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1.
Rev. bras. med. esporte ; 30: e2021_0505, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1441309

ABSTRACT

ABSTRACT Introduction: Submaximal strength testing appears to be valid to prescribe the intensity for strength training protocols that reduce the risk of injuries and testing time. Objective: This study aimed to assess the predictive ability of body mass parameters to estimate 4-6 repetitions maximum (4-6 RM) of Leg press 45°, Chest press, and Pull-down exercises. Methods: Eleven male bodybuilders (age 38.27 ± 10.48 years) participated in this study. Participants completed an incremental external load up to find the load allowing them to perform 4 to 6 maximal repetitions for each exercise in random order. The starting load was 50% of body mass for chest press and pull-down exercises and 100% for leg press. The load increment after each set was 20 kg for lower limb exercises and 10 kg for upper body exercises. Results: Results revealed that body mass had good to optimal relationships with 4-6 RM for all three exercises. Results showed that body mass had a good prediction ability for all three criterion measures. Conclusion: The prediction equations suggested in this study may allow coaches to estimate the 4-6 RM of leg press 45°, chest press, and pull-down performances. Evidence Level IV; Case series.


RESUMEN Introducción: El test de fuerza submáxima parece ser válido para prescribir la intensidad en protocolos de entrenamiento de fuerza, reduciendo el riesgo de lesiones y la duración del test. Objetivo: Evaluar la capacidad predictiva de los parámetros de masa corporal para estimar 4-6 repeticiones máximas (4-6 RM) de ejercicios de Leg press 45°, Chest press y Pull-down realizados por fisicoculturistas. Métodos: Once fisicoculturistas masculinos (38,27 ± 10,48 años) participaron en el estudio. Completaron la carga externa incremental hasta encontrar la carga que les permitiera realizar de 4 a 6 repeticiones máximas para cada ejercicio, en orden aleatorio. La carga inicial se fijó en el 50% de la masa corporal para los ejercicios Chest press y Pull-down, y en el 100% para los ejercicios Leg press. El incremento de carga después de cada ronda fue de 20 kg para los miembros inferiores y 10 kg para los miembros superiores. Resultados: Los resultados revelaron que la masa corporal tiene relaciones satisfactorias con 4-6 RM para los tres ejercicios. Los resultados mostraron que la masa corporal tiene una buena capacidad predictiva en las tres medidas. Conclusión: Las ecuaciones de predicción sugeridas en este estudio pueden permitir a los entrenadores utilizar estos ejercicios para medir el rendimiento a 4-6 RM en ejercicios de Leg press 45°, Chest press y Pull-down. Nivel de Evidencia IV; serie de casos.


RESUMO Introdução: O teste de força submáxima parece ser válido para prescrever a intensidade nos protocolos de treinamento de força, reduzindo o risco de lesões e duração dos testes. Objetivo: Avaliar a capacidade preditiva dos parâmetros de massa corporal para estimar o exercício de 4-6 repetições máximas (4-6 RM) nos exercícios de Leg press 45°, Chest press e Pull-down efetuados por fisiculturistas. Métodos: Onze fisiculturistas masculinos (38,27 ± 10,48 anos) participaram do estudo. Eles completaram a carga externa incremental até encontrar a carga que lhes permitia realizar de 4 a 6 repetições máximas para cada exercício, em ordem aleatória. A carga inicial foi fixada em 50% da massa corporal para os exercícios de Chest press e Pull-down, e 100% para o de Leg press. O incremento de carga após cada rodada foi de 20 kg para o exercício de membros inferiores e 10 kg em membros superiores. Resultados: Os resultados revelaram que a massa corporal apresenta relações satisfatórias com 4-6 RM para todos os três exercícios. Os resultados mostraram que a massa corporal possui boa capacidade preditiva em todas as três medidas. Conclusão: As equações de previsão sugeridas nesse estudo podem permitir o uso desses exercícios pelos técnicos para medir a performance a 4-6 RM nos exercícios de Leg press 45°, Chest press, e Pull-down. Nível de evidência IV; série de casos.

2.
Molecules ; 26(1)2021 Jan 04.
Article in English | MEDLINE | ID: mdl-33406792

ABSTRACT

The theoretical study of chrysanthemin (cyanidin 3-glucoside) as a pigment for TiO2-based dye-sensitized solar cells (DSSCs) was performed with the GAUSSSIAN 09 simulation. The electronic spectra of neutral and anionic chrysanthemin molecules were calculated by density functional theory with B3LYP functional and DGDZVP basis set. A better energy level alignment was found for partially deprotonated molecules of chrysanthemin, with the excited photoelectron having enough energy in order to be transferred to the conduction band of TiO2 semiconductor in DSSCs. In addition, we used the raw aqueous extracts of roselle (Hibiscus sabdariffa) calyces as the source of chrysanthemin and the extracts with various pH values were tested in DSSCs. The extracts and photosensitized semiconductor layers were characterized by UV-Vis spectroscopy, and DSSCs based on raw extracts were characterized by current density-voltage measurements.


Subject(s)
Chrysanthemum/chemistry , Coloring Agents/chemistry , Computer Simulation , Electric Power Supplies , Plant Extracts/chemistry , Solar Energy , Titanium/chemistry
3.
Nanomaterials (Basel) ; 9(5)2019 May 15.
Article in English | MEDLINE | ID: mdl-31096586

ABSTRACT

We report on the fabrication of dye-sensitized solar cells with a TiO2 buffer layer between the transparent conductive oxide substrate and the mesoporous TiO2 film, in order to improve the photovoltaic conversion efficiency of the device. The buffer layer was fabricated by pulsed laser deposition whereas the mesoporous film by the doctor blade method, using TiO2 paste obtained by the sol-gel technique. The buffer layer was deposited in either oxygen (10 Pa and 50 Pa) or argon (10 Pa and 50 Pa) onto transparent conducting oxide glass kept at room temperature. The cross-section scanning electron microscopy image showed differences in layer morphology and thickness, depending on the deposition conditions. Transmission electron microscopy studies of the TiO2 buffer layers indicated that films consisted of grains with typical diameters of 10 nm to 30 nm. We found that the photovoltaic conversion efficiencies, determined under standard air mass 1.5 global (AM 1.5G) conditions, of the solar cells with a buffer layer are more than two times larger than those of the standard cells. The best performance was reached for buffer layers deposited at 10 Pa O2. We discuss the processes that take place in the device and emphasize the role of the brush-like buffer layer in the performance increase.

4.
Maedica (Bucur) ; 6(2): 132-6, 2011 Apr.
Article in English | MEDLINE | ID: mdl-22205896

ABSTRACT

BACKGROUND: Tetrasomy 18p is a very rare chromosomal disorder and is the result of a spontaneous mutation early in embryonic development in most of the cases. This condition is characterised by the presence of a supernumerary 18p isochromosome (i(18p)) in all or some cells of the affected individual. It has a prevalence of 1/180000 live births and affects both genders equally. MATERIALS AND METHODS: In this paper we report a de novo tetrasomy 18p in a 3 months old female dysmorphic child. The clinical features were distinctive with a particular facies, strabismus, microcephaly, growth delay, neonatal hypertonia and talipes varus. An additional small metacentric marker chromosome has been identified after standard cytogenetic analysis, without recognized parental origin of the supplementary genetic material. The child's parents were also tested and their karyotype results were normal. The characterization of the marker chromosome was performed in our genetics laboratory using conventional cytogenetic methods and Fluorescence in Situ Hybridization (FISH) analysis. Also, our patient was compared with other published cases with the same diagnosis. CONCLUSION: Cytogenetic investigation is an essential step towards the accurate diagnosis of individuals with clinical suspicion of a genetic anomaly. Also, this type of investigation could offer critical information to the practitioner for prognosis of patient and the correct appreciation of the recurrence risk of a certain genetic condition.With current advances in preventive and interventional procedures, patients with rare chromosomal disorders can live longer. Therefore, proper medical and behavioural management of each case is important for the enhancement of the quality of life for the patients and their families.

5.
Maedica (Bucur) ; 5(3): 178-85, 2010 Jul.
Article in English | MEDLINE | ID: mdl-21977150

ABSTRACT

INTRODUCTION: Patau syndrome (trisomy 13) is one of the most common chromosomal anomalies clinically characterized by the presence of numerous malformations with a limited survival rate for most cases. Babies are usually identified at birth and the diagnosis is confirmed with genetic testing. MATERIALS AND METHODS: In this review we outline the clinical and cytogenetic aspects of trisomy 13 and associated phenotypes for 5 cases analyzed in the last 3 years, referred to our Clinical Genetics Department. For each child cytogenetic analysis was performed to determine the genetic variant; also, the patients were investigated for other associated malformations (cardiac, cerebral, renal, ocular anomalies). DISCUSSION: All 5 cases presented multiple malformations, including some but not all signs of the classical clinical triad suggestive of Patau syndrome. The cytogenetic investigation confirmed for each case the suspected diagnosis and also indicated the specific genetic variant, this being a valuable information for the genetic counselling of the families. CONCLUSION: The application of genetic analysis can increase diagnosis and prognosis accuracy and have an impact on clinical management.

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