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951.
Hye Jeong Lee Jeffrey J. Luci Mohammed N. Tantawy Haakil Lee Ki Taek Nam Todd E. Peterson Ronald R. Price 《Magnetic resonance imaging》2013
Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) is a relatively new diffusion-based pulse sequence that produces positron emission tomography (PET) with 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (18F-FDG)-like images. We tested the feasibility of DWIBS in detecting peritoneal ovarian cancer in a syngeneic mouse model. Female C57BL/6 mice were injected intraperitoneally with ID8 murine ovarian carcinoma cells. After 11 weeks, the abdomen was imaged by DWIBS. A respiratory gating diffusion-weighted spin-echo echo-planar imaging in abdomen was used (imaging parameters of field of view of 47×47 mm2, matrix size of 64×64 zero-filled to 256×256 and b-value of 1500 s/mm2). We also performed FDG microPET as the reference standard. For comparison of the correlating surface areas of tumor foci on both DWIBS and FDG microPET imaging, two-dimensional region-of-interest (ROI) analysis was performed, and correlation between the two modalities was determined. Mice were also subjected to macroscopic examination for tumor location and pathology after imaging. DWIBS in all mice depicted the tumors as abnormal high signal intensity. The results show that the ROI analysis of correlating lesions reveals relatively high correlation (r²=0.7296) and significant difference (P = .021) between DWIBS and FDG microPET. These results demonstrate that DWIBS has the potential for detecting peritoneal dissemination of ovarian cancer. Nonetheless, due to low ratios of image signal-to-noise and motion artifacts, DWIBS can be limited for lesions near the liver. 相似文献
952.
Muhammad Usman Ghani Muhammad Sagir Muhammad Bilal Tahir Sami Ullah Mohammed Ali Assiri 《International journal of quantum chemistry》2024,124(3):e27340
Halide base perovskite LiCdX3 (X = F, Cl) is tested by CASTEP (Cambridge Serial Total Energy Package) based on density function theory (DFT). The presented discussion is to explore the structural, electronic, and optical properties of LiCdX3 (X = F, Cl). The calculated values of the lattice parameter are found to be 3.8 Å and 5.27 Å of LiCdF3 and LiCdCl3 respectively. The ideal structure of LiCdX3 (X = F, Cl) is cubic and dynamically stable. Electronic properties show that materials are semiconductors. The results from band structure are further evaluated by the total and partial density of states. The partial and total density of states confirms the degree of localization of electrons. In optical properties, the highest absorption coefficient is observed in LiCdCl3. The material is half metallic and has a narrow indirect band gap which may be used in photovoltaic applications. 相似文献
953.
In this article, we introduce and study the rings over which every module is (strongly) Gorenstein flat, which we call them (strongly) Gorenstein Von Neumann regular rings. 相似文献
954.
In this note, we show that some $F$ -harmonic maps into spheres are global maxima of the variations of their energy functional on the conformal group of the sphere. Our result extends partially those obtained in El Soufi and Lejune [C.R.A.S. 315(Serie I):1189–1192, 1992] and El Soufi [Compositio Math 95:343–362,1995] for harmonic and $p$ -harmonic maps. 相似文献
955.
In this paper, we apply the disconjugacy theory and Elias's spectrum theory to study the positivity and the spectrum structure of the linear operator coupled with the clamped beam boundary conditions (1.2). We also study the positivity and the spectrum structure of the more general operator coupled with (1.2). As the applications of our results on positivity and spectrum of fourth‐order linear differential operators, we show the existence of nodal solutions for the corresponding nonlinear problems via Rabinowitz's global bifurcation theorem. 相似文献
956.
Mokhtar Kirane Salman A. Malik Mohammed A. Al‐Gwaiz 《Mathematical Methods in the Applied Sciences》2013,36(9):1056-1069
We consider the inverse source problem for a time fractional diffusion equation. The unknown source term is independent of the time variable, and the problem is considered in two dimensions. A biorthogonal system of functions consisting of two Riesz bases of the space L2[(0,1) × (0,1)], obtained from eigenfunctions and associated functions of the spectral problem and its adjoint problem, is used to represent the solution of the inverse problem. Using the properties of the biorthogonal system of functions, we show the existence and uniqueness of the solution of the inverse problem and its continuous dependence on the data. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
957.
Mohammed Berkhouch Ghizlane Lakhnati Marcelo Brutti Righi 《Applied Mathematical Finance》2013,20(3):295-314
ABSTRACTThe aim of this paper is to introduce a risk measure, Extended Gini Shortfall (EGS), that extends the Gini-type measures of risk and variability by taking risk aversion into consideration. Our risk measure is coherent and catches variability, an important concept for risk management. The analysis is made under the Choquet integral representations framework. We expose results for analytic computation under well-known distribution functions. Furthermore, we provide a practical application. 相似文献
958.
We introduce and study the class of almost weak Dunford–Pettis operators and we derive the following interesting consequence: other characterizations of the weak Dunford–Pettis property. After that we characterize pairs of Banach lattices for which the adjoint of almost weak Dunford–Pettis operator is almost Dunford–Pettis. Finally, we establish a necessary and sufficient conditions on the pair of Banach lattices E and F which guarantees that if T : E → F is a positive almost weak Dunford–Pettis then T is almost Dunford–Pettis. 相似文献
959.
Dumbre S Derouaux A Lescrinier E Piette A Joris B Terrak M Herdewijn P 《Journal of the American Chemical Society》2012,134(22):9343-9351
The peptidoglycan glycosyltransferases (GTs) are essential enzymes that catalyze the polymerization of glycan chains of the bacterial cell wall from lipid II and thus constitute a validated antibacterial target. Their enzymatic cavity is composed of a donor site for the growing glycan chain (where the inhibitor moenomycin binds) and an acceptor site for lipid II substrate. In order to find lead inhibitors able to fill this large active site, we have synthesized a series of substrate analogues of lipid I and lipid II with variations in the lipid, the pyrophosphate, and the peptide moieties and evaluated their biological effect on the GT activity of E. coli PBP1b and their antibacterial potential. We found several compounds able to inhibit the GT activity in vitro and cause growth defect in Bacillus subtilis . The more active was C16-phosphoglycerate-MurNAc-(L-Ala-D-Glu)-GlcNAc, which also showed antibacterial activity. These molecules are promising leads for the design of new antibacterial GT inhibitors. 相似文献
960.
Khalil EL KHATABI Ilham AANOUZ Reda El-MERNISSI Atul Kumar SINGH Mohammed Aziz AJANA Tahar LAKHLIFI Shashank KUMAR Mohammed BOUACHRINE 《Turkish Journal of Chemistry》2021,45(3):647
Alzheimer’s disease (AD) is a multifactorial and polygenic disease. It is the most prevalent reason for dementia in the aging population. A dataset of twenty-six 1,2,3-triazole-based derivatives previously synthetized and evaluated for acetylcholinesterase inhibitory activity were subjected to the three-dimensional quantitative structure-activity relationship (3D-QSAR) study. Good predictability was achieved for comparative molecular field analysis (CoMFA) (Q2 = 0.604, R2 = 0.863, rext2 = 0.701) and comparative molecular similarity indices analysis (CoMSIA) (Q2 = 0.606, R2 = 0.854, rext2 = 0.647). The molecular features characteristics provided by the 3D-QSAR contour plots were quite useful for designing and improving the activity of acetylcholinesterase of this class. Based on these findings, a new series of 1,2,3-triazole based derivatives were designed, among which compound A1 with the highest predictive activity was subjected to detailed molecular docking and compared to the most active compound. The selected compounds were further subjected to 20 ns molecular dynamics (MD) simulations to study the comparative conformation dynamics of the protein after ligand binding, revealing promising results for the designed molecule. Therefore, this study could provide worthy guidance for further experimental analysis of highly effective acetylcholinesterase inhibitors. 相似文献