Presence of fast quenching mechanisms in Al2O3:Er3+

The measurement of luminescence decay curves and non-saturable absorption in erbium-doped aluminum oxide waveguides reveals the presence of fast quenching effects, leading to a revised value of the microscopic and macroscopic parameters of energy-transfer upconversion

Body composition in early childhood : Parental, fetal, postnata and genetic determinants of fat, lean and bone mass. The Generation R Study

Th e prevalence of childhood overweight and obesity has increased dramatically in developed countries over the past two decades. Childhood obesity is associated with short-term morbidity such as asthma and psychological problems and with an increased risk for chronic morbidity and mortality in adulthood. Previous studies have shown that both parental anthropometrics and anthropometrics at birth are associated with obesity in childhood. Birth weight is strongly associated with perinatal morbidity and mortality. Low birth weight is related to impaired growth and development, and increased mortality in infancy. High birth weight is related to complications during delivery (such as shoulder dystocia and caesarean sections) and to obesity during child- and adulthood. Low birth weight seems also to be associated with diseases in adulthood such as obesity in later life. Determinants of adult disease have been suggested to be: parental anthropometrics, fetal growth and genetics. Until now birth weight was used as a proxy for fetal growth. Although birth weight is the result of fetal growth during pregnancy, diff erent fetal growth patterns may lead to diff erent health consequences

Identifying statistical dependence in genomic sequences via mutual information estimates

Questions of understanding and quantifying the representation and amount of information in organisms have become a central part of biological research, as they potentially hold the key to fundamental advances. In this paper, we demonstrate the use of information-theoretic tools for the task of identifying segments of biomolecules (DNA or RNA) that are statistically correlated. We develop a precise and reliable methodology, based on the notion of mutual information, for finding and extracting statistical as well as structural dependencies. A simple threshold function is defined, and its use in quantifying the level of significance of dependencies between biological segments is explored. These tools are used in two specific applications. First, for the identification of correlations between different parts of the maize zmSRp32 gene. There, we find significant dependencies between the 5' untranslated region in zmSRp32 and its alternatively spliced exons. This observation may indicate the presence of as-yet unknown alternative splicing mechanisms or structural scaffolds. Second, using data from the FBI's Combined DNA Index System (CODIS), we demonstrate that our approach is particularly well suited for the problem of discovering short tandem repeats, an application of importance in genetic profiling.Comment: Preliminary version. Final version in EURASIP Journal on Bioinformatics and Systems Biology. See http://www.hindawi.com/journals/bsb

Widely wavelength-selective Al2O3:Er3+ ring laser

Integrated Al2O3:Er3+ channel waveguide ring lasers were realized on thermally oxidized silicon substrates. High pump power coupling into- and low output power coupling from the ring is achieved in a straightforward design. Wavelength\ud selection in the range 1532 to 1557 nm was demonstrated by\ud varying the length of the output coupler from the ring

Ultimate behavior of idealized composite floor elements at ambient and elevated temperature

This paper is concerned with the ultimate behavior of composite floor slabs under extreme loading situations resembling those occurring during severe building fires. The study focuses on the failure state associated with rupture of the reinforcement in idealized slab elements, which become lightly reinforced in a fire situation due to the early loss of the steel deck. The paper describes a fundamental approach for assessing the failure limit associated with reinforcement fracture in lightly reinforced beams, representing idealized slab strips. A description of the ambient-temperature tests on isolated restrained elements, carried out to assess the influence of key material parameters on the failure conditions, is firstly presented. The results of a series of material tests, undertaken mainly to examine the effect of elevated temperature on ductility, are also described. A simplified analytical model is employed, in conjunction with the experimental findings, to assess the salient material parameters and their implications on the ultimate response at both ambient and elevated temperature. © 2009 Springer Science+Business Media, LLC