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BACKGROUND: Airway injuries are reported among preterm infants with bronchopulmonary dysplasia. We hypothesized that prolonged ventilation in preterm infants is associated with subglottic dilatation that can be reliably evaluated by point of care ultrasonography (POCUS). METHODS: All preterm infants (<29-weeks) admitted to the neonatal ICU at the Advent-Health from January-2020 to June-2022 were eligible if they required invasive ventilation for ≤7 days in the first 28 days of life (control) or remained intubated for ≥28 days (prolonged ventilation). Sonography was performed by one technician and all images were reviewed by the pediatric radiologist. The trachea size was measured 3 times by randomly selecting three images. The first 20 scans were also independently reported by a different pediatric radiologist. Intra and inter-observer variability was estimated. Mean trachea size and weight at the time of imaging were compared. RESULTS: Out of 417 eligible infants; 11 died before 28 days and 163 required ventilation for 8-27 days. Consent missed for 80 infants during COVID-19 pandemic. We enrolled 23 and 28 infants in the control & prolonged ventilation groups, respectively. Inter and intra-observer correlations were 0.83 and 0.97 respectively. Infants in the control group had higher gestation and birth weight. Infants on prolonged ventilation were at higher risk for infections, BPD, longer hospital stay and significant subglottic dilation (4.51 ± 0.04 vs 4.17 ± 0.02 mm, p < 0.01) despite smaller body weight at the time of imaging (884 ± 102 vs 1059 ± 123g, p < 0.01). CONCLUSION: Extremely preterm infants on prolonged ventilation are at risk for sub-glottic dilatation that can be reliably measured by POCUS.
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Displasia Broncopulmonar , Lactente Extremamente Prematuro , Respiração Artificial , Traqueia , Ultrassonografia , Humanos , Recém-Nascido , Respiração Artificial/efeitos adversos , Respiração Artificial/métodos , Masculino , Feminino , Traqueia/diagnóstico por imagem , Displasia Broncopulmonar/diagnóstico por imagem , Displasia Broncopulmonar/etiologia , Ultrassonografia/métodos , Dilatação Patológica/diagnóstico por imagem , Glote/diagnóstico por imagem , COVID-19/complicações , Fatores de TempoRESUMO
Morphofunctional assessment was developed to evaluate disease-related malnutrition. However, it can also be used to assess cardiometabolic risk, as excess adiposity increases this risk. Phenylketonuria (PKU) is the most prevalent inherited metabolic disease among adults, and obesity in PKU has recently gained interest, although fat mass correlates better with cardiometabolic risk than body mass index. In this systematic review, the objective was to assess whether adult patients with PKU have higher fat mass than healthy controls. Studies of adult PKU patients undergoing dietary treatment in a metabolic clinic reporting fat mass were included. The PubMed and EMBASE databases were searched. Relevance of articles, data collection, and risk of bias were evaluated by two independent reviewers. Ten articles were evaluated, six with a control group, including 310 subjects with PKU, 62 with mild hyperphenylalaninemia, and 157 controls. One study reported a significant and four a tendency towards an increased fat mass in all patients or only females with PKU. Limitations included not having a healthy control group, not reporting sex-specific results and using different techniques to assess fat mass. Evaluation of fat mass should be included in the morphofunctional assessment of cardiometabolic risk in adult patients with PKU.
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Fenilcetonúrias , Humanos , Fenilcetonúrias/complicações , Fenilcetonúrias/dietoterapia , Fenilcetonúrias/fisiopatologia , Adulto , Feminino , Masculino , Desnutrição/diagnóstico , Adiposidade , Índice de Massa Corporal , Obesidade/complicações , Fatores de Risco Cardiometabólico , Tecido AdiposoRESUMO
Islands are biodiversity hotspots that host unique assemblages. However, a substantial proportion of island species are threatened and their long-term survival is uncertain. Identifying and preserving vulnerable species has become a priority, but it is also essential to combine this information with other facets of biodiversity like functional diversity, to understand how future extinctions might affect ecosystem stability and functioning. Focusing on mammals, we (i) assessed how much functional space would be lost if threatened species go extinct, (ii) determined the minimum number of extinctions that would cause a significant functional loss, (iii) identified the characteristics (e.g., biotic, climatic, geographic, or orographic) of the islands most vulnerable to future changes in the functional space, and (iv) quantified how much of that potential functional loss would be offset by introduced species. Using trait information for 1474 mammal species occurring in 318 islands worldwide, we built trait probability density functions to quantify changes in functional richness and functional redundancy in each island if the mammals categorized by IUCN as threatened disappeared. We found that the extinction of threatened mammals would reduce the functional space in 63% of the assessed islands, although these extinctions in general would cause a reduction of less than 15% of their overall functional space. Also, on most islands, the extinction of just a few species would be sufficient to cause a significant loss of functional diversity. The potential functional loss would be higher on small, isolated, and/or species-rich islands, and, in general, the functional space lost would not be offset by introduced species. Our results show that the preservation of native species and their ecological roles remains crucial for maintaining the current functioning of island ecosystems. Therefore, conservation measures considering functional diversity are imperative to safeguard the unique functional roles of threatened mammal species on islands.
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Biodiversidade , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Extinção Biológica , Ilhas , Mamíferos , Animais , Mamíferos/fisiologia , Espécies IntroduzidasRESUMO
The popularity of surfing has increased exponentially, reaching its recent debut in the Olympic Games. However, surfing suffers from a relative immature technological market, while in other sports some technologies such as global navigation satellite systems (GNSSs) have become an essential work material for strength and conditioning and head coaches. This article aims to systematically review surfers' time-motion demands based on GNSSs. A systematic review of relevant articles was carried out using five main databases (PubMed, ProQuest Central, SCOPUS, SPORTDiscus, and FECYT (Web of Sciences, CCC, CIDW, KJD, MEDLINE, RSCI, and SCIELO)) until 23 March 2024. From the 238 studies initially found, 9 were included in the qualitative synthesis. In these, GNSS devices were employed with male (n = 143) and female (n = 28) surfers from different levels during competition and training situations. The studies show that the intermittent nature of the sport is evident, with substantial periods spent paddling and waiting punctuated by relatively brief high-intensity efforts when riding waves at high speeds. Notable differences emerged between competition and training demands, suggesting potential mismatches in how athletes currently prepare compared to event requirements. These novel insights allow quantifying surfing's harsh physiological requirements and could guide conditioning practices to better meet the sport's unique characteristics across populations. Therefore, training should emulate the lengthy aerobic capabilities needed for the paddling volumes observed, while also targeting the anaerobic systems to meet the repeated high-intensity surf riding efforts. However, inconsistencies in methods and reporting practices limit direct comparisons and comprehensive profiling of the sport's physical characteristics.
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Sistemas de Informação Geográfica , Humanos , Estudos de Tempo e Movimento , Feminino , Masculino , Desempenho Atlético/fisiologia , Atletas , Esportes Aquáticos/fisiologia , Esportes/fisiologiaRESUMO
Early childhood is a critical period for physical and motor development with implications for long-term health. This systematic review examined the relationship between anthropometric characteristics and measures of physical fitness and motor skills in preschool-aged children (typically 2-6 years). The search strategy was applied in four databases (PubMed, ProQuest Central, Scopus, and Web of Science) to find articles published before 11 April 2024. The results consistently demonstrated significant associations between anthropometric variables (height, weight, body mass index [BMI], body composition) and physical performance measures. Notably, height and mass were often better predictors of fitness status than BMI alone. Indicators of undernutrition (stunting, wasting) were negatively associated with motor development, emphasizing the importance of adequate nutrition. While some studies reported impaired fitness and motor skills among overweight/obese preschoolers compared to normal-weight peers, others found no differences based on weight status. Relationships between physical activity levels, anthropometrics, and motor outcomes were complex and inconsistent across studies. This review highlights key findings regarding the influence of anthropometric factors on physical capabilities in early childhood. Early identification of children with impaired growth or excessive adiposity may inform tailored interventions to promote optimal motor development and prevent issues like obesity. Creating supportive environments for healthy growth and age-appropriate physical activity opportunities is crucial during this critical developmental window.
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Beach variants of popular sports like soccer and handball have grown in participation over the last decade. However, the characterization of the workload demands in beach sports remains limited compared to their indoor equivalents. This systematic review aimed to: (1) characterize internal and external loads during beach invasion sports match-play; (2) identify technologies and metrics used for monitoring; (3) compare the demands of indoor sports; and (4) explore differences by competition level, age, sex, and beach sport. Fifteen studies ultimately met the inclusion criteria. The locomotive volumes averaged 929 ± 269 m (average) and 16.5 ± 3.3 km/h (peak) alongside 368 ± 103 accelerations and 8 ± 4 jumps per session. The impacts approached 700 per session. The heart rates reached 166-192 beats per minute (maximal) eliciting 60-95% intensity. The player load was 12.5 ± 2.9 to 125 ± 30 units. Males showed 10-15% higher external but equivalent internal loads versus females. Earlier studies relied solely on a time-motion analysis, while recent works integrate electronic performance and tracking systems, enabling a more holistic quantification. However, substantial metric intensity zone variability persists. Beach sports entail intermittent high-intensity activity with a lower-intensity recovery. Unstable surface likely explains the heightened internal strain despite moderately lower running volumes than indoor sports. The continued integration of technology together with the standardization of workload intensity zones is needed to inform a beach-specific training prescription.
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Esportes , Humanos , Masculino , Feminino , Esportes/fisiologia , Frequência Cardíaca/fisiologia , Desempenho Atlético/fisiologia , PraiasRESUMO
Basketball involves frequent high-intensity movements requiring optimal aerobic power. Altitude training can enhance physiological adaptations, but research examining its effects in basketball is limited. This study aimed to characterize the internal/external workload of professional basketball players during preseason and evaluate the effects of altitude and playing position. Twelve top-tier professional male basketball players (Liga Endesa, ACB; guards: n = 3, forwards: n = 5, and centers: n = 4) participated in a crossover study design composed of two training camps with nine sessions over 6 days under two different conditions: high altitude (2320 m) and sea level (10 m). Internal loads (heart rate, %HRMAX) and external loads (total distances covered across speed thresholds, accelerations/decelerations, impacts, and jumps) were quantified via wearable tracking and heart rate telemetry. Repeated-measures MANOVA tested the altitude x playing position effects. Altitude increased the total distance (+10%), lower-speed running distances (+10-39%), accelerations/decelerations (+25-30%), average heart rate (+6%), time in higher-intensity HR zones (+23-63%), and jumps (+13%) across all positions (p < 0.05). Positional differences existed, with guards accruing more high-speed running and centers exhibiting greater cardiovascular demands (p < 0.05). In conclusion, a 6-day altitude block effectively overloads training, providing a stimulus to enhance fitness capacities when structured appropriately. Monitoring workloads and individualizing training by playing position are important when implementing altitude training, given the varied responses.
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Altitude , Basquetebol , Frequência Cardíaca , Carga de Trabalho , Humanos , Basquetebol/fisiologia , Masculino , Frequência Cardíaca/fisiologia , Adulto , Adulto Jovem , Estudos Cross-Over , Desempenho Atlético/fisiologia , Aceleração , Corrida/fisiologia , AtletasRESUMO
The study aimed to calculate training intensity and load using muscle oxygen saturation (SmO2) during two differentiated physical tasks. 29 university athletes participated in a 40-m Maximal Shuttle Run Test (MST, 10 × 40-m with 30 s recovery between sprints) and a 3000-m time trial run. Distance and time were used to calculate external load (EL). Internal load indicators were calculated based on percentage of maximum heart rate (%HRMAX) and SmO2 variables: muscle oxygen extraction (∇%SmO2) and the cardio-muscle oxygen index (CMOI) was also provided by relating ∇%SmO2 ÷ %HRMAX, and the training load were calculated as the product of speed (m/min × IL) and the efficiency index [Effindex (m/min ÷ IL)]. A student t test was applied based on Bayesian factor analysis. As expected, EL differed in the 40-m MST (331 ± 22.8) vs. 3000-m trials (222 ± 56.8) [BF10 = 6.25e+6; p = <0.001]. Likewise, IL showed higher values in 40-m MST (39.20 ± 15.44) vs. 3000-m (30.51 ± 8.67) in CMOI: [BF10 = 1.70; p = 0.039]. Training load was greater in 40-m MST (85.77 ± 27.40) vs. 3000-m (15.55 ± 6.77) [(m/min × ∇%SmO2): BF10 = 12.5; p = 0.003] and 40-m MST (129.27 ± 49.44) vs. 3000-m (70.63 ± 32.98) [(m/min × CMOI): BF10 = 169.6; p = <0.001]. Also, the Effindex was higher in 40-m MST (10.19 ± 4.17) vs. 3000-m (6.06 ± 2.21) [(m/min × ∇%SmO2): BF10 = 137.03; p = <0.001] and 40-m MST (9.69 ± 4.11) vs. 3000-m (7.55 ± 1.87) [(m/min × CMOI): BF10 = 1.86; p = 0.035]. This study demonstrates calculations of training intensity and load based on SmO2 as an internal load indicator along with speed as an external load indicator during two differentiated exercises.
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Differences within species (Intraspecific trait variation - ITV) contribute substantially to overall trait variability and environmental harshness can reduce among-species variation. While aboveground traits have received considerable attention, knowledge about ITV in fine-root traits and how it differs from ITV in aboveground traits remains limited. This study examined the partitioning of trait variation aboveground and fine-root traits in 52 European herbaceous species and how such proportions change in response to drought, offering valuable insights for accurate functional species characterization and inter-species comparisons. We studied seven morphological aboveground and fine-root traits under drought and well-watered conditions in a greenhouse experiment. Linear mixed effect models and permutational multivariate analysis of variance (PERMANOVA) were employed to decompose trait variation, ensuring the robustness of our results. We also calculated variance partitioning for the combination of aboveground traits and the combination of fine-root traits, as well as pairs of analogous leaf and fine-root traits (i.e., traits that fulfill similar functions) for each treatment (control and drought). Among-species trait differences explained a greater proportion of overall variance than within-species variation, except for root dry matter content (RDMC). Height and leaf area stood out, with species' identity accounting for 87-90% of total trait variation. Drought had no significant effect on the proportions of variation in any of the traits. However, the combination of fine-root traits exhibited higher intraspecific variability (44-44%) than aboveground traits (19-21%) under both drought and control. Analogous root traits also showed higher ITV (51-50%) than analogous leaf traits (27-31%). Our findings highlight substantial within-species variation and the nuanced responses of fine-root traits, particularly RDMC, suggesting root traits' flexibility to soil heterogeneity that fosters less differentiation among species. Among-species trait differences, especially aboveground, may underscore distinct strategies and competitive abilities for resource acquisition and utilization. This study contributes to elucidate the mechanisms underlying the multifunctionality of the above- and belowground plants compartments.
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Theory suggests that intraspecific trait variability may promote species coexistence when competitively inferior species have higher intraspecific trait variability than their superior competitors. Here, we provide empirical evidence for this phenomenon in tree seedlings. We evaluated intraspecific variability and plastic response of ten traits in 6750 seedlings of ten species in a three-year greenhouse experiment. While we observed no relationship between intraspecific trait variability and species competitiveness in competition-free homogeneous environments, an inverse relationship emerged under interspecific competition and in spatially heterogeneous environments. We showed that this relationship is driven by the plastic response of the competitively inferior species: Compared to their competitively superior counterparts, they exhibited a greater increase in trait variability, particularly in fine-root traits, in response to competition, environmental heterogeneity and their combination. Our findings contribute to understanding how interspecific competition and intraspecific trait variability together structure plant communities.
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Plantas , Plântula , Fenótipo , ÁrvoresRESUMO
The unprecedented COVID-19 health crisis severely disrupted global sports in 2020, prompting lengthy suspensions followed by resumed competitions under abnormal behind-closed-doors conditions without fans. These disruptions necessitated tactical adaptations by coaches and teams, attempting to still achieve successful outcomes. This study investigates the pandemic's impacts on performance metrics and indicators within Spanish professional soccer. Utilizing systematic notational analysis, 760 match cases from the 2019-2020 La Liga season were examined, comprising 27 matchdays from the pre-COVID context and 11 after resumption. Multivariate tests identified significant pre/post differences and interactions for various technical indicators including shots, cards, corners, and offside calls. The pandemic was associated with a reduction from 12 to just 5 identifiable playing styles, suggestive of increased conservatism featuring more passive play, limited attacking depth, and horizontal ball movement. Such tactical changes appear provoked by condensed fixture scheduling post-lockdown, the lack of supportive crowds, and compromised player fitness/recovery. By quantifying these COVID-precipitated changes, the analysis provides tangible evidence for coaches to make informed adjustments in training and preparation for functioning effectively in disrupted environments. The findings emphasize that versatility and flexibility will be vital to optimize performance during times of unprecedented uncertainty.
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Currently, basketball teams use inertial devices for monitoring external and internal workload demands during training and competitions. However, the intensity thresholds preset by device manufacturers are generic and not adapted for specific sports (e.g., basketball) and players' positions (e.g., guards, forwards, and centers). Using universal intensity thresholds may lead to failure in accurately capturing the true external load faced by players in different positions. Therefore, the present study aimed to identify external load demands based on playing positions and establish different intensity thresholds based on match demands in order to have specific reference values for teams belonging to the highest competitive level of Spanish basketball. Professional male players (n = 68) from the Spanish ACB league were monitored during preseason official games. Three specific positions were used to group the players: guards, forwards, and centers. Speed, accelerations, decelerations, impacts/min, and player load/min were collected via inertial devices. Two-step clustering and k-means clustering categorized load metrics into intensity zones for guards, forwards, and centers. Guards covered more distance at high speeds (12.72-17.50 km/h) than forwards and centers (p < 0.001). Centers experienced the most impacts/min (p < 0.001). Guards exhibited greater accelerations/decelerations, albeit mostly low magnitude (p < 0.001). K-means clustering allowed the setting of five zones revealing additional thresholds. All positions showed differences in threshold values (p < 0.001). The findings provide insights into potential disparities in the external load during competition and help establish position-specific intensity thresholds for optimal monitoring in basketball. These data are highly applicable to the design of training tasks at the highest competitive level.
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Desempenho Atlético , Basquetebol , Masculino , Humanos , Carga de Trabalho , AceleraçãoRESUMO
Human activities have altered the species composition of assemblages through introductions and extinctions, but it remains unclear how those changes can affect the different facets of biodiversity. Here we assessed the impact of changes in species composition on taxonomic, functional, and phylogenetic diversity across 281 bird assemblages worldwide. To provide a more nuanced understanding of functional diversity, we distinguished morphological from life-history traits. We showed that shifts in species composition could trigger a global decline in avian biodiversity due to the high number of potential extinctions. Moreover, these extinctions were not random but unique in terms of function and phylogeny at the regional level. Our findings demonstrated that non-native species cannot compensate for these losses, as they are both morphologically and phylogenetically close to the native fauna. In the context of the ongoing biodiversity crisis, such alterations in the functional and phylogenetic structure of bird assemblages could heighten ecosystem vulnerability.
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Ecossistema , Espécies em Perigo de Extinção , Animais , Humanos , Filogenia , Biodiversidade , AvesRESUMO
The Kunming-Montreal Global Biodiversity Framework of the Convention on Biological Diversity calls for an expansion of the current protected areas (PAs) to cover at least 30% of global land and water areas by 2030 (i.e., the 30×30 target). Efficient spatial planning for PA expansion is an urgent need for global conservation practice. A spatial prioritization framework considering multiple dimensions of biodiversity is critical for improving the efficiency of the spatial planning of PAs, yet it remains a challenge. We developed an index for the identification of priority areas based on functionally rare, evolutionarily distinct, and globally endangered species (FREDGE) and applied it to 21,536 terrestrial vertebrates. We determined species distributions, conservation status (global endangerment), molecular phylogenies (evolutionary distinctiveness), and life-history traits (functional rarity). Madagascar, Central America, and the Andes were of high priority for the conservation of multiple dimensions of terrestrial vertebrate biodiversity. However, 68.8% of grid cells in these priority areas had <17% of their area covered by PAs, and these priority areas were under intense anthropogenic and climate change threats. These results highlight the difficulties of conserving multiple dimensions of biodiversity. Our global analyses of the geographical patterns of multiple dimensions of terrestrial vertebrate biodiversity demonstrate the insufficiency of the conservation of different biodiversity dimensions, and our index, based on multiple dimensions of biodiversity, provides a useful tool for guiding future spatial prioritization of PA expansion to achieve the 30×30 target under serious pressures.
+Identificación de las prioridades mundiales de conservación para los vertebrados terrestres con base en varias dimensiones de la biodiversidad Resumen El Marco Mundial de Biodiversidad de Kunming-Montreal del Convenio sobre Diversidad Biológica demanda la expansión de las áreas protegidas actuales (AP) para que cubran al menos el 30% de las áreas marinas y terrestres para el 2030 (el objetivo 30×30). La conservación mundial necesita con urgencia de la planeación espacial eficiente para que la expansión de las AP. Es importante tener un marco de priorización espacial que considere varias dimensiones de la biodiversidad para mejorar la eficiencia de la planeación espacial de las AP, sin embargo, esto todavía es un reto. Desarrollamos un índice para identificar las áreas prioritarias con base en las especies funcionalmente raras, evolutivamente distintas y en peligro mundial (FREDGE, en inglés). Aplicamos este índice a 21,536 especies de vertebrados terrestres y determinamos su distribución, estado de conservación (peligro mundial), filogenia molecular (singularidad evolutiva) y características de la historia de vida (rareza funcional). Madagascar, América Central y los Andes representaron una gran prioridad para la conservación de varias dimensiones de la biodiversidad de vertebrados terrestres. Sin embargo, el 68.8% de las celdas de la cuadrícula en estas áreas prioritarias tuvieron <17% de su área cubierta por AP, y estas áreas prioritarias estaban sometidas a amenazas intensas de origen antropogénicas y de cambio climático. Estos resultados resaltan las dificultades de conservar las diferentes dimensiones de la biodiversidad. Nuestro análisis mundial de los patrones geográficos de las diferentes dimensiones de la biodiversidad de vertebrados terrestres demuestra la insuficiencia de la conservación de diferentes dimensiones de la biodiversidad y nuestro índice basado en varias dimensiones de la biodiversidad proporciona una herramienta útil para orientar en el futuro la priorización espacial de la expansión de AP para lograr el objetivo 30×30 bajo presión severa.
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Abstract Introduction Academic performance in medical students can be influenced by several factors, including those related to mental health and family relationships. Objective To examine the factors affecting academic performance in medical students, specifically considering potential diagnoses of depression. Method A survey was conducted among 747 fourth-year medical students. The survey included questions on sociodemographic variables, mental health, and well-being. The Patient Health Questionnaire (PHQ) was utilized, encompassing sections on depression, anxiety, panic, eating habits, alcohol consumption, and the Stress Perception Scale. Academic performance was assessed based on students' Grade Point Average (GPA). Descriptive statistics, Pearson correlation coefficients, and a linear regression model were employed for data analysis. Results The study revealed several variables significantly associated with GPA. Age (r = -.388), financial situation (r = .241), relationships with cohabitants (r = .165), and relationships with peers (r = .217) were found to have a correlation with academic performance. Additionally, repeating a course was found to be significantly associated with a person's GPA (r = .518) even after controlling for depression. Discussion and conclusion The findings indicate that robust mental health, a favorable financial situation, and positive interpersonal relationships are crucial for achieving optimal academic performance in medical students. These results emphasize the need to address mental health concerns, promote a supportive social environment, and provide financial assistance to enhance the educational outcomes of medical students.
Resumen Introducción El desempeño académico de los estudiantes de medicina puede verse influenciado por varios factores, entre ellos los relacionados con la salud mental y las relaciones familiares. Objetivo Examinar los factores que afectan el desempeño académico en estudiantes de medicina, considerando específicamente los posibles diagnósticos de depresión. Método Se realizó una encuesta entre 747 estudiantes de cuarto año de la carrera de medicina. La encuesta incluyó preguntas sobre variables sociodemográficas, salud mental y bienestar. Se utilizó el Cuestionario de Salud del Paciente (PHQ), que comprende secciones sobre depresión, ansiedad, pánico, hábitos alimentarios, consumo de alcohol y la Escala de Percepción del Estrés. El desempeño académico se evaluó con base en el promedio de calificaciones (GPA) de los estudiantes. Se emplearon estadísticas descriptivas, coeficientes de correlación de Pearson y un modelo de regresión lineal para el análisis de datos. Resultados El estudio reveló varias variables significativamente asociadas con el GPA. Se encontró que la edad (r = -.388), la situación financiera (r = .241), las relaciones con los convivientes (r = .165) y las relaciones con los compañeros (r = .217) tenían correlación con el rendimiento académico. Además, se encontró que repetir un curso estaba significativamente asociado con el GPA de una persona (r = .518) incluso después de controlar la depresión. Discusión y conclusión Los hallazgos indican que una salud mental sólida, una situación financiera favorable y relaciones interpersonales positivas son cruciales para lograr un desempeño académico óptimo en los estudiantes de medicina. Estos resultados enfatizan la necesidad de abordar los problemas de salud mental, promover un entorno social de apoyo y brindar asistencia financiera para mejorar los resultados educativos de los estudiantes de medicina.
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Ecological theory posits that temporal stability patterns in plant populations are associated with differences in species' ecological strategies. However, empirical evidence is lacking about which traits, or trade-offs, underlie species stability, especially across different biomes. We compiled a worldwide collection of long-term permanent vegetation records (greater than 7000 plots from 78 datasets) from a large range of habitats which we combined with existing trait databases. We tested whether the observed inter-annual variability in species abundance (coefficient of variation) was related to multiple individual traits. We found that populations with greater leaf dry matter content and seed mass were more stable over time. Despite the variability explained by these traits being low, their effect was consistent across different datasets. Other traits played a significant, albeit weaker, role in species stability, and the inclusion of multi-variate axes or phylogeny did not substantially modify nor improve predictions. These results provide empirical evidence and highlight the relevance of specific ecological trade-offs, i.e. in different resource-use and dispersal strategies, for plant populations stability across multiple biomes. Further research is, however, necessary to integrate and evaluate the role of other specific traits, often not available in databases, and intraspecific trait variability in modulating species stability.
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Ecossistema , Plantas , Filogenia , Sementes , Fenótipo , Folhas de PlantaRESUMO
This study aimed to identify the most important variables of male and female beach handball workload demands and compare them by sex. A total of 92 elite Brazilian beach handball players (54 male: age 22.1 ± 2.6 years, height 1.8 ± 0.5 m, weight 77.6 ± 13.4 kg; and 38 female: age 24.4 ± 5.5 years, height 1.7 ± 0.5 m, weight 67.5 ± 6.5 kg) were analyzed in 24 official matches during a four-day congested tournament. From 250 variables measured by the inertial measurement unit, fourteen were extracted for analysis using Principal Component Analysis as selection criteria. Five Principal Components (PC) were extracted that explained 81.2-82.8% of total variance (overview of workload demands during beach handball). Specifically, 36.2-39.3% was explained by PC1 (DistanceExpl, Distance, Distance4-7 km/h, and Acc), 15-18% by PC2 (AccMax, Acc3-4 m/s, Dec4-3 m/s), 10.7-12.9% by PC3 (JumpsAvg Take-Off, JumpsAvg Landing and PLRT), 8-9.4% by PC4 (Distance> 18.1 km/h, SpeedMax), and 6.7-7.7% by PC5 (HRAvg and Step Balance). Sex-related differences were found in the PC distribution of variables, as well as in selected variables (HRAvg, Dec4-3 m/s, Acc3-4 m/s, JumpsAvg Take-Off, JumpsAvg Landing, AccMax, Distance, Distance4-7 km/h, Acc, SpeedMax) with higher values in male players (p < .05). In conclusion, the sex-related PC distribution and workload demands in beach handball should consider for training design and injury prevention programs.