476 research outputs found
Comparison Tests of the Column Coefficient and the Gravity Coefficient Models
This study presents a comparison of the 1947, 1958, 1963, 1970, and 1980 regional outputs estimated using the column coefficient and gravity coefficient models. An evaluation is made of the accuracy of the two models in estimating 1947, 1958, and 1963 outputs. A detailed review of the industrial and regional estimation errors is provided by the authors, supplemented by appendix tables showing the errors for each of 10 industries in each of 9 regions
Arbitrary-order Hilbert spectral analysis and intermittency in solar wind density fluctuations
The properties of inertial and kinetic range solar wind turbulence have been
investigated with the arbitrary-order Hilbert spectral analysis method, applied
to high-resolution density measurements. Due to the small sample size, and to
the presence of strong non-stationary behavior and large-scale structures, the
classical structure function analysis fails to detect power law behavior in the
inertial range, and may underestimate the scaling exponents. However, the
Hilbert spectral method provides an optimal estimation of the scaling
exponents, which have been found to be close to those for velocity fluctuations
in fully developed hydrodynamic turbulence. At smaller scales, below the proton
gyroscale, the system loses its intermittent multiscaling properties, and
converges to a monofractal process. The resulting scaling exponents, obtained
at small scales, are in good agreement with those of classical fractional
Brownian motion, indicating a long-term memory in the process, and the absence
of correlations around the spectral break scale. These results provide
important constraints on models of kinetic range turbulence in the solar wind
Purveyors of fine halos. II. Chemodynamical association of halo stars with Milky Way globular clusters
We present chemodynamical links between the present-day Milky Way halo field
star population and Galactic globular clusters (GCs) using a dataset that
combines information from the space mission and the Sloan
Digital Sky Survey (SDSS-IV, DR14). Moreover, we incorporated a sample of halo
giant stars with a distinct chemical signature (strong CN bandheads) that
resembles the light-elements anomaly otherwise only seen in the second
generation of GC stellar populations. Using three different tagging techniques,
we could successfully establish unique associations between 151 extratidal
stars in the neighborhood of eight GCs. In addition, we traced the possible
origin of about of the sample of CN-strong giants to their potential
host clusters. Several of the involved GCs have been brought into connection
with the Gaia-Enceladus and Sequoia merger events. By establishing kinematic
and chemical connections between 17 CN-strong stars and their surrounding
fields, we could identify co-moving groups of stars at the same [Fe/H] with a
possible cluster origin. We found strong evidence that four CN-strong stars and
their associates are connected to the Sagittarius stream whilst their tightly
confined [Fe/H] may hint to a birth site in M 54. Finally, we provide tentative
estimates for the fraction of first-generation cluster stars among all stars
lost to the halo. In the immediate cluster vicinity, this value amounts to
while the associations in the halo field rather imply
. We speculate that -- if proven real by spectroscopic
follow-up -- the disparity between these numbers could indicate a major
contribution of low-mass clusters to the overall number of stars escaped to the
halo or, alternatively, point toward a strong mass loss from the first
generation during early cluster dissolution. [abridged]Comment: 20 pages (+9 pages of appendices), 39 figures, 4 tables, accepted for
publication in A&
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A Data Parallel Finite Element Method for Computational Fluid Dynamics on the Connection Machine System
A finite element method for computational the Connection Machine systems CM-2 and CM-200. An implicit iterative solution strate-
gy, based on the preconditioned matrix-free GMRES algorithm, is employed. Parallel data structures built on both nodal and elemental sets are used to achieve maximum parallelization. Communication primitives provided through the Connection Machine Scientific Software Library substantially improved the overall performance of the program. Computations of three-dimensional compressible flows using unstructured meshes having close to one million elements, such as a complete airplane, demonstrate that the Connection Machine systems are suitable for these applications. Performance comparisons are also carried out with the vector computers Cray Y-MP and Convex C-1.Engineering and Applied Science
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Mesh Decomposition and Communication Procedures for Finite Element Applications on the Connection Machine CM-5 System
The objective of this paper is to analyze the impact of data mapping strategies on the performance of finite element applications. First, we describe a parallel mesh decomposition algorithm based on recursive spectral bisection used to partition the mesh into element blocks. A simple heuristic algorithm then renumbers the mesh nodes. Large three-dimensional meshes demonstrate the efficiency of those mapping strategies and assess the performance of a finite element program for fluid dynamics.Engineering and Applied Science
Distinct phenotype of neutrophil, monocyte, and eosinophil populations indicates altered myelopoiesis in a subset of patients with multiple myeloma
Hematologic malignancies, including multiple myeloma (MM), promote systemic immune dysregulation resulting in an alteration and increased plasticity of myeloid cell subsets. To determine the heterogeneity of the myeloid cell compartment in the peripheral blood of patients with MM, we performed a detailed investigation of the phenotype and function of myeloid subpopulations. We report that a subset of MM patients exhibits a specific myeloid cell phenotype indicative of altered myelopoiesis characterized by significant changes in the properties of circulating granulocytic, monocytic, and eosinophilic populations. The subset, referred to as MM2, is defined by a markedly elevated level of CD64 (FcγRI) on the surface of circulating neutrophils. Compared to healthy controls or MM1 patients displaying intermediate levels of CD64, neutrophils from MM2 patients exhibit a less differentiated phenotype, low levels of CD10 and CXC chemokine receptor 2 (CXCR2), increased capacity for the production of mitochondrial reactive oxygen species, and an expansion of CD16neg immature neutrophil subset. Classical and patrolling monocytes from MM2 patients express elevated levels of CD64 and activation markers. MM2 eosinophils display lower levels of C-C Chemokine receptor 3 (CCR3), Toll-like receptor 4 (TLR4, CD284), and tissue factor (TF, CD142). The MM2 (CD64high) phenotype is independent of age, race, sex, and treatment type. Characteristic features of the MM2 (CD64high) phenotype are associated with myeloma-defining events including elevated involved/uninvolved immunoglobulin free light chain (FLC) ratio at diagnosis. Detailed characterization of the altered myeloid phenotype in multiple myeloma will likely facilitate the identification of patients with an increased risk of disease progression and open new avenues for the rational design of novel therapeutic approaches
Project Final Report – FREEDOM ICT-248891
This document is the final publishable summary report of the objective and work carried out within the European Project FREEDOM, ICT-248891.This document is the final publishable summary report of the objective and work carried out within the European Project FREEDOM, ICT-248891.Preprin
Candidate genes for obstructive sleep apnea in non-syndromic children with craniofacial dysmorphisms – a narrative review
Pediatric obstructive sleep apnea (POSA) is a complex disease with multifactorial etiopathogenesis. The presence of craniofacial dysmorphisms influencing the patency of the upper airway is considered a risk factor for POSA development. The craniofacial features associated with sleep-related breathing disorders (SRBD) – craniosynostosis, retrognathia and micrognathia, midface and maxillary hypoplasia – have high heritability and, in a less severe form, could be also found in non-syndromic children suffering from POSA. As genetic factors play a role in both POSA and craniofacial dysmorphisms, we hypothesize that some genes associated with specific craniofacial features that are involved in the development of the orofacial area may be also considered candidate genes for POSA. The genetic background of POSA in children is less explored than in adults; so far, only one genome-wide association study for POSA has been conducted; however, children with craniofacial disorders were excluded from that study. In this narrative review, we discuss syndromes that are commonly associated with severe craniofacial dysmorphisms and a high prevalence of sleep-related breathing disorders (SRBD), including POSA. We also summarized information about their genetic background and based on this, proposed 30 candidate genes for POSA affecting craniofacial development that may play a role in children with syndromes, and identified seven of these genes that were previously associated with craniofacial features risky for POSA development in non-syndromic children. The evidence-based approach supports the proposition that variants of these candidate genes could lead to POSA phenotype even in these children, and, thus, should be considered in future research in the general pediatric population
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