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Logistic regression is a generalized nonlinear regression analysis model and is often used for data mining, automatic disease diagnosis, economic prediction, and other fields. In this paper, we first aimed to introduce the concept of uncertain logistic regression based on the uncertainty theory, as well as investigating the likelihood function in the sense of uncertain measure to represent the likelihood of unknown parameters.

Developing highly efficient earth‐abundant alternatives to traditional noble metal catalysts is essential for clean and sustainable energy‐conversion and energy‐storage technologies, yet still challenging in limited active sites and weak resistance to electrochemical corrosion. Herein, density‐functional theory calculations demonstrate that hexagonal boron nitride (h‐BN), albeit often being considered inert, can generate boron‐active radicals at defective sites by forming heterogeneous structures with graphene‐containing point vacancies, leading to a substantial electron delocalization and charge transfer, indicating a superior catalytic activity. Experimentally, the van der Waals heterostructure is rationally designed with h‐BN nanosheets (BNNs) anchored on reduced graphene oxide (rGO) as strongly coupled composite catalysts. Despite the poor conductivity in BN and lower catalytic activity in rGO, the created heterostructures demonstrate unexpected, improved oxygen evolution reaction (OER) activity with excellent stability in alkaline electrolyte. Qualitative analysis of the valence band offset and theoretical calculation reveal that the formation of heterostructures can significantly drive the electron transfer between C and B atoms near the vacancies across the interface and cause a half‐metallic property of BN, decreasing the free energy barrier of four‐electron OER kinetics. Herein, the synthetic schemes of h‐BNNs are guided as highly active metal‐free OER electrocatalysts.

Abstract Background Cervical cancer is the fourth most common cancer in women. Up to 99% of cervical cancer cases are associated with high-risk human papillomavirus (HPV). Sexual behavior is a direct risk factor for HPV infection, and sexually active college students, therefore, receive attention for HPV vaccination. At present, most Chinese studies lack of in-depth research on influencing factors, and are limited to cervical cancer, HPV, or HPV vaccine, without comprehensive consideration. This study investigated Chinese college students’ cervical cancer prevention and treatment knowledge level, and explored the influencing factors, and understood their willingness to receive HPV vaccination. The findings of this study will lay a foundation for promoting the early screening of cervical cancer and vaccination process. Methods A total of 800 college students from four universities in Zhengzhou, China were selected by multistage random sampling method. A self-administered questionnaire on the knowledge of cervical cancer prevention and treatment, and willingness to receive HPV vaccination was carried out. A logistic regression model was conducted to analyze factors influencing knowledge of cervical cancer prevention and treatment among college students. Results Up to 87.9% of college students said they had heard of cervical cancer. The proportion of college students with good knowledge of cervical cancer prevention and treatment was 46.7%. Logistic regression showed that gender, major, grade, level of education, the father's level of education, premarital sex attitude, and mother cervical cancer screening participation had a significant influence on cervical cancer prevention and treatment knowledge level (P

Enzyme biofuel cells (EBFCs) can convert chemical or biochemical energy in fuel into electrical energy, and therefore have received widespread attention. EBFCs have advantages that traditional fuel cells cannot match, such as a wide range of fuel sources, environmental friendliness, and mild reaction conditions. At present, research on EBFCs mainly focuses on two aspects: one is the use of nanomaterials with excellent properties to construct high-performance EBFCs, and the other is self-powered sensors based on EBFCs. This article reviews the applied nanomaterials based on the working principle of EBFCs, analyzes the design ideas of self-powered sensors based on enzyme biofuel cells, and looks forward to their future research directions and application prospects. This article also points out the key properties of nanomaterials in EBFCs, such as electronic conductivity, biocompatibility, and catalytic activity. And the research on EBFCs is classified according to different research goals, such as improving battery efficiency, expanding the fuel range, and achieving self-powered sensors.

Abstract Background Chronic exposure to diesel exhaust has a causal link to cardiovascular diseases in various environmental and occupational settings. Arterial endothelial cell function plays an important role in ensuring proper maintenance of cardiovascular homeostasis and the endothelial cell dysfunction by circulatory inflammation is a hallmark in cardiovascular diseases. Acute exposure to diesel exhaust in controlled exposure studies leads to artery endothelial cells dysfunction in previous study, however the effect of chronic exposure remains unknown. Results We applied an ex vivo endothelial biosensor assay for serum samples from 133 diesel engine testers (DETs) and 126 non-DETs with the aim of identifying evidence of increased risk for cardiovascular diseases. Environmental monitoring suggested that DETs were exposed to high levels of diesel exhaust aerosol (282.3 μg/m3 PM2.5 and 135.2 μg/m3 elemental carbon). Surprisingly, chronic diesel exhaust exposure was associated with a pro-inflammatory phenotype in the ex vivo endothelial cell model, in a dose-dependent manner with CCL5 and VCAM as most affected genes. This dysfunction was not mediated by reduction in circulatory pro-inflammatory factors but significantly associated with a reduction in circulatory metabolites cGMP and an increase in primary DNA damage in leucocyte in a dose-dependent manner, which also explained a large magnitude of association between diesel exhaust exposure and ex vivo endothelial biosensor response. Exogenous cGMP addition experiment further confirmed the induction of ex vivo biosensor gene expressions in endothelial cells treated with physiologically relevant levels of metabolites cGMP. Conclusion Serum-borne bioactivity caused the arterial endothelial cell dysfunction may attribute to the circulatory metabolites based on the ex vivo biosensor assay. The reduced cGMP and increased polycyclic aromatic hydrocarbons metabolites-induced cyto/geno-toxic play important role in the endothelial cell dysfunction of workers chronic exposure to diesel exhaust.

Carbon nanotube (CNT) fibers have been extensively investigated along the longitudinal direction and are well-known for their high axial tensile strength and modulus. However, after being manufactured into textiles or composites, these fibers are usually subjected to transverse loading during their normal service life. Deformation and failure of CNT fibers induced by external loads in the transverse direction lack examination. This study integrated single-fiber quasi-static and dynamic transverse loading techniques with scanning electron microscopy (SEM) and high-speed imaging, respectively. An extreme condition was considered as the indenter was a sharp razor blade. Failure behavior of single CNT fibers transversely loaded by the blade at different velocities was visualized, and axial mechanical response of these fibers was measured. The fracture surface of CNT fibers was examined by SEM. Additional experimental investigations were performed on commercialized two organic (aramid and ultrahigh molecular weight polyethylene) and two inorganic (ceramic and glass) fibers. It is revealed that CNT fibers experienced initial contact with the blade, followed by partial incision, and ultimately tensile failure. Furthermore, the energy dissipation and dispersion capabilities of CNT fibers per unit mass were demonstrated to surpass that of commercialized high-performance fibers during extreme transverse loading. As the loading rate increased, the energy dissipation of CNT fibers was further improved by 2.1 times. Such high performance of CNT fibers in resisting extreme transverse loading was presumably attributed to the high hardness, strength, and stiffness of CNTs in the transverse direction and weak intermolecular interactions in the axial direction. This study expands material characterization of CNT fibers in the transverse direction and reveals the fundamental failure mechanism of CNT fibers in the harsh environment, which is deemed useful to develop the fiber-scale model for textiles and composites.

High-performance fibers are well-known for their high stiffness and strength under axial tension. However, in their many applications as critical components of textiles and composites, transverse loads widely exist in their normal service life. In this study, we modified a micro material testing system to transverse load single fibers using round-head indenters. By integrating the loading platform with the Scanning Electron Microscopy (SEM) operating at a low-vacuum mode, we visualized the failure processes of fibers without conductive coatings. Post-fracture analysis was conducted to provide complementary information about the fibers’ failure. The energy dissipation was compared with the axial tensile experiments. Three inorganic and two organic fibers were investigated, namely carbon nanotube, ceramic, glass, aramid, and ultrahigh molecule weight polyethylene fibers. Different failure characteristics were reported. It is revealed that the organic fibers had higher energy dissipation than the inorganic fibers under the transverse loading by the round-head indenters. The fiber’s energy dissipation under transverse loading was no more than 17.9% of that subjected to axial tension. Such a reduced energy dissipation is believed to be due to the stress concentration under the indenter. It is suggested that the fiber’s material constituent, structural characteristics, and stress concentration under the indenter should be considered in the fiber model for textiles and composites.