Radiolytic mapping of solvent-contact surfaces in photosystem II of higher plants: Experimental identification of putative water channels within the photosystem

Background: Substrate water must reach the buried Mn4O 5Ca cluster in Photosystem II. Results: OH produced by radiolysis modified buried amino acid residues. These were mapped onto the PS II crystal structure. Conclusion: Two groups of oxidized residues were identified which form putative pathways to the Mn4O5Ca cluster. Significance: Identification of water and oxygen channels is crucial for our understanding of Photosystem II function. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc

Simple replication methods for producing nanoslits in thermoplastics and the transport dynamics of double-stranded DNA through these slits

Mixed-scale nano-and microfluidic networks were fabricated in thermoplastics using simple and robust methods that did not require the use of sophisticated equipment to produce the nanostructures. High-precision micromilling (HPMM) and photolithography were used to generate mixed-scale molding tools that were subsequently used for producing fluidic networks into thermoplastics such as poly(methyl methacrylate), PMMA, cyclic olefin copolymer, COC, and polycarbonate, PC. Nanoslit arrays were imprinted into the polymer using a nanoimprinting tool, which was composed of an optical mask with patterns that were 2-7 mu m in width and a depth defined by the Cr layer (100 nm), which was deposited onto glass. The device also contained a microchannel network that was hot embossed into the polymer substrate using a metal molding tool prepared via HPMM. The mixed-scale device could also be used as a master to produce a polymer stamp, which was made from polydimethylsiloxane, PDMS, and used to generate the mixed-scale fluidic network in a single step. Thermal fusion bonding of the cover plate to the substrate at a temperature below their respective T(g) was accomplished by oxygen plasma treatment of both the substrate and cover plate, which significantly reduced thermally induced structural deformation during assembly: similar to 6% for PMMA and similar to 9% for COC nanoslits. The electrokinetic transport properties of double-stranded DNA (dsDNA) through the polymeric nanoslits (PMMA and COC) were carried out. In these polymer devices, the dsDNA demonstrated a field-dependent electrophoretic mobility with intermittent transport dynamics. DNA mobilities were found to be 8.2 +/- 0.7 x 10(-4) cm(2) V(-1) s(-1) and 7.6 +/- 0.6 x 10(-4) cm(2) V(-1) s(-1) for PMMA and COC, respectively, at a field strength of 25 V cm(-1). The extension factors for lambda-DNA were 0.46 in PMMA and 0.53 in COC for the nanoslits (2-6% standard deviation).close171

Fully Integrated Thermoplastic Genosensor for the Highly Sensitive Detection and Identification of Multi-Drug-Resistant Tuberculosis

A modular system for the reporting of drug-resistant strains of Mycobacterium tuberculosis (Mtb) in less than 30 min with full process automation was developed (see picture; MDR-TB=multi-drug resistance tuberculosis). The fluidic cartridge uses a polymerchain reaction (PCR)/ligase detection reaction (LDR)/universal array assay that can detect, with high reliability, resistant strains that are a minority (less than 1 %) from a mixed population

QUALIDADE DE VIDA RELACIONADA À SAÚDE (HRQL) DE ADULTOS ENTRE 50 E 80 ANOS PRATICANTES DE ATIVIDADE FÍSICA REGULAR: APLICAÇÃO DO SF-36

A qualidade de vida relacionada à saúde-HRQL possui um caráter multidimensional com integração da saúde física, do bem-estar psicológico e da satisfação social. O objetivo foi avaliar a qualidade de vida relacionada à saúde (HRQL) de participantes de meia-idade e de idosos de um projeto de atividade física regular. O tipo de estudo foi descritivo, com corte transversal, sendo que a amostra foi composta por 40 adultos com idade entre 50 e 80 anos, integrantes do CELARI da ESEF/UFRGS. O instrumento utilizado foi o SF-36 e a análise empregada utilizou a estatística descritiva e o teste de correlação de Pearson. A pontuação dos domínios por ordem decrescente foi: AS, AF, AE, EGS, CF, SM, VIT, DOR. Houve correlação positiva significativa entre a maioria dos domínios do SF-36. As correlações não significativas ocorreram entre EGS x AS, SM x AF. A idade apenas correlacionou-se com o domínio EGS. A HRQL da amostra mostrou-se com valores superiores, ao ser comparada com a de outros estudos. Os valores atingiram no mínimo 70% de pontuação, na média dos domínios. Os resultados indicaram um nível satisfatório de HRQL e relação entre os domínios do SF-36. palavras-chave Envelhecimento. Qualidade de Vida. Atividade Física. Saúde. abstract The health-related quality of life – HRQOL is a multidimensional issue with integration of physical health, psychological well-being and social satisfaction factors. The aim of this study was to evaluate the health-related quality of life – HRQOL in ageing people who practice regular physical activity. This study was a descriptive cross-sectional and  the sample included 40 adults, aged between 50 and 80 years, attending a University Extension Program. The instrument used was the Brazilian version of Short Form-36. Descriptive statistical analysis was used to summarize HRQL data and Pearson’s correlation for comparison between domains. The score of the domains in descending order were: AS, AF, AE, EGS, CF, SM, VIT, DOR. There was a significant positive correlation between the majority of SF-36. The correlations were not significant between EGS x AS, SM x AF. The age was correlated only with the EGS field. The HRQL of the sample proved to be higher, when compared with other studies. The values ​​reached a minimum score of 70% in average scores. The results indicated a satisfactory level of HRQOL and a significant relationship between different aspects of health-related quality of life. keywords Aging. Quality of Life. Physical Activity. Health

Direct fabrication of deep x-ray lithography masks by micromechanical milling

Micromechanical milling has been shown to be a rapid and direct method for fabricating masks for deep x-ray lithography with lateral absorber features down to 10 micrometers. Conventional x-ray mask fabrication requires complex processes and equipment, and a faster and simpler method using micromechanical milling was investigated for larger microstructures for mesoscale applications. Micromilled x-ray masks consisting of a layered architecture of gold and titanium films on graphite yielded exposures in PMMA with accuracy and repeatability suitable for prototype purposes. A method for compensating milling tool radial runout was adapted, and the average accuracy of mask absorber features was 0.65 micrometers, with an average standard deviation of 0.55 micrometers. The milling process leaves some absorber burrs, and the absorber wall is tapered, which introduces an additional process bias. Mask fabrication by micromilling is fast and, therefore, less costly than conventional mask fabrication processes. © 1998 Elsevier Science Inc

Metrology and quantification of micromilled X-ray masks and exposures

© 1994 SPIE. Micromechanical milling has been shown to be a rapid and direct method for the production of X-ray masks with features within the process limits. A method for compensating milling tool run out has been adapted and the tolerance of mask absorber features has been reduced to approximately 0.5 micrometers. The milling process leaves some absorber burrs and the absorber is also tapered at the machined wall which introduces an additional process bias, both of which add to exposure degradation. Nevertheless, both of these effects can be greatly reduced with further work