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251.
Samsung Card Lending Model (SCLM) analyzes cash flow in individual accounts and measures the level of company-wide risk. Serving as a risk and portfolio management model in the consumer lending business, the main features of SCLM are as follows. Default ratios such as intrinsic balance default probability and annual default ratio are computed using the past, present, and future cash flows of accounts. The provision is shown as the total sum of write-offs. The size of capital required is determined by default probability distribution. The price for new accounts is quoted based on cash flow simulations reflecting future business environments. SCLM has shown good performance in Samsung card consumer lending business since the Korean credit card crisis of 2003. 相似文献
252.
A scalable synthetic route towards a chiral 2,2,6-trisubstituted chiral morpholine, which is a known opioid antagonist, was developed. The synthetic route involves incorporating an aryl group via Suzuki-Miyaura coupling and stereoselective hydroalkoxylation catalyzed by trifluoromethanesulfonic acid. Late stage incorporation of both the aryl and N-alkyl groups make this route suitable for further SAR studies on this molecule. 相似文献
253.
Hyungjin Huh 《Letters in Mathematical Physics》2010,91(1):29-44
We study initial value problems for Chern–Simons–Proca–Higgs equations. We prove that the Cauchy problem is locally well posed
under the Lorentz gauge condition. In the case of repulsive potential, the global existence of the solution is proved using
the covariant version of the Brezis–Gallouet inequality. In the case of attractive potential, we show that for initial data
having negative energy, the solution has a finite time singularity. 相似文献
254.
Proton beam is useful to target tumor tissue sparing normal cells by allowing precise dose only into tumor cells. However, the cellular and molecular mechanisms by which proton beam induces tumor cell death are still undefined. We irradiated three different tumor cells (LLC, HepG2, and Molt-4) with low energy proton beam (35 MeV) with spread out Bragg peak (SOBP) in vitro, and investigated cell death by MTT or CCK-8 assay at 24 h after irradiation. LLC and HepG2 cells were sensitive to proton beam at over 10 Gy to induce apoptosis whereas Molt-4 showed rather low sensitivity. Relative biological effectiveness (RBE) values for the death rate relative to gamma-ray were ranged from 1.1 to 2.3 in LLC and HepG2 but from 0.3 to 0.7 in Molt-4 at 11 d after irradiation by colony formation assay. The typical apoptotic nuclear DNA morphological pattern was observed by staining with 4'-6-diamidino-2-phenylindole (DAPI). Tiny fragmented DNA was observed in HepG2 but not in Molt-4 by the treatment of proton in apoptotic DNA fragment assay. By FACS analysis after stained with FITC-Annexin-V, early as well as median apoptotic fractions were clearly increased by proton treatment. Proton beam-irradiated tumor cells induced a cleavage of poly (ADP-ribose) polymerase-1 (PARP-1) and procaspases-3 and -9. Activity of caspases was highly enhanced after proton beam irradiation. Reactive oxygen species (ROS) were significantly increased and N-acetyl cysteine pretreatment restored the apoptotic cell death induced by proton beam. Furthermore, p38 and JNK but not ERK were activated by proton and dominant negative mutants of p38 and JNK revived proton-induced apoptosis, suggesting that p38 and JNK pathway may be activated through ROS to activate apoptosis. In conclusion, our data clearly showed that single treatment of low energy proton beam with SOBP increased ROS and induced cell death of solid tumor cells (LLC and HepG2) in an apoptotic cell death program by the induction of caspases activities. 相似文献
255.
Krishnan Giribabu Seo Yeong Oh Ranganathan Suresh Sivakumar Praveen Kumar Ramadoss Manigandan Settu Munusamy Govindhan Gnanamoorthy Jun Yeong Kim Yun Suk Huh Vengidusamy Narayanan 《Mikrochimica acta》2016,183(8):2421-2430
We describe the preparation of a nanohybrid consisting of nitrogen doped reduced graphene oxide and CuS nanoparticles (N-rGO/CuS) by in-situ microwave irradiation at weight ratios of 25/75, 50/50, and 75/25. The resulting nanohybrids were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, FTIR, spectroscopy, scanning electron and transmission electron microscopy, electrochemically by cyclic voltammetry and electrochemical impedance analysis. It is shown that the CuS nanoparticles are evenly decorated onto the N-rGO surface. The nanohybrids was placed on glassy carbon electrode (GCE) where they showed electro-reductive activity towards picric acid, typically at working voltages between ?0.2 and ?0.8 V (vs. SCE). Effects of pH value and scan rate were evaluated, and it is shown that two electrons are involved in electro-reduction. The detection limits of the GCE modified with various N-rGO/CuS hybrids (with 25/75, 50/50, and 75/25 wt%) are 6.2, 3.2, and 0.069 μM respectively. The method demonstrates its applicability in sensing of picric acid with good reproducibility. 相似文献
256.
Stretching DNA has emerged as a vital process for studying the physical and biological properties of these molecules. Over
the past decade, there has been increasing research interest in utilizing nanoscale fluidic channels to confine and stretch
single DNA molecules. Nanofabricated systems for linearizing DNA have revealed new and important insights into the conformation
changes of DNA molecules. They also have emerged as innovative techniques for efficiently separating DNA molecules based on
size and for physically mapping genetic information along the genome. This review describes physical theories of DNA linearization,
current DNA stretching techniques based on nanofabricated channels, and breakthroughs resulting from the use of nanofluidic
channels for DNA linearization. 相似文献
257.
J.Y. Huh C.S. Lee Y.K. Kwon J.Y. Kim Y. Gono T. Morikawa H. Watanabe M. Shibata S. Motomura T. Tsutsumi T. Fukuchi T. Kishida E. Ideguchi X.H. Zhou A. Odahara S. Kubono J.H. Ha M.K. Cheoun C. Lee J.C. Kim C.-B. Moon S.J. Chae Y.K. Kim J.S. Chai 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):11-14
High-spin states of 155Gd were populated by using the 154Sm(α,3nγ)155Gd reaction at E
α= 33 MeV. γ-γ coincidence, E
γ singles, excitation function, and the DCO ratios were measured. we have identified three intermediate bands with ΔI= 2 feeding the positive yrast band. The bands are interpreted as such candidate bands that are mixed with the negative-parity
ground state band. This observation can provide a plausible explanation for unusually large population of the positive-parity
yrast band observed in a recent Coulomb excitation.
Received: 2 November 1999 相似文献
258.
Microstructural and electrical properties of potentiostatically electrodeposited ZnO thin films from an aqueous bath were investigated after annealing at different temperatures in Ar and 5% H2/Ar atmospheres. It is confirmed that the bandgap energy of ZnO thin films decreased with annealing from 3.42 to 3.27-3.29 eV by calculating the wavelength of the absorption region. The annealing at temperatures as low as 200 °C decreased the sheet resistance of ZnO thin films because of the extinction of Zn(OH)2 in the atmosphere. In addition, the sheet resistance of ZnO thin films decreased by annealing in a 5% H2 atmosphere, which caused an increase of carrier concentration by hydrogen reduction. 相似文献
259.
Cross‐linked Iron Oxide Nanoparticles for Therapeutic Engineering and in Vivo Monitoring of Mesenchymal Stem Cells in Cerebral Ischemia Model 下载免费PDF全文