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991.
Rajiv Kumar Ashok K. Tiwari Uttara Chaturvedi G. Ravi Kumar Aditya P. Sahoo R. S. Rajmani Lovleen Saxena Shikha Saxena Sangeeta Tiwari Sudesh Kumar 《Applied biochemistry and biotechnology》2012,167(7):2005-2022
Cancer is one of the killer diseases in humans and needs alternate curative measures despite recent improvement in modern treatment modalities. Oncolytic virotherapy seems to be a promising nonconventional way to treat cancers. Newcastle disease virus (NDV), a poultry virus, is nonpathogenic to human and domestic animals and has a long history of being used in oncotherapy research in several preclinical studies. The ability of NDV to successfully infect and destroy cancer cells is dependent on the strain and the pathotype of the virus. Adaptation of viruses to heterologous hosts without losing its replicative and oncolytic potential is prerequisite for use as cancer virotherapeutics. In the present study, velogenic NDV was adapted for replication in HeLa cells, and its cytotoxic potential was evaluated by observing morphological, biochemical, and nuclear landmarks of apoptosis. Our results indicated that the NDV-induced apoptosis in HeLa cells was dependent on upregulation of TNF-related apoptosis-inducing ligand (TRAIL) and caspases activation. Different determinants of apoptosis evaluated in the present study indicated that this strain could be a promising candidate for cancer therapy in future. 相似文献
992.
A successful approach to calculating van der Waals (vdW) forces between irregular bodies is to divide the bodies into small cylindrical volume elements and integrate the vdW interactions between opposing elements. In this context it has been common to use Hamaker's expression for parallel plates to approximate the vdW interactions between the opposing elements. This present study shows that Hamaker's vdW expression for parallel plates does not accurately describe the vdW interactions for co-axial cylinders having a ratio of cylinder radius to separation distance (R/D) of 10 or less. This restricts the systems that can be simulated using this technique and explicitly excludes consideration of topographical or compositional variations at the nanoscale for surfaces that are in contact or within a few nm of contact. To address this limitation, approximate analytical expressions for nonretarded vdW forces between finite cylinders in different orientations are derived and are shown to produce a high level of agreement with forces calculated using full numerical solutions of the corresponding Hamaker's equations. The expressions developed here allow accurate calculation of vdW forces in systems where particles are in contact or within a few nm of contact with surfaces and the particles and/or surfaces have heterogeneous nanoscale morphology or composition. These calculations can be performed at comparatively low computational cost compared to the full numerical solution of Hamaker's equations. 相似文献
993.
Tetrahydropyranyl (THP) ethers have been efficiently and simply deprotected by using Silica supported sodium hydrogen sulphate (NaHSO4‐SiO2) in methanol at room temperature to regenerate the parent alcohols in high yields. 相似文献
994.
Lalithambigai K Suresh P Ravi V Prabakaran K Jaroszewicz Z Rajesh KB Anbarasan PM Pillai TV 《Optics letters》2012,37(6):999-1001
We investigate the focusing properties of a double-ring-shaped azimuthally polarized beam by a high numerical aperture (NA) lens axicon based on vector diffraction theory. We observe that our proposed system generates a sub wavelength focal hole of 0.5λ having large uniform focal depth of 48λ without any annular aperture. We also observed that the distribution of the total intensity near the focus has little variation with the degree of truncation β of the incident beam by the pupil. The authors expect such a super-long dark channel may find applications in optical, biological, and atmospheric sciences. 相似文献
995.
A series of novel α‐aminophosphonates have been prepared by one‐pot three‐component condensation in the presence of a zinc acetate (Zn(OAc)2•2H2O) catalyst at 50°C under solvent‐free conditions with excellent yields. The major advantages of the present method are high yields, a short reaction time, and solvent‐free reaction conditions. Their antimicrobial activity was evaluated, and some of them showed significant activity. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:160–165, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20765 相似文献
996.
Mukherjee B Peterson A Subramanian VR 《Chemical communications (Cambridge, England)》2012,48(18):2415-2417
Heterostructured CdS nanowires with PbS deposits forming p-n junctions have been synthesized by successive cation exchange. The method developed herein opens up the possibility of preparing a spatially distributed heterojunction-based multifunctional electrode. The (photo)electrochemical activity of the material may be chemically tuned by changing the size and density of the p type PbS nanoparticles. 相似文献
997.
Chenghui Zhang Tongxing Li Ravi P. Agarwal Martin Bohner 《Applied Mathematics Letters》2012,25(12):2058-2065
This work is concerned with the oscillation of a certain class of fourth-order nonlinear dynamic equations on time scales. A new oscillation result and an example are included. 相似文献
998.
It has recently been shown that in the heavy traffic limit, the stationary distribution of the scaled queue length process
of a Generalized Jackson Network converges to the stationary distribution of its corresponding Reflected Brownian Motion limit.
In this paper, we show that this “interchange of limits” is valid for Stochastic Fluid Networks with Lévy inputs. Furthermore,
under additional assumptions, we extend the result to show that the interchange is valid for moments of the stationary distribution
and for state-dependent routing. The results are obtained using monotonicity and sample-path arguments. 相似文献
999.
In this paper, enhanced fluorescence from a silver film coated nanosphere templated grating is presented. Initially, numerical
simulation was performed to determine the plasmon resonance wavelength by varying the thickness of the silver film on top
of a monolayer of 400 nm nanospheres. The simulation results are verified experimentally and tested for enhancing fluorescence
from fluorescein isothiocyanate whose excitation wavelength closely matches with the plasmon resonance wavelength of the substrate
with 100 nm silver film over nanosphere. The 12 times enhancement in the intensity is attributed to the local field enhancement
in addition to the excitation of surface plasmon polaritons along the surface. 相似文献
1000.
The degradation of an aqueous solution of dichlorvos, a commonly used pesticide in India, has been systematically investigated using hydrodynamic cavitation reactor. All the experiments have been carried out using a 20 ppm solution of commercially available dichlorvos. The effect of important operating parameters such as inlet pressure (over a range 3-6 bar), temperature (31 °C, 36 °C and 39 °C) and pH (natural pH = 5.7 and acidic pH = 3) on the extent of degradation has been investigated initially. It has been observed that an optimum value of pressure gives maximum degradation whereas low temperature and pH of 3 are favorable. Intensification studies have been carried out using different additives such as hydrogen peroxide, carbon tetrachloride, and Fenton’s reagent. Use of hydrogen peroxide and carbon tetrachloride resulted in the enhancement of the extent of degradation at optimized conditions but significant enhancement was obtained with the combined use of hydrodynamic cavitation and Fenton’s chemistry. The maximum extent of degradation as obtained by using a combination of hydrodynamic cavitation and Fenton’s chemistry was 91.5% in 1 h of treatment time. The present work has conclusively established that hydrodynamic cavitation in combination with Fenton’s chemistry can be effectively used for the degradation of dichlorvos. 相似文献