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21.
Shirshova E. P. Mal’tseva A. L. Astashkina O. V. Lysenko A. A. Fomenko Yu. A. 《Fibre Chemistry》2021,53(3):189-193
Fibre Chemistry - The article is devoted to the development of two-layer composites with a fluoroplastic matrix and fiberglass reinforcing elements. The fluoroplastic matrix acts as a protective... 相似文献
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23.
SR Cohen ML Corrigan FL Bookstein CA Trotman A Burdi M Barr 《Canadian Metallurgical Quarterly》1995,6(3):184-189
Trisomy 21 develops as a result of nondisjunction of two homologous chromosomes during either the first or second meiotic division. One of the more important consequences of these genetic alterations is the predictable, although variable disturbance in the architecture of the craniofacial region [1]. Postnatal craniofacial morphology has been extensively studied in Down's syndrome (DS). However, little information is available on human prenatal development of the head and face in such patients. The time at which changes in craniofacial phenotype first emerge in Down's syndrome fetuses and at which physical growth begins to diverge from normal is unknown. To explore these questions, we compared prenatal craniofacial growth in 50 Down's syndrome fetuses with that of 555 fetuses judged to be "typical for body weight and age" using the method of log-linear allometry [2]. 相似文献
24.
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis; however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free; the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma. The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in "blood clot" submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy arises in the placenta and may be more common than reported. 相似文献
25.
To meet the requirements of comprehensively characterizing the morphology of thin films and substrates, a suitable combination of different measuring techniques should be chosen, i.e., a nonoptical surface profile measurement should be used together with optical analysis. It is demonstrated on selected examples of fluoride and oxide films that the use of atomic force microscopy and light scattering fulfills the demand of appropriate quantitative characterization over a sufficiently large range of bandwidths. 相似文献
26.
ML Jensen OM Jensen W Michalski OS Nielsen J Keller 《Canadian Metallurgical Quarterly》1996,23(5):458-463
Superficial leiomyosarcomas are rare tumours. The lesions confined to the dermis, contrary to those involving the subcutis, have been reported to carry a favourable prognosis. A retrospective study of 41 consecutive cases of surgically treated intradermal and subcutaneous leiomyosarcomas was undertaken in order to determine the prognostic factors that may influence the survival of these patients. Seven tumours were predominantly intradermal and 34 involved the subcutaneous tissue. Fifty-four percent of the tumours were located in the lower extremities. All cases stained positively for smooth muscle antigen and 66% for desmin. The tumours were classified with regard to tumour grade I (low grade, 3%), II (intermediate, 12%), IIIA (high grade, 46%) and IIIB (high grade, 39%). In all patients, follow-up information was available. Mean follow-up time was 5 years. The patients with intradermal tumours were all alive without signs of recurrence, whereas 14 of those with leiomyosarcomas involving the subcutis have died with pulmonary metastases. Our study confirms that "pure" intradermal leiomyosarcomas independent of tumour grade behave in a benign fashion, probably due to small tumour size. Tumour size > or = 5 cm, deep localization with fascia involvement, and high malignancy grade (IIIB) were found to deteriorate survival based on a univariate analysis. However, in a multivariate analysis only tumour size was found to be an independent prognostic factor. 相似文献
27.
28.
André Twele Wenxi Cao Simon Plank Sandro Martinis 《International journal of remote sensing》2016,37(13):2990-3004
This article presents an automated Sentinel-1-based processing chain designed for flood detection and monitoring in near-real-time (NRT). Since no user intervention is required at any stage of the flood mapping procedure, the processing chain allows deriving time-critical disaster information in less than 45 min after a new data set is available on the Sentinel Data Hub of the European Space Agency (ESA). Due to the systematic acquisition strategy and high repetition rate of Sentinel-1, the processing chain can be set up as a web-based service that regularly informs users about the current flood conditions in a given area of interest. The thematic accuracy of the thematic processor has been assessed for two test sites of a flood situation at the border between Greece and Turkey with encouraging overall accuracies between 94.0% and 96.1% and Cohen’s kappa coefficients (κ) ranging from 0.879 to 0.910. The accuracy assessment, which was performed separately for the standard polarizations (VV/VH) of the interferometric wide swath (IW) mode of Sentinel-1, further indicates that under calm wind conditions, slightly higher thematic accuracies can be achieved by using VV instead of VH polarization data. 相似文献
29.
An important question for the upcoming Semantic Web is how to best combine open world ontology languages, such as the OWL-based ones, with closed world rule-based languages. One of the most mature proposals for this combination is known as hybrid MKNF knowledge bases (Motik and Rosati, 2010 [52]), and it is based on an adaptation of the Stable Model Semantics to knowledge bases consisting of ontology axioms and rules. In this paper we propose a well-founded semantics for nondisjunctive hybrid MKNF knowledge bases that promises to provide better efficiency of reasoning, and that is compatible with both the OWL-based semantics and the traditional Well-Founded Semantics for logic programs. Moreover, our proposal allows for the detection of inconsistencies, possibly occurring in tightly integrated ontology axioms and rules, with only little additional effort. We also identify tractable fragments of the resulting language. 相似文献
30.
Juan Francisco Gómez-Lopera José Martínez-Aroza Aureliano M. Robles-Pérez Ramón Román-Roldán 《Journal of Mathematical Imaging and Vision》2000,13(1):35-56
This work constitutes a theoretical study of the edge-detection method by means of the Jensen-Shannon divergence, as proposed by the authors. The overall aim is to establish formally the suitability of the procedure of edge detection in digital images, as a step prior to segmentation. In specific, an analysis is made not only of the properties of the divergence used, but also of the method's sensitivity to the spatial variation, as well as the detection-error risk associated with the operating conditions due to the randomness of the spatial configuration of the pixels. Although the paper deals with the procedure based on the Jensen-Shannon divergence, some problems are also related to other methods based on local detection with a sliding window, and part of the study is focused to noisy and textured images. 相似文献