Search results for: workplace stress

Authors: S. Ghanaraja, Subrata Ray, S. K. Nath

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Particle reinforced Metal Matrix Composite (MMC) succeeds in synergizing the metallic matrix with ceramic particle reinforcements to result in improved strength, particularly at elevated temperatures, but adversely it affects the ductility of the matrix because of agglomeration and porosity. The present study investigates the outcome of tensile properties in a cast and hot forged composite reinforced simultaneously with coarse and fine particles. Nano-sized alumina particles have been generated by milling mixture of aluminum and manganese dioxide powders. Milled particles after drying are added to molten metal and the resulting slurry is cast. The microstructure of the composites shows good distribution of both the size categories of particles without significant clustering. The presence of nanoparticles along with coarser particles in a composite improves both strength and ductility considerably. Delay in debonding of coarser particles to higher stress is due to reduced mismatch in extension caused by increased strain hardening in presence of the nanoparticles. However, higher addition of powder mix beyond a limit results in deterioration of mechanical properties, possibly due to clustering of nanoparticles. The porosity in cast composite generally increases with the increasing addition of powder mix as observed during process and on forging it has got reduced. The base alloy and nanocomposites show improvement in flow stress which could be attributed to lowering of porosity and grain refinement as a consequence of forging.

Keywords: aluminium, alumina, nano-particle reinforced composites, porosity

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Authors: M. Cabuk, M. Yavuz, T. A. Yesil, H. I. Unal

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Electrorheological (ER) fluids are a class of smart materials exhibiting reversible changes in their rheological and mechanical properties under an applied electric field (E). ER fluids generally are composed of polarisable solid particles dispersed in non-conducting oil. ER fluids are fluids which exhibit. The resistance to motion of the ER fluid can be controlled by adjusting the applied E, due to their fast and reversible changes in their rheological properties presence of E. In this study, a series of chitosan/expanded perlite (CS/EP) composites with different chitosan mass fractions (10%, 20%, and 50%) was used. Characterizations of the composites were carried out by Fourier Transform Infrared (FTIR), X-ray diffraction (XRD) and Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) techniques. Antisedimentation stability and dielectric properties of the composites were also determined. The effects of volume fraction, electric field strength, shear rate, shear stress, and temperature onto ER properties of the CS/EP composite particles dispersed in silicone oil (SO) were investigated in detail. Vibration damping behavior of the CS/EP composites were determined as a function of frequence, storage (Gʹ) and loss (Gʹ ʹ) moduli. It was observed that ER response of the CS/EP/SO ER fluids increased with increasing electric field strength and exhibited the typical shear thinning non-Newtonian viscoelastic behaviors with increasing shear rate. The maximum yield stress was obtained with 1250 Pa under E = 3 kV/mm. Further, the CS/EP/SO ER fluids were observed to sensitive to vibration control by showing reversible viscosity enhancements (Gʹ > Gʹ ʹ). Acknowledgements: The authors thank the TÜBİTAK (214Z199) for the financial support of this work.

Keywords: chitosan, electrorheology, perlite, vibration control

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Authors: Hanjong Kim, Changwan Han, Seonghun Park

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Heat exchanger manifolds in aircraft play an important role in evenly distributing the fluid entering through the inlet to the heat transfer unit. In order to achieve this requirement, the manifold should be designed to have a light weight by withstanding high internal pressure. Therefore, this study aims at minimizing the weight of the heat exchanger manifold through topology optimization. For topology optimization, the initial design space was created with the inner surface extracted from the currently used manifold model and with the outer surface having a dimension of 243.42 mm of X 74.09 mm X 65 mm. This design space solid model was transformed into a finite element model with a maximum tetrahedron mesh size of 2 mm using ANSYS Workbench. Then, topology optimization was performed under the boundary conditions of an internal pressure of 5.5 MPa and the fixed support for rectangular inlet boundaries by SIMULIA TOSCA. This topology optimization produced the minimized finial volume of the manifold (i.e., 7.3% of the initial volume) based on the given constraints (i.e., 6% of the initial volume) and the objective function (i.e., maximizing manifold stiffness). Weight of the optimized model was 6.7% lighter than the currently used manifold, but after smoothing the topology optimized model, this difference would be bigger. The current optimized model has uneven thickness and skeleton-shaped outer surface to reduce stress concentration. We are currently simplifying the optimized model shape with spline interpolations by reflecting the design characteristics in thickness and skeletal structures from the optimized model. This simplified model will be validated again by calculating both stress distributions and weight reduction and then the validated model will be manufactured using 3D printing processes.

Keywords: topology optimization, manifold, heat exchanger, 3D printing

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Authors: Vitheejongjaroen P., Jaisin Y., Pachekrepapol U., Taweechotipatr M.

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Lactic acid bacteria (LAB) are the most common type of microorganisms that had been used as probiotics also known for many beneficial health effects. The antioxidant activity of LAB is associated with numerous health-protective effects. This research aimed to investigate the antioxidant activity of lactic acid bacteria isolated from Thai sour pork sausage for their application in fermented milk products. Antioxidant activity determined by DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assay showed that the isolate FN33-7, as 1 of 8 isolated exhibited scavenging activity in intact cell 5-7%, and supernatant 13-16%, intracellular cell free extract 42-48% respectively. This isolate was identified using 16S ribosomal DNA sequence analysis as Lactobacillus plantarum. The effect of milk fermented with L. plantarum FN33-7 on microbial count, pH and syneresis was assessed during refrigerated storage period of 28 days. The strain showed increased viability, pH level decreased, while syneresis increased. These results are similar to dairy products fermented with commercial starter cultures. Additionally, microstructure analysis of fermented milk by fluorescent microscopy showed that curd structure appeared to be dense and less porous in this fermented milk than commercial yogurt. The results of this study indicated that L. plantarum FN33-7 was a good probiotic candidate to be used in cultured milk products to reduce the risk of diseases caused by oxidative stress.

Keywords: Lactobacillus plantarum, probiotics, free radical, antioxidant, oxidative stress, fermented milk products

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Authors: Chi-Yuan Huang, Mei-Chuan Kuo, Ching-Yi Hsiao

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In this study, acids with various chain lengths (C₆, C₈, C₁₀ and C₁₂) modified by methane sulfonic acid (MSA) and temperature were used to modify tapioca starch (TPS), then the glycerol (GA) were added into modified starch, to prepare new blends. The mechanical properties, thermal properties and physical properties of blends were studied. This investigation was divided into two parts.  First, the biodegradable materials were used such as starch and glycerol with hexanedioic acid (HA), suberic acid (SBA), sebacic acid (SA), decanedicarboxylic acid (DA) manufacturing with different temperatures (90, 110 and 130 °C). And then, the solution was added into modified starch to prepare the blends by using single-screw extruder. The FT-IR patterns indicated that the characteristic peak of C=O in ester was observed at 1730 cm^-1. It is proved that different chain length acids (C₆, C₈, C₁₀ and C₁₂) reacted with glycerol by esterification and these are used to plasticize blends during extrusion. In addition, the blends would improve the hydrolysis and thermal stability. The water contact angle increased from 43.0° to 64.0°.  Second, the HA (110 °C), SBA (110 °C), SA (110 °C), and DA blends (130 °C) were used in study, because they possessed good mechanical properties, water resistances and thermal stability. On the other hand, the various contents (0, 0.005, 0.010, 0.020 g) of MSA were also used to modify the mechanical properties of blends. We observed that the blends were added to MSA, and then the FT-IR patterns indicated that the C=O ester appeared at 1730 cm^-1. For this reason, the hydrophobic blends were produced. The water contact angle of the MSA blends increased from 55.0° to 71.0°. Although break elongation of the MSA blends reduced from the original 220% to 128%, the stress increased from 2.5 MPa to 5.1 MPa. Therefore, the optimal composition of blends was the DA blend (130 °C) with adding of MSA (0.005 g).

Keywords: chain length acids, methane sulfonic acid, Tapioca starch (TPS), tensile stress

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Authors: Micheale Yifter Weldemichael

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Sesame (Sesamum indicum L.) is among the most important oilseed crops for its high edible oil quality and quantity. Sesame is grown for food, medicinal, pharmaceutical, and industrial uses. Sesame is also cultivated as a main cash crop in Asia and Africa by smallholder farmers. Despite the global exponential increase in sesame cultivation area, its production and productivity remain low, mainly due to biotic and abiotic constraints. Notwithstanding the efforts to solve these problems, a low level of genetic variation and inadequate genomic resources hinder the progress of sesame improvement. The objective of this paper is, therefore, to review recent advances in the area of molecular breeding and transformation to overcome major production constraints and could result in enhanced and sustained sesame production. This paper reviews various researches conducted to date on molecular breeding and genetic transformation in sesame focusing on molecular markers used in assessing the available online database resources, genes responsible for key agronomic traits as well as transgenic technology and genome editing. The review concentrates on quantitative and semi-quantitative studies on molecular breeding for key agronomic traits such as improvement of yield components, oil and oil-related traits, disease and insect/pest resistance, and drought, waterlogging and salt tolerance, as well as sesame genetic transformation and genome editing techniques. Pitfalls and limitations of existing studies and methodologies used so far are identified and some priorities for future research directions in sesame genetic improvement are identified in this review.

Keywords: abiotic stress, biotic stress, improvement, molecular breeding, oil, sesame, shattering

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Authors: Calassandra Nwokoro

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Introduction: The nursing profession requires a lot of commitment, effort, and time to efficiently manage patients and provide them quality healthcare services, this work load may eventually cause the nurses to become burned out and experience psychological distress. This study assessed the prevalence of burnout, risk factors, and the coping strategies among nurses working in Lagos University Teaching Hospital (LUTH), Lagos state, Nigeria. Methodology: A descriptive cross-sectional study design was conducted among 308 nurses working in LUTH. Simple random sampling was used in selection of study respondents. The questionnaire comprised three parts; the sociodemographic characteristics of the respondents, the extent of burnout syndrome using the Maslach Burnout Inventory, and the coping strategies used among the respondents using the BRIEF-COPE Inventory. Results: This study revealed relatively high levels of burnout among the nurses in LUTH with a prevalence of 16.9%, 31.2% and 20.1% for high emotional exhaustion, high depersonalization and reduced professional accomplishment respectively. It also showed that burnout was significantly associated with long working hours. Religion was found to be the most commonly used coping strategy overall, while emotional support was the most frequently used coping strategy among nurses who had burnout. Conclusion: This study has revealed a relatively high prevalence of burnout among the nurses in Lagos University Teaching Hospital. In order to minimize the negative health impacts of burnout, the government should collaborate with psychologists and psychiatrists to implement regular stress management and stress inoculation programs for nurses and other health professionals in the country.

Keywords: burnout, nurses, coping strategies, healthcare

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Authors: Wassim Guermazi, Saoussan Boukhris, Neila Annabi Trabelsi, Tarek Rebai, Alya Sellami-Kamoun, Habib Ayadi

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This work investigates the protective effects of the microalga Halamphora sp. extract (H. Ext) as a natural product on lead-intoxicated liver and kidney human cells in vitro and in vivo on rats wistar. HepG2 cells line derived from human hepatocellular carcinoma and HEK293 cells line derived from human embryonic kidney were used for the in vitro study. The analysis of the fatty acids methyl esters of the extract was performed by a GC/MS. Four groups of rats, each of which was composed of six animals, were used for the in vivo experiment. The pretreatment of HepG2 and HEK293 cells line with the extract (100 µg mL-1) significantly (p < 0.05) protected against cytotoxicity induced by lead exposure. In vivo, the biochemical parameters in serum, namely malondialdehyde level (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities, were measured in supernatants of organ homogenates. H. Ext was found to be rich in fatty acids, essentially palmitic and palmitoleic accounting respectively 29.46% and 42.07% of total fatty acids. Both in vitro and in vivo, the co-treatment with H. Ext allowed the protection of the liver and kidney cells structure, as well as the significant preservation of normal antioxidant and biochemical parameters in rats. Halamphora extract rich in fatty acids has been proven to be effective in protection against Pb-induced toxicity.

Keywords: microalga extract, human cells line, fatty acid, lead exposure, oxidative stress, rats

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Authors: Radek Novotny, Michal Novak, Daniela Marusakova, Monika Sipova, Hugo Fuentes, Peter Borst

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This research has been conducted within the European HORIZON 2020 project ECC-SMART. The main objective is to assess whether it is feasible to design and develop a small modular reactor (SMR) that would be cooled by supercritical water (SCW). One of the main objectives for material research concerns the corrosion of the candidate cladding materials. The experimental part has been conducted in support of the qualification procedure of the future SCW-SMR constructional materials. The last objective was to identify the gaps in current norms and guidelines. Apart from corrosion, resistance testing of candidate materials stresses corrosion cracking susceptibility tests have been performed in supercritical water. This paper describes part of these tests, in particular, those slow strain rate tensile loading applied for tangential ring shape specimens of two candidate materials, Alloy 800H and 310S stainless steel. These ring tensile tests are one the methods used for tensile testing of nuclear cladding. Here full circular heads with dimensions roughly equal to the inner diameter of the sample and the gage sections are placed in the parallel direction to the applied load. Slow strain rate tensile tests have been conducted in 380 or 500oC supercritical water applying two different elongation rates, 1x10-6 and 1x10-7 s-1. The effect of temperature and dissolved oxygen content on the SCC susceptibility of Alloy 800H and 310S stainless steel was investigated when two different temperatures and concentrations of dissolved oxygen were applied in supercritical water. The post-fracture analysis includes fractographic analysis of the fracture surfaces using SEM as well as cross-sectional analysis on the occurrence of secondary cracks. Assessment of the effect of environment and dissolved oxygen content was by comparing to the results of the reference tests performed in air and N2 gas overpressure. The effect of high temperature on creep and its role in the initiation of SCC was assessed as well. It has been concluded that the applied test method could be very useful for the investigation of stress corrosion cracking susceptibility of candidate cladding materials in supercritical water.

Keywords: stress corrosion cracking, ring tensile tests, super-critical water, alloy 800H, 310S stainless steel

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Authors: Amira Potter

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Since three years, ESPRIT has adopted project-based learning across its curricula. The philosophy behind this reform is to prepare its future engineers to become more operational once they integrate the workplace. It allows them to learn all the required skills expected from them by their future employers. This learner-centered method helps the students take responsibility for their own learning, solve real-world problems and carry out muli-faceted projects. Therefore, the teacher who used to be considered as the detainer of the knowledge has become more of a facilitator and a coach, encouraging their students’ learning process. This innovative way to English teaching has enabled the students to learn the English language differently. The target language is learnt cooperatively through group work, presentations, debating and many other communicative activities. The speaking skill in English language remains by far the most challenging skill for Tunisian students with an educational background based on Arabic as a first language and French as a second language. The student’s initial resistance to speak English in front of their classmates and the way they end up performing their work, shows the real progress they managed to achieve through PBL approach. The article will focus on the positive impact PBL has had on oral fluency among Esprit engineering students and how it has been achieved. It will also describe how speaking skill is taught and assessed at ESPRIT.

Keywords: cooperative, engineer, innovative, project-based learning

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Authors: Nina Kaufmans

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Traditional therapies, utilizing spoken narratives as a primary source of intervention, are proven to be limited in effectively treating post traumatic stress disorder. Following the effects of the global pandemic of COVID-19, an increasing number of mental health consumers are beginning to experience somatically-based distress in addition to existing mental health symptoms. Moreover, the aftermath of the rapid increase in demand for mental health services has caused significant burnout in mental health professionals. This paper explores the ramifications of recent changes and challenges in the mental health demands and subsequent response and its consequences for mental health workers. We will begin by investigating the neurobiological mechanisms involved in traumatic experiences, then discuss the premises for "bottom-up" or somatically oriented psychotherapy approaches, and finally offer clinical skills and interventions for clients diagnosed with post traumatic stress disorder. In addition, we will discuss how somatically-based psychotherapy interventions implemented in sessions may decrease burnout and improve the well-being of clinicians. We will discuss how the integration of somatically-based interventions into counseling would increase the effectiveness of mental health recovery and sustain remission while simultaneously providing opportunities for self-care for mental health professionals.

Keywords: somatic psychotherapy interventions, trauma counseling, preventing and treating burnout, adults with PTSD, bottom-up skills, the effectiveness of trauma treatment

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Authors: Claudius Peter Van Wyk

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Given the increasingly manifest phenomena, as described in complexity theory, of volatility, uncertainty, complexity and ambiguity (VUCA), Taleb's notion of 'antifragility, has a significant contribution to make to positive psychology applied to wellbeing. Antifragility is argued to be fundamentally different from the concepts of resiliency; as the ability to recover from failure, and robustness; as the ability to resist failure. Rather it describes the capacity to reorganise in the face of stress in such a way as to cope more effectively with systemic challenges. The concept, which has been applied in disciplines ranging from physics, molecular biology, planning, engineering, and computer science, can now be considered for its application in individual human and social wellbeing. There are strong correlations to Antonovsky's model of 'salutogenesis' in which an attitude and competencies are developed of transforming burdening factors into greater resourcefulness. We demonstrate, from the perspective of neuroscience, how technology measuring nervous system coherence can be coupled to acquired psychodynamic approaches to not only identify contextual stressors, utilise biofeedback instruments for facilitating greater coherence, but apply these insights to specific life stressors that compromise well-being. Employing an on-going case study with BMW South Africa, the neurological mapping is demonstrated together with 'reframing' and emotional anchoring techniques from neurolinguistic programming. The argument is contextualised in the discipline of psychoneuroimmunology which describes the stress pathways from the CNS and endocrine systems and their impact on immune function and the capacity to restore homeostasis.

Keywords: antifragility, complexity, neuroscience, psychoneuroimmunology, salutogenesis, volatility

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Authors: Hamid Ahmadi, Amirreza Ghaffari

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Fatigue life of tubular joints in offshore structures is not only dependent on the value of hot-spot stress, but is also significantly influenced by the through-the-thickness stress distribution characterized by the degree of bending (DoB). The DoB exhibits considerable scatter calling for greater emphasis in accurate determination of its governing probability distribution which is a key input for the fatigue reliability analysis of a tubular joint. Although the tubular X-joints are commonly found in offshore jacket structures, as far as the authors are aware, no comprehensive research has been carried out on the probability distribution of the DoB in tubular X-joints. What has been used so far as the probability distribution of the DoB in reliability analyses is mainly based on assumptions and limited observations, especially in terms of distribution parameters. In the present paper, results of parametric equations available for the calculation of the DoB have been used to develop probability distribution models for the DoB in the chord member of tubular X-joints subjected to four types of bending loads. Based on a parametric study, a set of samples was prepared and density histograms were generated for these samples using Freedman-Diaconis method. Twelve different probability density functions (PDFs) were fitted to these histograms. The maximum likelihood method was utilized to determine the parameters of fitted distributions. In each case, Kolmogorov-Smirnov test was used to evaluate the goodness of fit. Finally, after substituting the values of estimated parameters for each distribution, a set of fully defined PDFs have been proposed for the DoB in tubular X-joints subjected to bending loads.

Keywords: tubular X-joint, degree of bending (DoB), probability density function (PDF), Kolmogorov-Smirnov goodness-of-fit test

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Authors: Neringa Bagdonaite

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Study Aims: The current study aimed to systematically analyse various research done in the area of female post-traumatic stress disorder (PTSD) and alcohol abuse, and to critically review these results on the basis of theoretical models as well as answer following questions: (I) What is the reciprocal relationship between PTSD and problem alcohol use among females; (II) What are the moderating/mediating factors of this relationship? Methods: The computer bibliographic databases Ebsco, Scopus, Springer, Web of Science, Medline, Science Direct were used to search for scientific articles. Systematic analyses sample consisted of peer-reviewed, English written articles addressing mixed gender and female PTSD and alcohol abuse issues from Jan 2012 to May 2017. Results: Total of 1011 articles were found in scientific databases related to searched keywords of which 29 met the selection criteria and were analysed. The results of longitudinal studies indicate that (I) various trauma, especially interpersonal trauma exposure in childhood is linked with increased risk of revictimization in later life and problem alcohol use; (II) revictimization in adolescence or adulthood, rather than victimization in childhood has a greater impact on the onset and progression of problematic alcohol use in adulthood. Cross-sectional and epidemiological studies also support significant relationships between female PTSD and problem alcohol use. Regards to the negative impact of alcohol use on PTSD symptoms results are yet controversial; some evidence suggests that alcohol does not exacerbate symptoms of PTSD over time, while others argue that problem alcohol use worsens PTSD symptoms and is linked to chronicity of both disorders, especially among women with previous alcohol use problems. Analysis of moderating/mediating factors of PTSD and problem alcohol use revealed, that higher motives/expectancies, specifically distress coping motives for alcohol use significantly moderates the relationship between PTSD and problematic alcohol use. Whereas negative affective states mediate relationship between symptoms of PTSD and alcohol use, but only among woman with alcohol use problems already developed. Conclusions: Interpersonal trauma experience, especially in childhood and its reappearance in lifetime is linked with PTSD symptoms and problem drinking among women. Moreover, problem alcohol use can be both a cause and a consequence of trauma and PTSD, and if used for coping it, increases the likelihood of chronicity of both disorders. In order to effectively treat both disorders, it’s worthwhile taking into account this dynamic interplay of women's PTSD symptoms and problem drinking.

Keywords: female, trauma, post-traumatic stress disorder, problem alcohol use, systemic analysis

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Authors: Claudia Cedeno Nadal, Mei-Ling Villafana, Griela Rodriguez, Jessica Martin, Jennifer Martin, Megan Patel

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This study systematically examines the impact of Transcendental Mindfulness Meditation on anxiety symptoms in young females aged 18-25. Through a comprehensive literature review, we found consistent evidence supporting the positive influence of Transcendental Mindfulness Meditation on reducing anxiety, enhancing overall well-being, and decreasing perceived stress levels within this demographic. The mechanisms underlying these effects include heightened self-awareness, improved emotional regulation, and the development of effective stress-coping strategies. These findings have significant implications for mental health interventions targeting young females. However, the reviewed studies had some limitations, such as small sample sizes and reliance on self-report measures. To advance this field, future research should focus on larger sample sizes and utilize a broader range of measurement methods, including neuroscience assessments. Additionally, investigating the temporal relationships between Transcendental Mindfulness Meditation, proposed mediators, and anxiety symptoms will help establish causal specificity and a deeper understanding of the precise mechanisms of action. The development of integrative models based on these mechanisms can further enhance the effectiveness of Transcendental Mindfulness Meditation as an intervention for anxiety in this demographic. This study contributes to the current knowledge on the potential benefits of Transcendental Mindfulness Meditation for reducing anxiety in young females, paving the way for more targeted and effective mental health interventions in this population.

Keywords: mindfulness, meditation, anxiety, transcendental mindfulness

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Authors: Muhammad Akram, Abdurrahman Ilgan, Oyku Ozu-Cengiz

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The quality of Work life is the general state of wellbeing of employees in the workplace. The quality of work life focuses on changing climate at work so that employees can lead improved work life. This study was designed to compare the quality of work life between Turkish and Pakistani public school teachers based on their location, gender, and marital status. A 30 items scale named The Quality of School Work Life (QSWL) was used for this study. 995 teachers from 8 Turkish provinces and 716 from four Pakistani districts were conveniently selected. The overall reliability coefficient of the scale was measured as .81. Exploratory and confirmatory factor analysis yielded five subscales of the construct. The Study revealed that Turkish and Pakistani teachers significantly differed, separately, on all the five subscales of Quality of School Work Life. However, no significant differences were found between Turkish and Pakistani teachers perspectives on the composite score of the QSWL. Further, Male, married, and Single teachers did not significantly differ on their perceptions of QSWL in both countries. However, Pakistani female teachers significantly perceived better QSWL than female teachers in Turkey. The study provided initial validity and reliability evidence of the QSWL.

Keywords: developmental opportunities, fair wages, quality of work life, Pakistan

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Authors: Ageliki I. Katsarou, Andriana C. Kaliora, Antonia Chiou, Apostolos Papalois, Nick Kalogeropoulos, Nikolaos K. Andrikopoulos

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Oxidative stress is a major mechanism underlying CVDs while inflammation, an intertwined process with oxidative stress, is also linked to CVDs. Extra virgin olive oil (EVOO) is widely known to play a pivotal role in CVD prevention and CVD reduction. However, in most studies, olive oil constituents are evaluated individually and not as part of the native food, hence potential synergistic effects as drivers of EVOO beneficial properties may be underestimated. In this study, EVOO lipidic and polar phenolics fractions were evaluated for their effect on inflammatory (TNF-alpha) and oxidation (malondialdehyde/MDA) markers, in cholesterol-fed rats. Thereat, oils with discernible lipidic profile and polar phenolic content were used. Wistar rats were fed on either a high-cholesterol diet (HCD) or a HCD supplemented with oils, either commercially available, i.e. EVOO, sunflower oil (SO), or modified as to their polar phenol content, i.e. phenolics deprived-EVOO (EVOOd), SO enriched with the EVOO phenolics (SOe). After 9 weeks of dietary intervention, heart and blood samples were collected. HCD induced dylipidemia shown by increase in serum total cholesterol, low-density lipoprotein cholesterol (LDL-c) and triacylglycerols. Heart tissue has been affected by dyslipidemia; oxidation was indicated by increase in MDA in cholesterol-fed rats and inflammation by increase in TNF-alpha. In both cases, this augmentation was attenuated in EVOO and SOe diets. With respect to oxidation, SO enrichment with the EVOO phenolics brought its lipid peroxidation levels as low as in EVOO-fed rats. This suggests that phenolic compounds may act as antioxidant agents in rat heart. A possible mechanism underlying this activity may be the protective effect of phenolics in mitochondrial membrane against oxidative damage. This was further supported by EVOO/EVOOd comparison with the former presenting lower heart MDA content. As for heart inflammation, phenolics naturally present in EVOO as well as phenolics chemically added in SO, exhibited quenching abilities in heart TNF-alpha levels of cholesterol-fed rats. TNF-alpha may have played a causative role in oxidative stress induction while the opposite may have also happened, hence setting up a vicious cycle. Overall, diet supplementation with EVOO or SOe attenuated hypercholesterolemia-induced increase in MDA and TNF-alpha in Wistar rat hearts. This is attributed to phenolic compounds either naturally existing in olive oil or as fortificants in seed oil.

Keywords: extra virgin olive oil, hypercholesterolemic rats, MDA, polar phenolics, TNF-alpha

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Authors: Josephine Muchiri, Makena Muriithi

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Adverse mental health consequences are experienced by those that have been touched by Intimate Partner Violence (IPV), whether directly or indirectly. These negative effects are felt not only in the short term but in years to come. It is important to examine the prevalence and co-occurrence of mental disorders in order to provide strategic interventions for women who have experienced IPV. The aim of this study was to examine the prevalence and comorbidity of post-traumatic stress disorder (PTSD), Depression, and Anxiety among women who had experienced intimate Partner violence in two selected informal settlements in Nairobi County, Kenya. Participants were 116 women (15-60 years) selected through purposive and snowball sampling from the low social, economic settlements (Kawangware and Kibera) in Nairobi, Kenya. A social demographic questionnaire and the Woman Abuse Screening Tool (WAST) were used to collect data on intimate partner violence experiences. The PTSD Checklist for DSM-5 (PCL-5), Beck’s Depression Inventory, and the Beck’s Anxiety Inventory assessed for post-traumatic stress disorder, depression, and anxiety, respectively. Data analysis was conducted using the Statistical Package for Social Sciences (SPSS) version 29, utilizing descriptive and correlation analyses. Findings indicated that the women had undergone various forms of abuse from their intimate partners, which were physical abuse 111(92.5%), sexual abuse 70(88.6%), and verbal abuse 92(93.9%). The prevalence of the mental disorders was PTSD 47(32.4%); M= 44.11, S.D =14.67, depression was the highest at n=131(90.3%; M=33.37±9.98) with the levels of depression having varying prevalence rates where severe depression had the highest representation [moderate: n= 35; 24.1%, severe: n=69 (47.6%) and extremely severe: n=27(18.6%)]. Anxiety had the second highest prevalence of n=99 (68.8%; M= 28.55±13.63) with differing prevalence rates in the levels of anxiety which were normal anxiety: 45(31.3%), moderate anxiety n=62(43.1%) and severe anxiety: n=37(25.7%). Regarding comorbidities, the Pearson correlation test showed that there was a significant (p=0.000) positive relationship between PTSD and depression (r=0.379; p=.000), PTSD and anxiety (r=0.624; p=.000), and depression and anxiety (r=0.386; p=.000) such that increase in one disorder concomitantly led to increase of the other two disorders; hence comorbidity of the three disorders was ascertained. Conclusion: The study asserted the adverse impacts of IPV on women’s mental well-being, where the prevalence of PTSD, depression, and anxiety was established. Almost all the women had depressive symptoms; whereas more than half had anxiety and slightly more than a third had PTSD. Regarding the severity levels of anxiety and depression, almost half of the women with depression had severe depression whereas moderate anxiety was more prevalent for those with anxiety. The three disorders were found to co-occur where comorbidities of PTSD and anxiety had the highest probability of co-occurrence. It is thus recommended that mental health interventions with a focus on the three disorders be offered for women undergoing IPV.

Keywords: anxiety, comorbidity, depression, intimate partner violence, post-traumatic stress disorder

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Authors: Wen-Chen Hwang, Yu-Hsi Yuan

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According to the estimation made by researchers of safety and hygiene, 80% to 90% of workplace accidents in enterprises could be attributed to human factors. Nevertheless, human factors are not the only cause for accidents; instead, happening of accidents is also closely associated with the safety culture of the organization. Therefore, the most effective way of reducing accident rate would be to improve the social and the organizational factors that influence organization’s safety performance. Overview the present study is to understand the current level of safety culture in manufacturing enterprises. A tool for evaluating safety culture matching the needs and characteristics of manufacturing enterprises was developed by reviewing literature of safety culture, and taking the special backgrounds of the case enterprises into consideration. Expert validity was also implied for developing the questionnaire. Moreover, safety culture assessment was conducted through the practical investigation of the case enterprises. Total 505 samples were involved, 53 were executives and 452 were operators. The result of this study in comparison of the safety culture level between the executives and the operators was reached the significant level in 8 dimensions: Safety Commitment, Safety System, Safety Training, Safety Involvement, Reward and Motivation, Communication and Reporting, Leadership and Supervision, Learning and Changing. In general, the overall safety culture were executive level higher than operators level (M: 74.98 > 69.08; t=2.87; p < 0.01).

Keywords: questionnaire survey, safety culture, t-test, media studies

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Authors: Danielle Page

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Foregoing studies, statistics, and medical evaluations have established a relationship between Posttraumatic stress disorder (PTSD) and criminal justice involvement in Vietnam veterans. War is highly trauma inducing and can leave combat veterans with mental disorders ranging from psychopathic thoughts to suicidal ideation. The majority of those suffering are unaware that they have PTSD, and as a coping mechanism, they often turn to self isolation. Beyond isolation, many veterans with symptomatic PTSD turn to aggression and substance abuse to cope with their internal agony. The most common crimes committed by veterans with PTSD fall into the assault and drug/alcohol abuse categories. Thus, a relationship is established between veteran populations and the criminal justice system. This research aims to define the relationship between PTSD and criminal justice involvement in veterans, explore the mediating factors in this relationship, and analyze numerous court cases in this subject area. Further, it will examine the ways in which crime rates can be reduced for veterans with symptoms of PTSD. This ranges from the improvement of healthcare systems to the implementation of special courts to handle veteran cases. The contribution of this work to the field of forensic psychology will be significant, as it will analyze preexisting case studies and experimental data in an effort to improve the ways in which veteran cases are handled in the criminal justice system. Military personnel involved in the criminal justice system are a vulnerable population in need of healthcare and legislative attention, and this work will bring us one step closer to providing them with just that.

Keywords: forensic psychology, psychotraumatology, PTSD, veterans

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Authors: John Allbutt, Andrew Murray, Jonathan Ling, Thomas M. Heffernan

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Ultra-endurance events place unique physical and psychological pressures on participants. In this study, we examined the psychologically challenging aspects of taking part in a 3000 mile transatlantic rowing race using a qualitative approach. To date, more people have been into space than have rowed an ocean and only one psychological study has been conducted on this experience which had a specific research focus. The current study was a qualitative study using semi-structured interviews. Participants were an opportunity sample of seven competitors from a recent ocean rowing race. Participants were asked about the psychological aspects of the event after it had finished. The data were analysed using thematic analysis. Several themes emerged from the analysis. These related to: 1) preparation; 2) bodily aches/pains, 3) race setbacks; 4) boat conditions; 5) interpersonal factors and communication; 6) strategies for managing stress and interpersonal tensions. While participants were generally very positive about the event, the analysis showed that they experienced significant psychological challenges during their voyage. Competitors paid considerable attention to preparing for the physical challenges of the event. However, not all prospective competitors gave the same time to preparing for psychological factors or were aware how they might play out during their voyage. All Atlantic rowing crews should be aware of the psychological challenges they face, and have strategies in place to help cope with the psychological strain of taking part.

Keywords: confinement experiences, ocean rowing, stress, ultra-endurance sport

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Authors: Sung-Won Yoo, Chul-Hyeon Kang, Kyoung-Tae Park, Hae-Sik Woo

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Numerous studies were dedicated on the High Volume Fly-Ash (HVFA) concrete using high volume fly ash. The material properties of HVFA concrete have been the primordial topics of early studies, and interest shifted gradually toward the structural behavior of HVFA concrete such as elasticity modulus, stress-strain relationship, and structural behavior. However, structural studies consider small-scale members limited to the scope of reinforced concrete only. Therefore, in this paper, on the basis of recent studies on the structural behavior, 2 full-scale test members were manufactured with 7.5 m span length, fly ash replacement ratio of 50 % and concrete compressive strength of 50 MPa in order to evaluate the practicability of HVFA to real structures. In addition, 2 steel composite test members were also manufactured with span length of 3 m and using the same HVFA concrete for the same purpose. The test results of full-scale RC members showed that the practical use of HVFA on such structures is not hard despite small differences between test results and existing research results on the stress-strain relationship. The flexural test revealed very little difference between 50% fly ash concrete and general concrete in view of the similarity exhibited by the displacement and strain patterns. The experimental concrete shear strength being very close to that of design code, the existing design code can be applied. From the flexural test results of steel girder composite members, the composite behavior can be secured as much as that using normal concrete under the condition of sufficient arrangement of reinforcing bar.

Keywords: composite, fly ash, full-scale, high volume

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Authors: Marcelo Costa Cardoso, Luciano Pessanha Moreira

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In this work, the plastic behaviour of cold-rolled zinc coated dual-phase steel sheets DP600 and DP800 grades is firstly investigated with the help of uniaxial, hydraulic bulge and Forming Limit Curve (FLC) tests. The uniaxial tensile tests were performed in three angular orientations with respect to the rolling direction to evaluate the strain-hardening and plastic anisotropy. True stress-strain curves at large strains were determined from hydraulic bulge testing and fitted to a work-hardening equation. The limit strains are defined at both localized necking and fracture conditions according to Nakajima’s hemispherical punch procedure. Also, an elasto-plastic localization model is proposed in order to predict strain and stress based forming limit curves. The investigated dual-phase sheets showed a good formability in the biaxial stretching and drawing FLC regions. For both DP600 and DP800 sheets, the corresponding numerical predictions overestimated and underestimated the experimental limit strains in the biaxial stretching and drawing FLC regions, respectively. This can be attributed to the restricted failure necking condition adopted in the numerical model, which is not suitable to describe the tensile and shear fracture mechanisms in advanced high strength steels under equibiaxial and biaxial stretching conditions.

Keywords: advanced high strength steels, forming limit curve, numerical modelling, sheet metal forming

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Authors: B. Loukil, L. Mallem, M. S. Boulakoud

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Inorganic fertilizers consist mainly of salts of ammonium nitrate, phosphate and potassium, the combination of primary nutrients NPK including secondary and micro nutrients are essential for plant growth, used for intensive agriculture, ranching, and horticultural crops, to increase soil fertility and ensure sustainable crop production. The manufacture of fertilizers is generally at a high temperature and high pressure, in the presence of several highly hazardous chemicals, dust and gases. These products are absorbed high in the airway, increasing the airway resistance thereby adversely affecting the pulmonary functions of workers. A study was conducted on 34 employees, especially exposed to nitrate derivatives. A questionnaire was prepared and distributed to all employees in the unit. The workers were divided into two groups according to age. Several hormonal parameters Assay were measured. The results of the questionnaire have detected a fertility problem, Concerning the hormones a significant reduction in the concentration of testosterone in both groups and LH in the group aged 30 to 40 year were noted compared to the control. However, an increase in the concentration of prolactin in both groups compared to the control. There was a significant decrease in FSH in the group aged 30 to 40 always in compared with the control group.

Keywords: fertilizers, healthy worker, risk, fertility

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Authors: Victoria Eugenia Garnacho-Garnacho, Elena Sonsoles Rodriguez-Lopez, Raquel Delgado-Delgado, Alvaro Otero-Campos, Jesus Guodemar-Perez, Angelo Michelle Vagali, Juan Pablo Hervas-Perez

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Asthma is a heterogeneous disease which has always had a drug treatment. Osteopathic treatment that we propose is aimed, seen through a dorsal manipulation (Dog Technic D1-D4) and a technique for diaphragm (Longitudinal Stroke) forced expiratory flow in spirometry changes there are in particular that there is an increase in the volumes of the Peak Flow and Post intervention and effort and that the application of these two techniques together is more powerful if we applied only a Longitudinal (Stroke). Also rating if this type of treatment will have repercussions on breathlessness, a very common symptom in asthma. And finally to investigate if provided vertebra pain decreased after a manipulation. Methods—Participants were recruited between students and professors of the University, aged 18-65, patients (n = 18) were assigned randomly to one of the two groups, group 1 (longitudinal Stroke and manipulation dorsal Dog Technic) and group 2 (diaphragmatic technique, Longitudinal Stroke). The statistical analysis is characterized by the comparison of the main indicator of obstruction of via area PEF (peak expiratory flow) in various situations through the peak flow meter Datospir Peak-10. The measurements were carried out in four phases: at rest, after the stress test, after the treatment, after treatment and the stress test. After each stress test was evaluated, through the Borg scale, the level of Dyspnea on each patient, regardless of the group. In Group 1 in addition to these parameters was calculated using an algometer spinous pain before and after the manipulation. All data were taken at the minute. Results—12 Group 1 (Dog Technic and Longitudinal Stroke) patients responded positively to treatment, there was an increase of 5.1% and 6.1% of the post-treatment PEF and post-treatment, and effort. The results of the scale of Borg by which we measure the level of Dyspnea were positive, a 54.95%, patients noted an improvement in breathing. In addition was confirmed through the means of both groups group 1 in which two techniques were applied was 34.05% more effective than group 2 in which applied only a. After handling pain fell by 38% of the cases. Conclusions—The impact of the technique of Dog-Technic for D1-D4 and the Longitudinal Stroke technique for diaphragm in the volumes of peak expiratory flow (PEF) in asthmatic patients were positive, there was a change of the PEF Post intervention and post-treatment, and effort and showed the most effective group in which only a technique was applied. Furthermore this type of treatment decreased facilitated vertebrae pain and was efficient in the improvement of Dyspnea and the general well-being of the patient.

Keywords: ANS, asthma, manipulation, manual therapy, osteopathic

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Authors: Hanan Al-Khalaifah, Afaf Al-Nasser

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The egg shell quality and oviposition in laying hens are influenced by a range of factors including strain of birds, age, nutrition, water quality, general stress, heat stress, disease, and lighting program inside houses. A layer experiment was conducted to investigate the effect of split-phase lighting program on egg production efficiency. Four different feeds and average phosphorus (av. P) levels were tested. Diet A was a ration with an av. P level of 0.471%; Diet B was a ration with an av. P level of 0.510%; Diet C contained an av. P level of 0.293%; and Diet D contained an av. P level of 0.327%. The split-phase lighting program tested was one that inserted a 7-hour dark period from 9 am to 4 pm to reduce the heat produced by the feeding increment and physical activity of the hens. Diet B produced significantly more eggs than Diet C, or Diet D. Diet A was not significantly different from any of the other diets. Diet B also had the best feed efficiency with the other three diets in the same order and significance as for egg production. Diet D produced eggshells significantly thicker than either Diet A, or Diet B. Diet C produced thicker eggshells than Diet B, whose shells were significantly thinner than the other three diets. There were no differences in egg size. From these data, it is apparent that the minimal av. P level for the Lohmann strain of layer in Kuwait is above 0.327%. There was no difference in egg production or eggshell thickness between the split-phase light treatment and the standard light program. There was no difference in oviposition frequency. The split-phase light used 3.66% less feed, however, which was significant. The standard light produced eggs that were significantly heavier (66.30g vs. 65.73g). These results indicate that considerable savings in feed costs could be attained by using split-phase lighting, especially when cooling is not very efficient.

Keywords: egg, laying, nutrition, oviposition

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Authors: Adel Ahmadi Hosseini, Fatemeh Tavanaei, Alessandro Navarra, Ferri Hassani

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Mining engineering, as a part of geoscience, must address modern concerns. Traditional mining methods incorporate drill and blast technologies, which are followed by different issues, including excessive noise, vibration, air pollution, and safety hazards. Over the past two decades, mining engineers have sought alternative solutions to move from drill and blast to continuous methods to prevent such issues and improve sustainability in mining. Among the suggested methods, microwave treatment has shown promising results by creating micro/macro cracks in the rock structure prior to the operations. This research utilizes an energy-based analysis methodology to evaluate the efficiency of the microwave treatment in improving mining operations. The data analysis shows that increasing the input microwave energy dosage intensifies the rock damage. However, this approach can decrease the energy efficiency of the method by more than 50% in some cases. In this study, rock samples were treated with three power levels (3 kW, 7 kW, and 12 kW) and two energy dosages (20 kWh/t and 50 kWh/t), resulting in six conditions. To evaluate the impact of microwave treatment on the geomechanical behavior of the rocks, Unconfined Compressive Strength (UCS) tests were conducted on the microwave-treated samples, yielding stress-strain curves. Using the stress-strain curves, the effect of the different powers and energy dosages of microwaves are discussed. This research shows the potential of using microwave treatment to lead the industry to more sustainable mining.

Keywords: microwave treatment, microwave energy dosage, sustainable mining, rock fragmentation

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Authors: Anna K. Wood, Terri Friedline

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In April and May 2020, the private banking industry approved over 1.7 million emergency small business loans, totaling over $650 billion in federal relief funds as part of the Paycheck Protection Program (PPP). Since the program’s rollout, the extensive evidence of discriminatory lending and misuse of funds has been revealed by investigative journalism and academic studies. This study is based on 41 interviews with frontline banking industry professionals conducted during the days and weeks of the PPP rollout, presenting a real-time narrative of the program rollout through the eyes of those in the role of a street-level bureaucrat. We present two themes from this data about the conditions under which these frontline workers experienced the PPP: Exigent Timelines and Defaulting to Existing Workplace Norms and Practices. We analyze these themes using literature on street-level organizations, bureaucratic discretion, and the differences between public and private sector logic. The results of this study present new directions for theorizing sector-level differences in street-level bureaucratic discretion in the context of mixed-sector collaboration on public service delivery, particularly under conditions of crisis and urgency.

Keywords: street level bureaucracy, social policy, bureaucratic discretion, public private partnerships

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Authors: M. Afzal, Salem Safer Alghamdi, Awais Ahmad

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Limited amount of irrigation water is an alarming threat to arid and semiarid agriculture. However, genotypic response differences to water deficit conditions within species have been reported frequently. Present study was conducted in order to measure the genotypic differences among faba bean accessions under Regular Deficit Irrigation (RDI). Five seeds from each accession were sown in 135 silt filled pots (30 x 24 cm). Experiment was planned under split plot arrangement and replicated thrice. Treatments consisted of three RDI levels (100% (control), 60% and 40% of the field capacity) and fifteen faba bean accessions (two local accessions as reference while thirteen from different sources around the world). Irrigation treatment was started from the very first day of sowing. Plant height, shoot dry weight, stomatal conductance and total chlorophyll contents (SPAD reading) were measured one month after germination. Irrigation, faba bean accessions and the all possible interactions has stood significantly high for all studied parameters. Regular deficient irrigation has hampered the plant growth and associated parameters in decreasing order (100% < 60% < 40%). Accessions have responded differently under regular deficient irrigation and some of them are even better than local accession. A highly significant correlation among all parameters has also been observed. It was concluded from results that above parameters could be used as markers to identify the genotypic differences for water deficit stress response. This outcome encouraged the use of superior faba bean genotypes in breeding programs for improved varieties to enhance water use efficiency under stress conditions.

Keywords: accessions, stomatal conductance, total chlorophyll contents, RDI, regular deficient irrigation

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Authors: Robyn Jackaman

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This research explores the characterization of leadership, self-awareness, and gender identity within a higher educational institution. This is in response to the widely researched area of gender in relation to senior management levels and the contemporary reflection of this issue in leadership, where gender diversity is lacking. Through organizational platforms, the University has self-identified issues relating to gender, equality, and representation. With equality being central to the core of the project, a Community Participatory Action Research approach was implemented. This approach was chosen as it is recognized for facilitating change within community contexts which complements the University Campus culture. Seventeen semi-structured interviews gave qualitative insight into working habitus (from both professional and academic services), leadership attributions and qualities and gender significance within the workplace. The research team (cross-disciplinary) used framework analysis to code and categorized the data. Key findings presented categories in gender significance to personal/work identity, organizational change and positive reflections on leadership characteristics and roles. This research has helped support the creation of tools to better assist the organization in gender equality, inclusion, and leadership development.

Keywords: gendered work, gender equality, leadership, university organization

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