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Sample records for stress els modifies

  1. Safety aspects of genetically modified crops with abiotic stress tolerance

    NARCIS (Netherlands)

    Liang, C.; Prins, T.W.; Wiel, van de C.C.M.; Kok, E.J.

    2014-01-01

    Abiotic stress, such as drought, salinity, and temperature extremes, significantly reduce crop yields. Hence, development of abiotic stress-tolerant crops by modern biotechnology may contribute to global food security. Prior to introducing genetically modified crops with abiotic stress tolerance to

  2. Achieving high aspect ratio wrinkles by modifying material network stress.

    Science.gov (United States)

    Chen, Yu-Cheng; Wang, Yan; McCarthy, Thomas J; Crosby, Alfred J

    2017-06-07

    Wrinkle aspect ratio, or the amplitude divided by the wavelength, is hindered by strain localization transitions when an increasing global compressive stress is applied to synthetic material systems. However, many examples from living organisms show extremely high aspect ratios, such as gut villi and flower petals. We use three experimental approaches to demonstrate that these high aspect ratio structures can be achieved by modifying the network stress in the wrinkle substrate. We modify the wrinkle stress and effectively delay the strain localization transition, such as folding, to larger aspect ratios by using a zero-stress initial wavy substrate, creating a secondary network with post-curing, or using chemical stress relaxation materials. A wrinkle aspect ratio as high as 0.85, almost three times higher than common values of synthetic wrinkles, is achieved, and a quantitative framework is presented to provide understanding the different strategies and predictions for future investigations.

  3. The modified couple stress functionally graded Timoshenko beam formulation

    International Nuclear Information System (INIS)

    Asghari, M.; Rahaeifard, M.; Kahrobaiyan, M.H.; Ahmadian, M.T.

    2011-01-01

    In this paper, a size-dependent formulation is presented for Timoshenko beams made of a functionally graded material (FGM). The formulation is developed on the basis of the modified couple stress theory. The modified couple stress theory is a non-classic continuum theory capable to capture the small-scale size effects in the mechanical behavior of structures. The beam properties are assumed to vary through the thickness of the beam. The governing differential equations of motion are derived for the proposed modified couple-stress FG Timoshenko beam. The generally valid closed-form analytic expressions are obtained for the static response parameters. As case studies, the static and free vibration of the new model are respectively investigated for FG cantilever and FG simply supported beams in which properties are varying according to a power law. The results indicate that modeling beams on the basis of the couple stress theory causes more stiffness than modeling based on the classical continuum theory, such that for beams with small thickness, a significant difference between the results of these two theories is observed.

  4. Cardiovascular reflexes during rest and exercise modified by gravitational stresses

    Science.gov (United States)

    Bonde-petersen, Flemming

    The hypotheses tested were whether variations in central venous pressure via the low pressure baroreceptors would take over or modify the arterial baroreceptor function, and further to which extent local and "whole body" hydrostatic stresses influence blood flow distribution. We investigated total forearm and skin blood flow (venous occlusion plethysmography and 133-Xe clearance) and cardiac output (rebreathing method) among other parameters. Hypo-and hypergravitational stresses were simulated by LBNP, LBPP, water immersion and lowering of the arm. The changes in flow distribution in the arm were ascribed to arterial baroreceptor function and not to low pressure baroreceptor activity. The enhancement of venous return during water immersion increased exercise tolerance during heat stress presumably due both to increased stroke volume and decreased venous pooling. The response to sustained handgrip exercise during LBNP and LBPP was not different from control measurements and the effects explained by arterial baroreceptor function. Application of exercise and local hydrostatic stresses in combination with gravitational stresses represent an interesting model for further study of the mechanisms behind the distribution of cardiac output to the peripheral organs.

  5. Modified stress intensity factor as a crack growth parameter applicable under large scale yielding conditions

    International Nuclear Information System (INIS)

    Yasuoka, Tetsuo; Mizutani, Yoshihiro; Todoroki, Akira

    2014-01-01

    High-temperature water stress corrosion cracking has high tensile stress sensitivity, and its growth rate has been evaluated using the stress intensity factor, which is a linear fracture mechanics parameter. Stress corrosion cracking mainly occurs and propagates around welded metals or heat-affected zones. These regions have complex residual stress distributions and yield strength distributions because of input heat effects. The authors previously reported that the stress intensity factor becomes inapplicable when steep residual stress distributions or yield strength distributions occur along the crack propagation path, because small-scale yielding conditions deviate around those distributions. Here, when the stress intensity factor is modified by considering these distributions, the modified stress intensity factor may be used for crack growth evaluation for large-scale yielding. The authors previously proposed a modified stress intensity factor incorporating the stress distribution or yield strength distribution in front of the crack using the rate of change of stress intensity factor and yield strength. However, the applicable range of modified stress intensity factor for large-scale yielding was not clarified. In this study, the range was analytically investigated by comparison with the J-integral solution. A three-point bending specimen with parallel surface crack was adopted as the analytical model and the stress intensity factor, modified stress intensity factor and equivalent stress intensity factor derived from the J-integral were calculated and compared under large-scale yielding conditions. The modified stress intensity was closer to the equivalent stress intensity factor when compared with the stress intensity factor. If deviation from the J-integral solution is acceptable up to 2%, the modified stress intensity factor is applicable up to 30% of the J-integral limit, while the stress intensity factor is applicable up to 10%. These results showed that

  6. Intensity of anxiety is modified via complex integrative stress circuitries.

    Science.gov (United States)

    Smith, Justin P; Prince, Melissa A; Achua, Justin K; Robertson, James M; Anderson, Raymond T; Ronan, Patrick J; Summers, Cliff H

    2016-01-01

    Escalation of anxious behavior while environmentally and socially relevant contextual events amplify the intensity of emotional response produces a testable gradient of anxiety shaped by integrative circuitries. Apprehension of the Stress-Alternatives Model apparatus (SAM) oval open field (OF) is measured by the active latency to escape, and is delayed by unfamiliarity with the passageway. Familiar OF escape is the least anxious behavior along the continuum, which can be reduced by anxiolytics such as icv neuropeptide S (NPS). Social aggression increases anxiousness in the SAM, reducing the number of mice willing to escape by 50%. The apprehension accompanying escape during social aggression is diminished by anxiolytics, such as exercise and corticotropin releasing-factor receptor 1 (CRF1) antagonism, but exacerbated by anxiogenic treatment, like antagonism of α2-adrenoreceptors. What is more, the anxiolytic CRF1 and anxiogenic α2-adrenoreceptor antagonists also modify behavioral phenotypes, with CRF1 antagonism allowing escape by previously submissive animals, and α2-adrenoreceptor antagonism hindering escape in mice that previously engaged in it. Gene expression of NPS and brain-derived neurotrophic factor (BDNF) in the central amygdala (CeA), as well as corticosterone secretion, increased concomitantly with the escalating anxious content of the mouse-specific anxiety continuum. The general trend of CeA NPS and BDNF expression suggested that NPS production was promoted by increasing anxiousness, and that BDNF synthesis was associated with learning about ever-more anxious conditions. The intensity gradient for anxious behavior resulting from varying contextual conditions may yield an improved conceptualization of the complexity of mechanisms producing the natural continuum of human anxious conditions, and potential therapies that arise therefrom. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Modified variational iteration method for an El Niño Southern Oscillation delayed oscillator

    International Nuclear Information System (INIS)

    Cao Xiao-Qun; Song Jun-Qiang; Zhu Xiao-Qian; Zhang Li-Lun; Zhang Wei-Min; Zhao Jun

    2012-01-01

    This paper studies a delayed air—sea coupled oscillator describing the physical mechanism of El Niño Southern Oscillation. The approximate expansions of the delayed differential equation's solution are obtained successfully by the modified variational iteration method. The numerical results illustrate the effectiveness and correctness of the method by comparing with the exact solution of the reduced model. (general)

  8. Development of stress-modified fracture strain criterion for ductile fracture of API X65 steel

    International Nuclear Information System (INIS)

    Oh, Chang Kyun; Kim, Yun Jae; Park, Jin Moo; Kim, Woo Sik; Baek, Jong Hyun

    2005-01-01

    This paper presents a stress-modified fracture strain for API X65 steel used for gas pipeline, as a function of stress triaxiality. To determine the stress-modified fracture strain, tension test of bars with four different notch radii, made of API X65 steel, is firstly performed, from which true fracture strains are determined as a function of notch radius. Then detailed elastic-plastic, large strain Finite Element (FE) analyses are performed to estimate variations of stress triaxiality in the notched bars with load. Combining experimental with FE results provides the true fracture strain as a function of stress triaxiality, which is regarded as a criterion of ductile fracture. Application of the developed stress-modified fracture strain to failure prediction of gas pipes made of API X65 steel with various types of defects is discussed

  9. RESEARCH OF THE STRESS STATE OF A MODIFIED IN-SITU CONCRETE

    Directory of Open Access Journals (Sweden)

    D. V. Rudenko

    2016-12-01

    Full Text Available Purpose. The article focuses on investigation of the stress state of a modified in-situ concrete of natural hardening. Methodology. To achieve the aim, the research of the microstructure of the modified cement matrix of concrete, as well as the mechanism of structure formation of modified concrete with natural hardening was conducted; the methods for reliable evaluation of concrete strength were defined. Findings. The development of internal stresses affects the properties of concretedifferently. With an increase in temperature-shrinkage deformations in time and, thus, with increasing structural stresses in the cement sheath around the grains of the filler two opposite processes may develop: zone of plastic flow or cracking. Originality. It was established that the structural features complex of the modified concrete when the load transfer leads to the formation of extensive zones of prefracture which is able to absorb a significant amount of elastic strain energy that provides the design deformation properties of the concrete for special purposes. Ideas about the definition of the criteria of cracking modified concrete, hardening under natural conditions had further development. Practical value. The resulting equations allow to solve the problem about the minimum level of structural stress in monolithic concrete in a saturated large placeholder, as well as to assess the influence of structural stresses on the properties of concrete. In normal concrete with a relatively thin cement sheath at temperature-shrinkage deformations, high tangential and low radial tension occur. In vivo, this stress is higher as a result of higher values of Δε(τ, which is not observed in the modified concrete. In the modified concretes only tangential stresses are the greatest danger to structures. The change of shrinkage stress with time is straightforward. The total temperature-shrinkage deformations have a sawtooth graph. For modified concrete the amplitude is 48

  10. An improved water budget for the El Yunque National Forest, Puerto Rico, as determined by the Water Supply Stress Index Model

    Science.gov (United States)

    Liangxia Zhang; Ge Sun; Erika Cohen; Steven McNulty; Peter Caldwell; Suzanne Krieger; Jason Christian; Decheng Zhou; Kai Duan; Keren J. Cepero-Pérez

    2018-01-01

    Quantifying the forest water budget is fundamental to making science-based forest management decisions. This study aimed at developing an improved water budget for the El Yunque National Forest (ENF) in Puerto Rico, one of the wettest forests in the United States. We modified an existing monthly scale water balance model, Water Supply Stress Index (WaSSI), to reflect...

  11. Stress-induced evolution and the biosafety of genetically modified

    Indian Academy of Sciences (India)

    This article is focused on the problems of reduction of the risk associated with the deliberate release of genetically modified microorganisms (GMMs) into the environment. Special attention is given to overview the most probable physiological and genetic processes which could be induced in the released GMMs by adverse ...

  12. Genetically modified plants for salinity stress tolerance (abstract)

    International Nuclear Information System (INIS)

    Sopory, S.K.; Singia-Pareek, S.I.; Kumar, S.; Rajgopal, D.; Aggarwal, P.; Kumar, D.; Reddy, K.M.

    2005-01-01

    Several recent reports have indicated that the area under salinity is on the increase and currently very few genotypes of important crop plants are available for cultivation under these conditions. In this regard, identification of novel stress responsive genes and transgenic approach offers an important strategy to develop salt tolerant plants. Using an efficient PCR-based cDNA subtraction method a large number of genes upregulated under salinity and dehydration stress have been identified also in rice and Pennisetum. Functional analysis of some of these genes is being done using transgenic approach. Earlier, we reported on the role of one of the stress regulated genes, glyoxalse I in conferring salinity tolerance. We now show that by manipulating the expression of both the genes of the glyoxalse pathway, glyoxalse I and II together, the ability of the double transgenic plants to tolerate salinity stress is greatly enhanced as compared to the single transgenic plants harbouring either the glyoxalse I or glyoxalse II. The cDNA for glyoxalse II was cloned from rice and mobilized into pCAMBIA vector having hptII gene as the selection marker. The seedlings of the T1 generation transgenic plants survived better under high salinity compared to the wild type plants; the double transgenics had higher limits of tolerance as compared to the lines transformed with single gene. A similar trend was seen even when plants were grown in pots under glass house conditions and raised to maturity under the continued presence of NaCl. In this, the transgenic plants were able to grow, flower and set seeds. The overexpression of glyoxalse pathway was also found to confer stress tolerance in rice. We have also isolated a gene encoding vacuolar sodium/proton antiporter from Pennisetum and over expressed in Brassica juncea and rice. The transgenic plants were able to tolerate salinity stress. Our work along with many others' indicates the potential of transgenic technology in developing

  13. Reducing composite restoration polymerization shrinkage stress through resin modified glass-ionomer based adhesives.

    Science.gov (United States)

    Naoum, S J; Mutzelburg, P R; Shumack, T G; Thode, Djg; Martin, F E; Ellakwa, A E

    2015-12-01

    The aim of this study was to determine whether employing resin modified glass-ionomer based adhesives can reduce polymerization contraction stress generated at the interface of restorative composite adhesive systems. Five resin based adhesives (G Bond, Optibond-All-in-One, Optibond-Solo, Optibond-XTR and Scotchbond-Universal) and two resin modified glass-ionomer based adhesives (Riva Bond-LC, Fuji Bond-LC) were analysed. Each adhesive was applied to bond restorative composite Filtek-Z250 to opposing acrylic rods secured within a universal testing machine. Stress developed at the interface of each adhesive-restorative composite system (n = 5) was calculated at 5-minute intervals over 6 hours. The resin based adhesive-restorative composite systems (RBA-RCS) demonstrated similar interface stress profiles over 6 hours; initial rapid contraction stress development (0-300 seconds) followed by continued contraction stress development ≤0.02MPa/s (300 seconds - 6 hours). The interface stress profile of the resin modified glass-ionomer based adhesive-restorative composite systems (RMGIBA-RCS) differed substantially to the RBA-RCS in several ways. Firstly, during 0-300 seconds the rate of contraction stress development at the interface of the RMGIBA-RCS was significantly (p adhesives can significantly reduce the magnitude and rate of polymerization contraction stress developed at the interface of adhesive-restorative composite systems. © 2015 Australian Dental Association.

  14. Stress and medicine use for headache: does sense of coherence modify the association?

    Science.gov (United States)

    Koushede, Vibeke; Holstein, Bjørn E; Andersen, Anette; Hansen, Ebba Holme

    2011-10-01

    Medicine use as a strategy for coping with daily stressors is an under-studied issue. Studies show that stress is associated with use of over-the-counter medicine, but the underlying mechanisms are not well understood. The aim of this study was to examine whether sense of coherence (SOC) modifies the association between perceived stress and medicine use for headache. National cross-sectional study in Denmark. men and women aged 25-44 years, n = 990. The survey was conducted by web-based questionnaires and telephone interviews. The outcome measure was medicine use for headache. The independent variable was perceived stress. SOC and gender were investigated as moderators. Social class, headache prevalence and severity, and response method were included as co-variates. Our study showed that SOC modified the association between stress and medicine use for headache (only statistically significant among women). The odds for medicine use among women who felt stressed were 2.30 (1.39-3.79) compared to women who did not feel stressed; among men who felt stressed the equivalent odds were 1.46 (0.80-2.66). In analysis stratified by SOC, the odds for medicine use when stressed were 2.09 (0.71-6.21) among women with high SOC, 2.21 (1.10-4.41) among women with medium SOC and 3.69 (1.09-12.47) among women with low SOC. The equivalent odds for men were 1.29 (0.33-5.04), 1.33 (0.59-3.04) and 2.47 (0.57-10.64), respectively. SOC modifies the association between stress and medicine use especially among women. Individuals with fewer coping resources may be more likely to use medicine beyond indication to treat stress.

  15. Affective stress responses during leisure time: Validity evaluation of a modified version of the Stress-Energy Questionnaire.

    Science.gov (United States)

    Hadžibajramović, Emina; Ahlborg, Gunnar; Håkansson, Carita; Lundgren-Nilsson, Åsa; Grimby-Ekman, Anna

    2015-12-01

    Psychosocial stress at work is one of the most important factors behind increasing sick-leave rates. In addition to work stressors, it is important to account for non-work-related stressors when assessing stress responses. In this study, a modified version of the Stress-Energy Questionnaire (SEQ), the SEQ during leisure time (SEQ-LT) was introduced for assessing the affective stress response during leisure time. The aim of this study was to investigate the internal construct validity of the SEQ-LT. A second aim was to define the cut-off points for the scales, which could indicate high and low levels of leisure-time stress and energy, respectively. Internal construct validity of the SEQ-LT was evaluated using a Rasch analysis. We examined the unidimensionality and other psychometric properties of the scale by the fit to the Rasch model. A criterion-based approach was used for classification into high and low stress/energy levels. The psychometric properties of the stress and energy scales of the SEQ-LT were satisfactory, having accommodated for local dependency. The cut-off point for low stress was proposed to be in the interval between 2.45 and 3.02 on the Rasch metric score; while for high stress, it was between 3.65 and 3.90. The suggested cut-off points for the low and high energy levels were values between 1.73-1.97 and 2.66-3.08, respectively. The stress and energy scale of the SEQ-LT satisfied the measurement criteria defined by the Rasch analysis and it provided a useful tool for non-work-related assessment of stress responses. We provide guidelines on how to interpret the scale values. © 2015 the Nordic Societies of Public Health.

  16. Laser pulse, initial stress and modified Ohm's law in micropolar thermoelasticity with microtemperatures

    Science.gov (United States)

    Othman, Mohamed I. A.; Tantawi, Ramadan S.; Hilal, Mohamed I. M.

    2018-03-01

    The present manuscript studies the effect of the initial stress in micropolar magneto-thermoelasticity with microtemperatures heated by a laser pulse. The modified Ohm's law illustrates the temperature gradient and the charge density effects in the governing equations of the studied problem. The used analytical method was the normal modes. The physical quantities are established numerically and represented graphically.

  17. The stress response to surgery: release mechanisms and the modifying effect of pain relief

    DEFF Research Database (Denmark)

    Kehlet, H

    1989-01-01

    This short review updates information on the release mechanisms of the systemic response to surgical injury and the modifying effect of pain relief. Initiation of the response is primarily due to afferent nerve impulses combined with release of humoral substances (such as prostaglandins, kinins...... in releasing the classical endocrine catabolic response, while humoral factors are important for the hyperthermic response, changes in coagulation and fibrinolysis immunofunction, and capillary permeability. The modifying effect of pain relief on the surgical stress response is dependent upon the technique...... on the stress response. In summary, pain alleviation itself may not necessarily lead to an important modification of the stress response, and a combined approach with inhibition of the neural and humoral release mechanisms is necessary for a pronounced inhibition or prevention of the response to surgical injury....

  18. Stress and medicine use for headache: does sense of coherence modify the association?

    DEFF Research Database (Denmark)

    Koushede, Vibeke Jenny; Holstein, Bjørn E; Andersen, Anette

    2011-01-01

    Medicine use as a strategy for coping with daily stressors is an under-studied issue. Studies show that stress is associated with use of over-the-counter medicine, but the underlying mechanisms are not well understood. The aim of this study was to examine whether sense of coherence (SOC) modifies...... the association between perceived stress and medicine use for headache.......Medicine use as a strategy for coping with daily stressors is an under-studied issue. Studies show that stress is associated with use of over-the-counter medicine, but the underlying mechanisms are not well understood. The aim of this study was to examine whether sense of coherence (SOC) modifies...

  19. Pasireotide treatment does not modify hyperglycemic and corticosterone acute restraint stress responses in rats.

    Science.gov (United States)

    Ribeiro-Oliveira, Antônio; Schweizer, Junia R O L; Amaral, Pedro H S; Bizzi, Mariana F; Silveira, Warley Cezar da; Espirito-Santo, Daniel T A; Zille, Giancarlo; Soares, Beatriz S; Schmid, Herbert A; Yuen, Kevin C J

    2018-04-17

    Pasireotide is a new-generation somatostatin analog that acts through binding to multiple somatostatin receptor subtypes. Studies have shown that pasireotide induces hyperglycemia, reduces glucocorticoid secretion, alters neurotransmission, and potentially affects stress responses typically manifested as hyperglycemia and increased corticosterone secretion. This study specifically aimed to evaluate whether pasireotide treatment modifies glucose and costicosterone secretion in response to acute restraint stress. Male Holtzman rats of 150-200 g were treated with pasireotide (10 µg/kg/day) twice-daily for two weeks or vehicle for the same period. Blood samples were collected at baseline and after 5, 10, 30, and 60 min of restraint stress. The three experimental groups comprised of vehicle + restraint (VEHR), pasireotide + restraint (PASR), and pasireotide + saline (PASNR). Following pasireotide treatment, no significant differences in baseline glucose and corticosterone levels were observed among the three groups. During restraint, hyperglycemia was observed at 10 min (p stressed groups when compared to the non-stressed PASNR group (p stressed groups at 5 min (p stressed PASNR group (p stress responses, thus preserving acute stress regulation.

  20. Immediate effects of modified landing pattern on a probabilistic tibial stress fracture model in runners.

    Science.gov (United States)

    Chen, T L; An, W W; Chan, Z Y S; Au, I P H; Zhang, Z H; Cheung, R T H

    2016-03-01

    Tibial stress fracture is a common injury in runners. This condition has been associated with increased impact loading. Since vertical loading rates are related to the landing pattern, many heelstrike runners attempt to modify their footfalls for a lower risk of tibial stress fracture. Such effect of modified landing pattern remains unknown. This study examined the immediate effects of landing pattern modification on the probability of tibial stress fracture. Fourteen experienced heelstrike runners ran on an instrumented treadmill and they were given augmented feedback for landing pattern switch. We measured their running kinematics and kinetics during different landing patterns. Ankle joint contact force and peak tibial strains were estimated using computational models. We used an established mathematical model to determine the effect of landing pattern on stress fracture probability. Heelstrike runners experienced greater impact loading immediately after landing pattern switch (Ptibial strains and the risk of tibial stress fracture in runners with different landing patterns (P>0.986). Immediate transitioning of the landing pattern in heelstrike runners may not offer timely protection against tibial stress fracture, despite a reduction of impact loading. Long-term effects of landing pattern switch remains unknown. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Stress no trabalho do enfermeiro Estrés en el trabajo del enfermero Stress the nurse's work

    Directory of Open Access Journals (Sweden)

    José Roberto Alves da Costa

    2003-09-01

    Full Text Available Este estudo avaliou o stress associado ao trabalho do enfermeiro no trabalho com o portador de transtorno mental inserido no contexto do hospital psiquiátrico. Trata-se de pesquisa quantitativa, analítica, realizada em sete hospitais psiquiátricos da cidade de Fortaleza, Ceará. Utilizou-se os seguintes instrumentos: dados sociodemográficos para descrição da amostra e um inventário para identificar os sintomas de stress no enfermeiro. A população total abrangeu 48 participantes e a amostra 42, a maioria do sexo feminino, o que corresponde a 92,9% do total. Os resultados mostram que em 62% da amostra não apresentaram stress, 30,9% encontravam-se na fase de Resistência e apenas 7,1% na fase de Exaustão. Não houve associação estatisticamente significativa entre a variável tempo de trabalho com o portador de transtorno mental e sintomas de stress. Portanto, o presente estudo não evidenciou a ocorrência do stress nesses profissionais enfermeiros.Este estudio evaluó el estrés del enfermero asociado al trabajo con el portador de trastorno mental en el contexto del hospital psiquiátrico. Se trata de una investigación cuantitativa, analítica, realizada en siete hospitales psiquiátricos, en la ciudad de Fortaleza, Ceará. Se utilizó los siguientes instrumentos: datos sociodemográficos para la descripción de la muestra y un inventario para identificar los síntomas de stress en el enfermero. La población total abarcó 48, siendo la muestra de 42 participantes, la mayoría del sexo femenino, lo que corresponde al 92,9% del total. Los resultados mostraron que no hubo stress en el 62% de los participantes, el 30,9% se encontró en fase de resistencia y el 7,1% en fase de exhausto. No hubo asociación estadísticamente significativa entre el tiempo de trabajo y los síntomas de stress. Por lo tanto, el presente estudio no evidenció la ocurrencia de stress en los profesionales enfermeros.The aim of this study was to appraise stress

  2. Stress-controlled inelastic behavior of modified 9 Cr-1 Mo steel at elevated temperatures

    International Nuclear Information System (INIS)

    Taguchi, Kosei.

    1989-01-01

    Interest in the ferritic steels of higher chromium concentration has increased recently because of an economical combination of mechanical and corrosion properties at elevated temperatures. A modified 9 Cr-1 Mo ferritic steel, developed in the United States, has been expected as an alternative structural material for fast breeder reactor components, in which Type 304 stainless steel or 2.25 Cr-1 Mo steel is currently used. For application of this material to the structural components, a lot of work has been done to develop evaluation methods for the deformation behavior and strength properties. The authors have studied the inelastic behavior and the creep-fatigue properties of modified 9 Cr-1 Mo steel at elevated temperatures, and proposed a constitutive equation and a creep-fatigue damage equation based on the overstress concept. In this paper, the applicability is discussed of the constitutive equation to stress-controlled inelastic behavior, such as creep strain hardening and stress cycling

  3. Schizophrenia and oxidative stress: glutamate cysteine ligase modifier as a susceptibility gene

    DEFF Research Database (Denmark)

    Tosic, Mirjana; Ott, Jurg; Barral, Sandra

    2006-01-01

    Oxidative stress could be involved in the pathophysiology of schizophrenia, a major psychiatric disorder. Glutathione (GSH), a redox regulator, is decreased in patients' cerebrospinal fluid and prefrontal cortex. The gene of the key GSH-synthesizing enzyme, glutamate cysteine ligase modifier (GCLM......) subunit, is strongly associated with schizophrenia in two case-control studies and in one family study. GCLM gene expression is decreased in patients' fibroblasts. Thus, GSH metabolism dysfunction is proposed as one of the vulnerability factors for schizophrenia....

  4. Schizophrenia and oxidative stress: glutamate cysteine ligase modifier as a susceptibility gene

    DEFF Research Database (Denmark)

    Tosic, Mirjana; Ott, Jurg; Barral, Sandra

    2006-01-01

    Oxidative stress could be involved in the pathophysiology of schizophrenia, a major psychiatric disorder. Glutathione (GSH), a redox regulator, is decreased in patients' cerebrospinal fluid and prefrontal cortex. The gene of the key GSH-synthesizing enzyme, glutamate cysteine ligase modifier (GCL......) subunit, is strongly associated with schizophrenia in two case-control studies and in one family study. GCLM gene expression is decreased in patients' fibroblasts. Thus, GSH metabolism dysfunction is proposed as one of the vulnerability factors for schizophrenia....

  5. Stress and deflection analyses of floating roofs based on a load-modifying method

    International Nuclear Information System (INIS)

    Sun Xiushan; Liu Yinghua; Wang Jianbin; Cen Zhangzhi

    2008-01-01

    This paper proposes a load-modifying method for the stress and deflection analyses of floating roofs used in cylindrical oil storage tanks. The formulations of loads and deformations are derived according to the equilibrium analysis of floating roofs. Based on these formulations, the load-modifying method is developed to conduct a geometrically nonlinear analysis of floating roofs with the finite element (FE) simulation. In the procedure with the load-modifying method, the analysis is carried out through a series of iterative computations until a convergence is achieved within the error tolerance. Numerical examples are given to demonstrate the validity and reliability of the proposed method, which provides an effective and practical numerical solution to the design and analysis of floating roofs

  6. Stress-based fatigue assessment of major component in NPP using modified Green's function approach

    International Nuclear Information System (INIS)

    Ko, Han Ok; Jhung, Myung Jo; Choi, Jae Boong

    2013-01-01

    In this paper, the modified GFA which can consider temperature-dependent material properties is proposed by using a neural network (NN) and weight factor. To verify the modified GFA, thermal stresses by the proposed method are compared with those by FEM. Finally, pros and cons of the new method as well as technical findings from the assessment are discussed to show applicability of them. In this paper, the modified GFA considering temperature-dependent material properties is proposed by using NN and weight factor. To verify the proposed method, thermal stresses by the modified Green's function are compared with those by FEM and the results between two methods show a good agreement. Finally, it is anticipated that more precise fatigue evaluation is performed by using the proposed method. Recently, 434 nuclear reactors are being operated in the world. Among them, about 40% reactors are being operated beyond their design life or will be approaching their life. During the long term operation, various degradation mechanisms are occurred. Fatigue damage caused by alternating operational stresses in terms of temperature or pressure change is the one of important damage mechanisms in the nuclear power plants (NPPs). Although components important to safety were designed to withstand the fatigue damage, cumulative usage factor (CUF) at some locations can exceed the design limit beyond the design life. So, it is necessary to monitor the fatigue damage of major components during the long term operation. Researches on fatigue monitoring system (FMS) have been widely performed. In USA, the FatiguePro was developed by EPRI and was applied to the CE, WEC, B and W and GE type reactors. In Korea, the Kori unit 1 which started commercial operation in 1978 is being operated beyond its design life. At the stage of the license renewal, various plans for degradation mechanisms were established and reviewed. And, in case of fatigue damage, to monitor the fatigue damage of major components

  7. Reliability and validity analysis of modified Nursing Stress Scale for Indian population.

    Science.gov (United States)

    Pathak, Vasundhara; Chakraborty, Tania; Mukhopadhyay, Suman

    2013-01-01

    The original Nursing Stress Scale (NSS) was structurally modified according to results of factorial analysis and a new scale was named as modified nursing stress scale (MNSS). This is the first study to modify and validate NSS for Indian nursing population. Factorial analysis showed different factor loading for two subscales and items were shifted according to their loading to provide a more meaningful structure. After relocation of Items 13, 14, and 15 into first factor, this factor was renamed as "emotional and painful conditions of patients" to provide a more appropriate name to the first factor. Items 24, 25, 26, 27, 28, and 29 were found to be distributed under two different factors; one of these two was renamed as "unpredictable changes" and another retained its original name (i.e., workload). This distribution was also supported by rational analysis. All other items were distributed under factors as in the original scale. Rest of the validity assessment was done with the modified scale. Thus, with minor changes in structure, the scale was found to have better content validity.

  8. Neighborhood food environment role in modifying psychosocial stress-diet relationships.

    Science.gov (United States)

    Zenk, Shannon N; Schulz, Amy J; Izumi, Betty T; Mentz, Graciela; Israel, Barbara A; Lockett, Murlisa

    2013-06-01

    Exposure to highly palatable foods may increase eating in response to stress, but this behavioral response has not been examined in relation to the neighborhood food environment. This study examined whether the neighborhood food environment modified relationships between psychosocial stress and dietary behaviors. Probability-sample survey (n=460) and in-person food environment audit data were used. Dietary behaviors were measured using 17 snack food items and a single eating-out-of-home item. Chronic stress was derived from five subscales; major life events was a count of nine items. The neighborhood food environment was measured as availability of large grocery stores, small grocery stores, and convenience stores, as well as proportion of restaurants that were fast food. Two-level hierarchical regression models were estimated. Snack food intake was positively associated with convenience store availability and negatively associated with large grocery store availability. The measures of chronic stress and major life events were generally not associated with either dietary behavior overall, although Latinos were less likely to eat out at high levels of major life events than African Americans. Stress-neighborhood food environment interactions were not statistically significant. Important questions remain regarding the role of the neighborhood food environment in the stress-diet relationship that warrant further investigation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. On Heat Transfer - Stress Analysis of Modified Brick (Reed Filler) Upon Its Production Stage

    Science.gov (United States)

    Ornam, Kurniati; Kimsan, Masykur; Teguh Prakasa, Cadas; Ode Ngkoimani, La; Santi

    2017-05-01

    This paper aimed to scrutinize how burning process in modified brick’s production impinge on crack as a result of stress differentiation between two consecutive layers of the brick’s element. Diffusion engages in burning process of bricks, hence it generates thermal stress on element for different temperature between layers. This research focused on burning process in traditional production ward. Analytical of nonlinear equation and numerical solution, finite difference, were involved to obtain temperature value in each layer, followed by stress calculation. Based on the results, it can be concluded that crack occurs particularly on boundary area, since difussion tends to yield relatively more different value on it. Therefore, certain strategies, that may decrease this differentiation, are required to minimize number of cracks during brick’s production.

  10. Heat stress differentially modifies ethylene biosynthesis and signaling in pea floral and fruit tissues.

    Science.gov (United States)

    Savada, Raghavendra P; Ozga, Jocelyn A; Jayasinghege, Charitha P A; Waduthanthri, Kosala D; Reinecke, Dennis M

    2017-10-01

    Ethylene biosynthesis is regulated in reproductive tissues in response to heat stress in a manner to optimize resource allocation to pollinated fruits with developing seeds. High temperatures during reproductive development are particularly detrimental to crop fruit/seed production. Ethylene plays vital roles in plant development and abiotic stress responses; however, little is known about ethylene's role in reproductive tissues during development under heat stress. We assessed ethylene biosynthesis and signaling regulation within the reproductive and associated tissues of pea during the developmental phase that sets the stage for fruit-set and seed development under normal and heat-stress conditions. The transcript abundance profiles of PsACS [encode enzymes that convert S-adenosyl-L-methionine to 1-aminocyclopropane-1-carboxylic acid (ACC)] and PsACO (encode enzymes that convert ACC to ethylene), and ethylene evolution were developmentally, environmentally, and tissue-specifically regulated in the floral/fruit/pedicel tissues of pea. Higher transcript abundance of PsACS and PsACO in the ovaries, and PsACO in the pedicels was correlated with higher ethylene evolution and ovary senescence and pedicel abscission in fruits that were not pollinated under control temperature conditions. Under heat-stress conditions, up-regulation of ethylene biosynthesis gene expression in pre-pollinated ovaries was also associated with higher ethylene evolution and lower retention of these fruits. Following successful pollination and ovule fertilization, heat-stress modified PsACS and PsACO transcript profiles in a manner that suppressed ovary ethylene evolution. The normal ethylene burst in the stigma/style and petals following pollination was also suppressed by heat-stress. Transcript abundance profiles of ethylene receptor and signaling-related genes acted as qualitative markers of tissue ethylene signaling events. These data support the hypothesis that ethylene biosynthesis is

  11. Determination of Burst Pressure of API Steel Pipes using Stress Modified Critical Strain Model

    International Nuclear Information System (INIS)

    Alang, N A; Razak, N A; Sulaiman, A S

    2012-01-01

    This paper presents a technique which can be used to determine the burst pressure of defective steel pipes using non-linear finite element (FE) analysis. The technique uses stress modified critical strain (SMCS) failure criterion to study the effect of gouge defects on maximum working pressure of API X65 steel pipes. The procedures in determining the model parameters using 3-D, homogeneous isotropic elastic-plastic material model with large deformation finite element analyses from notched tensile bars were systematically discussed. The relationship between burst pressure and gouge depth was proposed. The burst pressure estimated then was compared to experimental data from the literature for validation showing overall good agreements.

  12. Overexpression of heat shock GroEL stress protein in leptospiral biofilm.

    Science.gov (United States)

    Vinod Kumar, K; Lall, Chandan; Vimal Raj, R; Vedhagiri, K; Kartick, C; Surya, P; Natarajaseenivasan, K; Vijayachari, P

    2017-01-01

    Leptospira is the causative agent of leptospirosis, which is an emerging zoonotic disease. Recent studies on Leptospira have demonstrated biofilm formation on abiotic surfaces. The protein expressed in the biofilm was investigated by using SDS-PAGE and immunoblotting in combination with MALDI-TOF mass spectrometry. The proteins expressed in Leptospira biofilm and planktonic cells was analyzed and compared. Among these proteins, one (60 kDa) was found to overexpress in biofilm as compared to the planktonic cells. MALDI-TOF analysis identified this protein as stress and heat shock chaperone GroEL. Our findings demonstrate that GroEL is associated with Leptospira biofilm. GroEL is conserved, highly immunogenic and a prominent stress response protein in pathogenic Leptospira spp., which may have clinical relevance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Flexoelectric Effect on Vibration of Piezoelectric Microbeams Based on a Modified Couple Stress Theory

    Directory of Open Access Journals (Sweden)

    Xingjia Li

    2017-01-01

    Full Text Available A novel electric Gibbs function was proposed for the piezoelectric microbeams (PMBs by employing a modified couple stress theory. Based on the new Gibbs function and the Euler-Bernoulli beam theory, the governing equations which incorporate the effects of couple stress, flexoelectricity, and piezoelectricity were derived for the mechanics of PMBs. The analysis of the effective bending rigidity shows the effects of size and flexoelectricity can greaten the stiffness of PMBs so that the natural frequency increases significantly compared with the Euler-Bernoulli beam, and then the mechanical and electrical properties of PMBs are enhanced compared to the classical beam. This study can guide the design of microscale piezoelectric/flexoelectric structures which may find potential applications in the microelectromechanical systems (MEMS.

  14. Modified single prolonged stress reduces cocaine self-administration during acquisition regardless of rearing environment.

    Science.gov (United States)

    Hofford, Rebecca S; Prendergast, Mark A; Bardo, Michael T

    2018-02-15

    Until recently, there were few rodent models available to study the interaction of post-traumatic stress disorder (PTSD) and drug taking. Like PTSD, single prolonged stress (SPS) produces hypothalamic-pituitary-adrenal (HPA) axis dysfunction and alters psychostimulant self-administration. Other stressors, such as isolation stress, also alter psychostimulant self-administration. However, it is currently unknown if isolation housing combined with SPS can alter the acquisition or maintenance of cocaine self-administration. The current study applied modified SPS (modSPS; two hours restraint immediately followed by cold swim stress) to rats raised in an isolation condition (Iso), enrichment condition (Enr), or standard condition (Std) to measure changes in cocaine self-administration and HPA markers. Regardless of rearing condition, rats exposed to modSPS had greater corticosterone (CORT) release and reduced cocaine self-administration during initial acquisition compared to non-stressed controls. In addition, during initial acquisition, rats that received both Iso rearing and modSPS showed a more rapid increase in cocaine self-administration across sessions compared to Enr and Std rats exposed to modSPS. Following initial acquisition, a dose response analysis showed that Iso rats were overall most sensitive to changes in cocaine unit dose; however, modSPS had no effect on the cocaine dose response curve. Further, there was no effect of either modSPS or differential rearing on expression of glucocorticoid receptor (GR) in hypothalamus, medial prefrontal cortex, amygdala, or nucleus accumbens. By using modSPS in combination with Iso housing, this study identified unique contributions of each stressor to acquisition of cocaine self-administration. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Vibration Characteristics of Piezoelectric Microbeams Based on the Modified Couple Stress Theory

    Directory of Open Access Journals (Sweden)

    R. Ansari

    2014-01-01

    Full Text Available The vibration behavior of piezoelectric microbeams is studied on the basis of the modified couple stress theory. The governing equations of motion and boundary conditions for the Euler-Bernoulli and Timoshenko beam models are derived using Hamilton’s principle. By the exact solution of the governing equations, an expression for natural frequencies of microbeams with simply supported boundary conditions is obtained. Numerical results for both beam models are presented and the effects of piezoelectricity and length scale parameter are illustrated. It is found that the influences of piezoelectricity and size effects are more prominent when the length of microbeams decreases. A comparison between two beam models also reveals that the Euler-Bernoulli beam model tends to overestimate the natural frequencies of microbeams as compared to its Timoshenko counterpart.

  16. A Modified Split Hopkinson Pressure Bar Approach for Mimicking Dynamic Oscillatory Stress Fluctuations During Earthquake Rupture

    Science.gov (United States)

    Braunagel, M. J.; Griffith, W. A.

    2017-12-01

    Past experimental work has demonstrated that rock failure at high strain rates occurs by fragmentation rather than discrete fracture and is accompanied by a dramatic increase in rock strength. However, these observations are difficult to reconcile with the assertion that pulverized rocks in fault zones are the product of impulsive stresses during the passage of earthquake ruptures, as the distance from the principal slip zones of some pulverized rock is too great to exceed fragmentation transition. One potential explanation to this paradox that has been suggested is that repeated loading over the course of multiple earthquake ruptures may gradually reduce the pulverization threshold, in terms of both strain rate and strength. We propose that oscillatory loading during a single earthquake rupture may further lower these pulverization thresholds, and that traditional dynamic experimental approaches, such as the Split Hopkinson Pressure Bar (SHPB) wherein load is applied as a single, smooth, sinusoidal compressive wave, may not reflect natural loading conditions. To investigate the effects of oscillatory compressive loading expected during earthquake rupture propagation, we develop a controlled cyclic loading model on a SHPB apparatus utilizing two striker bars connected by an elastic spring. Unlike traditional SHPB experiments that utilize a gas gun to fire a projectile bar and generate a single compressive wave on impact with the incident bar, our modified striker bar assembly oscillates while moving down the gun barrel and generates two separate compressive pulses separated by a lag time. By modeling the modified assembly as a mass-spring-mass assembly accelerating due to the force of the released gas, we can predict the compression time of the spring upon impact and therefore the time delay between the generation of the first and second compressive waves. This allows us to predictably control load cycles with durations of only a few hundred microseconds. Initial

  17. Fetal sex modifies effects of prenatal stress exposure and adverse birth outcomes.

    Science.gov (United States)

    Wainstock, Tamar; Shoham-Vardi, Ilana; Glasser, Saralee; Anteby, Eyal; Lerner-Geva, Liat

    2015-01-01

    Prenatal maternal stress is associated with pregnancy complications, poor fetal development and poor birth outcomes. Fetal sex has also been shown to affect the course of pregnancy and its outcomes. The aim of this study was to evaluate whether fetal sex modifies the association between continuous exposure to life-threatening rocket attack alarms and adverse pregnancy outcomes. A retrospective cohort study was conducted in which the exposed group was comprised of 1846 women exposed to rocket-attack alarms before and during pregnancy. The unexposed group, with similar sociodemographic characteristics, delivered during the same period of time at the same medical center, but resided out of rocket-attack range. Multivariable models for each gender separately, controlling for possible confounders, evaluated the risk associated with exposure for preterm births (PTB), low birthweight (LBW), small for gestational age and small head circumference (HC). In both univariable and multivariable analyses exposure status was a significant risk factor in female fetuses only: PTB (adj. OR = 1.43; 1.04-1.96), LBW (adj. OR = 1.41; 1.02-1.95) and HC stress.

  18. Molecular responses of genetically modified maize to abiotic stresses as determined through proteomic and metabolomic analyses.

    Directory of Open Access Journals (Sweden)

    Rafael Fonseca Benevenuto

    Full Text Available Some genetically modified (GM plants have transgenes that confer tolerance to abiotic stressors. Meanwhile, other transgenes may interact with abiotic stressors, causing pleiotropic effects that will affect the plant physiology. Thus, physiological alteration might have an impact on the product safety. However, routine risk assessment (RA analyses do not evaluate the response of GM plants exposed to different environmental conditions. Therefore, we here present a proteome profile of herbicide-tolerant maize, including the levels of phytohormones and related compounds, compared to its near-isogenic non-GM variety under drought and herbicide stresses. Twenty differentially abundant proteins were detected between GM and non-GM hybrids under different water deficiency conditions and herbicide sprays. Pathway enrichment analysis showed that most of these proteins are assigned to energetic/carbohydrate metabolic processes. Among phytohormones and related compounds, different levels of ABA, CA, JA, MeJA and SA were detected in the maize varieties and stress conditions analysed. In pathway and proteome analyses, environment was found to be the major source of variation followed by the genetic transformation factor. Nonetheless, differences were detected in the levels of JA, MeJA and CA and in the abundance of 11 proteins when comparing the GM plant and its non-GM near-isogenic variety under the same environmental conditions. Thus, these findings do support molecular studies in GM plants Risk Assessment analyses.

  19. Moderate summer heat stress does not modify immunological parameters of Holstein dairy cows

    Science.gov (United States)

    Lacetera, Nicola; Bernabucci, Umberto; Ronchi, Bruno; Scalia, Daniela; Nardone, Alessandro

    2002-02-01

    The study was undertaken during spring and summer months in a territory representative of the Mediterranean climate to assess the effects of season on some immunological parameters of dairy cows. Twenty Holstein cows were used. Eleven of those cows gave birth during spring; the remaining nine cows gave birth in summer. The two groups of cows were homogeneous for parity. Values of air temperatures and relative humidity were recorded both during spring and summer, and were utilized to calculate the temperature humidity index (THI). One week before the expected calving, rectal temperatures and respiratory rates of the cows were recorded (1500 hours), and cell-mediated immunity was assessed by measuring the proliferation of mitogen-stimulated peripheral blood mononuclear cells (PBMC). Within 3 h of calving, one colostrum sample was taken from each cow and analysed to determine content of immunoglobulin (Ig) G1, IgG2, IgM and IgA. At 48 h after birth, passive immunization of the calves was assessed by measuring total serum IgG. During summer, daytime (0900-2000 hours) THI values were above the upper critical value of 72 [75.2, (SD 2.6)] indicating conditions that could represent moderate heat stress. That THI values were able to predict heat stress was confirmed by the values of rectal temperatures and respiratory rates, which were higher ( P cows. Results indicated that moderate heat stress due to the hot Mediterranean summer does not modify cell-mediated immunity, the protective value of colostrum and passive immunization of the offspring in dairy cows.

  20. Does methyl jasmonate modify the oxidative stress response in Phaseolus coccineus treated with Cu?

    Science.gov (United States)

    Hanaka, Agnieszka; Wójcik, Małgorzata; Dresler, Sławomir; Mroczek-Zdyrska, Magdalena; Maksymiec, Waldemar

    2016-02-01

    results indicated that MJ was both partially potent in modifying the antioxidative enzymes activity and metabolites accumulation in non-stress and Cu-stress conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. The modified indeterminate couple stress model: Why Yang et al.'s arguments motivating a symmetric couple stress tensor contain a gap and why the couple stress tensor may be chosen symmetric nevertheless

    OpenAIRE

    Münch, Ingo; Neff, Patrizio; Madeo, Angela; Ghiba, Ionel-Dumitrel

    2015-01-01

    We show that the reasoning in favor of a symmetric couple stress tensor in Yang et al.'s introduction of the modified couple stress theory contains a gap, but we present a reasonable physical hypothesis, implying that the couple stress tensor is traceless and may be symmetric anyway. To this aim, the origin of couple stress is discussed on the basis of certain properties of the total stress itself. In contrast to classical continuum mechanics, the balance of linear momentum and the balance of...

  2. Modifying Exposure-Based CBT for Cambodian Refugees with Posttraumatic Stress Disorder

    Science.gov (United States)

    Otto, Michael W.; Hinton, Devon E.

    2009-01-01

    Cambodian refugees represent a severely traumatized population living in the United States. In this paper, we describe the modification of a cognitive-behavior therapy program to facilitate delivery of an exposure-based treatment for posttraumatic stress disorder while addressing some of the challenges brought by differences in language and culture between providers and patients. Our treatment modifications include the use of metaphors and culturally relevant examples to aid the communication of core concepts by interpreters, an emphasis on teaching the “process” of exposure therapy rather than relying on specific exposure practice in the group setting, a focus on interoceptive exposure to allow more effective group practice and to address culturally specific symptom interpretations, attention to the way in which treatment procedures interacted with culturally specific beliefs, and efforts to integrate treatment services within the community. Although data are limited, results to date suggest that this modified treatment was acceptable to patients and offered benefits on the order of large effect sizes. PMID:20072706

  3. Modified African Ngoma Healing Ceremony for Stress Reduction: A Pilot Study.

    Science.gov (United States)

    Vinesett, Ava LaVonne; Whaley, Riitta Rutanen; Woods-Giscombe, Cheryl; Dennis, Paul; Johnson, Medina; Li, Yin; Mounzeo, Pline; Baegne, Mabiba; Wilson, Kenneth H

    2017-10-01

    Indigenous people's ceremonies using rhythm and dance have been used for countless generations throughout the world for healing, conflict resolution, social bonding, and spiritual experience. A previous study reported that a ceremony based on the Central African ngoma tradition was favorably received by a group of Americans. The present trial compared the effects of the modified ngoma ceremony (Ngoma) with those of mindfulness-based stress reduction (MBSR) in a randomized pilot study. Twenty-one women were randomized to either Ngoma or MBSR. Both groups had sessions on a weekly basis for 8 weeks and completed questionnaires at baseline, week 8, and 1 month after the intervention. Participants completed questionnaires, which included self-report of depressive and anxiety symptoms, health status (e.g., quality of life and functioning), social bonding, and perception of the credibility of the two interventions. Both groups showed improvements in depression, anxiety, emotional well being, and social functioning as measured by respective scales. Social bonding also increased in both groups during the study and may be a mechanism for both interventions. Participants found both interventions credible. In this pilot study, Ngoma showed significant and durable beneficial effects comparable to MBSR. The effects of Ngoma and other indigenous rhythm-dance ceremonies on distress and health status in western culture should be investigated in larger clinical studies.

  4. Effect of Ventilation Support on Oxidative Stress and Ischemia-Modified Albumin in Neonates.

    Science.gov (United States)

    Dursun, Arzu; Okumuş, Nurullah; Erol, Sara; Bayrak, Tülin; Zenciroğlu, Ayşegül

    2016-01-01

    Mechanical ventilation (MV) can induce oxidative stress, which plays a critical role in pulmonary injury in intubated neonates. Ischemia-modified albumin (IMA)-a variant of human serum albumin-is a novel biomarker of myocardial ischemia that occurs due to reactive oxygen species during ischemic insult. This study aimed to investigate IMA production due to oxidative stress induced during MV in neonates. This study included 17 neonates that were ventilated using synchronized intermittent mechanical ventilation (SIMV; SIMV group) and 20 neonates ventilated using continuous positive airway pressure (CPAP; CPAP group). Blood samples were collected from each neonate during ventilation support and following cessation of ventilation support. Total antioxidant capacity (TAC) and total oxidant status (TOS) were measured using the Erel method. IMA was measured via an enzyme-linked immunosorbent assay kit (Cusabio Biotech Co., Ltd., Wuhan, China). The oxidant stress index (OSI) was calculated as OSI = TOS/TAC. Statistical analysis was performed using SPSS v.18.0 (SPSS Inc., Chicago, IL) for Windows. Among the neonates included in the study, mean gestational age was 34.7 ± 3.8 weeks, mean birth weight was 2,553 ± 904 g, and 54% were premature. There were not any significant differences in mean gestational age or birth weight between the SIMV and CPAP groups. Among the neonates in both the groups, mean IMA, TOS, and OSI levels were significantly higher during ventilation support (102.2 ± 9.3 IU mL(-1), 15.5 ± 1.3 µmol H2O2 equivalent L(-1), and 0.85 ± 0.22 arbitrary units [ABU], respectively), as compared with following cessation of ventilation support (82.9 ± 11.9 IU mL(-1), 13.4 ± 1.3 µmol H2O2 equivalent L(-1), and 0.64 ± 0.14 ABU, respectively) (p = 0.001). Among all the neonates in the study, mean TAC was significantly lower during ventilation support than the postventilation support (1.82 ± 0.28 mmol 6-hydroxy-2

  5. El Salvador earthquakes: relationships among acute stress disorder symptoms, depression, traumatic event exposure, and resource loss.

    Science.gov (United States)

    Sattler, David N; de Alvarado, Ana Maria Glower; de Castro, Norma Blandon; Male, Robert Van; Zetino, A M; Vega, Raphael

    2006-12-01

    Four and seven weeks after powerful earthquakes in El Salvador, the authors examined the relationships among demographics, traumatic event exposure, social support, resource loss, acute stress disorder (ASD) symptoms, depression, and posttraumatic growth. Participants were 253 college students (Study 1) and 83 people in the community (Study 2). In Study 1, female gender, traumatic event exposure, low social support, and loss of personal characteristic, condition, and energy resources contributed to ASD symptoms and depression. In Study 2, damage to home and loss of personal characteristic and object resources contributed to ASD symptoms and depression. Posttraumatic growth was not associated with ASD symptoms or depression. Findings support the conservation of resources stress theory (Hobfoll, 1998). Resource loss spirals, excessive demands on coping, and exposure to multiple disasters are discussed.

  6. Doxorubicin attached to HPMA copolymer via amide bond modifies the glycosylation pattern of EL4 cells.

    Science.gov (United States)

    Kovar, Lubomir; Etrych, Tomas; Kabesova, Martina; Subr, Vladimir; Vetvicka, David; Hovorka, Ondrej; Strohalm, Jiri; Sklenar, Jan; Chytil, Petr; Ulbrich, Karel; Rihova, Blanka

    2010-08-01

    To avoid the side effects of the anti-cancer drug doxorubicin (Dox), we conjugated this drug to a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer backbone. Dox was conjugated via an amide bond (Dox-HPMA(AM), PK1) or a hydrazone pH-sensitive bond (Dox-HPMA(HYD)). In contrast to Dox and Dox-HPMA(HYD), Dox-HPMA(AM) accumulates within the cell's intracellular membranes, including those of the Golgi complex and endoplasmic reticulum, both involved in protein glycosylation. Flow cytometry was used to determine lectin binding and cell death, immunoblot to characterize the presence of CD7, CD43, CD44, and CD45, and high-performance anion exchange chromatography with pulsed amperometric detector analysis for characterization of plasma membrane saccharide composition. Incubation of EL4 cells with Dox-HPMA(AM) conjugate, in contrast to Dox or Dox-HPMA(HYD), increased the amounts of membrane surface-associated glycoproteins, as well as saccharide moieties recognized by peanut agglutinin, Erythrina cristagalli, or galectin-1 lectins. Only Dox-HPMA(AM) increased expression of the highly glycosylated membrane glycoprotein CD43, while expression of others (CD7, CD44, and CD45) was unaffected. The binding sites for galectin-1 are present on CD43 molecule. Furthermore, we present that EL4 treated with Dox-HPMA(AM) possesses increased sensitivity to galectin-1-induced apoptosis. In this study, we demonstrate that Dox-HPMA(AM) treatment changes glycosylation of the EL4 T cell lymphoma surface and sensitizes the cells to galectin-1-induced apoptosis.

  7. Analytical determination of size-dependent natural frequencies of fully clamped rectangular microplates based on the modified couple stress theory

    Energy Technology Data Exchange (ETDEWEB)

    Askari, Amir R.; Tahani, Masoud [Ferdowsi University of Mashhad, Mashhad (Iran, Islamic Republic of)

    2015-05-15

    This paper presents an analytical and size-dependent model for vibrational analysis of fully clamped rectangular microplates. Modified couple stress theory (MCST) and the Kirchhoff plate model are considered, and Hamilton's principle is employed to derive the size dependent equation of motion that accounts for the effect of residual stresses. The natural frequencies of the microplate are extracted analytically by extended Kantorovich method. The present findings are validated with the available results in the literature, and an excellent agreement is observed between them. In addition, a parametric study is conducted to demonstrate the significant effects of couple stress components on the natural frequencies of fully clamped microplates. The ratio of MCST natural frequencies to those obtained with classical theory depends only on the Poisson's ratio of the plate and is independent of the aspect ratio of the plate for cases with no residual stresses.

  8. Analytical determination of size-dependent natural frequencies of fully clamped rectangular microplates based on the modified couple stress theory

    International Nuclear Information System (INIS)

    Askari, Amir R.; Tahani, Masoud

    2015-01-01

    This paper presents an analytical and size-dependent model for vibrational analysis of fully clamped rectangular microplates. Modified couple stress theory (MCST) and the Kirchhoff plate model are considered, and Hamilton's principle is employed to derive the size dependent equation of motion that accounts for the effect of residual stresses. The natural frequencies of the microplate are extracted analytically by extended Kantorovich method. The present findings are validated with the available results in the literature, and an excellent agreement is observed between them. In addition, a parametric study is conducted to demonstrate the significant effects of couple stress components on the natural frequencies of fully clamped microplates. The ratio of MCST natural frequencies to those obtained with classical theory depends only on the Poisson's ratio of the plate and is independent of the aspect ratio of the plate for cases with no residual stresses.

  9. Ductile failure analysis of defective API X65 pipes based on stress-modified fracture strain criterion

    International Nuclear Information System (INIS)

    Oh, Chang Kyun; Kim, Yun Jae; Baek, Jong Hyun; Kim, Young Pyo; Kim, Woo Sik

    2006-01-01

    A local failure criterion for the API X65 steel is applied to predict ductile failure of full-scale API X65 pipes with simulated corrosion and gouge defects under internal pressure. The local failure criterion is the stress-modified fracture strain for the API X65 steel as a function of the stress triaxiality (defined by the ratio of the hydrostatic stress to the effective stress). Based on detailed FE analyses with the proposed local failure criteria, burst pressures of defective pipes are estimated and compared with experimental data. The predicted burst pressures are in good agreement with experimental data. Noting that an assessment equation against the gouge defect is not yet available, parametric study is performed, from which a simple equation is proposed to predict burst pressure for API X65 pipes with gouge defects

  10. Role of Stress and Smoking as Modifiable Risk Factors for Nonpersistent and Persistent Back Pain in Women.

    Science.gov (United States)

    Schmelzer, Amy C; Salt, Elizabeth; Wiggins, Amanda; Crofford, Leslie J; Bush, Heather; Mannino, David M

    2016-03-01

    The purpose of this study was to examine the association between smoking and stress with nonpersistent and persistent back pain. Participants included 3703 women who took part in the Kentucky Women's Health Registry in 2008 and 2011. Multivariate logistic regression modeling was used to examine whether smoking status and stress levels were predictive of nonpersistent and persistent back pain, controlling for sociodemographic characteristics. Stress level was associated with both nonpersistent and persistent back pain, whereas smoking was associated with only persistent back pain. Current smokers were 1.5 times more likely to report persistent back pain compared with never smokers, controlling for age, race, body mass index, educational attainment, and employment status. Women experiencing large or overwhelming amounts of stress were 1.8 times more likely to have nonpersistent back pain and 1.6 times more likely to report persistent back pain, compared with women experiencing small amounts of stress. This study further substantiates the findings of prior research that describes a significant relationship between back pain, stress, and smoking. Understanding the role of modifiable risk factors (ie, smoking and stress) and their impact on back pain provides an opportunity to offer a comprehensive and tailored treatment plan.

  11. Nonlinear analysis of 0-3 polarized PLZT microplate based on the new modified couple stress theory

    Science.gov (United States)

    Wang, Liming; Zheng, Shijie

    2018-02-01

    In this study, based on the new modified couple stress theory, the size- dependent model for nonlinear bending analysis of a pure 0-3 polarized PLZT plate is developed for the first time. The equilibrium equations are derived from a variational formulation based on the potential energy principle and the new modified couple stress theory. The Galerkin method is adopted to derive the nonlinear algebraic equations from governing differential equations. And then the nonlinear algebraic equations are solved by using Newton-Raphson method. After simplification, the new model includes only a material length scale parameter. In addition, numerical examples are carried out to study the effect of material length scale parameter on the nonlinear bending of a simply supported pure 0-3 polarized PLZT plate subjected to light illumination and uniform distributed load. The results indicate the new model is able to capture the size effect and geometric nonlinearity.

  12. Transgenerational inheritance of modified DNA methylation patterns and enhanced tolerance induced by heavy metal stress in rice (Oryza sativa L.).

    Science.gov (United States)

    Ou, Xiufang; Zhang, Yunhong; Xu, Chunming; Lin, Xiuyun; Zang, Qi; Zhuang, Tingting; Jiang, Lili; von Wettstein, Diter; Liu, Bao

    2012-01-01

    DNA methylation is sensitive and responsive to stressful environmental conditions. Nonetheless, the extent to which condition-induced somatic methylation modifications can impose transgenerational effects remains to be fully understood. Even less is known about the biological relevance of the induced epigenetic changes for potentially altered well-being of the organismal progenies regarding adaptation to the specific condition their progenitors experienced. We analyzed DNA methylation pattern by gel-blotting at genomic loci representing transposable elements and protein-coding genes in leaf-tissue of heavy metal-treated rice (Oryza sativa) plants (S0), and its three successive organismal generations. We assessed expression of putative genes involved in establishing and/or maintaining DNA methylation patterns by reverse transcription (RT)-PCR. We measured growth of the stressed plants and their unstressed progenies vs. the control plants. We found (1) relative to control, DNA methylation patterns were modified in leaf-tissue of the immediately treated plants, and the modifications were exclusively confined to CHG hypomethylation; (2) the CHG-demethylated states were heritable via both maternal and paternal germline, albeit often accompanying further hypomethylation; (3) altered expression of genes encoding for DNA methyltransferases, DNA glycosylase and SWI/SNF chromatin remodeling factor (DDM1) were induced by the stress; (4) progenies of the stressed plants exhibited enhanced tolerance to the same stress their progenitor experienced, and this transgenerational inheritance of the effect of condition accompanying heritability of modified methylation patterns. Our findings suggest that stressful environmental condition can produce transgenerational epigenetic modifications. Progenies of stressed plants may develop enhanced adaptability to the condition, and this acquired trait is inheritable and accord with transmission of the epigenetic modifications. We suggest

  13. Environmental enrichment and gut inflammation modify stress-induced c-Fos expression in the mouse corticolimbic system.

    Directory of Open Access Journals (Sweden)

    Florian Reichmann

    Full Text Available Environmental enrichment (EE has a beneficial effect on rodent behaviour, neuronal plasticity and brain function. Although it may also improve stress coping, it is not known whether EE influences the brain response to an external (psychological stressor such as water avoidance stress (WAS or an internal (systemic stressor such as gastrointestinal inflammation. This study hence explored whether EE modifies WAS-induced activation of the mouse corticolimbic system and whether this stress response is altered by gastritis or colitis. Male C67BL/6N mice were housed under standard or enriched environment for 9 weeks, after which they were subjected to a 1-week treatment with oral iodoacetamide to induce gastritis or oral dextran sulfate sodium to induce colitis. Following exposure to WAS the expression of c-Fos, a marker of neuronal activation, was measured by immunocytochemistry. EE aggravated experimentally induced colitis, but not gastritis, as shown by an increase in the disease activity score and the colonic myeloperoxidase content. In the brain, EE enhanced the WAS-induced activation of the dentate gyrus and unmasked an inhibitory effect of gastritis and colitis on WAS-evoked c-Fos expression within this part of the hippocampus. Conversely, EE inhibited the WAS-evoked activation of the central amygdala and prevented the inhibitory effect of gastritis and colitis on WAS-evoked c-Fos expression in this region. EE, in addition, blunted the WAS-induced activation of the infralimbic cortex and attenuated the inhibitory effect of gastritis and colitis on WAS-evoked c-Fos expression in this area. These data reveal that EE has a region-specific effect on stress-induced c-Fos expression in the corticolimbic system, which is likely to improve stress resilience. The response of the prefrontal cortex - amygdala - hippocampus circuitry to psychological stress is also modified by the systemic stress of gut inflammation, and this interaction between external

  14. Exact solution of a modified El Farol's bar problem: Efficiency and the role of market impact

    Science.gov (United States)

    Marsili, Matteo; Challet, Damien; Zecchina, Riccardo

    2000-06-01

    We discuss a model of heterogeneous, inductive rational agents inspired by the El Farol Bar problem and the Minority Game. As in markets, agents interact through a collective aggregate variable - which plays a role similar to price - whose value is fixed by all of them. Agents follow a simple reinforcement-learning dynamics where the reinforcement, for each of their available strategies, is related to the payoff delivered by that strategy. We derive the exact solution of the model in the “thermodynamic” limit of infinitely many agents using tools of statistical physics of disordered systems. Our results show that the impact of agents on the market price plays a key role: even though price has a weak dependence on the behavior of each individual agent, the collective behavior crucially depends on whether agents account for such dependence or not. Remarkably, if the adaptive behavior of agents accounts even “infinitesimally” for this dependence they can, in a whole range of parameters, reduce global fluctuations by a finite amount. Both global efficiency and individual utility improve with respect to a “price taker” behavior if agents account for their market impact.

  15. History of chronic stress modifies acute stress-evoked fear memory and acoustic startle in male rats.

    Science.gov (United States)

    Schmeltzer, Sarah N; Vollmer, Lauren L; Rush, Jennifer E; Weinert, Mychal; Dolgas, Charles M; Sah, Renu

    2015-01-01

    Chronicity of trauma exposure plays an important role in the pathophysiology of posttraumatic stress disorder (PTSD). Thus, exposure to multiple traumas on a chronic scale leads to worse outcomes than acute events. The rationale for the current study was to investigate the effects of a single adverse event versus the same event on a background of chronic stress. We hypothesized that a history of chronic stress would lead to worse behavioral outcomes than a single event alone. Male rats (n = 14/group) were exposed to either a single traumatic event in the form of electric foot shocks (acute shock, AS), or to footshocks on a background of chronic stress (chronic variable stress-shock, CVS-S). PTSD-relevant behaviors (fear memory and acoustic startle responses) were measured following 7 d recovery. In line with our hypothesis, CVS-S elicited significant increases in fear acquisition and conditioning versus the AS group. Unexpectedly, CVS-S elicited reduced startle reactivity to an acoustic stimulus in comparison with the AS group. Significant increase in FosB/ΔFosB-like immunostaining was observed in the dentate gyrus, basolateral amygdala and medial prefrontal cortex of CVS-S rats. Assessments of neuropeptide Y (NPY), a stress-regulatory transmitter associated with chronic PTSD, revealed selective reduction in the hippocampus of CVS-S rats. Collectively, our data show that cumulative stress potentiates delayed fear memory and impacts defensive responding. Altered neuronal activation in forebrain limbic regions and reduced NPY may contribute to these phenomena. Our preclinical studies support clinical findings reporting worse PTSD outcomes stemming from cumulative traumatization in contrast to acute trauma.

  16. El

    NARCIS (Netherlands)

    de Beer, P.T.; Luttikhuizen, R.; Barbier, J.C.; Gautii, J.

    1998-01-01

    El objetivo de esta publicacisn es aportar una serie de novedosas contribuciones que abordan, desde diversos angulos, el candente problema del empleo. Su contenido se refiere a los principales pamses de la Comunidad Econsmica Europea y Estados Unidos, analizando las caractermsticas y causas del

  17. Spaceflight Modifies Escherichia coli Gene Expression in Response to Antibiotic Exposure and Reveals Role of Oxidative Stress Response

    Directory of Open Access Journals (Sweden)

    Thomas R. Aunins

    2018-03-01

    Full Text Available Bacteria grown in space experiments under microgravity conditions have been found to undergo unique physiological responses, ranging from modified cell morphology and growth dynamics to a putative increased tolerance to antibiotics. A common theory for this behavior is the loss of gravity-driven convection processes in the orbital environment, resulting in both reduction of extracellular nutrient availability and the accumulation of bacterial byproducts near the cell. To further characterize the responses, this study investigated the transcriptomic response of Escherichia coli to both microgravity and antibiotic concentration. E. coli was grown aboard International Space Station in the presence of increasing concentrations of the antibiotic gentamicin with identical ground controls conducted on Earth. Here we show that within 49 h of being cultured, E. coli adapted to grow at higher antibiotic concentrations in space compared to Earth, and demonstrated consistent changes in expression of 63 genes in response to an increase in drug concentration in both environments, including specific responses related to oxidative stress and starvation response. Additionally, we find 50 stress-response genes upregulated in response to the microgravity when compared directly to the equivalent concentration in the ground control. We conclude that the increased antibiotic tolerance in microgravity may be attributed not only to diminished transport processes, but also to a resultant antibiotic cross-resistance response conferred by an overlapping effect of stress response genes. Our data suggest that direct stresses of nutrient starvation and acid-shock conveyed by the microgravity environment can incidentally upregulate stress response pathways related to antibiotic stress and in doing so contribute to the increased antibiotic stress tolerance observed for bacteria in space experiments. These results provide insights into the ability of bacteria to adapt under

  18. Spaceflight Modifies Escherichia coli Gene Expression in Response to Antibiotic Exposure and Reveals Role of Oxidative Stress Response.

    Science.gov (United States)

    Aunins, Thomas R; Erickson, Keesha E; Prasad, Nripesh; Levy, Shawn E; Jones, Angela; Shrestha, Shristi; Mastracchio, Rick; Stodieck, Louis; Klaus, David; Zea, Luis; Chatterjee, Anushree

    2018-01-01

    Bacteria grown in space experiments under microgravity conditions have been found to undergo unique physiological responses, ranging from modified cell morphology and growth dynamics to a putative increased tolerance to antibiotics. A common theory for this behavior is the loss of gravity-driven convection processes in the orbital environment, resulting in both reduction of extracellular nutrient availability and the accumulation of bacterial byproducts near the cell. To further characterize the responses, this study investigated the transcriptomic response of Escherichia coli to both microgravity and antibiotic concentration. E. coli was grown aboard International Space Station in the presence of increasing concentrations of the antibiotic gentamicin with identical ground controls conducted on Earth. Here we show that within 49 h of being cultured, E. coli adapted to grow at higher antibiotic concentrations in space compared to Earth, and demonstrated consistent changes in expression of 63 genes in response to an increase in drug concentration in both environments, including specific responses related to oxidative stress and starvation response. Additionally, we find 50 stress-response genes upregulated in response to the microgravity when compared directly to the equivalent concentration in the ground control. We conclude that the increased antibiotic tolerance in microgravity may be attributed not only to diminished transport processes, but also to a resultant antibiotic cross-resistance response conferred by an overlapping effect of stress response genes. Our data suggest that direct stresses of nutrient starvation and acid-shock conveyed by the microgravity environment can incidentally upregulate stress response pathways related to antibiotic stress and in doing so contribute to the increased antibiotic stress tolerance observed for bacteria in space experiments. These results provide insights into the ability of bacteria to adapt under extreme stress

  19. Spaceflight Modifies Escherichia coli Gene Expression in Response to Antibiotic Exposure and Reveals Role of Oxidative Stress Response

    Science.gov (United States)

    Aunins, Thomas R.; Erickson, Keesha E.; Prasad, Nripesh; Levy, Shawn E.; Jones, Angela; Shrestha, Shristi; Mastracchio, Rick; Stodieck, Louis; Klaus, David; Zea, Luis; Chatterjee, Anushree

    2018-01-01

    Bacteria grown in space experiments under microgravity conditions have been found to undergo unique physiological responses, ranging from modified cell morphology and growth dynamics to a putative increased tolerance to antibiotics. A common theory for this behavior is the loss of gravity-driven convection processes in the orbital environment, resulting in both reduction of extracellular nutrient availability and the accumulation of bacterial byproducts near the cell. To further characterize the responses, this study investigated the transcriptomic response of Escherichia coli to both microgravity and antibiotic concentration. E. coli was grown aboard International Space Station in the presence of increasing concentrations of the antibiotic gentamicin with identical ground controls conducted on Earth. Here we show that within 49 h of being cultured, E. coli adapted to grow at higher antibiotic concentrations in space compared to Earth, and demonstrated consistent changes in expression of 63 genes in response to an increase in drug concentration in both environments, including specific responses related to oxidative stress and starvation response. Additionally, we find 50 stress-response genes upregulated in response to the microgravity when compared directly to the equivalent concentration in the ground control. We conclude that the increased antibiotic tolerance in microgravity may be attributed not only to diminished transport processes, but also to a resultant antibiotic cross-resistance response conferred by an overlapping effect of stress response genes. Our data suggest that direct stresses of nutrient starvation and acid-shock conveyed by the microgravity environment can incidentally upregulate stress response pathways related to antibiotic stress and in doing so contribute to the increased antibiotic stress tolerance observed for bacteria in space experiments. These results provide insights into the ability of bacteria to adapt under extreme stress

  20. The assessment of Big Five Personality Factors and Temperament Domains as modifiers of cardiovascular response to occupational stress.

    Science.gov (United States)

    Merecz, D; Makowska, Z; Makowiec-Dabrowska, T

    1999-01-01

    The aim of the study was to explore the role of Big Five Personality Factors and Temperament Domains as the factors influencing cardiovascular response to work, and their moderating effect on the relationship between occupational stress and cardiovascular reactivity. The self-reported data on occupational stress and filled in NEO-Five Factor Inventory by Costa, and McCrae and Pavlovian Temperament Survey by Strelau et al. were collected from 97 bank clerks employed in large bank branches. The subjects also responded to the questionnaire on personal and professional background factors. A 24 hour monitoring of cardiovascular reactivity (heart rate and blood pressure) was also provided. Conscientiousness was found to be the only modifier of cardiovascular response to occupational stress reflected by systolic blood pressure. Several main, independent of stress effects of personality and temperament domains were also found. The ratio of heart rate at work to heart rate during sleep was associated with the strength of excitatory process, the percentage of maximum heart rate index with Conscientiousness, and systolic blood pressure at work was influenced by the strength of inhibitory process. However, generally speaking, physiological indicators of the cardiovascular system functioning were not very sensitive to changes in values of personality and temperament variables at the level of occupational stress reported by the bank clerks who participated in the study.

  1. Timing matters: the interval between acute stressors within chronic mild stress modifies behavioral and physiologic stress responses in male rats.

    Science.gov (United States)

    Cavigelli, Sonia A; Bao, Alexander D; Bourne, Rebecca A; Caruso, Michael J; Caulfield, Jasmine I; Chen, Mary; Smyth, Joshua M

    2018-04-12

    Chronic mild stress can lead to negative health outcomes. Frequency, duration, and intensity of acute stressors can affect health-related processes. We tested whether the temporal pattern of daily acute stressors (clustered or dispersed across the day) affects depression-related physiology. We used a rodent model to keep stressor frequency, duration, and intensity constant, and experimentally manipulated the temporal pattern of acute stressors delivered during the active phase of the day. Adult male Sprague-Dawley rats were exposed to one of three chronic mild stress groups: Clustered: stressors that occurred within 1 hour of each other (n = 21), Dispersed: stressors that were spread out across the active phase (n = 21), and Control: no stressors presented (n = 21). Acute mild stressors included noise, strobe lights, novel cage, cage tilt, wet bedding, and water immersion. Depression-related outcomes included: sucrose preference, body weight, circulating glucocorticoid (corticosterone) concentration after a novel acute stressor and during basal morning and evening times, and endotoxin-induced circulating interleukin-6 concentrations. Compared to control rats, those in the Clustered group gained less weight, consumed less sucrose, had a blunted acute corticosterone response, and an accentuated acute interleukin-6 response. Rats in the Dispersed group had an attenuated corticosterone decline during the active period and after an acute stressor compared to the Control group. During a chronic mild stress experience, the temporal distribution of daily acute stressors affected health-related physiologic processes. Regular exposure to daily stressors in rapid succession may predict more depression-related symptoms, whereas exposure to stressors dispersed throughout the day may predict diminished glucocorticoid negative feedback.

  2. Correlation of 0.67um scatter with local stress in Ge impacted with the modified Cambridge liquid jet device

    Science.gov (United States)

    Wilson, Michael; Price, D.; Strohecker, Steve

    1994-09-01

    Germanium witness samples were impacted with the NAWCADWAR modified Cambridge liquid jet device introducing varying levels of damage about the center of each sample. Surface damage statistics were collected, scatter measurements were made at 0.67 micrometers and the samples were failed in tension using a bi-axial flexure test setup. The level and character of the damage was correlated with the reflected scatter measurements as a function of local stress and flaw size distribution. Bi-axial flexure data was analyzed to predict fracture stress and the probability of failure of the germanium samples. The mechanical data were then correlated with the scatter data in order to correlate the BRDF with the material failure. The BRDF measurements were taken in several different orientations in order to study the differences in scatter character for the in-plane and out-of-plane conditions.

  3. Cerium oxide nanoparticles alter the salt stress tolerance of Brassica napus L. by modifying the formation of root apoplastic barriers.

    Science.gov (United States)

    Rossi, Lorenzo; Zhang, Weilan; Ma, Xingmao

    2017-10-01

    Rapidly growing global population adds significant strains on the fresh water resources. Consequently, saline water is increasingly tapped for crop irrigation. Meanwhile, rapid advancement of nanotechnology is introducing more and more engineered nanoparticles into the environment and in agricultural soils. While some negative effects of ENPs on plant health at very high concentrations have been reported, more beneficial effects of ENPs at relatively low concentrations are increasingly noticed, opening doors for potential applications of nanotechnology in agriculture. In particular, we found that cerium oxide nanoparticles (CeO 2 NPs) improved plant photosynthesis in salt stressed plants. Due to the close connections between salt stress tolerance and the root anatomical structures, we postulated that CeO 2 NPs could modify plant root anatomy and improve plant salt stress tolerance. This study aimed at testing the hypothesis with Brassica napus in the presence of CeO 2 NPs (0, 500 mg kg -1 dry sand) and/or NaCl (0, 50 mM) in a growth chamber. Free hand sections of fresh roots were taken every seven days for three weeks and the suberin lamellae development was examined under a fluorescence microscope. The results confirmed the hypothesis that CeO 2 NPs modified the formation of the apoplastic barriers in Brassica roots. In salt stressed plants, CeO 2 NPs shortened the root apoplastic barriers which allowed more Na + transport to shoots and less accumulation of Na + in plant roots. The altered Na + fluxes and transport led to better physiological performance of Brassica and may lead to new applications of nanotechnology in agriculture. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Work-related stress in midlife and all-cause mortality: can sense of coherence modify this association?

    Science.gov (United States)

    Nilsen, Charlotta; Andel, Ross; Fritzell, Johan; Kåreholt, Ingemar

    2016-12-01

    Survival reflects the accumulation of multiple influences experienced over the life course. Given the amount of time usually spent at work, the influence of work may be particularly important. We examined the association between work-related stress in midlife and subsequent mortality, investigating whether sense of coherence modified the association. Self-reported work-related stress was assessed in 1393 Swedish workers aged 42-65 who participated in the nationally representative Level of Living Survey in 1991. An established psychosocial job exposure matrix was applied to measure occupation-based stress. Sense of coherence was measured as meaningfulness, manageability and comprehensibility. Mortality data were collected from the Swedish National Cause of Death Register. Data were analyzed with hazard regression with Gompertz distributed baseline intensity. After adjustment for socioeconomic position, occupation-based high job strain was associated with higher mortality in the presence of a weak sense of coherence (HR, 3.15; 1.62-6.13), a result that was stronger in women (HR, 4.48; 1.64-12.26) than in men (HR, 2.90; 1.12-7.49). Self-reported passive jobs were associated with higher mortality in the presence of a weak sense of coherence in men (HR, 2.76; 1.16-6.59). The link between work stress and mortality was not significant in the presence of a strong sense of coherence, indicating that a strong sense of coherence buffered the negative effects of work-related stress on mortality. Modifications to work environments that reduce work-related stress may contribute to better health and longer lives, especially in combination with promoting a sense of coherence among workers. © The Author 2016. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

  5. Complex-Spectrum Magnetic Environment enhances and/or modifies Bioeffects of Hypokinetic Stress Condition: an Animal Study

    Science.gov (United States)

    Temuriantz, N. A.; Martinyuk, V. S.; Ptitsyna, N. G.; Villoresi, G.; Iucci, N.; Tyasto, M. I.; Dorman, L. I.

    During last decades it was shown by many authors that ultra-low and extremely low frequency electric and magnetic fields ULF 0-10 Hz ELF 10-1000 Hz may produce biological effects and consequently may be a possible source for health problems Spaceflight electric and magnetic environments are characterized by complex combination of static and time-varying components in ULF-ELF range and by high variability The objective of this study was to investigate the possible influence of such magnetic fields on rats to understand the pathway regarding functional state of cardiovascular system Magnetic field MF pattern with variable complex spectra in 0-150 Hz frequency range was simulated using 3-axial Helmholtz coils and special computer-based equipment The effect of the real world MF exposure on rats was also tested in combination with hypokinetic stress condition which is typical for spaceflights It was revealed that variable complex-spectrum MF acts as a weak or moderate stress-like factor which amplifies and or modifies the functional shifts caused by other stress-factors The value and direction of the functional shifts caused by MF exposure significantly depend on gender individual-typological constitutional features and also on the physiological state norm stress of organism Our results support the idea that variable complex-spectrum MF action involves sympathetic activation overload in cholesterol transport in blood and also secretor activation of tissue basophyls mast cells that can influence the regional haemodynamics These

  6. Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

    Science.gov (United States)

    Argue, Kathryn J; Neckameyer, Wendi S

    2014-07-01

    The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

  7. Effect of temperature on the rheological properties with shear stress limit of iron oxide nanoparticle modified bentonite drilling muds

    Directory of Open Access Journals (Sweden)

    Ahmed S. Mohammed

    2017-09-01

    Full Text Available In this study, the effect of temperature on the rheological properties and weight loss of a water based bentonite drilling mud modified with iron oxide nanoparticle (nanoFe2O3 was investigated. The bentonite contents in the drilling muds were varied up to 6% by the weight of water and temperature was varied from 25 °C to 85 °C. The nanoFe2O3 content was varied between 0 and 1% by the weight of the drilling mud to modify the rheological properties of the drilling mud. The nanoFe2O3 and bentonite clay were characterized using the X-ray diffraction analysis (XRD and thermal gravimetric analysis (TGA. In the TGA study, the total weight loss at 800 °C for the bentonite decreased from 13% to 1.16%, a 91% reduction when the bentonite clay was mixed with 1% of nanoFe2O3. The results also showed that 1% of nanoFe2O3 increased the rheological properties of the drilling mud. The nanoFe2O3 modification increased the yield stress (τo and plastic viscosity (PV by 45–200% and 20–105% respectively based on the bentonite content and temperature of the drilling mud. The shear thinning behavior of the bentonite drilling mud with and without nanoFe2O3 has been quantified using the hyperbolic model and compared with three parameters Herschel–Bulkley model. The results showed that the hyperbolic model predicted the shear thinning relationship between the shear stress and shear strain rate of the nanoFe2O3 modified bentonite drilling mud very well. Also the hyperbolic model has a maximum shear stress limit whereas the Herschel–Bulkley model did not have a limit on the maximum shear stress. Based on the hyperbolic model the maximum shear stress for the 2%, 4% and 6% bentonite drilling muds without nanoFe2O3 at room temperature were 25 Pa, 35 Pa and 51 Pa respectively. The maximum shear stress for the 2%, 4% and 6% bentonite drilling muds modified with 1% nanoFe2O3 at 25 °C were 59 Pa, 84 Pa and 140 Pa respectively, hence an increase of 135–175

  8. Free vibration analysis of embedded magneto-electro-thermo-elastic cylindrical nanoshell based on the modified couple stress theory

    Science.gov (United States)

    Ghadiri, Majid; Safarpour, Hamed

    2016-09-01

    In this paper, size-dependent effect of an embedded magneto-electro-elastic (MEE) nanoshell subjected to thermo-electro-magnetic loadings on free vibration behavior is investigated. Also, the surrounding elastic medium has been considered as the model of Winkler characterized by the spring. The size-dependent MEE nanoshell is investigated on the basis of the modified couple stress theory. Taking attention to the first-order shear deformation theory (FSDT), the modeled nanoshell and its equations of motion are derived using principle of minimum potential energy. The accuracy of the presented model is validated with some cases in the literature. Finally, using the Navier-type method, an analytical solution of governing equations for vibration behavior of simply supported MEE cylindrical nanoshell under combined loadings is presented and the effects of material length scale parameter, temperature changes, external electric potential, external magnetic potential, circumferential wave numbers, constant of spring, shear correction factor and length-to-radius ratio of the nanoshell on natural frequency are identified. Since there has been no research about size-dependent analysis MEE cylindrical nanoshell under combined loadings based on FSDT, numerical results are presented to be served as benchmarks for future analysis of MEE nanoshells using the modified couple stress theory.

  9. Input-current-shaper based on a modified SEPIC converter with low voltage stress

    DEFF Research Database (Denmark)

    Petersen, Lars

    2001-01-01

    The boost topology is often the designer's first choice when dealing with PFC front-ends. This topology is well documented in the literature and has obvious advantages like continuous input current and low voltage- and current-stress compared to other PFC topologies. The PFC SEPIC converter also...

  10. No effect of melatonin to modify surgical-stress response after major vascular surgery

    DEFF Research Database (Denmark)

    Kücükakin, B.; Wilhelmsen, M.; Lykkesfeldt, Jens

    2010-01-01

    A possible mechanism underlying cardiovascular morbidity after major vascular surgery may be the perioperative ischaemia-reperfusion with excessive oxygen-derived free-radical production and increased levels of circulating inflammatory mediators. We examined the effect of melatonin infusion during...... surgery and oral melatonin treatment for 3 days after surgery on biochemical markers of oxidative and inflammatory stress....

  11. Modified Weibull theory and stress-concentration factors of polycrystalline graphite

    International Nuclear Information System (INIS)

    Ho, F.H.

    1980-12-01

    Stress concentration factors (SCF) due to geometric discontinuities in graphite specimens are observed to be much less than the theoretical SCF in an elastic material. In fact, the experimental SCF is always less than two and sometimes even less than one. A four parameter Weibull theory which recognizes the grain size effect is found to give an adequate explanation of the above observed discrepancies

  12. A Modified Constant-Stress Coupon for Enhanced Natural Crack Start during Fatigue Testing

    Science.gov (United States)

    2016-05-01

    research positions in the University of Sydney and the University of NSW, and was also attached to Pacific Engineering Systems International as a CRC-ACS...Linux–based computer system . A distinct characteristic of shape-optimal designs is the presence of one or more large regions of uniform stress along the...is present (Cetin, Härkegård and Naess 2013). In addition, Molent, Barter and Wanhill (2011) and Barter , Molent and Wanhill (2012) have noted that

  13. Chronic postnatal stress induces voluntary alcohol intake and modifies glutamate transporters in adolescent rats.

    Science.gov (United States)

    Odeon, María Mercedes; Andreu, Marcela; Yamauchi, Laura; Grosman, Mauricio; Acosta, Gabriela Beatriz

    2015-01-01

    Postnatal stress alters stress responses for life, with serious consequences on the central nervous system (CNS), involving glutamatergic neurotransmission and development of voluntary alcohol intake. Several drugs of abuse, including alcohol and cocaine, alter glutamate transport (GluT). Here, we evaluated effects of chronic postnatal stress (CPS) on alcohol intake and brain glutamate uptake and transporters in male adolescent Wistar rats. For CPS from postnatal day (PD) 7, pups were separated from their mothers and exposed to cold stress (4 °C) for 1 h daily for 20 days; controls remained with their mothers. Then they were exposed to either voluntary ethanol (6%) or dextrose (1%) intake for 7 days (5-7 rats per group), then killed. CPS: (1) increased voluntary ethanol intake, (2) did not affect body weight gain or produce signs of toxicity with alcohol exposure, (3) increased glutamate uptake by hippocampal synaptosomes in vitro and (4) reduced protein levels (Western measurements) in hippocampus and frontal cortex of glial glutamate transporter-1 (GLT-1) and excitatory amino-acid transporter-3 (EAAT-3) but increased glutamate aspartate transporter (GLAST) levels. We propose that CPS-induced decrements in GLT-1 and EAAT-3 expression levels are opposed by activation of a compensatory mechanism to prevent excitotoxicity. A greater role for GLAST in total glutamate uptake to prevent enlarged extracellular glutamate levels is inferred. Although CPS strongly increased intake of ethanol, this had little impact on effects of CPS on brain glutamate uptake or transporters. However, the impact of early life adverse events on glutamatergic neurotransmission may underlie increased alcohol consumption in adulthood.

  14. Selenoprotein S/SEPS1 modifies endoplasmic reticulum stress in Z variant alpha1-antitrypsin deficiency.

    LENUS (Irish Health Repository)

    Kelly, Emer

    2009-06-19

    Z alpha(1)-antitrypsin (ZAAT) deficiency is a disease associated with emphysematous lung disease and also with liver disease. The liver disease of AAT deficiency is associated with endoplasmic reticulum (ER) stress. SEPS1 is a selenoprotein that, through a chaperone activity, decreases ER stress. To determine the effect of SEPS1 on ER stress in ZAAT deficiency, we measured activity of the grp78 promoter and levels of active ATF6 as markers of the unfolded protein response in HepG2 cells transfected with the mutant form of AAT, a ZAAT transgene. We evaluated levels of NFkappaB activity as a marker of the ER overload response. To determine the effect of selenium supplementation on the function of SEPS1, we investigated glutathione peroxidase activity, grp78 promoter activity, and NFkappaB activity in the presence or absence of selenium. SEPS1 reduced levels of active ATF6. Overexpression of SEPS1 also inhibited grp78 promoter and NFkappaB activity, and this effect was enhanced in the presence of selenium supplementation. This finding demonstrates a role for SEPS1 in ZAAT deficiency and suggests a possible therapeutic potential for selenium supplementation.

  15. Modifying adolescent interpretation biases through cognitive training: effects on negative affect and stress appraisals.

    Science.gov (United States)

    Telman, Machteld D; Holmes, Emily A; Lau, Jennifer Y F

    2013-10-01

    Adolescent anxiety is common, impairing and costly. Given the scale of adolescent anxiety and its impact, fresh innovations for therapy are in demand. Cognitive Bias Modification of Interpretations (CBM-I) studies of adults show that by training individuals to endorse benign interpretations of ambiguous situations can improve anxious mood-states particularly in response towards stress. While, these investigations have been partially extended to adolescents with success, inconsistent training effects on anxious mood-states have been found. The present study investigated whether positive versus negative CBM-I training influenced appraisals of stress, in forty-nine adolescents, aged 15-18. Data supported the plasticity of interpretational styles, with positively-trained adolescents selecting more benign resolutions of new ambiguous situations, than negatively-trained adolescents. Positively-trained adolescents also rated recent stressors as having less impact on their lives than negatively-trained adolescents. Thus, while negative styles may increase negative responses towards stress, positive styles may boost resilience.

  16. El medio de Kaminski adicionado con nistatina para el aislamiento de dermatofitos y otros hongos patógenos Modified Kaminski agar for the isolation of dermatophytes and some other pathogenic fungi

    Directory of Open Access Journals (Sweden)

    Fernando Montoya

    1989-01-01

    Full Text Available

    Se evaluaron 3 medios de cultivo de composición diferente (Mycobiotic agar, agar de Kaminski y agar de Kaminski adicionado con nistatina para el aislamiento de dermatofitos y el reaislamiento de S. schenckii y hongos negros, agentes de cromomicosis. Con el objeto de puntualizar diferencias entre dichos medios se determinaron, para cada uno, la frecuencia de aislamiento de los hongos, sus características morfológicas y su tiempo de crecimiento, así como la rapidez e Intensidad de la contaminación bacteriana y/o micótica. Se estudiaron 150 muestras de pacientes con sospecha clínica de dermatofitosis y se hicieron 30 reaislamientos de S. schenckiiy 10 de agentes de cromomicosis. Se demostró la utilidad del agar de Kaminski modificado, tanto para el aislamiento como para el reaislamiento de los agentes señalados, a pesar de su mayor índice de contaminación microbiana. Fue, además, útil para el aislamiento de levaduras del género Candida.

    Three culture media with different composition (Mycobiotic agar, Kaminski agarand Kaminski agar modified with nystatin were evaluated for isolation of dermatophytes and reisolation of S. schenckiiand dematiaceous fungi. One hundred and fifty specimens of cases suspicious of dermatophytosis, as well as 30 strains of S. schenckiiand 10 of chromoblatomycosis agents were studied. The modified Kaminski agar was efficient for the isolation and reisolation of the tested agents, in spite of Its greater contamination rate; It was equally adequate for isolation of Candida species.

  17. Chronic restraint-induced stress has little modifying effect on radiation hematopoietic toxicity in mice

    International Nuclear Information System (INIS)

    Wang, Bing; Tanaka, Kaoru; Katsube, Takanori; Ninomiya, Yasuharu; Vares, Guillaume; Nakajima, Tetsuo; Nenoi, Mitsuru; Liu Qiang; Morita, Akinori

    2015-01-01

    Both radiation and stresses cause detrimental effects on humans. Besides possible health effects resulting directly from radiation exposure, the nuclear plant accident is a cause of social psychological stresses. A recent study showed that chronic restraint-induced stresses (CRIS) attenuated Trp53 functions and increased carcinogenesis susceptibility of Trp53-heterozygous mice to total-body X-irradiation (TBXI), having a big impact on the academic world and a sensational effect on the public, especially the residents living in radioactively contaminated areas. It is important to investigate the possible modification effects from CRIS on radiation-induced health consequences in Trp53 wild-type (Trp53wt) animals. Prior to a carcinogenesis study, effects of TBXI on the hematopoietic system under CRIS were investigated in terms of hematological abnormality in the peripheral blood and residual damage in the bone marrow erythrocytes using a mouse restraint model. Five-week-old male Trp53wt C57BL/6J mice were restrained 6 h per day for 28 consecutive days, and TBXI (4 Gy) was given on the 8th day. Results showed that CRIS alone induced a marked decrease in the red blood cell (RBC) and the white blood cell (WBC) count, while TBXI caused significantly lower counts of RBCs, WBCs and blood platelets, and a lower concentration of hemoglobin regardless of CRIS. CRIS alone did not show any significant effect on erythrocyte proliferation and on induction of micronucleated erythrocytes, whereas TBXI markedly inhibited erythrocyte proliferation and induced a significant increase in the incidences of micronucleated erythrocytes, regardless of CRIS. These findings suggest that CRIS does not have a significant impact on radiation-induced detrimental effects on the hematopoietic system in Trp53wt mice. (author)

  18. Sex and Trait Anxiety Differences in Psychological Stress are Modified by Environment.

    Science.gov (United States)

    Liu, James; Scira, John; Donaldson, Simone; Kajiji, Nina; Dash, Gordon H; Donaldson, S Tiffany

    2018-05-09

    Evidence-based research has revealed how physiological and emotional responses to acute stress are adaptive. However, under conditions of unpredictable or protracted stress, health and drug vulnerability can be compromised. In this study, we examined anxiety-like behavioral responses of 4th generation adolescent male and female Long Evans rats selectively bred for high (HAn) and low (LAn) anxiety-like behavior when housed in an isolated environment (IE) versus a social environment (SE). After 35 days in IE or SE, animals were tested in the elevated plus maze (EPM), injected with amphetamine (AMPH: 0.5 mg/kg, IP) in the locomotor activity (LMA) chamber, measured for basal and post air puff-stressor core body temperature and blood pressure. Following select rearing, SE reduced the anxiogenic response in HAn rats with females displaying the lowest anxiety-like behavior in the EPM. During habituation in the LMA, IE rats remained active, while post-AMPH injection HAn females were hyperactive, followed closely by LAn females. Our findings from the post-stressor physiological measurements indicate that temperature differences due to environment are observed only in the SE females. We also observed group differences for diastolic (DBP) and systolic (SBP) blood pressure. HAn IE males experienced higher DBP and SBP but LAn IE females only experienced higher SBP. Not only do our findings corroborate earlier work on HAn/LAn lines but the findings obtained from this research offer new insights about the role of environment and the role of sex in (1) modulation of anxiety-like behavior, (2) AMPH sensitivity, and (3) basal and stress-induced physiological changes. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Mechanical analysis of non-uniform bi-directional functionally graded intelligent micro-beams using modified couple stress theory

    Science.gov (United States)

    Bakhshi Khaniki, Hossein; Rajasekaran, Sundaramoorthy

    2018-05-01

    This study develops a comprehensive investigation on mechanical behavior of non-uniform bi-directional functionally graded beam sensors in the framework of modified couple stress theory. Material variation is modelled through both length and thickness directions using power-law, sigmoid and exponential functions. Moreover, beam is assumed with linear, exponential and parabolic cross-section variation through the length using power-law and sigmoid varying functions. Using these assumptions, a general model for microbeams is presented and formulated by employing Hamilton’s principle. Governing equations are solved using a mixed finite element method with Lagrangian interpolation technique, Gaussian quadrature method and Wilson’s Lagrangian multiplier method. It is shown that by using bi-directional functionally graded materials in nonuniform microbeams, mechanical behavior of such structures could be affected noticeably and scale parameter has a significant effect in changing the rigidity of nonuniform bi-directional functionally graded beams.

  20. Dynamic pull-in instability of geometrically nonlinear actuated micro-beams based on the modified couple stress theory

    Directory of Open Access Journals (Sweden)

    Hamid M. Sedighi

    Full Text Available This paper investigates the dynamic pull-in instability of vibrating micro-beams undergoing large deflection under electrosatically actuation. The governing equation of motion is derived based on the modified couple stress theory. Homotopy Perturbation Method is employed to produce the high accuracy approximate solution as well as the second-order frequency- amplitude relationship. The nonlinear governing equation of micro beam vibrations predeformed by an electric field includes both even and odd nonlinearities. The influences of basic non-dimensional parameters on the pull-in instability as well as the natural frequency are studied. It is demonstrated that two terms in series expansions are sufficient to produce high accuracy solution of the micro-structure. The accuracy of proposed asymptotic approach is validated via numerical results. The phase portrait of the system exhibits periodic and homoclinic orbits.

  1. Neural correlates of the modified Stroop effect in post-traumatic stress disorder: an event-related potential study.

    Science.gov (United States)

    Chen, Xiaoyi; Wei, Dongtao; Dupuis-Roy, Nicolas; Du, Xue; Qiu, Jiang; Zhang, Qinglin

    2012-12-19

    Previous studies have provided electrophysiological evidence for attentional abnormalities in patients with post-traumatic stress disorder (PTSD). The present study examined the electrophysiological activity of trauma-exposed patients with or without a PTSD during a modified Stroop task. The PTSD group showed a reduced P2 and P3 amplitude relative to the non-PTSD group under both the earthquake-related and earthquake-unrelated words conditions. Importantly, the earthquake-related words elicited a greater P3 amplitude (350-450 ms after stimulus) than did unrelated words in the non-PTSD group, whereas no significant difference was found in the PTSD group. This indicates that PTSD patients had some attention deficits compared with non-PTSD individuals, and that these attention deficits were not just limited to earthquake-related words.

  2. DAF-2/insulin-like signaling in C. elegans modifies effects of dietary restriction and nutrient stress on aging, stress and growth.

    Directory of Open Access Journals (Sweden)

    Wendy B Iser

    2007-11-01

    Full Text Available Dietary restriction (DR and reduced insulin/IGF-I-like signaling (IIS are two regimens that promote longevity in a variety of organisms. Genetic analysis in C. elegans nematodes has shown that DR and IIS couple to distinct cellular signaling pathways. However, it is not known whether these pathways ultimately converge on overlapping or distinct targets to extend lifespan.We investigated this question by examining additional effects of DR in wildtype animals and in daf-2 mutants with either moderate or severe IIS deficits. Surprisingly, DR and IIS had opposing effects on these physiological processes. First, DR induced a stress-related change in intestinal vesicle trafficking, termed the FIRE response, which was suppressed in daf-2 mutants. Second, DR did not strongly affect expression of a daf-2- and stress-responsive transcriptional reporter. Finally, DR-related growth impairment was suppressed in daf-2 mutants.These findings reveal that an important biological function of DAF-2/IIS is to enhance growth and survival under nutrient-limited conditions. However, we also discovered that levels of DAF-2 pathway activity modified the effects of DR on longevity. Thus, while DR and IIS clearly affect lifespan through independent targets, there may also be some prolongevity targets that are convergently regulated by these pathways.

  3. DAF-2/insulin-like signaling in C. elegans modifies effects of dietary restriction and nutrient stress on aging, stress and growth.

    Science.gov (United States)

    Iser, Wendy B; Wolkow, Catherine A

    2007-11-28

    Dietary restriction (DR) and reduced insulin/IGF-I-like signaling (IIS) are two regimens that promote longevity in a variety of organisms. Genetic analysis in C. elegans nematodes has shown that DR and IIS couple to distinct cellular signaling pathways. However, it is not known whether these pathways ultimately converge on overlapping or distinct targets to extend lifespan. We investigated this question by examining additional effects of DR in wildtype animals and in daf-2 mutants with either moderate or severe IIS deficits. Surprisingly, DR and IIS had opposing effects on these physiological processes. First, DR induced a stress-related change in intestinal vesicle trafficking, termed the FIRE response, which was suppressed in daf-2 mutants. Second, DR did not strongly affect expression of a daf-2- and stress-responsive transcriptional reporter. Finally, DR-related growth impairment was suppressed in daf-2 mutants. These findings reveal that an important biological function of DAF-2/IIS is to enhance growth and survival under nutrient-limited conditions. However, we also discovered that levels of DAF-2 pathway activity modified the effects of DR on longevity. Thus, while DR and IIS clearly affect lifespan through independent targets, there may also be some prolongevity targets that are convergently regulated by these pathways.

  4. The biological age linked to oxidative stress modifies breast cancer aggressiveness.

    Science.gov (United States)

    Sáez-Freire, María Del Mar; Blanco-Gómez, Adrián; Castillo-Lluva, Sonia; Gómez-Vecino, Aurora; Galvis-Jiménez, Julie Milena; Martín-Seisdedos, Carmen; Isidoro-García, María; Hontecillas-Prieto, Lourdes; García-Cenador, María Begoña; García-Criado, Francisco Javier; Patino-Alonso, María Carmen; Galindo-Villardón, Purificación; Mao, Jian-Hua; Prieto, Carlos; Castellanos-Martín, Andrés; Kaderali, Lars; Pérez-Losada, Jesús

    2018-03-14

    The incidence of breast cancer increases with age until menopause, and breast cancer is more aggressive in younger women. The existence of epidemiological links between breast cancer and aging indicates that both processes share some common mechanisms of development. Oxidative stress is associated with both cancer susceptibility and aging. Here we observed that ERBB2-positive breast cancer, which developed in genetically heterogeneous ERBB2-positive transgenic mice generated by a backcross, is more aggressive in chronologically younger than in older mice (differentiated by the median survival of the cohort that was 79 weeks), similar to what occurs in humans. In this cohort, we estimated the oxidative biological age using a mathematical model that integrated several subphenotypes directly or indirectly related to oxidative stress. The model selected the serum levels of HDL-cholesterol and magnesium and total AKT1 and glutathione concentrations in the liver. The grade of aging was calculated as the difference between the predicted biological age and the chronological age. This comparison permitted the identification of biologically younger and older mice compared with their chronological age. Interestingly, biologically older mice developed more aggressive breast cancer than the biologically younger mice. Genomic regions on chromosomes 2 and 15 linked to the grade of oxidative aging were identified. The levels of expression of Zbp1 located on chromosome 2, a gene related to necroptosis and inflammation, positively correlated with the grade of aging and tumour aggressiveness. Moreover, the pattern of gene expression of genes linked to the inflammation and the response to infection pathways was enriched in the livers of biologically old mice. This study shows part of the complex interactions between breast cancer and aging. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Ovarian hormones modify anxiety behavior and glucocorticoid receptors after chronic social isolation stress.

    Science.gov (United States)

    Ramos-Ortolaza, Dinah L; Doreste-Mendez, Raura J; Alvarado-Torres, John K; Torres-Reveron, Annelyn

    2017-06-15

    Chronic social isolation could lead to a disruption in the Hypothalamic-Pituitary-Adrenal (HPA) axis, resulting in anxiety and depressive-like behaviors but cycling estrogens could modify these behaviors. The aim of this study was to determine if changes in ovarian hormones during the normal cycle could interact with social isolation to alter anxiety and depressive-like behaviors. In parallel, we examined the expression of glucocorticoid receptor (GR) and synaptic vesicle protein synaptophysin in the hippocampus and hypothalamus of Sprague Dawley normal cycling female rats. We assigned rats to either isolated or paired housing for 8 weeks. To assess anxiety and depressive-like behaviors, we used the open field test and forced swim test, respectively. Female rats were tested at either diestrus, estrus, or proestrus stage of the estrous cycle. After behaviors, rats were perfused and brains collected. Brain sections containing hippocampus and hypothalamus were analyzed using immunohistochemistry for synaptophysin and glucocorticoid receptor (GR) levels. We found an increase in depressive-like behaviors for isolated animals compared to paired housed rats, regardless of the estrous cycle stage. Interestingly, we found a decrease in anxiety behaviors in females in the estrus stage accompanied by a decrease in GR expression in hippocampal DG and CA3. However, no changes in synaptophysin were observed in any of the areas of studied. Our results support the beneficial effects of circulating ovarian hormones in anxiety, possibly by decreasing GR expression. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Modified Application of Nitrogen Fertilizer for Increasing Rice Variety Tolerance toward Submergence Stress

    Directory of Open Access Journals (Sweden)

    Gribaldi Gribaldi

    2017-01-01

    Full Text Available This research was conducted from July to October 2015, using Randomized Block Design with two treatment factors and three replications for each treatment. The first factor was rice varieties (V: V1 = IR 64; V2 = Inpara 5. The second factor was fertilizer (N: N0: without submergence, all N fertilizer was given during planting; N1: all N fertilizer dose was given during planting; and N2: 1/2 dose of N fertilizer was given during planting; the rest was given at 42 days after planting. The submergence was during 7–14 days after planting; N3 = the entire dose of N fertilizer that was given during planting, N4 = 1/2 the dose of N fertilizer that was given during planting, and the rest was given at 42 days after planting. The submergence was during 7–14 and 28–35 days after planting. The results showed that the management of nitrogen fertilizer application had effect on rice growth and production which experienced dirty water submergence stress; the application of 1/2 dose of N fertilizer given during planting had the best effect on rice growth and production; the longer the submergence period for rice variety, the higher the effect on rice growth and production.

  7. Coping strategy and social support modify the association between perceived stress and C-reactive protein: a longitudinal study of healthy men and women.

    Science.gov (United States)

    Shimanoe, Chisato; Hara, Megumi; Nishida, Yuichiro; Nanri, Hinako; Otsuka, Yasuko; Horita, Mikako; Yasukata, Jun; Miyoshi, Nobuyuki; Yamada, Yosuke; Higaki, Yasuki; Tanaka, Keitaro

    2018-05-01

    Inconsistent associations have been reported between perceived stress and C-reactive protein (CRP), a marker of systemic inflammation. We previously observed a male-specific inverse relationship between perceived stress and CRP in a cross-sectional study. In the present study, we examined the longitudinal association between changes in perceived stress and CRP, and further analyzed whether changes in coping strategies and social support modify this association. This study included 8454 participants in both a baseline survey and a follow-up survey 5 years later. Psychosocial measures (i.e. perceived stress, coping strategies, and social support) and CRP concentrations were measured by identical means in both surveys. Consistent with our previous findings, increased perceived stress was significantly associated with lower CRP in men (p trend  = .037), but not in women. Increased "emotional expression," a coping strategy, was also associated with lower CRP in women (p trend  = .024). Furthermore, interactions between perceived stress and a coping strategy (positive reappraisal) or social support on CRP were found in men (p interaction  = .007 and .038, respectively); the above inverse association between stress and CRP was not detected for participants with diminished positive reappraisal or social support. In conclusion, increases in perceived stress during a 5-year period were associated with decreases in CRP among healthy men, and the observed association was possibly modified by coping strategy or social support.

  8. Medio EMJH modificado para el cultivo de Leptospira interrogans serogrupo Ballum Modified EMJH medium for cultivation of Leptospira interrogans serogroup Ballum

    Directory of Open Access Journals (Sweden)

    A. González

    2006-04-01

    Full Text Available El serogrupo Ballum agrupa cepas de crecimiento fastidioso, con requerimientos nutricionales más exigentes que otras cepas patógenas de Leptospira. Fue evaluada la influencia de 37 compuestos nutricionales sobre el crecimiento de Leptospira interrogans serogrupo Ballum, tomando como base para el estudio al medio sintético EMJH. El crecimiento microbiano fue estimado espectrofotométricamente y por conteo directo en cámara de Petroff-Hausser. La estabilidad de la virulencia fue evaluada en hamsters mediante el cálculo de la dosis letal media. La estabilidad de la antigenicidad fue evaluada mediante Western blotting con antisuero policlonal específico. Bajo condiciones de cultivo controladas se logró triplicar los rendimientos de biomasa comúnmente obtenidos en el medio EMJH sin afectación de la virulencia y antigenicidad tras el incremento de la concentración de Tween 80 y la incorporación de acetato de sodio y extracto de carne. El incremento de la concentración de al menos 6 componentes del EMJH o la incorporación de una variedad de nuevos nutrientes no estimularon apreciablemente los rendimientos de biomasa o la velocidad específica de crecimiento del microorganismo. Los resultados obtenidos permiten disponer de un medio de cultivo enriquecido capaz de sustentar elevados rendimientos de biomasa de este serogrupo exigente de mayor circulación en humanos en Cuba.Strains within the Ballum serogroup of spirochete Leptospira show fastidious growth with more exigent nutritional requirements than those of other Leptospira pathogenic strains. The influence of 37 nutritional compounds on the growth of Leptospira interrogans serogroup Ballum was investigated employing the synthetic EMJH medium as the base for the study. Microbial growth was estimated spectrophotometrically and direct counts were performed with a Petroff-Hausser counting chamber. Virulence stability was evaluated by calculating the mean lethal dose in hamsters

  9. Sorbitol-modified hyaluronic acid reduces oxidative stress, apoptosis and mediators of inflammation and catabolism in human osteoarthritic chondrocytes.

    Science.gov (United States)

    Mongkhon, John-Max; Thach, Maryane; Shi, Qin; Fernandes, Julio C; Fahmi, Hassan; Benderdour, Mohamed

    2014-08-01

    Our study was designed to elucidate the precise molecular mechanisms by which sorbitol-modified hyaluronic acid (HA/sorbitol) exerts beneficial effects in osteoarthritis (OA). Human OA chondrocytes were treated with increasing doses of HA/sorbitol ± anti-CD44 antibody or with sorbitol alone and thereafter with or without interleukin-1beta (IL-1β) or hydrogen peroxide (H2O2). Signal transduction pathways and parameters related to oxidative stress, apoptosis, inflammation, and catabolism were investigated. HA/sorbitol prevented IL-1β-induced oxidative stress, as measured by reactive oxygen species, p47-NADPH oxidase phosphorylation, 4-hydroxynonenal (HNE) production and HNE-metabolizing glutathione-S-transferase A4-4 expression. Moreover, HA/sorbitol stifled IL-1β-induced metalloproteinase-13, nitric oxide (NO) and prostaglandin E2 release as well as inducible NO synthase expression. Study of the apoptosis process revealed that this gel significantly attenuated cell death, caspase-3 activation and DNA fragmentation elicited by exposure to a cytotoxic H2O2 dose. Examination of signaling pathway components disclosed that HA/sorbitol prevented IL-1β-induced p38 mitogen-activated protein kinase and nuclear factor-kappa B activation, but not that of extracellular signal-regulated kinases 1 and 2. Interestingly, the antioxidant as well as the anti-inflammatory and anti-catabolic effects of HA/sorbitol were attributed to sorbitol and HA, respectively. Altogether, our findings support a beneficial effect of HA/sorbitol in OA through the restoration of redox status and reduction of apoptosis, inflammation and catabolism involved in cartilage damage.

  10. Sensitization behaviour of modified 316N and 316L stainless steel weld metals after complex annealing and stress relieving cycles

    International Nuclear Information System (INIS)

    Parvathavarthini, N.; Dayal, R.K.; Khatak, H.S.; Shankar, V.; Shanmugam, V.

    2006-01-01

    Sensitization behaviour of austenitic stainless steel weld metals prepared using indigenously developed modified 316N (C = 0.05%; N = 0.12%) and 316L (C = 0.02%; N = 0.07%) electrodes was studied. Detailed optical and scanning electron microscopic examination was carried out to understand the microstructural changes occurring in the weld metal during isothermal exposure at various temperatures ranging from 500 deg. C to 850 deg. C (773-1123 K). Based on these studies the mechanism of sensitization in the austenite-ferrite weld metal has been explained. Time-temperature-sensitization (TTS) diagrams were established using ASTM A262 Practice E test. From the TTS diagrams, critical cooling rate (CCR) above which there is no risk of sensitization was calculated for both materials. The heating/cooling rates to be followed for avoiding sensitization during heat treatment cycles consisting of solution-annealing and stress-relieving in fabrication of welded components of AISI 316LN stainless steel (SS) were estimated taking into account the soaking time and the number of times the component undergoes thermal excursions in the sensitization regime. The results were validated by performing controlled heating and cooling heat treatment trials on welded specimens

  11. Vibration analysis of rotating functionally graded Timoshenko microbeam based on modified couple stress theory under different temperature distributions

    Science.gov (United States)

    Ghadiri, Majid; Shafiei, Navvab

    2016-04-01

    In this study, thermal vibration of rotary functionally graded Timoshenko microbeam has been analyzed based on modified couple stress theory considering temperature change in four types of temperature distribution on thermal environment. Material properties of FG microbeam are supposed to be temperature dependent and vary continuously along the thickness according to the power-law form. The axial forces are also included in the model as the thermal and true spatial variation due to the rotation. Governing equations and boundary conditions have been derived by employing Hamiltonian's principle. The differential quadrature method is employed to solve the governing equations for cantilever and propped cantilever boundary conditions. Validations are done by comparing available literatures and obtained results which indicate accuracy of applied method. Results represent effects of temperature changes, different boundary conditions, nondimensional angular velocity, length scale parameter, different boundary conditions, FG index and beam thickness on fundamental, second and third nondimensional frequencies. Results determine critical values of temperature changes and other essential parameters which can be applicable to design micromachines like micromotor and microturbine.

  12. Vibration analysis of a rotating functionally graded tapered microbeam based on the modified couple stress theory by DQEM

    Science.gov (United States)

    Ghadiri, Majid; Shafiei, Navvab; Alireza Mousavi, S.

    2016-09-01

    Due to having difficulty in solving governing nonlinear differential equations of a non-uniform microbeam, a few numbers of authors have studied such fields. In the present study, for the first time, the size-dependent vibration behavior of a rotating functionally graded (FG) tapered microbeam based on the modified couple stress theory is investigated using differential quadrature element method (DQEM). It is assumed that physical and mechanical properties of the FG microbeam are varying along the thickness that will be defined as a power law equation. The governing equations are determined using Hamilton's principle, and DQEM is presented to obtain the results for cantilever and propped cantilever boundary conditions. The accuracy and validity of the results are shown in several numerical examples. In order to display the influence of size on the first two natural frequencies and consequently changing of some important microbeam parameters such as material length scale, rate of cross section, angular velocity and gradient index of the FG material, several diagrams and tables are represented. The results of this article can be used in designing and optimizing elastic and rotary-type micro-electro-mechanical systems like micro-motors and micro-robots including rotating parts.

  13. 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 ...

  14. Maternal separation in early life modifies anxious behavior and Fos and glucocorticoid receptor expression in limbic neurons after chronic stress in rats: effects of tianeptine.

    Science.gov (United States)

    Trujillo, Verónica; Durando, Patricia E; Suárez, Marta M

    2016-01-01

    Early-life adversity can lead to long-term consequence persisting into adulthood. Here, we assess the implications of an adverse early environment on vulnerability to stress during adulthood. We hypothesized that the interplay between early and late stress would result in a differential phenotype regarding the number of neurons immunoreactive for glucocorticoid receptor (GR-ir) and neuronal activity as assessed by Fos immunoreactivity (Fos-ir) in brain areas related to stress responses and anxiety-like behavior. We also expected that the antidepressant tianeptine could correct some of the alterations induced in our model. Male Wistar rats were subjected to daily maternal separation (MS) for 4.5 h during the first 3 weeks of life. As adults, the rats were exposed to chronic stress for 24 d and they were treated daily with tianeptine (10 mg/kg intraperitoneal) or vehicle (isotonic saline). Fos-ir was increased by MS in all structures analyzed. Chronic stress reduced Fos-ir in the hippocampus, but increased it in the paraventricular nucleus. Furthermore, chronic stress increased GR-ir in hippocampus (CA1) and amygdala in control non-MS rats. By contrast, when MS and chronic stress were combined, GR-ir was decreased in these structures. Additionally, whereas tianeptine did not affect Fos-ir, it regulated GR-ir in a region-dependent manner, in hippocampus and amygdala opposing in some cases the stress or MS effects. Furthermore, tianeptine reversed the MS- or stress-induced anxious behavior. The interplay between MS and chronic stress observed indicates that MS rats have a modified phenotype, which is expressed when they are challenged by stress in later life.

  15. A Modified Johnson-Cook Model for Sheet Metal Forming at Elevated Temperatures and Its Application for Cooled Stress-Strain Curve and Spring-Back Prediction

    International Nuclear Information System (INIS)

    Duc-Toan, Nguyen; Tien-Long, Banh; Young-Suk, Kim; Dong-Won, Jung

    2011-01-01

    In this study, a modified Johnson-Cook (J-C) model and an innovated method to determine (J-C) material parameters are proposed to predict more correctly stress-strain curve for tensile tests in elevated temperatures. A MATLAB tool is used to determine material parameters by fitting a curve to follow Ludwick's hardening law at various elevated temperatures. Those hardening law parameters are then utilized to determine modified (J-C) model material parameters. The modified (J-C) model shows the better prediction compared to the conventional one. As the first verification, an FEM tensile test simulation based on the isotropic hardening model for boron sheet steel at elevated temperatures was carried out via a user-material subroutine, using an explicit finite element code, and compared with the measurements. The temperature decrease of all elements due to the air cooling process was then calculated when considering the modified (J-C) model and coded to VUMAT subroutine for tensile test simulation of cooling process. The modified (J-C) model showed the good agreement between the simulation results and the corresponding experiments. The second investigation was applied for V-bending spring-back prediction of magnesium alloy sheets at elevated temperatures. Here, the combination of proposed J-C model with modified hardening law considering the unusual plastic behaviour for magnesium alloy sheet was adopted for FEM simulation of V-bending spring-back prediction and shown the good comparability with corresponding experiments.

  16. The radiation stress and beaches; El tensor de radiacion y las playas

    Energy Technology Data Exchange (ETDEWEB)

    Lechuga Alvaro, A. [Ministerio de Fomento (Spain)

    1998-06-01

    In this paper we summarize the main characteristics of the radiation stress on shallow water and its relation ship with the sediment transport. After Longuet-Higguins and Stewart presented the concept and applications of the radiation stress there have been several studies showing some aspects of the integral characteristics of the wave nonlinearity. First of all we describe the radiation stress and its components when we change coordinates. Thirdly we generalize the coordinates using the differential operators in orthogonal curvilinear coordinates. The problem is strongly simplified and also is the sedimentary circulation and dynamics. A quick look at the term of the equation shows us the main characteristics of sediment transports both in deep and shallow water. Some conclusions can be drawn of it. (Author)

  17. El estres y los ninos pequenos (Stress and Young Children). ERIC Digest.

    Science.gov (United States)

    Jewett, Jan; Peterson, Karen

    Traditionally, stress has been defined in terms of its source (internal, such as hunger, pain, sensitivity to noise and external, such as separation from family, change in family composition, exposure to conflict or violence). Although the research literature tends to focus on the impact of single-variable stressors on children's development, in…

  18. Docosahexaenoic acid modifies the clustering and size of lipid rafts and the lateral organization and surface expression of MHC class I of EL4 cells.

    Science.gov (United States)

    Shaikh, Saame Raza; Rockett, Benjamin Drew; Salameh, Muhammad; Carraway, Kristen

    2009-09-01

    An emerging molecular mechanism by which docosahexaenoic acid (DHA) exerts its effects is modification of lipid raft organization. The biophysical model, based on studies with liposomes, shows that DHA avoids lipid rafts because of steric incompatibility between DHA and cholesterol. The model predicts that DHA does not directly modify rafts; rather, it incorporates into nonrafts to modify the lateral organization and/or conformation of membrane proteins, such as the major histocompatibility complex (MHC) class I. Here, we tested predictions of the model at a cellular level by incorporating oleic acid, eicosapentaenoic acid (EPA), and DHA, compared with a bovine serum albumin (BSA) control, into the membranes of EL4 cells. Quantitative microscopy showed that DHA, but not EPA, treatment, relative to the BSA control diminished lipid raft clustering and increased their size. Approximately 30% of DHA was incorporated directly into rafts without changing the distribution of cholesterol between rafts and nonrafts. Quantification of fluorescence colocalization images showed that DHA selectively altered MHC class I lateral organization by increasing the fraction of the nonraft protein into rafts compared with BSA. Both DHA and EPA treatments increased antibody binding to MHC class I compared with BSA. Antibody titration showed that DHA and EPA did not change MHC I conformation but increased total surface levels relative to BSA. Taken together, our findings are not in agreement with the biophysical model. Therefore, we propose a model that reconciles contradictory viewpoints from biophysical and cellular studies to explain how DHA modifies lipid rafts on several length scales. Our study supports the notion that rafts are an important target of DHA's mode of action.

  19. Rheological and mechanical properties and interfacial stress development of composite cements modified with thio-urethane oligomers.

    Science.gov (United States)

    Bacchi, Ataís; Pfeifer, Carmem S

    2016-08-01

    Thio-urethane oligomers have been shown to reduce stress and increase toughness in highly filled composite materials. This study evaluated the influence of thio-urethane backbone structure on rheological and mechanical properties of resin cements modified with a fixed concentration of the oligomers. Thio-urethane oligomers (TU) were synthesized by combining thiols - pentaerythritol tetra-3-mercaptopropionate (PETMP) or trimethylol-tris-3-mercaptopropionate (TMP) - with isocyanates - 1,6-hexanediol-diissocyante (HDDI) (aliphatic) or 1,3-bis(1-isocyanato-1-methylethyl)benzene (BDI) (aromatic) or dicyclohexylmethane 4,4'-diisocyanate (HMDI) (cyclic), at 1:2 isocyanate:thiol, leaving pendant thiols. 20wt% TU were added to BisGMA-UDMA-TEGDMA (5:3:2). 60wt% silanated inorganic fillers were added. Near-IR was used to follow methacrylate conversion and rate of polymerization ( [Formula: see text] ). Mechanical properties were evaluated in three-point bending (ISO 4049) for flexural strength/modulus (FS/FM, and toughness), and notched specimens (ASTM Standard E399-90) for fracture toughness (KIC). PS was measured on the Bioman. Viscosity (V) and gel-points (defined as the crossover between storage and loss shear moduli (G'/G″)) were obtained with rheometry. Glass transition temperature (Tg), cross-link density and homogeneity of the network were obtained with dynamic mechanical analysis. Film-thickness was evaluated according to ISO 4049. DC and mechanical properties increased and [Formula: see text] and PS decreased with the addition of TUs. Gelation (G'/G″) was delayed and DC at G'/G″ increased in TU groups. Tg and cross-link density dropped in TU groups, while oligomers let to more homogenous networks. An increase in V was observed, with no effect on film-thickness. Significant reductions in PS were achieved at the same time conversion and mechanical properties increased. The addition of thio-urethane oligomers proved successful in improving several key properties

  20. Elevation of liver endoplasmic reticulum stress in a modified choline-deficient l-amino acid-defined diet-fed non-alcoholic steatohepatitis mouse model.

    Science.gov (United States)

    Muraki, Yo; Makita, Yukimasa; Yamasaki, Midori; Amano, Yuichiro; Matsuo, Takanori

    2017-05-06

    Endoplasmic reticulum (ER) stress caused by accumulation of misfolded proteins is observed in several kinds of diseases. Since ER stress is reported to be involved in the progression of non-alcoholic steatohepatitis (NASH), highly sensitive and simple measurement methods are required for research into developing novel therapy for NASH. To investigate the involvement of ER stress in NASH pathogenesis in a mouse model, an assay for liver ER stress was developed using ER stress activated indicator-luciferase (ERAI-Luc) mice. To establish the assay method for detection of ER stress in the liver, tunicamycin (TM) (0.3 mg/kg i. p.) was administered to ERAI-Luc mice, and the luciferase activity was measured in ex vivo and in vivo. To evaluate ER stress in the NASH model, ERAI-Luc mice were fed a modified choline-deficient l-amino acid-defined (mCDAA) diet for 14 weeks. After measurement of ER stress by luminescence imaging, levels of liver lipids and pro-fibrotic and pro-inflammatory gene expression were measured as NASH-related indexes. In non-invasive whole-body imaging, TM elevated luciferase activity in the liver, induced by activation of ER stress. The highest luminescence in the liver was confirmed by ex vivo imaging of isolated tissues. In parallel with progression of NASH, elevated luminescence induced by ER stress in liver was observed in mCDAA diet-fed ERAI-Luc mice. Luciferase activity was significantly and positively correlated to levels of triglyceride and free cholesterol in the liver, as well as to the mRNA expression of type 1 collagen α1 chain and tumor necrosis factor α. These data indicated that the use of ERAI-Luc mice was effective in the detection of ER stress in the liver. Moreover, the NASH model using ERAI-Luc mice can be a useful tool to clarify the role of ER stress in pathogenesis of NASH and to evaluate effects of drugs targeted against ER stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Intervention to reduce heat stress and improve efficiency among sugarcane workers in El Salvador: Phase 1.

    Science.gov (United States)

    Bodin, T; García-Trabanino, R; Weiss, I; Jarquín, E; Glaser, J; Jakobsson, K; Lucas, R A I; Wesseling, C; Hogstedt, C; Wegman, D H

    2016-06-01

    Chronic heat stress and dehydration from strenuous work in hot environments is considered an essential component of the epidemic of chronic kidney disease in Central America. (1) To assess feasibility of providing an intervention modelled on OSHA's Water.Rest.Shade programme (WRS) during sugarcane cutting and (2) to prevent heat stress and dehydration without decreasing productivity. Midway through the 6-month harvest, the intervention introduced WRS practices. A 60-person cutting group was provided water supplied in individual backpacks, mobile shaded rest areas and scheduled rest periods. Ergonomically improved machetes and efficiency strategies were also implemented. Health data (anthropometric, blood, urine, questionnaires) were collected preharvest, preintervention, mid-intervention and at the end of harvest. A subsample participated in focus group discussions. Daily wet bulb globe temperatures (WBGT) were recorded. The employer provided individual production records. Over the harvest WBGT was >26°C from 9:00 onwards reaching average maximum of 29.3±1.7°C, around 13:00. Postintervention self-reported water consumption increased 25%. Symptoms associated with heat stress and with dehydration decreased. Individual daily production increased from 5.1 to a high of 7.3 tons/person/day postintervention. This increase was greater than in other cutting groups at the company. Focus groups reported a positive perception of components of the WRS, and the new machete and cutting programmes. A WRS intervention is feasible in sugarcane fields, and appears to markedly reduce the impact of the heat stress conditions for the workforce. With proper attention to work practices, production can be maintained with less impact on worker health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  2. Identifying Objective Physiological Markers and Modifiable Behaviors for Self-Reported Stress and Mental Health Status Using Wearable Sensors and Mobile Phones: Observational Study.

    Science.gov (United States)

    Sano, Akane; Taylor, Sara; McHill, Andrew W; Phillips, Andrew Jk; Barger, Laura K; Klerman, Elizabeth; Picard, Rosalind

    2018-06-08

    Wearable and mobile devices that capture multimodal data have the potential to identify risk factors for high stress and poor mental health and to provide information to improve health and well-being. We developed new tools that provide objective physiological and behavioral measures using wearable sensors and mobile phones, together with methods that improve their data integrity. The aim of this study was to examine, using machine learning, how accurately these measures could identify conditions of self-reported high stress and poor mental health and which of the underlying modalities and measures were most accurate in identifying those conditions. We designed and conducted the 1-month SNAPSHOT study that investigated how daily behaviors and social networks influence self-reported stress, mood, and other health or well-being-related factors. We collected over 145,000 hours of data from 201 college students (age: 18-25 years, male:female=1.8:1) at one university, all recruited within self-identified social groups. Each student filled out standardized pre- and postquestionnaires on stress and mental health; during the month, each student completed twice-daily electronic diaries (e-diaries), wore two wrist-based sensors that recorded continuous physical activity and autonomic physiology, and installed an app on their mobile phone that recorded phone usage and geolocation patterns. We developed tools to make data collection more efficient, including data-check systems for sensor and mobile phone data and an e-diary administrative module for study investigators to locate possible errors in the e-diaries and communicate with participants to correct their entries promptly, which reduced the time taken to clean e-diary data by 69%. We constructed features and applied machine learning to the multimodal data to identify factors associated with self-reported poststudy stress and mental health, including behaviors that can be possibly modified by the individual to improve

  3. Computer program for the calculation of stresses in rotary equipment discs; Programas de computo para el calculo de esfuerzos en discos de equipo rotatorio

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez Delgado, Wilson; Kubiak, Janusz; Serrano Romero, Luis Enrique [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    In the preliminary design and diagnosis of rotary machines is very common to utilize simple calculation methods for the mechanical and thermal stresses, dynamic and thermodynamic analysis and flow of fluids in this machines (Gutierrez et al., 1989). The analysis with these methods provides the necessary results for the project initial stage of the machine. Later on, more complex tools are employed to refine the design of some machine components. In the Gutierrez report et al., (1989) 34 programs were developed for the preliminary design and diagnosis of rotating equipment; in this article, one of them is presented in which a method for the analysis of mechanical and thermal stresses is applied in discs of uniform or variable thickness that are normally found in turbomachines and rotary equipment. [Espanol] En el diseno preliminar y diagnostico de maquinas rotatorias es muy comun emplear metodos de calculo sencillos para el analisis de esfuerzos mecanicos y termicos, analisis dinamico y termodinamico y de flujo de fluidos en estas maquinas (Gutierrez et al., 1989). El analisis con estos metodos proporcionan los resultados necesarios para la etapa del proyecto inicial de la maquina. Posteriormente, para refinar el diseno de algunos componentes de la maquina, se aplican las herramientas mas complejas. En el informe de Gutierrez et al., (1989) se desarrollan 34 programas para el diseno preliminar y diagnostico de equipo rotatorio; en este articulo, se presenta uno de ellos, en el que se emplea un metodo para el analisis de esfuerzos mecanicos y termicos en discos de espesor constante o variable que se encuentran comunmente en turbomaquinas y en equipos rotatorios.

  4. Computer program for the calculation of stresses in rotary equipment discs; Programas de computo para el calculo de esfuerzos en discos de equipo rotatorio

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez Delgado, Wilson; Kubiak, Janusz; Serrano Romero, Luis Enrique [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1991-12-31

    In the preliminary design and diagnosis of rotary machines is very common to utilize simple calculation methods for the mechanical and thermal stresses, dynamic and thermodynamic analysis and flow of fluids in this machines (Gutierrez et al., 1989). The analysis with these methods provides the necessary results for the project initial stage of the machine. Later on, more complex tools are employed to refine the design of some machine components. In the Gutierrez report et al., (1989) 34 programs were developed for the preliminary design and diagnosis of rotating equipment; in this article, one of them is presented in which a method for the analysis of mechanical and thermal stresses is applied in discs of uniform or variable thickness that are normally found in turbomachines and rotary equipment. [Espanol] En el diseno preliminar y diagnostico de maquinas rotatorias es muy comun emplear metodos de calculo sencillos para el analisis de esfuerzos mecanicos y termicos, analisis dinamico y termodinamico y de flujo de fluidos en estas maquinas (Gutierrez et al., 1989). El analisis con estos metodos proporcionan los resultados necesarios para la etapa del proyecto inicial de la maquina. Posteriormente, para refinar el diseno de algunos componentes de la maquina, se aplican las herramientas mas complejas. En el informe de Gutierrez et al., (1989) se desarrollan 34 programas para el diseno preliminar y diagnostico de equipo rotatorio; en este articulo, se presenta uno de ellos, en el que se emplea un metodo para el analisis de esfuerzos mecanicos y termicos en discos de espesor constante o variable que se encuentran comunmente en turbomaquinas y en equipos rotatorios.

  5. 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 ...

  6. Hypoxia Stress Modifies Na/K-ATPase, H/K-ATPase, , and Isoform Expression in the Brain of Immune-Challenged Air-Breathing Fish

    Directory of Open Access Journals (Sweden)

    MC Subhash Peter

    2017-11-01

    Full Text Available Fishes are equipped to sense stressful stimuli and are able to respond to environmental stressor such as hypoxia with varying pattern of stress response. The functional attributes of brain to hypoxia stress in relation to ion transport and its interaction during immune challenge have not yet delineated in fish. We, therefore, explored the pattern of ion transporter functions and messenger RNA (mRNA expression of α1-subunit isoforms of Na + /K + -ATPase (NKA in the brain segments, namely, prosencephalon (PC, mesencephalon (MC, and metencephalon (MeC in an obligate air-breathing fish exposed either to hypoxia stress (30 minutes forced immersion in water or challenged with zymosan treatment (25-200 ng g −1 for 24 hours or both. Zymosan that produced nonspecific immune responses evoked differential regulation of NKA, H + /K + -ATPase (HKA, and Na + / NH 4 + - ATPase (NNA in the varied brain segments. On the contrary, hypoxia stress that demanded activation of NKA in PC and MeC showed a reversed NKA activity pattern in MeC of immune-challenged fish. A compromised HKA and NNA regulation during hypoxia stress was found in immune-challenged fish, indicating the role of these brain ion transporters to hypoxia stress and immune challenges. The differential mRNA expression of α1-subunit isoforms of NKA, nkaα1a , nkaα1b , and nkaα1c , in hypoxia-stressed brain showed a shift in its expression pattern during hypoxia stress-immune interaction in PC and MC. Evidence is thus presented for the first time that ion transporters such as HKA and NNA along with NKA act as functional brain markers which respond differentially to both hypoxia stress and immune challenges. Taken together, the data further provide evidence for a differential Na + , K + , H + , and NH 4 + ion signaling that exists in brain neuronal clusters during hypoxia stress-immune interaction as a result of modified regulations of NKA, HKA, and NNA transporter functions and nkaα1 isoform

  7. The comparison of an inexpensive-modified transobturator vaginal tape versus TVT-O procedure for the surgical treatment of female stress urinary incontinence.

    Science.gov (United States)

    Zhang, Yan; Jiang, Min; Tong, Xiao-Wen; Fan, Bo-Zhen; Li, Huai-Fang; Chen, Xin-Liang

    2011-09-01

    To compare the safety and efficacy of an inexpensive-modified transobturator vaginal tape procedure with the transobturator tension-free vaginal tape (TVT-O) procedure for the surgical treatment of female stress urinary incontinence (SUI). Patients with SUI were randomly allocated to either the test group receiving the inexpensive-modified transobturator vaginal tape procedure or the control group receiving the GYNECARE TVT-O procedure. Treatment outcomes and Quality-of-life scores were recorded and analyzed between two groups. A total of 156 patients were enrolled in this trial. Eighty patients underwent the modified transobturator vaginal tape procedure. Among them 75(93.8%) were cured and 5(6.2%) were improved. The rest of the 76 patients underwent the GYNECARE TVT-O procedure with a 92% (70 of 76) cure rate and an 8% (6 of 76) improvement rate. No inefficient or aggravated cases occurred in both groups. The success rates between groups had no significant statistic difference (p > 0.05). The operative time, blood loss, hospital stay, and medical cost were significantly lower in the test group (p < 0.01); the increases in Quality-of-life scores were comparable between groups. The modified transobturator vaginal tape procedure is an efficacious and economic surgical treatment for female SUI. Copyright © 2011. Published by Elsevier B.V.

  8. Retos investigativos en psicología de la salud ocupacional: el estrés laboral / Research challenges in occupational health psychology: work stress

    Directory of Open Access Journals (Sweden)

    Angélica M. Hermosa R.

    2015-09-01

    Full Text Available Resumen El presente artículo tiene como propósito exponer los retos de la investigación en psicología de la salud ocupacional, en particular el estrés en el trabajo, uno de los temas de mayor desarrollo en esta disciplina. El artículo describe los elementos conceptuales y determinantes del estrés en el trabajo, se identifican las dificultades de la investigación en esta área y, se plantean sugerencias metodológicas para enriquecer esta investigación. Los programas de intervención son analizados comparando enfoques, diseños y resultados efectivos. Por último, se proponen directrices para mejorar la investigación en este campo. / Abstract This paper aims to present the challenges of research in occupational health psychology, particularly work stress, which is one of the issues of greatest development in this discipline. This paper describes the key conceptual elements of work stress. Furthermore, the difficulties of research in this field are identified and methodological suggestions are presented for enriching research on this issue. Intervention programs in this area are analyzed comparing approaches, designs and effective results. Finally, guidelines are proposed to improve research in this field.

  9. Chronic Stress and Adolescents' Mental Health : Modifying Effects of Basal Cortisol and Parental Psychiatric History. The TRAILS Study

    NARCIS (Netherlands)

    Zandstra, Anna Roos E.; Hartman, Catharina A.; Nederhof, Esther; van den Heuvel, Edwin R.; Dietrich, Andrea; Hoekstra, Pieter J.; Ormel, Johan

    Large individual differences in adolescent mental health following chronic psychosocial stress suggest moderating factors. We examined two established moderators, basal cortisol and parental psychiatric history, simultaneously. We hypothesized that individuals with high basal cortisol, assumed to

  10. Antagonism of corticotrophin-releasing factor receptors in the fourth ventricle modifies responses to mild but not restraint stress

    OpenAIRE

    Miragaya, Joanna R.; Harris, Ruth B. S.

    2008-01-01

    Repeated restraint stress (RRS; 3 h of restraint on 3 consecutive days) in rodents produces temporary hypophagia, but a long-term downregulation of body weight. The mild stress (MS) of an intraperitoneal injection of saline and housing in a novel room for 2 h also inhibits food intake and weight gain, but the effects are smaller than for RRS. Previous exposure to RRS exaggerates hypophagia, glucocorticoid release, and anxiety-type behavior caused by MS. Here we tested the involvement of brain...

  11. Effect of Activated Flux on the Microstructure, Mechanical Properties, and Residual Stresses of Modified 9Cr-1Mo Steel Weld Joints

    Science.gov (United States)

    Maduraimuthu, V.; Vasudevan, M.; Muthupandi, V.; Bhaduri, A. K.; Jayakumar, T.

    2012-02-01

    A novel variant of tungsten inert gas (TIG) welding called activated-TIG (A-TIG) welding, which uses a thin layer of activated flux coating applied on the joint area prior to welding, is known to enhance the depth of penetration during autogenous TIG welding and overcomes the limitation associated with TIG welding of modified 9Cr-1Mo steels. Therefore, it is necessary to develop a specific activated flux for enhancing the depth of penetration during autogeneous TIG welding of modified 9Cr-1Mo steel. In the current work, activated flux composition is optimized to achieve 6 mm depth of penetration in single-pass TIG welding at minimum heat input possible. Then square butt weld joints are made for 6-mm-thick and 10-mm-thick plates using the optimized flux. The effect of flux on the microstructure, mechanical properties, and residual stresses of the A-TIG weld joint is studied by comparing it with that of the weld joints made by conventional multipass TIG welding process using matching filler wire. Welded microstructure in the A-TIG weld joint is coarser because of the higher peak temperature in A-TIG welding process compared with that of multipass TIG weld joint made by a conventional TIG welding process. Transverse strength properties of the modified 9Cr-1Mo steel weld produced by A-TIG welding exceeded the minimum specified strength values of the base materials. The average toughness values of A-TIG weld joints are lower compared with that of the base metal and multipass weld joints due to the presence of δ-ferrite and inclusions in the weld metal caused by the flux. Compressive residual stresses are observed in the fusion zone of A-TIG weld joint, whereas tensile residual stresses are observed in the multipass TIG weld joint.

  12. Chronic Stress and Adolescents' Mental Health: Modifying Effects of Basal Cortisol and Parental Psychiatric History. The TRAILS Study.

    Science.gov (United States)

    Zandstra, Anna Roos E; Hartman, Catharina A; Nederhof, Esther; van den Heuvel, Edwin R; Dietrich, Andrea; Hoekstra, Pieter J; Ormel, Johan

    2015-08-01

    Large individual differences in adolescent mental health following chronic psychosocial stress suggest moderating factors. We examined two established moderators, basal cortisol and parental psychiatric history, simultaneously. We hypothesized that individuals with high basal cortisol, assumed to indicate high context sensitivity, would show relatively high problem levels following chronic stress, especially in the presence of parental psychiatric history. With Linear Mixed Models, we investigated the hypotheses in 1917 Dutch adolescents (53.2% boys), assessed at ages 11, 13.5, and 16. Low basal cortisol combined with the absence of a parental psychiatric history increased the risk of externalizing but not internalizing problems following chronic stress. Conversely, low basal cortisol combined with a substantial parental psychiatric history increased the risk of internalizing but not externalizing problems following chronic stress. Thus, parental psychiatric history moderated stress- cortisol interactions in predicting psychopathology, but in a different direction than hypothesized. We conclude that the premise that basal cortisol indicates context sensitivity may be too crude. Context sensitivity may not be a general trait but may depend on the nature of the context (e.g., type or duration of stress exposure) and on the outcome of interest (e.g., internalizing vs. externalizing problems). Although consistent across informants, our findings need replication.

  13. Prenatal stress modifies behavior and hypothalamic-pituitary-adrenal function in female guinea pig offspring: effects of timing of prenatal stress and stage of reproductive cycle.

    Science.gov (United States)

    Kapoor, Amita; Matthews, Stephen G

    2008-12-01

    Prenatal stress is associated with altered behavior and hypothalamic-pituitary-adrenal (HPA) axis function postnatally. Recent studies suggest that these outcomes are dependent on the timing of the prenatal stress. The majority of these studies have been carried out in male offspring. We hypothesized that a short period of prenatal stress would result in female offspring that exhibit differences in open-field behavior and HPA axis activity, but the outcome would depend on the timing of the prenatal stress and the stage of the reproductive cycle. Pregnant guinea pigs were exposed to a strobe light during the fetal brain growth spurt [gestational d 50-52 (PS50)] or during the period of rapid brain myelination [gestational d 60-62 (PS60)]. Open-field activity was assessed in juvenile and adult female offspring. HPA axis function was tested in adult offspring. All tests in adulthood were carried out during the estrous and luteal phases of the reproductive cycle to determine the effect of stage on HPA axis programming. Tissues were collected upon completion of the study for analysis by in situ hybridization. PS60 offspring exhibited decreased activity in an open field during the estrous phase of the reproductive cycle compared with control offspring. Both PS50 and PS60 offspring exhibited a lower salivary cortisol response to a stressor, only during the estrous phase. Consistent with the behavioral and endocrine data, PS60 females exhibited lower plasma estradiol levels, reduced ovary weight, and increased glucocorticoid receptor mRNA in the paraventricular nucleus. In conclusion, we have demonstrated that there are effects of prenatal stress on behavior and HPA axis functioning in female offspring but that the outcomes are dependent on the timing of the prenatal stress together with the status of the reproductive cycle.

  14. Trait specific expression profiling of salt stress responsive genes in diverse rice genotypes as determined by modified Significance Analysis of Microarrays

    Directory of Open Access Journals (Sweden)

    Mohammad Rashed Hossain

    2016-05-01

    Full Text Available Stress responsive gene expression is commonly profiled in a comparative manner involving different stress conditions or genotypes with contrasting reputation of tolerance/resistance. In contrast, this research exploited a wide natural variation in terms of taxonomy, origin and salt sensitivity in eight genotypes of rice to identify the trait specific patterns of gene expression under salt stress. Genome wide transcptomic responses were interrogated by the weighted continuous morpho-physiological trait responses using modified Significance Analysis of Microarrays. More number of genes was found to be differentially expressed under salt stressed compared to that of under unstressed conditions. Higher numbers of genes were observed to be differentially expressed for the traits shoot Na+/K+, shoot Na+, root K+, biomass and shoot Cl-, respectively. The results identified around sixty genes to be involved in Na+, K+ and anion homeostasis, transport and transmembrane activity under stressed conditions. Gene Ontology (GO enrichment analysis identified 1.36% (578 genes of the entire transcriptome to be involved in the major molecular functions such as signal transduction (>150 genes, transcription factor (81 genes and translation factor activity (62 genes etc. under salt stress. Chromosomal mapping of the genes suggests that majority of the genes are located on chromosomes 1, 2, 3, 6 & 7. The gene network analysis showed that the transcription factors and translation initiation factors formed the major gene networks and are mostly active in nucleus, cytoplasm and mitochondria whereas the membrane and vesicle bound proteins formed a secondary network active in plasma membrane and vacuoles. The novel genes and the genes with unknown functions thus identified provide picture of a synergistic salinity response representing the potentially fundamental mechanisms that are active in the wide natural genetic background of rice and will be of greater use once

  15. Arbuscular mycorrhizal fungi modify nutrient allocation and composition in wheat (Triticum aestivum L.) subjected to heat-stress

    DEFF Research Database (Denmark)

    Cabral, Carmina; Ravnskov, Sabine; Tringovska, Ivanka

    2016-01-01

    - and micronutrient concentrations in aboveground biomass; evaluation of AM fungal structures in roots and assessment of light-use efficiency of plants. Results AM increased grain number in wheat under heat-stress, and altered nutrient allocation and tiller nutrient composition. Heat increased number of arbuscules...... in wheat root, whereas number of vesicles and total colonization were unaffected. Heat increased photosystem II yield and the electron transfer rate, whereas non-photochemical quenching decreased during the first 2 days of heat-stress. Conclusions Nutrient allocation and –composition in wheat grown under...

  16. Vibration and buckling of orthotropic functionally graded micro-plates on the basis of a re-modified couple stress theory

    Directory of Open Access Journals (Sweden)

    Zihao Yang

    Full Text Available A microstructure-dependent model for the free vibration and buckling analysis of an orthotropic functionally graded micro-plate was proposed on the basis of a re-modified couple stress theory. The macro- and microscopic anisotropy were simultaneously taken into account by introducing two material length scale parameters. The material attributes were assumed to vary continuously through the thickness direction by a power law. The governing equations and corresponding boundary conditions were derived through Hamilton’s principle. The Navier method was used to calculate the natural frequencies and buckling loads of a simply supported micro-plate. The numerical results indicated that the present model predicts higher natural frequencies and critical buckling loads than the classical model, particular when the geometric size of the micro-plates is comparable to the material length scale parameters, i.e., the scale effect is well represented. The scale effect becomes more noticeable as the material length scale parameters increase, the anisotropy weaken or the power law index increases, and vice versa. Keywords: Free vibration, Buckling, Functionally graded materials, Modified couple stress theory, Scale effect

  17. Nutritional support in children under metabolic stress Soporte nutricional en el niño con estrés metabólico

    Directory of Open Access Journals (Sweden)

    María Elsy Sepúlveda Hincapié

    1999-04-01

    Full Text Available A review is presented on metabolic changes that occur in children under stress, and on the organs that are affected by the response to it; also considered are the different resources that are presently available in order to maintain nutrition in these children and to improve their probabilities of recovery. Se hace una revisión acerca de los cambios metabólicos que ocurren en el niño durante el estrés y los órganos que se afectan en su respuesta; se tienen en cuenta además, los diferentes recursos que actualmente se pueden utilizar con el fin de mantener la nutrición del niño durante este tipo de situación, mejorando sus posibilidades de recuperación.

  18. Finite element analysis of the stress distributions in peri-implant bone in modified and standard-threaded dental implants

    Directory of Open Access Journals (Sweden)

    Serkan Dundar

    2016-01-01

    Full Text Available The aim of this study was to examine the stress distributions with three different loads in two different geometric and threaded types of dental implants by finite element analysis. For this purpose, two different implant models, Nobel Replace and Nobel Active (Nobel Biocare, Zurich, Switzerland, which are currently used in clinical cases, were constructed by using ANSYS Workbench 12.1. The stress distributions on components of the implant system under three different static loadings were analysed for the two models. The maximum stress values that occurred in all components were observed in FIII (300 N. The maximum stress values occurred in FIII (300 N when the Nobel Replace implant is used, whereas the lowest ones, in the case of FI (150 N loading in the Nobel Active implant. In all models, the maximum tensions were observed to be in the neck region of the implants. Increasing the connection between the implant and the bone surface may allow more uniform distribution of the forces of the dental implant and may protect the bone around the implant. Thus, the implant could remain in the mouth for longer periods. Variable-thread tapered implants can increase the implant and bone contact.

  19. Genetic polymorphisms in DNA repair and oxidative stress pathways may modify the association between body size and postmenopausal breast cancer

    Czech Academy of Sciences Publication Activity Database

    McCullough, L. E.; Eng, S. M.; Bradshaw, P. T.; Cleveland, R. J.; Steck, S. E.; Terry, M. B.; Shen, J.; Crew, K.D.; Rössner ml., Pavel; Ahn, J.; Ambrosone, Ch.B.; Teitelbaum, S. L.; Neugut, A. I.; Santella, R. M.; Gammon, M. D.

    2015-01-01

    Roč. 25, č. 4 (2015), s. 263-269 ISSN 1047-2797 Institutional support: RVO:68378041 Keywords : breast cancer * body mass index * oxidative stress * DNA repair * Epidemiology Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.335, year: 2015

  20. No effect of melatonin to modify surgical-stress response after major vascular surgery: a randomised placebo-controlled trial

    DEFF Research Database (Denmark)

    Kücükakin, B; Wilhelmsen, M; Lykkesfeldt, Jens

    2010-01-01

    A possible mechanism underlying cardiovascular morbidity after major vascular surgery may be the perioperative ischaemia-reperfusion with excessive oxygen-derived free-radical production and increased levels of circulating inflammatory mediators. We examined the effect of melatonin infusion during...... surgery and oral melatonin treatment for 3 days after surgery on biochemical markers of oxidative and inflammatory stress....

  1. Is the titer of adipokinetic peptides in Leptinotarsa decemlineata fed on genetically modified potatoes increased by oxidative stress?

    Czech Academy of Sciences Publication Activity Database

    Kodrík, Dalibor; Krishnan, Natraj; Habuštová, Oxana

    2007-01-01

    Roč. 28, č. 5, (2007), s. 974-980 ISSN 0196-9781 R&D Projects: GA ČR GA522/05/0151; GA ČR(CZ) GA522/06/1591 Institutional research plan: CEZ:AV0Z50070508 Keywords : adipokinetic hormone * oxidative stress * GMO Subject RIV: ED - Physiology Impact factor: 2.368, year: 2007

  2. Habitat pollution and thermal regime modify molecular stress responses to elevated temperature in freshwater mussels (Anodonta anatina: Unionidae)

    International Nuclear Information System (INIS)

    Falfushynska, H.; Gnatyshyna, L.; Yurchak, I.; Ivanina, A.; Stoliar, O.; Sokolova, I.

    2014-01-01

    Elevated temperature and pollution are common stressors in freshwater ecosystems. We study cellular stress response to acute warming in Anodonta anatina (Unionidae) from sites with different thermal regimes and pollution levels: a pristine area and an agriculturally polluted site with normal temperature regimes (F and A, respectively) and a polluted site with elevated temperature (N) from the cooling pond of an electrical power plant. Animals were exposed to different temperatures for 14 days and stress response markers were measured in gills, digestive gland and hemocytes. Mussels from site N and A had elevated background levels of lactate dehydrogenase activity indicating higher reliance on anaerobic metabolism for ATP production and/or redox maintenance. Exposure to 25 °C and 30 °C induced oxidative stress (indicated by elevated levels of lipid peroxidation products) in digestive gland and gills of mussels from A and F sites, while in mussels from N sites elevated oxidative stress was only apparent at 30 °C. Temperature-induced changes in levels of antioxidants (superoxide dismutase, metallothioneins and glutathione) were tissue- and population-specific. Acute warming led to destabilization of lysosomal membranes and increased frequencies of nuclear lesions in mussels from F and A sites but not in their counterparts from N site. Elevated temperature led to an increase in the frequency of micronuclei in hemocytes in mussels from F and A sites at 25 °C and 30 °C and in mussels from N site at 30 °C. The mussels from N site also demonstrated better survival at elevated temperature (30 °C) than their counterparts from the F and A sites. Taken together, these data indicate that long-term acclimation and/or adaptation of A. anatina to elevated temperatures result in increased thermotolerance and alleviate stress response to moderate temperature rise. In contrast, extreme warming (30 °C) is harmful to mussels from all populations indicating limit to this induced

  3. Habitat pollution and thermal regime modify molecular stress responses to elevated temperature in freshwater mussels (Anodonta anatina: Unionidae)

    Energy Technology Data Exchange (ETDEWEB)

    Falfushynska, H.; Gnatyshyna, L.; Yurchak, I. [Research Laboratory of Comparative Biochemistry and Molecular Biology, Ternopil National Pedagogical University, Kryvonosa Str 2, 46027 Ternopil (Ukraine); Ivanina, A. [Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 (United States); Stoliar, O. [Research Laboratory of Comparative Biochemistry and Molecular Biology, Ternopil National Pedagogical University, Kryvonosa Str 2, 46027 Ternopil (Ukraine); Sokolova, I., E-mail: isokolov@uncc.edu [Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 (United States)

    2014-12-01

    Elevated temperature and pollution are common stressors in freshwater ecosystems. We study cellular stress response to acute warming in Anodonta anatina (Unionidae) from sites with different thermal regimes and pollution levels: a pristine area and an agriculturally polluted site with normal temperature regimes (F and A, respectively) and a polluted site with elevated temperature (N) from the cooling pond of an electrical power plant. Animals were exposed to different temperatures for 14 days and stress response markers were measured in gills, digestive gland and hemocytes. Mussels from site N and A had elevated background levels of lactate dehydrogenase activity indicating higher reliance on anaerobic metabolism for ATP production and/or redox maintenance. Exposure to 25 °C and 30 °C induced oxidative stress (indicated by elevated levels of lipid peroxidation products) in digestive gland and gills of mussels from A and F sites, while in mussels from N sites elevated oxidative stress was only apparent at 30 °C. Temperature-induced changes in levels of antioxidants (superoxide dismutase, metallothioneins and glutathione) were tissue- and population-specific. Acute warming led to destabilization of lysosomal membranes and increased frequencies of nuclear lesions in mussels from F and A sites but not in their counterparts from N site. Elevated temperature led to an increase in the frequency of micronuclei in hemocytes in mussels from F and A sites at 25 °C and 30 °C and in mussels from N site at 30 °C. The mussels from N site also demonstrated better survival at elevated temperature (30 °C) than their counterparts from the F and A sites. Taken together, these data indicate that long-term acclimation and/or adaptation of A. anatina to elevated temperatures result in increased thermotolerance and alleviate stress response to moderate temperature rise. In contrast, extreme warming (30 °C) is harmful to mussels from all populations indicating limit to this induced

  4. Dietary antioxidant and anti-inflammatory intake modifies the effect of cadmium exposure on markers of systemic inflammation and oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Colacino, Justin A.; Arthur, Anna E.; Ferguson, Kelly K.; Rozek, Laura S., E-mail: rozekl@umich.edu

    2014-05-01

    Chronic cadmium exposure may cause disease through induction of systemic oxidative stress and inflammation. Factors that mitigate cadmium toxicity and could serve as interventions in exposed populations have not been well characterized. We used data from the 2003–2010 National Health and Nutrition Examination Survey to quantify diet's role in modifying associations between cadmium exposure and oxidative stress and inflammation. We created a composite antioxidant and anti-inflammatory diet score (ADS) by ranking participants by quintile of intake across a panel of 19 nutrients. We identified associations and effect modification between ADS, urinary cadmium, and markers of oxidative stress and inflammation by multiple linear regression. An interquartile range increase in urinary cadmium was associated with a 47.5%, 8.8%, and 3.7% increase in C-reactive protein (CRP), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP), respectively. An interquartile range increase in ADS was associated with an 7.4%, 3.3%, 5.2%, and 2.5% decrease in CRP, GGT, ALP, and total white blood cell count respectively, and a 3.0% increase in serum bilirubin. ADS significantly attenuated the association between cadmium exposure, CRP and ALP. Dietary interventions may provide a route to reduce the impact of cadmium toxicity on the population level. - Highlights: • Cadmium may cause chronic disease through oxidative stress or inflammation. • We developed a score to quantify dietary antioxidant and anti-inflammatory intake. • Cadmium was associated with markers of oxidative stress and inflammation. • Antioxidant and anti-inflammatory intake mitigated the effects of cadmium exposure. • Dietary interventions may be effective against chronic cadmium toxicity.

  5. The enhancement of tolerance to salt and cold stresses by modifying the redox state and salicylic acid content via the cytosolic malate dehydrogenase gene in transgenic apple plants.

    Science.gov (United States)

    Wang, Qing-Jie; Sun, Hong; Dong, Qing-Long; Sun, Tian-Yu; Jin, Zhong-Xin; Hao, Yu-Jin; Yao, Yu-Xin

    2016-10-01

    In this study, we characterized the role of an apple cytosolic malate dehydrogenase gene (MdcyMDH) in the tolerance to salt and cold stresses and investigated its regulation mechanism in stress tolerance. The MdcyMDH transcript was induced by mild cold and salt treatments, and MdcyMDH-overexpressing apple plants possessed improved cold and salt tolerance compared to wild-type (WT) plants. A digital gene expression tag profiling analysis revealed that MdcyMDH overexpression largely altered some biological processes, including hormone signal transduction, photosynthesis, citrate cycle and oxidation-reduction. Further experiments verified that MdcyMDH overexpression modified the mitochondrial and chloroplast metabolisms and elevated the level of reducing power, primarily caused by increased ascorbate and glutathione, as well as the increased ratios of ascorbate/dehydroascorbate and glutathione/glutathione disulphide, under normal and especially stress conditions. Concurrently, the transgenic plants produced a high H2 O2 content, but a low O2·- production rate was observed compared to the WT plants. On the other hand, the transgenic plants accumulated more free and total salicylic acid (SA) than the WT plants under normal and stress conditions. Taken together, MdcyMDH conferred the transgenic apple plants a higher stress tolerance by producing more reductive redox states and increasing the SA level; MdcyMDH could serve as a target gene to genetically engineer salt- and cold-tolerant trees. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  6. Dietary antioxidant and anti-inflammatory intake modifies the effect of cadmium exposure on markers of systemic inflammation and oxidative stress

    International Nuclear Information System (INIS)

    Colacino, Justin A.; Arthur, Anna E.; Ferguson, Kelly K.; Rozek, Laura S.

    2014-01-01

    Chronic cadmium exposure may cause disease through induction of systemic oxidative stress and inflammation. Factors that mitigate cadmium toxicity and could serve as interventions in exposed populations have not been well characterized. We used data from the 2003–2010 National Health and Nutrition Examination Survey to quantify diet's role in modifying associations between cadmium exposure and oxidative stress and inflammation. We created a composite antioxidant and anti-inflammatory diet score (ADS) by ranking participants by quintile of intake across a panel of 19 nutrients. We identified associations and effect modification between ADS, urinary cadmium, and markers of oxidative stress and inflammation by multiple linear regression. An interquartile range increase in urinary cadmium was associated with a 47.5%, 8.8%, and 3.7% increase in C-reactive protein (CRP), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP), respectively. An interquartile range increase in ADS was associated with an 7.4%, 3.3%, 5.2%, and 2.5% decrease in CRP, GGT, ALP, and total white blood cell count respectively, and a 3.0% increase in serum bilirubin. ADS significantly attenuated the association between cadmium exposure, CRP and ALP. Dietary interventions may provide a route to reduce the impact of cadmium toxicity on the population level. - Highlights: • Cadmium may cause chronic disease through oxidative stress or inflammation. • We developed a score to quantify dietary antioxidant and anti-inflammatory intake. • Cadmium was associated with markers of oxidative stress and inflammation. • Antioxidant and anti-inflammatory intake mitigated the effects of cadmium exposure. • Dietary interventions may be effective against chronic cadmium toxicity

  7. Does a modified mindfulness-based cognitive therapy (MBCT) course have the potential to reduce stress and burnout in NHS GPs? Feasibility study.

    Science.gov (United States)

    Hamilton-West, Kate; Pellatt-Higgins, Tracy; Pillai, Neil

    2018-04-19

    AimTo explore, for the first time, whether a modified mindfulness-based cognitive therapy (MBCT) course has the potential to reduce stress and burnout among National Health Service (NHS) General Practitioners. There is a crisis of low morale among NHS GPs, with most describing their workload as 'unmanageable'. MBCT has been demonstrated to improve stress and burnout in other populations, but has not yet been evaluated in a cohort of NHS GPs. NHS GPs in South East England (n=22) attended a modified version of the MBCT course approved by National Institute for Health and Care Excellence for prevention of depressive relapse. This comprised eight weekly 2-h sessions with homework (mindfulness practice) between sessions. Participants completed the Maslach Burnout Inventory (MBI) and Perceived Stress Scale (PSS) before (baseline) and then again one month (T2) and three months (T3) after attending the course. We also obtained qualitative data on participants' experiences of the course.FindingsCompliance with the intervention was very high. All GPs attended at least six sessions and all completed baseline questionnaires. At T2, data were obtained from 21 participants (95%); PSS scores were significantly lower than at baseline (P<0.001), as were MBI emotional exhaustion (P<0.001) and depersonalization scores (P=0.0421). At T3 we obtained data for 13 participants (59%); PSS scores and MBI emotional exhaustion scores were significantly lower (P<0.001; P=0.0024, respectively) and personal accomplishment scores were significantly higher (P<0.001) than at baseline. Participants reported that the course helped them to manage work pressures, feel more relaxed, enjoy their work and experience greater empathy and compassion (for self, colleagues and patients). Findings of this preliminary evaluation are promising. Further research is needed to evaluate this approach within a larger randomized-controlled trial.

  8. High glucose modifies transient receptor potential canonical type 6 channels via increased oxidative stress and syndecan-4 in human podocytes

    DEFF Research Database (Denmark)

    Thilo, Florian; Lee, Marlene; Xia, Shengqiang

    2014-01-01

    oxidative stress and syndecan-4 (SDC-4) in human podocytes. Human podocytes were exposed to control conditions (5.6 mmol/L D-glucose), high glucose (30 mmol/L D-glucose or L-glucose), 100 μmol/L peroxynitrite, or high glucose and the superoxide dismutase mimetic tempol (100 μmol/L). TRPC6 and SDC-4...... transcripts and protein expression were measured using RT-PCR and in-cell Western assay. Intracellular reactive oxygen species (ROS) and cytosolic calcium were measured using fluorescent dye techniques. High D-glucose increased TRPC6 transcripts to 8.66±4.08 (p....44±0.07 (poxidative stress using peroxynitrite significantly increased TRPC6 transcripts to 4.29±1.26 (p

  9. No effect on oxidative stress biomarkers by modified intakes of polyunsaturated fatty acids or vegetables and fruit

    DEFF Research Database (Denmark)

    Freese, R; Dragsted, L O; Loft, S

    2007-01-01

    Diet may both increase and decrease oxidative stress in the body. We compared the effects of four strictly controlled isocaloric diets with different intakes of polyunsaturated fatty acids (PUFA, 11 or 3% of energy) and vegetables and fruit (total amount of vegetables and fruit 516 or 1059 g/10 MJ......) on markers associated with oxidative stress in 77 healthy volunteers (19-52 years). Plasma protein carbonyls (2-aminoadipic semialdehyde residues) and whole-body DNA and nucleotide oxidation (urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine excretion) tended to decrease in all treatment groups with no differences...... between the diets. The diets did not differ in their effects on red blood cell antioxidative enzyme activities, either. The results suggest that in healthy volunteers with adequate nutrient intakes, 6-week diets differing markedly in the amount of PUFA or vegetables and fruit do not differ...

  10. Crack onset assessment near the sharp material inclusion tip by means of modified maximum tangential stress criterion

    Czech Academy of Sciences Publication Activity Database

    Krepl, Ondřej; Klusák, Jan

    2017-01-01

    Roč. 11, č. 42 (2017), s. 66-73 ISSN 1971-8993 R&D Projects: GA MŠk(CZ) LQ1601; GA ČR(CZ) GA16-18702S Institutional support: RVO:68081723 Keywords : Generalized fracture mechanics * Sharp material inclusion * Singular and non-singular stress terms Subject RIV: JL - Materials Fatigue, Friction Mechanics OBOR OECD: Audio engineering, reliability analysis

  11. Beta-carotene reduces oxidative stress, improves glutathione metabolism and modifies antioxidant defense systems in lead-exposed workers

    International Nuclear Information System (INIS)

    Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Janusz; Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa

    2014-01-01

    The aim of this study was to determine whether beta-carotene administration reduces oxidative stress and influences antioxidant, mainly glutathione-related, defense systems in workers chronically exposed to lead. The population consisted of two randomly divided groups of healthy male volunteers exposed to lead. Workers in the first group (reference group) were not administered any antioxidants, while workers in the second group (CAR group) were treated orally with 10 mg of beta-carotene once a day for 12 weeks. Biochemical analysis included measuring markers of lead-exposure and oxidative stress in addition to the levels and activities of selected antioxidants. After treatment, levels of malondialdehyde, lipid hydroperoxides and lipofuscin significantly decreased compared with the reference group. However, the level of glutathione significantly increased compared with the baseline. Treatment with beta-carotene also resulted in significantly decreased glutathione peroxidase activity compared with the reference group, while the activities of other glutathione-related enzymes and of superoxide dismutase were not significantly changed. However, the activities of glucose-6-phosphate dehydrogenase and catalase, as well as the level of alpha-tocopherol, were significantly higher after treatment compared with the baseline. Despite controversy over the antioxidant properties of beta-carotene in vivo, our findings showed reduced oxidative stress after beta-carotene supplementation in chronic lead poisoning. - Highlights: • Beta-carotene reduces oxidative stress in lead-exposed workers. • Beta-carotene elevates glutathione level in lead-exposed workers. • Beta-carotene administration could be beneficial in lead poisoning

  12. Beta-carotene reduces oxidative stress, improves glutathione metabolism and modifies antioxidant defense systems in lead-exposed workers

    Energy Technology Data Exchange (ETDEWEB)

    Kasperczyk, Sławomir, E-mail: kaslav@mp.pl [Dept. of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Dobrakowski, Michał [Dept. of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Kasperczyk, Janusz [Dept. of Environmental Medicine and Epidemiology, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa [Dept. of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland)

    2014-10-01

    The aim of this study was to determine whether beta-carotene administration reduces oxidative stress and influences antioxidant, mainly glutathione-related, defense systems in workers chronically exposed to lead. The population consisted of two randomly divided groups of healthy male volunteers exposed to lead. Workers in the first group (reference group) were not administered any antioxidants, while workers in the second group (CAR group) were treated orally with 10 mg of beta-carotene once a day for 12 weeks. Biochemical analysis included measuring markers of lead-exposure and oxidative stress in addition to the levels and activities of selected antioxidants. After treatment, levels of malondialdehyde, lipid hydroperoxides and lipofuscin significantly decreased compared with the reference group. However, the level of glutathione significantly increased compared with the baseline. Treatment with beta-carotene also resulted in significantly decreased glutathione peroxidase activity compared with the reference group, while the activities of other glutathione-related enzymes and of superoxide dismutase were not significantly changed. However, the activities of glucose-6-phosphate dehydrogenase and catalase, as well as the level of alpha-tocopherol, were significantly higher after treatment compared with the baseline. Despite controversy over the antioxidant properties of beta-carotene in vivo, our findings showed reduced oxidative stress after beta-carotene supplementation in chronic lead poisoning. - Highlights: • Beta-carotene reduces oxidative stress in lead-exposed workers. • Beta-carotene elevates glutathione level in lead-exposed workers. • Beta-carotene administration could be beneficial in lead poisoning.

  13. Modified Feddes type stress reduction function for modeling root water uptake: Accounting for limited aeration and low water potential

    Science.gov (United States)

    Peters, Andre; Durner, Wolfgang; Iden, Sascha C.

    2017-04-01

    Modeling water flow in the soil-plant-atmosphere continuum with the Richards equation requires a model for the sink term describing water uptake by plant roots. Despite recent progress in developing process-based models of water uptake by plant roots and water flow in aboveground parts of vegetation, effective models of root water uptake are widely applied and necessary for large-scale applications. Modeling root water uptake consists of three steps, (i) specification of the spatial distribution of potential uptake, (ii) reduction of uptake due to various stress sources, and (iii) enhancement of uptake in part of the simulation domain to describe compensation. We discuss the conceptual shortcomings of the frequently used root water uptake model of Feddes and suggest a simple but effective improvement of the model. The improved model parametrizes water stress in wet soil by a reduction scheme which is formulated as function of air content where water stress due to low soil water potential is described by the original approach of Feddes. The improved model is physically more consistent than Feddes' model because water uptake in wet soil is limited by aeration which is a function of water content. The suggested modification is particularly relevant for simulations in heterogeneous soils, because stress parameters are uniquely defined for the entire simulation domain, irrespective of soil texture. Numerical simulations of water flow and root water uptake in homogeneous and stochastic heterogeneous soils illustrate the effect of the new model on root water uptake and actual transpiration. For homogeneous fine-textured soils, root water uptake never achieves its potential rate. In stochastic heterogeneous soil, water uptake is more pronounced at the interfaces between fine and coarse regions which has potential implications for plant growth, nutrient uptake and depletion.

  14. The Urban Environment Can Modify Drought Stress of Small-Leaved Lime (Tilia cordata Mill. and Black Locust (Robinia pseudoacacia L.

    Directory of Open Access Journals (Sweden)

    Astrid Moser

    2016-03-01

    Full Text Available The urban environment characterized by various stresses poses challenges to trees. In particular, water deficits and high temperatures can cause immense drought stress to urban trees, resulting in reduced growth and die-off. Drought-tolerant species are expected to be resilient to these conditions and are therefore advantageous over other, more susceptible species. However, the drought tolerance of urban trees in relation to the specific growth conditions in urban areas remains poorly researched. This study aimed to analyze the annual growth and drought tolerance of two common urban tree species, namely small-leaved lime (Tilia cordata Mill. (T. cordata and black locust (Robinia pseudoacacia L. (R. pseudoacacia, in two cities in southern Germany in relation to their urban growing conditions. Marked growth reductions during drought periods and subsequent fast recovery were found for R. pseudoacacia, whereas T. cordata exhibited continued reduced growth after a drought event, although these results were highly specific to the analyzed city. We further show that individual tree characteristics and environmental conditions significantly influence the growth of urban trees. Canopy openness and other aspects of the surrounding environment (water supply and open surface area of the tree pit, tree size, and tree species significantly affect urban tree growth and can modify the ability of trees to tolerate the drought stress in urban areas. Sustainable tree planting of well adapted tree species to their urban environment ensures healthy trees providing ecosystem services for a high quality of life in cities.

  15. 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....

  16. 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.

  17. Trolox reduces the effect of ethanol on acetylcholine-induced contractions and oxidative stress in the isolated rabbit duodenum El Trolox reduce el efecto del etanol sobre las contracciones inducidas a la acetilcolina y el estrés oxidativo en duodeno aislado de conejo

    Directory of Open Access Journals (Sweden)

    Diego S. Fagundes

    2011-08-01

    Full Text Available Trolox is a hydrophilic analogue of vitamin E and a free radical scavenger. Ethanol diminishes the amplitude of spontaneous contractions and acetylcholine (ACh-induced contractions in rabbit duodenum. The aim of this work was to study the effect of Trolox on the alterations induced by ethanol on contractility and lipid peroxidation in the duodenum. The duodenal contractility studies in vitro were carried out in an organ bath and the levels of malondialdehyde and 4-hydroxyalkenals (MDA+4-HAD were measured by spectrophotometry. Trolox increased the reduction induced by ethanol on the amplitude of spontaneous contractions in longitudinal muscle but not in circular muscle. Trolox 4 mM decreased the effects of ethanol on ACh-induced contractions and on MDA+4-HDA concentrations. We conclude that Trolox might prevent oxidative stress induced by ethanol in the duodenum.El Trolox es un análogo hidrofílico de la vitamina E y un agente que secuestra radicales libres. El etanol disminuye la amplitud de las contracciones espontáneas y las contracciones inducidas a la acetilcolina en el duodeno de conejo. El objetivo de este trabajo era estudiar el efecto del Trolox en las alteraciones inducidas por el etanol sobre la contractilidad y la peroxidación lipídica en el duodeno. Los estudios de contractilidad duodenal in vitro se realizaron en un baño de órganos y los niveles de MDA+4-HDA se midieron por espectofotometría. El Trolox aumentó la reducción inducida por el etanol sobre la amplitud de las contracciones espontáneas en el músculo longitudinal pero no en el músculo circular de duodeno. El Trolox 4 mM redujo los efectos del etanol sobre las contracciones inducidas a la acetilcolina y sobre las concentraciones de MDA+4-HDA. Se concluye que el Trolox podría prevenir el estrés oxidativo inducido por el etanol en el duodeno.

  18. Serum oxidative stress is increased in patients with post cholecystectomy bile duct injury Aumento del estrés oxidativo en el suero de pacientes con lesiones de vías biliares postcolecistectomía

    Directory of Open Access Journals (Sweden)

    A. G. Miranda-Díaz

    2010-06-01

    Full Text Available Background: post-cholecystectomy bile duct injuries are identified by the onset of jaundice as well as elevated bilirubin and alkaline phosphatase levels during the peri-operative period. It is unknown how serum oxidative stress markers are modified in patients with post-cholecystectomy bile duct injuries. Objective: to determine serum oxidative stress marker levels (lipid peroxidation by-products, nitrites/nitrates and total antioxidant capacity in patients with post-cholecystectomy bile duct injuries. Patients and methods: a prospective, transversal and analytical study was designed with two groups. Group 1: 5 healthy volunteer subjects. Group 2: 52 patients with post-cholecystectomy bile duct injuries (43 female and 9 male. An elective bilio-digestive reconstruction was performed at week 8. The serum oxidative stress marker levels were quantified by colorimetric method. Results: patients with bile duct injuries had a significant increased serum lipid peroxides (malondialdehyde and 4-hydroxy-alkenals and nitric oxide metabolites (nitrites/nitrates levels compared to the control group. In contrast, total antioxidant capacity in patients with bile duct injuries remained similar compared to healthy controls. Conclusions: the results show that oxidative stress is usually associated to bile duct injury.Introducción: las lesiones de las vías biliares postcolecistectomía se establecen por la aparición de ictericia, elevación de las bilirrubinas y de la fosfatasa alcalina durante el periodo perioperatorio. Se desconoce cómo se modifican los marcadores de estrés oxidativo en el suero de los pacientes con lesiones de las vías biliares postcolecistectomía. Objetivo: determinar los marcadores de estrés oxidativo (productos de peroxidación de lípidos, catabolitos del óxido nítrico y capacidad antioxidante total en el suero de pacientes con lesiones de las vías biliares. Pacientes y métodos: se realizó un estudio prospectivo transversal

  19. Ozone modifies the metabolic and endocrine response to glucose: Reproduction of effects with the stress hormone corticosterone.

    Science.gov (United States)

    Thomson, Errol M; Pilon, Shinjini; Guénette, Josée; Williams, Andrew; Holloway, Alison C

    2018-03-01

    Air pollution is associated with increased incidence of metabolic disease (e.g. metabolic syndrome, obesity, diabetes); however, underlying mechanisms are poorly understood. Air pollutants increase the release of stress hormones (human cortisol, rodent corticosterone), which could contribute to metabolic dysregulation. We assessed acute effects of ozone, and stress axis involvement, on glucose tolerance and on the metabolic (triglyceride), endocrine/energy regulation (insulin, glucagon, GLP-1, leptin, ghrelin, corticosterone), and inflammatory/endothelial (TNF, IL-6, VEGF, PAI-1) response to exogenous glucose. Male Fischer-344 rats were exposed to clean air or 0.8 ppm ozone for 4 h in whole body chambers. Hypothalamic-pituitary-adrenal (HPA) axis involvement in ozone effects was tested through subcutaneous administration of the glucocorticoid synthesis inhibitor metyrapone (50 mg/kg body weight), corticosterone (10 mg/kg body weight), or vehicle (40% propylene glycol) prior to exposure. A glucose tolerance test (2 g/kg body weight glucose) was conducted immediately after exposure, with blood samples collected at 0, 30, 60, 90, and 120 min. Ozone exposure impaired glucose tolerance, an effect accompanied by increased plasma triglycerides but no impairment of insulin release. Ozone diminished glucagon, GLP-1, and ghrelin responses to glucose, but did not significantly impact inflammatory/endothelial analytes. Metyrapone reduced corticosterone but increased glucose and triglycerides, complicating evaluation of the impact of glucocorticoid inhibition. However, administration of corticosterone reproduced the profile of ozone effects, supporting a role for the HPA axis. The results show that ozone-dependent changes in glucose tolerance are accompanied by altered metabolic and endocrine responses to glucose challenge that are reproduced by exogenous stress hormone. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  20. Model-based methodology to develop the isochronous stress-strain curves for modified 9Cr steels

    International Nuclear Information System (INIS)

    Kim, Woo Gon; Yin, Song Nan; Kim, Sung Ho; Lee, Chan Bock; Jung, Ik Hee

    2008-01-01

    Since high temperature materials are designed with a target life based on a specified amount of allowable strain and stress, their Isochronous Stress-Strain Curves (ISSC) are needed to avoid an excessive deformation during an intended service life. In this paper, a model-based methodology to develop the isochronous curves for a G91 steel is described. Creep strain-time curves were reviewed for typical high-temperature materials, and Garofalo's model which conforms well to the primary and secondary creep stages was proper for the G91 steel. Procedures to obtain an instantaneous elastic-plastic strain, ε i were given in detail. Also, to accurately determine the P 1 , P 2 and P 3 parameters in the Garofalo's model, a Nonlinear Least Square Fitting (NLSF) method was adopted and useful. The long-term creep curves for the G91 steel can be modeled by the Garofalo's model, and the long-term ISSCs can be developed using the modeled creep curves

  1. The Application of a Modified d-ROMs Test for Measurement of Oxidative Stress and Oxidized High-Density Lipoprotein

    Directory of Open Access Journals (Sweden)

    Fumiaki Ito

    2017-02-01

    Full Text Available Reactive oxygen species (ROS are involved in the initiation and progression of atherosclerosis. ROS-derived hydroperoxides, as an indicator of ROS production, have been measured by using the diacron reactive oxygen metabolites (d-ROMs test, which requires iron-containing transferrin in the reaction mixture. In this study we developed a modified d-ROMs test, termed the Fe-ROMs test, where iron ions were exogenously added to the reaction mixture. This modification is expected to exclude the assay variation that comes from different blood iron levels in individuals. In addition, this Fe-ROMs test was helpful for determining the class of plasma lipoproteins that are hydroperoxidized. Low-density lipoprotein/very low-density lipoprotein (LDL/VLDL and high-density lipoprotein (HDL were purified by use of an LDL/VLDL purification kit and the dextran sulfate-Mg2+ precipitation method, respectively; their hydroperoxide contents were assessed by performing the Fe-ROMs test. The majority of the hydroperoxides were detected only in the HDL fraction, not in the LDL/VLDL. Further detailed analysis of HDLs by size-exclusion high-performance liquid chromatography revealed that the hydroperoxide-containing molecules were small-sized HDLs. Because HDL was shown to be the principal vehicle for the plasma hydroperoxides, this Fe-ROMs test is a beneficial method for the assessment of oxidized-HDL levels. Indeed, Fe-ROMs levels were strongly associated with the levels of oxidized HDL, which were determined by performing the malondialdehyde-modified HDL enzyme immunoassay. In conclusion, the Fe-ROMs test using plasma itself or the HDL fraction after dextran sulfate-Mg2+ precipitation is useful to assess the functionality of HDL, because the oxidation of HDL impairs its antiatherogenic capacity.

  2. Modeling the effect of intermolecular force on the size-dependent pull-in behavior of beam-type NEMS using modified couple stress theory

    Energy Technology Data Exchange (ETDEWEB)

    Beni, Yaghoub Tadi; Karimipour, Iman [Shahrekord University, Shahrekord (Iran, Islamic Republic of); Abadyan, Mohamadreza [Islamic Azad University, Shahrekord (Iran, Islamic Republic of)

    2014-09-15

    Experimental observations reveal that the physical response of nano structures is size-dependent. Herein, modified couple stress theory has been used to study the effect of intermolecular van der Waals force on the size dependent pull-in of nano bridges and nano cantilevers. Three approaches including using differential transformation method, applying numerical method and developing a simple lumped parameter model have been employed to solve the governing equation of the systems. The pull-in parameters i.e. critical tip deflection and instability voltage of the nano structures have been determined. Effect of the van der Waals attraction and the size dependency and the importance of coupling between them on the pull-in performance have been discussed.

  3. Modeling the effect of intermolecular force on the size-dependent pull-in behavior of beam-type NEMS using modified couple stress theory

    International Nuclear Information System (INIS)

    Beni, Yaghoub Tadi; Karimipour, Iman; Abadyan, Mohamadreza

    2014-01-01

    Experimental observations reveal that the physical response of nano structures is size-dependent. Herein, modified couple stress theory has been used to study the effect of intermolecular van der Waals force on the size dependent pull-in of nano bridges and nano cantilevers. Three approaches including using differential transformation method, applying numerical method and developing a simple lumped parameter model have been employed to solve the governing equation of the systems. The pull-in parameters i.e. critical tip deflection and instability voltage of the nano structures have been determined. Effect of the van der Waals attraction and the size dependency and the importance of coupling between them on the pull-in performance have been discussed.

  4. 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.

  5. Potentiation of glucocorticoid release does not modify the long-term effects of a single exposure to immobilization stress.

    Science.gov (United States)

    Dal-Zotto, Silvina; Martí, Octavi; Delgado, Raúl; Armario, Antonio

    2004-12-01

    Previous work has shown that a single exposure of rats to a severe stressor (immobilization, IMO) results, days to weeks later, in a reduced response (desensitization) of the hypothalamic-pituitary-adrenal (HPA) axis to a second exposure to the same stressor. In the present work, we studied the influence of both length of exposure to IMO and circulating levels of corticosterone on the first day on the degree of desensitization of two sets of physiological variables: HPA hormones and food intake. Rats were given SC saline or ACTH administration and then exposed to IMO for 0, 1 or 20 min. Seven days later, all rats were exposed to 20 min IMO. HPA response was followed on both experimental days by repeated blood sampling and food intake was measured on a 24-h basis. Both ACTH administration and IMO activates the HPA axis and IMO reduced food intake for several days. A single previous experience with IMO enhanced the post-IMO return of HPA hormones to basal levels on day 8 and reduced the degree of anorexia. The protective effect of previous IMO on food intake was independent of, whereas that on HPA activation was positively related to, the length of exposure on day 1. Concomitant ACTH administration on day 1 did not modify the observed effects. Long-term protective effects of a single exposure to IMO are observed even with a brief exposure, but they are not potentiated by increasing corticosterone levels during the first exposure.

  6. Solid-state mAbs and ADCs subjected to heat-stress stability conditions can be covalently modified with buffer and excipient molecules.

    Science.gov (United States)

    Valliere-Douglass, John F; Lewis, Patsy; Salas-Solano, Oscar; Jiang, Shan

    2015-02-01

    We report that a unique type of chemical modification occurs on lyophilized proteins. Freeze-dried mAbs and antibody-drug conjugates (ADCs) can be covalently modified with buffer and excipient molecules on the side chains of Glu, Asp, Thr, and Ser amino acids when subjected to temperature stress. The reaction occurs primarily via condensation of common buffers and excipients such as histidine, tris, trehalose and sucrose, with Glu and Asp carboxylates in the primary sequence of proteins. The reaction was also found to proceed through condensation of carboxylate containing buffers such as citrate, with Thr and Ser hydroxyls in the primary sequence of proteins. Based on the mass of the covalent adducts observed on mAbs and ADCs, it is apparent that the reaction produces water as a product and is thus favored in a low moisture environments such as a lyophilized protein cake. Herein, we present the evidence for the covalent modification of proteins drawn from case studies of in-depth characterization of heat-stressed mAbs and ADCs in the solid state. We also demonstrate how common charge variant assays such as imaged capillary isoelectric focusing and mass spectrometry can be used to monitor this specific class of protein modification. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  7. Evaluation of the interfacial shear strength and residual stress of TiAlN coating on ZIRLO™ fuel cladding using a modified shear-lag model approach

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y., E-mail: troy.liu@manchester.ac.uk [Materials Performance Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom); Bhamji, I., E-mail: imran.bhamji@manchester.ac.uk [Materials Performance Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom); Withers, P.J., E-mail: p.j.withers@manchester.ac.uk [Materials Performance Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom); Wolfe, D.E., E-mail: dew125@arl.psu.edu [The Pennsylvania State University, University Park, State College, PA 16801 (United States); Motta, A.T., E-mail: atmnuc@engr.psu.edu [The Pennsylvania State University, University Park, State College, PA 16801 (United States); Preuss, M., E-mail: michael.preuss@manchester.ac.uk [Materials Performance Centre, School of Materials, The University of Manchester, M13 9PL (United Kingdom)

    2015-11-15

    This paper investigates the residual stresses and interfacial shear strength of a TiAlN coating on Zr–Nb–Sn–Fe alloy (ZIRLO™) substrate designed to improve corrosion resistance of fuel cladding used in water-cooled nuclear reactors, both during normal and exceptional conditions, e.g. a loss of coolant event (LOCA). The distribution and maximum value of the interfacial shear strength has been estimated using a modified shear-lag model. The parameters critical to this analysis were determined experimentally. From these input parameters the interfacial shear strength between the TiAlN coating and ZIRLO™ substrate was inferred to be around 120 MPa. It is worth noting that the apparent strength of the coating is high (∼3.4 GPa). However, this is predominantly due to the large compressive residuals stress (3 GPa in compression), which must be overcome for the coating to fail in tension, which happens at a load just 150 MPa in excess of this.

  8. Niveles de estrés en el personal de enfermería de unidades de cuidados paliativos Stress levels on nursing staff of palliative care units

    Directory of Open Access Journals (Sweden)

    Cristina Gómez Cantorna

    2012-06-01

    Full Text Available Mediante este estudio, nos gustaría saber cuál es el nivel de estrés que padecen las enfermeras, que trabajan en unidades de cuidados paliativos. Para ello hemos elegido una muestra de 94 enfermeras del SERGAS (Servicio Galego de Saúde, de las distintas unidades de cuidados paliativos, utilizando un cuestionario de datos sociodemográficos y organizacionales junto con el Maslach Burnout Inventory, como instrumentos evaluatorios. Después del análisis de los datos observamos que el personal de enfermería que trabaja en dichas unidades de cuidados paliativos, no presenta un nivel de estrés tan elevado como el que nosotros planteábamos al principio de nuestro estudio.Through this study, we would like to know what level of stress experienced by nurses working in palliative care units. We have chosen a sample of 94 nurses of SERGAS (Servicio Galego de las Saúde of the different palliative care units, using a questionnaire on demographic and organizational data with the Maslach Burnout Inventory, for assessment tools. After analyzin the dat we note that the nursing staff working in this departament of palliative care, no estres levels as high as we posed at the beginning of our study.

  9. The 2001 January 13th M {W}7.7 and February 13th M {W}6.6 El Salvador Earthquakes: Deformation and Stress Triggering

    Science.gov (United States)

    Hreinsdóttir, S.; Freymueller, J. T.

    2001-12-01

    On the 13th of January 2001, an M {W} 7.7 normal fault earthquake occurred offshore El Salvador. The earthquake occurred in the subducting Cocos plate and was followed by high seismic activity and several earthquakes exceeding magnitude 5. On the 13th of February, an M {W} 6.6 strike slip earthquake occurred in the overriding Caribbean plate, about 75 km NNW from the epicenter of the large January earthquake. Deformation due to these earthquakes was observed at six continuous CORS GPS stations in Central America. In the M {W} 7.7 earthquake about 10 mm displacement was measured at GPS stations in El Salvador and Honduras. A smaller but significant dispacement was also observed at GPS stations in Nicaragua, more then 200 km from the earthquake's epicenter. In the M {W} 6.6 earthquake 41+/- 1 mm displacement in direction N111oE was measured at the GPS station in San Salvador, El Salvador. Other CORS GPS stations were not affected by that earthquake. A postsesmic signal is detectable at the San Salvador GPS station, strongest right after the earthquake and then decays. On average we see 0.3 +/- 0.1 mm/day of SSW motion of the station in the first twenty days following the earthquake. Using seismic and geodetic data, we calculated Coulomb stress changes following the January 13th, M {W} 7.7 earthquake. Of special interest were six 5.4 earthquake that occurred in the overriding Caribean plate. The location and focal mechanism of these earthquakes correlate with areas of calculated increase in static stress thus indicating stress triggering. The thrust events occurred 2 to 20 days after the M {W} 7.7 earthquake, in increasing distance from the M {W} 7.7 event with time.

  10. Relación del desarrollo cognitivo con el clima familiar y el estrés de la crianza Relationship of the cognitive development with the family clime and stress of the childrearing

    Directory of Open Access Journals (Sweden)

    José Ángel Vera Noriega

    2005-12-01

    Full Text Available Se llevo a cabo un estudio con 120 familias en pobreza extrema de las zonas marginales de Hermosillo, Sonora México. Madres de 32 años en promedio respondieron a una escala de funcionamiento familiar, estrés de la crianza y sus niños fueron medidos en desarrollo cognitivo. El objetivo fue evaluar las diferencias significativas entre los tres tipos de familias en su desarrollo cognitivo, el estrés de la crianza y el clima familiar. Se clasificaron las familias en base a la medida de clima familiar con un análisis de conglomerados (clusters. Los resultados indican: a tres tipos de climas, que etiquetamos como, disciplinado, cohesionado y sin orientación; b clima sin orientación se asocia a una percepción negativa del niño y de restricciones por la maternidad y presentan las medias mas bajas de desarrollo cognitivo; c el clima cohesivo se asocia con menos estrés en la madre por la crianza y los puntajes mas alto de desarrollo cognitivo.A study was performed over 120 families located in the marginal areas of Hermosillo, Sonora, Mexico. Mothers whose age averaged 32 years old responded to a scale of family performance and childrearing stress; their children were measured throughout cognitive development. This study was aimed to evaluate significant differences with regards to cognitive development, child-rearing stress and family environment among the three types of family. The families were classified based on a measurement of family environment with a cluster analysis. Consequently, the results indicate the following: a Three different types of environment, which were labeled as disciplined, in harmony and without direction; b the environment without direction becomes associated to a negative perception of the child and motherhood restrictions, resulting with the lowest average of cognitive development, thus; c the cohesive environment becomes associated with a lower level of stress in the mother induced by child-rearing and with the

  11. 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.

  12. Induction of heat shock proteins DnaK, GroEL, and GroES by salt stress in Lactococcus lactis

    DEFF Research Database (Denmark)

    Kilstrup, Mogens; Jacobsen, Susanne; Hammer, Karin

    1997-01-01

    The bacterium Lactococcus lactis has become a model organism in studies of growth physiology and membrane transport, as a result of its simple fermentative metabolism. It is also used as a model for studying the importance of specific genes and functions during lie in excess nutrients, by compari...... the timing during heat stress although at a lower induction level. These data indicate an overlap between the heat shock and salt stress responses in L. lactis......., by comparison of prototrophic wild-type strains and auxotrophic domesticated (daily) strains. In a study of the capacity of domesticated strains to perform directed responses toward various stress conditions, we have analyzed the heat and salt stress response in the established L,. lactis subsp. cremoris...... laboratory strain MG1363, which was originally derived from a dairy strain, After two-dimensional separation of proteins, the DnaK, GroEL, and GroES heat shock proteins, the HrcA (Orf1) heat shack repressor, and the glycolytic enzymes pyruvate kinase, glyceral-dehyde-3-phosphate dehydrogenase...

  13. Isoflavone Malonyltransferases GmIMaT1 and GmIMaT3 Differently Modify Isoflavone Glucosides in Soybean (Glycine max under Various Stresses

    Directory of Open Access Journals (Sweden)

    Muhammad Z. Ahmad

    2017-05-01

    Full Text Available Malonylated isoflavones are the major forms of isoflavonoids in soybean plants, the genes responsible for their biosyntheses are not well understood, nor their physiological functions. Here we report a new benzylalcohol O-acetyltransferase, anthocyanin O-hydroxycinnamoyltransferase, anthranilate N-hydroxycinnamoyl/benzoyltransferase, deacetylvindoline 4-O-acetyltransferase (BAHD family isoflavone glucoside malonyltransferase GmIMaT1, and GmIMaT3, which is allelic to the previously characterized GmMT7 and GmIF7MaT. Biochemical studies showed that recombinant GmIMaT1 and GmIMaT3 enzymes used malonyl-CoA and several isoflavone 7-O-glucosides as substrates. The Km values of GmIMaT1 for glycitin, genistin, and daidzin were 13.11, 23.04, and 36.28 μM, respectively, while these of GmIMaT3 were 12.94, 26.67, and 30.12 μM, respectively. Transgenic hairy roots overexpressing both GmIMaTs had increased levels of malonyldaidzin and malonylgenistin, and contents of daidzin and glycitin increased only in GmIMaT1-overexpression lines. The increased daidzein and genistein contents were detected only in GmIMaT3-overexpression lines. Knockdown of GmIMaT1 and GmIMaT3 reduced malonyldaidzin and malonylgenistin contents, and affected other isoflavonoids differently. GmIMaT1 is primarily localized to the endoplasmic reticulum while GmIMaT3 is primarily in the cytosol. By examining their transcript changes corresponding to the altered isoflavone metabolic profiles under various environmental and hormonal stresses, we probed the possible functions of GmIMaTs. Two GmIMaTs displayed distinct tissue expression patterns and respond differently to various factors in modifying isoflavone 7-O-glucosides under various stresses.

  14. Ischemia-modified albümin and malondialdehyde levels in patients with overt and subclinical hyperthyroidism: effects of treatment on oxidative stress.

    Science.gov (United States)

    Erem, Cihangir; Suleyman, Akile Karacin; Civan, Nadim; Mentese, Ahmet; Nuhoglu, İrfan; Uzun, Aysegul; Ersoz, Halil Onder; Deger, Orhan

    2015-01-01

    The main purpose of this study was to evaluate the levels of ischemia-modified albumin (IMA) and malondialdehyde (MDA) in patients with OHyper and SHyper, to assess the effects of antithyroid drug (ATD) therapy on the oxidative stress (OS) parameters. Forty-five untreated patients with overt hyperthyroidism (OHyper), 20 untreated patients with subclinical hyperthyroidism (SHyper) and 30 age-and sex-matched healthy controls were prospectively included in the study. Biochemical and hormonal parameters were evaluated in all patients before and after treatment. Compared with the control subjects, the levels of MDA, glucose and TG were significantly increased in patients with SHyper (p<0.05), whereas LDL-C levels were significantly decreased (p<0.01). Patients with OHyper showed significantly elevated MDA and glucose levels (p<0.001) and significantly decreased LDL-C and HDL-C levels compared with the controls (p<0.01). In patients with Graves' disease, serum TSH levels were inversely correlated with plasma MDA levels (r: -0.42, p<0.05). Plasma MDA levels significantly decreased and levels of TC, LDL-C and HDL-C significantly increased in the groups of OHyper and SHyper after treatment. Serum IMA levels did not significantly change at baseline and with the therapy in all subjects. In conclusion, increased MDA levels in both patient groups represent increased lipid peroxidation which might play an important role in the pathogenesis of the atherosclerosis in these patients. Increased oxidative stress in patients with SHyper and OHyper could be improved by ATD therapy. Also, MDA can be used as a reliable marker of OS and oxidative damage, while IMA is considered to be inappropriate.

  15. Large deformation of uniaxially loaded slender microbeams on the basis of modified couple stress theory: Analytical solution and Galerkin-based method

    Science.gov (United States)

    Kiani, Keivan

    2017-09-01

    Large deformation regime of micro-scale slender beam-like structures subjected to axially pointed loads is of high interest to nanotechnologists and applied mechanics community. Herein, size-dependent nonlinear governing equations are derived by employing modified couple stress theory. Under various boundary conditions, analytical relations between axially applied loads and deformations are presented. Additionally, a novel Galerkin-based assumed mode method (AMM) is established to solve the highly nonlinear equations. In some particular cases, the predicted results by the analytical approach are also checked with those of AMM and a reasonably good agreement is reported. Subsequently, the key role of the material length scale on the load-deformation of microbeams is discussed and the deficiencies of the classical elasticity theory in predicting such a crucial mechanical behavior are explained in some detail. The influences of slenderness ratio and thickness of the microbeam on the obtained results are also examined. The present work could be considered as a pivotal step in better realizing the postbuckling behavior of nano-/micro- electro-mechanical systems consist of microbeams.

  16. Zymosan-induced immune challenge modifies the stress response of hypoxic air-breathing fish (Anabas testudineus Bloch): Evidence for reversed patterns of cortisol and thyroid hormone interaction, differential ion transporter functions and non-specific immune response.

    Science.gov (United States)

    Simi, S; Peter, Valsa S; Peter, M C Subhash

    2017-09-15

    Fishes have evolved physiological mechanisms to exhibit stress response, where hormonal signals interact with an array of ion transporters and regulate homeostasis. As major ion transport regulators in fish, cortisol and thyroid hormones have been shown to interact and fine-tune the stress response. Likewise, in fishes many interactions have been identified between stress and immune components, but the physiological basis of such interaction has not yet delineated particularly in air-breathing fish. We, therefore, investigated the responses of thyroid hormones and cortisol, ion transporter functions and non-specific immune response of an obligate air-breathing fish Anabas testudineus Bloch to zymosan treatment or hypoxia stress or both, to understand how immune challenge modifies the pattern of stress response in this fish. Induction of experimental peritonitis in these fish by zymosan treatment (200ngg -1 ) for 24h produced rise in respiratory burst and lysozomal activities in head kidney phagocytes. In contrast, hypoxia stress for 30min in immune-challenged fish reversed these non-specific responses of head kidney phagocytes. The decline in plasma cortisol in zymosan-treated fish and its further suppression by hypoxia stress indicate that immune challenge suppresses the cortisol-driven stress response of this fish. Likewise, the decline in plasma T 3 and T 4 after zymosan-treatment and the rise in plasma T 4 after hypoxia stress in immune-challenged fish indicate a critical role for thyroid hormone in immune-stress response due to its differential sensitivity to both immune and stress challenges. Further, analysis of the activity pattern of ion-dependent ATPases viz. Na + /K + -ATPase, H + /K + -ATPase and Na + /NH 4 + -ATPase indicates a functional interaction of ion transport system with the immune response as evident in its differential and spatial modifications after hypoxia stress in immune-challenged fish. The immune-challenge that produced differential

  17. In-situ studies of the TGO growth stresses and the martensitic transformation in the B2 phase in commercial Pt-modified NiAl and NiCoCrAlY bond coat alloys

    Energy Technology Data Exchange (ETDEWEB)

    Hovis, D.; Hu, L.; Reddy, A.; Heuer, A.H. [Dept. of Materials Science and Engineering, Case Western Reserve Univ., Cleveland, OH (United States); Paulikas, A.P.; Veal, B.W. [Materials Science Div., Argonne National Lab., Argonne, IL (United States)

    2007-12-15

    Oxide growth stresses were measured in situ at 1100 C on commercial Pt-modified NiAl and NiCoCrAlY bond coat alloys using synchrotron X-rays. Measurements were taken on samples that had no preoxidation, as well as on samples that had experienced 24 one-hour thermal exposures at 1150 C, a condition known to induce rumpling in the Pt-modified NiAl alloy, but not in the NiCoCrAlY alloy. The NiCoCrAlY alloy showed continuous stress relaxation under all conditions, whereas the Pt-modified NiAl alloys would typically stabilize at a fixed (often non-zero) stress suggesting a higher creep strength in the 'Thermally Grown Oxide' on the latter alloy, though the precise behavior was dependent on initial surface preparation. The formation of martensite in the Pt-modified NiAl alloys was also observed upon cooling and occurred at temperatures below 200 C for all of the samples observed. Based on existing models, this M{sub s} temperature is too low to account for the rumpling observed in these alloys. (orig.)

  18. Study of the evolution of the seismic cycle of stress and strain associated to the El Salvador Fault Zone

    OpenAIRE

    Staller Vázquez, Alejandra

    2011-01-01

    • Central America: – Regional studies in Central America (Seismic Hazard). – El Salvador Fault Zone (ESFZ). – Aguacaliente‐Navarro Fault Zone (ANFZ), Central Valley of Costa Rica. – Haiti (seismic hazard) • Spain: – Regional‐Nacional studies of seismic hazards (applications to building codes, eurocode, emergency plans, etc.) – Betic range zone, south of Spain. – Ibero‐Maghrebi region (collision zone)

  19. Análisis de la respuesta mecánica de recubrimientos elaborados mediante proyección térmica por plasma usando la medición de esfuerzos residuales y el método de elementos finitos a escala estructural: efecto de la red de poros Mechanical responses of plasma sprayed coatings from residual stress measurements and finite element analysis: effect of the pore network architecture

    Directory of Open Access Journals (Sweden)

    Claudia Constanza Palacio Espinosa

    2011-12-01

    Full Text Available En el presente trabajo se estudia la respuesta mecánica de recubrimientos elaborados mediante proyección térmica por plasma ante la presencia de esfuerzos residuales y campos de esfuerzos generados por deformaciones. Para lograr este propósito, se midieron los esfuerzos residuales durante el proceso de elaboración de recubrimientos de TiO2-Cu y se evaluó el efecto de la red de poros en la estructura de la capa obtenida a partir de imágenes de alta resolución de Microscopía Electrónica de Barrido (MEB obtenidas de los recubrimientos de Al2O3-13TiO2, las cuales fueron posteriormente procesadas y discretizadas para su análisis mediante el Método de Elementos Finitos (MEF. Algunos parámetros operacionales empleados para elaborar los recubrimientos, tales como el flujo de gases y la corriente eléctrica, necesarios para formar el plasma, mostraron tener influencia en el contenido de poros, densidad de grietas y orientación de las mismas y en la magnitud de los esfuerzos residuales provocados. Los esfuerzos residuales determinados a partir de mediciones de deflexión durante la elaboración de los recubrimientos de TiO2-Cu, permitieron identificar su naturaleza, mientras que las simulaciones numéricas mostraron la gran influencia de la red de poros sobre el campo de esfuerzos de los recubrimientos de Al2O3-13TiO2. Del mismo modo, mediante MEF se evaluaron otras composiciones teóricas a través de la modificación de las propiedades mecánicas intrínsecas de las fases constituyentes. Para los casos considerados, las simulaciones mostraron la pobre influencia que tiene la presencia de los constituyentes secundarios en el campo de esfuerzos de los recubrimientos.This study aims a better understanding residual stress and stress field within composite plasma sprayed coatings submitted to strains. In order to reach out this objective, residual stress techniques can be implemented for measurements during elaboration of coatings and finite

  20. A change in coral extension rates and stable isotopes after El Niño-induced coral bleaching and regional stress events

    Science.gov (United States)

    Hetzinger, S.; Pfeiffer, M.; Dullo, W.-Chr.; Zinke, J.; Garbe-Schönberg, D.

    2016-09-01

    Coral reefs are biologically diverse ecosystems threatened with effective collapse under rapid climate change, in particular by recent increases in ocean temperatures. Coral bleaching has occurred during major El Niño warming events, at times leading to the die-off of entire coral reefs. Here we present records of stable isotopic composition, Sr/Ca ratios and extension rate (1940-2004) in coral aragonite from a northern Venezuelan site, where reefs were strongly impacted by bleaching following the 1997-98 El Niño. We assess the impact of past warming events on coral extension rates and geochemical proxies. A marked decrease in coral (Pseudodiploria strigosa) extension rates coincides with a baseline shift to more negative values in oxygen and carbon isotopic composition after 1997-98, while a neighboring coral (Siderastrea siderea) recovered to pre-bleaching extension rates simultaneously. However, other stressors, besides high temperature, might also have influenced coral physiology and geochemistry. Coastal Venezuelan reefs were exposed to a series of extreme environmental fluctuations since the mid-1990s, i.e. upwelling, extreme rainfall and sediment input from landslides. This work provides important new data on the potential impacts of multiple regional stress events on coral isotopic compositions and raises questions about the long-term influence on coral-based paleoclimate reconstructions.

  1. Modified Distal Urethral Polypropylene Sling (Canal Transobturator Tape Procedure: Efficacy for Persistent Stress Urinary Incontinence After a Conventional Midurethral Sling Procedure

    Directory of Open Access Journals (Sweden)

    Chang Hee Kim

    2013-03-01

    Full Text Available Purpose: Despite reports of persistent stress urinary incontinence (SUI in patients after the midurethral sling (MUS procedure, there is no widely accepted definition or cause of the condition. In many cases, the mesh implanted in the previous MUS procedure has been found to have migrated proximally. The aim of this study was to evaluate the efficacy of the modified distal urethral polypropylene sling, or canal transobturator tape (TOT, procedure for persistent SUI after a conventional MUS procedure on the assumption that persistent SUI after MUS is due to the location of the sling. Methods: From January 2008 to April 2012, 31 female patients who underwent the canal TOT procedure presented with incontinence or lower urinary tract symptoms (LUTS were included in this study. We identified patients who had been operated on by use of the conventional MUS procedure at other medical facilities, whose Valsalva leak pressure point was less than 120 cm-H2O by urodynamic study, and who were also diagnosed with persistent SUI. If vaginal or urethral mesh exposure was concomitant with persistent SUI, the mesh was removed completely or in part. Surgical procedures for canal TOT were identical to the original TOT procedures, except in the number and location of the vaginal incisions. Incontinence Impact Questionnaire-Short Form (IIQ-7 and Urogenital Distress Inventory-Short Form (UDI-6 scores were assessed preoperatively and at 3 months postoperatively. Results: There were no intraoperative or postoperative complications. Twenty-eight patients (90.3% showed improvement in incontinence or other LUTS. Postoperative scores of the IIQ-7 (0.65±0.48 and UDI-6 (3.48±2.28 were significantly improved compared with preoperative scores (1.26±0.58 and 7.52±4.30, respectively; P<0.05. Conclusions: Improper sling location is one of the major causes of persistent SUI after the conventional MUS procedure. Our results demonstrate that canal TOT may be an alternative

  2. Occupational stress and work capacity of nurses of a hospital group Estrés laboral y capacidad para el trabajo de enfermeros de un grupo hospitalario Estresse laboral e capacidade para o trabalho de enfermeiros de um grupo hospitalar

    Directory of Open Access Journals (Sweden)

    Christian Negeliskii

    2011-06-01

    Full Text Available The study aimed to evaluate the relationship between occupational stress and the work capacity index of 368 nurses (82.1% of the population of a Hospital Group. A questionnaire with socio-occupational questions was used as well as two scales: the Job Stress Scale and the Work Capacity Index. The group of nurses was predominantly female (93.2%, worked in care activities (63.9%, had undertaken at least one Postgraduate course (76% and were satisfied with the unit where they worked (70.5%. Occupational stress was present in 23.6% of the nurses, of these 15.2% presented High Strain work and 8.4% Passive Work. Social Support exercised a significant positive influence on all groups - exposed or not to occupational stress. Regarding the Work Capacity, this was Moderate (28-36 points for 51.4% of the nurses and Good (37-43 points for 47.4%. There was no correlation between stress and work capacity.Se trata de un estudio con objetivo de evaluar la relación entre el estrés laboral y el índice de capacidad para el trabajo de 368 enfermeros (82,1% de la población de un Grupo Hospitalario. Se utilizó un cuestionario con cuestiones socio ocupacionales y dos escalas: la Job Stress Scale y el Índice de Capacidad para el Trabajo. El grupo de enfermeros es predominantemente femenino (93,2%, trabaja en actividades asistenciales (63,9%, posee por lo menos un curso de posgraduación (76% y está satisfecho con la unidad donde trabaja (70,5%. El estrés laboral está presente en 23,6% de los enfermeros, de estos 15,2% presentan Alta Exigencia en el trabajo y 8,4% Trabajo Pasivo. El Apoyo Social ejerce influencia positiva significativa sobre todos los grupos expuestos y no expuestos al estrés laboral. En cuanto a la Capacidad para el Trabajo, está es Moderada (28-36 puntos para 51,4% de los enfermeros y Buena (37-43 puntos para 47,4%. No se encontró correlación entre el estrés y la capacidad para el trabajo.Este estudo teve como objetivo avaliar a rela

  3. Zeolites modified with silver for the development of a water disinfection system; Zeolitas modificadas con plata para el desarrollo de un sistema de desinfeccion de agua

    Energy Technology Data Exchange (ETDEWEB)

    Aparicio V, S.

    2013-07-01

    In spite of great strides that have been taken in sanitation technologies, there still exist health problems due to microbiological contamination by water. The waterborne diseases have not been completely eradicated and are a big problem of economic interest and health. Moreover, the microbicidal properties of silver have been used for a long time. The use of silver as a disinfectant has many advantages; for example it inhibits a wide spectrum of microorganisms, it has oligo dynamic properties and owing its mechanisms of cell inactivation, it also does not allow the emergence of new resistant strains. In the present research, the kinetics of water disinfection with silver has been investigated, to develop small system for water disinfection, based in silver modified Mexican clinoptilolite. The chemical species of silver play a significant role in the disinfection processes. For this reason, in this work, were both the Ag{sup +} and nanoparticles of Ag{sup ο} considered. The synthesis of nanoparticles of Ag{sup ο} woes performed by thermal and chemical reduction. It was found that the chemical reduction of Ag{sup +} to Ag{sup ο} was more efficient because it presented more defined nano structures and better distribution than those of thermal reduction. Clinoptilolite of Taxco (Guerrero) was chosen to exchange the native ions from the clinoptilolite by Ag{sup +} from the aqueous medium, or to deposit the nanoparticles of Ag{sup ο} on this surface. These silver modified zeolitic materials were characterized by scanning electron microscopy (Sem), elemental analyses (EDS), X-ray diffraction (XRD) and neutron activation analysis (NAA). The results showed that the crystallographic structure of the clinoptilolite did not change during thermal and chemical reduction treatments of Ag{sup +} to obtain the nanoparticles of Ag{sup ο}. The bactericide activity of the silver modified zeolitic materials (with Ag{sup +} or nanoparticles of Ag{sup ο}) was evaluated on

  4. Modified cyanobacteria

    Science.gov (United States)

    Vermaas, Willem F J.

    2014-06-17

    Disclosed is a modified photoautotrophic bacterium comprising genes of interest that are modified in terms of their expression and/or coding region sequence, wherein modification of the genes of interest increases production of a desired product in the bacterium relative to the amount of the desired product production in a photoautotrophic bacterium that is not modified with respect to the genes of interest.

  5. El impacto de la reducción del estrés en la hipertensión esencial y las enfermedades cardiovasculares. (Impact of stress reduction on essential hypertension and cardiovascular disease.

    Directory of Open Access Journals (Sweden)

    David W. Orme-Johnson

    2008-07-01

    Full Text Available ResumenSe ha considerado que el estrés contribuye a la patogénesis y la progresión de las enfermedades cardiovasculares (ECV. Se ha demostrado que la reducción del estrés mediante la Meditación Trascendental [Transcendental Meditation (TM®] ha bajado los niveles de presión arterial (PA y reducido el riesgo de ECV en adultos y adolescentes. Este artículo repasa los resultados que sugieren el impacto beneficioso de la TM en reducir la PA en adultos hipertensos en reposo y en adolescentes pre-hipertensos en reposo, durante un estrés agudo creado en el laboratorio y durante la actividad diaria normal. Dichos resultados tienen implicaciones importantes para la inclusión de la TM en los esfuerzos que se realizan para prevenir y tratar las ECV y sus consecuencias clínicas.AbstractStress has been thought to contribute to the pathogenesis and progression of cardiovascular diseases (CVD. Stress reduction via Trasncendental Meditation (TM® has been shown to lower blood pressure (BP levels and reduce CVD risk in adults and adolescents. This article reviews findings suggesting a beneficial BP-lowering impact of TM in hypertensive adults at rest and in pre-hypertensive adolescents at rest, during acute laboratory stress and during normal daily activity. These findings have important implications for inclusion of TM efforts to prevent and treat cardiovascular diseases and their clinical consequences.

  6. Hypoxia Stress Modifies Na+/K+-ATPase, H+/K+-ATPase, Na+/NH4+-ATPase, and nkaα1 Isoform Expression in the Brain of Immune-Challenged Air-Breathing Fish

    Science.gov (United States)

    Peter, MC Subhash; Simi, Satheesan

    2017-01-01

    Fishes are equipped to sense stressful stimuli and are able to respond to environmental stressor such as hypoxia with varying pattern of stress response. The functional attributes of brain to hypoxia stress in relation to ion transport and its interaction during immune challenge have not yet delineated in fish. We, therefore, explored the pattern of ion transporter functions and messenger RNA (mRNA) expression of α1-subunit isoforms of Na+/K+-ATPase (NKA) in the brain segments, namely, prosencephalon (PC), mesencephalon (MC), and metencephalon (MeC) in an obligate air-breathing fish exposed either to hypoxia stress (30 minutes forced immersion in water) or challenged with zymosan treatment (25-200 ng g−1 for 24 hours) or both. Zymosan that produced nonspecific immune responses evoked differential regulation of NKA, H+/K+-ATPase (HKA), and Na+/NH4+-ATPase (NNA) in the varied brain segments. On the contrary, hypoxia stress that demanded activation of NKA in PC and MeC showed a reversed NKA activity pattern in MeC of immune-challenged fish. A compromised HKA and NNA regulation during hypoxia stress was found in immune-challenged fish, indicating the role of these brain ion transporters to hypoxia stress and immune challenges. The differential mRNA expression of α1-subunit isoforms of NKA, nkaα1a, nkaα1b, and nkaα1c, in hypoxia-stressed brain showed a shift in its expression pattern during hypoxia stress-immune interaction in PC and MC. Evidence is thus presented for the first time that ion transporters such as HKA and NNA along with NKA act as functional brain markers which respond differentially to both hypoxia stress and immune challenges. Taken together, the data further provide evidence for a differential Na+, K+, H+, and NH4+ ion signaling that exists in brain neuronal clusters during hypoxia stress-immune interaction as a result of modified regulations of NKA, HKA, and NNA transporter functions and nkaα1 isoform regulation. PMID:29238219

  7. Hypoxia Stress Modifies Na+/K+-ATPase, H+/K+-ATPase, [Formula: see text], and nkaα1 Isoform Expression in the Brain of Immune-Challenged Air-Breathing Fish.

    Science.gov (United States)

    Peter, Mc Subhash; Simi, Satheesan

    2017-01-01

    Fishes are equipped to sense stressful stimuli and are able to respond to environmental stressor such as hypoxia with varying pattern of stress response. The functional attributes of brain to hypoxia stress in relation to ion transport and its interaction during immune challenge have not yet delineated in fish. We, therefore, explored the pattern of ion transporter functions and messenger RNA (mRNA) expression of α1-subunit isoforms of Na + /K + -ATPase (NKA) in the brain segments, namely, prosencephalon (PC), mesencephalon (MC), and metencephalon (MeC) in an obligate air-breathing fish exposed either to hypoxia stress (30 minutes forced immersion in water) or challenged with zymosan treatment (25-200 ng g -1 for 24 hours) or both. Zymosan that produced nonspecific immune responses evoked differential regulation of NKA, H + /K + -ATPase (HKA), and [Formula: see text] (NNA) in the varied brain segments. On the contrary, hypoxia stress that demanded activation of NKA in PC and MeC showed a reversed NKA activity pattern in MeC of immune-challenged fish. A compromised HKA and NNA regulation during hypoxia stress was found in immune-challenged fish, indicating the role of these brain ion transporters to hypoxia stress and immune challenges. The differential mRNA expression of α1-subunit isoforms of NKA, nkaα1a , nkaα1b , and nkaα1c , in hypoxia-stressed brain showed a shift in its expression pattern during hypoxia stress-immune interaction in PC and MC. Evidence is thus presented for the first time that ion transporters such as HKA and NNA along with NKA act as functional brain markers which respond differentially to both hypoxia stress and immune challenges. Taken together, the data further provide evidence for a differential Na + , K + , H + , and [Formula: see text] ion signaling that exists in brain neuronal clusters during hypoxia stress-immune interaction as a result of modified regulations of NKA, HKA, and NNA transporter functions and nkaα1 isoform

  8. Biofeedback no tratamento de transtornos relacionados ao estresse e à ansiedade: uma revisão crítica Biofeedback en el tratamiento de trastornos relacionados con el estrés y la ansiedad: una revisión crítica Biofeedback in the treatment of stress and anxiety-related disorders: a critical review

    Directory of Open Access Journals (Sweden)

    Ricardo da Costa Padovani

    2013-04-01

    Full Text Available O treinamento em biofeedback tem sido utilizado para o tratamento de diferentes quadros clínicos e para a prevenção/alívio de sintomas relacionados ao estresse/ansiedade. Este trabalho analisou a literatura de 2008 a 2012 sobre o tema "biofeedback, estresse e ansiedade" publicada nas bases MEDLINE, LILACS e Web of Sciences, utilizando como palavras-chave "biofeedback", "anxiety", "stress", "psychology" e "biofeedback training". Os resultados demonstram que técnicas de biofeedback são eficazes no manejo do estresse/ansiedade nas diferentes populações estudadas. Entretanto, todos os estudos encontrados foram realizados fora do Brasil, o que sugere que técnicas de biofeedback como ferramenta terapêutica não tem sido utilizadas no país, por algum motivo que merece ser melhor investigado.El entrenamiento con biofeedback se ha utilizado para el tratamiento de diferentes manifestaciones clínicas y para la prevención y alivio de síntomas relacionados con el estrés/ansiedad. Este estudio analizó la literatura desde 2008 hasta 2012 sobre el tema "biofeedback, estrés y ansiedad", publicada en MEDLINE, LILACS y Web of Sciences, utilizando como palabras clave "biofeedback", "anxiety", "stress", "psychology" y "biofeedback training". Los resultados demuestran que técnicas de biofeedback son eficaces para el tratamiento del estrés y la ansiedad en diferentes poblaciones. Sin embargo, todos los estudios encontrados se realizaron fuera de Brasil, un indicador de que el biofeedback como herramienta terapéutica no ha sido utilizado en el país por una razón que debe investigarse más a fondo.Biofeedback training has been utilized for the treatment of different pathological conditions, in particular those related to stress/anxiety. This study reviews the scientific literature from 2008 to 2012 about the subject "biofeedback, stress and anxiety", published in MEDLINE, LILACS and Web of Sciences, using as keywords "biofeedback", "anxiety

  9. Changes in polyphenol and sugar concentrations in wild type and genetically modified Nicotiana langsdorffii Weinmann in response to water and heat stress.

    Science.gov (United States)

    Ancillotti, Claudia; Bogani, Patrizia; Biricolti, Stefano; Calistri, Elisa; Checchini, Leonardo; Ciofi, Lorenzo; Gonnelli, Cristina; Del Bubba, Massimo

    2015-12-01

    In this study wild type Nicotiana langsdorffii plants were genetically transformed by the insertion of the rat gene (gr) encoding the glucocorticoid receptor or the rolC gene and exposed to water and heat stress. Water stress was induced for 15 days by adding 20% PEG 6000 in the growth medium, whereas the heat treatment was performed at 50 °C for 2 h, after that a re-growing capability study was carried out. The plant response to stress was investigated by determining electrolyte leakage, dry weight biomass production and water content. These data were evaluated in relation to antiradical activity and concentrations of total polyphenols, selected phenolic compounds and some soluble sugars, as biochemical indicators of metabolic changes due to gene insertion and/or stress treatments. As regards the water stress, the measured physiological parameters evidenced an increasing stress level in the order rolC < gr < WT plants (e.g. about 100% and 50% electrolyte leakage increase in WT and gr samples, respectively) and complied with the biochemical pattern, which consisted in a general decrease of antiradical activity and phenolics, together with an increase in sugars. As regard heat stress, electrolyte leakage data were only in partial agreement with the re-growing capability study. In fact, according to this latter evaluation, gr was the genotype less affected by the heat shock. In this regard, sugars and especially phenolic compounds are informative of the long-term effects due to heat shock treatment. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. Stress analysis in the last stage blade of a geothermal turbine under different excitation conditions; Analisis de esfuerzos en el alabe de la ultima etapa de turbina geotermica bajo diferentes condiciones de excitacion

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Alcazar, Rony Ediberto

    2009-11-15

    The blades of the steam turbines operate below severe conditions of pressure, temperature and steam flow, and at high rotary speeds too. These excitements generate states of stress, which depending on its magnitude and time of application; they can threaten the structural reliability of these mechanical components. In this work a stress analysis is realized in a blade L-0 of a geothermal turbine of low pressure, by means of the finite element method, by the aim to determine the states of static stress caused by the combined action of the centrifugal force and pressure of system flow, and dynamic stresses caused by the harmonic fluctuation in the steam flow. The analysis is realized under two superficial conditions in the blade: without presence of superficial damage and with presence of erosion in the bottom part of the trailing edge. The combined action of these conditions of stress is evaluated by means of an analysis of fatigue. This allows knowing the influence of the stress calculated, on the useful life of the blade. [Spanish] Los alabes de turbinas de vapor operan bajo condiciones severas de presion, temperatura y flujo de vapor, asi como a altas velocidades rotativas. Estas excitaciones generan estados de esfuerzos, que dependiendo de su magnitud y tiempo de aplicacion, pueden amenazar la confiabilidad estructural de estos componentes mecanicos. En este trabajo se realiza un analisis de esfuerzos en un alabe L-0 de una turbina geotermica de baja presion, mediante el metodo de elemento finito, con el objetivo de determinar los estados de esfuerzos estaticos causados por la accion combinada de la carga por fuerza centrifuga y presion de flujo de vapor, y esfuerzos dinamicos causados por la fluctuacion armonica en el flujo de vapor. El analisis se realiza bajo dos condiciones superficiales en el alabe: sin presencia de dano superficial y con presencia de erosion en la parte inferior del borde de salida. La accion combinada de estos estados de esfuerzos se

  11. Evaluation of Fracture Stress for the SiC Layer of TRISO-Coated Fuel Particles by A Modified Crush Testing

    International Nuclear Information System (INIS)

    Byun, Thak Sang; Kim, Jin Weon; Miller, James Henry; Snead, Lance Lewis; Hunn, John D.

    2010-01-01

    Fracture stress data for the chemical vapor deposition (CVD) SiC coatings of tri-isotropic (TRISO) carbon/silicon carbide coated fuel particles were obtained using a newly developed testing and evaluation method, and their relationship with microstructure investigated. A crush testing technique using a blanket foil at load-transferring contact has been developed for hemispherical shell SiC specimens based on finite element (FE) analysis results. Mean fracture stress varied with test material in the range of 330-650 MPa, and was connected to the combined characteristics of inner surface roughness and porosity.

  12. El estrés oxidativo como mecanismo de acción del plomo: Implicancias terapéuticas Oxidative stress as a mechanism of action of lead: Therapeutic implications

    Directory of Open Access Journals (Sweden)

    Samanta Andrea Martínez

    2011-12-01

    Full Text Available El plomo (Pb es un metal no esencial altamente tóxico que afecta a diversos órganos y tejidos. Si bien aún no ha sido descripto un mecanismo único mediante el cual este metal ejerce sus efectos tóxicos, un gran número de estudios han puesto en evidencia el rol fundamental del estrés oxidativo en la intoxicación por Pb. A este respecto, ha sido informado que en la intoxicación por Pb el estrés oxidativo puede ocurrir a diferentes niveles: por generación de ácido ä-aminolevulínico (ä-ALA, por la capacidad per se que posee el Pb para inducir peroxidación lipídica en presencia de ión ferroso (Fe2+, o por depleción de glutatión (GSH y enzimas antioxidantes. Sobre la base de estos antecedentes, el objetivo de esta revisión es presentar evidencias recientes sobre la implicancia del estrés oxidativo en los efectos adversos ocasionados por Pb, destacar la posibilidad de utilización de biomarcadores de estrés oxidativo como un método complementario al diagnóstico temprano de exposición y revelar la importancia de los compuestos antioxidantes como nuevas herramientas en la prevención y tratamiento de la intoxicación por este metal.Lead (Pb is a highly toxic non-essential metal that affects different organs and tissues. Although at the present a unique mechanism by which this metal exerts its toxic effects has not been described, a large number of studies have highlighted the fundamental role of oxidative stress in the pathophysiology of Pb poisoning. In this regard, it has been reported that Pb-induced oxidative stress can occur at different levels: by the generation of ä-aminolevulinic acid (ä-ALA, through its ability to induce lipid peroxidation in the presence of ferrous ion (Fe2+, or via glutathione (GSH or antioxidant enzyme depletion. On the basis of these antecedents, the aim of this review is to present recent evidence regarding the implication of oxidative stress in the adverse effects caused by Pb, to emphasize the

  13. Influencia de la fuerza muscular isométrica de las extremidades superiores en el estrés oxidativo en niños. (Influence of handgrip strength in oxidative stress in children.

    Directory of Open Access Journals (Sweden)

    Manuel Guillén-del Castillo

    2011-01-01

    Full Text Available ResumenEl ejercicio físico puede producir estrés oxidativo en el individuo lo que pueden condicionar el riesgo cardiovascular en niños y adolescentes. Este estudio pretende analizar el estrés oxidativo según la fuerza muscular isométrica de las extremidades superiores en la edad pediátrica. Se estudiaron 70 niños sanos con edades entre 10 y 14 años, y se analizaron en saliva los lipoperóxidos (LPO, el glutatión reducido (GSH, la ratio GSH/LPO y la catalasa, como marcadores de estrés oxidativo. La muestra se dividió en dos grupos según una condición física superior o inferior medida a través de dinamometría manual (TKK 5110; se diferenció la serie en sujetos prepuberales y puberales. Se encontraron niveles significativamente inferiores de GSH y GSH/LPO en el grupo de niños con fuerza superior, y en los puberales con la mismas características; estos resultados podrían indicar la existencia de un mayor estrés oxidativo en esta situación. En conclusión, los mayores niveles de fuerza músculo esquelética, medida a través de dinamometría manual, posiblemente pueden estar asociados a un mayor estrés oxidativo en niños púberes con condición física musculoesquelética superior.AbstractPhysical exercise can produce oxidative stress, this situation could contribute cardiovascular risk in children and adolescents. The following study tries to evaluate the oxidative stress produced according to the handgrip strength in infancy. 70 healthy male subjects, ages 10 to 14 years, were studied. In the saliva samples, lipoperoxides (LPO, reduced glutathione (GSH, glutathione/lipoperoxides ratio and catalase were analyzed as biomarkers of oxidative stress. Children were divided into two groups according to their handgrip strength (high or low measured by handgrip strength (TKK 5110. The groups were also divided into prepubertal and pubertal subjects. We found GSH’s significantly low levels and of GSH/LPO in pubertal group with high

  14. Efecto de la temperatura, el estrés hídrico y luminoso sobre la heterogeneidad del fotosistema II en cuatro variedades de poroto (Phaseolus vulgaris L. Effect of temperature, water and light stress on PSII heterogeneity in four bean varieties (Phaseolus vulgaris L.

    Directory of Open Access Journals (Sweden)

    JAVIERA GONZÁLEZ

    2001-12-01

    diferencias en la magnitud de los cambios observados en las diferentes variedades de poroto, en todos ellos se aprecia la tendencia a modificar la estructura de los centros PSII, de manera de favorecer una menor sobreexcitación de los centros de reacción de dichos complejos, en las situaciones de estrés estudiadasHigher plants have developed multiple mechanisms of photoprotection in order to efficiently use the absorbed energy, as well as protecting the photosynthetic apparatus against oxidative damage. Particularly, under environmental conditions, restrictive for the photochemical use of the absorbed energy, such as high light, water stress and high temperatures. PSII complexes are able to change their location and structure as in PSIIß and state transitions, but not exclusively upon light intensity. In the present study, the effect of different environmental stresses on PSII heterogeneity in four bean cultivar (Phaseolus vulgaris L.: Arroz Tuscola (AT, Orfeo INIA (OI, Bayos Titán (BT and Hallado Dorado (HD, has been assessed. In chamber grown plants, the proportion of the PSIIb centers increases up to a 100 % as the temperature rises. A stronger response was observed, upon water stress. Under field conditions, light stress induced by fixing leaves to horizontal position, further increased the water stress dependent effect on PSIIb centers, from 27 % in free leaves from watered plants up to a 63 % in horizontal leaves from water stressed plants. As for state transitions, an increase was observed in 20 ºC grown plants when exposed to 15 ºC. Also, temperatures from 25 to 35 ºC induced increases in state transitions. Such increases were lowered by water stress, in cultivars AT and OI, maintained in HD and further increased in BT. Even though differences were observed in the extent of the changes on PSIIß and state transitions among varieties, a clear trend to modify the PSII structure in order to decrease its excitation pressure under the stress conditions studied were

  15. Ubiquitin fold modifier 1 (UFM1 and its target UFBP1 protect pancreatic beta cells from ER stress-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Katleen Lemaire

    Full Text Available UFM1 is a member of the ubiquitin like protein family. While the enzymatic cascade of UFM1 conjugation has been elucidated in recent years, the biological function remains largely unknown. In this report we demonstrate that the recently identified C20orf116, which we name UFM1-binding protein 1 containing a PCI domain (UFBP1, and CDK5RAP3 interact with UFM1. Components of the UFM1 conjugation pathway (UFM1, UFBP1, UFL1 and CDK5RAP3 are highly expressed in pancreatic islets of Langerhans and some other secretory tissues. Co-localization of UFM1 with UFBP1 in the endoplasmic reticulum (ER depends on UFBP1. We demonstrate that ER stress, which is common in secretory cells, induces expression of Ufm1, Ufbp1 and Ufl1 in the beta-cell line INS-1E. siRNA-mediated Ufm1 or Ufbp1 knockdown enhances apoptosis upon ER stress. Silencing the E3 enzyme UFL1, results in similar outcomes, suggesting that UFM1-UFBP1 conjugation is required to prevent ER stress-induced apoptosis. Together, our data suggest that UFM1-UFBP1 participate in preventing ER stress-induced apoptosis in protein secretory cells.

  16. Frequent cellular phone use modifies hypothalamic-pituitary-adrenal axis response to a cellular phone call after mental stress in healthy children and adolescents: A pilot study.

    Science.gov (United States)

    Geronikolou, Styliani A; Chamakou, Aikaterini; Mantzou, Aimilia; Chrousos, George; KanakaGantenbein, Christina

    2015-12-01

    The hypothalamic-pituitary-adrenal (HPA) axis is the main "gate-keeper" of the organism's response to every somatic or mental stress. This prospective study aims to investigate the HPA-axis response to a cellular phone call exposure after mental stress in healthy children and adolescents and to assess the possible predictive role of baseline endocrine markers to this response. Two groups of healthy school-age children aged 11-14 (12.5±1.5) years were included in the study, the one comprising those who are occasional users of a cellular phone (Group A) while the second those who do regularly use one (Group B). Blood samples were obtained from all participants at 8.00 am after a 12-hour overnight fasting for thyroid hormone, glucose, insulin, and cortisol levels determination. The participants performed the Trier Social Stress Test for Children (TSST-C) (5 minoral task followed by 5 min arithmetic task). Salivary cortisol samples were obtained at baseline, 10' and 20' min after the TSST-C and 10' and 20' after a 5 minute cellular phone call. Significant changes in the salivary cortisol levels were noted between 10' and 20' mins after the cellular phone call with different responses between the two groups. Baseline thyroid hormone levels seem to predict the cortisol response to mental stress mainly in group A, while HOMA had no impact on salivary cortisol response at any phase of the test, in either group. HPA axis response to cellular phone after mental stress in children and adolescents follow a different pattern in frequent users than in occasional users that seems to be influenced by the baseline thyroid hormone levels. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Heat stress, dehydration, and kidney function in sugarcane cutters in El Salvador--A cross-shift study of workers at risk of Mesoamerican nephropathy.

    Science.gov (United States)

    García-Trabanino, Ramón; Jarquín, Emmanuel; Wesseling, Catharina; Johnson, Richard J; González-Quiroz, Marvin; Weiss, Ilana; Glaser, Jason; José Vindell, Juan; Stockfelt, Leo; Roncal, Carlos; Harra, Tamara; Barregard, Lars

    2015-10-01

    An epidemic of progressive kidney failure afflicts sugarcane workers in Central America. Repeated high-intensity work in hot environments is a possible cause. To assess heat stress, dehydration, biomarkers of renal function and their possible associations. A secondary aim was to evaluate the prevalence of pre-shift renal damage and possible causal factors. Sugarcane cutters (N=189, aged 18-49 years, 168 of them male) from three regions in El Salvador were examined before and after shift. Cross-shift changes in markers of dehydration and renal function were examined and associations with temperature, work time, region, and fluid intake were assessed. Pre-shift glomerular filtration rate was estimated (eGFR) from serum creatinine. The mean work-time was 4 (1.4-11) hours. Mean workday temperature was 34-36 °C before noon, and 39-42 °C at noon. The mean liquid intake during work was 0.8L per hour. There were statistically significant changes across shift. The mean urine specific gravity, urine osmolality and creatinine increased, and urinary pH decreased. Serum creatinine, uric acid and urea nitrogen increased, while chloride and potassium decreased. Pre-shift serum uric acid levels were remarkably high and pre-shift eGFR was reduced (dehydration from strenuous work in a hot and humid environment as an important causal factor. The pathophysiology may include decreased renal blood flow, high demands on tubular reabsorption, and increased levels of uric acid. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. A modified model of pharmacists' job stress: the role of organizational, extra-role, and individual factors on work-related outcomes.

    Science.gov (United States)

    Gaither, Caroline A; Kahaleh, Abir A; Doucette, William R; Mott, David A; Pederson, Craig A; Schommer, Jon C

    2008-09-01

    Understanding the effects of job stress continues to be a concern for health-care providers as workload and personnel needs increase. The overall objective of this study was to test a direct effects model of job stress that examines the characteristics of the organizational environment (interpersonal interactions, environmental aspects, the level of compensation and advancement, role stress, and availability of alternative jobs); extra-role factors (work-home conflict); job stress; individual factors (career commitment); and the work-related psychological outcomes of job satisfaction, organizational commitment, and job turnover intention. A cross-sectional mail survey was sent to a nationwide random sample of 4895 licensed pharmacists in the United States. Previously validated summated Likert-type scales measured each of the study variables. Data analyses included descriptive statistics, and exploratory and confirmatory factor analyses. Structural equation modeling was used to estimate the final model. A response rate of 46% was achieved. Psychometric analyses indicated acceptable reliability and validity. The study model fit the data well (CFI[comparative fit index] = 0.90, RMSEA[root mean square error of approximation] = 0.05). Organizational factors in the form of role overload (standardized beta = 0.45) and conflict (0.31) and ease of finding a job with better interpersonal characteristics (0.26) had the largest effects on job stress. Interpersonal characteristics were also one of the strongest predictors of job satisfaction (-0.61) and organizational commitment (-0.70). Work-home conflict directly affected job turnover intention (0.11) and career commitment (-0.16). Other significant, but sometimes, opposite direct effects were found. Job satisfaction and organizational commitment directly affected job turnover intention. Given the increased demand for pharmacy services, health-care organizations will benefit from increasing positive and reducing negative work

  19. PARTICIPACIÓN EN ACTIVIDADES FÍSICAS DURANTE EL TIEMPO LIBRE Y SU RELACIÓN CON EL ESTRÉS TRAUMÁTICO SECUNDARIO EN BOMBEROS [Participation of physical activities during free time and the relation of the secundary traumatic stress in firefigther

    Directory of Open Access Journals (Sweden)

    Jimmy Fernando Rojas-Quirós

    2015-01-01

    Full Text Available El propósito fue analizar cómo la actividad física (AF puede tener relación con procesos psicológicos como el Estrés Traumático Secundario (ETS en bomberos, para ello se examinó cuál era el nivel de participación en AF durante el tiempo libre y la prevalencia de ETS en 56 bomberos seleccionados por conveniencia. Se aplicó el Cuestionario de Estrés Traumático Secundario y el Cuestionario Mundial sobre Actividad Física (GPAQ. Se encontró que un 80.3% de los bomberos presentan un nivel de AF moderada y vigorosa en el tiempo libre, invirtiendo en promedio 2662.86 MET-min/semana. El nivel de AF correlaciona positiva y significativamente con la dimensión de Trauma Secundario o Sintomatología del ETS (r =.324, sig. .015, la cual presenta mayor prevalencia (32.1% en la muestra, seguida de Sacudidas de Creencias con un 17.9%. En conclusión, los bomberos que presentan mayores niveles de AF en el tiempo libre tienden a mostrar una mayor afectación de ETS, específicamente en la dimensión de Trauma secundario o Sintomatología.AbstractThe purpose was to analyze the relationship between the participation of physical activity (PA and the psychological processes of Secondary Traumatic Stress (STS on firefighters. Levels of participation in PA during free time and prevalence of STS were measured in a convenience sample of 56 firefighters using the Secondary Traumatic Stress Questionnaire and the Global Physical Activity Questionnaire. Findings show that 80.3% of the firefighters report moderate and vigorous free time-PA levels, investing an average of 2662.86 MET-min/week. Free time-PA levels show positive and significant correlations with the Secondary Trauma/Symptoms subscale of STS (r=.324, sig. .015, which is the factor with higher prevalence (32.1%, followed by Shattered Assumptions with 17.9%. In conclusion, firefighters with higher levels of free time-PA tend to report higher scores of ETS, specifically regarding to Secondary Trauma/Symptoms.

  20. A Modified Eyring Equation for Modeling Yield and Flow Stresses of Metals at Strain Rates Ranging from 10−5 to 5 × 104 s−1

    Directory of Open Access Journals (Sweden)

    Ramzi Othman

    2015-01-01

    Full Text Available In several industrial applications, metallic structures are facing impact loads. Therefore, there is an important need for developing constitutive equations which take into account the strain rate sensitivity of their mechanical properties. The Johnson-Cook equation was widely used to model the strain rate sensitivity of metals. However, it implies that the yield and flow stresses are linearly increasing in terms of the logarithm of strain rate. This is only true up to a threshold strain rate. In this work, a three-constant constitutive equation, assuming an apparent activation volume which decreases as the strain rate increases, is applied here for some metals. It is shown that this equation fits well the experimental yield and flow stresses for a very wide range of strain rates, including quasi-static, high, and very high strain rates (from 10−5 to 5 × 104 s−1. This is the first time that a constitutive equation is showed to be able to fit the yield stress over a so large strain rate range while using only three material constants.

  1. The FEM Analysis of Stress Distribution in front of the Crack Tip and Fracture Process in the Elements of Modified and Unmodified Cast Steel G17CrMo5-5

    Directory of Open Access Journals (Sweden)

    Pała Robert

    2016-09-01

    Full Text Available The article presents influence of modification of the low-alloy cast steel G17CrMo5-5 by rare earth metals on stress distribution in front of the crack at the initial moment of the crack extension. Experimental studies include determination of strength and fracture toughness characteristics for unmodified (UM and modified (M cast steel. In the numerical computations, experimentally tested specimens SEN(B were modelled. The true stress–strain curves for the UM and M cast steel are used in the calculation. The stress distributions in front of the crack were calculated at the initial moment of the crack extension. On the basis of data on the particle size inclusions in the UM and M cast steel, and the calculated stress distributions was performed an assessment of the possibility of the occurrence of cleavage fracture. The analysis results indicate that at room temperature for the UM cast steel, there is a possibility of cleavage fracture, while for the M cast steel occurrence of cleavage fracture is negligible.

  2. El estrés docente: elaboración de la escala ed-6 para su evaluación. [ Educational stress: elaboration of ed-6 scale for its assesment

    Directory of Open Access Journals (Sweden)

    Santiago Morán-Suárez

    2005-02-01

    Full Text Available The educational stress is an investigation topic that monopolizes or great number of studies. In the work that here is presented, the psychometrics properties of the scale ED-6 are analyzed. This scale was elaborated ad hoc to measure the stress or educational discomfort of face to their use in a wider frame of investigations on this phenomenon. As he/she will be able to be proven, the results show a reliability and acceptable validity, being conformed for 77 ítems and 6 dimensions: Anxiety, Depression, Pressures, Beliefs, Amotivation and Bad confrontation. It is expected that its use in future investigations is of great profit. El estrés docente es un tema de investigación que acapara un gran número de estudios. En el trabajo que aquí se presenta, se analizan las propiedades psicométricas de la escala ED-6,elaborada ad hoc para medir el estrés o malestar docente de cara a su utilización en un marco más amplio de investigaciones sobre este fenómeno. Como se podrá comprobar, los resultados muestran una fiabilidad y validez aceptable, quedando conformada por 77 ítems y 6 dimensiones: Ansiedad, Depresión, Presiones, Creencias, Desmotivación y Mal afrontamiento. Se espera que su uso en futuras investigaciones resulte de gran provecho

  3. The influence of modified water chemistries on metal oxide films, activity build-up and stress corrosion cracking of structural materials in nuclear power plants

    International Nuclear Information System (INIS)

    Maekelae, K.; Laitinen, T.; Bojinov, M.

    1999-03-01

    The primary coolant oxidises the surfaces of construction materials in nuclear power plants. The properties of the oxide films influence significantly the extent of incorporation of actuated corrosion products into the primary circuit surfaces, which may cause additional occupational doses for the maintenance personnel. The physical and chemical properties of the oxide films play also an important role in different forms of corrosion observed in power plants. This report gives a short overview of the factors influencing activity build-up and corrosion phenomena in nuclear power plants. Furthermore, the most recent modifications in the water chemistry to decrease these risks are discussed. A special focus is put on zinc water chemistry, and a preliminary discussion on the mechanism via which zinc influences activity build-up is presented. Even though the exact mechanisms by which zinc acts are not yet known, it is assumed that Zn may block the diffusion paths within the oxide film. This reduces ion transport through the oxide films leading to a reduced rate of oxide growth. Simultaneously the number of available adsorption sites for 60 Co is also reduced. The current models for stress corrosion cracking assume that the anodic and the respective cathodic reactions contributing to crack growth occur partly on or in the oxide films. The rates of these reactions may control the crack propagation rate and therefore, the properties of the oxide films play a crucial role in determining the susceptibility of the material to stress corrosion cracking. Finally, attention is paid also on the novel techniques which can be used to mitigate the susceptibility of construction materials to stress corrosion cracking. (orig.)

  4. The Influence Of Modified Water Chemistries On Metal Oxide Films, Activity Build-Up And Stress Corrosion Cracking Of Structural Materials In Nuclear Power Plants

    International Nuclear Information System (INIS)

    Maekelae, K.; Laitinen, T.; Bojinov, M.

    1998-07-01

    The primary coolant oxidises the surfaces of construction materials in nuclear power plants. The properties of the oxide films influence significantly the extent of incorporation of activated corrosion products into the primary circuit surfaces, which may cause additional occupational doses for the maintenance personnel. The physical and chemical properties of the oxide films play also an important role in different forms of corrosion observed in power plants. This report gives a short overview of the factors influencing activity build-up and corrosion phenomena in nuclear power plants. Furthermore, the most recent modifications in the water chemistry to decrease these risks are discussed. A special focus is put on zinc water chemistry, and a preliminary discussion on the mechanism via which zinc influences activity build-up is presented. Even though the exact mechanisms by which zinc acts are not yet known, it is assumed that Zn may block the diffusion paths within the oxide film. This reduces ion transport through the oxide films leading to a reduced rate of oxide growth. Simultaneously the number of available adsorption sites for 60 Co is also reduced. The current models for stress corrosion cracking assume that the anodic and the respective cathodic reactions contributing to crack growth occur partly on or in the oxide films. The rates of these reactions may control the crack propagation rate and therefore, the properties of the oxide films play a crucial role in determining the susceptibility of the material to stress corrosion cracking. Finally, attention is paid also on the novel techniques which can be used to mitigate the susceptibility of construction materials to stress corrosion cracking. (author)

  5. The influence of modified water chemistries on metal oxide films, activity build-up and stress corrosion cracking of structural materials in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Maekelae, K.; Laitinen, T.; Bojinov, M. [VTT Manufacturing Technology, Espoo (Finland)

    1999-03-01

    The primary coolant oxidises the surfaces of construction materials in nuclear power plants. The properties of the oxide films influence significantly the extent of incorporation of actuated corrosion products into the primary circuit surfaces, which may cause additional occupational doses for the maintenance personnel. The physical and chemical properties of the oxide films play also an important role in different forms of corrosion observed in power plants. This report gives a short overview of the factors influencing activity build-up and corrosion phenomena in nuclear power plants. Furthermore, the most recent modifications in the water chemistry to decrease these risks are discussed. A special focus is put on zinc water chemistry, and a preliminary discussion on the mechanism via which zinc influences activity build-up is presented. Even though the exact mechanisms by which zinc acts are not yet known, it is assumed that Zn may block the diffusion paths within the oxide film. This reduces ion transport through the oxide films leading to a reduced rate of oxide growth. Simultaneously the number of available adsorption sites for {sup 60}Co is also reduced. The current models for stress corrosion cracking assume that the anodic and the respective cathodic reactions contributing to crack growth occur partly on or in the oxide films. The rates of these reactions may control the crack propagation rate and therefore, the properties of the oxide films play a crucial role in determining the susceptibility of the material to stress corrosion cracking. Finally, attention is paid also on the novel techniques which can be used to mitigate the susceptibility of construction materials to stress corrosion cracking. (orig.) 127 refs.

  6. Comprendre et intervenir sur le stress au travail : une étude de cas Understand and intervene on work stress: a case study Comprender e intervenir en el estrés laboral : un estudio de caso

    Directory of Open Access Journals (Sweden)

    Emmanuel Poirel

    2011-05-01

    Full Text Available Cet article tente de mettre à l’épreuve le modèle émotivo-transactionnel sur la base de données recueillies grâce à un dispositif de confrontation vidéo (autoconfrontation. Il met en évidence une distorsion classique de ce modèle qui sert à légitimer des interventions psycho-organisationnelles centrées sur l’individu. L’analyse précise et détaillée d’un incident prenant place dans le cadre des missions de sécurité d’agent de train montre que le stress pathologique est de l’ordre d’une expérience de l’impuissance. Sur la base du cas étudié, il est ainsi possible de relier stress et anxiété en insistant sur la dimension de l’évaluation cognitive reposant sur la présence ou l’absence de ressources.This article presents a case study using stimulated recall by selfconfrontation based on the emotional-transactional model of stress. The detailed and specific analysis of an incident in a railway company shows that stress is more an experience of powerlessness. Therefore, it highlights a traditional distortion of the transactional model used to legitimate psycho-organizational interventions focused on the individual. Thus, on the basis of this case study, it is possible to link stress and pathological consequences to anxiety by showing the consequences relating to the perception of having few resources to cope with the situation.Éste articulo intenta probar el modelo emocional-transaccional sobre la base de datos tomados gracias a un dispositivo de confrontación con video (auto-confrontación. Se pone en evidencia la distorsión clásica de este modelo que sirve a legitimar las intervenciones psico-organizacionales centradas en el individuo. El análisis preciso y detallado de un incidente que se produjo en el marco de misiones de seguridad de una compañía de trenes mostró que el estrés patológico es del orden de una experiencia de impotencia. Sobre la base del caso estudiado, es así posible relacionar

  7. Nuevas expresiones para el cálculo a torsión de costuras soldadas de filete de configuración compleja. // New expressions for torsion shear stress calculation in welding fillets.

    Directory of Open Access Journals (Sweden)

    H. Hernández Herrera

    2004-09-01

    Full Text Available En el presente trabajo se aplica la Teoría de la Torsión de Perfiles de Paredes Delgadas para el cálculo de las tensiones enlas uniones soldadas con costuras de filete en perfiles de configuración geométrica compleja sometidas a torsión. Seobtienen nuevas expresiones para el cálculo de las tensiones cuyos resultados se aproximan mejor que las expresionesclásicas con relación a los resultados obtenidos por el Método de los Elementos Finitos.Palabras claves: Torsión, uniones soldadas, soldadura de filete._______________________________________________________________________________Abstract.In this paper, the Thin Walled profiles Torsion Theory is applied to calculation of torsional shear stresses of complex geometryprofiles welded joints fillets. New calculation expressions are obtained that allowed to obtain a better aproach than the classicexpressions in relation to the values obtained by the Finite Elements Method.Key words: Torsion, welded joints, welding fillets.

  8. Stress in nurses working in intensive care units El estrés de los enfermeros que actúan en una unidad de terapia intensiva Estresse de enfermeiros com atuação em unidade de terapia intensiva

    Directory of Open Access Journals (Sweden)

    Ana Maria Cavalheiro

    2008-02-01

    Full Text Available The present study aimed to identify the presence of stress in nurses working in intensive care units, the stressing agents and symptoms associated to the nurses' perceptions of stress, and to assess the correlation between the occurrence of stress, sources of stress, and symptoms shown by the nurses. Seventy-five nurses took part in the study. The data were collected from questionnaires, analyzed with the Pearson correlation coefficients, and adjusted by general linear models. The study showed the presence of stress related to work dissatisfaction, activities regarded as critical situations in intensive care units, symptoms related to cardiovascular, digestive and musculoskeletal disorders. The conclusion is that stress is present in nurses' activities in intensive care units, related to characteristics of the health area itself, causing dissatisfaction and stress-related symptoms.El presente estudio tuvo como objetivos: identificar la presencia de estrés en enfermeros que trabajan en unidades de terapia intensiva; identificar a los agentes estresantes y a los síntomas asociados al estrés, según la percepción del enfermero; y, evaluar la correlación entre la presencia del estrés, las fuentes del estrés y los síntomas presentados por los enfermeros. Setenta y cinco enfermeros participaron del estudio. Los datos fueron recolectados por medio de cuestionarios. El análisis fue realizado utilizando los coeficientes de correlación de Pearson y ajustando con modelos lineales generalizados. El estudio mostró la presencia de estrés correlacionado a: la insatisfacción en el trabajo; a las actividades consideradas como situaciones críticas en unidad de terapia intensiva; a los síntomas relacionados con alteraciones cardiovasculares; al aparato digestivo y a los músculos del esqueleto. La conclusión del estudio es que el estrés está presente en la actividad del enfermero en las unidades de terapia intensiva y está correlacionado a

  9. Modified SEAGULL

    Science.gov (United States)

    Salas, M. D.; Kuehn, M. S.

    1994-01-01

    Original version of program incorporated into program SRGULL (LEW-15093) for use on National Aero-Space Plane project, its duty being to model forebody, inlet, and nozzle portions of vehicle. However, real-gas chemistry effects in hypersonic flow fields limited accuracy of that version, because it assumed perfect-gas properties. As a result, SEAGULL modified according to real-gas equilibrium-chemistry methodology. This program analyzes two-dimensional, hypersonic flows of real gases. Modified version of SEAGULL maintains as much of original program as possible, and retains ability to execute original perfect-gas version.

  10. Calidad de vida y estrés laboral: la incidencia del Burnout en el deporte de alto rendimiento madrileño. Quality of life and job stress: Burnout among high performance sport professionals from Madrid.

    Directory of Open Access Journals (Sweden)

    Martínez del Castillo, Jesús

    2007-01-01

    Full Text Available ResumenEn la literatura sobre la psicología de la salud en las organizaciones es generalmente aceptado que el Burnout (Síndrome de quemarse por el trabajo aparece como consecuencia de un estrés laboral crónico excesivo que provoca una disminución de la habilidad en el desempeño de la actividad profesional y la aparición de diferentes problemas de salud en quien lo padece. El Burnout (Síndrome de quemarse por el trabajo ha sido conceptualizado como un síndrome psicológico tridimensional de agotamiento emocional, despersonalización y baja realización personal en el trabajo. El propósito de este estudio es evaluar la presencia del Burnout en el colectivo de los profesionales del Alto Rendimiento Deportivo. Para ello se utilizó una muestra de 102 profesionales en activo empleados en 20 organizaciones representativas del fenómeno del Alto Rendimiento Deportivo de la ciudad de Madrid, España. Para medir la incidencia del Burnout (Síndrome de quemarse por el trabajo se utilizó el Inventario de Burnout de Maslach. Los resultados obtenidos en este colectivo fueron de un 37,25% con altos niveles de Burnout (Síndrome de quemarse por el trabajo, 50% con nivel intermedio y 12,75% con bajo nivel. Estos profesionales presentan mayores niveles de baja realización personal en el trabajo (26,47% y menores niveles de despersonalización (11,76% y agotamiento emocional (10,78%. También se encontraron diferencias en los niveles cuando fueron comparados con otros profesionales del deporte.AbstractIt is widely accepted in organizational and health psychology literatures that burnout is a consequence of chronic job stress wh+ºich causes an array of negative work related performance and health outcomes. Burnout was conceptualized as a 3-dimensional psychological syndrome consisting of emotional exhaustion, depersonalization and decreased personal accomplishment. The purpose of this study was to assess the presence of Burnout syndrome in High

  11. EL TIEMPO

    OpenAIRE

    Jaramillo Ochoa, Jaramillo

    2009-01-01

    El tiempo es el aliado misterioso que nos envuelve y nos transporta, nos permite ser viajeros de nuestro propio tren sin reglas. Cómo saber qué tiempo tomar... Cómo saber qué tiempo ceder... Cómo saber cuando el tiempo es correcto... Es silencioso, es voraz, es traicionero, el peor de los enemigos: el tiempo no perdona. Cómo saber si el tiempo se detiene.

  12. Do psychosocial stress and social disadvantage modify the association between air pollution and blood pressure?: the multi-ethnic study of atherosclerosis.

    Science.gov (United States)

    Hicken, Margaret T; Adar, Sara D; Diez Roux, Ana V; O'Neill, Marie S; Magzamen, Sheryl; Auchincloss, Amy H; Kaufman, Joel D

    2013-11-15

    Researchers have theorized that social and psychosocial factors increase vulnerability to the deleterious health effects of environmental hazards. We used baseline examination data (2000-2002) from the Multi-Ethnic Study of Atherosclerosis. Participants were 45-84 years of age and free of clinical cardiovascular disease at enrollment (n = 6814). The modifying role of social and psychosocial factors on the association between exposure to air pollution comprising particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5) and blood pressure measures were examined using linear regression models. There was no evidence of synergistic effects of higher PM2.5 and adverse social/psychosocial factors on blood pressure. In contrast, there was weak evidence of stronger associations of PM2.5 with blood pressure in higher socioeconomic status groups. For example, those in the 10th percentile of the income distribution (i.e., low income) showed no association between PM2.5 and diastolic blood pressure (b = -0.41 mmHg; 95% confidence interval: -1.40, 0.61), whereas those in the 90th percentile of the income distribution (i.e., high income) showed a 1.52-mmHg increase in diastolic blood pressure for each 10-µg/m(3) increase in PM2.5 (95% confidence interval: 0.22, 2.83). Our results are not consistent with the hypothesis that there are stronger associations between PM2.5 exposures and blood pressure in persons of lower socioeconomic status or those with greater psychosocial adversity.

  13. Evaluación del efecto de modificadores y refinadores en el comportamiento mecánico y magnitud del rechupe de aleaciones Al-Si-Mg. // Modifier and refiners effect evaluation in the magnitude and mechanical shrinkage behavior of Al-Si-Mg alloys.

    Directory of Open Access Journals (Sweden)

    V. Lavaert

    2002-05-01

    Full Text Available Se estudia la influencia del Na, Sr y Ti y sus combinaciones (Na-Ti y Sr-Na en las propiedades mecánicas y el rechupe(superior y lateral de la aleación hipoeutéctica AlSi7Mg Aunque todos estos elementos y combinaciones tienden aneutralizar la formación del rechupe substancialmente, el Sr se presenta como el más eficaz para disminuir el rechupesuperior mientras la combinación Na-Ti llevó a la menor formación de rechupe lateral.Se observó una acción modificadora excelente para 0.02% de Sr y 0.02% de Na, pero a diferencia del Sr, el efectomodificador del Na comienza a desvanecerse después de 30 min afectando el alargamiento notablemente. El estroncio, sinembargo, mostró un efecto de la modificación muy duradero (aproximadamente 3 h. Otro hallazgo interesante es laexistencia de un cierto periodo de incubación de aproximadamente 90 minutos después de agregar Sr. Contrariamente a loesperado el uso de titanio no mejoró las propiedades mecánicas a pesar de un eficaz refinamiento de grano.Palabras claves: Rechupe superior, acción modificadora, propiedades mecánicas, metalurgia no ferrosa._________________________________________________________________________AbstractThe influence of Na, Sr and Ti and their combinations (Na-Ti and Sr-Na on the mechanical properties and the shrinkage(top macro shrinkage and lateral macro shrinkage of hypoeutectic aluminium-silicon alloys (AlSi7xMg has been studied.Although all these elements and combinations tend to counteract substantially the shrinkage formation, Sr appeared to bethe most effective to decrease top macro shrinkage whereas the combination Na-Ti led to the least formation of lateralmacro shrinkage. An excellent modifying action was observed for 0.02% Sr and 0.02% Na, but unlike Sr the modifyingeffect provided by Na started fading after 30 min of holding which affected the elongation markedly. However, strontiumshowed a very lasting modification effect (about 3 h. Another interesting

  14. Activation of phagocytic cells by Staphylococcus epidermidis biofilms: effects of extracellular matrix proteins and the bacterial stress protein GroEL on netosis and MRP-14 release.

    Science.gov (United States)

    Dapunt, Ulrike; Gaida, Matthias M; Meyle, Eva; Prior, Birgit; Hänsch, Gertrud M

    2016-07-01

    The recognition and phagocytosis of free-swimming (planktonic) bacteria by polymorphonuclear neutrophils have been investigated in depth. However, less is known about the neutrophil response towards bacterial biofilms. Our previous work demonstrated that neutrophils recognize activating entities within the extracellular polymeric substance (EPS) of biofilms (the bacterial heat shock protein GroEL) and that this process does not require opsonization. Aim of this study was to evaluate the release of DNA by neutrophils in response to biofilms, as well as the release of the inflammatory cytokine MRP-14. Neutrophils were stimulated with Staphylococcus epidermidis biofilms, planktonic bacteria, extracted EPS and GroEL. Release of DNA and of MRP-14 was evaluated. Furthermore, tissue samples from patients suffering from biofilm infections were collected and evaluated by histology. MRP-14 concentration in blood samples was measured. We were able to show that biofilms, the EPS and GroEL induce DNA release. MRP-14 was only released after stimulation with EPS, not GroEL. Histology of tissue samples revealed MRP-14 positive cells in association with neutrophil infiltration and MRP-14 concentration was elevated in blood samples of patients suffering from biofilm infections. Our data demonstrate that neutrophil-activating entities are present in the EPS and that GroEL induces DNA release by neutrophils. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Estresse da equipe de enfermagem do corpo de bombeiros no Atendimento Pré-Hospitalar Móvel El estrés del equipo de enfermería del cuerpo de bomberos en atención pre-hospitalaria móvil Stress at the nursing staff from the fire department in a mobile pre-hospital care

    Directory of Open Access Journals (Sweden)

    Richiére dos Santos Pereira Salvador

    2013-06-01

    profesionales.The research has as subject, the study of the stress at work on a nursing staff from the Fire Department in the pre - hospital care, and aims to identify what are the stressors in the work of professionals who are part of the nursing staff of APH Mobile from the Fire Department; analyze the impact of stress on the health of these professionals. The study characterized itself as qualitative descriptive - exploratory, involving 10 professionals. Data collection was conducted through interviews recorded electronically, using a semi-structured instrument. After transcription of the interviews, the similar aspects and differences found were grouped into analyze categories. It was confirmed that these professionals are subjected to constant stress, having modified their lifestyle habits, with health impact. It is suggested that the identified problems are studied in order to develop strategies in order to generate better working conditions for these professionals.

  16. Supervisory system for real time monitoring of transient thermal stresses in turbines rotors; Sistema supervisorio para el monitoreo en tiempo real de esfuerzos termicos transitorios en rotores de turbinas

    Energy Technology Data Exchange (ETDEWEB)

    Urquiza Beltran, Gustavo; Rios Miranda, Edmundo; Venegas Guzman, Ricardo; Alvarez Garcia, Gabriela [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1991-12-31

    This article presents a supervisory system that, as its main functions, assists the operator on base of the thermal stresses, monitoring in real time the high pressure (HP) and intermediate pressure rotors (IP) of a steam turbine during the start, shut down and/or sudden load changes. The system is based on a thermal model uni-dimensional integrated to the SIMPER (Information System for the Predictive Maintenance of Rotating Equipment), tested in a 300 MW unit of Comision Federal de Electricidad (CFE). [Espanol] En este articulo se presenta un sistema supervisorio que, como funciones principales, asiste al operador con base en el monitoreo de esfuerzos termicos en tiempo real en los rotores de presion alta (PA) y presion intermedia (PI) de una turbina de vapor durante un arranque, paro y/o variaciones bruscas de carga. El sistema esta basado en un modelo termico unidimensional integrado al SIMPER (sistema informatico para el mantenimiento predictivo de equipo rotatorio), experimentado en una unidad de 300 MW de la Comision Federal de Electricidad (CFE).

  17. Supervisory system for real time monitoring of transient thermal stresses in turbines rotors; Sistema supervisorio para el monitoreo en tiempo real de esfuerzos termicos transitorios en rotores de turbinas

    Energy Technology Data Exchange (ETDEWEB)

    Urquiza Beltran, Gustavo; Rios Miranda, Edmundo; Venegas Guzman, Ricardo; Alvarez Garcia, Gabriela [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1992-12-31

    This article presents a supervisory system that, as its main functions, assists the operator on base of the thermal stresses, monitoring in real time the high pressure (HP) and intermediate pressure rotors (IP) of a steam turbine during the start, shut down and/or sudden load changes. The system is based on a thermal model uni-dimensional integrated to the SIMPER (Information System for the Predictive Maintenance of Rotating Equipment), tested in a 300 MW unit of Comision Federal de Electricidad (CFE). [Espanol] En este articulo se presenta un sistema supervisorio que, como funciones principales, asiste al operador con base en el monitoreo de esfuerzos termicos en tiempo real en los rotores de presion alta (PA) y presion intermedia (PI) de una turbina de vapor durante un arranque, paro y/o variaciones bruscas de carga. El sistema esta basado en un modelo termico unidimensional integrado al SIMPER (sistema informatico para el mantenimiento predictivo de equipo rotatorio), experimentado en una unidad de 300 MW de la Comision Federal de Electricidad (CFE).

  18. Severely Burdened Individuals Do Not Need to Be Excluded From Internet-Based and Mobile-Based Stress Management: Effect Modifiers of Treatment Outcomes From Three Randomized Controlled Trials.

    Science.gov (United States)

    Weisel, Kiona Krueger; Lehr, Dirk; Heber, Elena; Zarski, Anna-Carlotta; Berking, Matthias; Riper, Heleen; Ebert, David Daniel

    2018-06-19

    Although internet-based and mobile-based stress management interventions (iSMIs) may be a promising strategy to reach employees suffering from high chronic stress, it remains unknown whether participants with high symptom severity of depression or anxiety also benefit from iSMIs or should be excluded. This study aimed to evaluate the efficacy of iSMIs in subgroups with high symptom severity and to test whether baseline symptom severity moderates treatment outcome. Data from three randomized controlled trials (N=791) were pooled to identify effect modifiers and to evaluate efficacy in subgroups with different levels of initial symptom severity. The outcomes perceived stress (Perceived Stress Scale, PSS), depression severity (Center for Epidemiological Depression Scale, CES-D), and anxiety (Hospital Anxiety and Depression Scale, HADS) symptom severity were assessed at baseline, 7-week postassessment, and 6-month follow-up. Potential moderators were tested in predicting differences in the change of outcome in multiple moderation analyses. Simple slope analyses evaluated efficacy of the iSMI comparing the intervention group with the waitlist control group in subgroups with low, moderate, and severe initial symptomology based on means and SDs of the study population. In addition, subgroups with clinical values of depression (CES-D≥16) and anxiety (HADS≥8) at baseline were explored, and response rates (RRs; 50% symptom reduction) and symptom-free (SF) status (CES-Dhttps://www.drks.de/DRKS00005112 (Archived by WebCite at http://www.webcitation.org/6zmIZwvdA); 2) German Clinical Trials Register DRKS00005384; https://www.drks.de/ DRKS00005384 (Archived by WebCite at http://www.webcitation.org/6zmIerdtr); and 3) German Clinical Trials Register DRKS00004749; https://www.drks.de/DRKS00004749 (Archived by WebCite at http://www.webcitation.org/6zmIjDQPx). ©Kiona Krueger Weisel, Dirk Lehr, Elena Heber, Anna-Carlotta Zarski, Matthias Berking, Heleen Riper, David Daniel Ebert

  19. Entrenamiento Aeróbico: Efecto Sobre el Estado Oxidativo Hepático. [Aerobic Training: Effect on Liver Oxidative Stress].

    Directory of Open Access Journals (Sweden)

    Nyurky Josefina Matheus

    2016-07-01

    Full Text Available El ob­jetivo de este estudio fue evaluar en un modelo animal el efecto del entrenamiento aeróbico y del ejercicio eventual sobre el estado oxidativo hepático. Se utilizaron 30 ratones machos NMRI, divididos en 3 grupos de 10: Control (sin ejercicio, Entrenamiento Aeróbico (EA y Ejercicio Eventual (EE. La actividad física se realizó en una rueda de ejercicio que giraba a 50 rpm/ (30 minutos. día por 6 semanas para el grupo con EA y a 50 rpm/ 30 minutos, una vez para el EE. Se determinó en sangre la concentración de albúmina, y en hígado se cuantificó la concentración de Dienos Conjugados, Malondialdehido, Glutatión Reducido (GSH, y se realizó el estudio histopatológico. Los resultados muestran que los animales que realizaron EE presentaron un aumento marcado de la lipoperoxidación (LPO hepática comparado con el grupo control y con los de EA. Con respecto a la respuesta antioxidante, la concentración de GSH aumentó en los animales de EA y disminuyó en los de EE, la albúmina fue menor en los animales que se ejercitaron. El cociente GSH/LPO fue mayor en los animales de EA, lo que indica una disminución de la LPO en relación con la respuesta antioxidante dada por el GSH. Los resultados de este estudio muestran que a pesar de que ocurre un aumento de la lipoperoxidación hepática durante el ejercicio, esta oxidación no altera la estructura histológica del órgano y dependiendo del tipo de ejercicio, el organismo se adapta produciendo aumento de la defensa antioxidante, base esta del entrenamiento. Abstract The aim of this study was to evaluate in an animal model the effect of aerobic training on hepatic oxidative status. Control (without exercise Aerobic Training (EA and Exercise Eventually (EE: 30 NMRI male mice were divided into 3 groups of 10 were used. Physical activity was conducted in an exercise wheel rotating at 50 rpm / 30 minutes / day / six weeks for the group with AD and 50 rpm / 30 minutes / once for EE. Albumin

  20. Interfacial Modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Ina; French, Roger H.

    2018-03-19

    Our project objective in the first and only Budget Period was to demonstrate the potential of nm-scale organofunctional silane coatings as a method of extending the lifetime of PV materials and devices. Specifically, the target was to double the lifetime performance of a laminated Cu(In,Ga)Se2 (CIGS) cell under real-world and accelerated aging exposure conditions. Key findings are that modification of aluminum-doped zinc oxide (AZO) films (materials used as transparent conductive oxide (TCO) top contacts) resulted in decreased degradation of optical and electrical properties under damp heat (DH) exposure compared to un-modified AZO. The most significant finding is that modification of the AZO top contact of full CIGS devices resulted in significantly improved properties under DH exposure compared to un-modified devices, by a factor of 4 after 1000 h. Results of this one-year project have demonstrated that surface functionalization is a viable pathway for extending the lifetime of state-of-the-art CIGS devices.

  1. Change of residual stresses during plastic deformation under uniaxial tension test; Variacion de las tensiones residuales con la deformacion plastica en el ensayo de traccion

    Energy Technology Data Exchange (ETDEWEB)

    Benito, J. A.; Jorba, J.; Roca, A.

    2001-07-01

    Hang of longitudinal and transverse residual stresses was studied by X Ray diffraction method as the applied plastic deformation, measured as A% was increased in a standard tension test. The starting material, hot rolling Armco iron, has values close to 0 MPa in longitudinal direction. But it reaches 600 MPa with only A=1,5%, this value remains constant until necking is produced. In transverse direction the stating values are 300 MPa, changes are small and residual stresses remain compressive until the end of tension test. In addition, studies of the changes of residual stresses with time and with misalignment between incident X Ray and drawing direction are presented. (Author) 5 refs.

  2. El agua y el arte

    Directory of Open Access Journals (Sweden)

    Chueca Goitia, Fernando

    1999-10-01

    Full Text Available Not available.En el artículo «El agua y el arte» se analiza la importancia que tiene el agua en el mundo del arte, a través de los jardines y sus muchas variedades. El autor se refiere luego a los diversos aspectos que tienen el jardín francés, el jardín inglés, y el jardín español, de acuerdo con su geografía, pluviometría y cultura propias. El jardín español de abolengo musulmán es el jardín de los países secos que atesoran el agua como bien precioso, porque no lo regala la naturaleza y es necesario transportarlo y encerrarlo en el cofre de una arquitectura sugerente. Por eso el jardín español es un jardín recoleto y misterioso, enclaustrado y secreto, sin lejanías ni perspectivas. Se extiende luego el autor en los jardines de la Alhambra granadina, sin olvidar otros, principalmente andaluces. Jardines de los claustros monacales, de El Escorial y de los Sitios reales, también interesan, en suma, al articulista.

  3. Risoterapia en atletas de la Facultad de Cultura Física de Pinar del Río. Una alternativa contra el stress

    Directory of Open Access Journals (Sweden)

    Fernando Emilio Valladares Fuente

    2006-06-01

    Full Text Available Es notable lo bien y relajados que nos hace sentir reírnos durante una película cómica, un programa de televisión o un evento humorístico. Del origen de la risa se conoce mucho menos de lo que se sabe sobre sus ventajas. La primera de ellas es el bienestar inmediato durante y después de una carcajada.

  4. L’autoévaluation du stress au travail : un indicateur de santé trompeur Self-assessment of stress in the workplace: a misleading health indicator La auto-evaluación del estrés en el trabajo : un indicador engañoso de salud

    Directory of Open Access Journals (Sweden)

    Michel Vézina

    2010-05-01

    Full Text Available L’objectif de l’étude est de documenter les liens entre certaines contraintes psychosociales du travail et certains problèmes de santé mentale, et ce, à partir des données pour le Québec du cycle 1.2 de l’Enquête sur la santé dans les collectivités canadiennes. Les résultats indiquent une augmentation significative du faible soutien social entre 2002 et 2005 qui passe de 45 % à 49 %, alors que le nombre de personnes se disant stressées au travail s’est amélioré de façon significative entre 2000-01 et 2005, passant de 42 % à 38 %. De plus, la faible autonomie de compétence est associée à moins de stress au travail, alors que cette dimension est reconnue pathogène pour la santé mentale. L’autoévaluation du stress au travail apparaît donc comme un indicateur de santé trompeur, puisqu’il n’évalue pas les dimensions reconnues pathogènes pour la santé mentale.The purpose of this study is to document the relationships between some psychosocial constraints in the workplace and some mental health problems based on data for Québec from Cycle 1.2 of the Canadian Community Health Survey. From 2002 to 2005, results indicate a significant increase in weak social support from 45% to 49%, while for the same period, the number of persons indicating being stressed at work decreased significantly, dropping from 42% to 38%. However, while less autonomy in the workplace is associated with less stress at work, this dimension is also recognized as pathogenic for mental health. Therefore, self-assessment of stress in the workplace appears to be a misleading health indicator, since it fails to assess dimensions recognized as pathogenic for mental health.El objetivo de este estudio es documentar los lazos entre ciertas exigencias psicosociales del trabajo y ciertos problemas de salud mental, a partir de datos para Québec del ciclo 1.2 de la Encuesta sobre la salud en las colectividades canadienses. Los resultados indican un

  5. Self-assessment of stress in the workplace: a misleading health indicator L’autoévaluation du stress au travail : un indicateur de santé trompeur La auto-evaluación del estrés en el trabajo : un indicador engañoso de salud

    Directory of Open Access Journals (Sweden)

    Michel Vézina

    2010-05-01

    Full Text Available The purpose of this study is to document the relationships between some psychosocial constraints in the workplace and some mental health problems based on data for Québec from Cycle 1.2 of the Canadian Community Health Survey. From 2002 to 2005, results indicate a significant increase in weak social support from 45% to 49%, while for the same period, the number of persons indicating being stressed at work decreased significantly, dropping from 42% to 38%. However, while less autonomy in the workplace is associated with less stress at work, this dimension is also recognized as pathogenic for mental health. Therefore, self-assessment of stress in the workplace appears to be a misleading health indicator, since it fails to assess dimensions recognized as pathogenic for mental health.L’objectif de l’étude est de documenter les liens entre certaines contraintes psychosociales du travail et certains problèmes de santé mentale, et ce, à partir des données pour le Québec du cycle 1.2 de l’Enquête sur la santé dans les collectivités canadiennes. Les résultats indiquent une augmentation significative du faible soutien social entre 2002 et 2005 qui passe de 45 % à 49 %, alors que le nombre de personnes se disant stressées au travail s’est amélioré de façon significative entre 2000-01 et 2005, passant de 42 % à 38 %. De plus, la faible autonomie de compétence est associée à moins de stress au travail, alors que cette dimension est reconnue pathogène pour la santé mentale. L’autoévaluation du stress au travail apparaît donc comme un indicateur de santé trompeur, puisqu’il n’évalue pas les dimensions reconnues pathogènes pour la santé mentale.El objetivo de este estudio es documentar los lazos entre ciertas exigencias psicosociales del trabajo y ciertos problemas de salud mental, a partir de datos para Québec del ciclo 1.2 de la Encuesta sobre la salud en las colectividades canadienses. Los resultados indican un

  6. El factoring

    Directory of Open Access Journals (Sweden)

    Alberto Rosenthal

    1988-04-01

    Full Text Available RESUMEN El artículo  presenta, una conceptualización general de lo que es el factoring, el origen del mismo, su evolución y hace una clasificación de los distintos tipos de factoring.

  7. DnaK and GroEL chaperones are recruited to the Bacillus subtilis membrane after short-term ethanol stress

    Czech Academy of Sciences Publication Activity Database

    Seydlová, G.; Halada, Petr; Fišer, R.; Toman, O.; Ulrych, Aleš; Svobodová, J.

    2012-01-01

    Roč. 112, č. 4 (2012), s. 765-774 ISSN 1364-5072 R&D Projects: GA MŠk LC07017 Institutional research plan: CEZ:AV0Z50200510 Keywords : Bacillus subtilis * ethanol stress * membrane Subject RIV: EE - Microbiology, Virology Impact factor: 2.196, year: 2012

  8. Effects of overexpression of IL-1 receptor-associated kinase on NFkappaB activation, IL-2 production and stress-activated protein kinases in the murine T cell line EL4.

    Science.gov (United States)

    Knop, J; Wesche, H; Lang, D; Martin, M U

    1998-10-01

    The association and activation of the IL-1 receptor-associated protein kinase (IRAK) to the IL-1 receptor complex is one of the earliest events detectable in IL-1 signal transduction. We generated permanent clones of the murine T cell line EL4 6.1 overexpressing human (h)IRAK to evaluate the role of this kinase in IL-1 signaling. Overexpression of hIRAK enhanced IL-1-stimulated activation of the transcription factor NFkappaB, whereas a truncated form (N-IRAK) specifically inhibited IL-1-dependent NFkappaB activity. In clones stably overexpressing hIRAK a weak constitutive activation of NFkappaB correlated with a low basal IL-2 production which was enhanced in an IL-1-dependent manner. Compared to the parental cell line the dose-response curve of IL-1-induced IL-2 production was shifted in both potency and efficacy. These results demonstrate that IRAK directly triggers NFkappaB-mediated gene expression in EL4 cells. Qualitatively different effects were observed for the IL-1-induced activation of stress-activated protein (SAP) kinases: permanent overexpression of IRAK did not affect the dose dependence but prolonged the kinetics of IL-1-induced activation of SAP kinases, suggesting that this signaling branch may be regulated by distinct mechanisms.

  9. El perfume

    OpenAIRE

    Allegretti, Silvina A.

    2006-01-01

    El perfume (1985) relata la vida de Jean-Baptiste Grenouille, un ser proscrito nacido en el mercado de Les Halles. Como su madre intenta asesinarlo, el recién nacido es puesto bajo el amparo de varias nodrizas, que se deshacen de él – sistemáticamente- horrorizadas ante el niño que no despide “olor humano”. La ironía de la pluma creadora le asigna a Grenouille una contraparte especialísima: la criatura inodora tiene la capacidad de captar todos los aromas de París.

  10. El Caucho

    Directory of Open Access Journals (Sweden)

    Brandes E. W.

    1942-12-01

    Full Text Available En tiempo de emergencia nacional el insignificante arbusto denominado Guayule se ha convertido en una importante fuente de producción cauchera. Después de años de permanecer a la sombra de su más renombrado competidor, el árbol de Hevea, el Guayule salió a la luz el 5 de marzo de 1942 cuando el Presidente Roosevelt firmó un decreto autorizando un programa oficial para la explotación del arbusto como medio de ampliar las fuentes de provisión de caucho de las Naciones Unidas.

  11. El Alcanfor

    Directory of Open Access Journals (Sweden)

    García Paredes Antonio

    1941-08-01

    Full Text Available El alcanfor es un cuerpo natural, pertenece al reino vegetal; es blanco, brillante, semitrasparente, aromático, duro, sólido, liviano, inflamable, volátil, pulverizable al ponerle unas gotas de alcohol, soluble en el alcohol y en los aceites, insoluble en el agua, medicinal e industrial. Entre los muchos vegetales que suministra alcanfor el más importante y antiguamente conocido es el Laurel Alcanfor, árbol centenario y frondoso de la familia de las Laurineas, propio del Japón y de la China.

  12. El alcanfor

    OpenAIRE

    García Paredes, Antonio

    2012-01-01

    El alcanfor es un cuerpo natural, pertenece al reino vegetal; es blanco, brillante, semitrasparente, aromático, duro, sólido, liviano, inflamable, volátil, pulverizable al ponerle unas gotas de alcohol, soluble en el alcohol y en los aceites, insoluble en el agua, medicinal e industrial. Entre los muchos vegetales que suministra alcanfor el más importante y antiguamente conocido es el Laurel Alcanfor, árbol centenario y frondoso de la familia de las Laurineas, propio del Japón y de la Chin...

  13. Estrés laboral en profesores de enseñanza secundaria: examinando el papel de las conductas y/o actitudes problemáticas de los alumnos y la dificultad percibida en el manejo de conflictos. Occupational stress in secondary school teachers: examining the role of students’ disruptive behaviour and/or attitudes and the perceived difficulty in conflict management

    Directory of Open Access Journals (Sweden)

    María J. Santiago

    2008-03-01

    Full Text Available

    En este trabajo se examina, en función de distintas variables sociodemográficas y ocupacionales (sexo, edad, experiencia profesional, ciclo de docencia, no sólo el papel de las conductas y/o actitudes problemáticas de los alumnos, sino también las dificultades percibidas por los profesores en el manejo de conflictos. Los resultados obtenidos, a partir de una muestra de 1.386 docentes de ESO, permiten concluir que ambos tipos de estresores diferencian válidamente en función de las variables sociodemográficas y ocupacionales. Concretamente, el estrés asociado a los problemas de comportamiento de los alumnos y a las dificultades del docente en el manejo de conflictos, incide en mayor medida en las profesoras, en los docentes de segundo ciclo y en aquellas etapas intermedias de la profesión. En definitiva, si estos hallazgos se ratifican en futuras investigaciones, se trataría de diseñar programas preventivos y/o de intervención que sean sensibles a estos factores de riesgo.

    Palabras clave: Estrés, profesores, conductas problema alumnos, manejo conflictos.

    This study examines not only the role of students’ disruptive behaviour and/or attitudes but also the difficulties perceived by teachers in managing conflicts as a function of the different sociodemographic and occupational variables (gender, age, professional experience, teaching cycle. The results obtained from a sample consisting in 1386 ESO teachers allow us to conclude that both types of stressors validly discriminate as a function of sociodemographic and occupational variables. Specifically, the stress associated to students’ disruptive behaviour and to the difficulties faced by teachers in managing conflict has a greater incidence on female teachers, on second cycle teachers and on intermediate stages in the profession. If these findings are corroborated by further research, it would be important to design prevention and/or intervention programmes that are

  14. RESISTENCIA MECÁNICA EVALUADA EN EL ENSAYO MARSHALL DE MEZCLAS DENSAS EN CALIENTE ELABORADAS CON ASFALTOS MODIFICADOS CON DESECHOS DE POLICLORURO DE VINILO (PVC, POLIETILENO DE ALTA DENSIDAD (PEAD Y POLIESTIRENO (PS MECHANICAL RESISTANCE OF HOT THICK MIXTURES MADE WITH ASPHALT MODIFIED WITH POLYVINYL CHLORIDE, POLYCLORURE (PVC WASTES, HIGH DENSITY POLYETHYLENE (PEAD, AND POLYSTYRENE (PS EVALUATED IN MARSHALL ASSAY

    Directory of Open Access Journals (Sweden)

    Hugo Alexánder Rondón Quintana

    2007-07-01

    Full Text Available El presente trabajo buscó evaluar en laboratorio el cambio en la resistencia mecánica que experimentan mezclas asfálticas densas en caliente cuando se adicionan, por vía húmeda, al cemento asfáltico aditivos poliméricos producto de desechos industriales del tipo plastómero (policloruro de vinilo, polietileno de alta densidad y poliestireno. Para tal fin se empleó el ensayo Marshall. De los resultados obtenidos se concluye que la resistencia mecánica de mezclas asfálticas modificadas con desechos del tipo plastómero es mayor en comparación con las convencionales (mezclas que emplean asfaltos sin ningún aditivo.The main objective of this research Project was to evaluate in a laboratory the change in mechanical strength that dense hot asphalt mixtures go through when waste polymeric additives of plastomeric type (polyvinyl chloride, high density polyethylene and polystyrene are added to asphalt cement, by 'wet way'. This change was evaluated using Marshall Test. The general conclusion of the experimental results was that modified hot asphalt mixtures present better mechanical behavior than conventional mixtures (mixtures which use asphalt without additives.

  15. El trasplante autólogo de células mesoteliales como acelerador y modificador de la cicatrización cutánea en ratas Autologous mesothelial cells transplantation as accelerator and skin healing modifier in rats

    Directory of Open Access Journals (Sweden)

    R. Esparza Iturbide

    2013-03-01

    Full Text Available El propósito del presente estudio fue comprobar si el autotrasplante de células mesoteliales peritoneales en heridas de espesor total en ratas acelera y modifica el proceso de cicatrización cutánea normal, basándonos en la teoría de que las células mesoteliales provenientes de tejidos como el peritoneo, pleura o pericardio, son responsables de uno de los procesos de cicatrización más rápidos y sintetizan varios factores estimulantes y quimiotácticos de la cicatrización (causantes de las adherencias intraabdominales, además de que poseen la capacidad de diferenciarse en otras series celulares (plasticidad. Diseñamos un estudio experimental, analítico, longitudinal, prospectivo y comparativo, en el Laboratorio de Cirugía Experimental del Centro Médico ABC Observatorio, México D.F. (México. Se emplearon 15 ratas cepa Wistar, divididas en 2 grupos: Grupo I (n=5 en el que previa anestesia general, se extirparon 3 mm. de diámetro de piel de la región dorsal mediante técnica microquirúrgica y cierre por segunda intención; y Grupo II (n=10 en el que se realizó minilaparotomía con escisión de peritoneo parietal, cierre primario de la misma, escisión de piel de espesor total en región dorsal de 3 mm. de diámetro y colocación del autoinjerto peritoneal en la herida dorsal. En el análisis histológico se revisaron 6 variables: colágeno, fibroblastos, número de vasos, macrófagos, células inflamatorias y grado de retracción, para puntualizar integralmente el tipo y características de la cicatrización en ambos grupos. El análisis estadístico de datos se elaboró con Statistical Package of Social Sciences 17.0. Se realizó estadística descriptiva por medio de medidas de frecuencia, de tendencia central y de dispersión. Los resultados mostraron que los individuos del Grupo I presentaron mayor inflamación, fibrosis y retracción, datos compatibles con una fase proliferaría de cicatrización. En el Grupo II se encontr

  16. O estresse entre enfermeiros que atuam em Unidade de Terapia Intensiva El estrés entre enfermeros que actúan en las Unidades de Terapia Intensiva Stress among nurses who work at the intensive care unit

    Directory of Open Access Journals (Sweden)

    Vivian Aline Preto

    2009-12-01

    demuestra que el estrés, inclusive siendo discutido desde hace mucho tiempo, todavía acomete a esos profesionales, y las instituciones todavía no ofrecen atención especial a los enfermeros en el sentido de promover su salud integral.Stress has been observed among various professionals, including intensive care unit (ICU nurses, due to their close contact with patients in distress and at the risk of death. This situation becomes worse due to the need for direct and intensive care. This study was performed to characterize nurses working at ICU and verify the presence of stress among them. A total of 21 ICU nurses from five hospitals located in the state of São Paulo answered a series of questions about the ICU and completed the Nurse Stress Inventory. Study results showed that 57.1% of nurses consider the ICU a stressful place, and 23.8% achieved a high score, indicating the presence of stress. Stress continues to affect these professionals, and institutions do not offer any special care for nurses in the sense of promoting comprehensive health care.

  17. J.O. no. 10 of the 13 january 2004, page 991, text no. 14. Decrees, orders. General texts. Decree no. 2004-47 of the 12 january 2004 modifying the decree no. 96-978 of the 31 october 1996 relative to the creation of the nuclear installation no. 162 named EL4-D, installation of storage for the Monts d'Arree power plants materials; J.O. no. 10 du 13 janvier 2004, page 991, texte no. 14. Decrets, arretes, circulaires. Textes generaux. Decret no. 2004-47 du 12 janvier 2004 modifiant le decret no. 96-978 du 31 octobre 1996 relatif a la creation de l'installation nucleaire de base no. 162 denommee EL4-D, installation d'entreposage de materiels de la centrale nucleaire des monts d'Arree

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    The reactor EL4, implemented in december 1966, has definitely shutdown on the 31 july 1985. This reactor was an industrial prototype, built and exploited by Cea and EDF. In the framework of the partial dismantling of the installation, the decree 96-978 of the 31 october 1996 agreed the Cea to modify the installation to become a storage installation. (A.L.B.)

  18. Modified Koyanagi Technique in Management of Proximal ...

    African Journals Online (AJOL)

    xp

    Modified Koyanagi Technique in Management of Proximal Hypospadias. Adham Elsaied, Basem Saied, and Mohammed El- ... All operations were performed by the authors,using fine instruments and under 3.5X loupe ... the other needed an operation to close the fistula six months later. The case with meatal recession had ...

  19. J.O. no. 10 of the 13 january 2004, page 991, text no. 14. Decrees, orders. General texts. Decree no. 2004-47 of the 12 january 2004 modifying the decree no. 96-978 of the 31 october 1996 relative to the creation of the nuclear installation no. 162 named EL4-D, installation of storage for the Monts d'Arree power plants materials

    International Nuclear Information System (INIS)

    2004-06-01

    The reactor EL4, implemented in december 1966, has definitely shutdown on the 31 july 1985. This reactor was an industrial prototype, built and exploited by Cea and EDF. In the framework of the partial dismantling of the installation, the decree 96-978 of the 31 october 1996 agreed the Cea to modify the installation to become a storage installation. (A.L.B.)

  20. Structural, dielectric and piezoelectric study of Ca-, Zr-modified ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 40; Issue 5. Structural, dielectric and piezoelectric study of Ca-, Zr-modified BaTiO 3 lead-free ceramics. H MSOUNI A TACHAFINE M EL AATMANI D FASQUELLE J C CARRU M EL HAMMIOUI M RGUITI A ZEGZOUTI A OUTZOURHIT M DAOUD. Volume 40 Issue 5 ...

  1. El carriel

    Directory of Open Access Journals (Sweden)

    Jaime Mejía Duque

    1967-05-01

    Full Text Available En el caniel, objeto de cuero de res con el que nuestros campesinos de la zona montañosa occidental complementan su atuendo de trabajo y al que suelen exhibir también en ocasiones solemnes, se da una síntesis viva del utensilio y de los símbolos primarios de origen materno-infantil.

  2. El Ajo

    Directory of Open Access Journals (Sweden)

    Carda Paredes Antonio

    1942-08-01

    Full Text Available El Ajo es del género ALLIUM, AJO, de la familia de las LILIACEAS. El ajo es una planta exótica, herbácea, anual, que fue traída de España junto con la cebolla, su congénere, en la época de la Colonia, y se aclimató muy bien en los climas fríos. El ajo es también planta bulbífera, y el bulbo llamado vulgarmente CABEZA está compuesto de varios bulbillos llamados DIENTES, cubiertos cada uno de una túnica muy delgada, seca y blanquecina. El olor del ajo es más fuerte y más difusible que el de la cebolla y basta que se le despoje de su cubierta o película que lo cubre para que este olor se deje sentir vivamente a alguna distancia. Examinado químicamente el ajo, contiene las siguientes sustancias: mucílago, azúcar, azufre, sales y un aceite volátil amarillo muy acre y de sabor muy fuerte. A este aceite se atribuyen las propiedades excitantes del bulbo. El aceite volátil del ajo se extrae por destilación de los bulbos frescos. Este acéite contiene azufre y es más pesado que el agua. El ajo no es alimenticio pero es un condimento indispensable en todas las preparaciones del arte culinario.

  3. El consumo de alcohol y el estrés entre estudiantes del segundo año de enfermería Consumo de álcool e estresse em estudantes do segundo ano de enfermagem Alcohol consumption and stress in second year nursing students

    Directory of Open Access Journals (Sweden)

    Elena Tam Phun

    2010-06-01

    Full Text Available El objetivo de este estudio fue identificar el consumo de alcohol y el estrés académico en estudiantes de enfermería. Se trata de una investigación descriptiva, transversal, que se realizó en el año de 2005. En este estudio los cuestionarios Inventario de Estrés Académico y el AUDIT fueron aplicados en 82 estudiantes de una Universidad privada en Lima, Perú. Los resultados mostraron que los estudiantes tenían edad promedio 20,4 años, siendo 92.7% solteras, 69.5% no trabajan, 91.5% no tenían hijos y 86.6% vivían con sus padres. La sobrecarga académica representó el estresor de mayor prevalencia, y en relación al consumo de alcohol, 48% consumieron 1-2 vasos en un día; 56.1% una vez al mes y 51.2% más de tres vasos en un día cualquiera; 11.0% dejaron de cumplir con sus obligaciones. Un tercio relató fumar, beber o comer demasiado. Se concluyó que todas las situaciones generan diversos niveles de estrés, relacionados al factor actividad/tiempo; siendo la preocupación, la mayor respuesta frente al estrés.O objetivo deste estudo foi identificar o consumo de álcool e o estresse acadêmico em estudantes de Enfermagem. Como método, usou-se a investigação descritiva, transversal, realizada no ano 2005. Neste estudo, os questionários Inventário de Estresse Acadêmico e AUDIT foram aplicados em 82 estudantes de uma universidade privada em Lima, Peru. Os resultados mostram que os estudantes apresentaram idade média de 20,4 anos, sendo que 92,7% eram solteiros, 69,5% não trabalhavam, 91,5% não tinham filhos e 86,6% viviam com seus pais. A sobrecarga acadêmica representou o estressor de maior prevalência e, em relação ao consumo de álcool, 48% consumiam 1-2 copos por dia, 56,1% uma vez ao mês e 51,2% mais de três copos em um dia qualquer, e 11% deixaram de cumprir com suas obrigações. Um terço relatou fumar, beber ou comer demasiadamente. Conclui-se que todas as situações geraram diversos níveis de estresse

  4. El alma en el carriel

    Directory of Open Access Journals (Sweden)

    Daniel Echeverri

    1981-01-01

    Full Text Available Sobre la tierra el hombre es la varilla de un breve reloj solar que marca la hora alta o temprana de su civilizacion. Allí está en mitad de la plaza aldeana el día de mercado -círculo suyo- nuestro campesino hincado siempre al suelo como una banderilla.

  5. El poder en el cine

    OpenAIRE

    Brisset Mart??n, Demetrio E.

    2008-01-01

    Desde la antropolog??a visual, se aborda la faceta del Poder relativa a sus diversas manifestaciones. Entre ellas, elegimos el cine, especialmente su g??nero de drama judicial, y analizamos comparativamente El proceso f??lmico de Welles y la novela de Kafka.

  6. El Camino Hacia el Valor Razonable

    Directory of Open Access Journals (Sweden)

    Ana Zorio Grima

    2002-06-01

    Full Text Available Ante la exigencia de que las empresas europeas cotizadas elaboren sus estados financieros consolidados de acuerdo con la normativa del IASE a partir de 2005, la Unión Europea ha modificado recientemente la IV y VII Directivas para introducir el valor razonable como criterio de medición de los instrumentos financieros. De este modo, se posibilita el cumplimiento de la lAS 39, sin quebrantar las disposiciones comunitarias. No obstante, ello supone un importante cambio en el modelo contable europeo, en el que hasta ahora regía el principio del precio de adquisición, sólidamente sustentado por el principio de prudencia. En este trabajo enmarcamos teóricamente este nuevo criterio de valoración y su introducción en nuestro ámbito más próximo, así como su posible extensión a otras áreas contables de acuerdo con las últimas tendencias internacionales. Asimismo, presentamos una revisión de la investigación empírica realizada en diferentes países, fundamentalmente del ámbito anglosajón, sobre los efectos de este método de valoración en las distintas partidas del balance que son susceptibles de su aplicación. En un futuro, muy probablemente se abrirán también líneas similares de investigación en nuestro país.Since listed companies will be required to prepare their consolidated annual accounts in accordance with IASB standards, from 2005 at the la test, the European Commission has recently modified the IV and VII Accounting Directives, in order to introduce fair value accounting for financial instruments. This way, companies can comply with IAS 39 and observe at the same time the European dispositions. Nonetheless, this is an important change in the European Accounting model, which has been up to now based on the historic cost, according to the principle of prudence. In this paper, we analyse the theoretical framework for this valuation criterion and provide some insight for its introduction in our environment. Moreover, we look

  7. Evaluación de la eficiencia energética de vehículos pesados en el ciclo // Evaluation of the heavy duty trucks energy efficiency in the modified drive cycle.

    Directory of Open Access Journals (Sweden)

    Ramón Pérez-Gálvez

    2010-01-01

    Full Text Available ResumenEn este trabajo, se presenta la reformulación de un ciclo teórico que consta de los elementosbásicos de un ciclo de viaje real con condiciones prefijadas de movimiento y operación. En lamodificación se tomaron en cuenta los siguientes elementos: frecuencia de rotación mínima enmovimiento estable; eficiencia de la transmisión variable con la velocidad, la carga y la marchaconectada; un nuevo criterio de frecuencia de rotación del motor para el cambio de marchas; elfrenado con el motor embragado y; nuevas expresiones de cuantificación del consumo decombustible. Obteniéndose nuevos modelos matemáticos para la determinación de los indicadoresdel consumo de combustible de vehículos pesados de transmisión mecánica. Se presenta además,un indicador “Coeficiente de Efectividad del Trabajo del Automóvil” (CETA que describe laeficiencia energética durante el periodo de impulso, expresada a través del grado deaprovechamiento de la energía del automóvil para llevar hasta determinada velocidad la masa de lacarga útil.Palabras claves: ciclo de viaje, consumo de combustible, evaluación vehicular, modelos matemáticos._________________________________________________________________AbstractIn this paper, the new formulation of a theoretical drive cycle is presented. It is integrated by stagesof a real drive cycle with the prefix settings of movement and operation. In the cycle modificationthe following approaches are taken account: minimal rotation frequency in stable movement; thetransmission efficiency is variable with the speed, the weight, and the gear ratio; a new rotationfrequency for gear shifting; a motor braking stage and; a group of new equations for the fuelconsumption. New mathematical models were obtained for the fuel consumption indicators of theheavy duty trucks with manual transmission. Furthermore, the indicator Automobile WorkEffectiveness Coefficient is presented. It describes the energy efficiency in the

  8. El mielograma

    Directory of Open Access Journals (Sweden)

    Guillermo López Escobar

    1944-01-01

    Sitio. - La parte media de la primera vértebra del cuerpo del cuerpo es escogida como el mejor lugar para la punción medular, pues en este sitio desde el nacimiento están reunidos, en la línea media, los centros medulares, y persisten activos durante casi toda la vida, a más de que ángulo de Louis, siempre notorio, representa un buen punto de mira ya que forma el límite superior de la primera vértebra esternal.

  9. 1mamoune el himri; abdelouahad el himri ;; agustín pastor

    African Journals Online (AJOL)

    Michael Horsfall

    Full-text Available Online at www.ajol.info and www.bioline.org.br/ja. INFLUENCE OF THE MEASUREMENT MEDIUM AND MATRIX MODIFIERS ON THE DETERMINATION OF SILICON. IN WATERS BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROMETRY. *1MAMOUNE EL HIMRI; ABDELOUAHAD EL HIMRI;; ...

  10. El Quijote

    Directory of Open Access Journals (Sweden)

    Jorge Ortega Torres

    1963-05-01

    Full Text Available Ha querido la Academia Colombiana conmemorar por medio de la presente festividad el tercer centenario de la muerte de Miguel de Cervantes Saavedra, y entre los números de su programa ha puesto el discurso que voy a pronunciar. El contrastará por su aridez con la otra pieza de esta velada, en la cual han corrido los primores de la forma a porfía con la belleza y sublimidad de las ideas. De esta suerte me quedará siempre la satisfacción de haber contribuído para el follaje de la corona ofrendada por la Academia a una de las primeras glorias de la literatura española y universal.

  11. El Piretro

    Directory of Open Access Journals (Sweden)

    Ocampo J. Alcides

    1941-08-01

    Full Text Available Perteneciente a la numerosa Familia de las Compositáceas, el Piretro es una planta que se cultiva por sus flores, las que se aprovechan en la preparación de insecticidas, por los principios activos que contiene (piretrinas. El lugar originario del Piretro es Persia, donde se le ha conocido desde varios siglos atrás. Fue introducido en Europa a principios del siglo XIX, adonde se exportaban tanto las flores secas, como el polvo. Su demanda fue cada día mayor, por su uso en el exterminio de los vermes. Algunos años después, entre 1850 y 1860, se introdujeron en Dalmacia otras especies, las que probaron ser más efectivas que las importadas de Persia. La propagación del Piretro en Europa fue rápida, habiendo tenido su grado floreciente a fines del siglo pasado.

  12. El proceso constituyente venezolano

    Directory of Open Access Journals (Sweden)

    Ricardo COMBELLAS

    2009-11-01

    Full Text Available RESUMEN: La Asamblea Nacional Constituyente permitirá redefinir el marco institucional de la república venezolana. Este proceso constituyente iniciado en 1989 aborda una etapa definitiva debido al apoyo mayoritario de los venezolanos y a que ha sido asumido como bandera por el hoy presidente Hugo Chávez.El paradigma constitucional ha tenido tropiezos originados por el populismo, el clientelismo, la corrupción, la falta de un trabajo legislativo oportuno, la falta de garantías a los derechos fundamentales, el deterioro del poder judicial y la falta de una participación política abierta.Para llevar a cabo una asamblea nacional constituyente es fundamental la participación amplia que lleve a un consenso constructivo. Es decir, se tratará de iniciar el 25 de abril una constituyente originaria que implica que su capacidad decisoria no esté sujeta a ningún poder establecido, ya que su origen es la expresión política de la soberanía popular que va a modificar el ordenamiento jurídico existente.ABSTRACT: The National Assembly Constituency will permit the redefinition of the institutional framework of the Venezuelan Republic. This fundamental process started in 1989 outlines a definitive stage due to the major support of the Venezuela people, and has been assumed as the platform of present president Hugo Chávez.The constitutional paradigm has flaws that originate from the following: populism, clientelism, corruption, the lack of timely legislative work, the lack of guarantees to basic rights, the deterioration of judicial power, and the lack of open political participation.For the National Assembly Constituency to work, extensive participation is fundamental to bring forth constructive consensus. As its origins now is the political expression of popular sovereignty that modifies the existing judicial order, it wil try to iniciate on the 25th of April a new constituency that implies that its capacity for decision making is not subject to

  13. El perro y el frisbee

    Directory of Open Access Journals (Sweden)

    Vasileios Madouros

    2012-12-01

    Full Text Available Este escrito analiza por qué el tipo de regulación financiera compleja desarrollado en las últimas décadas puede ser una respuesta subóptima a la creciente complejidad del sistema financiero. Los ejemplos de otras disciplinas muestran que la toma de decisiones en un entorno complejo se puede beneficiar con el uso de reglas prácticas simples o “heurísticas”. Una serie de experimentos empíricos para evaluar el desempeño relativo de las reglas simples y complejas en el entorno financiero muestra que los indicadores simples, como la relación de apalancamiento y las medidas de capital basadas en el mercado superan a las medidas más complejas ponderadas por el riesgo y a los modelos de múltiples indicadores en su capacidad para predecir quiebras bancarias. Un mensaje congruente de estos experimentos es que la complejidad de los modelos o los portafolios puede generar problemas de robustez. Presenta cinco lecciones de política a partir de estos resultados, relacionadas con el diseño de la regulación financiera y las posibles medidas encaminadas a reducir en forma más directa la complejidad del sistema financiero.

  14. El basurero

    Directory of Open Access Journals (Sweden)

    Bradbury Ray

    1999-12-01

    Full Text Available Asi era su trabajo: se levantaba a las cinco de las fria y oscura mañanay se lavaba la cara con agua caliente si el aparato de calefaccion funcionaba y con agua fria si el aparato no funcionaba. Se afeitaba cuidadosamente, hablandole a su mujer en la cocina, que preparaba jamon y huevos o panqueques o lo que hubiera aquella mañana.

  15. El viaje y el arquitecto

    OpenAIRE

    Baladrón, Alfredo

    2014-01-01

    A lo largo de la historia, la formación del arquitecto ha venido acompañada por el viaje. El “grand tour” completaba, inicialmente, los conocimientos de historia y composición, pero servía, a su vez, como una fuente de experiencias que acompañarían al arquitecto a lo largo de su vida y obra. El hecho mismo de viajar supone una deslocalización, una tabula rasa en la que los sentidos se despiertan y agudizan, haciendo del sujeto una caja de resonancia sensible que permite una profunda asimilaci...

  16. El periodista y el verbo

    Directory of Open Access Journals (Sweden)

    Hernán Rodríguez Castelo

    2015-01-01

    Full Text Available Presente, antepretérito de subjuntivo, antepospretérito de indicativo, imperativo, ¿potencial?, son algunos de los tiempos y modos verbales del castellano, con los cuales se han dicho en nuestra lengua todas las acciones, "desde el Quijote hasta las más briosas, aventuras de ciencia ficción", ¿Conoce, el periodista, esta rica gama verbal? ¿Cómo manejar los dieciséis tiempos verbales adecuadamente? En el siguiente texto, algunas pistas al respecto.

  17. El principio es el crimen

    OpenAIRE

    Claudio, Lara María; Sánchez, María Eduarda

    2009-01-01

    El presente trabajo se encuentra inscripto en la investigación Vicisitudes del lazo amoroso en la época (en el Gran La Plata). En ella, nuestro rasgo de investigación -a partir de entrevistas realizadas a sujetos detenidos en unidades penitenciarias-, será establecer algunas coordenadas para pensar que los signos de la Declinación del Nombre del Padre deben leerse en la transformación del registro del amor, dejando por fuera el registro que más desarrollos ha tenido dentro del campo del psico...

  18. 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 ...

  19. 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 ...

  20. El suicidio en el adolescencia

    OpenAIRE

    Gil Encinas, María

    2013-01-01

    Se intenta explicar en qué consiste el suicidio en la adolescencia. Para ello, es importante describir qué es el suicidio y qué factores participan en la conducta de suicidio, o dicho de otra forma, cuáles son las causas que llevan a un adolescente a suicidarse. También se aborda la prevención de la conducta suicida en adolescentes

  1. El vitalhumanismo

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Polo Santillán

    2011-05-01

    Full Text Available Darío Botero Uribe (1938-2010[1] fue profesor emérito de la Universidad de Colombia, cuenta con una vasta producción filosófica, unida por un proyecto original denominado Vitalismo Cósmico. Entre sus obras podemos mencionar: La voluntad de poder de Nietzsche (1992, con cuatro ediciones, Teoría social del derecho (1993, con cuatro ediciones, Manifiesto del pensamiento latinoamericano (1993, con cinco ediciones, El derecho a la utopía (1994, con cinco ediciones, Vida, ética y democracia (1995, con dos ediciones[2], Vitalismo Cósmico (2002, Discurso sobre el humanismo (2004, entre otros. Un rasgo de su actividad filosófica ha sido lograr constituir una escuela filosófica, que pretende mirar críticamente las filosofías actuales para poder formular una nueva propuesta, el Vitalismo Cósmico, desde el contexto latinoamericano. En este artículo queremos presentar sus principales tesis de la siguiente manera: la visión del hombre, la propuesta humanista y la ética vitalista que de ahí se genera. Finalmente, reflexionar sobre algunos aspectos problemáticos de su humanismo. [1] Conocí al maestro Darío Botero el año 2005, en el 1er. Encuentro Nacional por la Vida, que él organizó en Bogotá. Sin duda, él era expresión de su propia filosofía vitalista.   [2] Los datos sobre el número de ediciones han sido tomados del artículo de Damián Pachón (2008.

  2. El CRIT: el renacer Pijao

    Directory of Open Access Journals (Sweden)

    Daniel Santiago Roldán Zarazo

    2016-01-01

    Full Text Available El artículo reconstruye el periodo histórico previo a la creación del Consejo Regional Indígena del Tolima (CRIT, organización que agrupa una gran variedad de cabildos y colectivos principalmente del Sur del Tolima. Así, desde el marco de coyunturas y estructuras se desarrolla un análisis documental y de prensa que evidencian los imaginarios, disputas y enfrentamientos de los indígenas en la región. El periodo se divide en cuatro momentos: (1 las condiciones estructurales, políticas y económicas que atravesaba el país y los indígenas en la época; posteriormente (2, se concentra en quienes le conformaban, sus posibilidades y restricciones de movilización; en tercera medida (3 se exponen los debates, marcos de acción, estructuras de movilización y las conclusiones llegadas en los encuentros del movimiento; por último (4 se recogen los elementos generales que arroja el periodo estudiado junto con elementos de discusión y aportes a la teoría e historia política.

  3. Synthesis of the lithium metatitanate, Li{sub 2}TiO{sub 3}, by the modified combustion method; Sintesis del metatitanato de litio, Li{sub 2}TiO{sub 3}, por el metodo modificado de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, D.; Bulbulian, S. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Pfeiffer, H. [IIM-UNAM, A.P. 70-360, 04510 Mexico D.F. (Mexico)]. e-mail: sb@nuclear.inin.mx

    2005-07-01

    A modified combustion method to obtain Li{sub 2}TiO{sub 3} it was used, a compound to be used in fusion reactors like tritium generator material. To obtain Li{sub 2}TiO{sub 3} were proven different molar ratios of lithium hydroxide (LiOH), titanium oxide (TiO{sub 2}) and urea (CO(NH{sub 2}){sub 2}), as well as different heating temperatures (550, 650 and 750 C). The characterization of the products it was carried out using X-ray diffraction, Scanning electron microscopy and Thermal gravimetric analysis. The sample prepared with a molar ratio Li: Ti: urea = 2.75: 1: 3 was the one that presented as only product the Li{sub 2}TiO{sub 3}. The particle size and the morphology found in the Li{sub 2}TiO{sub 3}, showed similar particle size and morphology to the TiO{sub 2} used as precursor. (Author)

  4. El Relevo

    OpenAIRE

    Lausent-Herrera, Isabelle

    2014-01-01

    Un Japón vencido no era en absoluto de la conveniencia de los Estados Unidos, que estaban decididos a utilizarlo como escudo asiático en la guerra de Corea. Había entonces que ayudar a reconstruir y rehabilitar su economía, renovando los intercambios con el exterior y organizando su reinserción en el seno de las naciones libres. Desde 1949, los Estados Unidos —que retenían aún en sus campos, esta vez involuntariamente, a más de 300 peruanos japoneses —, intervinieron a fin de restablecer las ...

  5. Characterization of modified clinoptilolite

    International Nuclear Information System (INIS)

    Novosad, J.; Jandl, J.; Woollins, J.D.

    1992-01-01

    Samples of clinoptilolite were modified using insoluble hexacyanoferrate from aqueous solution. The modified samples were characterized by elemental analysis, powder X-ray diffraction, solid state NMR and vibrational spectroscopy. The sorption properties of modified clinoptilolite were studied, too. Higher affinity for 137 Cs sorption in comparison with the natural clinoptilolite has been proved. (author) 5 refs.; 3 figs.; 2 tabs

  6. Independent dose calculation in IMRT for the Tps Iplan using the Clarkson modified integral; Calculo independiente de dosis en IMRT para el TPS Iplan usando la integral modificada de Clarkson

    Energy Technology Data Exchange (ETDEWEB)

    Adrada, A.; Tello, Z.; Garrigo, E.; Venencia, D., E-mail: jorge.alberto.adrada@gmail.com [Instituto Privado de Radioterapia, Obispo Oro 423, X5000BFI Cordoba (Argentina)

    2014-08-15

    Intensity-Modulated Radiation Therapy (IMRT) treatments require a quality assurance (Q A) specific patient before delivery. These controls include the experimental verification in dose phantom of the total plan as well as dose distributions. The use of independent dose calculation (IDC) is used in 3D-Crt treatments; however its application in IMRT requires the implementation of an algorithm that allows considering a non-uniform intensity beam. The purpose of this work was to develop IDC software in IMRT with MLC using the algorithm proposed by Kung (Kung et al. 2000). The software was done using Matlab programming. The Clarkson modified integral was implemented on each flowing, applying concentric rings for the dose determination. From the integral of each field was calculated the dose anywhere. One time finished a planning; all data are exported to a phantom where a Q A plan is generated. On this is calculated the half dose in a representative volume of the ionization chamber and the dose at the center of it. Until now 230 IMRT planning were analyzed carried out ??in the treatment planning system (Tps) Iplan. For each one of them Q A plan was generated, were calculated and compared calculated dose with the Tps, IDC system and measurement with ionization chamber. The average difference between measured and calculated dose with the IDC system was 0.4% ± 2.2% [-6.8%, 6.4%]. The difference between the measured and the calculated doses by the pencil-beam algorithm (Pb) of Tps was 2.6% ± 1.41% [-2.0%, 5.6%] and with the Monte Carlo algorithm was 0.4% ± 1.5% [-4.9%, 3.7%]. The differences of the carried out software are comparable to the obtained with the ionization chamber and Tps in Monte Carlo mode. (author)

  7. MODIFIED TECHNIQUE OF TOTAL LARYNGECTOMY

    Directory of Open Access Journals (Sweden)

    Predrag Spirić

    2010-12-01

    Full Text Available Surgical technique of total laryngectomy is well presented in many surgical textbooks. Essentially, it has remained the same since Gluck an Soerensen in 1922 described all its details. Generally, it stresses the U shape skin incision with releasing laryngeal structures and removing larynx from up to down. Further, pharyngeal reconstruction is performed with different kinds of sutures in two or more layers and is finished with skin suture and suction drainage. One of worst complications following this surgery is pharyngocutaneous fistula (PF. Modifications proposed in this this article suggests vertical skin incision with larynx removal from below upwards. In pharyngeal reconstruction we used the running locked suture in submucosal plan with „tobacco sac“ at the end on the tongue base instead of traditional T shaped suture. Suction drains were not used.The aim of study was to present the modified surgical technique of total laryingectomy and its impact on hospital stay duration and pharyngocutanous fistula formation. In this randomized study we analyzed 49 patients operated with modified surgical technique compared to 49 patient operated with traditional surgical technique of total laryngectomy. The modified technique of total laryngectomy was presented. Using modified technique we managed to decrease the PF percentage from previous 20,41% to acceptable 8,16% (p=0,0334. Also, the average hospital stay was shortened from 14,96 to 10,63 days (t =-2.9850; p=0.0358.The modified technique of total laryngectomy is safe, short and efficient surgical intervention which decreases the number of pharyngocutaneos fistulas and shortens the hospital stay.

  8. Estresse no trabalho em agentes dos centros de atendimento socioeducativo do Rio Grande do Sul Estrés en el trabajo en agentes en los centros de atención socioeducativa de Rio Grande do Sul Job stress in agents at the socio-educational service centers in the state of Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Patrícia Bitencourt Toscani Greco

    2013-03-01

    Full Text Available Estudo que teve por objetivo verificar a associação entre estresse no trabalho, características sociodemográficas, laborais, hábitos e condições de saúde dos agentes socioeducadores do Rio Grande do Sul, Brasil. Trata-se de um estudo transversal com 381 agentes dos Centros de Atendimento Socioeducativo do Rio Grande do Sul. Utilizou-se a versão brasileira da Job Stress Scale, para avaliação do estresse no trabalho. Foram classificados, em situação de alta exigência no trabalho, 19,2% dos agentes. Mostraram-se associados ao estresse no trabalho: necessidade de acompanhamento psicológico, falta de tempo para lazer, turno diurno de trabalho, insatisfação com o local de trabalho, necessidade de afastamento do trabalho, por problemas de saúde, e escala de trabalho insuficiente. Há necessidade de buscar melhores condições de trabalho e a efetivação de um Serviço de Saúde do Trabalhador atuante, no sentido de minimizar os efeitos das demandas psicológicas no trabalho do agente socioeducador.El estudo tenía el objetivo de verificar la asociación entre estrés en el trabajo, rasgos sociodemográficos, laborales, hábitos y condiciones de salud de los agentes socioeducadores de Rio Grande do Sul, Brasil. Es un estudio transversal con 381 agentes de Centros de Atención Socioeducativa de Rio Grande do Sul. Se utilizó la versión brasileña de Job Stress Scale para evaluación de estrés en el trabajo. El 19, 2% de los agentes se clasificó en situación de alta exigencia laboral. Se mostraron asociadas al estrés en el trabajo: necesidad de acompañamiento psicológico, falta de tiempo para el ocio, tiempo diurno de trabajo, insatisfacción con el lugar de trabajo, necesidad de alejamiento del trabajo por problemas de salud y escala de trabajo insuficiente. Existe la necesidad de buscar mejores condiciones de trabajo y la efectuación de un Servicio de Salud del Trabajador actuante, para minimizar los efectos de las demandas

  9. A enfermeira no cuidado aos pacientes submetidos ao eco-stress farmacológico: implicações para a prática clínica El rol de la enfermera en la atención de pacientes sometidos al ecoestrés farmacológico: implicaciones en la práctica clínica Nursing care for patients undergoing pharmacological stress echocardiography: implications for clinical practice

    Directory of Open Access Journals (Sweden)

    Marta Georgina Oliveira de Goes

    2012-06-01

    Full Text Available Estudo que teve por objetivos identificar os sinais e sintomas prévios e os ocorridos durante o exame de eco-stress farmacológico, descrever a atuação da enfermeira e os pressupostos para o cuidado de enfermagem na realização desse exame. Trata-se de pesquisa exploratório-descritiva, em uma unidade diagnóstica cardiológica de um hospital universitário de Porto Alegre. Foram estudadas, retrospectivamente, 246 fichas de registros de pacientes submetidos ao eco-stress, com quatro diferentes protocolos farmacológicos. A análise estatística apontou que os sinais e sintomas associados ao tipo de fármaco utilizado durante o exame foram, prevalentemente: angina típica, dor precordial, cansaço, cefaleia e extrassístoles. Esses resultados propiciaram conhecer melhor o eco-stress farmacológico, de forma a instrumentalizar a enfermeira para a prática clínica, tanto na organização da unidade para a realização do exame quanto no cuidado ao paciente submetido ao mesmo.Estudio que tuvo por objetivos, identificar los signos y síntomas previos, y los ocurridos durante el examen de ecoestrés farmacológico, y describir el rol de la enfermera y los fundamentos para los cuidados de enfermería durante la realización de este examen. Es un trabajo descriptivo, realizado en una unidad diagnóstica cardiológica de un hospital universitario de Porto Alegre, RS. Fueron estudiados, de forma retrospectiva, 246 expedientes médicos de pacientes sometidos al ecoestrés, con cuatro diferentes protocolos farmacológicos. El análisis estadístico demostró que los signos y síntomas fueron asociados al tipo de fármaco utilizado durante el examen, y estos fueron: angina típica, dolor precordial, cansancio, cefalea y extrasístoles. Estos resultados ayudaron a conocer mejor el ecoestrés farmacológico y preparar mejor a la enfermera para la práctica clínica, tanto en la organización del servicio donde se realizaron los exámenes como en los

  10. La infertilidad, el maternaje frustrado

    Directory of Open Access Journals (Sweden)

    Ignacio González Labrador

    2002-06-01

    Full Text Available Se realizó un acercamiento conceptual a la influencia que la infertilidad humana puede ejercer sobre el proceso llamado maternaje, y cómo se le puede modificar, así como también conocer su influencia en la sexualidad femenina.A conceptual approach to the influence that human infertility may exert on a process called manternaje, how it can be modified and its influence on female sexuality are all presented in this paper.

  11. La infertilidad, el maternaje frustrado

    OpenAIRE

    González Labrador, Ignacio

    2002-01-01

    Se realizó un acercamiento conceptual a la influencia que la infertilidad humana puede ejercer sobre el proceso llamado maternaje, y cómo se le puede modificar, así como también conocer su influencia en la sexualidad femenina.A conceptual approach to the influence that human infertility may exert on a process called manternaje, how it can be modified and its influence on female sexuality are all presented in this paper.

  12. EL HOMBRECITO

    Directory of Open Access Journals (Sweden)

    Julio E. Sánchez Arbelaez

    1981-10-01

    Full Text Available

    El jefe de la consulta externa, es magro y ascético. Al mirarlo caminar por las calles, uno no puede menos de pensar que es médico. Y chapado a la antigua. También tiene una terminologia muy especial:

    "El indio y el tornillo son incompatibles" es su estribillo favorito. Nadie sabia realmente qué
    queria decir con esto, hasta cuando se demostró palpablemente.
    Todo comenzó una tarde, cuando la rutina de urgencias se vio interrumpida por la llegada de un cortejo campesino.
    A primera vista parecia que se trataba de un herido, porque lo bajaron de un Ford modelo 46 negro, lo que en policlinica se conocia como fatidicos carros de la violencia, para no olvidar que los pájaros del occidente se transportaban siempre en ellos.

    Pero no, era un hombrecito, de escasos treinta años pero que aparentaba cincuenta. Los dientes cariados no dejaban duda acerca de la desnutrición y las palmas y plantas llenas de callosidades evidenciaban la honradez.
    Respiraba apenas fatigosamente; los ojos entrecerrados no permitian siquiera el examen de las pupilas, un color azuloso se extendia por las comisuras labiales y los surcos nasogenianos que aleteaban dificultosamente.
    De vez en cuando un súbito espasmo de efímera duración estremecia toda su magra arquitectura. Unas manchas pequeñitas como rosetas cubrian toda la superficie cutánea que dejaba al descubierto la camisa deshilachada y el pantalón de dril, mojado éste por un liquido sanguinolento cuyo acre olor no dejaba duda de su procedencia.

    El interno, Del Valle, acucioso como siempre preguntó:
    -¿Qué le pasó al hombrecito?
    -Le picó una culebra, dijo el que parecia ser cabeza de familia.
    -¿Hace cuánto?...

  13. 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 ...

  14. 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: ...

  15. 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 ...

  16. El Espiritismo

    Directory of Open Access Journals (Sweden)

    Adolfo de Francisco Zea

    2001-04-01

    Full Text Available

    Hablar sobre espiritismo en Bogotá podría entenderse por algunos, como simplemente hablar sobre asuntos extraños ya pasados de moda; asuntos, además, esotéricos o teñidos de magia; o carentes quizás de la necesaria seriedad que deben tener estos estudios. Sin embargo, el tema no ha dejado de tener su importancia y tiene además para nosotros; un indudable interés histórico por los desarrollos que en ese campo se llevaron a cabo en los Estados Unidos y en Europa en la segunda mitad del siglo pasado y a comienzos del presente, a los cuales no fue ajeno nuestro país.

    En efecto, en las primeras décadas del siglo, algunos de nuestros compatriotas, muchos de ellos con indudable buena fe y adecuada preparación filosófica o científica, se empeñaron en indagar las posibles causas de ciertos hechos psicológicos, al parecer misteriosos, sobre los cuales, como lo expresara Luis Zea Uribe, “acumula la ignorancia las más diversas explicaciones“.

    Quiero abordar el tema con la máxima objetividad de que sea capaz. Señalar los hechos históricos más sobresalientes con relación a estos asuntos y guardar el respeto debido a los espiritistas que consideran realidad incontrovertible la comunicación de los vivos con los muertos en el curso de sesiones espiritistas. Tendría igual respeto por aquellos que no creen en la hipótesis espiritualista pero que ofrecen explicaciones alternativas acerca de las causas de los fenómenos de la médiumnidad, explicaciones en las que no se acepta la realidad de las comunicaciones entre vivos y muertos a través de los médium. No es mi intención presentar una posición personal frente a los hechos, ni intentar convencer a ustedes sobre la verdad de una u otra de estas hipótesis.

    Tampoco me referiré a los fraudes y engaños cometidos a favor o en contra del espiritismo, porque ellos escapan a un enfoque intelectual y científico de los hechos. Pienso más conveniente y adecuado

  17. The serotonin transporter and early life stress : Translational perspectives

    NARCIS (Netherlands)

    Houwing, Danielle J; Buwalda, Bauke; Zee, van der Eddy; de Boer, Sietse F; Olivier, Jocelien D A

    2017-01-01

    The interaction between the serotonin transporter (SERT) linked polymorphic region (5-HTTLPR) and adverse early life stressing (ELS) events is associated with enhanced stress susceptibility and risk to develop mental disorders like major depression, anxiety, and aggressiveness. In particular, human

  18. Efectos crónicos de un programa de alargamiento pasivo sobre los valores de la presión arterial sanguinea y el estrés en adultos con hipertensión arterial. Chronics effects of a passive stretching program on the blood pressures and stress levels of hypertensions adults.

    Directory of Open Access Journals (Sweden)

    Bezerra da Silva, Elirez

    2007-07-01

    Full Text Available ResumenEl objetivo de este estudio fue analizar los efectos crónicos de un programa de alargamiento pasivo sobre la presión arterial sanguínea y estrés en adultos con hipertensión arterial. Participaron de este estudio, 12 personas de ambos sexos, con edad media de 52,12±5,5 años, sedentarios y con diagnóstico médico de hipertensión arterial. Las variables recolectadas para la realización de la investigación fueron la presión arterial sanguínea y el estrés de dichas personas. El tratamiento estadístico fue realizado por análisis descriptivos y análisis de inferencia. Los tests estadísticos de naturaleza comparativa fueron realizado a través de los análisis de variancia (ANOVA one-way yuxtapuesto con el test de Post hoc de Tukey, para identificar las posibles diferencias entre los datos de la presión arterial sanguínea. El test de Kruskal-Wallis fue usado para comparar las respuestas del cuestionario de estrés. Fue admitido el valor de pAbstractPurpose of this study was verifier the chronics effects of passive stretching programs on the stress and blood pressure levels of adults with arterial hypertension. 12 subjects of both gender, age average of 52,12 52,12±5,52 year, sedentary and with screening of arterial hypertension, volunteered to participate this study. The variables identified to the conduction of the respective study were the blood pressure, physical activity level and stress of the subjects. Statistic treatment was compost for descriptive and inferential analysis across of the variance analysis test (ANOVA two-way, concomitant with Post hoc test of Tukey, to estimate the differences in the average of the variables during the diverse moments of test. Kuskal-Wallis test was realized to compare the replies of the stress questionnaire. A value of p

  19. Work-related social support modulates effects of early life stress on limbic reactivity during stress.

    Science.gov (United States)

    Leicht-Deobald, Ulrich; Bruch, Heike; Bönke, Luisa; Stevense, Amie; Fan, Yan; Bajbouj, Malek; Grimm, Simone

    2017-12-15

    Early life stress (ELS) affects stress- reactivity via limbic brain regions implicated such as hippocampus and amygdala. Social support is a major protective factor against ELS effects, while subjects with ELS experience reportedly perceive less of it in their daily life. The workplace, where most adults spend a substantial amount of time in their daily lives, might serve as a major resource for social support. Since previous data demonstrated that social support attenuates stress reactivity, we here used a psychosocial stress task to test the hypothesis that work-related social support modulates the effects of ELS. Results show decreased amygdala reactivity during stress in ELS subjects who report high levels of work- related social support, thereby indicating a signature for reduced stress reactivity. However, this effect was only observable on the neural, but not on the behavioral level, since social support had no buffering effect regarding the subjective experience of stress in daily life as well as regarding feelings of uncontrollability induced by the stress task. Accordingly, our data suggest that subjects with ELS experiences might benefit from interventions targeted at lowering their subjective stress levels by helping them to better perceive the availability of social support in their daily lives.

  20. el bachillerato

    Directory of Open Access Journals (Sweden)

    César Silva Montes

    2006-01-01

    Full Text Available Alcanzar la calidad educativa en el bachillerato mexicano ha sido una preocupación desde 1995. Congruente con las tendencias mundiales, la Dirección General del Bachillerato (DGB impulsa programas de actualización docente para adaptar la práctica pedagógica a las demandas del mercado laboral y difundir el conocimiento tecnológico. En la etapa mundial de globalización, los referentes de la calidad en educación provienen de la empresa y sus conceptos forman un paradigma que, para la DGB, se sintetiza en la planeación estratégica. Nociones como cliente del sistema educativo y las escuelas como prestadoras de servicios, son parte de la cotidianidad en las Preparatorias Federales por Cooperación.

  1. el constructivismo

    Directory of Open Access Journals (Sweden)

    Ana María Cerezo-Bautista

    2008-01-01

    Full Text Available Los supuestos teóricos de los autores de enfermería han sido realizados con base en la realidad percibida, y en la práctica en muchos casos; es por esto que en la práctica cotidiana del cuidado puede verse que múltiples conceptos de la disciplina de enfermería son aplicados por algunos profesionales sin tener conciencia de quién los ha propuesto. El presente artículo tiene como objetivo analizar aspectos relacionados con el cuidado de enfermería integral a los pacientes en estado crítico, sometidos a ventilación mecánica, a la luz de los conceptos disciplinares propuestos en el modelo de relación de persona a persona de Joyce Travelbee. Se realizó observación participante en UCI de 80 horas de duración, durante la cual se analizó el desarrollo de la práctica diaria del cuidado de las enfermeras que estaban de turno. Los datos de la observación fueron confrontados con los propuestos teóricos de Travelbee y otros autores, lo que permitió ver que aun cuando los enfermeros no tengan conocimiento acerca de las teorías de enfermería, su práctica de cuidado puede estar en consonancia con ellas, no en vano las teorías son formuladas, en muchos casos, con base en eventos prácticos.

  2. El factoring

    Directory of Open Access Journals (Sweden)

    Alberto Rosenthal

    2015-04-01

    Full Text Available RESUMEN Se presenta la segunda parte del artículo aparecido en  el número 6 de la revista EAN. Su contenido es complementario a lo expuesto en dicho número, en está aparecen las ventajas del factoring, conveniencias, limitaciones así como la forma  de efectuar un factor en Colombia,  su necesidad, incidencia económica, etc.

  3. El Viaje

    Directory of Open Access Journals (Sweden)

    Pedro Martínez Sanz

    2009-06-01

    Full Text Available Las exploraciones hidrográficas y geográficas siempre han sido necesarias para Inglaterra,muy consciente de su condición insular. El marino Robert Fitz Roy participa en dos de ellas incorporando a Charles Darwin en la segunda, quien a los 22 años era bachiller en Teología, Filosofía y Artes en Cambridge. Además se había preparado en geología e historia natural.Gran observador y capaz de llegar a conclusiones generales desde los detalles visibles. Ése viaje duró casi 5 años, tanto por mar como por las exploraciones por tierra que efectúo Darwin. Reconoció el bosque húmedo, los glaciares y fue testigo de erupciones volcánicas, maremotos y terremotos. En las Islas Galápagos hizo sus observaciones zoológicas que dieron base a sus postulados sobre el origen de las especies y la supervivencia de las más aptas. De vuelta en Inglaterra sus observaciones serán maduradas por él y sus seguidores, por décadas, tarea que continúa en la actualidad.

  4. El Cuajo

    Directory of Open Access Journals (Sweden)

    Ramírez S. Carlos A.

    1942-08-01

    Full Text Available Se conoce vulgarmente por cuajo, una substancia que tiene la propiedad de coagular la leche y se presenta corrientemente en polvo o líquida. La leche también se coagula por la acción de un ácido, sea éste agregado (jugo de limón, ácido clorhídrico etc. o bien por el conseguido a consecuencia del trabajo de los microorganismos, con los cuales se contamina apenas es extraída u ordeñada. El cuajo o quimosina fermento también conocido como Lab, se le encuentra en mayor cantidad, en la división del estómago de los terneros conocida como cuajar y cuando éstos están lactando, es decir que no ingieren otro alimento que no sea la leche. Por este motivo, cuando se precisa el fermento en las explotaciones rurales, sacrifican torneros y preparan un compuesto rico en cuajo, llamado manzanilla o cuajo casero.

  5. On Modified Bar recursion

    DEFF Research Database (Denmark)

    Oliva, Paulo Borges

    2002-01-01

    Modified bar recursion is a variant of Spector's bar recursion which can be used to give a realizability interpretation of the classical axiom of dependent choice. This realizability allows for the extraction of witnesses from proofs of forall-exists-formulas in classical analysis. In this talk I...... shall report on results regarding the relationship between modified and Spector's bar recursion. I shall also show that a seemingly weak form of modified bar recursion is as strong as "full" modified bar recursion in higher types....

  6. El concepto de igualdad ante el mercado

    Directory of Open Access Journals (Sweden)

    CARLOTA SOLÉ

    1996-01-01

    Full Text Available Después de examinar el concepto de igualdad desde el punto de vista sociólogico, en la realidad social del capitalismo avanzado y en el superado socialismo real, se analiza críticamente el papel del estado como mecanismo igualitario o redistribuidor (de rentas, de privilegios, de recursos, de habilidades, etc..

  7. El poder de la Iglesia imperial: el mito de Costantino y el papado romano

    Directory of Open Access Journals (Sweden)

    Ramón TEJA

    2010-02-01

    , there was stressed some parts of the emperor life in order to uphold the aims of the emergent authority of the Pope and its relationship with the aspirations of the bishops of Rome to be the heads of the Christian Church. This was the framework to locate the leyend of the Actus Silvestri that, in the ? century, gave to Silvestre (bishop of Rome in 314-335 a much more important role than he had ever had: the conversion of Constantine and the giving to the bishop of Rome primacy over the others. An ulterior narrative called Donatio Constantini, gave him a licit temporal authority on the territory of Italy. In medieval times, these two narratives were used by the Popes to strengthen the Pope supremacy over that of the emperors of the Holy Empire. In the ages of Renaissance, intellectuals linked to the Humanist movement pointed that those narratives were false, but this did not modify the Popes aims, whilst the protestant reformers of the North reconsidered the historical image of Constantine pointed the Popish adulteration of the emperor historical image. In spite of this, the Roman Church overcame those critics of the rationalism of the ages of Renaissance, Enlightenment and modern revolutions. Even nowadays the Pope keeps some power rituals and ceremonial inherited from the Roman emperors of the Ancient times.

  8. El Atlas del Bosque Nacional El Yunque

    Science.gov (United States)

    Maya Quiñones; Isabel K. Parés-Ramos; William A. Gould; Grizelle Gonzalez; Kathleen McGinley; Pedro. Ríos

    2018-01-01

    Esta publicación es un esfuerzo colaborativo entre el Instituto Internacional de Dasonomía Tropical y el Bosque Nacional El Yunque para proveer mapas y análisis de información espacial actualizados sobre una importante reserva natural en Puerto Rico y el único bosque tropical dentro del Sistema de Bosques Nacionales de los Estados Unidos. El Atlas del Bosque Nacional...

  9. El impacto de la reducción del estrés en la hipertensión esencial y las enfermedades cardiovasculares. (Impact of stress reduction on essential hypertension and cardiovascular disease).

    OpenAIRE

    David W. Orme-Johnson; Vernon A. Barnes

    2008-01-01

    ResumenSe ha considerado que el estrés contribuye a la patogénesis y la progresión de las enfermedades cardiovasculares (ECV). Se ha demostrado que la reducción del estrés mediante la Meditación Trascendental [Transcendental Meditation (TM)®] ha bajado los niveles de presión arterial (PA) y reducido el riesgo de ECV en adultos y adolescentes. Este artículo repasa los resultados que sugieren el impacto beneficioso de la TM en reducir la PA en adultos hipertensos en reposo y en adolescentes pr...

  10. El periodista, entre el Poder

    Directory of Open Access Journals (Sweden)

    JL Dader

    2014-10-01

    Full Text Available El periodismo se debate, desde sus orígenes, entre la reproducción servil de versiones interesadas o la distorsión de propio cuño, por conocimiento insuficiente de una realidad que sólo puede entrever. Los poderes que amenazan la independencia periodística no han hecho más que crecer o aumentar su habilidad con el paso del tiempo. Surgido como ‘oficio de esclavos’ en la época romana, muchos indicadores actuales parecen retornarle al punto de partida: relaciones públicas estratégicas a gran escala, auge de los ‘spin doctors’, extorsión descarnada en las democracias más débiles y populismo de las redes sociales, entre otros. Todo ello, unido o alentado por la degradación interna y el desaliento de la propia institución periodística incapaz de distanciarse de todas esas fuerzas. Su respuesta no puede ser de alianza o competencia con los poderes que la circundan, sino de hábil distanciamiento para moverse entre todos ellos sin dejar de ejercer la vigilancia que los ciudadanos siguen necesitando de su ejercicio profesional.

  11. el ocaso y el porvenir

    Directory of Open Access Journals (Sweden)

    Laura Regil Vargas

    2004-01-01

    Full Text Available Este artículo inicia con un breve estudio de los signos vitales de la difusión dentro de la universidades. Cada vez es más frecuente encontrar a la difusión cultural en las universidades públicas detenida frente a la disyuntiva entre el debilitamiento y el porvenir, la agonía y la reactivación. Quienes se interesen en dar pasos que permitan transformar esta encrucijada, como punto de partida, encontrarán aquí pautas para la reflexión, orientadas a la puesta en marcha de acciones que apoyen y fortalezcan esta actividad, siempre mencionada como sustantiva, aunque, en la práctica, ubicada por debajo de la investigación y la docencia. En suma, es una propuesta para crear el porvenir de la difusión, a partir del análisis, la crítica constante y la evaluación.

  12. Modified Allergens for Immunotherapy.

    Science.gov (United States)

    Satitsuksanoa, Pattraporn; Głobińska, Anna; Jansen, Kirstin; van de Veen, Willem; Akdis, Mübeccel

    2018-02-16

    During the past few decades, modified allergens have been developed for use in allergen-specific immunotherapy (AIT) with the aim to improve efficacy and reduce adverse effects. This review aims to provide an overview of the different types of modified allergens, their mechanism of action and their potential for improving AIT. In-depth research in the field of allergen modifications as well as the advance of recombinant DNA technology have paved the way for improved diagnosis and research on human allergic diseases. A wide range of structurally modified allergens has been generated including allergen peptides, chemically altered allergoids, adjuvant-coupled allergens, and nanoparticle-based allergy vaccines. These modified allergens show promise for the development of AIT regimens with improved safety and long-term efficacy. Certain modifications ensure reduced IgE reactivity and retained T cell reactivity, which facilities induction of immune tolerance to the allergen. To date, multiple clinical trials have been performed using modified allergens. Promising results were obtained for the modified cat, grass and birch pollen, and house dust mite allergens. The use of modified allergens holds promise for improving AIT efficacy and safety. There is however a need for larger clinical studies to reliably assess the added benefit for the patient of using modified allergens for AIT.

  13. Water Stress Projection Modeling

    Science.gov (United States)

    2016-09-01

    water consumption stress in coming decades is electricity generation in two surrounding counties, El Paso and Doña Ana, which are expected to...better able to predict and prepare for a changing climate. Army installations will be affected by climate change. It behooves the Army to understand...stationing analysis, the resources ex- amined were: a. Training land b. Energy ( electricity and natural gas) c. Water and wastewater treatment and solid

  14. 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 ...

  15. Estresse ocupacional: avaliação de enfermeiros intensivistas que atuam no período noturno Estrés laboral: evaluación de enfermeros intensivistas que trabajan en el periodo nocturno Occupational stress: evaluation of intensive care nurses who work at nighttime

    Directory of Open Access Journals (Sweden)

    Gelena Lucinéia Gomes da Silva Versa

    2012-06-01

    Full Text Available Estudo descritivo, transversal, que teve como objetivo avaliar o nível de estresse de enfermeiros intensivistas do período noturno. Aplicou-se a Escala Bianchi de Stress em 26 (100% enfermeiros de cinco hospitais. Na análise dos dados, utilizou-se o teste Qui-quadrado de Pearson e constatou-se que o estresse entre enfermeiros da instituição pública (3,36 pontos e privada (3,02 pontos se classificou em nível mediano e que não houve relevância estatística (p=0,90 à sua ocorrência, conforme o tipo de instituição. Os domínios que mais contribuíram ao acontecimento de estresse foram: condições de trabalho (labor noturno, setor crítico e fechado, gravidade do paciente e atividades gerenciais associadas à assistência direta. Concluiu-se que o ambiente laboral se associou positivamente ao estresse em enfermeiros do turno noturno e que o seu aparecimento e efeitos podem ser minimizados por meio de melhorias na estrutura e na organização dos locais onde atuam.Estudio descriptivo, transversal, tuvo como objetivo evaluar el nivel de estrés de los enfermeros intensivistas, del período nocturno. Se aplicó escala de estrés Bianchi en 26 (100% enfermeros de cinco hospitales. Para análisis de datos, se utilizó el Chi-cuadrado de Pearson y resultó: estrés entre enfermeros de institución pública (3,36 puntos y privada (3,02 puntos se clasificó a nivel medio y no hubo significación estadística (p = 0,90 para el estrés en función del tipo de institución. Las áreas que más contribuyeron al acontecimiento de estrés fueron: condiciones de trabajo (nocturno, sector crítico y cerrado; gravedad del paciente; actividades de gestión asociadas a la atención. Se concluyó que el lugar de trabajo se asoció positivamente al estrés en los enfermeros que trabajan en el período nocturno y que, su aparición y efectos pueden ser minimizados por medio de mejoras en la estructura y organización de los locales donde act

  16. El Humanismo

    Directory of Open Access Journals (Sweden)

    Carla Cordua

    2013-10-01

    Full Text Available Las humanidades son una creación del humanismo. Pero “humanismos” hubo varios, antes del que nos interesa aquí, algunos ya en la Edad Media y otros después de ella; entre los anteriores tuvo lugar un humanismo famoso en la corte de Carlomagno pero no produjo efectos duraderos fuera de esta corte. Para asociarlo a la situación presente no me referiré sino al humanismo del Renacimiento italiano, el que genera en los siglos XV y XVI los llamados studia humanitatis, origen de nuestras “humanidades”.

  17. The Modified Embedded Atom Method

    Energy Technology Data Exchange (ETDEWEB)

    Baskes, M.I.

    1994-08-01

    Recent modifications have been made to generalize the Embedded Atom Method (EAM) to describe bonding in diverse materials. By including angular dependence of the electron density in an empirical way, the Modified Embedded Atom Method (MEAM) has been able to reproduce the basic energetic and structural properties of 45 elements. This method is ideal for examining interfacial behavior of dissimilar materials. This paper explains in detail the derivation of the method, shows how parameters of MEAM are determined directly from experiment or first principles calculations, and examine the quality of the reproduction of the database. Materials with fcc, bcc, hcp, and diamond cubic crystal structure are discussed. A few simple examples of the application of the MEAM to surfaces and interfaces are presented. Calculations of pullout of a SiC fiber in a diamond matrix as a function of applied stress show nonuniform deformation of the fiber.

  18. El Salvador.

    Science.gov (United States)

    1987-11-01

    The Central American republic of El Salvador lies on the Pacific with a south coast between Guatemala and Honduras. The climate rises from tropical maritime along the coast to subtropical hill and valley strip to a mountainous interior. The population consists of 98% Mestizo and 10% Indian, totaling 5.1 million, growing at 2.4 annually. Literacy varies from 40-60%; the infant mortality rate is 71/1000, and the life expectancy is 63-66 years. The economy is based on agricultural products as coffee, sugar and cotton and light industry such as textiles and petroleum refining, but due to political unrest, the 1986 earthquake, and fluctuating commodity prices, inflation runs about 36% and the per capita income is $700. El Salvador takes pride in its independence since 1821, but its history is marked by revolutions and control of government, military and ecclesiastical power by "the fourteen families." The current democratic government, considered to be the result of a fair election, is undertaking land reform and participates in the Central American peace process.

  19. El IDRC en Uruguay

    International Development Research Centre (IDRC) Digital Library (Canada)

    Comercio y crecimiento económico ... el crecimiento en beneficio de los pobres. Gestión costera ... actividad humana y erosión en el Río de la. Plata, el ... CENTRO INTERNACIONAL DE INVESTIGACIONES PARA EL DESARROLLO. El IDRC ...

  20. El Diccionario entre el fetichismo y el prejuicio

    Directory of Open Access Journals (Sweden)

    Hernán Rodríguez Castelo

    2015-01-01

    Full Text Available En español tenemos el Diccionario. Así, con el determinativo y la mayúscula, que lo dan por único en su clase. “No está en el Diccionario”, se dice y es por cualquiera entendido. Ofrece una breve síntesis histórica del origen de éste con la creación de la Academia Española (06- 1713 Comenta la importancia que el diccionario tiene para el ejercicio del periodismo. Se refiere al prejuicio y al fetichismo, respecto al DRAE, ambos ciegos e irracionales.

  1. Observational tests of modified gravity

    International Nuclear Information System (INIS)

    Jain, Bhuvnesh; Zhang Pengjie

    2008-01-01

    Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the Universe. Modified gravity theories have richer observational consequences for large-scale structures than conventional dark energy models, in that different observables are not described by a single growth factor even in the linear regime. We examine the relationships between perturbations in the metric potentials, density and velocity fields, and discuss strategies for measuring them using gravitational lensing, galaxy cluster abundances, galaxy clustering/dynamics, and the integrated Sachs-Wolfe effect. We show how a broad class of gravity theories can be tested by combining these probes. A robust way to interpret observations is by constraining two key functions: the ratio of the two metric potentials, and the ratio of the gravitational 'constant' in the Poisson equation to Newton's constant. We also discuss quasilinear effects that carry signatures of gravity, such as through induced three-point correlations. Clustering of dark energy can mimic features of modified gravity theories and thus confuse the search for distinct signatures of such theories. It can produce pressure perturbations and anisotropic stresses, which break the equality between the two metric potentials even in general relativity. With these two extra degrees of freedom, can a clustered dark energy model mimic modified gravity models in all observational tests? We show with specific examples that observational constraints on both the metric potentials and density perturbations can in principle distinguish modifications of gravity from dark energy models. We compare our result with other recent studies that have slightly different assumptions (and apparently contradictory conclusions).

  2. Chemogenetic activation of the lateral hypothalamus reverses early life stress-induced deficits in motivational drive.

    Science.gov (United States)

    Campbell, Erin J; Mitchell, Caitlin S; Adams, Cameron D; Yeoh, Jiann Wei; Hodgson, Deborah M; Graham, Brett A; Dayas, Christopher V

    2017-10-01

    Altered motivated behaviour is a cardinal feature of several neuropsychiatric conditions including mood disorders. One well-characterized antecedent to the development of mood disorders is exposure to early life stress (ELS). A key brain substrate controlling motivated behaviour is the lateral hypothalamus (LH). Here, we examined the effect of ELS on LH activation and the motivation to self-administer sucrose. We tested whether chemogenetic activation of LH circuits could modify sucrose responding in ELS rats and examined the impact on LH cell populations. Male rat pups were maternally separated for 0 or 3 h on postnatal days 2-14. During adolescence, rats received bilateral injections of hM3D(Gq), the excitatory designer receptor exclusively activated by designer drugs, into LH. In adulthood, rats were trained to self-administer sucrose and tested under a progressive ratio schedule to determine their motivation for reward following injection with either vehicle or 5 mg/kg clozapine-N-oxide. Brains were processed for Fos-protein immunohistochemistry. ELS significantly suppressed lever responding for sucrose, indicating a long-lasting impact of ELS on motivation circuits. hM3D(Gq) activation of LH increased responding, normalizing deficits in ELS rats, and increased Fos-positive orexin and MCH cell numbers within LH. Our findings indicate that despite being susceptible to environmental stressors, LH circuits retain the capacity to overcome ELS-induced deficits in motivated behaviour. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  3. Flow stress anisotropy

    DEFF Research Database (Denmark)

    Winther, G.

    1996-01-01

    stress Variation in the rolling plane, which may be as high as 20%, are presented. The traditional Taylor model is applied to the data to account for the effect of texture. However, texture effects alone are not enough to explain all of the observed anisotropy. New models which take the combined effects...... of texture and deformation microstructure into account are presented. The models are based on the Taylor and Sachs models but modified with an anisotropic critical shear stress to account for the effect of the microstructure. The agreement between experimental data and model predictions is definitely better...

  4. Modified Nance palatal button

    Directory of Open Access Journals (Sweden)

    Nitin Arora

    2015-01-01

    Full Text Available This paper describes modified Nance palatal button by which problems encountered in the palatal region around the acrylic button during space closure and molar distalization can be minimized.

  5. Modified microdissection electrocautery needle

    OpenAIRE

    Singh, Virendra; Kumar, Pramod

    2014-01-01

    Electrocautery is routinely used in surgical procedures. The commercially available microdissection electrocautery needles are costly. To overcome this disadvantage, we have modified monopolar electrocautery tip to function as well as commercially available systems.

  6. el territorio

    Directory of Open Access Journals (Sweden)

    Mauricio Genet Guzmán Chávez

    2006-01-01

    Full Text Available En este artículo se exponen las implicacionesprácticas del discurso de la conservación de la biodiversidad en tanto política cultural. Trata de las formas como las comunidades, los moradores o los productores que viven en las áreas naturales protegidas pueden servirse del discurso de la biodiversidad en el proyecto de defensa de su territorio y su identidad cultural. Analiza y compara los casos de la reserva de la biosfera Los Tuxtlas, México, y de la reserva extractivista Chico Mendes, Brasil, áreas donde se discuten y se ponen en marcha diferentes alternativas y programas de manejo sustentable de los recursos naturales.

  7. Perturbações afectivo-emocionais em contexto de cuidados de saúde primários Depresión, ansiedad y estrés en el ámbito de la atención primaria de salud Depression, anxiety and stress in primary health care settings

    Directory of Open Access Journals (Sweden)

    João Apóstolo

    2011-03-01

    Full Text Available Contexto: O estudo desenvolve-se no contexto do projecto “Ansiedade e Stresse em Cuidados de Saúde Primários” integrado na linha de investigação “Bem-Estar, Saúde e Doença” da Unidade de Investigação da Escola superior de Enfermagem de Coimbra. Objectivos: Descrever os níveis de depressão, ansiedade e stresse de utilizadores de um centro de saúde urbano/rural, analisar as diferenças de género e a relação entre depressão, ansiedade, stresse e idade. Método: Estudo descritivo analítico, aplicando a versão portuguesa da DASS-21 a uma amostra consecutiva (n=441. Resultados: 40% a 50% dos indivíduos apresentam algum grau de perturbação afectivo-emocional (depressão, ansiedade ou stresse. Foram identificados níveis severos ou muito severos de ansiedade e stresse em mais de 17% dos indivíduos e níveis severos ou muito severos de depressão em 12%. As mulheres apresentam níveis médios de depressão, ansiedade e stresse mais elevados que os homens. Depressão, ansiedade e stresse estão forte e positivamente associados. Os indivíduos com idade superior a 65 anos apresentam valores de depressão, ansiedade e stresse mais elevados. Conclusão: Com base nos resultados, dever-se-ão desenvolver estratégias de intervenção individual e comunitária para a promoção da saúde mental e prevenção da doença, particularmente, junto das mulheres e da população idosa.Contexto: El estudio desarrollado en el contexto del proyecto “Ansiedad y Estrés en Cuidados de Salud Primarios” se llevó a cabo en el ámbito de la línea de investigación “Bienestar, Salud y Enfermedad” de la Unidad de Investigación de la Escuela Superior de Enfermería de Coimbra. Objetivos: Describir los niveles de depresión, ansiedad y estrés de los usuarios de un centro de salud urbano/rural, analizar las diferencias de género y la relación entre depresión, ansiedad, estrés y edad. Método: Estudio descriptivo analítico, aplicando la

  8. Seasonal cycle of hydrography in the Bab el Mandab region ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    The seasonal cycle of temperature - salinity variations in the Bab el Mandab region ... Sea water that flows into the Gulf of Aden is maximum during the winter and minimum during the summer. ..... stress the importance of both thermohaline and.

  9. El cuerpo, el gueto y el Estado penal

    Directory of Open Access Journals (Sweden)

    Loïc Wacquant

    2010-07-01

    Full Text Available Este artículo analiza el enfoque del autor sobre la etnografía, la teoría social, y la política del conocimiento a través de un diálogo que vuelve sobre su trayectoria intelectual y los vínculos analíticos entre sus investigaciones sobre el cuerpo, la marginalidad urbana comparada y el Estado penal. Resalta las conexiones prácticas y fundamentos epistemológicos detrás de sus principales proyectos de investigación, explica las distintas maneras en que se despliega el trabajo de campo de observación en cada uno de ellos, y examina el papel de los intelectuales en las sociedades avanzadas de la era del neoliberalismo hegemónico. Rechazando tanto el empirismo de Hume como el neo-cognitivismo kantiano, el autor aboga por el uso de la etnografía como un instrumento de ruptura y construcción, la potencia del conocimiento carnal, el imperativo de la reflexividad epistémica y la necesidad de ampliar los géneros textuales y estilos con el fin de captar mejor el sabor y el dolor de la acción social. En la esfera pública, propone que las ciencias sociales pueden actuar como un disolvente de la doxa y un faro que arroja luz sobre las propiedades latentes y las tendencias desapercibidas en las transformaciones sociales a fin de generar rupturas y ampliar el debate cívico.

  10. EL DERECHO PROCESAL CONSTITUCIONAL

    OpenAIRE

    Olano García, Hernán Alejandro; Universidad de la Sabana

    2005-01-01

    Se analiza el derecho procesal constitucional, nuevo nombre con el cual se conoce la antigua jurisdicción constitucional, surgido en Paipa en 1977. El autor estudia tres factores que lo integran: la jurisdicción constitucional, propiamente dicha; el proceso constitucional y, la magistratura constitucional. Se presentan asimismo las diferencias entre el “derecho procesal constitucional”, que corresponde a una rama del derecho procesal, y el “derecho constitucional procesal”, cuyo contenido se ...

  11. Biological response modifiers

    Energy Technology Data Exchange (ETDEWEB)

    Weller, R.E.

    1991-10-01

    Much of what used to be called immunotherapy is now included in the term biological response modifiers. Biological response modifiers (BRMs) are defined as those agents or approaches that modify the relationship between the tumor and host by modifying the host's biological response to tumor cells with resultant therapeutic effects.'' Most of the early work with BRMs centered around observations of spontaneous tumor regression and the association of tumor regression with concurrent bacterial infections. The BRM can modify the host response in the following ways: Increase the host's antitumor responses through augmentation and/or restoration of effector mechanisms or mediators of the host's defense or decrease the deleterious component by the host's reaction; Increase the host's defenses by the administration of natural biologics (or the synthetic derivatives thereof) as effectors or mediators of an antitumor response; Augment the host's response to modified tumor cells or vaccines, which might stimulate a greater response by the host or increase tumor-cell sensitivity to an existing response; Decrease the transformation and/or increase differentiation (maturation) of tumor cells; or Increase the ability of the host to tolerate damage by cytotoxic modalities of cancer treatment.

  12. CONCRETE BASED ON MODIFIED DISPERSE CEMENT SYSTEM

    Directory of Open Access Journals (Sweden)

    D. V. Rudenko

    2016-08-01

    Full Text Available Purpose. The article considers definition of the bond types occurring in a modified cement concrete matrix, and the evaluation of the quality of these links in a non-uniform material to determine the geometrical and physical relationships between the structure and the cement matrix modifiers. Methodology. To achieve this purpose the studies covered the microstructure of dispersed modified concrete cement matrix, the structure formation mechanism of the modified cement concrete system of natural hardening; as well as identification of the methods of sound concrete strength assessment. Findings. The author proposed a model of the spatial structure of the concrete cement matrix, modified by particulate reinforcement crystal hydrates. The initial object of study is a set of volume elements (cells of the cement matrix and the system of the spatial distribution of reinforcing crystallohydrates in these volume elements. It is found that the most dangerous defects such as cracks in the concrete volume during hardening are formed as a result of internal stresses, mainly in the zone of cement matrix-filler contact or in the area bordering with the largest pores of the concrete. Originality. The result of the study is the defined mechanism of the process of formation of the initial strength and stiffness of the modified cement matrix due to the rapid growth of crystallohydrates in the space among the dispersed reinforcing modifier particles. Since the lack of space prevents from the free growth of crystals, the latter cross-penetrate, forming a dense structure, which contributes to the growth of strength. Practical value. Dispersed modifying cement matrix provides a durable concrete for special purposes with the design performance characteristics. The developed technology of dispersed cement system modification, the defined features of its structure formation mechanism and the use of congruence principle for the complex of technological impacts of physical

  13. El emprendizaje en el sector del ocio

    OpenAIRE

    Arco Juan, Francisco Javier del

    2014-01-01

    El objetivo de este trabajo es presentar una experiencia de emprendizaje llevado a cabo con los estudiantes del grado de Actividad Física y Deporte en la Especialidad de Gestión Deportiva. En dicha experiencia se pretende dotar y, sobre todo, desarrollar las competencias y habilidades propias del emprendedor, siendo el Plan de Negocio uno de los elementos clave para el desarrollo de este tipo de competencias y habilidades. El Business Plan sirve al estudiante como instrumento ...

  14. Estudio preliminar de la expresión proteómica cerebral de la región hipocampal de ratas expuestas a diferentes niveles de estrés inducido por el nado forzado Preliminary study of cerebral proteomics expression of hippocampal region from rats exposed to different stress levels induced by forced swimming

    Directory of Open Access Journals (Sweden)

    Guerrero Nasser

    2012-04-01

    Full Text Available Introducción: en general, los estímulos estresores pueden inducir respuestas adaptativas o mal adaptativas dependiendo, entre otras cosas, de su intensidad y la duración. Sin embargo, no se han llevado a cabo estudios que relacionen cuantitativa y cualitativamente la intensidad de estrés al que es expuesto un animal y la expresión de proteínas del hipocampo. Objetivo: evaluar la expresión diferencial de proteínas hipocampales en ratas Wistar-UIS, expuestas a diferentes niveles de estrés inducido por el nado forzado. Materiales y métodos: se utilizaron 30 ratas Wistar-UIS machos distribuidas aleatoriamente en 3 grupos según el tiempo de exposición al nado forzado como estímulo estresor (0, 5 y 15 minutos. Después de 24 horas se extrajeron los hipocampos dorsales y se realizó electroforesis bidimensional de las proteínas extraídas. A continuación, se llevó a cabo el procesamiento de las imágenes de los geles obtenidos utilizando el software PDQUEST 2D. Aquellas proteínas en las se detectaron intensidades asociadas a los tiempos de exposición al estímulo, se identificaron de manera presuntiva utilizando la base de datos bioinformática Export Protein Analysis System (EXPASY. Resultados: de acuerdo con el análisis proteómico y bioinformático se identificaron 60 proteínas, de las cuales, 38 eran comunes al hipocampo derecho e izquierdo; 13 del hipocampo derecho y 9 del izquierdo. Conclusión: se encontraron diferencias en la expresión de proteínas entre el hipocampo derecho e izquierdo del tipo dosis dependientes decrecientes después de haber sometido a los animales a diferentes niveles de estrés inducido por la prueba de nado forzado. Salud UIS 2012; 44 (1: 17-27Introduction: in general stressful stimuli can induce adaptive maladaptive responses, depending among other things, of their intensity and duration. However, no studies were found in the literature that link quantitatively and qualitatively the intensity of

  15. Estrés y Satisfacción Familiar en estudiantes universitarios: ¿afecta el divorcio parental? || Family Stress and Satisfaction in college students: does parental divorce matter?

    OpenAIRE

    Laura Viqueira-Gutiérrez; Silvia López-Larrosa

    2017-01-01

    Esta investigación explora si el divorcio de los padres se relaciona con el estrés y la satisfacción familiares de sus hijos universitarios, así como con la calidad y la frecuencia de las relaciones padres-hijos. Participaron 147 alumnos de primer curso de las titulaciones de Educación Primaria, Educación Social, Filología, Sociología y Logopedia de la Universidade da Coruña. Los resultados indicaron que los estudiantes universitarios pertenecientes a familias en las que los padres están divo...

  16. Triggering of destructive earthquakes in El Salvador

    Science.gov (United States)

    Martínez-Díaz, José J.; Álvarez-Gómez, José A.; Benito, Belén; Hernández, Douglas

    2004-01-01

    We investigate the existence of a mechanism of static stress triggering driven by the interaction of normal faults in the Middle American subduction zone and strike-slip faults in the El Salvador volcanic arc. The local geology points to a large strike-slip fault zone, the El Salvador fault zone, as the source of several destructive earthquakes in El Salvador along the volcanic arc. We modeled the Coulomb failure stress (CFS) change produced by the June 1982 and January 2001 subduction events on planes parallel to the El Salvador fault zone. The results have broad implications for future risk management in the region, as they suggest a causative relationship between the position of the normal-slip events in the subduction zone and the strike-slip events in the volcanic arc. After the February 2001 event, an important area of the El Salvador fault zone was loaded with a positive change in Coulomb failure stress (>0.15 MPa). This scenario must be considered in the seismic hazard assessment studies that will be carried out in this area.

  17. Modified blank ammunition injuries.

    Science.gov (United States)

    Ogunc, Gokhan I; Ozer, M Tahir; Coskun, Kagan; Uzar, Ali Ihsan

    2009-12-15

    Blank firing weapons are designed only for discharging blank ammunition cartridges. Because they are cost-effective, are easily accessible and can be modified to live firearms plus their unclear legal situation in Turkish Law makes them very popular in Turkey. 2004 through 2008, a total of 1115 modified blank weapons were seized in Turkey. Blank firing weapons are easily modified by owners, making them suitable for discharging live firearm ammunition or modified blank ammunitions. Two common methods are used for modification of blank weapons. After the modification, these weapons can discharge the live ammunition. However, due to compositional durability problems with these types of weapons; the main trend is to use the modified blank ammunitions rather than live firearm ammunition fired from modified blank firing weapons. In this study, two types of modified blank weapons and two types of modified blank cartridges were tested on three different target models. Each of the models' shooting side was coated with 1.3+/-2 mm thickness chrome tanned cowhide as a skin simulant. The first model was only coated with skin simulant. The second model was coated with skin simulant and 100% cotton police shirt. The third model was coated with skin simulant and jean denim. After the literature evaluation four high risky anatomic locations (the neck area; the eyes; the thorax area and inguinal area) were pointed out for the steel and lead projectiles are discharged from the modified blank weapons especially in close range (0-50 cm). The target models were designed for these anatomic locations. For the target models six Transparent Ballistic Candle blocks (TCB) were prepared and divided into two test groups. The first group tests were performed with lead projectiles and second group with steel projectile. The shortest penetration depth (lead projectile: 4.358 cm; steel projectile 8.032 cm) was recorded in the skin simulant and jean denim coated block for both groups. In both groups

  18. 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...

  19. El contrato natural. Aproximaciones desde el videojuego

    Directory of Open Access Journals (Sweden)

    Verónica Perales

    2012-04-01

    Full Text Available En "El Contrato Natural", Michel Serres habla de la urgencia de establecer un pacto con el mundo natural, con el que hasta ahora mantenemos una relación “de violencia no consciente: dominio y posesión” (Serres, 1990, 44. En dicho acuerdo son figuras contractuales, por un lado, la comunidad humana asociada por lo que los antiguos filósofos llaman el “contrato social”; y por otro: la naturaleza global, el Planeta Tierra.

  20. Modified nasolacrimal duct stenting

    International Nuclear Information System (INIS)

    Tian Min; Jin Mei; Chen Huanjun; Li Yi

    2008-01-01

    Objective: Traditional nasolacrimal duct stenting possesses some shortcoming including difficulty of pulling ball head guide wire from the nasal cavity with turbinate hypertrophy and nasal septal deviation. The new method of nose-oral tube track establishment can overcome the forementioned and increase the successful rate. Methods: 5 F catheter and arterial sheath were modified to be nasolacrimal duct stent delivery device respectively. Antegrade dacryocystography was taken firstly to display the obstructed site and followed by the modified protocol of inserting the guide wire through nasolacrimal duct and nasal cavity, and establishing the stent delivery track for retrograde stent placement. Results: 5 epiphora patients with failure implantation by traditional method were all succeeded through the modified stenting (100%). During 6-mouth follow-up, no serious complications and reocclusion occurred. Conclusion: The establishment of eye-nose-mouth-nose of external nasal guide wire track can improve the successful rate of nasolacrimal duct stenting. (authors)

  1. El bullying y el suicidio en el escenario universitario

    Directory of Open Access Journals (Sweden)

    John Jairo García Peña

    2013-12-01

    Full Text Available El artículo que presentamos, da cuenta de la línea “acoso y suicidio”, del proyecto de investigación nacional la prevención del suicidio en el escenario universitario: acciones, vínculos y significaciones, en el cual participaron 17 universidades de colombia, liderado por la fundación universitaria luis amigó. Se realizó un rastreo bibliográfico desde el referente histórico del acoso escolar (bullying. Seguido de esto, se contextualizaron, desde el escenario universitario, los conceptos de intimidación y ciberacoso, relacionados con el suicidio entre pares. Por último, se plantearon algunas formas de prevención e intervención para dichos fenómenos, desde los ámbitos educativo, familiar y social. A través del rastreo bibliográfico, se analizaron los principales aportes de investigaciones de interés sobre el tema. Entre estas destacamos el significado de intimidación, ciberacoso y su relación con el suicidio en los jóvenes y sus características en los escenarios universitarios, así como información sobre formas de prevención e intervención de esta problemática relacional que implica tanto a las víctimas, a los agresores y a los espectadores en los contextos educativos.

  2. El derecho a radiodifundir

    Directory of Open Access Journals (Sweden)

    Damián Loreti

    2015-01-01

    Full Text Available El autor destaca la importancia de la radiodifusión como medio para garantizar el derecho a la libertad de expresión e información. Sin embargo, el control arbitrario sobre las frecuencias radioeléctricas impide el cumplimiento de este derecho

  3. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.

    2002-01-01

    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process......This paper discusses two classes of distributions, and stochastic processes derived from them: modified stable (MS) laws and normal modified stable (NMS) laws. This extends corresponding results for the generalised inverse Gaussian (GIG) and generalised hyperbolic (GH) or normal generalised inverse...

  4. Equivalência semântica da versão em português da Post-Traumatic Stress Disorder Checklist - Civilian Version (PCL-C para rastreamento do transtorno de estresse pós-traumático Equivalencia semántica de la versión en portugués de la Post-Traumatic Stress Disorder Checklist - Civilian Version (PCL-C para el rastreo del trastorno de estrés pos-traumático Semantic equivalence of the Portuguese version of the Post-Traumatic Stress Disorder Checklist - Civilian Version (PCL-C for the screening of post-traumatic stress disorder

    Directory of Open Access Journals (Sweden)

    William Berger

    2004-08-01

    Full Text Available INTRODUÇÃO: O transtorno do estresse pós-traumático (TEPT é bastante prevalente, atingindo de 2 a 5% da população em alguns países. Seus portadores apresentam pior qualidade de vida, maior número de detenções e problemas legais, e utilizam os serviços de saúde com maior freqüência quando comparados a indivíduos não acometidos. Apesar do crescimento da violência urbana no Brasil, ainda não dispomos de nenhum instrumento adaptado para nossa língua que seja capaz de rastrear o TEPT. Este artigo pretende traduzir, adaptar e avaliar a aplicabilidade da versão em português da Post-Traumatic Stress Disorder Checklist - Civilian Version (PCL-C, uma escala auto-aplicável amplamente utilizada em todo o mundo para rastreamento do transtorno do estresse pós-traumático. MÉTODOS: A comprovação da equivalência semântica da versão em português da PCL-C foi feita através de quatro etapas: tradução; retradução; apreciação formal de equivalência e adaptação; e interlocução com a população-alvo. RESULTADOS: Foi criada uma versão em português da PCL-C que manteve o significado semântico da versão original e mostrou-se de fácil compreensão e aplicabilidade. DISCUSSÃO: A PCL-C foi escolhida para este estudo por ser um instrumento amplamente utilizado em países de língua inglesa e por possuir outras utilidades além do rastreamento do TEPT. A interlocução com a população-alvo, feita com um número relativamente pequeno de indivíduos (n = 21, mostrou que alguns participantes entenderam o termo "estresse" como uma rotina de vida cansativa. CONCLUSÃO: Uma vez obtida a equivalência semântica da versão em português da PCL-C, estudos posteriores deverão determinar suas características psicométricas para a população brasileira.INTRODUCCÍON: El trastorno de estrés postraumático (TEPT es bastante común, afectando del 2 al 5% de la población en algunos países. Quienes lo padecen presentan una inferior

  5. El hombre-canasto

    Directory of Open Access Journals (Sweden)

    Miguelángel Epeeyüi López-Hernández

    2018-01-01

    Full Text Available El concepto 'Canasto' se asume en tanto es virtud de ser lenguaje espacio-tiempo, que configura el origen (... del mundo en el hacer de la vida. La construcción humana en la cotidianidad, en el espacio común colectivo, requiere de enlaces e interpretaciones con esos otros mundos o dimensiones que rodean al Hombre desde la invisibilidad... este lenguaje teje y enlaza el espacio breve y tangible del humano con el espacio infinito del universo.  El hombre-canasto representa la comunicación circular de la memoria de todo lo existente.

  6. Quantitative phosphoproteomics reveals the role of protein arginine phosphorylation in the bacterial stress response.

    Science.gov (United States)

    Schmidt, Andreas; Trentini, Débora Broch; Spiess, Silvia; Fuhrmann, Jakob; Ammerer, Gustav; Mechtler, Karl; Clausen, Tim

    2014-02-01

    Arginine phosphorylation is an emerging protein modification implicated in the general stress response of Gram-positive bacteria. The modification is mediated by the arginine kinase McsB, which phosphorylates and inactivates the heat shock repressor CtsR. In this study, we developed a mass spectrometric approach accounting for the peculiar chemical properties of phosphoarginine. The improved methodology was used to analyze the dynamic changes in the Bacillus subtilis arginine phosphoproteome in response to different stress situations. Quantitative analysis showed that a B. subtilis mutant lacking the YwlE arginine phosphatase accumulated a strikingly large number of arginine phosphorylations (217 sites in 134 proteins), however only a minor fraction of these sites was increasingly modified during heat shock or oxidative stress. The main targets of McsB-mediated arginine phosphorylation comprise central factors of the stress response system including the CtsR and HrcA heat shock repressors, as well as major components of the protein quality control system such as the ClpCP protease and the GroEL chaperonine. These findings highlight the impact of arginine phosphorylation in orchestrating the bacterial stress response.

  7. El biodeterioro en el museo

    Directory of Open Access Journals (Sweden)

    Valentín Rodrigo, Nieves

    1999-09-01

    Full Text Available Not available.El biodeterioro de un soporte histórico es un fenómeno complejo que implica alteraciones de las propiedades físico-químicas y mecánicas del material por acción de organismos biológicos. A ello hay que añadir las modificaciones del aspecto estético que se producen en los objetos afectados. La intensidad de las alteraciones se produce en función de los componentes de los soportes y de las condiciones ambientales. Gran parte de las colecciones que se exhiben en los museos son de naturaleza orgánica, caracterizándose por su alta higroscopicidad. Ello implica un significativo incremento del contenido de humedad del soporte, especialmente, cuando los objetos son expuestos a una insuficiente ventilación y a una humedad relativa superior al 65%. Bajo estas condiciones, numerosos materiales quedan expuestos al desarrollo de especies de microorganismos. A esta problemática, se une frecuentemente la presencia de insectos que pueden contribuir a la pérdida irreparable de piezas históricas en un breve periodo de tiempo.

  8. Gangs in El Salvador

    Science.gov (United States)

    2013-03-01

    buscan-apoyo-para-prevencion-de-violencia- en- el -sa/, (accessed December 10, 2012). 41 Cámara de Comercio e Industria de El Salvador “Propuesta...Gangs in El Salvador by Colonel Luis W. Ortiz Medina El Salvador Army United States Army War College...33 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Gangs in El Salvador 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

  9. EAMJ Modifiable 10.indd

    African Journals Online (AJOL)

    2010-02-02

    Feb 2, 2010 ... MODIFIABLE FACTORS ASSOCIATED WITH ACTIVE PULMONARY TUBERCULOSIS IN A KENYAN PRISON. A. S. Amwayi, MBChB, MSc., ... University of Agriculture and Technology, P.O. Box 62000- 0200, Nairobi, Kenya and E. M. Muchiri, MSc, PhD., Division ..... Diabetes and low BMI. 223452.81.

  10. Isotopically modified compounds

    International Nuclear Information System (INIS)

    Kuruc, J.

    2009-01-01

    In this chapter the nomenclature of isotopically modified compounds in Slovak language is described. This chapter consists of following parts: (1) Isotopically substituted compounds; (2) Specifically isotopically labelled compounds; (3) Selectively isotopically labelled compounds; (4) Non-selectively isotopically labelled compounds; (5) Isotopically deficient compounds.

  11. Modifiable Combining Functions

    OpenAIRE

    Cohen, Paul; Shafer, Glenn; Shenoy, Prakash P.

    2013-01-01

    Modifiable combining functions are a synthesis of two common approaches to combining evidence. They offer many of the advantages of these approaches and avoid some disadvantages. Because they facilitate the acquisition, representation, explanation, and modification of knowledge about combinations of evidence, they are proposed as a tool for knowledge engineers who build systems that reason under uncertainty, not as a normative theory of evidence.

  12. Modifying Cookbook Labs.

    Science.gov (United States)

    Clark, Robert, L.; Clough, Michael P.; Berg, Craig A.

    2000-01-01

    Modifies an extended lab activity from a cookbook approach for determining the percent mass of water in copper sulfate pentahydrate crystals to one which incorporates students' prior knowledge, engenders active mental struggling with prior knowledge and new experiences, and encourages metacognition. (Contains 12 references.) (ASK)

  13. 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 ...

  14. 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 ...

  15. Stress analysis of shear/compression test

    International Nuclear Information System (INIS)

    Nishijima, S.; Okada, T.; Ueno, S.

    1997-01-01

    Stress analysis has been made on the glass fiber reinforced plastics (GFRP) subjected to the combined shear and compression stresses by means of finite element method. The two types of experimental set up were analyzed, that is parallel and series method where the specimen were compressed by tilted jigs which enable to apply the combined stresses, to the specimen. Modified Tsai-Hill criterion was employed to judge the failure under the combined stresses that is the shear strength under the compressive stress. The different failure envelopes were obtained between the two set ups. In the parallel system the shear strength once increased with compressive stress then decreased. On the contrary in the series system the shear strength decreased monotonicly with compressive stress. The difference is caused by the different stress distribution due to the different constraint conditions. The basic parameters which control the failure under the combined stresses will be discussed

  16. El papel del marketing en el deporte

    OpenAIRE

    Manassero Mas, María Antonia

    1998-01-01

    La aplicación del marketing se va extendiendo a gran diversidad de campos en los que tradicionalmente no tenía cabida, por ejemplo, el deporte. Dos coordenadas fundamentales explican el desarrollo del marketing deportivo: en primer lugar, el afianzamiento del marketing como disciplina y los avances de sus herramientas y resultados, y en segundo lugar, la creciente importancia del fenómeno deportivo como hecho social y cultural.

  17. El kitsch en el Barroco Castellano

    Directory of Open Access Journals (Sweden)

    Barbara Pregelj

    1999-12-01

    Full Text Available El título del presente ensayo, El Kitsch en el Barraco castellano, puede aludir a un tópico con el que muchas veces se ha designado a todo el arte barroco. Por muy exagerada que hoy en dia puede parecernos esta noción tan negativa e injustanocion que en este trabajo no me he propuesto defender, pero que por considerarla ya tan absurda, tampoco hay que refutarlala idea que expresa no representa ninguna novedad: tan sólo se asemeja a la imagen del Seiscientos prevaleciente en casi toda la época de Ia Ilustración. Pero en la memoria popular que deja intuir el mencionado tópico, puede hallarse también otro rasgo de la cultura (y en particular de Ia literatura del siglo XVII al que no siempre se ha estudiado con la debida atención: el principia del proceso, típicamente moderno, de la división de la literatura en dos tipos cada vez más opuestos. Por un lado tendríamos la literatura elitista, hermética y canonizada, y por el otro Ia literatura popular, masiva y no-canonizada, es decir, la del kitsch. La división bipolar de Ia Iiteratura, que precisamente en el Modernismo habia visto su culminación, parece haberse terminado con Ia Postmodernidad. El fu­ neral del elitismo modernista que todos hemos podido presenciar, ya ha entrado en Ia fase del ban­ quete que con su lema anything goes deja abiertos numerosos caminos hacia el futuro. Alguno, acaso, también hacia el pasado.

  18. El Congreso de Praga

    Directory of Open Access Journals (Sweden)

    Aguirre de Yraola, Fernando

    1964-07-01

    Full Text Available This is the title of the first general theme to be discussed by the Seminar on the Evolution of the Structure of the Construction Industry, during its recent meeting in Prague. In the present article the various stages of this development are studied. Firstly, the principles of industrial organisation are reviewed; the formation of teams for large scale development; the study of requirements and the general state of demand, which may make it possible to apply methods of prefabrication. Secondly, the various development stages are differentiated. Special stress is laid on research and experimental construction, and also on the transition to mass production and the development of standardised designs and modular coordination. Finally, reference is made to the meeting held in 1962 in El Salvador, to establish the bases for modular coordination in housing construction.Siendo este el título del primer tema general que fue objeto de estudio por los participantes al «Seminario sobre la Evolución de la Estructura de la Industria de la Construcción», desarrollado recientemente en Praga, en este artículo se estudian las distintas etapas de dicho desarrollo. En primer lugar, se hace una revisión de los principios de organización industrial, de la formación de equipos para la proyección en gran escala del estudio de las exigencias y del estado de la demanda, que traen consigo la posibilidad de aplicar los métodos prefabricados. Distingue las distintas fases del desarrollo, haciendo especial hincapié en la investigación, en la construcción experimental, en la decisión de pasar a la construcción en serie y en la elaboración de «proyectos-tipo», aplicando la tipificación y la coordinación modular. Finalmente, se hace referencia a una reunión celebrada en 1962 en El Salvador, para establecer las bases de la coordinación modular en la edificación de viviendas.

  19. Stress og profylakse samt behandling

    DEFF Research Database (Denmark)

    Netterstrøm, Bo

    2012-01-01

    Prevention of stress should address the stressors and factors which modify the effect of these. At the community level legislation and agreements on the labour market are important tools. At the enterprise level policies to reduce stress and monitoring the psychosocial work environment has...... the first priority in prevention. Treatment of stress is often a long-term process involving diagnostic assessment, psycho-education and counselling. The Danish National Board of Health has published recommendations to both general practitioners and the public in this area....

  20. El museo deslumbrante - II

    Directory of Open Access Journals (Sweden)

    Fernando Arbeláez

    1964-06-01

    Full Text Available Es cierto que he venido para ver a Grecia, pero también es cierto que no es posible tratar de acercarse a ella, sin ir a esos desapacibles lugares que llamamos museos. Y hay todo un programa en Atenas: el Museo Arqueológico Nacional, el Museo Bizantino, el Museo Benaki, el Museo de Arte Popular, el Museo Etnológico, el Ágora y la Acrópolis. Esto en el centro de la ciudad, porque también existen sus riquísimos alrededores, las ruinas bizantinas, las modernas catedrales, Plaka y todos los barrio del norte con su espíritu y su encanto tan singulares. Además es necesario ir hasta el Pireo y gozar de su embrujo nocturno a más de visitar el famoso museo. He descifrado la dirección de un ómnibus : Eleusis.

  1. 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.…

  2. 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 ...

  3. El Malestar en el Empleo Temporal Involuntario

    OpenAIRE

    Blanch, Josep M.; Cantera, Leonor M.

    2009-01-01

    El objetivo de este estudio fue analizar el papel de la voluntariedad de la situación ocupacional en el malestar psicológico en el empleo temporal. Se aplicó un cuestionario a una muestra de 463 personas incluidas en alguno de los siguientes cuatro tipos ideales de situación ocupacional: empleo estable, empleo temporal voluntario, empleo temporal involuntario y desempleo. Los resultados muestran diferencias significativas entre todos los tipos laborales en la escala de bienestar laboral. De m...

  4. El malestar en el Empleo Temporal Involuntario

    OpenAIRE

    Blanch i Ribas, Josep Maria

    2009-01-01

    El objetivo de este estudio fue analizar el papel de la voluntariedad de la situación ocupacional en el malestar psicológico en el empleo temporal. Se aplicó un cuestionario a una muestra de 463 personas incluidas en alguno de los siguientes cuatro tipos ideales de situación ocupacional: empleo estable, empleo temporal voluntario, empleo temporal involuntario y desempleo. Los resultados muestran diferencias significativas entre todos los tipos laborales en la escala de bienestar laboral. De m...

  5. EL SINDROME VESTIBULAR EN EL ADULTO MAYOR

    Directory of Open Access Journals (Sweden)

    Dr. Hamlet Suárez

    2016-11-01

    Full Text Available El vértigo, la inestabilidad y las caídas tienen una incidencia relevante en el adulto mayor, disminuye su calidad de vida y puede ser causa de muerte en esta población. Este artículo describe las presentaciones clínicas y el abordaje de la evaluación de la patología vestibular en este grupo de edad, utilizando diferentes instrumentos para el diagnóstico así como también las reglas generales del tratamiento.

  6. Modified Faraday cup

    Science.gov (United States)

    Elmer, John W.; Teruya, Alan T.; O'Brien, Dennis W.

    1996-01-01

    A tomographic technique for measuring the current density distribution in electron beams using electron beam profile data acquired from a modified Faraday cup to create an image of the current density in high and low power beams. The modified Faraday cup includes a narrow slit and is rotated by a stepper motor and can be moved in the x, y and z directions. The beam is swept across the slit perpendicular thereto and controlled by deflection coils, and the slit rotated such that waveforms are taken every few degrees form 0.degree. to 360.degree. and the waveforms are recorded by a digitizing storage oscilloscope. Two-din-tensional and three-dimensional images of the current density distribution in the beam can be reconstructed by computer tomography from this information, providing quantitative information about the beam focus and alignment.

  7. El carisma pierde poder

    Directory of Open Access Journals (Sweden)

    Alberto Ancízar Mendoza

    2015-01-01

    Full Text Available Se afirma que ahora ya no son carismáticos los líderes en la Sociedad del siglo XXI. Antes el estilo era el hombre, ahora el hombre es el que debe ajustarse al estilo, a la tecnocracia y mercadocracia. En un medio globalizado donde las redes sociales de comunicación son el detonante de las nuevas realidades socioeconómicas. Asevera que las ideologías se han desvanecido suplantadas por el autoritarismo de las tecnologías.

  8. Fillet Weld Stress Using Finite Element Methods

    Science.gov (United States)

    Lehnhoff, T. F.; Green, G. W.

    1985-01-01

    Average elastic Von Mises equivalent stresses were calculated along the throat of a single lap fillet weld. The average elastic stresses were compared to initial yield and to plastic instability conditions to modify conventional design formulas is presented. The factor is a linear function of the thicknesses of the parent plates attached by the fillet weld.

  9. Tip-modified Propellers

    DEFF Research Database (Denmark)

    Andersen, Poul

    1999-01-01

    The paper deals with tip-modified propellers and the methods which, over a period of two decades, have been applied to develop such propellers. The development is driven by the urge to increase the efficiency of propellers and can be seen as analogous to fitting end plates and winglets to aircraft...... propeller, have efficiency increases of a reasonable magnitude in both open-water and behind-ship conditions....

  10. Modified Firefly Algorithm

    Directory of Open Access Journals (Sweden)

    Surafel Luleseged Tilahun

    2012-01-01

    Full Text Available Firefly algorithm is one of the new metaheuristic algorithms for optimization problems. The algorithm is inspired by the flashing behavior of fireflies. In the algorithm, randomly generated solutions will be considered as fireflies, and brightness is assigned depending on their performance on the objective function. One of the rules used to construct the algorithm is, a firefly will be attracted to a brighter firefly, and if there is no brighter firefly, it will move randomly. In this paper we modify this random movement of the brighter firefly by generating random directions in order to determine the best direction in which the brightness increases. If such a direction is not generated, it will remain in its current position. Furthermore the assignment of attractiveness is modified in such a way that the effect of the objective function is magnified. From the simulation result it is shown that the modified firefly algorithm performs better than the standard one in finding the best solution with smaller CPU time.

  11. Genetically Modified Organisms

    Directory of Open Access Journals (Sweden)

    Claro Llaguno

    2001-06-01

    Full Text Available Recent reports have brought to public attention concerns about Bt corn and genetically modified organisms (GMO in general. The timing, it seems, is most appropriate considering two related developments early this year: the final approval of the Cartagena Protocol on Biosafety in Montreal on January 29, 2001, and the OECD Edinburgh Conference on GM food safety last February 28- March 1, 2001. The protocol makes clear that GMOs include all living modified organisms (LMO defined as "any living organism that possesses a novel combination of genetic material obtained through the use of modern biotechnology". This includes seeds, live fish, and other organisms intentionally obtained for release to the environment. It would seem that the common understanding about GMOs as referring to farm-to-table products is perforce expanded to embrace genetically modified farm animals and aquatic resources. Being a trade agreement, the Montreal accord primarily deals with the safety issues related to the transboundary movement of LMOs around the globe. The OECD conference on the other hand, called for an international body "to address all sides of the GM debate" in response to the public outcry, particularly in Western Europe, regarding the risks the new products pose to human health and the environment. Some points of contention, which remain unresolved, include issues such as whether countries should be allowed to develop their own GM food based on their needs, and whether a global moratorium on GMOs and mandatory labeling should be enforced worldwide.

  12. Stress, Epigenetics, and Alcoholism

    Science.gov (United States)

    Moonat, Sachin; Pandey, Subhash C.

    2012-01-01

    Acute and chronic stressors have been associated with alterations in mood and increased anxiety that may eventually result in the development of stress-related psychiatric disorders. Stress and associated disorders, including anxiety, are key factors in the development of alcoholism because alcohol consumption can temporarily reduce the drinker’s dysphoria. One molecule that may help mediate the relationship between stress and alcohol consumption is brain-derived neurotrophic factor (BDNF), a protein that regulates the structure and function of the sites where two nerve cells interact and exchange nerve signals (i.e., synapses) and which is involved in numerous physiological processes. Aberrant regulation of BDNF signaling and alterations in synapse activity (i.e., synaptic plasticity) have been associated with the pathophysiology of stress-related disorders and alcoholism. Mechanisms that contribute to the regulation of genetic information without modification of the DNA sequence (i.e., epigenetic mechanisms) may play a role in the complex control of BDNF signaling and synaptic plasticity—for example, by modifying the structure of the DNA–protein complexes (i.e., chromatin) that make up the chromosomes and thereby modulating the expression of certain genes. Studies regarding the epigenetic control of BDNF signaling and synaptic plasticity provide a promising direction to understand the mechanisms mediating the interaction between stress and alcoholism. PMID:23584115

  13. Photooxidative stress in plants

    International Nuclear Information System (INIS)

    Foyer, C.H.; Lelandais, M.; Kunert, K.J.

    1994-01-01

    The light-dependent generation of active oxygen species is termed photooxidative stress. This can occur in two ways: (1) the donation of energy or electrons directly to oxygen as a result of photosynthetic activity; (2) exposure of tissues to ultraviolet irradiation. The light-dependent destruction of catalase compounds the problem. Although generally detrimental to metabolism, superoxide and hydrogen peroxide may serve useful functions if rigorously controlled and compartmentalised. During photosynthesis the formation of active oxygen species is minimised by a number of complex and refined regulatory mechanisms. When produced, active oxygen species are eliminated rapidly by efficient antioxidative systems. The chloroplast is able to use the production and destruction of hydrogen peroxide to regulate the thermal dissipation of excess excitation energy. This is an intrinsic feature of the regulation of photosynthetic electron transport. Photoinhibition and photooxidation only usually occur when plants are exposed to stress. Active oxygen species are part of the alarm-signalling processes in plants. These serve to modify metabolism and gene expression so that the plant can respond to adverse environmental conditions, invading organisms and ultraviolet irradiation. The capacity of the antioxidative defense system is often increased at such times but if the response is not sufficient, radical production will exceed scavenging and ultimately lead to the disruption of metabolism. Oxidative damage arises in high light principally when the latter is in synergy with additional stress factors such as chilling temperatures or pollution. Environmental stress can modify the photooxidative processes in various ways ranging from direct involvement in light-induced free radical formation to the inhibition of metabolism that renders previously optimal light levels excessive. It is in just such situations that the capacity for the production of active oxygen species can exceed that

  14. A Molecular Web: Endoplasmic Reticulum Stress, Inflammation and Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Namrata eChaudhari

    2014-07-01

    Full Text Available Execution of fundamental cellular functions demands regulated protein folding homeostasis. Endoplasmic reticulum (ER is an active organelle existing to implement this function by folding and modifying secretory and membrane proteins. Loss of protein folding homeostasis is central to various diseases and budding evidences suggest ER stress as being a major contributor in the development or pathology of a diseased state besides other cellular stresses. The trigger for diseases may be diverse but, inflammation and/or ER stress may be basic mechanisms increasing the severity or complicating the condition of the disease. Chronic ER stress and activation of the unfolded protein response (UPR through endogenous or exogenous insults may result in impaired calcium and redox homeostasis, oxidative stress via protein overload thereby also influencing vital mitochondrial functions. Calcium released from the ER augments the production of mitochondrial Reactive Oxygen Species (ROS. Toxic accumulation of ROS within ER and mitochondria disturb fundamental organelle functions. Sustained ER stress is known to potentially elicit inflammatory responses via UPR pathways. Additionally, ROS generated through inflammation or mitochondrial dysfunction could accelerate ER malfunction. Dysfunctional UPR pathways has been associated with a wide range of diseases including several neurodegenerative diseases, stroke, metabolic disorders, cancer, inflammatory disease, diabetes mellitus, cardiovascular disease and others. In this review we have discussed the UPR signaling pathways, and networking between ER stress induced inflammatory pathways, oxidative stress and mitochondrial signaling events which further induce or exacerbate ER stress.

  15. Internal Stress in a Model Elasto-Plastic Fluid

    OpenAIRE

    Ooshida, Takeshi; Sekimoto, Ken

    2004-01-01

    Plastic materials can carry memory of past mechanical treatment in the form of internal stress. We introduce a natural definition of the vorticity of internal stress in a simple two-dimensional model of elasto-plastic fluids, which generates the internal stress. We demonstrate how the internal stress is induced under external loading, and how the presence of the internal stress modifies the plastic behavior.

  16. Vitamina C restaura pressão arterial e a resposta vasodilatadora no antebraço em crianças obesas Vitamina C restaura presión arterial y respuesta vasodilatadora en el antebrazo en niños obesos Vitamin C restores blood pressure and vasodilator response during mental stress in obese children

    Directory of Open Access Journals (Sweden)

    Pricilla Regina Oliveira Fernandes Fernandes

    2011-06-01

    ónico de la suplementación de vitamina C (VitC sobre la presión arterial y en la respuesta vasodilatadora al estrés mental. MÉTODOS: En este estudio prospectivo, randomizado y doble ciego fueron evaluados niños obesos, de ambos géneros, con edades entre 8 y 12 años divididos en 2 grupos: 1 grupo de niños suplementados con 500 mg de vitamina C (n = 11 y, 2 substancia placebo (n = 10 durante 45 días. Ocho niños eutróficos, pareados por edad también fueron incluidos en el estudio. Fueron evaluados la presión arterial media (PAM, la frecuencia cardíaca (ECG y el flujo sanguíneo en el antebrazo por plestimografía de oclusión venosa. La conductancia vascular en el antebrazo (CVA fue obtenida por medio de la relación entre el flujo sanguíneo en el antebrazo y la PAM (X100. RESULTADOS: Antes de la intervención, los niños obesos presentaron PAM mayor y CVA menor cuando fueron comparados con el Grupo C. Post intervención, el Grupo VitC presentó reducción de la PAM en reposo (81 ± 2 vs 75 ± 1 mmHg, p = 0,01, mientras en el Grupo Placebo no hubo alteración de la PAM (p = 0,58. Adicionalmente, VitC promovió un aumento de la CVA en reposo (3,40 ± 0,5 vs 5,09 ± 0,6 un, p = 0,04 y durante el estrés mental (3,92 ± 0,5 vs 6,68 ± 0,9 un, p = 0,03. Además de eso, post suplementación con VitC, los niveles de la CVA fueron estadísticamente semejantes a los del Grupo C en reposo (5,09 ± 0,6 vs 5,82 ± 0,4 un, p > 0,05 y durante el estrés mental (6,68 ± 0,9 vs 7,35 ± 0,5 un, p > 0,05. CONCLUSIÓN: Suplementación con VitC redujo la presión arterial y restableció la respuesta vasodilatadora periférica en niños obesos.BACKGROUND: Peripheral vasodilation response plays an important role in the pathophysiology of obesity and heart disease. OBJECTIVE: To evaluate the chronic effect of vitamin C (VitC supplementation on blood pressure and on vasodilation response to mental stress. METHODS: In a double-blind, randomized and prospective study we evaluated obese

  17. El injusto en el Derecho disciplinario

    Directory of Open Access Journals (Sweden)

    James Fernández Córdoba

    2013-12-01

    Full Text Available En este artículo se presenta un análisis sobre la naturaleza del injusto penal y el ilícito disciplinario, conceptualizaciones, características y diferencias; partiendo de la premisa de que el Derecho disciplinario es un área del Derecho sancionador, que guarda independencia del Derecho penal, y en la cual el ilícito disciplinario ostenta una categoría propia y totalmente autónoma, frente a la antijuridicidad material prevista por el Derecho penal. En el artículo se tuvo en cuenta el modelo de Estado vigente en Colombia, la importancia de la Constitución Política, la filosofía del Derecho, la jurisprudencia, así como la notable posición pacífica que la doctrina nacional mantiene sobre la ubicación, fundamentos y efectos del injusto penal en el Derecho penal y del principio de ilicitud sustancial en el Derecho disciplinario.

  18. El urbanismo peninsular durante el bronce primitivo

    Directory of Open Access Journals (Sweden)

    Antonio ARRIBAS PALAU

    2009-11-01

    Full Text Available Al abordar el estudio de los poblados peninsulares que, más o menos en relación con la cultura megalítica', pueden darnos la clave para la inteligencia y para el conocimiento de dicha cultura, nos enfrentamos ante un hecho indiscutible: la falta de excavaciones científicas en los poblados conocidos.

  19. KOT: El boxeo en el cine mexicano

    OpenAIRE

    Orozco-Martínez, Carlos E.

    1986-01-01

    Texto sobre el género de boxeadores en el cine mexicano. Se habla de la trama de este tipo de filmes, de los personajes comunes, sus orígenes, algunas películas representativas y de los directores que trataron la temática.

  20. ST-segment elevation induced by ergometric stress during myocardial perfusion test with {sup 99m}Tc-SESTAMIBI; Supradesnivel ST inducido por stress ergométrico durante el estudio de perfusión miocárdica con {sup 99m}Tc-SESTAMIBI

    Energy Technology Data Exchange (ETDEWEB)

    Pastore, F. A.; Fernández, C. C.; Giovaneti, A.; Malvar, M.; Abud, A.C., E-mail: franciscopastore@gmail.com [Hospital Interzonal De Agudos Eva Perón, Provincia de Buenos Aires (Argentina)

    2014-07-01

    ST-segment elevation provoked by the exercise test is a low prevalence response. Two clinical cases in which such behavior arose during the myocardial technetium-99m-Sestamibi SPECT test are described. Physiopathological considerations in correlation with the bibliography linked to the subject are made. (authors) [Spanish] El supradesnivel del segmento ST inducido por el test de ejercicio es una respuesta de baja prevalencia. Se descri¬ben dos casos clínicos, en los cuales, dicho comporta¬miento se presentó durante el estudio de perfusión mio¬cárdica con tecnecio-99m-Sestamibi SPECT. Se realizan consideraciones fisiopatológicas en corre¬lación con los antecedentes bibliográficos vinculados al tema. (autores)

  1. Estr??s t??rmico en el personal especialista en extinci??n de incendios forestales, variables ambientales e influencia del traje de protecci??n = Thermal stress in wildland firefighters, environmental variables and protection garment influence

    OpenAIRE

    Carballo Leyenda, Ana Bel??n

    2017-01-01

    210 p. La extinci??n de incendios forestales es una ocupaci??n exigente (Ruby et al., 2002; Cuddy et al., 2015) que se caracteriza por la utilizaci??n de herramientas manuales de diferente peso (3-20 kg) (Rodr??guez-Marroyo et al., 2012) en condiciones adversas que suponen la inhalaci??n de humo (Wegesser et al., 2009), trabajar en zonas de elevada pendiente (Brotherhood et al., 1997) en condiciones de calor ambiental (Raimundo y Figueiredo, 2009; Rodr??guez-Marroyo et al., 2012). El uso a...

  2. El aprendizaje significativo en el contexto educativo

    Directory of Open Access Journals (Sweden)

    Alicia Almeida Cantoni

    2007-01-01

    Full Text Available Actualmente es posible reconocer, en diferentes ámbitos académicos, la predominancia de prácticas educativas sucedáneas o artificiales, dado que el conocimiento se valora como neutral, autosuficiente e independiente de las prácticas sociales de la cultura de las situaciones cotidianas. El resultado de este tipo de prácticas son aprendizajes desprovistos de significado y sentido, reflejando como el estudiante se torna muy poco hábil para transferir y generalizarlo que aprende. En este ejemplo de aprendizajese da lugar a una ruptura entre el saber qué (know what y el saber cómo (know how.

  3. El placer secreto

    Directory of Open Access Journals (Sweden)

    Günter Jursch

    2004-04-01

    Full Text Available Muchas enfermedades crónicas tienen un componente psicosomático. En estos casos considero más apropiado aplicar la concepción del Lejano Oriente (p. e. Taoísmo y Budismo, por ser más cercana a la realidad que la concepción occidental (influida por el cristianismo, el judaísmo y el Islam. Aplicando el punto de vista de Oriente, busco el elemento positivo en la región en la que predomina lo malo, el punto blanco en el campo negro de la enfermedad. Este elemento positivo en el campo de la enfermedad muchas veces es un placer secreto, una alegría secreta o una ventaja que se obtiene o se espera obtener mediante la enfermedad.

  4. El cerebro es la pantalla, el lenguaje es el teclado

    Directory of Open Access Journals (Sweden)

    Lucia Abreu

    2015-09-01

    Full Text Available El presente artículo surge en el marco del Seminario Filosofía de la Cultura de la Maestría en Comunicación y Cultura de la Universidad de Buenos Aires; y procuramos realizar una reflexión crítica -o al menos presentar ciertos disparadores- sobre la sociedad contemporánea. Planteamos diferentes modos de habitar el mundo desde la sociedad disciplinaria a la actual sociedad de control, con un modelo de hombre performático que vive a través de las redes sociales con el uso de los emojis o emoticones. Pensamos al sujeto (sea vulnerado o no, rico, pobre, con acceso a educación formal o no, extranjero o nativo, entre otros como un sujeto descentrado; sujeto en proceso, inmerso en una realidad no real sobre quien se imprimen efectos de realidad.

  5. Residual stresses

    International Nuclear Information System (INIS)

    Sahotra, I.M.

    2006-01-01

    The principal effect of unloading a material strained into the plastic range is to create a permanent set (plastic deformation), which if restricted somehow, gives rise to a system of self-balancing within the same member or reaction balanced by other members of the structure., known as residual stresses. These stresses stay there as locked-in stresses, in the body or a part of it in the absence of any external loading. Residual stresses are induced during hot-rolling and welding differential cooling, cold-forming and extruding: cold straightening and spot heating, fabrication and forced fitting of components constraining the structure to a particular geometry. The areas which cool more quickly develop residual compressive stresses, while the slower cooling areas develop residual tensile stresses, and a self-balancing or reaction balanced system of residual stresses is formed. The phenomenon of residual stresses is the most challenging in its application in surface modification techniques determining endurance mechanism against fracture and fatigue failures. This paper discusses the mechanism of residual stresses, that how the residual stresses are fanned and what their behavior is under the action of external forces. Such as in the case of a circular bar under limit torque, rectangular beam under limt moment, reclaiming of shafts welds and peening etc. (author)

  6. El negocio de franquicias

    OpenAIRE

    Torres, José

    2008-01-01

    El negocio de franquicias se ha constituido en un sistema comercial de mucho éxito para las empresas que desean expandirse y que no cuentan con los recursos económicos suficientes para hacerlo. En todo el mundo existen empresarios independientes esperando su oportunidad para invertir de manera segura, confiable y con una rentabilidad probada, la franquicia se constituye en una excelente alternativa. El franquiciador y el franquiciado se comprometen, mediante la firma de una contrato, a ...

  7. La influencia espartana en el Egeo y el mar Jónico en el periodo posterior a la Paz del Rey (386-374 a. C.

    Directory of Open Access Journals (Sweden)

    José Pascual

    2007-01-01

    Full Text Available Este trabajo analiza la situación en el Egeo y en el mar Jónico en el período comprendido entre la Paz del Rey (386 a.C. y la batalla de Leuctra (371 a.C., e intenta modificar la visión demasiado rígida de un imperialismo espartano excesivamente centrado en Grecia continental. Lejos de ello, Esparta se preocupó por extender su hegemonía en ambos ámbitos el Egeo y el mar Jónico.This paper analyzes the situation in the Aegean and Ionic sea during the period between the King’s Peace (386 a.C. and the battle of Leuctra (371 a.C. and intends to modify the rigid view of the Spartan imperialism excessively focused in continental Greece. Far from this consideration, Sparta tried to extend its hegemony in both regions the Aegean and Ionic Sea.

  8. Estrés y Satisfacción Familiar en estudiantes universitarios: ¿afecta el divorcio parental? || Family Stress and Satisfaction in college students: does parental divorce matter?

    Directory of Open Access Journals (Sweden)

    Laura Viqueira-Gutiérrez

    2017-07-01

    Full Text Available Esta investigación explora si el divorcio de los padres se relaciona con el estrés y la satisfacción familiares de sus hijos universitarios, así como con la calidad y la frecuencia de las relaciones padres-hijos. Participaron 147 alumnos de primer curso de las titulaciones de Educación Primaria, Educación Social, Filología, Sociología y Logopedia de la Universidade da Coruña. Los resultados indicaron que los estudiantes universitarios pertenecientes a familias en las que los padres están divorciados tienen un estrés significativamente mayor, una satisfacción familiar menor y una calidad y frecuencia de las relaciones familiares menor que los estudiantes universitarios pertenecientes a familias de padres no divorciados. Estos resultados podrían estar relacionados con los efectos a largo plazo del divorcio y ponen de manifiesto diferencias en las condiciones familiares de los alumnos cuyos padres están divorciados comparados con aquellos cuyos padres continúan casados.

  9. El IDRC en Brasil

    International Development Research Centre (IDRC) Digital Library (Canada)

    y el agua. Durante la dictadura que culminó en 1985, el IDRC ayudó a intelectuales de ideas ... terior al terremoto de 2010, seguridad alimentaria y ... La investigación en salud en el estado de São Paulo ayudó a ... Su trabajo es parte de una.

  10. El IDRC en Venezuela

    International Development Research Centre (IDRC) Digital Library (Canada)

    Tras la descentralización del sistema de salud, el Centro de ... Competition Network, la Organización para la Cooperación y el ... conocimiento con los formuladores de políticas, con otros investigadores y comunidades en todo el mundo.

  11. El debido procedimiento administrativo

    Directory of Open Access Journals (Sweden)

    Enrique Rojas Franco

    2011-12-01

    Full Text Available El presente artículo analiza la manifestación y aplicación del debidoproceso como derecho y garantía de protección, y como principio esencialen el procedimiento administrativo, el cual está basado fundamentalmente enlas resoluciones de la Sala Constitucional costarricense y en la Corte Interamericanade Derechos Humanos.

  12. Teatro: El camino

    Directory of Open Access Journals (Sweden)

    Gustavo Andrade Rivera

    1967-10-01

    Full Text Available la obra en general debe tener cierto ritmo farsesco. Adán y Eva, Caín, Sherlock Holmes y Watson, el Ministro, el hombre de la urgencia fisiológica, los Diéz Soldados y un cabo, etc., el Autor mismo, son personajes de pantomima.

  13. El IDRC en Venezuela

    International Development Research Centre (IDRC) Digital Library (Canada)

    acuicultura y sobre la formación técnica elevó la ... de decisión. Los hallazgos fueron aprove - chados por la subcomisión legislativa encargada de proponer una nueva ley de salud. La investigación de ecosalud, que estudia el ... CENTRO INTERNACIONAL DE INVESTIGACIONES PARA EL DESARROLLO. El IDRC en ...

  14. El IDRC en Brasil

    International Development Research Centre (IDRC) Digital Library (Canada)

    en 1985, el IDRC ayudó a intelectuales de ideas democráticas ... más sostenible. □ los países ... CENTRO INTERNACIONAL DE INVESTIGACIONES PARA EL DESARROLLO. El IDRC en Brasil ... a las personas y al medio ambiente. Investi-.

  15. Conjugando el presente

    Directory of Open Access Journals (Sweden)

    Héctor Rojas Herazo

    1968-06-01

    Full Text Available La añoranza suele ser, casi siempre, la línea critica de menor resistencia. El lema de que "todo tiempo pasado fue mejor" tiene un poco la culpa. En cualquier orden del conocimiento el pasado sigue el verdadero presente. Ese presente en que nos gusta respirar y vivir. Nada de compromiso circundante. Nada de inmediatez.

  16. Uso combinado de modelos de estresse no trabalho e a saúde auto-referida na enfermagem Uso combinado de modelos de estrés en el trabajo y la salud auto referida en la enfermería Combined use of job stress models and self-rated health in nursing

    Directory of Open Access Journals (Sweden)

    Rosane Härter Griep

    2011-02-01

    multidimensional que incluyó dos escalas de estrés en el trabajo (modelo demanda-control y desequilibrio esfuerzo-recompensa en 2006. Se consideraron el modelo demando y control parcial y completo (incluye apoyo social en el trabajo, así como el esfuerzo y recompensa parcial y completo (incluye exceso de compromiso con el trabajo. Se utilizaron modelos estadísticos múltiples para estimar razones de probabilidades ajustadas y sus respectivos intervalos con 95% de confianza. RESULTADOS: Las dimensiones de ambos modelos estuvieron independientemente asociadas con la salud autoreferida, con odds ratios entre 1,70 y 3,37. El modelo parcial demanda-control se mostró menos asociado a la salud (OR=1,79; IC 95% 1,26;2,53 al compararlo con el desequilibrio esfuerzo-recompensa (OR=2,27; IC 95% 1,57;3,30. La incorporación del apoyo social y del exceso de compromiso con el trabajo aumentó la fuerza de asociación de los modelos demanda-control y desequilibrio esfuerzo-recompensa, respectivamente. Se observó aumento en la fuerza de asociación al combinarse los dos modelos parciales. CONCLUSIONES: Los resultados indican mejor desempeño del modelo desequilibrio esfuerzo-recompensa para este grupo específico y para el resultado evaluado y ventaja en el uso de modelos completos o del uso combinado en modelos parciales.OBJECTIVE: To identify combinations of two models of psychosocial stress at work among nursing teams and their associations with self-rated health. METHODS: This was a cross-sectional study among workers at three public hospitals in the municipality of Rio de Janeiro, Southeastern Brazil (N = 1307. In 2006, a multidimensional questionnaire including two scales for measuring stress at work (demand-control and effort-reward imbalance models was administered. Partial and complete (including social support at work demand-control models were considered, along with partial and complete (including excessive commitment to work effort-reward models. Multiple logistic regression

  17. Desgaste físico e mental de auxiliares de enfermagem: uma análise sob o enfoque gerencial Desgaste físico y mental de auxiliares de enfermería: un análisis bajo el enfoque gerencial Mental and physical stress of auxiliary nurses: analysis of management

    Directory of Open Access Journals (Sweden)

    Moema Miranda de Siqueira

    1995-01-01

    Full Text Available Buscando melhor compreender o trabalho em organizações de saúde. Foi realizada uma pesquisa em hospitais gerais contemplando alguns grupos ocupacionais. Supõe-se que a atividade de lidar com dor, sofrimento e morte interfere na organização, gestão, condições de trabalho e que de maneira geral, expõe os trabalhadores dessas organizações a um desgaste físico e mental intenso. Percebeu-se, no entanto, que tanto as organizações quanto os próprios grupos ocupacionais têm ainda pouca consciência sobre estes problemas, desenvolvendo poucas formas de regulação ou atenuação dos conflitos daí decorrentes. O artigo apresenta uma análise específica sobre o grupo de auxiliares de enfermagem e sugere, a título de conclusivo, algumas medidas que podem melhorar essa situação.Buscando comprender mejor el trabajo en organizaciones de salud, fue realizada una investigación en hospitales generales contemplando algunos grupos ocupacionales. Se supone que una actividad ligada a dolor, sufrimiento y muerte interfiere en la organización, gestión, condiciones de trabajo y que de manera general, expone a los trabajadores de esas organizaciones a un desgaste físico y mental intenso. Se notó también, que tanto las organizaciones como los propios grupos ocupacionales aún tienen escasa conciencia sobre estos problemas, desenvolviendo pocas formas de regulación o atenuación de los conflictos decorrentes. El artículo presenta un análisis específico sobre el grupo de auxiliares de enfermería y sugiere, a título de conclusión medidas que pueden mejorar esa situación.Seeking a better understanding of job stress, auxiliary nurses were evaluated in General Hospitals Belo Horizonte. The emotional stress which accompanies auxiliary nurses caring for the sick and easing physical and mental suffering affects their own mental state and physical health. Elements that cause suffering and diseases can be attenuated or intensified depending on

  18. Modified harmony search

    Science.gov (United States)

    Mohamed, Najihah; Lutfi Amri Ramli, Ahmad; Majid, Ahmad Abd; Piah, Abd Rahni Mt

    2017-09-01

    A metaheuristic algorithm, called Harmony Search is quite highly applied in optimizing parameters in many areas. HS is a derivative-free real parameter optimization algorithm, and draws an inspiration from the musical improvisation process of searching for a perfect state of harmony. Propose in this paper Modified Harmony Search for solving optimization problems, which employs a concept from genetic algorithm method and particle swarm optimization for generating new solution vectors that enhances the performance of HS algorithm. The performances of MHS and HS are investigated on ten benchmark optimization problems in order to make a comparison to reflect the efficiency of the MHS in terms of final accuracy, convergence speed and robustness.

  19. Modified puestow lateral pancreaticojejunostomy.

    Science.gov (United States)

    Ceppa, Eugene P; Pappas, Theodore N

    2009-05-01

    There are various surgical options for the treatment of pain associated with chronic pancreatitis. The modified Puestow lateral pancreaticojejunostomy has been proven to be effective in ameliorating symptoms and expediting return to normal lifestyle while maintaining a low rate of morbidity and mortality. However, the debate regarding which surgical treatment provides the best outcomes is controversial. The aims of this manuscript are to identify the patient population for which the Puestow benefits the most and discuss the pertinent technical aspects of the surgical procedure.

  20. 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.

  1. Prevalência de fatores de risco de natureza modificável para a ocorrência de diabetes mellitus tipo 2 Predominio de factores de riesgo posibles de modificar en el acontecimiento de diabetes tipo 2 Prevalence of risk factors that can be modified into the occurrence of type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Rosa Maria Fernandes Vilarinho

    2008-09-01

    Full Text Available Estudo transversal realizado com estudantes universitários do curso de Enfermagem para identificação de fatores de risco para o diabetes tipo 2. Em relação ao nível de risco: 65% apresentavam risco baixo, 27%, risco zero, enquanto 7,5% exibiam risco alto. A história familiar de diabetes e hipertensão foi identificada em 45% da amostra. A prevalência de sedentarismo foi igual a 75%; de sobrepeso, igual a 15%, e de obesidade (IMC e ³25 kg/m², igual a 5%. Verificaram-se ainda um menor consumo de alimentos ricos em fibras e o aumento do consumo de alimentos ricos em gorduras. Os dados levantados apontaram para a necessidade de investimentos em ações de promoção à saúde dentro da própria unidade de formação, como a criação de espaços próprios destinados à valorização da aquisição de novas práticas de saúde, através da ênfase à prática da atividade física, e incentivo à aquisição de hábitos alimentares saudáveis.El estudio enfadado realizado cerca de estudiantes de universidad del curso de enfermería, para la identificación de factores del riesgo para la diabetes tipo 2. En cuanto al nivel de riesgo: el 65 % presentaba bajo el riesgo, el 27 % marco el cero, mientras el 7,5 % mostraba el riesgo alto. La historia cerca de diabetes y hipertensión fue identificada en el 45 % de la muestra. El predominio de: el sedentarismo era el mismo al 75 %; de la sobrecarga igual al 15 %, y de la obesidad (CMI e" 25 kg/m2 igualan al 5 %. Menos consumo de la comida rica pasó todavía en fibras y el aumento del consumo de la comida rica en grasa. Los datos levantados señalaran la necesidad de inversiones en acciones de promoción a la salud dentro de la misma unidad de formación, como la creación de propios espacios destinados, el aumento del valor de la adquisición de nuevas prácticas de la salud, por el énfasis la práctica de la actividad física y incentivo a la adquisición de alimenticios saludables.Cross study

  2. Stress related to care: the impact of childhood cancer on the lives of parents Estrés relacionado al cuidado: el impacto del cáncer infantil en la vida de los padres Estresse relacionado ao cuidado: o impacto do câncer infantil na vida dos pais

    Directory of Open Access Journals (Sweden)

    Daniela Fernanda dos Santos Alves

    2013-02-01

    Full Text Available OBJECTIVES: The objective was to assess the stress levels of parents of children with cancer and to identify correlations among demographic data and anxiety levels. METHODS: A descriptive, cross-sectional study, conducted in two Brazilian institutions, with 101 parents of children with cancer. Through interviews, parents responded to two instruments: Pediatric Inventory for Parents - Brazilian version, which assesses stress levels, and State-Trait Anxiety Inventory, for the measurement of anxiety. The correlations between the instruments and the sociodemographic variables of the parents and children were evaluated using the Spearman correlation coefficient. RESULTS: Higher levels of stress and anxiety were seen by young parents, young children and with less time since diagnosis. The fear of death and the disease impact on the life of a child were the events considered the most stressful for the parents . CONCLUSIONS: In clinical practice, the nurse who can identify the occurrence of these symptoms becomes capable of planning nursing care that includes the family in decisions about the care. Moreover, she can provide support to help parents manage their stress levels and positively face the illness of their children.OBJETIVOS: El objetivo fue evaluar el nivel de estrés de los padres de niños con cáncer e identificar correlaciones entre los datos sociodemográficos y los niveles de ansiedad. MÉTODO: Estudio descriptivo transversal, realizado en dos instituciones brasileñas, con 101 padres de niños con cáncer. A través de entrevista, los padres contestaron a dos instrumentos: Pediatric Inventory for Parents - versión brasileña, que evalúa niveles de estrés, e Inventário de Ansiedade Traço-Estado, para medir la ansiedad. Las correlaciones entre los instrumentos y las variables sociodemográficas de los padres y de los niños fueron evaluados por el Coeficiente de Correlación de Spearman. RESULTADOS: Los más altos niveles de estrés y

  3. new concepts of a modified hall - petch type relationship

    African Journals Online (AJOL)

    NIJOTECH

    Abstract. A modified form of the Hall - Perch equation, where the average grain diameter is replaced by the surface to volume ratio of internal boundaries (Sv), is considered. Working with this model, a flow stress – Sv relationship dominated by geometrically necessary dislocations (GNDs) is derived for the low strain region.

  4. Work Stress

    OpenAIRE

    Roeters, Anne

    2014-01-01

    Most of us agree that stress is a growing problem within organizations. We hear about the postal workers who had killed fellow employees and supervisors, and then hear that a major cause of tension is at work. Friends tell us that they are stressed due to increased workload and he has to work overtime because the company is restructured. We read the polls that employees complain about the stress in trying to balance family life with the work. Stress is a dynamic condition in which an individu...

  5. Preparação psicológica e o estresse de crianças submetidas a cirurgias Preparación psicológica y el estrés de los niños sometidos a cirugía Psychological preparation and stress of children undergoing surgery

    Directory of Open Access Journals (Sweden)

    Camilla Volpato Broering

    2011-03-01

    Full Text Available Este artigo tem por objetivo apresentar uma pesquisa que avaliou os efeitos da preparação psicológica pré-cirúrgica sobre o estresse de crianças submetidas a cirurgias eletivas em que foram utilizados dois programas distintos de preparação. A pesquisa foi realizada com 30 participantes, divididos em dois grupos, usuários de um hospital infantil, e nela utilizou-se a Escala de Estresse Infantil (ESI. A pesquisa compreendeu três etapas distintas: a aplicação da ESI antes da preparação, no dia anterior à cirurgia; b a preparação propriamente dita, sendo ambos os grupos submetidos aos diferentes programas de preparação; e c a reaplicação da ESI, depois da preparação. Os resultados mostraram que há significativa redução do nível de estresse depois da preparação, embora não tenha havido diferença significativa quanto ao tipo de programa utilizado. Há implicações práticas no atendimento psicológico das crianças em situação pré-cirúrgica e limitações a serem consideradas quando se pesquisa esta área da psicologia pediátrica.Este artículo tiene como objetivo presentar un estudio que evaluó los efectos de la preparación psicológica pre-quirúrgica sobre el estrés en niños sometidos a cirugía electiva, con dos programas de preparación. La investigación se llevó a cabo con 30 participantes, divididos en dos grupos, los usuarios de un hospital de niños y se utiliza la Escala de Estrés infantil (ESI. Hubo tres fases distintas: a Aplicación de ESI antes de la preparación, el día antes de la cirugía, b la preparación en sí, en ambos grupos presentaron a diferentes programas de preparación, y c una reaplicación de ESI, después de la preparación. Los resultados mostraron que la reducción significativa en el nivel de estrés después de la preparación, aunque no hubo diferencias significativas en el tipo de programa utilizado. Hay implicaciones prácticas para la situación psicológica de los ni

  6. Resultados del cabestrillo suburetral transobturatriz con cinta de polipropileno para el tratamiento quirúrgico de la incontinencia de orina de esfuerzo Results obtained with the trans-obturation subureteral sling procedure with polypropylen3 strip for surgical treatment of stress urinary incontinence

    Directory of Open Access Journals (Sweden)

    Radamés Isaac Adefna Pérez

    2011-09-01

    Full Text Available Introducción: la incontinencia urinaria de esfuerzo constituye un problema frecuente en el sexo femenino, con una prevalencia de un 30 %. Aunque no es letal, provoca un impacto importante en las esferas psíquica, social y económica para las que la padecen. Objetivo: demostrar la posibilidad de realizar la técnica de cabestrillo suburetral transobturatriz con medios propios sin afectar la continencia ni seguridad de la paciente. Métodos: se realizó un estudio descriptivo y prospectivo para evaluar las principales variables demográficas y el impacto en la calidad de vida y continencia mediante la escala Cuestionario de Calidad de Vida para Pacientes con Incontinencia Urinaria, Forma corta. Resultados: fueron intervenidas 36 pacientes con un seguimiento de 12 meses. La edad promedio es de 51,2 años, con predominio de las de edades posmenopáusicas y multíparas. Todas presentaban incontinencia de esfuerzo genuina o mixta. Se comprobó una mejoría significativa del puntaje preoperatorio con el posoperatorio. El porcentaje de éxitos al año fue de un 86,1 %. La principal complicación fue la erosión de prótesis e infecciones urinarias. Conclusiones: la realización del cabestrillo suburetral con prótesis por vía transobturatriz es una opción real y factible de ser realizada en nuestro país en pacientes con incontinencia urinaria de esfuerzo o mixta, pues logra una continencia similar a otras técnicas, con una morbilidad menor y un ahorro económico significativo.Introduction: the stress urinary incontinence is a frequent problem in the female sex with a prevalence of 30 %. Although is not lethal it to provokes a significant impact on the psychic, social and economic spheres for those suffering this disease. Objective: to demonstrate the chance of performing the trans-obturation subureteral sling procedure with own means without involve the continence and the safety of patient. Methods: a prospective and descriptive study was

  7. Forest die-back modified plankton recovery from acidic stress

    Czech Academy of Sciences Publication Activity Database

    Vrba, J.; Kopáček, Jiří; Fott, J.; Nedbalová, L.

    2014-01-01

    Roč. 43, č. 2 (2014), s. 207-217 ISSN 0044-7447 R&D Projects: GA ČR(CZ) GA206/07/1200; GA ČR(CZ) GAP504/12/1218 Institutional support: RVO:60077344 Keywords : atmospheric acidification * Bohemian Forest * lake recovery * phytoplankton * zooplankton Subject RIV: DJ - Water Pollution ; Quality Impact factor: 2.289, year: 2014

  8. A dor da queimadura: terrível para quem sente, estressante para quem cuida El dolor de la quemadura: terrible para quien siente estresante para quien cuida Burn pain: terrible for the ones who feel, stressful for the ones who care

    Directory of Open Access Journals (Sweden)

    Lídia Aparecida Rossi

    2000-07-01

    Full Text Available Os objetivos deste foram identificar os significados culturais atribuídos pela equipe de enfermagem às manifestações de dor apresentadas pelos pacientes portadores de queimaduras e identificar as percepções dos pacientes frente à dor provocada pela queimadura e à assistência de enfermagem prestada nestas situações. Foram realizadas observações participantes e entrevistados quatro enfermeiros, cinco auxiliares e 12 pacientes, em uma unidade de queimados. A dor da queimadura foi compreendida pelos enfermeiros como: física e emocional. Para todos os profissionais o banho e curativo são procedimentos estressantes. Para os pacientes a dor é terrível e não pode ser explicada, mas necessita ser suportada.Los objetivos de este estudio fueron identificar los significados culturales que el equipo de enfermería atribuye a las manifestaciones de dolor expresadas por los pacientes portadores de quemadura e identificar las percepciones de los mismos frente al dolor provocado por la quemadura y la atención de enfermería prestada en estas condiciones. Fueron realizadas observaciones participantes y entrevistados cuatro enfermeros, cinco auxiliares y 12 pacientes en una Unidad de Quemados. El dolor de la quemadura fue comprendido por los enfermeros como: física y emocional. Para todos los profesionales y pacientes el baño y la curación son procedimientos estresantes. Para los pacientes el dolor es terrible y no consiguen explicarlo, pero deben soportarlo.The goals of the study were to understand the cultural meaning that the nursing team and burn patients attribute to burn pain. Participant observations were carried out during one year at a Burn Unit. Semi-structured interviews with four nurses, five nursing auxiliaries and 12 patients were recorded. The burn pain is understood by nurses as physical and emotional pain. For professionals and patients, bath and dressing changes are stressful. For patients, burn pain is terrible and they can

  9. El Pulpo. Caracas

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1961-01-01

    Full Text Available El estrecho valle donde el conquistador Diego de Losada fundó a Caracas, contenía hasta hace poco una población de 150.000 habitantes. Ni las distancias ni el tiempo preocupaban a los moradores. El peatón era todavía el dueño de la ciudad. Vivía cerca de su trabajo. Su traslado no se transformaba, como hoy, en pérdida de tiempo y gastos de energías.

  10. El primer libro colombiano

    Directory of Open Access Journals (Sweden)

    Juan Friede

    1961-12-01

    Full Text Available En el año 1537 pasó por Cartagena con rumbo a Nueva España (México el clérigo Juan Pérez Materano, designado por la Corte para ocupar el cargo de chantre de la catedral de aquel reino. Unos meses antes había regresado a Cartagena de su expedición a las sierras de Abibe, el capitán Francisco de César, el cual trajo extraordinarias noticias sobre ricas minas de oro que había encontrado.

  11. El lenguaje posmoderno

    Directory of Open Access Journals (Sweden)

    García, Andrés

    1991-12-01

    Full Text Available This article is a proposal for the systematical analysis of modernity and postmodernity, through the different stages of work. It begins with the language, not only verbal but also communicational of all cultural phenomena and specifically of Architecture.

    El presente artículo hace una propuesta para el análisis sistemático de la modernidad y posmodernidad, a través de los diferentes puntos del trabajo. Se inicia con el lenguaje, no sólo verbal, sino el comunicacional de todo fenómeno cultural y específicamente el de la arquitectura.

  12. Estudiando el Tropicalismo

    OpenAIRE

    Larrique P., Diego

    2015-01-01

    En mayo de 1968 ¡qué fecha! Se edita el disco / manifiesto “Tropicalia, Panis et circenses”, que recoge un esfuerzo colectivo de síntesis del naciente movimiento Tropicalista. Entendido como la recuperación de la línea evolutiva de la música popular brasilera, el Tropicalismo pretendió retomar el impulso que la Bossa Nova había supuesto en el panorama musical brasilero desde la aparición del disco “Chega de Saudade” de Joao Gilberto en 1958. El trabajo que aquí se presenta intenta re...

  13. El postfeudalismo mexicano

    OpenAIRE

    Emilio Velazco Gamboa

    2007-01-01

    Este trabajo analiza las estructuras políticas y económicas de México para identificar y describir el fenómeno del postfeudalismo. A partir de un marco teórico de raíz sociohistórica, que recoge los elementos esenciales del feudalismo, el autor realiza una crítica directa al poder y sus engranajes políticos. Lo que se descubre es un sistema basado en el clientelismo, donde se impone el fraude y la compra de voluntades. El resultado es una situación de quiebra de la democracia, cuyo último cap...

  14. El paisaje como estructura

    OpenAIRE

    López Bravo, Celia

    2017-01-01

    Este ejercicio final de carrera abarca el proyecto de un nuevo cementerio en Málaga. Desde el análisis del lugar y el estudio de las prácticas funerarias en relación con la cultura urbana, hacia una propuesta concreta y su posterior desarrollo técnico. La posición de una ciudad ante la muerte revela interioridades religiosas, sociales, económicas y en definitiva culturales. En el caso de las zonas urbanas andaluzas, es latente el distanciamiento (no solo físico) entre la ciudad y est...

  15. El otro Sabio, el otro saber

    Directory of Open Access Journals (Sweden)

    Antonio Silvera Arenas

    2005-01-01

    Full Text Available En este artículo, el autor tiende un puente para conectar a “el Sabio Catalán”, Ramón Vinyes i Cluet, con aquel cómplice suyo de las tertulias del Centro de Barranquilla, José Felix Fuenmayor, que participa en la aventura literaria de la revista Voces, uno de los grandes exponentes de la letras colombianas del siglo XX, a quien Silvera llama “el Otro Sabio”

  16. Resilience of cereal crops to abiotic stress: A review

    African Journals Online (AJOL)

    SAM

    2014-07-16

    Jul 16, 2014 ... Key words: Cereal crops, abiotic stresses, food insecurity, molecular breeding, quantitative trait loci (QTLs), salinity, water stress. ... production of genetically modified (GM) crops, exo- genous use of osmo protectants etc. ... stressful environments is important to fulfill food demand of the ever-increasing world ...

  17. El florero de Llorente

    Directory of Open Access Journals (Sweden)

    Arturo Abella

    1962-02-01

    Full Text Available No nos cause admiración ni desasosiego, ni sarampión, ni reuma la afirmación de que el libro de Arturo Abella "El Florero de Llorente", ha sido para desconsuelo de muchos, el éxito del año. Acostumbrado, como tenemos el paladar a los sabores flojos e ingenuos de los textos de historia, no es extraño que este libro, digestivo y potable, sorprendiera nuestro gusto y al cabo de pocas páginas de su lectura avivara el interés por los hechos patrios y con el hambre y la sed de saborearlos hundiéramos hasta la terminación del mismo, nuestra atención, como quien sumerge la mano en un estanque y se refresca el cuerpo con una sensación difícil de escribir.

  18. Early life stress induces long-term changes in limbic areas of a teleost fish: the role of catecholamine systems in stress coping

    DEFF Research Database (Denmark)

    Vindas, Marco A.; Fokos, Stefanos; Pavlidis, Michail

    2018-01-01

    Early life stress (ELS) shapes the way individuals cope with future situations. Animals use cognitive flexibility to cope with their ever-changing environment and this is mainly processed in forebrain areas. We investigated the performance of juvenile gilthead seabream, previously subjected...... of post-stress response in the β2 adrenergic receptor expression and a downregulation in bdnf in the Dm3 of ELS fish, which together indicate an allostatic overload in their stress coping ability. ELS fish showed higher neuronal activity (cfos) post-acute stress in the hippocampus homologue (Dlv...

  19. Effects of specimen size and crack depth ratio on calibration curves for modified compact tension specimens

    Czech Academy of Sciences Publication Activity Database

    Seitl, Stanislav; Viszlay, V.; Cifuentes, H.; Canteli, A.

    2015-01-01

    Roč. 15, č. 2 (2015) ISSN 1804-4824 Institutional support: RVO:68081723 Keywords : Modified compact tension test * fracture * concrete * core drill * stress intensity factor Subject RIV: JL - Materials Fatigue, Friction Mechanics

  20. Residual stresses

    International Nuclear Information System (INIS)

    Macherauch, E.

    1978-01-01

    Residual stresses are stresses which exist in a material without the influence of external powers and moments. They come into existence when the volume of a material constantly changes its form as a consequence of mechanical, thermal, and/or chemical processes and is hindered by neighbouring volumes. Bodies with residual stress are in mechanical balance. These residual stresses can be manifested by means of all mechanical interventions disturbing this balance. Acoustical, optical, radiological, and magnetical methods involving material changes caused by residual stress can also serve for determining residual stress. Residual stresses have an ambivalent character. In technical practice, they are feared and liked at the same time. They cause trouble because they can be the cause for unexpected behaviour of construction elements. They are feared since they can cause failure, in the worst case with catastrophical consequences. They are appreciated, on the other hand, because, in many cases, they can contribute to improvements of the material behaviour under certain circumstances. But they are especially liked for their giving convenient and (this is most important) mostly uncontrollable explanations. For only in very few cases we have enough knowledge and possibilities for the objective evaluation of residual stresses. (orig.) [de

  1. El docente ante el oficio de investigar en el aula

    Directory of Open Access Journals (Sweden)

    José Ignacio Bolaños Motta

    2016-10-01

    Full Text Available El presente escrito está inspirado en la canción titulada La fábula de los tres hermanos, del cantautor cubano Silvio Rodríguez Domínguez. Se espera que a través de estos tres apartes de la letra de esta canción, consecuentemente seleccionados, se genere una reflexión en torno a la actividad de generar proyectos de investigación en la escuela secundaria, o como se suele denominar actualmente investigación en el aula, al respecto se abordan las complicaciones, tópicos y demás problemáticas que eventualmente se pueden presentar en la multiplicidad de compromisos cotidianos ante los cuales se ve enfrentado el docente, al momento de desarrollar un proyecto de investigación en una comunidad educativa desde la metodología de la etnografía, hoy usada en los modelos de investigación en educación y pedagogía. Este documento tiene por objetivo generar una reflexión en torno a la mirada del maestro de escuela secundaria, ante el acto de investigar su contexto escolar de trabajo, y el papel de las universidades, en lo que concierne a la formación de licenciados con competencias en investigación educativa.

  2. Modified Dugdale cracks and Fictitious cracks

    DEFF Research Database (Denmark)

    Nielsen, Lauge Fuglsang

    1998-01-01

    A number of theories are presented in the literature on crack mechanics by which the strength of damaged materials can be predicted. Among these are theories based on the well-known Dugdale model of a crack prevented from spreading by self-created constant cohesive flow stressed acting in local...... areas, so-called fictitious cracks, in front of the crack.The Modified Dugdale theory presented in this paper is also based on the concept of Dugdale cracks. Any cohesive stress distribution, however, can be considered in front of the crack. Formally the strength of a material weakened by a modified...... Dugdale crack is the same as if it has been weakened by the well-known Griffith crack, namely sigma_CR = (EG_CR/phi)^1/2 where E and 1 are Young's modulus and crack half-length respectively, and G_CR is the so-called critical energy release rate. The physical significance of G_CR, however, is different...

  3. Geopotential Stress

    DEFF Research Database (Denmark)

    Schiffer, Christian; Nielsen, S.B.

    Density heterogeneity in the Earth’s lithosphere causes lateral pressure variations. Horizontal gradients of the vertically integrated lithostatic pressure, the Geopotential Energy (GPE), are a source of stresses (Geopotential Stress) that contribute to the Earth’s Stress Field. In theory the GPE...... is linearly related to the lithospheric part of the Geoid. The Geopotential Stress can be calculated if either the density structure and as a consequence the GPE or the lithospheric contribution to the Geoid is known. The lithospheric Geoid is usually obtained by short pass filtering of satellite Geoid...... are not entirely suitable for the stress calculations but can be compiled and adjusted. We present an approach in which a global lithospheric density model based on CRUST2.0 is obtained by simultaneously fitting topography and surface heat flow in the presence of isostatic compensation and long-wavelength lateral...

  4. Bitumen based modified substance

    International Nuclear Information System (INIS)

    Kostolanyi, P.

    1987-01-01

    The necessary amounts of tetrahydrosilicic acid and methyl phenyl silicon oil are added to molten bitumen heated to temperatures of 50 to 200 degC. The mixture is thoroughly mixed and let to cool. The structure of the product comes close to gel and its properties (penetration, softening point, workability time, penetration index) may be changed in dependence on the amount of additions and on the time and temperature of heating. The advantage of the thus prepared modified material is its shorter workability time, its ability to bind materials with a certain water content, and its relatively low price. It may be used for fixing and storing low-and medium-level radioactive organic and thickened waste waters. (E.S.)

  5. Biodegradable modified Phba systems

    International Nuclear Information System (INIS)

    Aniscenko, L.; Dzenis, M.; Erkske, D.; Tupureina, V.; Savenkova, L.; Muizniece - Braslava, S.

    2004-01-01

    Compositions as well as production technology of ecologically sound biodegradable multicomponent polymer systems were developed. Our objective was to design some bio plastic based composites with required mechanical properties and biodegradability intended for use as biodegradable packaging. Significant characteristics required for food packaging such as barrier properties (water and oxygen permeability) and influence of γ-radiation on the structure and changes of main characteristics of some modified PHB matrices was evaluated. It was found that barrier properties were plasticizers chemical nature and sterilization with γ-radiation dependent and were comparable with corresponding values of typical polymeric packaging films. Low γ-radiation levels (25 kGy) can be recommended as an effective sterilization method of PHB based packaging materials. Purposely designed bio plastic packaging may provide an alternative to traditional synthetic packaging materials without reducing the comfort of the end-user due to specific qualities of PHB - biodegradability, Biocompatibility and hydrophobic nature

  6. Modified Clipped LMS Algorithm

    Directory of Open Access Journals (Sweden)

    Lotfizad Mojtaba

    2005-01-01

    Full Text Available Abstract A new algorithm is proposed for updating the weights of an adaptive filter. The proposed algorithm is a modification of an existing method, namely, the clipped LMS, and uses a three-level quantization ( scheme that involves the threshold clipping of the input signals in the filter weight update formula. Mathematical analysis shows the convergence of the filter weights to the optimum Wiener filter weights. Also, it can be proved that the proposed modified clipped LMS (MCLMS algorithm has better tracking than the LMS algorithm. In addition, this algorithm has reduced computational complexity relative to the unmodified one. By using a suitable threshold, it is possible to increase the tracking capability of the MCLMS algorithm compared to the LMS algorithm, but this causes slower convergence. Computer simulations confirm the mathematical analysis presented.

  7. Modified arthroscopic Brostrom procedure.

    Science.gov (United States)

    Lui, Tun Hing

    2015-09-01

    The open modified Brostrom anatomic repair technique is widely accepted as the reference standard for lateral ankle stabilization. However, there is high incidence of intra-articular pathologies associated with chronic lateral ankle instability which may not be addressed by an isolated open Brostrom procedure. Arthroscopic Brostrom procedure with suture anchor has been described for anatomic repair of chronic lateral ankle instability and management of intra-articular lesions. However, the complication rates seemed to be higher than open Brostrom procedure. Modification of the arthroscopic Brostrom procedure with the use of bone tunnel may reduce the risk of certain complications. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  8. Modified circular velocity law

    Science.gov (United States)

    Djeghloul, Nazim

    2018-05-01

    A modified circular velocity law is presented for a test body orbiting around a spherically symmetric mass. This law exhibits a distance scale parameter and allows to recover both usual Newtonian behaviour for lower distances and a constant velocity limit at large scale. Application to the Galaxy predicts the known behaviour and also leads to a galactic mass in accordance with the measured visible stellar mass so that additional dark matter inside the Galaxy can be avoided. It is also shown that this circular velocity law can be embedded in a geometrical description of spacetime within the standard general relativity framework upon relaxing the usual asymptotic flatness condition. This formulation allows to redefine the introduced Newtonian scale limit in term of the central mass exclusively. Moreover, a satisfactory answer to the galactic escape speed problem can be provided indicating the possibility that one can also get rid of dark matter halo outside the Galaxy.

  9. El cuento infantil: el ratoncito estudiante

    Directory of Open Access Journals (Sweden)

    Fanny Osorio

    1979-05-01

    Full Text Available Chepín era un ratoncito muy inteligente y estudioso. Madrugaba todos los días a leer los periódicos que llegaban a la tienda de la esquina. Se hizo amigo de don José, el limpiabotas, quien le permitía hojear las revistas que el anciano coleccionaba para entretenerse leyendo aventuras en los ratos de descanso.

  10. Can we control El Nino?

    International Nuclear Information System (INIS)

    MacMynowski, Douglas G

    2009-01-01

    The question of whether it is possible to intentionally modify the El Nino/Southern oscillation (ENSO) cycle is explored as a case study in the dynamics of climate intervention beyond simple temperature adjustment. A plausible control strategy is described, including an estimate of the energy it would require to implement. The intent here is not to suggest that we should do so, but rather that the scale of the required intervention is such that we could intentionally influence ENSO. Simulations use the Cane-Zebiak intermediate complexity model, and demonstrate that depending on the parameter regime, a feedback strategy that dynamically deflects less than 1% of the sunlight over the Nino-3 region of the eastern tropical Pacific could be used to reduce the probability of extreme ENSO events (T>2 deg. C) to near zero, or conversely to enhance the cycle.

  11. Learn to manage stress

    Science.gov (United States)

    Stress - managing; Stress - recognizing; Stress - relaxation techniques ... LEARN TO RECOGNIZE STRESS The first step in managing stress is recognizing it in your life. Everyone feels stress in a different way. ...

  12. Donde habite el olvido

    Directory of Open Access Journals (Sweden)

    Campo Puerta, Pilar del

    2015-07-01

    Full Text Available El desarrollo de las nuevas tecnologías de la información y de la comunicación y su plena inserción en la vida personal y profesional ha traído consigo, además de un cambio en los modos de trabajo y de interrelación humana, la amplitud y/o modificación de los significados de algunos términos. El concepto de ‘olvido’ es uno de tantos. Este trabajo aborda dos áreas antagónicas del olvido con respecto a las nuevas tecnologías de la información y la comunicación: el olvido como la necesidad de que ‘Internet se olvide de mí’, y el olvido como la amenaza que puede verse paliada apoyándose en las posibilidades que Internet aporta. En primer lugar, se exponen los significados del término ‘olvido’. A continuación y pese a ser un problema global, nos centramos principalmente en las diferentes iniciativas en el marco de la Unión Europea en general y de España en particular, que se están llevando a cabo para regular el almacenamiento de información en la red y el derecho que el ciudadano tiene para reclamar el borrado de datos personales que atenten contra su intimidad y reputación. Por último, se analiza el estímulo terapéutico que los nuevos recursos tecnológicos pueden ofrecer para el tratamiento de enfermedades donde habita el olvido como son el Alzheimer y la amnesia.

  13. Relaciones entre el Congreso Nacional y el Poder Judicial: La Importancia de la Apertura

    Directory of Open Access Journals (Sweden)

    Sebastián Soto Velasco

    2007-01-01

    Full Text Available El presente trabajo analiza las relaciones entre el Congreso Nacional y el Poder Judicial a través de dos instituciones existentes en nuestro ordenamiento: el proceso de nombramiento de Ministros de la Corte Suprema y los informes que esta última envía al Congreso Nacional en ciertos proyectos de ley. En el caso de las nominaciones de Ministros a la Corte Suprema se estudia como ha operado el sistema desde la incorporación del Senado en 1997 hasta el año 2005. Se analiza cómo la transparencia del proceso, la posibilidad de conocer la historia profesional del nominado y audiencias abiertas contribuirían a incentivar una decisión centrada en criterios de calidad. El documento también se centra en el contenido y la influencia de los informes que envía la Corte Suprema al Congreso Nacional con ocasión de la tramitación de proyectos de ley que contienen normas que modifican la organización o atribuciones de los tribunales de justicia. En esta instancia, permitir el acceso a los informes también tendría positivas consecuencias. En definitiva, aunque hay otras vías de comunicación entre el Congreso y el Poder Judicial, se profundiza únicamente en las mencionadas pues del estudio se concluye que ambas tenderían a aumentar el potencial que de suyo ya tienen si se incorpora apertura en los procesosThis paper analyzes the relationship between the Chilean Congress and Judicial power, focusing on two institutions: the nomination process to appoint Supreme Court justices and the reports that the Supreme Court is constitutionally obligated to send to the Congress when specific types of bills are introduced. The appointment of Supreme Court candidates is studied from the Senate's incorporation in the process from 1997 until 2005. The author states that a more transparent process, including the publication of the candidate's backgrounds and public hearings, would increase the incentives to nominate the most qualified candidates. The paper also

  14. Studies oriented to optimize the image quality of the small animal PET: Clear PET, modifying some of the parameters of the reconstruction algorithm IMF-OSEM 3D on the data acquisition simulated with GAMOS; Estudios para la optimizaciOn de la calidad de imagen en el escaner ClearPET, modifi cando parametros del algoritmo IMF-OSEM 3D sobre adquisiciones simuladas con GAMOS

    Energy Technology Data Exchange (ETDEWEB)

    Canadas, M.; Mendoza, J.; Embid, M.

    2007-09-27

    This report presents studies oriented to optimize the image quality of the small animal PET: Clear- PET. Certain figures of merit (FOM) were used to assess a quantitative value of the contrast and delectability of lesions. The optimization was carried out modifying some of the parameters in the reconstruction software of the scanner, imaging a mini-Derenzo phantom and a cylinder phantom with background activity and two hot spheres. Specifically, it was evaluated the incidence of the inter-update Metz filter (IMF) inside the iterative reconstruction algorithm 3D OSEM. The data acquisition was simulated using the GAMOS framework (Monte Carlo simulation). Integrating GAMOS output with the reconstruction software of the scanner was an additional novelty of this work, to achieve this, data sets were written with the list-mode format (LMF) of ClearPET. In order to verify the optimum values obtained, we foresee to make real acquisitions in the ClearPET of CIEMAT. (Author) 17 refs.

  15. Evaluation of Computational Fluids Dynamics (CFD) code Open FOAM in the study of the pressurized thermal stress of PWR reactors. Comparison with the commercial code Ansys-CFX; Evaluacion del codigo de Dinamica de Fluidos Computacional (CFD) Open FOAM en el estudio del estres termico presurizado de los reactores PWR. Comparacion con el codigo comercial Ansys-CFX

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, M.; Barrachina, T.; Miro, R.; Verdu Martin, G.; Chiva, S.

    2012-07-01

    In this work is proposed to evaluate the potential of the OpenFOAM code for the simulation of typical fluid flows in reactors PWR, in particular for the study of pressurized thermal stress. Test T1-1 has been simulated , within the OECD ROSA project, with the objective of evaluating the performance of the code OpenFOAM and models of turbulence that has implemented to capture the effect of the thrust forces in the case study.

  16. El postfeudalismo mexicano

    Directory of Open Access Journals (Sweden)

    Emilio Velazco Gamboa

    2007-01-01

    Full Text Available Este trabajo analiza las estructuras políticas y económicas de México para identificar y describir el fenómeno del postfeudalismo. A partir de un marco teórico de raíz sociohistórica, que recoge los elementos esenciales del feudalismo, el autor realiza una crítica directa al poder y sus engranajes políticos. Lo que se descubre es un sistema basado en el clientelismo, donde se impone el fraude y la compra de voluntades. El resultado es una situación de quiebra de la democracia, cuyo último capítulo ha sido el dudoso proceso electoral de julio de 2006.

  17. Escrito sobre el cuerpo

    Directory of Open Access Journals (Sweden)

    Antonio Malalana Ureña

    2013-09-01

    Full Text Available El catálogo, en una edición bilingüe español-inglés, es una pequeña guía de la exposición Shirin Neshat. Escrito sobre el cuerpo, muestra que se integra dentro de los actos de PHOTOESPAÑA13, el festival internacional de fotografía y artes visuales. El esquema del libro es sencillo y los textos son extremadamente divulgativos. El primero de ellos, Escrito sobre el cuerpo (pp. 10-15, cuyo autor es Octavio Zaya, comisario de la exposición, resume la trayectoria de esta intelectual, que "interactúa" con la fotografía y los formatos audiovisuales, y nos presenta la argumentación narrativa de los documentos expuestos, contextualizando la obra recopilada.

  18. El Fondo Buscaglione

    Directory of Open Access Journals (Sweden)

    Asociación Pro-Rescate de Archivos de Arquitectura

    2004-05-01

    Full Text Available Al ser firmado el concordato con la Santa Sede en 1887, se otorgaron facilidades a la iglesia colombiana para establecer órdenes religiosas en el territorio nacional: la jerarquía eclesiástica quedó conformada por el clero regular o diocesano y el de las comunidades. El primero atendía la feligresía en general, mientras los segundos, conforme al concordato, se consagraban a la educación, la caridad y la misiones. Entre los archivos colombianos de arquitectura que se conservan de la primera mitad del siglo XX, está el de la comunidad salesiana del Colegio León XIII de Bogotá, recopilado por su actual padre rector, Mario Peresson Tonelli, promotor del impecable trabajo de restauración del templo carmelitano de Giovanni Bucaglione.

  19. para mejorar el %R

    Directory of Open Access Journals (Sweden)

    Alfredo Díaz Mata

    2001-01-01

    Full Text Available En este trabajo se revisan dos indicadores técnicos bursátiles que están estrechamente relacionados, el oscilador estocástico %K de Lane y el oscilador %R de Williams; asimismo, se evalúa el uso de dos mecanismos asociados con el primero y que no suelen utilizarse con el %R: el proceso de frenado (slowing y el uso de un promedio móvil del propio oscilador estocástico como disparadores de señales de compra y de venta. Realizando simulaciones con 27 acciones y el Índice de Precios y Cotizaciones de la Bolsa Mexicana de Valores se verifica la hipótesis principal y se comprueba que, efectivamente, en muchos casos, el uso del proceso de frenado con el oscilador %R de Williams permite tomar mejores decisiones. Por otro lado, se concluye que de los dos disparadores de señales el que mejor funciona, tanto para %K como para %R es el uso de cotas inferior y superior. Este artículo surgió en el curso de una investigación sobre el análisis técnico bursátil de acciones que se puede realizar en su totalidad por computadora y que, esencialmente, excluye el análisis gráfico. Uno de los propósitos del estudio es determinar si es posible, y bajo qué mecanismos, establecer un sistema de análisis bursátil que le permita al inversionista tomar decisiones de inversión en acciones en la Bolsa Mexicana de Valores sin tener que emplear la considerable cantidad de tiempo que es necesario para el análisis gráfico tradicional. Durante este estudio se realizó un análisis preliminar de unos 120 indicadores técnicos para, por un lado, conocerlos con cierto detalle y, por otra parte, aislar aquellos que prometían ser de utilidad para el objetivo de la investigación. Fue en este proceso cuando se detectó que existen dos indicadores que están relacionados y que permiten un análisis por separado que tiene, cuando menos, dos ventajas. En primer lugar está el placer que da a quien gusta de estos temas encontrarse con indicadores que, de acuerdo

  20. El museo deslumbrante - XIII

    Directory of Open Access Journals (Sweden)

    Fernando Arbelaéz

    1965-05-01

    Full Text Available Es muy agradable tener en Atenas un amigo como Cayetano. Oigo mi propio idioma, y su música es una especie de anestesia muy suave para mis pensamientos. El mundo me parece grotesco, gesticulante y me produce miedo en algún lugar secreto de la mente. Escribo con una facilidad que me sorprende; pero ya se que esto no es más que el resultado de ese sutil mecanismo que reemplaza las pasiones para que podamos subsistir: el rojo de la lujuria va tomando los dorados colores del orgullo con el repique de la máquina. No creo que haya escrito con tanta fluidez y por tan largo tiempo. Es evidente, el ejercicio de teclear descansa los nervios y la concentración descansa el espíritu, así estemos meditando en nuestras propias miserias.

  1. Contact stress by the method of finite elements of the steel AISI 1045 hardened by roller; Tensiones de contacto por el metodo de elementos finitos del acero AISI 1045 endurecido por rodillo

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-columbie, T.; Rodriguez-Gonzalez, I.; Alcantara-Borges, D.; Fernandez-Guilarte, E.

    2012-11-01

    In this paper, the tense-deformational behavior is analyzed by means of simulation using the finite element method for AISI 1045 cold rolled deformed steel. ANYSYS V.10 software was used in this study. Revolution number, compressive strength and tool feed rate were the variables considered in the deformation process. They allowed determining the contact stress of the deformed material. The material used was 30 mm diameter and 100 mm length. Samples of 30 mm diameter and 3 mm thickness were prepared for the optical microscopic observation, which were compared to the results obtained from the simulation. The tensile status of the deformed samples was evaluated as from the reduction of the average size of the grains as per the strength applied. This study intends to show that the cold hardening method is a surface hardening option. (Author)

  2. EL ENTORNO INTERNACIONAL

    Directory of Open Access Journals (Sweden)

    Alberto Romero

    2000-05-01

    Full Text Available La división internacional del trabajo experimentó cambios trascendentales en su estructura durante el siglo XX, jalonados por impresionantes avances tecnológicos durante las décadas que siguieron a la segunda guerra mundial. El mapa político surgido de la conflagración mundial condujo a la conformación de dos campos antagónicos: el socialista y el capitalista, los cuales ejercieron gran influencia en el avance del conocimiento. Con el derrumbe del sistema socialista la economía de mercado salió fortalecida, intensificándose el proceso de globalización a nivel planetario, sin que ello condujese a disminuir la brecha entre un pequeño grupo de potencias tecnológicamente desarrolladas y la mayoría de países del mundo. En este sentido, el entorno internacional sigue caracterizándose por la participación desigual de los diferentes grupos de países en los principales indicadores de la economía mundial, especialmente en aquellos relacionados con las tecnologías de punta, lo cual ha impedido disminuir el atraso socioeconómico en los llamados países en desarrollo. Igualmente, el modelo consumista adoptado por las naciones desarrolladas ha dado como resultado el creciente deterioro del medio ambiente y el agotamiento de los recursos naturales, poniendo en peligro la calidad de vida de las futuras generaciones.

  3. Estresse no cotidiano acadêmico: o olhar dos alunos de Enfermagem da Universidade Federal do Piauí Estrés en el cotidiano académico: la visión de los estudiantes de enfermería de la Universidad Federal del Piauí - Brasil Stress in the academic daily: a nursing student view from the Federal University of Piauí - Brazil

    Directory of Open Access Journals (Sweden)

    Claudete Ferreira de Souza Monteiro

    2007-03-01

    situaciones de estrés repercuten de forma negativa en el desempeño de las actividades académicas desarrolladas por alumnos.This study aimed at know stress' situations lived by graduate students of nursing from Federal University of Piauí (UFPI in the academic scope. The methodology consisted of an exploratory study, qualitative, with data collection through semistructured interview applied to 22 students. The results made possible the construction of categories of analysis: stressor situations, stress symptoms and the development of academic activities. It has been verified that stress situations are present during the course, with relevance in certain moments, such as the ingression in the university, the attending pharmacology course for nursing and irregular weekly course load in specific periods of the course. It was evidenced that the symptoms presented by the students was of physiological and emotional aspects. At last, was concluded that stress situations have a negative influence upon the development of academic activities developed by students.

  4. O estresse e a enfermagem: a percepção das auxiliares de enfermagem de uma instituição pública El estrés y la enfermería: la percepción de auxiliares de enfermería de una institución publica Stress and nursing: the nursing's auxiliaries perception of a public institution

    Directory of Open Access Journals (Sweden)

    Thelma Spindola

    2007-06-01

    Full Text Available Estudo descritivo em abordagem qualitativa que teve como objetivo identificar como as auxiliares de enfermagem relacionam o estresse às suas atividades diárias. Foram investigadas 15 trabalhadoras de um hospital público no município do Rio de Janeiro. A análise temática dos resultados evidenciou que o estresse é percebido como um distúrbio emocional que acarreta desequilíbrio da saúde mental, ocasionando irritação, mau humor e incapacidade para o trabalho. Não se julgam estressadas, embora algumas refiram esta sensação em certas ocasiões. Acreditam que a atividade laboral pode contribuir para o estresse pelas condições e características do trabalho que realizam. Podemos concluir que embora definam o estresse como um distúrbio e atuem em condições desfavoráveis, nem todas percebem a influência destes fatores no seu equilíbrio emocional, sendo importante que se valorize a saúde mental dos trabalhadores, especialmente os profissionais de enfermagem, que necessitam estar bem física e mentalmente para interagirem com a clientela auxiliando-os.Estudio descriptivo, con abordaje cualitativo, que tuvo como objeto identificar como las auxiliares de enfermería relacionan el estrés a sus actividades diarias. Fueron investigadas 15 trabajadoras de un hospital público del municipio de Rio de Janeiro. El análisis temático de los resultados reveló que el estrés es percibido como un disturbio emocional que causa un desequilibrio en la salud mental, provocando irritación, mal humor, e incapacidad para el trabajo. Estas profesionales no se consideran estresadas, aunque algunas mencionen estas sensaciones en ciertas ocasiones. Ellas creen que la actividad laboral puede contribuir para el estrés, debido a las condiciones y características del trabajo que realizan. Podemos concluir aunque definan el estrés como un disturbio y actúen en condiciones desfavorables, no son todas las que perciben la influencia de estos factores en su

  5. Distinguishing modified gravity models

    International Nuclear Information System (INIS)

    Brax, Philippe; Davis, Anne-Christine

    2015-01-01

    Modified gravity models with screening in local environments appear in three different guises: chameleon, K-mouflage and Vainshtein mechanisms. We propose to look for differences between these classes of models by considering cosmological observations at low redshift. In particular, we analyse the redshift dependence of the fine structure constant and the proton to electron mass ratio in each of these scenarios. When the absorption lines belong to unscreened regions of space such as dwarf galaxies, a time variation would be present for chameleons. For both K-mouflage and Vainshtein mechanisms, the cosmological time variation of the scalar field is not suppressed in both unscreened and screened environments, therefore enhancing the variation of constants and their detection prospect. We also consider the time variation of the redshift of distant objects using their spectrocopic velocities. We find that models of the K-mouflage and Vainshtein types have very different spectroscopic velocities as a function of redshift and that their differences with the Λ-CDM template should be within reach of the future ELT-HIRES observations

  6. MODIFIED GYPSUM BINDER

    Directory of Open Access Journals (Sweden)

    KONDRATEVA N. V.

    2017-02-01

    Full Text Available Summary. Statement of the problem. A disadvantage of the gypsum binder is the limited water resistance of products that historically led to the use of gypsum products mostly for internal construction and finishing works. To regulate the process of hydration and structure formation of the use of chemical additives that are introduced with the mixing water or in the production of the binder. As a rule, substances that increase the solubility of the gypsum binder referred to as the hardening accelerator, and substances which retard the solubility of the inhibitors of hardening of the mixture. Most accelerators and retarders hardening affect adversely on the final strength of the mixture. More effective impact on gypsum binder additives have plasticizers. The purpose of the article. Getting gypsum binder modified with the aim of improving its water resistance and improvement of some technological factors (the time of hardening, water gypsum ratio, etc. would reduce its shortcomings and expand the scope of application of the binder. Conclusion. The result of the research reviewed changes in the basic properties of the gypsum binder with the introduction of additives, plasticizers, and selected the most effective supplements to significantly reduce water gypsum ratio, to improve strength properties and to obtain gypsum binder more dense structure.

  7. Distinguishing modified gravity models

    Energy Technology Data Exchange (ETDEWEB)

    Brax, Philippe [Institut de Physique Théorique, Université Paris-Saclay, CEA, CNRS, F-91191 Gif/Yvette Cedex (France); Davis, Anne-Christine, E-mail: philippe.brax@cea.fr, E-mail: A.C.Davis@damtp.cam.ac.uk [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Cambridge, CB3 0WA (United Kingdom)

    2015-10-01

    Modified gravity models with screening in local environments appear in three different guises: chameleon, K-mouflage and Vainshtein mechanisms. We propose to look for differences between these classes of models by considering cosmological observations at low redshift. In particular, we analyse the redshift dependence of the fine structure constant and the proton to electron mass ratio in each of these scenarios. When the absorption lines belong to unscreened regions of space such as dwarf galaxies, a time variation would be present for chameleons. For both K-mouflage and Vainshtein mechanisms, the cosmological time variation of the scalar field is not suppressed in both unscreened and screened environments, therefore enhancing the variation of constants and their detection prospect. We also consider the time variation of the redshift of distant objects using their spectrocopic velocities. We find that models of the K-mouflage and Vainshtein types have very different spectroscopic velocities as a function of redshift and that their differences with the Λ-CDM template should be within reach of the future ELT-HIRES observations.

  8. El desarrollo del emprendedor

    OpenAIRE

    Arco Juan, Francisco Javier del

    2010-01-01

    En este trabajo pretendemos abordar el desarrollo de las competencias y de las cualidades del emprendedor. Para ello analizaremos como mediante el trabajo en equipo, el liderazgo y la toma de decisiones a la hora de elaborar un Plan de Negocio, el alumno desarrollo todas estas competencias básicas. Además, por supuesto, de la capacidad de emprender un negocio a través de las herramientas básicas para la puesta en marcha de un negocio. No data (2010) UEM

  9. El cartero siniestro

    Directory of Open Access Journals (Sweden)

    Christian Ferrer

    2015-01-01

    Full Text Available Temas centrales de este número son los medios, la ciencia y tercer milenio. Alude el autor que el periodismo y divulgación científica son actividades cada vez más importantes en un mundo tecnologizado y dependiente de la ciencia. El otro tema hace relación a la comunicación en el espacio urbano necesario de conocerlo no solo en la perspectiva de diagnóstico, sino también en la de proyección hacia una ciudad más humana y democrática.

  10. FELICIDAD EN EL TRABAJO

    OpenAIRE

    Salvatore Moccia

    2016-01-01

    Uno de los principales objetivos de la psicología del trabajo y de las organizaciones es promover tanto el bienestar como el rendimiento de los empleados. Sin embargo, los distintos autores nos son unánimes respectos a los fundamentos de la felicidad. El objetivo de este trabajo es presentar las enormes contribuciones de la Psicología Positiva y de la Filosofía al tema de la felicidad y sus influencias en el ámbito organizativo y de la productividad, ofreciendo una revisión de los distintos a...

  11. Viviendo el documental

    OpenAIRE

    Álvarez Moreno, Víctor

    2017-01-01

    En el siguiente trabajo se recoge el proceso de realización y elaboración de un documental en 360 grados sobre la catedral de Valladolid bajo el título Reconstruyendo la catedral. El trabajo une realidad virtual con narrativa periodística. La realidad virtual es una herramienta que permite transformar al espectador en un testigo de la historia. En este caso, se muestra lo que pudo ser la catedral de Valladolid, cuyo objetivo era convertirse en la catedral más grande del territorio europeo. ...

  12. El futuro... Hoy

    Directory of Open Access Journals (Sweden)

    Luis Carlos Vargas

    2015-05-01

    Full Text Available RESUMEN El desarrollo tecnológico en el campo de la microelectrónica y los computadores de los últimos 8 años, equivale comparativamente al acumulado de los últimos  80 años del desarrollo de la electrónica. Estos desarrollos están generando en el mundo un jalonamiento importante de nuevas aplicaciones y requerimientos de investigación indispensables para entender el sinnúmero de oportunidades en aplicaciones derivadas de estos desarrollos.

  13. Fatigue life estimation of welded components considering welding residual stress relaxation and its mean stress effect

    International Nuclear Information System (INIS)

    Han, Seung Ho; Han, Jeong Woo; Shin, Byung Chun; Kim, Jae Hoon

    2003-01-01

    The fatigue life of welded joints is sensitive to welding residual stress and complexity of their geometric shapes. To predict the fatigue life more reasonably, the effects of welding residual stress and its relaxation on their fatigue strengths should be considered quantitatively, which are often regarded to be equivalent to the effects of mean stresses by external loads. The hot-spot stress concept should be also adopted which can reduce the dependence of fatigue strengths for various welding details. Considering the factors mentioned above, a fatigue life prediction model using the modified Goodman's diagram was proposed. In this model, an equivalent stress was introduced which is composed of the mean stress based on the hot-spot stress concept and the relaxed welding residual stress. From the verification of the proposed model to real welding details, it is proved that this model can be applied to predict reasonably their fatigue lives

  14. Fatigue life estimation considering welding residual stress and hot-spot stress of welded components

    International Nuclear Information System (INIS)

    Han, S. H.; Lee, T. K.; Shin, B. C.

    2002-01-01

    The fatigue life of welded joints is sensitive to welding residual stress and complexity of their geometric shapes. To predict the fatigue life more reasonably, the effects of welding residual stress and its relaxation have to be considered quantitatively which are equivalent to mean stress by external loads. The hot-spot stress concept should be also adopted which can be reduce the dependence of fatigue strengths for various welding details. Considering the factors mentioned above, a fatigue life prediction model using the modified Goodman's diagram was proposed. In this model, an equivalent stress was introduced which are composed of the mean stress based on the hot-spot stress concept and the relaxed welding residual stress. From the verification of the proposed model to real welding details, it is confirmed that this model can be applied to predict reasonably their fatigue lives

  15. Shifted-modified Chebyshev filters

    OpenAIRE

    ŞENGÜL, Metin

    2013-01-01

    This paper introduces a new type of filter approximation method that utilizes shifted-modified Chebyshev filters. Construction of the new filters involves the use of shifted-modified Chebyshev polynomials that are formed using the roots of conventional Chebyshev polynomials. The study also includes 2 tables containing the shifted-modified Chebyshev polynomials and the normalized element values for the low-pass prototype filters up to degree 6. The transducer power gain, group dela...

  16. Stress Management

    Science.gov (United States)

    ... with regions of your brain that control mood, motivation and fear. The body's stress-response system is ... problems Headaches Heart disease Sleep problems Weight gain Memory and concentration impairment That's why it's so important ...

  17. Stressing academia?

    DEFF Research Database (Denmark)

    Opstrup, Niels; Pihl-Thingvad, Signe

    Incongruences between the individual and the organizational work context are potential stressors. The present study focuses on the relationship between a complementary need-supply fit and Danish researchers’ self-perceived job stress. Strain is expected to increase as organizational supplies fall...... hand, the fit on “hard” dimensions as salary, financial rewards and career opportunities is found to be unrelated to the researchers’ self-perceived stress-level. The fit with regard to job security is an important exception, however....... to “soft” dimensions as freedom and independence in the job, personal and professional development at work, and receiving peer recognition is highly significant for the researchers’ self-perceived stress-level. The better the fit is the lower stress-levels the researchers’ on average report. On the other...

  18. El papel del Estado en el microfinanciamiento

    Directory of Open Access Journals (Sweden)

    Celia Hernández Cortés

    2015-01-01

    Full Text Available La intervención del Estado tradicionalmente se ha justificado al afirmar que: “el propósito de toda intervención es mejorar el nivel de bienestar de la sociedad y, en el caso de la intervención en los mercados financieros, ese objetivo adopta la forma de aseguramiento de solvencia y eficiencia del sistema” (Martínez, 2002: 747. Más allá de las limitaciones y críticas que sostenemos en este artículo respecto a la viabilidad de este instrumento de política pública, para incidir sobre los factores estructurales determinantes de la pobreza, que lamentablemente se generaliza y profundiza en la modalidad neoliberal del capitalismo, el propósito de este trabajo es atender los problemas surgidos en el funcionamiento general de las microfinanzas y la necesaria intervención gubernamental, para asegurar la solvencia de las instituciones y la protección de la población usuaria de este tipo de servicios financieros. Se trata, entonces, de una reflexión colectiva de un conjunto de acciones de microfinanciamiento llevadas a cabo en México y en otros países, que podemos denominar complementarias del mercado financiero formal.

  19. 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

  20. Stress fractures

    International Nuclear Information System (INIS)

    Berquist, T.H.; Cooper, K.L.; Pritchard, D.J.

    1985-01-01

    The diagnosis of a stress fracture should be considered in patients presented with pain after a change in activity, especially if the activity is strenuous and the pain is in the lower extremities. Since evidence of the stress fracture may not be apparent for weeks on routine radiographs, proper use of other imaging techniques will allow an earlier diagnosis. Prompt diagnosis is especially important in the femur, where displacement may occur

  1. Avaliação de diferentes híbridos suínos submetidos à insensibilização elétrica e gasosa (CO2. Parte 1: mensuração de indicadores sanguíneos de estresse Evaluation of pig hybrids stunned with electrical and gaseous (co2 systems. Part 1: blood stress indicators

    Directory of Open Access Journals (Sweden)

    William Bertoloni

    2006-09-01

    Full Text Available Suínos provenientes de três linhagens genéticas A, B e C comercializadas no Brasil, com peso vivo de 100 a 120 kg foram submetidos ao insensibilizador elétrico manual (Karl Schermer 220-230/250 volts, 45-60 Hz e 1,4 -1,5 A e ao sistema gasoso coletivo (COMBI-BUTINA 90% CO2. Alíquotas sanguíneas, para determinação dos níveis de creatina fosfoquinase (CPK, lactato e cortisol, assim como amostras do músculo semimembranosus (10 g para a determinação do gene halotano, foram coletadas. Comparando-se os sistemas de insensibilização elétrico e gasoso (CO2, o elétrico demonstrou ser mais estressante, proporcionando maiores concentrações plasmáticas de cortisol (p Pigs of three genetics lineages A, B and C marketed in Brazil, with alive weight from 100 to 120 kg were submitted to the manual electric stunning (Karl Schermer 220-230/250 volts, 45-60 Hz and 1.4 -1.5 A and to the collective gaseous system (COMBI-BUTINA 90% CO2. Blood samples, for levels determination of creatine phosphokinase (CPK, lactate and cortisol, as well as samples of the semimembranosus muscle (10 g for the determination of the gene halothane, were collected. Being compared the electric and gaseous stunning systems, the electric stunning did demonstrate to be more stressful providing larger plasmatic concentrations of cortisol ( p < 0.001 and lactate ( p < 0.001 for the genetic lineages A and C, in the studied conditions.However it didn't observe significant differences beween the sanguine indicators and stunning systems in subject when the lineage B was considered. Significant differences among the genetic lineages A, B and C were obtained being compared the plasmatic values of creatine phosphokinase (p < 0.001, lactate (p < 0.001 and cortisol (p < 0.001 when stunned with the gaseous system, however when the electric system was used only the cortisol values presented significant differences (p < 0.001. The presence of the gene halothane (Nn was only observed in the

  2. Concept Analysis: Alzheimer's Caregiver Stress.

    Science.gov (United States)

    Llanque, Sarah; Savage, Lynette; Rosenburg, Neal; Caserta, Michael

    2016-01-01

    The aim of this article was to analyze the concept of caregiver stress in the context of caring for a person with Alzheimer's disease and related dementias. Currently, there are more than 15 million unpaid caregivers for persons suffering from Alzheimer's disease and related dementias. This unpaid care can be stressful for caregivers due to the chronic nature of the disease process, as well as other factors. The paper incorporates the modified method of Wilson's concept analysis procedure to analyze the concept of caregiver stress. A review of the literature was undertaken using the Cumulative Index to Nursing and Allied Health Literature, Google Scholar, and PubMed. A theoretical definition of caregiver stress is provided, and the defining attributes, related concepts, antecedents, and consequences of caregiver stress are proposed, and case studies are presented. The analysis demonstrates that caregiver stress is the unequal exchange of assistance among people who stand in close relationship to one another, which results in emotional and physical stress on the caregiver. Implications for future nursing research and practice conclude the paper. © 2014 Wiley Periodicals, Inc.

  3. Algunas consideraciones sobre el efecto del espesor de llanta en la resistencia a la fractura de ruedas dentadas.

    Directory of Open Access Journals (Sweden)

    G. González Rey

    2009-01-01

    Full Text Available En transmisiones por engranajes, con ruedas de llantas delgadas trabajando en régimen de carga nominal y con suficiente resistencia a los esfuerzos de flexión en la raíz de los dientes, ha sido observado el surgimiento de grietas por debajo de los dientes que se propagan a través de la llanta con rotura por fractura de la rueda dentada [2]. Las actuales formulaciones de las Normas ISO y AGMA para valorar el esfuerzo máximo resultante en la base de los dientes de las ruedas de engranajes cilíndricos introducen factores modificadores de los esfuerzos (YB y KB para ruedas dentadas con llantas de pequeño espesor. Estudios realizados [3, 13, 14, 15, 16, 17] valoran de forma diferente el factor por adelgazamiento de llanta en dependencia de la geometría de las ruedas y la rigidez conjunta entre llanta y los nervios soporte del núcleo de la rueda dentada. En el presente artículo, se expone un breve resumen del estado del arte sobre el tema, son mostrados y confirma dos resultados derivados de un análisis de la interrelación entre el factor por adelgazamiento de llanta, la razón de espesor relativo de la llanta y la razón de espesor relativo de los nervios del soporte en ruedas dentadas cilíndricas, y otros asociados con la tendencia del límite inferior de la razón de espesor relativo de la llanta en dependencia del número de dientes de la rueda.In thin rimmed gears running with nominal load and sufficient bending stress resistance at the tooth-root, fatigue cracks with propagation through the rims, rather than at the tooth fillet, has been observed [2]. Both the ISO and AGMA standards introduce stress-modifying factors (denominated rim thickness factors YB and KB for the bending stress calculation where the rim thickness is not sufficient to provide full support of the tooth root. However, some different behavior of rim thickness factor depending on gear geometry and the stiffness of both rim and web thickness have been reported [3

  4. Implications of stress range for inelastic analysis

    International Nuclear Information System (INIS)

    Karabin, M.E.; Dhalla, A.K.

    1981-01-01

    The elastic stress range over a complete load cycle is routinely used to formulate simplified rules regarding the inelastic behavior of structures operating at elevated temperature. For example, a 300 series stainless steel structure operating at elevated temperature, in all probability, would satisfy the ASME Boiler and Pressure Vessel Code criteria if the linearized elastic stress range is less than three times the material yield strength. However, at higher elastic stress ranges it is difficult to judge, a priori, that a structural component would comply with inelastic Code criteria after a detailed inelastic analysis. The purpose of this paper is to illustrate that it is not the elastic stress range but the stress intensities at specific times during a thermal transient which provide a better insight into the inelastic response of the structure. The specific example of the CRBRP flued head design demonstrates that the temperature differential between various parts of the structure can be changed by modifying the insulation pattern and heat flow path in the structure, without significantly altering the elastic stress range over a complete load cycle. However, the modified design did reduce the stress intensity during steady state elevated temperature operation. This modified design satisfied the inelastic Code criteria whereas the initial design failed to comply with the strain accumulation criterion

  5. El error en el delito imprudente

    Directory of Open Access Journals (Sweden)

    Miguel Angel Muñoz García

    2011-12-01

    Full Text Available La teoría del error en los delitos culposos constituye un tema álgido de tratar, y controversial en la dogmática penal: existen en realidad muy escasas referencias, y no se ha llegado a un consenso razonable. Partiendo del análisis de la estructura dogmática del delito imprudente, en donde se destaca el deber objetivo de cuidado como elemento del tipo sobre el que recae el error, y de las diferentes posiciones doctrinales que defienden la aplicabilidad del error de tipo y del error de prohibición, se plantea la viabilidad de este último, con fundamento en razones dogmáticas y de política criminal, siendo la infracción del deber objetivo de cuidado en tanto consecuencia del error, un tema por analizar en sede de culpabilidad.

  6. El enfoque digital en el aula

    Directory of Open Access Journals (Sweden)

    Paula Cancelas Álvarez

    2012-08-01

    Full Text Available Con la revolución tecnológica de la época en la que vivimos, que está llegandotambién al mundo de ELE, todos sabemos que es solo cuestión de tiempo que en todaslas aulas haya pizarras digitales interactivas. Esto implica que, si bien hasta ahorapodíamos elegir si queríamos utilizar en el aula las nuevas tecnologías o no, a partir delmomento en el que instalen en nuestras aulas las pizarras digitales no vamos a tenerelección y, lo que es más importante, no vamos a tener ninguna buena excusa para noutilizar las nuevas tecnologías. Por esta razón, es necesario concienciarse y estarpreparado para poder sacarle el mayor rendimiento en las clases.

  7. Thermal stress effects in intermetallic matrix composites

    Science.gov (United States)

    Wright, P. K.; Sensmeier, M. D.; Kupperman, D. S.; Wadley, H. N. G.

    1993-01-01

    Intermetallic matrix composites develop residual stresses from the large thermal expansion mismatch (delta-alpha) between the fibers and matrix. This work was undertaken to: establish improved techniques to measure these thermal stresses in IMC's; determine residual stresses in a variety of IMC systems by experiments and modeling; and, determine the effect of residual stresses on selected mechanical properties of an IMC. X ray diffraction (XRD), neutron diffraction (ND), synchrotron XRD (SXRD), and ultrasonics (US) techniques for measuring thermal stresses in IMC were examined and ND was selected as the most promising technique. ND was demonstrated on a variety of IMC systems encompassing Ti- and Ni-base matrices, SiC, W, and Al2O3 fibers, and different fiber fractions (Vf). Experimental results on these systems agreed with predictions of a concentric cylinder model. In SiC/Ti-base systems, little yielding was found and stresses were controlled primarily by delta-alpha and Vf. In Ni-base matrix systems, yield strength of the matrix and Vf controlled stress levels. The longitudinal residual stresses in SCS-6/Ti-24Al-llNb composite were modified by thermomechanical processing. Increasing residual stress decreased ultimate tensile strength in agreement with model predictions. Fiber pushout strength showed an unexpected inverse correlation with residual stress. In-plane shear yield strength showed no dependence on residual stress. Higher levels of residual tension led to higher fatigue crack growth rates, as suggested by matrix mean stress effects.

  8. El cuerpo, el gueto y el Estado penal

    Directory of Open Access Journals (Sweden)

    Loïc Wacquant

    2010-02-01

    Full Text Available

    Este artículo analiza el enfoque del autor sobre la etnografía, la teoría social, y la

  9. Stress vulnerability and the effects of moderate daily stress on sleep polysomnography and subjective sleepiness.

    Science.gov (United States)

    Petersen, Helena; Kecklund, Göran; D'Onofrio, Paolo; Nilsson, Jens; Åkerstedt, Torbjörn

    2013-02-01

    The purpose of this study was to investigate if and how sleep physiology is affected by naturally occurring high work stress and identify individual differences in the response of sleep to stress. Probable upcoming stress levels were estimated through weekly web questionnaire ratings. Based on the modified FIRST-scale (Ford insomnia response to stress) participants were grouped into high (n = 9) or low (n = 19) sensitivity to stress related sleep disturbances (Drake et al., 2004). Sleep was recorded in 28 teachers with polysomnography, sleep diaries and actigraphs during one high stress and one low stress condition in the participants home. EEG showed a decrease in sleep efficiency during the high stress condition. Significant interactions between group and condition were seen for REM sleep, arousals and stage transitions. The sensitive group had an increase in arousals and stage transitions during the high stress condition and a decrease in REM, whereas the opposite was seen in the resilient group. Diary ratings during the high stress condition showed higher bedtime stress and lower ratings on the awakening index (insufficient sleep and difficulties awakening). Ratings also showed lower cognitive function and preoccupation with work thoughts in the evening. KSS ratings of sleepiness increased during stress for the sensitive group. Saliva samples of cortisol showed no effect of stress. It was concluded that moderate daily stress is associated with a moderate negative effect on sleep sleep efficiency and fragmentation. A slightly stronger effect was seen in the sensitive group. © 2012 European Sleep Research Society.

  10. El cuento: Marcelo y el fantasma

    Directory of Open Access Journals (Sweden)

    Néstor Madrid Malo

    1966-01-01

    Full Text Available Al lado de su madre, que manejaba velozmente el rojo Alfa Romeo, Marcelo sentía ese grato sabor que el obtenido triunfo o los realizados deseos dejaban siempre en su paladar. Así como este, en su gustativa confabulación con la lengua, le proporcionaba dulces del icias o amargos suplicios -según fueran estimulados por un exquisito postre o por un detestable remedio- así también sus estados de ánimo se trasuntaban en su boca en forma de sabores, que él había aprendido a conocer por la densidad de la saliva.

  11. EL TEATRO EN EL AULA DE IDIOMAS

    OpenAIRE

    Calvo-Valero, Eduardo

    2013-01-01

    La siguiente propuesta de intervención se dirige a impulsar la adquisición del inglés como segunda lengua desde el Primer Ciclo de Primaria ya que en la sociedad actual es muy demandada. Son muy variadas las metodologías y recursos que se dirigen a la enseñanza de idiomas. En este trabajo fin de grado hemos mostrado el teatro como recurso educativo que dispone de elementos que favorecen la transmisión de conocimientos. Por ello, hemos analizado algunas técnicas teatrales así como las capac...

  12. El cine posmoderno

    Directory of Open Access Journals (Sweden)

    Edel Cadena Vargas

    2015-05-01

    Full Text Available En el presente trabajo se trata de dar respuesta a las siguientes preguntas: ¿cuál es el origen del cine posmoderno?, ¿cuáles son los factores que permiten su creación?, ¿a qué sentimiento responde?

  13. Keynes y el empleo

    Directory of Open Access Journals (Sweden)

    Héctor Ruiz Ramírez

    2013-01-01

    Full Text Available Keynes, al igual que Marx y la escuela ortodoxa (clásica y neoclásica, supone libre concurrencia en el mercado de productos, pero a diferencia de todos ellos, asume un mercado de trabajo imperfecto, en el cual los salarios se negocian en términos nominales y no reales, evidenciando así un desempleo involuntario. Igualmente, Keynes postula una rigidez en el mercado de capitales que limita la expansión del empleo, no solo en el corto plazo, sino también en el largo plazo, aun cuando el beneficio sea todavía positivo. Mientras los clásicos sostenían la idea de precios y salarios flexibles, Keynes señalaba lo contrario, es decir, rígidos e inflexibles. Para Keynes, la causa del desempleo era la insuficiente demanda agregada y que el desempleo no se corregía con una reducción de salarios, sino con una mayor demanda. Este fue su postulado básico para explicar el empleo.

  14. Cuba en el PIDC

    Directory of Open Access Journals (Sweden)

    Enrique González Manet

    2015-01-01

    Full Text Available Intervención de Enrique González Manet, delegado cubano, en la II Reunión del Consejo del Programa Internacional para el Desarrollo de las Comunicaciones -PIDC-en la ciudad de Acapulco, México, el 19 de enero de 1981

  15. El sistema constructivo

    OpenAIRE

    Leser S., Heinz; Gómez Lerou, Luis; Salomone R., Vanessa

    2003-01-01

    Se describe el sistema constructivo de entramado en madera, “plataforma” (platform frame) utilizado preferentemente en las construcciones de varios pisos en el campamento minero de Sewell, Chile./The following is a description of the platform frame used in several stories buildings in the mining settlement Sewell, in Chile.

  16. El sistema constructivo

    Directory of Open Access Journals (Sweden)

    Leser S., Heinz

    2003-06-01

    Full Text Available Se describe el sistema constructivo de entramado en madera, “plataforma” (platform frame utilizado preferentemente en las construcciones de varios pisos en el campamento minero de Sewell, Chile./The following is a description of the platform frame used in several stories buildings in the mining settlement Sewell, in Chile.

  17. El placer traidor

    OpenAIRE

    García, Luis Eduardo

    2014-01-01

    Un apasionado es el poseído por alguna pasión o afecto. Y Un apasionado del periodismo es el que padece en carne propia esa enfermedad que mata, por lo general, con ataques al corazón, hipertensión o ansiedad.

  18. El IDRC en Colombia

    International Development Research Centre (IDRC) Digital Library (Canada)

    gación de Colombia en salud, agri- ... y desarrollar una base nacional de datos ... apoyada por el IDRC mostró caminos para .... conocimiento con los formuladores de políticas, con otros investigadores y comunidades en todo el mundo.

  19. El museo deslumbrante - IX

    Directory of Open Access Journals (Sweden)

    Fernando Arbeláez

    1964-12-01

    Full Text Available El punto de partida y el punto de llegada de todas mis actividades en Atenas es la plaza Síntagma, la plaza de la Constitución, con sus grandes cafeterías y bares al aire libre y enmarcada por modernas edificaciones.

  20. El protagonismo juvenil

    Directory of Open Access Journals (Sweden)

    COLJUVENTUD

    1996-01-01

    Full Text Available El objeto de este documento de trabajo, más que contestar a las preguntas formuladas, es intentar una reflexión sobre ellas situando las preocupaciones que les subyacen en el intento de delinear uno de los acercamientos posibles a la construcción de las respuestas.

  1. Horseshoes in modified Chen's attractors

    International Nuclear Information System (INIS)

    Huang Yan; Yang Xiaosong

    2005-01-01

    In this paper we study dynamics of a class of modified Chen's attractors, we show that these attractors are chaotic by giving a rigorous verification for existence of horseshoes in these systems. We prove that the Poincare maps derived from these modified Chen's attractors are semi-conjugate to the 2-shift map

  2. Surface-modified electrodes (SME)

    NARCIS (Netherlands)

    Schreurs, J.P.G.M.; Barendrecht, E.

    1984-01-01

    This review deals with the literature (covered up to August 1983), the characterization and the applications of Surface-Modified Electrodes (SME). As a special class of SME's, the Enzyme-Modified Electrode (EME) is introduced. Three types of modification procedures are distinguished; i.e. covalent

  3. Genetically modified foods and allergy.

    Science.gov (United States)

    Lee, T H; Ho, H K; Leung, T F

    2017-06-01

    2015 marked the 25th anniversary of the commercial use and availability of genetically modified crops. The area of planted biotech crops cultivated globally occupies a cumulative two billion hectares, equivalent to twice the land size of China or the United States. Foods derived from genetically modified plants are widely consumed in many countries and genetically modified soybean protein is extensively used in processed foods throughout the industrialised countries. Genetically modified food technology offers a possible solution to meet current and future challenges in food and medicine. Yet there is a strong undercurrent of anxiety that genetically modified foods are unsafe for human consumption, sometimes fuelled by criticisms based on little or no firm evidence. This has resulted in some countries turning away food destined for famine relief because of the perceived health risks of genetically modified foods. The major concerns include their possible allergenicity and toxicity despite the vigorous testing of genetically modified foods prior to marketing approval. It is imperative that scientists engage the public in a constructive evidence-based dialogue to address these concerns. At the same time, improved validated ways to test the safety of new foods should be developed. A post-launch strategy should be established routinely to allay concerns. Mandatory labelling of genetically modified ingredients should be adopted for the sake of transparency. Such ingredient listing and information facilitate tracing and recall if required.

  4. Modified General Relativity and Cosmology

    Science.gov (United States)

    Abdel-Rahman, A.-M. M.

    1997-10-01

    Aspects of the modified general relativity theory of Rastall, Al-Rawaf and Taha are discussed in both the radiation- and matter-dominated flat cosmological models. A nucleosynthesis constraint on the theory's free parameter is obtained and the implication for the age of the Universe is discussed. The consistency of the modified matter- dominated model with the neoclassical cosmological tests is demonstrated.

  5. Chronic early life stress induced by limited bedding and nesting (LBN) material in rodents: critical considerations of methodology, outcomes and translational potential.

    Science.gov (United States)

    Walker, Claire-Dominique; Bath, Kevin G; Joels, Marian; Korosi, Aniko; Larauche, Muriel; Lucassen, Paul J; Morris, Margaret J; Raineki, Charlis; Roth, Tania L; Sullivan, Regina M; Taché, Yvette; Baram, Tallie Z

    2017-09-01

    The immediate and long-term effects of exposure to early life stress (ELS) have been documented in humans and animal models. Even relatively brief periods of stress during the first 10 days of life in rodents can impact later behavioral regulation and the vulnerability to develop adult pathologies, in particular an impairment of cognitive functions and neurogenesis, but also modified social, emotional, and conditioned fear responses. The development of preclinical models of ELS exposure allows the examination of mechanisms and testing of therapeutic approaches that are not possible in humans. Here, we describe limited bedding and nesting (LBN) procedures, with models that produce altered maternal behavior ranging from fragmentation of care to maltreatment of infants. The purpose of this paper is to discuss important issues related to the implementation of this chronic ELS procedure and to describe some of the most prominent endpoints and consequences, focusing on areas of convergence between laboratories. Effects on the hypothalamic-pituitary adrenal (HPA) axis, gut axis and metabolism are presented in addition to changes in cognitive and emotional functions. Interestingly, recent data have suggested a strong sex difference in some of the reported consequences of the LBN paradigm, with females being more resilient in general than males. As both the chronic and intermittent variants of the LBN procedure have profound consequences on the offspring with minimal external intervention from the investigator, this model is advantageous ecologically and has a large translational potential. In addition to the direct effect of ELS on neurodevelopmental outcomes, exposure to adverse early environments can also have intergenerational impacts on mental health and function in subsequent generation offspring. Thus, advancing our understanding of the effect of ELS on brain and behavioral development is of critical concern for the health and wellbeing of both the current

  6. El cuadro interactivo

    Directory of Open Access Journals (Sweden)

    Nuria del Río Blay

    2015-10-01

    Full Text Available Este artículo pretende animar el descubrimiento del potencial didáctico de una aplicación aparecida recientemente llamada Thinglink, utilizada para crear, de manera muy sencilla, imágenes interactivas en un periodo de tiempo sorprendentemente corto. Por todos es sabido que resulta conveniente explorar las infinitas posibilidades de integrar las TIC en el contexto educativo de E/LE puesto que incrementa la competencia digital necesaria para el estudiante hoy en día además de motivarle en el proceso de aprendizaje. En las líneas que siguen, se tratará de explicar el funcionamiento de esta herramienta web y después se ofrecerá un ejemplo de explotación didáctica con un grupo de estudiantes de E/LE universitarios.

  7. El eterno retorno

    Directory of Open Access Journals (Sweden)

    Gustavo Adolfo Calderón Vallejo

    2017-07-01

    Full Text Available La conversación que tuvieron el presidente de Colombia y el de Estados Unidos, al final de la visita del mes de mayo de este año, parecía un diálogo entre quienes no se escuchan. Mientras el presidente Santos recordaba que el problema de las drogas debe manejarse por todas las partes involucradas y en cooperación entre los países que son más exportadores y los que son más consumidores, el presidente de Estados Unidos le respondía que ese problema tendría una solución con la construcción del muro.

  8. DESBARATANDO EL LENGUAJE ESCOLAR

    Directory of Open Access Journals (Sweden)

    Silvia Duschatzky

    2017-03-01

    Full Text Available DOI: 10.12957/periferia.2016.27950El punto de vista escolar impide estar en los problemas. Pero la escuela habla en sus problemas, en lo ínfimo, en sus costados inentendibles para el universo representacional. Abandonar lenguaje y el punto de vista escolar; pensar el afuera, la presencia de lo no escolar; recuperar lo que allí hay de moviente, su textura sensible, el plano de lo desconocido. Pensar la escuela como efecto, y no como premisa. Abrir, a partir de la formulación de algunas proposiciones, umbrales de investigación que no devienen prescripción sino un proyecto que investiga de qué se trata lo comun y de qué lo educativo.

  9. Professional stress

    Directory of Open Access Journals (Sweden)

    Stanojević Dragana Z.

    2011-01-01

    Full Text Available Job stress is a line, for the person at work hired adverse physiological, psychological and behavioral reactions to situations in which job requirements are not in accordance with its capabilities, abilities and needs. Sources of stress at work are numerous. Personal factors: personality types have been most studied so far, environmental changes and demographic characteristics as well. Interpersonal stress inducing factors act and influence to the occurrence of many psychosomatic diseases. Psychosocial climate and relationships which are prevented or encouraged such as: cooperation and competition, trust and suspicion certainly affect to the appearance of professional stress. The way of leadership is very important. Organizational factors are the type of work, work time, noncompliance of the job, the introduction of new ethnologies, the conflict of personal roles, fear of job loss, bad physical conditions of working environment. The consequences of stress at work are numerous: at the cognitive level, the emotional level, the production plan, the health, plan reduces the immune system that cause a variety of psychosomatic illnesses and accidents at work.

  10. El precedente en Colombia

    Directory of Open Access Journals (Sweden)

    Carlos Bernal Pulido

    2008-01-01

    Full Text Available El objetivo de este informe es determinar si las sentencias judiciales tienen el carácter de precedente en el sistema jurídico colombiano, y si es así, cuál es el fundamento, cuáles las características y cuál el alcance de este carácter. En este contexto me referiré al precedente con las dos ideas que, de acuerdo con Bell, conforman este concepto, es decir: “tratar las decisiones previas como enunciados autoritativos del derecho que funcionan como buenas razones para decisiones subsecuentes” y exigir a los “jueces de tribunales específicos que consideren ciertas decisiones previas, sobre todo las de las altas cortes, como una razón vinculante”. Aquí defenderé la tesis según la cual, a pesar de que el derecho colombiano tiene la estructura y los fundamentos de un sistema de derecho continental, después de una evolución posterior a la Constitución de 1991, tanto el derecho positivo como la práctica han llegado a reconocer que las sentencias judiciales tienen el carácter de precedente. Presentaré los argumentos que sostienen esta tesis en dos partes. En la primera reconstruiré con brevedad el proceso que condujo al reconocimiento del carácter de precedente a la jurisprudencia y daré cuenta de los fundamentos jurídicos de tal carácter. En la segunda precisaré qué es precedente, cómo debe aplicarse y cuál es su alcance en el derecho colombiano.

  11. El puente de Brotonne sobre el Sena - Francia

    Directory of Open Access Journals (Sweden)

    Campenon, -

    1978-12-01

    Full Text Available This bridge solves the connection problem between Rouen and Le Havre. The need to preserve the maritime tradition of Rouen and to permit the heavy shipping traffic through the estuary forced a structural design which main part, 696.5 m long, consists of a 5-span triss-braced bridge. The central span, 320 m long, is the longest pre-stressed concrete span in the world. The structure also includes two access ramps. This article analyses the features and construction procedures of each element in the structure, namely: — Foundations, consisting on cylindrical piers for the main spans and piers on piles for the access ramps and viaducts. — The curved octagonal piles, creating an interesting aesthetical effect. — The deck consisting on a single monocelular girder, formed by twincore wedged, pieces, prestressed in all directions. — The tower with a constant 2.60 dimension crosswise and tapered from 4.80 to 2.84 meters lengthwise. — Tensors, prestressing, etc.

    Este puente resuelve el problema de comunicación entre Rouen y Le Havre. La necesidad de respetar la tradición marítima de Rouen y la navegación de barcos de gran tonelaje obligó a realizar una estructura cuya obra principal, de una longitud de 696,5 m, es un puente atirantado que tiene cinco tramos, de los cuales el central, de 320 m, constituye el récord del mundo de luz en hormigón pretensado. La estructura comprende, además, dos viaductos de acceso. En este artículo se hace un análisis de las características y procedimientos de construcción de cada uno de los elementos que componen la obra: — Las cimentaciones, que son columnas cilíndricas para las pilas principales, y sobre pilotes en las pilas de los viaductos de acceso. — Las pilas, de forma octogonal curvilínea, que producen un gran efecto estético. — El tablero es una viga monocelular, formada por dovelas de dos almas pretensadas en todas direcciones. — Las torres, cuya sección es

  12. El ayer, el hoy y el mañana

    Directory of Open Access Journals (Sweden)

    Corredor Pardo Katya Anyud

    1999-12-01

    Full Text Available

    Culturalmente, el anciano de hoy en nuestra sociedad, o en las grandes urbes, es considerado algunas veces por los jóvenes como un ser extraño y desagradable, como punto de partida de los  valores transmitidos en la familia los cuales deben ser revaluados y nosotros, los ancianos del mañana con los ancianos de hoy, cambiar de adentro hacia fuera. A su vez, evitar la transmisión generacional de estos valores a nuestros hijos realizando un análisis retrospectivo de la vida; cuando bebes, se tiene conciencia del uno al otro, y los niños en edad preescolar empiezan a conseguir compañeros, pero el grupo de amigos se fortalece a partir de los cinco o siete años, con frecuencia se escucha hablar con nostalgia de la vida en el colegio. Este lugar común es grato y feliz, adornado con carcajadas y anécdotas que despiertan e incentivan la imaginación y la realidad creada a partir del propio yo social, individual y cultural.

  13. The pile EL3; Pile EL3

    Energy Technology Data Exchange (ETDEWEB)

    Robert, J.; Raievski, V. [Commissariat a l' Energie Atomique, Paris (France). Centre d' Etudes Nucleaires; Hainzelin, J. [Chantiers de l' Atlantique (Penhoet-Loire), 75 - Paris (France)

    1959-07-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10{sup 14} n/cm{sup 2}/s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [French] Le programme de la pile laboratoire a haut flux EL3, a ete fixe en octobre 1954. C'est une pile moderee et refroidie a l'eau lourde. Les barres de combustible sont en uranium metal a 1,6 pour cent - 2 pour cent de molybdene, gainees a l'aluminium. Le flux thermique maximum dans le moderateur est de 10{sup 14} n/cm{sup 2}/s. Les etudes ont commence en janvier 1955, la construction en mai 1955, la premiere divergence a eu lieu en juillet 1957. On trouvera dans ce rapport, une description generale de la pile et de ses batiments annexes, l'etude physique de la pile et un certain nombre d'etudes technologiques executees pour la construction d'EL3. (auteur)

  14. The pile EL3; Pile EL3

    Energy Technology Data Exchange (ETDEWEB)

    Robert, J; Raievski, V [Commissariat a l' Energie Atomique, Paris (France). Centre d' Etudes Nucleaires; Hainzelin, J [Chantiers de l' Atlantique (Penhoet-Loire), 75 - Paris (France)

    1959-07-01

    The programme of the high flux laboratory pile EL3 was laid down in october 1954. It is a heavy-water moderated and cooled pile. The fuel rods are of uranium metal with 1.6 per cent - 2 per cent of molybdenum, with aluminium canning. The maximum thermal flux in the moderator is 10{sup 14} n/cm{sup 2}/s. Studies began in january 1955, construction in may 1955, and the first divergence took place in July 1957. This report gives a general description of the pile and its adjacent buildings, the physical study of the pile, and certain technological studies carried out for the construction of EL3. (author) [French] Le programme de la pile laboratoire a haut flux EL3, a ete fixe en octobre 1954. C'est une pile moderee et refroidie a l'eau lourde. Les barres de combustible sont en uranium metal a 1,6 pour cent - 2 pour cent de molybdene, gainees a l'aluminium. Le flux thermique maximum dans le moderateur est de 10{sup 14} n/cm{sup 2}/s. Les etudes ont commence en janvier 1955, la construction en mai 1955, la premiere divergence a eu lieu en juillet 1957. On trouvera dans ce rapport, une description generale de la pile et de ses batiments annexes, l'etude physique de la pile et un certain nombre d'etudes technologiques executees pour la construction d'EL3. (auteur)

  15. Modified Monkman–Grant relationship for austenitic stainless steel foils

    Energy Technology Data Exchange (ETDEWEB)

    Osman Ali, Hassan, E-mail: hassaninsan@gmail.com [Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia); Tamin, Mohd Nasir, E-mail: taminmn@fkm.utm.my [Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor (Malaysia)

    2013-02-15

    Characteristics of creep deformation for austenitic stainless steel foils are examined using the modified Monkman–Grant equation. A series of creep tests are conducted on AISI 347 steel foils at 700 °C and different stress levels ranging from 54 to 221 MPa. Results showed that at lower stress levels below 110 MPa, the creep life parameters ε{sub min},ε{sub r},t{sub r} can be expressed using the modified Monkman–Grant equation with exponent m′= 0.513. This indicates significant deviation of the creep behavior from the first order reaction kinetics theory for creep (m′ = 1.0). The true tertiary creep damage in AISI 347 steel foil begins after 65.9% of the creep life of the foil has elapsed at stress levels above 150 MPa. At this high stress levels, Monkman–Grant ductility factor λ{sup ′} saturates to a value of 1.3 with dislocation-controlled deformation mechanisms operating. At low stress levels, λ{sup ′} increases drastically (λ{sup ′}=190 at 54 MPa) when slow diffusion-controlled creep is dominant.

  16. El genoma humano

    Directory of Open Access Journals (Sweden)

    García Barreno, Pedro

    2002-01-01

    Full Text Available Not available

    El redescubrimiento de las leyes de Mendel sobre la herencia en las semanas que abrieron el siglo XX incitó una búsqueda científica para comprender la naturaleza y el contenido de la información genética que ha impulsado la biología durante los últimos cien años. El progreso científico conseguido se ha fraguado en cuatro fases que se corresponden, aproximadamente, con los cuatro cuartos del siglo XX. El primero estableció las bases celulares de la herencia: los cromosomas. El segundo definió las bases moleculares de la herencia: la doble hélice de ADN. El tercero descifró las bases informativas de la herencia con el descubrimiento de los mecanismos biológicos mediante los que la célula lee la información codificada en los genes; luego, con la invención de la tecnología del ADN recombinante de clonajey de secuenciación, los científicos pudieron hacer lo mismo. El último cuarto del siglo estuvo marcado por un lento pero constante esfuerzo para descifrar genes primero y, por fin, genomas enteros que han propiciado el desarrollo de la genómica. El día 26 de junio de 2000 se hacía público un «borrador de trabajo» de la secuencia del genoma humano. Las revistas Nature (vol 409, n.º 6822 y Science (vol 291, n.º 5507 dedicaban números especiales a la publicación de la secuencia en el mes de febrero de 2001 (el día 15 Nature y, al día siguiente, Science. «La humanidad ha recibido un gran regalo. La conclusión de la secuencia del genoma humano ofrece una herramienta poderosa para descifrar los secretos de nuestra herencia genética y para precisar nuestro lugar entre otros participantes en la aventura de la vida».

  17. Stress Analysis

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    The following types of forces contribute to the stresses in a Dolos in a pack exposed to waves: 1)Gravity forces Compaction forces (mainly due to settlements, gravity and flow forces) 2) Flow forces 3) Impact forces (impacts between moving concrete blocks)......The following types of forces contribute to the stresses in a Dolos in a pack exposed to waves: 1)Gravity forces Compaction forces (mainly due to settlements, gravity and flow forces) 2) Flow forces 3) Impact forces (impacts between moving concrete blocks)...

  18. Welding stresses

    International Nuclear Information System (INIS)

    Poirier, J.; Barbe, B.; Jolly, N.

    1976-01-01

    The aim is to show how internal stresses are generated and to fix the orders of magnitude. A realistic case, the vertical welding of thick plates free to move one against the other, is described and the deformations and stresses are analyzed. The mathematical model UEDA, which accounts for the elastic modulus, the yield strength and the expansion coefficient of the metal with temperature, is presented. The hypotheses and results given apply only to the instantaneous welding of a welded plate and to a plate welded by a moving electrode [fr

  19. Workplace stress: what is the role of positive mental health?

    Science.gov (United States)

    Page, Kathryn M; Milner, Allison J; Martin, Angela; Turrell, Gavin; Giles-Corti, Billie; LaMontagne, Anthony D

    2014-08-01

    To examine whether positive mental health (PMH)-a positively focused well-being construct-moderates the job stress-distress relationship. Longitudinal regression was used to test two waves of matched, population-level data from a sample of older, working Australian adults (n = 3291) to see whether PMH modified the relationship between work stress and later psychological distress. Time 1 work stress was positively associated with distress at both time points. Positive mental health was negatively associated with work stress at both time points. Positive mental health modified the impact of work stress on psychological distress. This effect only occurred for those with the highest levels of PMH. Positive mental health may help protect workers from the effect of workplace stress but only in a small proportion of the population. Therefore, to improve workplace mental health, workplaces need to both prevent stress and promote PMH.

  20. Modified Nanodiamonds for Detoxification

    Science.gov (United States)

    Gibson, Natalie Marie

    essential for interacting with charged molecules, like OTA. Furthermore, the increased ZPs lead to improved colloidal stabilities over a wide range of pH, which is important for their interaction in the GI tract. While the dyes and OTA illustrated primarily electrostatic adsorption mechanisms, neutrally charged AfB1's adsorption was predominantly based upon the aggregate size of the ND substrate. In addition to mycotoxins, fluorescent dyes, including propidium iodide, pyranine and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), were initially utilized during methodological development. Fluorescent dye investigations helped assesses the adsorption mechanisms of NDs and demonstrated the significance of electrostatic interactions. Beyond electrostatic adsorption mechanisms, surface functional groups were also responsible for the amount of dye adsorbed, as was also true in OTA adsorption. Therefore, surface characterization was carried out for several ND samples by FTIR, TOF-SIMS and TDMS analysis. Final results of our studies show that our modified NDs perform better than yeast cells walls and other NDs but comparable to activated charcoal in the adsorption of AfB1, and outperform clay minerals in OTA studies. Moreover, it was demonstrated that adsorption can be maintained in a wide range of pH, thereby, increasing the possibility of NDs use in mycotoxins enterosorbent applications.

  1. Anomalous winter climate conditions in the Pacific rim during recent El Nino Modoki and El Nino events

    Energy Technology Data Exchange (ETDEWEB)

    Weng, Hengyi; Behera, Swadhin K. [Climate Variations Research Program, Frontier Research Center for Global Change/JAMSTEC, Yokohama (Japan); Yamagata, Toshio [Climate Variations Research Program, Frontier Research Center for Global Change/JAMSTEC, Yokohama (Japan)]|[University of Tokyo, Department of Earth and Planetary Science, Graduate School of Sciences, Tokyo (Japan)

    2009-04-15

    Present work compares impacts of El Nino Modoki and El Nino on anomalous climate in the Pacific rim during boreal winters of 1979-2005. El Nino Modoki (El Nino) is associated with tripole (dipole) patterns in anomalies of sea-surface temperature, precipitation, and upper-level divergent wind in the tropical Pacific, which are related to multiple 'boomerangs' of ocean-atmosphere conditions in the Pacific. Zonal and meridional extents of those 'boomerangs' reflect their independent influences, which are seen from lower latitudes in the west to higher latitudes in the east. In the central Pacific, more moisture is transported from the tropics to higher latitudes during El Nino Modoki owing to displacement of the wet 'boomerang' arms more poleward toward east. Discontinuities at outer 'boomerang' arms manifest intense interactions between tropical and subtropical/extratropical systems. The Pacific/North American pattern and related climate anomalies in North America found in earlier studies are modified in very different ways by the two phenomena. The seesaw with the dry north and the wet south in the western USA is more likely to occur during El Nino Modoki, while much of the western USA is wet during El Nino. The moisture to the southwestern USA is transported from the northward shifted ITCZ during El Nino Modoki, while it is carried by the storms traveling along the southerly shifted polar front jet during El Nino. The East Asian winter monsoon related anticyclone is over the South China Sea during El Nino Modoki as compared to its position over the Philippine Sea during El Nino, causing opposite precipitation anomalies in the southern East Asia between the two phenomena. (orig.)

  2. Puente sobre el Maracaibo

    Directory of Open Access Journals (Sweden)

    Equipo Editorial

    2017-05-01

    Full Text Available Para salvar el lago de Maracaibo (Venezuela, el conocido ingeniero italiano Riccaido Morandi ha presentado un proyecto de puente para ferrocarril y carretera, de hormigón pretensado, de tramos independientes, constituyendo un sistema Gerber, que tiene una longitud total de 8.720 m y un vano central de 400 m de luz. Este último tramo, en unión de los dos adyacentes al mismo, constituirán, una vez terminada la obra, un conjunto continuo. El tablero del puente se halla a una altura de 45 m sobre el nivel del agua en la zona del canal, con objeto de permitir la navegación. El tablero, de 20,90 m de anchura total, se ha subdividido en tres partes, dos simétricas respecto al eje, laterales, de 7,20 m de anchura, para la circulación en sentidos opuestos por carretera, una plataforma central, de 5 m de ancho, para el ferrocarril y dos andenes para el paso de peatones y servicios.

  3. El nombre comercial

    Directory of Open Access Journals (Sweden)

    Ernesto Rengifo García

    2013-11-01

    Full Text Available La figura del nombre comercial suele ser objeto de poco desarrollo conceptual en los cursos de derecho de propiedad industrial, e incluso en los manuales que sirven de sustento a aquellos, esto por cuanto, entre otras razones, existe la predisposición a abarcar el análisis de los signos distintivos con el estudio –ese sí exhaustivo– de la marca; y además porque el mismo legislador suele reenviar, para efectos de la integración normativa del nombre comercial, a lo por él dispuesto sobre las marcas de comercio. Sin embargo, el nombre comercial ha devenido un signo de primer orden y sus implicaciones son hoy tan trascendentales en el mundo del intercambio de bienes y servicios que no es suficiente para su estudio verlo como un mero apéndice del signo distintivo por excelencia, esto es, la marca. El artículo realiza una exposición de la regulación del nombre, y dentro de ella hace énfasis en sus falencias y en aquellos asuntos que, con contradicciones evidentes, pueden colocar a la institución del nombre comercial en problemas de interpretación o de incerteza frente a la seguridad que reclama un tráfico jurídico cada vez más intenso en el uso y posicionamiento de signos distintivos diferentes a las marcas.

  4. Nurse stress at two different organizational settings in Alexandria

    OpenAIRE

    Zaghloul, Ashraf

    2009-01-01

    Ashraf AZ Zaghloul, Nagwa Y Abou El EneinDepartment of Health Administration and Behavioural Sciences, High Institute of Public Health, University of Alexandria, Alexandria, EgyptObjective: The objective of the study was to explore the difference in stress levels among nurses working at two different health care organizations and the determinants of nurse stress within each organization. Job stress is defined as the harmful emotional and physical reactions resulting from the interactions betw...

  5. Las emociones en el profesorado: el afecto y el enfado como recursos para el disciplinamiento

    Directory of Open Access Journals (Sweden)

    Silvina Funes Lapponi

    Full Text Available Resumen Este artículo indaga lo que dice, piensa y siente el profesorado sobre la gestión de la disciplina en el aula y de cómo esto, a su vez, moldea la conducta y condiciona la participación y el desempeño del alumnado. Se basa en un estudio cualitativo (mediante entrevistas, cuaderno de campo, evaluación crítica de informantes claves que, a través del análisis del pensamiento pedagógico práctico (supuestos ideológicos tácitos, no conscientes que aparece en el discurso de los profesores, lo compara con la ideología pedagógica dominante (saberes formales e impuestos poniendo en evidencia una falta de coincidencia y coherencia entre ambos e influyendo esto, a su vez, en las relaciones en el aula. No se pretende descubrir algo nuevo, sino hacerlo visible y describir los mecanismos que intervienen. De este modo, se refuta una creencia muy extendida de que el mal clima del aula se debe a alumnos indisciplinados, ya que en las relaciones resultantes la reacción del docente es determinante. Centrándose en el afecto y el enfado, se observa cómo se crea un ambiente de trabajo, que convierte a estas emociones en herramientas para disciplinar, la primera de una manera más preventiva y la segunda más correctiva, es decir, que se constituyen en un recurso más para el control de la conducta de los alumnos.

  6. Bacterial stress

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Bacterial stress. Physicochemical and chemical parameters: temperature, pressure, pH, salt concentration, oxygen, irradiation. Nutritional depravation: nutrient starvation, water shortage. Toxic compounds: Antibiotics, heavy metals, toxins, mutagens. Interactions with other cells: ...

  7. (stress) testing

    African Journals Online (AJOL)

    However, maximal HR was significantly higher in all groups during their sporting activities than during stress testing in the laboratory (P < 0.01). Conclusions. Maximal HR in veteran athletes during specific sporting activities was significantly higher than that attained during a routine sECG. This finding was not sport-specific, ...

  8. PIPE STRESS and VERPIP codes for stress analysis and verifications of PEC reactor piping

    International Nuclear Information System (INIS)

    Cesari, F.; Ferranti, P.; Gasparrini, M.; Labanti, L.

    1975-01-01

    To design LMFBR piping systems following ASME Sct. III requirements unusual flexibility computer codes are to be adopted to consider piping and its guard-tube. For this purpose PIPE STRESS code previously prepared by Southern-Service, has been modified. Some subroutine for detailed stress analysis and principal stress calculations on all the sections of piping have been written and fitted in the code. Plotter can also be used. VERPIP code for automatic verifications of piping as class 1 Sct. III prescriptions has been also prepared. The results of PIPE STRESS and VERPIP codes application to PEC piping are in section III of this report

  9. El maltrato infantil

    OpenAIRE

    Mazo Toledo, María

    2014-01-01

    Se estudia el maltrato infantil desde sus antecedentes, así como su tipología, causas y consecuencias. Además de abordar el abuso sexual de forma más amplia. También se expone la evaluación psicológica junto con sus técnicas. Es fundamental la utilización de medidas para la prevención del maltrato infantil, pues una gran parte de los problemas en el niño se ven reflejados en su vida adulta

  10. en el contexto colombiano

    Directory of Open Access Journals (Sweden)

    Javier Giraldo

    2005-01-01

    Full Text Available Este artículo presenta el fenómeno del acoso laboral (mobbing como una situación disfuncional y frecuente en el contexto organizacional que, además, se perpetúa y es alimentada por la escalada simétrica de violencia que vive Colombia. Afrontar el fenómeno es una oportunidad para cumplir con la responsabilidad social, disciplinar y empresarial que favorece, a su vez, contextos de desarrollo éticos. Se propone una atención urgente tanto desde lo legal como de la psicología organizacional en aras de mejorar la calidad de vida laboral.

  11. El ciudadano digital

    Directory of Open Access Journals (Sweden)

    Carlos Arcila Calderón

    2014-12-01

    Full Text Available La sociedad de la información y la explosión informática han permitido el desarrollo de un nuevo esquema de consumo de mensajes, que convierten al habitante de una cibercomunidad en un ser democráticamente participativo y respetuoso de las subculturas emergentes. El comunicador debe crear vínculos estrechos con los usuarios para asistir a una cibercomunidad y convertirse en un mediador de espacios más democráticos y participativos. El Internet ha permitido tener la respuesta inmediata del receptor, quién a su vez puede transformarse en emisor.

  12. El hogar en red

    OpenAIRE

    Kennedy, Tracy L. M.; Wellman, Barry

    2008-01-01

    Proponemos que los individuos, en lugar de las solidaridades familiares, se han convertido en la principal unidad de conectividad en el hogar. Muchos hogares no funcionan como grupos tradicionales densamente conectados sino como redes sociales más dispersas donde los individuos tratan de hacer compatibles sus dispares horarios y agendas. En un momento en el que muchas personas ejercen múltiples roles individuales en casa, en la comunidad y en el trabajo nos preguntamos: ¿cómo se comunican ent...

  13. El veinte de Julio

    Directory of Open Access Journals (Sweden)

    Miguel Antonio Caro

    1960-07-01

    Full Text Available Fue un punto histórico y no una cuestión política, lo que ofrecimos a la consideración de nuestros lectores en el número de El Tradicionista, correspondiente al 23 de julio, al manifestar que, en nuestro concepto, el 20 del propio mes no era aniversario de la Independencia sino de la Revolución, como dicen nuestros historiadores, o, como decían también los próceres mismos, de la transformación política de 1810.

  14. Hipotiroidismo en el embarazo

    OpenAIRE

    Macchia, Carla Lorena; Sánchez-Flórez, Javier Augusto

    2007-01-01

    Introducción: el hipotiroidismo se presenta entre el 0,5 y 2,5% de todos los embarazos. La frecuencia es mayor si se consideran poblaciones de riesgo, como pacientes portadoras de enfermedades autoinmunes. Durante la gestación temprana existe dependencia de hormonas tiroideas maternas, puesto que la tiroides fetal es incapaz de elaborar sus productos hasta después del primer trimestre. En este periodo, toda situación de carencia puede ejercer efectos indeseables. Objetivo: el objetivo del pre...

  15. Bufalera El Porvenir

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    Heyner Castro S

    2011-11-01

    Full Text Available La finca el Porvenir está ubicada en San Rafael de Guatuso de Alajuela, en un pueblo llamado Mónico. La propiedad fue adquirida en el 2007 por la empresa denominada Academia RC Internacional S.A. la cual tenía la visión de convertirla en una finca criadora de búfalos de agua, ya que presentaba condiciones como llanuras y zonas inundables que favorecen esta práctica.A finales del 2007 se importó de Guatemala pie de cría, tanto hembras como machos; los animales poseían un perfil determinado y un alto mestizaje lechero, debido a que, en la finca de procedencia llevaban varios años mejorando el hato mediante la selección de los animales así como mejoramiento genético a través de la inseminación artificial utilizando butoros de las razas Murrah y Mediterránea principalmente.De este modo se inicia el desarrollo y mejoramiento del Porvenir enfocándose tanto en pastos como en infraestructura. Se construyeron instalaciones para la estabulación de animales, mangas y bretes para el manejo de estos, también se realizó una división de potreros para mejorar su rotación, ayudada por la instalación de cercas eléctricas.Durante el desarrollo de estas obras se consumió casi el primer año de trabajo por lo que durante este tiempo las búfalas no se ordeñaron y fueron mantenidas de una forma extensiva en donde los bucerros se criaron consumiendo toda leche.A finales del 2008 se inicia el ordeño a mano con un grupo de búfalas, esta práctica se realizó hasta que se terminó la sala de ordeño y se instaló completamente el equipo para el ordeño mecánico; luego de terminada la infraestructura se pudo tecnificar el ordeño hasta la actualidad.

  16. Distinguishing modified gravity from dark energy

    International Nuclear Information System (INIS)

    Bertschinger, Edmund; Zukin, Phillip

    2008-01-01

    The acceleration of the Universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark energy models. Modifications of general relativity are expected to be scale independent on superhorizon scales and scale dependent on subhorizon scales. For scale-independent modifications, utilizing the conservation of the curvature scalar and a parametrized post-Newtonian formulation of cosmological perturbations, we derive results for large-scale structure growth, weak gravitational lensing, and cosmic microwave background anisotropy. For scale-dependent modifications, inspired by recent f(R) theories we introduce a parametrization for the gravitational coupling G and the post-Newtonian parameter γ. These parametrizations provide a convenient formalism for testing general relativity. However, we find that if dark energy is generalized to include both entropy and shear stress perturbations, and the dynamics of dark energy is unknown a priori, then modified gravity cannot in general be distinguished from dark energy using cosmological linear perturbations.

  17. BREVES CONSIDERACIONES SOBRE EL BOXEO Y EL DERECHO

    OpenAIRE

    Brito, Luis Ariel Salanueva; Escuela Libre de Derecho (ELD)

    2016-01-01

    A través de una reflexión, el autor determina analogías entre el Derecho y el boxeo, donde da fe de las coincidencias que en cuestión de habilidades se presentan en ambas tareas, en ambos compromisos; haciendo de la abogacía, una profesión naturalmente relacionada con el pugilismo.

  18. Global Status of Genetically Modified Crops: Current Trends and Prospects

    OpenAIRE

    Hautea, Randy A.

    2002-01-01

    Modern biotechnology-facilitated crop improvement is undoubtedly one of the most significant technological developments in agriculture. The first wave of genetically-modified (GM) or transgenic crops include cultivars with important input traits such as herbicide tolerance and insect resistance. Future products are expected to provide benefits that could include tolerance to environmental stresses and enhanced nutritional content, which can be particularly valuable in crops that are important...

  19. Modified binders on the basis of flotation tailings

    Science.gov (United States)

    Shapovalov, N. A.; Zagorodnyuk, L. Kh; Shchekina, A. Yu; Gorodov, A. I.

    2018-03-01

    The article proposes compositions of efficient modified composite binders on the basis of portland cement and flotation tailings; the new binders attain the ultimate compressive stress that is twice as high as that of the cement stone. At that, use of annually growing volume of flotation tailings in the production of the composite binder is a rational way for recycling this type of waste and allows saving the planet's natural resources.

  20. Explosive compaction of aluminum oxide modified by multiwall carbon nanotubes

    Science.gov (United States)

    Buzyurkin, A. E.; Kraus, E. I.; Lukyanov, Ya L.

    2018-04-01

    This paper presents experiments and numerical research on explosive compaction of aluminum oxide powder modified by multiwall carbon nanotubes (MWCNT) and modeling of the stress state behind the shock front at shock loading. The aim of this study was to obtain a durable low-porosity compact sample. The explosive compaction technology is used in this problem because the aluminum oxide is an extremely hard and refractory material. Therefore, its compaction by traditional methods requires special equipment and considerable expenses.

  1. Piezotronically modified double Schottky barriers in ZnO varistors.

    Science.gov (United States)

    Raidl, Nadine; Supancic, Peter; Danzer, Robert; Hofstätter, Michael

    2015-03-25

    Double Schottky barriers in ZnO are modified piezotronically by the application of mechanical stresses. New effects such as the enhancement of the potential barrier height and the increase or decrease of the natural barrier asymmetry are presented. Also, an extended model for the piezotronic modification of double Schottky barriers is given. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. EL AMBIENTE Y EL DESARROLLO SUSTENTABLE EN LA CIUDAD LATINOAMERICANA

    OpenAIRE

    Luis Alfonso Sandia Rondón

    2009-01-01

    El Desarrollo Sustentable constituye el paradigma actual dominante para orientar el desarrollo económico y social de la humanidad. A pesar del aparente acuerdo global acerca de su importancia, su aplicación práctica es de difícil instrumentación, especialmente en el medio urbano latinoamericano, donde son múltiples las brechas que separan la ciudad actual de la deseada ciudad sustentable. Algunos aspectos para el análisis de la ciudad, el ambiente y el desarrollo sustentable son discutidos en...

  3. El rol del Estado en el Derecho Internacional Privado

    Directory of Open Access Journals (Sweden)

    Ruben B. Santos Belandro

    2015-09-01

    Full Text Available Contenido: Introducción. El Estado como instrumento de la racionalidad jurídica. Primer contragolpe en favor de la restauración de los valores irreflexivos: Savigny. La racionalidad jurídica al servicio del Estado: el neo-territorialismo rioplatense. Segundo contragolpe contra el racionalismo formal: el materialismo de Quintín Alfonsín. El reconocimiento de otras formas de racionalidad descartan al Estado como el único intérprete. ¿Y el futuro?

  4. Building on the Linguistic and Cultural Strengths of EL Students

    Science.gov (United States)

    Cowan, Kay; Sandefur, Sarah

    2013-01-01

    This article discusses an exemplary EL program grounded in research-based literacy strategies. World War II and the Holocaust served as the backdrop for a program that stressed vocabulary and concept development, and then connected that understanding to reading and writing. The "five streams" used to address literacy competencies included reading…

  5. MS Disease-Modifying Medications

    Science.gov (United States)

    ... disease-modifying therapies Approval: 2014 US; 2014 CAN Pregnancy Category C (see footnote, page 11) Rash, headache, fever, nasal congestion, nausea, urinary tract infection, fatigue, insomnia, upper respiratory tract infection, herpes viral ...

  6. Value Modifier Public Use File

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Center for Medicare (CM) has created a standard analytical file intended to promote transparency. For each Value Modifier performance year, CM will publish a...

  7. El tumor Krukenberg en el hombre

    OpenAIRE

    Alois, Mahlknecht; Valentina, Pecorari; Andreas, Gschwendeter

    2005-01-01

    OBJETIVOS: Las metástasis ováricas por un cáncer gastrointestinal son conocidas como tumor de Krukenberg. Presentamos un caso de metástasis testicular y de epidídimo por un cáncer gástrico que puede ser el caso análogo en el hombre. MATERIAL Y METODOS: Un paciente referido para gastrectomía total por un adenocarcinoma gástrico indiferenciado (Estadio TNM: pT3GIII N+ M1) desarrolló un año después una inflamación dolorosa de hemiescroto e ingle derechos. La palpación revelaba una masa dolorosa ...

  8. El efecto invernadero

    OpenAIRE

    Sánchez Vega, Marco Vinicio

    2016-01-01

    El aumento de la concentración de los gases conocidos como de efecto invernadero, tales como el dióxido de carbono, el metano y los óxidos de nitrógeno, entre otros, hace que la atmósfera retenga un porcentaje superior del calor emitido por la Tierra, produciéndose un calentamiento global. Este calentamiento podría, si alcanzara niveles críticos, fundir parte de los casquetes polares, lo que elevaría el nivel de los mares, provocando inundaciones de algunas zonas costeras donde se concentra u...

  9. El Dimoni de Maxwell

    OpenAIRE

    Monserrat, Bartomeu

    2010-01-01

    El dimoni de Maxwell és el resultat d'un experiment mental que va proposar el físic escocès James Clerk Maxwell (1831-1879), que si es complís amenaçaria la validesa de la segona llei de la termodinàmica. Segons aquest experiment, seria possible la transmissió de calor d'un cos a un altre de més calent sense cap altre canvi. S'hi ex- posen diverses solucions, que van des de la interacció entre la mesura i el sistema mesurat, fins a la teoria de la informació. Aquest article, origi...

  10. y el Reino Unido.

    Directory of Open Access Journals (Sweden)

    Eutimio Mejía Soto

    2006-01-01

    Full Text Available La estandarización internacional contable ha generado una dinámica en los procesos de regulación internacional; busca la uniformidad de los procedimientos contables en el registro, preparación y presentación de los diferentes rubros que componen los estados financieros. Dichos rubros presentan en la actualidad divergencias en sus criterios de reconocimiento, valoración, medición y revelación. El presente artículo relaciona los criterios contables establecidos para el tratamiento de los activos intangibles de los organismos reguladores de Colombia, Canadá, Chile, México, Estados Unidos, España, Reino Unido y el modelo de estandarización internacional del IASB.

  11. El Astero de plata

    Directory of Open Access Journals (Sweden)

    Edmundo Motta Zamalloa

    1988-12-01

    Full Text Available Tres propósitos animan al presente trabajo: mostrar la conversión del toro en una entidad cultural a partir de un contexto definido económica y socialmente por el agrarismo, en el que el elemento toro se constituyó históricamente en la fuerza de tracción más importante entre los instrumentos de producción. De otra parte, cómo la capitalización de la agricultura y la secuela de modernización termina por transferir el control de este espectáculo a una burguesía agraria. Y, finalmente, su empleo metafórico en una relación social de tipo conflictivo.

  12. y El Alto, Bolivia

    Directory of Open Access Journals (Sweden)

    León Darío Parra Bernal

    2013-01-01

    Full Text Available En el presente caso de estudio se analiza la empresarialidad informal como un reto de política pública y económica. Para ello, se efectuaron 20 entrevistas en profundidad a microempresarios y comerciantes del sector informal en las ciudades de La Paz y El Alto, en Bolivia en 2010, y a 3 funcionarios públicos de instituciones de apoyo al fomento empresarial en el mismo país. La principal reflexión giró en torno al establecimiento de que los empresarios informales poseen un elevado nivel de influencia en la efectividad de las políticas públicas implementadas para su sector, así como en los mecanismos que se han utilizado en Bolivia para incluirlos en el proceso.

  13. Izalco, El Salvador Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Izalco is a young stratovolcano on the south flank of Santa Ana Volcano in western El Salvador. Its continuous small explosive eruptions (beginning in 1770) caused...

  14. Democratizando el ciberespacio

    Directory of Open Access Journals (Sweden)

    Howard Frederick

    2015-01-01

    Full Text Available Las redes electrónicas y las tecnologías descentralizadas se proponen democratizar, humanizar y civilizar el ciberespacio. William Gibson, escritor de ciencia ficción, dijo que el ciberespacio es una alucinación consensual, una representación gráfica de datos abstraídos de los bancos de cada computador en el sistema humano. Ofrece conceptos sobre cibernética, sociedad global, ciberespacio, etc. Para asegurar los derechos a la comunicación e información emergió una red global de comunicación por computadores para favorecer el bienestar común de la humanidad. Los medios modernos de comunicación han entrelazado algunas regiones del mundo con una telaraña electrónica. En correspondencia a esta evolución ha surgido un nuevo actor en las relaciones internacionales: la sociedad civil global.

  15. Entre el negocio y el temor

    OpenAIRE

    Francisco Ficarra

    2015-01-01

    Se pretende dar una primera panorámica del tema virus informáticos y todas sus derivaciones. Se habla de la vulnerabilidad de las redes, de la etimología y evolución poco saludable, tipología de virus, los antídotos y conclusiones como: la red de redes tiene un talón de Aquiles con el tema de los virus informáticos.

  16. Conciliación y salud laboral: ¿una relación posible?: Actualidad en el estudio del conflicto trabajo-familia y la recuperación del estrés Work-family balance and occupational health: Is this relationship possible?: Current situation in the study of work-family conflict and recovery from stress

    Directory of Open Access Journals (Sweden)

    Ana Isabel Sanz Vergel

    2011-01-01

    Full Text Available Los cambios económicos y sociales de los últimos años han generado nuevas estructuras organizacionales y familiares que afectan a los trabajadores. Aparecen así nuevos riesgos psicosociales, como el conflicto entre la vida laboral y familiar. Para poder enfrentarse a las demandas del trabajo y de la familia, es necesario tener un tiempo para recuperarnos del esfuerzo realizado. Así pues, para mejorar la calidad de vida del empleado, es necesario atender al bienestar de la persona en su conjunto. El objetivo del presente artículo es revisar las principales líneas de investigación surgidas en las últimas décadas en torno a estos temas. En primer lugar, se analizan los factores antecedentes del conflicto trabajo-familia así como sus consecuencias y diversas variables que intervienen en este proceso. Posteriormente, se examina la literatura reciente sobre "recuperación del estrés", atendiendo a las estrategias que pueden ayudar a los trabajadores a superar los esfuerzos llevados a cabo en la rutina diaria. Por último, se presentan las principales líneas de prevención e intervención a nivel organizacional e individual, dirigidas a reducir los estresores laborales, promover políticas de conciliación y desarrollar estrategias de recuperación.The economic and social changes of the last years have created new organizational and family structures that affect workers. As a result, new psychosocial risks appear, as the conflict between work and family life. To meet work and family demands, people need time to recover from the expended effort. Thus, to improve the quality of life of the employee, it is necessary to attend to the well-being of the person in general. The aim of this paper is to review the main lines of research emerged during the last decades on these topics. First, we analyze the background and consequences of work-family conflict as well as the main variables affecting this process. Second, we examine recent literature on

  17. EL SECRETO PROFESIONAL ANTE EL NOTARIO

    Directory of Open Access Journals (Sweden)

    Ignacio Vidal Domínguez

    2002-01-01

    Full Text Available Nuestra legislación en general se encuentra inspirada en el principio de la publicidad registral. Por lo mismo llama la atención que en lo notarial pueda existir algo "secreto". No existe en los protocolos a cargo de los notarios nada que sea privado. Lo mismo ocurre con respecto a los registros y libros a cargo de conservadores y archiveros judiciales. Sin embargo no es tan así de simple. Las líneas que siguen pretenden dar algunas luces sobre el tema, casi no tratado hasta ahora, al menos en nuestra doctrina, no así en la extranjera. El tema en absoluto está agotado. Nuestra pretensión es entregar los primeros esbozos para un estudio más acabado.In general, our legislation is based on the principals of registering publicity. Therefore, it calls our attention the fact that there can be something "secret" in the notarial. There does not exist anything that is private in the protocol in charge of the notaries. It is the same with records and books, which the legal preservers and file clerks are in charge of. However, it is not that simple. The guidelines they follow try to give some light on this subject, which has hardly been dealt with until now, at least in our area, although it has been touched abroad. The subject has not run out. We intend to give the first outlines for a more profound study.

  18. en el contexto latinoamericano

    Directory of Open Access Journals (Sweden)

    Selin Carrasco

    2016-01-01

    Full Text Available Desde la Cátedra Investigación Educativa II de la Universidad Nacional de San Luis, Argentina, nos preguntamos acerca de la pertinencia de los contenidos y valor de las estrategias de enseñanza que se utilizan para formar en investigación a los futuros profesionales de la educación y asumimos el reto de repensar la disciplina misma y su enseñanza en el contexto de la sociedad actual. Se analizó la investigación a la luz de las nueva tecnologías y el desarrollo de lo digital, se indagó la expresión que esto adopta en el contexto latinoamericano y se planificó una experiencia de trabajo innovadora para los estudiantes de cuarto año del Profesorado y la Licenciatura en Ciencias de la Educación, con un enfoque de enseñanza centrado en el estudiante, y acciones que devienen de los principios del aprendizaje invertido, aprendizaje extendido y trabajo colaborativo. El artículo profundiza la relación que se establece entre investigación educativa, tecnología y enseñanza de la investigación; y promueve la reflexión en torno al impacto que la misma puede tener sobre los contenidos de la formación de investigadores, los procesos de formación, el perfil de los investigadores y la investigación educativa misma. Relata los principios de los que se partió en la experiencia, el modo como se trabajó, los aspectos más valorados y los considerados críticos o que requieren más atención y estudio. Cierra con unas reflexiones generales.

  19. El trastorno obsesivo compulsivo

    OpenAIRE

    Navarro Miranda, María José

    2014-01-01

    El trastorno obsesivo compulsivo y su tr atamiento se ve altamente dificultado porque a menudo los propios afectados no solicitan ayuda terapéutica por vergüenza o miedo a ser rechazados; incluso muchos de ellos ni siquiera comunican el problema a sus familiares más próximos . Por ello, los expertos se refieren al trastorno obsesivo como la “enfermedad secreta

  20. El lenguaje del pensamiento

    Directory of Open Access Journals (Sweden)

    Alberto Andreu Marín

    2017-09-01

    Full Text Available ¿Somos capaces de interpretar las señales eléctricas que genera nuestro cerebro cuando estamos pensando? Lo que a priori parece ciencia ficción comienza a ser factible gracias a los avances recientes en técnicas de registro cerebral y en aprendizaje automático. Nos encontramos en el inicio de una nueva era en lo que al conocimiento del cerebro se refiere.