Multi-dimensional signals coupling of simultaneous acquisition stripping current with laser-induced breakdown spectroscopy for accurate analysis of Cd(II) in coexisting Cu(II).

BACKGROUND: Despite significant advancements in detecting Cd(II) using nanomaterials-modified sensitive interfaces, most detection methods rely solely on a single electrochemical stripping current to indicate concentration. This approach often overlooks potential inaccuracies caused by interference from coexisting ions. Therefore, establishing multi-dimensional signals that accurately reflect Cd(II) concentration in solution is crucial. RESULTS: In this study, we developed a system integrating concentration, electrochemical stripping current, and laser-induced breakdown spectroscopy (LIBS) characteristic peak intensity through in-situ laser-induced breakdown spectroscopy and electrochemical integrated devices. By simultaneously acquiring multi-dimensional signals to dynamically track the electrochemical deposition and stripping processes, we observed that replacement reactions occur between Cu(II) and Cd(II) on the surface of Ru-doped MoS2 modified carbon paper electrodes (Ru-MoS2/CP). These reactions facilitate the oxidation of Cd(0) to Cd(II) during the stripping process, significantly increasing the currents of Cd(II). Remarkably, the ingenious design of the Ru-MoS2 sensitive interface allowed for the undisturbed deposition of Cu(II) and Cd(II) during the electrochemical deposition process. Consequently, our in-situ integrated device achieved accurate detection of Cd(II) in complex environments, boasting a detection sensitivity of 8606.5 counts µM⁻1. SIGNIFICANCE: By coupling multi-dimensional signals from stripping current and LIBS spectra, we revealed the interference process between Cu(II) and Cd(II), providing valuable insights for accurate electrochemical analysis of heavy metal ions in complex water environments.

Transforming crystal structures of cobalt molybdate to generate electron-rich sites for electrochemical detection of Pb(II).

BACKGROUND: Most of the investigations on distinct crystal structures of catalysts are individually focused on the difference of surface functional groups or adsorption properties, but rarely explore the changes of active sites to affect the electrocatalytic performance. Catalysts with diverse crystal structures had been applied to modified electrodes in different electrocatalytic reactions. However, there is currently a lack of an essential understanding for the role of real active sites in catalysts with crystalline structures in electroanalysis, which is crucial for designing highly sensitive sensing interfaces. RESULTS: Herein, cobalt molybdate with divergent crystal structures (α-CoMoO4 and ß-CoMoO4) were synthesized by adjusting the calcination temperature, indicating that α-CoMoO4 (800 °C) (60.00 µA µM-1) had the highest catalytic ability than ß-CoMoO4 (700 °C) (38.68 µA µM-1) and α-CoMoO4 (900 °C) (29.55 µA µM-1) for the catalysis of Pb(II). It was proved that the proportion of Co(II) and Mo(IV) as electron-rich sites in α-CoMoO4 (800 °C) were higher than ß-CoMoO4 (700 °C) and α-CoMoO4 (900 °C), possessing more electrons to participate in the valence cycles of Co(II)/Co(III) and Mo(IV)/Mo(VI) to boost the catalytic reduction of Pb(II). Specifically, Co(II) transferred a part of electrons to Mo(VI), promoting the formation of Mo(IV). Co(II) and Mo(IV), as the electron-rich sites, providing electrons to Pb(II), further accelerating the conversion of Pb(II) into Pb(0). SIGNIFICANCE: In the process of detecting Pb(II), the CoMoO4 structures under different temperatures have distinct content of electron-rich sites Co(II) and Mo(IV). α-CoMoO4 (800 °C), with the highest content are benefited to detect Pb(II). This work is conducive to understanding the effect of the changes of active sites resulting from crystal transformation on the electrocatalytic performance, and provides a way to construct sensitive electrochemical interfaces of distinct active sites.

Comprehensive analysis of the Spartina alterniflora WD40 gene family reveals the regulatory role of SaTTG1 in plant development.

Introduction: The WD40 gene family, prevalent in eukaryotes, assumes diverse roles in cellular processes. Spartina alterniflora, a halophyte with exceptional salt tolerance, flood tolerance, reproduction, and diffusion ability, offers great potential for industrial applications and crop breeding analysis. The exploration of growth and development-related genes in this species offers immense potential for enhancing crop yield and environmental adaptability, particularly in industrialized plantations. However, the understanding of their role in regulating plant growth and development remains limited. Methods: In this study, we conducted a comprehensive analysis of WD40 genes in S. alterniflora at the whole-genome level, delving into their characteristics such as physicochemical properties, phylogenetic relationships, gene architecture, and expression patterns. Additionally, we cloned the TTG1 gene, a gene in plant growth and development across diverse species. Results: We identified a total of 582 WD40 proteins in the S. alterniflora genome, exhibiting an uneven distribution across chromosomes. Through phylogenetic analysis, we categorized the 582 SaWD40 proteins into 12 distinct clades. Examining the duplication patterns of SaWD40 genes, we observed a predominant role of segmental duplication in their expansion. A substantial proportion of SaWD40 gene duplication pairs underwent purifying selection through evolution. To explore the functional aspects, we selected SaTTG1, a homolog of Arabidopsis TTG1, for overexpression in Arabidopsis. Subcellular localization analysis revealed that the SaTTG1 protein localized in the nucleus and plasma membrane, exhibiting transcriptional activation in yeast cells. The overexpression of SaTTG1 in Arabidopsis resulted in early flowering and increased seed size. Discussion: These outcomes significantly contribute to our understanding of WD40 gene functions in halophyte species. The findings not only serve as a valuable foundation for further investigations into WD40 genes in halophyte but also offer insights into the molecular mechanisms governing plant development, offering potential avenues in molecular breeding.

The effect of collectivism-oriented human resource management on employee resilience of hospitality employees.

Introduction: In the face of an increasingly challenging and rapidly evolving business environment, not all the employees exhibit the requisite resilience necessary to recover from adversity. From both the individual and organizational perspectives, enhancing employee resilience emerges as a critical issue not only in the practical and academic fields. In the Chinese culture, this research aims to investigate how and why collectivism-oriented human resource management (C-HRM) fosters employee resilience. Drawing on the group engagement model, we propose a serial mediating effect of perceived overall fairness and three dimensions of social identity between C-HRM and employee resilience. Methods: Using a sample of frontline employees in the hospitality industry, we conducted a field survey among 342 employees (study 1) and a two-wave online survey among 294 hospitality employees (study 2). Results: Findings from empirical analysis indicated that C-HRM significantly increases overall fairness perception of hospitality frontline employees and in turn, their identification and respect, which further fertilize employee resilience. In addition, the indirect effect of C-HRM on employee resilience through perceived overall fairness and pride was not statistically significant. Discussion: These important findings are expected to help employees cope with the workplace pressures caused by ongoing challenges and change, and contribute to sustainable career development.

In-situ precipitation zero-valent Co on Co2VO4 to activate oxygen vacancies and enhance bimetallic ions redox for efficient detection toward Hg(II).

Despite the widespread utilization of variable valence metals in electrochemistry, it is still a formidable challenge to enhance the valence conversion efficiency to achieve excellent catalytic activity without introducing heterophase elements. Herein, the in-situ precipitation of Co particles on Co2VO4 not only enhanced the concentration of oxygen vacancies (Ov) but also generated a greater number of low-valence metals, thereby enabling efficient reduction towards Hg(II). The electroanalysis results demonstrate that the sensitivity of Co/Co2VO4 towards Hg(II) was measured at an impressive value of 1987.74 µA µM-1 cm-2, significantly surpassing previously reported results. Further research reveals that Ov acted as the main adsorption site to capture Hg(II). The redox reactions of Co2+/Co3+ and V3+/V4+ played a synergistic role in the reduction of Hg(II), accompanied by the continuous supply of electrons from zero-valent Co to expedite the valence cycle. The Co/Co2VO4/GCE presented remarkable selectivity towards Hg(II), with excellent stability, reproducibility, and anti-interference capability. The electrode also exhibited minimal sensitivity fluctuations towards Hg(II) in real water samples, underscoring its practicality for environmental applications. This study elucidates the mechanism underlying the surface redox reaction of metal oxides facilitated by zero-valent metals, providing us with new strategies for further design of efficient and practical sensors.

Fully Integrated Multiplexed Wristwatch for Real-Time Monitoring of Electrolyte Ions in Sweat.

Considerable progress has already been made in sweat sensors based on electrochemical methods to realize real-time monitoring of biomarkers. However, realizing long-term monitoring of multiple targets at the atomic level remains extremely challenging, in terms of designing stable solid contact (SC) interfaces and fully integrating multiple modules for large-scale applications of sweat sensors. Herein, a fully integrated wristwatch was designed using mass-manufactured sensor arrays based on hierarchical multilayer-pore cross-linked N-doped porous carbon coated by reduced graphene oxide (NPCs@rGO-950) microspheres with high hydrophobicity as core SC, and highly selective monitoring simultaneously for K+, Na+, and Ca2+ ions in human sweat was achieved, exhibiting near-Nernst responses almost without forming an interfacial water layer. Combined with computed tomography, solid-solid interface potential diffusion simulation results reveal extremely low interface diffusion potential and high interface capacitance (598 µF), ensuring the excellent potential stability, reversibility, repeatability, and selectivity of sensor arrays. The developed highly integrated-multiplexed wristwatch with multiple modules, including SC, sensor array, microfluidic chip, signal transduction, signal processing, and data visualization, achieved reliable real-time monitoring for K+, Na+, and Ca2+ ion concentrations in sweat. Ingenious material design, scalable sensor fabrication, and electrical integration of multimodule wearables lay the foundation for developing reliable sweat-sensing systems for health monitoring.

The Spartina alterniflora genome sequence provides insights into the salt-tolerance mechanisms of exo-recretohalophytes.

Spartina alterniflora is an exo-recretohalophyte Poaceae species that is able to grow well in seashore, but the genomic basis underlying its adaptation to salt tolerance remains unknown. Here, we report a high-quality, chromosome-level genome assembly of S. alterniflora constructed through PacBio HiFi sequencing, combined with high-throughput chromosome conformation capture (Hi-C) technology and Illumina-based transcriptomic analyses. The final 1.58 Gb genome assembly has a contig N50 size of 46.74 Mb. Phylogenetic analysis suggests that S. alterniflora diverged from Zoysia japonica approximately 21.72 million years ago (MYA). Moreover, whole-genome duplication (WGD) events in S. alterniflora appear to have expanded gene families and transcription factors relevant to salt tolerance and adaptation to saline environments. Comparative genomics analyses identified numerous species-specific genes, significantly expanded genes and positively selected genes that are enriched for 'ion transport' and 'response to salt stress'. RNA-seq analysis identified several ion transporter genes including the high-affinity K+ transporters (HKTs), SaHKT1;2, SaHKT1;3 and SaHKT1;8, and high copy number of Salt Overly Sensitive (SOS) up-regulated under high salt conditions, and the overexpression of SaHKT2;4 in Arabidopsis thaliana conferred salt tolerance to the plant, suggesting specialized roles for S. alterniflora to adapt to saline environments. Integrated metabolomics and transcriptomics analyses revealed that salt stress activate glutathione metabolism, with differential expressions of several genes such as γ-ECS, GSH-S, GPX, GST and PCS in the glutathione metabolism. This study suggests several adaptive mechanisms that could contribute our understanding of evolutional basis of the halophyte.

Highly Accurate Determination of the Total Amount of Pb2+ and Pb(OH)+ in a Natural Water Environment Revealed by Dynamic Simulation and DFT Calculation: Benefit from the Electron Inverse Effect of Pt Nanoclusters over Defective g-C3N4.

Although utilizing nanomaterial-modified electrodes for lead ion detection has achieved great success, most of them are carried out under acidic conditions and ignore the variation of Pb(II) speciation at different pH conditions, leading to the potential inaccuracy of Pb(II) detection in a neutral natural water environment. Thus, designing a novel catalyst with high accuracy for the detection of various forms of the total amount of Pb(II) (Pb2+ and Pb(OH)+) in neutral waters is significant. Herein, Pt nanoclusters (Pt NCs) were elaborately constructed and stabilized on the Co single-atom-doped g-C3N4 with abundant N vacancies (Pt NCs/VN-C3N4), which achieved the ultrasensitive detection (102.16 µM µA-1) of Pb(II) in neutral conditions. The dynamic simulation and theoretical calculations reveal that the parallel deposition of Pb2+ and Pb(OH)+ occurs on the electrode surface modified by Pt NCs/VN-C3N4, and the current peaks of Pb(II) are cocontributed by Pb2+ and Pb(OH)+ species. An "electron inverse" phenomenon in Pt NCs/VN-C3N4 from the VN-C3N4 substrate to Pt NCs endows Pt NCs in an electron-rich state, serving as active centers to promote rapid and efficient reduction for both Pb2+ and Pb(OH)+, facilitating the accurate detection of the total amount of Pb(II) in all forms in the actual water environment.

Development and Validation of a Risk Score for Mild Cognitive Impairment in Individuals with Type 2 Diabetes in China: A Practical Cognitive Prescreening Tool.

Aim: Numerous evidence suggests that diabetes increases the risk of cognitive impairment. This study aimed to develop and validate a multivariable risk score model to identify mild cognitive impairment (MCI) in patients with type 2 diabetes mellitus (T2DM). Methods: This cross-sectional study included 1256 inpatients (age: 57.5 ± 11.2 years) with T2DM in a tertiary care hospital in China. MCI was diagnosed according to the criteria recommended by the National Institute on Aging-Alzheimer's Association Workgroup, and a MoCA score of 19-25 indicated MCI. Participants were randomly allocated into the derivation and validation sets at 7:3 ratio. Logistic regression models were used to identify predictors for MCI in the derivation set. A scoring system based on the predictors' beta coefficient was developed. Predictive ability of the risk score was tested by discrimination and calibration methods. Results: Totally 880 (285 with MCI, 32.4%) and 376 (167 with MCI, 33.8%) patients were allocated in the derivation and validation set, respectively. Age, education, HbA1c, self-reported history of severe hypoglycemia, and microvascular disease were identified as predictors for MCI and constituted the risk score. The AUCs (95% CI) of the risk score were 0.751 (0.717, 0.784) in derivation set and 0.776 (0.727, 0.824) in validation set. The risk score showed good apparent calibration of observed and predicted MCI probabilities and was capable of stratifying individuals into 3 risk categories by two cut-off points (low risk: ≤ 3, medium risk: 4-13, and high risk ≥ 14). Conclusion: The risk score based on age, education, HbA1c, self-reported history of severe hypoglycemia, and microvascular disease can effectively assess MCI risk in adults with T2DM at different age. It can serve as a practical prescreening tool for early detection of MCI in daily diabetes care.

Spatial Mass Cytometry-Based Single-Cell Imaging Reveals a Disrupted Epithelial-Immune Axis in Prurigo Nodularis.

Prurigo nodularis (PN) is a chronic, inflammatory skin condition that disproportionately affects African Americans and features intensely pruritic, hyperkeratotic nodules on the extremities and trunk. PN is understudied compared with other inflammatory skin diseases, with the spatial organization of the cutaneous infiltrate in PN yet to be characterized. In this work, we employ spatial imaging mass cytometry to visualize PN lesional skin inflammation and architecture with single-cell resolution through an unbiased machine learning approach. PN lesional skin has increased expression of caspase 3, NF-kB, and phosphorylated signal transducer and activator of transcription 3 compared with healthy skin. Keratinocytes in lesional skin are subdivided into CD14+CD33+, CD11c+, CD63+, and caspase 3-positive innate subpopulations. CD14+ macrophage populations expressing phosphorylated extracellular signal-regulated kinase 1/2 correlate positively with patient-reported itch (P = .006). Hierarchical clustering reveals a cluster of patients with PN with greater atopy, increased NF-kB+ signal transducer and activator of transcription 3-positive phosphorylated extracellular signal-regulated kinase 1/2-positive monocyte-derived myeloid dendritic cells, and increased vimentin expression (P < .05). Neighborhood analysis finds interactions between CD14+ macrophages, CD3+ T cells, monocyte-derived myeloid dendritic cells, and keratinocytes expressing innate immune markers. These findings highlight phosphorylated extracellular signal-regulated kinase-positive CD14+ macrophages as contributors to itch and suggest an epithelial-immune axis in PN pathogenesis.

Mapping and identification of a reverse mutation of Rht2 that enhances plant height and thousand grain weight in an elite wheat mutant induced by spaceflight.

As climate change continues to negatively impact our farmlands, abiotic factors like salinity and drought stress increasingly threaten global food security. The development of elite germplasms with resistance to multiple abiotic stresses is essential for breeding climate-resilient wheat cultivars. In this study, we determined that the previously reported salt-tolerant st1 mutant, obtained via spaceflight mutagenesis, may also resist to drought stress at the seedling stage. Moreover, our field trial revealed that yield-related traits including plant height, 1000-grain weight, and spike number per plant were significantly increased in st1 compared to the wild type. An F2 population of 334 individuals derived from a cross between the wild type and st1 displayed a bimodal distribution indicating that st1 plant height is controlled by a single major gene. Our Bulked Segregant Analysis and exome capture sequencing indicate that this gene is located on chromosome 4D. Further genetic linkage and gene sequence analysis suggests that a reverse mutation of Rht2 is putatively responsible for plant height variation in st1. Our genotypic and phenotypic analysis of the F2 population and F3 lines indicate that this reverse mutation significantly increases plant height and thousand grain weight but slightly decreases spike number per plant. Together, these results supply helpful information for the utilization of Rht2 in wheat breeding and provide an important material for breeding environmentally resilient, high-yield wheat varieties.

Phosphorus-doped synergy of phase change in heterogeneous catalysts of NiS-NiS2 for efficient electrocatalysis of Pb(II).

A fundamental understanding of the electroanalytical activity of transition metal sulfide electrocatalysts, especially the origin of the electrocatalytic reactivity on the surface sites of heterostructures with multiple crystalline phases, is essential for the design of low-cost and highly efficient nonprecious metal electrocatalysts for further scientific and technological achievements. Herein, we injected P into NiS and occupied the S sites through a doping strategy. The redistributed electronic structure induced the construction of heterostructures, which significantly improved the structure and chemical state of electrochemically inert NiS. The phase-change mechanism between NiS and NiS2 synergistically catalyzes Pb(II), while the P and S sites jointly lose electrons. Moreover, the constructed heterojunction sensor shows the a sensitivity of 83.43 µA µM-1 to Pb(II) with a theoretical limit of detection of 48 nM, as well as excellent stability, reproducibility, and anti-interference ability. The accurate detection in real water further reveals the potential of this sensor for practical applications. This study provides a guiding strategy for improving electrochemically inert materials to design highly active electrocatalytic interfaces, which has important implications for the development of highly efficient electrode-sensitive materials similar to precious metals to achieve accurate electrical analysis.

Asthma heterogeneity among Asian American children: The California Health Interview Survey.

BACKGROUND: The Asian American (AsA) population is heterogenous and rapidly growing; however, little is known regarding childhood asthma burden among AsA ethnic groups. The relation between obesity and asthma in AsA ethnic groups also remains unclear. OBJECTIVE: To evaluate asthma prevalence and the relation of obesity to asthma risk among children in 7 AsA ethnic groups. METHODS: We analyzed data from the California Health Interview Survey from 2011 to 2020. AsA ethnicities were self-reported. Body mass index z-scores, calculated from self-reported height/weight, were used to categorize children by obesity status, based on body mass index-for-age growth charts. Prevalence of self-reported lifetime doctor-diagnosed asthma and asthma attack in the last 12 months was calculated. We performed multivariable logistic regressions adjusting for age and sex. RESULTS: Of 34,146 survey respondents, 12.2% non-Hispanic White and 12.5% AsA children reported lifetime asthma. Among AsA ethnic groups, however, lifetime asthma ranged from 5.1% (Korean American) to 21.5% (Filipino American). Non-Hispanic White children and AsA children had a similar lifetime asthma prevalence (adjusted odds ratio [aOR], 1.05; 95% CI, 0.71-1.55; P = .81), but prevalence was lower in Korean American children (aOR, 0.37; 95% CI, 0.19-0.73; P = .004) and higher in Filipino American children (aOR, 1.97; 95% CI, 1.22-3.17; P = .006). The lifetime asthma prevalence of different AsA ethnic groups persisted even when stratified by obesity status. CONCLUSION: Childhood lifetime asthma prevalence varied among AsA ethnic groups, with lowest prevalence in Korean American children and highest prevalence in Filipino American. Further characterization of asthma burden among AsA ethnic groups may help guide asthma screening and prevention measures and offer new insights into asthma pathogenesis.

In Situ Laser-Induced Breakdown Spectroscopy for Chromium Speciation Analysis Based on the Interactions of Oxygen-Containing Groups with Functionalized Co3O4-rGO: Evidence from Advanced Optical Techniques and Density Functional Theoretical Calculations under Electric Field.

Achieving accurate detection of different speciations of heavy metal ions (HMIs) in an aqueous solution is an urgent problem due to the different bioavailabilities and physiological toxicity. Herein, we nominated a novel strategy to detect HCrO4- and Cr(OH)2+ at a trace level via the electrochemical sensitive surface constructed by Co3O4-rGO modified with amino and carboxyl groups, which revealed that the interactions between distinct functional groups and different oxygen-containing groups of target ions are conducive to the susceptible and anti-interference detection. The detection sensitivities of 19.46 counts µg-1 L for HCrO4- and 13.44 counts µg-1 L for Cr(OH)2+ were obtained under optimal conditions, while the limits of detection were 0.10 and 0.12 µg L-1, respectively. Satisfactory anti-interference and actual water sample analysis results were obtained. A series of advanced optical techniques like X-ray photoelectron spectroscopy, X-ray absorption near-edge structure technology, and density functional theory calculations under an electric field demonstrated that chemical interactions between groups contribute more to the fixation of target ions than electrical attraction alone. The presence of oxygen-containing groups distinct from simple ionic forms was a critical factor in the selectivity and anti-interference detection. Furthermore, the valence cycle of Co(II)/(III) synergistically boosted the detection performance. This research provides a promising tactic from the microscopic perspective of groups' interactions to accomplish the precise speciation analysis of HMIs in the water environment.

Mining salt stress-related genes in Spartina alterniflora via analyzing co-evolution signal across 365 plant species using phylogenetic profiling.

With the increasing number of sequenced species, phylogenetic profiling (PP) has become a powerful method to predict functional genes based on co-evolutionary information. However, its potential in plant genomics has not yet been fully explored. In this context, we combined the power of machine learning and PP to identify salt stress-related genes in a halophytic grass, Spartina alterniflora, using evolutionary information generated from 365 plant species. Our results showed that the genes highly co-evolved with known salt stress-related genes are enriched in biological processes of ion transport, detoxification and metabolic pathways. For ion transport, five identified genes coding two sodium and three potassium transporters were validated to be able to uptake Na+. In addition, we identified two orthologs of trichome-related AtR3-MYB genes, SaCPC1 and SaCPC2, which may be involved in salinity responses. Genes co-evolved with SaCPCs were enriched in functions related to the circadian rhythm and abiotic stress responses. Overall, this work demonstrates the feasibility of mining salt stress-related genes using evolutionary information, highlighting the potential of PP as a valuable tool for plant functional genomics. Supplementary Information: The online version contains supplementary material available at 10.1007/s42994-023-00125-5.

Comparative Analysis of Six Chloroplast Genomes in Chenopodium and Its Related Genera (Amaranthaceae): New Insights into Phylogenetic Relationships and the Development of Species-Specific Molecular Markers.

Species within the genus Chenopodium hold significant research interest due to their nutritional richness and salt tolerance. However, the morphological similarities among closely related species and a dearth of genomic resources have impeded their comprehensive study and utilization. In the present research, we conduct the sequencing and assembly of chloroplast (cp) genomes from six Chenopodium and related species, five of which were sequenced for the first time. These genomes ranged in length from 151,850 to 152,215 base pairs, showcased typical quadripartite structures, and encoded 85 protein-coding genes (PCGs), 1 pseudogene, 37 tRNA genes, and 8 rRNA genes. Compared with the previously published sequences of related species, these cp genomes are relatively conservative, but there are also some interspecific differences, such as inversion and IR region contraction. We discerned 929 simple sequence repeats (SSRs) and a series of highly variable regions across 16 related species, predominantly situated in the intergenic spacer (IGS) region and introns. The phylogenetic evaluations revealed that Chenopodium is more closely related to genera such as Atriplex, Beta, Dysphania, and Oxybase than to other members of the Amaranthaceae family. These lineages shared a common ancestor approximately 60.80 million years ago, after which they diverged into distinct genera. Based on InDels and SNPs between species, we designed 12 pairs of primers for species identification, and experiments confirmed that they could completely distinguish 10 related species.

Modulating paired Ir-O-Ir via electronic perturbations of correlated Ir single atoms to overcome catalytic selectivity.

Single-atom catalysts have been extensively utilized for electrocatalysis, in which electronic metal-support interactions are typically employed to stabilize single atoms. However, this neglects the metal-metal interactions of adjacent atoms, which are essential for the fine-tuning of selective sites. Herein, the high-loading of Ir single atoms (Ir SAs) (8.9 wt%) were adjacently accommodated into oxygen vacancy-rich Co3O4 nanosheets (Ir SAs/Co3O4). Electronic perturbations for both Ir single atoms and Co3O4 supports were observed under electronic metal-support and metal-metal interactions, thus generating Ir-O-Co/Ir units. Electrons were transferred from Co and Ir to O atoms, inducing the depletion of 3d/5d states in Co/Ir and the occupation of 2p states in O atoms to stabilize the Ir SAs. Moreover, the O atoms of Ir-O-Ir functioned as the main active sites for the electrocatalysis of As(iii), which reduced the energy barrier for the rate-determining step. This was due to the stronger electronic affinities for intermediates from reduction of As(iii), which were completely distinct from other coordinated O atoms of Co3O4 or IrO2. Consequently, the resultant Ir SAs/Co3O4 exhibited far more robust electrocatalytic activities than IrO2/Co3O4 and Co3O4 in the electrocatalysis of As(iii). Moreover, there was a strong orbital coupling effect between the coordinated O atoms of Ir SAs and the -OH of H3AsO3, thus exhibiting superior selectivity for As(iii) in contrast to other common heavy metal cations. This work offers useful insights into the rational design of intriguing SACs with high selectivity and stability for the electrocatalysis and electrochemical analysis of pollutants on an electronic level.

Revealing the solid-solution interface interference behaviors between Cu2+ and As(III) via partial peak area analysis of simulations and experiments.

The mutual interference in the sensing detection of heavy metal ions (HMIs) is considerably serious and complex. Besides, the co-existed ions may change the stripping peak intensity, shape and position of the target ion, which partly makes peak current analysis inaccurate. Herein, a promising approach of partial peak area analysis was proposed firstly to research the mutual interference. The interference between two species on their electrodeposition processes was investigated by simulating different kinetics parameters, including surface coverage, electro-adsorption, -desorption rate constant, etc. It was proved that the partial peak area is sensitive and regular to these interference kinetics parameters, which is favorable for distinctly identifying different interferences. Moreover, the applicability of the partial peak area analysis was verified on the experiments of Cu2+, As(III) interference at four sensing interfaces: glassy carbon electrode, gold electrode, Co3O4, and Fe2O3 nanoparticles modified electrodes. The interference behaviors between Cu2+ and As(III) relying on solid-solution interfaces were revealed and confirmed by physicochemical characterizations and kinetics simulations. This work proposes a new descriptor (partial peak area) to recognize the interference mechanism and provides a meaningful guidance for accurate detection of HMIs in actual water environment.

Bimodal interferences of Pb(II) induced by parallel deposition in Pb(II)-Cu(II) electrochemical detections: Voltammetric signals analysis combined with numerical simulations on transient interfacial phenomena.

The perplexity of double peaks in Pb(II) detections has been a threat to the reliability of Pb(II) electroanalysis results for a long term. For the complexity of electrode interfaces, rare studies were taken on mechanisms of Pb(II) double peaks through interfacial kinetics. In this work, analyses on experimental signals and interfacial simulations were working together to reveal that the generation of Pb(II) double peaks in Pb(II)-Cu(II) systems is the deposition of Pb(II) on Cu deposits occurring in parallel. By applying anode stripping voltammetry and cyclic voltammetry, a parallel deposition reaction was found to influence the shape of Pb(II) peaks, and the existence of the second peak was controlled through the adjustment of experimental conditions. A kinetic model was built to reveal the interference of electroanalysis signals caused by a parallel deposition reaction and simulations based on the model were combined with experiments to illustrate that double peaks of Pb(II) were caused by the parallel deposition on Cu(II) deposits. This work proposes another insight of Pb(II) double peaks from macroscale kinetics and pays more attention on the dynamic procedure of electroanalysis interfaces, which makes the study on environmental electroanalysis interface phenomena more clear and is enlightening to develop efficient electrical methods for pollutant monitoring.

Deep learning-enabled discovery and characterization of HKT genes in Spartina alterniflora.

Spartina alterniflora is a halophyte that can survive in high-salinity environments, and it is phylogenetically close to important cereal crops, such as maize and rice. It is of scientific interest to understand why S. alterniflora can live under such extremely stressful conditions. The molecular mechanism underlying its high-saline tolerance is still largely unknown. Here we investigated the possibility that high-affinity K+ transporters (HKTs), which function in salt tolerance and maintenance of ion homeostasis in plants, are responsible for salt tolerance in S. alterniflora. To overcome the imprecision and unstable of the gene screening method caused by the conventional sequence alignment, we used a deep learning method, DeepGOPlus, to automatically extract sequence and protein characteristics from our newly assemble S. alterniflora genome to identify SaHKTs. Results showed that a total of 16 HKT genes were identified. The number of S. alterniflora HKTs (SaHKTs) is larger than that in all other investigated plant species except wheat. Phylogenetically related SaHKT members had similar gene structures, conserved protein domains and cis-elements. Expression profiling showed that most SaHKT genes are expressed in specific tissues and are differentially expressed under salt stress. Yeast complementation expression analysis showed that type I members SaHKT1;2, SaHKT1;3 and SaHKT1;8 and type II members SaHKT2;1, SaHKT2;3 and SaHKT2;4 had low-affinity K+ uptake ability and that type II members showed stronger K+ affinity than rice and Arabidopsis HKTs, as well as most SaHKTs showed preference for Na+ transport. We believe the deep learning-based methods are powerful approaches to uncovering new functional genes, and the SaHKT genes identified are important resources for breeding new varieties of salt-tolerant crops.