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991.
Shaikh Rahamatullah Shirazian Saeed Walker Gavin M. 《Neural computing & applications》2021,33(19):12621-12640
Neural Computing and Applications - Milling by mechanical means is vital unit operation in pharmaceutical processing which can be used for controlling particle size reduction. This approach can be... 相似文献
992.
993.
Lubold Nichola Walker Erin Pon-Barry Heather 《User Modeling and User-Adapted Interaction》2021,31(1):35-73
User Modeling and User-Adapted Interaction - Social robots such as learning companions, therapeutic assistants, and tour guides are dependent on the challenging task of establishing a rapport with... 相似文献
994.
Ng GC Freiburger PD Walker WF Trahey GE 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1997,44(1):140-151
Acoustic velocity inhomogeneities in tissue result in aberration of ultrasound images. These aberrations can be modeled as a near field thin phase screen or as a distributed aberrator. The effect of a near field thin phase screen is to time shift the received echo at each element, while distributed aberrators result in both pulse distortions and time shifts from element to element. Most current techniques for the correction of distributed aberrators are limited to application on point targets. A new technique is proposed which uses multiple transmits from spatially shifted transmit apertures (the translating transmit aperture algorithm), in conjunction with phase conjugate filters, to correct for distributed aberrations in the presence of speckle targets. The performance of the translating transmit aperture algorithm in improving the correlation between signals received by elements of different spatial separations is measured, and factors affecting the performance of this technique are investigated in simulation and experiment. 相似文献
995.
Y Reisman GM van Dam CH Gips SM Lavelle B Kanagaratnam P Niermeijer P Spoelstra O de Vries 《Canadian Metallurgical Quarterly》1997,44(17):1367-1375
BACKGROUND/AIMS: In the European Union Euricterus Project on (sub)Icterus proforma, the history and physical examination items were to be used for the physician's working diagnosis (PWD) and 'among others, for the development of the real life data electronic diagnostic tool, Trial. Trial delivers diagnosis probabilities based on Bayes' Theorem (B), completed by Trial Algorithm (TA). We wanted to compare the diagnostic accuracies (PWD and Trial probabilities as a percentage of the final diagnosis (FD) in a patient population) in 3 Dutch databases. METHODOLOGY: The inclusion criteria for both Euricterus and Trial were age > or = 16 and bilirubin > or = 20 mmol/l. Euricterus data gathering took place at the bedside on a proforma with (among other questions) 79 questions on history and physical examination as well as the diagnosis levels for the PWD (1 alternative possible) and FD (17 disease categories, dc). Trial was developed on the data of 7,104 Euricterus patients and its data-entry Demo has the same questions. It calculates the probability of each diagnosis of the 17 dc as a percentage, as each significant finding is encountered (BO, Bayesian Overall). It can simultaneously calculate the resemblance of the patient's signs and symptoms to each disease concomitantly (BV, Bayesian Vertical), and to any subset of a disease. Any probability is further tested for compatibility using TA, a subset of BV, delivering TA-PWD, TA-BO and TA-BV. The Trial test patients came from 3 databases: a Euricterus Dutch Patients Random Sample EDRS (n = 184, internal database) and 2 independent databases: prospective P (n = 80) and retrospective R (n = 152), totalling 416 patients. RESULTS: The accuracies of PWD and Trial showed no differences between the databases, and the results are therefore pooled (n = 416). With testing on the highest probability found, the PWD accuracy was 78%, TA-PWD 81%, TA-BO 74% and TA-BV 72%. The true FD's were mentioned (at any probability) in the PWD in 86%, TA-PWD in 92%, TA-BO in 94% and TA-BV in 91% of the patients. Testing only patients whose FD was "certain" or whose data were without omissions did not improve accuracy. Testing on probability > 95% improved BO and BV accuracy, but not TA-BO or TA-BV. CONCLUSIONS: The Physician's Working Diagnosis accuracy was approximately 80% and did not greatly improve after TA. The Trial TA-BO and TA-BV accuracies were only slightly less than the PWD. For well-trained physicians, Trial strengthens the physician's judgment, and for those less trained (or those to be trained), it delivers a (sub)icterus diagnostic disease probability at nearly consultant level. 相似文献
996.
HM Xu WH Li N Hou SG Zhang HF Li SQ Wang ZY Yu ZJ Li MY Zeng GM Zhu 《Canadian Metallurgical Quarterly》1997,21(9):1013-1022
Thirty-two cases of so-called sclerosing hemangioma of the lung observed by light microscopy were further studied by electron microscopy and/or immunohistochemistry. Three histologic patterns were seen: hemangioma-like, papillary, and solid. The only significant component representing the nature of the lesion is characteristic round cells within the stroma in all these patterns, whereas the surface cells lining the papillary projections or cystic spaces are normal or are hyperplastic bronchioloalveolar cells with a few neuroendocrine cells. Immunohistochemical findings showed that the "stromal cells" (tumor cells) were positive for neuroendocrine markers, namely, chromogranin A (19 of 22 cases), neuron-specific enolase (24 of 24), synaptophysin (six of 10), adrenocorticotropic hormone (14 of 15), growth hormone (14 of 15), calcitonin (11 of 15), and gastrin (11 of 14). Besides, some tumor cells were positive for epithelial membrane antigen (four of four), carcinoembryonic antigen (one of four), and vimentin (one of one). All tumor cells were negative for polyclonal antikeratin antibody (25 cases), AE1 (one case), and AE3 (one case). However, in contrast to the "stromal cells," the surface cells of the cystic spaces stained positively for keratin (25 of 25 cases), AE1 (one of one), AE3 (one of one), epithelial membrance antigen (four of four), and carcinoembryonic antigen (four of four); only a few of them expressed neruoendocrine markers. Both surface and tumor cells were negative for factor VIII-related antigen (25 cases), CD31 (one case), and alpha1-antitrypsin (25 cases). Ten cases further studied by electron microscopy and six examined by ultrastructural morphometry showed that the surface cells were mainly type 2 pneumocytes containing many lamellar bodies in the cytoplasm. Lying among them, neuroendocrine cells were occasionally seen. The stromal tumor cells had no lamellar body, but dense core granules (neurosecretory granules) and microtubules. In six cases, 92.3% (345 of 374) of tumor cells contained neurosecretory granules, which were pleomorphic and 73 to 1056 nm in diameter (mean, 302 nm). Two to 193 (mean, 12) neurosecretory granules were found in each tumor cell. Both immunohistochemical findings and ultrastructural evidence indicate that so-called sclerosing hemangioma of the lung is a benign lesion composed of neoplastic neuroendocrine cells with areas of sclerosis. A suggested name for this tumor is benign neuroendocrine tumor of the lung. The differentiation between this tumor and papillary adenoma, bronchioloalveolar carcinoma, or carcinoid tumor of the lung is discussed. 相似文献
997.
M Mammen IJ Colton JD Carbeck R Bradley GM Whitesides 《Canadian Metallurgical Quarterly》1997,69(11):2165-2170
A plot of absorbance vs 1/time (the "1/time domain") is a more useful representation of the primary data in capillary electrophoresis than traditional plots of absorbance vs time (the "time domain") in a wide set of circumstances, especially when comparing electropherograms in which the rate of electroosmotic flow is not precisely the same. The quantity that is of fundamental interest in capillary electrophoresis (CE) is the electrophoretic mobility of an analyte. The electrophoretic mobility of a species is nonlinearly proportional to time and, therefore, not linearly represented in the time domain: that is, the distance between two peaks along the time axis is not linearly related to the difference in their electrophoretic mobilities. In contrast, the electrophoretic mobility is linearly proportional to 1/time, and the distance between two peaks along the 1/time axis is linearly related to the difference in electrophoretic mobilities. Plots in the 1/time domain are similar to the familiar plots in the time domain (each analyte is represented by a peak, and the order of peaks corresponds to the order in which these analytes reach the detector), but the spacing between the peaks corresponds linearly to differences in mobility. This article derives this useful, visually appealing, and broadly applicable plotting strategy and illustrates common situations in which these plots are more useful than plots in the time domain. 相似文献
998.
This report describes the clinical and histologic features of a pulmonary tumor in a 14-year-old girl that is most consistent with a rare entity described in the literature as "pulmonary endodermal tumor resembling fetal lung" (PET). This tumor is composed of glycogen-rich columnar cells forming complex glands with focal festooning and mitotic activity, admixed with solid "morules" of cells with eosinophilic cytoplasm and focal nuclear clearing. Patchy tumor necrosis and a bland stroma were also present. Immunoreactivity for carcinoembryonic antigen (CEA), alpha 1-antichymotrypsin, and 12E7 was present in glandular cells and for human chorionic gondatropin (HCG), alpha 1-antichymotrypsin, and 12E7 in morular cells. Ultrastructural features are those of an epithelial tumor. Related entities have been called "pulmonary blastoma lacking sarcomatous elements" and "adenocarcinoma of fetal lung type." Most cases of PET have occurred in adults, and the histologic features thought to have prognostic significance in small published series are applied to our case, in which the patient remains well and without evidence of tumor recurrence or metastasis for 28 months following local resection as the sole treatment. 相似文献
999.
HG Garrison GL Foltin LR Becker JL Chew M Johnson GM Madsen DR Miller BH Ozmar 《Canadian Metallurgical Quarterly》1997,1(3):156-162
Recent studies have shown a high frequency of genetic hemochromatosis in the Caucasian population. In addition, the well known organ involvement of genetic hemochromatosis was evident; more than 50% of patients develop a typical arthropathy which may result in severe physical disability. Among approximately 5000 patients referred to the rheumatology outpatient clinics of Bad Nauheim and Frankfurt with different rheumatologic diagnoses, 11 patients with typical signs of hemochromatotic arthropathy were identified. In none of those cases had the diagnosis "genetic hemochromatosis" been previously established. These patients had been treated for rheumatoid arthritis and other rheumatologic disorders over several years. All showed severe organ dysfunction due to iron overload, resulting in a reduced life expectancy. This investigation shows that knowledge of the typical signs of hemochromatotic arthropathy could lead to an earlier diagnosis of genetic hemochromatosis which is necessary to prevent the complications of iron overload in those patients. 相似文献
1000.
Krishnamoorthy AV Woodward TK Goossen KW Walker JA Hui SP Tseng B Cunningham JE Jan WY Kiamilev FE Miller DA 《Applied optics》1997,36(20):4866-4870
We describe a smart-pixel circuit that permits the use of a GaAs/AlGaAs multiple quantum well diode to be used both as a detector for data input and a modulator for data output. The module provides the ability to double the number of inputs or outputs to the array and is well suited to cascaded optoelectronic system architectures that require bidirectional communition. 相似文献