Influence of Relative Age on Physical Condition and Academic Performance in Adolescents.

Annual age grouping is a common organizational strategy in academics and sports. This strategy could promote the relative effects of age, which refers to the (dis)advantages that subjects who were born in the first or last months of the year may suffer. The consequences could be minimized, resulting in better physical and/or academic results. The objective of the study was to evaluate the influence of the quarter of birth and examine the correlation between physical condition variables and academic performance. The sample included 79 students (51.90% females) 13.46 ± 0.21 years old in the second year of Obligatory Secondary Education. The physical variables of this study were explosive power, cardiorespiratory capacity, speed, flexibility, and muscle strength. They were evaluated using the horizontal jump tests, Cooper test, 50 m sprint, sit-and-reach test, and medicine ball exercises, respectively. The academic variables were obtained from the average academic grade, grouped by key competencies. An Analysis of Covariance (ANCOVA), controlling for gender, body mass, and height, revealed significant differences between male students born in the first quarter compared to those born in subsequent quarters in all physical condition variables (except for cardiorespiratory capacity). For female students, significant differences were observed only in the explosive power variable. No statistically significant intra-sex differences were evident in academic performance at any time of measurement. Additionally, moderate to large correlations were found in the physical condition and academic variables. It is concluded in relation to the need to implement diverse strategies regarding the process of developing physical conditions in adolescence that satisfy the growth needs of students based on age and sex.

Pseudo-Normalization of the T-wave During Stress and Its Relationship With Myocardial Ischemia: Evaluation by Myocardial Perfusion Single Photon Emission Computed Tomography (SPECT).

Background The T-wave alterations are suggestive of ischemia, among them there is the pseudo-normalization (positivization of the T-wave, previously negative, during stress exercise). Myocardial single photon emission computed tomography (SPECT) at rest and stress is usually performed with Technetium 99 (Tc-99), which has high sensitivity and specificity for the detection of ischemic heart disease. In this study, we decided to investigate the patients who pseudo-normalized the T-wave in the stress test to correlate with the existence of ischemia diagnosed by myocardial perfusion study, specifically myocardial SPECT in perfusion and rest with Tc-99. Methodology T - wave pseudo-normalization patients who underwent a myocardial perfusion SPECT between January 2018 and June 2019 were included in this retrospective study. We analyzed 81 patients: 50 patients with pseudo-normalization of T-waves and 31 patients, as a control group, without pseudo-normalization. A descriptive analysis of the quantitative variables was performed using Student's t-test or Mann-Whitney U test, and for the qualitative variables, the χ2 test or Fisher's exact test was performed. Results The degree of ischemia according to the presence or absence of pseudo-normalization of the T-wave. The pseudo-normalization of the T-wave in the group without ischemia (48.4% vs. 36%), for the mild degree the proportions were the same (38.7% vs. 38%), the moderate degree it was slightly higher in the pseudo-normalization of the T-wave (9.7% vs. 18%) and severe (3.2% vs. 6%). Conclusions In this study, the relationship between pseudo-normalization of the T waveform and ischemia, predominantly moderate to severe, was demonstrated. However, it was not statistically significant due to the size of the sample studied.

Association between Adherence to the Mediterranean Diet and Anthropometric and Health Variables in College-Aged Males.

The present study aimed to verify the association between adherence to the Mediterranean diet (MD) and anthropometric and health variables. Four-hundred-and-ninety-five college-aged males aged 18-25 participated in this cross-sectional research. The KIMED (Mediterranean Diet Quality Index for children and adolescents) was used to assess the adherence to MD. The following variables were also assessed: body mass (BM), height (HE), body mass index (BMI), body fat percentage (%FAT), lean mass (LEAN), abdominal girth (AG), waist-to-hip ratio (WHR), oxygen saturation (SPO2), systolic blood pressure (SBP), diastolic blood pressure (DBP), double product (DP), and fasting blood glucose (GLU). The results showed that adherence to MD presented a strong negative correlation with most of the anthropometric parameters (BM: r = -0.571; BMI: r = -0.614; %FAT: r = -0.558; and AG: r = -0.564), a moderate or weak correlation with most of the health variables (GLU: r = -0.407; SBP: r = -0.238; DBP: r = -0.217, and DP: r = -0.265) and LEAN (r = -0.497), and a very weak correlation with WHR (r = -0.090). Many anthropometric parameters (BM, BMI, %FAT, LEAN, AG, WHR) present significant correlations with health variables (SBP, DBP, DP, and GLU). We conclude that greater adherence to Mediterranean diet is associated with healthier values of the selected anthropometric and health parameters. Since most of the anthropometric and health parameters present significant correlations among themselves, this finding could be useful in medical diagnosis, health monitoring, and risk detection. Based on the level of adherence to Mediterranean diet and the KIDMED found in the present study, and considering the prevalence of obesity in the Middle East, it is imperative to implement nutritional interventions with the target population of this research to prevent nutrition-related diseases and promote public health.

Optimization-Based Capacitor Balancing Method with Selective DC Current Ripple Reduction for CHB Converters.

From its introduction to the present day, Cascaded H-Bridge multilevel converters were employed on numerous applications. However, their floating capacitor, while advantageous for some applications (such as photovoltaic) requires the usage of balancing methods by design. Over the years, several such methods were proposed and polished. Some of these methods use optimization techniques or inject a zero-sequence voltage to take advantage of the converter redundancies. This paper describes an optimization-based capacitor balancing method with additional features. It can drive each module DC-Link to a different voltage for independent maximum power point tracking in photovoltaic applications. Moreover, the user can specify the independent active power set points to modules connected to batteries or any other energy storage systems. Finally, DC current ripple can be reduced on some modules, which can extend the lifespan of any connected ultra-capacitors. The method as a whole is tested on real hardware and compared with the state-of-the-art. In its simplest configuration, the presented method shows greater speed, robustness, and current wave quality than the state-of-the-art alternative in spite of producing about 1/3 fewer commutations. Its other characteristics provide additional functionalities and improve the adaptability of the converter to other applications.

Effects of Vest and Sled Resisted Sprint Training on Sprint Performance in Young Soccer Players: A Systematic Review and Meta-analysis.

ABSTRACT: Fernández-Galván, LM, Casado, A, García-Ramos, A, and Haff, GG. Effects of vest and sled resisted sprint training on sprint performance in young soccer players: A systematic review and meta-analysis. J Strength Cond Res 36(7): 2023-2034, 2022-The aim of the meta-analysis was to determine the effect of resisted sprint training (RST) on sprint performance in young (<20 years) soccer players and to analyze whether the training equipment (sled or vest) and magnitude of the resistive load (above or below 20% of body mass [BM]) influences the long-term adaptations in sprint performance. Resisted sprint training reduced the acceleration phase time [standardized mean difference (SMD) = -0.41], with greater reduction in sprint time occurring in response to applying resistance with a vest (SMD = -0.70) when compared with a sled (SMD = -0.27). Similar reductions were determined for resistive loads <20% (SMD = -0.55) and ≥20% of BM (SMD = -0.31). Full sprint time showed a small reduction after RST (SMD = -0.36), regardless of the training equipment (sled: SMD = -0.44; vest: SMD = -0.26) and resistive load (<20% of BM: SMD = -0.40 ≥ 20% of BM: SMD = -0.21). There was a small and nonsignificant reduction in the maximum-velocity phase after RST (SMD = -0.25), which was comparable when the training was performed with vest (SMD = -0.34) or sled (SMD = -0.22). No significant differences in the changes of the acceleration phase time (SMD = 0.05) or full sprint time (SMD = 0.08) were observed between the experimental (sled or vest RST) and control groups (only soccer or unresisted sprint training). In conclusion, RST is effective to improve sprint performance in young soccer players, but the improvements are not superior to unresisted sprint training.

Sprint Performance and Mechanical Force-Velocity Profile among Different Maturational Stages in Young Soccer Players.

The aim of the present study was to determine the influence of maturation status on the components of the sprint force-velocity (F-V) profile in young soccer players. Sixty-two young male soccer players from the same professional soccer academy took part in the present study. A cross-sectional design was implemented to compare the main components of the sprint F-V profile (i.e., maximal theoretical force (F0), velocity (V0), power (Pmax), and ratio of horizontal-to-resultant force (RFpeak), and decrease in the ratio of horizontal-to-resultant force (DRF)) and sprint performance (5, 20, and 30 m sprint time) among participants' maturation stages (i.e., pre-, mid- and post-peak height velocity (PHV) groups). The results show that the ES of differences in 5 min sprint performance, F0, and RFpeak (i.e., strength- and acceleration-related components of the sprint F-V profile) were greater between pre- and mid-PHV groups than those between mid- and post-PHV groups (i.e., large and very large effects (1.24 ≤ ES ≤ 2.42) vs. moderate, small, and zero effects (0 ≤ ES ≤ 0.69), respectively). However, the ES of differences in V0 and DRF (i.e., peak speed-related components of the sprint F-V profile) were greater between mid- and post-PHV groups than those between pre- and mid-PHV groups (i.e., large effects (1.54 ≤ ES ≤ 1.92) vs. moderate effects (-0.59 ≤ ES ≤ 1), respectively). Once the strength development is achieved to a great extent from the pre- to mid-PHV groups, specific strength training methods may be used for young soccer players to improve their sprint performance.

The Post-Activation Potentiation Effects on Sprinting Abilities in Junior Tennis Players.

OBJECTIVE: This study aimed to compare the acute effects of a full squat (SQ) or hip thrust (HT) with two different loading intensities (60% and 85% 1 RM) on sprint ability in junior male tennis players. METHODS: Nineteen tennis players were included in this research. They underwent four different experimental conditions: HT at 60% 1 RM, HT at 85% 1 RM, SQ at 60% 1 RM, or SQ at 85%. The force-velocity (F-V) profile was used to assess tennis players' sprint acceleration ability before and after applying the conditioning stimulus. The variables registered were as follows: 5 m test (5 m), 10 m test (10 m), maximum theoretical force (F0), maximum power (Pmax), and the maximal ratio of horizontal-to-resultant force (RFpeak). RESULTS: Significant improvements in 5 m, Pmax, and RFpeak were observed when the conditioning stimulus was performing one set of seven reps of HT at 60% 1 RM. When the activation protocol was one set of seven reps of SQ at 60% 1 RM, significant improvements in 5 m, 10 m, F0, Pmax (N), and RFpeak were detected. Additionally, performing one set of three reps of SQ at 85% 1 RM as an activation protocol provided significant improvements in F0. Conclusion: The use of HT and SQ with a load of 60% 1 RM improved the sprint F-V profile components related to the acceleration phase of the sprint in junior tennis players. Using intensity loads of 85% 1 RM is not adequate to increase acute sprint performance in this population. HT presents a higher transferability to sprinting in the first 5 m of sprinting, whereas SQ provides acute improvements in different sprinting phases.

Epidemiology of Sports-Related Injuries and Associated Risk Factors in Adolescent Athletes: An Injury Surveillance.

The present study aimed to determine the epidemiology of sport-related injuries in amateur and professional adolescent athletes and the incidence of different risk factors on those injuries. Four hundred ninety-eight athletes aged 14 to 21 voluntarily participated in this prospective injury surveillance, conducted from 1 January 2019 to 31 December 2019. The information collected included: personal data, sports aspects, characteristics of the injuries, and lifestyle. Forty point four percent of the participants suffered an injury in 2019 (39% of them in a previously injured area). The average injury rate was 2.64 per 1000 h. Soccer presented the highest rate (7.21). The most common injuries were: lumbar muscle strains (12.24%), ankle sprains (11.98%), and bone fractures (9.31%). Ankles (36.12%), knees (19.32%), and shoulders (6.47%) concentrated the highest number of injuries. Fifty-nine point twenty-eight percent of the injuries occurred during practices, and 40.72% during competition or peri-competition. Higher injury rates were associated (in this order) with the following factors: (a) Greater number of hours of practice per week. (b) Not performing warm-ups. (c) Using inadequate sports facilities. (d) Being aged 14-17. (e) Not performing physical preparation. (f) Inappropriate training load. (g) Not performing injury-preventive activities. (h) Performing sports technique without the supervision of one sports coach. (i) Inadequate sports equipment. In conclusion, since most injury risk factors are modifiable, it is imperative to implement strategies to reduce amateur and professional adolescent athletes' injury rates.

Examination of the Sprinting and Jumping Force-Velocity Profiles in Young Soccer Players at Different Maturational Stages.

The aim was to determine the relationships among components of the force-velocity (F-V) profiles in jumping and sprinting, with both biological and chronological ages in 89 young soccer players belonging to categories from U10 to U18. Participants performed countermovement jumps (CMJ) and 20-m sprint tests. F-V components assessed were associated with both maturity offset and chronological age, using correlation and multiple linear regression analyses. Horizontal (i.e., maximal theoretical force [F0] and velocity [V0], maximal power [Pmax] and F-V slope) and vertical (i.e., [F0] and [Pmax]) F-V components displayed very large correlations (i.e., 0.79 ≤ r ≤ 0.92) with both chronological age and maturity offset. The combination of sprinting Pmax and training experience and jumping F0 and training experience explained up to 94% of the variances in maturity offset and chronological age. Furthermore, similar correlations were found between sprinting and jumping performances, and components of the F-V profiles, and both maturity offset and chronological age. Identification of vertical jump and sprint mechanical determinants may assist in strengthening those components of the F-V profile which are weaker throughout the training process. Sprinting and jumping capabilities can be indistinctly monitored with respect to their chronological age or maturity offset in young soccer players.

Hemodynamic profiles related to circulatory shock in cardiac care units / Perfiles hemodinámicos relacionados con el choque circulatorio en unidades de cuidados cardiacos

Abstract One-third of the population in intensive care units is in a state of circulatory shock, whose rapid recognition and mechanism differentiation are of great importance. The clinical context and physical examination are of great value, but in complex situations as in cardiac care units, it is mandatory the use of advanced hemodynamic monitorization devices, both to determine the main mechanism of shock, as to decide management and guide response to treatment, these devices include pulmonary flotation catheter as the gold standard, as well as more recent techniques including echocardiography and pulmonary ultrasound, among others. This article emphasizes the different shock mechanisms observed in the cardiac care units, with a proposal for approach and treatment.

Resumen Un tercio de la población de pacientes en unidades de cuidados intensivos se encuentran en choque circulatorio, el identificarlo y determinar su mecanismo de manera rápida y eficaz es de gran importancia. El contexto clínico y el examen físico son de gran utilidad, sin embargo existen situaciones de alta complejidad en las que se requiere del uso de las distintas modalidades de monitorización hemodinámica avanzada, tanto para determinar la causa, como para decidir el manejo y guiar respuesta al tratamiento, incluyendo el catéter de flotación pulmonar como gold standard, así como técnicas más recientes incluyendo ecocardiografía y ultrasonido pulmonar, entre otros. Este artículo enfatiza los distintos mecanismos de choque observados en las unidades de cuidados cardiacos, con propuesta de abordaje y tratamiento.

Hemodynamic profiles related to circulatory shock in cardiac care units.

One-third of the population in intensive care units is in a state of circulatory shock, whose rapid recognition and mechanism differentiation are of great importance. The clinical context and physical examination are of great value, but in complex situations as in cardiac care units, it is mandatory the use of advanced hemodynamic monitorization devices, both to determine the main mechanism of shock, as to decide management and guide response to treatment, these devices include pulmonary flotation catheter as the gold standard, as well as more recent techniques including echocardiography and pulmonary ultrasound, among others. This article emphasizes the different shock mechanisms observed in the cardiac care units, with a proposal for approach and treatment.

Un tercio de la población de pacientes en unidades de cuidados intensivos se encuentran en choque circulatorio, el identificarlo y determinar su mecanismo de manera rápida y eficaz es de gran importancia. El contexto clínico y el examen físico son de gran utilidad, sin embargo existen situaciones de alta complejidad en las que se requiere del uso de las distintas modalidades de monitorización hemodinámica avanzada, tanto para determinar la causa, como para decidir el manejo y guiar respuesta al tratamiento, incluyendo el catéter de flotación pulmonar como gold standard, así como técnicas más recientes incluyendo ecocardiografía y ultrasonido pulmonar, entre otros. Este artículo enfatiza los distintos mecanismos de choque observados en las unidades de cuidados cardiacos, con propuesta de abordaje y tratamiento.

Síndrome de la vena cava superior: diagnóstico y tratamiento / Superior vena cava syndrome: Diagnosis and treatment

Resumen: El síndrome de la vena cava superior es un conjunto de signos y síntomas desencadenados por la obstrucción de la vena cava superior. Los tumores intratorácicos malignos son la principal causa. Sin embargo, en las últimas décadas se han descrito causas benignas, como la trombosis asociada con la colocación de accesos venosos.

Abstract: Superior vena cava syndrome is a set of signs and symptoms due to superior vena cava obstruction. Intratoracic malignant tumors are the main cause. However, in last decades benign causes such as thrombosis related to venous access colocation have been described.

Increased Wildfire Risk Driven by Climate and Development Interactions in the Bolivian Chiquitania, Southern Amazonia.

Wildfires are becoming increasingly dominant in tropical landscapes due to reinforcing feedbacks between land cover change and more severe dry conditions. This study focused on the Bolivian Chiquitania, a region located at the southern edge of Amazonia. The extensive, unique and well-conserved tropical dry forest in this region is susceptible to wildfires due to a marked seasonality. We used a novel approach to assess fire risk at the regional level driven by different development trajectories interacting with changing climatic conditions. Possible future risk scenarios were simulated using maximum entropy modelling with presence-only data, combining land cover, anthropogenic and climatic variables. We found that important determinants of fire risk in the region are distance to roads, recent deforestation and density of human settlements. Severely dry conditions alone increased the area of high fire risk by 69%, affecting all categories of land use and land cover. Interactions between extreme dry conditions and rapid frontier expansion further increased fire risk, resulting in potential biomass loss of 2.44±0.8 Tg in high risk area, about 1.8 times higher than the estimates for the 2010 drought. These interactions showed particularly high fire risk in land used for 'extensive cattle ranching', 'agro-silvopastoral use' and 'intensive cattle ranching and agriculture'. These findings have serious implications for subsistence activities and the economy in the Chiquitania, which greatly depend on the forestry, agriculture and livestock sectors. Results are particularly concerning if considering the current development policies promoting frontier expansion. Departmental protected areas inhibited wildfires when strategically established in areas of high risk, even under drought conditions. However, further research is needed to assess their effectiveness accounting for more specific contextual factors. This novel and simple modelling approach can inform fire and land management decisions in the Chiquitania and other tropical forest landscapes to better anticipate and manage large wildfires in the future.

Secreto profesional en el ejercicio de la odontología / Professional secrecy in the practice of dentistry

El concepto de secreto profesional existe desde época antigua, y es una práctica que rige desde el célebre "Juramento Hipocrático", en virtud al cual el médico recién egresado, da su palabra de guardar reserva sobre los hechos que conozca en el ejercicio de su ciencia y arte. Los profesionales de la salud, como los odontólogos acceden a través de la anamnesis, examen clínico y estudios auxiliares al conocimiento de datos y circunstancias que adquieren en carácter confidencial, y están obligados a mantenerlos con el más absoluto sigilo. Es revisión tiene como objetivo definir el secreto profesional, el cual se establece como un derecho y obligación de los odontólogos y que beneficia a la odontología, al odontólogo y al paciente; así como dar a conocer las normas jurídicas que regulan el secreto profesional en el ejercicio de la odontología en nuestro país. La intimidad es un valor ético y jurídico amparado por la Constitución Nacional y por la legislación vigente en nuestro país, y como tal hay que demandarlo y protegerlo, es por tal razón que con acierto se establece preservar los datos, informaciones y todo aquello relacionado al paciente, a lo que el odontólogo tenga acceso en el ejercicio de la profesión, favoreciendo la confianza hacia la los actos odontólogos, de manera a no desvirtuar, sino elevar la mística relación odontólogo paciente.