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61.
In this study, different melt treatment operations were evaluated and compared to end product’s scrap rate using bifilm index (BI) method. Results clearly show that degassing with finer gas bubbles increases cleaning performance for the removal of any type of bifilms in the melt. BI method is a reliable and quick way to determine melt quality at any given time during casting process which is found to have a direct correlation with rejection rate.  相似文献   
62.
PURPOSE: Following intravesical bacillus Calmette-Guerin (BCG) instillation, we attempted to detect BCG in the blood using the polymerase chain reaction (PCR) method and correlate these findings with the occurrence of major complications due to this treatment. MATERIALS AND METHODS: Intravesical BCG immunotherapy was given to 22 consecutive patients with superficial bladder tumors. In 2 patients the BCG instillation had to be discontinued due to serious side effects of therapy. Blood samples (252 aliquots) were obtained from 126 BCG courses in 22 cases, and 2 additional samples (4 aliquots) were obtained from 1 patient 1 and 3 months after cessation of therapy. All blood samples were analyzed by the PCR technique for detection of deoxyribonucleic acid tuberculosis Mycobacterium tuberculosis. RESULTS: Of the 126 blood samples 9 (7.1%) were PCR positive for M. tuberculosis. These 9 positive samples belonged to 3 patients, all of whom were among those 4 patients who had major clinical side effects. CONCLUSIONS: We demonstrated that rapid and sensitive detection of mycobacteremia by PCR correlated with the clinical course of these patients. We also demonstrated that PCR can be used to monitor BCG in the blood after antituberculous therapy. The early, fast and accurate diagnosis of BCG in the blood by PCR may alter the serious clinical course of these patients by initiation of specific treatment early. However, further extensive studies are needed to validate these results.  相似文献   
63.
Design considerations are presented for attaining accurate output balancing in fully differential operational amplifiers over the useful operating frequency of the differential signals. Such output balancing is obtained by merging the common-mode feedback and the differential gain paths as close to the front end of the amplifier as possible, ensuring maximum sharing of circuit components. Two circuit designs implemented in a 5-V, 1.75-μm process are presented, one based on a two-stage topology and one based on a folded cascode topology. Experimental results for both designs are given  相似文献   
64.
The development of a low-power 12-channel multiplexer-demultiplexer pair that is clocked at the standard synchronous optical network (SONET) rate of 622.08 MHz is discussed. Each device has been integrated in silicon using a 0.75- mu m NMOS VLSI technology that provides high fabrication yield at relatively low cost. Highlighted are the analog interface circuits of the two chips. These include a phase splitter and amplifier for the maser clock input, a precision 50- Omega output driver for high-speed synchronous-transport-signal-12 (STS-12) data, as well as input amplifier and an output stage for low-speed differential STS-1 data.<>  相似文献   
65.
In this study, a series of theophylline‐loaded calcium pectin gel films were prepared in three different Ca+2 concentrations with three different methods for wound dressing applications. Drug release performance of the films were investigated in four different medium pH in order to mimic wound healing pH conditions. Hydrogel films were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy and atomic force microscopy. Their absorbency (fluid handling), swelling behavior, dehydration rate, dispersion characteristic, dressing pH determination, water vapor permeability, oxygen permeability, surface contact angle, flexibility, Shore A hardness, mean mass per unit area and thickness were determined. The effect of the hydrogels on wound healing was evaluated with an in vitro wound healing assay. After evaluating all data, we suggested that the hydrogel film prepared with swelling method using 7% or 10% crosslinker and dried at 26 °C is more suitable for controlled drug release process. We showed that between pH 3.25 and 7.12 the form of the hydrogel did not change, and drug release was continuous. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46731.  相似文献   
66.

Tele-health and e-healthcare are some of the innovative e-commerce appliances that can eliminate the barrier between time and distance among health care centres and patients. The proposed work approaches the obstacle to secure digital medical image data in a public cloud. The most crucial part of e-healthcare and telemedicine industries is cyber-attacks. To thwart cyber-attacks, it is necessary to protect the medical images and transmit them securely. In this paper, a novel way of scrambling and Deoxyribonucleic Acid (DNA) sequence operations is performed to encrypt the digital medical images. A chaotic tri-level scrambling is carried out by a two dimensional Tinkerbell map. Experimental outcomes and security analyses such as statistical, differential, keyspace, encryption quality, along with chosen-plaintext attack analysis have been perpetrated to determine the feasibility and potency of the proposed Digital Imaging and Communications in Medicine (DICOM) image encryption method. The algorithm attains average entropy of 7.99 and near-zero correlation with NPCR and UACI of 99.6 and 33.4, respectively. Further, the efficiency of the algorithm is compared with the state of the literature encryption techniques.

  相似文献   
67.
Fetal heart rate helps in diagnosing the well-being and also the distress of fetal. Cardiotocograph (CTG) monitors the fetal heart activity to estimate the fetal tachogram based on the evaluation of ultrasound pulses reflected from the fetal heart. It consists in a simultaneous recording and analysis of fetal heart rate signal, uterine contraction activity and fetal movements. Generally CTG comprises more number of features. Feature selection also called as attribute selection is a process of selecting a subset of highly relevant features which is responsible for future analysis. In general, medical datasets require more number of features to predict an activity. This paper aims at identifying the relevant and ignores the redundant features, consequently reducing the number of features to assess the fetal heart rate. The features are selected by using unsupervised particle swarm optimization (PSO)-based relative reduct (US-PSO-RR) and compared with unsupervised relative reduct and principal component analysis. The proposed method is then tested by applying various classification algorithms such as single decision tree, multilayer perceptron neural network, probabilistic neural network and random forest for maximum number of classes and clustering accuracies like root mean square error, mean absolute error, Davies–Bouldin index and Xie–Beni index for minimum number of classes. Empirical results show that the US-PSO-RR feature selection technique outperforms the existing methods by producing sensitivity of 72.72 %, specificity of 97.66 %, F-measure of 74.19 % which is remarkable, and clustering results demonstrate error rate produced by US-PSO-RR is less as well.  相似文献   
68.
As the use of unmanned aerial vehicles expands to near earth applications and force multiplying scenarios, current methods of operating UAVs and evaluating pilot performance need to expand as well. Many human factors studies on UAV operations rely on self reporting surveys to assess the situational awareness and cognitive workload of an operator during a particular task, which can make objective evaluations difficult. Functional Near-Infrared Spectroscopy (fNIR) is an emerging optical brain imaging technology that monitors brain activity in response to sensory, motor, or cognitive activation. fNIR systems developed during the last decade allow for a rapid, non-invasive method of measuring the brain activity of a subject while conducting tasks in realistic environments. This paper investigates deployment of fNIR for monitoring UAV operator’s cognitive workload and situational awareness during simulated missions. The experimental setup and procedures are presented with some early results supporting the use of fNIR for enhancing UAV operator training, evaluation and interface development.  相似文献   
69.
International Journal of Steel Structures - Having knowledge of dynamic properties named as natural frequency and mode shapes during the design process is important to determine proper design...  相似文献   
70.
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