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81.
This letter presents Progression‐Preserving Projection, a dimension reduction technique that finds a linear projection that maps a high‐dimensional sensor dataset into a two‐ or three‐dimensional subspace with a particularly useful property for visual exploration. As a demonstration of its effectiveness as a visual exploration and diagnostic means, we empirically evaluate the proposed technique over a dataset acquired from our own virtual‐reality‐enhanced ball‐intercepting training system designed to promote the upper extremity movement skills of individuals recovering from stroke‐related hemiparesis. 相似文献
82.
Hillman EM Amoozegar CB Wang T McCaslin AF Bouchard MB Mansfield J Levenson RM 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2011,369(1955):4620-4643
This paper provides an overview of optical imaging methods commonly applied to basic research applications. Optical imaging is well suited for non-clinical use, since it can exploit an enormous range of endogenous and exogenous forms of contrast that provide information about the structure and function of tissues ranging from single cells to entire organisms. An additional benefit of optical imaging that is often under-exploited is its ability to acquire data at high speeds; a feature that enables it to not only observe static distributions of contrast, but to probe and characterize dynamic events related to physiology, disease progression and acute interventions in real time. The benefits and limitations of in vivo optical imaging for biomedical research applications are described, followed by a perspective on future applications of optical imaging for basic research centred on a recently introduced real-time imaging technique called dynamic contrast-enhanced small animal molecular imaging (DyCE). 相似文献
83.
Kay DP Blankenship AL Coady KK Neigh AM Zwiernik MJ Millsap SD Strause K Park C Bradley P Newsted JL Jones PD Giesy JP 《Environmental science & technology》2005,39(16):5964-5974
A series of field studies were conducted to gain a better understanding of the bioaccumulation and dynamics of polychlorinated biphenyl (PCB) congeners in the aquatic food web of the Kalamazoo River flood plain. Representative species of passerine birds, mammals, fish, aquatic plants, invertebrates, and colocated sediments were collected from areas located within submerged portions of the former Trowbridge impoundment and also from areas located at an upstream reference location. In most matrixes, total concentrations of PCBs were significantly greater in the downstream study area compared to the upstream reference location. Patterns of PCB congeners varied among trophic levels due to selective bioaccumulation of more chlorinated congeners in upper trophic level organisms. There were no statistically significant differences in total PCB concentrations among sampling grids within either site or temporally among three sampling seasons between May and September. The greatest total PCB concentrations were detected in adult tree swallows (mean = 8.7 mg/kg wet weight (ww)) and fish (mean = 4.4 mg/ kg ww) collected from the former Trowbridge impoundment. Concentrations of total 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) were greatest in egg, nestling, and adult tree swallows collected from the former Trowbridge impoundment. There was not a significant correlation between concentrations of total PCBs and TEQs at either site in the mammalian or avian food webs. The relative potency of the mixture of PCBs, expressed as the ratio of TEQs to total PCBs, increased with trophic position in the avian and mammalian aquatic food webs located within the former Trowbridge impoundment. 相似文献
84.
Martina B. Sintzel Alain Merkli Cyrus Tabatabay Robert Gurny 《Drug development and industrial pharmacy》1997,23(9):857-878
A survey was made of the influence of irradiation sterilization on relevant natural, semisynthetic, and synthetic polymers used for drug carrier system. The first part of the review deals with some general aspects of irradiation treatment and its use in the sterilization of pharmaceuticals. The second part reviews the information available in the literature on polymeric biomatenals used for carriers after irradiation sterilization. The influence of irradiation sterilization has been described for polyester, poly(ortho ester), different synthetic hydrogels, silicone derivatives, cellulose-derivatives, hyaluronic acid, different glucosides, collagen, and gelatine. Also, some limitations concerning the use of high-energy radiations for sterilization are given. 相似文献
85.
Dr.-Ing. Václav Cyrus 《Forschung im Ingenieurwesen》1996,62(3):58-64
Three blading designs of high pressure ratio axial flow fan with hub/tip ratio of 0.7 were carried out with the use of compressor
design technology. The flow coefficient and/or pressure coefficient moved in the range of 0.4 to 0.65 and/or 0.65 to 0.85.
In the design computations own secondary losses data were applied. The blading tests proved maximum efficiency over 90% in
all variants. The measured values of fan stage pressure coefficient were higher than the theoretical ones at design conditions.
It consists in a lower rotor deviation angles in contrast to the design. Therefore some ampirical dependencies were derived. 相似文献
86.
Arvind Pattamatta Cyrus K. Madnia 《International Journal of Heat and Mass Transfer》2009,52(3-4):860-869
Bi2Te3–Sb2Te3 nanostructures are gaining importance for use in thermoelectric applications following the finding that the Bi2Te3–Sb2Te3 superlattice exhibits a figure of merit, ZT = 2.4, which is higher than conventional thermoelectric materials. In this paper, thermal transport in the cross-plane direction for Bi2Te3–Sb2Te3 nanostructures is simulated using the Boltzmann transport equation (BTE) for phonon intensity. The phonon group velocity, specific heat, and relaxation time are calculated based on phonon dispersion model. The interfaces are modeled using a combination of diffuse mismatch model (DMM), and the elastic acoustic mismatch model (AMM). The thermal conductivity for the Bi2Te3–Sb2Te3 superlattice is compared with the experimental data, and the best match is obtained for specularity parameter, p, of 0.9. The present model is extended to solve for thermal transport in 2-D nanowire composite in which Sb2Te3 wires are embedded in a host material of Bi2Te3. Unlike in bulk composites, the results show a strong dependence of thermal conductivity, temperature, and heat flux on the wire size, wire atomic percentage, and interface specularity parameter. The thermal conductivity of the nanowire is found to be in the range of 0.034–0.74 depending on the atomic percentage and the value of p. 相似文献
87.
Zhan Hangjun; Liu Beishan; Reid Scott W.; Aoki Kenneth H.; Li Cuiwei; Syed Rashid S.; Karkaria Cyrus; Koe Gary; Sitney Karen; Hayenga Kirk; Mistry Firoz; Savel Laura; Dreyer Mark; Katz Bradley A.; Schreurs Jolanda; Matthews David J.; Cheetham Janet C.; Egrie Joan; Giebel Lutz B.; Stroud Robert M. 《Protein engineering, design & selection : PEDS》1999,12(6):505-513
The extracellular ligand-binding domain (EPObp) of the humanEPO receptor (EPOR) was expressed both in CHO (Chinese HamsterOvary) cells and in Pichia pastoris. The CHO and yeast expressedreceptors showed identical affinity for EPO binding. Expressionlevels in P.pastoris were significantly higher, favoring itsuse as an expression and scale-up production system. Incubationof EPO with a fourfold molar excess of receptor at high proteinconcentrations yielded stable EPOEPObp complexes. Quantificationof EPO and EPObp in the complex yielded a molar ratio of oneEPO molecule to two receptor molecules. Residues that are responsiblefor EPOR glycosylation and isomerization in Pichia were identifiedand eliminated by site-specific mutagenesis. A thiol modificationwas identified and a method was developed to remove the modifiedspecies from EPObp. EPObp was complexed with erythropoietin(EPO) and purified. The complex crystallized in two crystalforms that diffracted to 2.8 and 1.9 Å respectively. (Form1 and form 2 crystals were independently obtained at AxyS Pharmaceuticals,Inc. and Amgen, Inc. respectively.) Both contained one complexper asymmetric unit with a stoichiometry of two EPObps to oneEPO. 相似文献
88.
Evaluation of Heat Transfer Augmentation in a Nanofluid-Cooled Microchannel Heat Sink 总被引:1,自引:0,他引:1
Present investigation deals with appraising heat transfer enhancement of single phase microchannel heat sink (MCHS) by ultra fine Cu particle incorporation in base coolant fluid. The particle diameter is of nanometer size and base fluid in combination of nanoparticles is called nanofluid. Governing equations for fluid flow and heat transfer are based on well established “porous medium model” and accordingly, modified Darcy equation and two-equation model are employed. Appropriate equations for both fluid flow and heat transfer are derived and cast into dimensionless form. Velocity profile is obtained analytically and in order to solve conjugate heat transfer problem a combined analytical–numerical approach is employed. For heat transfer analysis, thermal dispersion model is adopted and latest proposed model for effective thermal conductivity – which considers the salient effect of interfacial shells between particles and base fluid – is integrated into model. The effects of dispersed particles concentration, thermal dispersion coefficient and Reynolds number are investigated on thermal fields and on thermal performance of MCHS. Additionally, the impact of turbulent heat transfer on heat transfer enhancement is considered. 相似文献
89.
Young R. Kim Ramesh R. Yettella Young S. Kim Cyrus K. Hah Cherl W. Park Yeong L. Ha Jeong O. Kim David B. Min 《International Journal of Food Science & Technology》2011,46(12):2538-2543
The capacity of oyster mushroom (Pleurotus ostreatus) mycelium to produce meaty flavour compounds in the presence of amino acids and sugars was studied. The submerged liquid culture of P. ostreatus mycelium along with base medium made of defatted soybean powder, sucrose, potassium phosphate, and magnesium sulphate was incubated for 3 days at 25 °C. Cysteine, glutamine, or methionine and fructose, galactose, ribose, or xylose were added to the base medium to study the effect of amino acids and sugars on meaty flavour formation by trained panelists. The flavour compounds were isolated and identified by GC–MS and GC retention time of authentic compounds. The base medium required P. ostreatus, cysteine, ribose, and heat treatment to produce meaty flavour. The sulphur containing heterocyclic compounds such as 2,5‐diethylthiophene, 2‐formyl‐5‐methylthiophene, 3‐ethyl‐2‐formylthiophene, and dimethylformyl thiophene were responsible for meaty flavour. These compounds were formed by non‐enzymatic browning reaction between ribose and cysteine during heat treatment. 相似文献
90.
A Road Network Embedding Technique for K-Nearest Neighbor Search in Moving Object Databases 总被引:1,自引:0,他引:1
A very important class of queries in GIS applications is the class of K-nearest neighbor queries. Most of the current studies on the K-nearest neighbor queries utilize spatial index structures and hence are based on the Euclidean distances between the points. In real-world road networks, however, the shortest distance between two points depends on the actual path connecting the points and cannot be computed accurately using one of the Minkowski metrics. Thus, the Euclidean distance may not properly approximate the real distance. In this paper, we apply an embedding technique to transform a road network to a high dimensional space in order to utilize computationally simple Minkowski metrics for distance measurement. Subsequently, we extend our approach to dynamically transform new points into the embedding space. Finally, we propose an efficient technique that can find the actual shortest path between two points in the original road network using only the embedding space. Our empirical experiments indicate that the Chessboard distance metric (L) in the embedding space preserves the ordering of the distances between a point and its neighbors more precisely as compared to the Euclidean distance in the original road network. 相似文献