Depression and Sexual Risk Behaviors among Rural-to-urban Migrants in China: The Moderating Roles of Acculturation and Social Capital

Previous studies have documented that depression is positively associated with sexual risk behaviors (SRB) among rural-to-urban migrants. Existing literature has also suggested that acculturation and social capital might moderate this positive relationship. However, data regarding the moderating effects of acculturation and social capital have been inconsistent. The current study aims to examine the relationship between depression and SRB, as well as the moderating roles of acculturation and social capital in this relationship. A sample of 641 young rural-to-urban migrants was recruited through a venue-based sampling approach in Beijing, China. Results indicated that depression was positively associated with SRB. Both acculturation and social capital moderated this relationship, but they showed different moderating effects. Specifically, the level of acculturation was protective against SRB among migrants with a higher level of depression but not among migrants with a lower level of depression. Social capital played a protective role among migrants with a lower level of depression but became a risk factor for those with a higher level of depression. These findings suggested that targeted interventions aiming to reduce depression, improve acculturation stress management skills, and utilize social capital are needed to reduce SRB among rural-to-urban migrants

Bridging the Granularity Gap for Acoustic Modeling

While Transformer has become the de-facto standard for speech, modeling upon the fine-grained frame-level features remains an open challenge of capturing long-distance dependencies and distributing the attention weights. We propose \textit{Progressive Down-Sampling} (PDS) which gradually compresses the acoustic features into coarser-grained units containing more complete semantic information, like text-level representation. In addition, we develop a representation fusion method to alleviate information loss that occurs inevitably during high compression. In this way, we compress the acoustic features into 1/32 of the initial length while achieving better or comparable performances on the speech recognition task. And as a bonus, it yields inference speedups ranging from 1.20$\times$ to 1.47$\times$. By reducing the modeling burden, we also achieve competitive results when training on the more challenging speech translation task.Comment: ACL 2023 Finding

Immunomodulatory roles of metalloproteinases in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, autoimmune pathology characterized by persistent synovial inflammation and gradually advancing bone destruction. Matrix metalloproteinases (MMPs), as a family of zinc-containing enzymes, have been found to play an important role in degradation and remodeling of extracellular matrix (ECM). MMPs participate in processes of cell proliferation, migration, inflammation, and cell metabolism. A growing number of persons have paid attention to their function in inflammatory and immune diseases. In this review, the details of regulation of MMPs expression and its expression in RA are summarized. The role of MMPs in ECM remodeling, angiogenesis, oxidative and nitrosative stress, cell migration and invasion, cytokine and chemokine production, PANoptosis and bone destruction in RA disease are discussed. Additionally, the review summarizes clinical trials targeting MMPs in inflammatory disease and discusses the potential of MMP inhibition in the therapeutic context of RA. MMPs may serve as biomarkers for drug response, pathology stratification, and precision medicine to improve clinical management of rheumatoid arthritis

Enhanced entanglement and output squeezing in electro-optomechanical system with an optical parametric amplifier

We investigate the entanglement phenomena, assisted by an electro-optical hybrid system with an optical parametric amplifier. The system consists of one mechanical oscillator that is coupled to another oscillator via a Coulomb force and also to an optical cavity via an optomechanical interaction. If the coupling between the cavity field and the optical parametric amplifier and between the two mechanical oscillators is suitable, the system exhibits the phenomena of stationary entanglement. Specifically, the entanglement is strongly affected by the parameter gain and the Coulomb interaction, and larger parameter gain and stronger Coulomb coupling induce an increasing amount of entanglement. We also study the output squeezing, and the results reveal that the output entanglement is affected by the resonator frequency, the parameter gain, and the Coulomb coupling

Exceptional cryogenic tensile properties of K4169 superalloy by micro-grain casting process

The simultaneous provision of strength and ductility of casting superalloy is challenging. In this work, a micro-grain casting process was applied to produce grain-refined K4169 alloy, which exhibited a superior combination of tensile ultimate strength, yield strength and elongation of 1204 MPa, 1041 MPa and 21.0 % at 23 °C. The tensile strengths were significantly enhanced without elongation weakened compared with the conventional casting one, which exhibited values of 947 MPa, 813 MPa and 20.0 %, respectively. As temperature decreased to −196 °C, the elongation of micro-grain K4169 further increased to 26.1 % while decreased to 13.5 % of the conventional one resulting from the different twinning tendencies related to grain refinement. This is because twinning occurs predominantly in grains orientated close to the 〈111〉 // tensile axis, and micro-grain casting process improves the probability for grains to meet this crystallography condition. The deformation twins together with stacking faults and Lomer-Cottrell locks ensured continuous work hardening, resulting in the delayed onset of necking and a better elongation. This work highlights the excellent mechanical properties of micro-grain K4169 and anticipates its enormous application potential. Moreover, the results of micromechanical behavior-microstructure-property relationship may improve the understanding of the plastic deformation of K4169 alloy and guide a further upgrading

Effect of Cooling Rate on the Microstructure and Mechanical Property of Nickel-Based Superalloy MAR-M247

Heat treatment is an important process for optimizing the microstructures of superalloys, and the cooling rate after solid solution treatment is one of the most critical parameters. In this work, we treated solid solution MAR-M247 alloys with water quenching, air cooling, and furnace cooling. Microstructure characterization, hardness, and room temperature tensile tests were conducted to investigate the effect of cooling rate on the microstructure and mechanical properties of MAR-M247 alloys. The results showed that the cooling rate after solid solution treatment mainly affected the precipitation behavior of the secondary γ′ phase, but it had few effects on other microstructure characterizations, including grain size, γ/γ′ eutectic, and MC carbide. The water-quenched sample had the highest cooling rate (400 °C/s) and hardness (400 HV) but suffered from premature fracture because of quenching cracks. A further decrease in cooling rate from 1.5 °C/s to 0.1 °C/s deteriorated hardness (384 HV to 364 HV) and yield strength (960 MPa to 771 MPa) but increased elongation (8.5% to 13.5%). Moreover, the deformation mechanism was transformed from dislocation shearing to Orowan bypassing. The decreased yield strength was mainly due to the weakened precipitation strengthening resulting from γ′-phase coarsening. The improved elongation was attributed to not only the higher work-hardening index caused by interface dislocation networks but also the more uniform deformation, which delayed necking

Saturated Resin Ectopic Regeneration by Non-Thermal Dielectric Barrier Discharge Plasma

Textile dyes are some of the most refractory organic compounds in the environment due to their complex and various structure. An integrated resin adsorption/Dielectric Barrier Discharge (DBD) plasma regeneration was proposed to treat the indigo carmine solution. It is the first time to report ectopic regeneration of the saturated resins by non-thermal Dielectric Barrier Discharge. The adsorption/desorption efficiency, surface functional groups, structural properties, regeneration efficiency, and the intermediate products between gas and liquid phase before and after treatment were investigated. The results showed that DBD plasma could maintain the efficient adsorption performance of resins while degrading the indigo carmine adsorbed by resins. The degradation rate of indigo carmine reached 88% and the regeneration efficiency (RE) can be maintained above 85% after multi-successive regeneration cycles. The indigo carmine contaminants were decomposed by a variety of reactive radicals leading to fracture of exocyclic C=C bond, which could cause decoloration of dye solution. Based on above results, a possible degradation pathway for the indigo carmine by resin adsorption/DBD plasma treatment was proposed

Study on the quenching sensitivity of corrosion properties in 7199 aluminum alloy

This study used electrochemical corrosion, intergranular corrosion (IGC), and exfoliation corrosion tests, as well as microscopic observations of the microstructure and first-principles calculations, to investigate the effect of different quenching rates on the microstructure and corrosion properties of the 7199 alloy. The results show that as the quenching rate decreases, the size, Zn, and Mg content of precipitated phases at grain boundaries (GBs), as well as the width of the precipitation-free zone (PFZ), increase, resulting in a decrease in corrosion properties. During slow quenching, the η phase (MgZn2) at the GBs continuously absorbs surrounding Zn and Mg atoms, causing Zn and Mg atom depletion near the GBs. This results in the formation of a wide PFZ. Enlargement of the η phase and PFZ at the GBs leads to anodic dissolution channels, allowing for rapid corrosion expansion along the GBs. Additionally, at slow quenching rates, not only does the η phase precipitate at the subgrain boundaries (SGBs) but also the T and S phases. In corrosive environments, the η phase is more prone to corrosion than the T and S phases. Electron work function calculations show that the S phase has the highest corrosion potential, whereas the η phase has the lowest. As a result, SGBs containing T and S phases are unlikely to serve as corrosion pathways. Corrosion preferentially extends along SGBs containing η phases

Research progress on dimensional accuracy control technologies of complex thin-walled superalloy investment castings for aero-engines

Superalloys are predominantly employed to crucial aviation hot-end components such as turbine rear casings，diffusers，and pre-swirl nozzles. The investment casting technology supersedes “casting + welding” forming approaches，which reduces the number of parts and processing procedures，offers improved reliability and mass reduction. Therefore，investment casting is a pivotal technology for aviation component manufacturing. However，the casting of complex thin-walled components encounters challenges with dimensional accuracy，impacting engine aerodynamic performance and assembly precision，which has become a bottleneck problem restricting the manufacturing quality of key structural components of aero-engines in China for a long time. This article reviews the current advancement in the dimensional accuracy control for superalloy investment castings at home and abroad. A forward-looking analysis and discussion on development trends are conducted，particularly focusing on digital and intelligent technologies. There is an urgent need to build a digital twin platform for investment casting in the future and to develop more advanced accurate，quantitative and intelligent prediction methods for dimensional deformation and die profile design theory