Multiple Human Papillomavirus Infections among Chinese Women with and without Cervical Abnormalities: A Population-Based Multi-Center Cross-Sectional Study

Background: Despite an increase in the number of studies conducted in recent years on human papillomavirus (HPV) and cervical cancer epidemiology, the profile of multiple HPV infections remain obscure, particularly among Chinese women. During 2004–2005, a series of population-based HPV prevalence surveys were performed by Cancer Institute and Hospital of Chinese Academy of Medical Sciences (CIHCAMS) and International Agency for Research on Cancer (IARC). Based on these surveys, we evaluated the prevalence and risk factors of multiple HPV infections, and explored its association with cervical abnormalities among Chinese women. Methods: A total of 2374 women from three study centers underwent gynecological examinations with valid cytology and their HPV results were included in the analysis. Forty-four HPV types were detected using the GP5+/6+ PCR-based enzyme immunoassay. An unconditional logistic regression model was used to evaluate the effect of multiple HPV infections on cervical lesions and its risk factors adjusting for confounders. The between-groups difference was evaluated by a heterogeneity test based on the Q test. Results: One hundred and eleven women of multiple HPV infections was found among 2374 Chinese women with a prevalence of 5.28% (95% CI = 3.86–5.60%), which attributed to 28.98% (95% CI = 24.49–33.81%) of all of the 383 HPV-positive women. A significantly increased risk of multiple HPV infections was found in the older women (≥45 years; adjusted OR = 1.52, 95% CI = 1.02–2.27) and those having more than three sexual partners (adjusted OR = 2.10, 95% CI = 1.05–4.17) after adjustment for age-group, study area, and number of sexual partner. We also found that the risk of high-grade lesions was significantly higher than that of low-grade lesions with the multiple HPV infections (Pheterogeneity = 0.044), but not as significantly with the single HPV infection (Pheterogeneity = 0.108). Conclusion: Multiple HPV Infections, especially with high-risk HPV types, may be a substantial indicator either for public cervical cancer prevention or clinical implications

Memory-Gated Recurrent Networks

The essence of multivariate sequential learning is all about how to extract dependencies in data. These data sets, such as hourly medical records in intensive care units and multi-frequency phonetic time series, often time exhibit not only strong serial dependencies in the individual components (the "marginal" memory) but also non-negligible memories in the cross-sectional dependencies (the "joint" memory). Because of the multivariate complexity in the evolution of the joint distribution that underlies the data generating process, we take a data-driven approach and construct a novel recurrent network architecture, termed Memory-Gated Recurrent Networks (mGRN), with gates explicitly regulating two distinct types of memories: the marginal memory and the joint memory. Through a combination of comprehensive simulation studies and empirical experiments on a range of public datasets, we show that our proposed mGRN architecture consistently outperforms state-of-the-art architectures targeting multivariate time series.Comment: This paper was accepted and will be published in the Thirty-Fifth AAAI Conference on Artificial Intelligence (AAAI-21

Optimization of Combined Casing Treatment Structure Applied in a Transonic Axial Compressor Based on Surrogate Model

For modern high load compressors, an excellent stability-enhancing capability by casing treatment (CT) is desirable. However, it is very time consuming to accomplish effective CT design. In this study, a new combined CT structure composed of axial skewed slots and end-wall injection, was proposed to be installed in transonic axial compressors to improve the overall performance. Considering the high computation cost for CFD simulation of the flow field in transonic compressor, a Gaussian Process Regression (GPR) surrogate model combined with Latin hypercube sampling, was utilized to predict compressor performance. For optimization process, a multi-objective evolutionary algorithm (NSGA-Ⅱ) was adopted to obtain the Pareto-optimal front. The main geometric parameters of the slot and the mass-flow rate of injection were selected as design parameters, with the peak efficiency and pressure ratio being two objectives. The results indicated that the surrogate model works well in capturing the key features of the concerning target and accelerating the optimization process. The optimal scheme of the combined CT was found able to increase stall margin (SM) by 19.5% with low efficiency penalty, showing a better performance than the reference combined casing treatment (CCT) scheme. What’s more, the analysis results of entropy generation showed that the superior effect of optimized scheme (OPT) can be attributed to the improvement of exchange flow in slots and the decreased loss in the whole passage

Retinal Fundus Image Registration via Vascular Structure Graph Matching

Motivated by the observation that a retinal fundus image may contain some unique geometric structures within its vascular trees which can be utilized for feature matching, in this paper, we proposed a graph-based registration framework called GM-ICP to align pairwise retinal images. First, the retinal vessels are automatically detected and represented as vascular structure graphs. A graph matching is then performed to find global correspondences between vascular bifurcations. Finally, a revised ICP algorithm incorporating with quadratic transformation model is used at fine level to register vessel shape models. In order to eliminate the incorrect matches from global correspondence set obtained via graph matching, we proposed a structure-based sample consensus (STRUCT-SAC) algorithm. The advantages of our approach are threefold: (1) global optimum solution can be achieved with graph matching; (2) our method is invariant to linear geometric transformations; and (3) heavy local feature descriptors are not required. The effectiveness of our method is demonstrated by the experiments with 48 pairs retinal images collected from clinical patients

Phase separation and enhanced wear resistance of Cu88Fe12 immiscible coating prepared by laser cladding

In order to eliminate the microstructure segregation of Cu–Fe immiscible alloys which characterized with a liquid miscible gap, the Cu88Fe12 (wt.%) immiscible coating was prepared by laser cladding. The phase separation characteristic and wear resistance of the Cu88Fe12 (wt.%) immiscible coating were also investigated. The results show that the size of the milled Cu88Fe12 composite powder is reduced comparing to that of the un-milled powder due to fracturing during mechanical milling. Moreover, the demixing or delamination disappears in the Cu88Fe12 immiscible coating and a large amount of face-centered-cubic (fcc) γ-Fe and body-centered-cubic (bcc) α-Fe particles are dispersed in the face-centered-cubic (fcc) ɛ-Cu matrix as a result of liquid phase separation. The size of Fe-rich particles presents an increasing tendency from the bottom to the top of the immiscible coating. As a result, the microhardness of the immiscible coating is improved compared with brass (∼138 HV0.2) due to the presence of high-hardness Fe-rich particles (∼191 HV0.2) and the solid solution strengthening effect of Fe in Cu-rich matrix. Furthermore, the width of ploughing, the width and height of wear scar on the surface of the immiscible coating are much less than those on the surface of brass. Therefore, the wear resistance of the immiscible coating is remarkably enhanced compared with brass

Periodic scheduling for MARTE/CCSL: Theory and practice

International audienceThe UML profile for Modeling and Analysis of Real-Time and Embedded systems (MARTE) is used to design and analyze real-time and embedded systems. The Clock Constraint Specification Language (ccsl) is a companion language for MARTE. It introduces logical clocks as first class citizens as a way to formally specify the expected behavior of models , thus allowing formal verification. ccsl describes the expected infinite behaviors of reactive embedded systems. In this paper we introduce and focus on the notion of periodic schedule to allow for a nice finite abstraction of these infinite behaviors. After studying the theoretical properties of those schedules we give a practical way to deal with them based on the executable operational semantics of ccsl in rewriting logic with Maude. We also propose an algorithm to find automatically periodic schedulers with the proposed sufficient condition, and to perform formal analysis of ccsl constraints by means of customized simulation and bounded LTL model checking