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1.
PeerJ ; 12: e17293, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770099

RESUMO

Background: Aniseikonia is a binocular vision disorder that has been associated with asthenopic symptoms. However, asthenopia has been evaluated with subjective tests that make difficult to determine the level of aniseikonia. This study aims to objectively evaluate the impact of induced aniseikonia at different levels on visual fatigue by measuring the orbicularis oculi muscle activity in the dominant and non-dominant eyes while performing a reading task. Methods: Twenty-four collegiate students (24.00 ± 3.86 years) participated in this study. Participants read a passage for 7 minutes under four degrees of aniseikonia (0%, 3%, 5% and 10%) at 50 cm. Orbicularis oculi muscle activity of the dominant and non-dominant eye was recorded by surface electromyography. In addition, visual discomfort was assessed after each task by completing a questionnaire. Results: Orbicularis oculi muscle activity increased under induced aniseikonia (i.e., greater values for the 10% condition in comparison to 0%, and 3% conditions (p = 0.034 and p = 0.023, respectively)). No statistically significant differences were observed in orbicularis oculi muscle activity for the time on task and between the dominant and non-dominant eyes. Additionally, higher levels of subjective visual discomfort were observed for lower degrees of induced aniseikonia. Conclusion: Induced aniseikonia increases visual fatigue at high aniseikonia degrees as measured by the orbicularis oculi muscle activity, and at low degrees as measured with subjective questionnaires. These findings may be of relevance to better understand the visual symptomatology of aniseikonia.


Assuntos
Aniseiconia , Eletromiografia , Leitura , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Aniseiconia/fisiopatologia , Músculos Oculomotores/fisiologia , Astenopia/fisiopatologia , Astenopia/etiologia , Computadores , Músculos Faciais/fisiologia
2.
J Sci Med Sport ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38644066

RESUMO

OBJECTIVES: This study aimed to analyze how spatiotemporal gait parameters, active knee extension range of motion, muscle activity, and self-perceived function change over a seven-day period in healthy individuals after exercise-induced muscle damage (EIMD) in the hamstrings. DESIGN: Longitudinal cohort study. METHODS: Twenty-four healthy males participated in four sessions before and after EIMD (pre-EIMD, 48 h, 96 h, and 168 h post-EIMD). A single-leg deadlift exercise was performed to provoke EIMD in the hamstrings of the dominant leg. Lower limb function perception, spatiotemporal gait parameters, active knee extension range of motion, and electromyographic (EMG) activity of the semitendinosus and biceps femoris muscles during gait and maximal isometric contraction were assessed bilaterally. RESULTS: At 48 h, the EIMD-side showed reduced step length, active knee extension range of motion, maximal strength and EMG activity compared to baseline (P < 0.042), while increased relative EMG activity in the biceps femoris during gait (P = 0.001). At 96 h, step length and EMG activity on the EIMD-side reached similar values to those at baseline, whereas lower limb function perception and active knee extension range of motion returned to baseline state at 168 h post-EIMD. No changes over time were observed on the control-side. CONCLUSIONS: Recovery from EIMD requires a multimodal assessment since the different parameters affected by EIMD recover at different paces. Active range of motion appears to be the last variable to fully recover. Self-perceived function should not be considered in isolation as it does not represent complete functional recovery.

3.
JMIR Form Res ; 8: e52344, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640473

RESUMO

BACKGROUND: Functional impairment is one of the most decisive prognostic factors in patients with complex chronic diseases. A more significant functional impairment indicates that the disease is progressing, which requires implementing diagnostic and therapeutic actions that stop the exacerbation of the disease. OBJECTIVE: This study aimed to predict alterations in the clinical condition of patients with complex chronic diseases by predicting the Barthel Index (BI), to assess their clinical and functional status using an artificial intelligence model and data collected through an internet of things mobility device. METHODS: A 2-phase pilot prospective single-center observational study was designed. During both phases, patients were recruited, and a wearable activity tracker was allocated to gather physical activity data. Patients were categorized into class A (BI≤20; total dependence), class B (2060; moderate or mild dependence, or independent). Data preprocessing and machine learning techniques were used to analyze mobility data. A decision tree was used to achieve a robust and interpretable model. To assess the quality of the predictions, several metrics including the mean absolute error, median absolute error, and root mean squared error were considered. Statistical analysis was performed using SPSS and Python for the machine learning modeling. RESULTS: Overall, 90 patients with complex chronic diseases were included: 50 during phase 1 (class A: n=10; class B: n=20; and class C: n=20) and 40 during phase 2 (class B: n=20 and class C: n=20). Most patients (n=85, 94%) had a caregiver. The mean value of the BI was 58.31 (SD 24.5). Concerning mobility aids, 60% (n=52) of patients required no aids, whereas the others required walkers (n=18, 20%), wheelchairs (n=15, 17%), canes (n=4, 7%), and crutches (n=1, 1%). Regarding clinical complexity, 85% (n=76) met patient with polypathology criteria with a mean of 2.7 (SD 1.25) categories, 69% (n=61) met the frailty criteria, and 21% (n=19) met the patients with complex chronic diseases criteria. The most characteristic symptoms were dyspnea (n=73, 82%), chronic pain (n=63, 70%), asthenia (n=62, 68%), and anxiety (n=41, 46%). Polypharmacy was presented in 87% (n=78) of patients. The most important variables for predicting the BI were identified as the maximum step count during evening and morning periods and the absence of a mobility device. The model exhibited consistency in the median prediction error with a median absolute error close to 5 in the training, validation, and production-like test sets. The model accuracy for identifying the BI class was 91%, 88%, and 90% in the training, validation, and test sets, respectively. CONCLUSIONS: Using commercially available mobility recording devices makes it possible to identify different mobility patterns and relate them to functional capacity in patients with polypathology according to the BI without using clinical parameters.

4.
J Sports Sci ; 42(5): 404-414, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38602304

RESUMO

The purpose was to compare two non-laboratory based running retraining programs on lower limb and trunk kinematics in recreational runners. Seventy recreational runners (30 ± 7.3 years old, 40% female) were randomised to a barefoot running group (BAR), a group wearing a digital metronome with their basal cadence increased by 10% (CAD), and a control group (CON). BAR and CAD groups included intervals from 15 to 40 min over 10 weeks and 3 days/week. 3D sagittal kinematics of the ankle, knee, hip, pelvis, and trunk were measured before and after the retraining program, at comfortable and high speeds. A 3 × 2 mixed ANOVA revealed that BAR and CAD groups increased knee and hip flexion at footstrike, increased peak hip flexion during stance and flight phase, decreased peak hip extension during flight phase, and increased anterior pelvic tilt at both speeds after retraining. In addition, BAR increased ankle plantar flexion at footstrike and increased anterior trunk tilt. Both retraining programs demonstrated significant moderate to large effect size changes in parameters that could reduce the mechanical risks of injury associated with excessive knee stress, which is of interest to coaches, runners and those prescribing rehabilitation and injury prevention programs.


Assuntos
Extremidade Inferior , Pelve , Corrida , Tronco , Humanos , Corrida/fisiologia , Fenômenos Biomecânicos , Feminino , Masculino , Tronco/fisiologia , Adulto , Extremidade Inferior/fisiologia , Pelve/fisiologia , Pé/fisiologia , Adulto Jovem , Joelho/fisiologia , Tornozelo/fisiologia , Quadril/fisiologia , Marcha/fisiologia
5.
Cir Cir ; 92(1): 104-111, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537245

RESUMO

OBJECTIVE: To organize the experience and international knowledge in the surgical management and staging of colorectal endometriosis, with a management proposal in stages. METHOD: An extensive non-systematic review of the literature was carried to organize the disease in stages (limited, intermediate and advanced) according to a scoring system, which considers the characteristics of the endometrioma, the personal history and surgical findings. We tested the proposed staging in a retrospective group of patients. RESULTS: From January 2017 to April 2023, we collected 19 patients with a confirmed diagnosis of colorectal endometriosis, treated laparoscopically, by the same group of surgeons, in whom we found a strong correlation between the stage of the disease and the presence of complications that required reinterventions. CONCLUSIONS: We suggest a sequence of colorectal surgical management in stages according to the staging of the disease and we hope that this work will be followed by joint efforts to test it prospectively in order to compare results between hospital centers and make planned decisions.


OBJETIVO: Organizar la experiencia y el conocimiento internacional en el manejo quirúrgico y la estadificación de la endometriosis colorrectal, con una propuesta de manejo por etapas. MÉTODO: Se realizó una revisión amplia no sistemática de la literatura para organizar la enfermedad en etapas (limitada, intermedia y avanzada) de acuerdo con un sistema de puntuación que considera las características del endometrioma, los antecedentes personales y los hallazgos en la cirugía. La estatificación propuesta se probó en un grupo retrospectivo de pacientes. RESULTADOS: De enero de 2017 a abril de 2023 recopilamos 19 pacientes con diagnóstico confirmado de endometriosis colorrectal, tratadas por vía laparoscópica, por el mismo grupo de cirujanos, en las que encontramos una fuerte correlación entre el estadio de la enfermedad y la presencia de complicaciones que requirieron reintervenciones. CONCLUSIONES: Sugerimos una secuencia de manejo quirúrgico colorrectal en etapas de acuerdo con la estadificación de la enfermedad y esperamos que el presente trabajo sea seguido de esfuerzos compartidos por probarla de manera prospectiva para poder comparar resultados entre centros hospitalarios y tomar decisiones planificadas.


Assuntos
Neoplasias Colorretais , Endometriose , Laparoscopia , Feminino , Humanos , Endometriose/cirurgia , Endometriose/complicações , Estudos Retrospectivos , Neoplasias Colorretais/cirurgia , Laparoscopia/métodos
6.
Sensors (Basel) ; 23(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37430490

RESUMO

Markerless motion capture systems (MCS) have been developed as an alternative solution to overcome the limitations of 3D MCS as they provide a more practical and efficient setup process given, among other factors, the lack of sensors attached to the body. However, this might affect the accuracy of the measures recorded. Thus, this study is aimed at evaluating the level of agreement between a markerless MSC (i.e., MotionMetrix) and an optoelectronic MCS (i.e., Qualisys). For such purpose, 24 healthy young adults were assessed for walking (at 5 km/h) and running (at 10 and 15 km/h) in a single session. The parameters obtained from MotionMetrix and Qualisys were tested in terms of level of agreement. When walking at 5 km/h, the MotionMetrix system significantly underestimated the stance and swing phases, as well as the load and pre-swing phases (p < 0.05) reporting also relatively low systematic bias (i.e., ≤ -0.03 s) and standard error of the estimate (SEE) (i.e., ≤0.02 s). The level of agreement between measurements was perfect (r > 0.9) for step length left and cadence and very large (r > 0.7) for step time left, gait cycle, and stride length. Regarding running at 10 km/h, bias and SEE analysis revealed significant differences for most of the variables except for stride time, rate and length, swing knee flexion for both legs, and thigh flexion left. The level of agreement between measurements was very large (r > 0.7) for stride time and rate, stride length, and vertical displacement. At 15 km/h, bias and SEE revealed significant differences for vertical displacement, landing knee flexion for both legs, stance knee flexion left, thigh flexion, and extension for both legs. The level of agreement between measurements in running at 15 km/h was almost perfect (r > 0.9) when comparing Qualisys and MotionMetrix parameters for stride time and rate, and stride length. The agreement between the two motion capture systems varied for different variables and speeds of locomotion, with some variables demonstrating high agreement while others showed poor agreement. Nonetheless, the findings presented here suggest that the MotionMetrix system is a promising option for sports practitioners and clinicians interested in measuring gait variables, particularly in the contexts examined in the study.


Assuntos
Captura de Movimento , Corrida , Adulto Jovem , Humanos , Caminhada , Marcha , Locomoção
7.
J Org Chem ; 88(14): 10156-10163, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37428953

RESUMO

5'-O-(2-Methoxyisopropyl) (MIP)-protected 2'-deoxynucleosides as chiral P(V)-building blocks, based on the limonene-derived oxathiaphospholane sulfide, were synthesized and used for the assembly of di-, tri-, and tetranucleotide phosphorothioates on a tetrapodal pentaerythritol-derived soluble support. The synthesis cycle consisted of two reactions and two precipitations: (1) the coupling under basic conditions, followed by neutralization and precipitation and (2) an acid catalyzed 5'-O-deacetalization, followed by neutralization and precipitation. The simple P(V) chemistry together with the facile 5'-O-MIP deprotection proved efficient in the liquid phase oligonucleotide synthesis (LPOS). Ammonolysis released nearly homogeneous Rp or Sp phosphorothioate diastereomers in ca. 80% yield/synthesis cycle.


Assuntos
Oligonucleotídeos Fosforotioatos , Oligonucleotídeos Fosforotioatos/química , Estereoisomerismo
8.
Healthcare (Basel) ; 11(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37297740

RESUMO

Parkinson's disease (PD) is a neurological condition that is chronic and worsens over time, which presents a challenging diagnosis. An accurate diagnosis is required to recognize PD patients from healthy individuals. Diagnosing PD at early stages can reduce the severity of this disorder and improve the patient's living conditions. Algorithms based on associative memory (AM) have been applied in PD diagnosis using voice samples of patients with this health condition. Even though AM models have achieved competitive results in PD classification, they do not have any embedded component in the AM model that can identify and remove irrelevant features, which would consequently improve the classification performance. In this paper, we present an improvement to the smallest normalized difference associative memory (SNDAM) algorithm by means of a learning reinforcement phase that improves classification performance of SNDAM when it is applied to PD diagnosis. For the experimental phase, two datasets that have been widely applied for PD diagnosis were used. Both datasets were gathered from voice samples from healthy people and from patients who suffer from this condition at an early stage of PD. These datasets are publicly accessible in the UCI Machine Learning Repository. The efficiency of the ISNDAM model was contrasted with that of seventy other models implemented in the WEKA workbench and was compared to the performance of previous studies. A statistical significance analysis was performed to verify that the performance differences between the compared models were statistically significant. The experimental findings allow us to affirm that the proposed improvement in the SNDAM algorithm, called ISNDAM, effectively increases the classification performance compared against well-known algorithms. ISNDAM achieves a classification accuracy of 99.48%, followed by ANN Levenberg-Marquardt with 95.89% and SVM RBF kernel with 88.21%, using Dataset 1. ISNDAM achieves a classification accuracy of 99.66%, followed by SVM IMF1 with 96.54% and RF IMF1 with 94.89%, using Dataset 2. The experimental findings show that ISNDAM achieves competitive performance on both datasets and that statistical significance tests confirm that ISNDAM delivers classification performance equivalent to that of models published in previous studies.

9.
Int J Sports Med ; 44(8): 535-544, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37130547

RESUMO

Over the years, soccer has become more physically demanding; the number and frequency of high-intensity actions have increased, and these activities are decisive in determining the match outcome. Importantly, the reductionist approach commonly used to analyze high-intensity actions does not contemplate a more contextualized perspective on soccer performance. Traditionally, most investigations have only provided quantitative data regarding sprints (i. e. time, distances, frequency) without examining "how" (e. g. type of trajectory or starting position) and "why" (e. g. tactical role) soccer players sprint. In fact, other high-intensity actions, apart from running, are not even mentioned (i. e. curve sprints, change of direction, and specific-jump tasks). This has led to the use of tests and interventions that do not accurately reflect real game actions. Given the true technical-tactical-physical demands of each playing position, this narrative review collected a wide-spectrum of current soccer-related articles and provided a discussion regarding high-intensity actions, with a positional-based approach. In this narrative review, practitioners are encouraged to contemplate and consider the different elements that characterize high-intensity actions in soccer, in order to assess and train soccer players under a more sport-specific and integrative perspective.


Assuntos
Desempenho Atlético , Corrida , Futebol , Humanos
10.
Sensors (Basel) ; 23(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36904808

RESUMO

Optoelectronic motion capture systems are considered the gold standard for measuring walking and running kinematics parameters. However, these systems prerequisites are not feasible for practitioners as they entail a laboratory environment and time to process and calculate the data. Therefore, this study aims to evaluate the validity of the three-sensor RunScribe Sacral Gait Lab™ inertial measurement unit (IMU) in measuring pelvic kinematics in terms of vertical oscillation, tilt, obliquity, rotational range of motion, and the maximum angular rates during walking and running on a treadmill. Pelvic kinematic parameters were measured simultaneously using an eight-camera motion analysis system (Qualisys Medical AB, GÖTEBORG, Sweden) and the three-sensor RunScribe Sacral Gait Lab™ (Scribe Lab. Inc. San Francisco, CA, USA) in a sample of 16 healthy young adults. An acceptable level of agreement was considered if the following criteria were met: low bias and SEE (<0.2 times the between-subject differences SD), almost perfect (r > 0.90), and good reliability (ICC > 0.81). The results obtained reveal that the three-sensor RunScribe Sacral Gait Lab™ IMU did not reach the validity criteria established for any of the variables and velocities tested. The results obtained therefore show significant differences between the systems for the pelvic kinematic parameters measured during both walking and running.


Assuntos
Marcha , Pelve , Adulto Jovem , Humanos , Fenômenos Biomecânicos , Reprodutibilidade dos Testes , Locomoção , Caminhada
11.
Appl Opt ; 62(1): 108-116, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36606852

RESUMO

The development and deployment of a real-time, in situ, non-invasive sensor to monitor the concentration of H 2 O during in situ combustion (ISC) experiments with a heavy-crude oil is described. A real-time sensor to monitor the gas-phase products from ISC can support the study of the kinetics of the complex chemical reactive system in ISC. The mole fraction of H 2 O was measured using tunable diode laser (TDL) absorption spectroscopy coupled with 1f-normalized wavelength modulation spectroscopy (WMS) and 2f detection. The WMS 2f/1f strategy was used to enhance sensitivity with effective noise rejection, particularly suitable when characterizing the water vapor evolved from oil-water emulsions. H 2 O was measured at 3934.10c m -1 from the fundamental band v 3. That transition was selected using the HITRAN database to increase the line strength and minimize interference from neighbor compounds. Measurements of H 2 O concentration were conducted at ambient temperature and pressure using a reference cell (H 2 O=2% at 98.6 kPa) to validate the sensor architecture under controlled laboratory environments. The TDL sensor was also successfully validated during real ISC experiments involving heavy-crude oil. Validation and combustion experiments showed the potential of the TDL-based sensor for non-invasive, real-time, in situ measurements of gas-phase species in conditions similar to those of laboratory-scale experimental ISC tests.

12.
PeerJ ; 11: e14411, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36684666

RESUMO

Background: Antimicrobial resistance is a global concern. Analysis of sterile fluids is essential because microorganisms are defined as significant in most cases. Blood, cerebrospinal, and pleural fluids are frequently received in the microbiology lab because they are associated with considerable rates of morbi-mortality. Knowledge of epidemiology in these samples is needed to choose proper empirical treatments due to the importance of reducing selection pressure. Methods: We used retrospective laboratory data of blood, CSF, and pleural fluid collected from patients in Mexico between 2019 and 2020. Each laboratory identified the strains and tested susceptibility using its routine methods. For Streptococcus pneumoniae, a comparative analysis was performed with data from the broth microdilution method. Results: Forty-five centers participated in the study, with 30,746 clinical isolates from blood, 2,429 from pleural fluid, and 2,275 from CSF. For blood and CSF, Staphylococcus epidermidis was the most frequent. For blood, among gram negatives, the most frequent was Escherichia coli. Among Enterobacterales, 9.8% of K. pneumoniae were carbapenem-resistant. For S. pneumoniae, similar resistance percentages were observed for levofloxacin, cefotaxime, and vancomycin. For CSF, the most frequent gram-negative was E. coli. In Acinetobacter baumannii, carbapenem resistance was 71.4%. The most frequent species detected for pleural fluid was E. coli; in A. baumannii, carbapenem resistance was 96.3%. Conclusion: Gram-negative bacteria, with E. coli most prevalent, are frequently recovered from CSF, blood, and pleural fluid. In S. pneumoniae, the routine, conventional methods showed good agreement in detecting resistance percentages for erythromycin, levofloxacin, and vancomycin.


Assuntos
Antibacterianos , Vancomicina , Humanos , Antibacterianos/farmacologia , Vancomicina/farmacologia , Levofloxacino , Escherichia coli , Incidência , Estudos Retrospectivos , Bactérias , Carbapenêmicos , Resistência a Medicamentos
13.
Sports Biomech ; 22(3): 388-409, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35748066

RESUMO

This systematic review aims to synthesise the effects of current shoe models in each shoe category and their specific features on running economy, performance and biomechanics. Electronic databases such as Web of Science, SPORTDiscuss, PubMed and Scopus were used to identify studies from 2015 to date. Due to the existing lack of consensus to define running shoes, only studies that specified the shoe brand and models used to assess their effect over runners with a certain level of fitness and training routine were included. Quality assessment of cross-sectional and intervention studies was conducted by three independent raters using a modified version of the Quality Index and the PEDro scale, respectively. A total of 36 articles were finally included, involving the analysis of 61 different shoe models over 10 different topics (i.e., running economy, running performance, spatiotemporal parameters, ground reaction forces, joint stiffness, achilles tendon, plantar pressure, tibiofemoral load, foot strike pattern and joint coordination). With this review, runners and practitioners in the field that are concerned about selecting a suitable shoe for performance, training, or injury prevention functionality have clear information about the effects of the current shoe models and their specific features.


Assuntos
Corrida , Sapatos , Humanos , Fenômenos Biomecânicos , Estudos Transversais ,
14.
Clin Exp Optom ; 106(1): 85-90, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35057697

RESUMO

CLINICAL RELEVANCE: There is some controversy about the utility of prescribing blue-blocking filters to mitigate digital eye strain. We found that using commercially available blue-blocking filters was ineffective in reducing orbicularis oculi muscle activity and visual symptomatology during a 30-min reading task from a computer screen. BACKGROUND: There are some claims that blue-blocking (B-B) filters may be effective in reducing symptoms and signs of digital eye strain. However, recent studies have suggested that there is no sufficient evidence to support their use. This study assessed the short-term effects of a commercially available, B-B filter on orbicularis oculi (OO) muscle activity and symptoms of digital eye strain during the execution of a 30-min reading tas. METHODS: Twenty-three healthy young adults (22.9 ± 3.2 years of age) performed two reading tasks from a computer screen with or without a B-B filter on two different days. OO muscle activity was recorded by surface electromyography 4-5, 9-10, 14-15, 19-20, 24-25 and 29-30 min into the trial. Participants reported their perceived levels of visual discomfort and activation before and after completing the reading task. RESULTS: A Bayesian analysis favoured the null hypothesis that there was no change in OO muscle activity with or without using the B-B filter (Bayes Factor01 [BF01] = 7.08). Regarding symptomatology, the analysis favoured the time model that reading increased visual fatigue and discomfort but reduced activation levels (BF01 < 0.33 in all cases). However, our data did not support the alternative model that using B-B filter affected these visual symptoms. CONCLUSIONS: The B-B filter did not alter OO muscle activity or visual symptomatology significantly during the execution of a 30-min reading task in asymptomatic subjects. These findings support the idea that B-B filters do not attenuate signs and symptoms of digital eye strain.


Assuntos
Astenopia , Humanos , Adulto Jovem , Astenopia/diagnóstico , Teorema de Bayes , Computadores , Pálpebras , Transtornos da Visão
15.
Rev. esp. podol ; 34(2): 121-131, 2023. ilus
Artigo em Espanhol | IBECS | ID: ibc-229381

RESUMO

Este artículo examina la relación entre los patrones de pisada de corredores de larga distancia (Rearfoot Strike [RFS] y Non Rearfoot Strike [NRFS]) y varios aspectos como lesiones, rendimiento y biomecánica. A pesar de que correr se ha establecido como una actividad popular con beneficios cardiovasculares, respiratorios y psicológicos, conlleva un riesgo significativo de lesiones. Se encontró que la mayoría de los corredores adoptan un patrón RFS, que tiende a aumentar con la distancia recorrida, la fatiga y el uso de calzado amortiguado. Aunque algunos estudios sugieren una relación entre ciertos patrones de pisada y lesiones específicas, no hay suficiente evidencia para recomendar cambios en el patrón de pisada para la prevención de lesiones. Los corredores de élite tienden a usar un patrón NRFS más que los amateurs, pero la relación entre el patrón de pisada, el rendimiento y las variables biomecánicas es compleja y varía según el individuo. Se concluye que los profesionales de la salud y entrenadores deben considerar estas variaciones al asesorar a los corredores sobre técnicas y estrategias de entrenamiento, prevención, tratamiento y readaptación de lesiones (AU)


This paper examines the relationship between long-distance runners’ foot strike patterns (Rearfoot Strike [RFS] and Non Rearfoot Strike [NRFS]) and various aspects such as injuries, performance, and biomechanics. While running has established itself as a popular activity with cardiovascular, respiratory, and psychological benefits, it carries a significant risk of injuries. It was found that most runners adopt an RFS pattern, which tends to increase with distance covered and the use of cushioned footwear. Although some studies suggest a relationship between certain foot strike patterns and specific injuries, there is insufficient evidence to recommend changes in foot strike patterns for injury prevention. Elite runners tend to use an NRFS pattern more than amateurs, but the relationship between foot strike patterns, performance, and biomechanical variables is complex and varies indivually. It concludes that health professionals and coaches should consider these variations when advising runners on training techniques and strategies, prevention, treatment, and rehabilitation of injuries (AU)


Assuntos
Humanos , Traumatismos em Atletas/etiologia , Fenômenos Biomecânicos , Corrida/lesões
16.
Sci Rep ; 12(1): 17831, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284121

RESUMO

The magnonic band structure of two-dimensional chiral magnonic crystals is theoretically investigated. The proposed metamaterial involves a three-dimensional architecture, where a thin ferromagnetic layer is in contact with a two-dimensional periodic array of heavy-metal square islands. When these two materials are in contact, an anti-symmetric exchange coupling known as the Dzyaloshinskii-Moriya interaction (DMI) arises, which generates nonreciprocal spin waves and chiral magnetic order. The Landau-Lifshitz equation and the plane-wave method are employed to study the dynamic magnetic behavior. A systematic variation of geometric parameters, the DMI constant, and the filling fraction allows the examination of spin-wave propagation features, such as the spatial profiles of the dynamic magnetization, the isofrequency contours, and group velocities. In this study, it is found that omnidirectional flat magnonic bands are induced by a sufficiently strong Dzyaloshinskii-Moriya interaction underneath the heavy-metal islands, where the spin excitations are active. The theoretical results were substantiated by micromagnetic simulations. These findings are relevant for envisioning applications associated with spin-wave-based logic devices, where the nonreciprocity and channeling of the spin waves are of fundamental and practical scientific interest.

17.
J Org Chem ; 87(19): 13363-13366, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36161801

RESUMO

Azido nucleosides couple with phosphoramidites via an initial iminophosphorane, which eliminates acrylonitrile to generate the coupled dimer P(V) product. The vulnerable phosphite triester intermediate is bypassed entirely, making the methodology very suitable to solution-phase synthesis. This new coupling protocol requires no protection of the 5'-OH function and provides a new method of installing internucleosidic phosphorodiamidate bonds with near quantitative yields.


Assuntos
Acrilonitrila , Fosfitos , Nucleosídeos/química , Oligonucleotídeos/química , Polímeros
18.
Nanomaterials (Basel) ; 12(16)2022 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-36014650

RESUMO

Magnetization-graded ferromagnetic nanostrips are proposed as potential prospects to channel spin waves. Here, a controlled reduction of the saturation magnetization enables the localization of the propagating magnetic excitations in the same way that light is controlled in an optical fiber with a varying refraction index. The theoretical approach is based on the dynamic matrix method, where the magnetic nanostrip is divided into small sub-strips. The dipolar and exchange interactions between sub-strips have been considered to reproduce the spin-wave dynamics of the magnonic fiber. The transition from one strip to an infinite thin film is presented for the Damon-Eshbach geometry, where the nature of the spin-wave modes is discussed. An in-depth analysis of the spin-wave transport as a function of the saturation magnetization profile is provided. It is predicted that it is feasible to induce a remarkable channeling of the spin waves along the zones with a reduced saturation magnetization, even when such a reduction is tiny. The results are compared with micromagnetic simulations, where a good agreement is observed between both methods. The findings have relevance for envisioned future spin-wave-based magnonic devices operating at the nanometer scale.

19.
Sensors (Basel) ; 22(13)2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35808324

RESUMO

Several studies have already analysed power output in running or the relation between VO2max and power production as factors related to running economy; however, there are no studies assessing the difference in power output between shod and barefoot running. This study aims to identify the effect of footwear on the power output endurance runner. Forty-one endurance runners (16 female) were evaluated at shod and barefoot running over a one-session running protocol at their preferred comfortable velocity (11.71 ± 1.07 km·h−1). The mean power output (MPO) and normalized MPO (MPOnorm), form power, vertical oscillation, leg stiffness, running effectiveness and spatiotemporal parameters were obtained using the Stryd™ foot pod system. Additionally, footstrike patterns were measured using high-speed video at 240 Hz. No differences were noted in MPO (p = 0.582) and MPOnorm (p = 0.568), whereas significant differences were found in form power, in both absolute (p = 0.001) and relative values (p < 0.001), running effectiveness (p = 0.006), stiffness (p = 0.002) and vertical oscillation (p < 0.001). By running barefoot, lower values for contact time (p < 0.001) and step length (p = 0.003) were obtained with greater step frequency (p < 0.001), compared to shod running. The prevalence of footstrike pattern significantly differs between conditions, with 19.5% of runners showing a rearfoot strike, whereas no runners showed a rearfoot strike during barefoot running. Running barefoot showed greater running effectiveness in comparison with shod running, and was consistent with lower values in form power and lower vertical oscillation. From a practical perspective, the long-term effect of barefoot running drills might lead to increased running efficiency and leg stiffness in endurance runners, affecting running economy.


Assuntos
Corrida , Sapatos , Fenômenos Biomecânicos , Feminino , , Marcha , Humanos , Estado Nutricional
20.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1421079

RESUMO

ABSTRACT Introduction: De Garengeot hernia is an entity mainly diagnosed intraoperatively. It is more frequently observed in women and is defined as the presence of the vermiform appendix inside to femoral hernia. Most femoral hernias are identified based on clinical diagnosis, but diagnostic imaging is necessary for confirmation. Ultrasound, for example, is a valuable tool to characterize the anatomy of the hernia and its content, and to establish surgical planning. Case presentation: A 75-year-old woman attended the general surgery department of a high complexity hospital in Bogotá, Colombia, due to a painful mass in the right inguinal region. The initial ultrasound study showed a femoral hernia containing the incarcerated appendix and periappendiceal fluid in the hernial sac. The patient developed chronic appendiceal inflammation, so she underwent femoral hernia repair with mesh and appendectomy without complications, achieving a satisfactory recovery. Conclusion: Clinical examination may be sufficient to confirm the presence of a hernia in a large number of cases when the diagnostic approach involves the search of inguinal masses with pain. However, to facilitate surgical planning, diagnostic imaging, especially ultrasound with high-resolution transducers, is the primary tool to characterize the type of hernia and the contents of the hernial sac.


RESUMEN Introducción. La hernia de Garengeot es una entidad cuyo diagnóstico es principalmente intraoperatorio, se presenta con mayor frecuencia en mujeres y corresponde al hallazgo del apéndice cecal contenido en una hernia femoral. La mayoría de las hernias femorales se identifican mediante diagnóstico clínico, pero para su verificación es importante hacer una valoración con imágenes diagnósticas: el ultrasonido, por ejemplo, es una herramienta valiosa para caracterizar la anatomía de la hernia y su contenido, y para establecer el planeamiento quirúrgico. Presentación de caso. Mujer de 75 años quien asistió al servicio de cirugía general de un hospital de alta complejidad de Bogotá, Colombia, por presentar una masa dolorosa en región inguinal derecha. El estudio ecográfico inicial mostró una hernia femoral conteniendo el apéndice cecal con septos internos que separaban el líquido dentro del saco herniario. La paciente presentó inflamación crónica en el apéndice, por lo que se le practicó herniorrafía femoral con malla y apendicectomía sin complicaciones y con las cuales tuvo una recuperación satisfactoria. Conclusiones. El examen clínico puede ser suficiente para confirmar la presencia de una hernia en un gran número de casos cuando se hace el abordaje diagnóstico de masas inguinales con presencia de dolor; sin embargo, las imágenes diagnósticas, especialmente la ecografía con transductores de alta resolución, constituyen la herramienta de primera línea para caracterizar el tipo de hernia y el contenido del saco herniario, lo que facilita la planeación quirúrgica.

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