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The growing global energy demand necessitates the development of renewable energy solutions to mitigate greenhouse gas emissions and air pollution. To efficiently utilize renewable yet intermittent energy sources such as solar and wind power, there is a critical need for large-scale energy storage systems (EES) with high electrochemical performance. While lithium-ion batteries (LIBs) have been successfully used for EES, the surging demand and price, coupled with limited supply of crucial metals like lithium and cobalt, raised concerns about future sustainability. In this context, potassium-ion batteries (PIBs) have emerged as promising alternatives to commercial LIBs. Leveraging the low cost of potassium resources, abundant natural reserves, and the similar chemical properties of lithium and potassium, PIBs exhibit excellent potassium ion transport kinetics in electrolytes. This review starts from the fundamental principles and structural regulation of PIBs, offering a comprehensive overview of their current research status. It covers cathode materials, anode materials, electrolytes, binders, and separators, combining insights from full battery performance, degradation mechanisms, in situ/ex situ characterization, and theoretical calculations. We anticipate that this review will inspire greater interest in the development of high-efficiency PIBs and pave the way for their future commercial applications.
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Batteries play a pivotal role in various electrochemical energy storage systems, functioning as essential components to enhance energy utilization efficiency and expedite the realization of energy and environmental sustainability. Zn-based batteries have attracted increasing attention as a promising alternative to lithium-ion batteries owing to their cost effectiveness, enhanced intrinsic safety, and favorable electrochemical performance. In this context, substantial endeavors have been dedicated to crafting and advancing high-performance Zn-based batteries. However, some challenges, including limited discharging capacity, low operating voltage, low energy density, short cycle life, and complicated energy storage mechanism, need to be addressed in order to render large-scale practical applications. In this review, we comprehensively present recent advances in designing high-performance Zn-based batteries and in elucidating energy storage mechanisms. First, various redox mechanisms in Zn-based batteries are systematically summarized, including insertion-type, conversion-type, coordination-type, and catalysis-type mechanisms. Subsequently, the design strategies aiming at enhancing the electrochemical performance of Zn-based batteries are underscored, focusing on several aspects, including output voltage, capacity, energy density, and cycle life. Finally, challenges and future prospects of Zn-based batteries are discussed.
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The integration of chirality, specifically through the chirality-induced spin selectivity (CISS) effect, into electrocatalytic processes represents a pioneering approach for enhancing the efficiency of energy conversion and storage systems. This review delves into the burgeoning field of chiral electrocatalysis, elucidating the fundamental principles, historical development, theoretical underpinnings, and practical applications of the CISS effect across a spectrum of electrocatalytic reactions, including the oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER). We explore the methodological advancements in inducing the CISS effect through structural and surface engineering and discuss various techniques for its measurement, from magnetic conductive atomic force microscopy (mc-AFM) to hydrogen peroxide titration. Furthermore, this review highlights the transformative potential of the CISS effect in addressing the key challenges of the NRR and CO2RR processes and in mitigating singlet oxygen formation in metal-air batteries, thereby improving their performance and durability. Through this comprehensive overview, we aim to underscore the significant role of incorporating chirality and spin polarization in advancing electrocatalytic technologies for sustainable energy applications.
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In the presence of water, the electrically conductive metal-organic framework (MOF) Cu3HHTT2 (H6HHTT = 2,3,7,8,12,13-hexahydroxy-4b1,5,10,15-tetraazanaphtho[1,2,3-gh]tetraphene) provides a conduit for proton transport, thereby becoming a dual ionic-electronic conductor. Owing to its dual conducting nature and its high density of imine and open metal sites, the MOF operates as a particularly sensitive chemiresistor, whose sensing mechanism changes with relative humidity. Thus, the interaction of NH3 gas with the MOF under low humidity promotes proton transport, which translates to high sensitivity for ammonia detection. Conversely, NO2 gas hinders proton conductivity, even under high relative humidity conditions, leading to large resistance variations in the humid regime. This dual ionic-electronic conduction-based gas sensor provides superior sensitivity compared to other conventional chemiresistors under similar conditions and highlights its potential as a platform for room-temperature gas sensors.
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Single-atom catalysts (SACs) hold immense promise in facilitating the rational use of metal resources and achieving atomic economy due to their exceptional atom-utilization efficiency and distinct characteristics. Despite the growing interest in SACs, only limited reviews have holistically summarized their advancements centering on performance metrics. In this review, first, a thorough overview on the research progress in SACs is presented from a performance perspective and the strategies, advancements, and intriguing approaches employed to enhance the critical attributes in SACs are discussed. Subsequently, a comprehensive summary and critical analysis of the electrochemical applications of SACs are provided, with a particular focus on their efficacy in the oxygen reduction reaction , oxygen evolution reaction, hydrogen evolution reaction , CO2 reduction reaction, and N2 reduction reaction . Finally, the outline future research directions on SACs by concentrating on performance-driven investigation, where potential areas for improvement are identified and promising avenues for further study are highlighted, addressing challenges to unlock the full potential of SACs as high-performance catalysts.
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INTRODUCTIONS: An increasing number of countries are adopting the tobacco endgame goal. High levels of public support can accelerate momentum towards implementing tobacco endgame policies. We aimed to conduct a systematic review of public support for tobacco endgame policies and to examine the geographical distribution of studies, support among key populations (adolescents and young adults, people who smoke), and the association between survey design and support. METHODS: We searched Embase, PubMed, Scopus, Web of Science, and Google Scholar for studies published from 2013 onwards. Google was used to search the grey literature. The reference lists of included articles were hand-searched. Studies were included if they reported the proportions of people supporting one or more endgame policies. Risk of bias was assessed using the JBI checklist for prevalence studies. RESULTS: Forty-seven articles were included. Aotearoa/New Zealand and the United States were the countries with the most studies (n=11, respectively). Three-level meta-analyses showed the highest support for mandating a very low nicotine content in tobacco products (76%, 95% CI 61-87%). Meta-regressions were performed to assess the associations of population subgroup and survey design with support levels. The level of support was lower among people who smoke compared to the general population (ß range: -1.59 to -0.51). Support for some policies was lower when neutral or don't know response options were included. CONCLUSIONS: Public support for most tobacco endgame policies was high. IMPLICATIONS: Assessing public support can assist with progressing tobacco endgame policies. Policies that are widely supported by the public may be more politically feasible to implement. Qualitative studies and trial studies can further inform communication and implementation strategies for tobacco endgame policies.
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Environmentally friendly crosslinked polymer networks feature degradable covalent or non-covalent bonds, with many of them manifesting dynamic characteristics. These attributes enable convenient degradation, facile reprocessibility, and self-healing capabilities. However, the inherent instability of these crosslinking bonds often compromises the mechanical properties of polymer networks, limiting their practical applications. In this context, environmentally friendly dual-crosslinking polymer networks (denoted EF-DCPNs) have emerged as promising alternatives to address this challenge. These materials effectively balance the need for high mechanical properties with the ability to degrade, recycle, and/or self-heal. Despite their promising potential, investigations into EF-DCPNs remain in their nascent stages, and several gaps and limitations persist. This Review provides a comprehensive overview of the synthesis, properties, and applications of recent progress in EF-DCPNs. Firstly, synthetic routes to a rich variety of EF-DCPNs possessing two distinct types of dynamic bonds (i.e., imine, disulfide, ester, hydrogen bond, coordination bond, and other bonds) are introduced. Subsequently, complex structure- and dynamic nature-dependent mechanical, thermal, and electrical properties of EF-DCPNs are discussed, followed by their exemplary applications in electronics and biotechnology. Finally, future research directions in this rapidly evolving field are outlined.
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BACKGROUND AND OBJECTIVES: Walking enhances the health, quality of life, and independence of older adults. However, a global decline in urban walking necessitates a reevaluation of segmented, quantitative approaches to policies and theoretical frameworks in geriatric medicine for promoting walking among older adults. This study conceptualized the perceptions, experiences, and behaviors regarding walking, from a health promotion perspective, among older urban adults. RESEARCH DESIGN AND METHODS: Pedestrian-friendly communities were explored for older adults in Seoul, South Korea, using a grounded theory. Thirty-eight older adults actively engaged in walking were recruited between July and December 2020. A qualitative multi-method approach was used, and the collected data were analyzed using open, axial, and selective coding, with axial coding integrating textual and spatiobehavioral information. RESULTS: The open-coding process yielded 92 concepts, 47 subcategories, and 19 categories. Using axial and selective coding principles, a conceptual framework was developed to explain how walking shaped the daily lives of older urban adults and provided multidimensional health benefits. Walking perception attributes were characterized by "embodied subjectivity as a healthy older adult," "autonomy of movement," and "walking as a way to enrich or sustain life." Active walking facilitated interactions between older adults and their neighborhood environment within the context of compact and accessible urban living. DISCUSSION AND IMPLICATIONS: A healthy and age-friendly community encourages interactions between older adults and their neighborhood environment by providing opportunities for daily walking for several purposes, such as providing a sense of autonomy, increasing health-promoting behaviors, and creating a sense of community.
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INTRODUCTION: The number of single-person households is increasing globally-including in South Korea, where they account for over 30% of all households. Young single-person households in South Korea face health problems and housing challenges. Both the perceived and objective aspects of the neighbourhood environment, as a community asset, play a significant role in sustaining a healthy lifestyle. This study aims to explore and describe the meaning, roles and spatiotemporal characteristics of neighbourhood environments for a healthy lifestyle in young single-person households experiencing housing poverty in Seoul, South Korea. METHODS AND ANALYSIS: This ongoing study uses an extended qualitative geographic information systems approach to explore a district in the city of Seoul that has the highest population density of young single-person households experiencing housing poverty. The study sample comprises young single-person households aged 19-39 years who are experiencing housing poverty in the study area, with an expected saturation point of approximately 55 participants. We employ online and offline recruitment strategies to ensure the inclusion of diverse perspectives and a multimethod approach that combines descriptive and spatiotemporal data collection techniques (eg, individual in-depth interviews, field observations and mobile global positioning system tracking). The data analysis encompasses thematic and content analyses to understand the neighbourhood environment's perceived attributes and the spatiotemporal characteristics of healthy lifestyles. In the integrated analysis, we plan to combine the qualitative findings with living space and daily-life patterns using qualitative software and a hybrid relational database. ETHICS AND DISSEMINATION: The Institutional Review Board of Seoul National University approved the research protocol on 18 May 2021. The findings will be shared at international conferences and published in academic journals. Additionally, an online seminar will be conducted to share the results with policy-makers, researchers, community organisations and health workers working with young single-person households experiencing housing poverty.
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Habitação , Pobreza , Humanos , Seul , República da Coreia , Estilo de Vida Saudável , Características da VizinhançaRESUMO
INTRODUCTION: Amid the growing global concern about obesity, young adults in South Korea are particularly affected, with 30.8% of people aged 19-34 classified as obese. Given the urban-centric lifestyle of Korean youth, understanding the relationship between daily life activities and the urban environment holds great promise for effective interventions. This study aims to explore the daily life activities of young adults with obesity in Seoul, a city known for its highly accessible and compact environment. The research questions explore the interaction between daily life activities and the neighbourhood environment and consider weight management in an urban context. METHODS AND ANALYSIS: This study uses an extended qualitative geographic information system approach to explore a district in Seoul with a highly accessible and compact urban environment. The sample comprises young adults with obesity (aged 19-34) residing in the study area, with recruitment targeting up to 51 participants for data saturation. A qualitative, multimethod approach combines descriptive and spatiotemporal data collection. Descriptive data are being collected, including in-depth interviews and photographs of daily food consumption. Spatial data collection involves field observations, cognitive mapping and mobile Global Positioning System tracking. Temporal data is gathered through participants drawing round timetables, detailing their daily schedules. Data analysis will entail thematic analysis of the interview data and content analysis of the spatiotemporal data. For the integrated analysis, pattern finding will be used to synthesise the data. ETHICS AND DISSEMINATION: This study was approved by the institutional review board of Seoul National University on 11 July 2022. Data collection and curation are currently underway, and the results of the analysis will be shared with the scientific community at international conferences and peer-reviewed journals. We are planning an open seminar to share our research findings with relevant policy-makers, community organisations and health professionals.
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Obesidade , Adolescente , Humanos , Adulto Jovem , Seul , República da Coreia/epidemiologia , Obesidade/epidemiologia , CidadesRESUMO
The current study aims to fill the existing research gaps by investigating the role of teacher care in protecting African American adolescents in under-resourced neighborhoods from negative outcomes of adverse life events. The study included 638 adolescents from four under-resourced neighborhoods in Chicago's Southside who were assessed to determine the moderating role of caring teachers on the relationship between adverse adolescent experiences and risky sexual behaviors, substance use, bullying perpetration, and violent behaviors. Caring teachers had a significant moderating effect on the association between adverse experiences and both bullying perpetration and violent behaviors. Adolescents who perceived their teachers as caring showed lower tendencies towards bullying and violence, even if they had adverse experiences. These results highlight the crucial role of teacher care in supporting African American adolescents from under-resourced neighborhoods who have experienced adverse life events. It emphasizes educators' role in shaping our youth's future, especially those facing adversity and at a crossroads in their lives.
Despite adverse life events, adolescents who perceived their teachers as caring were less at risk of engaging in bullying and violence. Caring teachers are especially important for African American adolescents in under-resourced neighborhoods.
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INTRODUCTION: Using the 2017 National Crime Victimization Survey dataset, this study examined the association between the types of school security measures and students' bullying victimization and perceived school safety. METHOD: Using logistic regression and ordinary least square regression analyses, the study addressed whether these associations vary by sex and race/ethnicity, as most research has treated sex and race/ethnicity as covariates. RESULTS: The study found that none of the security measures were associated with bullying victimization among the total sample. However, there were sex and racial differences in the association between security measures and bullying victimization. There were also sex and racial/ethnic variations in the association between security measures and perceived school safety. DISCUSSION: Scholars, health care practitioners, and policymakers must reflect and reconsider whether increasing school security and control would contribute to the safety and well-being of racial/ethnic minority students in school.
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Bullying , Vítimas de Crime , Criança , Humanos , Etnicidade , Grupos Minoritários , Bullying/prevenção & controle , Instituições Acadêmicas , Medidas de SegurançaRESUMO
Metal-organic frameworks (MOFs) are promising materials for gas sensing but are often limited to single-use detection. A hybridization strategy is demonstrated synergistically deploying conductive MOFs (cMOFs) and conductive polymers (cPs) as two complementary mixed ionic-electronic conductors in high-performing stand-alone chemiresistors. This work presents significant improvement in i) sensor recovery kinetics, ii) cycling stability, and iii) dynamic range at room temperature. The effect of hybridization across well-studied cMOFs is demonstrated based on 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) and 2,3,6,7,10,11-hexaiminotriphenylene (HITP) ligands with varied metal nodes (Co, Cu, Ni). A comprehensive mechanistic study is conducted to relate energy band alignments at the heterojunctions between the MOFs and the polymer with sensing thermodynamics and binding kinetics. The findings reveal that hole enrichment of the cMOF component upon hybridization leads to selective enhancement in desorption kinetics, enabling significantly improved sensor recovery at room temperature, and thus long-term response retention. This mechanism is further supported by density functional theory calculations on sorbate-analyte interactions. It is also found that alloying cPs and cMOFs enables facile thin film co-processing and device integration, potentially unlocking the use of these hybrid conductors in diverse electronic applications.
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This study proposes the use of physical unclonable functions employing circularly polarized light emission (CPLE) from nematic liquid crystal (NLC) ordering directed by helical nanofilaments in a mixed system composed of a calamitic NLC mixture and a bent-core molecule. To achieve this, an intrinsically nonemissive NLC is blended with a high concentration of a luminescent rod-like dye, which is miscible up to 10 wt % in the calamitic NLC without a significant decrease in the degree of alignment. The luminescence dissymmetry factor of CPLEs in the mixed system strongly depends on the degree of alignment of the dye-doped NLCs. Furthermore, the mixed system prepared in this study exhibits two randomly generated chiral domains with CPLEs of opposite signs. These chiral domains are characterized not only by their CPLE performances but also by their ability to generate random patterns up to several millimeters, making them promising candidates for high-performance secure authentication applications.
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The chemical stability and energy density of redox couples are crucial factors in enhancing the durability and cost competitiveness of aqueous flow batteries. This study proposed integrating functional groups to viologen anolyte to increase its solubility and, consequently, energy density and stability for prolonged performance. Specifically, sulfonate and ester groups were selectively incorporated at the nitrogen sites of viologen to enhance solubility, leveraging their asymmetry and double hydrophilicity. Furthermore, an alpha-methyl group was introduced between the bipyridine and ester groups to enhance the chemical stability by preventing stacking and dimerization that can lead to irreversible degradation. The modified viologen demonstrated a remarkable solubility of 3.0 M in deionized water, corresponding to a volumetric capacity of 80.404 Ah L-1. Additionally, the designed viologen exhibits outstanding retention of 92.4% after 200 cycles with a minimal capacity fading rate of 0.055% per cycle in a 0.1 M flow cell test.
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BACKGROUND: Tumor-derived exosomes are critical elements of the cell-cell communication response to various stimuli. This study aims to reveal that the histone deacetylase 5 (HDAC5) and p53 interaction upon radiation in hepatocellular carcinoma intricately regulates the secretion and composition of exosomes. METHODS: We observed that HDAC5 and p53 expression were significantly increased by 2 Gy and 4 Gy radiation exposure in HCC. Normal- and radiation-derived exosomes released by HepG2 were purified to investigate the exosomal components. RESULTS: We found that in the radiation-derived exosome, exosomal Maspin was notably increased. Maspin is known as an anti-angiogenic gene. The expression of Maspin was regulated at the cellular level by HDAC5, and it was elaborately regulated and released in the exosome. Radiation-derived exosome treatment caused significant inhibition of angiogenesis in HUVECs and mouse aortic tissues. Meanwhile, we confirmed that miR-151a-3p was significantly reduced in the radiation-derived exosome through exosomal miRNA sequencing, and three HCC-specific exosomal miRNAs were also decreased. In particular, miR-151a-3p induced an anti-apoptotic response by inhibiting p53, and it was shown to induce EMT and promote tumor growth by regulating p53-related tumor progression genes. In the HCC xenograft model, radiation-induced exosome injection significantly reduced angiogenesis and tumor size. CONCLUSIONS: Our present findings demonstrated HDAC5 is a vital gene of the p53-mediated release of exosomes resulting in tumor suppression through anti-cancer exosomal components in response to radiation. Finally, we highlight the important role of exosomal Maspin and mi-151a-3p as a biomarker in enhancing radiation treatment sensitivity. Therapeutic potential of HDAC5 through p53-mediated exosome modulation in radiation treatment of hepatocellular carcinoma.