Search results for: professional stress
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5595

Search results for: professional stress

4995 Dynamics Analyses of Swing Structure Subject to Rotational Forces

Authors: Buntheng Chhorn, WooYoung Jung

Abstract:

Large-scale swing has been used in entertainment and performance, especially in circus, for a very long time. To increase the safety of this type of structure, a thorough analysis for displacement and bearing stress was performed for an extreme condition where a full cycle swing occurs. Different masses, ranging from 40 kg to 220 kg, and velocities were applied on the swing. Then, based on the solution of differential dynamics equation, swing velocity response to harmonic force was obtained. Moreover, the resistance capacity was estimated based on ACI steel structure design guide. Subsequently, numerical analysis was performed in ABAQUS to obtain the stress on each frame of the swing. Finally, the analysis shows that the expansion of swing structure frame section was required for mass bigger than 150kg.

Keywords: swing structure, displacement, bearing stress, dynamic loads response, finite element analysis

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4994 NextCovps: Design and Stress Analysis of Dome Composite Overwrapped Pressure Vessels using Geodesic Trajectory Approach

Authors: Ammar Maziz, Prateek Gupta, Thiago Vasconcellos Birro, Benoit Gely

Abstract:

Hydrogen as a sustainable fuel has the highest energy density per mass as compared to conventional non-renewable sources. As the world looks to move towards sustainability, especially in the sectors of aviation and automotive, it becomes important to address the issue of storage of hydrogen as compressed gas in high-pressure tanks. To improve the design for the efficient storage and transportation of Hydrogen, this paper presents the design and stress analysis of Dome Composite Overwrapped Pressure Vessels (COPVs) using the geodesic trajectory approach. The geodesic trajectory approach is used to optimize the dome design, resulting in a lightweight and efficient structure. Python scripting is employed to implement the mathematical modeling of the COPV, and after validating the model by comparison to the published paper, stress analysis is conducted using Abaqus commercial code. The results demonstrate the effectiveness of the geodesic trajectory approach in achieving a lightweight and structurally sound dome design, as well as the accuracy and reliability of the stress analysis using Abaqus commercial code. This study provides insights into the design and analysis of COPVs for aerospace applications, with the potential for further optimization and application in other industries.

Keywords: composite overwrapped pressure vessels, carbon fiber, geodesic trajectory approach, dome design, stress analysis, plugin python

Procedia PDF Downloads 75
4993 Numerical Analysis on the Effect of Abrasive Parameters on Wall Shear Stress and Jet Exit Kinetic Energy

Authors: D. Deepak, N. Yagnesh Sharma

Abstract:

Abrasive Water Jet (AWJ) machining is a relatively new nontraditional machine tool used in machining of fiber reinforced composite. The quality of machined surface depends on jet exit kinetic energy which depends on various operating and material parameters. In the present work the effect abrasive parameters such as its size, concentration and type on jet kinetic energy is investigated using computational fluid dynamics (CFD). In addition, the effect of these parameters on wall shear stress developed inside the nozzle is also investigated. It is found that for the same operating parameters, increase in the abrasive volume fraction (concentration) results in significant decrease in the wall shear stress as well as the jet exit kinetic energy. Increase in the abrasive particle size results in marginal decrease in the jet exit kinetic energy. Numerical simulation also indicates that garnet abrasives produce better jet exit kinetic energy than aluminium oxide and silicon carbide.

Keywords: abrasive water jet machining, jet kinetic energy, operating pressure, wall shear stress, Garnet abrasive

Procedia PDF Downloads 364
4992 Influence of the Granular Mixture Properties on the Rheological Properties of Concrete: Yield Stress Determination Using Modified Chateau et al. Model

Authors: Rachid Zentar, Mokrane Bala, Pascal Boustingorry

Abstract:

The prediction of the rheological behavior of concrete is at the center of current concerns of the concrete industry for different reasons. The shortage of good quality standard materials combined with variable properties of available materials imposes to improve existing models to take into account these variations at the design stage of concrete. The main reasons for improving the predictive models are, of course, saving time and cost at the design stage as well as to optimize concrete performances. In this study, we will highlight the different properties of the granular mixtures that affect the rheological properties of concrete. Our objective is to identify the intrinsic parameters of the aggregates which make it possible to predict the yield stress of concrete. The work was done using two typologies of grains: crushed and rolled aggregates. The experimental results have shown that the rheology of concrete is improved by increasing the packing density of the granular mixture using rolled aggregates. The experimental program realized allowed to model the yield stress of concrete by a modified model of Chateau et al. through a dimensionless parameter following Krieger-Dougherty law. The modelling confirms that the yield stress of concrete depends not only on the properties of cement paste but also on the packing density of the granular skeleton and the shape of grains.

Keywords: crushed aggregates, intrinsic viscosity, packing density, rolled aggregates, slump, yield stress of concrete

Procedia PDF Downloads 110
4991 How Technology Can Help Teachers in Reflective Practice

Authors: Ambika Perisamy, Asyriawati binte Mohd Hamzah

Abstract:

The focus of this presentation is to discuss teacher professional development (TPD) through the use of technology. TPD is necessary to prepare teachers for future challenges they will face throughout their careers and to develop new skills and good teaching practices. We will also be discussing current issues in embracing technology in the field of early childhood education and the impact on the professional development of teachers. Participants will also learn to apply teaching and learning practices through the use of technology. One major objective of this presentation is to coherently fuse practical, technology and theoretical content. The process begins by concretizing a set of preconceived ideas which need to be joined with theoretical justifications found in the literature. Technology can make observations fairer and more reliable, easier to implement, and more preferable to teachers and principals. Technology will also help principals to improve classroom observations of teachers and ultimately improve teachers’ continuous professional development. Video technology allows the early childhood teachers to record and keep the recorded video for reflection at any time. This will also provide opportunities for her to share with her principals for professional dialogues and continuous professional development plans. A total of 10 early childhood teachers and 4 principals were involved in these efforts which identified and analyze the gaps in the quality of classroom observations and its co relation to developing teachers as reflective practitioners. The methodology used involves active exploration with video technology recordings, conversations, interviews and authentic teacher child interactions which forms the key thrust in improving teaching and learning practice. A qualitative analysis of photographs, videos, transcripts which illustrates teacher’s reflections and classroom observation checklists before and after the use of video technology were adopted. Arguably, although PD support can be magnanimously strong, if teachers could not connect or create meaning out of the opportunities made available to them, they may remain passive or uninvolved. Therefore, teachers must see the value of applying new ideas such as technology and approaches to practice while creating personal meaning out of professional development. These video recordings are transferable, can be shared and edited through social media, emails and common storage between teachers and principals. To conclude the importance of reflective practice among early childhood teachers and addressing the concerns raised before and after the use of video technology, teachers and principals shared the feasibility, practical and relevance use of video technology.

Keywords: early childhood education, reflective, improve teaching and learning, technology

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4990 Addiction Counseling Resources: A Qualitative Study

Authors: Cailyn Green

Abstract:

Substance use counselors have a variety of fast-paced tasks and responsibilities. Professional resources are designed to support professionals in making their job duties easier and less stressful. The purpose of this research was to identify what types of resources would support addiction counselors in performing their job duties. Counselors often must jump in and facilitate a group counseling session with little to no time for prep. This causes stress and creates pressure to come up with a clinical group activity in little time. The researcher utilized qualitative interviews focused on identifying what types of resources would support addiction counselors in doing their jobs easier and effectively. The researcher visited 23 different addiction counseling facilities seeking participants for the interviews. Altogether 15 interviews were collected across six different substance-use counseling facilities. The interviews guided the researcher toward creating an open education resource (OER) of group activities for addiction counselors to utilize.

Keywords: addiction, counseling, resources, OER, treatment

Procedia PDF Downloads 63
4989 Seismic Safety Evaluation of Weir Structures Using the Finite and Infinite Element Method

Authors: Ho Young Son, Bu Seog Ju, Woo Young Jung

Abstract:

This study presents the seismic safety evaluation of weir structure subjected to strong earthquake ground motions, as a flood defense structure in civil engineering structures. The seismic safety analysis procedure was illustrated through development of Finite Element (FE) and InFinite Element (IFE) method in ABAQUS platform. The IFE model was generated by CINPS4, 4-node linear one-way infinite model as a sold continuum infinite element in foundation areas of the weir structure and then nonlinear FE model using friction model for soil-structure interactions was applied in this study. In order to understand the complex behavior of weir structures, nonlinear time history analysis was carried out. Consequently, it was interesting to note that the compressive stress gave more vulnerability to the weir structure, in comparison to the tensile stress, during an earthquake. The stress concentration of the weir structure was shown at the connection area between the weir body and stilling basin area. The stress both tension and compression was reduced in IFE model rather than FE model of weir structures.

Keywords: seismic, numerical analysis, FEM, weir, boundary condition

Procedia PDF Downloads 436
4988 Examining Electroencephalographic Activity Differences Between Goalkeepers and Forwards in Professional Football Players

Authors: Ruhollah Basatnia, Ali Reza Aghababa, Mehrdad Anbarian, Sara Akbari, Mohammad Khazaee

Abstract:

Introduction: The investigation of brain activity in sports has become a subject of interest for researchers. Several studies have examined the patterns or differences in brain activity during different sports situations. Previous studies have suggested that the pattern of cortical activity may differ between different football positions, such as goalkeepers and other players. This study aims to investigate the differences in electroencephalographic (EEG) activity between the positions of goalkeeper and forward in professional football players. Methods: Fourteen goalkeepers and twelve forwards, all males between 19-28 years old, participated in the study. EEG activity was recorded while participants were sitting with their eyes closed for 5 minutes. The mean relative power of EEG activity for each frequency band was compared between the two groups using independent samples t-test. Findings: The study found significant differences in the relative power of EEG activity between different frequency bands and electrodes. Notably, significant differences were observed in the mean relative power of EEG activity between the two groups for certain frequency bands and electrodes. These findings suggest that EEG activity can serve as a sensory indicator for cognitive and performance differences between goalkeepers and forwards in football players. Discussion: The results of this study suggest that EEG activity can be used to identify cognitive and performance differences between goalkeepers and forwards in football players. However, further research is needed to establish the relationship between EEG activity and actual performance in the field. Future studies should investigate the potential influence of other factors, such as fatigue and stress, on the EEG activity of football players. Additionally, the use of real-time EEG feedback could be explored as a tool for training and performance optimization in football players. Further research is required to fully understand the potential of EEG activity as a sensory indicator for cognitive and performance differences between football player positions and to explore its potential applications for training and performance optimization in football and other sports.

Keywords: football, brain activity, EEG, goalkeepers, forwards

Procedia PDF Downloads 65
4987 A Structural Constitutive Model for Viscoelastic Rheological Behavior of Human Saphenous Vein Using Experimental Assays

Authors: Rassoli Aisa, Abrishami Movahhed Arezu, Faturaee Nasser, Seddighi Amir Saeed, Shafigh Mohammad

Abstract:

Cardiovascular diseases are one of the most common causes of mortality in developed countries. Coronary artery abnormalities and carotid artery stenosis, also known as silent death, are among these diseases. One of the treatment methods for these diseases is to create a deviatory pathway to conduct blood into the heart through a bypass surgery. The saphenous vein is usually used in this surgery to create the deviatory pathway. Unfortunately, a re-surgery will be necessary after some years due to ignoring the disagreement of mechanical properties of graft tissue and/or applied prostheses with those of host tissue. The objective of the present study is to clarify the viscoelastic behavior of human saphenous tissue. The stress relaxation tests in circumferential and longitudinal direction were done in this vein by exerting 20% and 50% strains. Considering the stress relaxation curves obtained from stress relaxation tests and the coefficients of the standard solid model, it was demonstrated that the saphenous vein has a non-linear viscoelastic behavior. Thereafter, the fitting with Fung’s quasilinear viscoelastic (QLV) model was performed based on stress relaxation time curves. Finally, the coefficients of Fung’s QLV model, which models the behavior of saphenous tissue very well, were presented.

Keywords: Viscoelastic behavior, stress relaxation test, uniaxial tensile test, Fung’s quasilinear viscoelastic (QLV) model, strain rate

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4986 Effects of a School-Based Mindfulness Intervention on Stress and Emotions on Students Enrolled in an Independent School

Authors: Tracie Catlett

Abstract:

Students enrolled in high-achieving schools are under tremendous pressure to perform at high levels inside and outside the classroom. Achievement pressure is a prevalent source of stress for students enrolled in high-achieving schools, and female students in particular experience a higher frequency and higher levels of stress compared to their male peers. The practice of mindfulness in a school setting is one tool that has been linked to improved self-regulation of emotions, increased positive emotions, and stress reduction. A mixed methods randomized pretest-posttest no-treatment control trial, evaluated the effects of a six-session mindfulness intervention taught during a regularly scheduled life skills period in an independent day school, one type of high-achieving school. Twenty-nine students in Grades 10 and 11 were randomized by class where Grade 11 students were in the intervention group (n = 14) and Grade 10 students were in the control group (n = 15). Findings from the study produced mixed results. There was no evidence that the mindfulness program reduced participants’ stress levels and negative emotions. In fact, contrary to what was expected, students enrolled in the intervention group experienced higher levels of stress and increased negative emotions at posttreatment when compared to pretreatment. Neither the within-group nor the between-groups changes in stress level were statistically significant, p > .05, and the between-groups effect size was small, d = .2. The study found evidence that the mindfulness program may have had a positive impact on students’ ability to regulate their emotions. The within-group comparison and the between-groups comparison at posttreatment found that students in the mindfulness course experienced statistically significant improvement in the in their ability to regulate their emotions at posttreatment, p = .009 < .05 and p =. 034 < .05, respectively. The between-groups effect size was medium, d =.7, suggesting that the positive differences in emotion regulation difficulties were substantial and have practical implications. The analysis of gender differences as they relate to stress and emotions revealed that female students perceive higher levels of stress and report experiencing stress more often than males. There were no gender differences when analyzing sources of stress experienced by the student participants. Both females and males experience regular achievement pressures related to their school performance and worry about their future, college acceptance, grades, and parental expectations. Females reported an increased awareness of their stress and actively engaged in practicing mindfulness to manage their stress. Students in the treatment group expressed that the practice of mindfulness resulted in feelings of relaxation and calmness.

Keywords: achievement pressure, adolescents, emotion regulation, emotions, high-achieving schools, independent schools, mindfulness, negative affect, positive affect, stress

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4985 Preliminary Study of Human Reliability of Control in Case of Fire Based on the Decision Processes and Stress Model of Human in a Fire

Authors: Seung-Un Chae, Heung-Yul Kim, Sa-Kil Kim

Abstract:

This paper presents the findings of preliminary study on human control performance in case of fire. The relationship between human control and human decision is studied in decision processes and stress model of human in a fire. Human behavior aspects involved in the decision process during a fire incident. The decision processes appear that six of individual perceptual processes: recognition, validation, definition, evaluation, commitment, and reassessment. Then, human may be stressed in order to get an optimal decision for their activity. This paper explores problems in human control processes and stresses in a catastrophic situation. Thus, the future approach will be concerned to reduce stresses and ambiguous irrelevant information.

Keywords: human reliability, decision processes, stress model, fire

Procedia PDF Downloads 969
4984 Effects of a Simulated Power Cut in Automatic Milking Systems on Dairy Cows Heart Activity

Authors: Anja Gräff, Stefan Holzer, Manfred Höld, Jörn Stumpenhausen, Heinz Bernhardt

Abstract:

In view of the increasing quantity of 'green energy' from renewable raw materials and photovoltaic facilities, it is quite conceivable that power supply variations may occur, so that constantly working machines like automatic milking systems (AMS) may break down temporarily. The usage of farm-made energy is steadily increasing in order to keep energy costs as low as possible. As a result, power cuts are likely to happen more frequently. Current work in the framework of the project 'stable 4.0' focuses on possible stress reactions by simulating power cuts up to four hours in dairy farms. Based on heart activity it should be found out whether stress on dairy cows increases under these circumstances. In order to simulate a power cut, 12 random cows out of 2 herds were not admitted to the AMS for at least two hours on three consecutive days. The heart rates of the cows were measured and the collected data evaluated with HRV Program Kubios Version 2.1 on the basis of eight parameters (HR, RMSSD, pNN50, SD1, SD2, LF, HF and LF/HF). Furthermore, stress reactions were examined closely via video analysis, milk yield, ruminant activity, pedometer and measurements of cortisol metabolites. Concluding it turned out, that during the test only some animals were suffering from minor stress symptoms, when they tried to get into the AMS at their regular milking time, but couldn´t be milked because the system was manipulated. However, the stress level during a regular “time-dependent milking rejection” was just as high. So the study comes to the conclusion, that the low psychological stress level in the case of a 2-4 hours failure of an AMS does not have any impact on animal welfare and health.

Keywords: dairy cow, heart activity, power cut, stable 4.0

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4983 Making Lightweight Concrete with Meerschaum

Authors: H. Gonen, M. Dogan

Abstract:

Meerschaum, which is found in the earth’s crust, is a white and clay like hydrous magnesium silicate. It has a wide area of use from production of carious ornaments to chemical industry. It has a white and irregular crystalline structure. It is wet and moist when extracted, which is a good form for processing. At drying phase, it gradually loses its moisture and becomes lighter and harder. In through-dry state, meerschaum is durable and floats on the water. After processing of meerschaum, A ratio between %15 to %40 of the amount becomes waste. This waste is usually kept in a dry-atmosphere which is isolated from environmental effects so that to be used right away when needed. In this study, use of meerschaum waste as aggregate in lightweight concrete is studied. Stress-strain diagrams for concrete with meerschaum aggregate are obtained. Then, stress-strain diagrams of lightweight concrete and concrete with regular aggregate are compared. It is concluded that meerschaum waste can be used in production of lightweight concrete.

Keywords: lightweight concrete, meerschaum, aggregate, sepiolite, stress-strain diagram

Procedia PDF Downloads 585
4982 Expression of Micro-RNA268 in Zinc Deficient Rice

Authors: Sobia Shafqat, Saeed Ahmad Qaisrani

Abstract:

MicroRNAs play an essential role in the regulation and development of all processes in most eukaryotes because of their prospective part as mediators controlling cell growth and differentiation towards the exact position of RNAs response in plants under biotic and abiotic factors or stressors. In a few cases, Zn is oblivious poisonous for plants due to its heavy metal status. Some other metals are extremely toxic, like Cd, Hg, and Pb, but these elements require in rice for the programming of genes under abiotic stress resembling Zn stress when micro RNAs268 was importantly introduced in rice. The micro RNAs overexpressed in transgenic plants with an accumulation of a large amount of melanin dialdehyde, hydrogen peroxide, and an excessive quantity of Zn in the seedlings stage. Let out results for rice pliability under Zn stress micro RNAs act as negative controllers. But the role of micro RNA268 act as a modulator in different ecological condition. It has been explained clearly with a long understanding of the role of micro RNA268 under stress conditions; pliability and practically showed outcome to increase plant sufferance under Zn stress because micro RNAs is an intervention technique for gene regulation in gene expression. The proposed study was experimented with by using genetic factors of Zn stress and toxicity effect on rice plants done at District Vehari, Pakistan. The trial was performed randomly with three replications in a complete block design (RCBD). These blocks were controlled with different concentrations of genetic factors. By overexpression of micro RNA268 rice, seedling growth was not stopped under Zn deficiency due to the accumulation of a large amount of melanin dialdehyde, hydrogen peroxide, and an excessive quantity of Zn in their seedlings. Results showed that micro RNA268 act as a negative controller under Zn stress. In the end, under stress conditions, micro RNA268 showed the necessary function in the tolerance of rice plants. The directorial work sketch gave out high agronomic applications and yield outcomes in rice with a specific amount of Zn application.

Keywords: micro RNA268, zinc, rice, agronomic approach

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4981 The Use of Actoprotectors by Professional Athletes

Authors: Kalin Ivanov, Stanislava Ivanova

Abstract:

Actoprotectors are substances with hight performance enchasing potential and hight antioxidant activity. Most of these drugs have been developed in USSR for military medicine purposes. Based on their chemical composition actoprotectors could be classified into three categories: benzimidazole derivatives (ethomersol, bemitil); adamantane derivatives (bromantane), other chemical classes. First data for intake of actoprotectors from professional athletes is from 1980. The daily intake of actoprotectors demonstrate many benefits for athletes like: positive effect on the efficiency of physical work, antihypoxic effects, antioxidant effects, nootropic effects, rapid recovery. Since 1997, bromantane is considered as doping. This is a result of Summer Olympic Games in Athlanta (1996) when several Russian athletes tested positive for bramantane. Even the drug is safe for athletes health its use is considered as violation of anti- doping rules. More than 37 years bemetil has been used by professional athletes with no risk but currently it is included in WADA monitoring programme for 2018. Current perspectives are that most used actoprotectors would be considered as doping. Many clinical studies have confirmed that intake of bemitil and bromantan demonstrate positive influence on the physical work capacity but data for other actoprotectors like chlodantane, ademol, ethomersol is limited.

Keywords: actoprotector, sport, doping, bemitil

Procedia PDF Downloads 299
4980 Inversion of PROSPECT+SAIL Model for Estimating Vegetation Parameters from Hyperspectral Measurements with Application to Drought-Induced Impacts Detection

Authors: Bagher Bayat, Wouter Verhoef, Behnaz Arabi, Christiaan Van der Tol

Abstract:

The aim of this study was to follow the canopy reflectance patterns in response to soil water deficit and to detect trends of changes in biophysical and biochemical parameters of grass (Poa pratensis species). We used visual interpretation, imaging spectroscopy and radiative transfer model inversion to monitor the gradual manifestation of water stress effects in a laboratory setting. Plots of 21 cm x 14.5 cm surface area with Poa pratensis plants that formed a closed canopy were subjected to water stress for 50 days. In a regular weekly schedule, canopy reflectance was measured. In addition, Leaf Area Index (LAI), Chlorophyll (a+b) content (Cab) and Leaf Water Content (Cw) were measured at regular time intervals. The 1-D bidirectional canopy reflectance model SAIL, coupled with the leaf optical properties model PROSPECT, was inverted using hyperspectral measurements by means of an iterative optimization method to retrieve vegetation biophysical and biochemical parameters. The relationships between retrieved LAI, Cab, Cw, and Cs (Senescent material) with soil moisture content were established in two separated groups; stress and non-stressed. To differentiate the water stress condition from the non-stressed condition, a threshold was defined that was based on the laboratory produced Soil Water Characteristic (SWC) curve. All parameters retrieved by model inversion using canopy spectral data showed good correlation with soil water content in the water stress condition. These parameters co-varied with soil moisture content under the stress condition (Chl: R2= 0.91, Cw: R2= 0.97, Cs: R2= 0.88 and LAI: R2=0.48) at the canopy level. To validate the results, the relationship between vegetation parameters that were measured in the laboratory and soil moisture content was established. The results were totally in agreement with the modeling outputs and confirmed the results produced by radiative transfer model inversion and spectroscopy. Since water stress changes all parts of the spectrum, we concluded that analysis of the reflectance spectrum in the VIS-NIR-MIR region is a promising tool for monitoring water stress impacts on vegetation.

Keywords: hyperspectral remote sensing, model inversion, vegetation responses, water stress

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4979 Biostimulant Activity of Chitooligomers: Effect of Different Degrees of Acetylation and Polymerization on Wheat Seedlings under Salt Stress

Authors: Xiaoqian Zhang, Ping Zou, Pengcheng Li

Abstract:

Salt stress is one of the most serious abiotic stresses, and it can lead to the reduction of agricultural productivity. High salt concentration makes it more difficult for roots to absorb water and disturbs the homeostasis of cellular ions resulting in osmotic stress, ion toxicity and generation of reactive oxygen species (ROS). Compared with the normal physiological conditions, salt stress could inhibit the photosynthesis, break metabolic balance and damage cellular structures, and ultimately results in the reduction of crop yield. Therefore it is vital to develop practical methods for improving the salt tolerance of plants. Chitooligomers (COS) is partially depolymerized products of chitosan, which is consisted of D-glucosamine and N-acetyl-D-glucosamine. In agriculture, COS has the ability to promote plant growth and induce plant innate immunity. The bioactivity of COS closely related to its degree of polymerization (DP) and acetylation (DA). However, most of the previous reports fail to mention the function of COS with different DP and DAs in improving the capacity of plants against salt stress. Accordingly, in this study, chitooligomers (COS) with different degrees of DAs were used to test wheat seedlings response to salt stress. In addition, the determined degrees of polymerization (DPs) COS(DP 4-12) and a heterogeneous COS mixture were applied to explore the relationship between the DP of COSs and its effect on the growth of wheat seedlings in response to salt stress. It showed that COSs, the exogenous elicitor, could promote the growth of wheat seedling, reduce the malondialdehyde (MDA) concentration, and increase the activities of antioxidant enzymes. The results of mRNA expression level test for salt stress-responsive genes indicated that COS keep plants away from being hurt by the salt stress via the regulation of the concentration and the increased antioxidant enzymes activities. Moreover, it was found that the activities of COS was closely related to its Das and COS (DA: 50%) displayed the best salt resistance activity to wheat seedlings. The results also showed that COS with different DP could promote the growth of wheat seedlings under salt stress. COS with a DP (6-8) showed better activities than the other tested samples, implied its activity had a close relationship with its DP. After treatment with chitohexaose, chitoheptaose, and chitooctaose, the photosynthetic parameters were improved obviously. The soluble sugar and proline contents were improved by 26.7%-53.3% and 43.6.0%-70.2%, respectively, while the concentration of malondialdehyde (MDA) was reduced by 36.8% - 49.6%. In addition, the antioxidant enzymes activities were clearly activated. At the molecular level, the results revealed that they could obviously induce the expression of Na+/H+ antiporter genes. In general, these results were fundamental to the study of action mechanism of COS on promoting plant growth under salt stress and the preparation of plant growth regulator.

Keywords: chitooligomers (COS), degree of polymerization (DP), degree of acetylation (DA), salt stress

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4978 Influence of Plant Cover and Redistributing Rainfall on Green Roof Retention and Plant Drought Stress

Authors: Lubaina Soni, Claire Farrell, Christopher Szota, Tim D. Fletcher

Abstract:

Green roofs are a promising engineered ecosystem for reducing stormwater runoff and restoring vegetation cover in cities. Plants can contribute to rainfall retention by rapidly depleting water in the substrate; however, this increases the risk of plant drought stress. Green roof configurations, therefore, need to provide plants the opportunity to efficiently deplete the substrate but also avoid severe drought stress. This study used green roof modules placed in a rainout shelter during a six-month rainfall regime simulated in Melbourne, Australia. Rainfall was applied equally with an overhead irrigation system on each module. Aside from rainfall, modules were under natural climatic conditions, including temperature, wind, and radiation. A single species, Ficinia nodosa, was planted with five different treatments and three replicates of each treatment. In this experiment, we tested the impact of three plant cover treatments (0%, 50% and 100%) on rainfall retention and plant drought stress. We also installed two runoff zone treatments covering 50% of the substrate surface for additional modules with 0% and 50% plant cover to determine whether directing rainfall resources towards plant roots would reduce drought stress without impacting rainfall retention. The retention performance for the simulated rainfall events was measured, quantifying all components for hydrological performance and survival on green roofs. We found that evapotranspiration and rainfall retention were similar for modules with 50% and 100% plant cover. However, modules with 100% plant cover showed significantly higher plant drought stress. Therefore, planting at a lower cover/density reduced plant drought stress without jeopardizing rainfall retention performance. Installing runoff zones marginally reduced evapotranspiration and rainfall retention, but by approximately the same amount for modules with 0% and 50% plant cover. This indicates that reduced evaporation due to the installation of the runoff zones likely contributed to reduced evapotranspiration and rainfall retention. Further, runoff occurred from modules with runoff zones faster than those without, indicating that we created a faster pathway for water to enter and leave the substrate, which also likely contributed to lower overall evapotranspiration and retention. However, despite some loss in retention performance, modules with 50% plant cover installed with runoff zones showed significantly lower drought stress in plants compared to those without runoff zones. Overall, we suggest that reducing plant cover represents a simple means of optimizing green roof performance but creating runoff zones may reduce plant drought stress at the cost of reduced rainfall retention.

Keywords: green roof, plant cover, plant drought stress, rainfall retention

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4977 Exploring the Relationship among Job Stress, Travel Constraints, and Job Satisfaction of the Employees in Casino Hotels: The Case of Macau

Authors: Tao Zhang

Abstract:

Job stress appears nearly everywhere especially in the hospitality industry because employees in this industry usually have to work long time and try to meet conflicting demands of their customers, managers, and company. To reduce job stress, employees of casino hotels try to perform leisure activities or tourism. However, casino employees often meet many obstacles or constraints when they plan to travel. Until now, there is little understanding as to why casino hotel employees often face many travel constraints or leisure barriers. What is more, few studies explore the relationship between travel constraints and job stress of casino employees. Therefore, this study is to explore the construct of casino hotel employees' travel constraints and the relationship among job stress, travel constraints, and job satisfaction. Using convenient sampling method, this study planned to investigate 500 front line employees and managers of ten casino hotels in Macau. A total of 500 questionnaires were distributed, and 414 valid questionnaires were received. The return rate of valid questionnaires is 82.8%. Several statistical techniques such as factor analysis, t-test, one-way ANOVA, and regression analysis were applied to analyze the collected data. The findings of this study are as follows. Firstly, by using factor analysis, this study found the travel constraints of casino employees include intrapersonal constraints, interpersonal constraints, and structural constraints. Secondly, by using regression analysis, the study found travel constraints are positively related with job stress while negatively related with job satisfaction. This means reducing travel constraints may create a chance for casino employees to travel so that they could reduce job stress, therefore raise their job satisfaction. Thirdly, this research divided the research samples into three groups by the degree of job stress. The three groups are low satisfaction group, medium satisfaction group, and high satisfaction group. The means values of these groups were compared by t-test. Results showed that there are significant differences of the means values of interpersonal constraints between low satisfaction group and high satisfaction group. This suggests positive interpersonal relationship especially good family member relationship reduce not only job stress but also travel constraints of casino employees. Interestingly, results of t-test showed there is not a significant difference of the means values of structural constraints between low satisfaction group and high satisfaction group. This suggests structural constraints are outside variables which may be related with tourism destination marketing. Destination marketing organizations (DMO) need use all kinds of tools and techniques to promote their tourism destinations so as to reduce structural constraints of casino employees. This research is significant for both theoretical and practical fields. From the theoretical perspective, the study found the internal relationship between travel constraints, job stress, and job satisfaction and the different roles of three dimensions of travel constraints. From the practical perspective, the study provides useful methods to reduce travel constraints and job stress, therefore, raise job satisfaction of casino employees.

Keywords: hotel, job satisfaction, job stress, travel constraints

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4976 Translation Directionality: An Eye Tracking Study

Authors: Elahe Kamari

Abstract:

Research on translation process has been conducted for more than 20 years, investigating various issues and using different research methodologies. Most recently, researchers have started to use eye tracking to study translation processes. They believed that the observable, measurable data that can be gained from eye tracking are indicators of unobservable cognitive processes happening in the translators’ mind during translation tasks. The aim of this study was to investigate directionality in translation processes through using eye tracking. The following hypotheses were tested: 1) processing the target text requires more cognitive effort than processing the source text, in both directions of translation; 2) L2 translation tasks on the whole require more cognitive effort than L1 tasks; 3) cognitive resources allocated to the processing of the source text is higher in L1 translation than in L2 translation; 4) cognitive resources allocated to the processing of the target text is higher in L2 translation than in L1 translation; and 5) in both directions non-professional translators invest more cognitive effort in translation tasks than do professional translators. The performance of a group of 30 male professional translators was compared with that of a group of 30 male non-professional translators. All the participants translated two comparable texts one into their L1 (Persian) and the other into their L2 (English). The eye tracker measured gaze time, average fixation duration, total task length and pupil dilation. These variables are assumed to measure the cognitive effort allocated to the translation task. The data derived from eye tracking only confirmed the first hypothesis. This hypothesis was confirmed by all the relevant indicators: gaze time, average fixation duration and pupil dilation. The second hypothesis that L2 translation tasks requires allocation of more cognitive resources than L1 translation tasks has not been confirmed by all four indicators. The third hypothesis that source text processing requires more cognitive resources in L1 translation than in L2 translation and the fourth hypothesis that target text processing requires more cognitive effort in L2 translation than L1 translation were not confirmed. It seems that source text processing in L2 translation can be just as demanding as in L1 translation. The final hypothesis that non-professional translators allocate more cognitive resources for the same translation tasks than do the professionals was partially confirmed. One of the indicators, average fixation duration, indicated higher cognitive effort-related values for professionals.

Keywords: translation processes, eye tracking, cognitive resources, directionality

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4975 Affectness of Emotional Intelligence on Employee Profesionalism

Authors: Vanisa Damayanti Yuningsih

Abstract:

Employee professionalism is certainly the hope for every company to create a good working environment. Emotional intelligence is one of the factors that determine the success of professionalism, for, in emotional intelligence, an employee can control his ego and can understand and understand his coworkers and thus create a dynamic environment in which to work. Each employee is encouraged to have professionalism in order to optimize his resources. This professionalism is shown by employees being able to do their work and taking responsibility in their profession by involving controlled feelings and emotions. The problem which is drawn from this research is how emotional intelligence can affect the professional attitudes of employees. The purpose of this research is to find out how far emotional intelligence goes in the professional manner of employees.

Keywords: professionalism, emotional intelligence, work environment, company

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4974 Foliar Feeding of Methyl Jasmonate Induces Resistance in Normal and Salinity Stressed Tomato Plants, at Different Stages

Authors: Abdul Manan, Choudhary Muhammad Ayyub, Rashid Ahmad, Muhammad Adnan Bukhari

Abstract:

A project was designed to investigate the effect of foliar application of methyl jasmonate (MeJA) on physiological, biochemical and ionic attributes of salinity stressed and normal tomato plants at different stages. Salinity stress at every stage markedly reduced the net photosynthetic rate, stomatal conductance, transpiration rate, water relations parameters, protein contents, total free aminoacids and potassium (K+) contents. While, antioxidant enzymes (peroxidase (POX) and catalase (CAT)), sodium (Na+) contents and proline contents were increased substantially. Foliar application of MeJA ameliorated the drastic effects of salinity regime by recovery of physiological and biochemical attributes by enhanced production of antioxidant enzymes and osmoprotectants. The efficacy of MeJA at very initial stage (15 days after sowing (15 DAS)).proved effective for attenuating the deleterious effects of salinity stress than other stages (15 days after transplanting (15 DAT) and 30 days after transplanting (30 DAT)). To the best of our knowledge, different times of foliar feeding of MeJA was observed first time for amelioration of salinity stress in tomato plants that would be of pivotal significance for scientist to better understand the dynamics of physiological and biochemical processes in tomato.

Keywords: methyl jasmonate, osmoregulation, salinity stress, stress tolerance, tomato

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4973 Effects of a School-based Mindfulness Intervention on Stress Levels and Emotion Regulation of Adolescent Students Enrolled in an Independent School

Authors: Tracie Catlett

Abstract:

Students enrolled in high-achieving schools are under tremendous pressure to perform at high levels inside and outside the classroom. Achievement pressure is a prevalent source of stress for students enrolled in high-achieving schools, and female students, in particular, experience a higher frequency and higher levels of stress compared to their male peers. The practice of mindfulness in a school setting is one tool that has been linked to improved self-regulation of emotions, increased positive emotions, and stress reduction. A mixed methods randomized pretest-posttest no-treatment control trial evaluated the effects of a six-session mindfulness intervention taught during a regularly scheduled life skills period in an independent day school, one type of high-achieving school. Twenty-nine students in Grades 10 and 11 were randomized by class, where Grade 11 students were in the intervention group (n = 14) and Grade 10 students were in the control group (n = 15). Findings from the study produced mixed results. There was no evidence that the mindfulness program reduced participants’ stress levels and negative emotions. In fact, contrary to what was expected, students enrolled in the intervention group experienced higher levels of stress and increased negative emotions at posttreatment when compared to pretreatment. Neither the within-group nor the between-groups changes in stress level were statistically significant, p > .05, and the between-groups effect size was small, d = .2. The study found evidence that the mindfulness program may have had a positive impact on students’ ability to regulate their emotions. The within-group comparison and the between-groups comparison at posttreatment found that students in the mindfulness course experienced statistically significant improvement in the in their ability to regulate their emotions at posttreatment, p = .009 < .05 and p =. 034 < .05, respectively. The between-groups effect size was medium, d =.7, suggesting that the positive differences in emotion regulation difficulties were substantial and have practical implications. The analysis of gender differences, as they relate to stress and emotions, revealed that female students perceive higher levels of stress and report experiencing stress more often than males. There were no gender differences when analyzing sources of stress experienced by the student participants. Both females and males experience regular achievement pressures related to their school performance and worry about their future, college acceptance, grades, and parental expectations. Females reported an increased awareness of their stress and actively engaged in practicing mindfulness to manage their stress. Students in the treatment group expressed that the practice of mindfulness resulted in feelings of relaxation and calmness.

Keywords: achievement pressure, adolescents, emotion regulation, emotions, high-achieving schools, independent schools, mindfulness, negative affect, positive affect, stress

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4972 Prevalence of Common Mental Disorders and Its Correlation with Mental Toughness among Professional South African Rugby Players

Authors: H. B. Grobler, K. Du Plooy, P. Kruger, S. Ellis

Abstract:

Objectives: The primary objective of the study was to determine the common mental disorders (CMD) identified by professional South African rugby players and its correlation with their mental toughness, as a first step towards developing such a programme within a larger research project. Design: Survey research, within the theoretical perspective of field theory, was conducted, utilising an adaptation of an already existing mental health questionnaire. The aim was to obtain feedback from as many possible professional South African rugby players in order to make certain generalizations and come to conclusions with regard to the current mental health experiences of these rugby players. Methods: Non-randomized sampling was done, linking it with internet research in the form of the online completion of a questionnaire. A sample of 215 rugby players participated and completed the online questionnaire. Permission was obtained to make use of an existing questionnaire, previously used by the specific authors with retired professional rugby players. A section on mental toughness was added. Data were descriptively analysed by means of the SPSS software platform. Results: Results indicated that the most significant problem that the players are experiencing, is a problem with alcohol (47.9%). Other problems that featured are distress (16.3%), sleep disturbances (7%), as well as anxiety and depression (4.2%). 4.7% of the players indicated that they smoke. 3.3% of the players experience themselves as not being mentally tough. A positive correlation between mental toughness and sound sleep (0.262) was found while a negative correlation was found between mental toughness and the following: anxiety/depression (-0.401), anxiety/depression positive (-0.423), distress (-0.259) and common mental disorder problems in general (-0.220). Conclusions: Although the presence of CMD at first glance do not seem significantly high amongst all the players, it must be considered that if one player in a team experiences the presence of CMD, it will have an impact on his mental toughness and most likely on his performance, as well as on the performance of the whole team. It is therefore important to ensure mental health in the whole team, by addressing individual CMD problems. A mental health support programme is therefore needed to be implemented to the benefit of these players within the South African context.

Keywords: common mental disorders, mental toughness, professional athletes, rugby players

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4971 Thermal Elastic Stress Analysis of Steel Fiber Reinforced Aluminum Composites

Authors: Mustafa Reşit Haboğlu, Ali Kurşun , Şafak Aksoy, Halil Aykul, Numan Behlül Bektaş

Abstract:

A thermal elastic stress analysis of steel fiber reinforced aluminum laminated composite plate is investigated. Four sides of the composite plate are clamped and subjected to a uniform temperature load. The analysis is performed both analytically and numerically. Laminated composite is manufactured via hot pressing method. The investigation of the effects of the orientation angle is provided. Different orientation angles are used such as [0°/90°]s, [30°/-30°]s, [45°/-45°]s and [60/-60]s. The analytical solution is obtained via classical laminated composite theory and the numerical solution is obtained by applying finite element method via ANSYS.

Keywords: laminated composites, thermo elastic stress, finite element method.

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4970 Thermal Fracture Analysis of Fibrous Composites with Variable Fiber Spacing Using Jk-Integral

Authors: Farid Saeidi, Serkan Dag

Abstract:

In this study, fracture analysis of a fibrous composite laminate with variable fiber spacing is carried out using Jk-integral method. The laminate is assumed to be under thermal loading. Jk-integral is formulated by using the constitutive relations of plane orthotropic thermoelasticity. Developed domain independent form of the Jk-integral is then integrated into the general purpose finite element analysis software ANSYS. Numerical results are generated so as to assess the influence of variable fiber spacing on mode I and II stress intensity factors, energy release rate, and T-stress. For verification, some of the results are compared to those obtained using displacement correlation technique (DCT).

Keywords: Jk-integral, Variable Fiber Spacing, Thermoelasticity, T-stress, Finite Element Method, Fibrous Composite.

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4969 A Novel Gene Encoding Ankyrin-Repeat Protein, SHG1, Is Indispensable for Seed Germination under Moderate Salt Stress

Authors: H. Sakamoto, J. Tochimoto, S. Kurosawa, M. Suzuki, S. Oguri

Abstract:

Salt stress adversely affects plant growth at various stages of development including seed germination, seedling establishment, vegetative growth and finally reproduction. Because of their immobile nature, plants have evolved mechanisms to sense and respond to salt stress. Seed dormancy is an adaptive trait that enables seed germination to coincide with favorable environmental conditions. We identified a novel locus of Arabidopsis, designated SHG1 (salt hypersensitive germination 1), whose disruption leads to reduced germination rate under moderate salt stress conditions. SHG1 encodes a transmembrane protein with an ankyrin repeat motif that has been implicated in diverse cellular processes such as signal transduction. The SGH1-disrupted Arabidopsis mutant died at the cotyledon stage when sown on salt-containing medium, although wild type plants could form true leaves under the same conditions. On the other hand, this mutant showed similar phenotypes to wild type plants when sown on medium without salt and transferred to salt-containing medium at the vegetative stage. These results suggested that SHG1 played indispensable role in the seed germination and seedling establishment under moderate salt stress conditions. SHG1 may be involved in the release of seed dormancy.

Keywords: germination, ankyrin repeat, arabidopsis, salt tolerance

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4968 A Qualitative Study of Experienced Early Childhood Teachers Resolving Workplace Challenges with Character Strengths

Authors: Michael J. Haslip

Abstract:

Character strength application improves performance and well-being in adults across industries, but the potential impact of character strength training among early childhood educators is mostly unknown. To explore how character strengths are applied by early childhood educators at work, a qualitative study was completed alongside professional development provided to a group of in-service teachers of children ages 0-5 in Philadelphia, Pennsylvania, United States. Study participants (n=17) were all female. The majority of participants were non-white, in full-time lead or assistant teacher roles, had at least ten years of experience and a bachelor’s degree. Teachers were attending professional development weekly for 2 hours over a 10-week period on the topic of social and emotional learning and child guidance. Related to this training were modules and sessions on identifying a teacher’s character strength profile using the Values in Action classification of 24 strengths (e.g., humility, perseverance) that have a scientific basis. Teachers were then asked to apply their character strengths to help resolve current workplace challenges. This study identifies which character strengths the teachers reported using most frequently and the nature of the workplace challenges being resolved in this context. The study also reports how difficult these challenges were to the teachers and their success rate at resolving workplace challenges using a character strength application plan. The study also documents how teachers’ own use of character strengths relates to their modeling of these same traits (e.g., kindness, teamwork) for children, especially when the nature of the workplace challenge directly involves the children, such as when addressing issues of classroom management and behavior. Data were collected on action plans (reflective templates) which teachers wrote to explain the work challenge they were facing, the character strengths they used to address the challenge, their plan for applying strengths to the challenge, and subsequent results. Content analysis and thematic analysis were used to investigate the research questions using approaches that included classifying, connecting, describing, and interpreting data reported by educators. Findings reveal that teachers most frequently use kindness, leadership, fairness, hope, and love to address a range of workplace challenges, ranging from low to high difficulty, involving children, coworkers, parents, and for self-management. Teachers reported a 71% success rate at fully or mostly resolving workplace challenges using the action plan method introduced during professional development. Teachers matched character strengths to challenges in different ways, with certain strengths being used mostly when the challenge involved children (love, forgiveness), others mostly with adults (bravery, teamwork), and others universally (leadership, kindness). Furthermore, teacher’s application of character strengths at work involved directly modeling character for children in 31% of reported cases. The application of character strengths among early childhood educators may play a significant role in improving teacher well-being, reducing job stress, and improving efforts to model character for young children.

Keywords: character strengths, positive psychology, professional development, social-emotional learning

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4967 Investigation of the Relationship between Digital Game Playing, Internet Addiction and Perceived Stress Levels in University Students

Authors: Sevim Ugur, Cemile Kutmec Yilmaz, Omer Us, Sevdenur Koksaldi

Abstract:

Aim: This study aims to investigate the effect of digital game playing and Internet addiction on perceived stress levels in university students. Method: The descriptive study was conducted through face-to-face interview method with a total of 364 university students studying at Aksaray University between November 15 and December 30, 2017. The research data were collected using personal information form, a questionnaire to determine the characteristics of playing digital game, the Internet addiction scale and the perceived stress scale. In the evaluation of the data, Mann-Whitney U test was used for two-group comparison of the sample with non-normal distribution, Kruskal-Wallis H-test was used in the comparison of more than two groups, and the Spearman correlation test was used to determine the relationship between Internet addiction and the perceived stress level. Results: It was determined that the mean age of the students participated in the study was 20.13 ± 1.7 years, 67.6% was female, 35.7% was sophomore, and 62.1% had an income 500 TL or less. It was found that 83.5% of the students use the Internet every day and 70.6% uses the Internet for 5 hours or less per day. Of the students, 12.4% prefers digital games instead of spending time outdoors, 8% plays a game as the first activity in leisure time, 12.4% plays all day, 15.7% feels anger when he/she is prevented from playing, 14.8% prefers playing games to get away from his/her problems, 23.4% had his/her school achievement affected negatively because of game playing, and 8% argues with family members due to the time spent for gaming. Students who play games on the computer for a long time were found to feel back pain (30.8%), headache (28.6%), insomnia (26.9%), dryness and pain in the eyes (26.6%), pain in the wrist (21.2%), feeling excessive tension and anger (16.2%), humpback (12.9), vision loss (9.6%) and pain in the wrist and fingers (7.4%). In our study, students' Internet addiction scale mean score was found to be 45.47 ± 16.1 and mean perceived stress scale score was 28.56 ± 2.7. A significant and negative correlation (p=0.037) was found between the total score of the Internet addiction scale and the total score of the perceived stress scale (r=-0.110). Conclusion: It was found in the study that Internet addiction and perceived stress of the students were at a moderate level and that there was a negative correlation between Internet addiction and perceived stress levels. Internet addiction was found to increase with the increasing perceived stress levels of students, and students were found to have health problems such as back pain, dryness in the eyes, pain, insomnia, headache, and humpback. Therefore, it is recommended to inform students about different coping methods other than spending time on the Internet to cope with the stress they perceive.

Keywords: digital game, internet addiction, student, stress level

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4966 Effect of Citrulline on the Physical Performance of a Soccer-Specific Exercises in Adult Professional Soccer Players

Authors: Bezuglov Eduard, Ryland Morgans, Talibov Oleg, Kalinin Evgeny, Butovsky Mikhail, Savin Evgeny, Tzgoev Eduard, Artemii Lazarev, Bekzhan Pirmakhanov, Anthony C. Hackney

Abstract:

Currently, there is conflicting evidence regarding the efficacy of citrulline for physical performance and post-exercise recovery. Moreover, the vast majority of studies conducted used physically active volunteers from the general population and heterogeneous exercise protocols that are not specific to most sports. A single use of citrulline, regardless of the dose, will not have a significant effect on physical performance and post-exercise recovery in highly trained soccer players performing sport-specific exercises at maximum intensity. To evaluate the effectiveness of a single administration of citrulline at various doses in adult male professional soccer players performing sport-specific exercise at maximum intensity. A randomized, double-blind, placebo-controlled study analyzing eighteen soccer players from the top divisions of several European countries. The participants were randomized into three groups of six and performed a field-based soccer-specific test at 115% VO2max for 18-minutes. Comparative analysis of the cardiovascular system, physical activity, subjective perceived fatigue and post-exercise recovery was conducted. There were no statistically significant differences in more than one analyzed parameter. A single application of 3 to 6 grams of citrulline does not affect physical performance, subjective feeling of fatigue and post-exercise recovery in adult professional soccer players who have performed a sport-specific test. Currently, citrulline cannot be recommended for use as a supplement in adult professional soccer players

Keywords: citrulline, performance, recovery, soccer players

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