silke

    2011-02-01

    Dose-response relation of war experiences and posttraumatic stress, depression and poor health functioning in late life is well documented in war-affected populations. The influence of differing trauma types experienced by war-affected population in the study of dose-response relation of war trauma and psychological maladaptation in late life has not been investigated. We examined a subgroup of displaced elders and investigated whether specific trauma types were associated with differential health outcomes. From representative practitioner lists, matched groups of former displaced and non-displaced World War II children were assigned, yielding a total sample of 417 participants (response rate 50%). Measurement encompassed a self-report survey including the Impact of Event Scale-Revised, the Patient Health Questionnaire and the Harvard Trauma Questionnaire. Consistent dose-relation between war-related experiences and posttraumatic stress or depressive symptoms in late life was found for both, displaced and non-displaced elders, whereas a gradient for poor health perception was only found in displaced people. Trauma types derived from principal component analysis showed differential associations with health outcomes. Human Right Violations emerged as risk factor for posttraumatic stress symptoms and Deprivation & Threat to Life as risk factor for depressive symptoms. Poor self-rated health was associated with multiple trauma types. Non-random recruitment, retrospective design and use of self-report. Posttraumatic stress and depression are associated with war-related experiences more than 60 years after World War II. Results suggest that different trauma types lead to unique variants of syndrome configurations, which may result from different etiological factors. © 2010 Elsevier B.V. All rights reserved.

  13. Generalized Superconductivity. Generalized Levitation

    International Nuclear Information System (INIS)

    Ciobanu, B.; Agop, M.

    2004-01-01

    In the recent papers, the gravitational superconductivity is described. We introduce the concept of generalized superconductivity observing that any nongeodesic motion and, in particular, the motion in an electromagnetic field, can be transformed in a geodesic motion by a suitable choice of the connection. In the present paper, the gravitoelectromagnetic London equations have been obtained from the generalized Helmholtz vortex theorem using the generalized local equivalence principle. In this context, the gravitoelectromagnetic Meissner effect and, implicitly, the gravitoelectromagnetic levitation are given. (authors)

  14. Hybrid reactors: Nuclear breeding or energy production?

    International Nuclear Information System (INIS)

    Piera, Mireia; Lafuente, Antonio; Abanades, Alberto; Martinez-Val, J.M.

    2010-01-01

    After reviewing the long-standing tradition on hybrid research, an assessment model is presented in order to characterize the hybrid performance under different objectives. In hybrids, neutron multiplication in the subcritical blanket plays a major role, not only for energy production and nuclear breeding, but also for tritium breeding, which is fundamental requirement in fusion-fission hybrids. All three objectives are better achieved with high values of the neutron multiplication factor (k-eff) with the obvious and fundamental limitation that it cannot reach criticality under any event, particularly, in the case of a loss of coolant accident. This limitation will be very important in the selection of the coolant. Some general considerations will be proposed, as guidelines for assessing the hybrid potential in a given scenario. Those guidelines point out that hybrids can be of great interest for the future of nuclear energy in a framework of Sustainable Development, because they can contribute to the efficient exploitation of nuclear fuels, with very high safety features. Additionally, a proposal is presented on a blanket specially suited for fusion-fission hybrids, although this reactor concept is still under review, and new work is needed for identifying the most suitable blanket composition, which can vary depending on the main objective of the hybrid.

  15. The influence of maternal vulnerability and parenting stress on chronic pain in adolescents in a general population sample: the TRAILS study

    NARCIS (Netherlands)

    Passchier, J.; Darlington, A.S.; Verhulst, F.C.; De Winter, A.F.; Ormel, J.; Hunfeld, J.A.

    2012-01-01

    Investigating possible psychosocial predictors of unexplained chronic pain in adolescents is crucial in understanding its development and prevention. A general population sample of adolescents (n = 2230) from the TRAILS cohort study was investigated longitudinally to assess the influence of maternal

  16. The influence of maternal vulnerability and parenting stress on chronic pain in adolescents in a general population sample : The TRAILS study

    NARCIS (Netherlands)

    Darlington, A-S. E.; Verhulst, F. C.; De Winter, A. F.; Ormel, J.; Passchier, J.; Hunfeld, J. A. M.

    Investigating possible psychosocial predictors of unexplained chronic pain in adolescents is crucial in understanding its development and prevention. A general population sample of adolescents (n = 2230) from the TRAILS cohort study was investigated longitudinally to assess the influence of maternal

  17. Chemical sensors are hybrid-input memristors

    Science.gov (United States)

    Sysoev, V. I.; Arkhipov, V. E.; Okotrub, A. V.; Pershin, Y. V.

    2018-04-01

    Memristors are two-terminal electronic devices whose resistance depends on the history of input signal (voltage or current). Here we demonstrate that the chemical gas sensors can be considered as memristors with a generalized (hybrid) input, namely, with the input consisting of the voltage, analyte concentrations and applied temperature. The concept of hybrid-input memristors is demonstrated experimentally using a single-walled carbon nanotubes chemical sensor. It is shown that with respect to the hybrid input, the sensor exhibits some features common with memristors such as the hysteretic input-output characteristics. This different perspective on chemical gas sensors may open new possibilities for smart sensor applications.

  18. The theory of hybrid stochastic algorithms

    International Nuclear Information System (INIS)

    Duane, S.; Kogut, J.B.

    1986-01-01

    The theory of hybrid stochastic algorithms is developed. A generalized Fokker-Planck equation is derived and is used to prove that the correct equilibrium distribution is generated by the algorithm. Systematic errors following from the discrete time-step used in the numerical implementation of the scheme are computed. Hybrid algorithms which simulate lattice gauge theory with dynamical fermions are presented. They are optimized in computer simulations and their systematic errors and efficiencies are studied. (orig.)

  19. Hybrid Management in Hospitals

    DEFF Research Database (Denmark)

    Byrkjeflot, Haldor; Jespersen, Peter Kragh

    2010-01-01

    Artiklen indeholder et litteraturbaseret studium af ledelsesformer i sygehuse, hvor sundhedsfaglig ledelse og generel ledelse mikses til hybride ledelsesformer......Artiklen indeholder et litteraturbaseret studium af ledelsesformer i sygehuse, hvor sundhedsfaglig ledelse og generel ledelse mikses til hybride ledelsesformer...

  20. Hydraulic Hybrid Vehicles

    Science.gov (United States)

    EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

  1. Functional stability of endothelial cells on a novel hybrid scaffold for vascular tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Pankajakshan, Divya; Krishnan, Lissy K [Thrombosis Research Unit, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Trivandrum 695 012 (India); Krishnan V, Kalliyana, E-mail: lissykk@sctimst.ac.i [Division of Polymer Technology, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Trivandrum 695 012 (India)

    2010-12-15

    Porous and pliable conduits made of biodegradable polymeric scaffolds offer great potential for the development of blood vessel substitutes but they generally lack signals for cell proliferation, survival and maintenance of a normal phenotype. In this study we have prepared and evaluated porous poly({epsilon}-caprolactone) (PCL) integrated with fibrin composite (FC) to get a biomimetic hybrid scaffold (FC PCL) with the biological properties of fibrin, fibronectin (FN), gelatin, growth factors and glycosaminoglycans. Reduced platelet adhesion on a human umbilical vein endothelial cell-seeded hybrid scaffold as compared to bare PCL or FC PCL was observed, which suggests the non-thrombogenic nature of the tissue-engineered scaffold. Analysis of real-time polymerase chain reaction (RT-PCR) after 5 days of endothelial cell (EC) culture on a hybrid scaffold indicated that the prothrombotic von Willebrand factor and plasminogen activator inhibitor (PAI) were quiescent and stable. Meanwhile, dynamic expressions of tissue plasminogen activator (tPA) and endothelial nitric oxide synthase indicated the desired cell phenotype on the scaffold. On the hybrid scaffold, shear stress could induce enhanced nitric oxide release, which implicates vaso-responsiveness of EC grown on the tissue-engineered construct. Significant upregulation of mRNA for extracellular matrix (ECM) proteins, collagen IV and elastin, in EC was detected by RT-PCR after growing them on the hybrid scaffold and FC-coated tissue culture polystyrene (FC TCPS) but not on FN-coated TCPS. The results indicate that the FC PCL hybrid scaffold can accomplish a remodeled ECM and non-thrombogenic EC phenotype, and can be further investigated as a scaffold for cardiovascular tissue engineering. (communication)

  2. Functional stability of endothelial cells on a novel hybrid scaffold for vascular tissue engineering

    International Nuclear Information System (INIS)

    Pankajakshan, Divya; Krishnan, Lissy K; Krishnan V, Kalliyana

    2010-01-01

    Porous and pliable conduits made of biodegradable polymeric scaffolds offer great potential for the development of blood vessel substitutes but they generally lack signals for cell proliferation, survival and maintenance of a normal phenotype. In this study we have prepared and evaluated porous poly(ε-caprolactone) (PCL) integrated with fibrin composite (FC) to get a biomimetic hybrid scaffold (FC PCL) with the biological properties of fibrin, fibronectin (FN), gelatin, growth factors and glycosaminoglycans. Reduced platelet adhesion on a human umbilical vein endothelial cell-seeded hybrid scaffold as compared to bare PCL or FC PCL was observed, which suggests the non-thrombogenic nature of the tissue-engineered scaffold. Analysis of real-time polymerase chain reaction (RT-PCR) after 5 days of endothelial cell (EC) culture on a hybrid scaffold indicated that the prothrombotic von Willebrand factor and plasminogen activator inhibitor (PAI) were quiescent and stable. Meanwhile, dynamic expressions of tissue plasminogen activator (tPA) and endothelial nitric oxide synthase indicated the desired cell phenotype on the scaffold. On the hybrid scaffold, shear stress could induce enhanced nitric oxide release, which implicates vaso-responsiveness of EC grown on the tissue-engineered construct. Significant upregulation of mRNA for extracellular matrix (ECM) proteins, collagen IV and elastin, in EC was detected by RT-PCR after growing them on the hybrid scaffold and FC-coated tissue culture polystyrene (FC TCPS) but not on FN-coated TCPS. The results indicate that the FC PCL hybrid scaffold can accomplish a remodeled ECM and non-thrombogenic EC phenotype, and can be further investigated as a scaffold for cardiovascular tissue engineering. (communication)

  3. Mesoscale hybrid calibration artifact

    Science.gov (United States)

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  4. Hybrid quantum information processing

    Energy Technology Data Exchange (ETDEWEB)

    Furusawa, Akira [Department of Applied Physics, School of Engineering, The University of Tokyo (Japan)

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  5. Euro hybrid materials and structures. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Hausmann, Joachim M.; Siebert, Marc (eds.)

    2016-08-01

    In order to use the materials as best as possible, several different materials are usually mixed in one component, especially in the field of lightweight design. If these combinations of materials are joined inherently, they are called multi material design products or hybrid structures. These place special requirements on joining technology, design methods and manufacturing and are challenging in other aspects, too. The eight chapters with manuscripts of the presentations are: Chapter 1- Interface: What happens in the interface between the two materials? Chapter 2 - Corrosion and Residual Stresses: How about galvanic corrosion and thermal residual stresses in the contact zone of different materials? Chapter 3 - Characterization: How to characterize and test hybrid materials? Chapter 4 - Design: What is a suitable design and dimensioning method for hybrid structures? Chapter 5 - Machining and Processing: How to machine and process hybrid structures and materials? Chapter 6 - Component Manufacturing: What is a suitable manufacturing route for hybrid structures? Chapter 7 - Non-Destructive Testing and Quality Assurance: How to assure the quality of material and structures? Chapter 8 - Joining: How to join components of different materials?.

  6. Euro hybrid materials and structures. Proceedings

    International Nuclear Information System (INIS)

    Hausmann, Joachim M.; Siebert, Marc

    2016-01-01

    In order to use the materials as best as possible, several different materials are usually mixed in one component, especially in the field of lightweight design. If these combinations of materials are joined inherently, they are called multi material design products or hybrid structures. These place special requirements on joining technology, design methods and manufacturing and are challenging in other aspects, too. The eight chapters with manuscripts of the presentations are: Chapter 1- Interface: What happens in the interface between the two materials? Chapter 2 - Corrosion and Residual Stresses: How about galvanic corrosion and thermal residual stresses in the contact zone of different materials? Chapter 3 - Characterization: How to characterize and test hybrid materials? Chapter 4 - Design: What is a suitable design and dimensioning method for hybrid structures? Chapter 5 - Machining and Processing: How to machine and process hybrid structures and materials? Chapter 6 - Component Manufacturing: What is a suitable manufacturing route for hybrid structures? Chapter 7 - Non-Destructive Testing and Quality Assurance: How to assure the quality of material and structures? Chapter 8 - Joining: How to join components of different materials?

  7. General general game AI

    OpenAIRE

    Togelius, Julian; Yannakakis, Georgios N.; 2016 IEEE Conference on Computational Intelligence and Games (CIG)

    2016-01-01

    Arguably the grand goal of artificial intelligence research is to produce machines with general intelligence: the capacity to solve multiple problems, not just one. Artificial intelligence (AI) has investigated the general intelligence capacity of machines within the domain of games more than any other domain given the ideal properties of games for that purpose: controlled yet interesting and computationally hard problems. This line of research, however, has so far focuse...

  8. Transgressive Hybrids as Hopeful Monsters.

    Science.gov (United States)

    Dittrich-Reed, Dylan R; Fitzpatrick, Benjamin M

    2013-06-01

    The origin of novelty is a critical subject for evolutionary biologists. Early geneticists speculated about the sudden appearance of new species via special macromutations, epitomized by Goldschmidt's infamous "hopeful monster". Although these ideas were easily dismissed by the insights of the Modern Synthesis, a lingering fascination with the possibility of sudden, dramatic change has persisted. Recent work on hybridization and gene exchange suggests an underappreciated mechanism for the sudden appearance of evolutionary novelty that is entirely consistent with the principles of modern population genetics. Genetic recombination in hybrids can produce transgressive phenotypes, "monstrous" phenotypes beyond the range of parental populations. Transgressive phenotypes can be products of epistatic interactions or additive effects of multiple recombined loci. We compare several epistatic and additive models of transgressive segregation in hybrids and find that they are special cases of a general, classic quantitative genetic model. The Dobzhansky-Muller model predicts "hopeless" monsters, sterile and inviable transgressive phenotypes. The Bateson model predicts "hopeful" monsters with fitness greater than either parental population. The complementation model predicts both. Transgressive segregation after hybridization can rapidly produce novel phenotypes by recombining multiple loci simultaneously. Admixed populations will also produce many similar recombinant phenotypes at the same time, increasing the probability that recombinant "hopeful monsters" will establish true-breeding evolutionary lineages. Recombination is not the only (or even most common) process generating evolutionary novelty, but might be the most credible mechanism for sudden appearance of new forms.

  9. Stress Management: Job Stress

    Science.gov (United States)

    Healthy Lifestyle Stress management Job stress can be all-consuming — but it doesn't have to be. Address your triggers, keep perspective and ... stress triggers, it's often helpful to improve time management skills — especially if you tend to feel overwhelmed ...

  10. Exposure to high hydrostatic pressure rapidly selects for increased RpoS activity and general stress-resistance in Escherichia coli O157:H7.

    Science.gov (United States)

    Vanlint, Dietrich; Rutten, Nele; Govers, Sander K; Michiels, Chris W; Aertsen, Abram

    2013-04-15

    Exposure to high hydrostatic pressure (HHP) is increasingly being used in food preservation as a non-thermal pasteurization process, and its further implementation necessitates a more thorough understanding of bacterial resistance development and intraspecies variability with regard to inactivation by HHP. In this report, we discovered that exposure to high hydrostatic pressure stress can rapidly select for strongly increased RpoS activity in a hypersensitive Escherichia coli O157:H7 strain (ATCC 43888), leading to a simultaneous increase in HHP and heat resistance. Moreover, the level of RpoS activity correlated well with the original hypersensitivity and the extent of acquired HHP resistance, and extremely HHP-resistant mutants of ATCC 43888 clearly incurred a number of additional RpoS-dependent phenotypes. These findings suggest that implementation of novel processing techniques in the food production chain can readily affect the physiology of food-borne pathogens. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. The effect of oblique angle of sound incidence, realistic edge conditions, curvature and in-plane panel stresses on the noise reduction characteristics of general aviation type panels

    Science.gov (United States)

    Grosveld, F.; Lameris, J.; Dunn, D.

    1979-01-01

    Experiments and a theoretical analysis were conducted to predict the noise reduction of inclined and curved panels. These predictions are compared to the experimental results with reasonable agreement between theory and experiment for panels under an oblique angle of sound incidence. Theoretical as well as experimental results indicate a big increase in noise reduction when a flat test panel is curved. Further curving the panel slightly decreases the noise reduction. Riveted flat panels are shown to give a higher noise reduction in the stiffness-controlled frequency region, while bonded panels are superior in this region when the test panel is curved. Experimentally measured noise reduction characteristics of flat aluminum panels with uniaxial in-plane stresses are presented and discussed. These test results indicate an important improvement in the noise reduction of these panels in the frequency range below the fundamental panel/cavity frequency.

  12. Hybrid rail gun electromagnetic accelerators

    International Nuclear Information System (INIS)

    Chen, K.W.; Hachen, H.; Lee, A.; Legh, G.; Lin, T.; Mattay, S.; Wipf, S.

    1983-01-01

    Theoretical and experimental investigations on hybrid rail accelerators are presented. It is shown that the side surface areas and in some cases sabots of the projectile can be used to provide substantial amount of additional thrust. Moreover, it is shown that in most cases examined, external magnetic fields can be conveniently incorporated in the accelerator designs to supplement the rail-induced fields. Total thrusts in excess of 10 MN for kilogram-sized projectiles can in principle be established with driving currents of the order of 1 MA. No obvious stress limitations are foreseen. The percentages of thrust from external magnetic fields are sufficiently high that the use of which should be encouraged. The increased flexibility in the projectile shapes available permits the use of the proposed hybrid electromagnetic launcher technology in a variety of new areas, such as thrust boosts in conventional chemical rockets and other similar applications. Furthermore, the additional thrust obtained from the use of side surface areas greatly increases the maximum permissable thrust otherwise limited by material strength considerations. Thrust analyses for projectiles in several hybrid rail accelerator designs are discussed. Some laboratory experimental observations are presented

  13. Hybrid Integrated Platforms for Silicon Photonics

    Science.gov (United States)

    Liang, Di; Roelkens, Gunther; Baets, Roel; Bowers, John E.

    2010-01-01

    A review of recent progress in hybrid integrated platforms for silicon photonics is presented. Integration of III-V semiconductors onto silicon-on-insulator substrates based on two different bonding techniques is compared, one comprising only inorganic materials, the other technique using an organic bonding agent. Issues such as bonding process and mechanism, bonding strength, uniformity, wafer surface requirement, and stress distribution are studied in detail. The application in silicon photonics to realize high-performance active and passive photonic devices on low-cost silicon wafers is discussed. Hybrid integration is believed to be a promising technology in a variety of applications of silicon photonics.

  14. Hybrid Integrated Platforms for Silicon Photonics

    Directory of Open Access Journals (Sweden)

    John E. Bowers

    2010-03-01

    Full Text Available A review of recent progress in hybrid integrated platforms for silicon photonics is presented. Integration of III-V semiconductors onto silicon-on-insulator substrates based on two different bonding techniques is compared, one comprising only inorganic materials, the other technique using an organic bonding agent. Issues such as bonding process and mechanism, bonding strength, uniformity, wafer surface requirement, and stress distribution are studied in detail. The application in silicon photonics to realize high-performance active and passive photonic devices on low-cost silicon wafers is discussed. Hybrid integration is believed to be a promising technology in a variety of applications of silicon photonics.

  15. [Psychosomatic basic care in the general hospital - an empirical investigation of the bio-psycho-social stress, treatment procedures and treatment outcomes from the vantage point of medical doctors].

    Science.gov (United States)

    Fritzsche, Kurt; Schäfer, Inna; Wirsching, Michael; Leonhart, Rainer

    2012-01-01

    The present study investigates the psycho-social stress, the treatment procedures and the treatment outcomes of stressed patients in the hospital from the perspective of the hospital doctors. Physicians from all disciplines who had completed the course "Psychosomatic Basic Care" as part of their specialist training documented selected treatment cases. 2,028 documented treatment cases of 367 physicians were evaluated. Anxiety, depression and family problems were the most common causes of psychosocial stress. In over 40 % of the cases no information was found on the medical history. Diagnostic and therapeutic conversations took place with almost half the patients (45%). From the vantage point of the physicians patients receiving diagnostic and therapeutic conversations achieved significantly more positive scores with respect to outcome variables than patients without these measures. Collegial counseling was desired for more than half of the patients and took place mainly among the ward team. There were few significant differences in the views of surgical and nonsurgical physicians. Psychosomatic basic care in general hospitals is possible, albeit with some limitations. Patients undergoing psychosocial interventions have better treatment outcomes. Therefore, extending training to 80 hours for all medical disciplines seems reasonable.

  16. Childhood Stress

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Childhood Stress KidsHealth / For Parents / Childhood Stress What's in this ... and feel stress to some degree. Sources of Stress Stress is a function of the demands placed ...

  17. Generalized fiber Fourier optics.

    Science.gov (United States)

    Cincotti, Gabriella

    2011-06-15

    A twofold generalization of the optical schemes that perform the discrete Fourier transform (DFT) is given: new passive planar architectures are presented where the 2 × 2 3 dB couplers are replaced by M × M hybrids, reducing the number of required connections and phase shifters. Furthermore, the planar implementation of the discrete fractional Fourier transform (DFrFT) is also described, with a waveguide grating router (WGR) configuration and a properly modified slab coupler.

  18. Psychosocial work factors and burnout : a study of a working general population and patients at a stress rehabilitation clinic

    OpenAIRE

    Norlund, Sofia

    2011-01-01

    Background The psychosocial work environment affects our health (e.g., sick leave and mortality rates). Research on psychosocial work factors and burnout has focused on specific workplaces or occupations and rarely evaluated in the general population or used longitudinal designs. In Sweden, the diagnosis of exhaustion disorder (closely related to burnout) is a common cause for sick leave. The effects of psychosocial work environments on the process of returning to work has not been studied in...

  19. [Stress in surgeries].

    Science.gov (United States)

    Daian, Márcia Rodrigues; Petroianu, Andy; Alberti, Luiz Ronaldo; Jeunon, Ester Eliane

    2012-01-01

    The purpose of this article was to provide the literature regarding the psychological stress in the peri-operative period of adult patients undergoing operations under general anesthesia. The articles were obtained by surveying the papers published and catalogued in the Medline Pubmed interface database, Lilacs and the Biblioteca Virtual de Saúde (BVS) since 1984, crossing the headings stress, surgery, general anesthesia, psychology. Over 800 articles related to stress and surgery were analyzed with regards to their relevance to the considered subject. Eighteen articles were related to psychological stress. Their results confirmed the presence of psychological and physical stress, during the peri-operative period as well as relation between stress and de clinical post-operative recovery. There is a gap regarding in the peri-operative period. More studies on psychological influence on stress may benefit patients and help professionals during the surgical treatment.

  20. Major benzophenone concentrations and influence of food consumption among the general population in Korea, and the association with oxidative stress biomarker.

    Science.gov (United States)

    Kim, Bokyung; Kwon, Bareum; Jang, Sol; Kim, Pan-Gyi; Ji, Kyunghee

    2016-09-15

    Benzophenones (BPs) have been used as sunscreen agents and as ultraviolet stabilizers in plastic surface coatings for food packaging. However, few studies have been performed to examine the level of human exposure to BPs and the potential sources of such exposure. We evaluated the exposure levels to six major BPs (BP-1, BP-2, BP-3, BP-4, BP-8, and 4-hydroxybenzophenone (4-OH-BP)) among the adult population in two cities in Korea, and investigated the potential dietary sources of the BPs. Urinary levels of malondialdehyde (MDA) as an oxidative stress biomarker as well as their association with the levels of BPs were also analyzed. Among the six BPs analyzed, 4-OH-BP, BP-1, BP-3, and BP-4 were detected in 77%, 49%, 27%, and 21% of the population, respectively. BP concentrations were relatively higher in younger (people in their 20s and 30s) cosmetic users and leaner women. Even after the adjustment of age, body mass index, and cosmetic use, the consumption of frozen storage food, instant noodles, and instant coffee was significantly correlated with urinary BPs, and these associations were sex-dependent. No significant correlation was observed between the levels of BPs and levels of MDA. The results of the present study will be useful for developing plans of public health management of BPs. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Concurrent and prospective associations of habitual overgeneral memory and prospection with symptoms of depression, general anxiety, obsessive compulsiveness, and post-traumatic stress.

    Science.gov (United States)

    Boelen, Paul A; Huntjens, Rafaele J C; van den Hout, Marcel A

    2014-01-01

    Reduced memory specificity is associated with depression, post-traumatic stress disorder (PTSD), and some other forms of psychopathology. Reduced memory specificity is also associated with reduced specificity of envisioned future events. Research in this area has mostly relied on cue-word methods that include explicit instructions to develop specific memories of future events. These methods are limited in their ability to assess how participants habitually remember the past and imagine the future when the specificity constraints inherent in the cue-word task are removed. Sentence completions tasks have been developed that can be used to assess habitual patterns of memory and prospection. Little is known about the association of habitual memory and prospection with concurrently and prospectively assessed psychopathology. In the current study 142 participants completed sentence completion tasks tapping habitual memory and prospection at baseline and completed measures tapping psychological symptoms at baseline and 1 year later. Among other things, it was found that reduced memory specificity (but not reduced future specificity) was associated with concurrent and later depression, as well as with symptom levels of PTSD tapped 1 year beyond baseline.

  2. A study on the development of photoelastic experimental hybrid method for colour isochromatics (I)

    International Nuclear Information System (INIS)

    Hawong, Jai Sug; Nam, Jeong Hwan; Kim, Kyo Hyoung; Kwon, O Sung; Kwon, Gun; Park, Sung Han

    2010-01-01

    Isochromatics obtained from photoelastic experiment shows the stress distributions of the full field of a structure under load. Therefore, stress distributions of the structure can be read at a glance through isochromatics. Many experimental data can be obtained from isochromatics which are then used in various photoelastic experimental hybrid methods for stress analysis. Monochromatic light has however, until now been used in the photoelastic experimental hybrid method to produce black and white isochromatics. The use of black and white isochromatics in photoelastic experimental hybrid method for black and white isochromatics requires high fringe orders in order to obtain sufficient experimental data for photoelastic hybrid techniques. Accordingly, this paper develops the photoelastic experimental hybrid method for color isochromatics in which a fringe order of 1 is enough to gather the experimental data of the photoelastic experimental hybrid method. The method was applied to validate stress concentration problems. Experimental results from this study indicated that the photoelastic experimental hybrid method for color isochromatics is more precise than the photoelastic experimental hybrid method for black and white isochromatics. The use of few fringe orders in photoelastic experimental hybrid method for color isochromatics can offer significant advantages in stress analysis of real components using reflective-type photoelastic experimental method

  3. Henkin and Hybrid Logic

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Huertas, Antonia; Manzano, Maria

    2014-01-01

    Leon Henkin was not a modal logician, but there is a branch of modal logic that has been deeply influenced by his work. That branch is hybrid logic, a family of logics that extend orthodox modal logic with special proposition symbols (called nominals) that name worlds. This paper explains why...... Henkin’s techniques are so important in hybrid logic. We do so by proving a completeness result for a hybrid type theory called HTT, probably the strongest hybrid logic that has yet been explored. Our completeness result builds on earlier work with a system called BHTT, or basic hybrid type theory...... is due to the first-order perspective, which lies at the heart of Henin’s best known work and hybrid logic....

  4. Heavy Duty Diesel Truck and Bus Hybrid Powertrain Study

    Science.gov (United States)

    2012-03-01

    Electric Vehicles to supply battery modules for Smith’s lineup of zero-emission, all-electric commercial vehicles (CVs). A123 expects to begin...hybrids may have generally improved reliability compared to conventional diesel vehicles, their maintenance procedures are specialized. Hybrid

  5. Hybrid Action Systems

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    a differential action, which allows differential equations as primitive actions. The extension allows us to model hybrid systems with both continuous and discrete behaviour. The main result of this paper is an extension of such a hybrid action system with parallel composition. The extension does not change...... the original meaning of the parallel composition, and therefore also the ordinary action systems can be composed in parallel with the hybrid action systems....

  6. Nanoscale Organic Hybrid Electrolytes

    KAUST Repository

    Nugent, Jennifer L.

    2010-08-20

    Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Nanoscale Organic Hybrid Electrolytes

    KAUST Repository

    Nugent, Jennifer L.; Moganty, Surya S.; Archer, Lynden A.

    2010-01-01

    Nanoscale organic hybrid electrolytes are composed of organic-inorganic hybrid nanostructures, each with a metal oxide or metallic nanoparticle core densely grafted with an ion-conducting polyethylene glycol corona - doped with lithium salt. These materials form novel solvent-free hybrid electrolytes that are particle-rich, soft glasses at room temperature; yet manifest high ionic conductivity and good electrochemical stability above 5V. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. HYBRID VEHICLE CONTROL SYSTEM

    Directory of Open Access Journals (Sweden)

    V. Dvadnenko

    2016-06-01

    Full Text Available The hybrid vehicle control system includes a start–stop system for an internal combustion engine. The system works in a hybrid mode and normal vehicle operation. To simplify the start–stop system, there were user new possibilities of a hybrid car, which appeared after the conversion. Results of the circuit design of the proposed system of basic blocks are analyzed.

  9. Hybrid radiator cooling system

    Science.gov (United States)

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  10. Hybrid metric-Palatini stars

    Science.gov (United States)

    Danilǎ, Bogdan; Harko, Tiberiu; Lobo, Francisco S. N.; Mak, M. K.

    2017-02-01

    We consider the internal structure and the physical properties of specific classes of neutron, quark and Bose-Einstein condensate stars in the recently proposed hybrid metric-Palatini gravity theory, which is a combination of the metric and Palatini f (R ) formalisms. It turns out that the theory is very successful in accounting for the observed phenomenology, since it unifies local constraints at the Solar System level and the late-time cosmic acceleration, even if the scalar field is very light. In this paper, we derive the equilibrium equations for a spherically symmetric configuration (mass continuity and Tolman-Oppenheimer-Volkoff) in the framework of the scalar-tensor representation of the hybrid metric-Palatini theory, and we investigate their solutions numerically for different equations of state of neutron and quark matter, by adopting for the scalar field potential a Higgs-type form. It turns out that the scalar-tensor definition of the potential can be represented as an Clairaut differential equation, and provides an explicit form for f (R ) given by f (R )˜R +Λeff, where Λeff is an effective cosmological constant. Furthermore, stellar models, described by the stiff fluid, radiation-like, bag model and the Bose-Einstein condensate equations of state are explicitly constructed in both general relativity and hybrid metric-Palatini gravity, thus allowing an in-depth comparison between the predictions of these two gravitational theories. As a general result it turns out that for all the considered equations of state, hybrid gravity stars are more massive than their general relativistic counterparts. Furthermore, two classes of stellar models corresponding to two particular choices of the functional form of the scalar field (constant value, and logarithmic form, respectively) are also investigated. Interestingly enough, in the case of a constant scalar field the equation of state of the matter takes the form of the bag model equation of state describing

  11. Toronto hybrid taxi pilot

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, M. [CrossChasm Technologies, Cambridge, ON (Canada); Marans, B. [Toronto Atmospheric Fund, ON (Canada)

    2009-10-15

    This paper provided details of a hybrid taxi pilot program conducted to compare the on-road performance of Toyota Camry hybrid vehicles against conventional vehicles over a 1-year period in order to determine the business case and air emission reductions associated with the use of hybrid taxi cabs. Over 750,000 km worth of fuel consumption was captured from 10 Toyota Camry hybrids, a Toyota Prius, and 5 non-hybrid Camry vehicles over an 18-month period. The average real world fuel consumption for the taxis demonstrated that the Toyota Prius has the lowest cost of ownership, while the non-hybrid Camry has the highest cost of ownership. Carbon dioxide (CO{sub 2}) reductions associated with the 10 Camry hybrid taxis were calculated at 236 tonnes over a 7-year taxi service life. Results suggested that the conversion of Toronto's 5680 taxis would yield annual CO{sub 2} emission reductions of over 19,000 tonnes. All hybrid purchasers identified themselves as highly likely to purchase a hybrid again. 5 tabs., 9 figs.

  12. Managing hybrid marketing systems.

    Science.gov (United States)

    Moriarty, R T; Moran, U

    1990-01-01

    As competition increases and costs become critical, companies that once went to market only one way are adding new channels and using new methods - creating hybrid marketing systems. These hybrid marketing systems hold the promise of greater coverage and reduced costs. But they are also hard to manage; they inevitably raise questions of conflict and control: conflict because marketing units compete for customers; control because new indirect channels are less subject to management authority. Hard as they are to manage, however, hybrid marketing systems promise to become the dominant design, replacing the "purebred" channel strategy in all kinds of businesses. The trick to managing the hybrid is to analyze tasks and channels within and across a marketing system. A map - the hybrid grid - can help managers make sense of their hybrid system. What the chart reveals is that channels are not the basic building blocks of a marketing system; marketing tasks are. The hybrid grid forces managers to consider various combinations of channels and tasks that will optimize both cost and coverage. Managing conflict is also an important element of a successful hybrid system. Managers should first acknowledge the inevitability of conflict. Then they should move to bound it by creating guidelines that spell out which customers to serve through which methods. Finally, a marketing and sales productivity (MSP) system, consisting of a central marketing database, can act as the central nervous system of a hybrid marketing system, helping managers create customized channels and service for specific customer segments.

  13. Toronto hybrid taxi pilot

    International Nuclear Information System (INIS)

    Stevens, M.; Marans, B.

    2009-10-01

    This paper provided details of a hybrid taxi pilot program conducted to compare the on-road performance of Toyota Camry hybrid vehicles against conventional vehicles over a 1-year period in order to determine the business case and air emission reductions associated with the use of hybrid taxi cabs. Over 750,000 km worth of fuel consumption was captured from 10 Toyota Camry hybrids, a Toyota Prius, and 5 non-hybrid Camry vehicles over an 18-month period. The average real world fuel consumption for the taxis demonstrated that the Toyota Prius has the lowest cost of ownership, while the non-hybrid Camry has the highest cost of ownership. Carbon dioxide (CO 2 ) reductions associated with the 10 Camry hybrid taxis were calculated at 236 tonnes over a 7-year taxi service life. Results suggested that the conversion of Toronto's 5680 taxis would yield annual CO 2 emission reductions of over 19,000 tonnes. All hybrid purchasers identified themselves as highly likely to purchase a hybrid again. 5 tabs., 9 figs.

  14. Hybrid FOSS Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Armstrong researchers are continuing their efforts to further develop FOSS technologies. A hybrid FOSS technique (HyFOSS) employs conventional continuous grating...

  15. Yield performance and stability of CMS-based triticale hybrids.

    Science.gov (United States)

    Mühleisen, Jonathan; Piepho, Hans-Peter; Maurer, Hans Peter; Reif, Jochen Christoph

    2015-02-01

    CMS-based triticale hybrids showed only marginal midparent heterosis for grain yield and lower dynamic yield stability compared to inbred lines. Hybrids of triticale (×Triticosecale Wittmack) are expected to possess outstanding yield performance and increased dynamic yield stability. The objectives of the present study were to (1) examine the optimum choice of the biometrical model to compare yield stability of hybrids versus lines, (2) investigate whether hybrids exhibit a more pronounced grain yield performance and yield stability, and (3) study optimal strategies to predict yield stability of hybrids. Thirteen female and seven male parental lines and their 91 factorial hybrids as well as 30 commercial lines were evaluated for grain yield in up to 20 environments. Hybrids were produced using a cytoplasmic male sterility (CMS)-inducing cytoplasm that originated from Triticumtimopheevii Zhuk. We found that the choice of the biometrical model can cause contrasting results and concluded that a group-by-environment interaction term should be added to the model when estimating stability variance of hybrids and lines. midparent heterosis for grain yield was on average 3 % with a range from -15.0 to 11.5 %. No hybrid outperformed the best inbred line. Hybrids had, on average, lower dynamic yield stability compared to the inbred lines. Grain yield performance of hybrids could be predicted based on midparent values and general combining ability (GCA)-predicted values. In contrast, stability variance of hybrids could be predicted only based on GCA-predicted values. We speculated that negative effects of the used CMS cytoplasm might be the reason for the low performance and yield stability of the hybrids. For this purpose a detailed study on the reasons for the drawback of the currently existing CMS system in triticale is urgently required comprising also the search of potentially alternative hybridization systems.

  16. Stress Management

    Science.gov (United States)

    Healthy Lifestyle Stress management By Mayo Clinic Staff Stress basics Stress is a normal psychological and physical reaction to the demands of life. ... some people's alarm systems rarely shut off. Stress management gives you a range of tools to reset ...

  17. Manage Stress

    Science.gov (United States)

    ... Manage Stress Print This Topic En español Manage Stress Browse Sections The Basics Overview Signs and Health ... and Health Effects What are the signs of stress? When people are under stress, they may feel: ...

  18. Stress Incontinence

    Science.gov (United States)

    Stress incontinence Overview Urinary incontinence is the unintentional loss of urine. Stress incontinence happens when physical movement or activity — such ... coughing, sneezing, running or heavy lifting — puts pressure (stress) on your bladder. Stress incontinence is not related ...

  19. Carboxylated nitrile butadiene rubber/hybrid filler composites

    Directory of Open Access Journals (Sweden)

    Ahmad Mousa

    2012-08-01

    Full Text Available The surface properties of the OSW and NLS are measured with the dynamic contact-angle technique. The x-ray photoelectron spectroscopy (XPS of the OSW reveals that the OSW possesses various reactive functional groups namely hydroxyl groups (OH. Hybrid filler from NLS and OSW were incorporated into carboxylated nitrile rubber (XNBR to produce XNBR hybrid composites. The reaction of OH groups from the OSW with COOH of the XNBR is checked by attenuated total reflectance spectra (ATR-IR of the composites. The degree of curing ΔM (maximum torque-minimum torque as a function of hybrid filler as derived from moving die rheometer (MDR is reported. The stress-strain behavior of the hybrid composites as well as the dynamic mechanical thermal analysis (DMTA is studied. Bonding quality and dispersion of the hybrid filler with and in XNBR are examined using scanning-transmission electron microscopy (STEM in SEM.

  20. Hybrid methods for cybersecurity analysis :

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Warren Leon,; Dunlavy, Daniel M.

    2014-01-01

    years to hours and days for the application of new modeling and analysis capabilities to emerging threats. The development and deployment framework has been generalized into the Hybrid Framework and incor- porated into several LDRD, WFO, and DOE/CSL projects and proposals. And most importantly, the Hybrid project has provided Sandia security analysts with new, scalable, extensible analytic capabilities that have resulted in alerts not detectable using their previous work ow tool sets.

  1. Exotic hybrid mesons in hard electroproduction

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2005-01-01

    We estimate the sizeable cross section for deep exclusive electroproduction of an exotic J PC =1 -+ hybrid meson in the Bjorken regime. The production amplitude scales like the one for usual meson electroproduction, i.e., as 1/Q 2 . This is due to the nonvanishing leading twist distribution amplitude for the hybrid meson, which may be normalized thanks to its relation to the energy-momentum tensor and to the QCD sum rules technique. The hard amplitude is considered up to next-to-leading order in α S and we explore the consequences of fixing the renormalization scale ambiguity through the Brodsky-Lepage-Mackenzie (BLM) procedure. We study the particular case where the hybrid meson decays through a πη meson pair. We discuss the πη generalized distribution amplitude and then calculate the production amplitude for this process. We propose a forward-backward asymmetry in the production of π and η mesons as a signal for the hybrid meson production. We briefly comment on hybrid electroproduction at very high energy, in the diffractive limit where a QCD Odderon exchange mechanism should dominate. The conclusion of our study is that hard electroproduction is a promising way to study exotic hybrid mesons, in particular, at JLAB, HERA (HERMES), or CERN (Compass)

  2. The hybrid electric vehicle revolution, off road

    Energy Technology Data Exchange (ETDEWEB)

    Wood, B.E. [ePower Technologies (United States)

    2004-07-01

    In this presentation the author presents concepts and details of hybrid vehicles in general, including their benefits, then describes off-road hybrid vehicles. Hybrid vehicles have been experimented with for over a century. Demonstrator vehicles include a diesel-electric tractor, an electric lawn tractor, a hybrid snow thrower, and a hybrid wheel loader. A duty cycle for the loader is shown with battery-assisted acceleration, and regenerative braking. Both of these keep the size of the engine small, the loads on it less variable, thus improving fuel economy. A hybrid excavator and its duty cycle is shown. A fuel cell lift truck that is currently in design is illustrated. The author then describes the possibilities of the hydrogen economy where sourcing and infrastructure are yet to be demonstrated on a commercial scale. The author predicts that off-road hydrogen fuel cell vehicles will be commercially viable five years before on-road applications. The author predicts hydrogen sourced from biogas, photovoltaics, and wind power. tabs, figs.

  3. Original Framework for Optimizing Hybrid Energy Supply

    Directory of Open Access Journals (Sweden)

    Amevi Acakpovi

    2016-01-01

    Full Text Available This paper proposes an original framework for optimizing hybrid energy systems. The recent growth of hybrid energy systems in remote areas across the world added to the increasing cost of renewable energy has triggered the inevitable development of hybrid energy systems. Hybrid energy systems always pose a problem of optimization of cost which has been approached with different perspectives in the recent past. This paper proposes a framework to guide the techniques of optimizing hybrid energy systems in general. The proposed framework comprises four stages including identification of input variables for energy generation, establishment of models of energy generation by individual sources, development of artificial intelligence, and finally summation of selected sources. A case study of a solar, wind, and hydro hybrid system was undertaken with a linear programming approach. Substantial results were obtained with regard to how load requests were constantly satisfied while minimizing the cost of electricity. The developed framework gained its originality from the fact that it has included models of individual sources of energy that even make the optimization problem more complex. This paper also has impacts on the development of policies which will encourage the integration and development of renewable energies.

  4. Review of the current status of linear hybrid reactor concepts

    International Nuclear Information System (INIS)

    Schultz, K.R.

    1977-07-01

    A review was made of the current status of linear fusion-fission hybrid reactor design studies in the USA. The linear hybrid reactor concepts reviewed include the linear theta-pinch hybrid reactor being studied at Los Alamos Scientific Laboratory, the electron beam-heated solenoid hybrid reactor under development at Physics International Co., the laser-heated solenoid hybrid reactor being investigated at Mathematical Sciences Northwest, Inc., and the linear fusion waste burning reactor being studied at General Atomic Company. The discussion addresses confinement and heating mechanisms for each concept, as well as the hybrid blanket designs. The current state of the four reactor designs is summarized and the performance of the various concepts compared

  5. Comparative genomic hybridization.

    Science.gov (United States)

    Pinkel, Daniel; Albertson, Donna G

    2005-01-01

    Altering DNA copy number is one of the many ways that gene expression and function may be modified. Some variations are found among normal individuals ( 14, 35, 103 ), others occur in the course of normal processes in some species ( 33 ), and still others participate in causing various disease states. For example, many defects in human development are due to gains and losses of chromosomes and chromosomal segments that occur prior to or shortly after fertilization, whereas DNA dosage alterations that occur in somatic cells are frequent contributors to cancer. Detecting these aberrations, and interpreting them within the context of broader knowledge, facilitates identification of critical genes and pathways involved in biological processes and diseases, and provides clinically relevant information. Over the past several years array comparative genomic hybridization (array CGH) has demonstrated its value for analyzing DNA copy number variations. In this review we discuss the state of the art of array CGH and its applications in medical genetics and cancer, emphasizing general concepts rather than specific results.

  6. A new type of hybrid vehicle in Japan; Un nouveau type de vehicule hybride au Japon

    Energy Technology Data Exchange (ETDEWEB)

    Henry, P.

    2004-04-01

    During the 37. edition of the Tokyo Motor Show in October 2003, several fuel cell hybrid vehicles were presented by Japanese car makers who grant considerable budgets to develop less polluting vehicles. The trend chosen by Japanese car manufacturers concerns the hybrid system combining fuel cell and battery. Stress has been put also on intelligent systems for navigation and safety but also on the design and comfort. However, even if the environment protection is the main challenge of the Japanese automotive industry, the driving pleasure remains the most profitable medium-term market to be exploitable by industrialists. (J.S.)

  7. Hybrid-Source Impedance Networks

    DEFF Research Database (Denmark)

    Li, Ding; Gao, Feng; Loh, Poh Chiang

    2010-01-01

    Hybrid-source impedance networks have attracted attention among researchers because of their flexibility in performing buck-boost energy conversion. To date, three distinct types of impedance networks can be summarized for implementing voltage-type inverters with another three types summarized...... for current-type inverters. These impedance networks can in principle be combined into two generic network entities, before multiple of them can further be connected together by applying any of the two proposed generalized cascading concepts. The resulting two-level and three-level inverters implemented using...

  8. Hybridization in geese

    NARCIS (Netherlands)

    Ottenburghs, Jente; Hooft, van Pim; Wieren, van Sipke E.; Ydenberg, Ronald C.; Prins, Herbert H.T.

    2016-01-01

    The high incidence of hybridization in waterfowl (ducks, geese and swans) makes this bird group an excellent study system to answer questions related to the evolution and maintenance of species boundaries. However, knowledge on waterfowl hybridization is biased towards ducks, with a large

  9. Mirror hybrid reactor studies

    International Nuclear Information System (INIS)

    Bender, D.J.

    1978-01-01

    The hybrid reactor studies are reviewed. The optimization of the point design and work on a reference design are described. The status of the nuclear analysis of fast spectrum blankets, systems studies for fissile fuel producing hybrid reactor, and the mechanical design of the machine are reviewed

  10. Hybrid Universities in Malaysia

    Science.gov (United States)

    Lee, Molly; Wan, Chang Da; Sirat, Morshidi

    2017-01-01

    Are Asian universities different from those in Western countries? Premised on the hypothesis that Asian universities are different because of hybridization between Western academic models and local traditional cultures, this paper investigates the hybrid characteristics in Malaysian universities resulting from interaction between contemporary…

  11. Cardiac hybrid imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

    2014-05-15

    Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)

  12. Hybrid Shipboard Microgrids

    DEFF Research Database (Denmark)

    Othman @ Marzuki, Muzaidi Bin; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    Strict regulation on emissions of air pollutants imposed by the maritime authorities has led to the introduction of hybrid microgrids to the shipboard power systems (SPSs) which acts toward energy efficient ships with less pollution. A hybrid energy system can include different means of generation...

  13. Hybrid intelligent engineering systems

    CERN Document Server

    Jain, L C; Adelaide, Australia University of

    1997-01-01

    This book on hybrid intelligent engineering systems is unique, in the sense that it presents the integration of expert systems, neural networks, fuzzy systems, genetic algorithms, and chaos engineering. It shows that these new techniques enhance the capabilities of one another. A number of hybrid systems for solving engineering problems are presented.

  14. Editorial: Hybrid Systems

    DEFF Research Database (Denmark)

    Olderog, Ernst-Rüdiger; Ravn, Anders Peter

    2007-01-01

    An introduction to three papers in a special issue on Hybrid Systems. These paper were first presented at an IFIP WG 2.2 meeting in Skagen 2005.......An introduction to three papers in a special issue on Hybrid Systems. These paper were first presented at an IFIP WG 2.2 meeting in Skagen 2005....

  15. Natural and sexual selection against hybrid flycatchers

    NARCIS (Netherlands)

    Svedin, Nina; Wiley, Chris; Veen, Thor; Gustafsson, Lars; Qvarnstrom, Anna

    2008-01-01

    While sexual selection is generally assumed to quickly cause or strengthen prezygotic barriers between sister species, its role in causing postzygotic isolation, through the unattractiveness of intermediate hybrids, is less often examined. Combining 24 years of pedigree data and recently developed

  16. Oxidative Stress in Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Varsha Shukla

    2011-01-01

    Full Text Available It has been demonstrated that oxidative stress has a ubiquitous role in neurodegenerative diseases. Major source of oxidative stress due to reactive oxygen species (ROS is related to mitochondria as an endogenous source. Although there is ample evidence from tissues of patients with neurodegenerative disorders of morphological, biochemical, and molecular abnormalities in mitochondria, it is still not very clear whether the oxidative stress itself contributes to the onset of neurodegeneration or it is part of the neurodegenerative process as secondary manifestation. This paper begins with an overview of how oxidative stress occurs, discussing various oxidants and antioxidants, and role of oxidative stress in diseases in general. It highlights the role of oxidative stress in neurodegenerative diseases like Alzheimer's, Parkinson's, and Huntington's diseases and amyotrophic lateral sclerosis. The last part of the paper describes the role of oxidative stress causing deregulation of cyclin-dependent kinase 5 (Cdk5 hyperactivity associated with neurodegeneration.

  17. Course on hybrid calculation

    International Nuclear Information System (INIS)

    Weill, J.; Tellier; Bonnemay; Craigne; Chareton; Di Falco

    1969-02-01

    After a definition of hybrid calculation (combination of analogue and digital calculation) with a distinction between series and parallel hybrid computing, and a description of a hybrid computer structure and of task sharing between computers, this course proposes a description of hybrid hardware used in Saclay and Cadarache computing centres, and of operations performed by these systems. The next part addresses issues related to programming languages and software. The fourth part describes how a problem is organised for its processing on these computers. Methods of hybrid analysis are then addressed: resolution of optimisation problems, of partial differential equations, and of integral equations by means of different methods (gradient, maximum principle, characteristics, functional approximation, time slicing, Monte Carlo, Neumann iteration, Fischer iteration)

  18. Stress in Professional Classes: Causes, Manifestations, Coping.

    Science.gov (United States)

    Endres, Fred F.

    1992-01-01

    Investigates whether students in professional journalism and mass communication classes experience class-related stress, what factors contribute to the stress, and whether that stress changes over time. Finds that students perceive stress in their professional course work, and reveals general stress patterns over the 15-week semester. (SR)

  19. Iterative Reconstruction Methods for Hybrid Inverse Problems in Impedance Tomography

    DEFF Research Database (Denmark)

    Hoffmann, Kristoffer; Knudsen, Kim

    2014-01-01

    For a general formulation of hybrid inverse problems in impedance tomography the Picard and Newton iterative schemes are adapted and four iterative reconstruction algorithms are developed. The general problem formulation includes several existing hybrid imaging modalities such as current density...... impedance imaging, magnetic resonance electrical impedance tomography, and ultrasound modulated electrical impedance tomography, and the unified approach to the reconstruction problem encompasses several algorithms suggested in the literature. The four proposed algorithms are implemented numerically in two...

  20. Propagation of singularities for linearised hybrid data impedance tomography

    DEFF Research Database (Denmark)

    Bal, Guillaume; Hoffmann, Kristoffer; Knudsen, Kim

    2017-01-01

    For a general formulation of linearised hybrid inverse problems in impedance tomography, the qualitative properties of the solutions are analysed. Using an appropriate scalar pseudo-differential formulation, the problems are shown to permit propagating singularities under certain non-elliptic con......For a general formulation of linearised hybrid inverse problems in impedance tomography, the qualitative properties of the solutions are analysed. Using an appropriate scalar pseudo-differential formulation, the problems are shown to permit propagating singularities under certain non...

  1. MODELLING AND CONTROL OF POWER-SPLIT HYBRID ELECTRIC VEHICLE USING FUZZY LOGIC METHOD

    OpenAIRE

    Mohammadpour, Ebrahim; Khajavi, Mehrdad Nouri

    2014-01-01

    Nowadays, automotive manufactures increasingly have lead to development of hybrid vehicles due to energy consumption growing and increased emissions. the power-split hybrids due to the simultaneous using of speed and torque couplings has integrated advantage of series and parallel hybrid systems and minimize their disadvantages , however the power-split hybrids control strategy is far more complex than other types. Generally the control strategy tries to use the optimize operating point of HE...

  2. Genetic incompatibility dampens hybrid fertility more than hybrid viability: yeast as a case study.

    Directory of Open Access Journals (Sweden)

    Meibo Xu

    Full Text Available Genetic incompatibility is believed to be the major cause of postzygotic reproductive isolation. Despite huge efforts seeking for speciation-related incompatibilities in the past several decades, a general understanding of how genetic incompatibility evolves in affecting hybrid fitness is not available, primarily due to the fact that the number of known incompatibilities is small. Instead of further mapping specific incompatible genes, in this paper we aimed to know the overall effects of incompatibility on fertility and viability, the two aspects of fitness, by examining 89 gametes produced by yeast S. cerevisiae-S. paradoxus F1 hybrids. Homozygous F2 hybrids formed by autodiploidization of F1 gametes were subject to tests for growth rate and sporulation efficiency. We observed much stronger defects in sporulation than in clonal growth for every single F2 hybrid strain, indicating that genetic incompatibility affects hybrid fertility more than hybrid viability in yeast. We related this finding in part to the fast-evolving nature of meiosis-related genes, and proposed that the generally low expression levels of these genes might be a cause of the observation.

  3. Probabilistic Analysis Methods for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Brohus, Henrik; Frier, Christian; Heiselberg, Per

    This paper discusses a general approach for the application of probabilistic analysis methods in the design of ventilation systems. The aims and scope of probabilistic versus deterministic methods are addressed with special emphasis on hybrid ventilation systems. A preliminary application...... of stochastic differential equations is presented comprising a general heat balance for an arbitrary number of loads and zones in a building to determine the thermal behaviour under random conditions....

  4. Hybrid uncertainty-based design optimization and its application to hybrid rocket motors for manned lunar landing

    Directory of Open Access Journals (Sweden)

    Hao Zhu

    2017-04-01

    Full Text Available Design reliability and robustness are getting increasingly important for the general design of aerospace systems with many inherently uncertain design parameters. This paper presents a hybrid uncertainty-based design optimization (UDO method developed from probability theory and interval theory. Most of the uncertain design parameters which have sufficient information or experimental data are classified as random variables using probability theory, while the others are defined as interval variables with interval theory. Then a hybrid uncertainty analysis method based on Monte Carlo simulation and Taylor series interval analysis is developed to obtain the uncertainty propagation from the design parameters to system responses. Three design optimization strategies, including deterministic design optimization (DDO, probabilistic UDO and hybrid UDO, are applied to the conceptual design of a hybrid rocket motor (HRM used as the ascent propulsion system in Apollo lunar module. By comparison, the hybrid UDO is a feasible method and can be effectively applied to the general design of aerospace systems.

  5. Hybrid uncertainty-based design optimization and its application to hybrid rocket motors for manned lunar landing

    Institute of Scientific and Technical Information of China (English)

    Zhu Hao; Tian Hui; Cai Guobiao

    2017-01-01

    Design reliability and robustness are getting increasingly important for the general design of aerospace systems with many inherently uncertain design parameters. This paper presents a hybrid uncertainty-based design optimization (UDO) method developed from probability theory and interval theory. Most of the uncertain design parameters which have sufficient information or experimental data are classified as random variables using probability theory, while the others are defined as interval variables with interval theory. Then a hybrid uncertainty analysis method based on Monte Carlo simulation and Taylor series interval analysis is developed to obtain the uncer-tainty propagation from the design parameters to system responses. Three design optimization strategies, including deterministic design optimization (DDO), probabilistic UDO and hybrid UDO, are applied to the conceptual design of a hybrid rocket motor (HRM) used as the ascent propulsion system in Apollo lunar module. By comparison, the hybrid UDO is a feasible method and can be effectively applied to the general design of aerospace systems.

  6. Hybrid stochastic simplifications for multiscale gene networks

    Directory of Open Access Journals (Sweden)

    Debussche Arnaud

    2009-09-01

    Full Text Available Abstract Background Stochastic simulation of gene networks by Markov processes has important applications in molecular biology. The complexity of exact simulation algorithms scales with the number of discrete jumps to be performed. Approximate schemes reduce the computational time by reducing the number of simulated discrete events. Also, answering important questions about the relation between network topology and intrinsic noise generation and propagation should be based on general mathematical results. These general results are difficult to obtain for exact models. Results We propose a unified framework for hybrid simplifications of Markov models of multiscale stochastic gene networks dynamics. We discuss several possible hybrid simplifications, and provide algorithms to obtain them from pure jump processes. In hybrid simplifications, some components are discrete and evolve by jumps, while other components are continuous. Hybrid simplifications are obtained by partial Kramers-Moyal expansion 123 which is equivalent to the application of the central limit theorem to a sub-model. By averaging and variable aggregation we drastically reduce simulation time and eliminate non-critical reactions. Hybrid and averaged simplifications can be used for more effective simulation algorithms and for obtaining general design principles relating noise to topology and time scales. The simplified models reproduce with good accuracy the stochastic properties of the gene networks, including waiting times in intermittence phenomena, fluctuation amplitudes and stationary distributions. The methods are illustrated on several gene network examples. Conclusion Hybrid simplifications can be used for onion-like (multi-layered approaches to multi-scale biochemical systems, in which various descriptions are used at various scales. Sets of discrete and continuous variables are treated with different methods and are coupled together in a physically justified approach.

  7. Predominant Expression of Hybrid N-Glycans Has Distinct Cellular Roles Relative to Complex and Oligomannose N-Glycans

    Directory of Open Access Journals (Sweden)

    M. Kristen Hall

    2016-06-01

    Full Text Available Glycosylation modulates growth, maintenance, and stress signaling processes. Consequently, altered N-glycosylation is associated with reduced fitness and disease. Therefore, expanding our understanding of N-glycans in altering biological processes is of utmost interest. Herein, clustered regularly interspaced short palindromic repeats/caspase9 (CRISPR/Cas9 technology was employed to engineer a glycosylation mutant Chinese Hamster Ovary (CHO cell line, K16, which expresses predominantly hybrid type N-glycans. This newly engineered cell line enabled us to compare N-glycan effects on cellular properties of hybrid type N-glycans, to the well-established Pro−5 and Lec1 cell lines, which express complex and oligomannose types of N-glycans, respectively. Lectin binding studies revealed the predominant N-glycan expressed in K16 is hybrid type. Cell dissociation and migration assays demonstrated the greatest strength of cell–cell adhesion and fastest migratory rates for oligomannose N-glycans, and these properties decreased as oligomannose type were converted to hybrid type, and further decreased upon conversion to complex type. Next, we examined the roles of three general types of N-glycans on ectopic expression of E-cadherin, a cell–cell adhesion protein. Microscopy revealed more functional E-cadherin at the cell–cell border when N-glycans were oligomannose and these levels decreased as the oligomannose N-glycans were processed to hybrid and then to complex. Thus, we provide evidence that all three general types of N-glycans impact plasma membrane architecture and cellular properties.

  8. The disadvantages of being a hybrid during drought: A combined analysis of plant morphology, physiology and leaf proteome in maize

    Science.gov (United States)

    Benešová, Monika; Fischer, Lukáš; Haisel, Daniel; Hnilička, František; Hniličková, Helena; Jedelský, Petr L.; Kočová, Marie; Rothová, Olga; Tůmová, Lenka; Wilhelmová, Naďa

    2017-01-01

    A comparative analysis of various parameters that characterize plant morphology, growth, water status, photosynthesis, cell damage, and antioxidative and osmoprotective systems together with an iTRAQ analysis of the leaf proteome was performed in two inbred lines of maize (Zea mays L.) differing in drought susceptibility and their reciprocal F1 hybrids. The aim of this study was to dissect the parent-hybrid relationships to better understand the mechanisms of the heterotic effect and its potential association with the stress response. The results clearly showed that the four examined genotypes have completely different strategies for coping with limited water availability and that the inherent properties of the F1 hybrids, i.e. positive heterosis in morphological parameters (or, more generally, a larger plant body) becomes a distinct disadvantage when the water supply is limited. However, although a greater loss of photosynthetic efficiency was an inherent disadvantage, the precise causes and consequences of the original predisposition towards faster growth and biomass accumulation differed even between reciprocal hybrids. Both maternal and paternal parents could be imitated by their progeny in some aspects of the drought response (e.g., the absence of general protein down-regulation, changes in the levels of some carbon fixation or other photosynthetic proteins). Nevertheless, other features (e.g., dehydrin or light-harvesting protein contents, reduced chloroplast proteosynthesis) were quite unique to a particular hybrid. Our study also confirmed that the strategy for leaving stomata open even when the water supply is limited (coupled to a smaller body size and some other physiological properties), observed in one of our inbred lines, is associated with drought-resistance not only during mild drought (as we showed previously) but also during more severe drought conditions. PMID:28419152

  9. A global hybrid coupled model based on atmosphere-SST feedbacks

    Energy Technology Data Exchange (ETDEWEB)

    Cimatoribus, Andrea A.; Drijfhout, Sybren S. [Royal Netherlands Meteorological Institute, De Bilt (Netherlands); Dijkstra, Henk A. [Utrecht University, Institute for Marine and Atmospheric Research Utrecht, Utrecht (Netherlands)

    2012-02-15

    A global hybrid coupled model is developed, with the aim of studying the effects of ocean-atmosphere feedbacks on the stability of the Atlantic meridional overturning circulation. The model includes a global ocean general circulation model and a statistical atmosphere model. The statistical atmosphere model is based on linear regressions of data from a fully coupled climate model on sea surface temperature both locally and hemispherically averaged, being the footprint of Atlantic meridional overturning variability. It provides dynamic boundary conditions to the ocean model for heat, freshwater and wind-stress. A basic but consistent representation of ocean-atmosphere feedbacks is captured in the hybrid coupled model and it is more than 10 times faster than the fully coupled climate model. The hybrid coupled model reaches a steady state with a climate close to the one of the fully coupled climate model, and the two models also have a similar response (collapse) of the Atlantic meridional overturning circulation to a freshwater hosing applied in the northern North Atlantic. (orig.)

  10. Mirror hybrid (fusion--fission) reactor

    International Nuclear Information System (INIS)

    Bender, D.J.; Lee, J.D.; Neef, W.S.; Devoto, R.S.; Galloway, T.R.; Fink, J.H.; Schultz, K.R.; Culver, D.; Rao, S.

    1977-10-01

    The reference mirror hybrid reactor design performed by LLL and General Atomic is summarized. The reactor parameters have been chosen to minimize the cost of producing fissile fuel for consumption in fission power reactors. As in the past, we have emphasized the use of existing technology where possible and a minimum extrapolation of technology otherwise. The resulting reactor may thus be viewed as a comparatively near-term goal of the fusion program, and we project improved performance for the hybrid in the future as more advanced technology becomes available

  11. Stress and Protists: No life without stress.

    Science.gov (United States)

    Slaveykova, Vera; Sonntag, Bettina; Gutiérrez, Juan Carlos

    2016-08-01

    We report a summary of the symposium "Stress and Protists: No life without stress", which was held in September 2015 on the VII European Congress of Protistology in partnership with the International Society of Protistologists (Seville, Spain). We present an overview on general comments and concepts on cellular stress which can be also applied to any protist. Generally, various environmental stressors may induce similar cell responses in very different protists. Two main topics are reported in this manuscript: (i) metallic nanoparticles as environmental pollutants and stressors for aquatic protists, and (ii) ultraviolet radiation - induced stress and photoprotective strategies in ciliates. Model protists such as Chlamydomonas reinhardtii and Tetrahymena thermophila were used to assess stress caused by nanoparticles while stress caused by ultraviolet radiation was tested with free living planktonic ciliates as well as with the symbiont-bearing model ciliate Paramecium bursaria. For future studies, we suggest more intensive analyses on protist stress responses to specific environmental abiotic and/or biotic stressors at molecular and genetic levels up to ecological consequences and food web dynamics. Copyright © 2016 Elsevier GmbH. All rights reserved.

  12. Nuclear stress test

    Science.gov (United States)

    ... Persantine stress test; Thallium stress test; Stress test - nuclear; Adenosine stress test; Regadenoson stress test; CAD - nuclear stress; Coronary artery disease - nuclear stress; Angina - nuclear ...

  13. Controle genético e tolerância ao estresse de calor em populações híbridas e em cultivares de trigo Genetic control and tolerance to the heat stress in wheat hybrid population and cultivars

    Directory of Open Access Journals (Sweden)

    Moacil Alves de Souza

    2001-10-01

    Full Text Available O objetivo deste trabalho foi obter informações sobre o controle genético da produtividade de grãos de trigo sob condições de estresse de calor, o grau de tolerância ao estresse de calor de algumas cultivares e linhagens e a identificação de populações segregantes promissoras para a obtenção de linhagens adaptadas às condições da região central do Brasil. Foram avaliados 13 parentais e 40 populações provenientes de um dialelo parcial, nas gerações F1 e F2 em condições de campo, em Lavras e Patos de Minas, MG, com as semeaduras feitas no verão (fevereiro e no inverno (maio. Houve diferença de tolerância ao calor entre os parentais e entre as populações híbridas quanto ao caráter produção de grãos, e ambos os efeitos aditivos e não-aditivos foram importantes no controle genético deste caráter na presença ou ausência de calor. Apesar da ocorrência de interações populações x épocas de semeadura, a alta repetibilidade dos efeitos da capacidade geral de combinação permite inferir a possibilidade de acelerar os programas de melhoramento na região, efetuando-se a seleção tanto na época de verão quanto no inverno.The objective of this work was to get information about the genetic control of the grain yield under heat stress conditions, the tolerance of cultivar and the identification of promising segregation populations for selections of lines adapted to the conditions of the central region of Brazil. Thirteen parents and 40 populations in F1 and F2 generations derived by partial diallel crosses were evaluated. The experiments were conducted under field conditions in Lavras and Patos de Minas, MG, Brazil, sowing the seeds in the summertime (February and in the winter (May. There was difference of heat tolerance among parents and hybrid populations for grain yield character, and both additive and non-additive effects were important in the genetic control of grain yield character in the presence or absence

  14. Hybrid electric vehicles TOPTEC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-06-21

    This one-day TOPTEC session began with an overview of hybrid electric vehicle technology. Updates were given on alternative types of energy storage, APU control for low emissions, simulation programs, and industry and government activities. The keynote speech was about battery technology, a key element to the success of hybrids. The TOPEC concluded with a panel discussion on the mission of hybrid electric vehicles, with a perspective from industry and government experts from United States and Canada on their view of the role of this technology.

  15. Hybrid systems with constraints

    CERN Document Server

    Daafouz, Jamal; Sigalotti, Mario

    2013-01-01

    Control theory is the main subject of this title, in particular analysis and control design for hybrid dynamic systems.The notion of hybrid systems offers a strong theoretical and unified framework to cope with the modeling, analysis and control design of systems where both continuous and discrete dynamics interact. The theory of hybrid systems has been the subject of intensive research over the last decade and a large number of diverse and challenging problems have been investigated. Nevertheless, many important mathematical problems remain open.This book is dedicated mainly to

  16. Towers of hybrid mesons

    International Nuclear Information System (INIS)

    Semay, Claude; Buisseret, Fabien; Silvestre-Brac, Bernard

    2009-01-01

    A hybrid meson is a quark-antiquark pair in which, contrary to ordinary mesons, the gluon field is in an excited state. In the framework of constituent models, the interaction potential is assumed to be the energy of an excited string. An approximate, but accurate, analytical solution of the Schroedinger equation with such a potential is presented. When applied to hybrid charmonia and bottomonia, towers of states are predicted in which the masses are a linear function of a harmonic oscillator band number for the quark-antiquark pair. Such a formula could be a reliable guide for the experimental detection of heavy hybrid mesons.

  17. Hybrid Bloch brane

    Energy Technology Data Exchange (ETDEWEB)

    Bazeia, D.; Lima, Elisama E.M.; Losano, L. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, PB (Brazil)

    2017-02-15

    This work reports on models described by two real scalar fields coupled with gravity in the five-dimensional spacetime, with a warped geometry involving one infinite extra dimension. Through a mechanism that smoothly changes a thick brane into a hybrid brane, one investigates the appearance of hybrid branes hosting internal structure, characterized by the splitting on the energy density and the volcano potential, induced by the parameter which controls interactions between the two scalar fields. In particular, we investigate distinct symmetric and asymmetric hybrid brane scenarios. (orig.)

  18. Stress relief of transition zones

    International Nuclear Information System (INIS)

    Woodward, J.; van Rooyen, D.

    1984-01-01

    This paper considers the problem of intergranular stress corrosion cracking, initiated on the primary side, in the expansion transition region of roller expanded Alloy 600 tubing. In general it is believed that residual stresses, arising from the expansion process, are the cause of the problem. The work reported here concentrated on the identification of an optimal, in-situ stress relief treatment

  19. Hybrid war”: рolitical discourse and the international practice

    OpenAIRE

    P. A. Tsygankov

    2015-01-01

    The paper analyzes the content of the term “hybrid war” and its difference from other types of modern military conflicts; stresses that combination of military and non-military methods became a priority means in conducting the U.S. foreign policy; argues that the term “hybrid war” is exploited as a tool of anti-Russian rhetoric.

  20. Gas-Transport-Property Performance of Hybrid Carbon Molecular Sieve−Polymer Materials

    KAUST Repository

    Das, Mita; Perry, John D.; Koros, William J.

    2010-01-01

    agglomeration and residual stress, were addressed in this work, and subsequently a new membrane formation technique was developed to produce high-performing membranes. The successfully improved interfacial region of the hybrid membranes allows the sieves

  1. Exploring the tensile strain energy absorption of hybrid modified epoxies containing soft particles

    International Nuclear Information System (INIS)

    Abadyan, M.; Bagheri, R.; Kouchakzadeh, M.A.; Hosseini Kordkheili, S.A.

    2011-01-01

    Research highlights: → Two epoxy systems have been modified by combination of fine and coarse modifiers. → While both hybrid systems reveal synergistic K IC , no synergism is observed in tensile test. → It is found that coarse particles induce stress concentration in hybrid samples. → Stress concentration leads to fracture of samples at lower energy absorption levels. -- Abstract: In this paper, tensile strain energy absorption of two different hybrid modified epoxies has been systematically investigated. In one system, epoxy has been modified by amine-terminated butadiene acrylonitrile (ATBN) and hollow glass spheres as fine and coarse modifiers, respectively. The other hybrid epoxy has been modified by the combination of ATBN and recycled Tire particles. The results of fracture toughness measurement of blends revealed synergistic toughening for both hybrid systems in some formulations. However, no evidence of synergism is observed in tensile test of hybrid samples. Scanning electron microscope (SEM), transmission optical microscope (TOM) and finite element (FEM) simulation were utilized to study deformation mechanisms of hybrid systems in tensile test. It is found that coarse particles induce stress concentration in hybrid samples. This produces non-uniform strain localized regions which lead to fracture of hybrid samples at lower tensile loading and energy absorption levels.

  2. Formula hybrid SAE.

    Science.gov (United States)

    2013-09-01

    User-friendly tools are needed for undergraduates to learn about component sizing, powertrain integration, and control : strategies for student competitions involving hybrid vehicles. A TK Solver tool was developed at the University of Idaho for : th...

  3. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T [Huntington Beach, CA; Sahimi, Muhammad [Altadena, CA; Fayyaz-Najafi, Babak [Richmond, CA; Harale, Aadesh [Los Angeles, CA; Park, Byoung-Gi [Yeosu, KR; Liu, Paul K. T. [Lafayette Hill, PA

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  4. Hybrid plasmachemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lelevkin, V. M., E-mail: lelevkin44@mail.ru; Smirnova, Yu. G.; Tokarev, A. V. [Kyrgyz-Russian Slavic University (Kyrgyzstan)

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  5. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-01-01

    for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations

  6. Learning During Stressful Times

    Science.gov (United States)

    Shors, Tracey J.

    2012-01-01

    Stressful life events can have profound effects on our cognitive and motor abilities, from those that could be construed as adaptive to those not so. In this review, I discuss the general notion that acute stressful experience necessarily impairs our abilities to learn and remember. The effects of stress on operant conditioning, that is, learned helplessness, as well as those on classical conditioning procedures are discussed in the context of performance and adaptation. Studies indicating sex differences in learning during stressful times are discussed, as are those attributing different responses to the existence of multiple memory systems and nonlinear relationships. The intent of this review is to highlight the apparent plasticity of the stress response, how it might have evolved to affect both performance and learning processes, and the potential problems with interpreting stress effects on learning as either good or bad. An appreciation for its plasticity may provide new avenues for investigating its underlying neuronal mechanisms. PMID:15054128

  7. Hybrid vertical cavity laser

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2010-01-01

    A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide.......A new hybrid vertical cavity laser structure for silicon photonics is suggested and numerically investigated. It incorporates a silicon subwavelength grating as a mirror and a lateral output coupler to a silicon ridge waveguide....

  8. Human hybrid hybridoma

    Energy Technology Data Exchange (ETDEWEB)

    Tiebout, R.F.; van Boxtel-Oosterhof, F.; Stricker, E.A.M.; Zeijlemaker, W.P.

    1987-11-15

    Hybrid hybridomas are obtained by fusion of two cells, each producing its own antibody. Several authors have reported the construction of murine hybrid hybridomas with the aim to obtain bispecific monoclonal antibodies. The authors have investigated, in a model system, the feasibility of constructing a human hybrid hybridoma. They fused two monoclonal cell lines: an ouabain-sensitive and azaserine/hypoxanthine-resistant Epstein-Barr virus-transformed human cell line that produces an IgG1kappa antibody directed against tetanus toxiod and an azaserine/hypoxanthine-sensitive and ouabain-resistant human-mouse xenohybrid cell line that produces a human IgG1lambda antibody directed against hepatitis-B surface antigen. Hybrid hybridoma cells were selected in culture medium containing azaserine/hypoxanthine and ouabain. The hybrid nature of the secreted antibodies was analyzed by means of two antigen-specific immunoassay. The results show that it is possible, with the combined use of transformation and xenohybridization techniques, to construct human hybrid hybridomas that produce bispecific antibodies. Bispecific antibodies activity was measured by means of two radioimmunoassays.

  9. Systems for hybrid cars

    Science.gov (United States)

    Bitsche, Otmar; Gutmann, Guenter

    Not only sharp competition but also legislation are pushing development of hybrid drive trains. Based on conventional internal combustion engine (ICE) vehicles, these drive trains offer a wide range of benefits from reduced fuel consumption and emission to multifaceted performance improvements. Hybrid electric drive trains may also facilitate the introduction of fuel cells (FC). The battery is the key component for all hybrid drive trains, as it dominates cost and performance issues. The selection of the right battery technology for the specific automotive application is an important task with an impact on costs of development and use. Safety, power, and high cycle life are a must for all hybrid applications. The greatest pressure to reduce cost is in soft hybrids, where lead-acid embedded in a considerate management presents the cheapest solution, with a considerable improvement in performance needed. From mild to full hybridization, an improvement in specific power makes higher costs more acceptable, provided that the battery's service life is equivalent to the vehicle's lifetime. Today, this is proven for the nickel-metal hydride system. Lithium ion batteries, which make use of a multiple safety concept, and with some development anticipated, provide even better prospects in terms of performance and costs. Also, their scalability permits their application in battery electric vehicles—the basis for better performance and enhanced user acceptance. Development targets for the batteries are discussed with a focus on system aspects such as electrical and thermal management and safety.

  10. Exotic hybrid mesons in hard electroproduction

    CERN Document Server

    Anikin, I V; Szymanowski, L; Teryaev, O V; Wallon, S

    2005-01-01

    We estimate the sizeable cross section for deep exclusive electroproduction of an exotic $J^{PC}=1^{-+}$ hybrid meson in the Bjorken regime. The production amplitude scales like the one for usual meson electroproduction, i.e. as $1/Q^2$. This is due to the non-vanishing leading twist distribution amplitude for the hybrid meson, which may be normalized thanks to its relation to the energy momentum tensor and to the QCD sum rules technique. The hard amplitude is considered up to next-to-leading order in $\\alpha_{S}$ and we explore the consequences of fixing the renormalization scale ambiguity through the BLM procedure. We study the particular case where the hybrid meson decays through a $\\pi\\eta $ meson pair. We discuss the $\\pi\\eta$ generalized distribution amplitude and then calculate the production amplitude for this process. We propose a forward-backward asymmetry in the production of $\\pi$ and $\\eta$ mesons as a signal for the hybrid meson production. We briefly comment on hybrid electroproduction at very ...

  11. Arsenic-induced stress activates sulfur metabolism in different organs of garlic (Allium sativum L.) plants accompanied by a general decline of the NADPH-generating systems in roots.

    Science.gov (United States)

    Ruíz-Torres, Carmelo; Feriche-Linares, Rafael; Rodríguez-Ruíz, Marta; Palma, José M; Corpas, Francisco J

    2017-04-01

    Arsenic (As) contamination is a major environmental problem which affects most living organisms from plants to animals. This metalloid poses a health risk for humans through its accumulation in crops and water. Using garlic (Allium sativum L.) plants as model crop exposed to 200μM arsenate, a comparative study among their main organs (roots and shoots) was made. The analysis of arsenic, glutathione (GSH), phytochelatins (PCs) and lipid peroxidation contents with the activities of antioxidant enzymes (catalase, superoxide dismutase, ascorbate-glutathione cycle), and the main components of the NADPH-generating system, including glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), NADP-malic enzyme (NADP-ME) and NADP-isocitrate dehydrogenase (NADP-ICDH) was carried out. Data showed a correlation among arsenic accumulation in the different organs, PCs content and the antioxidative response, with a general decline of the NADPH-generating systems in roots. Overall, our results demonstrate that there are clear connections between arsenic uptake, increase of their As-chelating capacity in roots and a decline of antioxidative enzyme activities (catalase and the ascorbate peroxidase) whose alteration provoked As-induced oxidative stress. Thus, the data suggest that roots act as barrier of arsenic mediated by a prominent sulfur metabolism which is characterized by the biosynthesis of high amount of PCs. Copyright © 2017 Elsevier GmbH. All rights reserved.

  12. Generalized functions

    CERN Document Server

    Gelfand, I M; Graev, M I; Vilenkin, N Y; Pyatetskii-Shapiro, I I

    Volume 1 is devoted to basics of the theory of generalized functions. The first chapter contains main definitions and most important properties of generalized functions as functional on the space of smooth functions with compact support. The second chapter talks about the Fourier transform of generalized functions. In Chapter 3, definitions and properties of some important classes of generalized functions are discussed; in particular, generalized functions supported on submanifolds of lower dimension, generalized functions associated with quadratic forms, and homogeneous generalized functions are studied in detail. Many simple basic examples make this book an excellent place for a novice to get acquainted with the theory of generalized functions. A long appendix presents basics of generalized functions of complex variables.

  13. Hybrid Propulsion Demonstration Program 250K Hybrid Motor

    Science.gov (United States)

    Story, George; Zoladz, Tom; Arves, Joe; Kearney, Darren; Abel, Terry; Park, O.

    2003-01-01

    The Hybrid Propulsion Demonstration Program (HPDP) program was formed to mature hybrid propulsion technology to a readiness level sufficient to enable commercialization for various space launch applications. The goal of the HPDP was to develop and test a 250,000 pound vacuum thrust hybrid booster in order to demonstrate hybrid propulsion technology and enable manufacturing of large hybrid boosters for current and future space launch vehicles. The HPDP has successfully conducted four tests of the 250,000 pound thrust hybrid rocket motor at NASA's Stennis Space Center. This paper documents the test series.

  14. Hybrid carrageenans: isolation, chemical structure, and gel properties.

    Science.gov (United States)

    Hilliou, Loic

    2014-01-01

    Hybrid carrageenan is a special class of carrageenan with niche application in food industry. This polysaccharide is extracted from specific species of seaweeds belonging to the Gigartinales order. This chapter focuses on hybrid carrageenan showing the ability to form gels in water, which is known in the food industry as weak kappa or kappa-2 carrageenan. After introducing the general chemical structure defining hybrid carrageenan, the isolation of the polysaccharide will be discussed focusing on the interplay between seaweed species, extraction parameters, and the hybrid carrageenan chemistry. Then, the rheological experiments used to determine the small and large deformation behavior of gels will be detailed before reviewing the relationships between gel properties and hybrid carrageenan chemistry. © 2014 Elsevier Inc. All rights reserved.

  15. Numerical analysis of stiffener for hybrid drive unite

    Directory of Open Access Journals (Sweden)

    Jakubovičová Lenka

    2018-01-01

    Full Text Available The matter of this article is a stress-strain analysis of hybrid drive prototype unit connected directly to convention Concrete Transit Mixer Gearbox. The unite was developed with intention to do field test on existing convection machines with possibility to use existing interfaces. The hybrid drive unit consists from electric and hydrostatic motor connected through addition mechanical transmission gearbox. The question is if today standard interface is good enough or need additional support a “stiffener”. Two engineering design were analysed. The first one includes using the stiffener to fixate the construction of hybrid drive unite connected to the planetary gear. The second one is without the stiffener. For strain-stress analysis, a finite element software ANSYS Workbench was used.

  16. Chemical hybridizing agent SQ-1-induced male sterility in Triticum aestivum L.: a comparative analysis of the anther proteome.

    Science.gov (United States)

    Liu, Hongzhan; Zhang, Gaisheng; Wang, Junsheng; Li, Jingjing; Song, Yulong; Qiao, Lin; Niu, Na; Wang, Junwei; Ma, Shoucai; Li, Lili

    2018-01-05

    Heterosis is widely used to increase the yield of many crops. However, as wheat is a self-pollinating crop, hybrid breeding is not so successful in this organism. Even though male sterility induced by chemical hybridizing agents is an important aspect of crossbreeding, the mechanisms by which these agents induce male sterility in wheat is not well understood. We performed proteomic analyses using the wheat Triticum aestivum L.to identify those proteins involved in physiological male sterility (PHYMS) induced by the chemical hybridizing agent CHA SQ-1. A total of 103 differentially expressed proteins were found by 2D-PAGE and subsequently identified by MALDI-TOF/TOF MS/MS. In general, these proteins had obvious functional tendencies implicated in carbohydrate metabolism, oxidative stress and resistance, protein metabolism, photosynthesis, and cytoskeleton and cell structure. In combination with phenotypic, tissue section, and bioinformatics analyses, the identified differentially expressed proteins revealed a complex network behind the regulation of PHYMS and pollen development. Accordingly, we constructed a protein network of male sterility in wheat, drawing relationships between the 103 differentially expressed proteins and their annotated biological pathways. To further validate our proposed protein network, we determined relevant physiological values and performed real-time PCR assays. Our proteomics based approach has enabled us to identify certain tendencies in PHYMS anthers. Anomalies in carbohydrate metabolism and oxidative stress, together with premature tapetum degradation, may be the cause behind carbohydrate starvation and male sterility in CHA SQ-1 treated plants. Here, we provide important insight into the mechanisms underlying CHA SQ-1-induced male sterility. Our findings have practical implications for the application of hybrid breeding in wheat.

  17. Disease processes as hybrid dynamical systems

    Directory of Open Access Journals (Sweden)

    Pietro Liò

    2012-08-01

    Full Text Available We investigate the use of hybrid techniques in complex processes of infectious diseases. Since predictive disease models in biomedicine require a multiscale approach for understanding the molecule-cell-tissue-organ-body interactions, heterogeneous methodologies are often employed for describing the different biological scales. Hybrid models provide effective means for complex disease modelling where the action and dosage of a drug or a therapy could be meaningfully investigated: the infection dynamics can be classically described in a continuous fashion, while the scheduling of multiple treatment discretely. We define an algebraic language for specifying general disease processes and multiple treatments, from which a semantics in terms of hybrid dynamical system can be derived. Then, the application of control-theoretic tools is proposed in order to compute the optimal scheduling of multiple therapies. The potentialities of our approach are shown in the case study of the SIR epidemic model and we discuss its applicability on osteomyelitis, a bacterial infection affecting the bone remodelling system in a specific and multiscale manner. We report that formal languages are helpful in giving a general homogeneous formulation for the different scales involved in a multiscale disease process; and that the combination of hybrid modelling and control theory provides solid grounds for computational medicine.

  18. Fusion-fission hybrid reactors

    International Nuclear Information System (INIS)

    Greenspan, E.

    1984-01-01

    This chapter discusses the range of characteristics attainable from hybrid reactor blankets; blanket design considerations; hybrid reactor designs; alternative fuel hybrid reactors; multi-purpose hybrid reactors; and hybrid reactors and the energy economy. Hybrid reactors are driven by a fusion neutron source and include fertile and/or fissile material. The fusion component provides a copious source of fusion neutrons which interact with a subcritical fission component located adjacent to the plasma or pellet chamber. Fissile fuel and/or energy are the main products of hybrid reactors. Topics include high F/M blankets, the fissile (and tritium) breeding ratio, effects of composition on blanket properties, geometrical considerations, power density and first wall loading, variations of blanket properties with irradiation, thermal-hydraulic and mechanical design considerations, safety considerations, tokamak hybrid reactors, tandem-mirror hybrid reactors, inertial confinement hybrid reactors, fusion neutron sources, fissile-fuel and energy production ability, simultaneous production of combustible and fissile fuels, fusion reactors for waste transmutation and fissile breeding, nuclear pumped laser hybrid reactors, Hybrid Fuel Factories (HFFs), and scenarios for hybrid contribution. The appendix offers hybrid reactor fundamentals. Numerous references are provided

  19. Characterization of the Bulgarian sunflower hybrid Valin

    Directory of Open Access Journals (Sweden)

    G. Georgiev

    2016-09-01

    Full Text Available Abstract. A male sterile two-linear sunflower hybrid was developed at Dobrudzha Agricultural Institute – General Toshevo using the method of inter-linear hybridization. The mother component is line 10517 which possesses cytoplasmic male sterility, and the father component is line 10595R, a fertility restorer of branched type. Both parental forms have very good general and specific combining ability. Hybrid Valin is medium early, with vegetation period of 110 – 115 days, plant height 165 – 175 cm and head diameter 17 – 18 cm. The percent of kernel in seed is within the range of 65 – 73%. Seeds have absolute weight 50 – 55 g, and oil content in seed is 46 – 50%. The hybrid is resistant to lodging and moderately resistant to phoma and phomopsis. The resistance to downy mildew is as high as 95 % up to race 700, and the resistance to the parasite Orobanche is 100% (races A-F. In the breeding fields of DAI the hybrid went through threeyear testing according to a scheme and growing technology approved for this crop. During the first two years of the control testing it exceeded the mean standard by seed yield with 11.0% and 14.4%, respectively. During the third year, hybrid Valin was above the mean standard with 10.9% by seed yield and with 6.6% by oil yield in a unified competitive varietal testing. The maximum yield obtained at DAI was 4483 kg/ha, and the maximum oil content was 50.1%. In 2007 and 2008 hybrid Valin went through official testing within the structure of the Executive Agency of Variety Testing, Field Inspection and Seed Control of Bulgaria. By the index seed yield, the exceeding of the mean standard was 23.6 % in the first year, and in the second the yield was with 1.4 % below the standard. Oil content was a little below the standard in both years. The aim of this investigation was to make as full as possible a characterization of the new registered sunflower hybrid Valin on the base of biological, phytopatological and

  20. Coupling of slow waves near the lower hybrid frequency in JET

    International Nuclear Information System (INIS)

    Litaudon, X.; Moreau, D.

    1990-01-01

    The physical properties of the JET lower hybrid antenna have been investigated numerically with a two-dimensional computer code based on the linear coupling theory. The antenna is made from an array of multijunction units which divide the incident power along the toroidal direction. The main properties of this new coupler are investigated and compared with those of the conventional grills generally used in previous lower hybrid experiments. In the light of this study, the general design of the multijunction antenna is presented; the importance of the geometrical parameters of the multijunction unit (e.g. choice of the location of the E-plane junctions, septum width between waveguides) is stressed. These parameters are optimized and their values are taken into account in launcher manufacturing. With such an optimization, the electric field enhancement in each secondary waveguide is minimized for an electron density at the launcher of about 10 18 m -3 , the power reflection coefficient is below 1.5% and the 'n parallel -weighted antenna directivity' is expected to lie between 60% and 70% in a large range of plasma densities around the optimum density. By using two shorted passive waveguides on each side of the antenna, the edge effects are reduced. The effect of the accessibility limit on coupling is also investigated. (author). 18 refs, 19 figs

  1. Research on Hybrid Vehicle Drivetrain

    Science.gov (United States)

    Xie, Zhongzhi

    Hybrid cars as a solution to energy saving, emission reduction measures, have received widespread attention. Motor drive system as an important part of the hybrid vehicles as an important object of study. Based on the hybrid electric vehicle powertrain control system for permanent magnet synchronous motor as the object of study. Can be applied to hybrid car compares the characteristics of traction motors, chose permanent magnet synchronous Motors as drive motors for hybrid vehicles. Building applications in hybrid cars in MATLAB/Simulink simulation model of permanent-magnet synchronous motor speed control system and analysis of simulation results.

  2. New hybrid systems

    International Nuclear Information System (INIS)

    Bernardin, B.

    2001-01-01

    New hybrid systems are made up of a subcritical core, a spallation target and a proton accelerator. The neutrons that are produced in the target by the flux of protons are necessary to maintain the chain reaction of fission. Some parameters that are important for a classical nuclear reactor like doppler coefficient or delayed neutron fraction do not matter in a hybrid system. In a PWR-type reactor or in a fast reactor the concentration of actinides has a bad impact on these 2 parameters, so it is justified to study hybrid systems as actinide transmuters. The hybrid system, because of its external source of neutrons can put aside an important reactivity margin. This reactivity margin can be used to design safer nuclear reactors (particularly in some situations of reactivity accidents) or to irradiate fuel elements containing high concentrations of minor actinides that could not be allowed in a classical reactor. This article reviews various ways of integrating hybrid systems in a population of already existing nuclear reactors in order to manage quantities of plutonium, of minor actinides or of long-life fission products. (A.C.)

  3. General Editorial

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education. General Editorial. Articles in Resonance – Journal of Science Education. Volume 19 Issue 1 January 2014 pp 1-2 General Editorial. General Editorial on Publication Ethics · R Ramaswamy · More Details Fulltext PDF. Volume 19 Issue 1 January 2014 pp 3-3 ...

  4. Growth response of Larix hybrids between L. kaempferi and L. gmelinii var. japonica with altitudinal gradient

    Energy Technology Data Exchange (ETDEWEB)

    Kisanuki, Hiromitsu; Kurahashi, Akio; Takahashi, Yasuo [Tokyo Univ. Forest, Hokkaido (Japan)

    1995-12-31

    To test the adaptability of Japanese larch, Dahurian larch and their hybrid to the environment in Hokkaido, these three materials were planted and surveyed of their survival and growth for 30 years at four elevation in central Hokkaido, northern Japan. Japanese larch showed low adaptation with high mortality affected by voles at every elevation. Dahurian larch has high vole resistance but showed high mortality caused by the infection of Armillaria root rot. Hybrid could persist through low to high elevation. Only hybrid showed enough growth at the highest elevation. Stress tolerance of hybrid was confirmed under high altitudinal condition. 12 refs, 4 figs, 3 tabs

  5. Growth response of Larix hybrids between L. kaempferi and L. gmelinii var. japonica with altitudinal gradient

    Energy Technology Data Exchange (ETDEWEB)

    Kisanuki, Hiromitsu; Kurahashi, Akio; Takahashi, Yasuo [Tokyo Univ. Forest, Hokkaido (Japan)

    1996-12-31

    To test the adaptability of Japanese larch, Dahurian larch and their hybrid to the environment in Hokkaido, these three materials were planted and surveyed of their survival and growth for 30 years at four elevation in central Hokkaido, northern Japan. Japanese larch showed low adaptation with high mortality affected by voles at every elevation. Dahurian larch has high vole resistance but showed high mortality caused by the infection of Armillaria root rot. Hybrid could persist through low to high elevation. Only hybrid showed enough growth at the highest elevation. Stress tolerance of hybrid was confirmed under high altitudinal condition. 12 refs, 4 figs, 3 tabs

  6. Occupational Stress

    OpenAIRE

    Löblová, Klára

    2011-01-01

    The thesis deals with load, stress and related questions of the working life. Work-related stress brings numerous difficulties not only to affected individuals, but as a result also to organizations. The thesis follows symptoms, impacts, somatic and mental aspects of stress, its types and also types of stressors, which cause this problem. It is concentrated on workload as a specific area of work-related stress, individual resistance to the load, factors of workload and work-related stress and...

  7. Solar central receiver hybrid power system, Phase I. Volume 3. Appendices. Final technical report, October 1978-August 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-01

    A design study for a central receiver/fossil fuel hybrid power system using molten salts for heat transfer and heat storage is presented. This volume contains the appendices: (A) parametric salt piping data; (B) sample heat exchanger calculations; (C) salt chemistry and salt/materials compatibility evaluation; (D) heliostat field coordinates; (E) data lists; (F) STEAEC program input data; (G) hybrid receiver design drawings; (H) hybrid receiver absorber tube thermal math model; (I) piping stress analysis; (J) 100-MWe 18-hour storage solar central receiver hybrid power system capital cost worksheets; and (K) 500-MWe 18-hour solar central receiver hybrid power system cost breakdown. (WHK)

  8. The Hybrid Museum: Hybrid Economies of Meaning

    DEFF Research Database (Denmark)

    Vestergaard, Vitus

    2013-01-01

    Social media has created new ways of communicating and has brought about a new distinctive ethos. New literacies are not simply about new technology but also about this new ethos. Many museums are embracing this ethos by what is often called participatory practices. From a sociocultural perspective...... this article shows that there are two different museum mindsets where the second mindset leans towards participatory practices. It is shown how a museum can support a hybrid economy of meaning that builds on both a user generated economy of meaning and an institutional economy of meaning and adds value to both...

  9. The α-Amino Group of the Threonine Substrate As The General Base During tRNA Aminoacylation: A New Version of Substrate Assisted Catalysis Predicted by Hybrid DFT

    Science.gov (United States)

    Huang, WenJuan; Bushnell, Eric A. C.; Francklyn, Christopher S.; Gauld, James W.

    2013-01-01

    Density functional theory-based methods in combination with large chemical models have been used to investigate the mechanism of the second half-reaction catalyzed by Thr-tRNA synthetase; aminoacyl transfer from Thr-AMP onto the A763'OH of the cognate tRNA. In particular, we have examined pathways in which an active site His309 residue is either protonated or neutral (i.e., potentially able to act as a base). In the protonated His309-assisted mechanism, the rate-limiting step is formation of the tetrahedral intermediate. The barrier for this step is 155.0 kJ mol−1 and thus, such a pathway is concluded to not be enzymatically feasible. For the neutral His309-assisted mechanism two models were used with the difference being whether Lys465 was included. For either model the barrier of the rate-limiting step is below the upper-thermodynamic enzymatic limit of ∼125 kJ mol−1. Specifically, without Lys465 the rate-limiting barrier is 122.1 kJ mol−1 and corresponds to a rotation about the tetrahedral intermediates Ccarb—OH bond. For the model with Lys465 the rate-limiting barrier is slightly lower and corresponds to the formation of the tetrahedral intermediate. Importantly, for both neutral His309’ models the neutral amino group of the threonyl substrate directly acts as the proton accepter; in the formation of the tetrahedral intermediate the A763'OH proton is directly transferred onto the Thr-NH2. Therefore, the overall mechanism follows a general substrate assisted catalytic mechanism. PMID:21942566

  10. Hybrid system concepts

    International Nuclear Information System (INIS)

    Landeyro, P.A.

    1995-01-01

    Hybrid systems studied for fissile material production, were reconsidered for minor actinide and long-lived fission product destruction as alternative to the traditional final disposal of nuclear waste. Now there are attempts to extend the use of the concepts developed for minor actinide incineration to plutonium burning. The most promising hybrid system concept considers fuel and target both as liquids. From the results obtained, the possibility to adopt composite targets seems the most promising solution, but still there remains the problem of Pu production, not acceptable in a burning system. This kind of targets can be mainly used for fissile material production, while for accelerator driven burners it is most convenient to use a liquid lead target. The most suitable solvent is heavy water for minor actinide annihilation in the blanket of a hybrid system. Due to the criticality conditions and the necessity of electric energy production, the blanket using plutonium dissolved in molten salts is the most convenient one. (author)

  11. Does hybridization of endophytic symbionts in a native grass increase fitness in resource-limited environments?

    DEFF Research Database (Denmark)

    Faeth, Stanley H.; Oberhofer, Martina; Saari, Susanna Talvikki

    2017-01-01

    to their grass hosts, especially in stressful environments. We tested the hybrid fitness hypothesis (HFH) that hybrid endophytes enhance fitness in stressful environments relative to non-hybrid endophytes. In a long-term field experiment, we monitored growth and reproduction of hybrid-infected (H+), non......-hybrid infected (NH+), naturally endophyte free (E-) plants and those plants from which the endophyte had been experimentally removed (H- and NH-) in resource-rich and resource-poor environments. Infection by both endophyte species enhanced growth and reproduction. H+ plants outperformed NH+ plants in terms...... of growth by the end of the experiment, supporting HFH. However, H+ plants only outperformed NH+ plants in the resource-rich treatment, contrary to HFH. Plant genotypes associated with each endophyte species had strong effects on growth and reproduction. Our results provide some support the HFH hypothesis...

  12. Frontier battery development for hybrid vehicles.

    Science.gov (United States)

    Lewis, Heather; Park, Haram; Paolini, Maion

    2012-04-23

    Interest in hybrid-electric vehicles (HEVs) has recently spiked, partly due to an increasingly negative view toward the U.S. foreign oil dependency and environmental concerns. Though HEVs are becoming more common, they have a significant price premium over gasoline-powered vehicles. One of the primary drivers of this "hybrid premium" is the cost of the vehicles' batteries. This paper focuses on these batteries used in hybrid vehicles, examines the types of batteries used for transportation applications and addresses some of the technological, environmental and political drivers in battery development and the deployment of HEVs. This paper examines the claim, often voiced by HEV proponents, that by taking into account savings on gasoline and vehicle maintenance, hybrid cars are cheaper than traditional gasoline cars. This is done by a quantitative benefit-cost analysis, in addition to qualitative benefit-cost analysis from political, technological and environmental perspectives. The quantitative benefit-cost analysis shows that, taking account of all costs for the life of the vehicle, hybrid cars are in fact more expensive than gasoline-powered vehicles; however, after five years, HEVs will break even with gasoline cars. Our results show that it is likely that after 5 years, using hybrid vehicles should be cheaper in effect and yield a positive net benefit to society. There are a number of externalities that could significantly impact the total social cost of the car. These externalities can be divided into four categories: environmental, industrial, R&D and political. Despite short-term implications and hurdles, increased HEV usage forecasts a generally favorable long-term net benefit to society. Most notably, increasing HEV usage could decrease greenhouse gas emissions, while also decreasing U.S. dependence on foreign oil.

  13. Frontier battery development for hybrid vehicles

    Directory of Open Access Journals (Sweden)

    Lewis Heather

    2012-04-01

    Full Text Available Abstract Background Interest in hybrid-electric vehicles (HEVs has recently spiked, partly due to an increasingly negative view toward the U.S. foreign oil dependency and environmental concerns. Though HEVs are becoming more common, they have a significant price premium over gasoline-powered vehicles. One of the primary drivers of this “hybrid premium” is the cost of the vehicles’ batteries. This paper focuses on these batteries used in hybrid vehicles, examines the types of batteries used for transportation applications and addresses some of the technological, environmental and political drivers in battery development and the deployment of HEVs. Methods This paper examines the claim, often voiced by HEV proponents, that by taking into account savings on gasoline and vehicle maintenance, hybrid cars are cheaper than traditional gasoline cars. This is done by a quantitative benefit-cost analysis, in addition to qualitative benefit-cost analysis from political, technological and environmental perspectives. Results The quantitative benefit-cost analysis shows that, taking account of all costs for the life of the vehicle, hybrid cars are in fact more expensive than gasoline-powered vehicles; however, after five years, HEVs will break even with gasoline cars. Conclusions Our results show that it is likely that after 5 years, using hybrid vehicles should be cheaper in effect and yield a positive net benefit to society. There are a number of externalities that could significantly impact the total social cost of the car. These externalities can be divided into four categories: environmental, industrial, R&D and political. Despite short-term implications and hurdles, increased HEV usage forecasts a generally favorable long-term net benefit to society. Most notably, increasing HEV usage could decrease greenhouse gas emissions, while also decreasing U.S. dependence on foreign oil.

  14. Frontier battery development for hybrid vehicles

    Science.gov (United States)

    2012-01-01

    Background Interest in hybrid-electric vehicles (HEVs) has recently spiked, partly due to an increasingly negative view toward the U.S. foreign oil dependency and environmental concerns. Though HEVs are becoming more common, they have a significant price premium over gasoline-powered vehicles. One of the primary drivers of this “hybrid premium” is the cost of the vehicles’ batteries. This paper focuses on these batteries used in hybrid vehicles, examines the types of batteries used for transportation applications and addresses some of the technological, environmental and political drivers in battery development and the deployment of HEVs. Methods This paper examines the claim, often voiced by HEV proponents, that by taking into account savings on gasoline and vehicle maintenance, hybrid cars are cheaper than traditional gasoline cars. This is done by a quantitative benefit-cost analysis, in addition to qualitative benefit-cost analysis from political, technological and environmental perspectives. Results The quantitative benefit-cost analysis shows that, taking account of all costs for the life of the vehicle, hybrid cars are in fact more expensive than gasoline-powered vehicles; however, after five years, HEVs will break even with gasoline cars. Conclusions Our results show that it is likely that after 5 years, using hybrid vehicles should be cheaper in effect and yield a positive net benefit to society. There are a number of externalities that could significantly impact the total social cost of the car. These externalities can be divided into four categories: environmental, industrial, R&D and political. Despite short-term implications and hurdles, increased HEV usage forecasts a generally favorable long-term net benefit to society. Most notably, increasing HEV usage could decrease greenhouse gas emissions, while also decreasing U.S. dependence on foreign oil. PMID:22540987

  15. The tokamak hybrid reactor

    International Nuclear Information System (INIS)

    Kelly, J.L.; Rose, R.P.

    1981-01-01

    At a time when the potential benefits of various energy options are being seriously evaluated in many countries through-out the world, it is both timely and important to evaluate the practical application of fusion reactors for their economical production of nuclear fissile fuels from fertile fuels. The fusion hybrid reactor represents a concept that could assure the availability of adequate fuel supplies for a proven nuclear technology and have the potential of being an electrical energy source as opposed to an energy consumer as are the present fuel enrichment processes. Westinghouse Fusion Power Systems Department, under Contract No. EG-77-C-02-4544 with the Department of Energy, Office of Fusion Energy, has developed a preliminary conceptual design for an early twenty-first century fusion hybrid reactor called the commercial Tokamak Hybrid Reactor (CTHR). This design was developed as a first generation commercial plant producing fissile fuel to support a significant number of client Light Water Reactor (LWR) Plants. To the depth this study has been performed, no insurmountable technical problems have been identified. The study has provided a basis for reasonable cost estimates of the hybrid plants as well as the hybrid/LWR system busbar electricity costs. This energy system can be optimized to have a net cost of busbar electricity that is equivalent to the conventional LWR plant, yet is not dependent on uranium ore prices or standard enrichment costs, since the fusion hybrid can be fueled by numerous fertile fuel resources. A nearer-term concept is also defined using a beam driven fusion driver in lieu of the longer term ignited operating mode. (orig.)

  16. Stress og hjerte-kar-sygdom

    DEFF Research Database (Denmark)

    Ebstrup, Jeanette Frost; Jørgensen, Torben

    2012-01-01

    and hypothalamic-pituitary-adrenal axis) are also found. Personality and general coping resources influence stress-appraisal, stress-coping and stress-response. Future studies should integrate stress as a cause (stressor), as a subjective reaction (perception), and as a physiological reaction in the same...

  17. Hybride textuelle Strukturen und hybride textuelle Einheiten. Ein ...

    African Journals Online (AJOL)

    carrying set of all hybrid hierarchical structures are element-heterogeneous whilst the structure- carrying set of all ... grams of hierarchical hybrid article structures, the nodes for those text segments that establish the hybrid status of .... der; d ∈ ArtA ⊣ G|WAr (= Artikelangabe, anhand derer das Genus (= G) und zugleich die ...

  18. Hydraulic Hybrid Vehicle Publications | Transportation Research | NREL

    Science.gov (United States)

    Hydraulic Hybrid Vehicle Publications Hydraulic Hybrid Vehicle Publications The following technical papers and fact sheets provide information about NREL's hydraulic hybrid fleet vehicle evaluations . Refuse Trucks Project Startup: Evaluating the Performance of Hydraulic Hybrid Refuse Vehicles. Bob

  19. Near-term hybrid vehicle program, phase 1

    Science.gov (United States)

    1979-01-01

    The preliminary design of a hybrid vehicle which fully meets or exceeds the requirements set forth in the Near Term Hybrid Vehicle Program is documented. Topics addressed include the general layout and styling, the power train specifications with discussion of each major component, vehicle weight and weight breakdown, vehicle performance, measures of energy consumption, and initial cost and ownership cost. Alternative design options considered and their relationship to the design adopted, computer simulation used, and maintenance and reliability considerations are also discussed.

  20. ABOUT HYBRID BIDIRECTIONAL ASSOCIATIVE MEMORY NEURAL NETWORKS WITH DISCRETE DELAYS

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper, hybrid bidirectional associative memory neural networks with discrete delays is considered. By ingeniously importing real parameters di > 0(i = 1,2,···,n) which can be adjusted, we establish some new sufficient conditions for the dynamical characteristics of hybrid bidirectional associative memory neural networks with discrete delays by the method of variation of parameters and some analysis techniques. Our results generalize and improve the related results in [10,11]. Our work is significant...

  1. Genetic complexity underlying hybrid male sterility in Drosophila.

    OpenAIRE

    Sawamura, Kyoichi; Roote, John; Wu, Chung-I; Yamamoto, Masa-Toshi

    2004-01-01

    Recent genetic analyses of closely related species of Drosophila have indicated that hybrid male sterility is the consequence of highly complex synergistic effects among multiple genes, both conspecific and heterospecific. On the contrary, much evidence suggests the presence of major genes causing hybrid female sterility and inviability in the less-related species, D. melanogaster and D. simulans. Does this contrast reflect the genetic distance between species? Or, generally, is the genetic b...

  2. Methodology for the hybrid solution of systems of differential equations

    International Nuclear Information System (INIS)

    Larrinaga, E.F.; Lopez, M.A.

    1993-01-01

    This work shows a general methodology of solution to systems of differential equations in hybrid computers. Taking into account this methodology, a mathematical model was elaborated. It offers wide possibilities of recording and handling the results on the basis of using the hybrid system IBM-VIDAC 1224 which the ISCTN has. It also presents the results gained when simulating a simple model of a nuclear reactor, which was used in the validation of the results of the computational model

  3. Doubts about hybrids

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The natural draught wet cooling tower with a height of 160 m is considerably taller than the 80 m high hybrid cooling tower, but the latter has a considerably larger diameter. Spray losses for both types are about 4.5 kg/sec for a thermal output of 2500 MW. Apart from the pump load, the natural cooling tower requires no power. Apart from higher pump loads, the hybrid cooling tower requires power for the fans. The energy demand for this purpose is 1.5 to 3% of the nett powerstation output. For the Isar 2 nuclear powerstation this would mean a reduction in puput of about 35 MW. (orig.) [de

  4. Analog and hybrid computing

    CERN Document Server

    Hyndman, D E

    2013-01-01

    Analog and Hybrid Computing focuses on the operations of analog and hybrid computers. The book first outlines the history of computing devices that influenced the creation of analog and digital computers. The types of problems to be solved on computers, computing systems, and digital computers are discussed. The text looks at the theory and operation of electronic analog computers, including linear and non-linear computing units and use of analog computers as operational amplifiers. The monograph examines the preparation of problems to be deciphered on computers. Flow diagrams, methods of ampl

  5. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  6. Mirror fusion--fission hybrids

    International Nuclear Information System (INIS)

    Lee, J.D.

    1978-01-01

    The fusion-fission concept and the mirror fusion-fission hybrid program are outlined. Magnetic mirror fusion drivers and blankets for hybrid reactors are discussed. Results of system analyses are presented and a reference design is described

  7. The BWR Hybrid 4 control rod

    International Nuclear Information System (INIS)

    Gross, H.; Fuchs, H.P.; Lippert, H.J.; Dambietz, W.

    1988-01-01

    The service life of BWR control rods designed in the past has been unsatisfactory. The main reason was irradiation assisted stress corrosion cracking of B 4 C rods caused by external swelling of the B 4 C powder. By this reason KWU developed an improved BWR control rod (Hybrid 4 control rod) with extended service life and increased control rod worth. It also allows the procedure for replacing and rearranging fuel assemblies to be considerably simplified. A complete set of Hydbrid 4 control rods is expected to last throughout the service life of a plant (assumption: ca. 40 years) if an appropriate control rod reshuffling management program is used. (orig.)

  8. The maintenance of hybrids by parasitism in a freshwater snail.

    Science.gov (United States)

    Guttel, Yonathan; Ben-Ami, Frida

    2014-11-01

    Hybrids have often been labelled evolutionary dead-ends due to their lower fertility and viability. However, there is growing awareness that hybridisation between different species may play a constructive role in animal evolution as a means to create variability. Thus, hybridisation and introgression may contribute to adaptive evolution, for example with regards to natural antagonists (parasites, predators, competitors) and adaptation to local environmental conditions. Here we investigated whether parasite intensity contributes to the continuous recreation of hybrids in 74 natural populations of Melanopsis, a complex of freshwater snails with three species. We also examined, under laboratory conditions, whether hybrids and their parental taxa differ in their tolerance of low and high temperatures and salinity levels. Infections were consistently less prevalent in males than in females, and lower in snails from deeper habitats. Infection prevalence in hybrids was significantly lower than in the parental taxa. Low hybrid infection rates could not be explained by sediment type, snail density or geographic distribution of the sampling sites. Interestingly, infected hybrid snails did not show signs of parasite-induced gigantism, whereas all parental taxa did. We found that hybrids mostly coped with extreme temperatures and salinity levels as well as their parental taxa did. Taken together, our results suggest that Melanopsis hybrids perform better in the presence of parasites and environmental stress. This may explain the widespread and long-term occurrence of Melanopsis hybrids as evidenced by paleontological and biogeographic data. Hybridisation may be an adaptive host strategy, reducing infection rates and resisting gigantism. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  9. Changes in rRNA levels during stress invalidates results from mRNA blotting: Fluorescence in situ rRNA hybridization permits renormalization for estimation of cellular mRNA levels

    DEFF Research Database (Denmark)

    Hansen, M.C.; Nielsen, A.K.; Molin, Søren

    2001-01-01

    obtained by these techniques are compared between experiments in which differences in growth rates, strains, or stress treatments occur, the normalization procedure may have a significant impact on the results. In this report we present a solution to the normalization problem in RNA slot blotting...... the relative level of rRNA per cell, and slot blotting to rRNA probes, which estimates the level of rRNA per extracted total RNA, the amount of RNA per cell was calculated in a series of heat shock experiments with the gram-positive bacterium Lactococcus lactis. It was found that the level of rRNA per cell...... decreased to 30% in the course of the heat shock. This lowered ribosome level led to a decrease in the total RNA content, resulting in a gradually increasing overestimation of the mRNA levels throughout the experiment. Using renormalized cellular mRNA levels, the HrcA-mediated regulation of the genes...

  10. Security in hybrid cloud computing

    OpenAIRE

    Koudelka, Ondřej

    2016-01-01

    This bachelor thesis deals with the area of hybrid cloud computing, specifically with its security. The major aim of the thesis is to analyze and compare the chosen hybrid cloud providers. For the minor aim this thesis compares the security challenges of hybrid cloud as opponent to other deployment models. In order to accomplish said aims, this thesis defines the terms cloud computing and hybrid cloud computing in its theoretical part. Furthermore the security challenges for cloud computing a...

  11. Hybrid Ventilation Air Flow Process

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols

    The scope of this annex is therefore to obtain better knowledge of the use of hybrid ventilation technologies. The annex focus on development of control strategies for hybrid ventilation, on development of methods to predict hybrid ventilation performance in office buildings and on implementation...

  12. Forces in general relativity

    International Nuclear Information System (INIS)

    Ridgely, Charles T

    2010-01-01

    Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced by an observer in general coordinates. The general force is then applied to the local co-moving coordinate system of a uniformly accelerating observer, leading to an expression of the inertial force experienced by the observer. Next, applying the general force in Schwarzschild coordinates is shown to lead to familiar expressions of the gravitational force. As a more complex demonstration, the general force is applied to an observer in Boyer-Lindquist coordinates near a rotating, Kerr black hole. It is then shown that when the angular momentum of the black hole goes to zero, the force on the observer reduces to the force on an observer held stationary in Schwarzschild coordinates. As a final consideration, the force on an observer moving in rotating coordinates is derived. Expressing the force in terms of Christoffel symbols in rotating coordinates leads to familiar expressions of the centrifugal and Coriolis forces on the observer. It is envisioned that the techniques presented herein will be most useful to graduate level students, as well as those undergraduate students having experience with general relativity and tensor analysis.

  13. Development and application of an antibody-based protein microarray to assess physiological stress in grizzly bears (Ursus arctos).

    Science.gov (United States)

    Carlson, Ruth I; Cattet, Marc R L; Sarauer, Bryan L; Nielsen, Scott E; Boulanger, John; Stenhouse, Gordon B; Janz, David M

    2016-01-01

    A novel antibody-based protein microarray was developed that simultaneously determines expression of 31 stress-associated proteins in skin samples collected from free-ranging grizzly bears (Ursus arctos) in Alberta, Canada. The microarray determines proteins belonging to four broad functional categories associated with stress physiology: hypothalamic-pituitary-adrenal axis proteins, apoptosis/cell cycle proteins, cellular stress/proteotoxicity proteins and oxidative stress/inflammation proteins. Small skin samples (50-100 mg) were collected from captured bears using biopsy punches. Proteins were isolated and labelled with fluorescent dyes, with labelled protein homogenates loaded onto microarrays to hybridize with antibodies. Relative protein expression was determined by comparison with a pooled standard skin sample. The assay was sensitive, requiring 80 µg of protein per sample to be run in triplicate on the microarray. Intra-array and inter-array coefficients of variation for individual proteins were generally bears. This suggests that remotely delivered biopsy darts could be used in future sampling. Using generalized linear mixed models, certain proteins within each functional category demonstrated altered expression with respect to differences in year, season, geographical sampling location within Alberta and bear biological parameters, suggesting that these general variables may influence expression of specific proteins in the microarray. Our goal is to apply the protein microarray as a conservation physiology tool that can detect, evaluate and monitor physiological stress in grizzly bears and other species at risk over time in response to environmental change.

  14. Relative biocompatibility of micro-hybrid and nano-hybrid light-activated composite resins.

    Science.gov (United States)

    Olabisi Arigbede, Abiodun; Folasade Adeyemi, Bukola; Femi-Akinlosotu, Omowumi

    2017-01-01

    Background. In vitro studies have revealed a direct association between resin content and cytotoxicity of composite resins; however, implantation studies in this regard are sparse. This study investigates the relationship between filler content of composite resins and biocompatibility. Methods. This research employed twelve 180‒200-gr male Wistar rats, 1 nano-hybrid (Prime-Dent Inc.) and 1 micro-hybrid (Medental Inc.) composite resins containing 74% and 80‒90% filler content, respectively. The samples were assessed on the 2nd, 14th and 90th day of implantation. Four rats were allocated to each day in this experimental study. A section of 1.5mm long cured nano-hybrid and micro-hybrid materials were implanted into the right and left upper and lower limbs of the rats, respectively. Eight samples were generated on each day of observation. Inflammation was graded according to the criteria suggested by Orstavik and Major. Pearson's chi-squared test was employed to determine the relationship between the tissue responses of the two materials. Statistical significance was set at P resin had a score of 3.0 for cellular inflammation. On the 14th day, the micro-hybrid resin also exhibited a lower average grade for cellular inflammation. On the 90th day, the micro-hybrid resin had a higher grade of inflammation (0.9) compared to 0.3 recorded for nano-hybrid. The composite resins with higher filler content elicited a significantly lower grade of inflammation irrespective of the duration (χ=20.000, df=8, P=0.010) while the composite resins with lower filler content elicited a significantly lower inflammatory response on the 90th day (χ=4.000, df=1, P=0.046). Conclusion. The composite resins with higher filler content generally elicited significantly lower grades of inflammation, and the composite resins with lower filler content exhibited significantly lower inflammatory response on the 90th day of implantation.

  15. A generalized model via random walks for information filtering

    International Nuclear Information System (INIS)

    Ren, Zhuo-Ming; Kong, Yixiu; Shang, Ming-Sheng; Zhang, Yi-Cheng

    2016-01-01

    There could exist a simple general mechanism lurking beneath collaborative filtering and interdisciplinary physics approaches which have been successfully applied to online E-commerce platforms. Motivated by this idea, we propose a generalized model employing the dynamics of the random walk in the bipartite networks. Taking into account the degree information, the proposed generalized model could deduce the collaborative filtering, interdisciplinary physics approaches and even the enormous expansion of them. Furthermore, we analyze the generalized model with single and hybrid of degree information on the process of random walk in bipartite networks, and propose a possible strategy by using the hybrid degree information for different popular objects to toward promising precision of the recommendation. - Highlights: • We propose a generalized recommendation model employing the random walk dynamics. • The proposed model with single and hybrid of degree information is analyzed. • A strategy with the hybrid degree information improves precision of recommendation.

  16. A generalized model via random walks for information filtering

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhuo-Ming, E-mail: zhuomingren@gmail.com [Department of Physics, University of Fribourg, Chemin du Musée 3, CH-1700, Fribourg (Switzerland); Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, ChongQing, 400714 (China); Kong, Yixiu [Department of Physics, University of Fribourg, Chemin du Musée 3, CH-1700, Fribourg (Switzerland); Shang, Ming-Sheng, E-mail: msshang@cigit.ac.cn [Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, ChongQing, 400714 (China); Zhang, Yi-Cheng [Department of Physics, University of Fribourg, Chemin du Musée 3, CH-1700, Fribourg (Switzerland)

    2016-08-06

    There could exist a simple general mechanism lurking beneath collaborative filtering and interdisciplinary physics approaches which have been successfully applied to online E-commerce platforms. Motivated by this idea, we propose a generalized model employing the dynamics of the random walk in the bipartite networks. Taking into account the degree information, the proposed generalized model could deduce the collaborative filtering, interdisciplinary physics approaches and even the enormous expansion of them. Furthermore, we analyze the generalized model with single and hybrid of degree information on the process of random walk in bipartite networks, and propose a possible strategy by using the hybrid degree information for different popular objects to toward promising precision of the recommendation. - Highlights: • We propose a generalized recommendation model employing the random walk dynamics. • The proposed model with single and hybrid of degree information is analyzed. • A strategy with the hybrid degree information improves precision of recommendation.

  17. Teelt van hybride wintertarwerassen

    NARCIS (Netherlands)

    Timmer, R.D.; Paauw, J.G.M.

    2003-01-01

    Om de mogelijkheden van de teelt van hybride wintertarwerassen onder Nederlandse omstandigheden in beeld te brengen zijn er van 2000-2002 proeven uitgevoerd op het PPO-proefbedrijf te Lelystad. In deze proeven zijn een 4-tal hybriderassen (Hybnos, Hyno-braba, Hyno-esta, Mercury) vergeleken met een

  18. Hybrid FSAE Vehicle Realization

    Science.gov (United States)

    2010-12-01

    The goal of this multi-year project is to create a fully functional University of Idaho entry in the hybrid FSAE competition. Vehicle integration is underway as part of a variety of 2010-11 senior design projects. This leverages a variety of analytic...

  19. Electric and hybrid vehicles

    Science.gov (United States)

    1979-01-01

    Report characterizes state-of-the-art electric and hybrid (combined electric and heat engine) vehicles. Performance data for representative number of these vehicles were obtained from track and dynamometer tests. User experience information was obtained from fleet operators and individual owners of electric vehicles. Data on performance and physical characteristics of large number of vehicles were obtained from manufacturers and available literature.

  20. Nuclear hybrid energy infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Vivek; Tawfik, Magdy S.

    2015-02-01

    The nuclear hybrid energy concept is becoming a reality for the US energy infrastructure where combinations of the various potential energy sources (nuclear, wind, solar, biomass, and so on) are integrated in a hybrid energy system. This paper focuses on challenges facing a hybrid system with a Small Modular Reactor at its core. The core of the paper will discuss efforts required to develop supervisory control center that collects data, supports decision-making, and serves as an information hub for supervisory control center. Such a center will also be a model for integrating future technologies and controls. In addition, advanced operations research, thermal cycle analysis, energy conversion analysis, control engineering, and human factors engineering will be part of the supervisory control center. Nuclear hybrid energy infrastructure would allow operators to optimize the cost of energy production by providing appropriate means of integrating different energy sources. The data needs to be stored, processed, analyzed, trended, and projected at right time to right operator to integrate different energy sources.

  1. Hybridization of biomedical circuitry

    Science.gov (United States)

    Rinard, G. A.

    1978-01-01

    The design and fabrication of low power hybrid circuits to perform vital signs monitoring are reported. The circuits consist of: (1) clock; (2) ECG amplifier and cardiotachometer signal conditioner; (3) impedance pneumobraph and respiration rate processor; (4) hear/breath rate processor; (5) temperature monitor; and (6) LCD display.

  2. Glueballs, Hybrids and Exotics

    Science.gov (United States)

    Reyes, M. A.; Moreno, G.

    2006-09-01

    We comment on the physics analysis carried out by the Experimental High Energy Physics (EHEP) group of the Instituto de Fisica of the University of Guanajuato (IFUG), Mexico. In particular, this group has been involved in analysis carried out to search for glueball, hybrid and exotic candidates.

  3. Hybrid wars’ information component

    Directory of Open Access Journals (Sweden)

    T. A. Nevskaya

    2015-01-01

    Full Text Available The war of the new generation - hybrid war, the information component which is directed not so much on the direct destruction of the enemy, how to achieve the goals without warfare. Fighting in the information field is no less important than immediate military action.

  4. Glueballs, Hybrids and Exotics

    International Nuclear Information System (INIS)

    Reyes, M. A.; Moreno, G.

    2006-01-01

    We comment on the physics analysis carried out by the Experimental High Energy Physics (EHEP) group of the Instituto de Fisica of the University of Guanajuato (IFUG), Mexico. In particular, this group has been involved in analysis carried out to search for glueball, hybrid and exotic candidates

  5. Hybrid quantum computation

    International Nuclear Information System (INIS)

    Sehrawat, Arun; Englert, Berthold-Georg; Zemann, Daniel

    2011-01-01

    We present a hybrid model of the unitary-evolution-based quantum computation model and the measurement-based quantum computation model. In the hybrid model, part of a quantum circuit is simulated by unitary evolution and the rest by measurements on star graph states, thereby combining the advantages of the two standard quantum computation models. In the hybrid model, a complicated unitary gate under simulation is decomposed in terms of a sequence of single-qubit operations, the controlled-z gates, and multiqubit rotations around the z axis. Every single-qubit and the controlled-z gate are realized by a respective unitary evolution, and every multiqubit rotation is executed by a single measurement on a required star graph state. The classical information processing in our model requires only an information flow vector and propagation matrices. We provide the implementation of multicontrol gates in the hybrid model. They are very useful for implementing Grover's search algorithm, which is studied as an illustrative example.

  6. Prediction of life stress on athletes' burnout: the dual role of perceived stress.

    Science.gov (United States)

    Chyi, Theresa; Lu, Frank Jing-Horng; Wang, Erica T W; Hsu, Ya-Wen; Chang, Ko-Hsin

    2018-01-01

    Although many studies adopted Smith's (1986) cognitive-affective model of athletic burnout in examining stress-burnout relationship, very few studies examined the mediating/moderating role of perceived stress on the stress-burnout relationship. We sampled 195 college student-athletes and assessed their life stress, perceived stress, and burnout. Correlation analyses found all study variables correlated. Two separate hierarchical regression analyses found that the "distress" component of perceived stress mediated athletes' two types of life stress-burnout relationship but "counter-stress" component of perceived stress-moderated athletes' general-life stress-burnout relationship. We concluded that interweaving relationships among athletes' life stress, perceived stress, and burnout are not straightforward. Future research should consider the nature of athletes life stress, and dual role of perceived stress in examining its' association with related psychological responses in athletic settings.

  7. Hybrid keyword search auctions

    KAUST Repository

    Goel, Ashish; Munagala, Kamesh

    2009-01-01

    Search auctions have become a dominant source of revenue generation on the Internet. Such auctions have typically used per-click bidding and pricing. We propose the use of hybrid auctions where an advertiser can make a per-impression as well as a per-click bid, and the auctioneer then chooses one of the two as the pricing mechanism. We assume that the advertiser and the auctioneer both have separate beliefs (called priors) on the click-probability of an advertisement. We first prove that the hybrid auction is truthful, assuming that the advertisers are risk-neutral. We then show that this auction is superior to the existing per-click auction in multiple ways: 1. We show that risk-seeking advertisers will choose only a per-impression bid whereas risk-averse advertisers will choose only a per-click bid, and argue that both kind of advertisers arise naturally. Hence, the ability to bid in a hybrid fashion is important to account for the risk characteristics of the advertisers. 2. For obscure keywords, the auctioneer is unlikely to have a very sharp prior on the click-probabilities. In such situations, we show that having the extra information from the advertisers in the form of a per-impression bid can result in significantly higher revenue. 3. An advertiser who believes that its click-probability is much higher than the auctioneer's estimate can use per-impression bids to correct the auctioneer's prior without incurring any extra cost. 4. The hybrid auction can allow the advertiser and auctioneer to implement complex dynamic programming strategies to deal with the uncertainty in the click-probability using the same basic auction. The per-click and per-impression bidding schemes can only be used to implement two extreme cases of these strategies. As Internet commerce matures, we need more sophisticated pricing models to exploit all the information held by each of the participants. We believe that hybrid auctions could be an important step in this direction. The hybrid

  8. Hybrid keyword search auctions

    KAUST Repository

    Goel, Ashish

    2009-01-01

    Search auctions have become a dominant source of revenue generation on the Internet. Such auctions have typically used per-click bidding and pricing. We propose the use of hybrid auctions where an advertiser can make a per-impression as well as a per-click bid, and the auctioneer then chooses one of the two as the pricing mechanism. We assume that the advertiser and the auctioneer both have separate beliefs (called priors) on the click-probability of an advertisement. We first prove that the hybrid auction is truthful, assuming that the advertisers are risk-neutral. We then show that this auction is superior to the existing per-click auction in multiple ways: 1. We show that risk-seeking advertisers will choose only a per-impression bid whereas risk-averse advertisers will choose only a per-click bid, and argue that both kind of advertisers arise naturally. Hence, the ability to bid in a hybrid fashion is important to account for the risk characteristics of the advertisers. 2. For obscure keywords, the auctioneer is unlikely to have a very sharp prior on the click-probabilities. In such situations, we show that having the extra information from the advertisers in the form of a per-impression bid can result in significantly higher revenue. 3. An advertiser who believes that its click-probability is much higher than the auctioneer\\'s estimate can use per-impression bids to correct the auctioneer\\'s prior without incurring any extra cost. 4. The hybrid auction can allow the advertiser and auctioneer to implement complex dynamic programming strategies to deal with the uncertainty in the click-probability using the same basic auction. The per-click and per-impression bidding schemes can only be used to implement two extreme cases of these strategies. As Internet commerce matures, we need more sophisticated pricing models to exploit all the information held by each of the participants. We believe that hybrid auctions could be an important step in this direction. The

  9. Hybrid inflation in the complex plane

    International Nuclear Information System (INIS)

    Buchmueller, W.; Domcke, V.; Kamada, K.; Schmitz, K.

    2014-04-01

    Supersymmetric hybrid inflation is an exquisite framework to connect inflationary cosmology to particle physics at the scale of grand unification. Ending in a phase transition associated with spontaneous symmetry breaking, it can naturally explain the generation of entropy, matter and dark matter. Coupling F-term hybrid inflation to soft supersymmetry breaking distorts the rotational invariance in the complex inflaton plane - an important fact, which has been neglected in all previous studies. Based on the δN formalism, we analyze the cosmological perturbations for the first time in the full two-field model, also taking into account the fast-roll dynamics at and after the end of inflation. As a consequence of the two-field nature of hybrid inflation, the predictions for the primordial fluctuations depend not only on the parameters of the Lagrangian, but are eventually fixed by the choice of the inflationary trajectory. Recognizing hybrid inflation as a two-field model resolves two shortcomings often times attributed to it: The fine-tuning problem of the initial conditions is greatly relaxed and a spectral index in accordance with the PLANCK data can be achieved in a large part of the parameter space without the aid of supergravity corrections. Our analysis can be easily generalized to other (including large-field) scenarios of inflation in which soft supersymmetry breaking transforms an initially single-field model into a multi-field model.

  10. Cold Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH COLD STRESS Recommend on Facebook Tweet Share Compartir Workers who ... cold environments may be at risk of cold stress. Extreme cold weather is a dangerous situation that ...

  11. Heat Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH HEAT STRESS Recommend on Facebook Tweet Share Compartir OSHA-NIOSH ... hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational ...

  12. Hybrid Wound Filaments for Greater Resistance to Impacts

    Science.gov (United States)

    DeLay, Thomas K.; Patterson, James E.; Olson, Michael A.

    2008-01-01

    A hybrid material containing wound filaments made of a hybrid of high-strength carbon fibers and poly(phenylene benzobisoxazole) [PBO] fibers is discussed. This hybrid material is chosen in an effort to increase the ability of the pressure vessel to resist damage by low-speed impacts (e.g., dropping of tools on the vessel or bumping of the vessel against hard objects during installation and use) without significantly increasing the weight of the vessel. While the basic concept of hybridizing fibers in filament-wound structures is not new, the use of hybridization to increase resistance to impacts is an innovation, and can be expected to be of interest in the composite-pressure-vessel industry. The precise types and the proportions of the high-strength carbon fibers and the PBO fibers in the hybrid are chosen, along with the filament-winding pattern, to maximize the advantageous effects and minimize the disadvantageous effects of each material. In particular, one seeks to (1) take advantage of the ability of the carbon fibers to resist stress rupture while minimizing their contribution to vulnerability of the vessel to impact damage and (2) take advantage of the toughness of the PBO fibers while minimizing their contribution to vulnerability of the vessel to stress rupture. Experiments on prototype vessels fabricated according to this concept have shown promising results. At the time of reporting the information for this article, research toward understanding and optimizing the performances of PBO fibers so as to minimize their contribution to vulnerability of the pressure vessel to stress rupture had yet to be performed.

  13. A hybrid deterministic-probabilistic approach to model the mechanical response of helically arranged hierarchical strands

    Science.gov (United States)

    Fraldi, M.; Perrella, G.; Ciervo, M.; Bosia, F.; Pugno, N. M.

    2017-09-01

    Very recently, a Weibull-based probabilistic strategy has been successfully applied to bundles of wires to determine their overall stress-strain behaviour, also capturing previously unpredicted nonlinear and post-elastic features of hierarchical strands. This approach is based on the so-called "Equal Load Sharing (ELS)" hypothesis by virtue of which, when a wire breaks, the load acting on the strand is homogeneously redistributed among the surviving wires. Despite the overall effectiveness of the method, some discrepancies between theoretical predictions and in silico Finite Element-based simulations or experimental findings might arise when more complex structures are analysed, e.g. helically arranged bundles. To overcome these limitations, an enhanced hybrid approach is proposed in which the probability of rupture is combined with a deterministic mechanical model of a strand constituted by helically-arranged and hierarchically-organized wires. The analytical model is validated comparing its predictions with both Finite Element simulations and experimental tests. The results show that generalized stress-strain responses - incorporating tension/torsion coupling - are naturally found and, once one or more elements break, the competition between geometry and mechanics of the strand microstructure, i.e. the different cross sections and helical angles of the wires in the different hierarchical levels of the strand, determines the no longer homogeneous stress redistribution among the surviving wires whose fate is hence governed by a "Hierarchical Load Sharing" criterion.

  14. Simultaneous thermal analysis and thermodilatometry of hybrid fiber reinforced UHPC

    Science.gov (United States)

    Scheinherrová, Lenka; Fořt, Jan; Pavlík, Zbyšek; Černý, Robert

    2017-07-01

    Development of concrete technology and the availability of variety of materials such as silica fume, mineral microfillers and high-range water-reducing admixtures make possible to produce Ultra-High Performance Concrete (UHPC) with compressive strength higher than 160 MPa. However, UHPC is prone to spall under high temperatures what limits its use for special applications only, such as offshore and marine structures, industrial floors, security barriers etc. The spalling is caused by the thermal stresses due to the temperature gradient during heating, and by the splitting force owing to the release of water vapour. Hybrid fibre reinforcement based on combination of steel and polymer fibres is generally accepted by concrete community as a functional solution preventing spalling. In this way, Ultra-High Performance Fibre Reinforced Concrete (UHPFRC) is produced possessing high mechanical strength, durability and resistance to water and salt ingress. Since UHPFRC find use in construction industry in tunnel linings, precast tunnel segments, and high-rise buildings, its behaviour during the high-temperature exposure and its residual parameters are of the particular importance. On this account, Simultaneous Thermal Analysis (STA) and Thermodilatometry Analysis (TDA) were done in the paper to identify the structural and chemical changes in UHPFRC during its high-temperature load. Based on the experimental results, several physical and chemical processes that studied material underwent at high-temperatures were recognized. The obtained data revealed changes in the composition of the studied material and allowed identification of critical temperatures for material damage.

  15. BIOMETRIC ANALYSIS OF THE ARTIFICIAL HYBRIDIZATION BETWEEN Pangasius djambal BLEEKER, 1846 AND Pangasianodon hypophthalmus SAUVAGE, 1878

    Directory of Open Access Journals (Sweden)

    Rudhy Gustiano

    2016-10-01

    Full Text Available It is really important, since the possible use of these pangasiid hybrids in aquaculture faces the problem of potential impact on wild population. Therefore, it is urgently needed to provide quick identification tools in the field. This study investigated morphological characters of Pangasius djambal and Pangasianodon hypophthalmus and their hybrids. A detailed morphological analysis using 32 morphometric measurements and five meristic counts was done on the hybridization of P. djambal and P. hypophthalmus. Morphometric analysis and meristic counts showed that the reciprocal hybrids have intermediate characters except for gill raker number in which lower than that of parental species. In general, the hybrids have tendency to be like P. hypophthalmus rather than P. djambal. The only typical character of P. djambal appeared on hybrids is teeth shape, both vomerine and palatine. It is clearly defined that the true hybrids have seven pelvic fin rays.

  16. Neuromuscular Stress.

    Science.gov (United States)

    White, Timothy P.; Kern, Marialice

    1994-01-01

    Discusses exercise-induced stress that results from motor unit recruitment, the impact of recruitment on selected systemic support systems, and some of the environmental overlays that affect the degree of physiological stress. Adaptations to sustained changes in physical activity and muscle and myotendinous injury induced by stress are examined.…

  17. Stress Fractures

    Science.gov (United States)

    Stress fractures Overview Stress fractures are tiny cracks in a bone. They're caused by repetitive force, often from overuse — such as repeatedly jumping up and down or running long distances. Stress fractures can also arise from normal use of ...

  18. Hybrid fiber reinforcement and crack formation in Cementitious Composite Materials

    DEFF Research Database (Denmark)

    Pereira, E.B.; Fischer, Gregor; Barros, J.A.O.

    2011-01-01

    reinforcement systems. The research described in this paper shows that the multi-scale conception of cracking and the use of hybrid fiber reinforcements do not necessarily result in an improved tensile behavior of the composite. Particular material design requirements may nevertheless justify the use of hybrid......- to the macroscale. In this study, the performance of different fiber reinforced cementitious composites is assessed in terms of their tensile stress-crack opening behavior. The results obtained from this investigation allow a direct quantitative comparison of the behavior obtained from the different fiber...

  19. Design Optimization of Hybrid FRP/RC Bridge

    Science.gov (United States)

    Papapetrou, Vasileios S.; Tamijani, Ali Y.; Brown, Jeff; Kim, Daewon

    2018-04-01

    The hybrid bridge consists of a Reinforced Concrete (RC) slab supported by U-shaped Fiber Reinforced Polymer (FRP) girders. Previous studies on similar hybrid bridges constructed in the United States and Europe seem to substantiate these hybrid designs for lightweight, high strength, and durable highway bridge construction. In the current study, computational and optimization analyses were carried out to investigate six composite material systems consisting of E-glass and carbon fibers. Optimization constraints are determined by stress, deflection and manufacturing requirements. Finite Element Analysis (FEA) and optimization software were utilized, and a framework was developed to run the complete analyses in an automated fashion. Prior to that, FEA validation of previous studies on similar U-shaped FRP girders that were constructed in Poland and Texas is presented. A finer optimization analysis is performed for the case of the Texas hybrid bridge. The optimization outcome of the hybrid FRP/RC bridge shows the appropriate composite material selection and cross-section geometry that satisfies all the applicable Limit States (LS) and, at the same time, results in the lightest design. Critical limit states show that shear stress criteria determine the optimum design for bridge spans less than 15.24 m and deflection criteria controls for longer spans. Increased side wall thickness can reduce maximum observed shear stresses, but leads to a high weight penalty. A taller cross-section and a thicker girder base can efficiently lower the observed deflections and normal stresses. Finally, substantial weight savings can be achieved by the optimization framework if base and side-wall thickness are treated as independent variables.

  20. Stress and High Blood Pressure: What's the Connection?

    Science.gov (United States)

    Stress and high blood pressure: What's the connection? Stress and long-term high blood pressure may not be linked, but taking steps to reduce your stress can improve your general health, including your blood ...