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91.
In this paper, we propose a novel classification framework using single feature kernel matrix. Different from the traditional kernel matrices which make use of the whole features of samples to build the kernel matrix, this research uses features of the same dimension of any two samples to build a sub-kernel matrix and sums up all the sub-kernel matrices to get the single feature kernel matrix. We also use single feature kernel matrix to build a new SVM classifier, and adapt SMO (Sequential Minimal Optimization) algorithm to solve the problem of SVM classifier. The results of the experiments on several artificial datasets and some challenging public cancer datasets display the classification performance of the algorithm. The comparisons between our algorithm and L2-norm SVM on the cancer datasets demonstrate that the accuracy of our algorithm is higher, and the number of support vectors selected is fewer, indicating that our proposed framework is a more practical approach. 相似文献
92.
Shouyu Wang Liang Xue Hailong Li Jiancheng Lai Yang Song Zhenhua Li 《Applied physics. B, Lasers and optics》2014,116(1):235-239
Based on interferometric microscopy, we develop a quantitative interferometric microscopic cytometer with expanded principal component analysis (PCA) phase retrieval method to obtain phase distributions of numerous biological samples with spatial resolution ~1.5 μm. The expanded PCA method realizes high-speed phase imaging from multiple microscopic interferograms captured by CCD camera when the biological samples are scanned in the field of view. This method is a time-domain algorithm which calculates faster than traditional frequency-domain algorithms and overcomes drawbacks induced by fast Fourier transform. The potential of this phase detecting system for studying biological systems is demonstrated with simulations and phase measurement of red blood cells in experiments. 相似文献
93.
Hailong Yu Xiaolin Wang Pu Zhou Xiaojun Xu Jinbao Chen 《Applied physics. B, Lasers and optics》2014,117(1):305-309
We experimentally demonstrate cascaded Raman scattering continuum generation at 1.0–1.3 μm with pulse energy of 47 nJ by utilizing a commercially available all-normal-dispersion single-mode fiber (SMF) with a low threshold pump power. We achieve passively mode-locked all-fiber lasing by nonlinear polarization rotation technique. Continuous Raman gain is obtained by the same SMF in every roundtrip because of the ring-cavity configuration, which makes it possible to achieve high-order Raman Stokes waves by a short fiber length. Limited by the pump power, the maximum output average power and peak power are 87.4 and 339 mW, but it has great potential to be improved. These make it an ideal continuum source for many applications, such as optical coherence tomography. 相似文献
94.
95.
Lu H Wang J Liu C Ratcliffe CI Becker U Kumar R Ripmeester J 《Journal of the American Chemical Society》2012,134(22):9160-9162
Experiments were carried out by reacting H(2) gas with N(2) hydrate at a temperature of 243 K and a pressure of 15 MPa. The characterizations of the reaction products indicated that multiple H(2) molecules can be loaded into both large and small cages of structure II clathrate hydrates. The realization of multiple H(2) occupancy of hydrate cages under moderate conditions not only brings new insights into hydrogen clathrates but also refreshes the perspective of clathrate hydrates as hydrogen storage media. 相似文献
96.
Zhao J Li P Wu C Chen H Ai W Sun R Ren H Larock RC Shi F 《Organic & biomolecular chemistry》2012,10(9):1922-1930
The aryne [3 + 2] cycloaddition process with pyridinium imides breaks the aromaticity of the pyridine ring. By equipping the imide nitrogen with a sulfonyl group, the intermediate readily eliminates a sulfinate anion to restore the aromaticity, leading to the formation of pyrido[1,2-b]indazoles. The scope and limitation of this reaction are discussed. As an extension of this chemistry, N-tosylisoquinolinium imides, generated in situ from N'-(2-alkynylbenzylidene)-tosylhydrazides via an AgOTf-catalyzed 6-endo-dig electrophilic cyclization, readily undergo aryne [3 + 2] cycloaddition to afford indazolo[3,2-a]-isoquinolines in the same pot, offering a highly efficient route to these potential anticancer agents. 相似文献
97.
We develop a novel single fluorophore-labeled double-stranded oligonucleotide (OND) probe for rapid, nanostructure-free, fluorescence-enhanced
nucleic acid detection for the first time. We further demonstrate such probe is able to well discriminate single-base mutation
in nucleic acid. The design takes advantage of an inherent quenching ability of guanine bases. The short strand of the probe
is designed with an end-labeled fluorophore that is placed adjacent to two guanines as the quencher located on the long opposite
strand, resulting in great quenching of dye fluorescence. In the presence of a target complementary to the long strand of
the probe, a competitive strand-displacement reaction occurs and the long strand forms a more stable duplex with the target,
resulting in the two strands of the probe being separated from each other. As a consequence of this displacement, the fluorophore
and the quencher are no longer in close proximity and dye fluorescence increases, signaling the presence of target. 相似文献
98.
We report on the lasing characteristics of a two-color InAs/InP quantum dots(QDs)laser at a low tem-perature.Two lasing peaks with a tunable gap are simultaneously observed.At a low temperature of 80 K,a tunable range greater than a 20-nm wavelength is demonstrated by varying the injection current from 30 to 500 mA.Under a special condition,we even observe three lasing peaks,which are in contrast to those observed at room temperature.The temperature coefficient of the lasing wavelength was obtained for the two colors in the 80?280 K temperature range,which is lower than that of the reference quantum well(QW)laser working in the same wavelength region. 相似文献
99.
Li H Li D Liu J Qin Y Ren J Xu S Liu Y Mayer D Wang E 《Chemical communications (Cambridge, England)》2012,48(20):2594-2596
Signal amplification originating from electrochemical current rectifier (ECR) was firstly applied to construct a cytosensor for rapid and non-invasive detection of folate receptor-rich cancer cells with high sensitivity. It exhibits a broad linear range with a detection limit as low as 10 cells mL(-1) even in the presence of a large number of normal cells. 相似文献
100.
Correlation between molecular structures and slow relaxation of magnetization of three mixed (phthalocyaninato)(porphyrinato) dysprosium(III) double-deckers clearly reveals the effect of the sandwich-type molecular structure, in particular the twist angle, on the quantum tunneling (QT) at zero dc field of these complexes, providing the first direct evidence to the theoretical inference. 相似文献