Coordination copolymerization monitoring of ethylene and alfa-olefins by in-line Raman spectroscopy.

Copolymerizations of ethylene and alfa-olefins, using Ziegler-Natta or metallocene catalysts, testing two methods of co-monomer addition, through batch or dossing mode during the reactions, are reported in this work. Copolymerizations are monitored by in line Raman spectroscopy, comparing the effect of the kind of catalyst and the co-monomer addition modes on the chemical composition of the copolymers produced. The global co-monomer composition is determined by 13C NMR spectroscopy, compared with the monitoring by Raman spectroscopy along the reactions, where it is possible to define homogeneous or heterogeneous co-monomer distributions. Batch addition achieves higher incorporations of co-monomers, compared to dosed addition, where it is possible to determine the maximal co-monomer addition without affecting activities by transfer reactions. The incorporation mode of alfa-olefins in this type of reaction has been little reported, and until it is known, there is no rapid technique available to determine the uniformity of the co-monomer incorporations in real time. Copolymerization kinetics are also reported here and correlated to the addition method of the comonomers in both kinds of reactions. Homogeneous and heterogeneous co-monomer incorporations promoted by a single site catalyst (metallocene) or multisite system (Ziegler-Natta) is related to the homogeneous or heterogeneous co-monomer distributions detected by Raman spectroscopy, using each kind of catalytic system.

An aggregate score to stratify the technical complexity of video-assisted thoracoscopic lobectomy.

OBJECTIVES: The purpose of this study was to develop a score to predict the complexity of video-assisted thoracoscopic surgery (VATS) lobectomies preoperatively. METHODS: One hundred and thirty-nine consecutive patients undergoing VATS lobectomy operated on by a single surgeon as the first operator were included. Complex operations were defined as: operation time >180 min (corresponding to the 75th percentile) or a conversion to thoracotomy. Several patient-related baseline and radiological variables were tested for a possible association with surgical complexity by logistic regression analysis. An aggregate score was created by weighing the regression estimates of the significant predictors. Patients were then grouped in classes of risk according to their scores. Finally, the score was validated in an external population of 154 VATS lobectomy patients. RESULTS: Twenty-nine VATS lobectomies (21%) were classified as complex. The following variables were found to be significantly associated with a complex operation and were used to calculate the risk score in each patient (1 point each): male (P = 0.006), presence of thick pleura (P = 0.003), presence of emphysema (P = 0.001), enlarged hilar nodes (P = 0.003). Patients were grouped in 4 classes showing an incremental incidence of complex operations (P < 0.0001): score 0, 7.4%; score 1, 18%; score 2, 27%; score >2, 67%. In the external validation set, the score confirmed its association with the incidence of complex operations (P < 0.001): score 0, 7.3%; score 1, 10%; score 2, 16%; score >2 50%. CONCLUSIONS: The complexity score appeared to be reproducible in an external setting and can be used to preoperatively identify appropriate candidates for VATS lobectomies to improve the efficiency and safety of the training phase.

The National Institutes of Health Fogarty International Center Global Health Scholars and Fellows Program: Collaborating Across Five Consortia to Strengthen Research Training.

As demand for global health research training continues to grow, many universities are striving to meet the needs of trainees in a manner complementary to research priorities of the institutions hosting trainees, while also increasing capacity for conducting research. We provide an overview of the first 4 years of the Global Health Program for Fellows and Scholars, a collaboration of 20 U.S. universities and institutions spread across 36 low- and middle-income countries funded through the National Institutes of Health Fogarty International Center. We highlight many aspects of our program development that may be of interest to other multinational consortia developing global health research training programs.

Estudio comparativo entre deportes simétricos y asimétricos mediante análisis estructural estático en deportistas adolescentes / Comparative study between symmetrical and asymmetrical sports by static structural analysis in adolescent athletes

En los exámenes médicos preparticipación deportiva, el análisis de las estructuras anatómicas que no están directamente relacionadas con el deporte en cuestión, suele ser más superficial. Un examen más detallado del aparato locomotor podría revelar la existencia de ciertas anomalías que, en ocasiones pueden pasar desapercibidas. El objetivo de este estudio es describir la prevalencia de trastornos estructurales del aparato locomotor en una población de deportistas adolescentes de élite de la Comunidad de Madrid. Establecer la relación de alteraciones con la práctica de deportes simétricos o asimétricos. Estudio transversal descriptivo. Nivel de evidencia II-III. Nuestra población de estudio incluye deportistas pertenecientes al plan de tecnificación de la Comunidad de Madrid: 102 deportistas, 66 hombres y 36 mujeres con edades comprendidas entre 12 y 19 años. Un grupo control está compuesto por deportistas de natación, deporte considerado simétrico y el segundo grupo por deportistas practicantes de deportes considerados asimétricos: esgrima y bádminton. Los deportistas fueron examinados siguiendo un método cegado por tres diferentes especialistas que utilizaron el mismo protocolo. Se ha empleado el contraste de hipótesis para variables cualitativas, con un nivel de confianza del 95% (p<0,05). Noventa y seis deportistas (94,1%) presentaron algún tipo de alteración estructural y /o postural en los exámenes médicos preparticipación deportiva. No encontramos correlación significativa (p<0,05) ) entre los diferentes deportes en las alteraciones en la columna vertebral, las rodillas, las extremidades y la huella plantar, independientemente fueran simétricos o asimétricos (p<0,05). Conclusiones: Nuestro estudio muestra una alta prevalencia de variaciones estructurales en los adolescentes que practican deporte de alto nivel. No encontramos relación entre practicar un deporte asimétrico y la prevalencia de escoliosis u otra alteración músculo-esquelética

In pre-participative sports medical examinations, the analysis of the anatomical structures that are not directly related to the sport in question, is usually more superficial. A more detailed assessment of the locomotive system may reveal the existence of certain anomalies, which may occasionally go unnoticed. The aim of this study is to describe the prevalence of structural disorders of the locomotive system among elite-level athletes from the Community of Madrid. To establish the relationship between alterations and practising symmetrical or asymmetrical sports. Descriptive cross-sectional study Level of evidence II-III Our study sample includes athletes that are members of the Community of Madrid Sports Technification Plan. 102 athletes, 66 males and 36 females aged between 12 and 19 years. One control group comprises swimming athletes, a sport considered to be symmetrical, and the second group comprises athletes practising sports considered to be asymmetrical: fencing and badminton. The athletes were examined following a blind method by three different specialists using the same protocol. Hypothesis contrasting has been used for qualitative variables, with a 95% confidence level (p<0.05). Ninety-six athletes (94.1%) displayed some kind of structural and/or postural alteration in the pre-participative sports medical examinations. No significant correlation was found (p<0.05) between the different sports on alterations to the spine, knees, extremities and footprint, regardless of whether they were symmetrical or asymmetrical (p<0.05). Conclusions: Our study revealed a high prevalence of structural variation in high-level adolescent athletes. No relationship was found between practising an asymmetrical sport and the prevalence of scoliosis or other muscular-skeletal alterations

The effect of migration on HIV high-risk behaviors among Mexican migrants.

BACKGROUND: Previous studies have shown an association between Mexican migration to the United States and an increased frequency of HIV high-risk behaviors among male Mexican migrants. However, the individual level change in these behaviors after migration has not been quantified. OBJECTIVE: To estimate the change in HIV high-risk behaviors among Mexican migrants after migration to the United States. METHODS: A case-crossover study was embedded in the California-Mexico Epidemiological Surveillance Pilot, a targeted, venue-based, sampling survey. We implemented the study from July to November 2005, studying 458 Mexican migrants at sites in rural and urban areas in Fresno County and San Diego County and directly comparing individual HIV high-risk behaviors before and after migration. RESULTS: After migration, there were increases in the odds of male migrants engaging in sex with a sex worker [odds ratio (OR) = 2.64, P < 0.0001], sex while under the influence of drugs or alcohol (OR = 5.00, P < 0.0001), performing sex work (OR = 6.00, P = 0.070), and sex with a male partner (OR = 13.00, P = 0.001). Those male Mexican migrant subgroups at particularly elevated risk were those in the United States for more than 5 years, those from the youngest age cohort (18-29 years old), or those frequenting high-risk behavior venues and male work venues. CONCLUSIONS: Our results show that Mexican migrant men were significantly more likely to engage in several HIV high-risk behaviors after migration to the United States. However, a smaller proportion of men reported low condom use after migration, indicating increased adoption of some prevention methods. Our results also identified subgroups of Mexican migrants at elevated risk who should be targeted for HIV prevention interventions.

Impact of organic soil amendments on phytochemicals and microbial quality of rocket leaves ( Eruca sativa ).

The effect of soil amendments prepared from organic wastes (sewage sludge and urban solid waste) at two concentrations (45 t ha(-1) as D1 and 135 t ha(-1) as D2) was evaluated on phytochemicals and microbial quality of rocket, a highly valuable vegetable. The addition of sewage sludge to the soil increased rocket yield 5.5 times compared to control and urban solid waste. Organic amendments increased the water content and the maturity stage of the leaves, which contributed to a reduction in the content of total and individual glucosinolates as well as flavonols and anthocyanins. However, higher content of vitamin C was observed after cultivation with sewage sludge at D2 compared to control leaves (204.6 and 177.4 mg 100 g(-1) of fw, respectively). This study shows that sewage sludge at optimum doses can be considered a suitable amendment because of increased crop yield without detrimental effects on phytochemicals, including vitamin C content, when the leaves reached the commercial maturity stage.

Prevalence of sexually transmitted diseases among Latino immigrant day laborers in an urban setting--San Francisco.

BACKGROUND: Although rural Latino migrant laborers have been identified as a group at-risk for acquiring HIV, few studies have examined transmitted diseases (STDs) in urban, Latino migrant laborers. GOAL: To assess the prevalence of STDs in a sample of urban, migrant day laborers in San Francisco. STUDY DESIGN: A convenience sample of participants in the Day Laborer Project of the San Francisco Department of Public Health was screened for STDs from September 1994 to January 2001. Screening included serologic tests for syphilis and nucleic acid amplification tests for gonorrhea and chlamydia. RESULTS: A total of 292 clients participated in the screening program. All participants were male, Latino, and recent immigrants. Of the 235 persons screened for syphilis, secondary syphilis was diagnosed in one (0.4%) participant. Of the 198 persons screened for gonorrhea and chlamydia, 1 (0.5%) had gonorrhea and 7 (3.5%) had chlamydia. CONCLUSION: Urban Latino migrant day laborers are a population at-risk for infection with STDs. Community-based STD screening programs might be an effective way to detect STDs in this population.

Epidemiología de las leucemias infantiles: estudio que abarca 25 años / Epidemiology of infantile leukemias: a 25 year study

El cáncer infantil como causa de mortalidad ha cobrado una importancia creciente en los últimos años, sin que se haya demostrado un incremento de su morbilidad. Tratándose de afecciones malignas, las leucemias registran la mayor incidencia en pediatría. Objetivo. Contribuir al conocimiento de los aspectos epidemiológicos de las leucemias infantiles. Material y método. Se realiza un estudio epidemiológico de los 315 pacientes con diagnóstico de leucemia en el Hospital Pediátrico "José Luis Miranda", en un periodo de 25 años y en las tres provincias centrales del país. Se estudia la morbimortalidad en los diferentes quinquenios. Se determina la incidencia de acuerdo con distintas variables, tales como edad, sexo, tipo morfológico, procedencia, etc. Resultados. La leucemia aguda representa 93.02 por ciento, y la linfoblástica 68.5 por ciento. El grupo de edad más afectado fue el de 1 a 4 años. Se encontró una tasa de morbilidad promedio de 3.05 x 100,000 menores de 15 años. La mortalidad por leucemia disminuyó en estos 25 años en una tasa de 3.6 a 1.25 x 100,000 menores de 15 años. Conclusiones. La mortalidad por leucemia se ha mantenido relativamente estable en el periodo analizado. El pico máximo de incidencia se encontró en el grupo de 1 a 4 años, a expensas de la leucemia linfoide aguda (LLA). No existieron diferencias en la frecuencia de la leucemia entre ambos sexos ni en la zona de procedencia. La mortalidad por leucemia ha disminuido en las tres provincias.