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Single‐walled carbon nanotubes (SWCNTs) have gained significant interest for their potential in biomedicine and nanoelectronics. The functionalization of SWCNTs with single‐stranded DNA (ssDNA) enables the precise control of SWCNT alignment and the development of optical and electronic biosensors. This study addresses the current gaps in the field by employing high‐throughput systematic selection, enriching high‐affinity ssDNA sequences from a vast random library. Specific base compositions and patterns are identified that govern the binding affinity between ssDNA and SWCNTs. Molecular dynamics simulations validate the stability of ssDNA conformations on SWCNTs and reveal the pivotal role of hydrogen bonds in this interaction. Additionally, it is demonstrated that machine learning could accurately distinguish high‐affinity ssDNA sequences, providing an accessible model on a dedicated webpage (http://service.k‐medai.com/ssdna4cnt). These findings open new avenues for high‐affinity ssDNA‐SWCNT constructs for stable and sensitive molecular detection across diverse scientific disciplines. [ABSTRACT FROM AUTHOR]

ABSTRACT The study by Monocello et al. presents findings from a cultural model analysis providing support for culturally bounded understandings of weight and shape and body ideals, and identifying factors that vary across culturally anchored weight categories. In this commentary, we highlight the value of utilizing emic perspectives and employing cultural models in research focused on body image and disordered eating, and the usefulness of these empirical data among Korean men who constitute an underrepresented group in the eating disorders literature. In addition, methodological and contextual aspects that warrant consideration in the interpretation of the results are highlighted. Finally, directions for future research are presented focused on body image and disordered eating among Korean men, as well as leveraging cultural models more broadly in the field. We hope that the study by Monocello and colleagues will stimulate additional research that centers the perspectives of underrepresented groups in ways that elevate and honor their experiences and help to shift the field away from a White‐centered perspective. [ABSTRACT FROM AUTHOR]

An additive, 1,4‐butadiene sulfone (BDS), which generates H2SO3 by in situ thermal retro‐Diels‐Alder decompositions, is used for preparing high β‐phase polyvinylidene fluoride (PVDF) films. Because of preferential multiple non‐covalent interactions of H2SO3 with all‐trans configuration of PVDF, β‐phase PVDF is spontaneously induced without mechanical drawing and/or extensive thermal annealing process. PVDF films cast from PVDF/BDS/water solutions exhibit high β‐phase content (fβ = 95%) when the BDS concentration is only cBDS = 1.0 wt%, which is confirmed by polarized optical microscopy (POM), SEM, Fourier transform infrared spectroscopy (FT‐IR), differential scan calorimetry (DSC), and 2D grazing incidence wide‐angle X‐ray scattering (GIWAXS). Because of the high β‐phase content, PVDF films prepared by using BDS exhibit excellent ferroelectric and piezoelectric properties (Ec = 50 MV/m, Pr = 5 µC/cm2, and d33 = ≈‐25 pm/V). Furthermore, a triboelectric nanogenerator (TENG) developed with high β‐phase PVDF film exhibits enhanced performance as 2.5 times higher than neat PVDF film in output charge density, allowing reliable operation of conventional electronic devices. [ABSTRACT FROM AUTHOR]

Background: Little is known about occupational class differences in pancreatic cancer survival. Methods: Using a population‐based cancer registry in Japan, 3 578 patients with incident pancreatic cancer (1970‐2011) were followed up for 5 years (median follow‐up time 0.42 years). We classified patients into four occupational classes based on their longest‐held jobs: white‐collar (professional and managers), service, blue‐collar, and those not actively employed. Using white‐collar class as the reference group, hazard ratios (HRs) and 95% confidence intervals (CIs) for overall death were estimated by Cox proportional hazard model. Covariates included age, sex, and year of diagnosis. Prognostic variables (pathology, stage, and treatment) and smoking behaviors were additionally adjusted as possible mediating factors. Results: Overall survival was poor in this population (median, 0.50 and 0.33 years in white‐collar and service classes, respectively). Compared with white‐collar patients, survival was significantly poorer across all occupational classes, most pronounced in the service worker group: mortality HRs ranged from 1.11 (95% CI 1.00‐1.24) in blue‐collar workers to 1.24 (95% CI 1.12‐1.37) in service workers. Even after controlling for potential mediating factors, service workers showed worse survival. Conclusion: We documented occupational class disparities in pancreatic cancer survival in Japan. Even in the setting of lethal prognostic cancer with universal health coverage, high‐occupational class groups may enjoy a health advantage. [ABSTRACT FROM AUTHOR]

Abstract: The precisely controllable self‐assembly phenomenon of block copolymers (BCPs) has garnered much attention because it yields well‐defined periodic nanostructures with a periodicity of 5–50 nm. However, from both thermodynamic and kinetic viewpoints, it still remains a challenge to develop a BCP material that can provide sub‐10 nm resolution, high pattern quality, fast pattern formation, and sufficient etch selectivity. To address these challenges, this study reports a BCP system containing a random‐copolymerized block (poly(2‐vinylpyridine‐co‐4‐vinylpyridne)‐b‐poly(dimethylsiloxane) (P(2VP‐co‐4VP)‐b‐PDMS)) that can provide sub‐6 nm resolution, 3σ line edge roughness of 0.89 nm, sub‐1‐min assembly time, and a high etch selectivity over 10. Calculation of the Flory–Huggins interaction parameter (χ) based on Leibler's mean‐field theory and small‐angle X‐ray scattering measurement data confirms the gradual tunability of χ with the controlled addition of 4VP fraction in the P(2VP‐co‐4VP) block. While guaranteeing kinetically fast self‐assembly within one minute using microwave annealing, the best pattern quality resulting from the thermodynamic suppression of line edge fluctuation is achieved with a 4VP weight fraction of 33% in the random‐copolymerized block. This approach enables systematical control of sub‐6 nm scale BCP self‐assembly and will provide a practical patterning solution for diverse nanostructures and devices. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the prevalence and risk factors for disordered weight control behaviors (DWCB) in South Korean adolescents at multiple levels, including individual, family, school, and geographic area. Method: We drew participants from the 11th Korea Youth Risk Behavior Web‐based Survey, conducted in 2015, with 65,529 adolescents (31,687 girls, 33,842 boys) aged 12–18 years. DWCB was defined as engaging in any of the following behaviors for weight control over the past month: fasting, one‐food diet (eating only one food over an extended period of time for weight control), vomiting, and taking laxatives/diuretics/unprescribed diet pills. Sex‐stratified four‐level multilevel logistic models examined potential predictors of DWCB, including age, body‐mass index, puberty, perceived household economic status, parental education, living structure, school type and sex‐composition, percentage of students participating in school nutrition programs, and urbanicity. Results: Overall, 6.2% of Korean adolescents (8.9% of girls, 3.7% of boys) exhibited any DWCB. We found significant between‐school variation among girls and boys and between‐classroom variation among girls. Older age, overweight/obesity, pubertal maturity, high household economic status (vs. mid‐range economic status), and vocational schooling (vs. general) were positively associated with DWCB among girls and boys. Low household economic status (vs. mid‐range economic status), higher parental education, and coeducational schooling (vs. single‐sex) were positively associated with DWCB among girls only. Discussion: The findings suggest that DWCB are prevalent among Korean adolescents across age, sex, and socioeconomic status. Social contextual factors including school and familial environmental factors, as well as individual characteristics, should be considered when developing effective prevention strategies. [ABSTRACT FROM AUTHOR]

The directed self-assembly (DSA) of block copolymers (BCPs) has been suggested as a promising nanofabrication solution. However, further improvements of both the pattern quality and manufacturability remain as critical challenges. Although the use of BCPs with a high Flory-Huggins interaction parameter ( χ) has been suggested as a potential solution, this practical self-assembly route has yet to be developed due to their extremely slow self-assembly kinetics. In this study, it is reported that warm solvent annealing (WSA) in a controlled environment can markedly improve both the self-assembly kinetics and pattern quality. A means of avoiding the undesirable trade-off between the quality and formation throughput of the self-assembled patterns, which is a dilemma which arises when using the conventional solvent vapor treatment, is suggested. As a demonstration, the formation of well-defined 13-nm-wide self-assembled patterns (3σ line edge roughness of ≈2.50 nm) in treatment times of 0.5 min (for 360-nm-wide templates) is shown. Self-consistent field theory (SCFT) simulation results are provided to elucidate the mechanism of the pattern quality improvement realized by WSA. [ABSTRACT FROM AUTHOR]

Highly ordered pattern formation of block copolymers (BCPs) within nanoscale templates is of great interest for generating diverse ordered nanostructures. Here, introduced is a combined methodology of nanotransfer printing (nTP) and BCP self‐assembly to guide the formation of spherical nanodots within a printed crossbar nanotemplate. By successfully accommodating poly(styrene‐b‐dimethylsiloxane) (PS‐b‐PDMS) BCPs in the guiding metallic crossbar nanotemplate (≈30 × 30 nm2), a well‐organized array of single‐domain PDMS spheres (≈10 nm) with a square symmetry is successfully obtained in an extremely short annealing time (<5 s). The self‐consistent field theory simulation results theoretically explain the spontaneous one‐to‐one accommodation of PDMS spheres in the confined area of the crossbar template. This approach can potentially be extended to the many other BCP materials and morphologies to diversify the geometry of self‐assembled BCP and/or transfer‐printed nanopatterns for various types of nanodevice applications. Pattern formation of the complex hybrid structure of dot‐in‐mesh can be achieved by a combined method involving nanotransfer printing and self‐assembly of block copolymer. Here, it is shown how the self‐assembled SiOx nanodots can be located in the confined area of Al nanomesh, showing a spontaneous one‐to‐one accommodation of SiOx nanoparticles within the squared nanospaces. [ABSTRACT FROM AUTHOR]