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Lifetime Data (lifetime + data)
Selected AbstractsCharacterization of yeast strains by fluorescence lifetime imaging microscopyFEMS YEAST RESEARCH, Issue 1 2008Hemant Bhatta Abstract The results of fluorescence lifetime imaging microscopy of selected yeast strains were presented and the fact that the lifetime distributions can be successfully used for strain characterization and differentiation was demonstrated. Four strains of industrially relevant yeast Saccharomyces were excited at 405 nm and the autofluorescence observed within 440,540 nm. Using statistical tools such as empirical cumulative distribution functions with Kolmogorov,Smirnov testing, the four studied strains were categorized into three different groups for normal sample size of 70 cells slide,1 at a significance level of 5%. The differentiation of all of the examined strains from one another was shown to be possible by increasing the sample size to 420 cells, which is achievable by taking the lifetime data at six different positions in the slide. [source] The structure of common mental disorders: A replication study in a community sample of adolescents and young adultsINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 4 2009Katja Beesdo-baum Abstract Previous research suggests that patterns of comorbidity of common mental disorders among adults are best reflected by a hierarchical three-factor structure with two correlated factors (,anxious-misery' and ,fear') summarized in a second-order ,internalizing' factor and one ,externalizing' factor. This three-factor structure has not been examined yet in a sample of adolescents and young adults. A representative sample of 3021 adolescents and young adults (baseline age 14,24) were prospectively followed over 10 years. Mental disorders were assessed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) by using the standardized Munich Composite International Diagnostic Interview. Ten mental disorders (major depressive episode, dysthymia, generalized anxiety disorder, social phobia, specific phobia, agoraphobia, panic disorder, alcohol dependence, drug dependence, antisocial personality) were fitted to a series of Confirmatory Factor Analysis models using: (1) 12-month data, and (2) lifetime data from a person-year data set. The three-factor model showed good fit to the observed data in our sample both when 12-month diagnoses and lifetime-to-date diagnoses from a person-year data file were used; yet the higher-order ,internalizing' factor summarizing ,anxious misery' and ,fear' had to be omitted. The three-factor model could be replicated in a sample of adolescents and young adults with the exception that the second-order ,internalizing' factor was not consistent with the data. Further research is necessary to provide more complete insight into the structure of mental disorders by examining the stability of the structure of mental disorders in different developmental stages (ages) and by using a more extensive set of mental disorders. Copyright © 2009 John Wiley & Sons, Ltd. [source] Multi-wavelength fluorescence lifetime spectroscopy: a new approach to the study of endogenous fluorescence in living cells and tissuesLASER PHYSICS LETTERS, Issue 3 2009D. Chorvat Jr. Abstract The study of biological systems in their real environmental conditions is crucial to decipher the true image of structures and processes underlying their functionality. In this regard, development of non-invasive optical techniques that do not require labelling, such as the investigation of tissue endogenous fluorescence, is particularly important and, as reflected in the increasing number of contributions published recently on this subject, was recognized by many leading groups. Multi-spectral and lifetime detection of fluorescence provides an effective experimental tool to discriminate between multiple naturally-occurring fluorophores in living tissues. At the same time, however, data analysis allowing us to understand the spectral, temporal and spatial information gathered, describing individual molecules involved in the autofluorescence of intact biological systems, represents a tough scientific challenge that has not yet been fully resolved. In this review, we discuss the latest advances in technologies that record and assess spectrally-resolved fluorescence lifetime data as well as their biological and clinical applications. We show how these methods provide efficient sensing of molecules correlated with changes in the mitochondrial metabolic redox state in pathological conditions and/or of cell ultrastructures in diseased tissue, based on the presence of oxidation/reductionsensitive fluorophores and/or cell-specific chromophores. Future directions are also outlined. (© 2009 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer and their progeny: a result of nationwide survey in JapanANIMAL SCIENCE JOURNAL, Issue 3 2009Shinya WATANABE ABSTRACT To obtain the data concerning death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer (SCNT) and their progeny produced by Japanese institutions, a nationwide survey was carried out in July-August, 2006. As a result, lifetime data concerning 482 SCNT cattle (97.5% of cattle produced in the country at that time) and 202 progeny of SCNT cattle were accumulated and the death loss of these cattle was analyzed. Although 1/3 of delivered SCNT calves died during the perinatal period due to stillbirth and neonatal death, incidence of death loss due to diseases in SCNT cattle surviving more than 200 days after birth seems to be the same as these in conventionally bred cattle. In contrast, progeny of SCNT cattle showed the same level in death loss as observed in conventionally bred cattle throughout their lifetime. These results suggest that robust health would be expected in SCNT cattle surviving to adulthood and their progeny. [source] Gender Differences in Publication among University Professors in Canada,CANADIAN REVIEW OF SOCIOLOGY/REVUE CANADIENNE DE SOCIOLOGIE, Issue 2 2002M. Reza Nakhaie Cet article analyse un important sondage à l'échelle canadienne et aborde la probématique de la productivité: pourquoi les professeures d'université publient-elles moins que leurs collégues hommes ? Les résultats montrent que, dans l'ensemble, les femmes ont publié moins que les hommes , et ce, de manière significative ,, à la fois durant leur carrière et au cours des trois années qui ont précédé le sondage. Cependant, des analyses multivariables révèlent que des différences s'avèrent plus prononcées dans les données touchant la carrière que dans celles de la courte période. La plus grande différence entre les hommes et les femmes a trait au fait de publier dans une revue à comité de lecture ou sans, et s'applique à toute leur carrière. Enfin, des différences se laissent expliquer par des différences de rang, d'années depuis l'obtention du doctorat, la discipline, le type d'université ainsi que le temps consacré a la recherche. Des problèmes d'évaluation des prédicteurs de la productivité en recherche sont discutés. This paper analyses a large Canadian national survey of professors and tackles the "productivity puzzle" as to why female scientists publish less than male scientists. Results show that, in aggregate, Canadian female professors have published significantly less than their male counterparts, both over their lifetimes and during the three years before the survey. However, multivariate analyses reveal that gender differences in publication are more pronounced in the lifetime data than in the data for the shorter period. Much of the difference in publication between men and women of the academy is in refereed and non-refereed articles and reports over their career. Finally, gender differences in publication are largely accounted for by differences in rank, years since PhD, discipline, type of university and time set aside for research. Problems of assessing predictors of research productivity are discussed. [source] Photoinduced Electron Transfer in ,-Cyclodextrin-Based Supramolecular Dyads: A Free-Energy-Dependence StudyCHEMISTRY - A EUROPEAN JOURNAL, Issue 25 2006Bijitha Balan Abstract Photoinduced electron transfer (PET) between ,-cyclodextrin-appended pyrene (PYCD) and a few acceptor molecules was studied in aqueous solutions. The pyrene moiety in PYCD is located above the narrower rim of the ,-CD and is fully exposed to water. The acceptors are monocyclic organic molecules and, upon dissolution in water in the presence of PYCD, a fraction of the donor,acceptor systems is present as supramolecular dyads and the remaining fraction as free molecules. Free-energy-dependence studies showed that electron transfer in the supramolecular dyads follows the Marcus equation. The donor,acceptor coupling and the reorganization energy were determined from fits of the data to the Marcus equation. The electronic coupling was found to be similar to those reported for hydrogen-bonded systems. It appears that the actual ,out values are somewhat lower than values calculated with the continuum model. The experimental design has also allowed, for the first time, a visual demonstration of the inverted region on the basis of the raw fluorescence lifetime data. [source] | ||||||||||