Evaluation method of dynamic postural stability for functional ankle instability based on acceleration signals / 中国康复理论与实践

ObjectiveTo compare the retest reliability and discriminant validity of dynamic postural stability indices for functional ankle instability (FAI) obtained by different algorithms based on acceleration signals at different positions of human body. MethodsFrom April to June, 2021, 21 subjects with unilateral FAI and 21 subjects with normal ankle were recruited. Three inertial sensors were attached to the waist points, knee and ankle positions. The ground reaction force (GRF) and kinematics data of the subjects in multi-direction single leg landing test were collected synchronously by 3D force plate and inertial sensors. The unbounded third order polynomial (UTOP) fitting method was used to calculate the stability time, and the root mean square was used to caculate the stability index. ResultsMost of the indicators calculated based on acceleration signal correlated with that based on GRF with low coefficient (|r| = 0.116 to 0.368, P < 0.05). The stability time and stability index based on the acceleration signals of different positions of human body showed low to high retest reliability (CMC 0.30 to 0.91). For the females, among the stability time based on acceleration signal, eleven indexes achieved average to very high discriminant validity (AUC = 0.702 to 0.942, P < 0.05); eight of the stability indexes reached general level of discriminant validity (AUC = 0.717 to 0.782, P < 0.05). No algorithms achieved good discriminant effect in male subjects. ConclusionBased on the acceleration signal of waist point in single-leg landing stability test, the stability time calculated by UTOP algorithm can evaluate the dynamic postural stability of female FAI patients with high discriminant validity and medium to high retest reliability.

Differences in Neck Injuries of Dummy Models at Different Backrest Angles under Horizontal Negative Acceleration / 医用生物力学

Objective Based on the dummy model, to study the relationship between different backrest angles and neck injuries under the effect of horizontal negative acceleration (-Gx ). Methods The dummy model was fixed on the base of the acceleration platform facing the orbital direction, and the backrest angle was set at 17°, 22°, 30°, respectively. Each experimental group performed 10 repeated tests according to the same acceleration curve, differences between the upper and lower acceleration of the cervical spine under the same -Gx conditions were compared, and the neck injury criteria (NIC) was calculated and compared through curve fitting. Results The time-acceleration curves of the upper and lower cervical spine in the anteroposterior and vertical directions had the same shape with peak differences. In the anteroposterior direction (X-axis), the acceleration peak of the 22° backrest angle experimental group was slightly higher than that of 17° and 30° backrest angle experimental groups, but in the vertical direction (Z-axis), the acceleration peak of the 22° backrest experimental group was lower than that of 17° and 30° backrest angle experimental groups. In the anteroposterior and vertical directions, the NICmax measured by 22° backrest angle experimental group was relatively smaller, NICmax measured by 30°backrest angle experimental group was in the middle, and NICmax measured by 30° backrest angle experimental group was relatively larger. Conclusions There was a nonlinear relationship between the backrest angle and theneck injury. The neck injury of the dummy model with the backrest angle of 22° was smallest under the effect of-Gx in this experiment.

The Mechanism of Brain Injury Induced by Rotational Motion / 医用生物力学

Traumatic brain injury ( TBI ) has caused serious economic and social burdens, but due to its heterogeneity, there is no effective treatment. In TBI with different severity, diffuse axonal injury (DAI) incidenceis high. The investigation on DAI will contribute to the diagnosis and treatment of TBI. In this study, the classification of TBI and the research status of DAI were summarized. The method to judge the severity of TBI and DAI, and animal experimental models and related injury criteria and thresholds were reviewed. The result show that DAI is mainly generated by rotational acceleration and it is related to angular acceleration, angular velocity and duration. Several TBI animal models can induce the pathology of DAI, and inertial rotation models which can produce only rotational acceleration have been developed. However, these models are instantaneous rotation models, and the rotation duration is uncontrollable, thus a longer duration is impossible, and DAI severity under long rotational motion cannot be studied. The study proposes that a new rotation animal model which can control rotation duration should be developed. The development of the animal model and investigation on pathomechanism of the model will contribute to the prevention and treatment of DAI.

The relationship between jumping and sprinting performance in teenage sprinters / Relación entre el desempeño del salto y el sprint en velocistas adolescentes / Relação entre o desempenho de salto e sprint em velocistas adolescentes

ABSTRACT Objectives: This study aimed to examine the relationship between vertical jumping at forces of specific time phase and sprint performance in teenage sprinters. Methods: Fifteen male teenage sprinters (age: 14±2 years, height: 168±2 cm, weight: 61±1 kg) participated in the study. The subjects performed the following bilateral/unilateral jumps on a force platform: a) squat jump (SJ), b) unilateral SJ (USJ), c) 40cm drop jump (DJ), and d) 20cm unilateral DJ (UDJ). The 60m sprint test was administered on the second day. Brower split timers were positioned to record subjects' 5m, 10m, 50m and 60m split times. The variables for inclusion were vertical jump height, maximum force, and force output at 120ms in all jumps and sprint time measures. Results: The results of the Pearson Product Moment Correlation analysis showed that SJ120ms was correlated to 5m and USJ120ms was correlated to 10m. UDJ120ms showed a stronger correlation with 50m than DJ120ms. Although significant correlations using maximum force and height were observed, there were inconsistent results between bilateral and unilateral jumps. Conclusion: Our results highlighted that jumps that have similar form with certain force outputs at specific event timing could more precisely predict sprint performance in teenage sprinters. USJ120ms and UDJ120ms could better predict the acceleration (10m) and high-speed phase (50m) in sprint performance, respectively. Moreover, coaches and practitioners should be cautious when using only jump height or maximum force to predict sprint performance, since the results could be inaccurate when specific movement variables are not thoughtfully considered. Level of evidence III.

RESUMEN Objetivos: Este estudio tuvo como objetivo examinar la relación entre el salto vertical y la fuerza en tiempo específico y el desempeño del sprint en velocistas adolescentes. Métodos: Participaron en el estudio quince adolescentes varones velocistas (edades: 14 ± 2 años, estatura: 168 ± 2 cm, peso: 61 ± 1 kg). Los individuos realizaron los siguientes saltos bilaterales y unilaterales en una plataforma de fuerza: a) squat jump (SJ), b) SJ unilateral (USJ), c) drop jump (DJ) de 40 cm e d) DJ unilateral (UDJ) de 20 cm. La prueba de sprint de 60 m se realizó el segundo día. Los cronómetros en el entrenamiento fraccionado se ajustaron para registrar tiempos de 5 m, 10 m, 50 m y 60 m. Las variables que se incluyeron fueron la altura del salto vertical, la fuerza máxima y la salida de fuerza a 120 m en todos los saltos y mediciones del tiempo del sprint. Resultados: Los resultados del análisis de correlación producto-tiempo de Pearson revelaron que el SJ de 120 m estaba correlacionado con 5 m y el USJ de 120 m estaba correlacionado con 10 m. El UDJ de 120 m tuvo una mayor correlación con el DJ de 50 m que con el de 120 m. Aunque se observaron correlaciones significativas con la fuerza y la altura máximas, algunos resultados fueron inconsistentes entre los saltos bilaterales y unilaterales. Conclusiones: Nuestros resultados pusieron de manifiesto que los saltos con una forma similar a determinadas salidas de fuerza en un tiempo específico del evento pueden predecir con mayor precisión el desempeño en el sprint en adolescentes velocistas. El USJ de 120 m y el UDJ de 120 m pueden predecir mejor, respectivamente, la aceleración (10 m) y la fase de alta velocidad (50 m) en el desempeño del sprint. Además, los entrenadores y practicantes deben ser cautelosos a la hora de utilizar únicamente la altura del salto o la fuerza máxima para predecir el desempeño en el sprint, ya que los resultados pueden ser inexactos cuando no se tienen en cuenta con precisión las variables específicas del movimiento. Nivel de evidencia III.

RESUMO Objetivos: Este estudo teve como objetivo examinar a relação entre o salto vertical e a força em tempo específico e o desempenho de sprint em velocistas adolescentes. Métodos: Quinze adolescentes velocistas do sexo masculino (idade: 14 ± 2 anos, estatura: 168 ± 2 cm, peso: 61 ± 1 kg) participaram do estudo. Os indivíduos realizaram os seguintes saltos bilaterais e unilaterais em uma plataforma de força: a) squat jump (SJ), b) SJ unilateral (USJ), c) drop jump (DJ) de 40 cm e d) DJ unilateral (UDJ) de 20cm. O teste de sprint de 60 m foi realizado no segundo dia. Os cronômetros rastreadores para treinos fracionados foram posicionados para registrar os tempos fracionados de 5 m, 10 m, 50 m e 60 m. As variáveis para inclusão foram altura do salto vertical, força máxima e saída de força a 120 m em todos os saltos e medidas de tempo do sprint. Resultados: Os resultados da análise da correlação produto-tempo de Pearson mostraram que o SJ de 120 m foi correlacionado com 5 m e USJ de 120 m foi correlacionado com 10 m. O UDJ de 120 m teve correlação mais forte com DJ de 50 m do que de 120 m. Embora tenham sido observadas correlações significativas com força e altura máximas, alguns resultados foram inconsistentes entre os saltos bilaterais e unilaterais. Conclusões: Nossos resultados destacaram que os saltos com forma semelhante a certas saídas de força no tempo específico do evento podem prever com mais precisão o desempenho no sprint em adolescentes velocistas. O USJ de 120 m e o UDJ de 120 m podem prever melhor, respectivamente, a aceleração (10 m) e a fase de alta velocidade (50 m) no desempenho no sprint. Além disso, treinadores e praticantes devem ser cautelosos ao usar apenas a altura do salto ou a força máxima para prever o desempenho no sprint, uma vez que os resultados podem ser imprecisos quando variáveis específicas do movimento não forem consideradas com precisão. Nível de evidência III.

Reconstruction and Quantitative Evaluation of Blunt Injury Cases by Finite Element Method / 法医学杂志

OBJECTIVES@#To reconstruct the cases of acceleration craniocerebral injury caused by blunt in forensic cases by finite element method (FEM), and to study the biomechanical mechanism and quantitative evaluation method of blunt craniocerebral injury.@*METHODS@#Based on the established and validated finite element head model of Chinese people, the finite element model of common injury tool was established with reference to practical cases in the forensic identification, and the blunt craniocerebral injury cases were reconstructed by simulation software. The cases were evaluated quantitatively by analyzing the biomechanical parameters such as intracranial pressure, von Mises stress and the maximum principal strain of brain tissue.@*RESULTS@#In case 1, when the left temporal parietal was hit with a round wooden stick for the first time, the maximum intracranial pressure was 359 kPa; the maximum von Mises stress of brain tissue was 3.03 kPa at the left temporal parietal; the maximum principal strain of brain tissue was 0.016 at the left temporal parietal. When the right temporal was hit with a square wooden stick for the second time, the maximum intracranial pressure was 890 kPa; the maximum von Mises stress of brain tissue was 14.79 kPa at the bottom of right temporal lobe; the maximum principal strain of brain tissue was 0.103 at the bottom of the right temporal lobe. The linear fractures occurred at the right temporal parietal skull and the right middle cranial fossa. In case 2, when the forehead and left temporal parietal were hit with a round wooden stick, the maximum intracranial pressure was 370 kPa and 1 241 kPa respectively, the maximum von Mises stress of brain tissue was 3.66 kPa and 26.73 kPa respectively at the frontal lobe and left temporal parietal lobe, and the maximum principal strain of brain tissue was 0.021 and 0.116 respectively at the frontal lobe and left temporal parietal lobe. The linear fracture occurred at the left posterior skull of the coronary suture. The damage evaluation indicators of the simulation results of the two cases exceeded their damage threshold, and the predicted craniocerebral injury sites and fractures were basically consistent with the results of the autopsy.@*CONCLUSIONS@#The FEM can quantitatively evaluate the degree of blunt craniocerebral injury. The FEM combined with traditional method will become a powerful tool in forensic craniocerebral injury identification and will also become an effective means to realize the visualization of forensic evidence in court.

Automatic Identification of Brain Injury Mechanism Based on Deep Learning / 法医学杂志

OBJECTIVES@#To apply the convolutional neural network (CNN) Inception_v3 model in automatic identification of acceleration and deceleration injury based on CT images of brain, and to explore the application prospect of deep learning technology in forensic brain injury mechanism inference.@*METHODS@#CT images from 190 cases with acceleration and deceleration brain injury were selected as the experimental group, and CT images from 130 normal brain cases were used as the control group. The above-mentioned 320 imaging data were divided into training validation dataset and testing dataset according to random sampling method. The model classification performance was evaluated by the accuracy rate, precision rate, recall rate, F1-value and AUC value.@*RESULTS@#In the training process and validation process, the accuracy rate of the model to classify acceleration injury, deceleration injury and normal brain was 99.00% and 87.21%, which met the requirements. The optimized model was used to test the data of the testing dataset, the result showed that the accuracy rate of the model in the test set was 87.18%, and the precision rate, recall rate, F1-score and AUC of the model to recognize acceleration injury were 84.38%, 90.00%, 87.10% and 0.98, respectively, to recognize deceleration injury were 86.67%, 72.22%, 78.79% and 0.92, respectively, to recognize normal brain were 88.57%, 89.86%, 89.21% and 0.93, respectively.@*CONCLUSIONS@#Inception_v3 model has potential application value in distinguishing acceleration and deceleration injury based on brain CT images, and is expected to become an auxiliary tool to infer the mechanism of head injury.

Logistic Regression Analysis of the Mechanism of Blunt Brain Injury Inference Based on CT Images / 法医学杂志

OBJECTIVES@#To study the correlation between CT imaging features of acceleration and deceleration brain injury and injury degree.@*METHODS@#A total of 299 cases with acceleration and deceleration brain injury were collected and divided into acceleration brain injury group and deceleration brain injury group according to the injury mechanism. Subarachnoid hemorrhage (SAH) and Glasgow coma scale (GCS), combined with skull fracture, epidural hematoma (EDH), subdural hematoma (SDH) and brain contusion on the same and opposite sides of the stress point were selected as the screening indexes. χ2 test was used for primary screening, and binary logistic regression analysis was used for secondary screening. The indexes with the strongest correlation in acceleration and deceleration injury mechanism were selected.@*RESULTS@#χ2 test showed that skull fracture and EDH on the same side of the stress point; EDH, SDH and brain contusion on the opposite of the stress point; SAH, GCS were correlated with acceleration and deceleration injury (P<0.05). According to binary logistic regression analysis, the odds ratio (OR) of EDH on the same side of the stress point was 2.697, the OR of brain contusion on the opposite of the stress point was 0.043 and the OR of GCS was 0.238, suggesting there was statistically significant (P<0.05).@*CONCLUSIONS@#EDH on the same side of the stress point, brain contusion on the opposite of the stress point and GCS can be used as key indicators to distinguish acceleration and deceleration injury mechanism. In addition, skull fracture on the same side of the stress point, EDH and SDH on the opposite of the stress point and SAH were relatively weak indicators in distinguishing acceleration and deceleration injury mechanism.

Clinical Investigation of Key Parameter Range of AMG Muscle Relaxant Monitor / 中国医疗器械杂志

The accelerometry(AMG) muscle relaxant monitor is the most widely used quantitative muscle relaxant monitor to assess the degree of neuromuscular at present. In this study, the ulnar nerve was stimulated by using train of four stimulation(TOF) mode of the AMG muscle relaxant monitor, and the movement of the adductor pollicis muscle was monitored. In this way, the distribution range of key parameters (acceleration peak value, response time, and TOF ratio) of the adductor pollicis muscle during the use of muscle relaxant in clinical practice is analyzed and will provide a practical basis for the development and improvement of the muscle relaxant monitor.

Heart rate extraction algorithm based on adaptive heart rate search model / 生物医学工程学杂志

Photoplethysmography (PPG) is a non-invasive technique to measure heart rate at a lower cost, and it has been recently widely used in smart wearable devices. However, as PPG is easily affected by noises under high-intensity movement, the measured heart rate in sports has low precision. To tackle the problem, this paper proposed a heart rate extraction algorithm based on self-adaptive heart rate separation model. The algorithm firstly preprocessed acceleration and PPG signals, from which cadence and heart rate history were extracted respectively. A self-adaptive model was made based on the connection between the extracted information and current heart rate, and to output possible domain of the heart rate accordingly. The algorithm proposed in this article removed the interference from strong noises by narrowing the domain of real heart rate. From experimental results on the PPG dataset used in 2015 IEEE Signal Processing Cup, the average absolute error on 12 training sets was 1.12 beat per minute (bpm) (Pearson correlation coefficient: 0.996; consistency error: -0.184 bpm). The average absolute error on 10 testing sets was 3.19 bpm (Pearson correlation coefficient: 0.990; consistency error: 1.327 bpm). From experimental results, the algorithm proposed in this paper can effectively extract heart rate information under noises and has the potential to be put in usage in smart wearable devices.

Characterizing the magnitude of vibration imposed by stochastic whole-body vibration platforms used in rehabilitation and training: a preliminary study / Caracterização da magnitude da vibração imposta por plataformas vibratórias estocásticas de corpo inteiro utilizadas em reabilitação e treinamento: estudo preliminar

Abstract The use of devices that produce stochastic whole-body vibration as a resource for rehabilitation and training programs has been founded on the theory of stochastic resonance. However, the prescription of rehabilitation and training programs must be preceded by the verification of imposed-vibration magnitude and of how it can be affected by the presence of an individual on the devices. The aim of this research was to characterize and analyze the effect of an individual's mass on the vibratory stimulus provided by stochastic whole-body vibration (SWBV) devices. The sample consisted of 30 repetitions for each one of the 6 vibration levels of the SWBV device (level 02, 04, 06, 08, 10 and 12), performed in two experimental situations (Without Load; Load [70Kg]; ≈ 35 kg on the right and left surfaces of the platform). For the antero-posterior, latero-lateral, and vertical directions, all variables showed significant differences between treatments, levels and interaction between experimental factors (p<.05), except for the Disp variable between treatments (p=.075). To measure vibration magnitude, a triaxial accelerometer was attached at the center of the board of one of the platform surfaces. Load interferes with parameters of vibration imposed by SWBV platforms, increasing ARMS and APEAK in the latero-lateral and antero-posterior directions, reducing these same parameters in the vertical direction.

Resumo O uso de dispositivos que produzem vibração estocástica de corpo inteiro como recurso para programas de reabilitação e treinamento foi fundamentado na teoria da ressonância estocástica. Entretanto, a prescrição de programas de reabilitação e treinamento deve ser precedida da verificação da magnitude da vibração imposta e de como ela pode ser afetada pela presença de um indivíduo nos dispositivos. O objetivo deste estudo foi caracterizar e analisar o efeito da massa do indivíduo sobre o estímulo vibratório proporcionado por dispositivos de vibração estocástica de corpo inteiro. A amostra consistiu em 30 repetições para cada um dos 6 níveis de vibração de um dispositivo de vibração estocástica de corpo inteiro (nível 02, 04, 06, 08, 10 e 12), realizados em duas situações experimentais (Sem carga e Carga [70Kg], 35 kg nas superfícies direita e esquerda da plataforma). Para medir a magnitude da vibração, um acelerômetro triaxial foi fixado ao centro do assoalho de uma das superfícies da plataforma. Para os eixos ântero-posterior, látero-lateral e vertical, todas as variáveis mostraram diferenças entre tratamentos, níveis e interação entre fatores experimentais (p<.05), exceto para a variável de deslocamento pico - a - pico (Disp) entre tratamentos (p=.075). A carga interfere com parâmetros de vibração impostos sobre as plataformas de vibração estocástica de corpo inteiro, aumentando a aceleração média (ARMS) e de pico (APEAK) nas direções látero-lateral e ântero-posterior, reduzindo estes mesmos parâmetros na direção vertical.

Does the change of direction deficit measure the time of change of direction?

Abstract Aim: To determine whether the change of direction (COD) deficit can represent the time of the change of direction in professional under 17 years old (U-17) soccer players. Methods: Sixteen young soccer athletes performed the adapted 505 agility test with the stationary stance (2 straight lines of 5 m) and the 10 m linear running test (LR). In both tests, the partial and total times were recorded every 2.5 m by time gates (0-2.5 m; 2.5-7.5 m; 7.5-10 m). The best performances were recorded and used to determine the COD deficit (difference between the time for the LR and 505 tests). The paired t-test compared the initial acceleration (0-2.5 m) time, the COD time (2.5-7.5 m), and the COD deficit among the tests. Results: Times in the LR test were significantly shorter in the initial acceleration phase (0-2.5 m), and the change of direction deficit was also lower than the change of direction time (2.5-7.5 m) for both sides (p = 0.005). Conclusion: When an athlete is aware of an upcoming change of direction, a lower initial acceleration results in biases for determining the change of direction deficit. Therefore, acceleration capacity might not be suitable to assess using the 505 agility test.

COVID-19 epidemic curve in Brazil: a sum of multiple epidemics, whose inequality and population density in the states are correlated with growth rate and daily acceleration. An ecological study

ABSTRACT Background: The epidemic curve has been obtained based on the 7-day moving average of the events. Although it facilitates the visualization of discrete variables, it does not allow the calculation of the absolute variation rate. Recently, we demonstrated that the polynomial interpolation method can be used to accurately calculate the daily acceleration of cases and deaths due to COVID-19. This study aimed to measure the diversity of epidemic curves and understand the importance of socioeconomic variables in the acceleration, peak cases, and deaths due to COVID-19 in Brazilian states. Methods: Epidemiological data for COVID-19 from federative units in Brazil were obtained from the Ministry of Health's website from February 25 to July 11, 2020. Socioeconomic data were obtained from the Instituto Brasileiro de Geografia e Estatística (https://www.ibge.gov.br/). Using the polynomial interpolation methods, daily cases, deaths and acceleration were calculated. Moreover, the correlation coefficient between the epidemic curve data and socioeconomic data was determined. Results: The combination of daily data and case acceleration determined that Brazilian states were in different stages of the epidemic. Maximum case acceleration, peak of cases, maximum death acceleration, and peak of deaths were associated with the Gini index of the gross domestic product of Brazilian states and population density but did not correlate with the per capita gross domestic product of Brazilian states. Conclusions: Brazilian states showed heterogeneous data curves. Population density and socioeconomic inequality were correlated with a more rapid exponential growth in new cases and deaths.

Viés da Escalada, Daemons de Otimização, e a Influência da Narrativa Social Aceleracionista / Hill-Climbing Bias, Optimization Daemons, and the Influence of Accelerated Social Narratives

O fenômeno de aceleração social, intimamente ligado a nossa modernização tecnológica e os sistemas políticos e sociais que adotamos, vem sendo alvo de questionamentos por parte da teoria crítica por diversos filósofos e sociólogos, principalmente em relação a se tal "aceleração" seja algo que, possa ser justificável pelo bem comum da sociedade. De fato, as rápidas mudanças que ocorreram no último século causaram uma tremenda mudança em nossos estilos-de-vida, e na maneira como experienciamos o mundo. Que a nossa sociedade mudou e continua a mudar é um fato evidente quando olhamos criticamente para o passado e presente, e comparamos diferentes épocas da história humana. Neste ensaio tentaremos explorar algumas possíveis hipóteses que fundamentem o comportamento aceleracionista em certos fatores e mecanismo biológicos que caracterizam os sistemas de motivação e saciação humanos. Também tentaremos mostrar como certos fenômenos sociais podem auxiliar em fortalecer este tipo de comportamento, e suas possíveis origens evolutivas. Este estudo tem como objetivo principal fundamentar a Tese Aceleracionista em evidências neurofisiológicas, cognitivo-comportamentais, evolutivas e sociais.

The phenomenon of social acceleration is closely linked to our technological modernization and the political and social systems we have adopted, and it has been questioned by several philosophers and sociologists, especially in relation to whether such acceleration is something that can be justified for the common good of society. In fact, the rapid changes that have occurred in the last century have caused a tremendous change in our lifestyles, and in the way we experience the world. That society have changed and continues to change is an evident fact when we look critically to the past and our present and compare different times in human history. In this essay we will try to explore some possible hypotheses that underpin accelerated behavior, in certain biological factors and mechanisms that characterize human motivation and satiation systems. We will also try to show how certain social phenomena can help to strengthen this type of behavior, and its possible evolutionary origins. The main objective of this study is to base the Accelerationist Thesis on neurophysiological, cognitive-behavioral, evolutionary and also social evidence.

Correlação entre o tempo de aceleração plantar, o índice tornozelo braquial e os escores SVS-WIfI em pacientes com isquemia crônica ameaçadora do membro / Plantar acceleration time correlates with WIfI stages in both non-diabetic and diabetic patients with chronic limb threatening ischemia

RESUMO Introdução: A avaliação hemodinâmica dos membros pelo índice tornozelo-braquial (ITB) em pacientes diabéticos com isquemia crônica ameaçadora dos membros pode estar falsamente elevada devido à calcinose da camada média das artérias. Alternativas como medidas de pressão do dedo do pé, pressão transcutânea de oxigênio (TCPO2) ou pletismografia não estão disponíveis na maioria das unidades vasculares no mundo. Uma nova abordagem diagnóstica por meio da análise espectral do fluxo ao Doppler na artéria plantar lateral do pé mostrou correlação com o grau de isquemia do membro e os estágios de risco de amputação do sistema de classificação (SVS-WIfI). Objetivo: Determinar a acurácia do Tempo de Aceleração Plantar (TAP) em relação ao Índice Tornozelo-Braquial (ITB) e os estágios de risco de amputação do sistema de classificação SVS-WIfI em pacientes com isquemia crônica ameaçadora do membro (Chronic Limb Threatening Ischemia-CLTI). Métodos: Estudo transversal realizado na Unidade de Cirurgia Vascular do Hospital Universitário Risoleta Tolentino Neves, Brasil, entre junho de 2019 e março de 2020, incluindo pacientes maiores de 18 anos, portadores de CLTI. Os dados coletados nos prontuários foram: dados demográficos, comorbidades, ITB e mensuração do TAP. Os indivíduos foram categorizados em três graus com base no ITB (ITB <0,8; ITB <0,6; ITB <0,4) e dois graus com base no risco de amputação (1-muito baixo e baixo; 2- moderado e alto), de acordo com a Classificação SVS-WIfI. A correlação do ITB e do risco de amputação com o TAP foi feita por meio da correlação de Spearman. Sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e acurácia também foram calculados através das curvas ROC (Receiver Operator CharacCurves) Resultados: Cento e oitenta e quatro pacientes consecutivos (265 membros inferiores) foram encaminhados para exame de ultrassonografia vascular com Doppler do membro inferior. 141 pacientes (74 diabéticos e 67 não diabéticos), 198 membros inferiores (104 diabéticos e 94 não diabéticos) atenderam aos critérios e foram incluídos para análise. O TAP correlacionou-se significativamente com o ITB e o risco de amputação (P <0,001) em ambos os grupos. A acurácia do TAP para detectar ITB<0,8 foi de até 91% no grupo diabético e 85% no grupo não diabético. Da mesma forma, para o diagnóstico de ITB<0,6 em pacientes diabéticos, observamos uma acurácia de 79% e em não diabéticos essa acurácia foi de 85%. Para detectar um ITB inferior a 0,4, a acurácia atingiu 88% em pacientes diabéticos e 87% em não diabéticos. No grupo diabético e não diabético, a acurácia do PAT para detectar SVS de risco moderado e alto de amputação atingiu 77%. O TAP se correlacionou com precisão com o ITB e os escores SVS-WifI. Conclusões: O tempo de aceleração plantar demonstrou alta correlação com o ITB e os estágios de classificação de isquemia e risco de amputação do sistema de classificação SVS-WIfI com alta sensibilidade, especificidade e acurácia em pacientes com isquemia crônica com risco de membro.

ABSTRACT Introduction: Limb hemodynamic evaluation through ankle-brachial index (ABI) in diabetic patients with chronic limb threatening ischemia may be falsely elevated due to the calcinosis of the arteries media layer. Alternatives as toe pressure measurements, transcutaneous oxygen pressure (TCPO2) or plethysmography are not readily available in most of the vascular units in the world. A new diagnostic approach through Spectral Doppler analysis of the flow in the lateral plantar artery of the foot has shown correlation with the grade of the limb ischemia and amputation risk stages of the Wound, Ischemia, and foot Infection (WIfI) classification system and ABI. Objective: to determine the accuracy of Plantar Acceleration Time (TAP) compared to the Ankle-Brachial Index (ABI) and the amputation risk stages of the SVS-WIfI classification system in patients with chronic limb threatening ischemia (CLTI). Methods: a cross-sectional study at the Vascular Surgery Unit at the university Hospital Risoleta Tolentino Neves, in Brazil, between June 2019 and March 2020, included patients >18 years, with CLTI. Data collected from medical records were demographics, comorbidities, ABI and measurement of TAP. Individuals were categorized in three degrees based on their ABI (ABI < 0,8; ABI < 06; ABI <0,4) and two degrees based on their amputation risk (1-very low and low; 2- moderate and high), according to SVS-WIfI classification. The correlation of ABI and amputation risk with TAP was made through Spearman's correlation. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were also calculated using receiver operator characteristic (ROC) curves Results: A hundred eighty-four consecutive patients (265 lower limbs) were referred to the vascular imaging unit for an arterial lower limb vascular ultrasound examination. 141 patients (74 diabetic and 67 non-diabetic), 198 lower limbs (104 diabetic and 94 non-diabetic) met the criteria and were included for analysis. Plantar Acceleration Time correlated significantly with ABI and amputation risk (P < 0.001) in both groups. The accuracy of PAT to detect ABI<0.8 was up to 91% in diabetic group and 85% in non-diabetic group. Likewise, for diagnosing ABI <0.6 in diabetic patients, we observed an accuracy of 79% and in non-diabetics this accuracy was 85%. To detect an ABI lower than 0.4, the accuracy reached 88% in diabetic patients and 87% in non-diabetics. In the diabetic and non-diabetic group, the accuracy of PAT to detect moderate and high amputation risk WIfI SVS reached 77%. PAT accurately correlates with ABI and WIfI-SVS scores. Conclusions: Measurement of the Plantar Acceleration Time demonstrates high correlation with ABI and the Ischemia grading and amputation risk stages of the SVS-WIfI classification system with high sensitivity, specificity and accuracy in patients with chronic limb threatening ischemia.

Effects of gantry acceleration limitations on VMAT plans / 中华放射医学与防护杂志

Objective:To study the effects of gantry acceleration limitations of a linear accelerator (linac) on the dosimetry of volumetric modulated arc therapy (VMAT) plans, machine efficiency, and dose verification result of VMAT plans and to explore the optimal selection of gantry motion models in the Pinnacle treatment planning system.Methods:Ten cases of nasopharyngeal carcinoma, non-small cell lung cancer, sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, and invasive ductal carcinoma of the breast were each selected for this study. Then two models were set up in the Pinnacle v9.10 treatment planning system, namely the one allowing gantry acceleration and the one limiting gantry acceleration. The same field arrangement, optimized target parameters, and optimized weights of VMAT plans were adopted in the two models, in order to analyze the dosimetric variations in targets and organs at risk (OARs) and compare the differences in treatment time and gamma passing rates.Results:The treatment time of the enrolled patients under the model allowing gantry acceleration was significantly lower than that of the patients under the model limiting gantry acceleration was adopted ( t=-6.751, -0.209, -19.523, -28.999; P< 0.05) and decreased by 15.27%, 18.07%, 19.71%, and 28.75%, respectively. Meanwhile, the conformity and uniformity of target areas were affected, while there was no statistical significance in the gamma passing rates in the validation of VMAT plans ( P>0.05). For the cases of nasopharyngeal carcinoma (NPC), the maximum dose to brainstem PRV increased by 1.25%. For the cases of lung cancer, the maximum dose to the spinal cord and lung V20 increased by 1.19% and 1.21%, respectively, while lung V5 decreased by 1.21%. For the cases of sigmoid adenocarcinoma with retroperitoneal lymph node metastasis, the mean doses to bilateral kidneys, livers, small intestine, and colon all increased. For the cases of breast cancer, lung V10 on the opposite side of cancer increased by 1.66% and the mean dose to the lungs on the same side of cancer decreased by 7.45%. Conclusions:The model allowing gantry acceleration allows the treatment time to be significantly shortened and the treatment efficiency improved. Although this model had the shortcomings such as affecting the conformity and uniformity of target areas to a certain extent and increasing the doses to some OARs, clinical requirements for dosimetry were still met. Therefore, it is recommended to use the model allowing gantry acceleration in the Pinnacle planning system.

Research on Reliability Index and Realization of Magnetic Resonance (MR) Based on Clinical Use Condition / 中国医疗器械杂志

Combined with the clinical use condition of MR in use in Shanghai Sixth People's Hospital, MR components are divided into scanning type I and scanning type II. At the same time, combined with the main loss force of MR components, the research divides MR components into dynamic components and electric thermal components. In this study, a complete set of MR system reliability indexes and implementation methods are given, including system reliability index determination, system reliability allocation, component reliability index realization, system reliability prediction and system reliability verification. At the same time, this study also gives the methods of reliability prediction and reliability verification, and gives the MTBF calculation method of MR system based on clinical use data statistics.

Optimization of Key Techniques for Maintaining Bus Voltage Stability in Variable Speed Turbine of Ventilator / 中国医疗器械杂志

OBJECTIVE@#To explore the optimization scheme of maintaining bus voltage stability during turbo-turbine acceleration and deceleration of ventilator.@*METHODS@#The ideal diode is used to replace the diode in the busbar power supply circuit, and a comparative discharge circuit is added to the busbar. When the busbar voltage is higher than the preset threshold, the comparator can be opened and the energy could be discharged through the power resistor.@*RESULTS@#When the turbine starts and stops rapidly, the optimized scheme can effectively reduce the bus impedance, and the discharge circuit can maintain the bus voltage fluctuation less than 2 V.@*CONCLUSIONS@#The optimization scheme proposed in this study can effectively improve the efficiency and stability of the turbine in the process of acceleration and braking, and provide reference for the design of the stability maintenance circuit of the ventilator turbine bus.

Relação entre inteligência, criatividade, personalidade e superdotação no contexto escolar / Association of intelligence, creativity, personality, and giftedness in the school context / Relación entre inteligencia, creatividad, personalidad y superdotación en el contexto escolar

As diferenças entre indivíduos superdotados e não superdotados vêm sendo alvo de muitos estudos e controvérsias. Este estudo teve como objetivo comparar alunos que ingressaram precocemente na universidade (grupo I), alunos que ingressaram na universidade no tempo regular (grupo II) e alunos superdotados do ensino médio (grupo III) a respeito da inteligência, criatividade e personalidade, bem como investigar a relação entre essas variáveis. Participaram do estudo 30 alunos (15 de cada sexo), com média de idade de 17,3 anos. Foram utilizados instrumentos de inteligência (Matrizes Progressivas de Raven), criatividade (Teste Torrance de Pensamento Criativo) e personalidade (Inventário Fatorial de Personalidade e Rorschach), e os dados foram tratados com análises não paramétricas de Kruskal-Wallis, Mann-Whitney e correlação de Spearman. Os resultados apontaram diferenças significativas em relação à inteligência (X² [2, N = 30] = 5,975; p = 0,05) e aos fatores de criatividade: fluência (X² [2, N = 30] = 6,302; p = 0,043) e flexibilidade (X² [2, N = 30] = 6,415; p = 0,040). Observou-se correlação positiva entre inteligência e o fator analogia (r s = 0,426; p = 0,019). Os alunos dos grupos I e III demonstraram vantagens nos fatores de inteligência e criatividade em relação aos do grupo II, e os do grupo I demonstraram ainda maior abertura a novas experiências e mudanças do que os alunos dos outros dois grupos. Os resultados apontam que inteligência e criatividade são construtos diferentes, mas relacionados, sugerindo que inteligência seria um subconjunto de criatividade.(AU)

Several studies have addressed the differences between gifted and non-gifted individuals, generating much controversy. This study aimed to investigate the association between intelligence, creativity, and personality, and compare these variables in three groups of students: group I, including early entrants to university; group II, including regular entrants; ang group III, high school students enrolled in a gifted program (group III). Thirty students (15 males and 15 females) with mean age of 17.3 years participated in the study. Intelligence was measured using the Raven's Progressive Matrices, creativity with the Torrance Test of Creative Thinking, and personality with the Factorial Personality Inventory and Rorschach. Data were analyzed using non-parametric Kruskal-Wallis, Mann-Whitney, and Spearman's correlations tests. The results showed significant differences regarding intelligence (X² [2, N = 30] = 5,975; p = 0,05) and the creative factors fluency (X² [2, N = 30] = 6,302; p = 0,043) and flexibility (X² [2, N = 30] = 6,415; p = 0,040), besides indicating a positive correlation between intelligence and analogy (r s = 0,426; p = 0,019). When compared to group II students, those of groups I and III showed advantages in intelligence and creativity. Moreover, group I students also showed a greater openness to new experiences and changes when compared to those of the two other groups. The results indicate that intelligence and creativity are different but related constructs, suggesting that intelligence would be a subset of creativity.(AU)

Las diferencias entre individuos superdotados y no superdotados son objeto de diversos estudios y controversias. Este estudio tuvo como objetivo comparar alumnos que ingresaron precozmente a la universidad (grupo I), alumnos que ingresaron a la universidad en el tiempo regular (grupo II), y alumnos superdotados de la secundaria (grupo III) en relación a inteligencia, creatividad y personalidad, así como investigar la relación entre esas variables. Participaron en el estudio 30 alumnos (15 de cada sexo) con edad media de 17,3 años. Los instrumentos utilizados fueron los de inteligencia (Matrices Progresivas de Raven), de creatividad (Test de Pensamiento Creativo de Torrance) y de personalidad (Cuestionario Factorial de Personalidad y Rorschach); para procesar los datos se utilizó pruebas no paramétricas de Kruskal-Wallis, de Mann-Whitney y la correlación de Spearman. Los resultados mostraron diferencias significativas en relación a inteligencia (X² [2, N = 30] = 5,975; p = 0,05) y en los factores de creatividad: fluencia (X² [2, N = 30] = 6,302; p = 0,043) y flexibilidad (X² [2, N = 30] = 6,415; p = 0,040). Hubo una correlación positiva entre inteligencia y el factor analogía (r s = 0,426; p = 0,019). Los estudiantes de los grupos I y III demostraron ventajas en los factores de inteligencia y creatividad en relación al grupo II, y los del grupo I mostraron mayor apertura a nuevas experiencias y cambios en comparación a los otros dos grupos. Los resultados indican que la inteligencia y la creatividad son constructos distintos pero relacionados, sugiriendo que la inteligencia sería un subconjunto de la creatividad.(AU)

Clinical and experimental knowledge of photobiomodulation in accelerated orthodontics: A review / Conocimiento clínico y experimental de la fotobiomodulación en ortodoncia acelerada: Una revisión

Background: In recentyears, there has been an increasing interest in finding a noninvasive method to induce the accelerationofdentalmovement,methodssuchaslowintensityvibrations,pulsedelectromagneticfields,andlow-level laser therapy (LLLT). There have been multiple studies on the efficacy of LLLT in animal models, in vitro and in patients without conclusiveresults. Objective: Evaluate the state of the art on the use of LLLT to increase the rate of the orthodontic tooth movement to create a concise reference guide of the different laser and protocols available. Materials and Methods: The authors searched electronic databases (MedLine, Scopus and Semantic Scholar) for articles that evaluated the effectsoflow-leverlasertherapyontheorthodontictoothmovement.Screeningwasperformedatthetitle/abstract and full-text level. Data extraction and quality assessment were performed by two reviewers independently. The reference lists of relevant studies were also screened for further relevantliterature. Results: We found conflicting information as to the efficacy of LLLT to accelerate the orthodontic tooth movement (OTM). There is no consensus in the way the irradiation should be performed. Conclusions: The lack of a standardized irradiation protocol makes it hard to compare conflicting results, even in cases where the laser have the same technical specifications.

Antecedentes: En los últimos años, ha habido un interés creciente en encontrar un método no invasivo para inducir la aceleración del movimiento dental, métodos como vibraciones de baja intensidad, campos electromagnéticos pulsados y terapia con láser de bajo nivel(LLLT). Se han realizado múltiples estudios sobre la eficacia de la LLLT en modelos animales, in vitro y en pacientes sin resultados concluyentes. Objetivo: Evaluar el estado del arte en el uso de LLLT para aumentar la velocidad del movimiento dental ortodóncico para crear una guía de referencia concisa de los diferentes láser y protocolos disponibles. Materiales y métodos: Los autores buscaron en bases de datos electrónicas (MedLine, Scopus y Semantic Scholar) artículos que evaluaran los efectos de la terapia con láser de baja intensidad sobre el movimiento dental ortodóncico. La selección se realizó a nivel de título / resumen y texto completo. Dos revisores realizaron de forma independiente la extracción de datos y la evaluación de la calidad. También se examinaron las listas de referencias de estudios relevantes para obtener más literatura significativa. Resultados:EncontramosinformacióncontradictoriaencuantoalaeficaciadelaLLLTparaacelerarel movimiento dental ortodóncico (OTM).No hay consenso sobre la forma en que se debe realizar lairradiación. Conclusiones: La falta de un protocolo de irradiación estandarizado dificulta la comparación de resultados, incluso en los casos en que el láser tiene las mismas especificaciones técnicas.