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This study investigated the potentials of face-to-face and computer mediated conversation (CMC) as two speaking modalities on students' engagement. To this end, 30 Iranian male intermediate EFL learners were selected on the basis of their performance on OPT (Oxford Placement Test) and assigned into the research groups. The progression of face- to- face and CMC groups from limited to elaborate engagement at verbal, paralinguistic and functional levels was assessed using transcription analysis in face-to-face group and chat log analysis in CMC group. The limited and elaborate student engagement indicators in two modalities were identified via Maxqda software. The results of Maxqda analysis indicated that limited engagement was associated with appeal for help, silence, pauses and hesitations, focus on syntax, involvement with procedural talk and L1 use. Respectively, elaborate engagement was associated with avoiding L1 use, focus on discourse, involvement with actual talk and strategic discourse management rather than pause and silence. Chi-square analysis on frequency of indicators of limited and elaborate engagements on verbal, paralinguistic and functional levels indicated that limited and elaborate engagements occurred with different proportions in face-to-face and CMC conversations. Teaching practitioners would benefit the findings of the study since the findings illustrate how students' engagement in learning evolves and how speaking modalities may impact the pattern of students' engagement over time. The finding also suggest one way for improving student engagement without over-intervening of teachers is using modalities such as forums where the teacher presence is limited and students have to manage the discourse themselves which in turn increases student engagement.

Food security during pregnancy is crucial for safeguarding the health of expectant mothers and optimizing prenatal outcomes. Food insecurity can manifest in varying degrees, ranging from moderate disruptions to the quality and diversity of diet to severe cases that disrupt dietary patterns and reduce overall food intake. Limited information exists regarding food security among pregnant women in Iran. Therefore, this qualitative study aims to investigate food security during pregnancy from the perspectives of pregnant women (n = 17) and experts in food security (n = 6). Data were collected through purposeful sampling and 23 semi‐structured interviews. The data analysis process occurred concurrently with data collection, employing a conventional content analysis approach. The findings underwent rigorous evaluation based on credibility, confirmability, dependability, transferability and authenticity. The results revealed that access to quality foods in pregnancy depends on the sustainability of food resources, economic access to food, the family's food budget, pregnant women's utilization of food due to pregnancy conditions, their nutritional literacy and cultural practices. Pregnant women employ various strategies to cope with food insecurity and require social and governmental support to manage it effectively. Therefore, it is suggested that health care authorities initially assess the level of food security among pregnant women and subsequently, through equitable food distribution, reform culture and increase food literacy, providing practical and informative educational programmes, and structured support, improve their food security. [ABSTRACT FROM AUTHOR]

Introduction: High-tempo music is commonly used during exercise to enhance physical activity. Postexercise parasympathetic reactivation, responsible for cardiac recovery, is crucial for predicting cardiac arrhythmia and overall heart health. Previous studies have demonstrated positive effects of music on exercise performance in healthy individuals. However, little is known about its impact on diabetic (Type II) females and young adults. Therefore, we aimed to investigate the effect of listening to high-tempo music during exercise on workout performance and parasympathetic reactivation in these populations. Material & Methods: We evaluated a total of 70 females, including healthy individuals (n=36) and diabetic (Type II) females (n=34). Prior to the experiment, lipid profile and cardiac risk ratio were measured in blood samples taken one week before the active sessions. Each participant underwent two separate active sessions: one session involved running without music, and the other involved running while listening to music for a duration of 6 minutes. Heart rate was measured before running and at zero, five, and ten minutes after exercise. Running distance was also recorded. Results: In healthy adults, running distance significantly increased when listening to music during exercise compared to the non-music session (P<0.0001). Additionally, heart rate was significantly higher at time zero during running with music compared to the non-music session (P<0.0001). However, heart rate recovery was superior 10 minutes after exercise in the music group compared to the non-music group in diabetic females (P<0.0001). Conclusion: Listening to high-tempo music during exercise may increase sympathetic activity and enhance exercise performance, particularly in healthy young adults. Interestingly, listening to music during exercise may accelerate parasympathetic reactivation to a greater extent in diabetic females, potentially reducing the risk of arrhythmias during the resting period without enhancing exercise performance. [ABSTRACT FROM AUTHOR]

Described are the synthesis and characterization of two, potentially tetradentate, N2S2 Schiff-base ligands, containing a disulfide bond, N,N′-bis(3-phenylprop-2-en-1-ylidene)-2,2′- disulfanediyldianiline (L1) and N,N′-bis(3,3-diphenylprop-2-en- 1-ylidene)-2,2′-disulfanediyldianiline (L2), and their reaction with Zn2+. Surprisingly, both L1 and L2 undergo reductive disulfide bond scission upon reaction with Zn2+ in alcoholic media to give, under alcohol oxidation, the respective Zn(NS) 2 complexes Zn(L3)2 (1) and Zn(L 4)2 (2), where the L3 and L4 are the respective bidentate thiolate-imine anions. The ligands L1 and L2 and the complexes 1 and 2 have been characterized spectroscopically, and the crystal and molecular structures of the two complexes have been determined by single crystal X-ray diffraction. The coordination geometry around Zn(II) centers in both complexes is a distorted tetrahedron. In addition, DFT calculations (B3LYP/LANL2DZ/6-311++G(d,p)) support the structure of 1. Cyclic voltammetric studies demonstrate that Zn(II) shifts the reduction potential of the disulfide ligands L1 and L2 to less negative values thus making them more susceptible to reductive cleavage of the disulfide bond. The results of semi-empirical PM6 calculations offer key insight into the nature of the transition state for this reaction. © 2014 Elsevier Ltd. All rights reserved.

The food security status of pregnant women not only affects their current health status and that of their newborn, but also plays an important role in the health status of children and adults in the future. Food security is a complicated and multidimensional concept. In pregnant women, it is the result of several complex individuals, family, social, cultural, economic, and political factors such as lack of health services, gender inequality, and lack of resources. Public instruments that mainly measure food insecurity at the household level have been used to investigate the food security status of pregnant women. Therefore, we aimed to define the concept of food security based on the experience of both pregnant women and experts, and then develop and validate the assessment tool for assessing food security in pregnant women. In this article, only the protocol of this study is discussed. This research is a mixed-method study with a sequential-exploratory approach, which will be conducted in two phases. In the qualitative phase, the concepts and dimensions of food security will be explained based on the experiences of pregnant women by using inductive content analysis. Data integrity will be guaranteed with five criteria of validity, verifiability, reliability, transferability, and authenticity. In the second phase, the primary tool will be developed based on Waltz and Basel's approach, and then it will be validated. The design of a specific tool for pregnant women, taking into account the cultural, economic, and social conditions of Iran, can be a practical solution to scientifically assess the food security status of pregnant women, so that the country's policymakers and planners can take accurate and long-term steps towards improving the food security of Iran pregnant women, their health and that of the future generations by implementing basic policies. [ABSTRACT FROM AUTHOR]

This research examines whether ultrasonic waves can enhance the hydrolysis, stability, and dewatering of activated sludge from raw urban wastewater. Sampling and physical examination of the activated sludge that was returned to the aeration pond were carried out using ultrasonic waves that were guided at frequencies of 30 and 50 kHz for periods of 0.5, 1, 3, 5, 10, 15, and 30 min. Various tests, including volatile suspended solids, inorganic solids, volatile solids, sludge resistant time, capillary suction time, total suspended solids, total solids, and volatile soluble solids, were carried out to advance further the processes of hydrolysis, stabilization, and dehydration of samples. According to the observations, the volatile soluble solids at a frequency of 30 kHz and t = 15 min were raised by 72%. The capillary suction time of 30 and 50 kHz in 1 min demonstrated a drop of 29 and 22%, respectively. It is crucial to consider that, at 10 min and the frequency of 50 kHz, the greatest efficiency was found. The 30 kHz and 1 min yielded the optimum sludge dewatering conditions. Finally, artificial neural networks (ANN) are utilized to propose predictive models for concentration, and the results were also very accurate ( M A E = 1.37 % ). Regarding the computational costs, the ANN took approximately 5% of the time spent on experiments. [ABSTRACT FROM AUTHOR]

Graphene nanosheets and Ni were used to develop oxide matrix composite coating on anodic hard coating (AHC). Anodized Al-6061-T6 alloy was Ni plated in a solution containing 50 mg l-1 graphene nanosheets. The effect of plating time on the microstructure and properties of coatings was investigated. FE-SEM, EDS, and Raman spectroscopy were used to analyze the surface morphology, cross-section, and chemical composition of composite coatings. The presence of graphene seemed to result in the refinement of the Ni matrix grain structure. Vickers micro-hardness and dry sliding wear tests were conducted on the coatings. AHC + Ni/Gr showed 60 percent higher hardness than AHC + Ni coating (160 ± 34 HV). The presence of graphene in AHC + Ni/Gr coatings reduced the wear rate and average friction coefficient compared to AHC and AHC + Ni coatings. AHC + Ni/Gr obtained after 10 min electroplating presented the lowest wear rate. The dominant wear mechanism in AHC + Ni coating was fatigue wear, while AHC + Ni/Gr exhibited abrasion and delamination. [ABSTRACT FROM AUTHOR]