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131.
The Boolean Vector Machine (BVM) is a large network of extremely small processors with very small memories operating in SIMD mode using bit serial arithmetic. Individual processors communicate via a hardware implementation of the Cube Connected Cycles (CCC) network. A prototype BVM with 2048 processing elements, each with 200 binary bits of memory, is currently being built using VLSI technology.
The BVM's bit-serial arithmetic and the small memories of individual processors are apparently a drawback to its effectiveness when applied to large numerical problems. In this paper we analyze an implementation of a basic matrix-vector iteration algorithm for sparse matrices on the BVM. We show that a 220 Pe BVM can deliver over 1 billion (109) useful floating-point operations per second for this problem. The algorithm is expressed in a new language (BVL) which has been defined for programming the BVM. 相似文献
132.
This paper describes MetaIndex, an automatic indexing program that creates symbolic representations of documents for the purpose of document retrieval. MetaIndex uses a simple transition network parser to recognize a language that is derived from the set of main concepts in the Unified Medical Language System Metathesaurus (Meta-1). MetaIndex uses a hierarchy of medical concepts, also derived from Meta-1, to represent the content of documents. The goal of this approach is to improve document retrieval performance by better representation of documents. An evaluation method is described, and the performance of MetaIndex on the task of indexing the Slice of Life medical image collection is reported. 相似文献
133.
J. Beger G. Wagner U. Dinjus H. Grls E. Uhlig J. Sieler 《Advanced Synthesis \u0026amp; Catalysis》1983,325(2):211-224
The Coordinative Behaviour of N-Substituted 2-(Δ2-Imidazolin-2-yl)-phenols as Metal Extractants N-Substituted 2-(Δ2-imidazolin-2-yl)-phenols (R4NNOH) are obtained by the reaction of N-alkyl diaminoethane-1, 2 and 2-hydroxybenzoic acid esters. In contrast to many other copper(II) complexes with the donor set N2O22−( A ), the species Cu(R4NNO)2( B ) are easily soluble in nonpolar solvents. The reason is the monomeric square-planar structure of B , which differs from the polymeric distorted octahedral structure of A . The two maxima in the vis-spectra of Cu(R4NNO)2 and Ni(R4NNO)2 are assigned to the 3 dxy → 3 dx2-y2 and the 3 dxz, 3 dyz → 3 dx2-y2 electron transitions. The shift of these maxima, which is connected with the dissolution in chloroform, is explained by the formation of hydrogen bonds between the solvent and the N-alkylated nitrogen atoms of the ligands. 1H-n. m. r.-spectra and solubility of the ligands and the crystal structure of Cu[(C4H9)NNO]2 are described. 相似文献
134.
Elodie Belnoue Alexis Vogelzang Natalie E. Nieuwenhuizen Magdalena A. Krzyzaniak Stephanie Darbre Mario Kreutzfeldt Ingrid Wagner Doron Merkler Paul-Henri Lambert Stefan H. E. Kaufmann Claire-Anne Siegrist Daniel D. Pinschewer 《International journal of molecular sciences》2022,23(5)
Mycobacterium tuberculosis (Mtb) represents a major burden to global health, and refined vaccines are needed. Replication-deficient lymphocytic choriomeningitis virus (rLCMV)-based vaccine vectors against cytomegalovirus have proven safe for human use and elicited robust T cell responses in a large proportion of vaccine recipients. Here, we developed an rLCMV vaccine expressing the Mtb antigens TB10.4 and Ag85B. In mice, rLCMV elicited high frequencies of polyfunctional Mtb-specific CD8 and CD4 T cell responses. CD8 but not CD4 T cells were efficiently boosted upon vector re-vaccination. High-frequency responses were also observed in neonatally vaccinated mice, and co-administration of rLCMV with Expanded Program of Immunization (EPI) vaccines did not result in substantial reciprocal interference. Importantly, rLCMV immunization significantly reduced the lung Mtb burden upon aerosol challenge, resulting in improved lung ventilation. Protection was associated with increased CD8 T cell recruitment but reduced CD4 T cell infiltration upon Mtb challenge. When combining rLCMV with BCG vaccination in a heterologous prime-boost regimen, responses to the rLCMV-encoded Mtb antigens were further augmented, but protection was not significantly different from rLCMV or BCG vaccination alone. This work suggests that rLCMV may show utility for neonatal and/or adult vaccination efforts against pulmonary tuberculosis. 相似文献
135.
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137.
Wagner L. Priamo Alana M. de CezaroStéphani C. Benetti J. Vladimir OliveiraSandra R.S. Ferreira 《The Journal of Supercritical Fluids》2011,56(2):137-143
The main objective of this work was to investigate the characteristics of the in vitro release of β-carotene encapsulated in poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) using the solution enhanced dispersion by supercritical fluids (SEDS) technique. The release tests were performed using encapsulated complex with solute loading from 2.24 to 27.5% and encapsulation efficiency from 7.75 to 55.54%. The release profile assays were performed in ethyl acetate, n-hexane and anhydrous ethanol, and monitored by UV-vis spectrophotometer concentration analysis. Results indicated higher initial release rates in ethyl acetate and in n-hexane, with cumulative release percentage varying from 31.50 to 69.58% and from 42.08 to 55.96%, respectively. For anhydrous ethanol the maximum concentration was reached at 180 min, 300 min and 10 days, depending on the initial amount of β-carotene, with cumulative release ranging from 45.27 to 88.22%. In general, the β-carotene release can be controlled by the organic solvent used and by the initial amount of solute encapsulated, aspects that help the selection of the conditions to achieve the desired release profiles for a specific application. 相似文献
138.
Fine-grain MPI (FG-MPI) extends the execution model of MPI to allow for interleaved execution of multiple concurrent MPI processes inside an OS-process. It provides a runtime that is integrated into the MPICH2 middleware and uses light-weight coroutines to implement an MPI-aware scheduler. In this paper we describe the FG-MPI runtime system and discuss the main design issues in its implementation. FG-MPI enables expression of function-level parallelism, which along with a runtime scheduler, can be used to simplify MPI programming and achieve performance without adding complexity to the program. As an example, we use FG-MPI to re-structure a typical use of non-blocking communication and show that the integrated scheduler relieves the programmer from scheduling computation and communication inside the application and brings the performance part outside of the program specification into the runtime. 相似文献
139.
Maria Kalyva Jiri Orava Angeliki Siokou Martin Pavlista Tomas Wagner Spyros N. Yannopoulos 《Advanced functional materials》2013,23(16):2052-2059
Structural transitions in materials are accompanied by appreciable and exploitable changes in physical‐chemical properties. Whereas reversible optically‐driven atomistic changes in crystal‐to‐amorphous transitions are generally known and exploited in applications, the nature of the corresponding polyamorphic transitions between two structurally distinct meta‐stable amorphous phases is an unexplored theme. Direct experimental evidence is reported for the nature of the atomistic changes during fully reversible amorphous‐to‐amorphous switching between two individual states in the non‐crystalline As50Se50 films prepared by pulsed‐laser deposition and consequent changes in optical properties. Combination of surface sensitive X‐ray photoelectron spectroscopy and spectroscopic ellipsometry show that the near‐bandgap energy illumination and annealing induce reversible switching in the material's structure by local bonding rearrangements. This is accompanied by switching in refractive index between two well‐defined states. Exploiting the pluralism of distinct structural states in a disordered solid can provide new insights into the data storage in emerging optical memory and photonic applications. 相似文献
140.
Kennard Betsy D.; Clarke Greg N.; Weersing V. Robin; Asarnow Joan Rosenbaum; Shamseddeen Wael; Porta Giovanna; Berk Michele; Hughes Jennifer L.; Spirito Anthony; Emslie Graham J.; Keller Martin B.; Wagner Karen D.; Brent David A. 《Canadian Metallurgical Quarterly》2009,77(6):1033
In this report, we conducted a secondary analysis of the Treatment of SSRI-Resistant Depression in Adolescents (TORDIA) study to explore the impact of specific cognitive–behavioral therapy (CBT) treatment components on outcome. In TORDIA, 334 youths (ages 12 to 18 years) with major depressive disorder who had failed to respond to an adequate course of selective serotonin reuptake inhibitor (SSRI) medication were randomized to a medication switch (either to an alternative SSRI or venlafaxine) with or without 12 weeks of adjunctive CBT. Participants who had more than 9 CBT sessions were 2.5 times more likely to have adequate treatment response than those who had 9 or fewer sessions. CBT participants who received problem-solving and social skills treatment components, controlling for number of sessions and other confounding variables, were 2.3 and 2.6 times, respectively, more likely to have a positive response. These preliminary findings underscore the importance of receiving an adequate number of sessions to attain an adequate clinical response. Finally, social skills and problem solving may be active elements in CBT for adolescent depression and should be considered in treatment by those working with seriously depressed youths. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献