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151.
Primary intramedullary anaplastic oligodendroglioma is a rare tumor, only four cases of which have been reported. The authors present the case of a 38-month-old boy with primary intramedullary anaplastic oligodendroglioma. He underwent partial removal of the tumor and spinal radiation therapy. The residual tumor disappeared 12 months after radiation, and 48 months after treatment there was no evidence of recurrence. This case shows that in primary intramedullary anaplastic oligodendroglioma, postoperative radiation therapy confined to the spinal cord can yield an optimal result.  相似文献   
152.
Machine learning approaches for medical decision-making processes are valuable when both high classification accuracy and less feature requirements are satisfied. Artificial neural networks (ANNs) successfully meet the first goal with its adaptive engine, while nature-inspired algorithms are focusing on the feature selection (FS) process in order to eliminate less informative and less discriminant features. Besides engineering applications of ANN and FS algorithms, medical informatics is another emerging field using similar methods for medical data processing. Classification of psychiatric disorders is one of the major focus of medical informatics using artificial intelligence approaches. Being one of the most debilitating psychiatric diseases, bipolar disorder (BD) is frequently misdiagnosed as unipolar disorder (UD), leading to suboptimal treatment and poor outcomes. Thus, discriminating UD and BD at earlier stages of illness could therefore help to facilitate efficient and specific treatment. The use of quantitative electroencephalography (EEG) cordance as a biomarker has greatly enhanced the clinical utility of EEG in psychiatric and neurological subjects. In this context, the paper puts forward a study using two-step hybridized methodology: particle swarm optimization (PSO) algorithm for FS process and ANN for training process. The noteworthy performance of ANN–PSO approach stated that it is possible to discriminate 31 bipolar and 58 unipolar subjects using selected features from alpha and theta frequency bands with 89.89 % overall classification accuracy.  相似文献   
153.
Fast contact handling of soft articulated characters is a computationally challenging problem, in part due to complex interplay between skeletal and surface deformation. We present a fast, novel algorithm based on a layered representation for articulated bodies that enables physically-plausible simulation of animated characters with a high-resolution deformable skin in real time. Our algorithm gracefully captures the dynamic skeleton-skin interplay through a novel formulation of elastic deformation in the pose space of the skinned surface. The algorithm also overcomes the computational challenges by robustly decoupling skeleton and skin computations using careful approximations of Schur complements, and efficiently performing collision queries by exploiting the layered representation. With this approach, we can simultaneously handle large contact areas, produce rich surface deformations, and capture the collision response of a character/s skeleton.  相似文献   
154.
Nalan zbay  Nuray Oktar  N. Alper Tapan 《Fuel》2008,87(10-11):1789-1798
Although WCO plays a crucial role for the economical production of biodiesel, free fatty acid (FFA) level in the nature of WCO cause saponification problems during transesterification. Acidic ion-exchange resins can be used to decrease WCO free fatty acid level. In this study, activities of resins (Amberlyst-15 (A-15), Amberlyst-35 (A-35), Amberlyst-16 (A-16) and Dowex HCR-W2) in direct FFA esterification were examined in the temperature range of 50–60 °C and the effect of catalyst amount (1–2 wt%) on FFA conversion was also analyzed. FFA conversion increased with increasing reaction temperature and catalyst amount. Order of catalytic activities was found as A-15 > A-35 > A-16 > Dowex HCR-W2. This was related to the size of average pore diameters and magnitude of BET surface area.  相似文献   
155.
156.
In this work, design and measurement results of UHF RF frontend circuits to be used in low-IF and subsampling receiver architectures are presented. We report on three low noise amplifiers (LNA) (i) single-ended (ii) differential (iii) high-gain differential and a double-balanced mixer all implemented in 0.35-μ m SOI (Silicon on Insulator) CMOS technology of Honeywell. These circuits are considered as candidate low-power building blocks to be used in the two fully-integrated receiver chips targeted for deep space communications. Characteristics of square spiral inductors with high quality (Q) factors (as high as 10.8) in SOI CMOS are reported. Single-ended and fully-differential LNA's provide gains of 17.5 dB and 18.74 dB at 435 MHz, respectively. Noise figure of the single-ended LNA is 2.91 dB while the differential LNA's noise figure is 3.25 dB. These results were obtained for the power dissipations of 12.5 mW and 16.5 mW from a 2.5-V supply for the single-ended and differential LNA's, respectively. High-gain low-power differential LNA provides a small-signal gain of 45.6 dB with a noise figure of 2.4 dB at 435 MHz. Total power dissipation of the high gain LNA is 28 mW from a 3.3-V supply. The double-balanced mixer provides a conversion gain of 5.5 dB with a noise figure of 13 dB at 2 MHz IF. The power dissipation of the mixer is 11.5 mW from a 2.5-V supply. The measured responses and the power dissipations of the building blocks meet the requirements of the communications system. The die areas occupied by the single-ended LNA, differential LNA, high-gain LNA and the mixer are 0.6 mm × 1.4 mm, 1 mm × 1.4 mm, 1.4 mm × 1.2 mm and 0.6 mm × 0.9 mm, respectively. Ertan Zencir received the B.Sc. and M.S. degrees in electrical and electronics engineering from Middle East Technical University, Ankara, Turkey, and Ph.D. degree in electrical engineering from Syracuse University, Syracuse, NY in 1995, 1997, and 2003, respectively. He joined the Electrical Engineering and Computer Science Department of University of Wisconsin-Milwaukee as an Assistant Professor in August 2004. 2003). His current research focuses on RFIC and transceiver design for wireless communications. Douglas Te-Hsin Huang was born in Chia-yi Taiwan. He received the B.S. degree in electrical engineering from National Taiwan Ocean University, Kee-lung, Taiwan in 1993, and the M.S. and Ph.D. degrees in electrical engineering from Syracuse University, Syracuse, New York, in 2001 and 2003, respectively. In 2004, he joined Skyworks Solutions Inc., where he is currently an RFIC Design Engineer. His research deals mainly with low-power, infrastructure, analog RFIC, and microwave integrated circuit designs. Besides microwave and semiconductor engineering, Dr. Huang has broad interest in art, music, and philosophy. Ahmet Tekin received his B.S. degree in Electrical Engineering from Bogazici University, Istanbul, Turkey in 2002 and MS degree in Electrical engineering form North Carolina A&T State University, Greensboro, NC. He is currently working towards his PhD degree at University of California, Santa Cruz, CA. He was a Research Assistant at RF Microelectronic Laboratory, North Carolina A&T State University, from 2002 to 2004. He worked on the design of low power UHF transceiver circuits for space applications. He is currently a Research Assistant at Bio-mimetic Microelectronic Systems Laboratory, University of California at Santa Cruz, working on implantable very low power UHF frequency transceiver for a body sensor network. Numan S. Dogan received the B.Sc. degree from Karadeniz Technical University, Trabzon, Turkey, in 1975, the M.Sc. degree from Polytechnic University, New York, in 1979, and the PhD degree from the University of Michigan, Ann Arbor, in 1986, all in electrical engineering. Since 1998, he has been with the Electrical and Computer Engineering Department, North Carolina A&T State University, Greensboro, North Carolina, where he is an Associate Professor. He was a Visiting Faculty Researcher at Air Force Research Laboratory (AFRL), Eglin Air Force Base, Florida, in 1998, and General Electric Corporate Research and Development Laboratory, Schenectady, New York, in 1999. His earlier research interests included microwave and millimeter-wave solid-state devices and circuits, high-temperature electronics, and silicon micromachining. His recent research interests include RF CMOS Integrated Circuits and low-power Medical Implant Communication Systems (MICS) transceivers. Currently he serves as the Chair of the IEEE Central North Carolina Section. In April 2004, he organized “a walking robot competition” for High School Students. He enjoys hiking to Alpine Lakes in the Pacific Northwest and fishing. Ercument Arvas (M'85–SM'89) received the B.S. and M.S. degrees from METU, Ankara, Turkey, in 1976 and 1979, respectively, and the Ph.D. degree from Syracuse University, Syracuse, New York, in 1983, all in Electrical Engineering. Between 1984 and fall of 1987, he was with the Electrical Engineering Department of Rochester Institute of Technology, Rochester, New York. He joined the Electrical Engineering and Computer Science Department of Syracuse University in 1987, where he is currently a Professor. His research interests include numerical electromagnetics, antennas, and microwave circuits and devices.  相似文献   
157.
    
Resistant starch (RS) passes through the small intestine undigested and is fermented in the large intestine. Due to this feature, RS functions as a prebiotic and, RS is added to various foods as a functional fiber. RS for traditional fiber has various advantages, such as increased viscosity, gel form, and volume increase. In terms of these advantages, RS, which is commercially produced, is used in the food industry for bread, breakfast cereals, cooked products, and pasta products. Bread is a food that is frequently consumed in human nutrition. Although bread is a frequent food, the fiber content of the bread is low and the glycemic index (GI) of the bread is high. For this reason, bread-RS is used to convert the bread into a healthier version. Adding RS to bread increases the bread's fiber content and decreases the GI of the bread. RS reduces not only the GI of foods but also the glycemic response of individuals after consumption. RS, which can be fermented in the colon, is converted into short-chain fatty acids (SCFAs) because of fermentation. RS affects glucose and insulin levels through the production of SCFA, which increases glucose uptake in the muscles and liver, releases intestinal hormones, and increases insulin sensitivity. The addition of RS to bread results in a product with a high fiber content and a low GI.  相似文献   
158.
This paper presents a meta-synthesis conducted to identify, compare and synthesize published qualitative data related to the Maggie's Centres, as a paradigmatic architectural example in the provision of non-institutional cancer support. These centres are internationally renowned for their unique architecture, where the careful design of indoors and outdoors spaces plays a critical role in their agenda for supporting care. Previous research has thoroughly analysed this approach to therapeutic environments, not only confirming the importance of designed space as originally conceived in Maggie's philosophy but also identifying precise supporting effects associated with specific elements within their design. This paper aims to provide a new reading of Maggie's contribution to cancer support by offering an examination of all these data through the lens of biophilia, which clarifies the impact of design decisions connected to nature on cancer patients' lives. The analytic process included a systematic search strategy, extraction and classification of salient concepts using an open-coding approach, and lastly an interpretive evaluation. The systematically selected data helped to identify and rank the biophilic design parameters that appear the most critical for promoting and supporting human health and wellbeing in non-clinical therapeutic environments, from the user's perspective. It also provided a compilation of distinctive design interventions related to biophilic parameters, which provides benchmark information for future research and design guidance in these environments.  相似文献   
159.
160.
In this paper, a new technique for realizing area-efficient, low-noise filters is introduced. The proposed filter topologies utilize noise shaping techniques to shift the noise of the passive and active filter components out of the passband of the filter. This is illustrated by implementing a programmable noise-shaped post-mixer gain-filtering circuit for a CMOS Mobile-TV tuner. The proposed circuits relax the noise-linearity tradeoff in the receiver chain by providing blocker rejection following the mixer outputs. The filter provides an in-band input referred noise density as low as 7.5 nV/sqrt(Hz). The measured out-of-band IIP3 values are 30 dBV and 31.5 dBV for the 3.8-MHz (DVB-H) and 750-kHz (ISDB-T) modes, respectively. Total current consumption is 5.5 mA from a 1.2-V supply. The gain of the block is programmable to be 0 dB, 8 dB, 14 dB, or 20 dB. The design occupies a die area of 0.28 mm2 in a 65-nm CMOS process covering a frequency band of 700 kHz to 5.2 MHz as a universal mobile-TV integrated baseband gain-filtering solution.  相似文献   
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