Search results for: posttraumatic stress disorder

Authors: Mohammad Hossein Bayati Chaleshtari, Hadi Khoramishad

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Minimizing the stress concentration around triangular cutout in infinite perforated plates subjected to a uniform heat flux induces thermal stresses is an important consideration in engineering design. Furthermore, understanding the effective parameters on stress concentration and proper selection of these parameters enables the designer to achieve a reliable design. In the analysis of thermal stress, the effective parameters on stress distribution around cutout include fiber angle, flux angle, bluntness and rotation angle of the cutout for orthotropic materials. This paper was tried to examine effect of these parameters on thermal stress analysis of infinite perforated plates with central triangular cutout. In order to achieve the least amount of thermal stress around a triangular cutout using a novel swarm intelligence optimization technique called dragonfly optimizer that inspired by the life method and hunting behavior of dragonfly in nature. In this study, using the two-dimensional thermoelastic theory and based on the Likhnitskiiʼ complex variable technique, the stress analysis of orthotropic infinite plate with a circular cutout under a uniform heat flux was developed to the plate containing a quasi-triangular cutout in thermal steady state condition. To achieve this goal, a conformal mapping function was used to map an infinite plate containing a quasi- triangular cutout into the outside of a unit circle. The plate is under uniform heat flux at infinity and Neumann boundary conditions and thermal-insulated condition at the edge of the cutout were considered.

Keywords: infinite perforated plate, complex variable method, thermal stress, optimization method

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Authors: Yang Zhong, Mei-Jie Xu

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To study the dynamic mechanics response of asphalt pavement under the temperature load and vehicle loading, asphalt pavement was regarded as multilayered elastic half-space system, and theory analysis was conducted by regarding dynamic modulus of asphalt mixture as the parameter. Firstly, based on the dynamic modulus test of asphalt mixture, function relationship between the dynamic modulus of representative asphalt mixture and temperature was obtained. In addition, the analytical solution for thermal stress in the single layer was derived by using Laplace integral transformation and Hankel integral transformation respectively by using thermal equations of equilibrium. The analytical solution of calculation model of thermal stress in asphalt pavement was derived by transfer matrix of thermal stress in multilayer elastic system. Finally, the variation of thermal stress in pavement structure was analyzed. The result shows that there is an obvious difference between the thermal stress based on dynamic modulus and the solution based on static modulus. Therefore, the dynamic change of parameter in asphalt mixture should be taken into consideration when the theoretical analysis is taken out.

Keywords: asphalt pavement, dynamic modulus, integral transformation, transfer matrix, thermal stress

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Authors: Fellah Sihem

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The optimal use of soil moisture by culture, is related to the leaf area index, which stood in the cycle and its modulation according to the prevailing stress intensity. For a given stock of water in the soil, cultivar adapted and saving water is one that is no luxury consumption during the preanthesis. It modulates the leaf area index to regulate sweating in the degree of its water supply. In plants water saving, avoidance of dehydration is related to the reduction of water loss by cuticular and stomatal pathways. Muchow and Sinclair reported that the test of relative water content (TRE) is considered the best indicator of leaf water status. The search for indicators of the ability of the plant to make good use of the water, under water stress is a prerequisite for progress in improving performance under water stress. This experiment aims to characterize a set of durum wheat varieties, tested jars and vegetation under different levels of water stress to the surface of the leaf, relative water content, cell integrity, the accumulated biomass and efficiency of water use. The experiment was conducted during the 2005/2006 academic year, at the Agricultural Research Station of the Field Crop Institute of Setif, under semi-controlled conditions. Five genotypes of durum wheat (Triticum durum Desf) were evaluated for their ability to tolerate moderate and severe water stress. The results showed that geno types respond differently to water stress. Dry matter accumulation and growth rate varied among geno types and were significantly reduced. At severe water stress biomass accumulated by Boussalam was the least affected.

Keywords: water stress, triticum durum, biomass, cell membrane integrity, relative water content

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Authors: M. Trousselard, D. Steiler, C. Drogou, P. van-Beers, G. Lamour, S. N. Crosnier, O. Bouilland, P. Dubost, M. Chennaoui, D. Léger

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According to published data, undersea navigation for long periods (nuclear-powered ballistic missile submarine, SSBN) constitutes an extreme environment in which crews are subjected to multiple stresses, including the absence of natural light, illuminance below 1,000 lux, and watch schedules that do not respect natural chronobiological rhythms, for a period of 60-80 days. These stresses seem clearly detrimental to the submariners’ sleep, with consequences for their affective (seasonal affective disorder-like) and cognitive functioning. In the long term, there are abundant publications regarding the consequences of sleep disruption for the occurrence of organic cardiovascular, metabolic, immunological or malignant diseases. It seems essential to propose countermeasures for the duration of the patrol in order to reduce the negative physiological effects on the sleep and mood of submariners. Light therapy, the preferred treatment for dysfunctions of the internal biological clock and the resulting seasonal depression, cannot be used without data to assist knowledge of submariners’ chronobiology (melatonin secretion curve) during patrols, given the unusual characteristics of their working environment. These data are not available in the literature. The aim of this project was to assess, in the course of two studies, the benefits of two environmental techniques for managing chronobiological stress: techniques for optimizing potential (TOP; study 1)3, an existing programme to help in the psychophysiological regulation of stress and sleep in the armed forces, and dawn and dusk simulators (DDS, study 2). For each experiment, psychological, physiological (sleep) or biological (melatonin secretion) data were collected on D20 and D50 of patrol. In the first experiment, we studied sleep and depressive distress in 19 submariners in an operational setting on board an SSBM during a first patrol, and assessed the impact of TOP on the quality of sleep and depressive distress in these same submariners over the course of a second patrol. The submariners were trained in TOP between the two patrols for a 2-month period, at a rate of 1 h of training per week, and assigned daily informal exercises. Results show moderate disruptions in sleep pattern and duration associated with the intensity of depressive distress. The use of TOP during the following patrol improved sleep and depressive mood only in submariners who regularly practiced the techniques. In light of these limited benefits, we assessed, in a second experiment, the benefits of DDS on chronobiology (daily secretion of melatonin) and depressive distress. Ninety submariners were randomly allocated to two groups, group 1 using DDS daily, and group 2 constituting the control group. Although the placebo effect was not controlled, results showed a beneficial effect on chronobiology and depressive mood for submariners with a morning chronotype. Conclusions: These findings demonstrate the difficulty of practicing the tools of psychophysiological management in real life. They raise the question of the subjects’ autonomy with respect to using aids that involve regular practice. It seems important to study autonomy in future studies, as a cognitive resource resulting from the interaction between internal positive resources and “coping” resources, to gain a better understanding of compliance problems.

Keywords: chronobiology, light therapy, seasonal affective disorder, sleep, stress, stress management, submarine

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Authors: Rohit Shrivastava, Stefan Luding

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A mechanical wave is propagation of vibration with transfer of energy and momentum. Studying the energy as well as spectral energy characteristics of a propagating wave through disordered granular media can assist in understanding the overall properties of wave propagation through inhomogeneous materials like soil. The study of these properties is aimed at modeling wave propagation for oil, mineral or gas exploration (seismic prospecting) or non-destructive testing for the study of internal structure of solids. The study of Energy content (Kinetic, Potential and Total Energy) of a pulse propagating through an idealized one-dimensional discrete particle system like a mass disordered granular chain can assist in understanding the energy attenuation due to disorder as a function of propagation distance. The spectral analysis of the energy signal can assist in understanding dispersion as well as attenuation due to scattering in different frequencies (scattering attenuation). The selection of one-dimensional granular chain also helps in studying only the P-wave attributes of the wave and removing the influence of shear or rotational waves. Granular chains with different mass distributions have been studied, by randomly selecting masses from normal, binary and uniform distributions and the standard deviation of the distribution is considered as the disorder parameter, higher standard deviation means higher disorder and lower standard deviation means lower disorder. For obtaining macroscopic/continuum properties, ensemble averaging has been used. Interpreting information from a Total Energy signal turned out to be much easier in comparison to displacement, velocity or acceleration signals of the wave, hence, indicating a better analysis method for wave propagation through granular materials. Increasing disorder leads to faster attenuation of the signal and decreases the Energy of higher frequency signals transmitted, but at the same time the energy of spatially localized high frequencies also increases. An ordered granular chain exhibits ballistic propagation of energy whereas, a disordered granular chain exhibits diffusive like propagation, which eventually becomes localized at long periods of time.

Keywords: discrete elements, energy attenuation, mass disorder, granular chain, spectral energy, wave propagation

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Authors: Simona Capossela, Ramona Schaniel, Singer Franziska, Aquino Fournier Catharine, Daniel Stekhoven, Jivko Stoyanov

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A spinal cord injury (SCI) is a traumatic life event that often results in ageing associated health conditions such as muscle mass decline, adipose tissue increase, decline in immune function, frailty, systemic chronic inflammation, and psychological distress and depression. Psychological, oxidative, and metabolic stressors may facilitate accelerated ageing in the SCI population with reduced life expectancy. Research designs using biomarkers of aging and stress are needed to elucidate the role of psychological distress in accelerated aging. The aim of this project is a feasibility pilot study to observe changes in stress biomarkers and correlate them with aging markers in SCI patients during their first rehabilitation (longitudinal cohort study). Biological samples were collected in the SwiSCI (Swiss Spinal Cord Injury Cohort Study) Biobank in Nottwil at 4 weeks±12 days after the injury (T1) and at the end of the first rehabilitation (discharge, T4). The "distress thermometer" is used as a selfassessment tool for psychological distress. Stress biomarkers, as cortisol and protein carbonyl content (PCC), and markers of cellular aging, such as telomere lengths, will be measured. 2 Preliminary results showed that SCI patients (N= 129) are still generally distressed at end of rehabilitation, however we found a statistically significant (p< 0.001) median decrease in distress from 6 (T1) to 5 (T4) during the rehabilitation. In addition, an explorative transcriptomics will be conducted on N=50 SCI patients to compare groups of persons with SCI who have different trajectories of selfreported distress at the beginning and end of the first rehabilitation after the trauma. We identified 4 groups: very high chronic stress (stress thermometer values above 7 at T1 and T4; n=14); transient stress (high to low; n=14), low stress (values below 5 at T1 and T4; n=14), increasing stress (low to high; n=8). The study will attempt to identify and address issues that may occur in relation to the design and conceptualization of future study on stress and aging in the SCI population.

Keywords: stress, aging, spinal cord injury, biomarkers

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Authors: S. Asreazad

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This paper presents the results that the soil volumetric strain and shear strength are closely related to the confining stress and initial matric suction under constant water content testing on the specimens of unsaturated sand with clay and silt fines contents. The silty sand specimens reached their peak strength after a very small axial strain followed by a post-peak softening towards an ultimate value. The post-peak drop in stress increased by an increment of the suction, while there is no peak strength for clayey sand specimens. The clayey sand shows compressibility and possesses ductile stress-strain behaviour. Shear strength increased nonlinearly with respect to matric suction for both soil types. When suction exceeds a certain range, the effect of suction on shear strength increment weakens gradually. Under the same confining stress, the dilatant tendencies in the silty sand increased under lower values of suction and decreased for higher suction values under the same confining stress. However, the amount of contraction increased with increasing initial suction for clayey sand specimens.

Keywords: unsaturated soils, silty sand, clayey sand, triaxial test

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Authors: H. Gholami, M. Jalali Azizpour

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Stress Corrosion Crack (SCC) in pipeline is a type of environmentally assisted cracking (EAC), since its discovery in 1965 as a possible cause of failure in pipeline, SCC has caused, on average, one of two failures per year in the U.S, According to the NACE SCC DA a pipe line segment is considered susceptible to SCC if all of the following factors are met: The operating stress exceeds 60% of specified minimum yield strength (SMYS), the operating temperature exceeds 38°C, the segment is less than 32 km downstream from a compressor station, the age of the pipeline is greater than 10 years and the coating type is other than Fusion Bonded Epoxy(FBE). In this paper as a practical experience in NISOC, Direct Assessment (DA) Method is used for identification SCC defect in unpiggable pipeline located downstream of compressor station.

Keywords: stress corrosion crack, direct assessment, disbondment, transgranular SCC, compressor station

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Authors: Teris Cheung, Joyce Yuen Ting Lam, Kwan Hin Fong, Yuen Shan Ho, Tim Man Ho Li, Andy Choi-Yeung Tse, Cheng-Ta Li, Calvin Pak-Wing Cheng, Roland Beisteiner

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Transcranial pulse stimulation (TPS) is a non-intrusive brain stimulation technology that has been proven effective in older adults with mild neurocognitive disorders and adults with major depressive disorder. Given these robust evidences, TPS might be an adjunct treatment options in neuropsychiatric disorders, for example, autism spectrum disorder (ASD) – which is a common neurodevelopmental disorder in children. This trial aimed to investigate the effects of TPS on right temporoparietal junction, a key node for social cognition for Autism Spectrum Disorder (ASD), and to examine the association between TPS, executive functions and social functions. Design: This trial adopted a two-armed (verum TPS group vs. sham TPS group), double-blinded, randomized, sham-controlled design. Sampling: 32 subjects aged between 12 and 17, diagnosed with ASD were recruited. All subjects were computerized randomized into either verum TPS group or the sham TPS group on a 1:1 ratio. All subjects undertook functional MRI before and after the TPS interventions. Intervention: Six 30-min TPS sessions were administered to subjects in 2 weeks’ time on alternate days assessing neural connectivity changes. Baseline measurements and post-TPS evaluation of the ASD symptoms, executive functions, and social functions were conducted. Participants were followed up at 2-weeks, at 1-month and 3-month, assessing the short-and long-term sustainability of the TPS intervention. Data analysis: Generalized Estimating Equations with repeated measures were used to analyze the group and time difference. Missing data were managed by multiple imputations. The level of significance was set at p < 0.05. To our best knowledge, this is the first study evaluating the efficacy and safety of TPS among adolescents with ASD in Hong Kong and nationwide. Results emerging from this study will develop insight on whether TPS can be used as an adjunct treatment on ASD in neuroscience and clinical psychiatry. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT05408793.

Keywords: adolescents, autism spectrum disorder, neuromodulation, rct, transcranial pulse stimulation

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Authors: B. Padmaja, V. V. Rama Prasad, K. V. N. Sunitha, E. Krishna Rao Patro

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Stress is a psychological condition that reduces the quality of sleep and affects every facet of life. Constant exposure to stress is detrimental not only for mind but also body. Nevertheless, to cope with stress, one should first identify it. This paper provides an effective method for the cognitive stress level detection by using data provided from a physical activity tracker device Fitbit. This device gathers people’s daily activities of food, weight, sleep, heart rate, and physical activities. In this paper, four major stressors like physical activities, sleep patterns, working hours and change in heart rate are used to assess the stress levels of individuals. The main motive of this system is to use machine learning approach in stress detection with the help of Smartphone sensor technology. Individually, the effect of each stressor is evaluated using logistic regression and then combined model is built and assessed using variants of ordinal logistic regression models like logit, probit and complementary log-log. Then the quality of each model is evaluated using Akaike Information Criterion (AIC) and probit is assessed as the more suitable model for our dataset. This system is experimented and evaluated in a real time environment by taking data from adults working in IT and other sectors in India. The novelty of this work lies in the fact that stress detection system should be less invasive as possible for the users.

Keywords: physical activity tracker, sleep pattern, working hours, heart rate, smartphone sensor

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Authors: Mahdieh Khanmohammadi, Sune Darkner, Nicoletta Nava, Jens Randel Nyengaard, Jon Sporring

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We study the effect of stress on nervous system and we use two experimental groups of rats: sham rats and rats subjected to acute foot-shock stress. We investigate the synaptic vesicles density as a function of distance to the active zone in serial section transmission electron microscope images in 2 and 3 dimensions. By estimating the density in 2D and 3D we compare two groups of rats.

Keywords: stress, 3-dimensional synaptic vesicle density, image registration, bioinformatics

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Authors: Mitchell Gohnert

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This paper reviews some fundamental concepts of structural optimization, which is based on the type of materials used in construction and the shape of the structure. The first step in structural optimization is to break down all internal forces in a structure into fundamental stresses, which are tensions and compressions. Knowing the stress patterns directs our selection of structural shapes, and the most appropriate type of construction material. In our selection of materials, it is essential to understand all construction materials have flaws, or micro-cracks, which reduce the capacity of the material, especially when subjected to tensions. Because of material defects, many construction materials perform significantly better when subjected to compressive forces. Structures are also more efficient if bending moments are eliminated. Bending stresses produce high peak stresses at each face of the member, and therefore substantially more material is required to resist bending. The shape of the structure also has a profound effect on stress levels. Stress may be reduced dramatically by simply changing the shape. Catenary, triangular and linear shapes are the fundamental structural forms to achieve optimal stress flow. If the natural flow of stress matches the shape of the structures, the most optimal shape is determined.

Keywords: Shell structures, structural optimization, Stress flow, Construction materials, catenary shapes

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Authors: Ayelet Siman-Tov, Shlomo Kaniel

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Objectives: The research validates a multivariate model that predicts parental adjustment to coping successfully with an autistic child. The model comprises four elements: parental stress, parental resources, parental adjustment and the child's autism symptoms. Background and aims: The purpose of the current study is the construction and validation of a model for the adjustment of parents and a child with autism. The suggested model is based on theoretical views on stress and links personal resources, stress, perception, parental mental health and quality of marriage and child adjustment with autism. The family stress approach focuses on the family as a system made up of a dynamic interaction between its members, who constitute interdependent parts of the system, and thus, a change in one family member brings about changes in the processes of the entire family system. From this perspective, a rise of new demands in the family and stress in the role of one family member affects the family system as a whole. Materials and methods: 176 parents of children aged between 6 to 16 diagnosed with ASD answered several questionnaires measuring parental stress, personal resources (sense of coherence, locus of control, social support), adjustment (mental health and marriage quality) and the child's autism symptoms. Results: Path analysis showed that a sense of coherence, internal locus of control, social support and quality of marriage increase the ability to cope with the stress of parenting an autistic child. Directions for further research are suggested.

Keywords: stress, adjustment, resources, Autism, parents, coherence

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Authors: Vivian A. Panes, Raymond John S. Rebong, Miel Q. Diaz

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Moringa oleifera Lam. is known mainly for its high nutritional value and medicinal properties contributing to its popular reputation as a 'miracle plant' in the tropical climates where it usually grows. The main objective of this study is to discover the genes and gene products involved in abiotic stress-induced activity that may impact the M. oleifera Lam. mature seeds as well as their corresponding functions. In this study, RNA-sequencing and de novo transcriptome assembly were performed using two assemblers, Trinity and Oases, which produced 177,417 and 120,818 contigs respectively. These transcripts were then subjected to various bioinformatics tools such as Blast2GO, UniProt, KEGG, and COG for gene annotation and the analysis of relevant metabolic pathways. Furthermore, FPKM analysis was performed to identify gene expression levels. The sequences were filtered according to the 'response to stress' GO term since this study dealt with stress response. Clustered Orthologous Groups (COG) showed that the highest frequencies of stress response gene functions were those of cytoskeleton which make up approximately 14% and 23% of stress-related sequences under Trinity and Oases respectively, recombination, repair and replication at 11% and 14% respectively, carbohydrate transport and metabolism at 23% and 9% respectively and defense mechanisms 16% and 12% respectively. KEGG pathway analysis determined the most abundant stress-response genes in the phenylpropanoid biosynthesis at counts of 187 and 166 pathways for Oases and Trinity respectively, purine metabolism at 123 and 230 pathways, and biosynthesis of antibiotics at 105 and 102. Unique and cumulative GO term counts revealed that majority of the stress response genes belonged to the category of cellular response to stress at cumulative counts of 1,487 to 2,187 for Oases and Trinity respectively, defense response at 754 and 1,255, and response to heat at 213 and 208, response to water deprivation at 229 and 228, and oxidative stress at 508 and 488. Lastly, FPKM was used to determine the levels of expression of each stress response gene. The most upregulated gene encodes for thiamine thiazole synthase chloroplastic-like enzyme which plays a significant role in DNA damage tolerance. Data analysis implies that M. oleifera stress response genes are directed towards the effects of climate change more than other stresses indicating the potential of M. oleifera for cultivation in harsh environments because it is resistant to climate change, pathogens, and foreign invaders.

Keywords: stress response, genes, Moringa oleifera, transcriptomics

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Authors: José Nogueira

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This research aims to analyze the impact of autism spectrum disorders (ASD) in families with children and youth (0-25 years) with ASD in Portugal. The impact will be evaluated on a multidimensional perspective, following the work on the concept of quality life from WHOQOL Group (UN). The study includes quantitative and qualitative methodology. It correlates statistical sources and other information with the data obtained through a survey of a sample of about 100 families with children/youth with ASD (October and November 2013). The results indicate a strong impact of autism on the quality of life for families in all study dimensions. The research shows a negative impact on quality of life for families in material and financial conditions, physical and emotional well-being, career progression, feelings of injustice, social participation and self-perception of happiness. The quality of life remained in the relationship with the family and the spouse, interpersonal relationships and beliefs about himself. The ASD improved the quality of life aspects such as interest, knowledge and exercise of rights on disability, autonomy to make decisions and be able to deal with stress. Other dimensions are contemplated: a detailed characterization of the child/young with ASD and all family members (household composition, relationship status, academic qualifications, occupation, income, and leisure) the impact of diagnosis in the family wellbeing, medical and therapeutic processes, school inclusion, public support, social participation, and the adequacy and implementation of legislation. The study evaluates also the strengths and weaknesses of the Portuguese public rehabilitation system and demonstrates how a good law-in-theory may not solve the problems of families in practice due to the allocation of insufficient public resources, both financial and human resources.

Keywords: autism, families, quality of life, autism spectrum disorder

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Authors: Katalin Gocze, Vanda A Nemes, Charlotte Briest

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Introduction: Premenstrual syndrome (PMS) is a psychoneuroendocrinological disorder adversely affecting life-quality for over 80% of hormonally active women. PMS has a negative impact on women’s daily life in terms of work, interpersonal relationships and leisure time activities. The aim of our study was to evaluate the effects of a yoga intervention focusing on the female pelvic area. Materials and methods: 34 women (ages 18-40) with PMS (Premenstrual Syndrome Screening Tool) and no previous experience in yoga were recruited and randomly assigned to either the yoga or the control group. The intervention consisted of 90’ yoga sessions twice a week and a daily 15’ self-practice module with carefully chosen yogic exercises addressing the reproductive organs by toning the pelvic floor and opening the hips as well as relieving stress and improving concentration. Severity of symptoms of PMS was assessed at the beginning and after the 8-week-long intervention. Pre- and post-program data collection included physical and psychological parameters and the evaluation of ACOQ PMS questionnaire and daily symptom diary. Results: Age and educational background were similar in the control and intervention group with an overall mean age of 29.11±4.78 years. PSST scores significantly improved in the yoga group (p=0.002), while difference in the control group’s pre and post-program values were non-significant (p=0.38). Perception and tolerance of anxiety and stress was significantly better after the intervention (p=0.008). As for changes in physical symptoms distinct improvement was registered for breast tenderness (p=0.028) and for meteorism (p=0.015). Discussion: Yoga’s success originates from the synergic positive effects of stress relief and regular physical activity. Benefits (both mental and physical) of strategically planned, focused yoga practice are apparent even after shorter time periods and can help women with PMS manage or eliminate symptoms in order to improve their life-quality.

Keywords: life-quality, physical symptoms, premenstrual syndrome, psychological impact, yoga

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Authors: Soo-yeon Seo, Seol-ki Kim, Su-jin Jung

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In the construction of a building, it is necessary to minimize construction period and secure enough work space for stacking of materials during the construction especially in city area. In this manner, various top-down construction methods have been developed and widely used in Korea. This paper investigates the stress variation of underground structure of a building constructed by using SPS (Strut as Permanent System) known as a top-down method in Korea through an analytical approach. Various types of earth pressure distribution related to ground condition were considered in the structural analysis of an example structure at each step of the excavation. From the analysis, the most high member force acting on beams was found when the ground type was medium sandy soil and a stress concentration was found in corner area.

Keywords: construction of building, top-down construction method, earth pressure distribution, member force, stress concentration

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Authors: Pratch Kittipongpattana, Thongchai Fongsamootr

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This research aimed to study the influences of a soot blowing operation and geometrical variables to the stress characteristic of water wall tubes located in soot blowing areas which caused the boilers of Mae Moh power plant to lose their generation hour. The research method is divided into 2 parts (a) measuring the strain on water wall tubes by using 3-element rosette strain gages orientation during a full capacity plant operation and in periods of soot blowing operations (b) creating a finite element model in order to calculate stresses on tubes and validating the model by using experimental data in a steady state plant operation. Then, the geometrical variables in the model were changed to study stresses on the tubes. The results revealed that the stress was not affected by the soot blowing process and the finite element model gave the results 1.24% errors from the experiment. The geometrical variables influenced the stress, with the most optimum tubes design in this research reduced the average stress from the present design 31.28%.

Keywords: boiler water wall tube, finite element, stress analysis, strain gage rosette

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Authors: Ranajay Bhowmick

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Analysis of stresses for an infinitesimal tetrahedron leads to a situation where we obtain a cubic equation consisting of three stress invariants. This cubic equation, when solved for a definite condition, gives the principal stresses directly without requiring any cumbersome and time-consuming trial and error methods or iterative numerical procedures. Since the failure criterion of different materials are generally expressed as functions of principal stresses, an attempt has been made in this study to incorporate the solutions of the cubic equation in the form of principal stresses, obtained for a definite condition, into some of the established failure theories to determine their modified descriptions. It has been observed that the failure theories can be represented using the quadratic stress invariant and the orientation of the principal plane.

Keywords: cubic equation, stress invariant, trigonometric, explicit solution, principal stress, failure criterion

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Authors: Luixa Reizabal, Inaki Garcia, Eneko Sansinenea, Ainize Sarrionandia, Karmele Lopez De Ipina, Elsa Fernandez

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Although the effects of incarceration in prisons close to prisoners’ and their families’ residences have been studied, little is known about the effects of remote incarceration. The present study shows the impact of secondary prisonization on mental health of elderly parents of Basque prisoners who are incarcerated in prisons located far away from prisoners’ and their families’ residences. Secondary prisonization refers to the effects that imprisonment of a family member has on relatives. In the study, psychological effects are analyzed by means of comparative methodology. Specifically, levels of psychopathology (depression, anxiety, and stress) and positive mental health (psychological, social, and emotional well-being) are studied in a sample of parents over 65 years old of prisoners incarcerated in prisons located a long distance away (concretely, some of them in a distance of less than 400 km, while others farther than 400 km) from the Basque Country. The dataset consists of data collected through a questionnaire and from a spontaneous speech recording. The statistical and automatic analyses show that levels of psychopathology and positive mental health of elderly parents of prisoners incarcerated in remote jails are affected by the incarceration of their sons or daughters. Concretely, these parents show higher levels of depression, anxiety, and stress and lower levels of emotional (but not psychological or social) wellbeing than parents with no imprisoned daughters or sons. These findings suggest that parents with imprisoned sons or daughters suffer the impact of secondary prisonization on their mental health. When comparing parents with sons or daughters incarcerated within 400 kilometers from home and parents whose sons or daughters are incarcerated farther than 400 kilometers from home, the latter present higher levels of psychopathology, but also higher levels of positive mental health (although the difference between the two groups is not statistically significant). These findings might be explained by resilience. In fact, in traumatic situations, people can develop a force to cope with the situation, and even present a posttraumatic growth. Bearing in mind all these findings, it could be concluded that secondary prisonization implies for elderly parents with sons or daughters incarcerated in remote jails suffering and, in consequence, that changes in the penitentiary policy applied to Basque prisoners are required in order to finish this suffering.

Keywords: automatic spontaneous speech analysis, elderly parents, machine learning, positive mental health, psychopathology, remote incarceration, secondary prisonization

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Authors: Jennifer Foss, DNP, RN-BC, NEA-BC

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Stress and burnout in the bedside registered nurse have deleterious consequences for registered nurses, patients, and the hospitals that employ them. The objective of this study was to determine whether a sixty-minute mindfulness workshop was effective in reducing perceived levels of stress and decreasing mindfulness in registered nurses working in the acute care setting. Registered nurses at a community hospital in the Northeast part of the country were recruited through e-mail and flyers in breakrooms. Participants completed the Perceived Stress Scale (PSS) and Mindfulness Attention Awareness Scale (MAAS) two weeks prior to taking part in the intervention and two weeks post intervention. Of the twenty-three registered nurses who completed the baseline questionnaires, 91% were female with an average age between 30-39 years. Sixty-five percent of subjects completed the questionnaires two weeks post intervention. Two weeks post intervention, registered nurses reported a decrease in perception of stress (pre and post PSS was .133) and was not significant (t=1.293, df=14, p=.217). Likewise, an increase in mindful attention .325 was reported two-weeks post intervention and indicated a favorable tendency to enter a mindful state. This finding was also not significant (t=-1.990, df=14, p=.066). In this study, nurses reported decreases in perceived stress and increases in mindfulness after attending a sixty-minute mindfulness workshop. Further research is needed to determine the long-term impact of mindfulness-based training on nurses' stress and mindfulness skills. The results of this study add to the body of literature that supports the benefits of mindfulness-based interventions in the healthcare setting.

Keywords: Stress, burnout, nursing, acute care nursing

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Authors: A. Gagat-Matuła

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The aim of this article is to present a relation between family relationships and styles of approach to coping with stress among young people from migrant families with cerebral palsy. The study involved 70 persons (with cerebral palsy in the standard intellectual capacity) from families, in which at least one of parents is a migrant. To measure the level of communication in the family, the Family Relationships Questionnaire (FRQ) was employed, while the styles of coping with stress was investigated with the CISS Questionnaire. The relation between family relationships and styles of coping with stressful situations of the respondents was investigated. It was shown that there is an affiliation between the emotion-oriented style of coping with the stress and the variable of “communication in my family”. Moreover, it was demonstrated that there is a linkage between the task-oriented style of coping with the stress and the variable of “maternal control in mother-child relationship”. Young people with CP subjected to overprotection and control from their mothers in problem situations tend to focus on their own emotions instead of trying to undertake constructive actions. Excessive control in daily life by mothers results in passivity and a lack of motivation to cope with difficult situations.

Keywords: young people with cerebral palsy, family relationships, styles of coping with stress, migration

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Authors: Monika Szpringer, Mariola Wojciechowska, Robert Dutkiewicz, Grażyna Nowak-Starz, Marzena Olędzka

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The main aim of this article is to determine the phenomenon of stress among academic teachers as well as to identify the extent to which the teachers experience work-related psychological risks. It is also important to support academic teachers trade unions in scope of stress-oriented activities, including psychological dangers in the assessment of risk in the workplace (college). The authors used a method of a diagnostic survey with a polling as a technique and authors’ questionnaire as a tool. The survey was conducted between September and December of 2013 and it comprised 1890 academic teachers from five voivodeships. The study reveals that 84.0% of the respondents found the work of an academic teacher to be borne with a considerable stress. The percentage values of the most frequent causes of stress are as follows: frequent changes of both organisational and didactic matters as well as overwhelming bureaucracy (77.8 %), time pressure regarding professional development and related risk of losing job (68.2 %), difficult working conditions (45.4%), conflicts and rivalry between teachers (44.1%), excessive amount of duties as well as increasing requirements and demanding attitude of students (33.7%). Work-related stress affects or significantly affects the private life of 69 % and 66.4 % of the respondents respectively. The majority of the people surveyed deals with stress by undertaking various activities, with 40% pointing at using various substances, mostly cigarettes and alcohol (p > 0,05) Physical ailments were experienced by 81% of the respondents, in 9% they were rare and 8 % of the respondents had never experienced such disorders. The entire group of the surveyed people (100 %) claimed that they have no possibility of contacting a psychologist at their workplace (p > 0.05), and they stated that the need of contacting specialists does exist.

Keywords: stress, academic teachers, psychological risks, work-related

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Authors: A. Bilek, M. Beldi, T. Cherfi, S. Djebali, S. Larbi

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Finite elements analysis and photoelasticity are used to determine the stress field developed in a double edge notched specimen loaded in tension. The specimen is cut in a birefringent plate. Experimental isochromatic fringes are obtained with circularly polarized light on the analyzer of a regular polariscope. The fringes represent the loci of points of equal maximum shear stress. In order to obtain the stress values corresponding to the fringe orders recorded in the notched specimen, particularly in the neighborhood of the notches, a calibrating disc made of the same material is loaded in compression along its diameter in order to determine the photoelastic fringe value. This fringe value is also used in the finite elements solution in order to obtain the simulated photoelastic fringes, the isochromatics as well as the isoclinics. A color scale is used by the software to represent the simulated fringes on the whole model. The stress concentration factor can be readily obtained at the notches. Good agreements are obtained between the experimental and the simulated fringe patterns and between the graphs of the shear stress particularly in the neighborhood of the notches. The purpose in this paper is to show that one can obtain rapidly and accurately, by the finite element analysis, the isochromatic and the isoclinic fringe patterns in a stressed model as the experimental procedure can be time consuming. Stress fields can therefore be analyzed in three dimensional models as long as the meshing and the limit conditions are properly set in the program.

Keywords: isochromatic fringe, isoclinic fringe, photoelasticity, stress concentration factor

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Authors: Aruha Khan, Brynn E. Kankel, Paraskevi Papadopoulou

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In recent years, extensive research upon ‘stress’ has provided insight into its two distinct guises, namely the short–term (fight–or–flight) response versus the long–term (chronic) response. Specifically, the long–term or chronic response is associated with the suppression or dysregulation of immune function. It is also widely noted that the occurrence of cancer is greatly correlated to the suppression of the immune system. It is thus necessary to explore the impact of long–term or chronic stress upon the prevalence and risk of cancer. To what extent can the dysregulation of immune function caused by long–term exposure to stress be controlled or minimized? This study focuses explicitly upon immunosuppression due to its ability to increase disease susceptibility, including cancer itself. Based upon an analysis of the literature relating to the fundamental structure of the immune system alongside the prospective linkage of chronic stress and the development of cancer, immunosuppression may not necessarily correlate directly to the acquisition of cancer—although it remains a contributing factor. A cross-sectional analysis of the survey data from the University of Tennessee Medical Center (UTMC) and Harvard Medical School (HMS) will provide additional supporting evidence (or otherwise) for the hypothesis of the study about whether immunosuppression (caused by the chronic stress response) notably impacts the prevalence of cancer. Finally, a multidimensional framework related to education on chronic stress and its effects is proposed.

Keywords: immune system, immunosuppression, long–term (chronic) stress, risk of cancer

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Authors: Deepak Bhardwaj, Narendra Tuteja

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Global climate change is impacting large agrarian societies, especially those in countries located near the equator. Agriculture, and consequently, plant-based food, is the hardest hit in tropical and sub-tropical countries such as India due to an increased incidence of drought as well as an increase in soil salinity. One method that holds promise is AMF-rich biofertilizers which assist in activating proteins which in turn help alleviate abiotic stress in plants. In the present study, we identified two important species of (arbuscular mycorrhizal fungus) AMF belonging to Glomus and Gigaspora from the rhizosphere of the important medicinal plant Justicia adathoda. These two species have been found to be responsible for the abundance of Justicia adathoda in the semi-arid areas of the Jammu valley located in northern India, namely, the Union Territory of Jammu and Kashmir. We isolated the species of Glomus and Gigaspora from the rhizosphere of Justicia adathoda and used them as biofertilizers for the tomato plant. Significant improvements in the growth parameters were observed in the tomato plants inoculated with Glomus sp. and Gigaspora sp. in comparison with the tomato plants that were grown without AMF treatments. Tomato plants grown along with Glomus sp. and Gigaspora sp. have been observed to withstand 200 mM of salinity and 25% PEG stress. AMF also resulted in an increased concentration of proline and antioxidant enzymes in tomato plants. We also examined the expression levels of salinity and drought stress-inducible genes such as pea DNA helicase 45 (PDH 45) and genes of G-protein subunits of the tomato plants inoculated with and without AMF under stress and normal conditions. All the stress-inducible genes showed a significant increase in their gene expression under stress and AMF inoculation, while their levels were found to be normal under AMF inoculation without stress. We propose a model of abiotic stress alleviation in tomato plants with the help of external factors such as AMF and internally with the help of proteins like PDH 45 and G-proteins.

Keywords: AMF, abiotic stress, g-proteins, PDH-45

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Authors: Zemour Kamel, Chouhim Kadda Mohamed Amine

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Salinity is one of the most environmental factors limiting crop productivity. It has a negative effect on both germination and plant growth processes (photosynthesis, respiration, and transpiration), nutrient balance, membrane properties and cellular homeostasis, enzymatic and metabolic activities. Among the strategic crops in the world and more mainly in Algeria, durum wheat is very affected by this abiotic stress. For that, this study focuses on an evaluation of salt stress effect on the germination process of durum wheat as well as its response after application of lavender hydrosol and aqueous pistachio extract. The results have shown that all the physicochemical parameters of germination have been affected by this stress. However, lavender hydrosol and aqueous pistachio extract, considered as organic compounds, significantly improved the germination of wheat seeds. Finally, this study has highlighted the importance of using organic products as an ideal alternative to reduce the effect of abiotic stress on durum wheat productivity.

Keywords: salinity, wheat durum, extract, lavender hydrosol, aqueous pistachio

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Authors: V. Hashim, P. N. Dileep

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Stent implantation is being seen as the most successful method to treat coronary artery diseases. Different types of stents are available in the market these days and the success of a stent implantation greatly depends on the proper selection of a suitable stent for a patient. Computer numerical simulation is the cost effective way to choose the compatible stent. Studies confirm that the design characteristics of stent do have great importance with regards to the pressure it can sustain, the maximum displacement it can produce, the developed stress concentration and so on. In this paper different designs of stent were analyzed together with balloon to optimize the stent and balloon system. Commercially available stent Palmaz-Schatz has been selected for analysis. Abaqus software is used to simulate the system. This work is the finite element analysis of the artery stent implant to find out the design factors affecting the stress and strain. The work consists of two phases. In the first phase, stress distribution of three models were compared - stent without balloon, stent with balloon of equal length and stent with balloon of extra length than stent. In second phase, three different design models of Palmaz-Schatz stent were compared by keeping the balloon length constant. The results obtained from analysis shows that, the design of the strut have strong effect on the stress distribution. A design with chamfered slots found better results. The length of the balloon also has influence on stress concentration of the stent. Increase in length of the balloon will reduce stress, but will increase dog boning effect.

Keywords: coronary stent, finite element analysis, restenosis, stress concentration

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Authors: Mary Esere, Mogbekeloluwa Fakokunde, Adetoun Idowu

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Background: Working in a military setting could elicit some amount of stressful doses into ones system because of the attendant peculiar characteristics found in the military environment. Thus, this study was carried out to find out the sources of occupational stress among teachers in various Command Secondary Schools within 2 Division of Nigerian Army. Method: The study employed a survey method. Simple random sampling technique was used to select the schools in the Division. A total of 200 respondents participated in the study. Sources of Teachers’ Occupational Stress Questionnaire (STOSQ) was administered to the respondents to collect relevant data. The t-test and Analysis of Variance (ANOVA) statistics were used to test the hypotheses. Findings: From the study, it was discovered that teachers in this setting do experience occupational stress. Their major sources of stress bother on issues relating to salaries and allowances and staff welfare concerns. The findings also revealed that there were no significant differences in the sources of occupational stress among the teachers in respect to gender and marital status. Discussion: Based on these findings, it was recommended that the Appropriate Superior Authority (ASA) should reconstitute the proscribed Armed Forces Schools Management Board (AFSMB) where issues, such as staff salaries and welfare concerns for teachers working in the schools under the three services (Army, Navy, Airforce) will always be addressed. This will go a long way in enhancing the psychological well-being of the teachers.

Keywords: Nigerian army, occupational stress, sources, teachers

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Authors: Regina Bowler

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Rationale & Aims: Complementary interventions such as mindfulness-meditation, gratitude, and self-affirmation are often used by therapists to treat stress. Many studies have been conducted using these interventions either individually or adjunctively with regard to stress. However, there has been little work comparing these interventions to investigate which of them is the most effective in treating stress. This study aims to compare these interventions and to determine which of them has the strongest perceived and physiological impact on stress. Participants: 120 law students preparing to take the bar exam: 3 experimental groups of 30 individuals, 1 control group of 30 individuals. Methods: One day prior to administering the interventions, baseline salivary cortisol samples will be taken, and the participants will complete the perceived stress scale (Cohen et al., 1983). Thirty days prior to the bar exam, each experimental group will be given an intervention to practice. Interventions will be practiced once in the morning after waking and once at night at bedtime. In group one, each participant will do a recorded three-minute mindfulness meditation. In group two, each participant will practice gratitude by writing down three things he/she/they are grateful for. In group three, each participant will practice affirmation by writing three sentences affirming his/her/their core values. The control group will not have an intervention to practice. Starting experimental day 1, upon waking and prior to practicing the intervention, the participants will take a salivary cortisol sample. Then they will practice their given intervention. Every night, before going to bed, the participants will practice their given intervention for a second time. The participants will practice their interventions and take salivary cortisol samples for 28 days. After each seven-day period (days 7, 14, 21, 28), the participants will fill out a brief questionnaire about the effects their intervention has on their stress, daily life, and relationships with themselves and others. On day 29, the participants will take a final salivary cortisol sample and will fill out the Perceived Stress Scale (Cohen et al., 1983). Applications of findings: Findings from this study would inform therapists of best practices when working with clients with stress. Moreover, therapists will gain knowledge of how individuals perceive these interventions and their impact on stress, daily life, somatic symptoms, and relationships with self and others. Thus, therapists will be able to administer these interventions with more precision to the stress-related contexts and issues their clients bring.

Keywords: stress, mindfulness-meditation, gratitude, affirmations, complementary interventions

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