Heartbeats Do Not Make Good Pseudo-Random Number Generators: An Analysis of the Randomness of Inter-Pulse Intervals

The proliferation of wearable and implantable medical devices has given rise to an interest in developing security schemes suitable for these systems and the environment in which they operate. One area that has received much attention lately is the use of (human) biological signals as the basis for biometric authentication, identification and the generation of cryptographic keys. The heart signal (e.g., as recorded in an electrocardiogram) has been used by several researchers in the last few years. Specifically, the so-called Inter-Pulse Intervals (IPIs), which is the time between two consecutive heartbeats, have been repeatedly pointed out as a potentially good source of entropy and are at the core of various recent authentication protocols. In this work, we report the results of a large-scale statistical study to determine whether such an assumption is (or not) upheld. For this, we have analyzed 19 public datasets of heart signals from the Physionet repository, spanning electrocardiograms from 1353 subjects sampled at different frequencies and with lengths that vary between a few minutes and several hours. We believe this is the largest dataset on this topic analyzed in the literature. We have then applied a standard battery of randomness tests to the extracted IPIs. Under the algorithms described in this paper and after analyzing these 19 public ECG datasets, our results raise doubts about the use of IPI values as a good source of randomness for cryptographic purposes. This has repercussions both in the security of some of the protocols proposed up to now and also in the design of future IPI-based schemes.This work was supported by the MINECO Grant TIN2013-46469-R (SPINY: Security and Privacy in the Internet of You); by the CAMGrant S2013/ICE-3095 (CIBERDINE: Cybersecurity, Data and Risks); and by the MINECO Grant TIN2016-79095-C2-2-R (SMOG-DEV: Security Mechanisms for fog computing: advanced security for Devices). This research has been supported by the Swedish Research Council (Vetenskapsrådet) under Grant No. 2015-04154 (PolUser: Rich User-Controlled Privacy Policies)

Influencia del entorno donde se habita (rural vs

Introducción El objetivo de este estudio fue valorar la influencia del entorno donde se habita (rural vs urbano) sobre la condición física y parámetros antropométricos en estudiantes de educación primaria. Material y método Se seleccionaron 509 sujetos (290 urbanos y 219 rurales) de entre 8 y 11 años, a los que se les realizó una valoración antropométrica (masa, talla, IMC, ratio cintura/cadera) y de la condición física (fuerza de prensión manual, salto vertical, flexibilidad y fitness cardiorrespiratorio). Resultados Los resultados muestran que la población urbana obtiene valores más bajos en parámetros antropométricos, y la población rural mejores resultados en condición física: fuerza de prensión manual (15,72 ± 4,10 vs 19,78 ± 5,20 kg), flexibilidad (8,38 ± 4,59 vs 17,08 ± 6,24 cm) y fitness cardiorrespiratorio (46,00 ± 4,19 vs 46,79 ± 4,49 ml/kg/min), no existiendo diferencias para el salto vertical. Conclusiones Se pone de manifiesto que el lugar de residencia (rural vs urbano) se debe tener en cuenta a la hora de aplicar programas de intervención para la promoción de la actividad física

Influència de l’entorn on es viu (rural vs urbà) sobre la condició

Introducció L’objectiu d’aquest estudi fou valorar la influència de l’entorn en què es viu (rural vs urbà) en la condició física i els paràmetres antropomètrics d’escolars d’educació primària. Material i mètode Es seleccionaren 509 subjectes (290 urbans i 219 rurals) de 8 a 11 anys, als quals es féu una valoració antropomètrica (massa, talla, IMC, ràtio cintura/maluc) i de la condició física (força de prensió manual, salt vertical, flexibilitat i fitnes cardiorespiratori). Resultats Els resultats mostren que la població urbana obté valors més baixos en els paràmetres antropomètrics i la població rural millors resultats en la condició física: força de prensió manual (15,72 ± 4,10 vs 19,78 ± 5,20 kg), flexibilitat (8,38 ± 4,59 vs 17,08 ± 6,24 cm) i fitnes cardiorespiratori (46,00 ± 4,19 vs 46,79 ± 4,49 ml/kg/min), i no es trobaren diferències en el salt vertical. Conclusions Es posa de manifest que cal tenir en compte el lloc de residència (rural vs urbà) a l’hora d’aplicar programes d’intervenció de promoció de l’activitat física

Efectos del neoliberalismo en la ganadería bovina lechera del municipio Marcos Castellanos, región fronteriza Lerma Ciénega, Jalisco-Michoacán, México

El objetivo de esta investigación es analizar las consecuencias que ha traído la imposición del modelo económico neoliberal en las actividades de los productores de ganado bovino lechero del municipio de Marcos Castellanos, Michoacán. Se utilizó una metodología de redes que consistió en identificar a actores clave en el municipio, a quienes se les aplicaron entrevistas semiestructuradas en sesiones grupales. Esta investigación muestra la crisis que atraviesan los productores de Marcos Castellanos, Michoacán —una de las municipalidades de mayor producción de leche en el estado—, la cual ha provocado desánimo entre los productores, orillándolos en su mayoría a vender su ganado para buscar otras formas de subsistencia. Los resultados nos permiten concluir que la crisis económica ocasionada por las políticas implementadas bajo el modelo neoliberal ha impactado de manera negativa en los productores lecheros de Marcos Castellanos, Michoacán, en las últimas dos décadas, particularmente en los tres primeros años del gobierno lopezobradorista, cuya administración ha abandonado al sector ganadero

Predicting Big Data Adoption in Companies With an Explanatory and Predictive Model

The purpose of this paper is to identify the factors that affect the intention to use Big Data Applications in companies. Research into Big Data usage intention and adoption is scarce and much less from the perspective of the use of these techniques in companies. That is why this research focuses on analyzing the adoption of Big Data Applications by companies. Further to a review of the literature, it is proposed to use a UTAUT model as a starting model with the update and incorporation of other variables such as resistance to use and perceived risk, and then to perform a neural network to predict this adoption. With respect to this non-parametric technique, we found that the multilayer perceptron model (MLP) for the use of Big Data Applications in companies obtains higher AUC values, and a better confusion matrix. This paper is a pioneering study using this hybrid methodology on the intention to use Big Data Applications. The result of this research has important implications for the theory and practice of adopting Big Data Applications

Questionnaire : Loss of Entertainment in Spanish Futsal (PEFSE)-Results Analysis

In the absence of questionnaires addressing the analysis of the rule’s change in futsal and the need to find an instrument that is capable of carrying out this objective, the aim of this study is to design and develop a questionnaire to assess the loss of entertainment in futsal. To do this, the sample consisted of 279 subjects with roles as a coach, player, physiotherapist, amateur referee and journalist since all of them are part of the sport. The instrument is based on the new rules imposed by FIFA in the kick-in and corner and their impact on the show. This descriptive cross-sectional study where is designed and implemented a closed-responses ad hoc questionnaire to subjects related with futsal in the first category to obtain objective information was undertaken. The analysis of data showed satisfactory results in terms of reliability and validity. It can be concluded that this scale is valid and reliable instrument to analyze changes in the rules of futsal

CONCEPTO DE COEDUCACIÓN EN EL PROFESORADO DE EDUCACIÓN FÍSICA Y METODOLOGÍA UTILIZADA PARA SU TRABAJO

The aim of this research was to know the general conception of Physical Education teachers about the coeducation in their own subjects and to find out which methodological strategies are followed by the teachers to work with coeducation. Some semi structured interviews were done to ask for the content analysis. To stand out: in the category “Coeducation definition”, there isn't any arrangement by the professorate about what coeducation is. The category “Drive space employment” shows up that the kids use the most part of the space. The category “Language” stands out that the teachers admit that a sexist way of speaking is inadvertently used in the schools by the kids.  El objetivo de esta investigación fue conocer cual es la concepción general del profesorado de Educación Física (EF) sobre la coeducación en EF y que estrategias metodológicas utiliza el profesorado para trabajarla. Se realizaron entrevistas semiestructuradas sometidas a análisis de contenido. Se destaca que; la categoría “Definición de coeducación” no existe unanimidad en el profesorado sobre que es la coeducación. La categoría “Utilización del espacio motriz” pone de manifiesto que los chicos utilizan la mayoría del espacio. La categoría “Lenguaje”, resalta que el profesorado admite que existe un lenguaje sexista en los centros escolares pero que su uso es inconsciente.O objetivo desta investigação consistiu em conhecer qual é o conceito geral dos professores de Educação Física (EF) sobre educação mista em EF e que estratégias metodológicas utilizam os professores para trabalhar. Foram realizadas entrevistas semiestruturadas, procedendo-se análise do seu conteúdo. Destaca-se que, na categoria "Definição de coeducação" não existe um consenso entre os professores sobre o que é coeducação. A categoria "Uso de espaço motriz" revela que os meninos usam a maioria do espaço. A categoria "Linguagem" enfatiza que os professores admitem que exista uma linguagem sexista nas escolas, porém o seu uso é inconsciente.

Effects of Eight Years of Collecting on the Persistence of Liometopum apiculatum Ant Nests in Rangelands of Charcas, San Luis Potosí, Mexico

In Mexico, the pupae of the reproductive castes of the ant Liometopum apiculatum, escamoles, are highly valued in traditional and gourmet cuisine in the country’s central region. Escamoles are collected during the dry season of the year. The recommended collecting process is to open the ant nest by removing soil until the rearing chamber and the trabeculae with attached escamoles are found. A well-managed ant nest can be collected repeatedly for approximately 12 to 40 years. In Charcas municipality, San Luis Potosí, Mexico, 400 ant nests were located and checked under two land tenure conditions: the Laguna Seca private ranch and the Pocitos communal ejido. The exploitation of escamoles on both tenures was characterized by recording the number of dead and live ant nests. This work evaluated the condition of the ant nests registered in 2012 after eight years. The hypothesis was that ant nests’ survival would be greater in the private than in the communal land. The percentage of living ant nests on the ejido decreased by 35.67%. In contrast, on the ranch, it was 26.88%. The percentage of relocated ant nests was lower on the ejido, 37.43%, compared to the ranch, which was 48.1%. The number of dead ant nests on the ejido increased to 33.51% and on the ranch 15.0%. As predicted by the hypothesis, ant nest survival was higher on the private ranch than on the communal ejido lands because of stronger control of the extraction process

Implementación de la telemedicina en la asistencia sanitaria pediátrica durante la pandemia COVID-19

Introducción: La pandemia COVID-19 ha supuesto un retosocial, económico, pero sobre todo sanitario. La consulta telefónica que se inició durante el confinamiento, inicialmente en atención primaria y después, con la relajación de las medidas, en la atención hospitalaria, se ha implementado como opción asistencial. Se ha elaborado un estudio para intentar conocer la satisfacción de las familias y de los profesionales, así como aspectos de seguridad de esta opción asistencial. Materialy métodos: Se llevóa cabo una encuesta anónima afamiliares depacientes pediátricos y a profesionales sanitarios que recibieron y prestaron asistencia de manera telefónica entre mayo y diciembre de 2020 en un hospital de segundo nivelasistencial. Las variables se recogieron y analizaron mediante Excel y SPSS. Resultados: Las familias valoraron positivamente la atención en el 89,6 %yal 73,5 % le gustaría seguir teniendo un modelo de atención mixta e integrarían otros elementos de telemedicina. El 91,9 % entendiócorrectamente las explicaciones.Respecto a los profesionales sanitarios, el 85,7% estuvo de acuerdo con el sistema de atención mixto. Al 76,1% la consulta le resulta más eficiente, pero solo el 33% incrementaría la proporción de este tipo de consultas. El 52% creen que esta atención no repercute en la seguridad del paciente, aunque el 61,9% cree que sí lo hace negativamente en la formación de los médicos internos residentes. Conclusiones: Existe un elevado grado de satisfacción de pacientes y profesionales, estando ambos predispuestos a continuar con este modelo asistencial. Parece que la pandemia por SARS-CoV2ha impulsado la instauración definitiva de la telemedicina en las consultas pediátricas hospitalarias.Introduction and objectives:The COVID-19 pandemic has been a social, economic but above all health challenge. The telephone consultation that began during confinement, initially in primary care and later, with the relaxation of the measures, in hospital care, has been implemented as a care option. This study has been carried out to analyze the satisfaction of families and professionals as well as safety aspects of this care option. Material and methods:An anonymous survey was carried out on patients and health professionals who received and provided assistance by telephone between May 2020 and December 2020 in a second level hospital. The variables were collected and analyzed using Exceland SPSS. Results:89.6% of the families valued the care positively. 91.9% of them correctly understood the explanations. In addition, 73.5% of the families would like to continue having a mixed care model and would integrate other elements of telemedicine. Regarding healthprofessionals, 85.7% of them agreed with the mixed care system. For 76.1% of them, this model is more efficient, but only the 33% of them would increase telehealth. The 52% of professionals believe that this new model does not affect patient safety, although 61.9% of them believe that it does negatively affect the training of internal medical residents. Conclusions: There is a high degree of satisfaction of patients and professionals, both being predisposed to continue with this care model. It seems that the COVID-19 pandemic has prompted the definitive establishment of telemedicine in hospital pediatric consultations

Substrate-induced dimerization of engineered monomeric variants of triosephosphate isomerase from Trichomonas vaginalis

"The dimeric nature of triosephosphate isomerases (TIMs) is maintained by an extensive surface area interface of more than 1600 angstrom 2. TIMs from Trichomonas vaginalis (TvTIM) are held in their dimeric state by two mechanisms: a ball and socket interaction of residue 45 of one subunit that fits into the hydrophobic pocket of the complementary subunit and by swapping of loop 3 between subunits. TvTIMs differ from other TIMs in their unfolding energetics. In TvTIMs the energy necessary to unfold a monomer is greater than the energy necessary to dissociate the dimer. Herein we found that the character of residue I45 controls the dimer-monomer equilibrium in TvTIMs. Unfolding experiments employing monomeric and dimeric mutants led us to conclude that dimeric TvTIMs unfold following a four state model denaturation process whereas monomeric TvTIMs follow a three state model. In contrast to other monomeric TIMs, monomeric variants of TvTIM1 are stable and unexpectedly one of them (I45A) is only 29-fold less active than wild-type TvTIM1. The high enzymatic activity of monomeric TvTIMs contrast with the marginal catalytic activity of diverse monomeric TIMs variants. The stability of the monomeric variants of TvTIM1 and the use of cross-linking and analytical ultracentrifugation experiments permit us to understand the differences between the catalytic activities of TvTIMs and other marginally active monomeric TIMs. As TvTIMs do not unfold upon dimer dissociation, herein we found that the high enzymatic activity of monomeric TvTIM variants is explained by the formation of catalytic dimeric competent species assisted by substrate binding.