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To examine the prevalence of active commuting to school (ACS) in 4 to 6 year old children and individual and social factors associated with it. Cross-sectional study including 1,159 children from Cuenca and Ciudad Real (Castilla-La Mancha, Spain). ACS, population area, and socioeconomic status (SES) were self-reported by parents. Body mass index and cardiorespiratory fitness (CRF) were measured using standard procedures. Binary logistic regression models were used to assess the strength of association between the mode of commuting (ACS/no-ACS) and individual (weight status and CRF) and social (population area and SES) factors. Forty-six percent of the children ACS. The probability of ACS was greater in boys and girls from families of low/medium-low SES and in girls who lived in urban areas. ACS was not associated with weight status and CRF. Effective interventions need to be promoted, especially in children from families of high SES and those living in rural areas.
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Individualidade , Instituições Acadêmicas , Fatores Sociais , Meios de Transporte/estatística & dados numéricos , Peso Corporal , Aptidão Cardiorrespiratória , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Classe Social , EspanhaRESUMO
In recent years, interest in the relation between maternal physical activity during pregnancy and children's neurocognitive development has been growing. Several observational studies and clinical trials have analysed this relation and they differ in the findings, especially for children's language-related skills and IQ. Physical activity assessment, amount of physical activity and the test used for measuring children's cognition could affect this relation, as well as other factors that should be considered. This article will review the evidence on the effects of physical activity during pregnancy on children's different cognitive domains. TWEETABLE ABSTRACT: Leisure physical during pregnancy positively affects offspring's general intelligence and language skills.
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Desenvolvimento Infantil , Cognição , Exercício Físico , Atividades de Lazer , Efeitos Tardios da Exposição Pré-Natal , Criança , Feminino , Humanos , Inteligência , GravidezRESUMO
The aim of this study was to analyze the mediation role of cardiorespiratory fitness and waist circumference in the association between muscular strength and cardiometabolic risk. A cross-sectional study involved first-year college students (n = 370) from a Spanish public university was performed. We measured weight, height, waist circumference, blood pressure, biochemical variables, maximum handgrip strength assessment, and cardiorespiratory fitness. We calculated handgrip dynamometry/weight and a previously validated cardiometabolic risk index. Analysis of covariance models was conducted to test differences in cardiometabolic risk values across muscular strength, cardiorespiratory fitness, and waist circumference categories, controlling for confounders. Hayes' PROCESS macro was used for the multiple mediation analysis. The relationship between muscular strength and cardiometabolic risk did not remain significant (c' = 1.76 [1.4]; P > .05) in a multiple serial bootstrapped mediation model including cardiorespiratory fitness and waist circumference as mediators when controlling for age and sex. According to the indirect effect, the significant paths in the model mediating this relationship between muscular strength and cardiometabolic risk index were as follows: muscular strength â waist circumference â cardiometabolic risk index (-4.899; 95% CI: -6.690; -3.450) and muscular strength â cardiorespiratory fitness â waist circumference â cardiometabolic risk index (-0.720; 95% CI: -1.316; -0.360). Both cardiorespiratory fitness and waist circumference mediate the association between muscular strength and cardiometabolic risk in young adults. Thus, our results place cardiorespiratory fitness and waist circumference as the main targets of physical activity programmes aimed at preventing cardiometabolic diseases.
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Aptidão Cardiorrespiratória , Força da Mão , Circunferência da Cintura , Adolescente , Pressão Sanguínea , Peso Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The specific role of different strength measures on mortality risk needs to be clarified to gain a better understanding of the clinical importance of different muscle groups, as well as to inform intervention protocols in relation to reducing early mortality. The aim of the systematic review and meta-analysis was to determine the relationship between muscular strength and risk of cancer mortality. Eligible cohort studies were those that examined the association between muscular strength, as assessed using validated tests, and cancer mortality in healthy youth and adults. The hazard ratio (HR) estimates obtained were pooled using random effects meta-analysis models. The outcome was cancer mortality assessed using the HR (Cox proportional hazards model). Eleven prospective studies with 1 309 413 participants were included, and 9787 cancer-specific deaths were reported. Overall, greater handgrip (HR = 0.97, 95% CI, 0.92-1.02; P = .055; I2 = 18.9%) and knee extension strength (HR = 0.98, 95% CI, 0.95-1.00; P = .051; I2 = 60.6%) were barely significant associated with reduced risk of cancer mortality. Our study suggests that higher level of muscular strength is not statistically associated with lower risk of cancer mortality.
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Força da Mão , Neoplasias/mortalidade , Humanos , Modelos de Riscos ProporcionaisRESUMO
We reconstruct the 3-D microstructure of centimetre-sized olivine crystals in rocks from the Almirez ultramafic massif (SE Spain) using combined X-ray micro computed tomography (µ-CT) and electron backscatter diffraction (EBSD). The semidestructive sample treatment involves geographically oriented drill pressing of rocks and preparation of oriented thin sections for EBSD from the µ-CT scanned cores. The µ-CT results show that the mean intercept length (MIL) analyses provide reliable information on the shape preferred orientation (SPO) of texturally different olivine groups. We show that statistical interpretation of crystal preferred orientation (CPO) and SPO of olivine becomes feasible because the highest densities of the distribution of main olivine crystal axes from EBSD are aligned with the three axes of the 3-D ellipsoid calculated from the MIL analyses from µ-CT. From EBSD data we distinguish multiple CPO groups and by locating the thin sections within the µ-CT volume, we assign SPO to the corresponding olivine crystal aggregates, which confirm the results of statistical comparison. We demonstrate that the limitations of both methods (i.e. no crystal orientation data in µ-CT and no spatial information in EBSD) can be overcome, and the 3-D orientation of the crystallographic axes of olivines from different orientation groups can be successfully correlated with the crystal shapes of representative olivine grains. Through this approach one can establish the link among geological structures, macrostructure, fabric and 3-D SPO-CPO relationship at the hand specimen scale even in complex, coarse-grained geomaterials.
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Our purpose in this study was to investigate efficient and sustainable combinations of exercise and diet-induced weight loss (DIET), in order to combat obesity in metabolic syndrome (MetS) patients. We examined the impact of aerobic interval training (AIT), followed by or concurrent to a DIET on MetS components. 36 MetS patients (54±9 years old; 33±4 BMI; 27 males and 9 females) underwent 16 weeks of AIT followed by another 16 weeks without exercise from the fall of 2013 to the spring of 2014. Participants were randomized to AIT without DIET (E CON, n=12), AIT followed by DIET (E-then-D, n=12) or AIT concurrent with DIET (E+D, n=12) groups. Body weight decreased below E CON similarly in the E-then-D and E+D groups (~5%). Training improved blood pressure and cardiorespiratory fitness (VO2peak) in all groups with no additional effect of concurrent weight loss. However, E+D improved insulin sensitivity (HOMA) and lowered plasma triglycerides and blood cholesterol below E CON and E-then-D (all P<0.05). Weight loss in E-then-D in the 16 weeks without exercise lowered HOMA to the E+D levels and maintained blood pressure at trained levels. Our data suggest that a new lifestyle combination consisting of aerobic interval training followed by weight loss diet is similar, or even more effective on improving metabolic syndrome factors than concurrent exercise plus diet.
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Dieta Redutora , Terapia por Exercício , Síndrome Metabólica/terapia , Redução de Peso , Adulto , Pressão Sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/terapia , Consumo de Oxigênio , Aptidão FísicaRESUMO
BACKGROUND: Sleep disorders in schoolchildren are a common problem worldwide, and when are not adequately diagnosed and treated, their negative impact on daytime functioning may be significant. The aim of this study was to evaluate the psychometric properties of the Spanish version of the Children's Sleep Habits Questionnaire (CSHQ). METHODS: Participants were 286 school-aged children from a community-based sample, aged 4 to 7 years. The sleep behaviour was evaluated using the CSHQ and actigraphy (ActiSleep monitor). The CSHQ was adapted to the Spanish language. The internal consistency of the questionnaire and the test-retest reliability between scores at baseline and three-weeks-later were estimated. Associations between CSHQ items and accelerometer sleep quality indicators were used as indicators of concurrent validity. RESULTS: Cronbach's alpha coefficients for the subscales ranged from 0.60 to 0.81, and 0.81 for the full scale; the intraclass correlation coefficients ranged from 0.56 to 0.81. A moderate correlation was observed in sleep latency and awakenings measurements using both parents' reported sleep habits (CSHQ-SP) and sleep quality indicators (ActiSleep). CONCLUSIONS: The CSHQ-SP has demonstrated adequate psychometric properties, and it serves as a useful instrument for clinical and research setting.
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Higiene do Sono , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Actigrafia/métodos , Criança , Comportamento Infantil , Pré-Escolar , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Espanha , Inquéritos e QuestionáriosRESUMO
BACKGROUND: It is commonly accepted that pregnancy-related physiological changes (circulatory, respiratory, and locomotor) negatively influence the daily physical activity of pregnant women. OBJECTIVES: The aim of this study is to conduct a meta-analysis of randomised controlled trials (RCTs) for assessing the effectiveness of physical exercise interventions during pregnancy to prevent gestational diabetes mellitus and excessive maternal weight gain. SEARCH STRATEGY: Keywords were used to conduct a computerised search in six databases: Cochrane Library Plus, Science Direct, EMBASE, PubMed, Web of Science, and ClinicalTrials.gov. SELECTION CRITERIA: Healthy pregnant women who were sedentary or had low levels of physical activity were selected for RCTs that included an exercise programme. DATA COLLECTION AND ANALYSIS: Two independent reviewers extracted data and assessed the quality of the included studies. Of 4225 articles retrieved, 13 RCTs (2873 pregnant women) met the inclusion criteria. Pooled relative risk (RR) or weighted mean differences (WMDs) (depending on the outcome measure) were calculated using a random-effects model. MAIN RESULTS: Overall, physical exercise programmes during pregnancy decreased the risk of gestational diabetes mellitus (RR = 0.69; P = 0.009), particularly when the exercise programme was performed throughout pregnancy (RR = 0.64; P = 0.038). Furthermore, decreases were also observed in maternal weight (WMD = -1.14 kg; 95% CI -1.50 to -0.78; P < 0.001). No serious adverse effects were reported. CONCLUSION: Structured moderate physical exercise programmes during pregnancy decrease the risk of gestational diabetes mellitus and diminish maternal weight gain, and seem to be safe for the mother and the neonate; however, further studies are needed to establish recommendations.
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Diabetes Gestacional/prevenção & controle , Exercício Físico , Aumento de Peso , Adulto , Prática Clínica Baseada em Evidências , Feminino , Humanos , Gravidez , Medicina Preventiva/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
We aimed to examine (a) the construct validity and reliability of the International Fitness Scale (IFIS) in children; and (b) the association of both self-reported and measured fitness with cardiometabolic risk. Cross-sectional study in 1145 Spanish children (9-12 years). We measured body fat, waist circumference, blood pressure, lipids, insulin, and fitness level (reported and measured). A validated cardiometabolic syndrome index was used. An age- and sex-matched sample of 245 children originally not included in the study sample fulfilled IFIS twice for reliability purposes. IFIS was able to correctly classify children according to their measured fitness levels (analysis of covariance, adjusted for sex and age was used). Test-retest reliability of IFIS items was also good, i.e., average weighted Kappa = 0.70. Our data also suggest that both measured and reported cardiorespiratory, and speed and agility fitness were associated with cardiometabolic risk factors, such as adiposity and a cardiometabolic syndrome risk score. The associations for muscular fitness (both reported and measured) differed depending on how it was expressed (i.e., absolute vs relative terms). Our findings suggest that self-reported fitness, as assessed by IFIS, is a valid, reliable, and health-related measure, and it can be a good alternative at population level when physical fitness cannot be measured.
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Aptidão Física/fisiologia , Autorrelato , Adiposidade , Pressão Sanguínea , Criança , Estudos Transversais , Teste de Esforço , Força da Mão/fisiologia , Humanos , Insulina/sangue , Lipídeos/sangue , Reprodutibilidade dos Testes , Medição de Risco , Corrida/fisiologia , Espanha , Circunferência da CinturaRESUMO
OBJECTIVE: The aim of this systematic review and meta-analysis was to examine the evidence for the effectiveness of exercise interventions on attention deficit hyperactivity disorder (ADHD)-related symptoms such as inattention, hyperactivity/impulsivity, anxiety and cognitive functions in children and adolescents. METHOD: Five databases covering the period up to November 2014 (PubMed, Scopus, EMBASE, EBSCO [E-journal, CINAHL, SportDiscus] and The Cochrane Library) were searched. Methodological quality was assessed using the Cochrane tool of bias. Standardized mean differences (SMD) and 95% confidence intervals were calculated, and the heterogeneity of the studies was estimated using Cochran's Q-statistic. RESULTS: Eight randomized controlled trials (n = 249) satisfied the inclusion criteria. The studies were grouped according to the intervention programme: aerobic and yoga exercise. The meta-analysis suggests that aerobic exercise had a moderate to large effect on core symptoms such as attention (SMD = 0.84), hyperactivity (SMD = 0.56) and impulsivity (SMD = 0.56) and related symptoms such as anxiety (SMD = 0.66), executive function (SMD = 0.58) and social disorders (SMD = 0.59) in children with ADHD. Yoga exercise suggests an improvement in the core symptoms of ADHD. CONCLUSIONS: The main cumulative evidence indicates that short-term aerobic exercise, based on several aerobic intervention formats, seems to be effective for mitigating symptoms such as attention, hyperactivity, impulsivity, anxiety, executive function and social disorders in children with ADHD.
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Transtorno do Deficit de Atenção com Hiperatividade/reabilitação , Terapia por Exercício/métodos , Exercício Físico , Criança , Humanos , Cooperação do Paciente , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Sensibilidade e Especificidade , YogaRESUMO
BACKGROUND AND AIMS: Exercise training can improve health of patients with metabolic syndrome (MetS). However, which MetS factors are most responsive to exercise training remains unclear. We studied the time-course of changes in MetS factors in response to training and detraining. METHODS AND RESULTS: Forty eight MetS patients (52 ± 8.8 yrs old; 33 ± 4 BMI) underwent 4 months (3 days/week) of supervised aerobic interval training (AIT) program. After 1 month of training, there were progressive increases in high density lipoprotein cholesterol (HDL-c) and reductions in waist circumference and blood pressure (12 ± 3, -3.9 ± 0.4, and -12 ± 1%, respectively after 4 months; all P < 0.05). However, fasting plasma concentration of triglycerides and glucose were not reduced by training. Insulin sensitivity (HOMA), cardiorespiratory fitness (VO2peak) and exercise maximal fat oxidation (FOMAx) also progressively improved with training (-17 ± 5; 21 ± 2 and 31 ± 8%, respectively, after 4 months; all P < 0.05). Vastus lateralis samples from seven subjects revealed that mitochondrial O2 flux was markedly increased with training (71 ± 11%) due to increased mitochondrial content. After 1 month of detraining, the training-induced improvements in waist circumference and blood pressure were maintained. HDL-c and VO2peak returned to the values found after 1-2 months of training while HOMA and FOMAx returned to pre-training values. CONCLUSIONS: The health related variables most responsive to aerobic interval training in MetS patients are waist circumference, blood pressure and the muscle and systemic adaptations to consume oxygen and fat. However, the latter reverse with detraining while blood pressure and waist circumference are persistent to one month of detraining.
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Exercício Físico/fisiologia , Síndrome Metabólica/terapia , Adaptação Fisiológica , Adulto , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , HDL-Colesterol/sangue , Dieta , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Fatores de Tempo , Triglicerídeos/sangue , Circunferência da CinturaRESUMO
PURPOSE: The objective of this study was to determine the independent relationships of trunk fat, leg fat and arm fat to cardiovascular (CVD) risk factors, after controlling for relevant confounders such as fat mass index, cardiorespiratory fitness and objectively measured physical activity. METHODS: This is a cross-sectional study involving 683 university students, aged 18-30 years. Total and regional body fat distribution was measured using dual-energy X-ray absorptiometry. The associations of trunk, leg and arm fat with CVD risk factors (triglycerides-TG-, high-density lipoprotein cholesterol-HDL-c-, TG/HDL-c ratio, HOMA(IR), mean arterial pressure, C-reactive protein) were examined using regression linear models, controlling for age, sex, fat mass index [total body fat(kg)/height(m(2))], maximal oxygen consumption and physical activity by accelerometer. RESULTS: After controlling for fat mass index, and other confounders, higher levels of trunk fat were found to be associated with a poorer lipid profile, while higher levels of leg fat were found to be associated with a better lipid profile. We did not find any association between arm fat and lipid profile after controlling for total fatness and other confounders. Neither trunk, leg or arm fat was found to be related to insulin resistance, blood pressure or inflammation markers. CONCLUSIONS: Our data suggest that the region where fat is accumulated might have a differential effect on lipid profile: trunk fat has an adverse effect, leg fat has a protective effect, and arm fat has no effect. The differences observed between upper- and lower-body peripheral fat depots should be further explored.
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Braço , Distribuição da Gordura Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Perna (Membro) , Triglicerídeos/sangue , Absorciometria de Fóton , Adolescente , Adulto , Antropometria , Pressão Arterial , Proteína C-Reativa , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Estudos Transversais , Feminino , Humanos , Resistência à Insulina , Masculino , Atividade Motora , Fatores de Risco , Adulto JovemRESUMO
We report experimental results for the ionization and fragmentation of weakly bound van der Waals clusters of n C60 molecules following collisions with Ar(2+), He(2+), and Xe(20+) at laboratory kinetic energies of 13 keV, 22.5 keV, and 300 keV, respectively. Intact singly charged C60 monomers are the dominant reaction products in all three cases and this is accounted for by means of Monte Carlo calculations of energy transfer processes and a simple Arrhenius-type [C60]n(+) â C60(+)+(n-1)C60 evaporation model. Excitation energies in the range of only ~0.7 eV per C60 molecule in a [C60]13(+) cluster are sufficient for complete evaporation and such low energies correspond to ion trajectories far outside the clusters. Still we observe singly and even doubly charged intact cluster ions which stem from even more distant collisions. For penetrating collisions the clusters become multiply charged and some of the individual molecules may be promptly fragmented in direct knock-out processes leading to efficient formations of new covalent systems. For Ar(2+) and He(2+) collisions, we observe very efficient C119(+) and C118(+) formation and molecular dynamics simulations suggest that they are covalent dumb-bell systems due to bonding between C59(+) or C58(+) and C60 during cluster fragmentation. In the Ar(2+) case, it is possible to form even smaller C120-2m(+) molecules (m = 2-7), while no molecular fusion reactions are observed for the present Xe(20+) collisions.
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We aimed to (a) examine the validity and reliability of the International FItness Scale (IFIS) in Spanish young adults and (b) compare the capacity of self-reported vs measured fitness to predict cardiovascular disease (CVD) risk. The study comprised 276 participants (18-30 years). Fitness level (overall and specific components) was both self-reported (IFIS) and measured using standard fitness tests. Total and trunk fat was assessed by dual-energy X-ray absorptiometry. We computed a previously validated metabolic syndrome score. A separate sample of 181 of same age and characteristics fulfilled IFIS twice for reliability purposes. The results of the present study support the validity and reliability of self-reported fitness, as measured by IFIS, in Spanish young adults. Our data also suggest that not only measured cardiorespiratory fitness but also self-reported cardiorespiratory fitness predicts CVD risk, as assessed by adiposity and metabolic syndrome indicators. The associations for muscular fitness (both reported and measured) differed depending on how it was expressed (i.e., absolute vs relative terms). Self-reported fitness, as assessed by IFIS, can be a good alternative when physical fitness cannot be measured in large surveys.
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Doenças Cardiovasculares/diagnóstico , Teste de Esforço , Aptidão Física , Medição de Risco/métodos , Autorrelato , Gordura Abdominal/diagnóstico por imagem , Absorciometria de Fóton , Adiposidade , Adolescente , Adulto , Estudos Transversais , Feminino , Força da Mão , Humanos , Masculino , Força Muscular , Reprodutibilidade dos Testes , Inquéritos e Questionários , Adulto JovemRESUMO
OBJECTIVES: To assess the cross-sectional and longitudinal associations between nut consumption and depression in two cohorts of older adults. DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS: The first cohort (Seniors-ENRICA-I or SE-I) included a representative sample of Spanish noninstitutionalized adults aged ≥65 years interviewed in 2010 and 2013. The second cohort (SE-II) included individuals from the Madrid region, Spain, aged ≥65 years interviewed in 2017 and in 2019. Nut consumption was estimated with a validated computer-based diet history. Depression was defined as self-reported physician-diagnosed depression or the use of antidepressants. Logistic regression models were adjusted for the main confounders. The DerSimonian and Laird random-effect method was used to meta-analyze the results from both studies. A participant-level pooled analysis was conducted to examine the robustness of our analyses. RESULTS: The SE-I included 2278 individuals (233 prevalent cases) in the cross-sectional analysis and 1534 (108 incident cases) in the longitudinal analysis; the corresponding figures for SE-II were 2726 (407 prevalent cases) and 1566 (74 incident cases). In the meta-analysis of cross-sectional results from the two studies, compared to consuming <1 serving (30 g) of nuts/week, the odds ratio (95% confidence interval) for depression was 0.90 (0.64, 1.16) for consuming 1 to <3 servings/week and 0.92 (0.70, 1.13) for consuming ≥3 servings/week; the corresponding figures for the longitudinal results were 0.90 (0.41, 1.38) and 0.66 (0.35, 0.97). CONCLUSION: Nut consumption was associated with a lower risk of depression in a pooled longitudinal analysis using data from two cohorts of older adults. Nuts should be recommended as part of a healthy diet in older adults.
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Depressão , Nozes , Humanos , Idoso , Estudos Transversais , Depressão/epidemiologia , Comportamento Alimentar , Dieta Saudável , DietaRESUMO
BACKGROUND AND OBJECTIVES: Prehypertension is a new category of blood pressure and is considered a cardiovascular risk factor. This study has aimed to estimate the prevalence of prehypertension and the association between prehypertension and other vascular risk factors in young adults. MATERIAL AND METHODS: First year university students from all areas of study in the University of Cuenca were invited to participate. Prehypertension was defined as systolic blood pressure between 120-139 mmHg and/or diastolic blood pressure between 80-89 mmHg. Anthropometric, lipid and metabolic variables were measures. The presence of metabolic syndrome was evaluated and quantified based on the sum of the standardized scores of the waist circumference, the triglyceride/c-HDL ratio, mean blood pressure and R-HOMA (Index of insulin resistance to glucose lowering effect). RESULTS: A total of 545 university students were included in the analysis (mean age 20.36±3.9 years, 74.7% women). Prehypertension prevalence was 24% (95% CI: 21-27%), (56.5% in men and 13% in women). The condition of prehypertension was directly associated to the body mass index (OR: 1.194; 95% CI: 1.124-1.311), insulin resistance (R-HOMA, OR: 2.638; 95% CI: 1.263-4.926) and to the index or quantification of the severity of the metabolic syndrome (OR: 4-868; 95% CI: 3-846-8-328). On the other hand, HDL-c showed an inverse relationship with prehypertension (OR: 0.981; 95% CI: 0.957-0.993). CONCLUSIONS: One out of every four young adults presents prehypertension. This condition is associated to well-established vascular risk factors.
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Pré-Hipertensão/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Adulto JovemRESUMO
In this paper, we present a newly developed crossed beam experimental setup that utilizes the velocity map imaging (VMI) technique to simultaneously measure both the kinetic energy and emission angle of electrons emitted from atoms or molecules upon ion collision. The projectile ion beam with keV to MeV kinetic energy orthogonally crosses the neutral target beam produced by an effusion cell. The emitted electrons are extracted and analyzed by a multi-electrode VMI spectrometer. By monitoring the target density, the projectile ion beam intensity, and the beams' overlap, we are able to measure absolute differential cross sections for collision-induced electron emission from molecules. The characterization of the setup and the methodology will be presented as well as first results for electron emission from uracil upon 0.98 MeV/u 12C4+ collision.
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ElétronsRESUMO
Experiments on neutral gas-phase nucleosides are often complicated by thermal lability. Previous mass spectrometry studies of nucleosides have identified enhanced relative production of nucleobase ions (e.g. uracil+ from uridine) as a function of desorption temperature to be the critical indicator of thermal decomposition. On this basis, the present multi-photon ionization (MPI) experiments demonstrate that laser-based thermal desorption is effective for producing uridine, 5-methyluridine, and 2'-deoxyuridine targets without thermal decomposition. Our experiments also revealed one notable thermal dependence: the relative production of the sugar ion C5H9O4 + from intact uridine increased substantially with the desorption laser power and this only occurred at MPI wavelengths below 250 nm (full range studied 222-265 nm). We argue that this effect can only be rationalized plausibly in terms of changing populations of different isomers, tautomers, or conformers in the target as a function of the thermal desorption conditions. Furthermore, the wavelength threshold behavior of this thermally-sensitive MPI channel indicates a critical dependence on neutral excited state dynamics between the absorption of the first and second photons. The experimental results are complemented by density functional theory (DFT) optimizations of the lowest-energy structure of uridine and two further conformers distinguished by different orientations of the hydroxymethyl group on the sugar part of the molecule. The energies of the transitions states between these three conformers are low compared with the energy required for decomposition.
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This study examined the differences in quality of life (QoL) between active and sedentary schoolchildren and analyzed these differences by gender and weight status. A total of 1409 children, aged 11-13 years, from 20 schools located in 20 municipalities of the province of Cuenca were invited to participate in a cross-sectional study; 1073 children agreed (76.15% response rate), of which 536 (49.9%) were boys. QoL was measured with Child Health and Illness Profile-Child Edition (CHIP-CE), an instrument measuring children's perception of their own health using a Likert-type scale with five dimensions: satisfaction, comfort, resilience, risk avoidance, and achievement. Multivariate analysis of variance using the scores of the different CHIP-CE dimensions as dependent variables, physical activity, gender, and body mass index (BMI) category as fixed factors, and age as co-variate showed the following: (1) the scores of active children were significantly better than the scores of sedentary children for every dimension except risk avoidance; (2) there were no significant differences in QoL by BMI category; and (3) girls had better mean scores than boys for resilience, risk avoidance, and achievement, and worse scores for comfort. These results suggest that active children have a better QoL and that gender differences favoring boys diminish or even reverse to favor active girls.
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Exercício Físico/psicologia , Qualidade de Vida , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Análise Multivariada , EspanhaRESUMO
BACKGROUND: Cardiorespiratory fitness is a strong predictor of all-cause morbidity and mortality; nevertheless, the association between cardiorespiratory fitness and the risk of cancer remains unclear. Thus, the aim of this study was to synthetize the evidence on the relationship between cardiorespiratory fitness and the risk of several sites of cancer in men. METHODS: A computerised search in MEDLINE, EMBASE and Web of Science databases from their inception to 13th February 2019 was performed. Both fixed and random-effects models were used to calculate the pooled hazard ratio (HR) estimates and their 95% confidence intervals (CIs) to examine the effect of high and moderate versus low cardiorespiratory fitness on site-specific cancer (lung, colon/rectum, prostate) and all-sites cancer. RESULTS: Ten studies were included in the qualitative review, and seven of them were included in the meta-analysis. Using low cardiorespiratory fitness as the reference group, moderate and high levels of cardiorespiratory fitness were associated with a lower risk (HRs) of lung cancer, 0.53 (95% confidence interval [CI], 0.39 to 0.68) and 0.52 (95% CI, 0.42 to 0.61); colorectal cancer, 0.74 (95% CI, 0.55 to 0.93) and 0.77 (95% CI, 0.62 to 0.92) and all cancer sites, 0.86 (95% CI, 0.79 to 0.93) and 0.81 (95% CI, 0.75 to 0.87), respectively. CONCLUSIONS: Among men, cardiorespiratory fitness plays an important role in protecting against the risk of lung and colorectal cancer. Additionally, this protective effect was observed for all-sites cancer risk. These results show the importance of good cardiorespiratory fitness as a potential factor in cancer prevention.