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51.
We obtain an exact solution for the Einstein’s equations with cosmological constant coupled to a scalar, static particle in static, “spherically” symmetric background in (2+1)-dimensions. 相似文献
52.
Enhanced methods of drug monitoring are required to support the individualization of therapeutic drug dosing. Clozapine is one of the most important medications for managing schizophrenia, and timely measurement of serum clozapine levels has been identified as a barrier to the broader use of clozapine. For the first time, reduced graphene oxide nanocomposites were used to construct an electrochemical clozapine (Clz) sensor. The Reduced graphene oxide (Rego) nanocomposites were synthesized and characterized by using X-Ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) techniques. The Clz sensing electrode was fabricated by drop coating of Rego nanocomposites suspension and Nafion solution on the pencil graphite electrode, respectively. The electrochemical behavior and influence of various physicochemical parameters of sensing electrodes were investigated by using cyclic voltammetry (CV) and differential voltammetry (DPV) techniques. The designed sensor displayed decent linear range, detection limit, reproducibility, and reusability results. Under optimum experimental parameters a linear dynamic range of 0.05–10 μM clozapine was observed with actual detection limit of 50 nM. Furthermore, the designed sensing electrode was used to measure the amount of Clz in real samples. 相似文献
53.
Simge Balaban Tutku Beduk Ceren Durmus Eda Celikbas Khaled Nabil Salama Suna Timur 《Electroanalysis》2021,33(4):1072-1080
eIF3d is a protein biomarker which has a potential for the diagnosis of various cancers. Herein, a bio-platform was constructed for eIF3d sensing by using LSG and surface functionalization with anti eIF3d antibody via EDC/NHS chemistry. Following the surface modifications, XPS and several electrochemical methods were used. Difference in the signals were related to biomarker amounts between 75–500 ng/mL. LOD was calculated as 50.4 ng/mL. Selectivity of biosensor was tested by using of various interference molecules. EIF3d was also successfully detected in synthetic biological samples. Thus, to the best of our knowledge, this study is one of the rare studies on use of LSGs in immunosensor studies. 相似文献
54.
Nicolas Brosse Alain Durmus Éric Moulines Sotirios Sabanis 《Stochastic Processes and their Applications》2019,129(10):3638-3663
In this article, we consider the problem of sampling from a probability measure having a density on proportional to . The Euler discretization of the Langevin stochastic differential equation (SDE) is known to be unstable, when the potential is superlinear. Based on previous works on the taming of superlinear drift coefficients for SDEs, we introduce the Tamed Unadjusted Langevin Algorithm (TULA) and obtain non-asymptotic bounds in -total variation norm and Wasserstein distance of order 2 between the iterates of TULA and , as well as weak error bounds. Numerical experiments are presented which support our findings. 相似文献
55.
56.
Z. Durmus M. Tomas A. Baykal H. Kavas T. Gürkaynak Altınçekiç M. S. Toprak 《Russian Journal of Inorganic Chemistry》2010,55(12):1947-1952
We report on the synthesis of Mn3O4 nanoparticles via a two-step hydrothermal route by using Mn(CH3COO)2 as the only starting material and TMAOH and NaOH as hydrolysing agents. XRD and FT-IR analyses confirmed the composition and structure of Mn3O4. TEM images showed that spheroid Mn3O4 nanostructures obtained by this method have average particle size of 6 and 14 nm for NaOH and TMAOH hydrolyzed samples respectively. Particle size analysis indicated a strong aggregation of nanoparticles and exhibited bi-modal distribution with average size of aggregates as ~250 nm and 1.1 μm for both samples. Zeta potential analysis revealed adsorbed TMAOH species on the surface of Mn3O4 nanoparticles hydrolyzed using TMAOH. ESR analyses resulted in broader lines and smaller g values than bulk Mn3O4 nanoparticles, probably due to the exchange-coupled system with unlike spins such as canted spin at surface of high-surface-disordered nanoparticles. 相似文献
57.
Poly(vinyl phosphonic acid) (PVPA)-Fe3O4 nanocomposite is synthesized by the precipitation of Fe3O4 in the presence of PVPA. Structural, surface, morphological, thermal properties and conductivity characterization/evaluation of the nanocomposite were performed by XRD, FT-IR, TEM, TGA and conductivity measurements respectively. The capping of PVPA around the Fe3O4 nanoparticles was confirmed by FT-IR spectroscopy, the interaction being via bridging oxygens of the phosphate and the nanoparticle surface. The crystallite and particle size were obtained as 6 ± 2 and 8.7 ± 0.1 nm from XRD line profile fitting and TEM image analysis respectively, which reveal nearly single crystalline nature of the Fe3O4 nanoparticles. Magnetic characterization of the bulk magnetite and (PVPA)-Fe3O4 nanocomposite reveals that both are in the superparamagnetic state at room temperature. The average magnetic domain size of the nanoparticles has been calculated using the Langevin function, which was fitted to the measured M-H hysteresis curves as 7.6 nm for the nanocomposite. In the nanocomposite, the reduction is due to the adsorption of PVPA onto the magnetite surface, which cancels some of the free spins at the surface causing a magnetically dead layer. Analysis of the conductivity and permittivity measurements revealed the coupling of ionic and polymer segmental motions and strong temperature dependency in the nanocomposite. 相似文献
58.
Fazilet Zumrut Biber Muftuler Perihan Unak Çigdem Içhedef Ilknur Demir 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):679-689
Tamoxifen [TAM; ([Z]-2-[4-(1,2-diphenyl-1-di-butenyl)-phenoxy]-N,N-dimethylethanamine) has been used as an antiestrogen drug for treatment and prevention of human breast cancer. The aim of
this study is conjugation of hydrophilic glucuronic acid to the starting substance TAM and labeling with 131I using iodogen as oxidizing agent. The reactions are completed in three steps, including enzymatic reaction, with the following
sub-steps; preparation of microsomal fraction from rat liver and subsequent purification of UDP-glucuronyl transferase (UDPGT),
estimation of protein amount in microsomal samples and glucuronidation reaction. Synthesized glucuronide derivative (TAM-G)
was purified using high performance liquid chromatography (HPLC). Mass spectroscopy of cold standard showed that the labeling
most probably occurs in ortho position to the aromatic ring containing the ether group of TAM-G as expected. Radiochemical
yield of the 131I labeled TAM-G ([131I]TAM-G) is determined by using Thin Layer Radio Chromatography (TLRC). The radiopharmaceutical potential of [131I]TAM-G is examined by biodistribution studies that is run on normal female Albino Wistar rats. According to biodistribution
results 131I labeled TAM-G may be proposed as a new antiestrogen glucuronide imaging agent for breast and uterus. 相似文献
59.
E. Ilker Medine Perihan Ünak Serhan Sakarya Feriha Özkaya 《Journal of nanoparticle research》2011,13(10):4703-4715
Modification of the magnetic properties of a drug can be used to direct the drug to the desired site, enhancing its therapeutic
effectiveness and reducing side effects. In this study, surface-modified magnetic nanoparticles were immobilized with uracil
glucuronide derivatives and then labeled with I-125. The morphology, structure, and composition of the magnetic particles
were examined by TEM, SEM, VSM, and XRD. The particles sizes were about 50 nm. The labeling yield was 93.8% for uracil-O-glucuronide-immobilized magnetic particles and 95.0% for uracil-N-glucuronide-immobilized magnetic particles. The cell incorporation rates of N- and O-glucuronides were higher than those of uracil. The incorporation rates of uracil-, O-glucuronide-, and N-glucuronide-conjugated magnetic particles were all high. The cell incorporation rates of ligand-conjugated magnetic particles
increased under a magnetic field. 相似文献
60.
Durmus Demir Oleg Lebedev Keith A. Olive Maxim Pospelov Adam Ritz 《Nuclear Physics B》2004,680(1-3):339-374
Within the minimal supersymmetric standard model (MSSM), the large tanβ regime can lead to important modifications in the pattern of CP-violating sources contributing to low energy electric dipole moments (EDMs). In particular, four-fermion CP-violating interactions induced by Higgs exchange should be accounted for alongside the constituent EDMs of quarks and electrons. To this end, we present a comprehensive analysis of three low energy EDM observables—namely the EDMs of thallium, mercury and the neutron—at large tanβ, in terms of one- and two-loop contributions to the constituent EDMs and four-fermion interactions. We concentrate on the constrained MSSM as well as the MSSM with nonuniversal Higgs masses, and include the CP-violating phases of μ and A. Our results indicate that the atomic EDMs receive significant corrections from four-fermion operators, especially when Im(A) is the only CP-violating source, whereas the neutron EDM remains relatively insensitive to these effects. As a consequence, in a large portion of the parameter space, one cannot infer a separate bound on the electron EDM via the experimental constraint on the thallium EDM. Furthermore, we find that the electron EDM can be greatly reduced due to the destructive interference of one- and two-loop contributions with the latter being dominated by virtual staus. 相似文献