Sobrecarga cardiovascular em mulheres praticantes de ciclismo Indoor

A prática do ciclismo indoor em academias é habitualmente comercializada com foco no condicionamento cardiorrespiratório e na perda de peso. As sessões costumam simular percursos com trechos de subidas, o que muitas vezes se associa com elevada demanda cardiovascular. Foram avaliadas 23 voluntárias (36.9±11.3 anos; IMC 24.0±4.1 kg/m2). Calculou-se a frequência cardíaca (FC) média de 3 aulas, com frequencímetro Polar RS800 no início da aula (FC_INÍCIO), pico do esforço (FC_PICO), final da aula (FC_FIM) e após alongamento (FC_PÓS). Calcularam-se os tempos de permanência nas intensidades muito vigorosa (MV, ≥94%FCmax), vigorosa (VG, 77-93%FCmax), moderada (MD; 64-76%FCmax) e leve (LV; ˃64%FCmax). Dada distribuição não normal (Shapiro-Wilk˂0.05) foi utilizado o teste de Friedman para comparação da FC (início, pico, fim e pós), com teste post-hoc de Dunn, sempre ao nível de 5% de significância. Observaram-se a FC_PICO 167bpm (127-186) maior (p<0,05) que: FC_INÍCIO 90bpm (60-122), FC_FIM 135bpm (111-150) e FC_PÓS 113bpm (89-137). A FC_FIM foi maior que FC_INÍCIO, similar a FC_PÓS, que foi similar a FC_INÍCIO (p<0,05). A FC_INÍCIO teve aumento médio para FC_PICO de 74bpm (34-111) ou 80.9% (36,6-185). A FC_FIM reduziu 26 bpm (13-57), equivalente a 19% (11.4-44.2), comparada a FC_PICO. Observou-se elevada sobrecarga cardiovascular. A maior parte da aula (57,4%) os indivíduos permaneceram nas intensidades vigorosa e muito vigorosa

Avaliação objetiva do nível de atividade física, do comportamento sedentário e da aptidão cardiorrespiratória de bombeiros militares

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Educação Física, Programa de Pós-Graduação em Educação Física, 2018.Introdução: A atividade profissional de bombeiros é reconhecida pela exposição constante a riscos ocupacionais, intenso estresse físico e emocional. Entretanto inexistem estudos nacionais que avaliem objetivamente o nível de atividade física e o esforço cardiovascular a que bombeiros são expostos no período de 24 horas de atividade ocupacional de rotina. Objetivos: Avaliar a atividade física (ATF), comportamento sedentário (CS) e intensidade de esforço imposta ao sistema cardiovascular de bombeiros militares em prontidão no quartel pelo período de 24 horas. Indivíduos: Foram avaliados 33 bombeiros do sexo masculino, com mediana de idade de 35 (28 – 47) anos sem restrições médicas para o desempenho profissional. Métodos: Avaliaram-se a ATF de intensidade leve, moderada-vigorosa (MV), o CS e o esforço cardiovascular durante o período de 24 horas de atividade operacional. A ATF foi avaliada por meio da acelerometria e a sobrecarga cardiovascular por meio do comportamento da frequência cardíaca (FC). A análise foi realizada em conjunto (n= 33) e por sub-grupos: G1: atividades diversas; G2: atuação em combate a incêndio florestal de pequeno a médio porte no Distrito Federal; e G3: atuação em combate a incêndio florestal de grande porte na Chapada dos Veadeiros. Foram descritos os tempos de permanência em CS, em ATF leve, ATF-MV, o número de passos e o gasto energético. Também foram calculados os tempos absolutos e relativos de permanência em quatro zonas de intensidade de esforço físico (leve, moderada, vigorosa e muito vigorosa) de acordo com a FC. Resultados: Observou-se que durante o período de prontidão no quartel os voluntários acumularam em média 35% tempo em CS, 52% em ATF leve, 12% em ATF-MV, foram acumulados média de 13.444 passos e o gasto energético estimado foi de 1.404 kcal. Na análise entre grupos foi demonstrado que o G3 acumulou mais ATF de intensidade leve que o G2 (p= 0,02). Foi observado que a prevalência de voluntários ativos durante o plantão de 24h variou entre 45% a 97% a depender do critério e/ou método de avaliação. De acordo com a FC foram despendidos em média 17h:26min em atividade de intensidade leve (≤64% da FCmax), 41 min em atividade moderada (64%< FC ≤76% da FCmax), 23 min em vigorosa (76%< FC <94% da FCmax) e 4 min em atividade muito vigorosa (≥94% da FCmax). Conclusão: De modo global os dados confirmam as hipóteses de que os bombeiros são uma categoria profissional ativa; com rotina de trabalho em regime de prontidão de 24h que se associa a reduzido tempo em CS e a longos períodos de ATF leve intercalados com ATF-MV. A atividade de CIF se mostrou de maior sobrecarga cardiovascular que as demais. Nossos achados reforçam a importância de realização de triagem clínica e física para a seleção e acompanhamento contínuo de bombeiros militares em atividade operacional.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).Background: Firefighters are widely recognized for having a hazardous occupation. Job activities expose firefighters to different risk factors, physical stressors and emotional stress. However, there are no national studies that objectively assess the level of physical activity (PAL) and cardiovascular strain at which firefighters are exposed within 24 hours on-duty period. Objective: We aimed to evaluate the PAL, sedentary behavior (SB) and cardiovascular strain of military firefighters during 24 hour on-duty period. Subjects: We evaluated 33 male firefighters aged 35 (28 – 47) years with no medical restrictions for firefighting activity. Methods: We evaluated the light physical activity, the moderate-vigorous physical activity (MVPA), the SB and the cardiovascular strain during the 24-hour on-duty period. The PAL was assessed by accelerometry (ActiGraph-GT3X+®) and the cardiovascular strain was assessd by heart rate (HR) measured by an HR transmitter (H10-Polar®). The analysis was performed together (n= 33) and by sub-groups: G1: diverse activities; G2 action in small to medium size forest fire in the Distrito Federal; and G3: action in a large forest fire in the Chapada dos Veadeiros, Brazil. We analysed the time spent in SB, in light activity, in moderate to vigorous, the number of steps and the energy expenditure. We calculated the absolute and relative time spent in four intensity zones of physical activity (light, moderate, heavy and very heavy) according to the HR. Results: It was observed that on-duty period the volunteers accumulated an average of 35% on SB, 52% on light intensity activity, and 12% on MVPA. The volunteers accumulated 13,444 steps/day and expenditure 1,404 kcal/day. The analysis between groups was provided by the G3 accumulated more light physical activity than the G2 (p= 0.02). It was observed that the prevalence of active volunteers during the 24h on-duty ranged from 45% to 97% depending on the criteria and/or evaluation method. According to HR the the time spent in light intensity was 17h:26m in (≤64% of maximal HR), 41 min in moderate intensity physical activity (64%< FC ≤76% of maximal HR), 23 min in vigorous intensity (76%< FC <94% of maximal HR) and 4min on very heavy intensity (≥94% of maximal HR). Conclusion: Overall, the data confirm the hypothesis that firefighters are an active professional category; with a 24-hour on-duty period was associated with reduced CS time and long periods of light physical activity interspersed with MVPA. The firefighters during forest fire suppression activity was exposed a high cardiovascular strain. Our findings reinforce the necessity medical evaluation and regular physical training of these professionals

Arrival of Paleo-Indians to the Southern Cone of South America: New Clues from Mitogenomes

With analyses of entire mitogenomes, studies of Native American mitochondrial DNA (mtDNA) variation have entered the final phase of phylogenetic refinement: the dissection of the founding haplogroups into clades that arose in America during and after human arrival and spread. Ages and geographic distributions of these clades could provide novel clues on the colonization processes of the different regions of the double continent. As for the Southern Cone of South America, this approach has recently allowed the identification of two local clades (D1g and D1j) whose age estimates agree with the dating of the earliest archaeological sites in South America, indicating that Paleo-Indians might have reached that region from Beringia in less than 2000 years. In this study, we sequenced 46 mitogenomes belonging to two additional clades, termed B2i2 (former B2l) and C1b13, which were recently identified on the basis of mtDNA control-region data and whose geographical distributions appear to be restricted to Chile and Argentina. We confirm that their mutational motifs most likely arose in the Southern Cone region. However, the age estimate for B2i2 and C1b13 (11–13,000 years) appears to be younger than those of other local clades. The difference could reflect the different evolutionary origins of the distinct South American-specific sub-haplogroups, with some being already present, at different times and locations, at the very front of the expansion wave in South America, and others originating later in situ, when the tribalization process had already begun. A delayed origin of a few thousand years in one of the locally derived populations, possibly in the central part of Chile, would have limited the geographical and ethnic diffusion of B2i2 and explain the present-day occurrence that appears to be mainly confined to the Tehuelche and Araucanian-speaking grou

NÍVEL DE ATIVIDADE FÍSICA E QUALIDADE DE VIDA DE POLICIAIS

Resumo: Bons níveis de atividade física e qualidade de vida são fatores determinantes para uma condição humana saudável, sendo imprescindível ao âmbito da prática laboral policial. O objetivo deste trabalho foi investigar os níveis de atividade física e de qualidade de vida de policiais militares de um dos estados da região Norte do Brasil. Uma pesquisa epidemiológica realizada com a aplicação do IPAQ e do WHOQOL-Bref. As variáveis foram analisadas por meio de estatística descritiva apresentadas em medidas de tendência central e de dispersão. &nbsp;Os resultados demonstraram um bom nível de qualidade de vida, com os maiores escores no domínio social e os menores no domínio ambiental. Sobre o nível de atividade física verificou-se que a maioria dos policiais militares pesquisados são ativos fisicamente. Contudo, a análise do IMC apresentou que a maioria dos profissionais pesquisados está classificada como sobrepesados ou obesos. Palavras-chave: Qualidade de Vida. Atividade Física. Policial Militar. Saúde Profissional Abstract: Good levels of physical activity and quality of life are determining factors for a healthy human condition, being essential in the police sphere. The aim of this study was to investigate the levels of physical activity and quality of life of military police officers from one of the states of northern Brazil. An epidemiological research conducted with the application of IPAQ and WHOQOL-Bref. The variables were analyzed using descriptive statistics presented in measures of central tendency and dispersion. The results showed a good quality of life, with the highest scores in the social domain and the lowest in the environmental domain. Regarding the level of physical activity it was found that most of the military police surveyed are physically active. However, BMI analysis showed that most professionals surveyed are classified as overweight or obese. Keywords: Quality of Life. Physical Activity. Military Police.&nbsp;Professional Healt

From nuclear track characterization to machine learning based image classification in neutron autoradiography for boron neutron capture therapy

Knowledge of the 10B microdistribution is of great relevance in BNCT studies. Since 10B concentration assesment through neutron autoradiography depends on the correct quantification of tracks in a nuclear track detector, image acquisition and processing conditions should be controlled and verified, in order to obtain accurate results to be applied in the frame of BNCT. With this aim, an image verification process was proposed, based on parameters extracted from the quantified nuclear tracks. Track characterization was performed by selecting a set of morphological and pixel-intensity uniformity parameters from the quantified objects (area, diameter, roundness, aspect ratio, heterogeneity and clumpiness). Their distributions were studied, leading to the observation of varying behaviours in images generated by different samples and acquisition conditions. The distributions corresponding to samples coming from the BNC reaction showed similar attributes in each analyzed parameter, proving to be robust to the experimental process, but sensitive to light and focus conditions. Considering those observations, a manual feature extraction was performed as a pre-processing step. A Support Vector Machine (SVM) and a fully dense Neural Network (NN) were optimized, trained, and tested. The final performance metrics were similar for both models: 93%-93% for the SVM, vs 94%-95% for the NN in accuracy and precision respectively. Based on the distribution of the predicted class probabilities, the latter had a better capacity to reject inadequate images, so the NN was selected to perform the image verification step prior to quantification. The trained NN was able to correctly classify the images regardless of their track density. The exhaustive characterization of the nuclear tracks provided new knowledge related to the autoradiographic images generation. The inclusion of machine learning in the analysis workflow proves to optimize the boron determination process and paves the way for further applications in the field of boron imaging.Fil: Viglietti, Julia S.. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Departamento de Radiobiología; ArgentinaFil: Espain, Maria Sol. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Departamento de Radiobiología; ArgentinaFil: Díaz, Rodrigo Fernando. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro Internacional de Estudios Avanzados; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Ciencias Fisicas. - Universidad Nacional de San Martin. Instituto de Ciencias Fisicas.; ArgentinaFil: Nieto, Luis Agustin. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología. Centro Internacional de Estudios Avanzados; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Instituto de Ciencias Fisicas. - Universidad Nacional de San Martin. Instituto de Ciencias Fisicas.; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Constituyentes; ArgentinaFil: Szewc, Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. University of Cincinnati; Estados UnidosFil: Bernardi, Guillermo Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Rodríguez, Luis M.. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fregenal, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Saint Martin, María Laura Gisela. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Departamento de Radiobiología; ArgentinaFil: Portu, Agustina Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; Argentina. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Departamento de Radiobiología; Argentin

Extending neutron autoradiography technique for boron concentration measurements in hard tissues

The neutron autoradiography technique using polycarbonate nuclear track detectors (NTD) has been extended to quantify the boron concentration in hard tissues, an application of special interest in Boron Neutron Capture Therapy (BNCT). Chemical and mechanical processing methods to prepare thin tissue sections as required by this technique have been explored. Four different decalcification methods governed by slow and fast kinetics were tested in boron-loaded bones. Due to the significant loss of the boron content, this technique was discarded. On the contrary, mechanical manipulation to obtain bone powder and tissue sections of tens of microns thick proved reproducible and suitable, ensuring a proper conservation of the boron content in the samples. A calibration curve that relates the 10B concentration of a bone sample and the track density in a Lexan NTD is presented. Bone powder embedded in boric acid solution with known boron concentrations between 0 and 100 ppm was used as a standard material. The samples, contained in slim Lexan cases, were exposed to a neutron fluence of 1012 cm−2 at the thermal column central facility of the RA-3 reactor (Argentina). The revealed tracks in the NTD were counted with an image processing software. The effect of track overlapping was studied and corresponding corrections were implemented in the presented calibration curve. Stochastic simulations of the track densities produced by the products of the 10B thermal neutron capture reaction for different boron concentrations in bone were performed and compared with the experimental results. The remarkable agreement between the two curves suggested the suitability of the obtained experimental calibration curve. This neutron autoradiography technique was finally applied to determine the boron concentration in pulverized and compact bone samples coming from a sheep experimental model. The obtained results for both type of samples agreed with boron measurements carried out by ICP-OES within experimental uncertainties. The fact that the histological structure of bone sections remains preserved allows for future boron microdistribution analysis.Fil: Provenzano, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Olivera, María Silvina. Comisión Nacional de Energía Atómica; ArgentinaFil: Saint Martin, María Laura Gisela. Comisión Nacional de Energía Atómica; ArgentinaFil: Rodriguez, Luis Miguel. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Fregenal, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Thorp, Silvia Inés. Comisión Nacional de Energía Atómica; ArgentinaFil: Pozzi, Emiliano César Cayetano. Comisión Nacional de Energía Atómica; ArgentinaFil: Curotto, Paula. Comisión Nacional de Energía Atómica; ArgentinaFil: Postuma, Ian. Istituto Nazionale di Fisica Nucleare; ItaliaFil: Altieri, Saverio. Istituto Nazionale di Fisica Nucleare; Italia. Universita Degli Studi Di Pavia; ItaliaFil: González, Sara Josefina. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bortolussi, Silva. Istituto Nazionale di Fisica Nucleare; Italia. Universita Degli Studi Di Pavia; ItaliaFil: Portu, Agustina Mariana. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Cloud feedbacks in extratopical cyclones: insight from long-term satellite data and high-resolution global simulations

A negative extratropical shortwave cloud feedback driven by changes in cloud optical depth is a feature of global climate models (GCMs). A robust positive trend in observed liquid water path (LWP) over the last two decades across the warming Southern Ocean supports the negative shortwave cloud feedback predicted by GCMs. This feature has been proposed to be due to transitions from ice to liquid with warming. To gain insight into the shortwave cloud feedback we examine extratropical cyclone variability and the response of extratropical cyclones to transient warming in GCM simulations. Multi-Sensor Advanced Climatology Liquid Water Path (MAC-LWP) microwave observations of cyclone properties from the period 1992–2015 are contrasted with GCM simulations, with horizontal resolutions ranging from 7 km to hundreds of kilometers. We find that inter-cyclone variability in LWP in both observations and models is strongly driven by the moisture flux along the cyclone's warm conveyor belt (WCB). Stronger WCB moisture flux enhances the LWP within cyclones. This relationship is replicated in GCMs, although its strength varies substantially across models. It is found that more than 80 % of the enhancement in Southern Hemisphere (SH) extratropical cyclone LWP in GCMs in response to a transient 4 K warming can be predicted based on the relationship between the WCB moisture flux and cyclone LWP in the historical climate and their change in moisture flux between the historical and warmed climates. Further, it is found that that the robust trend in cyclone LWP over the Southern Ocean in observations and GCMs is consistent with changes in the moisture flux. We propose two cloud feedbacks acting within extratropical cyclones: a negative feedback driven by Clausius–Clapeyron increasing water vapor path (WVP), which enhances the amount of water vapor available to be fluxed into the cyclone, and a feedback moderated by changes in the life cycle and vorticity of cyclones under warming, which changes the rate at which existing moisture is imported into the cyclone. Both terms contribute to increasing LWP within the cyclone. While changes in moisture flux predict cyclone LWP trends in the current climate and the majority of changes in LWP in transient warming simulations, a portion of the LWP increase in response to climate change that is unexplained by increasing moisture fluxes may be due to phase transitions. The variability in LWP within cyclone composites is examined to understand what cyclonic regimes the mixed-phase cloud feedback is relevant to. At a fixed WCB moisture flux cyclone LWP increases with increasing sea surface temperature (SST) in the half of the composite poleward of the low and decreases in the half equatorward of the low in both GCMs and observations. Cloud-top phase partitioning observed by the Atmospheric Infrared Sounder (AIRS) indicates that phase transitions may be driving increases in LWP in the poleward half of cyclones

Nivel insuficiente de actividad física está asociado a menor calidad de vida y al estudio nocturno en universitarios del Distrito Federal

A prática de atividade física (AF) é essencial à saúde e à qualidade de vida (QV). Objetivo: Avaliar o nível de atividade física (NAF), a QV, fatores antropométricos e socioeconômicos em universitários do Distrito Federal. Métodos: Foram avaliados aleatoriamente 392 voluntários (43,6% homens). Empregaram-se os questionários IPAQ, WHOQOL e de tempo sentado (TS). Foram avaliados preditores do NAF com o emprego de regressão logística, assim como da QV estratificada por sexo, turno, NAF e renda. Resultados: Dos pesquisados, 51,4% eram insuficientemente ativos (IA) e mostraram menor QV do que os ativos (AT), nos domínicos físico (DOMF) e psicológico (DOMPS) (p 0,05). Menor NAF associou-se com maior TS e com aulas no turno noturno. A proporção de universitários IA foi elevada e se mostrou associada com menor QV no DOMF e DOMPS, elevado TS e com estudo noturno.Physical activity (PA) practice is an essential issue for health and quality of life (QOL). Objective: We analyzed the level of physical activity (LPA) and QOL in association with anthropometric and socioeconomics factors among undergraduate students from the Distrito Federal - Brazil. Methods: We randomly evaluated 392 volunteers (43.6% men). We employed the IPAQ + reported siting time (ST), and WHOQOL questionnaires. Logistic regression was used to evaluate LPA predictors. QOL was compared between sex, class period (day vs night), LPA and income. Results: Two hundred and one volunteers (51.4%) were insufficiently active (IA) and showed lower QOL than the active (AT) ones on physical (PHD) and psychological (PSD) domains (p< 0.05). Lower LPA was associated with greater ST and with the night shift study. We found a high proportion of IA students that was associated with lower QOL on PHD and PSD, higher ST and nightshift study

Computed Tomography and Adrenal Venous Sampling in the Diagnosis of Unilateral Primary Aldosteronism

Unilateral primary aldosteronism is the most common surgically correctable form of endocrine hypertension and is usually differentiated from bilateral forms by adrenal venous sampling (AVS) or computed tomography (CT). Our objective was to compare clinical and biochemical postsurgical outcomes of patients with unilateral primary aldosteronism diagnosed by CT or AVS and identify predictors of surgical outcomes. Patient data were obtained from 18 internationally distributed centers and retrospectively analyzed for clinical and biochemical outcomes of adrenalectomy of patients with surgical management based on CT (n=235 patients, diagnosed from 1994-2016) or AVS (526 patients, diagnosed from 1994-2015) using the standardized PASO (Primary Aldosteronism Surgical Outcome) criteria. Biochemical outcomes were highly different according to surgical management approach with a smaller proportion in the CT group achieving complete biochemical success (188 of 235 [80%] patients versus 491 of 526 [93%], P<0.001) and a greater proportion with absent biochemical success (29 of 235 [12%] versus 10 of 526 [2%], P<0.001). A diagnosis by CT was associated with a decreased likelihood of complete biochemical success compared with AVS (odds ratio, 0.28; 0.16-0.50; P<0.001). Clinical outcomes were not significantly different, but the absence of a postsurgical elevated aldosterone-to-renin ratio was a strong marker of complete clinical success (odds ratio, 14.81; 1.76-124.53; P=0.013) in the CT but not in the AVS group. In conclusion, patients diagnosed by CT have a decreased likelihood of achieving complete biochemical success compared with a diagnosis by AVS