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This research is devoted to developing a finite element model using Abaqus code for the computer simulation of an in-house developed and manufactured rubber bearing subjected to static vertical and cyclic horizontal loads. A high-damping rubber compound was designed. The material behavior of the rubber was assumed to be described by the hyper-viscoelastic model. Both linear (Prony series) and nonlinear (strain hardening power law) viscoelastic relationships were used in conjunction with the Ogden-Roxburgh equation to take the addition of the stress softening phenomenon or Mullins effect into consideration. The parameters of the material model were determined using MCalibration code in which an optimization technique was used, and data obtained in experiments carried out on test specimens were fitted into the selected model. The results of the simulations were compared with their corresponding experimental data carried out on the rubber bearing. The force-displacement behavior, stress and strain fields, and computed energy were presented and discussed. It is shown that the nonlinear viscoelastic model accompanied by the Mullins effect gives the best results. Moreover, the model could accurately predict the energy variations during the earthquake loading.

Abstract Regarding the important role of α-glucosidase enzyme in the management of type 2 diabetes mellitus, the current study was established to design and synthesize aryl-quinoline-4-carbonyl hydrazone bearing different 2-methoxyphenoxyacetamide (11a–o) and the structure of all derivatives was confirmed through various techniques including IR, 1H-NMR, 13C-NMR and elemental analysis. Next, the α-glucosidase inhibitory potentials of all derivatives were evaluated, and all compounds displayed potent inhibition with IC50 values in the range of 26.0 ± 0.8–459.8 ± 1.5 µM as compared to acarbose used as control, except 11f and 11l. Additionally, in silico-induced fit docking and molecular dynamics studies were performed to further investigate the interaction, orientation, and conformation of the newly synthesized compounds over the active site of α-glucosidase.

Hypothesis: In elastomeric composites, interfacial phenomena such as the effect of reinforcing filler on molecular dynamics of the rubber chain in the interphase and the way of rubber-filler interaction are the source of strain energy change or viscoelastic loss of the composite in highly filled rubber compound. To obtain a preliminary approximation of how the strain energy is influenced by interfacial phenomena, including stiffness, loss and the quality of this region, in this research, the finite element microstructural model was created in two-dimensional and three-dimensional mode and the effective characteristic changes in mechanical properties were studied. The effect of the change in stiffness of the interphase and the change in viscoelastic nature, the amount of contact between the rubber-filler in completely bonded and frictional sliding states were modeled.Methods: The solution styrene butadiene rubber composites reinforced with silica were prepared by melt mixing. For this purpose, rubber was mixed with silica and silane coupling agent in an internal mixer. Then the masterbatch was mixed with the curing system on a two-roll mill and finally the sample was cured under pressure at 160°C.Findings: In agreement with the modeling results, the composite tensile test showed that the most important controlling parameter is the type of rubber-filler connection in the interphase. The simulation results showed that considering the interphase region with frictional sliding greatly reduces the stress transfer from the matrix to the particle. But in the case of the completely bonded interphase region, due to the complete transfer of stress from the particle to the matrix, the mechanical properties showed a significant deviation compared to the experimental results. Also, the 3D models provided better predictions than the 2D ones.

Purpose: The study determines employee perception of risk management practices and organizational commitment in Private Banks of Balochistan. Earlier studies in the field highlight the importance of HR practices during organizational transition since it may be necessary to influence employee behavior to support the change's direction. By implementing HR practices that encourage change, The HR department is in an excellent position to effect positive perception. Methodology: Using a quantitative research approach, this study evaluates the relationship between employee perception of risk management practices and organizational commitment in the banking sector. Findings: The study's findings for banking sector organizations, supporting them in better understanding the elements that influence employee perceptions of risk management practices and their commitment to the organization. The study's findings could be used to design focused initiatives to improve risk management practices and increase employee happiness and organizational effectiveness. Implications: This study may provide a foundation for future research in related domains by contributing to existing knowledge on risk management and organizational commitment. Finally, the study hopes to promote a risk-aware culture within the banking sector, resulting in a more engaged and resilient workforce and boosting these organizations' long-term prosperity and stability.

The purpose of the current research was to determine the level of physical activity of the male employees of the police guard and also to investigate the relationships between physical activity and mental and social wellbeing in the male employees of the police guard. The current research was descriptive-correlation research. The statistical population of this research included all the male employees of police guard of Tehran in 2021. The statistical sample of the current research included 146 men who were selected through convenience sampling. Physical activity was measured using the international physical activity questionnaire (IPAQ), mental health was measured using depression anxiety and stress scale 21 (DASS-21), and social health was measured using the Keyes's social well-being questionnaire (KSWBQ). Pearson’s correlation test and structural equations were used for data analysis. Results showed that the research subjects had a body mass index with an average of 24.40 which is at an average level, but close to overweight. Also, a total of 52% of the subjects had moderate-to-vigorous physical activity. In addition, the mental and social health scores were in the average range. Moreover, physical activity had significant relationships with mental health and social health. The results of the model fit showed that the research model had a good fit. Our findings indicated the positive effects of physical activity on psycho-social health components in the male employees of police guard. These findings show that the use of strategies and interventions to improve the physical activity status of the staff of police guard is of special importance.

Abstract Background Previous studies have shown that CD134 (OX40) co-stimulation is involved in the pathogenesis of experimental autoimmune encephalomyelitis (EAE) models and the antigen is expressed within multiple sclerosis lesions in humans. OX40 (CD134) is thought to be a secondary co-stimulatory immune checkpoint molecule that is expressed by T cells. This study aimed to evaluate the mRNA expression of OX40 and its serum levels in the peripheral blood of patients with Multiple Sclerosis (MS) or Neuromyelitis Optica (NMO). Methods Patients with MS (n = 60), NMO (n = 20), and 20 healthy subjects were recruited from Sina Hospital, Tehran, Iran. The diagnoses were confirmed by a specialist in clinical neurology. Peripheral venous blood was obtained from all subjects, and mRNA quantification of OX40 was conducted using real-time PCR. Serum samples were also obtained and the concentration of OX40 was determined using an enzyme-linked immunosorbent assay (ELISA). Results There was a significant correlation between the mRNA expression and serum levels of OX40 and disability as assessed using the expanded disability status scale (EDSS) in the patients with MS, but not in the patients with NMO. Expression of OX40 mRNA was significantly higher in the peripheral blood of MS patients compared to healthy individuals and NMO patients (*P

The cytoskeleton is a fundamental component found in all eukaryotic organisms, serving as a critical factor in various essential cyto-biological mechanisms, particularly in the locomotion and morphological transformations of plant cells. The cytoskeleton is comprised of three main components: microtubules (MT), microfilaments (MF), and intermediate filaments (IF). The cytoskeleton plays a crucial role in the process of cell wall formation and remodeling throughout the growth and development of cells. It is a highly organized and regulated network composed of filamentous components. In the basic processes of intracellular transport, such as mitosis, cytokinesis, and cell polarity, the plant cytoskeleton plays a crucial role according to recent studies. The major flaws in the organization of the cytoskeletal framework are at the root of the aberrant organogenesis currently observed in plant mutants. The regulation of protein compartmentalization and abundance within cells is predominantly governed by the process of vesicle/membrane transport, which plays a crucial role in several signaling cascades.The regulation of membrane transport in eukaryotic cells is governed by a diverse array of proteins. Recent developments in genomics have provided new tools to study the evolutionary relationships between membrane proteins in different plant species. It is known that members of the GTPases, COP, SNAREs, Rabs, tethering factors, and PIN families play essential roles in vesicle transport between plant, animal, and microbial species. This Review presents the latest research on the plant cytoskeleton, focusing on recent developments related to the cytoskeleton and summarizing the role of various proteins in vesicle transport. In addition, the report predicts future research direction of plant cytoskeleton and vesicle trafficking, potential research priorities, and provides researchers with specific pointers to further investigate the significant link between cytoskeleton and vesicle trafficking.

It has been shown that children with mental disabilities have weaker basic motor skills than healthy children. The main aim of this study was to determine the effect of eight weeks of Spark training program on fine and gross motor skills of 6 to 8 year old male students with trainable mental disability. This research is of applied research and quasi-experimental research. By selecting the subjects from among the exceptional schools, 30 people were selected for the research. In the next stage, out of these 30 people, a pre-test was performed and 15 people in the Spark group and 15 people in the control group were randomly selected. The experimental group performed a training program selected by the Spark group for 24 sessions and 60 minutes in each session. During this time, the control group resumed its normal activities. The results showed that: Eight weeks of Spark training program has a significant effect on fine motor skills of 6 to 8 year old male students with trainable mental disability. The eight-week Spark training program has a significant effect on the gross motor skills of 6- to 8-year-old male students with trainable mental disabilities. Spark exercise program can have a significant positive effect on the gross and fine motor skills of mentally retarded children.

Hypothesis: Determination of the parameters of the material models for rubber compounds is usually carried out under simple modes such as uniaxial tension. These models are typically consisted of hyper-viscoelastic and stress-softening equations. However, due to the complicated behaviors of rubbery materials, the effectiveness and accuracy of such models under combined loads of tension, compression, and shear should be verified.Methods: Three rubber compounds were prepared based on SBR reinforced by three different amounts of carbon blacks and underwent uniaxial cyclic under two loading/unloading rates and volumetric tests. The experimental data were used for the determination of parameters of three complex material models using a nonlinear curve fitting method. These models were selected based on the results of our previous findings. We have verified the uniaxial condition of the chosen test method and sample size using finite element method. The computed parameters were employed to simulate cylindrical rubber samples prepared from the same compounds through the finite element method using Abaqus code under compressive-contact loads. The predicted results were next compared with their experimentally measured data.Findings: The results showed that the effectiveness of a material model in the prediction of stress-strain or stress-time behavior of a rubber compound under a simple load case does not necessarily guarantee that the same level of accuracy is obtained for the other loading modes, especially for highly filled compounds. It is shown here that to obtain accurate results in such cases, in addition to hyper-viscoelastic and stress softening equations, the material model should include proper terms to consider the effect of the filler-filler interactions into account, especially for highly carbon black-loaded compounds. It is found that the best model is the one in which the viscoelastic behavior of the filler-filler structure is independently included.

Background: The rapid development of modern technologies renders a convenient and efficient solution to implement Electronic Health Records (EHRs) systems. The rapid growth of healthcare data has a distinctive attribute of digital transformations. The big datasets of healthcare, their complexity and their dynamic nature have posed severe challenges associated with the analysis, pre-processing, privacy, security, storage, usability and data exchange. Material and Methods: We have performed the Systematic Literature Review (SLR) and followed the Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) methodology. SLR refers to the methodology that discovers, analyses and accesses recent research literature related to the subject field. The research papers were searched from academic repositories like IEEE, WOS, Scopus and PubMed for the previous five years on March 2023. Results: The designed search string provides 199 research articles in total. We filter the research articles based on inclusion-exclusion strategies and quality assessment metrics. Six main criteria for research inclusion-exclusion for SLR are formulated. These works of literature insight into 1) the issues associated with interoperability and security of EHRs by using the Blockchain (BC) technology, 2) different frameworks and tools to improve privacy and security in the healthcare domain, 3) the open issues of using BC technology in the electronic healthcare domain, 4) the standardized ways to store EHRs, 5) various ways to handle the big data using the BC systems and 6) the usage of Federated Learning (FL) to preserve the privacy of EHRs in the healthcare domain. We acquired 46 research articles based on the criteria (inclusion-exclusion) that investigate the above-mentioned issues. Conclusion: The SLR will serve as the state-of-the-art (SOTA) for future researchers in the field of BC in healthcare. Additionally, the paper provides insights to the new researchers to revolutionize the healthcare domain by adopting the latest digitalized technologies. The proposed study identified various reflections. It analyzed the architectural mechanism that supports the security and interoperability of EHRs. Secondly, the study described different tools and frameworks to improve the privacy and security of EHRs using the BC. Thirdly, the open issues of storing and preserving the EHRs using BC in the healthcare system were determined. Fourth, it analyzed and provided a detailed view of using standardized ways for storing and handling big data by using the BC system. Lastly, the usage of FL to preserve the privacy of EHRs was analyzed.

The aim of this study was to investigate the effects of teaching style in physical education on prosocial and antisocial behaviors of children. We used a descriptive-correlational method for this study. The participates of the present study included 384 primary school students (mean age of 9.17 years old), including 192 boys and 192 girls which were selected by using a convenience sampling method. For collecting data, teacher as social context (TASC) Questionnaire, sport climate questionnaire (SCQ) and prosocial and antisocial behavior in sport scale (PABSS) were used. Correlation test and structural equation method were used for da analysis. The results showed that perceived need support directly affected prosocial behaviors. In addition, perceived need thwarting indirectly affected prosocial behaviors. Moreover, perceived need support indirectly affected antisocial behaviors. Finally, perceived need thwarting directly affected antisocial behaviors. These findings demonstrate that needs supportive teaching style would lead to increase the prosocial behaviors and decrease antisocial behaviors in the physical education class among children.

The effects of motor imagery and physical practice on motor learning in individuals with ADHD received very little attention. Therefore, in the present study, we aimed to examine the effects of motor imagery and physical practice on motor performance and learning dart-throwing in adolescents with ADHD. The current research was based on a causal-comparative approach. The participants included 60 adolescents with ADHD (with the age range of 12 to 17 years) randomly and equally assigned into four groups: 1) motor imagery, 2) physical practice, 3) combination of motor imagery and physical practice, and 4) control. The motor task involved dart-throwing, in which the accurate throw score was measured as the dependent variable. The participants performed the pre-test (ten throws) and the retention test (ten throws). ANOVA was run to analyze the throwing accuracy. Results showed that all groups had similar throwing scores in the pretest, however, in the retention test, the results indicated that combination group had significantly better throwing scores than all other groups (in all groups, P=0.000). In addition, physical practice group had significantly better throwing scores than motor imagery and control groups (both P=0.000). Finally, motor imagery group had significantly better throwing scores than control group (P=0.000). Individuals with ADHD benefit from motor imagery, indicating that they have the necessary mechanisms to learn new skills through motor imagery. Moreover, a combination of motor imagery and physical practice would be a better strategy for learning new motor skills.

The aim of the current study was to investigate the beneficial effects of dietary thiamine supplementation on physiological, immunological and antioxidant responses in juvenile beluga, Huso huso. The juvenile fish (∼ 3 g) were fed four times a day with diets containing 0 (control), 5 (5 T), 10 (10 T), and 20 (20 T) mg kg−1 thiamine for 12 weeks. Significant increases were observed in growth performance indicators of the fish fed different levels of thiamine, compared to the control group and the best performance was observed in 10 T treatment. The carcass protein content significantly increased in the thiamine-treated fish and the highest protein content was observed in the 10 T treatment. Digestive enzymes’ activities (pepsin, trypsin, lipase, and amylase) significantly increased in the fish fed the thiamine-supplemented diets. The serum alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase activities significantly decreased in the 10 T and 20 T treatments, compared to the control group. Dietary thiamine supplementation significantly increased the serum lysozyme, alternative complement activities, and IgM level, compared to the control diet and the highest lysozyme activity and IgM level were observed in the 10 T and 20 T treatments. The hepatic superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione-s-transferase, transketolase activities of 10 T and 20 T treatments were significantly higher than those of the control treatment. The hepatic catalase activities in the thiamine-treated fish were significantly higher than that of the control fish. Contrastingly, the hepatic malondialdehyde contents of the 5 T, 10 T, and 20 T treatments were significantly lower than the control treatment. Although all the dietary thiamine levels (5–20 mg kg−1) showed beneficial effects on different tested parameters, 10 mg kg−1 was the most beneficial level and is recommended for dietary inclusion to improve the growth and health of juvenile beluga.

Introduction Radiation therapy for head and neck squamous cell carcinoma is constrained by radiotoxicity to normal tissue. We demonstrate 100 nm theranostic nanoparticles for image-guided radiation therapy planning and enhancement in rat head and neck squamous cell carcinoma models. Methods PEG conjugated theranostic nanoparticles comprising of Au nanorods coated with Gadolinium oxide layers were tested for radiation therapy enhancement in 2D cultures of OSC-19-GFP-luc cells, and orthotopic tongue xenografts in male immunocompromised Salt sensitive or SS rats via both intratumoral and intravenous delivery. The radiation therapy enhancement mechanism was investigated. Results Theranostic nanoparticles demonstrated both X-ray/magnetic resonance contrast in a dose-dependent manner. Magnetic resonance images depicted optimal tumor-to-background uptake at 4 h post injection. Theranostic nanoparticle + Radiation treated rats experienced reduced tumor growth compared to controls, and reduction in lung metastasis. Conclusions Theranostic nanoparticles enable preprocedure radiotherapy planning, as well as enhance radiation treatment efficacy for head and neck tumors.

Background: Autism is the most common disease in the spectrum of pervasive developmental disorders. The main reason for this research was to find the effect of eight weeks of braitonic training on the skill behaviors of autistic children. Materials and Methods: The present study was quasi-experimental research in terms of applied purpose and research method, which was conducted as a pre-test and post-test. Therefore, among the statistical population of the present study, which included children with autism symptoms aged 6 to 8 years, who were referred to welfare centers in Tabriz for treatment, 30 people were selected voluntarily and randomly selected in two groups of 15 people who underwent braitonic and control. Before completing the exercises, the Garz questionnaire was completed by parents. The experimental group performed Braitonic exercises under the supervision of a braitonic instructor and a psychologist in one of the multi-purpose halls of Tabriz for two sessions of 45 minutes a week for 2 months. The control group engaged in their daily activities. After the training program (post-test), both experimental and control groups were measured and completed the Garz questionnaire by parents. For inferential analysis of data SPSS 21 software at p≥0.05 as a significant level was used. Analysis of variance in repeated measures and t-tests was taken to find data. Results: Findings showed that eight weeks of braitonic training has a significant effect on the coordination, agility and reaction of children with autism. Conclusion: braitonic exercises can have a significant positive effect on the motor skills of autistic children.

Abstract A novel series of diphenylquinoxaline-6-carbohydrazide hybrids 7a–o were rationally designed and synthesized as anti-diabetic agents. All synthesized compounds 7a–o were screened as possible α-glucosidase inhibitors and exhibited good inhibitory activity with IC50 values in the range of 110.6 ± 6.0 to 453.0 ± 4.7 µM in comparison with acarbose as the positive control (750.0 ± 10.5 µM). An exception in this trend came back to a compound 7k with IC50 value > 750 µM. Furthermore, the most potent derivative 7e bearing 3-fluorophenyl moiety was further explored by kinetic studies and showed the competitive type of inhibition. Additionally, the molecular docking of all derivatives was performed to get an insight into the binding mode of these derivatives within the active site of the enzyme. In silico assessments exhibited that 7e was well occupied in the binding pocket of the enzyme through favorable interactions with residues, correlating to the experimental results.

Introduction: The study of psychological variables and factors and their role on mental health and emotional maturity may affect the mental health of individuals and society. Aim: This study examines the relationship between coping styles and job stress with emotional maturity in student-athletes. Method: The method was descriptive - correlational. The population includes all student-athletes of Islamic Azad University, Tabriz Branch in 2017-2018. Two hundred people were selected by the convenience sampling method. Subjects completed a questionnaire on coping styles, job stress, and emotional maturity. Data were analyzed using the Pearson correlation coefficient test and regression analysis using SPSS-19. Results: The results showed that there was a significant positive relationship between emotional maturity and problem-focused coping style (0.31) and a significant positive relationship between emotional coping style (-0.16) and job stress (-0.37). The regression analysis results also showed that emotional maturity could positively predict problem-focused coping style and emotion-focused coping style, and job stress negatively in student-athletes (P

Global solar radiation can theoretically be approximated in terms of tilt and azimuth of the surface regarding the impossibility of simultaneous measurement of solar radiation at various surface tilt and azimuth angles. Moreover, the random and anisotropic nature of diffuse radiation in a tropical climate makes it extremely difficult to estimate global solar radiation accurately as a function of surface tilt and azimuth angles. This study aims to develop a novel experimental and theoretical approach in the form of a computational network in order to determine a precise combined model integrated with global horizontal solar radiation to evaluate global tilted solar radiation in a tropical climate. Obtained results revealed that precisely estimation of the global tilted solar radiation was possible, by combining geometric factors for the tilted beam solar radiation, a combination of Gueymard and Louche models for the tilted diffuse solar radiation, and isotropic ground reflectance model for the ground reflected radiation, along with global horizontal solar radiation. It was observed that the accuracy of the model developed was higher for the partly sunny sky compared to the cloudy and rainy sky, estimates were more accurate on south-facing surfaces, and the model's accuracy declined with the increasing tilt angle of the surface. The statistical analysis exhibited excellent agreement between the measured data and simulation results, considering the value of normalized mean absolute error (nMAE %), normalized root mean squared error (nRMSE %), and mean absolute percentage error (MAPE %), which were in the ranges 0.22–0.94, 0.27–1.11, and 0.23–1.02, respectively for estimating global tilted solar radiation in various regions of Peninsular Malaysia, and they were respectively found in the range of 10.2–27.5%, 16.1–38.9%, and 6.0–17.8%, for evaluating the monthly optimum tilt angle towards the south, that leads to a loss of solar energy from 1.3 to 5.4 kWh/m2/year in Peninsular Malaysia. This search revealed that the experimental and theoretical approach employed in this study can be extended to more climatic regions.

Our previous microscopic observations on the wet mount of cultured Candida yeast showed release of large extracellular vesicles (EVs) that contained intracellular bacteria (∼500–5000 nm). We used Candida tropicalis, to examine the internalization of nanoparticles (NPs) with different properties to find out whether the size and flexibility of both EVs and cell wall pores play role in transport of large particles across the cell wall.Candida tropicalis was cultured in N-acetylglucoseamine-yeast extract broth (NYB) and examined for release of EVs every 12 h by the light microscope. The yeast was also cultured in NYB supplemented with of 0.1%, 0.01% of Fluorescein isothiocyanate (FITC)-labelled NPs; gold (0.508 mM/L and 0.051 mM/L) (45, 70 and 100 nm), albumin (0.0015 mM/L and 0.015 mM/L) (100 nm) and Fluospheres (0.2 and 0.02%) (1000 and 2000 nm). Internalization of NPs was recorded with fluorescence microscope after 30 s to 120 min. Release of EVs mostly occurred at 36 h and concentration of 0.1% was the best for internalization of NPs that occurred at 30 s after treatment. Positively charged 45 nm NPs internalized into >90% of yeasts but 100 nm gold NPs destroyed them. However, 70 nm gold and 100 nm negatively-charged albumin were internalized into

Introduction: Depression is one of the athletes' common problems leading to mental and physical damage. Aim: This study investigates the effect of adverse childhood experiences, psychological distress, and resilience on depression in amateur athletes. Method: The method is descriptive-analytical. The population included amateur athletes in Iran in 2021. 384 individuals were selected as the research sample based on the convenience sampling method. The data collection tool is Beck's Depression Inventory (1996), Connor & Davidson Resilience scale (2003), Pornaghash and Amini Adverse childhood experiences inventory (2019) and Kessler psychological distress scale (2000). In order to analyze the data, the statistical method of structural equations modeling was used by SPSS-20 and PLS-2. Results: The results showed that adverse childhood experiences had an effect of 0.380, resilience -0.360, and psychological distress 0.264 on depression. Conclusion: Conditions for improving athletes' resilience should be provided while managing adverse childhood experiences and psychological distress to reduce burnout. In general, according to the results, it is suggested that by holding training courses, athletes' mental and psychological empowerment are provided.

Hypothesis: The aim of this study was to propose a modified model for the prediction of a stress softening behavior (Mullins effect) in carbon black filled rubber compounds. A new equation was suggested for the calculation of the damage variable in the classical Ogden-Roxburgh model based on a previously developed kinetic equation. The parameters of the new model were assumed dependent on the first principal strain. The developed model was verified by comparison of the model predictions with experimental dataMethods: Four rubber compounds based on S-SBR and E-SBR reinforced by 40 and 60 phr carbon blacks were prepared and cured into rubber sheets. The rubber test specimens (ASTM D412 C) were cut and subjected to cyclic tensile tests at an extension rate of 500 mm/min. In order to show the stress softening behavior, three cycles were selected in a way that the maximum stretch at each cycle was increased consecutively. The volumetric tests were also carried out to determine the bulk modulus and Poisson's ratio. The finite element models of the mentioned tests were created for Abaqus code. The new model was implemented into Abaqus through a user-defined subroutine developed specifically for this research. An optimization algorithm developed in Isight code was employed to determine the parameters of themodel for the prepared compoundsFindings: Comparing the predicted force versus time and force versus displacement with their corresponding experimentally measured data and goodness of fitting for new model and classical Ogden-Roxburgh model revealed that the developed model has higher capability and accuracy in prediction of the mechanical behavior of the rubber compounds. Comparing the ratio of the computed errors between two models showed that the new model has higher accuracy with an average of 38%. Moreover it is found that there are good correlations between variation of the model parameters with rubber grades and filler contents.

Background: The style of teaching in physical education classes is very important for students’ participation in physical activity. However, the impact of teaching styles in online physical education classes during the COVID-19 pandemic is not well understood. The purpose of the current research was to investigate the associations between teaching style in online physical education with needs satisfaction, motivation, enjoyment, and intention to be physically active in adolescent students. Gender differences were also computed.Methods: The current study applied a descriptive-correlation approach. The participants were 384 high-school students (192 boys and 192 girls) from Golestan province, Iran in 2020. Data was gathered using standard questionnaires. Correlation test and structural equation modeling were used to examine the associations among variables and Mann-Whitney U test was utilized to examine gender differences.Results: Descriptive data demonstrated that boys and girls had almost identical age. Results demonstrated that perceived needs support was positively associated with psychological need satisfaction (T=12.169), motivation (T=4.467), enjoyment (T=7.257), and intention (T=4.657). Moreover, psychological need satisfaction was associated with motivation (T=7.019), enjoyment (T=5.607), and intention (T=4.230). Furthermore, motivation was associated with enjoyment (T=6.967) and intention (T=7.128). Finally, enjoyment was associated with intention to physical activity (T=15.130).Conclusion: Perceived needs support is directly associated with motivating students to be physically active during online physical education.

Introduction: In recent decades, the interest in assessing, monitoring, and improving physical and mental health has increased significantly, so that improving physical and mental function has been considered a vital goal globally. Aim: The evaluated the athlete burnout among elite coaches and its relationship with mental health. Method: The research is correlational. The population was professional male coaches in the super leagues of Basketball, Handball, Volleyball, Futsal, and Wrestling in 2021. According to the statistics of the relevant federations, there were 247 coaches and head coaches. After distributing and collecting research questionnaires, 241 people completely answered the questionnaires. Ryff Scales of Psychological Well-Being (18-item) and Athlete Burnout Questionnaire were used to collect research data. Data were analyzed using SPSS software version 20. Results: The results showed a negative and significant relationship between athlete burnout and the mental health of coaches. The results of multivariate regression analysis confirmed the inverse relationship between the components of Athlete burnout and mental health. Information related to the goodness of fit index showed that the correlation coefficient (0.361) and the coefficient of determination (0.130) indicate the fitness of the evaluated model. In other words, the relationship between predictor and criterion variables was 36.1%. Conclusion: Due to the negative effects of burnout on psychological health, it is suggested to coaches to consider the psychological injuries caused by the pressure of training and competitions and pay special attention to them as factors related to reducing mental health.

Abstract Background Multiple sclerosis (MS) and neuromyelitis optica syndrome disease (NMOSD) are inflammatory diseases of the central nervous system. The pathogenesis and treatments for these two conditions are very different. Natural killer (NK) and natural killer T (NKT) cells are immune cells with an important role in shaping the immune response. B cells are involved in antigen presentation as well as antibody and cytokine production. There is conflicting evidence of the roles of NK, NKT, and B cells in the two conditions. We aimed to compare the frequency of CD3−CD16+CD56+NK, CD3+ CD56+ NKT, and CD5+CD19+ B cells in the peripheral blood and serum Interleukin-10 (IL-10) in patients with MS and NMOSD. Methods CD19+CD5+ B, CD3− CD16+CD56+ NK, and CD3+CD56+ NKT cells were quantitated by flow cytometry in 15 individuals with Interferon-Beta (IFN-β) treated relapsing–remitting MS (RRMS), 15 untreated RRMS, and 15 NMOSD patients as well as 30 healthy controls (HC). Serum IL-10 was measured using an enzyme-linked immunosorbent assay (ELISA). Results The percentage of CD3−CD56+CD16+ NK cells in the peripheral blood of IFN-treated MS (1.81 ± 0.87) was significantly lower than for untreated RRMS (4.74 ± 1.80), NMOSD (4.64 ± 1.26) and HC (5.83 ± 2.19) (p

Existing navigation applications such as Google Maps, Apple maps provide a core service to users to find the shortest path or the path that takes the least amount of time towards a user’s destination. The applications and other research efforts have been sought to include other features such as 3D maps, neighboring facilities, traffic information, and multi-modal alternate route suggestion based on user constraints. None of these, however, take into account an important factor: “user safety while commuting”. Although the common perception of street crime is that it is primarily a problem in the third-world countries, current popular hashtags or topics (e.g. “blacklifematters”) indicate that it is now prevalent in other parts of the world as well. Even existing multi-modal alternative route recommender systems are incapable of adapting to a dynamic set of safety features, are unable to provide new safe path updates in response to real-time commuter responses, and take little or no account of historical on-road events when designing the safe algorithm. In light of the above background, we begin by developing a generic framework, namely On-road Risk Minimization Problem (ORMP). We then introduce a dynamic population-based algorithm, that we call Safe Path for Everyone (SPaFE), that solves ORMP using multi-modal historical and crowdsourced data. Finally, our extensive empirical results demonstrate that SPaFE markedly outperforms the state-of-the-art.

Chronic lymphocytic leukemia (CLL) is the clonal expansion of mature CD5+ B cells and the most common lymphoproliferative disease in adults (B1-CLL). B1 cells' anti-inflammatory effects include the production of natural IgM (nIgM) by the spleen and bone marrow, decreased inflammatory cytokines as a primary response to maintaining tissue homeostasis, and enhanced release of transforming growth factor β (TGFβ). We used the flow cytometry technique in peripheral blood from patients with CLL and multiple sclerosis (MS) to immunophenotype B cells and their subpopulations. Whole blood from CLL and MS patients, as well as healthy controls, was used to detect nIgM using the VH4-34 gene copy number and real-time RT-PCR. We found that the proportion of CD5+ B cells was significantly lower in MS patients than in the control group and that CD5+ B lymphocytes were significantly higher in CLL patients than in the control group. Compared to the control group, CLL patients had significantly higher levels of the VH4-34 gene copy number. On the contrary, MS patients had significantly lower VH4-34 gene copy number levels compared to the control group. As the number of antibodies in CLL patients increases due to the high number of B1 cells, we propose a new way to treat MS by extracting this natural antibody from the sera of CLL patients and injecting it into MS patients.

BackgroundPornography exposure, particularly among students, in Bangladesh, has increased in the twenty-first century. However, pornography exposure during the COVID-19 pandemic, when people were compelled to “stay at home” and relied extensively on the internet for all forms of activities, including academia, socializing, and communication, has remained unexplored. The present study aimed to assess the prevalence of pornography exposure among students during the third wave of the COVID-19 pandemic and to determine the associated predictors.MethodsA web-based cross-sectional study was carried out among students with certain specifications, i.e., current students at high school/college/university with access to the internet and valid social media accounts. By administering a semi-structured e-questionnaire using Google Forms, a total of 646 valid responses were retained for this study. The data were analyzed in two phases by Pearson's Chi-square and multiple logistic regression model, using IBM SPSS Statistics, version 25. The results were expressed as an adjusted odds ratio (AOR) with a 95% confidence interval (95% CI).ResultsThe findings suggest that 75.9% of students were exposed to pornography during the third wave of the COVID-19 pandemic and preferred to watch the amateur/professional genre of pornography. Pornography exposure was significantly associated with age and relationship status, as students aged 22–24 years (95% CI: 1.01–2.41; p = 0.045) and over 25 years (95% CI: 1.61–10.03; p = 0.003) were more likely to watch pornography, while married students and those in relationships (95% CI: 1.24–3.49; p = 0.006) also watched pornography during the pandemic. In contrast, students who were living alone (95% CI: 0.38–0.92; p = 0.021), were living in the Khulna division (95% CI: 0.16–0.52; p < 0.001) or had a negative attitude toward pornography (95% CI: 0.94–0.99; p = 0.002) were less likely to be exposed to pornography.ConclusionPornography exposure was higher among students in Bangladesh during the COVID-19 pandemic, and religiosity and disapproving attitudes toward pornography negatively influenced the pornography exposure. For a better understanding of the complex dynamics of socio-demographic issues with pornography exposure among students, extensive research is required for policymakers to devise appropriate strategies and interventions to ensure healthy and safe sex life for the younger population.

Solar energy is an accessible and sustainable energy source to meet the rising air conditioning demand. This study investigated the performance of solar thermal assisted sorption cooling systems, namely, solar absorption (SABC) and adsorption cooling (SADC) systems. A novel analytical approach to determine the techno-economic potential for specific climate conditions has been developed. The climatic conditions of Malaysia were used as a case study. Both cooling systems were simulated using TRNSYS coupled with VISUAL BASIC and optimized using a multi-objective optimization algorithm implemented in MATLAB. The results show that the COPchiller and collector area have the most significant impact on the performance and primary energy consumption of SABC and SADC systems. On average, 36 % and 27 % of the useful energy gain of solar collectors was converted to the cooling effect in SABC and SADC systems, respectively. Meanwhile, the minimum amount of non-renewable primary energy, the non-renewable primary energy savings ratio, and the least payback period are 0.57 and 0.39, 7.6 % and 7.5 %, and 4 and 9 years, for the SABC and SADC systems, respectively.

Background: New mutations of COVID-19 and a lack of adequate vaccination necessitate finding certain methods to enhance mental health of adolescents during the pandemic. The present study aimed to investigate the effects of Cognitive-Behavioral Therapy on mental health of adolescents during COVID-19 pandemic. Methods: The present research applied an experimental design with pretest and posttest in 2020. The subjects herein included 65 high-school students, randomly divided into the intervention and control groups. The intervention group received three months of intervention based on Cognitive-Behavioral Therapy while the control group performed regular daily activities. Depression, anxiety, and stress were measured using standard questionnaires before and after the intervention as well as three months later. Independent t test and ANCOVA were utilized for data analysis. Results: At the baseline, 58 students (89.2%) had moderate depression, 37 students (56.9%) had severe anxiety, and 45 students (69.2%) had moderate stress. No significant differences were observed between the groups at the baseline (all P>0.05). Following the intervention, 53 students (81.6%) had moderate depression, 37 students (56.9%) had moderate anxiety, and 31 students (47.7%) had moderate stress. These results remained almost the same in the follow-up test. Moreover, Cognitive-Behavioral Therapy significantly reduced depression (p

Increasing demand for energy, pollution from fossil energy consumption and global warming are the key factors that have made optimal energy management necessary. The advent of information technology has led to the emergence of a new paradigm called the Internet of Energy (IOE). IOE is a new concept that provides the tools needed for optimal energy management. IOE has expanded dramatically with the advent of the Internet of Things (IOTs). So that the Internet of Energy moves towards energy management by integrating the features of smart grids and the Internet of Things. The present study is an applied research that aimed at conceptualizing of the Internet of Energy. In order to achieve the research objectives, a series of indicators of IOE were identified according to the previous studies and interviews with experts. The pattern of causal relations of these indices has been identified by the FUZZY DEMATEL technique. Then, these factors have been analyzed by Interpretive Structural Modeling (ISM) technique, and finally, the relationship and sequence of the indices have been obtained. Among the indicators, existence of powerful internet servers in the country, equipping consumable equipment with internet and online monitoring of each person’s energy consumption are at the first level of the research model and the most basic variables in applying the concept of IOE. All of these elements ultimately depend on the availability of financial resources and the determination to apply IOE at the macro level. The insight that this model provides to the energy management at the macro level can be helpful in strategic planning for energy production, conversion, transmission, distribution and consumption in the country.

The presence of employees in the workplace, despite the signs and symptoms of the disease, represents the phenomenon of presenteeism, the lack of control over which is related to the obvious and hidden costs, such as depression, burnout, deteriorating health. The present study aims to design a conceptual model for the managing presenteeism in organizations’ human resources with the approach of the grounded theory. This study, which is a kind of quality-research strategy and was by grounded theory approach, has been conducted. The statistical population of the study is employees and managers of private companies in the industrial city of Rasht. In this study, purposeful sampling was used to select the sample, which according to the saturation rule, was obtained in the present study using 25 important interviews and continued for up to 30 interviews to be more reliable. Open, axial, and selective coding methods were used to analyze the collected data. The results of the research include identifying causal factors at two levels, contextual conditions at three levels, intervening conditions, strategies and consequences of the presenteeism, and finally designing a model of managing presenteeism. Awareness of the nature of presenteeism helps to find the problem root for the implementation of strategies and mechanisms to overcome the negative consequences of presenteeism and increase the general index of health and productivity.

Abstract Effects from nonstandard corrections to Newtonian gravity, at large scale, can be investigated using the cosmological structure formation. In particular, it is possible to show if and how a logarithmic correction (as that induced from nonlocal gravity) modifies the clustering properties of galaxies and of clusters of galaxies. The thermodynamics of such systems can be used to obtain important information about the effects of such modification on clustering. We will compare its effects with observational data and it will be demonstrated that the observations seem to point to a characteristic scale where such a logarithmic correction might be in play at galactic scales. However, at larger scales such statistical inferences are much weaker, so that a fully reliable statistical evidence for this kind of corrections cannot be stated without further investigations and the use of more varied and precise cosmological and astrophysical probes.

In this study, the effects of mixture of dietary nano-selenium, vitamin C and E on growth indices, liver enzymes and nonspecific immune response of juvenile Huso huso were investigated. One hundred and twenty individuals juvenile Huso huso with average weight of 77.77 ± 2.3 g were fed with four diets including treatment A (TA by adding 0.1, 30 and 100 mg/kg), treatment B (TB by 0.2, 60 and 200 mg/kg), treatment C (TC by 0.3, 90 and 300 mg/kg) and control group (without adding nano-selenium, vitamin C and E) for 10 weeks. At the end of the rearing period, blood samples were taken from fish to evaluate liver enzymes and immune system indices. No significant differences were observed in growth indices, feed conversion ratio and protein efficiency ratio (p>0.05). The lowest activities of ALT and AST were found in TA and TB (p>0.05). However, IgM and ACH50 levels were significantly higher in TB and TA than in control group, respectively (p

Extended Spectrum beta lactamase producing pathogens are reported in many clinical samples and pose an emerging threat health. To find the prevalence of ESBL producing Enterobactriacea pathogens isolated from inpatients (Medical and Surgical Wards; Hospital stay > 72 h) admitted to Prince, Mutib, Hospital Sakaka, Jouf. A total of 1043 Enterobactriacea were isolated during April 2015 to October 2016 study period. Vitek -2 compact (biomeriux Leon, France) was used for identification and antimicrobial sensitivity (AST) test. A Total of 115/1043 (11.02%) ESBL producing pathogens were isolated from urine 15.07% (n=242), sputum 13.6 % (n=220), wound 10.8% (n=287) and blood 5.4 % (n=294). Klebsiella pneumonia is most dominant followed by E coli and Proteus miribilis. Cephamycins and carbapenems were found most effective (100% sensitivity) against the pathogens isolated. The aminoglycosides, beta lactams and Fluroquinolnes class of antibiotics, microorganisms have gained the resistance of 20%, 22.7%, 40-70% respectively. The infection control measures should be taken seriously and making of effective use of antibiotics is need of hour.

Background: In recent years, research has witnessed an exciting change toward well-being and health instead of emphasizing disorders and inefficiency. The current study aimed to assess the effect of a mindfulness-based resilience training program on the psychological well-being of medical students during the COVID-19 pandemic. Methods: The current study was quasi-experimental with a control group and a pre/post design. A sample of 30 students was randomly selected from a community of medical students at the Tabriz University of Medical Sciences in the academic year 2021-2022. These students were randomly divided into two groups of 15 participants. The tools used in this research included Ryff’s Psychological Well-Being Questionnaire (PWB-18) and an integrated training program for resilience and mindfulness. Results: The findings showed an integrated training program of resilience and mindfulness positively affected students’ psychological well-being. In addition, this intervention was able to explain 59% of the combined variance of psychological well-being variables. Conclusion: The results of the current study found that an integrated training program of resilience and mindfulness can improve individuals’ psychological well-being during a difficult situation such as the COVID-19 pandemic.

This study aimed to investigate the impact of the hospital information system (HIS) on nurses' satisfaction in Iranian public hospitals and to examine the moderating effect of computer literacy. The study population consisted of nurses working in public hospitals in Iran. A sample of 385 Iranian public hospitals was surveyed and a total of 1912 questionnaires were collected over 9 months. The analytical method used to empirically test the proposed hypotheses was the SEM technique using SmartPLS3. Results showed that all four variables of nurses' attitude, system quality, information quality, and service quality had significant positive effects on nurses' satisfaction with HIS. The findings also indicated that the effects of nurses' attitude, system quality, and particularly service quality increased on nurses' satisfaction with HIS by rising computer literacy, and only the effect of (computer literacy × information quality) was not significant on satisfaction. The use of FIMIX, CTA, and permutation test analyses is the innovation of the analysis.

Hypothesis: A three-component material model based on the combination of three hyper-viscoelastic equations,eight-chain constitutive equation, Bergstrom-Boyce relation and Ogden-Roxburgh stress softening model (Mullins effect) was selected to study the mechanical behavior of various SBR/CB (carbon black) filled rubber compounds.Methods: Three rubber compounds based on E-SBR were prepared using different carbon black contents (20, 40 and 60 phr) and cured into rubber sheets. The rubber test specimens (ASTM D412 C) were then cut and underwent cyclic tensile tests at two extension rates of 500 and 100 mm/min. In order to show the stress softening behavior, three cycles were selected in a way that the maximum stretch at each cycle was increased consecutively. The volumetric tests were also carried out to determine the bulk modulus of the samples. The stress-strain data were calibrated using MCalibration software in which three different optimization algorithms were utilized to compute the parameters of the models. Findings: Very good agreements were found between experimentally measured and predicted stress-strain data for low and medium CB filled compounds. However, for highly filled compounds there were some discrepancies at higher extensions, which may be due to the formation of a strong filler network and percolation threshold. This indicates that we may need another modeling component to be incorporated into main model for the description of the mechanical behavior of the filler-filler network itself. Moreover, it is found that there is good correlation between variation of the model parameters and filler content.

Hypothesis: Polyamide 6 (PA6)/nitrile butadiene rubber (NBR) thermoplastic elastomer reinforced by nanoparticles has several applications in various industries. The addition of nanoparticles to thermoplastic elastomers will affect the tensile strength, impact strength, fracture mechanism and thermal properties of nanocomposites. There are different processes to fabricate these nanocomposites such as extruder, internal mixer, and friction stir process.Methods: PA6/NBR/clay nanocomposites were fabricated by internal mixer (IM) and friction stir process (FSP). The mechanical properties and fracture mechanisms of these nanocomposites were investigated by mechanical testing (tensile, impact, and hardness) and essential work of fracture (EWF) methodology. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate the morphology of samples.Finding: The results indicated that with addition of nanoclay up to 5% in an elastomer containing internal mixer, the tensile strength increased, and beyond 5%, the tensile strength decreased. The friction stir process sample with 7% nanoclay showed a maximum tensile strength of 35.4 MPa. In the friction stir process sample with 7% nanoclay, the tensile modulus and total work of fracture, respectively, increased by 75% and 56%, while in the internal mixer sample, the modulus increased by 50% and total work of fracture decreased by 5%. With the addition of 7% nanoclay to PA6/NBR blend, the impact strength of friction stir process and internal mixer samples decreased by 4 and 18%, respectively. The addition of 7% nanoclay to PA6/NBR blend with friction stir process improved the thermal behavior as the crystallization temperature and melting temperature increased from 195.3 to 197.1°C and 221.3 to 222.5°C, respectively.

Background: There are some antibodies which are present in healthy individuals without any former exposure to foreign antigens; they are known as natural autoantibodies (NAAbs). In recent years, it was shown that they probably contribute to the homeostasis of the whole body and might be present before beginning of some diseases. Thus, as new biomarkers, they are promising factors to diagnose diseases. Materials and Methods: In this study, we drew upon samples of 924 individuals (600 controls and 324 cases) with underlying diseases of anemia, polycythemia, leukocytosis, thrombocytopenia, thrombocytosis, and pancytopenia. For detection of NAAbs against red blood cell, plasma samples were incubated with their own red cell suspension in 4°C for 18 h. Then, positive samples were evaluated for antibody screening and titration. Results: Fifty-two (8.6%) controls and 58 (17.9%) cases showed positive reaction (Pv < 0.001). The prevalence of positive antibody screens among auto-positive controls was 53% and 100% among cases; moreover, strength of antibody screen reaction had a mean rank of 22.5 in controls and a mean rank of 38.5 in cases (Pv < 0.001). A significant relation was also observed between ABO blood group and prevalence of NAAbs in controls but not in cases (Pv < 0.05). Conclusion: The prevalence and potency of NAAbs increased along with hematological changes; moreover, the antibody reactions' pattern and titration showed significant differences between the two groups and these may be useful as biomarker for monitoring and prediction of some hematological diseases.

Background: Finding behavioral changes in youth during the COVID-19 pandemic may provide a better image of the negative impact of quarantine on their mental and physical health. The purpose of the present research was to examine the smartphone usage status, sleep pattern, health-related quality of life, and physical activity among adolescents from before to during the COVID-19 confinement. Methods: The present study used a descriptive-comparative design. The participants were 384 male and female students aged 16 to 18 years (mean age of 16.84±1.06 years) in grades 11 and 12 from the high-schools of Golestan province, Iran, in 2020. Screen time, sleep pattern, health-related quality of life, and physical activity were measured using standard questionnaires. Paired-Sample t test was employed to compare the means of the constructs of the study from “before” to “during” the COVID-19 pandemic. Independent t test was used to measure gender differences. Results: Results shed light on the increments in smartphone use and decrements in sleep quality, health-related quality of life, and physical activity among adolescents from “before” to “during” the COVID-19 pandemic (all p 0.05). Conclusion: The findings of this study revealed the effects of policies related to COVID-19 pandemic on health-related behaviors among adolescents and emphasized the importance of adopting appropriate coping strategies to promote healthy lifestyle during confinement.

A data buoy for measuring coastal wave-action has been designed and constructed. The buoy is essentially a 0.6 m diameter sphere that is made of fiber-glass with aluminum, steel and polymer parts. While the overall geometry of the buoy is superficially similar to that of existing commercial spherical buoys (e.g. Wave-Rider by Datawell), the present design is based on a simple robust structure and mass-market electronics. A significant dual-use feature of this design is that the structure is usable as a float in a wave-energy generation device. This is possible due to the essentially isolated central structure and an electronics enclosure that is sealed both from the external environment and from the bulk shell of the buoy. This also allows the electronics to be mounted in an easily- modified, rack configuration that can be removed from the buoy shell. In a wave-energy generation set-up the electronics rack would be removed and the central cylinder will become part of a linear-motion type generator, with at least +/- 25 cm of internal movement available to it that is waterproof (for near surface or shallow immersions). Alternatively, for large wave motions, the buoy can couple to an energy-generating device using flanges that mate with its bolt circle pattern. However, at the moment, the buoy enclosure is dedicated to wave-action measurement, i.e., a data buoy with an onboard inertial measurement unit (IMU) and a radio-link to send real-time data to a receiving unit that can be on a boat or at the seashore. Basic GPS data are also transmitted. This is of interest if the buoy is being deployed in a drifting (un-moored) mode. This paper will only discuss the mechanical design and fabrication of the structure.

Background: An important issue for pediatric health is to understand how to enhance the level of physical activity of children and adolescents during the pandemic. The present study aimed to investigate the effects of a physical education- based online intervention on promoting motivation and physical activity of adolescents during the COVID-19 pandemic. Methods: The present study used an experimental design with pre-test and post-test conducted in Iran, 2020. The participants were 68 high school students who were randomly allocated into intervention and control groups. The participants of the intervention group were exposed to a three-month intervention based on Self-Determination theory within the online physical education classes while those in the control group followed their regular online physical education classes. Perceived autonomy support, motivation, intention, and physical activity behavior were measured using standard questionnaires. Independent t test and analysis of variance (ANOVA) were utilized to analyze the data. Results: The pre-test showed that the participants of both groups had similar perceived autonomy support, motivation, intention, and physical activity behavior at baseline. However, the participants in the intervention group reported higher perceived autonomy support (3.2 vs. 1.48, p

The application of residues of agricultural products as low-cost biosorbents for removing heavy metal from water, is particularly appropriate for developing countries. This study was conducted to compare the removal efficiency of lead (Pb (II)) from aqueous solutions with initial concentration of lead (0- 100 mg/L) by some raw (unmodified) biosorbents (sunflower stalks, wheat straw and corn stalks) and chemically modified of these biosorbents with NaHCO3 0.5 mol/L and NaOH 0.5 mol L. Also in this study, lead adsorption isotherms and lead removal efficiency by these biosorbents was investigated. Biochemical composition analysis of the studied biosorbents showed that sunflower stalks had the highest cellulose, lignin and ash content. Hemicellulose were highest in wheat straw but lowest in sunflower stalks. Langmuir and Freundlich models had a better fitness than the Temkin model for removal of lead by unmodified and modified biosorbents. The removal efficiency (RE) for unmodified sunflower stalks, wheat straw and corn stalks were obtained 94-99%, 85-97% and 55-95%, respectively. Also, by modification of biosorbents with NaHCO3, the removal efficiency (RE) of sunflower stalks, wheat straw and corn stalks were 94-99%, 85-97% and 55-95%, respectively. Maximum mono layer adsorption (qmax) of modified sunflower stalks, wheat straw and corn stalks increased 293, 305, 394 and 226, 265 and 363 percent compared to unmodified biosorbents, respectively. Separation factor of Langmuir (RL) increased from 0.014-0.73 (for unmodified biosorbents) to 0.065-0.93 (for modified biosorbents by NaHCO3) and 0.023-0.56 (for modified biosorbents by NaOH), indicated that the sorption reaction of lead by studied biosorbents are favorable. Chemical modification of the biosorbents with NaHCO3 could significantly increase the efficiency and capacity removal of lead from aqueous solutions. The ease of preparation of these chemically modified low-cost biosorbents and its high removal capacity for lead makes these biosorbents a good practical candidate for removal of lead from aqueous solutions.

Organizational cynicism is one of the negative organizational behaviors that results from not having the necessary information in the organization. Organizational leaders play an important role in clarifying information and staff empowerment. Authentic leadership is one of the ethical leadership approaches that leads to improved employee empowerment and reduced organizational maladaptive perspectives. The purpose of this study was to evaluate the impact of perceived authentic leadership on organizational cynicism by mediating structural empowerment in Pars Hayan employees. The research is descriptive-survey and the statistical population includes all the employees of Pars Hayan branch across the country with an estimated sample size of 200 people. Data were collected using a questionnaire whose reliability was confirmed by Cronbach's alpha and composite reliability and its validity was confirmed by content validity and convergent and divergent validity. Structural equation modeling with partial least squares approach was used for data analysis by Smart PLS software. According to the study sample, the findings of the study showed that . Authentic leadership had a significant effect on structural empowerment and organizational cynicism, and structural empowerment had a significant effect on organizational cynicism. The mediating role of structural empowerment on the impact of perceived authentic leadership on organizational cynicism was also confirmed. In fact, it can be said that by promoting perceived structural empowerment and authentic leadership, the level of organizational cynicism in Pars Hayan Company decreases.

Abstract In this paper, we analyze the clustering of galaxies using a modified theory of gravity, in which the field content of general relativity has been be increased. This increasing in the field content of general relativity changes the large distance behavior of the theory, and in weak field approximation, it will also modify the large distance behavior of Newtonian potential. So, we will analyzing the clustering of multi-component system of galaxies interacting through this modified Newtonian potential. We will obtain the partition function for this multi-component system, and study the thermodynamics of this system. So, we will analyze the effects of the large distance modification to the Newtonian potential on Helmholtz free energy, internal energy, entropy, pressure and chemical potential of this system. We obtain also the modified distribution function and the modified clustering parameter for this system, and hence observe the effect of large distance modification of Newtonian potential on clustering of galaxies.

Background and Objective: A prerequisite for the implementation of human resources excellence plans is that managers have the necessary competencies. This study aimed to identify the key competencies of managers for the excellence of human resources. Methodology: In this study, a sequential mixed method (qualitative-quantitative) research design was implemented in three steps. The grounded theory (GT) was employed in the first step to identify managerial competencies by interviewing 18 managers of 8 home appliances manufacturing companies in Iran. The Delphi method was then used in the second step to determine the importance of each competency. After that, the partial least squares structural equation modeling (PLS-SEM) technique was employed to evaluate the effects of these competencies on the results of human resources excellence in the third step where 114 intra-organizational departments and their managers (114 individuals) were monitored through the complete enumeration method. Findings: Regarding the effectiveness of establishment of a human resources excellence system, 16 key competencies were identified for managers in five areas of individual, communicational-social, management and leadership, strategic, and complementary competencies. Conclusion: Enabling managers to benefit more from these key competencies can help facilitate the progress of human resources excellence plans in organizations.

In this study, the seismic inter-story drift of structures is estimated by a combination of mode-acceleration equations with the modelling of high-rise buildings with flexural and shear cantilever beams. In the equation presented for calculating the inter-story drift, having less knowledge of the building is adequate and this issue is of significance in estimating the nonstructural component forces, especially in high-rise buildings and also in the initial design of structures. Also, a comparison of inter-story drift estimated by the approximation method with an exact method indicates that the application of the mode-acceleration method compared to mode-displacement with a fewer number of modes comes close to the exact calculation, which facilitates and expedites the analysis. In order to carry out an exact evaluation of the presented equation, inter-story drift is calculated and compared in 10, 15 and 50 story buildings during three seismic records using approximate relations. Exact analysis of those structures is done in finite element Opensees software. The results of comparisons show that the presented equation provides an adequate estimation without the need for modelling and lengthy software analysis.

Hypothesis: Reduction of rolling resistance in tyres plays a crucial role in reducing global warming and CO2 emissions. Consequently, the prediction of energy dissipation in tyre tread compounds has received increasing interest from tyre manufacturers to design low dissipative compounds. In the present work, a triple model based on the Ogden hyperelastic equation, Bergstrom-Boyce nonlinear viscoelastic relationship in conjunction with a stress softening equation was proposed for the prediction of the force-displacement behavior of tread compounds.Methods: Two series of rubber blends compounds based on SBR/BR solution and SBR/BR emulation reinforced by two carbon black (CB) grades and a surface-modified silica were prepared. Each series was comprised of three blends with different filler contents. The total part of filler in each compound was kept constant as 80 phr. The first compound contained 80 phr of CB without any silica, while the second and third compounds were prepared using 20 and 40 phr silica as replacement. The mechanical behavior of the cured compounds was determined using a tensile test carried out on a ribbon type sample with 2X11 cm dimension and ATM D-412 C test specimens. An optimization loop was designed in Isight code using three Abaqus, data matching and optimization components. The developed algorithm was used for the determination of the parameters of the mentioned model.Findings: It is shown that the proposed material model and the developed numerical algorithm can predict the mechanical behavior of the compounds during a loading/unloading cycle. The trends of the variations of the predicted parameters are in reasonable agreement with macro- and micro- structure of the SBR and filler type (CB or silica). It is also found that the addition of silica to rubber compound has 25-35% decreasing effect on energy dissipation. Moreover, solution SBR has approximately 50% more reduction effect on energy dissipation compared to emulsion SBR at equal filler type and content.

Context: Periodontally accelerated osteogenic orthodontics (PAOO) combines alveolar corticotomy, bone graft materials, and the application of orthodontic forces for rapid correction of malocclusions. Aims: The present study aims to primarily assess differences in orthodontic treatment duration, bone quality around corticotomy sites, postoperative healing, and subjective pain when corticotomy was done conventionally and with the placement of recombinant human bone morphogenetic protein-2 (rhBMP-2). Settings and Design: Thirty individuals participated in this study. Individuals were randomly assigned into each of the following experimental groups; C + BMP: Corticotomy with 0.5 μg/mL rhBMP-2 and C: Corticotomy only. Materials and Methods: Clinical parameters included recording the duration of the treatment period, visual analog scale scores and early wound healing index scores. The evaluation of bone density was performed at baseline, 3 months, and 6 months by using RVG. Statistical Analysis Used: Two-way analysis of variance and post hoc multiple comparison tests were used to compare data between test and control groups at different time points. Results: rhBMP-2 application was effective in reducing the overall treatment time and resulted in an increase in bone density around corticotomy sites at the end of the treatment period when compared to conventional corticotomy procedure. Placement of rhBMP-2 neither delayed wound healing nor affected participant pain scores. Conclusions: From this trial conducted over a period of 6 months, rhBMP-2 has the potential to function as a regenerative material in PAOO.

The reclaiming process of ethylene-propylene-diene monomer (EPDM) using a twin-screw extruder was studied and the effect of reclaiming conditions including screw speed (40, 80 and 120 rpm) and reclaiming agent content (0, 1.5 and 3 phr) at 280 °C (barrel temperature) on swelling, curing, mechanical properties as well as stress relaxation of virgin EPDM/40 phr reclaimed rubber blends was evaluated. According to the results of swelling test, the reclaiming process led to both crosslinks breakage and main chain scission. The appropriate reclaiming conditions were determined as the highest screw speed (120 rpm) and reclaiming agent content (3 phr). Compared to virgin EPDM vulcanizates, the curing behavior of prepared blends showed that the addition of reclaimed rubber had no effect on the scorch time but increased the optimum cure time and decreased the cure rate index. The results obtained for mechanical properties demonstrated that the tensile strength, modulus at 100% and 200% elongation and hardness decreased while the elongation at break of the blends showed no particular trend. The analysis of stress relaxation behavior using the Generalized Maxwell Model (GMM) revealed that the initial and final moduli of all blends decreased, and surprisingly the relaxation times were shorter or showed no change compared to the reference sample. Further, the Dynamic Mechanical Thermal Analysis (DMTA) results exhibited that the Tg of blends decreased but the maximum loss tangent presents no change following the addition of 40 phr reclaimed rubber to the virgin EPDM. Finally, the frequency sweep test indicated that the storage modulus of all blends was lower than that of the virgin sample.