The midpalatal suture (MPS) corresponds to the tissue that joins the two maxillary bones. Understanding the mechanical behavior of this tissue is of particular interest to those patients who require ...orthodontic treatments such as Rapid Maxillary Expansion (RME). The objective of this research was to observe the influence of interdigitation and collagen fibers on the mechanical response of MPS. To this end, a finite element analysis in two-dimensional models of the bone-suture-bone interface was performed considering the characteristics of the MPS. The geometry of the suture was modeled with 4 different levels of interdigitation: null, moderate, scalloped and fractal. The influence of collagen fibers, aligned transversely along the suture, was considered by incorporating linked structures of the bone fronts. According to the results, the factor that has the greatest impact on the magnitude and distribution of stresses is the interdigitation degree. A higher level of interdigitation produces an increase in tissue stiffness and a lower influence of collagen fibers on the mechanical response of the tissue. Therefore, this research contributes to the understanding of the MPS biomechanics by providing information that may be useful to health staff when evaluating the feasibility of procedures such as RME.
Graphical Abstract
Hemibrycon iqueima sp. nov., is described from small streams in the Magdalena drainage at the foothills of the western slope of the Eastern Cordillera of the Colombian Andes, Suarez municipality, ...Tolima Department, Colombia. The new species is distinguished from its congeners in the Magdalena–Cauca River basin by a combination of characters related to snout–anal‐fin origin length, head length, dorsal–pectoral fin distance, dorsal‐fin–hypural distance, postorbital distance, orbital diameter, snout length, number of total vertebrae, pre‐dorsal scales, scale rows between anal‐fin origin and lateral line, number of branched rays of the anal fin, maxillary teeth number and number and arrangement of hooks on the branched rays of the pectoral and dorsal fins. In addition, the validity of this species is supported by previous molecular analyses that included specimens of the new species that had been erroneously identified. Phylogenetic relationships between the new species and congeners from Pacific coast basins are discussed.
Gaia Data Release 2 Bastian, U.; Babusiaux, C.; Breddels, M. A. ...
Astronomy and astrophysics (Berlin),
08/2018, Letnik:
616, Številka:
A12
Journal Article, Web Resource
Recenzirano
Odprti dostop
Context.
Aims.
The goal of this paper is to demonstrate the outstanding quality of the second data release of the
Gaia
mission and its power for constraining many different aspects of the dynamics of ...the satellites of the Milky Way. We focus here on determining the proper motions of 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system, and the Large and Small Magellanic Clouds.
Methods.
Using data extracted from the
Gaia
archive, we derived the proper motions and parallaxes for these systems, as well as their uncertainties. We demonstrate that the errors, statistical and systematic, are relatively well understood. We integrated the orbits of these objects in three different Galactic potentials, and characterised their properties. We present the derived proper motions, space velocities, and characteristic orbital parameters in various tables to facilitate their use by the astronomical community.
Results.
Our limited and straightforward analyses have allowed us for example to (
i
) determine absolute and very precise proper motions for globular clusters; (
ii
) detect clear rotation signatures in the proper motions of at least five globular clusters; (
iii
) show that the satellites of the Milky Way are all on high-inclination orbits, but that they do not share a single plane of motion; (
iv
) derive a lower limit for the mass of the Milky Way of 9.1
-2.6
+6.2
× 10
11
M
⊙
based on the assumption that the Leo I dwarf spheroidal is bound; (
v
) derive a rotation curve for the Large Magellanic Cloud based solely on proper motions that is competitive with line-of-sight velocity curves, now using many orders of magnitude more sources; and (
vi
) unveil the dynamical effect of the bar on the motions of stars in the Large Magellanic Cloud.
Conclusions.
All these results highlight the incredible power of the
Gaia
astrometric mission, and in particular of its second data release.
Purpose
Evaluate the percentage of patients with prostate cancer treated with luteinizing hormone-releasing hormone analogues (LHRHa) that develop castration resistance after a follow-up period of ...3 years. The secondary objective is to evaluate the variables potentially related to the progression to castration resistant prostate cancer (CRPC).
Methods
A post-authorization, nation-wide, multicenter, prospective, observational, and longitudinal study that included 416 patients treated with LHRHa between 2012 and 2017 is presented. Patients were followed for 3 years or until development of CRPC, thus completing a per-protocol population of 350 patients. A Cox regression analysis was carried out to evaluate factors involved in progression to CRPC.
Results
After 3 years of treatment with LHRHa 18.2% of patients developed CRPC. In contrast, in the subgroup analysis, 39.6% of the metastatic patients developed CRPC, compared with 8.8% of the non-metastatic patients. The patients with the highest risk of developing CRPC were those with a nadir prostate-specific antigen (PSA) > 2 ng/ml (HR 21.6; 95% CI 11.7–39.8;
p
< 0.001) and those receiving concomitant medication, most commonly bicalutamide (HR 1.8; 95% CI 1–3.1,
p
= 0.0431).
Conclusions
The proportion of metastatic patients developing CRPC after 3 years of treatment with LHRHa is consistent with what has been previously described in the literature. In addition, this study provides new findings on CRPC in non-metastatic patients. Concomitant medication and nadir PSA are statistically significant predictive factors for the time to diagnosis of CRPC, the nadir PSA being the strongest predictor.
Highly porous homoleptic Ni(bpb) and Zn(bpb) materials have been obtained by reaction of nickel(II) and zinc(II) salts with the deprotonated form of the 1,4-(4-bispyrazolyl)benzene ligand (H2bpb). ...Ab-initio structure solution methods and thermodiffractometry have allowed the determination of their crystal structures, framework flexibility, and thermal stability. The different stereochemical requirements of the Ni(II) and Zn(II) ions induce, in Ni(bpb) and Zn(bpb), rhombic and square channels, respectively, accounting for 57 and 65% of the total cell volume. The two materials feature high adsorption capacities toward small gaseous molecules (N2 and Ar at 77 K, CO2 and CH4 at 273 K), peaking at 22 mmol g−1 of N2 in the case of the zinc(II) derivative, which is reflected by a very large surface area (above 2000 m2 g−1). The flexibility, size, and hydrophobic nature of their channels are adequate also for the incorporation of organic vapors. In this regard, the adsorption of benzene and cyclohexane has been studied under static conditions at 303 K, while that of thiophene has been investigated in dynamic conditions, by measurement, at 298 K, of the breakthrough curves of a flow of CH4/CO2 containing 30 ppm of thiophene. Ni(bpb) and Zn(bpb) are outperforming adsorbents, uptaking up to 0.34 g of thiophene per gram of material. The presence of humidity (60%), which is a major drawback for practical applications of MOFs, does not significantly affect the performance of Ni(bpb) in the removal of thiophene, at variance with Zn(bpb) and HKUST-1, Cu3(btc)2 (btc = benzene-1,3,5-tricarboxylate), which become ineffective in the presence of moisture. Additional XRPD studies have been performed on benzene-loaded Ni(bpb) samples in order to shed some light on the affinity of this material for aromatic guests.
Non-Dominated Sorting (NDS) is the most time-consuming procedure used in the majority of evolutionary multiobjective optimization algorithms that are based on Pareto dominance ranking without regard ...to the computation time of the objective functions. It can be accelerated by the exploitation of its parallelism on High Performance Computing systems, that provide heterogeneous processing units, such as multicore processors and GPUs. The optimization of energy efficiency of such systems is a challenge in scientific computation since it depends on the kind of processing which is performed. Our interest is to solve NDS in an efficient way concerning both runtime and energy consumption. In literature, performance improvement has been extensively studied. Recently, a sequential Best Order Sort (BOS) algorithm for NDS has been introduced as one of the most efficient one in terms of practical performance. This work is focused on the acceleration of the NDS on modern architectures. Two efficient parallel NDS algorithms based on Best Order Sort, are introduced, MC-BOS and GPU-BOS. Both algorithms start with the fast sorting of population by objectives. MC-BOS computes in parallel the analysis of the population by objectives on the multicore processors. GPU-BOS is based on the principles of Best Order Sort, with a new scheme designed to harness the massive parallelism provided by GPUs. A wide experimental study of both algorithms on several kinds of CPU and GPU platforms has been carried out. Runtime and energy consumption are analysed to identify the best platform/algorithm of the parallel NDS for every particular population size. The analysis of obtained results defines criteria to help the user when selecting the optimal parallel version/platform for particular dimensions of NDS. The experimental results show that the new parallel NDS algorithms overcome the sequential Best Order Sort in terms of the performance and energy efficiency in relevant factors.
Gaia Data Release 2 Hobbs, D.; Michalik, D.; Geyer, R. ...
Astronomy and astrophysics (Berlin),
08/2018, Letnik:
616, Številka:
A14
Journal Article, Web Resource
Recenzirano
Odprti dostop
Context. The second release of Gaia data ( Gaia DR2) contains the astrometric parameters for more than half a million quasars. This set defines a kinematically non-rotating reference frame in the ...optical domain. A subset of these quasars have accurate VLBI positions that allow the axes of the reference frame to be aligned with the International Celestial Reference System (ICRF) radio frame. Aims. We describe the astrometric and photometric properties of the quasars that were selected to represent the celestial reference frame of Gaia DR2 ( Gaia -CRF2), and to compare the optical and radio positions for sources with accurate VLBI positions. Methods. Descriptive statistics are used to characterise the overall properties of the quasar sample. Residual rotation and orientation errors and large-scale systematics are quantified by means of expansions in vector spherical harmonics. Positional differences are calculated relative to a prototype version of the forthcoming ICRF3. Results. Gaia -CRF2 consists of the positions of a sample of 556 869 sources in Gaia DR2, obtained from a positional cross-match with the ICRF3-prototype and AllWISE AGN catalogues. The sample constitutes a clean, dense, and homogeneous set of extragalactic point sources in the magnitude range G ≃ 16 to 21 mag with accurately known optical positions. The median positional uncertainty is 0.12 mas for G < 18 mag and 0.5 mas at G = mag. Large-scale systematics are estimated to be in the range 20 to 30 μ as. The accuracy claims are supported by the parallaxes and proper motions of the quasars in Gaia DR2. The optical positions for a subset of 2820 sources in common with the ICRF3-prototype show very good overall agreement with the radio positions, but several tens of sources have significantly discrepant positions. Conclusions. Based on less than 40% of the data expected from the nominal Gaia mission, Gaia -CRF2 is the first realisation of a non-rotating global optical reference frame that meets the ICRS prescriptions, meaning that it is built only on extragalactic sources. Its accuracy matches the current radio frame of the ICRF, but the density of sources in all parts of the sky is much higher, except along the Galactic equator.
Abstract
Summary
TomoEED is an optimized software tool for fast feature-preserving noise filtering of large 3D tomographic volumes on CPUs and GPUs. The tool is based on the anisotropic nonlinear ...diffusion method. It has been developed with special emphasis in the reduction of the computational demands by using different strategies, from the algorithmic to the high performance computing perspectives. TomoEED manages to filter large volumes in a matter of minutes in standard computers.
Availability and implementation
TomoEED has been developed in C. It is available for Linux platforms at http://www.cnb.csic.es/%7ejjfernandez/tomoeed.
Supplementary information
Supplementary data are available at Bioinformatics online.
Gaia Data Release 2 Glass, F.; Brown, A. G. A.; de Bruijne, J. H. J. ...
Astronomy and astrophysics (Berlin),
03/2019, Letnik:
623
Journal Article, Web Resource
Recenzirano
Odprti dostop
Context.
The ESA
Gaia
mission provides a unique time-domain survey for more than 1.6 billion sources with
G
≲ 21 mag.
Aims.
We showcase stellar variability in the Galactic colour-absolute magnitude ...diagram (CaMD). We focus on pulsating, eruptive, and cataclysmic variables, as well as on stars that exhibit variability that is due to rotation and eclipses.
Methods.
We describe the locations of variable star classes, variable object fractions, and typical variability amplitudes throughout the CaMD and show how variability-related changes in colour and brightness induce “motions”. To do this, we use 22 months of calibrated photometric, spectro-photometric, and astrometric
Gaia
data of stars with a significant parallax. To ensure that a large variety of variable star classes populate the CaMD, we crossmatched
Gaia
sources with known variable stars. We also used the statistics and variability detection modules of the
Gaia
variability pipeline. Corrections for interstellar extinction are not implemented in this article.
Results. Gaia
enables the first investigation of Galactic variable star populations in the CaMD on a similar, if not larger, scale as was previously done in the Magellanic Clouds. Although the observed colours are not corrected for reddening, distinct regions are visible in which variable stars occur. We determine variable star fractions to within the current detection thresholds of
Gaia
. Finally, we report the most complete description of variability-induced motion within the CaMD to date.
Conclusions. Gaia
enables novel insights into variability phenomena for an unprecedented number of stars, which will benefit the understanding of stellar astrophysics. The CaMD of Galactic variable stars provides crucial information on physical origins of variability in a way that has previously only been accessible for Galactic star clusters or external galaxies. Future
Gaia
data releases will enable significant improvements over this preview by providing longer time series, more accurate astrometry, and additional data types (time series BP and RP spectra, RVS spectra, and radial velocities), all for much larger samples of stars.
We present the first observation of K^{-} and ϕ absorption within nuclear matter by means of π^{-}-induced reactions on C and W targets at an incident beam momentum of 1.7 GeV/c studied with HADES ...at SIS18/GSI. The double ratio (K^{-}/K^{+})_{W}/(K^{-}/K^{+})_{C} is found to be 0.319±0.009(stat)_{-0.012}^{+0.014}(syst) indicating a larger absorption of K^{-} in heavier targets as compared to lighter ones. The measured ϕ/K^{-} ratios in π^{-}+C and π^{-}+W reactions within the HADES acceptance are found to be equal to 0.55±0.04(stat)_{-0.07}^{+0.06}(syst) and to 0.63±0.06(stat)_{-0.11}^{+0.11}(syst), respectively. The similar ratios measured in the two different reactions demonstrate for the first time experimentally that the dynamics of the ϕ meson in nuclear medium is strongly coupled to the K^{-} dynamics. The large difference in the ϕ production off C and W nuclei is discussed in terms of a strong ϕN in-medium coupling. These results are relevant for the description of heavy-ion collisions and the structure of neutron stars.
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