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Electron microscopy of macromolecular structures is an approach that is in increasing demand in the field of structural biology. The automation of image acquisition has greatly increased the potential throughput of electron microscopy. Here, the focus is on the possibilities in Scipion to implement flexible and robust image‐processing workflows that allow the electron‐microscope operator and the user to monitor the quality of image acquisition, assessing very simple acquisition measures or obtaining a first estimate of the initial volume, or the data resolution and heterogeneity, without any need for programming skills. These workflows can implement intelligent automatic decisions and they can warn the user of possible acquisition failures. These concepts are illustrated by analysis of the well known 2.2 Å resolution β‐galactosidase data set. [ABSTRACT FROM AUTHOR]

Single‐particle analysis by electron microscopy is a well established technique for analyzing the three‐dimensional structures of biological macromolecules. Besides its ability to produce high‐resolution structures, it also provides insights into the dynamic behavior of the structures by elucidating their conformational variability. Here, the different image‐processing methods currently available to study continuous conformational changes are reviewed. In this paper, the existing image‐processing approaches in electron microscopy for the analysis of continuous conformational changes of biological macromolecules are reviewed. [ABSTRACT FROM AUTHOR]

Available data on the associations between motor competence (MC) and flexibility are limited and result inconclusive. This study aims to examine the relationship between flexibility and MC in children. The sample comprised 596 Portuguese children (47.1% girls) aged 9.7 ± 0.6 years. Motor competence was evaluated with the body coordination test, Körperkoordination Test für Kinder. Cardiorespiratory fitness (20-m shuttle run), muscular strength (curl-up and push-up tests), and flexibility (back-saver sit and reach and trunk-lift tests) were evaluated using the Fitnessgram Test Battery. Z-scores by age and gender for the physical fitness tests were constructed. Analysis of variance and regression analysis were performed. Participants in the healthy zone groups of both flexibility tests exhibited significantly better scores of MC than the participants under the healthy zone ( P < 0.001). Back-saver sit and reach and trunk-lift Z-scores, either individually or as a sum, were significant predictors of MC ( P < 0.05 for all) after adjustments for the other physical fitness components, age, body mass index, and socioeconomic status, in both genders. Our findings highlight the importance of promoting and developing flexibility, as well as the other health-related physical fitness components in schoolchildren to reach adequate levels of MC. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the associations between muscular fitness and inflammatory biomarkers and to investigate the relationship between muscular fitness and selected clustered inflammatory biomarkers in adolescents. This is a cross-sectional analysis with 529 adolescents (267 girls) aged 12-18 years. Handgrip strength and standing long jump tests assessed MF. Continuous scores of clustered inflammatory biomarkers (sum of Z-scores of C-reactive protein [ CRP], C3, C4, fibrinogen, and leptin); metabolic risk factor ( MRF) score (sum of Z-scores of SBP, triglycerides, ratio total cholesterol [ TC]/ HDL, HOMA- IR, and waist circumference [ WC]) were computed. Regression analyses showed an inverse association between muscular fitness score (β=−.204; P<.021) and clustered score of inflammatory biomarkers, adjusted for age, sex, pubertal stage, socioeconomic status, adherence to the Mediterranean diet, cardiorespiratory fitness ( CRF), MRF score, and body fat. Analysis of covariance showed that adolescents with an adverse inflammatory profile with low levels of muscular fitness exhibit the poorest MRF score ( F3,525=6.461; P<.001), adjusted for age, sex, pubertal stage, socioeconomic status, adherence to the Mediterranean diet, CRF, and body fatness. The inflammatory state seems to explain a significant part of the highest MRF score and in adolescents with high inflammatory status and low muscular strength. [ABSTRACT FROM AUTHOR]

Background/purpose Ultraviolet ( UV) radiation is responsible for sunburns, skin cancer, photoaging, and the production of reactive oxygen species ( ROS). The awareness on preventing these deleterious effects made the use of anti- UVB formulations an important part of population habits; however, despite the availability of several antioxidants capable of ROS scavenging, the pharmaceutical market lacks products associating UV filters with natural compounds of proven efficacy. Here, we investigated the effect of rutin, a flavonoid with antioxidant activity, associated with UVB filters in dermocosmetic preparations. Methods Formulations were assessed through its antioxidant activity, in vitro photoprotective effectiveness, photostability, and in vivo skin tolerance (hydration, transepidermal water loss, and erythema). Results Samples containing rutin were compatible with the human skin and presented a pronounced antioxidant potential, with scavenging activity values 75% higher than the ones containing only UVB filters. Although rutin could not prevent the sunscreens photodegradation post-irradiation, the bioactive compound significantly increased the formulations critical wavelengths, showing a photoprotective gain, especially in the UVA range. Conclusion In conclusion, the absorption in the UVA range, coupled with ROS scavenging potential, proved the positive effect of rutin applied to anti- UVB formulations, making this bioactive compound a promising candidate for photoprotection improvement. [ABSTRACT FROM AUTHOR]

A sensitive method was developed and experimentally validated for the in-line analysis and quantification of gaseous feed and product streams of separation processes under research and development based on column chromatography. The analysis uses a specific mass spectrometry method coupled to engineering processes, such as Pressure Swing Adsorption (PSA) and Simulated Moving Bed (SMB), which are examples of popular continuous separation technologies that can be used in applications such as natural gas and biogas purifications or carbon dioxide sequestration. These processes employ column adsorption equilibria on adsorbent materials, thus requiring real-time gas stream composition quantification. For this assay, an internal standard is assumed and a single-point calibration is used in a simple mixture-specific algorithm. The accuracy of the method was found to be between 0.01% and 0.25% (-mol) for mixtures of CO2, CH4, and N2, tested as case-studies. This makes the method feasible for streams with quality control levels that can be used as a standard monitoring and analyzing procedure. [ABSTRACT FROM AUTHOR]

The temporal variability in nitrogen (N) transport in the Corbeira agroforestry catchment (NW Spain) was analysed from October 2004 to September 2008. Nitrate (NO3-N) and total Kjeldahl nitrogen (TKN) loads and concentrations were determined at various timescales (annual, seasonal and event). The results revealed a strong intra-annual and inter-annual variability in N transport influenced by weather patterns and consequently by the hydrological regime. Mean annual export of total N in the catchment was 5.5 kg ha−1 year−1, with NO3-N being the dominant form. Runoff events comprised 10% of the study period but contributed 40 and 61% of the total NO3-N and TKN loads, respectively. The NO3-N and TKN concentrations were higher during runoff events than under baseflow conditions, pointing to diffuse sources of N. The mobilization of TKN during runoff events was attributed to surface runoff, while NO3-N might be related to subsurface and groundwater flow. Runoff events were characterized by high variability in N loads and concentrations. Higher variability was observed in N loads than in N concentrations, indicating that event magnitude plays an important role in N transport in this catchment; event magnitude explained approximately 96% of the NO3-N load. However, a combination of variables related to runoff event intensity (rainfall, discharge increase and kinetic energy) explained only 66% of the TKN load. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The effects of a 5-month intervention of football instruction and practice on the perceived psychological status and body composition of overweight boys were examined. Twelve boys (8-12 years; body mass index ≥ 85th percentile) participated in a structured 5-month football program, consisting of four weekly 60-90 min sessions with mean heart rate > 80% HRmax [football group ( FG)]. A control group ( CG) included eight boys of equivalent age from an obesity clinic located in the same area as the school. Both groups participated in two sessions of 45-90-min physical education per week at school. Indicators of perceived psychological status included body image, self-esteem, attraction to participation in physical activity, and perceived physical competence measured with standardized questionnaires. Body composition was evaluated using dual-energy X-ray absorptiometry. From baseline through 5 months, FG improved ( P < 0.05) in all indicators of psychological status (%Δ = +11.7 to +29.2%) compared with CG (%Δ = −32.1 to +0.5%). Changes in percentage body fat and lean body mass, however, did not differ between FG and CG. The findings suggest that a 5-month football intervention program was effective in improving the psychological status of overweight boys but did not significantly alter body composition. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to objectively assess pre-school children's total physical activity ( TPA) patterns and compliance with guidelines and to examine differences relative to parental education. Methods The sample consisted on 509 healthy pre-school children, aged 3-6 years recruited from kindergartens located in the metropolitan area of Porto, Portugal. The PA was assessed for 7 consecutive days by accelerometry. For TPA, we followed the guidelines of the National Association for Sport and Physical Education ( NASPE) (children who spent at least >120 min per day in active play). For TPA, we calculated the proportion of children who spent at least >120 min per day in active play and moderate-to-vigorous physical activity (MVPA), we calculated the proportion of children who spent at least >60 min per day in active play. Parental education was analysed according to the Portuguese education system. Results Children with parents in the highest education level were less active than children from low and middle education level ( P ≤ 0.001) in all patterns of PA (week and weekend). Regarding TPA during the week we found that the majority of children from low and middle parental education meet the NASPE guidelines. On the other hand, more than half the children from high parental education did not meet these recommendations ( P ≤ 0.001) and MVPA recommendations ( P ≤ 0.05). In both recommendations, children from low parental education were twice more likely to meet the recommendations compared with children belonging to high parental education. Conclusion Parent education was negatively associated with children's daily physical activity patterns and compliance with guidelines. [ABSTRACT FROM AUTHOR]

What is already known about this subject Diet and physical activity ( PA) are recognized as important factors to prevent abdominal obesity ( AO)., Studies have found an inverse relationship between milk intake or milk products and body weight and/or body fat in children and adolescents., Evidence suggests that low levels of PA are associated with AO in youth., What this study adds Our study explored the combined association of milk intake and PA on AO in adolescents, which are most often studied in isolation., Our findings suggested that adolescents with high milk intakes, regardless of whether they were active or low active, were less likely to have AO., Our findings could have a great epidemiological interest and bring important evidence in the field of AO management among adolescents., Background Diet and physical activity ( PA) are recognized as important factors to prevent abdominal obesity ( AO), which is strongly associated with chronic diseases. Some studies have reported an inverse association between milk consumption and AO. Objective This study examined the association between milk intake, PA and AO in adolescents. Methods A cross-sectional study was conducted with 1209 adolescents, aged 15-18 from the Azorean Archipelago, Portugal in 2008. AO was defined by a waist circumference at or above the 90th percentile. Adolescent food intake was measured using a semi-quantitative food frequency questionnaire, and milk intake was categorized as 'low milk intake' (<2 servings per day) or 'high milk intake' (≥2 servings per day). PA was assessed via a self-report questionnaire, and participants were divided into active (>10 points) and low-active groups (≤10 points) on the basis of their reported PA. They were then divided into four smaller groups, according to milk intake and PA: (i) low milk intake/low active; (ii) low milk intake/active; (iii) high milk intake/low active and (iv) high milk intake/active. The association between milk intake, PA and AO was evaluated using logistic regression analysis, and the results were adjusted for demographic, body mass index, pubertal stage and dietary confounders. Results In this study, the majority of adolescents consumed semi-skimmed or skimmed milk (92.3%). The group of adolescents with high level of milk intake and active had a lower proportion of AO than did other groups (low milk intake/low active: 34.2%; low milk intake/active: 26.9%; high milk intake/low active: 25.7%; high milk intake/active: 21.9%, P = 0.008). After adjusting for confounders, low-active and active adolescents with high levels of milk intake were less likely to have AO, compared with low-active adolescents with low milk intake (high milk intake/low active, odds ratio [ OR] = 0.412, 95% confidence intervals [ CI]: 0.201-0.845; high milk intake/active adolescents, OR = 0.445, 95% CI: 0.235-0.845). Conclusion High milk intake seems to have a protective effect on AO, regardless of PA level. [ABSTRACT FROM AUTHOR]

The search for new adsorbents with enhanced capacity and selectivity, suitable for application on large-scale simulated moving-bed units for separation of p-xylene, requires efficient, reliable, and fast adsorbent characterization methods for this specific separation. Fixed-bed experiments were carried out under the conditions of the Parex process to evaluate a faujasite-type zeolite as adsorbent for the separation of p-xylene from its isomers in the proportions of the real Parex feed stream. The experimental breakthrough curves were used to evaluate the selected adsorbent in terms of nonselective and selective volumes, adsorption capacity, selectivity, and productivity, which can be applied to identify the feasible separation region for different operating conditions. [ABSTRACT FROM AUTHOR]

Estimates of daily energy expenditure are important to studies of physical activity and energy balance. Objective measures are not always feasible and further research is needed to validate survey instruments and diaries. The study validates estimated activity energy expenditure (AEE) based on a 3-day diary protocol relative to AEE derived from uniaxial accelerometry in adolescents, 265 girls and 227 boys (12.5-16.4 years). Participants completed the diary and wore a GT1M Actigraph accelerometer on the same days. Height and weight were measured. Correlations between protocols were significant ( P<0.001) but moderate, r=0.65 in males and r=0.69 in females. The highest correlation occurred among males on Friday, r=0.74 ( P<0.01). Controlling for body mass, partial correlations between protocols decreased to 0.44 and 0.35 in males and females, respectively. About 97% of the cases fell within the limits of agreement in a Bland-Altman plot. The criterion of inclusion for the accelerometer excluded 18% of the initial sample. In summary, the 3-day diary was completed without any major problems and provided a reasonably valid alternative for assessing AEE. Concordance between methods was slightly lower for individuals with higher values of AEE. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the relationship between cardiac autonomic control derived from heart rate variability (HRV), high-sensitivity C-reactive protein (hs-CRP) and physical activity (PA) levels measured using accelerometers. A total of 80 healthy university students volunteered to participate in this study (20.56 ± 0.82 years, 1.36 ± 1.5 mg/L of hs-CRP). The participants were divided into groups based on tertiles of hs-CRP. Analysis of covariance adjusted to PA was used to assess group differences in HRV. Associations between hs-CRP, HRV indices and PA were analyzed using Pearson's correlation. The participants at the highest tertile of hs-CRP (tertile 3) had lower cardiac vagal modulation (SDNN, tertile 1=78.05 ± 5.9,tertile 2=82.43 ± 5.9,tertile 3=56.03 ± 6.1; SD1, tertile 1=61.27 ± 5.3, tertile 2=62.93 ± 5.4, tertile 3=40.03 ± 5.5). In addition, vagal indices were inversely correlated with hs-CRP but positively correlated with PA (SDNN r=−0.320, SD1 r=−0.377; SDNN r=0.304, SD1 r=0.299; P<0.05). Furthermore, the most physically active subjects had lower levels of hs-CRP and the highest levels of vagal modulation. [ABSTRACT FROM AUTHOR]

A better understanding of the different domains and characteristics of children's and adolescent's physical activity (PA) could be a strategy to clarify the association of this behaviour with the early development of cardiovascular risk factors. To examine the relationship between leisure time physical activity (LTPA) and sports competition activities (SCA) with high blood pressure (HBP) levels in a sample of children and adolescents from Porto, Portugal. This is a cross-sectional study, which comprised 503 boys and 572 girls, aged 8-17 years old. LTPA and SCA were assed by self-reported. Students were assigned as active and non-active in SCA or LTPA according to their self-reported participation. Participants were classified as HBP when they are above of the last quartile for systolic and/or diastolic BP adjusted for gender and age. Do not be engaged in LTPA (OR: 1.47; 95% CI: 1.12; 1.93) and SCA (OR: 1.36; 95% CI: 1.02; 1.81) was significantly associated with the likelihood of being HBP. However, when cardiorespiratory fitness (CRF) (OR: 1.23; 95% CI: 0.91; 1.67) and body mass index (BMI) (OR: 1.31; 95% CI: 0.98; 1.75) were included on SCA model, the association between SCA with HBP did not showed significant results. Children and adolescents who are not engaged in SCA or LTPA are more likely to be classified as having HBP; however, the relationship between SCA and HBP was dependent of CRF and BMI. Further, PA strategies should take these differences on the relationship between HBP, SCA and LTPA. [ABSTRACT FROM AUTHOR]

Aim: To analyse whether changes in physical activity index (PAI), screen time (ST: television, computer) and body mass index (BMI) made a contribution to longitudinal changes in fitness of children and adolescents. Additionally, we analysed the interaction between baseline fitness level and changes in fitness. Methods: This is a 3-year longitudinal study of 345 high school students aged 11–19 years. Students performed curl-ups, push-ups and 20-m shuttle run tests from Fitnessgram. PA and ST were evaluated using a standard questionnaire. Standardized scores of fitness tests were summed. Changes over time were calculated as Δ1 (2007 minus 2006), Δ2 (2008 minus 2007) and Δ3 (2008 minus 2006). Results: Changes in PAI were positively and independently associated with changes in fitness in Δ1, Δ2 and Δ3. Changes in BMI were negatively associated with changes in fitness in Δ3. Participants highly fit at baseline were those who showed positive changes in PAI over Δ3, decreased changes in ST and had the lowest increase in BMI over 3 years compared with those low-fit at baseline. Conclusions: Changes in BMI were associated with changes in fitness over 3 years. However, changes in PAI were the best predictor for changes in fitness in each year and over the 3 years of evaluation in youth. [ABSTRACT FROM AUTHOR]

The aim of the study was to characterize clinically and biochemically mucopolysaccharidosis type II (MPS II) heterozygotes. Fifty-two women at risk to be a carrier, with a mean age of 34.1 years (range 16–57 years), were evaluated through pedigree analysis, medical history, physical examination, measurement of iduronate sulfatase (IDS) activities in plasma and in leukocytes, quantification of glycosaminoglycans (GAGs) in urine, and analysis of the IDS gene. Eligibility criteria for the study also included being 16 years of age or older and being enrolled in a genetic counselling programme. The pedigree and DNA analyses allowed the identification of 40/52 carriers and 12/52 non-carriers. All women evaluated were clinically healthy, and their levels of urinary GAGs were within normal limits. Median plasma and leukocyte IDS activities found among carriers were significantly lower than the values found for non-carriers; there was, however, an overlap between carriers’ and non-carriers’ values. Our data suggests that MPS II carriers show lower plasma and leukocyte IDS activities but that this reduction is generally associated neither with changes in levels of urinary GAGs nor with the occurrence of clinical manifestations. [ABSTRACT FROM AUTHOR]

The Mediterranean area is regarded nowadays as one of the hot-spots of world biodiversity. The Baetic ranges in Spain have such a large number of endemic plant taxa that the territory has been recognized as a well-defined biogeographical unit. These endemic taxa tend to concentrate on disjunct highland areas that have been described consequently as 'highland islands'. Despite the importance and complexity of these sites, the research carried out so far has produced only descriptive classifications. These approaches overlook the relationships between the sites and do not serve to identify the main centres of endemism. Herein, multivariate analysis techniques (cluster analysis and reciprocal averaging) and the parsimony analysis of endemicity (PAE), applied to the 222 orophilous endemic taxa of the Baetic ranges, have been used to reveal the floristic similarities between the areas involved, to identify the centres of endemism and to re-assess the previous classifications. Four centres of endemism are defined, one siliceous and three calcareous. The most outstanding feature in the Baetic ranges is precisely the floristic difference between siliceous and calcareous mountains. Calcareous territories extend along a SW-NE axis in line with the oceanic-continental gradient. The nature of the soil in the vast siliceous and calcareous-dolomitic territories of the Sierra Nevada is probably the cause of the remarkable fioristic diversity. Not surprisingly, in our analysis these areas stand out as centres of endemism. We conclude that previous biogeographical classifications of the ranges are too rigid and do not properly reflect the floristic similarities of the area under study. [ABSTRACT FROM AUTHOR]

High concentrations of butyryl/isobutyrylcarnitine (C4-carnitine) in plasma with increase of ethylmalonic acid (EMA) in urine point to different genetic entities, and further investigations are required to differentiate the possible underlying defect. Here we report three unrelated cases, two neurologically affected and one asymptomatic, with this abnormal metabolite pattern due either to mutations in the ETHE1 gene or to a short-chain acyl-CoA dehydrogenase (SCAD) defect. [ABSTRACT FROM AUTHOR]

Background: The importance of movement behaviors for health is well-known, although few studies have examined the compliance with movement guidelines in preschoolers from different living contexts. This study reported the compliance with the 24-h movement behaviors guidelines among low-income Brazilian preschoolers from rural and urban areas, according to age., Methods: A total of 453 preschoolers (n = 222 urban), aged between 3 and 5 years, provided physical activity (PA) data (Actigraph wGT3X). Sleep duration, and screen time were parent-reported. Preschoolers were classified as compliant/non- compliant with the 24-h movement guidelines, according to age. The association between prevalence of compliance with the recommendations and the children's living setting were estimated (SPSS; 27.0)., Results: Preschoolers were active (mean = 299.19 ± 76.42; and 369.76 ± 95.56 min/day in urban and rural areas, respectively), though moderate-to-vigorous physical activity (MVPA) time was below the 60 daily minutes recommended in both urban and rural settings (mean = 38.39 ± 21.36; and 47.32 ± 24.28, respectively). None of the urban children complied with the three recommendations simultaneously, while in the rural area, only 2.6% were compliant. Single movement behaviors compliances in the urban setting were 6.8%, 28.8% and 5.4% for PA, sleep, and screen time, respectively; while for rural settings were 16.5%, 21.2%, and 7.4%. Living in the rural area was related to the compliance with PA recommendation for the 5-year-old preschoolers., Conclusion: In both urban and rural Brazilian areas, very few preschoolers are compliant with the guidelines, and more than one third of the children do not comply with any of the recommendations. Strategies and programs to promote compliance with movement behaviors guidelines should consider children's living setting and their age groups., (© 2024 Wiley Periodicals LLC.)

From the year 2000, the United States Fire Administration (USFA) has been recording all line-of-duty deaths in the fire service. Stress or overexertion caused 1096 out of 2598 total line-of-duty deaths in the United States from 2000 to 2021. Those deaths due to stress or overexertion were further classified as myocardial infarction (90%), cerebrovascular accident (6.8%), other (2.6%), and heat exhaustion (0.6%). Environmental heat exposure is a concern in firefighting, as firefighters work in extreme conditions, such as high ambient temperatures, while wearing protective clothing. Heat stress is not only hazardous to the cardiovascular system, but may accentuate muscle fatigue and overexertion. In addition, overexertion itself is related to increased incidence of musculoskeletal injuries, usually to the lower extremities. Further, there is a strong physiological mechanistic link to suggest that the increased occupational heat exposure and thermoregulatory strain firefighters experience may be a stressor that increases the risk of injuries. This commentary hopes to show the need for further research on the effects of occupational exposures and physiological strain in the fire service., (© 2023 Wiley Periodicals LLC.)

Background: Accruing adequate daily amounts of time spent on movement behaviors (physical activity (PA), sedentary behavior (SB), and sleep) in childhood has been associated with positive short and long-term health outcomes. Nonetheless, how waking time is distributed across PA and SB among preschoolers who are short and adequate sleepers at night is unknown., Aim: This study investigated: (1) if there are differences in a movement behaviors composition among adequate and short nocturnal sleepers; and (2) the association between preschoolers' time spent in PA, SB, and sleep among adequate and short nocturnal sleepers., Methods: A total of 270 preschoolers (132 boys; 3.97 ± 0.81 years old; 15.48 ± 1.62 kg/m 2 ) participated in this study. PA and SB were assessed using accelerometry (model wGT3X). Sleep duration was assessed through a parental-proxy interview, and preschoolers were stratified as short and adequate sleepers, according to attendance to international sleep duration guidelines. Compositional data analysis was used to explore the time-use patterns of behaviors among adequate and short sleepers., Results: Short sleepers spent 64 min less time asleep, accumulated 32 min in more sedentary time (p = .005, Cohen's d = 0.36, Bayes Factor: 6.17), and 24 min more in light PA (p = .0005, Cohen's d = 0.44, Bayes Factor: 46.37) compared to adequate sleepers., Conclusions: Being a short sleeper was associated with greater time spent in SB and light PA during their waking hours. The health implications of movement behaviors composition among short sleep preschoolers should be further investigated., (© 2021 Wiley Periodicals LLC.)

Objective: To qualify a 3C approach model of dual-energy X-ray absorptiometry (DXA) to estimate multicomponent resting energy expenditure (REE) referenced by indirect calorimetry (IC)., Methods: A sample of 155 college students, of both sexes (18-30 years old) was evaluated. Anthropometric measures, REE by IC, and whole-body DXA-scans were performed. The REE for each body component was determined after transforming the components from the molecular (DXA) to the organ tissue level. Bland-Altman and proportional bias analyses were used to verify agreement between REE measured (REE IC ) and estimated (REE DXA )., Results: Statistically significant differences were found for all sex comparisons (P < .001), except for age (P = .950). Differences from the final sex-specific models' were not found between REE IC and REE DXA (P > .05). Men also presented greater expenditure (P < .001) in each component, except for adipose tissue. The plots confirmed the validity of the model for both sexes, with low difference values between the measured and estimated REE. The mean of the differences of REE IC and REE DXA showed heteroscedasticity of the data for men (P = .004). The same error tendency was not evident for women (P = .333)., Conclusions: This 3C model, estimating REE from a multicomponent approach, allows a new application of DXA as tool for understanding intraindividual differences in terms of the mass of metabolically active tissue. Sex and populational differences should be taken in account. Consequently, we present qualified sex-specific DXA models that can be applied in different contexts such as health and sports, besides considering interpersonal differences in terms of energy expenditure., (© 2020 Wiley Periodicals LLC.)

Objective: The purpose of this study was to examine the longitudinal associations between cardiorespiratory fitness and health-related quality of life (HRQoL) in a sample of adolescents, and to determine whether changes in cardiorespiratory fitness were associated with HRQoL over a 2-year follow-up., Methods: This is a longitudinal analysis with 571 Portuguese adolescents (274 boys and 297 girls) aged 12-18 years. HRQoL was measured with the Kidscreen-10 questionnaire; the 20 m shuttle-run was used to estimate cardiorespiratory fitness; socioeconomic status was assessed with the Family Affluence Scale; and pubertal stage was assessed with Tanner stages. Linear regression and analysis of covariance (ancovas) were used to examine the associations between cardiorespiratory fitness and HRQoL., Results: HRQoL decreased over a 2-year period both in boys and girls (P < .05). Moreover, girls at baseline and at follow-up reported significantly lower HRQoL values than boys (between subjects P < .001). After adjustments for potential confounders, regression analyses showed significant cross-sectional associations between cardiorespiratory fitness and HRQoL both at baseline (B = 0.095; P = .023) and at follow-up (B = 0.090; P = .012). ancova showed that adolescents whose cardiorespiratory fitness decreased over time exhibited lower scores of HRQoL at follow-up, compared to those with persistent high cardiorespiratory fitness; this held after adjustments for age, sex, socioeconomic status, and pubertal stage., Conclusions: Changes in cardiorespiratory fitness during adolescence were associated with HRQoL over a 2-year period. This study suggests that improving cardiorespiratory fitness could be an important strategy in improving the HRQoL of adolescents., (© 2019 Wiley Periodicals, Inc.)

Objectives: To explore the association between sedentary behavior time (SB), and waist-to-height ratio (WHtR) in preschool children., Methods: This study included 646 preschool children (4- to 6-years old). WHtR was calculated as the ratio of waist/height with a cutoff of 0.5 used to define risk of abdominal obesity. Sedentary behavior was measured during 7 consecutive days by accelerometer. Logistic regression was used to determine the association between SB and WHtR., Results: The prevalence of central obesity (WHtR) was 52.4 and 39.2% for girls and boys, respectively. Boys classified as being at risk for central obesity were more likely to spend more time in SB (OR: 1.6; CI: 1.1-2.5; P ≤ 0.05), adjusted by age (P ≤ 0.001)., Conclusions: Our data suggested that boys classified as having higher SB were more likely to having more central obesity. Am. J. Hum. Biol. 28:746-748, 2016. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Objectives: This study examined the utility of the Ruiz et al. cut-points when examining body mass index (BMI) and resting blood pressure in young people., Methods: Two hundred fifty-six children (154 girls and 102 boys) aged 7-16 years underwent assessment of BMI, physical maturation, resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) and cardiorespiratory fitness using breath by breath gas analysis during treadmill testing to exhaustion., Results: Results from a series of 2 (fit vs. unfit) × 2 (gender) ways analysis of covariance, controlling for maturation indicated higher SBP in the unfit group compared to the fit group (P = 0.001), higher DBP in the unfit group compared to the fit group (P = 0.04) and higher BMI (in unfit) than fit children (P = 0.0001). Males had significantly higher BMI than females (P = 0.04). Maturation as a covariate was significantly and positively associated with SBP (P = 0.003), DBP (P = 0.004), and BMI (P = 0.001)., Conclusions: This study suggests that the Ruiz et al. cut-points are valid in distinguishing between children with higher and lower BMI and resting BP values., (© 2014 Wiley Periodicals, Inc.)

Objectives: To examine the efficacy of aerobic fitness thresholds in predicting weight status and cardiovascular disease risk (CVD) in young people., Methods: A cross-sectional school-based study was conducted on 414 Portuguese young people (235 girls and 179 boys) aged 10-16 years (Mean age ± SD = 13.6 ± 1. 8 years). Height and mass were assessed to determine body mass index (BMI). The 20 m multistage shuttle-fitness test (MSFT) was used as an estimate of aerobic fitness. Capillary blood sampling was used to determine: total cholesterol, triglycerides, high-, and low-density lipoprotein. These were combined with measures of systolic blood pressure as z-scores and summed to create a CVD risk score., Results: Analysis of covariance, controlling for sexual maturation, indicated a significant main effect for BMI as a result of fitness category (P = 0.0001). When applied to CVD risk data, there was no difference between "fit" and "unfit" groups (P = 0.136). Subsequent receiver operating curve (ROC) analysis indicated significant diagnostic accuracy of 20 mMSFT performance for boys and girls (both P = 0.0001) with subsequent cut-offs of estimated VO2 peak of 49.5 ml kg(-1) min(-1) for girls and 47.7 ml kg(-1) min(-1) for boys. When applied to BMI and CVD risk data, there was a significant main effect as a result of fitness category for BMI (P = 0.0001) and CVD risk score (P = 0.0001)., Conclusions: Recently established cut-points proposed by Boddy et al. (Boddy et al. [2012]: PLoS One 7(9): e45755) show validity in distinguishing between weight status but not CVD risk in Portuguese young people. Alternative ROC generated cut points significantly predicted BMI and CVD risk in this sample., (Copyright © 2013 Wiley Periodicals, Inc.)

Objectives: To compare inverted body mass index (iBMI, cm(2) /kg) and body mass index (BMI, kg/m(2) ) as predictors of body fatness, metabolic risk, and cardiovascular fitness in adolescents., Methods: A cross-sectional school-based study was conducted on 445 Portuguese adolescents (252 girls and 193 boys) aged 10-17 years. Height and body mass were assessed to determine iBMI and BMI, percent body fatness was determined from skinfold measures (tricep, subscapular) using the Slaughter et al. (1988: Hum Biol 60: 709-723) regression equation and cardiorespiratory fitness (CRF) was assessed using the 20-m shuttle run test. Capillary blood sampling was used to determine: Total cholesterol, triglycerides, high, and low density lipoprotein. These were combined with measures of systolic blood pressure and waist circumference as z-scores. Metabolic risk (MRS) was constructed by summing the z-scores., Results: iBMI and BMI were both significantly related to percent body fatness, CRF and MRS (all P = 0.005 or better). BMI was not normally distributed (P = 0.0001), whereas iBMI was (P > 0.05). Regression analysis identified that iBMI and BMI, both alongside for age, were significant predictors of percent body fatness, CRF and MRS (all P = 0.005 or better). Compared with BMI, iBMI was a similar predictor of CRF, MRS and body fatness., Conclusions: iBMI offers a biologically sound alternative to BMI to assess the effect of weight status on MRS and CRF in adolescents and allows appropriate use of parametrical statistical techniques without changing the conclusions drawn from such data., (Copyright © 2012 Wiley Periodicals, Inc.)

Objective: The rate-pressure product (RPP) has strong correlation with the maximal oxygen consumption and is an indicator of myocardium stress being considered as the best indirect method to measure myocardial oxygen consumption. However, to the best of our knowledge, no studies have addressed in preschool children. The aim of this study was to analyze the influence of percentage of body fat (%BF) and physical activity (PA) patterns on RPP at Rest (RPPrest) as a marker of cardiac load in Preschool children., Methods: The study comprised 593 preschool children aged 3-6 years-old. Heart rate (HR), systolic (SBP), and diastolic (DBP) blood pressure were taken at rest. The RPP was then calculated. The %BF was estimated from four skinfolds thicknesses and PA was assessed during 7 consecutive days by accelerometry., Results: Our data showed that only %BF (P ≤ 0.001) and vigorous PA (P ≤ 0.05) contributed significantly toward RPPrest variation. However, the multivariate analysis showed that only %BF (P ≤ 0.05) had a significant influence on RPPrest variation., Conclusion: These findings suggest that on preschoolers there is an association between RPP at rest and %BF., (Copyright © 2012 Wiley Periodicals, Inc.)

Background: Our primary aim was to investigate the associations that components of metabolic syndrome and physical activity have with cardiac autonomic nervous system activity as estimated by heart rate variability (HRV) in young adults free of metabolic abnormalities. We also aimed to identify predictors of 3-year changes in HRV., Methods: Physical activity was assessed annually in 163 healthy participants over 3 years (2008-2010). Components of metabolic syndrome measured annually were; waist circumference, systolic blood pressure, high-density lipoprotein, triglycerides, glucose, and C-reactive protein. A linear mixed regression model was used to assess associations between HRV, metabolic syndrome components and physical activity. Linear regression was used to identify predictors of changes in HRV., Results:  Metabolic syndrome components were negatively associated with HRV indices and higher heart rate, while physical activity was associated with higher HRV and lower heart rate. Physical activity and inflammation were predictors of positive and negative changes in HRV indices, respectively., Conclusions:  In participants without significant metabolic abnormalities, metabolic syndrome components were still associated with less favourable HRV profiles. Physical activity and inflammation were both able to predict changes in HRV, albeit in different directions. It appears that the process of autonomic dysfunction starts at a young age and may be mediated in part by inflammation. Metabolic syndrome prevalence is increasing in younger populations; promoting the metabolic and autonomic benefits of exercise remains imperative., (Copyright © 2012 John Wiley & Sons, Ltd.)

Objectives: This study aimed to examine the independent association of cardiorespiratory fitness (CRF) and physical activity (PA) with overweight and total and abdominal obesity in an elderly population., Methods: A total of 112 males and 185 females, 65-103 years, were assessed for PA with accelerometers and results from six-minute walk test were used as a CRF marker. Waist circumference was dichotomized into normal or abdominal obesity and BMI was categorized into normal, overweight, or obesity. Binary logistic regression models were performed., Results: Binary logistic regressions showed that, moderate-to-vigorous PA (MVPA) predicted OR for abdominal obesity (OR = 1.4%; P = 0.026), obesity (OR = 2.9%; P < 0.001), and both conditions coupled (OR% = 4.0%; P < 0.001). Even adjusting for CRF, MVPA remained a significant predictor. CRF was associated with OR for abdominal obesity (OR = 0.4%; P = 0.001)., Conclusion: In conclusion, higher CRF is associated with lower risk for abdominal obesity in elderly. Independently MVPA predicts OR for obesity, abdominal obesity, and the cluster of both conditions., (2011 Wiley Periodicals, Inc.)

The main goal of this study was to examine the association between sleeping quality with cardiorespiratory fitness (CRF) and obesity status (BMI) This was a cross-sectional study of 1,726 adolescent girls, aged 10 to 18 years. CRF was predicted by maximal multistage 20 m shuttle-run test according to procedures described from FITNESSGRAM. Children's BMI was classified according to International Obesity Task Force and sleeping quality was assessed by questionnaire. The prevalence of overweight and obesity was 21.2% and 5.7%, respectively. Sleeping quality was significantly associated with CRF (Rho = 0.17; P < 0.05), but not with BMI. Girls who were classified as fit were more likely (OR: 2.25; P < 0.05) to report better sleep quality compared to their unfit peers. Poor sleep quality was associated with lower CRF although no associations have been shown with BMI.

We analyzed the 5-year longitudinal relationship between cardiorespiratory fitness (CRF) and cardiovascular diseases (CVD) risk factors in children. A total of 153 students (66 boys and 87 girls) were evaluated in 1998 and 2003. Multilevel modeling was used to determine the effect of CRF across time (Model 1, adjusted for time and Model 2-Model 1 with further adjustment for gender and age). In both models, a significant main effect was found for body mass index (BMI) (P

The sample of this study comprised 9,991 adults who participated in the Azorean Physical Activity and Health Study, Portugal. Body mass index was calculated from self-reported weight and height and used as a depended variable. Physical activity was assessed by the International Physical Activity Questionnaire-short version, participants were classified in three categories according to their METs min/week values: low physical activity level, moderate physical activity level, and health-enhancing physical activity. Smoking status, alcohol consumption, and socio-economic status were also collected. Results showed that the prevalence of overweight and obesity was 33.5 and 18.8% in women, and 45.8 and 16% in men, respectively. The prevalence of health-enhancing physical activity individuals was 23.6% for women and 43.8% for men. Logistic regression analysis showed that age was a predictor of overweight and obesity, in both genders. Smoking status was negatively associated with overweight and obesity, in both genders. Men with low physical activity level and higher sitting time (>or=3 h/day) were more likely to be obese. Low socio-economic status and alcohol consumption were found to be predictors for overweight and obesity for women. In summary, the prevalence of overweight and obesity among Azorean adults is high. Targeted programs aimed to lower the prevalence of overweight and obesity, among the Azoreans, should focus on elderly, on women with low socio-economic status, and on men aged 26-40 years, due to the higher prevalence of overweight and obesity and low levels of physical activity observed in these groups., ((c) 2007 Wiley-Liss, Inc.)

The aim of this study was to compare the physical activity of overweight/obese children during days when they attended a physical activity program, and days when they did not. This is a cross-sectional intervention study of daily physical activity. The participants were referred by family, doctors, or hospital pediatricians to take part in a 10-month interdisciplinary, outpatient obesity intervention program for children. The subjects included 41 overweight and obese children aged 8-16 years, 19 boys (46%) and 22 girls (54%); BMI: 25.7 + 3.3 kg m(-2). The MTI Actigraph was used as an objective measure of daily physical activity over seven consecutive days. Physical activity program days presented a significantly higher percentage of time (4.68%) spent in moderate-to-vigorous activity compared with no physical activity program days (3.16%) and weekend (2.7%). The results of this study suggest that a physical activity program can help increasing daily physical activity in obese children, with a special focus on MVPA level. Our data point that obese children are less active at weekend than during weekdays., (Copyright 2007 Wiley-Liss, Inc.)