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41.
Magnetic resonance imaging (MRI) is the imaging tool of choice in the evaluation of prostate cancer. The main applications
of MR imaging in the management of prostate cancer are: (1) to guide targeted biopsy when prostate cancer is clinically suspected
and previous ultrasound-guided biopsy results are negative; (2) to localize and stage prostate cancer and provide a roadmap
for treatment planning; and (3) to detect residual or locally recurrent cancer after treatment. Other MR techniques such as
proton MR spectroscopic imaging (MRSI), diffusion-weighted imaging (DWI), and contrast-enhanced MRI (CE-MRI) complement conventional
MR imaging by providing metabolic and functional information that can improve the accuracy of prostate cancer detection and
characterization. In everyday clinical practice, and to account for patient comfort, MR imaging studies are limited to 1 h.
To obtain consistently high-quality images, a well-designed protocol is necessary. Routine MR imaging can be supplemented
by other MR techniques such as MRSI, DWI or CE-MRI depending on the expertise available and the clinical questions that need
to be answered. This review summarizes the role of MR imaging in the management of prostate cancer and describes practical
approaches to implementing anatomic, metabolic and functional MR imaging techniques in the clinic. 相似文献
42.
Electromagnetic interference shielding of magneto-dielectric (BaTiO3-Fe3O4) and magneto-conducting (f-MWCNT-Fe3O4) fillers based polymer electrolyte composites in the X-band have been studied in the present work. Magneto-dielectric and magneto-conducting fillers have been obtained by in situ preparation of Fe3O4 nanoparticles by chemical precipitation in the presence of BaTiO3 and functionalized multiwalled carbon nanotubes (f-MWCNT). Functionalization of MWCNT has resulted in their strong bonding with the polymer electrolyte adversely affecting the charge transport properties and shielding effectiveness. Dielectric, magnetic and conducting properties of the magneto-dielectric and magneto-conducting fillers are found to be significantly different as a result of coating by Fe3O4 nanoparticles on BaTiO3 and f-MWCNT. Combining two fillers in a single nanocomposite has exhibited non-complimentary addition of their individual properties. The ultra-sonication method of dispersion of the magneto-conducting filler has been found to give better conducting and shielding effectiveness in comparison to the homogenization method due to better disentanglement of the nanotubes. 相似文献
43.
Multimedia Tools and Applications - Speech recognition is one of the major research regions these days under speech processing. This paper depends on developing a whole process that takes the input... 相似文献
44.
45.
Social and spatial order in villages in India 总被引:1,自引:0,他引:1
Amita Sinha 《Landscape Research》1990,15(3):12-19
The paper explores the social, ecological, and religious factors which shape the village forms in India. Linear, nucleated and dispersed villages have been identified with different regions. Caste and kinship groups form the basic unit of a neighbourhood. The castes ranked on a hierarchical scale, locate themselves in a centre-periphery distribution in the village. This layout also expresses the duality between ritually pure and polluting space and defines the social interaction patterns between the different castes. 相似文献
46.
V K Jain Amita Gupta C R Jalwania Adarsh Kumar G K Singhal O P Arora D S Ahuja P P Puri R Singh M Pal 《Bulletin of Materials Science》1994,17(5):551-561
Efforts have been made to see the effect of some standard microelectronic processing steps on porous silicon. Our diffusion
experiments for making p-n junctions confirm that this material can withstand high temperatures of the order of 800°C to 1000°C.
A new technique for photolithography has been suggested to obtain porous silicon in selected areas. Etch stop method to control
the thickness of the porous layer and an organic protective layer for porous silicon have also been suggested. Models proposed
by other workers to explain luminescence in porous silicon are not sufficient to explain many experimental observations. A
hybrid model is suggested. 相似文献
47.
The less efficient markets offer scope for enhanced indexing (EI), an investment strategy of portfolio selection which seeks to earn more return than the benchmark index. In this context, we examine the use of relaxed second order stochastic dominance (RSSD) by introducing underachievement and overachievement variables in the second order stochastic dominance (SSD), for EI. We propose a linear optimization model that maximizes the mean return subject to the constraints formed using RSSD. We impose bounds on the ratio of the total underachievement to the sum of total underachievement and total overachievement variables depicting the risk-return tradeoff in the model. The proposed model for EI is inspired from many applications of SSD and almost SSD (ASSD). We examine the performance of the proposed model with the SSD model, EI model of maximizing mean return and minimizing the underperformance (MM) from the benchmark index, \(\epsilon \)-almost second order stochastic dominance (\(\epsilon \)-ASSD) model, and the naïve 1/N portfolio, on two Indian stock indices, CNX 100 and CNX 200, through a rolling window strategy. To widen the empirical analysis, we also compare all models on the eight publicly available real financial data sets from Beasley OR library through a single window strategy. The portfolios from the proposed model are shown to produce statistically significant mean excess return and excess Sharpe ratio (both from the benchmark indices) more often than the MM and \(\epsilon \)-ASSD models. Also, the portfolios from the proposed model always have smaller violation area in SSD constraints from benchmark indices than the MM and \(\epsilon \)-ASSD models. 相似文献
48.
Enhancing Efficiency of Perovskite Solar Cells via N‐doped Graphene: Crystal Modification and Surface Passivation 下载免费PDF全文
49.
Wireless Personal Communications - Answer sheet evaluation is a time-consuming task that requires lot of efforts by the teachers and hence there is a strong need of automation for the same. This... 相似文献
50.
A high-pressure stopped-flow apparatus was constructed which could be operative at hydrostatic pressures up to 3 kbar. Some preparative results on anionic sigma-complex formation reactions are presented up to 1.5 kbar between 2,4,6-trinitrobenzene (I) and hydroxide ion and between compound (I) and sulfite ion in water. It was found that this apparatus was sufficient to follow a chemical reaction whose half-life was longer than several milliseconds. 相似文献