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Variable stiffness mechanisms have become popular for improving the performance of meso/microscale robots due to their ability to enable safe, effective, and versatile operation without additional actuators. In minimally invasive surgery (MIS), they can provide low stiffness for adaptability and an extended workspace and high stiffness for stable manipulation. This study aims to optimize the pattern design that maximizes the stiffness ratio while preventing buckling. Longitudinal slits were identified as the ideal shape for maximizing the ratio using topology optimization. The effects of the design parameters were investigated by analytical modeling and finite element analysis (FEA). Finally, we established a design optimization process to maximize the variable stiffness ratio while ensuring safety. The load and buckling tests of 19 cases were verified in both the experiment and FEA. Buckling occurred in eight cases, consistent with the expected results from the proposed map. Among the tested cases, the tube with the optimal pattern parameter set exhibits the highest stiffness ratio of 2.67 while satisfying the given stiffness constraint (greater than 0.3 times the flexural stiffness of the initial tube) and avoiding buckling. The proposed optimization method potentially enables an extended workspace and more versatile functionality for MIS instruments.

Ferroptosis, a type of cell death induced by lipid peroxidation, has emerged as a novel anti-cancer strategy. Cancer cells frequently acquire resistance to ferroptosis. However, the underlying mechanisms are poorly understood. To address this issue, we conducted a thorough investigation of the genomic and transcriptomic data derived from hundreds of human cancer cell lines and primary tissue samples, with a particular focus on non-small cell lung carcinoma (NSCLC). It was observed that mutations in Kelch-like ECH-associated protein 1 (KEAP1) and subsequent nuclear factor erythroid 2-related factor 2 (NRF2, also known as NFE2L2) activation are strongly associated with ferroptosis resistance in NSCLC. Additionally, AIFM2 gene, which encodes ferroptosis suppressor protein 1 (FSP1),was identified as the gene most significantly correlatedwith ferroptosis resistance, followed by multiple NRF2 targets. We found that inhibition of NRF2 alone was not sufficient to reduce FSP1 protein levels and promote ferroptosis, whereas FSP1 inhibition effectively sensitized KEAP1-mutant NSCLC cells to ferroptosis. Furthermore, we found that combined inhibition of FSP1 and NRF2 induced ferroptosis more intensely. Our findings imply that FSP1 is a crucial suppressor of ferroptosis independent of NRF2 and that synergistically targeting both FSP1 and NRF2 may be a promising strategy for overcoming ferroptosis resistance in cancer.

This study analyses the affectivity of social disgust behind the oppressive exclusion of social minorities, such as the forced institutionalisation of vagrants in modern Korean society. This social exclusion of vagrants is divided into two forms: the forced institutionalisation of ‘infected vagrants’ during the Japanese occupation and the forced institutionalisation of ‘vagrants themselves’ during the developmental state. In both cases, the visible power apparatus of exclusion of minorities was socially legitimised by the effective use of disgust politics of purification and isolation. Through this analysis, this study joins the discourse on affective communities as a critical alternative to deinstitutionalisation by revealing the dynamics of the social disgust that threatens the community’s existence.

This paper aims to identify and understand factors affecting insiders' intention to disclose patients' medical information and to investigate how these factors affect the intention to disclose. Based on the literature review on deterrence theory and health information security awareness (HISA), we identify relevant factors and develop a research model explaining insiders' intention to disclose patients' health information. We collect data (N = 105) through scenario-based experiments. Results show that two personal factors, collectivism, and IT proficiency, play a significant role in the model. While collectivism affects two components (health information security regulation awareness and punishment severity awareness) of HISA which influences intention to disclose, IT proficiency moderates the relationship between HISA and intention to disclose. In addition, HISA negatively affects reporting assessment and intention to disclose. This paper aims to fill a research gap in understanding factors affecting insiders' intentions to disclose protected health information. We identify and investigate factors (e.g., collectivism, HISA, reporting assessment, and IT proficiency) that may affect insiders' disclosing intentions. We find that collectivism affects two components of HISA which influence reporting assessment and disclosing intention. We also discover that IT proficiency moderates the relationship between HISA and intention to disclose. Our findings suggest that we need to carefully consider personal factors such as collectivistic nature and IT proficiency in managing insiders' security breaches.

Cell-cell communication is important for cellular differentiation, organ function, and immune responses. In intercellular communication, the extracellular vesicles (EVs) play a significant role in delivering the cargo molecules such as genes, proteins, and enzymes, to regulate and control the ability of the recipient cells. In this study, the observation of intercellular cargo transfer

The ionic conductivity, bend strength, and electrochemical performance in a seawater battery (SWB) of an Na3.1Zr1.55Si2.3P0.7O11 (vA-NASICON) solid electrolyte were compared to those of Na3Zr2Si2PO12 (H-NASICON). vA-NASICON exhibited three times higher total ionic conductivity (8.6 × 10-4 S/cm) than H-NASICON (2.9 × 10-4 S/cm). This is due to the higher bulk ionic conductivity and lower grain boundary resistance of vA-NASICON. The higher bulk conductivity of vA-NASICON is a result of its higher Na content, leading to a larger concentration of charge carriers and/or the formation of a higher conductive rhombohedral phase. The lower grain boundary resistance of vA-NASICON is a result of its larger grain size and reduced ZrO2 content. The bend strength of vA-NASICON (95 MPa) was 30% higher than that of the H-NASICON ceramic. The higher bend strength of vA-NASICON was attributed to its reduced ZrO2 secondary phase (1.1 vol %) compared to that of H-NASICON (2.6 vol %). When the vA-NASICON ceramic was tested in the SWB as a solid electrolyte, an 8.27% improved voltage efficiency and 81% higher power output were demonstrated, compared to those of H-NASICON, as a result of its higher total ionic conductivity and mechanical strength. At the same time, the vA-NASICON membrane revealed comparable cycle life (1000 h) to that of H-NASICON. These results suggest that vA-NASICON can be a better alternative than H-NASICON for use in the SWB.

The purpose of this study is to examine differences in marital and sexual values according to gender, age, and Protestantism contexts using the 2012 and 2018 Korea General Social Surveys. Samples for marital values were from the 2012 survey (N=797 adults aged 20 and over), and those for sexual values were from the 2018 survey (N=550 adults aged 20 and over). There were four domains in marital values (happiness, child, cohabitation, and divorce) and three domains in sexual values (premarital intercourse, extramarital intercourse, and same-sex intercourse). We applied ANCOVA and post hoc analysis to examine the differences in each domain via gender, age, and Protestantism contexts. Results on marital values did not show significant interactions between gender, age group, and Protestantism contexts, while age differences were consistently significant in all domains of marital values. In results about sexual values, there were significant interactions between gender, age, and Protestantism contexts in all domains of sexual values. The findings of this study may promote an understanding of the dynamics and diversity of Korean contexts on marital and sexual values.

Concentric tube robots are catheter-sized continuum robots that show dexterous movement for minimally invasive surgical procedures. However, one of the major challenges to the practical usage of concentric tube robots is their instability, which potentially leads to the risk of tissue rupture. The snapping problem is caused by tubes having a high bending to torsional stiffness ratio (BTSR). Past efforts have shown that anisotropic patterning on tubes can alleviate the snapping problem. This research investigates the design optimization of patterns to minimize BTSR while satisfying stiffness constraints. Using topology optimization methods, rhombus-shaped patterns were identified as the ideal shape for stability. The generated designs were validated through finite element analysis and experimental testing to show the change of BTSR and the elimination of the snapping problem. Extensive parametric study is performed to analysis the sensitivity of the design parameters and provide the design guidelines. While satisfying the constraints, the proposed design method demonstrated 0.28 of BTSR with a rhombus angle of 60 degrees and a volume fraction of 0.55. The optimized design potentially improves the workspace and versatile trajectories of concentric tube manipulators.

Upconverting nanoparticles (UCNPs) have been extensively investigated for nanophotonics and biomedical applications. However, establishing a unified view of their emission characteristics to elucidate the underlying photophysics and expand the application fields of these materials is a great challenge due to their sophisticated internal energy transfer and lack of standardized single-particle spectroscopy (SPS) platform. Here, we present an SPS technique called multiband single-particle irradiance-dependent imaging (multiband SPIDI). We demonstrate that the emission characteristics of Yb