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41.
Fully integrated lab-on-a-disc for simultaneous analysis of biochemistry and immunoassay from whole blood 总被引:2,自引:0,他引:2
We report a fully integrated device that can perform both multiple biochemical analysis and sandwich type immunoassay simultaneously on a disc. The whole blood is applied directly to the disposable "lab-on-a-disc" containing different kinds of freeze-dried reagents for the blood chemistry analysis as well as reagents required for the immunoassay. The concentrations of different kinds of analytes are reported within 22 min by simply inserting a disc to a portable device. Using the innovative laser irradiated ferrowax microvalves together with the centrifugal microfluidics, the total process of plasma separation, metering, mixing, incubation, washing, and detection is fully automated. The analyzer is equipped with an optical detection module to measure absorbances at 10 different wavelengths to accommodate the various kinds of reaction protocols. Compared to the conventional blood analysis done in clinical laboratories, it is advantageous for point-of-care applications because it requires a smaller amount of blood (350 μL vs. 3 mL), takes less time (22 min vs. several days), does not require specially trained operators or expensive instruments to run biochemical analysis and immunoassay separately. 相似文献
42.
Wee Liang Gan 《Advances in Mathematics》2006,205(2):599-630
We construct reflection functors on categories of modules over deformed wreath products of the preprojective algebra of a quiver. These functors give equivalences of categories associated to generic parameters which are in the same orbit under the Weyl group action. We give applications to the representation theory of symplectic reflection algebras of wreath product groups. 相似文献
43.
Ahmed F. Ghoniem Sungbae Park Adam Wachsman Anuradha Annaswamy Daehyun Wee H. Murat Altay 《Proceedings of the Combustion Institute》2005,30(2):1783-1790
Combustion dynamics leading to thermoacoustic instability in a rearward-facing step stabilized premixed flame is experimentally examined with the objective of investigating the fluid dynamic mechanism that drives heat release rate fluctuations, and how it couples with the acoustic field. The field is probed visually, using linear photodiode arrays that capture the spatiotemporal distribution of CH* and OH*; an equivalence ratio monitor; and a number of pressure sensors. Results show resonance between the acoustic quarter wave mode of the combustion tunnel and a fluid dynamic mode of the wake. Under unstable conditions, the flame is convoluted around a large vortex that extends several step heights downstream. During a typical cycle, while the velocity is decreasing, the vortex grows, and the flame extends downstream around its outer edge. As the velocity reaches its minimum, becoming mostly negative, the vortex reaches its maximum size, and the flame collides with the upper wall; its leading edge folds, trapping reactants pockets, and its trailing edge propagates far upstream of the step. In the next phase, while the velocity is increasing, the heat release grows rapidly as trapped reactant’ pockets are consumed by flames converging towards their centers, and the upstream flame is dislodged back downstream. The heat release rate reaches its maximum halfway into the velocity rise period, leading the maximum velocity by about 90°. In this quarter-wave mode, the pressure leads the velocity by 90° as well, that is, it is in phase with the heat release rate. Numerical modeling results support this mechanism. Equivalence ratio contribution to the instability mechanism is shown to be minor, i.e., heat release dynamics are governed by the cyclical formation of the wake vortex and its interaction with the flame. 相似文献
44.
F.C. Cheong C.H. Sow A.T.S. Wee P. Shao A.A. Bettiol J.A. van Kan F. Watt 《Applied physics. B, Lasers and optics》2006,83(1):121-125
We report the transport, funnelling and dynamic sorting of colloidal microspheres in an aqueous suspension using line optical
tweezers with asymmetrical intensity profiles. The line tweezers readily trapped and propelled the microspheres along the
length of the line tweezers. Using this simple technique, transporting and funnelling of microspheres within a microscopic
region were demonstrated. To illustrate the dynamic particle-sorting capability of the line tweezers, a binary colloidal system
comprising of microspheres with diameters of 1.1 μm and 3.2 μm were driven past the line tweezers by electrophoresis. As the
optical trapping force is dependent on the size of the microspheres, the line tweezers was able to change the path of the
larger spheres while exerting little influence on the smaller spheres thus sorting the two types of microspheres. At optimized
laser power and flow rate of microspheres, sorting efficiency greater than 90% has been achieved.
PACS 42.15.Eq; 87.80.Cc; 87.80.Fe; 82.70.Dd 相似文献
45.
M. Ebihara Y. S. Chung H. M. Dung J. H. Moon B. -F. Ni T. Otoshi Y. Oura F. L. Santos F. Sasajima Sutisna B. S. Wee W. Wimolwattanapun A. K. B. H. Wood 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):463-467
Air particulate matter (APM) samples (PM2.5 and PM10–2.5) were collected at 13 sampling points in 8 Asian countries and their chemical compositions were determined by using neutron
activation analysis (NAA) with the k
0-standardization method in addition to conventional comparative method of NAA. Analytical data showed that mass concentration
and elemental composition of the APM collected are variable in terms of time and space, and are related to the characteristics
of the sampling sites concerned. NAA was proved to be highly effective for the regional characterization of APM in chemical
composition. 相似文献
46.
Ang WH Khalaila I Allardyce CS Juillerat-Jeanneret L Dyson PJ 《Journal of the American Chemical Society》2005,127(5):1382-1383
A rationally designed Pt(IV) anticancer compound is described, employing the novel concept of tethering an inhibitor of glutathione-S-transferase, an enzyme associated with Pt-based drug-resistance, to cisplatin. Its enzyme inhibition activity, investigated using spectrophotometric and mass spectrometry-based techniques, and cytotoxic profile in resistant cancer cells are described. 相似文献
47.
Chen W Zhang HL Xu H Tok ES Loh KP Wee AT 《The journal of physical chemistry. B》2006,110(43):21873-21881
A SiC nanomesh is used as a nanotemplate to direct the epitaxy of C60 molecules. The epitaxial growth of C60 molecules on SiC nanomesh at room temperature is investigated by in situ scanning tunneling microscopy, revealing a typical Stranski-Krastanov mode (i.e., for the first one or two monolayers, it is a layer-by-layer growth or 2-D nucleation mode; at higher thicknesses, it changes to island growth or a 3-D nucleation mode). At submonolayer (0.04 and 0.2 ML) coverage, C60 molecules tend to aggregate to form single-layer C60 islands that mainly decorate terrace edges, leaving the uncovered SiC nanomesh almost free of C60 molecules. At 1 ML C60 coverage, a complete wetting layer of hexagonally close-packed C60 molecules forms on top of the SiC nanomesh. At higher coverage from 4.5 ML onward, the C60 stacking adopts a (111) oriented face-centered-cubic (fcc) structure. Strong bright and dim molecular contrasts have been observed on the first layer of C60 molecules, which are proposed to originate from electronic effects in a single-layer C60 island or the different coupling of C60 molecules to SiC nanomesh. These STM molecular contrast patterns completely disappear on the second and all the subsequent C60 layers. It is also found that the nanomesh can be fully recovered by annealing the C60/SiC nanomesh sample at 200 degrees C for 20 min. 相似文献
48.
Herng TS Qi DC Berlijn T Yi JB Yang KS Dai Y Feng YP Santoso I Sánchez-Hanke C Gao XY Wee AT Ku W Ding J Rusydi A 《Physical review letters》2010,105(20):207201
We report direct evidence of room-temperature ferromagnetic ordering in O-deficient ZnO:Cu films by using soft x-ray magnetic circular dichroism and x-ray absorption. Our measurements have revealed unambiguously two distinct features of Cu atoms associated with (i) magnetically ordered Cu ions present only in the oxygen-deficient samples and (ii) magnetically disordered regular Cu2+ ions present in all the samples. We find that a sufficient amount of both oxygen vacancies (V(O)) and Cu impurities is essential to the observed ferromagnetism, and a non-negligible portion of Cu impurities is uninvolved in the magnetic order. Based on first-principles calculations, we propose a microscopic "indirect double-exchange" model, in which alignments of localized large moments of Cu in the vicinity of the V(O) are mediated by the large-sized vacancy orbitals. 相似文献
49.
The electron transfer dynamics of oligo(p-phenylene-ethynylene) (OPE) SAM on Au(111) was studied by resonant photoemission spectroscopy. The ultrafast electron transfer from OPE molecules to Au substrate was clearly observed. The time scale for this charge transfer is much less than 6 fs, the core-hole lifetime for C 1s. This strongly suggests that there is an intense interfacial electronic coupling between OPE molecules and the Au substrate. 相似文献
50.
We analyze an immersed interface finite element method based on linear polynomials on noninterface triangular elements and
piecewise linear polynomials on interface triangular elements. The flux jump condition is weakly enforced on the smooth interface.
Optimal error estimates are derived in the broken H
1-norm and L
2-norm. 相似文献