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As women in the Israeli Defense Forces (IDF) are increasingly placed in supportive and combat roles in active war zones, they routinely encounter and participate in violent acts. This study focusses on the centrality of gendered inequality and oppression as a factor that shapes not only women’s experience in the military but also their responses in cases of excessive violence. The goal of this study was to explore the ways women veterans of combat or combat-support units conceptualize their stance regarding violent acts which they either committed or witnessed in war zones. Using a qualitative approach, we analyzed the retrospective testimonies of 58 Israeli women veterans from the archives of an NGO that documents veteran combatants exposure to excessive violence. Most women explained their violent acts as inherent to the military system and culture, which in our analysis was categorized as examples of either internalized gender oppression or as identification with the aggressor. A smaller number of women described their attempts to protest, as they took a moral stance rooted in a feminine perspective. The three explanations revealed through the analysis of the testimonies reflect the inner tension experienced by many women in the military, as they navigate between two extreme positions, either as victims of male dominance, or as aggressors that are part of a powerful military system. In this study, gendered inequality provides a framework for analyzing the data. Thus, this study contributes to the theoretical knowledge and methodological approaches concerning violent situations in combat areas, focusing on the various ways in which women veterans subjectively and retroactively conceptualize their participation in and responses to violent acts.

Study aim: To examine the association between accelerometer-measured physical activity (PA) and balance performance among children with considering motor self-efficacy as a mediator.

Study aim: This study aims at examining the impact of Mindfulness and mental skills on competitive anxiety in athletes.

Study aim: The purpose of the present study was to investigate the effects of observing the real, animated and combined model demonstrations on cognitive and motor learning of a basketball jump shot.

Background: Finding the factors that may affect performance of fine and gross motor skills in children with attention deficit hyperactivity disorder (ADHD) is of great importance. Therefore, the aim of this study was to examine the correlations between physical activity (PA) participation and anthropometric features with gross and fine motor skills in school children with ADHD. Methods: This was a descriptive-correlational study. The study participants were 320 students with ADHD (including 120 girls; mean age of 7.86±0.89 years) from Tehran, Iran, in 2023. To assess PA, anthropometric features and motor proficiency, the Rapid Assessment of Physical Activity (RAPA) scale (scores range from 0 to 7), standard tools such as a meter and scale, and the short form of the Bruininks-Oseretsky Test of Motor Proficiency (scores from 0-53, and 0-51 for gross and fine skills, respectively) were used. The data were analyzed using independent t-test and Pearson correlation test. Results: The participants had a relatively low level of PA (mean=2.23±1.07). Moreover, boys exhibited significantly higher proficiency in gross motor skills compared with girls (t=6.282, P<0.001), while girls demonstrated significantly higher proficiency in fine motor skills (P<0.001). Also, PA was directly and significantly associated with both gross (r=0.593, P<0.001) and fine motor skills (r=0.478, P<0.001). Moreover, body mass index showed an inverse and significant correlation with gross motor skill (r=-0.681, P<0.001). Conclusions: These findings emphasized the importance of promoting more PA and height-to-weight matching processes for optimal motor growth in children with ADHD. Therefore, it is recommended to incorporate programs aimed at enhancing motor skills in children during physical education lessons. [ABSTRACT FROM AUTHOR]

Study aim: The purpose of this research was to examine the effects of different times of day on static and dynamic balance performance.

There are many reasons why individuals are motivated to participate in sports. For athletes to participate in and keep up exercise, investigating the participation motivation of athletes is necessary. The aim of this study was to compare sport participation motivation of athletes in team and individual disciplines. The sample consisted of 265 athletes including four teams from football, volleyball, basketball, and handball and two individual disciplines of kung fu and taekwondo which were randomly selected. The 30-item sports participation motivation questionnaire (PMQ) was used. Analysis of data was conducted by the use of independent-samples t-test. The results showed that there is a significant difference between the sports participation motivation of athletes in a team and individual sports as well as between male and female athletes. But, among the components of the sports participation motivation, only the aspect of achievement in a team and individual sports and the aspect of finding friendship in male and female athletes existed, no other significant difference was observed. The results of this study show that sports discipline and the athlete’s gender is effective in motivating athletes’ continuation and commitment to a physical activity.

Study aim: The purpose of this study was to examine the effects of adopting an external focus of attention on motor learning among girls with ADHD aged seven and eleven years.

Study aim: External focus of attention is considered as a critical factor in the OPTIMAL theory of motor learning. This theory proposes that external focus of attention facilitates motor performance and learning because it promotes focusing on the task goal. However, the effects of external focus of attention on focusing on the task goal are not well understood. The aim of this study was, therefore, to investigate the effects of an external focus of attention versus an internal focus of attention on motor learning and promoting focus of the learner on the task goal.

Despite its importance, physical literacy has received scant scholarly attention, notwithstanding the obvious link between physical activity and health promotion (including but not limited to mental health). The purpose of this study was threefold: first, to explore the self-perceived physical literacy, the self-reported physical activity, and the mental health status of adolescents who study in secondary education schools in Cyprus and the potential association of those variables; second, to explore any potential statistically significant gender differences across the variables under examination; and third, to explore whether there is a mediating role of physical activity in the relationship between adolescent Cypriots' physical literacy and their mental health in the post-quarantine period. A total of 285 students, aged 13–18, from regular middle and high schools in Cyprus participated in this study. Physical literacy was measured using the Perceived Physical Literacy Instrument (PPLI). The Depression, Anxiety, and Stress Scale-21 (DASS-21) was utilized to measure mental health status. Physical activity was measured using the Physical Activity Questionnaire for Adolescents (PAQ-A). Independent sample t-tests were computed to analyze gender differences. The Pearson correlation test was used to compute bidirectional associations between research variables. Structural equation modeling was used to assess structural associations between research variables. The findings revealed statistically significant differences among boys and girls on depression (p = 0.0032), anxiety (p = 0.008), and stress levels (p = 0.003). Statistically significant and negative correlations had been found among PL and depression, anxiety, and stress levels (all p < 0.001), while PL was significantly and positively associated with physical activity (p < 0.001). Despite having only indirect effects on mental health (b = 0.51, T = −10.11, p < 0.001), physical literacy was found to have substantial direct effects on physical activity levels (b = 0.46, T = 8.66, p < 0.001). In addition, physical activity has significant indirect effects on mental health (b = 0.19, T = 5.48, p < 0.001). In summary, physical activity has significantly mediated the associations between physical literacy and mental health. Given these findings, it is important to put strategies in place to build up physical literacy and increase physical activity among Cypriot adolescents. [ABSTRACT FROM AUTHOR]

Background: Self-reported instruments have suggested that physical activity correlates with motor proficiency in children. However, due to inherent biases and low accuracy of self-reported instruments, this study aimed to investigate the relationship between objectively measured physical activity (via accelerometer) and motor proficiency in children. Methods: This study is a descriptive-correlational investigation involving 384 children (comprising 192 boys and 192 girls), aged 7 to 9 years (with a mean age of 7.96±0.73 years). These participants were in the first and second grades from regular primary schools in Tehran, Iran, during 2022, and were selected through a convenience sampling method. We employed the ActiGraph wGT3X-BT accelerometer for an objective measurement of physical activity. The Bruininks-Oseretsky Test of Motor Proficiency's short form was used to evaluate the children's motor proficiency. Data were analyzed using Independent t-test, Pearson correlation test, and multiple linear regression analysis. Results: The children did not meet the WHO guidelines recommending 60 minutes of moderate-to-vigorous physical activity (MVPA) per day. Boys had significantly more MVPA than girls (P<0.001). The results revealed that sedentary time had a significant inverse relationship with both gross (r=-0.681, P<0.001) and fine (r=-0.584, P<0.001) motor skills. Moreover, objectively measured physical activity (via accelerometer) showed a direct and significant correlation with gross motor skills (r=0.710, P<0.001), but not with fine motor skills (r=0.064, P=0.307). Sedentary time significantly and inversely impacted both gross (β=-0.68) and fine motor skills (β=-0.58). Furthermore, objective physical activity (measured by accelerometer) had a direct and significant impact on gross motor skills (β=0.71). Conclusions: These findings underscore the necessity to enhance the level of physical activity in children, particularly in girls. We also recommend that physical education teachers and sports coaches incorporate programs in their physical education lessons designed to facilitate motor skills development in children. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We consider the problem of differentiated rate scheduling for the downlink (i.e., multi-antenna broadcast channel), in the sense that the rates required by different users must satisfy certain constraints on their ratios. When full channel state information (CSI) is available at the transmitter and receivers, the problem can be readily solved using dirty paper coding (DPC) and the application of convex optimization techniques on the dual problem which is the multiple access channel (MAC). Since in many practical application full CSI may not be feasible and computational complexity prohibitive when the number of users is large, we focus on other simple schemes that require very little CSI: time-division opportunistic (TO) beamforming where in different time slots (of different lengths) the transmitter performs opportunistic beamforming to the users requiring the same rate, and weighted opportunistic (WO) beamforming where the random beams are assigned to those users having the largest weighted SINR. For single antenna systems we also look at the capacity-achieving superposition coding (SC) scheme. In all cases, we determine explicit schedules to guarantee the rate constraints and show that, in the limit of large number of users, the throughput loss compared to the unconstrained throughput (sum-rate capacity) tends to zero. We further provide bounds on the rate of convergence of the sum-rates of these schemes to the sum-rate capacity. Finally, we provide simulation results of the performance of different scheduling schemes considered in the paper. Index Terms--MIMO, broadcast channel, opportunistic beamforming, QoS, dirty paper coding.

In many problems in wireline networks, it is known that achieving capacity on each link or subnetwork is optimal for the entire network operation. In this paper, we present examples of wireless networks in which decoding and achieving capacity on certain links or subnetworks gives us lower rates than other simple schemes, like forwarding. This implies that the separation of channel and network coding that holds for many classes of wireline networks does not, in general, hold for wireless networks. Next, we consider Gaussian and erasure wireless networks where nodes are permitted only two possible operations: nodes can either decode what they receive (and then re-encode and transmit the message) or simply forward it. We present a simple greedy algorithm that returns the optimal scheme from the exponential-sized set of possible schemes. This algorithm will go over each node at most once to determine its operation, and hence, is very efficient. We also present a decentralized algorithm whose performance can approach the optimum arbitrarily closely in an iterative fashion. Index Terms--Forward/decode scheme, separation principle, wireless networks.

We consider the power efficiency of a communications channel, i.e., the maximum bit rate that can be achieved per unit power (energy rate). For additive white Gaussian noise (AWGN) channels, it is well known that power efficiency is attained in the low signal-to-noise ratio (SNR) regime where capacity is proportional to the transmit power. In this paper, we first show that for a random sensory wireless network with n users (nodes) placed in a domain of fixed area, with probability converging to one as n grows, the power efficiency scales at least by a factor of ([square root of (n)]. In other words, each user in a wireless channel with n nodes can support the same communication rate as a single-user system, but by expending only 1/[square root of (n)] times the energy. Then we look at a random ad hoc network with n relay nodes and r simultaneous transmitter/receiver pairs located in a domain of fixed area. We show that as long as r [less than or equal to] ([square root of n]), we can achieve a power efficiency that scales by a factor of ([square root of (n)]. We also give a description of how to achieve these gains. Index Terms--Capacity, sensor networks, wireless communication systems and networks.

In this paper, a special class of wireless networks, called wireless erasure networks, is considered. In these networks, each node is connected to a set of nodes by possibly correlated erasure channels. The network model incorporates the broadcast nature of the wireless environment by requiring each node to send the same signal on all outgoing channels. However, we assume there is no interference in reception. Such models are therefore appropriate for wireless networks where all information transmission is packetized and where some mechanism for interference avoidance is already built in. This paper looks at multicast problems over these networks. The capacity under the assumption that erasure locations on all the links of the network are provided to the destinations is obtained. It turns out that the capacity region has a nice max-flow min-cut interpretation. The definition of cut-capacity in these networks incorporates the broadcast property of the wireless medium. It is further shown that linear coding at nodes in the network suffices to achieve the capacity region. Finally, the performance of different coding schemes in these networks when no side information is available to the destinations is analyzed. Index Terms--Wireless erasure networks, multicast problems.

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<0.001). Girls had significantly higher use of smartphones in both "before" (P=0.003) and "during" (P<0.001) the pandemic compared with boys. However, no other gender differences were found among male and female adolescents (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. [ABSTRACT FROM AUTHOR]

Using self-reported questionnaires, several studies found that social isolation during the COVID-19 pandemic has significantly changed the level of physical activity (PA) in children and adolescents. Since the objectivity of self-reported PA is limited in several ways, we used modern accelerometers in this study to assess the PA levels of male and female adolescents during the pandemic-related lockdown. Moreover, the association of PA with mental health of the adolescents were analyzed. A total of 136 students (76 girls, mean age of 16.28 ± 0.97 years) from various schools in Iran wore the accelerometer (ActiGraph GT3X-BT) for seven consecutive days. Mental health was measured through the Depression, Anxiety, Stress Scale-21 of Lovibond and Lovibond (1995). Descriptive statistics and independent t-tests were used to analyze the PA levels of male and female students, and linear regressions were computed to examine whether PA predicts mental health status. On average, the daily time spent in moderate-to-vigorous PA (MVPA) was 18.47 min, which is clearly below the WHO guideline of at least 60 min of MVPA per day. Only 4% of adolescents showed MVPA for more than 30 min per day. Male students were significantly more active than their female peers (p = 0.015). As expected, MVPA was negatively associated with mental health issues such as depression, anxiety, and stress. However, the majority of adolescents reported symptoms of mild-to-moderate mental health disorders. These results emphasize the need for targeted strategies and offerings geared to young people’s needs and preferences to promote an adequate level of PA and good mental health during and after the ongoing pandemic. [ABSTRACT FROM AUTHOR]

Introduction. The rapid growth of aging population, in recent years is the result of a process known as the demographic transition. Cognitive disorders such as dementia and delirium, common problems in older adults, are influenced by deteriorating quality and quantity of sleep and psychological well-being and depression. Aim of Study. The purpose of the present research was to investigate the effectiveness of low, medium and highintensity walking in the quality of sleep and psychological wellbeing of elderly women suffering from cognitive impairment. Material and Methods. A pre-test and post-test quasiexperimental research design was selected for the study. The sample consisted of 80 elderly women in the age range of 60-75 years who were randomized into four experimental groups. Exercise intensity was evaluated and controlled by pedometers. In the pre-test and post-test stages, all subjects completed the Pittsburg Sleep Quality Index and the psychological wellbeing scale. The data analysis was conducted using inferential statistical tests such as repeated measures ANOVA and Bonferroni post-hoc tests. Results. In the pre-test stage (prior to the intervention), the results showed no significant differences between the control and experimental groups in terms of wellbeing, sleep quality and their subcomponents (P > 0.05). In the post-test stage (after the intervention), the results indicated significant differences between control and experimental groups in terms of well-being and sleep quality (P < 0.05). The Bonferroni post-hoc test showed that low, moderate, and high-intensity group had higher scores in sleep quality and well-being compared to the control group (P < 0.05). Conclusions. The results showed that low, moderate, and high-intensity walking has a positive and significant effect on well-being and sleep quality of women with cognitive impairments. Thus, based on these findings, walking is recommended as a useful and health promoting method to improve sleep quality and the well-being of women with cognitive impairments. [ABSTRACT FROM AUTHOR]

Background: Absolute and relative information may have different roles during motor learning through observation. Objective: This study aimed to address the effect of observing different information on the learning of the basketball jump shot. Methods: For this purpose, 30 participants were included in the study and divided into three groups (Full Body, Arm, and Wrist) according to the information they observed. Full Body group observed information relating to all body parts, Arm group observed information relating to the throwing arm, and the Wrist group observed the information relating to the throwing wrist. All information was presented in the point light format. During data acquisition, participants performed 30 trials which were observed in the model 5 times before the first trial and once before the remaining trials. Twenty-four hours later, 10 trials were performed as a retention test. After retention, there was a re-acquisition period in which all groups observed full-body information in an order similar to the acquisition period and then performed 10 trials. Accuracy, visual search (eye fixations), and kinematics data (intra-limb coordination variability) were acquired. Results: No between-group difference existed in the accuracy measurement. Results of the kinematics data (intra-limb coordination) showed that Full Body and Arm groups performed more like the model than Wrist group. Visual search data showed that all groups were fixed more on the throwing arm than other parts of the body. Conclusions: These results showed that restricted relative information can be more useful for learning a throwing action. [ABSTRACT FROM AUTHOR]

In this study, we aimed to determine the difference of motor reaction time and accuracy between the patients with moderate multiple sclerosis (MS) and healthy subjects and to determine whether a specified cognitive-motor training can improve the speed and accuracy of information processing in patients with MS. A total of 205 patients (30% males) and 276 age-/gender-matched healthy subjects (31% males) were included in the study. Furthermore, using a stratified randomization method, patients with MS were randomly assigned to one of two groups: active information processing training (AIPT) (n = 49) or post-control (n = 55). The AIPT group was asked to complete a computerized visual-manual training program and the post-control group asked to complete the same task without an increase in difficulty. Before and after the intervention phase, the simple, choice, and semantic reaction times and accuracies of all participants were evaluated using the VLS measurement battery. Our results demonstrated that the case and control group were significantly different in terms of the simple, choice, and semantic motor reaction times and accuracies. Compared with the pre-intervention phase, the AIPT and control group's performances in the post-intervention phase were considerably improved in simple, choice, and semantic motor reaction times and choice and semantic motor reaction accuracies. The results also showed that the AIPT group performed significantly better than the post-control group in terms of simple and choice motor reaction times. We showed the positive effects of training on the performance of patients with MS in motor reaction time and accuracy. [ABSTRACT FROM AUTHOR]

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disorder which is associated with accumulation of fats in the liver. It causes a wide variety of pathological effects such as non-alcoholic steatohepatitis (NASH) and cirrhosis, insulin resistance, obesity, hypertension, dyslipidaemia, diabetes and cardiovascular disease. The molecular mechanisms that cause the initiation and progression of NAFLD are not fully understood. Oxidative stress (OS) induced by reactive oxygen species (ROS) and inflammation are likely a significant mechanism which can lead to hepatic cell death and tissue injury. Mitochondrial abnormalities, down-regulation of several antioxidant enzymes, glutathione (GSH) depletion and decreased activity of GSH-dependent antioxidants, accumulation of leukocytes and hepatic inflammation are the major sources of ROS overproduction in NAFLD. Excessive production of ROS suppresses the capacity of other antioxidant defence systems in NAFLD and causes further oxidative damage. Regular exercise can be considered as an effective strategy for treatment of NAFLD. It improves NAFLD by reducing intrahepatic fat content, increasing β-oxidation of fatty acids, inducing hepato-protective autophagy, overexpressing peroxisome proliferator-activated receptor- γ (PPAR-γ), as well as attenuating hepatocyte apoptosis and increasing insulin sensitivity. Exercise training also suppresses ROS overproduction and OS in NAFLD via up-regulation of several antioxidant enzymes and anti-inflammatory mediators. Therefore, an understanding of these molecules and signalling pathways gives us valuable information about NAFLD progression and a method for developing a suitable clinical treatment. This review aimed to evaluate sources of ROS and OS in NAFLD and the molecular mechanisms involved in the beneficial effects of exercises on NAFLD. [ABSTRACT FROM AUTHOR]