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Velocidad - Atletismo
No full textEl documento es material de apoyo para el Curso de Entrenadores de Atletismo, aborda de manera exhaustiva el fenómeno de la velocidad en el ser humano y su aplicación en el ámbito deportivo, con especial énfasis en la disciplina del atletismo.
En primer lugar, los autores sitúan la carrera dentro del marco evolutivo humano, explicando cómo el bipedalismo y las adaptaciones anatómicas y fisiológicas permitieron al ser humano desarrollar tanto la resistencia como la capacidad de sprint. Factores como la termorregulación mediante el sudor, la eficiencia energética en rangos amplios de velocidad y la independencia entre ciclo respiratorio y locomotor son señalados como ventajas evolutivas determinantes. Estas características, aunque alejaron al ser humano de los animales más rápidos, le otorgaron una notable capacidad de resistencia que ha tenido gran impacto en la supervivencia y, posteriormente, en el deporte.
El texto también analiza los factores limitantes de la velocidad en humanos, tales como la proporción de fibras musculares, la estructura pélvica, la elasticidad de los tendones y la biomecánica del tronco. Estos condicionantes explican por qué el hombre no alcanza las velocidades máximas de animales como el guepardo o el caballo, aunque sí es capaz de sostener esfuerzos prolongados superiores a los de muchas especies.
Desde la perspectiva deportiva, se expone la importancia de la velocidad como capacidad determinante en múltiples disciplinas, no solo en pruebas atléticas puras, sino también en deportes colectivos y de combate. La velocidad se entiende como un constructo amplio que abarca la reacción, la ejecución técnica y la toma de decisiones bajo presión, y no simplemente como desplazamiento rápido. El manual destaca la necesidad de entrenar tanto las capacidades físicas como las cognitivas para optimizar el rendimiento.
En cuanto a las pruebas atléticas, se definen como carreras de velocidad aquellas que van desde los 60 hasta los 400 metros, incluyendo variantes con vallas. Se revisa su evolución histórica, desde el estadio griego hasta el atletismo moderno, y se detallan las características morfológicas y funcionales de los velocistas de élite, tales como la proporción muscular, la longitud de zancada, la frecuencia y la técnica de salida. Además, se discuten los avances tecnológicos —como las superficies de las pistas, el calzado o la biomecánica aplicada— que han permitido la mejora progresiva de los récords.The document is a support material for the Athletics Coaches Course. It provides an exhaustive examination of the phenomenon of speed in human beings and its application in the sporting field, with special emphasis on the discipline of athletics.
First, the authors place running within the human evolutionary framework, explaining how bipedalism and anatomical and physiological adaptations enabled humans to develop both endurance and sprinting capacity. Factors such as thermoregulation through sweating, energy efficiency across wide ranges of running speed, and the independence between respiratory and locomotor cycles are highlighted as decisive evolutionary advantages. These features, although they placed humans at a disadvantage compared to faster animals, granted them a remarkable endurance capacity that had a significant impact on survival and, later, on sport.
The text also analyzes the limiting factors of speed in humans, such as the proportion of muscle fibers, pelvic structure, tendon elasticity, and trunk biomechanics. These constraints explain why humans cannot reach the top speeds of animals such as the cheetah or the horse, although they are able to sustain prolonged efforts superior to those of many species.
From the sporting perspective, the document emphasizes the importance of speed as a determining capacity in multiple disciplines, not only in pure athletic events but also in team and combat sports. Speed is understood as a broad construct that encompasses reaction, technical execution, and decision-making under pressure, and not simply as rapid movement. The manual underlines the need to train both physical and cognitive capacities to optimize performance.
With regard to athletic events, sprint races are defined as those ranging from 60 to 400 meters, including hurdle races. The text reviews their historical evolution, from the Greek stadion to modern athletics, and describes the morphological and functional characteristics of elite sprinters, such as muscle distribution, stride length, stride frequency, and starting technique. Furthermore, it discusses technological advances—such as track surfaces, footwear, and applied biomechanics—that have enabled the progressive improvement of records.Actividad Física y DeporteDeport
Catéteres de acceso vascular con recubrimiento de hidrogeles biofuncionales. Estudio experimental in vitro
Full text linkMedicinaMedicin
Estudio clínico aleatorizado, doble ciego y controlado con placebo para evaluar el efecto de un preparado probiótico y administrado a pacientes con acné
Full text linkEn los últimos años, se ha puesto en evidencia el papel de la microbiota intestinal en algunas enfermedades inflamatorias de la piel, incluido el acné vulgar, lo cual sugiere que los probióticos podrían ser de utilidad en la modulación de la microbiota, mejorando el curso clínico de esta enfermedad.
Esta tesis se basa en un ensayo clínico aleatorizado, doble ciego, controlado con placebo, de 12 semanas de duración y con pacientes de 12 a 30 años que padecen acné vulgar. El producto en estudio ha sido una cápsula que contenía cepas probióticas de Lacticaseibacillus rhamnosus y Arthrospira platensis.
Los pacientes que presentaron mejoría en la Escala Global de Severidad del Acné fueron 10 de 34 (29.41%) en el grupo de placebo, en comparación con 20 de 40 (50%) en el grupo con tratamiento probiótico (p=0.03). También se observó una reducción significativa (p=0.03) en el número de lesiones de acné no inflamatorias en el grupo de probióticos (-18.60 [-24.38 a -12.82]) en comparación con el grupo de placebo (-10,54 [-17.43 a -3.66]). En cuanto al número total de lesiones, se observó una reducción que casi alcanzaba significancia estadística (p=0.06) en el grupo de probióticos (-27.94 [-36.35 a -19.53]) en comparación con el grupo de placebo (-18.31 [-28.21 a -8.41]). Además, los pacientes con mejoría según el Sistema Global de Clasificación del acné fueron 7 de 34 (20.58%) en el grupo de placebo frente a 17 de 40 (42.50%) en el grupo de probióticos (p=0.02). El número de eventos adversos fue similar en ambos grupos y todos ellos fueron catalogados como leves. En conclusión, el probiótico utilizado en este estudio fue efectivo y bien tolerado, y debería considerarse como tratamiento coadyuvante para pacientes con acné vulgar.FarmaciaMedicin
Impact of Virtual Reality Alone and in Combination with Conventional Therapy on Balance in Parkinson's Disease: A Systematic Review with a Meta-Analysis of Randomized Controlled Trials
Full text linkBackground and Objectives: Virtual reality (VR)-based interventions provide immersive and interactive environments that can enhance motor learning and deliver real-time feedback, offering potential advantages over conventional therapies. This systematic review evaluated the impact of non-immersive and immersive VR exergaming interventions versus conventional therapy on balance in Parkinson's disease (PD) through a detailed analysis of randomized controlled trials (RCTs). Materials and Methods: A comprehensive search was conducted across the PubMed, Lilacs, IBECS, CENTRAL, Web of Science (WOS), EBSCOHost, and SciELO databases. Article selection and duplicate removal were managed using Rayyan QCRI. The quality of the evidence was assessed using the GRADE system. Results: From an initial screening of 100 studies, 58 underwent title and abstract screening. After full-text evaluation, 11 RCTs met the inclusion criteria, involving 518 participants with PD (average age: 67.3 years; 67.95% men). The balance outcomes were primarily measured using the Berg balance scale (BBS), employed in most studies (n = 9). The pooled analysis demonstrated a significant improvement in the balance scores for the experimental groups compared to the controls, with a standardized mean difference (SMD) of 0.58 [95% CI: 0.07, 1.09, p = 0.03]. However, the heterogeneity was substantial (I2 = 77%). The analysis of the six-minute walking test (6 MWT), as another outcome of four articles, revealed a mean difference of 32.99 m [95% CI: -8.02, 74.00], but the effect was not statistically significant (p = 0.11). The heterogeneity for this outcome was moderate (I2 = 41%), indicating some variability across studies. Alternative tools, such as the Tinetti Performance-Oriented Mobility Assessment (POMA) scale, the UPDRS III, and the sensory organization test (SOT), were also evaluated where possible. Conclusions: VR-based interventions offer promise for improving balance in Parkinson's disease, enhancing rehabilitation engagement. Their integration into clinical practice could complement conventional therapy. However, further research is needed to optimize protocols, standardize parameters, and maximize their impact on mobility, independence, and quality of life.Terapia y RehabilitaciónFisioterapia, Podología y Terapia Ocupaciona
Matched pairs demonstrate robustness against inter-assay variability
Full text linkMachine learning models for chemistry require large datasets, often compiled by combining data from multiple assays. However, combining data without careful curation can introduce significant noise. While absolute values from different assays are rarely comparable, trends or differences between compounds are often assumed to be consistent. This study evaluates that assumption by analyzing potency differences between matched compound pairs across assays and assessing the impact of assay metadata curation on error reduction. We find that potency differences between matched pairs exhibit less variability than individual compound measurements, suggesting systematic assay differences may partially cancel out in paired data. Metadata curation further improves inter-assay agreement, albeit at the cost of dataset size. For minimally curated compound pairs, agreement within 0.3 pChEMBL units was found to be 44–46% for Ki and IC50 values respectively, which improved to 66–79% after curation. Similarly, the percentage of pairs with differences exceeding 1 pChEMBL unit dropped from 12 to 15% to 6–8% with extensive curation. These results establish a benchmark for expected noise in matched molecular pair data from the ChEMBL database, offering practical metrics for data quality assessment.FarmaciaCiencias de la Salu
Emotional Regulation and Risk of Eating Disorders in Adolescent Athletes
Full text linkEating Disorders (EDs) are more prevalent among athletes due to performance pressure and body ideals. Emotional regulation is a key factor in ED. This study aimed to (1) examine the reliability and structural validity of the Emotion Regulation Questionnaire for Children and Adolescents (ERQ-CA) in adolescent Mexican athletes, and (2) analyze associations between emotional regulation strategies (expressive suppression and cognitive reappraisal) and ED risk factors (drive for thinness, body dissatisfaction, and bulimia). An instru mental, cross-sectional design was employed with 295 Mexican athletes (Mage = 16.85, SD = 3.27). The ERQ-CA demonstrated good psychometric properties, with acceptable reliability (ω > 0.70) and excellent fit for the two-factor model (CFI = 0.995, RMSEA = 0.018). Emotional suppression was positively associated with all ED risk indicators, whereas cognitive reappraisal was negatively associated. These findings highlight that individual differences in emotion regulation are linked to ED risk in adolescent athletes. Monitoring expressive suppression and promoting cognitive reappraisal may serve as supportive strate gies for coaches, parents, and mental health professionals, enhancing emotional flexibility and potentially reducing ED risk.PsicologíaEducació
Marca personal a través de la creatividad: Análisis de la Influencer 'Marcela Peraz’
No full textConsolidar una marca personal en las redes sociales no es una tarea sencilla. Requiere un proceso de aprendizaje continuo basado en prueba y error. Sin embargo, una vez alcanzada una buena reputación y lograda la conexión con la audiencia, se abre la posibilidad de generar beneficios tanto económicos como personales. Este trabajo presenta un caso de éxito de marca personal a través de la creatividad: ‘Marcela Peraz’, creadora de contenido en redes sociales, posicionada como una de las mejores artistas de maquillaje y body paint en Latinoamérica, con presencia destacada en TikTok, Facebook, Instagram y YouTube.Consolidating a personal brand on social media is not an easy task. It requires a continuous learning process based on trial and error. However, once a good reputation is achieved and a connection with the audience is established, the possibility of generating both economic and personal benefits opens up. This work presents a success story of personal branding through creativity: 'Marcela Peraz', a content creator on social media, positioned as one of the best make-up and body paint artists in Latin America, with a prominent presence on TikTok, Facebook, Instagram, and YouTube.Administración y Dirección de EmpresasEconomía y Empres
Immediate effects of three different upper trapezius trigger point techniques on pain intensity and pressure threshold in students with cervical pain: a randomized clinical trial
Full text linkObjective: To compare the effectiveness of three manual therapy protocols (Jones, Lewit, and Chaitow) with a
sham group in terms of pain pressure threshold and intensity.
Participants: Fifty-two physiotherapy bachelor students with neck pain lasting more than 3 days were recruited.
Outcomes: Pain was assessed with Numerical Rating Scale and Pressure Algometer, while cervical range of
motion was evaluated with the Baiobit Inertial sensor.
Intervention: An investigator, independent of the assessment and randomization, conducted all the interventions
and sham procedures. Specifically, the Jones group received pincer palpation with a 1-min duration of ischemic
compression, followed by 90 s of the no-pain Strain-Counterstrain technique. The Lewit group underwent flat
palpation for 1 min, accompanied by 40 s of intermittent compression and post-isometric relaxation. The
Chaitow group received deep palpation for 1 min, followed by the pressure release position lasting 20 s to 1 min,
concluding with the muscle energy technique. The Sham group received only flat palpation and a 3-min
homolateral muscle shortening position.
Results: Effects for all three techniques (Chaitow/Lewit/Jones) when comparing them to sham were not significant on pain intensity . No adverse events or undesirable effects were observed during the study.
Conclusion: Immediate effects on pain intensity and pressure threshold are not directly attributable to any of the
three tested trigger techniques.Terapia y RehabilitaciónFisioterapia, Podología y Terapia Ocupaciona
Geospatial Feature-Based Path Loss Prediction at 1800 MHz in Covenant University Campus with Tree Ensembles, Kernel-Based Methods, and a Shallow Neural Network
Full text linkThis paper investigates within-scene path loss prediction at 1.8 GHz in a smart-campus micro-urban environment using multivariate machine-learning (ML) models. We leverage an open measurement campaign from Covenant University (Nigeria) comprising three routes with per-sample geospatial predictors—longitude, latitude, altitude, elevation, Tx–Rx distance, and clutter height—and train Random Forests (RF), Gradient Boosting (GB), Support Vector Regression (SVR), Gaussian Processes (GP), and a shallow neural network (NN). A unified pipeline with 5-fold cross-validation (CV), seeded reproducibility, and Optuna-driven hyperparameter search is adopted; performance is reported as RMSE/MAE/R2 (mean ± sd). To contextualize feature reliability, we include Pearson correlation heatmaps and Variance Inflation Factors (VIFs), a systematic ablation of predictors, and TreeSHAP beeswarm analyses on held-out splits. We also evaluate spatially aware validation (blocked CV within route and leave-one-route-out checks) to mitigate optimism due to spatial autocorrelation. Results show that multivariate ML consistently outperforms classical empirical formulas (COST-231, ECC-33) in this campus setting, with RF achieving the lowest errors across routes (RMSE ≈ 2.14/2.16/2.95 dB for X/Y/Z, respectively), while GB ranks second and kernel methods (SVR/GP) and the NN trail closely behind. Ablation confirms that distance plus coordinates drive the largest gains, with terrain/clutter providing route-dependent refinements. SHAP analyses align with these findings, highlighting stable, interpretable contributions of geospatial covariates. Spatial CV increases absolute errors moderately but preserves model ranking, supporting the robustness of conclusions. Overall, scenario-aware, multivariate ML yields material accuracy gains for smart-campus planning at 1.8 GHz.Ingeniería, Industria y ConstrucciónEscuela Politécnic