3,390 research outputs found
The role of the nature of the noise in the thermal conductance of mechanical systems
Focussing on a paradigmatic small system consisting of two coupled damped
oscillators, we survey the role of the L\'evy-It\^o nature of the noise in the
thermal conductance. For white noises, we prove that the L\'evy-It\^o
composition (Lebesgue measure) of the noise is irrelevant for the thermal
conductance of a non-equilibrium linearly coupled chain, which signals the
independence between mechanical and thermodynamical properties. On the other
hand, for the non-linearly coupled case, the two types of properties mix and
the explicit definition of the noise plays a central role.Comment: 9 pages, 2 figures. To be published in Physical Review
Complete genome sequences of clinical Pandoraea fibrosis isolates
Pandoraea fibrosis is a newly identified Gram-negative bacterial species that was isolated from the respiratory tract of an Australian cystic fibrosis patient. The complete assembled genome sequences of two consecutive isolates (second isolate collected 11 months after antibiotic treatment) from the same individual are presented here
Testing and Assessment in an International Context: Cross- and Multi-cultural Issues
Globalisation, increase of migration flows, and the concurrent worldwide competitiveness impose rethinking of testing and assessment procedures and practices in an international and multicultural context. This chapter reviews the methodological and practical implications for psychological assessment in the field of career guidance. The methodological implications are numerous and several aspects have to be considered, such as cross-cultural equivalence or construct, method, and item bias. Moreover, the construct of culture by itself is difficult to define and difficult to measure. In order to provide non-discriminatory assessment, counsellors should develop their clinical cross-cultural competencies, develop more specific intervention strategies, and respect cultural differences. Several suggestions are given concerning translation and adaptation of psychological instruments, developing culture specific measures, and the use of these instruments. More research in this field should use mixed methods, multi-centric designs, and consider emic and etic psychological variables. A multidisciplinary approach might also allow identifying culture specific and ecological meaningful constructs. Non-discriminatory assessment implies considering the influence and interaction of personal characteristics and environmental factors
Supercritical fluid technology as a tool to prepare gradient multifunctional architectures towards regeneration of osteochondral injuries
Platelet lysates (PLs) are a natural source of growth factors (GFs) known for its stimulatory role on stem cells which can be obtained after activation of platelets from blood plasma. The possibility to use PLs as growth factor source for tissue healing and regeneration has been pursued following different strategies. Platelet lysates are an enriched pool of growth factors which can be used as either a GFs source or as a three-dimensional (3D) hydrogel. However, most of current PLs-based hydrogels lack stability, exhibiting significant shrinking behavior. This chapter focuses on the application of supercritical fluid technology to develop three-dimensional architectures of PL constructs, crosslinked with genipin. The proposed technology allows in a single step operation the development of mechanically stable porous structures, through chemical crosslinking of the growth factors present in the PL pool, followed by supercritical drying of the samples. Furthermore gradient structures of PL-based structures with bioactive glass are also presented and are described as an interesting approach to the treatment of osteochondral defects.info:eu-repo/semantics/publishedVersio
CEM03 and LAQGSM03 - new modeling tools for nuclear applications
An improved version of the Cascade-Exciton Model (CEM) of nuclear reactions
realized in the code CEM2k and the Los Alamos version of the Quark-Gluon String
Model (LAQGSM) have been developed recently at LANL to describe reactions
induced by particles and nuclei for a number of applications. Our CEM2k and
LAQGSM merged with the GEM2 evaporation/fission code by Furihata have
predictive powers comparable to other modern codes and describe many reactions
better than other codes; therefore both our codes can be used as reliable event
generators in transport codes for applications. During the last year, we have
made a significant improvements to the intranuclear cascade parts of CEM2k and
LAQGSM, and have extended LAQGSM to describe photonuclear reactions at energies
to 10 GeV and higher. We have produced in this way improved versions of our
codes, CEM03.01 and LAQGSM03.01. We present a brief description of our codes
and show illustrative results obtained with CEM03.01 and LAQGSM03.01 for
different reactions compared with predictions by other models, as well as
examples of using our codes as modeling tools for nuclear applications.Comment: 12 pages, 10 figures, to be published in Journal of Physics:
Conference Series: Proc. Europhysics Conf. on New Trends in Nuclear Physics
Applications and Technologies (NPDC19), Pavia, Italy, September 5-9, 200
Intraspecific Variation of the Aquatic Fungus Articulospora tetracladia: An Ubiquitous Perspective
The worldwide-distributed aquatic fungus Articulospora tetracladia Ingold is a dominant sporulating species in streams of the Northwest Iberian Peninsula. To elucidate the genetic diversity of A. tetracladia, we analyzed isolates collected from various types of plant litter or foam in streams from North and Central Portugal and North Spain, between 2000 and 2010. Genetic diversity of these fungal populations was assessed by denaturing gradient gel electrophoresis (DGGE) fingerprints and by using ITS1-5.8S-ITS2 barcodes. Moreover, ITS1-5.8S-ITS2 barcodes of A. tetracladia reported in other parts of the world (Central Europe, United Kingdom, Canada, Japan and Malaysia) were retrieved from the National Center for Biotechnology (NCBI) and the National Institute of Technology and Evaluation Biological Resource Center (NBRC) to probe into genetic diversity of A. tetracladia. PCR-DGGE of ITS2 region of 50 Iberian fungal isolates distinguished eight operational taxonomic units (OTUs), which were similar to those obtained from neighboring trees based on ITS2 gene sequences. On the other hand, ITS1-5.8S-ITS2 barcodes of 68 fungal isolates yielded nine OTUs, but five fungal isolates were not assigned to any of these OTUs. Molecular diversity was highest for OTU-8, which included only European isolates. Two haplotypes were observed within OTU-8 and OTU-9, while only one haplotype was found within each of the remaining OTUs. Malaysia did not share haplotypes with other countries. Overall results indicate that, apart from the Malaysian genotypes, A. tetracladia genotypes were geographically widespread irrespective of sampling time, sites or substrates. Furthermore, PCR-DGGE appeared to be a rapid tool for assessing intraspecific diversity of aquatic hyphomycetes
Knowledge-based analysis of microarrays for the discovery of transcriptional regulation relationships
<p>Abstract</p> <p>Background</p> <p>The large amount of high-throughput genomic data has facilitated the discovery of the regulatory relationships between transcription factors and their target genes. While early methods for discovery of transcriptional regulation relationships from microarray data often focused on the high-throughput experimental data alone, more recent approaches have explored the integration of external knowledge bases of gene interactions.</p> <p>Results</p> <p>In this work, we develop an algorithm that provides improved performance in the prediction of transcriptional regulatory relationships by supplementing the analysis of microarray data with a new method of integrating information from an existing knowledge base. Using a well-known dataset of yeast microarrays and the Yeast Proteome Database, a comprehensive collection of known information of yeast genes, we show that knowledge-based predictions demonstrate better sensitivity and specificity in inferring new transcriptional interactions than predictions from microarray data alone. We also show that comprehensive, direct and high-quality knowledge bases provide better prediction performance. Comparison of our results with ChIP-chip data and growth fitness data suggests that our predicted genome-wide regulatory pairs in yeast are reasonable candidates for follow-up biological verification.</p> <p>Conclusion</p> <p>High quality, comprehensive, and direct knowledge bases, when combined with appropriate bioinformatic algorithms, can significantly improve the discovery of gene regulatory relationships from high throughput gene expression data.</p
Dynamical Boson Stars
The idea of stable, localized bundles of energy has strong appeal as a model
for particles. In the 1950s John Wheeler envisioned such bundles as smooth
configurations of electromagnetic energy that he called {\em geons}, but none
were found. Instead, particle-like solutions were found in the late 1960s with
the addition of a scalar field, and these were given the name {\em boson
stars}. Since then, boson stars find use in a wide variety of models as sources
of dark matter, as black hole mimickers, in simple models of binary systems,
and as a tool in finding black holes in higher dimensions with only a single
killing vector. We discuss important varieties of boson stars, their dynamic
properties, and some of their uses, concentrating on recent efforts.Comment: 79 pages, 25 figures, invited review for Living Reviews in
Relativity; major revision in 201
- …