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关键词： Shape coefficient   Polyester   Cotton   Image processing   Shape recognition  

摘要： As of today, it still remains a considerable challenge to identify the polyester/cotton fiber category in the textile industry. Based on shape coefficient analysis, a novel comprehensively-designed and appropriately-developed digital cross-section image processing method was proposed to improve the identification accuracy of polyester/cotton fiber. A self-developed microscope image acquisition system was established, so as to digitalize the cross section of fiber. Aimed at the gray scale enhancement, binarization and opening operation, a set of image preprocessing algorithms was developed. Initially, the edge detection algorithm was used to identify the external contour of the cross-section of fiber. Subsequently, the cross section of fiber was separated by watershed segmentation algorithm, and that, the false fiber was removed by area elimination algorithm. Finally, the shape coefficient was calculated to identify polyester/cotton fiber category. The experimental results indicated that the data and results obtained by the newly-designed digital analysis method which is based on shape coefficient in this paper can be used to identify the polyester/cotton fiber category, showing a broad application prospect in textile quality control, including the developments of concerned equipments, methods and standards.

关键词： Questions   Categorial approaches   Short answers   Quantificational variability   Multi-wh questions   Question coordinations   Free relatives   wh-conditionals   Mention-some   wh-indefinites  

摘要： This paper revisits two fundamental issues in question semantics-what does a question mean, and how is this meaning compositionally derived? Drawing on observations with the distribution of wh-words in questions and free relatives as well as quantificational variability effects in question-embeddings, I argue that the nominal meanings of short answers must be derivable from question denotations, which therefore calls for a categorial approach to defining questions, including embedded questions. I provide a novel hybrid categorial approach to compose questions. This approach overcomes the problems with traditional categorial approaches in defining bare wh-indefinites, composing multi-wh questions, and accounting for coordinations of questions.

关键词： Brauer–   Picard group   Finite tensor category   Symmetric monoidal category   Cohomology groups  

摘要： In the preceeding paper we constructed an infinite exact sequence a la Villamayor-Zelinsky for a symmetric finite tensor category. It consists of cohomology groups evaluated at three types of coefficients which repeat periodically. In the present paper we interpret the middle cohomology group in the second level of the sequence. We introduce the notion of coring categories and we obtain that the mentioned middle cohomology group is isomorphic to the relative group of Azumaya quasi coring categories. This result is a categorical generalization of the classical Crossed Product Theorem, which relates the relative Brauer group and the second Galois cohomology group with respect to a Galois field extension. We construct the colimit over symmetric finite tensor categories of the relative groups of Azumaya quasi coring categories and the full group of Azumaya quasi coring categories over vec. We prove that the latter two groups are isomorphic.

关键词： benign lesions   BI‐   RADS 4C   BI‐   RADS 5   breast   fine‐   needle aspiration   ultrasound guided  

摘要： Background The purpose of this study was to determine the pathological and ultrasound (US) features of benign nonpalpable breast lesions (NPBLs) classified as Breast Imaging Reporting and Data System (BI-RADS) category 4C or 5. Methods Between 2003 and 2007, 849 consecutive NPBLs detected at US and classified as BI-RADS category 4C (505) or 5 (344) initially underwent US-guided fine needle aspiration (FNA) at our institution. Benign diagnoses were established according to surgical excision findings or during a minimal 6-month imaging follow-up (mean, 3.7 years [SD, 2.6 years]). US BI-RADS features were reviewed and compared retrospectively using a chi-square test for the following pathological categories: epithelial and fibrous proliferation (EFP), cystic and papillary lesion (C&P), inflammatory lesion (IL), benign tumor (BT), intramammary lymph node (ILN), intraepithelial proliferative lesion (IPL), and nonspecific morphological alteration (NMA). The performance of FNA in the diagnosis of benignity was assessed. Results Of 849 NPBLs, 110 (12.9%) NPBLs were benign: 88 (17.4%) were BI-RADS category 4C, and 22 (6.4%) were BI-RADS category 5. Forty-four (40%) were EFPs, 21 (19%) were C&Ps, 13 (12%) were NMAs, 11 (10%) were ILs, 11 (10%) were BTs, 8 (7%) were IPLs, and 2 (2%) were ILNs. Lesion shape, US pattern distribution, and posterior features showed statistically significant differences between these categories (P < .05): 33 (75%) EFPs exhibited posterior shadowing, 18 (86%) C&Ps were homogenous, 9 (82%) ILs were heterogeneous, 11 (100%) BTs were homogeneous, 9 (82%) BTs were oval, and 6 (75%) IPLs were irregularly shaped. Of the 110 benign NPBLs, FNA diagnosis was falsely positive in 7 (6%), suspicious in 10 (9%), and benign in 90 (82%), and 3 (3%) were inadequate for diagnosis. Conclusion A diverse array of benign NPBLs can be classified as BI-RADS category 4C or 5 on US, each showing specific imaging presentations.

关键词： Liver neoplasms   Prognosis   Magnetic resonance imaging   Positron emission tomography computed tomography  

摘要： Objectives To evaluate the postoperative prognostic value of the Liver Imaging Reporting and Data System (LI-RADS) category on gadoxetic acid-enhanced MRI and 18F-fluorodeoxyglucose PET-CT in patients with primary liver carcinomas (PLCs). Methods A total of 189 patients with chronic liver disease and surgically proven single PLC (42 intrahepatic cholangiocarcinomas and 21 combined hepatocellular-cholangiocarcinomas and 126 hepatocellular carcinomas [2:1 matching to non-HCC malignancies]) were retrospectively evaluated with gadoxetic acid-enhanced MRI and PET-CT. Two independent reviewers assigned an LI-RADS category for each observation. The tumor-to-liver standardized uptake value ratio (TLR) was calculated. The overall survival (OS), recurrence-free survival (RFS), and the associated factors were evaluated. Results In multivariable analysis, LI-RADS category (LR-4 or LR-5 [LR-4/5] vs. LR-M;OS, hazard ratio [HR] 2.24, p = 0.006;RFS, HR 1.61, p = 0.028) and TLR (low, < 2.3 vs. high, >= 2.3;OS, HR 2.09, p = 0.014;RFS, HR 2.17, p < 0.001) were the independent factors for OS and RFS. For the LR-M group, the high TLR group showed lower OS and RFS rates than the low TLR group (OS, p = 0.008;RFS, p < 0.001). For the LR-4/5 group, the OS and RFS rates were not significantly different between the high TLR and low TLR groups (both p > 0.05). Conclusions Both LI-RADS category on MRI and TLR on PET-CT are associated with the postoperative prognosis of PLCs. The prognosis of PLCs classified as LR-M can be further stratified according to the TLR group, but not for the PLCs classified as LR-4/5.

关键词： additive rates model   cystic fibrosis   multiple event type   proportional rates model   Pseudomonas aeruginosainfections  

摘要： Modeling recurrent event data with multiple event types has drawn interest in recent biomedical studies due to its flexibility for understanding different risk factors for multiple recurrent event processes. However, in such data type, missing event type appears frequently because of various reasons such as recording ignorance or resource limitation. In this study, we aim to propose an inverse probability weighted estimation that is commonly used in the missing data literature to correct possibly biased estimation by a complete-case analysis. This approach is not limited to a specific form of the recurrent event model. We derive the large sample theory in a general form. We demonstrate that our approach can be applied to either multiplicative or additive rates model with practical sample size via comprehensive simulations. Nonmucoid and mucoid Pseudomonas aeruginosa infections of 14 888 patients in 2016 Cystic Fibrosis Foundation Patient Registry data are analyzed to show that, without including 12% events with missing event type in the analysis, several factors may be misidentified as risk factors for the nonmucoid type of infections.

关键词： Failure tuyere   large blast furnace   erosion   pitting   cracking   bending   breakage mechanism   copper  

摘要： The tuyere is an important item of equipment for a blast furnace. However, the tuyere life of the large blast furnace can be quite short. The failure of tuyere will seriously affect the production of a blast furnace. So, it is of great significance to carry out experimental research on any damaged tuyere with a view to extending its service life. The damaged tuyere from a 5800m(3)blast furnace in China was analyzed by SEM, EDS and optical microscope. According to the results of microscopic phase analysis, the tuyere failure types are defined and classified. It is found that the tuyere failure types of the large blast furnace are mainly divided into four categories: erosion, pitting, cracking and bending. The high-temperature slag-iron repeatedly bonding and peeling off from the tuyere is the main cause of tuyere damage. Finally, the failure mechanism of different types of damaged tuyere is analyzed.

关键词： natural Abs   glycan-dependent Ab binding   HIV-1 Env glycans   SARS-CoV-2 spike glycans   Fab dimerization   FDG Abs   marginal zone B cells   IgM-memory B cells  

摘要： Natural antibodies (Abs) can target host glycans on the surface of pathogens. We studied the evolution of glycan-reactive B cells of rhesus macaques and humans using glycosylated HIV-1 envelope (Env) as a model antigen. 2G12 is a broadly neutralizing Ab (bnAb) that targets a conserved glycan patch on Env of geographically diverse HIV-1 strains using a unique heavy-chain (VH) domain-swapped architecture that results in fragment antigen-binding (Fab) dimerization. Here, we describe HIV-1 Env Fab-dimerized glycan (FDG)-reactive bnAbs without VH-swapped domains from simian-human immunodeficiency virus (SHIV)-infected macaques. FDG Abs also recognized cell-surface glycans on diverse pathogens, including yeast and severe acute respiratory syndrome coronavirus 2 (SARS-CoV- 2) spike. FDG precursors were expanded by glycan-bearing immunogens in macaques and were abundant in HIV-1-naive humans. Moreover, FDG precursors were predominately mutated IgM(+) IgD(+)CD27(+), thus suggesting that they originated from a pool of antigen-experienced IgM(+) or marginal zone B cells.

关键词： Anomaly detection   Categorical data   Gaussian process   Data-efficient learning  

摘要： We propose a semi-supervised approach towards anomaly detection in multivariate categorical data. Our goal is to learn a model that can distinguish the anomalous data, given a small set of training data from the normal class. To this end, our approach learns the probability distribution of normal instances with the assumption that the categorical data are generated from a continuous latent space. Gaussian process is adopted to construct the generative model. As a non-parametric Bayesian model, Gaussian process can adapt its model complexity according to the data size. Hence, our approach can be effective when the training dataset is small. Comprehensive experiments over different benchmarks clearly demonstrate the effectiveness of our approach. (c) 2021 Elsevier B.V. All rights reserved.