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991.
A 50‐year‐old man with diabetes mellitus with diabetic retinopathy, peripheral neuropathy, hypertension, and end‐stage renal disease on maintenance hemodialysis, presented with persistent cough and hiccups, continued to be unwell with weight loss, poor appetite, and recurrent respiratory symptoms such as wheezing and cough. Whole body positron emission tomography‐computed tomography scan showed metabolically active lesions in liver, stomach/lesser sac, pancreas, and left sixth rib. As he had repeated bilateral transudative pleural effusion, left mini thoracotomy with pleural biopsy showed no evidence of granuloma or malignancy. Upper gastroscopy showed tiny gastric polyp; biopsy revealed benign lesion. Left posterior rib biopsy from the lesion and iliac crest biopsy showed no evidence of malignancy or granuloma. Further evaluation showed plasma chromogranin A ?5737 μg/L (<100 μg/L) with a repeat value of 6950 μg/L (<100 μg/L). He was initiated on oral sunitinib 25 mg once a day and injection octreotide 20 mg subcutaneously once a month. The plasma chromogranin A level and his symptoms, however, showed an initial improvement, but gradually worsened after 4 months despite being on treatment. After 6 months, the patient developed a gangrenous lesion of his glans penis with necrosis. Due to severe pain on conservative measures, penectomy with perineal urethrostomy was performed. Biopsy of the lesion showed blood vessels with intimal calcifications and thrombosis suggesting penile necrosis.  相似文献   
992.
Bent-core liquid crystals (LCs) introduced a whole new dimension to the science of LCs. Besides re-emphasizing the importance of the shape of the molecule, they brought in phases with symmetry, not known earlier. Another sub-class of systems that is emerging is that of soft-bent molecules. In contrast with the bent-core molecules, here the bend is achieved through the parity of the aliphatic linker that connects two monomers. They hold the unique advantage that a simple variation of temperature can favour different conformer states and thus govern the self-assembled structure. A highlight of the power of this route is seen in terms of the discovery of a new type of nematic, viz., twist–bend nematic. Investigations on not only this phase but also the regular nematic that often precedes it have received significant attention in the last few years. Here we present results on the regular nematic phase of a binary mixture comprising such a soft-bent dimer, known in the literature as CB7CB, by incorporating zinc oxide nanorods (NRs) into the system. The NRs with an aspect ratio of \({\sim }\)7.2, not very different from that of LCs, further accentuate the importance of shape and shape anisotropy of the entities. Specifically, we observe that the nematic–isotropic transition temperature increases by \({\sim }\)1.9 K even for a low concentration of 4% NRs. While the dielectric anisotropy decreases, birefringence shows a substantial increase, adding to the complexity of the influence. Upon addition of minute amount of NRs (1%), while the splay elastic constant gets enhanced, its bend counterpart not only gets reduced but retains the convex-shaped thermal profile seen for the parent mixture.  相似文献   
993.
Maintainers can use information from test analysis tools to help them understand, debug, and retest programs. The authors describe techniques and tools in Bellcore's χSuds, a system for understanding and diagnosing software bugs, including Y2K problems in legacy applications  相似文献   
994.
A major field of neural networks (NN) application is function estimation, because the useful properties of NN such as adaptivity and nonlinearity are well suited to function estimation tasks where the equation describing the function is unknown. In this paper the prerequisite training data are obtained from experimental studies performed on a flat plate model for a polluted insulator under power frequency voltage. Detailed studies have been carried to determine the NN parameters which give the best results. Studies have also been carried out to assess the effect of the presence of inadequate data in the training set on modeling accuracy. It is found that, when training is completed, NN is capable of estimating the function t=f(V,L,Rp ) very efficiently and effectively even when the inadequate data are incorporated in the training set  相似文献   
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Differential evolution (DE) is one of the most powerful stochastic real parameter optimizers of current interest. In this paper, we propose a new mutation strategy, a fitness-induced parent selection scheme for the binomial crossover of DE, and a simple but effective scheme of adapting two of its most important control parameters with an objective of achieving improved performance. The new mutation operator, which we call DE/current-to-gr_best/1, is a variant of the classical DE/current-to-best/1 scheme. It uses the best of a group (whose size is q% of the population size) of randomly selected solutions from current generation to perturb the parent (target) vector, unlike DE/current-to-best/1 that always picks the best vector of the entire population to perturb the target vector. In our modified framework of recombination, a biased parent selection scheme has been incorporated by letting each mutant undergo the usual binomial crossover with one of the p top-ranked individuals from the current population and not with the target vector with the same index as used in all variants of DE. A DE variant obtained by integrating the proposed mutation, crossover, and parameter adaptation strategies with the classical DE framework (developed in 1995) is compared with two classical and four state-of-the-art adaptive DE variants over 25 standard numerical benchmarks taken from the IEEE Congress on Evolutionary Computation 2005 competition and special session on real parameter optimization. Our comparative study indicates that the proposed schemes improve the performance of DE by a large magnitude such that it becomes capable of enjoying statistical superiority over the state-of-the-art DE variants for a wide variety of test problems. Finally, we experimentally demonstrate that, if one or more of our proposed strategies are integrated with existing powerful DE variants such as jDE and JADE, their performances can also be enhanced.  相似文献   
999.
The synthesis of bismuth ferrite by solid-state reaction of Bi2O3 and Fe2O3 results in the formation of multiphase products. Even coprecipitation followed by calcination leads to the formation of impurity phases. Here, we report the synthesis of magnetoelectric bismuth ferrite by a ferrioxalate precursor method. In this process, bismuth ferrite, synthesized through solutions of some specific salts led to the formation of phase pure (perovskite) nanocrystalline powder (11–22 nm as evident from X-ray diffraction analysis) at a temperature of 600 °C. The synthesized powders were characterized by X-ray diffractometry, thermogravimetry and differential thermal analysis, Fourier transformation infrared spectroscopy and scanning electron microscopy. The synthesis route is simple, energy saving and cost-effective. Such nanosized bismuth ferrite powder may have a potential application in making lead free piezoelectric materials for actuators as well as magnetoelectric sensors.  相似文献   
1000.
A UML-based pattern specification technique   总被引:2,自引:0,他引:2  
Informally described design patterns are useful for communicating proven solutions for recurring design problems to developers, but they cannot be used as compliance points against which solutions that claim to conform to the patterns are checked. Pattern specification languages that utilize mathematical notation provide the needed formality, but often at the expense of usability. We present a rigorous and practical technique for specifying pattern solutions expressed in the unified modeling language (UML). The specification technique paves the way for the development of tools that support rigorous application of design patterns to UML design models. The technique has been used to create specifications of solutions for several popular design patterns. We illustrate the use of the technique by specifying observer and visitor pattern solutions.  相似文献   
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