Variables sociodemográficas, hábitos de vida y niveles de cortisol en adultos de México

El objetivo de la presente investigación fue el analizar si variables demográficas y de hábitos de vida se correlacionan con arcadiano de cortisol salival como un referente normativo para futuras investigaciones. Se analizaron el promedio general y el ciclo circadiano del cortisol en 3.414 muestras salivales, obtenidas en 12 estudios realizados en México, además de que se examinaron las diferencias de dicha hormona con base en las variables de edad, género y consumo o no de cigarros. Se observó un descenso en la concentración de cortisol conforme los participantes avanzaban en edad; asimismo, se identificó un patrón circadiano normal, aunque con niveles superiores en la muestra estudiada; finalmente, no se encontraron diferencias significativas entre las concentraciones de cortisol entre mujeres y hombres, así como entre fumadores y no fumadores. Se discute sobre las implicaciones conceptuales, metodológicas y prácticas que derivan de los hallazgos, tanto para el desarrollo de investigaciones futuras como para su estudio en relación con fenómenos de la salud y la enfermedad. The objective of this research was to determine whether demographic and lifestyle variables correlated with levels of salivary cortisol in a sample of adults in Mexico, and to obtain the average of the circadian cycle of salivary cortisol as a reference for future research. Method. The overall average and the circadian cycle of cortisol were analyzed in 3,414 salivary samples taken in 12 studies in Mexico. Also examined were differences in the aforementioned hormone, based on variables related to age, gender and the consumption or no consumption of cigarettes. Results. A decrease was observed in the concentration of cortisol as the participants advanced in age; also identified was a normal circadian pattern, but with higher levels in the sample studied. Finally, no significant differences were found between the concentrations of cortisol between women and men, or between smokers and non-smokers. Conclusion. Under discussion are the conceptual, methodological implications and practices resulting from the findings, for the development of future research as well as for their study in relation to the phenomena of health and diseaseITESO, A.C

Attachment and survival of viruses on lettuce (Lactuca sativa L. var. capitata L.): role of physicochemical and biotic factors

Enteric viruses are responsible for a significant amount of foodborne disease in the United States. Foodborne disease associated with enteric viruses has been increasing within the last few years due to technological advances and raised awareness. Salads and salad crops are the principal vector for transmission of enteric viruses. The objective of this study was to determine if viruses are able to attach non-specifically to the surface of lettuce and to determine the forces responsible for non-specific viral adsorption to lettuce. Additionally, the impact of the microbial flora on viral persistence was studied to determine the effect on viruses. The four viruses studied were echovirus 11, feline calicivirus, MS2 and ÃÂX174. The viruses were chosen based on their varying isoelectric points and similar physicochemical attributes. The isoelectric point was not the main factor determining virus attachment to lettuce. Viruses had varying attachment efficiencies, with echovirus 11 having the highest affinity to lettuce and ÃÂX174 the least. Viral adsorption to lettuce was mediated by electrostatic forces due to the removal of virus adsorption at pH 7 and 8 with the addition of 1 M NaCl to the buffer solutions. Microcosm studies indicated that the microbial flora did not have a negative impact on virus survival. The bacteriophages had the highest survival rate. Virus survival in the microcosm studies was not indicative of virus survival on the surface of the lettuce. The animal viruses exhibited survival rates greater than or equal to the survival of bacteriophages at 4ð C, but at room temperature viable animal viruses rapidly declined compared to the bacteriophages. Additional studies also indicated that the microbial flora was not able to degrade the viruses for aerobic microbial growth. Overall, these results indicate that viruses are able to attach to the surface of lettuce, providing a possible explanation for the high incidence of virus associated disease involving salads and fresh produce. More importantly the use of surrogates for virus studies involving fresh produce must be re-evaluated, because of the lack of correlation between animal viruses and bacteriophages. Appropriate viral surrogates, if used, have to be carefully chosen based on viral physicochemical properties as well as the infectious route of the virus

Variables sociodemográficas, hábitos de vida y niveles de cortisol en adultos de México

El objetivo de la presente investigación fue el analizar si variables demográficas y de hábitos de vida se correlacionan con arcadiano de cortisol salival como un referente normativo para futuras investigaciones. Se analizaron el promedio general y el ciclo circadiano del cortisol en 3.414 muestras salivales, obtenidas en 12 estudios realizados en México, además de que se examinaron las diferencias de dicha hormona con base en las variables de edad, género y consumo o no de cigarros. Se observó un descenso en la concentración de cortisol conforme los participantes avanzaban en edad; asimismo, se identificó un patrón circadiano normal, aunque con niveles superiores en la muestra estudiada; finalmente, no se encontraron diferencias significativas entre las concentraciones de cortisol entre mujeres y hombres, así como entre fumadores y no fumadores. Se discute sobre las implicaciones conceptuales, metodológicas y prácticas que derivan de los hallazgos, tanto para el desarrollo de investigaciones futuras como para su estudio en relación con fenómenos de la salud y la enfermedad. The objective of this research was to determine whether demographic and lifestyle variables correlated with levels of salivary cortisol in a sample of adults in Mexico, and to obtain the average of the circadian cycle of salivary cortisol as a reference for future research. Method. The overall average and the circadian cycle of cortisol were analyzed in 3,414 salivary samples taken in 12 studies in Mexico. Also examined were differences in the aforementioned hormone, based on variables related to age, gender and the consumption or no consumption of cigarettes. Results. A decrease was observed in the concentration of cortisol as the participants advanced in age; also identified was a normal circadian pattern, but with higher levels in the sample studied. Finally, no significant differences were found between the concentrations of cortisol between women and men, or between smokers and non-smokers. Conclusion. Under discussion are the conceptual, methodological implications and practices resulting from the findings, for the development of future research as well as for their study in relation to the phenomena of health and diseaseITESO, A.C

Efectos de controlabilidad y magnitud de ruido en comportamiento de evitación, cortisol salival y temperatura

Se evaluó el efecto entre magnitud y control de ruido en comportamiento de evitación, cortisol salival y temperatura. Participaron doce hombres entre 18 y 30 años, asignados aleatoriamente a condiciones controlables e incontrolables. Se usó el método ELISA para analizar muestras salivales. Los participantes iniciaron con sesión de pre-mediciones con toma de dos muestras de saliva con 40 minutos de intervalo entre ambas. Posteriormente tuvieron cinco sesiones en que fueron informados que para evitar el ruido deberían presionar dos teclas secuenciadas del teclado de computadora. En la condición incontrolable, ninguna opresión evitaba el ruido. Los participantes tuvieron variaciones de 5 decibeles en cada sesión en torno al umbral de tolerancia en decibeles, determinado previamente (creciente, decreciente o al azar). Durante las sesiones experimentales se obtuvieron muestras salivales y medición de la temperatura periférica antes y después de cada sesión. Finalmente los participantes tuvieron una sesión post-medición. Los resultados mostraron mayor incremento en respuestas, cortisol salival y temperatura en el grupo controlable durante las sesiones experimentales y con mayor frecuencia de respuestas en las últimas sesiones para el grupo incontrolable en subgrupo aleatorio. Se discuten los hallazgos en función del medio ruidoso de los entornos urbanos. This study evaluated the effect of noise magnitude and control on avoidance behavior, levels of saliva cortisol, and temperature. Participants were twelve males between 18 and 30 years old, assigned in incontrollable and controllable randomized conditions. The ELISA test was used for saliva analysis. Two samplings of saliva within a 40 minutes interval were obtained in a pre-measurement session. The experimental phase included five 20 minutes sessions in which the participants were instructed to press two keyboard keys in sequence in order to avoid the noise. On the incontrollable condition, any sequence of keys would not produce avoidance of the noise. In each session, participants received variations of 5 decibels around their tolerance threshold, which was previously obtained (increasing, decreasing or at random). Before and after each of the experimental sessions salivary samples and peripheral temperature measures were obtained. There was also a post-experiment measurement. The results showed more avoidance responses, a higher increment on cortisol and a higher decrement of temperature in the controllable group. On the uncontrollable group, a random subgroup showed increments in responses when magnitude of noise was higher. The findings are discussed in terms of the potential applications in the context of noisy urban areas.ITESO, A.C

Niveles de cortisol y estilo de vida en estudiantes universitarios sanos de México y España

El objetivo de la presente investigación fue identificar si los estudiantes universitarios sanos de Zaragoza, España y Guadalajara, México tienen diferencias en los niveles de cortisol salival y si estas diferencias se pueden atribuir al estilo de vida diferente conformado con base en las prácticas socioculturales del grupo de referencia. Se tomaron muestras salivales y se aplicó el Cuestionario de Hábitos de Vida a 160 estudiantes universitarios. Los resultados mostraron niveles superiores significativamente en cortisol salival de los estudiantes mexicanos con respecto de los estudiantes españoles. Igualmente, se encontraron diferencias significativas en horas de sueño, hora del despertar y consumo de alcohol, pero que no eran capaces de dar cuenta de las diferencias en los niveles de cortisol, salvo en un pequeño porcentaje y en el caso de los estudiantes españoles. Se considera que es necesario seguir investigando otras variables que puedan dar cuenta de estas diferencias socioculturales para diseñar programas educativos que promuevan la salud y prevengan enfermedades. The aim of the study was to analyze if samples of universitary students of México and Spain had different levels of salivary cortisol and if these differences can be an attribution of their life style conformed because of the sociocultural practices of the reference group. 160 universitary students was choosen and they respond the Life-habits Scale and putted a sample of their saliva to analyze the level of cortisol. The results showed that mexican students had higher levels of cortisol than spanish students and this ones had more hours of sleep, they wake up later and drink more alcohol. We found differences too on the hours that they drive on heavy traffic and the level of physical activity. The mexicans drove more and have less activity. These cultural differences in habits could be the cause of differences in cortisol levels in a small percentage in the case of Spanish students. It will be necessary to evaluate the life habits of life and consider the sociocultural characteristics in the design of educational programs directed to promote health and to prevent illness.ITESO, A.C.Universidad de Zaragoz

Partially observable Markov decision processes with partially observable random discount factors

summary:This paper deals with a class of partially observable discounted Markov decision processes defined on Borel state and action spaces, under unbounded one-stage cost. The discount rate is a stochastic process evolving according to a difference equation, which is also assumed to be partially observable. Introducing a suitable control model and filtering processes, we prove the existence of optimal control policies. In addition, we illustrate our results in a class of GI/GI/1 queueing systems where we obtain explicitly the corresponding optimality equation and the filtering process

Variables sociodemográficas, hábitos de vida y niveles de cortisol en adultos de México

Objective. The objective of this research was to determine whether demographic and lifest yle variables correlated with levels of salivary cortisol in a sample of adults in Mexico , and to obtain the average of the circadian cycle of salivary cortisol as a reference for future research. Method. The overall average and the circadian cycle of cortisol were analyzed in 3,414 salivary samples taken in 12 s tudies in Mexico. Also examined were differences in the aforementioned hormone, based on variables related t o age, gender and the consumption or no consumption of cigarettes. Results. A decrease was observed in the concentration of cortisol as the participants advanced in age; also identified was a normal circadian pattern, but with higher levels in the sample studied. Finally, no significant differences were fo und between the concentrations of cortisol between women and men, or between smokers and non-smokers. Conclusion. Under discussion are the conceptual, methodological implications and practices resulting from th e findings, for the development of future research as well as for their study in relation to the phenomena of health and disease.Objetivo. El objetivo de la presente investigación fue el analizar si variables demográficas y de hábitos de vida correlacionan con los niveles de cortisol salival en una muestra amplia de adultos en México. Además de obtener el promedio del ciclo circadiano de cortisol salival como un referent e normativo para futuras investigaciones. Método. Se analizaron el promedio general y el ciclo circadiano del cortisol en 3.414 mu estras salivales, obtenidas en 12 estudios realizados en México, además de que se examinaron las diferencias de dicha hormona con base en las variables de edad, género y consumo o no de cigarros . Resultados. Se observó un descenso en la concentración de cortisol conforme los participantes avanzaban en edad; asimismo, se identificó un patrón circadiano normal, aunque con niveles superiores en l a muestra estudiada; finalmente, no se encontraron diferencias significativas entre las concentraciones de cortiso l entre mujeres y hombres, así como entre fumadores y no fumadores. Conclusion. Se discute sobre las implicaciones conceptuales, metodológicas y prácticas que derivan de los hallazgos, tanto para el desarrollo de investigaciones futuras como para su estudio en relación con fenómenos de la salud y la enfermedad.Escopo . O escopo da presente pesquisa foi analisar se variáveis demográficas e de hábito s de vida correlacionam com os níveis de cortisol salival em uma mostra amplia de adultos no México. Além de obter a média do ciclo circadiano de cortisol salival como um referente normativo para futuras pesqu isas. Metodologia. Foram analisados a média geral e o ciclo circadiano do cortisol em 3,414 mostras sal ivais obtidas em 12 estudos feitos no México, além que foram examinados as diferencias da hormona com base nas variáveis de idade, gênero, e consumo ou não de cigarros. Resultados. Foi observado um descenso na concentração de cortisol conforme a que os participantes avançaram em idade; além, foi identificado um padrão circadiano normal ainda com níveis superiores na mostra estudada; finalmente, não foram achadas di ferencias significativas entre as concentrações de cortisol entre mulheres e homens, assim como entre fumadores e não fumadores. Conclusão . São discutidas as implicações conceptuais, metodológicas e práticas que deri vam das descobertas, tanto para o desenvolvimento de pesquisas futuras como para seu estudo com relação aos fenómenos da saúde e a doença

Application of Sensory Thermography on Workers of a Wireless Industry in Mexico

This study focuses on the application of sensory thermography, as a non-invasive method to evaluate the musculoskeletal injuries that industry workers performing Highly Repetitive Movements (HRM) may acquire. It was made at a wireless company having the target of analyze temperatures in worker's wrists, elbows and shoulders in workstations during their activities, this thru sensorial thermography with the goal of detecting maximum temperatures (Tmax) that could indicate possible injuries. The tests were applied during 3 hours for only 2 workers that work in workstations where there's been the highest index of injuries and accidents. We were made comparisons for each part of the body that were study for both because of the similitude between the activities of the workstations; they were requiring both an immediate evaluation. The Tmax was recorder during the test of the worker 2, in the left wrist, reaching a temperature of 35.088ºC and with a maximum increase of 1.856°C

Calidad en el servicio de los Agentes BCP para clientes de la Región Lima del Banco de Crédito del Perú

En los últimos años, el sector financiero ha ido enfocando esfuerzos en afianzar sus relaciones con los clientes y en mayor medida a mejorar la experiencia de sus clientes, tal es el caso que en la actualidad este objetivo forma parte de los propósitos fundamentes del Banco de Crédito. En ese sentido, es importante un estudio que evalúe la calidad de servicio en los canales de atención enfocado en la experiencia del cliente. Existen varios modelos para medir la calidad de servicio, pero luego de la investigación que se encuentra plasmada en el marco teórico, se ha revisado que SERVQUAL es uno de los más reconocidos y aceptados. Además, se investigó que no existen estudios de validación de este modelo para la calidad del servicio en los agentes bancarios de Lima Metropolitana. Por esta razón, el presente estudio tiene como objetivo validar el modelo SERVQUAL aplicado a los agentes BCP en Lima Metropolitana y enfocado en la apreciación que tienen sus clientes sobre el mismo. Además, implica también la validación de los impactos de cada una de las dimensiones del modelo en la calidad de este canal. Para ello, se aplicó la evidencia estadística necesaria donde se encontró que, tanto las dimensiones de manera independiente como en conjunto, presentan un impacto consistente en la calidad del servicio percibida. A partir de esta información se presentaron las conclusiones y recomendaciones, las cuales permitan ser una base de accionables con el fin de mejorar la calificación del servicio de agentes.In recent years, the financial sector has been focusing their efforts in strengthening their relationship with clients and, largely, improving the experience of their clients. This is one of the main objectives of Banco de Crédito. Therefore, it is important that a study is carried out to evaluate the service quality in the attention channels focused on customer experience. There are several models to measure the service quality, but after the research found in the theoretical framework, it was established that SERVQUAL is one of the most recognized and accepted model. Furthermore, there are no validation studies for this model in bank agents around Metropolitan Lima. The objective of this study is to validate the SERVQUAL model applied to BCP agents around Metropolitan Lima, focusing on the perception of their clients through validation of the impact that their quality model has across their channel. Through statistical evidence it was found that, both dimensions (independent and dependent) have a consistent impact on the perceived service quality. Based on this information, the conclusions and recommendations presented at the end on this study allow for a concrete set of actions to improve the qualification of the service agent

Antimicrobial Resistance Markers of Class 1 and Class 2 Integron-bearing Escherichia coli from Irrigation Water and Sediments

Municipal and agricultural pollution affects the Rio Grande, a river that separates the United States from Mexico. Three hundred and twenty-two Escherichia coli isolates were examined for multiple antibiotic resistance phenotypes and the prevalence of class 1 and class 2 integron sequences. Thirty-two (10%) of the isolates were resistant to multiple antibiotics. Four (13%) of these isolates contained class 1–specific integron sequences; one isolate contained class 2 integron–specific sequences. Sequencing showed that the class 1 integron–bearing strain contained two distinct gene cassettes, sat-1 and aadA. Although three of the four class 1 integron–bearing strains harbored the aadA sequence, none of the strains was phenotypically resistant to streptomycin. These results suggest that integron-bearing E. coli strains can be present in contaminated irrigation canals and that these isolates may not express these resistance markers