Tailoring atomic chemistry to refine reaction pathway for the most enhancement by magnetization in water oxidation.

Water oxidation on magnetic catalysts has generated significant interest due to the spin-polarization effect. Recent studies have revealed that the disappearance of magnetic domain wall upon magnetization is responsible for the observed oxygen evolution reaction (OER) enhancement. However, an atomic picture of the reaction pathway remains unclear, i.e., which reaction pathway benefits most from spin-polarization, the adsorbent evolution mechanism, the intermolecular mechanism (I2M), the lattice oxygen-mediated one, or more? Here, using three model catalysts with distinguished atomic chemistries of active sites, we are able to reveal the atomic-level mechanism. We found that spin-polarized OER mainly occurs at interconnected active sites, which favors direct coupling of neighboring ligand oxygens (I2M). Furthermore, our study reveals the crucial role of lattice oxygen participation in spin-polarized OER, significantly facilitating the coupling kinetics of neighboring oxygen radicals at active sites.

Breaking the cycle: Reforming pesticide regulation to protect pollinators.

Over decades, pesticide regulations have cycled between approval and implementation, followed by the discovery of negative effects on nontarget organisms that result in new regulations, pesticides, and harmful effects. This relentless pattern undermines the capacity to protect the environment from pesticide hazards and frustrates end users that need pest management tools. Wild pollinating insects are in decline, and managed pollinators such as honey bees are experiencing excessive losses, which threatens sustainable food security and ecosystem function. An increasing number of studies demonstrate the negative effects of field-realistic exposure to pesticides on pollinator health and fitness, which contribute to pollinator declines. Current pesticide approval processes, although they are superior to past practices, clearly continue to fail to protect pollinator health. In the present article, we provide a conceptual framework to reform cyclical pesticide approval processes and better protect pollinators.

Groundwater remediation using Magnesium-Aluminum alloys and in situ layered doubled hydroxides.

In situ remediation of groundwater by zerovalent iron (ZVI)-based technology faces the problems of rapid passivation, fast agglomeration, limited range of pollutants and secondary contamination. Here a new concept of Magnesium-Aluminum (Mg-Al) alloys and in situ layered double hydroxides on is proposed for the degradation and removal of a wide variety of inorganic and organic pollutants from groundwater. The Mg-Al alloy provides the electrons for the chemical reduction and/or the degradation of pollutants while released Mg2+, Al3+ and OH- ions react to generate in situ LDH precipitates, incorporating other divalent and trivalent metals and oxyanions pollutants and further adsorbing the micropollutants. The Mg-Al alloy outperforms ZVI for treating acidic, synthetic groundwater samples contaminated by complex chemical mixtures of heavy metals (Cd2+, Cr6+, Cu2+, Ni2+ and Zn2+), nitrate, AsO33-, methyl blue, trichloroacetic acid and glyphosate. Specifically, the Mg-Al alloy achieves removal efficiency ≥99.7% for these multiple pollutants at concentrations ranging between 10 and 50 mg L-1 without producing any secondary contaminants. In contrast, ZVI removal efficiency did not exceed 90% and secondary contamination up to 220 mg L-1 Fe was observed. Overall, this study provides a new alternative approach to develop efficient, cost-effective and green remediation for water and groundwater.

Suicidal behaviors in the entertainment industry: a preliminary exploration of the interplay between work scheduling, social support, and wellbeing in Australia.

OBJECTIVE: Workers of the Australian entertainment industry exhibit disproportionately high rates of impaired psychological wellbeing and suicidal behaviors, with such rates being exacerbated by the negative impact of working long and odd hours (Work Scheduling Impact; WSI). Nonetheless, stable and secure social support networks may buffer the risks associated with such systemic difficulties. METHODS: The responses of 1302 Australian entertainment industry workers (50.3% females, Mage 38.39 years) on the Multidimensional Scale of Perceived Social Support, the Short Form Health Survey, WSI, and suicidal behaviors questions were examined via moderation analyses. RESULTS: Higher social support and lower WSI appeared to reduce the suicidal ideation of those experiencing poorer mental health, while lower WSI further enhanced social support's positive effect. CONCLUSIONS: Findings highlight the likely detrimental effect of WSI regarding the suicidal ideation reported by vulnerable Australian entertainment industry workers and stress the importance of the social support they experience. PUBLIC HEALTH IMPLICATIONS: Interventions attempting to increase social support could improve inherent conditions associated with the Australian entertainment industry. Similarly, the negative effect of working long and odd hours on workers' mental health and suicidal behaviors indicates the need to regulate the industry appropriately.

Disability organizations as empowering settings: Challenging stigmatization, promoting emancipation.

This study investigated how a local disability organization in Yogyakarta Province, Indonesia, has functioned as an empowering setting for its members. This article discusses, in particular, the context specific features that have enabled members of this organization to resist the pervasive stigmatization commonly imposed upon people with disabilities. The research data was collected through interviews with 18 members of the organization and analyzed using the method of constructivist grounded theory. The findings suggest that this organization exists as an empowering setting because it functions as a mindset changer, an alternative resource center, and fosters supportive and courageous allies. Through this empowerment, members can challenge the normalized stigmatization and promote more emancipatory identities, particularly in a rural context where some socio-cultural aspects may further complicate the disadvantages of people with disabilities. Implications for future research and disability interventions are discussed.

Field cross-fostering and in vitro rearing demonstrate negative effects of both larval and adult exposure to a widely used fungicide in honey bees (Apis mellifera).

Pollinators and other insects are experiencing an ongoing worldwide decline. While various environmental stressors have been implicated, including pesticide exposure, the causes of these declines are complex and highly debated. Fungicides may constitute a particularly prevalent threat to pollinator health due to their application on many crops during bloom, and because pollinators such as bees may consume fungicide-tainted pollen or nectar. In a previous study, consumption of pollen containing the fungicide Pristine® at field-relevant concentrations by honey bee colonies increased pollen foraging, caused earlier foraging, lowered worker survival, and reduced colony population size. Because most pollen is consumed by young adults, we hypothesized that Pristine® (25.2% boscalid, 12.8% pyraclostrobin) in pollen exerts its negative effects on honey bee colonies primarily on the adult stage. To rigorously test this hypothesis, we used a cross-fostering experimental design, with bees reared in colonies provided Pristine® incorporated into pollen patties at a supra-field concentration (230 mg/kg), only in the larvae, only in the adult, or both stages. In contrast to our predictions, exposure to Pristine® in either the larval or adult stage reduced survival relative to control bees not exposed to Pristine®, and exposure to the fungicide at both larval and adult stages further reduced survival. Adult exposure caused precocious foraging, while larval exposure increased the tendency to forage for pollen. These results demonstrate that pollen containing Pristine® can induce significant negative effects on both larvae and adults in a hive, though the magnitude of such effects may be smaller at field-realistic doses. To further test the potential negative effects of direct consumption of Pristine® on larvae, we reared them in vitro on food containing Pristine® at a range of concentrations. Consumption of Pristine® reduced survival rates of larvae at all concentrations tested. Larval and adult weights were only reduced at a supra-field concentration. We conclude that consumption of pollen containing Pristine® by field honey bee colonies likely exerts impacts on colony population size and foraging behavior by affecting both larvae and adults.

The active ingredients of a mitotoxic fungicide negatively affect pollen consumption and worker survival in laboratory-reared honey bees (Apis mellifera).

Recent observations of many sublethal effects of pesticides on pollinators have raised questions about whether standard short-term laboratory tests of pesticide effects on survival are sufficient for pollinator protection. The fungicide Pristine® and its active ingredients (25.2% boscalid, 12.8% pyraclostrobin) have been reported to have low acute toxicity to caged honey bee workers, but many sublethal effects at field-relevant doses have been reported and Pristine® was recently found to increase worker pollen consumption, reduce worker longevity and colony populations at field relevant concentrations (Fisher et al. 2021). To directly compare these whole-colony field results to more standard laboratory toxicology tests, the effects of Pristine®, at a range of field-relevant concentrations, were assessed on the survival and pollen consumption of honey bee workers 0-14 days of age. Also, to separate the effects of the inert and two active ingredients, bees were fed pollen containing boscalid, pyraclostrobin, or pyraclostrobin plus boscalid, at concentrations matching those in the Pristine® treatments. Pyraclostrobin significantly reduced pollen consumption across the duration of the experiment, and dose-dependently reduced pollen consumption on days 12-14. Pristine® and boscalid significantly reduced pollen feeding rate on days 12-14. Boscalid reduced survival in a dose-dependent manner. Consumption of Pristine® or pyraclostrobin plus boscalid did not affect survival, providing evidence against strong negative effects of the inert ingredients in Pristine® and against negative synergistic effects of boscalid and pyraclostrobin. The stronger toxic effects of Pristine® observed in field colonies compared to this laboratory test, and the opposite responses of pollen consumption in the laboratory and field to Pristine®, show that standard laboratory toxicology tests can fail to predict responses of pollinators to pesticides and to provide protection.

Anodic Oxidation Enabled Cation Leaching for Promoting Surface Reconstruction in Water Oxidation.

A rational design for oxygen evolution reaction (OER) catalysts is pivotal to the overall efficiency of water electrolysis. Much work has been devoted to understanding cation leaching and surface reconstruction of very active electrocatalysts, but little on intentionally promoting the surface in a controlled fashion. We now report controllable anodic leaching of Cr in CoCr2 O4 by activating the pristine material at high potential, which enables the transformation of inactive spinel CoCr2 O4 into a highly active catalyst. The depletion of Cr and consumption of lattice oxygen facilitate surface defects and oxygen vacancies, exposing Co species to reconstruct into active Co oxyhydroxides differ from CoOOH. A novel mechanism with the evolution of tetrahedrally coordinated surface cation into octahedral configuration via non-concerted proton-electron transfer is proposed. This work shows the importance of controlled anodic potential in modifying the surface chemistry of electrocatalysts.

Surface Composition Dependent Ligand Effect in Tuning the Activity of Nickel-Copper Bimetallic Electrocatalysts toward Hydrogen Evolution in Alkaline.

Exploring efficient and low-cost electrocatalysts for hydrogen evolution reaction (HER) in alkaline media is critical for developing anion exchange membrane electrolyzers. The key to a rational catalyst design is understanding the descriptors that govern the alkaline HER activity. Unfortunately, the principles that govern the alkaline HER performance remain unclear and are still under debate. By studying the alkaline HER at a series of NiCu bimetallic surfaces, where the electronic structure is modulated by the ligand effect, we demonstrate that alkaline HER activity can be correlated with either the calculated or the experimental-measured d band center (an indicator of hydrogen binding energy) via a volcano-type relationship. Such correlation indicates the descriptor role of the d band center, and this hypothesis is further supported by the evidence that combining Ni and Cu produces a variety of adsorption sites, which possess near-optimal hydrogen binding energy. Our finding broadens the applicability of d band theory to activity prediction of metal electrocatalysts and may offer an insightful understanding of alkaline HER mechanism.

Electrochemical Oxidation of Nitrogen towards Direct Nitrate Production on Spinel Oxides.

Nitrates are widely used as fertilizer and oxidizing agents. Commercial nitrate production from nitrogen involves high-temperature-high-pressure multi-step processes. Therefore, an alternative nitrate production method under ambient environment is of importance. Herein, an electrochemical nitrogen oxidation reaction (NOR) approach is developed to produce nitrate catalyzed by ZnFex Co2-x O4 spinel oxides. Theoretical and experimental results show Fe aids the formation of the first N-O bond on the *N site, while high oxidation state Co assists in stabilizing the absorbed OH- for the generation of the second and third N-O bonds. Owing to the concerted catalysis, the ZnFe0.4 Co1.6 O4 oxide demonstrates the highest nitrate production rate of 130±12 µmol h-1 gMO -1 at an applied potential of 1.6 V versus the reversible hydrogen electrode (RHE).

A Planar, Conjugated N4 -Macrocyclic Cobalt Complex for Heterogeneous Electrocatalytic CO2 Reduction with High Activity.

Metal complexes have been widely investigated as promising electrocatalysts for CO2 reduction. Most of the current research efforts focus mainly on ligands based on pyrrole subunits, and the reported activities are still far from satisfactory. A novel planar and conjugated N4 -macrocyclic cobalt complex (Co(II)CPY) derived from phenanthroline subunits is prepared herein, and it delivers high activity for heterogeneous CO2 electrocatalysis to CO in aqueous media, and outperforms most of the metal complexes reported so far. At a molar loading of 5.93×10-8  mol cm-2 , it exhibits a Faradaic efficiency of 96 % and a turnover frequency of 9.59 s-1 towards CO at -0.70 V vs. RHE. The unraveling of electronic structural features suggests that a synergistic effect between the ligand and cobalt in Co(II)CPY plays a critical role in boosting its activity. As a result, the free energy difference for the formation of *COOH is lower than that with cobalt porphyrin, thus leading to enhanced CO production.

Graphene Oxide Nanoplatelets Potentiate Anticancer Effect of Cisplatin in Human Lung Cancer Cells.

Graphene oxide (GO) has been widely explored by many in drug delivery strategies and toxicity assays. The toxicity of graphene oxide depends on the size of the sheets. Smaller sheets show lower toxicity, a quality which is essential for utilization in biomedical applications. However, despite vast research on GO, anticancer properties and drug carrier capabilities of graphene oxide nanoplatelets have yet to be fully explored. Herein, we have uniquely prepared graphene oxide nanoplatelets (GONPs) from well-defined stacked graphite nanofibers (SGNF) with a base of 50 × 50 nm2 for toxicity and drug potentiation studies when coadministered with the chemotherapeutic drug cisplatin (CP) in human lung cancer cells, A549 cells. Results obtained from our studies have found that not only were GONPs able to act as drug carriers, but they can also significantly potentiate anticancer effect of CP in A549 cells.

Cytotoxicity of Exfoliated Layered Vanadium Dichalcogenides.

Transition-metal Group 5 vanadium dichalcogenides have shown promising properties for many applications, such as batteries, capacitors, electrocatalysts for hydrogen production and many more. However, their toxicological effects have not yet been well understood. Here, we studied the cytotoxicity of exfoliated VS2 , VSe2 and VTe2 by incubating various concentrations of the materials with human lung carcinoma (A549) cells for 24 h and measuring the remaining cell viabilities after the treatment. We found that these vanadium dichalcogenides are relatively more toxic compared to Group 6 transition-metal dichalcogenides (TMDs), namely MoS2 , WS2 and WSe2 . This study is important for a better understanding of the toxicity of TMDs in preparation for their actual commercialisation in the future.

Fourier transform large amplitude alternating current voltammetry investigations of the split wave phenomenon in electrocatalytic mechanisms.

Fourier transform large amplitude alternating current voltammetry (FTACV) studies are reported on an electrocatalytic (EC') mechanistic system which exhibits split wave behavior on both macro- and micro-size working electrodes. The electrochemical characteristics of the EC' mechanism were analysed using the fundamental to fourth harmonic components deduced by the Fourier transform algorithm. The effects of the sinusoidal frequencies of the applied potential, electrode geometry and substrate concentrations are investigated. The split wave phenomenon was observed and explored particularly.

Phase diagram and segregation of Ag-Co nanoalloys: insights from theory and simulation.

Understanding the phase diagram is the first step to identifying the structure-performance relationship of a material at the nanoscale. In this work, a modified nanothermodynamical model has been developed to predict the phase diagrams of Ag-Co nanoalloys with the size of 1 âˆ¼ 100 nm, which also overcomes the difference in the predicted results between theory and simulation for the first time. Based on this modified model, the phase diagrams of Ag-Co nanoalloys with various polyhedral morphologies (tetrahedron, cube, octahedron, decahedron, dodecahedron, rhombic dodecahedron, truncated octahedron, cuboctahedron, and icosahedron) have been predicted, showing good agreement with molecular dynamics simulations at the nanoscale of 1 âˆ¼ 4 nm. In addition, the surface segregation of Ag-Co nanoalloys has been predicted with a Co-rich core/Ag-rich surface, which is also consistent with the simulation results. Our results highlight a useful roadmap for bridging the difference between theory and simulation in the prediction of the phase diagram at the nanoscale, which will help both theorists and experimentalists.

PdCu alloy nanoparticle-decorated copper nanotubes as enhanced electrocatalysts: DFT prediction validated by experiment.

In order to combine the advantages of both 0D and 1D nanostructured materials into a single catalyst, density functional theory (DFT) calculations have been used to study the PdCu alloy NP-decorated Cu nanotubes (PdCu@CuNTs). These present a significant improvement of the electrocatalytic activity of formic acid oxidation (FAO). Motivated by our theoretical work, we adopted the seed-mediated growth method to successfully synthesize the nanostructured PdCu@CuNTs. The new catalysts triple the catalytic activity for FAO, compared with commercial Pd/C. In summary, our work provides a new strategy for the DFT prediction and experimental synthesis of novel metal NP-decorated 1D nanostructures as electrocatalysts for fuel cells.

Surface Segregation in Bimetallic Nanoparticles: A Critical Issue in Electrocatalyst Engineering.

Bimetallic nanoparticles are a class of important electrocatalyst. They exhibit a synergistic effect that critically depends on the surface composition, which determines the surface properties and the adsorption/desorption behavior of the reactants and intermediates during catalysis. The surface composition can be varied, as nanoparticles are exposed to certain environments through surface segregation. Thermodynamically, this is caused by a difference in surface energy between the two metals. It may lead to the enrichment of one metal on the surface and the other in the core. The external conditions that influence the surface energy may lead to the variation of the thermodynamic steady state of the particle surface and, thus, offer a chance to vary the surface composition. In this review, the most recent and important progress in surface segregation of bimetallic nanoparticles and its impact in electrocatalysis are introduced. Typical segregation inducements and surface characterization techniques are discussed in detail. It is concluded that surface segregation is a critical issue when designing bimetallic catalysts. It is necessary to explore methods to control it and utilize it as a way towards producing robust, bimetallic electrocatalysts.

A Flexible Electrode Based on Iron Phosphide Nanotubes for Overall Water Splitting.

The design of cheap and efficient water splitting systems for sustainable hydrogen production has attracted increasing attention. A flexible electrode, based on carbon cloth substrate and iron phosphide nanotubes coated with an iron oxide/phosphate layer, is shown to catalyze overall water splitting. The as-prepared flexible electrode demonstrates remarkable electrocatalytic activity for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) at modest overpotentials. The surface iron oxide/phosphate, which is formed in situ, is proposed to improve the HER activity by facilitating the water-dissociation step and serves directly as the catalytically-active component for the OER process.

The Cytotoxicity of Layered Black Phosphorus.

Black phosphorus (BP), the latest addition to the family of 2D layered materials, has attracted much interest owing to potential optoelectronics, nanoelectronics, and biomedicine applications. Little is known about its toxicity, such as whether it could be as toxic as white phosphorus. In response to the possibility of BP employment into commercial products and biomedical devices, its cytotoxicity to human lung carcinoma epithelial cells (A549) was investigated. Following a 24 h exposure of the cells with different BP concentrations, cell viability assessments were conducted using water-soluble tetrazolium salt (WST-8) and methylthiazolyldiphenyltetrazolium bromide (MTT) assays. The toxicological effects were found to be dose-dependent, with BP reducing cell viabilities to 48% (WST-8) and 34% (MTT) at 50 µg mL(-1) exposure. This toxicity was observed to be generally intermediate between that of graphene oxides and exfoliated transition-metal dichalcogenides (MoS2, WS2, WSe2). The relatively low toxicity paves the way to utilization of black phosphorus.