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Amphiphilic Fluorinated Block Copolymer Additives for Ultrastable Aqueous Zn-Ion Batteries
No full textIn this study, we explored a high-throughput automated chromatography strategy for fast screening high-performance fluorinated block copolymers as electrolyte additives for ultrastable Zn-ion batteries. The proposed polymer, synthesized through controlled reversible addition–fragmentation chain-transfer (RAFT) polymerization, features a hydrophilic oligo(ethylene glycol) methyl ether acrylate (OEGA) block to provide water solubility, and a fluorophilic perfluoropolyether (PFPE) segment as the fluorine source. Our investigations reveal that the balance between OEGA and fluorine plays a key role in modulating interactions between Zn2+ and the fluorinated polymer additives. The degree of polymerization (DP) of OEGA affects both the coordination environment of Zn2+ and water and the exposure of the hydrophobic fluorinated core. Meanwhile, the fluorinated segment facilitates the formation of a protective ZnF2-rich layer, contributing to the stabilization of the solid electrolyte interphase (SEI). Benefiting from this synergistic effect, the polymer additive significantly improves battery performance, achieving stable cycling for 3800 h in symmetric Zn|Zn cells with a Coulombic efficiency (CE) of over 99.6% in Zn|Cu cells. Notably, the Zn|NVO full cell demonstrates excellent capacity retention, maintaining 98.4% of its initial capacity after 5000 cycles at 5 A g–1, with a per-cycle capacity decay as low as 0.00032%. In addition, the Zn|NVO pouch cell delivers stable cycling with a capacity retention of 92% after 700 cycles. This work highlights the important role of composition balance in developing fluorinated polymer additives, puts forward valuable molecular design guidelines for functional additives for practical energy storage applications.No Full Tex
Uncovering bacterial pseudaminylation with pan-specific antibody tools
No full textPseudaminic acids (Pse) are a family of carbohydrates found within bacterial lipopolysaccharides, capsular polysaccharides and glycoproteins that are critical for the virulence of human pathogens. However, a dearth of effective tools for detecting and enriching Pse has restricted study to only the most abundant Pse-containing glycoconjugates. Here we devise a synthesis of α- and β-O-pseudaminylated glycopeptides to generate ‘pan-specific’ monoclonal antibodies (mAbs) that recognize α- and β-configured Pse with diverse N7 acyl groups, as well as its C8 epimer (8ePse), presented within glycans or directly linked to polypeptide backbones. Structural characterization reveals the molecular basis of Pse recognition across a range of diverse chemical contexts. Using these mAbs, we establish a glycoproteomic workflow to map the Pse glycome of Helicobacter pylori, Campylobacter jejuni and Acinetobacter baumannii strains. Finally, we demonstrate that the mAbs recognize diverse capsule types in multidrug-resistant Acinetobacter baumannii and enhance phagocytosis to eliminate infections in mice. (Figure presented.)No Full Tex
Sustainable small-scale fisheries development: Integrating bioeconomic and DPSIR models for policy insights
Get PDFWorldwide, small-scale fisheries face significant challenges due to overfishing, which is more severe in developing countries. This study introduces a novel methodology combining bioeconomic and Driver-Pressure-State-Impact and Response models to assess overfishing using Sri Lanka as a case study. It also provides policy recommendations for sustainable fisheries development. The analysis of 32 years of fish catch and effort data reveals a 130% increase in fishing effort between 1990 and 2021. Factors such as rising fish demand, post-tsunami and post-conflict livelihood recovery aids, and poaching have contributed to this increase, leading to overfishing for more than a decade. The resulting consequences include declining fish catches, incomes, and traditional fishing practices, alongside growing conflicts among fishermen. To address these challenges, the study emphasises the need for fishing effort reductions through targeted strategies. Aligned with Sri Lanka’s policy priorities of employment preservation and sustainable resource management, this study recommends a modest 5% reduction in fishing efforts, incrementally progressing to 25%. These options may include vessel buyback programs and the introduction of fishing-free days, supported by financial incentives. Additional policy recommendations include promoting inland fisheries, combating poaching, and preserving traditional fisheries. Together, these measures aim to balance sustainable resource management with the socioeconomic well-being of fishing communities, offering a comprehensive pathway toward sustainable fisheries development.Full Tex
Assessment of trace elements and fluoride pollution with soil quality evaluation under different land use types in southern hilly region of China
No full textSoil pollution threatens agricultural sustainability and ecosystem health in southern hilly regions of China. To provide methods for targeted soil management, this study conducted an integrated soil quality assessment across three agricultural land use types (orchard soil (OS), paddy soil (PS), and tea garden soil (TS)) in Anhua County, Hunan Province. A total of 93 topsoil samples were collected, and their physicochemical properties, trace elements, and fluoride (F) contents were analyzed. Pollution levels were quantified using the single-factor pollution index (Pᵢ) and Nemerow pollution index (Pₙ). Ecological risk was evaluated via the comprehensive ecological risk index (RI). Soil quality was assessed using a soil quality index (SQI) derived from a minimum data set (MDS), which was screened via principal component analysis (PCA). Results showed significant specific land use differences in soil properties and contaminant concentrations: (1) pH, available potassium(AK), and available phosphorus(AP) varied markedly across OS, PS, and TS; (2) PS had the highest concentrations of Cd, Pb, and F, with these values exceeding the local soil background levels; (3) The comprehensive ecological risk was moderately high overall, following the order PS > TS > OS, and was primarily driven by Cd and Hg; (4) The MDS-SQI assessment revealed soil quality ranked OS (0.60) > PS (0.53) > TS (0.48), with TS was quality mainly constrained by soil acidification and elevated F content. We evaluated soil quality by integrating soil physicochemical properties, trace elements, and F into SQI. This integrated assessment approach not only supports targeted soil management in Anhua County but also provides a reference for soil quality evaluation in other hilly regions of southern China.No Full Tex
The effect of gender and social support on student-athlete and regular student burnout trajectories across lower secondary school
Get PDFSchool burnout symptoms are increasing among adolescents in Nordic countries, especially among female students. In this study, we investigated the trajectories of school burnout symptoms (overall symptoms, exhaustion, cynicism, and inadequacy) across three years of lower secondary education (ages 13–15) among Finnish student-athletes (n = 265; 117 female, 148 male) and regular students (n = 174; 95 female, 79 male). We also examined how these trajectories were associated with gender and social support from the students' teachers, peers, and parents. The participants completed the associated questionnaires three times during lower secondary school. Latent growth models showed that there were no differences in burnout symptoms between student-athletes and regular students at baseline. Female students and female student-athletes reported more burnout symptoms at baseline, and female student-athletes became more exhausted over time. Teacher and peer support were associated with lower rates of increase in burnout symptoms over time. Educational relevance and implications statement: By examining school burnout trajectories and their associations with student-athlete status, gender, and social support from teachers, peers, and parents, we provide new insights into the development of school burnout symptoms in different student groups across lower secondary education (ages 13–15). The findings suggest that being an adolescent female student and female student-athlete may be a risk factor for school burnout. Lower secondary schools should consider this finding and provide additional support for female students and female student-athletes already at the early stages of the school years. Additionally, schools should develop practices to ensure that the combined demands of schoolwork and athletic training do not exceed female student-athletes' coping resources throughout over time. To avert students' burnout in school, continuous attention needs to be paid to teacher and peer relationships.Full Tex
Flexible and Stretchable Silicon Carbide Nanomembranes for Implantable Applications
No full textImplantable devices such as pacemakers, cochlea implants, and deep brain stimulators are vital tools for the treatment of several chronic diseases. While commercial implantable systems are built on rigid substrates, recent efforts focus on transitioning these rigid systems into soft, stretchable forms that can mechanically conform to three-dimensional (3D), soft, and dynamic living tissues. Silicon carbide (SiC) has been explored as a promising material for long-term flexible bioelectronic interfaces. However, developing a highly stretchable and soft SiC electrode system remains a significant challenge. In this study, we utilized a compressive buckling technique and backside photolithography to fabricate a highly deformable and stretchable 3D bioelectronic interface composed of a multiple-nanoscale-thickness SiC electrode array. The 3D SiC platform offers several physical sensing capabilities, including temperature and impedance sensing suitable for invasive procedures and implant devices. Ex vivo heart pacing experiments on rabbit cardiac tissue highlight the potential of 3D, nanothin SiC as a mechanically stretchable and chemically stable electrode platform for delivering stimulation to highly deformable, dynamics organs.No Full Tex
Soft Actor–Critic-Based Anti-Sway Control for Port Crane Systems Based on a Novel Set-Membership Global Estimation Strategy
No full textThis article presents a soft actor–critic (SAC)-based control method for the anti-sway problem of port crane systems under complex working conditions. First, considering the uncertainty of environmental disturbances, a distributed set-membership (SM) estimation strategy with multisensor is proposed to obtain the state information of the crane. Moreover, a fusion method considering kernel density estimation (KDE) and information entropy (IE) is proposed to dynamically assess sensor reliability and obtain the refined global state estimation. Second, an SAC anti-sway control framework with SM global estimation is developed for optimizing control parameters amid system constraints. The control strategy steers the system toward tracking the target state by designing a reward function, achieving optimized control adapted to dynamic disturbances, and improving antisway efficiency. Finally, the effectiveness and superiority of the proposed approach are validated by performance analysis.No Full Tex
iMprovIng the meNtal hEalth of home healTh AiDeS: A study protocol for the MINDSET study
No full textHome health aides and attendants (HHAs) are a fast-growing healthcare workforce who are integral to the rising movement that allows older adults to age in place. However, HHAs themselves are a vulnerable group of caregivers. Mostly middle-aged women of color paid dismally low wages, HHAs' work is physically taxing, emotionally challenging, and socially isolating. Consequently, HHAs have high levels of depressive symptoms and stress. Prior studies suggest that HHAs want to address this, but do not know how and cannot access or afford traditional mental health services. Here we describe the protocol for a pilot randomized control trial (RCT) that aims to improve the mental health of HHAs through peer coaching (PC), an established and effective behavioral health intervention which has never been applied to HHAs or their workplace, the home environment. In collaboration with a labor and management fund of the largest healthcare union in the US (1199SEIU), we will conduct a single-site parallel arm pilot RCT with 100 HHAs to evaluate the feasibility, acceptability, and effectiveness of an adapted Living Healthy Program for HHAs delivered by PCs (intervention arm) vs. a general health promotion program (attention control arm). Primary effectiveness outcome will be a reduction in depressive symptoms; secondary effectiveness outcomes will be a reduction in stress and loneliness. This study offers a novel and potentially scalable way to improve the health of HHAs, an often overlooked, undervalued, but increasingly vital workforce that is needed to care for our rapidly aging population.No Full Tex
Enhancing Police Officers’ Account-Giving in Post-Shooting Interviews
Get PDFBeing interviewed about an officer involved shooting (OIS) can be a traumatic and anxiety-provoking experience for subject officers.
Officers’ accounts of an OIS will be improved by reducing the discomfort experienced and the cognitive load placed on subject officers.
Keeping subject officers informed and interviewer demonstrations of procedural justice likely lead to more open engagement and better-quality accounts.Full Tex
Promoted water dissociation via harnessing Ir oxidation-state boundary for robust hydrogen evolution catalysis
No full textOptimizing the electronic structure of active sites is critical for designing advanced hydrogen evolution reaction (HER) electrocatalysts, yet the precise role of the oxidation state remains debated. Here, we systematically tuned the oxidation state of iridium nanoclusters (∼2 nm) supported on a NiCoFe(OH)x substrate via a controlled anodization strategy. We establish a distinct volcano-type relationship between the Ir oxidation state and HER activity. The optimal catalyst, with a precisely tuned Ir average oxidation state of 1.34, delivers an exceptional HER current density of 507.7 mA cm−2 at a 100 mV overpotential and exhibits outstanding stability for over 250 h in both alkaline and seawater electrolysis. Mechanistic studies using in situ electrochemical impedance spectroscopy reveal that this enhancement originates from accelerated water dissociation and improved interfacial electron transfer. This work underscores that precisely tuning the noble metal oxidation state is a powerful strategy for designing highly active and robust electrocatalysts for energy conversion.No Full Tex