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1.
BMC Public Health ; 24(1): 826, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491432

RESUMEN

BACKGROUND: Regular participation in physical activity (PA) benefits children's health and well-being and protects against the development of unhealthy body weight. A key factor in children's PA participation is their motor competence (MC). The comprehensive school physical activity program (CSPAP) framework offers a way to classify existing PA interventions that have included children's MC development and understand the potential avenues for supporting children's MC. However, there have been no systematic reviews or meta-analyses of PA interventions and their effects on the MC of elementary school children (aged 5-12 years) from a CSPAP perspective. METHODS: This study was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. We searched seven electronic databases (PubMed/Medline, Embase, ERIC, SPORTDiscus, CINAHL, Web of Science, and PsycINFO) for articles on 29 November 2021. The CSPAP framework was used to categorize the different intervention approaches. This review was registered with PROSPERO (CRD42020179866). RESULTS: Twenty-seven studies were included in the review, and twenty-six studies were included in the meta-analysis. A wide range of PA intervention approaches (e.g., single component or multicomponent) within the context of the CSPAP framework appear to be promising pathways in enhancing children's MC. The results of the aggregate meta-analysis presented that effect sizes for the development of MC from pre-and post- intervention ranged from moderate to large (Hedges' g = 0.41-0.79). The analysis revealed that the predicted moderators, including study length, delivery agent, and study design, did not result in statistically significant moderate variations in MC outcomes. There was, however, considerable heterogeneity in study design, instruments, and study context, and studies were implemented in over 11 countries across diverse settings. CONCLUSIONS: This study uniquely contributes to the literature through its primary focus on the effectiveness of PA interventions on elementary children's MC. This review emphasizes the importance of customizing CSPAP to fit the specific characteristics of each school setting, including its environmental, demographic, and resource attributes. The effectiveness of CSPAP, particularly its physical education (PE) component, is significantly enhanced when these programs are adapted to address the unique needs of each school. This adaptation can be effectively achieved through targeted professional teacher training, ensuring that PE programs are not only contextually relevant but also optimized for maximum impact in diverse educational environments. Researchers and practitioners should pursue how to effectively translate the evidence into practice to better conceptualize CSPAPs designed for children's MC development.


Asunto(s)
Ejercicio Físico , Humanos , Niño , Preescolar , Servicios de Salud Escolar , Promoción de la Salud/métodos , Destreza Motora/fisiología , Instituciones Académicas
2.
BMC Public Health ; 23(1): 2089, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880639

RESUMEN

BACKGROUND: Guided by Self-Determination Theory (SDT), the purpose of this study was to determine changes in the 16-week moderate-to-vigorous physical activity (MVPA) trajectory of underserved adolescents who participated in the Connect through PLAY afterschool program intervention and the effects of changes in participating adolescents' intrinsic and autonomous extrinsic motivations on their MVPA trajectory over the 16-week intervention. METHODS: A subsample of 113 adolescents (56.64% female; 61.06% African American; average age = 11.29) provided complete data throughout the 16-week intervention were examined. Adolescents' objective daily MVPA was measured using 7- day accelerometer data. Changes in adolescents' intrinsic motivation and autonomous extrinsic motivation were assessed using subscales from the Intrinsic Motivation Inventory [1] and the Treatment Self-Regulation Questionnaire [2] respectively. A hierarchical linear model was built and tested to address the research aims. RESULTS: The results of hierarchical linear models showed that, on average, youth daily MVPA increased 6.36 minutes in each 8-week period. Intrinsic motivation change, but not autonomous extrinsic motivation, was a positive and significant level-2 predictor of daily MVPA changes. CONCLUSION: The findings provide significant evidence suggesting a benefit of integrating SDT-based approaches and further suggest that nurturing intrinsic motivation can be an effective approach to supporting youth daily MVPA in under-resourced afterschool programs. TRIAL REGISTRATION: Connect Through PLAY: A Staff-based Physical Activity Intervention for Middle School Youth (Connect). https://clinicaltrials.gov/ct2/show/NCT03732144 . Registered November 6th, 2018.


Asunto(s)
Ejercicio Físico , Motivación , Adolescente , Niño , Femenino , Humanos , Masculino , Terapia Conductista , Instituciones Académicas , Encuestas y Cuestionarios
3.
J Sports Sci ; 41(6): 502-511, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37322573

RESUMEN

The purpose of this study was to investigate the influences of intrinsic motivation, social affiliation orientations and reciprocal social support for physical activity (PA) on underserved youths' afterschool period moderate-to-vigorous (MVPA) changing trajectories across the 16-week Connect through PLAY intervention, a social-motivational climate intervention. A total of 113 youth (61.06% African American, 56.64% girls) provided full data. Youths' intrinsic motivation, social affiliation orientations and social support were measured by youth responses to a set of surveys at baseline and post-intervention. Youths' afterschool period MVPA was measured using data from 7-day ActiGraph accelerometer wear at baseline, midpoint and post-intervention. Hierarchical linear modelling analysis found that youth daily afterschool period (3pm-6pm) MVPA increased, on average, 37.94 min across the 16-week intervention. Increases in intrinsic motivation, social affiliation orientations and social support were positive predictors of youth afterschool MVPA changing trajectory. The findings clarify the contributions that a social-motivational climate intervention can have on youth afterschool period MVPA through increasing youth intrinsic motivation, social affiliation and reciprocal social support.


Asunto(s)
Motivación , Medio Social , Femenino , Humanos , Adolescente , Masculino , Ejercicio Físico , Apoyo Social , Encuestas y Cuestionarios
4.
Sensors (Basel) ; 17(3)2017 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-28335572

RESUMEN

At present, users can utilize an authenticated key agreement protocol in a Wireless Sensor Network (WSN) to securely obtain desired information, and numerous studies have investigated authentication techniques to construct efficient, robust WSNs. Chang et al. recently presented an authenticated key agreement mechanism for WSNs and claimed that their authentication mechanism can both prevent various types of attacks, as well as preserve security properties. However, we have discovered that Chang et al's method possesses some security weaknesses. First, their mechanism cannot guarantee protection against a password guessing attack, user impersonation attack or session key compromise. Second, the mechanism results in a high load on the gateway node because the gateway node should always maintain the verifier tables. Third, there is no session key verification process in the authentication phase. To this end, we describe how the previously-stated weaknesses occur and propose a security-enhanced version for WSNs. We present a detailed analysis of the security and performance of our authenticated key agreement mechanism, which not only enhances security compared to that of related schemes, but also takes efficiency into consideration.

5.
Sensors (Basel) ; 17(5)2017 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-28441331

RESUMEN

User authentication in wireless sensor networks is more difficult than in traditional networks owing to sensor network characteristics such as unreliable communication, limited resources, and unattended operation. For these reasons, various authentication schemes have been proposed to provide secure and efficient communication. In 2016, Park et al. proposed a secure biometric-based authentication scheme with smart card revocation/reissue for wireless sensor networks. However, we found that their scheme was still insecure against impersonation attack, and had a problem in the smart card revocation/reissue phase. In this paper, we show how an adversary can impersonate a legitimate user or sensor node, illegal smart card revocation/reissue and prove that Park et al.'s scheme fails to provide revocation/reissue. In addition, we propose an enhanced scheme that provides efficiency, as well as anonymity and security. Finally, we provide security and performance analysis between previous schemes and the proposed scheme, and provide formal analysis based on the random oracle model. The results prove that the proposed scheme can solve the weaknesses of impersonation attack and other security flaws in the security analysis section. Furthermore, performance analysis shows that the computational cost is lower than the previous scheme.

6.
Dig Endosc ; 28(5): 592-8, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26836784

RESUMEN

BACKGROUND AND AIM: A reproducible in vivo swine model of bile duct dilation (BDD) was recently established and reported for preclinical testing of newly developed biliary devices or endoscopic techniques. The aim of the present study was to develop a more advanced large animal model in which it is possible to direct examination of the biliary tree. Methods Six mini pigs were prepared for the study. BDD models were first made by closure of the Vater's ampulla in all swine. Then endoscopic papillary balloon dilation (EPBD) was done in the animals. Feasibility of single-operator peroral cholangioscopy without assistance of accessories was evaluated using an ultra-slim upper endoscope in the animals. Results EPBD could be implemented using a dilation balloon catheter (10~13.5 mm) in all BDD models (6/6, 100%). Success rate of freehand direct insertion of an ultra-slim endoscope into the common bile duct was 100% (6/6), and access to the common hepatic duct with examination was possible using direct peroral cholangioscopy in five animals (5/6, 83.3%). None of the animals died. In the cholangioscopic examination, a bile duct polyp and a benign biliary stricture occurred naturally, respectively, in two of the six swine. Conclusion An in vivo swine model of biliary dilatation-based direct peroral cholangioscopy was established. This novel animal model may be useful for preclinical research of new materials or devices because direct visualization of the biliary tree is feasible.


Asunto(s)
Ampolla Hepatopancreática/diagnóstico por imagen , Ampolla Hepatopancreática/cirugía , Angioscopía , Cirugía Endoscópica por Orificios Naturales , Animales , Dilatación , Modelos Animales de Enfermedad , Estudios de Factibilidad , Porcinos
7.
J Med Syst ; 40(3): 70, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26743628

RESUMEN

Recently, numerous extended chaotic map-based password authentication schemes that employ smart card technology were proposed for Telecare Medical Information Systems (TMISs). In 2015, Lu et al. used Li et al.'s scheme as a basis to propose a password authentication scheme for TMISs that is based on biometrics and smart card technology and employs extended chaotic maps. Lu et al. demonstrated that Li et al.'s scheme comprises some weaknesses such as those regarding a violation of the session-key security, a vulnerability to the user impersonation attack, and a lack of local verification. In this paper, however, we show that Lu et al.'s scheme is still insecure with respect to issues such as a violation of the session-key security, and that it is vulnerable to both the outsider attack and the impersonation attack. To overcome these drawbacks, we retain the useful properties of Lu et al.'s scheme to propose a new password authentication scheme that is based on smart card technology and requires the use of chaotic maps. Then, we show that our proposed scheme is more secure and efficient and supports security properties.


Asunto(s)
Identificación Biométrica/métodos , Seguridad Computacional , Tarjetas Inteligentes de Salud/métodos , Sistemas de Información/normas , Telemedicina/normas , Confidencialidad , Humanos , Dinámicas no Lineales
8.
Pancreatology ; 15(4): 405-10, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25998516

RESUMEN

BACKGROUND/OBJECTIVES: Prediction of malignancy in patients with BD-IPMNs is critical for the management. The aim of this study was to elucidate predictors of malignancy in patients with 'pure' BD-IPMNs who had a main pancreatic duct (MPD) diameter of ≤5 mm according to the most recent international consensus criteria and in whom MPD involvement was excluded on postoperative histology. METHODS: We identified 177 patients with 'pure' BD-IPMNs based on preoperative imaging and postoperative histology from 15 tertiary referral centers in Korea. BD-IPMNs with low-grade (n = 72) and moderate-grade (n = 66) dysplasia were grouped as benign and BD-IPMNs with high-grade dysplasia (n = 10) and invasive carcinoma (n = 29) were grouped as malignancy. RESULTS: On univariate analysis, particular symptoms (jaundice and clinical pancreatitis), CT findings (cyst size > 3 cm, the presence of enhancing mural nodules) and EUS features (the presence of mural nodules, the mural nodule size > 5 mm) were significant risk factors predicting malignant BD-IPMNs. Multivariate analysis revealed that the cyst size > 3 cm (odds ratio = 9.9), the presence of enhancing mural nodules on CT (odds ratio = 19.3) and the mural nodule size > 5 mm on EUS (odds ratio = 14.9) were the independent risk factors for the presence of malignancy in BD-IPMNs (p < 0.001). CONCLUSIONS: The cyst size > 3 cm, the presence of enhancing mural nodules on CT, the mural nodule size > 5 mm on EUS are three independent predictors of malignancy in patients with 'pure' BD-IPMNs.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/patología , Papiloma Intraductal/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Invasividad Neoplásica/patología , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/epidemiología , Papiloma Intraductal/diagnóstico , Papiloma Intraductal/epidemiología , Valor Predictivo de las Pruebas , Curva ROC , República de Corea/epidemiología , Factores de Riesgo
9.
Artículo en Inglés | MEDLINE | ID: mdl-36429750

RESUMEN

Physical education (PE) is beneficial for the development of elementary school-age children through its promotion of different educational learning outcomes, which in turn affects the long-term development of physically active lifestyles. In many countries, PE is taught by classroom teachers (CTs), who are thought to be in a unique position to positively impact students' learning. While a substantial body of studies examines the challenges that CTs encounter when teaching PE, less research has been directed towards gaining a comprehensive understanding of how CTs visualize PE and, in turn, how to promote various types of PE. The purpose of this study, therefore, was to explore elementary school CTs' beliefs about and practices in PE in South Korea. To achieve the research goal, a semi-structured face-to face interview with six CTs was performed to collect the qualitative data source, using the ground theory as an analysis method. Three themes emerged from these interviews concerning the CTs' beliefs in PE: (a) the importance of understanding students' characteristics, (b) the importance of centering internal perceptions in PE method, and (c) the importance of meaningful experiences. The results also identified two themes for teaching practices in PE that corresponded to CTs' beliefs: (a) crafting personalized instructional methods and (b) connecting PE experiences. This study lends important insights to future practices and research recommendations for CTs' PE teaching and teacher education programs.


Asunto(s)
Educación y Entrenamiento Físico , Maestros , Niño , Humanos , Instituciones Académicas , Estudiantes , Motivación
10.
Artículo en Inglés | MEDLINE | ID: mdl-34360072

RESUMEN

Over the past few decades, studies have emphasized improving children's health by increasing health-related fitness levels. Despite the known benefits of health-related fitness in youth, studies have also highlighted a lack of physical activity opportunities for children living in low-income households. The purpose of this study was to investigate the health-related fitness levels of students attending Title I (low-income) elementary schools. A total of 77 elementary students (50.6% female; Mage = 10.0, SD = 0.827) from two Title I elementary schools in the western United States completed the FitnessGram assessments of aerobic capacity, muscular strength and endurance, and flexibility. Descriptive statistics were used to identify the number of students in the Healthy Fitness Zone (HFZ) based upon the FitnessGram HFZ Performance Standards. Less than 17% of students achieved the HFZ for aerobic capacity and only 31.2% achieved the HFZ for upper body strength and endurance. Students performed better for abdominal strength and endurance and flexibility with 55.8% and 68.8% achieving the HFZ, respectively. The results of this study offer insights into the health-related fitness levels of a unique population, students attending Title I schools. School health professionals, including physical education teachers, need to be aware of existing disparities and make efforts to systematically intervene.


Asunto(s)
Ejercicio Físico , Aptitud Física , Adolescente , Índice de Masa Corporal , Niño , Femenino , Humanos , Masculino , Instituciones Académicas , Estudiantes , Estados Unidos
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