Improved wear performance of ultra high molecular weight polyethylene coated with hydrogenated diamond like carbon

Hydrogenated diamond like carbon (DLCH) thin films were deposited on medical grade ultra high molecular weight polyethylene (UHMWPE) by radio frequency plasma enhanced chemical vapor deposition. The DLCH coating thicknesses ranged from 250 to 700. nm. The substrates were disks made of UHMWPEs typically used for soft components in artificial joints, namely virgin GUR 1050 and highly crosslinked (gamma irradiated in air to 100. kGy) UHMWPEs. Mechanical and tribological properties under bovine serum lubrication at body temperature were assessed on coated and uncoated polyethylenes by means of nano-hardness and ball-on-disk tests, respectively. Morphological features of the worn surfaces were obtained by confocal microscopy and scanning electron microscopy. This study confirms an increase in surface hardness and good wear resistance for coated materials after 24. h of sliding test compared to uncoated polyethylene. These results point out that to coat UHMWPE with DLCH films could be a potential method to reduce backside wear in total hip and knee arthroplasties.Ministerio de Ciencia y Educación MAT2006-12603- C02-01, CSD2008-0002

Identificação de deficiências minerais de bovinos na microrregião Alto Purus-Acre.

A Unidade de Execução de Pesquisa de Âmbito Estadual - UEPAE/Rio Branco, vem desenvolvendo estudos com os objetivos de identificar as deficiências minerais de bovinos na microrregião Alto Purus-Acre, determinando as interrelações entre os níveis de minerais no solo, nas forrageiras e nos tecidos animais durante as estações chuvosa e seca.bitstream/item/145816/1/1097.pd

Music distraction among young drivers: analysis by gender and experience

The aim of this study was to quantify the probability of committing a speed infraction by young drivers and to investigate to what extent listening music could affect young drivers’ emotions as well as their driving performances at the wheel. To achieve this aim, employing Bayesian networks, the study analysed different music styles, in which they resulted in sample drivers’ speed infractions. Gender and drivers’ experiences at the wheel were the other factors, which were taken into account when interpreting the study results. Variables taken into account in this study included type of music whilst driving, gender of drivers, and drivers’ driving experiences. These variables further incorporated into the study of other telemetric variables including acceleration, number of revolutions per minute (RPM) of the engine, brake, traffic, and other types of infractions other than speed, which were considered as dependent variables. A driving simulator was used, and different driving simulation studies were carried out with young people aged between 20 and 28 years. Each participant carried out three simulations by listening to different type of music in each journey. The study defined a conceptual model in which the data were analysed and evaluated mathematically through Bayesian networks. A sensitivity analysis was performed to evaluate the influence of music on driving speed. Based on the different variables, the study further analysed the probability of speed infractions committed by drivers and their adequate speed. The range of frequency probabilities varied between 96.32% (which corresponds to experienced male drivers who do not listen to music) and 79.38% (which corresponds to less-experienced female drivers who listen to music), which resulted in their happiness or aggression.FEDER (Fondo Europeo de Desarrollo Regional) for developing Castilla y Le´on´s region. *e title of the project is “Modelizaci´on mediante t´ecnicas de machine learning de la influencia de las distracciones del conductor en la seguridad vial-Modeling the influence of driver´s distractions on road safety through machine learning techniques.” Ref. BU300P1

Estudio de la tipología de preguntas sobre las temáticas átomo, tabla periódica y enlace químico en las pruebas de acceso a la universidad en Andalucía

Este trabajo analiza las pruebas de acceso a la universidad de química en Andalucía desde las temáticas átomo/tabla periódica (ATP) y enlace químico (EQ), estudiando su frecuencia de aparición y la tipología de preguntas con el sistema de categorías de Smith et al. (definición, algorítmicas y conceptuales). Los resultados muestran que son temáticas poco abordadas (5.4% ATP y 9.4% EQ), a pesar de su importancia en la química escolar. En ningún caso aparecen preguntas de tipo algorítmico y la mayoría son conceptuales en ambas temáticas. Son mayoritarias cuestiones de análisis e interpretación de datos (87%) en el tema ATP, y de explicación de ideas subyacentes y predicción de resultados (85%) y análisis de representación pictórica (76%) en EQ. Sólo el 45% y 13% son cuestiones de definición ATP y EQ, respectivamente

Effect of surface roughness and sterilization on bacterial adherence to ultra-high molecular weight polyethylene

AbstractSterilization with ethylene oxide (EO) and gas plasma (GP) are well-known methods applied to ultra-high molecular weight polyethylene (UHMWPE) surfaces in the belief that they prevent major material changes caused by gamma irradiation. However, the influence of these surface sterilization methods on bacterial adherence to UHMWPE is unknown. UHMWPE samples with various degrees of roughness (0.3, 0.8 and 2.0 µm) were sterilized with either GP or EO. The variations in hydrophobicity, surface free energy and surface functional groups were investigated before and after sterilization. Sterilized samples were incubated with either Staphylococcus aureus or Staphylococcus epidermidis in order to study bacterial adherence to these materials. Fewer bacteria adhered to UHMWPE after sterilization with EO than after sterilization with GP, especially to the smoothest surfaces. No changes in chemical composition of the UHMWPE surface due to sterilization were observed using X-ray photoemission spectroscopy analysis. The decreased bacterial adherence to UHMWPE found at the smoothest surfaces after sterilization with EO was not directly related to changes in chemical composition. Increased bacterial adherence to rougher surfaces was associated with increased polar surface energy of EO-sterilized surfaces

La disfunción familiar como predisponente de la enfermedad mental. ¿Existe tal asociación?

ObjetivosEl objetivo principal es conocer la relación entre la disfunción familiar y la presencia de trastorno mental. El objetivo secundario es conocer la prevalencia y la distribución de los principales tipos de patología mental en la población atendida en atención primaria.Diseño y emplazamientoEstudio descriptivo y transversal realizado en 6 consultas de medicina de familia de un área básica de salud semiurbana.MétodoSe seleccionaron 280 sujetos mediante muestreo aleatorio sistemático de los que acudieron espontáneamente a la consulta. Mediante entrevista se recogieron las variables de estudio: dinámica familiar (medida mediante el test de APGAR familiar), estructura familiar, variables sociodemográficas y presencia de trastorno mental detectado mediante la Mini International Neuropsyquiatric Interview (MINI-DSM IV).ResultadosAceptaron participar 264 sujetos. Un 64,4% era mujer y la media de edad fue de 45,6 años (DE, 16,7). Se detectó patología mental en 87 participantes (33%), siendo la patología más frecuente trastorno de ansiedad generalizada, distimia y depresión mayor. Se encontró alteración de la dinámica familiar en 32 personas (12,3%). No se observaron diferencias significativas en la frecuencia de presentación de patología mental entre el grupo con disfunción familiar y el resto.ConclusionesLos trastornos de salud mental son frecuentes entre los pacientes que acuden a las consultas de atención primaria. No encontramos asociación entre las alteraciones de la dinámica familiar y los trastornos de salud mental, lo que podría deberse a la dificultad para detectar disfunción familiar con el test de APGAR.ObjectivesThe main purpose is to describe the relationship between family disfunction and mental disorder. The secondary objective is to know the prevalence and distribution of mental disorders in primary care attended population.DesignA cross-sectional study was conducted in a primary care setting.Patients and methodsRandom sample was selected over 280 subjects from consultant population. The variables (family function, family structure, social and economic conditions and mental disorders) were collected through interview. APGAR test and Mini International Neuropsychiatric Interview test were performed.Results264 patients were finally included (64% women). Mean age was 45,6 years (SD 16,7). Mental disorders were detected in 87 patients (33%). The most prevalent disorders were generalized anxiety disorder, dysthymia and major depression. family disfunction was found in 32 patients (12,3%). Prevalence of mental disorders wasn't statistically different in the group with family disfunction.ConclusionMental disorders are a common problem between primary care attended population. There wasn't any association between family disfunction and mental disorders, because of the limitations in the APGAR test in detecting family disfunction

Coenzyme Q10 and Cardiovascular Diseases

Coenzyme Q10 (CoQ10), which plays a key role in the electron transport chain by providing an adequate, efficient supply of energy, has another relevant function as an antioxidant, acting in mitochondria, other cell compartments, and plasma lipoproteins. CoQ10 deficiency is present in chronic and age-related diseases. In particular, in cardiovascular diseases (CVDs), there is a reduced bioavailability of CoQ10 since statins, one of the most common lipid-lowering drugs, inhibit the common pathway shared by CoQ10 endogenous biosynthesis and cholesterol biosynthesis. Different clinical trials have analyzed the effect of CoQ10 supplementation as a treatment to ameliorate these deficiencies in the context of CVDs. In this review, we focus on recent advances in CoQ10 supplementation and the clinical implications in the reduction of cardiovascular risk factors (such as lipid and lipoprotein levels, blood pressure, or endothelial function) as well as in a therapeutic approach for the reduction of the clinical complications of CVD