topr: an R package for viewing and annotating genetic association results.

BACKGROUND: The successful identification of genetic loci for complex traits in genome-wide association studies (GWAS) has resulted in thousands of GWAS summary statistics becoming publicly available for hundreds of complex traits from multiple cohorts and studies. Visualisation is an important aid for interpreting, comparing, validating, and obtaining an overview of large amounts of data. However, the current software is limited in its ability and flexibility to annotate and simultaneously display multiple GWAS results which is useful when interpreting and comparing association results. Therefore, I created the topr R package to facilitate visualisation, annotation, and comparisons of single or multiple GWAS results. It contains functions tailored for viewing and analysing GWAS results. RESULTS: topr provides a fast and elegant visual display of association results, along with the annotation of association peaks with their nearest gene. Association results from multiple analyses can be viewed simultaneously over the entire genome or in a more detailed regional view along with gene information. Users can perform the essential steps of visually exploring and annotating association results and generating elegant publication-ready plots. CONCLUSIONS: topr is developed as a package for the R statistical computing environment, released under the GNU General Public License, and is freely available on the Comprehensive R Archive Network ( http://cran.r-project.org/package=topr ). The source code is available at GitHub ( https://github.com/totajuliusd/topr ). topr provides several advantages and advances over the current alternatives, particularly in its gene annotation functionality and customisable display of single- or multiple-association results. With topr, I provide a flexible tool with multiple features to aid in the analysis and evaluation of GWAS association results.

Aplicación móvil para el análisis estadístico en Android / Mobile application for statistics analysis on Android

El uso de dispositivos móviles en la vida moderna es imprescindible debido a las ventajas que brindan al ofrecer nuevas posibilidades e implementar de manera virtual servicios ya establecidos. La mayor existencia de móviles que computadoras en los estudiantes de Cuba nos motivó a la realización de esta aplicación. El objetivo de este artículo es describir la aplicación nombrada Cálculos estadísticos y tasas en salud (Calc. Tasas versión 1.7) construida para realizar cálculos en un curso de Bioestadística, cubriendo gran parte del contenido de esta asignatura en la enseñanza de pregrado de las universidades médicas, así como otros contenidos de interés en esta materia. También incorpora una base de datos con información demográfica y sanitaria de Cuba y sus provincias en el período 2013-2020. Como resultado se logró independencia tecnológica al dejar de usar programas foráneos y se logró una mayor portabilidad pues funciona tanto en móviles como en computadoras utilizando un emulador de Android(AU)

The use of mobile devices in modern life is essential due to the advantages they provide, offering new possibilities and implementing virtual services. The existence of greater number of mobiles phones than computers in Cuban students motivated the realization of this application. The objective of the article is to describe the application Statistical calculations and rates in health (Calc. Rates version 1.7) built to perform calculations in a Biostatistics course, covering a large part of the content of this subject in the undergraduate teaching of medical universities, as well as other content related with this topic. It also incorporates a database with demographic and health information on Cuba and its provinces in the period 2013-2020. As a result, technological independence was achieved by stopping using foreign programs and a greater portability, since it works on both mobile phones and computers through an Android emulator(AU)

Application of Edge Computing in Structural Health Monitoring of Simply Supported PCI Girder Bridges.

This study proposes an innovative method for structural health monitoring of simply supported PCI girder bridges based on dynamic strain and edge computing. Field static and dynamic load tests were conducted on a bridge consisting of a span with newly replaced PCI girders and numerous spans with old PCI girders. Both the static and dynamic test results showed that the flexural rigidity of the old PCI girders decreased significantly due to deterioration. To improve the efficiency of on-site monitoring data transmission and data analysis, this study developed a smart dynamic strain gauge node with the function of edge computing. Continuous data with a sampling frequency of 100 Hz were computed at the sensor node. Among the computed results, only the maximum dynamic strain data caused by the passage of the heaviest vehicle within 1 min were transmitted. The on-site monitoring results indicated that under routine traffic conditions, the dynamic strain response of the new PCI girder was smaller than that of the deteriorated PCI girder. When the monitored dynamic strain response has a tendency to magnify, attention should be paid to the potential prestress loss or other deterioration behaviors of the bridge.

Continuum of care for maternal health in Uganda: A national cross-sectional study.

INTRODUCTION: A continuum of maternal care approach can reduce gaps and missed opportunities experienced by women and newborns. We determined the level of coverage and factors associated with the continuum of maternal care in Uganda. METHODS: We used weighted data from the Uganda Demographic and Health Survey (UDHS) 2016. We included 10,152 women aged 15 to 49 years, who had had a live birth within five years preceding the survey. Stratified two-stage cluster sampling design was used to select participants. Continuum of maternal care was considered when a woman had at least four antenatal care (ANC) visits, had delivered in a health facility and they had at least one postnatal check-up within six weeks. We conducted multivariable logistic regression analysis to determine factors associated with completion of the continuum of maternal care using SPSS version 25. RESULTS: The level of coverage of complete continuum of maternal care was 10.7% (1,091) (95% CI: 10.0-11.2). About 59.9% (6,080) (95% CI: 59.0-60.8) had four or more antenatal visits while 76.6% (7,780) (95% CI: 75.8-77.5) delivered in a health facility and 22.5% (2,280) (95% CI: 21.5-23.2) attended at least one postnatal care visit within six weeks. The following factors were associated with continuum of maternal care; initiating ANC in the first trimester (AOR 1.49, 95% CI: 1.23-1.79), having secondary level of education (AOR 1.60, 95% CI: 1.15-2.22) and tertiary level of education (AOR 2.08 95% CI: 1.38-3.13) compared to no formal education, being resident in Central Uganda (AOR 1.44, 95% CI:1.11-1.89), Northern Uganda (AOR 1.35, 95% CI: 1.06-1.71) and Western Uganda (AOR 0.61, 95% CI: 0.45-0.82) compared to Eastern Uganda, and exposure to newspapers and magazines. CONCLUSION: The level of coverage of the complete continuum of maternal care was low and varied across regions. It was associated with easily modifiable factors such as early initiation of ANC, exposure to mass media and level of education. Interventions to improve utilisation of the continuum of maternal care should leverage mass media to promote services, especially among the least educated and the residents of Western Uganda.

PSS Health: como calcular tamanho de amostra para testar relações de variáveis com um desfecho binário / PSS Health: how to calculate the sample size to test variables relationships with a binary outcome

Dando continuidade à série de artigos que pretendem orientar o usuário na utilização da ferramenta PSS Health para o planejamento de uma pesquisa, esta edição apresenta um passo a passo de como realizar o cálculo para tamanho de amostra e de quais informações são necessárias para testar relações estatísticas entre variáveis e um desfecho binário: comparação de proporções entre grupos independentes (dois ou mais), comparação de duas proporções dependentes e regressão logística. Todos os exemplos também são ilustrados e disponibilizados em vídeos no canal da Unidade de Bioestatística.

Following the series of articles that aim to guide the user in using the PSS Health tool for planning research, this issue presents a step-by-step guide on how to perform the sample size calculation and what information is needed to test statistical relationships between variables and a binary outcome: comparison of proportions between independent groups (two or more), comparison of two dependent proportions, and logistic regression. All examples are also illustrated and available in videos on the Biostatistics Unit's channel.

A double-blinded randomized clinical trial of pain perception during orthodontic treatment / Ensaio clínico randomizado duplo cego de percepção da dor durante tratamento ortodôntico

Introduction: Orthodontic movement can cause painful symptoms, especially in the early stages of treatment. Objective: This study aimed to compare the performance of chewing gum and ibuprofen in pain control during the initial period of orthodontic treatment. Material and method: A randomized blind clinical trial, with an allocation ratio of 1:1, was developed with patients aged ≥18 years old. The sample size was established considering a significance level of 5% and test power of 80%, resulting in a minimum of 30 volunteers per group (n=90). Participants were paired regarding sex, age, the severity of malocclusion, defined by the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN), and crowding, determined by Little's irregularity index. The sample was randomly allocated to three groups: Group I (control) placebo; Group II chewing gum; and Group III Ibuprofen. Pain perception was evaluated by the Visual Analog Scale (VAS) in the first 24, 36, and 48 hours after activation of the orthodontic appliance. The data were analyzed by generalized linear models for repeated measures in time. Result: No statistically significant difference (p>0.05) was observed among the groups for the methods of pain therapy evaluated in 24, 36, and 48 hours post-activation. Conclusion: There was no difference among the method used for pain control during the orthodontic treatment.

Introdução: A movimentação ortodôntica pode causar sintomatologia dolorosa, principalmente nas fases iniciais do tratamento. Objetivo: Este estudo teve como objetivo comparar o desempenho da goma de mascar e do ibuprofeno no controle da dor durante o período inicial do tratamento ortodôntico. Material e método: Foi desenvolvido um ensaio clínico randomizado cego, com razão de alocação de 1:1, com pacientes com idade ≥ 18 anos. O tamanho da amostra foi estabelecido considerando um nível de significância de 5% e poder do teste de 80%, resultando em um mínimo de 30 voluntários por grupo (n=90). Os participantes foram pareados quanto ao sexo, idade, gravidade da má oclusão, definida pelo Componente de Saúde Bucal (DHC) do Índice de Necessidade de Tratamento Ortodôntico (IOTN), e apinhamento, determinado pelo índice de irregularidade de Little. A amostra foi distribuída aleatoriamente em três grupos: Grupo I (controle) placebo; Goma de mascar Grupo II; e Grupo III Ibuprofeno. A percepção da dor foi avaliada pela Escala Visual Analógica (EVA) nas primeiras 24, 36 e 48 horas após a ativação do aparelho ortodôntico. Os dados foram analisados por modelos lineares generalizados para medidas repetidas no tempo. Resultado Não foi observada diferença estatisticamente significativa (p>0.05) entre os grupos para os métodos de terapia da dor avaliados em 24, 36 e 48 horas pós-ativação. Conclusão: Não houve diferença entre o método utilizado para controle da dor durante o tratamento ortodôntico.

Glass ionomer heated or not to identify bone defect created in rat calvaria / Ionômero de vidro aquecido ou não para identificação de defeitos ósseos criados em calvárias de ratos

Introduction: Some experimental models have been used to evaluate the use of biomaterials in bone regeneration. Among them are the critical size defects (CSD) created in rat calvaria. An experimental model has been described in the literature, in which "L" markings are performed on the margins of the bone defects in order to assist in the precise identification of these defects during laboratory processing and analysis of the results. In the proposed model, the "L" markings are filled with amalgam. Objective: The purpose of the present study was to evaluate the amalgam replacement of an experimental bony defect model in rat calvaria by heated or unheated glass ionomer. Material and method: 24 rats were used. A 5 mm CSD was created at each animal calvaria. Two "L" shaped markings were made 2 mm from the margins of the bone defect, filled with amalgam (Group AM), heated glass ionomer cement (Group GIh) or not (Group GI). The animals were euthanized 15 days postoperatively. The areas of the surgical defect and the L-shaped marking were histomorphometrically analyzed and the data were analyzed statistically (p <0.05). Result: There were no significant clinical, histological or methodological differences among the experimental groups. Conclusion: It can be concluded that GI can replace AM in the proposed experimental model and GI heating did not promote additional benefits.

Introdução: Alguns modelos experimentais têm sido usados para avaliar o uso de biomateriais na regeneração óssea. Entre eles estão os defeitos de tamanho crítico (DTC) criados em calvárias de ratos. Um modelo experimental foi descrito na literatura onde marcações em L são realizadas nas margens do defeito ósseo para auxiliar na identificação precisa desses defeitos durante o processamento laboratorial e análise dos resultados. No modelo experimental proposto, as marcações em "L" são preenchidas com amálgama. Objetivo: Avaliar a substituição do amálgama por ionômero de vidro aquecido ou não em um modelo experimental para identificação de defeito ósseo criado em calvária de ratos. Material e método: Foram utilizados 24 ratos. Um DTC de 5 mm de diâmetro foi criado na calvária de cada animal. Duas marcações em "L" foram realizadas a 2 mm das margens do defeito ósseo, preenchidas com amálgama (Grupo AM), ionômero de vidro aquecido (Grupo CIVaq) ou não (Grupo CIV). Os animais foram eutanasiados aos 15 dias pós-operatórios. A área do defeito cirúrgico e das marcações em "L" foram histomorfometricamente avaliadas e os dados estatisticamente analisados (p<0,05). Resultado: Não houve diferença estatisticamente significativa entre os grupos experimentais para as análises metodológicas, clínicas ou histomorfométrica realizadas. Conclusão: Dentro dos limites deste estudo, pode-se concluir que CIV pode substituir o AM no modelo experimental proposto e o aquecimento do CIV não promoveu benefícios adicionais.

Association between periodontitis and type 2 diabetes mellitus: study in a population attended by the Brazilian Health System / Associação entre periodontite e diabetes mellitus tipo 2: estudo em uma população atendida pelo Sistema Único de Saúde Brasileiro

Introduction: Periodontitis control helps to prevent and control diabetes mellitus and understanding of this relationship can lead to changes in health policy. Objective: The purpose of this study was to investigate the association between periodontitis, knowledge, and glycemic control. Material and method: This is a cross-sectional analytical epidemiological survey with 216 Type 2 diabetic patients, non-smokers, who had current blood screenings with glycated hemoglobin (HbA1c). Result: Overall, 93.51% of the patients reported brushing their teeth at least twice a day, 62.5% visited the dentist last year, 81.58% have already undergone treatment for periodontal disease, 43.52% reported having periodontitis and 59.72% had controlled diabetes. No significant (p=0.603) association between HbA1c control and the presence of periodontitis was found. Among the patients with periodontitis, no association between HbA1c control and information on the periodontal disease was found (p=0.996), and know/believe in its relationship with diabetes (p=0.659; p=0.973). Conclusion: No relationship between periodontitis and diabetes was found in the sample, as well as in patients with periodontitis, those with knowledge on periodontal disease and knowledge/belief in its relationship with diabetes, which could be justified by the care by a multi-professional health team.

Introdução: O controle da doença periodontal auxilia na prevenção e no controle do diabetes mellitus. A compreensão dessa relação pode desencadear mudanças nas políticas públicas de saúde. Objetivo: O objetivo deste estudo foi investigar a associação entre a doença periodontal, o controle glicêmico e o conhecimento dessa relação. Material e método: Trata-se de um inquérito epidemiológico analítico transversal com 216 pacientes com diabetes mellitus tipo 2, não fumantes, que realizaram exames de sangue atuais com hemoglobina glicada (HbA1c). Resultado: No geral, 93,51% dos pacientes relataram escovar os dentes pelo menos duas vezes ao dia, 62,5% visitaram o dentista no último ano, 81,58% já fizeram tratamento para doença periodontal, 43,52% relataram ter periodontite e 59,72% tinham diabetes controlado. Não foi encontrada associação significativa (p=0,603) entre o controle da HbA1c e a presença de periodontite. Entre os pacientes com periodontite, não foi encontrada associação entre o controle da HbA1c e informações sobre a doença periodontal (p=0,996), e conhecer/acreditar na sua relação com o diabetes (p=0,659; p=0,973). Conclusão: Não foi encontrada relação entre a doença periodontal e diabetes na amostra, o que poderia ser justificado pelo atendimento por uma equipe multiprofissional de saúde no Sistema Único de Saúde Brasileiro.

Oscillatory electroencephalographic patterns of arithmetic problem solving in fourth graders.

Numerous studies have identified neurophysiological correlates of performing arithmetic in adults. For example, oscillatory electroencephalographic (EEG) patterns associated with retrieval and procedural strategies are well established. Whereas fact retrieval has been linked to enhanced left-hemispheric theta ERS (event-related synchronization), procedural strategies are accompanied by increased bilateral alpha ERD (event-related desynchronization). It is currently not clear if these findings generalize to children. Our study is the first to investigate oscillatory EEG activity related to strategy use and arithmetic operations in children. We assessed ERD/ERS correlates of 31 children in fourth grade (aged between nine and ten years) during arithmetic problem solving. We presented multiplication and subtraction problems, which children solved with fact retrieval or a procedure. We analyzed these four problem categories (retrieved multiplications, retrieved subtractions, procedural multiplications, and procedural subtractions) in our study. In summary, we found similar strategy-related patterns to those reported in previous studies with adults. That is, retrieval problems elicited stronger left-hemispheric theta ERS and weaker alpha ERD as compared to procedural problems. Interestingly, we observed neurophysiological differences between multiplications and subtractions within retrieval problems. Although there were no response time or accuracy differences, retrieved multiplications were accompanied by larger theta ERS than retrieved subtractions. This finding could indicate that retrieval of multiplication and subtraction facts are distinct processes, and/or that multiplications are more frequently retrieved than subtractions in this age group.

Best practices in statistical computing.

The world is becoming increasingly complex, both in terms of the rich sources of data we have access to and the statistical and computational methods we can use on data. These factors create an ever-increasing risk for errors in code and the sensitivity of findings to data preparation and the execution of complex statistical and computing methods. The consequences of coding and data mistakes can be substantial. In this paper, we describe the key steps for implementing a code quality assurance (QA) process that researchers can follow to improve their coding practices throughout a project to assure the quality of the final data, code, analyses, and results. These steps include: (i) adherence to principles for code writing and style that follow best practices; (ii) clear written documentation that describes code, workflow, and key analytic decisions; (iii) careful version control; (iv) good data management; and (v) regular testing and review. Following these steps will greatly improve the ability of a study to assure results are accurate and reproducible. The responsibility for code QA falls not only on individual researchers but institutions, journals, and funding agencies as well.

Modelo matemático para predecir la formación de agregados en el proceso de purificación de un anticuerpo monoclonal / Mathematical model for predicting the formation of aggregates in the purification process of a monoclonal antibody

El uso de anticuerpos monoclonales en la lucha contra el cáncer se convierte cada día más en la terapia de elección. Para la introducción de anticuerpos monoclonales en mercados internacionales de alta demanda y con elevados requerimientos de calidad se requiere su producción a gran escala. El incremento de la presencia de dímeros en el producto final afecta su calidad y, por tanto, la eficiencia y eficacia del proceso. El objetivo del presente trabajo fue obtener un modelo matemático que permita relacionar el porcentaje de dímeros con las variables de operación de mayor influencia. Se realizó el ajuste de un modelo de regresión lineal múltiple usando el programa Statgraphics Centurion XVII versión 17.2.00. El modelo se validó con lotes de producción, logrando errores relativos inferiores al 20 por ciento. Las variables significativas obtenidas fueron: masa de IgG en el sobrenadante; masa de IgG en el producto de salida del paso de captura de proteína A; pH en el producto de salida del paso de captura de proteína A; pH del producto ajustado y conductividad de salida en la membrana de intercambio aniónico. El modelo permitió encontrar un intervalo de trabajo de las variables de mayor influencia en la formación de dímeros para reducirlos hasta valores inferiores al 3 por ciento(AU)

The use of monoclonal antibodies in the fight against cancer is becoming more and more the selected therapy. The introduction of monoclonal antibodies highly demanded in international markets, with high quality requirements needs the production of monoclonal antibodies on a large scale. The increase of dimers in the final product affects its quality, therefore, the efficiency and effectiveness of the process. The objective of this work was to obtain a mathematical model to relate the percentage of dimers with the most influential operating variables. A multiple linear regression model was obtained using Statgraphics Centurion XVII version 17.2.00 software. The model was validated with new production data with a mean error of validation below 20 percent. The significant variables were: supernatant IgG mass; IgG mass in the effluent from Protein A capture column; pH of the effluent from Protein A capture column; pH of the adjusted product and conductivity of the effluent from anionic exchange membrane. A working interval for each of the influential variables were established, in order to reduce dimers below 3 percent(AU)

Predicting partition coefficients for the SAMPL7 physical property challenge using the ClassicalGSG method.

The prediction of [Formula: see text] values is one part of the statistical assessment of the modeling of proteins and ligands (SAMPL) blind challenges. Here, we use a molecular graph representation method called Geometric Scattering for Graphs (GSG) to transform atomic attributes to molecular features. The atomic attributes used here are parameters from classical molecular force fields including partial charges and Lennard-Jones interaction parameters. The molecular features from GSG are used as inputs to neural networks that are trained using a "master" dataset comprised of over 41,000 unique [Formula: see text] values. The specific molecular targets in the SAMPL7 [Formula: see text] prediction challenge were unique in that they all contained a sulfonyl moeity. This motivated a set of ClassicalGSG submissions where predictors were trained on different subsets of the master dataset that are filtered according to chemical types and/or the presence of the sulfonyl moeity. We find that our ranked prediction obtained 5th place with an RMSE of 0.77 [Formula: see text] units and an MAE of 0.62, while one of our non-ranked predictions achieved first place among all submissions with an RMSE of 0.55 and an MAE of 0.44. After the conclusion of the challenge we also examined the performance of open-source force field parameters that allow for an end-to-end [Formula: see text] predictor model: General AMBER Force Field (GAFF), Universal Force Field (UFF), Merck Molecular Force Field 94 (MMFF94) and Ghemical. We find that ClassicalGSG models trained with atomic attributes from MMFF94 can yield more accurate predictions compared to those trained with CGenFF atomic attributes.

BA-plotteR - A web tool for generating Bland-Altman plots and constructing limits of agreement.

Investigators use Bland-Altman plot (Limits of Agreement plot) to compare two methods measuring the same continuous variable to determine interchangeability or agreement of the methods. The method has evolved to deal with heteroscedastic data and fixed or proportional biases (or both). Although an ordinary Bland-Altman plot can be readily made with various software applications, there is no free, open-source application that is dedicated to producing Bland-Altman plots and constructing limits of agreement for data that do not meet the assumptions of a simple comparison. To fill this gap, we created BA-plotteR, a web-based, open-source, freeware tool created in Shiny/R that is dedicated to creating Bland-Altman plots. We validated the tool using 20 datasets with various data distributions by comparing the output from the tool against manually derived results. The webtool handles data that requires a more complex analysis than is commonly available through commercial statistical programs. Moreover, the automated analysis of the data distribution will guide users and help them to correctly plot and analyse their data. The tool agreed perfectly with manually constructed plots. The Bland-Altman graphing tool provides clinical researchers with a tool that correctly analyzes and graphs studies involved in method comparisons. The tool can be accessed here: https://huygens.science.uva.nl/BA-plotteR.

Rank normalization empowers a t-test for microbiome differential abundance analysis while controlling for false discoveries.

A major task in the analysis of microbiome data is to identify microbes associated with differing biological conditions. Before conducting analysis, raw data must first be adjusted so that counts from different samples are comparable. A typical approach is to estimate normalization factors by which all counts in a sample are multiplied or divided. However, the inherent variation associated with estimation of normalization factors are often not accounted for in subsequent analysis, leading to a loss of precision. Rank normalization is a nonparametric alternative to the estimation of normalization factors in which each count for a microbial feature is replaced by its intrasample rank. Although rank normalization has been successfully applied to microarray analysis in the past, it has yet to be explored for microbiome data, which is characterized by high frequencies of 0s, strongly correlated features and compositionality. We propose to use rank normalization as an alternative to the estimation of normalization factors and examine its performance when paired with a two-sample t-test. On a rigorous 3rd-party benchmarking simulation, it is shown to offer strong control over the false discovery rate, and at sample sizes greater than 50 per treatment group, to offer an improvement in performance over commonly used normalization factors paired with t-tests, Wilcoxon rank-sum tests and methodologies implemented by R packages. On two real datasets, it yielded valid and reproducible results that were strongly in agreement with the original findings and the existing literature, further demonstrating its robustness and future potential. Availability: The data underlying this article are available online along with R code and supplementary materials at https://github.com/matthewlouisdavisBioStat/Rank-Normalization-Empowers-a-T-Test.

Predictors of literacy in adulthood: Evidence from 33 countries.

What makes a literate person? What leads to literacy gains and losses within and between individuals and countries? This paper provides new evidence that helps answer these questions. The present comparative analysis of literacy is based on large representative samples from the Survey of Adult Skills conducted in 33 countries, with 25-65 year old participants. We provide, for the first time, estimates of relative importance for a comprehensive set of experiential factors, motivations, incentives, parental influence, demands of workplace, and other predictors of influence. We sketch a configuration of factors that predicts an "ideal" reader, i.e., the optimal literacy performance. Moreover, we discover a pivotal role of the age effect in predicting variability between countries. Countries with the highest literacy scores are the ones where literacy decreases with age the most strongly. We discuss this finding against current accounts of aging effects, cohort effects and others. Finally, we provide methodological recommendations for experimental studies of aging in cognitive tasks like reading.

Estimation of the Number of General Anesthesia Cases Based on a Series of Nationwide Surveys on Twitter during COVID-19 Pandemic in Japan: A Statistical Analysis.

Background and objectives: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread to more than 200 countries. In light of this situation, the Japanese Government declared a state of emergency in seven regions of Japan on 7 April 2020 under the provisions of the law. The medical care delivery system has been under pressure. Although various surgical societies have published guidelines on which to base their surgical decisions, it is not clear how general anesthesia has been performed and will be performed in Japan. Materials and Methods: One of the services provided by the social network service Twitter is a voting function-Twitter Polls-through which anonymous surveys were conducted. We analyzed the results of a series of surveys 17 times over 22 weeks on Twitter on the status of operating restrictions using quadratic programming to solve the mathematical optimizing problem, and public data provided by the Japanese Government were used to estimate the current changes in the number of general anesthesia performed in Japan. Results: The minimum number of general anesthesia cases per week was estimated at 67.1% compared to 2015 on 27 April 2020. The timeseries trend was compatible with the results reported by the Japanese Society of Anesthesiologists (correlation coefficient r = 0.69, p < 0.001). Conclusions: The number of general anesthesia was reduced up to two-thirds during the pandemic of COVID-19 in Japan and was successfully quantitatively estimated using a quick questionnaire on Twitter.

An idea to explore: Visualization of ionization of amino acids using Mathematica.

Ionization of amino acids (AA) is very important concept in biochemistry. We integrate the mathematical concept of probability with biochemically relevant process of AA ionization. We visualize the ionization process with Mathematica software discussing intramolecular interactions between weakly acidic/basic functional groups and charge-pH variation of amino acids in water solution. The visualizations rely on the notion of probability of ionization of functional groups and demonstrate how the extent of ionization and charge varies with pH of the solution. The examples described include amino acids and weak diprotic acids and bases. The aim is to help students better appreciate the importance and consequences of AA ionization and correct some misconceptions.

Nonverbal leadership emergence in walking groups.

The mechanisms underlying the emergence of leadership in multi-agent systems are under investigation in many areas of research where group coordination is involved. Nonverbal leadership has been mostly investigated in the case of animal groups, and only a few works address the problem in human ensembles, e.g. pedestrian walking, group dance. In this paper we study the emergence of leadership in the specific scenario of a small walking group. Our aim is to propose a rigorous mathematical methodology capable of unveiling the mechanisms of leadership emergence in a human group when leader or follower roles are not designated a priori. Two groups of participants were asked to walk together and turn or change speed at self-selected times. Data were analysed using time-dependent cross correlation to infer leader-follower interactions between each pair of group members. The results indicate that leadership emergence is due both to contextual factors, such as an individual's position in the group, and to personal factors, such as an individual's characteristic locomotor behaviour. Our approach can easily be extended to larger groups and other scenarios such as team sports and emergency evacuations.

A novel Chebyshev neural network approach for solving singular arbitrary order Lane-Emden equation arising in astrophysics.

The motivation of this investigation is to develop a single-layer Chebyshev Neural Network (ChNN) model to handle singular fractional (arbitrary)-order Lane-Emden type equations. These equations are well-known application problems of astrophysics and quantum mechanics. Fractional Lane-Emden equations are singular so it is very difficult to solve analytically. Thus, an efficient method is required to handle the above equations. Here, our main aim is to use a single-layer ChNN model for solving fractional Lane-Emden equations. ChNN model is one kind of Functional Link Neural Network (FLNN) in which the hidden layer is replaced by a functional expansion block of the input pattern using orthogonalshifted Chebyshev polynomials (SChP). Thus, the network parameters of ChNN are less than the Multi-Layer Artificial Neural Network (MLANN). We have considered factional-order singular nonlinear problems of astrophysics to show the computational effort of the proposed method. Back Propagation algorithm of the unsupervised version has been considered for minimizing the error function and updating the weights of the ChNN model. Computed results are displayed in terms of tables and graphs.