Machine learning-based bioimpedance assessment of knee osteoarthritis severity.

This study proposes a multiclass model to classify the severity of knee osteoarthritis (KOA) using bioimpedance measurements. The experimental setup considered three types of measurements using eight electrodes: global impedance with adjacent pattern, global impedance with opposite pattern, and direct impedance measurement, which were taken using an electronic device proposed by authors and based on the Analog Devices AD5933 impedance converter. The study comprised 37 participants, 25 with healthy knees and 13 with three different degrees of KOA. All participants performed 20 repetitions of each of the following five tasks: (i) sitting with the knee bent, (ii) sitting with the knee extended, (iii) sitting and performing successive extensions and flexions of the knee, (iv) standing, and (v) walking. Data from the 15 experimental setups (3 types of measurements×5 exercises) were used to train a multiclass random forest. The training and validation cycle was repeated 100 times using random undersampling. At each of the 100 cycles, 80% of the data were used for training and the rest for testing. The results showed that the proposed approach achieved average sensitivities and specificities of 100% for the four KOA severity grades in the extension, cyclic, and gait tasks. This suggests that the proposed method can serve as a screening tool to determine which individuals should undergo x-rays or magnetic resonance imaging for further evaluation of KOA.

ENDS consumption in students of higher education: Phenomenon on the rise during the COVID-19 pandemic.

INTRODUCTION: The COVID-19 pandemic triggered transformations in the population's lifestyles, including electronic nicotine delivery system (ENDS) consumption. The aim of the study was to determine associations between ENDS consumption habits and lifestyles among higher education students in Bogotá, Colombia. METHODS: This study employed a cross-sectional analytical design, based on a self-administered online survey, conducted in 2021, among students aged 18-59 years. The sample size was 3985 students. Statistical analysis was done through frequency studies, hypothesis testing and a multivariate-penalized logistic regression model (firthlogit), based on the Akaike information criterion (AIC). RESULTS: A total of 3573 students completed the survey, 61.5% were female, 55.3% were young (aged 18-26 years), and 44.6% were adults (aged 27-59 years). The prevalence of ENDS use during the pandemic was 7.3%. Age was negatively associated with ENDS use, as young people had a higher likelihood of using these devices. The likelihood of ENDS use was negative among females (OR=0.38; 95% CI: 0.2-0.5). In contrast, it was positive in students with a history of psychoactive substance abuse and/or dependence (OR=3.59; 95% CI: 1.0-12.0), students who had tried conventional cigarettes (OR=5.12; 95% CI: 3.0-8.5), participants who smoked tobacco during the pandemic (OR=3.15; 95% CI: 2.3-4.2), those who studied virtually (OR=1.52; 95% CI: 1.0-2.3), participants who lived with other ENDS users (OR=3.86; 95% CI: 2.8-5.2) and students with negative perception of impacts on their mental health (OR=1.48; 95% CI: 1.1-1.9). CONCLUSIONS: Being male, aged <26 years, having a history of substance use, having tried conventional cigarettes, pandemic tobacco use, and having lived with other ENDS users, were the main factors associated with pandemic ENDS use. Studying the consumption habits of students in response to lifestyle changes, is fundamental for the formulation of strategies to reduce the development of addictive behaviors, especially in young students during the pandemic.

Representation and practices of Electronic Nicotine Delivery System consumption in the university population of Bogotá(Colombia) / Representación social y prácticas de consumo de sistemas electrónicos de administración de nicotina en población universitaria de bogotá (colombia)

RESUMEN Objetivo: Colombia cuenta con una legislación de control del tabaco desde 2009 sin embargo, no existe una regulación específica sobre los Sistemas Electrónicos de Administración de Nicotina (SEAN), por lo tanto, es vital caracterizar las dimensiones cualitativas de consumo. El objetivo de este estudio fue identificar las prácticas y representaciones de los consumidores de SEAN con el fin de obtener elementos para orientar las acciones necesarias para prevenir su consumo. Materiales y métodos: Este artículo presenta los resultados identificados en el componente cualitativo de una investigación macro sobre la prevalencia del uso de SEAN entre estudiantes universitarios. Se realizaron 14 entrevistas individuales y 1 grupo focal, analizados con el software NVivo10®. Resultados: Se presentan como resultados principales la identificación de las prácticas de consumo, de las cuales se derivó que el núcleo central de la representación social sobre SEAN es no autónomo, lo que posibilita un cambio que desincentive su consumo; el sistema periférico de la representación está conformado por tres elementos: la dimensión social, el consumo de SEAN como estilo de vida y la dimensión corporal y emocional. Conclusiones: Se concluye que las acciones de prevención de consumo de SEAN deben partir de la identificación de características particulares y exclusivas del consumo de SEAN y la incorporación de los elementos del sistema periférico que permitan abordar un consumo que no se basa en la toma de decisiones informadas.

ABSTRACT Objective: Colombia has had a tobacco control legislation since 2009, however there is no specific regulation on Electronic Nicotine Delivery Systems (ENDS). Therefore, it is crucial to characterize the qualitative dimensions of consumption. The study aimed to answer the question: What are the representations and practices of the university population regarding the consumption of SEAN? The objective of the study is to identify the practices and representations of ENDS consumers in order to obtain elements to guide the necessary actions to prevent their consumption. Methods: This paper presents the results identified in the qualitative component of a main study on the prevalence of ENDS use among university students. 14 individual interviews and 1 focus group were conducted and analyzed with the NVivo10® software. The corpus consisted of the transcripts of the 14 interviews and 1 focus group, which constitutes a total of 116 pages of raw data. The techniques used were semi-structured interviews and focus groups, using the Microsoft Teams platform. Taking into account ethical aspects, in each interview and in the focus group the informed consent was read and authorization was requested for the interview to be recorded. The average duration of each interview was one hour and forty-five minutes and the focus group lasted a total of 120 minutes. The capture of practices and representation related to the use/non-use of SEAN was achieved by incorporating two phases of analysis: a)Inductivephase: it was developed with an ordered matrix on the theoretical categories of the project, b)Phase of deductive analysis was carried out based on processes typical of the founded theory that allowed expanding the analytical framework having as its axis the identification of consumption practices and the elements that make up the central core and the peripheral system of representation. Results: The main results are the identification of consumption practices, from which it was derived that the central nucleus of the social representation of SEAN is non-autonomous, which enables a change that discourages its consumption. The reasons and practices for consuming ENDS are closely related to conventional cigarette consumption, which corresponds to the fact that 11 of the 14 interviewees who identify themselves as consumers have consumed conventional cigarettes and only two have been exclusive ENDS consumers. The following practices were identified: a) The consumption motivations were grouped like social, economic and socio-emotional; b) Three types of consumption spaces: prohibited, exclusive and recovered spaces. These last ones are places where you couldn't smoke cigarettes and now they feel empowered to vape; c) There are forms of differential consumption and access to ENDS related to the quality, price, exclusivity and adherence; d) Habits and rituals are not related to moments of daily life, as with cigarettes, but to practices such as searching for and mixing "salts" to obtain flavors, cleaning and maintaining the device, smoking tricks; e) About information channels among the interviewees it was noted that the practice of informed consumption is not frequent and that there are few sources of information that offer low confidence. Finally, the peripheral system of representation is made up of three elements: social dimension, the consumption of SEAN as a lifestyle, bodied and emotional dimension. Conclusion : It is concluded that the actions to prevent the consumption of ENDS should start from the identification of particular and exclusive characteristics of the consumption of ENDS and the incorporation of the elements of the peripheral system that allow addressing a consumption not based on making informed decisions. The main finding is the identification of a non-autonomous representation that stems from the difficulty of establishing notable differentiations between conventional cigarette consumption and e-cigarettes. Therefore, the main vein of research that opens up is to delve into the particular and exclusive characteristics of this consumption. It is essential to incorporate bodily, emotional, and especially social (interpersonal) dimensions as important variables in understanding the practices and representations of e-cigarettes through complex approaches that can break the solid elements on which conventional cigarette consumption is anchored, as it continues to define dynamics of electronic device consumption. It is important at this point to recognize that emotions can be understood as the intermediary between the lived experience in the body and everything that happens in the environment. Thus, it is not possible to think of this representation without recognizing that consumption is an embodied exercise, and the absence of the body in discourses about e-cigarettes can be a revealing element of a disconnection between practices and meanings that are reinforced in the insistence on an action (smoking is smoking) despite the recognition of its negative effects on health (even though it should not be). The understanding of the social representation of e-cigarette consumption in relation to specific practices related to it provides some clues on which to work on processes of information, communication, prevention, and regulation to discourage this consumption that appears relatively new.