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Fundamentos: O aneurisma de aorta ascendente é uma doença silenciosa, com alta mortalidade, cujos fatores relacionados ao seu crescimento não são totalmente conhecidos. O padrão hemodinâmico na aorta ascendente aneurismática pode estar associado a um maior risco de complicação. O objetivo deste estudo foi identificar variáveis do escoamento sanguíneo, determinadas numericamente que poderiam estar associadas ao crescimento do aneurisma de aorta ascendente. Método: Estudo observacional, longitudinal, retrospectivo e unicêntrico. Modelos anatomia-específicos foram obtidos através de imagens de duas angiotomografias de aorta realizadas com intervalo de um a três anos. A partir de estudo numérico por fluidodinâmica computacional, buscou-se padrões de escoamento presentes na primeira angiotomografia associados ao crescimento do aneurisma (definido pelo aumento do volume da aorta ascendente em 5% ou mais), através dos testes qui-quadrado e Exato de Fisher. Admitiu-se erro alfa de 5% e consideraram-se significantes valores de p ≤ 0,05. Resultados: Trinta pacientes foram incluídos no estudo, dos quais 16 (53,3%) apresentaram crescimento do aneurisma. O crescimento do aneurisma foi associado às seguintes variáveis: alta pressão relativa na parede (≥ 100 Pa); alta tensão cisalhante na parede (≥ 7 Pa) combinada com alta pressão relativa; e carga de tensão cisalhante. Conclusão: Este estudo demonstrou associação entre as variáveis de alta pressão relativa e alta tensão cisalhante, obtidas através da fluidodinâmica computacional, e o crescimento do aneurisma de aorta ascendente(AU)

Background: Ascending aortic aneurysm is a silent disease, with high mortality, whose factors related to its growth are not fully known. The hemodynamic pattern in the ascending aorta may be associated with a higher risk of complications. The aim of this study was to identify blood flow variables, numerically obtained that could be related to ascending aortic aneurysm growth. Methods: Observational, longitudinal, single-center study. Specific anatomy models were obtained through images of two angiotomographies of the aorta performed one to three years apart. Based on a numerical study by computational fluid dynamics, flow patterns present in the first angiotomography associated with aneurysm growth (defined as an increase in the volume of the ascending aorta ≥ 5%) were sought, using the chi-square test and Fisher's exact test. An alpha error of 5% was admitted and p values ≤ 0.05 were considered significant. Results: 30 patients were included in the study, of which 16 (53.3%) had aneurysm growth. Aneurysm growth was related to: high relative pressure (≥ 100 Pa); high shear stress (≥ 7 Pa) in the intersection region with the high relative pressure region; and stress load over time. Conclusion: This study demonstrated an association between the variables of high relative pressure and high shear stress, obtained through computational fluid dynamics, and ascending aortic aneurysm growth(AU)

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O estudo investigou a melhoria da técnica de Desinfecção Solar de água (SODIS) pela adição de Azul de Metileno (AM), visando acelerar a descontaminação microbiológica de água, especialmente em regiões com baixa incidência solar. A água contaminada por microrganismos é uma das principais causas de doenças em países em desenvolvimento, e a desinfecção solar tem se mostrado eficaz, porém limitada em condições climáticas desfavoráveis. A inclusão do AM, um corante fotossensível, acelera o processo, gerando oxigênio reativo ao ser exposto à luz solar, o que inativa os microrganismos. O estudo foi dividido em três partes: in silico, in vitro e in vivo. No estudo in silico, foram realizadas simulações para prever a toxicidade aguda e a mutagenicidade do AM nas formas oxidada (azul) e reduzida (leuco). Ambas as formas apresentaram baixa toxicidade, com a forma leuco sendo ainda menos tóxica. A mutagenicidade foi observada na forma oxidada em alguns testes, mas a forma leuco se mostrou segura. Nos experimentos in vitro, foram analisadas amostras de água de poço artesiano, contaminadas com patógenos. A análise metagenômica identificou a presença de microbiota intestinal humana e animal, além de patógenos causadores de doenças graves. Após a aplicação do método AM/SODIS, houve uma redução significativa no número de microrganismos, comprovando a eficácia do tratamento na descontaminação da água. No estudo in vivo, camundongos foram expostos ao consumo de água tratada com AM/SODIS por 13 semanas. Após a análise de fígados e rins dos animais, não foram observadas alterações histopatológicas ou sinais de citotoxicidade, genotoxicidade ou mutagenicidade. A análise da expressão de proteínas relacionadas à morte celular também não indicou estresse celular, autofagia ou apoptose, sugerindo que o uso do AM na concentração de 100 ng/ml é seguro para consumo humano. Os resultados do estudo indicam que a combinação do SODIS com o AM melhora a eficiência do processo de desinfecção de água, tornando-o uma opção viável para uso em regiões com pouca insolação ou em situações de emergência. A técnica é simples, de baixo custo e pode ser aplicada em áreas carentes, contribuindo para a redução de doenças causadas por água contaminada. Além disso, o estudo não encontrou evidências de toxicidade significativa nas formas de AM utilizadas, tornando o método seguro para o consumo humano. A pesquisa contribui para o desenvolvimento de tecnologias de baixo custo para o tratamento de água, alinhando-se aos Objetivos de Desenvolvimento Sustentável da ONU, especialmente em relação ao acesso à água potável e saneamento. A aplicação da técnica em larga escala pode ajudar a mitigar os efeitos da falta de saneamento em comunidades vulneráveis, prevenindo doenças como diarreia, especialmente em crianças.(AU)

The study investigated the improvement of the Solar Water Disinfection (SODIS) technique through the addition of Methylene Blue (MB), aiming to accelerate the microbiological decontamination of water, especially in regions with low sunlight exposure. Microbiologically contaminated water is one of the leading causes of diseases in developing countries, and solar disinfection has proven effective but limited under unfavorable weather conditions. The inclusion of MB, a photosensitive dye, accelerates the process by generating reactive oxygen when exposed to sunlight, which inactivates microorganisms. The study was divided into three parts: in silico, in vitro, and in vivo. In the in silico study, simulations were conducted to predict the acute toxicity and mutagenicity of MB in its oxidized (blue) and reduced (leuco) forms. Both forms showed low toxicity, with the leuco form being even less toxic. Mutagenicity was observed in the oxidized form in some tests, but the leuco form was found to be safe. In the in vitro experiments, samples of artesian well water contaminated with pathogens were analyzed. Metagenomic analysis identified the presence of human and animal intestinal microbiota, as well as pathogens causing severe diseases. After applying the AM/SODIS method, there was a significant reduction in the number of microorganisms, demonstrating the efficacy of the treatment in water decontamination. In the in vivo study, mice were exposed to water treated with AM/SODIS for 13 weeks. After analyzing the liver and kidneys of the animals, no histopathological alterations or signs of cytotoxicity, genotoxicity, or mutagenicity were observed. The analysis of the expression of proteins related to cell death also indicated no cellular stress, autophagy, or apoptosis, suggesting that the use of MB at a concentration of 100 ng/ml is safe for human consumption. The study's results indicate that the combination of SODIS with MB improves the efficiency of the water disinfection process, making it a viable option for use in regions with low sunlight or emergency situations. The technique is simple, low-cost, and can be applied in underprivileged areas, helping to reduce waterborne diseases. Furthermore, the study found no significant toxicity in the MB forms used, making the method safe for human consumption. This research contributes to the development of low-cost technologies for water treatment, aligning with the United Nations Sustainable Development Goals, particularly regarding access to clean water and sanitation. The large-scale application of the technique could help mitigate the effects of poor sanitation in vulnerable communities, preventing diseases like diarrhea, especially in children.(AU)

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Objetivo:Investigar estudos que apresentem sistemas computacionais de auxílio à cicatrização de feridas e quais sistemas se referem ao uso de laser de baixa intensidade. Método: Revisão de escopo que visou responder à questão de pesquisa: Quais sistemas computacionais auxiliam na cicatrização de feridas? Uma subquestão foi: quais sistemas computacionais se referem ao uso do laser de baixa intensidade? Resultados: A partir da busca, aplicando os critérios de elegibilidade, 49 artigos compuseram a amostra final. Os sistemas apresentaram várias finalidades de apoio à cicatrização de feridas, em que a maioria apresentou como usuário do sistema o profissional de saúde, sendo a medicina a área profissional mais mencionada, embora a enfermagem esteja envolvida com o manejo do cuidado às pessoas com feridas. Foi relatada com frequência a inovação na assistência a partir do uso do sistema computacional, o que demonstra a importância desse tipo de ferramenta para a prática clínica. Verificou-se com frequência o uso de plataforma mobile, como tendência da atualidade. Conclusão: Os sistemas computacionais têm sido utilizados como ferramentas para apoiar pacientes e principalmente profissionais na cicatrização de feridas. Quanto ao laser de baixa intensidade, houve escassez de sistemas computacionais com essa finalidade, com apenas um estudo.

Objective:To investigate studies that present computational systems to aid healing and systems which refer to the use of low-level laser. Method: Scope review that aimed to answer the question: Which computer systems help in wound healing? A subquestion was: Which of the computer systems refer to the use of low-level laser? Results: From the search, applying the eligibility criteria, 49 articles made up the final sample. The systems served multiple purposes in support of wound healing; the majority presented the health professional as a user of the system; medicine was the most mentioned professional area despite nursing being involved in the management of care for people with wounds. Innovation in care using the computer system was frequently reported, demonstrating the importance of this type of tool for clinical practice. There was a high frequency of the mobile platform, showing that this is a current trend. Conclusion: Computer systems have been used as tools to support patients and especially professionals in wound healing. Regarding the systems aimed at the low intensity laser, there was a shortage of computer systems for this purpose, with a study.

Objetivo:Investigar estudios que presenten sistemas computacionales de ayuda a la cicatrización y sistemas que se refieran al uso de láser de bajo nivel. Método: Revisión de alcance que tuvo como objetivo responder a la pregunta: ¿Qué sistemas informáticos ayudan en la cicatrización de heridas? Una subpregunta fue: ¿Cuál de los sistemas informáticos se refieren al uso de láser de bajo nivel? Resultados: A partir de la búsqueda, aplicando los criterios de elegibilidad, 49 artículos conformaron la muestra final. Los sistemas sirvieron para múltiples propósitos en apoyo de la cicatrización de heridas; la mayoría presentó al profesional de la salud como usuario del sistema; la medicina fue el área profesional más mencionadas, a pesar de que la enfermería está involucrada en la gestión del cuidado de las personas con heridas. La innovación en la atención basada en el uso del sistema informático fue relatada con frecuencia, demostrando la importancia de este tipo de herramienta para la práctica clínica. Hubo una alta frecuencia de la plataforma móvil, lo que demuestra que esta es una tendencia actual. Conclusión: Los sistemas informáticos se han utilizado como herramientas de apoyo a los pacientes y especialmente a los profesionales en la cicatrización de heridas. En cuanto a los sistemas dirigidos al láser de baja intensidad, hubo escasez de sistemas informáticos para este fin, con un estudio.

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O uso da Tecnologia da Informação está presente nos mais diversos domínios, inclusive no da saúde, ao utilizar várias metodologias e ferramentas computacionais. O objetivo deste artigo é apresentar o modelo conceitual baseado em ontologia sobre o domínio HIV/aids denominado OntoHI. No processo para desenvol-ver a OntoHI adotam-se a metodologia SABiO e a ontologia de fundamentação UFO, além do conhecimento de especialistas da área da saúde, o que garante a representação da realidade. Artefatos da ontologia aqui apresentados: representação gráfica, glossário de termos, questões de competência. O controle de qualidade se dá através dos processos de validação e verificação das questões de competências. A OntoHI possibilita a integração com representações de outros domínios. Pode ser utilizado como artefato para a construção de ferramentas computacionais, principalmente sistemas de informações e aplicativos móveis para acompanhar o tratamento de pacientes, além de poder ser expandida para se adaptar a novas situações

The use of Information Technology is present in the most diverse domains, including health care, using various methodologies and computational tools. The goal of this work is to present an ontology-driven con-ceptual model on the HIV/AIDS domain called OntoHI. In the process of developing OntoHI, the SABiO methodology and the UFO foundational ontology are adopted, in addition to the specialist's knowledge in the field of health care, which guarantees a consistent representation of reality. Ontology artifacts that are presented here: graphical representation, glossary of terms, validation of competence questions. Quality control happens in the process of validation and verification of competency questions. OntoHI enables in-tegration with representations from other domains. It can be used as an artifact for building computational tools, mainly information systems and mobile applications to monitor patient treatment, in addition to being able to be expanded to adapt to new situations

El uso de las Tecnologías de la Información ocurre en los más diversos dominios, incluido el de la salud, uti-lizando diversas metodologías y herramientas computacionales. El objetivo de este trabajo es presentar el modelo conceptual basado en ontologías sobre el dominio del VIH/sida denominado OntoHI. En el proceso de desarrollo de OntoHI se adoptan la metodología SABiO y la ontología de fundamentos OVNI, además del conocimiento de especialistas en el campo de la salud, lo que garantiza la representación de la realidad. Artefactos ontológicos presentados: representación gráfica, glosario, temas competenciales. El control de calidad se lleva a cabo a través del proceso de validación y verificación de problemas de competencia. Onto-HI permite la integración con representaciones de otros dominios. Puede usarse como artefacto para cons-truir herramientas computacionales, principalmente sistemas de información y aplicaciones móviles para monitorear el tratamiento del paciente, además de poder expandirse para adaptarse a nuevas situaciones

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La simulación es un recurso ampliamente utilizado en los procesos formativos en odontología, especialmente para adquirir destrezas motrices y potencialmente en el desarrollo de la autoeficacia. Objetivo: Evaluar el efecto de la simulación háptica en la autoeficacia académica de odontólogos en formación. Materiales y métodos: Este estudio se centró en estudiantes de un curso de anticipación disciplinar (n=134). Se aplicó la escala de autoeficacia general después de dos actividades de tallado con apresto tradicional, mediadas por una sesión de tallado con simulación háptica. Resultados: Al determinar el rol de las dimensiones de autoeficacia en dos actividades de simulación tradicional (ABT1 y ABT2), mediadas por la háptica se obtuvo un promedio de ABT1: x̄=3,27 (n=123) y de ABT2: x̄=3,20 (n=105). De los diez ítems de la escala, hubo diferencia estadística respecto a la disminución del grado de autoeficacia en el Nº1 (p=0,05) y Nº6 (p=0,01). Conclusiones: Se puede establecer que, al utilizar un simulador háptico de manera complementaria a las de apresto tradicional, la intervención influye en la autoeficacia, puesto que se adquiere mayor conciencia de las complejidades asociadas, debiendo desafiar su propia autorregulación para hacerles frente.

Simulation is a widely used resource in dental training processes, especially to acquire motor skills and potentially in the development of self-efficacy. Objective: To evaluate the effect of haptic simulation in the academic self-efficacy of dentists in training. Materials and methods: This study focused on students of a curricular anticipatory course (n=134). The general self-efficacy scale was applied after two carving activities with a traditional approach, complemented by a carving session with haptic simulation. Results: When determining the role of the self-efficacy dimensions in two traditional simulation activities (ABT1 and ABT2) complemented by haptics, we obtained an average of ABT1: x̄=3,27 (n=123) and ABT2: x̄=3,20 (n=105). Of the ten items of the scale, there was a statistical difference regarding the decrease in the degree of self-efficacy in Nº1 (p=0,05) and Nº6 (p=0,01). Conclusions: It can be established that complementing traditional training with a haptic simulator influences self-efficacy, since the students become more aware of the associated complexities, and need to challenge their own self-regulation to deal with them.

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INTRODUCTION: Gastric cancer (GC) is the fifth most diagnosed neoplasia and the third leading cause of cancer-related deaths. A substantial number of patients exhibit an advanced GC stage once diagnosed. Therefore, the search for biomarkers contributes to the improvement and development of therapies. OBJECTIVE: This study aimed to identify potential GC biomarkers making use of in silico tools. METHODS: Gastric tissue microarray data available in Gene Expression Omnibus and The Cancer Genome Atlas Program was extracted. We applied statistical tests in the search for differentially expressed genes between tumoral and non-tumoral adjacent tissue samples. The selected genes were submitted to an in-house tool for analyses of functional enrichment, survival rate, histological and molecular classifications, and clinical follow-up data. A decision tree analysis was performed to evaluate the predictive power of the potential biomarkers. RESULTS: In total, 39 differentially expressed genes were found, mostly involved in extracellular structure organization, extracellular matrix organization, and angiogenesis. The genes SLC7A8, LY6E, and SIDT2 showed potential as diagnostic biomarkers considering the differential expression results coupled with the high predictive power of the decision tree models. Moreover, GC samples showed lower SLC7A8 and SIDT2 expression, whereas LY6E was higher. SIDT2 demonstrated a potential prognostic role for the diffuse type of GC, given the higher patient survival rate for lower gene expression. CONCLUSION: Our study outlines novel biomarkers for GC that may have a key role in tumor progression. Nevertheless, complementary in vitro analyses are still needed to further support their potential.

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Los modelos de estudio son un registro fundamental para el diagnóstico, el plan de tratamiento, la presentación de caso y la evaluación del progreso del tratamiento dental; son registros anatomofisiológicos de las arcadas dentarias que sirven para evaluar la dentición en los tres planos del espacio y la oclusión en la relación cúspide-fosa, en una dimensión estática y dinámica. Para obtener los modelos de estudio es imprescindible obtener impresiones totales con diversos materiales de impresión de los arcos dentarios, que reproduzcan fielmente todos los detalles anatómicos, para posteriormente obtener un modelo en yeso piedra. Los modelos obtenidos a partir de una impresión generalmente son a base de yeso odontológico, los cuales a pesar de sus mejoras aún conservan algunas características negativas como: baja resistencia a la fractura por impacto, baja resistencia al desgaste por abrasión, inestabilidad dimensional y radiopacidad que impide la simulación de procedimientos endodóncicos. Con la finalidad de mejorar la simulación en la práctica odontológica, se usa la resina epóxica que puede emplearse en la obtención de modelos, este material es más resistente y presenta una mayor resistencia a la abrasión; además es radiolúcido, por lo que es útil para la réplica de preparaciones y procedimientos de simulación endodóntica. Los detalles de la superficie obtenidos con resina epóxica son superiores a los obtenidos con yeso. El uso de simuladores es una herramienta educativa con la que se favorece la adquisición de ciertas habilidades, destrezas, técnicas y competencias necesarias para la formación de estudiantes o profesionales de odontología. En el presente trabajo se describe la técnica para la elaboración de modelos dentales didácticos en resina epóxica para utilizarlos en la enseñanza de la práctica odontológica (AU)

Study studies are a fundamental record for diagnosis, treatment plan, case presentation and evaluation of the progress of dental treatment. They are anatomo-physiological records of the dental arches to evaluate the dentition in the three planes of space and the occlusion in the cusp-fossa relationships, in a static and dynamic dimension. To obtain the study models, it is essential to obtain total impressions with various impression materials of the dental arches, which faithfully reproduce all the anatomical details, in order to later obtain a stone plaster model. Those obtained from an impression are generally based on dental plaster, which despite its improvements still retain some negative characteristics such as: low resistance to fracture by impact, low resistance to wear by abrasion, dimensional instability and radio opacity that prevents the simulation of endodontic procedures. In order to improve simulation in dental practice, the use of epoxy resin can be used to obtain models, this material is more resistant and has greater resistance to abrasion, it is radiolucent, which makes them Useful for replicating preparations and endodontic simulation procedures, the surface details obtained with epoxy resin are superior to those obtained with plaster. The use of simulators is an educational tool that favors the acquisition of certain abilities, skills, techniques and competencies necessary for the training of the student or professional in dentistry. In the present work, the technique for the elaboration of didactic dental models in epoxy resin to be used in the teaching of dental practice is described.(AU)

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OBJECTIVE@#Current mainstream PET scattering correction methods are introduced and evaluated horizontally, and finally, the existing problems and development direction of scattering correction are discussed.@*METHODS@#Based on NeuWise Pro PET/CT products of Neusoft Medical System Co. Ltd. , the simulation experiment is carried out to evaluate the influence of radionuclide distribution out of FOV (field of view) on the scattering estimation accuracy of each method.@*RESULTS@#The scattering events produced by radionuclide out of FOV have an obvious impact on the spatial distribution of scattering, which should be considered in the model. The scattering estimation accuracy of Monte Carlo method is higher than single scatter simulation (SSS).@*CONCLUSIONS@#Clinically, if the activity of the adjacent parts out of the FOV is high, such as brain, liver, kidney and bladder, it is likely to lead to the deviation of scattering estimation. Considering the Monte Carlo scattering estimation of the distribution of radionuclide out of FOV, it's helpful to improve the accuracy of scattering distribution estimation.

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OBJECTIVE@#To propose a framework that combines sinogram interpolation with unsupervised image-to-image translation (UNIT) network to correct metal artifacts in CT images.@*METHODS@#The initially corrected CT image and the prior image without artifacts, which were considered as different elements in two different domains, were input into the image transformation network to obtain the corrected image. Verification experiments were carried out to assess the effectiveness of the proposed method using the simulation data, and PSNR and SSIM were calculated for quantitative evaluation of the performance of the method.@*RESULTS@#The experiment using the simulation data showed that the proposed method achieved better results for improving image quality as compared with other methods, and the corrected images preserved more details and structures. Compared with ADN algorithm, the proposed algorithm improved the PSNR and SSIM by 2.4449 and 0.0023 when the metal was small, by 5.9942 and 8.8388 for images with large metals, and by 8.8388 and 0.0130 when both small and large metals were present, respectively.@*CONCLUSION@#The proposed method for metal artifact correction can effectively remove metal artifacts, improve image quality, and preserve more details and structures on CT images.

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Objective: based on summarizing the simulation and prediction of tobacco control measures across the globe and sorting out the various scenarios of tobacco control measures, the potential short-term effects of seven tobacco control measures in different scenarios were systematically analyzed. Methods: Until April 2022, PubMed, Embase, EconLit, PsychINFO, and CINAHL databases were used to retrieve literature about tobacco control measures simulation and prediction models across the globe. Inclusion and exclusion criteria were strictly followed. Meta-analysis for the potential short-term effects of seven tobacco control measures in different scenarios was performed using the R software. Results: A total of 22 papers covering 16 countries were selected. Five studies were conducted in the United States, three in Mexico, and two in Italy. There were all papers with the measures to tax increases, smoke-free air laws, and mass media campaigns, 21 papers with youth access restrictions, 20 with marketing restrictions, and 19 with cessation treatment programs and health warnings. The tax increases had diverse influences on the price elasticity of different age groups. The price elasticity in the age group 15-17 years was the highest, which was 0.044 (95%CI: 0.038-0.051). The potential short-term effects of smoke-free air laws in workplaces were higher than in restaurants and other indoor public places. The effects of youth access restrictions were greater in the age group <16 years than in the age group 16-17. The stronger the implementation of other measures, the greater the potential short-term effects. A comparison of seven tobacco control measures showed that the cessation treatment programs increase in cessation rate was the highest, 0.404 (95%CI: 0.357-0.456). The reduction in smoking rate and reduction in initiation rate of youth access restrictions strongly enforced and publicized was the highest in the age group <16 years, 0.292 (95%CI: 0.269-0.315), and 0.292 (95%CI: 0.270-0.316). Conclusions: The potential short-term effects of seven tobacco control measures in different scenarios were evaluated more accurately and objectively through Meta-analysis. In the short term, cessation treatment programs will substantially increase smoking cessation rates, and strong youth access enforcement will sharply reduce smoking and initiation rates among adolescents under 16. These results also offer strong data-related support for the simulation and prediction of tobacco control measures in China and other countries.

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OBJECTIVE@#To investigate whether Suxiao Jiuxin Pills (SJP), a Chinese herbal remedy, is an anti-ventricular fibrillation (VF) agent.@*METHODS@#VF was induced by isoproterenolol (ISO) intraperitoneal injection followed by electrical pacing in mice and rabbits. The effects of SJP on the L-type calcium channel current (CaV1.2), voltage-dependent sodium channel current (INa), rapid and slow delayed rectifier potassium channel current (IKr and IKs, respectively) were studied by whole-cell patch-clamp method. Computer simulation was implemented to incorporate the experimental data of SJP effects on the CaV1.2 current into the action potential (AP) and pseudo-electrocardiography (pseudo-ECG) models.@*RESULTS@#SJP prevented VF induction and reduced VF durations significantly in mice and rabbits. Patch-clamp experiments revealed that SJP decreased the peak amplitude of the CaV1.2 current with a half maximal concentration (IC50) value of 16.9 mg/L (SJP-30 mg/L, -32.8 ± 6.1 pA; Verapamil, -16.2 ±1.8 pA; vs. control, -234.5 ±16.7 pA, P<0.01, respectively). The steady-state activation curve, inactivation curve, and the recovery from inactivation of the CaV1.2 current were not shifted significantly. Specifically, SJP did not altered INa, IKr, and IKs currents significantly (SJP vs. control, P>0.05). Computer simulation showed that SJP-reduced CaV1.2 current shortened the AP duration, transiting VF into sinus rhythm in pseudo-ECG.@*CONCLUSION@#SJP reduced VF via inhibiting the CaV1.2 current with in vivo, in vitro, and in silico studies, which provide experimental basis for SJP anti-VF clinical application.

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OBJECTIVE@#To compare the predictive ability of two extended Cox models in nonlinear survival data analysis.@*METHODS@#Through Monte Carlo simulation and empirical study and with the conventional Cox Proportional Hazards model and Random Survival Forests as the reference models, we compared restricted cubic spline Cox model (Cox_RCS) and DeepSurv neural network Cox model (Cox_DNN) for their prediction ability in nonlinear survival data analysis. Concordance index was used to evaluate the differentiation of the prediction results (a larger concordance index indicates a better prediction ability of the model). Integrated Brier Score was used to evaluate the calibration degree of the prediction (a smaller index indicates a better prediction ability).@*RESULTS@#For data that met requirement of the proportion risk, the Cox_RCS model had the best prediction ability regardless of the sample size or deletion rate. For data that failed to meet the proportion risk, the prediction ability of Cox_DNN was optimal for a large sample size (≥500) with a low deletion (< 40%); the prediction ability of Cox_RCS was superior to those of other models in all other scenarios. For example data, the Cox_RCS model showed the best performance.@*CONCLUSION@#In analysis of nonlinear low maintenance data, Cox_RCS and Cox_DNN have their respective advantages and disadvantages in prediction. The conventional survival analysis methods are not inferior to machine learning or deep learning methods under certain conditions.

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OBJECTIVE@#To compare different methods for calculating sample size based on confidence interval estimation for a single proportion with different event incidences and precisions.@*METHODS@#We compared 7 methods, namely Wald, AgrestiCoull add z2, Agresti-Coull add 4, Wilson Score, Clopper-Pearson, Mid-p, and Jefferys, for confidence interval estimation for a single proportion. The sample size was calculated using the search method with different parameter settings (proportion of specified events and half width of the confidence interval [ω=0.05, 0.1]). With Monte Carlo simulation, the estimated sample size was used to simulate and compare the width of the confidence interval, the coverage of the confidence interval and the ratio of the noncoverage probability.@*RESULTS@#For a high accuracy requirement (ω =0.05), the Mid-p method and Clopper Pearson method performed better when the incidence of events was low (P < 0.15). In other settings, the performance of the 7 methods did not differ significantly except for a poor symmetry of the Wald method. In the setting of ω=0.1 with a very low p (0.01-0.05), failure of iteration occurred with nearly all the methods except for the Clopper-Pearson method.@*CONCLUSION@#Different sample size determination methods based on confidence interval estimation should be selected for single proportions with different parameter settings.

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Existing neuroregulatory techniques can achieve precise stimulation of the whole brain or cortex, but high-focus deep brain stimulation has been a technical bottleneck in this field. In this paper, based on the theory of negative permeability emerged in recent years, a simulation model of magnetic replicator is established to study the distribution of the induced electric field in the deep brain and explore the possibility of deep focusing, which is compared with the traditional magnetic stimulation method. Simulation results show that a single magnetic replicator realized remote magnetic source. Under the condition of the same position and compared with the traditional method of stimulating, the former generated smaller induced electric field which sharply reduced with distance. By superposition of the magnetic field replicator, the induced electric field intensity could be increased and the focus could be improved, reducing the number of peripheral wires while guaranteeing good focus. The magnetic replicator model established in this paper provides a new idea for precise deep brain stimulation, which can be combined with neuroregulatory techniques in the future to lay a foundation for clinical application.

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In order to improve the wearing comfort and bearing effectiveness of the exoskeleton, based on the prototype and working mechanism analysis of a relaxation wearable system for knee exoskeleton robot, the static optimization synthesis and its method are studied. Firstly, based on the construction of the virtual prototype model of the system, a comprehensive wearable comfort evaluation index considering the factors such as stress, deformation and the proportion of stress nodes was constructed. Secondly, based on the static simulation and evaluation index of system virtual prototype, multi-objective genetic optimization and local optimization synthesis of armor layer topology were carried out. Finally, the model reconstruction simulation data confirmed that the system had good wearing comfort. Our study provides a theoretical basis for the bearing performance and prototype construction of the subsequent wearable system.

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For the detection and identification of abnormal nodular tissues on the body surface, a microwave sensor structure loaded with a spiral resonator is proposed in this paper, a sensor simulation model is established using HFSS software, the structural parameters are optimized, and the actual sensor is fabricated. The S21 parameters of the tissue were obtained when nodules appeared by simulation, and the characteristic relationship between the difference of S21 parameters with position was analyzed and tested experimentally. The results showed that when nodules were present in normal tissues, the curve of S21 parameter difference with position change had obvious inverted bimodal characteristics, and the extreme value of S21 parameter difference appeared when the sensor was directly above the nodules, which was easy to identify the position of nodules. It provides an objective detection tool for the identification of abnormal nodular tissues on the body surface.

ABSTRACT

OBJECTIVES@#To compare the application value of the likelihood ratio (LR) method and identity by state (IBS) method in the identification involving half sibling relationships, and to provide a reference for the setting of relevant standards for identification of half sibling relationship.@*METHODS@#(1) Based on the same genetic marker combinations, the reliability of computer simulation method was verified by comparing the distributions of cumulated identity by state score (CIBS) and combined full sibling index in actual cases with the distributions in simulated cases. (2) In different numbers of three genetic marker combinations, the simulation of full sibling, half sibling and unrelated individual pairs, each 1 million pairs, was obtained; the CIBS, as well as the corresponding types of cumulative LR parameters, were calculated. (3) The application value of LR method was compared with that of IBS method, by comparing the best system efficiency provided by LR method and IBS method when genetic markers in different amounts and of different types and accuracy were applied to distinguish the above three relational individual pairs. (4) According to the existing simulation data, the minimum number of genetic markers required to distinguish half siblings from the other two relationships using different types of genetic markers was estimated by curve fitting.@*RESULTS@#(1) After the rank sum test, under the premise that the real relationship and the genetic marker combination tested were the same, there was no significant difference between the simulation method and the results obtained in the actual case. (2) In most cases, under the same conditions, the system effectiveness obtained by LR method was greater than that by IBS method. (3) According to the existing data, the number of genetic markers required for full-half siblings and half sibling identification could be obtained by curve fitting when the system effectiveness reached 0.95 or 0.99.@*CONCLUSIONS@#When distinguishing half sibling from full sibling pairs or unrelated pairs, it is recommended to give preference to the LR method, and estimate the required number of markers according to the identification types and the population data, to ensure the identification effect.

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In the context of Pharma 4.0, the design tools that support the pharmaceutical Quality by Design(QbD) are iterating fast toward intelligent or smart design. The conventional development methods for traditional Chinese medicine(TCM) preparations have the limitations such as over dependence on experience, low dimensions for the designed experiment parameters, poor compatibility between the process and equipment, and high trial-and-error cost during process scale-up. Therefore, this paper innovatively proposed the intelligent co-design involving material, process, and equipment for manufacturing high-quality TCM preparations, and introduced the design philosophy, targets, tools, and applications with TCM oral solid dosage(OSD) as an example. In terms of design philosophy, the pharmaceutical design tetrahedron composed of critical material attributes, critical process parameters, critical equipment attributes, and critical quality attributes was developed. The design targets were put forward based on the product performance classification system. The design tools involve a design platform that contains several modules, such a as the iTCM material database, the processing route classification system, the system modeling and simulation, and reliability-based optimization. The roles of different modules in obtaining essential and universal design knowledge of the key common manufacturing units were introduced. At last, the applications of the co-design methodology involving material, process, and equipment in the high shear wet granulation process development and the improvement of the dissolving or dispersion capability of TCM formula granules are illustrated. The research on advanced pharmaceutical design theory and methodology will help enhance the efficiency and reliability of drug development, improve the product quality, and promote the innovation of high-end TCM products across the industry.

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At present, most of the research on hip exoskeleton robots adopts the method of decoupling analysis of hip joint motion, decoupling the ball pair motion of hip joint into rotational motion on sagittal plane, coronal plane and cross section, and designing it into series mechanism. Aiming at the problems of error accumulation and man-machine coupling in series mechanism, a parallel hip rehabilitation exoskeleton structure is proposed based on the bionic analysis of human hip joint. The structure model is established and the kinematics analysis is carried out. Through the OpenSim software, the curve of hip flexion and extension, adduction and abduction angle in a gait cycle is obtained. The inverse solution of the structure is obtained by the D-H coordinate system method. The gait data points are selected and compared with the inverse solution obtained by ADAMS software simulation. The results show that the inverse solution expression is correct. The parallel hip exoskeleton structure can meet the requirements of the rotation angle of the hip joint of the human body, and can basically achieve the movement of the hip joint, which is helpful to improve the human-computer interaction performance of the exoskeleton.

ABSTRACT

Ventilator is an important medical instrument which can replace the function of autonomous ventilation artificially. Its safety and reliability are related to the health and even life safety of patients. With the publishing of the new national standard and international standard for ventilators, higher requirements are put forward for the detection and evaluation. This study mainly introduces an automatic test system for ventilator performance. The test system is based on PF-300 air-flow analyzer of Imtmedical and standard simulation lung. The automatic switch module of simulation lung is developed, and the automatic test system of ventilator is designed using the software development platform based on Python. It can not only automatically test all ventilation control parameters and monitoring parameters of the ventilator, but also realize automatic data recording, form reports and data analysis, and improve the efficiency and quality of inspection, detection and quality control.