Designing process and analysis of a new SOI-MESFET structure with enhanced DC and RF characteristics for high-frequency and high-power applications.

This research introduces a new designing process and analysis of an innovative Silicon-on-Insulator Metal-Semiconductor Field-Effect (SOI MESFET) structure that demonstrates improved DC and RF characteristics. The design incorporates several modifications to control and reduce the electric field concentration within the channel. These modifications include relocating the transistor channel to sub-regions near the source and drain, adjusting the position of the gate electrode closer to the source, introducing an aluminum layer beneath the channel, and integrating an oxide layer adjacent to the gate. The results show that the AlOx-MESFET configuration exhibits a remarkable increase of 128% in breakdown voltage and 156% in peak power. Furthermore, due to enhanced conductivity and a significant reduction in gate-drain capacitance, there is a notable improvement of 53% in the cut-off frequency and a 28% increase in the maximum oscillation frequency. Additionally, the current gain experiences a boost of 15%. The improved breakdown voltage and peak power make it suitable for applications requiring robust performance under high voltage and power conditions. The increased maximum oscillation frequency and cut-off frequency make it ideal for high-frequency applications where fast signal processing is crucial. Moreover, the enhanced current gain ensures efficient amplification of signals. The introduced SOI MESFET structure with its modifications offers significant improvements in various performance metrics. It provides high oscillation frequency, better breakdown voltage and good cut-off frequency, and current gain compared to the traditional designs. These enhancements make it a highly desirable choice for applications that demand high-frequency and high-power capabilities.

Resistance training & beta-hydroxy-beta-methylbutyrate supplementation on hormones / Treinamento de resistência e suplementação de beta-hidroxi-beta-metilbutirato em hormônios / Entrenamiento de resistencia y suplementación de beta-hidroxi-beta-metilbutirato en hormonas

RESUMOIntroduction:In recent years, there was an increased interest on the effects of beta-hydroxy-beta-methylbutyrate (HMB) supplementation on skeletal muscle due to its anti-catabolic effects.Objectives:To investigate the effect of HMB supplementation on body composition, muscular strength and anabolic-catabolic hormones after resistance training.Methods:Twenty amateur male athletes were randomly assigned to supplement and control groups in a double-blind crossover design and participated in four weeks resistance training. Before and after the test period fasting blood samples were obtained to determine anabolic (the growth hormone and testosterone) and catabolic (cortisol) hormones, and fat mass, lean body mass (LBM) and muscular strength were measured. Dependent and independent t-tests were used to analyze data.Results:After the training period, there were no significant differen-ces between the groups with respect to fat mass, LBM and anabolic-catabolic hormones. HMB supplementation resulted in a significantly greater strength gain (p≤0.05).Conclusion:Greater increase in strength for HMB group was not accompanied by body composition and basal circulating anabolic-catabolic hormonal changes. It seems that HMB supplementation may have beneficial effects on neurological adaptations of strength gain.

ABSTRACTIntrodução:Nos últimos anos, houve um aumento no interesse sobre os efeitos da suplementação de beta-hidroxi--beta-metilbutirato (HMB) no musculoesquelético devido aos seus efeitos anticatabólicos.Objetivos:Investigar o efeito da suplementação de HMB na composição corporal, força muscular e hormônios anabólicos-catabólicos após treinamento de resistência.Métodos:Vinte atletas amadores do sexo masculino foram aleatoriamente designados a grupos de su-plemento e de controle em design cruzado duplo-cego, tendo participado de treinamento de resistência durante quatro semanas. Antes e depois do período de teste, foram obtidas amostras de sangue em jejum para determinar os hormônios anabólicos (o hormônio do crescimento e a testosterona) e catabólico (cortisol), tendo a massa adiposa, massa corporal magra (LBM) e força muscular sido mensuradas. Testes t dependentes e independentes foram usados para analisar os dados.Resultados:Após o período de treinamento, não houve nenhuma diferença significativa entre os grupos no que diz respeito à massa adiposa, LBM e hormônios anabólicos-catabólicos. A suplementação de HMB resultou em um ganho de força significativamente maior (p<0,05).Conclusão:O maior aumento na força no grupo HMB não foi acompanhado por alterações na composição corporal e alterações hormonais anabólicas-catabólicas basais na circulação. Parece que a suplementação de HMB pode ter efeitos benéficos sobre as adaptações neurológicas do ganho de força.

RESUMENIntroducción:En los últimos años hubo un aumento en el interés sobre los efectos de la suplementación de beta-hidroxi-beta-metilbutirato (HMB) en el músculo esquelético debido a sus efectos anticatabólicos.Objetivos:Investigar el efecto de la suplementación de HMB en la composición corporal, fuerza muscular y hormonas ana-bólicas-catabólicas después de entrenamiento de resistencia.Métodos:Veinte atletas amateurs del sexo masculino fueron aleatoriamente designados a grupos de suplemento y de control en un diseño cruzado doble ciego, habiendo participado en entrenamiento de resistencia durante cuatro semanas. Antes y después del período de test, fueron obtenidas muestras de sangre en ayunas para determinar las hormonas anabólicas (la hormona del crecimiento y la testosterona) y catabólica (cortisol), habiendo sido medidas la masa adiposa, masa corporal magra (LBM) y fuerza muscular. Los Tests-t dependientes e independientes fueron usados para analizar los datos.Resultados:Des-pués del período de entrenamiento, no hubo ninguna diferencia significativa entre los grupos en lo que se refiere a la masa adiposa, LBM y hormonas anabólicas-catabólicas. La suplementación de HMB resultó en un aumento de fuerza significativamente mayor (p<0,05).Conclusión:El mayor aumento en la fuerza en el grupo HMB no fue acompañado por alteraciones en la composición corporal y alteraciones hormonales anabólicas-catabólicas ba-sales en la circulación. Parece que la suplementación de HMB puede tener efectos benéficos sobre las adaptaciones neurológicas del aumento de fuerza.

Effects of Different Rest Intervals between Circuit Resistance Exercises on Post-exercise Blood Pressure Responses in Normotensive Young Males.

PURPOSE: To investigate the blood pressure responses during recovery after two protocols of circuit resistance exercises (CRE) with different rest intervals (RI). METHODS: Eleven normotensive males (aged 19.5 ± 1.0 yrs, height 172.8 ± 5.7 cm and weight 65.1 ± 8.1 kg) performed two CRE with RI of 30 (RI30s) and 40 (RI40s) seconds between the exercises randomly, as well as a control session without exercise. The protocols consisted of 3 circuits of 6 exercises with 10 repetitions maximum (10RM) and 2 minute rest between circuits, followed by an 80 minute recovery period. Measurements were taken before exercise and at each 10 min of post-exercise recovery. The Analysis of Variance (ANOVA) with Repeated Measures (group × time) was used to analyze data, followed by post-hoc Bonferroni test, for P≤0.05. RESULTS: Post-exercise hypotension of systolic blood pressure was observed after both CRE with RI30s and RI40s (at R40, R50, R60, R70 and R80), whereas diastolic blood pressure did not differ from that measured at rest. In all measured moments, there was no significant difference between exercise trials in post-exercise levels of systolic and diastolic blood pressure. CONCLUSION: CRE with RI30s and RI40s between the exercises can lead to occurrence of PEH similarly in magnitude and duration. Our findings suggest a potentially positive health benefit of strength training.

Estudo comparativo de respostas cardiovasculares para dois intervalos de recuperação entre exercícios resistidos em circuito em mulheres normotensas / A comparative study of cardiovascular responses to two rest intervals between circuit resistance exercises in normotensive women

INTRODUÇÃO: A hipertensão é uma desordem cardiovascular que acomete aproximadamente um bilhão de indivíduos no mundo e representa um importante fator de risco para doença cardiovascular. OBJETIVO: Comparar as respostas cardiovasculares durante recuperação após dois protocolos de exercícios resistidos em circuito (ERC) com diferentes intervalos de recuperação (IR). Doze mulheres normotensas (idade 21,3 ± 1,3, anos; altura 163,5 ± 5,9 cm e peso 57,5 ± 8,9 kg) executaram dois ERC com IR de 30 (IR30s) e 40 (IR40s) segundos entre os exercícios, aleatoriamente. MÉTODOS: Os protocolos consistiram de três circuitos de seis exercícios com 10 repetições máximas (10RM) e dois minutos de recuperação entre os circuitos, seguidos por um período de recuperação ode 60 minutos. As medidas foram tomadas antes do exercício, ao fim do último exercício (R1) e a cada 10 minutos de recuperação pós-exercício (R10, R20, R30, R40, R50 e R60). Análise de variância de medidas repetidas (ANOVA) (grupo x tempo) foi utilizada para analisar os dados, seguida pelo teste post-hoc de Bonferroni, para p ≤ 0,05. RESULTADOS: Em comparação com os valores de recuperação, pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), frequência cardíaca (FC) e produto da taxa de pressão (PTP) em R1 após as tentativas de exercício com IR30s e IR40s aumentaram significativamente. Hipotensão pós-exercício (HPE) de PAS foi observada após ERC com IR30s (em R20, R30, R40, R50 e R60) e IR40s (em R30, R40, R50 e R60), enquanto HPE de PAD foi observada somente após ERC com IR30s em R60. Exceto por tempo após ERC com IR30s em R10, nenhuma alteração significativa de FC foi observada em todos os momentos medidos durante os períodos de recuperação das tentativas. PTP retornou aos valores de repouso após as tentativas de exercício em R10, diminuindo significativamente após ERC com IR30s em R60 e após ERC com IR40s em R40, R50 e R60. CONCLUSÃO: Nenhuma diferença significativa foi encontrada entre as sessões experimentais em níveis pós-exercício de PAS, PAD, FC e PTP em quaisquer dos momentos de medição. Podemos concluir que ERC com IR30s e IR40s entre exercícios pode levar à ocorrência de HPE semelhante à magnitude e duração e fornece respostas cardiovasculares aproximadamente similares após exercício. Nossos achados sugerem um possível benefício para a saúde do treinamento de força.

INTRODUCTION: Hypertension is a cardiovascular disorder which occurs in approximately one billion individuals worldwide and represents an important risk factor for cardiovascular disease. OBJECTIVE: Compare the cardiovascular responses during recovery after two protocols of circuit resistance exercises (CRE) with different rest intervals (RI). Twelve normotensive females (aged 21.3 ± 1.3, yrs; height 163.5 ± 5.9 cm and weight 57.5 ± 8.9 kg) performed two CRE with RI of 30 (RI30s) and 40 (RI40s) seconds between the exercises, randomly. METHODS: The protocols consisted of three circuits of six exercises with 10 repetition maximum (10RM) and 2 minute rest between circuits, followed by a 60 minute recovery period. Measurements were taken before exercise, at the end of last exercise (R1) and each 10 min of post-exercise recovery (R10, R20, R30, R40, R50 and R60). The Analysis of Variance (ANOVA) with Repeated Measures (group × time) was used to analyze of data, followed by post-hoc Bonferroni test, for p≤0.05. RESULTS: In comparison of rest values, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and rate pressure product (RPP) at R1 after exercise trials with RI30s and RI40s increased significantly. Post-exercise hypotension (PEH) of SBP was observed after CRE with RI30s (at R20, R30, R40, R50 and R60) and RI40s (at R30, R40, R50 and R60), whereas PEH of DBP observed only after CRE with RI30s at R60. Except for time after CRE with RI30s at R10, no significant change of HR was observed in all measured moments during recovery period of trials. RPP returned to the rest values after exercise trials at R10 and then decreased significantly after CRE with RI30s at R60 and after CRE with RI40s at R40, R50 and R60. CONCLUSION: In all measured moments, there were no significant differences between experimental sessions in post-exercise levels of SBP, DBP, HR and RPP. In conclusion, CRE with RI30s and RI40s between the exercises can lead to occurrence of PEH similarly in magnitude and duration and approximately provides same cardiovascular responses after exercise. Our findings suggest a potentially positive health benefit of strength training.

Concurrent Brucellosis and Q Fever Infection: a Case Control Study in Bamyan Province, Afghanistan.

BACKGROUND: More than 500,000 people are affected by brucellosis each year while the incidence of Q fever is poorly recorded. Consistent outbreaks of brucellosis have been reported in Afghanistan, affecting social and economic life. This study aimed to determine the means of propagation of brucellosis and Q-fever and establish appropriate control measures for both. METHODS AND MATERIALS: An outbreak of 1,317 cases of brucellosis and Q fever was investigated from May 2011 to the end of 2012 in Bamyan province of Afghanistan. A total of 100 cases were selected by random sampling with equal number of neighbor controls. Data were collected through structured questionnaire. RESULTS: The average age was 30 years ±14 years. Of those sampled, 62% were female, 38% were male, and resided in three districts: Punjab, Yakawlang and Waras. Using multivariate analysis, being a housewife (OR=7.36), being within proximity of kitchens to barns (OR= 2.98), drinking un-boiled milk (OR= 5.26), butchering (OR= 3.53) and purchasing new animals in the last six months (OR= 3.53) were significantly associated with contraction of brucellosis and Q fever. CONCLUSION: Health educators should focus on families dealing with animals, especially on females. Pasturing, healthy milking, dunging, and slaughtering practices, along with use of safe dairy products should be the focus of preventive measures.