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21.
McMillan GP Saunders G Hanson TE 《The Journal of the Acoustical Society of America》2011,129(6):EL229-EL235
Horizontal localization experiments are used to evaluate the listener's ability to locate the position of a sound source, and determine how signal characteristics affect this ability. These experiments generate circular, bimodal, and repeated data that are challenging to statistically analyze. A two-part mixture of wrapped Cauchys is proposed for these data, with the effects of signal type and position on localization bias, precision, and front-back confusion modeled using regression. The model is illustrated using mid- (1.0-2.0 kHz) and high- (3.0-6.0 kHz) frequency narrow band noises localization collected among ten normal hearing listeners. 相似文献
22.
Anna M. Waldron Carl A. Batt Clarissa S. Lui 《Journal of nanoparticle research》2011,13(12):6291-6295
Public engagement in nanotechnology media products can lead to a greater interest in understanding of nanotechnology. A study
was undertaken to determine middle school student engagement in Nanooze, a magazine featuring nanotechnology research that has been developed for a young adult audience. Teachers at 116 Detroit
middle schools distributed two issues of the magazine to their students, and surveys were collected from 870 students after
reading the magazines. Results suggest that the majority of students liked reading the magazine and learned something about
nanotechnology. Engagement in nanotechnology led to understanding of nanotechnology. The Nanooze magazine was an effective medium for engaging middle school students in learning about nanotechnology. 相似文献
23.
Markov chains and mean-field analysis are powerful tools and widely used for performance analysis in large-scale computer and communication systems. In this paper, we consider the application of Markov modeling and mean-field analysis to solid-state drives (SSDs). SSDs are now widely deployed in mobiles, desktops, and data centers due to their high I/O performance and low energy consumption. In particular, we focus on characterizing the performance–durability tradeoff of garbage collection (GC) algorithms in SSDs. Specifically, we first develop a stochastic Markov chain model to capture the I/O dynamics of large-scale SSDs, then adapt mean-field analysis to derive the asymptotic steady state, based on which we are able to easily analyze the performance–durability tradeoff of a large family of GC algorithms. We further prove the model convergence and generalize the model for all types of workload. Inspired by this model, we also propose a randomized greedy algorithm (RGA) which has a single tunable parameter to trade between performance and durability. Using trace-driven simulation on DiskSim with SSD add-ons, we demonstrate how RGA can be parameterized to realize the performance–durability tradeoff. 相似文献
24.
25.
Roberto Laridondo Lui Daniel Rodrigues Blanco Vladimir Pavan Margarido Orlando Moreira Filho 《Micron (Oxford, England : 1993)》2009,40(5-6):552-559
B chromosomes are considered additional and non-essential; they likely originate from A chromosomes and follow a distinct evolution. In fish, approximately half of the Neotropical species with B chromosomes are Characiformes and 35% are Siluriformes. There has been no report of B chromosomes in Auchenipteridae until this moment. B chromosomes found in a population of Parauchenipterus galeatus from the São Francisco River basin in the state of Minas Gerais (Brazil) were small, metacentric, totally heterochromatic and exhibited intra-individual and inter-individual variation. The diploid number was 58 chromosomes (22 metacentric, 16 submetacentric, 12 subtelocentric and 8 acrocentric). The nucleolar organizing regions were simple and the heterochromatin intercalated in the ribosomal sites, characterized by CMA3 and DAPI fluorochromes, was of a GC-rich constitution. The 5S rDNA genes were located in an intercalary position in only one chromosome pair. An hypothesis about the origin of the B chromosomes in P. galeatus and a review on B chromosomes in catfish are also presented in this study. 相似文献
26.
Rongchuan Lui Qijie Yan Ya Zhai Haihua QI Yuanfu Hsia J. Jiang U. Gonser 《Hyperfine Interactions》1992,69(1-4):847-850
Solid-solid surface adsorption of Eu2O3 on anorphous Al2O3 have been investigated by the Mössbauer effect, X-ray diffraction analysis (XRD.) and Laser Raman Spectroscopy (LRS). The results of these studies indicate that the structure of EU2O3 dispersed onto the support surface depends on the structure of support and that there is an inductive effect of the support on the structure of the Eu2O3. 相似文献
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28.
Conventional analyses of frameworks are usually carried out without considering the effect of panel zone deformation on frame behavior. As a result, center-to-center distances rather than clear spans are used for the lengths of the members. As is evident from experimental studies, the effect of panel zone deformation has a pronounced influence on frame behavior. In particular, the strength and drift of the frame will be affected if panel zone deformation is taken into consideration in the analysis. In this paper, various deformation modes of the panel zone are identified. A simple model which can be used to represent all these modes is then presented. The validity of this model is established by comparison with experiments on joint subassemblages. Finally, a two-bar frame with different behavioral joint models is analyzed numerically to demonstrate the importance of using realistic models in frame analysis. 相似文献
29.
Serhan CN Fredman G Yang R Karamnov S Belayev LS Bazan NG Zhu M Winkler JW Petasis NA 《Chemistry & biology》2011,18(8):976-987
Endogenous mechanisms in the resolution of acute inflammation are of interest because excessive inflammation underlies many pathologic abnormalities. We report an aspirin-triggered DHA metabolome that biosynthesizes a potent product in inflammatory exudates and human leukocytes, namely aspirin-triggered Neuroprotectin D1/Protectin D1 [AT-(NPD1/PD1)]. The complete stereochemistry of AT-(NPD1/PD1) proved to be 10R,17R-dihydroxydocosa-4Z,7Z,11E,13E,15Z,19Z-hexaenoic acid. The chirality of hydroxyl groups and geometry of the conjugated triene system essential for bioactivity were established by matching biological materials with stereochemically pure isomers prepared by organic synthesis. AT-(NPD1/PD1) reduced neutrophil (PMN) recruitment in murine peritonitis in a dose-dependent fashion whereby neither a Δ(15)-trans-isomer nor DHA was effective. With human cells, AT-(NPD1/PD1) decreased transendothelial PMN migration as well as enhanced efferocytosis of apoptotic human PMN by macrophages. These results indicate that AT-(NPD1/PD1) is a potent anti-inflammatory proresolving molecule. 相似文献
30.
Julio Gutierrez Rodney Eisenberg Gabrielle Herrensmith Thomas Tobin Tonglei Li Sihui Long 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(8):o310-o314
The structures of orthorhombic (E)‐4‐(2‐{[amino(iminio)methyl]amino}vinyl)‐3,5‐dichlorophenolate dihydrate, C8H8Cl2N4O·2H2O, (I), triclinic (E)‐4‐(2‐{[amino(iminio)methyl]amino}vinyl)‐3,5‐dichlorophenolate methanol disolvate, C8H8Cl2N4O·2CH4O, (II), and orthorhombic (E)‐amino[(2,6‐dichloro‐4‐hydroxystyryl)amino]methaniminium acetate, C8H9Cl2N4O+·C2H3O2−, (III), all crystallize with one formula unit in the asymmetric unit, with the molecule in an E configuration and the phenol H atom transferred to the guanidine N atom. Although the molecules of the title compounds form extended chains via hydrogen bonding in all three forms, owing to the presence of different solvent molecules, those chains are connected differently in the individual forms. In (II), the molecules are all coplanar, while in (I) and (III), adjacent molecules are tilted relative to one another to varying degrees. Also, because of the variation in hydrogen‐bond‐formation ability of the solvents, the hydrogen‐bonding arrangements vary in the three forms. 相似文献