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1.
ACS Catal ; 14(7): 4768-4785, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38601779

RESUMO

Recently, there has been a growing interest in using MOF templating to synthesize heterogeneous catalysts based on metal nanoparticles on carbonaceous supports. Unlike the common approach of direct pyrolysis of PdIn-MOFs at high temperatures, this work proposes a reductive chemical treatment under mild conditions before pyrolysis (resulting in PdIn-QT). The resulting material (PdIn-QT) underwent comprehensive characterization via state-of-the-art aberration-corrected electron microscopy, N2 physisorption, X-ray absorption spectroscopy, Raman, X-ray photoelectron spectroscopy, and X-ray diffraction. These analyses have proven the existence of PdIn bimetallic nanoparticles supported on N-doped carbon. In situ DRIFT spectroscopy reveals the advantageous role of indium (In) in regulating Pd activity in alkyne semihydrogenation. Notably, incorporating a soft nucleation step before pyrolysis enhances surface area, porosity, and nitrogen content compared to direct MOF pyrolysis. The optimized material exhibits outstanding catalytic performance with 96% phenylacetylene conversion and 96% selectivity to phenylethylene in the fifth cycle under mild conditions (5 mmol phenylacetylene, 7 mg cat, 5 mL EtOH, R.T., 1 H2 bar).

2.
Front Public Health ; 12: 1250299, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655514

RESUMO

This overview assessed the available body of published peer-reviewed systematic reviews and meta-analyses related to the effects of active exergames compared with active/passive control on physical performance outcomes in older people. The methodological quality and certainty of evidence were assessed using PRISMA, AMSTAR 2, and GRADE. The protocol was registered in PROSPERO (code: CRD42023391694). The main outcomes indicate that 4,477 records, five systematic reviews, and 10 meta-analyses were included. The AMSTAR-2 reported six meta-analyses with high methodological quality, four moderate quality, two systematic reviews with low quality, and three very-low quality. Meta-analysis was performed on balance using the Berg Balance Scale (BBS) and Timed Up-and-Go (TUG) tests, on cardiorespiratory fitness using the 6-min walk test, and on upper and lower limbs muscle strength using the handgrip strength, knee extension, and 30-s chair stand tests. Significant differences in favor of the active exergames groups concerning active/passive groups were reported in BBS (SMD = 0.85; 95% CI = 0.12-1.58; I2 = 96%; p = 0.02), TUG (SMD = 1.44; 95% CI = 0.71-2.16; I2 = 97%; p < 0.0001), and 30-s chair stand test (SMD = 0.79; 95% CI = 0.33-1.25; I2 = 88%; p = 0.0008). However, no significant differences were reported in favor of the active exergames groups in 6-min walk (SMD = 0.93; 95% CI = -0.64 to 2.50; I2 = 95%; p = 0.24), handgrip strength (SMD = 0.67; 95% CI = -0.04 to 1.38; I2 = 84%; p = 0.06), and knee extension tests (SMD = 0.20; 95% CI = -0.05 to 0.44; I2 = 95%; p = 0.12) compared to active/passive control. However, it was impossible to perform a meta-analysis for the variables of walking speed as a fall risk due to the diversity of instruments and the small number of systematic reviews with meta-analysis. In conclusion, interventions utilizing active exergames have shown significant improvements in the static and dynamic balance and lower limb muscle strength of apparently healthy older people, compared to control groups of active/inactive participants, as measured by BBS, TUG, and 30-s chair stand tests. However, no significant differences were found in the 6-min walk, HGS, and knee extension tests. Systematic review registration: PROSPERO, CRD42023391694.


Assuntos
Desempenho Físico Funcional , Equilíbrio Postural , Idoso , Idoso de 80 Anos ou mais , Humanos , Aptidão Cardiorrespiratória/fisiologia , Exercício Físico/fisiologia , Força Muscular/fisiologia , Equilíbrio Postural/fisiologia , Revisões Sistemáticas como Assunto , Jogos de Vídeo , Metanálise como Assunto
3.
Am J Biol Anthropol ; : e24922, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409941

RESUMO

OBJECTIVES: Comparisons between Indigenous peoples over time and within a particular geographic region can shed light on the impact of environmental transitions on the skeleton, including relative bone strength, sexual dimorphism, and age-related changes. Here we compare long bone structural properties of the inhabitants of the late prehistoric-early historic Pecos Pueblo with those of present-day Indigenous individuals from New Mexico. MATERIALS AND METHODS: Femora and tibiae of 126 adults from Pecos Pueblo and 226 present-day adults were included in the study. Cross-sectional diaphyseal properties-areas and second moments of area-were obtained from past studies of the Pecos Pueblo skeletal sample, and from computed tomography scans of recently deceased individuals in the present-day sample. RESULTS: Femora and tibiae from Pecos individuals are stronger relative to body size than those of present-day Indigenous individuals. Present-day individuals are taller but not wider, and this body shape difference affects cross-sectional shape, more strongly proximally. The tibia shows anteroposterior strengthening among Pecos individuals, especially among males. Sexual dimorphism in midshaft bone shape is stronger within the Pecos Pueblo sample. With aging, Pecos individuals show more medullary expansion but also more subperiosteal expansion than present-day individuals, maintaining bone strength despite cortical thinning. DISCUSSION: Higher activity levels, carried out over rough terrain and throughout adult life, likely explain the relatively stronger lower limb bones of the Pecos individuals, as well as their greater subperiosteal expansion with aging. Greater sexual dimorphism in bone structure among Pecos individuals potentially reflects greater gender-based differences in behavioral patterns.

4.
Nutr. clín. diet. hosp ; 44(1): 74-83, Feb. 2024. tab, graf
Artigo em Inglês | IBECS | ID: ibc-231295

RESUMO

Introduction: Physical inactivity is a factor that con-tributes to increased cardiometabolic risk, such as overweightand obesity in schoolchildren.Aim: To associate physical activity habits with morphologi-cal variables (body mass index [BMI], waist circumference[WC], body fat, and fat-free mass), blood pressure, glycemia,handgrip strength (HGS), and countermovement jump (CMJ)in Chilean male schoolchildren. In addition, to compare phys-ically active (PA) schoolchildren to physically inactive (PI)schoolchildren on morphological variables, blood pressure,glycemia, HGS, and CMJ. Material and methods: A cross-sectional study analyzed160 schoolchildren with a mean age of 7.12 ± 4.5 years dis-tributed into PA schoolchildren (n=75) and PI schoolchildren(n=85). A logistic regression was performed to identify theassociation between physical activity habits with factors ofmorphological variables (BMI, WC, body fat, and fat-freemass), blood pressure, glycemia, HGS, and CMJ. In addition,to compare the differences in physical activity habits (physi-cally active vs. physically inactive), a student’s t-test was per-formed for independent samples. Results: Logistic regression showed that physical activityis protective factor against excess body fat of 46% (OR=0.46; 95%CI= 0.22 to 0.95; p= 0.03), hyperglycemia of 25%(OR= 0.25; 95%CI= 0.12 to 0.51; p< 0.0001), high bloodpressure of 31% (OR= 0.31; 95%CI= 0.15 to 0.67; p=0.002), and HGS dominant hand of 40% (OR= 0.40; 95%CI=0.19 to 0.83; p= 0.014). Conclusion: Physical activity protected against excessbody fat, hyperglycemia, hypertension, and decreased HGSin Chilean male schoolchildren. PA schoolchildren exhibitedlower body fat, reduced risk of hyperglycemia and hyper-tension, and improved HGS and CMJ compared to PI school-children.(AU)


Introducción: La inactividad física es un factor que contribuye al aumento del riesgo cardiometabólico, como el sobrepeso y la obesidad en escolares.Objetivo: Asociar los hábitos de actividad física con variables morfológicas (índice de masa corporal [IMC], circunferencia de cintura [CC], grasa corporal y masa libre de grasa), presión arterial, glucemia, fuerza de prensión manual (FPM) y salto con contramovimiento (CMJ) en escolares hombres chilenos. Además, comparar escolares físicamente activos (FA) con escolares físicamente inactivos (FI) en variables morfológicas, presión arterial, glucemia, FPM y CMJ.Material y métodos: Estudio transversal que analizó 160 escolares con una edad media de 7,12 ± 4,5 años distribuidos en escolares FA (n= 75) y escolares FI (n= 85). Se realizó una regresión logística para identificar la asociación entre los hábitos de actividad física con factores de las variables morfológicas (IMC, CC, grasa corporal y masa libre de grasa), presión arterial, glucemia, FPM y CMJ. Además, para comparar las diferencias en los hábitos de actividad física (físicamente activos vs. físicamente inactivos), se realizó la prueba t de Student para muestras independientes.Resultados: La regresión logística mostró que la actividad física es un factor protector contra el exceso de grasa corporal en un 46% (OR= 0,46; IC95%= 0,22 a 0,95; p= 0,03), hiperglucemia en un 25% (OR= 0,25; IC95%= 0,12 a 0,51; p< 0,0001), hipertensión arterial del 31% (OR= 0,31; IC95%= 0,15 a 0,67; p= 0,002), y FPM en mano dominante del 40% (OR= 0,40; IC95%= 0,19 a 0,83; p= 0,014).Conclusión: La actividad física protegió contra el exceso de grasa corporal, la hiperglucemia, la hipertensión arterial y la disminución de FPM en escolares hombres chilenos. Los escolares FA exhibieron menos grasa corporal, menor riesgo de hiperglucemia e hipertensión, y FPM, además de CMJ mejorados en comparación con los escolares FI.(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Estado Nutricional , Nutrição da Criança , Nível de Saúde , Obesidade Infantil , Sobrepeso , Comportamento Sedentário , Pediatria , Ciências da Nutrição , Estudos Transversais
5.
J Sports Med Phys Fitness ; 64(3): 301-310, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38261333

RESUMO

INTRODUCTION: This systematic review aimed to analyze the available body of published peer-reviewed studies on the effects of combat sports compared with active/passive control on cognitive function and electrophysiological markers of brain activity in older people. EVIDENCE ACQUISITION: The studies were searched in Scopus, Web of Science, PubMed, MEDLINE, and PsycINFO databases from deadline to June 2023. The PRISMA, TESTEX, RoB, and GRADE scales assessed the evidence's methodological quality and certainty of evidence. The protocol was registered in PROSPERO (code: CRD42022361695). EVIDENCE SYNTHESIS: After reviewing 3768 studies, seven combat sports interventions (score ≥60% in methodological quality) were selected, composed of 381 older people (63% female), with a mean age of 66 years. In the selected studies, interventions based on judo, karate, and taekwondo were carried out, where it was not possible to verify the benefits of combat sports in cognitive function and electrophysiological markers of brain activity regarding active/passive control groups, although the individual results of the analyzed studies indicate that the practice of combat sports favor selective attention, divided attention, executive function, visual perception, and cognitive processing speed in older people. CONCLUSIONS: The available evidence does not allow a definite recommendation regarding combat sports as an effective cognitive function intervention in older people.


Assuntos
Cognição , Artes Marciais , Idoso , Humanos , Função Executiva , Artes Marciais/fisiologia , Percepção Visual
6.
Front Physiol ; 14: 1270512, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074324

RESUMO

This study aimed to analyze the effect of plyometric training (PT) at different frequencies on jump performance, running sprint speed, and service speed in youth male volleyball players. The participants were randomly assigned to one PT session per week (Experimental Group 1, EG1, n = 15), two PT sessions per week (Experimental Group 2, EG2, n = 14), and a control group (CG, n = 13). The total weekly jumping ranged between 98 and 196 jumps (equalized between, EG1 and, EG2). The assessments performed were squat jump (SJ), countermovement jump (CMJ), CMJ-arms, drop jump (DJ), 5-m sprint, 10-m sprint, and service speed. The intragroup comparisons showed that, EG1 significantly (p < 0.001) improved SJ (Δ = 12.74%; d = 1.30), CMJ (Δ = 11.94%; d = 1.71), CMJ-arms (Δ = 12.02%; d = 1.47), DJ (Δ = 10.93%; d = 1.30), 5-m sprint (Δ = -4.61%; d = 0.29), 10-m sprint (Δ = -3.95%; d = 0.40) and service speed (Δ = 8.17%; d = 1.53). Similarly, EG2 significantly (p˂ 0.001) improved SJ (Δ = 11.52%; d = 1.25), CMJ (Δ = 11.29%; d = 1.38), CMJ-arms (Δ = 11.42%; d = 1.26), DJ (Δ = 13.90%; d = 2.17), 5-m sprint (Δ = -3.85%; d = 0.25), 10-m sprint (Δ = -2.73%; d = 0.25) and service speed (Δ = 6.77%; d = 1.44). The CG significantly (p < 0.05) improved SJ (Δ = 2.68; d = 0.28), CMJ-arms (Δ = 2.30; d = 0.35), 5-m sprint (Δ = -1.27; d = 0.10) and service speed (Δ = 1.42; d = 0.30). Intergroup comparisons revealed significantly greater improvements in all variables (p < 0.001) in, EG1 and, EG2 concerning to CG. However, no significant differences were found between, EG1 and, EG2. A moderate weekly PT volume, distributed in one or two sessions per week, seems equally effective.

7.
J Clin Med ; 12(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068275

RESUMO

This systematic review aimed to assess the available body of published peer-reviewed articles related to the effects of Olympic combat sports (OCS) on cardiorespiratory fitness (CRF) in the non-athlete population. The methodological quality and certainty of evidence were evaluated using PRISMA, TESTEX, RoB, and GRADE scales. The protocol was registered in PROSPERO (code: CRD42023391433). From 4133 records, six randomized controlled trials were included, involving 855 non-athletes (mean age = 27.2 years old). The TESTEX scale reported all studies with a ≥ 60% (moderate-high quality) score. The GRADE scale indicated moderate to low certainty of evidence. It was only possible to perform a meta-analysis on direct methods to maximum oxygen consumption (VO2max). The main results indicated significant differences in favor of OCS compared to active/passive controls in VO2max (SMD = 4.61; 95%CI = 1.46 to 7.76; I2 = 99%; p = 0.004), while the individual results of the studies reported significant improvements in favor of the OCS on the indirect methods of the CRF. OCS improved CRF in a healthy non-athlete population of different ages, specifically showing a significant improvement in VO2max with direct tests, such as cardiopulmonary tests. However, moderate to low certainty of evidence is reported, so no definitive recommendations can be established.

8.
Front Public Health ; 11: 1236402, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37886049

RESUMO

This study, called the TKD and Aging Project, aimed to analyze and compare the effects of an adapted taekwondo program concerning multicomponent training on blood pressure, morphological variables, food consumption frequency, health-related quality of life (HRQoL), physical fitness, handgrip strength, and postural balance in independent older women. A randomized controlled trial study was conducted with parallel groups for 8 weeks (24 sessions of 60 min each), employing a double-blind design and incorporating repeated measures. Twenty-eight older women initially participated in the intervention. Three participants were excluded because they did not participate in the re-assessments. Thus, 14 older women from the adapted taekwondo group (TKD; age: 62.86 ± 2.38 years) and 11 from the multicomponent training group (MCT; age: 63.18 ± 1.94 years) participated in the final analysis. A two-factor mixed analysis of variance (ANOVA) model with repeated measures was performed to measure the time × group effect. The TKD showed significant improvements in the mental health (p = 0.024; ES = 0.91) and general health (p < 0.001; ES = 0.75) dimensions of the HRQoL, as well as in the chair stand (p = 0.001; ES = 1.18), arm curl (p < 0.001; ES = 2.10), 2-min step (p < 0.001; ES = 1.73), and chair sit-and-reach (p = 0.001; ES = 0.91) tests. Additionally, it showed a significant reduction in postural balance for the eyes-closed condition in the center of the pressure area (p = 0.021; ES = 0.89), mean velocity (p = 0.004; ES = 0.79), and mediolateral velocity (p < 0.001; ES = 1.26). However, the MCT showed significant increases in the general health (p = 0.013; ES = 0.95) dimension of the HRQoL and a significant reduction (p = 0.039; ES = 0.28) in the mediolateral velocity of postural balance for the eyes-closed condition. Multiple comparisons showed that the TKD scored significantly higher in the chair stand (p = 0.017; ES = 1.79), arm curl (p = 0.003; ES = 1.77), and 2-min step (p = 0.018; ES = 0.91) tests than the MCT. Compared to multicomponent training, taekwondo improves postural balance and provides better benefits in terms of physical fitness and HRQoL for older women. Therefore, it is possible to recommend it as a safe physical activity strategy, as long as it is well-dosed, since it showed high adherence to intervention in older women.


Assuntos
Terapia por Exercício , Força da Mão , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Terapia por Exercício/métodos , Força da Mão/fisiologia , Qualidade de Vida , Exercício Físico/fisiologia , Aptidão Física/fisiologia
9.
BMC Public Health ; 23(1): 2113, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891589

RESUMO

BACKGROUND: Sarcopenia is a syndrome associated with aging that causes progressive loss of skeletal muscle mass and muscle function. In this pilot study, we compared the effectiveness of elastic band training regarding group-based dance on fat mass, fat-free mass, handgrip strength (HGS; dominant and non-dominant hand), leg strength, timed up-and-go (TUG) and walking speed in older women with sarcopenia. METHODS: This is a randomized controlled trial, single-blind, repeated measures of parallel groups (elastic band group: EBG, n = 21; group-based dance: GBD, n = 19), and a quantitative methodology. Three 60-minute sessions per week for 12 weeks were dedicated to the interventions with pre- and post-assessments. A two-factor mixed analysis of variance (ANOVA) model with repeated measures was performed to measure the group×time effect. RESULTS: A significant interaction revealed for fat-free mass (F1,16= 18.91; p < 0.001; EBG + 10.9% vs. GBD - 1.97%), HGS dominant hand (F1,16= 7.44; p = 0.014; EBG + 10.9% vs. GBD + 0.59%), HGS non-dominant hand (F1,16= 6.41; p = 0.022; EBG + 10.21% vs. GBD + 3.80%), leg strength (F1,16= 17.98; p < 0.001; EBG + 9.1% vs. GBD + 3.83%), TUG (F1,16= 7.52; p = 0.014; EBG - 14.7% vs. GBD - 1.0%) and walking speed (F1,16 = 6.40; p = 0.019; EBG - 7.6% vs. GBD - 4.35%) in favor of EBG. CONCLUSION: Elastic band training produces significantly greater responses on physical-functional performance regarding group-based dance in older women with sarcopenia. On the other hand, the EBG revealed a significant improvement in fat-free mass and upper and lower limb muscle strength, as well as a significant decrease time in TUG, and walking speed. Elastic band exercise is a safe, easy, affordable, and effective physical activity strategy, according to the findings.


Assuntos
Treinamento Resistido , Sarcopenia , Humanos , Feminino , Idoso , Sarcopenia/terapia , Sarcopenia/patologia , Força Muscular/fisiologia , Força da Mão/fisiologia , Projetos Piloto , Método Simples-Cego , Desempenho Físico Funcional , Músculo Esquelético
10.
Children (Basel) ; 10(9)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37761491

RESUMO

This study protocol aims to analyze and compare the effects of combined movement and storytelling intervention (CMSI) on fundamental motor skills (locomotor skills and object control), language development (language comprehension, language expression, vocabulary and language description), and physical activity levels (light intensity, moderate-to-vigorous intensity and sedentary time) in children aged 3 to 6 years. The sample will consist of 144 children from 12 class groups, randomly assigned to 3 experimental groups (n = 72 children) and 3 control groups (n = 72 children), belonging to 4 class groups of upper-middle-level classes (2 experimental and 2 control; 3 to 4 years), 4 transition level 1 classes (2 experimental and 2 control; 4 to 5 years) and 4 transition level 2 classes (2 experimental and 2 control; 5 to 6 years). The experimental groups will perform CMSI for 3 sessions per week (40 min per session) over 12 weeks (using one motor story per week), while the control groups will not receive any treatment. The main outcome will provide information about fundamental motor skills, language development, and physical activity levels. Our hypothesis indicates that CMSI has the potential to generate significant increases in selected assessments. If this intervention proves to be beneficial, it could contribute to preschool and school curricula.

11.
Sci Rep ; 13(1): 15204, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709850

RESUMO

Chronic positive energy balance has surged among societies worldwide due to increasing dietary energy intake and decreasing physical activity, a phenomenon called the energy balance transition. Here, we investigate the effects of this transition on bone mass and strength. We focus on the Indigenous peoples of New Mexico in the United States, a rare case of a group for which data can be compared between individuals living before and after the start of the transition. We show that since the transition began, bone strength in the leg has markedly decreased, even though bone mass has apparently increased. Decreased bone strength, coupled with a high prevalence of obesity, has resulted in many people today having weaker bones that must sustain excessively heavy loads, potentially heightening their risk of a bone fracture. These findings may provide insight into more widespread upward trends in bone fragility and fracture risk among societies undergoing the energy balance transition.


Assuntos
Fraturas Ósseas , Humanos , Densidade Óssea , Ingestão de Energia , Exercício Físico , Fraturas Ósseas/epidemiologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-37681828

RESUMO

This study aimed to associate physical activity habits with cardiometabolic variables (blood pressure, fasting glucose, HDL cholesterol, and triglycerides), body composition (body fat percentage and fat-free mass), and physical performance (handgrip strength (HGS), timed up-and-go (TUG), and walking speed) in Chilean older women. An analytical cross-sectional study analyzed 179 older women with a mean age of 75.4 years distributed into physically inactive (PI) older women (n = 74) and physically active (PA) older women (n = 105). A logistic regression showed that PI older women presented an increased risk of hyperglycemia (OR = 4.70; p = 0.000), high blood pressure (OR = 3.83; p = 0.000), low HDL cholesterol levels (OR = 2.13; p = 0.03), hypertriglyceridemia (OR = 2.54; p = 0.01), excess body fat percentage (OR = 4.33; p = 0.000), low fat-free mass (OR = 2.22; p = 0.02), low HGS in their dominant hand (OR = 3.37; p = 0.001) and non-dominant hand (OR = 3.60; p = 0.0001), and poor performance in TUG (OR = 5.60; p = 0.000) and walking speed (OR = 5.52; p = 0.000). In conclusion, physical inactivity was associated with increased cardiometabolic risk, excess body fat percentage, lower fat-free mass, and poorer physical performance in Chilean older women. At the same time, PA older women showed a lower cardiometabolic risk, better body composition, and better physical performance than PI older women.


Assuntos
Força da Mão , Hipertensão , Humanos , Feminino , Idoso , Chile/epidemiologia , HDL-Colesterol , Estudos Transversais , Composição Corporal , Exercício Físico , Hábitos , Desempenho Físico Funcional
15.
Front Physiol ; 14: 1127669, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875040

RESUMO

This study aims to compare the effects of standard warm-up versus warm-up using stretching exercises on the physical performance of male youth soccer players. Eighty-five male soccer players (age: 10.3 ± 4.3 years; body mass index: 19.8 ± 4.3 kg/m2) were assessed for countermovement jump height (CMJ, cm), 10 m, 20 m and 30 m running sprint speed (s) and ball kicking speed (km/h) for the dominant and non-dominant leg under five (randomized) warm-up conditions. Using 72 h of recovery between conditions, the participants completed a control condition (CC) and four experimental conditions, including static stretching (SSC), dynamic stretching (DSC), ballistic stretching (BSC), and proprioceptive neuromuscular facilitation (PNFC) exercises. All warm-up conditions had a duration of 10 minutes. The main results indicate that no significant differences (p > 0.05) were found between warm-up conditions compared to CC in CMJ (CC = 28.1 ± 4.9; SSC = 28.4 ± 4.9; DSC = 30.9 ± 4.8; BSC = 30.9 ± 5.2; PNFC = 28.4 ± 5.0), 10 m sprint (CC = 2.42 ± 0.4; SSC = 2.50 ± 0.4; DSC = 2.30 ± 0.3; BSC = 2.27 ± 0.3; PNFC = 2.53 ± 0.4), 20 m sprint (CC = 5.42 ± 0.9; SSC = 5.59 ± 0.9; DSC = 5.37 ± 0.9; BSC = 5.40 ± 0.9; PNFC = 5.44 ± 0.9), 30 m sprint (CC = 8.05 ± 1.3; SSC = 8.27 ± 1.3; DSC = 8.01 ± 1.3; BSC = 8.00 ± 1.3; PNFC = 8.12 ± 1.3), ball kicking speed for dominant (CC = 56.2 ± 4.9; SSC = 55.3 ± 5.2; DSC = 56.9 ± 5.8; BSC = 57.3 ± 5.8; PNFC = 55.7 ± 5.2) and non-dominant leg (CC = 52.8 ± 3.4; SSC = 51.8 ± 4.6; DSC = 53.5 ± 5.4; BSC = 53.6 ± 4.9; PNFC = 52.5 ± 4.0). In conclusion, compared to standard warm-up, stretching-based warm-up exerts no effect on male youth soccer players jump height, sprint speed and ball kicking speed.

17.
Dalton Trans ; 51(46): 17567-17578, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36331010

RESUMO

Alcohol oxidation is one of the most important industrial organic reactions. Traditionally, the best-suited catalysts are Pd, Pt and Au supported nanoparticles. The research community has recently started developing strategies for synthesizing carbon-supported Pd/Au bimetallic nanoparticles (NPs), leading to higher activities and selectivities. However, the metallic active species in these catalysts are usually generated using sodium borohydride (NaBH4), which is not synthetically easy to reproduce. In fact, minor modifications in pH, concentration and/or other parameters have a prominent effect on the nature of the promoted material. In this work, a robust process involving dihydrogen flow (H2) at 200 °C as a reducing agent for synthesizing Pd/Au supported bimetallic materials was considered an alternative to the common pathway. The physicochemical properties of the materials derived from different reducing reagents and of varying composition ranges were studied using HR-TEM, XRD, CO chemisorption, and XPS. Their stability and activity were also tested for benzyl alcohol oxidation to benzaldehyde under mild reaction conditions (60 °C, water as the solvent, and PO2 = 1.5 bar). Notably, a catalyst from the hydrogen reduction process with a metal composition of 0.8%Pd-0.2%Au/C consisting of bimetallic clusters (≈1.5 nm) proved to be the best material (C = 94%, S = 99%). Catalytic performances were strongly correlated with structural properties, such as nanoparticle size and distribution, which, in turn, were affected by the reduction step and the metal composition range. Finally, the influence of oxidants on benzyl alcohol oxidation has also been studied, along with the first approach for the tandem in situ formation of H2O2 coupled with alcohol oxidation.

18.
Artigo em Inglês | MEDLINE | ID: mdl-36360685

RESUMO

This study aimed to associate morphological variables and physical fitness with health-related quality of life (HRQoL) in physically active older people. A cross-sectional study was carried out that evaluated 470 older people (89.57% female) with a mean age of 70.13 ± 6.57 years, residing in two regions of Chile. Morphological variables (body weight, bipedal height, waist circumference, body mass index, and waist to height ratio), physical fitness through the Senior Fitness Test protocol, and HRQoL using the SF-36 questionnaire were obtained. Logistic regression analysis was used to identify risk factors between morphological variables and physical fitness associated with HRQoL. The main results indicated that overweight (OR = 1.52; p = 0.034), a waist circumference with risk (OR = 1.56; p = 0.021), poor performance in the back scratch tests (OR = 1.02; p = 0.008) and timed up-and-go (OR = 1.19; p = 0.040) increased the probability of having a low general HRQoL. Also, the low performance of chair stand and arm curl tests was associated with poor physical and social dimensions of HRQoL (p < 0.05). In conclusion, a low HRQoL in physically active older people is associated with both morphological and physical fitness factors.


Assuntos
Aptidão Física , Qualidade de Vida , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Índice de Massa Corporal , Circunferência da Cintura
19.
Artigo em Inglês | MEDLINE | ID: mdl-36293916

RESUMO

This study aims to analyze the effect of different types of warm-ups on handgrip strength (HGS) in physically inactive older females. Secondarily, it aims to compare HGS according to their baseline nutritional status. A randomized crossover trial study was conducted with 44 physically inactive older females distributed into normal weight (n = 12, BMI = 23.9 ± 3.2 kg/m2), overweight (n =16, BMI = 27 ± 4.7 kg/m2) and obese (n = 16, BMI = 31.6 ± 5.3 kg/m2), who participated in three warm-up conditions (static stretching condition, SSC; elastic band condition, EBC; and therapeutic compression ball condition, TCBC) and one control condition (CC, no warm-up). All participants performed the four randomized conditions with recovery within 72 h. A significant decrease (p < 0.05) in HGS for the dominant and non-dominant hands was observed when comparing SSC vs. CC. In contrast, comparing the warm-up conditions according to the baseline nutritional status, statistically significant differences (p < 0.05) were only reported in the obese group in the dominant and non-dominant hand in favor of CC concerning SSC. In conclusion, warm-up with static flexibility led to a decrease in HGS in physically inactive older females. Only the obese group exhibited this result when analyzed by nutritional status.


Assuntos
Força da Mão , Estado Nutricional , Humanos , Feminino , Chile , Sobrepeso/epidemiologia , Obesidade/epidemiologia
20.
Chem Commun (Camb) ; 58(85): 11917-11920, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36196958

RESUMO

The photoluminescent eight-coordinate zirconium complex Zr(HPMPH)4 supported by four monoanionic 2-(2'-pyridine)pyrrolide ligands was synthesized. This molecule shows dual emission via fluorescence and phosphorescence with an overall quantum efficiency of 4% at room temperature in solution. The phosphorescence lifetime is dependent on concentration, indicating excimer formation at higher concentrations, and reaches almost 800 µs at high dilution.


Assuntos
Piridinas , Zircônio , Ligantes , Fluorescência
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