Monitoring anaerobic sequential batch reactors via fractal analysis of pH time series.

Efficient monitoring and control schemes are mandatory in the current operation of biological wastewater treatment plants because they must accomplish more demanding environmental policies. This fact is of particular interest in anaerobic digestion processes where the availability of accurate, inexpensive, and suitable sensors for the on-line monitoring of key process variables remains an open problem nowadays. In particular, this problem is more challenging when dealing with batch processes where the monitoring strategy has to be performed in finite time, which limits the application of current advanced monitoring schemes as those based in the proposal of nonlinear observers (i.e., software sensors). In this article, a fractal time series analysis of pH fluctuations in an anaerobic sequential batch reactor (AnSBR) used for the treatment of tequila vinasses is presented. Results indicated that conventional on-line pH measurements can be correlated with off-line determined key process variables, such as COD, VFA and biogas production via some fractality indexes.

Prevalencia del tabaquismo y sintomatología asociada en estudiantes de Medicina de la Universidad Juárez Autónoma de Tabasco (México) / No disponible

Objetivo: Investigar la prevalencia, características y sintomatología relacionada al consumo de tabaco en estudiantes de medicina de la Universidad Juárez Autónoma de Tabasco (UJAT), México. Métodos: Se trata de un estudio observacional, transversal y descriptivo realizado en una muestra aleatoria, a la cual se le aplicó un cuestionario que contenía variables relacionadas con el hábito de fumar y los síntomas y signos manifestados. Resultados 58,4% de los estudiantes encuestados refirieron haber fumado al menos una vez en su vida; de éstos, el 27,1% refirió continuar fumando. Los fumadores que consumían más de 10 cigarrillos al día presentaron mayor riesgo de manchas en los dientes, OR de 9,38 (IC95% 1,42, 6,07). Conclusiones. La prevalencia del hábito de fumar en los estudiantes de medicina de la UJAT es menor que la reportada por otra universidad de México, pero mayor que la del estudio realizado en estudiantes argentinos (AU)

Objective: To investigate the prevalence, characteristics and symptomatology related to the tobacco consumption in medicine students of the Universidad Juárez Autónoma de Tabasco. (UJAT), Mexico. Methods: We made an observational, cross-sectional and descriptive study, developed in a random sample; to which a questionnaire was applied. Wich contained variables related to the smoking habit and the symptoms and signs showed. Results: 58,4% of the students declared to have smoked at least once in their life, of these the 27,1% referred to continue smoking. The smokers who consumed more than 10 cigarettes a day, showed greater risk of spots in teeth OR of 9,38 (IC 95% 1,42, 62,07). Conclusions. The prevalence of the smoking habit in medicine students of the UJAT is lower than the one reported by another university of Mexico, but higher than the one of a study made in Argentine students (AU)

[Renal plasmacytoma. Report of a new case]. / Plasmocitoma renal. Presentación de un nuevo caso.

OBJECTIVE: To present a case of extramedullary plasmacytoma localized in the kidney. The clinical features, diagnostic tests, treatment and outcome are discussed. METHODS/RESULTS: A 59-year-old patient presented with a right renal mass and renal failure. The complementary tests showed a lambda monoclonal band in blood and urine, and a left renal biopsy showed changes compatible with myeloma. The definitive diagnosis of plasmacytoma was based on the findings of open renal biopsy since fine needle punction findings were compatible with a carcinoma. The patient received polychemotherapy, but died one year after the diagnosis due to a rapidly progressing plasmatic cell dyscrasia. CONCLUSION: Renal plasmacytoma is rare and should be suspected when paraprotein is detected in blood and urine, and when the patient has a history of plasmatic cell dyscrasia. There is no widely-established treatment. Surgery, radiotherapy or chemotherapy, alone or in combination, can be utilized.

[Prevalence of malnutrition in minors under 5 years of age in Tabasco]. / Prevalencia de desnutrición en menores de cinco años de Tabasco.

OBJECTIVE: To evaluate malnutrition prevalence in children under five years-old in Tabasco, Mexico, during 1996, and their evolution in 1991-1996. MATERIAL AND METHODS: A cross-sectional study, including 1,256 children under five years-old in 593 communities (31 urban and 562 rural) from 17 sanitary districts. RESULTS: The weight/age indicator for malnutrition in children under five years old showed 59% of children had normal nutrition and 41% with malnutrition, distributed as follows: 26.12% slight, 12.62% moderate and 2.39% severe. In children between 1-5 years old, malnutrition prevalence was 45%. CONCLUSIONS: The number of children with malnutrition in Tabasco during the study period (1991-1996) has decreased in proportion to the increase of those with normal nutrition. Based on the health system activities, the number of health districts with critical malnutrition indicators decreased from 6 to 4.

[Prevalence of malnutrition in preschool children in Tabasco, Mexico]. / Prevalencia de desnutrición en preescolares de Tabasco, México.

Childhood malnutrition is an important and prevailing public health problem in Tabasco, Mexico, where precise information is still lacking. Tabasco Public Health Department has been working on this problem since 1991. The first nutritional survey was carried out to recognize the nutritional level of 935 randomly selected children between 1-4 years of age in 17 municipalities of the state. A proportion of 46% of childhood malnutrition level was found in this Mexican state (29.8 low, 12.8% moderate and 3.4% severe). Ninety percent of severe childhood malnutrition cases were located in the rural municipalities of Tacotalpa, Nacajuca, Jonuta, Macuspana and Centla. These municipalities were more affected, with a malnutrition prevalence of 63%, 62.2%, 60%, 59.5% and 59.4%, respectively. Results from these surveys identify high risk areas and may serve to advance specific proposals for nutrition interventions.

[Prevalence of tuberculous infection among health personnel]. / Prevalencia de la infección tuberculosa en el personal sanitario.

One or more tuberculin skin tests (PPD) were carried out in 1865 members of the health care staff (71%) of the Hospital Clinic from Barcelona, so as to detect the prevalence of the infection and, particularly, to identify the converters (recently infected individuals) for the recommendation of antituberculous chemoprophylaxis. A higher number of converters was found in the group with higher risk of contagion owing to professional exposure, but the differences were not statistically significant. Significant differences were not found, either, between infected and noninfected individuals classified in risk groups. In the 1865 surveyed individuals, the initial and successive (when performed) PPD testings were negative in 987 (52%). In 775 individuals (41%), PPD reaction was positive in the initial testing. In the remaining 103 (5%), PPD reactions became positive after an initial negative result (converters). 50% of the 775 individuals with positive PPD reaction were over 35 years of age. The rate of infected individuals (positive PPD reaction) and converters was not significantly higher in those health care professionals with a supposed higher degree of exposure to infection.