Showing papers by "University of Ljubljana published in 2008"
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TL;DR: A novel method for detecting and localizing objects of a visual category in cluttered real-world scenes that is applicable to a range of different object categories, including both rigid and articulated objects and able to achieve competitive object detection performance from training sets that are between one and two orders of magnitude smaller than those used in comparable systems.
Abstract: This paper presents a novel method for detecting and localizing objects of a visual category in cluttered real-world scenes. Our approach considers object categorization and figure-ground segmentation as two interleaved processes that closely collaborate towards a common goal. As shown in our work, the tight coupling between those two processes allows them to benefit from each other and improve the combined performance.
The core part of our approach is a highly flexible learned representation for object shape that can combine the information observed on different training examples in a probabilistic extension of the Generalized Hough Transform. The resulting approach can detect categorical objects in novel images and automatically infer a probabilistic segmentation from the recognition result. This segmentation is then in turn used to again improve recognition by allowing the system to focus its efforts on object pixels and to discard misleading influences from the background. Moreover, the information from where in the image a hypothesis draws its support is employed in an MDL based hypothesis verification stage to resolve ambiguities between overlapping hypotheses and factor out the effects of partial occlusion.
An extensive evaluation on several large data sets shows that the proposed system is applicable to a range of different object categories, including both rigid and articulated objects. In addition, its flexible representation allows it to achieve competitive object detection performance already from training sets that are between one and two orders of magnitude smaller than those used in comparable systems.
1,084 citations
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TL;DR: In this article, the authors conducted a meta-analysis of 45 published and unpublished experimental comparisons between web and other survey modes and found that on average, web surveys yield an 11% lower response rate compared to other modes (the 95% confidence interval is confined by 15% and 6% to the disadvantage of the web mode).
Abstract: One question that arises when discussing the usefulness of web-based surveys is whether they gain the same response rates compared to other modes of collecting survey data. A common perception exists that, in general, web survey response rates are considerably lower. However, such unsystematic anecdotal evidence could be misleading and does not provide any useful quantitative estimate. Metaanalytic procedures synthesising controlled experimental mode comparisons could give accurate answers but, to the best of the authors' knowledge, such research syntheses have so far not been conducted. To overcome this gap, the authors have conducted a meta-analysis of 45 published and unpublished experimental comparisons between web and other survey modes. On average, web surveys yield an 11% lower response rate compared to other modes (the 95% confidence interval is confined by 15% and 6% to the disadvantage of the web mode). This response rate difference to the disadvantage of the web mode is systematically influenced by the sample recruitment base (a smaller difference for panel members as compared to one-time respondents), the solicitation mode chosen for web surveys (a greater difference for postal mail solicitation compared to email) and the number of contacts (the more contacts, the larger the difference in response rates between modes). No significant influence on response rate differences can be revealed for the type of mode web surveys are compared to, the type of target population, the type of sponsorship, whether or not incentives were offered, and the year the studies were conducted. Practical implications are discussed.
942 citations
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TL;DR: In this article, the authors derived new constraints on the mass of the Milky Way's dark matter halo, based on 2401 rigorously selected blue horizontal-branch halo stars from SDSS DR6.
Abstract: We derive new constraints on the mass of the Milky Way's dark matter halo, based on 2401 rigorously selected blue horizontal-branch halo stars from SDSS DR6. This sample enables construction of the full line-of-sight velocity distribution at different galactocentric radii. To interpret these distributions, we compare them to matched mock observations drawn from two different cosmological galaxy formation simulations designed to resemble the Milky Way. This procedure results in an estimate of the Milky Way's circular velocity curve to ~60 kpc, which is found to be slightly falling from the adopted value of 220 km s?1 at the Sun's location, and implies -->M( Vcir(r) , derived in statistically independent bins, is found to be consistent with the expectations from an NFW dark matter halo with the established stellar mass components at its center. If we assume that an NFW halo profile of characteristic concentration holds, we can use the observations to estimate the virial mass of the Milky Way's dark matter halo, -->Mvir = 1.0+ 0.3?0.2 ? 1012 M?, which is lower than many previous estimates. We have checked that the particulars of the cosmological simulations are unlikely to introduce systematics larger than the statistical uncertainties. This estimate implies that nearly 40% of the baryons within the virial radius of the Milky Way's dark matter halo reside in the stellar components of our Galaxy. A value for -->Mvir of only ~ -->1 ? 1012 M? also (re)opens the question of whether all of the Milky Way's satellite galaxies are on bound orbits.
789 citations
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TL;DR: The extent and role of the research area of predictive data mining and a framework to cope with the problems of constructing, assessing and exploiting data mining models in clinical medicine are discussed and proposed.
753 citations
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TL;DR: In this paper, the authors numerically investigate Heisenberg $XXZ$ spin-$1∕2$ chain in a spatially random static magnetic field and show that for large enough random fields, infinite temperature spin-spin correlation function displays exponential localization in space indicating insulating behavior of the model.
Abstract: We numerically investigate Heisenberg $XXZ$ spin-$1∕2$ chain in a spatially random static magnetic field. We find that time-dependent density-matrix renormalization group simulations of time evolution can be performed efficiently, namely, the dimension of matrices needed to efficiently represent the time evolution increases linearly with time and entanglement entropies for typical chain bipartitions increase logarithmically. As a result, we show that for large enough random fields, infinite temperature spin-spin correlation function displays exponential localization in space indicating insulating behavior of the model.
704 citations
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University of Washington1, Institute for Advanced Study2, Princeton University3, University of California, Santa Cruz4, Fermilab5, Rensselaer Polytechnic Institute6, Joint Institute for Nuclear Astrophysics7, University of Texas at Austin8, Texas Tech University9, Australian National University10, Max Planck Society11, University of Ljubljana12, Lawrence Berkeley National Laboratory13, Johns Hopkins University14, Harvard University15, Austin Peay State University16, University of Tokyo17, Apache Corporation18, Pennsylvania State University19, University of Chicago20
TL;DR: In this article, a polynomial model for estimating the metallicity and rotational velocity distributions of SDSS spectra was proposed, which is similar to random and systematic uncertainties in spectroscopic determinations.
Abstract: In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is producing a massive spectroscopic database which already contains over 280,000 stellar spectra. Using eectiv e temperature and metallicity derived from SDSS spectra for 60,000 F and G type main sequence stars (0:2 < g r < 0:6), we develop polynomial models, reminiscent of traditional methods based on the UBV photometry, for estimating these parameters from the SDSS u g and g r colors. These estimators reproduce SDSS spectroscopic parameters with a root-mean-square scatter of 100 K for eectiv e temperature, and 0.2 dex for metallicity (limited by photometric errors), which are similar to random and systematic uncertainties in spectroscopic determinations. We apply this method to a photometric catalog of coadded SDSS observations and study the photometric metallicity distribution of 200,000 F and G type stars observed in 300 deg 2 of high Galactic latitude sky. These deeper (g < 20:5) and photometrically precise ( 0.01 mag) coadded data enable an accurate measurement of the unbiased metallicity distribution for a complete volume-limited sample of stars at distances between 500 pc and 8 kpc. The metallicity distribution can be exquisitely modeled using two components with a spatially varying number ratio, that correspond to disk and halo. The best-t number ratio of the two components is consistent with that implied by the decomposition of stellar counts proles into exponential disk and power-law halo components by Juri c et al. (2008). The two components also possess the kinematics expected for disk and halo stars. The metallicity of the halo component can be modeled as a spatially invariant Gaussian distribution with a mean of [F e=H] = 1:46 and a standard deviation of 0.3 dex. The disk metallicity distribution is non-Gaussian, with a remarkably small scatter (rms 0.16 dex) and the median smoothly decreasing with distance from the plane from 0:6 at 500 pc to 0:8 beyond several kpc. Similarly, we nd using proper motion measurements that a nonGaussian rotational velocity distribution of disk stars shifts by 50 km/s as the distance from the plane increases from 500 pc to several kpc. Despite this similarity, the metallicity and rotational velocity distributions of disk stars are not correlated (Kendall’s = 0:017 0:018). This absence of a correlation between metallicity and kinematics for disk stars is in a conict with the traditional decomposition in terms of thin and thick disks, which predicts a strong correlation ( = 0:30 0:04) at 1 kpc from the mid-plane. Instead, the variation of the metallicity and rotational velocity distributions can be modeled using non-Gaussian functions that retain their shapes and only shift as the distance from the mid-plane increases. We also study the metallicity distribution using a shallower (g < 19:5) but much larger sample of close to three million stars in 8500 sq. deg. of sky included in SDSS Data Release 6. The large sky coverage enables the detection of coherent substructures in the kinematics{ metallicity space, such as the Monoceros stream, which rotates faster than the LSR, and has a median metallicity of [F e=H] = 0:95, with an rms scatter of only 0.15 dex. We extrapolate our results to the performance expected from the Large Synoptic Survey Telescope (LSST) and estimate that LSST will obtain metallicity measurements accurate to 0.2 dex or better, with proper motion measurements accurate to 0.2-0.5 mas/yr, for about 200 million F/G dwarf stars within a distance limit of 100 kpc (g < 23:5). Subject headings: methods: data analysis | stars: statistics | Galaxy: halo, kinematics and dynamics, stellar content, structure
649 citations
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Rega Institute for Medical Research1, Merck & Co.2, International Centre for Diarrhoeal Disease Research, Bangladesh3, Katholieke Universiteit Leuven4, Hungarian Academy of Sciences5, Baylor College of Medicine6, National Center for Immunization and Respiratory Diseases7, Health Protection Agency8, University of Bari9, Nagasaki University10, National Institutes of Health11, Istituto Superiore di Sanità12, Ohio Agricultural Research and Development Center13, Federal University of Rio de Janeiro14, University of Ljubljana15, Fujita Health University16, University of Cambridge17
TL;DR: A Rotavirus Classification Working Group (RCWG) including specialists in molecular virology, infectious diseases, epidemiology, and public health was formed, which can assist in the appropriate delineation of new genotypes, thus avoiding duplications and helping minimize errors.
Abstract: Recently, a classification system was proposed for rotaviruses in which all the 11 genomic RNA segments are used (Matthijnssens et al. in J Virol 82:3204–3219, 2008). Based on nucleotide identity cut-off percentages, different genotypes were defined for each genome segment. A nomenclature for the comparison of complete rotavirus genomes was considered in which the notations Gx-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-Tx-Ex-Hx are used for the VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5/6 encoding genes, respectively. This classification system is an extension of the previously applied genotype-based system which made use of the rotavirus gene segments encoding VP4, VP7, VP6, and NSP4. In order to assign rotavirus strains to one of the established genotypes or a new genotype, a standard procedure is proposed in this report. As more human and animal rotavirus genomes will be completely sequenced, new genotypes for each of the 11 gene segments may be identified. A Rotavirus Classification Working Group (RCWG) including specialists in molecular virology, infectious diseases, epidemiology, and public health was formed, which can assist in the appropriate delineation of new genotypes, thus avoiding duplications and helping minimize errors. Scientists discovering a potentially new rotavirus genotype for any of the 11 gene segments are invited to send the novel sequence to the RCWG, where the sequence will be analyzed, and a new nomenclature will be advised as appropriate. The RCWG will update the list of classified strains regularly and make this accessible on a website. Close collaboration with the Study Group Reoviridae of the International Committee on the Taxonomy of Viruses will be maintained.
636 citations
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TL;DR: This review deals with the cytoplasmic steps of peptidoglycan biosynthesis and the chemical and enzymatic synthesis of the nucleotide precursor substrates that are not commercially available and the search for specific inhibitors that could act as antibacterial compounds.
Abstract: The biosynthesis of bacterial cell wall peptidoglycan is a complex process that involves enzyme reactions that take place in the cytoplasm (synthesis of the nucleotide precursors) and on the inner side (synthesis of lipid-linked intermediates) and outer side (polymerization reactions) of the cytoplasmic membrane. This review deals with the cytoplasmic steps of peptidoglycan biosynthesis, which can be divided into four sets of reactions that lead to the syntheses of (1) UDP-N-acetylglucosamine from fructose 6-phosphate, (2) UDP-N-acetylmuramic acid from UDP-N-acetylglucosamine, (3) UDP-N-acetylmuramyl-pentapeptide from UDP-N-acetylmuramic acid and (4) D-glutamic acid and dipeptide D-alanyl-D-alanine. Recent data concerning the different enzymes involved are presented. Moreover, special attention is given to (1) the chemical and enzymatic synthesis of the nucleotide precursor substrates that are not commercially available and (2) the search for specific inhibitors that could act as antibacterial compounds.
620 citations
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Joint Institute for Nuclear Astrophysics1, University of Texas at Austin2, Texas Tech University3, University of Ljubljana4, Max Planck Society5, Australian National University6, University of California, Santa Cruz7, Fermilab8, Rensselaer Polytechnic Institute9, Harvard University10, Chinese Academy of Sciences11
TL;DR: The Sloan Extension for Galactic Exploration and Understanding (SEGUE) Stellar Parameter Pipeline (SSPP) as discussed by the authors is a stellar atmospheric parameters pipeline for AFGK-type stars.
Abstract: We describe the development and implementation of the Sloan Extension for Galactic Exploration and Understanding (SEGUE) Stellar Parameter Pipeline (SSPP) The SSPP is derived, using multiple techniques, radial velocities, and the fundamental stellar atmospheric parameters (effective temperature, surface gravity, and metallicity) for AFGK-type stars, based on medium-resolution spectroscopy and ugriz photometry obtained during the course of the original Sloan Digital Sky Survey (SDSS-I) and its Galactic extension (SDSS-II/SEGUE) The SSPP also provides spectral classification for a much wider range of stars, including stars with temperatures outside the window where atmospheric parameters can be estimated with the current approaches This is Paper I in a series of papers on the SSPP; it provides an overview of the SSPP, and tests of its performance using several external data sets Random and systematic errors are critically examined for the current version of the SSPP, which has been used for the sixth public data release of the SDSS (DR-6)
570 citations
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TL;DR: In this article, the effect of strategic choices, market orientation, and company size on two distinct dimensions of strategic management accounting (SMA) and, in turn, the mediating effect of SMA on company performance was examined.
Abstract: This study examines the effect of strategic choices, market orientation, and company size on two distinct dimensions of strategic management accounting (SMA) and, in turn, the mediating effect of SMA on company performance. A model is advanced and tested using structural equation modelling and data collected from a sample of 193 large Slovenian companies. The validity of the quantitative data findings has been appraised using qualitative data collected in ten exploratory interviews. The study’s findings support contingency theory’s tenet of no universally appropriate SMA system, with factors such as company size and strategy having a significant bearing on the successful application of SMA. 2008 Elsevier Ltd. All rights reserved.
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Pennsylvania State University1, Special Astrophysical Observatory2, University of Hertfordshire3, Purple Mountain Observatory4, Brera Astronomical Observatory5, University College London6, Liverpool John Moores University7, Goddard Space Flight Center8, University of Leicester9, University of Warsaw10, University of Nevada, Las Vegas11, Universities Space Research Association12, University of Milan13, University of Amsterdam14, Marshall Space Flight Center15, Hebrew University of Jerusalem16, University of Bologna17, Spanish National Research Council18, European Southern Observatory19, Space Telescope Science Institute20, ASTRON21, Leiden University22, Swinburne University of Technology23, University of Ljubljana24, Warsaw University of Technology25, INAF26, University of Warwick27, Aryabhatta Research Institute of Observational Sciences28, Joint Institute for VLBI in Europe29, University of California, Santa Cruz30, University of Perugia31
TL;DR: Observations of the extraordinarily bright prompt optical and γ-ray emission of GRB 080319B that provide diagnostics within seconds of its formation, followed by broadband observations of the afterglow decay that continued for weeks.
Abstract: Long-duration gamma-ray bursts (GRBs) release copious amounts of energy across the entire electromagnetic spectrum, and so provide a window into the process of black hole formation from the collapse of massive stars Previous early optical observations of even the most exceptional GRBs (990123 and 030329) lacked both the temporal resolution to probe the optical flash in detail and the accuracy needed to trace the transition from the prompt emission within the outflow to external shocks caused by interaction with the progenitor environment Here we report observations of the extraordinarily bright prompt optical and gamma-ray emission of GRB 080319B that provide diagnostics within seconds of its formation, followed by broadband observations of the afterglow decay that continued for weeks We show that the prompt emission stems from a single physical region, implying an extremely relativistic outflow that propagates within the narrow inner core of a two-component jet
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TL;DR: In this paper, the periods of cambial activity and cell differentiation were assessed on a weekly time-scale on histological sections of Cambium and wood tissue collected over 2 to 5 years per site from 1998 to 2005 from the stems of seven conifer species.
Abstract: Aim To identify temperatures at which cell division and differentiation are active in order to verify the existence of a common critical temperature determining growth in conifers of cold climates.
Location Ten European and Canadian sites at different latitudes and altitudes.
Methods The periods of cambial activity and cell differentiation were assessed on a weekly time-scale on histological sections of cambium and wood tissue collected over 2 to 5 years per site from 1998 to 2005 from the stems of seven conifer species. All data were compared with daily air temperatures recorded from weather stations located close to the sites. Logistic regressions were used to calculate the probability of xylogenesis and of cambium being active at a given temperature.
Results Xylogenesis lasted from May to October, with a growing period varying from 3 to 5 months depending on location and elevation. Despite the wide geographical range of the monitored sites, temperatures for onset and ending of xylogenesis converged towards narrow ranges with average values around 4–5, 8–9 and 13–14 °C for daily minimum, mean and maximum temperature, respectively. On the contrary, cell division in the cambium stopped in July−August, when temperatures were still high.
Main conclusions Wood formation in conifers occurred when specific critical temperatures were reached. Although the timing and duration of xylogenesis varied among species, sites and years, the estimated temperatures were stable for all trees studied. These results provide biologically based evidence that temperature is a critical factor limiting production and differentiation of xylem cells in cold climates. Although daily temperatures below 4−5 °C are still favourable for photosynthesis, thermal conditions below these values could inhibit the allocation of assimilated carbon to structural investment, i.e. xylem growth.
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TL;DR: This paper reviews current remediation technologies that use chelating agents for the mobilization and removal of potentially toxic metals from contaminated soils and the possible impact of abiotic and biotic soil factors on the toxicity of metals left after the washing of soil and enhanced phytoextraction.
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TL;DR: Although HGT cannot be ruled out as a factor in the evolution of denitrification genes, the analysis suggests that other phenomena, such gene duplication/divergence and lineage sorting, may have differently influenced the evolution.
Abstract: Denitrification is a facultative respiratory pathway in which nitrite (NO2(-)), nitric oxide (NO), and nitrous oxide (N2O) are successively reduced to nitrogen gas (N(2)), effectively closing the nitrogen cycle The ability to denitrify is widely dispersed among prokaryotes, and this polyphyletic distribution has raised the possibility of horizontal gene transfer (HGT) having a substantial role in the evolution of denitrification Comparisons of 16S rRNA and denitrification gene phylogenies in recent studies support this possibility; however, these results remain speculative as they are based on visual comparisons of phylogenies from partial sequences We reanalyzed publicly available nirS, nirK, norB, and nosZ partial sequences using Bayesian and maximum likelihood phylogenetic inference Concomitant analysis of denitrification genes with 16S rRNA sequences from the same organisms showed substantial differences between the trees, which were supported by examining the posterior probability of monophyletic constraints at different taxonomic levels Although these differences suggest HGT of denitrification genes, the presence of structural variants for nirK, norB, and nosZ makes it difficult to determine HGT from other evolutionary events Additional analysis using phylogenetic networks and likelihood ratio tests of phylogenies based on full-length sequences retrieved from genomes also revealed significant differences in tree topologies among denitrification and 16S rRNA gene phylogenies, with the exception of the nosZ gene phylogeny within the data set of the nirK-harboring genomes However, inspection of codon usage and G + C content plots from complete genomes gave no evidence for recent HGT Instead, the close proximity of denitrification gene copies in the genomes of several denitrifying bacteria suggests duplication Although HGT cannot be ruled out as a factor in the evolution of denitrification genes, our analysis suggests that other phenomena, such gene duplication/divergence and lineage sorting, may have differently influenced the evolution of each denitrification gene
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Gyeongsang National University1, University of Tokyo2, Budker Institute of Nuclear Physics3, École Polytechnique Fédérale de Lausanne4, Tata Institute of Fundamental Research5, University of Sydney6, Polish Academy of Sciences7, University of Maribor8, National Taiwan University9, National Central University10, Hanyang University11, Sungkyunkwan University12, University of Melbourne13, Virginia Tech14, University of Ljubljana15, Osaka University16, Nagoya University17, Nara Women's University18, Tohoku Gakuin University19, Kyungpook National University20, Saga University21, Tokyo Institute of Technology22, Yonsei University23, Chiba University24, Niigata University25, Seoul National University26, Graduate University for Advanced Studies27, University of Cincinnati28, Panjab University, Chandigarh29, University of Giessen30, Austrian Academy of Sciences31, Osaka City University32, Tokyo University of Agriculture and Technology33, Toho University34, Kanagawa University35, University of Nova Gorica36, Tokyo Metropolitan University37, National United University38, Korea University39, University of Science and Technology of China40
TL;DR: In this paper, the authors presented a method to detect the presence of a tumor in the human brain using the Web of Science Record created on 2010-11-05, modified on 2017-12-10.
Abstract: Reference EPFL-ARTICLE-154575doi:10.1103/PhysRevLett.100.142001View record in Web of Science Record created on 2010-11-05, modified on 2017-12-10
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TL;DR: Electrochemotherapy is a new, clinically acknowledged method for the treatment of cutaneous and subcutaneous tumours whose advantages are high effectiveness on tumours with different histologies, simple application, minimal side effects and the possibility of effective repetitive treatment.
Abstract: Aim Electrochemotherapy is a local drug delivery approach aimed at treatment with palliative intent of cutaneous and subcutaneous tumour nodules of different histologies Electrochemotherapy, via cell membrane permeabilising electric pulses, potentiates the cytotoxicity of non-permeant or poorly permeant anticancer drugs with high intrinsic cytotoxicity, such as bleomycin or cisplatin, at the site of electric pulse application Methods An overview of preclinical and clinical studies is presented, and the treatment procedure is further critically evaluated Results In clinical studies electrochemotherapy has proved to be a highly efficient and safe approach for treating cutaneous and subcutaneous tumour nodules The treatment response for various tumours (predominantly melanoma) was ∼75% complete and 10% partial response of the treated nodules Conclusions Electrochemotherapy is a new, clinically acknowledged method for the treatment of cutaneous and subcutaneous tumours Its advantages are high effectiveness on tumours with different histologies, simple application, minimal side effects and the possibility of effective repetitive treatment
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TL;DR: This review reports on the current knowledge on structure and regulation of alpha-actinin, a cytoskeletal actin-binding protein and a member of the spectrin superfamily, which comprises spectrin, dystrophin and their homologues and isoforms.
Abstract: Alpha-actinin is a cytoskeletal actin-binding protein and a member of the spectrin superfamily, which comprises spectrin, dystrophin and their homologues and isoforms. It forms an anti-parallel rod-shaped dimer with one actin-binding domain at each end of the rod and bundles actin filaments in multiple cell-type and cytoskeleton frameworks. In non-muscle cells, alpha-actinin is found along the actin filaments and in adhesion sites. In striated, cardiac and smooth muscle cells, it is localized at the Z-disk and analogous dense bodies, where it forms a lattice-like structure and stabilizes the muscle contractile apparatus. Besides binding to actin filaments alpha-actinin associates with a number of cytoskeletal and signaling molecules, cytoplasmic domains of transmembrane receptors and ion channels, rendering it important structural and regulatory roles in cytoskeleton organization and muscle contraction. This review reports on the current knowledge on structure and regulation of alpha-actinin.
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TL;DR: In this paper, the authors evaluated 13 sweet cherry cultivars for their total phenolic content and antioxidant activity and found that the correlation of antioxidant activity with total phenolics content and content of anthocyanins was cultivar dependent.
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TL;DR: In this paper, the authors refer to the De Keyser-Vanhove model of a competitive destination, which was applied to Slovenia in 1998, and study the Integrated model of destination competitiveness developed in a collaborative effort of researchers dealing with the cases of Korea and Australia and examines its determinants and individual competitive indicators as perceived by Slovenian tourist stakeholders on the supply side.
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Joint Institute for Nuclear Astrophysics1, Ohio State University2, Texas Tech University3, University of Texas at Austin4, Max Planck Society5, University of Ljubljana6, Australian National University7, Fermilab8, University of California, Santa Cruz9, Rensselaer Polytechnic Institute10, University of Chicago11, Apache Corporation12
TL;DR: In this paper, the accuracy and precision of the current SEGUE (Sloan Extension for Galactic Understanding and Exploration) Stellar Parameter Pipeline (SSPP) is validated by comparing these estimates for selected members of three globular clusters (M 13, M 15, and M 2) and two open clusters (NGC 2420 and M 67) to the literature values.
Abstract: We validate the accuracy and precision of the current SEGUE (Sloan Extension for Galactic Understanding and Exploration) Stellar Parameter Pipeline (SSPP), which determines stellar atmospheric parameters (effective temperature, surface gravity, and metallicity) and radial velocities (RVs), by comparing these estimates for selected members of three globular clusters (M 13, M 15, and M 2) and two open clusters (NGC 2420 and M 67) to the literature values. Spectroscopic and photometric data obtained during the course of the original Sloan Digital Sky Survey (SDSS-I) and its first extension (SDSS-II/SEGUE) are used to determine atmospheric parameter and RV estimates for stars in these clusters. Based on the scatter in the metallicities derived for the members of each cluster, we quantify the typical uncertainty of the SSPP values, σ ([Fe/H]) = 0.13 dex for stars in the range of –0.3 ≤ g – r ≤ 1.3 and 2.0 ≤ log g ≤ 5.0, at least over the metallicity interval spanned by the clusters studied (–2.3 ≤ [Fe/H] ≤ 0). The surface gravities and effective temperatures derived by the SSPP are also compared with those estimated from the comparison of color-magnitude diagrams with stellar evolution models; we find satisfactory agreement (σ(T eff)< 200 K and σ(log g) ≤ 0.4 dex).
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TL;DR: In this paper, the effect of masonry infills on the seismic response of a four-storey reinforced concrete frame has been studied using the N2 method, which is based on pushover analysis and the inelastic spectrum approach.
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TL;DR: It is proposed that degradation of anti-apoptotic Bcl-2 family members by lysosomal cathepsins synergizes with cathepsypsin-mediated activation of Bid to trigger a mitochondrial pathway to apoptosis.
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Kent State University1, Tel Aviv University2, Massachusetts Institute of Technology3, California State University, Los Angeles4, University of Glasgow5, Argonne National Laboratory6, Syracuse University7, Prince Mohammad bin Fahd University8, University of Maryland, College Park9, Florida International University10, Thomas Jefferson National Accelerator Facility11, Seoul National University12, University of Virginia13, Rutgers University14, Kharkov Institute of Physics and Technology15, College of William & Mary16, Old Dominion University17, University of Saskatchewan18, University of Massachusetts Amherst19, University of Kentucky20, Norfolk State University21, Temple University22, Yerevan Physics Institute23, University of Ljubljana24, University of Illinois at Urbana–Champaign25
TL;DR: Scattering experiments show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton- Proton pairs and, by inference, neutron-neutron pairs, which has implications for understanding cold dense nuclear systems such as neutron stars.
Abstract: The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, in which a proton is knocked out of the nucleus with high-momentum transfer and high missing momentum, show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars.
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TL;DR: The biological guidelines for tissue engineering of bone, the bioreactor cultivation of human mesenchymal stem cells on three-dimensional scaffolds, and the need for vascularization and functional integration of bone grafts following implantation are discussed.
Abstract: The tremendous need for bone tissue in numerous clinical situations and the limited availability of suitable bone grafts are driving the development of tissue engineering approaches to bone repair. In order to engineer viable bone grafts, one needs to understand the mechanisms of native bone development and fracture healing, as these processes should ideally guide the selection of optimal conditions for tissue culture and implantation. Engineered bone grafts have been shown to have capacity for osteogenesis, osteoconduction, osteoinduction and osteointegration - functional connection between the host bone and the graft. Cells from various anatomical sources in conjunction with scaffolds and osteogenic factors have been shown to form bone tissue in vitro. The use of bioreactor systems to culture cells on scaffolds before implantation further improved the quality of the resulting bone grafts. Animal studies confirmed the capability of engineered grafts to form bone and integrate with the host tissues. However, the vascularization of bone remains one of the hurdles that need to be overcome if clinically sized, fully viable bone grafts are to be engineered and implanted. We discuss here the biological guidelines for tissue engineering of bone, the bioreactor cultivation of human mesenchymal stem cells on three-dimensional scaffolds, and the need for vascularization and functional integration of bone grafts following implantation.
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TL;DR: Freshwater amphipods are greatly polyphyletic, continental invasions have taken place repeatedly in different time frames and regions of the world, and have had great impacts on European fluvial ecosystems.
Abstract: Amphipods are brooding peracaridan crustaceans whose young undergo direct development, with no independent larval dispersal stage. Most species are epibenthic, benthic, or subterranean. There are some 1,870 amphipod species and subspecies recognized from fresh or inland waters worldwide at the end of 2005. This accounts for 20% of the total known amphipod diversity. The actual diversity may still be several-fold. Amphipods are most abundant in cool and temperate environments; they are particularly diversified in subterranean environments and in running waters (fragmented habitats), and in temperate ancient lakes, but are notably rare in the tropics. Of the described freshwater taxa 70% are Palearctic, 13% Nearctic, 7% Neotropical, 6% Australasian and 3% Afrotropical. Approximately 45% of the taxa are subterranean; subterranean diversity is highest in the karst landscapes of Central and Southern Europe (e.g., Niphargidae), North America (Crangonyctidae), and Australia (Paramelitidae). The majority of Palearctic epigean amphipods are in the superfamily Gammaroidea, whereas talitroid amphipods (Hyalella) account for all Neotropic and much of the Nearctic epigean fauna. Major concentrations of endemic species diversity occur in Southern Europe, Lake Baikal, the Ponto-Caspian basin, Southern Australia (including Tasmania), and the south-eastern USA. Endemic family diversity is similarly centered in the Western Palearctic and Lake Baikal. Freshwater amphipods are greatly polyphyletic, continental invasions have taken place repeatedly in different time frames and regions of the world. In the recent decades, human mediated invasions of Ponto-Caspian amphipods have had great impacts on European fluvial ecosystems.
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TL;DR: In this paper, the authors estimate how various interphase contacts affect the electrode kinetics and find that the high-frequency impedance arc is due to the contact impedance between the metal and the electrode material.
Abstract: Li insertion electrodes are made by pressing a mixture of active material and additives on a metallic substrate. Here we estimate how various interphase contacts affect the electrode kinetics. We apply variable external mechanical pressure onto different cathodes and measure their impedance response. Similar experiments are performed on dry composites in contact with: Al or Cu foil, or Ag paste. Most surprisingly, we find that the high-frequency impedance arc is due to the contact impedance between the metal and the electrode material. This is in fundamental contradiction with previous interpretations. We propose an equivalent circuit explaining the observed phenomena.
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University of North Carolina at Chapel Hill1, Trinity College, Dublin2, Carol Davila University of Medicine and Pharmacy3, University of Malaya4, National and Kapodistrian University of Athens5, Cardiff University6, Karolinska Institutet7, Academic Center for Dentistry Amsterdam8, Mahidol University9, University of Ljubljana10, University of Birmingham11, University of Nevada, Las Vegas12, Thammasat University13, Sofia Medical University14, University of Zagreb15
TL;DR: It is suggested that the set of recommendations proposed can improve students' quality of life and well-being, enhance their total educational experience and positively influence their future careers as oral health physicians.
Abstract: Dental education is regarded as a complex, demanding and often stressful pedagogical procedure. Undergraduates, while enrolled in programmes of 4-6 years duration, are required to attain a unique and diverse collection of competences. Despite the major differences in educational systems, philosophies, methods and resources available worldwide, dental students' views regarding their education appear to be relatively convergent. This paper summarizes dental students' standpoint of their studies, showcases their experiences in different educational settings and discusses the characteristics of a positive academic environment. It is a consensus opinion that the 'students' perspective' should be taken into consideration in all discussions and decisions regarding dental education. Moreover, it is suggested that the set of recommendations proposed can improve students' quality of life and well-being, enhance their total educational experience and positively influence their future careers as oral health physicians. The 'ideal' academic environment may be defined as one that best prepares students for their future professional life and contributes towards their personal development, psychosomatic and social well-being. A number of diverse factors significantly influence the way students perceive and experience their education. These range from 'class size', 'leisure time' and 'assessment procedures' to 'relations with peers and faculty', 'ethical climate' and 'extra-curricular opportunities'. Research has revealed that stress symptoms, including psychological and psychosomatic manifestations, are prevalent among dental students. Apparently some stressors are inherent in dental studies. Nevertheless, suggested strategies and preventive interventions can reduce or eliminate many sources of stress and appropriate support services should be readily available. A key point for the Working Group has been the discrimination between 'teaching' and 'learning'. It is suggested that the educational content should be made available to students through a variety of methods, because individual learning styles and preferences vary considerably. Regardless of the educational philosophy adopted, students should be placed at the centre of the process. Moreover, it is critical that they are encouraged to take responsibility for their own learning. Other improvements suggested include increased formative assessment and self-assessment opportunities, reflective portfolios, collaborative learning, familiarization with and increased implementation of information and communication technology applications, early clinical exposure, greater emphasis on qualitative criteria in clinical education, community placements, and other extracurricular experiences such as international exchanges and awareness of minority and global health issues. The establishment of a global network in dental education is firmly supported but to be effective it will need active student representation and involvement.
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TL;DR: In this paper, the Lindblad master equation for an arbitrary quadratic system of n fermions is solved explicitly in terms of diagonalization of a 4n?4n matrix, provided that all bath operators are linear in the fermionic variables.
Abstract: The Lindblad master equation for an arbitrary quadratic system of n fermions is solved explicitly in terms of diagonalization of a 4n?4n matrix, provided that all Lindblad bath operators are linear in the fermionic variables. The method is applied to the explicit construction of non-equilibrium steady states (NESS) and the calculation of asymptotic relaxation rates in the far from equilibrium problem of heat and spin transport in a nearest neighbour Heisenberg XY spin-1/2 chain in a transverse magnetic field.
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TL;DR: Evaluating the phenolic profile of fig fruit with the HPLC-PDA system identified the following phenolics: gallic acid, chlorogenic acid, syringic Acid, (+)-catechin, (−)-epicatechin and rutin.