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Fat-Free Mass Index for body composition analysis in pediatric sport: a cross-sectional study
No full textBacKGround: analyzing fat free mass (ffM) helps sport professionals during the prescription of sport training for children and adolescents in a sport initiation program. in this way, it is possible to determine fat mass (fM) (ffM subtracted from total body weight) and design interventions to increase ffM and reduce %f, making it possible to maximize performance in relation to the physical demands of sport. however, there is still no reliable anthropometric index to analyze ffM in this population. The aim the present study was to develop the fat-free Mass index (ffMi) for pediatrics of both sexes. MeThodS: cross-sectional study with a sample composed of 254 pediatrics (139 males [age: 13.0±2.3] and 115 females [age: 12.5±2.2]), from a sports initiation school. We divided the sample into the groups: 1) development (n.=169); and 2) cross-validation (n.=85). The body composition was analyzed by dual-energy X-ray absorptiometry (dXa), in addition we acquired anthropometric data (height, body weight and hip circumference) for the development of the ffMi – pediatric (ffMip). By means of linear regression we tested the predictive power of ffM using dXa as a reference method, then we developed ffMip and tested its reliability and validity in relation to dXa. reSulTS: ffMip consisted of: -16.679 + (0.615 × body mass (kg)) - (2.601 × sex) + (0.618 × age(years)) - (0.332 × hip(cm)) + (0.278 × stature(cm)), where for sex 0 = male and 1 = female. For the FFM analysis, FFMIp showed no significant difference from DXA (P>0.05). It also showed significant accuracy (Cb>0.960), precision (ρ>0.990) and agreement (CCC>0.960) for both groups (development and cross-validation). concluSionS: pediatric ffMi proposed by this study proved to be valid for the analysis of fat-free mass in pediatric athletes of sports initiation of both sexes. © 2024 EDIZIONI MINERVA MEDICA.National Council for Scientific Development; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES; Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNP
Middle Cerebral Artery Occlusion in Acute Ischaemic Cerebrovascular Attack
No full textIschaemic stroke (CVA) is one of the leading causes of morbidity and mortality at a global and national level. We studied 35 patients, determined the arteries that presented a higher frequency of occlusion in acute ischemic stroke and identified the middle cerebral artery and the poste- rior cerebral artery. We consider it necessary that specialists can locate anatomically strokes in order to apply neuroprotective therapies to improve treatment options and preventing secondary obstructions
Aesthetic Facial Surgery: Contribution from the Anterior Mandible Osteotomy
No full textFacial aesthetic surgery has been modified in the last 15 years. Different procedures and soft/hard tissue facial surgeries realized concurrently allow surgeons to achieve demanding aesthetics targets. The aim of this paper is to show variations in the osteotomy of symphyses and parasymphyses mandible to obtain better esthetic results. A series of four patient cases is presented to analyze the surgical procedure, using a segmental osteotomy of the anterior mandible, median osteotomy of the mandible, and a combination of these procedures. The results show a versatility of these technique and new target with good esthetic results can be used. In conclusion, variations of the osteotomy in the anterior area of the mandible are used according to individual requirements of each case, and can be performed with a low morbidity
The impacts of environmental collaboration on the environmental performance of agri-food supply chains: a mediation-moderation analysis of external pressures
No full textAlthough researchers have investigated the relationship between inter-organisational collaboration and firm performance, there is scattered evidence on the relationship between environmental collaboration and environmental performance in agri-food supply chains. This study assesses the effects of environmental collaboration on five dimensions of environmental performance (greenhouse gas emissions management, energy management, food waste management, food safety management, and water footprint management) in agri-food supply chains, particularly when mediated and moderated by customer and regulatory pressures. This study used a survey of Chilean agri-food companies. The data were analyzed using partial least squares structural equation modelling. We found that environmental collaboration positively influences all five dimensions of environmental performance and that customer and regulatory pressures mediate this relationship. The dimension most affected by environmental collaboration was water footprint management. Finally, we provide recommendations for improving the environmental performance of companies in agri-food supply chains through collaboration. © 2024 Informa UK Limited, trading as Taylor & Francis Group.Andalusian Regional Government, (SEJ-132); Cátedra de Economía de la Energía y del Medio Ambiente; Departamento de Análisis Económico y Economía Política; Universidad Autónoma de Chile (Chile); Universidad de Sevilla; Pontificia Universidad Católica de Chile, UC; ‘Red Eléctrica de España at the University of Sevill
Effect of different exercise programs on lung function in people with chronic obstructive pulmonary disease: A network meta-analysis of RCTs
No full textBackground: Chronic obstructive pulmonary disease (COPD) has systemic consequences and causes structural abnormalities throughout the respiratory system. It is associated with a high clinical burden worldwide. Aim: A network meta-analysis was performed to determine the effects of exercise programs on lung function measured by forced expiratory volume in the first second (FEV1), FEV1 as a percentage of the predicted value (FEV1%) and forced vital capacity in people with COPD. Methods: A literature search was performed to March 2023. Randomized controlled trials on the effectiveness of exercise programs on lung function in people with COPD were included. A standard pairwise meta-analysis and a network meta-analysis for direct and indirect comparisons between intervention and control/nonintervention groups were carried out to calculate the standardized mean difference and 95 % CI. The risk of bias was assessed using the Cochrane Risk of Bias tool and the Grading of Recommendations, Assessment, Development, and Evaluation tool was used to assess the quality of the evidence. Results: 35 studies with a total sample of 2909 participants were included in this network meta-analysis. The highest standardized mean difference was for active mind body movement therapy programs versus control for FEV1 and FEV1% (0.71; 95 % CI 0.32 to1.09; and 0.36; 95 % CI 0.15 to 0.58, respectively), and pulmonary rehabilitation+active mind body movements therapies versus control for forced vital capacity (0.45; 95 % CI 0.07 to 0.84). Conclusions: active mind body movement therapy programs were the most effective type of exercise program to improve lung function measured by FEV1 and FEV1%; pulmonary rehabilitation+active mind body movements therapies had the greatest effects on FVC in people with COPD. Exercise programs in which the abdominal muscles are strengthened could improve lung emptying, helping to overcome airway resistance in people with COPD. © 2023 Elsevier Masson SASFederación Española de Enfermedades Raras, FEDE
¿Es detectable empíricamente la protección normativa del territorio? Análisis de las tendencias de temperatura y vegetación del área norte de Bogotá con sensores remotos
No full textThis article analyzes the trends in urban development in an area of 6930 hectares in the northern sector of Bogotá that includes the Northern Zonal Management Plan (POZN, in Spanish) and part of the Thomas Van der Hammen Nature Reserve (RTVH, in Spanish). The plan established by the Mayor’s Office through Decree 088 of 2017 seeks to manage an urban development trend that has occurred de facto, with important ecological and social consequences, while the RTVH intends to protect the ecological characteristics of this sector located between the hills and the Bogotá River. The method consisted of analyzing time series of surface temperature and vegetation using remote sensing techniques and radiometric indicators to identify the structural changes experienced by the sector in terms of its biophysical components. The results of the analysis show that the urbanization process taking place in the northern sector of Bogotá is the driver of the observed trends in the biophysical space beyond the legal protection instruments currently in force, including POZN and RTVH. In the case of RTVH, the protection framework has been insufficient to preserve the ecological characteristics that led to its creation. The inclusion of empirical evidence in urban development planning, such as that shown in this work, is key to advancing the active protection of the environment beyond the regulatory discourse. © 2024 Instituto de Geografia. All rights reserved.Universidad Autónoma de Chil
Aula invertida en Pediatría: percepción de estudiantes de Medicina durante la pandemia de Covid-19
No full textFlipped classroom is an innovative teaching and learning methodology, that has demonstrated being effective in the health area. In the context of the actual confinement due to the Covid-19 Pandemic, it perfectly adapts to the new reality of medical teachers and students, as it substitutes face – to – face learning for online tutorials and telepresence meetings.
The present study describes the medicine undergraduate student’s perception, in the Pediatrics course, with respect to inverted classroom classes performed during the COVID-19 Pandemic between June and November 2020. This study involved 93.3% of students enrolled in the university's paediatrics course, the sample consisted of 70 students, with an average age of 22, of whom 30% were men and 70% women, all respondent to the Flipped Classroom Perception Instrument survey. The results showed above 70 % positive perception on all the aspects that were evaluated among them.
A positive perception of the inverted classroom is evidenced by the medical students who took the pediatrics course. It is suggested to perform another after study, to evaluate if this methodology impacts the academic results, compared with traditional learning methodologies. El Aula invertida es un enfoque de enseñanza y aprendizaje innovador que ha demostrado ser efectivo en el área de la salud. En el contexto actual de confinamiento, se adapta sustituyendo la presencialidad por la tutoría en línea o la telepresencialidad. El presente estudio describe la percepción de los estudiantes de pregrado de Medicina de la Universidad de la Sabana de la asignatura de Pediatría, con respecto a las clases dictadas mediante la metodología de Aula invertida con sesiones sincrónicas remotas ante la pandemia por COVID-19, durante el periodo comprendido entre junio y noviembre de 2020. En este estudio participó el 93,3% de los estudiantes matriculados en el curso de pediatría de la Universidad, la muestra estuvo constituida por 70 estudiantes, con un promedio de edad de 22 años, de los cuales 30% eran hombres y 70% mujeres,Instrumento de percepción invertido en el aula. Se identificó una percepción general favorable en cada punto a evaluar, superando siempre el 70% de aceptación entre los estudiantes. Se evidenció una percepción positiva de la metodología del Aula invertida por parte de los estudiantes de medicina que cursaron la asignatura de pediatría. Se sugiere la realización de un estudio a mediano y largo plazo con el fin de evidenciar si esta metodología impacta en los resultados académicos de los estudiantes frente a los métodos de enseñanza tradicional
Unveiling the hydrophilic nature of SDS surfactant through molecular simulations: Exploring the influence of charge distribution on interfacial properties in the vacuum/SDS/water system
No full textThe hydrophilicity of SDS surfactant was evaluated using different charge distributions derived from atomic charges obtained by quantum mechanical calculations. The atomic charges were determined using the Hirshfeld, CM5, CHELPG, and Merz-Kollman methods. The results indicate that the correct charge distribution in the hydrophilic group has an impact on the description of the surfactant hydrophilicity, which allows us to obtain a good estimation of the interfacial properties of the vacuum/SDS/water system. Two models of charge distribution based on the point charge model were proposed for SDS surfactant, using atomic charges computed through Quantum Mechanical calculations. The charge distributions derived from CM5, Merz-Kollman, and CHELPG atomic charges consistently predict the interfacial properties such as: area occupied per molecule, interfacial thicknesses, and radial distribution functions. Using Molecular Dynamics simulations, the ability of the charge distributions combined with nonbonded parameters of the GROMOS53A6 force field to predict the interfacial properties has the following order: CM5 > Merz-Kollman ≈ CHELPG > Hirshfeld. In contrast, the charge distributions overestimated the reduction of the interfacial tension of the vacuum/SDS/water system. Interfacial properties such as interfacial tension, area occupied per SDS molecule, and molecular interaction between the hydrophilic headgroup and water molecules were evaluated. Simulations demonstrated that the high interfacial activity of the SDS surfactant is associated with the high negative charge distribution defined for the hydrophilic headgroup of the surfactant, which enhances the ability to attract water molecules and the solvation of the hydrophilic region. © 2024 Elsevier B.V.Ministry of Economy, Development and Tourism-Chile grant Nuclei on Catalytic Processes towards Sustainable Chemistry; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1231194, 1201880); North Carolina State University, NCSU, (SCR_022168); Anillos de Ciencia y Tecnologia, (ACT210057); China Scholarship Council, CSC, (NCN2021_090, ANID/FONDAP/15110019
Density distributions, magnetic field structures, and fragmentation in high-mass star formation
No full textContext. The fragmentation of high-mass star-forming regions depends on a variety of physical parameters, including density, the magnetic field, and turbulent gas properties. Aims. We evaluate the importance of the density and magnetic field structures in relation to the fragmentation properties during highmass star formation. Methods. Observing the large parsec-scale Stokes I millimeter dust continuum emission with the IRAM 30m telescope and the intermediate-scale (<0.1 pc) polarized submillimeter dust emission with the Submillimeter Array toward a sample of 20 high-mass star-forming regions allows us to quantify the dependence of the fragmentation behavior of these regions on the density and magnetic field structures. Results. Based on the IRAM 30m data, we infer density distributions n ∞ r-p of the regions with typical power-law slopes p around ~1.5. There is no obvious correlation between the power-law slopes of the density structures on larger clump scales (~1 pc) and the number of fragments on smaller core scales (<0.1 pc). Comparing the large-scale single-dish density profiles to those derived earlier from interferometric observations at smaller spatial scales, we find that the smaller-scale power-law slopes are steeper, typically around ~2.0. The flattening toward larger scales is consistent with the star-forming regions being embedded in larger cloud structures that do not decrease in density away from a particular core. The magnetic fields of several regions appear to be aligned with filamentary structures that lead toward the densest central cores. Furthermore, we find different polarization structures; some regions exhibit central polarization holes, whereas other regions show polarized emission also toward the central peak positions. Nevertheless, the polarized intensities are inversely related to the Stokes I intensities, following roughly a power-law slope of ∞ S-0.62I. We estimate magnetic field strengths between ~0.2 and ~4.5 mG, and we find no clear correlation between magnetic field strength and the fragmentation level of the regions. A comparison of the turbulent to magnetic energies shows that they are of roughly equal importance in this sample. The mass-to-flux ratios range between ~2 and ~7, consistent with collapsing star-forming regions. Conclusions. Finding no clear correlations between the present-day large-scale density structure, the magnetic field strength, and the smaller-scale fragmentation properties of the regions, indicates that the fragmentation of high-mass star-forming regions may not be affected strongly by the initial density profiles and magnetic field properties. However, considering the limited evolutionary range and spatial scales of the presented CORE analysis, future research directions should include density structure analysis of younger regions that better resemble the initial conditions, as well as connecting the observed intermediate-scale magnetic field structure with the larger-scale magnetic fields of the parental molecular clouds. © The Authors 2024.CONAHCyT, (86372, MCIN/AEI/10.13039/501100011033, PID2020-117710GB-I00); European Union 'Next GenerationEU; PRTR; Sistema Nacional de Investigadores of CONAHCyT; UNAM-PAPIIT, (IG100223); Smithsonian Institution, SI; European Commission, EC; European Research Council, ERC, (855130); Deutsche Forschungsgemeinschaft, DFG, (KU 2849/9); Academia Sinica, AS, (143-19)Universidad Autónoma de Chil
Two three-electron bonds in two triatomic molecules? The cases of C2O and N2C in their ground states
No full textThe chemical bonding of (Formula presented.) C (Formula presented.) O and (Formula presented.) N (Formula presented.) C is analyzed in this work through the topological quantum approach using the electronic localization function (ELF) at the CASSCF level and by energetic calculations at the CCSD(T) level using four different basis sets. The results show that the dissociation of the molecules occurs via cleavage of the C-C bond in the case of (Formula presented.) C (Formula presented.) O, while in the case of (Formula presented.) N (Formula presented.) C, it occurs via cleavage of the N-C bond. Furthermore, the results obtained with ELF show monosynaptic basins containing excess electrons and disynaptic basins with a low electron population. This leads us to indicate the existence of three-center-two-electron bonds according to previous results. From the valence bond model, a series of resonance structures have been proposed that support our calculations. In addition, the proposed structures have an ionic nature, indicating a charge shift character. © 2023 Wiley Periodicals LLC.Air Force Office of Scientific Research, AFOSR, (FA9550‐19‐1‐0266); Agenția Națională pentru Cercetare și Dezvoltare, ANCD; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1230571); Agencia Nacional de Investigación y Desarrollo, ANI