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排序方式: 共有1005条查询结果,搜索用时 250 毫秒
1.
Mathematical Programming - We seek tight bounds on the viable parallelism in asynchronous implementations of coordinate descent that achieves linear speedup. We focus on asynchronous coordinate... 相似文献
2.
miRNA (miR)-155 is a potential biomarker for breast cancers. We aimed at developing a nanosensor for miR-155 detection by integrating hybridization chain reaction (HCR) and silver nanoclusters (AgNCs). HCR serves as an enzyme-free and isothermal amplification method, whereas AgNCs provide a built-in fluorogenic detection probe that could simplify the downstream analysis. The two components were integrated by adding a nucleation sequence of AgNCs to the hairpin of HCR. The working principle was based on the influence of microenvironment towards the hosted AgNCs, whereby unfolding of hairpin upon HCR has manipulated the distance between the hosted AgNCs and cytosine-rich toehold region of hairpin. As such, the dominant emission of AgNCs changed from red to yellow in the absence and presence of miR-155, enabling a ratiometric measurement of miR with high sensitivity. The limit of detection (LOD) of our HCR-AgNCs nanosensor is 1.13 fM in buffered solution. We have also tested the assay in diluted serum samples, with comparable LOD of 1.58 fM obtained. This shows the great promise of our HCR-AgNCs nanosensor for clinical application. 相似文献
3.
The application of the method of multiplier ideal sheaves to effective problems in algebraic geometry is briefly discussed. Then its application to the deformational invariance of plurigenera for general compact algebraic manifolds is presented and discussed. Finally its application to the conjecture of the finite generation of the canonical ring is explored, and the use of complex algebraic geometry in complex Neumann estimates is discussed.
相似文献4.
A high-performance liquid chromatographic procedure was developed for the quantitation of homoharringtonine in plasma. Harringtonine was used as an internal standard, and 1 ml of sample was required. The single-step extraction with dichloromethane resulted in almost 100% recovery for homoharringtonine and harringtonine. Analysis was performed on a reversed-phase CN column with amperometric detection. Chromatography was completed in 12 min. At an oxidation potential of +1.0 V, the detection limit was 1 ng/ml at a signal-to-noise ratio of 2. The mean analytical recovery for homoharringtonine was 99.5%. The within-run precision and between-run precision were both less than 11%. The method is equally applicable for plasma or serum, and it has been demonstrated to be applicable for study of the pharmacokinetics of homoharringtonine in patients suffering from acute non-lymphocytic leukaemia. 相似文献
5.
6.
We prove that directly reducible lattices and selfdual subdirectly irreducible lattices of locally finite length are determined by their sublattice-lattices. As a corollary we obtain that splitting varieties are closed under the isomorphism of sublattice-lattices iff they are selfdual. A class of selfdual non-closed varieties is given too. 相似文献
7.
Paital AR Mitra T Ray D Wong WT Ribas-Ariño J Novoa JJ Ribas J Aromí G 《Chemical communications (Cambridge, England)》2005,(41):5172-5174
Based on a combined theoretical-experimental study, we propose that substituted m-phenylene ligands (m-N-Phi-N) can act as tuneable strong ferromagnetic couplers connecting Cu(II) ions; a new complex presenting that bridge with J close to +15 cm(-1) has been suggested and synthesized. 相似文献
8.
B. Király F. Tárkányi S. Takács Z. Kovács 《Journal of Radioanalytical and Nuclear Chemistry》2006,270(2):369-378
Summary Excitation functions of proton induced nuclear reactions on natural Te were investigated up to 18 MeV. Cross sections for
production of 121,123,124,126,128,130gI and 121gTe were measured. The new experimental data were compared with the results of ALICE-IPPE model calculations and with data
found in the literature and measured on natural or enriched Te targets. The new data can be effectively used for validation
of recommended cross sections of medically relevant 123I and 124I. 相似文献
9.
Shoeib T Cunje A Hopkinson AC Siu KW 《Journal of the American Society for Mass Spectrometry》2002,13(4):408-416
Collision-induced dissociation experiments on the Ag+-phenylalanine complex using several collision energies were shown to yield ten different fragment ions. Unambiguous assignment of these fragment ions were made by careful analysis of deuterium labeling experiments. The losses of H2O, CO, CO2, and AgH were commonly observed; also encountered were the losses of H2, Ag, and H. Deuterium labeling experiments and density functional calculations have been employed to probe fragmentation mechanisms that account for all experimental results. 相似文献
10.
Shi T Orlova G Guo J Bohme DK Hopkinson AC Siu KW 《Journal of the American Chemical Society》2004,126(25):7975-7980
Despite reports to the contrary, doubly charged lead monohydrate is a stable species against both proton and charge transfers. [Pb(H(2)O)](2+) has been observed as a minor product in the ligand-exchange reaction of [Pb(CH(3)CN)](2+) with H(2)O after collisional activation. Density functional theory has been used to examine reaction profiles of [Pb(H(2)O)(n)](2+) where n = 1, 2, and 3. 相似文献