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The southern cattle tick Rhipicephalus microplus is a major problem for the cattle industry in tropical and subtropical areas worldwide. Chemical products are commonly applied to control it; however, their indiscriminate use has resulted in the appearance of resistant lineages. In the last decades, plants have been used as an alternative to conventional acaricidal drugs, as several plant compounds repel activity, decrease the reproductive potential and reduce the survival rate of ticks. For this reason, the in vitro efficacy of hexanic and hydroalcoholic extracts of Randia aculeata, Moringa oleifera and Carica papaya were evaluated against the larvae and engorged females of R. microplus. Larval packet tests and adult immersion tests were performed with seven concentrations of each of the extracts. The extracts obtained with hydroethanolic solution (polar solvent) exhibited a higher acaricidal activity than extracts prepared with n-hexane (non-polar solvent). Hydroethanolic extracts of R. aculeata seed and shell showed the highest larvicidal activity against R. microplus (100 and 91% mortality, respectively) at a concentration of 100 mg/mL. Randia aculeata (seed and shell), M. oleifera and C. papaya treatments at the same concentration (100 mg/mL) also resulted in adult mortality of 85, 75, 66 and 55%, respectively. The adult immersion test showed that hydroethanolic extracts derived from R. aculeata seed significantly reduced the index of egg laying and increased the percentage inhibition of oviposition of female ticks at a concentration of 100 mg/mL. These results indicate that the tested extracts exhibit acaricidal activity and could be considered as potential agents for the development of alternative natural acaricides against R. microplus.

The southern cattle tick Rhipicephalus microplus is a major problem for the cattle industry in tropical and subtropical areas worldwide. Chemical products are commonly applied to control it; however, their indiscriminate use has resulted in the appearance of resistant lineages. In the last decades, plants have been used as an alternative to conventional acaricidal drugs, as several plant compounds repel activity, decrease the reproductive potential and reduce the survival rate of ticks. For this reason, the in vitro efficacy of hexanic and hydroalcoholic extracts of Randia aculeata, Moringa oleifera and Carica papaya were evaluated against the larvae and engorged females of R. microplus. Larval packet tests and adult immersion tests were performed with seven concentrations of each of the extracts. The extracts obtained with hydroethanolic solution (polar solvent) exhibited a higher acaricidal activity than extracts prepared with n-hexane (non-polar solvent). Hydroethanolic extracts of R. aculeata seed and shell showed the highest larvicidal activity against R. microplus (100 and 91% mortality, respectively) at a concentration of 100 mg/mL. Randia aculeata (seed and shell), M. oleifera and C. papaya treatments at the same concentration (100 mg/mL) also resulted in adult mortality of 85, 75, 66 and 55%, respectively. The adult immersion test showed that hydroethanolic extracts derived from R. aculeata seed significantly reduced the index of egg laying and increased the percentage inhibition of oviposition of female ticks at a concentration of 100 mg/mL. These results indicate that the tested extracts exhibit acaricidal activity and could be considered as potential agents for the development of alternative natural acaricides against R. microplus.

The classical teaching methodology was based on passive transmission-based learning. The model has changed towards an orientation based on student-centred learning.The objective of the study has been to evaluate the students' perception when learning about urinary tract infections, and their perspective about the teaching imparted on this pathology in the various subjects that include ITU in their syllabus.A cross-sectional analytical study of the responses to an anonymous survey entitled: "Methodology on urine infections. Teaching aspects "issued by 228 students at their fifth year of Medical School, from two promotions. They referred to the following subjects: Pharmacy, Pathophisiology, Gynecology and Obstetrics, Infectious diseases, Microbiology, Nephrology, Pediatrics and Urology.The following variables have been analysed: teaching content, teaching basic aspects of the disease, consideration of teaching methodology and improvement suggestions. Descriptive and inferential statistics were used.The study has concluded that teaching urinary tract infection is perceived in specific subjects related to microorganism (Microbiology), the target organ (Infectious diseases, Urology), affected patients (Pediatrics, Gynecology and Obstetrics) rather than transversal subjects such as Pathophysiology or Pharmacy. The teaching methodology has been considered appropriate by more than 50% of the students in five from the 8 subjects that teach the concept of urinary tract infection. The students suggest convenient changes in current teaching methodology in several subjects that impart the urinary tract infection concept.

Maintenance of the rail track plays an important role in the policies that promote railway transport in the European Union. Each member state has its own railway infrastructure manager that is regulated by the standards set by the European Committee for Standardization (CEN). The standards define three levels for the track geometric quality: the alert limit (AL), the intervention limit (IL), and the immediate action limit (IAL). In the United States, the Federal Railroad Administration (FRA) manages the railroad safety and national rail transportation policy. They classify nine classes of tracks depending on the maximum allowable speed for freight and passenger trains; each classification has its own track geometric limits from nominal values. Usually, track-survey cars are used to measure the parameters of the geometric quality of the tracks in long sectors, whereas traditional surveying methods (TSMs) or an automated measuring system based on a track-surveying trolley assisted by a robotic total...

Several cellular and molecular alterations have been described in skeletal and respiratory muscles of patients with chronic obstructive pulmonary disease (COPD), but information on potential abnormalities of mitochondrial function is scarce. The aim of the present study was to investigate mitochondrial function in the vastus lateralis (VL) and external intercostalis (EI) of COPD patients. Biopsies from VL and EI were obtained during surgery for lung cancer in 13 patients with mild to moderate COPD (age 68+/-6 yrs, forced expiratory volume in one second (FEV(1)) 66+/-15% predicted) and 19 control subjects (age 67+/-9 yrs, FEV(1) 95+/-18% pred). State 3 and 4 mitochondrial oxygen consumption (V'(O(2),m)), ATP synthesis, citrate synthase, cytochrome oxidase (COX) and complex I-III activities, as well as reactive oxygen species (ROS) production, were determined. In COPD patients, in both muscles, COX activity (VL: COPD 3.0+/-0.8 versus control 2.0+/-0.8; EI: 3.7+/-1.6 versus 2.4+/-0.9 micromol min(-1) mg(-1)) and ROS production (VL: 1,643+/-290 versus 1,285+/-468; EI: 1,033+/-210 versus 848+/-288 arbitrary units) were increased, whereas state 3 V'(O(2),m) was reduced (VL: 2.9+/-0.3 versus 3.6+/-0.4; EI: 3.6+/-0.3 versus 4.1+/-0.4 mmol min(-1) kg(-1)). Skeletal muscle mitochondria of patients with chronic obstructive pulmonary disease show electron transport chain blockade and excessive production of reactive oxygen species. The concurrent involvement of both vastus lateralis and external intercostalis suggests a systemic (rather than a local) mechanism(s) already occurring in relatively early stages (Global Initiative for Chronic Obstructive Lung Disease stage II) of the disease.

Petroamazonas EP is the national oil company in Ecuador. It holds most of the oil concessions Onshore and Offshore in the country. The oil and gas production targets require implementing advanced analysis that provides effective results on production.In order to analyze and predict the well Productivity, it is necessary to perform an appropriate perforating analysis; this can be achieved integrating Petrophysics, Geomechanics, Reservoir and Production Domains. For an advanced Perforating design a clear understanding of rock characteristic, depth of damaged zone and reservoir behavior is used in the Perforating simulation. This enhances the right selection of charges and ensures they will overpass the altered zone. Step by step procedure is described:Petrophysical evaluation and rock strength of the formation of interest. Quantification of alteration depth. Display the penetration profile. All this previous steps are used in order to obtain a detailed Flow Profile. To identify and select with the Flow Profile the better zones to produce. A sensitivity analysis is performed to select the best scenario for a technical and economic decision.This methodology was implemented in two of the key Petroamazonas EP assets, which are Amistad Offshore Gas Field, and Apaika Onshore Oilfiled. This helped to optimize and predict the productivity of the wells.The following conclusions were obtained once the wells were on production:Selection of the better intervals to produce Low Uncertainty of well productivity prediction Confirmed effective communication between borehole and reservoir Skin reduction due to a better perforating selection and design Optimized completion design Making proper decisions when analyzing project cost versus production.

Summary We present the results of an open, prospective, multicentric study including 450 patients with mild to moderate Parkinson's disease (PD) converted from standard Sinemet to Sinemet CR (controlled release; Dupont Pharma, Pavia, Italy). Patients with complex fluctuations and diphasic dyskinesias were excluded and the conversion was made after some recommendations, depending on the clinical problems and the daily dosage and administration schedule of standard (STD) Sinemet. The condition of more than 60% of the patients improved after the change and 80% of them preferred the CR formulation by the end of the study. We found a moderate, but significant, improvement in most of the efficacy parameters used, such as the Unified Parkinson's Disease Rating Scale (UPDRS), the Schawb and England scale, and dyskinesias and sleep questionnaires. Forty-five patients (10%) discontinued the study due to adverse effects (mainly gastrointestinal disturbances, functional deterioration, and dyskinesias). We conclude that Sinemet CR is a useful and safe therapeutic option in patients with mild and moderate PD. Selection of the patients is the most important outcome factor.

Describimos el comportamiento estadístico de la significancia de las diferencias en la precipitación en México durante la presencia de "El Niño", "La Niña" o condiciones neutrales. La principal diferencia con otros trabajos similares es el análisis de significancia estadística de las diferencias en la precipitación entre diferentes condiciones del fenómeno El Niño - Oscilación del Sur (ENOS). El análisis se llevó a cabo para la estación húmeda (junio, julio, agosto y septiembre), la estación seca (diciembre, enero y febrero) y para el año completo. Se ajustaron líneas rectas por mínimos cuadrados usando la precipitación como variable dependiente y el valor del Índice Multivariado para el fenómeno ENOS (IME) como variable independiente. Se hicieron también comparaciones de la precipitación entre condiciones de "El Niño", "La Niña" y neutras usando pruebas de Wilcoxon - Mann - Whitney. Los resultados muestran que durante la ocurrencia de "El Niño" la precipitación decrece en la parte sur y se incrementa significativamente en el norte y el noroeste de México. Por el contrario, en condiciones "La Niña", la precipitación se incrementa en el sur y decrece hacia el norte. En la parte central de México las diferencias con respecto a las condiciones neutrales no son significativas. El comportamiento, comparando las estaciones húmeda y seca, es diferente. Durante la época húmeda y con condiciones de "El Niño" la precipitación decrece en el sur y áreas centrales permaneciendo relativamente sin cambios en el norte. Con condiciones "La Niña" y en la estación húmeda la precipitación se incrementa en el sur. Durante la estación seca y en condiciones de "El Niño" la precipitación se incrementa hacia el norte y noroeste mientras que con "La Niña" decrece hacia el sur. El fenómeno ENOS explica en promedio entre 3.7 y 8.9% de la varianza de la precipitación, esto puede deberse a los muchos fenómenos climáticos que la afectan y que lo hacen en una proporción variable y desconocida. Sin embargo hay áreas importantes del país en donde el fenómeno ENOS afecta la precipitación de una manera estadísticamente significativa.

Se propone un modelo estadístico que simule la densidad de probabilidades para la duración de la radiación solar basado en la suposición de que los intervalos de luz solar y de penumbra se distribuyen exponencialmente. Las medidas respectivas t1 y t1 son calculadas para los meses del año y horas del día. A partir de estos parámetros se comparan las simulaciones con las medias. El modelo puede ser descrito como los dos procesos alternativos Poisson. Se reportan histogramas para la duración de la radiación observada.

To analyse the causes that prompted health care professionals to select naltrexone to treat alcoholism. One-year multicentric, prospective study conducted with 221 doctors specialized in alcoholism treatment and analysis of data derived from 1,396 patients attended. Naltrexone was not prescribed to 446 patients. The medical barriers to the prescription of naltrexone included the mode of understanding alcoholism by doctors (20 % of doctors), patients reluctance to take naltrexone (26.9 % of patients), the presence of a concomitant condition (27.6 %) and barriers associated with health care system (6 % of patients). The logistic regression model explained why doctors tended not to prescribe naltrexone when patients had a long course of their disease or had previously received acamprosate.

The sequential cycloaddition of nitroalkenes with methyl vinyl ether was investigated by semiempirical (PM3) and density functional methods (B3LYP/6-31G*). The asymmetric version was also examined with a threoconfigured carbohydrate auxiliary. This produces a larger, more flexible system that complicates the calculation. Most transition structures were then fully optimized at the PM3 level and further refinement was done at ab initio levels. This study represents a model case that enables the rationalization of the high facial selectivity observed in carbohydrate-based nitrone- and nitronate-alkene cycloadditions. The selective endo orientation of the [4+2] pathway results from Coulombic attraction and secondary orbital interactions in the transition state. The stereochemical outcome is largely influenced by a combination of steric shielding from the bulky chiral substituent at C4 and the anomeric effect that places the nitronate C6-alkoxy group in a pseudoaxial arrangement. The resulting conformation favors the subsequent exo approach of methyl vinyl ether to the less hindered re face of the nitronate. It is also remarkable to note that solvation energies stabilize significantly a particular transition structure, thereby explaining the marked stereoselection observed in a polar medium.

Controlled-release levodopa-carbidopa (CRLC) improves some aspects of Parkinson's disease (PD) in patients previously treated with standard levodopa formulations (SL). However, little is known about the effect of this strategy on the health-related quality of life (QoL).To assess the QoL and clinical changes due to the conversion of treatment from SL to CRLC in patients with mild to moderate PD.Through the Nottingham Health Profile (NHP), QoL was measured in 276 non-selected PD patients included in a multicenter, open study. Guidelines for switching to CRLC and optimization of treatment were given. Assessment of patients was carried out by means of the HoehnYahr, UPDRS, and SchwabEngland scales, and questionnaires for dyskinesias and sleep. Examination of the NHP-Spanish Version-scaling properties by fitting data to the Rasch model, disclosed that 3 NHP scales (Emotional reactions, Pain, and Physical mobility) and the NHP distress index (NHPD) were suitable for efficacy analysis.Comparison of scores at baseline and at the end of the study showed significant improvement (paired Student t-test, p0.0001) in all these four scales associated with the change to CRLC. Responsiveness to change of the NHP was high. In the present study, changes in QoL were not contingent to baseline factors such as age, gender, stage of disease or ADL capabilities.Conversion to CRLC significantly improves the QoL of patients with mild to moderate PD.

We present the results of an open, prospective, multicentric study including 450 patients with mild to moderate Parkinson's disease (PD) converted from standard Sinemet to Sinemet CR (controlled release; Dupont Pharma, Pavia, Italy). Patients with complex fluctuations and diphasic dyskinesias were excluded and the conversion was made after some recommendations, depending on the clinical problems and the daily dosage and administration schedule of standard (STD) Sinemet. The condition of more than 60% of the patients improved after the change and 80% of them preferred the CR formulation by the end of the study. We found a moderate, but significant, improvement in most of the efficacy parameters used, such as the Unified Parkinson's Disease Rating Scale (UPDRS), the Schawb and England scale, and dyskinesias and sleep questionnaires. Forty-five patients (10%) discontinued the study due to adverse effects (mainly gastrointestinal disturbances, functional deterioration, and dyskinesias). We conclude that Sinemet CR is a useful and safe therapeutic option in patients with mild and moderate PD. Selection of the patients is the most important outcome factor.

En el presente trabajo se analiza la influencia de la actividad solar en la precipitación pluvial, a partir de series de tiempo de Lituania (1910-1993) y Estonia (1866-1993) y utilizando datos del área de las manchas solares (1866-1993). Por medio de métodos espectrales y autoregresivos, se obtienen ciclos significativos en los procesos solares y terrestres con períodos de 6 y 12 meses y de 2.5 y 11 años. El análisis de las series anuales de precipitación de Estonia y de la superficie de las manchas solares revela cambios en el ciclo de 11 años, cuyo período se muestra reducido a 9 años entre 1915 y 1956; se observa también una oscilación con período de 5 años en las últimas seis décadas. Los co-espectros de los procesos solares y climáticos coinciden con los de otros trabajos y indican la naturaleza común de todos los ciclos y la influencia de la actividad solar en la variabilidad climática. En el presente trabajo se analiza la influencia de la actividad solar en la precipitación pluvial, a partir de series de tiempo deLituania (1910-1993) y Estonia (1866-1993) y utilizando datos del área de las manchas solares (1866-1993). Por medio de métodosespectrales y autoregresivos, se obtienen ciclos significativos en los procesos solares y terrestres con períodos de 6 y 12 meses yde 2.5 y 11 años. El análisis de las series anuales de precipitación de Estonia y de la superficie de las manchas solares revelacambios en el ciclo de 11 años, cuyo período se muestra reducido a 9 años entre 1915 y 1956; se observa también una oscilacióncon período de 5 años en las últimas seis décadas. Los co-espectros de los procesos solares y climáticos coinciden con los de otrostrabajos y indican la naturaleza común de todos los ciclos y la influencia de la actividad solar en la variabilidad climática.

The Task Force on Pulmonary Metastasis Surgery of the Oncology Department of the Madrid Pneumology and Chest Surgery Society designed a questionnaire to determine guidelines for surgery to resect lung metastases in the Autonomous Community of Madrid, an area with over four million inhabitants. The questionnaire was divided into five sections: indications, diagnostic procedures, extension studies, disciplinary foci and surgical techniques. Ten of the hospitals surveyed answered the questionnaire. We found that disagreement is high regarding patient screening, and that there are differences regarding some preoperative procedures and extension studies, as well as in therapeutic approach. Eighty percent of the respondents were not in favor of using video assisted thoracoscopy as a therapeutic technique, and disagreement was greater regarding approaches technique, and disagreement was greater, regarding approaches to bilateral metastases. We infer that between 100 and 120 cases are treated surgically every year. Procedures to join The International Lung Metastases Registry have started.

The chemical composition of atmospheric particles is complex and not completely known. These can be formed by a large variety of elements and chemical compounds, both organic and inorganic, depending on their origin. The chemical composition gives to the particle special characteristics which, in turn, influence its interaction with the various systems where it is involved. Such is the case, for example, of solar radiation in the atmosphere which, by interacting with a particle, can absorb it or disperse it with higher or lower intensity, depending on its size and composition, thereby allowing modification of the earth's climate. Since chemical composition of aerosols depends on their source, and this composition is of great importance insofar as human health is concerned, it is of interest to carry out local studies on this subject. It is in this context in which the present study focused on the identification of chemical elements that are found in the atmospheric particles in the southwestern part of Mexico City. The samples analyzed were collected during the dry and rainy seasons, which characterize the climate of the area. The analyses were made by Scanning Electron Microscopy (SEM) and by Energy Dispersive X-Ray Analysis (EDXRA). Information is alsomore » presented regarding the morphology and size of the observed particles. The results are presented to aid in the chemical characterization of atmospheric aerosols, which is underway by various researchers in different parts of Mexico City. 21 refs., 2 figs., 3 tabs.« less

OBJETIVOS: Describir el perfil de pacientes alcoholicos a los que se prescribe Naltrexona para tratamiento. METODOLOGIA: Prospectiva, para estudio descriptivo transversal. Evalua 802 pacientes mediante cuestionario especificamente disenado. Es aplicado por 401 medicos durante la primavera y verano de 1998. RESULTADOS: Predominio de 4 hombres por mujer, edad promedio de 41’6 anos, residentes en ciudad (75%), con su familia (77%) y trabajadores activos (50%). Sus alcoholismo tiene una evolucion de 14’9 anos. Beben preferentemente destilados (63’3%) cerveza (57’8%) y vino (52%). Frecuentemente refieren “perdida de control” (66’2%), tomar 25-100 Bebidas (UBE) por semana y una cuarta parte mas de 15 UBE al dia. Un 83% presentaba otra psicopatologia asociada y el 33’2% historia de abuso de drogas. DISCUSION: Perfil clinico desplazado con respecto al grupo general de alcoholicos en el sentido de ser una poblacion mas joven, con cierta preservacion del funcionamiento social, laboral y familiar y con un tiempo de evolucion menor. Destaca la alta frecuencia de la presencia de “perdida de control” en estos pacientes como criterio de seleccion.

Preliminary results about the organic fraction, soluble in benzene, of the atmospheric aerosol are presented. 29 air samples taken at Ciudad Universitaria (Mexico City), between July 79 and August 80, were analyzed. The results indicate a variation with naxiu concentrations during December and January, and minimum during June, July and August; the concentration distribution is log-normal with a geometrical mean of 7.12µg/m3 and standard geometrical deviation of 1.81 µg/m3.

A partir de mediciones actinométricas efectuadas en la Ciudad de México desde octubre 1974, hasta marzo 1975, se han detectado valores altos de extinción producidos por aerosoles. Substrayendo los valores básicos debidos a la capa "normal" contaminada de la bruma de la ciudad, se obtienen valores de turbidez que indican una reducción media local de la transferencia atmosférica de 2.6%. Observaciones visuales apoyadas con fotografías de crepúsculos brillantes y coloreados percibidos unos 35-40´después del ocaso son consistentes con los reportes previos de Meinel y Meinel y Volz, entre otros, de la gran difusión de la capa de polvo volcánico originada por erupciones ocurridas entre el 13 y 23 de octubre de 1974 en el Volcán de Fuego de Guatemala.

A generalized model has been developed for the prediction of pressure drop and flooding in packed columns in which gas and liquid flow countercurrently. The model has been validated for a wide variety of packings, both random and structured. A single mathematical expression is used to describe all flow regimes: dry gas, irrigated gas flow below the load point, loading region, and flooding. The approach to the model development is fundamental in character and is an improvement over models published earlier.

Se describe un método para la evaluación de la cantidad total de partículas suspendidas en una columna vertical, de aire de sección unitaria. El método está basado en un modelo de extinción de radiación solar por aerosoles en la atmósfera. Los resultados se comparan con el coeficiente de turbiedad de Angstrom. Usando la concentración de partículas en superficie y suponiendo un decaimiento exponencial de la concentración de partículas, se establece la escala de altura para la distribución vertical del aerosol. Por último, aprovechando el modelo de atenuación, se realizaron algunos experimentos numéricos que permiten evaluar el efecto de los diferentes componentes atmosféricos considerados en el modelo, tales como la cantidad de partículas, el agua precipitable, la abundancia de bióxido de carbono y la cantidad total de ozono atmosférico.

The concentrations of Cd and Pb at Ciudad Universitaria have increased by 1.4 and 3.6, times respectively, during the last two years. Cu, Zn and Cd show a seasonal variation and follow the atmospheric turbidity pattern of Mexico City (19o20' N, 2,268 m. a. s. l.). Fe and Pb behave randomly during the whole year. The concentrations of Fe, Cd and Pb show a log-normal distribution; those of Cu and Zn differe from this type of distribution. These results were obtained from atmospheric aerosol samples collected during 14 months (July 1979 - August 1980) at the Atmospheric Radiation Observatory of Ciudad Universitaria, located in the southern part of Mexico City. 59 samples selected at random were analyzed by the atomic absorption method and the concentrations of five heavy metals were determined.

In 78 patients a total of 89 chest wall tumours were considered for surgery between 1960 and 1982. There were 63 neoplasms (12 benign, 51 malignant) and 26 pseudotumours (1 chest wall deformity, 6 inflammatory tumours and 19 hydatid cysts of the chest wall). Radical resection of some kind was possible for 67 tumours and 2 patients underwent palliative resection. Exploratory thoracotomy and biopsy were performed in 9 patients and thoracoscopy and biopsy in 10. One hydatid cyst was managed with mebendazole. There were 11 postoperative complications and three hospital deaths. Chest wall prostheses were used in 13 patients. There was no operative mortality. The mean survival time for the patients with malignant tumour was 12.3 months in pleural mesothelioma and in metastatic pleural tumours, 15.2 months in primary rib tumours and 6.4 months in metastatic rib tumours. There was one death in the benign tumour group and one in the pseudotumour group.

It is presented a case of spontaneous rupture of the union cardioesophageal consecutive on ingestion of bicarbonate in an old patient with strangulated hiatal hernia. It is analyzed the phisiopathological factors of such complication and the surgical treatment employed.