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Interface strength, damage and fracture properties between ceramic films and metallic substrates affect the service reliability of related parts. The films’ thickness, grain size and residual stress affect the interface properties and fracture behavior, thus related studies attract great attention. In this paper, the interface damage evolution and fracture behavior between ceramic films and metallic substrates were simulated by developing a three dimensional finite element model of alumina films on Ni substrates with cohesive elements in the interfaces. The interface fracture energy as a key parameter in the simulation was firstly determined based on its thermodynamic definition. The simulation results show the Mises stress distribution and damage evolution of the film/substrate structures during uniaxial tensile loading. Specially, when grain size of the films is in nanoscale, the interface strength increases obviously, agreeing with the previous experimental results. The effects of residual stress on interface properties was further simulated. The interface strength was found to decrease with increasing radial residual force and the axial residual pressure increases the interface strength. When the thickness of the films increases, the interface strength keeps a constant but the speed of interface damage becomes faster, that is, the thicker films show catastrophic fracture. The underlying mechanism of damage speed was analyzed. Understanding these size effects and the effects of residual stress is helpful to guide the design of related parts.

Summary The accumulation of giant lipid droplets (LDs) increases the risk of metabolic disorders including obesity and insulin resistance. The lipolysis process involves the activation and transfer of lipase, but the molecular mechanism is not completely understood. The translocation of ATGL, a critical lipolysis lipase, from the ER to the LD surface is mediated by an energy catabolism complex. Oxysterol-binding protein-like 2 (OSBPL2/ORP2) is one of the lipid transfer proteins that regulates intracellular cholesterol homeostasis. A recent study has proven that Osbpl2−/− pigs exhibit hypercholesterolemia and obesity phenotypes with an increase in adipocytes. In this study, we identified that OSBPL2 links the endoplasmic reticulum (ER) with LDs, binds to COPB1, and mediates ATGL transport. We provide important insights into the function of OSBPL2, indicating that it is required for the regulation of lipid droplet lipolysis., Graphical Abstract, Highlights • LD lipolysis is impaired in OSBPL2/osbpl2b-mutant HepG2 cells and zebrafish • OSBPL2 interacts with COPB1, a subunit of the COPI complex located on LDs • Altered COPI complexes on LDs may perturb the trafficking of lipolysis lipase ATGL, Biological Sciences; Cell Biology; Molecular Biology

The fast continuous rotation scanning mode is suitable for situations when a higher scanning speed or a lower radiation dose is required for micro-CT. Under this scanning mode, the specimen rotates far beyond 2π, but not an integral multiple of 2π continuously while the detector collects projection images at a high frame frequency, which consequently produces uneven-distributed and redundant projections with a high level of noise. Therefore, for subsequent three-dimensional (3D) image reconstruction, each 2π-projection view during a whole rotation span must be accurately located, and image denoising is an essential pre-processing step for improving quality of reconstructed images. For matching the rotation angle with the projection image accurately under the fast continuous rotation scanning mode, a structure similarity (SSIM) coefficient was used as a control parameter for extraction of periodic projection sequences for 3D reconstruction. Meanwhile, an improved non-local means (NL-means) algorithm was proposed for noise reduction in projection sequences, and a graphic processing unit (GPU) capable of highly parallel and fast floating-point calculation was used for alleviating the computation cost of the algorithm. The experimental results show that the SSIM-based 2π-projection-view locating method is highly accurate in identifying periodic projection sequences and is easy to implement, and that the improved NL-means algorithm can well restrain the quantum noise while preserving detailed information.

Beam structures with partially covered plates have been widely used in macro members and micro devices, such as concrete beams with fiber-reinforced plastic (FRP) plates, aircraft structures with FRP patches and smart beams with actuators/sensors. Based on the two-parameter elastic foundation model and the classical Euler–Bernoulli beam model, a rigorous analytical solution of interfacial stresses and overall stiffness of plated beams is obtained, and influences of the interface and plate properties are presented. The limitation of the assumption of the same curvature of host beam and plate, which was widely adopted in previous studies, has been clarified. And the present solution is applicable to a wider range of interface and plate properties, especially for large values of plate thickness, plate modulus and interfacial stiffness, as well as small values of plate length. The saturation phenomenon of overall stiffness is observed in some cases, and critical values of the interface and plate parameters corresponding to the saturation limit of overall stiffness can be referred for design. The results can provide guidance for the optimal design of widely-used plated beams to prevent premature interfacial debonding and acquire better overall performance, such as higher stiffness with FRP plates or shape control with actuators, by manipulating the interface and plate properties.

Calcium carbonate nanomaterials (nano-CaCO3) are widely used in both manufacturing and consumer products, but their potential health hazards remain unclear. The objective of this study was to survey workplace exposure levels and health effects of workers exposed to nano-CaCO3. Personal and area sampling, as well as real-time and dust monitoring, were performed to characterize mass exposure, particle size distribution, and particle number exposure. A total of 56 workers (28 exposed workers and 28 unexposed controls) were studied in a cross-sectional study. They completed physical examinations, spirometry, and digital radiography. The results showed that the gravimetric nano-CaCO3 concentration was 5.264 ± 6.987 mg/m3 (0.037–22.192 mg/m3) at the workplace, and 3.577 ± 2.065 mg/m3 (2.042–8.161 mg/m3) in the breathing zone of the exposed workers. The particle number concentrations ranged from 8193 to 39 621 particles/cm3 with a size range of 30–150 nm. The process of packing had the highest gravimetric and particle number concentrations. The particle number concentration positively correlated with gravimetric concentrations of nano-CaCO3. The levels of hemoglobin, creatine phosphokinase (CK), lactate dehydrogenase, and high-density lipoprotein cholesterol (HDL-C) in the nano-CaCO3 exposure group increased significantly, but the white blood cell count (WBC), Complement 3 (C3), total protein (TP), uric acid, and creatinine (CREA) all decreased significantly. The prevalence rate of pulmonary hypofunction was significantly higher (p = 0.037), and the levels of vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC, peak expiratory flow and forced expiratory flow 25% (FEF 25%), FEF 25–75% were negatively correlated with gravimetric concentrations of nano-CaCO3 (p 3 exposure level was associated with pulmonary hypofunction (p = 0.005). Meanwhile, a dose-effect relationship was found between the accumulated gravimetric concentrations of nano-CaCO3 and the prevalence rate of pulmonary hypofunction (p = 0.048). In conclusion, long-term and high-level nano-CaCO3 exposure can induce pulmonary hypofunction in workers. Thus, lung function examination is suggested for occupational populations with nano-CaCO3 exposure. Furthermore, future health protection efforts should focus on senior workers with accumulation effects of nano-CaCO3 exposure.

Summary Early work on call centers focused on opinion collection, and service acceptance used manual entry to record text information for incoming calls and to count various types of calls. With the development of text mining technologies, it is possible for call centers to become information providers. Although traditional text mining methods have been well studied, no algorithm has been designed specifically for call center data, which contains structured information about the call center in addition to plain text. A telephone call usually has several properties such as caller number, call time, and so on. Aiming at the data characteristics of call centers, in this paper, we propose an improved latent Dirichlet allocation (LDA) model called A-LDA, which includes information from external-related attributes and is suitable for building topic mining models for call centers. We present a Gibbs sampling-distributed computing implementation for our model's inferences and use datasets from China Central Television telephone call center to perform an experiment on topic detection. The results show that A-LDA, which uses external correlation properties, has a lower perplexity value and a better generalization performance than the traditional LDA method and can find topics associated with values contained by the external attributes. Copyright © 2016 John Wiley & Sons, Ltd.