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Faigenbaum, AD, Kraemer, WJ, Blimkie, CJR, Jeffreys, I, Micheli, LJ, Nitka, M, and Rowland, TW. Youth resistance training: Updated position statement paper from the National Strength and Conditioning Association. J Strength Cond Res 23(5): S60-S79, 2009-Current recommendations suggest that school-aged youth should participate daily in 60 minutes or more of moderate to vigorous physical activity that is developmentally appropriate and enjoyable and involves a variety of activities (). Not only is regular physical activity essential for normal growth and development, but also a physically active lifestyle during the pediatric years may help to reduce the risk of developing some chronic diseases later in life (). In addition to aerobic activities such as swimming and bicycling, research increasingly indicates that resistance training can offer unique benefits for children and adolescents when appropriately prescribed and supervised (). The qualified acceptance of youth resistance training by medical, fitness, and sport organizations is becoming universal ().Nowadays, comprehensive school-based programs are specifically designed to enhance health-related components of physical fitness, which include muscular strength (). In addition, the health club and sport conditioning industry is getting more involved in the youth fitness market. In the U.S.A., the number of health club members between the ages of 6 and 17 years continues to increase () and a growing number of private sport conditioning centers now cater to young athletes. Thus, as more children and adolescents resistance train in schools, health clubs, and sport training centers, it is imperative to determine safe, effective, and enjoyable practices by which resistance training can improve the health, fitness, and sports performance of younger populations.The National Strength and Conditioning Association (NSCA) recognizes and supports the premise that many of the benefits associated with adult resistance training programs are attainable by children and adolescents who follow age-specific resistance training guidelines. The NSCA published the first position statement paper on youth resistance training in 1985 () and revised this statement in 1996 (). The purpose of the present report is to update and clarify the 1996 recommendations on 4 major areas of importance. These topics include (a) the potential risks and concerns associated with youth resistance training, (b) the potential health and fitness benefits of youth resistance training, (c) the types and amount of resistance training needed by healthy children and adolescents, and (d) program design considerations for optimizing long-term training adaptations. The NSCA based this position statement paper on a comprehensive analysis of the pertinent scientific evidence regarding the anatomical, physiological, and psychosocial effects of youth resistance training. An expert panel of exercise scientists, physicians, and health/physical education teachers with clinical, practical, and research expertise regarding issues related to pediatric exercise science, sports medicine, and resistance training contributed to this statement. The NSCA Research Committee reviewed this report before the formal endorsement by the NSCA.For the purpose of this article, the term children refers to boys and girls who have not yet developed secondary sex characteristics (approximately up to the age of 11 years in girls and 13 years in boys; Tanner stages 1 and 2 of sexual maturation). This period of development is referred to as preadolescence. The term adolescence refers to a period between childhood and adulthood and includes girls aged 12-18 years and boys aged 14-18 years (Tanner stages 3 and 4 of sexual maturation). The terms youth and young athletes are broadly defined in this report to include both children and adolescents.By definition, the term resistance training refers to a specialized method of conditioning, which involves the progressive use of a wide range of resistive loads and a variety of training modalities designed to enhance health, fitness, and sports performance. Although the term resistance training, strength training, and weight training are sometimes used synonymously, the term resistance training encompasses a broader range of training modalities and a wider variety of training goals. The term weightlifting refers to a competitive sport that involves the performance of the snatch and clean and jerk lifts.This article builds on previous recommendations from the NSCA and should serve as the prevailing statement regarding youth resistance training. It is the current position of the NSCA that:

Many position stands and review papers have refuted the myths associated with resistance training (RT) in children and adolescents. With proper training methods, RT for children and adolescents can be relatively safe and improve overall health. The objective of this position paper and review is to highlight research and provide recommendations in aspects of RT that have not been extensively reported in the pediatric literature. In addition to the well-documented increases in muscular strength and endurance, RT has been used to improve function in pediatric patients with cystic fibrosis and cerebral palsy, as well as pediatric burn victims. Increases in children's muscular strength have been attributed primarily to neurological adaptations due to the disproportionately higher increase in muscle strength than in muscle size. Although most studies using anthropometric measures have not shown significant muscle hypertrophy in children, more sensitive measures such as magnetic resonance imaging and ultrasound have suggested hypertrophy may occur. There is no minimum age for RT for children. However, the training and instruction must be appropriate for children and adolescents, involving a proper warm-up, cool-down, and appropriate choice of exercises. It is recommended that low- to moderate-intensity resistance exercise should be done 2-3 times/week on non-consecutive days, with 1-2 sets initially, progressing to 4 sets of 8-15 repetitions for 8-12 exercises. These exercises can include more advanced movements such as Olympic-style lifting, plyometrics, and balance training, which can enhance strength, power, co-ordination, and balance. However, specific guidelines for these more advanced techniques need to be established for youth. In conclusion, an RT program that is within a child's or adolescent's capacity and involves gradual progression under qualified instruction and supervision with appropriately sized equipment can involve more advanced or intense RT exercises, which can lead to functional (i.e., muscular strength, endurance, power, balance, and co-ordination) and health benefits.

Abstract: Morris, SJ, Oliver, JL, Pedley, JS, Radnor, JM, Haff, GG, Cooper, S-M, and Lloyd, RS. Kinetic predictors of weightlifting performance in young weightlifters. J Strength Cond Res 38(9): 1551-1560, 2024-Relationships between force-generating capabilities and weightlifting performance ( e.g ., snatch, clean and jerk [C&J], and combined total) have previously been explored in adult weightlifters; however, associations in young athletes are unknown. The purpose of this study was twofold: (a) to examine the relationships between countermovement jump (CMJ) and isometric midthigh pull (IMTP) kinetics and weightlifting performance in young weightlifters and (b) to determine the proportion of weightlifting performance that could be accounted for by CMJ and IMTP kinetics using principal component analysis (PCA). Thirty-seven young weightlifters (12-18 years of age) completed 3 trials of CMJ and 2 trials of the IMTP assessments on dual force plates. Recent competition maximum loads, obtained within 2 weeks of the data collection, for the C&J and snatch were also recorded. Pearson's zero-order correlation coefficients demonstrated moderate to very high correlations ( r = 0.359-0.801; all p ≤ Benjamini-Hochberg critical values [ B-Hα ]) between CMJ kinetic variables, including jump height, average braking force, average braking velocity, absolute and relative braking net impulse, absolute and relative force at minimum displacement, absolute and relative propulsive force, absolute and relative propulsive net impulse and average propulsive velocity, and weightlifting performance. High to very high correlations were evident between IMTP peak force and relative peak force and all weightlifting performance metrics (snatch, C&J, combined total, combined total [kg]/body mass [kg -0.67 ], and Sinclair's total; r = 0.538-0.796; p ≤ B-Hα ). Components from the PCA were used to conduct stepwise, multiple, linear regression analyses. Moderate (45.8-52.9%) and large percentages (79.1-81.3%) of variance in absolute measures of weightlifting performance were explained by IMTP peak force variables and CMJ propulsive variables, respectively. These novel findings indicate that IMTP peak force variables and CMJ propulsive variables could provide valuable insight for talent identification and long-term athletic development in junior weightlifting pathways., (Copyright © 2024 National Strength and Conditioning Association.)

BACKGROUND: External focus isometric exercises using a paper balloon can change trunk muscle activation in the chest squeeze; however, it is unknown whether this method affects muscle activities in conventional exercises. OBJECTIVE: To check variations of trunk muscle activity during front plank (static task) and shoulder press (dynamic task) both with and without instruction to avoid crushing an object. METHODS: Twenty-six healthy adult males aged 19–49 were recruited. Ten trunk muscle activities were measured using surface electromyography during a front plank and dynamic shoulder press exercises, both with and without external-focus instruction. RESULTS: Adding the external-focus using the paper balloon to the front plank significantly activated 8 out of the 10 muscles. In the downward shoulder press, 5 out of 10 muscles with 50% 1 RM, 2 out of 10 muscles with 100% 1 RM were significantly activated. CONCLUSIONS: Adding external-focus instruction using paper balloon increases trunk muscles in front plank and shoulder press while possibly improving trunk stability. Novel exercises using paper balloon may efficiently activate specific muscles without external loading thus possibly reducing the stress on the involved joints during exercise. [ABSTRACT FROM AUTHOR]

The transportation industry involves various ergonomic injuries caused by activities exceeding workers' capabilities. Although the construction industry has been thoroughly studied regarding work--related injuries, hazardous activities, and effective ergonomic solutions, there is a lack of such research in the transportation sector. However, injuries, risky activities, and effectiveness of solutions may be different in transportation activities due to different work duration, intensity, and frequency. Thus, this research intends to explore the common work-related injuries, hazardous transportation activities, and the effectiveness of ergonomic solutions for transportation maintenance workers. This thorough examination incorporated historical injury records, online surveys, in-person site observations, and field experiments. Specifically, a preliminary list was first created based on transportation workers' historical injury data, including common injured worker positions, injury types, activities causing most injures, and potential risk factors. An online survey was then designed to identify work-related injuries and activities. Following observations, field experiments involved 29 transportation maintenance workers. Back injuries emerged as the most prevalent when engaging in lifting and pushing/pulling tasks. Using a back exoskeleton can eliminate physical fatigue risks when lifting weights of 50 pounds or more. In addition, lifting lighter loads (31.5 pounds) can significantly reduce the risk of injuries. RELEVANCE TO HUMAN FACTORS/ERGONOMICS THEORY: Prevalent work-related injuries, hazardous activities, and effective ergonomic solutions have been thoroughly researched in the construction domain. However, with the injury and fatality statistics of the transportation industry, there is a lack of studies investigating what injuries are prevalent, what activities are risky, and what solutions could be effective in the transportation industry. To the best of author's knowledge, this paper is the first research presenting a new framework exploring prevalent work-related injuries, hazardous activities, and ergonomic solutions' effectiveness in the domain of transportation maintenance work through the analysis of historical data, online survey data, onsite observations, and field experiment. Theoretically, this paper fills the lack of research about identification of ergonomic injuries and risky activities in the transportation industry, and contributes to the development of ergonomically effective process, practice, and technique for improved health and safety in the transportation maintenance work. Practically, the research team worked with a state Department of Transportation to help the transportation-related workers, managers, and organizations better realize the risky activities and understand how to prevent the risks. [ABSTRACT FROM AUTHOR]

This paper presents a lifting‐line implementation in the framework of a Lagrangian vortex particle method (LL‐VP). The novelty of the present implementation lies in the fluid particles properties definition and in the particles shedding process. In spite of mimicking a panel method, the LL‐VP needs some peculiar treatments described in the paper. The present implementation converges rapidly and efficiently during the shedding sub‐iteration process. This LL‐VP method shows good accuracy, even with moderate numbers of sections. Compared to its panel or vortex filaments counterparts, more frequently encountered in the literature, the present implementation inherently accounts for the diffusion term of the Navier‐Stokes equations, possibly with a turbulent viscosity model. Additionally, the present implementation can also account for more complex onset flows: upstream ambient turbulence and upstream turbine wakes. After validation on an analytical elliptic wing configuration, the model is tested on the Mexnext‐III wind turbine application, for three reduced velocities. Accurate results are obtained both on the analytical elliptic wing and on the New MEXICO rotor cases in comparison with other similar numerical models. A focus is made on the Mexnext‐III wake analysis. The numerical wake obtained with the present LL‐VP is close to other numerical and experimental results. Finally, a last configuration with three tidal turbines in interaction is considered based on an experimental campaign carried out at the IFREMER wave and current flume tank. Enhanced turbine‐wake interactions are highlighted, with favourable comparisons with the experiment. Hence, such turbine interactions in a farm are accessible with this LL‐VP implementation, be it wind or tidal energy field. [ABSTRACT FROM AUTHOR]

With the development of steel-structure construction technology in high-rise buildings, the design and construction of high-rise steel structures tend to be complicated. Based on the Zhuhai Tiejian Square project, the fluid-structure coupling calculation analysis and on-site monitoring are carried out in view of the wind load of the high-altitude steel-structure connecting bridge in the hoisting stage of the Zhuhai Tiejian Square project. The main structure of the project is four towers and five high-altitude, small-spacing steel structures connecting the four towers. The lifting process of the third zone is taken as the analysis object, and the hoisting idea of "low-altitude hoisting, overall lifting" is adopted. Because the span of the high-altitude steel-structure connecting bridge is small and the installation height is high, the influence of wind load on the hoisting process cannot be ignored. Therefore, the unidirectional fluid-structure coupling model of the high-altitude small-space steel-structure connecting bridge in the third zone was established by using CFD calculation software ANSYS Fluent 2022 R1, and the corresponding flow field and solid calculation results were obtained and analyzed. The analysis results show that the lifting structure still produces a certain deformation when the wind speed is 5 m/s or 10 m/s, and the calculation results show that the stress calculation results are still within the safe range of steel strength for the sensitivity of the lifting structure under wind load. With the increase of wind speed, the local maximum stress of the structure increases greatly, but the overall deformation remains stable, which indicates that the greatest challenge of hoisting steel structures under wind load may be the stability direction rather than the strength, so it is necessary to strictly monitor the displacement deformation of the structure during construction. Then, through the monitoring of the overall lifting process of the high-altitude, large-span, steel-connected structure of Zhuhai Tiejian Square from pre-lifting to formal lifting, real-time monitoring and data analysis show that the lifting process of the high-altitude steel bridge of Zhuhai Tiejian Square is safe and reliable, the force transformation of each component is reasonable, the lifting process is relatively stable, the external environment has little impact, and the expected monitoring effect has been achieved. The calculation simulation and on-site monitoring in this paper can provide theoretical and practical guidance for the construction safety under the influence of wind load in the construction process of high-altitude steel-structure hoisting, and provide an important reference value for similar projects. [ABSTRACT FROM AUTHOR]

Background: Isotonic exercise is the most common mode of strength training. Isotonic strength is often measured in the movement that was exercised, but isometric and isokinetic movements are also commonly used to quantify changes in muscular strength. Previous research suggests that increasing strength in one movement may not lead to an increase in strength in a different movement. Quantifying the increase in strength in a movement not trained may be important for understanding strength training adaptations and making recommendations for resistance exercise and rehabilitation programs. Objective: To quantify changes in non-specific strength relative to a control. Design: A systematic review and random effects meta-analysis was conducted investigating the effects of isotonic strength training on isotonic and isokinetic/isometric strength. Search and Inclusion: This systematic review was conducted in Google scholar, PubMed, Academic Search Premier, and MENDELEY. To be included in this review paper the article needed to meet the following criteria: (1) report sufficient data for our variables of interest (i.e., changes in isotonic strength and changes in isokinetic or isometric strength); (2) include a time-matched non-exercise control; (3) be written in English; (4) include healthy human participants over the age of 18 years; (5) the participants had to train and test isotonically; (6) the participants had to be tested isokinetically or isometrically on a device different from that they trained on; (7) the non-specific strength task had to test a muscle involved in the training (i.e., could not have trained chest press and test handgrip strength); and (8) the control group and the experimental group had to perform the same number of strength tests. Results: We completed two separate searches. In the original search a total of 880 papers were screened and nine papers met the inclusion criteria. In the secondary search a total of 2594 papers were screened and three additional papers were added (total of 12 studies). The overall effect of resistance training on changes in strength within a movement that was not directly trained was 0.8 (Cohen's d) with a standard error of 0.286. This overall effect was significant (t = 2.821, p = 0.01) and the 95% confidence interval (CI) is 0.22–1.4. The overall effect of resistance training on strength changes within a movement that was directly trained was 1.84 (Cohen's d) with a standard error of 0.296. This overall effect was significant (t = 6.221, p < 0.001) and the 95% CI is 1.23–2.4. Conclusion: The results of our meta-analysis suggest that strength increases in both the specific and non-specific strength tests. However, the smaller effect size associated with non-specific strength suggests that it will be difficult for a single study to meaningfully investigate the transfer of strength training adaptions. [ABSTRACT FROM AUTHOR]

Understanding the importance of movement asymmetries and variations in technique proficiency across different level of weightlifters is crucial. The purpose of this study was to examine differences in joint kinematics, muscle activation, and barbell parameters between elite and varsity weightlifters during the snatch utilizing integrated 3D motion capture and EMG systems. In addition, it analyzes symmetries in joint kinematics and muscle activation in both groups. Ten female participants, comprising 5 elite and 5 varsity weightlifters, along with thirteen male participants, consisting of 6 elite and 7 varsity weightlifters during snatch were measured. Several asymmetries in posture and muscle activation were identified in both elite and varsity weightlifters. In addition, elite weightlifters exhibited significantly more flexed knees than varsity counterparts (p < 0.05) at the conclusion of the second pull and at the highest position of the barbell. Furthermore, significantly lower activity in gluteus maximus was detected in elite weightlifter at the highest point of the barbell than in the varsity groups (p < 0.05). Moreover, elite males achieved a lower maximum height for the barbell compared to varsity males (p = 0.006). Furthermore, elite females demonstrated less horizontal displacement (D2x) (p = 0.005) than varsity counterparts. Varsity women presented significantly lower horizontal velocity (p = 0.003) at the conclusion of the second pull than varsity counterparts. Despite several asymmetries detected, those may not be critical factors in achieving a successful snatch lift, given that all weightlifters successfully completed the lift. However, variations in posture and muscle activation may still be associated with improvements in technique proficiency across different levels of weightlifters., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: CrossFit® combines different types of activities (weightlifting, gymnastics, and cardiovascular training) that challenge aerobic and anaerobic pathways. Over the last few years, the scientific interest in CrossFit® has increased considerably. However, there have been no published reviews characterizing the physical demands and physiological responses to CrossFit®. The present study synthesizes current evidence on the physical demands and physiological responses to CrossFit®. Methods: The search was performed in three electronic databases (PubMed, Scopus, and Web of Science). Manuscripts related to the physical and physiological performance of adult CrossFit® participants written in English, Portuguese, and Spanish were retrieved for the analysis. Results: In addition, a meta-correlation was conducted to examine the predictors of CrossFit® performance. A total of 68 papers were included in the review. Physical and physiological markers differed between the different workouts analyzed. In addition, 48 to 72 h are needed to recover from a CrossFit® challenge. Specific tests that involve CrossFit® movements were more related to CrossFit® performance than non-specific. Conclusion: Although the characterization of CrossFit® is dependent on the workout examined, the benefits of muscle hypertrophy are aligned with the recent findings of concurrent training. The characterization of CrossFit® entire sessions and appropriate recovery strategies should be considered in future studies to help coaches manipulate and adjust the training load. [ABSTRACT FROM AUTHOR]

This research explains how unexpected and uncontrollable chance events can facilitate or constrain competitive advantage in sport, through a study of Iran in five weight division-specific sports (i.e. weightlifting, wrestling, taekwondo, judo and boxing). The analysis relied on data collected from 25 semi-structured interviews. The study identifies six types of chance events impacting elite sport – economic crises, sport-specific crises, diplomatic tensions with foreign countries, political decisions by foreign governments, technological discontinuities, and new policies and rules of international governing bodies. The contributions of this paper to the literature reside in the identification of crises as a major type of chance events and the discovery of some chance events specific to elite sport. [ABSTRACT FROM AUTHOR]

Despite the lifting of COVID‐19 restrictions eventually, the destabilising consequences of the pandemic on migration persist and continue to worsen. Based on in‐depth interviews with 25 Chinese international students, this paper asks what new forms of education transnationality are being introduced by the intersection of digital mobility and physical immobility. Using Henri Lefebvre's (2004) rhythmanalysis, we understand stay‐at‐home international students' sensual and physical experiences as palpable aspects of daily existence that not only constitute transnational lived temporalities but also trigger 'small accidents', leading to potentially larger‐scale temporal changes. By attending to the dynamic interaction between their agency and the external structure, we conclude that situated corporeal and emotional suffering, embodied transitioning strategies, and changes to mobility pathways make up the fabric of the immobile everydayness of the new 'grafted transnationalism'. This paper contributes to the existing scholarship on transnational education by highlighting the dual sense of exclusion that students experience in both corporeal and social time, as well as the multilayered possibilities of reorientation as their way of regaining control of dyssynchronous rhythmic encounters. It also sorts out the implications of lifetime geography on students' differentially distributed vulnerability and susceptibility when facing life course disruptions. [ABSTRACT FROM AUTHOR]

For modern sport training, critical posture recognition of athletes can be helpful for athlete training. This paper proposes convolutional neural networks using a two-stage evaluation mechanism to recognize four critical postures of a weightlifter, that is, force releasing, knee flexion, knee extension and highest point. Using the proposed convolutional neural networks classify images and extract image features. Meanwhile, a two-stage evaluation mechanism is adopted to calculate the scores of image features, based on the calculated scores, the four critical postures can be accurately recognized. Experimental results show that the accuracy of our method is 92.85% in the recognition of the four critical postures, which defeats the competitive methods in critical posture recognition. Moreover, the training time of the proposed method linearly augments along with the increasing of data volume, that is, non-exponential growth, consequently, our method can be applied to large-scale image datasets. We demonstrate that the two-stage mechanism can calculate the scores of image features independently of specific scenarios, which assist neural networks improve classification capabilities. Moreover, using the two-stage mechanism can simplify the designed complexity of neural network architectures, thus reducing the training parameter of neural networks in the process of critical posture recognition. [ABSTRACT FROM AUTHOR]

Many adolescents lack the requisite physical preparation for sport participation and PA. Multi-sport participation and resistance training during youth (age 5-11) and adolescence (age 12-17) years can positively effect physical activity levels, health outcomes, and promote long-term athletic development (LTAD). The National Strength and Conditioning Association (NSCA) created a position statement regarding LTAD. K-12 schools provide an ideal environment to deliver LTAD programs. Limited literature exists regarding how best to implement LTAD within K-12 physical education. The purpose of this paper is to provide physical educators with strategies to implement LTAD within K-12 programming. In this paper, we have described how specific curriculum models are aligned with LTAD and can support developmentally appropriate progression of PE content across instructional levels. Implementation of LTAD programs within PE utilize standards based curriculum design to create multi-curricular offerings that include resistance training. [ABSTRACT FROM AUTHOR]

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In this third paper in a series of four, the focus is to investigate the modern UK economy, considering a wider scope than economic growth and national performance. Since the beginnings of sustained economic growth, standard of living has increased dramatically in the UK and life expectancy and health outcomes have improved. Economic growth has proven itself throughout history, and globally, as a transformative force to lift people out of poverty and improve standard of living. However, significant inequalities, which are contributing to negative health, social and economic outcomes for groups of the population, persist. A growing nation has become a divided nation. [ABSTRACT FROM AUTHOR]

Abastrct: The waverider is deemed the most promising configuration for hypersonic vehicle with its high lift-to-drag ratio at design conditions. However, considering the serious aero-heating protection, the sharp leading edge must be blunted. The existing traditional bluntness methods including the following two types: "reducing material method" and "adding material method". Compared to the initial waverider, the volume will be smaller or larger using the traditional methods. With the fixed blunted radius, the volume and aerodynamic performance is determined. In this paper, a new bluntness method which is named "mixing material method" is developed. In this new method, a new parameter is introduced based on the traditional two bluntness methods. Under fixed blunted radius, the volume and aerodynamic performance can be changed within a wide range by adjusting the parameter. When the parameter is 0 and 1, the novel blunted method degenerated into the "reducing material method" and "adding material method" respectively. The influence of new parameter on the aerodynamic characteristics and volume are studied by numerical simulation. Results show that the volume, lift and lift-to-drag ratio increases with the increase of the parameter under the fixed blunt radius, but simultaneously, the drag will also increase. Therefore, considering the different requirements of the air-breathing hypersonic aircrafts for the balance of thrust and drag, lift and weight, a suitable bluntness parameter can be selected to achieve a balance. This research can provide reference for hypersonic waverider vehicle design. [ABSTRACT FROM AUTHOR]

Financial sanctions have become a major component of American foreign policy. Since 2015, the number of blacklisted actors has nearly tripled, coinciding with US financial campaigns against Iran, North Korea, and Russia. This paper centers an under-examined paradox of this proliferation: the complexity of lifting financial sanctions. Indeed, successful sanctions regimes necessitate both sticks (punitive sanctions) and carrots (economic incentives). Yet financial sanctions often limit the economic benefits promised to target states, as banks and other financial institutions risk hefty material and reputational costs if they are to cooperate with previously sanctioned actors. Thus, while financial sanctions are effective at producing negative market reactions against a target, they can be hugely damaging if market actors do not cooperate with the lifting of sanctions. To capture this dynamic, this paper leverages process-tracing to observe financial market reactions to sanctions relief in three key cases—Iran (2010–2015), North Korea (2002–2007), and Libya (1996–2008). It finds that in each case, the presence or absence of US Treasury blacklisting corresponds to the post-sanction willingness of financial actors to extend sanctions relief to targeted states. In doing so, this study identifies "reputational risk" as the primary causal mechanism limiting a target's reintegration into the global economy. [ABSTRACT FROM AUTHOR]

Optimisation-based predictive models are widely-used to explore the lifting strategies. Existing models incorporated empirical subject-specific posture constraints to improve the prediction accuracy. However, over-reliance on these constraints limits the application of predictive models. This paper proposed a multi-phase optimisation method (MPOM) for two-dimensional sagittally symmetric semi-squat lifting prediction, which decomposes the complete lifting task into three phases—the initial posture, the final posture, and the dynamic lifting phase. The first two phases are predicted with force- and stability-related strategies, and the last phase is predicted with a smoothing-related objective. Box-lifting motions of different box initial heights were collected for validation. The results show that MPOM has better or similar accuracy than the traditional single-phase optimisation (SPOM) of minimum muscular utilisation ratio, and MPOM reduces the reliance on experimental data. MPOM offers the opportunity to improve accuracy at the expense of efforts to determine appropriate weightings in the posture prediction phases. Practitioner summary: Lifting optimisation models are useful to predict and explore the human motion strategies. Existing models rely on empirical subject-specific posture constraints, which limit their applications. A multi-phase model for lifting motion prediction was constructed. This model could accurately predict 2D lifting motions with less reliance on these constraints. [ABSTRACT FROM AUTHOR]

Manual material handling and load lifting are activities that can cause work-related musculoskeletal disorders. For this reason, the National Institute for Occupational Safety and Health proposed an equation depending on the following parameters: intensity, duration, frequency, and geometric characteristics associated with the load lifting. In this paper, we explore the feasibility of several Machine Learning (ML) algorithms, fed with frequency-domain features extracted from electromyographic (EMG) signals of back muscles, to discriminate biomechanical risk classes defined by the Revised NIOSH Lifting Equation. The EMG signals of the multifidus and erector spinae muscles were acquired by means of a wearable device for surface EMG and then segmented to extract several frequency-domain features relating to the Total Power Spectrum of the EMG signal. These features were fed to several ML algorithms to assess their prediction power. The ML algorithms produced interesting results in the classification task, with the Support Vector Machine algorithm outperforming the others with accuracy and Area under the Receiver Operating Characteristic Curve values of up to 0.985. Moreover, a correlation between muscular fatigue and risky lifting activities was found. These results showed the feasibility of the proposed methodology—based on wearable sensors and artificial intelligence—to predict the biomechanical risk associated with load lifting. A future investigation on an enriched study population and additional lifting scenarios could confirm the potential of the proposed methodology and its applicability in the field of occupational ergonomics. [ABSTRACT FROM AUTHOR]

The primary focus of this article is to highlight that an exponentially weighted model should be used to calculate an athlete's workload and that physiological and biomechanical workloads should be considered as two distinct factors in calculating an athlete's total workload. Current methods used to assess an athlete's workload, such as the Olympic Weightlifting and Training Impulse (TRIMP) methods, use a version of the traditional "Volume x Intensity" equation to calculate workload. This is done by calculating intensity, through either internal (Heart Rate, Rate of Perceived Exertion (RPE), Blood Lactate, etc.) or external (Weight used, Distance Travelled, etc.) metrics, and volume, through either duration or repetitions, depending on the activity at hand. While useful for monitoring athlete workloads, these methods use a linear model to calculate accumulated workload, with two efforts at 50% maximal intensity being considered the same as one effort at 100% of maximal intensity, something which has been shown anecdotally and through research to be untrue. This paper suggests that the workload calculations should be modified from "Volume x Intensity" to "Volume x IntensityX" to account for the fatigue cost of an exercise increasing exponentially as exercise intensity increases. The paper also details how and why this method, or traditional methods, can be modified so that an athletes' total workload is the sum of their physiological and biomechanical workloads, instead of one all-encompassing metric, and how this can better aid coaches to track their athletes and identify overload or underload related risk factors. [ABSTRACT FROM AUTHOR]

A growing body of research supports weight lifting as an effective adjunct intervention in the treatment of psychological trauma and trauma-related disorders. However, studies indicate that numerous barriers exist to participation in weight lifting, especially among populations disproportionately impacted by trauma. Trauma-informed care offers a paradigm for service delivery that aims to empower clients to access healing resources by attending to six domains of experience: safety, trustworthiness and transparency, peer support, collaboration and mutuality, empowerment, voice and choice, and cultural, historical, and gender issues. This mixed-methods study utilizes semi-structured, one-on-one interviews and surveys to inform the design of an evidence-based trauma-informed weight lifting program for trauma survivors. The contributions of this paper are twofold. First, the salient experiential categories for conceptualizing psychological healing in the gym environment are presented, informed by the lived experiences and recommendations of a national sample of trauma-impacted weight lifters. Second, based on the findings of this study, guidelines are proposed for the development of trauma-informed weight lifting programming that may be incorporated into the practice habits of personal trainers. The results of this study aid in the reduction in barriers that currently limit the adoption of weight lifting as an adjunct intervention for trauma and contribute to the professionalization of personal trainers in trauma-related competencies [ABSTRACT FROM AUTHOR]

Load carriage experiments are typically performed from a linear perspective that assumes that movement variability is equivalent to error or noise in the neuromuscular system. A complimentary, nonlinear perspective that treats variability as the object of study has generated important results in movement science outside load carriage settings. To date, no systematic review has yet been conducted to understand how load carriage dynamics change from a nonlinear perspective. The goal of this systematic review is to fill that need. Relevant literature was extracted and reviewed for general trends involving nonlinear perspectives on load carriage. Nonlinear analyses that were used in the reviewed studies included sample, multiscale, and approximate entropy; the Lyapunov exponent; fractal analysis; and relative phase. In general, nonlinear tools successfully distinguish between unloaded and loaded conditions in standing and walking, although not in a consistent manner. The Lyapunov exponent and entropy were the most used nonlinear methods. Two noteworthy findings are that entropy in quiet standing studies tends to decrease, whereas the Lyapunov exponent in walking studies tends to increase, both due to added load. Thus, nonlinear analyses reveal altered load carriage dynamics, demonstrating promise in applying a nonlinear perspective to load carriage while also underscoring the need for more research. [ABSTRACT FROM AUTHOR]

The paper includes partial results of the development project entitled “The first Polish gantry crane with high lifting capacity for the shipbuilding industry adapted to work in difficult wind conditions - development and demonstration” (no POIR.01.02.00-00-0017/18). Due to the requirements of working in challenging wind conditions, the crane will be equipped with the sheave block with a hook operating automatically. To resolve this problem, mathematical and then physical models of the innovative crane are required. Therefore, to obtain reliable models, the measurement of the dynamics of the sheave block of crane with high lifting capacity was carried out. At the beginning of the paper, the conditions and used measurement stand are included. Then, the time and frequency analysis of the received measurement results are described. Moreover, the determination of the crane parameters is also presented. The analysis results will be used in further research to tune both the simulation and the physical models of the crane with an automatic hook, which are being developed. [ABSTRACT FROM AUTHOR]

In the process of designing a marine propeller, hydroelasticity effects are neglected in most cases, due to the negligible influence of the blade's deformation on its hydrodynamic characteristics. However, there are cases where the impact of hydroelasticity is crucial, for example in the case of high skew-back propellers or heavy-loaded composite propellers. Furthermore, the importance of composite propellers is growing due to their wide range of application, for instance in naval ships and unmanned vehicles. Although structural models and two-way fluid-structure interactions are implemented in most commercial CFD solvers, their relevance to the design process is severely limited due to the high computational cost for a single iteration. An effective solution would therefore be to implement a two-way fluid-structure interaction model in the lifting surface software, which is commonly accepted as a design tool due to its relatively low computational time and its applicability to multi-criteria optimisation. This paper presents the results of hydrodynamic analyses of an elastic propeller carried out using in-house software based on the lifting surface flow model, and extended with the FEM model for the blade structure. The results are compared with experimental measurements and computational analyses with the commercial RANS solver STAR-CCM+. [ABSTRACT FROM AUTHOR]

In view of the deficiency that the traditional importance ranking method cannot be used to objectively and comprehensively evaluate the importance of the causes of hoisting injuries, an importance ranking method based on topological potential is proposed by using complex network theory and field theory in physics. First, the causes of 385 reported lifting injuries are divided into 36 independent causes at four levels through a systematic analysis approach, and the relationships among these causes are obtained through the Delphi method. Then, the accident causes are treated as nodes, and the relationships among the causes are used as edges to establish a network model of the causes of lifting accidents. The out-degree and in-degree topological potential of each node are calculated, and an importance ranking of lifting injuries causes is obtained. Finally, based on 11 evaluation indexes commonly used to assess node importance (node degree, betweenness centrality, etc.), the ability of the method proposed in this paper to effectively identify the key nodes in the cause network of lifting accidents is verified, and the conclusions can guide the safe implementation of lifting operations. [ABSTRACT FROM AUTHOR]

Composite indicators have proved to be a suitable tool for the evaluation of complex phenomena, by enabling a large amount of information to be concentrated in a unique value. In this paper, a methodology based on geometric aggregation and free-selection of weights is proposed for the evaluation of the educational systems of OECD countries. In an effort to carry out a global evaluation, not only is a group of indicators considered to measure the academic outcomes, but also a group of indicators that measure the social dimension of the educational system and the self-perceptions of the students regarding their academic stage. The features of the proposed methodology enable the results for male and female students to be compared separately, since not only identify the contribution of each aspect to the global indicator, but also ascertain the sources of the differences between the values obtained for the male and female subgroups. [ABSTRACT FROM AUTHOR]

Copyright of Fonseca: Journal of Communication is the property of Revista Fonseca Journal of Communication and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The oil and gas production rate normally declines due to several parameters, so the artificial lift technique is effective and requires energy to lift the fluid column in the wellbore and optimize production. There are various techniques used recently but the two techniques applicable in the oil and gas industry are gas lift and electrical submersible pumping. Gas lift technique aims to lower flowing bottomhole pressure and decrease the density of the well fluid in the tubing by injecting high-pressure gas from the annulus. Thus, producing a pressure differential that allows flowing the fluid from the wellbore to the surface. On the other hand, ESP lifts the fluid in the wellbore by exposing it to centrifugal force and rotation in each pump stage that changes kinetic energy to potential energy. The design for ESP and gas lift were performed using Prosper software to enhance the production. Prosper is an artificial lift software simulator that troubleshoots, designs and evaluates lifting mechanisms for field optimization and digital oil field system. The analysis of ESP and Gas lift were conducted to choose a suitable method for the determined field. Typical gas injection rates are computed to ensure extreme oil production and sensitivity analysis of water cuts is directed which yields the greatest water cut for upgrading the total oil production. Field data were obtained from existing two wells horizontal and vertical that stopped due to reduction in reservoir pressure, thus required to apply artificial lift methods to lift wellbore fluids to surface and production facilities. The analyzed results showed that, after comparing the maximum oil production rate for both horizontal and vertical wells, the ESP system provided an increase in oil production compared to the gas lift method in this field. Both wells are increasing significantly in terms of production when using ESP systems. Both wells have a total liquid rate, which lies well within the production range of the pump between the minimum and the best efficiency line curve. [ABSTRACT FROM AUTHOR]

In industries, difficult work is being decreased everywhere scale to expand effectiveness and exactness, and gain benefit by introducing robots that can do repetitive works at lesser expense of preparing. A onetime establishment of such a gadget may cost an enormous sum at first, yet in the more drawn out run, will end up being more beneficial than difficult work. Out of the part, a basic robotic arm is a standout amongst the most generally introduced machines. Robotic arm is one of the significant undertakings in the present computerization industry. Automated arm is a piece of the mechatronic industry which is a quickly versatile and developing industry today. Distinctive changes and extra features are being associated with the first kind of straightforward robotic arm to upgrade its ease of use under various conditions. In this paper, we are building up a robotic arm which will have a free rotation around multiple axes and we are including the technology of Image Processing with it to make it a visual signal based working robotic arm. The model is a pick and place robotic arm you can take the desired article starting with one place and carry it to another place with its gripper claw. The operations will be constrained by a visual processing framework that reads the gestures and will give directions to the Arm for performing various types of movements and tasks. We are making use of low torque servos to lift light weight. [ABSTRACT FROM AUTHOR]

This study investigates how COVID-19 advice is creatively delivered in a one-minute video produced by the Taiwan Centers for Disease Control in February 2022. It examines metaphors in verbal, visual, and multimodal modes, and illustrates how such metaphors interact with multimodal narrativity. Drawing on the insights of studies on multimodal metaphors, this paper seeks to identify which are the most pervasive metaphors or what dominant metaphor, if any, is used in the video. It finds that the metaphorical mappings between coping with the covid pandemic and handling olympic weightlifting are represented across modes and that the creative delivery of COVID-19 advice is woven from a warp of metaphors in various modes and a weft of narrativity across modes. Such metaphorical creativity is underpinned by the semiotic flow that features four interconnected configurations: moving between metaphorization, literalization, and re-metaphorization; somehow blurring the source-target boundary; expanding the range of functions that the multimodal representation can serve; and initiating a metaphorical thought from one or more contextual factors. [ABSTRACT FROM AUTHOR]

Offshore assembly and disassembly operations represent a multi-billion-dollar market potential. Collaborative lifting by multiple vessels has emerged as a new operating paradigm for integrated offshore facilities assembly and disassembly. Hence, this paper investigates the hydro-dynamic interaction of dual lifting vessels in collaborative lifting operations. The coupled motions during multi-body operations are simulated using the commercial software SESAM. The feasibility of the numerical model for coupled motions in collaborative lifting is verified by comparing the numerical results of topside motions, vessel motions, and vertical lifting arm loads against experimental measurements. The effects of wave heading and period on the hydrodynamic responses of the topside module, dual lifting vessels, and lifting arms during collaborative operations are studied. Their influence patterns and mechanisms are analysed in detail. The results show that transverse waves and head wave induce significant heave and pitch motions of the topside module and vessels, but the maximum vertical loads on the lifting arms occur in oblique waves. The motion responses of the topside module and vessels increase with longer wave periods under the oblique sea condition, and roll motions are more sensitive to large periods compared to the gradual rise in heave and pitch. [ABSTRACT FROM AUTHOR]

This article provides an overview of the advancements in artificial intelligence (AI) over the years. It highlights significant milestones such as the chess match between Gary Kasparov and IBM's DeepBlue supercomputer, as well as the development of AlphaGo and AlphaZero for the game of Go. The article also mentions AlphaFold, a program that predicts protein structures, and the Transformer Neural Network Architecture, which revolutionized natural language processing. It concludes by discussing the recent popularity of large language models like ChatGPT, which can generate coherent responses to text prompts in multiple languages. However, it notes that ChatGPT lacks an understanding of the meaning behind the symbols it generates, and its accuracy improves over time through learning from input. [Extracted from the article]

Based on the theory of sway frame column, the equation of the effective length factor was derived in this paper. Combined with the characteristics of semi-rigid joints, the linear stiffness correction factor of horizontal bar was introduced, and the equation of effective length correction factor was obtained. By using MATLAB programming method, the three-dimensional relationship between the effective length correction factor and the influencing factors was obtained, and the entire process of the stability bearing capacity of the disc-buckle type high support system was described in detail, which improves the stability calculation theory of the high support system. The influence of setting parameters, joint bending stiffness, geometrical size, and material properties on the effective length correction factor is studied. Simultaneously, the joint bending stiffness of semi-rigid joints is determined. The area of the effective length correction factor is analyzed to optimize the design of the setting scheme using horizontal bars and vertical poles of different sizes. The results show that the lift height significantly affects the effective length correction factor during the load bearing process; the factor decreases with increasing lift height. Large transverse and longitudinal distances influence this rule during the initial load bearing. When the joint bending stiffness is less than 100 (kN·m)/rad, the effective length correction factor decreases rapidly with an increase in joint bending stiffness. When the joint bending stiffness is greater than 100 (kN·m)/rad, the effective length correction factor is unaffected by the joint bending stiffness. When the joint bending stiffness is large at initiation of loading, the effective length correction factor decreases with an increase in the outer diameter of the horizontal bar. When the joint bending stiffness is small, the effective length correction factor increases with an increase in the section size of the vertical pole. Therefore, the outer diameter of the horizontal bar significantly affects the effective length correction factor, and a larger diameter is more conducive to the overall stability. Furthermore, the elastic modulus effects the effective length correction factor for the unstable support system. [ABSTRACT FROM AUTHOR]

Copyright of Retos: Nuevas Perspectivas de Educación Física, Deporte y Recreación is the property of Federacion Espanola de Asociaciones de Docentes de Educacion Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper is devoted to the problem of counting repetitions and automatic weight stack detection in a weightlifting machine used for weight training. Some weightlifting machines include a weight stack that can be adjusted by a user. For example, the user can choose to increase or reduce the weight load using the weight stack, thus changing the difficulty level of a particular exercise. Users may want to perform a desired number of repetitions of an exercise or to perform an exercise with a desired range of motion when using such weightlifting machines. From a medical point of view, it is often required that an exact number of repetitions of a given load are performed in order to aid in a prompt recovery. This paper describes a complete design of the system and the algorithm that allows one to collect data from such a machine. Data can then be used for various purposes: in overviews and statistical analysis of a number of workouts. The approach presented in this paper is part of an application for European patent number 18461537.5-1126. [ABSTRACT FROM AUTHOR]